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