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