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v4.10.11
 
   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 "cache.h"
  14#include <linux/ceph/decode.h>
  15#include <linux/ceph/messenger.h>
  16
  17/*
  18 * Capability management
  19 *
  20 * The Ceph metadata servers control client access to inode metadata
  21 * and file data by issuing capabilities, granting clients permission
  22 * to read and/or write both inode field and file data to OSDs
  23 * (storage nodes).  Each capability consists of a set of bits
  24 * indicating which operations are allowed.
  25 *
  26 * If the client holds a *_SHARED cap, the client has a coherent value
  27 * that can be safely read from the cached inode.
  28 *
  29 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
  30 * client is allowed to change inode attributes (e.g., file size,
  31 * mtime), note its dirty state in the ceph_cap, and asynchronously
  32 * flush that metadata change to the MDS.
  33 *
  34 * In the event of a conflicting operation (perhaps by another
  35 * client), the MDS will revoke the conflicting client capabilities.
  36 *
  37 * In order for a client to cache an inode, it must hold a capability
  38 * with at least one MDS server.  When inodes are released, release
  39 * notifications are batched and periodically sent en masse to the MDS
  40 * cluster to release server state.
  41 */
  42
  43static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc);
  44static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
  45				 struct ceph_mds_session *session,
  46				 struct ceph_inode_info *ci,
  47				 u64 oldest_flush_tid);
  48
  49/*
  50 * Generate readable cap strings for debugging output.
  51 */
  52#define MAX_CAP_STR 20
  53static char cap_str[MAX_CAP_STR][40];
  54static DEFINE_SPINLOCK(cap_str_lock);
  55static int last_cap_str;
  56
  57static char *gcap_string(char *s, int c)
  58{
  59	if (c & CEPH_CAP_GSHARED)
  60		*s++ = 's';
  61	if (c & CEPH_CAP_GEXCL)
  62		*s++ = 'x';
  63	if (c & CEPH_CAP_GCACHE)
  64		*s++ = 'c';
  65	if (c & CEPH_CAP_GRD)
  66		*s++ = 'r';
  67	if (c & CEPH_CAP_GWR)
  68		*s++ = 'w';
  69	if (c & CEPH_CAP_GBUFFER)
  70		*s++ = 'b';
 
 
  71	if (c & CEPH_CAP_GLAZYIO)
  72		*s++ = 'l';
  73	return s;
  74}
  75
  76const char *ceph_cap_string(int caps)
  77{
  78	int i;
  79	char *s;
  80	int c;
  81
  82	spin_lock(&cap_str_lock);
  83	i = last_cap_str++;
  84	if (last_cap_str == MAX_CAP_STR)
  85		last_cap_str = 0;
  86	spin_unlock(&cap_str_lock);
  87
  88	s = cap_str[i];
  89
  90	if (caps & CEPH_CAP_PIN)
  91		*s++ = 'p';
  92
  93	c = (caps >> CEPH_CAP_SAUTH) & 3;
  94	if (c) {
  95		*s++ = 'A';
  96		s = gcap_string(s, c);
  97	}
  98
  99	c = (caps >> CEPH_CAP_SLINK) & 3;
 100	if (c) {
 101		*s++ = 'L';
 102		s = gcap_string(s, c);
 103	}
 104
 105	c = (caps >> CEPH_CAP_SXATTR) & 3;
 106	if (c) {
 107		*s++ = 'X';
 108		s = gcap_string(s, c);
 109	}
 110
 111	c = caps >> CEPH_CAP_SFILE;
 112	if (c) {
 113		*s++ = 'F';
 114		s = gcap_string(s, c);
 115	}
 116
 117	if (s == cap_str[i])
 118		*s++ = '-';
 119	*s = 0;
 120	return cap_str[i];
 121}
 122
 123void ceph_caps_init(struct ceph_mds_client *mdsc)
 124{
 125	INIT_LIST_HEAD(&mdsc->caps_list);
 126	spin_lock_init(&mdsc->caps_list_lock);
 127}
 128
 129void ceph_caps_finalize(struct ceph_mds_client *mdsc)
 130{
 131	struct ceph_cap *cap;
 132
 133	spin_lock(&mdsc->caps_list_lock);
 134	while (!list_empty(&mdsc->caps_list)) {
 135		cap = list_first_entry(&mdsc->caps_list,
 136				       struct ceph_cap, caps_item);
 137		list_del(&cap->caps_item);
 138		kmem_cache_free(ceph_cap_cachep, cap);
 139	}
 140	mdsc->caps_total_count = 0;
 141	mdsc->caps_avail_count = 0;
 142	mdsc->caps_use_count = 0;
 143	mdsc->caps_reserve_count = 0;
 144	mdsc->caps_min_count = 0;
 145	spin_unlock(&mdsc->caps_list_lock);
 146}
 147
 148void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
 
 149{
 150	spin_lock(&mdsc->caps_list_lock);
 151	mdsc->caps_min_count += delta;
 152	BUG_ON(mdsc->caps_min_count < 0);
 
 
 
 
 
 153	spin_unlock(&mdsc->caps_list_lock);
 154}
 155
 156void ceph_reserve_caps(struct ceph_mds_client *mdsc,
 157		      struct ceph_cap_reservation *ctx, int need)
 158{
 
 159	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 160	struct ceph_cap *cap;
 161	int have;
 162	int alloc = 0;
 
 
 
 
 163	LIST_HEAD(newcaps);
 164
 165	dout("reserve caps ctx=%p need=%d\n", ctx, need);
 166
 167	/* first reserve any caps that are already allocated */
 168	spin_lock(&mdsc->caps_list_lock);
 169	if (mdsc->caps_avail_count >= need)
 170		have = need;
 171	else
 172		have = mdsc->caps_avail_count;
 173	mdsc->caps_avail_count -= have;
 174	mdsc->caps_reserve_count += have;
 175	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 176					 mdsc->caps_reserve_count +
 177					 mdsc->caps_avail_count);
 178	spin_unlock(&mdsc->caps_list_lock);
 179
 180	for (i = have; i < need; i++) {
 181		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 182		if (!cap)
 183			break;
 184		list_add(&cap->caps_item, &newcaps);
 185		alloc++;
 186	}
 187	/* we didn't manage to reserve as much as we needed */
 188	if (have + alloc != need)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 189		pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
 190			ctx, need, have + alloc);
 
 
 
 
 
 
 
 
 
 191
 192	spin_lock(&mdsc->caps_list_lock);
 193	mdsc->caps_total_count += alloc;
 194	mdsc->caps_reserve_count += alloc;
 195	list_splice(&newcaps, &mdsc->caps_list);
 196
 197	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 198					 mdsc->caps_reserve_count +
 199					 mdsc->caps_avail_count);
 
 
 
 
 200	spin_unlock(&mdsc->caps_list_lock);
 201
 202	ctx->count = need;
 203	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 204	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 205	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 
 206}
 207
 208int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 209			struct ceph_cap_reservation *ctx)
 210{
 
 
 
 
 211	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
 212	if (ctx->count) {
 213		spin_lock(&mdsc->caps_list_lock);
 214		BUG_ON(mdsc->caps_reserve_count < ctx->count);
 215		mdsc->caps_reserve_count -= ctx->count;
 216		mdsc->caps_avail_count += ctx->count;
 217		ctx->count = 0;
 218		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
 219		     mdsc->caps_total_count, mdsc->caps_use_count,
 220		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 221		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 222						 mdsc->caps_reserve_count +
 223						 mdsc->caps_avail_count);
 224		spin_unlock(&mdsc->caps_list_lock);
 225	}
 226	return 0;
 227}
 228
 229struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
 230			      struct ceph_cap_reservation *ctx)
 231{
 232	struct ceph_cap *cap = NULL;
 233
 234	/* temporary, until we do something about cap import/export */
 235	if (!ctx) {
 236		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 237		if (cap) {
 238			spin_lock(&mdsc->caps_list_lock);
 239			mdsc->caps_use_count++;
 240			mdsc->caps_total_count++;
 241			spin_unlock(&mdsc->caps_list_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 242		}
 
 243		return cap;
 244	}
 245
 246	spin_lock(&mdsc->caps_list_lock);
 247	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
 248	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
 249	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 250	BUG_ON(!ctx->count);
 251	BUG_ON(ctx->count > mdsc->caps_reserve_count);
 252	BUG_ON(list_empty(&mdsc->caps_list));
 253
 254	ctx->count--;
 
 255	mdsc->caps_reserve_count--;
 256	mdsc->caps_use_count++;
 257
 258	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
 259	list_del(&cap->caps_item);
 260
 261	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 262	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 263	spin_unlock(&mdsc->caps_list_lock);
 264	return cap;
 265}
 266
 267void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
 268{
 269	spin_lock(&mdsc->caps_list_lock);
 270	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
 271	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
 272	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 273	mdsc->caps_use_count--;
 274	/*
 275	 * Keep some preallocated caps around (ceph_min_count), to
 276	 * avoid lots of free/alloc churn.
 277	 */
 278	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
 279				      mdsc->caps_min_count) {
 280		mdsc->caps_total_count--;
 281		kmem_cache_free(ceph_cap_cachep, cap);
 282	} else {
 283		mdsc->caps_avail_count++;
 284		list_add(&cap->caps_item, &mdsc->caps_list);
 285	}
 286
 287	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 288	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 289	spin_unlock(&mdsc->caps_list_lock);
 290}
 291
 292void ceph_reservation_status(struct ceph_fs_client *fsc,
 293			     int *total, int *avail, int *used, int *reserved,
 294			     int *min)
 295{
 296	struct ceph_mds_client *mdsc = fsc->mdsc;
 297
 
 
 298	if (total)
 299		*total = mdsc->caps_total_count;
 300	if (avail)
 301		*avail = mdsc->caps_avail_count;
 302	if (used)
 303		*used = mdsc->caps_use_count;
 304	if (reserved)
 305		*reserved = mdsc->caps_reserve_count;
 306	if (min)
 307		*min = mdsc->caps_min_count;
 
 
 308}
 309
 310/*
 311 * Find ceph_cap for given mds, if any.
 312 *
 313 * Called with i_ceph_lock held.
 314 */
 315static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 316{
 317	struct ceph_cap *cap;
 318	struct rb_node *n = ci->i_caps.rb_node;
 319
 320	while (n) {
 321		cap = rb_entry(n, struct ceph_cap, ci_node);
 322		if (mds < cap->mds)
 323			n = n->rb_left;
 324		else if (mds > cap->mds)
 325			n = n->rb_right;
 326		else
 327			return cap;
 328	}
 329	return NULL;
 330}
 331
 332struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 333{
 334	struct ceph_cap *cap;
 335
 336	spin_lock(&ci->i_ceph_lock);
 337	cap = __get_cap_for_mds(ci, mds);
 338	spin_unlock(&ci->i_ceph_lock);
 339	return cap;
 340}
 341
 342/*
 343 * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
 344 */
 345static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
 346{
 347	struct ceph_cap *cap;
 348	int mds = -1;
 349	struct rb_node *p;
 350
 351	/* prefer mds with WR|BUFFER|EXCL caps */
 352	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 353		cap = rb_entry(p, struct ceph_cap, ci_node);
 354		mds = cap->mds;
 355		if (cap->issued & (CEPH_CAP_FILE_WR |
 356				   CEPH_CAP_FILE_BUFFER |
 357				   CEPH_CAP_FILE_EXCL))
 358			break;
 359	}
 360	return mds;
 361}
 362
 363int ceph_get_cap_mds(struct inode *inode)
 364{
 365	struct ceph_inode_info *ci = ceph_inode(inode);
 366	int mds;
 367	spin_lock(&ci->i_ceph_lock);
 368	mds = __ceph_get_cap_mds(ceph_inode(inode));
 369	spin_unlock(&ci->i_ceph_lock);
 370	return mds;
 371}
 372
 373/*
 374 * Called under i_ceph_lock.
 375 */
 376static void __insert_cap_node(struct ceph_inode_info *ci,
 377			      struct ceph_cap *new)
 378{
 379	struct rb_node **p = &ci->i_caps.rb_node;
 380	struct rb_node *parent = NULL;
 381	struct ceph_cap *cap = NULL;
 382
 383	while (*p) {
 384		parent = *p;
 385		cap = rb_entry(parent, struct ceph_cap, ci_node);
 386		if (new->mds < cap->mds)
 387			p = &(*p)->rb_left;
 388		else if (new->mds > cap->mds)
 389			p = &(*p)->rb_right;
 390		else
 391			BUG();
 392	}
 393
 394	rb_link_node(&new->ci_node, parent, p);
 395	rb_insert_color(&new->ci_node, &ci->i_caps);
 396}
 397
 398/*
 399 * (re)set cap hold timeouts, which control the delayed release
 400 * of unused caps back to the MDS.  Should be called on cap use.
 401 */
 402static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
 403			       struct ceph_inode_info *ci)
 404{
 405	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
 406
 407	ci->i_hold_caps_min = round_jiffies(jiffies +
 408					    ma->caps_wanted_delay_min * HZ);
 409	ci->i_hold_caps_max = round_jiffies(jiffies +
 410					    ma->caps_wanted_delay_max * HZ);
 411	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
 412	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
 413}
 414
 415/*
 416 * (Re)queue cap at the end of the delayed cap release list.
 417 *
 418 * If I_FLUSH is set, leave the inode at the front of the list.
 419 *
 420 * Caller holds i_ceph_lock
 421 *    -> we take mdsc->cap_delay_lock
 422 */
 423static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 424				struct ceph_inode_info *ci)
 
 425{
 426	__cap_set_timeouts(mdsc, ci);
 427	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
 428	     ci->i_ceph_flags, ci->i_hold_caps_max);
 429	if (!mdsc->stopping) {
 430		spin_lock(&mdsc->cap_delay_lock);
 431		if (!list_empty(&ci->i_cap_delay_list)) {
 432			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 433				goto no_change;
 434			list_del_init(&ci->i_cap_delay_list);
 435		}
 
 
 436		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 437no_change:
 438		spin_unlock(&mdsc->cap_delay_lock);
 439	}
 440}
 441
 442/*
 443 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 444 * indicating we should send a cap message to flush dirty metadata
 445 * asap, and move to the front of the delayed cap list.
 446 */
 447static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 448				      struct ceph_inode_info *ci)
 449{
 450	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
 451	spin_lock(&mdsc->cap_delay_lock);
 452	ci->i_ceph_flags |= CEPH_I_FLUSH;
 453	if (!list_empty(&ci->i_cap_delay_list))
 454		list_del_init(&ci->i_cap_delay_list);
 455	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 456	spin_unlock(&mdsc->cap_delay_lock);
 457}
 458
 459/*
 460 * Cancel delayed work on cap.
 461 *
 462 * Caller must hold i_ceph_lock.
 463 */
 464static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 465			       struct ceph_inode_info *ci)
 466{
 467	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
 468	if (list_empty(&ci->i_cap_delay_list))
 469		return;
 470	spin_lock(&mdsc->cap_delay_lock);
 471	list_del_init(&ci->i_cap_delay_list);
 472	spin_unlock(&mdsc->cap_delay_lock);
 473}
 474
 475/*
 476 * Common issue checks for add_cap, handle_cap_grant.
 477 */
 478static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 479			      unsigned issued)
 480{
 481	unsigned had = __ceph_caps_issued(ci, NULL);
 482
 483	/*
 484	 * Each time we receive FILE_CACHE anew, we increment
 485	 * i_rdcache_gen.
 486	 */
 487	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 488	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) {
 489		ci->i_rdcache_gen++;
 490	}
 491
 492	/*
 493	 * if we are newly issued FILE_SHARED, mark dir not complete; we
 494	 * don't know what happened to this directory while we didn't
 495	 * have the cap.
 
 496	 */
 497	if ((issued & CEPH_CAP_FILE_SHARED) &&
 498	    (had & CEPH_CAP_FILE_SHARED) == 0) {
 499		ci->i_shared_gen++;
 500		if (S_ISDIR(ci->vfs_inode.i_mode)) {
 501			dout(" marking %p NOT complete\n", &ci->vfs_inode);
 502			__ceph_dir_clear_complete(ci);
 503		}
 504	}
 505}
 506
 507/*
 508 * Add a capability under the given MDS session.
 509 *
 510 * Caller should hold session snap_rwsem (read) and s_mutex.
 511 *
 512 * @fmode is the open file mode, if we are opening a file, otherwise
 513 * it is < 0.  (This is so we can atomically add the cap and add an
 514 * open file reference to it.)
 515 */
 516void ceph_add_cap(struct inode *inode,
 517		  struct ceph_mds_session *session, u64 cap_id,
 518		  int fmode, unsigned issued, unsigned wanted,
 519		  unsigned seq, unsigned mseq, u64 realmino, int flags,
 520		  struct ceph_cap **new_cap)
 521{
 522	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 523	struct ceph_inode_info *ci = ceph_inode(inode);
 524	struct ceph_cap *cap;
 525	int mds = session->s_mds;
 526	int actual_wanted;
 
 
 
 527
 528	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 529	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 530
 531	/*
 532	 * If we are opening the file, include file mode wanted bits
 533	 * in wanted.
 534	 */
 535	if (fmode >= 0)
 536		wanted |= ceph_caps_for_mode(fmode);
 537
 
 
 
 
 538	cap = __get_cap_for_mds(ci, mds);
 539	if (!cap) {
 540		cap = *new_cap;
 541		*new_cap = NULL;
 542
 543		cap->issued = 0;
 544		cap->implemented = 0;
 545		cap->mds = mds;
 546		cap->mds_wanted = 0;
 547		cap->mseq = 0;
 548
 549		cap->ci = ci;
 550		__insert_cap_node(ci, cap);
 551
 552		/* add to session cap list */
 553		cap->session = session;
 554		spin_lock(&session->s_cap_lock);
 555		list_add_tail(&cap->session_caps, &session->s_caps);
 556		session->s_nr_caps++;
 557		spin_unlock(&session->s_cap_lock);
 558	} else {
 
 
 
 
 
 
 
 559		/*
 560		 * auth mds of the inode changed. we received the cap export
 561		 * message, but still haven't received the cap import message.
 562		 * handle_cap_export() updated the new auth MDS' cap.
 563		 *
 564		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 565		 * a message that was send before the cap import message. So
 566		 * don't remove caps.
 567		 */
 568		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 569			WARN_ON(cap != ci->i_auth_cap);
 570			WARN_ON(cap->cap_id != cap_id);
 571			seq = cap->seq;
 572			mseq = cap->mseq;
 573			issued |= cap->issued;
 574			flags |= CEPH_CAP_FLAG_AUTH;
 575		}
 576	}
 577
 578	if (!ci->i_snap_realm) {
 
 
 579		/*
 580		 * add this inode to the appropriate snap realm
 581		 */
 582		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 583							       realmino);
 584		if (realm) {
 
 
 
 
 
 
 
 585			spin_lock(&realm->inodes_with_caps_lock);
 586			ci->i_snap_realm = realm;
 587			list_add(&ci->i_snap_realm_item,
 588				 &realm->inodes_with_caps);
 
 
 
 589			spin_unlock(&realm->inodes_with_caps_lock);
 
 
 
 590		} else {
 591			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 592			       realmino);
 593			WARN_ON(!realm);
 594		}
 595	}
 596
 597	__check_cap_issue(ci, cap, issued);
 598
 599	/*
 600	 * If we are issued caps we don't want, or the mds' wanted
 601	 * value appears to be off, queue a check so we'll release
 602	 * later and/or update the mds wanted value.
 603	 */
 604	actual_wanted = __ceph_caps_wanted(ci);
 605	if ((wanted & ~actual_wanted) ||
 606	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 607		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 608		     ceph_cap_string(issued), ceph_cap_string(wanted),
 609		     ceph_cap_string(actual_wanted));
 610		__cap_delay_requeue(mdsc, ci);
 611	}
 612
 613	if (flags & CEPH_CAP_FLAG_AUTH) {
 614		if (ci->i_auth_cap == NULL ||
 615		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 616			ci->i_auth_cap = cap;
 617			cap->mds_wanted = wanted;
 618		}
 619	} else {
 620		WARN_ON(ci->i_auth_cap == cap);
 621	}
 622
 623	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 624	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 625	     ceph_cap_string(issued|cap->issued), seq, mds);
 626	cap->cap_id = cap_id;
 627	cap->issued = issued;
 628	cap->implemented |= issued;
 629	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 630		cap->mds_wanted = wanted;
 631	else
 632		cap->mds_wanted |= wanted;
 633	cap->seq = seq;
 634	cap->issue_seq = seq;
 635	cap->mseq = mseq;
 636	cap->cap_gen = session->s_cap_gen;
 637
 638	if (fmode >= 0)
 639		__ceph_get_fmode(ci, fmode);
 640}
 641
 642/*
 643 * Return true if cap has not timed out and belongs to the current
 644 * generation of the MDS session (i.e. has not gone 'stale' due to
 645 * us losing touch with the mds).
 646 */
 647static int __cap_is_valid(struct ceph_cap *cap)
 648{
 649	unsigned long ttl;
 650	u32 gen;
 651
 652	spin_lock(&cap->session->s_gen_ttl_lock);
 653	gen = cap->session->s_cap_gen;
 654	ttl = cap->session->s_cap_ttl;
 655	spin_unlock(&cap->session->s_gen_ttl_lock);
 656
 657	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 658		dout("__cap_is_valid %p cap %p issued %s "
 659		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 660		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 661		return 0;
 662	}
 663
 664	return 1;
 665}
 666
 667/*
 668 * Return set of valid cap bits issued to us.  Note that caps time
 669 * out, and may be invalidated in bulk if the client session times out
 670 * and session->s_cap_gen is bumped.
 671 */
 672int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 673{
 674	int have = ci->i_snap_caps;
 675	struct ceph_cap *cap;
 676	struct rb_node *p;
 677
 678	if (implemented)
 679		*implemented = 0;
 680	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 681		cap = rb_entry(p, struct ceph_cap, ci_node);
 682		if (!__cap_is_valid(cap))
 683			continue;
 684		dout("__ceph_caps_issued %p cap %p issued %s\n",
 685		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 686		have |= cap->issued;
 687		if (implemented)
 688			*implemented |= cap->implemented;
 689	}
 690	/*
 691	 * exclude caps issued by non-auth MDS, but are been revoking
 692	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 693	 * these caps, but the message is delayed.
 694	 */
 695	if (ci->i_auth_cap) {
 696		cap = ci->i_auth_cap;
 697		have &= ~cap->implemented | cap->issued;
 698	}
 699	return have;
 700}
 701
 702/*
 703 * Get cap bits issued by caps other than @ocap
 704 */
 705int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 706{
 707	int have = ci->i_snap_caps;
 708	struct ceph_cap *cap;
 709	struct rb_node *p;
 710
 711	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 712		cap = rb_entry(p, struct ceph_cap, ci_node);
 713		if (cap == ocap)
 714			continue;
 715		if (!__cap_is_valid(cap))
 716			continue;
 717		have |= cap->issued;
 718	}
 719	return have;
 720}
 721
 722/*
 723 * Move a cap to the end of the LRU (oldest caps at list head, newest
 724 * at list tail).
 725 */
 726static void __touch_cap(struct ceph_cap *cap)
 727{
 728	struct ceph_mds_session *s = cap->session;
 729
 730	spin_lock(&s->s_cap_lock);
 731	if (s->s_cap_iterator == NULL) {
 732		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 733		     s->s_mds);
 734		list_move_tail(&cap->session_caps, &s->s_caps);
 735	} else {
 736		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 737		     &cap->ci->vfs_inode, cap, s->s_mds);
 738	}
 739	spin_unlock(&s->s_cap_lock);
 740}
 741
 742/*
 743 * Check if we hold the given mask.  If so, move the cap(s) to the
 744 * front of their respective LRUs.  (This is the preferred way for
 745 * callers to check for caps they want.)
 746 */
 747int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 748{
 749	struct ceph_cap *cap;
 750	struct rb_node *p;
 751	int have = ci->i_snap_caps;
 752
 753	if ((have & mask) == mask) {
 754		dout("__ceph_caps_issued_mask %p snap issued %s"
 755		     " (mask %s)\n", &ci->vfs_inode,
 756		     ceph_cap_string(have),
 757		     ceph_cap_string(mask));
 758		return 1;
 759	}
 760
 761	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 762		cap = rb_entry(p, struct ceph_cap, ci_node);
 763		if (!__cap_is_valid(cap))
 764			continue;
 765		if ((cap->issued & mask) == mask) {
 766			dout("__ceph_caps_issued_mask %p cap %p issued %s"
 767			     " (mask %s)\n", &ci->vfs_inode, cap,
 768			     ceph_cap_string(cap->issued),
 769			     ceph_cap_string(mask));
 770			if (touch)
 771				__touch_cap(cap);
 772			return 1;
 773		}
 774
 775		/* does a combination of caps satisfy mask? */
 776		have |= cap->issued;
 777		if ((have & mask) == mask) {
 778			dout("__ceph_caps_issued_mask %p combo issued %s"
 779			     " (mask %s)\n", &ci->vfs_inode,
 780			     ceph_cap_string(cap->issued),
 781			     ceph_cap_string(mask));
 782			if (touch) {
 783				struct rb_node *q;
 784
 785				/* touch this + preceding caps */
 786				__touch_cap(cap);
 787				for (q = rb_first(&ci->i_caps); q != p;
 788				     q = rb_next(q)) {
 789					cap = rb_entry(q, struct ceph_cap,
 790						       ci_node);
 791					if (!__cap_is_valid(cap))
 792						continue;
 793					__touch_cap(cap);
 794				}
 795			}
 796			return 1;
 797		}
 798	}
 799
 800	return 0;
 801}
 802
 803/*
 804 * Return true if mask caps are currently being revoked by an MDS.
 805 */
 806int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 807			       struct ceph_cap *ocap, int mask)
 808{
 809	struct ceph_cap *cap;
 810	struct rb_node *p;
 811
 812	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 813		cap = rb_entry(p, struct ceph_cap, ci_node);
 814		if (cap != ocap &&
 815		    (cap->implemented & ~cap->issued & mask))
 816			return 1;
 817	}
 818	return 0;
 819}
 820
 821int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 822{
 823	struct inode *inode = &ci->vfs_inode;
 824	int ret;
 825
 826	spin_lock(&ci->i_ceph_lock);
 827	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 828	spin_unlock(&ci->i_ceph_lock);
 829	dout("ceph_caps_revoking %p %s = %d\n", inode,
 830	     ceph_cap_string(mask), ret);
 831	return ret;
 832}
 833
 834int __ceph_caps_used(struct ceph_inode_info *ci)
 835{
 836	int used = 0;
 837	if (ci->i_pin_ref)
 838		used |= CEPH_CAP_PIN;
 839	if (ci->i_rd_ref)
 840		used |= CEPH_CAP_FILE_RD;
 841	if (ci->i_rdcache_ref ||
 842	    (!S_ISDIR(ci->vfs_inode.i_mode) && /* ignore readdir cache */
 843	     ci->vfs_inode.i_data.nrpages))
 844		used |= CEPH_CAP_FILE_CACHE;
 845	if (ci->i_wr_ref)
 846		used |= CEPH_CAP_FILE_WR;
 847	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 848		used |= CEPH_CAP_FILE_BUFFER;
 849	return used;
 850}
 851
 852/*
 853 * wanted, by virtue of open file modes
 854 */
 855int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 856{
 857	int i, bits = 0;
 858	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
 859		if (ci->i_nr_by_mode[i])
 860			bits |= 1 << i;
 861	}
 862	if (bits == 0)
 863		return 0;
 864	return ceph_caps_for_mode(bits >> 1);
 865}
 866
 867/*
 868 * Return caps we have registered with the MDS(s) as 'wanted'.
 869 */
 870int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
 871{
 872	struct ceph_cap *cap;
 873	struct rb_node *p;
 874	int mds_wanted = 0;
 875
 876	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 877		cap = rb_entry(p, struct ceph_cap, ci_node);
 878		if (!__cap_is_valid(cap))
 879			continue;
 880		if (cap == ci->i_auth_cap)
 881			mds_wanted |= cap->mds_wanted;
 882		else
 883			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
 884	}
 885	return mds_wanted;
 886}
 887
 888/*
 889 * called under i_ceph_lock
 890 */
 
 
 
 
 
 891static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 892{
 893	return !RB_EMPTY_ROOT(&ci->i_caps);
 894}
 895
 896int ceph_is_any_caps(struct inode *inode)
 897{
 898	struct ceph_inode_info *ci = ceph_inode(inode);
 899	int ret;
 900
 901	spin_lock(&ci->i_ceph_lock);
 902	ret = __ceph_is_any_caps(ci);
 903	spin_unlock(&ci->i_ceph_lock);
 904
 905	return ret;
 906}
 907
 908static void drop_inode_snap_realm(struct ceph_inode_info *ci)
 909{
 910	struct ceph_snap_realm *realm = ci->i_snap_realm;
 911	spin_lock(&realm->inodes_with_caps_lock);
 912	list_del_init(&ci->i_snap_realm_item);
 913	ci->i_snap_realm_counter++;
 914	ci->i_snap_realm = NULL;
 
 
 915	spin_unlock(&realm->inodes_with_caps_lock);
 916	ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc,
 917			    realm);
 918}
 919
 920/*
 921 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
 922 *
 923 * caller should hold i_ceph_lock.
 924 * caller will not hold session s_mutex if called from destroy_inode.
 925 */
 926void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
 927{
 928	struct ceph_mds_session *session = cap->session;
 929	struct ceph_inode_info *ci = cap->ci;
 930	struct ceph_mds_client *mdsc =
 931		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
 932	int removed = 0;
 933
 934	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
 935
 
 
 
 
 
 936	/* remove from session list */
 937	spin_lock(&session->s_cap_lock);
 938	if (session->s_cap_iterator == cap) {
 939		/* not yet, we are iterating over this very cap */
 940		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
 941		     cap, cap->session);
 942	} else {
 943		list_del_init(&cap->session_caps);
 944		session->s_nr_caps--;
 945		cap->session = NULL;
 946		removed = 1;
 947	}
 948	/* protect backpointer with s_cap_lock: see iterate_session_caps */
 949	cap->ci = NULL;
 950
 951	/*
 952	 * s_cap_reconnect is protected by s_cap_lock. no one changes
 953	 * s_cap_gen while session is in the reconnect state.
 954	 */
 955	if (queue_release &&
 956	    (!session->s_cap_reconnect || cap->cap_gen == session->s_cap_gen)) {
 957		cap->queue_release = 1;
 958		if (removed) {
 959			list_add_tail(&cap->session_caps,
 960				      &session->s_cap_releases);
 961			session->s_num_cap_releases++;
 962			removed = 0;
 963		}
 964	} else {
 965		cap->queue_release = 0;
 966	}
 967	cap->cap_ino = ci->i_vino.ino;
 968
 969	spin_unlock(&session->s_cap_lock);
 970
 971	/* remove from inode list */
 972	rb_erase(&cap->ci_node, &ci->i_caps);
 973	if (ci->i_auth_cap == cap)
 974		ci->i_auth_cap = NULL;
 975
 976	if (removed)
 977		ceph_put_cap(mdsc, cap);
 978
 979	/* when reconnect denied, we remove session caps forcibly,
 980	 * i_wr_ref can be non-zero. If there are ongoing write,
 981	 * keep i_snap_realm.
 982	 */
 983	if (!__ceph_is_any_caps(ci) && ci->i_wr_ref == 0 && ci->i_snap_realm)
 984		drop_inode_snap_realm(ci);
 985
 986	if (!__ceph_is_any_real_caps(ci))
 987		__cap_delay_cancel(mdsc, ci);
 988}
 989
 990struct cap_msg_args {
 991	struct ceph_mds_session	*session;
 992	u64			ino, cid, follows;
 993	u64			flush_tid, oldest_flush_tid, size, max_size;
 994	u64			xattr_version;
 
 995	struct ceph_buffer	*xattr_buf;
 996	struct timespec		atime, mtime, ctime;
 997	int			op, caps, wanted, dirty;
 998	u32			seq, issue_seq, mseq, time_warp_seq;
 999	u32			flags;
1000	kuid_t			uid;
1001	kgid_t			gid;
1002	umode_t			mode;
1003	bool			inline_data;
1004};
1005
1006/*
1007 * Build and send a cap message to the given MDS.
1008 *
1009 * Caller should be holding s_mutex.
1010 */
1011static int send_cap_msg(struct cap_msg_args *arg)
1012{
1013	struct ceph_mds_caps *fc;
1014	struct ceph_msg *msg;
1015	void *p;
1016	size_t extra_len;
1017	struct timespec zerotime = {0};
1018
1019	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
1020	     " seq %u/%u tid %llu/%llu mseq %u follows %lld size %llu/%llu"
1021	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(arg->op),
1022	     arg->cid, arg->ino, ceph_cap_string(arg->caps),
1023	     ceph_cap_string(arg->wanted), ceph_cap_string(arg->dirty),
1024	     arg->seq, arg->issue_seq, arg->flush_tid, arg->oldest_flush_tid,
1025	     arg->mseq, arg->follows, arg->size, arg->max_size,
1026	     arg->xattr_version,
1027	     arg->xattr_buf ? (int)arg->xattr_buf->vec.iov_len : 0);
1028
1029	/* flock buffer size + inline version + inline data size +
1030	 * osd_epoch_barrier + oldest_flush_tid */
1031	extra_len = 4 + 8 + 4 + 4 + 8 + 4 + 4 + 4 + 8 + 8 + 4;
1032	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc) + extra_len,
1033			   GFP_NOFS, false);
1034	if (!msg)
1035		return -ENOMEM;
1036
1037	msg->hdr.version = cpu_to_le16(10);
1038	msg->hdr.tid = cpu_to_le64(arg->flush_tid);
1039
1040	fc = msg->front.iov_base;
1041	memset(fc, 0, sizeof(*fc));
1042
1043	fc->cap_id = cpu_to_le64(arg->cid);
1044	fc->op = cpu_to_le32(arg->op);
1045	fc->seq = cpu_to_le32(arg->seq);
1046	fc->issue_seq = cpu_to_le32(arg->issue_seq);
1047	fc->migrate_seq = cpu_to_le32(arg->mseq);
1048	fc->caps = cpu_to_le32(arg->caps);
1049	fc->wanted = cpu_to_le32(arg->wanted);
1050	fc->dirty = cpu_to_le32(arg->dirty);
1051	fc->ino = cpu_to_le64(arg->ino);
1052	fc->snap_follows = cpu_to_le64(arg->follows);
1053
1054	fc->size = cpu_to_le64(arg->size);
1055	fc->max_size = cpu_to_le64(arg->max_size);
1056	ceph_encode_timespec(&fc->mtime, &arg->mtime);
1057	ceph_encode_timespec(&fc->atime, &arg->atime);
1058	ceph_encode_timespec(&fc->ctime, &arg->ctime);
1059	fc->time_warp_seq = cpu_to_le32(arg->time_warp_seq);
1060
1061	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, arg->uid));
1062	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, arg->gid));
1063	fc->mode = cpu_to_le32(arg->mode);
1064
1065	fc->xattr_version = cpu_to_le64(arg->xattr_version);
1066	if (arg->xattr_buf) {
1067		msg->middle = ceph_buffer_get(arg->xattr_buf);
1068		fc->xattr_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1069		msg->hdr.middle_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1070	}
1071
1072	p = fc + 1;
1073	/* flock buffer size (version 2) */
1074	ceph_encode_32(&p, 0);
1075	/* inline version (version 4) */
1076	ceph_encode_64(&p, arg->inline_data ? 0 : CEPH_INLINE_NONE);
1077	/* inline data size */
1078	ceph_encode_32(&p, 0);
1079	/* osd_epoch_barrier (version 5) */
1080	ceph_encode_32(&p, 0);
 
 
 
 
1081	/* oldest_flush_tid (version 6) */
1082	ceph_encode_64(&p, arg->oldest_flush_tid);
1083
1084	/*
1085	 * caller_uid/caller_gid (version 7)
1086	 *
1087	 * Currently, we don't properly track which caller dirtied the caps
1088	 * last, and force a flush of them when there is a conflict. For now,
1089	 * just set this to 0:0, to emulate how the MDS has worked up to now.
1090	 */
1091	ceph_encode_32(&p, 0);
1092	ceph_encode_32(&p, 0);
1093
1094	/* pool namespace (version 8) (mds always ignores this) */
1095	ceph_encode_32(&p, 0);
1096
1097	/*
1098	 * btime and change_attr (version 9)
1099	 *
1100	 * We just zero these out for now, as the MDS ignores them unless
1101	 * the requisite feature flags are set (which we don't do yet).
1102	 */
1103	ceph_encode_timespec(p, &zerotime);
1104	p += sizeof(struct ceph_timespec);
1105	ceph_encode_64(&p, 0);
1106
1107	/* Advisory flags (version 10) */
1108	ceph_encode_32(&p, arg->flags);
1109
1110	ceph_con_send(&arg->session->s_con, msg);
1111	return 0;
1112}
1113
1114/*
1115 * Queue cap releases when an inode is dropped from our cache.  Since
1116 * inode is about to be destroyed, there is no need for i_ceph_lock.
1117 */
1118void ceph_queue_caps_release(struct inode *inode)
1119{
1120	struct ceph_inode_info *ci = ceph_inode(inode);
1121	struct rb_node *p;
1122
 
 
 
1123	p = rb_first(&ci->i_caps);
1124	while (p) {
1125		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1126		p = rb_next(p);
1127		__ceph_remove_cap(cap, true);
1128	}
 
1129}
1130
1131/*
1132 * Send a cap msg on the given inode.  Update our caps state, then
1133 * drop i_ceph_lock and send the message.
1134 *
1135 * Make note of max_size reported/requested from mds, revoked caps
1136 * that have now been implemented.
1137 *
1138 * Make half-hearted attempt ot to invalidate page cache if we are
1139 * dropping RDCACHE.  Note that this will leave behind locked pages
1140 * that we'll then need to deal with elsewhere.
1141 *
1142 * Return non-zero if delayed release, or we experienced an error
1143 * such that the caller should requeue + retry later.
1144 *
1145 * called with i_ceph_lock, then drops it.
1146 * caller should hold snap_rwsem (read), s_mutex.
1147 */
1148static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1149		      int op, bool sync, int used, int want, int retain,
1150		      int flushing, u64 flush_tid, u64 oldest_flush_tid)
1151	__releases(cap->ci->i_ceph_lock)
1152{
1153	struct ceph_inode_info *ci = cap->ci;
1154	struct inode *inode = &ci->vfs_inode;
 
1155	struct cap_msg_args arg;
1156	int held, revoking, dropping;
1157	int wake = 0;
1158	int delayed = 0;
1159	int ret;
1160
1161	held = cap->issued | cap->implemented;
1162	revoking = cap->implemented & ~cap->issued;
1163	retain &= ~revoking;
1164	dropping = cap->issued & ~retain;
1165
1166	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1167	     inode, cap, cap->session,
1168	     ceph_cap_string(held), ceph_cap_string(held & retain),
1169	     ceph_cap_string(revoking));
1170	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1171
1172	arg.session = cap->session;
1173
1174	/* don't release wanted unless we've waited a bit. */
1175	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1176	    time_before(jiffies, ci->i_hold_caps_min)) {
1177		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1178		     ceph_cap_string(cap->issued),
1179		     ceph_cap_string(cap->issued & retain),
1180		     ceph_cap_string(cap->mds_wanted),
1181		     ceph_cap_string(want));
1182		want |= cap->mds_wanted;
1183		retain |= cap->issued;
1184		delayed = 1;
1185	}
1186	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
 
 
 
 
 
 
 
1187
1188	cap->issued &= retain;  /* drop bits we don't want */
1189	if (cap->implemented & ~cap->issued) {
1190		/*
1191		 * Wake up any waiters on wanted -> needed transition.
1192		 * This is due to the weird transition from buffered
1193		 * to sync IO... we need to flush dirty pages _before_
1194		 * allowing sync writes to avoid reordering.
1195		 */
1196		wake = 1;
1197	}
1198	cap->implemented &= cap->issued | used;
1199	cap->mds_wanted = want;
1200
1201	arg.ino = ceph_vino(inode).ino;
1202	arg.cid = cap->cap_id;
1203	arg.follows = flushing ? ci->i_head_snapc->seq : 0;
1204	arg.flush_tid = flush_tid;
1205	arg.oldest_flush_tid = oldest_flush_tid;
1206
1207	arg.size = inode->i_size;
1208	ci->i_reported_size = arg.size;
1209	arg.max_size = ci->i_wanted_max_size;
1210	ci->i_requested_max_size = arg.max_size;
1211
1212	if (flushing & CEPH_CAP_XATTR_EXCL) {
1213		__ceph_build_xattrs_blob(ci);
1214		arg.xattr_version = ci->i_xattrs.version;
1215		arg.xattr_buf = ci->i_xattrs.blob;
1216	} else {
1217		arg.xattr_buf = NULL;
1218	}
1219
1220	arg.mtime = inode->i_mtime;
1221	arg.atime = inode->i_atime;
1222	arg.ctime = inode->i_ctime;
 
 
1223
1224	arg.op = op;
1225	arg.caps = cap->implemented;
1226	arg.wanted = want;
1227	arg.dirty = flushing;
1228
1229	arg.seq = cap->seq;
1230	arg.issue_seq = cap->issue_seq;
1231	arg.mseq = cap->mseq;
1232	arg.time_warp_seq = ci->i_time_warp_seq;
1233
1234	arg.uid = inode->i_uid;
1235	arg.gid = inode->i_gid;
1236	arg.mode = inode->i_mode;
1237
1238	arg.inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1239	arg.flags = 0;
1240	if (sync)
1241		arg.flags |= CEPH_CLIENT_CAPS_SYNC;
 
 
 
 
 
 
 
 
 
 
1242
1243	spin_unlock(&ci->i_ceph_lock);
1244
 
 
1245	ret = send_cap_msg(&arg);
1246	if (ret < 0) {
1247		dout("error sending cap msg, must requeue %p\n", inode);
1248		delayed = 1;
1249	}
1250
1251	if (wake)
1252		wake_up_all(&ci->i_cap_wq);
1253
1254	return delayed;
1255}
1256
1257static inline int __send_flush_snap(struct inode *inode,
1258				    struct ceph_mds_session *session,
1259				    struct ceph_cap_snap *capsnap,
1260				    u32 mseq, u64 oldest_flush_tid)
1261{
1262	struct cap_msg_args	arg;
1263
1264	arg.session = session;
1265	arg.ino = ceph_vino(inode).ino;
1266	arg.cid = 0;
1267	arg.follows = capsnap->follows;
1268	arg.flush_tid = capsnap->cap_flush.tid;
1269	arg.oldest_flush_tid = oldest_flush_tid;
1270
1271	arg.size = capsnap->size;
1272	arg.max_size = 0;
1273	arg.xattr_version = capsnap->xattr_version;
1274	arg.xattr_buf = capsnap->xattr_blob;
1275
1276	arg.atime = capsnap->atime;
1277	arg.mtime = capsnap->mtime;
1278	arg.ctime = capsnap->ctime;
 
 
1279
1280	arg.op = CEPH_CAP_OP_FLUSHSNAP;
1281	arg.caps = capsnap->issued;
1282	arg.wanted = 0;
1283	arg.dirty = capsnap->dirty;
1284
1285	arg.seq = 0;
1286	arg.issue_seq = 0;
1287	arg.mseq = mseq;
1288	arg.time_warp_seq = capsnap->time_warp_seq;
1289
1290	arg.uid = capsnap->uid;
1291	arg.gid = capsnap->gid;
1292	arg.mode = capsnap->mode;
1293
1294	arg.inline_data = capsnap->inline_data;
1295	arg.flags = 0;
1296
1297	return send_cap_msg(&arg);
1298}
1299
1300/*
1301 * When a snapshot is taken, clients accumulate dirty metadata on
1302 * inodes with capabilities in ceph_cap_snaps to describe the file
1303 * state at the time the snapshot was taken.  This must be flushed
1304 * asynchronously back to the MDS once sync writes complete and dirty
1305 * data is written out.
1306 *
1307 * Called under i_ceph_lock.  Takes s_mutex as needed.
1308 */
1309static void __ceph_flush_snaps(struct ceph_inode_info *ci,
1310			       struct ceph_mds_session *session)
1311		__releases(ci->i_ceph_lock)
1312		__acquires(ci->i_ceph_lock)
1313{
1314	struct inode *inode = &ci->vfs_inode;
1315	struct ceph_mds_client *mdsc = session->s_mdsc;
1316	struct ceph_cap_snap *capsnap;
1317	u64 oldest_flush_tid = 0;
1318	u64 first_tid = 1, last_tid = 0;
1319
1320	dout("__flush_snaps %p session %p\n", inode, session);
1321
1322	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1323		/*
1324		 * we need to wait for sync writes to complete and for dirty
1325		 * pages to be written out.
1326		 */
1327		if (capsnap->dirty_pages || capsnap->writing)
1328			break;
1329
1330		/* should be removed by ceph_try_drop_cap_snap() */
1331		BUG_ON(!capsnap->need_flush);
1332
1333		/* only flush each capsnap once */
1334		if (capsnap->cap_flush.tid > 0) {
1335			dout(" already flushed %p, skipping\n", capsnap);
1336			continue;
1337		}
1338
1339		spin_lock(&mdsc->cap_dirty_lock);
1340		capsnap->cap_flush.tid = ++mdsc->last_cap_flush_tid;
1341		list_add_tail(&capsnap->cap_flush.g_list,
1342			      &mdsc->cap_flush_list);
1343		if (oldest_flush_tid == 0)
1344			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1345		if (list_empty(&ci->i_flushing_item)) {
1346			list_add_tail(&ci->i_flushing_item,
1347				      &session->s_cap_flushing);
1348		}
1349		spin_unlock(&mdsc->cap_dirty_lock);
1350
1351		list_add_tail(&capsnap->cap_flush.i_list,
1352			      &ci->i_cap_flush_list);
1353
1354		if (first_tid == 1)
1355			first_tid = capsnap->cap_flush.tid;
1356		last_tid = capsnap->cap_flush.tid;
1357	}
1358
1359	ci->i_ceph_flags &= ~CEPH_I_FLUSH_SNAPS;
1360
1361	while (first_tid <= last_tid) {
1362		struct ceph_cap *cap = ci->i_auth_cap;
1363		struct ceph_cap_flush *cf;
1364		int ret;
1365
1366		if (!(cap && cap->session == session)) {
1367			dout("__flush_snaps %p auth cap %p not mds%d, "
1368			     "stop\n", inode, cap, session->s_mds);
1369			break;
1370		}
1371
1372		ret = -ENOENT;
1373		list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
1374			if (cf->tid >= first_tid) {
1375				ret = 0;
1376				break;
1377			}
1378		}
1379		if (ret < 0)
1380			break;
1381
1382		first_tid = cf->tid + 1;
1383
1384		capsnap = container_of(cf, struct ceph_cap_snap, cap_flush);
1385		atomic_inc(&capsnap->nref);
1386		spin_unlock(&ci->i_ceph_lock);
1387
1388		dout("__flush_snaps %p capsnap %p tid %llu %s\n",
1389		     inode, capsnap, cf->tid, ceph_cap_string(capsnap->dirty));
1390
1391		ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
1392					oldest_flush_tid);
1393		if (ret < 0) {
1394			pr_err("__flush_snaps: error sending cap flushsnap, "
1395			       "ino (%llx.%llx) tid %llu follows %llu\n",
1396				ceph_vinop(inode), cf->tid, capsnap->follows);
1397		}
1398
1399		ceph_put_cap_snap(capsnap);
1400		spin_lock(&ci->i_ceph_lock);
1401	}
1402}
1403
1404void ceph_flush_snaps(struct ceph_inode_info *ci,
1405		      struct ceph_mds_session **psession)
1406{
1407	struct inode *inode = &ci->vfs_inode;
1408	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1409	struct ceph_mds_session *session = NULL;
1410	int mds;
1411
1412	dout("ceph_flush_snaps %p\n", inode);
1413	if (psession)
1414		session = *psession;
1415retry:
1416	spin_lock(&ci->i_ceph_lock);
1417	if (!(ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)) {
1418		dout(" no capsnap needs flush, doing nothing\n");
1419		goto out;
1420	}
1421	if (!ci->i_auth_cap) {
1422		dout(" no auth cap (migrating?), doing nothing\n");
1423		goto out;
1424	}
1425
1426	mds = ci->i_auth_cap->session->s_mds;
1427	if (session && session->s_mds != mds) {
1428		dout(" oops, wrong session %p mutex\n", session);
1429		mutex_unlock(&session->s_mutex);
1430		ceph_put_mds_session(session);
1431		session = NULL;
1432	}
1433	if (!session) {
1434		spin_unlock(&ci->i_ceph_lock);
1435		mutex_lock(&mdsc->mutex);
1436		session = __ceph_lookup_mds_session(mdsc, mds);
1437		mutex_unlock(&mdsc->mutex);
1438		if (session) {
1439			dout(" inverting session/ino locks on %p\n", session);
1440			mutex_lock(&session->s_mutex);
1441		}
1442		goto retry;
1443	}
1444
 
 
 
 
1445	__ceph_flush_snaps(ci, session);
1446out:
1447	spin_unlock(&ci->i_ceph_lock);
1448
1449	if (psession) {
1450		*psession = session;
1451	} else {
1452		mutex_unlock(&session->s_mutex);
1453		ceph_put_mds_session(session);
1454	}
1455	/* we flushed them all; remove this inode from the queue */
1456	spin_lock(&mdsc->snap_flush_lock);
1457	list_del_init(&ci->i_snap_flush_item);
1458	spin_unlock(&mdsc->snap_flush_lock);
1459}
1460
1461/*
1462 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1463 * Caller is then responsible for calling __mark_inode_dirty with the
1464 * returned flags value.
1465 */
1466int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask,
1467			   struct ceph_cap_flush **pcf)
1468{
1469	struct ceph_mds_client *mdsc =
1470		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1471	struct inode *inode = &ci->vfs_inode;
1472	int was = ci->i_dirty_caps;
1473	int dirty = 0;
1474
1475	if (!ci->i_auth_cap) {
1476		pr_warn("__mark_dirty_caps %p %llx mask %s, "
1477			"but no auth cap (session was closed?)\n",
1478			inode, ceph_ino(inode), ceph_cap_string(mask));
1479		return 0;
1480	}
1481
1482	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1483	     ceph_cap_string(mask), ceph_cap_string(was),
1484	     ceph_cap_string(was | mask));
1485	ci->i_dirty_caps |= mask;
1486	if (was == 0) {
1487		WARN_ON_ONCE(ci->i_prealloc_cap_flush);
1488		swap(ci->i_prealloc_cap_flush, *pcf);
1489
1490		if (!ci->i_head_snapc) {
1491			WARN_ON_ONCE(!rwsem_is_locked(&mdsc->snap_rwsem));
1492			ci->i_head_snapc = ceph_get_snap_context(
1493				ci->i_snap_realm->cached_context);
1494		}
1495		dout(" inode %p now dirty snapc %p auth cap %p\n",
1496		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
1497		BUG_ON(!list_empty(&ci->i_dirty_item));
1498		spin_lock(&mdsc->cap_dirty_lock);
1499		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1500		spin_unlock(&mdsc->cap_dirty_lock);
1501		if (ci->i_flushing_caps == 0) {
1502			ihold(inode);
1503			dirty |= I_DIRTY_SYNC;
1504		}
1505	} else {
1506		WARN_ON_ONCE(!ci->i_prealloc_cap_flush);
1507	}
1508	BUG_ON(list_empty(&ci->i_dirty_item));
1509	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1510	    (mask & CEPH_CAP_FILE_BUFFER))
1511		dirty |= I_DIRTY_DATASYNC;
1512	__cap_delay_requeue(mdsc, ci);
1513	return dirty;
1514}
1515
1516struct ceph_cap_flush *ceph_alloc_cap_flush(void)
1517{
1518	return kmem_cache_alloc(ceph_cap_flush_cachep, GFP_KERNEL);
1519}
1520
1521void ceph_free_cap_flush(struct ceph_cap_flush *cf)
1522{
1523	if (cf)
1524		kmem_cache_free(ceph_cap_flush_cachep, cf);
1525}
1526
1527static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc)
1528{
1529	if (!list_empty(&mdsc->cap_flush_list)) {
1530		struct ceph_cap_flush *cf =
1531			list_first_entry(&mdsc->cap_flush_list,
1532					 struct ceph_cap_flush, g_list);
1533		return cf->tid;
1534	}
1535	return 0;
1536}
1537
1538/*
1539 * Remove cap_flush from the mdsc's or inode's flushing cap list.
1540 * Return true if caller needs to wake up flush waiters.
1541 */
1542static bool __finish_cap_flush(struct ceph_mds_client *mdsc,
1543			       struct ceph_inode_info *ci,
1544			       struct ceph_cap_flush *cf)
1545{
1546	struct ceph_cap_flush *prev;
1547	bool wake = cf->wake;
1548	if (mdsc) {
1549		/* are there older pending cap flushes? */
1550		if (wake && cf->g_list.prev != &mdsc->cap_flush_list) {
1551			prev = list_prev_entry(cf, g_list);
1552			prev->wake = true;
1553			wake = false;
1554		}
1555		list_del(&cf->g_list);
1556	} else if (ci) {
1557		if (wake && cf->i_list.prev != &ci->i_cap_flush_list) {
1558			prev = list_prev_entry(cf, i_list);
1559			prev->wake = true;
1560			wake = false;
1561		}
1562		list_del(&cf->i_list);
1563	} else {
1564		BUG_ON(1);
1565	}
1566	return wake;
1567}
1568
1569/*
1570 * Add dirty inode to the flushing list.  Assigned a seq number so we
1571 * can wait for caps to flush without starving.
1572 *
1573 * Called under i_ceph_lock.
1574 */
1575static int __mark_caps_flushing(struct inode *inode,
1576				struct ceph_mds_session *session, bool wake,
1577				u64 *flush_tid, u64 *oldest_flush_tid)
1578{
1579	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1580	struct ceph_inode_info *ci = ceph_inode(inode);
1581	struct ceph_cap_flush *cf = NULL;
1582	int flushing;
1583
1584	BUG_ON(ci->i_dirty_caps == 0);
1585	BUG_ON(list_empty(&ci->i_dirty_item));
1586	BUG_ON(!ci->i_prealloc_cap_flush);
1587
1588	flushing = ci->i_dirty_caps;
1589	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1590	     ceph_cap_string(flushing),
1591	     ceph_cap_string(ci->i_flushing_caps),
1592	     ceph_cap_string(ci->i_flushing_caps | flushing));
1593	ci->i_flushing_caps |= flushing;
1594	ci->i_dirty_caps = 0;
1595	dout(" inode %p now !dirty\n", inode);
1596
1597	swap(cf, ci->i_prealloc_cap_flush);
1598	cf->caps = flushing;
1599	cf->wake = wake;
1600
1601	spin_lock(&mdsc->cap_dirty_lock);
1602	list_del_init(&ci->i_dirty_item);
1603
1604	cf->tid = ++mdsc->last_cap_flush_tid;
1605	list_add_tail(&cf->g_list, &mdsc->cap_flush_list);
1606	*oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1607
1608	if (list_empty(&ci->i_flushing_item)) {
1609		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1610		mdsc->num_cap_flushing++;
1611	}
1612	spin_unlock(&mdsc->cap_dirty_lock);
1613
1614	list_add_tail(&cf->i_list, &ci->i_cap_flush_list);
1615
1616	*flush_tid = cf->tid;
1617	return flushing;
1618}
1619
1620/*
1621 * try to invalidate mapping pages without blocking.
1622 */
1623static int try_nonblocking_invalidate(struct inode *inode)
1624{
1625	struct ceph_inode_info *ci = ceph_inode(inode);
1626	u32 invalidating_gen = ci->i_rdcache_gen;
1627
1628	spin_unlock(&ci->i_ceph_lock);
1629	invalidate_mapping_pages(&inode->i_data, 0, -1);
1630	spin_lock(&ci->i_ceph_lock);
1631
1632	if (inode->i_data.nrpages == 0 &&
1633	    invalidating_gen == ci->i_rdcache_gen) {
1634		/* success. */
1635		dout("try_nonblocking_invalidate %p success\n", inode);
1636		/* save any racing async invalidate some trouble */
1637		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1638		return 0;
1639	}
1640	dout("try_nonblocking_invalidate %p failed\n", inode);
1641	return -1;
1642}
1643
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1644/*
1645 * Swiss army knife function to examine currently used and wanted
1646 * versus held caps.  Release, flush, ack revoked caps to mds as
1647 * appropriate.
1648 *
1649 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1650 *    cap release further.
1651 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1652 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1653 *    further delay.
1654 */
1655void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1656		     struct ceph_mds_session *session)
1657{
1658	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1659	struct ceph_mds_client *mdsc = fsc->mdsc;
1660	struct inode *inode = &ci->vfs_inode;
1661	struct ceph_cap *cap;
1662	u64 flush_tid, oldest_flush_tid;
1663	int file_wanted, used, cap_used;
1664	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1665	int issued, implemented, want, retain, revoking, flushing = 0;
1666	int mds = -1;   /* keep track of how far we've gone through i_caps list
1667			   to avoid an infinite loop on retry */
1668	struct rb_node *p;
1669	int delayed = 0, sent = 0, num;
1670	bool is_delayed = flags & CHECK_CAPS_NODELAY;
1671	bool queue_invalidate = false;
1672	bool force_requeue = false;
1673	bool tried_invalidate = false;
1674
1675	/* if we are unmounting, flush any unused caps immediately. */
1676	if (mdsc->stopping)
1677		is_delayed = 1;
1678
1679	spin_lock(&ci->i_ceph_lock);
1680
1681	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1682		flags |= CHECK_CAPS_FLUSH;
1683
 
 
 
 
1684	goto retry_locked;
1685retry:
1686	spin_lock(&ci->i_ceph_lock);
1687retry_locked:
1688	file_wanted = __ceph_caps_file_wanted(ci);
1689	used = __ceph_caps_used(ci);
1690	issued = __ceph_caps_issued(ci, &implemented);
1691	revoking = implemented & ~issued;
1692
1693	want = file_wanted;
1694	retain = file_wanted | used | CEPH_CAP_PIN;
1695	if (!mdsc->stopping && inode->i_nlink > 0) {
1696		if (file_wanted) {
1697			retain |= CEPH_CAP_ANY;       /* be greedy */
1698		} else if (S_ISDIR(inode->i_mode) &&
1699			   (issued & CEPH_CAP_FILE_SHARED) &&
1700			    __ceph_dir_is_complete(ci)) {
1701			/*
1702			 * If a directory is complete, we want to keep
1703			 * the exclusive cap. So that MDS does not end up
1704			 * revoking the shared cap on every create/unlink
1705			 * operation.
1706			 */
1707			want = CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
 
 
 
1708			retain |= want;
1709		} else {
1710
1711			retain |= CEPH_CAP_ANY_SHARED;
1712			/*
1713			 * keep RD only if we didn't have the file open RW,
1714			 * because then the mds would revoke it anyway to
1715			 * journal max_size=0.
1716			 */
1717			if (ci->i_max_size == 0)
1718				retain |= CEPH_CAP_ANY_RD;
1719		}
1720	}
1721
1722	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1723	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1724	     ceph_cap_string(file_wanted),
1725	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1726	     ceph_cap_string(ci->i_flushing_caps),
1727	     ceph_cap_string(issued), ceph_cap_string(revoking),
1728	     ceph_cap_string(retain),
1729	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1730	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1731	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1732
1733	/*
1734	 * If we no longer need to hold onto old our caps, and we may
1735	 * have cached pages, but don't want them, then try to invalidate.
1736	 * If we fail, it's because pages are locked.... try again later.
1737	 */
1738	if ((!is_delayed || mdsc->stopping) &&
1739	    !S_ISDIR(inode->i_mode) &&		/* ignore readdir cache */
1740	    !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
1741	    inode->i_data.nrpages &&		/* have cached pages */
1742	    (revoking & (CEPH_CAP_FILE_CACHE|
1743			 CEPH_CAP_FILE_LAZYIO)) && /*  or revoking cache */
1744	    !tried_invalidate) {
1745		dout("check_caps trying to invalidate on %p\n", inode);
1746		if (try_nonblocking_invalidate(inode) < 0) {
1747			if (revoking & (CEPH_CAP_FILE_CACHE|
1748					CEPH_CAP_FILE_LAZYIO)) {
1749				dout("check_caps queuing invalidate\n");
1750				queue_invalidate = true;
1751				ci->i_rdcache_revoking = ci->i_rdcache_gen;
1752			} else {
1753				dout("check_caps failed to invalidate pages\n");
1754				/* we failed to invalidate pages.  check these
1755				   caps again later. */
1756				force_requeue = true;
1757				__cap_set_timeouts(mdsc, ci);
1758			}
1759		}
1760		tried_invalidate = true;
1761		goto retry_locked;
1762	}
1763
1764	num = 0;
1765	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1766		cap = rb_entry(p, struct ceph_cap, ci_node);
1767		num++;
1768
1769		/* avoid looping forever */
1770		if (mds >= cap->mds ||
1771		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1772			continue;
1773
1774		/* NOTE: no side-effects allowed, until we take s_mutex */
1775
1776		cap_used = used;
1777		if (ci->i_auth_cap && cap != ci->i_auth_cap)
1778			cap_used &= ~ci->i_auth_cap->issued;
1779
1780		revoking = cap->implemented & ~cap->issued;
1781		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
1782		     cap->mds, cap, ceph_cap_string(cap_used),
1783		     ceph_cap_string(cap->issued),
1784		     ceph_cap_string(cap->implemented),
1785		     ceph_cap_string(revoking));
1786
1787		if (cap == ci->i_auth_cap &&
1788		    (cap->issued & CEPH_CAP_FILE_WR)) {
1789			/* request larger max_size from MDS? */
1790			if (ci->i_wanted_max_size > ci->i_max_size &&
1791			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1792				dout("requesting new max_size\n");
1793				goto ack;
1794			}
1795
1796			/* approaching file_max? */
1797			if ((inode->i_size << 1) >= ci->i_max_size &&
1798			    (ci->i_reported_size << 1) < ci->i_max_size) {
1799				dout("i_size approaching max_size\n");
1800				goto ack;
1801			}
1802		}
1803		/* flush anything dirty? */
1804		if (cap == ci->i_auth_cap) {
1805			if ((flags & CHECK_CAPS_FLUSH) && ci->i_dirty_caps) {
1806				dout("flushing dirty caps\n");
1807				goto ack;
1808			}
1809			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS) {
1810				dout("flushing snap caps\n");
1811				goto ack;
1812			}
1813		}
1814
1815		/* completed revocation? going down and there are no caps? */
1816		if (revoking && (revoking & cap_used) == 0) {
1817			dout("completed revocation of %s\n",
1818			     ceph_cap_string(cap->implemented & ~cap->issued));
1819			goto ack;
1820		}
1821
1822		/* want more caps from mds? */
1823		if (want & ~(cap->mds_wanted | cap->issued))
1824			goto ack;
1825
1826		/* things we might delay */
1827		if ((cap->issued & ~retain) == 0 &&
1828		    cap->mds_wanted == want)
1829			continue;     /* nope, all good */
1830
1831		if (is_delayed)
1832			goto ack;
1833
1834		/* delay? */
1835		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1836		    time_before(jiffies, ci->i_hold_caps_max)) {
1837			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1838			     ceph_cap_string(cap->issued),
1839			     ceph_cap_string(cap->issued & retain),
1840			     ceph_cap_string(cap->mds_wanted),
1841			     ceph_cap_string(want));
1842			delayed++;
1843			continue;
1844		}
1845
1846ack:
1847		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1848			dout(" skipping %p I_NOFLUSH set\n", inode);
1849			continue;
1850		}
1851
1852		if (session && session != cap->session) {
1853			dout("oops, wrong session %p mutex\n", session);
1854			mutex_unlock(&session->s_mutex);
1855			session = NULL;
1856		}
1857		if (!session) {
1858			session = cap->session;
1859			if (mutex_trylock(&session->s_mutex) == 0) {
1860				dout("inverting session/ino locks on %p\n",
1861				     session);
1862				spin_unlock(&ci->i_ceph_lock);
1863				if (took_snap_rwsem) {
1864					up_read(&mdsc->snap_rwsem);
1865					took_snap_rwsem = 0;
1866				}
1867				mutex_lock(&session->s_mutex);
1868				goto retry;
1869			}
1870		}
1871
1872		/* kick flushing and flush snaps before sending normal
1873		 * cap message */
1874		if (cap == ci->i_auth_cap &&
1875		    (ci->i_ceph_flags &
1876		     (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS))) {
1877			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
1878				spin_lock(&mdsc->cap_dirty_lock);
1879				oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1880				spin_unlock(&mdsc->cap_dirty_lock);
1881				__kick_flushing_caps(mdsc, session, ci,
1882						     oldest_flush_tid);
1883				ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
1884			}
1885			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
1886				__ceph_flush_snaps(ci, session);
1887
1888			goto retry_locked;
1889		}
1890
1891		/* take snap_rwsem after session mutex */
1892		if (!took_snap_rwsem) {
1893			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1894				dout("inverting snap/in locks on %p\n",
1895				     inode);
1896				spin_unlock(&ci->i_ceph_lock);
1897				down_read(&mdsc->snap_rwsem);
1898				took_snap_rwsem = 1;
1899				goto retry;
1900			}
1901			took_snap_rwsem = 1;
1902		}
1903
1904		if (cap == ci->i_auth_cap && ci->i_dirty_caps) {
1905			flushing = __mark_caps_flushing(inode, session, false,
1906							&flush_tid,
1907							&oldest_flush_tid);
1908		} else {
1909			flushing = 0;
1910			flush_tid = 0;
1911			spin_lock(&mdsc->cap_dirty_lock);
1912			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1913			spin_unlock(&mdsc->cap_dirty_lock);
1914		}
1915
1916		mds = cap->mds;  /* remember mds, so we don't repeat */
1917		sent++;
1918
1919		/* __send_cap drops i_ceph_lock */
1920		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, false,
1921				cap_used, want, retain, flushing,
1922				flush_tid, oldest_flush_tid);
1923		goto retry; /* retake i_ceph_lock and restart our cap scan. */
1924	}
1925
1926	/*
1927	 * Reschedule delayed caps release if we delayed anything,
1928	 * otherwise cancel.
1929	 */
1930	if (delayed && is_delayed)
1931		force_requeue = true;   /* __send_cap delayed release; requeue */
1932	if (!delayed && !is_delayed)
1933		__cap_delay_cancel(mdsc, ci);
1934	else if (!is_delayed || force_requeue)
1935		__cap_delay_requeue(mdsc, ci);
1936
1937	spin_unlock(&ci->i_ceph_lock);
1938
1939	if (queue_invalidate)
1940		ceph_queue_invalidate(inode);
1941
1942	if (session)
1943		mutex_unlock(&session->s_mutex);
1944	if (took_snap_rwsem)
1945		up_read(&mdsc->snap_rwsem);
1946}
1947
1948/*
1949 * Try to flush dirty caps back to the auth mds.
1950 */
1951static int try_flush_caps(struct inode *inode, u64 *ptid)
1952{
1953	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1954	struct ceph_inode_info *ci = ceph_inode(inode);
1955	struct ceph_mds_session *session = NULL;
1956	int flushing = 0;
1957	u64 flush_tid = 0, oldest_flush_tid = 0;
1958
1959retry:
1960	spin_lock(&ci->i_ceph_lock);
1961	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1962		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1963		goto out;
1964	}
1965	if (ci->i_dirty_caps && ci->i_auth_cap) {
1966		struct ceph_cap *cap = ci->i_auth_cap;
1967		int used = __ceph_caps_used(ci);
1968		int want = __ceph_caps_wanted(ci);
1969		int delayed;
1970
1971		if (!session || session != cap->session) {
1972			spin_unlock(&ci->i_ceph_lock);
1973			if (session)
1974				mutex_unlock(&session->s_mutex);
1975			session = cap->session;
1976			mutex_lock(&session->s_mutex);
1977			goto retry;
1978		}
1979		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
 
1980			goto out;
 
 
 
 
 
 
 
 
 
 
1981
1982		flushing = __mark_caps_flushing(inode, session, true,
1983						&flush_tid, &oldest_flush_tid);
 
1984
1985		/* __send_cap drops i_ceph_lock */
1986		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, true,
1987				used, want, (cap->issued | cap->implemented),
1988				flushing, flush_tid, oldest_flush_tid);
 
 
 
1989
1990		if (delayed) {
1991			spin_lock(&ci->i_ceph_lock);
1992			__cap_delay_requeue(mdsc, ci);
1993			spin_unlock(&ci->i_ceph_lock);
1994		}
1995	} else {
1996		if (!list_empty(&ci->i_cap_flush_list)) {
1997			struct ceph_cap_flush *cf =
1998				list_last_entry(&ci->i_cap_flush_list,
1999						struct ceph_cap_flush, i_list);
2000			cf->wake = true;
2001			flush_tid = cf->tid;
2002		}
2003		flushing = ci->i_flushing_caps;
2004		spin_unlock(&ci->i_ceph_lock);
2005	}
2006out:
2007	if (session)
2008		mutex_unlock(&session->s_mutex);
2009
2010	*ptid = flush_tid;
2011	return flushing;
2012}
2013
2014/*
2015 * Return true if we've flushed caps through the given flush_tid.
2016 */
2017static int caps_are_flushed(struct inode *inode, u64 flush_tid)
2018{
2019	struct ceph_inode_info *ci = ceph_inode(inode);
2020	int ret = 1;
2021
2022	spin_lock(&ci->i_ceph_lock);
2023	if (!list_empty(&ci->i_cap_flush_list)) {
2024		struct ceph_cap_flush * cf =
2025			list_first_entry(&ci->i_cap_flush_list,
2026					 struct ceph_cap_flush, i_list);
2027		if (cf->tid <= flush_tid)
2028			ret = 0;
2029	}
2030	spin_unlock(&ci->i_ceph_lock);
2031	return ret;
2032}
2033
2034/*
2035 * wait for any unsafe requests to complete.
2036 */
2037static int unsafe_request_wait(struct inode *inode)
2038{
2039	struct ceph_inode_info *ci = ceph_inode(inode);
2040	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
2041	int ret, err = 0;
2042
2043	spin_lock(&ci->i_unsafe_lock);
2044	if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) {
2045		req1 = list_last_entry(&ci->i_unsafe_dirops,
2046					struct ceph_mds_request,
2047					r_unsafe_dir_item);
2048		ceph_mdsc_get_request(req1);
2049	}
2050	if (!list_empty(&ci->i_unsafe_iops)) {
2051		req2 = list_last_entry(&ci->i_unsafe_iops,
2052					struct ceph_mds_request,
2053					r_unsafe_target_item);
2054		ceph_mdsc_get_request(req2);
2055	}
2056	spin_unlock(&ci->i_unsafe_lock);
2057
2058	dout("unsafe_request_wait %p wait on tid %llu %llu\n",
2059	     inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL);
2060	if (req1) {
2061		ret = !wait_for_completion_timeout(&req1->r_safe_completion,
2062					ceph_timeout_jiffies(req1->r_timeout));
2063		if (ret)
2064			err = -EIO;
2065		ceph_mdsc_put_request(req1);
2066	}
2067	if (req2) {
2068		ret = !wait_for_completion_timeout(&req2->r_safe_completion,
2069					ceph_timeout_jiffies(req2->r_timeout));
2070		if (ret)
2071			err = -EIO;
2072		ceph_mdsc_put_request(req2);
2073	}
2074	return err;
2075}
2076
2077int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2078{
 
2079	struct inode *inode = file->f_mapping->host;
2080	struct ceph_inode_info *ci = ceph_inode(inode);
2081	u64 flush_tid;
2082	int ret;
2083	int dirty;
2084
2085	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
2086
2087	ceph_sync_write_wait(inode);
2088
2089	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
2090	if (ret < 0)
2091		goto out;
2092
2093	if (datasync)
2094		goto out;
2095
2096	inode_lock(inode);
2097
2098	dirty = try_flush_caps(inode, &flush_tid);
2099	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
2100
2101	ret = unsafe_request_wait(inode);
2102
2103	/*
2104	 * only wait on non-file metadata writeback (the mds
2105	 * can recover size and mtime, so we don't need to
2106	 * wait for that)
2107	 */
2108	if (!ret && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
2109		ret = wait_event_interruptible(ci->i_cap_wq,
2110					caps_are_flushed(inode, flush_tid));
2111	}
2112	inode_unlock(inode);
 
 
 
 
 
 
 
 
 
 
 
2113out:
2114	dout("fsync %p%s result=%d\n", inode, datasync ? " datasync" : "", ret);
2115	return ret;
2116}
2117
2118/*
2119 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
2120 * queue inode for flush but don't do so immediately, because we can
2121 * get by with fewer MDS messages if we wait for data writeback to
2122 * complete first.
2123 */
2124int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
2125{
2126	struct ceph_inode_info *ci = ceph_inode(inode);
2127	u64 flush_tid;
2128	int err = 0;
2129	int dirty;
2130	int wait = wbc->sync_mode == WB_SYNC_ALL;
2131
2132	dout("write_inode %p wait=%d\n", inode, wait);
2133	if (wait) {
2134		dirty = try_flush_caps(inode, &flush_tid);
2135		if (dirty)
2136			err = wait_event_interruptible(ci->i_cap_wq,
2137				       caps_are_flushed(inode, flush_tid));
2138	} else {
2139		struct ceph_mds_client *mdsc =
2140			ceph_sb_to_client(inode->i_sb)->mdsc;
2141
2142		spin_lock(&ci->i_ceph_lock);
2143		if (__ceph_caps_dirty(ci))
2144			__cap_delay_requeue_front(mdsc, ci);
2145		spin_unlock(&ci->i_ceph_lock);
2146	}
2147	return err;
2148}
2149
2150static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
2151				 struct ceph_mds_session *session,
2152				 struct ceph_inode_info *ci,
2153				 u64 oldest_flush_tid)
2154	__releases(ci->i_ceph_lock)
2155	__acquires(ci->i_ceph_lock)
2156{
2157	struct inode *inode = &ci->vfs_inode;
2158	struct ceph_cap *cap;
2159	struct ceph_cap_flush *cf;
2160	int ret;
2161	u64 first_tid = 0;
 
 
 
 
 
 
 
 
 
 
2162
2163	list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
2164		if (cf->tid < first_tid)
2165			continue;
2166
2167		cap = ci->i_auth_cap;
2168		if (!(cap && cap->session == session)) {
2169			pr_err("%p auth cap %p not mds%d ???\n",
2170			       inode, cap, session->s_mds);
2171			break;
2172		}
2173
2174		first_tid = cf->tid + 1;
2175
2176		if (cf->caps) {
2177			dout("kick_flushing_caps %p cap %p tid %llu %s\n",
2178			     inode, cap, cf->tid, ceph_cap_string(cf->caps));
2179			ci->i_ceph_flags |= CEPH_I_NODELAY;
 
2180			ret = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2181					  false, __ceph_caps_used(ci),
 
 
2182					  __ceph_caps_wanted(ci),
2183					  cap->issued | cap->implemented,
2184					  cf->caps, cf->tid, oldest_flush_tid);
2185			if (ret) {
2186				pr_err("kick_flushing_caps: error sending "
2187					"cap flush, ino (%llx.%llx) "
2188					"tid %llu flushing %s\n",
2189					ceph_vinop(inode), cf->tid,
2190					ceph_cap_string(cf->caps));
2191			}
2192		} else {
2193			struct ceph_cap_snap *capsnap =
2194					container_of(cf, struct ceph_cap_snap,
2195						    cap_flush);
2196			dout("kick_flushing_caps %p capsnap %p tid %llu %s\n",
2197			     inode, capsnap, cf->tid,
2198			     ceph_cap_string(capsnap->dirty));
2199
2200			atomic_inc(&capsnap->nref);
2201			spin_unlock(&ci->i_ceph_lock);
2202
2203			ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
2204						oldest_flush_tid);
2205			if (ret < 0) {
2206				pr_err("kick_flushing_caps: error sending "
2207					"cap flushsnap, ino (%llx.%llx) "
2208					"tid %llu follows %llu\n",
2209					ceph_vinop(inode), cf->tid,
2210					capsnap->follows);
2211			}
2212
2213			ceph_put_cap_snap(capsnap);
2214		}
2215
2216		spin_lock(&ci->i_ceph_lock);
2217	}
2218}
2219
2220void ceph_early_kick_flushing_caps(struct ceph_mds_client *mdsc,
2221				   struct ceph_mds_session *session)
2222{
2223	struct ceph_inode_info *ci;
2224	struct ceph_cap *cap;
2225	u64 oldest_flush_tid;
2226
2227	dout("early_kick_flushing_caps mds%d\n", session->s_mds);
2228
2229	spin_lock(&mdsc->cap_dirty_lock);
2230	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2231	spin_unlock(&mdsc->cap_dirty_lock);
2232
2233	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2234		spin_lock(&ci->i_ceph_lock);
2235		cap = ci->i_auth_cap;
2236		if (!(cap && cap->session == session)) {
2237			pr_err("%p auth cap %p not mds%d ???\n",
2238				&ci->vfs_inode, cap, session->s_mds);
2239			spin_unlock(&ci->i_ceph_lock);
2240			continue;
2241		}
2242
2243
2244		/*
2245		 * if flushing caps were revoked, we re-send the cap flush
2246		 * in client reconnect stage. This guarantees MDS * processes
2247		 * the cap flush message before issuing the flushing caps to
2248		 * other client.
2249		 */
2250		if ((cap->issued & ci->i_flushing_caps) !=
2251		    ci->i_flushing_caps) {
2252			ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
 
 
 
 
 
2253			__kick_flushing_caps(mdsc, session, ci,
2254					     oldest_flush_tid);
2255		} else {
2256			ci->i_ceph_flags |= CEPH_I_KICK_FLUSH;
2257		}
2258
2259		spin_unlock(&ci->i_ceph_lock);
2260	}
2261}
2262
2263void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
2264			     struct ceph_mds_session *session)
2265{
2266	struct ceph_inode_info *ci;
2267	struct ceph_cap *cap;
2268	u64 oldest_flush_tid;
2269
2270	dout("kick_flushing_caps mds%d\n", session->s_mds);
2271
2272	spin_lock(&mdsc->cap_dirty_lock);
2273	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2274	spin_unlock(&mdsc->cap_dirty_lock);
2275
2276	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2277		spin_lock(&ci->i_ceph_lock);
2278		cap = ci->i_auth_cap;
2279		if (!(cap && cap->session == session)) {
2280			pr_err("%p auth cap %p not mds%d ???\n",
2281				&ci->vfs_inode, cap, session->s_mds);
2282			spin_unlock(&ci->i_ceph_lock);
2283			continue;
2284		}
2285		if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
2286			ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2287			__kick_flushing_caps(mdsc, session, ci,
2288					     oldest_flush_tid);
2289		}
2290		spin_unlock(&ci->i_ceph_lock);
2291	}
2292}
2293
2294static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
2295				     struct ceph_mds_session *session,
2296				     struct inode *inode)
2297	__releases(ci->i_ceph_lock)
2298{
2299	struct ceph_inode_info *ci = ceph_inode(inode);
2300	struct ceph_cap *cap;
2301
2302	cap = ci->i_auth_cap;
2303	dout("kick_flushing_inode_caps %p flushing %s\n", inode,
2304	     ceph_cap_string(ci->i_flushing_caps));
2305
2306	if (!list_empty(&ci->i_cap_flush_list)) {
2307		u64 oldest_flush_tid;
2308		spin_lock(&mdsc->cap_dirty_lock);
2309		list_move_tail(&ci->i_flushing_item,
2310			       &cap->session->s_cap_flushing);
2311		oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2312		spin_unlock(&mdsc->cap_dirty_lock);
2313
2314		ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2315		__kick_flushing_caps(mdsc, session, ci, oldest_flush_tid);
2316		spin_unlock(&ci->i_ceph_lock);
2317	} else {
2318		spin_unlock(&ci->i_ceph_lock);
2319	}
2320}
2321
2322
2323/*
2324 * Take references to capabilities we hold, so that we don't release
2325 * them to the MDS prematurely.
2326 *
2327 * Protected by i_ceph_lock.
2328 */
2329static void __take_cap_refs(struct ceph_inode_info *ci, int got,
2330			    bool snap_rwsem_locked)
2331{
2332	if (got & CEPH_CAP_PIN)
2333		ci->i_pin_ref++;
2334	if (got & CEPH_CAP_FILE_RD)
2335		ci->i_rd_ref++;
2336	if (got & CEPH_CAP_FILE_CACHE)
2337		ci->i_rdcache_ref++;
2338	if (got & CEPH_CAP_FILE_WR) {
2339		if (ci->i_wr_ref == 0 && !ci->i_head_snapc) {
2340			BUG_ON(!snap_rwsem_locked);
2341			ci->i_head_snapc = ceph_get_snap_context(
2342					ci->i_snap_realm->cached_context);
2343		}
2344		ci->i_wr_ref++;
2345	}
2346	if (got & CEPH_CAP_FILE_BUFFER) {
2347		if (ci->i_wb_ref == 0)
2348			ihold(&ci->vfs_inode);
2349		ci->i_wb_ref++;
2350		dout("__take_cap_refs %p wb %d -> %d (?)\n",
2351		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2352	}
2353}
2354
2355/*
2356 * Try to grab cap references.  Specify those refs we @want, and the
2357 * minimal set we @need.  Also include the larger offset we are writing
2358 * to (when applicable), and check against max_size here as well.
2359 * Note that caller is responsible for ensuring max_size increases are
2360 * requested from the MDS.
 
 
 
 
 
2361 */
2362static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
2363			    loff_t endoff, bool nonblock, int *got, int *err)
 
 
 
 
 
2364{
2365	struct inode *inode = &ci->vfs_inode;
2366	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2367	int ret = 0;
2368	int have, implemented;
2369	int file_wanted;
2370	bool snap_rwsem_locked = false;
2371
2372	dout("get_cap_refs %p need %s want %s\n", inode,
2373	     ceph_cap_string(need), ceph_cap_string(want));
2374
2375again:
2376	spin_lock(&ci->i_ceph_lock);
2377
 
 
 
 
 
 
 
2378	/* make sure file is actually open */
2379	file_wanted = __ceph_caps_file_wanted(ci);
2380	if ((file_wanted & need) != need) {
2381		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2382		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2383		*err = -EBADF;
2384		ret = 1;
2385		goto out_unlock;
2386	}
2387
2388	/* finish pending truncate */
2389	while (ci->i_truncate_pending) {
2390		spin_unlock(&ci->i_ceph_lock);
2391		if (snap_rwsem_locked) {
2392			up_read(&mdsc->snap_rwsem);
2393			snap_rwsem_locked = false;
2394		}
2395		__ceph_do_pending_vmtruncate(inode);
2396		spin_lock(&ci->i_ceph_lock);
2397	}
2398
2399	have = __ceph_caps_issued(ci, &implemented);
2400
2401	if (have & need & CEPH_CAP_FILE_WR) {
2402		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2403			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2404			     inode, endoff, ci->i_max_size);
2405			if (endoff > ci->i_requested_max_size) {
2406				*err = -EAGAIN;
2407				ret = 1;
2408			}
2409			goto out_unlock;
2410		}
2411		/*
2412		 * If a sync write is in progress, we must wait, so that we
2413		 * can get a final snapshot value for size+mtime.
2414		 */
2415		if (__ceph_have_pending_cap_snap(ci)) {
2416			dout("get_cap_refs %p cap_snap_pending\n", inode);
2417			goto out_unlock;
2418		}
2419	}
2420
2421	if ((have & need) == need) {
2422		/*
2423		 * Look at (implemented & ~have & not) so that we keep waiting
2424		 * on transition from wanted -> needed caps.  This is needed
2425		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2426		 * going before a prior buffered writeback happens.
2427		 */
2428		int not = want & ~(have & need);
2429		int revoking = implemented & ~have;
2430		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2431		     inode, ceph_cap_string(have), ceph_cap_string(not),
2432		     ceph_cap_string(revoking));
2433		if ((revoking & not) == 0) {
2434			if (!snap_rwsem_locked &&
2435			    !ci->i_head_snapc &&
2436			    (need & CEPH_CAP_FILE_WR)) {
2437				if (!down_read_trylock(&mdsc->snap_rwsem)) {
2438					/*
2439					 * we can not call down_read() when
2440					 * task isn't in TASK_RUNNING state
2441					 */
2442					if (nonblock) {
2443						*err = -EAGAIN;
2444						ret = 1;
2445						goto out_unlock;
2446					}
2447
2448					spin_unlock(&ci->i_ceph_lock);
2449					down_read(&mdsc->snap_rwsem);
2450					snap_rwsem_locked = true;
2451					goto again;
2452				}
2453				snap_rwsem_locked = true;
2454			}
2455			*got = need | (have & want);
2456			if ((need & CEPH_CAP_FILE_RD) &&
2457			    !(*got & CEPH_CAP_FILE_CACHE))
2458				ceph_disable_fscache_readpage(ci);
2459			__take_cap_refs(ci, *got, true);
2460			ret = 1;
2461		}
2462	} else {
2463		int session_readonly = false;
2464		if ((need & CEPH_CAP_FILE_WR) && ci->i_auth_cap) {
2465			struct ceph_mds_session *s = ci->i_auth_cap->session;
2466			spin_lock(&s->s_cap_lock);
2467			session_readonly = s->s_readonly;
2468			spin_unlock(&s->s_cap_lock);
2469		}
2470		if (session_readonly) {
2471			dout("get_cap_refs %p needed %s but mds%d readonly\n",
2472			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
2473			*err = -EROFS;
2474			ret = 1;
2475			goto out_unlock;
2476		}
2477
2478		if (ci->i_ceph_flags & CEPH_I_CAP_DROPPED) {
2479			int mds_wanted;
2480			if (ACCESS_ONCE(mdsc->fsc->mount_state) ==
2481			    CEPH_MOUNT_SHUTDOWN) {
2482				dout("get_cap_refs %p forced umount\n", inode);
2483				*err = -EIO;
2484				ret = 1;
2485				goto out_unlock;
2486			}
2487			mds_wanted = __ceph_caps_mds_wanted(ci);
2488			if ((mds_wanted & need) != need) {
2489				dout("get_cap_refs %p caps were dropped"
2490				     " (session killed?)\n", inode);
2491				*err = -ESTALE;
2492				ret = 1;
2493				goto out_unlock;
2494			}
2495			if ((mds_wanted & file_wanted) ==
2496			    (file_wanted & (CEPH_CAP_FILE_RD|CEPH_CAP_FILE_WR)))
2497				ci->i_ceph_flags &= ~CEPH_I_CAP_DROPPED;
2498		}
2499
2500		dout("get_cap_refs %p have %s needed %s\n", inode,
2501		     ceph_cap_string(have), ceph_cap_string(need));
2502	}
2503out_unlock:
2504	spin_unlock(&ci->i_ceph_lock);
2505	if (snap_rwsem_locked)
2506		up_read(&mdsc->snap_rwsem);
2507
2508	dout("get_cap_refs %p ret %d got %s\n", inode,
2509	     ret, ceph_cap_string(*got));
2510	return ret;
2511}
2512
2513/*
2514 * Check the offset we are writing up to against our current
2515 * max_size.  If necessary, tell the MDS we want to write to
2516 * a larger offset.
2517 */
2518static void check_max_size(struct inode *inode, loff_t endoff)
2519{
2520	struct ceph_inode_info *ci = ceph_inode(inode);
2521	int check = 0;
2522
2523	/* do we need to explicitly request a larger max_size? */
2524	spin_lock(&ci->i_ceph_lock);
2525	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
2526		dout("write %p at large endoff %llu, req max_size\n",
2527		     inode, endoff);
2528		ci->i_wanted_max_size = endoff;
2529	}
2530	/* duplicate ceph_check_caps()'s logic */
2531	if (ci->i_auth_cap &&
2532	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2533	    ci->i_wanted_max_size > ci->i_max_size &&
2534	    ci->i_wanted_max_size > ci->i_requested_max_size)
2535		check = 1;
2536	spin_unlock(&ci->i_ceph_lock);
2537	if (check)
2538		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2539}
2540
2541int ceph_try_get_caps(struct ceph_inode_info *ci, int need, int want, int *got)
 
2542{
2543	int ret, err = 0;
2544
2545	BUG_ON(need & ~CEPH_CAP_FILE_RD);
2546	BUG_ON(want & ~(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO));
2547	ret = ceph_pool_perm_check(ci, need);
2548	if (ret < 0)
2549		return ret;
2550
2551	ret = try_get_cap_refs(ci, need, want, 0, true, got, &err);
2552	if (ret) {
2553		if (err == -EAGAIN) {
2554			ret = 0;
2555		} else if (err < 0) {
2556			ret = err;
2557		}
2558	}
2559	return ret;
2560}
2561
2562/*
2563 * Wait for caps, and take cap references.  If we can't get a WR cap
2564 * due to a small max_size, make sure we check_max_size (and possibly
2565 * ask the mds) so we don't get hung up indefinitely.
2566 */
2567int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
2568		  loff_t endoff, int *got, struct page **pinned_page)
2569{
2570	int _got, ret, err = 0;
 
 
 
 
2571
2572	ret = ceph_pool_perm_check(ci, need);
2573	if (ret < 0)
2574		return ret;
2575
 
 
 
 
2576	while (true) {
2577		if (endoff > 0)
2578			check_max_size(&ci->vfs_inode, endoff);
2579
2580		err = 0;
2581		_got = 0;
2582		ret = try_get_cap_refs(ci, need, want, endoff,
2583				       false, &_got, &err);
2584		if (ret) {
2585			if (err == -EAGAIN)
2586				continue;
2587			if (err < 0)
2588				ret = err;
2589		} else {
2590			DEFINE_WAIT_FUNC(wait, woken_wake_function);
2591			add_wait_queue(&ci->i_cap_wq, &wait);
2592
2593			while (!try_get_cap_refs(ci, need, want, endoff,
2594						 true, &_got, &err)) {
 
2595				if (signal_pending(current)) {
2596					ret = -ERESTARTSYS;
2597					break;
2598				}
2599				wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2600			}
2601
2602			remove_wait_queue(&ci->i_cap_wq, &wait);
2603
2604			if (err == -EAGAIN)
2605				continue;
2606			if (err < 0)
2607				ret = err;
2608		}
 
 
 
 
 
 
 
 
2609		if (ret < 0) {
2610			if (err == -ESTALE) {
2611				/* session was killed, try renew caps */
2612				ret = ceph_renew_caps(&ci->vfs_inode);
2613				if (ret == 0)
2614					continue;
2615			}
2616			return ret;
2617		}
2618
2619		if (ci->i_inline_version != CEPH_INLINE_NONE &&
2620		    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
2621		    i_size_read(&ci->vfs_inode) > 0) {
2622			struct page *page =
2623				find_get_page(ci->vfs_inode.i_mapping, 0);
2624			if (page) {
2625				if (PageUptodate(page)) {
2626					*pinned_page = page;
2627					break;
2628				}
2629				put_page(page);
2630			}
2631			/*
2632			 * drop cap refs first because getattr while
2633			 * holding * caps refs can cause deadlock.
2634			 */
2635			ceph_put_cap_refs(ci, _got);
2636			_got = 0;
2637
2638			/*
2639			 * getattr request will bring inline data into
2640			 * page cache
2641			 */
2642			ret = __ceph_do_getattr(&ci->vfs_inode, NULL,
2643						CEPH_STAT_CAP_INLINE_DATA,
2644						true);
2645			if (ret < 0)
2646				return ret;
2647			continue;
2648		}
2649		break;
2650	}
2651
2652	if ((_got & CEPH_CAP_FILE_RD) && (_got & CEPH_CAP_FILE_CACHE))
2653		ceph_fscache_revalidate_cookie(ci);
2654
2655	*got = _got;
2656	return 0;
2657}
2658
2659/*
2660 * Take cap refs.  Caller must already know we hold at least one ref
2661 * on the caps in question or we don't know this is safe.
2662 */
2663void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2664{
2665	spin_lock(&ci->i_ceph_lock);
2666	__take_cap_refs(ci, caps, false);
2667	spin_unlock(&ci->i_ceph_lock);
2668}
2669
2670
2671/*
2672 * drop cap_snap that is not associated with any snapshot.
2673 * we don't need to send FLUSHSNAP message for it.
2674 */
2675static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
2676				  struct ceph_cap_snap *capsnap)
2677{
2678	if (!capsnap->need_flush &&
2679	    !capsnap->writing && !capsnap->dirty_pages) {
2680		dout("dropping cap_snap %p follows %llu\n",
2681		     capsnap, capsnap->follows);
2682		BUG_ON(capsnap->cap_flush.tid > 0);
2683		ceph_put_snap_context(capsnap->context);
2684		if (!list_is_last(&capsnap->ci_item, &ci->i_cap_snaps))
2685			ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
2686
2687		list_del(&capsnap->ci_item);
2688		ceph_put_cap_snap(capsnap);
2689		return 1;
2690	}
2691	return 0;
2692}
2693
2694/*
2695 * Release cap refs.
2696 *
2697 * If we released the last ref on any given cap, call ceph_check_caps
2698 * to release (or schedule a release).
2699 *
2700 * If we are releasing a WR cap (from a sync write), finalize any affected
2701 * cap_snap, and wake up any waiters.
2702 */
2703void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2704{
2705	struct inode *inode = &ci->vfs_inode;
2706	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2707
2708	spin_lock(&ci->i_ceph_lock);
2709	if (had & CEPH_CAP_PIN)
2710		--ci->i_pin_ref;
2711	if (had & CEPH_CAP_FILE_RD)
2712		if (--ci->i_rd_ref == 0)
2713			last++;
2714	if (had & CEPH_CAP_FILE_CACHE)
2715		if (--ci->i_rdcache_ref == 0)
2716			last++;
2717	if (had & CEPH_CAP_FILE_BUFFER) {
2718		if (--ci->i_wb_ref == 0) {
2719			last++;
2720			put++;
2721		}
2722		dout("put_cap_refs %p wb %d -> %d (?)\n",
2723		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2724	}
2725	if (had & CEPH_CAP_FILE_WR)
2726		if (--ci->i_wr_ref == 0) {
2727			last++;
2728			if (__ceph_have_pending_cap_snap(ci)) {
2729				struct ceph_cap_snap *capsnap =
2730					list_last_entry(&ci->i_cap_snaps,
2731							struct ceph_cap_snap,
2732							ci_item);
2733				capsnap->writing = 0;
2734				if (ceph_try_drop_cap_snap(ci, capsnap))
2735					put++;
2736				else if (__ceph_finish_cap_snap(ci, capsnap))
2737					flushsnaps = 1;
2738				wake = 1;
2739			}
2740			if (ci->i_wrbuffer_ref_head == 0 &&
2741			    ci->i_dirty_caps == 0 &&
2742			    ci->i_flushing_caps == 0) {
2743				BUG_ON(!ci->i_head_snapc);
2744				ceph_put_snap_context(ci->i_head_snapc);
2745				ci->i_head_snapc = NULL;
2746			}
2747			/* see comment in __ceph_remove_cap() */
2748			if (!__ceph_is_any_caps(ci) && ci->i_snap_realm)
2749				drop_inode_snap_realm(ci);
2750		}
2751	spin_unlock(&ci->i_ceph_lock);
2752
2753	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2754	     last ? " last" : "", put ? " put" : "");
2755
2756	if (last && !flushsnaps)
2757		ceph_check_caps(ci, 0, NULL);
2758	else if (flushsnaps)
2759		ceph_flush_snaps(ci, NULL);
2760	if (wake)
2761		wake_up_all(&ci->i_cap_wq);
2762	while (put-- > 0)
2763		iput(inode);
2764}
2765
2766/*
2767 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2768 * context.  Adjust per-snap dirty page accounting as appropriate.
2769 * Once all dirty data for a cap_snap is flushed, flush snapped file
2770 * metadata back to the MDS.  If we dropped the last ref, call
2771 * ceph_check_caps.
2772 */
2773void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2774				struct ceph_snap_context *snapc)
2775{
2776	struct inode *inode = &ci->vfs_inode;
2777	struct ceph_cap_snap *capsnap = NULL;
2778	int put = 0;
2779	bool last = false;
2780	bool found = false;
2781	bool flush_snaps = false;
2782	bool complete_capsnap = false;
2783
2784	spin_lock(&ci->i_ceph_lock);
2785	ci->i_wrbuffer_ref -= nr;
2786	if (ci->i_wrbuffer_ref == 0) {
2787		last = true;
2788		put++;
2789	}
2790
2791	if (ci->i_head_snapc == snapc) {
2792		ci->i_wrbuffer_ref_head -= nr;
2793		if (ci->i_wrbuffer_ref_head == 0 &&
2794		    ci->i_wr_ref == 0 &&
2795		    ci->i_dirty_caps == 0 &&
2796		    ci->i_flushing_caps == 0) {
2797			BUG_ON(!ci->i_head_snapc);
2798			ceph_put_snap_context(ci->i_head_snapc);
2799			ci->i_head_snapc = NULL;
2800		}
2801		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2802		     inode,
2803		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2804		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2805		     last ? " LAST" : "");
2806	} else {
2807		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2808			if (capsnap->context == snapc) {
2809				found = true;
2810				break;
2811			}
2812		}
2813		BUG_ON(!found);
2814		capsnap->dirty_pages -= nr;
2815		if (capsnap->dirty_pages == 0) {
2816			complete_capsnap = true;
2817			if (!capsnap->writing) {
2818				if (ceph_try_drop_cap_snap(ci, capsnap)) {
2819					put++;
2820				} else {
2821					ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
2822					flush_snaps = true;
2823				}
2824			}
2825		}
2826		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2827		     " snap %lld %d/%d -> %d/%d %s%s\n",
2828		     inode, capsnap, capsnap->context->seq,
2829		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2830		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2831		     last ? " (wrbuffer last)" : "",
2832		     complete_capsnap ? " (complete capsnap)" : "");
2833	}
2834
2835	spin_unlock(&ci->i_ceph_lock);
2836
2837	if (last) {
2838		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2839	} else if (flush_snaps) {
2840		ceph_flush_snaps(ci, NULL);
2841	}
2842	if (complete_capsnap)
2843		wake_up_all(&ci->i_cap_wq);
2844	while (put-- > 0)
2845		iput(inode);
 
 
2846}
2847
2848/*
2849 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
2850 */
2851static void invalidate_aliases(struct inode *inode)
2852{
2853	struct dentry *dn, *prev = NULL;
2854
2855	dout("invalidate_aliases inode %p\n", inode);
2856	d_prune_aliases(inode);
2857	/*
2858	 * For non-directory inode, d_find_alias() only returns
2859	 * hashed dentry. After calling d_invalidate(), the
2860	 * dentry becomes unhashed.
2861	 *
2862	 * For directory inode, d_find_alias() can return
2863	 * unhashed dentry. But directory inode should have
2864	 * one alias at most.
2865	 */
2866	while ((dn = d_find_alias(inode))) {
2867		if (dn == prev) {
2868			dput(dn);
2869			break;
2870		}
2871		d_invalidate(dn);
2872		if (prev)
2873			dput(prev);
2874		prev = dn;
2875	}
2876	if (prev)
2877		dput(prev);
2878}
2879
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2880/*
2881 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
2882 * actually be a revocation if it specifies a smaller cap set.)
2883 *
2884 * caller holds s_mutex and i_ceph_lock, we drop both.
2885 */
2886static void handle_cap_grant(struct ceph_mds_client *mdsc,
2887			     struct inode *inode, struct ceph_mds_caps *grant,
2888			     struct ceph_string **pns, u64 inline_version,
2889			     void *inline_data, u32 inline_len,
2890			     struct ceph_buffer *xattr_buf,
2891			     struct ceph_mds_session *session,
2892			     struct ceph_cap *cap, int issued)
 
 
 
2893	__releases(ci->i_ceph_lock)
2894	__releases(mdsc->snap_rwsem)
2895{
2896	struct ceph_inode_info *ci = ceph_inode(inode);
2897	int mds = session->s_mds;
2898	int seq = le32_to_cpu(grant->seq);
2899	int newcaps = le32_to_cpu(grant->caps);
2900	int used, wanted, dirty;
2901	u64 size = le64_to_cpu(grant->size);
2902	u64 max_size = le64_to_cpu(grant->max_size);
2903	struct timespec mtime, atime, ctime;
2904	int check_caps = 0;
2905	bool wake = false;
2906	bool writeback = false;
2907	bool queue_trunc = false;
2908	bool queue_invalidate = false;
2909	bool deleted_inode = false;
2910	bool fill_inline = false;
2911
2912	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
2913	     inode, cap, mds, seq, ceph_cap_string(newcaps));
2914	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2915		inode->i_size);
2916
2917
2918	/*
2919	 * auth mds of the inode changed. we received the cap export message,
2920	 * but still haven't received the cap import message. handle_cap_export
2921	 * updated the new auth MDS' cap.
2922	 *
2923	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
2924	 * that was sent before the cap import message. So don't remove caps.
2925	 */
2926	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
2927		WARN_ON(cap != ci->i_auth_cap);
2928		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
2929		seq = cap->seq;
2930		newcaps |= cap->issued;
2931	}
2932
2933	/*
2934	 * If CACHE is being revoked, and we have no dirty buffers,
2935	 * try to invalidate (once).  (If there are dirty buffers, we
2936	 * will invalidate _after_ writeback.)
2937	 */
2938	if (!S_ISDIR(inode->i_mode) && /* don't invalidate readdir cache */
2939	    ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
2940	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2941	    !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
2942		if (try_nonblocking_invalidate(inode)) {
2943			/* there were locked pages.. invalidate later
2944			   in a separate thread. */
2945			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2946				queue_invalidate = true;
2947				ci->i_rdcache_revoking = ci->i_rdcache_gen;
2948			}
2949		}
2950	}
2951
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2952	/* side effects now are allowed */
2953	cap->cap_gen = session->s_cap_gen;
2954	cap->seq = seq;
2955
2956	__check_cap_issue(ci, cap, newcaps);
2957
 
 
2958	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
2959	    (issued & CEPH_CAP_AUTH_EXCL) == 0) {
2960		inode->i_mode = le32_to_cpu(grant->mode);
2961		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
2962		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
 
2963		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2964		     from_kuid(&init_user_ns, inode->i_uid),
2965		     from_kgid(&init_user_ns, inode->i_gid));
2966	}
2967
2968	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
2969	    (issued & CEPH_CAP_LINK_EXCL) == 0) {
2970		set_nlink(inode, le32_to_cpu(grant->nlink));
2971		if (inode->i_nlink == 0 &&
2972		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
2973			deleted_inode = true;
2974	}
2975
2976	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
 
2977		int len = le32_to_cpu(grant->xattr_len);
2978		u64 version = le64_to_cpu(grant->xattr_version);
2979
2980		if (version > ci->i_xattrs.version) {
2981			dout(" got new xattrs v%llu on %p len %d\n",
2982			     version, inode, len);
2983			if (ci->i_xattrs.blob)
2984				ceph_buffer_put(ci->i_xattrs.blob);
2985			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2986			ci->i_xattrs.version = version;
2987			ceph_forget_all_cached_acls(inode);
 
2988		}
2989	}
2990
2991	if (newcaps & CEPH_CAP_ANY_RD) {
 
2992		/* ctime/mtime/atime? */
2993		ceph_decode_timespec(&mtime, &grant->mtime);
2994		ceph_decode_timespec(&atime, &grant->atime);
2995		ceph_decode_timespec(&ctime, &grant->ctime);
2996		ceph_fill_file_time(inode, issued,
2997				    le32_to_cpu(grant->time_warp_seq),
2998				    &ctime, &mtime, &atime);
2999	}
3000
 
 
 
 
 
3001	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
3002		/* file layout may have changed */
3003		s64 old_pool = ci->i_layout.pool_id;
3004		struct ceph_string *old_ns;
3005
3006		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
3007		old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
3008					lockdep_is_held(&ci->i_ceph_lock));
3009		rcu_assign_pointer(ci->i_layout.pool_ns, *pns);
3010
3011		if (ci->i_layout.pool_id != old_pool || *pns != old_ns)
 
3012			ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
3013
3014		*pns = old_ns;
3015
3016		/* size/truncate_seq? */
3017		queue_trunc = ceph_fill_file_size(inode, issued,
3018					le32_to_cpu(grant->truncate_seq),
3019					le64_to_cpu(grant->truncate_size),
3020					size);
3021		/* max size increase? */
3022		if (ci->i_auth_cap == cap && max_size != ci->i_max_size) {
 
 
3023			dout("max_size %lld -> %llu\n",
3024			     ci->i_max_size, max_size);
3025			ci->i_max_size = max_size;
3026			if (max_size >= ci->i_wanted_max_size) {
3027				ci->i_wanted_max_size = 0;  /* reset */
3028				ci->i_requested_max_size = 0;
3029			}
3030			wake = true;
 
 
 
 
3031		}
3032	}
3033
3034	/* check cap bits */
3035	wanted = __ceph_caps_wanted(ci);
3036	used = __ceph_caps_used(ci);
3037	dirty = __ceph_caps_dirty(ci);
3038	dout(" my wanted = %s, used = %s, dirty %s\n",
3039	     ceph_cap_string(wanted),
3040	     ceph_cap_string(used),
3041	     ceph_cap_string(dirty));
3042	if (wanted != le32_to_cpu(grant->wanted)) {
3043		dout("mds wanted %s -> %s\n",
3044		     ceph_cap_string(le32_to_cpu(grant->wanted)),
3045		     ceph_cap_string(wanted));
3046		/* imported cap may not have correct mds_wanted */
3047		if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT)
3048			check_caps = 1;
 
 
 
 
 
 
 
3049	}
3050
3051	/* revocation, grant, or no-op? */
3052	if (cap->issued & ~newcaps) {
3053		int revoking = cap->issued & ~newcaps;
3054
3055		dout("revocation: %s -> %s (revoking %s)\n",
3056		     ceph_cap_string(cap->issued),
3057		     ceph_cap_string(newcaps),
3058		     ceph_cap_string(revoking));
3059		if (revoking & used & CEPH_CAP_FILE_BUFFER)
3060			writeback = true;  /* initiate writeback; will delay ack */
3061		else if (revoking == CEPH_CAP_FILE_CACHE &&
3062			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3063			 queue_invalidate)
3064			; /* do nothing yet, invalidation will be queued */
3065		else if (cap == ci->i_auth_cap)
3066			check_caps = 1; /* check auth cap only */
3067		else
3068			check_caps = 2; /* check all caps */
3069		cap->issued = newcaps;
3070		cap->implemented |= newcaps;
3071	} else if (cap->issued == newcaps) {
3072		dout("caps unchanged: %s -> %s\n",
3073		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
3074	} else {
3075		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
3076		     ceph_cap_string(newcaps));
3077		/* non-auth MDS is revoking the newly grant caps ? */
3078		if (cap == ci->i_auth_cap &&
3079		    __ceph_caps_revoking_other(ci, cap, newcaps))
3080		    check_caps = 2;
3081
3082		cap->issued = newcaps;
3083		cap->implemented |= newcaps; /* add bits only, to
3084					      * avoid stepping on a
3085					      * pending revocation */
3086		wake = true;
3087	}
3088	BUG_ON(cap->issued & ~cap->implemented);
3089
3090	if (inline_version > 0 && inline_version >= ci->i_inline_version) {
3091		ci->i_inline_version = inline_version;
 
3092		if (ci->i_inline_version != CEPH_INLINE_NONE &&
3093		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
3094			fill_inline = true;
3095	}
3096
3097	if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
3098		if (newcaps & ~issued)
3099			wake = true;
3100		kick_flushing_inode_caps(mdsc, session, inode);
3101		up_read(&mdsc->snap_rwsem);
3102	} else {
3103		spin_unlock(&ci->i_ceph_lock);
3104	}
3105
3106	if (fill_inline)
3107		ceph_fill_inline_data(inode, NULL, inline_data, inline_len);
 
3108
3109	if (queue_trunc)
3110		ceph_queue_vmtruncate(inode);
3111
3112	if (writeback)
3113		/*
3114		 * queue inode for writeback: we can't actually call
3115		 * filemap_write_and_wait, etc. from message handler
3116		 * context.
3117		 */
3118		ceph_queue_writeback(inode);
3119	if (queue_invalidate)
3120		ceph_queue_invalidate(inode);
3121	if (deleted_inode)
3122		invalidate_aliases(inode);
3123	if (wake)
3124		wake_up_all(&ci->i_cap_wq);
3125
3126	if (check_caps == 1)
3127		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
3128				session);
3129	else if (check_caps == 2)
3130		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
3131	else
3132		mutex_unlock(&session->s_mutex);
3133}
3134
3135/*
3136 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
3137 * MDS has been safely committed.
3138 */
3139static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
3140				 struct ceph_mds_caps *m,
3141				 struct ceph_mds_session *session,
3142				 struct ceph_cap *cap)
3143	__releases(ci->i_ceph_lock)
3144{
3145	struct ceph_inode_info *ci = ceph_inode(inode);
3146	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3147	struct ceph_cap_flush *cf, *tmp_cf;
3148	LIST_HEAD(to_remove);
3149	unsigned seq = le32_to_cpu(m->seq);
3150	int dirty = le32_to_cpu(m->dirty);
3151	int cleaned = 0;
3152	bool drop = false;
3153	bool wake_ci = 0;
3154	bool wake_mdsc = 0;
3155
3156	list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) {
3157		if (cf->tid == flush_tid)
3158			cleaned = cf->caps;
3159		if (cf->caps == 0) /* capsnap */
3160			continue;
3161		if (cf->tid <= flush_tid) {
3162			if (__finish_cap_flush(NULL, ci, cf))
3163				wake_ci = true;
3164			list_add_tail(&cf->i_list, &to_remove);
3165		} else {
3166			cleaned &= ~cf->caps;
3167			if (!cleaned)
3168				break;
3169		}
3170	}
3171
3172	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
3173	     " flushing %s -> %s\n",
3174	     inode, session->s_mds, seq, ceph_cap_string(dirty),
3175	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
3176	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
3177
3178	if (list_empty(&to_remove) && !cleaned)
3179		goto out;
3180
3181	ci->i_flushing_caps &= ~cleaned;
3182
3183	spin_lock(&mdsc->cap_dirty_lock);
3184
3185	list_for_each_entry(cf, &to_remove, i_list) {
3186		if (__finish_cap_flush(mdsc, NULL, cf))
3187			wake_mdsc = true;
3188	}
3189
3190	if (ci->i_flushing_caps == 0) {
3191		if (list_empty(&ci->i_cap_flush_list)) {
3192			list_del_init(&ci->i_flushing_item);
3193			if (!list_empty(&session->s_cap_flushing)) {
3194				dout(" mds%d still flushing cap on %p\n",
3195				     session->s_mds,
3196				     &list_first_entry(&session->s_cap_flushing,
3197						struct ceph_inode_info,
3198						i_flushing_item)->vfs_inode);
3199			}
3200		}
3201		mdsc->num_cap_flushing--;
3202		dout(" inode %p now !flushing\n", inode);
3203
3204		if (ci->i_dirty_caps == 0) {
3205			dout(" inode %p now clean\n", inode);
3206			BUG_ON(!list_empty(&ci->i_dirty_item));
3207			drop = true;
3208			if (ci->i_wr_ref == 0 &&
3209			    ci->i_wrbuffer_ref_head == 0) {
3210				BUG_ON(!ci->i_head_snapc);
3211				ceph_put_snap_context(ci->i_head_snapc);
3212				ci->i_head_snapc = NULL;
3213			}
3214		} else {
3215			BUG_ON(list_empty(&ci->i_dirty_item));
3216		}
3217	}
3218	spin_unlock(&mdsc->cap_dirty_lock);
3219
3220out:
3221	spin_unlock(&ci->i_ceph_lock);
3222
3223	while (!list_empty(&to_remove)) {
3224		cf = list_first_entry(&to_remove,
3225				      struct ceph_cap_flush, i_list);
3226		list_del(&cf->i_list);
3227		ceph_free_cap_flush(cf);
3228	}
3229
3230	if (wake_ci)
3231		wake_up_all(&ci->i_cap_wq);
3232	if (wake_mdsc)
3233		wake_up_all(&mdsc->cap_flushing_wq);
3234	if (drop)
3235		iput(inode);
3236}
3237
3238/*
3239 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
3240 * throw away our cap_snap.
3241 *
3242 * Caller hold s_mutex.
3243 */
3244static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
3245				     struct ceph_mds_caps *m,
3246				     struct ceph_mds_session *session)
3247{
3248	struct ceph_inode_info *ci = ceph_inode(inode);
3249	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3250	u64 follows = le64_to_cpu(m->snap_follows);
3251	struct ceph_cap_snap *capsnap;
3252	bool flushed = false;
3253	bool wake_ci = false;
3254	bool wake_mdsc = false;
3255
3256	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
3257	     inode, ci, session->s_mds, follows);
3258
3259	spin_lock(&ci->i_ceph_lock);
3260	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
3261		if (capsnap->follows == follows) {
3262			if (capsnap->cap_flush.tid != flush_tid) {
3263				dout(" cap_snap %p follows %lld tid %lld !="
3264				     " %lld\n", capsnap, follows,
3265				     flush_tid, capsnap->cap_flush.tid);
3266				break;
3267			}
3268			flushed = true;
3269			break;
3270		} else {
3271			dout(" skipping cap_snap %p follows %lld\n",
3272			     capsnap, capsnap->follows);
3273		}
3274	}
3275	if (flushed) {
3276		WARN_ON(capsnap->dirty_pages || capsnap->writing);
3277		dout(" removing %p cap_snap %p follows %lld\n",
3278		     inode, capsnap, follows);
3279		list_del(&capsnap->ci_item);
3280		if (__finish_cap_flush(NULL, ci, &capsnap->cap_flush))
3281			wake_ci = true;
3282
3283		spin_lock(&mdsc->cap_dirty_lock);
3284
3285		if (list_empty(&ci->i_cap_flush_list))
3286			list_del_init(&ci->i_flushing_item);
3287
3288		if (__finish_cap_flush(mdsc, NULL, &capsnap->cap_flush))
3289			wake_mdsc = true;
3290
3291		spin_unlock(&mdsc->cap_dirty_lock);
3292	}
3293	spin_unlock(&ci->i_ceph_lock);
3294	if (flushed) {
3295		ceph_put_snap_context(capsnap->context);
3296		ceph_put_cap_snap(capsnap);
3297		if (wake_ci)
3298			wake_up_all(&ci->i_cap_wq);
3299		if (wake_mdsc)
3300			wake_up_all(&mdsc->cap_flushing_wq);
3301		iput(inode);
3302	}
3303}
3304
3305/*
3306 * Handle TRUNC from MDS, indicating file truncation.
3307 *
3308 * caller hold s_mutex.
3309 */
3310static void handle_cap_trunc(struct inode *inode,
3311			     struct ceph_mds_caps *trunc,
3312			     struct ceph_mds_session *session)
3313	__releases(ci->i_ceph_lock)
3314{
3315	struct ceph_inode_info *ci = ceph_inode(inode);
3316	int mds = session->s_mds;
3317	int seq = le32_to_cpu(trunc->seq);
3318	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
3319	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
3320	u64 size = le64_to_cpu(trunc->size);
3321	int implemented = 0;
3322	int dirty = __ceph_caps_dirty(ci);
3323	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
3324	int queue_trunc = 0;
3325
3326	issued |= implemented | dirty;
3327
3328	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
3329	     inode, mds, seq, truncate_size, truncate_seq);
3330	queue_trunc = ceph_fill_file_size(inode, issued,
3331					  truncate_seq, truncate_size, size);
3332	spin_unlock(&ci->i_ceph_lock);
3333
3334	if (queue_trunc)
3335		ceph_queue_vmtruncate(inode);
3336}
3337
3338/*
3339 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
3340 * different one.  If we are the most recent migration we've seen (as
3341 * indicated by mseq), make note of the migrating cap bits for the
3342 * duration (until we see the corresponding IMPORT).
3343 *
3344 * caller holds s_mutex
3345 */
3346static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
3347			      struct ceph_mds_cap_peer *ph,
3348			      struct ceph_mds_session *session)
3349{
3350	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
3351	struct ceph_mds_session *tsession = NULL;
3352	struct ceph_cap *cap, *tcap, *new_cap = NULL;
3353	struct ceph_inode_info *ci = ceph_inode(inode);
3354	u64 t_cap_id;
3355	unsigned mseq = le32_to_cpu(ex->migrate_seq);
3356	unsigned t_seq, t_mseq;
3357	int target, issued;
3358	int mds = session->s_mds;
3359
3360	if (ph) {
3361		t_cap_id = le64_to_cpu(ph->cap_id);
3362		t_seq = le32_to_cpu(ph->seq);
3363		t_mseq = le32_to_cpu(ph->mseq);
3364		target = le32_to_cpu(ph->mds);
3365	} else {
3366		t_cap_id = t_seq = t_mseq = 0;
3367		target = -1;
3368	}
3369
3370	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
3371	     inode, ci, mds, mseq, target);
3372retry:
3373	spin_lock(&ci->i_ceph_lock);
3374	cap = __get_cap_for_mds(ci, mds);
3375	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
3376		goto out_unlock;
3377
3378	if (target < 0) {
3379		__ceph_remove_cap(cap, false);
3380		if (!ci->i_auth_cap)
3381			ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
 
3382		goto out_unlock;
3383	}
3384
3385	/*
3386	 * now we know we haven't received the cap import message yet
3387	 * because the exported cap still exist.
3388	 */
3389
3390	issued = cap->issued;
3391	WARN_ON(issued != cap->implemented);
 
 
 
 
 
 
 
3392
3393	tcap = __get_cap_for_mds(ci, target);
3394	if (tcap) {
3395		/* already have caps from the target */
3396		if (tcap->cap_id != t_cap_id ||
3397		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
3398			dout(" updating import cap %p mds%d\n", tcap, target);
3399			tcap->cap_id = t_cap_id;
3400			tcap->seq = t_seq - 1;
3401			tcap->issue_seq = t_seq - 1;
3402			tcap->mseq = t_mseq;
3403			tcap->issued |= issued;
3404			tcap->implemented |= issued;
3405			if (cap == ci->i_auth_cap)
3406				ci->i_auth_cap = tcap;
 
3407			if (!list_empty(&ci->i_cap_flush_list) &&
3408			    ci->i_auth_cap == tcap) {
3409				spin_lock(&mdsc->cap_dirty_lock);
3410				list_move_tail(&ci->i_flushing_item,
3411					       &tcap->session->s_cap_flushing);
3412				spin_unlock(&mdsc->cap_dirty_lock);
3413			}
3414		}
3415		__ceph_remove_cap(cap, false);
3416		goto out_unlock;
3417	} else if (tsession) {
3418		/* add placeholder for the export tagert */
3419		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
 
3420		ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
3421			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
3422
 
 
 
 
 
 
 
 
3423		__ceph_remove_cap(cap, false);
3424		goto out_unlock;
3425	}
3426
3427	spin_unlock(&ci->i_ceph_lock);
3428	mutex_unlock(&session->s_mutex);
3429
3430	/* open target session */
3431	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
3432	if (!IS_ERR(tsession)) {
3433		if (mds > target) {
3434			mutex_lock(&session->s_mutex);
3435			mutex_lock_nested(&tsession->s_mutex,
3436					  SINGLE_DEPTH_NESTING);
3437		} else {
3438			mutex_lock(&tsession->s_mutex);
3439			mutex_lock_nested(&session->s_mutex,
3440					  SINGLE_DEPTH_NESTING);
3441		}
3442		new_cap = ceph_get_cap(mdsc, NULL);
3443	} else {
3444		WARN_ON(1);
3445		tsession = NULL;
3446		target = -1;
3447	}
3448	goto retry;
3449
3450out_unlock:
3451	spin_unlock(&ci->i_ceph_lock);
3452	mutex_unlock(&session->s_mutex);
3453	if (tsession) {
3454		mutex_unlock(&tsession->s_mutex);
3455		ceph_put_mds_session(tsession);
3456	}
3457	if (new_cap)
3458		ceph_put_cap(mdsc, new_cap);
3459}
3460
3461/*
3462 * Handle cap IMPORT.
3463 *
3464 * caller holds s_mutex. acquires i_ceph_lock
3465 */
3466static void handle_cap_import(struct ceph_mds_client *mdsc,
3467			      struct inode *inode, struct ceph_mds_caps *im,
3468			      struct ceph_mds_cap_peer *ph,
3469			      struct ceph_mds_session *session,
3470			      struct ceph_cap **target_cap, int *old_issued)
3471	__acquires(ci->i_ceph_lock)
3472{
3473	struct ceph_inode_info *ci = ceph_inode(inode);
3474	struct ceph_cap *cap, *ocap, *new_cap = NULL;
3475	int mds = session->s_mds;
3476	int issued;
3477	unsigned caps = le32_to_cpu(im->caps);
3478	unsigned wanted = le32_to_cpu(im->wanted);
3479	unsigned seq = le32_to_cpu(im->seq);
3480	unsigned mseq = le32_to_cpu(im->migrate_seq);
3481	u64 realmino = le64_to_cpu(im->realm);
3482	u64 cap_id = le64_to_cpu(im->cap_id);
3483	u64 p_cap_id;
3484	int peer;
3485
3486	if (ph) {
3487		p_cap_id = le64_to_cpu(ph->cap_id);
3488		peer = le32_to_cpu(ph->mds);
3489	} else {
3490		p_cap_id = 0;
3491		peer = -1;
3492	}
3493
3494	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
3495	     inode, ci, mds, mseq, peer);
3496
3497retry:
3498	spin_lock(&ci->i_ceph_lock);
3499	cap = __get_cap_for_mds(ci, mds);
3500	if (!cap) {
3501		if (!new_cap) {
3502			spin_unlock(&ci->i_ceph_lock);
3503			new_cap = ceph_get_cap(mdsc, NULL);
3504			goto retry;
3505		}
3506		cap = new_cap;
3507	} else {
3508		if (new_cap) {
3509			ceph_put_cap(mdsc, new_cap);
3510			new_cap = NULL;
3511		}
3512	}
3513
3514	__ceph_caps_issued(ci, &issued);
3515	issued |= __ceph_caps_dirty(ci);
3516
3517	ceph_add_cap(inode, session, cap_id, -1, caps, wanted, seq, mseq,
3518		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
3519
3520	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
3521	if (ocap && ocap->cap_id == p_cap_id) {
3522		dout(" remove export cap %p mds%d flags %d\n",
3523		     ocap, peer, ph->flags);
3524		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
3525		    (ocap->seq != le32_to_cpu(ph->seq) ||
3526		     ocap->mseq != le32_to_cpu(ph->mseq))) {
3527			pr_err("handle_cap_import: mismatched seq/mseq: "
3528			       "ino (%llx.%llx) mds%d seq %d mseq %d "
3529			       "importer mds%d has peer seq %d mseq %d\n",
3530			       ceph_vinop(inode), peer, ocap->seq,
3531			       ocap->mseq, mds, le32_to_cpu(ph->seq),
3532			       le32_to_cpu(ph->mseq));
 
3533		}
3534		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
3535	}
3536
3537	/* make sure we re-request max_size, if necessary */
3538	ci->i_wanted_max_size = 0;
3539	ci->i_requested_max_size = 0;
3540
3541	*old_issued = issued;
3542	*target_cap = cap;
3543}
3544
3545/*
3546 * Handle a caps message from the MDS.
3547 *
3548 * Identify the appropriate session, inode, and call the right handler
3549 * based on the cap op.
3550 */
3551void ceph_handle_caps(struct ceph_mds_session *session,
3552		      struct ceph_msg *msg)
3553{
3554	struct ceph_mds_client *mdsc = session->s_mdsc;
3555	struct super_block *sb = mdsc->fsc->sb;
3556	struct inode *inode;
3557	struct ceph_inode_info *ci;
3558	struct ceph_cap *cap;
3559	struct ceph_mds_caps *h;
3560	struct ceph_mds_cap_peer *peer = NULL;
3561	struct ceph_snap_realm *realm = NULL;
3562	struct ceph_string *pool_ns = NULL;
3563	int mds = session->s_mds;
3564	int op, issued;
3565	u32 seq, mseq;
3566	struct ceph_vino vino;
3567	u64 tid;
3568	u64 inline_version = 0;
3569	void *inline_data = NULL;
3570	u32  inline_len = 0;
3571	void *snaptrace;
3572	size_t snaptrace_len;
3573	void *p, *end;
 
3574
3575	dout("handle_caps from mds%d\n", mds);
3576
3577	/* decode */
3578	end = msg->front.iov_base + msg->front.iov_len;
3579	tid = le64_to_cpu(msg->hdr.tid);
3580	if (msg->front.iov_len < sizeof(*h))
3581		goto bad;
3582	h = msg->front.iov_base;
3583	op = le32_to_cpu(h->op);
3584	vino.ino = le64_to_cpu(h->ino);
3585	vino.snap = CEPH_NOSNAP;
3586	seq = le32_to_cpu(h->seq);
3587	mseq = le32_to_cpu(h->migrate_seq);
3588
3589	snaptrace = h + 1;
3590	snaptrace_len = le32_to_cpu(h->snap_trace_len);
3591	p = snaptrace + snaptrace_len;
3592
3593	if (le16_to_cpu(msg->hdr.version) >= 2) {
3594		u32 flock_len;
3595		ceph_decode_32_safe(&p, end, flock_len, bad);
3596		if (p + flock_len > end)
3597			goto bad;
3598		p += flock_len;
3599	}
3600
3601	if (le16_to_cpu(msg->hdr.version) >= 3) {
3602		if (op == CEPH_CAP_OP_IMPORT) {
3603			if (p + sizeof(*peer) > end)
3604				goto bad;
3605			peer = p;
3606			p += sizeof(*peer);
3607		} else if (op == CEPH_CAP_OP_EXPORT) {
3608			/* recorded in unused fields */
3609			peer = (void *)&h->size;
3610		}
3611	}
3612
3613	if (le16_to_cpu(msg->hdr.version) >= 4) {
3614		ceph_decode_64_safe(&p, end, inline_version, bad);
3615		ceph_decode_32_safe(&p, end, inline_len, bad);
3616		if (p + inline_len > end)
3617			goto bad;
3618		inline_data = p;
3619		p += inline_len;
3620	}
3621
3622	if (le16_to_cpu(msg->hdr.version) >= 8) {
 
 
 
 
 
 
 
 
3623		u64 flush_tid;
3624		u32 caller_uid, caller_gid;
3625		u32 osd_epoch_barrier;
3626		u32 pool_ns_len;
3627		/* version >= 5 */
3628		ceph_decode_32_safe(&p, end, osd_epoch_barrier, bad);
3629		/* version >= 6 */
3630		ceph_decode_64_safe(&p, end, flush_tid, bad);
3631		/* version >= 7 */
3632		ceph_decode_32_safe(&p, end, caller_uid, bad);
3633		ceph_decode_32_safe(&p, end, caller_gid, bad);
3634		/* version >= 8 */
3635		ceph_decode_32_safe(&p, end, pool_ns_len, bad);
3636		if (pool_ns_len > 0) {
3637			ceph_decode_need(&p, end, pool_ns_len, bad);
3638			pool_ns = ceph_find_or_create_string(p, pool_ns_len);
 
3639			p += pool_ns_len;
3640		}
3641	}
3642
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3643	/* lookup ino */
3644	inode = ceph_find_inode(sb, vino);
3645	ci = ceph_inode(inode);
3646	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
3647	     vino.snap, inode);
3648
3649	mutex_lock(&session->s_mutex);
3650	session->s_seq++;
3651	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
3652	     (unsigned)seq);
3653
3654	if (!inode) {
3655		dout(" i don't have ino %llx\n", vino.ino);
3656
3657		if (op == CEPH_CAP_OP_IMPORT) {
3658			cap = ceph_get_cap(mdsc, NULL);
3659			cap->cap_ino = vino.ino;
3660			cap->queue_release = 1;
3661			cap->cap_id = le64_to_cpu(h->cap_id);
3662			cap->mseq = mseq;
3663			cap->seq = seq;
3664			cap->issue_seq = seq;
3665			spin_lock(&session->s_cap_lock);
3666			list_add_tail(&cap->session_caps,
3667					&session->s_cap_releases);
3668			session->s_num_cap_releases++;
3669			spin_unlock(&session->s_cap_lock);
3670		}
3671		goto flush_cap_releases;
3672	}
3673
3674	/* these will work even if we don't have a cap yet */
3675	switch (op) {
3676	case CEPH_CAP_OP_FLUSHSNAP_ACK:
3677		handle_cap_flushsnap_ack(inode, tid, h, session);
 
3678		goto done;
3679
3680	case CEPH_CAP_OP_EXPORT:
3681		handle_cap_export(inode, h, peer, session);
3682		goto done_unlocked;
3683
3684	case CEPH_CAP_OP_IMPORT:
3685		realm = NULL;
3686		if (snaptrace_len) {
3687			down_write(&mdsc->snap_rwsem);
3688			ceph_update_snap_trace(mdsc, snaptrace,
3689					       snaptrace + snaptrace_len,
3690					       false, &realm);
3691			downgrade_write(&mdsc->snap_rwsem);
3692		} else {
3693			down_read(&mdsc->snap_rwsem);
3694		}
3695		handle_cap_import(mdsc, inode, h, peer, session,
3696				  &cap, &issued);
3697		handle_cap_grant(mdsc, inode, h, &pool_ns,
3698				 inline_version, inline_data, inline_len,
3699				 msg->middle, session, cap, issued);
3700		if (realm)
3701			ceph_put_snap_realm(mdsc, realm);
3702		goto done_unlocked;
3703	}
3704
3705	/* the rest require a cap */
3706	spin_lock(&ci->i_ceph_lock);
3707	cap = __get_cap_for_mds(ceph_inode(inode), mds);
3708	if (!cap) {
3709		dout(" no cap on %p ino %llx.%llx from mds%d\n",
3710		     inode, ceph_ino(inode), ceph_snap(inode), mds);
 
3711		spin_unlock(&ci->i_ceph_lock);
3712		goto flush_cap_releases;
3713	}
3714
3715	/* note that each of these drops i_ceph_lock for us */
3716	switch (op) {
3717	case CEPH_CAP_OP_REVOKE:
3718	case CEPH_CAP_OP_GRANT:
3719		__ceph_caps_issued(ci, &issued);
3720		issued |= __ceph_caps_dirty(ci);
3721		handle_cap_grant(mdsc, inode, h, &pool_ns,
3722				 inline_version, inline_data, inline_len,
3723				 msg->middle, session, cap, issued);
3724		goto done_unlocked;
3725
3726	case CEPH_CAP_OP_FLUSH_ACK:
3727		handle_cap_flush_ack(inode, tid, h, session, cap);
 
3728		break;
3729
3730	case CEPH_CAP_OP_TRUNC:
3731		handle_cap_trunc(inode, h, session);
3732		break;
3733
3734	default:
3735		spin_unlock(&ci->i_ceph_lock);
3736		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
3737		       ceph_cap_op_name(op));
3738	}
3739
3740	goto done;
 
 
 
 
 
 
3741
3742flush_cap_releases:
3743	/*
3744	 * send any cap release message to try to move things
3745	 * along for the mds (who clearly thinks we still have this
3746	 * cap).
3747	 */
3748	ceph_send_cap_releases(mdsc, session);
3749
3750done:
3751	mutex_unlock(&session->s_mutex);
3752done_unlocked:
3753	iput(inode);
3754	ceph_put_string(pool_ns);
3755	return;
3756
3757bad:
3758	pr_err("ceph_handle_caps: corrupt message\n");
3759	ceph_msg_dump(msg);
3760	return;
3761}
3762
3763/*
3764 * Delayed work handler to process end of delayed cap release LRU list.
3765 */
3766void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
3767{
 
3768	struct ceph_inode_info *ci;
3769	int flags = CHECK_CAPS_NODELAY;
3770
3771	dout("check_delayed_caps\n");
3772	while (1) {
3773		spin_lock(&mdsc->cap_delay_lock);
3774		if (list_empty(&mdsc->cap_delay_list))
3775			break;
3776		ci = list_first_entry(&mdsc->cap_delay_list,
3777				      struct ceph_inode_info,
3778				      i_cap_delay_list);
3779		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
3780		    time_before(jiffies, ci->i_hold_caps_max))
3781			break;
3782		list_del_init(&ci->i_cap_delay_list);
 
 
3783		spin_unlock(&mdsc->cap_delay_lock);
3784		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
3785		ceph_check_caps(ci, flags, NULL);
 
 
 
 
 
3786	}
3787	spin_unlock(&mdsc->cap_delay_lock);
3788}
3789
3790/*
3791 * Flush all dirty caps to the mds
3792 */
3793void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
3794{
3795	struct ceph_inode_info *ci;
3796	struct inode *inode;
3797
3798	dout("flush_dirty_caps\n");
3799	spin_lock(&mdsc->cap_dirty_lock);
3800	while (!list_empty(&mdsc->cap_dirty)) {
3801		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
3802				      i_dirty_item);
3803		inode = &ci->vfs_inode;
3804		ihold(inode);
3805		dout("flush_dirty_caps %p\n", inode);
3806		spin_unlock(&mdsc->cap_dirty_lock);
3807		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
3808		iput(inode);
3809		spin_lock(&mdsc->cap_dirty_lock);
3810	}
3811	spin_unlock(&mdsc->cap_dirty_lock);
3812	dout("flush_dirty_caps done\n");
3813}
3814
3815void __ceph_get_fmode(struct ceph_inode_info *ci, int fmode)
3816{
3817	int i;
3818	int bits = (fmode << 1) | 1;
3819	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
3820		if (bits & (1 << i))
3821			ci->i_nr_by_mode[i]++;
3822	}
3823}
3824
3825/*
3826 * Drop open file reference.  If we were the last open file,
3827 * we may need to release capabilities to the MDS (or schedule
3828 * their delayed release).
3829 */
3830void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
3831{
3832	int i, last = 0;
3833	int bits = (fmode << 1) | 1;
3834	spin_lock(&ci->i_ceph_lock);
3835	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
3836		if (bits & (1 << i)) {
3837			BUG_ON(ci->i_nr_by_mode[i] == 0);
3838			if (--ci->i_nr_by_mode[i] == 0)
3839				last++;
3840		}
3841	}
3842	dout("put_fmode %p fmode %d {%d,%d,%d,%d}\n",
3843	     &ci->vfs_inode, fmode,
3844	     ci->i_nr_by_mode[0], ci->i_nr_by_mode[1],
3845	     ci->i_nr_by_mode[2], ci->i_nr_by_mode[3]);
3846	spin_unlock(&ci->i_ceph_lock);
3847
3848	if (last && ci->i_vino.snap == CEPH_NOSNAP)
3849		ceph_check_caps(ci, 0, NULL);
3850}
3851
3852/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3853 * Helpers for embedding cap and dentry lease releases into mds
3854 * requests.
3855 *
3856 * @force is used by dentry_release (below) to force inclusion of a
3857 * record for the directory inode, even when there aren't any caps to
3858 * drop.
3859 */
3860int ceph_encode_inode_release(void **p, struct inode *inode,
3861			      int mds, int drop, int unless, int force)
3862{
3863	struct ceph_inode_info *ci = ceph_inode(inode);
3864	struct ceph_cap *cap;
3865	struct ceph_mds_request_release *rel = *p;
3866	int used, dirty;
3867	int ret = 0;
3868
3869	spin_lock(&ci->i_ceph_lock);
3870	used = __ceph_caps_used(ci);
3871	dirty = __ceph_caps_dirty(ci);
3872
3873	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
3874	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3875	     ceph_cap_string(unless));
3876
3877	/* only drop unused, clean caps */
3878	drop &= ~(used | dirty);
3879
3880	cap = __get_cap_for_mds(ci, mds);
3881	if (cap && __cap_is_valid(cap)) {
3882		if (force ||
3883		    ((cap->issued & drop) &&
3884		     (cap->issued & unless) == 0)) {
3885			if ((cap->issued & drop) &&
3886			    (cap->issued & unless) == 0) {
 
 
 
 
 
 
 
 
 
3887				int wanted = __ceph_caps_wanted(ci);
3888				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
3889					wanted |= cap->mds_wanted;
3890				dout("encode_inode_release %p cap %p "
3891				     "%s -> %s, wanted %s -> %s\n", inode, cap,
3892				     ceph_cap_string(cap->issued),
3893				     ceph_cap_string(cap->issued & ~drop),
3894				     ceph_cap_string(cap->mds_wanted),
3895				     ceph_cap_string(wanted));
3896
3897				cap->issued &= ~drop;
3898				cap->implemented &= ~drop;
3899				cap->mds_wanted = wanted;
3900			} else {
3901				dout("encode_inode_release %p cap %p %s"
3902				     " (force)\n", inode, cap,
3903				     ceph_cap_string(cap->issued));
3904			}
3905
3906			rel->ino = cpu_to_le64(ceph_ino(inode));
3907			rel->cap_id = cpu_to_le64(cap->cap_id);
3908			rel->seq = cpu_to_le32(cap->seq);
3909			rel->issue_seq = cpu_to_le32(cap->issue_seq);
3910			rel->mseq = cpu_to_le32(cap->mseq);
3911			rel->caps = cpu_to_le32(cap->implemented);
3912			rel->wanted = cpu_to_le32(cap->mds_wanted);
3913			rel->dname_len = 0;
3914			rel->dname_seq = 0;
3915			*p += sizeof(*rel);
3916			ret = 1;
3917		} else {
3918			dout("encode_inode_release %p cap %p %s\n",
3919			     inode, cap, ceph_cap_string(cap->issued));
3920		}
3921	}
3922	spin_unlock(&ci->i_ceph_lock);
3923	return ret;
3924}
3925
3926int ceph_encode_dentry_release(void **p, struct dentry *dentry,
 
3927			       int mds, int drop, int unless)
3928{
3929	struct inode *dir = d_inode(dentry->d_parent);
3930	struct ceph_mds_request_release *rel = *p;
3931	struct ceph_dentry_info *di = ceph_dentry(dentry);
3932	int force = 0;
3933	int ret;
3934
3935	/*
3936	 * force an record for the directory caps if we have a dentry lease.
3937	 * this is racy (can't take i_ceph_lock and d_lock together), but it
3938	 * doesn't have to be perfect; the mds will revoke anything we don't
3939	 * release.
3940	 */
3941	spin_lock(&dentry->d_lock);
3942	if (di->lease_session && di->lease_session->s_mds == mds)
3943		force = 1;
 
 
 
 
3944	spin_unlock(&dentry->d_lock);
3945
3946	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
 
3947
3948	spin_lock(&dentry->d_lock);
3949	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
3950		dout("encode_dentry_release %p mds%d seq %d\n",
3951		     dentry, mds, (int)di->lease_seq);
3952		rel->dname_len = cpu_to_le32(dentry->d_name.len);
3953		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
3954		*p += dentry->d_name.len;
3955		rel->dname_seq = cpu_to_le32(di->lease_seq);
3956		__ceph_mdsc_drop_dentry_lease(dentry);
3957	}
3958	spin_unlock(&dentry->d_lock);
3959	return ret;
3960}
v5.4
   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#include <linux/iversion.h>
  12
  13#include "super.h"
  14#include "mds_client.h"
  15#include "cache.h"
  16#include <linux/ceph/decode.h>
  17#include <linux/ceph/messenger.h>
  18
  19/*
  20 * Capability management
  21 *
  22 * The Ceph metadata servers control client access to inode metadata
  23 * and file data by issuing capabilities, granting clients permission
  24 * to read and/or write both inode field and file data to OSDs
  25 * (storage nodes).  Each capability consists of a set of bits
  26 * indicating which operations are allowed.
  27 *
  28 * If the client holds a *_SHARED cap, the client has a coherent value
  29 * that can be safely read from the cached inode.
  30 *
  31 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
  32 * client is allowed to change inode attributes (e.g., file size,
  33 * mtime), note its dirty state in the ceph_cap, and asynchronously
  34 * flush that metadata change to the MDS.
  35 *
  36 * In the event of a conflicting operation (perhaps by another
  37 * client), the MDS will revoke the conflicting client capabilities.
  38 *
  39 * In order for a client to cache an inode, it must hold a capability
  40 * with at least one MDS server.  When inodes are released, release
  41 * notifications are batched and periodically sent en masse to the MDS
  42 * cluster to release server state.
  43 */
  44
  45static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc);
  46static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
  47				 struct ceph_mds_session *session,
  48				 struct ceph_inode_info *ci,
  49				 u64 oldest_flush_tid);
  50
  51/*
  52 * Generate readable cap strings for debugging output.
  53 */
  54#define MAX_CAP_STR 20
  55static char cap_str[MAX_CAP_STR][40];
  56static DEFINE_SPINLOCK(cap_str_lock);
  57static int last_cap_str;
  58
  59static char *gcap_string(char *s, int c)
  60{
  61	if (c & CEPH_CAP_GSHARED)
  62		*s++ = 's';
  63	if (c & CEPH_CAP_GEXCL)
  64		*s++ = 'x';
  65	if (c & CEPH_CAP_GCACHE)
  66		*s++ = 'c';
  67	if (c & CEPH_CAP_GRD)
  68		*s++ = 'r';
  69	if (c & CEPH_CAP_GWR)
  70		*s++ = 'w';
  71	if (c & CEPH_CAP_GBUFFER)
  72		*s++ = 'b';
  73	if (c & CEPH_CAP_GWREXTEND)
  74		*s++ = 'a';
  75	if (c & CEPH_CAP_GLAZYIO)
  76		*s++ = 'l';
  77	return s;
  78}
  79
  80const char *ceph_cap_string(int caps)
  81{
  82	int i;
  83	char *s;
  84	int c;
  85
  86	spin_lock(&cap_str_lock);
  87	i = last_cap_str++;
  88	if (last_cap_str == MAX_CAP_STR)
  89		last_cap_str = 0;
  90	spin_unlock(&cap_str_lock);
  91
  92	s = cap_str[i];
  93
  94	if (caps & CEPH_CAP_PIN)
  95		*s++ = 'p';
  96
  97	c = (caps >> CEPH_CAP_SAUTH) & 3;
  98	if (c) {
  99		*s++ = 'A';
 100		s = gcap_string(s, c);
 101	}
 102
 103	c = (caps >> CEPH_CAP_SLINK) & 3;
 104	if (c) {
 105		*s++ = 'L';
 106		s = gcap_string(s, c);
 107	}
 108
 109	c = (caps >> CEPH_CAP_SXATTR) & 3;
 110	if (c) {
 111		*s++ = 'X';
 112		s = gcap_string(s, c);
 113	}
 114
 115	c = caps >> CEPH_CAP_SFILE;
 116	if (c) {
 117		*s++ = 'F';
 118		s = gcap_string(s, c);
 119	}
 120
 121	if (s == cap_str[i])
 122		*s++ = '-';
 123	*s = 0;
 124	return cap_str[i];
 125}
 126
 127void ceph_caps_init(struct ceph_mds_client *mdsc)
 128{
 129	INIT_LIST_HEAD(&mdsc->caps_list);
 130	spin_lock_init(&mdsc->caps_list_lock);
 131}
 132
 133void ceph_caps_finalize(struct ceph_mds_client *mdsc)
 134{
 135	struct ceph_cap *cap;
 136
 137	spin_lock(&mdsc->caps_list_lock);
 138	while (!list_empty(&mdsc->caps_list)) {
 139		cap = list_first_entry(&mdsc->caps_list,
 140				       struct ceph_cap, caps_item);
 141		list_del(&cap->caps_item);
 142		kmem_cache_free(ceph_cap_cachep, cap);
 143	}
 144	mdsc->caps_total_count = 0;
 145	mdsc->caps_avail_count = 0;
 146	mdsc->caps_use_count = 0;
 147	mdsc->caps_reserve_count = 0;
 148	mdsc->caps_min_count = 0;
 149	spin_unlock(&mdsc->caps_list_lock);
 150}
 151
 152void ceph_adjust_caps_max_min(struct ceph_mds_client *mdsc,
 153			      struct ceph_mount_options *fsopt)
 154{
 155	spin_lock(&mdsc->caps_list_lock);
 156	mdsc->caps_min_count = fsopt->max_readdir;
 157	if (mdsc->caps_min_count < 1024)
 158		mdsc->caps_min_count = 1024;
 159	mdsc->caps_use_max = fsopt->caps_max;
 160	if (mdsc->caps_use_max > 0 &&
 161	    mdsc->caps_use_max < mdsc->caps_min_count)
 162		mdsc->caps_use_max = mdsc->caps_min_count;
 163	spin_unlock(&mdsc->caps_list_lock);
 164}
 165
 166static void __ceph_unreserve_caps(struct ceph_mds_client *mdsc, int nr_caps)
 
 167{
 168	struct ceph_cap *cap;
 169	int i;
 170
 171	if (nr_caps) {
 172		BUG_ON(mdsc->caps_reserve_count < nr_caps);
 173		mdsc->caps_reserve_count -= nr_caps;
 174		if (mdsc->caps_avail_count >=
 175		    mdsc->caps_reserve_count + mdsc->caps_min_count) {
 176			mdsc->caps_total_count -= nr_caps;
 177			for (i = 0; i < nr_caps; i++) {
 178				cap = list_first_entry(&mdsc->caps_list,
 179					struct ceph_cap, caps_item);
 180				list_del(&cap->caps_item);
 181				kmem_cache_free(ceph_cap_cachep, cap);
 182			}
 183		} else {
 184			mdsc->caps_avail_count += nr_caps;
 185		}
 186
 187		dout("%s: caps %d = %d used + %d resv + %d avail\n",
 188		     __func__,
 189		     mdsc->caps_total_count, mdsc->caps_use_count,
 190		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 191		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 192						 mdsc->caps_reserve_count +
 193						 mdsc->caps_avail_count);
 194	}
 195}
 196
 197/*
 198 * Called under mdsc->mutex.
 199 */
 200int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 201		      struct ceph_cap_reservation *ctx, int need)
 202{
 203	int i, j;
 204	struct ceph_cap *cap;
 205	int have;
 206	int alloc = 0;
 207	int max_caps;
 208	int err = 0;
 209	bool trimmed = false;
 210	struct ceph_mds_session *s;
 211	LIST_HEAD(newcaps);
 212
 213	dout("reserve caps ctx=%p need=%d\n", ctx, need);
 214
 215	/* first reserve any caps that are already allocated */
 216	spin_lock(&mdsc->caps_list_lock);
 217	if (mdsc->caps_avail_count >= need)
 218		have = need;
 219	else
 220		have = mdsc->caps_avail_count;
 221	mdsc->caps_avail_count -= have;
 222	mdsc->caps_reserve_count += have;
 223	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 224					 mdsc->caps_reserve_count +
 225					 mdsc->caps_avail_count);
 226	spin_unlock(&mdsc->caps_list_lock);
 227
 228	for (i = have; i < need; ) {
 229		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 230		if (cap) {
 231			list_add(&cap->caps_item, &newcaps);
 232			alloc++;
 233			i++;
 234			continue;
 235		}
 236
 237		if (!trimmed) {
 238			for (j = 0; j < mdsc->max_sessions; j++) {
 239				s = __ceph_lookup_mds_session(mdsc, j);
 240				if (!s)
 241					continue;
 242				mutex_unlock(&mdsc->mutex);
 243
 244				mutex_lock(&s->s_mutex);
 245				max_caps = s->s_nr_caps - (need - i);
 246				ceph_trim_caps(mdsc, s, max_caps);
 247				mutex_unlock(&s->s_mutex);
 248
 249				ceph_put_mds_session(s);
 250				mutex_lock(&mdsc->mutex);
 251			}
 252			trimmed = true;
 253
 254			spin_lock(&mdsc->caps_list_lock);
 255			if (mdsc->caps_avail_count) {
 256				int more_have;
 257				if (mdsc->caps_avail_count >= need - i)
 258					more_have = need - i;
 259				else
 260					more_have = mdsc->caps_avail_count;
 261
 262				i += more_have;
 263				have += more_have;
 264				mdsc->caps_avail_count -= more_have;
 265				mdsc->caps_reserve_count += more_have;
 266
 267			}
 268			spin_unlock(&mdsc->caps_list_lock);
 269
 270			continue;
 271		}
 272
 273		pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
 274			ctx, need, have + alloc);
 275		err = -ENOMEM;
 276		break;
 277	}
 278
 279	if (!err) {
 280		BUG_ON(have + alloc != need);
 281		ctx->count = need;
 282		ctx->used = 0;
 283	}
 284
 285	spin_lock(&mdsc->caps_list_lock);
 286	mdsc->caps_total_count += alloc;
 287	mdsc->caps_reserve_count += alloc;
 288	list_splice(&newcaps, &mdsc->caps_list);
 289
 290	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 291					 mdsc->caps_reserve_count +
 292					 mdsc->caps_avail_count);
 293
 294	if (err)
 295		__ceph_unreserve_caps(mdsc, have + alloc);
 296
 297	spin_unlock(&mdsc->caps_list_lock);
 298
 
 299	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 300	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 301	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 302	return err;
 303}
 304
 305void ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 306			 struct ceph_cap_reservation *ctx)
 307{
 308	bool reclaim = false;
 309	if (!ctx->count)
 310		return;
 311
 312	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
 313	spin_lock(&mdsc->caps_list_lock);
 314	__ceph_unreserve_caps(mdsc, ctx->count);
 315	ctx->count = 0;
 316
 317	if (mdsc->caps_use_max > 0 &&
 318	    mdsc->caps_use_count > mdsc->caps_use_max)
 319		reclaim = true;
 320	spin_unlock(&mdsc->caps_list_lock);
 321
 322	if (reclaim)
 323		ceph_reclaim_caps_nr(mdsc, ctx->used);
 
 
 
 
 324}
 325
 326struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
 327			      struct ceph_cap_reservation *ctx)
 328{
 329	struct ceph_cap *cap = NULL;
 330
 331	/* temporary, until we do something about cap import/export */
 332	if (!ctx) {
 333		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 334		if (cap) {
 335			spin_lock(&mdsc->caps_list_lock);
 336			mdsc->caps_use_count++;
 337			mdsc->caps_total_count++;
 338			spin_unlock(&mdsc->caps_list_lock);
 339		} else {
 340			spin_lock(&mdsc->caps_list_lock);
 341			if (mdsc->caps_avail_count) {
 342				BUG_ON(list_empty(&mdsc->caps_list));
 343
 344				mdsc->caps_avail_count--;
 345				mdsc->caps_use_count++;
 346				cap = list_first_entry(&mdsc->caps_list,
 347						struct ceph_cap, caps_item);
 348				list_del(&cap->caps_item);
 349
 350				BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 351				       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 352			}
 353			spin_unlock(&mdsc->caps_list_lock);
 354		}
 355
 356		return cap;
 357	}
 358
 359	spin_lock(&mdsc->caps_list_lock);
 360	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
 361	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
 362	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 363	BUG_ON(!ctx->count);
 364	BUG_ON(ctx->count > mdsc->caps_reserve_count);
 365	BUG_ON(list_empty(&mdsc->caps_list));
 366
 367	ctx->count--;
 368	ctx->used++;
 369	mdsc->caps_reserve_count--;
 370	mdsc->caps_use_count++;
 371
 372	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
 373	list_del(&cap->caps_item);
 374
 375	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 376	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 377	spin_unlock(&mdsc->caps_list_lock);
 378	return cap;
 379}
 380
 381void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
 382{
 383	spin_lock(&mdsc->caps_list_lock);
 384	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
 385	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
 386	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 387	mdsc->caps_use_count--;
 388	/*
 389	 * Keep some preallocated caps around (ceph_min_count), to
 390	 * avoid lots of free/alloc churn.
 391	 */
 392	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
 393				      mdsc->caps_min_count) {
 394		mdsc->caps_total_count--;
 395		kmem_cache_free(ceph_cap_cachep, cap);
 396	} else {
 397		mdsc->caps_avail_count++;
 398		list_add(&cap->caps_item, &mdsc->caps_list);
 399	}
 400
 401	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 402	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 403	spin_unlock(&mdsc->caps_list_lock);
 404}
 405
 406void ceph_reservation_status(struct ceph_fs_client *fsc,
 407			     int *total, int *avail, int *used, int *reserved,
 408			     int *min)
 409{
 410	struct ceph_mds_client *mdsc = fsc->mdsc;
 411
 412	spin_lock(&mdsc->caps_list_lock);
 413
 414	if (total)
 415		*total = mdsc->caps_total_count;
 416	if (avail)
 417		*avail = mdsc->caps_avail_count;
 418	if (used)
 419		*used = mdsc->caps_use_count;
 420	if (reserved)
 421		*reserved = mdsc->caps_reserve_count;
 422	if (min)
 423		*min = mdsc->caps_min_count;
 424
 425	spin_unlock(&mdsc->caps_list_lock);
 426}
 427
 428/*
 429 * Find ceph_cap for given mds, if any.
 430 *
 431 * Called with i_ceph_lock held.
 432 */
 433static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 434{
 435	struct ceph_cap *cap;
 436	struct rb_node *n = ci->i_caps.rb_node;
 437
 438	while (n) {
 439		cap = rb_entry(n, struct ceph_cap, ci_node);
 440		if (mds < cap->mds)
 441			n = n->rb_left;
 442		else if (mds > cap->mds)
 443			n = n->rb_right;
 444		else
 445			return cap;
 446	}
 447	return NULL;
 448}
 449
 450struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 451{
 452	struct ceph_cap *cap;
 453
 454	spin_lock(&ci->i_ceph_lock);
 455	cap = __get_cap_for_mds(ci, mds);
 456	spin_unlock(&ci->i_ceph_lock);
 457	return cap;
 458}
 459
 460/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 461 * Called under i_ceph_lock.
 462 */
 463static void __insert_cap_node(struct ceph_inode_info *ci,
 464			      struct ceph_cap *new)
 465{
 466	struct rb_node **p = &ci->i_caps.rb_node;
 467	struct rb_node *parent = NULL;
 468	struct ceph_cap *cap = NULL;
 469
 470	while (*p) {
 471		parent = *p;
 472		cap = rb_entry(parent, struct ceph_cap, ci_node);
 473		if (new->mds < cap->mds)
 474			p = &(*p)->rb_left;
 475		else if (new->mds > cap->mds)
 476			p = &(*p)->rb_right;
 477		else
 478			BUG();
 479	}
 480
 481	rb_link_node(&new->ci_node, parent, p);
 482	rb_insert_color(&new->ci_node, &ci->i_caps);
 483}
 484
 485/*
 486 * (re)set cap hold timeouts, which control the delayed release
 487 * of unused caps back to the MDS.  Should be called on cap use.
 488 */
 489static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
 490			       struct ceph_inode_info *ci)
 491{
 492	struct ceph_mount_options *opt = mdsc->fsc->mount_options;
 493
 494	ci->i_hold_caps_min = round_jiffies(jiffies +
 495					    opt->caps_wanted_delay_min * HZ);
 496	ci->i_hold_caps_max = round_jiffies(jiffies +
 497					    opt->caps_wanted_delay_max * HZ);
 498	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
 499	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
 500}
 501
 502/*
 503 * (Re)queue cap at the end of the delayed cap release list.
 504 *
 505 * If I_FLUSH is set, leave the inode at the front of the list.
 506 *
 507 * Caller holds i_ceph_lock
 508 *    -> we take mdsc->cap_delay_lock
 509 */
 510static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 511				struct ceph_inode_info *ci,
 512				bool set_timeout)
 513{
 
 514	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
 515	     ci->i_ceph_flags, ci->i_hold_caps_max);
 516	if (!mdsc->stopping) {
 517		spin_lock(&mdsc->cap_delay_lock);
 518		if (!list_empty(&ci->i_cap_delay_list)) {
 519			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 520				goto no_change;
 521			list_del_init(&ci->i_cap_delay_list);
 522		}
 523		if (set_timeout)
 524			__cap_set_timeouts(mdsc, ci);
 525		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 526no_change:
 527		spin_unlock(&mdsc->cap_delay_lock);
 528	}
 529}
 530
 531/*
 532 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 533 * indicating we should send a cap message to flush dirty metadata
 534 * asap, and move to the front of the delayed cap list.
 535 */
 536static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 537				      struct ceph_inode_info *ci)
 538{
 539	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
 540	spin_lock(&mdsc->cap_delay_lock);
 541	ci->i_ceph_flags |= CEPH_I_FLUSH;
 542	if (!list_empty(&ci->i_cap_delay_list))
 543		list_del_init(&ci->i_cap_delay_list);
 544	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 545	spin_unlock(&mdsc->cap_delay_lock);
 546}
 547
 548/*
 549 * Cancel delayed work on cap.
 550 *
 551 * Caller must hold i_ceph_lock.
 552 */
 553static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 554			       struct ceph_inode_info *ci)
 555{
 556	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
 557	if (list_empty(&ci->i_cap_delay_list))
 558		return;
 559	spin_lock(&mdsc->cap_delay_lock);
 560	list_del_init(&ci->i_cap_delay_list);
 561	spin_unlock(&mdsc->cap_delay_lock);
 562}
 563
 564/*
 565 * Common issue checks for add_cap, handle_cap_grant.
 566 */
 567static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 568			      unsigned issued)
 569{
 570	unsigned had = __ceph_caps_issued(ci, NULL);
 571
 572	/*
 573	 * Each time we receive FILE_CACHE anew, we increment
 574	 * i_rdcache_gen.
 575	 */
 576	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 577	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) {
 578		ci->i_rdcache_gen++;
 579	}
 580
 581	/*
 582	 * If FILE_SHARED is newly issued, mark dir not complete. We don't
 583	 * know what happened to this directory while we didn't have the cap.
 584	 * If FILE_SHARED is being revoked, also mark dir not complete. It
 585	 * stops on-going cached readdir.
 586	 */
 587	if ((issued & CEPH_CAP_FILE_SHARED) != (had & CEPH_CAP_FILE_SHARED)) {
 588		if (issued & CEPH_CAP_FILE_SHARED)
 589			atomic_inc(&ci->i_shared_gen);
 590		if (S_ISDIR(ci->vfs_inode.i_mode)) {
 591			dout(" marking %p NOT complete\n", &ci->vfs_inode);
 592			__ceph_dir_clear_complete(ci);
 593		}
 594	}
 595}
 596
 597/*
 598 * Add a capability under the given MDS session.
 599 *
 600 * Caller should hold session snap_rwsem (read) and ci->i_ceph_lock
 601 *
 602 * @fmode is the open file mode, if we are opening a file, otherwise
 603 * it is < 0.  (This is so we can atomically add the cap and add an
 604 * open file reference to it.)
 605 */
 606void ceph_add_cap(struct inode *inode,
 607		  struct ceph_mds_session *session, u64 cap_id,
 608		  int fmode, unsigned issued, unsigned wanted,
 609		  unsigned seq, unsigned mseq, u64 realmino, int flags,
 610		  struct ceph_cap **new_cap)
 611{
 612	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 613	struct ceph_inode_info *ci = ceph_inode(inode);
 614	struct ceph_cap *cap;
 615	int mds = session->s_mds;
 616	int actual_wanted;
 617	u32 gen;
 618
 619	lockdep_assert_held(&ci->i_ceph_lock);
 620
 621	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 622	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 623
 624	/*
 625	 * If we are opening the file, include file mode wanted bits
 626	 * in wanted.
 627	 */
 628	if (fmode >= 0)
 629		wanted |= ceph_caps_for_mode(fmode);
 630
 631	spin_lock(&session->s_gen_ttl_lock);
 632	gen = session->s_cap_gen;
 633	spin_unlock(&session->s_gen_ttl_lock);
 634
 635	cap = __get_cap_for_mds(ci, mds);
 636	if (!cap) {
 637		cap = *new_cap;
 638		*new_cap = NULL;
 639
 640		cap->issued = 0;
 641		cap->implemented = 0;
 642		cap->mds = mds;
 643		cap->mds_wanted = 0;
 644		cap->mseq = 0;
 645
 646		cap->ci = ci;
 647		__insert_cap_node(ci, cap);
 648
 649		/* add to session cap list */
 650		cap->session = session;
 651		spin_lock(&session->s_cap_lock);
 652		list_add_tail(&cap->session_caps, &session->s_caps);
 653		session->s_nr_caps++;
 654		spin_unlock(&session->s_cap_lock);
 655	} else {
 656		spin_lock(&session->s_cap_lock);
 657		list_move_tail(&cap->session_caps, &session->s_caps);
 658		spin_unlock(&session->s_cap_lock);
 659
 660		if (cap->cap_gen < gen)
 661			cap->issued = cap->implemented = CEPH_CAP_PIN;
 662
 663		/*
 664		 * auth mds of the inode changed. we received the cap export
 665		 * message, but still haven't received the cap import message.
 666		 * handle_cap_export() updated the new auth MDS' cap.
 667		 *
 668		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 669		 * a message that was send before the cap import message. So
 670		 * don't remove caps.
 671		 */
 672		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 673			WARN_ON(cap != ci->i_auth_cap);
 674			WARN_ON(cap->cap_id != cap_id);
 675			seq = cap->seq;
 676			mseq = cap->mseq;
 677			issued |= cap->issued;
 678			flags |= CEPH_CAP_FLAG_AUTH;
 679		}
 680	}
 681
 682	if (!ci->i_snap_realm ||
 683	    ((flags & CEPH_CAP_FLAG_AUTH) &&
 684	     realmino != (u64)-1 && ci->i_snap_realm->ino != realmino)) {
 685		/*
 686		 * add this inode to the appropriate snap realm
 687		 */
 688		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 689							       realmino);
 690		if (realm) {
 691			struct ceph_snap_realm *oldrealm = ci->i_snap_realm;
 692			if (oldrealm) {
 693				spin_lock(&oldrealm->inodes_with_caps_lock);
 694				list_del_init(&ci->i_snap_realm_item);
 695				spin_unlock(&oldrealm->inodes_with_caps_lock);
 696			}
 697
 698			spin_lock(&realm->inodes_with_caps_lock);
 
 699			list_add(&ci->i_snap_realm_item,
 700				 &realm->inodes_with_caps);
 701			ci->i_snap_realm = realm;
 702			if (realm->ino == ci->i_vino.ino)
 703				realm->inode = inode;
 704			spin_unlock(&realm->inodes_with_caps_lock);
 705
 706			if (oldrealm)
 707				ceph_put_snap_realm(mdsc, oldrealm);
 708		} else {
 709			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 710			       realmino);
 711			WARN_ON(!realm);
 712		}
 713	}
 714
 715	__check_cap_issue(ci, cap, issued);
 716
 717	/*
 718	 * If we are issued caps we don't want, or the mds' wanted
 719	 * value appears to be off, queue a check so we'll release
 720	 * later and/or update the mds wanted value.
 721	 */
 722	actual_wanted = __ceph_caps_wanted(ci);
 723	if ((wanted & ~actual_wanted) ||
 724	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 725		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 726		     ceph_cap_string(issued), ceph_cap_string(wanted),
 727		     ceph_cap_string(actual_wanted));
 728		__cap_delay_requeue(mdsc, ci, true);
 729	}
 730
 731	if (flags & CEPH_CAP_FLAG_AUTH) {
 732		if (!ci->i_auth_cap ||
 733		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 734			ci->i_auth_cap = cap;
 735			cap->mds_wanted = wanted;
 736		}
 737	} else {
 738		WARN_ON(ci->i_auth_cap == cap);
 739	}
 740
 741	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 742	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 743	     ceph_cap_string(issued|cap->issued), seq, mds);
 744	cap->cap_id = cap_id;
 745	cap->issued = issued;
 746	cap->implemented |= issued;
 747	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 748		cap->mds_wanted = wanted;
 749	else
 750		cap->mds_wanted |= wanted;
 751	cap->seq = seq;
 752	cap->issue_seq = seq;
 753	cap->mseq = mseq;
 754	cap->cap_gen = gen;
 755
 756	if (fmode >= 0)
 757		__ceph_get_fmode(ci, fmode);
 758}
 759
 760/*
 761 * Return true if cap has not timed out and belongs to the current
 762 * generation of the MDS session (i.e. has not gone 'stale' due to
 763 * us losing touch with the mds).
 764 */
 765static int __cap_is_valid(struct ceph_cap *cap)
 766{
 767	unsigned long ttl;
 768	u32 gen;
 769
 770	spin_lock(&cap->session->s_gen_ttl_lock);
 771	gen = cap->session->s_cap_gen;
 772	ttl = cap->session->s_cap_ttl;
 773	spin_unlock(&cap->session->s_gen_ttl_lock);
 774
 775	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 776		dout("__cap_is_valid %p cap %p issued %s "
 777		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 778		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 779		return 0;
 780	}
 781
 782	return 1;
 783}
 784
 785/*
 786 * Return set of valid cap bits issued to us.  Note that caps time
 787 * out, and may be invalidated in bulk if the client session times out
 788 * and session->s_cap_gen is bumped.
 789 */
 790int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 791{
 792	int have = ci->i_snap_caps;
 793	struct ceph_cap *cap;
 794	struct rb_node *p;
 795
 796	if (implemented)
 797		*implemented = 0;
 798	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 799		cap = rb_entry(p, struct ceph_cap, ci_node);
 800		if (!__cap_is_valid(cap))
 801			continue;
 802		dout("__ceph_caps_issued %p cap %p issued %s\n",
 803		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 804		have |= cap->issued;
 805		if (implemented)
 806			*implemented |= cap->implemented;
 807	}
 808	/*
 809	 * exclude caps issued by non-auth MDS, but are been revoking
 810	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 811	 * these caps, but the message is delayed.
 812	 */
 813	if (ci->i_auth_cap) {
 814		cap = ci->i_auth_cap;
 815		have &= ~cap->implemented | cap->issued;
 816	}
 817	return have;
 818}
 819
 820/*
 821 * Get cap bits issued by caps other than @ocap
 822 */
 823int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 824{
 825	int have = ci->i_snap_caps;
 826	struct ceph_cap *cap;
 827	struct rb_node *p;
 828
 829	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 830		cap = rb_entry(p, struct ceph_cap, ci_node);
 831		if (cap == ocap)
 832			continue;
 833		if (!__cap_is_valid(cap))
 834			continue;
 835		have |= cap->issued;
 836	}
 837	return have;
 838}
 839
 840/*
 841 * Move a cap to the end of the LRU (oldest caps at list head, newest
 842 * at list tail).
 843 */
 844static void __touch_cap(struct ceph_cap *cap)
 845{
 846	struct ceph_mds_session *s = cap->session;
 847
 848	spin_lock(&s->s_cap_lock);
 849	if (!s->s_cap_iterator) {
 850		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 851		     s->s_mds);
 852		list_move_tail(&cap->session_caps, &s->s_caps);
 853	} else {
 854		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 855		     &cap->ci->vfs_inode, cap, s->s_mds);
 856	}
 857	spin_unlock(&s->s_cap_lock);
 858}
 859
 860/*
 861 * Check if we hold the given mask.  If so, move the cap(s) to the
 862 * front of their respective LRUs.  (This is the preferred way for
 863 * callers to check for caps they want.)
 864 */
 865int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 866{
 867	struct ceph_cap *cap;
 868	struct rb_node *p;
 869	int have = ci->i_snap_caps;
 870
 871	if ((have & mask) == mask) {
 872		dout("__ceph_caps_issued_mask ino 0x%lx snap issued %s"
 873		     " (mask %s)\n", ci->vfs_inode.i_ino,
 874		     ceph_cap_string(have),
 875		     ceph_cap_string(mask));
 876		return 1;
 877	}
 878
 879	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 880		cap = rb_entry(p, struct ceph_cap, ci_node);
 881		if (!__cap_is_valid(cap))
 882			continue;
 883		if ((cap->issued & mask) == mask) {
 884			dout("__ceph_caps_issued_mask ino 0x%lx cap %p issued %s"
 885			     " (mask %s)\n", ci->vfs_inode.i_ino, cap,
 886			     ceph_cap_string(cap->issued),
 887			     ceph_cap_string(mask));
 888			if (touch)
 889				__touch_cap(cap);
 890			return 1;
 891		}
 892
 893		/* does a combination of caps satisfy mask? */
 894		have |= cap->issued;
 895		if ((have & mask) == mask) {
 896			dout("__ceph_caps_issued_mask ino 0x%lx combo issued %s"
 897			     " (mask %s)\n", ci->vfs_inode.i_ino,
 898			     ceph_cap_string(cap->issued),
 899			     ceph_cap_string(mask));
 900			if (touch) {
 901				struct rb_node *q;
 902
 903				/* touch this + preceding caps */
 904				__touch_cap(cap);
 905				for (q = rb_first(&ci->i_caps); q != p;
 906				     q = rb_next(q)) {
 907					cap = rb_entry(q, struct ceph_cap,
 908						       ci_node);
 909					if (!__cap_is_valid(cap))
 910						continue;
 911					__touch_cap(cap);
 912				}
 913			}
 914			return 1;
 915		}
 916	}
 917
 918	return 0;
 919}
 920
 921/*
 922 * Return true if mask caps are currently being revoked by an MDS.
 923 */
 924int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 925			       struct ceph_cap *ocap, int mask)
 926{
 927	struct ceph_cap *cap;
 928	struct rb_node *p;
 929
 930	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 931		cap = rb_entry(p, struct ceph_cap, ci_node);
 932		if (cap != ocap &&
 933		    (cap->implemented & ~cap->issued & mask))
 934			return 1;
 935	}
 936	return 0;
 937}
 938
 939int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 940{
 941	struct inode *inode = &ci->vfs_inode;
 942	int ret;
 943
 944	spin_lock(&ci->i_ceph_lock);
 945	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 946	spin_unlock(&ci->i_ceph_lock);
 947	dout("ceph_caps_revoking %p %s = %d\n", inode,
 948	     ceph_cap_string(mask), ret);
 949	return ret;
 950}
 951
 952int __ceph_caps_used(struct ceph_inode_info *ci)
 953{
 954	int used = 0;
 955	if (ci->i_pin_ref)
 956		used |= CEPH_CAP_PIN;
 957	if (ci->i_rd_ref)
 958		used |= CEPH_CAP_FILE_RD;
 959	if (ci->i_rdcache_ref ||
 960	    (!S_ISDIR(ci->vfs_inode.i_mode) && /* ignore readdir cache */
 961	     ci->vfs_inode.i_data.nrpages))
 962		used |= CEPH_CAP_FILE_CACHE;
 963	if (ci->i_wr_ref)
 964		used |= CEPH_CAP_FILE_WR;
 965	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 966		used |= CEPH_CAP_FILE_BUFFER;
 967	return used;
 968}
 969
 970/*
 971 * wanted, by virtue of open file modes
 972 */
 973int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 974{
 975	int i, bits = 0;
 976	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
 977		if (ci->i_nr_by_mode[i])
 978			bits |= 1 << i;
 979	}
 980	if (bits == 0)
 981		return 0;
 982	return ceph_caps_for_mode(bits >> 1);
 983}
 984
 985/*
 986 * Return caps we have registered with the MDS(s) as 'wanted'.
 987 */
 988int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check)
 989{
 990	struct ceph_cap *cap;
 991	struct rb_node *p;
 992	int mds_wanted = 0;
 993
 994	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 995		cap = rb_entry(p, struct ceph_cap, ci_node);
 996		if (check && !__cap_is_valid(cap))
 997			continue;
 998		if (cap == ci->i_auth_cap)
 999			mds_wanted |= cap->mds_wanted;
1000		else
1001			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
1002	}
1003	return mds_wanted;
1004}
1005
1006/*
1007 * called under i_ceph_lock
1008 */
1009static int __ceph_is_single_caps(struct ceph_inode_info *ci)
1010{
1011	return rb_first(&ci->i_caps) == rb_last(&ci->i_caps);
1012}
1013
1014static int __ceph_is_any_caps(struct ceph_inode_info *ci)
1015{
1016	return !RB_EMPTY_ROOT(&ci->i_caps);
1017}
1018
1019int ceph_is_any_caps(struct inode *inode)
1020{
1021	struct ceph_inode_info *ci = ceph_inode(inode);
1022	int ret;
1023
1024	spin_lock(&ci->i_ceph_lock);
1025	ret = __ceph_is_any_caps(ci);
1026	spin_unlock(&ci->i_ceph_lock);
1027
1028	return ret;
1029}
1030
1031static void drop_inode_snap_realm(struct ceph_inode_info *ci)
1032{
1033	struct ceph_snap_realm *realm = ci->i_snap_realm;
1034	spin_lock(&realm->inodes_with_caps_lock);
1035	list_del_init(&ci->i_snap_realm_item);
1036	ci->i_snap_realm_counter++;
1037	ci->i_snap_realm = NULL;
1038	if (realm->ino == ci->i_vino.ino)
1039		realm->inode = NULL;
1040	spin_unlock(&realm->inodes_with_caps_lock);
1041	ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc,
1042			    realm);
1043}
1044
1045/*
1046 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
1047 *
1048 * caller should hold i_ceph_lock.
1049 * caller will not hold session s_mutex if called from destroy_inode.
1050 */
1051void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
1052{
1053	struct ceph_mds_session *session = cap->session;
1054	struct ceph_inode_info *ci = cap->ci;
1055	struct ceph_mds_client *mdsc =
1056		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1057	int removed = 0;
1058
1059	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
1060
1061	/* remove from inode's cap rbtree, and clear auth cap */
1062	rb_erase(&cap->ci_node, &ci->i_caps);
1063	if (ci->i_auth_cap == cap)
1064		ci->i_auth_cap = NULL;
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			__ceph_queue_cap_release(session, cap);
 
 
1090			removed = 0;
1091		}
1092	} else {
1093		cap->queue_release = 0;
1094	}
1095	cap->cap_ino = ci->i_vino.ino;
1096
1097	spin_unlock(&session->s_cap_lock);
1098
 
 
 
 
 
1099	if (removed)
1100		ceph_put_cap(mdsc, cap);
1101
1102	/* when reconnect denied, we remove session caps forcibly,
1103	 * i_wr_ref can be non-zero. If there are ongoing write,
1104	 * keep i_snap_realm.
1105	 */
1106	if (!__ceph_is_any_caps(ci) && ci->i_wr_ref == 0 && ci->i_snap_realm)
1107		drop_inode_snap_realm(ci);
1108
1109	if (!__ceph_is_any_real_caps(ci))
1110		__cap_delay_cancel(mdsc, ci);
1111}
1112
1113struct cap_msg_args {
1114	struct ceph_mds_session	*session;
1115	u64			ino, cid, follows;
1116	u64			flush_tid, oldest_flush_tid, size, max_size;
1117	u64			xattr_version;
1118	u64			change_attr;
1119	struct ceph_buffer	*xattr_buf;
1120	struct timespec64	atime, mtime, ctime, btime;
1121	int			op, caps, wanted, dirty;
1122	u32			seq, issue_seq, mseq, time_warp_seq;
1123	u32			flags;
1124	kuid_t			uid;
1125	kgid_t			gid;
1126	umode_t			mode;
1127	bool			inline_data;
1128};
1129
1130/*
1131 * Build and send a cap message to the given MDS.
1132 *
1133 * Caller should be holding s_mutex.
1134 */
1135static int send_cap_msg(struct cap_msg_args *arg)
1136{
1137	struct ceph_mds_caps *fc;
1138	struct ceph_msg *msg;
1139	void *p;
1140	size_t extra_len;
1141	struct ceph_osd_client *osdc = &arg->session->s_mdsc->fsc->client->osdc;
1142
1143	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
1144	     " seq %u/%u tid %llu/%llu mseq %u follows %lld size %llu/%llu"
1145	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(arg->op),
1146	     arg->cid, arg->ino, ceph_cap_string(arg->caps),
1147	     ceph_cap_string(arg->wanted), ceph_cap_string(arg->dirty),
1148	     arg->seq, arg->issue_seq, arg->flush_tid, arg->oldest_flush_tid,
1149	     arg->mseq, arg->follows, arg->size, arg->max_size,
1150	     arg->xattr_version,
1151	     arg->xattr_buf ? (int)arg->xattr_buf->vec.iov_len : 0);
1152
1153	/* flock buffer size + inline version + inline data size +
1154	 * osd_epoch_barrier + oldest_flush_tid */
1155	extra_len = 4 + 8 + 4 + 4 + 8 + 4 + 4 + 4 + 8 + 8 + 4;
1156	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc) + extra_len,
1157			   GFP_NOFS, false);
1158	if (!msg)
1159		return -ENOMEM;
1160
1161	msg->hdr.version = cpu_to_le16(10);
1162	msg->hdr.tid = cpu_to_le64(arg->flush_tid);
1163
1164	fc = msg->front.iov_base;
1165	memset(fc, 0, sizeof(*fc));
1166
1167	fc->cap_id = cpu_to_le64(arg->cid);
1168	fc->op = cpu_to_le32(arg->op);
1169	fc->seq = cpu_to_le32(arg->seq);
1170	fc->issue_seq = cpu_to_le32(arg->issue_seq);
1171	fc->migrate_seq = cpu_to_le32(arg->mseq);
1172	fc->caps = cpu_to_le32(arg->caps);
1173	fc->wanted = cpu_to_le32(arg->wanted);
1174	fc->dirty = cpu_to_le32(arg->dirty);
1175	fc->ino = cpu_to_le64(arg->ino);
1176	fc->snap_follows = cpu_to_le64(arg->follows);
1177
1178	fc->size = cpu_to_le64(arg->size);
1179	fc->max_size = cpu_to_le64(arg->max_size);
1180	ceph_encode_timespec64(&fc->mtime, &arg->mtime);
1181	ceph_encode_timespec64(&fc->atime, &arg->atime);
1182	ceph_encode_timespec64(&fc->ctime, &arg->ctime);
1183	fc->time_warp_seq = cpu_to_le32(arg->time_warp_seq);
1184
1185	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, arg->uid));
1186	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, arg->gid));
1187	fc->mode = cpu_to_le32(arg->mode);
1188
1189	fc->xattr_version = cpu_to_le64(arg->xattr_version);
1190	if (arg->xattr_buf) {
1191		msg->middle = ceph_buffer_get(arg->xattr_buf);
1192		fc->xattr_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1193		msg->hdr.middle_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1194	}
1195
1196	p = fc + 1;
1197	/* flock buffer size (version 2) */
1198	ceph_encode_32(&p, 0);
1199	/* inline version (version 4) */
1200	ceph_encode_64(&p, arg->inline_data ? 0 : CEPH_INLINE_NONE);
1201	/* inline data size */
1202	ceph_encode_32(&p, 0);
1203	/*
1204	 * osd_epoch_barrier (version 5)
1205	 * The epoch_barrier is protected osdc->lock, so READ_ONCE here in
1206	 * case it was recently changed
1207	 */
1208	ceph_encode_32(&p, READ_ONCE(osdc->epoch_barrier));
1209	/* oldest_flush_tid (version 6) */
1210	ceph_encode_64(&p, arg->oldest_flush_tid);
1211
1212	/*
1213	 * caller_uid/caller_gid (version 7)
1214	 *
1215	 * Currently, we don't properly track which caller dirtied the caps
1216	 * last, and force a flush of them when there is a conflict. For now,
1217	 * just set this to 0:0, to emulate how the MDS has worked up to now.
1218	 */
1219	ceph_encode_32(&p, 0);
1220	ceph_encode_32(&p, 0);
1221
1222	/* pool namespace (version 8) (mds always ignores this) */
1223	ceph_encode_32(&p, 0);
1224
1225	/* btime and change_attr (version 9) */
1226	ceph_encode_timespec64(p, &arg->btime);
 
 
 
 
 
1227	p += sizeof(struct ceph_timespec);
1228	ceph_encode_64(&p, arg->change_attr);
1229
1230	/* Advisory flags (version 10) */
1231	ceph_encode_32(&p, arg->flags);
1232
1233	ceph_con_send(&arg->session->s_con, msg);
1234	return 0;
1235}
1236
1237/*
1238 * Queue cap releases when an inode is dropped from our cache.
 
1239 */
1240void __ceph_remove_caps(struct ceph_inode_info *ci)
1241{
 
1242	struct rb_node *p;
1243
1244	/* lock i_ceph_lock, because ceph_d_revalidate(..., LOOKUP_RCU)
1245	 * may call __ceph_caps_issued_mask() on a freeing inode. */
1246	spin_lock(&ci->i_ceph_lock);
1247	p = rb_first(&ci->i_caps);
1248	while (p) {
1249		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1250		p = rb_next(p);
1251		__ceph_remove_cap(cap, true);
1252	}
1253	spin_unlock(&ci->i_ceph_lock);
1254}
1255
1256/*
1257 * Send a cap msg on the given inode.  Update our caps state, then
1258 * drop i_ceph_lock and send the message.
1259 *
1260 * Make note of max_size reported/requested from mds, revoked caps
1261 * that have now been implemented.
1262 *
 
 
 
 
1263 * Return non-zero if delayed release, or we experienced an error
1264 * such that the caller should requeue + retry later.
1265 *
1266 * called with i_ceph_lock, then drops it.
1267 * caller should hold snap_rwsem (read), s_mutex.
1268 */
1269static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1270		      int op, int flags, int used, int want, int retain,
1271		      int flushing, u64 flush_tid, u64 oldest_flush_tid)
1272	__releases(cap->ci->i_ceph_lock)
1273{
1274	struct ceph_inode_info *ci = cap->ci;
1275	struct inode *inode = &ci->vfs_inode;
1276	struct ceph_buffer *old_blob = NULL;
1277	struct cap_msg_args arg;
1278	int held, revoking;
1279	int wake = 0;
1280	int delayed = 0;
1281	int ret;
1282
1283	held = cap->issued | cap->implemented;
1284	revoking = cap->implemented & ~cap->issued;
1285	retain &= ~revoking;
 
1286
1287	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1288	     inode, cap, cap->session,
1289	     ceph_cap_string(held), ceph_cap_string(held & retain),
1290	     ceph_cap_string(revoking));
1291	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1292
1293	arg.session = cap->session;
1294
1295	/* don't release wanted unless we've waited a bit. */
1296	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1297	    time_before(jiffies, ci->i_hold_caps_min)) {
1298		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1299		     ceph_cap_string(cap->issued),
1300		     ceph_cap_string(cap->issued & retain),
1301		     ceph_cap_string(cap->mds_wanted),
1302		     ceph_cap_string(want));
1303		want |= cap->mds_wanted;
1304		retain |= cap->issued;
1305		delayed = 1;
1306	}
1307	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1308	if (want & ~cap->mds_wanted) {
1309		/* user space may open/close single file frequently.
1310		 * This avoids droping mds_wanted immediately after
1311		 * requesting new mds_wanted.
1312		 */
1313		__cap_set_timeouts(mdsc, ci);
1314	}
1315
1316	cap->issued &= retain;  /* drop bits we don't want */
1317	if (cap->implemented & ~cap->issued) {
1318		/*
1319		 * Wake up any waiters on wanted -> needed transition.
1320		 * This is due to the weird transition from buffered
1321		 * to sync IO... we need to flush dirty pages _before_
1322		 * allowing sync writes to avoid reordering.
1323		 */
1324		wake = 1;
1325	}
1326	cap->implemented &= cap->issued | used;
1327	cap->mds_wanted = want;
1328
1329	arg.ino = ceph_vino(inode).ino;
1330	arg.cid = cap->cap_id;
1331	arg.follows = flushing ? ci->i_head_snapc->seq : 0;
1332	arg.flush_tid = flush_tid;
1333	arg.oldest_flush_tid = oldest_flush_tid;
1334
1335	arg.size = inode->i_size;
1336	ci->i_reported_size = arg.size;
1337	arg.max_size = ci->i_wanted_max_size;
1338	ci->i_requested_max_size = arg.max_size;
1339
1340	if (flushing & CEPH_CAP_XATTR_EXCL) {
1341		old_blob = __ceph_build_xattrs_blob(ci);
1342		arg.xattr_version = ci->i_xattrs.version;
1343		arg.xattr_buf = ci->i_xattrs.blob;
1344	} else {
1345		arg.xattr_buf = NULL;
1346	}
1347
1348	arg.mtime = inode->i_mtime;
1349	arg.atime = inode->i_atime;
1350	arg.ctime = inode->i_ctime;
1351	arg.btime = ci->i_btime;
1352	arg.change_attr = inode_peek_iversion_raw(inode);
1353
1354	arg.op = op;
1355	arg.caps = cap->implemented;
1356	arg.wanted = want;
1357	arg.dirty = flushing;
1358
1359	arg.seq = cap->seq;
1360	arg.issue_seq = cap->issue_seq;
1361	arg.mseq = cap->mseq;
1362	arg.time_warp_seq = ci->i_time_warp_seq;
1363
1364	arg.uid = inode->i_uid;
1365	arg.gid = inode->i_gid;
1366	arg.mode = inode->i_mode;
1367
1368	arg.inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1369	if (!(flags & CEPH_CLIENT_CAPS_PENDING_CAPSNAP) &&
1370	    !list_empty(&ci->i_cap_snaps)) {
1371		struct ceph_cap_snap *capsnap;
1372		list_for_each_entry_reverse(capsnap, &ci->i_cap_snaps, ci_item) {
1373			if (capsnap->cap_flush.tid)
1374				break;
1375			if (capsnap->need_flush) {
1376				flags |= CEPH_CLIENT_CAPS_PENDING_CAPSNAP;
1377				break;
1378			}
1379		}
1380	}
1381	arg.flags = flags;
1382
1383	spin_unlock(&ci->i_ceph_lock);
1384
1385	ceph_buffer_put(old_blob);
1386
1387	ret = send_cap_msg(&arg);
1388	if (ret < 0) {
1389		dout("error sending cap msg, must requeue %p\n", inode);
1390		delayed = 1;
1391	}
1392
1393	if (wake)
1394		wake_up_all(&ci->i_cap_wq);
1395
1396	return delayed;
1397}
1398
1399static inline int __send_flush_snap(struct inode *inode,
1400				    struct ceph_mds_session *session,
1401				    struct ceph_cap_snap *capsnap,
1402				    u32 mseq, u64 oldest_flush_tid)
1403{
1404	struct cap_msg_args	arg;
1405
1406	arg.session = session;
1407	arg.ino = ceph_vino(inode).ino;
1408	arg.cid = 0;
1409	arg.follows = capsnap->follows;
1410	arg.flush_tid = capsnap->cap_flush.tid;
1411	arg.oldest_flush_tid = oldest_flush_tid;
1412
1413	arg.size = capsnap->size;
1414	arg.max_size = 0;
1415	arg.xattr_version = capsnap->xattr_version;
1416	arg.xattr_buf = capsnap->xattr_blob;
1417
1418	arg.atime = capsnap->atime;
1419	arg.mtime = capsnap->mtime;
1420	arg.ctime = capsnap->ctime;
1421	arg.btime = capsnap->btime;
1422	arg.change_attr = capsnap->change_attr;
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
1593	__ceph_flush_snaps(ci, session);
1594out:
1595	spin_unlock(&ci->i_ceph_lock);
1596
1597	if (psession) {
1598		*psession = session;
1599	} else if (session) {
1600		mutex_unlock(&session->s_mutex);
1601		ceph_put_mds_session(session);
1602	}
1603	/* we flushed them all; remove this inode from the queue */
1604	spin_lock(&mdsc->snap_flush_lock);
1605	list_del_init(&ci->i_snap_flush_item);
1606	spin_unlock(&mdsc->snap_flush_lock);
1607}
1608
1609/*
1610 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1611 * Caller is then responsible for calling __mark_inode_dirty with the
1612 * returned flags value.
1613 */
1614int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask,
1615			   struct ceph_cap_flush **pcf)
1616{
1617	struct ceph_mds_client *mdsc =
1618		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1619	struct inode *inode = &ci->vfs_inode;
1620	int was = ci->i_dirty_caps;
1621	int dirty = 0;
1622
1623	if (!ci->i_auth_cap) {
1624		pr_warn("__mark_dirty_caps %p %llx mask %s, "
1625			"but no auth cap (session was closed?)\n",
1626			inode, ceph_ino(inode), ceph_cap_string(mask));
1627		return 0;
1628	}
1629
1630	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1631	     ceph_cap_string(mask), ceph_cap_string(was),
1632	     ceph_cap_string(was | mask));
1633	ci->i_dirty_caps |= mask;
1634	if (was == 0) {
1635		WARN_ON_ONCE(ci->i_prealloc_cap_flush);
1636		swap(ci->i_prealloc_cap_flush, *pcf);
1637
1638		if (!ci->i_head_snapc) {
1639			WARN_ON_ONCE(!rwsem_is_locked(&mdsc->snap_rwsem));
1640			ci->i_head_snapc = ceph_get_snap_context(
1641				ci->i_snap_realm->cached_context);
1642		}
1643		dout(" inode %p now dirty snapc %p auth cap %p\n",
1644		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
1645		BUG_ON(!list_empty(&ci->i_dirty_item));
1646		spin_lock(&mdsc->cap_dirty_lock);
1647		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1648		spin_unlock(&mdsc->cap_dirty_lock);
1649		if (ci->i_flushing_caps == 0) {
1650			ihold(inode);
1651			dirty |= I_DIRTY_SYNC;
1652		}
1653	} else {
1654		WARN_ON_ONCE(!ci->i_prealloc_cap_flush);
1655	}
1656	BUG_ON(list_empty(&ci->i_dirty_item));
1657	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1658	    (mask & CEPH_CAP_FILE_BUFFER))
1659		dirty |= I_DIRTY_DATASYNC;
1660	__cap_delay_requeue(mdsc, ci, true);
1661	return dirty;
1662}
1663
1664struct ceph_cap_flush *ceph_alloc_cap_flush(void)
1665{
1666	return kmem_cache_alloc(ceph_cap_flush_cachep, GFP_KERNEL);
1667}
1668
1669void ceph_free_cap_flush(struct ceph_cap_flush *cf)
1670{
1671	if (cf)
1672		kmem_cache_free(ceph_cap_flush_cachep, cf);
1673}
1674
1675static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc)
1676{
1677	if (!list_empty(&mdsc->cap_flush_list)) {
1678		struct ceph_cap_flush *cf =
1679			list_first_entry(&mdsc->cap_flush_list,
1680					 struct ceph_cap_flush, g_list);
1681		return cf->tid;
1682	}
1683	return 0;
1684}
1685
1686/*
1687 * Remove cap_flush from the mdsc's or inode's flushing cap list.
1688 * Return true if caller needs to wake up flush waiters.
1689 */
1690static bool __finish_cap_flush(struct ceph_mds_client *mdsc,
1691			       struct ceph_inode_info *ci,
1692			       struct ceph_cap_flush *cf)
1693{
1694	struct ceph_cap_flush *prev;
1695	bool wake = cf->wake;
1696	if (mdsc) {
1697		/* are there older pending cap flushes? */
1698		if (wake && cf->g_list.prev != &mdsc->cap_flush_list) {
1699			prev = list_prev_entry(cf, g_list);
1700			prev->wake = true;
1701			wake = false;
1702		}
1703		list_del(&cf->g_list);
1704	} else if (ci) {
1705		if (wake && cf->i_list.prev != &ci->i_cap_flush_list) {
1706			prev = list_prev_entry(cf, i_list);
1707			prev->wake = true;
1708			wake = false;
1709		}
1710		list_del(&cf->i_list);
1711	} else {
1712		BUG_ON(1);
1713	}
1714	return wake;
1715}
1716
1717/*
1718 * Add dirty inode to the flushing list.  Assigned a seq number so we
1719 * can wait for caps to flush without starving.
1720 *
1721 * Called under i_ceph_lock. Returns the flush tid.
1722 */
1723static u64 __mark_caps_flushing(struct inode *inode,
1724				struct ceph_mds_session *session, bool wake,
1725				u64 *oldest_flush_tid)
1726{
1727	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1728	struct ceph_inode_info *ci = ceph_inode(inode);
1729	struct ceph_cap_flush *cf = NULL;
1730	int flushing;
1731
1732	BUG_ON(ci->i_dirty_caps == 0);
1733	BUG_ON(list_empty(&ci->i_dirty_item));
1734	BUG_ON(!ci->i_prealloc_cap_flush);
1735
1736	flushing = ci->i_dirty_caps;
1737	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1738	     ceph_cap_string(flushing),
1739	     ceph_cap_string(ci->i_flushing_caps),
1740	     ceph_cap_string(ci->i_flushing_caps | flushing));
1741	ci->i_flushing_caps |= flushing;
1742	ci->i_dirty_caps = 0;
1743	dout(" inode %p now !dirty\n", inode);
1744
1745	swap(cf, ci->i_prealloc_cap_flush);
1746	cf->caps = flushing;
1747	cf->wake = wake;
1748
1749	spin_lock(&mdsc->cap_dirty_lock);
1750	list_del_init(&ci->i_dirty_item);
1751
1752	cf->tid = ++mdsc->last_cap_flush_tid;
1753	list_add_tail(&cf->g_list, &mdsc->cap_flush_list);
1754	*oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1755
1756	if (list_empty(&ci->i_flushing_item)) {
1757		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1758		mdsc->num_cap_flushing++;
1759	}
1760	spin_unlock(&mdsc->cap_dirty_lock);
1761
1762	list_add_tail(&cf->i_list, &ci->i_cap_flush_list);
1763
1764	return cf->tid;
 
1765}
1766
1767/*
1768 * try to invalidate mapping pages without blocking.
1769 */
1770static int try_nonblocking_invalidate(struct inode *inode)
1771{
1772	struct ceph_inode_info *ci = ceph_inode(inode);
1773	u32 invalidating_gen = ci->i_rdcache_gen;
1774
1775	spin_unlock(&ci->i_ceph_lock);
1776	invalidate_mapping_pages(&inode->i_data, 0, -1);
1777	spin_lock(&ci->i_ceph_lock);
1778
1779	if (inode->i_data.nrpages == 0 &&
1780	    invalidating_gen == ci->i_rdcache_gen) {
1781		/* success. */
1782		dout("try_nonblocking_invalidate %p success\n", inode);
1783		/* save any racing async invalidate some trouble */
1784		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1785		return 0;
1786	}
1787	dout("try_nonblocking_invalidate %p failed\n", inode);
1788	return -1;
1789}
1790
1791bool __ceph_should_report_size(struct ceph_inode_info *ci)
1792{
1793	loff_t size = ci->vfs_inode.i_size;
1794	/* mds will adjust max size according to the reported size */
1795	if (ci->i_flushing_caps & CEPH_CAP_FILE_WR)
1796		return false;
1797	if (size >= ci->i_max_size)
1798		return true;
1799	/* half of previous max_size increment has been used */
1800	if (ci->i_max_size > ci->i_reported_size &&
1801	    (size << 1) >= ci->i_max_size + ci->i_reported_size)
1802		return true;
1803	return false;
1804}
1805
1806/*
1807 * Swiss army knife function to examine currently used and wanted
1808 * versus held caps.  Release, flush, ack revoked caps to mds as
1809 * appropriate.
1810 *
1811 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1812 *    cap release further.
1813 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1814 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1815 *    further delay.
1816 */
1817void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1818		     struct ceph_mds_session *session)
1819{
1820	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1821	struct ceph_mds_client *mdsc = fsc->mdsc;
1822	struct inode *inode = &ci->vfs_inode;
1823	struct ceph_cap *cap;
1824	u64 flush_tid, oldest_flush_tid;
1825	int file_wanted, used, cap_used;
1826	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1827	int issued, implemented, want, retain, revoking, flushing = 0;
1828	int mds = -1;   /* keep track of how far we've gone through i_caps list
1829			   to avoid an infinite loop on retry */
1830	struct rb_node *p;
1831	int delayed = 0, sent = 0;
1832	bool no_delay = flags & CHECK_CAPS_NODELAY;
1833	bool queue_invalidate = false;
 
1834	bool tried_invalidate = false;
1835
1836	/* if we are unmounting, flush any unused caps immediately. */
1837	if (mdsc->stopping)
1838		no_delay = true;
1839
1840	spin_lock(&ci->i_ceph_lock);
1841
1842	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1843		flags |= CHECK_CAPS_FLUSH;
1844
1845	if (!(flags & CHECK_CAPS_AUTHONLY) ||
1846	    (ci->i_auth_cap && __ceph_is_single_caps(ci)))
1847		__cap_delay_cancel(mdsc, ci);
1848
1849	goto retry_locked;
1850retry:
1851	spin_lock(&ci->i_ceph_lock);
1852retry_locked:
1853	file_wanted = __ceph_caps_file_wanted(ci);
1854	used = __ceph_caps_used(ci);
1855	issued = __ceph_caps_issued(ci, &implemented);
1856	revoking = implemented & ~issued;
1857
1858	want = file_wanted;
1859	retain = file_wanted | used | CEPH_CAP_PIN;
1860	if (!mdsc->stopping && inode->i_nlink > 0) {
1861		if (file_wanted) {
1862			retain |= CEPH_CAP_ANY;       /* be greedy */
1863		} else if (S_ISDIR(inode->i_mode) &&
1864			   (issued & CEPH_CAP_FILE_SHARED) &&
1865			   __ceph_dir_is_complete(ci)) {
1866			/*
1867			 * If a directory is complete, we want to keep
1868			 * the exclusive cap. So that MDS does not end up
1869			 * revoking the shared cap on every create/unlink
1870			 * operation.
1871			 */
1872			if (IS_RDONLY(inode))
1873				want = CEPH_CAP_ANY_SHARED;
1874			else
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			continue;     /* nope, all good */
1985
1986		if (no_delay)
1987			goto ack;
1988
1989		/* delay? */
1990		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1991		    time_before(jiffies, ci->i_hold_caps_max)) {
1992			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1993			     ceph_cap_string(cap->issued),
1994			     ceph_cap_string(cap->issued & retain),
1995			     ceph_cap_string(cap->mds_wanted),
1996			     ceph_cap_string(want));
1997			delayed++;
1998			continue;
1999		}
2000
2001ack:
 
 
 
 
 
2002		if (session && session != cap->session) {
2003			dout("oops, wrong session %p mutex\n", session);
2004			mutex_unlock(&session->s_mutex);
2005			session = NULL;
2006		}
2007		if (!session) {
2008			session = cap->session;
2009			if (mutex_trylock(&session->s_mutex) == 0) {
2010				dout("inverting session/ino locks on %p\n",
2011				     session);
2012				spin_unlock(&ci->i_ceph_lock);
2013				if (took_snap_rwsem) {
2014					up_read(&mdsc->snap_rwsem);
2015					took_snap_rwsem = 0;
2016				}
2017				mutex_lock(&session->s_mutex);
2018				goto retry;
2019			}
2020		}
2021
2022		/* kick flushing and flush snaps before sending normal
2023		 * cap message */
2024		if (cap == ci->i_auth_cap &&
2025		    (ci->i_ceph_flags &
2026		     (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS))) {
2027			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2028				__kick_flushing_caps(mdsc, session, ci, 0);
 
 
 
 
 
 
2029			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2030				__ceph_flush_snaps(ci, session);
2031
2032			goto retry_locked;
2033		}
2034
2035		/* take snap_rwsem after session mutex */
2036		if (!took_snap_rwsem) {
2037			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
2038				dout("inverting snap/in locks on %p\n",
2039				     inode);
2040				spin_unlock(&ci->i_ceph_lock);
2041				down_read(&mdsc->snap_rwsem);
2042				took_snap_rwsem = 1;
2043				goto retry;
2044			}
2045			took_snap_rwsem = 1;
2046		}
2047
2048		if (cap == ci->i_auth_cap && ci->i_dirty_caps) {
2049			flushing = ci->i_dirty_caps;
2050			flush_tid = __mark_caps_flushing(inode, session, false,
2051							 &oldest_flush_tid);
2052		} else {
2053			flushing = 0;
2054			flush_tid = 0;
2055			spin_lock(&mdsc->cap_dirty_lock);
2056			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2057			spin_unlock(&mdsc->cap_dirty_lock);
2058		}
2059
2060		mds = cap->mds;  /* remember mds, so we don't repeat */
2061		sent++;
2062
2063		/* __send_cap drops i_ceph_lock */
2064		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, 0,
2065				cap_used, want, retain, flushing,
2066				flush_tid, oldest_flush_tid);
2067		goto retry; /* retake i_ceph_lock and restart our cap scan. */
2068	}
2069
2070	/* Reschedule delayed caps release if we delayed anything */
2071	if (delayed)
2072		__cap_delay_requeue(mdsc, ci, false);
 
 
 
 
 
 
 
2073
2074	spin_unlock(&ci->i_ceph_lock);
2075
2076	if (queue_invalidate)
2077		ceph_queue_invalidate(inode);
2078
2079	if (session)
2080		mutex_unlock(&session->s_mutex);
2081	if (took_snap_rwsem)
2082		up_read(&mdsc->snap_rwsem);
2083}
2084
2085/*
2086 * Try to flush dirty caps back to the auth mds.
2087 */
2088static int try_flush_caps(struct inode *inode, u64 *ptid)
2089{
2090	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2091	struct ceph_inode_info *ci = ceph_inode(inode);
2092	struct ceph_mds_session *session = NULL;
2093	int flushing = 0;
2094	u64 flush_tid = 0, oldest_flush_tid = 0;
2095
2096retry:
2097	spin_lock(&ci->i_ceph_lock);
2098retry_locked:
 
 
 
2099	if (ci->i_dirty_caps && ci->i_auth_cap) {
2100		struct ceph_cap *cap = ci->i_auth_cap;
 
 
2101		int delayed;
2102
2103		if (session != cap->session) {
2104			spin_unlock(&ci->i_ceph_lock);
2105			if (session)
2106				mutex_unlock(&session->s_mutex);
2107			session = cap->session;
2108			mutex_lock(&session->s_mutex);
2109			goto retry;
2110		}
2111		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {
2112			spin_unlock(&ci->i_ceph_lock);
2113			goto out;
2114		}
2115
2116		if (ci->i_ceph_flags &
2117		    (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS)) {
2118			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2119				__kick_flushing_caps(mdsc, session, ci, 0);
2120			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2121				__ceph_flush_snaps(ci, session);
2122			goto retry_locked;
2123		}
2124
2125		flushing = ci->i_dirty_caps;
2126		flush_tid = __mark_caps_flushing(inode, session, true,
2127						 &oldest_flush_tid);
2128
2129		/* __send_cap drops i_ceph_lock */
2130		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2131				     CEPH_CLIENT_CAPS_SYNC,
2132				     __ceph_caps_used(ci),
2133				     __ceph_caps_wanted(ci),
2134				     (cap->issued | cap->implemented),
2135				     flushing, flush_tid, oldest_flush_tid);
2136
2137		if (delayed) {
2138			spin_lock(&ci->i_ceph_lock);
2139			__cap_delay_requeue(mdsc, ci, true);
2140			spin_unlock(&ci->i_ceph_lock);
2141		}
2142	} else {
2143		if (!list_empty(&ci->i_cap_flush_list)) {
2144			struct ceph_cap_flush *cf =
2145				list_last_entry(&ci->i_cap_flush_list,
2146						struct ceph_cap_flush, i_list);
2147			cf->wake = true;
2148			flush_tid = cf->tid;
2149		}
2150		flushing = ci->i_flushing_caps;
2151		spin_unlock(&ci->i_ceph_lock);
2152	}
2153out:
2154	if (session)
2155		mutex_unlock(&session->s_mutex);
2156
2157	*ptid = flush_tid;
2158	return flushing;
2159}
2160
2161/*
2162 * Return true if we've flushed caps through the given flush_tid.
2163 */
2164static int caps_are_flushed(struct inode *inode, u64 flush_tid)
2165{
2166	struct ceph_inode_info *ci = ceph_inode(inode);
2167	int ret = 1;
2168
2169	spin_lock(&ci->i_ceph_lock);
2170	if (!list_empty(&ci->i_cap_flush_list)) {
2171		struct ceph_cap_flush * cf =
2172			list_first_entry(&ci->i_cap_flush_list,
2173					 struct ceph_cap_flush, i_list);
2174		if (cf->tid <= flush_tid)
2175			ret = 0;
2176	}
2177	spin_unlock(&ci->i_ceph_lock);
2178	return ret;
2179}
2180
2181/*
2182 * wait for any unsafe requests to complete.
2183 */
2184static int unsafe_request_wait(struct inode *inode)
2185{
2186	struct ceph_inode_info *ci = ceph_inode(inode);
2187	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
2188	int ret, err = 0;
2189
2190	spin_lock(&ci->i_unsafe_lock);
2191	if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) {
2192		req1 = list_last_entry(&ci->i_unsafe_dirops,
2193					struct ceph_mds_request,
2194					r_unsafe_dir_item);
2195		ceph_mdsc_get_request(req1);
2196	}
2197	if (!list_empty(&ci->i_unsafe_iops)) {
2198		req2 = list_last_entry(&ci->i_unsafe_iops,
2199					struct ceph_mds_request,
2200					r_unsafe_target_item);
2201		ceph_mdsc_get_request(req2);
2202	}
2203	spin_unlock(&ci->i_unsafe_lock);
2204
2205	dout("unsafe_request_wait %p wait on tid %llu %llu\n",
2206	     inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL);
2207	if (req1) {
2208		ret = !wait_for_completion_timeout(&req1->r_safe_completion,
2209					ceph_timeout_jiffies(req1->r_timeout));
2210		if (ret)
2211			err = -EIO;
2212		ceph_mdsc_put_request(req1);
2213	}
2214	if (req2) {
2215		ret = !wait_for_completion_timeout(&req2->r_safe_completion,
2216					ceph_timeout_jiffies(req2->r_timeout));
2217		if (ret)
2218			err = -EIO;
2219		ceph_mdsc_put_request(req2);
2220	}
2221	return err;
2222}
2223
2224int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2225{
2226	struct ceph_file_info *fi = file->private_data;
2227	struct inode *inode = file->f_mapping->host;
2228	struct ceph_inode_info *ci = ceph_inode(inode);
2229	u64 flush_tid;
2230	int ret, err;
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 (datasync)
2237		goto out;
2238
 
 
2239	dirty = try_flush_caps(inode, &flush_tid);
2240	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
2241
2242	err = unsafe_request_wait(inode);
2243
2244	/*
2245	 * only wait on non-file metadata writeback (the mds
2246	 * can recover size and mtime, so we don't need to
2247	 * wait for that)
2248	 */
2249	if (!err && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
2250		err = wait_event_interruptible(ci->i_cap_wq,
2251					caps_are_flushed(inode, flush_tid));
2252	}
2253
2254	if (err < 0)
2255		ret = err;
2256
2257	if (errseq_check(&ci->i_meta_err, READ_ONCE(fi->meta_err))) {
2258		spin_lock(&file->f_lock);
2259		err = errseq_check_and_advance(&ci->i_meta_err,
2260					       &fi->meta_err);
2261		spin_unlock(&file->f_lock);
2262		if (err < 0)
2263			ret = err;
2264	}
2265out:
2266	dout("fsync %p%s result=%d\n", inode, datasync ? " datasync" : "", ret);
2267	return ret;
2268}
2269
2270/*
2271 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
2272 * queue inode for flush but don't do so immediately, because we can
2273 * get by with fewer MDS messages if we wait for data writeback to
2274 * complete first.
2275 */
2276int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
2277{
2278	struct ceph_inode_info *ci = ceph_inode(inode);
2279	u64 flush_tid;
2280	int err = 0;
2281	int dirty;
2282	int wait = (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync);
2283
2284	dout("write_inode %p wait=%d\n", inode, wait);
2285	if (wait) {
2286		dirty = try_flush_caps(inode, &flush_tid);
2287		if (dirty)
2288			err = wait_event_interruptible(ci->i_cap_wq,
2289				       caps_are_flushed(inode, flush_tid));
2290	} else {
2291		struct ceph_mds_client *mdsc =
2292			ceph_sb_to_client(inode->i_sb)->mdsc;
2293
2294		spin_lock(&ci->i_ceph_lock);
2295		if (__ceph_caps_dirty(ci))
2296			__cap_delay_requeue_front(mdsc, ci);
2297		spin_unlock(&ci->i_ceph_lock);
2298	}
2299	return err;
2300}
2301
2302static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
2303				 struct ceph_mds_session *session,
2304				 struct ceph_inode_info *ci,
2305				 u64 oldest_flush_tid)
2306	__releases(ci->i_ceph_lock)
2307	__acquires(ci->i_ceph_lock)
2308{
2309	struct inode *inode = &ci->vfs_inode;
2310	struct ceph_cap *cap;
2311	struct ceph_cap_flush *cf;
2312	int ret;
2313	u64 first_tid = 0;
2314	u64 last_snap_flush = 0;
2315
2316	ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2317
2318	list_for_each_entry_reverse(cf, &ci->i_cap_flush_list, i_list) {
2319		if (!cf->caps) {
2320			last_snap_flush = cf->tid;
2321			break;
2322		}
2323	}
2324
2325	list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
2326		if (cf->tid < first_tid)
2327			continue;
2328
2329		cap = ci->i_auth_cap;
2330		if (!(cap && cap->session == session)) {
2331			pr_err("%p auth cap %p not mds%d ???\n",
2332			       inode, cap, session->s_mds);
2333			break;
2334		}
2335
2336		first_tid = cf->tid + 1;
2337
2338		if (cf->caps) {
2339			dout("kick_flushing_caps %p cap %p tid %llu %s\n",
2340			     inode, cap, cf->tid, ceph_cap_string(cf->caps));
2341			ci->i_ceph_flags |= CEPH_I_NODELAY;
2342
2343			ret = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2344					 (cf->tid < last_snap_flush ?
2345					  CEPH_CLIENT_CAPS_PENDING_CAPSNAP : 0),
2346					  __ceph_caps_used(ci),
2347					  __ceph_caps_wanted(ci),
2348					  (cap->issued | cap->implemented),
2349					  cf->caps, cf->tid, oldest_flush_tid);
2350			if (ret) {
2351				pr_err("kick_flushing_caps: error sending "
2352					"cap flush, ino (%llx.%llx) "
2353					"tid %llu flushing %s\n",
2354					ceph_vinop(inode), cf->tid,
2355					ceph_cap_string(cf->caps));
2356			}
2357		} else {
2358			struct ceph_cap_snap *capsnap =
2359					container_of(cf, struct ceph_cap_snap,
2360						    cap_flush);
2361			dout("kick_flushing_caps %p capsnap %p tid %llu %s\n",
2362			     inode, capsnap, cf->tid,
2363			     ceph_cap_string(capsnap->dirty));
2364
2365			refcount_inc(&capsnap->nref);
2366			spin_unlock(&ci->i_ceph_lock);
2367
2368			ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
2369						oldest_flush_tid);
2370			if (ret < 0) {
2371				pr_err("kick_flushing_caps: error sending "
2372					"cap flushsnap, ino (%llx.%llx) "
2373					"tid %llu follows %llu\n",
2374					ceph_vinop(inode), cf->tid,
2375					capsnap->follows);
2376			}
2377
2378			ceph_put_cap_snap(capsnap);
2379		}
2380
2381		spin_lock(&ci->i_ceph_lock);
2382	}
2383}
2384
2385void ceph_early_kick_flushing_caps(struct ceph_mds_client *mdsc,
2386				   struct ceph_mds_session *session)
2387{
2388	struct ceph_inode_info *ci;
2389	struct ceph_cap *cap;
2390	u64 oldest_flush_tid;
2391
2392	dout("early_kick_flushing_caps mds%d\n", session->s_mds);
2393
2394	spin_lock(&mdsc->cap_dirty_lock);
2395	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2396	spin_unlock(&mdsc->cap_dirty_lock);
2397
2398	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2399		spin_lock(&ci->i_ceph_lock);
2400		cap = ci->i_auth_cap;
2401		if (!(cap && cap->session == session)) {
2402			pr_err("%p auth cap %p not mds%d ???\n",
2403				&ci->vfs_inode, cap, session->s_mds);
2404			spin_unlock(&ci->i_ceph_lock);
2405			continue;
2406		}
2407
2408
2409		/*
2410		 * if flushing caps were revoked, we re-send the cap flush
2411		 * in client reconnect stage. This guarantees MDS * processes
2412		 * the cap flush message before issuing the flushing caps to
2413		 * other client.
2414		 */
2415		if ((cap->issued & ci->i_flushing_caps) !=
2416		    ci->i_flushing_caps) {
2417			/* encode_caps_cb() also will reset these sequence
2418			 * numbers. make sure sequence numbers in cap flush
2419			 * message match later reconnect message */
2420			cap->seq = 0;
2421			cap->issue_seq = 0;
2422			cap->mseq = 0;
2423			__kick_flushing_caps(mdsc, session, ci,
2424					     oldest_flush_tid);
2425		} else {
2426			ci->i_ceph_flags |= CEPH_I_KICK_FLUSH;
2427		}
2428
2429		spin_unlock(&ci->i_ceph_lock);
2430	}
2431}
2432
2433void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
2434			     struct ceph_mds_session *session)
2435{
2436	struct ceph_inode_info *ci;
2437	struct ceph_cap *cap;
2438	u64 oldest_flush_tid;
2439
2440	dout("kick_flushing_caps mds%d\n", session->s_mds);
2441
2442	spin_lock(&mdsc->cap_dirty_lock);
2443	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2444	spin_unlock(&mdsc->cap_dirty_lock);
2445
2446	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2447		spin_lock(&ci->i_ceph_lock);
2448		cap = ci->i_auth_cap;
2449		if (!(cap && cap->session == session)) {
2450			pr_err("%p auth cap %p not mds%d ???\n",
2451				&ci->vfs_inode, cap, session->s_mds);
2452			spin_unlock(&ci->i_ceph_lock);
2453			continue;
2454		}
2455		if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
 
2456			__kick_flushing_caps(mdsc, session, ci,
2457					     oldest_flush_tid);
2458		}
2459		spin_unlock(&ci->i_ceph_lock);
2460	}
2461}
2462
2463static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
2464				     struct ceph_mds_session *session,
2465				     struct inode *inode)
2466	__releases(ci->i_ceph_lock)
2467{
2468	struct ceph_inode_info *ci = ceph_inode(inode);
2469	struct ceph_cap *cap;
2470
2471	cap = ci->i_auth_cap;
2472	dout("kick_flushing_inode_caps %p flushing %s\n", inode,
2473	     ceph_cap_string(ci->i_flushing_caps));
2474
2475	if (!list_empty(&ci->i_cap_flush_list)) {
2476		u64 oldest_flush_tid;
2477		spin_lock(&mdsc->cap_dirty_lock);
2478		list_move_tail(&ci->i_flushing_item,
2479			       &cap->session->s_cap_flushing);
2480		oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2481		spin_unlock(&mdsc->cap_dirty_lock);
2482
 
2483		__kick_flushing_caps(mdsc, session, ci, oldest_flush_tid);
2484		spin_unlock(&ci->i_ceph_lock);
2485	} else {
2486		spin_unlock(&ci->i_ceph_lock);
2487	}
2488}
2489
2490
2491/*
2492 * Take references to capabilities we hold, so that we don't release
2493 * them to the MDS prematurely.
2494 *
2495 * Protected by i_ceph_lock.
2496 */
2497static void __take_cap_refs(struct ceph_inode_info *ci, int got,
2498			    bool snap_rwsem_locked)
2499{
2500	if (got & CEPH_CAP_PIN)
2501		ci->i_pin_ref++;
2502	if (got & CEPH_CAP_FILE_RD)
2503		ci->i_rd_ref++;
2504	if (got & CEPH_CAP_FILE_CACHE)
2505		ci->i_rdcache_ref++;
2506	if (got & CEPH_CAP_FILE_WR) {
2507		if (ci->i_wr_ref == 0 && !ci->i_head_snapc) {
2508			BUG_ON(!snap_rwsem_locked);
2509			ci->i_head_snapc = ceph_get_snap_context(
2510					ci->i_snap_realm->cached_context);
2511		}
2512		ci->i_wr_ref++;
2513	}
2514	if (got & CEPH_CAP_FILE_BUFFER) {
2515		if (ci->i_wb_ref == 0)
2516			ihold(&ci->vfs_inode);
2517		ci->i_wb_ref++;
2518		dout("__take_cap_refs %p wb %d -> %d (?)\n",
2519		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2520	}
2521}
2522
2523/*
2524 * Try to grab cap references.  Specify those refs we @want, and the
2525 * minimal set we @need.  Also include the larger offset we are writing
2526 * to (when applicable), and check against max_size here as well.
2527 * Note that caller is responsible for ensuring max_size increases are
2528 * requested from the MDS.
2529 *
2530 * Returns 0 if caps were not able to be acquired (yet), a 1 if they were,
2531 * or a negative error code.
2532 *
2533 * FIXME: how does a 0 return differ from -EAGAIN?
2534 */
2535enum {
2536	NON_BLOCKING	= 1,
2537	CHECK_FILELOCK	= 2,
2538};
2539
2540static int try_get_cap_refs(struct inode *inode, int need, int want,
2541			    loff_t endoff, int flags, int *got)
2542{
2543	struct ceph_inode_info *ci = ceph_inode(inode);
2544	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2545	int ret = 0;
2546	int have, implemented;
2547	int file_wanted;
2548	bool snap_rwsem_locked = false;
2549
2550	dout("get_cap_refs %p need %s want %s\n", inode,
2551	     ceph_cap_string(need), ceph_cap_string(want));
2552
2553again:
2554	spin_lock(&ci->i_ceph_lock);
2555
2556	if ((flags & CHECK_FILELOCK) &&
2557	    (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK)) {
2558		dout("try_get_cap_refs %p error filelock\n", inode);
2559		ret = -EIO;
2560		goto out_unlock;
2561	}
2562
2563	/* make sure file is actually open */
2564	file_wanted = __ceph_caps_file_wanted(ci);
2565	if ((file_wanted & need) != need) {
2566		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2567		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2568		ret = -EBADF;
 
2569		goto out_unlock;
2570	}
2571
2572	/* finish pending truncate */
2573	while (ci->i_truncate_pending) {
2574		spin_unlock(&ci->i_ceph_lock);
2575		if (snap_rwsem_locked) {
2576			up_read(&mdsc->snap_rwsem);
2577			snap_rwsem_locked = false;
2578		}
2579		__ceph_do_pending_vmtruncate(inode);
2580		spin_lock(&ci->i_ceph_lock);
2581	}
2582
2583	have = __ceph_caps_issued(ci, &implemented);
2584
2585	if (have & need & CEPH_CAP_FILE_WR) {
2586		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2587			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2588			     inode, endoff, ci->i_max_size);
2589			if (endoff > ci->i_requested_max_size)
2590				ret = -EAGAIN;
 
 
2591			goto out_unlock;
2592		}
2593		/*
2594		 * If a sync write is in progress, we must wait, so that we
2595		 * can get a final snapshot value for size+mtime.
2596		 */
2597		if (__ceph_have_pending_cap_snap(ci)) {
2598			dout("get_cap_refs %p cap_snap_pending\n", inode);
2599			goto out_unlock;
2600		}
2601	}
2602
2603	if ((have & need) == need) {
2604		/*
2605		 * Look at (implemented & ~have & not) so that we keep waiting
2606		 * on transition from wanted -> needed caps.  This is needed
2607		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2608		 * going before a prior buffered writeback happens.
2609		 */
2610		int not = want & ~(have & need);
2611		int revoking = implemented & ~have;
2612		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2613		     inode, ceph_cap_string(have), ceph_cap_string(not),
2614		     ceph_cap_string(revoking));
2615		if ((revoking & not) == 0) {
2616			if (!snap_rwsem_locked &&
2617			    !ci->i_head_snapc &&
2618			    (need & CEPH_CAP_FILE_WR)) {
2619				if (!down_read_trylock(&mdsc->snap_rwsem)) {
2620					/*
2621					 * we can not call down_read() when
2622					 * task isn't in TASK_RUNNING state
2623					 */
2624					if (flags & NON_BLOCKING) {
2625						ret = -EAGAIN;
 
2626						goto out_unlock;
2627					}
2628
2629					spin_unlock(&ci->i_ceph_lock);
2630					down_read(&mdsc->snap_rwsem);
2631					snap_rwsem_locked = true;
2632					goto again;
2633				}
2634				snap_rwsem_locked = true;
2635			}
2636			*got = need | (have & want);
2637			if ((need & CEPH_CAP_FILE_RD) &&
2638			    !(*got & CEPH_CAP_FILE_CACHE))
2639				ceph_disable_fscache_readpage(ci);
2640			__take_cap_refs(ci, *got, true);
2641			ret = 1;
2642		}
2643	} else {
2644		int session_readonly = false;
2645		if ((need & CEPH_CAP_FILE_WR) && ci->i_auth_cap) {
2646			struct ceph_mds_session *s = ci->i_auth_cap->session;
2647			spin_lock(&s->s_cap_lock);
2648			session_readonly = s->s_readonly;
2649			spin_unlock(&s->s_cap_lock);
2650		}
2651		if (session_readonly) {
2652			dout("get_cap_refs %p needed %s but mds%d readonly\n",
2653			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
2654			ret = -EROFS;
 
2655			goto out_unlock;
2656		}
2657
2658		if (ci->i_ceph_flags & CEPH_I_CAP_DROPPED) {
2659			int mds_wanted;
2660			if (READ_ONCE(mdsc->fsc->mount_state) ==
2661			    CEPH_MOUNT_SHUTDOWN) {
2662				dout("get_cap_refs %p forced umount\n", inode);
2663				ret = -EIO;
 
2664				goto out_unlock;
2665			}
2666			mds_wanted = __ceph_caps_mds_wanted(ci, false);
2667			if (need & ~(mds_wanted & need)) {
2668				dout("get_cap_refs %p caps were dropped"
2669				     " (session killed?)\n", inode);
2670				ret = -ESTALE;
 
2671				goto out_unlock;
2672			}
2673			if (!(file_wanted & ~mds_wanted))
 
2674				ci->i_ceph_flags &= ~CEPH_I_CAP_DROPPED;
2675		}
2676
2677		dout("get_cap_refs %p have %s needed %s\n", inode,
2678		     ceph_cap_string(have), ceph_cap_string(need));
2679	}
2680out_unlock:
2681	spin_unlock(&ci->i_ceph_lock);
2682	if (snap_rwsem_locked)
2683		up_read(&mdsc->snap_rwsem);
2684
2685	dout("get_cap_refs %p ret %d got %s\n", inode,
2686	     ret, ceph_cap_string(*got));
2687	return ret;
2688}
2689
2690/*
2691 * Check the offset we are writing up to against our current
2692 * max_size.  If necessary, tell the MDS we want to write to
2693 * a larger offset.
2694 */
2695static void check_max_size(struct inode *inode, loff_t endoff)
2696{
2697	struct ceph_inode_info *ci = ceph_inode(inode);
2698	int check = 0;
2699
2700	/* do we need to explicitly request a larger max_size? */
2701	spin_lock(&ci->i_ceph_lock);
2702	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
2703		dout("write %p at large endoff %llu, req max_size\n",
2704		     inode, endoff);
2705		ci->i_wanted_max_size = endoff;
2706	}
2707	/* duplicate ceph_check_caps()'s logic */
2708	if (ci->i_auth_cap &&
2709	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2710	    ci->i_wanted_max_size > ci->i_max_size &&
2711	    ci->i_wanted_max_size > ci->i_requested_max_size)
2712		check = 1;
2713	spin_unlock(&ci->i_ceph_lock);
2714	if (check)
2715		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2716}
2717
2718int ceph_try_get_caps(struct inode *inode, int need, int want,
2719		      bool nonblock, int *got)
2720{
2721	int ret;
2722
2723	BUG_ON(need & ~CEPH_CAP_FILE_RD);
2724	BUG_ON(want & ~(CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO|CEPH_CAP_FILE_SHARED));
2725	ret = ceph_pool_perm_check(inode, need);
2726	if (ret < 0)
2727		return ret;
2728
2729	ret = try_get_cap_refs(inode, need, want, 0,
2730			       (nonblock ? NON_BLOCKING : 0), got);
2731	return ret == -EAGAIN ? 0 : ret;
 
 
 
 
 
 
2732}
2733
2734/*
2735 * Wait for caps, and take cap references.  If we can't get a WR cap
2736 * due to a small max_size, make sure we check_max_size (and possibly
2737 * ask the mds) so we don't get hung up indefinitely.
2738 */
2739int ceph_get_caps(struct file *filp, int need, int want,
2740		  loff_t endoff, int *got, struct page **pinned_page)
2741{
2742	struct ceph_file_info *fi = filp->private_data;
2743	struct inode *inode = file_inode(filp);
2744	struct ceph_inode_info *ci = ceph_inode(inode);
2745	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
2746	int ret, _got, flags;
2747
2748	ret = ceph_pool_perm_check(inode, need);
2749	if (ret < 0)
2750		return ret;
2751
2752	if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2753	    fi->filp_gen != READ_ONCE(fsc->filp_gen))
2754		return -EBADF;
2755
2756	while (true) {
2757		if (endoff > 0)
2758			check_max_size(inode, endoff);
2759
2760		flags = atomic_read(&fi->num_locks) ? CHECK_FILELOCK : 0;
2761		_got = 0;
2762		ret = try_get_cap_refs(inode, need, want, endoff,
2763				       flags, &_got);
2764		if (ret == -EAGAIN)
2765			continue;
2766		if (!ret) {
 
 
 
2767			DEFINE_WAIT_FUNC(wait, woken_wake_function);
2768			add_wait_queue(&ci->i_cap_wq, &wait);
2769
2770			flags |= NON_BLOCKING;
2771			while (!(ret = try_get_cap_refs(inode, need, want,
2772							endoff, flags, &_got))) {
2773				if (signal_pending(current)) {
2774					ret = -ERESTARTSYS;
2775					break;
2776				}
2777				wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2778			}
2779
2780			remove_wait_queue(&ci->i_cap_wq, &wait);
2781			if (ret == -EAGAIN)
 
2782				continue;
 
 
2783		}
2784
2785		if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2786		    fi->filp_gen != READ_ONCE(fsc->filp_gen)) {
2787			if (ret >= 0 && _got)
2788				ceph_put_cap_refs(ci, _got);
2789			return -EBADF;
2790		}
2791
2792		if (ret < 0) {
2793			if (ret == -ESTALE) {
2794				/* session was killed, try renew caps */
2795				ret = ceph_renew_caps(inode);
2796				if (ret == 0)
2797					continue;
2798			}
2799			return ret;
2800		}
2801
2802		if (ci->i_inline_version != CEPH_INLINE_NONE &&
2803		    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
2804		    i_size_read(inode) > 0) {
2805			struct page *page =
2806				find_get_page(inode->i_mapping, 0);
2807			if (page) {
2808				if (PageUptodate(page)) {
2809					*pinned_page = page;
2810					break;
2811				}
2812				put_page(page);
2813			}
2814			/*
2815			 * drop cap refs first because getattr while
2816			 * holding * caps refs can cause deadlock.
2817			 */
2818			ceph_put_cap_refs(ci, _got);
2819			_got = 0;
2820
2821			/*
2822			 * getattr request will bring inline data into
2823			 * page cache
2824			 */
2825			ret = __ceph_do_getattr(inode, NULL,
2826						CEPH_STAT_CAP_INLINE_DATA,
2827						true);
2828			if (ret < 0)
2829				return ret;
2830			continue;
2831		}
2832		break;
2833	}
2834
2835	if ((_got & CEPH_CAP_FILE_RD) && (_got & CEPH_CAP_FILE_CACHE))
2836		ceph_fscache_revalidate_cookie(ci);
2837
2838	*got = _got;
2839	return 0;
2840}
2841
2842/*
2843 * Take cap refs.  Caller must already know we hold at least one ref
2844 * on the caps in question or we don't know this is safe.
2845 */
2846void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2847{
2848	spin_lock(&ci->i_ceph_lock);
2849	__take_cap_refs(ci, caps, false);
2850	spin_unlock(&ci->i_ceph_lock);
2851}
2852
2853
2854/*
2855 * drop cap_snap that is not associated with any snapshot.
2856 * we don't need to send FLUSHSNAP message for it.
2857 */
2858static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
2859				  struct ceph_cap_snap *capsnap)
2860{
2861	if (!capsnap->need_flush &&
2862	    !capsnap->writing && !capsnap->dirty_pages) {
2863		dout("dropping cap_snap %p follows %llu\n",
2864		     capsnap, capsnap->follows);
2865		BUG_ON(capsnap->cap_flush.tid > 0);
2866		ceph_put_snap_context(capsnap->context);
2867		if (!list_is_last(&capsnap->ci_item, &ci->i_cap_snaps))
2868			ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
2869
2870		list_del(&capsnap->ci_item);
2871		ceph_put_cap_snap(capsnap);
2872		return 1;
2873	}
2874	return 0;
2875}
2876
2877/*
2878 * Release cap refs.
2879 *
2880 * If we released the last ref on any given cap, call ceph_check_caps
2881 * to release (or schedule a release).
2882 *
2883 * If we are releasing a WR cap (from a sync write), finalize any affected
2884 * cap_snap, and wake up any waiters.
2885 */
2886void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2887{
2888	struct inode *inode = &ci->vfs_inode;
2889	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2890
2891	spin_lock(&ci->i_ceph_lock);
2892	if (had & CEPH_CAP_PIN)
2893		--ci->i_pin_ref;
2894	if (had & CEPH_CAP_FILE_RD)
2895		if (--ci->i_rd_ref == 0)
2896			last++;
2897	if (had & CEPH_CAP_FILE_CACHE)
2898		if (--ci->i_rdcache_ref == 0)
2899			last++;
2900	if (had & CEPH_CAP_FILE_BUFFER) {
2901		if (--ci->i_wb_ref == 0) {
2902			last++;
2903			put++;
2904		}
2905		dout("put_cap_refs %p wb %d -> %d (?)\n",
2906		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2907	}
2908	if (had & CEPH_CAP_FILE_WR)
2909		if (--ci->i_wr_ref == 0) {
2910			last++;
2911			if (__ceph_have_pending_cap_snap(ci)) {
2912				struct ceph_cap_snap *capsnap =
2913					list_last_entry(&ci->i_cap_snaps,
2914							struct ceph_cap_snap,
2915							ci_item);
2916				capsnap->writing = 0;
2917				if (ceph_try_drop_cap_snap(ci, capsnap))
2918					put++;
2919				else if (__ceph_finish_cap_snap(ci, capsnap))
2920					flushsnaps = 1;
2921				wake = 1;
2922			}
2923			if (ci->i_wrbuffer_ref_head == 0 &&
2924			    ci->i_dirty_caps == 0 &&
2925			    ci->i_flushing_caps == 0) {
2926				BUG_ON(!ci->i_head_snapc);
2927				ceph_put_snap_context(ci->i_head_snapc);
2928				ci->i_head_snapc = NULL;
2929			}
2930			/* see comment in __ceph_remove_cap() */
2931			if (!__ceph_is_any_caps(ci) && ci->i_snap_realm)
2932				drop_inode_snap_realm(ci);
2933		}
2934	spin_unlock(&ci->i_ceph_lock);
2935
2936	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2937	     last ? " last" : "", put ? " put" : "");
2938
2939	if (last && !flushsnaps)
2940		ceph_check_caps(ci, 0, NULL);
2941	else if (flushsnaps)
2942		ceph_flush_snaps(ci, NULL);
2943	if (wake)
2944		wake_up_all(&ci->i_cap_wq);
2945	while (put-- > 0)
2946		iput(inode);
2947}
2948
2949/*
2950 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2951 * context.  Adjust per-snap dirty page accounting as appropriate.
2952 * Once all dirty data for a cap_snap is flushed, flush snapped file
2953 * metadata back to the MDS.  If we dropped the last ref, call
2954 * ceph_check_caps.
2955 */
2956void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2957				struct ceph_snap_context *snapc)
2958{
2959	struct inode *inode = &ci->vfs_inode;
2960	struct ceph_cap_snap *capsnap = NULL;
2961	int put = 0;
2962	bool last = false;
2963	bool found = false;
2964	bool flush_snaps = false;
2965	bool complete_capsnap = false;
2966
2967	spin_lock(&ci->i_ceph_lock);
2968	ci->i_wrbuffer_ref -= nr;
2969	if (ci->i_wrbuffer_ref == 0) {
2970		last = true;
2971		put++;
2972	}
2973
2974	if (ci->i_head_snapc == snapc) {
2975		ci->i_wrbuffer_ref_head -= nr;
2976		if (ci->i_wrbuffer_ref_head == 0 &&
2977		    ci->i_wr_ref == 0 &&
2978		    ci->i_dirty_caps == 0 &&
2979		    ci->i_flushing_caps == 0) {
2980			BUG_ON(!ci->i_head_snapc);
2981			ceph_put_snap_context(ci->i_head_snapc);
2982			ci->i_head_snapc = NULL;
2983		}
2984		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2985		     inode,
2986		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2987		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2988		     last ? " LAST" : "");
2989	} else {
2990		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2991			if (capsnap->context == snapc) {
2992				found = true;
2993				break;
2994			}
2995		}
2996		BUG_ON(!found);
2997		capsnap->dirty_pages -= nr;
2998		if (capsnap->dirty_pages == 0) {
2999			complete_capsnap = true;
3000			if (!capsnap->writing) {
3001				if (ceph_try_drop_cap_snap(ci, capsnap)) {
3002					put++;
3003				} else {
3004					ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
3005					flush_snaps = true;
3006				}
3007			}
3008		}
3009		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
3010		     " snap %lld %d/%d -> %d/%d %s%s\n",
3011		     inode, capsnap, capsnap->context->seq,
3012		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
3013		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
3014		     last ? " (wrbuffer last)" : "",
3015		     complete_capsnap ? " (complete capsnap)" : "");
3016	}
3017
3018	spin_unlock(&ci->i_ceph_lock);
3019
3020	if (last) {
3021		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
3022	} else if (flush_snaps) {
3023		ceph_flush_snaps(ci, NULL);
3024	}
3025	if (complete_capsnap)
3026		wake_up_all(&ci->i_cap_wq);
3027	while (put-- > 0) {
3028		/* avoid calling iput_final() in osd dispatch threads */
3029		ceph_async_iput(inode);
3030	}
3031}
3032
3033/*
3034 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
3035 */
3036static void invalidate_aliases(struct inode *inode)
3037{
3038	struct dentry *dn, *prev = NULL;
3039
3040	dout("invalidate_aliases inode %p\n", inode);
3041	d_prune_aliases(inode);
3042	/*
3043	 * For non-directory inode, d_find_alias() only returns
3044	 * hashed dentry. After calling d_invalidate(), the
3045	 * dentry becomes unhashed.
3046	 *
3047	 * For directory inode, d_find_alias() can return
3048	 * unhashed dentry. But directory inode should have
3049	 * one alias at most.
3050	 */
3051	while ((dn = d_find_alias(inode))) {
3052		if (dn == prev) {
3053			dput(dn);
3054			break;
3055		}
3056		d_invalidate(dn);
3057		if (prev)
3058			dput(prev);
3059		prev = dn;
3060	}
3061	if (prev)
3062		dput(prev);
3063}
3064
3065struct cap_extra_info {
3066	struct ceph_string *pool_ns;
3067	/* inline data */
3068	u64 inline_version;
3069	void *inline_data;
3070	u32 inline_len;
3071	/* dirstat */
3072	bool dirstat_valid;
3073	u64 nfiles;
3074	u64 nsubdirs;
3075	u64 change_attr;
3076	/* currently issued */
3077	int issued;
3078	struct timespec64 btime;
3079};
3080
3081/*
3082 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
3083 * actually be a revocation if it specifies a smaller cap set.)
3084 *
3085 * caller holds s_mutex and i_ceph_lock, we drop both.
3086 */
3087static void handle_cap_grant(struct inode *inode,
 
 
 
 
3088			     struct ceph_mds_session *session,
3089			     struct ceph_cap *cap,
3090			     struct ceph_mds_caps *grant,
3091			     struct ceph_buffer *xattr_buf,
3092			     struct cap_extra_info *extra_info)
3093	__releases(ci->i_ceph_lock)
3094	__releases(session->s_mdsc->snap_rwsem)
3095{
3096	struct ceph_inode_info *ci = ceph_inode(inode);
 
3097	int seq = le32_to_cpu(grant->seq);
3098	int newcaps = le32_to_cpu(grant->caps);
3099	int used, wanted, dirty;
3100	u64 size = le64_to_cpu(grant->size);
3101	u64 max_size = le64_to_cpu(grant->max_size);
3102	unsigned char check_caps = 0;
3103	bool was_stale = cap->cap_gen < session->s_cap_gen;
3104	bool wake = false;
3105	bool writeback = false;
3106	bool queue_trunc = false;
3107	bool queue_invalidate = false;
3108	bool deleted_inode = false;
3109	bool fill_inline = false;
3110
3111	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
3112	     inode, cap, session->s_mds, seq, ceph_cap_string(newcaps));
3113	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
3114		inode->i_size);
3115
3116
3117	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3118	 * If CACHE is being revoked, and we have no dirty buffers,
3119	 * try to invalidate (once).  (If there are dirty buffers, we
3120	 * will invalidate _after_ writeback.)
3121	 */
3122	if (!S_ISDIR(inode->i_mode) && /* don't invalidate readdir cache */
3123	    ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
3124	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3125	    !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
3126		if (try_nonblocking_invalidate(inode)) {
3127			/* there were locked pages.. invalidate later
3128			   in a separate thread. */
3129			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
3130				queue_invalidate = true;
3131				ci->i_rdcache_revoking = ci->i_rdcache_gen;
3132			}
3133		}
3134	}
3135
3136	if (was_stale)
3137		cap->issued = cap->implemented = CEPH_CAP_PIN;
3138
3139	/*
3140	 * auth mds of the inode changed. we received the cap export message,
3141	 * but still haven't received the cap import message. handle_cap_export
3142	 * updated the new auth MDS' cap.
3143	 *
3144	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
3145	 * that was sent before the cap import message. So don't remove caps.
3146	 */
3147	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
3148		WARN_ON(cap != ci->i_auth_cap);
3149		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
3150		seq = cap->seq;
3151		newcaps |= cap->issued;
3152	}
3153
3154	/* side effects now are allowed */
3155	cap->cap_gen = session->s_cap_gen;
3156	cap->seq = seq;
3157
3158	__check_cap_issue(ci, cap, newcaps);
3159
3160	inode_set_max_iversion_raw(inode, extra_info->change_attr);
3161
3162	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
3163	    (extra_info->issued & CEPH_CAP_AUTH_EXCL) == 0) {
3164		inode->i_mode = le32_to_cpu(grant->mode);
3165		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
3166		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
3167		ci->i_btime = extra_info->btime;
3168		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
3169		     from_kuid(&init_user_ns, inode->i_uid),
3170		     from_kgid(&init_user_ns, inode->i_gid));
3171	}
3172
3173	if ((newcaps & CEPH_CAP_LINK_SHARED) &&
3174	    (extra_info->issued & CEPH_CAP_LINK_EXCL) == 0) {
3175		set_nlink(inode, le32_to_cpu(grant->nlink));
3176		if (inode->i_nlink == 0 &&
3177		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
3178			deleted_inode = true;
3179	}
3180
3181	if ((extra_info->issued & CEPH_CAP_XATTR_EXCL) == 0 &&
3182	    grant->xattr_len) {
3183		int len = le32_to_cpu(grant->xattr_len);
3184		u64 version = le64_to_cpu(grant->xattr_version);
3185
3186		if (version > ci->i_xattrs.version) {
3187			dout(" got new xattrs v%llu on %p len %d\n",
3188			     version, inode, len);
3189			if (ci->i_xattrs.blob)
3190				ceph_buffer_put(ci->i_xattrs.blob);
3191			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
3192			ci->i_xattrs.version = version;
3193			ceph_forget_all_cached_acls(inode);
3194			ceph_security_invalidate_secctx(inode);
3195		}
3196	}
3197
3198	if (newcaps & CEPH_CAP_ANY_RD) {
3199		struct timespec64 mtime, atime, ctime;
3200		/* ctime/mtime/atime? */
3201		ceph_decode_timespec64(&mtime, &grant->mtime);
3202		ceph_decode_timespec64(&atime, &grant->atime);
3203		ceph_decode_timespec64(&ctime, &grant->ctime);
3204		ceph_fill_file_time(inode, extra_info->issued,
3205				    le32_to_cpu(grant->time_warp_seq),
3206				    &ctime, &mtime, &atime);
3207	}
3208
3209	if ((newcaps & CEPH_CAP_FILE_SHARED) && extra_info->dirstat_valid) {
3210		ci->i_files = extra_info->nfiles;
3211		ci->i_subdirs = extra_info->nsubdirs;
3212	}
3213
3214	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
3215		/* file layout may have changed */
3216		s64 old_pool = ci->i_layout.pool_id;
3217		struct ceph_string *old_ns;
3218
3219		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
3220		old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
3221					lockdep_is_held(&ci->i_ceph_lock));
3222		rcu_assign_pointer(ci->i_layout.pool_ns, extra_info->pool_ns);
3223
3224		if (ci->i_layout.pool_id != old_pool ||
3225		    extra_info->pool_ns != old_ns)
3226			ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
3227
3228		extra_info->pool_ns = old_ns;
3229
3230		/* size/truncate_seq? */
3231		queue_trunc = ceph_fill_file_size(inode, extra_info->issued,
3232					le32_to_cpu(grant->truncate_seq),
3233					le64_to_cpu(grant->truncate_size),
3234					size);
3235	}
3236
3237	if (ci->i_auth_cap == cap && (newcaps & CEPH_CAP_ANY_FILE_WR)) {
3238		if (max_size != ci->i_max_size) {
3239			dout("max_size %lld -> %llu\n",
3240			     ci->i_max_size, max_size);
3241			ci->i_max_size = max_size;
3242			if (max_size >= ci->i_wanted_max_size) {
3243				ci->i_wanted_max_size = 0;  /* reset */
3244				ci->i_requested_max_size = 0;
3245			}
3246			wake = true;
3247		} else if (ci->i_wanted_max_size > ci->i_max_size &&
3248			   ci->i_wanted_max_size > ci->i_requested_max_size) {
3249			/* CEPH_CAP_OP_IMPORT */
3250			wake = true;
3251		}
3252	}
3253
3254	/* check cap bits */
3255	wanted = __ceph_caps_wanted(ci);
3256	used = __ceph_caps_used(ci);
3257	dirty = __ceph_caps_dirty(ci);
3258	dout(" my wanted = %s, used = %s, dirty %s\n",
3259	     ceph_cap_string(wanted),
3260	     ceph_cap_string(used),
3261	     ceph_cap_string(dirty));
3262
3263	if ((was_stale || le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) &&
3264	    (wanted & ~(cap->mds_wanted | newcaps))) {
3265		/*
3266		 * If mds is importing cap, prior cap messages that update
3267		 * 'wanted' may get dropped by mds (migrate seq mismatch).
3268		 *
3269		 * We don't send cap message to update 'wanted' if what we
3270		 * want are already issued. If mds revokes caps, cap message
3271		 * that releases caps also tells mds what we want. But if
3272		 * caps got revoked by mds forcedly (session stale). We may
3273		 * haven't told mds what we want.
3274		 */
3275		check_caps = 1;
3276	}
3277
3278	/* revocation, grant, or no-op? */
3279	if (cap->issued & ~newcaps) {
3280		int revoking = cap->issued & ~newcaps;
3281
3282		dout("revocation: %s -> %s (revoking %s)\n",
3283		     ceph_cap_string(cap->issued),
3284		     ceph_cap_string(newcaps),
3285		     ceph_cap_string(revoking));
3286		if (revoking & used & CEPH_CAP_FILE_BUFFER)
3287			writeback = true;  /* initiate writeback; will delay ack */
3288		else if (revoking == CEPH_CAP_FILE_CACHE &&
3289			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3290			 queue_invalidate)
3291			; /* do nothing yet, invalidation will be queued */
3292		else if (cap == ci->i_auth_cap)
3293			check_caps = 1; /* check auth cap only */
3294		else
3295			check_caps = 2; /* check all caps */
3296		cap->issued = newcaps;
3297		cap->implemented |= newcaps;
3298	} else if (cap->issued == newcaps) {
3299		dout("caps unchanged: %s -> %s\n",
3300		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
3301	} else {
3302		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
3303		     ceph_cap_string(newcaps));
3304		/* non-auth MDS is revoking the newly grant caps ? */
3305		if (cap == ci->i_auth_cap &&
3306		    __ceph_caps_revoking_other(ci, cap, newcaps))
3307		    check_caps = 2;
3308
3309		cap->issued = newcaps;
3310		cap->implemented |= newcaps; /* add bits only, to
3311					      * avoid stepping on a
3312					      * pending revocation */
3313		wake = true;
3314	}
3315	BUG_ON(cap->issued & ~cap->implemented);
3316
3317	if (extra_info->inline_version > 0 &&
3318	    extra_info->inline_version >= ci->i_inline_version) {
3319		ci->i_inline_version = extra_info->inline_version;
3320		if (ci->i_inline_version != CEPH_INLINE_NONE &&
3321		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
3322			fill_inline = true;
3323	}
3324
3325	if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
3326		if (newcaps & ~extra_info->issued)
3327			wake = true;
3328		kick_flushing_inode_caps(session->s_mdsc, session, inode);
3329		up_read(&session->s_mdsc->snap_rwsem);
3330	} else {
3331		spin_unlock(&ci->i_ceph_lock);
3332	}
3333
3334	if (fill_inline)
3335		ceph_fill_inline_data(inode, NULL, extra_info->inline_data,
3336				      extra_info->inline_len);
3337
3338	if (queue_trunc)
3339		ceph_queue_vmtruncate(inode);
3340
3341	if (writeback)
3342		/*
3343		 * queue inode for writeback: we can't actually call
3344		 * filemap_write_and_wait, etc. from message handler
3345		 * context.
3346		 */
3347		ceph_queue_writeback(inode);
3348	if (queue_invalidate)
3349		ceph_queue_invalidate(inode);
3350	if (deleted_inode)
3351		invalidate_aliases(inode);
3352	if (wake)
3353		wake_up_all(&ci->i_cap_wq);
3354
3355	if (check_caps == 1)
3356		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
3357				session);
3358	else if (check_caps == 2)
3359		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
3360	else
3361		mutex_unlock(&session->s_mutex);
3362}
3363
3364/*
3365 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
3366 * MDS has been safely committed.
3367 */
3368static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
3369				 struct ceph_mds_caps *m,
3370				 struct ceph_mds_session *session,
3371				 struct ceph_cap *cap)
3372	__releases(ci->i_ceph_lock)
3373{
3374	struct ceph_inode_info *ci = ceph_inode(inode);
3375	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3376	struct ceph_cap_flush *cf, *tmp_cf;
3377	LIST_HEAD(to_remove);
3378	unsigned seq = le32_to_cpu(m->seq);
3379	int dirty = le32_to_cpu(m->dirty);
3380	int cleaned = 0;
3381	bool drop = false;
3382	bool wake_ci = false;
3383	bool wake_mdsc = false;
3384
3385	list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) {
3386		if (cf->tid == flush_tid)
3387			cleaned = cf->caps;
3388		if (cf->caps == 0) /* capsnap */
3389			continue;
3390		if (cf->tid <= flush_tid) {
3391			if (__finish_cap_flush(NULL, ci, cf))
3392				wake_ci = true;
3393			list_add_tail(&cf->i_list, &to_remove);
3394		} else {
3395			cleaned &= ~cf->caps;
3396			if (!cleaned)
3397				break;
3398		}
3399	}
3400
3401	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
3402	     " flushing %s -> %s\n",
3403	     inode, session->s_mds, seq, ceph_cap_string(dirty),
3404	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
3405	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
3406
3407	if (list_empty(&to_remove) && !cleaned)
3408		goto out;
3409
3410	ci->i_flushing_caps &= ~cleaned;
3411
3412	spin_lock(&mdsc->cap_dirty_lock);
3413
3414	list_for_each_entry(cf, &to_remove, i_list) {
3415		if (__finish_cap_flush(mdsc, NULL, cf))
3416			wake_mdsc = true;
3417	}
3418
3419	if (ci->i_flushing_caps == 0) {
3420		if (list_empty(&ci->i_cap_flush_list)) {
3421			list_del_init(&ci->i_flushing_item);
3422			if (!list_empty(&session->s_cap_flushing)) {
3423				dout(" mds%d still flushing cap on %p\n",
3424				     session->s_mds,
3425				     &list_first_entry(&session->s_cap_flushing,
3426						struct ceph_inode_info,
3427						i_flushing_item)->vfs_inode);
3428			}
3429		}
3430		mdsc->num_cap_flushing--;
3431		dout(" inode %p now !flushing\n", inode);
3432
3433		if (ci->i_dirty_caps == 0) {
3434			dout(" inode %p now clean\n", inode);
3435			BUG_ON(!list_empty(&ci->i_dirty_item));
3436			drop = true;
3437			if (ci->i_wr_ref == 0 &&
3438			    ci->i_wrbuffer_ref_head == 0) {
3439				BUG_ON(!ci->i_head_snapc);
3440				ceph_put_snap_context(ci->i_head_snapc);
3441				ci->i_head_snapc = NULL;
3442			}
3443		} else {
3444			BUG_ON(list_empty(&ci->i_dirty_item));
3445		}
3446	}
3447	spin_unlock(&mdsc->cap_dirty_lock);
3448
3449out:
3450	spin_unlock(&ci->i_ceph_lock);
3451
3452	while (!list_empty(&to_remove)) {
3453		cf = list_first_entry(&to_remove,
3454				      struct ceph_cap_flush, i_list);
3455		list_del(&cf->i_list);
3456		ceph_free_cap_flush(cf);
3457	}
3458
3459	if (wake_ci)
3460		wake_up_all(&ci->i_cap_wq);
3461	if (wake_mdsc)
3462		wake_up_all(&mdsc->cap_flushing_wq);
3463	if (drop)
3464		iput(inode);
3465}
3466
3467/*
3468 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
3469 * throw away our cap_snap.
3470 *
3471 * Caller hold s_mutex.
3472 */
3473static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
3474				     struct ceph_mds_caps *m,
3475				     struct ceph_mds_session *session)
3476{
3477	struct ceph_inode_info *ci = ceph_inode(inode);
3478	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3479	u64 follows = le64_to_cpu(m->snap_follows);
3480	struct ceph_cap_snap *capsnap;
3481	bool flushed = false;
3482	bool wake_ci = false;
3483	bool wake_mdsc = false;
3484
3485	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
3486	     inode, ci, session->s_mds, follows);
3487
3488	spin_lock(&ci->i_ceph_lock);
3489	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
3490		if (capsnap->follows == follows) {
3491			if (capsnap->cap_flush.tid != flush_tid) {
3492				dout(" cap_snap %p follows %lld tid %lld !="
3493				     " %lld\n", capsnap, follows,
3494				     flush_tid, capsnap->cap_flush.tid);
3495				break;
3496			}
3497			flushed = true;
3498			break;
3499		} else {
3500			dout(" skipping cap_snap %p follows %lld\n",
3501			     capsnap, capsnap->follows);
3502		}
3503	}
3504	if (flushed) {
3505		WARN_ON(capsnap->dirty_pages || capsnap->writing);
3506		dout(" removing %p cap_snap %p follows %lld\n",
3507		     inode, capsnap, follows);
3508		list_del(&capsnap->ci_item);
3509		if (__finish_cap_flush(NULL, ci, &capsnap->cap_flush))
3510			wake_ci = true;
3511
3512		spin_lock(&mdsc->cap_dirty_lock);
3513
3514		if (list_empty(&ci->i_cap_flush_list))
3515			list_del_init(&ci->i_flushing_item);
3516
3517		if (__finish_cap_flush(mdsc, NULL, &capsnap->cap_flush))
3518			wake_mdsc = true;
3519
3520		spin_unlock(&mdsc->cap_dirty_lock);
3521	}
3522	spin_unlock(&ci->i_ceph_lock);
3523	if (flushed) {
3524		ceph_put_snap_context(capsnap->context);
3525		ceph_put_cap_snap(capsnap);
3526		if (wake_ci)
3527			wake_up_all(&ci->i_cap_wq);
3528		if (wake_mdsc)
3529			wake_up_all(&mdsc->cap_flushing_wq);
3530		iput(inode);
3531	}
3532}
3533
3534/*
3535 * Handle TRUNC from MDS, indicating file truncation.
3536 *
3537 * caller hold s_mutex.
3538 */
3539static void handle_cap_trunc(struct inode *inode,
3540			     struct ceph_mds_caps *trunc,
3541			     struct ceph_mds_session *session)
3542	__releases(ci->i_ceph_lock)
3543{
3544	struct ceph_inode_info *ci = ceph_inode(inode);
3545	int mds = session->s_mds;
3546	int seq = le32_to_cpu(trunc->seq);
3547	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
3548	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
3549	u64 size = le64_to_cpu(trunc->size);
3550	int implemented = 0;
3551	int dirty = __ceph_caps_dirty(ci);
3552	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
3553	int queue_trunc = 0;
3554
3555	issued |= implemented | dirty;
3556
3557	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
3558	     inode, mds, seq, truncate_size, truncate_seq);
3559	queue_trunc = ceph_fill_file_size(inode, issued,
3560					  truncate_seq, truncate_size, size);
3561	spin_unlock(&ci->i_ceph_lock);
3562
3563	if (queue_trunc)
3564		ceph_queue_vmtruncate(inode);
3565}
3566
3567/*
3568 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
3569 * different one.  If we are the most recent migration we've seen (as
3570 * indicated by mseq), make note of the migrating cap bits for the
3571 * duration (until we see the corresponding IMPORT).
3572 *
3573 * caller holds s_mutex
3574 */
3575static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
3576			      struct ceph_mds_cap_peer *ph,
3577			      struct ceph_mds_session *session)
3578{
3579	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
3580	struct ceph_mds_session *tsession = NULL;
3581	struct ceph_cap *cap, *tcap, *new_cap = NULL;
3582	struct ceph_inode_info *ci = ceph_inode(inode);
3583	u64 t_cap_id;
3584	unsigned mseq = le32_to_cpu(ex->migrate_seq);
3585	unsigned t_seq, t_mseq;
3586	int target, issued;
3587	int mds = session->s_mds;
3588
3589	if (ph) {
3590		t_cap_id = le64_to_cpu(ph->cap_id);
3591		t_seq = le32_to_cpu(ph->seq);
3592		t_mseq = le32_to_cpu(ph->mseq);
3593		target = le32_to_cpu(ph->mds);
3594	} else {
3595		t_cap_id = t_seq = t_mseq = 0;
3596		target = -1;
3597	}
3598
3599	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
3600	     inode, ci, mds, mseq, target);
3601retry:
3602	spin_lock(&ci->i_ceph_lock);
3603	cap = __get_cap_for_mds(ci, mds);
3604	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
3605		goto out_unlock;
3606
3607	if (target < 0) {
3608		if (cap->mds_wanted | cap->issued)
 
3609			ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
3610		__ceph_remove_cap(cap, false);
3611		goto out_unlock;
3612	}
3613
3614	/*
3615	 * now we know we haven't received the cap import message yet
3616	 * because the exported cap still exist.
3617	 */
3618
3619	issued = cap->issued;
3620	if (issued != cap->implemented)
3621		pr_err_ratelimited("handle_cap_export: issued != implemented: "
3622				"ino (%llx.%llx) mds%d seq %d mseq %d "
3623				"issued %s implemented %s\n",
3624				ceph_vinop(inode), mds, cap->seq, cap->mseq,
3625				ceph_cap_string(issued),
3626				ceph_cap_string(cap->implemented));
3627
3628
3629	tcap = __get_cap_for_mds(ci, target);
3630	if (tcap) {
3631		/* already have caps from the target */
3632		if (tcap->cap_id == t_cap_id &&
3633		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
3634			dout(" updating import cap %p mds%d\n", tcap, target);
3635			tcap->cap_id = t_cap_id;
3636			tcap->seq = t_seq - 1;
3637			tcap->issue_seq = t_seq - 1;
 
3638			tcap->issued |= issued;
3639			tcap->implemented |= issued;
3640			if (cap == ci->i_auth_cap)
3641				ci->i_auth_cap = tcap;
3642
3643			if (!list_empty(&ci->i_cap_flush_list) &&
3644			    ci->i_auth_cap == tcap) {
3645				spin_lock(&mdsc->cap_dirty_lock);
3646				list_move_tail(&ci->i_flushing_item,
3647					       &tcap->session->s_cap_flushing);
3648				spin_unlock(&mdsc->cap_dirty_lock);
3649			}
3650		}
3651		__ceph_remove_cap(cap, false);
3652		goto out_unlock;
3653	} else if (tsession) {
3654		/* add placeholder for the export tagert */
3655		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
3656		tcap = new_cap;
3657		ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
3658			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
3659
3660		if (!list_empty(&ci->i_cap_flush_list) &&
3661		    ci->i_auth_cap == tcap) {
3662			spin_lock(&mdsc->cap_dirty_lock);
3663			list_move_tail(&ci->i_flushing_item,
3664				       &tcap->session->s_cap_flushing);
3665			spin_unlock(&mdsc->cap_dirty_lock);
3666		}
3667
3668		__ceph_remove_cap(cap, false);
3669		goto out_unlock;
3670	}
3671
3672	spin_unlock(&ci->i_ceph_lock);
3673	mutex_unlock(&session->s_mutex);
3674
3675	/* open target session */
3676	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
3677	if (!IS_ERR(tsession)) {
3678		if (mds > target) {
3679			mutex_lock(&session->s_mutex);
3680			mutex_lock_nested(&tsession->s_mutex,
3681					  SINGLE_DEPTH_NESTING);
3682		} else {
3683			mutex_lock(&tsession->s_mutex);
3684			mutex_lock_nested(&session->s_mutex,
3685					  SINGLE_DEPTH_NESTING);
3686		}
3687		new_cap = ceph_get_cap(mdsc, NULL);
3688	} else {
3689		WARN_ON(1);
3690		tsession = NULL;
3691		target = -1;
3692	}
3693	goto retry;
3694
3695out_unlock:
3696	spin_unlock(&ci->i_ceph_lock);
3697	mutex_unlock(&session->s_mutex);
3698	if (tsession) {
3699		mutex_unlock(&tsession->s_mutex);
3700		ceph_put_mds_session(tsession);
3701	}
3702	if (new_cap)
3703		ceph_put_cap(mdsc, new_cap);
3704}
3705
3706/*
3707 * Handle cap IMPORT.
3708 *
3709 * caller holds s_mutex. acquires i_ceph_lock
3710 */
3711static void handle_cap_import(struct ceph_mds_client *mdsc,
3712			      struct inode *inode, struct ceph_mds_caps *im,
3713			      struct ceph_mds_cap_peer *ph,
3714			      struct ceph_mds_session *session,
3715			      struct ceph_cap **target_cap, int *old_issued)
3716	__acquires(ci->i_ceph_lock)
3717{
3718	struct ceph_inode_info *ci = ceph_inode(inode);
3719	struct ceph_cap *cap, *ocap, *new_cap = NULL;
3720	int mds = session->s_mds;
3721	int issued;
3722	unsigned caps = le32_to_cpu(im->caps);
3723	unsigned wanted = le32_to_cpu(im->wanted);
3724	unsigned seq = le32_to_cpu(im->seq);
3725	unsigned mseq = le32_to_cpu(im->migrate_seq);
3726	u64 realmino = le64_to_cpu(im->realm);
3727	u64 cap_id = le64_to_cpu(im->cap_id);
3728	u64 p_cap_id;
3729	int peer;
3730
3731	if (ph) {
3732		p_cap_id = le64_to_cpu(ph->cap_id);
3733		peer = le32_to_cpu(ph->mds);
3734	} else {
3735		p_cap_id = 0;
3736		peer = -1;
3737	}
3738
3739	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
3740	     inode, ci, mds, mseq, peer);
3741
3742retry:
3743	spin_lock(&ci->i_ceph_lock);
3744	cap = __get_cap_for_mds(ci, mds);
3745	if (!cap) {
3746		if (!new_cap) {
3747			spin_unlock(&ci->i_ceph_lock);
3748			new_cap = ceph_get_cap(mdsc, NULL);
3749			goto retry;
3750		}
3751		cap = new_cap;
3752	} else {
3753		if (new_cap) {
3754			ceph_put_cap(mdsc, new_cap);
3755			new_cap = NULL;
3756		}
3757	}
3758
3759	__ceph_caps_issued(ci, &issued);
3760	issued |= __ceph_caps_dirty(ci);
3761
3762	ceph_add_cap(inode, session, cap_id, -1, caps, wanted, seq, mseq,
3763		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
3764
3765	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
3766	if (ocap && ocap->cap_id == p_cap_id) {
3767		dout(" remove export cap %p mds%d flags %d\n",
3768		     ocap, peer, ph->flags);
3769		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
3770		    (ocap->seq != le32_to_cpu(ph->seq) ||
3771		     ocap->mseq != le32_to_cpu(ph->mseq))) {
3772			pr_err_ratelimited("handle_cap_import: "
3773					"mismatched seq/mseq: ino (%llx.%llx) "
3774					"mds%d seq %d mseq %d importer mds%d "
3775					"has peer seq %d mseq %d\n",
3776					ceph_vinop(inode), peer, ocap->seq,
3777					ocap->mseq, mds, le32_to_cpu(ph->seq),
3778					le32_to_cpu(ph->mseq));
3779		}
3780		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
3781	}
3782
3783	/* make sure we re-request max_size, if necessary */
 
3784	ci->i_requested_max_size = 0;
3785
3786	*old_issued = issued;
3787	*target_cap = cap;
3788}
3789
3790/*
3791 * Handle a caps message from the MDS.
3792 *
3793 * Identify the appropriate session, inode, and call the right handler
3794 * based on the cap op.
3795 */
3796void ceph_handle_caps(struct ceph_mds_session *session,
3797		      struct ceph_msg *msg)
3798{
3799	struct ceph_mds_client *mdsc = session->s_mdsc;
 
3800	struct inode *inode;
3801	struct ceph_inode_info *ci;
3802	struct ceph_cap *cap;
3803	struct ceph_mds_caps *h;
3804	struct ceph_mds_cap_peer *peer = NULL;
3805	struct ceph_snap_realm *realm = NULL;
3806	int op;
3807	int msg_version = le16_to_cpu(msg->hdr.version);
 
3808	u32 seq, mseq;
3809	struct ceph_vino vino;
 
 
 
 
3810	void *snaptrace;
3811	size_t snaptrace_len;
3812	void *p, *end;
3813	struct cap_extra_info extra_info = {};
3814
3815	dout("handle_caps from mds%d\n", session->s_mds);
3816
3817	/* decode */
3818	end = msg->front.iov_base + msg->front.iov_len;
 
3819	if (msg->front.iov_len < sizeof(*h))
3820		goto bad;
3821	h = msg->front.iov_base;
3822	op = le32_to_cpu(h->op);
3823	vino.ino = le64_to_cpu(h->ino);
3824	vino.snap = CEPH_NOSNAP;
3825	seq = le32_to_cpu(h->seq);
3826	mseq = le32_to_cpu(h->migrate_seq);
3827
3828	snaptrace = h + 1;
3829	snaptrace_len = le32_to_cpu(h->snap_trace_len);
3830	p = snaptrace + snaptrace_len;
3831
3832	if (msg_version >= 2) {
3833		u32 flock_len;
3834		ceph_decode_32_safe(&p, end, flock_len, bad);
3835		if (p + flock_len > end)
3836			goto bad;
3837		p += flock_len;
3838	}
3839
3840	if (msg_version >= 3) {
3841		if (op == CEPH_CAP_OP_IMPORT) {
3842			if (p + sizeof(*peer) > end)
3843				goto bad;
3844			peer = p;
3845			p += sizeof(*peer);
3846		} else if (op == CEPH_CAP_OP_EXPORT) {
3847			/* recorded in unused fields */
3848			peer = (void *)&h->size;
3849		}
3850	}
3851
3852	if (msg_version >= 4) {
3853		ceph_decode_64_safe(&p, end, extra_info.inline_version, bad);
3854		ceph_decode_32_safe(&p, end, extra_info.inline_len, bad);
3855		if (p + extra_info.inline_len > end)
3856			goto bad;
3857		extra_info.inline_data = p;
3858		p += extra_info.inline_len;
3859	}
3860
3861	if (msg_version >= 5) {
3862		struct ceph_osd_client	*osdc = &mdsc->fsc->client->osdc;
3863		u32			epoch_barrier;
3864
3865		ceph_decode_32_safe(&p, end, epoch_barrier, bad);
3866		ceph_osdc_update_epoch_barrier(osdc, epoch_barrier);
3867	}
3868
3869	if (msg_version >= 8) {
3870		u64 flush_tid;
3871		u32 caller_uid, caller_gid;
 
3872		u32 pool_ns_len;
3873
 
3874		/* version >= 6 */
3875		ceph_decode_64_safe(&p, end, flush_tid, bad);
3876		/* version >= 7 */
3877		ceph_decode_32_safe(&p, end, caller_uid, bad);
3878		ceph_decode_32_safe(&p, end, caller_gid, bad);
3879		/* version >= 8 */
3880		ceph_decode_32_safe(&p, end, pool_ns_len, bad);
3881		if (pool_ns_len > 0) {
3882			ceph_decode_need(&p, end, pool_ns_len, bad);
3883			extra_info.pool_ns =
3884				ceph_find_or_create_string(p, pool_ns_len);
3885			p += pool_ns_len;
3886		}
3887	}
3888
3889	if (msg_version >= 9) {
3890		struct ceph_timespec *btime;
3891
3892		if (p + sizeof(*btime) > end)
3893			goto bad;
3894		btime = p;
3895		ceph_decode_timespec64(&extra_info.btime, btime);
3896		p += sizeof(*btime);
3897		ceph_decode_64_safe(&p, end, extra_info.change_attr, bad);
3898	}
3899
3900	if (msg_version >= 11) {
3901		u32 flags;
3902		/* version >= 10 */
3903		ceph_decode_32_safe(&p, end, flags, bad);
3904		/* version >= 11 */
3905		extra_info.dirstat_valid = true;
3906		ceph_decode_64_safe(&p, end, extra_info.nfiles, bad);
3907		ceph_decode_64_safe(&p, end, extra_info.nsubdirs, bad);
3908	}
3909
3910	/* lookup ino */
3911	inode = ceph_find_inode(mdsc->fsc->sb, vino);
3912	ci = ceph_inode(inode);
3913	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
3914	     vino.snap, inode);
3915
3916	mutex_lock(&session->s_mutex);
3917	session->s_seq++;
3918	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
3919	     (unsigned)seq);
3920
3921	if (!inode) {
3922		dout(" i don't have ino %llx\n", vino.ino);
3923
3924		if (op == CEPH_CAP_OP_IMPORT) {
3925			cap = ceph_get_cap(mdsc, NULL);
3926			cap->cap_ino = vino.ino;
3927			cap->queue_release = 1;
3928			cap->cap_id = le64_to_cpu(h->cap_id);
3929			cap->mseq = mseq;
3930			cap->seq = seq;
3931			cap->issue_seq = seq;
3932			spin_lock(&session->s_cap_lock);
3933			__ceph_queue_cap_release(session, cap);
 
 
3934			spin_unlock(&session->s_cap_lock);
3935		}
3936		goto done;
3937	}
3938
3939	/* these will work even if we don't have a cap yet */
3940	switch (op) {
3941	case CEPH_CAP_OP_FLUSHSNAP_ACK:
3942		handle_cap_flushsnap_ack(inode, le64_to_cpu(msg->hdr.tid),
3943					 h, session);
3944		goto done;
3945
3946	case CEPH_CAP_OP_EXPORT:
3947		handle_cap_export(inode, h, peer, session);
3948		goto done_unlocked;
3949
3950	case CEPH_CAP_OP_IMPORT:
3951		realm = NULL;
3952		if (snaptrace_len) {
3953			down_write(&mdsc->snap_rwsem);
3954			ceph_update_snap_trace(mdsc, snaptrace,
3955					       snaptrace + snaptrace_len,
3956					       false, &realm);
3957			downgrade_write(&mdsc->snap_rwsem);
3958		} else {
3959			down_read(&mdsc->snap_rwsem);
3960		}
3961		handle_cap_import(mdsc, inode, h, peer, session,
3962				  &cap, &extra_info.issued);
3963		handle_cap_grant(inode, session, cap,
3964				 h, msg->middle, &extra_info);
 
3965		if (realm)
3966			ceph_put_snap_realm(mdsc, realm);
3967		goto done_unlocked;
3968	}
3969
3970	/* the rest require a cap */
3971	spin_lock(&ci->i_ceph_lock);
3972	cap = __get_cap_for_mds(ceph_inode(inode), session->s_mds);
3973	if (!cap) {
3974		dout(" no cap on %p ino %llx.%llx from mds%d\n",
3975		     inode, ceph_ino(inode), ceph_snap(inode),
3976		     session->s_mds);
3977		spin_unlock(&ci->i_ceph_lock);
3978		goto flush_cap_releases;
3979	}
3980
3981	/* note that each of these drops i_ceph_lock for us */
3982	switch (op) {
3983	case CEPH_CAP_OP_REVOKE:
3984	case CEPH_CAP_OP_GRANT:
3985		__ceph_caps_issued(ci, &extra_info.issued);
3986		extra_info.issued |= __ceph_caps_dirty(ci);
3987		handle_cap_grant(inode, session, cap,
3988				 h, msg->middle, &extra_info);
 
3989		goto done_unlocked;
3990
3991	case CEPH_CAP_OP_FLUSH_ACK:
3992		handle_cap_flush_ack(inode, le64_to_cpu(msg->hdr.tid),
3993				     h, session, cap);
3994		break;
3995
3996	case CEPH_CAP_OP_TRUNC:
3997		handle_cap_trunc(inode, h, session);
3998		break;
3999
4000	default:
4001		spin_unlock(&ci->i_ceph_lock);
4002		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
4003		       ceph_cap_op_name(op));
4004	}
4005
4006done:
4007	mutex_unlock(&session->s_mutex);
4008done_unlocked:
4009	ceph_put_string(extra_info.pool_ns);
4010	/* avoid calling iput_final() in mds dispatch threads */
4011	ceph_async_iput(inode);
4012	return;
4013
4014flush_cap_releases:
4015	/*
4016	 * send any cap release message to try to move things
4017	 * along for the mds (who clearly thinks we still have this
4018	 * cap).
4019	 */
4020	ceph_flush_cap_releases(mdsc, session);
4021	goto done;
 
 
 
 
 
 
4022
4023bad:
4024	pr_err("ceph_handle_caps: corrupt message\n");
4025	ceph_msg_dump(msg);
4026	return;
4027}
4028
4029/*
4030 * Delayed work handler to process end of delayed cap release LRU list.
4031 */
4032void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
4033{
4034	struct inode *inode;
4035	struct ceph_inode_info *ci;
4036	int flags = CHECK_CAPS_NODELAY;
4037
4038	dout("check_delayed_caps\n");
4039	while (1) {
4040		spin_lock(&mdsc->cap_delay_lock);
4041		if (list_empty(&mdsc->cap_delay_list))
4042			break;
4043		ci = list_first_entry(&mdsc->cap_delay_list,
4044				      struct ceph_inode_info,
4045				      i_cap_delay_list);
4046		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
4047		    time_before(jiffies, ci->i_hold_caps_max))
4048			break;
4049		list_del_init(&ci->i_cap_delay_list);
4050
4051		inode = igrab(&ci->vfs_inode);
4052		spin_unlock(&mdsc->cap_delay_lock);
4053
4054		if (inode) {
4055			dout("check_delayed_caps on %p\n", inode);
4056			ceph_check_caps(ci, flags, NULL);
4057			/* avoid calling iput_final() in tick thread */
4058			ceph_async_iput(inode);
4059		}
4060	}
4061	spin_unlock(&mdsc->cap_delay_lock);
4062}
4063
4064/*
4065 * Flush all dirty caps to the mds
4066 */
4067void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
4068{
4069	struct ceph_inode_info *ci;
4070	struct inode *inode;
4071
4072	dout("flush_dirty_caps\n");
4073	spin_lock(&mdsc->cap_dirty_lock);
4074	while (!list_empty(&mdsc->cap_dirty)) {
4075		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
4076				      i_dirty_item);
4077		inode = &ci->vfs_inode;
4078		ihold(inode);
4079		dout("flush_dirty_caps %p\n", inode);
4080		spin_unlock(&mdsc->cap_dirty_lock);
4081		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
4082		iput(inode);
4083		spin_lock(&mdsc->cap_dirty_lock);
4084	}
4085	spin_unlock(&mdsc->cap_dirty_lock);
4086	dout("flush_dirty_caps done\n");
4087}
4088
4089void __ceph_get_fmode(struct ceph_inode_info *ci, int fmode)
4090{
4091	int i;
4092	int bits = (fmode << 1) | 1;
4093	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4094		if (bits & (1 << i))
4095			ci->i_nr_by_mode[i]++;
4096	}
4097}
4098
4099/*
4100 * Drop open file reference.  If we were the last open file,
4101 * we may need to release capabilities to the MDS (or schedule
4102 * their delayed release).
4103 */
4104void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
4105{
4106	int i, last = 0;
4107	int bits = (fmode << 1) | 1;
4108	spin_lock(&ci->i_ceph_lock);
4109	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4110		if (bits & (1 << i)) {
4111			BUG_ON(ci->i_nr_by_mode[i] == 0);
4112			if (--ci->i_nr_by_mode[i] == 0)
4113				last++;
4114		}
4115	}
4116	dout("put_fmode %p fmode %d {%d,%d,%d,%d}\n",
4117	     &ci->vfs_inode, fmode,
4118	     ci->i_nr_by_mode[0], ci->i_nr_by_mode[1],
4119	     ci->i_nr_by_mode[2], ci->i_nr_by_mode[3]);
4120	spin_unlock(&ci->i_ceph_lock);
4121
4122	if (last && ci->i_vino.snap == CEPH_NOSNAP)
4123		ceph_check_caps(ci, 0, NULL);
4124}
4125
4126/*
4127 * For a soon-to-be unlinked file, drop the LINK caps. If it
4128 * looks like the link count will hit 0, drop any other caps (other
4129 * than PIN) we don't specifically want (due to the file still being
4130 * open).
4131 */
4132int ceph_drop_caps_for_unlink(struct inode *inode)
4133{
4134	struct ceph_inode_info *ci = ceph_inode(inode);
4135	int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
4136
4137	spin_lock(&ci->i_ceph_lock);
4138	if (inode->i_nlink == 1) {
4139		drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
4140
4141		ci->i_ceph_flags |= CEPH_I_NODELAY;
4142		if (__ceph_caps_dirty(ci)) {
4143			struct ceph_mds_client *mdsc =
4144				ceph_inode_to_client(inode)->mdsc;
4145			__cap_delay_requeue_front(mdsc, ci);
4146		}
4147	}
4148	spin_unlock(&ci->i_ceph_lock);
4149	return drop;
4150}
4151
4152/*
4153 * Helpers for embedding cap and dentry lease releases into mds
4154 * requests.
4155 *
4156 * @force is used by dentry_release (below) to force inclusion of a
4157 * record for the directory inode, even when there aren't any caps to
4158 * drop.
4159 */
4160int ceph_encode_inode_release(void **p, struct inode *inode,
4161			      int mds, int drop, int unless, int force)
4162{
4163	struct ceph_inode_info *ci = ceph_inode(inode);
4164	struct ceph_cap *cap;
4165	struct ceph_mds_request_release *rel = *p;
4166	int used, dirty;
4167	int ret = 0;
4168
4169	spin_lock(&ci->i_ceph_lock);
4170	used = __ceph_caps_used(ci);
4171	dirty = __ceph_caps_dirty(ci);
4172
4173	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
4174	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
4175	     ceph_cap_string(unless));
4176
4177	/* only drop unused, clean caps */
4178	drop &= ~(used | dirty);
4179
4180	cap = __get_cap_for_mds(ci, mds);
4181	if (cap && __cap_is_valid(cap)) {
4182		unless &= cap->issued;
4183		if (unless) {
4184			if (unless & CEPH_CAP_AUTH_EXCL)
4185				drop &= ~CEPH_CAP_AUTH_SHARED;
4186			if (unless & CEPH_CAP_LINK_EXCL)
4187				drop &= ~CEPH_CAP_LINK_SHARED;
4188			if (unless & CEPH_CAP_XATTR_EXCL)
4189				drop &= ~CEPH_CAP_XATTR_SHARED;
4190			if (unless & CEPH_CAP_FILE_EXCL)
4191				drop &= ~CEPH_CAP_FILE_SHARED;
4192		}
4193
4194		if (force || (cap->issued & drop)) {
4195			if (cap->issued & drop) {
4196				int wanted = __ceph_caps_wanted(ci);
4197				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
4198					wanted |= cap->mds_wanted;
4199				dout("encode_inode_release %p cap %p "
4200				     "%s -> %s, wanted %s -> %s\n", inode, cap,
4201				     ceph_cap_string(cap->issued),
4202				     ceph_cap_string(cap->issued & ~drop),
4203				     ceph_cap_string(cap->mds_wanted),
4204				     ceph_cap_string(wanted));
4205
4206				cap->issued &= ~drop;
4207				cap->implemented &= ~drop;
4208				cap->mds_wanted = wanted;
4209			} else {
4210				dout("encode_inode_release %p cap %p %s"
4211				     " (force)\n", inode, cap,
4212				     ceph_cap_string(cap->issued));
4213			}
4214
4215			rel->ino = cpu_to_le64(ceph_ino(inode));
4216			rel->cap_id = cpu_to_le64(cap->cap_id);
4217			rel->seq = cpu_to_le32(cap->seq);
4218			rel->issue_seq = cpu_to_le32(cap->issue_seq);
4219			rel->mseq = cpu_to_le32(cap->mseq);
4220			rel->caps = cpu_to_le32(cap->implemented);
4221			rel->wanted = cpu_to_le32(cap->mds_wanted);
4222			rel->dname_len = 0;
4223			rel->dname_seq = 0;
4224			*p += sizeof(*rel);
4225			ret = 1;
4226		} else {
4227			dout("encode_inode_release %p cap %p %s (noop)\n",
4228			     inode, cap, ceph_cap_string(cap->issued));
4229		}
4230	}
4231	spin_unlock(&ci->i_ceph_lock);
4232	return ret;
4233}
4234
4235int ceph_encode_dentry_release(void **p, struct dentry *dentry,
4236			       struct inode *dir,
4237			       int mds, int drop, int unless)
4238{
4239	struct dentry *parent = NULL;
4240	struct ceph_mds_request_release *rel = *p;
4241	struct ceph_dentry_info *di = ceph_dentry(dentry);
4242	int force = 0;
4243	int ret;
4244
4245	/*
4246	 * force an record for the directory caps if we have a dentry lease.
4247	 * this is racy (can't take i_ceph_lock and d_lock together), but it
4248	 * doesn't have to be perfect; the mds will revoke anything we don't
4249	 * release.
4250	 */
4251	spin_lock(&dentry->d_lock);
4252	if (di->lease_session && di->lease_session->s_mds == mds)
4253		force = 1;
4254	if (!dir) {
4255		parent = dget(dentry->d_parent);
4256		dir = d_inode(parent);
4257	}
4258	spin_unlock(&dentry->d_lock);
4259
4260	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
4261	dput(parent);
4262
4263	spin_lock(&dentry->d_lock);
4264	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
4265		dout("encode_dentry_release %p mds%d seq %d\n",
4266		     dentry, mds, (int)di->lease_seq);
4267		rel->dname_len = cpu_to_le32(dentry->d_name.len);
4268		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
4269		*p += dentry->d_name.len;
4270		rel->dname_seq = cpu_to_le32(di->lease_seq);
4271		__ceph_mdsc_drop_dentry_lease(dentry);
4272	}
4273	spin_unlock(&dentry->d_lock);
4274	return ret;
4275}