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v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/ceph/ceph_debug.h>
   3
   4#include <linux/fs.h>
   5#include <linux/kernel.h>
   6#include <linux/sched/signal.h>
   7#include <linux/slab.h>
   8#include <linux/vmalloc.h>
   9#include <linux/wait.h>
  10#include <linux/writeback.h>
  11
  12#include "super.h"
  13#include "mds_client.h"
  14#include "cache.h"
  15#include <linux/ceph/decode.h>
  16#include <linux/ceph/messenger.h>
  17
  18/*
  19 * Capability management
  20 *
  21 * The Ceph metadata servers control client access to inode metadata
  22 * and file data by issuing capabilities, granting clients permission
  23 * to read and/or write both inode field and file data to OSDs
  24 * (storage nodes).  Each capability consists of a set of bits
  25 * indicating which operations are allowed.
  26 *
  27 * If the client holds a *_SHARED cap, the client has a coherent value
  28 * that can be safely read from the cached inode.
  29 *
  30 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
  31 * client is allowed to change inode attributes (e.g., file size,
  32 * mtime), note its dirty state in the ceph_cap, and asynchronously
  33 * flush that metadata change to the MDS.
  34 *
  35 * In the event of a conflicting operation (perhaps by another
  36 * client), the MDS will revoke the conflicting client capabilities.
  37 *
  38 * In order for a client to cache an inode, it must hold a capability
  39 * with at least one MDS server.  When inodes are released, release
  40 * notifications are batched and periodically sent en masse to the MDS
  41 * cluster to release server state.
  42 */
  43
  44static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc);
  45static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
  46				 struct ceph_mds_session *session,
  47				 struct ceph_inode_info *ci,
  48				 u64 oldest_flush_tid);
  49
  50/*
  51 * Generate readable cap strings for debugging output.
  52 */
  53#define MAX_CAP_STR 20
  54static char cap_str[MAX_CAP_STR][40];
  55static DEFINE_SPINLOCK(cap_str_lock);
  56static int last_cap_str;
  57
  58static char *gcap_string(char *s, int c)
  59{
  60	if (c & CEPH_CAP_GSHARED)
  61		*s++ = 's';
  62	if (c & CEPH_CAP_GEXCL)
  63		*s++ = 'x';
  64	if (c & CEPH_CAP_GCACHE)
  65		*s++ = 'c';
  66	if (c & CEPH_CAP_GRD)
  67		*s++ = 'r';
  68	if (c & CEPH_CAP_GWR)
  69		*s++ = 'w';
  70	if (c & CEPH_CAP_GBUFFER)
  71		*s++ = 'b';
  72	if (c & CEPH_CAP_GLAZYIO)
  73		*s++ = 'l';
  74	return s;
  75}
  76
  77const char *ceph_cap_string(int caps)
  78{
  79	int i;
  80	char *s;
  81	int c;
  82
  83	spin_lock(&cap_str_lock);
  84	i = last_cap_str++;
  85	if (last_cap_str == MAX_CAP_STR)
  86		last_cap_str = 0;
  87	spin_unlock(&cap_str_lock);
  88
  89	s = cap_str[i];
  90
  91	if (caps & CEPH_CAP_PIN)
  92		*s++ = 'p';
  93
  94	c = (caps >> CEPH_CAP_SAUTH) & 3;
  95	if (c) {
  96		*s++ = 'A';
  97		s = gcap_string(s, c);
  98	}
  99
 100	c = (caps >> CEPH_CAP_SLINK) & 3;
 101	if (c) {
 102		*s++ = 'L';
 103		s = gcap_string(s, c);
 104	}
 105
 106	c = (caps >> CEPH_CAP_SXATTR) & 3;
 107	if (c) {
 108		*s++ = 'X';
 109		s = gcap_string(s, c);
 110	}
 111
 112	c = caps >> CEPH_CAP_SFILE;
 113	if (c) {
 114		*s++ = 'F';
 115		s = gcap_string(s, c);
 116	}
 117
 118	if (s == cap_str[i])
 119		*s++ = '-';
 120	*s = 0;
 121	return cap_str[i];
 122}
 123
 124void ceph_caps_init(struct ceph_mds_client *mdsc)
 125{
 126	INIT_LIST_HEAD(&mdsc->caps_list);
 127	spin_lock_init(&mdsc->caps_list_lock);
 128}
 129
 130void ceph_caps_finalize(struct ceph_mds_client *mdsc)
 131{
 132	struct ceph_cap *cap;
 133
 134	spin_lock(&mdsc->caps_list_lock);
 135	while (!list_empty(&mdsc->caps_list)) {
 136		cap = list_first_entry(&mdsc->caps_list,
 137				       struct ceph_cap, caps_item);
 138		list_del(&cap->caps_item);
 139		kmem_cache_free(ceph_cap_cachep, cap);
 140	}
 141	mdsc->caps_total_count = 0;
 142	mdsc->caps_avail_count = 0;
 143	mdsc->caps_use_count = 0;
 144	mdsc->caps_reserve_count = 0;
 145	mdsc->caps_min_count = 0;
 146	spin_unlock(&mdsc->caps_list_lock);
 147}
 148
 149void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
 150{
 151	spin_lock(&mdsc->caps_list_lock);
 152	mdsc->caps_min_count += delta;
 153	BUG_ON(mdsc->caps_min_count < 0);
 154	spin_unlock(&mdsc->caps_list_lock);
 155}
 156
 157/*
 158 * Called under mdsc->mutex.
 159 */
 160int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 161		      struct ceph_cap_reservation *ctx, int need)
 162{
 163	int i, j;
 164	struct ceph_cap *cap;
 165	int have;
 166	int alloc = 0;
 167	int max_caps;
 168	bool trimmed = false;
 169	struct ceph_mds_session *s;
 170	LIST_HEAD(newcaps);
 
 171
 172	dout("reserve caps ctx=%p need=%d\n", ctx, need);
 173
 174	/* first reserve any caps that are already allocated */
 175	spin_lock(&mdsc->caps_list_lock);
 176	if (mdsc->caps_avail_count >= need)
 177		have = need;
 178	else
 179		have = mdsc->caps_avail_count;
 180	mdsc->caps_avail_count -= have;
 181	mdsc->caps_reserve_count += have;
 182	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 183					 mdsc->caps_reserve_count +
 184					 mdsc->caps_avail_count);
 185	spin_unlock(&mdsc->caps_list_lock);
 186
 187	for (i = have; i < need; ) {
 188		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 189		if (cap) {
 190			list_add(&cap->caps_item, &newcaps);
 191			alloc++;
 192			i++;
 193			continue;
 194		}
 195
 196		if (!trimmed) {
 197			for (j = 0; j < mdsc->max_sessions; j++) {
 198				s = __ceph_lookup_mds_session(mdsc, j);
 199				if (!s)
 200					continue;
 201				mutex_unlock(&mdsc->mutex);
 202
 203				mutex_lock(&s->s_mutex);
 204				max_caps = s->s_nr_caps - (need - i);
 205				ceph_trim_caps(mdsc, s, max_caps);
 206				mutex_unlock(&s->s_mutex);
 207
 208				ceph_put_mds_session(s);
 209				mutex_lock(&mdsc->mutex);
 210			}
 211			trimmed = true;
 212
 213			spin_lock(&mdsc->caps_list_lock);
 214			if (mdsc->caps_avail_count) {
 215				int more_have;
 216				if (mdsc->caps_avail_count >= need - i)
 217					more_have = need - i;
 218				else
 219					more_have = mdsc->caps_avail_count;
 220
 221				i += more_have;
 222				have += more_have;
 223				mdsc->caps_avail_count -= more_have;
 224				mdsc->caps_reserve_count += more_have;
 225
 226			}
 227			spin_unlock(&mdsc->caps_list_lock);
 228
 229			continue;
 230		}
 231
 232		pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
 233			ctx, need, have + alloc);
 234		goto out_nomem;
 235	}
 236	BUG_ON(have + alloc != need);
 237
 238	spin_lock(&mdsc->caps_list_lock);
 239	mdsc->caps_total_count += alloc;
 240	mdsc->caps_reserve_count += alloc;
 241	list_splice(&newcaps, &mdsc->caps_list);
 242
 243	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 244					 mdsc->caps_reserve_count +
 245					 mdsc->caps_avail_count);
 246	spin_unlock(&mdsc->caps_list_lock);
 247
 248	ctx->count = need;
 249	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 250	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 251	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 252	return 0;
 253
 254out_nomem:
 255
 256	spin_lock(&mdsc->caps_list_lock);
 257	mdsc->caps_avail_count += have;
 258	mdsc->caps_reserve_count -= have;
 259
 260	while (!list_empty(&newcaps)) {
 261		cap = list_first_entry(&newcaps,
 262				struct ceph_cap, caps_item);
 263		list_del(&cap->caps_item);
 264
 265		/* Keep some preallocated caps around (ceph_min_count), to
 266		 * avoid lots of free/alloc churn. */
 267		if (mdsc->caps_avail_count >=
 268		    mdsc->caps_reserve_count + mdsc->caps_min_count) {
 269			kmem_cache_free(ceph_cap_cachep, cap);
 270		} else {
 271			mdsc->caps_avail_count++;
 272			mdsc->caps_total_count++;
 273			list_add(&cap->caps_item, &mdsc->caps_list);
 274		}
 275	}
 276
 277	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 278					 mdsc->caps_reserve_count +
 279					 mdsc->caps_avail_count);
 280	spin_unlock(&mdsc->caps_list_lock);
 281	return -ENOMEM;
 282}
 283
 284int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 285			struct ceph_cap_reservation *ctx)
 286{
 287	int i;
 288	struct ceph_cap *cap;
 289
 290	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
 291	if (ctx->count) {
 292		spin_lock(&mdsc->caps_list_lock);
 293		BUG_ON(mdsc->caps_reserve_count < ctx->count);
 294		mdsc->caps_reserve_count -= ctx->count;
 295		if (mdsc->caps_avail_count >=
 296		    mdsc->caps_reserve_count + mdsc->caps_min_count) {
 297			mdsc->caps_total_count -= ctx->count;
 298			for (i = 0; i < ctx->count; i++) {
 299				cap = list_first_entry(&mdsc->caps_list,
 300					struct ceph_cap, caps_item);
 301				list_del(&cap->caps_item);
 302				kmem_cache_free(ceph_cap_cachep, cap);
 303			}
 304		} else {
 305			mdsc->caps_avail_count += ctx->count;
 306		}
 307		ctx->count = 0;
 308		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
 309		     mdsc->caps_total_count, mdsc->caps_use_count,
 310		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 311		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 312						 mdsc->caps_reserve_count +
 313						 mdsc->caps_avail_count);
 314		spin_unlock(&mdsc->caps_list_lock);
 315	}
 316	return 0;
 317}
 318
 319struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
 320			      struct ceph_cap_reservation *ctx)
 321{
 322	struct ceph_cap *cap = NULL;
 323
 324	/* temporary, until we do something about cap import/export */
 325	if (!ctx) {
 326		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 327		if (cap) {
 328			spin_lock(&mdsc->caps_list_lock);
 329			mdsc->caps_use_count++;
 330			mdsc->caps_total_count++;
 331			spin_unlock(&mdsc->caps_list_lock);
 332		} else {
 333			spin_lock(&mdsc->caps_list_lock);
 334			if (mdsc->caps_avail_count) {
 335				BUG_ON(list_empty(&mdsc->caps_list));
 336
 337				mdsc->caps_avail_count--;
 338				mdsc->caps_use_count++;
 339				cap = list_first_entry(&mdsc->caps_list,
 340						struct ceph_cap, caps_item);
 341				list_del(&cap->caps_item);
 342
 343				BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 344				       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 345			}
 346			spin_unlock(&mdsc->caps_list_lock);
 347		}
 348
 349		return cap;
 350	}
 351
 352	spin_lock(&mdsc->caps_list_lock);
 353	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
 354	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
 355	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 356	BUG_ON(!ctx->count);
 357	BUG_ON(ctx->count > mdsc->caps_reserve_count);
 358	BUG_ON(list_empty(&mdsc->caps_list));
 359
 360	ctx->count--;
 361	mdsc->caps_reserve_count--;
 362	mdsc->caps_use_count++;
 363
 364	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
 365	list_del(&cap->caps_item);
 366
 367	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 368	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 369	spin_unlock(&mdsc->caps_list_lock);
 370	return cap;
 371}
 372
 373void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
 374{
 375	spin_lock(&mdsc->caps_list_lock);
 376	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
 377	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
 378	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 379	mdsc->caps_use_count--;
 380	/*
 381	 * Keep some preallocated caps around (ceph_min_count), to
 382	 * avoid lots of free/alloc churn.
 383	 */
 384	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
 385				      mdsc->caps_min_count) {
 386		mdsc->caps_total_count--;
 387		kmem_cache_free(ceph_cap_cachep, cap);
 388	} else {
 389		mdsc->caps_avail_count++;
 390		list_add(&cap->caps_item, &mdsc->caps_list);
 391	}
 392
 393	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 394	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 395	spin_unlock(&mdsc->caps_list_lock);
 396}
 397
 398void ceph_reservation_status(struct ceph_fs_client *fsc,
 399			     int *total, int *avail, int *used, int *reserved,
 400			     int *min)
 401{
 402	struct ceph_mds_client *mdsc = fsc->mdsc;
 403
 404	spin_lock(&mdsc->caps_list_lock);
 405
 406	if (total)
 407		*total = mdsc->caps_total_count;
 408	if (avail)
 409		*avail = mdsc->caps_avail_count;
 410	if (used)
 411		*used = mdsc->caps_use_count;
 412	if (reserved)
 413		*reserved = mdsc->caps_reserve_count;
 414	if (min)
 415		*min = mdsc->caps_min_count;
 416
 417	spin_unlock(&mdsc->caps_list_lock);
 418}
 419
 420/*
 421 * Find ceph_cap for given mds, if any.
 422 *
 423 * Called with i_ceph_lock held.
 424 */
 425static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 426{
 427	struct ceph_cap *cap;
 428	struct rb_node *n = ci->i_caps.rb_node;
 429
 430	while (n) {
 431		cap = rb_entry(n, struct ceph_cap, ci_node);
 432		if (mds < cap->mds)
 433			n = n->rb_left;
 434		else if (mds > cap->mds)
 435			n = n->rb_right;
 436		else
 437			return cap;
 438	}
 439	return NULL;
 440}
 441
 442struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 443{
 444	struct ceph_cap *cap;
 445
 446	spin_lock(&ci->i_ceph_lock);
 447	cap = __get_cap_for_mds(ci, mds);
 448	spin_unlock(&ci->i_ceph_lock);
 449	return cap;
 450}
 451
 452/*
 453 * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
 454 */
 455static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
 456{
 457	struct ceph_cap *cap;
 458	int mds = -1;
 459	struct rb_node *p;
 460
 461	/* prefer mds with WR|BUFFER|EXCL caps */
 462	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 463		cap = rb_entry(p, struct ceph_cap, ci_node);
 464		mds = cap->mds;
 465		if (cap->issued & (CEPH_CAP_FILE_WR |
 466				   CEPH_CAP_FILE_BUFFER |
 467				   CEPH_CAP_FILE_EXCL))
 468			break;
 469	}
 470	return mds;
 471}
 472
 473int ceph_get_cap_mds(struct inode *inode)
 474{
 475	struct ceph_inode_info *ci = ceph_inode(inode);
 476	int mds;
 477	spin_lock(&ci->i_ceph_lock);
 478	mds = __ceph_get_cap_mds(ceph_inode(inode));
 479	spin_unlock(&ci->i_ceph_lock);
 480	return mds;
 481}
 482
 483/*
 484 * Called under i_ceph_lock.
 485 */
 486static void __insert_cap_node(struct ceph_inode_info *ci,
 487			      struct ceph_cap *new)
 488{
 489	struct rb_node **p = &ci->i_caps.rb_node;
 490	struct rb_node *parent = NULL;
 491	struct ceph_cap *cap = NULL;
 492
 493	while (*p) {
 494		parent = *p;
 495		cap = rb_entry(parent, struct ceph_cap, ci_node);
 496		if (new->mds < cap->mds)
 497			p = &(*p)->rb_left;
 498		else if (new->mds > cap->mds)
 499			p = &(*p)->rb_right;
 500		else
 501			BUG();
 502	}
 503
 504	rb_link_node(&new->ci_node, parent, p);
 505	rb_insert_color(&new->ci_node, &ci->i_caps);
 506}
 507
 508/*
 509 * (re)set cap hold timeouts, which control the delayed release
 510 * of unused caps back to the MDS.  Should be called on cap use.
 511 */
 512static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
 513			       struct ceph_inode_info *ci)
 514{
 515	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
 516
 517	ci->i_hold_caps_min = round_jiffies(jiffies +
 518					    ma->caps_wanted_delay_min * HZ);
 519	ci->i_hold_caps_max = round_jiffies(jiffies +
 520					    ma->caps_wanted_delay_max * HZ);
 521	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
 522	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
 523}
 524
 525/*
 526 * (Re)queue cap at the end of the delayed cap release list.
 527 *
 528 * If I_FLUSH is set, leave the inode at the front of the list.
 529 *
 530 * Caller holds i_ceph_lock
 531 *    -> we take mdsc->cap_delay_lock
 532 */
 533static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 534				struct ceph_inode_info *ci)
 535{
 536	__cap_set_timeouts(mdsc, ci);
 537	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
 538	     ci->i_ceph_flags, ci->i_hold_caps_max);
 539	if (!mdsc->stopping) {
 540		spin_lock(&mdsc->cap_delay_lock);
 541		if (!list_empty(&ci->i_cap_delay_list)) {
 542			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 543				goto no_change;
 544			list_del_init(&ci->i_cap_delay_list);
 545		}
 546		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 547no_change:
 548		spin_unlock(&mdsc->cap_delay_lock);
 549	}
 550}
 551
 552/*
 553 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 554 * indicating we should send a cap message to flush dirty metadata
 555 * asap, and move to the front of the delayed cap list.
 556 */
 557static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 558				      struct ceph_inode_info *ci)
 559{
 560	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
 561	spin_lock(&mdsc->cap_delay_lock);
 562	ci->i_ceph_flags |= CEPH_I_FLUSH;
 563	if (!list_empty(&ci->i_cap_delay_list))
 564		list_del_init(&ci->i_cap_delay_list);
 565	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 566	spin_unlock(&mdsc->cap_delay_lock);
 567}
 568
 569/*
 570 * Cancel delayed work on cap.
 571 *
 572 * Caller must hold i_ceph_lock.
 573 */
 574static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 575			       struct ceph_inode_info *ci)
 576{
 577	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
 578	if (list_empty(&ci->i_cap_delay_list))
 579		return;
 580	spin_lock(&mdsc->cap_delay_lock);
 581	list_del_init(&ci->i_cap_delay_list);
 582	spin_unlock(&mdsc->cap_delay_lock);
 583}
 584
 585/*
 586 * Common issue checks for add_cap, handle_cap_grant.
 587 */
 588static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 589			      unsigned issued)
 590{
 591	unsigned had = __ceph_caps_issued(ci, NULL);
 592
 593	/*
 594	 * Each time we receive FILE_CACHE anew, we increment
 595	 * i_rdcache_gen.
 596	 */
 597	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 598	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) {
 599		ci->i_rdcache_gen++;
 600	}
 601
 602	/*
 603	 * If FILE_SHARED is newly issued, mark dir not complete. We don't
 604	 * know what happened to this directory while we didn't have the cap.
 605	 * If FILE_SHARED is being revoked, also mark dir not complete. It
 606	 * stops on-going cached readdir.
 607	 */
 608	if ((issued & CEPH_CAP_FILE_SHARED) != (had & CEPH_CAP_FILE_SHARED)) {
 609		if (issued & CEPH_CAP_FILE_SHARED)
 610			atomic_inc(&ci->i_shared_gen);
 611		if (S_ISDIR(ci->vfs_inode.i_mode)) {
 612			dout(" marking %p NOT complete\n", &ci->vfs_inode);
 613			__ceph_dir_clear_complete(ci);
 614		}
 615	}
 616}
 617
 618/*
 619 * Add a capability under the given MDS session.
 620 *
 621 * Caller should hold session snap_rwsem (read) and s_mutex.
 622 *
 623 * @fmode is the open file mode, if we are opening a file, otherwise
 624 * it is < 0.  (This is so we can atomically add the cap and add an
 625 * open file reference to it.)
 626 */
 627void ceph_add_cap(struct inode *inode,
 628		  struct ceph_mds_session *session, u64 cap_id,
 629		  int fmode, unsigned issued, unsigned wanted,
 630		  unsigned seq, unsigned mseq, u64 realmino, int flags,
 631		  struct ceph_cap **new_cap)
 632{
 633	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 634	struct ceph_inode_info *ci = ceph_inode(inode);
 
 635	struct ceph_cap *cap;
 636	int mds = session->s_mds;
 637	int actual_wanted;
 638
 639	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 640	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 641
 642	/*
 643	 * If we are opening the file, include file mode wanted bits
 644	 * in wanted.
 645	 */
 646	if (fmode >= 0)
 647		wanted |= ceph_caps_for_mode(fmode);
 648
 
 
 649	cap = __get_cap_for_mds(ci, mds);
 650	if (!cap) {
 651		cap = *new_cap;
 652		*new_cap = NULL;
 
 
 
 
 
 
 
 
 653
 654		cap->issued = 0;
 655		cap->implemented = 0;
 656		cap->mds = mds;
 657		cap->mds_wanted = 0;
 658		cap->mseq = 0;
 659
 660		cap->ci = ci;
 661		__insert_cap_node(ci, cap);
 662
 
 
 
 
 
 
 
 663		/* add to session cap list */
 664		cap->session = session;
 665		spin_lock(&session->s_cap_lock);
 666		list_add_tail(&cap->session_caps, &session->s_caps);
 667		session->s_nr_caps++;
 668		spin_unlock(&session->s_cap_lock);
 669	} else {
 670		/*
 671		 * auth mds of the inode changed. we received the cap export
 672		 * message, but still haven't received the cap import message.
 673		 * handle_cap_export() updated the new auth MDS' cap.
 674		 *
 675		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 676		 * a message that was send before the cap import message. So
 677		 * don't remove caps.
 678		 */
 679		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 680			WARN_ON(cap != ci->i_auth_cap);
 681			WARN_ON(cap->cap_id != cap_id);
 682			seq = cap->seq;
 683			mseq = cap->mseq;
 684			issued |= cap->issued;
 685			flags |= CEPH_CAP_FLAG_AUTH;
 686		}
 687	}
 688
 689	if (!ci->i_snap_realm ||
 690	    ((flags & CEPH_CAP_FLAG_AUTH) &&
 691	     realmino != (u64)-1 && ci->i_snap_realm->ino != realmino)) {
 692		/*
 693		 * add this inode to the appropriate snap realm
 694		 */
 695		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 696							       realmino);
 697		if (realm) {
 698			struct ceph_snap_realm *oldrealm = ci->i_snap_realm;
 699			if (oldrealm) {
 700				spin_lock(&oldrealm->inodes_with_caps_lock);
 701				list_del_init(&ci->i_snap_realm_item);
 702				spin_unlock(&oldrealm->inodes_with_caps_lock);
 703			}
 704
 705			spin_lock(&realm->inodes_with_caps_lock);
 
 706			list_add(&ci->i_snap_realm_item,
 707				 &realm->inodes_with_caps);
 708			ci->i_snap_realm = realm;
 709			if (realm->ino == ci->i_vino.ino)
 710				realm->inode = inode;
 711			spin_unlock(&realm->inodes_with_caps_lock);
 712
 713			if (oldrealm)
 714				ceph_put_snap_realm(mdsc, oldrealm);
 715		} else {
 716			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 717			       realmino);
 718			WARN_ON(!realm);
 719		}
 720	}
 721
 722	__check_cap_issue(ci, cap, issued);
 723
 724	/*
 725	 * If we are issued caps we don't want, or the mds' wanted
 726	 * value appears to be off, queue a check so we'll release
 727	 * later and/or update the mds wanted value.
 728	 */
 729	actual_wanted = __ceph_caps_wanted(ci);
 730	if ((wanted & ~actual_wanted) ||
 731	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 732		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 733		     ceph_cap_string(issued), ceph_cap_string(wanted),
 734		     ceph_cap_string(actual_wanted));
 735		__cap_delay_requeue(mdsc, ci);
 736	}
 737
 738	if (flags & CEPH_CAP_FLAG_AUTH) {
 739		if (!ci->i_auth_cap ||
 740		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 741			ci->i_auth_cap = cap;
 742			cap->mds_wanted = wanted;
 743		}
 744	} else {
 745		WARN_ON(ci->i_auth_cap == cap);
 746	}
 747
 748	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 749	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 750	     ceph_cap_string(issued|cap->issued), seq, mds);
 751	cap->cap_id = cap_id;
 752	cap->issued = issued;
 753	cap->implemented |= issued;
 754	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 755		cap->mds_wanted = wanted;
 756	else
 757		cap->mds_wanted |= wanted;
 758	cap->seq = seq;
 759	cap->issue_seq = seq;
 760	cap->mseq = mseq;
 761	cap->cap_gen = session->s_cap_gen;
 762
 763	if (fmode >= 0)
 764		__ceph_get_fmode(ci, fmode);
 
 
 
 765}
 766
 767/*
 768 * Return true if cap has not timed out and belongs to the current
 769 * generation of the MDS session (i.e. has not gone 'stale' due to
 770 * us losing touch with the mds).
 771 */
 772static int __cap_is_valid(struct ceph_cap *cap)
 773{
 774	unsigned long ttl;
 775	u32 gen;
 776
 777	spin_lock(&cap->session->s_gen_ttl_lock);
 778	gen = cap->session->s_cap_gen;
 779	ttl = cap->session->s_cap_ttl;
 780	spin_unlock(&cap->session->s_gen_ttl_lock);
 781
 782	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 783		dout("__cap_is_valid %p cap %p issued %s "
 784		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 785		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 786		return 0;
 787	}
 788
 789	return 1;
 790}
 791
 792/*
 793 * Return set of valid cap bits issued to us.  Note that caps time
 794 * out, and may be invalidated in bulk if the client session times out
 795 * and session->s_cap_gen is bumped.
 796 */
 797int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 798{
 799	int have = ci->i_snap_caps;
 800	struct ceph_cap *cap;
 801	struct rb_node *p;
 802
 803	if (implemented)
 804		*implemented = 0;
 805	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 806		cap = rb_entry(p, struct ceph_cap, ci_node);
 807		if (!__cap_is_valid(cap))
 808			continue;
 809		dout("__ceph_caps_issued %p cap %p issued %s\n",
 810		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 811		have |= cap->issued;
 812		if (implemented)
 813			*implemented |= cap->implemented;
 814	}
 815	/*
 816	 * exclude caps issued by non-auth MDS, but are been revoking
 817	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 818	 * these caps, but the message is delayed.
 819	 */
 820	if (ci->i_auth_cap) {
 821		cap = ci->i_auth_cap;
 822		have &= ~cap->implemented | cap->issued;
 823	}
 824	return have;
 825}
 826
 827/*
 828 * Get cap bits issued by caps other than @ocap
 829 */
 830int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 831{
 832	int have = ci->i_snap_caps;
 833	struct ceph_cap *cap;
 834	struct rb_node *p;
 835
 836	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 837		cap = rb_entry(p, struct ceph_cap, ci_node);
 838		if (cap == ocap)
 839			continue;
 840		if (!__cap_is_valid(cap))
 841			continue;
 842		have |= cap->issued;
 843	}
 844	return have;
 845}
 846
 847/*
 848 * Move a cap to the end of the LRU (oldest caps at list head, newest
 849 * at list tail).
 850 */
 851static void __touch_cap(struct ceph_cap *cap)
 852{
 853	struct ceph_mds_session *s = cap->session;
 854
 855	spin_lock(&s->s_cap_lock);
 856	if (!s->s_cap_iterator) {
 857		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 858		     s->s_mds);
 859		list_move_tail(&cap->session_caps, &s->s_caps);
 860	} else {
 861		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 862		     &cap->ci->vfs_inode, cap, s->s_mds);
 863	}
 864	spin_unlock(&s->s_cap_lock);
 865}
 866
 867/*
 868 * Check if we hold the given mask.  If so, move the cap(s) to the
 869 * front of their respective LRUs.  (This is the preferred way for
 870 * callers to check for caps they want.)
 871 */
 872int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 873{
 874	struct ceph_cap *cap;
 875	struct rb_node *p;
 876	int have = ci->i_snap_caps;
 877
 878	if ((have & mask) == mask) {
 879		dout("__ceph_caps_issued_mask %p snap issued %s"
 880		     " (mask %s)\n", &ci->vfs_inode,
 881		     ceph_cap_string(have),
 882		     ceph_cap_string(mask));
 883		return 1;
 884	}
 885
 886	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 887		cap = rb_entry(p, struct ceph_cap, ci_node);
 888		if (!__cap_is_valid(cap))
 889			continue;
 890		if ((cap->issued & mask) == mask) {
 891			dout("__ceph_caps_issued_mask %p cap %p issued %s"
 892			     " (mask %s)\n", &ci->vfs_inode, cap,
 893			     ceph_cap_string(cap->issued),
 894			     ceph_cap_string(mask));
 895			if (touch)
 896				__touch_cap(cap);
 897			return 1;
 898		}
 899
 900		/* does a combination of caps satisfy mask? */
 901		have |= cap->issued;
 902		if ((have & mask) == mask) {
 903			dout("__ceph_caps_issued_mask %p combo issued %s"
 904			     " (mask %s)\n", &ci->vfs_inode,
 905			     ceph_cap_string(cap->issued),
 906			     ceph_cap_string(mask));
 907			if (touch) {
 908				struct rb_node *q;
 909
 910				/* touch this + preceding caps */
 911				__touch_cap(cap);
 912				for (q = rb_first(&ci->i_caps); q != p;
 913				     q = rb_next(q)) {
 914					cap = rb_entry(q, struct ceph_cap,
 915						       ci_node);
 916					if (!__cap_is_valid(cap))
 917						continue;
 918					__touch_cap(cap);
 919				}
 920			}
 921			return 1;
 922		}
 923	}
 924
 925	return 0;
 926}
 927
 928/*
 929 * Return true if mask caps are currently being revoked by an MDS.
 930 */
 931int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 932			       struct ceph_cap *ocap, int mask)
 933{
 
 934	struct ceph_cap *cap;
 935	struct rb_node *p;
 
 936
 
 937	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 938		cap = rb_entry(p, struct ceph_cap, ci_node);
 939		if (cap != ocap &&
 940		    (cap->implemented & ~cap->issued & mask))
 941			return 1;
 
 
 942	}
 943	return 0;
 944}
 945
 946int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 947{
 948	struct inode *inode = &ci->vfs_inode;
 949	int ret;
 950
 951	spin_lock(&ci->i_ceph_lock);
 952	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 953	spin_unlock(&ci->i_ceph_lock);
 954	dout("ceph_caps_revoking %p %s = %d\n", inode,
 955	     ceph_cap_string(mask), ret);
 956	return ret;
 957}
 958
 959int __ceph_caps_used(struct ceph_inode_info *ci)
 960{
 961	int used = 0;
 962	if (ci->i_pin_ref)
 963		used |= CEPH_CAP_PIN;
 964	if (ci->i_rd_ref)
 965		used |= CEPH_CAP_FILE_RD;
 966	if (ci->i_rdcache_ref ||
 967	    (!S_ISDIR(ci->vfs_inode.i_mode) && /* ignore readdir cache */
 968	     ci->vfs_inode.i_data.nrpages))
 969		used |= CEPH_CAP_FILE_CACHE;
 970	if (ci->i_wr_ref)
 971		used |= CEPH_CAP_FILE_WR;
 972	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 973		used |= CEPH_CAP_FILE_BUFFER;
 974	return used;
 975}
 976
 977/*
 978 * wanted, by virtue of open file modes
 979 */
 980int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 981{
 982	int i, bits = 0;
 983	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
 984		if (ci->i_nr_by_mode[i])
 985			bits |= 1 << i;
 986	}
 987	if (bits == 0)
 988		return 0;
 989	return ceph_caps_for_mode(bits >> 1);
 990}
 991
 992/*
 993 * Return caps we have registered with the MDS(s) as 'wanted'.
 994 */
 995int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check)
 996{
 997	struct ceph_cap *cap;
 998	struct rb_node *p;
 999	int mds_wanted = 0;
1000
1001	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1002		cap = rb_entry(p, struct ceph_cap, ci_node);
1003		if (check && !__cap_is_valid(cap))
1004			continue;
1005		if (cap == ci->i_auth_cap)
1006			mds_wanted |= cap->mds_wanted;
1007		else
1008			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
1009	}
1010	return mds_wanted;
1011}
1012
1013/*
1014 * called under i_ceph_lock
1015 */
1016static int __ceph_is_single_caps(struct ceph_inode_info *ci)
1017{
1018	return rb_first(&ci->i_caps) == rb_last(&ci->i_caps);
1019}
1020
1021static int __ceph_is_any_caps(struct ceph_inode_info *ci)
1022{
1023	return !RB_EMPTY_ROOT(&ci->i_caps);
1024}
1025
1026int ceph_is_any_caps(struct inode *inode)
1027{
1028	struct ceph_inode_info *ci = ceph_inode(inode);
1029	int ret;
1030
1031	spin_lock(&ci->i_ceph_lock);
1032	ret = __ceph_is_any_caps(ci);
1033	spin_unlock(&ci->i_ceph_lock);
1034
1035	return ret;
1036}
1037
1038static void drop_inode_snap_realm(struct ceph_inode_info *ci)
1039{
1040	struct ceph_snap_realm *realm = ci->i_snap_realm;
1041	spin_lock(&realm->inodes_with_caps_lock);
1042	list_del_init(&ci->i_snap_realm_item);
1043	ci->i_snap_realm_counter++;
1044	ci->i_snap_realm = NULL;
1045	spin_unlock(&realm->inodes_with_caps_lock);
1046	ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc,
1047			    realm);
1048}
1049
1050/*
1051 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
1052 *
1053 * caller should hold i_ceph_lock.
1054 * caller will not hold session s_mutex if called from destroy_inode.
1055 */
1056void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
1057{
1058	struct ceph_mds_session *session = cap->session;
1059	struct ceph_inode_info *ci = cap->ci;
1060	struct ceph_mds_client *mdsc =
1061		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1062	int removed = 0;
1063
1064	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
1065
1066	/* remove from session list */
1067	spin_lock(&session->s_cap_lock);
1068	if (session->s_cap_iterator == cap) {
1069		/* not yet, we are iterating over this very cap */
1070		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
1071		     cap, cap->session);
1072	} else {
1073		list_del_init(&cap->session_caps);
1074		session->s_nr_caps--;
1075		cap->session = NULL;
1076		removed = 1;
1077	}
1078	/* protect backpointer with s_cap_lock: see iterate_session_caps */
1079	cap->ci = NULL;
1080
1081	/*
1082	 * s_cap_reconnect is protected by s_cap_lock. no one changes
1083	 * s_cap_gen while session is in the reconnect state.
1084	 */
1085	if (queue_release &&
1086	    (!session->s_cap_reconnect || cap->cap_gen == session->s_cap_gen)) {
1087		cap->queue_release = 1;
1088		if (removed) {
1089			list_add_tail(&cap->session_caps,
1090				      &session->s_cap_releases);
1091			session->s_num_cap_releases++;
1092			removed = 0;
1093		}
1094	} else {
1095		cap->queue_release = 0;
1096	}
1097	cap->cap_ino = ci->i_vino.ino;
1098
1099	spin_unlock(&session->s_cap_lock);
1100
1101	/* remove from inode list */
1102	rb_erase(&cap->ci_node, &ci->i_caps);
1103	if (ci->i_auth_cap == cap)
1104		ci->i_auth_cap = NULL;
1105
1106	if (removed)
1107		ceph_put_cap(mdsc, cap);
1108
1109	/* when reconnect denied, we remove session caps forcibly,
1110	 * i_wr_ref can be non-zero. If there are ongoing write,
1111	 * keep i_snap_realm.
1112	 */
1113	if (!__ceph_is_any_caps(ci) && ci->i_wr_ref == 0 && ci->i_snap_realm)
1114		drop_inode_snap_realm(ci);
1115
 
 
1116	if (!__ceph_is_any_real_caps(ci))
1117		__cap_delay_cancel(mdsc, ci);
1118}
1119
1120struct cap_msg_args {
1121	struct ceph_mds_session	*session;
1122	u64			ino, cid, follows;
1123	u64			flush_tid, oldest_flush_tid, size, max_size;
1124	u64			xattr_version;
1125	struct ceph_buffer	*xattr_buf;
1126	struct timespec		atime, mtime, ctime;
1127	int			op, caps, wanted, dirty;
1128	u32			seq, issue_seq, mseq, time_warp_seq;
1129	u32			flags;
1130	kuid_t			uid;
1131	kgid_t			gid;
1132	umode_t			mode;
1133	bool			inline_data;
1134};
1135
1136/*
1137 * Build and send a cap message to the given MDS.
1138 *
1139 * Caller should be holding s_mutex.
1140 */
1141static int send_cap_msg(struct cap_msg_args *arg)
 
 
 
 
 
 
 
 
 
 
1142{
1143	struct ceph_mds_caps *fc;
1144	struct ceph_msg *msg;
1145	void *p;
1146	size_t extra_len;
1147	struct timespec zerotime = {0};
1148	struct ceph_osd_client *osdc = &arg->session->s_mdsc->fsc->client->osdc;
1149
1150	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
1151	     " seq %u/%u tid %llu/%llu mseq %u follows %lld size %llu/%llu"
1152	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(arg->op),
1153	     arg->cid, arg->ino, ceph_cap_string(arg->caps),
1154	     ceph_cap_string(arg->wanted), ceph_cap_string(arg->dirty),
1155	     arg->seq, arg->issue_seq, arg->flush_tid, arg->oldest_flush_tid,
1156	     arg->mseq, arg->follows, arg->size, arg->max_size,
1157	     arg->xattr_version,
1158	     arg->xattr_buf ? (int)arg->xattr_buf->vec.iov_len : 0);
1159
1160	/* flock buffer size + inline version + inline data size +
1161	 * osd_epoch_barrier + oldest_flush_tid */
1162	extra_len = 4 + 8 + 4 + 4 + 8 + 4 + 4 + 4 + 8 + 8 + 4;
1163	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc) + extra_len,
1164			   GFP_NOFS, false);
1165	if (!msg)
1166		return -ENOMEM;
1167
1168	msg->hdr.version = cpu_to_le16(10);
1169	msg->hdr.tid = cpu_to_le64(arg->flush_tid);
1170
1171	fc = msg->front.iov_base;
1172	memset(fc, 0, sizeof(*fc));
1173
1174	fc->cap_id = cpu_to_le64(arg->cid);
1175	fc->op = cpu_to_le32(arg->op);
1176	fc->seq = cpu_to_le32(arg->seq);
1177	fc->issue_seq = cpu_to_le32(arg->issue_seq);
1178	fc->migrate_seq = cpu_to_le32(arg->mseq);
1179	fc->caps = cpu_to_le32(arg->caps);
1180	fc->wanted = cpu_to_le32(arg->wanted);
1181	fc->dirty = cpu_to_le32(arg->dirty);
1182	fc->ino = cpu_to_le64(arg->ino);
1183	fc->snap_follows = cpu_to_le64(arg->follows);
1184
1185	fc->size = cpu_to_le64(arg->size);
1186	fc->max_size = cpu_to_le64(arg->max_size);
1187	ceph_encode_timespec(&fc->mtime, &arg->mtime);
1188	ceph_encode_timespec(&fc->atime, &arg->atime);
1189	ceph_encode_timespec(&fc->ctime, &arg->ctime);
1190	fc->time_warp_seq = cpu_to_le32(arg->time_warp_seq);
1191
1192	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, arg->uid));
1193	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, arg->gid));
1194	fc->mode = cpu_to_le32(arg->mode);
1195
1196	fc->xattr_version = cpu_to_le64(arg->xattr_version);
1197	if (arg->xattr_buf) {
1198		msg->middle = ceph_buffer_get(arg->xattr_buf);
1199		fc->xattr_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1200		msg->hdr.middle_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1201	}
1202
1203	p = fc + 1;
1204	/* flock buffer size (version 2) */
1205	ceph_encode_32(&p, 0);
1206	/* inline version (version 4) */
1207	ceph_encode_64(&p, arg->inline_data ? 0 : CEPH_INLINE_NONE);
1208	/* inline data size */
1209	ceph_encode_32(&p, 0);
1210	/*
1211	 * osd_epoch_barrier (version 5)
1212	 * The epoch_barrier is protected osdc->lock, so READ_ONCE here in
1213	 * case it was recently changed
1214	 */
1215	ceph_encode_32(&p, READ_ONCE(osdc->epoch_barrier));
1216	/* oldest_flush_tid (version 6) */
1217	ceph_encode_64(&p, arg->oldest_flush_tid);
1218
1219	/*
1220	 * caller_uid/caller_gid (version 7)
1221	 *
1222	 * Currently, we don't properly track which caller dirtied the caps
1223	 * last, and force a flush of them when there is a conflict. For now,
1224	 * just set this to 0:0, to emulate how the MDS has worked up to now.
1225	 */
1226	ceph_encode_32(&p, 0);
1227	ceph_encode_32(&p, 0);
1228
1229	/* pool namespace (version 8) (mds always ignores this) */
1230	ceph_encode_32(&p, 0);
1231
1232	/*
1233	 * btime and change_attr (version 9)
1234	 *
1235	 * We just zero these out for now, as the MDS ignores them unless
1236	 * the requisite feature flags are set (which we don't do yet).
1237	 */
1238	ceph_encode_timespec(p, &zerotime);
1239	p += sizeof(struct ceph_timespec);
1240	ceph_encode_64(&p, 0);
1241
1242	/* Advisory flags (version 10) */
1243	ceph_encode_32(&p, arg->flags);
 
 
 
 
 
1244
1245	ceph_con_send(&arg->session->s_con, msg);
1246	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1247}
1248
1249/*
1250 * Queue cap releases when an inode is dropped from our cache.  Since
1251 * inode is about to be destroyed, there is no need for i_ceph_lock.
1252 */
1253void ceph_queue_caps_release(struct inode *inode)
1254{
1255	struct ceph_inode_info *ci = ceph_inode(inode);
1256	struct rb_node *p;
1257
1258	p = rb_first(&ci->i_caps);
1259	while (p) {
1260		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
 
 
 
 
1261		p = rb_next(p);
1262		__ceph_remove_cap(cap, true);
1263	}
1264}
1265
1266/*
1267 * Send a cap msg on the given inode.  Update our caps state, then
1268 * drop i_ceph_lock and send the message.
1269 *
1270 * Make note of max_size reported/requested from mds, revoked caps
1271 * that have now been implemented.
1272 *
1273 * Make half-hearted attempt ot to invalidate page cache if we are
1274 * dropping RDCACHE.  Note that this will leave behind locked pages
1275 * that we'll then need to deal with elsewhere.
1276 *
1277 * Return non-zero if delayed release, or we experienced an error
1278 * such that the caller should requeue + retry later.
1279 *
1280 * called with i_ceph_lock, then drops it.
1281 * caller should hold snap_rwsem (read), s_mutex.
1282 */
1283static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1284		      int op, bool sync, int used, int want, int retain,
1285		      int flushing, u64 flush_tid, u64 oldest_flush_tid)
1286	__releases(cap->ci->i_ceph_lock)
1287{
1288	struct ceph_inode_info *ci = cap->ci;
1289	struct inode *inode = &ci->vfs_inode;
1290	struct cap_msg_args arg;
1291	int held, revoking;
 
 
 
1292	int wake = 0;
 
 
 
 
 
 
1293	int delayed = 0;
 
 
1294	int ret;
1295
1296	held = cap->issued | cap->implemented;
1297	revoking = cap->implemented & ~cap->issued;
1298	retain &= ~revoking;
 
1299
1300	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1301	     inode, cap, cap->session,
1302	     ceph_cap_string(held), ceph_cap_string(held & retain),
1303	     ceph_cap_string(revoking));
1304	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1305
1306	arg.session = cap->session;
1307
1308	/* don't release wanted unless we've waited a bit. */
1309	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1310	    time_before(jiffies, ci->i_hold_caps_min)) {
1311		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1312		     ceph_cap_string(cap->issued),
1313		     ceph_cap_string(cap->issued & retain),
1314		     ceph_cap_string(cap->mds_wanted),
1315		     ceph_cap_string(want));
1316		want |= cap->mds_wanted;
1317		retain |= cap->issued;
1318		delayed = 1;
1319	}
1320	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1321	if (want & ~cap->mds_wanted) {
1322		/* user space may open/close single file frequently.
1323		 * This avoids droping mds_wanted immediately after
1324		 * requesting new mds_wanted.
1325		 */
1326		__cap_set_timeouts(mdsc, ci);
1327	}
1328
1329	cap->issued &= retain;  /* drop bits we don't want */
1330	if (cap->implemented & ~cap->issued) {
1331		/*
1332		 * Wake up any waiters on wanted -> needed transition.
1333		 * This is due to the weird transition from buffered
1334		 * to sync IO... we need to flush dirty pages _before_
1335		 * allowing sync writes to avoid reordering.
1336		 */
1337		wake = 1;
1338	}
1339	cap->implemented &= cap->issued | used;
1340	cap->mds_wanted = want;
1341
1342	arg.ino = ceph_vino(inode).ino;
1343	arg.cid = cap->cap_id;
1344	arg.follows = flushing ? ci->i_head_snapc->seq : 0;
1345	arg.flush_tid = flush_tid;
1346	arg.oldest_flush_tid = oldest_flush_tid;
1347
1348	arg.size = inode->i_size;
1349	ci->i_reported_size = arg.size;
1350	arg.max_size = ci->i_wanted_max_size;
1351	ci->i_requested_max_size = arg.max_size;
 
 
 
 
 
1352
1353	if (flushing & CEPH_CAP_XATTR_EXCL) {
1354		__ceph_build_xattrs_blob(ci);
1355		arg.xattr_version = ci->i_xattrs.version;
1356		arg.xattr_buf = ci->i_xattrs.blob;
1357	} else {
1358		arg.xattr_buf = NULL;
1359	}
1360
1361	arg.mtime = inode->i_mtime;
1362	arg.atime = inode->i_atime;
1363	arg.ctime = inode->i_ctime;
1364
1365	arg.op = op;
1366	arg.caps = cap->implemented;
1367	arg.wanted = want;
1368	arg.dirty = flushing;
1369
1370	arg.seq = cap->seq;
1371	arg.issue_seq = cap->issue_seq;
1372	arg.mseq = cap->mseq;
1373	arg.time_warp_seq = ci->i_time_warp_seq;
1374
1375	arg.uid = inode->i_uid;
1376	arg.gid = inode->i_gid;
1377	arg.mode = inode->i_mode;
1378
1379	arg.inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1380	if (list_empty(&ci->i_cap_snaps))
1381		arg.flags = CEPH_CLIENT_CAPS_NO_CAPSNAP;
1382	else
1383		arg.flags = CEPH_CLIENT_CAPS_PENDING_CAPSNAP;
1384	if (sync)
1385		arg.flags |= CEPH_CLIENT_CAPS_SYNC;
1386
1387	spin_unlock(&ci->i_ceph_lock);
1388
1389	ret = send_cap_msg(&arg);
 
 
 
 
1390	if (ret < 0) {
1391		dout("error sending cap msg, must requeue %p\n", inode);
1392		delayed = 1;
1393	}
1394
1395	if (wake)
1396		wake_up_all(&ci->i_cap_wq);
1397
1398	return delayed;
1399}
1400
1401static inline int __send_flush_snap(struct inode *inode,
1402				    struct ceph_mds_session *session,
1403				    struct ceph_cap_snap *capsnap,
1404				    u32 mseq, u64 oldest_flush_tid)
1405{
1406	struct cap_msg_args	arg;
1407
1408	arg.session = session;
1409	arg.ino = ceph_vino(inode).ino;
1410	arg.cid = 0;
1411	arg.follows = capsnap->follows;
1412	arg.flush_tid = capsnap->cap_flush.tid;
1413	arg.oldest_flush_tid = oldest_flush_tid;
1414
1415	arg.size = capsnap->size;
1416	arg.max_size = 0;
1417	arg.xattr_version = capsnap->xattr_version;
1418	arg.xattr_buf = capsnap->xattr_blob;
1419
1420	arg.atime = capsnap->atime;
1421	arg.mtime = capsnap->mtime;
1422	arg.ctime = capsnap->ctime;
1423
1424	arg.op = CEPH_CAP_OP_FLUSHSNAP;
1425	arg.caps = capsnap->issued;
1426	arg.wanted = 0;
1427	arg.dirty = capsnap->dirty;
1428
1429	arg.seq = 0;
1430	arg.issue_seq = 0;
1431	arg.mseq = mseq;
1432	arg.time_warp_seq = capsnap->time_warp_seq;
1433
1434	arg.uid = capsnap->uid;
1435	arg.gid = capsnap->gid;
1436	arg.mode = capsnap->mode;
1437
1438	arg.inline_data = capsnap->inline_data;
1439	arg.flags = 0;
1440
1441	return send_cap_msg(&arg);
1442}
1443
1444/*
1445 * When a snapshot is taken, clients accumulate dirty metadata on
1446 * inodes with capabilities in ceph_cap_snaps to describe the file
1447 * state at the time the snapshot was taken.  This must be flushed
1448 * asynchronously back to the MDS once sync writes complete and dirty
1449 * data is written out.
1450 *
 
 
 
1451 * Called under i_ceph_lock.  Takes s_mutex as needed.
1452 */
1453static void __ceph_flush_snaps(struct ceph_inode_info *ci,
1454			       struct ceph_mds_session *session)
 
1455		__releases(ci->i_ceph_lock)
1456		__acquires(ci->i_ceph_lock)
1457{
1458	struct inode *inode = &ci->vfs_inode;
1459	struct ceph_mds_client *mdsc = session->s_mdsc;
1460	struct ceph_cap_snap *capsnap;
1461	u64 oldest_flush_tid = 0;
1462	u64 first_tid = 1, last_tid = 0;
 
 
 
 
 
1463
1464	dout("__flush_snaps %p session %p\n", inode, session);
 
1465
 
 
1466	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 
 
 
1467		/*
1468		 * we need to wait for sync writes to complete and for dirty
1469		 * pages to be written out.
1470		 */
1471		if (capsnap->dirty_pages || capsnap->writing)
1472			break;
1473
1474		/* should be removed by ceph_try_drop_cap_snap() */
1475		BUG_ON(!capsnap->need_flush);
 
 
 
 
 
 
 
 
 
1476
1477		/* only flush each capsnap once */
1478		if (capsnap->cap_flush.tid > 0) {
1479			dout(" already flushed %p, skipping\n", capsnap);
1480			continue;
1481		}
1482
1483		spin_lock(&mdsc->cap_dirty_lock);
1484		capsnap->cap_flush.tid = ++mdsc->last_cap_flush_tid;
1485		list_add_tail(&capsnap->cap_flush.g_list,
1486			      &mdsc->cap_flush_list);
1487		if (oldest_flush_tid == 0)
1488			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1489		if (list_empty(&ci->i_flushing_item)) {
1490			list_add_tail(&ci->i_flushing_item,
1491				      &session->s_cap_flushing);
1492		}
1493		spin_unlock(&mdsc->cap_dirty_lock);
1494
1495		list_add_tail(&capsnap->cap_flush.i_list,
1496			      &ci->i_cap_flush_list);
1497
1498		if (first_tid == 1)
1499			first_tid = capsnap->cap_flush.tid;
1500		last_tid = capsnap->cap_flush.tid;
1501	}
1502
1503	ci->i_ceph_flags &= ~CEPH_I_FLUSH_SNAPS;
1504
1505	while (first_tid <= last_tid) {
1506		struct ceph_cap *cap = ci->i_auth_cap;
1507		struct ceph_cap_flush *cf;
1508		int ret;
1509
1510		if (!(cap && cap->session == session)) {
1511			dout("__flush_snaps %p auth cap %p not mds%d, "
1512			     "stop\n", inode, cap, session->s_mds);
1513			break;
 
1514		}
1515
1516		ret = -ENOENT;
1517		list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
1518			if (cf->tid >= first_tid) {
1519				ret = 0;
1520				break;
 
 
 
1521			}
 
 
 
 
 
 
 
1522		}
1523		if (ret < 0)
1524			break;
1525
1526		first_tid = cf->tid + 1;
1527
1528		capsnap = container_of(cf, struct ceph_cap_snap, cap_flush);
1529		refcount_inc(&capsnap->nref);
 
 
1530		spin_unlock(&ci->i_ceph_lock);
1531
1532		dout("__flush_snaps %p capsnap %p tid %llu %s\n",
1533		     inode, capsnap, cf->tid, ceph_cap_string(capsnap->dirty));
1534
1535		ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
1536					oldest_flush_tid);
1537		if (ret < 0) {
1538			pr_err("__flush_snaps: error sending cap flushsnap, "
1539			       "ino (%llx.%llx) tid %llu follows %llu\n",
1540				ceph_vinop(inode), cf->tid, capsnap->follows);
1541		}
 
1542
 
1543		ceph_put_cap_snap(capsnap);
1544		spin_lock(&ci->i_ceph_lock);
1545	}
1546}
1547
1548void ceph_flush_snaps(struct ceph_inode_info *ci,
1549		      struct ceph_mds_session **psession)
1550{
1551	struct inode *inode = &ci->vfs_inode;
1552	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1553	struct ceph_mds_session *session = NULL;
1554	int mds;
1555
1556	dout("ceph_flush_snaps %p\n", inode);
1557	if (psession)
1558		session = *psession;
1559retry:
1560	spin_lock(&ci->i_ceph_lock);
1561	if (!(ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)) {
1562		dout(" no capsnap needs flush, doing nothing\n");
1563		goto out;
1564	}
1565	if (!ci->i_auth_cap) {
1566		dout(" no auth cap (migrating?), doing nothing\n");
1567		goto out;
1568	}
1569
1570	mds = ci->i_auth_cap->session->s_mds;
1571	if (session && session->s_mds != mds) {
1572		dout(" oops, wrong session %p mutex\n", session);
1573		mutex_unlock(&session->s_mutex);
1574		ceph_put_mds_session(session);
1575		session = NULL;
1576	}
1577	if (!session) {
1578		spin_unlock(&ci->i_ceph_lock);
1579		mutex_lock(&mdsc->mutex);
1580		session = __ceph_lookup_mds_session(mdsc, mds);
1581		mutex_unlock(&mdsc->mutex);
1582		if (session) {
1583			dout(" inverting session/ino locks on %p\n", session);
1584			mutex_lock(&session->s_mutex);
1585		}
1586		goto retry;
1587	}
1588
1589	// make sure flushsnap messages are sent in proper order.
1590	if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
1591		__kick_flushing_caps(mdsc, session, ci, 0);
1592		ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
1593	}
1594
1595	__ceph_flush_snaps(ci, session);
1596out:
1597	spin_unlock(&ci->i_ceph_lock);
1598
1599	if (psession) {
1600		*psession = session;
1601	} else if (session) {
1602		mutex_unlock(&session->s_mutex);
1603		ceph_put_mds_session(session);
1604	}
1605	/* we flushed them all; remove this inode from the queue */
1606	spin_lock(&mdsc->snap_flush_lock);
1607	list_del_init(&ci->i_snap_flush_item);
1608	spin_unlock(&mdsc->snap_flush_lock);
 
 
 
1609}
1610
1611/*
1612 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1613 * Caller is then responsible for calling __mark_inode_dirty with the
1614 * returned flags value.
1615 */
1616int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask,
1617			   struct ceph_cap_flush **pcf)
1618{
1619	struct ceph_mds_client *mdsc =
1620		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1621	struct inode *inode = &ci->vfs_inode;
1622	int was = ci->i_dirty_caps;
1623	int dirty = 0;
1624
1625	if (!ci->i_auth_cap) {
1626		pr_warn("__mark_dirty_caps %p %llx mask %s, "
1627			"but no auth cap (session was closed?)\n",
1628			inode, ceph_ino(inode), ceph_cap_string(mask));
1629		return 0;
1630	}
1631
1632	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1633	     ceph_cap_string(mask), ceph_cap_string(was),
1634	     ceph_cap_string(was | mask));
1635	ci->i_dirty_caps |= mask;
1636	if (was == 0) {
1637		WARN_ON_ONCE(ci->i_prealloc_cap_flush);
1638		swap(ci->i_prealloc_cap_flush, *pcf);
1639
1640		if (!ci->i_head_snapc) {
1641			WARN_ON_ONCE(!rwsem_is_locked(&mdsc->snap_rwsem));
1642			ci->i_head_snapc = ceph_get_snap_context(
1643				ci->i_snap_realm->cached_context);
1644		}
1645		dout(" inode %p now dirty snapc %p auth cap %p\n",
1646		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
1647		BUG_ON(!list_empty(&ci->i_dirty_item));
1648		spin_lock(&mdsc->cap_dirty_lock);
1649		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1650		spin_unlock(&mdsc->cap_dirty_lock);
1651		if (ci->i_flushing_caps == 0) {
1652			ihold(inode);
1653			dirty |= I_DIRTY_SYNC;
1654		}
1655	} else {
1656		WARN_ON_ONCE(!ci->i_prealloc_cap_flush);
1657	}
1658	BUG_ON(list_empty(&ci->i_dirty_item));
1659	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1660	    (mask & CEPH_CAP_FILE_BUFFER))
1661		dirty |= I_DIRTY_DATASYNC;
1662	__cap_delay_requeue(mdsc, ci);
1663	return dirty;
1664}
1665
1666struct ceph_cap_flush *ceph_alloc_cap_flush(void)
1667{
1668	return kmem_cache_alloc(ceph_cap_flush_cachep, GFP_KERNEL);
1669}
1670
1671void ceph_free_cap_flush(struct ceph_cap_flush *cf)
1672{
1673	if (cf)
1674		kmem_cache_free(ceph_cap_flush_cachep, cf);
1675}
1676
1677static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc)
1678{
1679	if (!list_empty(&mdsc->cap_flush_list)) {
1680		struct ceph_cap_flush *cf =
1681			list_first_entry(&mdsc->cap_flush_list,
1682					 struct ceph_cap_flush, g_list);
1683		return cf->tid;
1684	}
1685	return 0;
1686}
1687
1688/*
1689 * Remove cap_flush from the mdsc's or inode's flushing cap list.
1690 * Return true if caller needs to wake up flush waiters.
1691 */
1692static bool __finish_cap_flush(struct ceph_mds_client *mdsc,
1693			       struct ceph_inode_info *ci,
1694			       struct ceph_cap_flush *cf)
1695{
1696	struct ceph_cap_flush *prev;
1697	bool wake = cf->wake;
1698	if (mdsc) {
1699		/* are there older pending cap flushes? */
1700		if (wake && cf->g_list.prev != &mdsc->cap_flush_list) {
1701			prev = list_prev_entry(cf, g_list);
1702			prev->wake = true;
1703			wake = false;
1704		}
1705		list_del(&cf->g_list);
1706	} else if (ci) {
1707		if (wake && cf->i_list.prev != &ci->i_cap_flush_list) {
1708			prev = list_prev_entry(cf, i_list);
1709			prev->wake = true;
1710			wake = false;
1711		}
1712		list_del(&cf->i_list);
1713	} else {
1714		BUG_ON(1);
1715	}
1716	return wake;
1717}
1718
1719/*
1720 * Add dirty inode to the flushing list.  Assigned a seq number so we
1721 * can wait for caps to flush without starving.
1722 *
1723 * Called under i_ceph_lock.
1724 */
1725static int __mark_caps_flushing(struct inode *inode,
1726				struct ceph_mds_session *session, bool wake,
1727				u64 *flush_tid, u64 *oldest_flush_tid)
1728{
1729	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1730	struct ceph_inode_info *ci = ceph_inode(inode);
1731	struct ceph_cap_flush *cf = NULL;
1732	int flushing;
1733
1734	BUG_ON(ci->i_dirty_caps == 0);
1735	BUG_ON(list_empty(&ci->i_dirty_item));
1736	BUG_ON(!ci->i_prealloc_cap_flush);
1737
1738	flushing = ci->i_dirty_caps;
1739	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1740	     ceph_cap_string(flushing),
1741	     ceph_cap_string(ci->i_flushing_caps),
1742	     ceph_cap_string(ci->i_flushing_caps | flushing));
1743	ci->i_flushing_caps |= flushing;
1744	ci->i_dirty_caps = 0;
1745	dout(" inode %p now !dirty\n", inode);
1746
1747	swap(cf, ci->i_prealloc_cap_flush);
1748	cf->caps = flushing;
1749	cf->wake = wake;
1750
1751	spin_lock(&mdsc->cap_dirty_lock);
1752	list_del_init(&ci->i_dirty_item);
1753
1754	cf->tid = ++mdsc->last_cap_flush_tid;
1755	list_add_tail(&cf->g_list, &mdsc->cap_flush_list);
1756	*oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1757
1758	if (list_empty(&ci->i_flushing_item)) {
1759		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1760		mdsc->num_cap_flushing++;
 
 
 
 
 
 
1761	}
1762	spin_unlock(&mdsc->cap_dirty_lock);
1763
1764	list_add_tail(&cf->i_list, &ci->i_cap_flush_list);
1765
1766	*flush_tid = cf->tid;
1767	return flushing;
1768}
1769
1770/*
1771 * try to invalidate mapping pages without blocking.
1772 */
1773static int try_nonblocking_invalidate(struct inode *inode)
1774{
1775	struct ceph_inode_info *ci = ceph_inode(inode);
1776	u32 invalidating_gen = ci->i_rdcache_gen;
1777
1778	spin_unlock(&ci->i_ceph_lock);
1779	invalidate_mapping_pages(&inode->i_data, 0, -1);
1780	spin_lock(&ci->i_ceph_lock);
1781
1782	if (inode->i_data.nrpages == 0 &&
1783	    invalidating_gen == ci->i_rdcache_gen) {
1784		/* success. */
1785		dout("try_nonblocking_invalidate %p success\n", inode);
1786		/* save any racing async invalidate some trouble */
1787		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1788		return 0;
1789	}
1790	dout("try_nonblocking_invalidate %p failed\n", inode);
1791	return -1;
1792}
1793
1794bool __ceph_should_report_size(struct ceph_inode_info *ci)
1795{
1796	loff_t size = ci->vfs_inode.i_size;
1797	/* mds will adjust max size according to the reported size */
1798	if (ci->i_flushing_caps & CEPH_CAP_FILE_WR)
1799		return false;
1800	if (size >= ci->i_max_size)
1801		return true;
1802	/* half of previous max_size increment has been used */
1803	if (ci->i_max_size > ci->i_reported_size &&
1804	    (size << 1) >= ci->i_max_size + ci->i_reported_size)
1805		return true;
1806	return false;
1807}
1808
1809/*
1810 * Swiss army knife function to examine currently used and wanted
1811 * versus held caps.  Release, flush, ack revoked caps to mds as
1812 * appropriate.
1813 *
1814 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1815 *    cap release further.
1816 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1817 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1818 *    further delay.
1819 */
1820void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1821		     struct ceph_mds_session *session)
1822{
1823	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1824	struct ceph_mds_client *mdsc = fsc->mdsc;
1825	struct inode *inode = &ci->vfs_inode;
1826	struct ceph_cap *cap;
1827	u64 flush_tid, oldest_flush_tid;
1828	int file_wanted, used, cap_used;
1829	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1830	int issued, implemented, want, retain, revoking, flushing = 0;
1831	int mds = -1;   /* keep track of how far we've gone through i_caps list
1832			   to avoid an infinite loop on retry */
1833	struct rb_node *p;
1834	int delayed = 0, sent = 0;
1835	bool no_delay = flags & CHECK_CAPS_NODELAY;
1836	bool queue_invalidate = false;
1837	bool tried_invalidate = false;
1838
1839	/* if we are unmounting, flush any unused caps immediately. */
1840	if (mdsc->stopping)
1841		no_delay = true;
1842
1843	spin_lock(&ci->i_ceph_lock);
1844
1845	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1846		flags |= CHECK_CAPS_FLUSH;
1847
1848	if (!(flags & CHECK_CAPS_AUTHONLY) ||
1849	    (ci->i_auth_cap && __ceph_is_single_caps(ci)))
1850		__cap_delay_cancel(mdsc, ci);
1851
1852	goto retry_locked;
1853retry:
1854	spin_lock(&ci->i_ceph_lock);
1855retry_locked:
1856	file_wanted = __ceph_caps_file_wanted(ci);
1857	used = __ceph_caps_used(ci);
 
1858	issued = __ceph_caps_issued(ci, &implemented);
1859	revoking = implemented & ~issued;
1860
1861	want = file_wanted;
1862	retain = file_wanted | used | CEPH_CAP_PIN;
1863	if (!mdsc->stopping && inode->i_nlink > 0) {
1864		if (file_wanted) {
1865			retain |= CEPH_CAP_ANY;       /* be greedy */
1866		} else if (S_ISDIR(inode->i_mode) &&
1867			   (issued & CEPH_CAP_FILE_SHARED) &&
1868			    __ceph_dir_is_complete(ci)) {
1869			/*
1870			 * If a directory is complete, we want to keep
1871			 * the exclusive cap. So that MDS does not end up
1872			 * revoking the shared cap on every create/unlink
1873			 * operation.
1874			 */
1875			want = CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
1876			retain |= want;
1877		} else {
1878
1879			retain |= CEPH_CAP_ANY_SHARED;
1880			/*
1881			 * keep RD only if we didn't have the file open RW,
1882			 * because then the mds would revoke it anyway to
1883			 * journal max_size=0.
1884			 */
1885			if (ci->i_max_size == 0)
1886				retain |= CEPH_CAP_ANY_RD;
1887		}
1888	}
1889
1890	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1891	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1892	     ceph_cap_string(file_wanted),
1893	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1894	     ceph_cap_string(ci->i_flushing_caps),
1895	     ceph_cap_string(issued), ceph_cap_string(revoking),
1896	     ceph_cap_string(retain),
1897	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1898	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1899	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1900
1901	/*
1902	 * If we no longer need to hold onto old our caps, and we may
1903	 * have cached pages, but don't want them, then try to invalidate.
1904	 * If we fail, it's because pages are locked.... try again later.
1905	 */
1906	if ((!no_delay || mdsc->stopping) &&
1907	    !S_ISDIR(inode->i_mode) &&		/* ignore readdir cache */
1908	    !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
1909	    inode->i_data.nrpages &&		/* have cached pages */
1910	    (revoking & (CEPH_CAP_FILE_CACHE|
1911			 CEPH_CAP_FILE_LAZYIO)) && /*  or revoking cache */
1912	    !tried_invalidate) {
1913		dout("check_caps trying to invalidate on %p\n", inode);
1914		if (try_nonblocking_invalidate(inode) < 0) {
1915			dout("check_caps queuing invalidate\n");
1916			queue_invalidate = true;
1917			ci->i_rdcache_revoking = ci->i_rdcache_gen;
 
 
 
 
 
 
 
 
 
1918		}
1919		tried_invalidate = true;
1920		goto retry_locked;
1921	}
1922
 
1923	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1924		cap = rb_entry(p, struct ceph_cap, ci_node);
 
1925
1926		/* avoid looping forever */
1927		if (mds >= cap->mds ||
1928		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1929			continue;
1930
1931		/* NOTE: no side-effects allowed, until we take s_mutex */
1932
1933		cap_used = used;
1934		if (ci->i_auth_cap && cap != ci->i_auth_cap)
1935			cap_used &= ~ci->i_auth_cap->issued;
1936
1937		revoking = cap->implemented & ~cap->issued;
1938		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
1939		     cap->mds, cap, ceph_cap_string(cap_used),
1940		     ceph_cap_string(cap->issued),
1941		     ceph_cap_string(cap->implemented),
1942		     ceph_cap_string(revoking));
1943
1944		if (cap == ci->i_auth_cap &&
1945		    (cap->issued & CEPH_CAP_FILE_WR)) {
1946			/* request larger max_size from MDS? */
1947			if (ci->i_wanted_max_size > ci->i_max_size &&
1948			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1949				dout("requesting new max_size\n");
1950				goto ack;
1951			}
1952
1953			/* approaching file_max? */
1954			if (__ceph_should_report_size(ci)) {
 
1955				dout("i_size approaching max_size\n");
1956				goto ack;
1957			}
1958		}
1959		/* flush anything dirty? */
1960		if (cap == ci->i_auth_cap) {
1961			if ((flags & CHECK_CAPS_FLUSH) && ci->i_dirty_caps) {
1962				dout("flushing dirty caps\n");
1963				goto ack;
1964			}
1965			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS) {
1966				dout("flushing snap caps\n");
1967				goto ack;
1968			}
1969		}
1970
1971		/* completed revocation? going down and there are no caps? */
1972		if (revoking && (revoking & cap_used) == 0) {
1973			dout("completed revocation of %s\n",
1974			     ceph_cap_string(cap->implemented & ~cap->issued));
1975			goto ack;
1976		}
1977
1978		/* want more caps from mds? */
1979		if (want & ~(cap->mds_wanted | cap->issued))
1980			goto ack;
1981
1982		/* things we might delay */
1983		if ((cap->issued & ~retain) == 0 &&
1984		    cap->mds_wanted == want)
1985			continue;     /* nope, all good */
1986
1987		if (no_delay)
1988			goto ack;
1989
1990		/* delay? */
1991		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1992		    time_before(jiffies, ci->i_hold_caps_max)) {
1993			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1994			     ceph_cap_string(cap->issued),
1995			     ceph_cap_string(cap->issued & retain),
1996			     ceph_cap_string(cap->mds_wanted),
1997			     ceph_cap_string(want));
1998			delayed++;
1999			continue;
2000		}
2001
2002ack:
2003		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
2004			dout(" skipping %p I_NOFLUSH set\n", inode);
2005			continue;
2006		}
2007
2008		if (session && session != cap->session) {
2009			dout("oops, wrong session %p mutex\n", session);
2010			mutex_unlock(&session->s_mutex);
2011			session = NULL;
2012		}
2013		if (!session) {
2014			session = cap->session;
2015			if (mutex_trylock(&session->s_mutex) == 0) {
2016				dout("inverting session/ino locks on %p\n",
2017				     session);
2018				spin_unlock(&ci->i_ceph_lock);
2019				if (took_snap_rwsem) {
2020					up_read(&mdsc->snap_rwsem);
2021					took_snap_rwsem = 0;
2022				}
2023				mutex_lock(&session->s_mutex);
2024				goto retry;
2025			}
2026		}
2027
2028		/* kick flushing and flush snaps before sending normal
2029		 * cap message */
2030		if (cap == ci->i_auth_cap &&
2031		    (ci->i_ceph_flags &
2032		     (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS))) {
2033			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
2034				__kick_flushing_caps(mdsc, session, ci, 0);
2035				ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2036			}
2037			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2038				__ceph_flush_snaps(ci, session);
2039
2040			goto retry_locked;
2041		}
2042
2043		/* take snap_rwsem after session mutex */
2044		if (!took_snap_rwsem) {
2045			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
2046				dout("inverting snap/in locks on %p\n",
2047				     inode);
2048				spin_unlock(&ci->i_ceph_lock);
2049				down_read(&mdsc->snap_rwsem);
2050				took_snap_rwsem = 1;
2051				goto retry;
2052			}
2053			took_snap_rwsem = 1;
2054		}
2055
2056		if (cap == ci->i_auth_cap && ci->i_dirty_caps) {
2057			flushing = __mark_caps_flushing(inode, session, false,
2058							&flush_tid,
2059							&oldest_flush_tid);
2060		} else {
2061			flushing = 0;
2062			flush_tid = 0;
2063			spin_lock(&mdsc->cap_dirty_lock);
2064			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2065			spin_unlock(&mdsc->cap_dirty_lock);
2066		}
2067
2068		mds = cap->mds;  /* remember mds, so we don't repeat */
2069		sent++;
2070
2071		/* __send_cap drops i_ceph_lock */
2072		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, false,
2073				cap_used, want, retain, flushing,
2074				flush_tid, oldest_flush_tid);
2075		goto retry; /* retake i_ceph_lock and restart our cap scan. */
2076	}
2077
2078	/* Reschedule delayed caps release if we delayed anything */
2079	if (delayed)
 
 
 
 
 
 
 
2080		__cap_delay_requeue(mdsc, ci);
2081
2082	spin_unlock(&ci->i_ceph_lock);
2083
2084	if (queue_invalidate)
2085		ceph_queue_invalidate(inode);
2086
2087	if (session)
2088		mutex_unlock(&session->s_mutex);
2089	if (took_snap_rwsem)
2090		up_read(&mdsc->snap_rwsem);
2091}
2092
2093/*
2094 * Try to flush dirty caps back to the auth mds.
2095 */
2096static int try_flush_caps(struct inode *inode, u64 *ptid)
 
2097{
2098	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2099	struct ceph_inode_info *ci = ceph_inode(inode);
2100	struct ceph_mds_session *session = NULL;
2101	int flushing = 0;
2102	u64 flush_tid = 0, oldest_flush_tid = 0;
2103
2104retry:
2105	spin_lock(&ci->i_ceph_lock);
2106	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
2107		spin_unlock(&ci->i_ceph_lock);
2108		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
2109		goto out;
2110	}
2111	if (ci->i_dirty_caps && ci->i_auth_cap) {
2112		struct ceph_cap *cap = ci->i_auth_cap;
2113		int used = __ceph_caps_used(ci);
2114		int want = __ceph_caps_wanted(ci);
2115		int delayed;
2116
2117		if (!session || session != cap->session) {
2118			spin_unlock(&ci->i_ceph_lock);
2119			if (session)
2120				mutex_unlock(&session->s_mutex);
2121			session = cap->session;
2122			mutex_lock(&session->s_mutex);
2123			goto retry;
2124		}
2125		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {
2126			spin_unlock(&ci->i_ceph_lock);
2127			goto out;
2128		}
2129
2130		flushing = __mark_caps_flushing(inode, session, true,
2131						&flush_tid, &oldest_flush_tid);
2132
2133		/* __send_cap drops i_ceph_lock */
2134		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, true,
2135				used, want, (cap->issued | cap->implemented),
2136				flushing, flush_tid, oldest_flush_tid);
 
 
2137
2138		if (delayed) {
2139			spin_lock(&ci->i_ceph_lock);
2140			__cap_delay_requeue(mdsc, ci);
2141			spin_unlock(&ci->i_ceph_lock);
2142		}
2143	} else {
2144		if (!list_empty(&ci->i_cap_flush_list)) {
2145			struct ceph_cap_flush *cf =
2146				list_last_entry(&ci->i_cap_flush_list,
2147						struct ceph_cap_flush, i_list);
2148			cf->wake = true;
2149			flush_tid = cf->tid;
2150		}
2151		flushing = ci->i_flushing_caps;
2152		spin_unlock(&ci->i_ceph_lock);
2153	}
2154out:
2155	if (session)
 
 
2156		mutex_unlock(&session->s_mutex);
2157
2158	*ptid = flush_tid;
2159	return flushing;
2160}
2161
2162/*
2163 * Return true if we've flushed caps through the given flush_tid.
2164 */
2165static int caps_are_flushed(struct inode *inode, u64 flush_tid)
2166{
2167	struct ceph_inode_info *ci = ceph_inode(inode);
2168	int ret = 1;
2169
2170	spin_lock(&ci->i_ceph_lock);
2171	if (!list_empty(&ci->i_cap_flush_list)) {
2172		struct ceph_cap_flush * cf =
2173			list_first_entry(&ci->i_cap_flush_list,
2174					 struct ceph_cap_flush, i_list);
2175		if (cf->tid <= flush_tid)
2176			ret = 0;
2177	}
 
2178	spin_unlock(&ci->i_ceph_lock);
2179	return ret;
2180}
2181
2182/*
2183 * wait for any unsafe requests to complete.
 
 
 
2184 */
2185static int unsafe_request_wait(struct inode *inode)
2186{
2187	struct ceph_inode_info *ci = ceph_inode(inode);
2188	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
2189	int ret, err = 0;
 
2190
2191	spin_lock(&ci->i_unsafe_lock);
2192	if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) {
2193		req1 = list_last_entry(&ci->i_unsafe_dirops,
2194					struct ceph_mds_request,
2195					r_unsafe_dir_item);
2196		ceph_mdsc_get_request(req1);
2197	}
2198	if (!list_empty(&ci->i_unsafe_iops)) {
2199		req2 = list_last_entry(&ci->i_unsafe_iops,
2200					struct ceph_mds_request,
2201					r_unsafe_target_item);
2202		ceph_mdsc_get_request(req2);
2203	}
2204	spin_unlock(&ci->i_unsafe_lock);
2205
2206	dout("unsafe_request_wait %p wait on tid %llu %llu\n",
2207	     inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL);
2208	if (req1) {
2209		ret = !wait_for_completion_timeout(&req1->r_safe_completion,
2210					ceph_timeout_jiffies(req1->r_timeout));
2211		if (ret)
2212			err = -EIO;
2213		ceph_mdsc_put_request(req1);
2214	}
2215	if (req2) {
2216		ret = !wait_for_completion_timeout(&req2->r_safe_completion,
2217					ceph_timeout_jiffies(req2->r_timeout));
2218		if (ret)
2219			err = -EIO;
2220		ceph_mdsc_put_request(req2);
2221	}
2222	return err;
 
 
 
 
 
 
 
 
2223}
2224
2225int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2226{
2227	struct inode *inode = file->f_mapping->host;
2228	struct ceph_inode_info *ci = ceph_inode(inode);
2229	u64 flush_tid;
2230	int ret;
2231	int dirty;
2232
2233	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
 
2234
2235	ret = file_write_and_wait_range(file, start, end);
2236	if (ret < 0)
2237		goto out;
2238
2239	if (datasync)
2240		goto out;
2241
2242	inode_lock(inode);
2243
2244	dirty = try_flush_caps(inode, &flush_tid);
2245	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
2246
2247	ret = unsafe_request_wait(inode);
2248
2249	/*
2250	 * only wait on non-file metadata writeback (the mds
2251	 * can recover size and mtime, so we don't need to
2252	 * wait for that)
2253	 */
2254	if (!ret && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
 
2255		ret = wait_event_interruptible(ci->i_cap_wq,
2256					caps_are_flushed(inode, flush_tid));
2257	}
2258	inode_unlock(inode);
2259out:
2260	dout("fsync %p%s result=%d\n", inode, datasync ? " datasync" : "", ret);
2261	return ret;
2262}
2263
2264/*
2265 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
2266 * queue inode for flush but don't do so immediately, because we can
2267 * get by with fewer MDS messages if we wait for data writeback to
2268 * complete first.
2269 */
2270int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
2271{
2272	struct ceph_inode_info *ci = ceph_inode(inode);
2273	u64 flush_tid;
2274	int err = 0;
2275	int dirty;
2276	int wait = (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync);
2277
2278	dout("write_inode %p wait=%d\n", inode, wait);
2279	if (wait) {
2280		dirty = try_flush_caps(inode, &flush_tid);
2281		if (dirty)
2282			err = wait_event_interruptible(ci->i_cap_wq,
2283				       caps_are_flushed(inode, flush_tid));
2284	} else {
2285		struct ceph_mds_client *mdsc =
2286			ceph_sb_to_client(inode->i_sb)->mdsc;
2287
2288		spin_lock(&ci->i_ceph_lock);
2289		if (__ceph_caps_dirty(ci))
2290			__cap_delay_requeue_front(mdsc, ci);
2291		spin_unlock(&ci->i_ceph_lock);
2292	}
2293	return err;
2294}
2295
2296static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
2297				 struct ceph_mds_session *session,
2298				 struct ceph_inode_info *ci,
2299				 u64 oldest_flush_tid)
2300	__releases(ci->i_ceph_lock)
2301	__acquires(ci->i_ceph_lock)
2302{
2303	struct inode *inode = &ci->vfs_inode;
2304	struct ceph_cap *cap;
2305	struct ceph_cap_flush *cf;
2306	int ret;
2307	u64 first_tid = 0;
2308
2309	list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
2310		if (cf->tid < first_tid)
2311			continue;
2312
2313		cap = ci->i_auth_cap;
2314		if (!(cap && cap->session == session)) {
2315			pr_err("%p auth cap %p not mds%d ???\n",
2316			       inode, cap, session->s_mds);
2317			break;
2318		}
2319
2320		first_tid = cf->tid + 1;
2321
2322		if (cf->caps) {
2323			dout("kick_flushing_caps %p cap %p tid %llu %s\n",
2324			     inode, cap, cf->tid, ceph_cap_string(cf->caps));
2325			ci->i_ceph_flags |= CEPH_I_NODELAY;
2326			ret = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2327					  false, __ceph_caps_used(ci),
2328					  __ceph_caps_wanted(ci),
2329					  cap->issued | cap->implemented,
2330					  cf->caps, cf->tid, oldest_flush_tid);
2331			if (ret) {
2332				pr_err("kick_flushing_caps: error sending "
2333					"cap flush, ino (%llx.%llx) "
2334					"tid %llu flushing %s\n",
2335					ceph_vinop(inode), cf->tid,
2336					ceph_cap_string(cf->caps));
2337			}
2338		} else {
2339			struct ceph_cap_snap *capsnap =
2340					container_of(cf, struct ceph_cap_snap,
2341						    cap_flush);
2342			dout("kick_flushing_caps %p capsnap %p tid %llu %s\n",
2343			     inode, capsnap, cf->tid,
2344			     ceph_cap_string(capsnap->dirty));
2345
2346			refcount_inc(&capsnap->nref);
2347			spin_unlock(&ci->i_ceph_lock);
2348
2349			ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
2350						oldest_flush_tid);
2351			if (ret < 0) {
2352				pr_err("kick_flushing_caps: error sending "
2353					"cap flushsnap, ino (%llx.%llx) "
2354					"tid %llu follows %llu\n",
2355					ceph_vinop(inode), cf->tid,
2356					capsnap->follows);
2357			}
2358
2359			ceph_put_cap_snap(capsnap);
2360		}
2361
2362		spin_lock(&ci->i_ceph_lock);
2363	}
2364}
2365
2366void ceph_early_kick_flushing_caps(struct ceph_mds_client *mdsc,
2367				   struct ceph_mds_session *session)
2368{
2369	struct ceph_inode_info *ci;
2370	struct ceph_cap *cap;
2371	u64 oldest_flush_tid;
2372
2373	dout("early_kick_flushing_caps mds%d\n", session->s_mds);
2374
2375	spin_lock(&mdsc->cap_dirty_lock);
2376	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2377	spin_unlock(&mdsc->cap_dirty_lock);
 
 
 
2378
2379	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2380		spin_lock(&ci->i_ceph_lock);
2381		cap = ci->i_auth_cap;
2382		if (!(cap && cap->session == session)) {
2383			pr_err("%p auth cap %p not mds%d ???\n",
2384				&ci->vfs_inode, cap, session->s_mds);
2385			spin_unlock(&ci->i_ceph_lock);
2386			continue;
2387		}
2388
2389
2390		/*
2391		 * if flushing caps were revoked, we re-send the cap flush
2392		 * in client reconnect stage. This guarantees MDS * processes
2393		 * the cap flush message before issuing the flushing caps to
2394		 * other client.
2395		 */
2396		if ((cap->issued & ci->i_flushing_caps) !=
2397		    ci->i_flushing_caps) {
2398			ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2399			__kick_flushing_caps(mdsc, session, ci,
2400					     oldest_flush_tid);
2401		} else {
2402			ci->i_ceph_flags |= CEPH_I_KICK_FLUSH;
 
2403		}
2404
2405		spin_unlock(&ci->i_ceph_lock);
2406	}
2407}
2408
2409void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
2410			     struct ceph_mds_session *session)
2411{
2412	struct ceph_inode_info *ci;
2413	struct ceph_cap *cap;
2414	u64 oldest_flush_tid;
2415
2416	dout("kick_flushing_caps mds%d\n", session->s_mds);
2417
2418	spin_lock(&mdsc->cap_dirty_lock);
2419	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2420	spin_unlock(&mdsc->cap_dirty_lock);
2421
 
2422	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
 
 
 
 
2423		spin_lock(&ci->i_ceph_lock);
2424		cap = ci->i_auth_cap;
2425		if (!(cap && cap->session == session)) {
2426			pr_err("%p auth cap %p not mds%d ???\n",
2427				&ci->vfs_inode, cap, session->s_mds);
 
 
 
 
 
 
 
 
 
 
 
 
 
2428			spin_unlock(&ci->i_ceph_lock);
2429			continue;
2430		}
2431		if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
2432			ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2433			__kick_flushing_caps(mdsc, session, ci,
2434					     oldest_flush_tid);
2435		}
2436		spin_unlock(&ci->i_ceph_lock);
2437	}
2438}
2439
2440static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
2441				     struct ceph_mds_session *session,
2442				     struct inode *inode)
2443	__releases(ci->i_ceph_lock)
2444{
2445	struct ceph_inode_info *ci = ceph_inode(inode);
2446	struct ceph_cap *cap;
 
2447
 
2448	cap = ci->i_auth_cap;
2449	dout("kick_flushing_inode_caps %p flushing %s\n", inode,
2450	     ceph_cap_string(ci->i_flushing_caps));
2451
2452	if (!list_empty(&ci->i_cap_flush_list)) {
2453		u64 oldest_flush_tid;
2454		spin_lock(&mdsc->cap_dirty_lock);
2455		list_move_tail(&ci->i_flushing_item,
2456			       &cap->session->s_cap_flushing);
2457		oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2458		spin_unlock(&mdsc->cap_dirty_lock);
2459
2460		ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2461		__kick_flushing_caps(mdsc, session, ci, oldest_flush_tid);
2462		spin_unlock(&ci->i_ceph_lock);
2463	} else {
2464		spin_unlock(&ci->i_ceph_lock);
2465	}
2466}
2467
2468
2469/*
2470 * Take references to capabilities we hold, so that we don't release
2471 * them to the MDS prematurely.
2472 *
2473 * Protected by i_ceph_lock.
2474 */
2475static void __take_cap_refs(struct ceph_inode_info *ci, int got,
2476			    bool snap_rwsem_locked)
2477{
2478	if (got & CEPH_CAP_PIN)
2479		ci->i_pin_ref++;
2480	if (got & CEPH_CAP_FILE_RD)
2481		ci->i_rd_ref++;
2482	if (got & CEPH_CAP_FILE_CACHE)
2483		ci->i_rdcache_ref++;
2484	if (got & CEPH_CAP_FILE_WR) {
2485		if (ci->i_wr_ref == 0 && !ci->i_head_snapc) {
2486			BUG_ON(!snap_rwsem_locked);
2487			ci->i_head_snapc = ceph_get_snap_context(
2488					ci->i_snap_realm->cached_context);
2489		}
2490		ci->i_wr_ref++;
2491	}
2492	if (got & CEPH_CAP_FILE_BUFFER) {
2493		if (ci->i_wb_ref == 0)
2494			ihold(&ci->vfs_inode);
2495		ci->i_wb_ref++;
2496		dout("__take_cap_refs %p wb %d -> %d (?)\n",
2497		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2498	}
2499}
2500
2501/*
2502 * Try to grab cap references.  Specify those refs we @want, and the
2503 * minimal set we @need.  Also include the larger offset we are writing
2504 * to (when applicable), and check against max_size here as well.
2505 * Note that caller is responsible for ensuring max_size increases are
2506 * requested from the MDS.
2507 */
2508static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
2509			    loff_t endoff, bool nonblock, int *got, int *err)
2510{
2511	struct inode *inode = &ci->vfs_inode;
2512	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2513	int ret = 0;
2514	int have, implemented;
2515	int file_wanted;
2516	bool snap_rwsem_locked = false;
2517
2518	dout("get_cap_refs %p need %s want %s\n", inode,
2519	     ceph_cap_string(need), ceph_cap_string(want));
2520
2521again:
2522	spin_lock(&ci->i_ceph_lock);
2523
2524	/* make sure file is actually open */
2525	file_wanted = __ceph_caps_file_wanted(ci);
2526	if ((file_wanted & need) != need) {
2527		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2528		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2529		*err = -EBADF;
2530		ret = 1;
2531		goto out_unlock;
2532	}
2533
2534	/* finish pending truncate */
2535	while (ci->i_truncate_pending) {
2536		spin_unlock(&ci->i_ceph_lock);
2537		if (snap_rwsem_locked) {
2538			up_read(&mdsc->snap_rwsem);
2539			snap_rwsem_locked = false;
2540		}
2541		__ceph_do_pending_vmtruncate(inode);
2542		spin_lock(&ci->i_ceph_lock);
2543	}
2544
2545	have = __ceph_caps_issued(ci, &implemented);
2546
2547	if (have & need & CEPH_CAP_FILE_WR) {
2548		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2549			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2550			     inode, endoff, ci->i_max_size);
2551			if (endoff > ci->i_requested_max_size) {
2552				*err = -EAGAIN;
2553				ret = 1;
2554			}
2555			goto out_unlock;
2556		}
2557		/*
2558		 * If a sync write is in progress, we must wait, so that we
2559		 * can get a final snapshot value for size+mtime.
2560		 */
2561		if (__ceph_have_pending_cap_snap(ci)) {
2562			dout("get_cap_refs %p cap_snap_pending\n", inode);
2563			goto out_unlock;
2564		}
2565	}
 
 
 
 
 
 
 
2566
2567	if ((have & need) == need) {
2568		/*
2569		 * Look at (implemented & ~have & not) so that we keep waiting
2570		 * on transition from wanted -> needed caps.  This is needed
2571		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2572		 * going before a prior buffered writeback happens.
2573		 */
2574		int not = want & ~(have & need);
2575		int revoking = implemented & ~have;
2576		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2577		     inode, ceph_cap_string(have), ceph_cap_string(not),
2578		     ceph_cap_string(revoking));
2579		if ((revoking & not) == 0) {
2580			if (!snap_rwsem_locked &&
2581			    !ci->i_head_snapc &&
2582			    (need & CEPH_CAP_FILE_WR)) {
2583				if (!down_read_trylock(&mdsc->snap_rwsem)) {
2584					/*
2585					 * we can not call down_read() when
2586					 * task isn't in TASK_RUNNING state
2587					 */
2588					if (nonblock) {
2589						*err = -EAGAIN;
2590						ret = 1;
2591						goto out_unlock;
2592					}
2593
2594					spin_unlock(&ci->i_ceph_lock);
2595					down_read(&mdsc->snap_rwsem);
2596					snap_rwsem_locked = true;
2597					goto again;
2598				}
2599				snap_rwsem_locked = true;
2600			}
2601			*got = need | (have & want);
2602			if ((need & CEPH_CAP_FILE_RD) &&
2603			    !(*got & CEPH_CAP_FILE_CACHE))
2604				ceph_disable_fscache_readpage(ci);
2605			__take_cap_refs(ci, *got, true);
2606			ret = 1;
2607		}
2608	} else {
2609		int session_readonly = false;
2610		if ((need & CEPH_CAP_FILE_WR) && ci->i_auth_cap) {
2611			struct ceph_mds_session *s = ci->i_auth_cap->session;
2612			spin_lock(&s->s_cap_lock);
2613			session_readonly = s->s_readonly;
2614			spin_unlock(&s->s_cap_lock);
2615		}
2616		if (session_readonly) {
2617			dout("get_cap_refs %p needed %s but mds%d readonly\n",
2618			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
2619			*err = -EROFS;
2620			ret = 1;
2621			goto out_unlock;
2622		}
2623
2624		if (ci->i_ceph_flags & CEPH_I_CAP_DROPPED) {
2625			int mds_wanted;
2626			if (READ_ONCE(mdsc->fsc->mount_state) ==
2627			    CEPH_MOUNT_SHUTDOWN) {
2628				dout("get_cap_refs %p forced umount\n", inode);
2629				*err = -EIO;
2630				ret = 1;
2631				goto out_unlock;
2632			}
2633			mds_wanted = __ceph_caps_mds_wanted(ci, false);
2634			if (need & ~(mds_wanted & need)) {
2635				dout("get_cap_refs %p caps were dropped"
2636				     " (session killed?)\n", inode);
2637				*err = -ESTALE;
2638				ret = 1;
2639				goto out_unlock;
2640			}
2641			if (!(file_wanted & ~mds_wanted))
2642				ci->i_ceph_flags &= ~CEPH_I_CAP_DROPPED;
2643		}
2644
2645		dout("get_cap_refs %p have %s needed %s\n", inode,
2646		     ceph_cap_string(have), ceph_cap_string(need));
2647	}
2648out_unlock:
2649	spin_unlock(&ci->i_ceph_lock);
2650	if (snap_rwsem_locked)
2651		up_read(&mdsc->snap_rwsem);
2652
2653	dout("get_cap_refs %p ret %d got %s\n", inode,
2654	     ret, ceph_cap_string(*got));
2655	return ret;
2656}
2657
2658/*
2659 * Check the offset we are writing up to against our current
2660 * max_size.  If necessary, tell the MDS we want to write to
2661 * a larger offset.
2662 */
2663static void check_max_size(struct inode *inode, loff_t endoff)
2664{
2665	struct ceph_inode_info *ci = ceph_inode(inode);
2666	int check = 0;
2667
2668	/* do we need to explicitly request a larger max_size? */
2669	spin_lock(&ci->i_ceph_lock);
2670	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
 
 
2671		dout("write %p at large endoff %llu, req max_size\n",
2672		     inode, endoff);
2673		ci->i_wanted_max_size = endoff;
2674	}
2675	/* duplicate ceph_check_caps()'s logic */
2676	if (ci->i_auth_cap &&
2677	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2678	    ci->i_wanted_max_size > ci->i_max_size &&
2679	    ci->i_wanted_max_size > ci->i_requested_max_size)
2680		check = 1;
 
2681	spin_unlock(&ci->i_ceph_lock);
2682	if (check)
2683		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2684}
2685
2686int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, int *got)
2687{
2688	int ret, err = 0;
2689
2690	BUG_ON(need & ~CEPH_CAP_FILE_RD);
2691	BUG_ON(want & ~(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
2692	ret = ceph_pool_perm_check(ci, need);
2693	if (ret < 0)
2694		return ret;
2695
2696	ret = try_get_cap_refs(ci, need, want, 0, true, got, &err);
2697	if (ret) {
2698		if (err == -EAGAIN) {
2699			ret = 0;
2700		} else if (err < 0) {
2701			ret = err;
2702		}
2703	}
2704	return ret;
2705}
2706
2707/*
2708 * Wait for caps, and take cap references.  If we can't get a WR cap
2709 * due to a small max_size, make sure we check_max_size (and possibly
2710 * ask the mds) so we don't get hung up indefinitely.
2711 */
2712int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
2713		  loff_t endoff, int *got, struct page **pinned_page)
2714{
2715	int _got, ret, err = 0;
2716
2717	ret = ceph_pool_perm_check(ci, need);
2718	if (ret < 0)
2719		return ret;
2720
2721	while (true) {
2722		if (endoff > 0)
2723			check_max_size(&ci->vfs_inode, endoff);
2724
2725		err = 0;
2726		_got = 0;
2727		ret = try_get_cap_refs(ci, need, want, endoff,
2728				       false, &_got, &err);
2729		if (ret) {
2730			if (err == -EAGAIN)
2731				continue;
2732			if (err < 0)
2733				ret = err;
2734		} else {
2735			DEFINE_WAIT_FUNC(wait, woken_wake_function);
2736			add_wait_queue(&ci->i_cap_wq, &wait);
2737
2738			while (!try_get_cap_refs(ci, need, want, endoff,
2739						 true, &_got, &err)) {
2740				if (signal_pending(current)) {
2741					ret = -ERESTARTSYS;
2742					break;
2743				}
2744				wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2745			}
2746
2747			remove_wait_queue(&ci->i_cap_wq, &wait);
2748
2749			if (err == -EAGAIN)
2750				continue;
2751			if (err < 0)
2752				ret = err;
2753		}
2754		if (ret < 0) {
2755			if (err == -ESTALE) {
2756				/* session was killed, try renew caps */
2757				ret = ceph_renew_caps(&ci->vfs_inode);
2758				if (ret == 0)
2759					continue;
2760			}
2761			return ret;
2762		}
2763
2764		if (ci->i_inline_version != CEPH_INLINE_NONE &&
2765		    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
2766		    i_size_read(&ci->vfs_inode) > 0) {
2767			struct page *page =
2768				find_get_page(ci->vfs_inode.i_mapping, 0);
2769			if (page) {
2770				if (PageUptodate(page)) {
2771					*pinned_page = page;
2772					break;
2773				}
2774				put_page(page);
2775			}
2776			/*
2777			 * drop cap refs first because getattr while
2778			 * holding * caps refs can cause deadlock.
2779			 */
2780			ceph_put_cap_refs(ci, _got);
2781			_got = 0;
2782
2783			/*
2784			 * getattr request will bring inline data into
2785			 * page cache
2786			 */
2787			ret = __ceph_do_getattr(&ci->vfs_inode, NULL,
2788						CEPH_STAT_CAP_INLINE_DATA,
2789						true);
2790			if (ret < 0)
2791				return ret;
2792			continue;
2793		}
2794		break;
2795	}
2796
2797	if ((_got & CEPH_CAP_FILE_RD) && (_got & CEPH_CAP_FILE_CACHE))
2798		ceph_fscache_revalidate_cookie(ci);
2799
2800	*got = _got;
2801	return 0;
2802}
2803
2804/*
2805 * Take cap refs.  Caller must already know we hold at least one ref
2806 * on the caps in question or we don't know this is safe.
2807 */
2808void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2809{
2810	spin_lock(&ci->i_ceph_lock);
2811	__take_cap_refs(ci, caps, false);
2812	spin_unlock(&ci->i_ceph_lock);
2813}
2814
2815
2816/*
2817 * drop cap_snap that is not associated with any snapshot.
2818 * we don't need to send FLUSHSNAP message for it.
2819 */
2820static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
2821				  struct ceph_cap_snap *capsnap)
2822{
2823	if (!capsnap->need_flush &&
2824	    !capsnap->writing && !capsnap->dirty_pages) {
2825		dout("dropping cap_snap %p follows %llu\n",
2826		     capsnap, capsnap->follows);
2827		BUG_ON(capsnap->cap_flush.tid > 0);
2828		ceph_put_snap_context(capsnap->context);
2829		if (!list_is_last(&capsnap->ci_item, &ci->i_cap_snaps))
2830			ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
2831
2832		list_del(&capsnap->ci_item);
2833		ceph_put_cap_snap(capsnap);
2834		return 1;
2835	}
2836	return 0;
2837}
2838
2839/*
2840 * Release cap refs.
2841 *
2842 * If we released the last ref on any given cap, call ceph_check_caps
2843 * to release (or schedule a release).
2844 *
2845 * If we are releasing a WR cap (from a sync write), finalize any affected
2846 * cap_snap, and wake up any waiters.
2847 */
2848void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2849{
2850	struct inode *inode = &ci->vfs_inode;
2851	int last = 0, put = 0, flushsnaps = 0, wake = 0;
 
2852
2853	spin_lock(&ci->i_ceph_lock);
2854	if (had & CEPH_CAP_PIN)
2855		--ci->i_pin_ref;
2856	if (had & CEPH_CAP_FILE_RD)
2857		if (--ci->i_rd_ref == 0)
2858			last++;
2859	if (had & CEPH_CAP_FILE_CACHE)
2860		if (--ci->i_rdcache_ref == 0)
2861			last++;
2862	if (had & CEPH_CAP_FILE_BUFFER) {
2863		if (--ci->i_wb_ref == 0) {
2864			last++;
2865			put++;
2866		}
2867		dout("put_cap_refs %p wb %d -> %d (?)\n",
2868		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2869	}
2870	if (had & CEPH_CAP_FILE_WR)
2871		if (--ci->i_wr_ref == 0) {
2872			last++;
2873			if (__ceph_have_pending_cap_snap(ci)) {
2874				struct ceph_cap_snap *capsnap =
2875					list_last_entry(&ci->i_cap_snaps,
2876							struct ceph_cap_snap,
2877							ci_item);
2878				capsnap->writing = 0;
2879				if (ceph_try_drop_cap_snap(ci, capsnap))
2880					put++;
2881				else if (__ceph_finish_cap_snap(ci, capsnap))
2882					flushsnaps = 1;
2883				wake = 1;
2884			}
2885			if (ci->i_wrbuffer_ref_head == 0 &&
2886			    ci->i_dirty_caps == 0 &&
2887			    ci->i_flushing_caps == 0) {
2888				BUG_ON(!ci->i_head_snapc);
2889				ceph_put_snap_context(ci->i_head_snapc);
2890				ci->i_head_snapc = NULL;
2891			}
2892			/* see comment in __ceph_remove_cap() */
2893			if (!__ceph_is_any_caps(ci) && ci->i_snap_realm)
2894				drop_inode_snap_realm(ci);
2895		}
2896	spin_unlock(&ci->i_ceph_lock);
2897
2898	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2899	     last ? " last" : "", put ? " put" : "");
2900
2901	if (last && !flushsnaps)
2902		ceph_check_caps(ci, 0, NULL);
2903	else if (flushsnaps)
2904		ceph_flush_snaps(ci, NULL);
2905	if (wake)
2906		wake_up_all(&ci->i_cap_wq);
2907	while (put-- > 0)
2908		iput(inode);
2909}
2910
2911/*
2912 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2913 * context.  Adjust per-snap dirty page accounting as appropriate.
2914 * Once all dirty data for a cap_snap is flushed, flush snapped file
2915 * metadata back to the MDS.  If we dropped the last ref, call
2916 * ceph_check_caps.
2917 */
2918void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2919				struct ceph_snap_context *snapc)
2920{
2921	struct inode *inode = &ci->vfs_inode;
 
 
 
 
2922	struct ceph_cap_snap *capsnap = NULL;
2923	int put = 0;
2924	bool last = false;
2925	bool found = false;
2926	bool flush_snaps = false;
2927	bool complete_capsnap = false;
2928
2929	spin_lock(&ci->i_ceph_lock);
2930	ci->i_wrbuffer_ref -= nr;
2931	if (ci->i_wrbuffer_ref == 0) {
2932		last = true;
2933		put++;
2934	}
2935
2936	if (ci->i_head_snapc == snapc) {
2937		ci->i_wrbuffer_ref_head -= nr;
2938		if (ci->i_wrbuffer_ref_head == 0 &&
2939		    ci->i_wr_ref == 0 &&
2940		    ci->i_dirty_caps == 0 &&
2941		    ci->i_flushing_caps == 0) {
2942			BUG_ON(!ci->i_head_snapc);
2943			ceph_put_snap_context(ci->i_head_snapc);
2944			ci->i_head_snapc = NULL;
2945		}
2946		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2947		     inode,
2948		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2949		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2950		     last ? " LAST" : "");
2951	} else {
2952		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2953			if (capsnap->context == snapc) {
2954				found = true;
2955				break;
2956			}
2957		}
2958		BUG_ON(!found);
2959		capsnap->dirty_pages -= nr;
2960		if (capsnap->dirty_pages == 0) {
2961			complete_capsnap = true;
2962			if (!capsnap->writing) {
2963				if (ceph_try_drop_cap_snap(ci, capsnap)) {
2964					put++;
2965				} else {
2966					ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
2967					flush_snaps = true;
2968				}
2969			}
2970		}
2971		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2972		     " snap %lld %d/%d -> %d/%d %s%s\n",
2973		     inode, capsnap, capsnap->context->seq,
2974		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2975		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2976		     last ? " (wrbuffer last)" : "",
2977		     complete_capsnap ? " (complete capsnap)" : "");
 
 
 
 
 
 
 
2978	}
2979
2980	spin_unlock(&ci->i_ceph_lock);
2981
2982	if (last) {
2983		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2984	} else if (flush_snaps) {
2985		ceph_flush_snaps(ci, NULL);
2986	}
2987	if (complete_capsnap)
2988		wake_up_all(&ci->i_cap_wq);
2989	while (put-- > 0)
2990		iput(inode);
2991}
2992
2993/*
2994 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
2995 */
2996static void invalidate_aliases(struct inode *inode)
2997{
2998	struct dentry *dn, *prev = NULL;
2999
3000	dout("invalidate_aliases inode %p\n", inode);
3001	d_prune_aliases(inode);
3002	/*
3003	 * For non-directory inode, d_find_alias() only returns
3004	 * hashed dentry. After calling d_invalidate(), the
3005	 * dentry becomes unhashed.
3006	 *
3007	 * For directory inode, d_find_alias() can return
3008	 * unhashed dentry. But directory inode should have
3009	 * one alias at most.
3010	 */
3011	while ((dn = d_find_alias(inode))) {
3012		if (dn == prev) {
3013			dput(dn);
3014			break;
3015		}
3016		d_invalidate(dn);
3017		if (prev)
3018			dput(prev);
3019		prev = dn;
3020	}
3021	if (prev)
3022		dput(prev);
3023}
3024
3025/*
3026 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
3027 * actually be a revocation if it specifies a smaller cap set.)
3028 *
3029 * caller holds s_mutex and i_ceph_lock, we drop both.
 
 
 
 
 
3030 */
3031static void handle_cap_grant(struct ceph_mds_client *mdsc,
3032			     struct inode *inode, struct ceph_mds_caps *grant,
3033			     struct ceph_string **pns, u64 inline_version,
3034			     void *inline_data, u32 inline_len,
3035			     struct ceph_buffer *xattr_buf,
3036			     struct ceph_mds_session *session,
3037			     struct ceph_cap *cap, int issued)
3038	__releases(ci->i_ceph_lock)
3039	__releases(mdsc->snap_rwsem)
3040{
3041	struct ceph_inode_info *ci = ceph_inode(inode);
3042	int mds = session->s_mds;
3043	int seq = le32_to_cpu(grant->seq);
3044	int newcaps = le32_to_cpu(grant->caps);
3045	int used, wanted, dirty;
3046	u64 size = le64_to_cpu(grant->size);
3047	u64 max_size = le64_to_cpu(grant->max_size);
3048	struct timespec mtime, atime, ctime;
3049	int check_caps = 0;
3050	bool wake = false;
3051	bool writeback = false;
3052	bool queue_trunc = false;
3053	bool queue_invalidate = false;
3054	bool deleted_inode = false;
3055	bool fill_inline = false;
3056
3057	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
3058	     inode, cap, mds, seq, ceph_cap_string(newcaps));
3059	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
3060		inode->i_size);
3061
3062
3063	/*
3064	 * auth mds of the inode changed. we received the cap export message,
3065	 * but still haven't received the cap import message. handle_cap_export
3066	 * updated the new auth MDS' cap.
3067	 *
3068	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
3069	 * that was sent before the cap import message. So don't remove caps.
3070	 */
3071	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
3072		WARN_ON(cap != ci->i_auth_cap);
3073		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
3074		seq = cap->seq;
3075		newcaps |= cap->issued;
3076	}
3077
3078	/*
3079	 * If CACHE is being revoked, and we have no dirty buffers,
3080	 * try to invalidate (once).  (If there are dirty buffers, we
3081	 * will invalidate _after_ writeback.)
3082	 */
3083	if (!S_ISDIR(inode->i_mode) && /* don't invalidate readdir cache */
3084	    ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
3085	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3086	    !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
3087		if (try_nonblocking_invalidate(inode)) {
 
 
3088			/* there were locked pages.. invalidate later
3089			   in a separate thread. */
3090			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
3091				queue_invalidate = true;
3092				ci->i_rdcache_revoking = ci->i_rdcache_gen;
3093			}
3094		}
3095	}
3096
3097	/* side effects now are allowed */
 
 
 
 
3098	cap->cap_gen = session->s_cap_gen;
3099	cap->seq = seq;
3100
3101	__check_cap_issue(ci, cap, newcaps);
3102
3103	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
3104	    (issued & CEPH_CAP_AUTH_EXCL) == 0) {
3105		inode->i_mode = le32_to_cpu(grant->mode);
3106		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
3107		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
3108		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
3109		     from_kuid(&init_user_ns, inode->i_uid),
3110		     from_kgid(&init_user_ns, inode->i_gid));
3111	}
3112
3113	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
3114	    (issued & CEPH_CAP_LINK_EXCL) == 0) {
3115		set_nlink(inode, le32_to_cpu(grant->nlink));
3116		if (inode->i_nlink == 0 &&
3117		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
3118			deleted_inode = true;
3119	}
3120
3121	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
3122		int len = le32_to_cpu(grant->xattr_len);
3123		u64 version = le64_to_cpu(grant->xattr_version);
3124
3125		if (version > ci->i_xattrs.version) {
3126			dout(" got new xattrs v%llu on %p len %d\n",
3127			     version, inode, len);
3128			if (ci->i_xattrs.blob)
3129				ceph_buffer_put(ci->i_xattrs.blob);
3130			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
3131			ci->i_xattrs.version = version;
3132			ceph_forget_all_cached_acls(inode);
3133		}
3134	}
3135
3136	if (newcaps & CEPH_CAP_ANY_RD) {
3137		/* ctime/mtime/atime? */
3138		ceph_decode_timespec(&mtime, &grant->mtime);
3139		ceph_decode_timespec(&atime, &grant->atime);
3140		ceph_decode_timespec(&ctime, &grant->ctime);
3141		ceph_fill_file_time(inode, issued,
3142				    le32_to_cpu(grant->time_warp_seq),
3143				    &ctime, &mtime, &atime);
3144	}
3145
3146	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
3147		/* file layout may have changed */
3148		s64 old_pool = ci->i_layout.pool_id;
3149		struct ceph_string *old_ns;
3150
3151		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
3152		old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
3153					lockdep_is_held(&ci->i_ceph_lock));
3154		rcu_assign_pointer(ci->i_layout.pool_ns, *pns);
3155
3156		if (ci->i_layout.pool_id != old_pool || *pns != old_ns)
3157			ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
3158
3159		*pns = old_ns;
3160
3161		/* size/truncate_seq? */
3162		queue_trunc = ceph_fill_file_size(inode, issued,
3163					le32_to_cpu(grant->truncate_seq),
3164					le64_to_cpu(grant->truncate_size),
3165					size);
3166	}
3167
3168	if (ci->i_auth_cap == cap && (newcaps & CEPH_CAP_ANY_FILE_WR)) {
3169		if (max_size != ci->i_max_size) {
3170			dout("max_size %lld -> %llu\n",
3171			     ci->i_max_size, max_size);
3172			ci->i_max_size = max_size;
3173			if (max_size >= ci->i_wanted_max_size) {
3174				ci->i_wanted_max_size = 0;  /* reset */
3175				ci->i_requested_max_size = 0;
3176			}
3177			wake = true;
3178		} else if (ci->i_wanted_max_size > ci->i_max_size &&
3179			   ci->i_wanted_max_size > ci->i_requested_max_size) {
3180			/* CEPH_CAP_OP_IMPORT */
3181			wake = true;
3182		}
 
3183	}
3184
3185	/* check cap bits */
3186	wanted = __ceph_caps_wanted(ci);
3187	used = __ceph_caps_used(ci);
3188	dirty = __ceph_caps_dirty(ci);
3189	dout(" my wanted = %s, used = %s, dirty %s\n",
3190	     ceph_cap_string(wanted),
3191	     ceph_cap_string(used),
3192	     ceph_cap_string(dirty));
3193	if (wanted != le32_to_cpu(grant->wanted)) {
3194		dout("mds wanted %s -> %s\n",
3195		     ceph_cap_string(le32_to_cpu(grant->wanted)),
3196		     ceph_cap_string(wanted));
3197		/* imported cap may not have correct mds_wanted */
3198		if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT)
3199			check_caps = 1;
3200	}
3201
 
 
 
 
 
3202	/* revocation, grant, or no-op? */
3203	if (cap->issued & ~newcaps) {
3204		int revoking = cap->issued & ~newcaps;
3205
3206		dout("revocation: %s -> %s (revoking %s)\n",
3207		     ceph_cap_string(cap->issued),
3208		     ceph_cap_string(newcaps),
3209		     ceph_cap_string(revoking));
3210		if (revoking & used & CEPH_CAP_FILE_BUFFER)
3211			writeback = true;  /* initiate writeback; will delay ack */
3212		else if (revoking == CEPH_CAP_FILE_CACHE &&
3213			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3214			 queue_invalidate)
3215			; /* do nothing yet, invalidation will be queued */
3216		else if (cap == ci->i_auth_cap)
3217			check_caps = 1; /* check auth cap only */
3218		else
3219			check_caps = 2; /* check all caps */
3220		cap->issued = newcaps;
3221		cap->implemented |= newcaps;
3222	} else if (cap->issued == newcaps) {
3223		dout("caps unchanged: %s -> %s\n",
3224		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
3225	} else {
3226		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
3227		     ceph_cap_string(newcaps));
3228		/* non-auth MDS is revoking the newly grant caps ? */
3229		if (cap == ci->i_auth_cap &&
3230		    __ceph_caps_revoking_other(ci, cap, newcaps))
3231		    check_caps = 2;
3232
3233		cap->issued = newcaps;
3234		cap->implemented |= newcaps; /* add bits only, to
3235					      * avoid stepping on a
3236					      * pending revocation */
3237		wake = true;
3238	}
3239	BUG_ON(cap->issued & ~cap->implemented);
3240
3241	if (inline_version > 0 && inline_version >= ci->i_inline_version) {
3242		ci->i_inline_version = inline_version;
3243		if (ci->i_inline_version != CEPH_INLINE_NONE &&
3244		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
3245			fill_inline = true;
3246	}
3247
3248	if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
3249		if (newcaps & ~issued)
3250			wake = true;
3251		kick_flushing_inode_caps(mdsc, session, inode);
3252		up_read(&mdsc->snap_rwsem);
3253	} else {
3254		spin_unlock(&ci->i_ceph_lock);
3255	}
3256
3257	if (fill_inline)
3258		ceph_fill_inline_data(inode, NULL, inline_data, inline_len);
3259
3260	if (queue_trunc)
3261		ceph_queue_vmtruncate(inode);
3262
3263	if (writeback)
3264		/*
3265		 * queue inode for writeback: we can't actually call
3266		 * filemap_write_and_wait, etc. from message handler
3267		 * context.
3268		 */
3269		ceph_queue_writeback(inode);
3270	if (queue_invalidate)
3271		ceph_queue_invalidate(inode);
3272	if (deleted_inode)
3273		invalidate_aliases(inode);
3274	if (wake)
3275		wake_up_all(&ci->i_cap_wq);
3276
3277	if (check_caps == 1)
3278		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
3279				session);
3280	else if (check_caps == 2)
3281		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
3282	else
3283		mutex_unlock(&session->s_mutex);
3284}
3285
3286/*
3287 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
3288 * MDS has been safely committed.
3289 */
3290static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
3291				 struct ceph_mds_caps *m,
3292				 struct ceph_mds_session *session,
3293				 struct ceph_cap *cap)
3294	__releases(ci->i_ceph_lock)
3295{
3296	struct ceph_inode_info *ci = ceph_inode(inode);
3297	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3298	struct ceph_cap_flush *cf, *tmp_cf;
3299	LIST_HEAD(to_remove);
3300	unsigned seq = le32_to_cpu(m->seq);
3301	int dirty = le32_to_cpu(m->dirty);
3302	int cleaned = 0;
3303	bool drop = false;
3304	bool wake_ci = false;
3305	bool wake_mdsc = false;
3306
3307	list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) {
3308		if (cf->tid == flush_tid)
3309			cleaned = cf->caps;
3310		if (cf->caps == 0) /* capsnap */
3311			continue;
3312		if (cf->tid <= flush_tid) {
3313			if (__finish_cap_flush(NULL, ci, cf))
3314				wake_ci = true;
3315			list_add_tail(&cf->i_list, &to_remove);
3316		} else {
3317			cleaned &= ~cf->caps;
3318			if (!cleaned)
3319				break;
3320		}
3321	}
3322
3323	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
3324	     " flushing %s -> %s\n",
3325	     inode, session->s_mds, seq, ceph_cap_string(dirty),
3326	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
3327	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
3328
3329	if (list_empty(&to_remove) && !cleaned)
3330		goto out;
3331
3332	ci->i_flushing_caps &= ~cleaned;
3333
3334	spin_lock(&mdsc->cap_dirty_lock);
3335
3336	list_for_each_entry(cf, &to_remove, i_list) {
3337		if (__finish_cap_flush(mdsc, NULL, cf))
3338			wake_mdsc = true;
3339	}
3340
3341	if (ci->i_flushing_caps == 0) {
3342		if (list_empty(&ci->i_cap_flush_list)) {
3343			list_del_init(&ci->i_flushing_item);
3344			if (!list_empty(&session->s_cap_flushing)) {
3345				dout(" mds%d still flushing cap on %p\n",
3346				     session->s_mds,
3347				     &list_first_entry(&session->s_cap_flushing,
3348						struct ceph_inode_info,
3349						i_flushing_item)->vfs_inode);
3350			}
3351		}
3352		mdsc->num_cap_flushing--;
 
3353		dout(" inode %p now !flushing\n", inode);
3354
3355		if (ci->i_dirty_caps == 0) {
3356			dout(" inode %p now clean\n", inode);
3357			BUG_ON(!list_empty(&ci->i_dirty_item));
3358			drop = true;
3359			if (ci->i_wr_ref == 0 &&
3360			    ci->i_wrbuffer_ref_head == 0) {
3361				BUG_ON(!ci->i_head_snapc);
3362				ceph_put_snap_context(ci->i_head_snapc);
3363				ci->i_head_snapc = NULL;
3364			}
3365		} else {
3366			BUG_ON(list_empty(&ci->i_dirty_item));
3367		}
3368	}
3369	spin_unlock(&mdsc->cap_dirty_lock);
 
3370
3371out:
3372	spin_unlock(&ci->i_ceph_lock);
3373
3374	while (!list_empty(&to_remove)) {
3375		cf = list_first_entry(&to_remove,
3376				      struct ceph_cap_flush, i_list);
3377		list_del(&cf->i_list);
3378		ceph_free_cap_flush(cf);
3379	}
3380
3381	if (wake_ci)
3382		wake_up_all(&ci->i_cap_wq);
3383	if (wake_mdsc)
3384		wake_up_all(&mdsc->cap_flushing_wq);
3385	if (drop)
3386		iput(inode);
3387}
3388
3389/*
3390 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
3391 * throw away our cap_snap.
3392 *
3393 * Caller hold s_mutex.
3394 */
3395static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
3396				     struct ceph_mds_caps *m,
3397				     struct ceph_mds_session *session)
3398{
3399	struct ceph_inode_info *ci = ceph_inode(inode);
3400	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3401	u64 follows = le64_to_cpu(m->snap_follows);
3402	struct ceph_cap_snap *capsnap;
3403	bool flushed = false;
3404	bool wake_ci = false;
3405	bool wake_mdsc = false;
3406
3407	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
3408	     inode, ci, session->s_mds, follows);
3409
3410	spin_lock(&ci->i_ceph_lock);
3411	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
3412		if (capsnap->follows == follows) {
3413			if (capsnap->cap_flush.tid != flush_tid) {
3414				dout(" cap_snap %p follows %lld tid %lld !="
3415				     " %lld\n", capsnap, follows,
3416				     flush_tid, capsnap->cap_flush.tid);
3417				break;
3418			}
3419			flushed = true;
 
 
 
 
 
 
 
3420			break;
3421		} else {
3422			dout(" skipping cap_snap %p follows %lld\n",
3423			     capsnap, capsnap->follows);
3424		}
3425	}
3426	if (flushed) {
3427		WARN_ON(capsnap->dirty_pages || capsnap->writing);
3428		dout(" removing %p cap_snap %p follows %lld\n",
3429		     inode, capsnap, follows);
3430		list_del(&capsnap->ci_item);
3431		if (__finish_cap_flush(NULL, ci, &capsnap->cap_flush))
3432			wake_ci = true;
3433
3434		spin_lock(&mdsc->cap_dirty_lock);
3435
3436		if (list_empty(&ci->i_cap_flush_list))
3437			list_del_init(&ci->i_flushing_item);
3438
3439		if (__finish_cap_flush(mdsc, NULL, &capsnap->cap_flush))
3440			wake_mdsc = true;
3441
3442		spin_unlock(&mdsc->cap_dirty_lock);
3443	}
3444	spin_unlock(&ci->i_ceph_lock);
3445	if (flushed) {
3446		ceph_put_snap_context(capsnap->context);
3447		ceph_put_cap_snap(capsnap);
3448		if (wake_ci)
3449			wake_up_all(&ci->i_cap_wq);
3450		if (wake_mdsc)
3451			wake_up_all(&mdsc->cap_flushing_wq);
3452		iput(inode);
3453	}
3454}
3455
3456/*
3457 * Handle TRUNC from MDS, indicating file truncation.
3458 *
3459 * caller hold s_mutex.
3460 */
3461static void handle_cap_trunc(struct inode *inode,
3462			     struct ceph_mds_caps *trunc,
3463			     struct ceph_mds_session *session)
3464	__releases(ci->i_ceph_lock)
3465{
3466	struct ceph_inode_info *ci = ceph_inode(inode);
3467	int mds = session->s_mds;
3468	int seq = le32_to_cpu(trunc->seq);
3469	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
3470	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
3471	u64 size = le64_to_cpu(trunc->size);
3472	int implemented = 0;
3473	int dirty = __ceph_caps_dirty(ci);
3474	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
3475	int queue_trunc = 0;
3476
3477	issued |= implemented | dirty;
3478
3479	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
3480	     inode, mds, seq, truncate_size, truncate_seq);
3481	queue_trunc = ceph_fill_file_size(inode, issued,
3482					  truncate_seq, truncate_size, size);
3483	spin_unlock(&ci->i_ceph_lock);
3484
3485	if (queue_trunc)
3486		ceph_queue_vmtruncate(inode);
3487}
3488
3489/*
3490 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
3491 * different one.  If we are the most recent migration we've seen (as
3492 * indicated by mseq), make note of the migrating cap bits for the
3493 * duration (until we see the corresponding IMPORT).
3494 *
3495 * caller holds s_mutex
3496 */
3497static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
3498			      struct ceph_mds_cap_peer *ph,
3499			      struct ceph_mds_session *session)
3500{
3501	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
3502	struct ceph_mds_session *tsession = NULL;
3503	struct ceph_cap *cap, *tcap, *new_cap = NULL;
3504	struct ceph_inode_info *ci = ceph_inode(inode);
3505	u64 t_cap_id;
3506	unsigned mseq = le32_to_cpu(ex->migrate_seq);
3507	unsigned t_seq, t_mseq;
3508	int target, issued;
3509	int mds = session->s_mds;
 
 
 
 
3510
3511	if (ph) {
3512		t_cap_id = le64_to_cpu(ph->cap_id);
3513		t_seq = le32_to_cpu(ph->seq);
3514		t_mseq = le32_to_cpu(ph->mseq);
3515		target = le32_to_cpu(ph->mds);
3516	} else {
3517		t_cap_id = t_seq = t_mseq = 0;
3518		target = -1;
3519	}
3520
3521	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
3522	     inode, ci, mds, mseq, target);
3523retry:
3524	spin_lock(&ci->i_ceph_lock);
3525	cap = __get_cap_for_mds(ci, mds);
3526	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
3527		goto out_unlock;
3528
3529	if (target < 0) {
3530		__ceph_remove_cap(cap, false);
3531		if (!ci->i_auth_cap)
3532			ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
3533		goto out_unlock;
3534	}
3535
3536	/*
3537	 * now we know we haven't received the cap import message yet
3538	 * because the exported cap still exist.
3539	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3540
3541	issued = cap->issued;
3542	if (issued != cap->implemented)
3543		pr_err_ratelimited("handle_cap_export: issued != implemented: "
3544				"ino (%llx.%llx) mds%d seq %d mseq %d "
3545				"issued %s implemented %s\n",
3546				ceph_vinop(inode), mds, cap->seq, cap->mseq,
3547				ceph_cap_string(issued),
3548				ceph_cap_string(cap->implemented));
3549
3550
3551	tcap = __get_cap_for_mds(ci, target);
3552	if (tcap) {
3553		/* already have caps from the target */
3554		if (tcap->cap_id == t_cap_id &&
3555		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
3556			dout(" updating import cap %p mds%d\n", tcap, target);
3557			tcap->cap_id = t_cap_id;
3558			tcap->seq = t_seq - 1;
3559			tcap->issue_seq = t_seq - 1;
3560			tcap->mseq = t_mseq;
3561			tcap->issued |= issued;
3562			tcap->implemented |= issued;
3563			if (cap == ci->i_auth_cap)
3564				ci->i_auth_cap = tcap;
3565
3566			if (!list_empty(&ci->i_cap_flush_list) &&
3567			    ci->i_auth_cap == tcap) {
3568				spin_lock(&mdsc->cap_dirty_lock);
3569				list_move_tail(&ci->i_flushing_item,
3570					       &tcap->session->s_cap_flushing);
3571				spin_unlock(&mdsc->cap_dirty_lock);
3572			}
3573		}
3574		__ceph_remove_cap(cap, false);
3575		goto out_unlock;
3576	} else if (tsession) {
3577		/* add placeholder for the export tagert */
3578		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
3579		tcap = new_cap;
3580		ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
3581			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
3582
3583		if (!list_empty(&ci->i_cap_flush_list) &&
3584		    ci->i_auth_cap == tcap) {
 
 
3585			spin_lock(&mdsc->cap_dirty_lock);
3586			list_move_tail(&ci->i_flushing_item,
3587				       &tcap->session->s_cap_flushing);
 
 
 
 
3588			spin_unlock(&mdsc->cap_dirty_lock);
3589		}
3590
3591		__ceph_remove_cap(cap, false);
3592		goto out_unlock;
3593	}
3594
3595	spin_unlock(&ci->i_ceph_lock);
3596	mutex_unlock(&session->s_mutex);
3597
3598	/* open target session */
3599	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
3600	if (!IS_ERR(tsession)) {
3601		if (mds > target) {
3602			mutex_lock(&session->s_mutex);
3603			mutex_lock_nested(&tsession->s_mutex,
3604					  SINGLE_DEPTH_NESTING);
3605		} else {
3606			mutex_lock(&tsession->s_mutex);
3607			mutex_lock_nested(&session->s_mutex,
3608					  SINGLE_DEPTH_NESTING);
3609		}
3610		new_cap = ceph_get_cap(mdsc, NULL);
3611	} else {
3612		WARN_ON(1);
3613		tsession = NULL;
3614		target = -1;
3615	}
3616	goto retry;
3617
3618out_unlock:
3619	spin_unlock(&ci->i_ceph_lock);
3620	mutex_unlock(&session->s_mutex);
3621	if (tsession) {
3622		mutex_unlock(&tsession->s_mutex);
3623		ceph_put_mds_session(tsession);
3624	}
3625	if (new_cap)
3626		ceph_put_cap(mdsc, new_cap);
3627}
3628
3629/*
3630 * Handle cap IMPORT.
 
3631 *
3632 * caller holds s_mutex. acquires i_ceph_lock
3633 */
3634static void handle_cap_import(struct ceph_mds_client *mdsc,
3635			      struct inode *inode, struct ceph_mds_caps *im,
3636			      struct ceph_mds_cap_peer *ph,
3637			      struct ceph_mds_session *session,
3638			      struct ceph_cap **target_cap, int *old_issued)
3639	__acquires(ci->i_ceph_lock)
3640{
3641	struct ceph_inode_info *ci = ceph_inode(inode);
3642	struct ceph_cap *cap, *ocap, *new_cap = NULL;
3643	int mds = session->s_mds;
3644	int issued;
3645	unsigned caps = le32_to_cpu(im->caps);
3646	unsigned wanted = le32_to_cpu(im->wanted);
3647	unsigned seq = le32_to_cpu(im->seq);
3648	unsigned mseq = le32_to_cpu(im->migrate_seq);
3649	u64 realmino = le64_to_cpu(im->realm);
3650	u64 cap_id = le64_to_cpu(im->cap_id);
3651	u64 p_cap_id;
3652	int peer;
3653
3654	if (ph) {
3655		p_cap_id = le64_to_cpu(ph->cap_id);
3656		peer = le32_to_cpu(ph->mds);
3657	} else {
3658		p_cap_id = 0;
3659		peer = -1;
3660	}
3661
3662	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
3663	     inode, ci, mds, mseq, peer);
3664
3665retry:
3666	spin_lock(&ci->i_ceph_lock);
3667	cap = __get_cap_for_mds(ci, mds);
3668	if (!cap) {
3669		if (!new_cap) {
3670			spin_unlock(&ci->i_ceph_lock);
3671			new_cap = ceph_get_cap(mdsc, NULL);
3672			goto retry;
3673		}
3674		cap = new_cap;
3675	} else {
3676		if (new_cap) {
3677			ceph_put_cap(mdsc, new_cap);
3678			new_cap = NULL;
3679		}
3680	}
3681
3682	__ceph_caps_issued(ci, &issued);
3683	issued |= __ceph_caps_dirty(ci);
3684
3685	ceph_add_cap(inode, session, cap_id, -1, caps, wanted, seq, mseq,
3686		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
3687
3688	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
3689	if (ocap && ocap->cap_id == p_cap_id) {
3690		dout(" remove export cap %p mds%d flags %d\n",
3691		     ocap, peer, ph->flags);
3692		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
3693		    (ocap->seq != le32_to_cpu(ph->seq) ||
3694		     ocap->mseq != le32_to_cpu(ph->mseq))) {
3695			pr_err_ratelimited("handle_cap_import: "
3696					"mismatched seq/mseq: ino (%llx.%llx) "
3697					"mds%d seq %d mseq %d importer mds%d "
3698					"has peer seq %d mseq %d\n",
3699					ceph_vinop(inode), peer, ocap->seq,
3700					ocap->mseq, mds, le32_to_cpu(ph->seq),
3701					le32_to_cpu(ph->mseq));
3702		}
3703		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
3704	}
3705
3706	/* make sure we re-request max_size, if necessary */
 
3707	ci->i_requested_max_size = 0;
3708
3709	*old_issued = issued;
3710	*target_cap = cap;
3711}
3712
3713/*
3714 * Handle a caps message from the MDS.
3715 *
3716 * Identify the appropriate session, inode, and call the right handler
3717 * based on the cap op.
3718 */
3719void ceph_handle_caps(struct ceph_mds_session *session,
3720		      struct ceph_msg *msg)
3721{
3722	struct ceph_mds_client *mdsc = session->s_mdsc;
3723	struct super_block *sb = mdsc->fsc->sb;
3724	struct inode *inode;
3725	struct ceph_inode_info *ci;
3726	struct ceph_cap *cap;
3727	struct ceph_mds_caps *h;
3728	struct ceph_mds_cap_peer *peer = NULL;
3729	struct ceph_snap_realm *realm = NULL;
3730	struct ceph_string *pool_ns = NULL;
3731	int mds = session->s_mds;
3732	int op, issued;
3733	u32 seq, mseq;
3734	struct ceph_vino vino;
 
 
3735	u64 tid;
3736	u64 inline_version = 0;
3737	void *inline_data = NULL;
3738	u32  inline_len = 0;
3739	void *snaptrace;
3740	size_t snaptrace_len;
3741	void *p, *end;
 
 
3742
3743	dout("handle_caps from mds%d\n", mds);
3744
3745	/* decode */
3746	end = msg->front.iov_base + msg->front.iov_len;
3747	tid = le64_to_cpu(msg->hdr.tid);
3748	if (msg->front.iov_len < sizeof(*h))
3749		goto bad;
3750	h = msg->front.iov_base;
3751	op = le32_to_cpu(h->op);
3752	vino.ino = le64_to_cpu(h->ino);
3753	vino.snap = CEPH_NOSNAP;
 
3754	seq = le32_to_cpu(h->seq);
3755	mseq = le32_to_cpu(h->migrate_seq);
 
 
3756
3757	snaptrace = h + 1;
3758	snaptrace_len = le32_to_cpu(h->snap_trace_len);
3759	p = snaptrace + snaptrace_len;
3760
3761	if (le16_to_cpu(msg->hdr.version) >= 2) {
3762		u32 flock_len;
 
 
 
3763		ceph_decode_32_safe(&p, end, flock_len, bad);
3764		if (p + flock_len > end)
3765			goto bad;
3766		p += flock_len;
3767	}
3768
3769	if (le16_to_cpu(msg->hdr.version) >= 3) {
3770		if (op == CEPH_CAP_OP_IMPORT) {
3771			if (p + sizeof(*peer) > end)
3772				goto bad;
3773			peer = p;
3774			p += sizeof(*peer);
3775		} else if (op == CEPH_CAP_OP_EXPORT) {
3776			/* recorded in unused fields */
3777			peer = (void *)&h->size;
3778		}
3779	}
3780
3781	if (le16_to_cpu(msg->hdr.version) >= 4) {
3782		ceph_decode_64_safe(&p, end, inline_version, bad);
3783		ceph_decode_32_safe(&p, end, inline_len, bad);
3784		if (p + inline_len > end)
3785			goto bad;
3786		inline_data = p;
3787		p += inline_len;
3788	}
3789
3790	if (le16_to_cpu(msg->hdr.version) >= 5) {
3791		struct ceph_osd_client	*osdc = &mdsc->fsc->client->osdc;
3792		u32			epoch_barrier;
3793
3794		ceph_decode_32_safe(&p, end, epoch_barrier, bad);
3795		ceph_osdc_update_epoch_barrier(osdc, epoch_barrier);
3796	}
3797
3798	if (le16_to_cpu(msg->hdr.version) >= 8) {
3799		u64 flush_tid;
3800		u32 caller_uid, caller_gid;
3801		u32 pool_ns_len;
3802
3803		/* version >= 6 */
3804		ceph_decode_64_safe(&p, end, flush_tid, bad);
3805		/* version >= 7 */
3806		ceph_decode_32_safe(&p, end, caller_uid, bad);
3807		ceph_decode_32_safe(&p, end, caller_gid, bad);
3808		/* version >= 8 */
3809		ceph_decode_32_safe(&p, end, pool_ns_len, bad);
3810		if (pool_ns_len > 0) {
3811			ceph_decode_need(&p, end, pool_ns_len, bad);
3812			pool_ns = ceph_find_or_create_string(p, pool_ns_len);
3813			p += pool_ns_len;
3814		}
3815	}
3816
3817	/* lookup ino */
3818	inode = ceph_find_inode(sb, vino);
3819	ci = ceph_inode(inode);
3820	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
3821	     vino.snap, inode);
3822
3823	mutex_lock(&session->s_mutex);
3824	session->s_seq++;
3825	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
3826	     (unsigned)seq);
3827
3828	if (!inode) {
3829		dout(" i don't have ino %llx\n", vino.ino);
3830
3831		if (op == CEPH_CAP_OP_IMPORT) {
3832			cap = ceph_get_cap(mdsc, NULL);
3833			cap->cap_ino = vino.ino;
3834			cap->queue_release = 1;
3835			cap->cap_id = le64_to_cpu(h->cap_id);
3836			cap->mseq = mseq;
3837			cap->seq = seq;
3838			cap->issue_seq = seq;
3839			spin_lock(&session->s_cap_lock);
3840			list_add_tail(&cap->session_caps,
3841					&session->s_cap_releases);
3842			session->s_num_cap_releases++;
3843			spin_unlock(&session->s_cap_lock);
3844		}
3845		goto flush_cap_releases;
3846	}
3847
3848	/* these will work even if we don't have a cap yet */
3849	switch (op) {
3850	case CEPH_CAP_OP_FLUSHSNAP_ACK:
3851		handle_cap_flushsnap_ack(inode, tid, h, session);
3852		goto done;
3853
3854	case CEPH_CAP_OP_EXPORT:
3855		handle_cap_export(inode, h, peer, session);
3856		goto done_unlocked;
3857
3858	case CEPH_CAP_OP_IMPORT:
3859		realm = NULL;
3860		if (snaptrace_len) {
3861			down_write(&mdsc->snap_rwsem);
3862			ceph_update_snap_trace(mdsc, snaptrace,
3863					       snaptrace + snaptrace_len,
3864					       false, &realm);
3865			downgrade_write(&mdsc->snap_rwsem);
3866		} else {
3867			down_read(&mdsc->snap_rwsem);
3868		}
3869		handle_cap_import(mdsc, inode, h, peer, session,
3870				  &cap, &issued);
3871		handle_cap_grant(mdsc, inode, h, &pool_ns,
3872				 inline_version, inline_data, inline_len,
3873				 msg->middle, session, cap, issued);
3874		if (realm)
3875			ceph_put_snap_realm(mdsc, realm);
3876		goto done_unlocked;
3877	}
3878
3879	/* the rest require a cap */
3880	spin_lock(&ci->i_ceph_lock);
3881	cap = __get_cap_for_mds(ceph_inode(inode), mds);
3882	if (!cap) {
3883		dout(" no cap on %p ino %llx.%llx from mds%d\n",
3884		     inode, ceph_ino(inode), ceph_snap(inode), mds);
3885		spin_unlock(&ci->i_ceph_lock);
3886		goto flush_cap_releases;
3887	}
3888
3889	/* note that each of these drops i_ceph_lock for us */
3890	switch (op) {
3891	case CEPH_CAP_OP_REVOKE:
3892	case CEPH_CAP_OP_GRANT:
3893		__ceph_caps_issued(ci, &issued);
3894		issued |= __ceph_caps_dirty(ci);
3895		handle_cap_grant(mdsc, inode, h, &pool_ns,
3896				 inline_version, inline_data, inline_len,
3897				 msg->middle, session, cap, issued);
3898		goto done_unlocked;
3899
3900	case CEPH_CAP_OP_FLUSH_ACK:
3901		handle_cap_flush_ack(inode, tid, h, session, cap);
3902		break;
3903
3904	case CEPH_CAP_OP_TRUNC:
3905		handle_cap_trunc(inode, h, session);
3906		break;
3907
3908	default:
3909		spin_unlock(&ci->i_ceph_lock);
3910		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
3911		       ceph_cap_op_name(op));
3912	}
3913
3914	goto done;
3915
3916flush_cap_releases:
3917	/*
3918	 * send any cap release message to try to move things
3919	 * along for the mds (who clearly thinks we still have this
3920	 * cap).
3921	 */
 
3922	ceph_send_cap_releases(mdsc, session);
3923
3924done:
3925	mutex_unlock(&session->s_mutex);
3926done_unlocked:
3927	iput(inode);
3928	ceph_put_string(pool_ns);
 
 
3929	return;
3930
3931bad:
3932	pr_err("ceph_handle_caps: corrupt message\n");
3933	ceph_msg_dump(msg);
3934	return;
3935}
3936
3937/*
3938 * Delayed work handler to process end of delayed cap release LRU list.
3939 */
3940void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
3941{
3942	struct inode *inode;
3943	struct ceph_inode_info *ci;
3944	int flags = CHECK_CAPS_NODELAY;
3945
3946	dout("check_delayed_caps\n");
3947	while (1) {
3948		spin_lock(&mdsc->cap_delay_lock);
3949		if (list_empty(&mdsc->cap_delay_list))
3950			break;
3951		ci = list_first_entry(&mdsc->cap_delay_list,
3952				      struct ceph_inode_info,
3953				      i_cap_delay_list);
3954		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
3955		    time_before(jiffies, ci->i_hold_caps_max))
3956			break;
3957		list_del_init(&ci->i_cap_delay_list);
3958
3959		inode = igrab(&ci->vfs_inode);
3960		spin_unlock(&mdsc->cap_delay_lock);
3961
3962		if (inode) {
3963			dout("check_delayed_caps on %p\n", inode);
3964			ceph_check_caps(ci, flags, NULL);
3965			iput(inode);
3966		}
3967	}
3968	spin_unlock(&mdsc->cap_delay_lock);
3969}
3970
3971/*
3972 * Flush all dirty caps to the mds
3973 */
3974void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
3975{
3976	struct ceph_inode_info *ci;
3977	struct inode *inode;
3978
3979	dout("flush_dirty_caps\n");
3980	spin_lock(&mdsc->cap_dirty_lock);
3981	while (!list_empty(&mdsc->cap_dirty)) {
3982		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
3983				      i_dirty_item);
3984		inode = &ci->vfs_inode;
3985		ihold(inode);
3986		dout("flush_dirty_caps %p\n", inode);
3987		spin_unlock(&mdsc->cap_dirty_lock);
3988		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
3989		iput(inode);
3990		spin_lock(&mdsc->cap_dirty_lock);
3991	}
3992	spin_unlock(&mdsc->cap_dirty_lock);
3993	dout("flush_dirty_caps done\n");
3994}
3995
3996void __ceph_get_fmode(struct ceph_inode_info *ci, int fmode)
3997{
3998	int i;
3999	int bits = (fmode << 1) | 1;
4000	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4001		if (bits & (1 << i))
4002			ci->i_nr_by_mode[i]++;
4003	}
4004}
4005
4006/*
4007 * Drop open file reference.  If we were the last open file,
4008 * we may need to release capabilities to the MDS (or schedule
4009 * their delayed release).
4010 */
4011void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
4012{
4013	int i, last = 0;
4014	int bits = (fmode << 1) | 1;
 
4015	spin_lock(&ci->i_ceph_lock);
4016	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4017		if (bits & (1 << i)) {
4018			BUG_ON(ci->i_nr_by_mode[i] == 0);
4019			if (--ci->i_nr_by_mode[i] == 0)
4020				last++;
4021		}
4022	}
4023	dout("put_fmode %p fmode %d {%d,%d,%d,%d}\n",
4024	     &ci->vfs_inode, fmode,
4025	     ci->i_nr_by_mode[0], ci->i_nr_by_mode[1],
4026	     ci->i_nr_by_mode[2], ci->i_nr_by_mode[3]);
4027	spin_unlock(&ci->i_ceph_lock);
4028
4029	if (last && ci->i_vino.snap == CEPH_NOSNAP)
4030		ceph_check_caps(ci, 0, NULL);
4031}
4032
4033/*
4034 * For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps. If it
4035 * looks like the link count will hit 0, drop any other caps (other
4036 * than PIN) we don't specifically want (due to the file still being
4037 * open).
4038 */
4039int ceph_drop_caps_for_unlink(struct inode *inode)
4040{
4041	struct ceph_inode_info *ci = ceph_inode(inode);
4042	int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
4043
4044	spin_lock(&ci->i_ceph_lock);
4045	if (inode->i_nlink == 1) {
4046		drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
4047
4048		ci->i_ceph_flags |= CEPH_I_NODELAY;
4049		if (__ceph_caps_dirty(ci)) {
4050			struct ceph_mds_client *mdsc =
4051				ceph_inode_to_client(inode)->mdsc;
4052			__cap_delay_requeue_front(mdsc, ci);
4053		}
4054	}
4055	spin_unlock(&ci->i_ceph_lock);
4056	return drop;
4057}
4058
4059/*
4060 * Helpers for embedding cap and dentry lease releases into mds
4061 * requests.
4062 *
4063 * @force is used by dentry_release (below) to force inclusion of a
4064 * record for the directory inode, even when there aren't any caps to
4065 * drop.
4066 */
4067int ceph_encode_inode_release(void **p, struct inode *inode,
4068			      int mds, int drop, int unless, int force)
4069{
4070	struct ceph_inode_info *ci = ceph_inode(inode);
4071	struct ceph_cap *cap;
4072	struct ceph_mds_request_release *rel = *p;
4073	int used, dirty;
4074	int ret = 0;
4075
4076	spin_lock(&ci->i_ceph_lock);
4077	used = __ceph_caps_used(ci);
4078	dirty = __ceph_caps_dirty(ci);
4079
4080	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
4081	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
4082	     ceph_cap_string(unless));
4083
4084	/* only drop unused, clean caps */
4085	drop &= ~(used | dirty);
4086
4087	cap = __get_cap_for_mds(ci, mds);
4088	if (cap && __cap_is_valid(cap)) {
4089		unless &= cap->issued;
4090		if (unless) {
4091			if (unless & CEPH_CAP_AUTH_EXCL)
4092				drop &= ~CEPH_CAP_AUTH_SHARED;
4093			if (unless & CEPH_CAP_LINK_EXCL)
4094				drop &= ~CEPH_CAP_LINK_SHARED;
4095			if (unless & CEPH_CAP_XATTR_EXCL)
4096				drop &= ~CEPH_CAP_XATTR_SHARED;
4097			if (unless & CEPH_CAP_FILE_EXCL)
4098				drop &= ~CEPH_CAP_FILE_SHARED;
4099		}
4100
4101		if (force || (cap->issued & drop)) {
4102			if (cap->issued & drop) {
4103				int wanted = __ceph_caps_wanted(ci);
4104				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
4105					wanted |= cap->mds_wanted;
4106				dout("encode_inode_release %p cap %p "
4107				     "%s -> %s, wanted %s -> %s\n", inode, cap,
4108				     ceph_cap_string(cap->issued),
4109				     ceph_cap_string(cap->issued & ~drop),
4110				     ceph_cap_string(cap->mds_wanted),
4111				     ceph_cap_string(wanted));
4112
4113				cap->issued &= ~drop;
4114				cap->implemented &= ~drop;
4115				cap->mds_wanted = wanted;
 
 
 
 
 
 
 
 
4116			} else {
4117				dout("encode_inode_release %p cap %p %s"
4118				     " (force)\n", inode, cap,
4119				     ceph_cap_string(cap->issued));
4120			}
4121
4122			rel->ino = cpu_to_le64(ceph_ino(inode));
4123			rel->cap_id = cpu_to_le64(cap->cap_id);
4124			rel->seq = cpu_to_le32(cap->seq);
4125			rel->issue_seq = cpu_to_le32(cap->issue_seq);
4126			rel->mseq = cpu_to_le32(cap->mseq);
4127			rel->caps = cpu_to_le32(cap->implemented);
4128			rel->wanted = cpu_to_le32(cap->mds_wanted);
4129			rel->dname_len = 0;
4130			rel->dname_seq = 0;
4131			*p += sizeof(*rel);
4132			ret = 1;
4133		} else {
4134			dout("encode_inode_release %p cap %p %s (noop)\n",
4135			     inode, cap, ceph_cap_string(cap->issued));
4136		}
4137	}
4138	spin_unlock(&ci->i_ceph_lock);
4139	return ret;
4140}
4141
4142int ceph_encode_dentry_release(void **p, struct dentry *dentry,
4143			       struct inode *dir,
4144			       int mds, int drop, int unless)
4145{
4146	struct dentry *parent = NULL;
4147	struct ceph_mds_request_release *rel = *p;
4148	struct ceph_dentry_info *di = ceph_dentry(dentry);
4149	int force = 0;
4150	int ret;
4151
4152	/*
4153	 * force an record for the directory caps if we have a dentry lease.
4154	 * this is racy (can't take i_ceph_lock and d_lock together), but it
4155	 * doesn't have to be perfect; the mds will revoke anything we don't
4156	 * release.
4157	 */
4158	spin_lock(&dentry->d_lock);
4159	if (di->lease_session && di->lease_session->s_mds == mds)
4160		force = 1;
4161	if (!dir) {
4162		parent = dget(dentry->d_parent);
4163		dir = d_inode(parent);
4164	}
4165	spin_unlock(&dentry->d_lock);
4166
4167	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
4168	dput(parent);
4169
4170	spin_lock(&dentry->d_lock);
4171	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
4172		dout("encode_dentry_release %p mds%d seq %d\n",
4173		     dentry, mds, (int)di->lease_seq);
4174		rel->dname_len = cpu_to_le32(dentry->d_name.len);
4175		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
4176		*p += dentry->d_name.len;
4177		rel->dname_seq = cpu_to_le32(di->lease_seq);
4178		__ceph_mdsc_drop_dentry_lease(dentry);
4179	}
4180	spin_unlock(&dentry->d_lock);
4181	return ret;
4182}
v3.5.6
 
   1#include <linux/ceph/ceph_debug.h>
   2
   3#include <linux/fs.h>
   4#include <linux/kernel.h>
   5#include <linux/sched.h>
   6#include <linux/slab.h>
   7#include <linux/vmalloc.h>
   8#include <linux/wait.h>
   9#include <linux/writeback.h>
  10
  11#include "super.h"
  12#include "mds_client.h"
 
  13#include <linux/ceph/decode.h>
  14#include <linux/ceph/messenger.h>
  15
  16/*
  17 * Capability management
  18 *
  19 * The Ceph metadata servers control client access to inode metadata
  20 * and file data by issuing capabilities, granting clients permission
  21 * to read and/or write both inode field and file data to OSDs
  22 * (storage nodes).  Each capability consists of a set of bits
  23 * indicating which operations are allowed.
  24 *
  25 * If the client holds a *_SHARED cap, the client has a coherent value
  26 * that can be safely read from the cached inode.
  27 *
  28 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
  29 * client is allowed to change inode attributes (e.g., file size,
  30 * mtime), note its dirty state in the ceph_cap, and asynchronously
  31 * flush that metadata change to the MDS.
  32 *
  33 * In the event of a conflicting operation (perhaps by another
  34 * client), the MDS will revoke the conflicting client capabilities.
  35 *
  36 * In order for a client to cache an inode, it must hold a capability
  37 * with at least one MDS server.  When inodes are released, release
  38 * notifications are batched and periodically sent en masse to the MDS
  39 * cluster to release server state.
  40 */
  41
 
 
 
 
 
  42
  43/*
  44 * Generate readable cap strings for debugging output.
  45 */
  46#define MAX_CAP_STR 20
  47static char cap_str[MAX_CAP_STR][40];
  48static DEFINE_SPINLOCK(cap_str_lock);
  49static int last_cap_str;
  50
  51static char *gcap_string(char *s, int c)
  52{
  53	if (c & CEPH_CAP_GSHARED)
  54		*s++ = 's';
  55	if (c & CEPH_CAP_GEXCL)
  56		*s++ = 'x';
  57	if (c & CEPH_CAP_GCACHE)
  58		*s++ = 'c';
  59	if (c & CEPH_CAP_GRD)
  60		*s++ = 'r';
  61	if (c & CEPH_CAP_GWR)
  62		*s++ = 'w';
  63	if (c & CEPH_CAP_GBUFFER)
  64		*s++ = 'b';
  65	if (c & CEPH_CAP_GLAZYIO)
  66		*s++ = 'l';
  67	return s;
  68}
  69
  70const char *ceph_cap_string(int caps)
  71{
  72	int i;
  73	char *s;
  74	int c;
  75
  76	spin_lock(&cap_str_lock);
  77	i = last_cap_str++;
  78	if (last_cap_str == MAX_CAP_STR)
  79		last_cap_str = 0;
  80	spin_unlock(&cap_str_lock);
  81
  82	s = cap_str[i];
  83
  84	if (caps & CEPH_CAP_PIN)
  85		*s++ = 'p';
  86
  87	c = (caps >> CEPH_CAP_SAUTH) & 3;
  88	if (c) {
  89		*s++ = 'A';
  90		s = gcap_string(s, c);
  91	}
  92
  93	c = (caps >> CEPH_CAP_SLINK) & 3;
  94	if (c) {
  95		*s++ = 'L';
  96		s = gcap_string(s, c);
  97	}
  98
  99	c = (caps >> CEPH_CAP_SXATTR) & 3;
 100	if (c) {
 101		*s++ = 'X';
 102		s = gcap_string(s, c);
 103	}
 104
 105	c = caps >> CEPH_CAP_SFILE;
 106	if (c) {
 107		*s++ = 'F';
 108		s = gcap_string(s, c);
 109	}
 110
 111	if (s == cap_str[i])
 112		*s++ = '-';
 113	*s = 0;
 114	return cap_str[i];
 115}
 116
 117void ceph_caps_init(struct ceph_mds_client *mdsc)
 118{
 119	INIT_LIST_HEAD(&mdsc->caps_list);
 120	spin_lock_init(&mdsc->caps_list_lock);
 121}
 122
 123void ceph_caps_finalize(struct ceph_mds_client *mdsc)
 124{
 125	struct ceph_cap *cap;
 126
 127	spin_lock(&mdsc->caps_list_lock);
 128	while (!list_empty(&mdsc->caps_list)) {
 129		cap = list_first_entry(&mdsc->caps_list,
 130				       struct ceph_cap, caps_item);
 131		list_del(&cap->caps_item);
 132		kmem_cache_free(ceph_cap_cachep, cap);
 133	}
 134	mdsc->caps_total_count = 0;
 135	mdsc->caps_avail_count = 0;
 136	mdsc->caps_use_count = 0;
 137	mdsc->caps_reserve_count = 0;
 138	mdsc->caps_min_count = 0;
 139	spin_unlock(&mdsc->caps_list_lock);
 140}
 141
 142void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
 143{
 144	spin_lock(&mdsc->caps_list_lock);
 145	mdsc->caps_min_count += delta;
 146	BUG_ON(mdsc->caps_min_count < 0);
 147	spin_unlock(&mdsc->caps_list_lock);
 148}
 149
 
 
 
 150int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 151		      struct ceph_cap_reservation *ctx, int need)
 152{
 153	int i;
 154	struct ceph_cap *cap;
 155	int have;
 156	int alloc = 0;
 
 
 
 157	LIST_HEAD(newcaps);
 158	int ret = 0;
 159
 160	dout("reserve caps ctx=%p need=%d\n", ctx, need);
 161
 162	/* first reserve any caps that are already allocated */
 163	spin_lock(&mdsc->caps_list_lock);
 164	if (mdsc->caps_avail_count >= need)
 165		have = need;
 166	else
 167		have = mdsc->caps_avail_count;
 168	mdsc->caps_avail_count -= have;
 169	mdsc->caps_reserve_count += have;
 170	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 171					 mdsc->caps_reserve_count +
 172					 mdsc->caps_avail_count);
 173	spin_unlock(&mdsc->caps_list_lock);
 174
 175	for (i = have; i < need; i++) {
 176		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 177		if (!cap) {
 178			ret = -ENOMEM;
 179			goto out_alloc_count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 180		}
 181		list_add(&cap->caps_item, &newcaps);
 182		alloc++;
 
 
 183	}
 184	BUG_ON(have + alloc != need);
 185
 186	spin_lock(&mdsc->caps_list_lock);
 187	mdsc->caps_total_count += alloc;
 188	mdsc->caps_reserve_count += alloc;
 189	list_splice(&newcaps, &mdsc->caps_list);
 190
 191	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 192					 mdsc->caps_reserve_count +
 193					 mdsc->caps_avail_count);
 194	spin_unlock(&mdsc->caps_list_lock);
 195
 196	ctx->count = need;
 197	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 198	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 199	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 200	return 0;
 201
 202out_alloc_count:
 203	/* we didn't manage to reserve as much as we needed */
 204	pr_warning("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
 205		   ctx, need, have);
 206	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 207}
 208
 209int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 210			struct ceph_cap_reservation *ctx)
 211{
 
 
 
 212	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
 213	if (ctx->count) {
 214		spin_lock(&mdsc->caps_list_lock);
 215		BUG_ON(mdsc->caps_reserve_count < ctx->count);
 216		mdsc->caps_reserve_count -= ctx->count;
 217		mdsc->caps_avail_count += ctx->count;
 
 
 
 
 
 
 
 
 
 
 
 218		ctx->count = 0;
 219		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
 220		     mdsc->caps_total_count, mdsc->caps_use_count,
 221		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 222		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 223						 mdsc->caps_reserve_count +
 224						 mdsc->caps_avail_count);
 225		spin_unlock(&mdsc->caps_list_lock);
 226	}
 227	return 0;
 228}
 229
 230static struct ceph_cap *get_cap(struct ceph_mds_client *mdsc,
 231				struct ceph_cap_reservation *ctx)
 232{
 233	struct ceph_cap *cap = NULL;
 234
 235	/* temporary, until we do something about cap import/export */
 236	if (!ctx) {
 237		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 238		if (cap) {
 
 239			mdsc->caps_use_count++;
 240			mdsc->caps_total_count++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 241		}
 
 242		return cap;
 243	}
 244
 245	spin_lock(&mdsc->caps_list_lock);
 246	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
 247	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
 248	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 249	BUG_ON(!ctx->count);
 250	BUG_ON(ctx->count > mdsc->caps_reserve_count);
 251	BUG_ON(list_empty(&mdsc->caps_list));
 252
 253	ctx->count--;
 254	mdsc->caps_reserve_count--;
 255	mdsc->caps_use_count++;
 256
 257	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
 258	list_del(&cap->caps_item);
 259
 260	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 261	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 262	spin_unlock(&mdsc->caps_list_lock);
 263	return cap;
 264}
 265
 266void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
 267{
 268	spin_lock(&mdsc->caps_list_lock);
 269	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
 270	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
 271	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 272	mdsc->caps_use_count--;
 273	/*
 274	 * Keep some preallocated caps around (ceph_min_count), to
 275	 * avoid lots of free/alloc churn.
 276	 */
 277	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
 278				      mdsc->caps_min_count) {
 279		mdsc->caps_total_count--;
 280		kmem_cache_free(ceph_cap_cachep, cap);
 281	} else {
 282		mdsc->caps_avail_count++;
 283		list_add(&cap->caps_item, &mdsc->caps_list);
 284	}
 285
 286	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 287	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 288	spin_unlock(&mdsc->caps_list_lock);
 289}
 290
 291void ceph_reservation_status(struct ceph_fs_client *fsc,
 292			     int *total, int *avail, int *used, int *reserved,
 293			     int *min)
 294{
 295	struct ceph_mds_client *mdsc = fsc->mdsc;
 296
 
 
 297	if (total)
 298		*total = mdsc->caps_total_count;
 299	if (avail)
 300		*avail = mdsc->caps_avail_count;
 301	if (used)
 302		*used = mdsc->caps_use_count;
 303	if (reserved)
 304		*reserved = mdsc->caps_reserve_count;
 305	if (min)
 306		*min = mdsc->caps_min_count;
 
 
 307}
 308
 309/*
 310 * Find ceph_cap for given mds, if any.
 311 *
 312 * Called with i_ceph_lock held.
 313 */
 314static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 315{
 316	struct ceph_cap *cap;
 317	struct rb_node *n = ci->i_caps.rb_node;
 318
 319	while (n) {
 320		cap = rb_entry(n, struct ceph_cap, ci_node);
 321		if (mds < cap->mds)
 322			n = n->rb_left;
 323		else if (mds > cap->mds)
 324			n = n->rb_right;
 325		else
 326			return cap;
 327	}
 328	return NULL;
 329}
 330
 331struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 332{
 333	struct ceph_cap *cap;
 334
 335	spin_lock(&ci->i_ceph_lock);
 336	cap = __get_cap_for_mds(ci, mds);
 337	spin_unlock(&ci->i_ceph_lock);
 338	return cap;
 339}
 340
 341/*
 342 * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
 343 */
 344static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
 345{
 346	struct ceph_cap *cap;
 347	int mds = -1;
 348	struct rb_node *p;
 349
 350	/* prefer mds with WR|BUFFER|EXCL caps */
 351	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 352		cap = rb_entry(p, struct ceph_cap, ci_node);
 353		mds = cap->mds;
 354		if (cap->issued & (CEPH_CAP_FILE_WR |
 355				   CEPH_CAP_FILE_BUFFER |
 356				   CEPH_CAP_FILE_EXCL))
 357			break;
 358	}
 359	return mds;
 360}
 361
 362int ceph_get_cap_mds(struct inode *inode)
 363{
 364	struct ceph_inode_info *ci = ceph_inode(inode);
 365	int mds;
 366	spin_lock(&ci->i_ceph_lock);
 367	mds = __ceph_get_cap_mds(ceph_inode(inode));
 368	spin_unlock(&ci->i_ceph_lock);
 369	return mds;
 370}
 371
 372/*
 373 * Called under i_ceph_lock.
 374 */
 375static void __insert_cap_node(struct ceph_inode_info *ci,
 376			      struct ceph_cap *new)
 377{
 378	struct rb_node **p = &ci->i_caps.rb_node;
 379	struct rb_node *parent = NULL;
 380	struct ceph_cap *cap = NULL;
 381
 382	while (*p) {
 383		parent = *p;
 384		cap = rb_entry(parent, struct ceph_cap, ci_node);
 385		if (new->mds < cap->mds)
 386			p = &(*p)->rb_left;
 387		else if (new->mds > cap->mds)
 388			p = &(*p)->rb_right;
 389		else
 390			BUG();
 391	}
 392
 393	rb_link_node(&new->ci_node, parent, p);
 394	rb_insert_color(&new->ci_node, &ci->i_caps);
 395}
 396
 397/*
 398 * (re)set cap hold timeouts, which control the delayed release
 399 * of unused caps back to the MDS.  Should be called on cap use.
 400 */
 401static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
 402			       struct ceph_inode_info *ci)
 403{
 404	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
 405
 406	ci->i_hold_caps_min = round_jiffies(jiffies +
 407					    ma->caps_wanted_delay_min * HZ);
 408	ci->i_hold_caps_max = round_jiffies(jiffies +
 409					    ma->caps_wanted_delay_max * HZ);
 410	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
 411	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
 412}
 413
 414/*
 415 * (Re)queue cap at the end of the delayed cap release list.
 416 *
 417 * If I_FLUSH is set, leave the inode at the front of the list.
 418 *
 419 * Caller holds i_ceph_lock
 420 *    -> we take mdsc->cap_delay_lock
 421 */
 422static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 423				struct ceph_inode_info *ci)
 424{
 425	__cap_set_timeouts(mdsc, ci);
 426	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
 427	     ci->i_ceph_flags, ci->i_hold_caps_max);
 428	if (!mdsc->stopping) {
 429		spin_lock(&mdsc->cap_delay_lock);
 430		if (!list_empty(&ci->i_cap_delay_list)) {
 431			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 432				goto no_change;
 433			list_del_init(&ci->i_cap_delay_list);
 434		}
 435		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 436no_change:
 437		spin_unlock(&mdsc->cap_delay_lock);
 438	}
 439}
 440
 441/*
 442 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 443 * indicating we should send a cap message to flush dirty metadata
 444 * asap, and move to the front of the delayed cap list.
 445 */
 446static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 447				      struct ceph_inode_info *ci)
 448{
 449	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
 450	spin_lock(&mdsc->cap_delay_lock);
 451	ci->i_ceph_flags |= CEPH_I_FLUSH;
 452	if (!list_empty(&ci->i_cap_delay_list))
 453		list_del_init(&ci->i_cap_delay_list);
 454	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 455	spin_unlock(&mdsc->cap_delay_lock);
 456}
 457
 458/*
 459 * Cancel delayed work on cap.
 460 *
 461 * Caller must hold i_ceph_lock.
 462 */
 463static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 464			       struct ceph_inode_info *ci)
 465{
 466	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
 467	if (list_empty(&ci->i_cap_delay_list))
 468		return;
 469	spin_lock(&mdsc->cap_delay_lock);
 470	list_del_init(&ci->i_cap_delay_list);
 471	spin_unlock(&mdsc->cap_delay_lock);
 472}
 473
 474/*
 475 * Common issue checks for add_cap, handle_cap_grant.
 476 */
 477static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 478			      unsigned issued)
 479{
 480	unsigned had = __ceph_caps_issued(ci, NULL);
 481
 482	/*
 483	 * Each time we receive FILE_CACHE anew, we increment
 484	 * i_rdcache_gen.
 485	 */
 486	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 487	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
 488		ci->i_rdcache_gen++;
 
 489
 490	/*
 491	 * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
 492	 * don't know what happened to this directory while we didn't
 493	 * have the cap.
 
 494	 */
 495	if ((issued & CEPH_CAP_FILE_SHARED) &&
 496	    (had & CEPH_CAP_FILE_SHARED) == 0) {
 497		ci->i_shared_gen++;
 498		if (S_ISDIR(ci->vfs_inode.i_mode))
 499			ceph_dir_clear_complete(&ci->vfs_inode);
 
 
 500	}
 501}
 502
 503/*
 504 * Add a capability under the given MDS session.
 505 *
 506 * Caller should hold session snap_rwsem (read) and s_mutex.
 507 *
 508 * @fmode is the open file mode, if we are opening a file, otherwise
 509 * it is < 0.  (This is so we can atomically add the cap and add an
 510 * open file reference to it.)
 511 */
 512int ceph_add_cap(struct inode *inode,
 513		 struct ceph_mds_session *session, u64 cap_id,
 514		 int fmode, unsigned issued, unsigned wanted,
 515		 unsigned seq, unsigned mseq, u64 realmino, int flags,
 516		 struct ceph_cap_reservation *caps_reservation)
 517{
 518	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 519	struct ceph_inode_info *ci = ceph_inode(inode);
 520	struct ceph_cap *new_cap = NULL;
 521	struct ceph_cap *cap;
 522	int mds = session->s_mds;
 523	int actual_wanted;
 524
 525	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 526	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 527
 528	/*
 529	 * If we are opening the file, include file mode wanted bits
 530	 * in wanted.
 531	 */
 532	if (fmode >= 0)
 533		wanted |= ceph_caps_for_mode(fmode);
 534
 535retry:
 536	spin_lock(&ci->i_ceph_lock);
 537	cap = __get_cap_for_mds(ci, mds);
 538	if (!cap) {
 539		if (new_cap) {
 540			cap = new_cap;
 541			new_cap = NULL;
 542		} else {
 543			spin_unlock(&ci->i_ceph_lock);
 544			new_cap = get_cap(mdsc, caps_reservation);
 545			if (new_cap == NULL)
 546				return -ENOMEM;
 547			goto retry;
 548		}
 549
 550		cap->issued = 0;
 551		cap->implemented = 0;
 552		cap->mds = mds;
 553		cap->mds_wanted = 0;
 
 554
 555		cap->ci = ci;
 556		__insert_cap_node(ci, cap);
 557
 558		/* clear out old exporting info?  (i.e. on cap import) */
 559		if (ci->i_cap_exporting_mds == mds) {
 560			ci->i_cap_exporting_issued = 0;
 561			ci->i_cap_exporting_mseq = 0;
 562			ci->i_cap_exporting_mds = -1;
 563		}
 564
 565		/* add to session cap list */
 566		cap->session = session;
 567		spin_lock(&session->s_cap_lock);
 568		list_add_tail(&cap->session_caps, &session->s_caps);
 569		session->s_nr_caps++;
 570		spin_unlock(&session->s_cap_lock);
 571	} else if (new_cap)
 572		ceph_put_cap(mdsc, new_cap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 573
 574	if (!ci->i_snap_realm) {
 
 
 575		/*
 576		 * add this inode to the appropriate snap realm
 577		 */
 578		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 579							       realmino);
 580		if (realm) {
 581			ceph_get_snap_realm(mdsc, realm);
 
 
 
 
 
 
 582			spin_lock(&realm->inodes_with_caps_lock);
 583			ci->i_snap_realm = realm;
 584			list_add(&ci->i_snap_realm_item,
 585				 &realm->inodes_with_caps);
 
 
 
 586			spin_unlock(&realm->inodes_with_caps_lock);
 
 
 
 587		} else {
 588			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 589			       realmino);
 590			WARN_ON(!realm);
 591		}
 592	}
 593
 594	__check_cap_issue(ci, cap, issued);
 595
 596	/*
 597	 * If we are issued caps we don't want, or the mds' wanted
 598	 * value appears to be off, queue a check so we'll release
 599	 * later and/or update the mds wanted value.
 600	 */
 601	actual_wanted = __ceph_caps_wanted(ci);
 602	if ((wanted & ~actual_wanted) ||
 603	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 604		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 605		     ceph_cap_string(issued), ceph_cap_string(wanted),
 606		     ceph_cap_string(actual_wanted));
 607		__cap_delay_requeue(mdsc, ci);
 608	}
 609
 610	if (flags & CEPH_CAP_FLAG_AUTH)
 611		ci->i_auth_cap = cap;
 612	else if (ci->i_auth_cap == cap)
 613		ci->i_auth_cap = NULL;
 
 
 
 
 
 614
 615	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 616	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 617	     ceph_cap_string(issued|cap->issued), seq, mds);
 618	cap->cap_id = cap_id;
 619	cap->issued = issued;
 620	cap->implemented |= issued;
 621	cap->mds_wanted |= wanted;
 
 
 
 622	cap->seq = seq;
 623	cap->issue_seq = seq;
 624	cap->mseq = mseq;
 625	cap->cap_gen = session->s_cap_gen;
 626
 627	if (fmode >= 0)
 628		__ceph_get_fmode(ci, fmode);
 629	spin_unlock(&ci->i_ceph_lock);
 630	wake_up_all(&ci->i_cap_wq);
 631	return 0;
 632}
 633
 634/*
 635 * Return true if cap has not timed out and belongs to the current
 636 * generation of the MDS session (i.e. has not gone 'stale' due to
 637 * us losing touch with the mds).
 638 */
 639static int __cap_is_valid(struct ceph_cap *cap)
 640{
 641	unsigned long ttl;
 642	u32 gen;
 643
 644	spin_lock(&cap->session->s_gen_ttl_lock);
 645	gen = cap->session->s_cap_gen;
 646	ttl = cap->session->s_cap_ttl;
 647	spin_unlock(&cap->session->s_gen_ttl_lock);
 648
 649	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 650		dout("__cap_is_valid %p cap %p issued %s "
 651		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 652		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 653		return 0;
 654	}
 655
 656	return 1;
 657}
 658
 659/*
 660 * Return set of valid cap bits issued to us.  Note that caps time
 661 * out, and may be invalidated in bulk if the client session times out
 662 * and session->s_cap_gen is bumped.
 663 */
 664int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 665{
 666	int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
 667	struct ceph_cap *cap;
 668	struct rb_node *p;
 669
 670	if (implemented)
 671		*implemented = 0;
 672	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 673		cap = rb_entry(p, struct ceph_cap, ci_node);
 674		if (!__cap_is_valid(cap))
 675			continue;
 676		dout("__ceph_caps_issued %p cap %p issued %s\n",
 677		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 678		have |= cap->issued;
 679		if (implemented)
 680			*implemented |= cap->implemented;
 681	}
 
 
 
 
 
 
 
 
 
 682	return have;
 683}
 684
 685/*
 686 * Get cap bits issued by caps other than @ocap
 687 */
 688int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 689{
 690	int have = ci->i_snap_caps;
 691	struct ceph_cap *cap;
 692	struct rb_node *p;
 693
 694	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 695		cap = rb_entry(p, struct ceph_cap, ci_node);
 696		if (cap == ocap)
 697			continue;
 698		if (!__cap_is_valid(cap))
 699			continue;
 700		have |= cap->issued;
 701	}
 702	return have;
 703}
 704
 705/*
 706 * Move a cap to the end of the LRU (oldest caps at list head, newest
 707 * at list tail).
 708 */
 709static void __touch_cap(struct ceph_cap *cap)
 710{
 711	struct ceph_mds_session *s = cap->session;
 712
 713	spin_lock(&s->s_cap_lock);
 714	if (s->s_cap_iterator == NULL) {
 715		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 716		     s->s_mds);
 717		list_move_tail(&cap->session_caps, &s->s_caps);
 718	} else {
 719		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 720		     &cap->ci->vfs_inode, cap, s->s_mds);
 721	}
 722	spin_unlock(&s->s_cap_lock);
 723}
 724
 725/*
 726 * Check if we hold the given mask.  If so, move the cap(s) to the
 727 * front of their respective LRUs.  (This is the preferred way for
 728 * callers to check for caps they want.)
 729 */
 730int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 731{
 732	struct ceph_cap *cap;
 733	struct rb_node *p;
 734	int have = ci->i_snap_caps;
 735
 736	if ((have & mask) == mask) {
 737		dout("__ceph_caps_issued_mask %p snap issued %s"
 738		     " (mask %s)\n", &ci->vfs_inode,
 739		     ceph_cap_string(have),
 740		     ceph_cap_string(mask));
 741		return 1;
 742	}
 743
 744	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 745		cap = rb_entry(p, struct ceph_cap, ci_node);
 746		if (!__cap_is_valid(cap))
 747			continue;
 748		if ((cap->issued & mask) == mask) {
 749			dout("__ceph_caps_issued_mask %p cap %p issued %s"
 750			     " (mask %s)\n", &ci->vfs_inode, cap,
 751			     ceph_cap_string(cap->issued),
 752			     ceph_cap_string(mask));
 753			if (touch)
 754				__touch_cap(cap);
 755			return 1;
 756		}
 757
 758		/* does a combination of caps satisfy mask? */
 759		have |= cap->issued;
 760		if ((have & mask) == mask) {
 761			dout("__ceph_caps_issued_mask %p combo issued %s"
 762			     " (mask %s)\n", &ci->vfs_inode,
 763			     ceph_cap_string(cap->issued),
 764			     ceph_cap_string(mask));
 765			if (touch) {
 766				struct rb_node *q;
 767
 768				/* touch this + preceding caps */
 769				__touch_cap(cap);
 770				for (q = rb_first(&ci->i_caps); q != p;
 771				     q = rb_next(q)) {
 772					cap = rb_entry(q, struct ceph_cap,
 773						       ci_node);
 774					if (!__cap_is_valid(cap))
 775						continue;
 776					__touch_cap(cap);
 777				}
 778			}
 779			return 1;
 780		}
 781	}
 782
 783	return 0;
 784}
 785
 786/*
 787 * Return true if mask caps are currently being revoked by an MDS.
 788 */
 789int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 
 790{
 791	struct inode *inode = &ci->vfs_inode;
 792	struct ceph_cap *cap;
 793	struct rb_node *p;
 794	int ret = 0;
 795
 796	spin_lock(&ci->i_ceph_lock);
 797	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 798		cap = rb_entry(p, struct ceph_cap, ci_node);
 799		if (__cap_is_valid(cap) &&
 800		    (cap->implemented & ~cap->issued & mask)) {
 801			ret = 1;
 802			break;
 803		}
 804	}
 
 
 
 
 
 
 
 
 
 
 805	spin_unlock(&ci->i_ceph_lock);
 806	dout("ceph_caps_revoking %p %s = %d\n", inode,
 807	     ceph_cap_string(mask), ret);
 808	return ret;
 809}
 810
 811int __ceph_caps_used(struct ceph_inode_info *ci)
 812{
 813	int used = 0;
 814	if (ci->i_pin_ref)
 815		used |= CEPH_CAP_PIN;
 816	if (ci->i_rd_ref)
 817		used |= CEPH_CAP_FILE_RD;
 818	if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
 
 
 819		used |= CEPH_CAP_FILE_CACHE;
 820	if (ci->i_wr_ref)
 821		used |= CEPH_CAP_FILE_WR;
 822	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 823		used |= CEPH_CAP_FILE_BUFFER;
 824	return used;
 825}
 826
 827/*
 828 * wanted, by virtue of open file modes
 829 */
 830int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 831{
 832	int want = 0;
 833	int mode;
 834	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
 835		if (ci->i_nr_by_mode[mode])
 836			want |= ceph_caps_for_mode(mode);
 837	return want;
 
 
 838}
 839
 840/*
 841 * Return caps we have registered with the MDS(s) as 'wanted'.
 842 */
 843int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
 844{
 845	struct ceph_cap *cap;
 846	struct rb_node *p;
 847	int mds_wanted = 0;
 848
 849	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 850		cap = rb_entry(p, struct ceph_cap, ci_node);
 851		if (!__cap_is_valid(cap))
 852			continue;
 853		mds_wanted |= cap->mds_wanted;
 
 
 
 854	}
 855	return mds_wanted;
 856}
 857
 858/*
 859 * called under i_ceph_lock
 860 */
 
 
 
 
 
 861static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 862{
 863	return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_mds >= 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 864}
 865
 866/*
 867 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
 868 *
 869 * caller should hold i_ceph_lock.
 870 * caller will not hold session s_mutex if called from destroy_inode.
 871 */
 872void __ceph_remove_cap(struct ceph_cap *cap)
 873{
 874	struct ceph_mds_session *session = cap->session;
 875	struct ceph_inode_info *ci = cap->ci;
 876	struct ceph_mds_client *mdsc =
 877		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
 878	int removed = 0;
 879
 880	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
 881
 882	/* remove from session list */
 883	spin_lock(&session->s_cap_lock);
 884	if (session->s_cap_iterator == cap) {
 885		/* not yet, we are iterating over this very cap */
 886		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
 887		     cap, cap->session);
 888	} else {
 889		list_del_init(&cap->session_caps);
 890		session->s_nr_caps--;
 891		cap->session = NULL;
 892		removed = 1;
 893	}
 894	/* protect backpointer with s_cap_lock: see iterate_session_caps */
 895	cap->ci = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 896	spin_unlock(&session->s_cap_lock);
 897
 898	/* remove from inode list */
 899	rb_erase(&cap->ci_node, &ci->i_caps);
 900	if (ci->i_auth_cap == cap)
 901		ci->i_auth_cap = NULL;
 902
 903	if (removed)
 904		ceph_put_cap(mdsc, cap);
 905
 906	if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
 907		struct ceph_snap_realm *realm = ci->i_snap_realm;
 908		spin_lock(&realm->inodes_with_caps_lock);
 909		list_del_init(&ci->i_snap_realm_item);
 910		ci->i_snap_realm_counter++;
 911		ci->i_snap_realm = NULL;
 912		spin_unlock(&realm->inodes_with_caps_lock);
 913		ceph_put_snap_realm(mdsc, realm);
 914	}
 915	if (!__ceph_is_any_real_caps(ci))
 916		__cap_delay_cancel(mdsc, ci);
 917}
 918
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 919/*
 920 * Build and send a cap message to the given MDS.
 921 *
 922 * Caller should be holding s_mutex.
 923 */
 924static int send_cap_msg(struct ceph_mds_session *session,
 925			u64 ino, u64 cid, int op,
 926			int caps, int wanted, int dirty,
 927			u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
 928			u64 size, u64 max_size,
 929			struct timespec *mtime, struct timespec *atime,
 930			u64 time_warp_seq,
 931			uid_t uid, gid_t gid, umode_t mode,
 932			u64 xattr_version,
 933			struct ceph_buffer *xattrs_buf,
 934			u64 follows)
 935{
 936	struct ceph_mds_caps *fc;
 937	struct ceph_msg *msg;
 
 
 
 
 938
 939	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
 940	     " seq %u/%u mseq %u follows %lld size %llu/%llu"
 941	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
 942	     cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
 943	     ceph_cap_string(dirty),
 944	     seq, issue_seq, mseq, follows, size, max_size,
 945	     xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);
 946
 947	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc), GFP_NOFS, false);
 
 
 
 
 
 
 948	if (!msg)
 949		return -ENOMEM;
 950
 951	msg->hdr.tid = cpu_to_le64(flush_tid);
 
 952
 953	fc = msg->front.iov_base;
 954	memset(fc, 0, sizeof(*fc));
 955
 956	fc->cap_id = cpu_to_le64(cid);
 957	fc->op = cpu_to_le32(op);
 958	fc->seq = cpu_to_le32(seq);
 959	fc->issue_seq = cpu_to_le32(issue_seq);
 960	fc->migrate_seq = cpu_to_le32(mseq);
 961	fc->caps = cpu_to_le32(caps);
 962	fc->wanted = cpu_to_le32(wanted);
 963	fc->dirty = cpu_to_le32(dirty);
 964	fc->ino = cpu_to_le64(ino);
 965	fc->snap_follows = cpu_to_le64(follows);
 966
 967	fc->size = cpu_to_le64(size);
 968	fc->max_size = cpu_to_le64(max_size);
 969	if (mtime)
 970		ceph_encode_timespec(&fc->mtime, mtime);
 971	if (atime)
 972		ceph_encode_timespec(&fc->atime, atime);
 973	fc->time_warp_seq = cpu_to_le32(time_warp_seq);
 974
 975	fc->uid = cpu_to_le32(uid);
 976	fc->gid = cpu_to_le32(gid);
 977	fc->mode = cpu_to_le32(mode);
 978
 979	fc->xattr_version = cpu_to_le64(xattr_version);
 980	if (xattrs_buf) {
 981		msg->middle = ceph_buffer_get(xattrs_buf);
 982		fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
 983		msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
 984	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 985
 986	ceph_con_send(&session->s_con, msg);
 987	return 0;
 988}
 
 
 
 
 
 
 989
 990static void __queue_cap_release(struct ceph_mds_session *session,
 991				u64 ino, u64 cap_id, u32 migrate_seq,
 992				u32 issue_seq)
 993{
 994	struct ceph_msg *msg;
 995	struct ceph_mds_cap_release *head;
 996	struct ceph_mds_cap_item *item;
 997
 998	spin_lock(&session->s_cap_lock);
 999	BUG_ON(!session->s_num_cap_releases);
1000	msg = list_first_entry(&session->s_cap_releases,
1001			       struct ceph_msg, list_head);
1002
1003	dout(" adding %llx release to mds%d msg %p (%d left)\n",
1004	     ino, session->s_mds, msg, session->s_num_cap_releases);
1005
1006	BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
1007	head = msg->front.iov_base;
1008	head->num = cpu_to_le32(le32_to_cpu(head->num) + 1);
1009	item = msg->front.iov_base + msg->front.iov_len;
1010	item->ino = cpu_to_le64(ino);
1011	item->cap_id = cpu_to_le64(cap_id);
1012	item->migrate_seq = cpu_to_le32(migrate_seq);
1013	item->seq = cpu_to_le32(issue_seq);
1014
1015	session->s_num_cap_releases--;
1016
1017	msg->front.iov_len += sizeof(*item);
1018	if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
1019		dout(" release msg %p full\n", msg);
1020		list_move_tail(&msg->list_head, &session->s_cap_releases_done);
1021	} else {
1022		dout(" release msg %p at %d/%d (%d)\n", msg,
1023		     (int)le32_to_cpu(head->num),
1024		     (int)CEPH_CAPS_PER_RELEASE,
1025		     (int)msg->front.iov_len);
1026	}
1027	spin_unlock(&session->s_cap_lock);
1028}
1029
1030/*
1031 * Queue cap releases when an inode is dropped from our cache.  Since
1032 * inode is about to be destroyed, there is no need for i_ceph_lock.
1033 */
1034void ceph_queue_caps_release(struct inode *inode)
1035{
1036	struct ceph_inode_info *ci = ceph_inode(inode);
1037	struct rb_node *p;
1038
1039	p = rb_first(&ci->i_caps);
1040	while (p) {
1041		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1042		struct ceph_mds_session *session = cap->session;
1043
1044		__queue_cap_release(session, ceph_ino(inode), cap->cap_id,
1045				    cap->mseq, cap->issue_seq);
1046		p = rb_next(p);
1047		__ceph_remove_cap(cap);
1048	}
1049}
1050
1051/*
1052 * Send a cap msg on the given inode.  Update our caps state, then
1053 * drop i_ceph_lock and send the message.
1054 *
1055 * Make note of max_size reported/requested from mds, revoked caps
1056 * that have now been implemented.
1057 *
1058 * Make half-hearted attempt ot to invalidate page cache if we are
1059 * dropping RDCACHE.  Note that this will leave behind locked pages
1060 * that we'll then need to deal with elsewhere.
1061 *
1062 * Return non-zero if delayed release, or we experienced an error
1063 * such that the caller should requeue + retry later.
1064 *
1065 * called with i_ceph_lock, then drops it.
1066 * caller should hold snap_rwsem (read), s_mutex.
1067 */
1068static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1069		      int op, int used, int want, int retain, int flushing,
1070		      unsigned *pflush_tid)
1071	__releases(cap->ci->i_ceph_lock)
1072{
1073	struct ceph_inode_info *ci = cap->ci;
1074	struct inode *inode = &ci->vfs_inode;
1075	u64 cap_id = cap->cap_id;
1076	int held, revoking, dropping, keep;
1077	u64 seq, issue_seq, mseq, time_warp_seq, follows;
1078	u64 size, max_size;
1079	struct timespec mtime, atime;
1080	int wake = 0;
1081	umode_t mode;
1082	uid_t uid;
1083	gid_t gid;
1084	struct ceph_mds_session *session;
1085	u64 xattr_version = 0;
1086	struct ceph_buffer *xattr_blob = NULL;
1087	int delayed = 0;
1088	u64 flush_tid = 0;
1089	int i;
1090	int ret;
1091
1092	held = cap->issued | cap->implemented;
1093	revoking = cap->implemented & ~cap->issued;
1094	retain &= ~revoking;
1095	dropping = cap->issued & ~retain;
1096
1097	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1098	     inode, cap, cap->session,
1099	     ceph_cap_string(held), ceph_cap_string(held & retain),
1100	     ceph_cap_string(revoking));
1101	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1102
1103	session = cap->session;
1104
1105	/* don't release wanted unless we've waited a bit. */
1106	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1107	    time_before(jiffies, ci->i_hold_caps_min)) {
1108		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1109		     ceph_cap_string(cap->issued),
1110		     ceph_cap_string(cap->issued & retain),
1111		     ceph_cap_string(cap->mds_wanted),
1112		     ceph_cap_string(want));
1113		want |= cap->mds_wanted;
1114		retain |= cap->issued;
1115		delayed = 1;
1116	}
1117	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
 
 
 
 
 
 
 
1118
1119	cap->issued &= retain;  /* drop bits we don't want */
1120	if (cap->implemented & ~cap->issued) {
1121		/*
1122		 * Wake up any waiters on wanted -> needed transition.
1123		 * This is due to the weird transition from buffered
1124		 * to sync IO... we need to flush dirty pages _before_
1125		 * allowing sync writes to avoid reordering.
1126		 */
1127		wake = 1;
1128	}
1129	cap->implemented &= cap->issued | used;
1130	cap->mds_wanted = want;
1131
1132	if (flushing) {
1133		/*
1134		 * assign a tid for flush operations so we can avoid
1135		 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
1136		 * clean type races.  track latest tid for every bit
1137		 * so we can handle flush AxFw, flush Fw, and have the
1138		 * first ack clean Ax.
1139		 */
1140		flush_tid = ++ci->i_cap_flush_last_tid;
1141		if (pflush_tid)
1142			*pflush_tid = flush_tid;
1143		dout(" cap_flush_tid %d\n", (int)flush_tid);
1144		for (i = 0; i < CEPH_CAP_BITS; i++)
1145			if (flushing & (1 << i))
1146				ci->i_cap_flush_tid[i] = flush_tid;
1147
1148		follows = ci->i_head_snapc->seq;
 
 
 
1149	} else {
1150		follows = 0;
1151	}
1152
1153	keep = cap->implemented;
1154	seq = cap->seq;
1155	issue_seq = cap->issue_seq;
1156	mseq = cap->mseq;
1157	size = inode->i_size;
1158	ci->i_reported_size = size;
1159	max_size = ci->i_wanted_max_size;
1160	ci->i_requested_max_size = max_size;
1161	mtime = inode->i_mtime;
1162	atime = inode->i_atime;
1163	time_warp_seq = ci->i_time_warp_seq;
1164	uid = inode->i_uid;
1165	gid = inode->i_gid;
1166	mode = inode->i_mode;
1167
1168	if (flushing & CEPH_CAP_XATTR_EXCL) {
1169		__ceph_build_xattrs_blob(ci);
1170		xattr_blob = ci->i_xattrs.blob;
1171		xattr_version = ci->i_xattrs.version;
1172	}
 
 
 
 
 
1173
1174	spin_unlock(&ci->i_ceph_lock);
1175
1176	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
1177		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
1178		size, max_size, &mtime, &atime, time_warp_seq,
1179		uid, gid, mode, xattr_version, xattr_blob,
1180		follows);
1181	if (ret < 0) {
1182		dout("error sending cap msg, must requeue %p\n", inode);
1183		delayed = 1;
1184	}
1185
1186	if (wake)
1187		wake_up_all(&ci->i_cap_wq);
1188
1189	return delayed;
1190}
1191
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1192/*
1193 * When a snapshot is taken, clients accumulate dirty metadata on
1194 * inodes with capabilities in ceph_cap_snaps to describe the file
1195 * state at the time the snapshot was taken.  This must be flushed
1196 * asynchronously back to the MDS once sync writes complete and dirty
1197 * data is written out.
1198 *
1199 * Unless @again is true, skip cap_snaps that were already sent to
1200 * the MDS (i.e., during this session).
1201 *
1202 * Called under i_ceph_lock.  Takes s_mutex as needed.
1203 */
1204void __ceph_flush_snaps(struct ceph_inode_info *ci,
1205			struct ceph_mds_session **psession,
1206			int again)
1207		__releases(ci->i_ceph_lock)
1208		__acquires(ci->i_ceph_lock)
1209{
1210	struct inode *inode = &ci->vfs_inode;
1211	int mds;
1212	struct ceph_cap_snap *capsnap;
1213	u32 mseq;
1214	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1215	struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
1216						    session->s_mutex */
1217	u64 next_follows = 0;  /* keep track of how far we've gotten through the
1218			     i_cap_snaps list, and skip these entries next time
1219			     around to avoid an infinite loop */
1220
1221	if (psession)
1222		session = *psession;
1223
1224	dout("__flush_snaps %p\n", inode);
1225retry:
1226	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1227		/* avoid an infiniute loop after retry */
1228		if (capsnap->follows < next_follows)
1229			continue;
1230		/*
1231		 * we need to wait for sync writes to complete and for dirty
1232		 * pages to be written out.
1233		 */
1234		if (capsnap->dirty_pages || capsnap->writing)
1235			break;
1236
1237		/*
1238		 * if cap writeback already occurred, we should have dropped
1239		 * the capsnap in ceph_put_wrbuffer_cap_refs.
1240		 */
1241		BUG_ON(capsnap->dirty == 0);
1242
1243		/* pick mds, take s_mutex */
1244		if (ci->i_auth_cap == NULL) {
1245			dout("no auth cap (migrating?), doing nothing\n");
1246			goto out;
1247		}
1248
1249		/* only flush each capsnap once */
1250		if (!again && !list_empty(&capsnap->flushing_item)) {
1251			dout("already flushed %p, skipping\n", capsnap);
1252			continue;
1253		}
1254
1255		mds = ci->i_auth_cap->session->s_mds;
1256		mseq = ci->i_auth_cap->mseq;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1257
1258		if (session && session->s_mds != mds) {
1259			dout("oops, wrong session %p mutex\n", session);
1260			mutex_unlock(&session->s_mutex);
1261			ceph_put_mds_session(session);
1262			session = NULL;
1263		}
1264		if (!session) {
1265			spin_unlock(&ci->i_ceph_lock);
1266			mutex_lock(&mdsc->mutex);
1267			session = __ceph_lookup_mds_session(mdsc, mds);
1268			mutex_unlock(&mdsc->mutex);
1269			if (session) {
1270				dout("inverting session/ino locks on %p\n",
1271				     session);
1272				mutex_lock(&session->s_mutex);
1273			}
1274			/*
1275			 * if session == NULL, we raced against a cap
1276			 * deletion or migration.  retry, and we'll
1277			 * get a better @mds value next time.
1278			 */
1279			spin_lock(&ci->i_ceph_lock);
1280			goto retry;
1281		}
 
 
1282
1283		capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
1284		atomic_inc(&capsnap->nref);
1285		if (!list_empty(&capsnap->flushing_item))
1286			list_del_init(&capsnap->flushing_item);
1287		list_add_tail(&capsnap->flushing_item,
1288			      &session->s_cap_snaps_flushing);
1289		spin_unlock(&ci->i_ceph_lock);
1290
1291		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
1292		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
1293		send_cap_msg(session, ceph_vino(inode).ino, 0,
1294			     CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
1295			     capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
1296			     capsnap->size, 0,
1297			     &capsnap->mtime, &capsnap->atime,
1298			     capsnap->time_warp_seq,
1299			     capsnap->uid, capsnap->gid, capsnap->mode,
1300			     capsnap->xattr_version, capsnap->xattr_blob,
1301			     capsnap->follows);
1302
1303		next_follows = capsnap->follows + 1;
1304		ceph_put_cap_snap(capsnap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1305
1306		spin_lock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1307		goto retry;
1308	}
1309
1310	/* we flushed them all; remove this inode from the queue */
1311	spin_lock(&mdsc->snap_flush_lock);
1312	list_del_init(&ci->i_snap_flush_item);
1313	spin_unlock(&mdsc->snap_flush_lock);
 
1314
 
1315out:
1316	if (psession)
 
 
1317		*psession = session;
1318	else if (session) {
1319		mutex_unlock(&session->s_mutex);
1320		ceph_put_mds_session(session);
1321	}
1322}
1323
1324static void ceph_flush_snaps(struct ceph_inode_info *ci)
1325{
1326	spin_lock(&ci->i_ceph_lock);
1327	__ceph_flush_snaps(ci, NULL, 0);
1328	spin_unlock(&ci->i_ceph_lock);
1329}
1330
1331/*
1332 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1333 * Caller is then responsible for calling __mark_inode_dirty with the
1334 * returned flags value.
1335 */
1336int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
 
1337{
1338	struct ceph_mds_client *mdsc =
1339		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1340	struct inode *inode = &ci->vfs_inode;
1341	int was = ci->i_dirty_caps;
1342	int dirty = 0;
1343
 
 
 
 
 
 
 
1344	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1345	     ceph_cap_string(mask), ceph_cap_string(was),
1346	     ceph_cap_string(was | mask));
1347	ci->i_dirty_caps |= mask;
1348	if (was == 0) {
1349		if (!ci->i_head_snapc)
 
 
 
 
1350			ci->i_head_snapc = ceph_get_snap_context(
1351				ci->i_snap_realm->cached_context);
1352		dout(" inode %p now dirty snapc %p\n", &ci->vfs_inode,
1353			ci->i_head_snapc);
 
1354		BUG_ON(!list_empty(&ci->i_dirty_item));
1355		spin_lock(&mdsc->cap_dirty_lock);
1356		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1357		spin_unlock(&mdsc->cap_dirty_lock);
1358		if (ci->i_flushing_caps == 0) {
1359			ihold(inode);
1360			dirty |= I_DIRTY_SYNC;
1361		}
 
 
1362	}
1363	BUG_ON(list_empty(&ci->i_dirty_item));
1364	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1365	    (mask & CEPH_CAP_FILE_BUFFER))
1366		dirty |= I_DIRTY_DATASYNC;
1367	__cap_delay_requeue(mdsc, ci);
1368	return dirty;
1369}
1370
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1371/*
1372 * Add dirty inode to the flushing list.  Assigned a seq number so we
1373 * can wait for caps to flush without starving.
1374 *
1375 * Called under i_ceph_lock.
1376 */
1377static int __mark_caps_flushing(struct inode *inode,
1378				 struct ceph_mds_session *session)
 
1379{
1380	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1381	struct ceph_inode_info *ci = ceph_inode(inode);
 
1382	int flushing;
1383
1384	BUG_ON(ci->i_dirty_caps == 0);
1385	BUG_ON(list_empty(&ci->i_dirty_item));
 
1386
1387	flushing = ci->i_dirty_caps;
1388	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1389	     ceph_cap_string(flushing),
1390	     ceph_cap_string(ci->i_flushing_caps),
1391	     ceph_cap_string(ci->i_flushing_caps | flushing));
1392	ci->i_flushing_caps |= flushing;
1393	ci->i_dirty_caps = 0;
1394	dout(" inode %p now !dirty\n", inode);
1395
 
 
 
 
1396	spin_lock(&mdsc->cap_dirty_lock);
1397	list_del_init(&ci->i_dirty_item);
1398
1399	ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
 
 
 
1400	if (list_empty(&ci->i_flushing_item)) {
1401		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1402		mdsc->num_cap_flushing++;
1403		dout(" inode %p now flushing seq %lld\n", inode,
1404		     ci->i_cap_flush_seq);
1405	} else {
1406		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1407		dout(" inode %p now flushing (more) seq %lld\n", inode,
1408		     ci->i_cap_flush_seq);
1409	}
1410	spin_unlock(&mdsc->cap_dirty_lock);
1411
 
 
 
1412	return flushing;
1413}
1414
1415/*
1416 * try to invalidate mapping pages without blocking.
1417 */
1418static int try_nonblocking_invalidate(struct inode *inode)
1419{
1420	struct ceph_inode_info *ci = ceph_inode(inode);
1421	u32 invalidating_gen = ci->i_rdcache_gen;
1422
1423	spin_unlock(&ci->i_ceph_lock);
1424	invalidate_mapping_pages(&inode->i_data, 0, -1);
1425	spin_lock(&ci->i_ceph_lock);
1426
1427	if (inode->i_data.nrpages == 0 &&
1428	    invalidating_gen == ci->i_rdcache_gen) {
1429		/* success. */
1430		dout("try_nonblocking_invalidate %p success\n", inode);
1431		/* save any racing async invalidate some trouble */
1432		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1433		return 0;
1434	}
1435	dout("try_nonblocking_invalidate %p failed\n", inode);
1436	return -1;
1437}
1438
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1439/*
1440 * Swiss army knife function to examine currently used and wanted
1441 * versus held caps.  Release, flush, ack revoked caps to mds as
1442 * appropriate.
1443 *
1444 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1445 *    cap release further.
1446 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1447 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1448 *    further delay.
1449 */
1450void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1451		     struct ceph_mds_session *session)
1452{
1453	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1454	struct ceph_mds_client *mdsc = fsc->mdsc;
1455	struct inode *inode = &ci->vfs_inode;
1456	struct ceph_cap *cap;
1457	int file_wanted, used;
 
1458	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1459	int issued, implemented, want, retain, revoking, flushing = 0;
1460	int mds = -1;   /* keep track of how far we've gone through i_caps list
1461			   to avoid an infinite loop on retry */
1462	struct rb_node *p;
1463	int tried_invalidate = 0;
1464	int delayed = 0, sent = 0, force_requeue = 0, num;
1465	int queue_invalidate = 0;
1466	int is_delayed = flags & CHECK_CAPS_NODELAY;
1467
1468	/* if we are unmounting, flush any unused caps immediately. */
1469	if (mdsc->stopping)
1470		is_delayed = 1;
1471
1472	spin_lock(&ci->i_ceph_lock);
1473
1474	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1475		flags |= CHECK_CAPS_FLUSH;
1476
1477	/* flush snaps first time around only */
1478	if (!list_empty(&ci->i_cap_snaps))
1479		__ceph_flush_snaps(ci, &session, 0);
 
1480	goto retry_locked;
1481retry:
1482	spin_lock(&ci->i_ceph_lock);
1483retry_locked:
1484	file_wanted = __ceph_caps_file_wanted(ci);
1485	used = __ceph_caps_used(ci);
1486	want = file_wanted | used;
1487	issued = __ceph_caps_issued(ci, &implemented);
1488	revoking = implemented & ~issued;
1489
1490	retain = want | CEPH_CAP_PIN;
 
1491	if (!mdsc->stopping && inode->i_nlink > 0) {
1492		if (want) {
1493			retain |= CEPH_CAP_ANY;       /* be greedy */
 
 
 
 
 
 
 
 
 
 
 
1494		} else {
 
1495			retain |= CEPH_CAP_ANY_SHARED;
1496			/*
1497			 * keep RD only if we didn't have the file open RW,
1498			 * because then the mds would revoke it anyway to
1499			 * journal max_size=0.
1500			 */
1501			if (ci->i_max_size == 0)
1502				retain |= CEPH_CAP_ANY_RD;
1503		}
1504	}
1505
1506	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1507	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1508	     ceph_cap_string(file_wanted),
1509	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1510	     ceph_cap_string(ci->i_flushing_caps),
1511	     ceph_cap_string(issued), ceph_cap_string(revoking),
1512	     ceph_cap_string(retain),
1513	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1514	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1515	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1516
1517	/*
1518	 * If we no longer need to hold onto old our caps, and we may
1519	 * have cached pages, but don't want them, then try to invalidate.
1520	 * If we fail, it's because pages are locked.... try again later.
1521	 */
1522	if ((!is_delayed || mdsc->stopping) &&
1523	    ci->i_wrbuffer_ref == 0 &&               /* no dirty pages... */
1524	    inode->i_data.nrpages &&                 /* have cached pages */
1525	    (file_wanted == 0 ||                     /* no open files */
1526	     (revoking & (CEPH_CAP_FILE_CACHE|
1527			  CEPH_CAP_FILE_LAZYIO))) && /*  or revoking cache */
1528	    !tried_invalidate) {
1529		dout("check_caps trying to invalidate on %p\n", inode);
1530		if (try_nonblocking_invalidate(inode) < 0) {
1531			if (revoking & (CEPH_CAP_FILE_CACHE|
1532					CEPH_CAP_FILE_LAZYIO)) {
1533				dout("check_caps queuing invalidate\n");
1534				queue_invalidate = 1;
1535				ci->i_rdcache_revoking = ci->i_rdcache_gen;
1536			} else {
1537				dout("check_caps failed to invalidate pages\n");
1538				/* we failed to invalidate pages.  check these
1539				   caps again later. */
1540				force_requeue = 1;
1541				__cap_set_timeouts(mdsc, ci);
1542			}
1543		}
1544		tried_invalidate = 1;
1545		goto retry_locked;
1546	}
1547
1548	num = 0;
1549	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1550		cap = rb_entry(p, struct ceph_cap, ci_node);
1551		num++;
1552
1553		/* avoid looping forever */
1554		if (mds >= cap->mds ||
1555		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1556			continue;
1557
1558		/* NOTE: no side-effects allowed, until we take s_mutex */
1559
 
 
 
 
1560		revoking = cap->implemented & ~cap->issued;
1561		dout(" mds%d cap %p issued %s implemented %s revoking %s\n",
1562		     cap->mds, cap, ceph_cap_string(cap->issued),
 
1563		     ceph_cap_string(cap->implemented),
1564		     ceph_cap_string(revoking));
1565
1566		if (cap == ci->i_auth_cap &&
1567		    (cap->issued & CEPH_CAP_FILE_WR)) {
1568			/* request larger max_size from MDS? */
1569			if (ci->i_wanted_max_size > ci->i_max_size &&
1570			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1571				dout("requesting new max_size\n");
1572				goto ack;
1573			}
1574
1575			/* approaching file_max? */
1576			if ((inode->i_size << 1) >= ci->i_max_size &&
1577			    (ci->i_reported_size << 1) < ci->i_max_size) {
1578				dout("i_size approaching max_size\n");
1579				goto ack;
1580			}
1581		}
1582		/* flush anything dirty? */
1583		if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
1584		    ci->i_dirty_caps) {
1585			dout("flushing dirty caps\n");
1586			goto ack;
 
 
 
 
 
1587		}
1588
1589		/* completed revocation? going down and there are no caps? */
1590		if (revoking && (revoking & used) == 0) {
1591			dout("completed revocation of %s\n",
1592			     ceph_cap_string(cap->implemented & ~cap->issued));
1593			goto ack;
1594		}
1595
1596		/* want more caps from mds? */
1597		if (want & ~(cap->mds_wanted | cap->issued))
1598			goto ack;
1599
1600		/* things we might delay */
1601		if ((cap->issued & ~retain) == 0 &&
1602		    cap->mds_wanted == want)
1603			continue;     /* nope, all good */
1604
1605		if (is_delayed)
1606			goto ack;
1607
1608		/* delay? */
1609		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1610		    time_before(jiffies, ci->i_hold_caps_max)) {
1611			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1612			     ceph_cap_string(cap->issued),
1613			     ceph_cap_string(cap->issued & retain),
1614			     ceph_cap_string(cap->mds_wanted),
1615			     ceph_cap_string(want));
1616			delayed++;
1617			continue;
1618		}
1619
1620ack:
1621		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1622			dout(" skipping %p I_NOFLUSH set\n", inode);
1623			continue;
1624		}
1625
1626		if (session && session != cap->session) {
1627			dout("oops, wrong session %p mutex\n", session);
1628			mutex_unlock(&session->s_mutex);
1629			session = NULL;
1630		}
1631		if (!session) {
1632			session = cap->session;
1633			if (mutex_trylock(&session->s_mutex) == 0) {
1634				dout("inverting session/ino locks on %p\n",
1635				     session);
1636				spin_unlock(&ci->i_ceph_lock);
1637				if (took_snap_rwsem) {
1638					up_read(&mdsc->snap_rwsem);
1639					took_snap_rwsem = 0;
1640				}
1641				mutex_lock(&session->s_mutex);
1642				goto retry;
1643			}
1644		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1645		/* take snap_rwsem after session mutex */
1646		if (!took_snap_rwsem) {
1647			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1648				dout("inverting snap/in locks on %p\n",
1649				     inode);
1650				spin_unlock(&ci->i_ceph_lock);
1651				down_read(&mdsc->snap_rwsem);
1652				took_snap_rwsem = 1;
1653				goto retry;
1654			}
1655			took_snap_rwsem = 1;
1656		}
1657
1658		if (cap == ci->i_auth_cap && ci->i_dirty_caps)
1659			flushing = __mark_caps_flushing(inode, session);
1660		else
 
 
1661			flushing = 0;
 
 
 
 
 
1662
1663		mds = cap->mds;  /* remember mds, so we don't repeat */
1664		sent++;
1665
1666		/* __send_cap drops i_ceph_lock */
1667		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, used, want,
1668				      retain, flushing, NULL);
 
1669		goto retry; /* retake i_ceph_lock and restart our cap scan. */
1670	}
1671
1672	/*
1673	 * Reschedule delayed caps release if we delayed anything,
1674	 * otherwise cancel.
1675	 */
1676	if (delayed && is_delayed)
1677		force_requeue = 1;   /* __send_cap delayed release; requeue */
1678	if (!delayed && !is_delayed)
1679		__cap_delay_cancel(mdsc, ci);
1680	else if (!is_delayed || force_requeue)
1681		__cap_delay_requeue(mdsc, ci);
1682
1683	spin_unlock(&ci->i_ceph_lock);
1684
1685	if (queue_invalidate)
1686		ceph_queue_invalidate(inode);
1687
1688	if (session)
1689		mutex_unlock(&session->s_mutex);
1690	if (took_snap_rwsem)
1691		up_read(&mdsc->snap_rwsem);
1692}
1693
1694/*
1695 * Try to flush dirty caps back to the auth mds.
1696 */
1697static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
1698			  unsigned *flush_tid)
1699{
1700	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1701	struct ceph_inode_info *ci = ceph_inode(inode);
1702	int unlock_session = session ? 0 : 1;
1703	int flushing = 0;
 
1704
1705retry:
1706	spin_lock(&ci->i_ceph_lock);
1707	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
 
1708		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1709		goto out;
1710	}
1711	if (ci->i_dirty_caps && ci->i_auth_cap) {
1712		struct ceph_cap *cap = ci->i_auth_cap;
1713		int used = __ceph_caps_used(ci);
1714		int want = __ceph_caps_wanted(ci);
1715		int delayed;
1716
1717		if (!session) {
1718			spin_unlock(&ci->i_ceph_lock);
 
 
1719			session = cap->session;
1720			mutex_lock(&session->s_mutex);
1721			goto retry;
1722		}
1723		BUG_ON(session != cap->session);
1724		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
1725			goto out;
 
1726
1727		flushing = __mark_caps_flushing(inode, session);
 
1728
1729		/* __send_cap drops i_ceph_lock */
1730		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
1731				     cap->issued | cap->implemented, flushing,
1732				     flush_tid);
1733		if (!delayed)
1734			goto out_unlocked;
1735
1736		spin_lock(&ci->i_ceph_lock);
1737		__cap_delay_requeue(mdsc, ci);
 
 
 
 
 
 
 
 
 
 
 
 
 
1738	}
1739out:
1740	spin_unlock(&ci->i_ceph_lock);
1741out_unlocked:
1742	if (session && unlock_session)
1743		mutex_unlock(&session->s_mutex);
 
 
1744	return flushing;
1745}
1746
1747/*
1748 * Return true if we've flushed caps through the given flush_tid.
1749 */
1750static int caps_are_flushed(struct inode *inode, unsigned tid)
1751{
1752	struct ceph_inode_info *ci = ceph_inode(inode);
1753	int i, ret = 1;
1754
1755	spin_lock(&ci->i_ceph_lock);
1756	for (i = 0; i < CEPH_CAP_BITS; i++)
1757		if ((ci->i_flushing_caps & (1 << i)) &&
1758		    ci->i_cap_flush_tid[i] <= tid) {
1759			/* still flushing this bit */
 
1760			ret = 0;
1761			break;
1762		}
1763	spin_unlock(&ci->i_ceph_lock);
1764	return ret;
1765}
1766
1767/*
1768 * Wait on any unsafe replies for the given inode.  First wait on the
1769 * newest request, and make that the upper bound.  Then, if there are
1770 * more requests, keep waiting on the oldest as long as it is still older
1771 * than the original request.
1772 */
1773static void sync_write_wait(struct inode *inode)
1774{
1775	struct ceph_inode_info *ci = ceph_inode(inode);
1776	struct list_head *head = &ci->i_unsafe_writes;
1777	struct ceph_osd_request *req;
1778	u64 last_tid;
1779
1780	spin_lock(&ci->i_unsafe_lock);
1781	if (list_empty(head))
1782		goto out;
 
 
 
 
 
 
 
 
 
 
 
1783
1784	/* set upper bound as _last_ entry in chain */
1785	req = list_entry(head->prev, struct ceph_osd_request,
1786			 r_unsafe_item);
1787	last_tid = req->r_tid;
1788
1789	do {
1790		ceph_osdc_get_request(req);
1791		spin_unlock(&ci->i_unsafe_lock);
1792		dout("sync_write_wait on tid %llu (until %llu)\n",
1793		     req->r_tid, last_tid);
1794		wait_for_completion(&req->r_safe_completion);
1795		spin_lock(&ci->i_unsafe_lock);
1796		ceph_osdc_put_request(req);
1797
1798		/*
1799		 * from here on look at first entry in chain, since we
1800		 * only want to wait for anything older than last_tid
1801		 */
1802		if (list_empty(head))
1803			break;
1804		req = list_entry(head->next, struct ceph_osd_request,
1805				 r_unsafe_item);
1806	} while (req->r_tid < last_tid);
1807out:
1808	spin_unlock(&ci->i_unsafe_lock);
1809}
1810
1811int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
1812{
1813	struct inode *inode = file->f_mapping->host;
1814	struct ceph_inode_info *ci = ceph_inode(inode);
1815	unsigned flush_tid;
1816	int ret;
1817	int dirty;
1818
1819	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
1820	sync_write_wait(inode);
1821
1822	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1823	if (ret < 0)
1824		return ret;
1825	mutex_lock(&inode->i_mutex);
 
 
 
 
1826
1827	dirty = try_flush_caps(inode, NULL, &flush_tid);
1828	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
1829
 
 
1830	/*
1831	 * only wait on non-file metadata writeback (the mds
1832	 * can recover size and mtime, so we don't need to
1833	 * wait for that)
1834	 */
1835	if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
1836		dout("fsync waiting for flush_tid %u\n", flush_tid);
1837		ret = wait_event_interruptible(ci->i_cap_wq,
1838				       caps_are_flushed(inode, flush_tid));
1839	}
1840
1841	dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
1842	mutex_unlock(&inode->i_mutex);
1843	return ret;
1844}
1845
1846/*
1847 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
1848 * queue inode for flush but don't do so immediately, because we can
1849 * get by with fewer MDS messages if we wait for data writeback to
1850 * complete first.
1851 */
1852int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
1853{
1854	struct ceph_inode_info *ci = ceph_inode(inode);
1855	unsigned flush_tid;
1856	int err = 0;
1857	int dirty;
1858	int wait = wbc->sync_mode == WB_SYNC_ALL;
1859
1860	dout("write_inode %p wait=%d\n", inode, wait);
1861	if (wait) {
1862		dirty = try_flush_caps(inode, NULL, &flush_tid);
1863		if (dirty)
1864			err = wait_event_interruptible(ci->i_cap_wq,
1865				       caps_are_flushed(inode, flush_tid));
1866	} else {
1867		struct ceph_mds_client *mdsc =
1868			ceph_sb_to_client(inode->i_sb)->mdsc;
1869
1870		spin_lock(&ci->i_ceph_lock);
1871		if (__ceph_caps_dirty(ci))
1872			__cap_delay_requeue_front(mdsc, ci);
1873		spin_unlock(&ci->i_ceph_lock);
1874	}
1875	return err;
1876}
1877
1878/*
1879 * After a recovering MDS goes active, we need to resend any caps
1880 * we were flushing.
1881 *
1882 * Caller holds session->s_mutex.
1883 */
1884static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1885				   struct ceph_mds_session *session)
1886{
1887	struct ceph_cap_snap *capsnap;
 
 
 
 
1888
1889	dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
1890	list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
1891			    flushing_item) {
1892		struct ceph_inode_info *ci = capsnap->ci;
1893		struct inode *inode = &ci->vfs_inode;
1894		struct ceph_cap *cap;
1895
 
1896		spin_lock(&ci->i_ceph_lock);
1897		cap = ci->i_auth_cap;
1898		if (cap && cap->session == session) {
1899			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
1900			     cap, capsnap);
1901			__ceph_flush_snaps(ci, &session, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1902		} else {
1903			pr_err("%p auth cap %p not mds%d ???\n", inode,
1904			       cap, session->s_mds);
1905		}
 
1906		spin_unlock(&ci->i_ceph_lock);
1907	}
1908}
1909
1910void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
1911			     struct ceph_mds_session *session)
1912{
1913	struct ceph_inode_info *ci;
 
 
1914
1915	kick_flushing_capsnaps(mdsc, session);
 
 
 
 
1916
1917	dout("kick_flushing_caps mds%d\n", session->s_mds);
1918	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
1919		struct inode *inode = &ci->vfs_inode;
1920		struct ceph_cap *cap;
1921		int delayed = 0;
1922
1923		spin_lock(&ci->i_ceph_lock);
1924		cap = ci->i_auth_cap;
1925		if (cap && cap->session == session) {
1926			dout("kick_flushing_caps %p cap %p %s\n", inode,
1927			     cap, ceph_cap_string(ci->i_flushing_caps));
1928			delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1929					     __ceph_caps_used(ci),
1930					     __ceph_caps_wanted(ci),
1931					     cap->issued | cap->implemented,
1932					     ci->i_flushing_caps, NULL);
1933			if (delayed) {
1934				spin_lock(&ci->i_ceph_lock);
1935				__cap_delay_requeue(mdsc, ci);
1936				spin_unlock(&ci->i_ceph_lock);
1937			}
1938		} else {
1939			pr_err("%p auth cap %p not mds%d ???\n", inode,
1940			       cap, session->s_mds);
1941			spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
1942		}
 
1943	}
1944}
1945
1946static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
1947				     struct ceph_mds_session *session,
1948				     struct inode *inode)
 
1949{
1950	struct ceph_inode_info *ci = ceph_inode(inode);
1951	struct ceph_cap *cap;
1952	int delayed = 0;
1953
1954	spin_lock(&ci->i_ceph_lock);
1955	cap = ci->i_auth_cap;
1956	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
1957	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
1958	__ceph_flush_snaps(ci, &session, 1);
1959	if (ci->i_flushing_caps) {
1960		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1961				     __ceph_caps_used(ci),
1962				     __ceph_caps_wanted(ci),
1963				     cap->issued | cap->implemented,
1964				     ci->i_flushing_caps, NULL);
1965		if (delayed) {
1966			spin_lock(&ci->i_ceph_lock);
1967			__cap_delay_requeue(mdsc, ci);
1968			spin_unlock(&ci->i_ceph_lock);
1969		}
1970	} else {
1971		spin_unlock(&ci->i_ceph_lock);
1972	}
1973}
1974
1975
1976/*
1977 * Take references to capabilities we hold, so that we don't release
1978 * them to the MDS prematurely.
1979 *
1980 * Protected by i_ceph_lock.
1981 */
1982static void __take_cap_refs(struct ceph_inode_info *ci, int got)
 
1983{
1984	if (got & CEPH_CAP_PIN)
1985		ci->i_pin_ref++;
1986	if (got & CEPH_CAP_FILE_RD)
1987		ci->i_rd_ref++;
1988	if (got & CEPH_CAP_FILE_CACHE)
1989		ci->i_rdcache_ref++;
1990	if (got & CEPH_CAP_FILE_WR)
 
 
 
 
 
1991		ci->i_wr_ref++;
 
1992	if (got & CEPH_CAP_FILE_BUFFER) {
1993		if (ci->i_wb_ref == 0)
1994			ihold(&ci->vfs_inode);
1995		ci->i_wb_ref++;
1996		dout("__take_cap_refs %p wb %d -> %d (?)\n",
1997		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
1998	}
1999}
2000
2001/*
2002 * Try to grab cap references.  Specify those refs we @want, and the
2003 * minimal set we @need.  Also include the larger offset we are writing
2004 * to (when applicable), and check against max_size here as well.
2005 * Note that caller is responsible for ensuring max_size increases are
2006 * requested from the MDS.
2007 */
2008static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
2009			    int *got, loff_t endoff, int *check_max, int *err)
2010{
2011	struct inode *inode = &ci->vfs_inode;
 
2012	int ret = 0;
2013	int have, implemented;
2014	int file_wanted;
 
2015
2016	dout("get_cap_refs %p need %s want %s\n", inode,
2017	     ceph_cap_string(need), ceph_cap_string(want));
 
 
2018	spin_lock(&ci->i_ceph_lock);
2019
2020	/* make sure file is actually open */
2021	file_wanted = __ceph_caps_file_wanted(ci);
2022	if ((file_wanted & need) == 0) {
2023		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2024		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2025		*err = -EBADF;
2026		ret = 1;
2027		goto out;
 
 
 
 
 
 
 
 
 
 
 
2028	}
2029
2030	if (need & CEPH_CAP_FILE_WR) {
 
 
2031		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2032			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2033			     inode, endoff, ci->i_max_size);
2034			if (endoff > ci->i_wanted_max_size) {
2035				*check_max = 1;
2036				ret = 1;
2037			}
2038			goto out;
2039		}
2040		/*
2041		 * If a sync write is in progress, we must wait, so that we
2042		 * can get a final snapshot value for size+mtime.
2043		 */
2044		if (__ceph_have_pending_cap_snap(ci)) {
2045			dout("get_cap_refs %p cap_snap_pending\n", inode);
2046			goto out;
2047		}
2048	}
2049	have = __ceph_caps_issued(ci, &implemented);
2050
2051	/*
2052	 * disallow writes while a truncate is pending
2053	 */
2054	if (ci->i_truncate_pending)
2055		have &= ~CEPH_CAP_FILE_WR;
2056
2057	if ((have & need) == need) {
2058		/*
2059		 * Look at (implemented & ~have & not) so that we keep waiting
2060		 * on transition from wanted -> needed caps.  This is needed
2061		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2062		 * going before a prior buffered writeback happens.
2063		 */
2064		int not = want & ~(have & need);
2065		int revoking = implemented & ~have;
2066		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2067		     inode, ceph_cap_string(have), ceph_cap_string(not),
2068		     ceph_cap_string(revoking));
2069		if ((revoking & not) == 0) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2070			*got = need | (have & want);
2071			__take_cap_refs(ci, *got);
 
 
 
2072			ret = 1;
2073		}
2074	} else {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2075		dout("get_cap_refs %p have %s needed %s\n", inode,
2076		     ceph_cap_string(have), ceph_cap_string(need));
2077	}
2078out:
2079	spin_unlock(&ci->i_ceph_lock);
 
 
 
2080	dout("get_cap_refs %p ret %d got %s\n", inode,
2081	     ret, ceph_cap_string(*got));
2082	return ret;
2083}
2084
2085/*
2086 * Check the offset we are writing up to against our current
2087 * max_size.  If necessary, tell the MDS we want to write to
2088 * a larger offset.
2089 */
2090static void check_max_size(struct inode *inode, loff_t endoff)
2091{
2092	struct ceph_inode_info *ci = ceph_inode(inode);
2093	int check = 0;
2094
2095	/* do we need to explicitly request a larger max_size? */
2096	spin_lock(&ci->i_ceph_lock);
2097	if ((endoff >= ci->i_max_size ||
2098	     endoff > (inode->i_size << 1)) &&
2099	    endoff > ci->i_wanted_max_size) {
2100		dout("write %p at large endoff %llu, req max_size\n",
2101		     inode, endoff);
2102		ci->i_wanted_max_size = endoff;
 
 
 
 
 
 
2103		check = 1;
2104	}
2105	spin_unlock(&ci->i_ceph_lock);
2106	if (check)
2107		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2108}
2109
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2110/*
2111 * Wait for caps, and take cap references.  If we can't get a WR cap
2112 * due to a small max_size, make sure we check_max_size (and possibly
2113 * ask the mds) so we don't get hung up indefinitely.
2114 */
2115int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got,
2116		  loff_t endoff)
2117{
2118	int check_max, ret, err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2119
2120retry:
2121	if (endoff > 0)
2122		check_max_size(&ci->vfs_inode, endoff);
2123	check_max = 0;
2124	err = 0;
2125	ret = wait_event_interruptible(ci->i_cap_wq,
2126				       try_get_cap_refs(ci, need, want,
2127							got, endoff,
2128							&check_max, &err));
2129	if (err)
2130		ret = err;
2131	if (check_max)
2132		goto retry;
2133	return ret;
 
 
 
 
 
2134}
2135
2136/*
2137 * Take cap refs.  Caller must already know we hold at least one ref
2138 * on the caps in question or we don't know this is safe.
2139 */
2140void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2141{
2142	spin_lock(&ci->i_ceph_lock);
2143	__take_cap_refs(ci, caps);
2144	spin_unlock(&ci->i_ceph_lock);
2145}
2146
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2147/*
2148 * Release cap refs.
2149 *
2150 * If we released the last ref on any given cap, call ceph_check_caps
2151 * to release (or schedule a release).
2152 *
2153 * If we are releasing a WR cap (from a sync write), finalize any affected
2154 * cap_snap, and wake up any waiters.
2155 */
2156void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2157{
2158	struct inode *inode = &ci->vfs_inode;
2159	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2160	struct ceph_cap_snap *capsnap;
2161
2162	spin_lock(&ci->i_ceph_lock);
2163	if (had & CEPH_CAP_PIN)
2164		--ci->i_pin_ref;
2165	if (had & CEPH_CAP_FILE_RD)
2166		if (--ci->i_rd_ref == 0)
2167			last++;
2168	if (had & CEPH_CAP_FILE_CACHE)
2169		if (--ci->i_rdcache_ref == 0)
2170			last++;
2171	if (had & CEPH_CAP_FILE_BUFFER) {
2172		if (--ci->i_wb_ref == 0) {
2173			last++;
2174			put++;
2175		}
2176		dout("put_cap_refs %p wb %d -> %d (?)\n",
2177		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2178	}
2179	if (had & CEPH_CAP_FILE_WR)
2180		if (--ci->i_wr_ref == 0) {
2181			last++;
2182			if (!list_empty(&ci->i_cap_snaps)) {
2183				capsnap = list_first_entry(&ci->i_cap_snaps,
2184						     struct ceph_cap_snap,
2185						     ci_item);
2186				if (capsnap->writing) {
2187					capsnap->writing = 0;
2188					flushsnaps =
2189						__ceph_finish_cap_snap(ci,
2190								       capsnap);
2191					wake = 1;
2192				}
 
 
 
 
 
 
 
2193			}
 
 
 
2194		}
2195	spin_unlock(&ci->i_ceph_lock);
2196
2197	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2198	     last ? " last" : "", put ? " put" : "");
2199
2200	if (last && !flushsnaps)
2201		ceph_check_caps(ci, 0, NULL);
2202	else if (flushsnaps)
2203		ceph_flush_snaps(ci);
2204	if (wake)
2205		wake_up_all(&ci->i_cap_wq);
2206	if (put)
2207		iput(inode);
2208}
2209
2210/*
2211 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2212 * context.  Adjust per-snap dirty page accounting as appropriate.
2213 * Once all dirty data for a cap_snap is flushed, flush snapped file
2214 * metadata back to the MDS.  If we dropped the last ref, call
2215 * ceph_check_caps.
2216 */
2217void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2218				struct ceph_snap_context *snapc)
2219{
2220	struct inode *inode = &ci->vfs_inode;
2221	int last = 0;
2222	int complete_capsnap = 0;
2223	int drop_capsnap = 0;
2224	int found = 0;
2225	struct ceph_cap_snap *capsnap = NULL;
 
 
 
 
 
2226
2227	spin_lock(&ci->i_ceph_lock);
2228	ci->i_wrbuffer_ref -= nr;
2229	last = !ci->i_wrbuffer_ref;
 
 
 
2230
2231	if (ci->i_head_snapc == snapc) {
2232		ci->i_wrbuffer_ref_head -= nr;
2233		if (ci->i_wrbuffer_ref_head == 0 &&
2234		    ci->i_dirty_caps == 0 && ci->i_flushing_caps == 0) {
 
 
2235			BUG_ON(!ci->i_head_snapc);
2236			ceph_put_snap_context(ci->i_head_snapc);
2237			ci->i_head_snapc = NULL;
2238		}
2239		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2240		     inode,
2241		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2242		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2243		     last ? " LAST" : "");
2244	} else {
2245		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2246			if (capsnap->context == snapc) {
2247				found = 1;
2248				break;
2249			}
2250		}
2251		BUG_ON(!found);
2252		capsnap->dirty_pages -= nr;
2253		if (capsnap->dirty_pages == 0) {
2254			complete_capsnap = 1;
2255			if (capsnap->dirty == 0)
2256				/* cap writeback completed before we created
2257				 * the cap_snap; no FLUSHSNAP is needed */
2258				drop_capsnap = 1;
 
 
 
 
2259		}
2260		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2261		     " snap %lld %d/%d -> %d/%d %s%s%s\n",
2262		     inode, capsnap, capsnap->context->seq,
2263		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2264		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2265		     last ? " (wrbuffer last)" : "",
2266		     complete_capsnap ? " (complete capsnap)" : "",
2267		     drop_capsnap ? " (drop capsnap)" : "");
2268		if (drop_capsnap) {
2269			ceph_put_snap_context(capsnap->context);
2270			list_del(&capsnap->ci_item);
2271			list_del(&capsnap->flushing_item);
2272			ceph_put_cap_snap(capsnap);
2273		}
2274	}
2275
2276	spin_unlock(&ci->i_ceph_lock);
2277
2278	if (last) {
2279		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 
 
 
 
 
 
2280		iput(inode);
2281	} else if (complete_capsnap) {
2282		ceph_flush_snaps(ci);
2283		wake_up_all(&ci->i_cap_wq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2284	}
2285	if (drop_capsnap)
2286		iput(inode);
2287}
2288
2289/*
2290 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
2291 * actually be a revocation if it specifies a smaller cap set.)
2292 *
2293 * caller holds s_mutex and i_ceph_lock, we drop both.
2294 *
2295 * return value:
2296 *  0 - ok
2297 *  1 - check_caps on auth cap only (writeback)
2298 *  2 - check_caps (ack revoke)
2299 */
2300static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
 
 
 
 
2301			     struct ceph_mds_session *session,
2302			     struct ceph_cap *cap,
2303			     struct ceph_buffer *xattr_buf)
2304		__releases(ci->i_ceph_lock)
2305{
2306	struct ceph_inode_info *ci = ceph_inode(inode);
2307	int mds = session->s_mds;
2308	int seq = le32_to_cpu(grant->seq);
2309	int newcaps = le32_to_cpu(grant->caps);
2310	int issued, implemented, used, wanted, dirty;
2311	u64 size = le64_to_cpu(grant->size);
2312	u64 max_size = le64_to_cpu(grant->max_size);
2313	struct timespec mtime, atime, ctime;
2314	int check_caps = 0;
2315	int wake = 0;
2316	int writeback = 0;
2317	int revoked_rdcache = 0;
2318	int queue_invalidate = 0;
 
 
2319
2320	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
2321	     inode, cap, mds, seq, ceph_cap_string(newcaps));
2322	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2323		inode->i_size);
2324
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2325	/*
2326	 * If CACHE is being revoked, and we have no dirty buffers,
2327	 * try to invalidate (once).  (If there are dirty buffers, we
2328	 * will invalidate _after_ writeback.)
2329	 */
2330	if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
 
2331	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2332	    !ci->i_wrbuffer_ref) {
2333		if (try_nonblocking_invalidate(inode) == 0) {
2334			revoked_rdcache = 1;
2335		} else {
2336			/* there were locked pages.. invalidate later
2337			   in a separate thread. */
2338			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2339				queue_invalidate = 1;
2340				ci->i_rdcache_revoking = ci->i_rdcache_gen;
2341			}
2342		}
2343	}
2344
2345	/* side effects now are allowed */
2346
2347	issued = __ceph_caps_issued(ci, &implemented);
2348	issued |= implemented | __ceph_caps_dirty(ci);
2349
2350	cap->cap_gen = session->s_cap_gen;
 
2351
2352	__check_cap_issue(ci, cap, newcaps);
2353
2354	if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
 
2355		inode->i_mode = le32_to_cpu(grant->mode);
2356		inode->i_uid = le32_to_cpu(grant->uid);
2357		inode->i_gid = le32_to_cpu(grant->gid);
2358		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2359		     inode->i_uid, inode->i_gid);
 
2360	}
2361
2362	if ((issued & CEPH_CAP_LINK_EXCL) == 0)
 
2363		set_nlink(inode, le32_to_cpu(grant->nlink));
 
 
 
 
2364
2365	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
2366		int len = le32_to_cpu(grant->xattr_len);
2367		u64 version = le64_to_cpu(grant->xattr_version);
2368
2369		if (version > ci->i_xattrs.version) {
2370			dout(" got new xattrs v%llu on %p len %d\n",
2371			     version, inode, len);
2372			if (ci->i_xattrs.blob)
2373				ceph_buffer_put(ci->i_xattrs.blob);
2374			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2375			ci->i_xattrs.version = version;
 
2376		}
2377	}
2378
2379	/* size/ctime/mtime/atime? */
2380	ceph_fill_file_size(inode, issued,
2381			    le32_to_cpu(grant->truncate_seq),
2382			    le64_to_cpu(grant->truncate_size), size);
2383	ceph_decode_timespec(&mtime, &grant->mtime);
2384	ceph_decode_timespec(&atime, &grant->atime);
2385	ceph_decode_timespec(&ctime, &grant->ctime);
2386	ceph_fill_file_time(inode, issued,
2387			    le32_to_cpu(grant->time_warp_seq), &ctime, &mtime,
2388			    &atime);
2389
2390	/* max size increase? */
2391	if (max_size != ci->i_max_size) {
2392		dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
2393		ci->i_max_size = max_size;
2394		if (max_size >= ci->i_wanted_max_size) {
2395			ci->i_wanted_max_size = 0;  /* reset */
2396			ci->i_requested_max_size = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2397		}
2398		wake = 1;
2399	}
2400
2401	/* check cap bits */
2402	wanted = __ceph_caps_wanted(ci);
2403	used = __ceph_caps_used(ci);
2404	dirty = __ceph_caps_dirty(ci);
2405	dout(" my wanted = %s, used = %s, dirty %s\n",
2406	     ceph_cap_string(wanted),
2407	     ceph_cap_string(used),
2408	     ceph_cap_string(dirty));
2409	if (wanted != le32_to_cpu(grant->wanted)) {
2410		dout("mds wanted %s -> %s\n",
2411		     ceph_cap_string(le32_to_cpu(grant->wanted)),
2412		     ceph_cap_string(wanted));
2413		grant->wanted = cpu_to_le32(wanted);
 
 
2414	}
2415
2416	cap->seq = seq;
2417
2418	/* file layout may have changed */
2419	ci->i_layout = grant->layout;
2420
2421	/* revocation, grant, or no-op? */
2422	if (cap->issued & ~newcaps) {
2423		int revoking = cap->issued & ~newcaps;
2424
2425		dout("revocation: %s -> %s (revoking %s)\n",
2426		     ceph_cap_string(cap->issued),
2427		     ceph_cap_string(newcaps),
2428		     ceph_cap_string(revoking));
2429		if (revoking & used & CEPH_CAP_FILE_BUFFER)
2430			writeback = 1;  /* initiate writeback; will delay ack */
2431		else if (revoking == CEPH_CAP_FILE_CACHE &&
2432			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2433			 queue_invalidate)
2434			; /* do nothing yet, invalidation will be queued */
2435		else if (cap == ci->i_auth_cap)
2436			check_caps = 1; /* check auth cap only */
2437		else
2438			check_caps = 2; /* check all caps */
2439		cap->issued = newcaps;
2440		cap->implemented |= newcaps;
2441	} else if (cap->issued == newcaps) {
2442		dout("caps unchanged: %s -> %s\n",
2443		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
2444	} else {
2445		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
2446		     ceph_cap_string(newcaps));
 
 
 
 
 
2447		cap->issued = newcaps;
2448		cap->implemented |= newcaps; /* add bits only, to
2449					      * avoid stepping on a
2450					      * pending revocation */
2451		wake = 1;
2452	}
2453	BUG_ON(cap->issued & ~cap->implemented);
2454
2455	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2456	if (writeback)
2457		/*
2458		 * queue inode for writeback: we can't actually call
2459		 * filemap_write_and_wait, etc. from message handler
2460		 * context.
2461		 */
2462		ceph_queue_writeback(inode);
2463	if (queue_invalidate)
2464		ceph_queue_invalidate(inode);
 
 
2465	if (wake)
2466		wake_up_all(&ci->i_cap_wq);
2467
2468	if (check_caps == 1)
2469		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
2470				session);
2471	else if (check_caps == 2)
2472		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
2473	else
2474		mutex_unlock(&session->s_mutex);
2475}
2476
2477/*
2478 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
2479 * MDS has been safely committed.
2480 */
2481static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
2482				 struct ceph_mds_caps *m,
2483				 struct ceph_mds_session *session,
2484				 struct ceph_cap *cap)
2485	__releases(ci->i_ceph_lock)
2486{
2487	struct ceph_inode_info *ci = ceph_inode(inode);
2488	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 
 
2489	unsigned seq = le32_to_cpu(m->seq);
2490	int dirty = le32_to_cpu(m->dirty);
2491	int cleaned = 0;
2492	int drop = 0;
2493	int i;
2494
2495	for (i = 0; i < CEPH_CAP_BITS; i++)
2496		if ((dirty & (1 << i)) &&
2497		    flush_tid == ci->i_cap_flush_tid[i])
2498			cleaned |= 1 << i;
 
 
 
 
 
 
 
 
 
 
 
 
2499
2500	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
2501	     " flushing %s -> %s\n",
2502	     inode, session->s_mds, seq, ceph_cap_string(dirty),
2503	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
2504	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
2505
2506	if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
2507		goto out;
2508
2509	ci->i_flushing_caps &= ~cleaned;
2510
2511	spin_lock(&mdsc->cap_dirty_lock);
 
 
 
 
 
 
2512	if (ci->i_flushing_caps == 0) {
2513		list_del_init(&ci->i_flushing_item);
2514		if (!list_empty(&session->s_cap_flushing))
2515			dout(" mds%d still flushing cap on %p\n",
2516			     session->s_mds,
2517			     &list_entry(session->s_cap_flushing.next,
2518					 struct ceph_inode_info,
2519					 i_flushing_item)->vfs_inode);
 
 
 
2520		mdsc->num_cap_flushing--;
2521		wake_up_all(&mdsc->cap_flushing_wq);
2522		dout(" inode %p now !flushing\n", inode);
2523
2524		if (ci->i_dirty_caps == 0) {
2525			dout(" inode %p now clean\n", inode);
2526			BUG_ON(!list_empty(&ci->i_dirty_item));
2527			drop = 1;
2528			if (ci->i_wrbuffer_ref_head == 0) {
 
2529				BUG_ON(!ci->i_head_snapc);
2530				ceph_put_snap_context(ci->i_head_snapc);
2531				ci->i_head_snapc = NULL;
2532			}
2533		} else {
2534			BUG_ON(list_empty(&ci->i_dirty_item));
2535		}
2536	}
2537	spin_unlock(&mdsc->cap_dirty_lock);
2538	wake_up_all(&ci->i_cap_wq);
2539
2540out:
2541	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
2542	if (drop)
2543		iput(inode);
2544}
2545
2546/*
2547 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
2548 * throw away our cap_snap.
2549 *
2550 * Caller hold s_mutex.
2551 */
2552static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
2553				     struct ceph_mds_caps *m,
2554				     struct ceph_mds_session *session)
2555{
2556	struct ceph_inode_info *ci = ceph_inode(inode);
 
2557	u64 follows = le64_to_cpu(m->snap_follows);
2558	struct ceph_cap_snap *capsnap;
2559	int drop = 0;
 
 
2560
2561	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
2562	     inode, ci, session->s_mds, follows);
2563
2564	spin_lock(&ci->i_ceph_lock);
2565	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2566		if (capsnap->follows == follows) {
2567			if (capsnap->flush_tid != flush_tid) {
2568				dout(" cap_snap %p follows %lld tid %lld !="
2569				     " %lld\n", capsnap, follows,
2570				     flush_tid, capsnap->flush_tid);
2571				break;
2572			}
2573			WARN_ON(capsnap->dirty_pages || capsnap->writing);
2574			dout(" removing %p cap_snap %p follows %lld\n",
2575			     inode, capsnap, follows);
2576			ceph_put_snap_context(capsnap->context);
2577			list_del(&capsnap->ci_item);
2578			list_del(&capsnap->flushing_item);
2579			ceph_put_cap_snap(capsnap);
2580			drop = 1;
2581			break;
2582		} else {
2583			dout(" skipping cap_snap %p follows %lld\n",
2584			     capsnap, capsnap->follows);
2585		}
2586	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2587	spin_unlock(&ci->i_ceph_lock);
2588	if (drop)
 
 
 
 
 
 
2589		iput(inode);
 
2590}
2591
2592/*
2593 * Handle TRUNC from MDS, indicating file truncation.
2594 *
2595 * caller hold s_mutex.
2596 */
2597static void handle_cap_trunc(struct inode *inode,
2598			     struct ceph_mds_caps *trunc,
2599			     struct ceph_mds_session *session)
2600	__releases(ci->i_ceph_lock)
2601{
2602	struct ceph_inode_info *ci = ceph_inode(inode);
2603	int mds = session->s_mds;
2604	int seq = le32_to_cpu(trunc->seq);
2605	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
2606	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
2607	u64 size = le64_to_cpu(trunc->size);
2608	int implemented = 0;
2609	int dirty = __ceph_caps_dirty(ci);
2610	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
2611	int queue_trunc = 0;
2612
2613	issued |= implemented | dirty;
2614
2615	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
2616	     inode, mds, seq, truncate_size, truncate_seq);
2617	queue_trunc = ceph_fill_file_size(inode, issued,
2618					  truncate_seq, truncate_size, size);
2619	spin_unlock(&ci->i_ceph_lock);
2620
2621	if (queue_trunc)
2622		ceph_queue_vmtruncate(inode);
2623}
2624
2625/*
2626 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
2627 * different one.  If we are the most recent migration we've seen (as
2628 * indicated by mseq), make note of the migrating cap bits for the
2629 * duration (until we see the corresponding IMPORT).
2630 *
2631 * caller holds s_mutex
2632 */
2633static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
2634			      struct ceph_mds_session *session,
2635			      int *open_target_sessions)
2636{
2637	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 
 
2638	struct ceph_inode_info *ci = ceph_inode(inode);
 
 
 
 
2639	int mds = session->s_mds;
2640	unsigned mseq = le32_to_cpu(ex->migrate_seq);
2641	struct ceph_cap *cap = NULL, *t;
2642	struct rb_node *p;
2643	int remember = 1;
2644
2645	dout("handle_cap_export inode %p ci %p mds%d mseq %d\n",
2646	     inode, ci, mds, mseq);
 
 
 
 
 
 
 
2647
 
 
 
2648	spin_lock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
2649
2650	/* make sure we haven't seen a higher mseq */
2651	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
2652		t = rb_entry(p, struct ceph_cap, ci_node);
2653		if (ceph_seq_cmp(t->mseq, mseq) > 0) {
2654			dout(" higher mseq on cap from mds%d\n",
2655			     t->session->s_mds);
2656			remember = 0;
2657		}
2658		if (t->session->s_mds == mds)
2659			cap = t;
2660	}
2661
2662	if (cap) {
2663		if (remember) {
2664			/* make note */
2665			ci->i_cap_exporting_mds = mds;
2666			ci->i_cap_exporting_mseq = mseq;
2667			ci->i_cap_exporting_issued = cap->issued;
2668
2669			/*
2670			 * make sure we have open sessions with all possible
2671			 * export targets, so that we get the matching IMPORT
2672			 */
2673			*open_target_sessions = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2674
2675			/*
2676			 * we can't flush dirty caps that we've seen the
2677			 * EXPORT but no IMPORT for
2678			 */
2679			spin_lock(&mdsc->cap_dirty_lock);
2680			if (!list_empty(&ci->i_dirty_item)) {
2681				dout(" moving %p to cap_dirty_migrating\n",
2682				     inode);
2683				list_move(&ci->i_dirty_item,
2684					  &mdsc->cap_dirty_migrating);
2685			}
2686			spin_unlock(&mdsc->cap_dirty_lock);
2687		}
2688		__ceph_remove_cap(cap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2689	}
2690	/* else, we already released it */
2691
 
2692	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
2693}
2694
2695/*
2696 * Handle cap IMPORT.  If there are temp bits from an older EXPORT,
2697 * clean them up.
2698 *
2699 * caller holds s_mutex.
2700 */
2701static void handle_cap_import(struct ceph_mds_client *mdsc,
2702			      struct inode *inode, struct ceph_mds_caps *im,
 
2703			      struct ceph_mds_session *session,
2704			      void *snaptrace, int snaptrace_len)
 
2705{
2706	struct ceph_inode_info *ci = ceph_inode(inode);
 
2707	int mds = session->s_mds;
2708	unsigned issued = le32_to_cpu(im->caps);
 
2709	unsigned wanted = le32_to_cpu(im->wanted);
2710	unsigned seq = le32_to_cpu(im->seq);
2711	unsigned mseq = le32_to_cpu(im->migrate_seq);
2712	u64 realmino = le64_to_cpu(im->realm);
2713	u64 cap_id = le64_to_cpu(im->cap_id);
 
 
2714
2715	if (ci->i_cap_exporting_mds >= 0 &&
2716	    ceph_seq_cmp(ci->i_cap_exporting_mseq, mseq) < 0) {
2717		dout("handle_cap_import inode %p ci %p mds%d mseq %d"
2718		     " - cleared exporting from mds%d\n",
2719		     inode, ci, mds, mseq,
2720		     ci->i_cap_exporting_mds);
2721		ci->i_cap_exporting_issued = 0;
2722		ci->i_cap_exporting_mseq = 0;
2723		ci->i_cap_exporting_mds = -1;
 
2724
2725		spin_lock(&mdsc->cap_dirty_lock);
2726		if (!list_empty(&ci->i_dirty_item)) {
2727			dout(" moving %p back to cap_dirty\n", inode);
2728			list_move(&ci->i_dirty_item, &mdsc->cap_dirty);
 
 
 
 
2729		}
2730		spin_unlock(&mdsc->cap_dirty_lock);
2731	} else {
2732		dout("handle_cap_import inode %p ci %p mds%d mseq %d\n",
2733		     inode, ci, mds, mseq);
 
 
2734	}
2735
2736	down_write(&mdsc->snap_rwsem);
2737	ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
2738			       false);
2739	downgrade_write(&mdsc->snap_rwsem);
2740	ceph_add_cap(inode, session, cap_id, -1,
2741		     issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
2742		     NULL /* no caps context */);
2743	kick_flushing_inode_caps(mdsc, session, inode);
2744	up_read(&mdsc->snap_rwsem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2745
2746	/* make sure we re-request max_size, if necessary */
2747	spin_lock(&ci->i_ceph_lock);
2748	ci->i_requested_max_size = 0;
2749	spin_unlock(&ci->i_ceph_lock);
 
 
2750}
2751
2752/*
2753 * Handle a caps message from the MDS.
2754 *
2755 * Identify the appropriate session, inode, and call the right handler
2756 * based on the cap op.
2757 */
2758void ceph_handle_caps(struct ceph_mds_session *session,
2759		      struct ceph_msg *msg)
2760{
2761	struct ceph_mds_client *mdsc = session->s_mdsc;
2762	struct super_block *sb = mdsc->fsc->sb;
2763	struct inode *inode;
2764	struct ceph_inode_info *ci;
2765	struct ceph_cap *cap;
2766	struct ceph_mds_caps *h;
 
 
 
2767	int mds = session->s_mds;
2768	int op;
2769	u32 seq, mseq;
2770	struct ceph_vino vino;
2771	u64 cap_id;
2772	u64 size, max_size;
2773	u64 tid;
 
 
 
2774	void *snaptrace;
2775	size_t snaptrace_len;
2776	void *flock;
2777	u32 flock_len;
2778	int open_target_sessions = 0;
2779
2780	dout("handle_caps from mds%d\n", mds);
2781
2782	/* decode */
 
2783	tid = le64_to_cpu(msg->hdr.tid);
2784	if (msg->front.iov_len < sizeof(*h))
2785		goto bad;
2786	h = msg->front.iov_base;
2787	op = le32_to_cpu(h->op);
2788	vino.ino = le64_to_cpu(h->ino);
2789	vino.snap = CEPH_NOSNAP;
2790	cap_id = le64_to_cpu(h->cap_id);
2791	seq = le32_to_cpu(h->seq);
2792	mseq = le32_to_cpu(h->migrate_seq);
2793	size = le64_to_cpu(h->size);
2794	max_size = le64_to_cpu(h->max_size);
2795
2796	snaptrace = h + 1;
2797	snaptrace_len = le32_to_cpu(h->snap_trace_len);
 
2798
2799	if (le16_to_cpu(msg->hdr.version) >= 2) {
2800		void *p, *end;
2801
2802		p = snaptrace + snaptrace_len;
2803		end = msg->front.iov_base + msg->front.iov_len;
2804		ceph_decode_32_safe(&p, end, flock_len, bad);
2805		flock = p;
2806	} else {
2807		flock = NULL;
2808		flock_len = 0;
 
 
 
 
 
 
 
 
 
 
 
2809	}
2810
2811	mutex_lock(&session->s_mutex);
2812	session->s_seq++;
2813	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
2814	     (unsigned)seq);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2815
2816	/* lookup ino */
2817	inode = ceph_find_inode(sb, vino);
2818	ci = ceph_inode(inode);
2819	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
2820	     vino.snap, inode);
 
 
 
 
 
 
2821	if (!inode) {
2822		dout(" i don't have ino %llx\n", vino.ino);
2823
2824		if (op == CEPH_CAP_OP_IMPORT)
2825			__queue_cap_release(session, vino.ino, cap_id,
2826					    mseq, seq);
 
 
 
 
 
 
 
 
 
 
 
2827		goto flush_cap_releases;
2828	}
2829
2830	/* these will work even if we don't have a cap yet */
2831	switch (op) {
2832	case CEPH_CAP_OP_FLUSHSNAP_ACK:
2833		handle_cap_flushsnap_ack(inode, tid, h, session);
2834		goto done;
2835
2836	case CEPH_CAP_OP_EXPORT:
2837		handle_cap_export(inode, h, session, &open_target_sessions);
2838		goto done;
2839
2840	case CEPH_CAP_OP_IMPORT:
2841		handle_cap_import(mdsc, inode, h, session,
2842				  snaptrace, snaptrace_len);
2843		ceph_check_caps(ceph_inode(inode), 0, session);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2844		goto done_unlocked;
2845	}
2846
2847	/* the rest require a cap */
2848	spin_lock(&ci->i_ceph_lock);
2849	cap = __get_cap_for_mds(ceph_inode(inode), mds);
2850	if (!cap) {
2851		dout(" no cap on %p ino %llx.%llx from mds%d\n",
2852		     inode, ceph_ino(inode), ceph_snap(inode), mds);
2853		spin_unlock(&ci->i_ceph_lock);
2854		goto flush_cap_releases;
2855	}
2856
2857	/* note that each of these drops i_ceph_lock for us */
2858	switch (op) {
2859	case CEPH_CAP_OP_REVOKE:
2860	case CEPH_CAP_OP_GRANT:
2861		handle_cap_grant(inode, h, session, cap, msg->middle);
 
 
 
 
2862		goto done_unlocked;
2863
2864	case CEPH_CAP_OP_FLUSH_ACK:
2865		handle_cap_flush_ack(inode, tid, h, session, cap);
2866		break;
2867
2868	case CEPH_CAP_OP_TRUNC:
2869		handle_cap_trunc(inode, h, session);
2870		break;
2871
2872	default:
2873		spin_unlock(&ci->i_ceph_lock);
2874		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
2875		       ceph_cap_op_name(op));
2876	}
2877
2878	goto done;
2879
2880flush_cap_releases:
2881	/*
2882	 * send any full release message to try to move things
2883	 * along for the mds (who clearly thinks we still have this
2884	 * cap).
2885	 */
2886	ceph_add_cap_releases(mdsc, session);
2887	ceph_send_cap_releases(mdsc, session);
2888
2889done:
2890	mutex_unlock(&session->s_mutex);
2891done_unlocked:
2892	if (inode)
2893		iput(inode);
2894	if (open_target_sessions)
2895		ceph_mdsc_open_export_target_sessions(mdsc, session);
2896	return;
2897
2898bad:
2899	pr_err("ceph_handle_caps: corrupt message\n");
2900	ceph_msg_dump(msg);
2901	return;
2902}
2903
2904/*
2905 * Delayed work handler to process end of delayed cap release LRU list.
2906 */
2907void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
2908{
 
2909	struct ceph_inode_info *ci;
2910	int flags = CHECK_CAPS_NODELAY;
2911
2912	dout("check_delayed_caps\n");
2913	while (1) {
2914		spin_lock(&mdsc->cap_delay_lock);
2915		if (list_empty(&mdsc->cap_delay_list))
2916			break;
2917		ci = list_first_entry(&mdsc->cap_delay_list,
2918				      struct ceph_inode_info,
2919				      i_cap_delay_list);
2920		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
2921		    time_before(jiffies, ci->i_hold_caps_max))
2922			break;
2923		list_del_init(&ci->i_cap_delay_list);
 
 
2924		spin_unlock(&mdsc->cap_delay_lock);
2925		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
2926		ceph_check_caps(ci, flags, NULL);
 
 
 
 
2927	}
2928	spin_unlock(&mdsc->cap_delay_lock);
2929}
2930
2931/*
2932 * Flush all dirty caps to the mds
2933 */
2934void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
2935{
2936	struct ceph_inode_info *ci;
2937	struct inode *inode;
2938
2939	dout("flush_dirty_caps\n");
2940	spin_lock(&mdsc->cap_dirty_lock);
2941	while (!list_empty(&mdsc->cap_dirty)) {
2942		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
2943				      i_dirty_item);
2944		inode = &ci->vfs_inode;
2945		ihold(inode);
2946		dout("flush_dirty_caps %p\n", inode);
2947		spin_unlock(&mdsc->cap_dirty_lock);
2948		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
2949		iput(inode);
2950		spin_lock(&mdsc->cap_dirty_lock);
2951	}
2952	spin_unlock(&mdsc->cap_dirty_lock);
2953	dout("flush_dirty_caps done\n");
2954}
2955
 
 
 
 
 
 
 
 
 
 
2956/*
2957 * Drop open file reference.  If we were the last open file,
2958 * we may need to release capabilities to the MDS (or schedule
2959 * their delayed release).
2960 */
2961void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
2962{
2963	struct inode *inode = &ci->vfs_inode;
2964	int last = 0;
2965
2966	spin_lock(&ci->i_ceph_lock);
2967	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
2968	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
2969	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
2970	if (--ci->i_nr_by_mode[fmode] == 0)
2971		last++;
 
 
 
 
 
 
2972	spin_unlock(&ci->i_ceph_lock);
2973
2974	if (last && ci->i_vino.snap == CEPH_NOSNAP)
2975		ceph_check_caps(ci, 0, NULL);
2976}
2977
2978/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2979 * Helpers for embedding cap and dentry lease releases into mds
2980 * requests.
2981 *
2982 * @force is used by dentry_release (below) to force inclusion of a
2983 * record for the directory inode, even when there aren't any caps to
2984 * drop.
2985 */
2986int ceph_encode_inode_release(void **p, struct inode *inode,
2987			      int mds, int drop, int unless, int force)
2988{
2989	struct ceph_inode_info *ci = ceph_inode(inode);
2990	struct ceph_cap *cap;
2991	struct ceph_mds_request_release *rel = *p;
2992	int used, dirty;
2993	int ret = 0;
2994
2995	spin_lock(&ci->i_ceph_lock);
2996	used = __ceph_caps_used(ci);
2997	dirty = __ceph_caps_dirty(ci);
2998
2999	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
3000	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3001	     ceph_cap_string(unless));
3002
3003	/* only drop unused, clean caps */
3004	drop &= ~(used | dirty);
3005
3006	cap = __get_cap_for_mds(ci, mds);
3007	if (cap && __cap_is_valid(cap)) {
3008		if (force ||
3009		    ((cap->issued & drop) &&
3010		     (cap->issued & unless) == 0)) {
3011			if ((cap->issued & drop) &&
3012			    (cap->issued & unless) == 0) {
3013				dout("encode_inode_release %p cap %p %s -> "
3014				     "%s\n", inode, cap,
 
 
 
 
 
 
 
 
 
 
 
 
3015				     ceph_cap_string(cap->issued),
3016				     ceph_cap_string(cap->issued & ~drop));
 
 
 
3017				cap->issued &= ~drop;
3018				cap->implemented &= ~drop;
3019				if (ci->i_ceph_flags & CEPH_I_NODELAY) {
3020					int wanted = __ceph_caps_wanted(ci);
3021					dout("  wanted %s -> %s (act %s)\n",
3022					     ceph_cap_string(cap->mds_wanted),
3023					     ceph_cap_string(cap->mds_wanted &
3024							     ~wanted),
3025					     ceph_cap_string(wanted));
3026					cap->mds_wanted &= wanted;
3027				}
3028			} else {
3029				dout("encode_inode_release %p cap %p %s"
3030				     " (force)\n", inode, cap,
3031				     ceph_cap_string(cap->issued));
3032			}
3033
3034			rel->ino = cpu_to_le64(ceph_ino(inode));
3035			rel->cap_id = cpu_to_le64(cap->cap_id);
3036			rel->seq = cpu_to_le32(cap->seq);
3037			rel->issue_seq = cpu_to_le32(cap->issue_seq),
3038			rel->mseq = cpu_to_le32(cap->mseq);
3039			rel->caps = cpu_to_le32(cap->issued);
3040			rel->wanted = cpu_to_le32(cap->mds_wanted);
3041			rel->dname_len = 0;
3042			rel->dname_seq = 0;
3043			*p += sizeof(*rel);
3044			ret = 1;
3045		} else {
3046			dout("encode_inode_release %p cap %p %s\n",
3047			     inode, cap, ceph_cap_string(cap->issued));
3048		}
3049	}
3050	spin_unlock(&ci->i_ceph_lock);
3051	return ret;
3052}
3053
3054int ceph_encode_dentry_release(void **p, struct dentry *dentry,
 
3055			       int mds, int drop, int unless)
3056{
3057	struct inode *dir = dentry->d_parent->d_inode;
3058	struct ceph_mds_request_release *rel = *p;
3059	struct ceph_dentry_info *di = ceph_dentry(dentry);
3060	int force = 0;
3061	int ret;
3062
3063	/*
3064	 * force an record for the directory caps if we have a dentry lease.
3065	 * this is racy (can't take i_ceph_lock and d_lock together), but it
3066	 * doesn't have to be perfect; the mds will revoke anything we don't
3067	 * release.
3068	 */
3069	spin_lock(&dentry->d_lock);
3070	if (di->lease_session && di->lease_session->s_mds == mds)
3071		force = 1;
 
 
 
 
3072	spin_unlock(&dentry->d_lock);
3073
3074	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
 
3075
3076	spin_lock(&dentry->d_lock);
3077	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
3078		dout("encode_dentry_release %p mds%d seq %d\n",
3079		     dentry, mds, (int)di->lease_seq);
3080		rel->dname_len = cpu_to_le32(dentry->d_name.len);
3081		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
3082		*p += dentry->d_name.len;
3083		rel->dname_seq = cpu_to_le32(di->lease_seq);
3084		__ceph_mdsc_drop_dentry_lease(dentry);
3085	}
3086	spin_unlock(&dentry->d_lock);
3087	return ret;
3088}