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ceph: clean up cap release loop vs spinlock
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1#include "ceph_debug.h"
2
3#include <linux/fs.h>
4#include <linux/kernel.h>
5#include <linux/sched.h>
5a0e3ad6 6#include <linux/slab.h>
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7#include <linux/vmalloc.h>
8#include <linux/wait.h>
f1a3d572 9#include <linux/writeback.h>
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10
11#include "super.h"
12#include "decode.h"
13#include "messenger.h"
14
15/*
16 * Capability management
17 *
18 * The Ceph metadata servers control client access to inode metadata
19 * and file data by issuing capabilities, granting clients permission
20 * to read and/or write both inode field and file data to OSDs
21 * (storage nodes). Each capability consists of a set of bits
22 * indicating which operations are allowed.
23 *
24 * If the client holds a *_SHARED cap, the client has a coherent value
25 * that can be safely read from the cached inode.
26 *
27 * In the case of a *_EXCL (exclusive) or FILE_WR capabilities, the
28 * client is allowed to change inode attributes (e.g., file size,
29 * mtime), note its dirty state in the ceph_cap, and asynchronously
30 * flush that metadata change to the MDS.
31 *
32 * In the event of a conflicting operation (perhaps by another
33 * client), the MDS will revoke the conflicting client capabilities.
34 *
35 * In order for a client to cache an inode, it must hold a capability
36 * with at least one MDS server. When inodes are released, release
37 * notifications are batched and periodically sent en masse to the MDS
38 * cluster to release server state.
39 */
40
41
42/*
43 * Generate readable cap strings for debugging output.
44 */
45#define MAX_CAP_STR 20
46static char cap_str[MAX_CAP_STR][40];
47static DEFINE_SPINLOCK(cap_str_lock);
48static int last_cap_str;
49
50static char *gcap_string(char *s, int c)
51{
52 if (c & CEPH_CAP_GSHARED)
53 *s++ = 's';
54 if (c & CEPH_CAP_GEXCL)
55 *s++ = 'x';
56 if (c & CEPH_CAP_GCACHE)
57 *s++ = 'c';
58 if (c & CEPH_CAP_GRD)
59 *s++ = 'r';
60 if (c & CEPH_CAP_GWR)
61 *s++ = 'w';
62 if (c & CEPH_CAP_GBUFFER)
63 *s++ = 'b';
64 if (c & CEPH_CAP_GLAZYIO)
65 *s++ = 'l';
66 return s;
67}
68
69const char *ceph_cap_string(int caps)
70{
71 int i;
72 char *s;
73 int c;
74
75 spin_lock(&cap_str_lock);
76 i = last_cap_str++;
77 if (last_cap_str == MAX_CAP_STR)
78 last_cap_str = 0;
79 spin_unlock(&cap_str_lock);
80
81 s = cap_str[i];
82
83 if (caps & CEPH_CAP_PIN)
84 *s++ = 'p';
85
86 c = (caps >> CEPH_CAP_SAUTH) & 3;
87 if (c) {
88 *s++ = 'A';
89 s = gcap_string(s, c);
90 }
91
92 c = (caps >> CEPH_CAP_SLINK) & 3;
93 if (c) {
94 *s++ = 'L';
95 s = gcap_string(s, c);
96 }
97
98 c = (caps >> CEPH_CAP_SXATTR) & 3;
99 if (c) {
100 *s++ = 'X';
101 s = gcap_string(s, c);
102 }
103
104 c = caps >> CEPH_CAP_SFILE;
105 if (c) {
106 *s++ = 'F';
107 s = gcap_string(s, c);
108 }
109
110 if (s == cap_str[i])
111 *s++ = '-';
112 *s = 0;
113 return cap_str[i];
114}
115
116/*
117 * Cap reservations
118 *
119 * Maintain a global pool of preallocated struct ceph_caps, referenced
120 * by struct ceph_caps_reservations. This ensures that we preallocate
121 * memory needed to successfully process an MDS response. (If an MDS
122 * sends us cap information and we fail to process it, we will have
123 * problems due to the client and MDS being out of sync.)
124 *
125 * Reservations are 'owned' by a ceph_cap_reservation context.
126 */
127static spinlock_t caps_list_lock;
128static struct list_head caps_list; /* unused (reserved or unreserved) */
129static int caps_total_count; /* total caps allocated */
130static int caps_use_count; /* in use */
131static int caps_reserve_count; /* unused, reserved */
132static int caps_avail_count; /* unused, unreserved */
85ccce43 133static int caps_min_count; /* keep at least this many (unreserved) */
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134
135void __init ceph_caps_init(void)
136{
137 INIT_LIST_HEAD(&caps_list);
138 spin_lock_init(&caps_list_lock);
139}
140
141void ceph_caps_finalize(void)
142{
143 struct ceph_cap *cap;
144
145 spin_lock(&caps_list_lock);
146 while (!list_empty(&caps_list)) {
147 cap = list_first_entry(&caps_list, struct ceph_cap, caps_item);
148 list_del(&cap->caps_item);
149 kmem_cache_free(ceph_cap_cachep, cap);
150 }
151 caps_total_count = 0;
152 caps_avail_count = 0;
153 caps_use_count = 0;
154 caps_reserve_count = 0;
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155 caps_min_count = 0;
156 spin_unlock(&caps_list_lock);
157}
158
159void ceph_adjust_min_caps(int delta)
160{
161 spin_lock(&caps_list_lock);
162 caps_min_count += delta;
163 BUG_ON(caps_min_count < 0);
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164 spin_unlock(&caps_list_lock);
165}
166
167int ceph_reserve_caps(struct ceph_cap_reservation *ctx, int need)
168{
169 int i;
170 struct ceph_cap *cap;
171 int have;
172 int alloc = 0;
173 LIST_HEAD(newcaps);
174 int ret = 0;
175
176 dout("reserve caps ctx=%p need=%d\n", ctx, need);
177
178 /* first reserve any caps that are already allocated */
179 spin_lock(&caps_list_lock);
180 if (caps_avail_count >= need)
181 have = need;
182 else
183 have = caps_avail_count;
184 caps_avail_count -= have;
185 caps_reserve_count += have;
186 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count +
187 caps_avail_count);
188 spin_unlock(&caps_list_lock);
189
190 for (i = have; i < need; i++) {
191 cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
192 if (!cap) {
193 ret = -ENOMEM;
194 goto out_alloc_count;
195 }
196 list_add(&cap->caps_item, &newcaps);
197 alloc++;
198 }
199 BUG_ON(have + alloc != need);
200
201 spin_lock(&caps_list_lock);
202 caps_total_count += alloc;
203 caps_reserve_count += alloc;
204 list_splice(&newcaps, &caps_list);
205
206 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count +
207 caps_avail_count);
208 spin_unlock(&caps_list_lock);
209
210 ctx->count = need;
211 dout("reserve caps ctx=%p %d = %d used + %d resv + %d avail\n",
212 ctx, caps_total_count, caps_use_count, caps_reserve_count,
213 caps_avail_count);
214 return 0;
215
216out_alloc_count:
217 /* we didn't manage to reserve as much as we needed */
218 pr_warning("reserve caps ctx=%p ENOMEM need=%d got=%d\n",
219 ctx, need, have);
220 return ret;
221}
222
223int ceph_unreserve_caps(struct ceph_cap_reservation *ctx)
224{
225 dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
226 if (ctx->count) {
227 spin_lock(&caps_list_lock);
228 BUG_ON(caps_reserve_count < ctx->count);
229 caps_reserve_count -= ctx->count;
230 caps_avail_count += ctx->count;
231 ctx->count = 0;
232 dout("unreserve caps %d = %d used + %d resv + %d avail\n",
233 caps_total_count, caps_use_count, caps_reserve_count,
234 caps_avail_count);
235 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count +
236 caps_avail_count);
237 spin_unlock(&caps_list_lock);
238 }
239 return 0;
240}
241
242static struct ceph_cap *get_cap(struct ceph_cap_reservation *ctx)
243{
244 struct ceph_cap *cap = NULL;
245
246 /* temporary, until we do something about cap import/export */
247 if (!ctx)
248 return kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS);
249
250 spin_lock(&caps_list_lock);
251 dout("get_cap ctx=%p (%d) %d = %d used + %d resv + %d avail\n",
252 ctx, ctx->count, caps_total_count, caps_use_count,
253 caps_reserve_count, caps_avail_count);
254 BUG_ON(!ctx->count);
255 BUG_ON(ctx->count > caps_reserve_count);
256 BUG_ON(list_empty(&caps_list));
257
258 ctx->count--;
259 caps_reserve_count--;
260 caps_use_count++;
261
262 cap = list_first_entry(&caps_list, struct ceph_cap, caps_item);
263 list_del(&cap->caps_item);
264
265 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count +
266 caps_avail_count);
267 spin_unlock(&caps_list_lock);
268 return cap;
269}
270
7c1332b8 271void ceph_put_cap(struct ceph_cap *cap)
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272{
273 spin_lock(&caps_list_lock);
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274 dout("put_cap %p %d = %d used + %d resv + %d avail\n",
275 cap, caps_total_count, caps_use_count,
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276 caps_reserve_count, caps_avail_count);
277 caps_use_count--;
278 /*
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279 * Keep some preallocated caps around (ceph_min_count), to
280 * avoid lots of free/alloc churn.
a8599bd8 281 */
85ccce43 282 if (caps_avail_count >= caps_reserve_count + caps_min_count) {
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283 caps_total_count--;
284 kmem_cache_free(ceph_cap_cachep, cap);
285 } else {
7c1332b8 286 caps_avail_count++;
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287 list_add(&cap->caps_item, &caps_list);
288 }
289
290 BUG_ON(caps_total_count != caps_use_count + caps_reserve_count +
291 caps_avail_count);
292 spin_unlock(&caps_list_lock);
293}
294
295void ceph_reservation_status(struct ceph_client *client,
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296 int *total, int *avail, int *used, int *reserved,
297 int *min)
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298{
299 if (total)
300 *total = caps_total_count;
301 if (avail)
302 *avail = caps_avail_count;
303 if (used)
304 *used = caps_use_count;
305 if (reserved)
306 *reserved = caps_reserve_count;
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307 if (min)
308 *min = caps_min_count;
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309}
310
311/*
312 * Find ceph_cap for given mds, if any.
313 *
314 * Called with i_lock held.
315 */
316static struct ceph_cap *__get_cap_for_mds(struct ceph_inode_info *ci, int mds)
317{
318 struct ceph_cap *cap;
319 struct rb_node *n = ci->i_caps.rb_node;
320
321 while (n) {
322 cap = rb_entry(n, struct ceph_cap, ci_node);
323 if (mds < cap->mds)
324 n = n->rb_left;
325 else if (mds > cap->mds)
326 n = n->rb_right;
327 else
328 return cap;
329 }
330 return NULL;
331}
332
333/*
334 * Return id of any MDS with a cap, preferably FILE_WR|WRBUFFER|EXCL, else
335 * -1.
336 */
337static int __ceph_get_cap_mds(struct ceph_inode_info *ci, u32 *mseq)
338{
339 struct ceph_cap *cap;
340 int mds = -1;
341 struct rb_node *p;
342
343 /* prefer mds with WR|WRBUFFER|EXCL caps */
344 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
345 cap = rb_entry(p, struct ceph_cap, ci_node);
346 mds = cap->mds;
347 if (mseq)
348 *mseq = cap->mseq;
349 if (cap->issued & (CEPH_CAP_FILE_WR |
350 CEPH_CAP_FILE_BUFFER |
351 CEPH_CAP_FILE_EXCL))
352 break;
353 }
354 return mds;
355}
356
357int ceph_get_cap_mds(struct inode *inode)
358{
359 int mds;
360 spin_lock(&inode->i_lock);
361 mds = __ceph_get_cap_mds(ceph_inode(inode), NULL);
362 spin_unlock(&inode->i_lock);
363 return mds;
364}
365
366/*
367 * Called under i_lock.
368 */
369static void __insert_cap_node(struct ceph_inode_info *ci,
370 struct ceph_cap *new)
371{
372 struct rb_node **p = &ci->i_caps.rb_node;
373 struct rb_node *parent = NULL;
374 struct ceph_cap *cap = NULL;
375
376 while (*p) {
377 parent = *p;
378 cap = rb_entry(parent, struct ceph_cap, ci_node);
379 if (new->mds < cap->mds)
380 p = &(*p)->rb_left;
381 else if (new->mds > cap->mds)
382 p = &(*p)->rb_right;
383 else
384 BUG();
385 }
386
387 rb_link_node(&new->ci_node, parent, p);
388 rb_insert_color(&new->ci_node, &ci->i_caps);
389}
390
391/*
392 * (re)set cap hold timeouts, which control the delayed release
393 * of unused caps back to the MDS. Should be called on cap use.
394 */
395static void __cap_set_timeouts(struct ceph_mds_client *mdsc,
396 struct ceph_inode_info *ci)
397{
6b805185 398 struct ceph_mount_args *ma = mdsc->client->mount_args;
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399
400 ci->i_hold_caps_min = round_jiffies(jiffies +
401 ma->caps_wanted_delay_min * HZ);
402 ci->i_hold_caps_max = round_jiffies(jiffies +
403 ma->caps_wanted_delay_max * HZ);
404 dout("__cap_set_timeouts %p min %lu max %lu\n", &ci->vfs_inode,
405 ci->i_hold_caps_min - jiffies, ci->i_hold_caps_max - jiffies);
406}
407
408/*
409 * (Re)queue cap at the end of the delayed cap release list.
410 *
411 * If I_FLUSH is set, leave the inode at the front of the list.
412 *
413 * Caller holds i_lock
414 * -> we take mdsc->cap_delay_lock
415 */
416static void __cap_delay_requeue(struct ceph_mds_client *mdsc,
417 struct ceph_inode_info *ci)
418{
419 __cap_set_timeouts(mdsc, ci);
420 dout("__cap_delay_requeue %p flags %d at %lu\n", &ci->vfs_inode,
421 ci->i_ceph_flags, ci->i_hold_caps_max);
422 if (!mdsc->stopping) {
423 spin_lock(&mdsc->cap_delay_lock);
424 if (!list_empty(&ci->i_cap_delay_list)) {
425 if (ci->i_ceph_flags & CEPH_I_FLUSH)
426 goto no_change;
427 list_del_init(&ci->i_cap_delay_list);
428 }
429 list_add_tail(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
430no_change:
431 spin_unlock(&mdsc->cap_delay_lock);
432 }
433}
434
435/*
436 * Queue an inode for immediate writeback. Mark inode with I_FLUSH,
437 * indicating we should send a cap message to flush dirty metadata
438 * asap, and move to the front of the delayed cap list.
439 */
440static void __cap_delay_requeue_front(struct ceph_mds_client *mdsc,
441 struct ceph_inode_info *ci)
442{
443 dout("__cap_delay_requeue_front %p\n", &ci->vfs_inode);
444 spin_lock(&mdsc->cap_delay_lock);
445 ci->i_ceph_flags |= CEPH_I_FLUSH;
446 if (!list_empty(&ci->i_cap_delay_list))
447 list_del_init(&ci->i_cap_delay_list);
448 list_add(&ci->i_cap_delay_list, &mdsc->cap_delay_list);
449 spin_unlock(&mdsc->cap_delay_lock);
450}
451
452/*
453 * Cancel delayed work on cap.
454 *
455 * Caller must hold i_lock.
456 */
457static void __cap_delay_cancel(struct ceph_mds_client *mdsc,
458 struct ceph_inode_info *ci)
459{
460 dout("__cap_delay_cancel %p\n", &ci->vfs_inode);
461 if (list_empty(&ci->i_cap_delay_list))
462 return;
463 spin_lock(&mdsc->cap_delay_lock);
464 list_del_init(&ci->i_cap_delay_list);
465 spin_unlock(&mdsc->cap_delay_lock);
466}
467
468/*
469 * Common issue checks for add_cap, handle_cap_grant.
470 */
471static void __check_cap_issue(struct ceph_inode_info *ci, struct ceph_cap *cap,
472 unsigned issued)
473{
474 unsigned had = __ceph_caps_issued(ci, NULL);
475
476 /*
477 * Each time we receive FILE_CACHE anew, we increment
478 * i_rdcache_gen.
479 */
480 if ((issued & CEPH_CAP_FILE_CACHE) &&
481 (had & CEPH_CAP_FILE_CACHE) == 0)
482 ci->i_rdcache_gen++;
483
484 /*
485 * if we are newly issued FILE_SHARED, clear I_COMPLETE; we
486 * don't know what happened to this directory while we didn't
487 * have the cap.
488 */
489 if ((issued & CEPH_CAP_FILE_SHARED) &&
490 (had & CEPH_CAP_FILE_SHARED) == 0) {
491 ci->i_shared_gen++;
492 if (S_ISDIR(ci->vfs_inode.i_mode)) {
493 dout(" marking %p NOT complete\n", &ci->vfs_inode);
494 ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
495 }
496 }
497}
498
499/*
500 * Add a capability under the given MDS session.
501 *
502 * Caller should hold session snap_rwsem (read) and s_mutex.
503 *
504 * @fmode is the open file mode, if we are opening a file, otherwise
505 * it is < 0. (This is so we can atomically add the cap and add an
506 * open file reference to it.)
507 */
508int ceph_add_cap(struct inode *inode,
509 struct ceph_mds_session *session, u64 cap_id,
510 int fmode, unsigned issued, unsigned wanted,
511 unsigned seq, unsigned mseq, u64 realmino, int flags,
512 struct ceph_cap_reservation *caps_reservation)
513{
514 struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc;
515 struct ceph_inode_info *ci = ceph_inode(inode);
516 struct ceph_cap *new_cap = NULL;
517 struct ceph_cap *cap;
518 int mds = session->s_mds;
519 int actual_wanted;
520
521 dout("add_cap %p mds%d cap %llx %s seq %d\n", inode,
522 session->s_mds, cap_id, ceph_cap_string(issued), seq);
523
524 /*
525 * If we are opening the file, include file mode wanted bits
526 * in wanted.
527 */
528 if (fmode >= 0)
529 wanted |= ceph_caps_for_mode(fmode);
530
531retry:
532 spin_lock(&inode->i_lock);
533 cap = __get_cap_for_mds(ci, mds);
534 if (!cap) {
535 if (new_cap) {
536 cap = new_cap;
537 new_cap = NULL;
538 } else {
539 spin_unlock(&inode->i_lock);
540 new_cap = get_cap(caps_reservation);
541 if (new_cap == NULL)
542 return -ENOMEM;
543 goto retry;
544 }
545
546 cap->issued = 0;
547 cap->implemented = 0;
548 cap->mds = mds;
549 cap->mds_wanted = 0;
550
551 cap->ci = ci;
552 __insert_cap_node(ci, cap);
553
554 /* clear out old exporting info? (i.e. on cap import) */
555 if (ci->i_cap_exporting_mds == mds) {
556 ci->i_cap_exporting_issued = 0;
557 ci->i_cap_exporting_mseq = 0;
558 ci->i_cap_exporting_mds = -1;
559 }
560
561 /* add to session cap list */
562 cap->session = session;
563 spin_lock(&session->s_cap_lock);
564 list_add_tail(&cap->session_caps, &session->s_caps);
565 session->s_nr_caps++;
566 spin_unlock(&session->s_cap_lock);
567 }
568
569 if (!ci->i_snap_realm) {
570 /*
571 * add this inode to the appropriate snap realm
572 */
573 struct ceph_snap_realm *realm = ceph_lookup_snap_realm(mdsc,
574 realmino);
575 if (realm) {
576 ceph_get_snap_realm(mdsc, realm);
577 spin_lock(&realm->inodes_with_caps_lock);
578 ci->i_snap_realm = realm;
579 list_add(&ci->i_snap_realm_item,
580 &realm->inodes_with_caps);
581 spin_unlock(&realm->inodes_with_caps_lock);
582 } else {
583 pr_err("ceph_add_cap: couldn't find snap realm %llx\n",
584 realmino);
585 }
586 }
587
588 __check_cap_issue(ci, cap, issued);
589
590 /*
591 * If we are issued caps we don't want, or the mds' wanted
592 * value appears to be off, queue a check so we'll release
593 * later and/or update the mds wanted value.
594 */
595 actual_wanted = __ceph_caps_wanted(ci);
596 if ((wanted & ~actual_wanted) ||
597 (issued & ~actual_wanted & CEPH_CAP_ANY_WR)) {
598 dout(" issued %s, mds wanted %s, actual %s, queueing\n",
599 ceph_cap_string(issued), ceph_cap_string(wanted),
600 ceph_cap_string(actual_wanted));
601 __cap_delay_requeue(mdsc, ci);
602 }
603
604 if (flags & CEPH_CAP_FLAG_AUTH)
605 ci->i_auth_cap = cap;
606 else if (ci->i_auth_cap == cap)
607 ci->i_auth_cap = NULL;
608
609 dout("add_cap inode %p (%llx.%llx) cap %p %s now %s seq %d mds%d\n",
610 inode, ceph_vinop(inode), cap, ceph_cap_string(issued),
611 ceph_cap_string(issued|cap->issued), seq, mds);
612 cap->cap_id = cap_id;
613 cap->issued = issued;
614 cap->implemented |= issued;
615 cap->mds_wanted |= wanted;
616 cap->seq = seq;
617 cap->issue_seq = seq;
618 cap->mseq = mseq;
685f9a5d 619 cap->cap_gen = session->s_cap_gen;
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620
621 if (fmode >= 0)
622 __ceph_get_fmode(ci, fmode);
623 spin_unlock(&inode->i_lock);
624 wake_up(&ci->i_cap_wq);
625 return 0;
626}
627
628/*
629 * Return true if cap has not timed out and belongs to the current
630 * generation of the MDS session (i.e. has not gone 'stale' due to
631 * us losing touch with the mds).
632 */
633static int __cap_is_valid(struct ceph_cap *cap)
634{
635 unsigned long ttl;
cdac8303 636 u32 gen;
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637
638 spin_lock(&cap->session->s_cap_lock);
639 gen = cap->session->s_cap_gen;
640 ttl = cap->session->s_cap_ttl;
641 spin_unlock(&cap->session->s_cap_lock);
642
685f9a5d 643 if (cap->cap_gen < gen || time_after_eq(jiffies, ttl)) {
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644 dout("__cap_is_valid %p cap %p issued %s "
645 "but STALE (gen %u vs %u)\n", &cap->ci->vfs_inode,
685f9a5d 646 cap, ceph_cap_string(cap->issued), cap->cap_gen, gen);
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647 return 0;
648 }
649
650 return 1;
651}
652
653/*
654 * Return set of valid cap bits issued to us. Note that caps time
655 * out, and may be invalidated in bulk if the client session times out
656 * and session->s_cap_gen is bumped.
657 */
658int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented)
659{
7af8f1e4 660 int have = ci->i_snap_caps | ci->i_cap_exporting_issued;
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661 struct ceph_cap *cap;
662 struct rb_node *p;
663
664 if (implemented)
665 *implemented = 0;
666 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
667 cap = rb_entry(p, struct ceph_cap, ci_node);
668 if (!__cap_is_valid(cap))
669 continue;
670 dout("__ceph_caps_issued %p cap %p issued %s\n",
671 &ci->vfs_inode, cap, ceph_cap_string(cap->issued));
672 have |= cap->issued;
673 if (implemented)
674 *implemented |= cap->implemented;
675 }
676 return have;
677}
678
679/*
680 * Get cap bits issued by caps other than @ocap
681 */
682int __ceph_caps_issued_other(struct ceph_inode_info *ci, struct ceph_cap *ocap)
683{
684 int have = ci->i_snap_caps;
685 struct ceph_cap *cap;
686 struct rb_node *p;
687
688 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
689 cap = rb_entry(p, struct ceph_cap, ci_node);
690 if (cap == ocap)
691 continue;
692 if (!__cap_is_valid(cap))
693 continue;
694 have |= cap->issued;
695 }
696 return have;
697}
698
699/*
700 * Move a cap to the end of the LRU (oldest caps at list head, newest
701 * at list tail).
702 */
703static void __touch_cap(struct ceph_cap *cap)
704{
705 struct ceph_mds_session *s = cap->session;
706
a8599bd8 707 spin_lock(&s->s_cap_lock);
7c1332b8 708 if (s->s_cap_iterator == NULL) {
5dacf091
SW
709 dout("__touch_cap %p cap %p mds%d\n", &cap->ci->vfs_inode, cap,
710 s->s_mds);
711 list_move_tail(&cap->session_caps, &s->s_caps);
712 } else {
713 dout("__touch_cap %p cap %p mds%d NOP, iterating over caps\n",
714 &cap->ci->vfs_inode, cap, s->s_mds);
715 }
a8599bd8
SW
716 spin_unlock(&s->s_cap_lock);
717}
718
719/*
720 * Check if we hold the given mask. If so, move the cap(s) to the
721 * front of their respective LRUs. (This is the preferred way for
722 * callers to check for caps they want.)
723 */
724int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
725{
726 struct ceph_cap *cap;
727 struct rb_node *p;
728 int have = ci->i_snap_caps;
729
730 if ((have & mask) == mask) {
731 dout("__ceph_caps_issued_mask %p snap issued %s"
732 " (mask %s)\n", &ci->vfs_inode,
733 ceph_cap_string(have),
734 ceph_cap_string(mask));
735 return 1;
736 }
737
738 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
739 cap = rb_entry(p, struct ceph_cap, ci_node);
740 if (!__cap_is_valid(cap))
741 continue;
742 if ((cap->issued & mask) == mask) {
743 dout("__ceph_caps_issued_mask %p cap %p issued %s"
744 " (mask %s)\n", &ci->vfs_inode, cap,
745 ceph_cap_string(cap->issued),
746 ceph_cap_string(mask));
747 if (touch)
748 __touch_cap(cap);
749 return 1;
750 }
751
752 /* does a combination of caps satisfy mask? */
753 have |= cap->issued;
754 if ((have & mask) == mask) {
755 dout("__ceph_caps_issued_mask %p combo issued %s"
756 " (mask %s)\n", &ci->vfs_inode,
757 ceph_cap_string(cap->issued),
758 ceph_cap_string(mask));
759 if (touch) {
760 struct rb_node *q;
761
762 /* touch this + preceeding caps */
763 __touch_cap(cap);
764 for (q = rb_first(&ci->i_caps); q != p;
765 q = rb_next(q)) {
766 cap = rb_entry(q, struct ceph_cap,
767 ci_node);
768 if (!__cap_is_valid(cap))
769 continue;
770 __touch_cap(cap);
771 }
772 }
773 return 1;
774 }
775 }
776
777 return 0;
778}
779
780/*
781 * Return true if mask caps are currently being revoked by an MDS.
782 */
783int ceph_caps_revoking(struct ceph_inode_info *ci, int mask)
784{
785 struct inode *inode = &ci->vfs_inode;
786 struct ceph_cap *cap;
787 struct rb_node *p;
788 int ret = 0;
789
790 spin_lock(&inode->i_lock);
791 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
792 cap = rb_entry(p, struct ceph_cap, ci_node);
793 if (__cap_is_valid(cap) &&
794 (cap->implemented & ~cap->issued & mask)) {
795 ret = 1;
796 break;
797 }
798 }
799 spin_unlock(&inode->i_lock);
800 dout("ceph_caps_revoking %p %s = %d\n", inode,
801 ceph_cap_string(mask), ret);
802 return ret;
803}
804
805int __ceph_caps_used(struct ceph_inode_info *ci)
806{
807 int used = 0;
808 if (ci->i_pin_ref)
809 used |= CEPH_CAP_PIN;
810 if (ci->i_rd_ref)
811 used |= CEPH_CAP_FILE_RD;
812 if (ci->i_rdcache_ref || ci->i_rdcache_gen)
813 used |= CEPH_CAP_FILE_CACHE;
814 if (ci->i_wr_ref)
815 used |= CEPH_CAP_FILE_WR;
816 if (ci->i_wrbuffer_ref)
817 used |= CEPH_CAP_FILE_BUFFER;
818 return used;
819}
820
821/*
822 * wanted, by virtue of open file modes
823 */
824int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
825{
826 int want = 0;
827 int mode;
828 for (mode = 0; mode < 4; mode++)
829 if (ci->i_nr_by_mode[mode])
830 want |= ceph_caps_for_mode(mode);
831 return want;
832}
833
834/*
835 * Return caps we have registered with the MDS(s) as 'wanted'.
836 */
837int __ceph_caps_mds_wanted(struct ceph_inode_info *ci)
838{
839 struct ceph_cap *cap;
840 struct rb_node *p;
841 int mds_wanted = 0;
842
843 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
844 cap = rb_entry(p, struct ceph_cap, ci_node);
845 if (!__cap_is_valid(cap))
846 continue;
847 mds_wanted |= cap->mds_wanted;
848 }
849 return mds_wanted;
850}
851
852/*
853 * called under i_lock
854 */
855static int __ceph_is_any_caps(struct ceph_inode_info *ci)
856{
857 return !RB_EMPTY_ROOT(&ci->i_caps) || ci->i_cap_exporting_mds >= 0;
858}
859
860/*
f818a736
SW
861 * Remove a cap. Take steps to deal with a racing iterate_session_caps.
862 *
a6369741
SW
863 * caller should hold i_lock.
864 * caller will not hold session s_mutex if called from destroy_inode.
a8599bd8 865 */
7c1332b8 866void __ceph_remove_cap(struct ceph_cap *cap)
a8599bd8
SW
867{
868 struct ceph_mds_session *session = cap->session;
869 struct ceph_inode_info *ci = cap->ci;
640ef79d
CR
870 struct ceph_mds_client *mdsc =
871 &ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
f818a736 872 int removed = 0;
a8599bd8
SW
873
874 dout("__ceph_remove_cap %p from %p\n", cap, &ci->vfs_inode);
875
7c1332b8
SW
876 /* remove from session list */
877 spin_lock(&session->s_cap_lock);
878 if (session->s_cap_iterator == cap) {
879 /* not yet, we are iterating over this very cap */
880 dout("__ceph_remove_cap delaying %p removal from session %p\n",
881 cap, cap->session);
882 } else {
883 list_del_init(&cap->session_caps);
884 session->s_nr_caps--;
885 cap->session = NULL;
f818a736 886 removed = 1;
7c1332b8 887 }
f818a736
SW
888 /* protect backpointer with s_cap_lock: see iterate_session_caps */
889 cap->ci = NULL;
7c1332b8
SW
890 spin_unlock(&session->s_cap_lock);
891
f818a736
SW
892 /* remove from inode list */
893 rb_erase(&cap->ci_node, &ci->i_caps);
894 if (ci->i_auth_cap == cap)
895 ci->i_auth_cap = NULL;
896
897 if (removed)
7c1332b8 898 ceph_put_cap(cap);
a8599bd8
SW
899
900 if (!__ceph_is_any_caps(ci) && ci->i_snap_realm) {
901 struct ceph_snap_realm *realm = ci->i_snap_realm;
902 spin_lock(&realm->inodes_with_caps_lock);
903 list_del_init(&ci->i_snap_realm_item);
904 ci->i_snap_realm_counter++;
905 ci->i_snap_realm = NULL;
906 spin_unlock(&realm->inodes_with_caps_lock);
907 ceph_put_snap_realm(mdsc, realm);
908 }
909 if (!__ceph_is_any_real_caps(ci))
910 __cap_delay_cancel(mdsc, ci);
911}
912
913/*
914 * Build and send a cap message to the given MDS.
915 *
916 * Caller should be holding s_mutex.
917 */
918static int send_cap_msg(struct ceph_mds_session *session,
919 u64 ino, u64 cid, int op,
920 int caps, int wanted, int dirty,
921 u32 seq, u64 flush_tid, u32 issue_seq, u32 mseq,
922 u64 size, u64 max_size,
923 struct timespec *mtime, struct timespec *atime,
924 u64 time_warp_seq,
925 uid_t uid, gid_t gid, mode_t mode,
926 u64 xattr_version,
927 struct ceph_buffer *xattrs_buf,
928 u64 follows)
929{
930 struct ceph_mds_caps *fc;
931 struct ceph_msg *msg;
932
933 dout("send_cap_msg %s %llx %llx caps %s wanted %s dirty %s"
934 " seq %u/%u mseq %u follows %lld size %llu/%llu"
935 " xattr_ver %llu xattr_len %d\n", ceph_cap_op_name(op),
936 cid, ino, ceph_cap_string(caps), ceph_cap_string(wanted),
937 ceph_cap_string(dirty),
938 seq, issue_seq, mseq, follows, size, max_size,
939 xattr_version, xattrs_buf ? (int)xattrs_buf->vec.iov_len : 0);
940
bb257664 941 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPS, sizeof(*fc));
a79832f2
SW
942 if (!msg)
943 return -ENOMEM;
a8599bd8 944
6df058c0 945 msg->hdr.tid = cpu_to_le64(flush_tid);
a8599bd8 946
6df058c0 947 fc = msg->front.iov_base;
a8599bd8
SW
948 memset(fc, 0, sizeof(*fc));
949
950 fc->cap_id = cpu_to_le64(cid);
951 fc->op = cpu_to_le32(op);
952 fc->seq = cpu_to_le32(seq);
a8599bd8
SW
953 fc->issue_seq = cpu_to_le32(issue_seq);
954 fc->migrate_seq = cpu_to_le32(mseq);
955 fc->caps = cpu_to_le32(caps);
956 fc->wanted = cpu_to_le32(wanted);
957 fc->dirty = cpu_to_le32(dirty);
958 fc->ino = cpu_to_le64(ino);
959 fc->snap_follows = cpu_to_le64(follows);
960
961 fc->size = cpu_to_le64(size);
962 fc->max_size = cpu_to_le64(max_size);
963 if (mtime)
964 ceph_encode_timespec(&fc->mtime, mtime);
965 if (atime)
966 ceph_encode_timespec(&fc->atime, atime);
967 fc->time_warp_seq = cpu_to_le32(time_warp_seq);
968
969 fc->uid = cpu_to_le32(uid);
970 fc->gid = cpu_to_le32(gid);
971 fc->mode = cpu_to_le32(mode);
972
973 fc->xattr_version = cpu_to_le64(xattr_version);
974 if (xattrs_buf) {
975 msg->middle = ceph_buffer_get(xattrs_buf);
976 fc->xattr_len = cpu_to_le32(xattrs_buf->vec.iov_len);
977 msg->hdr.middle_len = cpu_to_le32(xattrs_buf->vec.iov_len);
978 }
979
980 ceph_con_send(&session->s_con, msg);
981 return 0;
982}
983
984/*
a6369741
SW
985 * Queue cap releases when an inode is dropped from our cache. Since
986 * inode is about to be destroyed, there is no need for i_lock.
a8599bd8
SW
987 */
988void ceph_queue_caps_release(struct inode *inode)
989{
990 struct ceph_inode_info *ci = ceph_inode(inode);
991 struct rb_node *p;
992
a8599bd8
SW
993 p = rb_first(&ci->i_caps);
994 while (p) {
995 struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
996 struct ceph_mds_session *session = cap->session;
997 struct ceph_msg *msg;
998 struct ceph_mds_cap_release *head;
999 struct ceph_mds_cap_item *item;
1000
1001 spin_lock(&session->s_cap_lock);
1002 BUG_ON(!session->s_num_cap_releases);
1003 msg = list_first_entry(&session->s_cap_releases,
1004 struct ceph_msg, list_head);
1005
1006 dout(" adding %p release to mds%d msg %p (%d left)\n",
1007 inode, session->s_mds, msg, session->s_num_cap_releases);
1008
1009 BUG_ON(msg->front.iov_len + sizeof(*item) > PAGE_CACHE_SIZE);
1010 head = msg->front.iov_base;
1011 head->num = cpu_to_le32(le32_to_cpu(head->num) + 1);
1012 item = msg->front.iov_base + msg->front.iov_len;
1013 item->ino = cpu_to_le64(ceph_ino(inode));
1014 item->cap_id = cpu_to_le64(cap->cap_id);
1015 item->migrate_seq = cpu_to_le32(cap->mseq);
1016 item->seq = cpu_to_le32(cap->issue_seq);
1017
1018 session->s_num_cap_releases--;
1019
1020 msg->front.iov_len += sizeof(*item);
1021 if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
1022 dout(" release msg %p full\n", msg);
1023 list_move_tail(&msg->list_head,
afcdaea3 1024 &session->s_cap_releases_done);
a8599bd8
SW
1025 } else {
1026 dout(" release msg %p at %d/%d (%d)\n", msg,
1027 (int)le32_to_cpu(head->num),
1028 (int)CEPH_CAPS_PER_RELEASE,
1029 (int)msg->front.iov_len);
1030 }
1031 spin_unlock(&session->s_cap_lock);
1032 p = rb_next(p);
7c1332b8 1033 __ceph_remove_cap(cap);
a8599bd8 1034 }
a8599bd8
SW
1035}
1036
1037/*
1038 * Send a cap msg on the given inode. Update our caps state, then
1039 * drop i_lock and send the message.
1040 *
1041 * Make note of max_size reported/requested from mds, revoked caps
1042 * that have now been implemented.
1043 *
1044 * Make half-hearted attempt ot to invalidate page cache if we are
1045 * dropping RDCACHE. Note that this will leave behind locked pages
1046 * that we'll then need to deal with elsewhere.
1047 *
1048 * Return non-zero if delayed release, or we experienced an error
1049 * such that the caller should requeue + retry later.
1050 *
1051 * called with i_lock, then drops it.
1052 * caller should hold snap_rwsem (read), s_mutex.
1053 */
1054static int __send_cap(struct ceph_mds_client *mdsc, struct ceph_cap *cap,
1055 int op, int used, int want, int retain, int flushing,
1056 unsigned *pflush_tid)
1057 __releases(cap->ci->vfs_inode->i_lock)
1058{
1059 struct ceph_inode_info *ci = cap->ci;
1060 struct inode *inode = &ci->vfs_inode;
1061 u64 cap_id = cap->cap_id;
68c28323 1062 int held, revoking, dropping, keep;
a8599bd8
SW
1063 u64 seq, issue_seq, mseq, time_warp_seq, follows;
1064 u64 size, max_size;
1065 struct timespec mtime, atime;
1066 int wake = 0;
1067 mode_t mode;
1068 uid_t uid;
1069 gid_t gid;
1070 struct ceph_mds_session *session;
1071 u64 xattr_version = 0;
1072 int delayed = 0;
1073 u64 flush_tid = 0;
1074 int i;
1075 int ret;
1076
68c28323
SW
1077 held = cap->issued | cap->implemented;
1078 revoking = cap->implemented & ~cap->issued;
1079 retain &= ~revoking;
1080 dropping = cap->issued & ~retain;
1081
a8599bd8
SW
1082 dout("__send_cap %p cap %p session %p %s -> %s (revoking %s)\n",
1083 inode, cap, cap->session,
1084 ceph_cap_string(held), ceph_cap_string(held & retain),
1085 ceph_cap_string(revoking));
1086 BUG_ON((retain & CEPH_CAP_PIN) == 0);
1087
1088 session = cap->session;
1089
1090 /* don't release wanted unless we've waited a bit. */
1091 if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1092 time_before(jiffies, ci->i_hold_caps_min)) {
1093 dout(" delaying issued %s -> %s, wanted %s -> %s on send\n",
1094 ceph_cap_string(cap->issued),
1095 ceph_cap_string(cap->issued & retain),
1096 ceph_cap_string(cap->mds_wanted),
1097 ceph_cap_string(want));
1098 want |= cap->mds_wanted;
1099 retain |= cap->issued;
1100 delayed = 1;
1101 }
1102 ci->i_ceph_flags &= ~(CEPH_I_NODELAY | CEPH_I_FLUSH);
1103
1104 cap->issued &= retain; /* drop bits we don't want */
1105 if (cap->implemented & ~cap->issued) {
1106 /*
1107 * Wake up any waiters on wanted -> needed transition.
1108 * This is due to the weird transition from buffered
1109 * to sync IO... we need to flush dirty pages _before_
1110 * allowing sync writes to avoid reordering.
1111 */
1112 wake = 1;
1113 }
1114 cap->implemented &= cap->issued | used;
1115 cap->mds_wanted = want;
1116
1117 if (flushing) {
1118 /*
1119 * assign a tid for flush operations so we can avoid
1120 * flush1 -> dirty1 -> flush2 -> flushack1 -> mark
1121 * clean type races. track latest tid for every bit
1122 * so we can handle flush AxFw, flush Fw, and have the
1123 * first ack clean Ax.
1124 */
1125 flush_tid = ++ci->i_cap_flush_last_tid;
1126 if (pflush_tid)
1127 *pflush_tid = flush_tid;
1128 dout(" cap_flush_tid %d\n", (int)flush_tid);
1129 for (i = 0; i < CEPH_CAP_BITS; i++)
1130 if (flushing & (1 << i))
1131 ci->i_cap_flush_tid[i] = flush_tid;
1132 }
1133
1134 keep = cap->implemented;
1135 seq = cap->seq;
1136 issue_seq = cap->issue_seq;
1137 mseq = cap->mseq;
1138 size = inode->i_size;
1139 ci->i_reported_size = size;
1140 max_size = ci->i_wanted_max_size;
1141 ci->i_requested_max_size = max_size;
1142 mtime = inode->i_mtime;
1143 atime = inode->i_atime;
1144 time_warp_seq = ci->i_time_warp_seq;
1145 follows = ci->i_snap_realm->cached_context->seq;
1146 uid = inode->i_uid;
1147 gid = inode->i_gid;
1148 mode = inode->i_mode;
1149
1150 if (dropping & CEPH_CAP_XATTR_EXCL) {
1151 __ceph_build_xattrs_blob(ci);
1152 xattr_version = ci->i_xattrs.version + 1;
1153 }
1154
1155 spin_unlock(&inode->i_lock);
1156
a8599bd8
SW
1157 ret = send_cap_msg(session, ceph_vino(inode).ino, cap_id,
1158 op, keep, want, flushing, seq, flush_tid, issue_seq, mseq,
1159 size, max_size, &mtime, &atime, time_warp_seq,
1160 uid, gid, mode,
1161 xattr_version,
1162 (flushing & CEPH_CAP_XATTR_EXCL) ? ci->i_xattrs.blob : NULL,
1163 follows);
1164 if (ret < 0) {
1165 dout("error sending cap msg, must requeue %p\n", inode);
1166 delayed = 1;
1167 }
1168
1169 if (wake)
1170 wake_up(&ci->i_cap_wq);
1171
1172 return delayed;
1173}
1174
1175/*
1176 * When a snapshot is taken, clients accumulate dirty metadata on
1177 * inodes with capabilities in ceph_cap_snaps to describe the file
1178 * state at the time the snapshot was taken. This must be flushed
1179 * asynchronously back to the MDS once sync writes complete and dirty
1180 * data is written out.
1181 *
1182 * Called under i_lock. Takes s_mutex as needed.
1183 */
1184void __ceph_flush_snaps(struct ceph_inode_info *ci,
1185 struct ceph_mds_session **psession)
1186{
1187 struct inode *inode = &ci->vfs_inode;
1188 int mds;
1189 struct ceph_cap_snap *capsnap;
1190 u32 mseq;
1191 struct ceph_mds_client *mdsc = &ceph_inode_to_client(inode)->mdsc;
1192 struct ceph_mds_session *session = NULL; /* if session != NULL, we hold
1193 session->s_mutex */
1194 u64 next_follows = 0; /* keep track of how far we've gotten through the
1195 i_cap_snaps list, and skip these entries next time
1196 around to avoid an infinite loop */
1197
1198 if (psession)
1199 session = *psession;
1200
1201 dout("__flush_snaps %p\n", inode);
1202retry:
1203 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
1204 /* avoid an infiniute loop after retry */
1205 if (capsnap->follows < next_follows)
1206 continue;
1207 /*
1208 * we need to wait for sync writes to complete and for dirty
1209 * pages to be written out.
1210 */
1211 if (capsnap->dirty_pages || capsnap->writing)
1212 continue;
1213
819ccbfa
SW
1214 /*
1215 * if cap writeback already occurred, we should have dropped
1216 * the capsnap in ceph_put_wrbuffer_cap_refs.
1217 */
1218 BUG_ON(capsnap->dirty == 0);
1219
a8599bd8
SW
1220 /* pick mds, take s_mutex */
1221 mds = __ceph_get_cap_mds(ci, &mseq);
1222 if (session && session->s_mds != mds) {
1223 dout("oops, wrong session %p mutex\n", session);
1224 mutex_unlock(&session->s_mutex);
1225 ceph_put_mds_session(session);
1226 session = NULL;
1227 }
1228 if (!session) {
1229 spin_unlock(&inode->i_lock);
1230 mutex_lock(&mdsc->mutex);
1231 session = __ceph_lookup_mds_session(mdsc, mds);
1232 mutex_unlock(&mdsc->mutex);
1233 if (session) {
1234 dout("inverting session/ino locks on %p\n",
1235 session);
1236 mutex_lock(&session->s_mutex);
1237 }
1238 /*
1239 * if session == NULL, we raced against a cap
1240 * deletion. retry, and we'll get a better
1241 * @mds value next time.
1242 */
1243 spin_lock(&inode->i_lock);
1244 goto retry;
1245 }
1246
1247 capsnap->flush_tid = ++ci->i_cap_flush_last_tid;
1248 atomic_inc(&capsnap->nref);
1249 if (!list_empty(&capsnap->flushing_item))
1250 list_del_init(&capsnap->flushing_item);
1251 list_add_tail(&capsnap->flushing_item,
1252 &session->s_cap_snaps_flushing);
1253 spin_unlock(&inode->i_lock);
1254
1255 dout("flush_snaps %p cap_snap %p follows %lld size %llu\n",
1256 inode, capsnap, next_follows, capsnap->size);
1257 send_cap_msg(session, ceph_vino(inode).ino, 0,
1258 CEPH_CAP_OP_FLUSHSNAP, capsnap->issued, 0,
1259 capsnap->dirty, 0, capsnap->flush_tid, 0, mseq,
1260 capsnap->size, 0,
1261 &capsnap->mtime, &capsnap->atime,
1262 capsnap->time_warp_seq,
1263 capsnap->uid, capsnap->gid, capsnap->mode,
1264 0, NULL,
1265 capsnap->follows);
1266
1267 next_follows = capsnap->follows + 1;
1268 ceph_put_cap_snap(capsnap);
1269
1270 spin_lock(&inode->i_lock);
1271 goto retry;
1272 }
1273
1274 /* we flushed them all; remove this inode from the queue */
1275 spin_lock(&mdsc->snap_flush_lock);
1276 list_del_init(&ci->i_snap_flush_item);
1277 spin_unlock(&mdsc->snap_flush_lock);
1278
1279 if (psession)
1280 *psession = session;
1281 else if (session) {
1282 mutex_unlock(&session->s_mutex);
1283 ceph_put_mds_session(session);
1284 }
1285}
1286
1287static void ceph_flush_snaps(struct ceph_inode_info *ci)
1288{
1289 struct inode *inode = &ci->vfs_inode;
1290
1291 spin_lock(&inode->i_lock);
1292 __ceph_flush_snaps(ci, NULL);
1293 spin_unlock(&inode->i_lock);
1294}
1295
76e3b390
SW
1296/*
1297 * Mark caps dirty. If inode is newly dirty, add to the global dirty
1298 * list.
1299 */
1300void __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask)
1301{
640ef79d
CR
1302 struct ceph_mds_client *mdsc =
1303 &ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
76e3b390
SW
1304 struct inode *inode = &ci->vfs_inode;
1305 int was = ci->i_dirty_caps;
1306 int dirty = 0;
1307
1308 dout("__mark_dirty_caps %p %s dirty %s -> %s\n", &ci->vfs_inode,
1309 ceph_cap_string(mask), ceph_cap_string(was),
1310 ceph_cap_string(was | mask));
1311 ci->i_dirty_caps |= mask;
1312 if (was == 0) {
1313 dout(" inode %p now dirty\n", &ci->vfs_inode);
1314 BUG_ON(!list_empty(&ci->i_dirty_item));
1315 spin_lock(&mdsc->cap_dirty_lock);
1316 list_add(&ci->i_dirty_item, &mdsc->cap_dirty);
1317 spin_unlock(&mdsc->cap_dirty_lock);
1318 if (ci->i_flushing_caps == 0) {
1319 igrab(inode);
1320 dirty |= I_DIRTY_SYNC;
1321 }
1322 }
1323 BUG_ON(list_empty(&ci->i_dirty_item));
1324 if (((was | ci->i_flushing_caps) & CEPH_CAP_FILE_BUFFER) &&
1325 (mask & CEPH_CAP_FILE_BUFFER))
1326 dirty |= I_DIRTY_DATASYNC;
1327 if (dirty)
1328 __mark_inode_dirty(inode, dirty);
1329 __cap_delay_requeue(mdsc, ci);
1330}
1331
a8599bd8
SW
1332/*
1333 * Add dirty inode to the flushing list. Assigned a seq number so we
1334 * can wait for caps to flush without starving.
cdc35f96
SW
1335 *
1336 * Called under i_lock.
a8599bd8 1337 */
cdc35f96 1338static int __mark_caps_flushing(struct inode *inode,
a8599bd8
SW
1339 struct ceph_mds_session *session)
1340{
640ef79d 1341 struct ceph_mds_client *mdsc = &ceph_sb_to_client(inode->i_sb)->mdsc;
a8599bd8 1342 struct ceph_inode_info *ci = ceph_inode(inode);
cdc35f96 1343 int flushing;
50b885b9 1344
cdc35f96 1345 BUG_ON(ci->i_dirty_caps == 0);
a8599bd8 1346 BUG_ON(list_empty(&ci->i_dirty_item));
cdc35f96
SW
1347
1348 flushing = ci->i_dirty_caps;
1349 dout("__mark_caps_flushing flushing %s, flushing_caps %s -> %s\n",
1350 ceph_cap_string(flushing),
1351 ceph_cap_string(ci->i_flushing_caps),
1352 ceph_cap_string(ci->i_flushing_caps | flushing));
1353 ci->i_flushing_caps |= flushing;
1354 ci->i_dirty_caps = 0;
afcdaea3 1355 dout(" inode %p now !dirty\n", inode);
cdc35f96 1356
a8599bd8 1357 spin_lock(&mdsc->cap_dirty_lock);
afcdaea3
SW
1358 list_del_init(&ci->i_dirty_item);
1359
1360 ci->i_cap_flush_seq = ++mdsc->cap_flush_seq;
a8599bd8
SW
1361 if (list_empty(&ci->i_flushing_item)) {
1362 list_add_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1363 mdsc->num_cap_flushing++;
afcdaea3
SW
1364 dout(" inode %p now flushing seq %lld\n", inode,
1365 ci->i_cap_flush_seq);
1366 } else {
1367 list_move_tail(&ci->i_flushing_item, &session->s_cap_flushing);
1368 dout(" inode %p now flushing (more) seq %lld\n", inode,
a8599bd8
SW
1369 ci->i_cap_flush_seq);
1370 }
1371 spin_unlock(&mdsc->cap_dirty_lock);
cdc35f96
SW
1372
1373 return flushing;
a8599bd8
SW
1374}
1375
5ecad6fd
SW
1376/*
1377 * try to invalidate mapping pages without blocking.
1378 */
1379static int mapping_is_empty(struct address_space *mapping)
1380{
1381 struct page *page = find_get_page(mapping, 0);
1382
1383 if (!page)
1384 return 1;
1385
1386 put_page(page);
1387 return 0;
1388}
1389
1390static int try_nonblocking_invalidate(struct inode *inode)
1391{
1392 struct ceph_inode_info *ci = ceph_inode(inode);
1393 u32 invalidating_gen = ci->i_rdcache_gen;
1394
1395 spin_unlock(&inode->i_lock);
1396 invalidate_mapping_pages(&inode->i_data, 0, -1);
1397 spin_lock(&inode->i_lock);
1398
1399 if (mapping_is_empty(&inode->i_data) &&
1400 invalidating_gen == ci->i_rdcache_gen) {
1401 /* success. */
1402 dout("try_nonblocking_invalidate %p success\n", inode);
1403 ci->i_rdcache_gen = 0;
1404 ci->i_rdcache_revoking = 0;
1405 return 0;
1406 }
1407 dout("try_nonblocking_invalidate %p failed\n", inode);
1408 return -1;
1409}
1410
a8599bd8
SW
1411/*
1412 * Swiss army knife function to examine currently used and wanted
1413 * versus held caps. Release, flush, ack revoked caps to mds as
1414 * appropriate.
1415 *
1416 * CHECK_CAPS_NODELAY - caller is delayed work and we should not delay
1417 * cap release further.
1418 * CHECK_CAPS_AUTHONLY - we should only check the auth cap
1419 * CHECK_CAPS_FLUSH - we should flush any dirty caps immediately, without
1420 * further delay.
1421 */
1422void ceph_check_caps(struct ceph_inode_info *ci, int flags,
1423 struct ceph_mds_session *session)
cdc2ce05 1424 __releases(session->s_mutex)
a8599bd8
SW
1425{
1426 struct ceph_client *client = ceph_inode_to_client(&ci->vfs_inode);
1427 struct ceph_mds_client *mdsc = &client->mdsc;
1428 struct inode *inode = &ci->vfs_inode;
1429 struct ceph_cap *cap;
1430 int file_wanted, used;
1431 int took_snap_rwsem = 0; /* true if mdsc->snap_rwsem held */
cbd03635 1432 int issued, implemented, want, retain, revoking, flushing = 0;
a8599bd8
SW
1433 int mds = -1; /* keep track of how far we've gone through i_caps list
1434 to avoid an infinite loop on retry */
1435 struct rb_node *p;
1436 int tried_invalidate = 0;
1437 int delayed = 0, sent = 0, force_requeue = 0, num;
cbd03635 1438 int queue_invalidate = 0;
a8599bd8
SW
1439 int is_delayed = flags & CHECK_CAPS_NODELAY;
1440
1441 /* if we are unmounting, flush any unused caps immediately. */
1442 if (mdsc->stopping)
1443 is_delayed = 1;
1444
1445 spin_lock(&inode->i_lock);
1446
1447 if (ci->i_ceph_flags & CEPH_I_FLUSH)
1448 flags |= CHECK_CAPS_FLUSH;
1449
1450 /* flush snaps first time around only */
1451 if (!list_empty(&ci->i_cap_snaps))
1452 __ceph_flush_snaps(ci, &session);
1453 goto retry_locked;
1454retry:
1455 spin_lock(&inode->i_lock);
1456retry_locked:
1457 file_wanted = __ceph_caps_file_wanted(ci);
1458 used = __ceph_caps_used(ci);
1459 want = file_wanted | used;
cbd03635
SW
1460 issued = __ceph_caps_issued(ci, &implemented);
1461 revoking = implemented & ~issued;
a8599bd8
SW
1462
1463 retain = want | CEPH_CAP_PIN;
1464 if (!mdsc->stopping && inode->i_nlink > 0) {
1465 if (want) {
1466 retain |= CEPH_CAP_ANY; /* be greedy */
1467 } else {
1468 retain |= CEPH_CAP_ANY_SHARED;
1469 /*
1470 * keep RD only if we didn't have the file open RW,
1471 * because then the mds would revoke it anyway to
1472 * journal max_size=0.
1473 */
1474 if (ci->i_max_size == 0)
1475 retain |= CEPH_CAP_ANY_RD;
1476 }
1477 }
1478
1479 dout("check_caps %p file_want %s used %s dirty %s flushing %s"
cbd03635 1480 " issued %s revoking %s retain %s %s%s%s\n", inode,
a8599bd8
SW
1481 ceph_cap_string(file_wanted),
1482 ceph_cap_string(used), ceph_cap_string(ci->i_dirty_caps),
1483 ceph_cap_string(ci->i_flushing_caps),
cbd03635 1484 ceph_cap_string(issued), ceph_cap_string(revoking),
a8599bd8
SW
1485 ceph_cap_string(retain),
1486 (flags & CHECK_CAPS_AUTHONLY) ? " AUTHONLY" : "",
1487 (flags & CHECK_CAPS_NODELAY) ? " NODELAY" : "",
1488 (flags & CHECK_CAPS_FLUSH) ? " FLUSH" : "");
1489
1490 /*
1491 * If we no longer need to hold onto old our caps, and we may
1492 * have cached pages, but don't want them, then try to invalidate.
1493 * If we fail, it's because pages are locked.... try again later.
1494 */
1495 if ((!is_delayed || mdsc->stopping) &&
1496 ci->i_wrbuffer_ref == 0 && /* no dirty pages... */
1497 ci->i_rdcache_gen && /* may have cached pages */
cbd03635
SW
1498 (file_wanted == 0 || /* no open files */
1499 (revoking & CEPH_CAP_FILE_CACHE)) && /* or revoking cache */
a8599bd8 1500 !tried_invalidate) {
a8599bd8 1501 dout("check_caps trying to invalidate on %p\n", inode);
5ecad6fd
SW
1502 if (try_nonblocking_invalidate(inode) < 0) {
1503 if (revoking & CEPH_CAP_FILE_CACHE) {
1504 dout("check_caps queuing invalidate\n");
1505 queue_invalidate = 1;
1506 ci->i_rdcache_revoking = ci->i_rdcache_gen;
1507 } else {
1508 dout("check_caps failed to invalidate pages\n");
1509 /* we failed to invalidate pages. check these
1510 caps again later. */
1511 force_requeue = 1;
1512 __cap_set_timeouts(mdsc, ci);
1513 }
a8599bd8
SW
1514 }
1515 tried_invalidate = 1;
1516 goto retry_locked;
1517 }
1518
1519 num = 0;
1520 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
1521 cap = rb_entry(p, struct ceph_cap, ci_node);
1522 num++;
1523
1524 /* avoid looping forever */
1525 if (mds >= cap->mds ||
1526 ((flags & CHECK_CAPS_AUTHONLY) && cap != ci->i_auth_cap))
1527 continue;
1528
1529 /* NOTE: no side-effects allowed, until we take s_mutex */
1530
1531 revoking = cap->implemented & ~cap->issued;
1532 if (revoking)
cbd03635 1533 dout(" mds%d revoking %s\n", cap->mds,
a8599bd8
SW
1534 ceph_cap_string(revoking));
1535
1536 if (cap == ci->i_auth_cap &&
1537 (cap->issued & CEPH_CAP_FILE_WR)) {
1538 /* request larger max_size from MDS? */
1539 if (ci->i_wanted_max_size > ci->i_max_size &&
1540 ci->i_wanted_max_size > ci->i_requested_max_size) {
1541 dout("requesting new max_size\n");
1542 goto ack;
1543 }
1544
1545 /* approaching file_max? */
1546 if ((inode->i_size << 1) >= ci->i_max_size &&
1547 (ci->i_reported_size << 1) < ci->i_max_size) {
1548 dout("i_size approaching max_size\n");
1549 goto ack;
1550 }
1551 }
1552 /* flush anything dirty? */
1553 if (cap == ci->i_auth_cap && (flags & CHECK_CAPS_FLUSH) &&
1554 ci->i_dirty_caps) {
1555 dout("flushing dirty caps\n");
1556 goto ack;
1557 }
1558
1559 /* completed revocation? going down and there are no caps? */
1560 if (revoking && (revoking & used) == 0) {
1561 dout("completed revocation of %s\n",
1562 ceph_cap_string(cap->implemented & ~cap->issued));
1563 goto ack;
1564 }
1565
1566 /* want more caps from mds? */
1567 if (want & ~(cap->mds_wanted | cap->issued))
1568 goto ack;
1569
1570 /* things we might delay */
1571 if ((cap->issued & ~retain) == 0 &&
1572 cap->mds_wanted == want)
1573 continue; /* nope, all good */
1574
1575 if (is_delayed)
1576 goto ack;
1577
1578 /* delay? */
1579 if ((ci->i_ceph_flags & CEPH_I_NODELAY) == 0 &&
1580 time_before(jiffies, ci->i_hold_caps_max)) {
1581 dout(" delaying issued %s -> %s, wanted %s -> %s\n",
1582 ceph_cap_string(cap->issued),
1583 ceph_cap_string(cap->issued & retain),
1584 ceph_cap_string(cap->mds_wanted),
1585 ceph_cap_string(want));
1586 delayed++;
1587 continue;
1588 }
1589
1590ack:
e9964c10
SW
1591 if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1592 dout(" skipping %p I_NOFLUSH set\n", inode);
1593 continue;
1594 }
1595
a8599bd8
SW
1596 if (session && session != cap->session) {
1597 dout("oops, wrong session %p mutex\n", session);
1598 mutex_unlock(&session->s_mutex);
1599 session = NULL;
1600 }
1601 if (!session) {
1602 session = cap->session;
1603 if (mutex_trylock(&session->s_mutex) == 0) {
1604 dout("inverting session/ino locks on %p\n",
1605 session);
1606 spin_unlock(&inode->i_lock);
1607 if (took_snap_rwsem) {
1608 up_read(&mdsc->snap_rwsem);
1609 took_snap_rwsem = 0;
1610 }
1611 mutex_lock(&session->s_mutex);
1612 goto retry;
1613 }
1614 }
1615 /* take snap_rwsem after session mutex */
1616 if (!took_snap_rwsem) {
1617 if (down_read_trylock(&mdsc->snap_rwsem) == 0) {
1618 dout("inverting snap/in locks on %p\n",
1619 inode);
1620 spin_unlock(&inode->i_lock);
1621 down_read(&mdsc->snap_rwsem);
1622 took_snap_rwsem = 1;
1623 goto retry;
1624 }
1625 took_snap_rwsem = 1;
1626 }
1627
cdc35f96
SW
1628 if (cap == ci->i_auth_cap && ci->i_dirty_caps)
1629 flushing = __mark_caps_flushing(inode, session);
a8599bd8
SW
1630
1631 mds = cap->mds; /* remember mds, so we don't repeat */
1632 sent++;
1633
1634 /* __send_cap drops i_lock */
1635 delayed += __send_cap(mdsc, cap, CEPH_CAP_OP_UPDATE, used, want,
1636 retain, flushing, NULL);
1637 goto retry; /* retake i_lock and restart our cap scan. */
1638 }
1639
1640 /*
1641 * Reschedule delayed caps release if we delayed anything,
1642 * otherwise cancel.
1643 */
1644 if (delayed && is_delayed)
1645 force_requeue = 1; /* __send_cap delayed release; requeue */
1646 if (!delayed && !is_delayed)
1647 __cap_delay_cancel(mdsc, ci);
1648 else if (!is_delayed || force_requeue)
1649 __cap_delay_requeue(mdsc, ci);
1650
1651 spin_unlock(&inode->i_lock);
1652
cbd03635 1653 if (queue_invalidate)
3c6f6b79 1654 ceph_queue_invalidate(inode);
cbd03635 1655
cdc2ce05 1656 if (session)
a8599bd8
SW
1657 mutex_unlock(&session->s_mutex);
1658 if (took_snap_rwsem)
1659 up_read(&mdsc->snap_rwsem);
1660}
1661
a8599bd8
SW
1662/*
1663 * Try to flush dirty caps back to the auth mds.
1664 */
1665static int try_flush_caps(struct inode *inode, struct ceph_mds_session *session,
1666 unsigned *flush_tid)
1667{
640ef79d 1668 struct ceph_mds_client *mdsc = &ceph_sb_to_client(inode->i_sb)->mdsc;
a8599bd8
SW
1669 struct ceph_inode_info *ci = ceph_inode(inode);
1670 int unlock_session = session ? 0 : 1;
1671 int flushing = 0;
1672
1673retry:
1674 spin_lock(&inode->i_lock);
e9964c10
SW
1675 if (ci->i_ceph_flags & CEPH_I_NOFLUSH) {
1676 dout("try_flush_caps skipping %p I_NOFLUSH set\n", inode);
1677 goto out;
1678 }
a8599bd8
SW
1679 if (ci->i_dirty_caps && ci->i_auth_cap) {
1680 struct ceph_cap *cap = ci->i_auth_cap;
1681 int used = __ceph_caps_used(ci);
1682 int want = __ceph_caps_wanted(ci);
1683 int delayed;
1684
1685 if (!session) {
1686 spin_unlock(&inode->i_lock);
1687 session = cap->session;
1688 mutex_lock(&session->s_mutex);
1689 goto retry;
1690 }
1691 BUG_ON(session != cap->session);
1692 if (cap->session->s_state < CEPH_MDS_SESSION_OPEN)
1693 goto out;
1694
cdc35f96 1695 flushing = __mark_caps_flushing(inode, session);
a8599bd8
SW
1696
1697 /* __send_cap drops i_lock */
1698 delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH, used, want,
1699 cap->issued | cap->implemented, flushing,
1700 flush_tid);
1701 if (!delayed)
1702 goto out_unlocked;
1703
1704 spin_lock(&inode->i_lock);
1705 __cap_delay_requeue(mdsc, ci);
1706 }
1707out:
1708 spin_unlock(&inode->i_lock);
1709out_unlocked:
1710 if (session && unlock_session)
1711 mutex_unlock(&session->s_mutex);
1712 return flushing;
1713}
1714
1715/*
1716 * Return true if we've flushed caps through the given flush_tid.
1717 */
1718static int caps_are_flushed(struct inode *inode, unsigned tid)
1719{
1720 struct ceph_inode_info *ci = ceph_inode(inode);
1721 int dirty, i, ret = 1;
1722
1723 spin_lock(&inode->i_lock);
1724 dirty = __ceph_caps_dirty(ci);
1725 for (i = 0; i < CEPH_CAP_BITS; i++)
1726 if ((ci->i_flushing_caps & (1 << i)) &&
1727 ci->i_cap_flush_tid[i] <= tid) {
1728 /* still flushing this bit */
1729 ret = 0;
1730 break;
1731 }
1732 spin_unlock(&inode->i_lock);
1733 return ret;
1734}
1735
1736/*
1737 * Wait on any unsafe replies for the given inode. First wait on the
1738 * newest request, and make that the upper bound. Then, if there are
1739 * more requests, keep waiting on the oldest as long as it is still older
1740 * than the original request.
1741 */
1742static void sync_write_wait(struct inode *inode)
1743{
1744 struct ceph_inode_info *ci = ceph_inode(inode);
1745 struct list_head *head = &ci->i_unsafe_writes;
1746 struct ceph_osd_request *req;
1747 u64 last_tid;
1748
1749 spin_lock(&ci->i_unsafe_lock);
1750 if (list_empty(head))
1751 goto out;
1752
1753 /* set upper bound as _last_ entry in chain */
1754 req = list_entry(head->prev, struct ceph_osd_request,
1755 r_unsafe_item);
1756 last_tid = req->r_tid;
1757
1758 do {
1759 ceph_osdc_get_request(req);
1760 spin_unlock(&ci->i_unsafe_lock);
1761 dout("sync_write_wait on tid %llu (until %llu)\n",
1762 req->r_tid, last_tid);
1763 wait_for_completion(&req->r_safe_completion);
1764 spin_lock(&ci->i_unsafe_lock);
1765 ceph_osdc_put_request(req);
1766
1767 /*
1768 * from here on look at first entry in chain, since we
1769 * only want to wait for anything older than last_tid
1770 */
1771 if (list_empty(head))
1772 break;
1773 req = list_entry(head->next, struct ceph_osd_request,
1774 r_unsafe_item);
1775 } while (req->r_tid < last_tid);
1776out:
1777 spin_unlock(&ci->i_unsafe_lock);
1778}
1779
1780int ceph_fsync(struct file *file, struct dentry *dentry, int datasync)
1781{
1782 struct inode *inode = dentry->d_inode;
1783 struct ceph_inode_info *ci = ceph_inode(inode);
1784 unsigned flush_tid;
1785 int ret;
1786 int dirty;
1787
1788 dout("fsync %p%s\n", inode, datasync ? " datasync" : "");
1789 sync_write_wait(inode);
1790
1791 ret = filemap_write_and_wait(inode->i_mapping);
1792 if (ret < 0)
1793 return ret;
1794
1795 dirty = try_flush_caps(inode, NULL, &flush_tid);
1796 dout("fsync dirty caps are %s\n", ceph_cap_string(dirty));
1797
1798 /*
1799 * only wait on non-file metadata writeback (the mds
1800 * can recover size and mtime, so we don't need to
1801 * wait for that)
1802 */
1803 if (!datasync && (dirty & ~CEPH_CAP_ANY_FILE_WR)) {
1804 dout("fsync waiting for flush_tid %u\n", flush_tid);
1805 ret = wait_event_interruptible(ci->i_cap_wq,
1806 caps_are_flushed(inode, flush_tid));
1807 }
1808
1809 dout("fsync %p%s done\n", inode, datasync ? " datasync" : "");
1810 return ret;
1811}
1812
1813/*
1814 * Flush any dirty caps back to the mds. If we aren't asked to wait,
1815 * queue inode for flush but don't do so immediately, because we can
1816 * get by with fewer MDS messages if we wait for data writeback to
1817 * complete first.
1818 */
f1a3d572 1819int ceph_write_inode(struct inode *inode, struct writeback_control *wbc)
a8599bd8
SW
1820{
1821 struct ceph_inode_info *ci = ceph_inode(inode);
1822 unsigned flush_tid;
1823 int err = 0;
1824 int dirty;
f1a3d572 1825 int wait = wbc->sync_mode == WB_SYNC_ALL;
a8599bd8
SW
1826
1827 dout("write_inode %p wait=%d\n", inode, wait);
1828 if (wait) {
1829 dirty = try_flush_caps(inode, NULL, &flush_tid);
1830 if (dirty)
1831 err = wait_event_interruptible(ci->i_cap_wq,
1832 caps_are_flushed(inode, flush_tid));
1833 } else {
640ef79d
CR
1834 struct ceph_mds_client *mdsc =
1835 &ceph_sb_to_client(inode->i_sb)->mdsc;
a8599bd8
SW
1836
1837 spin_lock(&inode->i_lock);
1838 if (__ceph_caps_dirty(ci))
1839 __cap_delay_requeue_front(mdsc, ci);
1840 spin_unlock(&inode->i_lock);
1841 }
1842 return err;
1843}
1844
1845/*
1846 * After a recovering MDS goes active, we need to resend any caps
1847 * we were flushing.
1848 *
1849 * Caller holds session->s_mutex.
1850 */
1851static void kick_flushing_capsnaps(struct ceph_mds_client *mdsc,
1852 struct ceph_mds_session *session)
1853{
1854 struct ceph_cap_snap *capsnap;
1855
1856 dout("kick_flushing_capsnaps mds%d\n", session->s_mds);
1857 list_for_each_entry(capsnap, &session->s_cap_snaps_flushing,
1858 flushing_item) {
1859 struct ceph_inode_info *ci = capsnap->ci;
1860 struct inode *inode = &ci->vfs_inode;
1861 struct ceph_cap *cap;
1862
1863 spin_lock(&inode->i_lock);
1864 cap = ci->i_auth_cap;
1865 if (cap && cap->session == session) {
1866 dout("kick_flushing_caps %p cap %p capsnap %p\n", inode,
1867 cap, capsnap);
1868 __ceph_flush_snaps(ci, &session);
1869 } else {
1870 pr_err("%p auth cap %p not mds%d ???\n", inode,
1871 cap, session->s_mds);
a8599bd8 1872 }
0b0c06d1 1873 spin_unlock(&inode->i_lock);
a8599bd8
SW
1874 }
1875}
1876
1877void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
1878 struct ceph_mds_session *session)
1879{
1880 struct ceph_inode_info *ci;
1881
1882 kick_flushing_capsnaps(mdsc, session);
1883
1884 dout("kick_flushing_caps mds%d\n", session->s_mds);
1885 list_for_each_entry(ci, &session->s_cap_flushing, i_flushing_item) {
1886 struct inode *inode = &ci->vfs_inode;
1887 struct ceph_cap *cap;
1888 int delayed = 0;
1889
1890 spin_lock(&inode->i_lock);
1891 cap = ci->i_auth_cap;
1892 if (cap && cap->session == session) {
1893 dout("kick_flushing_caps %p cap %p %s\n", inode,
1894 cap, ceph_cap_string(ci->i_flushing_caps));
1895 delayed = __send_cap(mdsc, cap, CEPH_CAP_OP_FLUSH,
1896 __ceph_caps_used(ci),
1897 __ceph_caps_wanted(ci),
1898 cap->issued | cap->implemented,
1899 ci->i_flushing_caps, NULL);
1900 if (delayed) {
1901 spin_lock(&inode->i_lock);
1902 __cap_delay_requeue(mdsc, ci);
1903 spin_unlock(&inode->i_lock);
1904 }
1905 } else {
1906 pr_err("%p auth cap %p not mds%d ???\n", inode,
1907 cap, session->s_mds);
1908 spin_unlock(&inode->i_lock);
1909 }
1910 }
1911}
1912
1913
1914/*
1915 * Take references to capabilities we hold, so that we don't release
1916 * them to the MDS prematurely.
1917 *
1918 * Protected by i_lock.
1919 */
1920static void __take_cap_refs(struct ceph_inode_info *ci, int got)
1921{
1922 if (got & CEPH_CAP_PIN)
1923 ci->i_pin_ref++;
1924 if (got & CEPH_CAP_FILE_RD)
1925 ci->i_rd_ref++;
1926 if (got & CEPH_CAP_FILE_CACHE)
1927 ci->i_rdcache_ref++;
1928 if (got & CEPH_CAP_FILE_WR)
1929 ci->i_wr_ref++;
1930 if (got & CEPH_CAP_FILE_BUFFER) {
1931 if (ci->i_wrbuffer_ref == 0)
1932 igrab(&ci->vfs_inode);
1933 ci->i_wrbuffer_ref++;
1934 dout("__take_cap_refs %p wrbuffer %d -> %d (?)\n",
1935 &ci->vfs_inode, ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref);
1936 }
1937}
1938
1939/*
1940 * Try to grab cap references. Specify those refs we @want, and the
1941 * minimal set we @need. Also include the larger offset we are writing
1942 * to (when applicable), and check against max_size here as well.
1943 * Note that caller is responsible for ensuring max_size increases are
1944 * requested from the MDS.
1945 */
1946static int try_get_cap_refs(struct ceph_inode_info *ci, int need, int want,
1947 int *got, loff_t endoff, int *check_max, int *err)
1948{
1949 struct inode *inode = &ci->vfs_inode;
1950 int ret = 0;
1951 int have, implemented;
195d3ce2 1952 int file_wanted;
a8599bd8
SW
1953
1954 dout("get_cap_refs %p need %s want %s\n", inode,
1955 ceph_cap_string(need), ceph_cap_string(want));
1956 spin_lock(&inode->i_lock);
1957
195d3ce2
SW
1958 /* make sure file is actually open */
1959 file_wanted = __ceph_caps_file_wanted(ci);
1960 if ((file_wanted & need) == 0) {
1961 dout("try_get_cap_refs need %s file_wanted %s, EBADF\n",
1962 ceph_cap_string(need), ceph_cap_string(file_wanted));
a8599bd8
SW
1963 *err = -EBADF;
1964 ret = 1;
1965 goto out;
1966 }
1967
1968 if (need & CEPH_CAP_FILE_WR) {
1969 if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
1970 dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
1971 inode, endoff, ci->i_max_size);
1972 if (endoff > ci->i_wanted_max_size) {
1973 *check_max = 1;
1974 ret = 1;
1975 }
1976 goto out;
1977 }
1978 /*
1979 * If a sync write is in progress, we must wait, so that we
1980 * can get a final snapshot value for size+mtime.
1981 */
1982 if (__ceph_have_pending_cap_snap(ci)) {
1983 dout("get_cap_refs %p cap_snap_pending\n", inode);
1984 goto out;
1985 }
1986 }
1987 have = __ceph_caps_issued(ci, &implemented);
1988
1989 /*
1990 * disallow writes while a truncate is pending
1991 */
1992 if (ci->i_truncate_pending)
1993 have &= ~CEPH_CAP_FILE_WR;
1994
1995 if ((have & need) == need) {
1996 /*
1997 * Look at (implemented & ~have & not) so that we keep waiting
1998 * on transition from wanted -> needed caps. This is needed
1999 * for WRBUFFER|WR -> WR to avoid a new WR sync write from
2000 * going before a prior buffered writeback happens.
2001 */
2002 int not = want & ~(have & need);
2003 int revoking = implemented & ~have;
2004 dout("get_cap_refs %p have %s but not %s (revoking %s)\n",
2005 inode, ceph_cap_string(have), ceph_cap_string(not),
2006 ceph_cap_string(revoking));
2007 if ((revoking & not) == 0) {
2008 *got = need | (have & want);
2009 __take_cap_refs(ci, *got);
2010 ret = 1;
2011 }
2012 } else {
2013 dout("get_cap_refs %p have %s needed %s\n", inode,
2014 ceph_cap_string(have), ceph_cap_string(need));
2015 }
2016out:
2017 spin_unlock(&inode->i_lock);
2018 dout("get_cap_refs %p ret %d got %s\n", inode,
2019 ret, ceph_cap_string(*got));
2020 return ret;
2021}
2022
2023/*
2024 * Check the offset we are writing up to against our current
2025 * max_size. If necessary, tell the MDS we want to write to
2026 * a larger offset.
2027 */
2028static void check_max_size(struct inode *inode, loff_t endoff)
2029{
2030 struct ceph_inode_info *ci = ceph_inode(inode);
2031 int check = 0;
2032
2033 /* do we need to explicitly request a larger max_size? */
2034 spin_lock(&inode->i_lock);
2035 if ((endoff >= ci->i_max_size ||
2036 endoff > (inode->i_size << 1)) &&
2037 endoff > ci->i_wanted_max_size) {
2038 dout("write %p at large endoff %llu, req max_size\n",
2039 inode, endoff);
2040 ci->i_wanted_max_size = endoff;
2041 check = 1;
2042 }
2043 spin_unlock(&inode->i_lock);
2044 if (check)
2045 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2046}
2047
2048/*
2049 * Wait for caps, and take cap references. If we can't get a WR cap
2050 * due to a small max_size, make sure we check_max_size (and possibly
2051 * ask the mds) so we don't get hung up indefinitely.
2052 */
2053int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, int *got,
2054 loff_t endoff)
2055{
2056 int check_max, ret, err;
2057
2058retry:
2059 if (endoff > 0)
2060 check_max_size(&ci->vfs_inode, endoff);
2061 check_max = 0;
2062 err = 0;
2063 ret = wait_event_interruptible(ci->i_cap_wq,
2064 try_get_cap_refs(ci, need, want,
2065 got, endoff,
2066 &check_max, &err));
2067 if (err)
2068 ret = err;
2069 if (check_max)
2070 goto retry;
2071 return ret;
2072}
2073
2074/*
2075 * Take cap refs. Caller must already know we hold at least one ref
2076 * on the caps in question or we don't know this is safe.
2077 */
2078void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps)
2079{
2080 spin_lock(&ci->vfs_inode.i_lock);
2081 __take_cap_refs(ci, caps);
2082 spin_unlock(&ci->vfs_inode.i_lock);
2083}
2084
2085/*
2086 * Release cap refs.
2087 *
2088 * If we released the last ref on any given cap, call ceph_check_caps
2089 * to release (or schedule a release).
2090 *
2091 * If we are releasing a WR cap (from a sync write), finalize any affected
2092 * cap_snap, and wake up any waiters.
2093 */
2094void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
2095{
2096 struct inode *inode = &ci->vfs_inode;
2097 int last = 0, put = 0, flushsnaps = 0, wake = 0;
2098 struct ceph_cap_snap *capsnap;
2099
2100 spin_lock(&inode->i_lock);
2101 if (had & CEPH_CAP_PIN)
2102 --ci->i_pin_ref;
2103 if (had & CEPH_CAP_FILE_RD)
2104 if (--ci->i_rd_ref == 0)
2105 last++;
2106 if (had & CEPH_CAP_FILE_CACHE)
2107 if (--ci->i_rdcache_ref == 0)
2108 last++;
2109 if (had & CEPH_CAP_FILE_BUFFER) {
2110 if (--ci->i_wrbuffer_ref == 0) {
2111 last++;
2112 put++;
2113 }
2114 dout("put_cap_refs %p wrbuffer %d -> %d (?)\n",
2115 inode, ci->i_wrbuffer_ref+1, ci->i_wrbuffer_ref);
2116 }
2117 if (had & CEPH_CAP_FILE_WR)
2118 if (--ci->i_wr_ref == 0) {
2119 last++;
2120 if (!list_empty(&ci->i_cap_snaps)) {
2121 capsnap = list_first_entry(&ci->i_cap_snaps,
2122 struct ceph_cap_snap,
2123 ci_item);
2124 if (capsnap->writing) {
2125 capsnap->writing = 0;
2126 flushsnaps =
2127 __ceph_finish_cap_snap(ci,
2128 capsnap);
2129 wake = 1;
2130 }
2131 }
2132 }
2133 spin_unlock(&inode->i_lock);
2134
819ccbfa
SW
2135 dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
2136 last ? " last" : "", put ? " put" : "");
a8599bd8
SW
2137
2138 if (last && !flushsnaps)
2139 ceph_check_caps(ci, 0, NULL);
2140 else if (flushsnaps)
2141 ceph_flush_snaps(ci);
2142 if (wake)
2143 wake_up(&ci->i_cap_wq);
2144 if (put)
2145 iput(inode);
2146}
2147
2148/*
2149 * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
2150 * context. Adjust per-snap dirty page accounting as appropriate.
2151 * Once all dirty data for a cap_snap is flushed, flush snapped file
2152 * metadata back to the MDS. If we dropped the last ref, call
2153 * ceph_check_caps.
2154 */
2155void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
2156 struct ceph_snap_context *snapc)
2157{
2158 struct inode *inode = &ci->vfs_inode;
2159 int last = 0;
819ccbfa
SW
2160 int complete_capsnap = 0;
2161 int drop_capsnap = 0;
a8599bd8
SW
2162 int found = 0;
2163 struct ceph_cap_snap *capsnap = NULL;
2164
2165 spin_lock(&inode->i_lock);
2166 ci->i_wrbuffer_ref -= nr;
2167 last = !ci->i_wrbuffer_ref;
2168
2169 if (ci->i_head_snapc == snapc) {
2170 ci->i_wrbuffer_ref_head -= nr;
2171 if (!ci->i_wrbuffer_ref_head) {
2172 ceph_put_snap_context(ci->i_head_snapc);
2173 ci->i_head_snapc = NULL;
2174 }
2175 dout("put_wrbuffer_cap_refs on %p head %d/%d -> %d/%d %s\n",
2176 inode,
2177 ci->i_wrbuffer_ref+nr, ci->i_wrbuffer_ref_head+nr,
2178 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
2179 last ? " LAST" : "");
2180 } else {
2181 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2182 if (capsnap->context == snapc) {
2183 found = 1;
a8599bd8
SW
2184 break;
2185 }
2186 }
2187 BUG_ON(!found);
819ccbfa
SW
2188 capsnap->dirty_pages -= nr;
2189 if (capsnap->dirty_pages == 0) {
2190 complete_capsnap = 1;
2191 if (capsnap->dirty == 0)
2192 /* cap writeback completed before we created
2193 * the cap_snap; no FLUSHSNAP is needed */
2194 drop_capsnap = 1;
2195 }
a8599bd8 2196 dout("put_wrbuffer_cap_refs on %p cap_snap %p "
819ccbfa 2197 " snap %lld %d/%d -> %d/%d %s%s%s\n",
a8599bd8
SW
2198 inode, capsnap, capsnap->context->seq,
2199 ci->i_wrbuffer_ref+nr, capsnap->dirty_pages + nr,
2200 ci->i_wrbuffer_ref, capsnap->dirty_pages,
2201 last ? " (wrbuffer last)" : "",
819ccbfa
SW
2202 complete_capsnap ? " (complete capsnap)" : "",
2203 drop_capsnap ? " (drop capsnap)" : "");
2204 if (drop_capsnap) {
2205 ceph_put_snap_context(capsnap->context);
2206 list_del(&capsnap->ci_item);
2207 list_del(&capsnap->flushing_item);
2208 ceph_put_cap_snap(capsnap);
2209 }
a8599bd8
SW
2210 }
2211
2212 spin_unlock(&inode->i_lock);
2213
2214 if (last) {
2215 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
2216 iput(inode);
819ccbfa 2217 } else if (complete_capsnap) {
a8599bd8
SW
2218 ceph_flush_snaps(ci);
2219 wake_up(&ci->i_cap_wq);
2220 }
819ccbfa
SW
2221 if (drop_capsnap)
2222 iput(inode);
a8599bd8
SW
2223}
2224
2225/*
2226 * Handle a cap GRANT message from the MDS. (Note that a GRANT may
2227 * actually be a revocation if it specifies a smaller cap set.)
2228 *
15637c8b
SW
2229 * caller holds s_mutex and i_lock, we drop both.
2230 *
a8599bd8
SW
2231 * return value:
2232 * 0 - ok
2233 * 1 - check_caps on auth cap only (writeback)
2234 * 2 - check_caps (ack revoke)
2235 */
15637c8b
SW
2236static void handle_cap_grant(struct inode *inode, struct ceph_mds_caps *grant,
2237 struct ceph_mds_session *session,
2238 struct ceph_cap *cap,
2239 struct ceph_buffer *xattr_buf)
a8599bd8 2240 __releases(inode->i_lock)
15637c8b 2241 __releases(session->s_mutex)
a8599bd8
SW
2242{
2243 struct ceph_inode_info *ci = ceph_inode(inode);
2244 int mds = session->s_mds;
2245 int seq = le32_to_cpu(grant->seq);
2246 int newcaps = le32_to_cpu(grant->caps);
2247 int issued, implemented, used, wanted, dirty;
2248 u64 size = le64_to_cpu(grant->size);
2249 u64 max_size = le64_to_cpu(grant->max_size);
2250 struct timespec mtime, atime, ctime;
15637c8b 2251 int check_caps = 0;
a8599bd8
SW
2252 int wake = 0;
2253 int writeback = 0;
2254 int revoked_rdcache = 0;
3c6f6b79 2255 int queue_invalidate = 0;
a8599bd8
SW
2256
2257 dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",
2258 inode, cap, mds, seq, ceph_cap_string(newcaps));
2259 dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
2260 inode->i_size);
2261
2262 /*
2263 * If CACHE is being revoked, and we have no dirty buffers,
2264 * try to invalidate (once). (If there are dirty buffers, we
2265 * will invalidate _after_ writeback.)
2266 */
a8599bd8 2267 if (((cap->issued & ~newcaps) & CEPH_CAP_FILE_CACHE) &&
bcd2cbd1 2268 !ci->i_wrbuffer_ref) {
5ecad6fd
SW
2269 if (try_nonblocking_invalidate(inode) == 0) {
2270 revoked_rdcache = 1;
2271 } else {
a8599bd8
SW
2272 /* there were locked pages.. invalidate later
2273 in a separate thread. */
2274 if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
3c6f6b79 2275 queue_invalidate = 1;
a8599bd8
SW
2276 ci->i_rdcache_revoking = ci->i_rdcache_gen;
2277 }
a8599bd8 2278 }
a8599bd8
SW
2279 }
2280
2281 /* side effects now are allowed */
2282
2283 issued = __ceph_caps_issued(ci, &implemented);
2284 issued |= implemented | __ceph_caps_dirty(ci);
2285
685f9a5d 2286 cap->cap_gen = session->s_cap_gen;
a8599bd8
SW
2287
2288 __check_cap_issue(ci, cap, newcaps);
2289
2290 if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
2291 inode->i_mode = le32_to_cpu(grant->mode);
2292 inode->i_uid = le32_to_cpu(grant->uid);
2293 inode->i_gid = le32_to_cpu(grant->gid);
2294 dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
2295 inode->i_uid, inode->i_gid);
2296 }
2297
2298 if ((issued & CEPH_CAP_LINK_EXCL) == 0)
2299 inode->i_nlink = le32_to_cpu(grant->nlink);
2300
2301 if ((issued & CEPH_CAP_XATTR_EXCL) == 0 && grant->xattr_len) {
2302 int len = le32_to_cpu(grant->xattr_len);
2303 u64 version = le64_to_cpu(grant->xattr_version);
2304
2305 if (version > ci->i_xattrs.version) {
2306 dout(" got new xattrs v%llu on %p len %d\n",
2307 version, inode, len);
2308 if (ci->i_xattrs.blob)
2309 ceph_buffer_put(ci->i_xattrs.blob);
2310 ci->i_xattrs.blob = ceph_buffer_get(xattr_buf);
2311 ci->i_xattrs.version = version;
2312 }
2313 }
2314
2315 /* size/ctime/mtime/atime? */
2316 ceph_fill_file_size(inode, issued,
2317 le32_to_cpu(grant->truncate_seq),
2318 le64_to_cpu(grant->truncate_size), size);
2319 ceph_decode_timespec(&mtime, &grant->mtime);
2320 ceph_decode_timespec(&atime, &grant->atime);
2321 ceph_decode_timespec(&ctime, &grant->ctime);
2322 ceph_fill_file_time(inode, issued,
2323 le32_to_cpu(grant->time_warp_seq), &ctime, &mtime,
2324 &atime);
2325
2326 /* max size increase? */
2327 if (max_size != ci->i_max_size) {
2328 dout("max_size %lld -> %llu\n", ci->i_max_size, max_size);
2329 ci->i_max_size = max_size;
2330 if (max_size >= ci->i_wanted_max_size) {
2331 ci->i_wanted_max_size = 0; /* reset */
2332 ci->i_requested_max_size = 0;
2333 }
2334 wake = 1;
2335 }
2336
2337 /* check cap bits */
2338 wanted = __ceph_caps_wanted(ci);
2339 used = __ceph_caps_used(ci);
2340 dirty = __ceph_caps_dirty(ci);
2341 dout(" my wanted = %s, used = %s, dirty %s\n",
2342 ceph_cap_string(wanted),
2343 ceph_cap_string(used),
2344 ceph_cap_string(dirty));
2345 if (wanted != le32_to_cpu(grant->wanted)) {
2346 dout("mds wanted %s -> %s\n",
2347 ceph_cap_string(le32_to_cpu(grant->wanted)),
2348 ceph_cap_string(wanted));
2349 grant->wanted = cpu_to_le32(wanted);
2350 }
2351
2352 cap->seq = seq;
2353
2354 /* file layout may have changed */
2355 ci->i_layout = grant->layout;
2356
2357 /* revocation, grant, or no-op? */
2358 if (cap->issued & ~newcaps) {
2359 dout("revocation: %s -> %s\n", ceph_cap_string(cap->issued),
2360 ceph_cap_string(newcaps));
2361 if ((used & ~newcaps) & CEPH_CAP_FILE_BUFFER)
2362 writeback = 1; /* will delay ack */
2363 else if (dirty & ~newcaps)
15637c8b 2364 check_caps = 1; /* initiate writeback in check_caps */
a8599bd8
SW
2365 else if (((used & ~newcaps) & CEPH_CAP_FILE_CACHE) == 0 ||
2366 revoked_rdcache)
15637c8b 2367 check_caps = 2; /* send revoke ack in check_caps */
a8599bd8 2368 cap->issued = newcaps;
978097c9 2369 cap->implemented |= newcaps;
a8599bd8
SW
2370 } else if (cap->issued == newcaps) {
2371 dout("caps unchanged: %s -> %s\n",
2372 ceph_cap_string(cap->issued), ceph_cap_string(newcaps));
2373 } else {
2374 dout("grant: %s -> %s\n", ceph_cap_string(cap->issued),
2375 ceph_cap_string(newcaps));
2376 cap->issued = newcaps;
2377 cap->implemented |= newcaps; /* add bits only, to
2378 * avoid stepping on a
2379 * pending revocation */
2380 wake = 1;
2381 }
978097c9 2382 BUG_ON(cap->issued & ~cap->implemented);
a8599bd8
SW
2383
2384 spin_unlock(&inode->i_lock);
3c6f6b79 2385 if (writeback)
a8599bd8
SW
2386 /*
2387 * queue inode for writeback: we can't actually call
2388 * filemap_write_and_wait, etc. from message handler
2389 * context.
2390 */
3c6f6b79
SW
2391 ceph_queue_writeback(inode);
2392 if (queue_invalidate)
2393 ceph_queue_invalidate(inode);
a8599bd8
SW
2394 if (wake)
2395 wake_up(&ci->i_cap_wq);
15637c8b
SW
2396
2397 if (check_caps == 1)
2398 ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_AUTHONLY,
2399 session);
2400 else if (check_caps == 2)
2401 ceph_check_caps(ci, CHECK_CAPS_NODELAY, session);
2402 else
2403 mutex_unlock(&session->s_mutex);
a8599bd8
SW
2404}
2405
2406/*
2407 * Handle FLUSH_ACK from MDS, indicating that metadata we sent to the
2408 * MDS has been safely committed.
2409 */
6df058c0 2410static void handle_cap_flush_ack(struct inode *inode, u64 flush_tid,
a8599bd8
SW
2411 struct ceph_mds_caps *m,
2412 struct ceph_mds_session *session,
2413 struct ceph_cap *cap)
2414 __releases(inode->i_lock)
2415{
2416 struct ceph_inode_info *ci = ceph_inode(inode);
640ef79d 2417 struct ceph_mds_client *mdsc = &ceph_sb_to_client(inode->i_sb)->mdsc;
a8599bd8
SW
2418 unsigned seq = le32_to_cpu(m->seq);
2419 int dirty = le32_to_cpu(m->dirty);
2420 int cleaned = 0;
afcdaea3 2421 int drop = 0;
a8599bd8
SW
2422 int i;
2423
2424 for (i = 0; i < CEPH_CAP_BITS; i++)
2425 if ((dirty & (1 << i)) &&
2426 flush_tid == ci->i_cap_flush_tid[i])
2427 cleaned |= 1 << i;
2428
2429 dout("handle_cap_flush_ack inode %p mds%d seq %d on %s cleaned %s,"
2430 " flushing %s -> %s\n",
2431 inode, session->s_mds, seq, ceph_cap_string(dirty),
2432 ceph_cap_string(cleaned), ceph_cap_string(ci->i_flushing_caps),
2433 ceph_cap_string(ci->i_flushing_caps & ~cleaned));
2434
2435 if (ci->i_flushing_caps == (ci->i_flushing_caps & ~cleaned))
2436 goto out;
2437
a8599bd8 2438 ci->i_flushing_caps &= ~cleaned;
a8599bd8
SW
2439
2440 spin_lock(&mdsc->cap_dirty_lock);
2441 if (ci->i_flushing_caps == 0) {
2442 list_del_init(&ci->i_flushing_item);
2443 if (!list_empty(&session->s_cap_flushing))
2444 dout(" mds%d still flushing cap on %p\n",
2445 session->s_mds,
2446 &list_entry(session->s_cap_flushing.next,
2447 struct ceph_inode_info,
2448 i_flushing_item)->vfs_inode);
2449 mdsc->num_cap_flushing--;
2450 wake_up(&mdsc->cap_flushing_wq);
2451 dout(" inode %p now !flushing\n", inode);
afcdaea3
SW
2452
2453 if (ci->i_dirty_caps == 0) {
2454 dout(" inode %p now clean\n", inode);
2455 BUG_ON(!list_empty(&ci->i_dirty_item));
2456 drop = 1;
76e3b390
SW
2457 } else {
2458 BUG_ON(list_empty(&ci->i_dirty_item));
afcdaea3 2459 }
a8599bd8
SW
2460 }
2461 spin_unlock(&mdsc->cap_dirty_lock);
2462 wake_up(&ci->i_cap_wq);
2463
2464out:
2465 spin_unlock(&inode->i_lock);
afcdaea3 2466 if (drop)
a8599bd8
SW
2467 iput(inode);
2468}
2469
2470/*
2471 * Handle FLUSHSNAP_ACK. MDS has flushed snap data to disk and we can
2472 * throw away our cap_snap.
2473 *
2474 * Caller hold s_mutex.
2475 */
6df058c0 2476static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid,
a8599bd8
SW
2477 struct ceph_mds_caps *m,
2478 struct ceph_mds_session *session)
2479{
2480 struct ceph_inode_info *ci = ceph_inode(inode);
2481 u64 follows = le64_to_cpu(m->snap_follows);
a8599bd8
SW
2482 struct ceph_cap_snap *capsnap;
2483 int drop = 0;
2484
2485 dout("handle_cap_flushsnap_ack inode %p ci %p mds%d follows %lld\n",
2486 inode, ci, session->s_mds, follows);
2487
2488 spin_lock(&inode->i_lock);
2489 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
2490 if (capsnap->follows == follows) {
2491 if (capsnap->flush_tid != flush_tid) {
2492 dout(" cap_snap %p follows %lld tid %lld !="
2493 " %lld\n", capsnap, follows,
2494 flush_tid, capsnap->flush_tid);
2495 break;
2496 }
2497 WARN_ON(capsnap->dirty_pages || capsnap->writing);
819ccbfa
SW
2498 dout(" removing %p cap_snap %p follows %lld\n",
2499 inode, capsnap, follows);
a8599bd8
SW
2500 ceph_put_snap_context(capsnap->context);
2501 list_del(&capsnap->ci_item);
2502 list_del(&capsnap->flushing_item);
2503 ceph_put_cap_snap(capsnap);
2504 drop = 1;
2505 break;
2506 } else {
2507 dout(" skipping cap_snap %p follows %lld\n",
2508 capsnap, capsnap->follows);
2509 }
2510 }
2511 spin_unlock(&inode->i_lock);
2512 if (drop)
2513 iput(inode);
2514}
2515
2516/*
2517 * Handle TRUNC from MDS, indicating file truncation.
2518 *
2519 * caller hold s_mutex.
2520 */
2521static void handle_cap_trunc(struct inode *inode,
2522 struct ceph_mds_caps *trunc,
2523 struct ceph_mds_session *session)
2524 __releases(inode->i_lock)
2525{
2526 struct ceph_inode_info *ci = ceph_inode(inode);
2527 int mds = session->s_mds;
2528 int seq = le32_to_cpu(trunc->seq);
2529 u32 truncate_seq = le32_to_cpu(trunc->truncate_seq);
2530 u64 truncate_size = le64_to_cpu(trunc->truncate_size);
2531 u64 size = le64_to_cpu(trunc->size);
2532 int implemented = 0;
2533 int dirty = __ceph_caps_dirty(ci);
2534 int issued = __ceph_caps_issued(ceph_inode(inode), &implemented);
2535 int queue_trunc = 0;
2536
2537 issued |= implemented | dirty;
2538
2539 dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",
2540 inode, mds, seq, truncate_size, truncate_seq);
2541 queue_trunc = ceph_fill_file_size(inode, issued,
2542 truncate_seq, truncate_size, size);
2543 spin_unlock(&inode->i_lock);
2544
2545 if (queue_trunc)
3c6f6b79 2546 ceph_queue_vmtruncate(inode);
a8599bd8
SW
2547}
2548
2549/*
2550 * Handle EXPORT from MDS. Cap is being migrated _from_ this mds to a
2551 * different one. If we are the most recent migration we've seen (as
2552 * indicated by mseq), make note of the migrating cap bits for the
2553 * duration (until we see the corresponding IMPORT).
2554 *
2555 * caller holds s_mutex
2556 */
2557static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
2558 struct ceph_mds_session *session)
2559{
2560 struct ceph_inode_info *ci = ceph_inode(inode);
2561 int mds = session->s_mds;
2562 unsigned mseq = le32_to_cpu(ex->migrate_seq);
2563 struct ceph_cap *cap = NULL, *t;
2564 struct rb_node *p;
2565 int remember = 1;
2566
2567 dout("handle_cap_export inode %p ci %p mds%d mseq %d\n",
2568 inode, ci, mds, mseq);
2569
2570 spin_lock(&inode->i_lock);
2571
2572 /* make sure we haven't seen a higher mseq */
2573 for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) {
2574 t = rb_entry(p, struct ceph_cap, ci_node);
2575 if (ceph_seq_cmp(t->mseq, mseq) > 0) {
2576 dout(" higher mseq on cap from mds%d\n",
2577 t->session->s_mds);
2578 remember = 0;
2579 }
2580 if (t->session->s_mds == mds)
2581 cap = t;
2582 }
2583
2584 if (cap) {
2585 if (remember) {
2586 /* make note */
2587 ci->i_cap_exporting_mds = mds;
2588 ci->i_cap_exporting_mseq = mseq;
2589 ci->i_cap_exporting_issued = cap->issued;
2590 }
7c1332b8 2591 __ceph_remove_cap(cap);
a8599bd8 2592 }
4ea0043a 2593 /* else, we already released it */
a8599bd8
SW
2594
2595 spin_unlock(&inode->i_lock);
2596}
2597
2598/*
2599 * Handle cap IMPORT. If there are temp bits from an older EXPORT,
2600 * clean them up.
2601 *
2602 * caller holds s_mutex.
2603 */
2604static void handle_cap_import(struct ceph_mds_client *mdsc,
2605 struct inode *inode, struct ceph_mds_caps *im,
2606 struct ceph_mds_session *session,
2607 void *snaptrace, int snaptrace_len)
2608{
2609 struct ceph_inode_info *ci = ceph_inode(inode);
2610 int mds = session->s_mds;
2611 unsigned issued = le32_to_cpu(im->caps);
2612 unsigned wanted = le32_to_cpu(im->wanted);
2613 unsigned seq = le32_to_cpu(im->seq);
2614 unsigned mseq = le32_to_cpu(im->migrate_seq);
2615 u64 realmino = le64_to_cpu(im->realm);
2616 u64 cap_id = le64_to_cpu(im->cap_id);
2617
2618 if (ci->i_cap_exporting_mds >= 0 &&
2619 ceph_seq_cmp(ci->i_cap_exporting_mseq, mseq) < 0) {
2620 dout("handle_cap_import inode %p ci %p mds%d mseq %d"
2621 " - cleared exporting from mds%d\n",
2622 inode, ci, mds, mseq,
2623 ci->i_cap_exporting_mds);
2624 ci->i_cap_exporting_issued = 0;
2625 ci->i_cap_exporting_mseq = 0;
2626 ci->i_cap_exporting_mds = -1;
2627 } else {
2628 dout("handle_cap_import inode %p ci %p mds%d mseq %d\n",
2629 inode, ci, mds, mseq);
2630 }
2631
2632 down_write(&mdsc->snap_rwsem);
2633 ceph_update_snap_trace(mdsc, snaptrace, snaptrace+snaptrace_len,
2634 false);
2635 downgrade_write(&mdsc->snap_rwsem);
2636 ceph_add_cap(inode, session, cap_id, -1,
2637 issued, wanted, seq, mseq, realmino, CEPH_CAP_FLAG_AUTH,
2638 NULL /* no caps context */);
2639 try_flush_caps(inode, session, NULL);
2640 up_read(&mdsc->snap_rwsem);
2641}
2642
2643/*
2644 * Handle a caps message from the MDS.
2645 *
2646 * Identify the appropriate session, inode, and call the right handler
2647 * based on the cap op.
2648 */
2649void ceph_handle_caps(struct ceph_mds_session *session,
2650 struct ceph_msg *msg)
2651{
2652 struct ceph_mds_client *mdsc = session->s_mdsc;
2653 struct super_block *sb = mdsc->client->sb;
2654 struct inode *inode;
2655 struct ceph_cap *cap;
2656 struct ceph_mds_caps *h;
2600d2dd 2657 int mds = session->s_mds;
a8599bd8
SW
2658 int op;
2659 u32 seq;
2660 struct ceph_vino vino;
2661 u64 cap_id;
2662 u64 size, max_size;
6df058c0 2663 u64 tid;
70edb55b 2664 void *snaptrace;
a8599bd8
SW
2665
2666 dout("handle_caps from mds%d\n", mds);
2667
2668 /* decode */
6df058c0 2669 tid = le64_to_cpu(msg->hdr.tid);
a8599bd8
SW
2670 if (msg->front.iov_len < sizeof(*h))
2671 goto bad;
2672 h = msg->front.iov_base;
70edb55b 2673 snaptrace = h + 1;
a8599bd8
SW
2674 op = le32_to_cpu(h->op);
2675 vino.ino = le64_to_cpu(h->ino);
2676 vino.snap = CEPH_NOSNAP;
2677 cap_id = le64_to_cpu(h->cap_id);
2678 seq = le32_to_cpu(h->seq);
2679 size = le64_to_cpu(h->size);
2680 max_size = le64_to_cpu(h->max_size);
2681
2682 mutex_lock(&session->s_mutex);
2683 session->s_seq++;
2684 dout(" mds%d seq %lld cap seq %u\n", session->s_mds, session->s_seq,
2685 (unsigned)seq);
2686
2687 /* lookup ino */
2688 inode = ceph_find_inode(sb, vino);
2689 dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
2690 vino.snap, inode);
2691 if (!inode) {
2692 dout(" i don't have ino %llx\n", vino.ino);
2693 goto done;
2694 }
2695
2696 /* these will work even if we don't have a cap yet */
2697 switch (op) {
2698 case CEPH_CAP_OP_FLUSHSNAP_ACK:
6df058c0 2699 handle_cap_flushsnap_ack(inode, tid, h, session);
a8599bd8
SW
2700 goto done;
2701
2702 case CEPH_CAP_OP_EXPORT:
2703 handle_cap_export(inode, h, session);
2704 goto done;
2705
2706 case CEPH_CAP_OP_IMPORT:
2707 handle_cap_import(mdsc, inode, h, session,
70edb55b 2708 snaptrace, le32_to_cpu(h->snap_trace_len));
15637c8b
SW
2709 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_NODELAY,
2710 session);
2711 goto done_unlocked;
a8599bd8
SW
2712 }
2713
2714 /* the rest require a cap */
2715 spin_lock(&inode->i_lock);
2716 cap = __get_cap_for_mds(ceph_inode(inode), mds);
2717 if (!cap) {
2718 dout("no cap on %p ino %llx.%llx from mds%d, releasing\n",
2719 inode, ceph_ino(inode), ceph_snap(inode), mds);
2720 spin_unlock(&inode->i_lock);
2721 goto done;
2722 }
2723
2724 /* note that each of these drops i_lock for us */
2725 switch (op) {
2726 case CEPH_CAP_OP_REVOKE:
2727 case CEPH_CAP_OP_GRANT:
15637c8b
SW
2728 handle_cap_grant(inode, h, session, cap, msg->middle);
2729 goto done_unlocked;
a8599bd8
SW
2730
2731 case CEPH_CAP_OP_FLUSH_ACK:
6df058c0 2732 handle_cap_flush_ack(inode, tid, h, session, cap);
a8599bd8
SW
2733 break;
2734
2735 case CEPH_CAP_OP_TRUNC:
2736 handle_cap_trunc(inode, h, session);
2737 break;
2738
2739 default:
2740 spin_unlock(&inode->i_lock);
2741 pr_err("ceph_handle_caps: unknown cap op %d %s\n", op,
2742 ceph_cap_op_name(op));
2743 }
2744
2745done:
15637c8b
SW
2746 mutex_unlock(&session->s_mutex);
2747done_unlocked:
a8599bd8
SW
2748 if (inode)
2749 iput(inode);
2750 return;
2751
2752bad:
2753 pr_err("ceph_handle_caps: corrupt message\n");
9ec7cab1 2754 ceph_msg_dump(msg);
a8599bd8
SW
2755 return;
2756}
2757
2758/*
2759 * Delayed work handler to process end of delayed cap release LRU list.
2760 */
afcdaea3 2761void ceph_check_delayed_caps(struct ceph_mds_client *mdsc)
a8599bd8
SW
2762{
2763 struct ceph_inode_info *ci;
2764 int flags = CHECK_CAPS_NODELAY;
2765
a8599bd8
SW
2766 dout("check_delayed_caps\n");
2767 while (1) {
2768 spin_lock(&mdsc->cap_delay_lock);
2769 if (list_empty(&mdsc->cap_delay_list))
2770 break;
2771 ci = list_first_entry(&mdsc->cap_delay_list,
2772 struct ceph_inode_info,
2773 i_cap_delay_list);
2774 if ((ci->i_ceph_flags & CEPH_I_FLUSH) == 0 &&
2775 time_before(jiffies, ci->i_hold_caps_max))
2776 break;
2777 list_del_init(&ci->i_cap_delay_list);
2778 spin_unlock(&mdsc->cap_delay_lock);
2779 dout("check_delayed_caps on %p\n", &ci->vfs_inode);
2780 ceph_check_caps(ci, flags, NULL);
2781 }
2782 spin_unlock(&mdsc->cap_delay_lock);
2783}
2784
afcdaea3
SW
2785/*
2786 * Flush all dirty caps to the mds
2787 */
2788void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
2789{
e9964c10
SW
2790 struct ceph_inode_info *ci, *nci = NULL;
2791 struct inode *inode, *ninode = NULL;
2792 struct list_head *p, *n;
afcdaea3
SW
2793
2794 dout("flush_dirty_caps\n");
2795 spin_lock(&mdsc->cap_dirty_lock);
e9964c10
SW
2796 list_for_each_safe(p, n, &mdsc->cap_dirty) {
2797 if (nci) {
2798 ci = nci;
2799 inode = ninode;
2800 ci->i_ceph_flags &= ~CEPH_I_NOFLUSH;
2801 dout("flush_dirty_caps inode %p (was next inode)\n",
2802 inode);
2803 } else {
2804 ci = list_entry(p, struct ceph_inode_info,
2805 i_dirty_item);
2806 inode = igrab(&ci->vfs_inode);
2807 BUG_ON(!inode);
2808 dout("flush_dirty_caps inode %p\n", inode);
2809 }
2810 if (n != &mdsc->cap_dirty) {
2811 nci = list_entry(n, struct ceph_inode_info,
2812 i_dirty_item);
2813 ninode = igrab(&nci->vfs_inode);
2814 BUG_ON(!ninode);
2815 nci->i_ceph_flags |= CEPH_I_NOFLUSH;
2816 dout("flush_dirty_caps next inode %p, noflush\n",
2817 ninode);
2818 } else {
2819 nci = NULL;
2820 ninode = NULL;
2821 }
afcdaea3
SW
2822 spin_unlock(&mdsc->cap_dirty_lock);
2823 if (inode) {
2824 ceph_check_caps(ci, CHECK_CAPS_NODELAY|CHECK_CAPS_FLUSH,
2825 NULL);
2826 iput(inode);
2827 }
2828 spin_lock(&mdsc->cap_dirty_lock);
2829 }
2830 spin_unlock(&mdsc->cap_dirty_lock);
2831}
2832
a8599bd8
SW
2833/*
2834 * Drop open file reference. If we were the last open file,
2835 * we may need to release capabilities to the MDS (or schedule
2836 * their delayed release).
2837 */
2838void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
2839{
2840 struct inode *inode = &ci->vfs_inode;
2841 int last = 0;
2842
2843 spin_lock(&inode->i_lock);
2844 dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
2845 ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
2846 BUG_ON(ci->i_nr_by_mode[fmode] == 0);
2847 if (--ci->i_nr_by_mode[fmode] == 0)
2848 last++;
2849 spin_unlock(&inode->i_lock);
2850
2851 if (last && ci->i_vino.snap == CEPH_NOSNAP)
2852 ceph_check_caps(ci, 0, NULL);
2853}
2854
2855/*
2856 * Helpers for embedding cap and dentry lease releases into mds
2857 * requests.
2858 *
2859 * @force is used by dentry_release (below) to force inclusion of a
2860 * record for the directory inode, even when there aren't any caps to
2861 * drop.
2862 */
2863int ceph_encode_inode_release(void **p, struct inode *inode,
2864 int mds, int drop, int unless, int force)
2865{
2866 struct ceph_inode_info *ci = ceph_inode(inode);
2867 struct ceph_cap *cap;
2868 struct ceph_mds_request_release *rel = *p;
2869 int ret = 0;
916623da 2870 int used = 0;
a8599bd8
SW
2871
2872 spin_lock(&inode->i_lock);
916623da
SW
2873 used = __ceph_caps_used(ci);
2874
2875 dout("encode_inode_release %p mds%d used %s drop %s unless %s\n", inode,
2876 mds, ceph_cap_string(used), ceph_cap_string(drop),
2877 ceph_cap_string(unless));
2878
2879 /* only drop unused caps */
2880 drop &= ~used;
2881
a8599bd8
SW
2882 cap = __get_cap_for_mds(ci, mds);
2883 if (cap && __cap_is_valid(cap)) {
2884 if (force ||
2885 ((cap->issued & drop) &&
2886 (cap->issued & unless) == 0)) {
2887 if ((cap->issued & drop) &&
2888 (cap->issued & unless) == 0) {
2889 dout("encode_inode_release %p cap %p %s -> "
2890 "%s\n", inode, cap,
2891 ceph_cap_string(cap->issued),
2892 ceph_cap_string(cap->issued & ~drop));
2893 cap->issued &= ~drop;
2894 cap->implemented &= ~drop;
2895 if (ci->i_ceph_flags & CEPH_I_NODELAY) {
2896 int wanted = __ceph_caps_wanted(ci);
2897 dout(" wanted %s -> %s (act %s)\n",
2898 ceph_cap_string(cap->mds_wanted),
2899 ceph_cap_string(cap->mds_wanted &
2900 ~wanted),
2901 ceph_cap_string(wanted));
2902 cap->mds_wanted &= wanted;
2903 }
2904 } else {
2905 dout("encode_inode_release %p cap %p %s"
2906 " (force)\n", inode, cap,
2907 ceph_cap_string(cap->issued));
2908 }
2909
2910 rel->ino = cpu_to_le64(ceph_ino(inode));
2911 rel->cap_id = cpu_to_le64(cap->cap_id);
2912 rel->seq = cpu_to_le32(cap->seq);
2913 rel->issue_seq = cpu_to_le32(cap->issue_seq),
2914 rel->mseq = cpu_to_le32(cap->mseq);
2915 rel->caps = cpu_to_le32(cap->issued);
2916 rel->wanted = cpu_to_le32(cap->mds_wanted);
2917 rel->dname_len = 0;
2918 rel->dname_seq = 0;
2919 *p += sizeof(*rel);
2920 ret = 1;
2921 } else {
2922 dout("encode_inode_release %p cap %p %s\n",
2923 inode, cap, ceph_cap_string(cap->issued));
2924 }
2925 }
2926 spin_unlock(&inode->i_lock);
2927 return ret;
2928}
2929
2930int ceph_encode_dentry_release(void **p, struct dentry *dentry,
2931 int mds, int drop, int unless)
2932{
2933 struct inode *dir = dentry->d_parent->d_inode;
2934 struct ceph_mds_request_release *rel = *p;
2935 struct ceph_dentry_info *di = ceph_dentry(dentry);
2936 int force = 0;
2937 int ret;
2938
2939 /*
2940 * force an record for the directory caps if we have a dentry lease.
2941 * this is racy (can't take i_lock and d_lock together), but it
2942 * doesn't have to be perfect; the mds will revoke anything we don't
2943 * release.
2944 */
2945 spin_lock(&dentry->d_lock);
2946 if (di->lease_session && di->lease_session->s_mds == mds)
2947 force = 1;
2948 spin_unlock(&dentry->d_lock);
2949
2950 ret = ceph_encode_inode_release(p, dir, mds, drop, unless, force);
2951
2952 spin_lock(&dentry->d_lock);
2953 if (ret && di->lease_session && di->lease_session->s_mds == mds) {
2954 dout("encode_dentry_release %p mds%d seq %d\n",
2955 dentry, mds, (int)di->lease_seq);
2956 rel->dname_len = cpu_to_le32(dentry->d_name.len);
2957 memcpy(*p, dentry->d_name.name, dentry->d_name.len);
2958 *p += dentry->d_name.len;
2959 rel->dname_seq = cpu_to_le32(di->lease_seq);
2960 }
2961 spin_unlock(&dentry->d_lock);
2962 return ret;
2963}