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v3.15
 
   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
 224static struct ceph_cap *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 */
 511int 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_reservation *caps_reservation)
 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 *new_cap = NULL;
 520	struct ceph_cap *cap;
 521	int mds = session->s_mds;
 522	int actual_wanted;
 
 
 
 523
 524	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 525	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 526
 527	/*
 528	 * If we are opening the file, include file mode wanted bits
 529	 * in wanted.
 530	 */
 531	if (fmode >= 0)
 532		wanted |= ceph_caps_for_mode(fmode);
 533
 534retry:
 535	spin_lock(&ci->i_ceph_lock);
 536	cap = __get_cap_for_mds(ci, mds);
 537	if (!cap) {
 538		if (new_cap) {
 539			cap = new_cap;
 540			new_cap = NULL;
 541		} else {
 542			spin_unlock(&ci->i_ceph_lock);
 543			new_cap = get_cap(mdsc, caps_reservation);
 544			if (new_cap == NULL)
 545				return -ENOMEM;
 546			goto retry;
 547		}
 548
 549		cap->issued = 0;
 550		cap->implemented = 0;
 551		cap->mds = mds;
 552		cap->mds_wanted = 0;
 553		cap->mseq = 0;
 554
 555		cap->ci = ci;
 556		__insert_cap_node(ci, cap);
 557
 558		/* add to session cap list */
 559		cap->session = session;
 560		spin_lock(&session->s_cap_lock);
 561		list_add_tail(&cap->session_caps, &session->s_caps);
 562		session->s_nr_caps++;
 
 563		spin_unlock(&session->s_cap_lock);
 564	} else {
 565		if (new_cap)
 566			ceph_put_cap(mdsc, new_cap);
 
 
 
 
 567
 568		/*
 569		 * auth mds of the inode changed. we received the cap export
 570		 * message, but still haven't received the cap import message.
 571		 * handle_cap_export() updated the new auth MDS' cap.
 572		 *
 573		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 574		 * a message that was send before the cap import message. So
 575		 * don't remove caps.
 576		 */
 577		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 578			WARN_ON(cap != ci->i_auth_cap);
 579			WARN_ON(cap->cap_id != cap_id);
 580			seq = cap->seq;
 581			mseq = cap->mseq;
 582			issued |= cap->issued;
 583			flags |= CEPH_CAP_FLAG_AUTH;
 584		}
 585	}
 586
 587	if (!ci->i_snap_realm) {
 
 
 588		/*
 589		 * add this inode to the appropriate snap realm
 590		 */
 591		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 592							       realmino);
 593		if (realm) {
 594			ceph_get_snap_realm(mdsc, realm);
 595			spin_lock(&realm->inodes_with_caps_lock);
 596			ci->i_snap_realm = realm;
 597			list_add(&ci->i_snap_realm_item,
 598				 &realm->inodes_with_caps);
 599			spin_unlock(&realm->inodes_with_caps_lock);
 600		} else {
 601			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 602			       realmino);
 603			WARN_ON(!realm);
 604		}
 605	}
 606
 607	__check_cap_issue(ci, cap, issued);
 608
 609	/*
 610	 * If we are issued caps we don't want, or the mds' wanted
 611	 * value appears to be off, queue a check so we'll release
 612	 * later and/or update the mds wanted value.
 613	 */
 614	actual_wanted = __ceph_caps_wanted(ci);
 615	if ((wanted & ~actual_wanted) ||
 616	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 617		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 618		     ceph_cap_string(issued), ceph_cap_string(wanted),
 619		     ceph_cap_string(actual_wanted));
 620		__cap_delay_requeue(mdsc, ci);
 621	}
 622
 623	if (flags & CEPH_CAP_FLAG_AUTH) {
 624		if (ci->i_auth_cap == NULL ||
 625		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 
 
 
 626			ci->i_auth_cap = cap;
 627			cap->mds_wanted = wanted;
 628		}
 629		ci->i_cap_exporting_issued = 0;
 630	} else {
 631		WARN_ON(ci->i_auth_cap == cap);
 632	}
 633
 634	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 635	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 636	     ceph_cap_string(issued|cap->issued), seq, mds);
 637	cap->cap_id = cap_id;
 638	cap->issued = issued;
 639	cap->implemented |= issued;
 640	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 641		cap->mds_wanted = wanted;
 642	else
 643		cap->mds_wanted |= wanted;
 644	cap->seq = seq;
 645	cap->issue_seq = seq;
 646	cap->mseq = mseq;
 647	cap->cap_gen = session->s_cap_gen;
 648
 649	if (fmode >= 0)
 650		__ceph_get_fmode(ci, fmode);
 651	spin_unlock(&ci->i_ceph_lock);
 652	wake_up_all(&ci->i_cap_wq);
 653	return 0;
 654}
 655
 656/*
 657 * Return true if cap has not timed out and belongs to the current
 658 * generation of the MDS session (i.e. has not gone 'stale' due to
 659 * us losing touch with the mds).
 660 */
 661static int __cap_is_valid(struct ceph_cap *cap)
 662{
 663	unsigned long ttl;
 664	u32 gen;
 665
 666	spin_lock(&cap->session->s_gen_ttl_lock);
 667	gen = cap->session->s_cap_gen;
 668	ttl = cap->session->s_cap_ttl;
 669	spin_unlock(&cap->session->s_gen_ttl_lock);
 670
 671	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 672		dout("__cap_is_valid %p cap %p issued %s "
 673		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 674		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 675		return 0;
 676	}
 677
 678	return 1;
 679}
 680
 681/*
 682 * Return set of valid cap bits issued to us.  Note that caps time
 683 * out, and may be invalidated in bulk if the client session times out
 684 * and session->s_cap_gen is bumped.
 685 */
 686int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 687{
 688	int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
 689	struct ceph_cap *cap;
 690	struct rb_node *p;
 691
 692	if (implemented)
 693		*implemented = 0;
 694	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 695		cap = rb_entry(p, struct ceph_cap, ci_node);
 696		if (!__cap_is_valid(cap))
 697			continue;
 698		dout("__ceph_caps_issued %p cap %p issued %s\n",
 699		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 700		have |= cap->issued;
 701		if (implemented)
 702			*implemented |= cap->implemented;
 703	}
 704	/*
 705	 * exclude caps issued by non-auth MDS, but are been revoking
 706	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 707	 * these caps, but the message is delayed.
 708	 */
 709	if (ci->i_auth_cap) {
 710		cap = ci->i_auth_cap;
 711		have &= ~cap->implemented | cap->issued;
 712	}
 713	return have;
 714}
 715
 716/*
 717 * Get cap bits issued by caps other than @ocap
 718 */
 719int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 720{
 721	int have = ci->i_snap_caps;
 722	struct ceph_cap *cap;
 723	struct rb_node *p;
 724
 725	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 726		cap = rb_entry(p, struct ceph_cap, ci_node);
 727		if (cap == ocap)
 728			continue;
 729		if (!__cap_is_valid(cap))
 730			continue;
 731		have |= cap->issued;
 732	}
 733	return have;
 734}
 735
 736/*
 737 * Move a cap to the end of the LRU (oldest caps at list head, newest
 738 * at list tail).
 739 */
 740static void __touch_cap(struct ceph_cap *cap)
 741{
 742	struct ceph_mds_session *s = cap->session;
 743
 744	spin_lock(&s->s_cap_lock);
 745	if (s->s_cap_iterator == NULL) {
 746		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 747		     s->s_mds);
 748		list_move_tail(&cap->session_caps, &s->s_caps);
 749	} else {
 750		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 751		     &cap->ci->vfs_inode, cap, s->s_mds);
 752	}
 753	spin_unlock(&s->s_cap_lock);
 754}
 755
 756/*
 757 * Check if we hold the given mask.  If so, move the cap(s) to the
 758 * front of their respective LRUs.  (This is the preferred way for
 759 * callers to check for caps they want.)
 760 */
 761int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 762{
 763	struct ceph_cap *cap;
 764	struct rb_node *p;
 765	int have = ci->i_snap_caps;
 766
 767	if ((have & mask) == mask) {
 768		dout("__ceph_caps_issued_mask %p snap issued %s"
 769		     " (mask %s)\n", &ci->vfs_inode,
 770		     ceph_cap_string(have),
 771		     ceph_cap_string(mask));
 772		return 1;
 773	}
 774
 775	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 776		cap = rb_entry(p, struct ceph_cap, ci_node);
 777		if (!__cap_is_valid(cap))
 778			continue;
 779		if ((cap->issued & mask) == mask) {
 780			dout("__ceph_caps_issued_mask %p cap %p issued %s"
 781			     " (mask %s)\n", &ci->vfs_inode, cap,
 782			     ceph_cap_string(cap->issued),
 783			     ceph_cap_string(mask));
 784			if (touch)
 785				__touch_cap(cap);
 786			return 1;
 787		}
 788
 789		/* does a combination of caps satisfy mask? */
 790		have |= cap->issued;
 791		if ((have & mask) == mask) {
 792			dout("__ceph_caps_issued_mask %p combo issued %s"
 793			     " (mask %s)\n", &ci->vfs_inode,
 794			     ceph_cap_string(cap->issued),
 795			     ceph_cap_string(mask));
 796			if (touch) {
 797				struct rb_node *q;
 798
 799				/* touch this + preceding caps */
 800				__touch_cap(cap);
 801				for (q = rb_first(&ci->i_caps); q != p;
 802				     q = rb_next(q)) {
 803					cap = rb_entry(q, struct ceph_cap,
 804						       ci_node);
 805					if (!__cap_is_valid(cap))
 806						continue;
 807					__touch_cap(cap);
 
 808				}
 809			}
 810			return 1;
 811		}
 812	}
 813
 814	return 0;
 815}
 816
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 817/*
 818 * Return true if mask caps are currently being revoked by an MDS.
 819 */
 820int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 821			       struct ceph_cap *ocap, int mask)
 822{
 823	struct ceph_cap *cap;
 824	struct rb_node *p;
 825
 826	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 827		cap = rb_entry(p, struct ceph_cap, ci_node);
 828		if (cap != ocap &&
 829		    (cap->implemented & ~cap->issued & mask))
 830			return 1;
 831	}
 832	return 0;
 833}
 834
 835int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 836{
 837	struct inode *inode = &ci->vfs_inode;
 838	int ret;
 839
 840	spin_lock(&ci->i_ceph_lock);
 841	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 842	spin_unlock(&ci->i_ceph_lock);
 843	dout("ceph_caps_revoking %p %s = %d\n", inode,
 844	     ceph_cap_string(mask), ret);
 845	return ret;
 846}
 847
 848int __ceph_caps_used(struct ceph_inode_info *ci)
 849{
 850	int used = 0;
 851	if (ci->i_pin_ref)
 852		used |= CEPH_CAP_PIN;
 853	if (ci->i_rd_ref)
 854		used |= CEPH_CAP_FILE_RD;
 855	if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
 
 
 856		used |= CEPH_CAP_FILE_CACHE;
 857	if (ci->i_wr_ref)
 858		used |= CEPH_CAP_FILE_WR;
 859	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 860		used |= CEPH_CAP_FILE_BUFFER;
 
 
 861	return used;
 862}
 863
 
 
 864/*
 865 * wanted, by virtue of open file modes
 866 */
 867int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 868{
 869	int want = 0;
 870	int mode;
 871	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
 872		if (ci->i_nr_by_mode[mode])
 873			want |= ceph_caps_for_mode(mode);
 874	return want;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 875}
 876
 877/*
 878 * Return caps we have registered with the MDS(s) as 'wanted'.
 879 */
 880int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
 881{
 882	struct ceph_cap *cap;
 883	struct rb_node *p;
 884	int mds_wanted = 0;
 885
 886	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 887		cap = rb_entry(p, struct ceph_cap, ci_node);
 888		if (!__cap_is_valid(cap))
 889			continue;
 890		if (cap == ci->i_auth_cap)
 891			mds_wanted |= cap->mds_wanted;
 892		else
 893			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
 894	}
 895	return mds_wanted;
 896}
 897
 898/*
 899 * called under i_ceph_lock
 900 */
 901static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 902{
 903	return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_issued;
 904}
 905
 906int ceph_is_any_caps(struct inode *inode)
 907{
 908	struct ceph_inode_info *ci = ceph_inode(inode);
 909	int ret;
 910
 911	spin_lock(&ci->i_ceph_lock);
 912	ret = __ceph_is_any_caps(ci);
 913	spin_unlock(&ci->i_ceph_lock);
 914
 915	return ret;
 916}
 917
 918/*
 919 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
 920 *
 921 * caller should hold i_ceph_lock.
 922 * caller will not hold session s_mutex if called from destroy_inode.
 923 */
 924void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
 925{
 926	struct ceph_mds_session *session = cap->session;
 927	struct ceph_inode_info *ci = cap->ci;
 928	struct ceph_mds_client *mdsc =
 929		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
 930	int removed = 0;
 931
 932	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 933
 934	/* remove from session list */
 935	spin_lock(&session->s_cap_lock);
 936	/*
 937	 * s_cap_reconnect is protected by s_cap_lock. no one changes
 938	 * s_cap_gen while session is in the reconnect state.
 939	 */
 940	if (queue_release &&
 941	    (!session->s_cap_reconnect ||
 942	     cap->cap_gen == session->s_cap_gen))
 943		__queue_cap_release(session, ci->i_vino.ino, cap->cap_id,
 944				    cap->mseq, cap->issue_seq);
 945
 946	if (session->s_cap_iterator == cap) {
 947		/* not yet, we are iterating over this very cap */
 948		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
 949		     cap, cap->session);
 950	} else {
 951		list_del_init(&cap->session_caps);
 952		session->s_nr_caps--;
 
 953		cap->session = NULL;
 954		removed = 1;
 955	}
 956	/* protect backpointer with s_cap_lock: see iterate_session_caps */
 957	cap->ci = NULL;
 958	spin_unlock(&session->s_cap_lock);
 959
 960	/* remove from inode list */
 961	rb_erase(&cap->ci_node, &ci->i_caps);
 962	if (ci->i_auth_cap == cap)
 963		ci->i_auth_cap = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 964
 965	if (removed)
 966		ceph_put_cap(mdsc, cap);
 967
 968	if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
 969		struct ceph_snap_realm *realm = ci->i_snap_realm;
 970		spin_lock(&realm->inodes_with_caps_lock);
 971		list_del_init(&ci->i_snap_realm_item);
 972		ci->i_snap_realm_counter++;
 973		ci->i_snap_realm = NULL;
 974		spin_unlock(&realm->inodes_with_caps_lock);
 975		ceph_put_snap_realm(mdsc, realm);
 976	}
 977	if (!__ceph_is_any_real_caps(ci))
 978		__cap_delay_cancel(mdsc, ci);
 
 979}
 980
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 981/*
 982 * Build and send a cap message to the given MDS.
 983 *
 984 * Caller should be holding s_mutex.
 985 */
 986static int send_cap_msg(struct ceph_mds_session *session,
 987			u64 ino, u64 cid, int op,
 988			int caps, int wanted, int dirty,
 989			u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
 990			u64 size, u64 max_size,
 991			struct timespec *mtime, struct timespec *atime,
 992			u64 time_warp_seq,
 993			kuid_t uid, kgid_t gid, umode_t mode,
 994			u64 xattr_version,
 995			struct ceph_buffer *xattrs_buf,
 996			u64 follows)
 997{
 998	struct ceph_mds_caps *fc;
 999	struct ceph_msg *msg;
 
1000
1001	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
1002	     " seq %u/%u mseq %u follows %lld size %llu/%llu"
1003	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
1004	     cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
1005	     ceph_cap_string(dirty),
1006	     seq, issue_seq, mseq, follows, size, max_size,
1007	     xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);
1008
1009	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc), GFP_NOFS, false);
1010	if (!msg)
1011		return -ENOMEM;
1012
1013	msg->hdr.tid = cpu_to_le64(flush_tid);
1014
1015	fc = msg->front.iov_base;
1016	memset(fc, 0, sizeof(*fc));
1017
1018	fc->cap_id = cpu_to_le64(cid);
1019	fc->op = cpu_to_le32(op);
1020	fc->seq = cpu_to_le32(seq);
1021	fc->issue_seq = cpu_to_le32(issue_seq);
1022	fc->migrate_seq = cpu_to_le32(mseq);
1023	fc->caps = cpu_to_le32(caps);
1024	fc->wanted = cpu_to_le32(wanted);
1025	fc->dirty = cpu_to_le32(dirty);
1026	fc->ino = cpu_to_le64(ino);
1027	fc->snap_follows = cpu_to_le64(follows);
1028
1029	fc->size = cpu_to_le64(size);
1030	fc->max_size = cpu_to_le64(max_size);
1031	if (mtime)
1032		ceph_encode_timespec(&fc->mtime, mtime);
1033	if (atime)
1034		ceph_encode_timespec(&fc->atime, atime);
1035	fc->time_warp_seq = cpu_to_le32(time_warp_seq);
1036
1037	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, uid));
1038	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, gid));
1039	fc->mode = cpu_to_le32(mode);
1040
1041	fc->xattr_version = cpu_to_le64(xattr_version);
1042	if (xattrs_buf) {
1043		msg->middle = ceph_buffer_get(xattrs_buf);
1044		fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
1045		msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
1046	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1047
1048	ceph_con_send(&session->s_con, msg);
1049	return 0;
1050}
 
 
 
 
 
 
1051
1052void __queue_cap_release(struct ceph_mds_session *session,
1053			 u64 ino, u64 cap_id, u32 migrate_seq,
1054			 u32 issue_seq)
1055{
1056	struct ceph_msg *msg;
1057	struct ceph_mds_cap_release *head;
1058	struct ceph_mds_cap_item *item;
1059
1060	BUG_ON(!session->s_num_cap_releases);
1061	msg = list_first_entry(&session->s_cap_releases,
1062			       struct ceph_msg, list_head);
1063
1064	dout(" adding %llx release to mds%d msg %p (%d left)\n",
1065	     ino, session->s_mds, msg, session->s_num_cap_releases);
1066
1067	BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
1068	head = msg->front.iov_base;
1069	le32_add_cpu(&head->num, 1);
1070	item = msg->front.iov_base + msg->front.iov_len;
1071	item->ino = cpu_to_le64(ino);
1072	item->cap_id = cpu_to_le64(cap_id);
1073	item->migrate_seq = cpu_to_le32(migrate_seq);
1074	item->seq = cpu_to_le32(issue_seq);
1075
1076	session->s_num_cap_releases--;
1077
1078	msg->front.iov_len += sizeof(*item);
1079	if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
1080		dout(" release msg %p full\n", msg);
1081		list_move_tail(&msg->list_head, &session->s_cap_releases_done);
1082	} else {
1083		dout(" release msg %p at %d/%d (%d)\n", msg,
1084		     (int)le32_to_cpu(head->num),
1085		     (int)CEPH_CAPS_PER_RELEASE,
1086		     (int)msg->front.iov_len);
1087	}
1088}
1089
1090/*
1091 * Queue cap releases when an inode is dropped from our cache.  Since
1092 * inode is about to be destroyed, there is no need for i_ceph_lock.
1093 */
1094void ceph_queue_caps_release(struct inode *inode)
1095{
1096	struct ceph_inode_info *ci = ceph_inode(inode);
1097	struct rb_node *p;
1098
 
 
 
1099	p = rb_first(&ci->i_caps);
1100	while (p) {
1101		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1102		p = rb_next(p);
1103		__ceph_remove_cap(cap, true);
1104	}
 
1105}
1106
1107/*
1108 * Send a cap msg on the given inode.  Update our caps state, then
1109 * drop i_ceph_lock and send the message.
 
1110 *
1111 * Make note of max_size reported/requested from mds, revoked caps
1112 * that have now been implemented.
1113 *
1114 * Make half-hearted attempt ot to invalidate page cache if we are
1115 * dropping RDCACHE.  Note that this will leave behind locked pages
1116 * that we'll then need to deal with elsewhere.
1117 *
1118 * Return non-zero if delayed release, or we experienced an error
1119 * such that the caller should requeue + retry later.
1120 *
1121 * called with i_ceph_lock, then drops it.
1122 * caller should hold snap_rwsem (read), s_mutex.
1123 */
1124static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1125		      int op, int used, int want, int retain, int flushing,
1126		      unsigned *pflush_tid)
1127	__releases(cap->ci->i_ceph_lock)
1128{
1129	struct ceph_inode_info *ci = cap->ci;
1130	struct inode *inode = &ci->vfs_inode;
1131	u64 cap_id = cap->cap_id;
1132	int held, revoking, dropping, keep;
1133	u64 seq, issue_seq, mseq, time_warp_seq, follows;
1134	u64 size, max_size;
1135	struct timespec mtime, atime;
1136	int wake = 0;
1137	umode_t mode;
1138	kuid_t uid;
1139	kgid_t gid;
1140	struct ceph_mds_session *session;
1141	u64 xattr_version = 0;
1142	struct ceph_buffer *xattr_blob = NULL;
1143	int delayed = 0;
1144	u64 flush_tid = 0;
1145	int i;
1146	int ret;
1147
1148	held = cap->issued | cap->implemented;
1149	revoking = cap->implemented & ~cap->issued;
1150	retain &= ~revoking;
1151	dropping = cap->issued & ~retain;
1152
1153	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1154	     inode, cap, cap->session,
1155	     ceph_cap_string(held), ceph_cap_string(held & retain),
1156	     ceph_cap_string(revoking));
1157	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1158
1159	session = cap->session;
1160
1161	/* don't release wanted unless we've waited a bit. */
1162	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1163	    time_before(jiffies, ci->i_hold_caps_min)) {
1164		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1165		     ceph_cap_string(cap->issued),
1166		     ceph_cap_string(cap->issued & retain),
1167		     ceph_cap_string(cap->mds_wanted),
1168		     ceph_cap_string(want));
1169		want |= cap->mds_wanted;
1170		retain |= cap->issued;
1171		delayed = 1;
1172	}
1173	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1174
1175	cap->issued &= retain;  /* drop bits we don't want */
1176	if (cap->implemented & ~cap->issued) {
1177		/*
1178		 * Wake up any waiters on wanted -> needed transition.
1179		 * This is due to the weird transition from buffered
1180		 * to sync IO... we need to flush dirty pages _before_
1181		 * allowing sync writes to avoid reordering.
1182		 */
1183		wake = 1;
1184	}
1185	cap->implemented &= cap->issued | used;
1186	cap->mds_wanted = want;
1187
1188	if (flushing) {
1189		/*
1190		 * assign a tid for flush operations so we can avoid
1191		 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
1192		 * clean type races.  track latest tid for every bit
1193		 * so we can handle flush AxFw, flush Fw, and have the
1194		 * first ack clean Ax.
1195		 */
1196		flush_tid = ++ci->i_cap_flush_last_tid;
1197		if (pflush_tid)
1198			*pflush_tid = flush_tid;
1199		dout(" cap_flush_tid %d\n", (int)flush_tid);
1200		for (i = 0; i < CEPH_CAP_BITS; i++)
1201			if (flushing & (1 << i))
1202				ci->i_cap_flush_tid[i] = flush_tid;
 
1203
1204		follows = ci->i_head_snapc->seq;
 
 
 
1205	} else {
1206		follows = 0;
 
1207	}
1208
1209	keep = cap->implemented;
1210	seq = cap->seq;
1211	issue_seq = cap->issue_seq;
1212	mseq = cap->mseq;
1213	size = inode->i_size;
1214	ci->i_reported_size = size;
1215	max_size = ci->i_wanted_max_size;
1216	ci->i_requested_max_size = max_size;
1217	mtime = inode->i_mtime;
1218	atime = inode->i_atime;
1219	time_warp_seq = ci->i_time_warp_seq;
1220	uid = inode->i_uid;
1221	gid = inode->i_gid;
1222	mode = inode->i_mode;
1223
1224	if (flushing & CEPH_CAP_XATTR_EXCL) {
1225		__ceph_build_xattrs_blob(ci);
1226		xattr_blob = ci->i_xattrs.blob;
1227		xattr_version = ci->i_xattrs.version;
 
 
 
 
 
 
 
 
 
 
 
 
 
1228	}
 
 
1229
1230	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
1231
1232	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
1233		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
1234		size, max_size, &mtime, &atime, time_warp_seq,
1235		uid, gid, mode, xattr_version, xattr_blob,
1236		follows);
1237	if (ret < 0) {
1238		dout("error sending cap msg, must requeue %p\n", inode);
1239		delayed = 1;
 
1240	}
1241
1242	if (wake)
 
 
 
1243		wake_up_all(&ci->i_cap_wq);
 
 
 
 
 
 
 
 
 
1244
1245	return delayed;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1246}
1247
1248/*
1249 * When a snapshot is taken, clients accumulate dirty metadata on
1250 * inodes with capabilities in ceph_cap_snaps to describe the file
1251 * state at the time the snapshot was taken.  This must be flushed
1252 * asynchronously back to the MDS once sync writes complete and dirty
1253 * data is written out.
1254 *
1255 * Unless @again is true, skip cap_snaps that were already sent to
1256 * the MDS (i.e., during this session).
1257 *
1258 * Called under i_ceph_lock.  Takes s_mutex as needed.
1259 */
1260void __ceph_flush_snaps(struct ceph_inode_info *ci,
1261			struct ceph_mds_session **psession,
1262			int again)
1263		__releases(ci->i_ceph_lock)
1264		__acquires(ci->i_ceph_lock)
1265{
1266	struct inode *inode = &ci->vfs_inode;
1267	int mds;
1268	struct ceph_cap_snap *capsnap;
1269	u32 mseq;
1270	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1271	struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
1272						    session->s_mutex */
1273	u64 next_follows = 0;  /* keep track of how far we've gotten through the
1274			     i_cap_snaps list, and skip these entries next time
1275			     around to avoid an infinite loop */
1276
1277	if (psession)
1278		session = *psession;
1279
1280	dout("__flush_snaps %p\n", inode);
1281retry:
1282	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1283		/* avoid an infiniute loop after retry */
1284		if (capsnap->follows < next_follows)
1285			continue;
1286		/*
1287		 * we need to wait for sync writes to complete and for dirty
1288		 * pages to be written out.
1289		 */
1290		if (capsnap->dirty_pages || capsnap->writing)
1291			break;
1292
1293		/*
1294		 * if cap writeback already occurred, we should have dropped
1295		 * the capsnap in ceph_put_wrbuffer_cap_refs.
1296		 */
1297		BUG_ON(capsnap->dirty == 0);
1298
1299		/* pick mds, take s_mutex */
1300		if (ci->i_auth_cap == NULL) {
1301			dout("no auth cap (migrating?), doing nothing\n");
1302			goto out;
1303		}
1304
1305		/* only flush each capsnap once */
1306		if (!again && !list_empty(&capsnap->flushing_item)) {
1307			dout("already flushed %p, skipping\n", capsnap);
1308			continue;
1309		}
1310
1311		mds = ci->i_auth_cap->session->s_mds;
1312		mseq = ci->i_auth_cap->mseq;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1313
1314		if (session && session->s_mds != mds) {
1315			dout("oops, wrong session %p mutex\n", session);
1316			mutex_unlock(&session->s_mutex);
1317			ceph_put_mds_session(session);
1318			session = NULL;
1319		}
1320		if (!session) {
1321			spin_unlock(&ci->i_ceph_lock);
1322			mutex_lock(&mdsc->mutex);
1323			session = __ceph_lookup_mds_session(mdsc, mds);
1324			mutex_unlock(&mdsc->mutex);
1325			if (session) {
1326				dout("inverting session/ino locks on %p\n",
1327				     session);
1328				mutex_lock(&session->s_mutex);
1329			}
1330			/*
1331			 * if session == NULL, we raced against a cap
1332			 * deletion or migration.  retry, and we'll
1333			 * get a better @mds value next time.
1334			 */
1335			spin_lock(&ci->i_ceph_lock);
1336			goto retry;
1337		}
 
 
1338
1339		capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
1340		atomic_inc(&capsnap->nref);
1341		if (!list_empty(&capsnap->flushing_item))
1342			list_del_init(&capsnap->flushing_item);
1343		list_add_tail(&capsnap->flushing_item,
1344			      &session->s_cap_snaps_flushing);
1345		spin_unlock(&ci->i_ceph_lock);
1346
1347		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
1348		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
1349		send_cap_msg(session, ceph_vino(inode).ino, 0,
1350			     CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
1351			     capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
1352			     capsnap->size, 0,
1353			     &capsnap->mtime, &capsnap->atime,
1354			     capsnap->time_warp_seq,
1355			     capsnap->uid, capsnap->gid, capsnap->mode,
1356			     capsnap->xattr_version, capsnap->xattr_blob,
1357			     capsnap->follows);
1358
1359		next_follows = capsnap->follows + 1;
1360		ceph_put_cap_snap(capsnap);
 
 
 
 
 
1361
 
1362		spin_lock(&ci->i_ceph_lock);
1363		goto retry;
1364	}
 
1365
1366	/* we flushed them all; remove this inode from the queue */
1367	spin_lock(&mdsc->snap_flush_lock);
1368	list_del_init(&ci->i_snap_flush_item);
1369	spin_unlock(&mdsc->snap_flush_lock);
 
 
 
1370
1371out:
1372	if (psession)
1373		*psession = session;
1374	else if (session) {
1375		mutex_unlock(&session->s_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
1376		ceph_put_mds_session(session);
 
 
 
 
 
 
 
 
1377	}
1378}
1379
1380static void ceph_flush_snaps(struct ceph_inode_info *ci)
1381{
1382	spin_lock(&ci->i_ceph_lock);
1383	__ceph_flush_snaps(ci, NULL, 0);
 
 
1384	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
1385}
1386
1387/*
1388 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1389 * Caller is then responsible for calling __mark_inode_dirty with the
1390 * returned flags value.
1391 */
1392int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
 
1393{
1394	struct ceph_mds_client *mdsc =
1395		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1396	struct inode *inode = &ci->vfs_inode;
1397	int was = ci->i_dirty_caps;
1398	int dirty = 0;
1399
1400	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
 
 
 
 
 
 
 
 
 
1401	     ceph_cap_string(mask), ceph_cap_string(was),
1402	     ceph_cap_string(was | mask));
1403	ci->i_dirty_caps |= mask;
1404	if (was == 0) {
1405		if (!ci->i_head_snapc)
 
 
 
 
 
 
1406			ci->i_head_snapc = ceph_get_snap_context(
1407				ci->i_snap_realm->cached_context);
 
1408		dout(" inode %p now dirty snapc %p auth cap %p\n",
1409		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
1410		WARN_ON(!ci->i_auth_cap);
1411		BUG_ON(!list_empty(&ci->i_dirty_item));
1412		spin_lock(&mdsc->cap_dirty_lock);
1413		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1414		spin_unlock(&mdsc->cap_dirty_lock);
1415		if (ci->i_flushing_caps == 0) {
1416			ihold(inode);
1417			dirty |= I_DIRTY_SYNC;
1418		}
 
 
1419	}
1420	BUG_ON(list_empty(&ci->i_dirty_item));
1421	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1422	    (mask & CEPH_CAP_FILE_BUFFER))
1423		dirty |= I_DIRTY_DATASYNC;
1424	__cap_delay_requeue(mdsc, ci);
1425	return dirty;
1426}
1427
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1428/*
1429 * Add dirty inode to the flushing list.  Assigned a seq number so we
1430 * can wait for caps to flush without starving.
1431 *
1432 * Called under i_ceph_lock.
1433 */
1434static int __mark_caps_flushing(struct inode *inode,
1435				 struct ceph_mds_session *session)
 
1436{
1437	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1438	struct ceph_inode_info *ci = ceph_inode(inode);
 
1439	int flushing;
1440
 
1441	BUG_ON(ci->i_dirty_caps == 0);
1442	BUG_ON(list_empty(&ci->i_dirty_item));
 
1443
1444	flushing = ci->i_dirty_caps;
1445	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1446	     ceph_cap_string(flushing),
1447	     ceph_cap_string(ci->i_flushing_caps),
1448	     ceph_cap_string(ci->i_flushing_caps | flushing));
1449	ci->i_flushing_caps |= flushing;
1450	ci->i_dirty_caps = 0;
1451	dout(" inode %p now !dirty\n", inode);
1452
 
 
 
 
1453	spin_lock(&mdsc->cap_dirty_lock);
1454	list_del_init(&ci->i_dirty_item);
1455
1456	ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
 
 
 
1457	if (list_empty(&ci->i_flushing_item)) {
1458		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1459		mdsc->num_cap_flushing++;
1460		dout(" inode %p now flushing seq %lld\n", inode,
1461		     ci->i_cap_flush_seq);
1462	} else {
1463		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1464		dout(" inode %p now flushing (more) seq %lld\n", inode,
1465		     ci->i_cap_flush_seq);
1466	}
1467	spin_unlock(&mdsc->cap_dirty_lock);
1468
1469	return flushing;
 
 
1470}
1471
1472/*
1473 * try to invalidate mapping pages without blocking.
1474 */
1475static int try_nonblocking_invalidate(struct inode *inode)
 
 
1476{
1477	struct ceph_inode_info *ci = ceph_inode(inode);
1478	u32 invalidating_gen = ci->i_rdcache_gen;
1479
1480	spin_unlock(&ci->i_ceph_lock);
 
1481	invalidate_mapping_pages(&inode->i_data, 0, -1);
1482	spin_lock(&ci->i_ceph_lock);
1483
1484	if (inode->i_data.nrpages == 0 &&
1485	    invalidating_gen == ci->i_rdcache_gen) {
1486		/* success. */
1487		dout("try_nonblocking_invalidate %p success\n", inode);
1488		/* save any racing async invalidate some trouble */
1489		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1490		return 0;
1491	}
1492	dout("try_nonblocking_invalidate %p failed\n", inode);
1493	return -1;
1494}
1495
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1496/*
1497 * Swiss army knife function to examine currently used and wanted
1498 * versus held caps.  Release, flush, ack revoked caps to mds as
1499 * appropriate.
1500 *
1501 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1502 *    cap release further.
1503 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1504 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1505 *    further delay.
1506 */
1507void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1508		     struct ceph_mds_session *session)
1509{
1510	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1511	struct ceph_mds_client *mdsc = fsc->mdsc;
1512	struct inode *inode = &ci->vfs_inode;
1513	struct ceph_cap *cap;
 
1514	int file_wanted, used, cap_used;
1515	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1516	int issued, implemented, want, retain, revoking, flushing = 0;
1517	int mds = -1;   /* keep track of how far we've gone through i_caps list
1518			   to avoid an infinite loop on retry */
1519	struct rb_node *p;
1520	int tried_invalidate = 0;
1521	int delayed = 0, sent = 0, force_requeue = 0, num;
1522	int queue_invalidate = 0;
1523	int is_delayed = flags & CHECK_CAPS_NODELAY;
1524
1525	/* if we are unmounting, flush any unused caps immediately. */
1526	if (mdsc->stopping)
1527		is_delayed = 1;
1528
1529	spin_lock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
1530
1531	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1532		flags |= CHECK_CAPS_FLUSH;
1533
1534	/* flush snaps first time around only */
1535	if (!list_empty(&ci->i_cap_snaps))
1536		__ceph_flush_snaps(ci, &session, 0);
1537	goto retry_locked;
1538retry:
1539	spin_lock(&ci->i_ceph_lock);
1540retry_locked:
1541	file_wanted = __ceph_caps_file_wanted(ci);
 
 
1542	used = __ceph_caps_used(ci);
1543	want = file_wanted | used;
 
 
 
 
 
 
1544	issued = __ceph_caps_issued(ci, &implemented);
1545	revoking = implemented & ~issued;
1546
1547	retain = want | CEPH_CAP_PIN;
 
 
 
1548	if (!mdsc->stopping && inode->i_nlink > 0) {
1549		if (want) {
1550			retain |= CEPH_CAP_ANY;       /* be greedy */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1551		} else {
 
1552			retain |= CEPH_CAP_ANY_SHARED;
1553			/*
1554			 * keep RD only if we didn't have the file open RW,
1555			 * because then the mds would revoke it anyway to
1556			 * journal max_size=0.
1557			 */
1558			if (ci->i_max_size == 0)
1559				retain |= CEPH_CAP_ANY_RD;
1560		}
1561	}
1562
1563	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1564	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1565	     ceph_cap_string(file_wanted),
1566	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1567	     ceph_cap_string(ci->i_flushing_caps),
1568	     ceph_cap_string(issued), ceph_cap_string(revoking),
1569	     ceph_cap_string(retain),
1570	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1571	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1572	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1573
1574	/*
1575	 * If we no longer need to hold onto old our caps, and we may
1576	 * have cached pages, but don't want them, then try to invalidate.
1577	 * If we fail, it's because pages are locked.... try again later.
1578	 */
1579	if ((!is_delayed || mdsc->stopping) &&
1580	    ci->i_wrbuffer_ref == 0 &&               /* no dirty pages... */
1581	    inode->i_data.nrpages &&                 /* have cached pages */
1582	    (file_wanted == 0 ||                     /* no open files */
1583	     (revoking & (CEPH_CAP_FILE_CACHE|
1584			  CEPH_CAP_FILE_LAZYIO))) && /*  or revoking cache */
1585	    !tried_invalidate) {
1586		dout("check_caps trying to invalidate on %p\n", inode);
 
1587		if (try_nonblocking_invalidate(inode) < 0) {
1588			if (revoking & (CEPH_CAP_FILE_CACHE|
1589					CEPH_CAP_FILE_LAZYIO)) {
1590				dout("check_caps queuing invalidate\n");
1591				queue_invalidate = 1;
1592				ci->i_rdcache_revoking = ci->i_rdcache_gen;
1593			} else {
1594				dout("check_caps failed to invalidate pages\n");
1595				/* we failed to invalidate pages.  check these
1596				   caps again later. */
1597				force_requeue = 1;
1598				__cap_set_timeouts(mdsc, ci);
1599			}
1600		}
1601		tried_invalidate = 1;
1602		goto retry_locked;
1603	}
1604
1605	num = 0;
1606	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 
 
 
1607		cap = rb_entry(p, struct ceph_cap, ci_node);
1608		num++;
1609
1610		/* avoid looping forever */
1611		if (mds >= cap->mds ||
1612		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1613			continue;
1614
1615		/* NOTE: no side-effects allowed, until we take s_mutex */
1616
 
 
1617		cap_used = used;
1618		if (ci->i_auth_cap && cap != ci->i_auth_cap)
1619			cap_used &= ~ci->i_auth_cap->issued;
1620
1621		revoking = cap->implemented & ~cap->issued;
1622		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
1623		     cap->mds, cap, ceph_cap_string(cap->issued),
1624		     ceph_cap_string(cap_used),
1625		     ceph_cap_string(cap->implemented),
1626		     ceph_cap_string(revoking));
1627
1628		if (cap == ci->i_auth_cap &&
1629		    (cap->issued & CEPH_CAP_FILE_WR)) {
1630			/* request larger max_size from MDS? */
1631			if (ci->i_wanted_max_size > ci->i_max_size &&
1632			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1633				dout("requesting new max_size\n");
1634				goto ack;
1635			}
1636
1637			/* approaching file_max? */
1638			if ((inode->i_size << 1) >= ci->i_max_size &&
1639			    (ci->i_reported_size << 1) < ci->i_max_size) {
1640				dout("i_size approaching max_size\n");
1641				goto ack;
1642			}
1643		}
1644		/* flush anything dirty? */
1645		if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
1646		    ci->i_dirty_caps) {
1647			dout("flushing dirty caps\n");
1648			goto ack;
 
 
 
 
 
1649		}
1650
1651		/* completed revocation? going down and there are no caps? */
1652		if (revoking && (revoking & cap_used) == 0) {
1653			dout("completed revocation of %s\n",
1654			     ceph_cap_string(cap->implemented & ~cap->issued));
1655			goto ack;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1656		}
1657
1658		/* want more caps from mds? */
1659		if (want & ~(cap->mds_wanted | cap->issued))
1660			goto ack;
 
 
 
 
1661
1662		/* things we might delay */
1663		if ((cap->issued & ~retain) == 0 &&
1664		    cap->mds_wanted == want)
1665			continue;     /* nope, all good */
1666
1667		if (is_delayed)
1668			goto ack;
1669
1670		/* delay? */
1671		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1672		    time_before(jiffies, ci->i_hold_caps_max)) {
1673			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1674			     ceph_cap_string(cap->issued),
1675			     ceph_cap_string(cap->issued & retain),
1676			     ceph_cap_string(cap->mds_wanted),
1677			     ceph_cap_string(want));
1678			delayed++;
1679			continue;
1680		}
1681
1682ack:
1683		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1684			dout(" skipping %p I_NOFLUSH set\n", inode);
1685			continue;
1686		}
1687
1688		if (session && session != cap->session) {
1689			dout("oops, wrong session %p mutex\n", session);
1690			mutex_unlock(&session->s_mutex);
1691			session = NULL;
1692		}
1693		if (!session) {
1694			session = cap->session;
1695			if (mutex_trylock(&session->s_mutex) == 0) {
1696				dout("inverting session/ino locks on %p\n",
1697				     session);
1698				spin_unlock(&ci->i_ceph_lock);
1699				if (took_snap_rwsem) {
1700					up_read(&mdsc->snap_rwsem);
1701					took_snap_rwsem = 0;
1702				}
1703				mutex_lock(&session->s_mutex);
1704				goto retry;
1705			}
1706		}
1707		/* take snap_rwsem after session mutex */
1708		if (!took_snap_rwsem) {
1709			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1710				dout("inverting snap/in locks on %p\n",
1711				     inode);
1712				spin_unlock(&ci->i_ceph_lock);
1713				down_read(&mdsc->snap_rwsem);
1714				took_snap_rwsem = 1;
1715				goto retry;
1716			}
1717			took_snap_rwsem = 1;
1718		}
1719
1720		if (cap == ci->i_auth_cap && ci->i_dirty_caps)
1721			flushing = __mark_caps_flushing(inode, session);
1722		else
 
 
 
 
 
1723			flushing = 0;
 
 
 
 
 
1724
1725		mds = cap->mds;  /* remember mds, so we don't repeat */
1726		sent++;
1727
1728		/* __send_cap drops i_ceph_lock */
1729		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, cap_used,
1730				      want, retain, flushing, NULL);
 
 
 
 
1731		goto retry; /* retake i_ceph_lock and restart our cap scan. */
1732	}
1733
1734	/*
1735	 * Reschedule delayed caps release if we delayed anything,
1736	 * otherwise cancel.
1737	 */
1738	if (delayed && is_delayed)
1739		force_requeue = 1;   /* __send_cap delayed release; requeue */
1740	if (!delayed && !is_delayed)
1741		__cap_delay_cancel(mdsc, ci);
1742	else if (!is_delayed || force_requeue)
1743		__cap_delay_requeue(mdsc, ci);
 
1744
1745	spin_unlock(&ci->i_ceph_lock);
1746
 
 
 
1747	if (queue_invalidate)
1748		ceph_queue_invalidate(inode);
1749
1750	if (session)
1751		mutex_unlock(&session->s_mutex);
1752	if (took_snap_rwsem)
1753		up_read(&mdsc->snap_rwsem);
1754}
1755
1756/*
1757 * Try to flush dirty caps back to the auth mds.
1758 */
1759static int try_flush_caps(struct inode *inode, unsigned *flush_tid)
1760{
1761	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1762	struct ceph_inode_info *ci = ceph_inode(inode);
1763	int flushing = 0;
1764	struct ceph_mds_session *session = NULL;
1765
1766retry:
1767	spin_lock(&ci->i_ceph_lock);
1768	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1769		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1770		goto out;
1771	}
1772	if (ci->i_dirty_caps && ci->i_auth_cap) {
1773		struct ceph_cap *cap = ci->i_auth_cap;
1774		int used = __ceph_caps_used(ci);
1775		int want = __ceph_caps_wanted(ci);
1776		int delayed;
1777
1778		if (!session || session != cap->session) {
1779			spin_unlock(&ci->i_ceph_lock);
1780			if (session)
1781				mutex_unlock(&session->s_mutex);
1782			session = cap->session;
1783			mutex_lock(&session->s_mutex);
1784			goto retry;
1785		}
1786		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
1787			goto out;
 
1788
1789		flushing = __mark_caps_flushing(inode, session);
1790
1791		/* __send_cap drops i_ceph_lock */
1792		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
1793				     cap->issued | cap->implemented, flushing,
1794				     flush_tid);
1795		if (!delayed)
1796			goto out_unlocked;
 
 
 
 
 
 
 
 
 
 
1797
1798		spin_lock(&ci->i_ceph_lock);
1799		__cap_delay_requeue(mdsc, ci);
 
 
 
 
 
 
 
 
 
1800	}
1801out:
1802	spin_unlock(&ci->i_ceph_lock);
1803out_unlocked:
1804	if (session)
1805		mutex_unlock(&session->s_mutex);
1806	return flushing;
1807}
1808
1809/*
1810 * Return true if we've flushed caps through the given flush_tid.
1811 */
1812static int caps_are_flushed(struct inode *inode, unsigned tid)
1813{
1814	struct ceph_inode_info *ci = ceph_inode(inode);
1815	int i, ret = 1;
1816
1817	spin_lock(&ci->i_ceph_lock);
1818	for (i = 0; i < CEPH_CAP_BITS; i++)
1819		if ((ci->i_flushing_caps & (1 << i)) &&
1820		    ci->i_cap_flush_tid[i] <= tid) {
1821			/* still flushing this bit */
 
1822			ret = 0;
1823			break;
1824		}
1825	spin_unlock(&ci->i_ceph_lock);
1826	return ret;
1827}
1828
1829/*
1830 * Wait on any unsafe replies for the given inode.  First wait on the
1831 * newest request, and make that the upper bound.  Then, if there are
1832 * more requests, keep waiting on the oldest as long as it is still older
1833 * than the original request.
1834 */
1835static void sync_write_wait(struct inode *inode)
1836{
 
1837	struct ceph_inode_info *ci = ceph_inode(inode);
1838	struct list_head *head = &ci->i_unsafe_writes;
1839	struct ceph_osd_request *req;
1840	u64 last_tid;
1841
1842	spin_lock(&ci->i_unsafe_lock);
1843	if (list_empty(head))
1844		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1845
1846	/* set upper bound as _last_ entry in chain */
1847	req = list_entry(head->prev, struct ceph_osd_request,
1848			 r_unsafe_item);
1849	last_tid = req->r_tid;
 
 
 
 
 
1850
1851	do {
1852		ceph_osdc_get_request(req);
1853		spin_unlock(&ci->i_unsafe_lock);
1854		dout("sync_write_wait on tid %llu (until %llu)\n",
1855		     req->r_tid, last_tid);
1856		wait_for_completion(&req->r_safe_completion);
1857		spin_lock(&ci->i_unsafe_lock);
1858		ceph_osdc_put_request(req);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1859
1860		/*
1861		 * from here on look at first entry in chain, since we
1862		 * only want to wait for anything older than last_tid
1863		 */
1864		if (list_empty(head))
1865			break;
1866		req = list_entry(head->next, struct ceph_osd_request,
1867				 r_unsafe_item);
1868	} while (req->r_tid < last_tid);
1869out:
1870	spin_unlock(&ci->i_unsafe_lock);
 
 
 
 
1871}
1872
1873int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
1874{
1875	struct inode *inode = file->f_mapping->host;
1876	struct ceph_inode_info *ci = ceph_inode(inode);
1877	unsigned flush_tid;
1878	int ret;
1879	int dirty;
1880
1881	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
1882	sync_write_wait(inode);
1883
1884	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1885	if (ret < 0)
1886		return ret;
1887	mutex_lock(&inode->i_mutex);
 
 
 
1888
1889	dirty = try_flush_caps(inode, &flush_tid);
1890	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
1891
 
 
1892	/*
1893	 * only wait on non-file metadata writeback (the mds
1894	 * can recover size and mtime, so we don't need to
1895	 * wait for that)
1896	 */
1897	if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
1898		dout("fsync waiting for flush_tid %u\n", flush_tid);
1899		ret = wait_event_interruptible(ci->i_cap_wq,
1900				       caps_are_flushed(inode, flush_tid));
1901	}
1902
1903	dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
1904	mutex_unlock(&inode->i_mutex);
 
 
 
 
 
 
1905	return ret;
1906}
1907
1908/*
1909 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
1910 * queue inode for flush but don't do so immediately, because we can
1911 * get by with fewer MDS messages if we wait for data writeback to
1912 * complete first.
1913 */
1914int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
1915{
1916	struct ceph_inode_info *ci = ceph_inode(inode);
1917	unsigned flush_tid;
1918	int err = 0;
1919	int dirty;
1920	int wait = wbc->sync_mode == WB_SYNC_ALL;
1921
1922	dout("write_inode %p wait=%d\n", inode, wait);
 
1923	if (wait) {
 
 
 
1924		dirty = try_flush_caps(inode, &flush_tid);
1925		if (dirty)
1926			err = wait_event_interruptible(ci->i_cap_wq,
1927				       caps_are_flushed(inode, flush_tid));
1928	} else {
1929		struct ceph_mds_client *mdsc =
1930			ceph_sb_to_client(inode->i_sb)->mdsc;
1931
1932		spin_lock(&ci->i_ceph_lock);
1933		if (__ceph_caps_dirty(ci))
1934			__cap_delay_requeue_front(mdsc, ci);
1935		spin_unlock(&ci->i_ceph_lock);
1936	}
1937	return err;
1938}
1939
1940/*
1941 * After a recovering MDS goes active, we need to resend any caps
1942 * we were flushing.
1943 *
1944 * Caller holds session->s_mutex.
1945 */
1946static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1947				   struct ceph_mds_session *session)
1948{
1949	struct ceph_cap_snap *capsnap;
 
 
1950
1951	dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
1952	list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
1953			    flushing_item) {
1954		struct ceph_inode_info *ci = capsnap->ci;
1955		struct inode *inode = &ci->vfs_inode;
1956		struct ceph_cap *cap;
1957
 
1958		spin_lock(&ci->i_ceph_lock);
1959		cap = ci->i_auth_cap;
1960		if (cap && cap->session == session) {
1961			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
1962			     cap, capsnap);
1963			__ceph_flush_snaps(ci, &session, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1964		} else {
1965			pr_err("%p auth cap %p not mds%d ???\n", inode,
1966			       cap, session->s_mds);
1967		}
 
1968		spin_unlock(&ci->i_ceph_lock);
1969	}
1970}
1971
1972void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
1973			     struct ceph_mds_session *session)
1974{
1975	struct ceph_inode_info *ci;
 
 
1976
1977	kick_flushing_capsnaps(mdsc, session);
1978
1979	dout("kick_flushing_caps mds%d\n", session->s_mds);
1980	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
1981		struct inode *inode = &ci->vfs_inode;
1982		struct ceph_cap *cap;
1983		int delayed = 0;
1984
 
 
 
 
 
1985		spin_lock(&ci->i_ceph_lock);
1986		cap = ci->i_auth_cap;
1987		if (cap && cap->session == session) {
1988			dout("kick_flushing_caps %p cap %p %s\n", inode,
1989			     cap, ceph_cap_string(ci->i_flushing_caps));
1990			delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1991					     __ceph_caps_used(ci),
1992					     __ceph_caps_wanted(ci),
1993					     cap->issued | cap->implemented,
1994					     ci->i_flushing_caps, NULL);
1995			if (delayed) {
1996				spin_lock(&ci->i_ceph_lock);
1997				__cap_delay_requeue(mdsc, ci);
1998				spin_unlock(&ci->i_ceph_lock);
1999			}
2000		} else {
2001			pr_err("%p auth cap %p not mds%d ???\n", inode,
2002			       cap, session->s_mds);
2003			spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
2004		}
 
2005	}
2006}
2007
2008static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
2009				     struct ceph_mds_session *session,
2010				     struct inode *inode)
2011{
2012	struct ceph_inode_info *ci = ceph_inode(inode);
2013	struct ceph_cap *cap;
2014	int delayed = 0;
2015
2016	spin_lock(&ci->i_ceph_lock);
2017	cap = ci->i_auth_cap;
2018	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
2019	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
2020
2021	__ceph_flush_snaps(ci, &session, 1);
 
2022
2023	if (ci->i_flushing_caps) {
 
2024		spin_lock(&mdsc->cap_dirty_lock);
2025		list_move_tail(&ci->i_flushing_item,
2026			       &cap->session->s_cap_flushing);
 
2027		spin_unlock(&mdsc->cap_dirty_lock);
2028
2029		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
2030				     __ceph_caps_used(ci),
2031				     __ceph_caps_wanted(ci),
2032				     cap->issued | cap->implemented,
2033				     ci->i_flushing_caps, NULL);
2034		if (delayed) {
2035			spin_lock(&ci->i_ceph_lock);
2036			__cap_delay_requeue(mdsc, ci);
2037			spin_unlock(&ci->i_ceph_lock);
2038		}
2039	} else {
2040		spin_unlock(&ci->i_ceph_lock);
2041	}
2042}
2043
2044
2045/*
2046 * Take references to capabilities we hold, so that we don't release
2047 * them to the MDS prematurely.
2048 *
2049 * Protected by i_ceph_lock.
2050 */
2051static void __take_cap_refs(struct ceph_inode_info *ci, int got)
 
2052{
 
 
2053	if (got & CEPH_CAP_PIN)
2054		ci->i_pin_ref++;
2055	if (got & CEPH_CAP_FILE_RD)
2056		ci->i_rd_ref++;
2057	if (got & CEPH_CAP_FILE_CACHE)
2058		ci->i_rdcache_ref++;
2059	if (got & CEPH_CAP_FILE_WR)
 
 
 
 
 
 
 
2060		ci->i_wr_ref++;
 
2061	if (got & CEPH_CAP_FILE_BUFFER) {
2062		if (ci->i_wb_ref == 0)
2063			ihold(&ci->vfs_inode);
2064		ci->i_wb_ref++;
2065		dout("__take_cap_refs %p wb %d -> %d (?)\n",
2066		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2067	}
2068}
2069
2070/*
2071 * Try to grab cap references.  Specify those refs we @want, and the
2072 * minimal set we @need.  Also include the larger offset we are writing
2073 * to (when applicable), and check against max_size here as well.
2074 * Note that caller is responsible for ensuring max_size increases are
2075 * requested from the MDS.
2076 */
2077static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
2078			    int *got, loff_t endoff, int *check_max, int *err)
 
 
 
 
 
 
 
 
 
 
 
 
2079{
2080	struct inode *inode = &ci->vfs_inode;
 
2081	int ret = 0;
2082	int have, implemented;
2083	int file_wanted;
2084
2085	dout("get_cap_refs %p need %s want %s\n", inode,
2086	     ceph_cap_string(need), ceph_cap_string(want));
 
 
2087	spin_lock(&ci->i_ceph_lock);
2088
2089	/* make sure file is actually open */
2090	file_wanted = __ceph_caps_file_wanted(ci);
2091	if ((file_wanted & need) == 0) {
2092		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2093		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2094		*err = -EBADF;
2095		ret = 1;
2096		goto out;
2097	}
2098
2099	/* finish pending truncate */
2100	while (ci->i_truncate_pending) {
2101		spin_unlock(&ci->i_ceph_lock);
 
 
 
 
2102		__ceph_do_pending_vmtruncate(inode);
2103		spin_lock(&ci->i_ceph_lock);
2104	}
2105
2106	have = __ceph_caps_issued(ci, &implemented);
2107
2108	if (have & need & CEPH_CAP_FILE_WR) {
2109		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2110			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2111			     inode, endoff, ci->i_max_size);
2112			if (endoff > ci->i_requested_max_size) {
2113				*check_max = 1;
2114				ret = 1;
2115			}
2116			goto out;
2117		}
2118		/*
2119		 * If a sync write is in progress, we must wait, so that we
2120		 * can get a final snapshot value for size+mtime.
2121		 */
2122		if (__ceph_have_pending_cap_snap(ci)) {
2123			dout("get_cap_refs %p cap_snap_pending\n", inode);
2124			goto out;
2125		}
2126	}
2127
2128	if ((have & need) == need) {
2129		/*
2130		 * Look at (implemented & ~have & not) so that we keep waiting
2131		 * on transition from wanted -> needed caps.  This is needed
2132		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2133		 * going before a prior buffered writeback happens.
 
 
 
2134		 */
2135		int not = want & ~(have & need);
2136		int revoking = implemented & ~have;
 
2137		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2138		     inode, ceph_cap_string(have), ceph_cap_string(not),
2139		     ceph_cap_string(revoking));
2140		if ((revoking & not) == 0) {
2141			*got = need | (have & want);
2142			__take_cap_refs(ci, *got);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2143			ret = 1;
2144		}
2145	} else {
2146		dout("get_cap_refs %p have %s needed %s\n", inode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2147		     ceph_cap_string(have), ceph_cap_string(need));
2148	}
2149out:
 
 
 
2150	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
2151	dout("get_cap_refs %p ret %d got %s\n", inode,
2152	     ret, ceph_cap_string(*got));
2153	return ret;
2154}
2155
2156/*
2157 * Check the offset we are writing up to against our current
2158 * max_size.  If necessary, tell the MDS we want to write to
2159 * a larger offset.
2160 */
2161static void check_max_size(struct inode *inode, loff_t endoff)
2162{
2163	struct ceph_inode_info *ci = ceph_inode(inode);
2164	int check = 0;
2165
2166	/* do we need to explicitly request a larger max_size? */
2167	spin_lock(&ci->i_ceph_lock);
2168	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
2169		dout("write %p at large endoff %llu, req max_size\n",
2170		     inode, endoff);
2171		ci->i_wanted_max_size = endoff;
2172	}
2173	/* duplicate ceph_check_caps()'s logic */
2174	if (ci->i_auth_cap &&
2175	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2176	    ci->i_wanted_max_size > ci->i_max_size &&
2177	    ci->i_wanted_max_size > ci->i_requested_max_size)
2178		check = 1;
2179	spin_unlock(&ci->i_ceph_lock);
2180	if (check)
2181		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2182}
2183
2184/*
2185 * Wait for caps, and take cap references.  If we can't get a WR cap
2186 * due to a small max_size, make sure we check_max_size (and possibly
2187 * ask the mds) so we don't get hung up indefinitely.
2188 */
2189int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got,
2190		  loff_t endoff)
2191{
2192	int check_max, ret, err;
 
 
 
 
2193
2194retry:
2195	if (endoff > 0)
2196		check_max_size(&ci->vfs_inode, endoff);
2197	check_max = 0;
2198	err = 0;
2199	ret = wait_event_interruptible(ci->i_cap_wq,
2200				       try_get_cap_refs(ci, need, want,
2201							got, endoff,
2202							&check_max, &err));
2203	if (err)
2204		ret = err;
2205	if (check_max)
2206		goto retry;
2207	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2208}
2209
2210/*
2211 * Take cap refs.  Caller must already know we hold at least one ref
2212 * on the caps in question or we don't know this is safe.
2213 */
2214void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2215{
2216	spin_lock(&ci->i_ceph_lock);
2217	__take_cap_refs(ci, caps);
2218	spin_unlock(&ci->i_ceph_lock);
2219}
2220
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2221/*
2222 * Release cap refs.
2223 *
2224 * If we released the last ref on any given cap, call ceph_check_caps
2225 * to release (or schedule a release).
2226 *
2227 * If we are releasing a WR cap (from a sync write), finalize any affected
2228 * cap_snap, and wake up any waiters.
2229 */
2230void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 
2231{
2232	struct inode *inode = &ci->vfs_inode;
2233	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2234	struct ceph_cap_snap *capsnap;
2235
2236	spin_lock(&ci->i_ceph_lock);
2237	if (had & CEPH_CAP_PIN)
2238		--ci->i_pin_ref;
2239	if (had & CEPH_CAP_FILE_RD)
2240		if (--ci->i_rd_ref == 0)
2241			last++;
2242	if (had & CEPH_CAP_FILE_CACHE)
2243		if (--ci->i_rdcache_ref == 0)
2244			last++;
 
 
 
2245	if (had & CEPH_CAP_FILE_BUFFER) {
2246		if (--ci->i_wb_ref == 0) {
2247			last++;
 
2248			put++;
 
2249		}
2250		dout("put_cap_refs %p wb %d -> %d (?)\n",
2251		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2252	}
2253	if (had & CEPH_CAP_FILE_WR)
2254		if (--ci->i_wr_ref == 0) {
2255			last++;
2256			if (!list_empty(&ci->i_cap_snaps)) {
2257				capsnap = list_first_entry(&ci->i_cap_snaps,
2258						     struct ceph_cap_snap,
2259						     ci_item);
2260				if (capsnap->writing) {
2261					capsnap->writing = 0;
2262					flushsnaps =
2263						__ceph_finish_cap_snap(ci,
2264								       capsnap);
2265					wake = 1;
2266				}
2267			}
 
 
 
2268		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2269	spin_unlock(&ci->i_ceph_lock);
2270
2271	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2272	     last ? " last" : "", put ? " put" : "");
2273
2274	if (last && !flushsnaps)
2275		ceph_check_caps(ci, 0, NULL);
2276	else if (flushsnaps)
2277		ceph_flush_snaps(ci);
 
 
 
 
 
 
 
 
 
 
 
 
2278	if (wake)
2279		wake_up_all(&ci->i_cap_wq);
2280	if (put)
2281		iput(inode);
2282}
2283
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2284/*
2285 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2286 * context.  Adjust per-snap dirty page accounting as appropriate.
2287 * Once all dirty data for a cap_snap is flushed, flush snapped file
2288 * metadata back to the MDS.  If we dropped the last ref, call
2289 * ceph_check_caps.
2290 */
2291void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2292				struct ceph_snap_context *snapc)
2293{
2294	struct inode *inode = &ci->vfs_inode;
2295	int last = 0;
2296	int complete_capsnap = 0;
2297	int drop_capsnap = 0;
2298	int found = 0;
2299	struct ceph_cap_snap *capsnap = NULL;
2300
2301	spin_lock(&ci->i_ceph_lock);
2302	ci->i_wrbuffer_ref -= nr;
2303	last = !ci->i_wrbuffer_ref;
 
 
 
2304
2305	if (ci->i_head_snapc == snapc) {
2306		ci->i_wrbuffer_ref_head -= nr;
2307		if (ci->i_wrbuffer_ref_head == 0 &&
2308		    ci->i_dirty_caps == 0 && ci->i_flushing_caps == 0) {
 
 
2309			BUG_ON(!ci->i_head_snapc);
2310			ceph_put_snap_context(ci->i_head_snapc);
2311			ci->i_head_snapc = NULL;
2312		}
2313		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2314		     inode,
2315		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2316		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2317		     last ? " LAST" : "");
2318	} else {
2319		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2320			if (capsnap->context == snapc) {
2321				found = 1;
2322				break;
2323			}
2324		}
2325		BUG_ON(!found);
 
 
 
 
 
 
 
 
 
2326		capsnap->dirty_pages -= nr;
2327		if (capsnap->dirty_pages == 0) {
2328			complete_capsnap = 1;
2329			if (capsnap->dirty == 0)
2330				/* cap writeback completed before we created
2331				 * the cap_snap; no FLUSHSNAP is needed */
2332				drop_capsnap = 1;
 
 
 
 
2333		}
2334		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2335		     " snap %lld %d/%d -> %d/%d %s%s%s\n",
2336		     inode, capsnap, capsnap->context->seq,
2337		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2338		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2339		     last ? " (wrbuffer last)" : "",
2340		     complete_capsnap ? " (complete capsnap)" : "",
2341		     drop_capsnap ? " (drop capsnap)" : "");
2342		if (drop_capsnap) {
2343			ceph_put_snap_context(capsnap->context);
2344			list_del(&capsnap->ci_item);
2345			list_del(&capsnap->flushing_item);
2346			ceph_put_cap_snap(capsnap);
2347		}
2348	}
2349
 
2350	spin_unlock(&ci->i_ceph_lock);
2351
2352	if (last) {
2353		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2354		iput(inode);
2355	} else if (complete_capsnap) {
2356		ceph_flush_snaps(ci);
2357		wake_up_all(&ci->i_cap_wq);
2358	}
2359	if (drop_capsnap)
 
 
2360		iput(inode);
 
2361}
2362
2363/*
2364 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
2365 */
2366static void invalidate_aliases(struct inode *inode)
2367{
2368	struct dentry *dn, *prev = NULL;
2369
2370	dout("invalidate_aliases inode %p\n", inode);
2371	d_prune_aliases(inode);
2372	/*
2373	 * For non-directory inode, d_find_alias() only returns
2374	 * hashed dentry. After calling d_invalidate(), the
2375	 * dentry becomes unhashed.
2376	 *
2377	 * For directory inode, d_find_alias() can return
2378	 * unhashed dentry. But directory inode should have
2379	 * one alias at most.
2380	 */
2381	while ((dn = d_find_alias(inode))) {
2382		if (dn == prev) {
2383			dput(dn);
2384			break;
2385		}
2386		d_invalidate(dn);
2387		if (prev)
2388			dput(prev);
2389		prev = dn;
2390	}
2391	if (prev)
2392		dput(prev);
2393}
2394
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2395/*
2396 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
2397 * actually be a revocation if it specifies a smaller cap set.)
2398 *
2399 * caller holds s_mutex and i_ceph_lock, we drop both.
2400 *
2401 * return value:
2402 *  0 - ok
2403 *  1 - check_caps on auth cap only (writeback)
2404 *  2 - check_caps (ack revoke)
2405 */
2406static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
2407			     struct ceph_mds_session *session,
2408			     struct ceph_cap *cap,
2409			     struct ceph_buffer *xattr_buf)
2410		__releases(ci->i_ceph_lock)
 
 
 
2411{
2412	struct ceph_inode_info *ci = ceph_inode(inode);
2413	int mds = session->s_mds;
2414	int seq = le32_to_cpu(grant->seq);
2415	int newcaps = le32_to_cpu(grant->caps);
2416	int issued, implemented, used, wanted, dirty;
2417	u64 size = le64_to_cpu(grant->size);
2418	u64 max_size = le64_to_cpu(grant->max_size);
2419	struct timespec mtime, atime, ctime;
2420	int check_caps = 0;
2421	int wake = 0;
2422	int writeback = 0;
2423	int queue_invalidate = 0;
2424	int deleted_inode = 0;
2425	int queue_revalidate = 0;
 
2426
2427	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
2428	     inode, cap, mds, seq, ceph_cap_string(newcaps));
2429	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2430		inode->i_size);
2431
2432
2433	/*
2434	 * auth mds of the inode changed. we received the cap export message,
2435	 * but still haven't received the cap import message. handle_cap_export
2436	 * updated the new auth MDS' cap.
2437	 *
2438	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
2439	 * that was sent before the cap import message. So don't remove caps.
2440	 */
2441	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
2442		WARN_ON(cap != ci->i_auth_cap);
2443		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
2444		seq = cap->seq;
2445		newcaps |= cap->issued;
2446	}
2447
2448	/*
2449	 * If CACHE is being revoked, and we have no dirty buffers,
2450	 * try to invalidate (once).  (If there are dirty buffers, we
2451	 * will invalidate _after_ writeback.)
2452	 */
2453	if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
 
2454	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2455	    !ci->i_wrbuffer_ref) {
2456		if (try_nonblocking_invalidate(inode)) {
2457			/* there were locked pages.. invalidate later
2458			   in a separate thread. */
2459			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2460				queue_invalidate = 1;
2461				ci->i_rdcache_revoking = ci->i_rdcache_gen;
2462			}
2463		}
2464
2465		ceph_fscache_invalidate(inode);
2466	}
2467
2468	/* side effects now are allowed */
 
2469
2470	issued = __ceph_caps_issued(ci, &implemented);
2471	issued |= implemented | __ceph_caps_dirty(ci);
 
 
 
 
 
 
 
 
 
 
 
 
2472
2473	cap->cap_gen = session->s_cap_gen;
 
2474	cap->seq = seq;
2475
2476	__check_cap_issue(ci, cap, newcaps);
2477
2478	if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
2479		inode->i_mode = le32_to_cpu(grant->mode);
 
 
 
 
 
 
 
 
 
2480		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
2481		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
 
2482		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2483		     from_kuid(&init_user_ns, inode->i_uid),
2484		     from_kgid(&init_user_ns, inode->i_gid));
2485	}
2486
2487	if ((issued & CEPH_CAP_LINK_EXCL) == 0) {
 
2488		set_nlink(inode, le32_to_cpu(grant->nlink));
2489		if (inode->i_nlink == 0 &&
2490		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
2491			deleted_inode = 1;
2492	}
2493
2494	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
 
2495		int len = le32_to_cpu(grant->xattr_len);
2496		u64 version = le64_to_cpu(grant->xattr_version);
2497
2498		if (version > ci->i_xattrs.version) {
2499			dout(" got new xattrs v%llu on %p len %d\n",
2500			     version, inode, len);
2501			if (ci->i_xattrs.blob)
2502				ceph_buffer_put(ci->i_xattrs.blob);
2503			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2504			ci->i_xattrs.version = version;
2505			ceph_forget_all_cached_acls(inode);
 
2506		}
2507	}
2508
2509	/* Do we need to revalidate our fscache cookie. Don't bother on the
2510	 * first cache cap as we already validate at cookie creation time. */
2511	if ((issued & CEPH_CAP_FILE_CACHE) && ci->i_rdcache_gen > 1)
2512		queue_revalidate = 1;
2513
2514	/* size/ctime/mtime/atime? */
2515	ceph_fill_file_size(inode, issued,
2516			    le32_to_cpu(grant->truncate_seq),
2517			    le64_to_cpu(grant->truncate_size), size);
2518	ceph_decode_timespec(&mtime, &grant->mtime);
2519	ceph_decode_timespec(&atime, &grant->atime);
2520	ceph_decode_timespec(&ctime, &grant->ctime);
2521	ceph_fill_file_time(inode, issued,
2522			    le32_to_cpu(grant->time_warp_seq), &ctime, &mtime,
2523			    &atime);
2524
2525
2526	/* file layout may have changed */
2527	ci->i_layout = grant->layout;
2528
2529	/* max size increase? */
2530	if (ci->i_auth_cap == cap && max_size != ci->i_max_size) {
2531		dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
2532		ci->i_max_size = max_size;
2533		if (max_size >= ci->i_wanted_max_size) {
2534			ci->i_wanted_max_size = 0;  /* reset */
2535			ci->i_requested_max_size = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2536		}
2537		wake = 1;
2538	}
2539
2540	/* check cap bits */
2541	wanted = __ceph_caps_wanted(ci);
2542	used = __ceph_caps_used(ci);
2543	dirty = __ceph_caps_dirty(ci);
2544	dout(" my wanted = %s, used = %s, dirty %s\n",
2545	     ceph_cap_string(wanted),
2546	     ceph_cap_string(used),
2547	     ceph_cap_string(dirty));
2548	if (wanted != le32_to_cpu(grant->wanted)) {
2549		dout("mds wanted %s -> %s\n",
2550		     ceph_cap_string(le32_to_cpu(grant->wanted)),
2551		     ceph_cap_string(wanted));
2552		/* imported cap may not have correct mds_wanted */
2553		if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT)
2554			check_caps = 1;
 
 
 
 
 
 
 
2555	}
2556
2557	/* revocation, grant, or no-op? */
2558	if (cap->issued & ~newcaps) {
2559		int revoking = cap->issued & ~newcaps;
2560
2561		dout("revocation: %s -> %s (revoking %s)\n",
2562		     ceph_cap_string(cap->issued),
2563		     ceph_cap_string(newcaps),
2564		     ceph_cap_string(revoking));
2565		if (revoking & used & CEPH_CAP_FILE_BUFFER)
2566			writeback = 1;  /* initiate writeback; will delay ack */
2567		else if (revoking == CEPH_CAP_FILE_CACHE &&
2568			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2569			 queue_invalidate)
 
2570			; /* do nothing yet, invalidation will be queued */
2571		else if (cap == ci->i_auth_cap)
2572			check_caps = 1; /* check auth cap only */
2573		else
2574			check_caps = 2; /* check all caps */
 
 
 
2575		cap->issued = newcaps;
2576		cap->implemented |= newcaps;
2577	} else if (cap->issued == newcaps) {
2578		dout("caps unchanged: %s -> %s\n",
2579		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
2580	} else {
2581		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
2582		     ceph_cap_string(newcaps));
2583		/* non-auth MDS is revoking the newly grant caps ? */
2584		if (cap == ci->i_auth_cap &&
2585		    __ceph_caps_revoking_other(ci, cap, newcaps))
2586		    check_caps = 2;
2587
2588		cap->issued = newcaps;
2589		cap->implemented |= newcaps; /* add bits only, to
2590					      * avoid stepping on a
2591					      * pending revocation */
2592		wake = 1;
2593	}
2594	BUG_ON(cap->issued & ~cap->implemented);
2595
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2596	spin_unlock(&ci->i_ceph_lock);
2597
 
 
 
 
 
 
 
2598	if (writeback)
2599		/*
2600		 * queue inode for writeback: we can't actually call
2601		 * filemap_write_and_wait, etc. from message handler
2602		 * context.
2603		 */
2604		ceph_queue_writeback(inode);
2605	if (queue_invalidate)
2606		ceph_queue_invalidate(inode);
2607	if (deleted_inode)
2608		invalidate_aliases(inode);
2609	if (queue_revalidate)
2610		ceph_queue_revalidate(inode);
2611	if (wake)
2612		wake_up_all(&ci->i_cap_wq);
2613
 
2614	if (check_caps == 1)
2615		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
2616				session);
2617	else if (check_caps == 2)
2618		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
2619	else
2620		mutex_unlock(&session->s_mutex);
2621}
2622
2623/*
2624 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
2625 * MDS has been safely committed.
2626 */
2627static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
2628				 struct ceph_mds_caps *m,
2629				 struct ceph_mds_session *session,
2630				 struct ceph_cap *cap)
2631	__releases(ci->i_ceph_lock)
2632{
2633	struct ceph_inode_info *ci = ceph_inode(inode);
2634	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 
 
2635	unsigned seq = le32_to_cpu(m->seq);
2636	int dirty = le32_to_cpu(m->dirty);
2637	int cleaned = 0;
2638	int drop = 0;
2639	int i;
 
 
 
 
 
 
 
 
 
 
2640
2641	for (i = 0; i < CEPH_CAP_BITS; i++)
2642		if ((dirty & (1 << i)) &&
2643		    flush_tid == ci->i_cap_flush_tid[i])
2644			cleaned |= 1 << i;
 
 
 
 
 
 
 
 
 
 
 
 
 
2645
2646	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
2647	     " flushing %s -> %s\n",
2648	     inode, session->s_mds, seq, ceph_cap_string(dirty),
2649	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
2650	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
2651
2652	if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
2653		goto out;
2654
2655	ci->i_flushing_caps &= ~cleaned;
2656
2657	spin_lock(&mdsc->cap_dirty_lock);
 
 
 
 
2658	if (ci->i_flushing_caps == 0) {
2659		list_del_init(&ci->i_flushing_item);
2660		if (!list_empty(&session->s_cap_flushing))
2661			dout(" mds%d still flushing cap on %p\n",
2662			     session->s_mds,
2663			     &list_entry(session->s_cap_flushing.next,
2664					 struct ceph_inode_info,
2665					 i_flushing_item)->vfs_inode);
 
 
 
2666		mdsc->num_cap_flushing--;
2667		wake_up_all(&mdsc->cap_flushing_wq);
2668		dout(" inode %p now !flushing\n", inode);
2669
2670		if (ci->i_dirty_caps == 0) {
2671			dout(" inode %p now clean\n", inode);
2672			BUG_ON(!list_empty(&ci->i_dirty_item));
2673			drop = 1;
2674			if (ci->i_wrbuffer_ref_head == 0) {
 
2675				BUG_ON(!ci->i_head_snapc);
2676				ceph_put_snap_context(ci->i_head_snapc);
2677				ci->i_head_snapc = NULL;
2678			}
2679		} else {
2680			BUG_ON(list_empty(&ci->i_dirty_item));
2681		}
2682	}
2683	spin_unlock(&mdsc->cap_dirty_lock);
2684	wake_up_all(&ci->i_cap_wq);
2685
2686out:
2687	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
2688	if (drop)
2689		iput(inode);
2690}
2691
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2692/*
2693 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
2694 * throw away our cap_snap.
2695 *
2696 * Caller hold s_mutex.
2697 */
2698static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
2699				     struct ceph_mds_caps *m,
2700				     struct ceph_mds_session *session)
2701{
2702	struct ceph_inode_info *ci = ceph_inode(inode);
 
2703	u64 follows = le64_to_cpu(m->snap_follows);
2704	struct ceph_cap_snap *capsnap;
2705	int drop = 0;
 
2706
2707	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
2708	     inode, ci, session->s_mds, follows);
2709
2710	spin_lock(&ci->i_ceph_lock);
2711	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2712		if (capsnap->follows == follows) {
2713			if (capsnap->flush_tid != flush_tid) {
2714				dout(" cap_snap %p follows %lld tid %lld !="
2715				     " %lld\n", capsnap, follows,
2716				     flush_tid, capsnap->flush_tid);
2717				break;
2718			}
2719			WARN_ON(capsnap->dirty_pages || capsnap->writing);
2720			dout(" removing %p cap_snap %p follows %lld\n",
2721			     inode, capsnap, follows);
2722			ceph_put_snap_context(capsnap->context);
2723			list_del(&capsnap->ci_item);
2724			list_del(&capsnap->flushing_item);
2725			ceph_put_cap_snap(capsnap);
2726			drop = 1;
2727			break;
2728		} else {
2729			dout(" skipping cap_snap %p follows %lld\n",
2730			     capsnap, capsnap->follows);
2731		}
2732	}
 
 
2733	spin_unlock(&ci->i_ceph_lock);
2734	if (drop)
 
 
 
 
 
 
 
2735		iput(inode);
 
2736}
2737
2738/*
2739 * Handle TRUNC from MDS, indicating file truncation.
2740 *
2741 * caller hold s_mutex.
2742 */
2743static void handle_cap_trunc(struct inode *inode,
2744			     struct ceph_mds_caps *trunc,
2745			     struct ceph_mds_session *session)
2746	__releases(ci->i_ceph_lock)
2747{
2748	struct ceph_inode_info *ci = ceph_inode(inode);
2749	int mds = session->s_mds;
2750	int seq = le32_to_cpu(trunc->seq);
2751	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
2752	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
2753	u64 size = le64_to_cpu(trunc->size);
2754	int implemented = 0;
2755	int dirty = __ceph_caps_dirty(ci);
2756	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
2757	int queue_trunc = 0;
 
 
2758
2759	issued |= implemented | dirty;
2760
2761	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
2762	     inode, mds, seq, truncate_size, truncate_seq);
2763	queue_trunc = ceph_fill_file_size(inode, issued,
2764					  truncate_seq, truncate_size, size);
2765	spin_unlock(&ci->i_ceph_lock);
2766
2767	if (queue_trunc) {
2768		ceph_queue_vmtruncate(inode);
2769		ceph_fscache_invalidate(inode);
2770	}
2771}
2772
2773/*
2774 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
2775 * different one.  If we are the most recent migration we've seen (as
2776 * indicated by mseq), make note of the migrating cap bits for the
2777 * duration (until we see the corresponding IMPORT).
2778 *
2779 * caller holds s_mutex
2780 */
2781static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
2782			      struct ceph_mds_cap_peer *ph,
2783			      struct ceph_mds_session *session)
2784{
2785	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2786	struct ceph_mds_session *tsession = NULL;
2787	struct ceph_cap *cap, *tcap;
2788	struct ceph_inode_info *ci = ceph_inode(inode);
2789	u64 t_cap_id;
2790	unsigned mseq = le32_to_cpu(ex->migrate_seq);
2791	unsigned t_seq, t_mseq;
2792	int target, issued;
2793	int mds = session->s_mds;
2794
2795	if (ph) {
2796		t_cap_id = le64_to_cpu(ph->cap_id);
2797		t_seq = le32_to_cpu(ph->seq);
2798		t_mseq = le32_to_cpu(ph->mseq);
2799		target = le32_to_cpu(ph->mds);
2800	} else {
2801		t_cap_id = t_seq = t_mseq = 0;
2802		target = -1;
2803	}
2804
2805	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
2806	     inode, ci, mds, mseq, target);
2807retry:
 
2808	spin_lock(&ci->i_ceph_lock);
2809	cap = __get_cap_for_mds(ci, mds);
2810	if (!cap)
2811		goto out_unlock;
2812
2813	if (target < 0) {
2814		__ceph_remove_cap(cap, false);
2815		goto out_unlock;
2816	}
2817
2818	/*
2819	 * now we know we haven't received the cap import message yet
2820	 * because the exported cap still exist.
2821	 */
2822
2823	issued = cap->issued;
2824	WARN_ON(issued != cap->implemented);
 
 
 
 
 
 
 
2825
2826	tcap = __get_cap_for_mds(ci, target);
2827	if (tcap) {
2828		/* already have caps from the target */
2829		if (tcap->cap_id != t_cap_id ||
2830		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
2831			dout(" updating import cap %p mds%d\n", tcap, target);
2832			tcap->cap_id = t_cap_id;
2833			tcap->seq = t_seq - 1;
2834			tcap->issue_seq = t_seq - 1;
2835			tcap->mseq = t_mseq;
2836			tcap->issued |= issued;
2837			tcap->implemented |= issued;
2838			if (cap == ci->i_auth_cap)
2839				ci->i_auth_cap = tcap;
2840			if (ci->i_flushing_caps && ci->i_auth_cap == tcap) {
2841				spin_lock(&mdsc->cap_dirty_lock);
2842				list_move_tail(&ci->i_flushing_item,
2843					       &tcap->session->s_cap_flushing);
2844				spin_unlock(&mdsc->cap_dirty_lock);
2845			}
2846		}
2847		__ceph_remove_cap(cap, false);
2848		goto out_unlock;
2849	}
2850
2851	if (tsession) {
2852		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
2853		spin_unlock(&ci->i_ceph_lock);
2854		/* add placeholder for the export tagert */
2855		ceph_add_cap(inode, tsession, t_cap_id, -1, issued, 0,
2856			     t_seq - 1, t_mseq, (u64)-1, flag, NULL);
2857		goto retry;
 
 
 
 
 
 
 
 
 
 
 
 
2858	}
2859
2860	spin_unlock(&ci->i_ceph_lock);
 
2861	mutex_unlock(&session->s_mutex);
2862
2863	/* open target session */
2864	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
2865	if (!IS_ERR(tsession)) {
2866		if (mds > target) {
2867			mutex_lock(&session->s_mutex);
2868			mutex_lock_nested(&tsession->s_mutex,
2869					  SINGLE_DEPTH_NESTING);
2870		} else {
2871			mutex_lock(&tsession->s_mutex);
2872			mutex_lock_nested(&session->s_mutex,
2873					  SINGLE_DEPTH_NESTING);
2874		}
2875		ceph_add_cap_releases(mdsc, tsession);
2876	} else {
2877		WARN_ON(1);
2878		tsession = NULL;
2879		target = -1;
 
2880	}
2881	goto retry;
2882
2883out_unlock:
2884	spin_unlock(&ci->i_ceph_lock);
 
2885	mutex_unlock(&session->s_mutex);
2886	if (tsession) {
2887		mutex_unlock(&tsession->s_mutex);
2888		ceph_put_mds_session(tsession);
2889	}
 
 
2890}
2891
2892/*
2893 * Handle cap IMPORT.  If there are temp bits from an older EXPORT,
2894 * clean them up.
2895 *
2896 * caller holds s_mutex.
2897 */
2898static void handle_cap_import(struct ceph_mds_client *mdsc,
2899			      struct inode *inode, struct ceph_mds_caps *im,
2900			      struct ceph_mds_cap_peer *ph,
2901			      struct ceph_mds_session *session,
2902			      void *snaptrace, int snaptrace_len)
2903{
2904	struct ceph_inode_info *ci = ceph_inode(inode);
2905	struct ceph_cap *cap;
2906	int mds = session->s_mds;
2907	unsigned issued = le32_to_cpu(im->caps);
 
2908	unsigned wanted = le32_to_cpu(im->wanted);
2909	unsigned seq = le32_to_cpu(im->seq);
2910	unsigned mseq = le32_to_cpu(im->migrate_seq);
2911	u64 realmino = le64_to_cpu(im->realm);
2912	u64 cap_id = le64_to_cpu(im->cap_id);
2913	u64 p_cap_id;
2914	int peer;
2915
2916	if (ph) {
2917		p_cap_id = le64_to_cpu(ph->cap_id);
2918		peer = le32_to_cpu(ph->mds);
2919	} else {
2920		p_cap_id = 0;
2921		peer = -1;
2922	}
2923
2924	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
2925	     inode, ci, mds, mseq, peer);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2926
2927	spin_lock(&ci->i_ceph_lock);
2928	cap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
2929	if (cap && cap->cap_id == p_cap_id) {
 
 
 
 
 
2930		dout(" remove export cap %p mds%d flags %d\n",
2931		     cap, peer, ph->flags);
2932		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
2933		    (cap->seq != le32_to_cpu(ph->seq) ||
2934		     cap->mseq != le32_to_cpu(ph->mseq))) {
2935			pr_err("handle_cap_import: mismatched seq/mseq: "
2936			       "ino (%llx.%llx) mds%d seq %d mseq %d "
2937			       "importer mds%d has peer seq %d mseq %d\n",
2938			       ceph_vinop(inode), peer, cap->seq,
2939			       cap->mseq, mds, le32_to_cpu(ph->seq),
2940			       le32_to_cpu(ph->mseq));
2941		}
2942		ci->i_cap_exporting_issued = cap->issued;
2943		__ceph_remove_cap(cap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
2944	}
2945
2946	/* make sure we re-request max_size, if necessary */
2947	ci->i_wanted_max_size = 0;
2948	ci->i_requested_max_size = 0;
2949	spin_unlock(&ci->i_ceph_lock);
2950
2951	down_write(&mdsc->snap_rwsem);
2952	ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
2953			       false);
2954	downgrade_write(&mdsc->snap_rwsem);
2955	ceph_add_cap(inode, session, cap_id, -1,
2956		     issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
2957		     NULL /* no caps context */);
2958	kick_flushing_inode_caps(mdsc, session, inode);
2959	up_read(&mdsc->snap_rwsem);
2960
 
 
2961}
2962
2963/*
2964 * Handle a caps message from the MDS.
2965 *
2966 * Identify the appropriate session, inode, and call the right handler
2967 * based on the cap op.
2968 */
2969void ceph_handle_caps(struct ceph_mds_session *session,
2970		      struct ceph_msg *msg)
2971{
2972	struct ceph_mds_client *mdsc = session->s_mdsc;
2973	struct super_block *sb = mdsc->fsc->sb;
2974	struct inode *inode;
2975	struct ceph_inode_info *ci;
2976	struct ceph_cap *cap;
2977	struct ceph_mds_caps *h;
2978	struct ceph_mds_cap_peer *peer = NULL;
2979	int mds = session->s_mds;
2980	int op;
 
2981	u32 seq, mseq;
2982	struct ceph_vino vino;
2983	u64 cap_id;
2984	u64 size, max_size;
2985	u64 tid;
2986	void *snaptrace;
2987	size_t snaptrace_len;
2988	void *flock;
2989	void *end;
2990	u32 flock_len;
 
2991
2992	dout("handle_caps from mds%d\n", mds);
2993
2994	/* decode */
2995	end = msg->front.iov_base + msg->front.iov_len;
2996	tid = le64_to_cpu(msg->hdr.tid);
2997	if (msg->front.iov_len < sizeof(*h))
2998		goto bad;
2999	h = msg->front.iov_base;
3000	op = le32_to_cpu(h->op);
3001	vino.ino = le64_to_cpu(h->ino);
3002	vino.snap = CEPH_NOSNAP;
3003	cap_id = le64_to_cpu(h->cap_id);
3004	seq = le32_to_cpu(h->seq);
3005	mseq = le32_to_cpu(h->migrate_seq);
3006	size = le64_to_cpu(h->size);
3007	max_size = le64_to_cpu(h->max_size);
3008
3009	snaptrace = h + 1;
3010	snaptrace_len = le32_to_cpu(h->snap_trace_len);
 
3011
3012	if (le16_to_cpu(msg->hdr.version) >= 2) {
3013		void *p = snaptrace + snaptrace_len;
3014		ceph_decode_32_safe(&p, end, flock_len, bad);
3015		if (p + flock_len > end)
3016			goto bad;
3017		flock = p;
3018	} else {
3019		flock = NULL;
3020		flock_len = 0;
3021	}
3022
3023	if (le16_to_cpu(msg->hdr.version) >= 3) {
3024		if (op == CEPH_CAP_OP_IMPORT) {
3025			void *p = flock + flock_len;
3026			if (p + sizeof(*peer) > end)
3027				goto bad;
3028			peer = p;
 
3029		} else if (op == CEPH_CAP_OP_EXPORT) {
3030			/* recorded in unused fields */
3031			peer = (void *)&h->size;
3032		}
3033	}
3034
3035	mutex_lock(&session->s_mutex);
3036	session->s_seq++;
3037	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
3038	     (unsigned)seq);
 
 
 
 
3039
3040	if (op == CEPH_CAP_OP_IMPORT)
3041		ceph_add_cap_releases(mdsc, session);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3042
3043	/* lookup ino */
3044	inode = ceph_find_inode(sb, vino);
3045	ci = ceph_inode(inode);
3046	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
3047	     vino.snap, inode);
 
 
 
 
 
 
3048	if (!inode) {
3049		dout(" i don't have ino %llx\n", vino.ino);
3050
3051		if (op == CEPH_CAP_OP_IMPORT) {
 
 
 
 
 
 
 
3052			spin_lock(&session->s_cap_lock);
3053			__queue_cap_release(session, vino.ino, cap_id,
3054					    mseq, seq);
3055			spin_unlock(&session->s_cap_lock);
3056		}
3057		goto flush_cap_releases;
3058	}
 
3059
3060	/* these will work even if we don't have a cap yet */
3061	switch (op) {
3062	case CEPH_CAP_OP_FLUSHSNAP_ACK:
3063		handle_cap_flushsnap_ack(inode, tid, h, session);
 
3064		goto done;
3065
3066	case CEPH_CAP_OP_EXPORT:
3067		handle_cap_export(inode, h, peer, session);
3068		goto done_unlocked;
3069
3070	case CEPH_CAP_OP_IMPORT:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3071		handle_cap_import(mdsc, inode, h, peer, session,
3072				  snaptrace, snaptrace_len);
 
 
 
 
 
3073	}
3074
3075	/* the rest require a cap */
3076	spin_lock(&ci->i_ceph_lock);
3077	cap = __get_cap_for_mds(ceph_inode(inode), mds);
3078	if (!cap) {
3079		dout(" no cap on %p ino %llx.%llx from mds%d\n",
3080		     inode, ceph_ino(inode), ceph_snap(inode), mds);
 
3081		spin_unlock(&ci->i_ceph_lock);
3082		goto flush_cap_releases;
3083	}
3084
3085	/* note that each of these drops i_ceph_lock for us */
3086	switch (op) {
3087	case CEPH_CAP_OP_REVOKE:
3088	case CEPH_CAP_OP_GRANT:
3089	case CEPH_CAP_OP_IMPORT:
3090		handle_cap_grant(inode, h, session, cap, msg->middle);
 
 
3091		goto done_unlocked;
3092
3093	case CEPH_CAP_OP_FLUSH_ACK:
3094		handle_cap_flush_ack(inode, tid, h, session, cap);
 
3095		break;
3096
3097	case CEPH_CAP_OP_TRUNC:
3098		handle_cap_trunc(inode, h, session);
 
 
 
3099		break;
3100
3101	default:
3102		spin_unlock(&ci->i_ceph_lock);
3103		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
3104		       ceph_cap_op_name(op));
3105	}
3106
3107	goto done;
 
 
 
 
 
 
 
 
 
 
 
3108
3109flush_cap_releases:
3110	/*
3111	 * send any full release message to try to move things
3112	 * along for the mds (who clearly thinks we still have this
3113	 * cap).
3114	 */
3115	ceph_add_cap_releases(mdsc, session);
3116	ceph_send_cap_releases(mdsc, session);
3117
3118done:
3119	mutex_unlock(&session->s_mutex);
3120done_unlocked:
3121	if (inode)
3122		iput(inode);
3123	return;
3124
3125bad:
3126	pr_err("ceph_handle_caps: corrupt message\n");
3127	ceph_msg_dump(msg);
3128	return;
3129}
3130
3131/*
3132 * Delayed work handler to process end of delayed cap release LRU list.
 
 
 
 
3133 */
3134void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
3135{
 
3136	struct ceph_inode_info *ci;
3137	int flags = CHECK_CAPS_NODELAY;
 
 
 
3138
3139	dout("check_delayed_caps\n");
3140	while (1) {
3141		spin_lock(&mdsc->cap_delay_lock);
3142		if (list_empty(&mdsc->cap_delay_list))
3143			break;
3144		ci = list_first_entry(&mdsc->cap_delay_list,
3145				      struct ceph_inode_info,
3146				      i_cap_delay_list);
 
 
 
 
 
3147		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
3148		    time_before(jiffies, ci->i_hold_caps_max))
3149			break;
3150		list_del_init(&ci->i_cap_delay_list);
3151		spin_unlock(&mdsc->cap_delay_lock);
3152		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
3153		ceph_check_caps(ci, flags, NULL);
 
 
 
 
 
 
3154	}
3155	spin_unlock(&mdsc->cap_delay_lock);
 
 
3156}
3157
3158/*
3159 * Flush all dirty caps to the mds
3160 */
3161void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
3162{
 
3163	struct ceph_inode_info *ci;
3164	struct inode *inode;
3165
3166	dout("flush_dirty_caps\n");
3167	spin_lock(&mdsc->cap_dirty_lock);
3168	while (!list_empty(&mdsc->cap_dirty)) {
3169		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
3170				      i_dirty_item);
3171		inode = &ci->vfs_inode;
3172		ihold(inode);
3173		dout("flush_dirty_caps %p\n", inode);
3174		spin_unlock(&mdsc->cap_dirty_lock);
3175		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
 
3176		iput(inode);
3177		spin_lock(&mdsc->cap_dirty_lock);
3178	}
3179	spin_unlock(&mdsc->cap_dirty_lock);
3180	dout("flush_dirty_caps done\n");
3181}
3182
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3183/*
3184 * Drop open file reference.  If we were the last open file,
3185 * we may need to release capabilities to the MDS (or schedule
3186 * their delayed release).
3187 */
3188void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
3189{
3190	struct inode *inode = &ci->vfs_inode;
3191	int last = 0;
 
 
 
 
 
3192
3193	spin_lock(&ci->i_ceph_lock);
3194	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
3195	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
3196	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
3197	if (--ci->i_nr_by_mode[fmode] == 0)
3198		last++;
 
 
 
 
 
 
 
 
 
 
 
 
3199	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3200
3201	if (last && ci->i_vino.snap == CEPH_NOSNAP)
3202		ceph_check_caps(ci, 0, NULL);
 
 
 
 
 
 
3203}
3204
3205/*
3206 * Helpers for embedding cap and dentry lease releases into mds
3207 * requests.
3208 *
3209 * @force is used by dentry_release (below) to force inclusion of a
3210 * record for the directory inode, even when there aren't any caps to
3211 * drop.
3212 */
3213int ceph_encode_inode_release(void **p, struct inode *inode,
3214			      int mds, int drop, int unless, int force)
3215{
3216	struct ceph_inode_info *ci = ceph_inode(inode);
3217	struct ceph_cap *cap;
3218	struct ceph_mds_request_release *rel = *p;
3219	int used, dirty;
3220	int ret = 0;
3221
3222	spin_lock(&ci->i_ceph_lock);
3223	used = __ceph_caps_used(ci);
3224	dirty = __ceph_caps_dirty(ci);
3225
3226	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
3227	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3228	     ceph_cap_string(unless));
3229
3230	/* only drop unused, clean caps */
3231	drop &= ~(used | dirty);
3232
3233	cap = __get_cap_for_mds(ci, mds);
3234	if (cap && __cap_is_valid(cap)) {
3235		if (force ||
3236		    ((cap->issued & drop) &&
3237		     (cap->issued & unless) == 0)) {
3238			if ((cap->issued & drop) &&
3239			    (cap->issued & unless) == 0) {
 
 
 
 
 
 
 
 
 
3240				int wanted = __ceph_caps_wanted(ci);
3241				if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0)
3242					wanted |= cap->mds_wanted;
3243				dout("encode_inode_release %p cap %p "
3244				     "%s -> %s, wanted %s -> %s\n", inode, cap,
3245				     ceph_cap_string(cap->issued),
3246				     ceph_cap_string(cap->issued & ~drop),
3247				     ceph_cap_string(cap->mds_wanted),
3248				     ceph_cap_string(wanted));
3249
3250				cap->issued &= ~drop;
3251				cap->implemented &= ~drop;
3252				cap->mds_wanted = wanted;
 
 
 
3253			} else {
3254				dout("encode_inode_release %p cap %p %s"
3255				     " (force)\n", inode, cap,
3256				     ceph_cap_string(cap->issued));
3257			}
3258
3259			rel->ino = cpu_to_le64(ceph_ino(inode));
3260			rel->cap_id = cpu_to_le64(cap->cap_id);
3261			rel->seq = cpu_to_le32(cap->seq);
3262			rel->issue_seq = cpu_to_le32(cap->issue_seq),
3263			rel->mseq = cpu_to_le32(cap->mseq);
3264			rel->caps = cpu_to_le32(cap->implemented);
3265			rel->wanted = cpu_to_le32(cap->mds_wanted);
3266			rel->dname_len = 0;
3267			rel->dname_seq = 0;
3268			*p += sizeof(*rel);
3269			ret = 1;
3270		} else {
3271			dout("encode_inode_release %p cap %p %s\n",
3272			     inode, cap, ceph_cap_string(cap->issued));
3273		}
3274	}
3275	spin_unlock(&ci->i_ceph_lock);
3276	return ret;
3277}
3278
3279int ceph_encode_dentry_release(void **p, struct dentry *dentry,
 
3280			       int mds, int drop, int unless)
3281{
3282	struct inode *dir = dentry->d_parent->d_inode;
3283	struct ceph_mds_request_release *rel = *p;
3284	struct ceph_dentry_info *di = ceph_dentry(dentry);
3285	int force = 0;
3286	int ret;
3287
3288	/*
3289	 * force an record for the directory caps if we have a dentry lease.
3290	 * this is racy (can't take i_ceph_lock and d_lock together), but it
3291	 * doesn't have to be perfect; the mds will revoke anything we don't
3292	 * release.
3293	 */
3294	spin_lock(&dentry->d_lock);
3295	if (di->lease_session && di->lease_session->s_mds == mds)
3296		force = 1;
 
 
 
 
3297	spin_unlock(&dentry->d_lock);
3298
3299	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
 
3300
3301	spin_lock(&dentry->d_lock);
3302	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
3303		dout("encode_dentry_release %p mds%d seq %d\n",
3304		     dentry, mds, (int)di->lease_seq);
3305		rel->dname_len = cpu_to_le32(dentry->d_name.len);
3306		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
3307		*p += dentry->d_name.len;
3308		rel->dname_seq = cpu_to_le32(di->lease_seq);
3309		__ceph_mdsc_drop_dentry_lease(dentry);
3310	}
3311	spin_unlock(&dentry->d_lock);
3312	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3313}
v6.2
   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	ci->i_hold_caps_max = round_jiffies(jiffies +
 494					    opt->caps_wanted_delay_max * HZ);
 495	dout("__cap_set_timeouts %p %lu\n", &ci->netfs.inode,
 496	     ci->i_hold_caps_max - jiffies);
 497}
 498
 499/*
 500 * (Re)queue cap at the end of the delayed cap release list.
 501 *
 502 * If I_FLUSH is set, leave the inode at the front of the list.
 503 *
 504 * Caller holds i_ceph_lock
 505 *    -> we take mdsc->cap_delay_lock
 506 */
 507static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 508				struct ceph_inode_info *ci)
 509{
 510	dout("__cap_delay_requeue %p flags 0x%lx at %lu\n", &ci->netfs.inode,
 
 511	     ci->i_ceph_flags, ci->i_hold_caps_max);
 512	if (!mdsc->stopping) {
 513		spin_lock(&mdsc->cap_delay_lock);
 514		if (!list_empty(&ci->i_cap_delay_list)) {
 515			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 516				goto no_change;
 517			list_del_init(&ci->i_cap_delay_list);
 518		}
 519		__cap_set_timeouts(mdsc, ci);
 520		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 521no_change:
 522		spin_unlock(&mdsc->cap_delay_lock);
 523	}
 524}
 525
 526/*
 527 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 528 * indicating we should send a cap message to flush dirty metadata
 529 * asap, and move to the front of the delayed cap list.
 530 */
 531static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 532				      struct ceph_inode_info *ci)
 533{
 534	dout("__cap_delay_requeue_front %p\n", &ci->netfs.inode);
 535	spin_lock(&mdsc->cap_delay_lock);
 536	ci->i_ceph_flags |= CEPH_I_FLUSH;
 537	if (!list_empty(&ci->i_cap_delay_list))
 538		list_del_init(&ci->i_cap_delay_list);
 539	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 540	spin_unlock(&mdsc->cap_delay_lock);
 541}
 542
 543/*
 544 * Cancel delayed work on cap.
 545 *
 546 * Caller must hold i_ceph_lock.
 547 */
 548static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 549			       struct ceph_inode_info *ci)
 550{
 551	dout("__cap_delay_cancel %p\n", &ci->netfs.inode);
 552	if (list_empty(&ci->i_cap_delay_list))
 553		return;
 554	spin_lock(&mdsc->cap_delay_lock);
 555	list_del_init(&ci->i_cap_delay_list);
 556	spin_unlock(&mdsc->cap_delay_lock);
 557}
 558
 559/* Common issue checks for add_cap, handle_cap_grant. */
 
 
 560static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 561			      unsigned issued)
 562{
 563	unsigned had = __ceph_caps_issued(ci, NULL);
 564
 565	lockdep_assert_held(&ci->i_ceph_lock);
 566
 567	/*
 568	 * Each time we receive FILE_CACHE anew, we increment
 569	 * i_rdcache_gen.
 570	 */
 571	if (S_ISREG(ci->netfs.inode.i_mode) &&
 572	    (issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 573	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) {
 574		ci->i_rdcache_gen++;
 575	}
 576
 577	/*
 578	 * If FILE_SHARED is newly issued, mark dir not complete. We don't
 579	 * know what happened to this directory while we didn't have the cap.
 580	 * If FILE_SHARED is being revoked, also mark dir not complete. It
 581	 * stops on-going cached readdir.
 582	 */
 583	if ((issued & CEPH_CAP_FILE_SHARED) != (had & CEPH_CAP_FILE_SHARED)) {
 584		if (issued & CEPH_CAP_FILE_SHARED)
 585			atomic_inc(&ci->i_shared_gen);
 586		if (S_ISDIR(ci->netfs.inode.i_mode)) {
 587			dout(" marking %p NOT complete\n", &ci->netfs.inode);
 588			__ceph_dir_clear_complete(ci);
 589		}
 590	}
 591
 592	/* Wipe saved layout if we're losing DIR_CREATE caps */
 593	if (S_ISDIR(ci->netfs.inode.i_mode) && (had & CEPH_CAP_DIR_CREATE) &&
 594		!(issued & CEPH_CAP_DIR_CREATE)) {
 595	     ceph_put_string(rcu_dereference_raw(ci->i_cached_layout.pool_ns));
 596	     memset(&ci->i_cached_layout, 0, sizeof(ci->i_cached_layout));
 597	}
 598}
 599
 600/**
 601 * change_auth_cap_ses - move inode to appropriate lists when auth caps change
 602 * @ci: inode to be moved
 603 * @session: new auth caps session
 604 */
 605void change_auth_cap_ses(struct ceph_inode_info *ci,
 606			 struct ceph_mds_session *session)
 607{
 608	lockdep_assert_held(&ci->i_ceph_lock);
 609
 610	if (list_empty(&ci->i_dirty_item) && list_empty(&ci->i_flushing_item))
 611		return;
 612
 613	spin_lock(&session->s_mdsc->cap_dirty_lock);
 614	if (!list_empty(&ci->i_dirty_item))
 615		list_move(&ci->i_dirty_item, &session->s_cap_dirty);
 616	if (!list_empty(&ci->i_flushing_item))
 617		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
 618	spin_unlock(&session->s_mdsc->cap_dirty_lock);
 619}
 620
 621/*
 622 * Add a capability under the given MDS session.
 623 *
 624 * Caller should hold session snap_rwsem (read) and ci->i_ceph_lock
 625 *
 626 * @fmode is the open file mode, if we are opening a file, otherwise
 627 * it is < 0.  (This is so we can atomically add the cap and add an
 628 * open file reference to it.)
 629 */
 630void ceph_add_cap(struct inode *inode,
 631		  struct ceph_mds_session *session, u64 cap_id,
 632		  unsigned issued, unsigned wanted,
 633		  unsigned seq, unsigned mseq, u64 realmino, int flags,
 634		  struct ceph_cap **new_cap)
 635{
 636	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 637	struct ceph_inode_info *ci = ceph_inode(inode);
 
 638	struct ceph_cap *cap;
 639	int mds = session->s_mds;
 640	int actual_wanted;
 641	u32 gen;
 642
 643	lockdep_assert_held(&ci->i_ceph_lock);
 644
 645	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 646	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 647
 648	gen = atomic_read(&session->s_cap_gen);
 
 
 
 
 
 649
 
 
 650	cap = __get_cap_for_mds(ci, mds);
 651	if (!cap) {
 652		cap = *new_cap;
 653		*new_cap = NULL;
 
 
 
 
 
 
 
 
 654
 655		cap->issued = 0;
 656		cap->implemented = 0;
 657		cap->mds = mds;
 658		cap->mds_wanted = 0;
 659		cap->mseq = 0;
 660
 661		cap->ci = ci;
 662		__insert_cap_node(ci, cap);
 663
 664		/* add to session cap list */
 665		cap->session = session;
 666		spin_lock(&session->s_cap_lock);
 667		list_add_tail(&cap->session_caps, &session->s_caps);
 668		session->s_nr_caps++;
 669		atomic64_inc(&mdsc->metric.total_caps);
 670		spin_unlock(&session->s_cap_lock);
 671	} else {
 672		spin_lock(&session->s_cap_lock);
 673		list_move_tail(&cap->session_caps, &session->s_caps);
 674		spin_unlock(&session->s_cap_lock);
 675
 676		if (cap->cap_gen < gen)
 677			cap->issued = cap->implemented = CEPH_CAP_PIN;
 678
 679		/*
 680		 * auth mds of the inode changed. we received the cap export
 681		 * message, but still haven't received the cap import message.
 682		 * handle_cap_export() updated the new auth MDS' cap.
 683		 *
 684		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 685		 * a message that was send before the cap import message. So
 686		 * don't remove caps.
 687		 */
 688		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 689			WARN_ON(cap != ci->i_auth_cap);
 690			WARN_ON(cap->cap_id != cap_id);
 691			seq = cap->seq;
 692			mseq = cap->mseq;
 693			issued |= cap->issued;
 694			flags |= CEPH_CAP_FLAG_AUTH;
 695		}
 696	}
 697
 698	if (!ci->i_snap_realm ||
 699	    ((flags & CEPH_CAP_FLAG_AUTH) &&
 700	     realmino != (u64)-1 && ci->i_snap_realm->ino != realmino)) {
 701		/*
 702		 * add this inode to the appropriate snap realm
 703		 */
 704		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 705							       realmino);
 706		if (realm)
 707			ceph_change_snap_realm(inode, realm);
 708		else
 709			WARN(1, "%s: couldn't find snap realm 0x%llx (ino 0x%llx oldrealm 0x%llx)\n",
 710			     __func__, realmino, ci->i_vino.ino,
 711			     ci->i_snap_realm ? ci->i_snap_realm->ino : 0);
 
 
 
 
 
 
 712	}
 713
 714	__check_cap_issue(ci, cap, issued);
 715
 716	/*
 717	 * If we are issued caps we don't want, or the mds' wanted
 718	 * value appears to be off, queue a check so we'll release
 719	 * later and/or update the mds wanted value.
 720	 */
 721	actual_wanted = __ceph_caps_wanted(ci);
 722	if ((wanted & ~actual_wanted) ||
 723	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 724		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 725		     ceph_cap_string(issued), ceph_cap_string(wanted),
 726		     ceph_cap_string(actual_wanted));
 727		__cap_delay_requeue(mdsc, ci);
 728	}
 729
 730	if (flags & CEPH_CAP_FLAG_AUTH) {
 731		if (!ci->i_auth_cap ||
 732		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 733			if (ci->i_auth_cap &&
 734			    ci->i_auth_cap->session != cap->session)
 735				change_auth_cap_ses(ci, cap->session);
 736			ci->i_auth_cap = cap;
 737			cap->mds_wanted = wanted;
 738		}
 
 739	} else {
 740		WARN_ON(ci->i_auth_cap == cap);
 741	}
 742
 743	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 744	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 745	     ceph_cap_string(issued|cap->issued), seq, mds);
 746	cap->cap_id = cap_id;
 747	cap->issued = issued;
 748	cap->implemented |= issued;
 749	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 750		cap->mds_wanted = wanted;
 751	else
 752		cap->mds_wanted |= wanted;
 753	cap->seq = seq;
 754	cap->issue_seq = seq;
 755	cap->mseq = mseq;
 756	cap->cap_gen = gen;
 
 
 
 
 757	wake_up_all(&ci->i_cap_wq);
 
 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	gen = atomic_read(&cap->session->s_cap_gen);
 
 771	ttl = cap->session->s_cap_ttl;
 
 772
 773	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 774		dout("__cap_is_valid %p cap %p issued %s "
 775		     "but STALE (gen %u vs %u)\n", &cap->ci->netfs.inode,
 776		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 777		return 0;
 778	}
 779
 780	return 1;
 781}
 782
 783/*
 784 * Return set of valid cap bits issued to us.  Note that caps time
 785 * out, and may be invalidated in bulk if the client session times out
 786 * and session->s_cap_gen is bumped.
 787 */
 788int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 789{
 790	int have = ci->i_snap_caps;
 791	struct ceph_cap *cap;
 792	struct rb_node *p;
 793
 794	if (implemented)
 795		*implemented = 0;
 796	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 797		cap = rb_entry(p, struct ceph_cap, ci_node);
 798		if (!__cap_is_valid(cap))
 799			continue;
 800		dout("__ceph_caps_issued %p cap %p issued %s\n",
 801		     &ci->netfs.inode, cap, ceph_cap_string(cap->issued));
 802		have |= cap->issued;
 803		if (implemented)
 804			*implemented |= cap->implemented;
 805	}
 806	/*
 807	 * exclude caps issued by non-auth MDS, but are been revoking
 808	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 809	 * these caps, but the message is delayed.
 810	 */
 811	if (ci->i_auth_cap) {
 812		cap = ci->i_auth_cap;
 813		have &= ~cap->implemented | cap->issued;
 814	}
 815	return have;
 816}
 817
 818/*
 819 * Get cap bits issued by caps other than @ocap
 820 */
 821int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 822{
 823	int have = ci->i_snap_caps;
 824	struct ceph_cap *cap;
 825	struct rb_node *p;
 826
 827	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 828		cap = rb_entry(p, struct ceph_cap, ci_node);
 829		if (cap == ocap)
 830			continue;
 831		if (!__cap_is_valid(cap))
 832			continue;
 833		have |= cap->issued;
 834	}
 835	return have;
 836}
 837
 838/*
 839 * Move a cap to the end of the LRU (oldest caps at list head, newest
 840 * at list tail).
 841 */
 842static void __touch_cap(struct ceph_cap *cap)
 843{
 844	struct ceph_mds_session *s = cap->session;
 845
 846	spin_lock(&s->s_cap_lock);
 847	if (!s->s_cap_iterator) {
 848		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->netfs.inode, cap,
 849		     s->s_mds);
 850		list_move_tail(&cap->session_caps, &s->s_caps);
 851	} else {
 852		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 853		     &cap->ci->netfs.inode, cap, s->s_mds);
 854	}
 855	spin_unlock(&s->s_cap_lock);
 856}
 857
 858/*
 859 * Check if we hold the given mask.  If so, move the cap(s) to the
 860 * front of their respective LRUs.  (This is the preferred way for
 861 * callers to check for caps they want.)
 862 */
 863int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 864{
 865	struct ceph_cap *cap;
 866	struct rb_node *p;
 867	int have = ci->i_snap_caps;
 868
 869	if ((have & mask) == mask) {
 870		dout("__ceph_caps_issued_mask ino 0x%llx snap issued %s"
 871		     " (mask %s)\n", ceph_ino(&ci->netfs.inode),
 872		     ceph_cap_string(have),
 873		     ceph_cap_string(mask));
 874		return 1;
 875	}
 876
 877	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 878		cap = rb_entry(p, struct ceph_cap, ci_node);
 879		if (!__cap_is_valid(cap))
 880			continue;
 881		if ((cap->issued & mask) == mask) {
 882			dout("__ceph_caps_issued_mask ino 0x%llx cap %p issued %s"
 883			     " (mask %s)\n", ceph_ino(&ci->netfs.inode), cap,
 884			     ceph_cap_string(cap->issued),
 885			     ceph_cap_string(mask));
 886			if (touch)
 887				__touch_cap(cap);
 888			return 1;
 889		}
 890
 891		/* does a combination of caps satisfy mask? */
 892		have |= cap->issued;
 893		if ((have & mask) == mask) {
 894			dout("__ceph_caps_issued_mask ino 0x%llx combo issued %s"
 895			     " (mask %s)\n", ceph_ino(&ci->netfs.inode),
 896			     ceph_cap_string(cap->issued),
 897			     ceph_cap_string(mask));
 898			if (touch) {
 899				struct rb_node *q;
 900
 901				/* touch this + preceding caps */
 902				__touch_cap(cap);
 903				for (q = rb_first(&ci->i_caps); q != p;
 904				     q = rb_next(q)) {
 905					cap = rb_entry(q, struct ceph_cap,
 906						       ci_node);
 907					if (!__cap_is_valid(cap))
 908						continue;
 909					if (cap->issued & mask)
 910						__touch_cap(cap);
 911				}
 912			}
 913			return 1;
 914		}
 915	}
 916
 917	return 0;
 918}
 919
 920int __ceph_caps_issued_mask_metric(struct ceph_inode_info *ci, int mask,
 921				   int touch)
 922{
 923	struct ceph_fs_client *fsc = ceph_sb_to_client(ci->netfs.inode.i_sb);
 924	int r;
 925
 926	r = __ceph_caps_issued_mask(ci, mask, touch);
 927	if (r)
 928		ceph_update_cap_hit(&fsc->mdsc->metric);
 929	else
 930		ceph_update_cap_mis(&fsc->mdsc->metric);
 931	return r;
 932}
 933
 934/*
 935 * Return true if mask caps are currently being revoked by an MDS.
 936 */
 937int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 938			       struct ceph_cap *ocap, int mask)
 939{
 940	struct ceph_cap *cap;
 941	struct rb_node *p;
 942
 943	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 944		cap = rb_entry(p, struct ceph_cap, ci_node);
 945		if (cap != ocap &&
 946		    (cap->implemented & ~cap->issued & mask))
 947			return 1;
 948	}
 949	return 0;
 950}
 951
 952int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 953{
 954	struct inode *inode = &ci->netfs.inode;
 955	int ret;
 956
 957	spin_lock(&ci->i_ceph_lock);
 958	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 959	spin_unlock(&ci->i_ceph_lock);
 960	dout("ceph_caps_revoking %p %s = %d\n", inode,
 961	     ceph_cap_string(mask), ret);
 962	return ret;
 963}
 964
 965int __ceph_caps_used(struct ceph_inode_info *ci)
 966{
 967	int used = 0;
 968	if (ci->i_pin_ref)
 969		used |= CEPH_CAP_PIN;
 970	if (ci->i_rd_ref)
 971		used |= CEPH_CAP_FILE_RD;
 972	if (ci->i_rdcache_ref ||
 973	    (S_ISREG(ci->netfs.inode.i_mode) &&
 974	     ci->netfs.inode.i_data.nrpages))
 975		used |= CEPH_CAP_FILE_CACHE;
 976	if (ci->i_wr_ref)
 977		used |= CEPH_CAP_FILE_WR;
 978	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 979		used |= CEPH_CAP_FILE_BUFFER;
 980	if (ci->i_fx_ref)
 981		used |= CEPH_CAP_FILE_EXCL;
 982	return used;
 983}
 984
 985#define FMODE_WAIT_BIAS 1000
 986
 987/*
 988 * wanted, by virtue of open file modes
 989 */
 990int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 991{
 992	const int PIN_SHIFT = ffs(CEPH_FILE_MODE_PIN);
 993	const int RD_SHIFT = ffs(CEPH_FILE_MODE_RD);
 994	const int WR_SHIFT = ffs(CEPH_FILE_MODE_WR);
 995	const int LAZY_SHIFT = ffs(CEPH_FILE_MODE_LAZY);
 996	struct ceph_mount_options *opt =
 997		ceph_inode_to_client(&ci->netfs.inode)->mount_options;
 998	unsigned long used_cutoff = jiffies - opt->caps_wanted_delay_max * HZ;
 999	unsigned long idle_cutoff = jiffies - opt->caps_wanted_delay_min * HZ;
1000
1001	if (S_ISDIR(ci->netfs.inode.i_mode)) {
1002		int want = 0;
1003
1004		/* use used_cutoff here, to keep dir's wanted caps longer */
1005		if (ci->i_nr_by_mode[RD_SHIFT] > 0 ||
1006		    time_after(ci->i_last_rd, used_cutoff))
1007			want |= CEPH_CAP_ANY_SHARED;
1008
1009		if (ci->i_nr_by_mode[WR_SHIFT] > 0 ||
1010		    time_after(ci->i_last_wr, used_cutoff)) {
1011			want |= CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
1012			if (opt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1013				want |= CEPH_CAP_ANY_DIR_OPS;
1014		}
1015
1016		if (want || ci->i_nr_by_mode[PIN_SHIFT] > 0)
1017			want |= CEPH_CAP_PIN;
1018
1019		return want;
1020	} else {
1021		int bits = 0;
1022
1023		if (ci->i_nr_by_mode[RD_SHIFT] > 0) {
1024			if (ci->i_nr_by_mode[RD_SHIFT] >= FMODE_WAIT_BIAS ||
1025			    time_after(ci->i_last_rd, used_cutoff))
1026				bits |= 1 << RD_SHIFT;
1027		} else if (time_after(ci->i_last_rd, idle_cutoff)) {
1028			bits |= 1 << RD_SHIFT;
1029		}
1030
1031		if (ci->i_nr_by_mode[WR_SHIFT] > 0) {
1032			if (ci->i_nr_by_mode[WR_SHIFT] >= FMODE_WAIT_BIAS ||
1033			    time_after(ci->i_last_wr, used_cutoff))
1034				bits |= 1 << WR_SHIFT;
1035		} else if (time_after(ci->i_last_wr, idle_cutoff)) {
1036			bits |= 1 << WR_SHIFT;
1037		}
1038
1039		/* check lazyio only when read/write is wanted */
1040		if ((bits & (CEPH_FILE_MODE_RDWR << 1)) &&
1041		    ci->i_nr_by_mode[LAZY_SHIFT] > 0)
1042			bits |= 1 << LAZY_SHIFT;
1043
1044		return bits ? ceph_caps_for_mode(bits >> 1) : 0;
1045	}
1046}
1047
1048/*
1049 * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
1050 */
1051int __ceph_caps_wanted(struct ceph_inode_info *ci)
1052{
1053	int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
1054	if (S_ISDIR(ci->netfs.inode.i_mode)) {
1055		/* we want EXCL if holding caps of dir ops */
1056		if (w & CEPH_CAP_ANY_DIR_OPS)
1057			w |= CEPH_CAP_FILE_EXCL;
1058	} else {
1059		/* we want EXCL if dirty data */
1060		if (w & CEPH_CAP_FILE_BUFFER)
1061			w |= CEPH_CAP_FILE_EXCL;
1062	}
1063	return w;
1064}
1065
1066/*
1067 * Return caps we have registered with the MDS(s) as 'wanted'.
1068 */
1069int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check)
1070{
1071	struct ceph_cap *cap;
1072	struct rb_node *p;
1073	int mds_wanted = 0;
1074
1075	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1076		cap = rb_entry(p, struct ceph_cap, ci_node);
1077		if (check && !__cap_is_valid(cap))
1078			continue;
1079		if (cap == ci->i_auth_cap)
1080			mds_wanted |= cap->mds_wanted;
1081		else
1082			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
1083	}
1084	return mds_wanted;
1085}
1086
 
 
 
 
 
 
 
 
1087int ceph_is_any_caps(struct inode *inode)
1088{
1089	struct ceph_inode_info *ci = ceph_inode(inode);
1090	int ret;
1091
1092	spin_lock(&ci->i_ceph_lock);
1093	ret = __ceph_is_any_real_caps(ci);
1094	spin_unlock(&ci->i_ceph_lock);
1095
1096	return ret;
1097}
1098
1099/*
1100 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
1101 *
1102 * caller should hold i_ceph_lock.
1103 * caller will not hold session s_mutex if called from destroy_inode.
1104 */
1105void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
1106{
1107	struct ceph_mds_session *session = cap->session;
1108	struct ceph_inode_info *ci = cap->ci;
1109	struct ceph_mds_client *mdsc;
 
1110	int removed = 0;
1111
1112	/* 'ci' being NULL means the remove have already occurred */
1113	if (!ci) {
1114		dout("%s: cap inode is NULL\n", __func__);
1115		return;
1116	}
1117
1118	lockdep_assert_held(&ci->i_ceph_lock);
1119
1120	dout("__ceph_remove_cap %p from %p\n", cap, &ci->netfs.inode);
1121
1122	mdsc = ceph_inode_to_client(&ci->netfs.inode)->mdsc;
1123
1124	/* remove from inode's cap rbtree, and clear auth cap */
1125	rb_erase(&cap->ci_node, &ci->i_caps);
1126	if (ci->i_auth_cap == cap)
1127		ci->i_auth_cap = NULL;
1128
1129	/* remove from session list */
1130	spin_lock(&session->s_cap_lock);
 
 
 
 
 
 
 
 
 
 
1131	if (session->s_cap_iterator == cap) {
1132		/* not yet, we are iterating over this very cap */
1133		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
1134		     cap, cap->session);
1135	} else {
1136		list_del_init(&cap->session_caps);
1137		session->s_nr_caps--;
1138		atomic64_dec(&mdsc->metric.total_caps);
1139		cap->session = NULL;
1140		removed = 1;
1141	}
1142	/* protect backpointer with s_cap_lock: see iterate_session_caps */
1143	cap->ci = NULL;
 
1144
1145	/*
1146	 * s_cap_reconnect is protected by s_cap_lock. no one changes
1147	 * s_cap_gen while session is in the reconnect state.
1148	 */
1149	if (queue_release &&
1150	    (!session->s_cap_reconnect ||
1151	     cap->cap_gen == atomic_read(&session->s_cap_gen))) {
1152		cap->queue_release = 1;
1153		if (removed) {
1154			__ceph_queue_cap_release(session, cap);
1155			removed = 0;
1156		}
1157	} else {
1158		cap->queue_release = 0;
1159	}
1160	cap->cap_ino = ci->i_vino.ino;
1161
1162	spin_unlock(&session->s_cap_lock);
1163
1164	if (removed)
1165		ceph_put_cap(mdsc, cap);
1166
1167	if (!__ceph_is_any_real_caps(ci)) {
1168		/* when reconnect denied, we remove session caps forcibly,
1169		 * i_wr_ref can be non-zero. If there are ongoing write,
1170		 * keep i_snap_realm.
1171		 */
1172		if (ci->i_wr_ref == 0 && ci->i_snap_realm)
1173			ceph_change_snap_realm(&ci->netfs.inode, NULL);
1174
 
 
1175		__cap_delay_cancel(mdsc, ci);
1176	}
1177}
1178
1179void ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
1180{
1181	struct ceph_inode_info *ci = cap->ci;
1182	struct ceph_fs_client *fsc;
1183
1184	/* 'ci' being NULL means the remove have already occurred */
1185	if (!ci) {
1186		dout("%s: cap inode is NULL\n", __func__);
1187		return;
1188	}
1189
1190	lockdep_assert_held(&ci->i_ceph_lock);
1191
1192	fsc = ceph_inode_to_client(&ci->netfs.inode);
1193	WARN_ON_ONCE(ci->i_auth_cap == cap &&
1194		     !list_empty(&ci->i_dirty_item) &&
1195		     !fsc->blocklisted &&
1196		     !ceph_inode_is_shutdown(&ci->netfs.inode));
1197
1198	__ceph_remove_cap(cap, queue_release);
1199}
1200
1201struct cap_msg_args {
1202	struct ceph_mds_session	*session;
1203	u64			ino, cid, follows;
1204	u64			flush_tid, oldest_flush_tid, size, max_size;
1205	u64			xattr_version;
1206	u64			change_attr;
1207	struct ceph_buffer	*xattr_buf;
1208	struct ceph_buffer	*old_xattr_buf;
1209	struct timespec64	atime, mtime, ctime, btime;
1210	int			op, caps, wanted, dirty;
1211	u32			seq, issue_seq, mseq, time_warp_seq;
1212	u32			flags;
1213	kuid_t			uid;
1214	kgid_t			gid;
1215	umode_t			mode;
1216	bool			inline_data;
1217	bool			wake;
1218};
1219
1220/*
1221 * cap struct size + flock buffer size + inline version + inline data size +
1222 * osd_epoch_barrier + oldest_flush_tid
 
1223 */
1224#define CAP_MSG_SIZE (sizeof(struct ceph_mds_caps) + \
1225		      4 + 8 + 4 + 4 + 8 + 4 + 4 + 4 + 8 + 8 + 4)
1226
1227/* Marshal up the cap msg to the MDS */
1228static void encode_cap_msg(struct ceph_msg *msg, struct cap_msg_args *arg)
 
 
 
 
 
 
1229{
1230	struct ceph_mds_caps *fc;
1231	void *p;
1232	struct ceph_osd_client *osdc = &arg->session->s_mdsc->fsc->client->osdc;
1233
1234	dout("%s %s %llx %llx caps %s wanted %s dirty %s seq %u/%u tid %llu/%llu mseq %u follows %lld size %llu/%llu xattr_ver %llu xattr_len %d\n",
1235	     __func__, ceph_cap_op_name(arg->op), arg->cid, arg->ino,
1236	     ceph_cap_string(arg->caps), ceph_cap_string(arg->wanted),
1237	     ceph_cap_string(arg->dirty), arg->seq, arg->issue_seq,
1238	     arg->flush_tid, arg->oldest_flush_tid, arg->mseq, arg->follows,
1239	     arg->size, arg->max_size, arg->xattr_version,
1240	     arg->xattr_buf ? (int)arg->xattr_buf->vec.iov_len : 0);
1241
1242	msg->hdr.version = cpu_to_le16(10);
1243	msg->hdr.tid = cpu_to_le64(arg->flush_tid);
 
 
 
1244
1245	fc = msg->front.iov_base;
1246	memset(fc, 0, sizeof(*fc));
1247
1248	fc->cap_id = cpu_to_le64(arg->cid);
1249	fc->op = cpu_to_le32(arg->op);
1250	fc->seq = cpu_to_le32(arg->seq);
1251	fc->issue_seq = cpu_to_le32(arg->issue_seq);
1252	fc->migrate_seq = cpu_to_le32(arg->mseq);
1253	fc->caps = cpu_to_le32(arg->caps);
1254	fc->wanted = cpu_to_le32(arg->wanted);
1255	fc->dirty = cpu_to_le32(arg->dirty);
1256	fc->ino = cpu_to_le64(arg->ino);
1257	fc->snap_follows = cpu_to_le64(arg->follows);
1258
1259	fc->size = cpu_to_le64(arg->size);
1260	fc->max_size = cpu_to_le64(arg->max_size);
1261	ceph_encode_timespec64(&fc->mtime, &arg->mtime);
1262	ceph_encode_timespec64(&fc->atime, &arg->atime);
1263	ceph_encode_timespec64(&fc->ctime, &arg->ctime);
1264	fc->time_warp_seq = cpu_to_le32(arg->time_warp_seq);
1265
1266	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, arg->uid));
1267	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, arg->gid));
1268	fc->mode = cpu_to_le32(arg->mode);
1269
1270	fc->xattr_version = cpu_to_le64(arg->xattr_version);
1271	if (arg->xattr_buf) {
1272		msg->middle = ceph_buffer_get(arg->xattr_buf);
1273		fc->xattr_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1274		msg->hdr.middle_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1275	}
1276
1277	p = fc + 1;
1278	/* flock buffer size (version 2) */
1279	ceph_encode_32(&p, 0);
1280	/* inline version (version 4) */
1281	ceph_encode_64(&p, arg->inline_data ? 0 : CEPH_INLINE_NONE);
1282	/* inline data size */
1283	ceph_encode_32(&p, 0);
1284	/*
1285	 * osd_epoch_barrier (version 5)
1286	 * The epoch_barrier is protected osdc->lock, so READ_ONCE here in
1287	 * case it was recently changed
1288	 */
1289	ceph_encode_32(&p, READ_ONCE(osdc->epoch_barrier));
1290	/* oldest_flush_tid (version 6) */
1291	ceph_encode_64(&p, arg->oldest_flush_tid);
1292
1293	/*
1294	 * caller_uid/caller_gid (version 7)
1295	 *
1296	 * Currently, we don't properly track which caller dirtied the caps
1297	 * last, and force a flush of them when there is a conflict. For now,
1298	 * just set this to 0:0, to emulate how the MDS has worked up to now.
1299	 */
1300	ceph_encode_32(&p, 0);
1301	ceph_encode_32(&p, 0);
1302
1303	/* pool namespace (version 8) (mds always ignores this) */
1304	ceph_encode_32(&p, 0);
 
 
 
 
 
1305
1306	/* btime and change_attr (version 9) */
1307	ceph_encode_timespec64(p, &arg->btime);
1308	p += sizeof(struct ceph_timespec);
1309	ceph_encode_64(&p, arg->change_attr);
1310
1311	/* Advisory flags (version 10) */
1312	ceph_encode_32(&p, arg->flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1313}
1314
1315/*
1316 * Queue cap releases when an inode is dropped from our cache.
 
1317 */
1318void __ceph_remove_caps(struct ceph_inode_info *ci)
1319{
 
1320	struct rb_node *p;
1321
1322	/* lock i_ceph_lock, because ceph_d_revalidate(..., LOOKUP_RCU)
1323	 * may call __ceph_caps_issued_mask() on a freeing inode. */
1324	spin_lock(&ci->i_ceph_lock);
1325	p = rb_first(&ci->i_caps);
1326	while (p) {
1327		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1328		p = rb_next(p);
1329		ceph_remove_cap(cap, true);
1330	}
1331	spin_unlock(&ci->i_ceph_lock);
1332}
1333
1334/*
1335 * Prepare to send a cap message to an MDS. Update the cap state, and populate
1336 * the arg struct with the parameters that will need to be sent. This should
1337 * be done under the i_ceph_lock to guard against changes to cap state.
1338 *
1339 * Make note of max_size reported/requested from mds, revoked caps
1340 * that have now been implemented.
1341 */
1342static void __prep_cap(struct cap_msg_args *arg, struct ceph_cap *cap,
1343		       int op, int flags, int used, int want, int retain,
1344		       int flushing, u64 flush_tid, u64 oldest_flush_tid)
 
 
 
 
 
 
 
 
 
 
 
1345{
1346	struct ceph_inode_info *ci = cap->ci;
1347	struct inode *inode = &ci->netfs.inode;
1348	int held, revoking;
1349
1350	lockdep_assert_held(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
1351
1352	held = cap->issued | cap->implemented;
1353	revoking = cap->implemented & ~cap->issued;
1354	retain &= ~revoking;
 
1355
1356	dout("%s %p cap %p session %p %s -> %s (revoking %s)\n",
1357	     __func__, inode, cap, cap->session,
1358	     ceph_cap_string(held), ceph_cap_string(held & retain),
1359	     ceph_cap_string(revoking));
1360	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1361
1362	ci->i_ceph_flags &= ~CEPH_I_FLUSH;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1363
1364	cap->issued &= retain;  /* drop bits we don't want */
1365	/*
1366	 * Wake up any waiters on wanted -> needed transition. This is due to
1367	 * the weird transition from buffered to sync IO... we need to flush
1368	 * dirty pages _before_ allowing sync writes to avoid reordering.
1369	 */
1370	arg->wake = cap->implemented & ~cap->issued;
 
 
 
1371	cap->implemented &= cap->issued | used;
1372	cap->mds_wanted = want;
1373
1374	arg->session = cap->session;
1375	arg->ino = ceph_vino(inode).ino;
1376	arg->cid = cap->cap_id;
1377	arg->follows = flushing ? ci->i_head_snapc->seq : 0;
1378	arg->flush_tid = flush_tid;
1379	arg->oldest_flush_tid = oldest_flush_tid;
1380
1381	arg->size = i_size_read(inode);
1382	ci->i_reported_size = arg->size;
1383	arg->max_size = ci->i_wanted_max_size;
1384	if (cap == ci->i_auth_cap) {
1385		if (want & CEPH_CAP_ANY_FILE_WR)
1386			ci->i_requested_max_size = arg->max_size;
1387		else
1388			ci->i_requested_max_size = 0;
1389	}
1390
1391	if (flushing & CEPH_CAP_XATTR_EXCL) {
1392		arg->old_xattr_buf = __ceph_build_xattrs_blob(ci);
1393		arg->xattr_version = ci->i_xattrs.version;
1394		arg->xattr_buf = ci->i_xattrs.blob;
1395	} else {
1396		arg->xattr_buf = NULL;
1397		arg->old_xattr_buf = NULL;
1398	}
1399
1400	arg->mtime = inode->i_mtime;
1401	arg->atime = inode->i_atime;
1402	arg->ctime = inode->i_ctime;
1403	arg->btime = ci->i_btime;
1404	arg->change_attr = inode_peek_iversion_raw(inode);
1405
1406	arg->op = op;
1407	arg->caps = cap->implemented;
1408	arg->wanted = want;
1409	arg->dirty = flushing;
1410
1411	arg->seq = cap->seq;
1412	arg->issue_seq = cap->issue_seq;
1413	arg->mseq = cap->mseq;
1414	arg->time_warp_seq = ci->i_time_warp_seq;
1415
1416	arg->uid = inode->i_uid;
1417	arg->gid = inode->i_gid;
1418	arg->mode = inode->i_mode;
1419
1420	arg->inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1421	if (!(flags & CEPH_CLIENT_CAPS_PENDING_CAPSNAP) &&
1422	    !list_empty(&ci->i_cap_snaps)) {
1423		struct ceph_cap_snap *capsnap;
1424		list_for_each_entry_reverse(capsnap, &ci->i_cap_snaps, ci_item) {
1425			if (capsnap->cap_flush.tid)
1426				break;
1427			if (capsnap->need_flush) {
1428				flags |= CEPH_CLIENT_CAPS_PENDING_CAPSNAP;
1429				break;
1430			}
1431		}
1432	}
1433	arg->flags = flags;
1434}
1435
1436/*
1437 * Send a cap msg on the given inode.
1438 *
1439 * Caller should hold snap_rwsem (read), s_mutex.
1440 */
1441static void __send_cap(struct cap_msg_args *arg, struct ceph_inode_info *ci)
1442{
1443	struct ceph_msg *msg;
1444	struct inode *inode = &ci->netfs.inode;
1445
1446	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, CAP_MSG_SIZE, GFP_NOFS, false);
1447	if (!msg) {
1448		pr_err("error allocating cap msg: ino (%llx.%llx) flushing %s tid %llu, requeuing cap.\n",
1449		       ceph_vinop(inode), ceph_cap_string(arg->dirty),
1450		       arg->flush_tid);
1451		spin_lock(&ci->i_ceph_lock);
1452		__cap_delay_requeue(arg->session->s_mdsc, ci);
1453		spin_unlock(&ci->i_ceph_lock);
1454		return;
1455	}
1456
1457	encode_cap_msg(msg, arg);
1458	ceph_con_send(&arg->session->s_con, msg);
1459	ceph_buffer_put(arg->old_xattr_buf);
1460	if (arg->wake)
1461		wake_up_all(&ci->i_cap_wq);
1462}
1463
1464static inline int __send_flush_snap(struct inode *inode,
1465				    struct ceph_mds_session *session,
1466				    struct ceph_cap_snap *capsnap,
1467				    u32 mseq, u64 oldest_flush_tid)
1468{
1469	struct cap_msg_args	arg;
1470	struct ceph_msg		*msg;
1471
1472	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, CAP_MSG_SIZE, GFP_NOFS, false);
1473	if (!msg)
1474		return -ENOMEM;
1475
1476	arg.session = session;
1477	arg.ino = ceph_vino(inode).ino;
1478	arg.cid = 0;
1479	arg.follows = capsnap->follows;
1480	arg.flush_tid = capsnap->cap_flush.tid;
1481	arg.oldest_flush_tid = oldest_flush_tid;
1482
1483	arg.size = capsnap->size;
1484	arg.max_size = 0;
1485	arg.xattr_version = capsnap->xattr_version;
1486	arg.xattr_buf = capsnap->xattr_blob;
1487	arg.old_xattr_buf = NULL;
1488
1489	arg.atime = capsnap->atime;
1490	arg.mtime = capsnap->mtime;
1491	arg.ctime = capsnap->ctime;
1492	arg.btime = capsnap->btime;
1493	arg.change_attr = capsnap->change_attr;
1494
1495	arg.op = CEPH_CAP_OP_FLUSHSNAP;
1496	arg.caps = capsnap->issued;
1497	arg.wanted = 0;
1498	arg.dirty = capsnap->dirty;
1499
1500	arg.seq = 0;
1501	arg.issue_seq = 0;
1502	arg.mseq = mseq;
1503	arg.time_warp_seq = capsnap->time_warp_seq;
1504
1505	arg.uid = capsnap->uid;
1506	arg.gid = capsnap->gid;
1507	arg.mode = capsnap->mode;
1508
1509	arg.inline_data = capsnap->inline_data;
1510	arg.flags = 0;
1511	arg.wake = false;
1512
1513	encode_cap_msg(msg, &arg);
1514	ceph_con_send(&arg.session->s_con, msg);
1515	return 0;
1516}
1517
1518/*
1519 * When a snapshot is taken, clients accumulate dirty metadata on
1520 * inodes with capabilities in ceph_cap_snaps to describe the file
1521 * state at the time the snapshot was taken.  This must be flushed
1522 * asynchronously back to the MDS once sync writes complete and dirty
1523 * data is written out.
1524 *
1525 * Called under i_ceph_lock.
 
 
 
1526 */
1527static void __ceph_flush_snaps(struct ceph_inode_info *ci,
1528			       struct ceph_mds_session *session)
 
1529		__releases(ci->i_ceph_lock)
1530		__acquires(ci->i_ceph_lock)
1531{
1532	struct inode *inode = &ci->netfs.inode;
1533	struct ceph_mds_client *mdsc = session->s_mdsc;
1534	struct ceph_cap_snap *capsnap;
1535	u64 oldest_flush_tid = 0;
1536	u64 first_tid = 1, last_tid = 0;
 
 
 
 
 
1537
1538	dout("__flush_snaps %p session %p\n", inode, session);
 
1539
 
 
1540	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 
 
 
1541		/*
1542		 * we need to wait for sync writes to complete and for dirty
1543		 * pages to be written out.
1544		 */
1545		if (capsnap->dirty_pages || capsnap->writing)
1546			break;
1547
1548		/* should be removed by ceph_try_drop_cap_snap() */
1549		BUG_ON(!capsnap->need_flush);
 
 
 
 
 
 
 
 
 
1550
1551		/* only flush each capsnap once */
1552		if (capsnap->cap_flush.tid > 0) {
1553			dout(" already flushed %p, skipping\n", capsnap);
1554			continue;
1555		}
1556
1557		spin_lock(&mdsc->cap_dirty_lock);
1558		capsnap->cap_flush.tid = ++mdsc->last_cap_flush_tid;
1559		list_add_tail(&capsnap->cap_flush.g_list,
1560			      &mdsc->cap_flush_list);
1561		if (oldest_flush_tid == 0)
1562			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1563		if (list_empty(&ci->i_flushing_item)) {
1564			list_add_tail(&ci->i_flushing_item,
1565				      &session->s_cap_flushing);
1566		}
1567		spin_unlock(&mdsc->cap_dirty_lock);
1568
1569		list_add_tail(&capsnap->cap_flush.i_list,
1570			      &ci->i_cap_flush_list);
1571
1572		if (first_tid == 1)
1573			first_tid = capsnap->cap_flush.tid;
1574		last_tid = capsnap->cap_flush.tid;
1575	}
1576
1577	ci->i_ceph_flags &= ~CEPH_I_FLUSH_SNAPS;
1578
1579	while (first_tid <= last_tid) {
1580		struct ceph_cap *cap = ci->i_auth_cap;
1581		struct ceph_cap_flush *cf = NULL, *iter;
1582		int ret;
1583
1584		if (!(cap && cap->session == session)) {
1585			dout("__flush_snaps %p auth cap %p not mds%d, "
1586			     "stop\n", inode, cap, session->s_mds);
1587			break;
 
1588		}
1589
1590		ret = -ENOENT;
1591		list_for_each_entry(iter, &ci->i_cap_flush_list, i_list) {
1592			if (iter->tid >= first_tid) {
1593				cf = iter;
1594				ret = 0;
1595				break;
 
 
1596			}
 
 
 
 
 
 
 
1597		}
1598		if (ret < 0)
1599			break;
1600
1601		first_tid = cf->tid + 1;
1602
1603		capsnap = container_of(cf, struct ceph_cap_snap, cap_flush);
1604		refcount_inc(&capsnap->nref);
 
 
1605		spin_unlock(&ci->i_ceph_lock);
1606
1607		dout("__flush_snaps %p capsnap %p tid %llu %s\n",
1608		     inode, capsnap, cf->tid, ceph_cap_string(capsnap->dirty));
 
 
 
 
 
 
 
 
 
1609
1610		ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
1611					oldest_flush_tid);
1612		if (ret < 0) {
1613			pr_err("__flush_snaps: error sending cap flushsnap, "
1614			       "ino (%llx.%llx) tid %llu follows %llu\n",
1615				ceph_vinop(inode), cf->tid, capsnap->follows);
1616		}
1617
1618		ceph_put_cap_snap(capsnap);
1619		spin_lock(&ci->i_ceph_lock);
 
1620	}
1621}
1622
1623void ceph_flush_snaps(struct ceph_inode_info *ci,
1624		      struct ceph_mds_session **psession)
1625{
1626	struct inode *inode = &ci->netfs.inode;
1627	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1628	struct ceph_mds_session *session = NULL;
1629	int mds;
1630
1631	dout("ceph_flush_snaps %p\n", inode);
1632	if (psession)
1633		session = *psession;
1634retry:
1635	spin_lock(&ci->i_ceph_lock);
1636	if (!(ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)) {
1637		dout(" no capsnap needs flush, doing nothing\n");
1638		goto out;
1639	}
1640	if (!ci->i_auth_cap) {
1641		dout(" no auth cap (migrating?), doing nothing\n");
1642		goto out;
1643	}
1644
1645	mds = ci->i_auth_cap->session->s_mds;
1646	if (session && session->s_mds != mds) {
1647		dout(" oops, wrong session %p mutex\n", session);
1648		ceph_put_mds_session(session);
1649		session = NULL;
1650	}
1651	if (!session) {
1652		spin_unlock(&ci->i_ceph_lock);
1653		mutex_lock(&mdsc->mutex);
1654		session = __ceph_lookup_mds_session(mdsc, mds);
1655		mutex_unlock(&mdsc->mutex);
1656		goto retry;
1657	}
 
1658
1659	// make sure flushsnap messages are sent in proper order.
1660	if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
1661		__kick_flushing_caps(mdsc, session, ci, 0);
1662
1663	__ceph_flush_snaps(ci, session);
1664out:
1665	spin_unlock(&ci->i_ceph_lock);
1666
1667	if (psession)
1668		*psession = session;
1669	else
1670		ceph_put_mds_session(session);
1671	/* we flushed them all; remove this inode from the queue */
1672	spin_lock(&mdsc->snap_flush_lock);
1673	list_del_init(&ci->i_snap_flush_item);
1674	spin_unlock(&mdsc->snap_flush_lock);
1675}
1676
1677/*
1678 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1679 * Caller is then responsible for calling __mark_inode_dirty with the
1680 * returned flags value.
1681 */
1682int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask,
1683			   struct ceph_cap_flush **pcf)
1684{
1685	struct ceph_mds_client *mdsc =
1686		ceph_sb_to_client(ci->netfs.inode.i_sb)->mdsc;
1687	struct inode *inode = &ci->netfs.inode;
1688	int was = ci->i_dirty_caps;
1689	int dirty = 0;
1690
1691	lockdep_assert_held(&ci->i_ceph_lock);
1692
1693	if (!ci->i_auth_cap) {
1694		pr_warn("__mark_dirty_caps %p %llx mask %s, "
1695			"but no auth cap (session was closed?)\n",
1696			inode, ceph_ino(inode), ceph_cap_string(mask));
1697		return 0;
1698	}
1699
1700	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->netfs.inode,
1701	     ceph_cap_string(mask), ceph_cap_string(was),
1702	     ceph_cap_string(was | mask));
1703	ci->i_dirty_caps |= mask;
1704	if (was == 0) {
1705		struct ceph_mds_session *session = ci->i_auth_cap->session;
1706
1707		WARN_ON_ONCE(ci->i_prealloc_cap_flush);
1708		swap(ci->i_prealloc_cap_flush, *pcf);
1709
1710		if (!ci->i_head_snapc) {
1711			WARN_ON_ONCE(!rwsem_is_locked(&mdsc->snap_rwsem));
1712			ci->i_head_snapc = ceph_get_snap_context(
1713				ci->i_snap_realm->cached_context);
1714		}
1715		dout(" inode %p now dirty snapc %p auth cap %p\n",
1716		     &ci->netfs.inode, ci->i_head_snapc, ci->i_auth_cap);
 
1717		BUG_ON(!list_empty(&ci->i_dirty_item));
1718		spin_lock(&mdsc->cap_dirty_lock);
1719		list_add(&ci->i_dirty_item, &session->s_cap_dirty);
1720		spin_unlock(&mdsc->cap_dirty_lock);
1721		if (ci->i_flushing_caps == 0) {
1722			ihold(inode);
1723			dirty |= I_DIRTY_SYNC;
1724		}
1725	} else {
1726		WARN_ON_ONCE(!ci->i_prealloc_cap_flush);
1727	}
1728	BUG_ON(list_empty(&ci->i_dirty_item));
1729	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1730	    (mask & CEPH_CAP_FILE_BUFFER))
1731		dirty |= I_DIRTY_DATASYNC;
1732	__cap_delay_requeue(mdsc, ci);
1733	return dirty;
1734}
1735
1736struct ceph_cap_flush *ceph_alloc_cap_flush(void)
1737{
1738	struct ceph_cap_flush *cf;
1739
1740	cf = kmem_cache_alloc(ceph_cap_flush_cachep, GFP_KERNEL);
1741	if (!cf)
1742		return NULL;
1743
1744	cf->is_capsnap = false;
1745	return cf;
1746}
1747
1748void ceph_free_cap_flush(struct ceph_cap_flush *cf)
1749{
1750	if (cf)
1751		kmem_cache_free(ceph_cap_flush_cachep, cf);
1752}
1753
1754static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc)
1755{
1756	if (!list_empty(&mdsc->cap_flush_list)) {
1757		struct ceph_cap_flush *cf =
1758			list_first_entry(&mdsc->cap_flush_list,
1759					 struct ceph_cap_flush, g_list);
1760		return cf->tid;
1761	}
1762	return 0;
1763}
1764
1765/*
1766 * Remove cap_flush from the mdsc's or inode's flushing cap list.
1767 * Return true if caller needs to wake up flush waiters.
1768 */
1769static bool __detach_cap_flush_from_mdsc(struct ceph_mds_client *mdsc,
1770					 struct ceph_cap_flush *cf)
1771{
1772	struct ceph_cap_flush *prev;
1773	bool wake = cf->wake;
1774
1775	if (wake && cf->g_list.prev != &mdsc->cap_flush_list) {
1776		prev = list_prev_entry(cf, g_list);
1777		prev->wake = true;
1778		wake = false;
1779	}
1780	list_del_init(&cf->g_list);
1781	return wake;
1782}
1783
1784static bool __detach_cap_flush_from_ci(struct ceph_inode_info *ci,
1785				       struct ceph_cap_flush *cf)
1786{
1787	struct ceph_cap_flush *prev;
1788	bool wake = cf->wake;
1789
1790	if (wake && cf->i_list.prev != &ci->i_cap_flush_list) {
1791		prev = list_prev_entry(cf, i_list);
1792		prev->wake = true;
1793		wake = false;
1794	}
1795	list_del_init(&cf->i_list);
1796	return wake;
1797}
1798
1799/*
1800 * Add dirty inode to the flushing list.  Assigned a seq number so we
1801 * can wait for caps to flush without starving.
1802 *
1803 * Called under i_ceph_lock. Returns the flush tid.
1804 */
1805static u64 __mark_caps_flushing(struct inode *inode,
1806				struct ceph_mds_session *session, bool wake,
1807				u64 *oldest_flush_tid)
1808{
1809	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1810	struct ceph_inode_info *ci = ceph_inode(inode);
1811	struct ceph_cap_flush *cf = NULL;
1812	int flushing;
1813
1814	lockdep_assert_held(&ci->i_ceph_lock);
1815	BUG_ON(ci->i_dirty_caps == 0);
1816	BUG_ON(list_empty(&ci->i_dirty_item));
1817	BUG_ON(!ci->i_prealloc_cap_flush);
1818
1819	flushing = ci->i_dirty_caps;
1820	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1821	     ceph_cap_string(flushing),
1822	     ceph_cap_string(ci->i_flushing_caps),
1823	     ceph_cap_string(ci->i_flushing_caps | flushing));
1824	ci->i_flushing_caps |= flushing;
1825	ci->i_dirty_caps = 0;
1826	dout(" inode %p now !dirty\n", inode);
1827
1828	swap(cf, ci->i_prealloc_cap_flush);
1829	cf->caps = flushing;
1830	cf->wake = wake;
1831
1832	spin_lock(&mdsc->cap_dirty_lock);
1833	list_del_init(&ci->i_dirty_item);
1834
1835	cf->tid = ++mdsc->last_cap_flush_tid;
1836	list_add_tail(&cf->g_list, &mdsc->cap_flush_list);
1837	*oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1838
1839	if (list_empty(&ci->i_flushing_item)) {
1840		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1841		mdsc->num_cap_flushing++;
 
 
 
 
 
 
1842	}
1843	spin_unlock(&mdsc->cap_dirty_lock);
1844
1845	list_add_tail(&cf->i_list, &ci->i_cap_flush_list);
1846
1847	return cf->tid;
1848}
1849
1850/*
1851 * try to invalidate mapping pages without blocking.
1852 */
1853static int try_nonblocking_invalidate(struct inode *inode)
1854	__releases(ci->i_ceph_lock)
1855	__acquires(ci->i_ceph_lock)
1856{
1857	struct ceph_inode_info *ci = ceph_inode(inode);
1858	u32 invalidating_gen = ci->i_rdcache_gen;
1859
1860	spin_unlock(&ci->i_ceph_lock);
1861	ceph_fscache_invalidate(inode, false);
1862	invalidate_mapping_pages(&inode->i_data, 0, -1);
1863	spin_lock(&ci->i_ceph_lock);
1864
1865	if (inode->i_data.nrpages == 0 &&
1866	    invalidating_gen == ci->i_rdcache_gen) {
1867		/* success. */
1868		dout("try_nonblocking_invalidate %p success\n", inode);
1869		/* save any racing async invalidate some trouble */
1870		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1871		return 0;
1872	}
1873	dout("try_nonblocking_invalidate %p failed\n", inode);
1874	return -1;
1875}
1876
1877bool __ceph_should_report_size(struct ceph_inode_info *ci)
1878{
1879	loff_t size = i_size_read(&ci->netfs.inode);
1880	/* mds will adjust max size according to the reported size */
1881	if (ci->i_flushing_caps & CEPH_CAP_FILE_WR)
1882		return false;
1883	if (size >= ci->i_max_size)
1884		return true;
1885	/* half of previous max_size increment has been used */
1886	if (ci->i_max_size > ci->i_reported_size &&
1887	    (size << 1) >= ci->i_max_size + ci->i_reported_size)
1888		return true;
1889	return false;
1890}
1891
1892/*
1893 * Swiss army knife function to examine currently used and wanted
1894 * versus held caps.  Release, flush, ack revoked caps to mds as
1895 * appropriate.
1896 *
 
 
1897 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1898 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1899 *    further delay.
1900 */
1901void ceph_check_caps(struct ceph_inode_info *ci, int flags)
 
1902{
1903	struct inode *inode = &ci->netfs.inode;
1904	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
 
1905	struct ceph_cap *cap;
1906	u64 flush_tid, oldest_flush_tid;
1907	int file_wanted, used, cap_used;
 
1908	int issued, implemented, want, retain, revoking, flushing = 0;
1909	int mds = -1;   /* keep track of how far we've gone through i_caps list
1910			   to avoid an infinite loop on retry */
1911	struct rb_node *p;
1912	bool queue_invalidate = false;
1913	bool tried_invalidate = false;
1914	bool queue_writeback = false;
1915	struct ceph_mds_session *session = NULL;
 
 
 
 
1916
1917	spin_lock(&ci->i_ceph_lock);
1918	if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) {
1919		ci->i_ceph_flags |= CEPH_I_ASYNC_CHECK_CAPS;
1920
1921		/* Don't send messages until we get async create reply */
1922		spin_unlock(&ci->i_ceph_lock);
1923		return;
1924	}
1925
1926	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1927		flags |= CHECK_CAPS_FLUSH;
 
 
 
 
 
1928retry:
1929	/* Caps wanted by virtue of active open files. */
 
1930	file_wanted = __ceph_caps_file_wanted(ci);
1931
1932	/* Caps which have active references against them */
1933	used = __ceph_caps_used(ci);
1934
1935	/*
1936	 * "issued" represents the current caps that the MDS wants us to have.
1937	 * "implemented" is the set that we have been granted, and includes the
1938	 * ones that have not yet been returned to the MDS (the "revoking" set,
1939	 * usually because they have outstanding references).
1940	 */
1941	issued = __ceph_caps_issued(ci, &implemented);
1942	revoking = implemented & ~issued;
1943
1944	want = file_wanted;
1945
1946	/* The ones we currently want to retain (may be adjusted below) */
1947	retain = file_wanted | used | CEPH_CAP_PIN;
1948	if (!mdsc->stopping && inode->i_nlink > 0) {
1949		if (file_wanted) {
1950			retain |= CEPH_CAP_ANY;       /* be greedy */
1951		} else if (S_ISDIR(inode->i_mode) &&
1952			   (issued & CEPH_CAP_FILE_SHARED) &&
1953			   __ceph_dir_is_complete(ci)) {
1954			/*
1955			 * If a directory is complete, we want to keep
1956			 * the exclusive cap. So that MDS does not end up
1957			 * revoking the shared cap on every create/unlink
1958			 * operation.
1959			 */
1960			if (IS_RDONLY(inode)) {
1961				want = CEPH_CAP_ANY_SHARED;
1962			} else {
1963				want |= CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
1964			}
1965			retain |= want;
1966		} else {
1967
1968			retain |= CEPH_CAP_ANY_SHARED;
1969			/*
1970			 * keep RD only if we didn't have the file open RW,
1971			 * because then the mds would revoke it anyway to
1972			 * journal max_size=0.
1973			 */
1974			if (ci->i_max_size == 0)
1975				retain |= CEPH_CAP_ANY_RD;
1976		}
1977	}
1978
1979	dout("check_caps %llx.%llx file_want %s used %s dirty %s flushing %s"
1980	     " issued %s revoking %s retain %s %s%s%s\n", ceph_vinop(inode),
1981	     ceph_cap_string(file_wanted),
1982	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1983	     ceph_cap_string(ci->i_flushing_caps),
1984	     ceph_cap_string(issued), ceph_cap_string(revoking),
1985	     ceph_cap_string(retain),
1986	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1987	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "",
1988	     (flags & CHECK_CAPS_NOINVAL) ? " NOINVAL" : "");
1989
1990	/*
1991	 * If we no longer need to hold onto old our caps, and we may
1992	 * have cached pages, but don't want them, then try to invalidate.
1993	 * If we fail, it's because pages are locked.... try again later.
1994	 */
1995	if ((!(flags & CHECK_CAPS_NOINVAL) || mdsc->stopping) &&
1996	    S_ISREG(inode->i_mode) &&
1997	    !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
1998	    inode->i_data.nrpages &&		/* have cached pages */
1999	    (revoking & (CEPH_CAP_FILE_CACHE|
2000			 CEPH_CAP_FILE_LAZYIO)) && /*  or revoking cache */
2001	    !tried_invalidate) {
2002		dout("check_caps trying to invalidate on %llx.%llx\n",
2003		     ceph_vinop(inode));
2004		if (try_nonblocking_invalidate(inode) < 0) {
2005			dout("check_caps queuing invalidate\n");
2006			queue_invalidate = true;
2007			ci->i_rdcache_revoking = ci->i_rdcache_gen;
 
 
 
 
 
 
 
 
 
2008		}
2009		tried_invalidate = true;
2010		goto retry;
2011	}
2012
 
2013	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
2014		int mflags = 0;
2015		struct cap_msg_args arg;
2016
2017		cap = rb_entry(p, struct ceph_cap, ci_node);
 
2018
2019		/* avoid looping forever */
2020		if (mds >= cap->mds ||
2021		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
2022			continue;
2023
2024		/*
2025		 * If we have an auth cap, we don't need to consider any
2026		 * overlapping caps as used.
2027		 */
2028		cap_used = used;
2029		if (ci->i_auth_cap && cap != ci->i_auth_cap)
2030			cap_used &= ~ci->i_auth_cap->issued;
2031
2032		revoking = cap->implemented & ~cap->issued;
2033		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
2034		     cap->mds, cap, ceph_cap_string(cap_used),
2035		     ceph_cap_string(cap->issued),
2036		     ceph_cap_string(cap->implemented),
2037		     ceph_cap_string(revoking));
2038
2039		if (cap == ci->i_auth_cap &&
2040		    (cap->issued & CEPH_CAP_FILE_WR)) {
2041			/* request larger max_size from MDS? */
2042			if (ci->i_wanted_max_size > ci->i_max_size &&
2043			    ci->i_wanted_max_size > ci->i_requested_max_size) {
2044				dout("requesting new max_size\n");
2045				goto ack;
2046			}
2047
2048			/* approaching file_max? */
2049			if (__ceph_should_report_size(ci)) {
 
2050				dout("i_size approaching max_size\n");
2051				goto ack;
2052			}
2053		}
2054		/* flush anything dirty? */
2055		if (cap == ci->i_auth_cap) {
2056			if ((flags & CHECK_CAPS_FLUSH) && ci->i_dirty_caps) {
2057				dout("flushing dirty caps\n");
2058				goto ack;
2059			}
2060			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS) {
2061				dout("flushing snap caps\n");
2062				goto ack;
2063			}
2064		}
2065
2066		/* completed revocation? going down and there are no caps? */
2067		if (revoking) {
2068			if ((revoking & cap_used) == 0) {
2069				dout("completed revocation of %s\n",
2070				      ceph_cap_string(cap->implemented & ~cap->issued));
2071				goto ack;
2072			}
2073
2074			/*
2075			 * If the "i_wrbuffer_ref" was increased by mmap or generic
2076			 * cache write just before the ceph_check_caps() is called,
2077			 * the Fb capability revoking will fail this time. Then we
2078			 * must wait for the BDI's delayed work to flush the dirty
2079			 * pages and to release the "i_wrbuffer_ref", which will cost
2080			 * at most 5 seconds. That means the MDS needs to wait at
2081			 * most 5 seconds to finished the Fb capability's revocation.
2082			 *
2083			 * Let's queue a writeback for it.
2084			 */
2085			if (S_ISREG(inode->i_mode) && ci->i_wrbuffer_ref &&
2086			    (revoking & CEPH_CAP_FILE_BUFFER))
2087				queue_writeback = true;
2088		}
2089
2090		/* want more caps from mds? */
2091		if (want & ~cap->mds_wanted) {
2092			if (want & ~(cap->mds_wanted | cap->issued))
2093				goto ack;
2094			if (!__cap_is_valid(cap))
2095				goto ack;
2096		}
2097
2098		/* things we might delay */
2099		if ((cap->issued & ~retain) == 0)
 
2100			continue;     /* nope, all good */
2101
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2102ack:
2103		ceph_put_mds_session(session);
2104		session = ceph_get_mds_session(cap->session);
 
 
2105
2106		/* kick flushing and flush snaps before sending normal
2107		 * cap message */
2108		if (cap == ci->i_auth_cap &&
2109		    (ci->i_ceph_flags &
2110		     (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS))) {
2111			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2112				__kick_flushing_caps(mdsc, session, ci, 0);
2113			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2114				__ceph_flush_snaps(ci, session);
2115
2116			goto retry;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2117		}
2118
2119		if (cap == ci->i_auth_cap && ci->i_dirty_caps) {
2120			flushing = ci->i_dirty_caps;
2121			flush_tid = __mark_caps_flushing(inode, session, false,
2122							 &oldest_flush_tid);
2123			if (flags & CHECK_CAPS_FLUSH &&
2124			    list_empty(&session->s_cap_dirty))
2125				mflags |= CEPH_CLIENT_CAPS_SYNC;
2126		} else {
2127			flushing = 0;
2128			flush_tid = 0;
2129			spin_lock(&mdsc->cap_dirty_lock);
2130			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2131			spin_unlock(&mdsc->cap_dirty_lock);
2132		}
2133
2134		mds = cap->mds;  /* remember mds, so we don't repeat */
 
2135
2136		__prep_cap(&arg, cap, CEPH_CAP_OP_UPDATE, mflags, cap_used,
2137			   want, retain, flushing, flush_tid, oldest_flush_tid);
2138
2139		spin_unlock(&ci->i_ceph_lock);
2140		__send_cap(&arg, ci);
2141		spin_lock(&ci->i_ceph_lock);
2142
2143		goto retry; /* retake i_ceph_lock and restart our cap scan. */
2144	}
2145
2146	/* periodically re-calculate caps wanted by open files */
2147	if (__ceph_is_any_real_caps(ci) &&
2148	    list_empty(&ci->i_cap_delay_list) &&
2149	    (file_wanted & ~CEPH_CAP_PIN) &&
2150	    !(used & (CEPH_CAP_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
 
 
 
 
2151		__cap_delay_requeue(mdsc, ci);
2152	}
2153
2154	spin_unlock(&ci->i_ceph_lock);
2155
2156	ceph_put_mds_session(session);
2157	if (queue_writeback)
2158		ceph_queue_writeback(inode);
2159	if (queue_invalidate)
2160		ceph_queue_invalidate(inode);
 
 
 
 
 
2161}
2162
2163/*
2164 * Try to flush dirty caps back to the auth mds.
2165 */
2166static int try_flush_caps(struct inode *inode, u64 *ptid)
2167{
2168	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2169	struct ceph_inode_info *ci = ceph_inode(inode);
2170	int flushing = 0;
2171	u64 flush_tid = 0, oldest_flush_tid = 0;
2172
 
2173	spin_lock(&ci->i_ceph_lock);
2174retry_locked:
 
 
 
2175	if (ci->i_dirty_caps && ci->i_auth_cap) {
2176		struct ceph_cap *cap = ci->i_auth_cap;
2177		struct cap_msg_args arg;
2178		struct ceph_mds_session *session = cap->session;
 
2179
2180		if (session->s_state < CEPH_MDS_SESSION_OPEN) {
2181			spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
2182			goto out;
2183		}
2184
2185		if (ci->i_ceph_flags &
2186		    (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS)) {
2187			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2188				__kick_flushing_caps(mdsc, session, ci, 0);
2189			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2190				__ceph_flush_snaps(ci, session);
2191			goto retry_locked;
2192		}
2193
2194		flushing = ci->i_dirty_caps;
2195		flush_tid = __mark_caps_flushing(inode, session, true,
2196						 &oldest_flush_tid);
2197
2198		__prep_cap(&arg, cap, CEPH_CAP_OP_FLUSH, CEPH_CLIENT_CAPS_SYNC,
2199			   __ceph_caps_used(ci), __ceph_caps_wanted(ci),
2200			   (cap->issued | cap->implemented),
2201			   flushing, flush_tid, oldest_flush_tid);
2202		spin_unlock(&ci->i_ceph_lock);
2203
2204		__send_cap(&arg, ci);
2205	} else {
2206		if (!list_empty(&ci->i_cap_flush_list)) {
2207			struct ceph_cap_flush *cf =
2208				list_last_entry(&ci->i_cap_flush_list,
2209						struct ceph_cap_flush, i_list);
2210			cf->wake = true;
2211			flush_tid = cf->tid;
2212		}
2213		flushing = ci->i_flushing_caps;
2214		spin_unlock(&ci->i_ceph_lock);
2215	}
2216out:
2217	*ptid = flush_tid;
 
 
 
2218	return flushing;
2219}
2220
2221/*
2222 * Return true if we've flushed caps through the given flush_tid.
2223 */
2224static int caps_are_flushed(struct inode *inode, u64 flush_tid)
2225{
2226	struct ceph_inode_info *ci = ceph_inode(inode);
2227	int ret = 1;
2228
2229	spin_lock(&ci->i_ceph_lock);
2230	if (!list_empty(&ci->i_cap_flush_list)) {
2231		struct ceph_cap_flush * cf =
2232			list_first_entry(&ci->i_cap_flush_list,
2233					 struct ceph_cap_flush, i_list);
2234		if (cf->tid <= flush_tid)
2235			ret = 0;
2236	}
 
2237	spin_unlock(&ci->i_ceph_lock);
2238	return ret;
2239}
2240
2241/*
2242 * flush the mdlog and wait for any unsafe requests to complete.
 
 
 
2243 */
2244static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode)
2245{
2246	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2247	struct ceph_inode_info *ci = ceph_inode(inode);
2248	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
2249	int ret, err = 0;
 
2250
2251	spin_lock(&ci->i_unsafe_lock);
2252	if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) {
2253		req1 = list_last_entry(&ci->i_unsafe_dirops,
2254					struct ceph_mds_request,
2255					r_unsafe_dir_item);
2256		ceph_mdsc_get_request(req1);
2257	}
2258	if (!list_empty(&ci->i_unsafe_iops)) {
2259		req2 = list_last_entry(&ci->i_unsafe_iops,
2260					struct ceph_mds_request,
2261					r_unsafe_target_item);
2262		ceph_mdsc_get_request(req2);
2263	}
2264	spin_unlock(&ci->i_unsafe_lock);
2265
2266	/*
2267	 * Trigger to flush the journal logs in all the relevant MDSes
2268	 * manually, or in the worst case we must wait at most 5 seconds
2269	 * to wait the journal logs to be flushed by the MDSes periodically.
2270	 */
2271	if (req1 || req2) {
2272		struct ceph_mds_request *req;
2273		struct ceph_mds_session **sessions;
2274		struct ceph_mds_session *s;
2275		unsigned int max_sessions;
2276		int i;
2277
2278		mutex_lock(&mdsc->mutex);
2279		max_sessions = mdsc->max_sessions;
2280
2281		sessions = kcalloc(max_sessions, sizeof(s), GFP_KERNEL);
2282		if (!sessions) {
2283			mutex_unlock(&mdsc->mutex);
2284			err = -ENOMEM;
2285			goto out;
2286		}
2287
 
 
 
 
 
 
2288		spin_lock(&ci->i_unsafe_lock);
2289		if (req1) {
2290			list_for_each_entry(req, &ci->i_unsafe_dirops,
2291					    r_unsafe_dir_item) {
2292				s = req->r_session;
2293				if (!s)
2294					continue;
2295				if (!sessions[s->s_mds]) {
2296					s = ceph_get_mds_session(s);
2297					sessions[s->s_mds] = s;
2298				}
2299			}
2300		}
2301		if (req2) {
2302			list_for_each_entry(req, &ci->i_unsafe_iops,
2303					    r_unsafe_target_item) {
2304				s = req->r_session;
2305				if (!s)
2306					continue;
2307				if (!sessions[s->s_mds]) {
2308					s = ceph_get_mds_session(s);
2309					sessions[s->s_mds] = s;
2310				}
2311			}
2312		}
2313		spin_unlock(&ci->i_unsafe_lock);
2314
2315		/* the auth MDS */
2316		spin_lock(&ci->i_ceph_lock);
2317		if (ci->i_auth_cap) {
2318			s = ci->i_auth_cap->session;
2319			if (!sessions[s->s_mds])
2320				sessions[s->s_mds] = ceph_get_mds_session(s);
2321		}
2322		spin_unlock(&ci->i_ceph_lock);
2323		mutex_unlock(&mdsc->mutex);
2324
2325		/* send flush mdlog request to MDSes */
2326		for (i = 0; i < max_sessions; i++) {
2327			s = sessions[i];
2328			if (s) {
2329				send_flush_mdlog(s);
2330				ceph_put_mds_session(s);
2331			}
2332		}
2333		kfree(sessions);
2334	}
2335
2336	dout("%s %p wait on tid %llu %llu\n", __func__,
2337	     inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL);
2338	if (req1) {
2339		ret = !wait_for_completion_timeout(&req1->r_safe_completion,
2340					ceph_timeout_jiffies(req1->r_timeout));
2341		if (ret)
2342			err = -EIO;
2343	}
2344	if (req2) {
2345		ret = !wait_for_completion_timeout(&req2->r_safe_completion,
2346					ceph_timeout_jiffies(req2->r_timeout));
2347		if (ret)
2348			err = -EIO;
2349	}
2350
 
 
 
 
 
 
 
 
 
2351out:
2352	if (req1)
2353		ceph_mdsc_put_request(req1);
2354	if (req2)
2355		ceph_mdsc_put_request(req2);
2356	return err;
2357}
2358
2359int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2360{
2361	struct inode *inode = file->f_mapping->host;
2362	struct ceph_inode_info *ci = ceph_inode(inode);
2363	u64 flush_tid;
2364	int ret, err;
2365	int dirty;
2366
2367	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
 
2368
2369	ret = file_write_and_wait_range(file, start, end);
2370	if (datasync)
2371		goto out;
2372
2373	ret = ceph_wait_on_async_create(inode);
2374	if (ret)
2375		goto out;
2376
2377	dirty = try_flush_caps(inode, &flush_tid);
2378	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
2379
2380	err = flush_mdlog_and_wait_inode_unsafe_requests(inode);
2381
2382	/*
2383	 * only wait on non-file metadata writeback (the mds
2384	 * can recover size and mtime, so we don't need to
2385	 * wait for that)
2386	 */
2387	if (!err && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
2388		err = wait_event_interruptible(ci->i_cap_wq,
2389					caps_are_flushed(inode, flush_tid));
 
2390	}
2391
2392	if (err < 0)
2393		ret = err;
2394
2395	err = file_check_and_advance_wb_err(file);
2396	if (err < 0)
2397		ret = err;
2398out:
2399	dout("fsync %p%s result=%d\n", inode, datasync ? " datasync" : "", ret);
2400	return ret;
2401}
2402
2403/*
2404 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
2405 * queue inode for flush but don't do so immediately, because we can
2406 * get by with fewer MDS messages if we wait for data writeback to
2407 * complete first.
2408 */
2409int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
2410{
2411	struct ceph_inode_info *ci = ceph_inode(inode);
2412	u64 flush_tid;
2413	int err = 0;
2414	int dirty;
2415	int wait = (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync);
2416
2417	dout("write_inode %p wait=%d\n", inode, wait);
2418	ceph_fscache_unpin_writeback(inode, wbc);
2419	if (wait) {
2420		err = ceph_wait_on_async_create(inode);
2421		if (err)
2422			return err;
2423		dirty = try_flush_caps(inode, &flush_tid);
2424		if (dirty)
2425			err = wait_event_interruptible(ci->i_cap_wq,
2426				       caps_are_flushed(inode, flush_tid));
2427	} else {
2428		struct ceph_mds_client *mdsc =
2429			ceph_sb_to_client(inode->i_sb)->mdsc;
2430
2431		spin_lock(&ci->i_ceph_lock);
2432		if (__ceph_caps_dirty(ci))
2433			__cap_delay_requeue_front(mdsc, ci);
2434		spin_unlock(&ci->i_ceph_lock);
2435	}
2436	return err;
2437}
2438
2439static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
2440				 struct ceph_mds_session *session,
2441				 struct ceph_inode_info *ci,
2442				 u64 oldest_flush_tid)
2443	__releases(ci->i_ceph_lock)
2444	__acquires(ci->i_ceph_lock)
2445{
2446	struct inode *inode = &ci->netfs.inode;
2447	struct ceph_cap *cap;
2448	struct ceph_cap_flush *cf;
2449	int ret;
2450	u64 first_tid = 0;
2451	u64 last_snap_flush = 0;
2452
2453	/* Don't do anything until create reply comes in */
2454	if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE)
2455		return;
2456
2457	ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2458
2459	list_for_each_entry_reverse(cf, &ci->i_cap_flush_list, i_list) {
2460		if (cf->is_capsnap) {
2461			last_snap_flush = cf->tid;
2462			break;
2463		}
2464	}
2465
2466	list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
2467		if (cf->tid < first_tid)
2468			continue;
2469
2470		cap = ci->i_auth_cap;
2471		if (!(cap && cap->session == session)) {
2472			pr_err("%p auth cap %p not mds%d ???\n",
2473			       inode, cap, session->s_mds);
2474			break;
2475		}
2476
2477		first_tid = cf->tid + 1;
2478
2479		if (!cf->is_capsnap) {
2480			struct cap_msg_args arg;
2481
2482			dout("kick_flushing_caps %p cap %p tid %llu %s\n",
2483			     inode, cap, cf->tid, ceph_cap_string(cf->caps));
2484			__prep_cap(&arg, cap, CEPH_CAP_OP_FLUSH,
2485					 (cf->tid < last_snap_flush ?
2486					  CEPH_CLIENT_CAPS_PENDING_CAPSNAP : 0),
2487					  __ceph_caps_used(ci),
2488					  __ceph_caps_wanted(ci),
2489					  (cap->issued | cap->implemented),
2490					  cf->caps, cf->tid, oldest_flush_tid);
2491			spin_unlock(&ci->i_ceph_lock);
2492			__send_cap(&arg, ci);
2493		} else {
2494			struct ceph_cap_snap *capsnap =
2495					container_of(cf, struct ceph_cap_snap,
2496						    cap_flush);
2497			dout("kick_flushing_caps %p capsnap %p tid %llu %s\n",
2498			     inode, capsnap, cf->tid,
2499			     ceph_cap_string(capsnap->dirty));
2500
2501			refcount_inc(&capsnap->nref);
2502			spin_unlock(&ci->i_ceph_lock);
2503
2504			ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
2505						oldest_flush_tid);
2506			if (ret < 0) {
2507				pr_err("kick_flushing_caps: error sending "
2508					"cap flushsnap, ino (%llx.%llx) "
2509					"tid %llu follows %llu\n",
2510					ceph_vinop(inode), cf->tid,
2511					capsnap->follows);
2512			}
2513
2514			ceph_put_cap_snap(capsnap);
2515		}
2516
2517		spin_lock(&ci->i_ceph_lock);
2518	}
2519}
2520
2521void ceph_early_kick_flushing_caps(struct ceph_mds_client *mdsc,
2522				   struct ceph_mds_session *session)
2523{
2524	struct ceph_inode_info *ci;
2525	struct ceph_cap *cap;
2526	u64 oldest_flush_tid;
2527
2528	dout("early_kick_flushing_caps mds%d\n", session->s_mds);
2529
2530	spin_lock(&mdsc->cap_dirty_lock);
2531	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2532	spin_unlock(&mdsc->cap_dirty_lock);
 
2533
2534	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2535		spin_lock(&ci->i_ceph_lock);
2536		cap = ci->i_auth_cap;
2537		if (!(cap && cap->session == session)) {
2538			pr_err("%p auth cap %p not mds%d ???\n",
2539				&ci->netfs.inode, cap, session->s_mds);
2540			spin_unlock(&ci->i_ceph_lock);
2541			continue;
2542		}
2543
2544
2545		/*
2546		 * if flushing caps were revoked, we re-send the cap flush
2547		 * in client reconnect stage. This guarantees MDS * processes
2548		 * the cap flush message before issuing the flushing caps to
2549		 * other client.
2550		 */
2551		if ((cap->issued & ci->i_flushing_caps) !=
2552		    ci->i_flushing_caps) {
2553			/* encode_caps_cb() also will reset these sequence
2554			 * numbers. make sure sequence numbers in cap flush
2555			 * message match later reconnect message */
2556			cap->seq = 0;
2557			cap->issue_seq = 0;
2558			cap->mseq = 0;
2559			__kick_flushing_caps(mdsc, session, ci,
2560					     oldest_flush_tid);
2561		} else {
2562			ci->i_ceph_flags |= CEPH_I_KICK_FLUSH;
 
2563		}
2564
2565		spin_unlock(&ci->i_ceph_lock);
2566	}
2567}
2568
2569void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
2570			     struct ceph_mds_session *session)
2571{
2572	struct ceph_inode_info *ci;
2573	struct ceph_cap *cap;
2574	u64 oldest_flush_tid;
2575
2576	lockdep_assert_held(&session->s_mutex);
2577
2578	dout("kick_flushing_caps mds%d\n", session->s_mds);
 
 
 
 
2579
2580	spin_lock(&mdsc->cap_dirty_lock);
2581	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2582	spin_unlock(&mdsc->cap_dirty_lock);
2583
2584	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2585		spin_lock(&ci->i_ceph_lock);
2586		cap = ci->i_auth_cap;
2587		if (!(cap && cap->session == session)) {
2588			pr_err("%p auth cap %p not mds%d ???\n",
2589				&ci->netfs.inode, cap, session->s_mds);
 
 
 
 
 
 
 
 
 
 
 
 
 
2590			spin_unlock(&ci->i_ceph_lock);
2591			continue;
2592		}
2593		if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
2594			__kick_flushing_caps(mdsc, session, ci,
2595					     oldest_flush_tid);
2596		}
2597		spin_unlock(&ci->i_ceph_lock);
2598	}
2599}
2600
2601void ceph_kick_flushing_inode_caps(struct ceph_mds_session *session,
2602				   struct ceph_inode_info *ci)
 
2603{
2604	struct ceph_mds_client *mdsc = session->s_mdsc;
2605	struct ceph_cap *cap = ci->i_auth_cap;
 
2606
2607	lockdep_assert_held(&ci->i_ceph_lock);
 
 
 
2608
2609	dout("%s %p flushing %s\n", __func__, &ci->netfs.inode,
2610	     ceph_cap_string(ci->i_flushing_caps));
2611
2612	if (!list_empty(&ci->i_cap_flush_list)) {
2613		u64 oldest_flush_tid;
2614		spin_lock(&mdsc->cap_dirty_lock);
2615		list_move_tail(&ci->i_flushing_item,
2616			       &cap->session->s_cap_flushing);
2617		oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2618		spin_unlock(&mdsc->cap_dirty_lock);
2619
2620		__kick_flushing_caps(mdsc, session, ci, oldest_flush_tid);
 
 
 
 
 
 
 
 
 
 
 
2621	}
2622}
2623
2624
2625/*
2626 * Take references to capabilities we hold, so that we don't release
2627 * them to the MDS prematurely.
 
 
2628 */
2629void ceph_take_cap_refs(struct ceph_inode_info *ci, int got,
2630			    bool snap_rwsem_locked)
2631{
2632	lockdep_assert_held(&ci->i_ceph_lock);
2633
2634	if (got & CEPH_CAP_PIN)
2635		ci->i_pin_ref++;
2636	if (got & CEPH_CAP_FILE_RD)
2637		ci->i_rd_ref++;
2638	if (got & CEPH_CAP_FILE_CACHE)
2639		ci->i_rdcache_ref++;
2640	if (got & CEPH_CAP_FILE_EXCL)
2641		ci->i_fx_ref++;
2642	if (got & CEPH_CAP_FILE_WR) {
2643		if (ci->i_wr_ref == 0 && !ci->i_head_snapc) {
2644			BUG_ON(!snap_rwsem_locked);
2645			ci->i_head_snapc = ceph_get_snap_context(
2646					ci->i_snap_realm->cached_context);
2647		}
2648		ci->i_wr_ref++;
2649	}
2650	if (got & CEPH_CAP_FILE_BUFFER) {
2651		if (ci->i_wb_ref == 0)
2652			ihold(&ci->netfs.inode);
2653		ci->i_wb_ref++;
2654		dout("%s %p wb %d -> %d (?)\n", __func__,
2655		     &ci->netfs.inode, ci->i_wb_ref-1, ci->i_wb_ref);
2656	}
2657}
2658
2659/*
2660 * Try to grab cap references.  Specify those refs we @want, and the
2661 * minimal set we @need.  Also include the larger offset we are writing
2662 * to (when applicable), and check against max_size here as well.
2663 * Note that caller is responsible for ensuring max_size increases are
2664 * requested from the MDS.
2665 *
2666 * Returns 0 if caps were not able to be acquired (yet), 1 if succeed,
2667 * or a negative error code. There are 3 speical error codes:
2668 *  -EAGAIN:  need to sleep but non-blocking is specified
2669 *  -EFBIG:   ask caller to call check_max_size() and try again.
2670 *  -EUCLEAN: ask caller to call ceph_renew_caps() and try again.
2671 */
2672enum {
2673	/* first 8 bits are reserved for CEPH_FILE_MODE_FOO */
2674	NON_BLOCKING	= (1 << 8),
2675	CHECK_FILELOCK	= (1 << 9),
2676};
2677
2678static int try_get_cap_refs(struct inode *inode, int need, int want,
2679			    loff_t endoff, int flags, int *got)
2680{
2681	struct ceph_inode_info *ci = ceph_inode(inode);
2682	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2683	int ret = 0;
2684	int have, implemented;
2685	bool snap_rwsem_locked = false;
2686
2687	dout("get_cap_refs %p need %s want %s\n", inode,
2688	     ceph_cap_string(need), ceph_cap_string(want));
2689
2690again:
2691	spin_lock(&ci->i_ceph_lock);
2692
2693	if ((flags & CHECK_FILELOCK) &&
2694	    (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK)) {
2695		dout("try_get_cap_refs %p error filelock\n", inode);
2696		ret = -EIO;
2697		goto out_unlock;
 
 
 
2698	}
2699
2700	/* finish pending truncate */
2701	while (ci->i_truncate_pending) {
2702		spin_unlock(&ci->i_ceph_lock);
2703		if (snap_rwsem_locked) {
2704			up_read(&mdsc->snap_rwsem);
2705			snap_rwsem_locked = false;
2706		}
2707		__ceph_do_pending_vmtruncate(inode);
2708		spin_lock(&ci->i_ceph_lock);
2709	}
2710
2711	have = __ceph_caps_issued(ci, &implemented);
2712
2713	if (have & need & CEPH_CAP_FILE_WR) {
2714		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2715			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2716			     inode, endoff, ci->i_max_size);
2717			if (endoff > ci->i_requested_max_size)
2718				ret = ci->i_auth_cap ? -EFBIG : -EUCLEAN;
2719			goto out_unlock;
 
 
2720		}
2721		/*
2722		 * If a sync write is in progress, we must wait, so that we
2723		 * can get a final snapshot value for size+mtime.
2724		 */
2725		if (__ceph_have_pending_cap_snap(ci)) {
2726			dout("get_cap_refs %p cap_snap_pending\n", inode);
2727			goto out_unlock;
2728		}
2729	}
2730
2731	if ((have & need) == need) {
2732		/*
2733		 * Look at (implemented & ~have & not) so that we keep waiting
2734		 * on transition from wanted -> needed caps.  This is needed
2735		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2736		 * going before a prior buffered writeback happens.
2737		 *
2738		 * For RDCACHE|RD -> RD, there is not need to wait and we can
2739		 * just exclude the revoking caps and force to sync read.
2740		 */
2741		int not = want & ~(have & need);
2742		int revoking = implemented & ~have;
2743		int exclude = revoking & not;
2744		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2745		     inode, ceph_cap_string(have), ceph_cap_string(not),
2746		     ceph_cap_string(revoking));
2747		if (!exclude || !(exclude & CEPH_CAP_FILE_BUFFER)) {
2748			if (!snap_rwsem_locked &&
2749			    !ci->i_head_snapc &&
2750			    (need & CEPH_CAP_FILE_WR)) {
2751				if (!down_read_trylock(&mdsc->snap_rwsem)) {
2752					/*
2753					 * we can not call down_read() when
2754					 * task isn't in TASK_RUNNING state
2755					 */
2756					if (flags & NON_BLOCKING) {
2757						ret = -EAGAIN;
2758						goto out_unlock;
2759					}
2760
2761					spin_unlock(&ci->i_ceph_lock);
2762					down_read(&mdsc->snap_rwsem);
2763					snap_rwsem_locked = true;
2764					goto again;
2765				}
2766				snap_rwsem_locked = true;
2767			}
2768			if ((have & want) == want)
2769				*got = need | (want & ~exclude);
2770			else
2771				*got = need;
2772			ceph_take_cap_refs(ci, *got, true);
2773			ret = 1;
2774		}
2775	} else {
2776		int session_readonly = false;
2777		int mds_wanted;
2778		if (ci->i_auth_cap &&
2779		    (need & (CEPH_CAP_FILE_WR | CEPH_CAP_FILE_EXCL))) {
2780			struct ceph_mds_session *s = ci->i_auth_cap->session;
2781			spin_lock(&s->s_cap_lock);
2782			session_readonly = s->s_readonly;
2783			spin_unlock(&s->s_cap_lock);
2784		}
2785		if (session_readonly) {
2786			dout("get_cap_refs %p need %s but mds%d readonly\n",
2787			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
2788			ret = -EROFS;
2789			goto out_unlock;
2790		}
2791
2792		if (ceph_inode_is_shutdown(inode)) {
2793			dout("get_cap_refs %p inode is shutdown\n", inode);
2794			ret = -ESTALE;
2795			goto out_unlock;
2796		}
2797		mds_wanted = __ceph_caps_mds_wanted(ci, false);
2798		if (need & ~mds_wanted) {
2799			dout("get_cap_refs %p need %s > mds_wanted %s\n",
2800			     inode, ceph_cap_string(need),
2801			     ceph_cap_string(mds_wanted));
2802			ret = -EUCLEAN;
2803			goto out_unlock;
2804		}
2805
2806		dout("get_cap_refs %p have %s need %s\n", inode,
2807		     ceph_cap_string(have), ceph_cap_string(need));
2808	}
2809out_unlock:
2810
2811	__ceph_touch_fmode(ci, mdsc, flags);
2812
2813	spin_unlock(&ci->i_ceph_lock);
2814	if (snap_rwsem_locked)
2815		up_read(&mdsc->snap_rwsem);
2816
2817	if (!ret)
2818		ceph_update_cap_mis(&mdsc->metric);
2819	else if (ret == 1)
2820		ceph_update_cap_hit(&mdsc->metric);
2821
2822	dout("get_cap_refs %p ret %d got %s\n", inode,
2823	     ret, ceph_cap_string(*got));
2824	return ret;
2825}
2826
2827/*
2828 * Check the offset we are writing up to against our current
2829 * max_size.  If necessary, tell the MDS we want to write to
2830 * a larger offset.
2831 */
2832static void check_max_size(struct inode *inode, loff_t endoff)
2833{
2834	struct ceph_inode_info *ci = ceph_inode(inode);
2835	int check = 0;
2836
2837	/* do we need to explicitly request a larger max_size? */
2838	spin_lock(&ci->i_ceph_lock);
2839	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
2840		dout("write %p at large endoff %llu, req max_size\n",
2841		     inode, endoff);
2842		ci->i_wanted_max_size = endoff;
2843	}
2844	/* duplicate ceph_check_caps()'s logic */
2845	if (ci->i_auth_cap &&
2846	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2847	    ci->i_wanted_max_size > ci->i_max_size &&
2848	    ci->i_wanted_max_size > ci->i_requested_max_size)
2849		check = 1;
2850	spin_unlock(&ci->i_ceph_lock);
2851	if (check)
2852		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY);
2853}
2854
2855static inline int get_used_fmode(int caps)
2856{
2857	int fmode = 0;
2858	if (caps & CEPH_CAP_FILE_RD)
2859		fmode |= CEPH_FILE_MODE_RD;
2860	if (caps & CEPH_CAP_FILE_WR)
2861		fmode |= CEPH_FILE_MODE_WR;
2862	return fmode;
2863}
2864
2865int ceph_try_get_caps(struct inode *inode, int need, int want,
2866		      bool nonblock, int *got)
2867{
2868	int ret, flags;
2869
2870	BUG_ON(need & ~CEPH_CAP_FILE_RD);
2871	BUG_ON(want & ~(CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO |
2872			CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL |
2873			CEPH_CAP_ANY_DIR_OPS));
2874	if (need) {
2875		ret = ceph_pool_perm_check(inode, need);
2876		if (ret < 0)
2877			return ret;
2878	}
2879
2880	flags = get_used_fmode(need | want);
2881	if (nonblock)
2882		flags |= NON_BLOCKING;
2883
2884	ret = try_get_cap_refs(inode, need, want, 0, flags, got);
2885	/* three special error codes */
2886	if (ret == -EAGAIN || ret == -EFBIG || ret == -EUCLEAN)
2887		ret = 0;
2888	return ret;
2889}
2890
2891/*
2892 * Wait for caps, and take cap references.  If we can't get a WR cap
2893 * due to a small max_size, make sure we check_max_size (and possibly
2894 * ask the mds) so we don't get hung up indefinitely.
2895 */
2896int ceph_get_caps(struct file *filp, int need, int want, loff_t endoff, int *got)
 
2897{
2898	struct ceph_file_info *fi = filp->private_data;
2899	struct inode *inode = file_inode(filp);
2900	struct ceph_inode_info *ci = ceph_inode(inode);
2901	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
2902	int ret, _got, flags;
2903
2904	ret = ceph_pool_perm_check(inode, need);
2905	if (ret < 0)
2906		return ret;
2907
2908	if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2909	    fi->filp_gen != READ_ONCE(fsc->filp_gen))
2910		return -EBADF;
2911
2912	flags = get_used_fmode(need | want);
2913
2914	while (true) {
2915		flags &= CEPH_FILE_MODE_MASK;
2916		if (vfs_inode_has_locks(inode))
2917			flags |= CHECK_FILELOCK;
2918		_got = 0;
2919		ret = try_get_cap_refs(inode, need, want, endoff,
2920				       flags, &_got);
2921		WARN_ON_ONCE(ret == -EAGAIN);
2922		if (!ret) {
2923			struct ceph_mds_client *mdsc = fsc->mdsc;
2924			struct cap_wait cw;
2925			DEFINE_WAIT_FUNC(wait, woken_wake_function);
2926
2927			cw.ino = ceph_ino(inode);
2928			cw.tgid = current->tgid;
2929			cw.need = need;
2930			cw.want = want;
2931
2932			spin_lock(&mdsc->caps_list_lock);
2933			list_add(&cw.list, &mdsc->cap_wait_list);
2934			spin_unlock(&mdsc->caps_list_lock);
2935
2936			/* make sure used fmode not timeout */
2937			ceph_get_fmode(ci, flags, FMODE_WAIT_BIAS);
2938			add_wait_queue(&ci->i_cap_wq, &wait);
2939
2940			flags |= NON_BLOCKING;
2941			while (!(ret = try_get_cap_refs(inode, need, want,
2942							endoff, flags, &_got))) {
2943				if (signal_pending(current)) {
2944					ret = -ERESTARTSYS;
2945					break;
2946				}
2947				wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2948			}
2949
2950			remove_wait_queue(&ci->i_cap_wq, &wait);
2951			ceph_put_fmode(ci, flags, FMODE_WAIT_BIAS);
2952
2953			spin_lock(&mdsc->caps_list_lock);
2954			list_del(&cw.list);
2955			spin_unlock(&mdsc->caps_list_lock);
2956
2957			if (ret == -EAGAIN)
2958				continue;
2959		}
2960
2961		if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2962		    fi->filp_gen != READ_ONCE(fsc->filp_gen)) {
2963			if (ret >= 0 && _got)
2964				ceph_put_cap_refs(ci, _got);
2965			return -EBADF;
2966		}
2967
2968		if (ret < 0) {
2969			if (ret == -EFBIG || ret == -EUCLEAN) {
2970				int ret2 = ceph_wait_on_async_create(inode);
2971				if (ret2 < 0)
2972					return ret2;
2973			}
2974			if (ret == -EFBIG) {
2975				check_max_size(inode, endoff);
2976				continue;
2977			}
2978			if (ret == -EUCLEAN) {
2979				/* session was killed, try renew caps */
2980				ret = ceph_renew_caps(inode, flags);
2981				if (ret == 0)
2982					continue;
2983			}
2984			return ret;
2985		}
2986
2987		if (S_ISREG(ci->netfs.inode.i_mode) &&
2988		    ceph_has_inline_data(ci) &&
2989		    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
2990		    i_size_read(inode) > 0) {
2991			struct page *page =
2992				find_get_page(inode->i_mapping, 0);
2993			if (page) {
2994				bool uptodate = PageUptodate(page);
2995
2996				put_page(page);
2997				if (uptodate)
2998					break;
2999			}
3000			/*
3001			 * drop cap refs first because getattr while
3002			 * holding * caps refs can cause deadlock.
3003			 */
3004			ceph_put_cap_refs(ci, _got);
3005			_got = 0;
3006
3007			/*
3008			 * getattr request will bring inline data into
3009			 * page cache
3010			 */
3011			ret = __ceph_do_getattr(inode, NULL,
3012						CEPH_STAT_CAP_INLINE_DATA,
3013						true);
3014			if (ret < 0)
3015				return ret;
3016			continue;
3017		}
3018		break;
3019	}
3020	*got = _got;
3021	return 0;
3022}
3023
3024/*
3025 * Take cap refs.  Caller must already know we hold at least one ref
3026 * on the caps in question or we don't know this is safe.
3027 */
3028void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
3029{
3030	spin_lock(&ci->i_ceph_lock);
3031	ceph_take_cap_refs(ci, caps, false);
3032	spin_unlock(&ci->i_ceph_lock);
3033}
3034
3035
3036/*
3037 * drop cap_snap that is not associated with any snapshot.
3038 * we don't need to send FLUSHSNAP message for it.
3039 */
3040static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
3041				  struct ceph_cap_snap *capsnap)
3042{
3043	if (!capsnap->need_flush &&
3044	    !capsnap->writing && !capsnap->dirty_pages) {
3045		dout("dropping cap_snap %p follows %llu\n",
3046		     capsnap, capsnap->follows);
3047		BUG_ON(capsnap->cap_flush.tid > 0);
3048		ceph_put_snap_context(capsnap->context);
3049		if (!list_is_last(&capsnap->ci_item, &ci->i_cap_snaps))
3050			ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
3051
3052		list_del(&capsnap->ci_item);
3053		ceph_put_cap_snap(capsnap);
3054		return 1;
3055	}
3056	return 0;
3057}
3058
3059enum put_cap_refs_mode {
3060	PUT_CAP_REFS_SYNC = 0,
3061	PUT_CAP_REFS_NO_CHECK,
3062	PUT_CAP_REFS_ASYNC,
3063};
3064
3065/*
3066 * Release cap refs.
3067 *
3068 * If we released the last ref on any given cap, call ceph_check_caps
3069 * to release (or schedule a release).
3070 *
3071 * If we are releasing a WR cap (from a sync write), finalize any affected
3072 * cap_snap, and wake up any waiters.
3073 */
3074static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had,
3075				enum put_cap_refs_mode mode)
3076{
3077	struct inode *inode = &ci->netfs.inode;
3078	int last = 0, put = 0, flushsnaps = 0, wake = 0;
3079	bool check_flushsnaps = false;
3080
3081	spin_lock(&ci->i_ceph_lock);
3082	if (had & CEPH_CAP_PIN)
3083		--ci->i_pin_ref;
3084	if (had & CEPH_CAP_FILE_RD)
3085		if (--ci->i_rd_ref == 0)
3086			last++;
3087	if (had & CEPH_CAP_FILE_CACHE)
3088		if (--ci->i_rdcache_ref == 0)
3089			last++;
3090	if (had & CEPH_CAP_FILE_EXCL)
3091		if (--ci->i_fx_ref == 0)
3092			last++;
3093	if (had & CEPH_CAP_FILE_BUFFER) {
3094		if (--ci->i_wb_ref == 0) {
3095			last++;
3096			/* put the ref held by ceph_take_cap_refs() */
3097			put++;
3098			check_flushsnaps = true;
3099		}
3100		dout("put_cap_refs %p wb %d -> %d (?)\n",
3101		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
3102	}
3103	if (had & CEPH_CAP_FILE_WR) {
3104		if (--ci->i_wr_ref == 0) {
3105			last++;
3106			check_flushsnaps = true;
3107			if (ci->i_wrbuffer_ref_head == 0 &&
3108			    ci->i_dirty_caps == 0 &&
3109			    ci->i_flushing_caps == 0) {
3110				BUG_ON(!ci->i_head_snapc);
3111				ceph_put_snap_context(ci->i_head_snapc);
3112				ci->i_head_snapc = NULL;
 
 
 
 
3113			}
3114			/* see comment in __ceph_remove_cap() */
3115			if (!__ceph_is_any_real_caps(ci) && ci->i_snap_realm)
3116				ceph_change_snap_realm(inode, NULL);
3117		}
3118	}
3119	if (check_flushsnaps && __ceph_have_pending_cap_snap(ci)) {
3120		struct ceph_cap_snap *capsnap =
3121			list_last_entry(&ci->i_cap_snaps,
3122					struct ceph_cap_snap,
3123					ci_item);
3124
3125		capsnap->writing = 0;
3126		if (ceph_try_drop_cap_snap(ci, capsnap))
3127			/* put the ref held by ceph_queue_cap_snap() */
3128			put++;
3129		else if (__ceph_finish_cap_snap(ci, capsnap))
3130			flushsnaps = 1;
3131		wake = 1;
3132	}
3133	spin_unlock(&ci->i_ceph_lock);
3134
3135	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
3136	     last ? " last" : "", put ? " put" : "");
3137
3138	switch (mode) {
3139	case PUT_CAP_REFS_SYNC:
3140		if (last)
3141			ceph_check_caps(ci, 0);
3142		else if (flushsnaps)
3143			ceph_flush_snaps(ci, NULL);
3144		break;
3145	case PUT_CAP_REFS_ASYNC:
3146		if (last)
3147			ceph_queue_check_caps(inode);
3148		else if (flushsnaps)
3149			ceph_queue_flush_snaps(inode);
3150		break;
3151	default:
3152		break;
3153	}
3154	if (wake)
3155		wake_up_all(&ci->i_cap_wq);
3156	while (put-- > 0)
3157		iput(inode);
3158}
3159
3160void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
3161{
3162	__ceph_put_cap_refs(ci, had, PUT_CAP_REFS_SYNC);
3163}
3164
3165void ceph_put_cap_refs_async(struct ceph_inode_info *ci, int had)
3166{
3167	__ceph_put_cap_refs(ci, had, PUT_CAP_REFS_ASYNC);
3168}
3169
3170void ceph_put_cap_refs_no_check_caps(struct ceph_inode_info *ci, int had)
3171{
3172	__ceph_put_cap_refs(ci, had, PUT_CAP_REFS_NO_CHECK);
3173}
3174
3175/*
3176 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
3177 * context.  Adjust per-snap dirty page accounting as appropriate.
3178 * Once all dirty data for a cap_snap is flushed, flush snapped file
3179 * metadata back to the MDS.  If we dropped the last ref, call
3180 * ceph_check_caps.
3181 */
3182void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
3183				struct ceph_snap_context *snapc)
3184{
3185	struct inode *inode = &ci->netfs.inode;
3186	struct ceph_cap_snap *capsnap = NULL, *iter;
3187	int put = 0;
3188	bool last = false;
3189	bool flush_snaps = false;
3190	bool complete_capsnap = false;
3191
3192	spin_lock(&ci->i_ceph_lock);
3193	ci->i_wrbuffer_ref -= nr;
3194	if (ci->i_wrbuffer_ref == 0) {
3195		last = true;
3196		put++;
3197	}
3198
3199	if (ci->i_head_snapc == snapc) {
3200		ci->i_wrbuffer_ref_head -= nr;
3201		if (ci->i_wrbuffer_ref_head == 0 &&
3202		    ci->i_wr_ref == 0 &&
3203		    ci->i_dirty_caps == 0 &&
3204		    ci->i_flushing_caps == 0) {
3205			BUG_ON(!ci->i_head_snapc);
3206			ceph_put_snap_context(ci->i_head_snapc);
3207			ci->i_head_snapc = NULL;
3208		}
3209		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
3210		     inode,
3211		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
3212		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
3213		     last ? " LAST" : "");
3214	} else {
3215		list_for_each_entry(iter, &ci->i_cap_snaps, ci_item) {
3216			if (iter->context == snapc) {
3217				capsnap = iter;
3218				break;
3219			}
3220		}
3221
3222		if (!capsnap) {
3223			/*
3224			 * The capsnap should already be removed when removing
3225			 * auth cap in the case of a forced unmount.
3226			 */
3227			WARN_ON_ONCE(ci->i_auth_cap);
3228			goto unlock;
3229		}
3230
3231		capsnap->dirty_pages -= nr;
3232		if (capsnap->dirty_pages == 0) {
3233			complete_capsnap = true;
3234			if (!capsnap->writing) {
3235				if (ceph_try_drop_cap_snap(ci, capsnap)) {
3236					put++;
3237				} else {
3238					ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
3239					flush_snaps = true;
3240				}
3241			}
3242		}
3243		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
3244		     " snap %lld %d/%d -> %d/%d %s%s\n",
3245		     inode, capsnap, capsnap->context->seq,
3246		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
3247		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
3248		     last ? " (wrbuffer last)" : "",
3249		     complete_capsnap ? " (complete capsnap)" : "");
 
 
 
 
 
 
 
3250	}
3251
3252unlock:
3253	spin_unlock(&ci->i_ceph_lock);
3254
3255	if (last) {
3256		ceph_check_caps(ci, 0);
3257	} else if (flush_snaps) {
3258		ceph_flush_snaps(ci, NULL);
 
 
3259	}
3260	if (complete_capsnap)
3261		wake_up_all(&ci->i_cap_wq);
3262	while (put-- > 0) {
3263		iput(inode);
3264	}
3265}
3266
3267/*
3268 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
3269 */
3270static void invalidate_aliases(struct inode *inode)
3271{
3272	struct dentry *dn, *prev = NULL;
3273
3274	dout("invalidate_aliases inode %p\n", inode);
3275	d_prune_aliases(inode);
3276	/*
3277	 * For non-directory inode, d_find_alias() only returns
3278	 * hashed dentry. After calling d_invalidate(), the
3279	 * dentry becomes unhashed.
3280	 *
3281	 * For directory inode, d_find_alias() can return
3282	 * unhashed dentry. But directory inode should have
3283	 * one alias at most.
3284	 */
3285	while ((dn = d_find_alias(inode))) {
3286		if (dn == prev) {
3287			dput(dn);
3288			break;
3289		}
3290		d_invalidate(dn);
3291		if (prev)
3292			dput(prev);
3293		prev = dn;
3294	}
3295	if (prev)
3296		dput(prev);
3297}
3298
3299struct cap_extra_info {
3300	struct ceph_string *pool_ns;
3301	/* inline data */
3302	u64 inline_version;
3303	void *inline_data;
3304	u32 inline_len;
3305	/* dirstat */
3306	bool dirstat_valid;
3307	u64 nfiles;
3308	u64 nsubdirs;
3309	u64 change_attr;
3310	/* currently issued */
3311	int issued;
3312	struct timespec64 btime;
3313};
3314
3315/*
3316 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
3317 * actually be a revocation if it specifies a smaller cap set.)
3318 *
3319 * caller holds s_mutex and i_ceph_lock, we drop both.
 
 
 
 
 
3320 */
3321static void handle_cap_grant(struct inode *inode,
3322			     struct ceph_mds_session *session,
3323			     struct ceph_cap *cap,
3324			     struct ceph_mds_caps *grant,
3325			     struct ceph_buffer *xattr_buf,
3326			     struct cap_extra_info *extra_info)
3327	__releases(ci->i_ceph_lock)
3328	__releases(session->s_mdsc->snap_rwsem)
3329{
3330	struct ceph_inode_info *ci = ceph_inode(inode);
 
3331	int seq = le32_to_cpu(grant->seq);
3332	int newcaps = le32_to_cpu(grant->caps);
3333	int used, wanted, dirty;
3334	u64 size = le64_to_cpu(grant->size);
3335	u64 max_size = le64_to_cpu(grant->max_size);
3336	unsigned char check_caps = 0;
3337	bool was_stale = cap->cap_gen < atomic_read(&session->s_cap_gen);
3338	bool wake = false;
3339	bool writeback = false;
3340	bool queue_trunc = false;
3341	bool queue_invalidate = false;
3342	bool deleted_inode = false;
3343	bool fill_inline = false;
3344
3345	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
3346	     inode, cap, session->s_mds, seq, ceph_cap_string(newcaps));
3347	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
3348		i_size_read(inode));
3349
3350
3351	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3352	 * If CACHE is being revoked, and we have no dirty buffers,
3353	 * try to invalidate (once).  (If there are dirty buffers, we
3354	 * will invalidate _after_ writeback.)
3355	 */
3356	if (S_ISREG(inode->i_mode) && /* don't invalidate readdir cache */
3357	    ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
3358	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3359	    !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
3360		if (try_nonblocking_invalidate(inode)) {
3361			/* there were locked pages.. invalidate later
3362			   in a separate thread. */
3363			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
3364				queue_invalidate = true;
3365				ci->i_rdcache_revoking = ci->i_rdcache_gen;
3366			}
3367		}
 
 
3368	}
3369
3370	if (was_stale)
3371		cap->issued = cap->implemented = CEPH_CAP_PIN;
3372
3373	/*
3374	 * auth mds of the inode changed. we received the cap export message,
3375	 * but still haven't received the cap import message. handle_cap_export
3376	 * updated the new auth MDS' cap.
3377	 *
3378	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
3379	 * that was sent before the cap import message. So don't remove caps.
3380	 */
3381	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
3382		WARN_ON(cap != ci->i_auth_cap);
3383		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
3384		seq = cap->seq;
3385		newcaps |= cap->issued;
3386	}
3387
3388	/* side effects now are allowed */
3389	cap->cap_gen = atomic_read(&session->s_cap_gen);
3390	cap->seq = seq;
3391
3392	__check_cap_issue(ci, cap, newcaps);
3393
3394	inode_set_max_iversion_raw(inode, extra_info->change_attr);
3395
3396	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
3397	    (extra_info->issued & CEPH_CAP_AUTH_EXCL) == 0) {
3398		umode_t mode = le32_to_cpu(grant->mode);
3399
3400		if (inode_wrong_type(inode, mode))
3401			pr_warn_once("inode type changed! (ino %llx.%llx is 0%o, mds says 0%o)\n",
3402				     ceph_vinop(inode), inode->i_mode, mode);
3403		else
3404			inode->i_mode = mode;
3405		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
3406		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
3407		ci->i_btime = extra_info->btime;
3408		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
3409		     from_kuid(&init_user_ns, inode->i_uid),
3410		     from_kgid(&init_user_ns, inode->i_gid));
3411	}
3412
3413	if ((newcaps & CEPH_CAP_LINK_SHARED) &&
3414	    (extra_info->issued & CEPH_CAP_LINK_EXCL) == 0) {
3415		set_nlink(inode, le32_to_cpu(grant->nlink));
3416		if (inode->i_nlink == 0)
3417			deleted_inode = true;
 
3418	}
3419
3420	if ((extra_info->issued & CEPH_CAP_XATTR_EXCL) == 0 &&
3421	    grant->xattr_len) {
3422		int len = le32_to_cpu(grant->xattr_len);
3423		u64 version = le64_to_cpu(grant->xattr_version);
3424
3425		if (version > ci->i_xattrs.version) {
3426			dout(" got new xattrs v%llu on %p len %d\n",
3427			     version, inode, len);
3428			if (ci->i_xattrs.blob)
3429				ceph_buffer_put(ci->i_xattrs.blob);
3430			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
3431			ci->i_xattrs.version = version;
3432			ceph_forget_all_cached_acls(inode);
3433			ceph_security_invalidate_secctx(inode);
3434		}
3435	}
3436
3437	if (newcaps & CEPH_CAP_ANY_RD) {
3438		struct timespec64 mtime, atime, ctime;
3439		/* ctime/mtime/atime? */
3440		ceph_decode_timespec64(&mtime, &grant->mtime);
3441		ceph_decode_timespec64(&atime, &grant->atime);
3442		ceph_decode_timespec64(&ctime, &grant->ctime);
3443		ceph_fill_file_time(inode, extra_info->issued,
3444				    le32_to_cpu(grant->time_warp_seq),
3445				    &ctime, &mtime, &atime);
3446	}
3447
3448	if ((newcaps & CEPH_CAP_FILE_SHARED) && extra_info->dirstat_valid) {
3449		ci->i_files = extra_info->nfiles;
3450		ci->i_subdirs = extra_info->nsubdirs;
3451	}
3452
3453	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
3454		/* file layout may have changed */
3455		s64 old_pool = ci->i_layout.pool_id;
3456		struct ceph_string *old_ns;
3457
3458		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
3459		old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
3460					lockdep_is_held(&ci->i_ceph_lock));
3461		rcu_assign_pointer(ci->i_layout.pool_ns, extra_info->pool_ns);
3462
3463		if (ci->i_layout.pool_id != old_pool ||
3464		    extra_info->pool_ns != old_ns)
3465			ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
3466
3467		extra_info->pool_ns = old_ns;
3468
3469		/* size/truncate_seq? */
3470		queue_trunc = ceph_fill_file_size(inode, extra_info->issued,
3471					le32_to_cpu(grant->truncate_seq),
3472					le64_to_cpu(grant->truncate_size),
3473					size);
3474	}
3475
3476	if (ci->i_auth_cap == cap && (newcaps & CEPH_CAP_ANY_FILE_WR)) {
3477		if (max_size != ci->i_max_size) {
3478			dout("max_size %lld -> %llu\n",
3479			     ci->i_max_size, max_size);
3480			ci->i_max_size = max_size;
3481			if (max_size >= ci->i_wanted_max_size) {
3482				ci->i_wanted_max_size = 0;  /* reset */
3483				ci->i_requested_max_size = 0;
3484			}
3485			wake = true;
3486		}
 
3487	}
3488
3489	/* check cap bits */
3490	wanted = __ceph_caps_wanted(ci);
3491	used = __ceph_caps_used(ci);
3492	dirty = __ceph_caps_dirty(ci);
3493	dout(" my wanted = %s, used = %s, dirty %s\n",
3494	     ceph_cap_string(wanted),
3495	     ceph_cap_string(used),
3496	     ceph_cap_string(dirty));
3497
3498	if ((was_stale || le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) &&
3499	    (wanted & ~(cap->mds_wanted | newcaps))) {
3500		/*
3501		 * If mds is importing cap, prior cap messages that update
3502		 * 'wanted' may get dropped by mds (migrate seq mismatch).
3503		 *
3504		 * We don't send cap message to update 'wanted' if what we
3505		 * want are already issued. If mds revokes caps, cap message
3506		 * that releases caps also tells mds what we want. But if
3507		 * caps got revoked by mds forcedly (session stale). We may
3508		 * haven't told mds what we want.
3509		 */
3510		check_caps = 1;
3511	}
3512
3513	/* revocation, grant, or no-op? */
3514	if (cap->issued & ~newcaps) {
3515		int revoking = cap->issued & ~newcaps;
3516
3517		dout("revocation: %s -> %s (revoking %s)\n",
3518		     ceph_cap_string(cap->issued),
3519		     ceph_cap_string(newcaps),
3520		     ceph_cap_string(revoking));
3521		if (S_ISREG(inode->i_mode) &&
3522		    (revoking & used & CEPH_CAP_FILE_BUFFER))
3523			writeback = true;  /* initiate writeback; will delay ack */
3524		else if (queue_invalidate &&
3525			 revoking == CEPH_CAP_FILE_CACHE &&
3526			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0)
3527			; /* do nothing yet, invalidation will be queued */
3528		else if (cap == ci->i_auth_cap)
3529			check_caps = 1; /* check auth cap only */
3530		else
3531			check_caps = 2; /* check all caps */
3532		/* If there is new caps, try to wake up the waiters */
3533		if (~cap->issued & newcaps)
3534			wake = true;
3535		cap->issued = newcaps;
3536		cap->implemented |= newcaps;
3537	} else if (cap->issued == newcaps) {
3538		dout("caps unchanged: %s -> %s\n",
3539		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
3540	} else {
3541		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
3542		     ceph_cap_string(newcaps));
3543		/* non-auth MDS is revoking the newly grant caps ? */
3544		if (cap == ci->i_auth_cap &&
3545		    __ceph_caps_revoking_other(ci, cap, newcaps))
3546		    check_caps = 2;
3547
3548		cap->issued = newcaps;
3549		cap->implemented |= newcaps; /* add bits only, to
3550					      * avoid stepping on a
3551					      * pending revocation */
3552		wake = true;
3553	}
3554	BUG_ON(cap->issued & ~cap->implemented);
3555
3556	if (extra_info->inline_version > 0 &&
3557	    extra_info->inline_version >= ci->i_inline_version) {
3558		ci->i_inline_version = extra_info->inline_version;
3559		if (ci->i_inline_version != CEPH_INLINE_NONE &&
3560		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
3561			fill_inline = true;
3562	}
3563
3564	if (le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
3565		if (ci->i_auth_cap == cap) {
3566			if (newcaps & ~extra_info->issued)
3567				wake = true;
3568
3569			if (ci->i_requested_max_size > max_size ||
3570			    !(le32_to_cpu(grant->wanted) & CEPH_CAP_ANY_FILE_WR)) {
3571				/* re-request max_size if necessary */
3572				ci->i_requested_max_size = 0;
3573				wake = true;
3574			}
3575
3576			ceph_kick_flushing_inode_caps(session, ci);
3577		}
3578		up_read(&session->s_mdsc->snap_rwsem);
3579	}
3580	spin_unlock(&ci->i_ceph_lock);
3581
3582	if (fill_inline)
3583		ceph_fill_inline_data(inode, NULL, extra_info->inline_data,
3584				      extra_info->inline_len);
3585
3586	if (queue_trunc)
3587		ceph_queue_vmtruncate(inode);
3588
3589	if (writeback)
3590		/*
3591		 * queue inode for writeback: we can't actually call
3592		 * filemap_write_and_wait, etc. from message handler
3593		 * context.
3594		 */
3595		ceph_queue_writeback(inode);
3596	if (queue_invalidate)
3597		ceph_queue_invalidate(inode);
3598	if (deleted_inode)
3599		invalidate_aliases(inode);
 
 
3600	if (wake)
3601		wake_up_all(&ci->i_cap_wq);
3602
3603	mutex_unlock(&session->s_mutex);
3604	if (check_caps == 1)
3605		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY | CHECK_CAPS_NOINVAL);
 
3606	else if (check_caps == 2)
3607		ceph_check_caps(ci, CHECK_CAPS_NOINVAL);
 
 
3608}
3609
3610/*
3611 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
3612 * MDS has been safely committed.
3613 */
3614static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
3615				 struct ceph_mds_caps *m,
3616				 struct ceph_mds_session *session,
3617				 struct ceph_cap *cap)
3618	__releases(ci->i_ceph_lock)
3619{
3620	struct ceph_inode_info *ci = ceph_inode(inode);
3621	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3622	struct ceph_cap_flush *cf, *tmp_cf;
3623	LIST_HEAD(to_remove);
3624	unsigned seq = le32_to_cpu(m->seq);
3625	int dirty = le32_to_cpu(m->dirty);
3626	int cleaned = 0;
3627	bool drop = false;
3628	bool wake_ci = false;
3629	bool wake_mdsc = false;
3630
3631	list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) {
3632		/* Is this the one that was flushed? */
3633		if (cf->tid == flush_tid)
3634			cleaned = cf->caps;
3635
3636		/* Is this a capsnap? */
3637		if (cf->is_capsnap)
3638			continue;
3639
3640		if (cf->tid <= flush_tid) {
3641			/*
3642			 * An earlier or current tid. The FLUSH_ACK should
3643			 * represent a superset of this flush's caps.
3644			 */
3645			wake_ci |= __detach_cap_flush_from_ci(ci, cf);
3646			list_add_tail(&cf->i_list, &to_remove);
3647		} else {
3648			/*
3649			 * This is a later one. Any caps in it are still dirty
3650			 * so don't count them as cleaned.
3651			 */
3652			cleaned &= ~cf->caps;
3653			if (!cleaned)
3654				break;
3655		}
3656	}
3657
3658	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
3659	     " flushing %s -> %s\n",
3660	     inode, session->s_mds, seq, ceph_cap_string(dirty),
3661	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
3662	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
3663
3664	if (list_empty(&to_remove) && !cleaned)
3665		goto out;
3666
3667	ci->i_flushing_caps &= ~cleaned;
3668
3669	spin_lock(&mdsc->cap_dirty_lock);
3670
3671	list_for_each_entry(cf, &to_remove, i_list)
3672		wake_mdsc |= __detach_cap_flush_from_mdsc(mdsc, cf);
3673
3674	if (ci->i_flushing_caps == 0) {
3675		if (list_empty(&ci->i_cap_flush_list)) {
3676			list_del_init(&ci->i_flushing_item);
3677			if (!list_empty(&session->s_cap_flushing)) {
3678				dout(" mds%d still flushing cap on %p\n",
3679				     session->s_mds,
3680				     &list_first_entry(&session->s_cap_flushing,
3681						struct ceph_inode_info,
3682						i_flushing_item)->netfs.inode);
3683			}
3684		}
3685		mdsc->num_cap_flushing--;
 
3686		dout(" inode %p now !flushing\n", inode);
3687
3688		if (ci->i_dirty_caps == 0) {
3689			dout(" inode %p now clean\n", inode);
3690			BUG_ON(!list_empty(&ci->i_dirty_item));
3691			drop = true;
3692			if (ci->i_wr_ref == 0 &&
3693			    ci->i_wrbuffer_ref_head == 0) {
3694				BUG_ON(!ci->i_head_snapc);
3695				ceph_put_snap_context(ci->i_head_snapc);
3696				ci->i_head_snapc = NULL;
3697			}
3698		} else {
3699			BUG_ON(list_empty(&ci->i_dirty_item));
3700		}
3701	}
3702	spin_unlock(&mdsc->cap_dirty_lock);
 
3703
3704out:
3705	spin_unlock(&ci->i_ceph_lock);
3706
3707	while (!list_empty(&to_remove)) {
3708		cf = list_first_entry(&to_remove,
3709				      struct ceph_cap_flush, i_list);
3710		list_del_init(&cf->i_list);
3711		if (!cf->is_capsnap)
3712			ceph_free_cap_flush(cf);
3713	}
3714
3715	if (wake_ci)
3716		wake_up_all(&ci->i_cap_wq);
3717	if (wake_mdsc)
3718		wake_up_all(&mdsc->cap_flushing_wq);
3719	if (drop)
3720		iput(inode);
3721}
3722
3723void __ceph_remove_capsnap(struct inode *inode, struct ceph_cap_snap *capsnap,
3724			   bool *wake_ci, bool *wake_mdsc)
3725{
3726	struct ceph_inode_info *ci = ceph_inode(inode);
3727	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3728	bool ret;
3729
3730	lockdep_assert_held(&ci->i_ceph_lock);
3731
3732	dout("removing capsnap %p, inode %p ci %p\n", capsnap, inode, ci);
3733
3734	list_del_init(&capsnap->ci_item);
3735	ret = __detach_cap_flush_from_ci(ci, &capsnap->cap_flush);
3736	if (wake_ci)
3737		*wake_ci = ret;
3738
3739	spin_lock(&mdsc->cap_dirty_lock);
3740	if (list_empty(&ci->i_cap_flush_list))
3741		list_del_init(&ci->i_flushing_item);
3742
3743	ret = __detach_cap_flush_from_mdsc(mdsc, &capsnap->cap_flush);
3744	if (wake_mdsc)
3745		*wake_mdsc = ret;
3746	spin_unlock(&mdsc->cap_dirty_lock);
3747}
3748
3749void ceph_remove_capsnap(struct inode *inode, struct ceph_cap_snap *capsnap,
3750			 bool *wake_ci, bool *wake_mdsc)
3751{
3752	struct ceph_inode_info *ci = ceph_inode(inode);
3753
3754	lockdep_assert_held(&ci->i_ceph_lock);
3755
3756	WARN_ON_ONCE(capsnap->dirty_pages || capsnap->writing);
3757	__ceph_remove_capsnap(inode, capsnap, wake_ci, wake_mdsc);
3758}
3759
3760/*
3761 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
3762 * throw away our cap_snap.
3763 *
3764 * Caller hold s_mutex.
3765 */
3766static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
3767				     struct ceph_mds_caps *m,
3768				     struct ceph_mds_session *session)
3769{
3770	struct ceph_inode_info *ci = ceph_inode(inode);
3771	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3772	u64 follows = le64_to_cpu(m->snap_follows);
3773	struct ceph_cap_snap *capsnap = NULL, *iter;
3774	bool wake_ci = false;
3775	bool wake_mdsc = false;
3776
3777	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
3778	     inode, ci, session->s_mds, follows);
3779
3780	spin_lock(&ci->i_ceph_lock);
3781	list_for_each_entry(iter, &ci->i_cap_snaps, ci_item) {
3782		if (iter->follows == follows) {
3783			if (iter->cap_flush.tid != flush_tid) {
3784				dout(" cap_snap %p follows %lld tid %lld !="
3785				     " %lld\n", iter, follows,
3786				     flush_tid, iter->cap_flush.tid);
3787				break;
3788			}
3789			capsnap = iter;
 
 
 
 
 
 
 
3790			break;
3791		} else {
3792			dout(" skipping cap_snap %p follows %lld\n",
3793			     iter, iter->follows);
3794		}
3795	}
3796	if (capsnap)
3797		ceph_remove_capsnap(inode, capsnap, &wake_ci, &wake_mdsc);
3798	spin_unlock(&ci->i_ceph_lock);
3799
3800	if (capsnap) {
3801		ceph_put_snap_context(capsnap->context);
3802		ceph_put_cap_snap(capsnap);
3803		if (wake_ci)
3804			wake_up_all(&ci->i_cap_wq);
3805		if (wake_mdsc)
3806			wake_up_all(&mdsc->cap_flushing_wq);
3807		iput(inode);
3808	}
3809}
3810
3811/*
3812 * Handle TRUNC from MDS, indicating file truncation.
3813 *
3814 * caller hold s_mutex.
3815 */
3816static bool handle_cap_trunc(struct inode *inode,
3817			     struct ceph_mds_caps *trunc,
3818			     struct ceph_mds_session *session)
 
3819{
3820	struct ceph_inode_info *ci = ceph_inode(inode);
3821	int mds = session->s_mds;
3822	int seq = le32_to_cpu(trunc->seq);
3823	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
3824	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
3825	u64 size = le64_to_cpu(trunc->size);
3826	int implemented = 0;
3827	int dirty = __ceph_caps_dirty(ci);
3828	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
3829	bool queue_trunc = false;
3830
3831	lockdep_assert_held(&ci->i_ceph_lock);
3832
3833	issued |= implemented | dirty;
3834
3835	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
3836	     inode, mds, seq, truncate_size, truncate_seq);
3837	queue_trunc = ceph_fill_file_size(inode, issued,
3838					  truncate_seq, truncate_size, size);
3839	return queue_trunc;
 
 
 
 
 
3840}
3841
3842/*
3843 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
3844 * different one.  If we are the most recent migration we've seen (as
3845 * indicated by mseq), make note of the migrating cap bits for the
3846 * duration (until we see the corresponding IMPORT).
3847 *
3848 * caller holds s_mutex
3849 */
3850static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
3851			      struct ceph_mds_cap_peer *ph,
3852			      struct ceph_mds_session *session)
3853{
3854	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
3855	struct ceph_mds_session *tsession = NULL;
3856	struct ceph_cap *cap, *tcap, *new_cap = NULL;
3857	struct ceph_inode_info *ci = ceph_inode(inode);
3858	u64 t_cap_id;
3859	unsigned mseq = le32_to_cpu(ex->migrate_seq);
3860	unsigned t_seq, t_mseq;
3861	int target, issued;
3862	int mds = session->s_mds;
3863
3864	if (ph) {
3865		t_cap_id = le64_to_cpu(ph->cap_id);
3866		t_seq = le32_to_cpu(ph->seq);
3867		t_mseq = le32_to_cpu(ph->mseq);
3868		target = le32_to_cpu(ph->mds);
3869	} else {
3870		t_cap_id = t_seq = t_mseq = 0;
3871		target = -1;
3872	}
3873
3874	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
3875	     inode, ci, mds, mseq, target);
3876retry:
3877	down_read(&mdsc->snap_rwsem);
3878	spin_lock(&ci->i_ceph_lock);
3879	cap = __get_cap_for_mds(ci, mds);
3880	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
3881		goto out_unlock;
3882
3883	if (target < 0) {
3884		ceph_remove_cap(cap, false);
3885		goto out_unlock;
3886	}
3887
3888	/*
3889	 * now we know we haven't received the cap import message yet
3890	 * because the exported cap still exist.
3891	 */
3892
3893	issued = cap->issued;
3894	if (issued != cap->implemented)
3895		pr_err_ratelimited("handle_cap_export: issued != implemented: "
3896				"ino (%llx.%llx) mds%d seq %d mseq %d "
3897				"issued %s implemented %s\n",
3898				ceph_vinop(inode), mds, cap->seq, cap->mseq,
3899				ceph_cap_string(issued),
3900				ceph_cap_string(cap->implemented));
3901
3902
3903	tcap = __get_cap_for_mds(ci, target);
3904	if (tcap) {
3905		/* already have caps from the target */
3906		if (tcap->cap_id == t_cap_id &&
3907		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
3908			dout(" updating import cap %p mds%d\n", tcap, target);
3909			tcap->cap_id = t_cap_id;
3910			tcap->seq = t_seq - 1;
3911			tcap->issue_seq = t_seq - 1;
 
3912			tcap->issued |= issued;
3913			tcap->implemented |= issued;
3914			if (cap == ci->i_auth_cap) {
3915				ci->i_auth_cap = tcap;
3916				change_auth_cap_ses(ci, tcap->session);
 
 
 
 
3917			}
3918		}
3919		ceph_remove_cap(cap, false);
3920		goto out_unlock;
3921	} else if (tsession) {
 
 
 
 
3922		/* add placeholder for the export tagert */
3923		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
3924		tcap = new_cap;
3925		ceph_add_cap(inode, tsession, t_cap_id, issued, 0,
3926			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
3927
3928		if (!list_empty(&ci->i_cap_flush_list) &&
3929		    ci->i_auth_cap == tcap) {
3930			spin_lock(&mdsc->cap_dirty_lock);
3931			list_move_tail(&ci->i_flushing_item,
3932				       &tcap->session->s_cap_flushing);
3933			spin_unlock(&mdsc->cap_dirty_lock);
3934		}
3935
3936		ceph_remove_cap(cap, false);
3937		goto out_unlock;
3938	}
3939
3940	spin_unlock(&ci->i_ceph_lock);
3941	up_read(&mdsc->snap_rwsem);
3942	mutex_unlock(&session->s_mutex);
3943
3944	/* open target session */
3945	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
3946	if (!IS_ERR(tsession)) {
3947		if (mds > target) {
3948			mutex_lock(&session->s_mutex);
3949			mutex_lock_nested(&tsession->s_mutex,
3950					  SINGLE_DEPTH_NESTING);
3951		} else {
3952			mutex_lock(&tsession->s_mutex);
3953			mutex_lock_nested(&session->s_mutex,
3954					  SINGLE_DEPTH_NESTING);
3955		}
3956		new_cap = ceph_get_cap(mdsc, NULL);
3957	} else {
3958		WARN_ON(1);
3959		tsession = NULL;
3960		target = -1;
3961		mutex_lock(&session->s_mutex);
3962	}
3963	goto retry;
3964
3965out_unlock:
3966	spin_unlock(&ci->i_ceph_lock);
3967	up_read(&mdsc->snap_rwsem);
3968	mutex_unlock(&session->s_mutex);
3969	if (tsession) {
3970		mutex_unlock(&tsession->s_mutex);
3971		ceph_put_mds_session(tsession);
3972	}
3973	if (new_cap)
3974		ceph_put_cap(mdsc, new_cap);
3975}
3976
3977/*
3978 * Handle cap IMPORT.
 
3979 *
3980 * caller holds s_mutex. acquires i_ceph_lock
3981 */
3982static void handle_cap_import(struct ceph_mds_client *mdsc,
3983			      struct inode *inode, struct ceph_mds_caps *im,
3984			      struct ceph_mds_cap_peer *ph,
3985			      struct ceph_mds_session *session,
3986			      struct ceph_cap **target_cap, int *old_issued)
3987{
3988	struct ceph_inode_info *ci = ceph_inode(inode);
3989	struct ceph_cap *cap, *ocap, *new_cap = NULL;
3990	int mds = session->s_mds;
3991	int issued;
3992	unsigned caps = le32_to_cpu(im->caps);
3993	unsigned wanted = le32_to_cpu(im->wanted);
3994	unsigned seq = le32_to_cpu(im->seq);
3995	unsigned mseq = le32_to_cpu(im->migrate_seq);
3996	u64 realmino = le64_to_cpu(im->realm);
3997	u64 cap_id = le64_to_cpu(im->cap_id);
3998	u64 p_cap_id;
3999	int peer;
4000
4001	if (ph) {
4002		p_cap_id = le64_to_cpu(ph->cap_id);
4003		peer = le32_to_cpu(ph->mds);
4004	} else {
4005		p_cap_id = 0;
4006		peer = -1;
4007	}
4008
4009	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
4010	     inode, ci, mds, mseq, peer);
4011retry:
4012	cap = __get_cap_for_mds(ci, mds);
4013	if (!cap) {
4014		if (!new_cap) {
4015			spin_unlock(&ci->i_ceph_lock);
4016			new_cap = ceph_get_cap(mdsc, NULL);
4017			spin_lock(&ci->i_ceph_lock);
4018			goto retry;
4019		}
4020		cap = new_cap;
4021	} else {
4022		if (new_cap) {
4023			ceph_put_cap(mdsc, new_cap);
4024			new_cap = NULL;
4025		}
4026	}
4027
4028	__ceph_caps_issued(ci, &issued);
4029	issued |= __ceph_caps_dirty(ci);
4030
4031	ceph_add_cap(inode, session, cap_id, caps, wanted, seq, mseq,
4032		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
4033
4034	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
4035	if (ocap && ocap->cap_id == p_cap_id) {
4036		dout(" remove export cap %p mds%d flags %d\n",
4037		     ocap, peer, ph->flags);
4038		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
4039		    (ocap->seq != le32_to_cpu(ph->seq) ||
4040		     ocap->mseq != le32_to_cpu(ph->mseq))) {
4041			pr_err_ratelimited("handle_cap_import: "
4042					"mismatched seq/mseq: ino (%llx.%llx) "
4043					"mds%d seq %d mseq %d importer mds%d "
4044					"has peer seq %d mseq %d\n",
4045					ceph_vinop(inode), peer, ocap->seq,
4046					ocap->mseq, mds, le32_to_cpu(ph->seq),
4047					le32_to_cpu(ph->mseq));
4048		}
4049		ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
4050	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4051
4052	*old_issued = issued;
4053	*target_cap = cap;
4054}
4055
4056/*
4057 * Handle a caps message from the MDS.
4058 *
4059 * Identify the appropriate session, inode, and call the right handler
4060 * based on the cap op.
4061 */
4062void ceph_handle_caps(struct ceph_mds_session *session,
4063		      struct ceph_msg *msg)
4064{
4065	struct ceph_mds_client *mdsc = session->s_mdsc;
 
4066	struct inode *inode;
4067	struct ceph_inode_info *ci;
4068	struct ceph_cap *cap;
4069	struct ceph_mds_caps *h;
4070	struct ceph_mds_cap_peer *peer = NULL;
4071	struct ceph_snap_realm *realm = NULL;
4072	int op;
4073	int msg_version = le16_to_cpu(msg->hdr.version);
4074	u32 seq, mseq;
4075	struct ceph_vino vino;
 
 
 
4076	void *snaptrace;
4077	size_t snaptrace_len;
4078	void *p, *end;
4079	struct cap_extra_info extra_info = {};
4080	bool queue_trunc;
4081	bool close_sessions = false;
4082
4083	dout("handle_caps from mds%d\n", session->s_mds);
4084
4085	/* decode */
4086	end = msg->front.iov_base + msg->front.iov_len;
 
4087	if (msg->front.iov_len < sizeof(*h))
4088		goto bad;
4089	h = msg->front.iov_base;
4090	op = le32_to_cpu(h->op);
4091	vino.ino = le64_to_cpu(h->ino);
4092	vino.snap = CEPH_NOSNAP;
 
4093	seq = le32_to_cpu(h->seq);
4094	mseq = le32_to_cpu(h->migrate_seq);
 
 
4095
4096	snaptrace = h + 1;
4097	snaptrace_len = le32_to_cpu(h->snap_trace_len);
4098	p = snaptrace + snaptrace_len;
4099
4100	if (msg_version >= 2) {
4101		u32 flock_len;
4102		ceph_decode_32_safe(&p, end, flock_len, bad);
4103		if (p + flock_len > end)
4104			goto bad;
4105		p += flock_len;
 
 
 
4106	}
4107
4108	if (msg_version >= 3) {
4109		if (op == CEPH_CAP_OP_IMPORT) {
 
4110			if (p + sizeof(*peer) > end)
4111				goto bad;
4112			peer = p;
4113			p += sizeof(*peer);
4114		} else if (op == CEPH_CAP_OP_EXPORT) {
4115			/* recorded in unused fields */
4116			peer = (void *)&h->size;
4117		}
4118	}
4119
4120	if (msg_version >= 4) {
4121		ceph_decode_64_safe(&p, end, extra_info.inline_version, bad);
4122		ceph_decode_32_safe(&p, end, extra_info.inline_len, bad);
4123		if (p + extra_info.inline_len > end)
4124			goto bad;
4125		extra_info.inline_data = p;
4126		p += extra_info.inline_len;
4127	}
4128
4129	if (msg_version >= 5) {
4130		struct ceph_osd_client	*osdc = &mdsc->fsc->client->osdc;
4131		u32			epoch_barrier;
4132
4133		ceph_decode_32_safe(&p, end, epoch_barrier, bad);
4134		ceph_osdc_update_epoch_barrier(osdc, epoch_barrier);
4135	}
4136
4137	if (msg_version >= 8) {
4138		u32 pool_ns_len;
4139
4140		/* version >= 6 */
4141		ceph_decode_skip_64(&p, end, bad);	// flush_tid
4142		/* version >= 7 */
4143		ceph_decode_skip_32(&p, end, bad);	// caller_uid
4144		ceph_decode_skip_32(&p, end, bad);	// caller_gid
4145		/* version >= 8 */
4146		ceph_decode_32_safe(&p, end, pool_ns_len, bad);
4147		if (pool_ns_len > 0) {
4148			ceph_decode_need(&p, end, pool_ns_len, bad);
4149			extra_info.pool_ns =
4150				ceph_find_or_create_string(p, pool_ns_len);
4151			p += pool_ns_len;
4152		}
4153	}
4154
4155	if (msg_version >= 9) {
4156		struct ceph_timespec *btime;
4157
4158		if (p + sizeof(*btime) > end)
4159			goto bad;
4160		btime = p;
4161		ceph_decode_timespec64(&extra_info.btime, btime);
4162		p += sizeof(*btime);
4163		ceph_decode_64_safe(&p, end, extra_info.change_attr, bad);
4164	}
4165
4166	if (msg_version >= 11) {
4167		/* version >= 10 */
4168		ceph_decode_skip_32(&p, end, bad); // flags
4169		/* version >= 11 */
4170		extra_info.dirstat_valid = true;
4171		ceph_decode_64_safe(&p, end, extra_info.nfiles, bad);
4172		ceph_decode_64_safe(&p, end, extra_info.nsubdirs, bad);
4173	}
4174
4175	/* lookup ino */
4176	inode = ceph_find_inode(mdsc->fsc->sb, vino);
 
4177	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
4178	     vino.snap, inode);
4179
4180	mutex_lock(&session->s_mutex);
4181	inc_session_sequence(session);
4182	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
4183	     (unsigned)seq);
4184
4185	if (!inode) {
4186		dout(" i don't have ino %llx\n", vino.ino);
4187
4188		if (op == CEPH_CAP_OP_IMPORT) {
4189			cap = ceph_get_cap(mdsc, NULL);
4190			cap->cap_ino = vino.ino;
4191			cap->queue_release = 1;
4192			cap->cap_id = le64_to_cpu(h->cap_id);
4193			cap->mseq = mseq;
4194			cap->seq = seq;
4195			cap->issue_seq = seq;
4196			spin_lock(&session->s_cap_lock);
4197			__ceph_queue_cap_release(session, cap);
 
4198			spin_unlock(&session->s_cap_lock);
4199		}
4200		goto flush_cap_releases;
4201	}
4202	ci = ceph_inode(inode);
4203
4204	/* these will work even if we don't have a cap yet */
4205	switch (op) {
4206	case CEPH_CAP_OP_FLUSHSNAP_ACK:
4207		handle_cap_flushsnap_ack(inode, le64_to_cpu(msg->hdr.tid),
4208					 h, session);
4209		goto done;
4210
4211	case CEPH_CAP_OP_EXPORT:
4212		handle_cap_export(inode, h, peer, session);
4213		goto done_unlocked;
4214
4215	case CEPH_CAP_OP_IMPORT:
4216		realm = NULL;
4217		if (snaptrace_len) {
4218			down_write(&mdsc->snap_rwsem);
4219			if (ceph_update_snap_trace(mdsc, snaptrace,
4220						   snaptrace + snaptrace_len,
4221						   false, &realm)) {
4222				up_write(&mdsc->snap_rwsem);
4223				close_sessions = true;
4224				goto done;
4225			}
4226			downgrade_write(&mdsc->snap_rwsem);
4227		} else {
4228			down_read(&mdsc->snap_rwsem);
4229		}
4230		spin_lock(&ci->i_ceph_lock);
4231		handle_cap_import(mdsc, inode, h, peer, session,
4232				  &cap, &extra_info.issued);
4233		handle_cap_grant(inode, session, cap,
4234				 h, msg->middle, &extra_info);
4235		if (realm)
4236			ceph_put_snap_realm(mdsc, realm);
4237		goto done_unlocked;
4238	}
4239
4240	/* the rest require a cap */
4241	spin_lock(&ci->i_ceph_lock);
4242	cap = __get_cap_for_mds(ceph_inode(inode), session->s_mds);
4243	if (!cap) {
4244		dout(" no cap on %p ino %llx.%llx from mds%d\n",
4245		     inode, ceph_ino(inode), ceph_snap(inode),
4246		     session->s_mds);
4247		spin_unlock(&ci->i_ceph_lock);
4248		goto flush_cap_releases;
4249	}
4250
4251	/* note that each of these drops i_ceph_lock for us */
4252	switch (op) {
4253	case CEPH_CAP_OP_REVOKE:
4254	case CEPH_CAP_OP_GRANT:
4255		__ceph_caps_issued(ci, &extra_info.issued);
4256		extra_info.issued |= __ceph_caps_dirty(ci);
4257		handle_cap_grant(inode, session, cap,
4258				 h, msg->middle, &extra_info);
4259		goto done_unlocked;
4260
4261	case CEPH_CAP_OP_FLUSH_ACK:
4262		handle_cap_flush_ack(inode, le64_to_cpu(msg->hdr.tid),
4263				     h, session, cap);
4264		break;
4265
4266	case CEPH_CAP_OP_TRUNC:
4267		queue_trunc = handle_cap_trunc(inode, h, session);
4268		spin_unlock(&ci->i_ceph_lock);
4269		if (queue_trunc)
4270			ceph_queue_vmtruncate(inode);
4271		break;
4272
4273	default:
4274		spin_unlock(&ci->i_ceph_lock);
4275		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
4276		       ceph_cap_op_name(op));
4277	}
4278
4279done:
4280	mutex_unlock(&session->s_mutex);
4281done_unlocked:
4282	iput(inode);
4283out:
4284	ceph_put_string(extra_info.pool_ns);
4285
4286	/* Defer closing the sessions after s_mutex lock being released */
4287	if (close_sessions)
4288		ceph_mdsc_close_sessions(mdsc);
4289
4290	return;
4291
4292flush_cap_releases:
4293	/*
4294	 * send any cap release message to try to move things
4295	 * along for the mds (who clearly thinks we still have this
4296	 * cap).
4297	 */
4298	ceph_flush_cap_releases(mdsc, session);
4299	goto done;
 
 
 
 
 
 
 
4300
4301bad:
4302	pr_err("ceph_handle_caps: corrupt message\n");
4303	ceph_msg_dump(msg);
4304	goto out;
4305}
4306
4307/*
4308 * Delayed work handler to process end of delayed cap release LRU list.
4309 *
4310 * If new caps are added to the list while processing it, these won't get
4311 * processed in this run.  In this case, the ci->i_hold_caps_max will be
4312 * returned so that the work can be scheduled accordingly.
4313 */
4314unsigned long ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
4315{
4316	struct inode *inode;
4317	struct ceph_inode_info *ci;
4318	struct ceph_mount_options *opt = mdsc->fsc->mount_options;
4319	unsigned long delay_max = opt->caps_wanted_delay_max * HZ;
4320	unsigned long loop_start = jiffies;
4321	unsigned long delay = 0;
4322
4323	dout("check_delayed_caps\n");
4324	spin_lock(&mdsc->cap_delay_lock);
4325	while (!list_empty(&mdsc->cap_delay_list)) {
 
 
4326		ci = list_first_entry(&mdsc->cap_delay_list,
4327				      struct ceph_inode_info,
4328				      i_cap_delay_list);
4329		if (time_before(loop_start, ci->i_hold_caps_max - delay_max)) {
4330			dout("%s caps added recently.  Exiting loop", __func__);
4331			delay = ci->i_hold_caps_max;
4332			break;
4333		}
4334		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
4335		    time_before(jiffies, ci->i_hold_caps_max))
4336			break;
4337		list_del_init(&ci->i_cap_delay_list);
4338
4339		inode = igrab(&ci->netfs.inode);
4340		if (inode) {
4341			spin_unlock(&mdsc->cap_delay_lock);
4342			dout("check_delayed_caps on %p\n", inode);
4343			ceph_check_caps(ci, 0);
4344			iput(inode);
4345			spin_lock(&mdsc->cap_delay_lock);
4346		}
4347	}
4348	spin_unlock(&mdsc->cap_delay_lock);
4349
4350	return delay;
4351}
4352
4353/*
4354 * Flush all dirty caps to the mds
4355 */
4356static void flush_dirty_session_caps(struct ceph_mds_session *s)
4357{
4358	struct ceph_mds_client *mdsc = s->s_mdsc;
4359	struct ceph_inode_info *ci;
4360	struct inode *inode;
4361
4362	dout("flush_dirty_caps\n");
4363	spin_lock(&mdsc->cap_dirty_lock);
4364	while (!list_empty(&s->s_cap_dirty)) {
4365		ci = list_first_entry(&s->s_cap_dirty, struct ceph_inode_info,
4366				      i_dirty_item);
4367		inode = &ci->netfs.inode;
4368		ihold(inode);
4369		dout("flush_dirty_caps %llx.%llx\n", ceph_vinop(inode));
4370		spin_unlock(&mdsc->cap_dirty_lock);
4371		ceph_wait_on_async_create(inode);
4372		ceph_check_caps(ci, CHECK_CAPS_FLUSH);
4373		iput(inode);
4374		spin_lock(&mdsc->cap_dirty_lock);
4375	}
4376	spin_unlock(&mdsc->cap_dirty_lock);
4377	dout("flush_dirty_caps done\n");
4378}
4379
4380void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
4381{
4382	ceph_mdsc_iterate_sessions(mdsc, flush_dirty_session_caps, true);
4383}
4384
4385void __ceph_touch_fmode(struct ceph_inode_info *ci,
4386			struct ceph_mds_client *mdsc, int fmode)
4387{
4388	unsigned long now = jiffies;
4389	if (fmode & CEPH_FILE_MODE_RD)
4390		ci->i_last_rd = now;
4391	if (fmode & CEPH_FILE_MODE_WR)
4392		ci->i_last_wr = now;
4393	/* queue periodic check */
4394	if (fmode &&
4395	    __ceph_is_any_real_caps(ci) &&
4396	    list_empty(&ci->i_cap_delay_list))
4397		__cap_delay_requeue(mdsc, ci);
4398}
4399
4400void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count)
4401{
4402	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(ci->netfs.inode.i_sb);
4403	int bits = (fmode << 1) | 1;
4404	bool already_opened = false;
4405	int i;
4406
4407	if (count == 1)
4408		atomic64_inc(&mdsc->metric.opened_files);
4409
4410	spin_lock(&ci->i_ceph_lock);
4411	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4412		/*
4413		 * If any of the mode ref is larger than 0,
4414		 * that means it has been already opened by
4415		 * others. Just skip checking the PIN ref.
4416		 */
4417		if (i && ci->i_nr_by_mode[i])
4418			already_opened = true;
4419
4420		if (bits & (1 << i))
4421			ci->i_nr_by_mode[i] += count;
4422	}
4423
4424	if (!already_opened)
4425		percpu_counter_inc(&mdsc->metric.opened_inodes);
4426	spin_unlock(&ci->i_ceph_lock);
4427}
4428
4429/*
4430 * Drop open file reference.  If we were the last open file,
4431 * we may need to release capabilities to the MDS (or schedule
4432 * their delayed release).
4433 */
4434void ceph_put_fmode(struct ceph_inode_info *ci, int fmode, int count)
4435{
4436	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(ci->netfs.inode.i_sb);
4437	int bits = (fmode << 1) | 1;
4438	bool is_closed = true;
4439	int i;
4440
4441	if (count == 1)
4442		atomic64_dec(&mdsc->metric.opened_files);
4443
4444	spin_lock(&ci->i_ceph_lock);
4445	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4446		if (bits & (1 << i)) {
4447			BUG_ON(ci->i_nr_by_mode[i] < count);
4448			ci->i_nr_by_mode[i] -= count;
4449		}
4450
4451		/*
4452		 * If any of the mode ref is not 0 after
4453		 * decreased, that means it is still opened
4454		 * by others. Just skip checking the PIN ref.
4455		 */
4456		if (i && ci->i_nr_by_mode[i])
4457			is_closed = false;
4458	}
4459
4460	if (is_closed)
4461		percpu_counter_dec(&mdsc->metric.opened_inodes);
4462	spin_unlock(&ci->i_ceph_lock);
4463}
4464
4465/*
4466 * For a soon-to-be unlinked file, drop the LINK caps. If it
4467 * looks like the link count will hit 0, drop any other caps (other
4468 * than PIN) we don't specifically want (due to the file still being
4469 * open).
4470 */
4471int ceph_drop_caps_for_unlink(struct inode *inode)
4472{
4473	struct ceph_inode_info *ci = ceph_inode(inode);
4474	int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
4475
4476	spin_lock(&ci->i_ceph_lock);
4477	if (inode->i_nlink == 1) {
4478		drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
4479
4480		if (__ceph_caps_dirty(ci)) {
4481			struct ceph_mds_client *mdsc =
4482				ceph_inode_to_client(inode)->mdsc;
4483			__cap_delay_requeue_front(mdsc, ci);
4484		}
4485	}
4486	spin_unlock(&ci->i_ceph_lock);
4487	return drop;
4488}
4489
4490/*
4491 * Helpers for embedding cap and dentry lease releases into mds
4492 * requests.
4493 *
4494 * @force is used by dentry_release (below) to force inclusion of a
4495 * record for the directory inode, even when there aren't any caps to
4496 * drop.
4497 */
4498int ceph_encode_inode_release(void **p, struct inode *inode,
4499			      int mds, int drop, int unless, int force)
4500{
4501	struct ceph_inode_info *ci = ceph_inode(inode);
4502	struct ceph_cap *cap;
4503	struct ceph_mds_request_release *rel = *p;
4504	int used, dirty;
4505	int ret = 0;
4506
4507	spin_lock(&ci->i_ceph_lock);
4508	used = __ceph_caps_used(ci);
4509	dirty = __ceph_caps_dirty(ci);
4510
4511	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
4512	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
4513	     ceph_cap_string(unless));
4514
4515	/* only drop unused, clean caps */
4516	drop &= ~(used | dirty);
4517
4518	cap = __get_cap_for_mds(ci, mds);
4519	if (cap && __cap_is_valid(cap)) {
4520		unless &= cap->issued;
4521		if (unless) {
4522			if (unless & CEPH_CAP_AUTH_EXCL)
4523				drop &= ~CEPH_CAP_AUTH_SHARED;
4524			if (unless & CEPH_CAP_LINK_EXCL)
4525				drop &= ~CEPH_CAP_LINK_SHARED;
4526			if (unless & CEPH_CAP_XATTR_EXCL)
4527				drop &= ~CEPH_CAP_XATTR_SHARED;
4528			if (unless & CEPH_CAP_FILE_EXCL)
4529				drop &= ~CEPH_CAP_FILE_SHARED;
4530		}
4531
4532		if (force || (cap->issued & drop)) {
4533			if (cap->issued & drop) {
4534				int wanted = __ceph_caps_wanted(ci);
 
 
4535				dout("encode_inode_release %p cap %p "
4536				     "%s -> %s, wanted %s -> %s\n", inode, cap,
4537				     ceph_cap_string(cap->issued),
4538				     ceph_cap_string(cap->issued & ~drop),
4539				     ceph_cap_string(cap->mds_wanted),
4540				     ceph_cap_string(wanted));
4541
4542				cap->issued &= ~drop;
4543				cap->implemented &= ~drop;
4544				cap->mds_wanted = wanted;
4545				if (cap == ci->i_auth_cap &&
4546				    !(wanted & CEPH_CAP_ANY_FILE_WR))
4547					ci->i_requested_max_size = 0;
4548			} else {
4549				dout("encode_inode_release %p cap %p %s"
4550				     " (force)\n", inode, cap,
4551				     ceph_cap_string(cap->issued));
4552			}
4553
4554			rel->ino = cpu_to_le64(ceph_ino(inode));
4555			rel->cap_id = cpu_to_le64(cap->cap_id);
4556			rel->seq = cpu_to_le32(cap->seq);
4557			rel->issue_seq = cpu_to_le32(cap->issue_seq);
4558			rel->mseq = cpu_to_le32(cap->mseq);
4559			rel->caps = cpu_to_le32(cap->implemented);
4560			rel->wanted = cpu_to_le32(cap->mds_wanted);
4561			rel->dname_len = 0;
4562			rel->dname_seq = 0;
4563			*p += sizeof(*rel);
4564			ret = 1;
4565		} else {
4566			dout("encode_inode_release %p cap %p %s (noop)\n",
4567			     inode, cap, ceph_cap_string(cap->issued));
4568		}
4569	}
4570	spin_unlock(&ci->i_ceph_lock);
4571	return ret;
4572}
4573
4574int ceph_encode_dentry_release(void **p, struct dentry *dentry,
4575			       struct inode *dir,
4576			       int mds, int drop, int unless)
4577{
4578	struct dentry *parent = NULL;
4579	struct ceph_mds_request_release *rel = *p;
4580	struct ceph_dentry_info *di = ceph_dentry(dentry);
4581	int force = 0;
4582	int ret;
4583
4584	/*
4585	 * force an record for the directory caps if we have a dentry lease.
4586	 * this is racy (can't take i_ceph_lock and d_lock together), but it
4587	 * doesn't have to be perfect; the mds will revoke anything we don't
4588	 * release.
4589	 */
4590	spin_lock(&dentry->d_lock);
4591	if (di->lease_session && di->lease_session->s_mds == mds)
4592		force = 1;
4593	if (!dir) {
4594		parent = dget(dentry->d_parent);
4595		dir = d_inode(parent);
4596	}
4597	spin_unlock(&dentry->d_lock);
4598
4599	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
4600	dput(parent);
4601
4602	spin_lock(&dentry->d_lock);
4603	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
4604		dout("encode_dentry_release %p mds%d seq %d\n",
4605		     dentry, mds, (int)di->lease_seq);
4606		rel->dname_len = cpu_to_le32(dentry->d_name.len);
4607		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
4608		*p += dentry->d_name.len;
4609		rel->dname_seq = cpu_to_le32(di->lease_seq);
4610		__ceph_mdsc_drop_dentry_lease(dentry);
4611	}
4612	spin_unlock(&dentry->d_lock);
4613	return ret;
4614}
4615
4616static int remove_capsnaps(struct ceph_mds_client *mdsc, struct inode *inode)
4617{
4618	struct ceph_inode_info *ci = ceph_inode(inode);
4619	struct ceph_cap_snap *capsnap;
4620	int capsnap_release = 0;
4621
4622	lockdep_assert_held(&ci->i_ceph_lock);
4623
4624	dout("removing capsnaps, ci is %p, inode is %p\n", ci, inode);
4625
4626	while (!list_empty(&ci->i_cap_snaps)) {
4627		capsnap = list_first_entry(&ci->i_cap_snaps,
4628					   struct ceph_cap_snap, ci_item);
4629		__ceph_remove_capsnap(inode, capsnap, NULL, NULL);
4630		ceph_put_snap_context(capsnap->context);
4631		ceph_put_cap_snap(capsnap);
4632		capsnap_release++;
4633	}
4634	wake_up_all(&ci->i_cap_wq);
4635	wake_up_all(&mdsc->cap_flushing_wq);
4636	return capsnap_release;
4637}
4638
4639int ceph_purge_inode_cap(struct inode *inode, struct ceph_cap *cap, bool *invalidate)
4640{
4641	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
4642	struct ceph_mds_client *mdsc = fsc->mdsc;
4643	struct ceph_inode_info *ci = ceph_inode(inode);
4644	bool is_auth;
4645	bool dirty_dropped = false;
4646	int iputs = 0;
4647
4648	lockdep_assert_held(&ci->i_ceph_lock);
4649
4650	dout("removing cap %p, ci is %p, inode is %p\n",
4651	     cap, ci, &ci->netfs.inode);
4652
4653	is_auth = (cap == ci->i_auth_cap);
4654	__ceph_remove_cap(cap, false);
4655	if (is_auth) {
4656		struct ceph_cap_flush *cf;
4657
4658		if (ceph_inode_is_shutdown(inode)) {
4659			if (inode->i_data.nrpages > 0)
4660				*invalidate = true;
4661			if (ci->i_wrbuffer_ref > 0)
4662				mapping_set_error(&inode->i_data, -EIO);
4663		}
4664
4665		spin_lock(&mdsc->cap_dirty_lock);
4666
4667		/* trash all of the cap flushes for this inode */
4668		while (!list_empty(&ci->i_cap_flush_list)) {
4669			cf = list_first_entry(&ci->i_cap_flush_list,
4670					      struct ceph_cap_flush, i_list);
4671			list_del_init(&cf->g_list);
4672			list_del_init(&cf->i_list);
4673			if (!cf->is_capsnap)
4674				ceph_free_cap_flush(cf);
4675		}
4676
4677		if (!list_empty(&ci->i_dirty_item)) {
4678			pr_warn_ratelimited(
4679				" dropping dirty %s state for %p %lld\n",
4680				ceph_cap_string(ci->i_dirty_caps),
4681				inode, ceph_ino(inode));
4682			ci->i_dirty_caps = 0;
4683			list_del_init(&ci->i_dirty_item);
4684			dirty_dropped = true;
4685		}
4686		if (!list_empty(&ci->i_flushing_item)) {
4687			pr_warn_ratelimited(
4688				" dropping dirty+flushing %s state for %p %lld\n",
4689				ceph_cap_string(ci->i_flushing_caps),
4690				inode, ceph_ino(inode));
4691			ci->i_flushing_caps = 0;
4692			list_del_init(&ci->i_flushing_item);
4693			mdsc->num_cap_flushing--;
4694			dirty_dropped = true;
4695		}
4696		spin_unlock(&mdsc->cap_dirty_lock);
4697
4698		if (dirty_dropped) {
4699			mapping_set_error(inode->i_mapping, -EIO);
4700
4701			if (ci->i_wrbuffer_ref_head == 0 &&
4702			    ci->i_wr_ref == 0 &&
4703			    ci->i_dirty_caps == 0 &&
4704			    ci->i_flushing_caps == 0) {
4705				ceph_put_snap_context(ci->i_head_snapc);
4706				ci->i_head_snapc = NULL;
4707			}
4708		}
4709
4710		if (atomic_read(&ci->i_filelock_ref) > 0) {
4711			/* make further file lock syscall return -EIO */
4712			ci->i_ceph_flags |= CEPH_I_ERROR_FILELOCK;
4713			pr_warn_ratelimited(" dropping file locks for %p %lld\n",
4714					    inode, ceph_ino(inode));
4715		}
4716
4717		if (!ci->i_dirty_caps && ci->i_prealloc_cap_flush) {
4718			cf = ci->i_prealloc_cap_flush;
4719			ci->i_prealloc_cap_flush = NULL;
4720			if (!cf->is_capsnap)
4721				ceph_free_cap_flush(cf);
4722		}
4723
4724		if (!list_empty(&ci->i_cap_snaps))
4725			iputs = remove_capsnaps(mdsc, inode);
4726	}
4727	if (dirty_dropped)
4728		++iputs;
4729	return iputs;
4730}