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v3.5.6
 
   1#include <linux/ceph/ceph_debug.h>
   2
   3#include <linux/fs.h>
   4#include <linux/kernel.h>
   5#include <linux/sched.h>
   6#include <linux/slab.h>
   7#include <linux/vmalloc.h>
   8#include <linux/wait.h>
   9#include <linux/writeback.h>
 
  10
  11#include "super.h"
  12#include "mds_client.h"
 
  13#include <linux/ceph/decode.h>
  14#include <linux/ceph/messenger.h>
  15
  16/*
  17 * Capability management
  18 *
  19 * The Ceph metadata servers control client access to inode metadata
  20 * and file data by issuing capabilities, granting clients permission
  21 * to read and/or write both inode field and file data to OSDs
  22 * (storage nodes).  Each capability consists of a set of bits
  23 * indicating which operations are allowed.
  24 *
  25 * If the client holds a *_SHARED cap, the client has a coherent value
  26 * that can be safely read from the cached inode.
  27 *
  28 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
  29 * client is allowed to change inode attributes (e.g., file size,
  30 * mtime), note its dirty state in the ceph_cap, and asynchronously
  31 * flush that metadata change to the MDS.
  32 *
  33 * In the event of a conflicting operation (perhaps by another
  34 * client), the MDS will revoke the conflicting client capabilities.
  35 *
  36 * In order for a client to cache an inode, it must hold a capability
  37 * with at least one MDS server.  When inodes are released, release
  38 * notifications are batched and periodically sent en masse to the MDS
  39 * cluster to release server state.
  40 */
  41
 
 
 
 
 
  42
  43/*
  44 * Generate readable cap strings for debugging output.
  45 */
  46#define MAX_CAP_STR 20
  47static char cap_str[MAX_CAP_STR][40];
  48static DEFINE_SPINLOCK(cap_str_lock);
  49static int last_cap_str;
  50
  51static char *gcap_string(char *s, int c)
  52{
  53	if (c & CEPH_CAP_GSHARED)
  54		*s++ = 's';
  55	if (c & CEPH_CAP_GEXCL)
  56		*s++ = 'x';
  57	if (c & CEPH_CAP_GCACHE)
  58		*s++ = 'c';
  59	if (c & CEPH_CAP_GRD)
  60		*s++ = 'r';
  61	if (c & CEPH_CAP_GWR)
  62		*s++ = 'w';
  63	if (c & CEPH_CAP_GBUFFER)
  64		*s++ = 'b';
 
 
  65	if (c & CEPH_CAP_GLAZYIO)
  66		*s++ = 'l';
  67	return s;
  68}
  69
  70const char *ceph_cap_string(int caps)
  71{
  72	int i;
  73	char *s;
  74	int c;
  75
  76	spin_lock(&cap_str_lock);
  77	i = last_cap_str++;
  78	if (last_cap_str == MAX_CAP_STR)
  79		last_cap_str = 0;
  80	spin_unlock(&cap_str_lock);
  81
  82	s = cap_str[i];
  83
  84	if (caps & CEPH_CAP_PIN)
  85		*s++ = 'p';
  86
  87	c = (caps >> CEPH_CAP_SAUTH) & 3;
  88	if (c) {
  89		*s++ = 'A';
  90		s = gcap_string(s, c);
  91	}
  92
  93	c = (caps >> CEPH_CAP_SLINK) & 3;
  94	if (c) {
  95		*s++ = 'L';
  96		s = gcap_string(s, c);
  97	}
  98
  99	c = (caps >> CEPH_CAP_SXATTR) & 3;
 100	if (c) {
 101		*s++ = 'X';
 102		s = gcap_string(s, c);
 103	}
 104
 105	c = caps >> CEPH_CAP_SFILE;
 106	if (c) {
 107		*s++ = 'F';
 108		s = gcap_string(s, c);
 109	}
 110
 111	if (s == cap_str[i])
 112		*s++ = '-';
 113	*s = 0;
 114	return cap_str[i];
 115}
 116
 117void ceph_caps_init(struct ceph_mds_client *mdsc)
 118{
 119	INIT_LIST_HEAD(&mdsc->caps_list);
 120	spin_lock_init(&mdsc->caps_list_lock);
 121}
 122
 123void ceph_caps_finalize(struct ceph_mds_client *mdsc)
 124{
 125	struct ceph_cap *cap;
 126
 127	spin_lock(&mdsc->caps_list_lock);
 128	while (!list_empty(&mdsc->caps_list)) {
 129		cap = list_first_entry(&mdsc->caps_list,
 130				       struct ceph_cap, caps_item);
 131		list_del(&cap->caps_item);
 132		kmem_cache_free(ceph_cap_cachep, cap);
 133	}
 134	mdsc->caps_total_count = 0;
 135	mdsc->caps_avail_count = 0;
 136	mdsc->caps_use_count = 0;
 137	mdsc->caps_reserve_count = 0;
 138	mdsc->caps_min_count = 0;
 139	spin_unlock(&mdsc->caps_list_lock);
 140}
 141
 142void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
 
 143{
 144	spin_lock(&mdsc->caps_list_lock);
 145	mdsc->caps_min_count += delta;
 146	BUG_ON(mdsc->caps_min_count < 0);
 
 
 
 
 
 147	spin_unlock(&mdsc->caps_list_lock);
 148}
 149
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 150int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 151		      struct ceph_cap_reservation *ctx, int need)
 152{
 153	int i;
 154	struct ceph_cap *cap;
 155	int have;
 156	int alloc = 0;
 
 
 
 
 157	LIST_HEAD(newcaps);
 158	int ret = 0;
 159
 160	dout("reserve caps ctx=%p need=%d\n", ctx, need);
 161
 162	/* first reserve any caps that are already allocated */
 163	spin_lock(&mdsc->caps_list_lock);
 164	if (mdsc->caps_avail_count >= need)
 165		have = need;
 166	else
 167		have = mdsc->caps_avail_count;
 168	mdsc->caps_avail_count -= have;
 169	mdsc->caps_reserve_count += have;
 170	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 171					 mdsc->caps_reserve_count +
 172					 mdsc->caps_avail_count);
 173	spin_unlock(&mdsc->caps_list_lock);
 174
 175	for (i = have; i < need; i++) {
 176		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 177		if (!cap) {
 178			ret = -ENOMEM;
 179			goto out_alloc_count;
 
 
 180		}
 181		list_add(&cap->caps_item, &newcaps);
 182		alloc++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 183	}
 184	BUG_ON(have + alloc != need);
 185
 186	spin_lock(&mdsc->caps_list_lock);
 187	mdsc->caps_total_count += alloc;
 188	mdsc->caps_reserve_count += alloc;
 189	list_splice(&newcaps, &mdsc->caps_list);
 190
 191	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 192					 mdsc->caps_reserve_count +
 193					 mdsc->caps_avail_count);
 
 
 
 
 194	spin_unlock(&mdsc->caps_list_lock);
 195
 196	ctx->count = need;
 197	dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
 198	     ctx, mdsc->caps_total_count, mdsc->caps_use_count,
 199	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 200	return 0;
 201
 202out_alloc_count:
 203	/* we didn't manage to reserve as much as we needed */
 204	pr_warning("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
 205		   ctx, need, have);
 206	return ret;
 207}
 208
 209int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 210			struct ceph_cap_reservation *ctx)
 211{
 
 
 
 
 212	dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
 213	if (ctx->count) {
 214		spin_lock(&mdsc->caps_list_lock);
 215		BUG_ON(mdsc->caps_reserve_count < ctx->count);
 216		mdsc->caps_reserve_count -= ctx->count;
 217		mdsc->caps_avail_count += ctx->count;
 218		ctx->count = 0;
 219		dout("unreserve caps %d = %d used + %d resv + %d avail\n",
 220		     mdsc->caps_total_count, mdsc->caps_use_count,
 221		     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 222		BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 223						 mdsc->caps_reserve_count +
 224						 mdsc->caps_avail_count);
 225		spin_unlock(&mdsc->caps_list_lock);
 226	}
 227	return 0;
 228}
 229
 230static struct ceph_cap *get_cap(struct ceph_mds_client *mdsc,
 231				struct ceph_cap_reservation *ctx)
 232{
 233	struct ceph_cap *cap = NULL;
 234
 235	/* temporary, until we do something about cap import/export */
 236	if (!ctx) {
 237		cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
 238		if (cap) {
 
 239			mdsc->caps_use_count++;
 240			mdsc->caps_total_count++;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 241		}
 
 242		return cap;
 243	}
 244
 245	spin_lock(&mdsc->caps_list_lock);
 246	dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
 247	     ctx, ctx->count, mdsc->caps_total_count, mdsc->caps_use_count,
 248	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 249	BUG_ON(!ctx->count);
 250	BUG_ON(ctx->count > mdsc->caps_reserve_count);
 251	BUG_ON(list_empty(&mdsc->caps_list));
 252
 253	ctx->count--;
 
 254	mdsc->caps_reserve_count--;
 255	mdsc->caps_use_count++;
 256
 257	cap = list_first_entry(&mdsc->caps_list, struct ceph_cap, caps_item);
 258	list_del(&cap->caps_item);
 259
 260	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 261	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 262	spin_unlock(&mdsc->caps_list_lock);
 263	return cap;
 264}
 265
 266void ceph_put_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap)
 267{
 268	spin_lock(&mdsc->caps_list_lock);
 269	dout("put_cap %p %d = %d used + %d resv + %d avail\n",
 270	     cap, mdsc->caps_total_count, mdsc->caps_use_count,
 271	     mdsc->caps_reserve_count, mdsc->caps_avail_count);
 272	mdsc->caps_use_count--;
 273	/*
 274	 * Keep some preallocated caps around (ceph_min_count), to
 275	 * avoid lots of free/alloc churn.
 276	 */
 277	if (mdsc->caps_avail_count >= mdsc->caps_reserve_count +
 278				      mdsc->caps_min_count) {
 279		mdsc->caps_total_count--;
 280		kmem_cache_free(ceph_cap_cachep, cap);
 281	} else {
 282		mdsc->caps_avail_count++;
 283		list_add(&cap->caps_item, &mdsc->caps_list);
 284	}
 285
 286	BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
 287	       mdsc->caps_reserve_count + mdsc->caps_avail_count);
 288	spin_unlock(&mdsc->caps_list_lock);
 289}
 290
 291void ceph_reservation_status(struct ceph_fs_client *fsc,
 292			     int *total, int *avail, int *used, int *reserved,
 293			     int *min)
 294{
 295	struct ceph_mds_client *mdsc = fsc->mdsc;
 296
 
 
 297	if (total)
 298		*total = mdsc->caps_total_count;
 299	if (avail)
 300		*avail = mdsc->caps_avail_count;
 301	if (used)
 302		*used = mdsc->caps_use_count;
 303	if (reserved)
 304		*reserved = mdsc->caps_reserve_count;
 305	if (min)
 306		*min = mdsc->caps_min_count;
 
 
 307}
 308
 309/*
 310 * Find ceph_cap for given mds, if any.
 311 *
 312 * Called with i_ceph_lock held.
 313 */
 314static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 315{
 316	struct ceph_cap *cap;
 317	struct rb_node *n = ci->i_caps.rb_node;
 318
 319	while (n) {
 320		cap = rb_entry(n, struct ceph_cap, ci_node);
 321		if (mds < cap->mds)
 322			n = n->rb_left;
 323		else if (mds > cap->mds)
 324			n = n->rb_right;
 325		else
 326			return cap;
 327	}
 328	return NULL;
 329}
 330
 331struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci, int mds)
 332{
 333	struct ceph_cap *cap;
 334
 335	spin_lock(&ci->i_ceph_lock);
 336	cap = __get_cap_for_mds(ci, mds);
 337	spin_unlock(&ci->i_ceph_lock);
 338	return cap;
 339}
 340
 341/*
 342 * Return id of any MDS with a cap, preferably FILE_WR|BUFFER|EXCL, else -1.
 343 */
 344static int __ceph_get_cap_mds(struct ceph_inode_info *ci)
 345{
 346	struct ceph_cap *cap;
 347	int mds = -1;
 348	struct rb_node *p;
 349
 350	/* prefer mds with WR|BUFFER|EXCL caps */
 351	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 352		cap = rb_entry(p, struct ceph_cap, ci_node);
 353		mds = cap->mds;
 354		if (cap->issued & (CEPH_CAP_FILE_WR |
 355				   CEPH_CAP_FILE_BUFFER |
 356				   CEPH_CAP_FILE_EXCL))
 357			break;
 358	}
 359	return mds;
 360}
 361
 362int ceph_get_cap_mds(struct inode *inode)
 363{
 364	struct ceph_inode_info *ci = ceph_inode(inode);
 365	int mds;
 366	spin_lock(&ci->i_ceph_lock);
 367	mds = __ceph_get_cap_mds(ceph_inode(inode));
 368	spin_unlock(&ci->i_ceph_lock);
 369	return mds;
 370}
 371
 372/*
 373 * Called under i_ceph_lock.
 374 */
 375static void __insert_cap_node(struct ceph_inode_info *ci,
 376			      struct ceph_cap *new)
 377{
 378	struct rb_node **p = &ci->i_caps.rb_node;
 379	struct rb_node *parent = NULL;
 380	struct ceph_cap *cap = NULL;
 381
 382	while (*p) {
 383		parent = *p;
 384		cap = rb_entry(parent, struct ceph_cap, ci_node);
 385		if (new->mds < cap->mds)
 386			p = &(*p)->rb_left;
 387		else if (new->mds > cap->mds)
 388			p = &(*p)->rb_right;
 389		else
 390			BUG();
 391	}
 392
 393	rb_link_node(&new->ci_node, parent, p);
 394	rb_insert_color(&new->ci_node, &ci->i_caps);
 395}
 396
 397/*
 398 * (re)set cap hold timeouts, which control the delayed release
 399 * of unused caps back to the MDS.  Should be called on cap use.
 400 */
 401static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
 402			       struct ceph_inode_info *ci)
 403{
 404	struct ceph_mount_options *ma = mdsc->fsc->mount_options;
 405
 406	ci->i_hold_caps_min = round_jiffies(jiffies +
 407					    ma->caps_wanted_delay_min * HZ);
 408	ci->i_hold_caps_max = round_jiffies(jiffies +
 409					    ma->caps_wanted_delay_max * HZ);
 410	dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
 411	     ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
 412}
 413
 414/*
 415 * (Re)queue cap at the end of the delayed cap release list.
 416 *
 417 * If I_FLUSH is set, leave the inode at the front of the list.
 418 *
 419 * Caller holds i_ceph_lock
 420 *    -> we take mdsc->cap_delay_lock
 421 */
 422static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
 423				struct ceph_inode_info *ci)
 424{
 425	__cap_set_timeouts(mdsc, ci);
 426	dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
 427	     ci->i_ceph_flags, ci->i_hold_caps_max);
 428	if (!mdsc->stopping) {
 429		spin_lock(&mdsc->cap_delay_lock);
 430		if (!list_empty(&ci->i_cap_delay_list)) {
 431			if (ci->i_ceph_flags & CEPH_I_FLUSH)
 432				goto no_change;
 433			list_del_init(&ci->i_cap_delay_list);
 434		}
 
 435		list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 436no_change:
 437		spin_unlock(&mdsc->cap_delay_lock);
 438	}
 439}
 440
 441/*
 442 * Queue an inode for immediate writeback.  Mark inode with I_FLUSH,
 443 * indicating we should send a cap message to flush dirty metadata
 444 * asap, and move to the front of the delayed cap list.
 445 */
 446static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
 447				      struct ceph_inode_info *ci)
 448{
 449	dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
 450	spin_lock(&mdsc->cap_delay_lock);
 451	ci->i_ceph_flags |= CEPH_I_FLUSH;
 452	if (!list_empty(&ci->i_cap_delay_list))
 453		list_del_init(&ci->i_cap_delay_list);
 454	list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
 455	spin_unlock(&mdsc->cap_delay_lock);
 456}
 457
 458/*
 459 * Cancel delayed work on cap.
 460 *
 461 * Caller must hold i_ceph_lock.
 462 */
 463static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
 464			       struct ceph_inode_info *ci)
 465{
 466	dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
 467	if (list_empty(&ci->i_cap_delay_list))
 468		return;
 469	spin_lock(&mdsc->cap_delay_lock);
 470	list_del_init(&ci->i_cap_delay_list);
 471	spin_unlock(&mdsc->cap_delay_lock);
 472}
 473
 474/*
 475 * Common issue checks for add_cap, handle_cap_grant.
 476 */
 477static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
 478			      unsigned issued)
 479{
 480	unsigned had = __ceph_caps_issued(ci, NULL);
 481
 
 
 482	/*
 483	 * Each time we receive FILE_CACHE anew, we increment
 484	 * i_rdcache_gen.
 485	 */
 486	if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
 487	    (had & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
 
 488		ci->i_rdcache_gen++;
 
 489
 490	/*
 491	 * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
 492	 * don't know what happened to this directory while we didn't
 493	 * have the cap.
 
 494	 */
 495	if ((issued & CEPH_CAP_FILE_SHARED) &&
 496	    (had & CEPH_CAP_FILE_SHARED) == 0) {
 497		ci->i_shared_gen++;
 498		if (S_ISDIR(ci->vfs_inode.i_mode))
 499			ceph_dir_clear_complete(&ci->vfs_inode);
 
 
 500	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 501}
 502
 503/*
 504 * Add a capability under the given MDS session.
 505 *
 506 * Caller should hold session snap_rwsem (read) and s_mutex.
 507 *
 508 * @fmode is the open file mode, if we are opening a file, otherwise
 509 * it is < 0.  (This is so we can atomically add the cap and add an
 510 * open file reference to it.)
 511 */
 512int ceph_add_cap(struct inode *inode,
 513		 struct ceph_mds_session *session, u64 cap_id,
 514		 int fmode, unsigned issued, unsigned wanted,
 515		 unsigned seq, unsigned mseq, u64 realmino, int flags,
 516		 struct ceph_cap_reservation *caps_reservation)
 517{
 518	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 519	struct ceph_inode_info *ci = ceph_inode(inode);
 520	struct ceph_cap *new_cap = NULL;
 521	struct ceph_cap *cap;
 522	int mds = session->s_mds;
 523	int actual_wanted;
 
 
 
 524
 525	dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
 526	     session->s_mds, cap_id, ceph_cap_string(issued), seq);
 527
 528	/*
 529	 * If we are opening the file, include file mode wanted bits
 530	 * in wanted.
 531	 */
 532	if (fmode >= 0)
 533		wanted |= ceph_caps_for_mode(fmode);
 534
 535retry:
 536	spin_lock(&ci->i_ceph_lock);
 537	cap = __get_cap_for_mds(ci, mds);
 538	if (!cap) {
 539		if (new_cap) {
 540			cap = new_cap;
 541			new_cap = NULL;
 542		} else {
 543			spin_unlock(&ci->i_ceph_lock);
 544			new_cap = get_cap(mdsc, caps_reservation);
 545			if (new_cap == NULL)
 546				return -ENOMEM;
 547			goto retry;
 548		}
 549
 550		cap->issued = 0;
 551		cap->implemented = 0;
 552		cap->mds = mds;
 553		cap->mds_wanted = 0;
 
 554
 555		cap->ci = ci;
 556		__insert_cap_node(ci, cap);
 557
 558		/* clear out old exporting info?  (i.e. on cap import) */
 559		if (ci->i_cap_exporting_mds == mds) {
 560			ci->i_cap_exporting_issued = 0;
 561			ci->i_cap_exporting_mseq = 0;
 562			ci->i_cap_exporting_mds = -1;
 563		}
 564
 565		/* add to session cap list */
 566		cap->session = session;
 567		spin_lock(&session->s_cap_lock);
 568		list_add_tail(&cap->session_caps, &session->s_caps);
 569		session->s_nr_caps++;
 
 
 
 
 
 570		spin_unlock(&session->s_cap_lock);
 571	} else if (new_cap)
 572		ceph_put_cap(mdsc, new_cap);
 573
 574	if (!ci->i_snap_realm) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 575		/*
 576		 * add this inode to the appropriate snap realm
 577		 */
 578		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 579							       realmino);
 580		if (realm) {
 581			ceph_get_snap_realm(mdsc, realm);
 
 
 
 
 
 
 582			spin_lock(&realm->inodes_with_caps_lock);
 583			ci->i_snap_realm = realm;
 584			list_add(&ci->i_snap_realm_item,
 585				 &realm->inodes_with_caps);
 
 
 
 586			spin_unlock(&realm->inodes_with_caps_lock);
 
 
 
 587		} else {
 588			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 589			       realmino);
 590			WARN_ON(!realm);
 591		}
 592	}
 593
 594	__check_cap_issue(ci, cap, issued);
 595
 596	/*
 597	 * If we are issued caps we don't want, or the mds' wanted
 598	 * value appears to be off, queue a check so we'll release
 599	 * later and/or update the mds wanted value.
 600	 */
 601	actual_wanted = __ceph_caps_wanted(ci);
 602	if ((wanted & ~actual_wanted) ||
 603	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 604		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 605		     ceph_cap_string(issued), ceph_cap_string(wanted),
 606		     ceph_cap_string(actual_wanted));
 607		__cap_delay_requeue(mdsc, ci);
 608	}
 609
 610	if (flags & CEPH_CAP_FLAG_AUTH)
 611		ci->i_auth_cap = cap;
 612	else if (ci->i_auth_cap == cap)
 613		ci->i_auth_cap = NULL;
 
 
 
 
 
 
 
 
 614
 615	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 616	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 617	     ceph_cap_string(issued|cap->issued), seq, mds);
 618	cap->cap_id = cap_id;
 619	cap->issued = issued;
 620	cap->implemented |= issued;
 621	cap->mds_wanted |= wanted;
 
 
 
 622	cap->seq = seq;
 623	cap->issue_seq = seq;
 624	cap->mseq = mseq;
 625	cap->cap_gen = session->s_cap_gen;
 626
 627	if (fmode >= 0)
 628		__ceph_get_fmode(ci, fmode);
 629	spin_unlock(&ci->i_ceph_lock);
 630	wake_up_all(&ci->i_cap_wq);
 631	return 0;
 632}
 633
 634/*
 635 * Return true if cap has not timed out and belongs to the current
 636 * generation of the MDS session (i.e. has not gone 'stale' due to
 637 * us losing touch with the mds).
 638 */
 639static int __cap_is_valid(struct ceph_cap *cap)
 640{
 641	unsigned long ttl;
 642	u32 gen;
 643
 644	spin_lock(&cap->session->s_gen_ttl_lock);
 645	gen = cap->session->s_cap_gen;
 646	ttl = cap->session->s_cap_ttl;
 647	spin_unlock(&cap->session->s_gen_ttl_lock);
 648
 649	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 650		dout("__cap_is_valid %p cap %p issued %s "
 651		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 652		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 653		return 0;
 654	}
 655
 656	return 1;
 657}
 658
 659/*
 660 * Return set of valid cap bits issued to us.  Note that caps time
 661 * out, and may be invalidated in bulk if the client session times out
 662 * and session->s_cap_gen is bumped.
 663 */
 664int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 665{
 666	int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
 667	struct ceph_cap *cap;
 668	struct rb_node *p;
 669
 670	if (implemented)
 671		*implemented = 0;
 672	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 673		cap = rb_entry(p, struct ceph_cap, ci_node);
 674		if (!__cap_is_valid(cap))
 675			continue;
 676		dout("__ceph_caps_issued %p cap %p issued %s\n",
 677		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 678		have |= cap->issued;
 679		if (implemented)
 680			*implemented |= cap->implemented;
 681	}
 
 
 
 
 
 
 
 
 
 682	return have;
 683}
 684
 685/*
 686 * Get cap bits issued by caps other than @ocap
 687 */
 688int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 689{
 690	int have = ci->i_snap_caps;
 691	struct ceph_cap *cap;
 692	struct rb_node *p;
 693
 694	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 695		cap = rb_entry(p, struct ceph_cap, ci_node);
 696		if (cap == ocap)
 697			continue;
 698		if (!__cap_is_valid(cap))
 699			continue;
 700		have |= cap->issued;
 701	}
 702	return have;
 703}
 704
 705/*
 706 * Move a cap to the end of the LRU (oldest caps at list head, newest
 707 * at list tail).
 708 */
 709static void __touch_cap(struct ceph_cap *cap)
 710{
 711	struct ceph_mds_session *s = cap->session;
 712
 713	spin_lock(&s->s_cap_lock);
 714	if (s->s_cap_iterator == NULL) {
 715		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 716		     s->s_mds);
 717		list_move_tail(&cap->session_caps, &s->s_caps);
 718	} else {
 719		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 720		     &cap->ci->vfs_inode, cap, s->s_mds);
 721	}
 722	spin_unlock(&s->s_cap_lock);
 723}
 724
 725/*
 726 * Check if we hold the given mask.  If so, move the cap(s) to the
 727 * front of their respective LRUs.  (This is the preferred way for
 728 * callers to check for caps they want.)
 729 */
 730int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 731{
 732	struct ceph_cap *cap;
 733	struct rb_node *p;
 734	int have = ci->i_snap_caps;
 735
 736	if ((have & mask) == mask) {
 737		dout("__ceph_caps_issued_mask %p snap issued %s"
 738		     " (mask %s)\n", &ci->vfs_inode,
 739		     ceph_cap_string(have),
 740		     ceph_cap_string(mask));
 741		return 1;
 742	}
 743
 744	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 745		cap = rb_entry(p, struct ceph_cap, ci_node);
 746		if (!__cap_is_valid(cap))
 747			continue;
 748		if ((cap->issued & mask) == mask) {
 749			dout("__ceph_caps_issued_mask %p cap %p issued %s"
 750			     " (mask %s)\n", &ci->vfs_inode, cap,
 751			     ceph_cap_string(cap->issued),
 752			     ceph_cap_string(mask));
 753			if (touch)
 754				__touch_cap(cap);
 755			return 1;
 756		}
 757
 758		/* does a combination of caps satisfy mask? */
 759		have |= cap->issued;
 760		if ((have & mask) == mask) {
 761			dout("__ceph_caps_issued_mask %p combo issued %s"
 762			     " (mask %s)\n", &ci->vfs_inode,
 763			     ceph_cap_string(cap->issued),
 764			     ceph_cap_string(mask));
 765			if (touch) {
 766				struct rb_node *q;
 767
 768				/* touch this + preceding caps */
 769				__touch_cap(cap);
 770				for (q = rb_first(&ci->i_caps); q != p;
 771				     q = rb_next(q)) {
 772					cap = rb_entry(q, struct ceph_cap,
 773						       ci_node);
 774					if (!__cap_is_valid(cap))
 775						continue;
 776					__touch_cap(cap);
 
 777				}
 778			}
 779			return 1;
 780		}
 781	}
 782
 783	return 0;
 784}
 785
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 786/*
 787 * Return true if mask caps are currently being revoked by an MDS.
 788 */
 789int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 
 790{
 791	struct inode *inode = &ci->vfs_inode;
 792	struct ceph_cap *cap;
 793	struct rb_node *p;
 794	int ret = 0;
 795
 796	spin_lock(&ci->i_ceph_lock);
 797	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 798		cap = rb_entry(p, struct ceph_cap, ci_node);
 799		if (__cap_is_valid(cap) &&
 800		    (cap->implemented & ~cap->issued & mask)) {
 801			ret = 1;
 802			break;
 803		}
 804	}
 
 
 
 
 
 
 
 
 
 
 805	spin_unlock(&ci->i_ceph_lock);
 806	dout("ceph_caps_revoking %p %s = %d\n", inode,
 807	     ceph_cap_string(mask), ret);
 808	return ret;
 809}
 810
 811int __ceph_caps_used(struct ceph_inode_info *ci)
 812{
 813	int used = 0;
 814	if (ci->i_pin_ref)
 815		used |= CEPH_CAP_PIN;
 816	if (ci->i_rd_ref)
 817		used |= CEPH_CAP_FILE_RD;
 818	if (ci->i_rdcache_ref || ci->vfs_inode.i_data.nrpages)
 
 
 819		used |= CEPH_CAP_FILE_CACHE;
 820	if (ci->i_wr_ref)
 821		used |= CEPH_CAP_FILE_WR;
 822	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 823		used |= CEPH_CAP_FILE_BUFFER;
 
 
 824	return used;
 825}
 826
 
 
 827/*
 828 * wanted, by virtue of open file modes
 829 */
 830int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 831{
 832	int want = 0;
 833	int mode;
 834	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
 835		if (ci->i_nr_by_mode[mode])
 836			want |= ceph_caps_for_mode(mode);
 837	return want;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 838}
 839
 840/*
 841 * Return caps we have registered with the MDS(s) as 'wanted'.
 842 */
 843int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
 844{
 845	struct ceph_cap *cap;
 846	struct rb_node *p;
 847	int mds_wanted = 0;
 848
 849	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 850		cap = rb_entry(p, struct ceph_cap, ci_node);
 851		if (!__cap_is_valid(cap))
 852			continue;
 853		mds_wanted |= cap->mds_wanted;
 
 
 
 854	}
 855	return mds_wanted;
 856}
 857
 858/*
 859 * called under i_ceph_lock
 860 */
 861static int __ceph_is_any_caps(struct ceph_inode_info *ci)
 
 
 
 
 
 
 
 
 
 862{
 863	return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_mds >= 0;
 
 
 
 
 
 
 
 
 
 864}
 865
 866/*
 867 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
 868 *
 869 * caller should hold i_ceph_lock.
 870 * caller will not hold session s_mutex if called from destroy_inode.
 871 */
 872void __ceph_remove_cap(struct ceph_cap *cap)
 873{
 874	struct ceph_mds_session *session = cap->session;
 875	struct ceph_inode_info *ci = cap->ci;
 876	struct ceph_mds_client *mdsc =
 877		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
 878	int removed = 0;
 879
 880	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
 881
 
 
 
 
 
 
 
 882	/* remove from session list */
 883	spin_lock(&session->s_cap_lock);
 884	if (session->s_cap_iterator == cap) {
 885		/* not yet, we are iterating over this very cap */
 886		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
 887		     cap, cap->session);
 888	} else {
 889		list_del_init(&cap->session_caps);
 890		session->s_nr_caps--;
 
 891		cap->session = NULL;
 892		removed = 1;
 893	}
 894	/* protect backpointer with s_cap_lock: see iterate_session_caps */
 895	cap->ci = NULL;
 896	spin_unlock(&session->s_cap_lock);
 897
 898	/* remove from inode list */
 899	rb_erase(&cap->ci_node, &ci->i_caps);
 900	if (ci->i_auth_cap == cap)
 901		ci->i_auth_cap = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 902
 903	if (removed)
 904		ceph_put_cap(mdsc, cap);
 905
 906	if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
 907		struct ceph_snap_realm *realm = ci->i_snap_realm;
 908		spin_lock(&realm->inodes_with_caps_lock);
 909		list_del_init(&ci->i_snap_realm_item);
 910		ci->i_snap_realm_counter++;
 911		ci->i_snap_realm = NULL;
 912		spin_unlock(&realm->inodes_with_caps_lock);
 913		ceph_put_snap_realm(mdsc, realm);
 914	}
 915	if (!__ceph_is_any_real_caps(ci))
 916		__cap_delay_cancel(mdsc, ci);
 
 917}
 918
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 919/*
 920 * Build and send a cap message to the given MDS.
 921 *
 922 * Caller should be holding s_mutex.
 923 */
 924static int send_cap_msg(struct ceph_mds_session *session,
 925			u64 ino, u64 cid, int op,
 926			int caps, int wanted, int dirty,
 927			u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
 928			u64 size, u64 max_size,
 929			struct timespec *mtime, struct timespec *atime,
 930			u64 time_warp_seq,
 931			uid_t uid, gid_t gid, umode_t mode,
 932			u64 xattr_version,
 933			struct ceph_buffer *xattrs_buf,
 934			u64 follows)
 935{
 936	struct ceph_mds_caps *fc;
 937	struct ceph_msg *msg;
 
 
 
 938
 939	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
 940	     " seq %u/%u mseq %u follows %lld size %llu/%llu"
 941	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
 942	     cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
 943	     ceph_cap_string(dirty),
 944	     seq, issue_seq, mseq, follows, size, max_size,
 945	     xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);
 946
 947	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc), GFP_NOFS, false);
 
 
 
 
 
 
 948	if (!msg)
 949		return -ENOMEM;
 950
 951	msg->hdr.tid = cpu_to_le64(flush_tid);
 
 952
 953	fc = msg->front.iov_base;
 954	memset(fc, 0, sizeof(*fc));
 955
 956	fc->cap_id = cpu_to_le64(cid);
 957	fc->op = cpu_to_le32(op);
 958	fc->seq = cpu_to_le32(seq);
 959	fc->issue_seq = cpu_to_le32(issue_seq);
 960	fc->migrate_seq = cpu_to_le32(mseq);
 961	fc->caps = cpu_to_le32(caps);
 962	fc->wanted = cpu_to_le32(wanted);
 963	fc->dirty = cpu_to_le32(dirty);
 964	fc->ino = cpu_to_le64(ino);
 965	fc->snap_follows = cpu_to_le64(follows);
 966
 967	fc->size = cpu_to_le64(size);
 968	fc->max_size = cpu_to_le64(max_size);
 969	if (mtime)
 970		ceph_encode_timespec(&fc->mtime, mtime);
 971	if (atime)
 972		ceph_encode_timespec(&fc->atime, atime);
 973	fc->time_warp_seq = cpu_to_le32(time_warp_seq);
 974
 975	fc->uid = cpu_to_le32(uid);
 976	fc->gid = cpu_to_le32(gid);
 977	fc->mode = cpu_to_le32(mode);
 978
 979	fc->xattr_version = cpu_to_le64(xattr_version);
 980	if (xattrs_buf) {
 981		msg->middle = ceph_buffer_get(xattrs_buf);
 982		fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
 983		msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
 984	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 985
 986	ceph_con_send(&session->s_con, msg);
 987	return 0;
 988}
 
 
 
 
 
 
 989
 990static void __queue_cap_release(struct ceph_mds_session *session,
 991				u64 ino, u64 cap_id, u32 migrate_seq,
 992				u32 issue_seq)
 993{
 994	struct ceph_msg *msg;
 995	struct ceph_mds_cap_release *head;
 996	struct ceph_mds_cap_item *item;
 997
 998	spin_lock(&session->s_cap_lock);
 999	BUG_ON(!session->s_num_cap_releases);
1000	msg = list_first_entry(&session->s_cap_releases,
1001			       struct ceph_msg, list_head);
1002
1003	dout(" adding %llx release to mds%d msg %p (%d left)\n",
1004	     ino, session->s_mds, msg, session->s_num_cap_releases);
1005
1006	BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
1007	head = msg->front.iov_base;
1008	head->num = cpu_to_le32(le32_to_cpu(head->num) + 1);
1009	item = msg->front.iov_base + msg->front.iov_len;
1010	item->ino = cpu_to_le64(ino);
1011	item->cap_id = cpu_to_le64(cap_id);
1012	item->migrate_seq = cpu_to_le32(migrate_seq);
1013	item->seq = cpu_to_le32(issue_seq);
1014
1015	session->s_num_cap_releases--;
1016
1017	msg->front.iov_len += sizeof(*item);
1018	if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
1019		dout(" release msg %p full\n", msg);
1020		list_move_tail(&msg->list_head, &session->s_cap_releases_done);
1021	} else {
1022		dout(" release msg %p at %d/%d (%d)\n", msg,
1023		     (int)le32_to_cpu(head->num),
1024		     (int)CEPH_CAPS_PER_RELEASE,
1025		     (int)msg->front.iov_len);
1026	}
1027	spin_unlock(&session->s_cap_lock);
1028}
1029
1030/*
1031 * Queue cap releases when an inode is dropped from our cache.  Since
1032 * inode is about to be destroyed, there is no need for i_ceph_lock.
1033 */
1034void ceph_queue_caps_release(struct inode *inode)
1035{
1036	struct ceph_inode_info *ci = ceph_inode(inode);
1037	struct rb_node *p;
1038
 
 
 
1039	p = rb_first(&ci->i_caps);
1040	while (p) {
1041		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
1042		struct ceph_mds_session *session = cap->session;
1043
1044		__queue_cap_release(session, ceph_ino(inode), cap->cap_id,
1045				    cap->mseq, cap->issue_seq);
1046		p = rb_next(p);
1047		__ceph_remove_cap(cap);
1048	}
 
1049}
1050
1051/*
1052 * Send a cap msg on the given inode.  Update our caps state, then
1053 * drop i_ceph_lock and send the message.
 
1054 *
1055 * Make note of max_size reported/requested from mds, revoked caps
1056 * that have now been implemented.
1057 *
1058 * Make half-hearted attempt ot to invalidate page cache if we are
1059 * dropping RDCACHE.  Note that this will leave behind locked pages
1060 * that we'll then need to deal with elsewhere.
1061 *
1062 * Return non-zero if delayed release, or we experienced an error
1063 * such that the caller should requeue + retry later.
1064 *
1065 * called with i_ceph_lock, then drops it.
1066 * caller should hold snap_rwsem (read), s_mutex.
1067 */
1068static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1069		      int op, int used, int want, int retain, int flushing,
1070		      unsigned *pflush_tid)
1071	__releases(cap->ci->i_ceph_lock)
1072{
1073	struct ceph_inode_info *ci = cap->ci;
1074	struct inode *inode = &ci->vfs_inode;
1075	u64 cap_id = cap->cap_id;
1076	int held, revoking, dropping, keep;
1077	u64 seq, issue_seq, mseq, time_warp_seq, follows;
1078	u64 size, max_size;
1079	struct timespec mtime, atime;
1080	int wake = 0;
1081	umode_t mode;
1082	uid_t uid;
1083	gid_t gid;
1084	struct ceph_mds_session *session;
1085	u64 xattr_version = 0;
1086	struct ceph_buffer *xattr_blob = NULL;
1087	int delayed = 0;
1088	u64 flush_tid = 0;
1089	int i;
1090	int ret;
1091
1092	held = cap->issued | cap->implemented;
1093	revoking = cap->implemented & ~cap->issued;
1094	retain &= ~revoking;
1095	dropping = cap->issued & ~retain;
1096
1097	dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1098	     inode, cap, cap->session,
1099	     ceph_cap_string(held), ceph_cap_string(held & retain),
1100	     ceph_cap_string(revoking));
1101	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1102
1103	session = cap->session;
1104
1105	/* don't release wanted unless we've waited a bit. */
1106	if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1107	    time_before(jiffies, ci->i_hold_caps_min)) {
1108		dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1109		     ceph_cap_string(cap->issued),
1110		     ceph_cap_string(cap->issued & retain),
1111		     ceph_cap_string(cap->mds_wanted),
1112		     ceph_cap_string(want));
1113		want |= cap->mds_wanted;
1114		retain |= cap->issued;
1115		delayed = 1;
1116	}
1117	ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1118
1119	cap->issued &= retain;  /* drop bits we don't want */
1120	if (cap->implemented & ~cap->issued) {
1121		/*
1122		 * Wake up any waiters on wanted -> needed transition.
1123		 * This is due to the weird transition from buffered
1124		 * to sync IO... we need to flush dirty pages _before_
1125		 * allowing sync writes to avoid reordering.
1126		 */
1127		wake = 1;
1128	}
1129	cap->implemented &= cap->issued | used;
1130	cap->mds_wanted = want;
1131
1132	if (flushing) {
1133		/*
1134		 * assign a tid for flush operations so we can avoid
1135		 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
1136		 * clean type races.  track latest tid for every bit
1137		 * so we can handle flush AxFw, flush Fw, and have the
1138		 * first ack clean Ax.
1139		 */
1140		flush_tid = ++ci->i_cap_flush_last_tid;
1141		if (pflush_tid)
1142			*pflush_tid = flush_tid;
1143		dout(" cap_flush_tid %d\n", (int)flush_tid);
1144		for (i = 0; i < CEPH_CAP_BITS; i++)
1145			if (flushing & (1 << i))
1146				ci->i_cap_flush_tid[i] = flush_tid;
 
1147
1148		follows = ci->i_head_snapc->seq;
 
 
 
1149	} else {
1150		follows = 0;
 
1151	}
1152
1153	keep = cap->implemented;
1154	seq = cap->seq;
1155	issue_seq = cap->issue_seq;
1156	mseq = cap->mseq;
1157	size = inode->i_size;
1158	ci->i_reported_size = size;
1159	max_size = ci->i_wanted_max_size;
1160	ci->i_requested_max_size = max_size;
1161	mtime = inode->i_mtime;
1162	atime = inode->i_atime;
1163	time_warp_seq = ci->i_time_warp_seq;
1164	uid = inode->i_uid;
1165	gid = inode->i_gid;
1166	mode = inode->i_mode;
1167
1168	if (flushing & CEPH_CAP_XATTR_EXCL) {
1169		__ceph_build_xattrs_blob(ci);
1170		xattr_blob = ci->i_xattrs.blob;
1171		xattr_version = ci->i_xattrs.version;
 
 
 
 
 
 
 
 
 
 
 
 
 
1172	}
 
 
1173
1174	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
1175
1176	ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
1177		op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
1178		size, max_size, &mtime, &atime, time_warp_seq,
1179		uid, gid, mode, xattr_version, xattr_blob,
1180		follows);
1181	if (ret < 0) {
1182		dout("error sending cap msg, must requeue %p\n", inode);
1183		delayed = 1;
 
 
 
 
 
1184	}
1185
1186	if (wake)
 
 
1187		wake_up_all(&ci->i_cap_wq);
 
1188
1189	return delayed;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1190}
1191
1192/*
1193 * When a snapshot is taken, clients accumulate dirty metadata on
1194 * inodes with capabilities in ceph_cap_snaps to describe the file
1195 * state at the time the snapshot was taken.  This must be flushed
1196 * asynchronously back to the MDS once sync writes complete and dirty
1197 * data is written out.
1198 *
1199 * Unless @again is true, skip cap_snaps that were already sent to
1200 * the MDS (i.e., during this session).
1201 *
1202 * Called under i_ceph_lock.  Takes s_mutex as needed.
1203 */
1204void __ceph_flush_snaps(struct ceph_inode_info *ci,
1205			struct ceph_mds_session **psession,
1206			int again)
1207		__releases(ci->i_ceph_lock)
1208		__acquires(ci->i_ceph_lock)
1209{
1210	struct inode *inode = &ci->vfs_inode;
1211	int mds;
1212	struct ceph_cap_snap *capsnap;
1213	u32 mseq;
1214	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1215	struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
1216						    session->s_mutex */
1217	u64 next_follows = 0;  /* keep track of how far we've gotten through the
1218			     i_cap_snaps list, and skip these entries next time
1219			     around to avoid an infinite loop */
1220
1221	if (psession)
1222		session = *psession;
1223
1224	dout("__flush_snaps %p\n", inode);
1225retry:
1226	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1227		/* avoid an infiniute loop after retry */
1228		if (capsnap->follows < next_follows)
1229			continue;
1230		/*
1231		 * we need to wait for sync writes to complete and for dirty
1232		 * pages to be written out.
1233		 */
1234		if (capsnap->dirty_pages || capsnap->writing)
1235			break;
1236
1237		/*
1238		 * if cap writeback already occurred, we should have dropped
1239		 * the capsnap in ceph_put_wrbuffer_cap_refs.
1240		 */
1241		BUG_ON(capsnap->dirty == 0);
1242
1243		/* pick mds, take s_mutex */
1244		if (ci->i_auth_cap == NULL) {
1245			dout("no auth cap (migrating?), doing nothing\n");
1246			goto out;
1247		}
1248
1249		/* only flush each capsnap once */
1250		if (!again && !list_empty(&capsnap->flushing_item)) {
1251			dout("already flushed %p, skipping\n", capsnap);
1252			continue;
1253		}
1254
1255		mds = ci->i_auth_cap->session->s_mds;
1256		mseq = ci->i_auth_cap->mseq;
 
 
 
 
 
 
 
 
 
1257
1258		if (session && session->s_mds != mds) {
1259			dout("oops, wrong session %p mutex\n", session);
1260			mutex_unlock(&session->s_mutex);
1261			ceph_put_mds_session(session);
1262			session = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1263		}
1264		if (!session) {
1265			spin_unlock(&ci->i_ceph_lock);
1266			mutex_lock(&mdsc->mutex);
1267			session = __ceph_lookup_mds_session(mdsc, mds);
1268			mutex_unlock(&mdsc->mutex);
1269			if (session) {
1270				dout("inverting session/ino locks on %p\n",
1271				     session);
1272				mutex_lock(&session->s_mutex);
1273			}
1274			/*
1275			 * if session == NULL, we raced against a cap
1276			 * deletion or migration.  retry, and we'll
1277			 * get a better @mds value next time.
1278			 */
1279			spin_lock(&ci->i_ceph_lock);
1280			goto retry;
1281		}
 
 
1282
1283		capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
1284		atomic_inc(&capsnap->nref);
1285		if (!list_empty(&capsnap->flushing_item))
1286			list_del_init(&capsnap->flushing_item);
1287		list_add_tail(&capsnap->flushing_item,
1288			      &session->s_cap_snaps_flushing);
1289		spin_unlock(&ci->i_ceph_lock);
1290
1291		dout("flush_snaps %p cap_snap %p follows %lld tid %llu\n",
1292		     inode, capsnap, capsnap->follows, capsnap->flush_tid);
1293		send_cap_msg(session, ceph_vino(inode).ino, 0,
1294			     CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
1295			     capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
1296			     capsnap->size, 0,
1297			     &capsnap->mtime, &capsnap->atime,
1298			     capsnap->time_warp_seq,
1299			     capsnap->uid, capsnap->gid, capsnap->mode,
1300			     capsnap->xattr_version, capsnap->xattr_blob,
1301			     capsnap->follows);
1302
1303		next_follows = capsnap->follows + 1;
1304		ceph_put_cap_snap(capsnap);
 
 
 
 
 
1305
 
1306		spin_lock(&ci->i_ceph_lock);
1307		goto retry;
1308	}
 
1309
1310	/* we flushed them all; remove this inode from the queue */
1311	spin_lock(&mdsc->snap_flush_lock);
1312	list_del_init(&ci->i_snap_flush_item);
1313	spin_unlock(&mdsc->snap_flush_lock);
 
 
 
1314
1315out:
1316	if (psession)
1317		*psession = session;
1318	else if (session) {
 
 
 
 
 
 
 
 
 
 
 
 
 
1319		mutex_unlock(&session->s_mutex);
1320		ceph_put_mds_session(session);
 
 
 
 
 
 
 
 
 
 
 
 
1321	}
1322}
1323
1324static void ceph_flush_snaps(struct ceph_inode_info *ci)
1325{
1326	spin_lock(&ci->i_ceph_lock);
1327	__ceph_flush_snaps(ci, NULL, 0);
 
 
1328	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
1329}
1330
1331/*
1332 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1333 * Caller is then responsible for calling __mark_inode_dirty with the
1334 * returned flags value.
1335 */
1336int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
 
1337{
1338	struct ceph_mds_client *mdsc =
1339		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1340	struct inode *inode = &ci->vfs_inode;
1341	int was = ci->i_dirty_caps;
1342	int dirty = 0;
1343
 
 
 
 
 
 
 
 
 
1344	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1345	     ceph_cap_string(mask), ceph_cap_string(was),
1346	     ceph_cap_string(was | mask));
1347	ci->i_dirty_caps |= mask;
1348	if (was == 0) {
1349		if (!ci->i_head_snapc)
 
 
 
 
 
 
1350			ci->i_head_snapc = ceph_get_snap_context(
1351				ci->i_snap_realm->cached_context);
1352		dout(" inode %p now dirty snapc %p\n", &ci->vfs_inode,
1353			ci->i_head_snapc);
 
1354		BUG_ON(!list_empty(&ci->i_dirty_item));
1355		spin_lock(&mdsc->cap_dirty_lock);
1356		list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1357		spin_unlock(&mdsc->cap_dirty_lock);
1358		if (ci->i_flushing_caps == 0) {
1359			ihold(inode);
1360			dirty |= I_DIRTY_SYNC;
1361		}
 
 
1362	}
1363	BUG_ON(list_empty(&ci->i_dirty_item));
1364	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1365	    (mask & CEPH_CAP_FILE_BUFFER))
1366		dirty |= I_DIRTY_DATASYNC;
1367	__cap_delay_requeue(mdsc, ci);
1368	return dirty;
1369}
1370
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1371/*
1372 * Add dirty inode to the flushing list.  Assigned a seq number so we
1373 * can wait for caps to flush without starving.
1374 *
1375 * Called under i_ceph_lock.
1376 */
1377static int __mark_caps_flushing(struct inode *inode,
1378				 struct ceph_mds_session *session)
 
1379{
1380	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1381	struct ceph_inode_info *ci = ceph_inode(inode);
 
1382	int flushing;
1383
 
1384	BUG_ON(ci->i_dirty_caps == 0);
1385	BUG_ON(list_empty(&ci->i_dirty_item));
 
1386
1387	flushing = ci->i_dirty_caps;
1388	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1389	     ceph_cap_string(flushing),
1390	     ceph_cap_string(ci->i_flushing_caps),
1391	     ceph_cap_string(ci->i_flushing_caps | flushing));
1392	ci->i_flushing_caps |= flushing;
1393	ci->i_dirty_caps = 0;
1394	dout(" inode %p now !dirty\n", inode);
1395
 
 
 
 
1396	spin_lock(&mdsc->cap_dirty_lock);
1397	list_del_init(&ci->i_dirty_item);
1398
1399	ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
 
 
 
1400	if (list_empty(&ci->i_flushing_item)) {
1401		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1402		mdsc->num_cap_flushing++;
1403		dout(" inode %p now flushing seq %lld\n", inode,
1404		     ci->i_cap_flush_seq);
1405	} else {
1406		list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1407		dout(" inode %p now flushing (more) seq %lld\n", inode,
1408		     ci->i_cap_flush_seq);
1409	}
1410	spin_unlock(&mdsc->cap_dirty_lock);
1411
1412	return flushing;
 
 
1413}
1414
1415/*
1416 * try to invalidate mapping pages without blocking.
1417 */
1418static int try_nonblocking_invalidate(struct inode *inode)
1419{
1420	struct ceph_inode_info *ci = ceph_inode(inode);
1421	u32 invalidating_gen = ci->i_rdcache_gen;
1422
1423	spin_unlock(&ci->i_ceph_lock);
1424	invalidate_mapping_pages(&inode->i_data, 0, -1);
1425	spin_lock(&ci->i_ceph_lock);
1426
1427	if (inode->i_data.nrpages == 0 &&
1428	    invalidating_gen == ci->i_rdcache_gen) {
1429		/* success. */
1430		dout("try_nonblocking_invalidate %p success\n", inode);
1431		/* save any racing async invalidate some trouble */
1432		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1433		return 0;
1434	}
1435	dout("try_nonblocking_invalidate %p failed\n", inode);
1436	return -1;
1437}
1438
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1439/*
1440 * Swiss army knife function to examine currently used and wanted
1441 * versus held caps.  Release, flush, ack revoked caps to mds as
1442 * appropriate.
1443 *
1444 *  CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1445 *    cap release further.
1446 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1447 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1448 *    further delay.
1449 */
1450void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1451		     struct ceph_mds_session *session)
1452{
1453	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1454	struct ceph_mds_client *mdsc = fsc->mdsc;
1455	struct inode *inode = &ci->vfs_inode;
1456	struct ceph_cap *cap;
1457	int file_wanted, used;
 
1458	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1459	int issued, implemented, want, retain, revoking, flushing = 0;
1460	int mds = -1;   /* keep track of how far we've gone through i_caps list
1461			   to avoid an infinite loop on retry */
1462	struct rb_node *p;
1463	int tried_invalidate = 0;
1464	int delayed = 0, sent = 0, force_requeue = 0, num;
1465	int queue_invalidate = 0;
1466	int is_delayed = flags & CHECK_CAPS_NODELAY;
1467
1468	/* if we are unmounting, flush any unused caps immediately. */
1469	if (mdsc->stopping)
1470		is_delayed = 1;
1471
1472	spin_lock(&ci->i_ceph_lock);
1473
1474	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1475		flags |= CHECK_CAPS_FLUSH;
1476
1477	/* flush snaps first time around only */
1478	if (!list_empty(&ci->i_cap_snaps))
1479		__ceph_flush_snaps(ci, &session, 0);
1480	goto retry_locked;
1481retry:
1482	spin_lock(&ci->i_ceph_lock);
1483retry_locked:
1484	file_wanted = __ceph_caps_file_wanted(ci);
1485	used = __ceph_caps_used(ci);
1486	want = file_wanted | used;
1487	issued = __ceph_caps_issued(ci, &implemented);
1488	revoking = implemented & ~issued;
1489
1490	retain = want | CEPH_CAP_PIN;
 
1491	if (!mdsc->stopping && inode->i_nlink > 0) {
1492		if (want) {
1493			retain |= CEPH_CAP_ANY;       /* be greedy */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1494		} else {
 
1495			retain |= CEPH_CAP_ANY_SHARED;
1496			/*
1497			 * keep RD only if we didn't have the file open RW,
1498			 * because then the mds would revoke it anyway to
1499			 * journal max_size=0.
1500			 */
1501			if (ci->i_max_size == 0)
1502				retain |= CEPH_CAP_ANY_RD;
1503		}
1504	}
1505
1506	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1507	     " issued %s revoking %s retain %s %s%s%s\n", inode,
1508	     ceph_cap_string(file_wanted),
1509	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1510	     ceph_cap_string(ci->i_flushing_caps),
1511	     ceph_cap_string(issued), ceph_cap_string(revoking),
1512	     ceph_cap_string(retain),
1513	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1514	     (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1515	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1516
1517	/*
1518	 * If we no longer need to hold onto old our caps, and we may
1519	 * have cached pages, but don't want them, then try to invalidate.
1520	 * If we fail, it's because pages are locked.... try again later.
1521	 */
1522	if ((!is_delayed || mdsc->stopping) &&
1523	    ci->i_wrbuffer_ref == 0 &&               /* no dirty pages... */
1524	    inode->i_data.nrpages &&                 /* have cached pages */
1525	    (file_wanted == 0 ||                     /* no open files */
1526	     (revoking & (CEPH_CAP_FILE_CACHE|
1527			  CEPH_CAP_FILE_LAZYIO))) && /*  or revoking cache */
1528	    !tried_invalidate) {
1529		dout("check_caps trying to invalidate on %p\n", inode);
1530		if (try_nonblocking_invalidate(inode) < 0) {
1531			if (revoking & (CEPH_CAP_FILE_CACHE|
1532					CEPH_CAP_FILE_LAZYIO)) {
1533				dout("check_caps queuing invalidate\n");
1534				queue_invalidate = 1;
1535				ci->i_rdcache_revoking = ci->i_rdcache_gen;
1536			} else {
1537				dout("check_caps failed to invalidate pages\n");
1538				/* we failed to invalidate pages.  check these
1539				   caps again later. */
1540				force_requeue = 1;
1541				__cap_set_timeouts(mdsc, ci);
1542			}
1543		}
1544		tried_invalidate = 1;
1545		goto retry_locked;
1546	}
1547
1548	num = 0;
1549	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 
 
 
1550		cap = rb_entry(p, struct ceph_cap, ci_node);
1551		num++;
1552
1553		/* avoid looping forever */
1554		if (mds >= cap->mds ||
1555		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1556			continue;
1557
1558		/* NOTE: no side-effects allowed, until we take s_mutex */
1559
 
 
 
 
1560		revoking = cap->implemented & ~cap->issued;
1561		dout(" mds%d cap %p issued %s implemented %s revoking %s\n",
1562		     cap->mds, cap, ceph_cap_string(cap->issued),
 
1563		     ceph_cap_string(cap->implemented),
1564		     ceph_cap_string(revoking));
1565
1566		if (cap == ci->i_auth_cap &&
1567		    (cap->issued & CEPH_CAP_FILE_WR)) {
1568			/* request larger max_size from MDS? */
1569			if (ci->i_wanted_max_size > ci->i_max_size &&
1570			    ci->i_wanted_max_size > ci->i_requested_max_size) {
1571				dout("requesting new max_size\n");
1572				goto ack;
1573			}
1574
1575			/* approaching file_max? */
1576			if ((inode->i_size << 1) >= ci->i_max_size &&
1577			    (ci->i_reported_size << 1) < ci->i_max_size) {
1578				dout("i_size approaching max_size\n");
1579				goto ack;
1580			}
1581		}
1582		/* flush anything dirty? */
1583		if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
1584		    ci->i_dirty_caps) {
1585			dout("flushing dirty caps\n");
1586			goto ack;
 
 
 
 
 
1587		}
1588
1589		/* completed revocation? going down and there are no caps? */
1590		if (revoking && (revoking & used) == 0) {
1591			dout("completed revocation of %s\n",
1592			     ceph_cap_string(cap->implemented & ~cap->issued));
1593			goto ack;
1594		}
1595
1596		/* want more caps from mds? */
1597		if (want & ~(cap->mds_wanted | cap->issued))
1598			goto ack;
 
 
 
 
1599
1600		/* things we might delay */
1601		if ((cap->issued & ~retain) == 0 &&
1602		    cap->mds_wanted == want)
1603			continue;     /* nope, all good */
1604
1605		if (is_delayed)
1606			goto ack;
1607
1608		/* delay? */
1609		if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1610		    time_before(jiffies, ci->i_hold_caps_max)) {
1611			dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1612			     ceph_cap_string(cap->issued),
1613			     ceph_cap_string(cap->issued & retain),
1614			     ceph_cap_string(cap->mds_wanted),
1615			     ceph_cap_string(want));
1616			delayed++;
1617			continue;
1618		}
1619
1620ack:
1621		if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1622			dout(" skipping %p I_NOFLUSH set\n", inode);
1623			continue;
1624		}
1625
1626		if (session && session != cap->session) {
1627			dout("oops, wrong session %p mutex\n", session);
1628			mutex_unlock(&session->s_mutex);
1629			session = NULL;
1630		}
1631		if (!session) {
1632			session = cap->session;
1633			if (mutex_trylock(&session->s_mutex) == 0) {
1634				dout("inverting session/ino locks on %p\n",
1635				     session);
 
1636				spin_unlock(&ci->i_ceph_lock);
1637				if (took_snap_rwsem) {
1638					up_read(&mdsc->snap_rwsem);
1639					took_snap_rwsem = 0;
1640				}
1641				mutex_lock(&session->s_mutex);
 
 
 
 
 
 
 
 
 
 
 
1642				goto retry;
1643			}
1644		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1645		/* take snap_rwsem after session mutex */
1646		if (!took_snap_rwsem) {
1647			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1648				dout("inverting snap/in locks on %p\n",
1649				     inode);
1650				spin_unlock(&ci->i_ceph_lock);
1651				down_read(&mdsc->snap_rwsem);
1652				took_snap_rwsem = 1;
1653				goto retry;
1654			}
1655			took_snap_rwsem = 1;
1656		}
1657
1658		if (cap == ci->i_auth_cap && ci->i_dirty_caps)
1659			flushing = __mark_caps_flushing(inode, session);
1660		else
 
 
 
 
 
1661			flushing = 0;
 
 
 
 
 
1662
1663		mds = cap->mds;  /* remember mds, so we don't repeat */
1664		sent++;
1665
1666		/* __send_cap drops i_ceph_lock */
1667		delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, used, want,
1668				      retain, flushing, NULL);
 
 
 
1669		goto retry; /* retake i_ceph_lock and restart our cap scan. */
1670	}
1671
1672	/*
1673	 * Reschedule delayed caps release if we delayed anything,
1674	 * otherwise cancel.
1675	 */
1676	if (delayed && is_delayed)
1677		force_requeue = 1;   /* __send_cap delayed release; requeue */
1678	if (!delayed && !is_delayed)
1679		__cap_delay_cancel(mdsc, ci);
1680	else if (!is_delayed || force_requeue)
1681		__cap_delay_requeue(mdsc, ci);
 
1682
1683	spin_unlock(&ci->i_ceph_lock);
1684
1685	if (queue_invalidate)
1686		ceph_queue_invalidate(inode);
1687
1688	if (session)
1689		mutex_unlock(&session->s_mutex);
1690	if (took_snap_rwsem)
1691		up_read(&mdsc->snap_rwsem);
1692}
1693
1694/*
1695 * Try to flush dirty caps back to the auth mds.
1696 */
1697static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
1698			  unsigned *flush_tid)
1699{
1700	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1701	struct ceph_inode_info *ci = ceph_inode(inode);
1702	int unlock_session = session ? 0 : 1;
1703	int flushing = 0;
 
1704
1705retry:
1706	spin_lock(&ci->i_ceph_lock);
1707	if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1708		dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1709		goto out;
1710	}
1711	if (ci->i_dirty_caps && ci->i_auth_cap) {
1712		struct ceph_cap *cap = ci->i_auth_cap;
1713		int used = __ceph_caps_used(ci);
1714		int want = __ceph_caps_wanted(ci);
1715		int delayed;
1716
1717		if (!session) {
1718			spin_unlock(&ci->i_ceph_lock);
 
 
1719			session = cap->session;
1720			mutex_lock(&session->s_mutex);
1721			goto retry;
1722		}
1723		BUG_ON(session != cap->session);
1724		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
1725			goto out;
 
1726
1727		flushing = __mark_caps_flushing(inode, session);
1728
1729		/* __send_cap drops i_ceph_lock */
1730		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
1731				     cap->issued | cap->implemented, flushing,
1732				     flush_tid);
1733		if (!delayed)
1734			goto out_unlocked;
 
 
 
 
 
 
 
 
 
 
1735
1736		spin_lock(&ci->i_ceph_lock);
1737		__cap_delay_requeue(mdsc, ci);
 
 
 
 
 
 
 
 
 
1738	}
1739out:
1740	spin_unlock(&ci->i_ceph_lock);
1741out_unlocked:
1742	if (session && unlock_session)
1743		mutex_unlock(&session->s_mutex);
 
 
1744	return flushing;
1745}
1746
1747/*
1748 * Return true if we've flushed caps through the given flush_tid.
1749 */
1750static int caps_are_flushed(struct inode *inode, unsigned tid)
1751{
1752	struct ceph_inode_info *ci = ceph_inode(inode);
1753	int i, ret = 1;
1754
1755	spin_lock(&ci->i_ceph_lock);
1756	for (i = 0; i < CEPH_CAP_BITS; i++)
1757		if ((ci->i_flushing_caps & (1 << i)) &&
1758		    ci->i_cap_flush_tid[i] <= tid) {
1759			/* still flushing this bit */
 
1760			ret = 0;
1761			break;
1762		}
1763	spin_unlock(&ci->i_ceph_lock);
1764	return ret;
1765}
1766
1767/*
1768 * Wait on any unsafe replies for the given inode.  First wait on the
1769 * newest request, and make that the upper bound.  Then, if there are
1770 * more requests, keep waiting on the oldest as long as it is still older
1771 * than the original request.
1772 */
1773static void sync_write_wait(struct inode *inode)
1774{
1775	struct ceph_inode_info *ci = ceph_inode(inode);
1776	struct list_head *head = &ci->i_unsafe_writes;
1777	struct ceph_osd_request *req;
1778	u64 last_tid;
1779
1780	spin_lock(&ci->i_unsafe_lock);
1781	if (list_empty(head))
1782		goto out;
1783
1784	/* set upper bound as _last_ entry in chain */
1785	req = list_entry(head->prev, struct ceph_osd_request,
1786			 r_unsafe_item);
1787	last_tid = req->r_tid;
1788
1789	do {
1790		ceph_osdc_get_request(req);
1791		spin_unlock(&ci->i_unsafe_lock);
1792		dout("sync_write_wait on tid %llu (until %llu)\n",
1793		     req->r_tid, last_tid);
1794		wait_for_completion(&req->r_safe_completion);
1795		spin_lock(&ci->i_unsafe_lock);
1796		ceph_osdc_put_request(req);
1797
1798		/*
1799		 * from here on look at first entry in chain, since we
1800		 * only want to wait for anything older than last_tid
1801		 */
1802		if (list_empty(head))
1803			break;
1804		req = list_entry(head->next, struct ceph_osd_request,
1805				 r_unsafe_item);
1806	} while (req->r_tid < last_tid);
1807out:
1808	spin_unlock(&ci->i_unsafe_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1809}
1810
1811int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
1812{
 
1813	struct inode *inode = file->f_mapping->host;
1814	struct ceph_inode_info *ci = ceph_inode(inode);
1815	unsigned flush_tid;
1816	int ret;
1817	int dirty;
1818
1819	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
1820	sync_write_wait(inode);
1821
1822	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1823	if (ret < 0)
1824		return ret;
1825	mutex_lock(&inode->i_mutex);
 
 
 
1826
1827	dirty = try_flush_caps(inode, NULL, &flush_tid);
1828	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
1829
 
 
1830	/*
1831	 * only wait on non-file metadata writeback (the mds
1832	 * can recover size and mtime, so we don't need to
1833	 * wait for that)
1834	 */
1835	if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
1836		dout("fsync waiting for flush_tid %u\n", flush_tid);
1837		ret = wait_event_interruptible(ci->i_cap_wq,
1838				       caps_are_flushed(inode, flush_tid));
1839	}
1840
1841	dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
1842	mutex_unlock(&inode->i_mutex);
 
 
 
 
 
 
 
 
 
 
 
1843	return ret;
1844}
1845
1846/*
1847 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
1848 * queue inode for flush but don't do so immediately, because we can
1849 * get by with fewer MDS messages if we wait for data writeback to
1850 * complete first.
1851 */
1852int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
1853{
1854	struct ceph_inode_info *ci = ceph_inode(inode);
1855	unsigned flush_tid;
1856	int err = 0;
1857	int dirty;
1858	int wait = wbc->sync_mode == WB_SYNC_ALL;
1859
1860	dout("write_inode %p wait=%d\n", inode, wait);
1861	if (wait) {
1862		dirty = try_flush_caps(inode, NULL, &flush_tid);
1863		if (dirty)
1864			err = wait_event_interruptible(ci->i_cap_wq,
1865				       caps_are_flushed(inode, flush_tid));
1866	} else {
1867		struct ceph_mds_client *mdsc =
1868			ceph_sb_to_client(inode->i_sb)->mdsc;
1869
1870		spin_lock(&ci->i_ceph_lock);
1871		if (__ceph_caps_dirty(ci))
1872			__cap_delay_requeue_front(mdsc, ci);
1873		spin_unlock(&ci->i_ceph_lock);
1874	}
1875	return err;
1876}
1877
1878/*
1879 * After a recovering MDS goes active, we need to resend any caps
1880 * we were flushing.
1881 *
1882 * Caller holds session->s_mutex.
1883 */
1884static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1885				   struct ceph_mds_session *session)
1886{
1887	struct ceph_cap_snap *capsnap;
 
 
1888
1889	dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
1890	list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
1891			    flushing_item) {
1892		struct ceph_inode_info *ci = capsnap->ci;
1893		struct inode *inode = &ci->vfs_inode;
1894		struct ceph_cap *cap;
1895
 
 
 
 
 
1896		spin_lock(&ci->i_ceph_lock);
1897		cap = ci->i_auth_cap;
1898		if (cap && cap->session == session) {
1899			dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
1900			     cap, capsnap);
1901			__ceph_flush_snaps(ci, &session, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1902		} else {
1903			pr_err("%p auth cap %p not mds%d ???\n", inode,
1904			       cap, session->s_mds);
1905		}
 
1906		spin_unlock(&ci->i_ceph_lock);
1907	}
1908}
1909
1910void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
1911			     struct ceph_mds_session *session)
1912{
1913	struct ceph_inode_info *ci;
 
 
1914
1915	kick_flushing_capsnaps(mdsc, session);
1916
1917	dout("kick_flushing_caps mds%d\n", session->s_mds);
1918	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
1919		struct inode *inode = &ci->vfs_inode;
1920		struct ceph_cap *cap;
1921		int delayed = 0;
1922
 
 
 
 
 
1923		spin_lock(&ci->i_ceph_lock);
1924		cap = ci->i_auth_cap;
1925		if (cap && cap->session == session) {
1926			dout("kick_flushing_caps %p cap %p %s\n", inode,
1927			     cap, ceph_cap_string(ci->i_flushing_caps));
1928			delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1929					     __ceph_caps_used(ci),
1930					     __ceph_caps_wanted(ci),
1931					     cap->issued | cap->implemented,
1932					     ci->i_flushing_caps, NULL);
1933			if (delayed) {
1934				spin_lock(&ci->i_ceph_lock);
1935				__cap_delay_requeue(mdsc, ci);
1936				spin_unlock(&ci->i_ceph_lock);
1937			}
1938		} else {
1939			pr_err("%p auth cap %p not mds%d ???\n", inode,
1940			       cap, session->s_mds);
1941			spin_unlock(&ci->i_ceph_lock);
 
1942		}
 
 
 
 
 
1943	}
1944}
1945
1946static void kick_flushing_inode_caps(struct ceph_mds_client *mdsc,
1947				     struct ceph_mds_session *session,
1948				     struct inode *inode)
1949{
1950	struct ceph_inode_info *ci = ceph_inode(inode);
1951	struct ceph_cap *cap;
1952	int delayed = 0;
1953
1954	spin_lock(&ci->i_ceph_lock);
1955	cap = ci->i_auth_cap;
1956	dout("kick_flushing_inode_caps %p flushing %s flush_seq %lld\n", inode,
1957	     ceph_cap_string(ci->i_flushing_caps), ci->i_cap_flush_seq);
1958	__ceph_flush_snaps(ci, &session, 1);
1959	if (ci->i_flushing_caps) {
1960		delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1961				     __ceph_caps_used(ci),
1962				     __ceph_caps_wanted(ci),
1963				     cap->issued | cap->implemented,
1964				     ci->i_flushing_caps, NULL);
1965		if (delayed) {
1966			spin_lock(&ci->i_ceph_lock);
1967			__cap_delay_requeue(mdsc, ci);
1968			spin_unlock(&ci->i_ceph_lock);
1969		}
1970	} else {
1971		spin_unlock(&ci->i_ceph_lock);
1972	}
1973}
1974
1975
1976/*
1977 * Take references to capabilities we hold, so that we don't release
1978 * them to the MDS prematurely.
1979 *
1980 * Protected by i_ceph_lock.
1981 */
1982static void __take_cap_refs(struct ceph_inode_info *ci, int got)
 
1983{
 
 
1984	if (got & CEPH_CAP_PIN)
1985		ci->i_pin_ref++;
1986	if (got & CEPH_CAP_FILE_RD)
1987		ci->i_rd_ref++;
1988	if (got & CEPH_CAP_FILE_CACHE)
1989		ci->i_rdcache_ref++;
1990	if (got & CEPH_CAP_FILE_WR)
 
 
 
 
 
 
 
1991		ci->i_wr_ref++;
 
1992	if (got & CEPH_CAP_FILE_BUFFER) {
1993		if (ci->i_wb_ref == 0)
1994			ihold(&ci->vfs_inode);
1995		ci->i_wb_ref++;
1996		dout("__take_cap_refs %p wb %d -> %d (?)\n",
1997		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
1998	}
1999}
2000
2001/*
2002 * Try to grab cap references.  Specify those refs we @want, and the
2003 * minimal set we @need.  Also include the larger offset we are writing
2004 * to (when applicable), and check against max_size here as well.
2005 * Note that caller is responsible for ensuring max_size increases are
2006 * requested from the MDS.
2007 */
2008static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
2009			    int *got, loff_t endoff, int *check_max, int *err)
 
 
 
 
 
 
 
 
 
 
 
 
2010{
2011	struct inode *inode = &ci->vfs_inode;
 
2012	int ret = 0;
2013	int have, implemented;
2014	int file_wanted;
2015
2016	dout("get_cap_refs %p need %s want %s\n", inode,
2017	     ceph_cap_string(need), ceph_cap_string(want));
 
 
2018	spin_lock(&ci->i_ceph_lock);
2019
2020	/* make sure file is actually open */
2021	file_wanted = __ceph_caps_file_wanted(ci);
2022	if ((file_wanted & need) == 0) {
2023		dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
2024		     ceph_cap_string(need), ceph_cap_string(file_wanted));
2025		*err = -EBADF;
2026		ret = 1;
2027		goto out;
2028	}
2029
2030	if (need & CEPH_CAP_FILE_WR) {
 
 
 
 
 
 
 
 
 
 
 
 
 
2031		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2032			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2033			     inode, endoff, ci->i_max_size);
2034			if (endoff > ci->i_wanted_max_size) {
2035				*check_max = 1;
2036				ret = 1;
2037			}
2038			goto out;
2039		}
2040		/*
2041		 * If a sync write is in progress, we must wait, so that we
2042		 * can get a final snapshot value for size+mtime.
2043		 */
2044		if (__ceph_have_pending_cap_snap(ci)) {
2045			dout("get_cap_refs %p cap_snap_pending\n", inode);
2046			goto out;
2047		}
2048	}
2049	have = __ceph_caps_issued(ci, &implemented);
2050
2051	/*
2052	 * disallow writes while a truncate is pending
2053	 */
2054	if (ci->i_truncate_pending)
2055		have &= ~CEPH_CAP_FILE_WR;
2056
2057	if ((have & need) == need) {
2058		/*
2059		 * Look at (implemented & ~have & not) so that we keep waiting
2060		 * on transition from wanted -> needed caps.  This is needed
2061		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2062		 * going before a prior buffered writeback happens.
2063		 */
2064		int not = want & ~(have & need);
2065		int revoking = implemented & ~have;
2066		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2067		     inode, ceph_cap_string(have), ceph_cap_string(not),
2068		     ceph_cap_string(revoking));
2069		if ((revoking & not) == 0) {
2070			*got = need | (have & want);
2071			__take_cap_refs(ci, *got);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2072			ret = 1;
2073		}
2074	} else {
2075		dout("get_cap_refs %p have %s needed %s\n", inode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2076		     ceph_cap_string(have), ceph_cap_string(need));
2077	}
2078out:
 
 
 
2079	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
2080	dout("get_cap_refs %p ret %d got %s\n", inode,
2081	     ret, ceph_cap_string(*got));
2082	return ret;
2083}
2084
2085/*
2086 * Check the offset we are writing up to against our current
2087 * max_size.  If necessary, tell the MDS we want to write to
2088 * a larger offset.
2089 */
2090static void check_max_size(struct inode *inode, loff_t endoff)
2091{
2092	struct ceph_inode_info *ci = ceph_inode(inode);
2093	int check = 0;
2094
2095	/* do we need to explicitly request a larger max_size? */
2096	spin_lock(&ci->i_ceph_lock);
2097	if ((endoff >= ci->i_max_size ||
2098	     endoff > (inode->i_size << 1)) &&
2099	    endoff > ci->i_wanted_max_size) {
2100		dout("write %p at large endoff %llu, req max_size\n",
2101		     inode, endoff);
2102		ci->i_wanted_max_size = endoff;
2103		check = 1;
2104	}
 
 
 
 
 
 
2105	spin_unlock(&ci->i_ceph_lock);
2106	if (check)
2107		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2108}
2109
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2110/*
2111 * Wait for caps, and take cap references.  If we can't get a WR cap
2112 * due to a small max_size, make sure we check_max_size (and possibly
2113 * ask the mds) so we don't get hung up indefinitely.
2114 */
2115int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got,
2116		  loff_t endoff)
2117{
2118	int check_max, ret, err;
 
 
 
 
2119
2120retry:
2121	if (endoff > 0)
2122		check_max_size(&ci->vfs_inode, endoff);
2123	check_max = 0;
2124	err = 0;
2125	ret = wait_event_interruptible(ci->i_cap_wq,
2126				       try_get_cap_refs(ci, need, want,
2127							got, endoff,
2128							&check_max, &err));
2129	if (err)
2130		ret = err;
2131	if (check_max)
2132		goto retry;
2133	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2134}
2135
2136/*
2137 * Take cap refs.  Caller must already know we hold at least one ref
2138 * on the caps in question or we don't know this is safe.
2139 */
2140void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2141{
2142	spin_lock(&ci->i_ceph_lock);
2143	__take_cap_refs(ci, caps);
2144	spin_unlock(&ci->i_ceph_lock);
2145}
2146
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2147/*
2148 * Release cap refs.
2149 *
2150 * If we released the last ref on any given cap, call ceph_check_caps
2151 * to release (or schedule a release).
2152 *
2153 * If we are releasing a WR cap (from a sync write), finalize any affected
2154 * cap_snap, and wake up any waiters.
2155 */
2156void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 
2157{
2158	struct inode *inode = &ci->vfs_inode;
2159	int last = 0, put = 0, flushsnaps = 0, wake = 0;
2160	struct ceph_cap_snap *capsnap;
2161
2162	spin_lock(&ci->i_ceph_lock);
2163	if (had & CEPH_CAP_PIN)
2164		--ci->i_pin_ref;
2165	if (had & CEPH_CAP_FILE_RD)
2166		if (--ci->i_rd_ref == 0)
2167			last++;
2168	if (had & CEPH_CAP_FILE_CACHE)
2169		if (--ci->i_rdcache_ref == 0)
2170			last++;
 
 
 
2171	if (had & CEPH_CAP_FILE_BUFFER) {
2172		if (--ci->i_wb_ref == 0) {
2173			last++;
2174			put++;
2175		}
2176		dout("put_cap_refs %p wb %d -> %d (?)\n",
2177		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
2178	}
2179	if (had & CEPH_CAP_FILE_WR)
2180		if (--ci->i_wr_ref == 0) {
2181			last++;
2182			if (!list_empty(&ci->i_cap_snaps)) {
2183				capsnap = list_first_entry(&ci->i_cap_snaps,
2184						     struct ceph_cap_snap,
2185						     ci_item);
2186				if (capsnap->writing) {
2187					capsnap->writing = 0;
2188					flushsnaps =
2189						__ceph_finish_cap_snap(ci,
2190								       capsnap);
2191					wake = 1;
2192				}
 
 
 
 
 
 
 
2193			}
 
 
 
2194		}
2195	spin_unlock(&ci->i_ceph_lock);
2196
2197	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2198	     last ? " last" : "", put ? " put" : "");
2199
2200	if (last && !flushsnaps)
2201		ceph_check_caps(ci, 0, NULL);
2202	else if (flushsnaps)
2203		ceph_flush_snaps(ci);
2204	if (wake)
2205		wake_up_all(&ci->i_cap_wq);
2206	if (put)
2207		iput(inode);
2208}
2209
 
 
 
 
 
 
 
 
 
 
2210/*
2211 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2212 * context.  Adjust per-snap dirty page accounting as appropriate.
2213 * Once all dirty data for a cap_snap is flushed, flush snapped file
2214 * metadata back to the MDS.  If we dropped the last ref, call
2215 * ceph_check_caps.
2216 */
2217void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2218				struct ceph_snap_context *snapc)
2219{
2220	struct inode *inode = &ci->vfs_inode;
2221	int last = 0;
2222	int complete_capsnap = 0;
2223	int drop_capsnap = 0;
2224	int found = 0;
2225	struct ceph_cap_snap *capsnap = NULL;
 
 
 
 
 
2226
2227	spin_lock(&ci->i_ceph_lock);
2228	ci->i_wrbuffer_ref -= nr;
2229	last = !ci->i_wrbuffer_ref;
 
 
 
2230
2231	if (ci->i_head_snapc == snapc) {
2232		ci->i_wrbuffer_ref_head -= nr;
2233		if (ci->i_wrbuffer_ref_head == 0 &&
2234		    ci->i_dirty_caps == 0 && ci->i_flushing_caps == 0) {
 
 
2235			BUG_ON(!ci->i_head_snapc);
2236			ceph_put_snap_context(ci->i_head_snapc);
2237			ci->i_head_snapc = NULL;
2238		}
2239		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2240		     inode,
2241		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2242		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2243		     last ? " LAST" : "");
2244	} else {
2245		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2246			if (capsnap->context == snapc) {
2247				found = 1;
2248				break;
2249			}
2250		}
2251		BUG_ON(!found);
2252		capsnap->dirty_pages -= nr;
2253		if (capsnap->dirty_pages == 0) {
2254			complete_capsnap = 1;
2255			if (capsnap->dirty == 0)
2256				/* cap writeback completed before we created
2257				 * the cap_snap; no FLUSHSNAP is needed */
2258				drop_capsnap = 1;
 
 
 
 
2259		}
2260		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
2261		     " snap %lld %d/%d -> %d/%d %s%s%s\n",
2262		     inode, capsnap, capsnap->context->seq,
2263		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2264		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
2265		     last ? " (wrbuffer last)" : "",
2266		     complete_capsnap ? " (complete capsnap)" : "",
2267		     drop_capsnap ? " (drop capsnap)" : "");
2268		if (drop_capsnap) {
2269			ceph_put_snap_context(capsnap->context);
2270			list_del(&capsnap->ci_item);
2271			list_del(&capsnap->flushing_item);
2272			ceph_put_cap_snap(capsnap);
2273		}
2274	}
2275
2276	spin_unlock(&ci->i_ceph_lock);
2277
2278	if (last) {
2279		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2280		iput(inode);
2281	} else if (complete_capsnap) {
2282		ceph_flush_snaps(ci);
 
2283		wake_up_all(&ci->i_cap_wq);
 
 
 
2284	}
2285	if (drop_capsnap)
2286		iput(inode);
2287}
2288
2289/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2290 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
2291 * actually be a revocation if it specifies a smaller cap set.)
2292 *
2293 * caller holds s_mutex and i_ceph_lock, we drop both.
2294 *
2295 * return value:
2296 *  0 - ok
2297 *  1 - check_caps on auth cap only (writeback)
2298 *  2 - check_caps (ack revoke)
2299 */
2300static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
2301			     struct ceph_mds_session *session,
2302			     struct ceph_cap *cap,
2303			     struct ceph_buffer *xattr_buf)
2304		__releases(ci->i_ceph_lock)
 
 
 
2305{
2306	struct ceph_inode_info *ci = ceph_inode(inode);
2307	int mds = session->s_mds;
2308	int seq = le32_to_cpu(grant->seq);
2309	int newcaps = le32_to_cpu(grant->caps);
2310	int issued, implemented, used, wanted, dirty;
2311	u64 size = le64_to_cpu(grant->size);
2312	u64 max_size = le64_to_cpu(grant->max_size);
2313	struct timespec mtime, atime, ctime;
2314	int check_caps = 0;
2315	int wake = 0;
2316	int writeback = 0;
2317	int revoked_rdcache = 0;
2318	int queue_invalidate = 0;
 
 
2319
2320	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
2321	     inode, cap, mds, seq, ceph_cap_string(newcaps));
2322	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2323		inode->i_size);
2324
 
2325	/*
2326	 * If CACHE is being revoked, and we have no dirty buffers,
2327	 * try to invalidate (once).  (If there are dirty buffers, we
2328	 * will invalidate _after_ writeback.)
2329	 */
2330	if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
 
2331	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2332	    !ci->i_wrbuffer_ref) {
2333		if (try_nonblocking_invalidate(inode) == 0) {
2334			revoked_rdcache = 1;
2335		} else {
2336			/* there were locked pages.. invalidate later
2337			   in a separate thread. */
2338			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
2339				queue_invalidate = 1;
2340				ci->i_rdcache_revoking = ci->i_rdcache_gen;
2341			}
2342		}
2343	}
2344
2345	/* side effects now are allowed */
 
2346
2347	issued = __ceph_caps_issued(ci, &implemented);
2348	issued |= implemented | __ceph_caps_dirty(ci);
 
 
 
 
 
 
 
 
 
 
 
 
2349
 
2350	cap->cap_gen = session->s_cap_gen;
 
2351
2352	__check_cap_issue(ci, cap, newcaps);
2353
2354	if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
 
 
 
2355		inode->i_mode = le32_to_cpu(grant->mode);
2356		inode->i_uid = le32_to_cpu(grant->uid);
2357		inode->i_gid = le32_to_cpu(grant->gid);
 
2358		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2359		     inode->i_uid, inode->i_gid);
 
2360	}
2361
2362	if ((issued & CEPH_CAP_LINK_EXCL) == 0)
 
2363		set_nlink(inode, le32_to_cpu(grant->nlink));
 
 
 
 
2364
2365	if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
 
2366		int len = le32_to_cpu(grant->xattr_len);
2367		u64 version = le64_to_cpu(grant->xattr_version);
2368
2369		if (version > ci->i_xattrs.version) {
2370			dout(" got new xattrs v%llu on %p len %d\n",
2371			     version, inode, len);
2372			if (ci->i_xattrs.blob)
2373				ceph_buffer_put(ci->i_xattrs.blob);
2374			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2375			ci->i_xattrs.version = version;
 
 
2376		}
2377	}
2378
2379	/* size/ctime/mtime/atime? */
2380	ceph_fill_file_size(inode, issued,
2381			    le32_to_cpu(grant->truncate_seq),
2382			    le64_to_cpu(grant->truncate_size), size);
2383	ceph_decode_timespec(&mtime, &grant->mtime);
2384	ceph_decode_timespec(&atime, &grant->atime);
2385	ceph_decode_timespec(&ctime, &grant->ctime);
2386	ceph_fill_file_time(inode, issued,
2387			    le32_to_cpu(grant->time_warp_seq), &ctime, &mtime,
2388			    &atime);
2389
2390	/* max size increase? */
2391	if (max_size != ci->i_max_size) {
2392		dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
2393		ci->i_max_size = max_size;
2394		if (max_size >= ci->i_wanted_max_size) {
2395			ci->i_wanted_max_size = 0;  /* reset */
2396			ci->i_requested_max_size = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2397		}
2398		wake = 1;
2399	}
2400
2401	/* check cap bits */
2402	wanted = __ceph_caps_wanted(ci);
2403	used = __ceph_caps_used(ci);
2404	dirty = __ceph_caps_dirty(ci);
2405	dout(" my wanted = %s, used = %s, dirty %s\n",
2406	     ceph_cap_string(wanted),
2407	     ceph_cap_string(used),
2408	     ceph_cap_string(dirty));
2409	if (wanted != le32_to_cpu(grant->wanted)) {
2410		dout("mds wanted %s -> %s\n",
2411		     ceph_cap_string(le32_to_cpu(grant->wanted)),
2412		     ceph_cap_string(wanted));
2413		grant->wanted = cpu_to_le32(wanted);
2414	}
2415
2416	cap->seq = seq;
2417
2418	/* file layout may have changed */
2419	ci->i_layout = grant->layout;
 
 
 
 
 
 
 
 
 
 
 
 
2420
2421	/* revocation, grant, or no-op? */
2422	if (cap->issued & ~newcaps) {
2423		int revoking = cap->issued & ~newcaps;
2424
2425		dout("revocation: %s -> %s (revoking %s)\n",
2426		     ceph_cap_string(cap->issued),
2427		     ceph_cap_string(newcaps),
2428		     ceph_cap_string(revoking));
2429		if (revoking & used & CEPH_CAP_FILE_BUFFER)
2430			writeback = 1;  /* initiate writeback; will delay ack */
2431		else if (revoking == CEPH_CAP_FILE_CACHE &&
2432			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
2433			 queue_invalidate)
 
2434			; /* do nothing yet, invalidation will be queued */
2435		else if (cap == ci->i_auth_cap)
2436			check_caps = 1; /* check auth cap only */
2437		else
2438			check_caps = 2; /* check all caps */
2439		cap->issued = newcaps;
2440		cap->implemented |= newcaps;
2441	} else if (cap->issued == newcaps) {
2442		dout("caps unchanged: %s -> %s\n",
2443		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
2444	} else {
2445		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
2446		     ceph_cap_string(newcaps));
 
 
 
 
 
2447		cap->issued = newcaps;
2448		cap->implemented |= newcaps; /* add bits only, to
2449					      * avoid stepping on a
2450					      * pending revocation */
2451		wake = 1;
2452	}
2453	BUG_ON(cap->issued & ~cap->implemented);
2454
2455	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2456	if (writeback)
2457		/*
2458		 * queue inode for writeback: we can't actually call
2459		 * filemap_write_and_wait, etc. from message handler
2460		 * context.
2461		 */
2462		ceph_queue_writeback(inode);
2463	if (queue_invalidate)
2464		ceph_queue_invalidate(inode);
 
 
2465	if (wake)
2466		wake_up_all(&ci->i_cap_wq);
2467
2468	if (check_caps == 1)
2469		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
2470				session);
2471	else if (check_caps == 2)
2472		ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
2473	else
2474		mutex_unlock(&session->s_mutex);
2475}
2476
2477/*
2478 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
2479 * MDS has been safely committed.
2480 */
2481static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
2482				 struct ceph_mds_caps *m,
2483				 struct ceph_mds_session *session,
2484				 struct ceph_cap *cap)
2485	__releases(ci->i_ceph_lock)
2486{
2487	struct ceph_inode_info *ci = ceph_inode(inode);
2488	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
 
 
2489	unsigned seq = le32_to_cpu(m->seq);
2490	int dirty = le32_to_cpu(m->dirty);
2491	int cleaned = 0;
2492	int drop = 0;
2493	int i;
 
 
 
 
 
 
 
 
 
 
2494
2495	for (i = 0; i < CEPH_CAP_BITS; i++)
2496		if ((dirty & (1 << i)) &&
2497		    flush_tid == ci->i_cap_flush_tid[i])
2498			cleaned |= 1 << i;
 
 
 
 
 
 
 
 
 
 
 
 
 
2499
2500	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
2501	     " flushing %s -> %s\n",
2502	     inode, session->s_mds, seq, ceph_cap_string(dirty),
2503	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
2504	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
2505
2506	if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
2507		goto out;
2508
2509	ci->i_flushing_caps &= ~cleaned;
2510
2511	spin_lock(&mdsc->cap_dirty_lock);
 
 
 
 
2512	if (ci->i_flushing_caps == 0) {
2513		list_del_init(&ci->i_flushing_item);
2514		if (!list_empty(&session->s_cap_flushing))
2515			dout(" mds%d still flushing cap on %p\n",
2516			     session->s_mds,
2517			     &list_entry(session->s_cap_flushing.next,
2518					 struct ceph_inode_info,
2519					 i_flushing_item)->vfs_inode);
 
 
 
2520		mdsc->num_cap_flushing--;
2521		wake_up_all(&mdsc->cap_flushing_wq);
2522		dout(" inode %p now !flushing\n", inode);
2523
2524		if (ci->i_dirty_caps == 0) {
2525			dout(" inode %p now clean\n", inode);
2526			BUG_ON(!list_empty(&ci->i_dirty_item));
2527			drop = 1;
2528			if (ci->i_wrbuffer_ref_head == 0) {
 
2529				BUG_ON(!ci->i_head_snapc);
2530				ceph_put_snap_context(ci->i_head_snapc);
2531				ci->i_head_snapc = NULL;
2532			}
2533		} else {
2534			BUG_ON(list_empty(&ci->i_dirty_item));
2535		}
2536	}
2537	spin_unlock(&mdsc->cap_dirty_lock);
2538	wake_up_all(&ci->i_cap_wq);
2539
2540out:
2541	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
2542	if (drop)
2543		iput(inode);
2544}
2545
2546/*
2547 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
2548 * throw away our cap_snap.
2549 *
2550 * Caller hold s_mutex.
2551 */
2552static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
2553				     struct ceph_mds_caps *m,
2554				     struct ceph_mds_session *session)
2555{
2556	struct ceph_inode_info *ci = ceph_inode(inode);
 
2557	u64 follows = le64_to_cpu(m->snap_follows);
2558	struct ceph_cap_snap *capsnap;
2559	int drop = 0;
 
 
2560
2561	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
2562	     inode, ci, session->s_mds, follows);
2563
2564	spin_lock(&ci->i_ceph_lock);
2565	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2566		if (capsnap->follows == follows) {
2567			if (capsnap->flush_tid != flush_tid) {
2568				dout(" cap_snap %p follows %lld tid %lld !="
2569				     " %lld\n", capsnap, follows,
2570				     flush_tid, capsnap->flush_tid);
2571				break;
2572			}
2573			WARN_ON(capsnap->dirty_pages || capsnap->writing);
2574			dout(" removing %p cap_snap %p follows %lld\n",
2575			     inode, capsnap, follows);
2576			ceph_put_snap_context(capsnap->context);
2577			list_del(&capsnap->ci_item);
2578			list_del(&capsnap->flushing_item);
2579			ceph_put_cap_snap(capsnap);
2580			drop = 1;
2581			break;
2582		} else {
2583			dout(" skipping cap_snap %p follows %lld\n",
2584			     capsnap, capsnap->follows);
2585		}
2586	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2587	spin_unlock(&ci->i_ceph_lock);
2588	if (drop)
 
 
 
 
 
 
2589		iput(inode);
 
2590}
2591
2592/*
2593 * Handle TRUNC from MDS, indicating file truncation.
2594 *
2595 * caller hold s_mutex.
2596 */
2597static void handle_cap_trunc(struct inode *inode,
2598			     struct ceph_mds_caps *trunc,
2599			     struct ceph_mds_session *session)
2600	__releases(ci->i_ceph_lock)
2601{
2602	struct ceph_inode_info *ci = ceph_inode(inode);
2603	int mds = session->s_mds;
2604	int seq = le32_to_cpu(trunc->seq);
2605	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
2606	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
2607	u64 size = le64_to_cpu(trunc->size);
2608	int implemented = 0;
2609	int dirty = __ceph_caps_dirty(ci);
2610	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
2611	int queue_trunc = 0;
 
 
2612
2613	issued |= implemented | dirty;
2614
2615	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
2616	     inode, mds, seq, truncate_size, truncate_seq);
2617	queue_trunc = ceph_fill_file_size(inode, issued,
2618					  truncate_seq, truncate_size, size);
2619	spin_unlock(&ci->i_ceph_lock);
2620
2621	if (queue_trunc)
2622		ceph_queue_vmtruncate(inode);
2623}
2624
2625/*
2626 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
2627 * different one.  If we are the most recent migration we've seen (as
2628 * indicated by mseq), make note of the migrating cap bits for the
2629 * duration (until we see the corresponding IMPORT).
2630 *
2631 * caller holds s_mutex
2632 */
2633static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
2634			      struct ceph_mds_session *session,
2635			      int *open_target_sessions)
2636{
2637	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 
 
2638	struct ceph_inode_info *ci = ceph_inode(inode);
2639	int mds = session->s_mds;
2640	unsigned mseq = le32_to_cpu(ex->migrate_seq);
2641	struct ceph_cap *cap = NULL, *t;
2642	struct rb_node *p;
2643	int remember = 1;
2644
2645	dout("handle_cap_export inode %p ci %p mds%d mseq %d\n",
2646	     inode, ci, mds, mseq);
 
 
 
 
 
 
 
2647
 
 
 
2648	spin_lock(&ci->i_ceph_lock);
 
 
 
2649
2650	/* make sure we haven't seen a higher mseq */
2651	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
2652		t = rb_entry(p, struct ceph_cap, ci_node);
2653		if (ceph_seq_cmp(t->mseq, mseq) > 0) {
2654			dout(" higher mseq on cap from mds%d\n",
2655			     t->session->s_mds);
2656			remember = 0;
2657		}
2658		if (t->session->s_mds == mds)
2659			cap = t;
2660	}
2661
2662	if (cap) {
2663		if (remember) {
2664			/* make note */
2665			ci->i_cap_exporting_mds = mds;
2666			ci->i_cap_exporting_mseq = mseq;
2667			ci->i_cap_exporting_issued = cap->issued;
2668
2669			/*
2670			 * make sure we have open sessions with all possible
2671			 * export targets, so that we get the matching IMPORT
2672			 */
2673			*open_target_sessions = 1;
2674
2675			/*
2676			 * we can't flush dirty caps that we've seen the
2677			 * EXPORT but no IMPORT for
2678			 */
2679			spin_lock(&mdsc->cap_dirty_lock);
2680			if (!list_empty(&ci->i_dirty_item)) {
2681				dout(" moving %p to cap_dirty_migrating\n",
2682				     inode);
2683				list_move(&ci->i_dirty_item,
2684					  &mdsc->cap_dirty_migrating);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2685			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2686			spin_unlock(&mdsc->cap_dirty_lock);
2687		}
2688		__ceph_remove_cap(cap);
 
 
2689	}
2690	/* else, we already released it */
2691
2692	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2693}
2694
2695/*
2696 * Handle cap IMPORT.  If there are temp bits from an older EXPORT,
2697 * clean them up.
2698 *
2699 * caller holds s_mutex.
2700 */
2701static void handle_cap_import(struct ceph_mds_client *mdsc,
2702			      struct inode *inode, struct ceph_mds_caps *im,
 
2703			      struct ceph_mds_session *session,
2704			      void *snaptrace, int snaptrace_len)
2705{
2706	struct ceph_inode_info *ci = ceph_inode(inode);
 
2707	int mds = session->s_mds;
2708	unsigned issued = le32_to_cpu(im->caps);
 
2709	unsigned wanted = le32_to_cpu(im->wanted);
2710	unsigned seq = le32_to_cpu(im->seq);
2711	unsigned mseq = le32_to_cpu(im->migrate_seq);
2712	u64 realmino = le64_to_cpu(im->realm);
2713	u64 cap_id = le64_to_cpu(im->cap_id);
 
 
2714
2715	if (ci->i_cap_exporting_mds >= 0 &&
2716	    ceph_seq_cmp(ci->i_cap_exporting_mseq, mseq) < 0) {
2717		dout("handle_cap_import inode %p ci %p mds%d mseq %d"
2718		     " - cleared exporting from mds%d\n",
2719		     inode, ci, mds, mseq,
2720		     ci->i_cap_exporting_mds);
2721		ci->i_cap_exporting_issued = 0;
2722		ci->i_cap_exporting_mseq = 0;
2723		ci->i_cap_exporting_mds = -1;
2724
2725		spin_lock(&mdsc->cap_dirty_lock);
2726		if (!list_empty(&ci->i_dirty_item)) {
2727			dout(" moving %p back to cap_dirty\n", inode);
2728			list_move(&ci->i_dirty_item, &mdsc->cap_dirty);
 
 
 
 
 
 
2729		}
2730		spin_unlock(&mdsc->cap_dirty_lock);
2731	} else {
2732		dout("handle_cap_import inode %p ci %p mds%d mseq %d\n",
2733		     inode, ci, mds, mseq);
 
 
2734	}
2735
2736	down_write(&mdsc->snap_rwsem);
2737	ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
2738			       false);
2739	downgrade_write(&mdsc->snap_rwsem);
2740	ceph_add_cap(inode, session, cap_id, -1,
2741		     issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
2742		     NULL /* no caps context */);
2743	kick_flushing_inode_caps(mdsc, session, inode);
2744	up_read(&mdsc->snap_rwsem);
2745
2746	/* make sure we re-request max_size, if necessary */
2747	spin_lock(&ci->i_ceph_lock);
2748	ci->i_requested_max_size = 0;
2749	spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2750}
2751
2752/*
2753 * Handle a caps message from the MDS.
2754 *
2755 * Identify the appropriate session, inode, and call the right handler
2756 * based on the cap op.
2757 */
2758void ceph_handle_caps(struct ceph_mds_session *session,
2759		      struct ceph_msg *msg)
2760{
2761	struct ceph_mds_client *mdsc = session->s_mdsc;
2762	struct super_block *sb = mdsc->fsc->sb;
2763	struct inode *inode;
2764	struct ceph_inode_info *ci;
2765	struct ceph_cap *cap;
2766	struct ceph_mds_caps *h;
2767	int mds = session->s_mds;
 
2768	int op;
 
2769	u32 seq, mseq;
2770	struct ceph_vino vino;
2771	u64 cap_id;
2772	u64 size, max_size;
2773	u64 tid;
2774	void *snaptrace;
2775	size_t snaptrace_len;
2776	void *flock;
2777	u32 flock_len;
2778	int open_target_sessions = 0;
2779
2780	dout("handle_caps from mds%d\n", mds);
2781
2782	/* decode */
2783	tid = le64_to_cpu(msg->hdr.tid);
2784	if (msg->front.iov_len < sizeof(*h))
2785		goto bad;
2786	h = msg->front.iov_base;
2787	op = le32_to_cpu(h->op);
2788	vino.ino = le64_to_cpu(h->ino);
2789	vino.snap = CEPH_NOSNAP;
2790	cap_id = le64_to_cpu(h->cap_id);
2791	seq = le32_to_cpu(h->seq);
2792	mseq = le32_to_cpu(h->migrate_seq);
2793	size = le64_to_cpu(h->size);
2794	max_size = le64_to_cpu(h->max_size);
2795
2796	snaptrace = h + 1;
2797	snaptrace_len = le32_to_cpu(h->snap_trace_len);
 
2798
2799	if (le16_to_cpu(msg->hdr.version) >= 2) {
2800		void *p, *end;
2801
2802		p = snaptrace + snaptrace_len;
2803		end = msg->front.iov_base + msg->front.iov_len;
2804		ceph_decode_32_safe(&p, end, flock_len, bad);
2805		flock = p;
2806	} else {
2807		flock = NULL;
2808		flock_len = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2809	}
2810
 
 
 
 
 
 
2811	mutex_lock(&session->s_mutex);
2812	session->s_seq++;
2813	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
2814	     (unsigned)seq);
2815
2816	/* lookup ino */
2817	inode = ceph_find_inode(sb, vino);
2818	ci = ceph_inode(inode);
2819	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
2820	     vino.snap, inode);
2821	if (!inode) {
2822		dout(" i don't have ino %llx\n", vino.ino);
2823
2824		if (op == CEPH_CAP_OP_IMPORT)
2825			__queue_cap_release(session, vino.ino, cap_id,
2826					    mseq, seq);
 
 
 
 
 
 
 
 
 
2827		goto flush_cap_releases;
2828	}
2829
2830	/* these will work even if we don't have a cap yet */
2831	switch (op) {
2832	case CEPH_CAP_OP_FLUSHSNAP_ACK:
2833		handle_cap_flushsnap_ack(inode, tid, h, session);
 
2834		goto done;
2835
2836	case CEPH_CAP_OP_EXPORT:
2837		handle_cap_export(inode, h, session, &open_target_sessions);
2838		goto done;
2839
2840	case CEPH_CAP_OP_IMPORT:
2841		handle_cap_import(mdsc, inode, h, session,
2842				  snaptrace, snaptrace_len);
2843		ceph_check_caps(ceph_inode(inode), 0, session);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2844		goto done_unlocked;
2845	}
2846
2847	/* the rest require a cap */
2848	spin_lock(&ci->i_ceph_lock);
2849	cap = __get_cap_for_mds(ceph_inode(inode), mds);
2850	if (!cap) {
2851		dout(" no cap on %p ino %llx.%llx from mds%d\n",
2852		     inode, ceph_ino(inode), ceph_snap(inode), mds);
 
2853		spin_unlock(&ci->i_ceph_lock);
2854		goto flush_cap_releases;
2855	}
2856
2857	/* note that each of these drops i_ceph_lock for us */
2858	switch (op) {
2859	case CEPH_CAP_OP_REVOKE:
2860	case CEPH_CAP_OP_GRANT:
2861		handle_cap_grant(inode, h, session, cap, msg->middle);
 
 
 
2862		goto done_unlocked;
2863
2864	case CEPH_CAP_OP_FLUSH_ACK:
2865		handle_cap_flush_ack(inode, tid, h, session, cap);
 
2866		break;
2867
2868	case CEPH_CAP_OP_TRUNC:
2869		handle_cap_trunc(inode, h, session);
 
 
 
2870		break;
2871
2872	default:
2873		spin_unlock(&ci->i_ceph_lock);
2874		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
2875		       ceph_cap_op_name(op));
2876	}
2877
2878	goto done;
 
 
 
 
 
 
2879
2880flush_cap_releases:
2881	/*
2882	 * send any full release message to try to move things
2883	 * along for the mds (who clearly thinks we still have this
2884	 * cap).
2885	 */
2886	ceph_add_cap_releases(mdsc, session);
2887	ceph_send_cap_releases(mdsc, session);
2888
2889done:
2890	mutex_unlock(&session->s_mutex);
2891done_unlocked:
2892	if (inode)
2893		iput(inode);
2894	if (open_target_sessions)
2895		ceph_mdsc_open_export_target_sessions(mdsc, session);
2896	return;
2897
2898bad:
2899	pr_err("ceph_handle_caps: corrupt message\n");
2900	ceph_msg_dump(msg);
2901	return;
2902}
2903
2904/*
2905 * Delayed work handler to process end of delayed cap release LRU list.
2906 */
2907void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
2908{
 
2909	struct ceph_inode_info *ci;
2910	int flags = CHECK_CAPS_NODELAY;
2911
2912	dout("check_delayed_caps\n");
2913	while (1) {
2914		spin_lock(&mdsc->cap_delay_lock);
2915		if (list_empty(&mdsc->cap_delay_list))
2916			break;
2917		ci = list_first_entry(&mdsc->cap_delay_list,
2918				      struct ceph_inode_info,
2919				      i_cap_delay_list);
2920		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
2921		    time_before(jiffies, ci->i_hold_caps_max))
2922			break;
2923		list_del_init(&ci->i_cap_delay_list);
2924		spin_unlock(&mdsc->cap_delay_lock);
2925		dout("check_delayed_caps on %p\n", &ci->vfs_inode);
2926		ceph_check_caps(ci, flags, NULL);
 
 
 
 
 
 
 
2927	}
2928	spin_unlock(&mdsc->cap_delay_lock);
2929}
2930
2931/*
2932 * Flush all dirty caps to the mds
2933 */
2934void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
2935{
 
2936	struct ceph_inode_info *ci;
2937	struct inode *inode;
2938
2939	dout("flush_dirty_caps\n");
2940	spin_lock(&mdsc->cap_dirty_lock);
2941	while (!list_empty(&mdsc->cap_dirty)) {
2942		ci = list_first_entry(&mdsc->cap_dirty, struct ceph_inode_info,
2943				      i_dirty_item);
2944		inode = &ci->vfs_inode;
2945		ihold(inode);
2946		dout("flush_dirty_caps %p\n", inode);
2947		spin_unlock(&mdsc->cap_dirty_lock);
2948		ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH, NULL);
2949		iput(inode);
2950		spin_lock(&mdsc->cap_dirty_lock);
2951	}
2952	spin_unlock(&mdsc->cap_dirty_lock);
2953	dout("flush_dirty_caps done\n");
2954}
2955
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2956/*
2957 * Drop open file reference.  If we were the last open file,
2958 * we may need to release capabilities to the MDS (or schedule
2959 * their delayed release).
2960 */
2961void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
2962{
2963	struct inode *inode = &ci->vfs_inode;
2964	int last = 0;
2965
2966	spin_lock(&ci->i_ceph_lock);
2967	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
2968	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
2969	BUG_ON(ci->i_nr_by_mode[fmode] == 0);
2970	if (--ci->i_nr_by_mode[fmode] == 0)
2971		last++;
 
2972	spin_unlock(&ci->i_ceph_lock);
 
2973
2974	if (last && ci->i_vino.snap == CEPH_NOSNAP)
2975		ceph_check_caps(ci, 0, NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2976}
2977
2978/*
2979 * Helpers for embedding cap and dentry lease releases into mds
2980 * requests.
2981 *
2982 * @force is used by dentry_release (below) to force inclusion of a
2983 * record for the directory inode, even when there aren't any caps to
2984 * drop.
2985 */
2986int ceph_encode_inode_release(void **p, struct inode *inode,
2987			      int mds, int drop, int unless, int force)
2988{
2989	struct ceph_inode_info *ci = ceph_inode(inode);
2990	struct ceph_cap *cap;
2991	struct ceph_mds_request_release *rel = *p;
2992	int used, dirty;
2993	int ret = 0;
2994
2995	spin_lock(&ci->i_ceph_lock);
2996	used = __ceph_caps_used(ci);
2997	dirty = __ceph_caps_dirty(ci);
2998
2999	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
3000	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
3001	     ceph_cap_string(unless));
3002
3003	/* only drop unused, clean caps */
3004	drop &= ~(used | dirty);
3005
3006	cap = __get_cap_for_mds(ci, mds);
3007	if (cap && __cap_is_valid(cap)) {
3008		if (force ||
3009		    ((cap->issued & drop) &&
3010		     (cap->issued & unless) == 0)) {
3011			if ((cap->issued & drop) &&
3012			    (cap->issued & unless) == 0) {
3013				dout("encode_inode_release %p cap %p %s -> "
3014				     "%s\n", inode, cap,
 
 
 
 
 
 
 
 
 
 
3015				     ceph_cap_string(cap->issued),
3016				     ceph_cap_string(cap->issued & ~drop));
 
 
 
3017				cap->issued &= ~drop;
3018				cap->implemented &= ~drop;
3019				if (ci->i_ceph_flags & CEPH_I_NODELAY) {
3020					int wanted = __ceph_caps_wanted(ci);
3021					dout("  wanted %s -> %s (act %s)\n",
3022					     ceph_cap_string(cap->mds_wanted),
3023					     ceph_cap_string(cap->mds_wanted &
3024							     ~wanted),
3025					     ceph_cap_string(wanted));
3026					cap->mds_wanted &= wanted;
3027				}
3028			} else {
3029				dout("encode_inode_release %p cap %p %s"
3030				     " (force)\n", inode, cap,
3031				     ceph_cap_string(cap->issued));
3032			}
3033
3034			rel->ino = cpu_to_le64(ceph_ino(inode));
3035			rel->cap_id = cpu_to_le64(cap->cap_id);
3036			rel->seq = cpu_to_le32(cap->seq);
3037			rel->issue_seq = cpu_to_le32(cap->issue_seq),
3038			rel->mseq = cpu_to_le32(cap->mseq);
3039			rel->caps = cpu_to_le32(cap->issued);
3040			rel->wanted = cpu_to_le32(cap->mds_wanted);
3041			rel->dname_len = 0;
3042			rel->dname_seq = 0;
3043			*p += sizeof(*rel);
3044			ret = 1;
3045		} else {
3046			dout("encode_inode_release %p cap %p %s\n",
3047			     inode, cap, ceph_cap_string(cap->issued));
3048		}
3049	}
3050	spin_unlock(&ci->i_ceph_lock);
3051	return ret;
3052}
3053
3054int ceph_encode_dentry_release(void **p, struct dentry *dentry,
 
3055			       int mds, int drop, int unless)
3056{
3057	struct inode *dir = dentry->d_parent->d_inode;
3058	struct ceph_mds_request_release *rel = *p;
3059	struct ceph_dentry_info *di = ceph_dentry(dentry);
3060	int force = 0;
3061	int ret;
3062
3063	/*
3064	 * force an record for the directory caps if we have a dentry lease.
3065	 * this is racy (can't take i_ceph_lock and d_lock together), but it
3066	 * doesn't have to be perfect; the mds will revoke anything we don't
3067	 * release.
3068	 */
3069	spin_lock(&dentry->d_lock);
3070	if (di->lease_session && di->lease_session->s_mds == mds)
3071		force = 1;
 
 
 
 
3072	spin_unlock(&dentry->d_lock);
3073
3074	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
 
3075
3076	spin_lock(&dentry->d_lock);
3077	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
3078		dout("encode_dentry_release %p mds%d seq %d\n",
3079		     dentry, mds, (int)di->lease_seq);
3080		rel->dname_len = cpu_to_le32(dentry->d_name.len);
3081		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
3082		*p += dentry->d_name.len;
3083		rel->dname_seq = cpu_to_le32(di->lease_seq);
3084		__ceph_mdsc_drop_dentry_lease(dentry);
3085	}
3086	spin_unlock(&dentry->d_lock);
3087	return ret;
3088}
v5.9
   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->vfs_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->vfs_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->vfs_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->vfs_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->vfs_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->vfs_inode.i_mode)) {
 587			dout(" marking %p NOT complete\n", &ci->vfs_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->vfs_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 */
 605static void 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	spin_lock(&session->s_gen_ttl_lock);
 649	gen = session->s_cap_gen;
 650	spin_unlock(&session->s_gen_ttl_lock);
 
 
 
 651
 
 
 652	cap = __get_cap_for_mds(ci, mds);
 653	if (!cap) {
 654		cap = *new_cap;
 655		*new_cap = NULL;
 
 
 
 
 
 
 
 
 656
 657		cap->issued = 0;
 658		cap->implemented = 0;
 659		cap->mds = mds;
 660		cap->mds_wanted = 0;
 661		cap->mseq = 0;
 662
 663		cap->ci = ci;
 664		__insert_cap_node(ci, cap);
 665
 
 
 
 
 
 
 
 666		/* add to session cap list */
 667		cap->session = session;
 668		spin_lock(&session->s_cap_lock);
 669		list_add_tail(&cap->session_caps, &session->s_caps);
 670		session->s_nr_caps++;
 671		atomic64_inc(&mdsc->metric.total_caps);
 672		spin_unlock(&session->s_cap_lock);
 673	} else {
 674		spin_lock(&session->s_cap_lock);
 675		list_move_tail(&cap->session_caps, &session->s_caps);
 676		spin_unlock(&session->s_cap_lock);
 
 
 677
 678		if (cap->cap_gen < gen)
 679			cap->issued = cap->implemented = CEPH_CAP_PIN;
 680
 681		/*
 682		 * auth mds of the inode changed. we received the cap export
 683		 * message, but still haven't received the cap import message.
 684		 * handle_cap_export() updated the new auth MDS' cap.
 685		 *
 686		 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing
 687		 * a message that was send before the cap import message. So
 688		 * don't remove caps.
 689		 */
 690		if (ceph_seq_cmp(seq, cap->seq) <= 0) {
 691			WARN_ON(cap != ci->i_auth_cap);
 692			WARN_ON(cap->cap_id != cap_id);
 693			seq = cap->seq;
 694			mseq = cap->mseq;
 695			issued |= cap->issued;
 696			flags |= CEPH_CAP_FLAG_AUTH;
 697		}
 698	}
 699
 700	if (!ci->i_snap_realm ||
 701	    ((flags & CEPH_CAP_FLAG_AUTH) &&
 702	     realmino != (u64)-1 && ci->i_snap_realm->ino != realmino)) {
 703		/*
 704		 * add this inode to the appropriate snap realm
 705		 */
 706		struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
 707							       realmino);
 708		if (realm) {
 709			struct ceph_snap_realm *oldrealm = ci->i_snap_realm;
 710			if (oldrealm) {
 711				spin_lock(&oldrealm->inodes_with_caps_lock);
 712				list_del_init(&ci->i_snap_realm_item);
 713				spin_unlock(&oldrealm->inodes_with_caps_lock);
 714			}
 715
 716			spin_lock(&realm->inodes_with_caps_lock);
 
 717			list_add(&ci->i_snap_realm_item,
 718				 &realm->inodes_with_caps);
 719			ci->i_snap_realm = realm;
 720			if (realm->ino == ci->i_vino.ino)
 721				realm->inode = inode;
 722			spin_unlock(&realm->inodes_with_caps_lock);
 723
 724			if (oldrealm)
 725				ceph_put_snap_realm(mdsc, oldrealm);
 726		} else {
 727			pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
 728			       realmino);
 729			WARN_ON(!realm);
 730		}
 731	}
 732
 733	__check_cap_issue(ci, cap, issued);
 734
 735	/*
 736	 * If we are issued caps we don't want, or the mds' wanted
 737	 * value appears to be off, queue a check so we'll release
 738	 * later and/or update the mds wanted value.
 739	 */
 740	actual_wanted = __ceph_caps_wanted(ci);
 741	if ((wanted & ~actual_wanted) ||
 742	    (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
 743		dout(" issued %s, mds wanted %s, actual %s, queueing\n",
 744		     ceph_cap_string(issued), ceph_cap_string(wanted),
 745		     ceph_cap_string(actual_wanted));
 746		__cap_delay_requeue(mdsc, ci);
 747	}
 748
 749	if (flags & CEPH_CAP_FLAG_AUTH) {
 750		if (!ci->i_auth_cap ||
 751		    ceph_seq_cmp(ci->i_auth_cap->mseq, mseq) < 0) {
 752			if (ci->i_auth_cap &&
 753			    ci->i_auth_cap->session != cap->session)
 754				change_auth_cap_ses(ci, cap->session);
 755			ci->i_auth_cap = cap;
 756			cap->mds_wanted = wanted;
 757		}
 758	} else {
 759		WARN_ON(ci->i_auth_cap == cap);
 760	}
 761
 762	dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
 763	     inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
 764	     ceph_cap_string(issued|cap->issued), seq, mds);
 765	cap->cap_id = cap_id;
 766	cap->issued = issued;
 767	cap->implemented |= issued;
 768	if (ceph_seq_cmp(mseq, cap->mseq) > 0)
 769		cap->mds_wanted = wanted;
 770	else
 771		cap->mds_wanted |= wanted;
 772	cap->seq = seq;
 773	cap->issue_seq = seq;
 774	cap->mseq = mseq;
 775	cap->cap_gen = gen;
 
 
 
 
 
 
 776}
 777
 778/*
 779 * Return true if cap has not timed out and belongs to the current
 780 * generation of the MDS session (i.e. has not gone 'stale' due to
 781 * us losing touch with the mds).
 782 */
 783static int __cap_is_valid(struct ceph_cap *cap)
 784{
 785	unsigned long ttl;
 786	u32 gen;
 787
 788	spin_lock(&cap->session->s_gen_ttl_lock);
 789	gen = cap->session->s_cap_gen;
 790	ttl = cap->session->s_cap_ttl;
 791	spin_unlock(&cap->session->s_gen_ttl_lock);
 792
 793	if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
 794		dout("__cap_is_valid %p cap %p issued %s "
 795		     "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
 796		     cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
 797		return 0;
 798	}
 799
 800	return 1;
 801}
 802
 803/*
 804 * Return set of valid cap bits issued to us.  Note that caps time
 805 * out, and may be invalidated in bulk if the client session times out
 806 * and session->s_cap_gen is bumped.
 807 */
 808int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
 809{
 810	int have = ci->i_snap_caps;
 811	struct ceph_cap *cap;
 812	struct rb_node *p;
 813
 814	if (implemented)
 815		*implemented = 0;
 816	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 817		cap = rb_entry(p, struct ceph_cap, ci_node);
 818		if (!__cap_is_valid(cap))
 819			continue;
 820		dout("__ceph_caps_issued %p cap %p issued %s\n",
 821		     &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
 822		have |= cap->issued;
 823		if (implemented)
 824			*implemented |= cap->implemented;
 825	}
 826	/*
 827	 * exclude caps issued by non-auth MDS, but are been revoking
 828	 * by the auth MDS. The non-auth MDS should be revoking/exporting
 829	 * these caps, but the message is delayed.
 830	 */
 831	if (ci->i_auth_cap) {
 832		cap = ci->i_auth_cap;
 833		have &= ~cap->implemented | cap->issued;
 834	}
 835	return have;
 836}
 837
 838/*
 839 * Get cap bits issued by caps other than @ocap
 840 */
 841int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
 842{
 843	int have = ci->i_snap_caps;
 844	struct ceph_cap *cap;
 845	struct rb_node *p;
 846
 847	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 848		cap = rb_entry(p, struct ceph_cap, ci_node);
 849		if (cap == ocap)
 850			continue;
 851		if (!__cap_is_valid(cap))
 852			continue;
 853		have |= cap->issued;
 854	}
 855	return have;
 856}
 857
 858/*
 859 * Move a cap to the end of the LRU (oldest caps at list head, newest
 860 * at list tail).
 861 */
 862static void __touch_cap(struct ceph_cap *cap)
 863{
 864	struct ceph_mds_session *s = cap->session;
 865
 866	spin_lock(&s->s_cap_lock);
 867	if (!s->s_cap_iterator) {
 868		dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
 869		     s->s_mds);
 870		list_move_tail(&cap->session_caps, &s->s_caps);
 871	} else {
 872		dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
 873		     &cap->ci->vfs_inode, cap, s->s_mds);
 874	}
 875	spin_unlock(&s->s_cap_lock);
 876}
 877
 878/*
 879 * Check if we hold the given mask.  If so, move the cap(s) to the
 880 * front of their respective LRUs.  (This is the preferred way for
 881 * callers to check for caps they want.)
 882 */
 883int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
 884{
 885	struct ceph_cap *cap;
 886	struct rb_node *p;
 887	int have = ci->i_snap_caps;
 888
 889	if ((have & mask) == mask) {
 890		dout("__ceph_caps_issued_mask ino 0x%llx snap issued %s"
 891		     " (mask %s)\n", ceph_ino(&ci->vfs_inode),
 892		     ceph_cap_string(have),
 893		     ceph_cap_string(mask));
 894		return 1;
 895	}
 896
 897	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 898		cap = rb_entry(p, struct ceph_cap, ci_node);
 899		if (!__cap_is_valid(cap))
 900			continue;
 901		if ((cap->issued & mask) == mask) {
 902			dout("__ceph_caps_issued_mask ino 0x%llx cap %p issued %s"
 903			     " (mask %s)\n", ceph_ino(&ci->vfs_inode), cap,
 904			     ceph_cap_string(cap->issued),
 905			     ceph_cap_string(mask));
 906			if (touch)
 907				__touch_cap(cap);
 908			return 1;
 909		}
 910
 911		/* does a combination of caps satisfy mask? */
 912		have |= cap->issued;
 913		if ((have & mask) == mask) {
 914			dout("__ceph_caps_issued_mask ino 0x%llx combo issued %s"
 915			     " (mask %s)\n", ceph_ino(&ci->vfs_inode),
 916			     ceph_cap_string(cap->issued),
 917			     ceph_cap_string(mask));
 918			if (touch) {
 919				struct rb_node *q;
 920
 921				/* touch this + preceding caps */
 922				__touch_cap(cap);
 923				for (q = rb_first(&ci->i_caps); q != p;
 924				     q = rb_next(q)) {
 925					cap = rb_entry(q, struct ceph_cap,
 926						       ci_node);
 927					if (!__cap_is_valid(cap))
 928						continue;
 929					if (cap->issued & mask)
 930						__touch_cap(cap);
 931				}
 932			}
 933			return 1;
 934		}
 935	}
 936
 937	return 0;
 938}
 939
 940int __ceph_caps_issued_mask_metric(struct ceph_inode_info *ci, int mask,
 941				   int touch)
 942{
 943	struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
 944	int r;
 945
 946	r = __ceph_caps_issued_mask(ci, mask, touch);
 947	if (r)
 948		ceph_update_cap_hit(&fsc->mdsc->metric);
 949	else
 950		ceph_update_cap_mis(&fsc->mdsc->metric);
 951	return r;
 952}
 953
 954/*
 955 * Return true if mask caps are currently being revoked by an MDS.
 956 */
 957int __ceph_caps_revoking_other(struct ceph_inode_info *ci,
 958			       struct ceph_cap *ocap, int mask)
 959{
 
 960	struct ceph_cap *cap;
 961	struct rb_node *p;
 
 962
 
 963	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
 964		cap = rb_entry(p, struct ceph_cap, ci_node);
 965		if (cap != ocap &&
 966		    (cap->implemented & ~cap->issued & mask))
 967			return 1;
 
 
 968	}
 969	return 0;
 970}
 971
 972int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
 973{
 974	struct inode *inode = &ci->vfs_inode;
 975	int ret;
 976
 977	spin_lock(&ci->i_ceph_lock);
 978	ret = __ceph_caps_revoking_other(ci, NULL, mask);
 979	spin_unlock(&ci->i_ceph_lock);
 980	dout("ceph_caps_revoking %p %s = %d\n", inode,
 981	     ceph_cap_string(mask), ret);
 982	return ret;
 983}
 984
 985int __ceph_caps_used(struct ceph_inode_info *ci)
 986{
 987	int used = 0;
 988	if (ci->i_pin_ref)
 989		used |= CEPH_CAP_PIN;
 990	if (ci->i_rd_ref)
 991		used |= CEPH_CAP_FILE_RD;
 992	if (ci->i_rdcache_ref ||
 993	    (S_ISREG(ci->vfs_inode.i_mode) &&
 994	     ci->vfs_inode.i_data.nrpages))
 995		used |= CEPH_CAP_FILE_CACHE;
 996	if (ci->i_wr_ref)
 997		used |= CEPH_CAP_FILE_WR;
 998	if (ci->i_wb_ref || ci->i_wrbuffer_ref)
 999		used |= CEPH_CAP_FILE_BUFFER;
1000	if (ci->i_fx_ref)
1001		used |= CEPH_CAP_FILE_EXCL;
1002	return used;
1003}
1004
1005#define FMODE_WAIT_BIAS 1000
1006
1007/*
1008 * wanted, by virtue of open file modes
1009 */
1010int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
1011{
1012	const int PIN_SHIFT = ffs(CEPH_FILE_MODE_PIN);
1013	const int RD_SHIFT = ffs(CEPH_FILE_MODE_RD);
1014	const int WR_SHIFT = ffs(CEPH_FILE_MODE_WR);
1015	const int LAZY_SHIFT = ffs(CEPH_FILE_MODE_LAZY);
1016	struct ceph_mount_options *opt =
1017		ceph_inode_to_client(&ci->vfs_inode)->mount_options;
1018	unsigned long used_cutoff = jiffies - opt->caps_wanted_delay_max * HZ;
1019	unsigned long idle_cutoff = jiffies - opt->caps_wanted_delay_min * HZ;
1020
1021	if (S_ISDIR(ci->vfs_inode.i_mode)) {
1022		int want = 0;
1023
1024		/* use used_cutoff here, to keep dir's wanted caps longer */
1025		if (ci->i_nr_by_mode[RD_SHIFT] > 0 ||
1026		    time_after(ci->i_last_rd, used_cutoff))
1027			want |= CEPH_CAP_ANY_SHARED;
1028
1029		if (ci->i_nr_by_mode[WR_SHIFT] > 0 ||
1030		    time_after(ci->i_last_wr, used_cutoff)) {
1031			want |= CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
1032			if (opt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1033				want |= CEPH_CAP_ANY_DIR_OPS;
1034		}
1035
1036		if (want || ci->i_nr_by_mode[PIN_SHIFT] > 0)
1037			want |= CEPH_CAP_PIN;
1038
1039		return want;
1040	} else {
1041		int bits = 0;
1042
1043		if (ci->i_nr_by_mode[RD_SHIFT] > 0) {
1044			if (ci->i_nr_by_mode[RD_SHIFT] >= FMODE_WAIT_BIAS ||
1045			    time_after(ci->i_last_rd, used_cutoff))
1046				bits |= 1 << RD_SHIFT;
1047		} else if (time_after(ci->i_last_rd, idle_cutoff)) {
1048			bits |= 1 << RD_SHIFT;
1049		}
1050
1051		if (ci->i_nr_by_mode[WR_SHIFT] > 0) {
1052			if (ci->i_nr_by_mode[WR_SHIFT] >= FMODE_WAIT_BIAS ||
1053			    time_after(ci->i_last_wr, used_cutoff))
1054				bits |= 1 << WR_SHIFT;
1055		} else if (time_after(ci->i_last_wr, idle_cutoff)) {
1056			bits |= 1 << WR_SHIFT;
1057		}
1058
1059		/* check lazyio only when read/write is wanted */
1060		if ((bits & (CEPH_FILE_MODE_RDWR << 1)) &&
1061		    ci->i_nr_by_mode[LAZY_SHIFT] > 0)
1062			bits |= 1 << LAZY_SHIFT;
1063
1064		return bits ? ceph_caps_for_mode(bits >> 1) : 0;
1065	}
1066}
1067
1068/*
1069 * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
1070 */
1071int __ceph_caps_wanted(struct ceph_inode_info *ci)
1072{
1073	int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
1074	if (S_ISDIR(ci->vfs_inode.i_mode)) {
1075		/* we want EXCL if holding caps of dir ops */
1076		if (w & CEPH_CAP_ANY_DIR_OPS)
1077			w |= CEPH_CAP_FILE_EXCL;
1078	} else {
1079		/* we want EXCL if dirty data */
1080		if (w & CEPH_CAP_FILE_BUFFER)
1081			w |= CEPH_CAP_FILE_EXCL;
1082	}
1083	return w;
1084}
1085
1086/*
1087 * Return caps we have registered with the MDS(s) as 'wanted'.
1088 */
1089int __ceph_caps_mds_wanted(struct ceph_inode_info *ci, bool check)
1090{
1091	struct ceph_cap *cap;
1092	struct rb_node *p;
1093	int mds_wanted = 0;
1094
1095	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1096		cap = rb_entry(p, struct ceph_cap, ci_node);
1097		if (check && !__cap_is_valid(cap))
1098			continue;
1099		if (cap == ci->i_auth_cap)
1100			mds_wanted |= cap->mds_wanted;
1101		else
1102			mds_wanted |= (cap->mds_wanted & ~CEPH_CAP_ANY_FILE_WR);
1103	}
1104	return mds_wanted;
1105}
1106
1107int ceph_is_any_caps(struct inode *inode)
1108{
1109	struct ceph_inode_info *ci = ceph_inode(inode);
1110	int ret;
1111
1112	spin_lock(&ci->i_ceph_lock);
1113	ret = __ceph_is_any_real_caps(ci);
1114	spin_unlock(&ci->i_ceph_lock);
1115
1116	return ret;
1117}
1118
1119static void drop_inode_snap_realm(struct ceph_inode_info *ci)
1120{
1121	struct ceph_snap_realm *realm = ci->i_snap_realm;
1122	spin_lock(&realm->inodes_with_caps_lock);
1123	list_del_init(&ci->i_snap_realm_item);
1124	ci->i_snap_realm_counter++;
1125	ci->i_snap_realm = NULL;
1126	if (realm->ino == ci->i_vino.ino)
1127		realm->inode = NULL;
1128	spin_unlock(&realm->inodes_with_caps_lock);
1129	ceph_put_snap_realm(ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc,
1130			    realm);
1131}
1132
1133/*
1134 * Remove a cap.  Take steps to deal with a racing iterate_session_caps.
1135 *
1136 * caller should hold i_ceph_lock.
1137 * caller will not hold session s_mutex if called from destroy_inode.
1138 */
1139void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
1140{
1141	struct ceph_mds_session *session = cap->session;
1142	struct ceph_inode_info *ci = cap->ci;
1143	struct ceph_mds_client *mdsc =
1144		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1145	int removed = 0;
1146
1147	dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
1148
1149	/* remove from inode's cap rbtree, and clear auth cap */
1150	rb_erase(&cap->ci_node, &ci->i_caps);
1151	if (ci->i_auth_cap == cap) {
1152		WARN_ON_ONCE(!list_empty(&ci->i_dirty_item));
1153		ci->i_auth_cap = NULL;
1154	}
1155
1156	/* remove from session list */
1157	spin_lock(&session->s_cap_lock);
1158	if (session->s_cap_iterator == cap) {
1159		/* not yet, we are iterating over this very cap */
1160		dout("__ceph_remove_cap  delaying %p removal from session %p\n",
1161		     cap, cap->session);
1162	} else {
1163		list_del_init(&cap->session_caps);
1164		session->s_nr_caps--;
1165		atomic64_dec(&mdsc->metric.total_caps);
1166		cap->session = NULL;
1167		removed = 1;
1168	}
1169	/* protect backpointer with s_cap_lock: see iterate_session_caps */
1170	cap->ci = NULL;
 
1171
1172	/*
1173	 * s_cap_reconnect is protected by s_cap_lock. no one changes
1174	 * s_cap_gen while session is in the reconnect state.
1175	 */
1176	if (queue_release &&
1177	    (!session->s_cap_reconnect || cap->cap_gen == session->s_cap_gen)) {
1178		cap->queue_release = 1;
1179		if (removed) {
1180			__ceph_queue_cap_release(session, cap);
1181			removed = 0;
1182		}
1183	} else {
1184		cap->queue_release = 0;
1185	}
1186	cap->cap_ino = ci->i_vino.ino;
1187
1188	spin_unlock(&session->s_cap_lock);
1189
1190	if (removed)
1191		ceph_put_cap(mdsc, cap);
1192
1193	if (!__ceph_is_any_real_caps(ci)) {
1194		/* when reconnect denied, we remove session caps forcibly,
1195		 * i_wr_ref can be non-zero. If there are ongoing write,
1196		 * keep i_snap_realm.
1197		 */
1198		if (ci->i_wr_ref == 0 && ci->i_snap_realm)
1199			drop_inode_snap_realm(ci);
1200
 
 
1201		__cap_delay_cancel(mdsc, ci);
1202	}
1203}
1204
1205struct cap_msg_args {
1206	struct ceph_mds_session	*session;
1207	u64			ino, cid, follows;
1208	u64			flush_tid, oldest_flush_tid, size, max_size;
1209	u64			xattr_version;
1210	u64			change_attr;
1211	struct ceph_buffer	*xattr_buf;
1212	struct ceph_buffer	*old_xattr_buf;
1213	struct timespec64	atime, mtime, ctime, btime;
1214	int			op, caps, wanted, dirty;
1215	u32			seq, issue_seq, mseq, time_warp_seq;
1216	u32			flags;
1217	kuid_t			uid;
1218	kgid_t			gid;
1219	umode_t			mode;
1220	bool			inline_data;
1221	bool			wake;
1222};
1223
1224/*
1225 * Build and send a cap message to the given MDS.
1226 *
1227 * Caller should be holding s_mutex.
1228 */
1229static int send_cap_msg(struct cap_msg_args *arg)
 
 
 
 
 
 
 
 
 
 
1230{
1231	struct ceph_mds_caps *fc;
1232	struct ceph_msg *msg;
1233	void *p;
1234	size_t extra_len;
1235	struct ceph_osd_client *osdc = &arg->session->s_mdsc->fsc->client->osdc;
1236
1237	dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
1238	     " seq %u/%u tid %llu/%llu mseq %u follows %lld size %llu/%llu"
1239	     " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(arg->op),
1240	     arg->cid, arg->ino, ceph_cap_string(arg->caps),
1241	     ceph_cap_string(arg->wanted), ceph_cap_string(arg->dirty),
1242	     arg->seq, arg->issue_seq, arg->flush_tid, arg->oldest_flush_tid,
1243	     arg->mseq, arg->follows, arg->size, arg->max_size,
1244	     arg->xattr_version,
1245	     arg->xattr_buf ? (int)arg->xattr_buf->vec.iov_len : 0);
1246
1247	/* flock buffer size + inline version + inline data size +
1248	 * osd_epoch_barrier + oldest_flush_tid */
1249	extra_len = 4 + 8 + 4 + 4 + 8 + 4 + 4 + 4 + 8 + 8 + 4;
1250	msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc) + extra_len,
1251			   GFP_NOFS, false);
1252	if (!msg)
1253		return -ENOMEM;
1254
1255	msg->hdr.version = cpu_to_le16(10);
1256	msg->hdr.tid = cpu_to_le64(arg->flush_tid);
1257
1258	fc = msg->front.iov_base;
1259	memset(fc, 0, sizeof(*fc));
1260
1261	fc->cap_id = cpu_to_le64(arg->cid);
1262	fc->op = cpu_to_le32(arg->op);
1263	fc->seq = cpu_to_le32(arg->seq);
1264	fc->issue_seq = cpu_to_le32(arg->issue_seq);
1265	fc->migrate_seq = cpu_to_le32(arg->mseq);
1266	fc->caps = cpu_to_le32(arg->caps);
1267	fc->wanted = cpu_to_le32(arg->wanted);
1268	fc->dirty = cpu_to_le32(arg->dirty);
1269	fc->ino = cpu_to_le64(arg->ino);
1270	fc->snap_follows = cpu_to_le64(arg->follows);
1271
1272	fc->size = cpu_to_le64(arg->size);
1273	fc->max_size = cpu_to_le64(arg->max_size);
1274	ceph_encode_timespec64(&fc->mtime, &arg->mtime);
1275	ceph_encode_timespec64(&fc->atime, &arg->atime);
1276	ceph_encode_timespec64(&fc->ctime, &arg->ctime);
1277	fc->time_warp_seq = cpu_to_le32(arg->time_warp_seq);
1278
1279	fc->uid = cpu_to_le32(from_kuid(&init_user_ns, arg->uid));
1280	fc->gid = cpu_to_le32(from_kgid(&init_user_ns, arg->gid));
1281	fc->mode = cpu_to_le32(arg->mode);
1282
1283	fc->xattr_version = cpu_to_le64(arg->xattr_version);
1284	if (arg->xattr_buf) {
1285		msg->middle = ceph_buffer_get(arg->xattr_buf);
1286		fc->xattr_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1287		msg->hdr.middle_len = cpu_to_le32(arg->xattr_buf->vec.iov_len);
1288	}
1289
1290	p = fc + 1;
1291	/* flock buffer size (version 2) */
1292	ceph_encode_32(&p, 0);
1293	/* inline version (version 4) */
1294	ceph_encode_64(&p, arg->inline_data ? 0 : CEPH_INLINE_NONE);
1295	/* inline data size */
1296	ceph_encode_32(&p, 0);
1297	/*
1298	 * osd_epoch_barrier (version 5)
1299	 * The epoch_barrier is protected osdc->lock, so READ_ONCE here in
1300	 * case it was recently changed
1301	 */
1302	ceph_encode_32(&p, READ_ONCE(osdc->epoch_barrier));
1303	/* oldest_flush_tid (version 6) */
1304	ceph_encode_64(&p, arg->oldest_flush_tid);
1305
1306	/*
1307	 * caller_uid/caller_gid (version 7)
1308	 *
1309	 * Currently, we don't properly track which caller dirtied the caps
1310	 * last, and force a flush of them when there is a conflict. For now,
1311	 * just set this to 0:0, to emulate how the MDS has worked up to now.
1312	 */
1313	ceph_encode_32(&p, 0);
1314	ceph_encode_32(&p, 0);
1315
1316	/* pool namespace (version 8) (mds always ignores this) */
1317	ceph_encode_32(&p, 0);
 
 
 
 
 
1318
1319	/* btime and change_attr (version 9) */
1320	ceph_encode_timespec64(p, &arg->btime);
1321	p += sizeof(struct ceph_timespec);
1322	ceph_encode_64(&p, arg->change_attr);
1323
1324	/* Advisory flags (version 10) */
1325	ceph_encode_32(&p, arg->flags);
1326
1327	ceph_con_send(&arg->session->s_con, msg);
1328	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1329}
1330
1331/*
1332 * Queue cap releases when an inode is dropped from our cache.
 
1333 */
1334void __ceph_remove_caps(struct ceph_inode_info *ci)
1335{
 
1336	struct rb_node *p;
1337
1338	/* lock i_ceph_lock, because ceph_d_revalidate(..., LOOKUP_RCU)
1339	 * may call __ceph_caps_issued_mask() on a freeing inode. */
1340	spin_lock(&ci->i_ceph_lock);
1341	p = rb_first(&ci->i_caps);
1342	while (p) {
1343		struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
 
 
 
 
1344		p = rb_next(p);
1345		__ceph_remove_cap(cap, true);
1346	}
1347	spin_unlock(&ci->i_ceph_lock);
1348}
1349
1350/*
1351 * Prepare to send a cap message to an MDS. Update the cap state, and populate
1352 * the arg struct with the parameters that will need to be sent. This should
1353 * be done under the i_ceph_lock to guard against changes to cap state.
1354 *
1355 * Make note of max_size reported/requested from mds, revoked caps
1356 * that have now been implemented.
1357 */
1358static void __prep_cap(struct cap_msg_args *arg, struct ceph_cap *cap,
1359		       int op, int flags, int used, int want, int retain,
1360		       int flushing, u64 flush_tid, u64 oldest_flush_tid)
 
 
 
 
 
 
 
 
 
 
 
1361{
1362	struct ceph_inode_info *ci = cap->ci;
1363	struct inode *inode = &ci->vfs_inode;
1364	int held, revoking;
1365
1366	lockdep_assert_held(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
1367
1368	held = cap->issued | cap->implemented;
1369	revoking = cap->implemented & ~cap->issued;
1370	retain &= ~revoking;
 
1371
1372	dout("%s %p cap %p session %p %s -> %s (revoking %s)\n",
1373	     __func__, inode, cap, cap->session,
1374	     ceph_cap_string(held), ceph_cap_string(held & retain),
1375	     ceph_cap_string(revoking));
1376	BUG_ON((retain & CEPH_CAP_PIN) == 0);
1377
1378	ci->i_ceph_flags &= ~CEPH_I_FLUSH;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1379
1380	cap->issued &= retain;  /* drop bits we don't want */
1381	/*
1382	 * Wake up any waiters on wanted -> needed transition. This is due to
1383	 * the weird transition from buffered to sync IO... we need to flush
1384	 * dirty pages _before_ allowing sync writes to avoid reordering.
1385	 */
1386	arg->wake = cap->implemented & ~cap->issued;
 
 
 
1387	cap->implemented &= cap->issued | used;
1388	cap->mds_wanted = want;
1389
1390	arg->session = cap->session;
1391	arg->ino = ceph_vino(inode).ino;
1392	arg->cid = cap->cap_id;
1393	arg->follows = flushing ? ci->i_head_snapc->seq : 0;
1394	arg->flush_tid = flush_tid;
1395	arg->oldest_flush_tid = oldest_flush_tid;
1396
1397	arg->size = inode->i_size;
1398	ci->i_reported_size = arg->size;
1399	arg->max_size = ci->i_wanted_max_size;
1400	if (cap == ci->i_auth_cap) {
1401		if (want & CEPH_CAP_ANY_FILE_WR)
1402			ci->i_requested_max_size = arg->max_size;
1403		else
1404			ci->i_requested_max_size = 0;
1405	}
1406
1407	if (flushing & CEPH_CAP_XATTR_EXCL) {
1408		arg->old_xattr_buf = __ceph_build_xattrs_blob(ci);
1409		arg->xattr_version = ci->i_xattrs.version;
1410		arg->xattr_buf = ci->i_xattrs.blob;
1411	} else {
1412		arg->xattr_buf = NULL;
1413		arg->old_xattr_buf = NULL;
1414	}
1415
1416	arg->mtime = inode->i_mtime;
1417	arg->atime = inode->i_atime;
1418	arg->ctime = inode->i_ctime;
1419	arg->btime = ci->i_btime;
1420	arg->change_attr = inode_peek_iversion_raw(inode);
1421
1422	arg->op = op;
1423	arg->caps = cap->implemented;
1424	arg->wanted = want;
1425	arg->dirty = flushing;
1426
1427	arg->seq = cap->seq;
1428	arg->issue_seq = cap->issue_seq;
1429	arg->mseq = cap->mseq;
1430	arg->time_warp_seq = ci->i_time_warp_seq;
1431
1432	arg->uid = inode->i_uid;
1433	arg->gid = inode->i_gid;
1434	arg->mode = inode->i_mode;
1435
1436	arg->inline_data = ci->i_inline_version != CEPH_INLINE_NONE;
1437	if (!(flags & CEPH_CLIENT_CAPS_PENDING_CAPSNAP) &&
1438	    !list_empty(&ci->i_cap_snaps)) {
1439		struct ceph_cap_snap *capsnap;
1440		list_for_each_entry_reverse(capsnap, &ci->i_cap_snaps, ci_item) {
1441			if (capsnap->cap_flush.tid)
1442				break;
1443			if (capsnap->need_flush) {
1444				flags |= CEPH_CLIENT_CAPS_PENDING_CAPSNAP;
1445				break;
1446			}
1447		}
1448	}
1449	arg->flags = flags;
1450}
1451
1452/*
1453 * Send a cap msg on the given inode.
1454 *
1455 * Caller should hold snap_rwsem (read), s_mutex.
1456 */
1457static void __send_cap(struct ceph_mds_client *mdsc, struct cap_msg_args *arg,
1458		       struct ceph_inode_info *ci)
1459{
1460	struct inode *inode = &ci->vfs_inode;
1461	int ret;
1462
1463	ret = send_cap_msg(arg);
 
 
 
 
1464	if (ret < 0) {
1465		pr_err("error sending cap msg, ino (%llx.%llx) "
1466		       "flushing %s tid %llu, requeue\n",
1467		       ceph_vinop(inode), ceph_cap_string(arg->dirty),
1468		       arg->flush_tid);
1469		spin_lock(&ci->i_ceph_lock);
1470		__cap_delay_requeue(mdsc, ci);
1471		spin_unlock(&ci->i_ceph_lock);
1472	}
1473
1474	ceph_buffer_put(arg->old_xattr_buf);
1475
1476	if (arg->wake)
1477		wake_up_all(&ci->i_cap_wq);
1478}
1479
1480static inline int __send_flush_snap(struct inode *inode,
1481				    struct ceph_mds_session *session,
1482				    struct ceph_cap_snap *capsnap,
1483				    u32 mseq, u64 oldest_flush_tid)
1484{
1485	struct cap_msg_args	arg;
1486
1487	arg.session = session;
1488	arg.ino = ceph_vino(inode).ino;
1489	arg.cid = 0;
1490	arg.follows = capsnap->follows;
1491	arg.flush_tid = capsnap->cap_flush.tid;
1492	arg.oldest_flush_tid = oldest_flush_tid;
1493
1494	arg.size = capsnap->size;
1495	arg.max_size = 0;
1496	arg.xattr_version = capsnap->xattr_version;
1497	arg.xattr_buf = capsnap->xattr_blob;
1498	arg.old_xattr_buf = NULL;
1499
1500	arg.atime = capsnap->atime;
1501	arg.mtime = capsnap->mtime;
1502	arg.ctime = capsnap->ctime;
1503	arg.btime = capsnap->btime;
1504	arg.change_attr = capsnap->change_attr;
1505
1506	arg.op = CEPH_CAP_OP_FLUSHSNAP;
1507	arg.caps = capsnap->issued;
1508	arg.wanted = 0;
1509	arg.dirty = capsnap->dirty;
1510
1511	arg.seq = 0;
1512	arg.issue_seq = 0;
1513	arg.mseq = mseq;
1514	arg.time_warp_seq = capsnap->time_warp_seq;
1515
1516	arg.uid = capsnap->uid;
1517	arg.gid = capsnap->gid;
1518	arg.mode = capsnap->mode;
1519
1520	arg.inline_data = capsnap->inline_data;
1521	arg.flags = 0;
1522	arg.wake = false;
1523
1524	return send_cap_msg(&arg);
1525}
1526
1527/*
1528 * When a snapshot is taken, clients accumulate dirty metadata on
1529 * inodes with capabilities in ceph_cap_snaps to describe the file
1530 * state at the time the snapshot was taken.  This must be flushed
1531 * asynchronously back to the MDS once sync writes complete and dirty
1532 * data is written out.
1533 *
 
 
 
1534 * Called under i_ceph_lock.  Takes s_mutex as needed.
1535 */
1536static void __ceph_flush_snaps(struct ceph_inode_info *ci,
1537			       struct ceph_mds_session *session)
 
1538		__releases(ci->i_ceph_lock)
1539		__acquires(ci->i_ceph_lock)
1540{
1541	struct inode *inode = &ci->vfs_inode;
1542	struct ceph_mds_client *mdsc = session->s_mdsc;
1543	struct ceph_cap_snap *capsnap;
1544	u64 oldest_flush_tid = 0;
1545	u64 first_tid = 1, last_tid = 0;
 
 
 
 
 
1546
1547	dout("__flush_snaps %p session %p\n", inode, session);
 
1548
 
 
1549	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
 
 
 
1550		/*
1551		 * we need to wait for sync writes to complete and for dirty
1552		 * pages to be written out.
1553		 */
1554		if (capsnap->dirty_pages || capsnap->writing)
1555			break;
1556
1557		/* should be removed by ceph_try_drop_cap_snap() */
1558		BUG_ON(!capsnap->need_flush);
 
 
 
 
 
 
 
 
 
1559
1560		/* only flush each capsnap once */
1561		if (capsnap->cap_flush.tid > 0) {
1562			dout(" already flushed %p, skipping\n", capsnap);
1563			continue;
1564		}
1565
1566		spin_lock(&mdsc->cap_dirty_lock);
1567		capsnap->cap_flush.tid = ++mdsc->last_cap_flush_tid;
1568		list_add_tail(&capsnap->cap_flush.g_list,
1569			      &mdsc->cap_flush_list);
1570		if (oldest_flush_tid == 0)
1571			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1572		if (list_empty(&ci->i_flushing_item)) {
1573			list_add_tail(&ci->i_flushing_item,
1574				      &session->s_cap_flushing);
1575		}
1576		spin_unlock(&mdsc->cap_dirty_lock);
1577
1578		list_add_tail(&capsnap->cap_flush.i_list,
1579			      &ci->i_cap_flush_list);
1580
1581		if (first_tid == 1)
1582			first_tid = capsnap->cap_flush.tid;
1583		last_tid = capsnap->cap_flush.tid;
1584	}
1585
1586	ci->i_ceph_flags &= ~CEPH_I_FLUSH_SNAPS;
1587
1588	while (first_tid <= last_tid) {
1589		struct ceph_cap *cap = ci->i_auth_cap;
1590		struct ceph_cap_flush *cf;
1591		int ret;
1592
1593		if (!(cap && cap->session == session)) {
1594			dout("__flush_snaps %p auth cap %p not mds%d, "
1595			     "stop\n", inode, cap, session->s_mds);
1596			break;
1597		}
1598
1599		ret = -ENOENT;
1600		list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
1601			if (cf->tid >= first_tid) {
1602				ret = 0;
1603				break;
 
 
 
1604			}
 
 
 
 
 
 
 
1605		}
1606		if (ret < 0)
1607			break;
1608
1609		first_tid = cf->tid + 1;
1610
1611		capsnap = container_of(cf, struct ceph_cap_snap, cap_flush);
1612		refcount_inc(&capsnap->nref);
 
 
1613		spin_unlock(&ci->i_ceph_lock);
1614
1615		dout("__flush_snaps %p capsnap %p tid %llu %s\n",
1616		     inode, capsnap, cf->tid, ceph_cap_string(capsnap->dirty));
 
 
 
 
 
 
 
 
 
1617
1618		ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
1619					oldest_flush_tid);
1620		if (ret < 0) {
1621			pr_err("__flush_snaps: error sending cap flushsnap, "
1622			       "ino (%llx.%llx) tid %llu follows %llu\n",
1623				ceph_vinop(inode), cf->tid, capsnap->follows);
1624		}
1625
1626		ceph_put_cap_snap(capsnap);
1627		spin_lock(&ci->i_ceph_lock);
 
1628	}
1629}
1630
1631void ceph_flush_snaps(struct ceph_inode_info *ci,
1632		      struct ceph_mds_session **psession)
1633{
1634	struct inode *inode = &ci->vfs_inode;
1635	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1636	struct ceph_mds_session *session = NULL;
1637	int mds;
1638
1639	dout("ceph_flush_snaps %p\n", inode);
1640	if (psession)
1641		session = *psession;
1642retry:
1643	spin_lock(&ci->i_ceph_lock);
1644	if (!(ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)) {
1645		dout(" no capsnap needs flush, doing nothing\n");
1646		goto out;
1647	}
1648	if (!ci->i_auth_cap) {
1649		dout(" no auth cap (migrating?), doing nothing\n");
1650		goto out;
1651	}
1652
1653	mds = ci->i_auth_cap->session->s_mds;
1654	if (session && session->s_mds != mds) {
1655		dout(" oops, wrong session %p mutex\n", session);
1656		mutex_unlock(&session->s_mutex);
1657		ceph_put_mds_session(session);
1658		session = NULL;
1659	}
1660	if (!session) {
1661		spin_unlock(&ci->i_ceph_lock);
1662		mutex_lock(&mdsc->mutex);
1663		session = __ceph_lookup_mds_session(mdsc, mds);
1664		mutex_unlock(&mdsc->mutex);
1665		if (session) {
1666			dout(" inverting session/ino locks on %p\n", session);
1667			mutex_lock(&session->s_mutex);
1668		}
1669		goto retry;
1670	}
 
1671
1672	// make sure flushsnap messages are sent in proper order.
1673	if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
1674		__kick_flushing_caps(mdsc, session, ci, 0);
1675
1676	__ceph_flush_snaps(ci, session);
1677out:
1678	spin_unlock(&ci->i_ceph_lock);
1679
1680	if (psession) {
1681		*psession = session;
1682	} else if (session) {
1683		mutex_unlock(&session->s_mutex);
1684		ceph_put_mds_session(session);
1685	}
1686	/* we flushed them all; remove this inode from the queue */
1687	spin_lock(&mdsc->snap_flush_lock);
1688	list_del_init(&ci->i_snap_flush_item);
1689	spin_unlock(&mdsc->snap_flush_lock);
1690}
1691
1692/*
1693 * Mark caps dirty.  If inode is newly dirty, return the dirty flags.
1694 * Caller is then responsible for calling __mark_inode_dirty with the
1695 * returned flags value.
1696 */
1697int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask,
1698			   struct ceph_cap_flush **pcf)
1699{
1700	struct ceph_mds_client *mdsc =
1701		ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
1702	struct inode *inode = &ci->vfs_inode;
1703	int was = ci->i_dirty_caps;
1704	int dirty = 0;
1705
1706	lockdep_assert_held(&ci->i_ceph_lock);
1707
1708	if (!ci->i_auth_cap) {
1709		pr_warn("__mark_dirty_caps %p %llx mask %s, "
1710			"but no auth cap (session was closed?)\n",
1711			inode, ceph_ino(inode), ceph_cap_string(mask));
1712		return 0;
1713	}
1714
1715	dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1716	     ceph_cap_string(mask), ceph_cap_string(was),
1717	     ceph_cap_string(was | mask));
1718	ci->i_dirty_caps |= mask;
1719	if (was == 0) {
1720		struct ceph_mds_session *session = ci->i_auth_cap->session;
1721
1722		WARN_ON_ONCE(ci->i_prealloc_cap_flush);
1723		swap(ci->i_prealloc_cap_flush, *pcf);
1724
1725		if (!ci->i_head_snapc) {
1726			WARN_ON_ONCE(!rwsem_is_locked(&mdsc->snap_rwsem));
1727			ci->i_head_snapc = ceph_get_snap_context(
1728				ci->i_snap_realm->cached_context);
1729		}
1730		dout(" inode %p now dirty snapc %p auth cap %p\n",
1731		     &ci->vfs_inode, ci->i_head_snapc, ci->i_auth_cap);
1732		BUG_ON(!list_empty(&ci->i_dirty_item));
1733		spin_lock(&mdsc->cap_dirty_lock);
1734		list_add(&ci->i_dirty_item, &session->s_cap_dirty);
1735		spin_unlock(&mdsc->cap_dirty_lock);
1736		if (ci->i_flushing_caps == 0) {
1737			ihold(inode);
1738			dirty |= I_DIRTY_SYNC;
1739		}
1740	} else {
1741		WARN_ON_ONCE(!ci->i_prealloc_cap_flush);
1742	}
1743	BUG_ON(list_empty(&ci->i_dirty_item));
1744	if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1745	    (mask & CEPH_CAP_FILE_BUFFER))
1746		dirty |= I_DIRTY_DATASYNC;
1747	__cap_delay_requeue(mdsc, ci);
1748	return dirty;
1749}
1750
1751struct ceph_cap_flush *ceph_alloc_cap_flush(void)
1752{
1753	return kmem_cache_alloc(ceph_cap_flush_cachep, GFP_KERNEL);
1754}
1755
1756void ceph_free_cap_flush(struct ceph_cap_flush *cf)
1757{
1758	if (cf)
1759		kmem_cache_free(ceph_cap_flush_cachep, cf);
1760}
1761
1762static u64 __get_oldest_flush_tid(struct ceph_mds_client *mdsc)
1763{
1764	if (!list_empty(&mdsc->cap_flush_list)) {
1765		struct ceph_cap_flush *cf =
1766			list_first_entry(&mdsc->cap_flush_list,
1767					 struct ceph_cap_flush, g_list);
1768		return cf->tid;
1769	}
1770	return 0;
1771}
1772
1773/*
1774 * Remove cap_flush from the mdsc's or inode's flushing cap list.
1775 * Return true if caller needs to wake up flush waiters.
1776 */
1777static bool __detach_cap_flush_from_mdsc(struct ceph_mds_client *mdsc,
1778					 struct ceph_cap_flush *cf)
1779{
1780	struct ceph_cap_flush *prev;
1781	bool wake = cf->wake;
1782
1783	if (wake && cf->g_list.prev != &mdsc->cap_flush_list) {
1784		prev = list_prev_entry(cf, g_list);
1785		prev->wake = true;
1786		wake = false;
1787	}
1788	list_del(&cf->g_list);
1789	return wake;
1790}
1791
1792static bool __detach_cap_flush_from_ci(struct ceph_inode_info *ci,
1793				       struct ceph_cap_flush *cf)
1794{
1795	struct ceph_cap_flush *prev;
1796	bool wake = cf->wake;
1797
1798	if (wake && cf->i_list.prev != &ci->i_cap_flush_list) {
1799		prev = list_prev_entry(cf, i_list);
1800		prev->wake = true;
1801		wake = false;
1802	}
1803	list_del(&cf->i_list);
1804	return wake;
1805}
1806
1807/*
1808 * Add dirty inode to the flushing list.  Assigned a seq number so we
1809 * can wait for caps to flush without starving.
1810 *
1811 * Called under i_ceph_lock. Returns the flush tid.
1812 */
1813static u64 __mark_caps_flushing(struct inode *inode,
1814				struct ceph_mds_session *session, bool wake,
1815				u64 *oldest_flush_tid)
1816{
1817	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1818	struct ceph_inode_info *ci = ceph_inode(inode);
1819	struct ceph_cap_flush *cf = NULL;
1820	int flushing;
1821
1822	lockdep_assert_held(&ci->i_ceph_lock);
1823	BUG_ON(ci->i_dirty_caps == 0);
1824	BUG_ON(list_empty(&ci->i_dirty_item));
1825	BUG_ON(!ci->i_prealloc_cap_flush);
1826
1827	flushing = ci->i_dirty_caps;
1828	dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1829	     ceph_cap_string(flushing),
1830	     ceph_cap_string(ci->i_flushing_caps),
1831	     ceph_cap_string(ci->i_flushing_caps | flushing));
1832	ci->i_flushing_caps |= flushing;
1833	ci->i_dirty_caps = 0;
1834	dout(" inode %p now !dirty\n", inode);
1835
1836	swap(cf, ci->i_prealloc_cap_flush);
1837	cf->caps = flushing;
1838	cf->wake = wake;
1839
1840	spin_lock(&mdsc->cap_dirty_lock);
1841	list_del_init(&ci->i_dirty_item);
1842
1843	cf->tid = ++mdsc->last_cap_flush_tid;
1844	list_add_tail(&cf->g_list, &mdsc->cap_flush_list);
1845	*oldest_flush_tid = __get_oldest_flush_tid(mdsc);
1846
1847	if (list_empty(&ci->i_flushing_item)) {
1848		list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1849		mdsc->num_cap_flushing++;
 
 
 
 
 
 
1850	}
1851	spin_unlock(&mdsc->cap_dirty_lock);
1852
1853	list_add_tail(&cf->i_list, &ci->i_cap_flush_list);
1854
1855	return cf->tid;
1856}
1857
1858/*
1859 * try to invalidate mapping pages without blocking.
1860 */
1861static int try_nonblocking_invalidate(struct inode *inode)
1862{
1863	struct ceph_inode_info *ci = ceph_inode(inode);
1864	u32 invalidating_gen = ci->i_rdcache_gen;
1865
1866	spin_unlock(&ci->i_ceph_lock);
1867	invalidate_mapping_pages(&inode->i_data, 0, -1);
1868	spin_lock(&ci->i_ceph_lock);
1869
1870	if (inode->i_data.nrpages == 0 &&
1871	    invalidating_gen == ci->i_rdcache_gen) {
1872		/* success. */
1873		dout("try_nonblocking_invalidate %p success\n", inode);
1874		/* save any racing async invalidate some trouble */
1875		ci->i_rdcache_revoking = ci->i_rdcache_gen - 1;
1876		return 0;
1877	}
1878	dout("try_nonblocking_invalidate %p failed\n", inode);
1879	return -1;
1880}
1881
1882bool __ceph_should_report_size(struct ceph_inode_info *ci)
1883{
1884	loff_t size = ci->vfs_inode.i_size;
1885	/* mds will adjust max size according to the reported size */
1886	if (ci->i_flushing_caps & CEPH_CAP_FILE_WR)
1887		return false;
1888	if (size >= ci->i_max_size)
1889		return true;
1890	/* half of previous max_size increment has been used */
1891	if (ci->i_max_size > ci->i_reported_size &&
1892	    (size << 1) >= ci->i_max_size + ci->i_reported_size)
1893		return true;
1894	return false;
1895}
1896
1897/*
1898 * Swiss army knife function to examine currently used and wanted
1899 * versus held caps.  Release, flush, ack revoked caps to mds as
1900 * appropriate.
1901 *
 
 
1902 *  CHECK_CAPS_AUTHONLY - we should only check the auth cap
1903 *  CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1904 *    further delay.
1905 */
1906void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1907		     struct ceph_mds_session *session)
1908{
1909	struct ceph_fs_client *fsc = ceph_inode_to_client(&ci->vfs_inode);
1910	struct ceph_mds_client *mdsc = fsc->mdsc;
1911	struct inode *inode = &ci->vfs_inode;
1912	struct ceph_cap *cap;
1913	u64 flush_tid, oldest_flush_tid;
1914	int file_wanted, used, cap_used;
1915	int took_snap_rwsem = 0;             /* true if mdsc->snap_rwsem held */
1916	int issued, implemented, want, retain, revoking, flushing = 0;
1917	int mds = -1;   /* keep track of how far we've gone through i_caps list
1918			   to avoid an infinite loop on retry */
1919	struct rb_node *p;
1920	bool queue_invalidate = false;
1921	bool tried_invalidate = false;
 
 
 
 
 
 
1922
1923	spin_lock(&ci->i_ceph_lock);
 
1924	if (ci->i_ceph_flags & CEPH_I_FLUSH)
1925		flags |= CHECK_CAPS_FLUSH;
1926
 
 
 
1927	goto retry_locked;
1928retry:
1929	spin_lock(&ci->i_ceph_lock);
1930retry_locked:
1931	file_wanted = __ceph_caps_file_wanted(ci);
1932	used = __ceph_caps_used(ci);
 
1933	issued = __ceph_caps_issued(ci, &implemented);
1934	revoking = implemented & ~issued;
1935
1936	want = file_wanted;
1937	retain = file_wanted | used | CEPH_CAP_PIN;
1938	if (!mdsc->stopping && inode->i_nlink > 0) {
1939		if (file_wanted) {
1940			retain |= CEPH_CAP_ANY;       /* be greedy */
1941		} else if (S_ISDIR(inode->i_mode) &&
1942			   (issued & CEPH_CAP_FILE_SHARED) &&
1943			   __ceph_dir_is_complete(ci)) {
1944			/*
1945			 * If a directory is complete, we want to keep
1946			 * the exclusive cap. So that MDS does not end up
1947			 * revoking the shared cap on every create/unlink
1948			 * operation.
1949			 */
1950			if (IS_RDONLY(inode)) {
1951				want = CEPH_CAP_ANY_SHARED;
1952			} else {
1953				want |= CEPH_CAP_ANY_SHARED | CEPH_CAP_FILE_EXCL;
1954			}
1955			retain |= want;
1956		} else {
1957
1958			retain |= CEPH_CAP_ANY_SHARED;
1959			/*
1960			 * keep RD only if we didn't have the file open RW,
1961			 * because then the mds would revoke it anyway to
1962			 * journal max_size=0.
1963			 */
1964			if (ci->i_max_size == 0)
1965				retain |= CEPH_CAP_ANY_RD;
1966		}
1967	}
1968
1969	dout("check_caps %p file_want %s used %s dirty %s flushing %s"
1970	     " issued %s revoking %s retain %s %s%s\n", inode,
1971	     ceph_cap_string(file_wanted),
1972	     ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1973	     ceph_cap_string(ci->i_flushing_caps),
1974	     ceph_cap_string(issued), ceph_cap_string(revoking),
1975	     ceph_cap_string(retain),
1976	     (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
 
1977	     (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1978
1979	/*
1980	 * If we no longer need to hold onto old our caps, and we may
1981	 * have cached pages, but don't want them, then try to invalidate.
1982	 * If we fail, it's because pages are locked.... try again later.
1983	 */
1984	if ((!(flags & CHECK_CAPS_NOINVAL) || mdsc->stopping) &&
1985	    S_ISREG(inode->i_mode) &&
1986	    !(ci->i_wb_ref || ci->i_wrbuffer_ref) &&   /* no dirty pages... */
1987	    inode->i_data.nrpages &&		/* have cached pages */
1988	    (revoking & (CEPH_CAP_FILE_CACHE|
1989			 CEPH_CAP_FILE_LAZYIO)) && /*  or revoking cache */
1990	    !tried_invalidate) {
1991		dout("check_caps trying to invalidate on %p\n", inode);
1992		if (try_nonblocking_invalidate(inode) < 0) {
1993			dout("check_caps queuing invalidate\n");
1994			queue_invalidate = true;
1995			ci->i_rdcache_revoking = ci->i_rdcache_gen;
 
 
 
 
 
 
 
 
 
1996		}
1997		tried_invalidate = true;
1998		goto retry_locked;
1999	}
2000
 
2001	for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
2002		int mflags = 0;
2003		struct cap_msg_args arg;
2004
2005		cap = rb_entry(p, struct ceph_cap, ci_node);
 
2006
2007		/* avoid looping forever */
2008		if (mds >= cap->mds ||
2009		    ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
2010			continue;
2011
2012		/* NOTE: no side-effects allowed, until we take s_mutex */
2013
2014		cap_used = used;
2015		if (ci->i_auth_cap && cap != ci->i_auth_cap)
2016			cap_used &= ~ci->i_auth_cap->issued;
2017
2018		revoking = cap->implemented & ~cap->issued;
2019		dout(" mds%d cap %p used %s issued %s implemented %s revoking %s\n",
2020		     cap->mds, cap, ceph_cap_string(cap_used),
2021		     ceph_cap_string(cap->issued),
2022		     ceph_cap_string(cap->implemented),
2023		     ceph_cap_string(revoking));
2024
2025		if (cap == ci->i_auth_cap &&
2026		    (cap->issued & CEPH_CAP_FILE_WR)) {
2027			/* request larger max_size from MDS? */
2028			if (ci->i_wanted_max_size > ci->i_max_size &&
2029			    ci->i_wanted_max_size > ci->i_requested_max_size) {
2030				dout("requesting new max_size\n");
2031				goto ack;
2032			}
2033
2034			/* approaching file_max? */
2035			if (__ceph_should_report_size(ci)) {
 
2036				dout("i_size approaching max_size\n");
2037				goto ack;
2038			}
2039		}
2040		/* flush anything dirty? */
2041		if (cap == ci->i_auth_cap) {
2042			if ((flags & CHECK_CAPS_FLUSH) && ci->i_dirty_caps) {
2043				dout("flushing dirty caps\n");
2044				goto ack;
2045			}
2046			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS) {
2047				dout("flushing snap caps\n");
2048				goto ack;
2049			}
2050		}
2051
2052		/* completed revocation? going down and there are no caps? */
2053		if (revoking && (revoking & cap_used) == 0) {
2054			dout("completed revocation of %s\n",
2055			     ceph_cap_string(cap->implemented & ~cap->issued));
2056			goto ack;
2057		}
2058
2059		/* want more caps from mds? */
2060		if (want & ~cap->mds_wanted) {
2061			if (want & ~(cap->mds_wanted | cap->issued))
2062				goto ack;
2063			if (!__cap_is_valid(cap))
2064				goto ack;
2065		}
2066
2067		/* things we might delay */
2068		if ((cap->issued & ~retain) == 0)
 
2069			continue;     /* nope, all good */
2070
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2071ack:
 
 
 
 
 
2072		if (session && session != cap->session) {
2073			dout("oops, wrong session %p mutex\n", session);
2074			mutex_unlock(&session->s_mutex);
2075			session = NULL;
2076		}
2077		if (!session) {
2078			session = cap->session;
2079			if (mutex_trylock(&session->s_mutex) == 0) {
2080				dout("inverting session/ino locks on %p\n",
2081				     session);
2082				session = ceph_get_mds_session(session);
2083				spin_unlock(&ci->i_ceph_lock);
2084				if (took_snap_rwsem) {
2085					up_read(&mdsc->snap_rwsem);
2086					took_snap_rwsem = 0;
2087				}
2088				if (session) {
2089					mutex_lock(&session->s_mutex);
2090					ceph_put_mds_session(session);
2091				} else {
2092					/*
2093					 * Because we take the reference while
2094					 * holding the i_ceph_lock, it should
2095					 * never be NULL. Throw a warning if it
2096					 * ever is.
2097					 */
2098					WARN_ON_ONCE(true);
2099				}
2100				goto retry;
2101			}
2102		}
2103
2104		/* kick flushing and flush snaps before sending normal
2105		 * cap message */
2106		if (cap == ci->i_auth_cap &&
2107		    (ci->i_ceph_flags &
2108		     (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS))) {
2109			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2110				__kick_flushing_caps(mdsc, session, ci, 0);
2111			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2112				__ceph_flush_snaps(ci, session);
2113
2114			goto retry_locked;
2115		}
2116
2117		/* take snap_rwsem after session mutex */
2118		if (!took_snap_rwsem) {
2119			if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
2120				dout("inverting snap/in locks on %p\n",
2121				     inode);
2122				spin_unlock(&ci->i_ceph_lock);
2123				down_read(&mdsc->snap_rwsem);
2124				took_snap_rwsem = 1;
2125				goto retry;
2126			}
2127			took_snap_rwsem = 1;
2128		}
2129
2130		if (cap == ci->i_auth_cap && ci->i_dirty_caps) {
2131			flushing = ci->i_dirty_caps;
2132			flush_tid = __mark_caps_flushing(inode, session, false,
2133							 &oldest_flush_tid);
2134			if (flags & CHECK_CAPS_FLUSH &&
2135			    list_empty(&session->s_cap_dirty))
2136				mflags |= CEPH_CLIENT_CAPS_SYNC;
2137		} else {
2138			flushing = 0;
2139			flush_tid = 0;
2140			spin_lock(&mdsc->cap_dirty_lock);
2141			oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2142			spin_unlock(&mdsc->cap_dirty_lock);
2143		}
2144
2145		mds = cap->mds;  /* remember mds, so we don't repeat */
 
2146
2147		__prep_cap(&arg, cap, CEPH_CAP_OP_UPDATE, mflags, cap_used,
2148			   want, retain, flushing, flush_tid, oldest_flush_tid);
2149		spin_unlock(&ci->i_ceph_lock);
2150
2151		__send_cap(mdsc, &arg, ci);
2152
2153		goto retry; /* retake i_ceph_lock and restart our cap scan. */
2154	}
2155
2156	/* periodically re-calculate caps wanted by open files */
2157	if (__ceph_is_any_real_caps(ci) &&
2158	    list_empty(&ci->i_cap_delay_list) &&
2159	    (file_wanted & ~CEPH_CAP_PIN) &&
2160	    !(used & (CEPH_CAP_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
 
 
 
 
2161		__cap_delay_requeue(mdsc, ci);
2162	}
2163
2164	spin_unlock(&ci->i_ceph_lock);
2165
2166	if (queue_invalidate)
2167		ceph_queue_invalidate(inode);
2168
2169	if (session)
2170		mutex_unlock(&session->s_mutex);
2171	if (took_snap_rwsem)
2172		up_read(&mdsc->snap_rwsem);
2173}
2174
2175/*
2176 * Try to flush dirty caps back to the auth mds.
2177 */
2178static int try_flush_caps(struct inode *inode, u64 *ptid)
 
2179{
2180	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
2181	struct ceph_inode_info *ci = ceph_inode(inode);
2182	struct ceph_mds_session *session = NULL;
2183	int flushing = 0;
2184	u64 flush_tid = 0, oldest_flush_tid = 0;
2185
2186retry:
2187	spin_lock(&ci->i_ceph_lock);
2188retry_locked:
 
 
 
2189	if (ci->i_dirty_caps && ci->i_auth_cap) {
2190		struct ceph_cap *cap = ci->i_auth_cap;
2191		struct cap_msg_args arg;
 
 
2192
2193		if (session != cap->session) {
2194			spin_unlock(&ci->i_ceph_lock);
2195			if (session)
2196				mutex_unlock(&session->s_mutex);
2197			session = cap->session;
2198			mutex_lock(&session->s_mutex);
2199			goto retry;
2200		}
2201		if (cap->session->s_state < CEPH_MDS_SESSION_OPEN) {
2202			spin_unlock(&ci->i_ceph_lock);
2203			goto out;
2204		}
2205
2206		if (ci->i_ceph_flags &
2207		    (CEPH_I_KICK_FLUSH | CEPH_I_FLUSH_SNAPS)) {
2208			if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH)
2209				__kick_flushing_caps(mdsc, session, ci, 0);
2210			if (ci->i_ceph_flags & CEPH_I_FLUSH_SNAPS)
2211				__ceph_flush_snaps(ci, session);
2212			goto retry_locked;
2213		}
2214
2215		flushing = ci->i_dirty_caps;
2216		flush_tid = __mark_caps_flushing(inode, session, true,
2217						 &oldest_flush_tid);
2218
2219		__prep_cap(&arg, cap, CEPH_CAP_OP_FLUSH, CEPH_CLIENT_CAPS_SYNC,
2220			   __ceph_caps_used(ci), __ceph_caps_wanted(ci),
2221			   (cap->issued | cap->implemented),
2222			   flushing, flush_tid, oldest_flush_tid);
2223		spin_unlock(&ci->i_ceph_lock);
2224
2225		__send_cap(mdsc, &arg, ci);
2226	} else {
2227		if (!list_empty(&ci->i_cap_flush_list)) {
2228			struct ceph_cap_flush *cf =
2229				list_last_entry(&ci->i_cap_flush_list,
2230						struct ceph_cap_flush, i_list);
2231			cf->wake = true;
2232			flush_tid = cf->tid;
2233		}
2234		flushing = ci->i_flushing_caps;
2235		spin_unlock(&ci->i_ceph_lock);
2236	}
2237out:
2238	if (session)
 
 
2239		mutex_unlock(&session->s_mutex);
2240
2241	*ptid = flush_tid;
2242	return flushing;
2243}
2244
2245/*
2246 * Return true if we've flushed caps through the given flush_tid.
2247 */
2248static int caps_are_flushed(struct inode *inode, u64 flush_tid)
2249{
2250	struct ceph_inode_info *ci = ceph_inode(inode);
2251	int ret = 1;
2252
2253	spin_lock(&ci->i_ceph_lock);
2254	if (!list_empty(&ci->i_cap_flush_list)) {
2255		struct ceph_cap_flush * cf =
2256			list_first_entry(&ci->i_cap_flush_list,
2257					 struct ceph_cap_flush, i_list);
2258		if (cf->tid <= flush_tid)
2259			ret = 0;
2260	}
 
2261	spin_unlock(&ci->i_ceph_lock);
2262	return ret;
2263}
2264
2265/*
2266 * wait for any unsafe requests to complete.
 
 
 
2267 */
2268static int unsafe_request_wait(struct inode *inode)
2269{
2270	struct ceph_inode_info *ci = ceph_inode(inode);
2271	struct ceph_mds_request *req1 = NULL, *req2 = NULL;
2272	int ret, err = 0;
 
2273
2274	spin_lock(&ci->i_unsafe_lock);
2275	if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) {
2276		req1 = list_last_entry(&ci->i_unsafe_dirops,
2277					struct ceph_mds_request,
2278					r_unsafe_dir_item);
2279		ceph_mdsc_get_request(req1);
2280	}
2281	if (!list_empty(&ci->i_unsafe_iops)) {
2282		req2 = list_last_entry(&ci->i_unsafe_iops,
2283					struct ceph_mds_request,
2284					r_unsafe_target_item);
2285		ceph_mdsc_get_request(req2);
2286	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2287	spin_unlock(&ci->i_unsafe_lock);
2288
2289	dout("unsafe_request_wait %p wait on tid %llu %llu\n",
2290	     inode, req1 ? req1->r_tid : 0ULL, req2 ? req2->r_tid : 0ULL);
2291	if (req1) {
2292		ret = !wait_for_completion_timeout(&req1->r_safe_completion,
2293					ceph_timeout_jiffies(req1->r_timeout));
2294		if (ret)
2295			err = -EIO;
2296		ceph_mdsc_put_request(req1);
2297	}
2298	if (req2) {
2299		ret = !wait_for_completion_timeout(&req2->r_safe_completion,
2300					ceph_timeout_jiffies(req2->r_timeout));
2301		if (ret)
2302			err = -EIO;
2303		ceph_mdsc_put_request(req2);
2304	}
2305	return err;
2306}
2307
2308int ceph_fsync(struct file *file, loff_t start, loff_t end, int datasync)
2309{
2310	struct ceph_file_info *fi = file->private_data;
2311	struct inode *inode = file->f_mapping->host;
2312	struct ceph_inode_info *ci = ceph_inode(inode);
2313	u64 flush_tid;
2314	int ret, err;
2315	int dirty;
2316
2317	dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
 
2318
2319	ret = file_write_and_wait_range(file, start, end);
2320	if (datasync)
2321		goto out;
2322
2323	ret = ceph_wait_on_async_create(inode);
2324	if (ret)
2325		goto out;
2326
2327	dirty = try_flush_caps(inode, &flush_tid);
2328	dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
2329
2330	err = unsafe_request_wait(inode);
2331
2332	/*
2333	 * only wait on non-file metadata writeback (the mds
2334	 * can recover size and mtime, so we don't need to
2335	 * wait for that)
2336	 */
2337	if (!err && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
2338		err = wait_event_interruptible(ci->i_cap_wq,
2339					caps_are_flushed(inode, flush_tid));
 
2340	}
2341
2342	if (err < 0)
2343		ret = err;
2344
2345	if (errseq_check(&ci->i_meta_err, READ_ONCE(fi->meta_err))) {
2346		spin_lock(&file->f_lock);
2347		err = errseq_check_and_advance(&ci->i_meta_err,
2348					       &fi->meta_err);
2349		spin_unlock(&file->f_lock);
2350		if (err < 0)
2351			ret = err;
2352	}
2353out:
2354	dout("fsync %p%s result=%d\n", inode, datasync ? " datasync" : "", ret);
2355	return ret;
2356}
2357
2358/*
2359 * Flush any dirty caps back to the mds.  If we aren't asked to wait,
2360 * queue inode for flush but don't do so immediately, because we can
2361 * get by with fewer MDS messages if we wait for data writeback to
2362 * complete first.
2363 */
2364int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
2365{
2366	struct ceph_inode_info *ci = ceph_inode(inode);
2367	u64 flush_tid;
2368	int err = 0;
2369	int dirty;
2370	int wait = (wbc->sync_mode == WB_SYNC_ALL && !wbc->for_sync);
2371
2372	dout("write_inode %p wait=%d\n", inode, wait);
2373	if (wait) {
2374		dirty = try_flush_caps(inode, &flush_tid);
2375		if (dirty)
2376			err = wait_event_interruptible(ci->i_cap_wq,
2377				       caps_are_flushed(inode, flush_tid));
2378	} else {
2379		struct ceph_mds_client *mdsc =
2380			ceph_sb_to_client(inode->i_sb)->mdsc;
2381
2382		spin_lock(&ci->i_ceph_lock);
2383		if (__ceph_caps_dirty(ci))
2384			__cap_delay_requeue_front(mdsc, ci);
2385		spin_unlock(&ci->i_ceph_lock);
2386	}
2387	return err;
2388}
2389
2390static void __kick_flushing_caps(struct ceph_mds_client *mdsc,
2391				 struct ceph_mds_session *session,
2392				 struct ceph_inode_info *ci,
2393				 u64 oldest_flush_tid)
2394	__releases(ci->i_ceph_lock)
2395	__acquires(ci->i_ceph_lock)
2396{
2397	struct inode *inode = &ci->vfs_inode;
2398	struct ceph_cap *cap;
2399	struct ceph_cap_flush *cf;
2400	int ret;
2401	u64 first_tid = 0;
2402	u64 last_snap_flush = 0;
2403
2404	ci->i_ceph_flags &= ~CEPH_I_KICK_FLUSH;
2405
2406	list_for_each_entry_reverse(cf, &ci->i_cap_flush_list, i_list) {
2407		if (!cf->caps) {
2408			last_snap_flush = cf->tid;
2409			break;
2410		}
2411	}
2412
2413	list_for_each_entry(cf, &ci->i_cap_flush_list, i_list) {
2414		if (cf->tid < first_tid)
2415			continue;
2416
2417		cap = ci->i_auth_cap;
2418		if (!(cap && cap->session == session)) {
2419			pr_err("%p auth cap %p not mds%d ???\n",
2420			       inode, cap, session->s_mds);
2421			break;
2422		}
2423
2424		first_tid = cf->tid + 1;
2425
2426		if (cf->caps) {
2427			struct cap_msg_args arg;
2428
2429			dout("kick_flushing_caps %p cap %p tid %llu %s\n",
2430			     inode, cap, cf->tid, ceph_cap_string(cf->caps));
2431			__prep_cap(&arg, cap, CEPH_CAP_OP_FLUSH,
2432					 (cf->tid < last_snap_flush ?
2433					  CEPH_CLIENT_CAPS_PENDING_CAPSNAP : 0),
2434					  __ceph_caps_used(ci),
2435					  __ceph_caps_wanted(ci),
2436					  (cap->issued | cap->implemented),
2437					  cf->caps, cf->tid, oldest_flush_tid);
2438			spin_unlock(&ci->i_ceph_lock);
2439			__send_cap(mdsc, &arg, ci);
2440		} else {
2441			struct ceph_cap_snap *capsnap =
2442					container_of(cf, struct ceph_cap_snap,
2443						    cap_flush);
2444			dout("kick_flushing_caps %p capsnap %p tid %llu %s\n",
2445			     inode, capsnap, cf->tid,
2446			     ceph_cap_string(capsnap->dirty));
2447
2448			refcount_inc(&capsnap->nref);
2449			spin_unlock(&ci->i_ceph_lock);
2450
2451			ret = __send_flush_snap(inode, session, capsnap, cap->mseq,
2452						oldest_flush_tid);
2453			if (ret < 0) {
2454				pr_err("kick_flushing_caps: error sending "
2455					"cap flushsnap, ino (%llx.%llx) "
2456					"tid %llu follows %llu\n",
2457					ceph_vinop(inode), cf->tid,
2458					capsnap->follows);
2459			}
2460
2461			ceph_put_cap_snap(capsnap);
2462		}
2463
2464		spin_lock(&ci->i_ceph_lock);
2465	}
2466}
2467
2468void ceph_early_kick_flushing_caps(struct ceph_mds_client *mdsc,
2469				   struct ceph_mds_session *session)
2470{
2471	struct ceph_inode_info *ci;
2472	struct ceph_cap *cap;
2473	u64 oldest_flush_tid;
2474
2475	dout("early_kick_flushing_caps mds%d\n", session->s_mds);
 
 
 
 
 
2476
2477	spin_lock(&mdsc->cap_dirty_lock);
2478	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2479	spin_unlock(&mdsc->cap_dirty_lock);
2480
2481	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2482		spin_lock(&ci->i_ceph_lock);
2483		cap = ci->i_auth_cap;
2484		if (!(cap && cap->session == session)) {
2485			pr_err("%p auth cap %p not mds%d ???\n",
2486				&ci->vfs_inode, cap, session->s_mds);
2487			spin_unlock(&ci->i_ceph_lock);
2488			continue;
2489		}
2490
2491
2492		/*
2493		 * if flushing caps were revoked, we re-send the cap flush
2494		 * in client reconnect stage. This guarantees MDS * processes
2495		 * the cap flush message before issuing the flushing caps to
2496		 * other client.
2497		 */
2498		if ((cap->issued & ci->i_flushing_caps) !=
2499		    ci->i_flushing_caps) {
2500			/* encode_caps_cb() also will reset these sequence
2501			 * numbers. make sure sequence numbers in cap flush
2502			 * message match later reconnect message */
2503			cap->seq = 0;
2504			cap->issue_seq = 0;
2505			cap->mseq = 0;
2506			__kick_flushing_caps(mdsc, session, ci,
2507					     oldest_flush_tid);
2508		} else {
2509			ci->i_ceph_flags |= CEPH_I_KICK_FLUSH;
 
2510		}
2511
2512		spin_unlock(&ci->i_ceph_lock);
2513	}
2514}
2515
2516void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
2517			     struct ceph_mds_session *session)
2518{
2519	struct ceph_inode_info *ci;
2520	struct ceph_cap *cap;
2521	u64 oldest_flush_tid;
2522
2523	lockdep_assert_held(&session->s_mutex);
2524
2525	dout("kick_flushing_caps mds%d\n", session->s_mds);
 
 
 
 
2526
2527	spin_lock(&mdsc->cap_dirty_lock);
2528	oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2529	spin_unlock(&mdsc->cap_dirty_lock);
2530
2531	list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
2532		spin_lock(&ci->i_ceph_lock);
2533		cap = ci->i_auth_cap;
2534		if (!(cap && cap->session == session)) {
2535			pr_err("%p auth cap %p not mds%d ???\n",
2536				&ci->vfs_inode, cap, session->s_mds);
 
 
 
 
 
 
 
 
 
 
 
 
 
2537			spin_unlock(&ci->i_ceph_lock);
2538			continue;
2539		}
2540		if (ci->i_ceph_flags & CEPH_I_KICK_FLUSH) {
2541			__kick_flushing_caps(mdsc, session, ci,
2542					     oldest_flush_tid);
2543		}
2544		spin_unlock(&ci->i_ceph_lock);
2545	}
2546}
2547
2548void ceph_kick_flushing_inode_caps(struct ceph_mds_session *session,
2549				   struct ceph_inode_info *ci)
 
2550{
2551	struct ceph_mds_client *mdsc = session->s_mdsc;
2552	struct ceph_cap *cap = ci->i_auth_cap;
 
2553
2554	lockdep_assert_held(&ci->i_ceph_lock);
2555
2556	dout("%s %p flushing %s\n", __func__, &ci->vfs_inode,
2557	     ceph_cap_string(ci->i_flushing_caps));
2558
2559	if (!list_empty(&ci->i_cap_flush_list)) {
2560		u64 oldest_flush_tid;
2561		spin_lock(&mdsc->cap_dirty_lock);
2562		list_move_tail(&ci->i_flushing_item,
2563			       &cap->session->s_cap_flushing);
2564		oldest_flush_tid = __get_oldest_flush_tid(mdsc);
2565		spin_unlock(&mdsc->cap_dirty_lock);
2566
2567		__kick_flushing_caps(mdsc, session, ci, oldest_flush_tid);
 
 
 
 
2568	}
2569}
2570
2571
2572/*
2573 * Take references to capabilities we hold, so that we don't release
2574 * them to the MDS prematurely.
 
 
2575 */
2576void ceph_take_cap_refs(struct ceph_inode_info *ci, int got,
2577			    bool snap_rwsem_locked)
2578{
2579	lockdep_assert_held(&ci->i_ceph_lock);
2580
2581	if (got & CEPH_CAP_PIN)
2582		ci->i_pin_ref++;
2583	if (got & CEPH_CAP_FILE_RD)
2584		ci->i_rd_ref++;
2585	if (got & CEPH_CAP_FILE_CACHE)
2586		ci->i_rdcache_ref++;
2587	if (got & CEPH_CAP_FILE_EXCL)
2588		ci->i_fx_ref++;
2589	if (got & CEPH_CAP_FILE_WR) {
2590		if (ci->i_wr_ref == 0 && !ci->i_head_snapc) {
2591			BUG_ON(!snap_rwsem_locked);
2592			ci->i_head_snapc = ceph_get_snap_context(
2593					ci->i_snap_realm->cached_context);
2594		}
2595		ci->i_wr_ref++;
2596	}
2597	if (got & CEPH_CAP_FILE_BUFFER) {
2598		if (ci->i_wb_ref == 0)
2599			ihold(&ci->vfs_inode);
2600		ci->i_wb_ref++;
2601		dout("%s %p wb %d -> %d (?)\n", __func__,
2602		     &ci->vfs_inode, ci->i_wb_ref-1, ci->i_wb_ref);
2603	}
2604}
2605
2606/*
2607 * Try to grab cap references.  Specify those refs we @want, and the
2608 * minimal set we @need.  Also include the larger offset we are writing
2609 * to (when applicable), and check against max_size here as well.
2610 * Note that caller is responsible for ensuring max_size increases are
2611 * requested from the MDS.
2612 *
2613 * Returns 0 if caps were not able to be acquired (yet), 1 if succeed,
2614 * or a negative error code. There are 3 speical error codes:
2615 *  -EAGAIN: need to sleep but non-blocking is specified
2616 *  -EFBIG:  ask caller to call check_max_size() and try again.
2617 *  -ESTALE: ask caller to call ceph_renew_caps() and try again.
2618 */
2619enum {
2620	/* first 8 bits are reserved for CEPH_FILE_MODE_FOO */
2621	NON_BLOCKING	= (1 << 8),
2622	CHECK_FILELOCK	= (1 << 9),
2623};
2624
2625static int try_get_cap_refs(struct inode *inode, int need, int want,
2626			    loff_t endoff, int flags, int *got)
2627{
2628	struct ceph_inode_info *ci = ceph_inode(inode);
2629	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
2630	int ret = 0;
2631	int have, implemented;
2632	bool snap_rwsem_locked = false;
2633
2634	dout("get_cap_refs %p need %s want %s\n", inode,
2635	     ceph_cap_string(need), ceph_cap_string(want));
2636
2637again:
2638	spin_lock(&ci->i_ceph_lock);
2639
2640	if ((flags & CHECK_FILELOCK) &&
2641	    (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK)) {
2642		dout("try_get_cap_refs %p error filelock\n", inode);
2643		ret = -EIO;
2644		goto out_unlock;
 
 
 
2645	}
2646
2647	/* finish pending truncate */
2648	while (ci->i_truncate_pending) {
2649		spin_unlock(&ci->i_ceph_lock);
2650		if (snap_rwsem_locked) {
2651			up_read(&mdsc->snap_rwsem);
2652			snap_rwsem_locked = false;
2653		}
2654		__ceph_do_pending_vmtruncate(inode);
2655		spin_lock(&ci->i_ceph_lock);
2656	}
2657
2658	have = __ceph_caps_issued(ci, &implemented);
2659
2660	if (have & need & CEPH_CAP_FILE_WR) {
2661		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
2662			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
2663			     inode, endoff, ci->i_max_size);
2664			if (endoff > ci->i_requested_max_size)
2665				ret = ci->i_auth_cap ? -EFBIG : -ESTALE;
2666			goto out_unlock;
 
 
2667		}
2668		/*
2669		 * If a sync write is in progress, we must wait, so that we
2670		 * can get a final snapshot value for size+mtime.
2671		 */
2672		if (__ceph_have_pending_cap_snap(ci)) {
2673			dout("get_cap_refs %p cap_snap_pending\n", inode);
2674			goto out_unlock;
2675		}
2676	}
 
 
 
 
 
 
 
2677
2678	if ((have & need) == need) {
2679		/*
2680		 * Look at (implemented & ~have & not) so that we keep waiting
2681		 * on transition from wanted -> needed caps.  This is needed
2682		 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2683		 * going before a prior buffered writeback happens.
2684		 */
2685		int not = want & ~(have & need);
2686		int revoking = implemented & ~have;
2687		dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2688		     inode, ceph_cap_string(have), ceph_cap_string(not),
2689		     ceph_cap_string(revoking));
2690		if ((revoking & not) == 0) {
2691			if (!snap_rwsem_locked &&
2692			    !ci->i_head_snapc &&
2693			    (need & CEPH_CAP_FILE_WR)) {
2694				if (!down_read_trylock(&mdsc->snap_rwsem)) {
2695					/*
2696					 * we can not call down_read() when
2697					 * task isn't in TASK_RUNNING state
2698					 */
2699					if (flags & NON_BLOCKING) {
2700						ret = -EAGAIN;
2701						goto out_unlock;
2702					}
2703
2704					spin_unlock(&ci->i_ceph_lock);
2705					down_read(&mdsc->snap_rwsem);
2706					snap_rwsem_locked = true;
2707					goto again;
2708				}
2709				snap_rwsem_locked = true;
2710			}
2711			if ((have & want) == want)
2712				*got = need | want;
2713			else
2714				*got = need;
2715			if (S_ISREG(inode->i_mode) &&
2716			    (need & CEPH_CAP_FILE_RD) &&
2717			    !(*got & CEPH_CAP_FILE_CACHE))
2718				ceph_disable_fscache_readpage(ci);
2719			ceph_take_cap_refs(ci, *got, true);
2720			ret = 1;
2721		}
2722	} else {
2723		int session_readonly = false;
2724		int mds_wanted;
2725		if (ci->i_auth_cap &&
2726		    (need & (CEPH_CAP_FILE_WR | CEPH_CAP_FILE_EXCL))) {
2727			struct ceph_mds_session *s = ci->i_auth_cap->session;
2728			spin_lock(&s->s_cap_lock);
2729			session_readonly = s->s_readonly;
2730			spin_unlock(&s->s_cap_lock);
2731		}
2732		if (session_readonly) {
2733			dout("get_cap_refs %p need %s but mds%d readonly\n",
2734			     inode, ceph_cap_string(need), ci->i_auth_cap->mds);
2735			ret = -EROFS;
2736			goto out_unlock;
2737		}
2738
2739		if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
2740			dout("get_cap_refs %p forced umount\n", inode);
2741			ret = -EIO;
2742			goto out_unlock;
2743		}
2744		mds_wanted = __ceph_caps_mds_wanted(ci, false);
2745		if (need & ~mds_wanted) {
2746			dout("get_cap_refs %p need %s > mds_wanted %s\n",
2747			     inode, ceph_cap_string(need),
2748			     ceph_cap_string(mds_wanted));
2749			ret = -ESTALE;
2750			goto out_unlock;
2751		}
2752
2753		dout("get_cap_refs %p have %s need %s\n", inode,
2754		     ceph_cap_string(have), ceph_cap_string(need));
2755	}
2756out_unlock:
2757
2758	__ceph_touch_fmode(ci, mdsc, flags);
2759
2760	spin_unlock(&ci->i_ceph_lock);
2761	if (snap_rwsem_locked)
2762		up_read(&mdsc->snap_rwsem);
2763
2764	if (!ret)
2765		ceph_update_cap_mis(&mdsc->metric);
2766	else if (ret == 1)
2767		ceph_update_cap_hit(&mdsc->metric);
2768
2769	dout("get_cap_refs %p ret %d got %s\n", inode,
2770	     ret, ceph_cap_string(*got));
2771	return ret;
2772}
2773
2774/*
2775 * Check the offset we are writing up to against our current
2776 * max_size.  If necessary, tell the MDS we want to write to
2777 * a larger offset.
2778 */
2779static void check_max_size(struct inode *inode, loff_t endoff)
2780{
2781	struct ceph_inode_info *ci = ceph_inode(inode);
2782	int check = 0;
2783
2784	/* do we need to explicitly request a larger max_size? */
2785	spin_lock(&ci->i_ceph_lock);
2786	if (endoff >= ci->i_max_size && endoff > ci->i_wanted_max_size) {
 
 
2787		dout("write %p at large endoff %llu, req max_size\n",
2788		     inode, endoff);
2789		ci->i_wanted_max_size = endoff;
 
2790	}
2791	/* duplicate ceph_check_caps()'s logic */
2792	if (ci->i_auth_cap &&
2793	    (ci->i_auth_cap->issued & CEPH_CAP_FILE_WR) &&
2794	    ci->i_wanted_max_size > ci->i_max_size &&
2795	    ci->i_wanted_max_size > ci->i_requested_max_size)
2796		check = 1;
2797	spin_unlock(&ci->i_ceph_lock);
2798	if (check)
2799		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2800}
2801
2802static inline int get_used_fmode(int caps)
2803{
2804	int fmode = 0;
2805	if (caps & CEPH_CAP_FILE_RD)
2806		fmode |= CEPH_FILE_MODE_RD;
2807	if (caps & CEPH_CAP_FILE_WR)
2808		fmode |= CEPH_FILE_MODE_WR;
2809	return fmode;
2810}
2811
2812int ceph_try_get_caps(struct inode *inode, int need, int want,
2813		      bool nonblock, int *got)
2814{
2815	int ret, flags;
2816
2817	BUG_ON(need & ~CEPH_CAP_FILE_RD);
2818	BUG_ON(want & ~(CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO |
2819			CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL |
2820			CEPH_CAP_ANY_DIR_OPS));
2821	if (need) {
2822		ret = ceph_pool_perm_check(inode, need);
2823		if (ret < 0)
2824			return ret;
2825	}
2826
2827	flags = get_used_fmode(need | want);
2828	if (nonblock)
2829		flags |= NON_BLOCKING;
2830
2831	ret = try_get_cap_refs(inode, need, want, 0, flags, got);
2832	/* three special error codes */
2833	if (ret == -EAGAIN || ret == -EFBIG || ret == -ESTALE)
2834		ret = 0;
2835	return ret;
2836}
2837
2838/*
2839 * Wait for caps, and take cap references.  If we can't get a WR cap
2840 * due to a small max_size, make sure we check_max_size (and possibly
2841 * ask the mds) so we don't get hung up indefinitely.
2842 */
2843int ceph_get_caps(struct file *filp, int need, int want,
2844		  loff_t endoff, int *got, struct page **pinned_page)
2845{
2846	struct ceph_file_info *fi = filp->private_data;
2847	struct inode *inode = file_inode(filp);
2848	struct ceph_inode_info *ci = ceph_inode(inode);
2849	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
2850	int ret, _got, flags;
2851
2852	ret = ceph_pool_perm_check(inode, need);
2853	if (ret < 0)
2854		return ret;
2855
2856	if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2857	    fi->filp_gen != READ_ONCE(fsc->filp_gen))
2858		return -EBADF;
2859
2860	flags = get_used_fmode(need | want);
2861
2862	while (true) {
2863		flags &= CEPH_FILE_MODE_MASK;
2864		if (atomic_read(&fi->num_locks))
2865			flags |= CHECK_FILELOCK;
2866		_got = 0;
2867		ret = try_get_cap_refs(inode, need, want, endoff,
2868				       flags, &_got);
2869		WARN_ON_ONCE(ret == -EAGAIN);
2870		if (!ret) {
2871			struct ceph_mds_client *mdsc = fsc->mdsc;
2872			struct cap_wait cw;
2873			DEFINE_WAIT_FUNC(wait, woken_wake_function);
2874
2875			cw.ino = ceph_ino(inode);
2876			cw.tgid = current->tgid;
2877			cw.need = need;
2878			cw.want = want;
2879
2880			spin_lock(&mdsc->caps_list_lock);
2881			list_add(&cw.list, &mdsc->cap_wait_list);
2882			spin_unlock(&mdsc->caps_list_lock);
2883
2884			/* make sure used fmode not timeout */
2885			ceph_get_fmode(ci, flags, FMODE_WAIT_BIAS);
2886			add_wait_queue(&ci->i_cap_wq, &wait);
2887
2888			flags |= NON_BLOCKING;
2889			while (!(ret = try_get_cap_refs(inode, need, want,
2890							endoff, flags, &_got))) {
2891				if (signal_pending(current)) {
2892					ret = -ERESTARTSYS;
2893					break;
2894				}
2895				wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
2896			}
2897
2898			remove_wait_queue(&ci->i_cap_wq, &wait);
2899			ceph_put_fmode(ci, flags, FMODE_WAIT_BIAS);
2900
2901			spin_lock(&mdsc->caps_list_lock);
2902			list_del(&cw.list);
2903			spin_unlock(&mdsc->caps_list_lock);
2904
2905			if (ret == -EAGAIN)
2906				continue;
2907		}
2908
2909		if ((fi->fmode & CEPH_FILE_MODE_WR) &&
2910		    fi->filp_gen != READ_ONCE(fsc->filp_gen)) {
2911			if (ret >= 0 && _got)
2912				ceph_put_cap_refs(ci, _got);
2913			return -EBADF;
2914		}
2915
2916		if (ret < 0) {
2917			if (ret == -EFBIG || ret == -ESTALE) {
2918				int ret2 = ceph_wait_on_async_create(inode);
2919				if (ret2 < 0)
2920					return ret2;
2921			}
2922			if (ret == -EFBIG) {
2923				check_max_size(inode, endoff);
2924				continue;
2925			}
2926			if (ret == -ESTALE) {
2927				/* session was killed, try renew caps */
2928				ret = ceph_renew_caps(inode, flags);
2929				if (ret == 0)
2930					continue;
2931			}
2932			return ret;
2933		}
2934
2935		if (S_ISREG(ci->vfs_inode.i_mode) &&
2936		    ci->i_inline_version != CEPH_INLINE_NONE &&
2937		    (_got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) &&
2938		    i_size_read(inode) > 0) {
2939			struct page *page =
2940				find_get_page(inode->i_mapping, 0);
2941			if (page) {
2942				if (PageUptodate(page)) {
2943					*pinned_page = page;
2944					break;
2945				}
2946				put_page(page);
2947			}
2948			/*
2949			 * drop cap refs first because getattr while
2950			 * holding * caps refs can cause deadlock.
2951			 */
2952			ceph_put_cap_refs(ci, _got);
2953			_got = 0;
2954
2955			/*
2956			 * getattr request will bring inline data into
2957			 * page cache
2958			 */
2959			ret = __ceph_do_getattr(inode, NULL,
2960						CEPH_STAT_CAP_INLINE_DATA,
2961						true);
2962			if (ret < 0)
2963				return ret;
2964			continue;
2965		}
2966		break;
2967	}
2968
2969	if (S_ISREG(ci->vfs_inode.i_mode) &&
2970	    (_got & CEPH_CAP_FILE_RD) && (_got & CEPH_CAP_FILE_CACHE))
2971		ceph_fscache_revalidate_cookie(ci);
2972
2973	*got = _got;
2974	return 0;
2975}
2976
2977/*
2978 * Take cap refs.  Caller must already know we hold at least one ref
2979 * on the caps in question or we don't know this is safe.
2980 */
2981void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2982{
2983	spin_lock(&ci->i_ceph_lock);
2984	ceph_take_cap_refs(ci, caps, false);
2985	spin_unlock(&ci->i_ceph_lock);
2986}
2987
2988
2989/*
2990 * drop cap_snap that is not associated with any snapshot.
2991 * we don't need to send FLUSHSNAP message for it.
2992 */
2993static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
2994				  struct ceph_cap_snap *capsnap)
2995{
2996	if (!capsnap->need_flush &&
2997	    !capsnap->writing && !capsnap->dirty_pages) {
2998		dout("dropping cap_snap %p follows %llu\n",
2999		     capsnap, capsnap->follows);
3000		BUG_ON(capsnap->cap_flush.tid > 0);
3001		ceph_put_snap_context(capsnap->context);
3002		if (!list_is_last(&capsnap->ci_item, &ci->i_cap_snaps))
3003			ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
3004
3005		list_del(&capsnap->ci_item);
3006		ceph_put_cap_snap(capsnap);
3007		return 1;
3008	}
3009	return 0;
3010}
3011
3012/*
3013 * Release cap refs.
3014 *
3015 * If we released the last ref on any given cap, call ceph_check_caps
3016 * to release (or schedule a release).
3017 *
3018 * If we are releasing a WR cap (from a sync write), finalize any affected
3019 * cap_snap, and wake up any waiters.
3020 */
3021static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had,
3022				bool skip_checking_caps)
3023{
3024	struct inode *inode = &ci->vfs_inode;
3025	int last = 0, put = 0, flushsnaps = 0, wake = 0;
 
3026
3027	spin_lock(&ci->i_ceph_lock);
3028	if (had & CEPH_CAP_PIN)
3029		--ci->i_pin_ref;
3030	if (had & CEPH_CAP_FILE_RD)
3031		if (--ci->i_rd_ref == 0)
3032			last++;
3033	if (had & CEPH_CAP_FILE_CACHE)
3034		if (--ci->i_rdcache_ref == 0)
3035			last++;
3036	if (had & CEPH_CAP_FILE_EXCL)
3037		if (--ci->i_fx_ref == 0)
3038			last++;
3039	if (had & CEPH_CAP_FILE_BUFFER) {
3040		if (--ci->i_wb_ref == 0) {
3041			last++;
3042			put++;
3043		}
3044		dout("put_cap_refs %p wb %d -> %d (?)\n",
3045		     inode, ci->i_wb_ref+1, ci->i_wb_ref);
3046	}
3047	if (had & CEPH_CAP_FILE_WR)
3048		if (--ci->i_wr_ref == 0) {
3049			last++;
3050			if (__ceph_have_pending_cap_snap(ci)) {
3051				struct ceph_cap_snap *capsnap =
3052					list_last_entry(&ci->i_cap_snaps,
3053							struct ceph_cap_snap,
3054							ci_item);
3055				capsnap->writing = 0;
3056				if (ceph_try_drop_cap_snap(ci, capsnap))
3057					put++;
3058				else if (__ceph_finish_cap_snap(ci, capsnap))
3059					flushsnaps = 1;
3060				wake = 1;
3061			}
3062			if (ci->i_wrbuffer_ref_head == 0 &&
3063			    ci->i_dirty_caps == 0 &&
3064			    ci->i_flushing_caps == 0) {
3065				BUG_ON(!ci->i_head_snapc);
3066				ceph_put_snap_context(ci->i_head_snapc);
3067				ci->i_head_snapc = NULL;
3068			}
3069			/* see comment in __ceph_remove_cap() */
3070			if (!__ceph_is_any_real_caps(ci) && ci->i_snap_realm)
3071				drop_inode_snap_realm(ci);
3072		}
3073	spin_unlock(&ci->i_ceph_lock);
3074
3075	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
3076	     last ? " last" : "", put ? " put" : "");
3077
3078	if (last && !skip_checking_caps)
3079		ceph_check_caps(ci, 0, NULL);
3080	else if (flushsnaps)
3081		ceph_flush_snaps(ci, NULL);
3082	if (wake)
3083		wake_up_all(&ci->i_cap_wq);
3084	while (put-- > 0)
3085		iput(inode);
3086}
3087
3088void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
3089{
3090	__ceph_put_cap_refs(ci, had, false);
3091}
3092
3093void ceph_put_cap_refs_no_check_caps(struct ceph_inode_info *ci, int had)
3094{
3095	__ceph_put_cap_refs(ci, had, true);
3096}
3097
3098/*
3099 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
3100 * context.  Adjust per-snap dirty page accounting as appropriate.
3101 * Once all dirty data for a cap_snap is flushed, flush snapped file
3102 * metadata back to the MDS.  If we dropped the last ref, call
3103 * ceph_check_caps.
3104 */
3105void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
3106				struct ceph_snap_context *snapc)
3107{
3108	struct inode *inode = &ci->vfs_inode;
 
 
 
 
3109	struct ceph_cap_snap *capsnap = NULL;
3110	int put = 0;
3111	bool last = false;
3112	bool found = false;
3113	bool flush_snaps = false;
3114	bool complete_capsnap = false;
3115
3116	spin_lock(&ci->i_ceph_lock);
3117	ci->i_wrbuffer_ref -= nr;
3118	if (ci->i_wrbuffer_ref == 0) {
3119		last = true;
3120		put++;
3121	}
3122
3123	if (ci->i_head_snapc == snapc) {
3124		ci->i_wrbuffer_ref_head -= nr;
3125		if (ci->i_wrbuffer_ref_head == 0 &&
3126		    ci->i_wr_ref == 0 &&
3127		    ci->i_dirty_caps == 0 &&
3128		    ci->i_flushing_caps == 0) {
3129			BUG_ON(!ci->i_head_snapc);
3130			ceph_put_snap_context(ci->i_head_snapc);
3131			ci->i_head_snapc = NULL;
3132		}
3133		dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
3134		     inode,
3135		     ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
3136		     ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
3137		     last ? " LAST" : "");
3138	} else {
3139		list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
3140			if (capsnap->context == snapc) {
3141				found = true;
3142				break;
3143			}
3144		}
3145		BUG_ON(!found);
3146		capsnap->dirty_pages -= nr;
3147		if (capsnap->dirty_pages == 0) {
3148			complete_capsnap = true;
3149			if (!capsnap->writing) {
3150				if (ceph_try_drop_cap_snap(ci, capsnap)) {
3151					put++;
3152				} else {
3153					ci->i_ceph_flags |= CEPH_I_FLUSH_SNAPS;
3154					flush_snaps = true;
3155				}
3156			}
3157		}
3158		dout("put_wrbuffer_cap_refs on %p cap_snap %p "
3159		     " snap %lld %d/%d -> %d/%d %s%s\n",
3160		     inode, capsnap, capsnap->context->seq,
3161		     ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
3162		     ci->i_wrbuffer_ref, capsnap->dirty_pages,
3163		     last ? " (wrbuffer last)" : "",
3164		     complete_capsnap ? " (complete capsnap)" : "");
 
 
 
 
 
 
 
3165	}
3166
3167	spin_unlock(&ci->i_ceph_lock);
3168
3169	if (last) {
3170		ceph_check_caps(ci, 0, NULL);
3171	} else if (flush_snaps) {
3172		ceph_flush_snaps(ci, NULL);
3173	}
3174	if (complete_capsnap)
3175		wake_up_all(&ci->i_cap_wq);
3176	while (put-- > 0) {
3177		/* avoid calling iput_final() in osd dispatch threads */
3178		ceph_async_iput(inode);
3179	}
 
 
3180}
3181
3182/*
3183 * Invalidate unlinked inode's aliases, so we can drop the inode ASAP.
3184 */
3185static void invalidate_aliases(struct inode *inode)
3186{
3187	struct dentry *dn, *prev = NULL;
3188
3189	dout("invalidate_aliases inode %p\n", inode);
3190	d_prune_aliases(inode);
3191	/*
3192	 * For non-directory inode, d_find_alias() only returns
3193	 * hashed dentry. After calling d_invalidate(), the
3194	 * dentry becomes unhashed.
3195	 *
3196	 * For directory inode, d_find_alias() can return
3197	 * unhashed dentry. But directory inode should have
3198	 * one alias at most.
3199	 */
3200	while ((dn = d_find_alias(inode))) {
3201		if (dn == prev) {
3202			dput(dn);
3203			break;
3204		}
3205		d_invalidate(dn);
3206		if (prev)
3207			dput(prev);
3208		prev = dn;
3209	}
3210	if (prev)
3211		dput(prev);
3212}
3213
3214struct cap_extra_info {
3215	struct ceph_string *pool_ns;
3216	/* inline data */
3217	u64 inline_version;
3218	void *inline_data;
3219	u32 inline_len;
3220	/* dirstat */
3221	bool dirstat_valid;
3222	u64 nfiles;
3223	u64 nsubdirs;
3224	u64 change_attr;
3225	/* currently issued */
3226	int issued;
3227	struct timespec64 btime;
3228};
3229
3230/*
3231 * Handle a cap GRANT message from the MDS.  (Note that a GRANT may
3232 * actually be a revocation if it specifies a smaller cap set.)
3233 *
3234 * caller holds s_mutex and i_ceph_lock, we drop both.
 
 
 
 
 
3235 */
3236static void handle_cap_grant(struct inode *inode,
3237			     struct ceph_mds_session *session,
3238			     struct ceph_cap *cap,
3239			     struct ceph_mds_caps *grant,
3240			     struct ceph_buffer *xattr_buf,
3241			     struct cap_extra_info *extra_info)
3242	__releases(ci->i_ceph_lock)
3243	__releases(session->s_mdsc->snap_rwsem)
3244{
3245	struct ceph_inode_info *ci = ceph_inode(inode);
 
3246	int seq = le32_to_cpu(grant->seq);
3247	int newcaps = le32_to_cpu(grant->caps);
3248	int used, wanted, dirty;
3249	u64 size = le64_to_cpu(grant->size);
3250	u64 max_size = le64_to_cpu(grant->max_size);
3251	unsigned char check_caps = 0;
3252	bool was_stale = cap->cap_gen < session->s_cap_gen;
3253	bool wake = false;
3254	bool writeback = false;
3255	bool queue_trunc = false;
3256	bool queue_invalidate = false;
3257	bool deleted_inode = false;
3258	bool fill_inline = false;
3259
3260	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
3261	     inode, cap, session->s_mds, seq, ceph_cap_string(newcaps));
3262	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
3263		inode->i_size);
3264
3265
3266	/*
3267	 * If CACHE is being revoked, and we have no dirty buffers,
3268	 * try to invalidate (once).  (If there are dirty buffers, we
3269	 * will invalidate _after_ writeback.)
3270	 */
3271	if (S_ISREG(inode->i_mode) && /* don't invalidate readdir cache */
3272	    ((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
3273	    (newcaps & CEPH_CAP_FILE_LAZYIO) == 0 &&
3274	    !(ci->i_wrbuffer_ref || ci->i_wb_ref)) {
3275		if (try_nonblocking_invalidate(inode)) {
 
 
3276			/* there were locked pages.. invalidate later
3277			   in a separate thread. */
3278			if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
3279				queue_invalidate = true;
3280				ci->i_rdcache_revoking = ci->i_rdcache_gen;
3281			}
3282		}
3283	}
3284
3285	if (was_stale)
3286		cap->issued = cap->implemented = CEPH_CAP_PIN;
3287
3288	/*
3289	 * auth mds of the inode changed. we received the cap export message,
3290	 * but still haven't received the cap import message. handle_cap_export
3291	 * updated the new auth MDS' cap.
3292	 *
3293	 * "ceph_seq_cmp(seq, cap->seq) <= 0" means we are processing a message
3294	 * that was sent before the cap import message. So don't remove caps.
3295	 */
3296	if (ceph_seq_cmp(seq, cap->seq) <= 0) {
3297		WARN_ON(cap != ci->i_auth_cap);
3298		WARN_ON(cap->cap_id != le64_to_cpu(grant->cap_id));
3299		seq = cap->seq;
3300		newcaps |= cap->issued;
3301	}
3302
3303	/* side effects now are allowed */
3304	cap->cap_gen = session->s_cap_gen;
3305	cap->seq = seq;
3306
3307	__check_cap_issue(ci, cap, newcaps);
3308
3309	inode_set_max_iversion_raw(inode, extra_info->change_attr);
3310
3311	if ((newcaps & CEPH_CAP_AUTH_SHARED) &&
3312	    (extra_info->issued & CEPH_CAP_AUTH_EXCL) == 0) {
3313		inode->i_mode = le32_to_cpu(grant->mode);
3314		inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(grant->uid));
3315		inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(grant->gid));
3316		ci->i_btime = extra_info->btime;
3317		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
3318		     from_kuid(&init_user_ns, inode->i_uid),
3319		     from_kgid(&init_user_ns, inode->i_gid));
3320	}
3321
3322	if ((newcaps & CEPH_CAP_LINK_SHARED) &&
3323	    (extra_info->issued & CEPH_CAP_LINK_EXCL) == 0) {
3324		set_nlink(inode, le32_to_cpu(grant->nlink));
3325		if (inode->i_nlink == 0 &&
3326		    (newcaps & (CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL)))
3327			deleted_inode = true;
3328	}
3329
3330	if ((extra_info->issued & CEPH_CAP_XATTR_EXCL) == 0 &&
3331	    grant->xattr_len) {
3332		int len = le32_to_cpu(grant->xattr_len);
3333		u64 version = le64_to_cpu(grant->xattr_version);
3334
3335		if (version > ci->i_xattrs.version) {
3336			dout(" got new xattrs v%llu on %p len %d\n",
3337			     version, inode, len);
3338			if (ci->i_xattrs.blob)
3339				ceph_buffer_put(ci->i_xattrs.blob);
3340			ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
3341			ci->i_xattrs.version = version;
3342			ceph_forget_all_cached_acls(inode);
3343			ceph_security_invalidate_secctx(inode);
3344		}
3345	}
3346
3347	if (newcaps & CEPH_CAP_ANY_RD) {
3348		struct timespec64 mtime, atime, ctime;
3349		/* ctime/mtime/atime? */
3350		ceph_decode_timespec64(&mtime, &grant->mtime);
3351		ceph_decode_timespec64(&atime, &grant->atime);
3352		ceph_decode_timespec64(&ctime, &grant->ctime);
3353		ceph_fill_file_time(inode, extra_info->issued,
3354				    le32_to_cpu(grant->time_warp_seq),
3355				    &ctime, &mtime, &atime);
3356	}
3357
3358	if ((newcaps & CEPH_CAP_FILE_SHARED) && extra_info->dirstat_valid) {
3359		ci->i_files = extra_info->nfiles;
3360		ci->i_subdirs = extra_info->nsubdirs;
3361	}
3362
3363	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
3364		/* file layout may have changed */
3365		s64 old_pool = ci->i_layout.pool_id;
3366		struct ceph_string *old_ns;
3367
3368		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
3369		old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
3370					lockdep_is_held(&ci->i_ceph_lock));
3371		rcu_assign_pointer(ci->i_layout.pool_ns, extra_info->pool_ns);
3372
3373		if (ci->i_layout.pool_id != old_pool ||
3374		    extra_info->pool_ns != old_ns)
3375			ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
3376
3377		extra_info->pool_ns = old_ns;
3378
3379		/* size/truncate_seq? */
3380		queue_trunc = ceph_fill_file_size(inode, extra_info->issued,
3381					le32_to_cpu(grant->truncate_seq),
3382					le64_to_cpu(grant->truncate_size),
3383					size);
3384	}
3385
3386	if (ci->i_auth_cap == cap && (newcaps & CEPH_CAP_ANY_FILE_WR)) {
3387		if (max_size != ci->i_max_size) {
3388			dout("max_size %lld -> %llu\n",
3389			     ci->i_max_size, max_size);
3390			ci->i_max_size = max_size;
3391			if (max_size >= ci->i_wanted_max_size) {
3392				ci->i_wanted_max_size = 0;  /* reset */
3393				ci->i_requested_max_size = 0;
3394			}
3395			wake = true;
3396		}
 
3397	}
3398
3399	/* check cap bits */
3400	wanted = __ceph_caps_wanted(ci);
3401	used = __ceph_caps_used(ci);
3402	dirty = __ceph_caps_dirty(ci);
3403	dout(" my wanted = %s, used = %s, dirty %s\n",
3404	     ceph_cap_string(wanted),
3405	     ceph_cap_string(used),
3406	     ceph_cap_string(dirty));
 
 
 
 
 
 
 
 
3407
3408	if ((was_stale || le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) &&
3409	    (wanted & ~(cap->mds_wanted | newcaps))) {
3410		/*
3411		 * If mds is importing cap, prior cap messages that update
3412		 * 'wanted' may get dropped by mds (migrate seq mismatch).
3413		 *
3414		 * We don't send cap message to update 'wanted' if what we
3415		 * want are already issued. If mds revokes caps, cap message
3416		 * that releases caps also tells mds what we want. But if
3417		 * caps got revoked by mds forcedly (session stale). We may
3418		 * haven't told mds what we want.
3419		 */
3420		check_caps = 1;
3421	}
3422
3423	/* revocation, grant, or no-op? */
3424	if (cap->issued & ~newcaps) {
3425		int revoking = cap->issued & ~newcaps;
3426
3427		dout("revocation: %s -> %s (revoking %s)\n",
3428		     ceph_cap_string(cap->issued),
3429		     ceph_cap_string(newcaps),
3430		     ceph_cap_string(revoking));
3431		if (S_ISREG(inode->i_mode) &&
3432		    (revoking & used & CEPH_CAP_FILE_BUFFER))
3433			writeback = true;  /* initiate writeback; will delay ack */
3434		else if (queue_invalidate &&
3435			 revoking == CEPH_CAP_FILE_CACHE &&
3436			 (newcaps & CEPH_CAP_FILE_LAZYIO) == 0)
3437			; /* do nothing yet, invalidation will be queued */
3438		else if (cap == ci->i_auth_cap)
3439			check_caps = 1; /* check auth cap only */
3440		else
3441			check_caps = 2; /* check all caps */
3442		cap->issued = newcaps;
3443		cap->implemented |= newcaps;
3444	} else if (cap->issued == newcaps) {
3445		dout("caps unchanged: %s -> %s\n",
3446		     ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
3447	} else {
3448		dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
3449		     ceph_cap_string(newcaps));
3450		/* non-auth MDS is revoking the newly grant caps ? */
3451		if (cap == ci->i_auth_cap &&
3452		    __ceph_caps_revoking_other(ci, cap, newcaps))
3453		    check_caps = 2;
3454
3455		cap->issued = newcaps;
3456		cap->implemented |= newcaps; /* add bits only, to
3457					      * avoid stepping on a
3458					      * pending revocation */
3459		wake = true;
3460	}
3461	BUG_ON(cap->issued & ~cap->implemented);
3462
3463	if (extra_info->inline_version > 0 &&
3464	    extra_info->inline_version >= ci->i_inline_version) {
3465		ci->i_inline_version = extra_info->inline_version;
3466		if (ci->i_inline_version != CEPH_INLINE_NONE &&
3467		    (newcaps & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)))
3468			fill_inline = true;
3469	}
3470
3471	if (ci->i_auth_cap == cap &&
3472	    le32_to_cpu(grant->op) == CEPH_CAP_OP_IMPORT) {
3473		if (newcaps & ~extra_info->issued)
3474			wake = true;
3475
3476		if (ci->i_requested_max_size > max_size ||
3477		    !(le32_to_cpu(grant->wanted) & CEPH_CAP_ANY_FILE_WR)) {
3478			/* re-request max_size if necessary */
3479			ci->i_requested_max_size = 0;
3480			wake = true;
3481		}
3482
3483		ceph_kick_flushing_inode_caps(session, ci);
3484		spin_unlock(&ci->i_ceph_lock);
3485		up_read(&session->s_mdsc->snap_rwsem);
3486	} else {
3487		spin_unlock(&ci->i_ceph_lock);
3488	}
3489
3490	if (fill_inline)
3491		ceph_fill_inline_data(inode, NULL, extra_info->inline_data,
3492				      extra_info->inline_len);
3493
3494	if (queue_trunc)
3495		ceph_queue_vmtruncate(inode);
3496
3497	if (writeback)
3498		/*
3499		 * queue inode for writeback: we can't actually call
3500		 * filemap_write_and_wait, etc. from message handler
3501		 * context.
3502		 */
3503		ceph_queue_writeback(inode);
3504	if (queue_invalidate)
3505		ceph_queue_invalidate(inode);
3506	if (deleted_inode)
3507		invalidate_aliases(inode);
3508	if (wake)
3509		wake_up_all(&ci->i_cap_wq);
3510
3511	if (check_caps == 1)
3512		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY | CHECK_CAPS_NOINVAL,
3513				session);
3514	else if (check_caps == 2)
3515		ceph_check_caps(ci, CHECK_CAPS_NOINVAL, session);
3516	else
3517		mutex_unlock(&session->s_mutex);
3518}
3519
3520/*
3521 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
3522 * MDS has been safely committed.
3523 */
3524static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
3525				 struct ceph_mds_caps *m,
3526				 struct ceph_mds_session *session,
3527				 struct ceph_cap *cap)
3528	__releases(ci->i_ceph_lock)
3529{
3530	struct ceph_inode_info *ci = ceph_inode(inode);
3531	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3532	struct ceph_cap_flush *cf, *tmp_cf;
3533	LIST_HEAD(to_remove);
3534	unsigned seq = le32_to_cpu(m->seq);
3535	int dirty = le32_to_cpu(m->dirty);
3536	int cleaned = 0;
3537	bool drop = false;
3538	bool wake_ci = false;
3539	bool wake_mdsc = false;
3540
3541	list_for_each_entry_safe(cf, tmp_cf, &ci->i_cap_flush_list, i_list) {
3542		/* Is this the one that was flushed? */
3543		if (cf->tid == flush_tid)
3544			cleaned = cf->caps;
3545
3546		/* Is this a capsnap? */
3547		if (cf->caps == 0)
3548			continue;
3549
3550		if (cf->tid <= flush_tid) {
3551			/*
3552			 * An earlier or current tid. The FLUSH_ACK should
3553			 * represent a superset of this flush's caps.
3554			 */
3555			wake_ci |= __detach_cap_flush_from_ci(ci, cf);
3556			list_add_tail(&cf->i_list, &to_remove);
3557		} else {
3558			/*
3559			 * This is a later one. Any caps in it are still dirty
3560			 * so don't count them as cleaned.
3561			 */
3562			cleaned &= ~cf->caps;
3563			if (!cleaned)
3564				break;
3565		}
3566	}
3567
3568	dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
3569	     " flushing %s -> %s\n",
3570	     inode, session->s_mds, seq, ceph_cap_string(dirty),
3571	     ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
3572	     ceph_cap_string(ci->i_flushing_caps & ~cleaned));
3573
3574	if (list_empty(&to_remove) && !cleaned)
3575		goto out;
3576
3577	ci->i_flushing_caps &= ~cleaned;
3578
3579	spin_lock(&mdsc->cap_dirty_lock);
3580
3581	list_for_each_entry(cf, &to_remove, i_list)
3582		wake_mdsc |= __detach_cap_flush_from_mdsc(mdsc, cf);
3583
3584	if (ci->i_flushing_caps == 0) {
3585		if (list_empty(&ci->i_cap_flush_list)) {
3586			list_del_init(&ci->i_flushing_item);
3587			if (!list_empty(&session->s_cap_flushing)) {
3588				dout(" mds%d still flushing cap on %p\n",
3589				     session->s_mds,
3590				     &list_first_entry(&session->s_cap_flushing,
3591						struct ceph_inode_info,
3592						i_flushing_item)->vfs_inode);
3593			}
3594		}
3595		mdsc->num_cap_flushing--;
 
3596		dout(" inode %p now !flushing\n", inode);
3597
3598		if (ci->i_dirty_caps == 0) {
3599			dout(" inode %p now clean\n", inode);
3600			BUG_ON(!list_empty(&ci->i_dirty_item));
3601			drop = true;
3602			if (ci->i_wr_ref == 0 &&
3603			    ci->i_wrbuffer_ref_head == 0) {
3604				BUG_ON(!ci->i_head_snapc);
3605				ceph_put_snap_context(ci->i_head_snapc);
3606				ci->i_head_snapc = NULL;
3607			}
3608		} else {
3609			BUG_ON(list_empty(&ci->i_dirty_item));
3610		}
3611	}
3612	spin_unlock(&mdsc->cap_dirty_lock);
 
3613
3614out:
3615	spin_unlock(&ci->i_ceph_lock);
3616
3617	while (!list_empty(&to_remove)) {
3618		cf = list_first_entry(&to_remove,
3619				      struct ceph_cap_flush, i_list);
3620		list_del(&cf->i_list);
3621		ceph_free_cap_flush(cf);
3622	}
3623
3624	if (wake_ci)
3625		wake_up_all(&ci->i_cap_wq);
3626	if (wake_mdsc)
3627		wake_up_all(&mdsc->cap_flushing_wq);
3628	if (drop)
3629		iput(inode);
3630}
3631
3632/*
3633 * Handle FLUSHSNAP_ACK.  MDS has flushed snap data to disk and we can
3634 * throw away our cap_snap.
3635 *
3636 * Caller hold s_mutex.
3637 */
3638static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
3639				     struct ceph_mds_caps *m,
3640				     struct ceph_mds_session *session)
3641{
3642	struct ceph_inode_info *ci = ceph_inode(inode);
3643	struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
3644	u64 follows = le64_to_cpu(m->snap_follows);
3645	struct ceph_cap_snap *capsnap;
3646	bool flushed = false;
3647	bool wake_ci = false;
3648	bool wake_mdsc = false;
3649
3650	dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
3651	     inode, ci, session->s_mds, follows);
3652
3653	spin_lock(&ci->i_ceph_lock);
3654	list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
3655		if (capsnap->follows == follows) {
3656			if (capsnap->cap_flush.tid != flush_tid) {
3657				dout(" cap_snap %p follows %lld tid %lld !="
3658				     " %lld\n", capsnap, follows,
3659				     flush_tid, capsnap->cap_flush.tid);
3660				break;
3661			}
3662			flushed = true;
 
 
 
 
 
 
 
3663			break;
3664		} else {
3665			dout(" skipping cap_snap %p follows %lld\n",
3666			     capsnap, capsnap->follows);
3667		}
3668	}
3669	if (flushed) {
3670		WARN_ON(capsnap->dirty_pages || capsnap->writing);
3671		dout(" removing %p cap_snap %p follows %lld\n",
3672		     inode, capsnap, follows);
3673		list_del(&capsnap->ci_item);
3674		wake_ci |= __detach_cap_flush_from_ci(ci, &capsnap->cap_flush);
3675
3676		spin_lock(&mdsc->cap_dirty_lock);
3677
3678		if (list_empty(&ci->i_cap_flush_list))
3679			list_del_init(&ci->i_flushing_item);
3680
3681		wake_mdsc |= __detach_cap_flush_from_mdsc(mdsc,
3682							  &capsnap->cap_flush);
3683		spin_unlock(&mdsc->cap_dirty_lock);
3684	}
3685	spin_unlock(&ci->i_ceph_lock);
3686	if (flushed) {
3687		ceph_put_snap_context(capsnap->context);
3688		ceph_put_cap_snap(capsnap);
3689		if (wake_ci)
3690			wake_up_all(&ci->i_cap_wq);
3691		if (wake_mdsc)
3692			wake_up_all(&mdsc->cap_flushing_wq);
3693		iput(inode);
3694	}
3695}
3696
3697/*
3698 * Handle TRUNC from MDS, indicating file truncation.
3699 *
3700 * caller hold s_mutex.
3701 */
3702static bool handle_cap_trunc(struct inode *inode,
3703			     struct ceph_mds_caps *trunc,
3704			     struct ceph_mds_session *session)
 
3705{
3706	struct ceph_inode_info *ci = ceph_inode(inode);
3707	int mds = session->s_mds;
3708	int seq = le32_to_cpu(trunc->seq);
3709	u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
3710	u64 truncate_size = le64_to_cpu(trunc->truncate_size);
3711	u64 size = le64_to_cpu(trunc->size);
3712	int implemented = 0;
3713	int dirty = __ceph_caps_dirty(ci);
3714	int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
3715	bool queue_trunc = false;
3716
3717	lockdep_assert_held(&ci->i_ceph_lock);
3718
3719	issued |= implemented | dirty;
3720
3721	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
3722	     inode, mds, seq, truncate_size, truncate_seq);
3723	queue_trunc = ceph_fill_file_size(inode, issued,
3724					  truncate_seq, truncate_size, size);
3725	return queue_trunc;
 
 
 
3726}
3727
3728/*
3729 * Handle EXPORT from MDS.  Cap is being migrated _from_ this mds to a
3730 * different one.  If we are the most recent migration we've seen (as
3731 * indicated by mseq), make note of the migrating cap bits for the
3732 * duration (until we see the corresponding IMPORT).
3733 *
3734 * caller holds s_mutex
3735 */
3736static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
3737			      struct ceph_mds_cap_peer *ph,
3738			      struct ceph_mds_session *session)
3739{
3740	struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
3741	struct ceph_mds_session *tsession = NULL;
3742	struct ceph_cap *cap, *tcap, *new_cap = NULL;
3743	struct ceph_inode_info *ci = ceph_inode(inode);
3744	u64 t_cap_id;
3745	unsigned mseq = le32_to_cpu(ex->migrate_seq);
3746	unsigned t_seq, t_mseq;
3747	int target, issued;
3748	int mds = session->s_mds;
3749
3750	if (ph) {
3751		t_cap_id = le64_to_cpu(ph->cap_id);
3752		t_seq = le32_to_cpu(ph->seq);
3753		t_mseq = le32_to_cpu(ph->mseq);
3754		target = le32_to_cpu(ph->mds);
3755	} else {
3756		t_cap_id = t_seq = t_mseq = 0;
3757		target = -1;
3758	}
3759
3760	dout("handle_cap_export inode %p ci %p mds%d mseq %d target %d\n",
3761	     inode, ci, mds, mseq, target);
3762retry:
3763	spin_lock(&ci->i_ceph_lock);
3764	cap = __get_cap_for_mds(ci, mds);
3765	if (!cap || cap->cap_id != le64_to_cpu(ex->cap_id))
3766		goto out_unlock;
3767
3768	if (target < 0) {
3769		__ceph_remove_cap(cap, false);
3770		goto out_unlock;
3771	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3772
3773	/*
3774	 * now we know we haven't received the cap import message yet
3775	 * because the exported cap still exist.
3776	 */
 
3777
3778	issued = cap->issued;
3779	if (issued != cap->implemented)
3780		pr_err_ratelimited("handle_cap_export: issued != implemented: "
3781				"ino (%llx.%llx) mds%d seq %d mseq %d "
3782				"issued %s implemented %s\n",
3783				ceph_vinop(inode), mds, cap->seq, cap->mseq,
3784				ceph_cap_string(issued),
3785				ceph_cap_string(cap->implemented));
3786
3787
3788	tcap = __get_cap_for_mds(ci, target);
3789	if (tcap) {
3790		/* already have caps from the target */
3791		if (tcap->cap_id == t_cap_id &&
3792		    ceph_seq_cmp(tcap->seq, t_seq) < 0) {
3793			dout(" updating import cap %p mds%d\n", tcap, target);
3794			tcap->cap_id = t_cap_id;
3795			tcap->seq = t_seq - 1;
3796			tcap->issue_seq = t_seq - 1;
3797			tcap->issued |= issued;
3798			tcap->implemented |= issued;
3799			if (cap == ci->i_auth_cap) {
3800				ci->i_auth_cap = tcap;
3801				change_auth_cap_ses(ci, tcap->session);
3802			}
3803		}
3804		__ceph_remove_cap(cap, false);
3805		goto out_unlock;
3806	} else if (tsession) {
3807		/* add placeholder for the export tagert */
3808		int flag = (cap == ci->i_auth_cap) ? CEPH_CAP_FLAG_AUTH : 0;
3809		tcap = new_cap;
3810		ceph_add_cap(inode, tsession, t_cap_id, issued, 0,
3811			     t_seq - 1, t_mseq, (u64)-1, flag, &new_cap);
3812
3813		if (!list_empty(&ci->i_cap_flush_list) &&
3814		    ci->i_auth_cap == tcap) {
3815			spin_lock(&mdsc->cap_dirty_lock);
3816			list_move_tail(&ci->i_flushing_item,
3817				       &tcap->session->s_cap_flushing);
3818			spin_unlock(&mdsc->cap_dirty_lock);
3819		}
3820
3821		__ceph_remove_cap(cap, false);
3822		goto out_unlock;
3823	}
 
3824
3825	spin_unlock(&ci->i_ceph_lock);
3826	mutex_unlock(&session->s_mutex);
3827
3828	/* open target session */
3829	tsession = ceph_mdsc_open_export_target_session(mdsc, target);
3830	if (!IS_ERR(tsession)) {
3831		if (mds > target) {
3832			mutex_lock(&session->s_mutex);
3833			mutex_lock_nested(&tsession->s_mutex,
3834					  SINGLE_DEPTH_NESTING);
3835		} else {
3836			mutex_lock(&tsession->s_mutex);
3837			mutex_lock_nested(&session->s_mutex,
3838					  SINGLE_DEPTH_NESTING);
3839		}
3840		new_cap = ceph_get_cap(mdsc, NULL);
3841	} else {
3842		WARN_ON(1);
3843		tsession = NULL;
3844		target = -1;
3845		mutex_lock(&session->s_mutex);
3846	}
3847	goto retry;
3848
3849out_unlock:
3850	spin_unlock(&ci->i_ceph_lock);
3851	mutex_unlock(&session->s_mutex);
3852	if (tsession) {
3853		mutex_unlock(&tsession->s_mutex);
3854		ceph_put_mds_session(tsession);
3855	}
3856	if (new_cap)
3857		ceph_put_cap(mdsc, new_cap);
3858}
3859
3860/*
3861 * Handle cap IMPORT.
 
3862 *
3863 * caller holds s_mutex. acquires i_ceph_lock
3864 */
3865static void handle_cap_import(struct ceph_mds_client *mdsc,
3866			      struct inode *inode, struct ceph_mds_caps *im,
3867			      struct ceph_mds_cap_peer *ph,
3868			      struct ceph_mds_session *session,
3869			      struct ceph_cap **target_cap, int *old_issued)
3870{
3871	struct ceph_inode_info *ci = ceph_inode(inode);
3872	struct ceph_cap *cap, *ocap, *new_cap = NULL;
3873	int mds = session->s_mds;
3874	int issued;
3875	unsigned caps = le32_to_cpu(im->caps);
3876	unsigned wanted = le32_to_cpu(im->wanted);
3877	unsigned seq = le32_to_cpu(im->seq);
3878	unsigned mseq = le32_to_cpu(im->migrate_seq);
3879	u64 realmino = le64_to_cpu(im->realm);
3880	u64 cap_id = le64_to_cpu(im->cap_id);
3881	u64 p_cap_id;
3882	int peer;
3883
3884	if (ph) {
3885		p_cap_id = le64_to_cpu(ph->cap_id);
3886		peer = le32_to_cpu(ph->mds);
3887	} else {
3888		p_cap_id = 0;
3889		peer = -1;
3890	}
 
 
3891
3892	dout("handle_cap_import inode %p ci %p mds%d mseq %d peer %d\n",
3893	     inode, ci, mds, mseq, peer);
3894retry:
3895	cap = __get_cap_for_mds(ci, mds);
3896	if (!cap) {
3897		if (!new_cap) {
3898			spin_unlock(&ci->i_ceph_lock);
3899			new_cap = ceph_get_cap(mdsc, NULL);
3900			spin_lock(&ci->i_ceph_lock);
3901			goto retry;
3902		}
3903		cap = new_cap;
3904	} else {
3905		if (new_cap) {
3906			ceph_put_cap(mdsc, new_cap);
3907			new_cap = NULL;
3908		}
3909	}
3910
3911	__ceph_caps_issued(ci, &issued);
3912	issued |= __ceph_caps_dirty(ci);
 
 
 
 
 
 
 
3913
3914	ceph_add_cap(inode, session, cap_id, caps, wanted, seq, mseq,
3915		     realmino, CEPH_CAP_FLAG_AUTH, &new_cap);
3916
3917	ocap = peer >= 0 ? __get_cap_for_mds(ci, peer) : NULL;
3918	if (ocap && ocap->cap_id == p_cap_id) {
3919		dout(" remove export cap %p mds%d flags %d\n",
3920		     ocap, peer, ph->flags);
3921		if ((ph->flags & CEPH_CAP_FLAG_AUTH) &&
3922		    (ocap->seq != le32_to_cpu(ph->seq) ||
3923		     ocap->mseq != le32_to_cpu(ph->mseq))) {
3924			pr_err_ratelimited("handle_cap_import: "
3925					"mismatched seq/mseq: ino (%llx.%llx) "
3926					"mds%d seq %d mseq %d importer mds%d "
3927					"has peer seq %d mseq %d\n",
3928					ceph_vinop(inode), peer, ocap->seq,
3929					ocap->mseq, mds, le32_to_cpu(ph->seq),
3930					le32_to_cpu(ph->mseq));
3931		}
3932		__ceph_remove_cap(ocap, (ph->flags & CEPH_CAP_FLAG_RELEASE));
3933	}
3934
3935	*old_issued = issued;
3936	*target_cap = cap;
3937}
3938
3939/*
3940 * Handle a caps message from the MDS.
3941 *
3942 * Identify the appropriate session, inode, and call the right handler
3943 * based on the cap op.
3944 */
3945void ceph_handle_caps(struct ceph_mds_session *session,
3946		      struct ceph_msg *msg)
3947{
3948	struct ceph_mds_client *mdsc = session->s_mdsc;
 
3949	struct inode *inode;
3950	struct ceph_inode_info *ci;
3951	struct ceph_cap *cap;
3952	struct ceph_mds_caps *h;
3953	struct ceph_mds_cap_peer *peer = NULL;
3954	struct ceph_snap_realm *realm = NULL;
3955	int op;
3956	int msg_version = le16_to_cpu(msg->hdr.version);
3957	u32 seq, mseq;
3958	struct ceph_vino vino;
 
 
 
3959	void *snaptrace;
3960	size_t snaptrace_len;
3961	void *p, *end;
3962	struct cap_extra_info extra_info = {};
3963	bool queue_trunc;
3964
3965	dout("handle_caps from mds%d\n", session->s_mds);
3966
3967	/* decode */
3968	end = msg->front.iov_base + msg->front.iov_len;
3969	if (msg->front.iov_len < sizeof(*h))
3970		goto bad;
3971	h = msg->front.iov_base;
3972	op = le32_to_cpu(h->op);
3973	vino.ino = le64_to_cpu(h->ino);
3974	vino.snap = CEPH_NOSNAP;
 
3975	seq = le32_to_cpu(h->seq);
3976	mseq = le32_to_cpu(h->migrate_seq);
 
 
3977
3978	snaptrace = h + 1;
3979	snaptrace_len = le32_to_cpu(h->snap_trace_len);
3980	p = snaptrace + snaptrace_len;
3981
3982	if (msg_version >= 2) {
3983		u32 flock_len;
 
 
 
3984		ceph_decode_32_safe(&p, end, flock_len, bad);
3985		if (p + flock_len > end)
3986			goto bad;
3987		p += flock_len;
3988	}
3989
3990	if (msg_version >= 3) {
3991		if (op == CEPH_CAP_OP_IMPORT) {
3992			if (p + sizeof(*peer) > end)
3993				goto bad;
3994			peer = p;
3995			p += sizeof(*peer);
3996		} else if (op == CEPH_CAP_OP_EXPORT) {
3997			/* recorded in unused fields */
3998			peer = (void *)&h->size;
3999		}
4000	}
4001
4002	if (msg_version >= 4) {
4003		ceph_decode_64_safe(&p, end, extra_info.inline_version, bad);
4004		ceph_decode_32_safe(&p, end, extra_info.inline_len, bad);
4005		if (p + extra_info.inline_len > end)
4006			goto bad;
4007		extra_info.inline_data = p;
4008		p += extra_info.inline_len;
4009	}
4010
4011	if (msg_version >= 5) {
4012		struct ceph_osd_client	*osdc = &mdsc->fsc->client->osdc;
4013		u32			epoch_barrier;
4014
4015		ceph_decode_32_safe(&p, end, epoch_barrier, bad);
4016		ceph_osdc_update_epoch_barrier(osdc, epoch_barrier);
4017	}
4018
4019	if (msg_version >= 8) {
4020		u64 flush_tid;
4021		u32 caller_uid, caller_gid;
4022		u32 pool_ns_len;
4023
4024		/* version >= 6 */
4025		ceph_decode_64_safe(&p, end, flush_tid, bad);
4026		/* version >= 7 */
4027		ceph_decode_32_safe(&p, end, caller_uid, bad);
4028		ceph_decode_32_safe(&p, end, caller_gid, bad);
4029		/* version >= 8 */
4030		ceph_decode_32_safe(&p, end, pool_ns_len, bad);
4031		if (pool_ns_len > 0) {
4032			ceph_decode_need(&p, end, pool_ns_len, bad);
4033			extra_info.pool_ns =
4034				ceph_find_or_create_string(p, pool_ns_len);
4035			p += pool_ns_len;
4036		}
4037	}
4038
4039	if (msg_version >= 9) {
4040		struct ceph_timespec *btime;
4041
4042		if (p + sizeof(*btime) > end)
4043			goto bad;
4044		btime = p;
4045		ceph_decode_timespec64(&extra_info.btime, btime);
4046		p += sizeof(*btime);
4047		ceph_decode_64_safe(&p, end, extra_info.change_attr, bad);
4048	}
4049
4050	if (msg_version >= 11) {
4051		u32 flags;
4052		/* version >= 10 */
4053		ceph_decode_32_safe(&p, end, flags, bad);
4054		/* version >= 11 */
4055		extra_info.dirstat_valid = true;
4056		ceph_decode_64_safe(&p, end, extra_info.nfiles, bad);
4057		ceph_decode_64_safe(&p, end, extra_info.nsubdirs, bad);
4058	}
4059
4060	/* lookup ino */
4061	inode = ceph_find_inode(mdsc->fsc->sb, vino);
4062	ci = ceph_inode(inode);
4063	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
4064	     vino.snap, inode);
4065
4066	mutex_lock(&session->s_mutex);
4067	session->s_seq++;
4068	dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
4069	     (unsigned)seq);
4070
 
 
 
 
 
4071	if (!inode) {
4072		dout(" i don't have ino %llx\n", vino.ino);
4073
4074		if (op == CEPH_CAP_OP_IMPORT) {
4075			cap = ceph_get_cap(mdsc, NULL);
4076			cap->cap_ino = vino.ino;
4077			cap->queue_release = 1;
4078			cap->cap_id = le64_to_cpu(h->cap_id);
4079			cap->mseq = mseq;
4080			cap->seq = seq;
4081			cap->issue_seq = seq;
4082			spin_lock(&session->s_cap_lock);
4083			__ceph_queue_cap_release(session, cap);
4084			spin_unlock(&session->s_cap_lock);
4085		}
4086		goto flush_cap_releases;
4087	}
4088
4089	/* these will work even if we don't have a cap yet */
4090	switch (op) {
4091	case CEPH_CAP_OP_FLUSHSNAP_ACK:
4092		handle_cap_flushsnap_ack(inode, le64_to_cpu(msg->hdr.tid),
4093					 h, session);
4094		goto done;
4095
4096	case CEPH_CAP_OP_EXPORT:
4097		handle_cap_export(inode, h, peer, session);
4098		goto done_unlocked;
4099
4100	case CEPH_CAP_OP_IMPORT:
4101		realm = NULL;
4102		if (snaptrace_len) {
4103			down_write(&mdsc->snap_rwsem);
4104			ceph_update_snap_trace(mdsc, snaptrace,
4105					       snaptrace + snaptrace_len,
4106					       false, &realm);
4107			downgrade_write(&mdsc->snap_rwsem);
4108		} else {
4109			down_read(&mdsc->snap_rwsem);
4110		}
4111		spin_lock(&ci->i_ceph_lock);
4112		handle_cap_import(mdsc, inode, h, peer, session,
4113				  &cap, &extra_info.issued);
4114		handle_cap_grant(inode, session, cap,
4115				 h, msg->middle, &extra_info);
4116		if (realm)
4117			ceph_put_snap_realm(mdsc, realm);
4118		goto done_unlocked;
4119	}
4120
4121	/* the rest require a cap */
4122	spin_lock(&ci->i_ceph_lock);
4123	cap = __get_cap_for_mds(ceph_inode(inode), session->s_mds);
4124	if (!cap) {
4125		dout(" no cap on %p ino %llx.%llx from mds%d\n",
4126		     inode, ceph_ino(inode), ceph_snap(inode),
4127		     session->s_mds);
4128		spin_unlock(&ci->i_ceph_lock);
4129		goto flush_cap_releases;
4130	}
4131
4132	/* note that each of these drops i_ceph_lock for us */
4133	switch (op) {
4134	case CEPH_CAP_OP_REVOKE:
4135	case CEPH_CAP_OP_GRANT:
4136		__ceph_caps_issued(ci, &extra_info.issued);
4137		extra_info.issued |= __ceph_caps_dirty(ci);
4138		handle_cap_grant(inode, session, cap,
4139				 h, msg->middle, &extra_info);
4140		goto done_unlocked;
4141
4142	case CEPH_CAP_OP_FLUSH_ACK:
4143		handle_cap_flush_ack(inode, le64_to_cpu(msg->hdr.tid),
4144				     h, session, cap);
4145		break;
4146
4147	case CEPH_CAP_OP_TRUNC:
4148		queue_trunc = handle_cap_trunc(inode, h, session);
4149		spin_unlock(&ci->i_ceph_lock);
4150		if (queue_trunc)
4151			ceph_queue_vmtruncate(inode);
4152		break;
4153
4154	default:
4155		spin_unlock(&ci->i_ceph_lock);
4156		pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
4157		       ceph_cap_op_name(op));
4158	}
4159
4160done:
4161	mutex_unlock(&session->s_mutex);
4162done_unlocked:
4163	ceph_put_string(extra_info.pool_ns);
4164	/* avoid calling iput_final() in mds dispatch threads */
4165	ceph_async_iput(inode);
4166	return;
4167
4168flush_cap_releases:
4169	/*
4170	 * send any cap release message to try to move things
4171	 * along for the mds (who clearly thinks we still have this
4172	 * cap).
4173	 */
4174	ceph_flush_cap_releases(mdsc, session);
4175	goto done;
 
 
 
 
 
 
 
 
 
4176
4177bad:
4178	pr_err("ceph_handle_caps: corrupt message\n");
4179	ceph_msg_dump(msg);
4180	return;
4181}
4182
4183/*
4184 * Delayed work handler to process end of delayed cap release LRU list.
4185 */
4186void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
4187{
4188	struct inode *inode;
4189	struct ceph_inode_info *ci;
 
4190
4191	dout("check_delayed_caps\n");
4192	spin_lock(&mdsc->cap_delay_lock);
4193	while (!list_empty(&mdsc->cap_delay_list)) {
 
 
4194		ci = list_first_entry(&mdsc->cap_delay_list,
4195				      struct ceph_inode_info,
4196				      i_cap_delay_list);
4197		if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
4198		    time_before(jiffies, ci->i_hold_caps_max))
4199			break;
4200		list_del_init(&ci->i_cap_delay_list);
4201
4202		inode = igrab(&ci->vfs_inode);
4203		if (inode) {
4204			spin_unlock(&mdsc->cap_delay_lock);
4205			dout("check_delayed_caps on %p\n", inode);
4206			ceph_check_caps(ci, 0, NULL);
4207			/* avoid calling iput_final() in tick thread */
4208			ceph_async_iput(inode);
4209			spin_lock(&mdsc->cap_delay_lock);
4210		}
4211	}
4212	spin_unlock(&mdsc->cap_delay_lock);
4213}
4214
4215/*
4216 * Flush all dirty caps to the mds
4217 */
4218static void flush_dirty_session_caps(struct ceph_mds_session *s)
4219{
4220	struct ceph_mds_client *mdsc = s->s_mdsc;
4221	struct ceph_inode_info *ci;
4222	struct inode *inode;
4223
4224	dout("flush_dirty_caps\n");
4225	spin_lock(&mdsc->cap_dirty_lock);
4226	while (!list_empty(&s->s_cap_dirty)) {
4227		ci = list_first_entry(&s->s_cap_dirty, struct ceph_inode_info,
4228				      i_dirty_item);
4229		inode = &ci->vfs_inode;
4230		ihold(inode);
4231		dout("flush_dirty_caps %p\n", inode);
4232		spin_unlock(&mdsc->cap_dirty_lock);
4233		ceph_check_caps(ci, CHECK_CAPS_FLUSH, NULL);
4234		iput(inode);
4235		spin_lock(&mdsc->cap_dirty_lock);
4236	}
4237	spin_unlock(&mdsc->cap_dirty_lock);
4238	dout("flush_dirty_caps done\n");
4239}
4240
4241static void iterate_sessions(struct ceph_mds_client *mdsc,
4242			     void (*cb)(struct ceph_mds_session *))
4243{
4244	int mds;
4245
4246	mutex_lock(&mdsc->mutex);
4247	for (mds = 0; mds < mdsc->max_sessions; ++mds) {
4248		struct ceph_mds_session *s;
4249
4250		if (!mdsc->sessions[mds])
4251			continue;
4252
4253		s = ceph_get_mds_session(mdsc->sessions[mds]);
4254		if (!s)
4255			continue;
4256
4257		mutex_unlock(&mdsc->mutex);
4258		cb(s);
4259		ceph_put_mds_session(s);
4260		mutex_lock(&mdsc->mutex);
4261	}
4262	mutex_unlock(&mdsc->mutex);
4263}
4264
4265void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
4266{
4267	iterate_sessions(mdsc, flush_dirty_session_caps);
4268}
4269
4270void __ceph_touch_fmode(struct ceph_inode_info *ci,
4271			struct ceph_mds_client *mdsc, int fmode)
4272{
4273	unsigned long now = jiffies;
4274	if (fmode & CEPH_FILE_MODE_RD)
4275		ci->i_last_rd = now;
4276	if (fmode & CEPH_FILE_MODE_WR)
4277		ci->i_last_wr = now;
4278	/* queue periodic check */
4279	if (fmode &&
4280	    __ceph_is_any_real_caps(ci) &&
4281	    list_empty(&ci->i_cap_delay_list))
4282		__cap_delay_requeue(mdsc, ci);
4283}
4284
4285void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count)
4286{
4287	int i;
4288	int bits = (fmode << 1) | 1;
4289	spin_lock(&ci->i_ceph_lock);
4290	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4291		if (bits & (1 << i))
4292			ci->i_nr_by_mode[i] += count;
4293	}
4294	spin_unlock(&ci->i_ceph_lock);
4295}
4296
4297/*
4298 * Drop open file reference.  If we were the last open file,
4299 * we may need to release capabilities to the MDS (or schedule
4300 * their delayed release).
4301 */
4302void ceph_put_fmode(struct ceph_inode_info *ci, int fmode, int count)
4303{
4304	int i;
4305	int bits = (fmode << 1) | 1;
 
4306	spin_lock(&ci->i_ceph_lock);
4307	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
4308		if (bits & (1 << i)) {
4309			BUG_ON(ci->i_nr_by_mode[i] < count);
4310			ci->i_nr_by_mode[i] -= count;
4311		}
4312	}
4313	spin_unlock(&ci->i_ceph_lock);
4314}
4315
4316/*
4317 * For a soon-to-be unlinked file, drop the LINK caps. If it
4318 * looks like the link count will hit 0, drop any other caps (other
4319 * than PIN) we don't specifically want (due to the file still being
4320 * open).
4321 */
4322int ceph_drop_caps_for_unlink(struct inode *inode)
4323{
4324	struct ceph_inode_info *ci = ceph_inode(inode);
4325	int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
4326
4327	spin_lock(&ci->i_ceph_lock);
4328	if (inode->i_nlink == 1) {
4329		drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
4330
4331		if (__ceph_caps_dirty(ci)) {
4332			struct ceph_mds_client *mdsc =
4333				ceph_inode_to_client(inode)->mdsc;
4334			__cap_delay_requeue_front(mdsc, ci);
4335		}
4336	}
4337	spin_unlock(&ci->i_ceph_lock);
4338	return drop;
4339}
4340
4341/*
4342 * Helpers for embedding cap and dentry lease releases into mds
4343 * requests.
4344 *
4345 * @force is used by dentry_release (below) to force inclusion of a
4346 * record for the directory inode, even when there aren't any caps to
4347 * drop.
4348 */
4349int ceph_encode_inode_release(void **p, struct inode *inode,
4350			      int mds, int drop, int unless, int force)
4351{
4352	struct ceph_inode_info *ci = ceph_inode(inode);
4353	struct ceph_cap *cap;
4354	struct ceph_mds_request_release *rel = *p;
4355	int used, dirty;
4356	int ret = 0;
4357
4358	spin_lock(&ci->i_ceph_lock);
4359	used = __ceph_caps_used(ci);
4360	dirty = __ceph_caps_dirty(ci);
4361
4362	dout("encode_inode_release %p mds%d used|dirty %s drop %s unless %s\n",
4363	     inode, mds, ceph_cap_string(used|dirty), ceph_cap_string(drop),
4364	     ceph_cap_string(unless));
4365
4366	/* only drop unused, clean caps */
4367	drop &= ~(used | dirty);
4368
4369	cap = __get_cap_for_mds(ci, mds);
4370	if (cap && __cap_is_valid(cap)) {
4371		unless &= cap->issued;
4372		if (unless) {
4373			if (unless & CEPH_CAP_AUTH_EXCL)
4374				drop &= ~CEPH_CAP_AUTH_SHARED;
4375			if (unless & CEPH_CAP_LINK_EXCL)
4376				drop &= ~CEPH_CAP_LINK_SHARED;
4377			if (unless & CEPH_CAP_XATTR_EXCL)
4378				drop &= ~CEPH_CAP_XATTR_SHARED;
4379			if (unless & CEPH_CAP_FILE_EXCL)
4380				drop &= ~CEPH_CAP_FILE_SHARED;
4381		}
4382
4383		if (force || (cap->issued & drop)) {
4384			if (cap->issued & drop) {
4385				int wanted = __ceph_caps_wanted(ci);
4386				dout("encode_inode_release %p cap %p "
4387				     "%s -> %s, wanted %s -> %s\n", inode, cap,
4388				     ceph_cap_string(cap->issued),
4389				     ceph_cap_string(cap->issued & ~drop),
4390				     ceph_cap_string(cap->mds_wanted),
4391				     ceph_cap_string(wanted));
4392
4393				cap->issued &= ~drop;
4394				cap->implemented &= ~drop;
4395				cap->mds_wanted = wanted;
4396				if (cap == ci->i_auth_cap &&
4397				    !(wanted & CEPH_CAP_ANY_FILE_WR))
4398					ci->i_requested_max_size = 0;
 
 
 
 
 
4399			} else {
4400				dout("encode_inode_release %p cap %p %s"
4401				     " (force)\n", inode, cap,
4402				     ceph_cap_string(cap->issued));
4403			}
4404
4405			rel->ino = cpu_to_le64(ceph_ino(inode));
4406			rel->cap_id = cpu_to_le64(cap->cap_id);
4407			rel->seq = cpu_to_le32(cap->seq);
4408			rel->issue_seq = cpu_to_le32(cap->issue_seq);
4409			rel->mseq = cpu_to_le32(cap->mseq);
4410			rel->caps = cpu_to_le32(cap->implemented);
4411			rel->wanted = cpu_to_le32(cap->mds_wanted);
4412			rel->dname_len = 0;
4413			rel->dname_seq = 0;
4414			*p += sizeof(*rel);
4415			ret = 1;
4416		} else {
4417			dout("encode_inode_release %p cap %p %s (noop)\n",
4418			     inode, cap, ceph_cap_string(cap->issued));
4419		}
4420	}
4421	spin_unlock(&ci->i_ceph_lock);
4422	return ret;
4423}
4424
4425int ceph_encode_dentry_release(void **p, struct dentry *dentry,
4426			       struct inode *dir,
4427			       int mds, int drop, int unless)
4428{
4429	struct dentry *parent = NULL;
4430	struct ceph_mds_request_release *rel = *p;
4431	struct ceph_dentry_info *di = ceph_dentry(dentry);
4432	int force = 0;
4433	int ret;
4434
4435	/*
4436	 * force an record for the directory caps if we have a dentry lease.
4437	 * this is racy (can't take i_ceph_lock and d_lock together), but it
4438	 * doesn't have to be perfect; the mds will revoke anything we don't
4439	 * release.
4440	 */
4441	spin_lock(&dentry->d_lock);
4442	if (di->lease_session && di->lease_session->s_mds == mds)
4443		force = 1;
4444	if (!dir) {
4445		parent = dget(dentry->d_parent);
4446		dir = d_inode(parent);
4447	}
4448	spin_unlock(&dentry->d_lock);
4449
4450	ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
4451	dput(parent);
4452
4453	spin_lock(&dentry->d_lock);
4454	if (ret && di->lease_session && di->lease_session->s_mds == mds) {
4455		dout("encode_dentry_release %p mds%d seq %d\n",
4456		     dentry, mds, (int)di->lease_seq);
4457		rel->dname_len = cpu_to_le32(dentry->d_name.len);
4458		memcpy(*p, dentry->d_name.name, dentry->d_name.len);
4459		*p += dentry->d_name.len;
4460		rel->dname_seq = cpu_to_le32(di->lease_seq);
4461		__ceph_mdsc_drop_dentry_lease(dentry);
4462	}
4463	spin_unlock(&dentry->d_lock);
4464	return ret;
4465}