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   1/*
   2 * Copyright (C) 2005, 2006
   3 * Avishay Traeger (avishay@gmail.com)
   4 * Copyright (C) 2008, 2009
   5 * Boaz Harrosh <bharrosh@panasas.com>
   6 *
   7 * Copyrights for code taken from ext2:
   8 *     Copyright (C) 1992, 1993, 1994, 1995
   9 *     Remy Card (card@masi.ibp.fr)
  10 *     Laboratoire MASI - Institut Blaise Pascal
  11 *     Universite Pierre et Marie Curie (Paris VI)
  12 *     from
  13 *     linux/fs/minix/inode.c
  14 *     Copyright (C) 1991, 1992  Linus Torvalds
  15 *
  16 * This file is part of exofs.
  17 *
  18 * exofs is free software; you can redistribute it and/or modify
  19 * it under the terms of the GNU General Public License as published by
  20 * the Free Software Foundation.  Since it is based on ext2, and the only
  21 * valid version of GPL for the Linux kernel is version 2, the only valid
  22 * version of GPL for exofs is version 2.
  23 *
  24 * exofs is distributed in the hope that it will be useful,
  25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27 * GNU General Public License for more details.
  28 *
  29 * You should have received a copy of the GNU General Public License
  30 * along with exofs; if not, write to the Free Software
  31 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  32 */
  33
  34#include <linux/string.h>
  35#include <linux/parser.h>
  36#include <linux/vfs.h>
  37#include <linux/random.h>
  38#include <linux/exportfs.h>
  39#include <linux/slab.h>
  40
  41#include "exofs.h"
  42
  43#define EXOFS_DBGMSG2(M...) do {} while (0)
  44
  45/******************************************************************************
  46 * MOUNT OPTIONS
  47 *****************************************************************************/
  48
  49/*
  50 * struct to hold what we get from mount options
  51 */
  52struct exofs_mountopt {
  53	bool is_osdname;
  54	const char *dev_name;
  55	uint64_t pid;
  56	int timeout;
  57};
  58
  59/*
  60 * exofs-specific mount-time options.
  61 */
  62enum { Opt_name, Opt_pid, Opt_to, Opt_err };
  63
  64/*
  65 * Our mount-time options.  These should ideally be 64-bit unsigned, but the
  66 * kernel's parsing functions do not currently support that.  32-bit should be
  67 * sufficient for most applications now.
  68 */
  69static match_table_t tokens = {
  70	{Opt_name, "osdname=%s"},
  71	{Opt_pid, "pid=%u"},
  72	{Opt_to, "to=%u"},
  73	{Opt_err, NULL}
  74};
  75
  76/*
  77 * The main option parsing method.  Also makes sure that all of the mandatory
  78 * mount options were set.
  79 */
  80static int parse_options(char *options, struct exofs_mountopt *opts)
  81{
  82	char *p;
  83	substring_t args[MAX_OPT_ARGS];
  84	int option;
  85	bool s_pid = false;
  86
  87	EXOFS_DBGMSG("parse_options %s\n", options);
  88	/* defaults */
  89	memset(opts, 0, sizeof(*opts));
  90	opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
  91
  92	while ((p = strsep(&options, ",")) != NULL) {
  93		int token;
  94		char str[32];
  95
  96		if (!*p)
  97			continue;
  98
  99		token = match_token(p, tokens, args);
 100		switch (token) {
 101		case Opt_name:
 102			opts->dev_name = match_strdup(&args[0]);
 103			if (unlikely(!opts->dev_name)) {
 104				EXOFS_ERR("Error allocating dev_name");
 105				return -ENOMEM;
 106			}
 107			opts->is_osdname = true;
 108			break;
 109		case Opt_pid:
 110			if (0 == match_strlcpy(str, &args[0], sizeof(str)))
 111				return -EINVAL;
 112			opts->pid = simple_strtoull(str, NULL, 0);
 113			if (opts->pid < EXOFS_MIN_PID) {
 114				EXOFS_ERR("Partition ID must be >= %u",
 115					  EXOFS_MIN_PID);
 116				return -EINVAL;
 117			}
 118			s_pid = 1;
 119			break;
 120		case Opt_to:
 121			if (match_int(&args[0], &option))
 122				return -EINVAL;
 123			if (option <= 0) {
 124				EXOFS_ERR("Timout must be > 0");
 125				return -EINVAL;
 126			}
 127			opts->timeout = option * HZ;
 128			break;
 129		}
 130	}
 131
 132	if (!s_pid) {
 133		EXOFS_ERR("Need to specify the following options:\n");
 134		EXOFS_ERR("    -o pid=pid_no_to_use\n");
 135		return -EINVAL;
 136	}
 137
 138	return 0;
 139}
 140
 141/******************************************************************************
 142 * INODE CACHE
 143 *****************************************************************************/
 144
 145/*
 146 * Our inode cache.  Isn't it pretty?
 147 */
 148static struct kmem_cache *exofs_inode_cachep;
 149
 150/*
 151 * Allocate an inode in the cache
 152 */
 153static struct inode *exofs_alloc_inode(struct super_block *sb)
 154{
 155	struct exofs_i_info *oi;
 156
 157	oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
 158	if (!oi)
 159		return NULL;
 160
 161	oi->vfs_inode.i_version = 1;
 162	return &oi->vfs_inode;
 163}
 164
 165static void exofs_i_callback(struct rcu_head *head)
 166{
 167	struct inode *inode = container_of(head, struct inode, i_rcu);
 168	INIT_LIST_HEAD(&inode->i_dentry);
 169	kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
 170}
 171
 172/*
 173 * Remove an inode from the cache
 174 */
 175static void exofs_destroy_inode(struct inode *inode)
 176{
 177	call_rcu(&inode->i_rcu, exofs_i_callback);
 178}
 179
 180/*
 181 * Initialize the inode
 182 */
 183static void exofs_init_once(void *foo)
 184{
 185	struct exofs_i_info *oi = foo;
 186
 187	inode_init_once(&oi->vfs_inode);
 188}
 189
 190/*
 191 * Create and initialize the inode cache
 192 */
 193static int init_inodecache(void)
 194{
 195	exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
 196				sizeof(struct exofs_i_info), 0,
 197				SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
 198				exofs_init_once);
 199	if (exofs_inode_cachep == NULL)
 200		return -ENOMEM;
 201	return 0;
 202}
 203
 204/*
 205 * Destroy the inode cache
 206 */
 207static void destroy_inodecache(void)
 208{
 209	kmem_cache_destroy(exofs_inode_cachep);
 210}
 211
 212/******************************************************************************
 213 * Some osd helpers
 214 *****************************************************************************/
 215void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
 216{
 217	osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
 218}
 219
 220static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
 221		    u64 offset, void *p, unsigned length)
 222{
 223	struct osd_request *or = osd_start_request(od, GFP_KERNEL);
 224/*	struct osd_sense_info osi = {.key = 0};*/
 225	int ret;
 226
 227	if (unlikely(!or)) {
 228		EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
 229		return -ENOMEM;
 230	}
 231	ret = osd_req_read_kern(or, obj, offset, p, length);
 232	if (unlikely(ret)) {
 233		EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
 234		goto out;
 235	}
 236
 237	ret = osd_finalize_request(or, 0, cred, NULL);
 238	if (unlikely(ret)) {
 239		EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
 240		goto out;
 241	}
 242
 243	ret = osd_execute_request(or);
 244	if (unlikely(ret))
 245		EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
 246	/* osd_req_decode_sense(or, ret); */
 247
 248out:
 249	osd_end_request(or);
 250	EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 251		      "length=0x%llx dev=%p ret=>%d\n",
 252		      _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
 253	return ret;
 254}
 255
 256static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
 257	EXOFS_APAGE_SB_DATA,
 258	EXOFS_ATTR_SB_STATS,
 259	sizeof(struct exofs_sb_stats));
 260
 261static int __sbi_read_stats(struct exofs_sb_info *sbi)
 262{
 263	struct osd_attr attrs[] = {
 264		[0] = g_attr_sb_stats,
 265	};
 266	struct ore_io_state *ios;
 267	int ret;
 268
 269	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 270	if (unlikely(ret)) {
 271		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 272		return ret;
 273	}
 274
 275	ios->in_attr = attrs;
 276	ios->in_attr_len = ARRAY_SIZE(attrs);
 277
 278	ret = ore_read(ios);
 279	if (unlikely(ret)) {
 280		EXOFS_ERR("Error reading super_block stats => %d\n", ret);
 281		goto out;
 282	}
 283
 284	ret = extract_attr_from_ios(ios, &attrs[0]);
 285	if (ret) {
 286		EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
 287		goto out;
 288	}
 289	if (attrs[0].len) {
 290		struct exofs_sb_stats *ess;
 291
 292		if (unlikely(attrs[0].len != sizeof(*ess))) {
 293			EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
 294				  "size(%d) != expected(%zd)\n",
 295				  __func__, attrs[0].len, sizeof(*ess));
 296			goto out;
 297		}
 298
 299		ess = attrs[0].val_ptr;
 300		sbi->s_nextid = le64_to_cpu(ess->s_nextid);
 301		sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
 302	}
 303
 304out:
 305	ore_put_io_state(ios);
 306	return ret;
 307}
 308
 309static void stats_done(struct ore_io_state *ios, void *p)
 310{
 311	ore_put_io_state(ios);
 312	/* Good thanks nothing to do anymore */
 313}
 314
 315/* Asynchronously write the stats attribute */
 316int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
 317{
 318	struct osd_attr attrs[] = {
 319		[0] = g_attr_sb_stats,
 320	};
 321	struct ore_io_state *ios;
 322	int ret;
 323
 324	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 325	if (unlikely(ret)) {
 326		EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 327		return ret;
 328	}
 329
 330	sbi->s_ess.s_nextid   = cpu_to_le64(sbi->s_nextid);
 331	sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
 332	attrs[0].val_ptr = &sbi->s_ess;
 333
 334
 335	ios->done = stats_done;
 336	ios->private = sbi;
 337	ios->out_attr = attrs;
 338	ios->out_attr_len = ARRAY_SIZE(attrs);
 339
 340	ret = ore_write(ios);
 341	if (unlikely(ret)) {
 342		EXOFS_ERR("%s: ore_write failed.\n", __func__);
 343		ore_put_io_state(ios);
 344	}
 345
 346	return ret;
 347}
 348
 349/******************************************************************************
 350 * SUPERBLOCK FUNCTIONS
 351 *****************************************************************************/
 352static const struct super_operations exofs_sops;
 353static const struct export_operations exofs_export_ops;
 354
 355/*
 356 * Write the superblock to the OSD
 357 */
 358int exofs_sync_fs(struct super_block *sb, int wait)
 359{
 360	struct exofs_sb_info *sbi;
 361	struct exofs_fscb *fscb;
 362	struct ore_comp one_comp;
 363	struct ore_components comps;
 364	struct ore_io_state *ios;
 365	int ret = -ENOMEM;
 366
 367	fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
 368	if (unlikely(!fscb))
 369		return -ENOMEM;
 370
 371	sbi = sb->s_fs_info;
 372
 373	/* NOTE: We no longer dirty the super_block anywhere in exofs. The
 374	 * reason we write the fscb here on unmount is so we can stay backwards
 375	 * compatible with fscb->s_version == 1. (What we are not compatible
 376	 * with is if a new version FS crashed and then we try to mount an old
 377	 * version). Otherwise the exofs_fscb is read-only from mkfs time. All
 378	 * the writeable info is set in exofs_sbi_write_stats() above.
 379	 */
 380
 381	exofs_init_comps(&comps, &one_comp, sbi, EXOFS_SUPER_ID);
 382
 383	ret = ore_get_io_state(&sbi->layout, &comps, &ios);
 384	if (unlikely(ret))
 385		goto out;
 386
 387	lock_super(sb);
 388
 389	ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
 390	memset(fscb, 0, ios->length);
 391	fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
 392	fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
 393	fscb->s_magic = cpu_to_le16(sb->s_magic);
 394	fscb->s_newfs = 0;
 395	fscb->s_version = EXOFS_FSCB_VER;
 396
 397	ios->offset = 0;
 398	ios->kern_buff = fscb;
 399
 400	ret = ore_write(ios);
 401	if (unlikely(ret))
 402		EXOFS_ERR("%s: ore_write failed.\n", __func__);
 403	else
 404		sb->s_dirt = 0;
 405
 406
 407	unlock_super(sb);
 408out:
 409	EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
 410	ore_put_io_state(ios);
 411	kfree(fscb);
 412	return ret;
 413}
 414
 415static void exofs_write_super(struct super_block *sb)
 416{
 417	if (!(sb->s_flags & MS_RDONLY))
 418		exofs_sync_fs(sb, 1);
 419	else
 420		sb->s_dirt = 0;
 421}
 422
 423static void _exofs_print_device(const char *msg, const char *dev_path,
 424				struct osd_dev *od, u64 pid)
 425{
 426	const struct osd_dev_info *odi = osduld_device_info(od);
 427
 428	printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
 429		msg, dev_path ?: "", odi->osdname, _LLU(pid));
 430}
 431
 432void exofs_free_sbi(struct exofs_sb_info *sbi)
 433{
 434	while (sbi->comps.numdevs) {
 435		int i = --sbi->comps.numdevs;
 436		struct osd_dev *od = sbi->comps.ods[i];
 437
 438		if (od) {
 439			sbi->comps.ods[i] = NULL;
 440			osduld_put_device(od);
 441		}
 442	}
 443	if (sbi->comps.ods != sbi->_min_one_dev)
 444		kfree(sbi->comps.ods);
 445	kfree(sbi);
 446}
 447
 448/*
 449 * This function is called when the vfs is freeing the superblock.  We just
 450 * need to free our own part.
 451 */
 452static void exofs_put_super(struct super_block *sb)
 453{
 454	int num_pend;
 455	struct exofs_sb_info *sbi = sb->s_fs_info;
 456
 457	/* make sure there are no pending commands */
 458	for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
 459	     num_pend = atomic_read(&sbi->s_curr_pending)) {
 460		wait_queue_head_t wq;
 461
 462		printk(KERN_NOTICE "%s: !!Pending operations in flight. "
 463		       "This is a BUG. please report to osd-dev@open-osd.org\n",
 464		       __func__);
 465		init_waitqueue_head(&wq);
 466		wait_event_timeout(wq,
 467				  (atomic_read(&sbi->s_curr_pending) == 0),
 468				  msecs_to_jiffies(100));
 469	}
 470
 471	_exofs_print_device("Unmounting", NULL, sbi->comps.ods[0],
 472			    sbi->one_comp.obj.partition);
 473
 474	bdi_destroy(&sbi->bdi);
 475	exofs_free_sbi(sbi);
 476	sb->s_fs_info = NULL;
 477}
 478
 479static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 480				    struct exofs_device_table *dt)
 481{
 482	u64 stripe_length;
 483
 484	sbi->data_map.odm_num_comps   =
 485				le32_to_cpu(dt->dt_data_map.cb_num_comps);
 486	sbi->data_map.odm_stripe_unit =
 487				le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
 488	sbi->data_map.odm_group_width =
 489				le32_to_cpu(dt->dt_data_map.cb_group_width);
 490	sbi->data_map.odm_group_depth =
 491				le32_to_cpu(dt->dt_data_map.cb_group_depth);
 492	sbi->data_map.odm_mirror_cnt  =
 493				le32_to_cpu(dt->dt_data_map.cb_mirror_cnt);
 494	sbi->data_map.odm_raid_algorithm  =
 495				le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 496
 497/* FIXME: Only raid0 for now. if not so, do not mount */
 498	if (sbi->data_map.odm_num_comps != numdevs) {
 499		EXOFS_ERR("odm_num_comps(%u) != numdevs(%u)\n",
 500			  sbi->data_map.odm_num_comps, numdevs);
 501		return -EINVAL;
 502	}
 503	if (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) {
 504		EXOFS_ERR("Only RAID_0 for now\n");
 505		return -EINVAL;
 506	}
 507	if (0 != (numdevs % (sbi->data_map.odm_mirror_cnt + 1))) {
 508		EXOFS_ERR("Data Map wrong, numdevs=%d mirrors=%d\n",
 509			  numdevs, sbi->data_map.odm_mirror_cnt);
 510		return -EINVAL;
 511	}
 512
 513	if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
 514		EXOFS_ERR("Stripe Unit(0x%llx)"
 515			  " must be Multples of PAGE_SIZE(0x%lx)\n",
 516			  _LLU(sbi->data_map.odm_stripe_unit), PAGE_SIZE);
 517		return -EINVAL;
 518	}
 519
 520	sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
 521	sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
 522
 523	if (sbi->data_map.odm_group_width) {
 524		sbi->layout.group_width = sbi->data_map.odm_group_width;
 525		sbi->layout.group_depth = sbi->data_map.odm_group_depth;
 526		if (!sbi->layout.group_depth) {
 527			EXOFS_ERR("group_depth == 0 && group_width != 0\n");
 528			return -EINVAL;
 529		}
 530		sbi->layout.group_count = sbi->data_map.odm_num_comps /
 531						sbi->layout.mirrors_p1 /
 532						sbi->data_map.odm_group_width;
 533	} else {
 534		if (sbi->data_map.odm_group_depth) {
 535			printk(KERN_NOTICE "Warning: group_depth ignored "
 536				"group_width == 0 && group_depth == %d\n",
 537				sbi->data_map.odm_group_depth);
 538			sbi->data_map.odm_group_depth = 0;
 539		}
 540		sbi->layout.group_width = sbi->data_map.odm_num_comps /
 541							sbi->layout.mirrors_p1;
 542		sbi->layout.group_depth = -1;
 543		sbi->layout.group_count = 1;
 544	}
 545
 546	stripe_length = (u64)sbi->layout.group_width * sbi->layout.stripe_unit;
 547	if (stripe_length >= (1ULL << 32)) {
 548		EXOFS_ERR("Total Stripe length(0x%llx)"
 549			  " >= 32bit is not supported\n", _LLU(stripe_length));
 550		return -EINVAL;
 551	}
 552
 553	EXOFS_DBGMSG("exofs: layout: "
 554		"num_comps=%u stripe_unit=0x%x group_width=%u "
 555		"group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
 556		numdevs,
 557		sbi->layout.stripe_unit,
 558		sbi->layout.group_width,
 559		_LLU(sbi->layout.group_depth),
 560		sbi->layout.mirrors_p1,
 561		sbi->data_map.odm_raid_algorithm);
 562	return 0;
 563}
 564
 565static unsigned __ra_pages(struct ore_layout *layout)
 566{
 567	const unsigned _MIN_RA = 32; /* min 128K read-ahead */
 568	unsigned ra_pages = layout->group_width * layout->stripe_unit /
 569				PAGE_SIZE;
 570	unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
 571
 572	ra_pages *= 2; /* two stripes */
 573	if (ra_pages < _MIN_RA)
 574		ra_pages = roundup(_MIN_RA, ra_pages / 2);
 575
 576	if (ra_pages > max_io_pages)
 577		ra_pages = max_io_pages;
 578
 579	return ra_pages;
 580}
 581
 582/* @odi is valid only as long as @fscb_dev is valid */
 583static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 584			     struct osd_dev_info *odi)
 585{
 586	odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
 587	memcpy(odi->systemid, dt_dev->systemid, odi->systemid_len);
 588
 589	odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
 590	odi->osdname = dt_dev->osdname;
 591
 592	/* FIXME support long names. Will need a _put function */
 593	if (dt_dev->long_name_offset)
 594		return -EINVAL;
 595
 596	/* Make sure osdname is printable!
 597	 * mkexofs should give us space for a null-terminator else the
 598	 * device-table is invalid.
 599	 */
 600	if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
 601		odi->osdname_len = sizeof(dt_dev->osdname) - 1;
 602	dt_dev->osdname[odi->osdname_len] = 0;
 603
 604	/* If it's all zeros something is bad we read past end-of-obj */
 605	return !(odi->systemid_len || odi->osdname_len);
 606}
 607
 608static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
 609				       struct osd_dev *fscb_od,
 610				       unsigned table_count)
 611{
 612	struct ore_comp comp;
 613	struct exofs_device_table *dt;
 614	unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 615					     sizeof(*dt);
 616	unsigned numdevs, i;
 617	int ret;
 618
 619	dt = kmalloc(table_bytes, GFP_KERNEL);
 620	if (unlikely(!dt)) {
 621		EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
 622			  table_bytes);
 623		return -ENOMEM;
 624	}
 625
 626	sbi->comps.numdevs = 0;
 627
 628	comp.obj.partition = sbi->one_comp.obj.partition;
 629	comp.obj.id = EXOFS_DEVTABLE_ID;
 630	exofs_make_credential(comp.cred, &comp.obj);
 631
 632	ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
 633			      table_bytes);
 634	if (unlikely(ret)) {
 635		EXOFS_ERR("ERROR: reading device table\n");
 636		goto out;
 637	}
 638
 639	numdevs = le64_to_cpu(dt->dt_num_devices);
 640	if (unlikely(!numdevs)) {
 641		ret = -EINVAL;
 642		goto out;
 643	}
 644	WARN_ON(table_count != numdevs);
 645
 646	ret = _read_and_match_data_map(sbi, numdevs, dt);
 647	if (unlikely(ret))
 648		goto out;
 649
 650	if (likely(numdevs > 1)) {
 651		unsigned size = numdevs * sizeof(sbi->comps.ods[0]);
 652
 653		/* Twice bigger table: See exofs_init_comps() and below
 654		 * comment
 655		 */
 656		sbi->comps.ods = kzalloc(size + size - 1, GFP_KERNEL);
 657		if (unlikely(!sbi->comps.ods)) {
 658			EXOFS_ERR("ERROR: faild allocating Device array[%d]\n",
 659				  numdevs);
 660			ret = -ENOMEM;
 661			goto out;
 662		}
 663	}
 664
 665	for (i = 0; i < numdevs; i++) {
 666		struct exofs_fscb fscb;
 667		struct osd_dev_info odi;
 668		struct osd_dev *od;
 669
 670		if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
 671			EXOFS_ERR("ERROR: Read all-zeros device entry\n");
 672			ret = -EINVAL;
 673			goto out;
 674		}
 675
 676		printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
 677		       i, odi.osdname);
 678
 679		/* On all devices the device table is identical. The user can
 680		 * specify any one of the participating devices on the command
 681		 * line. We always keep them in device-table order.
 682		 */
 683		if (fscb_od && osduld_device_same(fscb_od, &odi)) {
 684			sbi->comps.ods[i] = fscb_od;
 685			++sbi->comps.numdevs;
 686			fscb_od = NULL;
 687			continue;
 688		}
 689
 690		od = osduld_info_lookup(&odi);
 691		if (IS_ERR(od)) {
 692			ret = PTR_ERR(od);
 693			EXOFS_ERR("ERROR: device requested is not found "
 694				  "osd_name-%s =>%d\n", odi.osdname, ret);
 695			goto out;
 696		}
 697
 698		sbi->comps.ods[i] = od;
 699		++sbi->comps.numdevs;
 700
 701		/* Read the fscb of the other devices to make sure the FS
 702		 * partition is there.
 703		 */
 704		ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
 705				      sizeof(fscb));
 706		if (unlikely(ret)) {
 707			EXOFS_ERR("ERROR: Malformed participating device "
 708				  "error reading fscb osd_name-%s\n",
 709				  odi.osdname);
 710			goto out;
 711		}
 712
 713		/* TODO: verify other information is correct and FS-uuid
 714		 *	 matches. Benny what did you say about device table
 715		 *	 generation and old devices?
 716		 */
 717	}
 718
 719out:
 720	kfree(dt);
 721	if (likely(!ret)) {
 722		unsigned numdevs = sbi->comps.numdevs;
 723
 724		if (unlikely(fscb_od)) {
 725			EXOFS_ERR("ERROR: Bad device-table container device not present\n");
 726			osduld_put_device(fscb_od);
 727			return -EINVAL;
 728		}
 729		/* exofs round-robins the device table view according to inode
 730		 * number. We hold a: twice bigger table hence inodes can point
 731		 * to any device and have a sequential view of the table
 732		 * starting at this device. See exofs_init_comps()
 733		 */
 734		for (i = 0; i < numdevs - 1; ++i)
 735			sbi->comps.ods[i + numdevs] = sbi->comps.ods[i];
 736	}
 737	return ret;
 738}
 739
 740/*
 741 * Read the superblock from the OSD and fill in the fields
 742 */
 743static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 744{
 745	struct inode *root;
 746	struct exofs_mountopt *opts = data;
 747	struct exofs_sb_info *sbi;	/*extended info                  */
 748	struct osd_dev *od;		/* Master device                 */
 749	struct exofs_fscb fscb;		/*on-disk superblock info        */
 750	struct ore_comp comp;
 751	unsigned table_count;
 752	int ret;
 753
 754	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 755	if (!sbi)
 756		return -ENOMEM;
 757
 758	/* use mount options to fill superblock */
 759	if (opts->is_osdname) {
 760		struct osd_dev_info odi = {.systemid_len = 0};
 761
 762		odi.osdname_len = strlen(opts->dev_name);
 763		odi.osdname = (u8 *)opts->dev_name;
 764		od = osduld_info_lookup(&odi);
 765		kfree(opts->dev_name);
 766		opts->dev_name = NULL;
 767	} else {
 768		od = osduld_path_lookup(opts->dev_name);
 769	}
 770	if (IS_ERR(od)) {
 771		ret = -EINVAL;
 772		goto free_sbi;
 773	}
 774
 775	/* Default layout in case we do not have a device-table */
 776	sbi->layout.stripe_unit = PAGE_SIZE;
 777	sbi->layout.mirrors_p1 = 1;
 778	sbi->layout.group_width = 1;
 779	sbi->layout.group_depth = -1;
 780	sbi->layout.group_count = 1;
 781	sbi->s_timeout = opts->timeout;
 782
 783	sbi->one_comp.obj.partition = opts->pid;
 784	sbi->one_comp.obj.id = 0;
 785	exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
 786	sbi->comps.numdevs = 1;
 787	sbi->comps.single_comp = EC_SINGLE_COMP;
 788	sbi->comps.comps = &sbi->one_comp;
 789	sbi->comps.ods = sbi->_min_one_dev;
 790
 791	/* fill in some other data by hand */
 792	memset(sb->s_id, 0, sizeof(sb->s_id));
 793	strcpy(sb->s_id, "exofs");
 794	sb->s_blocksize = EXOFS_BLKSIZE;
 795	sb->s_blocksize_bits = EXOFS_BLKSHIFT;
 796	sb->s_maxbytes = MAX_LFS_FILESIZE;
 797	atomic_set(&sbi->s_curr_pending, 0);
 798	sb->s_bdev = NULL;
 799	sb->s_dev = 0;
 800
 801	comp.obj.partition = sbi->one_comp.obj.partition;
 802	comp.obj.id = EXOFS_SUPER_ID;
 803	exofs_make_credential(comp.cred, &comp.obj);
 804
 805	ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
 806	if (unlikely(ret))
 807		goto free_sbi;
 808
 809	sb->s_magic = le16_to_cpu(fscb.s_magic);
 810	/* NOTE: we read below to be backward compatible with old versions */
 811	sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
 812	sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
 813
 814	/* make sure what we read from the object store is correct */
 815	if (sb->s_magic != EXOFS_SUPER_MAGIC) {
 816		if (!silent)
 817			EXOFS_ERR("ERROR: Bad magic value\n");
 818		ret = -EINVAL;
 819		goto free_sbi;
 820	}
 821	if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
 822		EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
 823			  EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
 824		ret = -EINVAL;
 825		goto free_sbi;
 826	}
 827
 828	/* start generation numbers from a random point */
 829	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 830	spin_lock_init(&sbi->s_next_gen_lock);
 831
 832	table_count = le64_to_cpu(fscb.s_dev_table_count);
 833	if (table_count) {
 834		ret = exofs_read_lookup_dev_table(sbi, od, table_count);
 835		if (unlikely(ret))
 836			goto free_sbi;
 837	} else {
 838		sbi->comps.ods[0] = od;
 839	}
 840
 841	__sbi_read_stats(sbi);
 842
 843	/* set up operation vectors */
 844	sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
 845	sb->s_bdi = &sbi->bdi;
 846	sb->s_fs_info = sbi;
 847	sb->s_op = &exofs_sops;
 848	sb->s_export_op = &exofs_export_ops;
 849	root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
 850	if (IS_ERR(root)) {
 851		EXOFS_ERR("ERROR: exofs_iget failed\n");
 852		ret = PTR_ERR(root);
 853		goto free_sbi;
 854	}
 855	sb->s_root = d_alloc_root(root);
 856	if (!sb->s_root) {
 857		iput(root);
 858		EXOFS_ERR("ERROR: get root inode failed\n");
 859		ret = -ENOMEM;
 860		goto free_sbi;
 861	}
 862
 863	if (!S_ISDIR(root->i_mode)) {
 864		dput(sb->s_root);
 865		sb->s_root = NULL;
 866		EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
 867		       root->i_mode);
 868		ret = -EINVAL;
 869		goto free_sbi;
 870	}
 871
 872	ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
 873	if (ret) {
 874		EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
 875		goto free_sbi;
 876	}
 877
 878	_exofs_print_device("Mounting", opts->dev_name, sbi->comps.ods[0],
 879			    sbi->one_comp.obj.partition);
 880	return 0;
 881
 882free_sbi:
 883	EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
 884		  opts->dev_name, sbi->one_comp.obj.partition, ret);
 885	exofs_free_sbi(sbi);
 886	return ret;
 887}
 888
 889/*
 890 * Set up the superblock (calls exofs_fill_super eventually)
 891 */
 892static struct dentry *exofs_mount(struct file_system_type *type,
 893			  int flags, const char *dev_name,
 894			  void *data)
 895{
 896	struct exofs_mountopt opts;
 897	int ret;
 898
 899	ret = parse_options(data, &opts);
 900	if (ret)
 901		return ERR_PTR(ret);
 902
 903	if (!opts.dev_name)
 904		opts.dev_name = dev_name;
 905	return mount_nodev(type, flags, &opts, exofs_fill_super);
 906}
 907
 908/*
 909 * Return information about the file system state in the buffer.  This is used
 910 * by the 'df' command, for example.
 911 */
 912static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 913{
 914	struct super_block *sb = dentry->d_sb;
 915	struct exofs_sb_info *sbi = sb->s_fs_info;
 916	struct ore_io_state *ios;
 917	struct osd_attr attrs[] = {
 918		ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 919			OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
 920		ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
 921			OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
 922	};
 923	uint64_t capacity = ULLONG_MAX;
 924	uint64_t used = ULLONG_MAX;
 925	int ret;
 926
 927	ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 928	if (ret) {
 929		EXOFS_DBGMSG("ore_get_io_state failed.\n");
 930		return ret;
 931	}
 932
 933	ios->in_attr = attrs;
 934	ios->in_attr_len = ARRAY_SIZE(attrs);
 935
 936	ret = ore_read(ios);
 937	if (unlikely(ret))
 938		goto out;
 939
 940	ret = extract_attr_from_ios(ios, &attrs[0]);
 941	if (likely(!ret)) {
 942		capacity = get_unaligned_be64(attrs[0].val_ptr);
 943		if (unlikely(!capacity))
 944			capacity = ULLONG_MAX;
 945	} else
 946		EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
 947
 948	ret = extract_attr_from_ios(ios, &attrs[1]);
 949	if (likely(!ret))
 950		used = get_unaligned_be64(attrs[1].val_ptr);
 951	else
 952		EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
 953
 954	/* fill in the stats buffer */
 955	buf->f_type = EXOFS_SUPER_MAGIC;
 956	buf->f_bsize = EXOFS_BLKSIZE;
 957	buf->f_blocks = capacity >> 9;
 958	buf->f_bfree = (capacity - used) >> 9;
 959	buf->f_bavail = buf->f_bfree;
 960	buf->f_files = sbi->s_numfiles;
 961	buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
 962	buf->f_namelen = EXOFS_NAME_LEN;
 963
 964out:
 965	ore_put_io_state(ios);
 966	return ret;
 967}
 968
 969static const struct super_operations exofs_sops = {
 970	.alloc_inode    = exofs_alloc_inode,
 971	.destroy_inode  = exofs_destroy_inode,
 972	.write_inode    = exofs_write_inode,
 973	.evict_inode    = exofs_evict_inode,
 974	.put_super      = exofs_put_super,
 975	.write_super    = exofs_write_super,
 976	.sync_fs	= exofs_sync_fs,
 977	.statfs         = exofs_statfs,
 978};
 979
 980/******************************************************************************
 981 * EXPORT OPERATIONS
 982 *****************************************************************************/
 983
 984struct dentry *exofs_get_parent(struct dentry *child)
 985{
 986	unsigned long ino = exofs_parent_ino(child);
 987
 988	if (!ino)
 989		return ERR_PTR(-ESTALE);
 990
 991	return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
 992}
 993
 994static struct inode *exofs_nfs_get_inode(struct super_block *sb,
 995		u64 ino, u32 generation)
 996{
 997	struct inode *inode;
 998
 999	inode = exofs_iget(sb, ino);
1000	if (IS_ERR(inode))
1001		return ERR_CAST(inode);
1002	if (generation && inode->i_generation != generation) {
1003		/* we didn't find the right inode.. */
1004		iput(inode);
1005		return ERR_PTR(-ESTALE);
1006	}
1007	return inode;
1008}
1009
1010static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
1011				struct fid *fid, int fh_len, int fh_type)
1012{
1013	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1014				    exofs_nfs_get_inode);
1015}
1016
1017static struct dentry *exofs_fh_to_parent(struct super_block *sb,
1018				struct fid *fid, int fh_len, int fh_type)
1019{
1020	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1021				    exofs_nfs_get_inode);
1022}
1023
1024static const struct export_operations exofs_export_ops = {
1025	.fh_to_dentry = exofs_fh_to_dentry,
1026	.fh_to_parent = exofs_fh_to_parent,
1027	.get_parent = exofs_get_parent,
1028};
1029
1030/******************************************************************************
1031 * INSMOD/RMMOD
1032 *****************************************************************************/
1033
1034/*
1035 * struct that describes this file system
1036 */
1037static struct file_system_type exofs_type = {
1038	.owner          = THIS_MODULE,
1039	.name           = "exofs",
1040	.mount          = exofs_mount,
1041	.kill_sb        = generic_shutdown_super,
1042};
1043
1044static int __init init_exofs(void)
1045{
1046	int err;
1047
1048	err = init_inodecache();
1049	if (err)
1050		goto out;
1051
1052	err = register_filesystem(&exofs_type);
1053	if (err)
1054		goto out_d;
1055
1056	return 0;
1057out_d:
1058	destroy_inodecache();
1059out:
1060	return err;
1061}
1062
1063static void __exit exit_exofs(void)
1064{
1065	unregister_filesystem(&exofs_type);
1066	destroy_inodecache();
1067}
1068
1069MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1070MODULE_DESCRIPTION("exofs");
1071MODULE_LICENSE("GPL");
1072
1073module_init(init_exofs)
1074module_exit(exit_exofs)