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v3.1
 
   1/*
   2   rbd.c -- Export ceph rados objects as a Linux block device
   3
   4
   5   based on drivers/block/osdblk.c:
   6
   7   Copyright 2009 Red Hat, Inc.
   8
   9   This program is free software; you can redistribute it and/or modify
  10   it under the terms of the GNU General Public License as published by
  11   the Free Software Foundation.
  12
  13   This program is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with this program; see the file COPYING.  If not, write to
  20   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22
  23
  24   For usage instructions, please refer to:
  25
  26                 Documentation/ABI/testing/sysfs-bus-rbd
  27
  28 */
  29
  30#include <linux/ceph/libceph.h>
  31#include <linux/ceph/osd_client.h>
  32#include <linux/ceph/mon_client.h>
 
 
  33#include <linux/ceph/decode.h>
  34#include <linux/parser.h>
 
  35
  36#include <linux/kernel.h>
  37#include <linux/device.h>
  38#include <linux/module.h>
 
  39#include <linux/fs.h>
  40#include <linux/blkdev.h>
 
 
 
  41
  42#include "rbd_types.h"
  43
  44#define DRV_NAME "rbd"
  45#define DRV_NAME_LONG "rbd (rados block device)"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  46
  47#define RBD_MINORS_PER_MAJOR	256		/* max minors per blkdev */
 
 
  48
  49#define RBD_MAX_MD_NAME_LEN	(96 + sizeof(RBD_SUFFIX))
  50#define RBD_MAX_POOL_NAME_LEN	64
  51#define RBD_MAX_SNAP_NAME_LEN	32
  52#define RBD_MAX_OPT_LEN		1024
  53
  54#define RBD_SNAP_HEAD_NAME	"-"
  55
  56#define DEV_NAME_LEN		32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  57
  58#define RBD_NOTIFY_TIMEOUT_DEFAULT 10
 
 
 
 
  59
  60/*
  61 * block device image metadata (in-memory version)
  62 */
  63struct rbd_image_header {
  64	u64 image_size;
  65	char block_name[32];
  66	__u8 obj_order;
  67	__u8 crypt_type;
  68	__u8 comp_type;
  69	struct rw_semaphore snap_rwsem;
 
 
 
 
  70	struct ceph_snap_context *snapc;
  71	size_t snap_names_len;
  72	u64 snap_seq;
  73	u32 total_snaps;
  74
  75	char *snap_names;
  76	u64 *snap_sizes;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  77
  78	u64 obj_version;
  79};
  80
  81struct rbd_options {
  82	int	notify_timeout;
 
 
  83};
  84
  85/*
  86 * an instance of the client.  multiple devices may share a client.
  87 */
  88struct rbd_client {
  89	struct ceph_client	*client;
  90	struct rbd_options	*rbd_opts;
  91	struct kref		kref;
  92	struct list_head	node;
  93};
  94
  95struct rbd_req_coll;
 
 
 
  96
  97/*
  98 * a single io request
  99 */
 100struct rbd_request {
 101	struct request		*rq;		/* blk layer request */
 102	struct bio		*bio;		/* cloned bio */
 103	struct page		**pages;	/* list of used pages */
 104	u64			len;
 105	int			coll_index;
 106	struct rbd_req_coll	*coll;
 107};
 108
 109struct rbd_req_status {
 110	int done;
 111	int rc;
 112	u64 bytes;
 
 
 
 
 
 
 
 
 
 
 
 
 
 113};
 114
 115/*
 116 * a collection of requests
 117 */
 118struct rbd_req_coll {
 119	int			total;
 120	int			num_done;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 121	struct kref		kref;
 122	struct rbd_req_status	status[0];
 123};
 124
 125struct rbd_snap {
 126	struct	device		dev;
 127	const char		*name;
 128	size_t			size;
 129	struct list_head	node;
 130	u64			id;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 131};
 132
 133/*
 134 * a single device
 135 */
 136struct rbd_device {
 137	int			id;		/* blkdev unique id */
 138
 139	int			major;		/* blkdev assigned major */
 
 140	struct gendisk		*disk;		/* blkdev's gendisk and rq */
 141	struct request_queue	*q;
 142
 143	struct ceph_client	*client;
 144	struct rbd_client	*rbd_client;
 145
 146	char			name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
 147
 148	spinlock_t		lock;		/* queue lock */
 149
 150	struct rbd_image_header	header;
 151	char			obj[RBD_MAX_OBJ_NAME_LEN]; /* rbd image name */
 152	int			obj_len;
 153	char			obj_md_name[RBD_MAX_MD_NAME_LEN]; /* hdr nm. */
 154	char			pool_name[RBD_MAX_POOL_NAME_LEN];
 155	int			poolid;
 156
 157	struct ceph_osd_event   *watch_event;
 158	struct ceph_osd_request *watch_request;
 159
 160	char                    snap_name[RBD_MAX_SNAP_NAME_LEN];
 161	u32 cur_snap;	/* index+1 of current snapshot within snap context
 162			   0 - for the head */
 163	int read_only;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 164
 165	struct list_head	node;
 
 166
 167	/* list of snapshots */
 168	struct list_head	snaps;
 
 
 
 
 169
 170	/* sysfs related */
 171	struct device		dev;
 
 172};
 173
 174static struct bus_type rbd_bus_type = {
 175	.name		= "rbd",
 
 
 
 
 
 
 
 176};
 177
 178static spinlock_t node_lock;      /* protects client get/put */
 179
 180static DEFINE_MUTEX(ctl_mutex);	  /* Serialize open/close/setup/teardown */
 181static LIST_HEAD(rbd_dev_list);    /* devices */
 182static LIST_HEAD(rbd_client_list);      /* clients */
 183
 184static int __rbd_init_snaps_header(struct rbd_device *rbd_dev);
 185static void rbd_dev_release(struct device *dev);
 186static ssize_t rbd_snap_rollback(struct device *dev,
 187				 struct device_attribute *attr,
 188				 const char *buf,
 189				 size_t size);
 190static ssize_t rbd_snap_add(struct device *dev,
 191			    struct device_attribute *attr,
 192			    const char *buf,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 193			    size_t count);
 194static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev,
 195				  struct rbd_snap *snap);;
 
 
 
 196
 
 
 
 
 197
 198static struct rbd_device *dev_to_rbd(struct device *dev)
 199{
 200	return container_of(dev, struct rbd_device, dev);
 201}
 202
 203static struct device *rbd_get_dev(struct rbd_device *rbd_dev)
 204{
 205	return get_device(&rbd_dev->dev);
 206}
 207
 208static void rbd_put_dev(struct rbd_device *rbd_dev)
 209{
 210	put_device(&rbd_dev->dev);
 211}
 212
 213static int __rbd_update_snaps(struct rbd_device *rbd_dev);
 
 
 214
 215static int rbd_open(struct block_device *bdev, fmode_t mode)
 
 
 
 
 216{
 217	struct gendisk *disk = bdev->bd_disk;
 218	struct rbd_device *rbd_dev = disk->private_data;
 219
 220	rbd_get_dev(rbd_dev);
 
 
 
 
 221
 222	set_device_ro(bdev, rbd_dev->read_only);
 
 
 
 223
 224	if ((mode & FMODE_WRITE) && rbd_dev->read_only)
 225		return -EROFS;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 226
 227	return 0;
 228}
 229
 230static int rbd_release(struct gendisk *disk, fmode_t mode)
 231{
 232	struct rbd_device *rbd_dev = disk->private_data;
 
 233
 234	rbd_put_dev(rbd_dev);
 
 
 
 235
 236	return 0;
 237}
 238
 239static const struct block_device_operations rbd_bd_ops = {
 240	.owner			= THIS_MODULE,
 241	.open			= rbd_open,
 242	.release		= rbd_release,
 243};
 244
 245/*
 246 * Initialize an rbd client instance.
 247 * We own *opt.
 248 */
 249static struct rbd_client *rbd_client_create(struct ceph_options *opt,
 250					    struct rbd_options *rbd_opts)
 251{
 252	struct rbd_client *rbdc;
 253	int ret = -ENOMEM;
 254
 255	dout("rbd_client_create\n");
 256	rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
 257	if (!rbdc)
 258		goto out_opt;
 259
 260	kref_init(&rbdc->kref);
 261	INIT_LIST_HEAD(&rbdc->node);
 262
 263	rbdc->client = ceph_create_client(opt, rbdc);
 264	if (IS_ERR(rbdc->client))
 265		goto out_rbdc;
 266	opt = NULL; /* Now rbdc->client is responsible for opt */
 267
 268	ret = ceph_open_session(rbdc->client);
 269	if (ret < 0)
 270		goto out_err;
 271
 272	rbdc->rbd_opts = rbd_opts;
 273
 274	spin_lock(&node_lock);
 275	list_add_tail(&rbdc->node, &rbd_client_list);
 276	spin_unlock(&node_lock);
 277
 278	dout("rbd_client_create created %p\n", rbdc);
 279	return rbdc;
 280
 281out_err:
 
 282	ceph_destroy_client(rbdc->client);
 283out_rbdc:
 284	kfree(rbdc);
 285out_opt:
 286	if (opt)
 287		ceph_destroy_options(opt);
 
 
 288	return ERR_PTR(ret);
 289}
 290
 
 
 
 
 
 
 
 291/*
 292 * Find a ceph client with specific addr and configuration.
 
 293 */
 294static struct rbd_client *__rbd_client_find(struct ceph_options *opt)
 295{
 296	struct rbd_client *client_node;
 
 297
 298	if (opt->flags & CEPH_OPT_NOSHARE)
 299		return NULL;
 300
 301	list_for_each_entry(client_node, &rbd_client_list, node)
 302		if (ceph_compare_options(opt, client_node->client) == 0)
 303			return client_node;
 304	return NULL;
 
 
 
 
 
 
 
 
 305}
 306
 307/*
 308 * mount options
 309 */
 310enum {
 311	Opt_notify_timeout,
 312	Opt_last_int,
 
 313	/* int args above */
 314	Opt_last_string,
 
 315	/* string args above */
 
 
 
 
 
 316};
 317
 318static match_table_t rbdopt_tokens = {
 319	{Opt_notify_timeout, "notify_timeout=%d"},
 320	/* int args above */
 321	/* string args above */
 322	{-1, NULL}
 323};
 324
 325static int parse_rbd_opts_token(char *c, void *private)
 326{
 327	struct rbd_options *rbdopt = private;
 328	substring_t argstr[MAX_OPT_ARGS];
 329	int token, intval, ret;
 
 330
 331	token = match_token((char *)c, rbdopt_tokens, argstr);
 332	if (token < 0)
 333		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 334
 335	if (token < Opt_last_int) {
 336		ret = match_int(&argstr[0], &intval);
 337		if (ret < 0) {
 338			pr_err("bad mount option arg (not int) "
 339			       "at '%s'\n", c);
 340			return ret;
 341		}
 342		dout("got int token %d val %d\n", token, intval);
 343	} else if (token > Opt_last_int && token < Opt_last_string) {
 344		dout("got string token %d val %s\n", token,
 345		     argstr[0].from);
 346	} else {
 347		dout("got token %d\n", token);
 348	}
 349
 350	switch (token) {
 351	case Opt_notify_timeout:
 352		rbdopt->notify_timeout = intval;
 353		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 354	default:
 355		BUG_ON(token);
 356	}
 357	return 0;
 358}
 359
 360/*
 361 * Get a ceph client with specific addr and configuration, if one does
 362 * not exist create it.
 
 363 */
 364static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr,
 365			  char *options)
 366{
 367	struct rbd_client *rbdc;
 368	struct ceph_options *opt;
 369	int ret;
 370	struct rbd_options *rbd_opts;
 371
 372	rbd_opts = kzalloc(sizeof(*rbd_opts), GFP_KERNEL);
 373	if (!rbd_opts)
 374		return -ENOMEM;
 
 375
 376	rbd_opts->notify_timeout = RBD_NOTIFY_TIMEOUT_DEFAULT;
 
 
 377
 378	ret = ceph_parse_options(&opt, options, mon_addr,
 379				 mon_addr + strlen(mon_addr), parse_rbd_opts_token, rbd_opts);
 380	if (ret < 0)
 381		goto done_err;
 
 
 
 
 
 382
 383	spin_lock(&node_lock);
 384	rbdc = __rbd_client_find(opt);
 
 
 
 
 
 
 
 
 
 
 385	if (rbdc) {
 386		ceph_destroy_options(opt);
 387
 388		/* using an existing client */
 389		kref_get(&rbdc->kref);
 390		rbd_dev->rbd_client = rbdc;
 391		rbd_dev->client = rbdc->client;
 392		spin_unlock(&node_lock);
 393		return 0;
 
 
 
 
 
 
 
 394	}
 395	spin_unlock(&node_lock);
 396
 397	rbdc = rbd_client_create(opt, rbd_opts);
 398	if (IS_ERR(rbdc)) {
 399		ret = PTR_ERR(rbdc);
 400		goto done_err;
 401	}
 402
 403	rbd_dev->rbd_client = rbdc;
 404	rbd_dev->client = rbdc->client;
 405	return 0;
 406done_err:
 407	kfree(rbd_opts);
 408	return ret;
 409}
 410
 411/*
 412 * Destroy ceph client
 413 */
 414static void rbd_client_release(struct kref *kref)
 415{
 416	struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
 
 417
 418	dout("rbd_release_client %p\n", rbdc);
 419	spin_lock(&node_lock);
 420	list_del(&rbdc->node);
 421	spin_unlock(&node_lock);
 422
 423	ceph_destroy_client(rbdc->client);
 424	kfree(rbdc->rbd_opts);
 425	kfree(rbdc);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 426}
 427
 428/*
 429 * Drop reference to ceph client node. If it's not referenced anymore, release
 430 * it.
 431 */
 432static void rbd_put_client(struct rbd_device *rbd_dev)
 433{
 434	kref_put(&rbd_dev->rbd_client->kref, rbd_client_release);
 435	rbd_dev->rbd_client = NULL;
 436	rbd_dev->client = NULL;
 437}
 438
 439/*
 440 * Destroy requests collection
 441 */
 442static void rbd_coll_release(struct kref *kref)
 443{
 444	struct rbd_req_coll *coll =
 445		container_of(kref, struct rbd_req_coll, kref);
 
 
 
 446
 447	dout("rbd_coll_release %p\n", coll);
 448	kfree(coll);
 
 
 
 
 449}
 450
 451/*
 452 * Create a new header structure, translate header format from the on-disk
 453 * header.
 454 */
 455static int rbd_header_from_disk(struct rbd_image_header *header,
 456				 struct rbd_image_header_ondisk *ondisk,
 457				 int allocated_snaps,
 458				 gfp_t gfp_flags)
 459{
 460	int i;
 461	u32 snap_count = le32_to_cpu(ondisk->snap_count);
 
 
 
 
 
 462	int ret = -ENOMEM;
 
 463
 464	init_rwsem(&header->snap_rwsem);
 465	header->snap_names_len = le64_to_cpu(ondisk->snap_names_len);
 466	header->snapc = kmalloc(sizeof(struct ceph_snap_context) +
 467				snap_count *
 468				 sizeof(struct rbd_image_snap_ondisk),
 469				gfp_flags);
 470	if (!header->snapc)
 471		return -ENOMEM;
 472	if (snap_count) {
 473		header->snap_names = kmalloc(header->snap_names_len,
 474					     GFP_KERNEL);
 475		if (!header->snap_names)
 476			goto err_snapc;
 477		header->snap_sizes = kmalloc(snap_count * sizeof(u64),
 478					     GFP_KERNEL);
 479		if (!header->snap_sizes)
 480			goto err_names;
 481	} else {
 482		header->snap_names = NULL;
 483		header->snap_sizes = NULL;
 484	}
 485	memcpy(header->block_name, ondisk->block_name,
 486	       sizeof(ondisk->block_name));
 487
 488	header->image_size = le64_to_cpu(ondisk->image_size);
 489	header->obj_order = ondisk->options.order;
 490	header->crypt_type = ondisk->options.crypt_type;
 491	header->comp_type = ondisk->options.comp_type;
 492
 493	atomic_set(&header->snapc->nref, 1);
 494	header->snap_seq = le64_to_cpu(ondisk->snap_seq);
 495	header->snapc->num_snaps = snap_count;
 496	header->total_snaps = snap_count;
 497
 498	if (snap_count &&
 499	    allocated_snaps == snap_count) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 500		for (i = 0; i < snap_count; i++) {
 501			header->snapc->snaps[i] =
 502				le64_to_cpu(ondisk->snaps[i].id);
 503			header->snap_sizes[i] =
 504				le64_to_cpu(ondisk->snaps[i].image_size);
 505		}
 
 506
 507		/* copy snapshot names */
 508		memcpy(header->snap_names, &ondisk->snaps[i],
 509			header->snap_names_len);
 
 
 
 
 
 
 
 510	}
 511
 
 
 
 
 
 
 
 512	return 0;
 
 
 
 
 
 
 
 513
 514err_names:
 515	kfree(header->snap_names);
 516err_snapc:
 517	kfree(header->snapc);
 518	return ret;
 519}
 520
 521static int snap_index(struct rbd_image_header *header, int snap_num)
 522{
 523	return header->total_snaps - snap_num;
 
 
 
 
 
 
 
 
 
 
 524}
 525
 526static u64 cur_snap_id(struct rbd_device *rbd_dev)
 
 
 
 
 527{
 528	struct rbd_image_header *header = &rbd_dev->header;
 
 529
 530	if (!rbd_dev->cur_snap)
 531		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 532
 533	return header->snapc->snaps[snap_index(header, rbd_dev->cur_snap)];
 534}
 535
 536static int snap_by_name(struct rbd_image_header *header, const char *snap_name,
 537			u64 *seq, u64 *size)
 538{
 539	int i;
 540	char *p = header->snap_names;
 541
 542	for (i = 0; i < header->total_snaps; i++, p += strlen(p) + 1) {
 543		if (strcmp(snap_name, p) == 0)
 544			break;
 545	}
 546	if (i == header->total_snaps)
 547		return -ENOENT;
 548	if (seq)
 549		*seq = header->snapc->snaps[i];
 550
 551	if (size)
 552		*size = header->snap_sizes[i];
 
 553
 554	return i;
 
 
 
 
 
 
 
 
 
 555}
 556
 557static int rbd_header_set_snap(struct rbd_device *dev,
 558			       const char *snap_name,
 559			       u64 *size)
 560{
 561	struct rbd_image_header *header = &dev->header;
 562	struct ceph_snap_context *snapc = header->snapc;
 563	int ret = -ENOENT;
 
 
 564
 565	down_write(&header->snap_rwsem);
 
 
 566
 567	if (!snap_name ||
 568	    !*snap_name ||
 569	    strcmp(snap_name, "-") == 0 ||
 570	    strcmp(snap_name, RBD_SNAP_HEAD_NAME) == 0) {
 571		if (header->total_snaps)
 572			snapc->seq = header->snap_seq;
 573		else
 574			snapc->seq = 0;
 575		dev->cur_snap = 0;
 576		dev->read_only = 0;
 577		if (size)
 578			*size = header->image_size;
 579	} else {
 580		ret = snap_by_name(header, snap_name, &snapc->seq, size);
 581		if (ret < 0)
 582			goto done;
 
 
 
 583
 584		dev->cur_snap = header->total_snaps - ret;
 585		dev->read_only = 1;
 586	}
 
 
 587
 588	ret = 0;
 589done:
 590	up_write(&header->snap_rwsem);
 591	return ret;
 
 
 
 
 
 
 
 
 592}
 593
 594static void rbd_header_free(struct rbd_image_header *header)
 595{
 596	kfree(header->snapc);
 597	kfree(header->snap_names);
 598	kfree(header->snap_sizes);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 599}
 600
 601/*
 602 * get the actual striped segment name, offset and length
 
 
 
 603 */
 604static u64 rbd_get_segment(struct rbd_image_header *header,
 605			   const char *block_name,
 606			   u64 ofs, u64 len,
 607			   char *seg_name, u64 *segofs)
 608{
 609	u64 seg = ofs >> header->obj_order;
 
 
 
 
 
 
 
 
 
 
 
 
 
 610
 611	if (seg_name)
 612		snprintf(seg_name, RBD_MAX_SEG_NAME_LEN,
 613			 "%s.%012llx", block_name, seg);
 
 
 
 
 
 614
 615	ofs = ofs & ((1 << header->obj_order) - 1);
 616	len = min_t(u64, len, (1 << header->obj_order) - ofs);
 
 
 617
 618	if (segofs)
 619		*segofs = ofs;
 
 
 620
 621	return len;
 
 
 
 
 
 
 622}
 623
 624static int rbd_get_num_segments(struct rbd_image_header *header,
 625				u64 ofs, u64 len)
 626{
 627	u64 start_seg = ofs >> header->obj_order;
 628	u64 end_seg = (ofs + len - 1) >> header->obj_order;
 629	return end_seg - start_seg + 1;
 
 
 
 630}
 631
 632/*
 633 * returns the size of an object in the image
 
 
 634 */
 635static u64 rbd_obj_bytes(struct rbd_image_header *header)
 636{
 637	return 1 << header->obj_order;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 638}
 639
 640/*
 641 * bio helpers
 642 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 643
 644static void bio_chain_put(struct bio *chain)
 
 
 
 
 
 
 
 
 
 645{
 646	struct bio *tmp;
 
 
 
 
 
 
 
 
 
 
 
 
 
 647
 648	while (chain) {
 649		tmp = chain;
 650		chain = chain->bi_next;
 651		bio_put(tmp);
 
 
 
 
 
 
 652	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 653}
 654
 655/*
 656 * zeros a bio chain, starting at specific offset
 
 
 
 657 */
 658static void zero_bio_chain(struct bio *chain, int start_ofs)
 659{
 660	struct bio_vec *bv;
 661	unsigned long flags;
 662	void *buf;
 663	int i;
 664	int pos = 0;
 665
 666	while (chain) {
 667		bio_for_each_segment(bv, chain, i) {
 668			if (pos + bv->bv_len > start_ofs) {
 669				int remainder = max(start_ofs - pos, 0);
 670				buf = bvec_kmap_irq(bv, &flags);
 671				memset(buf + remainder, 0,
 672				       bv->bv_len - remainder);
 673				bvec_kunmap_irq(buf, &flags);
 674			}
 675			pos += bv->bv_len;
 676		}
 677
 678		chain = chain->bi_next;
 679	}
 
 
 
 
 
 
 
 
 680}
 681
 682/*
 683 * bio_chain_clone - clone a chain of bios up to a certain length.
 684 * might return a bio_pair that will need to be released.
 
 
 
 
 685 */
 686static struct bio *bio_chain_clone(struct bio **old, struct bio **next,
 687				   struct bio_pair **bp,
 688				   int len, gfp_t gfpmask)
 689{
 690	struct bio *tmp, *old_chain = *old, *new_chain = NULL, *tail = NULL;
 691	int total = 0;
 692
 693	if (*bp) {
 694		bio_pair_release(*bp);
 695		*bp = NULL;
 696	}
 697
 698	while (old_chain && (total < len)) {
 699		tmp = bio_kmalloc(gfpmask, old_chain->bi_max_vecs);
 700		if (!tmp)
 701			goto err_out;
 702
 703		if (total + old_chain->bi_size > len) {
 704			struct bio_pair *bp;
 705
 706			/*
 707			 * this split can only happen with a single paged bio,
 708			 * split_bio will BUG_ON if this is not the case
 709			 */
 710			dout("bio_chain_clone split! total=%d remaining=%d"
 711			     "bi_size=%d\n",
 712			     (int)total, (int)len-total,
 713			     (int)old_chain->bi_size);
 714
 715			/* split the bio. We'll release it either in the next
 716			   call, or it will have to be released outside */
 717			bp = bio_split(old_chain, (len - total) / 512ULL);
 718			if (!bp)
 719				goto err_out;
 720
 721			__bio_clone(tmp, &bp->bio1);
 
 
 
 
 722
 723			*next = &bp->bio2;
 724		} else {
 725			__bio_clone(tmp, old_chain);
 726			*next = old_chain->bi_next;
 727		}
 728
 729		tmp->bi_bdev = NULL;
 730		gfpmask &= ~__GFP_WAIT;
 731		tmp->bi_next = NULL;
 
 732
 733		if (!new_chain) {
 734			new_chain = tail = tmp;
 735		} else {
 736			tail->bi_next = tmp;
 737			tail = tmp;
 738		}
 739		old_chain = old_chain->bi_next;
 740
 741		total += tmp->bi_size;
 742	}
 
 
 
 
 743
 744	BUG_ON(total < len);
 
 
 745
 746	if (tail)
 747		tail->bi_next = NULL;
 
 
 748
 749	*old = old_chain;
 750
 751	return new_chain;
 
 
 752
 753err_out:
 754	dout("bio_chain_clone with err\n");
 755	bio_chain_put(new_chain);
 756	return NULL;
 
 
 
 
 757}
 758
 759/*
 760 * helpers for osd request op vectors.
 761 */
 762static int rbd_create_rw_ops(struct ceph_osd_req_op **ops,
 763			    int num_ops,
 764			    int opcode,
 765			    u32 payload_len)
 766{
 767	*ops = kzalloc(sizeof(struct ceph_osd_req_op) * (num_ops + 1),
 768		       GFP_NOIO);
 769	if (!*ops)
 770		return -ENOMEM;
 771	(*ops)[0].op = opcode;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 772	/*
 773	 * op extent offset and length will be set later on
 774	 * in calc_raw_layout()
 
 
 
 
 775	 */
 776	(*ops)[0].payload_len = payload_len;
 777	return 0;
 
 
 
 778}
 779
 780static void rbd_destroy_ops(struct ceph_osd_req_op *ops)
 781{
 782	kfree(ops);
 
 
 
 
 
 
 
 783}
 784
 785static void rbd_coll_end_req_index(struct request *rq,
 786				   struct rbd_req_coll *coll,
 787				   int index,
 788				   int ret, u64 len)
 789{
 790	struct request_queue *q;
 791	int min, max, i;
 
 
 
 
 
 792
 793	dout("rbd_coll_end_req_index %p index %d ret %d len %lld\n",
 794	     coll, index, ret, len);
 
 
 
 
 
 
 
 
 795
 796	if (!rq)
 797		return;
 798
 799	if (!coll) {
 800		blk_end_request(rq, ret, len);
 801		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 802	}
 803
 804	q = rq->q;
 
 
 
 
 
 
 
 
 
 
 
 
 
 805
 806	spin_lock_irq(q->queue_lock);
 807	coll->status[index].done = 1;
 808	coll->status[index].rc = ret;
 809	coll->status[index].bytes = len;
 810	max = min = coll->num_done;
 811	while (max < coll->total && coll->status[max].done)
 812		max++;
 813
 814	for (i = min; i<max; i++) {
 815		__blk_end_request(rq, coll->status[i].rc,
 816				  coll->status[i].bytes);
 817		coll->num_done++;
 818		kref_put(&coll->kref, rbd_coll_release);
 819	}
 820	spin_unlock_irq(q->queue_lock);
 821}
 822
 823static void rbd_coll_end_req(struct rbd_request *req,
 824			     int ret, u64 len)
 825{
 826	rbd_coll_end_req_index(req->rq, req->coll, req->coll_index, ret, len);
 827}
 828
 829/*
 830 * Send ceph osd request
 831 */
 832static int rbd_do_request(struct request *rq,
 833			  struct rbd_device *dev,
 834			  struct ceph_snap_context *snapc,
 835			  u64 snapid,
 836			  const char *obj, u64 ofs, u64 len,
 837			  struct bio *bio,
 838			  struct page **pages,
 839			  int num_pages,
 840			  int flags,
 841			  struct ceph_osd_req_op *ops,
 842			  int num_reply,
 843			  struct rbd_req_coll *coll,
 844			  int coll_index,
 845			  void (*rbd_cb)(struct ceph_osd_request *req,
 846					 struct ceph_msg *msg),
 847			  struct ceph_osd_request **linger_req,
 848			  u64 *ver)
 849{
 850	struct ceph_osd_request *req;
 851	struct ceph_file_layout *layout;
 852	int ret;
 853	u64 bno;
 854	struct timespec mtime = CURRENT_TIME;
 855	struct rbd_request *req_data;
 856	struct ceph_osd_request_head *reqhead;
 857	struct rbd_image_header *header = &dev->header;
 858
 859	req_data = kzalloc(sizeof(*req_data), GFP_NOIO);
 860	if (!req_data) {
 861		if (coll)
 862			rbd_coll_end_req_index(rq, coll, coll_index,
 863					       -ENOMEM, len);
 864		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 865	}
 866
 867	if (coll) {
 868		req_data->coll = coll;
 869		req_data->coll_index = coll_index;
 870	}
 871
 872	dout("rbd_do_request obj=%s ofs=%lld len=%lld\n", obj, len, ofs);
 873
 874	down_read(&header->snap_rwsem);
 875
 876	req = ceph_osdc_alloc_request(&dev->client->osdc, flags,
 877				      snapc,
 878				      ops,
 879				      false,
 880				      GFP_NOIO, pages, bio);
 881	if (!req) {
 882		up_read(&header->snap_rwsem);
 883		ret = -ENOMEM;
 884		goto done_pages;
 885	}
 886
 887	req->r_callback = rbd_cb;
 
 
 888
 889	req_data->rq = rq;
 890	req_data->bio = bio;
 891	req_data->pages = pages;
 892	req_data->len = len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 893
 894	req->r_priv = req_data;
 
 
 
 
 895
 896	reqhead = req->r_request->front.iov_base;
 897	reqhead->snapid = cpu_to_le64(CEPH_NOSNAP);
 898
 899	strncpy(req->r_oid, obj, sizeof(req->r_oid));
 900	req->r_oid_len = strlen(req->r_oid);
 901
 902	layout = &req->r_file_layout;
 903	memset(layout, 0, sizeof(*layout));
 904	layout->fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
 905	layout->fl_stripe_count = cpu_to_le32(1);
 906	layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
 907	layout->fl_pg_preferred = cpu_to_le32(-1);
 908	layout->fl_pg_pool = cpu_to_le32(dev->poolid);
 909	ceph_calc_raw_layout(&dev->client->osdc, layout, snapid,
 910			     ofs, &len, &bno, req, ops);
 911
 912	ceph_osdc_build_request(req, ofs, &len,
 913				ops,
 914				snapc,
 915				&mtime,
 916				req->r_oid, req->r_oid_len);
 917	up_read(&header->snap_rwsem);
 918
 919	if (linger_req) {
 920		ceph_osdc_set_request_linger(&dev->client->osdc, req);
 921		*linger_req = req;
 
 922	}
 923
 924	ret = ceph_osdc_start_request(&dev->client->osdc, req, false);
 925	if (ret < 0)
 926		goto done_err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 927
 928	if (!rbd_cb) {
 929		ret = ceph_osdc_wait_request(&dev->client->osdc, req);
 930		if (ver)
 931			*ver = le64_to_cpu(req->r_reassert_version.version);
 932		dout("reassert_ver=%lld\n",
 933		     le64_to_cpu(req->r_reassert_version.version));
 934		ceph_osdc_put_request(req);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 935	}
 936	return ret;
 937
 938done_err:
 939	bio_chain_put(req_data->bio);
 940	ceph_osdc_put_request(req);
 941done_pages:
 942	rbd_coll_end_req(req_data, ret, len);
 943	kfree(req_data);
 944	return ret;
 945}
 946
 947/*
 948 * Ceph osd op callback
 
 
 
 949 */
 950static void rbd_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg)
 
 951{
 952	struct rbd_request *req_data = req->r_priv;
 953	struct ceph_osd_reply_head *replyhead;
 954	struct ceph_osd_op *op;
 955	__s32 rc;
 956	u64 bytes;
 957	int read_op;
 958
 959	/* parse reply */
 960	replyhead = msg->front.iov_base;
 961	WARN_ON(le32_to_cpu(replyhead->num_ops) == 0);
 962	op = (void *)(replyhead + 1);
 963	rc = le32_to_cpu(replyhead->result);
 964	bytes = le64_to_cpu(op->extent.length);
 965	read_op = (le32_to_cpu(op->op) == CEPH_OSD_OP_READ);
 966
 967	dout("rbd_req_cb bytes=%lld readop=%d rc=%d\n", bytes, read_op, rc);
 
 
 
 
 
 968
 969	if (rc == -ENOENT && read_op) {
 970		zero_bio_chain(req_data->bio, 0);
 971		rc = 0;
 972	} else if (rc == 0 && read_op && bytes < req_data->len) {
 973		zero_bio_chain(req_data->bio, bytes);
 974		bytes = req_data->len;
 
 
 
 
 
 
 
 
 
 
 
 
 975	}
 976
 977	rbd_coll_end_req(req_data, rc, bytes);
 
 
 
 978
 979	if (req_data->bio)
 980		bio_chain_put(req_data->bio);
 
 981
 982	ceph_osdc_put_request(req);
 983	kfree(req_data);
 984}
 985
 986static void rbd_simple_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg)
 
 987{
 988	ceph_osdc_put_request(req);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 989}
 990
 991/*
 992 * Do a synchronous ceph osd operation
 
 993 */
 994static int rbd_req_sync_op(struct rbd_device *dev,
 995			   struct ceph_snap_context *snapc,
 996			   u64 snapid,
 997			   int opcode,
 998			   int flags,
 999			   struct ceph_osd_req_op *orig_ops,
1000			   int num_reply,
1001			   const char *obj,
1002			   u64 ofs, u64 len,
1003			   char *buf,
1004			   struct ceph_osd_request **linger_req,
1005			   u64 *ver)
1006{
 
1007	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1008	struct page **pages;
1009	int num_pages;
1010	struct ceph_osd_req_op *ops = orig_ops;
1011	u32 payload_len;
1012
1013	num_pages = calc_pages_for(ofs , len);
1014	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
 
 
 
 
 
 
 
1015	if (IS_ERR(pages))
1016		return PTR_ERR(pages);
1017
1018	if (!orig_ops) {
1019		payload_len = (flags & CEPH_OSD_FLAG_WRITE ? len : 0);
1020		ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len);
1021		if (ret < 0)
1022			goto done;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1023
1024		if ((flags & CEPH_OSD_FLAG_WRITE) && buf) {
1025			ret = ceph_copy_to_page_vector(pages, buf, ofs, len);
1026			if (ret < 0)
1027				goto done_ops;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1028		}
 
 
1029	}
1030
1031	ret = rbd_do_request(NULL, dev, snapc, snapid,
1032			  obj, ofs, len, NULL,
1033			  pages, num_pages,
1034			  flags,
1035			  ops,
1036			  2,
1037			  NULL, 0,
1038			  NULL,
1039			  linger_req, ver);
1040	if (ret < 0)
1041		goto done_ops;
1042
1043	if ((flags & CEPH_OSD_FLAG_READ) && buf)
1044		ret = ceph_copy_from_page_vector(pages, buf, ofs, ret);
 
1045
1046done_ops:
1047	if (!orig_ops)
1048		rbd_destroy_ops(ops);
1049done:
1050	ceph_release_page_vector(pages, num_pages);
1051	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1052}
1053
1054/*
1055 * Do an asynchronous ceph osd operation
 
 
1056 */
1057static int rbd_do_op(struct request *rq,
1058		     struct rbd_device *rbd_dev ,
1059		     struct ceph_snap_context *snapc,
1060		     u64 snapid,
1061		     int opcode, int flags, int num_reply,
1062		     u64 ofs, u64 len,
1063		     struct bio *bio,
1064		     struct rbd_req_coll *coll,
1065		     int coll_index)
1066{
1067	char *seg_name;
1068	u64 seg_ofs;
1069	u64 seg_len;
1070	int ret;
1071	struct ceph_osd_req_op *ops;
1072	u32 payload_len;
1073
1074	seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO);
1075	if (!seg_name)
1076		return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1077
1078	seg_len = rbd_get_segment(&rbd_dev->header,
1079				  rbd_dev->header.block_name,
1080				  ofs, len,
1081				  seg_name, &seg_ofs);
1082
1083	payload_len = (flags & CEPH_OSD_FLAG_WRITE ? seg_len : 0);
 
 
 
1084
1085	ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len);
1086	if (ret < 0)
1087		goto done;
 
 
 
 
 
1088
1089	/* we've taken care of segment sizes earlier when we
1090	   cloned the bios. We should never have a segment
1091	   truncated at this point */
1092	BUG_ON(seg_len < len);
1093
1094	ret = rbd_do_request(rq, rbd_dev, snapc, snapid,
1095			     seg_name, seg_ofs, seg_len,
1096			     bio,
1097			     NULL, 0,
1098			     flags,
1099			     ops,
1100			     num_reply,
1101			     coll, coll_index,
1102			     rbd_req_cb, 0, NULL);
1103
1104	rbd_destroy_ops(ops);
1105done:
1106	kfree(seg_name);
1107	return ret;
1108}
1109
1110/*
1111 * Request async osd write
 
 
 
 
1112 */
1113static int rbd_req_write(struct request *rq,
1114			 struct rbd_device *rbd_dev,
1115			 struct ceph_snap_context *snapc,
1116			 u64 ofs, u64 len,
1117			 struct bio *bio,
1118			 struct rbd_req_coll *coll,
1119			 int coll_index)
1120{
1121	return rbd_do_op(rq, rbd_dev, snapc, CEPH_NOSNAP,
1122			 CEPH_OSD_OP_WRITE,
1123			 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1124			 2,
1125			 ofs, len, bio, coll, coll_index);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1126}
1127
1128/*
1129 * Request async osd read
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1130 */
1131static int rbd_req_read(struct request *rq,
1132			 struct rbd_device *rbd_dev,
1133			 u64 snapid,
1134			 u64 ofs, u64 len,
1135			 struct bio *bio,
1136			 struct rbd_req_coll *coll,
1137			 int coll_index)
1138{
1139	return rbd_do_op(rq, rbd_dev, NULL,
1140			 (snapid ? snapid : CEPH_NOSNAP),
1141			 CEPH_OSD_OP_READ,
1142			 CEPH_OSD_FLAG_READ,
1143			 2,
1144			 ofs, len, bio, coll, coll_index);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1145}
1146
1147/*
1148 * Request sync osd read
1149 */
1150static int rbd_req_sync_read(struct rbd_device *dev,
1151			  struct ceph_snap_context *snapc,
1152			  u64 snapid,
1153			  const char *obj,
1154			  u64 ofs, u64 len,
1155			  char *buf,
1156			  u64 *ver)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1157{
1158	return rbd_req_sync_op(dev, NULL,
1159			       (snapid ? snapid : CEPH_NOSNAP),
1160			       CEPH_OSD_OP_READ,
1161			       CEPH_OSD_FLAG_READ,
1162			       NULL,
1163			       1, obj, ofs, len, buf, NULL, ver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1164}
1165
1166/*
1167 * Request sync osd watch
 
 
1168 */
1169static int rbd_req_sync_notify_ack(struct rbd_device *dev,
1170				   u64 ver,
1171				   u64 notify_id,
1172				   const char *obj)
1173{
1174	struct ceph_osd_req_op *ops;
1175	struct page **pages = NULL;
1176	int ret;
1177
1178	ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY_ACK, 0);
1179	if (ret < 0)
 
 
 
 
 
 
 
 
 
 
 
 
 
1180		return ret;
1181
1182	ops[0].watch.ver = cpu_to_le64(dev->header.obj_version);
1183	ops[0].watch.cookie = notify_id;
1184	ops[0].watch.flag = 0;
1185
1186	ret = rbd_do_request(NULL, dev, NULL, CEPH_NOSNAP,
1187			  obj, 0, 0, NULL,
1188			  pages, 0,
1189			  CEPH_OSD_FLAG_READ,
1190			  ops,
1191			  1,
1192			  NULL, 0,
1193			  rbd_simple_req_cb, 0, NULL);
1194
1195	rbd_destroy_ops(ops);
1196	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1197}
1198
1199static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1200{
1201	struct rbd_device *dev = (struct rbd_device *)data;
1202	int rc;
 
 
1203
1204	if (!dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1205		return;
 
1206
1207	dout("rbd_watch_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name,
1208		notify_id, (int)opcode);
1209	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
1210	rc = __rbd_update_snaps(dev);
1211	mutex_unlock(&ctl_mutex);
1212	if (rc)
1213		pr_warning(DRV_NAME "%d got notification but failed to update"
1214			   " snaps: %d\n", dev->major, rc);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1215
1216	rbd_req_sync_notify_ack(dev, ver, notify_id, dev->obj_md_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1217}
1218
1219/*
1220 * Request sync osd watch
 
 
 
1221 */
1222static int rbd_req_sync_watch(struct rbd_device *dev,
1223			      const char *obj,
1224			      u64 ver)
1225{
1226	struct ceph_osd_req_op *ops;
1227	struct ceph_osd_client *osdc = &dev->client->osdc;
1228
1229	int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0);
1230	if (ret < 0)
1231		return ret;
1232
1233	ret = ceph_osdc_create_event(osdc, rbd_watch_cb, 0,
1234				     (void *)dev, &dev->watch_event);
1235	if (ret < 0)
1236		goto fail;
1237
1238	ops[0].watch.ver = cpu_to_le64(ver);
1239	ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie);
1240	ops[0].watch.flag = 1;
1241
1242	ret = rbd_req_sync_op(dev, NULL,
1243			      CEPH_NOSNAP,
1244			      0,
1245			      CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1246			      ops,
1247			      1, obj, 0, 0, NULL,
1248			      &dev->watch_request, NULL);
1249
1250	if (ret < 0)
1251		goto fail_event;
 
 
1252
1253	rbd_destroy_ops(ops);
1254	return 0;
 
 
1255
1256fail_event:
1257	ceph_osdc_cancel_event(dev->watch_event);
1258	dev->watch_event = NULL;
1259fail:
1260	rbd_destroy_ops(ops);
1261	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1262}
1263
1264/*
1265 * Request sync osd unwatch
1266 */
1267static int rbd_req_sync_unwatch(struct rbd_device *dev,
1268				const char *obj)
1269{
1270	struct ceph_osd_req_op *ops;
 
 
 
 
 
 
 
 
 
1271
1272	int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0);
1273	if (ret < 0)
1274		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1275
1276	ops[0].watch.ver = 0;
1277	ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie);
1278	ops[0].watch.flag = 0;
1279
1280	ret = rbd_req_sync_op(dev, NULL,
1281			      CEPH_NOSNAP,
1282			      0,
1283			      CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1284			      ops,
1285			      1, obj, 0, 0, NULL, NULL, NULL);
1286
1287	rbd_destroy_ops(ops);
1288	ceph_osdc_cancel_event(dev->watch_event);
1289	dev->watch_event = NULL;
1290	return ret;
 
 
 
 
 
1291}
1292
1293struct rbd_notify_info {
1294	struct rbd_device *dev;
1295};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1296
1297static void rbd_notify_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1298{
1299	struct rbd_device *dev = (struct rbd_device *)data;
1300	if (!dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1301		return;
1302
1303	dout("rbd_notify_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name,
1304		notify_id, (int)opcode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1305}
1306
1307/*
1308 * Request sync osd notify
1309 */
1310static int rbd_req_sync_notify(struct rbd_device *dev,
1311		          const char *obj)
1312{
1313	struct ceph_osd_req_op *ops;
1314	struct ceph_osd_client *osdc = &dev->client->osdc;
1315	struct ceph_osd_event *event;
1316	struct rbd_notify_info info;
1317	int payload_len = sizeof(u32) + sizeof(u32);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1318	int ret;
1319
1320	ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY, payload_len);
1321	if (ret < 0)
 
 
 
 
 
 
1322		return ret;
1323
1324	info.dev = dev;
 
 
1325
1326	ret = ceph_osdc_create_event(osdc, rbd_notify_cb, 1,
1327				     (void *)&info, &event);
1328	if (ret < 0)
1329		goto fail;
 
 
 
1330
1331	ops[0].watch.ver = 1;
1332	ops[0].watch.flag = 1;
1333	ops[0].watch.cookie = event->cookie;
1334	ops[0].watch.prot_ver = RADOS_NOTIFY_VER;
1335	ops[0].watch.timeout = 12;
1336
1337	ret = rbd_req_sync_op(dev, NULL,
1338			       CEPH_NOSNAP,
1339			       0,
1340			       CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1341			       ops,
1342			       1, obj, 0, 0, NULL, NULL, NULL);
1343	if (ret < 0)
1344		goto fail_event;
1345
1346	ret = ceph_osdc_wait_event(event, CEPH_OSD_TIMEOUT_DEFAULT);
1347	dout("ceph_osdc_wait_event returned %d\n", ret);
1348	rbd_destroy_ops(ops);
1349	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1350
1351fail_event:
1352	ceph_osdc_cancel_event(event);
1353fail:
1354	rbd_destroy_ops(ops);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1355	return ret;
 
 
 
 
1356}
1357
1358/*
1359 * Request sync osd rollback
 
1360 */
1361static int rbd_req_sync_rollback_obj(struct rbd_device *dev,
1362				     u64 snapid,
1363				     const char *obj)
1364{
1365	struct ceph_osd_req_op *ops;
1366	int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_ROLLBACK, 0);
1367	if (ret < 0)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1368		return ret;
1369
1370	ops[0].snap.snapid = snapid;
 
 
 
 
 
 
 
 
 
 
1371
1372	ret = rbd_req_sync_op(dev, NULL,
1373			       CEPH_NOSNAP,
1374			       0,
1375			       CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1376			       ops,
1377			       1, obj, 0, 0, NULL, NULL, NULL);
1378
1379	rbd_destroy_ops(ops);
 
 
 
 
 
 
1380
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1381	return ret;
1382}
1383
1384/*
1385 * Request sync osd read
1386 */
1387static int rbd_req_sync_exec(struct rbd_device *dev,
1388			     const char *obj,
1389			     const char *cls,
1390			     const char *method,
1391			     const char *data,
1392			     int len,
1393			     u64 *ver)
1394{
1395	struct ceph_osd_req_op *ops;
1396	int cls_len = strlen(cls);
1397	int method_len = strlen(method);
1398	int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_CALL,
1399				    cls_len + method_len + len);
1400	if (ret < 0)
1401		return ret;
 
 
 
 
 
 
 
 
 
 
1402
1403	ops[0].cls.class_name = cls;
1404	ops[0].cls.class_len = (__u8)cls_len;
1405	ops[0].cls.method_name = method;
1406	ops[0].cls.method_len = (__u8)method_len;
1407	ops[0].cls.argc = 0;
1408	ops[0].cls.indata = data;
1409	ops[0].cls.indata_len = len;
 
 
 
 
 
 
 
1410
1411	ret = rbd_req_sync_op(dev, NULL,
1412			       CEPH_NOSNAP,
1413			       0,
1414			       CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1415			       ops,
1416			       1, obj, 0, 0, NULL, NULL, ver);
1417
1418	rbd_destroy_ops(ops);
 
 
1419
1420	dout("cls_exec returned %d\n", ret);
 
1421	return ret;
1422}
1423
1424static struct rbd_req_coll *rbd_alloc_coll(int num_reqs)
1425{
1426	struct rbd_req_coll *coll =
1427			kzalloc(sizeof(struct rbd_req_coll) +
1428			        sizeof(struct rbd_req_status) * num_reqs,
1429				GFP_ATOMIC);
1430
1431	if (!coll)
1432		return NULL;
1433	coll->total = num_reqs;
1434	kref_init(&coll->kref);
1435	return coll;
 
 
1436}
1437
1438/*
1439 * block device queue callback
 
 
 
1440 */
1441static void rbd_rq_fn(struct request_queue *q)
1442{
1443	struct rbd_device *rbd_dev = q->queuedata;
1444	struct request *rq;
1445	struct bio_pair *bp = NULL;
1446
1447	rq = blk_fetch_request(q);
 
 
 
 
 
 
1448
1449	while (1) {
1450		struct bio *bio;
1451		struct bio *rq_bio, *next_bio = NULL;
1452		bool do_write;
1453		int size, op_size = 0;
1454		u64 ofs;
1455		int num_segs, cur_seg = 0;
1456		struct rbd_req_coll *coll;
1457
1458		/* peek at request from block layer */
1459		if (!rq)
1460			break;
 
 
1461
1462		dout("fetched request\n");
 
 
 
 
 
1463
1464		/* filter out block requests we don't understand */
1465		if ((rq->cmd_type != REQ_TYPE_FS)) {
1466			__blk_end_request_all(rq, 0);
1467			goto next;
1468		}
1469
1470		/* deduce our operation (read, write) */
1471		do_write = (rq_data_dir(rq) == WRITE);
1472
1473		size = blk_rq_bytes(rq);
1474		ofs = blk_rq_pos(rq) * 512ULL;
1475		rq_bio = rq->bio;
1476		if (do_write && rbd_dev->read_only) {
1477			__blk_end_request_all(rq, -EROFS);
1478			goto next;
1479		}
1480
1481		spin_unlock_irq(q->queue_lock);
1482
1483		dout("%s 0x%x bytes at 0x%llx\n",
1484		     do_write ? "write" : "read",
1485		     size, blk_rq_pos(rq) * 512ULL);
1486
1487		num_segs = rbd_get_num_segments(&rbd_dev->header, ofs, size);
1488		coll = rbd_alloc_coll(num_segs);
1489		if (!coll) {
1490			spin_lock_irq(q->queue_lock);
1491			__blk_end_request_all(rq, -ENOMEM);
1492			goto next;
1493		}
1494
1495		do {
1496			/* a bio clone to be passed down to OSD req */
1497			dout("rq->bio->bi_vcnt=%d\n", rq->bio->bi_vcnt);
1498			op_size = rbd_get_segment(&rbd_dev->header,
1499						  rbd_dev->header.block_name,
1500						  ofs, size,
1501						  NULL, NULL);
1502			kref_get(&coll->kref);
1503			bio = bio_chain_clone(&rq_bio, &next_bio, &bp,
1504					      op_size, GFP_ATOMIC);
1505			if (!bio) {
1506				rbd_coll_end_req_index(rq, coll, cur_seg,
1507						       -ENOMEM, op_size);
1508				goto next_seg;
1509			}
1510
 
 
 
 
 
 
 
 
 
 
1511
1512			/* init OSD command: write or read */
1513			if (do_write)
1514				rbd_req_write(rq, rbd_dev,
1515					      rbd_dev->header.snapc,
1516					      ofs,
1517					      op_size, bio,
1518					      coll, cur_seg);
1519			else
1520				rbd_req_read(rq, rbd_dev,
1521					     cur_snap_id(rbd_dev),
1522					     ofs,
1523					     op_size, bio,
1524					     coll, cur_seg);
1525
1526next_seg:
1527			size -= op_size;
1528			ofs += op_size;
1529
1530			cur_seg++;
1531			rq_bio = next_bio;
1532		} while (size > 0);
1533		kref_put(&coll->kref, rbd_coll_release);
1534
1535		if (bp)
1536			bio_pair_release(bp);
1537		spin_lock_irq(q->queue_lock);
1538next:
1539		rq = blk_fetch_request(q);
1540	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1541}
1542
1543/*
1544 * a queue callback. Makes sure that we don't create a bio that spans across
1545 * multiple osd objects. One exception would be with a single page bios,
1546 * which we handle later at bio_chain_clone
1547 */
1548static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
1549			  struct bio_vec *bvec)
1550{
1551	struct rbd_device *rbd_dev = q->queuedata;
1552	unsigned int chunk_sectors = 1 << (rbd_dev->header.obj_order - 9);
1553	sector_t sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev);
1554	unsigned int bio_sectors = bmd->bi_size >> 9;
1555	int max;
1556
1557	max =  (chunk_sectors - ((sector & (chunk_sectors - 1))
1558				 + bio_sectors)) << 9;
1559	if (max < 0)
1560		max = 0; /* bio_add cannot handle a negative return */
1561	if (max <= bvec->bv_len && bio_sectors == 0)
1562		return bvec->bv_len;
1563	return max;
1564}
1565
1566static void rbd_free_disk(struct rbd_device *rbd_dev)
 
 
 
 
 
 
 
 
 
 
1567{
1568	struct gendisk *disk = rbd_dev->disk;
1569
1570	if (!disk)
 
1571		return;
1572
1573	rbd_header_free(&rbd_dev->header);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1574
1575	if (disk->flags & GENHD_FL_UP)
1576		del_gendisk(disk);
1577	if (disk->queue)
1578		blk_cleanup_queue(disk->queue);
1579	put_disk(disk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1580}
1581
1582/*
1583 * reload the ondisk the header 
 
1584 */
1585static int rbd_read_header(struct rbd_device *rbd_dev,
1586			   struct rbd_image_header *header)
1587{
1588	ssize_t rc;
1589	struct rbd_image_header_ondisk *dh;
1590	int snap_count = 0;
1591	u64 snap_names_len = 0;
1592	u64 ver;
1593
1594	while (1) {
1595		int len = sizeof(*dh) +
1596			  snap_count * sizeof(struct rbd_image_snap_ondisk) +
1597			  snap_names_len;
1598
1599		rc = -ENOMEM;
1600		dh = kmalloc(len, GFP_KERNEL);
1601		if (!dh)
1602			return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1603
1604		rc = rbd_req_sync_read(rbd_dev,
1605				       NULL, CEPH_NOSNAP,
1606				       rbd_dev->obj_md_name,
1607				       0, len,
1608				       (char *)dh, &ver);
1609		if (rc < 0)
1610			goto out_dh;
1611
1612		rc = rbd_header_from_disk(header, dh, snap_count, GFP_KERNEL);
1613		if (rc < 0)
1614			goto out_dh;
1615
1616		if (snap_count != header->total_snaps) {
1617			snap_count = header->total_snaps;
1618			snap_names_len = header->snap_names_len;
1619			rbd_header_free(header);
1620			kfree(dh);
1621			continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1622		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1623		break;
1624	}
1625	header->obj_version = ver;
1626
1627out_dh:
1628	kfree(dh);
1629	return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1630}
1631
1632/*
1633 * create a snapshot
1634 */
1635static int rbd_header_add_snap(struct rbd_device *dev,
1636			       const char *snap_name,
1637			       gfp_t gfp_flags)
1638{
1639	int name_len = strlen(snap_name);
1640	u64 new_snapid;
1641	int ret;
1642	void *data, *p, *e;
1643	u64 ver;
1644
1645	/* we should create a snapshot only if we're pointing at the head */
1646	if (dev->cur_snap)
1647		return -EINVAL;
1648
1649	ret = ceph_monc_create_snapid(&dev->client->monc, dev->poolid,
1650				      &new_snapid);
1651	dout("created snapid=%lld\n", new_snapid);
1652	if (ret < 0)
1653		return ret;
1654
1655	data = kmalloc(name_len + 16, gfp_flags);
1656	if (!data)
1657		return -ENOMEM;
1658
1659	p = data;
1660	e = data + name_len + 16;
 
 
 
 
 
1661
1662	ceph_encode_string_safe(&p, e, snap_name, name_len, bad);
1663	ceph_encode_64_safe(&p, e, new_snapid, bad);
1664
1665	ret = rbd_req_sync_exec(dev, dev->obj_md_name, "rbd", "snap_add",
1666				data, p - data, &ver);
 
1667
1668	kfree(data);
 
1669
1670	if (ret < 0)
1671		return ret;
 
1672
1673	dev->header.snapc->seq =  new_snapid;
 
 
 
 
1674
1675	return 0;
1676bad:
1677	return -ERANGE;
 
 
 
1678}
1679
1680static void __rbd_remove_all_snaps(struct rbd_device *rbd_dev)
1681{
1682	struct rbd_snap *snap;
1683
1684	while (!list_empty(&rbd_dev->snaps)) {
1685		snap = list_first_entry(&rbd_dev->snaps, struct rbd_snap, node);
1686		__rbd_remove_snap_dev(rbd_dev, snap);
1687	}
1688}
1689
1690/*
1691 * only read the first part of the ondisk header, without the snaps info
 
1692 */
1693static int __rbd_update_snaps(struct rbd_device *rbd_dev)
1694{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1695	int ret;
1696	struct rbd_image_header h;
1697	u64 snap_seq;
1698	int follow_seq = 0;
1699
1700	ret = rbd_read_header(rbd_dev, &h);
1701	if (ret < 0)
1702		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1703
1704	/* resized? */
1705	set_capacity(rbd_dev->disk, h.image_size / 512ULL);
 
 
 
 
 
 
 
 
 
1706
1707	down_write(&rbd_dev->header.snap_rwsem);
 
1708
1709	snap_seq = rbd_dev->header.snapc->seq;
1710	if (rbd_dev->header.total_snaps &&
1711	    rbd_dev->header.snapc->snaps[0] == snap_seq)
1712		/* pointing at the head, will need to follow that
1713		   if head moves */
1714		follow_seq = 1;
1715
1716	kfree(rbd_dev->header.snapc);
1717	kfree(rbd_dev->header.snap_names);
1718	kfree(rbd_dev->header.snap_sizes);
1719
1720	rbd_dev->header.total_snaps = h.total_snaps;
1721	rbd_dev->header.snapc = h.snapc;
1722	rbd_dev->header.snap_names = h.snap_names;
1723	rbd_dev->header.snap_names_len = h.snap_names_len;
1724	rbd_dev->header.snap_sizes = h.snap_sizes;
1725	if (follow_seq)
1726		rbd_dev->header.snapc->seq = rbd_dev->header.snapc->snaps[0];
1727	else
1728		rbd_dev->header.snapc->seq = snap_seq;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1729
1730	ret = __rbd_init_snaps_header(rbd_dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1731
1732	up_write(&rbd_dev->header.snap_rwsem);
 
 
 
1733
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1734	return ret;
1735}
1736
1737static int rbd_init_disk(struct rbd_device *rbd_dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1738{
1739	struct gendisk *disk;
1740	struct request_queue *q;
1741	int rc;
1742	u64 total_size = 0;
1743
1744	/* contact OSD, request size info about the object being mapped */
1745	rc = rbd_read_header(rbd_dev, &rbd_dev->header);
1746	if (rc)
1747		return rc;
 
 
 
 
 
 
 
 
1748
1749	/* no need to lock here, as rbd_dev is not registered yet */
1750	rc = __rbd_init_snaps_header(rbd_dev);
1751	if (rc)
1752		return rc;
1753
1754	rc = rbd_header_set_snap(rbd_dev, rbd_dev->snap_name, &total_size);
1755	if (rc)
1756		return rc;
1757
1758	/* create gendisk info */
1759	rc = -ENOMEM;
1760	disk = alloc_disk(RBD_MINORS_PER_MAJOR);
1761	if (!disk)
1762		goto out;
1763
1764	snprintf(disk->disk_name, sizeof(disk->disk_name), DRV_NAME "%d",
1765		 rbd_dev->id);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1766	disk->major = rbd_dev->major;
1767	disk->first_minor = 0;
 
 
 
 
 
 
1768	disk->fops = &rbd_bd_ops;
1769	disk->private_data = rbd_dev;
1770
1771	/* init rq */
1772	rc = -ENOMEM;
1773	q = blk_init_queue(rbd_rq_fn, &rbd_dev->lock);
1774	if (!q)
1775		goto out_disk;
1776
1777	/* set io sizes to object size */
1778	blk_queue_max_hw_sectors(q, rbd_obj_bytes(&rbd_dev->header) / 512ULL);
1779	blk_queue_max_segment_size(q, rbd_obj_bytes(&rbd_dev->header));
1780	blk_queue_io_min(q, rbd_obj_bytes(&rbd_dev->header));
1781	blk_queue_io_opt(q, rbd_obj_bytes(&rbd_dev->header));
1782
1783	blk_queue_merge_bvec(q, rbd_merge_bvec);
1784	disk->queue = q;
 
 
 
 
 
 
 
 
 
 
 
1785
1786	q->queuedata = rbd_dev;
 
1787
1788	rbd_dev->disk = disk;
1789	rbd_dev->q = q;
1790
1791	/* finally, announce the disk to the world */
1792	set_capacity(disk, total_size / 512ULL);
1793	add_disk(disk);
1794
1795	pr_info("%s: added with size 0x%llx\n",
1796		disk->disk_name, (unsigned long long)total_size);
1797	return 0;
1798
1799out_disk:
1800	put_disk(disk);
1801out:
1802	return rc;
1803}
1804
1805/*
1806  sysfs
1807*/
1808
 
 
 
 
 
1809static ssize_t rbd_size_show(struct device *dev,
1810			     struct device_attribute *attr, char *buf)
1811{
1812	struct rbd_device *rbd_dev = dev_to_rbd(dev);
1813
1814	return sprintf(buf, "%llu\n", (unsigned long long)rbd_dev->header.image_size);
 
 
 
 
 
 
 
 
 
1815}
1816
1817static ssize_t rbd_major_show(struct device *dev,
1818			      struct device_attribute *attr, char *buf)
1819{
1820	struct rbd_device *rbd_dev = dev_to_rbd(dev);
 
 
 
 
 
 
 
 
 
 
 
1821
1822	return sprintf(buf, "%d\n", rbd_dev->major);
 
 
 
 
 
 
 
 
 
 
 
1823}
1824
1825static ssize_t rbd_client_id_show(struct device *dev,
1826				  struct device_attribute *attr, char *buf)
1827{
1828	struct rbd_device *rbd_dev = dev_to_rbd(dev);
 
 
 
 
 
 
 
 
 
1829
1830	return sprintf(buf, "client%lld\n", ceph_client_id(rbd_dev->client));
 
 
 
 
 
 
 
 
 
 
 
1831}
1832
1833static ssize_t rbd_pool_show(struct device *dev,
1834			     struct device_attribute *attr, char *buf)
1835{
1836	struct rbd_device *rbd_dev = dev_to_rbd(dev);
1837
1838	return sprintf(buf, "%s\n", rbd_dev->pool_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1839}
1840
1841static ssize_t rbd_name_show(struct device *dev,
1842			     struct device_attribute *attr, char *buf)
1843{
1844	struct rbd_device *rbd_dev = dev_to_rbd(dev);
 
 
 
1845
1846	return sprintf(buf, "%s\n", rbd_dev->obj);
1847}
1848
 
 
 
 
 
 
 
 
 
 
 
 
1849static ssize_t rbd_snap_show(struct device *dev,
1850			     struct device_attribute *attr,
1851			     char *buf)
1852{
1853	struct rbd_device *rbd_dev = dev_to_rbd(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1854
1855	return sprintf(buf, "%s\n", rbd_dev->snap_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1856}
1857
1858static ssize_t rbd_image_refresh(struct device *dev,
1859				 struct device_attribute *attr,
1860				 const char *buf,
1861				 size_t size)
1862{
1863	struct rbd_device *rbd_dev = dev_to_rbd(dev);
1864	int rc;
1865	int ret = size;
1866
1867	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
1868
1869	rc = __rbd_update_snaps(rbd_dev);
1870	if (rc < 0)
1871		ret = rc;
1872
1873	mutex_unlock(&ctl_mutex);
1874	return ret;
1875}
1876
1877static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
1878static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
1879static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
1880static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
1881static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
1882static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
1883static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
1884static DEVICE_ATTR(create_snap, S_IWUSR, NULL, rbd_snap_add);
1885static DEVICE_ATTR(rollback_snap, S_IWUSR, NULL, rbd_snap_rollback);
 
 
 
 
 
 
 
 
1886
1887static struct attribute *rbd_attrs[] = {
1888	&dev_attr_size.attr,
 
1889	&dev_attr_major.attr,
 
 
1890	&dev_attr_client_id.attr,
 
 
1891	&dev_attr_pool.attr,
 
 
1892	&dev_attr_name.attr,
 
1893	&dev_attr_current_snap.attr,
 
 
1894	&dev_attr_refresh.attr,
1895	&dev_attr_create_snap.attr,
1896	&dev_attr_rollback_snap.attr,
1897	NULL
1898};
1899
1900static struct attribute_group rbd_attr_group = {
1901	.attrs = rbd_attrs,
1902};
1903
1904static const struct attribute_group *rbd_attr_groups[] = {
1905	&rbd_attr_group,
1906	NULL
1907};
1908
1909static void rbd_sysfs_dev_release(struct device *dev)
1910{
1911}
1912
1913static struct device_type rbd_device_type = {
1914	.name		= "rbd",
1915	.groups		= rbd_attr_groups,
1916	.release	= rbd_sysfs_dev_release,
1917};
1918
 
 
 
1919
1920/*
1921  sysfs - snapshots
1922*/
1923
1924static ssize_t rbd_snap_size_show(struct device *dev,
1925				  struct device_attribute *attr,
1926				  char *buf)
1927{
1928	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
 
 
1929
1930	return sprintf(buf, "%lld\n", (long long)snap->size);
 
 
 
 
 
 
 
 
 
 
 
 
1931}
1932
1933static ssize_t rbd_snap_id_show(struct device *dev,
1934				struct device_attribute *attr,
1935				char *buf)
1936{
1937	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
1938
1939	return sprintf(buf, "%lld\n", (long long)snap->id);
 
 
 
 
 
1940}
1941
1942static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
1943static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
 
 
1944
1945static struct attribute *rbd_snap_attrs[] = {
1946	&dev_attr_snap_size.attr,
1947	&dev_attr_snap_id.attr,
1948	NULL,
1949};
1950
1951static struct attribute_group rbd_snap_attr_group = {
1952	.attrs = rbd_snap_attrs,
1953};
 
 
1954
1955static void rbd_snap_dev_release(struct device *dev)
1956{
1957	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
1958	kfree(snap->name);
1959	kfree(snap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1960}
1961
1962static const struct attribute_group *rbd_snap_attr_groups[] = {
1963	&rbd_snap_attr_group,
1964	NULL
1965};
1966
1967static struct device_type rbd_snap_device_type = {
1968	.groups		= rbd_snap_attr_groups,
1969	.release	= rbd_snap_dev_release,
1970};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1971
1972static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev,
1973				  struct rbd_snap *snap)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1974{
1975	list_del(&snap->node);
1976	device_unregister(&snap->dev);
1977}
1978
1979static int rbd_register_snap_dev(struct rbd_device *rbd_dev,
1980				  struct rbd_snap *snap,
1981				  struct device *parent)
 
 
 
 
1982{
1983	struct device *dev = &snap->dev;
1984	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1985
1986	dev->type = &rbd_snap_device_type;
1987	dev->parent = parent;
1988	dev->release = rbd_snap_dev_release;
1989	dev_set_name(dev, "snap_%s", snap->name);
1990	ret = device_register(dev);
1991
1992	return ret;
 
 
 
 
 
 
 
 
 
 
 
1993}
1994
1995static int __rbd_add_snap_dev(struct rbd_device *rbd_dev,
1996			      int i, const char *name,
1997			      struct rbd_snap **snapp)
1998{
 
 
1999	int ret;
2000	struct rbd_snap *snap = kzalloc(sizeof(*snap), GFP_KERNEL);
2001	if (!snap)
 
 
 
 
2002		return -ENOMEM;
2003	snap->name = kstrdup(name, GFP_KERNEL);
2004	snap->size = rbd_dev->header.snap_sizes[i];
2005	snap->id = rbd_dev->header.snapc->snaps[i];
2006	if (device_is_registered(&rbd_dev->dev)) {
2007		ret = rbd_register_snap_dev(rbd_dev, snap,
2008					     &rbd_dev->dev);
2009		if (ret < 0)
2010			goto err;
 
 
 
 
 
 
 
 
 
 
2011	}
2012	*snapp = snap;
2013	return 0;
2014err:
2015	kfree(snap->name);
2016	kfree(snap);
2017	return ret;
2018}
2019
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2020/*
2021 * search for the previous snap in a null delimited string list
 
 
 
 
2022 */
2023const char *rbd_prev_snap_name(const char *name, const char *start)
2024{
2025	if (name < start + 2)
2026		return NULL;
 
2027
2028	name -= 2;
2029	while (*name) {
2030		if (name == start)
2031			return start;
2032		name--;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2033	}
2034	return name + 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2035}
2036
2037/*
2038 * compare the old list of snapshots that we have to what's in the header
2039 * and update it accordingly. Note that the header holds the snapshots
2040 * in a reverse order (from newest to oldest) and we need to go from
2041 * older to new so that we don't get a duplicate snap name when
2042 * doing the process (e.g., removed snapshot and recreated a new
2043 * one with the same name.
2044 */
2045static int __rbd_init_snaps_header(struct rbd_device *rbd_dev)
 
 
 
2046{
2047	const char *name, *first_name;
2048	int i = rbd_dev->header.total_snaps;
2049	struct rbd_snap *snap, *old_snap = NULL;
2050	int ret;
2051	struct list_head *p, *n;
2052
2053	first_name = rbd_dev->header.snap_names;
2054	name = first_name + rbd_dev->header.snap_names_len;
 
 
 
2055
2056	list_for_each_prev_safe(p, n, &rbd_dev->snaps) {
2057		u64 cur_id;
 
 
 
 
 
 
 
 
 
 
2058
2059		old_snap = list_entry(p, struct rbd_snap, node);
2060
2061		if (i)
2062			cur_id = rbd_dev->header.snapc->snaps[i - 1];
 
2063
2064		if (!i || old_snap->id < cur_id) {
2065			/* old_snap->id was skipped, thus was removed */
2066			__rbd_remove_snap_dev(rbd_dev, old_snap);
2067			continue;
2068		}
2069		if (old_snap->id == cur_id) {
2070			/* we have this snapshot already */
2071			i--;
2072			name = rbd_prev_snap_name(name, first_name);
2073			continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2074		}
2075		for (; i > 0;
2076		     i--, name = rbd_prev_snap_name(name, first_name)) {
2077			if (!name) {
2078				WARN_ON(1);
2079				return -EINVAL;
2080			}
2081			cur_id = rbd_dev->header.snapc->snaps[i];
2082			/* snapshot removal? handle it above */
2083			if (cur_id >= old_snap->id)
2084				break;
2085			/* a new snapshot */
2086			ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap);
2087			if (ret < 0)
2088				return ret;
2089
2090			/* note that we add it backward so using n and not p */
2091			list_add(&snap->node, n);
2092			p = &snap->node;
 
 
 
 
 
2093		}
 
 
 
 
 
 
2094	}
2095	/* we're done going over the old snap list, just add what's left */
2096	for (; i > 0; i--) {
2097		name = rbd_prev_snap_name(name, first_name);
2098		if (!name) {
2099			WARN_ON(1);
2100			return -EINVAL;
 
 
 
 
 
 
 
 
2101		}
2102		ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap);
2103		if (ret < 0)
2104			return ret;
2105		list_add(&snap->node, &rbd_dev->snaps);
2106	}
 
2107
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2108	return 0;
2109}
2110
 
 
 
 
 
 
 
 
 
 
 
 
2111
2112static void rbd_root_dev_release(struct device *dev)
 
 
 
 
 
2113{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2114}
2115
2116static struct device rbd_root_dev = {
2117	.init_name =    "rbd",
2118	.release =      rbd_root_dev_release,
2119};
 
 
 
2120
2121static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
 
 
 
 
 
 
 
 
 
 
2122{
2123	int ret = -ENOMEM;
2124	struct device *dev;
2125	struct rbd_snap *snap;
 
2126
2127	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2128	dev = &rbd_dev->dev;
2129
2130	dev->bus = &rbd_bus_type;
2131	dev->type = &rbd_device_type;
2132	dev->parent = &rbd_root_dev;
2133	dev->release = rbd_dev_release;
2134	dev_set_name(dev, "%d", rbd_dev->id);
2135	ret = device_register(dev);
2136	if (ret < 0)
2137		goto done_free;
 
 
 
 
 
 
2138
2139	list_for_each_entry(snap, &rbd_dev->snaps, node) {
2140		ret = rbd_register_snap_dev(rbd_dev, snap,
2141					     &rbd_dev->dev);
2142		if (ret < 0)
2143			break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2144	}
2145
2146	mutex_unlock(&ctl_mutex);
2147	return 0;
2148done_free:
2149	mutex_unlock(&ctl_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2150	return ret;
2151}
2152
2153static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
2154{
2155	device_unregister(&rbd_dev->dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2156}
2157
2158static int rbd_init_watch_dev(struct rbd_device *rbd_dev)
 
2159{
2160	int ret, rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2161
2162	do {
2163		ret = rbd_req_sync_watch(rbd_dev, rbd_dev->obj_md_name,
2164					 rbd_dev->header.obj_version);
2165		if (ret == -ERANGE) {
2166			mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2167			rc = __rbd_update_snaps(rbd_dev);
2168			mutex_unlock(&ctl_mutex);
2169			if (rc < 0)
2170				return rc;
2171		}
2172	} while (ret == -ERANGE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2173
2174	return ret;
2175}
2176
2177static ssize_t rbd_add(struct bus_type *bus,
2178		       const char *buf,
2179		       size_t count)
2180{
2181	struct ceph_osd_client *osdc;
2182	struct rbd_device *rbd_dev;
2183	ssize_t rc = -ENOMEM;
2184	int irc, new_id = 0;
2185	struct list_head *tmp;
2186	char *mon_dev_name;
2187	char *options;
2188
2189	if (!try_module_get(THIS_MODULE))
2190		return -ENODEV;
2191
2192	mon_dev_name = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
2193	if (!mon_dev_name)
2194		goto err_out_mod;
2195
2196	options = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
2197	if (!options)
2198		goto err_mon_dev;
 
 
 
 
 
 
 
 
 
 
2199
2200	/* new rbd_device object */
2201	rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
2202	if (!rbd_dev)
2203		goto err_out_opt;
2204
2205	/* static rbd_device initialization */
2206	spin_lock_init(&rbd_dev->lock);
2207	INIT_LIST_HEAD(&rbd_dev->node);
2208	INIT_LIST_HEAD(&rbd_dev->snaps);
2209
2210	/* generate unique id: find highest unique id, add one */
2211	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2212
2213	list_for_each(tmp, &rbd_dev_list) {
2214		struct rbd_device *rbd_dev;
 
 
 
 
2215
2216		rbd_dev = list_entry(tmp, struct rbd_device, node);
2217		if (rbd_dev->id >= new_id)
2218			new_id = rbd_dev->id + 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2219	}
2220
2221	rbd_dev->id = new_id;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2222
2223	/* add to global list */
2224	list_add_tail(&rbd_dev->node, &rbd_dev_list);
2225
2226	/* parse add command */
2227	if (sscanf(buf, "%" __stringify(RBD_MAX_OPT_LEN) "s "
2228		   "%" __stringify(RBD_MAX_OPT_LEN) "s "
2229		   "%" __stringify(RBD_MAX_POOL_NAME_LEN) "s "
2230		   "%" __stringify(RBD_MAX_OBJ_NAME_LEN) "s"
2231		   "%" __stringify(RBD_MAX_SNAP_NAME_LEN) "s",
2232		   mon_dev_name, options, rbd_dev->pool_name,
2233		   rbd_dev->obj, rbd_dev->snap_name) < 4) {
2234		rc = -EINVAL;
2235		goto err_out_slot;
2236	}
2237
2238	if (rbd_dev->snap_name[0] == 0)
2239		rbd_dev->snap_name[0] = '-';
2240
2241	rbd_dev->obj_len = strlen(rbd_dev->obj);
2242	snprintf(rbd_dev->obj_md_name, sizeof(rbd_dev->obj_md_name), "%s%s",
2243		 rbd_dev->obj, RBD_SUFFIX);
2244
2245	/* initialize rest of new object */
2246	snprintf(rbd_dev->name, DEV_NAME_LEN, DRV_NAME "%d", rbd_dev->id);
2247	rc = rbd_get_client(rbd_dev, mon_dev_name, options);
2248	if (rc < 0)
2249		goto err_out_slot;
2250
2251	mutex_unlock(&ctl_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2252
2253	/* pick the pool */
2254	osdc = &rbd_dev->client->osdc;
2255	rc = ceph_pg_poolid_by_name(osdc->osdmap, rbd_dev->pool_name);
2256	if (rc < 0)
2257		goto err_out_client;
2258	rbd_dev->poolid = rc;
2259
2260	/* register our block device */
2261	irc = register_blkdev(0, rbd_dev->name);
2262	if (irc < 0) {
2263		rc = irc;
2264		goto err_out_client;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2265	}
2266	rbd_dev->major = irc;
 
 
2267
2268	rc = rbd_bus_add_dev(rbd_dev);
2269	if (rc)
2270		goto err_out_blkdev;
 
 
 
 
 
2271
2272	/* set up and announce blkdev mapping */
2273	rc = rbd_init_disk(rbd_dev);
2274	if (rc)
2275		goto err_out_bus;
 
 
 
 
 
 
 
2276
2277	rc = rbd_init_watch_dev(rbd_dev);
2278	if (rc)
2279		goto err_out_bus;
 
 
 
 
2280
2281	return count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2282
2283err_out_bus:
2284	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2285	list_del_init(&rbd_dev->node);
2286	mutex_unlock(&ctl_mutex);
2287
2288	/* this will also clean up rest of rbd_dev stuff */
 
 
2289
2290	rbd_bus_del_dev(rbd_dev);
 
 
2291	kfree(options);
2292	kfree(mon_dev_name);
2293	return rc;
2294
2295err_out_blkdev:
2296	unregister_blkdev(rbd_dev->major, rbd_dev->name);
2297err_out_client:
2298	rbd_put_client(rbd_dev);
2299	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2300err_out_slot:
2301	list_del_init(&rbd_dev->node);
2302	mutex_unlock(&ctl_mutex);
2303
2304	kfree(rbd_dev);
2305err_out_opt:
 
 
 
 
2306	kfree(options);
2307err_mon_dev:
2308	kfree(mon_dev_name);
2309err_out_mod:
2310	dout("Error adding device %s\n", buf);
2311	module_put(THIS_MODULE);
2312	return rc;
2313}
2314
2315static struct rbd_device *__rbd_get_dev(unsigned long id)
2316{
2317	struct list_head *tmp;
2318	struct rbd_device *rbd_dev;
 
 
 
2319
2320	list_for_each(tmp, &rbd_dev_list) {
2321		rbd_dev = list_entry(tmp, struct rbd_device, node);
2322		if (rbd_dev->id == id)
2323			return rbd_dev;
 
 
 
 
 
 
 
 
 
 
 
2324	}
2325	return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2326}
2327
2328static void rbd_dev_release(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2329{
2330	struct rbd_device *rbd_dev =
2331			container_of(dev, struct rbd_device, dev);
 
 
 
2332
2333	if (rbd_dev->watch_request)
2334		ceph_osdc_unregister_linger_request(&rbd_dev->client->osdc,
2335						    rbd_dev->watch_request);
2336	if (rbd_dev->watch_event)
2337		rbd_req_sync_unwatch(rbd_dev, rbd_dev->obj_md_name);
 
 
 
2338
2339	rbd_put_client(rbd_dev);
 
2340
2341	/* clean up and free blkdev */
2342	rbd_free_disk(rbd_dev);
2343	unregister_blkdev(rbd_dev->major, rbd_dev->name);
2344	kfree(rbd_dev);
 
 
 
 
2345
2346	/* release module ref */
2347	module_put(THIS_MODULE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2348}
2349
2350static ssize_t rbd_remove(struct bus_type *bus,
2351			  const char *buf,
2352			  size_t count)
 
 
2353{
2354	struct rbd_device *rbd_dev = NULL;
2355	int target_id, rc;
2356	unsigned long ul;
2357	int ret = count;
2358
2359	rc = strict_strtoul(buf, 10, &ul);
2360	if (rc)
2361		return rc;
2362
2363	/* convert to int; abort if we lost anything in the conversion */
2364	target_id = (int) ul;
2365	if (target_id != ul)
2366		return -EINVAL;
 
 
 
 
 
2367
2368	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
 
2369
2370	rbd_dev = __rbd_get_dev(target_id);
2371	if (!rbd_dev) {
2372		ret = -ENOENT;
2373		goto done;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2374	}
2375
2376	list_del_init(&rbd_dev->node);
 
 
 
 
2377
2378	__rbd_remove_all_snaps(rbd_dev);
2379	rbd_bus_del_dev(rbd_dev);
2380
2381done:
2382	mutex_unlock(&ctl_mutex);
 
 
2383	return ret;
2384}
2385
2386static ssize_t rbd_snap_add(struct device *dev,
2387			    struct device_attribute *attr,
2388			    const char *buf,
2389			    size_t count)
 
 
2390{
2391	struct rbd_device *rbd_dev = dev_to_rbd(dev);
2392	int ret;
2393	char *name = kmalloc(count + 1, GFP_KERNEL);
2394	if (!name)
2395		return -ENOMEM;
2396
2397	snprintf(name, count, "%s", buf);
 
2398
2399	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
 
 
 
2400
2401	ret = rbd_header_add_snap(rbd_dev,
2402				  name, GFP_KERNEL);
2403	if (ret < 0)
2404		goto err_unlock;
 
2405
2406	ret = __rbd_update_snaps(rbd_dev);
 
 
 
 
 
 
 
 
 
2407	if (ret < 0)
2408		goto err_unlock;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2409
2410	/* shouldn't hold ctl_mutex when notifying.. notify might
2411	   trigger a watch callback that would need to get that mutex */
2412	mutex_unlock(&ctl_mutex);
2413
2414	/* make a best effort, don't error if failed */
2415	rbd_req_sync_notify(rbd_dev, rbd_dev->obj_md_name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2416
2417	ret = count;
2418	kfree(name);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2419	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2420
2421err_unlock:
2422	mutex_unlock(&ctl_mutex);
2423	kfree(name);
2424	return ret;
2425}
2426
2427static ssize_t rbd_snap_rollback(struct device *dev,
2428				 struct device_attribute *attr,
2429				 const char *buf,
2430				 size_t count)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2431{
2432	struct rbd_device *rbd_dev = dev_to_rbd(dev);
2433	int ret;
2434	u64 snapid;
2435	u64 cur_ofs;
2436	char *seg_name = NULL;
2437	char *snap_name = kmalloc(count + 1, GFP_KERNEL);
2438	ret = -ENOMEM;
2439	if (!snap_name)
2440		return ret;
2441
2442	/* parse snaps add command */
2443	snprintf(snap_name, count, "%s", buf);
2444	seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO);
2445	if (!seg_name)
2446		goto done;
 
 
 
 
2447
2448	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 
 
 
 
 
 
 
 
 
 
 
2449
2450	ret = snap_by_name(&rbd_dev->header, snap_name, &snapid, NULL);
2451	if (ret < 0)
2452		goto done_unlock;
2453
2454	dout("snapid=%lld\n", snapid);
 
 
 
 
 
2455
2456	cur_ofs = 0;
2457	while (cur_ofs < rbd_dev->header.image_size) {
2458		cur_ofs += rbd_get_segment(&rbd_dev->header,
2459					   rbd_dev->obj,
2460					   cur_ofs, (u64)-1,
2461					   seg_name, NULL);
2462		dout("seg_name=%s\n", seg_name);
 
 
 
 
 
 
 
 
2463
2464		ret = rbd_req_sync_rollback_obj(rbd_dev, snapid, seg_name);
2465		if (ret < 0)
2466			pr_warning("could not roll back obj %s err=%d\n",
2467				   seg_name, ret);
 
 
 
 
 
2468	}
2469
2470	ret = __rbd_update_snaps(rbd_dev);
2471	if (ret < 0)
2472		goto done_unlock;
 
 
2473
2474	ret = count;
 
 
2475
2476done_unlock:
2477	mutex_unlock(&ctl_mutex);
2478done:
2479	kfree(seg_name);
2480	kfree(snap_name);
2481
 
 
 
 
 
 
 
 
 
 
2482	return ret;
2483}
2484
2485static struct bus_attribute rbd_bus_attrs[] = {
2486	__ATTR(add, S_IWUSR, NULL, rbd_add),
2487	__ATTR(remove, S_IWUSR, NULL, rbd_remove),
2488	__ATTR_NULL
2489};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2490
2491/*
2492 * create control files in sysfs
2493 * /sys/bus/rbd/...
2494 */
2495static int rbd_sysfs_init(void)
2496{
2497	int ret;
2498
2499	rbd_bus_type.bus_attrs = rbd_bus_attrs;
2500
2501	ret = bus_register(&rbd_bus_type);
2502	 if (ret < 0)
2503		return ret;
2504
2505	ret = device_register(&rbd_root_dev);
 
 
2506
2507	return ret;
2508}
2509
2510static void rbd_sysfs_cleanup(void)
2511{
2512	device_unregister(&rbd_root_dev);
2513	bus_unregister(&rbd_bus_type);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2514}
2515
2516int __init rbd_init(void)
2517{
2518	int rc;
2519
2520	rc = rbd_sysfs_init();
 
 
 
 
 
2521	if (rc)
2522		return rc;
2523	spin_lock_init(&node_lock);
2524	pr_info("loaded " DRV_NAME_LONG "\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2525	return 0;
 
 
 
 
 
 
 
 
 
2526}
2527
2528void __exit rbd_exit(void)
2529{
 
2530	rbd_sysfs_cleanup();
 
 
 
 
2531}
2532
2533module_init(rbd_init);
2534module_exit(rbd_exit);
2535
 
2536MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
2537MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
2538MODULE_DESCRIPTION("rados block device");
2539
2540/* following authorship retained from original osdblk.c */
2541MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
2542
 
2543MODULE_LICENSE("GPL");
v5.14.15
   1
   2/*
   3   rbd.c -- Export ceph rados objects as a Linux block device
   4
   5
   6   based on drivers/block/osdblk.c:
   7
   8   Copyright 2009 Red Hat, Inc.
   9
  10   This program is free software; you can redistribute it and/or modify
  11   it under the terms of the GNU General Public License as published by
  12   the Free Software Foundation.
  13
  14   This program is distributed in the hope that it will be useful,
  15   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17   GNU General Public License for more details.
  18
  19   You should have received a copy of the GNU General Public License
  20   along with this program; see the file COPYING.  If not, write to
  21   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  22
  23
  24
  25   For usage instructions, please refer to:
  26
  27                 Documentation/ABI/testing/sysfs-bus-rbd
  28
  29 */
  30
  31#include <linux/ceph/libceph.h>
  32#include <linux/ceph/osd_client.h>
  33#include <linux/ceph/mon_client.h>
  34#include <linux/ceph/cls_lock_client.h>
  35#include <linux/ceph/striper.h>
  36#include <linux/ceph/decode.h>
  37#include <linux/fs_parser.h>
  38#include <linux/bsearch.h>
  39
  40#include <linux/kernel.h>
  41#include <linux/device.h>
  42#include <linux/module.h>
  43#include <linux/blk-mq.h>
  44#include <linux/fs.h>
  45#include <linux/blkdev.h>
  46#include <linux/slab.h>
  47#include <linux/idr.h>
  48#include <linux/workqueue.h>
  49
  50#include "rbd_types.h"
  51
  52#define RBD_DEBUG	/* Activate rbd_assert() calls */
  53
  54/*
  55 * Increment the given counter and return its updated value.
  56 * If the counter is already 0 it will not be incremented.
  57 * If the counter is already at its maximum value returns
  58 * -EINVAL without updating it.
  59 */
  60static int atomic_inc_return_safe(atomic_t *v)
  61{
  62	unsigned int counter;
  63
  64	counter = (unsigned int)atomic_fetch_add_unless(v, 1, 0);
  65	if (counter <= (unsigned int)INT_MAX)
  66		return (int)counter;
  67
  68	atomic_dec(v);
  69
  70	return -EINVAL;
  71}
  72
  73/* Decrement the counter.  Return the resulting value, or -EINVAL */
  74static int atomic_dec_return_safe(atomic_t *v)
  75{
  76	int counter;
  77
  78	counter = atomic_dec_return(v);
  79	if (counter >= 0)
  80		return counter;
  81
  82	atomic_inc(v);
  83
  84	return -EINVAL;
  85}
  86
  87#define RBD_DRV_NAME "rbd"
  88
  89#define RBD_MINORS_PER_MAJOR		256
  90#define RBD_SINGLE_MAJOR_PART_SHIFT	4
  91
  92#define RBD_MAX_PARENT_CHAIN_LEN	16
  93
  94#define RBD_SNAP_DEV_NAME_PREFIX	"snap_"
  95#define RBD_MAX_SNAP_NAME_LEN	\
  96			(NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
  97
  98#define RBD_MAX_SNAP_COUNT	510	/* allows max snapc to fit in 4KB */
 
 
 
  99
 100#define RBD_SNAP_HEAD_NAME	"-"
 101
 102#define	BAD_SNAP_INDEX	U32_MAX		/* invalid index into snap array */
 103
 104/* This allows a single page to hold an image name sent by OSD */
 105#define RBD_IMAGE_NAME_LEN_MAX	(PAGE_SIZE - sizeof (__le32) - 1)
 106#define RBD_IMAGE_ID_LEN_MAX	64
 107
 108#define RBD_OBJ_PREFIX_LEN_MAX	64
 109
 110#define RBD_NOTIFY_TIMEOUT	5	/* seconds */
 111#define RBD_RETRY_DELAY		msecs_to_jiffies(1000)
 112
 113/* Feature bits */
 114
 115#define RBD_FEATURE_LAYERING		(1ULL<<0)
 116#define RBD_FEATURE_STRIPINGV2		(1ULL<<1)
 117#define RBD_FEATURE_EXCLUSIVE_LOCK	(1ULL<<2)
 118#define RBD_FEATURE_OBJECT_MAP		(1ULL<<3)
 119#define RBD_FEATURE_FAST_DIFF		(1ULL<<4)
 120#define RBD_FEATURE_DEEP_FLATTEN	(1ULL<<5)
 121#define RBD_FEATURE_DATA_POOL		(1ULL<<7)
 122#define RBD_FEATURE_OPERATIONS		(1ULL<<8)
 123
 124#define RBD_FEATURES_ALL	(RBD_FEATURE_LAYERING |		\
 125				 RBD_FEATURE_STRIPINGV2 |	\
 126				 RBD_FEATURE_EXCLUSIVE_LOCK |	\
 127				 RBD_FEATURE_OBJECT_MAP |	\
 128				 RBD_FEATURE_FAST_DIFF |	\
 129				 RBD_FEATURE_DEEP_FLATTEN |	\
 130				 RBD_FEATURE_DATA_POOL |	\
 131				 RBD_FEATURE_OPERATIONS)
 132
 133/* Features supported by this (client software) implementation. */
 134
 135#define RBD_FEATURES_SUPPORTED	(RBD_FEATURES_ALL)
 136
 137/*
 138 * An RBD device name will be "rbd#", where the "rbd" comes from
 139 * RBD_DRV_NAME above, and # is a unique integer identifier.
 140 */
 141#define DEV_NAME_LEN		32
 142
 143/*
 144 * block device image metadata (in-memory version)
 145 */
 146struct rbd_image_header {
 147	/* These six fields never change for a given rbd image */
 148	char *object_prefix;
 149	__u8 obj_order;
 150	u64 stripe_unit;
 151	u64 stripe_count;
 152	s64 data_pool_id;
 153	u64 features;		/* Might be changeable someday? */
 154
 155	/* The remaining fields need to be updated occasionally */
 156	u64 image_size;
 157	struct ceph_snap_context *snapc;
 158	char *snap_names;	/* format 1 only */
 159	u64 *snap_sizes;	/* format 1 only */
 160};
 161
 162/*
 163 * An rbd image specification.
 164 *
 165 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
 166 * identify an image.  Each rbd_dev structure includes a pointer to
 167 * an rbd_spec structure that encapsulates this identity.
 168 *
 169 * Each of the id's in an rbd_spec has an associated name.  For a
 170 * user-mapped image, the names are supplied and the id's associated
 171 * with them are looked up.  For a layered image, a parent image is
 172 * defined by the tuple, and the names are looked up.
 173 *
 174 * An rbd_dev structure contains a parent_spec pointer which is
 175 * non-null if the image it represents is a child in a layered
 176 * image.  This pointer will refer to the rbd_spec structure used
 177 * by the parent rbd_dev for its own identity (i.e., the structure
 178 * is shared between the parent and child).
 179 *
 180 * Since these structures are populated once, during the discovery
 181 * phase of image construction, they are effectively immutable so
 182 * we make no effort to synchronize access to them.
 183 *
 184 * Note that code herein does not assume the image name is known (it
 185 * could be a null pointer).
 186 */
 187struct rbd_spec {
 188	u64		pool_id;
 189	const char	*pool_name;
 190	const char	*pool_ns;	/* NULL if default, never "" */
 191
 192	const char	*image_id;
 193	const char	*image_name;
 194
 195	u64		snap_id;
 196	const char	*snap_name;
 197
 198	struct kref	kref;
 199};
 200
 201/*
 202 * an instance of the client.  multiple devices may share an rbd client.
 203 */
 204struct rbd_client {
 205	struct ceph_client	*client;
 
 206	struct kref		kref;
 207	struct list_head	node;
 208};
 209
 210struct pending_result {
 211	int			result;		/* first nonzero result */
 212	int			num_pending;
 213};
 214
 215struct rbd_img_request;
 216
 217enum obj_request_type {
 218	OBJ_REQUEST_NODATA = 1,
 219	OBJ_REQUEST_BIO,	/* pointer into provided bio (list) */
 220	OBJ_REQUEST_BVECS,	/* pointer into provided bio_vec array */
 221	OBJ_REQUEST_OWN_BVECS,	/* private bio_vec array, doesn't own pages */
 
 
 
 222};
 223
 224enum obj_operation_type {
 225	OBJ_OP_READ = 1,
 226	OBJ_OP_WRITE,
 227	OBJ_OP_DISCARD,
 228	OBJ_OP_ZEROOUT,
 229};
 230
 231#define RBD_OBJ_FLAG_DELETION			(1U << 0)
 232#define RBD_OBJ_FLAG_COPYUP_ENABLED		(1U << 1)
 233#define RBD_OBJ_FLAG_COPYUP_ZEROS		(1U << 2)
 234#define RBD_OBJ_FLAG_MAY_EXIST			(1U << 3)
 235#define RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT	(1U << 4)
 236
 237enum rbd_obj_read_state {
 238	RBD_OBJ_READ_START = 1,
 239	RBD_OBJ_READ_OBJECT,
 240	RBD_OBJ_READ_PARENT,
 241};
 242
 243/*
 244 * Writes go through the following state machine to deal with
 245 * layering:
 246 *
 247 *            . . . . . RBD_OBJ_WRITE_GUARD. . . . . . . . . . . . . .
 248 *            .                 |                                    .
 249 *            .                 v                                    .
 250 *            .    RBD_OBJ_WRITE_READ_FROM_PARENT. . .               .
 251 *            .                 |                    .               .
 252 *            .                 v                    v (deep-copyup  .
 253 *    (image  .   RBD_OBJ_WRITE_COPYUP_EMPTY_SNAPC   .  not needed)  .
 254 * flattened) v                 |                    .               .
 255 *            .                 v                    .               .
 256 *            . . . .RBD_OBJ_WRITE_COPYUP_OPS. . . . .      (copyup  .
 257 *                              |                        not needed) v
 258 *                              v                                    .
 259 *                            done . . . . . . . . . . . . . . . . . .
 260 *                              ^
 261 *                              |
 262 *                     RBD_OBJ_WRITE_FLAT
 263 *
 264 * Writes start in RBD_OBJ_WRITE_GUARD or _FLAT, depending on whether
 265 * assert_exists guard is needed or not (in some cases it's not needed
 266 * even if there is a parent).
 267 */
 268enum rbd_obj_write_state {
 269	RBD_OBJ_WRITE_START = 1,
 270	RBD_OBJ_WRITE_PRE_OBJECT_MAP,
 271	RBD_OBJ_WRITE_OBJECT,
 272	__RBD_OBJ_WRITE_COPYUP,
 273	RBD_OBJ_WRITE_COPYUP,
 274	RBD_OBJ_WRITE_POST_OBJECT_MAP,
 275};
 276
 277enum rbd_obj_copyup_state {
 278	RBD_OBJ_COPYUP_START = 1,
 279	RBD_OBJ_COPYUP_READ_PARENT,
 280	__RBD_OBJ_COPYUP_OBJECT_MAPS,
 281	RBD_OBJ_COPYUP_OBJECT_MAPS,
 282	__RBD_OBJ_COPYUP_WRITE_OBJECT,
 283	RBD_OBJ_COPYUP_WRITE_OBJECT,
 284};
 285
 286struct rbd_obj_request {
 287	struct ceph_object_extent ex;
 288	unsigned int		flags;	/* RBD_OBJ_FLAG_* */
 289	union {
 290		enum rbd_obj_read_state	 read_state;	/* for reads */
 291		enum rbd_obj_write_state write_state;	/* for writes */
 292	};
 293
 294	struct rbd_img_request	*img_request;
 295	struct ceph_file_extent	*img_extents;
 296	u32			num_img_extents;
 297
 298	union {
 299		struct ceph_bio_iter	bio_pos;
 300		struct {
 301			struct ceph_bvec_iter	bvec_pos;
 302			u32			bvec_count;
 303			u32			bvec_idx;
 304		};
 305	};
 306
 307	enum rbd_obj_copyup_state copyup_state;
 308	struct bio_vec		*copyup_bvecs;
 309	u32			copyup_bvec_count;
 310
 311	struct list_head	osd_reqs;	/* w/ r_private_item */
 312
 313	struct mutex		state_mutex;
 314	struct pending_result	pending;
 315	struct kref		kref;
 
 316};
 317
 318enum img_req_flags {
 319	IMG_REQ_CHILD,		/* initiator: block = 0, child image = 1 */
 320	IMG_REQ_LAYERED,	/* ENOENT handling: normal = 0, layered = 1 */
 321};
 322
 323enum rbd_img_state {
 324	RBD_IMG_START = 1,
 325	RBD_IMG_EXCLUSIVE_LOCK,
 326	__RBD_IMG_OBJECT_REQUESTS,
 327	RBD_IMG_OBJECT_REQUESTS,
 328};
 329
 330struct rbd_img_request {
 331	struct rbd_device	*rbd_dev;
 332	enum obj_operation_type	op_type;
 333	enum obj_request_type	data_type;
 334	unsigned long		flags;
 335	enum rbd_img_state	state;
 336	union {
 337		u64			snap_id;	/* for reads */
 338		struct ceph_snap_context *snapc;	/* for writes */
 339	};
 340	struct rbd_obj_request	*obj_request;	/* obj req initiator */
 341
 342	struct list_head	lock_item;
 343	struct list_head	object_extents;	/* obj_req.ex structs */
 344
 345	struct mutex		state_mutex;
 346	struct pending_result	pending;
 347	struct work_struct	work;
 348	int			work_result;
 349};
 350
 351#define for_each_obj_request(ireq, oreq) \
 352	list_for_each_entry(oreq, &(ireq)->object_extents, ex.oe_item)
 353#define for_each_obj_request_safe(ireq, oreq, n) \
 354	list_for_each_entry_safe(oreq, n, &(ireq)->object_extents, ex.oe_item)
 355
 356enum rbd_watch_state {
 357	RBD_WATCH_STATE_UNREGISTERED,
 358	RBD_WATCH_STATE_REGISTERED,
 359	RBD_WATCH_STATE_ERROR,
 360};
 361
 362enum rbd_lock_state {
 363	RBD_LOCK_STATE_UNLOCKED,
 364	RBD_LOCK_STATE_LOCKED,
 365	RBD_LOCK_STATE_RELEASING,
 366};
 367
 368/* WatchNotify::ClientId */
 369struct rbd_client_id {
 370	u64 gid;
 371	u64 handle;
 372};
 373
 374struct rbd_mapping {
 375	u64                     size;
 376};
 377
 378/*
 379 * a single device
 380 */
 381struct rbd_device {
 382	int			dev_id;		/* blkdev unique id */
 383
 384	int			major;		/* blkdev assigned major */
 385	int			minor;
 386	struct gendisk		*disk;		/* blkdev's gendisk and rq */
 
 387
 388	u32			image_format;	/* Either 1 or 2 */
 389	struct rbd_client	*rbd_client;
 390
 391	char			name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
 392
 393	spinlock_t		lock;		/* queue, flags, open_count */
 394
 395	struct rbd_image_header	header;
 396	unsigned long		flags;		/* possibly lock protected */
 397	struct rbd_spec		*spec;
 398	struct rbd_options	*opts;
 399	char			*config_info;	/* add{,_single_major} string */
 400
 401	struct ceph_object_id	header_oid;
 402	struct ceph_object_locator header_oloc;
 403
 404	struct ceph_file_layout	layout;		/* used for all rbd requests */
 405
 406	struct mutex		watch_mutex;
 407	enum rbd_watch_state	watch_state;
 408	struct ceph_osd_linger_request *watch_handle;
 409	u64			watch_cookie;
 410	struct delayed_work	watch_dwork;
 411
 412	struct rw_semaphore	lock_rwsem;
 413	enum rbd_lock_state	lock_state;
 414	char			lock_cookie[32];
 415	struct rbd_client_id	owner_cid;
 416	struct work_struct	acquired_lock_work;
 417	struct work_struct	released_lock_work;
 418	struct delayed_work	lock_dwork;
 419	struct work_struct	unlock_work;
 420	spinlock_t		lock_lists_lock;
 421	struct list_head	acquiring_list;
 422	struct list_head	running_list;
 423	struct completion	acquire_wait;
 424	int			acquire_err;
 425	struct completion	releasing_wait;
 426
 427	spinlock_t		object_map_lock;
 428	u8			*object_map;
 429	u64			object_map_size;	/* in objects */
 430	u64			object_map_flags;
 431
 432	struct workqueue_struct	*task_wq;
 433
 434	struct rbd_spec		*parent_spec;
 435	u64			parent_overlap;
 436	atomic_t		parent_ref;
 437	struct rbd_device	*parent;
 438
 439	/* Block layer tags. */
 440	struct blk_mq_tag_set	tag_set;
 441
 442	/* protects updating the header */
 443	struct rw_semaphore     header_rwsem;
 444
 445	struct rbd_mapping	mapping;
 446
 447	struct list_head	node;
 448
 449	/* sysfs related */
 450	struct device		dev;
 451	unsigned long		open_count;	/* protected by lock */
 452};
 453
 454/*
 455 * Flag bits for rbd_dev->flags:
 456 * - REMOVING (which is coupled with rbd_dev->open_count) is protected
 457 *   by rbd_dev->lock
 458 */
 459enum rbd_dev_flags {
 460	RBD_DEV_FLAG_EXISTS,	/* rbd_dev_device_setup() ran */
 461	RBD_DEV_FLAG_REMOVING,	/* this mapping is being removed */
 462	RBD_DEV_FLAG_READONLY,  /* -o ro or snapshot */
 463};
 464
 465static DEFINE_MUTEX(client_mutex);	/* Serialize client creation */
 466
 
 467static LIST_HEAD(rbd_dev_list);    /* devices */
 468static DEFINE_SPINLOCK(rbd_dev_list_lock);
 469
 470static LIST_HEAD(rbd_client_list);		/* clients */
 471static DEFINE_SPINLOCK(rbd_client_list_lock);
 472
 473/* Slab caches for frequently-allocated structures */
 474
 475static struct kmem_cache	*rbd_img_request_cache;
 476static struct kmem_cache	*rbd_obj_request_cache;
 477
 478static int rbd_major;
 479static DEFINE_IDA(rbd_dev_id_ida);
 480
 481static struct workqueue_struct *rbd_wq;
 482
 483static struct ceph_snap_context rbd_empty_snapc = {
 484	.nref = REFCOUNT_INIT(1),
 485};
 486
 487/*
 488 * single-major requires >= 0.75 version of userspace rbd utility.
 489 */
 490static bool single_major = true;
 491module_param(single_major, bool, 0444);
 492MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)");
 493
 494static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count);
 495static ssize_t remove_store(struct bus_type *bus, const char *buf,
 496			    size_t count);
 497static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
 498				      size_t count);
 499static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
 500					 size_t count);
 501static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth);
 502
 503static int rbd_dev_id_to_minor(int dev_id)
 504{
 505	return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
 506}
 507
 508static int minor_to_rbd_dev_id(int minor)
 509{
 510	return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
 511}
 512
 513static bool rbd_is_ro(struct rbd_device *rbd_dev)
 514{
 515	return test_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags);
 516}
 517
 518static bool rbd_is_snap(struct rbd_device *rbd_dev)
 519{
 520	return rbd_dev->spec->snap_id != CEPH_NOSNAP;
 521}
 522
 523static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev)
 524{
 525	lockdep_assert_held(&rbd_dev->lock_rwsem);
 526
 527	return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED ||
 528	       rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING;
 529}
 530
 531static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
 532{
 533	bool is_lock_owner;
 
 534
 535	down_read(&rbd_dev->lock_rwsem);
 536	is_lock_owner = __rbd_is_lock_owner(rbd_dev);
 537	up_read(&rbd_dev->lock_rwsem);
 538	return is_lock_owner;
 539}
 540
 541static ssize_t supported_features_show(struct bus_type *bus, char *buf)
 542{
 543	return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
 544}
 545
 546static BUS_ATTR_WO(add);
 547static BUS_ATTR_WO(remove);
 548static BUS_ATTR_WO(add_single_major);
 549static BUS_ATTR_WO(remove_single_major);
 550static BUS_ATTR_RO(supported_features);
 551
 552static struct attribute *rbd_bus_attrs[] = {
 553	&bus_attr_add.attr,
 554	&bus_attr_remove.attr,
 555	&bus_attr_add_single_major.attr,
 556	&bus_attr_remove_single_major.attr,
 557	&bus_attr_supported_features.attr,
 558	NULL,
 559};
 560
 561static umode_t rbd_bus_is_visible(struct kobject *kobj,
 562				  struct attribute *attr, int index)
 563{
 564	if (!single_major &&
 565	    (attr == &bus_attr_add_single_major.attr ||
 566	     attr == &bus_attr_remove_single_major.attr))
 567		return 0;
 568
 569	return attr->mode;
 570}
 571
 572static const struct attribute_group rbd_bus_group = {
 573	.attrs = rbd_bus_attrs,
 574	.is_visible = rbd_bus_is_visible,
 575};
 576__ATTRIBUTE_GROUPS(rbd_bus);
 577
 578static struct bus_type rbd_bus_type = {
 579	.name		= "rbd",
 580	.bus_groups	= rbd_bus_groups,
 581};
 582
 583static void rbd_root_dev_release(struct device *dev)
 584{
 585}
 586
 587static struct device rbd_root_dev = {
 588	.init_name =    "rbd",
 589	.release =      rbd_root_dev_release,
 590};
 591
 592static __printf(2, 3)
 593void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
 594{
 595	struct va_format vaf;
 596	va_list args;
 597
 598	va_start(args, fmt);
 599	vaf.fmt = fmt;
 600	vaf.va = &args;
 601
 602	if (!rbd_dev)
 603		printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
 604	else if (rbd_dev->disk)
 605		printk(KERN_WARNING "%s: %s: %pV\n",
 606			RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
 607	else if (rbd_dev->spec && rbd_dev->spec->image_name)
 608		printk(KERN_WARNING "%s: image %s: %pV\n",
 609			RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
 610	else if (rbd_dev->spec && rbd_dev->spec->image_id)
 611		printk(KERN_WARNING "%s: id %s: %pV\n",
 612			RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
 613	else	/* punt */
 614		printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
 615			RBD_DRV_NAME, rbd_dev, &vaf);
 616	va_end(args);
 617}
 618
 619#ifdef RBD_DEBUG
 620#define rbd_assert(expr)						\
 621		if (unlikely(!(expr))) {				\
 622			printk(KERN_ERR "\nAssertion failure in %s() "	\
 623						"at line %d:\n\n"	\
 624					"\trbd_assert(%s);\n\n",	\
 625					__func__, __LINE__, #expr);	\
 626			BUG();						\
 627		}
 628#else /* !RBD_DEBUG */
 629#  define rbd_assert(expr)	((void) 0)
 630#endif /* !RBD_DEBUG */
 631
 632static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
 633
 634static int rbd_dev_refresh(struct rbd_device *rbd_dev);
 635static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
 636static int rbd_dev_header_info(struct rbd_device *rbd_dev);
 637static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev);
 638static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
 639					u64 snap_id);
 640static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
 641				u8 *order, u64 *snap_size);
 642static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev);
 643
 644static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result);
 645static void rbd_img_handle_request(struct rbd_img_request *img_req, int result);
 646
 647/*
 648 * Return true if nothing else is pending.
 649 */
 650static bool pending_result_dec(struct pending_result *pending, int *result)
 651{
 652	rbd_assert(pending->num_pending > 0);
 653
 654	if (*result && !pending->result)
 655		pending->result = *result;
 656	if (--pending->num_pending)
 657		return false;
 658
 659	*result = pending->result;
 660	return true;
 661}
 662
 663static int rbd_open(struct block_device *bdev, fmode_t mode)
 664{
 665	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
 666	bool removing = false;
 667
 668	spin_lock_irq(&rbd_dev->lock);
 669	if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
 670		removing = true;
 671	else
 672		rbd_dev->open_count++;
 673	spin_unlock_irq(&rbd_dev->lock);
 674	if (removing)
 675		return -ENOENT;
 676
 677	(void) get_device(&rbd_dev->dev);
 678
 679	return 0;
 680}
 681
 682static void rbd_release(struct gendisk *disk, fmode_t mode)
 683{
 684	struct rbd_device *rbd_dev = disk->private_data;
 685	unsigned long open_count_before;
 686
 687	spin_lock_irq(&rbd_dev->lock);
 688	open_count_before = rbd_dev->open_count--;
 689	spin_unlock_irq(&rbd_dev->lock);
 690	rbd_assert(open_count_before > 0);
 691
 692	put_device(&rbd_dev->dev);
 693}
 694
 695static const struct block_device_operations rbd_bd_ops = {
 696	.owner			= THIS_MODULE,
 697	.open			= rbd_open,
 698	.release		= rbd_release,
 699};
 700
 701/*
 702 * Initialize an rbd client instance.  Success or not, this function
 703 * consumes ceph_opts.  Caller holds client_mutex.
 704 */
 705static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
 
 706{
 707	struct rbd_client *rbdc;
 708	int ret = -ENOMEM;
 709
 710	dout("%s:\n", __func__);
 711	rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
 712	if (!rbdc)
 713		goto out_opt;
 714
 715	kref_init(&rbdc->kref);
 716	INIT_LIST_HEAD(&rbdc->node);
 717
 718	rbdc->client = ceph_create_client(ceph_opts, rbdc);
 719	if (IS_ERR(rbdc->client))
 720		goto out_rbdc;
 721	ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
 722
 723	ret = ceph_open_session(rbdc->client);
 724	if (ret < 0)
 725		goto out_client;
 726
 727	spin_lock(&rbd_client_list_lock);
 
 
 728	list_add_tail(&rbdc->node, &rbd_client_list);
 729	spin_unlock(&rbd_client_list_lock);
 730
 731	dout("%s: rbdc %p\n", __func__, rbdc);
 
 732
 733	return rbdc;
 734out_client:
 735	ceph_destroy_client(rbdc->client);
 736out_rbdc:
 737	kfree(rbdc);
 738out_opt:
 739	if (ceph_opts)
 740		ceph_destroy_options(ceph_opts);
 741	dout("%s: error %d\n", __func__, ret);
 742
 743	return ERR_PTR(ret);
 744}
 745
 746static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
 747{
 748	kref_get(&rbdc->kref);
 749
 750	return rbdc;
 751}
 752
 753/*
 754 * Find a ceph client with specific addr and configuration.  If
 755 * found, bump its reference count.
 756 */
 757static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
 758{
 759	struct rbd_client *client_node;
 760	bool found = false;
 761
 762	if (ceph_opts->flags & CEPH_OPT_NOSHARE)
 763		return NULL;
 764
 765	spin_lock(&rbd_client_list_lock);
 766	list_for_each_entry(client_node, &rbd_client_list, node) {
 767		if (!ceph_compare_options(ceph_opts, client_node->client)) {
 768			__rbd_get_client(client_node);
 769
 770			found = true;
 771			break;
 772		}
 773	}
 774	spin_unlock(&rbd_client_list_lock);
 775
 776	return found ? client_node : NULL;
 777}
 778
 779/*
 780 * (Per device) rbd map options
 781 */
 782enum {
 783	Opt_queue_depth,
 784	Opt_alloc_size,
 785	Opt_lock_timeout,
 786	/* int args above */
 787	Opt_pool_ns,
 788	Opt_compression_hint,
 789	/* string args above */
 790	Opt_read_only,
 791	Opt_read_write,
 792	Opt_lock_on_read,
 793	Opt_exclusive,
 794	Opt_notrim,
 795};
 796
 797enum {
 798	Opt_compression_hint_none,
 799	Opt_compression_hint_compressible,
 800	Opt_compression_hint_incompressible,
 
 801};
 802
 803static const struct constant_table rbd_param_compression_hint[] = {
 804	{"none",		Opt_compression_hint_none},
 805	{"compressible",	Opt_compression_hint_compressible},
 806	{"incompressible",	Opt_compression_hint_incompressible},
 807	{}
 808};
 809
 810static const struct fs_parameter_spec rbd_parameters[] = {
 811	fsparam_u32	("alloc_size",			Opt_alloc_size),
 812	fsparam_enum	("compression_hint",		Opt_compression_hint,
 813			 rbd_param_compression_hint),
 814	fsparam_flag	("exclusive",			Opt_exclusive),
 815	fsparam_flag	("lock_on_read",		Opt_lock_on_read),
 816	fsparam_u32	("lock_timeout",		Opt_lock_timeout),
 817	fsparam_flag	("notrim",			Opt_notrim),
 818	fsparam_string	("_pool_ns",			Opt_pool_ns),
 819	fsparam_u32	("queue_depth",			Opt_queue_depth),
 820	fsparam_flag	("read_only",			Opt_read_only),
 821	fsparam_flag	("read_write",			Opt_read_write),
 822	fsparam_flag	("ro",				Opt_read_only),
 823	fsparam_flag	("rw",				Opt_read_write),
 824	{}
 825};
 826
 827struct rbd_options {
 828	int	queue_depth;
 829	int	alloc_size;
 830	unsigned long	lock_timeout;
 831	bool	read_only;
 832	bool	lock_on_read;
 833	bool	exclusive;
 834	bool	trim;
 
 
 
 
 
 
 835
 836	u32 alloc_hint_flags;  /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */
 837};
 838
 839#define RBD_QUEUE_DEPTH_DEFAULT	BLKDEV_MAX_RQ
 840#define RBD_ALLOC_SIZE_DEFAULT	(64 * 1024)
 841#define RBD_LOCK_TIMEOUT_DEFAULT 0  /* no timeout */
 842#define RBD_READ_ONLY_DEFAULT	false
 843#define RBD_LOCK_ON_READ_DEFAULT false
 844#define RBD_EXCLUSIVE_DEFAULT	false
 845#define RBD_TRIM_DEFAULT	true
 846
 847struct rbd_parse_opts_ctx {
 848	struct rbd_spec		*spec;
 849	struct ceph_options	*copts;
 850	struct rbd_options	*opts;
 851};
 852
 853static char* obj_op_name(enum obj_operation_type op_type)
 854{
 855	switch (op_type) {
 856	case OBJ_OP_READ:
 857		return "read";
 858	case OBJ_OP_WRITE:
 859		return "write";
 860	case OBJ_OP_DISCARD:
 861		return "discard";
 862	case OBJ_OP_ZEROOUT:
 863		return "zeroout";
 864	default:
 865		return "???";
 866	}
 
 867}
 868
 869/*
 870 * Destroy ceph client
 871 *
 872 * Caller must hold rbd_client_list_lock.
 873 */
 874static void rbd_client_release(struct kref *kref)
 
 875{
 876	struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
 
 
 
 877
 878	dout("%s: rbdc %p\n", __func__, rbdc);
 879	spin_lock(&rbd_client_list_lock);
 880	list_del(&rbdc->node);
 881	spin_unlock(&rbd_client_list_lock);
 882
 883	ceph_destroy_client(rbdc->client);
 884	kfree(rbdc);
 885}
 886
 887/*
 888 * Drop reference to ceph client node. If it's not referenced anymore, release
 889 * it.
 890 */
 891static void rbd_put_client(struct rbd_client *rbdc)
 892{
 893	if (rbdc)
 894		kref_put(&rbdc->kref, rbd_client_release);
 895}
 896
 897/*
 898 * Get a ceph client with specific addr and configuration, if one does
 899 * not exist create it.  Either way, ceph_opts is consumed by this
 900 * function.
 901 */
 902static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
 903{
 904	struct rbd_client *rbdc;
 905	int ret;
 906
 907	mutex_lock(&client_mutex);
 908	rbdc = rbd_client_find(ceph_opts);
 909	if (rbdc) {
 910		ceph_destroy_options(ceph_opts);
 911
 912		/*
 913		 * Using an existing client.  Make sure ->pg_pools is up to
 914		 * date before we look up the pool id in do_rbd_add().
 915		 */
 916		ret = ceph_wait_for_latest_osdmap(rbdc->client,
 917					rbdc->client->options->mount_timeout);
 918		if (ret) {
 919			rbd_warn(NULL, "failed to get latest osdmap: %d", ret);
 920			rbd_put_client(rbdc);
 921			rbdc = ERR_PTR(ret);
 922		}
 923	} else {
 924		rbdc = rbd_client_create(ceph_opts);
 925	}
 926	mutex_unlock(&client_mutex);
 927
 928	return rbdc;
 929}
 
 
 
 930
 931static bool rbd_image_format_valid(u32 image_format)
 932{
 933	return image_format == 1 || image_format == 2;
 
 
 
 934}
 935
 936static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
 
 
 
 937{
 938	size_t size;
 939	u32 snap_count;
 940
 941	/* The header has to start with the magic rbd header text */
 942	if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
 943		return false;
 
 944
 945	/* The bio layer requires at least sector-sized I/O */
 946
 947	if (ondisk->options.order < SECTOR_SHIFT)
 948		return false;
 949
 950	/* If we use u64 in a few spots we may be able to loosen this */
 951
 952	if (ondisk->options.order > 8 * sizeof (int) - 1)
 953		return false;
 954
 955	/*
 956	 * The size of a snapshot header has to fit in a size_t, and
 957	 * that limits the number of snapshots.
 958	 */
 959	snap_count = le32_to_cpu(ondisk->snap_count);
 960	size = SIZE_MAX - sizeof (struct ceph_snap_context);
 961	if (snap_count > size / sizeof (__le64))
 962		return false;
 963
 964	/*
 965	 * Not only that, but the size of the entire the snapshot
 966	 * header must also be representable in a size_t.
 967	 */
 968	size -= snap_count * sizeof (__le64);
 969	if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
 970		return false;
 971
 972	return true;
 973}
 974
 975/*
 976 * returns the size of an object in the image
 
 977 */
 978static u32 rbd_obj_bytes(struct rbd_image_header *header)
 979{
 980	return 1U << header->obj_order;
 
 
 981}
 982
 983static void rbd_init_layout(struct rbd_device *rbd_dev)
 
 
 
 984{
 985	if (rbd_dev->header.stripe_unit == 0 ||
 986	    rbd_dev->header.stripe_count == 0) {
 987		rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header);
 988		rbd_dev->header.stripe_count = 1;
 989	}
 990
 991	rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit;
 992	rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count;
 993	rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header);
 994	rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ?
 995			  rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id;
 996	RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
 997}
 998
 999/*
1000 * Fill an rbd image header with information from the given format 1
1001 * on-disk header.
1002 */
1003static int rbd_header_from_disk(struct rbd_device *rbd_dev,
1004				 struct rbd_image_header_ondisk *ondisk)
 
 
1005{
1006	struct rbd_image_header *header = &rbd_dev->header;
1007	bool first_time = header->object_prefix == NULL;
1008	struct ceph_snap_context *snapc;
1009	char *object_prefix = NULL;
1010	char *snap_names = NULL;
1011	u64 *snap_sizes = NULL;
1012	u32 snap_count;
1013	int ret = -ENOMEM;
1014	u32 i;
1015
1016	/* Allocate this now to avoid having to handle failure below */
1017
1018	if (first_time) {
1019		object_prefix = kstrndup(ondisk->object_prefix,
1020					 sizeof(ondisk->object_prefix),
1021					 GFP_KERNEL);
1022		if (!object_prefix)
1023			return -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
1024	}
 
 
1025
1026	/* Allocate the snapshot context and fill it in */
 
 
 
 
 
 
 
 
1027
1028	snap_count = le32_to_cpu(ondisk->snap_count);
1029	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
1030	if (!snapc)
1031		goto out_err;
1032	snapc->seq = le64_to_cpu(ondisk->snap_seq);
1033	if (snap_count) {
1034		struct rbd_image_snap_ondisk *snaps;
1035		u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
1036
1037		/* We'll keep a copy of the snapshot names... */
1038
1039		if (snap_names_len > (u64)SIZE_MAX)
1040			goto out_2big;
1041		snap_names = kmalloc(snap_names_len, GFP_KERNEL);
1042		if (!snap_names)
1043			goto out_err;
1044
1045		/* ...as well as the array of their sizes. */
1046		snap_sizes = kmalloc_array(snap_count,
1047					   sizeof(*header->snap_sizes),
1048					   GFP_KERNEL);
1049		if (!snap_sizes)
1050			goto out_err;
1051
1052		/*
1053		 * Copy the names, and fill in each snapshot's id
1054		 * and size.
1055		 *
1056		 * Note that rbd_dev_v1_header_info() guarantees the
1057		 * ondisk buffer we're working with has
1058		 * snap_names_len bytes beyond the end of the
1059		 * snapshot id array, this memcpy() is safe.
1060		 */
1061		memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
1062		snaps = ondisk->snaps;
1063		for (i = 0; i < snap_count; i++) {
1064			snapc->snaps[i] = le64_to_cpu(snaps[i].id);
1065			snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
 
 
1066		}
1067	}
1068
1069	/* We won't fail any more, fill in the header */
1070
1071	if (first_time) {
1072		header->object_prefix = object_prefix;
1073		header->obj_order = ondisk->options.order;
1074		rbd_init_layout(rbd_dev);
1075	} else {
1076		ceph_put_snap_context(header->snapc);
1077		kfree(header->snap_names);
1078		kfree(header->snap_sizes);
1079	}
1080
1081	/* The remaining fields always get updated (when we refresh) */
1082
1083	header->image_size = le64_to_cpu(ondisk->image_size);
1084	header->snapc = snapc;
1085	header->snap_names = snap_names;
1086	header->snap_sizes = snap_sizes;
1087
1088	return 0;
1089out_2big:
1090	ret = -EIO;
1091out_err:
1092	kfree(snap_sizes);
1093	kfree(snap_names);
1094	ceph_put_snap_context(snapc);
1095	kfree(object_prefix);
1096
 
 
 
 
1097	return ret;
1098}
1099
1100static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
1101{
1102	const char *snap_name;
1103
1104	rbd_assert(which < rbd_dev->header.snapc->num_snaps);
1105
1106	/* Skip over names until we find the one we are looking for */
1107
1108	snap_name = rbd_dev->header.snap_names;
1109	while (which--)
1110		snap_name += strlen(snap_name) + 1;
1111
1112	return kstrdup(snap_name, GFP_KERNEL);
1113}
1114
1115/*
1116 * Snapshot id comparison function for use with qsort()/bsearch().
1117 * Note that result is for snapshots in *descending* order.
1118 */
1119static int snapid_compare_reverse(const void *s1, const void *s2)
1120{
1121	u64 snap_id1 = *(u64 *)s1;
1122	u64 snap_id2 = *(u64 *)s2;
1123
1124	if (snap_id1 < snap_id2)
1125		return 1;
1126	return snap_id1 == snap_id2 ? 0 : -1;
1127}
1128
1129/*
1130 * Search a snapshot context to see if the given snapshot id is
1131 * present.
1132 *
1133 * Returns the position of the snapshot id in the array if it's found,
1134 * or BAD_SNAP_INDEX otherwise.
1135 *
1136 * Note: The snapshot array is in kept sorted (by the osd) in
1137 * reverse order, highest snapshot id first.
1138 */
1139static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
1140{
1141	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1142	u64 *found;
1143
1144	found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
1145				sizeof (snap_id), snapid_compare_reverse);
1146
1147	return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1148}
1149
1150static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
1151					u64 snap_id)
1152{
1153	u32 which;
1154	const char *snap_name;
1155
1156	which = rbd_dev_snap_index(rbd_dev, snap_id);
1157	if (which == BAD_SNAP_INDEX)
1158		return ERR_PTR(-ENOENT);
 
 
 
 
 
1159
1160	snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
1161	return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1162}
1163
1164static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
1165{
1166	if (snap_id == CEPH_NOSNAP)
1167		return RBD_SNAP_HEAD_NAME;
1168
1169	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1170	if (rbd_dev->image_format == 1)
1171		return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1172
1173	return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1174}
1175
1176static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
1177				u64 *snap_size)
 
1178{
1179	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1180	if (snap_id == CEPH_NOSNAP) {
1181		*snap_size = rbd_dev->header.image_size;
1182	} else if (rbd_dev->image_format == 1) {
1183		u32 which;
1184
1185		which = rbd_dev_snap_index(rbd_dev, snap_id);
1186		if (which == BAD_SNAP_INDEX)
1187			return -ENOENT;
1188
1189		*snap_size = rbd_dev->header.snap_sizes[which];
 
 
 
 
 
 
 
 
 
 
 
1190	} else {
1191		u64 size = 0;
1192		int ret;
1193
1194		ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
1195		if (ret)
1196			return ret;
1197
1198		*snap_size = size;
 
1199	}
1200	return 0;
1201}
1202
1203static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1204{
1205	u64 snap_id = rbd_dev->spec->snap_id;
1206	u64 size = 0;
1207	int ret;
1208
1209	ret = rbd_snap_size(rbd_dev, snap_id, &size);
1210	if (ret)
1211		return ret;
1212
1213	rbd_dev->mapping.size = size;
1214	return 0;
1215}
1216
1217static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1218{
1219	rbd_dev->mapping.size = 0;
1220}
1221
1222static void zero_bvec(struct bio_vec *bv)
1223{
1224	void *buf;
1225	unsigned long flags;
1226
1227	buf = bvec_kmap_irq(bv, &flags);
1228	memset(buf, 0, bv->bv_len);
1229	flush_dcache_page(bv->bv_page);
1230	bvec_kunmap_irq(buf, &flags);
1231}
1232
1233static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
1234{
1235	struct ceph_bio_iter it = *bio_pos;
1236
1237	ceph_bio_iter_advance(&it, off);
1238	ceph_bio_iter_advance_step(&it, bytes, ({
1239		zero_bvec(&bv);
1240	}));
1241}
1242
1243static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
1244{
1245	struct ceph_bvec_iter it = *bvec_pos;
1246
1247	ceph_bvec_iter_advance(&it, off);
1248	ceph_bvec_iter_advance_step(&it, bytes, ({
1249		zero_bvec(&bv);
1250	}));
1251}
1252
1253/*
1254 * Zero a range in @obj_req data buffer defined by a bio (list) or
1255 * (private) bio_vec array.
1256 *
1257 * @off is relative to the start of the data buffer.
1258 */
1259static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off,
1260			       u32 bytes)
 
 
1261{
1262	dout("%s %p data buf %u~%u\n", __func__, obj_req, off, bytes);
1263
1264	switch (obj_req->img_request->data_type) {
1265	case OBJ_REQUEST_BIO:
1266		zero_bios(&obj_req->bio_pos, off, bytes);
1267		break;
1268	case OBJ_REQUEST_BVECS:
1269	case OBJ_REQUEST_OWN_BVECS:
1270		zero_bvecs(&obj_req->bvec_pos, off, bytes);
1271		break;
1272	default:
1273		BUG();
1274	}
1275}
1276
1277static void rbd_obj_request_destroy(struct kref *kref);
1278static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1279{
1280	rbd_assert(obj_request != NULL);
1281	dout("%s: obj %p (was %d)\n", __func__, obj_request,
1282		kref_read(&obj_request->kref));
1283	kref_put(&obj_request->kref, rbd_obj_request_destroy);
1284}
1285
1286static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1287					struct rbd_obj_request *obj_request)
1288{
1289	rbd_assert(obj_request->img_request == NULL);
1290
1291	/* Image request now owns object's original reference */
1292	obj_request->img_request = img_request;
1293	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1294}
1295
1296static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1297					struct rbd_obj_request *obj_request)
1298{
1299	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1300	list_del(&obj_request->ex.oe_item);
1301	rbd_assert(obj_request->img_request == img_request);
1302	rbd_obj_request_put(obj_request);
1303}
1304
1305static void rbd_osd_submit(struct ceph_osd_request *osd_req)
 
1306{
1307	struct rbd_obj_request *obj_req = osd_req->r_priv;
1308
1309	dout("%s osd_req %p for obj_req %p objno %llu %llu~%llu\n",
1310	     __func__, osd_req, obj_req, obj_req->ex.oe_objno,
1311	     obj_req->ex.oe_off, obj_req->ex.oe_len);
1312	ceph_osdc_start_request(osd_req->r_osdc, osd_req, false);
1313}
1314
1315/*
1316 * The default/initial value for all image request flags is 0.  Each
1317 * is conditionally set to 1 at image request initialization time
1318 * and currently never change thereafter.
1319 */
1320static void img_request_layered_set(struct rbd_img_request *img_request)
1321{
1322	set_bit(IMG_REQ_LAYERED, &img_request->flags);
1323}
1324
1325static bool img_request_layered_test(struct rbd_img_request *img_request)
1326{
1327	return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1328}
1329
1330static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req)
1331{
1332	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1333
1334	return !obj_req->ex.oe_off &&
1335	       obj_req->ex.oe_len == rbd_dev->layout.object_size;
1336}
1337
1338static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req)
1339{
1340	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1341
1342	return obj_req->ex.oe_off + obj_req->ex.oe_len ==
1343					rbd_dev->layout.object_size;
1344}
1345
1346/*
1347 * Must be called after rbd_obj_calc_img_extents().
1348 */
1349static bool rbd_obj_copyup_enabled(struct rbd_obj_request *obj_req)
1350{
1351	if (!obj_req->num_img_extents ||
1352	    (rbd_obj_is_entire(obj_req) &&
1353	     !obj_req->img_request->snapc->num_snaps))
1354		return false;
1355
1356	return true;
1357}
1358
1359static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req)
1360{
1361	return ceph_file_extents_bytes(obj_req->img_extents,
1362				       obj_req->num_img_extents);
1363}
1364
1365static bool rbd_img_is_write(struct rbd_img_request *img_req)
1366{
1367	switch (img_req->op_type) {
1368	case OBJ_OP_READ:
1369		return false;
1370	case OBJ_OP_WRITE:
1371	case OBJ_OP_DISCARD:
1372	case OBJ_OP_ZEROOUT:
1373		return true;
1374	default:
1375		BUG();
1376	}
1377}
1378
1379static void rbd_osd_req_callback(struct ceph_osd_request *osd_req)
1380{
1381	struct rbd_obj_request *obj_req = osd_req->r_priv;
1382	int result;
1383
1384	dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
1385	     osd_req->r_result, obj_req);
1386
1387	/*
1388	 * Writes aren't allowed to return a data payload.  In some
1389	 * guarded write cases (e.g. stat + zero on an empty object)
1390	 * a stat response makes it through, but we don't care.
1391	 */
1392	if (osd_req->r_result > 0 && rbd_img_is_write(obj_req->img_request))
1393		result = 0;
1394	else
1395		result = osd_req->r_result;
1396
1397	rbd_obj_handle_request(obj_req, result);
1398}
1399
1400static void rbd_osd_format_read(struct ceph_osd_request *osd_req)
1401{
1402	struct rbd_obj_request *obj_request = osd_req->r_priv;
1403	struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1404	struct ceph_options *opt = rbd_dev->rbd_client->client->options;
1405
1406	osd_req->r_flags = CEPH_OSD_FLAG_READ | opt->read_from_replica;
1407	osd_req->r_snapid = obj_request->img_request->snap_id;
1408}
1409
1410static void rbd_osd_format_write(struct ceph_osd_request *osd_req)
1411{
1412	struct rbd_obj_request *obj_request = osd_req->r_priv;
1413
1414	osd_req->r_flags = CEPH_OSD_FLAG_WRITE;
1415	ktime_get_real_ts64(&osd_req->r_mtime);
1416	osd_req->r_data_offset = obj_request->ex.oe_off;
1417}
1418
1419static struct ceph_osd_request *
1420__rbd_obj_add_osd_request(struct rbd_obj_request *obj_req,
1421			  struct ceph_snap_context *snapc, int num_ops)
1422{
1423	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1424	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1425	struct ceph_osd_request *req;
1426	const char *name_format = rbd_dev->image_format == 1 ?
1427				      RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT;
1428	int ret;
1429
1430	req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, GFP_NOIO);
1431	if (!req)
1432		return ERR_PTR(-ENOMEM);
1433
1434	list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
1435	req->r_callback = rbd_osd_req_callback;
1436	req->r_priv = obj_req;
1437
1438	/*
1439	 * Data objects may be stored in a separate pool, but always in
1440	 * the same namespace in that pool as the header in its pool.
1441	 */
1442	ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
1443	req->r_base_oloc.pool = rbd_dev->layout.pool_id;
1444
1445	ret = ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format,
1446			       rbd_dev->header.object_prefix,
1447			       obj_req->ex.oe_objno);
1448	if (ret)
1449		return ERR_PTR(ret);
1450
1451	return req;
1452}
1453
1454static struct ceph_osd_request *
1455rbd_obj_add_osd_request(struct rbd_obj_request *obj_req, int num_ops)
1456{
1457	return __rbd_obj_add_osd_request(obj_req, obj_req->img_request->snapc,
1458					 num_ops);
1459}
1460
1461static struct rbd_obj_request *rbd_obj_request_create(void)
1462{
1463	struct rbd_obj_request *obj_request;
1464
1465	obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
1466	if (!obj_request)
1467		return NULL;
1468
1469	ceph_object_extent_init(&obj_request->ex);
1470	INIT_LIST_HEAD(&obj_request->osd_reqs);
1471	mutex_init(&obj_request->state_mutex);
1472	kref_init(&obj_request->kref);
1473
1474	dout("%s %p\n", __func__, obj_request);
1475	return obj_request;
1476}
1477
1478static void rbd_obj_request_destroy(struct kref *kref)
1479{
1480	struct rbd_obj_request *obj_request;
1481	struct ceph_osd_request *osd_req;
1482	u32 i;
1483
1484	obj_request = container_of(kref, struct rbd_obj_request, kref);
1485
1486	dout("%s: obj %p\n", __func__, obj_request);
1487
1488	while (!list_empty(&obj_request->osd_reqs)) {
1489		osd_req = list_first_entry(&obj_request->osd_reqs,
1490				    struct ceph_osd_request, r_private_item);
1491		list_del_init(&osd_req->r_private_item);
1492		ceph_osdc_put_request(osd_req);
1493	}
1494
1495	switch (obj_request->img_request->data_type) {
1496	case OBJ_REQUEST_NODATA:
1497	case OBJ_REQUEST_BIO:
1498	case OBJ_REQUEST_BVECS:
1499		break;		/* Nothing to do */
1500	case OBJ_REQUEST_OWN_BVECS:
1501		kfree(obj_request->bvec_pos.bvecs);
1502		break;
1503	default:
1504		BUG();
1505	}
1506
1507	kfree(obj_request->img_extents);
1508	if (obj_request->copyup_bvecs) {
1509		for (i = 0; i < obj_request->copyup_bvec_count; i++) {
1510			if (obj_request->copyup_bvecs[i].bv_page)
1511				__free_page(obj_request->copyup_bvecs[i].bv_page);
1512		}
1513		kfree(obj_request->copyup_bvecs);
1514	}
1515
1516	kmem_cache_free(rbd_obj_request_cache, obj_request);
1517}
1518
1519/* It's OK to call this for a device with no parent */
1520
1521static void rbd_spec_put(struct rbd_spec *spec);
1522static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1523{
1524	rbd_dev_remove_parent(rbd_dev);
1525	rbd_spec_put(rbd_dev->parent_spec);
1526	rbd_dev->parent_spec = NULL;
1527	rbd_dev->parent_overlap = 0;
1528}
1529
1530/*
1531 * Parent image reference counting is used to determine when an
1532 * image's parent fields can be safely torn down--after there are no
1533 * more in-flight requests to the parent image.  When the last
1534 * reference is dropped, cleaning them up is safe.
1535 */
1536static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1537{
1538	int counter;
 
 
 
 
1539
1540	if (!rbd_dev->parent_spec)
1541		return;
 
 
 
 
 
 
 
 
 
1542
1543	counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1544	if (counter > 0)
1545		return;
1546
1547	/* Last reference; clean up parent data structures */
1548
1549	if (!counter)
1550		rbd_dev_unparent(rbd_dev);
1551	else
1552		rbd_warn(rbd_dev, "parent reference underflow");
1553}
1554
1555/*
1556 * If an image has a non-zero parent overlap, get a reference to its
1557 * parent.
1558 *
1559 * Returns true if the rbd device has a parent with a non-zero
1560 * overlap and a reference for it was successfully taken, or
1561 * false otherwise.
1562 */
1563static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
 
 
1564{
1565	int counter = 0;
 
1566
1567	if (!rbd_dev->parent_spec)
1568		return false;
 
 
1569
1570	if (rbd_dev->parent_overlap)
1571		counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
 
 
1572
1573	if (counter < 0)
1574		rbd_warn(rbd_dev, "parent reference overflow");
1575
1576	return counter > 0;
1577}
 
 
 
 
 
 
 
 
 
 
 
 
1578
1579static void rbd_img_request_init(struct rbd_img_request *img_request,
1580				 struct rbd_device *rbd_dev,
1581				 enum obj_operation_type op_type)
1582{
1583	memset(img_request, 0, sizeof(*img_request));
1584
1585	img_request->rbd_dev = rbd_dev;
1586	img_request->op_type = op_type;
 
 
 
1587
1588	INIT_LIST_HEAD(&img_request->lock_item);
1589	INIT_LIST_HEAD(&img_request->object_extents);
1590	mutex_init(&img_request->state_mutex);
1591}
1592
1593static void rbd_img_capture_header(struct rbd_img_request *img_req)
1594{
1595	struct rbd_device *rbd_dev = img_req->rbd_dev;
 
 
 
 
1596
1597	lockdep_assert_held(&rbd_dev->header_rwsem);
1598
1599	if (rbd_img_is_write(img_req))
1600		img_req->snapc = ceph_get_snap_context(rbd_dev->header.snapc);
1601	else
1602		img_req->snap_id = rbd_dev->spec->snap_id;
1603
1604	if (rbd_dev_parent_get(rbd_dev))
1605		img_request_layered_set(img_req);
1606}
1607
1608static void rbd_img_request_destroy(struct rbd_img_request *img_request)
1609{
1610	struct rbd_obj_request *obj_request;
1611	struct rbd_obj_request *next_obj_request;
1612
1613	dout("%s: img %p\n", __func__, img_request);
1614
1615	WARN_ON(!list_empty(&img_request->lock_item));
1616	for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1617		rbd_img_obj_request_del(img_request, obj_request);
1618
1619	if (img_request_layered_test(img_request))
1620		rbd_dev_parent_put(img_request->rbd_dev);
1621
1622	if (rbd_img_is_write(img_request))
1623		ceph_put_snap_context(img_request->snapc);
1624
1625	if (test_bit(IMG_REQ_CHILD, &img_request->flags))
1626		kmem_cache_free(rbd_img_request_cache, img_request);
1627}
1628
1629#define BITS_PER_OBJ	2
1630#define OBJS_PER_BYTE	(BITS_PER_BYTE / BITS_PER_OBJ)
1631#define OBJ_MASK	((1 << BITS_PER_OBJ) - 1)
1632
1633static void __rbd_object_map_index(struct rbd_device *rbd_dev, u64 objno,
1634				   u64 *index, u8 *shift)
1635{
1636	u32 off;
1637
1638	rbd_assert(objno < rbd_dev->object_map_size);
1639	*index = div_u64_rem(objno, OBJS_PER_BYTE, &off);
1640	*shift = (OBJS_PER_BYTE - off - 1) * BITS_PER_OBJ;
1641}
1642
1643static u8 __rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1644{
1645	u64 index;
1646	u8 shift;
1647
1648	lockdep_assert_held(&rbd_dev->object_map_lock);
1649	__rbd_object_map_index(rbd_dev, objno, &index, &shift);
1650	return (rbd_dev->object_map[index] >> shift) & OBJ_MASK;
1651}
1652
1653static void __rbd_object_map_set(struct rbd_device *rbd_dev, u64 objno, u8 val)
1654{
1655	u64 index;
1656	u8 shift;
1657	u8 *p;
1658
1659	lockdep_assert_held(&rbd_dev->object_map_lock);
1660	rbd_assert(!(val & ~OBJ_MASK));
1661
1662	__rbd_object_map_index(rbd_dev, objno, &index, &shift);
1663	p = &rbd_dev->object_map[index];
1664	*p = (*p & ~(OBJ_MASK << shift)) | (val << shift);
1665}
1666
1667static u8 rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1668{
1669	u8 state;
1670
1671	spin_lock(&rbd_dev->object_map_lock);
1672	state = __rbd_object_map_get(rbd_dev, objno);
1673	spin_unlock(&rbd_dev->object_map_lock);
1674	return state;
1675}
1676
1677static bool use_object_map(struct rbd_device *rbd_dev)
1678{
1679	/*
1680	 * An image mapped read-only can't use the object map -- it isn't
1681	 * loaded because the header lock isn't acquired.  Someone else can
1682	 * write to the image and update the object map behind our back.
1683	 *
1684	 * A snapshot can't be written to, so using the object map is always
1685	 * safe.
1686	 */
1687	if (!rbd_is_snap(rbd_dev) && rbd_is_ro(rbd_dev))
1688		return false;
1689
1690	return ((rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) &&
1691		!(rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID));
1692}
1693
1694static bool rbd_object_map_may_exist(struct rbd_device *rbd_dev, u64 objno)
1695{
1696	u8 state;
1697
1698	/* fall back to default logic if object map is disabled or invalid */
1699	if (!use_object_map(rbd_dev))
1700		return true;
1701
1702	state = rbd_object_map_get(rbd_dev, objno);
1703	return state != OBJECT_NONEXISTENT;
1704}
1705
1706static void rbd_object_map_name(struct rbd_device *rbd_dev, u64 snap_id,
1707				struct ceph_object_id *oid)
 
 
1708{
1709	if (snap_id == CEPH_NOSNAP)
1710		ceph_oid_printf(oid, "%s%s", RBD_OBJECT_MAP_PREFIX,
1711				rbd_dev->spec->image_id);
1712	else
1713		ceph_oid_printf(oid, "%s%s.%016llx", RBD_OBJECT_MAP_PREFIX,
1714				rbd_dev->spec->image_id, snap_id);
1715}
1716
1717static int rbd_object_map_lock(struct rbd_device *rbd_dev)
1718{
1719	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1720	CEPH_DEFINE_OID_ONSTACK(oid);
1721	u8 lock_type;
1722	char *lock_tag;
1723	struct ceph_locker *lockers;
1724	u32 num_lockers;
1725	bool broke_lock = false;
1726	int ret;
1727
1728	rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
 
1729
1730again:
1731	ret = ceph_cls_lock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1732			    CEPH_CLS_LOCK_EXCLUSIVE, "", "", "", 0);
1733	if (ret != -EBUSY || broke_lock) {
1734		if (ret == -EEXIST)
1735			ret = 0; /* already locked by myself */
1736		if (ret)
1737			rbd_warn(rbd_dev, "failed to lock object map: %d", ret);
1738		return ret;
1739	}
1740
1741	ret = ceph_cls_lock_info(osdc, &oid, &rbd_dev->header_oloc,
1742				 RBD_LOCK_NAME, &lock_type, &lock_tag,
1743				 &lockers, &num_lockers);
1744	if (ret) {
1745		if (ret == -ENOENT)
1746			goto again;
1747
1748		rbd_warn(rbd_dev, "failed to get object map lockers: %d", ret);
1749		return ret;
1750	}
1751
1752	kfree(lock_tag);
1753	if (num_lockers == 0)
1754		goto again;
1755
1756	rbd_warn(rbd_dev, "breaking object map lock owned by %s%llu",
1757		 ENTITY_NAME(lockers[0].id.name));
1758
1759	ret = ceph_cls_break_lock(osdc, &oid, &rbd_dev->header_oloc,
1760				  RBD_LOCK_NAME, lockers[0].id.cookie,
1761				  &lockers[0].id.name);
1762	ceph_free_lockers(lockers, num_lockers);
1763	if (ret) {
1764		if (ret == -ENOENT)
1765			goto again;
1766
1767		rbd_warn(rbd_dev, "failed to break object map lock: %d", ret);
1768		return ret;
1769	}
1770
1771	broke_lock = true;
1772	goto again;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1773}
1774
1775static void rbd_object_map_unlock(struct rbd_device *rbd_dev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1776{
1777	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1778	CEPH_DEFINE_OID_ONSTACK(oid);
1779	int ret;
1780
1781	rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
1782
1783	ret = ceph_cls_unlock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1784			      "");
1785	if (ret && ret != -ENOENT)
1786		rbd_warn(rbd_dev, "failed to unlock object map: %d", ret);
1787}
1788
1789static int decode_object_map_header(void **p, void *end, u64 *object_map_size)
1790{
1791	u8 struct_v;
1792	u32 struct_len;
1793	u32 header_len;
1794	void *header_end;
1795	int ret;
1796
1797	ceph_decode_32_safe(p, end, header_len, e_inval);
1798	header_end = *p + header_len;
1799
1800	ret = ceph_start_decoding(p, end, 1, "BitVector header", &struct_v,
1801				  &struct_len);
1802	if (ret)
1803		return ret;
1804
1805	ceph_decode_64_safe(p, end, *object_map_size, e_inval);
1806
1807	*p = header_end;
1808	return 0;
1809
1810e_inval:
1811	return -EINVAL;
1812}
1813
1814static int __rbd_object_map_load(struct rbd_device *rbd_dev)
1815{
1816	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1817	CEPH_DEFINE_OID_ONSTACK(oid);
1818	struct page **pages;
1819	void *p, *end;
1820	size_t reply_len;
1821	u64 num_objects;
1822	u64 object_map_bytes;
1823	u64 object_map_size;
1824	int num_pages;
1825	int ret;
1826
1827	rbd_assert(!rbd_dev->object_map && !rbd_dev->object_map_size);
1828
1829	num_objects = ceph_get_num_objects(&rbd_dev->layout,
1830					   rbd_dev->mapping.size);
1831	object_map_bytes = DIV_ROUND_UP_ULL(num_objects * BITS_PER_OBJ,
1832					    BITS_PER_BYTE);
1833	num_pages = calc_pages_for(0, object_map_bytes) + 1;
1834	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1835	if (IS_ERR(pages))
1836		return PTR_ERR(pages);
1837
1838	reply_len = num_pages * PAGE_SIZE;
1839	rbd_object_map_name(rbd_dev, rbd_dev->spec->snap_id, &oid);
1840	ret = ceph_osdc_call(osdc, &oid, &rbd_dev->header_oloc,
1841			     "rbd", "object_map_load", CEPH_OSD_FLAG_READ,
1842			     NULL, 0, pages, &reply_len);
1843	if (ret)
1844		goto out;
1845
1846	p = page_address(pages[0]);
1847	end = p + min(reply_len, (size_t)PAGE_SIZE);
1848	ret = decode_object_map_header(&p, end, &object_map_size);
1849	if (ret)
1850		goto out;
1851
1852	if (object_map_size != num_objects) {
1853		rbd_warn(rbd_dev, "object map size mismatch: %llu vs %llu",
1854			 object_map_size, num_objects);
1855		ret = -EINVAL;
1856		goto out;
1857	}
1858
1859	if (offset_in_page(p) + object_map_bytes > reply_len) {
1860		ret = -EINVAL;
1861		goto out;
1862	}
1863
1864	rbd_dev->object_map = kvmalloc(object_map_bytes, GFP_KERNEL);
1865	if (!rbd_dev->object_map) {
 
 
 
 
 
 
 
 
 
1866		ret = -ENOMEM;
1867		goto out;
1868	}
1869
1870	rbd_dev->object_map_size = object_map_size;
1871	ceph_copy_from_page_vector(pages, rbd_dev->object_map,
1872				   offset_in_page(p), object_map_bytes);
1873
1874out:
1875	ceph_release_page_vector(pages, num_pages);
1876	return ret;
1877}
1878
1879static void rbd_object_map_free(struct rbd_device *rbd_dev)
1880{
1881	kvfree(rbd_dev->object_map);
1882	rbd_dev->object_map = NULL;
1883	rbd_dev->object_map_size = 0;
1884}
1885
1886static int rbd_object_map_load(struct rbd_device *rbd_dev)
1887{
1888	int ret;
1889
1890	ret = __rbd_object_map_load(rbd_dev);
1891	if (ret)
1892		return ret;
1893
1894	ret = rbd_dev_v2_get_flags(rbd_dev);
1895	if (ret) {
1896		rbd_object_map_free(rbd_dev);
1897		return ret;
1898	}
1899
1900	if (rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID)
1901		rbd_warn(rbd_dev, "object map is invalid");
1902
1903	return 0;
1904}
1905
1906static int rbd_object_map_open(struct rbd_device *rbd_dev)
1907{
1908	int ret;
 
 
 
 
 
 
1909
1910	ret = rbd_object_map_lock(rbd_dev);
1911	if (ret)
1912		return ret;
 
 
 
1913
1914	ret = rbd_object_map_load(rbd_dev);
1915	if (ret) {
1916		rbd_object_map_unlock(rbd_dev);
1917		return ret;
1918	}
1919
1920	return 0;
1921}
1922
1923static void rbd_object_map_close(struct rbd_device *rbd_dev)
1924{
1925	rbd_object_map_free(rbd_dev);
1926	rbd_object_map_unlock(rbd_dev);
1927}
1928
1929/*
1930 * This function needs snap_id (or more precisely just something to
1931 * distinguish between HEAD and snapshot object maps), new_state and
1932 * current_state that were passed to rbd_object_map_update().
1933 *
1934 * To avoid allocating and stashing a context we piggyback on the OSD
1935 * request.  A HEAD update has two ops (assert_locked).  For new_state
1936 * and current_state we decode our own object_map_update op, encoded in
1937 * rbd_cls_object_map_update().
1938 */
1939static int rbd_object_map_update_finish(struct rbd_obj_request *obj_req,
1940					struct ceph_osd_request *osd_req)
1941{
1942	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1943	struct ceph_osd_data *osd_data;
1944	u64 objno;
1945	u8 state, new_state, current_state;
1946	bool has_current_state;
1947	void *p;
1948
1949	if (osd_req->r_result)
1950		return osd_req->r_result;
1951
1952	/*
1953	 * Nothing to do for a snapshot object map.
1954	 */
1955	if (osd_req->r_num_ops == 1)
1956		return 0;
1957
1958	/*
1959	 * Update in-memory HEAD object map.
1960	 */
1961	rbd_assert(osd_req->r_num_ops == 2);
1962	osd_data = osd_req_op_data(osd_req, 1, cls, request_data);
1963	rbd_assert(osd_data->type == CEPH_OSD_DATA_TYPE_PAGES);
1964
1965	p = page_address(osd_data->pages[0]);
1966	objno = ceph_decode_64(&p);
1967	rbd_assert(objno == obj_req->ex.oe_objno);
1968	rbd_assert(ceph_decode_64(&p) == objno + 1);
1969	new_state = ceph_decode_8(&p);
1970	has_current_state = ceph_decode_8(&p);
1971	if (has_current_state)
1972		current_state = ceph_decode_8(&p);
1973
1974	spin_lock(&rbd_dev->object_map_lock);
1975	state = __rbd_object_map_get(rbd_dev, objno);
1976	if (!has_current_state || current_state == state ||
1977	    (current_state == OBJECT_EXISTS && state == OBJECT_EXISTS_CLEAN))
1978		__rbd_object_map_set(rbd_dev, objno, new_state);
1979	spin_unlock(&rbd_dev->object_map_lock);
1980
1981	return 0;
1982}
1983
1984static void rbd_object_map_callback(struct ceph_osd_request *osd_req)
1985{
1986	struct rbd_obj_request *obj_req = osd_req->r_priv;
1987	int result;
1988
1989	dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
1990	     osd_req->r_result, obj_req);
1991
1992	result = rbd_object_map_update_finish(obj_req, osd_req);
1993	rbd_obj_handle_request(obj_req, result);
1994}
1995
1996static bool update_needed(struct rbd_device *rbd_dev, u64 objno, u8 new_state)
1997{
1998	u8 state = rbd_object_map_get(rbd_dev, objno);
1999
2000	if (state == new_state ||
2001	    (new_state == OBJECT_PENDING && state == OBJECT_NONEXISTENT) ||
2002	    (new_state == OBJECT_NONEXISTENT && state != OBJECT_PENDING))
2003		return false;
2004
2005	return true;
2006}
2007
2008static int rbd_cls_object_map_update(struct ceph_osd_request *req,
2009				     int which, u64 objno, u8 new_state,
2010				     const u8 *current_state)
2011{
2012	struct page **pages;
2013	void *p, *start;
2014	int ret;
2015
2016	ret = osd_req_op_cls_init(req, which, "rbd", "object_map_update");
2017	if (ret)
2018		return ret;
2019
2020	pages = ceph_alloc_page_vector(1, GFP_NOIO);
2021	if (IS_ERR(pages))
2022		return PTR_ERR(pages);
2023
2024	p = start = page_address(pages[0]);
2025	ceph_encode_64(&p, objno);
2026	ceph_encode_64(&p, objno + 1);
2027	ceph_encode_8(&p, new_state);
2028	if (current_state) {
2029		ceph_encode_8(&p, 1);
2030		ceph_encode_8(&p, *current_state);
2031	} else {
2032		ceph_encode_8(&p, 0);
2033	}
 
2034
2035	osd_req_op_cls_request_data_pages(req, which, pages, p - start, 0,
2036					  false, true);
2037	return 0;
 
 
 
 
2038}
2039
2040/*
2041 * Return:
2042 *   0 - object map update sent
2043 *   1 - object map update isn't needed
2044 *  <0 - error
2045 */
2046static int rbd_object_map_update(struct rbd_obj_request *obj_req, u64 snap_id,
2047				 u8 new_state, const u8 *current_state)
2048{
2049	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2050	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2051	struct ceph_osd_request *req;
2052	int num_ops = 1;
2053	int which = 0;
2054	int ret;
2055
2056	if (snap_id == CEPH_NOSNAP) {
2057		if (!update_needed(rbd_dev, obj_req->ex.oe_objno, new_state))
2058			return 1;
 
 
 
 
2059
2060		num_ops++; /* assert_locked */
2061	}
2062
2063	req = ceph_osdc_alloc_request(osdc, NULL, num_ops, false, GFP_NOIO);
2064	if (!req)
2065		return -ENOMEM;
2066
2067	list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
2068	req->r_callback = rbd_object_map_callback;
2069	req->r_priv = obj_req;
2070
2071	rbd_object_map_name(rbd_dev, snap_id, &req->r_base_oid);
2072	ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
2073	req->r_flags = CEPH_OSD_FLAG_WRITE;
2074	ktime_get_real_ts64(&req->r_mtime);
2075
2076	if (snap_id == CEPH_NOSNAP) {
2077		/*
2078		 * Protect against possible race conditions during lock
2079		 * ownership transitions.
2080		 */
2081		ret = ceph_cls_assert_locked(req, which++, RBD_LOCK_NAME,
2082					     CEPH_CLS_LOCK_EXCLUSIVE, "", "");
2083		if (ret)
2084			return ret;
2085	}
2086
2087	ret = rbd_cls_object_map_update(req, which, obj_req->ex.oe_objno,
2088					new_state, current_state);
2089	if (ret)
2090		return ret;
2091
2092	ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
2093	if (ret)
2094		return ret;
2095
2096	ceph_osdc_start_request(osdc, req, false);
2097	return 0;
2098}
2099
2100static void prune_extents(struct ceph_file_extent *img_extents,
2101			  u32 *num_img_extents, u64 overlap)
2102{
2103	u32 cnt = *num_img_extents;
2104
2105	/* drop extents completely beyond the overlap */
2106	while (cnt && img_extents[cnt - 1].fe_off >= overlap)
2107		cnt--;
2108
2109	if (cnt) {
2110		struct ceph_file_extent *ex = &img_extents[cnt - 1];
2111
2112		/* trim final overlapping extent */
2113		if (ex->fe_off + ex->fe_len > overlap)
2114			ex->fe_len = overlap - ex->fe_off;
2115	}
2116
2117	*num_img_extents = cnt;
2118}
2119
2120/*
2121 * Determine the byte range(s) covered by either just the object extent
2122 * or the entire object in the parent image.
2123 */
2124static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req,
2125				    bool entire)
 
 
 
 
 
 
 
 
 
 
2126{
2127	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2128	int ret;
2129
2130	if (!rbd_dev->parent_overlap)
2131		return 0;
2132
2133	ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno,
2134				  entire ? 0 : obj_req->ex.oe_off,
2135				  entire ? rbd_dev->layout.object_size :
2136							obj_req->ex.oe_len,
2137				  &obj_req->img_extents,
2138				  &obj_req->num_img_extents);
2139	if (ret)
2140		return ret;
2141
2142	prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
2143		      rbd_dev->parent_overlap);
2144	return 0;
2145}
2146
2147static void rbd_osd_setup_data(struct ceph_osd_request *osd_req, int which)
2148{
2149	struct rbd_obj_request *obj_req = osd_req->r_priv;
2150
2151	switch (obj_req->img_request->data_type) {
2152	case OBJ_REQUEST_BIO:
2153		osd_req_op_extent_osd_data_bio(osd_req, which,
2154					       &obj_req->bio_pos,
2155					       obj_req->ex.oe_len);
2156		break;
2157	case OBJ_REQUEST_BVECS:
2158	case OBJ_REQUEST_OWN_BVECS:
2159		rbd_assert(obj_req->bvec_pos.iter.bi_size ==
2160							obj_req->ex.oe_len);
2161		rbd_assert(obj_req->bvec_idx == obj_req->bvec_count);
2162		osd_req_op_extent_osd_data_bvec_pos(osd_req, which,
2163						    &obj_req->bvec_pos);
2164		break;
2165	default:
2166		BUG();
2167	}
2168}
2169
2170static int rbd_osd_setup_stat(struct ceph_osd_request *osd_req, int which)
2171{
2172	struct page **pages;
 
 
 
2173
2174	/*
2175	 * The response data for a STAT call consists of:
2176	 *     le64 length;
2177	 *     struct {
2178	 *         le32 tv_sec;
2179	 *         le32 tv_nsec;
2180	 *     } mtime;
2181	 */
2182	pages = ceph_alloc_page_vector(1, GFP_NOIO);
2183	if (IS_ERR(pages))
2184		return PTR_ERR(pages);
2185
2186	osd_req_op_init(osd_req, which, CEPH_OSD_OP_STAT, 0);
2187	osd_req_op_raw_data_in_pages(osd_req, which, pages,
2188				     8 + sizeof(struct ceph_timespec),
2189				     0, false, true);
2190	return 0;
2191}
2192
2193static int rbd_osd_setup_copyup(struct ceph_osd_request *osd_req, int which,
2194				u32 bytes)
2195{
2196	struct rbd_obj_request *obj_req = osd_req->r_priv;
2197	int ret;
2198
2199	ret = osd_req_op_cls_init(osd_req, which, "rbd", "copyup");
2200	if (ret)
2201		return ret;
2202
2203	osd_req_op_cls_request_data_bvecs(osd_req, which, obj_req->copyup_bvecs,
2204					  obj_req->copyup_bvec_count, bytes);
2205	return 0;
2206}
2207
2208static int rbd_obj_init_read(struct rbd_obj_request *obj_req)
2209{
2210	obj_req->read_state = RBD_OBJ_READ_START;
2211	return 0;
2212}
2213
2214static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2215				      int which)
2216{
2217	struct rbd_obj_request *obj_req = osd_req->r_priv;
2218	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2219	u16 opcode;
2220
2221	if (!use_object_map(rbd_dev) ||
2222	    !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST)) {
2223		osd_req_op_alloc_hint_init(osd_req, which++,
2224					   rbd_dev->layout.object_size,
2225					   rbd_dev->layout.object_size,
2226					   rbd_dev->opts->alloc_hint_flags);
2227	}
2228
2229	if (rbd_obj_is_entire(obj_req))
2230		opcode = CEPH_OSD_OP_WRITEFULL;
2231	else
2232		opcode = CEPH_OSD_OP_WRITE;
2233
2234	osd_req_op_extent_init(osd_req, which, opcode,
2235			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2236	rbd_osd_setup_data(osd_req, which);
2237}
2238
2239static int rbd_obj_init_write(struct rbd_obj_request *obj_req)
2240{
2241	int ret;
2242
2243	/* reverse map the entire object onto the parent */
2244	ret = rbd_obj_calc_img_extents(obj_req, true);
2245	if (ret)
2246		return ret;
2247
2248	if (rbd_obj_copyup_enabled(obj_req))
2249		obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
2250
2251	obj_req->write_state = RBD_OBJ_WRITE_START;
2252	return 0;
2253}
2254
2255static u16 truncate_or_zero_opcode(struct rbd_obj_request *obj_req)
2256{
2257	return rbd_obj_is_tail(obj_req) ? CEPH_OSD_OP_TRUNCATE :
2258					  CEPH_OSD_OP_ZERO;
2259}
2260
2261static void __rbd_osd_setup_discard_ops(struct ceph_osd_request *osd_req,
2262					int which)
2263{
2264	struct rbd_obj_request *obj_req = osd_req->r_priv;
2265
2266	if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents) {
2267		rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2268		osd_req_op_init(osd_req, which, CEPH_OSD_OP_DELETE, 0);
2269	} else {
2270		osd_req_op_extent_init(osd_req, which,
2271				       truncate_or_zero_opcode(obj_req),
2272				       obj_req->ex.oe_off, obj_req->ex.oe_len,
2273				       0, 0);
2274	}
2275}
2276
2277static int rbd_obj_init_discard(struct rbd_obj_request *obj_req)
2278{
2279	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2280	u64 off, next_off;
2281	int ret;
2282
2283	/*
2284	 * Align the range to alloc_size boundary and punt on discards
2285	 * that are too small to free up any space.
2286	 *
2287	 * alloc_size == object_size && is_tail() is a special case for
2288	 * filestore with filestore_punch_hole = false, needed to allow
2289	 * truncate (in addition to delete).
2290	 */
2291	if (rbd_dev->opts->alloc_size != rbd_dev->layout.object_size ||
2292	    !rbd_obj_is_tail(obj_req)) {
2293		off = round_up(obj_req->ex.oe_off, rbd_dev->opts->alloc_size);
2294		next_off = round_down(obj_req->ex.oe_off + obj_req->ex.oe_len,
2295				      rbd_dev->opts->alloc_size);
2296		if (off >= next_off)
2297			return 1;
2298
2299		dout("%s %p %llu~%llu -> %llu~%llu\n", __func__,
2300		     obj_req, obj_req->ex.oe_off, obj_req->ex.oe_len,
2301		     off, next_off - off);
2302		obj_req->ex.oe_off = off;
2303		obj_req->ex.oe_len = next_off - off;
2304	}
2305
2306	/* reverse map the entire object onto the parent */
2307	ret = rbd_obj_calc_img_extents(obj_req, true);
2308	if (ret)
2309		return ret;
2310
2311	obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2312	if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents)
2313		obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2314
2315	obj_req->write_state = RBD_OBJ_WRITE_START;
2316	return 0;
2317}
2318
2319static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req,
2320					int which)
2321{
2322	struct rbd_obj_request *obj_req = osd_req->r_priv;
2323	u16 opcode;
2324
2325	if (rbd_obj_is_entire(obj_req)) {
2326		if (obj_req->num_img_extents) {
2327			if (!(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2328				osd_req_op_init(osd_req, which++,
2329						CEPH_OSD_OP_CREATE, 0);
2330			opcode = CEPH_OSD_OP_TRUNCATE;
2331		} else {
2332			rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2333			osd_req_op_init(osd_req, which++,
2334					CEPH_OSD_OP_DELETE, 0);
2335			opcode = 0;
2336		}
2337	} else {
2338		opcode = truncate_or_zero_opcode(obj_req);
2339	}
2340
2341	if (opcode)
2342		osd_req_op_extent_init(osd_req, which, opcode,
2343				       obj_req->ex.oe_off, obj_req->ex.oe_len,
2344				       0, 0);
2345}
 
 
 
 
 
 
2346
2347static int rbd_obj_init_zeroout(struct rbd_obj_request *obj_req)
2348{
2349	int ret;
2350
2351	/* reverse map the entire object onto the parent */
2352	ret = rbd_obj_calc_img_extents(obj_req, true);
2353	if (ret)
2354		return ret;
2355
2356	if (rbd_obj_copyup_enabled(obj_req))
2357		obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
2358	if (!obj_req->num_img_extents) {
2359		obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2360		if (rbd_obj_is_entire(obj_req))
2361			obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2362	}
2363
2364	obj_req->write_state = RBD_OBJ_WRITE_START;
2365	return 0;
2366}
2367
2368static int count_write_ops(struct rbd_obj_request *obj_req)
2369{
2370	struct rbd_img_request *img_req = obj_req->img_request;
2371
2372	switch (img_req->op_type) {
2373	case OBJ_OP_WRITE:
2374		if (!use_object_map(img_req->rbd_dev) ||
2375		    !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST))
2376			return 2; /* setallochint + write/writefull */
2377
2378		return 1; /* write/writefull */
2379	case OBJ_OP_DISCARD:
2380		return 1; /* delete/truncate/zero */
2381	case OBJ_OP_ZEROOUT:
2382		if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents &&
2383		    !(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2384			return 2; /* create + truncate */
2385
2386		return 1; /* delete/truncate/zero */
2387	default:
2388		BUG();
2389	}
2390}
2391
2392static void rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2393				    int which)
2394{
2395	struct rbd_obj_request *obj_req = osd_req->r_priv;
2396
2397	switch (obj_req->img_request->op_type) {
2398	case OBJ_OP_WRITE:
2399		__rbd_osd_setup_write_ops(osd_req, which);
2400		break;
2401	case OBJ_OP_DISCARD:
2402		__rbd_osd_setup_discard_ops(osd_req, which);
2403		break;
2404	case OBJ_OP_ZEROOUT:
2405		__rbd_osd_setup_zeroout_ops(osd_req, which);
2406		break;
2407	default:
2408		BUG();
2409	}
2410}
2411
2412/*
2413 * Prune the list of object requests (adjust offset and/or length, drop
2414 * redundant requests).  Prepare object request state machines and image
2415 * request state machine for execution.
2416 */
2417static int __rbd_img_fill_request(struct rbd_img_request *img_req)
2418{
2419	struct rbd_obj_request *obj_req, *next_obj_req;
 
 
 
 
 
 
 
 
 
 
2420	int ret;
 
 
2421
2422	for_each_obj_request_safe(img_req, obj_req, next_obj_req) {
2423		switch (img_req->op_type) {
2424		case OBJ_OP_READ:
2425			ret = rbd_obj_init_read(obj_req);
2426			break;
2427		case OBJ_OP_WRITE:
2428			ret = rbd_obj_init_write(obj_req);
2429			break;
2430		case OBJ_OP_DISCARD:
2431			ret = rbd_obj_init_discard(obj_req);
2432			break;
2433		case OBJ_OP_ZEROOUT:
2434			ret = rbd_obj_init_zeroout(obj_req);
2435			break;
2436		default:
2437			BUG();
2438		}
2439		if (ret < 0)
2440			return ret;
2441		if (ret > 0) {
2442			rbd_img_obj_request_del(img_req, obj_req);
2443			continue;
2444		}
2445	}
2446
2447	img_req->state = RBD_IMG_START;
2448	return 0;
2449}
 
2450
2451union rbd_img_fill_iter {
2452	struct ceph_bio_iter	bio_iter;
2453	struct ceph_bvec_iter	bvec_iter;
2454};
2455
2456struct rbd_img_fill_ctx {
2457	enum obj_request_type	pos_type;
2458	union rbd_img_fill_iter	*pos;
2459	union rbd_img_fill_iter	iter;
2460	ceph_object_extent_fn_t	set_pos_fn;
2461	ceph_object_extent_fn_t	count_fn;
2462	ceph_object_extent_fn_t	copy_fn;
2463};
2464
2465static struct ceph_object_extent *alloc_object_extent(void *arg)
2466{
2467	struct rbd_img_request *img_req = arg;
2468	struct rbd_obj_request *obj_req;
2469
2470	obj_req = rbd_obj_request_create();
2471	if (!obj_req)
2472		return NULL;
 
 
 
 
 
 
2473
2474	rbd_img_obj_request_add(img_req, obj_req);
2475	return &obj_req->ex;
 
 
2476}
2477
2478/*
2479 * While su != os && sc == 1 is technically not fancy (it's the same
2480 * layout as su == os && sc == 1), we can't use the nocopy path for it
2481 * because ->set_pos_fn() should be called only once per object.
2482 * ceph_file_to_extents() invokes action_fn once per stripe unit, so
2483 * treat su != os && sc == 1 as fancy.
2484 */
2485static bool rbd_layout_is_fancy(struct ceph_file_layout *l)
 
 
 
 
 
 
2486{
2487	return l->stripe_unit != l->object_size;
2488}
2489
2490static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req,
2491				       struct ceph_file_extent *img_extents,
2492				       u32 num_img_extents,
2493				       struct rbd_img_fill_ctx *fctx)
2494{
2495	u32 i;
2496	int ret;
2497
2498	img_req->data_type = fctx->pos_type;
2499
2500	/*
2501	 * Create object requests and set each object request's starting
2502	 * position in the provided bio (list) or bio_vec array.
2503	 */
2504	fctx->iter = *fctx->pos;
2505	for (i = 0; i < num_img_extents; i++) {
2506		ret = ceph_file_to_extents(&img_req->rbd_dev->layout,
2507					   img_extents[i].fe_off,
2508					   img_extents[i].fe_len,
2509					   &img_req->object_extents,
2510					   alloc_object_extent, img_req,
2511					   fctx->set_pos_fn, &fctx->iter);
2512		if (ret)
2513			return ret;
2514	}
2515
2516	return __rbd_img_fill_request(img_req);
2517}
2518
2519/*
2520 * Map a list of image extents to a list of object extents, create the
2521 * corresponding object requests (normally each to a different object,
2522 * but not always) and add them to @img_req.  For each object request,
2523 * set up its data descriptor to point to the corresponding chunk(s) of
2524 * @fctx->pos data buffer.
2525 *
2526 * Because ceph_file_to_extents() will merge adjacent object extents
2527 * together, each object request's data descriptor may point to multiple
2528 * different chunks of @fctx->pos data buffer.
2529 *
2530 * @fctx->pos data buffer is assumed to be large enough.
2531 */
2532static int rbd_img_fill_request(struct rbd_img_request *img_req,
2533				struct ceph_file_extent *img_extents,
2534				u32 num_img_extents,
2535				struct rbd_img_fill_ctx *fctx)
2536{
2537	struct rbd_device *rbd_dev = img_req->rbd_dev;
2538	struct rbd_obj_request *obj_req;
2539	u32 i;
2540	int ret;
2541
2542	if (fctx->pos_type == OBJ_REQUEST_NODATA ||
2543	    !rbd_layout_is_fancy(&rbd_dev->layout))
2544		return rbd_img_fill_request_nocopy(img_req, img_extents,
2545						   num_img_extents, fctx);
2546
2547	img_req->data_type = OBJ_REQUEST_OWN_BVECS;
2548
2549	/*
2550	 * Create object requests and determine ->bvec_count for each object
2551	 * request.  Note that ->bvec_count sum over all object requests may
2552	 * be greater than the number of bio_vecs in the provided bio (list)
2553	 * or bio_vec array because when mapped, those bio_vecs can straddle
2554	 * stripe unit boundaries.
2555	 */
2556	fctx->iter = *fctx->pos;
2557	for (i = 0; i < num_img_extents; i++) {
2558		ret = ceph_file_to_extents(&rbd_dev->layout,
2559					   img_extents[i].fe_off,
2560					   img_extents[i].fe_len,
2561					   &img_req->object_extents,
2562					   alloc_object_extent, img_req,
2563					   fctx->count_fn, &fctx->iter);
2564		if (ret)
2565			return ret;
2566	}
2567
2568	for_each_obj_request(img_req, obj_req) {
2569		obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count,
2570					      sizeof(*obj_req->bvec_pos.bvecs),
2571					      GFP_NOIO);
2572		if (!obj_req->bvec_pos.bvecs)
2573			return -ENOMEM;
2574	}
2575
2576	/*
2577	 * Fill in each object request's private bio_vec array, splitting and
2578	 * rearranging the provided bio_vecs in stripe unit chunks as needed.
2579	 */
2580	fctx->iter = *fctx->pos;
2581	for (i = 0; i < num_img_extents; i++) {
2582		ret = ceph_iterate_extents(&rbd_dev->layout,
2583					   img_extents[i].fe_off,
2584					   img_extents[i].fe_len,
2585					   &img_req->object_extents,
2586					   fctx->copy_fn, &fctx->iter);
2587		if (ret)
2588			return ret;
2589	}
2590
2591	return __rbd_img_fill_request(img_req);
2592}
2593
2594static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
2595			       u64 off, u64 len)
2596{
2597	struct ceph_file_extent ex = { off, len };
2598	union rbd_img_fill_iter dummy = {};
2599	struct rbd_img_fill_ctx fctx = {
2600		.pos_type = OBJ_REQUEST_NODATA,
2601		.pos = &dummy,
2602	};
2603
2604	return rbd_img_fill_request(img_req, &ex, 1, &fctx);
2605}
2606
2607static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2608{
2609	struct rbd_obj_request *obj_req =
2610	    container_of(ex, struct rbd_obj_request, ex);
2611	struct ceph_bio_iter *it = arg;
2612
2613	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2614	obj_req->bio_pos = *it;
2615	ceph_bio_iter_advance(it, bytes);
2616}
2617
2618static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2619{
2620	struct rbd_obj_request *obj_req =
2621	    container_of(ex, struct rbd_obj_request, ex);
2622	struct ceph_bio_iter *it = arg;
2623
2624	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2625	ceph_bio_iter_advance_step(it, bytes, ({
2626		obj_req->bvec_count++;
2627	}));
2628
2629}
2630
2631static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2632{
2633	struct rbd_obj_request *obj_req =
2634	    container_of(ex, struct rbd_obj_request, ex);
2635	struct ceph_bio_iter *it = arg;
2636
2637	dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2638	ceph_bio_iter_advance_step(it, bytes, ({
2639		obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2640		obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2641	}));
2642}
2643
2644static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2645				   struct ceph_file_extent *img_extents,
2646				   u32 num_img_extents,
2647				   struct ceph_bio_iter *bio_pos)
2648{
2649	struct rbd_img_fill_ctx fctx = {
2650		.pos_type = OBJ_REQUEST_BIO,
2651		.pos = (union rbd_img_fill_iter *)bio_pos,
2652		.set_pos_fn = set_bio_pos,
2653		.count_fn = count_bio_bvecs,
2654		.copy_fn = copy_bio_bvecs,
2655	};
2656
2657	return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2658				    &fctx);
2659}
2660
2661static int rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2662				 u64 off, u64 len, struct bio *bio)
2663{
2664	struct ceph_file_extent ex = { off, len };
2665	struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter };
2666
2667	return __rbd_img_fill_from_bio(img_req, &ex, 1, &it);
2668}
2669
2670static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2671{
2672	struct rbd_obj_request *obj_req =
2673	    container_of(ex, struct rbd_obj_request, ex);
2674	struct ceph_bvec_iter *it = arg;
2675
2676	obj_req->bvec_pos = *it;
2677	ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes);
2678	ceph_bvec_iter_advance(it, bytes);
2679}
2680
2681static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2682{
2683	struct rbd_obj_request *obj_req =
2684	    container_of(ex, struct rbd_obj_request, ex);
2685	struct ceph_bvec_iter *it = arg;
2686
2687	ceph_bvec_iter_advance_step(it, bytes, ({
2688		obj_req->bvec_count++;
2689	}));
2690}
2691
2692static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2693{
2694	struct rbd_obj_request *obj_req =
2695	    container_of(ex, struct rbd_obj_request, ex);
2696	struct ceph_bvec_iter *it = arg;
2697
2698	ceph_bvec_iter_advance_step(it, bytes, ({
2699		obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2700		obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2701	}));
2702}
2703
2704static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2705				     struct ceph_file_extent *img_extents,
2706				     u32 num_img_extents,
2707				     struct ceph_bvec_iter *bvec_pos)
2708{
2709	struct rbd_img_fill_ctx fctx = {
2710		.pos_type = OBJ_REQUEST_BVECS,
2711		.pos = (union rbd_img_fill_iter *)bvec_pos,
2712		.set_pos_fn = set_bvec_pos,
2713		.count_fn = count_bvecs,
2714		.copy_fn = copy_bvecs,
2715	};
2716
2717	return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2718				    &fctx);
2719}
2720
2721static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2722				   struct ceph_file_extent *img_extents,
2723				   u32 num_img_extents,
2724				   struct bio_vec *bvecs)
2725{
2726	struct ceph_bvec_iter it = {
2727		.bvecs = bvecs,
2728		.iter = { .bi_size = ceph_file_extents_bytes(img_extents,
2729							     num_img_extents) },
2730	};
2731
2732	return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents,
2733					 &it);
2734}
2735
2736static void rbd_img_handle_request_work(struct work_struct *work)
2737{
2738	struct rbd_img_request *img_req =
2739	    container_of(work, struct rbd_img_request, work);
2740
2741	rbd_img_handle_request(img_req, img_req->work_result);
2742}
2743
2744static void rbd_img_schedule(struct rbd_img_request *img_req, int result)
2745{
2746	INIT_WORK(&img_req->work, rbd_img_handle_request_work);
2747	img_req->work_result = result;
2748	queue_work(rbd_wq, &img_req->work);
2749}
2750
2751static bool rbd_obj_may_exist(struct rbd_obj_request *obj_req)
2752{
2753	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2754
2755	if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno)) {
2756		obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2757		return true;
2758	}
2759
2760	dout("%s %p objno %llu assuming dne\n", __func__, obj_req,
2761	     obj_req->ex.oe_objno);
2762	return false;
2763}
2764
2765static int rbd_obj_read_object(struct rbd_obj_request *obj_req)
2766{
2767	struct ceph_osd_request *osd_req;
2768	int ret;
2769
2770	osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1);
2771	if (IS_ERR(osd_req))
2772		return PTR_ERR(osd_req);
2773
2774	osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ,
2775			       obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2776	rbd_osd_setup_data(osd_req, 0);
2777	rbd_osd_format_read(osd_req);
2778
2779	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2780	if (ret)
2781		return ret;
2782
2783	rbd_osd_submit(osd_req);
2784	return 0;
2785}
2786
2787static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
2788{
2789	struct rbd_img_request *img_req = obj_req->img_request;
2790	struct rbd_device *parent = img_req->rbd_dev->parent;
2791	struct rbd_img_request *child_img_req;
2792	int ret;
2793
2794	child_img_req = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
2795	if (!child_img_req)
2796		return -ENOMEM;
2797
2798	rbd_img_request_init(child_img_req, parent, OBJ_OP_READ);
2799	__set_bit(IMG_REQ_CHILD, &child_img_req->flags);
2800	child_img_req->obj_request = obj_req;
2801
2802	down_read(&parent->header_rwsem);
2803	rbd_img_capture_header(child_img_req);
2804	up_read(&parent->header_rwsem);
2805
2806	dout("%s child_img_req %p for obj_req %p\n", __func__, child_img_req,
2807	     obj_req);
2808
2809	if (!rbd_img_is_write(img_req)) {
2810		switch (img_req->data_type) {
2811		case OBJ_REQUEST_BIO:
2812			ret = __rbd_img_fill_from_bio(child_img_req,
2813						      obj_req->img_extents,
2814						      obj_req->num_img_extents,
2815						      &obj_req->bio_pos);
2816			break;
2817		case OBJ_REQUEST_BVECS:
2818		case OBJ_REQUEST_OWN_BVECS:
2819			ret = __rbd_img_fill_from_bvecs(child_img_req,
2820						      obj_req->img_extents,
2821						      obj_req->num_img_extents,
2822						      &obj_req->bvec_pos);
2823			break;
2824		default:
2825			BUG();
2826		}
2827	} else {
2828		ret = rbd_img_fill_from_bvecs(child_img_req,
2829					      obj_req->img_extents,
2830					      obj_req->num_img_extents,
2831					      obj_req->copyup_bvecs);
2832	}
2833	if (ret) {
2834		rbd_img_request_destroy(child_img_req);
2835		return ret;
2836	}
2837
2838	/* avoid parent chain recursion */
2839	rbd_img_schedule(child_img_req, 0);
2840	return 0;
2841}
2842
2843static bool rbd_obj_advance_read(struct rbd_obj_request *obj_req, int *result)
2844{
2845	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2846	int ret;
2847
2848again:
2849	switch (obj_req->read_state) {
2850	case RBD_OBJ_READ_START:
2851		rbd_assert(!*result);
2852
2853		if (!rbd_obj_may_exist(obj_req)) {
2854			*result = -ENOENT;
2855			obj_req->read_state = RBD_OBJ_READ_OBJECT;
2856			goto again;
2857		}
2858
2859		ret = rbd_obj_read_object(obj_req);
2860		if (ret) {
2861			*result = ret;
2862			return true;
2863		}
2864		obj_req->read_state = RBD_OBJ_READ_OBJECT;
2865		return false;
2866	case RBD_OBJ_READ_OBJECT:
2867		if (*result == -ENOENT && rbd_dev->parent_overlap) {
2868			/* reverse map this object extent onto the parent */
2869			ret = rbd_obj_calc_img_extents(obj_req, false);
2870			if (ret) {
2871				*result = ret;
2872				return true;
2873			}
2874			if (obj_req->num_img_extents) {
2875				ret = rbd_obj_read_from_parent(obj_req);
2876				if (ret) {
2877					*result = ret;
2878					return true;
2879				}
2880				obj_req->read_state = RBD_OBJ_READ_PARENT;
2881				return false;
2882			}
2883		}
2884
2885		/*
2886		 * -ENOENT means a hole in the image -- zero-fill the entire
2887		 * length of the request.  A short read also implies zero-fill
2888		 * to the end of the request.
2889		 */
2890		if (*result == -ENOENT) {
2891			rbd_obj_zero_range(obj_req, 0, obj_req->ex.oe_len);
2892			*result = 0;
2893		} else if (*result >= 0) {
2894			if (*result < obj_req->ex.oe_len)
2895				rbd_obj_zero_range(obj_req, *result,
2896						obj_req->ex.oe_len - *result);
2897			else
2898				rbd_assert(*result == obj_req->ex.oe_len);
2899			*result = 0;
2900		}
2901		return true;
2902	case RBD_OBJ_READ_PARENT:
2903		/*
2904		 * The parent image is read only up to the overlap -- zero-fill
2905		 * from the overlap to the end of the request.
2906		 */
2907		if (!*result) {
2908			u32 obj_overlap = rbd_obj_img_extents_bytes(obj_req);
2909
2910			if (obj_overlap < obj_req->ex.oe_len)
2911				rbd_obj_zero_range(obj_req, obj_overlap,
2912					    obj_req->ex.oe_len - obj_overlap);
2913		}
2914		return true;
2915	default:
2916		BUG();
2917	}
2918}
2919
2920static bool rbd_obj_write_is_noop(struct rbd_obj_request *obj_req)
2921{
2922	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2923
2924	if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno))
2925		obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2926
2927	if (!(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST) &&
2928	    (obj_req->flags & RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT)) {
2929		dout("%s %p noop for nonexistent\n", __func__, obj_req);
2930		return true;
2931	}
2932
2933	return false;
2934}
2935
2936/*
2937 * Return:
2938 *   0 - object map update sent
2939 *   1 - object map update isn't needed
2940 *  <0 - error
2941 */
2942static int rbd_obj_write_pre_object_map(struct rbd_obj_request *obj_req)
 
 
 
 
 
 
2943{
2944	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2945	u8 new_state;
2946
2947	if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
2948		return 1;
2949
2950	if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
2951		new_state = OBJECT_PENDING;
2952	else
2953		new_state = OBJECT_EXISTS;
2954
2955	return rbd_object_map_update(obj_req, CEPH_NOSNAP, new_state, NULL);
2956}
2957
2958static int rbd_obj_write_object(struct rbd_obj_request *obj_req)
2959{
2960	struct ceph_osd_request *osd_req;
2961	int num_ops = count_write_ops(obj_req);
2962	int which = 0;
2963	int ret;
2964
2965	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
2966		num_ops++; /* stat */
2967
2968	osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
2969	if (IS_ERR(osd_req))
2970		return PTR_ERR(osd_req);
2971
2972	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
2973		ret = rbd_osd_setup_stat(osd_req, which++);
2974		if (ret)
2975			return ret;
2976	}
2977
2978	rbd_osd_setup_write_ops(osd_req, which);
2979	rbd_osd_format_write(osd_req);
2980
2981	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2982	if (ret)
2983		return ret;
2984
2985	rbd_osd_submit(osd_req);
2986	return 0;
2987}
2988
2989/*
2990 * copyup_bvecs pages are never highmem pages
2991 */
2992static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes)
2993{
2994	struct ceph_bvec_iter it = {
2995		.bvecs = bvecs,
2996		.iter = { .bi_size = bytes },
2997	};
2998
2999	ceph_bvec_iter_advance_step(&it, bytes, ({
3000		if (memchr_inv(page_address(bv.bv_page) + bv.bv_offset, 0,
3001			       bv.bv_len))
3002			return false;
3003	}));
3004	return true;
3005}
3006
3007#define MODS_ONLY	U32_MAX
3008
3009static int rbd_obj_copyup_empty_snapc(struct rbd_obj_request *obj_req,
3010				      u32 bytes)
3011{
3012	struct ceph_osd_request *osd_req;
3013	int ret;
3014
3015	dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3016	rbd_assert(bytes > 0 && bytes != MODS_ONLY);
3017
3018	osd_req = __rbd_obj_add_osd_request(obj_req, &rbd_empty_snapc, 1);
3019	if (IS_ERR(osd_req))
3020		return PTR_ERR(osd_req);
3021
3022	ret = rbd_osd_setup_copyup(osd_req, 0, bytes);
3023	if (ret)
3024		return ret;
3025
3026	rbd_osd_format_write(osd_req);
3027
3028	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3029	if (ret)
3030		return ret;
3031
3032	rbd_osd_submit(osd_req);
3033	return 0;
3034}
3035
3036static int rbd_obj_copyup_current_snapc(struct rbd_obj_request *obj_req,
3037					u32 bytes)
3038{
3039	struct ceph_osd_request *osd_req;
3040	int num_ops = count_write_ops(obj_req);
3041	int which = 0;
3042	int ret;
3043
3044	dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3045
3046	if (bytes != MODS_ONLY)
3047		num_ops++; /* copyup */
3048
3049	osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
3050	if (IS_ERR(osd_req))
3051		return PTR_ERR(osd_req);
3052
3053	if (bytes != MODS_ONLY) {
3054		ret = rbd_osd_setup_copyup(osd_req, which++, bytes);
3055		if (ret)
3056			return ret;
3057	}
3058
3059	rbd_osd_setup_write_ops(osd_req, which);
3060	rbd_osd_format_write(osd_req);
3061
3062	ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3063	if (ret)
3064		return ret;
3065
3066	rbd_osd_submit(osd_req);
3067	return 0;
3068}
3069
3070static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap)
3071{
3072	u32 i;
3073
3074	rbd_assert(!obj_req->copyup_bvecs);
3075	obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap);
3076	obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count,
3077					sizeof(*obj_req->copyup_bvecs),
3078					GFP_NOIO);
3079	if (!obj_req->copyup_bvecs)
3080		return -ENOMEM;
3081
3082	for (i = 0; i < obj_req->copyup_bvec_count; i++) {
3083		unsigned int len = min(obj_overlap, (u64)PAGE_SIZE);
3084
3085		obj_req->copyup_bvecs[i].bv_page = alloc_page(GFP_NOIO);
3086		if (!obj_req->copyup_bvecs[i].bv_page)
3087			return -ENOMEM;
3088
3089		obj_req->copyup_bvecs[i].bv_offset = 0;
3090		obj_req->copyup_bvecs[i].bv_len = len;
3091		obj_overlap -= len;
3092	}
3093
3094	rbd_assert(!obj_overlap);
3095	return 0;
3096}
3097
3098/*
3099 * The target object doesn't exist.  Read the data for the entire
3100 * target object up to the overlap point (if any) from the parent,
3101 * so we can use it for a copyup.
3102 */
3103static int rbd_obj_copyup_read_parent(struct rbd_obj_request *obj_req)
 
 
 
3104{
3105	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
 
3106	int ret;
3107
3108	rbd_assert(obj_req->num_img_extents);
3109	prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
3110		      rbd_dev->parent_overlap);
3111	if (!obj_req->num_img_extents) {
3112		/*
3113		 * The overlap has become 0 (most likely because the
3114		 * image has been flattened).  Re-submit the original write
3115		 * request -- pass MODS_ONLY since the copyup isn't needed
3116		 * anymore.
3117		 */
3118		return rbd_obj_copyup_current_snapc(obj_req, MODS_ONLY);
3119	}
3120
3121	ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req));
3122	if (ret)
3123		return ret;
3124
3125	return rbd_obj_read_from_parent(obj_req);
3126}
 
3127
3128static void rbd_obj_copyup_object_maps(struct rbd_obj_request *obj_req)
3129{
3130	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3131	struct ceph_snap_context *snapc = obj_req->img_request->snapc;
3132	u8 new_state;
3133	u32 i;
3134	int ret;
 
3135
3136	rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3137
3138	if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3139		return;
3140
3141	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3142		return;
3143
3144	for (i = 0; i < snapc->num_snaps; i++) {
3145		if ((rbd_dev->header.features & RBD_FEATURE_FAST_DIFF) &&
3146		    i + 1 < snapc->num_snaps)
3147			new_state = OBJECT_EXISTS_CLEAN;
3148		else
3149			new_state = OBJECT_EXISTS;
3150
3151		ret = rbd_object_map_update(obj_req, snapc->snaps[i],
3152					    new_state, NULL);
3153		if (ret < 0) {
3154			obj_req->pending.result = ret;
3155			return;
3156		}
3157
3158		rbd_assert(!ret);
3159		obj_req->pending.num_pending++;
3160	}
3161}
3162
3163static void rbd_obj_copyup_write_object(struct rbd_obj_request *obj_req)
3164{
3165	u32 bytes = rbd_obj_img_extents_bytes(obj_req);
3166	int ret;
3167
3168	rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3169
3170	/*
3171	 * Only send non-zero copyup data to save some I/O and network
3172	 * bandwidth -- zero copyup data is equivalent to the object not
3173	 * existing.
3174	 */
3175	if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3176		bytes = 0;
3177
3178	if (obj_req->img_request->snapc->num_snaps && bytes > 0) {
3179		/*
3180		 * Send a copyup request with an empty snapshot context to
3181		 * deep-copyup the object through all existing snapshots.
3182		 * A second request with the current snapshot context will be
3183		 * sent for the actual modification.
3184		 */
3185		ret = rbd_obj_copyup_empty_snapc(obj_req, bytes);
3186		if (ret) {
3187			obj_req->pending.result = ret;
3188			return;
3189		}
3190
3191		obj_req->pending.num_pending++;
3192		bytes = MODS_ONLY;
3193	}
3194
3195	ret = rbd_obj_copyup_current_snapc(obj_req, bytes);
3196	if (ret) {
3197		obj_req->pending.result = ret;
3198		return;
3199	}
3200
3201	obj_req->pending.num_pending++;
3202}
3203
3204static bool rbd_obj_advance_copyup(struct rbd_obj_request *obj_req, int *result)
3205{
3206	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3207	int ret;
3208
3209again:
3210	switch (obj_req->copyup_state) {
3211	case RBD_OBJ_COPYUP_START:
3212		rbd_assert(!*result);
3213
3214		ret = rbd_obj_copyup_read_parent(obj_req);
3215		if (ret) {
3216			*result = ret;
3217			return true;
3218		}
3219		if (obj_req->num_img_extents)
3220			obj_req->copyup_state = RBD_OBJ_COPYUP_READ_PARENT;
3221		else
3222			obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3223		return false;
3224	case RBD_OBJ_COPYUP_READ_PARENT:
3225		if (*result)
3226			return true;
3227
3228		if (is_zero_bvecs(obj_req->copyup_bvecs,
3229				  rbd_obj_img_extents_bytes(obj_req))) {
3230			dout("%s %p detected zeros\n", __func__, obj_req);
3231			obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ZEROS;
3232		}
3233
3234		rbd_obj_copyup_object_maps(obj_req);
3235		if (!obj_req->pending.num_pending) {
3236			*result = obj_req->pending.result;
3237			obj_req->copyup_state = RBD_OBJ_COPYUP_OBJECT_MAPS;
3238			goto again;
3239		}
3240		obj_req->copyup_state = __RBD_OBJ_COPYUP_OBJECT_MAPS;
3241		return false;
3242	case __RBD_OBJ_COPYUP_OBJECT_MAPS:
3243		if (!pending_result_dec(&obj_req->pending, result))
3244			return false;
3245		fallthrough;
3246	case RBD_OBJ_COPYUP_OBJECT_MAPS:
3247		if (*result) {
3248			rbd_warn(rbd_dev, "snap object map update failed: %d",
3249				 *result);
3250			return true;
3251		}
3252
3253		rbd_obj_copyup_write_object(obj_req);
3254		if (!obj_req->pending.num_pending) {
3255			*result = obj_req->pending.result;
3256			obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3257			goto again;
3258		}
3259		obj_req->copyup_state = __RBD_OBJ_COPYUP_WRITE_OBJECT;
3260		return false;
3261	case __RBD_OBJ_COPYUP_WRITE_OBJECT:
3262		if (!pending_result_dec(&obj_req->pending, result))
3263			return false;
3264		fallthrough;
3265	case RBD_OBJ_COPYUP_WRITE_OBJECT:
3266		return true;
3267	default:
3268		BUG();
3269	}
3270}
3271
3272/*
3273 * Return:
3274 *   0 - object map update sent
3275 *   1 - object map update isn't needed
3276 *  <0 - error
3277 */
3278static int rbd_obj_write_post_object_map(struct rbd_obj_request *obj_req)
 
 
3279{
3280	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3281	u8 current_state = OBJECT_PENDING;
3282
3283	if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3284		return 1;
 
3285
3286	if (!(obj_req->flags & RBD_OBJ_FLAG_DELETION))
3287		return 1;
 
 
3288
3289	return rbd_object_map_update(obj_req, CEPH_NOSNAP, OBJECT_NONEXISTENT,
3290				     &current_state);
3291}
 
 
 
 
 
 
 
 
3292
3293static bool rbd_obj_advance_write(struct rbd_obj_request *obj_req, int *result)
3294{
3295	struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3296	int ret;
3297
3298again:
3299	switch (obj_req->write_state) {
3300	case RBD_OBJ_WRITE_START:
3301		rbd_assert(!*result);
3302
3303		if (rbd_obj_write_is_noop(obj_req))
3304			return true;
3305
3306		ret = rbd_obj_write_pre_object_map(obj_req);
3307		if (ret < 0) {
3308			*result = ret;
3309			return true;
3310		}
3311		obj_req->write_state = RBD_OBJ_WRITE_PRE_OBJECT_MAP;
3312		if (ret > 0)
3313			goto again;
3314		return false;
3315	case RBD_OBJ_WRITE_PRE_OBJECT_MAP:
3316		if (*result) {
3317			rbd_warn(rbd_dev, "pre object map update failed: %d",
3318				 *result);
3319			return true;
3320		}
3321		ret = rbd_obj_write_object(obj_req);
3322		if (ret) {
3323			*result = ret;
3324			return true;
3325		}
3326		obj_req->write_state = RBD_OBJ_WRITE_OBJECT;
3327		return false;
3328	case RBD_OBJ_WRITE_OBJECT:
3329		if (*result == -ENOENT) {
3330			if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
3331				*result = 0;
3332				obj_req->copyup_state = RBD_OBJ_COPYUP_START;
3333				obj_req->write_state = __RBD_OBJ_WRITE_COPYUP;
3334				goto again;
3335			}
3336			/*
3337			 * On a non-existent object:
3338			 *   delete - -ENOENT, truncate/zero - 0
3339			 */
3340			if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
3341				*result = 0;
3342		}
3343		if (*result)
3344			return true;
3345
3346		obj_req->write_state = RBD_OBJ_WRITE_COPYUP;
3347		goto again;
3348	case __RBD_OBJ_WRITE_COPYUP:
3349		if (!rbd_obj_advance_copyup(obj_req, result))
3350			return false;
3351		fallthrough;
3352	case RBD_OBJ_WRITE_COPYUP:
3353		if (*result) {
3354			rbd_warn(rbd_dev, "copyup failed: %d", *result);
3355			return true;
3356		}
3357		ret = rbd_obj_write_post_object_map(obj_req);
3358		if (ret < 0) {
3359			*result = ret;
3360			return true;
3361		}
3362		obj_req->write_state = RBD_OBJ_WRITE_POST_OBJECT_MAP;
3363		if (ret > 0)
3364			goto again;
3365		return false;
3366	case RBD_OBJ_WRITE_POST_OBJECT_MAP:
3367		if (*result)
3368			rbd_warn(rbd_dev, "post object map update failed: %d",
3369				 *result);
3370		return true;
3371	default:
3372		BUG();
3373	}
3374}
3375
3376/*
3377 * Return true if @obj_req is completed.
3378 */
3379static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req,
3380				     int *result)
3381{
3382	struct rbd_img_request *img_req = obj_req->img_request;
3383	struct rbd_device *rbd_dev = img_req->rbd_dev;
3384	bool done;
3385
3386	mutex_lock(&obj_req->state_mutex);
3387	if (!rbd_img_is_write(img_req))
3388		done = rbd_obj_advance_read(obj_req, result);
3389	else
3390		done = rbd_obj_advance_write(obj_req, result);
3391	mutex_unlock(&obj_req->state_mutex);
3392
3393	if (done && *result) {
3394		rbd_assert(*result < 0);
3395		rbd_warn(rbd_dev, "%s at objno %llu %llu~%llu result %d",
3396			 obj_op_name(img_req->op_type), obj_req->ex.oe_objno,
3397			 obj_req->ex.oe_off, obj_req->ex.oe_len, *result);
3398	}
3399	return done;
3400}
3401
3402/*
3403 * This is open-coded in rbd_img_handle_request() to avoid parent chain
3404 * recursion.
3405 */
3406static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result)
3407{
3408	if (__rbd_obj_handle_request(obj_req, &result))
3409		rbd_img_handle_request(obj_req->img_request, result);
3410}
3411
3412static bool need_exclusive_lock(struct rbd_img_request *img_req)
3413{
3414	struct rbd_device *rbd_dev = img_req->rbd_dev;
3415
3416	if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK))
3417		return false;
 
 
 
 
3418
3419	if (rbd_is_ro(rbd_dev))
3420		return false;
3421
3422	rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags));
3423	if (rbd_dev->opts->lock_on_read ||
3424	    (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3425		return true;
3426
3427	return rbd_img_is_write(img_req);
3428}
3429
3430static bool rbd_lock_add_request(struct rbd_img_request *img_req)
3431{
3432	struct rbd_device *rbd_dev = img_req->rbd_dev;
3433	bool locked;
3434
3435	lockdep_assert_held(&rbd_dev->lock_rwsem);
3436	locked = rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED;
3437	spin_lock(&rbd_dev->lock_lists_lock);
3438	rbd_assert(list_empty(&img_req->lock_item));
3439	if (!locked)
3440		list_add_tail(&img_req->lock_item, &rbd_dev->acquiring_list);
3441	else
3442		list_add_tail(&img_req->lock_item, &rbd_dev->running_list);
3443	spin_unlock(&rbd_dev->lock_lists_lock);
3444	return locked;
3445}
3446
3447static void rbd_lock_del_request(struct rbd_img_request *img_req)
3448{
3449	struct rbd_device *rbd_dev = img_req->rbd_dev;
3450	bool need_wakeup;
3451
3452	lockdep_assert_held(&rbd_dev->lock_rwsem);
3453	spin_lock(&rbd_dev->lock_lists_lock);
3454	rbd_assert(!list_empty(&img_req->lock_item));
3455	list_del_init(&img_req->lock_item);
3456	need_wakeup = (rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING &&
3457		       list_empty(&rbd_dev->running_list));
3458	spin_unlock(&rbd_dev->lock_lists_lock);
3459	if (need_wakeup)
3460		complete(&rbd_dev->releasing_wait);
3461}
3462
3463static int rbd_img_exclusive_lock(struct rbd_img_request *img_req)
3464{
3465	struct rbd_device *rbd_dev = img_req->rbd_dev;
3466
3467	if (!need_exclusive_lock(img_req))
3468		return 1;
3469
3470	if (rbd_lock_add_request(img_req))
3471		return 1;
3472
3473	if (rbd_dev->opts->exclusive) {
3474		WARN_ON(1); /* lock got released? */
3475		return -EROFS;
3476	}
3477
3478	/*
3479	 * Note the use of mod_delayed_work() in rbd_acquire_lock()
3480	 * and cancel_delayed_work() in wake_lock_waiters().
3481	 */
3482	dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev);
3483	queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
3484	return 0;
3485}
3486
3487static void rbd_img_object_requests(struct rbd_img_request *img_req)
3488{
3489	struct rbd_obj_request *obj_req;
3490
3491	rbd_assert(!img_req->pending.result && !img_req->pending.num_pending);
3492
3493	for_each_obj_request(img_req, obj_req) {
3494		int result = 0;
3495
3496		if (__rbd_obj_handle_request(obj_req, &result)) {
3497			if (result) {
3498				img_req->pending.result = result;
3499				return;
3500			}
3501		} else {
3502			img_req->pending.num_pending++;
3503		}
3504	}
3505}
3506
3507static bool rbd_img_advance(struct rbd_img_request *img_req, int *result)
3508{
3509	struct rbd_device *rbd_dev = img_req->rbd_dev;
3510	int ret;
3511
3512again:
3513	switch (img_req->state) {
3514	case RBD_IMG_START:
3515		rbd_assert(!*result);
3516
3517		ret = rbd_img_exclusive_lock(img_req);
3518		if (ret < 0) {
3519			*result = ret;
3520			return true;
3521		}
3522		img_req->state = RBD_IMG_EXCLUSIVE_LOCK;
3523		if (ret > 0)
3524			goto again;
3525		return false;
3526	case RBD_IMG_EXCLUSIVE_LOCK:
3527		if (*result)
3528			return true;
3529
3530		rbd_assert(!need_exclusive_lock(img_req) ||
3531			   __rbd_is_lock_owner(rbd_dev));
3532
3533		rbd_img_object_requests(img_req);
3534		if (!img_req->pending.num_pending) {
3535			*result = img_req->pending.result;
3536			img_req->state = RBD_IMG_OBJECT_REQUESTS;
3537			goto again;
3538		}
3539		img_req->state = __RBD_IMG_OBJECT_REQUESTS;
3540		return false;
3541	case __RBD_IMG_OBJECT_REQUESTS:
3542		if (!pending_result_dec(&img_req->pending, result))
3543			return false;
3544		fallthrough;
3545	case RBD_IMG_OBJECT_REQUESTS:
3546		return true;
3547	default:
3548		BUG();
3549	}
3550}
3551
3552/*
3553 * Return true if @img_req is completed.
3554 */
3555static bool __rbd_img_handle_request(struct rbd_img_request *img_req,
3556				     int *result)
3557{
3558	struct rbd_device *rbd_dev = img_req->rbd_dev;
3559	bool done;
3560
3561	if (need_exclusive_lock(img_req)) {
3562		down_read(&rbd_dev->lock_rwsem);
3563		mutex_lock(&img_req->state_mutex);
3564		done = rbd_img_advance(img_req, result);
3565		if (done)
3566			rbd_lock_del_request(img_req);
3567		mutex_unlock(&img_req->state_mutex);
3568		up_read(&rbd_dev->lock_rwsem);
3569	} else {
3570		mutex_lock(&img_req->state_mutex);
3571		done = rbd_img_advance(img_req, result);
3572		mutex_unlock(&img_req->state_mutex);
3573	}
3574
3575	if (done && *result) {
3576		rbd_assert(*result < 0);
3577		rbd_warn(rbd_dev, "%s%s result %d",
3578		      test_bit(IMG_REQ_CHILD, &img_req->flags) ? "child " : "",
3579		      obj_op_name(img_req->op_type), *result);
3580	}
3581	return done;
3582}
3583
3584static void rbd_img_handle_request(struct rbd_img_request *img_req, int result)
3585{
3586again:
3587	if (!__rbd_img_handle_request(img_req, &result))
3588		return;
3589
3590	if (test_bit(IMG_REQ_CHILD, &img_req->flags)) {
3591		struct rbd_obj_request *obj_req = img_req->obj_request;
3592
3593		rbd_img_request_destroy(img_req);
3594		if (__rbd_obj_handle_request(obj_req, &result)) {
3595			img_req = obj_req->img_request;
3596			goto again;
3597		}
3598	} else {
3599		struct request *rq = blk_mq_rq_from_pdu(img_req);
3600
3601		rbd_img_request_destroy(img_req);
3602		blk_mq_end_request(rq, errno_to_blk_status(result));
3603	}
3604}
3605
3606static const struct rbd_client_id rbd_empty_cid;
3607
3608static bool rbd_cid_equal(const struct rbd_client_id *lhs,
3609			  const struct rbd_client_id *rhs)
3610{
3611	return lhs->gid == rhs->gid && lhs->handle == rhs->handle;
3612}
3613
3614static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev)
3615{
3616	struct rbd_client_id cid;
3617
3618	mutex_lock(&rbd_dev->watch_mutex);
3619	cid.gid = ceph_client_gid(rbd_dev->rbd_client->client);
3620	cid.handle = rbd_dev->watch_cookie;
3621	mutex_unlock(&rbd_dev->watch_mutex);
3622	return cid;
3623}
3624
3625/*
3626 * lock_rwsem must be held for write
3627 */
3628static void rbd_set_owner_cid(struct rbd_device *rbd_dev,
3629			      const struct rbd_client_id *cid)
3630{
3631	dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev,
3632	     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle,
3633	     cid->gid, cid->handle);
3634	rbd_dev->owner_cid = *cid; /* struct */
3635}
3636
3637static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
3638{
3639	mutex_lock(&rbd_dev->watch_mutex);
3640	sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie);
3641	mutex_unlock(&rbd_dev->watch_mutex);
3642}
3643
3644static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
3645{
3646	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3647
3648	rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
3649	strcpy(rbd_dev->lock_cookie, cookie);
3650	rbd_set_owner_cid(rbd_dev, &cid);
3651	queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
3652}
3653
3654/*
3655 * lock_rwsem must be held for write
3656 */
3657static int rbd_lock(struct rbd_device *rbd_dev)
3658{
3659	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3660	char cookie[32];
3661	int ret;
3662
3663	WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
3664		rbd_dev->lock_cookie[0] != '\0');
3665
3666	format_lock_cookie(rbd_dev, cookie);
3667	ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3668			    RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie,
3669			    RBD_LOCK_TAG, "", 0);
3670	if (ret)
3671		return ret;
3672
3673	__rbd_lock(rbd_dev, cookie);
3674	return 0;
3675}
3676
3677/*
3678 * lock_rwsem must be held for write
3679 */
3680static void rbd_unlock(struct rbd_device *rbd_dev)
3681{
3682	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3683	int ret;
3684
3685	WARN_ON(!__rbd_is_lock_owner(rbd_dev) ||
3686		rbd_dev->lock_cookie[0] == '\0');
 
 
 
 
 
 
 
 
 
 
 
 
3687
3688	ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3689			      RBD_LOCK_NAME, rbd_dev->lock_cookie);
3690	if (ret && ret != -ENOENT)
3691		rbd_warn(rbd_dev, "failed to unlock header: %d", ret);
3692
3693	/* treat errors as the image is unlocked */
3694	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
3695	rbd_dev->lock_cookie[0] = '\0';
3696	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
3697	queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work);
3698}
3699
3700static int __rbd_notify_op_lock(struct rbd_device *rbd_dev,
3701				enum rbd_notify_op notify_op,
3702				struct page ***preply_pages,
3703				size_t *preply_len)
3704{
3705	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3706	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3707	char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN];
3708	int buf_size = sizeof(buf);
3709	void *p = buf;
3710
3711	dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op);
3712
3713	/* encode *LockPayload NotifyMessage (op + ClientId) */
3714	ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN);
3715	ceph_encode_32(&p, notify_op);
3716	ceph_encode_64(&p, cid.gid);
3717	ceph_encode_64(&p, cid.handle);
3718
3719	return ceph_osdc_notify(osdc, &rbd_dev->header_oid,
3720				&rbd_dev->header_oloc, buf, buf_size,
3721				RBD_NOTIFY_TIMEOUT, preply_pages, preply_len);
3722}
3723
3724static void rbd_notify_op_lock(struct rbd_device *rbd_dev,
3725			       enum rbd_notify_op notify_op)
3726{
3727	__rbd_notify_op_lock(rbd_dev, notify_op, NULL, NULL);
3728}
3729
3730static void rbd_notify_acquired_lock(struct work_struct *work)
3731{
3732	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3733						  acquired_lock_work);
3734
3735	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK);
3736}
3737
3738static void rbd_notify_released_lock(struct work_struct *work)
3739{
3740	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3741						  released_lock_work);
3742
3743	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK);
3744}
3745
3746static int rbd_request_lock(struct rbd_device *rbd_dev)
3747{
3748	struct page **reply_pages;
3749	size_t reply_len;
3750	bool lock_owner_responded = false;
3751	int ret;
3752
3753	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3754
3755	ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK,
3756				   &reply_pages, &reply_len);
3757	if (ret && ret != -ETIMEDOUT) {
3758		rbd_warn(rbd_dev, "failed to request lock: %d", ret);
3759		goto out;
3760	}
3761
3762	if (reply_len > 0 && reply_len <= PAGE_SIZE) {
3763		void *p = page_address(reply_pages[0]);
3764		void *const end = p + reply_len;
3765		u32 n;
3766
3767		ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */
3768		while (n--) {
3769			u8 struct_v;
3770			u32 len;
3771
3772			ceph_decode_need(&p, end, 8 + 8, e_inval);
3773			p += 8 + 8; /* skip gid and cookie */
3774
3775			ceph_decode_32_safe(&p, end, len, e_inval);
3776			if (!len)
3777				continue;
3778
3779			if (lock_owner_responded) {
3780				rbd_warn(rbd_dev,
3781					 "duplicate lock owners detected");
3782				ret = -EIO;
3783				goto out;
3784			}
3785
3786			lock_owner_responded = true;
3787			ret = ceph_start_decoding(&p, end, 1, "ResponseMessage",
3788						  &struct_v, &len);
3789			if (ret) {
3790				rbd_warn(rbd_dev,
3791					 "failed to decode ResponseMessage: %d",
3792					 ret);
3793				goto e_inval;
3794			}
3795
3796			ret = ceph_decode_32(&p);
3797		}
3798	}
3799
3800	if (!lock_owner_responded) {
3801		rbd_warn(rbd_dev, "no lock owners detected");
3802		ret = -ETIMEDOUT;
3803	}
3804
3805out:
3806	ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
3807	return ret;
3808
3809e_inval:
3810	ret = -EINVAL;
3811	goto out;
3812}
3813
3814/*
3815 * Either image request state machine(s) or rbd_add_acquire_lock()
3816 * (i.e. "rbd map").
3817 */
3818static void wake_lock_waiters(struct rbd_device *rbd_dev, int result)
 
 
3819{
3820	struct rbd_img_request *img_req;
3821
3822	dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
3823	lockdep_assert_held_write(&rbd_dev->lock_rwsem);
3824
3825	cancel_delayed_work(&rbd_dev->lock_dwork);
3826	if (!completion_done(&rbd_dev->acquire_wait)) {
3827		rbd_assert(list_empty(&rbd_dev->acquiring_list) &&
3828			   list_empty(&rbd_dev->running_list));
3829		rbd_dev->acquire_err = result;
3830		complete_all(&rbd_dev->acquire_wait);
3831		return;
3832	}
3833
3834	list_for_each_entry(img_req, &rbd_dev->acquiring_list, lock_item) {
3835		mutex_lock(&img_req->state_mutex);
3836		rbd_assert(img_req->state == RBD_IMG_EXCLUSIVE_LOCK);
3837		rbd_img_schedule(img_req, result);
3838		mutex_unlock(&img_req->state_mutex);
3839	}
3840
3841	list_splice_tail_init(&rbd_dev->acquiring_list, &rbd_dev->running_list);
3842}
3843
3844static int get_lock_owner_info(struct rbd_device *rbd_dev,
3845			       struct ceph_locker **lockers, u32 *num_lockers)
3846{
3847	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3848	u8 lock_type;
3849	char *lock_tag;
3850	int ret;
3851
3852	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3853
3854	ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
3855				 &rbd_dev->header_oloc, RBD_LOCK_NAME,
3856				 &lock_type, &lock_tag, lockers, num_lockers);
3857	if (ret)
3858		return ret;
3859
3860	if (*num_lockers == 0) {
3861		dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
3862		goto out;
3863	}
3864
3865	if (strcmp(lock_tag, RBD_LOCK_TAG)) {
3866		rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
3867			 lock_tag);
3868		ret = -EBUSY;
3869		goto out;
3870	}
3871
3872	if (lock_type == CEPH_CLS_LOCK_SHARED) {
3873		rbd_warn(rbd_dev, "shared lock type detected");
3874		ret = -EBUSY;
3875		goto out;
3876	}
 
3877
3878	if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX,
3879		    strlen(RBD_LOCK_COOKIE_PREFIX))) {
3880		rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
3881			 (*lockers)[0].id.cookie);
3882		ret = -EBUSY;
3883		goto out;
3884	}
3885
3886out:
3887	kfree(lock_tag);
3888	return ret;
3889}
3890
3891static int find_watcher(struct rbd_device *rbd_dev,
3892			const struct ceph_locker *locker)
3893{
3894	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3895	struct ceph_watch_item *watchers;
3896	u32 num_watchers;
3897	u64 cookie;
3898	int i;
3899	int ret;
3900
3901	ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid,
3902				      &rbd_dev->header_oloc, &watchers,
3903				      &num_watchers);
3904	if (ret)
3905		return ret;
3906
3907	sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie);
3908	for (i = 0; i < num_watchers; i++) {
3909		/*
3910		 * Ignore addr->type while comparing.  This mimics
3911		 * entity_addr_t::get_legacy_str() + strcmp().
3912		 */
3913		if (ceph_addr_equal_no_type(&watchers[i].addr,
3914					    &locker->info.addr) &&
3915		    watchers[i].cookie == cookie) {
3916			struct rbd_client_id cid = {
3917				.gid = le64_to_cpu(watchers[i].name.num),
3918				.handle = cookie,
3919			};
3920
3921			dout("%s rbd_dev %p found cid %llu-%llu\n", __func__,
3922			     rbd_dev, cid.gid, cid.handle);
3923			rbd_set_owner_cid(rbd_dev, &cid);
3924			ret = 1;
3925			goto out;
3926		}
3927	}
3928
3929	dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev);
3930	ret = 0;
3931out:
3932	kfree(watchers);
3933	return ret;
3934}
3935
3936/*
3937 * lock_rwsem must be held for write
3938 */
3939static int rbd_try_lock(struct rbd_device *rbd_dev)
 
 
 
 
 
 
3940{
3941	struct ceph_client *client = rbd_dev->rbd_client->client;
3942	struct ceph_locker *lockers;
3943	u32 num_lockers;
3944	int ret;
3945
3946	for (;;) {
3947		ret = rbd_lock(rbd_dev);
3948		if (ret != -EBUSY)
3949			return ret;
3950
3951		/* determine if the current lock holder is still alive */
3952		ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers);
3953		if (ret)
3954			return ret;
3955
3956		if (num_lockers == 0)
3957			goto again;
3958
3959		ret = find_watcher(rbd_dev, lockers);
3960		if (ret)
3961			goto out; /* request lock or error */
3962
3963		rbd_warn(rbd_dev, "breaking header lock owned by %s%llu",
3964			 ENTITY_NAME(lockers[0].id.name));
3965
3966		ret = ceph_monc_blocklist_add(&client->monc,
3967					      &lockers[0].info.addr);
3968		if (ret) {
3969			rbd_warn(rbd_dev, "blocklist of %s%llu failed: %d",
3970				 ENTITY_NAME(lockers[0].id.name), ret);
3971			goto out;
3972		}
3973
3974		ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
3975					  &rbd_dev->header_oloc, RBD_LOCK_NAME,
3976					  lockers[0].id.cookie,
3977					  &lockers[0].id.name);
3978		if (ret && ret != -ENOENT)
3979			goto out;
3980
3981again:
3982		ceph_free_lockers(lockers, num_lockers);
3983	}
3984
3985out:
3986	ceph_free_lockers(lockers, num_lockers);
3987	return ret;
3988}
3989
3990static int rbd_post_acquire_action(struct rbd_device *rbd_dev)
3991{
3992	int ret;
 
 
 
3993
3994	if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) {
3995		ret = rbd_object_map_open(rbd_dev);
3996		if (ret)
3997			return ret;
3998	}
3999
4000	return 0;
4001}
4002
4003/*
4004 * Return:
4005 *   0 - lock acquired
4006 *   1 - caller should call rbd_request_lock()
4007 *  <0 - error
4008 */
4009static int rbd_try_acquire_lock(struct rbd_device *rbd_dev)
4010{
4011	int ret;
 
 
4012
4013	down_read(&rbd_dev->lock_rwsem);
4014	dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
4015	     rbd_dev->lock_state);
4016	if (__rbd_is_lock_owner(rbd_dev)) {
4017		up_read(&rbd_dev->lock_rwsem);
4018		return 0;
4019	}
4020
4021	up_read(&rbd_dev->lock_rwsem);
4022	down_write(&rbd_dev->lock_rwsem);
4023	dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
4024	     rbd_dev->lock_state);
4025	if (__rbd_is_lock_owner(rbd_dev)) {
4026		up_write(&rbd_dev->lock_rwsem);
4027		return 0;
4028	}
4029
4030	ret = rbd_try_lock(rbd_dev);
4031	if (ret < 0) {
4032		rbd_warn(rbd_dev, "failed to lock header: %d", ret);
4033		if (ret == -EBLOCKLISTED)
4034			goto out;
4035
4036		ret = 1; /* request lock anyway */
4037	}
4038	if (ret > 0) {
4039		up_write(&rbd_dev->lock_rwsem);
4040		return ret;
4041	}
4042
4043	rbd_assert(rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED);
4044	rbd_assert(list_empty(&rbd_dev->running_list));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4045
4046	ret = rbd_post_acquire_action(rbd_dev);
4047	if (ret) {
4048		rbd_warn(rbd_dev, "post-acquire action failed: %d", ret);
4049		/*
4050		 * Can't stay in RBD_LOCK_STATE_LOCKED because
4051		 * rbd_lock_add_request() would let the request through,
4052		 * assuming that e.g. object map is locked and loaded.
4053		 */
4054		rbd_unlock(rbd_dev);
4055	}
4056
4057out:
4058	wake_lock_waiters(rbd_dev, ret);
4059	up_write(&rbd_dev->lock_rwsem);
4060	return ret;
4061}
4062
4063static void rbd_acquire_lock(struct work_struct *work)
4064{
4065	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4066					    struct rbd_device, lock_dwork);
4067	int ret;
4068
4069	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4070again:
4071	ret = rbd_try_acquire_lock(rbd_dev);
4072	if (ret <= 0) {
4073		dout("%s rbd_dev %p ret %d - done\n", __func__, rbd_dev, ret);
4074		return;
 
 
 
 
 
 
 
 
 
 
4075	}
4076
4077	ret = rbd_request_lock(rbd_dev);
4078	if (ret == -ETIMEDOUT) {
4079		goto again; /* treat this as a dead client */
4080	} else if (ret == -EROFS) {
4081		rbd_warn(rbd_dev, "peer will not release lock");
4082		down_write(&rbd_dev->lock_rwsem);
4083		wake_lock_waiters(rbd_dev, ret);
4084		up_write(&rbd_dev->lock_rwsem);
4085	} else if (ret < 0) {
4086		rbd_warn(rbd_dev, "error requesting lock: %d", ret);
4087		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4088				 RBD_RETRY_DELAY);
4089	} else {
4090		/*
4091		 * lock owner acked, but resend if we don't see them
4092		 * release the lock
4093		 */
4094		dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
4095		     rbd_dev);
4096		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4097		    msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
4098	}
4099}
4100
4101static bool rbd_quiesce_lock(struct rbd_device *rbd_dev)
4102{
4103	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4104	lockdep_assert_held_write(&rbd_dev->lock_rwsem);
4105
4106	if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED)
4107		return false;
4108
4109	/*
4110	 * Ensure that all in-flight IO is flushed.
4111	 */
4112	rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING;
4113	rbd_assert(!completion_done(&rbd_dev->releasing_wait));
4114	if (list_empty(&rbd_dev->running_list))
4115		return true;
4116
4117	up_write(&rbd_dev->lock_rwsem);
4118	wait_for_completion(&rbd_dev->releasing_wait);
4119
4120	down_write(&rbd_dev->lock_rwsem);
4121	if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING)
4122		return false;
4123
4124	rbd_assert(list_empty(&rbd_dev->running_list));
4125	return true;
4126}
4127
4128static void rbd_pre_release_action(struct rbd_device *rbd_dev)
4129{
4130	if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)
4131		rbd_object_map_close(rbd_dev);
4132}
4133
4134static void __rbd_release_lock(struct rbd_device *rbd_dev)
4135{
4136	rbd_assert(list_empty(&rbd_dev->running_list));
4137
4138	rbd_pre_release_action(rbd_dev);
4139	rbd_unlock(rbd_dev);
4140}
4141
4142/*
4143 * lock_rwsem must be held for write
4144 */
4145static void rbd_release_lock(struct rbd_device *rbd_dev)
4146{
4147	if (!rbd_quiesce_lock(rbd_dev))
4148		return;
4149
4150	__rbd_release_lock(rbd_dev);
4151
4152	/*
4153	 * Give others a chance to grab the lock - we would re-acquire
4154	 * almost immediately if we got new IO while draining the running
4155	 * list otherwise.  We need to ack our own notifications, so this
4156	 * lock_dwork will be requeued from rbd_handle_released_lock() by
4157	 * way of maybe_kick_acquire().
4158	 */
4159	cancel_delayed_work(&rbd_dev->lock_dwork);
 
 
 
4160}
4161
4162static void rbd_release_lock_work(struct work_struct *work)
4163{
4164	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
4165						  unlock_work);
4166
4167	down_write(&rbd_dev->lock_rwsem);
4168	rbd_release_lock(rbd_dev);
4169	up_write(&rbd_dev->lock_rwsem);
4170}
4171
4172static void maybe_kick_acquire(struct rbd_device *rbd_dev)
4173{
4174	bool have_requests;
4175
4176	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4177	if (__rbd_is_lock_owner(rbd_dev))
4178		return;
4179
4180	spin_lock(&rbd_dev->lock_lists_lock);
4181	have_requests = !list_empty(&rbd_dev->acquiring_list);
4182	spin_unlock(&rbd_dev->lock_lists_lock);
4183	if (have_requests || delayed_work_pending(&rbd_dev->lock_dwork)) {
4184		dout("%s rbd_dev %p kicking lock_dwork\n", __func__, rbd_dev);
4185		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4186	}
4187}
4188
4189static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v,
4190				     void **p)
4191{
4192	struct rbd_client_id cid = { 0 };
4193
4194	if (struct_v >= 2) {
4195		cid.gid = ceph_decode_64(p);
4196		cid.handle = ceph_decode_64(p);
4197	}
4198
4199	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4200	     cid.handle);
4201	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4202		down_write(&rbd_dev->lock_rwsem);
4203		if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4204			dout("%s rbd_dev %p cid %llu-%llu == owner_cid\n",
4205			     __func__, rbd_dev, cid.gid, cid.handle);
4206		} else {
4207			rbd_set_owner_cid(rbd_dev, &cid);
4208		}
4209		downgrade_write(&rbd_dev->lock_rwsem);
4210	} else {
4211		down_read(&rbd_dev->lock_rwsem);
4212	}
4213
4214	maybe_kick_acquire(rbd_dev);
4215	up_read(&rbd_dev->lock_rwsem);
4216}
4217
4218static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v,
4219				     void **p)
4220{
4221	struct rbd_client_id cid = { 0 };
4222
4223	if (struct_v >= 2) {
4224		cid.gid = ceph_decode_64(p);
4225		cid.handle = ceph_decode_64(p);
4226	}
4227
4228	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4229	     cid.handle);
4230	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4231		down_write(&rbd_dev->lock_rwsem);
4232		if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4233			dout("%s rbd_dev %p cid %llu-%llu != owner_cid %llu-%llu\n",
4234			     __func__, rbd_dev, cid.gid, cid.handle,
4235			     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle);
4236		} else {
4237			rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4238		}
4239		downgrade_write(&rbd_dev->lock_rwsem);
4240	} else {
4241		down_read(&rbd_dev->lock_rwsem);
4242	}
4243
4244	maybe_kick_acquire(rbd_dev);
4245	up_read(&rbd_dev->lock_rwsem);
4246}
4247
4248/*
4249 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no
4250 * ResponseMessage is needed.
4251 */
4252static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v,
4253				   void **p)
4254{
4255	struct rbd_client_id my_cid = rbd_get_cid(rbd_dev);
4256	struct rbd_client_id cid = { 0 };
4257	int result = 1;
 
 
4258
4259	if (struct_v >= 2) {
4260		cid.gid = ceph_decode_64(p);
4261		cid.handle = ceph_decode_64(p);
4262	}
4263
4264	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4265	     cid.handle);
4266	if (rbd_cid_equal(&cid, &my_cid))
4267		return result;
4268
4269	down_read(&rbd_dev->lock_rwsem);
4270	if (__rbd_is_lock_owner(rbd_dev)) {
4271		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED &&
4272		    rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid))
4273			goto out_unlock;
4274
4275		/*
4276		 * encode ResponseMessage(0) so the peer can detect
4277		 * a missing owner
4278		 */
4279		result = 0;
4280
4281		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) {
4282			if (!rbd_dev->opts->exclusive) {
4283				dout("%s rbd_dev %p queueing unlock_work\n",
4284				     __func__, rbd_dev);
4285				queue_work(rbd_dev->task_wq,
4286					   &rbd_dev->unlock_work);
4287			} else {
4288				/* refuse to release the lock */
4289				result = -EROFS;
4290			}
4291		}
4292	}
4293
4294out_unlock:
4295	up_read(&rbd_dev->lock_rwsem);
4296	return result;
4297}
4298
4299static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev,
4300				     u64 notify_id, u64 cookie, s32 *result)
4301{
4302	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4303	char buf[4 + CEPH_ENCODING_START_BLK_LEN];
4304	int buf_size = sizeof(buf);
4305	int ret;
4306
4307	if (result) {
4308		void *p = buf;
4309
4310		/* encode ResponseMessage */
4311		ceph_start_encoding(&p, 1, 1,
4312				    buf_size - CEPH_ENCODING_START_BLK_LEN);
4313		ceph_encode_32(&p, *result);
4314	} else {
4315		buf_size = 0;
4316	}
4317
4318	ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid,
4319				   &rbd_dev->header_oloc, notify_id, cookie,
4320				   buf, buf_size);
4321	if (ret)
4322		rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret);
4323}
4324
4325static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id,
4326				   u64 cookie)
4327{
4328	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4329	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL);
4330}
4331
4332static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev,
4333					  u64 notify_id, u64 cookie, s32 result)
4334{
4335	dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
4336	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result);
4337}
4338
4339static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie,
4340			 u64 notifier_id, void *data, size_t data_len)
4341{
4342	struct rbd_device *rbd_dev = arg;
4343	void *p = data;
4344	void *const end = p + data_len;
4345	u8 struct_v = 0;
4346	u32 len;
4347	u32 notify_op;
4348	int ret;
4349
4350	dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n",
4351	     __func__, rbd_dev, cookie, notify_id, data_len);
4352	if (data_len) {
4353		ret = ceph_start_decoding(&p, end, 1, "NotifyMessage",
4354					  &struct_v, &len);
4355		if (ret) {
4356			rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d",
4357				 ret);
4358			return;
4359		}
4360
4361		notify_op = ceph_decode_32(&p);
4362	} else {
4363		/* legacy notification for header updates */
4364		notify_op = RBD_NOTIFY_OP_HEADER_UPDATE;
4365		len = 0;
4366	}
4367
4368	dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op);
4369	switch (notify_op) {
4370	case RBD_NOTIFY_OP_ACQUIRED_LOCK:
4371		rbd_handle_acquired_lock(rbd_dev, struct_v, &p);
4372		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4373		break;
4374	case RBD_NOTIFY_OP_RELEASED_LOCK:
4375		rbd_handle_released_lock(rbd_dev, struct_v, &p);
4376		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4377		break;
4378	case RBD_NOTIFY_OP_REQUEST_LOCK:
4379		ret = rbd_handle_request_lock(rbd_dev, struct_v, &p);
4380		if (ret <= 0)
4381			rbd_acknowledge_notify_result(rbd_dev, notify_id,
4382						      cookie, ret);
4383		else
4384			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4385		break;
4386	case RBD_NOTIFY_OP_HEADER_UPDATE:
4387		ret = rbd_dev_refresh(rbd_dev);
4388		if (ret)
4389			rbd_warn(rbd_dev, "refresh failed: %d", ret);
4390
4391		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4392		break;
4393	default:
4394		if (rbd_is_lock_owner(rbd_dev))
4395			rbd_acknowledge_notify_result(rbd_dev, notify_id,
4396						      cookie, -EOPNOTSUPP);
4397		else
4398			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4399		break;
4400	}
4401}
4402
4403static void __rbd_unregister_watch(struct rbd_device *rbd_dev);
4404
4405static void rbd_watch_errcb(void *arg, u64 cookie, int err)
4406{
4407	struct rbd_device *rbd_dev = arg;
4408
4409	rbd_warn(rbd_dev, "encountered watch error: %d", err);
4410
4411	down_write(&rbd_dev->lock_rwsem);
4412	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4413	up_write(&rbd_dev->lock_rwsem);
4414
4415	mutex_lock(&rbd_dev->watch_mutex);
4416	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) {
4417		__rbd_unregister_watch(rbd_dev);
4418		rbd_dev->watch_state = RBD_WATCH_STATE_ERROR;
4419
4420		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0);
4421	}
4422	mutex_unlock(&rbd_dev->watch_mutex);
4423}
4424
4425/*
4426 * watch_mutex must be locked
4427 */
4428static int __rbd_register_watch(struct rbd_device *rbd_dev)
 
 
4429{
4430	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4431	struct ceph_osd_linger_request *handle;
 
 
 
4432
4433	rbd_assert(!rbd_dev->watch_handle);
4434	dout("%s rbd_dev %p\n", __func__, rbd_dev);
 
4435
4436	handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid,
4437				 &rbd_dev->header_oloc, rbd_watch_cb,
4438				 rbd_watch_errcb, rbd_dev);
4439	if (IS_ERR(handle))
4440		return PTR_ERR(handle);
4441
4442	rbd_dev->watch_handle = handle;
4443	return 0;
4444}
4445
4446/*
4447 * watch_mutex must be locked
4448 */
4449static void __rbd_unregister_watch(struct rbd_device *rbd_dev)
4450{
4451	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4452	int ret;
4453
4454	rbd_assert(rbd_dev->watch_handle);
4455	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4456
4457	ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle);
4458	if (ret)
4459		rbd_warn(rbd_dev, "failed to unwatch: %d", ret);
4460
4461	rbd_dev->watch_handle = NULL;
4462}
4463
4464static int rbd_register_watch(struct rbd_device *rbd_dev)
4465{
4466	int ret;
4467
4468	mutex_lock(&rbd_dev->watch_mutex);
4469	rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED);
4470	ret = __rbd_register_watch(rbd_dev);
4471	if (ret)
4472		goto out;
4473
4474	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4475	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4476
4477out:
4478	mutex_unlock(&rbd_dev->watch_mutex);
4479	return ret;
4480}
4481
4482static void cancel_tasks_sync(struct rbd_device *rbd_dev)
4483{
4484	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4485
4486	cancel_work_sync(&rbd_dev->acquired_lock_work);
4487	cancel_work_sync(&rbd_dev->released_lock_work);
4488	cancel_delayed_work_sync(&rbd_dev->lock_dwork);
4489	cancel_work_sync(&rbd_dev->unlock_work);
4490}
4491
4492/*
4493 * header_rwsem must not be held to avoid a deadlock with
4494 * rbd_dev_refresh() when flushing notifies.
4495 */
4496static void rbd_unregister_watch(struct rbd_device *rbd_dev)
4497{
4498	cancel_tasks_sync(rbd_dev);
4499
4500	mutex_lock(&rbd_dev->watch_mutex);
4501	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED)
4502		__rbd_unregister_watch(rbd_dev);
4503	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
4504	mutex_unlock(&rbd_dev->watch_mutex);
4505
4506	cancel_delayed_work_sync(&rbd_dev->watch_dwork);
4507	ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
4508}
4509
4510/*
4511 * lock_rwsem must be held for write
4512 */
4513static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
4514{
4515	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4516	char cookie[32];
4517	int ret;
 
 
 
4518
4519	if (!rbd_quiesce_lock(rbd_dev))
4520		return;
4521
4522	format_lock_cookie(rbd_dev, cookie);
4523	ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid,
4524				  &rbd_dev->header_oloc, RBD_LOCK_NAME,
4525				  CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie,
4526				  RBD_LOCK_TAG, cookie);
4527	if (ret) {
4528		if (ret != -EOPNOTSUPP)
4529			rbd_warn(rbd_dev, "failed to update lock cookie: %d",
4530				 ret);
4531
4532		/*
4533		 * Lock cookie cannot be updated on older OSDs, so do
4534		 * a manual release and queue an acquire.
4535		 */
4536		__rbd_release_lock(rbd_dev);
4537		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4538	} else {
4539		__rbd_lock(rbd_dev, cookie);
4540		wake_lock_waiters(rbd_dev, 0);
4541	}
4542}
4543
4544static void rbd_reregister_watch(struct work_struct *work)
4545{
4546	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4547					    struct rbd_device, watch_dwork);
4548	int ret;
4549
4550	dout("%s rbd_dev %p\n", __func__, rbd_dev);
4551
4552	mutex_lock(&rbd_dev->watch_mutex);
4553	if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) {
4554		mutex_unlock(&rbd_dev->watch_mutex);
4555		return;
4556	}
4557
4558	ret = __rbd_register_watch(rbd_dev);
4559	if (ret) {
4560		rbd_warn(rbd_dev, "failed to reregister watch: %d", ret);
4561		if (ret != -EBLOCKLISTED && ret != -ENOENT) {
4562			queue_delayed_work(rbd_dev->task_wq,
4563					   &rbd_dev->watch_dwork,
4564					   RBD_RETRY_DELAY);
4565			mutex_unlock(&rbd_dev->watch_mutex);
4566			return;
4567		}
4568
4569		mutex_unlock(&rbd_dev->watch_mutex);
4570		down_write(&rbd_dev->lock_rwsem);
4571		wake_lock_waiters(rbd_dev, ret);
4572		up_write(&rbd_dev->lock_rwsem);
4573		return;
4574	}
4575
4576	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4577	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4578	mutex_unlock(&rbd_dev->watch_mutex);
4579
4580	down_write(&rbd_dev->lock_rwsem);
4581	if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
4582		rbd_reacquire_lock(rbd_dev);
4583	up_write(&rbd_dev->lock_rwsem);
4584
4585	ret = rbd_dev_refresh(rbd_dev);
4586	if (ret)
4587		rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret);
4588}
4589
4590/*
4591 * Synchronous osd object method call.  Returns the number of bytes
4592 * returned in the outbound buffer, or a negative error code.
4593 */
4594static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
4595			     struct ceph_object_id *oid,
4596			     struct ceph_object_locator *oloc,
4597			     const char *method_name,
4598			     const void *outbound,
4599			     size_t outbound_size,
4600			     void *inbound,
4601			     size_t inbound_size)
4602{
4603	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4604	struct page *req_page = NULL;
4605	struct page *reply_page;
4606	int ret;
4607
4608	/*
4609	 * Method calls are ultimately read operations.  The result
4610	 * should placed into the inbound buffer provided.  They
4611	 * also supply outbound data--parameters for the object
4612	 * method.  Currently if this is present it will be a
4613	 * snapshot id.
4614	 */
4615	if (outbound) {
4616		if (outbound_size > PAGE_SIZE)
4617			return -E2BIG;
4618
4619		req_page = alloc_page(GFP_KERNEL);
4620		if (!req_page)
4621			return -ENOMEM;
4622
4623		memcpy(page_address(req_page), outbound, outbound_size);
4624	}
4625
4626	reply_page = alloc_page(GFP_KERNEL);
4627	if (!reply_page) {
4628		if (req_page)
4629			__free_page(req_page);
4630		return -ENOMEM;
4631	}
4632
4633	ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name,
4634			     CEPH_OSD_FLAG_READ, req_page, outbound_size,
4635			     &reply_page, &inbound_size);
4636	if (!ret) {
4637		memcpy(inbound, page_address(reply_page), inbound_size);
4638		ret = inbound_size;
4639	}
4640
4641	if (req_page)
4642		__free_page(req_page);
4643	__free_page(reply_page);
4644	return ret;
4645}
4646
4647static void rbd_queue_workfn(struct work_struct *work)
4648{
4649	struct rbd_img_request *img_request =
4650	    container_of(work, struct rbd_img_request, work);
4651	struct rbd_device *rbd_dev = img_request->rbd_dev;
4652	enum obj_operation_type op_type = img_request->op_type;
4653	struct request *rq = blk_mq_rq_from_pdu(img_request);
4654	u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
4655	u64 length = blk_rq_bytes(rq);
4656	u64 mapping_size;
4657	int result;
4658
4659	/* Ignore/skip any zero-length requests */
4660	if (!length) {
4661		dout("%s: zero-length request\n", __func__);
4662		result = 0;
4663		goto err_img_request;
4664	}
4665
4666	blk_mq_start_request(rq);
4667
4668	down_read(&rbd_dev->header_rwsem);
4669	mapping_size = rbd_dev->mapping.size;
4670	rbd_img_capture_header(img_request);
4671	up_read(&rbd_dev->header_rwsem);
4672
4673	if (offset + length > mapping_size) {
4674		rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
4675			 length, mapping_size);
4676		result = -EIO;
4677		goto err_img_request;
4678	}
4679
4680	dout("%s rbd_dev %p img_req %p %s %llu~%llu\n", __func__, rbd_dev,
4681	     img_request, obj_op_name(op_type), offset, length);
4682
4683	if (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_ZEROOUT)
4684		result = rbd_img_fill_nodata(img_request, offset, length);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4685	else
4686		result = rbd_img_fill_from_bio(img_request, offset, length,
4687					       rq->bio);
4688	if (result)
4689		goto err_img_request;
4690
4691	rbd_img_handle_request(img_request, 0);
4692	return;
4693
4694err_img_request:
4695	rbd_img_request_destroy(img_request);
4696	if (result)
4697		rbd_warn(rbd_dev, "%s %llx at %llx result %d",
4698			 obj_op_name(op_type), length, offset, result);
4699	blk_mq_end_request(rq, errno_to_blk_status(result));
4700}
4701
4702static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
4703		const struct blk_mq_queue_data *bd)
4704{
4705	struct rbd_device *rbd_dev = hctx->queue->queuedata;
4706	struct rbd_img_request *img_req = blk_mq_rq_to_pdu(bd->rq);
4707	enum obj_operation_type op_type;
4708
4709	switch (req_op(bd->rq)) {
4710	case REQ_OP_DISCARD:
4711		op_type = OBJ_OP_DISCARD;
4712		break;
4713	case REQ_OP_WRITE_ZEROES:
4714		op_type = OBJ_OP_ZEROOUT;
4715		break;
4716	case REQ_OP_WRITE:
4717		op_type = OBJ_OP_WRITE;
4718		break;
4719	case REQ_OP_READ:
4720		op_type = OBJ_OP_READ;
4721		break;
4722	default:
4723		rbd_warn(rbd_dev, "unknown req_op %d", req_op(bd->rq));
4724		return BLK_STS_IOERR;
4725	}
4726
4727	rbd_img_request_init(img_req, rbd_dev, op_type);
4728
4729	if (rbd_img_is_write(img_req)) {
4730		if (rbd_is_ro(rbd_dev)) {
4731			rbd_warn(rbd_dev, "%s on read-only mapping",
4732				 obj_op_name(img_req->op_type));
4733			return BLK_STS_IOERR;
4734		}
4735		rbd_assert(!rbd_is_snap(rbd_dev));
4736	}
4737
4738	INIT_WORK(&img_req->work, rbd_queue_workfn);
4739	queue_work(rbd_wq, &img_req->work);
4740	return BLK_STS_OK;
4741}
4742
4743static void rbd_free_disk(struct rbd_device *rbd_dev)
4744{
4745	blk_cleanup_disk(rbd_dev->disk);
4746	blk_mq_free_tag_set(&rbd_dev->tag_set);
4747	rbd_dev->disk = NULL;
4748}
4749
4750static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
4751			     struct ceph_object_id *oid,
4752			     struct ceph_object_locator *oloc,
4753			     void *buf, int buf_len)
4754
4755{
4756	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4757	struct ceph_osd_request *req;
4758	struct page **pages;
4759	int num_pages = calc_pages_for(0, buf_len);
4760	int ret;
4761
4762	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
4763	if (!req)
4764		return -ENOMEM;
4765
4766	ceph_oid_copy(&req->r_base_oid, oid);
4767	ceph_oloc_copy(&req->r_base_oloc, oloc);
4768	req->r_flags = CEPH_OSD_FLAG_READ;
4769
4770	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
4771	if (IS_ERR(pages)) {
4772		ret = PTR_ERR(pages);
4773		goto out_req;
4774	}
4775
4776	osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0);
4777	osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false,
4778					 true);
4779
4780	ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
4781	if (ret)
4782		goto out_req;
4783
4784	ceph_osdc_start_request(osdc, req, false);
4785	ret = ceph_osdc_wait_request(osdc, req);
4786	if (ret >= 0)
4787		ceph_copy_from_page_vector(pages, buf, 0, ret);
4788
4789out_req:
4790	ceph_osdc_put_request(req);
4791	return ret;
4792}
4793
4794/*
4795 * Read the complete header for the given rbd device.  On successful
4796 * return, the rbd_dev->header field will contain up-to-date
4797 * information about the image.
4798 */
4799static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
4800{
4801	struct rbd_image_header_ondisk *ondisk = NULL;
4802	u32 snap_count = 0;
4803	u64 names_size = 0;
4804	u32 want_count;
4805	int ret;
4806
4807	/*
4808	 * The complete header will include an array of its 64-bit
4809	 * snapshot ids, followed by the names of those snapshots as
4810	 * a contiguous block of NUL-terminated strings.  Note that
4811	 * the number of snapshots could change by the time we read
4812	 * it in, in which case we re-read it.
4813	 */
4814	do {
4815		size_t size;
4816
4817		kfree(ondisk);
4818
4819		size = sizeof (*ondisk);
4820		size += snap_count * sizeof (struct rbd_image_snap_ondisk);
4821		size += names_size;
4822		ondisk = kmalloc(size, GFP_KERNEL);
4823		if (!ondisk)
4824			return -ENOMEM;
4825
4826		ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid,
4827					&rbd_dev->header_oloc, ondisk, size);
4828		if (ret < 0)
4829			goto out;
4830		if ((size_t)ret < size) {
4831			ret = -ENXIO;
4832			rbd_warn(rbd_dev, "short header read (want %zd got %d)",
4833				size, ret);
4834			goto out;
4835		}
4836		if (!rbd_dev_ondisk_valid(ondisk)) {
4837			ret = -ENXIO;
4838			rbd_warn(rbd_dev, "invalid header");
4839			goto out;
4840		}
4841
4842		names_size = le64_to_cpu(ondisk->snap_names_len);
4843		want_count = snap_count;
4844		snap_count = le32_to_cpu(ondisk->snap_count);
4845	} while (snap_count != want_count);
4846
4847	ret = rbd_header_from_disk(rbd_dev, ondisk);
4848out:
4849	kfree(ondisk);
4850
4851	return ret;
4852}
4853
4854static void rbd_dev_update_size(struct rbd_device *rbd_dev)
4855{
4856	sector_t size;
 
 
 
4857
4858	/*
4859	 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't
4860	 * try to update its size.  If REMOVING is set, updating size
4861	 * is just useless work since the device can't be opened.
4862	 */
4863	if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) &&
4864	    !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
4865		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
4866		dout("setting size to %llu sectors", (unsigned long long)size);
4867		set_capacity_and_notify(rbd_dev->disk, size);
4868	}
4869}
4870
4871static int rbd_dev_refresh(struct rbd_device *rbd_dev)
4872{
4873	u64 mapping_size;
4874	int ret;
4875
4876	down_write(&rbd_dev->header_rwsem);
4877	mapping_size = rbd_dev->mapping.size;
 
4878
4879	ret = rbd_dev_header_info(rbd_dev);
4880	if (ret)
 
 
4881		goto out;
4882
4883	/*
4884	 * If there is a parent, see if it has disappeared due to the
4885	 * mapped image getting flattened.
4886	 */
4887	if (rbd_dev->parent) {
4888		ret = rbd_dev_v2_parent_info(rbd_dev);
4889		if (ret)
4890			goto out;
4891	}
4892
4893	rbd_assert(!rbd_is_snap(rbd_dev));
4894	rbd_dev->mapping.size = rbd_dev->header.image_size;
4895
4896out:
4897	up_write(&rbd_dev->header_rwsem);
4898	if (!ret && mapping_size != rbd_dev->mapping.size)
4899		rbd_dev_update_size(rbd_dev);
4900
4901	return ret;
4902}
4903
4904static const struct blk_mq_ops rbd_mq_ops = {
4905	.queue_rq	= rbd_queue_rq,
4906};
4907
4908static int rbd_init_disk(struct rbd_device *rbd_dev)
4909{
4910	struct gendisk *disk;
4911	struct request_queue *q;
4912	unsigned int objset_bytes =
4913	    rbd_dev->layout.object_size * rbd_dev->layout.stripe_count;
4914	int err;
4915
4916	memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
4917	rbd_dev->tag_set.ops = &rbd_mq_ops;
4918	rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
4919	rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
4920	rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
4921	rbd_dev->tag_set.nr_hw_queues = num_present_cpus();
4922	rbd_dev->tag_set.cmd_size = sizeof(struct rbd_img_request);
4923
4924	err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
4925	if (err)
4926		return err;
4927
4928	disk = blk_mq_alloc_disk(&rbd_dev->tag_set, rbd_dev);
4929	if (IS_ERR(disk)) {
4930		err = PTR_ERR(disk);
4931		goto out_tag_set;
4932	}
4933	q = disk->queue;
4934
4935	snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
4936		 rbd_dev->dev_id);
4937	disk->major = rbd_dev->major;
4938	disk->first_minor = rbd_dev->minor;
4939	if (single_major) {
4940		disk->minors = (1 << RBD_SINGLE_MAJOR_PART_SHIFT);
4941		disk->flags |= GENHD_FL_EXT_DEVT;
4942	} else {
4943		disk->minors = RBD_MINORS_PER_MAJOR;
4944	}
4945	disk->fops = &rbd_bd_ops;
4946	disk->private_data = rbd_dev;
4947
4948	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
4949	/* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
 
 
 
 
 
 
 
 
 
4950
4951	blk_queue_max_hw_sectors(q, objset_bytes >> SECTOR_SHIFT);
4952	q->limits.max_sectors = queue_max_hw_sectors(q);
4953	blk_queue_max_segments(q, USHRT_MAX);
4954	blk_queue_max_segment_size(q, UINT_MAX);
4955	blk_queue_io_min(q, rbd_dev->opts->alloc_size);
4956	blk_queue_io_opt(q, rbd_dev->opts->alloc_size);
4957
4958	if (rbd_dev->opts->trim) {
4959		blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
4960		q->limits.discard_granularity = rbd_dev->opts->alloc_size;
4961		blk_queue_max_discard_sectors(q, objset_bytes >> SECTOR_SHIFT);
4962		blk_queue_max_write_zeroes_sectors(q, objset_bytes >> SECTOR_SHIFT);
4963	}
4964
4965	if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
4966		blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
4967
4968	rbd_dev->disk = disk;
 
4969
 
 
 
 
 
 
4970	return 0;
4971out_tag_set:
4972	blk_mq_free_tag_set(&rbd_dev->tag_set);
4973	return err;
 
 
4974}
4975
4976/*
4977  sysfs
4978*/
4979
4980static struct rbd_device *dev_to_rbd_dev(struct device *dev)
4981{
4982	return container_of(dev, struct rbd_device, dev);
4983}
4984
4985static ssize_t rbd_size_show(struct device *dev,
4986			     struct device_attribute *attr, char *buf)
4987{
4988	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4989
4990	return sprintf(buf, "%llu\n",
4991		(unsigned long long)rbd_dev->mapping.size);
4992}
4993
4994static ssize_t rbd_features_show(struct device *dev,
4995			     struct device_attribute *attr, char *buf)
4996{
4997	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4998
4999	return sprintf(buf, "0x%016llx\n", rbd_dev->header.features);
5000}
5001
5002static ssize_t rbd_major_show(struct device *dev,
5003			      struct device_attribute *attr, char *buf)
5004{
5005	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5006
5007	if (rbd_dev->major)
5008		return sprintf(buf, "%d\n", rbd_dev->major);
5009
5010	return sprintf(buf, "(none)\n");
5011}
5012
5013static ssize_t rbd_minor_show(struct device *dev,
5014			      struct device_attribute *attr, char *buf)
5015{
5016	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5017
5018	return sprintf(buf, "%d\n", rbd_dev->minor);
5019}
5020
5021static ssize_t rbd_client_addr_show(struct device *dev,
5022				    struct device_attribute *attr, char *buf)
5023{
5024	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5025	struct ceph_entity_addr *client_addr =
5026	    ceph_client_addr(rbd_dev->rbd_client->client);
5027
5028	return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr,
5029		       le32_to_cpu(client_addr->nonce));
5030}
5031
5032static ssize_t rbd_client_id_show(struct device *dev,
5033				  struct device_attribute *attr, char *buf)
5034{
5035	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5036
5037	return sprintf(buf, "client%lld\n",
5038		       ceph_client_gid(rbd_dev->rbd_client->client));
5039}
5040
5041static ssize_t rbd_cluster_fsid_show(struct device *dev,
5042				     struct device_attribute *attr, char *buf)
5043{
5044	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5045
5046	return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid);
5047}
5048
5049static ssize_t rbd_config_info_show(struct device *dev,
5050				    struct device_attribute *attr, char *buf)
5051{
5052	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5053
5054	if (!capable(CAP_SYS_ADMIN))
5055		return -EPERM;
5056
5057	return sprintf(buf, "%s\n", rbd_dev->config_info);
5058}
5059
5060static ssize_t rbd_pool_show(struct device *dev,
5061			     struct device_attribute *attr, char *buf)
5062{
5063	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5064
5065	return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
5066}
5067
5068static ssize_t rbd_pool_id_show(struct device *dev,
5069			     struct device_attribute *attr, char *buf)
5070{
5071	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5072
5073	return sprintf(buf, "%llu\n",
5074			(unsigned long long) rbd_dev->spec->pool_id);
5075}
5076
5077static ssize_t rbd_pool_ns_show(struct device *dev,
5078				struct device_attribute *attr, char *buf)
5079{
5080	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5081
5082	return sprintf(buf, "%s\n", rbd_dev->spec->pool_ns ?: "");
5083}
5084
5085static ssize_t rbd_name_show(struct device *dev,
5086			     struct device_attribute *attr, char *buf)
5087{
5088	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5089
5090	if (rbd_dev->spec->image_name)
5091		return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
5092
5093	return sprintf(buf, "(unknown)\n");
5094}
5095
5096static ssize_t rbd_image_id_show(struct device *dev,
5097			     struct device_attribute *attr, char *buf)
5098{
5099	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5100
5101	return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
5102}
5103
5104/*
5105 * Shows the name of the currently-mapped snapshot (or
5106 * RBD_SNAP_HEAD_NAME for the base image).
5107 */
5108static ssize_t rbd_snap_show(struct device *dev,
5109			     struct device_attribute *attr,
5110			     char *buf)
5111{
5112	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5113
5114	return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
5115}
5116
5117static ssize_t rbd_snap_id_show(struct device *dev,
5118				struct device_attribute *attr, char *buf)
5119{
5120	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5121
5122	return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id);
5123}
5124
5125/*
5126 * For a v2 image, shows the chain of parent images, separated by empty
5127 * lines.  For v1 images or if there is no parent, shows "(no parent
5128 * image)".
5129 */
5130static ssize_t rbd_parent_show(struct device *dev,
5131			       struct device_attribute *attr,
5132			       char *buf)
5133{
5134	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5135	ssize_t count = 0;
5136
5137	if (!rbd_dev->parent)
5138		return sprintf(buf, "(no parent image)\n");
5139
5140	for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
5141		struct rbd_spec *spec = rbd_dev->parent_spec;
5142
5143		count += sprintf(&buf[count], "%s"
5144			    "pool_id %llu\npool_name %s\n"
5145			    "pool_ns %s\n"
5146			    "image_id %s\nimage_name %s\n"
5147			    "snap_id %llu\nsnap_name %s\n"
5148			    "overlap %llu\n",
5149			    !count ? "" : "\n", /* first? */
5150			    spec->pool_id, spec->pool_name,
5151			    spec->pool_ns ?: "",
5152			    spec->image_id, spec->image_name ?: "(unknown)",
5153			    spec->snap_id, spec->snap_name,
5154			    rbd_dev->parent_overlap);
5155	}
5156
5157	return count;
5158}
5159
5160static ssize_t rbd_image_refresh(struct device *dev,
5161				 struct device_attribute *attr,
5162				 const char *buf,
5163				 size_t size)
5164{
5165	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5166	int ret;
 
5167
5168	if (!capable(CAP_SYS_ADMIN))
5169		return -EPERM;
5170
5171	ret = rbd_dev_refresh(rbd_dev);
5172	if (ret)
5173		return ret;
5174
5175	return size;
 
5176}
5177
5178static DEVICE_ATTR(size, 0444, rbd_size_show, NULL);
5179static DEVICE_ATTR(features, 0444, rbd_features_show, NULL);
5180static DEVICE_ATTR(major, 0444, rbd_major_show, NULL);
5181static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL);
5182static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL);
5183static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL);
5184static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL);
5185static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL);
5186static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL);
5187static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL);
5188static DEVICE_ATTR(pool_ns, 0444, rbd_pool_ns_show, NULL);
5189static DEVICE_ATTR(name, 0444, rbd_name_show, NULL);
5190static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL);
5191static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh);
5192static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL);
5193static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL);
5194static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL);
5195
5196static struct attribute *rbd_attrs[] = {
5197	&dev_attr_size.attr,
5198	&dev_attr_features.attr,
5199	&dev_attr_major.attr,
5200	&dev_attr_minor.attr,
5201	&dev_attr_client_addr.attr,
5202	&dev_attr_client_id.attr,
5203	&dev_attr_cluster_fsid.attr,
5204	&dev_attr_config_info.attr,
5205	&dev_attr_pool.attr,
5206	&dev_attr_pool_id.attr,
5207	&dev_attr_pool_ns.attr,
5208	&dev_attr_name.attr,
5209	&dev_attr_image_id.attr,
5210	&dev_attr_current_snap.attr,
5211	&dev_attr_snap_id.attr,
5212	&dev_attr_parent.attr,
5213	&dev_attr_refresh.attr,
 
 
5214	NULL
5215};
5216
5217static struct attribute_group rbd_attr_group = {
5218	.attrs = rbd_attrs,
5219};
5220
5221static const struct attribute_group *rbd_attr_groups[] = {
5222	&rbd_attr_group,
5223	NULL
5224};
5225
5226static void rbd_dev_release(struct device *dev);
 
 
5227
5228static const struct device_type rbd_device_type = {
5229	.name		= "rbd",
5230	.groups		= rbd_attr_groups,
5231	.release	= rbd_dev_release,
5232};
5233
5234static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
5235{
5236	kref_get(&spec->kref);
5237
5238	return spec;
5239}
 
5240
5241static void rbd_spec_free(struct kref *kref);
5242static void rbd_spec_put(struct rbd_spec *spec)
 
5243{
5244	if (spec)
5245		kref_put(&spec->kref, rbd_spec_free);
5246}
5247
5248static struct rbd_spec *rbd_spec_alloc(void)
5249{
5250	struct rbd_spec *spec;
5251
5252	spec = kzalloc(sizeof (*spec), GFP_KERNEL);
5253	if (!spec)
5254		return NULL;
5255
5256	spec->pool_id = CEPH_NOPOOL;
5257	spec->snap_id = CEPH_NOSNAP;
5258	kref_init(&spec->kref);
5259
5260	return spec;
5261}
5262
5263static void rbd_spec_free(struct kref *kref)
 
 
5264{
5265	struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
5266
5267	kfree(spec->pool_name);
5268	kfree(spec->pool_ns);
5269	kfree(spec->image_id);
5270	kfree(spec->image_name);
5271	kfree(spec->snap_name);
5272	kfree(spec);
5273}
5274
5275static void rbd_dev_free(struct rbd_device *rbd_dev)
5276{
5277	WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED);
5278	WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED);
5279
5280	ceph_oid_destroy(&rbd_dev->header_oid);
5281	ceph_oloc_destroy(&rbd_dev->header_oloc);
5282	kfree(rbd_dev->config_info);
 
 
5283
5284	rbd_put_client(rbd_dev->rbd_client);
5285	rbd_spec_put(rbd_dev->spec);
5286	kfree(rbd_dev->opts);
5287	kfree(rbd_dev);
5288}
5289
5290static void rbd_dev_release(struct device *dev)
5291{
5292	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5293	bool need_put = !!rbd_dev->opts;
5294
5295	if (need_put) {
5296		destroy_workqueue(rbd_dev->task_wq);
5297		ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
5298	}
5299
5300	rbd_dev_free(rbd_dev);
5301
5302	/*
5303	 * This is racy, but way better than putting module outside of
5304	 * the release callback.  The race window is pretty small, so
5305	 * doing something similar to dm (dm-builtin.c) is overkill.
5306	 */
5307	if (need_put)
5308		module_put(THIS_MODULE);
5309}
5310
5311static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc,
5312					   struct rbd_spec *spec)
5313{
5314	struct rbd_device *rbd_dev;
5315
5316	rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
5317	if (!rbd_dev)
5318		return NULL;
5319
5320	spin_lock_init(&rbd_dev->lock);
5321	INIT_LIST_HEAD(&rbd_dev->node);
5322	init_rwsem(&rbd_dev->header_rwsem);
5323
5324	rbd_dev->header.data_pool_id = CEPH_NOPOOL;
5325	ceph_oid_init(&rbd_dev->header_oid);
5326	rbd_dev->header_oloc.pool = spec->pool_id;
5327	if (spec->pool_ns) {
5328		WARN_ON(!*spec->pool_ns);
5329		rbd_dev->header_oloc.pool_ns =
5330		    ceph_find_or_create_string(spec->pool_ns,
5331					       strlen(spec->pool_ns));
5332	}
5333
5334	mutex_init(&rbd_dev->watch_mutex);
5335	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
5336	INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch);
5337
5338	init_rwsem(&rbd_dev->lock_rwsem);
5339	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
5340	INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock);
5341	INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock);
5342	INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock);
5343	INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work);
5344	spin_lock_init(&rbd_dev->lock_lists_lock);
5345	INIT_LIST_HEAD(&rbd_dev->acquiring_list);
5346	INIT_LIST_HEAD(&rbd_dev->running_list);
5347	init_completion(&rbd_dev->acquire_wait);
5348	init_completion(&rbd_dev->releasing_wait);
5349
5350	spin_lock_init(&rbd_dev->object_map_lock);
5351
5352	rbd_dev->dev.bus = &rbd_bus_type;
5353	rbd_dev->dev.type = &rbd_device_type;
5354	rbd_dev->dev.parent = &rbd_root_dev;
5355	device_initialize(&rbd_dev->dev);
5356
5357	rbd_dev->rbd_client = rbdc;
5358	rbd_dev->spec = spec;
5359
5360	return rbd_dev;
5361}
5362
5363/*
5364 * Create a mapping rbd_dev.
5365 */
5366static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
5367					 struct rbd_spec *spec,
5368					 struct rbd_options *opts)
5369{
5370	struct rbd_device *rbd_dev;
5371
5372	rbd_dev = __rbd_dev_create(rbdc, spec);
5373	if (!rbd_dev)
5374		return NULL;
5375
5376	rbd_dev->opts = opts;
5377
5378	/* get an id and fill in device name */
5379	rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0,
5380					 minor_to_rbd_dev_id(1 << MINORBITS),
5381					 GFP_KERNEL);
5382	if (rbd_dev->dev_id < 0)
5383		goto fail_rbd_dev;
5384
5385	sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id);
5386	rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM,
5387						   rbd_dev->name);
5388	if (!rbd_dev->task_wq)
5389		goto fail_dev_id;
5390
5391	/* we have a ref from do_rbd_add() */
5392	__module_get(THIS_MODULE);
5393
5394	dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id);
5395	return rbd_dev;
5396
5397fail_dev_id:
5398	ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
5399fail_rbd_dev:
5400	rbd_dev_free(rbd_dev);
5401	return NULL;
5402}
5403
5404static void rbd_dev_destroy(struct rbd_device *rbd_dev)
5405{
5406	if (rbd_dev)
5407		put_device(&rbd_dev->dev);
5408}
5409
5410/*
5411 * Get the size and object order for an image snapshot, or if
5412 * snap_id is CEPH_NOSNAP, gets this information for the base
5413 * image.
5414 */
5415static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
5416				u8 *order, u64 *snap_size)
5417{
5418	__le64 snapid = cpu_to_le64(snap_id);
5419	int ret;
5420	struct {
5421		u8 order;
5422		__le64 size;
5423	} __attribute__ ((packed)) size_buf = { 0 };
5424
5425	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5426				  &rbd_dev->header_oloc, "get_size",
5427				  &snapid, sizeof(snapid),
5428				  &size_buf, sizeof(size_buf));
5429	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5430	if (ret < 0)
5431		return ret;
5432	if (ret < sizeof (size_buf))
5433		return -ERANGE;
5434
5435	if (order) {
5436		*order = size_buf.order;
5437		dout("  order %u", (unsigned int)*order);
5438	}
5439	*snap_size = le64_to_cpu(size_buf.size);
5440
5441	dout("  snap_id 0x%016llx snap_size = %llu\n",
5442		(unsigned long long)snap_id,
5443		(unsigned long long)*snap_size);
5444
5445	return 0;
5446}
5447
5448static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
5449{
5450	return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
5451					&rbd_dev->header.obj_order,
5452					&rbd_dev->header.image_size);
5453}
5454
5455static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
 
 
5456{
5457	size_t size;
5458	void *reply_buf;
5459	int ret;
5460	void *p;
5461
5462	/* Response will be an encoded string, which includes a length */
5463	size = sizeof(__le32) + RBD_OBJ_PREFIX_LEN_MAX;
5464	reply_buf = kzalloc(size, GFP_KERNEL);
5465	if (!reply_buf)
5466		return -ENOMEM;
5467
5468	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5469				  &rbd_dev->header_oloc, "get_object_prefix",
5470				  NULL, 0, reply_buf, size);
5471	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5472	if (ret < 0)
5473		goto out;
5474
5475	p = reply_buf;
5476	rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
5477						p + ret, NULL, GFP_NOIO);
5478	ret = 0;
5479
5480	if (IS_ERR(rbd_dev->header.object_prefix)) {
5481		ret = PTR_ERR(rbd_dev->header.object_prefix);
5482		rbd_dev->header.object_prefix = NULL;
5483	} else {
5484		dout("  object_prefix = %s\n", rbd_dev->header.object_prefix);
5485	}
5486out:
5487	kfree(reply_buf);
5488
 
 
5489	return ret;
5490}
5491
5492static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
5493				     bool read_only, u64 *snap_features)
5494{
5495	struct {
5496		__le64 snap_id;
5497		u8 read_only;
5498	} features_in;
5499	struct {
5500		__le64 features;
5501		__le64 incompat;
5502	} __attribute__ ((packed)) features_buf = { 0 };
5503	u64 unsup;
5504	int ret;
5505
5506	features_in.snap_id = cpu_to_le64(snap_id);
5507	features_in.read_only = read_only;
5508
5509	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5510				  &rbd_dev->header_oloc, "get_features",
5511				  &features_in, sizeof(features_in),
5512				  &features_buf, sizeof(features_buf));
5513	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5514	if (ret < 0)
5515		return ret;
5516	if (ret < sizeof (features_buf))
5517		return -ERANGE;
5518
5519	unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED;
5520	if (unsup) {
5521		rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx",
5522			 unsup);
5523		return -ENXIO;
5524	}
5525
5526	*snap_features = le64_to_cpu(features_buf.features);
5527
5528	dout("  snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
5529		(unsigned long long)snap_id,
5530		(unsigned long long)*snap_features,
5531		(unsigned long long)le64_to_cpu(features_buf.incompat));
5532
5533	return 0;
5534}
5535
5536static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
5537{
5538	return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
5539					 rbd_is_ro(rbd_dev),
5540					 &rbd_dev->header.features);
5541}
5542
5543/*
5544 * These are generic image flags, but since they are used only for
5545 * object map, store them in rbd_dev->object_map_flags.
5546 *
5547 * For the same reason, this function is called only on object map
5548 * (re)load and not on header refresh.
5549 */
5550static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev)
5551{
5552	__le64 snapid = cpu_to_le64(rbd_dev->spec->snap_id);
5553	__le64 flags;
5554	int ret;
5555
5556	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5557				  &rbd_dev->header_oloc, "get_flags",
5558				  &snapid, sizeof(snapid),
5559				  &flags, sizeof(flags));
5560	if (ret < 0)
5561		return ret;
5562	if (ret < sizeof(flags))
5563		return -EBADMSG;
5564
5565	rbd_dev->object_map_flags = le64_to_cpu(flags);
5566	return 0;
5567}
5568
5569struct parent_image_info {
5570	u64		pool_id;
5571	const char	*pool_ns;
5572	const char	*image_id;
5573	u64		snap_id;
5574
5575	bool		has_overlap;
5576	u64		overlap;
5577};
5578
5579/*
5580 * The caller is responsible for @pii.
5581 */
5582static int decode_parent_image_spec(void **p, void *end,
5583				    struct parent_image_info *pii)
5584{
5585	u8 struct_v;
5586	u32 struct_len;
5587	int ret;
5588
5589	ret = ceph_start_decoding(p, end, 1, "ParentImageSpec",
5590				  &struct_v, &struct_len);
5591	if (ret)
5592		return ret;
5593
5594	ceph_decode_64_safe(p, end, pii->pool_id, e_inval);
5595	pii->pool_ns = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5596	if (IS_ERR(pii->pool_ns)) {
5597		ret = PTR_ERR(pii->pool_ns);
5598		pii->pool_ns = NULL;
5599		return ret;
5600	}
5601	pii->image_id = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5602	if (IS_ERR(pii->image_id)) {
5603		ret = PTR_ERR(pii->image_id);
5604		pii->image_id = NULL;
5605		return ret;
5606	}
5607	ceph_decode_64_safe(p, end, pii->snap_id, e_inval);
5608	return 0;
5609
5610e_inval:
5611	return -EINVAL;
5612}
5613
5614static int __get_parent_info(struct rbd_device *rbd_dev,
5615			     struct page *req_page,
5616			     struct page *reply_page,
5617			     struct parent_image_info *pii)
5618{
5619	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5620	size_t reply_len = PAGE_SIZE;
5621	void *p, *end;
5622	int ret;
5623
5624	ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5625			     "rbd", "parent_get", CEPH_OSD_FLAG_READ,
5626			     req_page, sizeof(u64), &reply_page, &reply_len);
5627	if (ret)
5628		return ret == -EOPNOTSUPP ? 1 : ret;
5629
5630	p = page_address(reply_page);
5631	end = p + reply_len;
5632	ret = decode_parent_image_spec(&p, end, pii);
5633	if (ret)
5634		return ret;
5635
5636	ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5637			     "rbd", "parent_overlap_get", CEPH_OSD_FLAG_READ,
5638			     req_page, sizeof(u64), &reply_page, &reply_len);
5639	if (ret)
5640		return ret;
5641
5642	p = page_address(reply_page);
5643	end = p + reply_len;
5644	ceph_decode_8_safe(&p, end, pii->has_overlap, e_inval);
5645	if (pii->has_overlap)
5646		ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5647
5648	return 0;
5649
5650e_inval:
5651	return -EINVAL;
5652}
5653
5654/*
5655 * The caller is responsible for @pii.
 
 
 
 
 
5656 */
5657static int __get_parent_info_legacy(struct rbd_device *rbd_dev,
5658				    struct page *req_page,
5659				    struct page *reply_page,
5660				    struct parent_image_info *pii)
5661{
5662	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5663	size_t reply_len = PAGE_SIZE;
5664	void *p, *end;
5665	int ret;
 
5666
5667	ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5668			     "rbd", "get_parent", CEPH_OSD_FLAG_READ,
5669			     req_page, sizeof(u64), &reply_page, &reply_len);
5670	if (ret)
5671		return ret;
5672
5673	p = page_address(reply_page);
5674	end = p + reply_len;
5675	ceph_decode_64_safe(&p, end, pii->pool_id, e_inval);
5676	pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5677	if (IS_ERR(pii->image_id)) {
5678		ret = PTR_ERR(pii->image_id);
5679		pii->image_id = NULL;
5680		return ret;
5681	}
5682	ceph_decode_64_safe(&p, end, pii->snap_id, e_inval);
5683	pii->has_overlap = true;
5684	ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5685
5686	return 0;
5687
5688e_inval:
5689	return -EINVAL;
5690}
5691
5692static int get_parent_info(struct rbd_device *rbd_dev,
5693			   struct parent_image_info *pii)
5694{
5695	struct page *req_page, *reply_page;
5696	void *p;
5697	int ret;
5698
5699	req_page = alloc_page(GFP_KERNEL);
5700	if (!req_page)
5701		return -ENOMEM;
5702
5703	reply_page = alloc_page(GFP_KERNEL);
5704	if (!reply_page) {
5705		__free_page(req_page);
5706		return -ENOMEM;
5707	}
5708
5709	p = page_address(req_page);
5710	ceph_encode_64(&p, rbd_dev->spec->snap_id);
5711	ret = __get_parent_info(rbd_dev, req_page, reply_page, pii);
5712	if (ret > 0)
5713		ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page,
5714					       pii);
5715
5716	__free_page(req_page);
5717	__free_page(reply_page);
5718	return ret;
5719}
5720
5721static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
5722{
5723	struct rbd_spec *parent_spec;
5724	struct parent_image_info pii = { 0 };
5725	int ret;
5726
5727	parent_spec = rbd_spec_alloc();
5728	if (!parent_spec)
5729		return -ENOMEM;
5730
5731	ret = get_parent_info(rbd_dev, &pii);
5732	if (ret)
5733		goto out_err;
5734
5735	dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
5736	     __func__, pii.pool_id, pii.pool_ns, pii.image_id, pii.snap_id,
5737	     pii.has_overlap, pii.overlap);
5738
5739	if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap) {
5740		/*
5741		 * Either the parent never existed, or we have
5742		 * record of it but the image got flattened so it no
5743		 * longer has a parent.  When the parent of a
5744		 * layered image disappears we immediately set the
5745		 * overlap to 0.  The effect of this is that all new
5746		 * requests will be treated as if the image had no
5747		 * parent.
5748		 *
5749		 * If !pii.has_overlap, the parent image spec is not
5750		 * applicable.  It's there to avoid duplication in each
5751		 * snapshot record.
5752		 */
5753		if (rbd_dev->parent_overlap) {
5754			rbd_dev->parent_overlap = 0;
5755			rbd_dev_parent_put(rbd_dev);
5756			pr_info("%s: clone image has been flattened\n",
5757				rbd_dev->disk->disk_name);
5758		}
5759
5760		goto out;	/* No parent?  No problem. */
5761	}
5762
5763	/* The ceph file layout needs to fit pool id in 32 bits */
5764
5765	ret = -EIO;
5766	if (pii.pool_id > (u64)U32_MAX) {
5767		rbd_warn(NULL, "parent pool id too large (%llu > %u)",
5768			(unsigned long long)pii.pool_id, U32_MAX);
5769		goto out_err;
5770	}
5771
5772	/*
5773	 * The parent won't change (except when the clone is
5774	 * flattened, already handled that).  So we only need to
5775	 * record the parent spec we have not already done so.
5776	 */
5777	if (!rbd_dev->parent_spec) {
5778		parent_spec->pool_id = pii.pool_id;
5779		if (pii.pool_ns && *pii.pool_ns) {
5780			parent_spec->pool_ns = pii.pool_ns;
5781			pii.pool_ns = NULL;
5782		}
5783		parent_spec->image_id = pii.image_id;
5784		pii.image_id = NULL;
5785		parent_spec->snap_id = pii.snap_id;
5786
5787		rbd_dev->parent_spec = parent_spec;
5788		parent_spec = NULL;	/* rbd_dev now owns this */
5789	}
5790
5791	/*
5792	 * We always update the parent overlap.  If it's zero we issue
5793	 * a warning, as we will proceed as if there was no parent.
5794	 */
5795	if (!pii.overlap) {
5796		if (parent_spec) {
5797			/* refresh, careful to warn just once */
5798			if (rbd_dev->parent_overlap)
5799				rbd_warn(rbd_dev,
5800				    "clone now standalone (overlap became 0)");
5801		} else {
5802			/* initial probe */
5803			rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
5804		}
 
 
 
 
5805	}
5806	rbd_dev->parent_overlap = pii.overlap;
5807
5808out:
5809	ret = 0;
5810out_err:
5811	kfree(pii.pool_ns);
5812	kfree(pii.image_id);
5813	rbd_spec_put(parent_spec);
5814	return ret;
5815}
5816
5817static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
5818{
5819	struct {
5820		__le64 stripe_unit;
5821		__le64 stripe_count;
5822	} __attribute__ ((packed)) striping_info_buf = { 0 };
5823	size_t size = sizeof (striping_info_buf);
5824	void *p;
5825	int ret;
5826
5827	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5828				&rbd_dev->header_oloc, "get_stripe_unit_count",
5829				NULL, 0, &striping_info_buf, size);
5830	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5831	if (ret < 0)
5832		return ret;
5833	if (ret < size)
5834		return -ERANGE;
5835
5836	p = &striping_info_buf;
5837	rbd_dev->header.stripe_unit = ceph_decode_64(&p);
5838	rbd_dev->header.stripe_count = ceph_decode_64(&p);
5839	return 0;
5840}
5841
5842static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev)
5843{
5844	__le64 data_pool_id;
5845	int ret;
5846
5847	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5848				  &rbd_dev->header_oloc, "get_data_pool",
5849				  NULL, 0, &data_pool_id, sizeof(data_pool_id));
5850	if (ret < 0)
5851		return ret;
5852	if (ret < sizeof(data_pool_id))
5853		return -EBADMSG;
5854
5855	rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id);
5856	WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL);
5857	return 0;
5858}
5859
5860static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
5861{
5862	CEPH_DEFINE_OID_ONSTACK(oid);
5863	size_t image_id_size;
5864	char *image_id;
5865	void *p;
5866	void *end;
5867	size_t size;
5868	void *reply_buf = NULL;
5869	size_t len = 0;
5870	char *image_name = NULL;
5871	int ret;
5872
5873	rbd_assert(!rbd_dev->spec->image_name);
5874
5875	len = strlen(rbd_dev->spec->image_id);
5876	image_id_size = sizeof (__le32) + len;
5877	image_id = kmalloc(image_id_size, GFP_KERNEL);
5878	if (!image_id)
5879		return NULL;
5880
5881	p = image_id;
5882	end = image_id + image_id_size;
5883	ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
5884
5885	size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
5886	reply_buf = kmalloc(size, GFP_KERNEL);
5887	if (!reply_buf)
5888		goto out;
5889
5890	ceph_oid_printf(&oid, "%s", RBD_DIRECTORY);
5891	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
5892				  "dir_get_name", image_id, image_id_size,
5893				  reply_buf, size);
5894	if (ret < 0)
5895		goto out;
5896	p = reply_buf;
5897	end = reply_buf + ret;
5898
5899	image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
5900	if (IS_ERR(image_name))
5901		image_name = NULL;
5902	else
5903		dout("%s: name is %s len is %zd\n", __func__, image_name, len);
5904out:
5905	kfree(reply_buf);
5906	kfree(image_id);
5907
5908	return image_name;
5909}
5910
5911static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5912{
5913	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
5914	const char *snap_name;
5915	u32 which = 0;
5916
5917	/* Skip over names until we find the one we are looking for */
5918
5919	snap_name = rbd_dev->header.snap_names;
5920	while (which < snapc->num_snaps) {
5921		if (!strcmp(name, snap_name))
5922			return snapc->snaps[which];
5923		snap_name += strlen(snap_name) + 1;
5924		which++;
5925	}
5926	return CEPH_NOSNAP;
5927}
5928
5929static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5930{
5931	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
5932	u32 which;
5933	bool found = false;
5934	u64 snap_id;
5935
5936	for (which = 0; !found && which < snapc->num_snaps; which++) {
5937		const char *snap_name;
5938
5939		snap_id = snapc->snaps[which];
5940		snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
5941		if (IS_ERR(snap_name)) {
5942			/* ignore no-longer existing snapshots */
5943			if (PTR_ERR(snap_name) == -ENOENT)
5944				continue;
5945			else
5946				break;
5947		}
5948		found = !strcmp(name, snap_name);
5949		kfree(snap_name);
5950	}
5951	return found ? snap_id : CEPH_NOSNAP;
5952}
5953
5954/*
5955 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
5956 * no snapshot by that name is found, or if an error occurs.
5957 */
5958static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5959{
5960	if (rbd_dev->image_format == 1)
5961		return rbd_v1_snap_id_by_name(rbd_dev, name);
5962
5963	return rbd_v2_snap_id_by_name(rbd_dev, name);
5964}
5965
5966/*
5967 * An image being mapped will have everything but the snap id.
5968 */
5969static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
5970{
5971	struct rbd_spec *spec = rbd_dev->spec;
5972
5973	rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
5974	rbd_assert(spec->image_id && spec->image_name);
5975	rbd_assert(spec->snap_name);
5976
5977	if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
5978		u64 snap_id;
5979
5980		snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
5981		if (snap_id == CEPH_NOSNAP)
5982			return -ENOENT;
5983
5984		spec->snap_id = snap_id;
5985	} else {
5986		spec->snap_id = CEPH_NOSNAP;
5987	}
5988
 
5989	return 0;
5990}
5991
5992/*
5993 * A parent image will have all ids but none of the names.
5994 *
5995 * All names in an rbd spec are dynamically allocated.  It's OK if we
5996 * can't figure out the name for an image id.
5997 */
5998static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
5999{
6000	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
6001	struct rbd_spec *spec = rbd_dev->spec;
6002	const char *pool_name;
6003	const char *image_name;
6004	const char *snap_name;
6005	int ret;
6006
6007	rbd_assert(spec->pool_id != CEPH_NOPOOL);
6008	rbd_assert(spec->image_id);
6009	rbd_assert(spec->snap_id != CEPH_NOSNAP);
6010
6011	/* Get the pool name; we have to make our own copy of this */
6012
6013	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
6014	if (!pool_name) {
6015		rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
6016		return -EIO;
6017	}
6018	pool_name = kstrdup(pool_name, GFP_KERNEL);
6019	if (!pool_name)
6020		return -ENOMEM;
6021
6022	/* Fetch the image name; tolerate failure here */
6023
6024	image_name = rbd_dev_image_name(rbd_dev);
6025	if (!image_name)
6026		rbd_warn(rbd_dev, "unable to get image name");
6027
6028	/* Fetch the snapshot name */
6029
6030	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
6031	if (IS_ERR(snap_name)) {
6032		ret = PTR_ERR(snap_name);
6033		goto out_err;
6034	}
6035
6036	spec->pool_name = pool_name;
6037	spec->image_name = image_name;
6038	spec->snap_name = snap_name;
6039
6040	return 0;
6041
6042out_err:
6043	kfree(image_name);
6044	kfree(pool_name);
6045	return ret;
6046}
6047
6048static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
6049{
6050	size_t size;
6051	int ret;
6052	void *reply_buf;
6053	void *p;
6054	void *end;
6055	u64 seq;
6056	u32 snap_count;
6057	struct ceph_snap_context *snapc;
6058	u32 i;
6059
6060	/*
6061	 * We'll need room for the seq value (maximum snapshot id),
6062	 * snapshot count, and array of that many snapshot ids.
6063	 * For now we have a fixed upper limit on the number we're
6064	 * prepared to receive.
6065	 */
6066	size = sizeof (__le64) + sizeof (__le32) +
6067			RBD_MAX_SNAP_COUNT * sizeof (__le64);
6068	reply_buf = kzalloc(size, GFP_KERNEL);
6069	if (!reply_buf)
6070		return -ENOMEM;
6071
6072	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6073				  &rbd_dev->header_oloc, "get_snapcontext",
6074				  NULL, 0, reply_buf, size);
6075	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6076	if (ret < 0)
6077		goto out;
6078
6079	p = reply_buf;
6080	end = reply_buf + ret;
6081	ret = -ERANGE;
6082	ceph_decode_64_safe(&p, end, seq, out);
6083	ceph_decode_32_safe(&p, end, snap_count, out);
6084
6085	/*
6086	 * Make sure the reported number of snapshot ids wouldn't go
6087	 * beyond the end of our buffer.  But before checking that,
6088	 * make sure the computed size of the snapshot context we
6089	 * allocate is representable in a size_t.
6090	 */
6091	if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
6092				 / sizeof (u64)) {
6093		ret = -EINVAL;
6094		goto out;
6095	}
6096	if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
6097		goto out;
6098	ret = 0;
6099
6100	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
6101	if (!snapc) {
6102		ret = -ENOMEM;
6103		goto out;
6104	}
6105	snapc->seq = seq;
6106	for (i = 0; i < snap_count; i++)
6107		snapc->snaps[i] = ceph_decode_64(&p);
6108
6109	ceph_put_snap_context(rbd_dev->header.snapc);
6110	rbd_dev->header.snapc = snapc;
6111
6112	dout("  snap context seq = %llu, snap_count = %u\n",
6113		(unsigned long long)seq, (unsigned int)snap_count);
6114out:
6115	kfree(reply_buf);
6116
6117	return ret;
6118}
6119
6120static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
6121					u64 snap_id)
6122{
6123	size_t size;
6124	void *reply_buf;
6125	__le64 snapid;
6126	int ret;
6127	void *p;
6128	void *end;
6129	char *snap_name;
6130
6131	size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
6132	reply_buf = kmalloc(size, GFP_KERNEL);
6133	if (!reply_buf)
6134		return ERR_PTR(-ENOMEM);
6135
6136	snapid = cpu_to_le64(snap_id);
6137	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6138				  &rbd_dev->header_oloc, "get_snapshot_name",
6139				  &snapid, sizeof(snapid), reply_buf, size);
6140	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6141	if (ret < 0) {
6142		snap_name = ERR_PTR(ret);
6143		goto out;
6144	}
6145
6146	p = reply_buf;
6147	end = reply_buf + ret;
6148	snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
6149	if (IS_ERR(snap_name))
6150		goto out;
6151
6152	dout("  snap_id 0x%016llx snap_name = %s\n",
6153		(unsigned long long)snap_id, snap_name);
6154out:
6155	kfree(reply_buf);
6156
6157	return snap_name;
6158}
6159
6160static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
6161{
6162	bool first_time = rbd_dev->header.object_prefix == NULL;
6163	int ret;
6164
6165	ret = rbd_dev_v2_image_size(rbd_dev);
6166	if (ret)
6167		return ret;
6168
6169	if (first_time) {
6170		ret = rbd_dev_v2_header_onetime(rbd_dev);
6171		if (ret)
6172			return ret;
6173	}
6174
6175	ret = rbd_dev_v2_snap_context(rbd_dev);
6176	if (ret && first_time) {
6177		kfree(rbd_dev->header.object_prefix);
6178		rbd_dev->header.object_prefix = NULL;
6179	}
6180
6181	return ret;
6182}
6183
6184static int rbd_dev_header_info(struct rbd_device *rbd_dev)
 
 
6185{
6186	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
 
 
 
 
 
 
6187
6188	if (rbd_dev->image_format == 1)
6189		return rbd_dev_v1_header_info(rbd_dev);
6190
6191	return rbd_dev_v2_header_info(rbd_dev);
6192}
 
6193
6194/*
6195 * Skips over white space at *buf, and updates *buf to point to the
6196 * first found non-space character (if any). Returns the length of
6197 * the token (string of non-white space characters) found.  Note
6198 * that *buf must be terminated with '\0'.
6199 */
6200static inline size_t next_token(const char **buf)
6201{
6202        /*
6203        * These are the characters that produce nonzero for
6204        * isspace() in the "C" and "POSIX" locales.
6205        */
6206        const char *spaces = " \f\n\r\t\v";
6207
6208        *buf += strspn(*buf, spaces);	/* Find start of token */
 
 
 
6209
6210	return strcspn(*buf, spaces);   /* Return token length */
6211}
 
 
6212
6213/*
6214 * Finds the next token in *buf, dynamically allocates a buffer big
6215 * enough to hold a copy of it, and copies the token into the new
6216 * buffer.  The copy is guaranteed to be terminated with '\0'.  Note
6217 * that a duplicate buffer is created even for a zero-length token.
6218 *
6219 * Returns a pointer to the newly-allocated duplicate, or a null
6220 * pointer if memory for the duplicate was not available.  If
6221 * the lenp argument is a non-null pointer, the length of the token
6222 * (not including the '\0') is returned in *lenp.
6223 *
6224 * If successful, the *buf pointer will be updated to point beyond
6225 * the end of the found token.
6226 *
6227 * Note: uses GFP_KERNEL for allocation.
6228 */
6229static inline char *dup_token(const char **buf, size_t *lenp)
6230{
6231	char *dup;
6232	size_t len;
6233
6234	len = next_token(buf);
6235	dup = kmemdup(*buf, len + 1, GFP_KERNEL);
6236	if (!dup)
6237		return NULL;
6238	*(dup + len) = '\0';
6239	*buf += len;
6240
6241	if (lenp)
6242		*lenp = len;
6243
6244	return dup;
6245}
6246
6247static int rbd_parse_param(struct fs_parameter *param,
6248			    struct rbd_parse_opts_ctx *pctx)
6249{
6250	struct rbd_options *opt = pctx->opts;
6251	struct fs_parse_result result;
6252	struct p_log log = {.prefix = "rbd"};
6253	int token, ret;
6254
6255	ret = ceph_parse_param(param, pctx->copts, NULL);
6256	if (ret != -ENOPARAM)
6257		return ret;
6258
6259	token = __fs_parse(&log, rbd_parameters, param, &result);
6260	dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
6261	if (token < 0) {
6262		if (token == -ENOPARAM)
6263			return inval_plog(&log, "Unknown parameter '%s'",
6264					  param->key);
6265		return token;
6266	}
6267
6268	switch (token) {
6269	case Opt_queue_depth:
6270		if (result.uint_32 < 1)
6271			goto out_of_range;
6272		opt->queue_depth = result.uint_32;
6273		break;
6274	case Opt_alloc_size:
6275		if (result.uint_32 < SECTOR_SIZE)
6276			goto out_of_range;
6277		if (!is_power_of_2(result.uint_32))
6278			return inval_plog(&log, "alloc_size must be a power of 2");
6279		opt->alloc_size = result.uint_32;
6280		break;
6281	case Opt_lock_timeout:
6282		/* 0 is "wait forever" (i.e. infinite timeout) */
6283		if (result.uint_32 > INT_MAX / 1000)
6284			goto out_of_range;
6285		opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
6286		break;
6287	case Opt_pool_ns:
6288		kfree(pctx->spec->pool_ns);
6289		pctx->spec->pool_ns = param->string;
6290		param->string = NULL;
6291		break;
6292	case Opt_compression_hint:
6293		switch (result.uint_32) {
6294		case Opt_compression_hint_none:
6295			opt->alloc_hint_flags &=
6296			    ~(CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE |
6297			      CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE);
6298			break;
6299		case Opt_compression_hint_compressible:
6300			opt->alloc_hint_flags |=
6301			    CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6302			opt->alloc_hint_flags &=
6303			    ~CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6304			break;
6305		case Opt_compression_hint_incompressible:
6306			opt->alloc_hint_flags |=
6307			    CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6308			opt->alloc_hint_flags &=
6309			    ~CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6310			break;
6311		default:
6312			BUG();
6313		}
6314		break;
6315	case Opt_read_only:
6316		opt->read_only = true;
6317		break;
6318	case Opt_read_write:
6319		opt->read_only = false;
6320		break;
6321	case Opt_lock_on_read:
6322		opt->lock_on_read = true;
6323		break;
6324	case Opt_exclusive:
6325		opt->exclusive = true;
6326		break;
6327	case Opt_notrim:
6328		opt->trim = false;
6329		break;
6330	default:
6331		BUG();
6332	}
6333
6334	return 0;
 
6335
6336out_of_range:
6337	return inval_plog(&log, "%s out of range", param->key);
6338}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6339
6340/*
6341 * This duplicates most of generic_parse_monolithic(), untying it from
6342 * fs_context and skipping standard superblock and security options.
6343 */
6344static int rbd_parse_options(char *options, struct rbd_parse_opts_ctx *pctx)
6345{
6346	char *key;
6347	int ret = 0;
6348
6349	dout("%s '%s'\n", __func__, options);
6350	while ((key = strsep(&options, ",")) != NULL) {
6351		if (*key) {
6352			struct fs_parameter param = {
6353				.key	= key,
6354				.type	= fs_value_is_flag,
6355			};
6356			char *value = strchr(key, '=');
6357			size_t v_len = 0;
6358
6359			if (value) {
6360				if (value == key)
6361					continue;
6362				*value++ = 0;
6363				v_len = strlen(value);
6364				param.string = kmemdup_nul(value, v_len,
6365							   GFP_KERNEL);
6366				if (!param.string)
6367					return -ENOMEM;
6368				param.type = fs_value_is_string;
6369			}
6370			param.size = v_len;
6371
6372			ret = rbd_parse_param(&param, pctx);
6373			kfree(param.string);
6374			if (ret)
6375				break;
6376		}
6377	}
6378
6379	return ret;
6380}
6381
6382/*
6383 * Parse the options provided for an "rbd add" (i.e., rbd image
6384 * mapping) request.  These arrive via a write to /sys/bus/rbd/add,
6385 * and the data written is passed here via a NUL-terminated buffer.
6386 * Returns 0 if successful or an error code otherwise.
6387 *
6388 * The information extracted from these options is recorded in
6389 * the other parameters which return dynamically-allocated
6390 * structures:
6391 *  ceph_opts
6392 *      The address of a pointer that will refer to a ceph options
6393 *      structure.  Caller must release the returned pointer using
6394 *      ceph_destroy_options() when it is no longer needed.
6395 *  rbd_opts
6396 *	Address of an rbd options pointer.  Fully initialized by
6397 *	this function; caller must release with kfree().
6398 *  spec
6399 *	Address of an rbd image specification pointer.  Fully
6400 *	initialized by this function based on parsed options.
6401 *	Caller must release with rbd_spec_put().
6402 *
6403 * The options passed take this form:
6404 *  <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
6405 * where:
6406 *  <mon_addrs>
6407 *      A comma-separated list of one or more monitor addresses.
6408 *      A monitor address is an ip address, optionally followed
6409 *      by a port number (separated by a colon).
6410 *        I.e.:  ip1[:port1][,ip2[:port2]...]
6411 *  <options>
6412 *      A comma-separated list of ceph and/or rbd options.
6413 *  <pool_name>
6414 *      The name of the rados pool containing the rbd image.
6415 *  <image_name>
6416 *      The name of the image in that pool to map.
6417 *  <snap_id>
6418 *      An optional snapshot id.  If provided, the mapping will
6419 *      present data from the image at the time that snapshot was
6420 *      created.  The image head is used if no snapshot id is
6421 *      provided.  Snapshot mappings are always read-only.
6422 */
6423static int rbd_add_parse_args(const char *buf,
6424				struct ceph_options **ceph_opts,
6425				struct rbd_options **opts,
6426				struct rbd_spec **rbd_spec)
6427{
6428	size_t len;
6429	char *options;
6430	const char *mon_addrs;
6431	char *snap_name;
6432	size_t mon_addrs_size;
6433	struct rbd_parse_opts_ctx pctx = { 0 };
6434	int ret;
6435
6436	/* The first four tokens are required */
6437
6438	len = next_token(&buf);
6439	if (!len) {
6440		rbd_warn(NULL, "no monitor address(es) provided");
6441		return -EINVAL;
6442	}
6443	mon_addrs = buf;
6444	mon_addrs_size = len;
6445	buf += len;
6446
6447	ret = -EINVAL;
6448	options = dup_token(&buf, NULL);
6449	if (!options)
6450		return -ENOMEM;
6451	if (!*options) {
6452		rbd_warn(NULL, "no options provided");
6453		goto out_err;
6454	}
6455
6456	pctx.spec = rbd_spec_alloc();
6457	if (!pctx.spec)
6458		goto out_mem;
6459
6460	pctx.spec->pool_name = dup_token(&buf, NULL);
6461	if (!pctx.spec->pool_name)
6462		goto out_mem;
6463	if (!*pctx.spec->pool_name) {
6464		rbd_warn(NULL, "no pool name provided");
6465		goto out_err;
6466	}
6467
6468	pctx.spec->image_name = dup_token(&buf, NULL);
6469	if (!pctx.spec->image_name)
6470		goto out_mem;
6471	if (!*pctx.spec->image_name) {
6472		rbd_warn(NULL, "no image name provided");
6473		goto out_err;
6474	}
6475
6476	/*
6477	 * Snapshot name is optional; default is to use "-"
6478	 * (indicating the head/no snapshot).
6479	 */
6480	len = next_token(&buf);
6481	if (!len) {
6482		buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
6483		len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
6484	} else if (len > RBD_MAX_SNAP_NAME_LEN) {
6485		ret = -ENAMETOOLONG;
6486		goto out_err;
6487	}
6488	snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
6489	if (!snap_name)
6490		goto out_mem;
6491	*(snap_name + len) = '\0';
6492	pctx.spec->snap_name = snap_name;
6493
6494	pctx.copts = ceph_alloc_options();
6495	if (!pctx.copts)
6496		goto out_mem;
6497
6498	/* Initialize all rbd options to the defaults */
6499
6500	pctx.opts = kzalloc(sizeof(*pctx.opts), GFP_KERNEL);
6501	if (!pctx.opts)
6502		goto out_mem;
6503
6504	pctx.opts->read_only = RBD_READ_ONLY_DEFAULT;
6505	pctx.opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
6506	pctx.opts->alloc_size = RBD_ALLOC_SIZE_DEFAULT;
6507	pctx.opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT;
6508	pctx.opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT;
6509	pctx.opts->exclusive = RBD_EXCLUSIVE_DEFAULT;
6510	pctx.opts->trim = RBD_TRIM_DEFAULT;
6511
6512	ret = ceph_parse_mon_ips(mon_addrs, mon_addrs_size, pctx.copts, NULL);
6513	if (ret)
6514		goto out_err;
 
6515
6516	ret = rbd_parse_options(options, &pctx);
6517	if (ret)
6518		goto out_err;
6519
6520	*ceph_opts = pctx.copts;
6521	*opts = pctx.opts;
6522	*rbd_spec = pctx.spec;
6523	kfree(options);
6524	return 0;
 
 
 
 
 
 
 
 
 
 
6525
6526out_mem:
6527	ret = -ENOMEM;
6528out_err:
6529	kfree(pctx.opts);
6530	ceph_destroy_options(pctx.copts);
6531	rbd_spec_put(pctx.spec);
6532	kfree(options);
6533	return ret;
 
 
 
 
 
6534}
6535
6536static void rbd_dev_image_unlock(struct rbd_device *rbd_dev)
6537{
6538	down_write(&rbd_dev->lock_rwsem);
6539	if (__rbd_is_lock_owner(rbd_dev))
6540		__rbd_release_lock(rbd_dev);
6541	up_write(&rbd_dev->lock_rwsem);
6542}
6543
6544/*
6545 * If the wait is interrupted, an error is returned even if the lock
6546 * was successfully acquired.  rbd_dev_image_unlock() will release it
6547 * if needed.
6548 */
6549static int rbd_add_acquire_lock(struct rbd_device *rbd_dev)
6550{
6551	long ret;
6552
6553	if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) {
6554		if (!rbd_dev->opts->exclusive && !rbd_dev->opts->lock_on_read)
6555			return 0;
6556
6557		rbd_warn(rbd_dev, "exclusive-lock feature is not enabled");
6558		return -EINVAL;
6559	}
6560
6561	if (rbd_is_ro(rbd_dev))
6562		return 0;
6563
6564	rbd_assert(!rbd_is_lock_owner(rbd_dev));
6565	queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
6566	ret = wait_for_completion_killable_timeout(&rbd_dev->acquire_wait,
6567			    ceph_timeout_jiffies(rbd_dev->opts->lock_timeout));
6568	if (ret > 0) {
6569		ret = rbd_dev->acquire_err;
6570	} else {
6571		cancel_delayed_work_sync(&rbd_dev->lock_dwork);
6572		if (!ret)
6573			ret = -ETIMEDOUT;
6574	}
6575
6576	if (ret) {
6577		rbd_warn(rbd_dev, "failed to acquire exclusive lock: %ld", ret);
6578		return ret;
6579	}
6580
6581	/*
6582	 * The lock may have been released by now, unless automatic lock
6583	 * transitions are disabled.
6584	 */
6585	rbd_assert(!rbd_dev->opts->exclusive || rbd_is_lock_owner(rbd_dev));
6586	return 0;
6587}
6588
6589/*
6590 * An rbd format 2 image has a unique identifier, distinct from the
6591 * name given to it by the user.  Internally, that identifier is
6592 * what's used to specify the names of objects related to the image.
6593 *
6594 * A special "rbd id" object is used to map an rbd image name to its
6595 * id.  If that object doesn't exist, then there is no v2 rbd image
6596 * with the supplied name.
6597 *
6598 * This function will record the given rbd_dev's image_id field if
6599 * it can be determined, and in that case will return 0.  If any
6600 * errors occur a negative errno will be returned and the rbd_dev's
6601 * image_id field will be unchanged (and should be NULL).
6602 */
6603static int rbd_dev_image_id(struct rbd_device *rbd_dev)
6604{
6605	int ret;
6606	size_t size;
6607	CEPH_DEFINE_OID_ONSTACK(oid);
6608	void *response;
6609	char *image_id;
6610
6611	/*
6612	 * When probing a parent image, the image id is already
6613	 * known (and the image name likely is not).  There's no
6614	 * need to fetch the image id again in this case.  We
6615	 * do still need to set the image format though.
6616	 */
6617	if (rbd_dev->spec->image_id) {
6618		rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
6619
6620		return 0;
6621	}
6622
6623	/*
6624	 * First, see if the format 2 image id file exists, and if
6625	 * so, get the image's persistent id from it.
6626	 */
6627	ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX,
6628			       rbd_dev->spec->image_name);
6629	if (ret)
6630		return ret;
6631
6632	dout("rbd id object name is %s\n", oid.name);
6633
6634	/* Response will be an encoded string, which includes a length */
6635	size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
6636	response = kzalloc(size, GFP_NOIO);
6637	if (!response) {
6638		ret = -ENOMEM;
6639		goto out;
6640	}
6641
6642	/* If it doesn't exist we'll assume it's a format 1 image */
6643
6644	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
6645				  "get_id", NULL, 0,
6646				  response, size);
6647	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6648	if (ret == -ENOENT) {
6649		image_id = kstrdup("", GFP_KERNEL);
6650		ret = image_id ? 0 : -ENOMEM;
6651		if (!ret)
6652			rbd_dev->image_format = 1;
6653	} else if (ret >= 0) {
6654		void *p = response;
6655
6656		image_id = ceph_extract_encoded_string(&p, p + ret,
6657						NULL, GFP_NOIO);
6658		ret = PTR_ERR_OR_ZERO(image_id);
6659		if (!ret)
6660			rbd_dev->image_format = 2;
6661	}
6662
6663	if (!ret) {
6664		rbd_dev->spec->image_id = image_id;
6665		dout("image_id is %s\n", image_id);
6666	}
6667out:
6668	kfree(response);
6669	ceph_oid_destroy(&oid);
6670	return ret;
6671}
6672
6673/*
6674 * Undo whatever state changes are made by v1 or v2 header info
6675 * call.
6676 */
6677static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
6678{
6679	struct rbd_image_header	*header;
 
 
 
6680
6681	rbd_dev_parent_put(rbd_dev);
6682	rbd_object_map_free(rbd_dev);
6683	rbd_dev_mapping_clear(rbd_dev);
6684
6685	/* Free dynamic fields from the header, then zero it out */
6686
6687	header = &rbd_dev->header;
6688	ceph_put_snap_context(header->snapc);
6689	kfree(header->snap_sizes);
6690	kfree(header->snap_names);
6691	kfree(header->object_prefix);
6692	memset(header, 0, sizeof (*header));
6693}
6694
6695static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
6696{
6697	int ret;
6698
6699	ret = rbd_dev_v2_object_prefix(rbd_dev);
6700	if (ret)
6701		goto out_err;
6702
6703	/*
6704	 * Get the and check features for the image.  Currently the
6705	 * features are assumed to never change.
6706	 */
6707	ret = rbd_dev_v2_features(rbd_dev);
6708	if (ret)
6709		goto out_err;
6710
6711	/* If the image supports fancy striping, get its parameters */
6712
6713	if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
6714		ret = rbd_dev_v2_striping_info(rbd_dev);
6715		if (ret < 0)
6716			goto out_err;
6717	}
6718
6719	if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) {
6720		ret = rbd_dev_v2_data_pool(rbd_dev);
6721		if (ret)
6722			goto out_err;
6723	}
6724
6725	rbd_init_layout(rbd_dev);
6726	return 0;
6727
6728out_err:
6729	rbd_dev->header.features = 0;
6730	kfree(rbd_dev->header.object_prefix);
6731	rbd_dev->header.object_prefix = NULL;
6732	return ret;
6733}
6734
6735/*
6736 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() ->
6737 * rbd_dev_image_probe() recursion depth, which means it's also the
6738 * length of the already discovered part of the parent chain.
6739 */
6740static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth)
6741{
6742	struct rbd_device *parent = NULL;
6743	int ret;
 
 
 
6744
6745	if (!rbd_dev->parent_spec)
6746		return 0;
6747
6748	if (++depth > RBD_MAX_PARENT_CHAIN_LEN) {
6749		pr_info("parent chain is too long (%d)\n", depth);
6750		ret = -EINVAL;
6751		goto out_err;
6752	}
6753
6754	parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec);
6755	if (!parent) {
6756		ret = -ENOMEM;
6757		goto out_err;
6758	}
6759
6760	/*
6761	 * Images related by parent/child relationships always share
6762	 * rbd_client and spec/parent_spec, so bump their refcounts.
6763	 */
6764	__rbd_get_client(rbd_dev->rbd_client);
6765	rbd_spec_get(rbd_dev->parent_spec);
6766
6767	__set_bit(RBD_DEV_FLAG_READONLY, &parent->flags);
6768
6769	ret = rbd_dev_image_probe(parent, depth);
6770	if (ret < 0)
6771		goto out_err;
6772
6773	rbd_dev->parent = parent;
6774	atomic_set(&rbd_dev->parent_ref, 1);
6775	return 0;
6776
6777out_err:
6778	rbd_dev_unparent(rbd_dev);
6779	rbd_dev_destroy(parent);
6780	return ret;
6781}
6782
6783static void rbd_dev_device_release(struct rbd_device *rbd_dev)
6784{
6785	clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6786	rbd_free_disk(rbd_dev);
6787	if (!single_major)
6788		unregister_blkdev(rbd_dev->major, rbd_dev->name);
6789}
6790
6791/*
6792 * rbd_dev->header_rwsem must be locked for write and will be unlocked
6793 * upon return.
6794 */
6795static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
6796{
6797	int ret;
6798
6799	/* Record our major and minor device numbers. */
 
 
6800
6801	if (!single_major) {
6802		ret = register_blkdev(0, rbd_dev->name);
6803		if (ret < 0)
6804			goto err_out_unlock;
6805
6806		rbd_dev->major = ret;
6807		rbd_dev->minor = 0;
6808	} else {
6809		rbd_dev->major = rbd_major;
6810		rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
6811	}
6812
6813	/* Set up the blkdev mapping. */
6814
6815	ret = rbd_init_disk(rbd_dev);
6816	if (ret)
6817		goto err_out_blkdev;
6818
6819	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
6820	set_disk_ro(rbd_dev->disk, rbd_is_ro(rbd_dev));
6821
6822	ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id);
6823	if (ret)
6824		goto err_out_disk;
6825
6826	set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6827	up_write(&rbd_dev->header_rwsem);
6828	return 0;
6829
6830err_out_disk:
6831	rbd_free_disk(rbd_dev);
6832err_out_blkdev:
6833	if (!single_major)
6834		unregister_blkdev(rbd_dev->major, rbd_dev->name);
6835err_out_unlock:
6836	up_write(&rbd_dev->header_rwsem);
6837	return ret;
6838}
6839
6840static int rbd_dev_header_name(struct rbd_device *rbd_dev)
6841{
6842	struct rbd_spec *spec = rbd_dev->spec;
6843	int ret;
6844
6845	/* Record the header object name for this rbd image. */
6846
6847	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6848	if (rbd_dev->image_format == 1)
6849		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6850				       spec->image_name, RBD_SUFFIX);
6851	else
6852		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6853				       RBD_HEADER_PREFIX, spec->image_id);
6854
 
 
 
6855	return ret;
6856}
6857
6858static void rbd_print_dne(struct rbd_device *rbd_dev, bool is_snap)
6859{
6860	if (!is_snap) {
6861		pr_info("image %s/%s%s%s does not exist\n",
6862			rbd_dev->spec->pool_name,
6863			rbd_dev->spec->pool_ns ?: "",
6864			rbd_dev->spec->pool_ns ? "/" : "",
6865			rbd_dev->spec->image_name);
6866	} else {
6867		pr_info("snap %s/%s%s%s@%s does not exist\n",
6868			rbd_dev->spec->pool_name,
6869			rbd_dev->spec->pool_ns ?: "",
6870			rbd_dev->spec->pool_ns ? "/" : "",
6871			rbd_dev->spec->image_name,
6872			rbd_dev->spec->snap_name);
6873	}
6874}
6875
6876static void rbd_dev_image_release(struct rbd_device *rbd_dev)
6877{
6878	if (!rbd_is_ro(rbd_dev))
6879		rbd_unregister_watch(rbd_dev);
6880
6881	rbd_dev_unprobe(rbd_dev);
6882	rbd_dev->image_format = 0;
6883	kfree(rbd_dev->spec->image_id);
6884	rbd_dev->spec->image_id = NULL;
6885}
6886
6887/*
6888 * Probe for the existence of the header object for the given rbd
6889 * device.  If this image is the one being mapped (i.e., not a
6890 * parent), initiate a watch on its header object before using that
6891 * object to get detailed information about the rbd image.
6892 *
6893 * On success, returns with header_rwsem held for write if called
6894 * with @depth == 0.
6895 */
6896static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
6897{
6898	bool need_watch = !rbd_is_ro(rbd_dev);
6899	int ret;
 
 
 
 
 
 
 
6900
6901	/*
6902	 * Get the id from the image id object.  Unless there's an
6903	 * error, rbd_dev->spec->image_id will be filled in with
6904	 * a dynamically-allocated string, and rbd_dev->image_format
6905	 * will be set to either 1 or 2.
6906	 */
6907	ret = rbd_dev_image_id(rbd_dev);
6908	if (ret)
6909		return ret;
6910
6911	ret = rbd_dev_header_name(rbd_dev);
6912	if (ret)
6913		goto err_out_format;
6914
6915	if (need_watch) {
6916		ret = rbd_register_watch(rbd_dev);
6917		if (ret) {
6918			if (ret == -ENOENT)
6919				rbd_print_dne(rbd_dev, false);
6920			goto err_out_format;
6921		}
6922	}
6923
6924	if (!depth)
6925		down_write(&rbd_dev->header_rwsem);
 
6926
6927	ret = rbd_dev_header_info(rbd_dev);
6928	if (ret) {
6929		if (ret == -ENOENT && !need_watch)
6930			rbd_print_dne(rbd_dev, false);
6931		goto err_out_probe;
6932	}
6933
6934	/*
6935	 * If this image is the one being mapped, we have pool name and
6936	 * id, image name and id, and snap name - need to fill snap id.
6937	 * Otherwise this is a parent image, identified by pool, image
6938	 * and snap ids - need to fill in names for those ids.
6939	 */
6940	if (!depth)
6941		ret = rbd_spec_fill_snap_id(rbd_dev);
6942	else
6943		ret = rbd_spec_fill_names(rbd_dev);
6944	if (ret) {
6945		if (ret == -ENOENT)
6946			rbd_print_dne(rbd_dev, true);
6947		goto err_out_probe;
6948	}
6949
6950	ret = rbd_dev_mapping_set(rbd_dev);
6951	if (ret)
6952		goto err_out_probe;
6953
6954	if (rbd_is_snap(rbd_dev) &&
6955	    (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) {
6956		ret = rbd_object_map_load(rbd_dev);
6957		if (ret)
6958			goto err_out_probe;
6959	}
6960
6961	if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
6962		ret = rbd_dev_v2_parent_info(rbd_dev);
6963		if (ret)
6964			goto err_out_probe;
6965	}
6966
6967	ret = rbd_dev_probe_parent(rbd_dev, depth);
6968	if (ret)
6969		goto err_out_probe;
6970
6971	dout("discovered format %u image, header name is %s\n",
6972		rbd_dev->image_format, rbd_dev->header_oid.name);
6973	return 0;
 
 
6974
6975err_out_probe:
6976	if (!depth)
6977		up_write(&rbd_dev->header_rwsem);
6978	if (need_watch)
6979		rbd_unregister_watch(rbd_dev);
6980	rbd_dev_unprobe(rbd_dev);
6981err_out_format:
6982	rbd_dev->image_format = 0;
6983	kfree(rbd_dev->spec->image_id);
6984	rbd_dev->spec->image_id = NULL;
6985	return ret;
6986}
6987
6988static ssize_t do_rbd_add(struct bus_type *bus,
6989			  const char *buf,
6990			  size_t count)
6991{
6992	struct rbd_device *rbd_dev = NULL;
6993	struct ceph_options *ceph_opts = NULL;
6994	struct rbd_options *rbd_opts = NULL;
6995	struct rbd_spec *spec = NULL;
6996	struct rbd_client *rbdc;
6997	int rc;
6998
6999	if (!capable(CAP_SYS_ADMIN))
7000		return -EPERM;
7001
7002	if (!try_module_get(THIS_MODULE))
7003		return -ENODEV;
7004
7005	/* parse add command */
7006	rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
7007	if (rc < 0)
7008		goto out;
7009
7010	rbdc = rbd_get_client(ceph_opts);
7011	if (IS_ERR(rbdc)) {
7012		rc = PTR_ERR(rbdc);
7013		goto err_out_args;
7014	}
7015
7016	/* pick the pool */
7017	rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name);
7018	if (rc < 0) {
7019		if (rc == -ENOENT)
7020			pr_info("pool %s does not exist\n", spec->pool_name);
7021		goto err_out_client;
7022	}
7023	spec->pool_id = (u64)rc;
7024
7025	rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
7026	if (!rbd_dev) {
7027		rc = -ENOMEM;
7028		goto err_out_client;
7029	}
7030	rbdc = NULL;		/* rbd_dev now owns this */
7031	spec = NULL;		/* rbd_dev now owns this */
7032	rbd_opts = NULL;	/* rbd_dev now owns this */
7033
7034	/* if we are mapping a snapshot it will be a read-only mapping */
7035	if (rbd_dev->opts->read_only ||
7036	    strcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME))
7037		__set_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags);
7038
7039	rbd_dev->config_info = kstrdup(buf, GFP_KERNEL);
7040	if (!rbd_dev->config_info) {
7041		rc = -ENOMEM;
7042		goto err_out_rbd_dev;
7043	}
7044
7045	rc = rbd_dev_image_probe(rbd_dev, 0);
7046	if (rc < 0)
7047		goto err_out_rbd_dev;
7048
7049	if (rbd_dev->opts->alloc_size > rbd_dev->layout.object_size) {
7050		rbd_warn(rbd_dev, "alloc_size adjusted to %u",
7051			 rbd_dev->layout.object_size);
7052		rbd_dev->opts->alloc_size = rbd_dev->layout.object_size;
7053	}
7054
7055	rc = rbd_dev_device_setup(rbd_dev);
7056	if (rc)
7057		goto err_out_image_probe;
7058
7059	rc = rbd_add_acquire_lock(rbd_dev);
7060	if (rc)
7061		goto err_out_image_lock;
7062
7063	/* Everything's ready.  Announce the disk to the world. */
7064
7065	rc = device_add(&rbd_dev->dev);
7066	if (rc)
7067		goto err_out_image_lock;
7068
7069	device_add_disk(&rbd_dev->dev, rbd_dev->disk, NULL);
7070
7071	spin_lock(&rbd_dev_list_lock);
7072	list_add_tail(&rbd_dev->node, &rbd_dev_list);
7073	spin_unlock(&rbd_dev_list_lock);
7074
7075	pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name,
7076		(unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT,
7077		rbd_dev->header.features);
7078	rc = count;
7079out:
7080	module_put(THIS_MODULE);
7081	return rc;
7082
7083err_out_image_lock:
7084	rbd_dev_image_unlock(rbd_dev);
7085	rbd_dev_device_release(rbd_dev);
7086err_out_image_probe:
7087	rbd_dev_image_release(rbd_dev);
7088err_out_rbd_dev:
7089	rbd_dev_destroy(rbd_dev);
7090err_out_client:
7091	rbd_put_client(rbdc);
7092err_out_args:
7093	rbd_spec_put(spec);
7094	kfree(rbd_opts);
7095	goto out;
7096}
7097
7098static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count)
7099{
7100	if (single_major)
7101		return -EINVAL;
7102
7103	return do_rbd_add(bus, buf, count);
7104}
7105
7106static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
7107				      size_t count)
7108{
7109	return do_rbd_add(bus, buf, count);
7110}
7111
7112static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
7113{
7114	while (rbd_dev->parent) {
7115		struct rbd_device *first = rbd_dev;
7116		struct rbd_device *second = first->parent;
7117		struct rbd_device *third;
7118
7119		/*
7120		 * Follow to the parent with no grandparent and
7121		 * remove it.
7122		 */
7123		while (second && (third = second->parent)) {
7124			first = second;
7125			second = third;
7126		}
7127		rbd_assert(second);
7128		rbd_dev_image_release(second);
7129		rbd_dev_destroy(second);
7130		first->parent = NULL;
7131		first->parent_overlap = 0;
7132
7133		rbd_assert(first->parent_spec);
7134		rbd_spec_put(first->parent_spec);
7135		first->parent_spec = NULL;
7136	}
7137}
7138
7139static ssize_t do_rbd_remove(struct bus_type *bus,
7140			     const char *buf,
7141			     size_t count)
7142{
7143	struct rbd_device *rbd_dev = NULL;
7144	struct list_head *tmp;
7145	int dev_id;
7146	char opt_buf[6];
7147	bool force = false;
7148	int ret;
7149
7150	if (!capable(CAP_SYS_ADMIN))
7151		return -EPERM;
7152
7153	dev_id = -1;
7154	opt_buf[0] = '\0';
7155	sscanf(buf, "%d %5s", &dev_id, opt_buf);
7156	if (dev_id < 0) {
7157		pr_err("dev_id out of range\n");
7158		return -EINVAL;
7159	}
7160	if (opt_buf[0] != '\0') {
7161		if (!strcmp(opt_buf, "force")) {
7162			force = true;
7163		} else {
7164			pr_err("bad remove option at '%s'\n", opt_buf);
7165			return -EINVAL;
7166		}
7167	}
7168
7169	ret = -ENOENT;
7170	spin_lock(&rbd_dev_list_lock);
7171	list_for_each(tmp, &rbd_dev_list) {
7172		rbd_dev = list_entry(tmp, struct rbd_device, node);
7173		if (rbd_dev->dev_id == dev_id) {
7174			ret = 0;
7175			break;
7176		}
7177	}
7178	if (!ret) {
7179		spin_lock_irq(&rbd_dev->lock);
7180		if (rbd_dev->open_count && !force)
7181			ret = -EBUSY;
7182		else if (test_and_set_bit(RBD_DEV_FLAG_REMOVING,
7183					  &rbd_dev->flags))
7184			ret = -EINPROGRESS;
7185		spin_unlock_irq(&rbd_dev->lock);
7186	}
7187	spin_unlock(&rbd_dev_list_lock);
7188	if (ret)
7189		return ret;
7190
7191	if (force) {
7192		/*
7193		 * Prevent new IO from being queued and wait for existing
7194		 * IO to complete/fail.
7195		 */
7196		blk_mq_freeze_queue(rbd_dev->disk->queue);
7197		blk_set_queue_dying(rbd_dev->disk->queue);
7198	}
7199
7200	del_gendisk(rbd_dev->disk);
7201	spin_lock(&rbd_dev_list_lock);
7202	list_del_init(&rbd_dev->node);
7203	spin_unlock(&rbd_dev_list_lock);
7204	device_del(&rbd_dev->dev);
7205
7206	rbd_dev_image_unlock(rbd_dev);
7207	rbd_dev_device_release(rbd_dev);
7208	rbd_dev_image_release(rbd_dev);
7209	rbd_dev_destroy(rbd_dev);
7210	return count;
7211}
7212
7213static ssize_t remove_store(struct bus_type *bus, const char *buf, size_t count)
7214{
7215	if (single_major)
7216		return -EINVAL;
7217
7218	return do_rbd_remove(bus, buf, count);
7219}
7220
7221static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
7222					 size_t count)
7223{
7224	return do_rbd_remove(bus, buf, count);
7225}
7226
7227/*
7228 * create control files in sysfs
7229 * /sys/bus/rbd/...
7230 */
7231static int __init rbd_sysfs_init(void)
7232{
7233	int ret;
7234
7235	ret = device_register(&rbd_root_dev);
7236	if (ret < 0)
 
 
7237		return ret;
7238
7239	ret = bus_register(&rbd_bus_type);
7240	if (ret < 0)
7241		device_unregister(&rbd_root_dev);
7242
7243	return ret;
7244}
7245
7246static void __exit rbd_sysfs_cleanup(void)
7247{
 
7248	bus_unregister(&rbd_bus_type);
7249	device_unregister(&rbd_root_dev);
7250}
7251
7252static int __init rbd_slab_init(void)
7253{
7254	rbd_assert(!rbd_img_request_cache);
7255	rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0);
7256	if (!rbd_img_request_cache)
7257		return -ENOMEM;
7258
7259	rbd_assert(!rbd_obj_request_cache);
7260	rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0);
7261	if (!rbd_obj_request_cache)
7262		goto out_err;
7263
7264	return 0;
7265
7266out_err:
7267	kmem_cache_destroy(rbd_img_request_cache);
7268	rbd_img_request_cache = NULL;
7269	return -ENOMEM;
7270}
7271
7272static void rbd_slab_exit(void)
7273{
7274	rbd_assert(rbd_obj_request_cache);
7275	kmem_cache_destroy(rbd_obj_request_cache);
7276	rbd_obj_request_cache = NULL;
7277
7278	rbd_assert(rbd_img_request_cache);
7279	kmem_cache_destroy(rbd_img_request_cache);
7280	rbd_img_request_cache = NULL;
7281}
7282
7283static int __init rbd_init(void)
7284{
7285	int rc;
7286
7287	if (!libceph_compatible(NULL)) {
7288		rbd_warn(NULL, "libceph incompatibility (quitting)");
7289		return -EINVAL;
7290	}
7291
7292	rc = rbd_slab_init();
7293	if (rc)
7294		return rc;
7295
7296	/*
7297	 * The number of active work items is limited by the number of
7298	 * rbd devices * queue depth, so leave @max_active at default.
7299	 */
7300	rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
7301	if (!rbd_wq) {
7302		rc = -ENOMEM;
7303		goto err_out_slab;
7304	}
7305
7306	if (single_major) {
7307		rbd_major = register_blkdev(0, RBD_DRV_NAME);
7308		if (rbd_major < 0) {
7309			rc = rbd_major;
7310			goto err_out_wq;
7311		}
7312	}
7313
7314	rc = rbd_sysfs_init();
7315	if (rc)
7316		goto err_out_blkdev;
7317
7318	if (single_major)
7319		pr_info("loaded (major %d)\n", rbd_major);
7320	else
7321		pr_info("loaded\n");
7322
7323	return 0;
7324
7325err_out_blkdev:
7326	if (single_major)
7327		unregister_blkdev(rbd_major, RBD_DRV_NAME);
7328err_out_wq:
7329	destroy_workqueue(rbd_wq);
7330err_out_slab:
7331	rbd_slab_exit();
7332	return rc;
7333}
7334
7335static void __exit rbd_exit(void)
7336{
7337	ida_destroy(&rbd_dev_id_ida);
7338	rbd_sysfs_cleanup();
7339	if (single_major)
7340		unregister_blkdev(rbd_major, RBD_DRV_NAME);
7341	destroy_workqueue(rbd_wq);
7342	rbd_slab_exit();
7343}
7344
7345module_init(rbd_init);
7346module_exit(rbd_exit);
7347
7348MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
7349MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
7350MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
 
 
7351/* following authorship retained from original osdblk.c */
7352MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
7353
7354MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
7355MODULE_LICENSE("GPL");