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Linux 3.16-rc2
[linux/fpc-iii.git] / fs / ceph / mds_client.c
blob92a2548278fca0c52609d120db33cf070db621c6
1 #include <linux/ceph/ceph_debug.h>
2
3 #include <linux/fs.h>
4 #include <linux/wait.h>
5 #include <linux/slab.h>
6 #include <linux/gfp.h>
7 #include <linux/sched.h>
8 #include <linux/debugfs.h>
9 #include <linux/seq_file.h>
10
11 #include "super.h"
12 #include "mds_client.h"
13
14 #include <linux/ceph/ceph_features.h>
15 #include <linux/ceph/messenger.h>
16 #include <linux/ceph/decode.h>
17 #include <linux/ceph/pagelist.h>
18 #include <linux/ceph/auth.h>
19 #include <linux/ceph/debugfs.h>
20
21 /*
22 * A cluster of MDS (metadata server) daemons is responsible for
23 * managing the file system namespace (the directory hierarchy and
24 * inodes) and for coordinating shared access to storage. Metadata is
25 * partitioning hierarchically across a number of servers, and that
26 * partition varies over time as the cluster adjusts the distribution
27 * in order to balance load.
28 *
29 * The MDS client is primarily responsible to managing synchronous
30 * metadata requests for operations like open, unlink, and so forth.
31 * If there is a MDS failure, we find out about it when we (possibly
32 * request and) receive a new MDS map, and can resubmit affected
33 * requests.
34 *
35 * For the most part, though, we take advantage of a lossless
36 * communications channel to the MDS, and do not need to worry about
37 * timing out or resubmitting requests.
38 *
39 * We maintain a stateful "session" with each MDS we interact with.
40 * Within each session, we sent periodic heartbeat messages to ensure
41 * any capabilities or leases we have been issues remain valid. If
42 * the session times out and goes stale, our leases and capabilities
43 * are no longer valid.
44 */
45
46 struct ceph_reconnect_state {
47 int nr_caps;
48 struct ceph_pagelist *pagelist;
49 bool flock;
50 };
51
52 static void __wake_requests(struct ceph_mds_client *mdsc,
53 struct list_head *head);
54
55 static const struct ceph_connection_operations mds_con_ops;
56
57
58 /*
59 * mds reply parsing
60 */
61
62 /*
63 * parse individual inode info
64 */
65 static int parse_reply_info_in(void **p, void *end,
66 struct ceph_mds_reply_info_in *info,
67 u64 features)
68 {
69 int err = -EIO;
70
71 info->in = *p;
72 *p += sizeof(struct ceph_mds_reply_inode) +
73 sizeof(*info->in->fragtree.splits) *
74 le32_to_cpu(info->in->fragtree.nsplits);
75
76 ceph_decode_32_safe(p, end, info->symlink_len, bad);
77 ceph_decode_need(p, end, info->symlink_len, bad);
78 info->symlink = *p;
79 *p += info->symlink_len;
80
81 if (features & CEPH_FEATURE_DIRLAYOUTHASH)
82 ceph_decode_copy_safe(p, end, &info->dir_layout,
83 sizeof(info->dir_layout), bad);
84 else
85 memset(&info->dir_layout, 0, sizeof(info->dir_layout));
86
87 ceph_decode_32_safe(p, end, info->xattr_len, bad);
88 ceph_decode_need(p, end, info->xattr_len, bad);
89 info->xattr_data = *p;
90 *p += info->xattr_len;
91 return 0;
92 bad:
93 return err;
94 }
95
96 /*
97 * parse a normal reply, which may contain a (dir+)dentry and/or a
98 * target inode.
99 */
100 static int parse_reply_info_trace(void **p, void *end,
101 struct ceph_mds_reply_info_parsed *info,
102 u64 features)
103 {
104 int err;
105
106 if (info->head->is_dentry) {
107 err = parse_reply_info_in(p, end, &info->diri, features);
108 if (err < 0)
109 goto out_bad;
110
111 if (unlikely(*p + sizeof(*info->dirfrag) > end))
112 goto bad;
113 info->dirfrag = *p;
114 *p += sizeof(*info->dirfrag) +
115 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
116 if (unlikely(*p > end))
117 goto bad;
118
119 ceph_decode_32_safe(p, end, info->dname_len, bad);
120 ceph_decode_need(p, end, info->dname_len, bad);
121 info->dname = *p;
122 *p += info->dname_len;
123 info->dlease = *p;
124 *p += sizeof(*info->dlease);
125 }
126
127 if (info->head->is_target) {
128 err = parse_reply_info_in(p, end, &info->targeti, features);
129 if (err < 0)
130 goto out_bad;
131 }
132
133 if (unlikely(*p != end))
134 goto bad;
135 return 0;
136
137 bad:
138 err = -EIO;
139 out_bad:
140 pr_err("problem parsing mds trace %d\n", err);
141 return err;
142 }
143
144 /*
145 * parse readdir results
146 */
147 static int parse_reply_info_dir(void **p, void *end,
148 struct ceph_mds_reply_info_parsed *info,
149 u64 features)
150 {
151 u32 num, i = 0;
152 int err;
153
154 info->dir_dir = *p;
155 if (*p + sizeof(*info->dir_dir) > end)
156 goto bad;
157 *p += sizeof(*info->dir_dir) +
158 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
159 if (*p > end)
160 goto bad;
161
162 ceph_decode_need(p, end, sizeof(num) + 2, bad);
163 num = ceph_decode_32(p);
164 info->dir_end = ceph_decode_8(p);
165 info->dir_complete = ceph_decode_8(p);
166 if (num == 0)
167 goto done;
168
169 BUG_ON(!info->dir_in);
170 info->dir_dname = (void *)(info->dir_in + num);
171 info->dir_dname_len = (void *)(info->dir_dname + num);
172 info->dir_dlease = (void *)(info->dir_dname_len + num);
173 if ((unsigned long)(info->dir_dlease + num) >
174 (unsigned long)info->dir_in + info->dir_buf_size) {
175 pr_err("dir contents are larger than expected\n");
176 WARN_ON(1);
177 goto bad;
178 }
179
180 info->dir_nr = num;
181 while (num) {
182 /* dentry */
183 ceph_decode_need(p, end, sizeof(u32)*2, bad);
184 info->dir_dname_len[i] = ceph_decode_32(p);
185 ceph_decode_need(p, end, info->dir_dname_len[i], bad);
186 info->dir_dname[i] = *p;
187 *p += info->dir_dname_len[i];
188 dout("parsed dir dname '%.*s'\n", info->dir_dname_len[i],
189 info->dir_dname[i]);
190 info->dir_dlease[i] = *p;
191 *p += sizeof(struct ceph_mds_reply_lease);
192
193 /* inode */
194 err = parse_reply_info_in(p, end, &info->dir_in[i], features);
195 if (err < 0)
196 goto out_bad;
197 i++;
198 num--;
199 }
200
201 done:
202 if (*p != end)
203 goto bad;
204 return 0;
205
206 bad:
207 err = -EIO;
208 out_bad:
209 pr_err("problem parsing dir contents %d\n", err);
210 return err;
211 }
212
213 /*
214 * parse fcntl F_GETLK results
215 */
216 static int parse_reply_info_filelock(void **p, void *end,
217 struct ceph_mds_reply_info_parsed *info,
218 u64 features)
219 {
220 if (*p + sizeof(*info->filelock_reply) > end)
221 goto bad;
222
223 info->filelock_reply = *p;
224 *p += sizeof(*info->filelock_reply);
225
226 if (unlikely(*p != end))
227 goto bad;
228 return 0;
229
230 bad:
231 return -EIO;
232 }
233
234 /*
235 * parse create results
236 */
237 static int parse_reply_info_create(void **p, void *end,
238 struct ceph_mds_reply_info_parsed *info,
239 u64 features)
240 {
241 if (features & CEPH_FEATURE_REPLY_CREATE_INODE) {
242 if (*p == end) {
243 info->has_create_ino = false;
244 } else {
245 info->has_create_ino = true;
246 info->ino = ceph_decode_64(p);
247 }
248 }
249
250 if (unlikely(*p != end))
251 goto bad;
252 return 0;
253
254 bad:
255 return -EIO;
256 }
257
258 /*
259 * parse extra results
260 */
261 static int parse_reply_info_extra(void **p, void *end,
262 struct ceph_mds_reply_info_parsed *info,
263 u64 features)
264 {
265 if (info->head->op == CEPH_MDS_OP_GETFILELOCK)
266 return parse_reply_info_filelock(p, end, info, features);
267 else if (info->head->op == CEPH_MDS_OP_READDIR ||
268 info->head->op == CEPH_MDS_OP_LSSNAP)
269 return parse_reply_info_dir(p, end, info, features);
270 else if (info->head->op == CEPH_MDS_OP_CREATE)
271 return parse_reply_info_create(p, end, info, features);
272 else
273 return -EIO;
274 }
275
276 /*
277 * parse entire mds reply
278 */
279 static int parse_reply_info(struct ceph_msg *msg,
280 struct ceph_mds_reply_info_parsed *info,
281 u64 features)
282 {
283 void *p, *end;
284 u32 len;
285 int err;
286
287 info->head = msg->front.iov_base;
288 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
289 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
290
291 /* trace */
292 ceph_decode_32_safe(&p, end, len, bad);
293 if (len > 0) {
294 ceph_decode_need(&p, end, len, bad);
295 err = parse_reply_info_trace(&p, p+len, info, features);
296 if (err < 0)
297 goto out_bad;
298 }
299
300 /* extra */
301 ceph_decode_32_safe(&p, end, len, bad);
302 if (len > 0) {
303 ceph_decode_need(&p, end, len, bad);
304 err = parse_reply_info_extra(&p, p+len, info, features);
305 if (err < 0)
306 goto out_bad;
307 }
308
309 /* snap blob */
310 ceph_decode_32_safe(&p, end, len, bad);
311 info->snapblob_len = len;
312 info->snapblob = p;
313 p += len;
314
315 if (p != end)
316 goto bad;
317 return 0;
318
319 bad:
320 err = -EIO;
321 out_bad:
322 pr_err("mds parse_reply err %d\n", err);
323 return err;
324 }
325
326 static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
327 {
328 if (!info->dir_in)
329 return;
330 free_pages((unsigned long)info->dir_in, get_order(info->dir_buf_size));
331 }
332
333
334 /*
335 * sessions
336 */
337 static const char *session_state_name(int s)
338 {
339 switch (s) {
340 case CEPH_MDS_SESSION_NEW: return "new";
341 case CEPH_MDS_SESSION_OPENING: return "opening";
342 case CEPH_MDS_SESSION_OPEN: return "open";
343 case CEPH_MDS_SESSION_HUNG: return "hung";
344 case CEPH_MDS_SESSION_CLOSING: return "closing";
345 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
346 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
347 default: return "???";
348 }
349 }
350
351 static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
352 {
353 if (atomic_inc_not_zero(&s->s_ref)) {
354 dout("mdsc get_session %p %d -> %d\n", s,
355 atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
356 return s;
357 } else {
358 dout("mdsc get_session %p 0 -- FAIL", s);
359 return NULL;
360 }
361 }
362
363 void ceph_put_mds_session(struct ceph_mds_session *s)
364 {
365 dout("mdsc put_session %p %d -> %d\n", s,
366 atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
367 if (atomic_dec_and_test(&s->s_ref)) {
368 if (s->s_auth.authorizer)
369 ceph_auth_destroy_authorizer(
370 s->s_mdsc->fsc->client->monc.auth,
371 s->s_auth.authorizer);
372 kfree(s);
373 }
374 }
375
376 /*
377 * called under mdsc->mutex
378 */
379 struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
380 int mds)
381 {
382 struct ceph_mds_session *session;
383
384 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
385 return NULL;
386 session = mdsc->sessions[mds];
387 dout("lookup_mds_session %p %d\n", session,
388 atomic_read(&session->s_ref));
389 get_session(session);
390 return session;
391 }
392
393 static bool __have_session(struct ceph_mds_client *mdsc, int mds)
394 {
395 if (mds >= mdsc->max_sessions)
396 return false;
397 return mdsc->sessions[mds];
398 }
399
400 static int __verify_registered_session(struct ceph_mds_client *mdsc,
401 struct ceph_mds_session *s)
402 {
403 if (s->s_mds >= mdsc->max_sessions ||
404 mdsc->sessions[s->s_mds] != s)
405 return -ENOENT;
406 return 0;
407 }
408
409 /*
410 * create+register a new session for given mds.
411 * called under mdsc->mutex.
412 */
413 static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
414 int mds)
415 {
416 struct ceph_mds_session *s;
417
418 if (mds >= mdsc->mdsmap->m_max_mds)
419 return ERR_PTR(-EINVAL);
420
421 s = kzalloc(sizeof(*s), GFP_NOFS);
422 if (!s)
423 return ERR_PTR(-ENOMEM);
424 s->s_mdsc = mdsc;
425 s->s_mds = mds;
426 s->s_state = CEPH_MDS_SESSION_NEW;
427 s->s_ttl = 0;
428 s->s_seq = 0;
429 mutex_init(&s->s_mutex);
430
431 ceph_con_init(&s->s_con, s, &mds_con_ops, &mdsc->fsc->client->msgr);
432
433 spin_lock_init(&s->s_gen_ttl_lock);
434 s->s_cap_gen = 0;
435 s->s_cap_ttl = jiffies - 1;
436
437 spin_lock_init(&s->s_cap_lock);
438 s->s_renew_requested = 0;
439 s->s_renew_seq = 0;
440 INIT_LIST_HEAD(&s->s_caps);
441 s->s_nr_caps = 0;
442 s->s_trim_caps = 0;
443 atomic_set(&s->s_ref, 1);
444 INIT_LIST_HEAD(&s->s_waiting);
445 INIT_LIST_HEAD(&s->s_unsafe);
446 s->s_num_cap_releases = 0;
447 s->s_cap_reconnect = 0;
448 s->s_cap_iterator = NULL;
449 INIT_LIST_HEAD(&s->s_cap_releases);
450 INIT_LIST_HEAD(&s->s_cap_releases_done);
451 INIT_LIST_HEAD(&s->s_cap_flushing);
452 INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
453
454 dout("register_session mds%d\n", mds);
455 if (mds >= mdsc->max_sessions) {
456 int newmax = 1 << get_count_order(mds+1);
457 struct ceph_mds_session **sa;
458
459 dout("register_session realloc to %d\n", newmax);
460 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
461 if (sa == NULL)
462 goto fail_realloc;
463 if (mdsc->sessions) {
464 memcpy(sa, mdsc->sessions,
465 mdsc->max_sessions * sizeof(void *));
466 kfree(mdsc->sessions);
467 }
468 mdsc->sessions = sa;
469 mdsc->max_sessions = newmax;
470 }
471 mdsc->sessions[mds] = s;
472 atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
473
474 ceph_con_open(&s->s_con, CEPH_ENTITY_TYPE_MDS, mds,
475 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
476
477 return s;
478
479 fail_realloc:
480 kfree(s);
481 return ERR_PTR(-ENOMEM);
482 }
483
484 /*
485 * called under mdsc->mutex
486 */
487 static void __unregister_session(struct ceph_mds_client *mdsc,
488 struct ceph_mds_session *s)
489 {
490 dout("__unregister_session mds%d %p\n", s->s_mds, s);
491 BUG_ON(mdsc->sessions[s->s_mds] != s);
492 mdsc->sessions[s->s_mds] = NULL;
493 ceph_con_close(&s->s_con);
494 ceph_put_mds_session(s);
495 }
496
497 /*
498 * drop session refs in request.
499 *
500 * should be last request ref, or hold mdsc->mutex
501 */
502 static void put_request_session(struct ceph_mds_request *req)
503 {
504 if (req->r_session) {
505 ceph_put_mds_session(req->r_session);
506 req->r_session = NULL;
507 }
508 }
509
510 void ceph_mdsc_release_request(struct kref *kref)
511 {
512 struct ceph_mds_request *req = container_of(kref,
513 struct ceph_mds_request,
514 r_kref);
515 destroy_reply_info(&req->r_reply_info);
516 if (req->r_request)
517 ceph_msg_put(req->r_request);
518 if (req->r_reply)
519 ceph_msg_put(req->r_reply);
520 if (req->r_inode) {
521 ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
522 iput(req->r_inode);
523 }
524 if (req->r_locked_dir)
525 ceph_put_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
526 if (req->r_target_inode)
527 iput(req->r_target_inode);
528 if (req->r_dentry)
529 dput(req->r_dentry);
530 if (req->r_old_dentry)
531 dput(req->r_old_dentry);
532 if (req->r_old_dentry_dir) {
533 /*
534 * track (and drop pins for) r_old_dentry_dir
535 * separately, since r_old_dentry's d_parent may have
536 * changed between the dir mutex being dropped and
537 * this request being freed.
538 */
539 ceph_put_cap_refs(ceph_inode(req->r_old_dentry_dir),
540 CEPH_CAP_PIN);
541 iput(req->r_old_dentry_dir);
542 }
543 kfree(req->r_path1);
544 kfree(req->r_path2);
545 put_request_session(req);
546 ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation);
547 kfree(req);
548 }
549
550 /*
551 * lookup session, bump ref if found.
552 *
553 * called under mdsc->mutex.
554 */
555 static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
556 u64 tid)
557 {
558 struct ceph_mds_request *req;
559 struct rb_node *n = mdsc->request_tree.rb_node;
560
561 while (n) {
562 req = rb_entry(n, struct ceph_mds_request, r_node);
563 if (tid < req->r_tid)
564 n = n->rb_left;
565 else if (tid > req->r_tid)
566 n = n->rb_right;
567 else {
568 ceph_mdsc_get_request(req);
569 return req;
570 }
571 }
572 return NULL;
573 }
574
575 static void __insert_request(struct ceph_mds_client *mdsc,
576 struct ceph_mds_request *new)
577 {
578 struct rb_node **p = &mdsc->request_tree.rb_node;
579 struct rb_node *parent = NULL;
580 struct ceph_mds_request *req = NULL;
581
582 while (*p) {
583 parent = *p;
584 req = rb_entry(parent, struct ceph_mds_request, r_node);
585 if (new->r_tid < req->r_tid)
586 p = &(*p)->rb_left;
587 else if (new->r_tid > req->r_tid)
588 p = &(*p)->rb_right;
589 else
590 BUG();
591 }
592
593 rb_link_node(&new->r_node, parent, p);
594 rb_insert_color(&new->r_node, &mdsc->request_tree);
595 }
596
597 /*
598 * Register an in-flight request, and assign a tid. Link to directory
599 * are modifying (if any).
600 *
601 * Called under mdsc->mutex.
602 */
603 static void __register_request(struct ceph_mds_client *mdsc,
604 struct ceph_mds_request *req,
605 struct inode *dir)
606 {
607 req->r_tid = ++mdsc->last_tid;
608 if (req->r_num_caps)
609 ceph_reserve_caps(mdsc, &req->r_caps_reservation,
610 req->r_num_caps);
611 dout("__register_request %p tid %lld\n", req, req->r_tid);
612 ceph_mdsc_get_request(req);
613 __insert_request(mdsc, req);
614
615 req->r_uid = current_fsuid();
616 req->r_gid = current_fsgid();
617
618 if (dir) {
619 struct ceph_inode_info *ci = ceph_inode(dir);
620
621 ihold(dir);
622 spin_lock(&ci->i_unsafe_lock);
623 req->r_unsafe_dir = dir;
624 list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
625 spin_unlock(&ci->i_unsafe_lock);
626 }
627 }
628
629 static void __unregister_request(struct ceph_mds_client *mdsc,
630 struct ceph_mds_request *req)
631 {
632 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
633 rb_erase(&req->r_node, &mdsc->request_tree);
634 RB_CLEAR_NODE(&req->r_node);
635
636 if (req->r_unsafe_dir) {
637 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
638
639 spin_lock(&ci->i_unsafe_lock);
640 list_del_init(&req->r_unsafe_dir_item);
641 spin_unlock(&ci->i_unsafe_lock);
642
643 iput(req->r_unsafe_dir);
644 req->r_unsafe_dir = NULL;
645 }
646
647 complete_all(&req->r_safe_completion);
648
649 ceph_mdsc_put_request(req);
650 }
651
652 /*
653 * Choose mds to send request to next. If there is a hint set in the
654 * request (e.g., due to a prior forward hint from the mds), use that.
655 * Otherwise, consult frag tree and/or caps to identify the
656 * appropriate mds. If all else fails, choose randomly.
657 *
658 * Called under mdsc->mutex.
659 */
660 static struct dentry *get_nonsnap_parent(struct dentry *dentry)
661 {
662 /*
663 * we don't need to worry about protecting the d_parent access
664 * here because we never renaming inside the snapped namespace
665 * except to resplice to another snapdir, and either the old or new
666 * result is a valid result.
667 */
668 while (!IS_ROOT(dentry) && ceph_snap(dentry->d_inode) != CEPH_NOSNAP)
669 dentry = dentry->d_parent;
670 return dentry;
671 }
672
673 static int __choose_mds(struct ceph_mds_client *mdsc,
674 struct ceph_mds_request *req)
675 {
676 struct inode *inode;
677 struct ceph_inode_info *ci;
678 struct ceph_cap *cap;
679 int mode = req->r_direct_mode;
680 int mds = -1;
681 u32 hash = req->r_direct_hash;
682 bool is_hash = req->r_direct_is_hash;
683
684 /*
685 * is there a specific mds we should try? ignore hint if we have
686 * no session and the mds is not up (active or recovering).
687 */
688 if (req->r_resend_mds >= 0 &&
689 (__have_session(mdsc, req->r_resend_mds) ||
690 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
691 dout("choose_mds using resend_mds mds%d\n",
692 req->r_resend_mds);
693 return req->r_resend_mds;
694 }
695
696 if (mode == USE_RANDOM_MDS)
697 goto random;
698
699 inode = NULL;
700 if (req->r_inode) {
701 inode = req->r_inode;
702 } else if (req->r_dentry) {
703 /* ignore race with rename; old or new d_parent is okay */
704 struct dentry *parent = req->r_dentry->d_parent;
705 struct inode *dir = parent->d_inode;
706
707 if (dir->i_sb != mdsc->fsc->sb) {
708 /* not this fs! */
709 inode = req->r_dentry->d_inode;
710 } else if (ceph_snap(dir) != CEPH_NOSNAP) {
711 /* direct snapped/virtual snapdir requests
712 * based on parent dir inode */
713 struct dentry *dn = get_nonsnap_parent(parent);
714 inode = dn->d_inode;
715 dout("__choose_mds using nonsnap parent %p\n", inode);
716 } else {
717 /* dentry target */
718 inode = req->r_dentry->d_inode;
719 if (!inode || mode == USE_AUTH_MDS) {
720 /* dir + name */
721 inode = dir;
722 hash = ceph_dentry_hash(dir, req->r_dentry);
723 is_hash = true;
724 }
725 }
726 }
727
728 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
729 (int)hash, mode);
730 if (!inode)
731 goto random;
732 ci = ceph_inode(inode);
733
734 if (is_hash && S_ISDIR(inode->i_mode)) {
735 struct ceph_inode_frag frag;
736 int found;
737
738 ceph_choose_frag(ci, hash, &frag, &found);
739 if (found) {
740 if (mode == USE_ANY_MDS && frag.ndist > 0) {
741 u8 r;
742
743 /* choose a random replica */
744 get_random_bytes(&r, 1);
745 r %= frag.ndist;
746 mds = frag.dist[r];
747 dout("choose_mds %p %llx.%llx "
748 "frag %u mds%d (%d/%d)\n",
749 inode, ceph_vinop(inode),
750 frag.frag, mds,
751 (int)r, frag.ndist);
752 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
753 CEPH_MDS_STATE_ACTIVE)
754 return mds;
755 }
756
757 /* since this file/dir wasn't known to be
758 * replicated, then we want to look for the
759 * authoritative mds. */
760 mode = USE_AUTH_MDS;
761 if (frag.mds >= 0) {
762 /* choose auth mds */
763 mds = frag.mds;
764 dout("choose_mds %p %llx.%llx "
765 "frag %u mds%d (auth)\n",
766 inode, ceph_vinop(inode), frag.frag, mds);
767 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
768 CEPH_MDS_STATE_ACTIVE)
769 return mds;
770 }
771 }
772 }
773
774 spin_lock(&ci->i_ceph_lock);
775 cap = NULL;
776 if (mode == USE_AUTH_MDS)
777 cap = ci->i_auth_cap;
778 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
779 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
780 if (!cap) {
781 spin_unlock(&ci->i_ceph_lock);
782 goto random;
783 }
784 mds = cap->session->s_mds;
785 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
786 inode, ceph_vinop(inode), mds,
787 cap == ci->i_auth_cap ? "auth " : "", cap);
788 spin_unlock(&ci->i_ceph_lock);
789 return mds;
790
791 random:
792 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
793 dout("choose_mds chose random mds%d\n", mds);
794 return mds;
795 }
796
797
798 /*
799 * session messages
800 */
801 static struct ceph_msg *create_session_msg(u32 op, u64 seq)
802 {
803 struct ceph_msg *msg;
804 struct ceph_mds_session_head *h;
805
806 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS,
807 false);
808 if (!msg) {
809 pr_err("create_session_msg ENOMEM creating msg\n");
810 return NULL;
811 }
812 h = msg->front.iov_base;
813 h->op = cpu_to_le32(op);
814 h->seq = cpu_to_le64(seq);
815 return msg;
816 }
817
818 /*
819 * send session open request.
820 *
821 * called under mdsc->mutex
822 */
823 static int __open_session(struct ceph_mds_client *mdsc,
824 struct ceph_mds_session *session)
825 {
826 struct ceph_msg *msg;
827 int mstate;
828 int mds = session->s_mds;
829
830 /* wait for mds to go active? */
831 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
832 dout("open_session to mds%d (%s)\n", mds,
833 ceph_mds_state_name(mstate));
834 session->s_state = CEPH_MDS_SESSION_OPENING;
835 session->s_renew_requested = jiffies;
836
837 /* send connect message */
838 msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
839 if (!msg)
840 return -ENOMEM;
841 ceph_con_send(&session->s_con, msg);
842 return 0;
843 }
844
845 /*
846 * open sessions for any export targets for the given mds
847 *
848 * called under mdsc->mutex
849 */
850 static struct ceph_mds_session *
851 __open_export_target_session(struct ceph_mds_client *mdsc, int target)
852 {
853 struct ceph_mds_session *session;
854
855 session = __ceph_lookup_mds_session(mdsc, target);
856 if (!session) {
857 session = register_session(mdsc, target);
858 if (IS_ERR(session))
859 return session;
860 }
861 if (session->s_state == CEPH_MDS_SESSION_NEW ||
862 session->s_state == CEPH_MDS_SESSION_CLOSING)
863 __open_session(mdsc, session);
864
865 return session;
866 }
867
868 struct ceph_mds_session *
869 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target)
870 {
871 struct ceph_mds_session *session;
872
873 dout("open_export_target_session to mds%d\n", target);
874
875 mutex_lock(&mdsc->mutex);
876 session = __open_export_target_session(mdsc, target);
877 mutex_unlock(&mdsc->mutex);
878
879 return session;
880 }
881
882 static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
883 struct ceph_mds_session *session)
884 {
885 struct ceph_mds_info *mi;
886 struct ceph_mds_session *ts;
887 int i, mds = session->s_mds;
888
889 if (mds >= mdsc->mdsmap->m_max_mds)
890 return;
891
892 mi = &mdsc->mdsmap->m_info[mds];
893 dout("open_export_target_sessions for mds%d (%d targets)\n",
894 session->s_mds, mi->num_export_targets);
895
896 for (i = 0; i < mi->num_export_targets; i++) {
897 ts = __open_export_target_session(mdsc, mi->export_targets[i]);
898 if (!IS_ERR(ts))
899 ceph_put_mds_session(ts);
900 }
901 }
902
903 void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
904 struct ceph_mds_session *session)
905 {
906 mutex_lock(&mdsc->mutex);
907 __open_export_target_sessions(mdsc, session);
908 mutex_unlock(&mdsc->mutex);
909 }
910
911 /*
912 * session caps
913 */
914
915 /*
916 * Free preallocated cap messages assigned to this session
917 */
918 static void cleanup_cap_releases(struct ceph_mds_session *session)
919 {
920 struct ceph_msg *msg;
921
922 spin_lock(&session->s_cap_lock);
923 while (!list_empty(&session->s_cap_releases)) {
924 msg = list_first_entry(&session->s_cap_releases,
925 struct ceph_msg, list_head);
926 list_del_init(&msg->list_head);
927 ceph_msg_put(msg);
928 }
929 while (!list_empty(&session->s_cap_releases_done)) {
930 msg = list_first_entry(&session->s_cap_releases_done,
931 struct ceph_msg, list_head);
932 list_del_init(&msg->list_head);
933 ceph_msg_put(msg);
934 }
935 spin_unlock(&session->s_cap_lock);
936 }
937
938 /*
939 * Helper to safely iterate over all caps associated with a session, with
940 * special care taken to handle a racing __ceph_remove_cap().
941 *
942 * Caller must hold session s_mutex.
943 */
944 static int iterate_session_caps(struct ceph_mds_session *session,
945 int (*cb)(struct inode *, struct ceph_cap *,
946 void *), void *arg)
947 {
948 struct list_head *p;
949 struct ceph_cap *cap;
950 struct inode *inode, *last_inode = NULL;
951 struct ceph_cap *old_cap = NULL;
952 int ret;
953
954 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
955 spin_lock(&session->s_cap_lock);
956 p = session->s_caps.next;
957 while (p != &session->s_caps) {
958 cap = list_entry(p, struct ceph_cap, session_caps);
959 inode = igrab(&cap->ci->vfs_inode);
960 if (!inode) {
961 p = p->next;
962 continue;
963 }
964 session->s_cap_iterator = cap;
965 spin_unlock(&session->s_cap_lock);
966
967 if (last_inode) {
968 iput(last_inode);
969 last_inode = NULL;
970 }
971 if (old_cap) {
972 ceph_put_cap(session->s_mdsc, old_cap);
973 old_cap = NULL;
974 }
975
976 ret = cb(inode, cap, arg);
977 last_inode = inode;
978
979 spin_lock(&session->s_cap_lock);
980 p = p->next;
981 if (cap->ci == NULL) {
982 dout("iterate_session_caps finishing cap %p removal\n",
983 cap);
984 BUG_ON(cap->session != session);
985 list_del_init(&cap->session_caps);
986 session->s_nr_caps--;
987 cap->session = NULL;
988 old_cap = cap; /* put_cap it w/o locks held */
989 }
990 if (ret < 0)
991 goto out;
992 }
993 ret = 0;
994 out:
995 session->s_cap_iterator = NULL;
996 spin_unlock(&session->s_cap_lock);
997
998 if (last_inode)
999 iput(last_inode);
1000 if (old_cap)
1001 ceph_put_cap(session->s_mdsc, old_cap);
1002
1003 return ret;
1004 }
1005
1006 static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
1007 void *arg)
1008 {
1009 struct ceph_inode_info *ci = ceph_inode(inode);
1010 int drop = 0;
1011
1012 dout("removing cap %p, ci is %p, inode is %p\n",
1013 cap, ci, &ci->vfs_inode);
1014 spin_lock(&ci->i_ceph_lock);
1015 __ceph_remove_cap(cap, false);
1016 if (!__ceph_is_any_real_caps(ci)) {
1017 struct ceph_mds_client *mdsc =
1018 ceph_sb_to_client(inode->i_sb)->mdsc;
1019
1020 spin_lock(&mdsc->cap_dirty_lock);
1021 if (!list_empty(&ci->i_dirty_item)) {
1022 pr_info(" dropping dirty %s state for %p %lld\n",
1023 ceph_cap_string(ci->i_dirty_caps),
1024 inode, ceph_ino(inode));
1025 ci->i_dirty_caps = 0;
1026 list_del_init(&ci->i_dirty_item);
1027 drop = 1;
1028 }
1029 if (!list_empty(&ci->i_flushing_item)) {
1030 pr_info(" dropping dirty+flushing %s state for %p %lld\n",
1031 ceph_cap_string(ci->i_flushing_caps),
1032 inode, ceph_ino(inode));
1033 ci->i_flushing_caps = 0;
1034 list_del_init(&ci->i_flushing_item);
1035 mdsc->num_cap_flushing--;
1036 drop = 1;
1037 }
1038 if (drop && ci->i_wrbuffer_ref) {
1039 pr_info(" dropping dirty data for %p %lld\n",
1040 inode, ceph_ino(inode));
1041 ci->i_wrbuffer_ref = 0;
1042 ci->i_wrbuffer_ref_head = 0;
1043 drop++;
1044 }
1045 spin_unlock(&mdsc->cap_dirty_lock);
1046 }
1047 spin_unlock(&ci->i_ceph_lock);
1048 while (drop--)
1049 iput(inode);
1050 return 0;
1051 }
1052
1053 /*
1054 * caller must hold session s_mutex
1055 */
1056 static void remove_session_caps(struct ceph_mds_session *session)
1057 {
1058 dout("remove_session_caps on %p\n", session);
1059 iterate_session_caps(session, remove_session_caps_cb, NULL);
1060
1061 spin_lock(&session->s_cap_lock);
1062 if (session->s_nr_caps > 0) {
1063 struct super_block *sb = session->s_mdsc->fsc->sb;
1064 struct inode *inode;
1065 struct ceph_cap *cap, *prev = NULL;
1066 struct ceph_vino vino;
1067 /*
1068 * iterate_session_caps() skips inodes that are being
1069 * deleted, we need to wait until deletions are complete.
1070 * __wait_on_freeing_inode() is designed for the job,
1071 * but it is not exported, so use lookup inode function
1072 * to access it.
1073 */
1074 while (!list_empty(&session->s_caps)) {
1075 cap = list_entry(session->s_caps.next,
1076 struct ceph_cap, session_caps);
1077 if (cap == prev)
1078 break;
1079 prev = cap;
1080 vino = cap->ci->i_vino;
1081 spin_unlock(&session->s_cap_lock);
1082
1083 inode = ceph_find_inode(sb, vino);
1084 iput(inode);
1085
1086 spin_lock(&session->s_cap_lock);
1087 }
1088 }
1089 spin_unlock(&session->s_cap_lock);
1090
1091 BUG_ON(session->s_nr_caps > 0);
1092 BUG_ON(!list_empty(&session->s_cap_flushing));
1093 cleanup_cap_releases(session);
1094 }
1095
1096 /*
1097 * wake up any threads waiting on this session's caps. if the cap is
1098 * old (didn't get renewed on the client reconnect), remove it now.
1099 *
1100 * caller must hold s_mutex.
1101 */
1102 static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
1103 void *arg)
1104 {
1105 struct ceph_inode_info *ci = ceph_inode(inode);
1106
1107 wake_up_all(&ci->i_cap_wq);
1108 if (arg) {
1109 spin_lock(&ci->i_ceph_lock);
1110 ci->i_wanted_max_size = 0;
1111 ci->i_requested_max_size = 0;
1112 spin_unlock(&ci->i_ceph_lock);
1113 }
1114 return 0;
1115 }
1116
1117 static void wake_up_session_caps(struct ceph_mds_session *session,
1118 int reconnect)
1119 {
1120 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
1121 iterate_session_caps(session, wake_up_session_cb,
1122 (void *)(unsigned long)reconnect);
1123 }
1124
1125 /*
1126 * Send periodic message to MDS renewing all currently held caps. The
1127 * ack will reset the expiration for all caps from this session.
1128 *
1129 * caller holds s_mutex
1130 */
1131 static int send_renew_caps(struct ceph_mds_client *mdsc,
1132 struct ceph_mds_session *session)
1133 {
1134 struct ceph_msg *msg;
1135 int state;
1136
1137 if (time_after_eq(jiffies, session->s_cap_ttl) &&
1138 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
1139 pr_info("mds%d caps stale\n", session->s_mds);
1140 session->s_renew_requested = jiffies;
1141
1142 /* do not try to renew caps until a recovering mds has reconnected
1143 * with its clients. */
1144 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
1145 if (state < CEPH_MDS_STATE_RECONNECT) {
1146 dout("send_renew_caps ignoring mds%d (%s)\n",
1147 session->s_mds, ceph_mds_state_name(state));
1148 return 0;
1149 }
1150
1151 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
1152 ceph_mds_state_name(state));
1153 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
1154 ++session->s_renew_seq);
1155 if (!msg)
1156 return -ENOMEM;
1157 ceph_con_send(&session->s_con, msg);
1158 return 0;
1159 }
1160
1161 static int send_flushmsg_ack(struct ceph_mds_client *mdsc,
1162 struct ceph_mds_session *session, u64 seq)
1163 {
1164 struct ceph_msg *msg;
1165
1166 dout("send_flushmsg_ack to mds%d (%s)s seq %lld\n",
1167 session->s_mds, session_state_name(session->s_state), seq);
1168 msg = create_session_msg(CEPH_SESSION_FLUSHMSG_ACK, seq);
1169 if (!msg)
1170 return -ENOMEM;
1171 ceph_con_send(&session->s_con, msg);
1172 return 0;
1173 }
1174
1175
1176 /*
1177 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
1178 *
1179 * Called under session->s_mutex
1180 */
1181 static void renewed_caps(struct ceph_mds_client *mdsc,
1182 struct ceph_mds_session *session, int is_renew)
1183 {
1184 int was_stale;
1185 int wake = 0;
1186
1187 spin_lock(&session->s_cap_lock);
1188 was_stale = is_renew && time_after_eq(jiffies, session->s_cap_ttl);
1189
1190 session->s_cap_ttl = session->s_renew_requested +
1191 mdsc->mdsmap->m_session_timeout*HZ;
1192
1193 if (was_stale) {
1194 if (time_before(jiffies, session->s_cap_ttl)) {
1195 pr_info("mds%d caps renewed\n", session->s_mds);
1196 wake = 1;
1197 } else {
1198 pr_info("mds%d caps still stale\n", session->s_mds);
1199 }
1200 }
1201 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
1202 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
1203 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
1204 spin_unlock(&session->s_cap_lock);
1205
1206 if (wake)
1207 wake_up_session_caps(session, 0);
1208 }
1209
1210 /*
1211 * send a session close request
1212 */
1213 static int request_close_session(struct ceph_mds_client *mdsc,
1214 struct ceph_mds_session *session)
1215 {
1216 struct ceph_msg *msg;
1217
1218 dout("request_close_session mds%d state %s seq %lld\n",
1219 session->s_mds, session_state_name(session->s_state),
1220 session->s_seq);
1221 msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
1222 if (!msg)
1223 return -ENOMEM;
1224 ceph_con_send(&session->s_con, msg);
1225 return 0;
1226 }
1227
1228 /*
1229 * Called with s_mutex held.
1230 */
1231 static int __close_session(struct ceph_mds_client *mdsc,
1232 struct ceph_mds_session *session)
1233 {
1234 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
1235 return 0;
1236 session->s_state = CEPH_MDS_SESSION_CLOSING;
1237 return request_close_session(mdsc, session);
1238 }
1239
1240 /*
1241 * Trim old(er) caps.
1242 *
1243 * Because we can't cache an inode without one or more caps, we do
1244 * this indirectly: if a cap is unused, we prune its aliases, at which
1245 * point the inode will hopefully get dropped to.
1246 *
1247 * Yes, this is a bit sloppy. Our only real goal here is to respond to
1248 * memory pressure from the MDS, though, so it needn't be perfect.
1249 */
1250 static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
1251 {
1252 struct ceph_mds_session *session = arg;
1253 struct ceph_inode_info *ci = ceph_inode(inode);
1254 int used, wanted, oissued, mine;
1255
1256 if (session->s_trim_caps <= 0)
1257 return -1;
1258
1259 spin_lock(&ci->i_ceph_lock);
1260 mine = cap->issued | cap->implemented;
1261 used = __ceph_caps_used(ci);
1262 wanted = __ceph_caps_file_wanted(ci);
1263 oissued = __ceph_caps_issued_other(ci, cap);
1264
1265 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s wanted %s\n",
1266 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
1267 ceph_cap_string(used), ceph_cap_string(wanted));
1268 if (cap == ci->i_auth_cap) {
1269 if (ci->i_dirty_caps | ci->i_flushing_caps)
1270 goto out;
1271 if ((used | wanted) & CEPH_CAP_ANY_WR)
1272 goto out;
1273 }
1274 if ((used | wanted) & ~oissued & mine)
1275 goto out; /* we need these caps */
1276
1277 session->s_trim_caps--;
1278 if (oissued) {
1279 /* we aren't the only cap.. just remove us */
1280 __ceph_remove_cap(cap, true);
1281 } else {
1282 /* try to drop referring dentries */
1283 spin_unlock(&ci->i_ceph_lock);
1284 d_prune_aliases(inode);
1285 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
1286 inode, cap, atomic_read(&inode->i_count));
1287 return 0;
1288 }
1289
1290 out:
1291 spin_unlock(&ci->i_ceph_lock);
1292 return 0;
1293 }
1294
1295 /*
1296 * Trim session cap count down to some max number.
1297 */
1298 static int trim_caps(struct ceph_mds_client *mdsc,
1299 struct ceph_mds_session *session,
1300 int max_caps)
1301 {
1302 int trim_caps = session->s_nr_caps - max_caps;
1303
1304 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1305 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1306 if (trim_caps > 0) {
1307 session->s_trim_caps = trim_caps;
1308 iterate_session_caps(session, trim_caps_cb, session);
1309 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1310 session->s_mds, session->s_nr_caps, max_caps,
1311 trim_caps - session->s_trim_caps);
1312 session->s_trim_caps = 0;
1313 }
1314
1315 ceph_add_cap_releases(mdsc, session);
1316 ceph_send_cap_releases(mdsc, session);
1317 return 0;
1318 }
1319
1320 /*
1321 * Allocate cap_release messages. If there is a partially full message
1322 * in the queue, try to allocate enough to cover it's remainder, so that
1323 * we can send it immediately.
1324 *
1325 * Called under s_mutex.
1326 */
1327 int ceph_add_cap_releases(struct ceph_mds_client *mdsc,
1328 struct ceph_mds_session *session)
1329 {
1330 struct ceph_msg *msg, *partial = NULL;
1331 struct ceph_mds_cap_release *head;
1332 int err = -ENOMEM;
1333 int extra = mdsc->fsc->mount_options->cap_release_safety;
1334 int num;
1335
1336 dout("add_cap_releases %p mds%d extra %d\n", session, session->s_mds,
1337 extra);
1338
1339 spin_lock(&session->s_cap_lock);
1340
1341 if (!list_empty(&session->s_cap_releases)) {
1342 msg = list_first_entry(&session->s_cap_releases,
1343 struct ceph_msg,
1344 list_head);
1345 head = msg->front.iov_base;
1346 num = le32_to_cpu(head->num);
1347 if (num) {
1348 dout(" partial %p with (%d/%d)\n", msg, num,
1349 (int)CEPH_CAPS_PER_RELEASE);
1350 extra += CEPH_CAPS_PER_RELEASE - num;
1351 partial = msg;
1352 }
1353 }
1354 while (session->s_num_cap_releases < session->s_nr_caps + extra) {
1355 spin_unlock(&session->s_cap_lock);
1356 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
1357 GFP_NOFS, false);
1358 if (!msg)
1359 goto out_unlocked;
1360 dout("add_cap_releases %p msg %p now %d\n", session, msg,
1361 (int)msg->front.iov_len);
1362 head = msg->front.iov_base;
1363 head->num = cpu_to_le32(0);
1364 msg->front.iov_len = sizeof(*head);
1365 spin_lock(&session->s_cap_lock);
1366 list_add(&msg->list_head, &session->s_cap_releases);
1367 session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
1368 }
1369
1370 if (partial) {
1371 head = partial->front.iov_base;
1372 num = le32_to_cpu(head->num);
1373 dout(" queueing partial %p with %d/%d\n", partial, num,
1374 (int)CEPH_CAPS_PER_RELEASE);
1375 list_move_tail(&partial->list_head,
1376 &session->s_cap_releases_done);
1377 session->s_num_cap_releases -= CEPH_CAPS_PER_RELEASE - num;
1378 }
1379 err = 0;
1380 spin_unlock(&session->s_cap_lock);
1381 out_unlocked:
1382 return err;
1383 }
1384
1385 /*
1386 * flush all dirty inode data to disk.
1387 *
1388 * returns true if we've flushed through want_flush_seq
1389 */
1390 static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
1391 {
1392 int mds, ret = 1;
1393
1394 dout("check_cap_flush want %lld\n", want_flush_seq);
1395 mutex_lock(&mdsc->mutex);
1396 for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
1397 struct ceph_mds_session *session = mdsc->sessions[mds];
1398
1399 if (!session)
1400 continue;
1401 get_session(session);
1402 mutex_unlock(&mdsc->mutex);
1403
1404 mutex_lock(&session->s_mutex);
1405 if (!list_empty(&session->s_cap_flushing)) {
1406 struct ceph_inode_info *ci =
1407 list_entry(session->s_cap_flushing.next,
1408 struct ceph_inode_info,
1409 i_flushing_item);
1410 struct inode *inode = &ci->vfs_inode;
1411
1412 spin_lock(&ci->i_ceph_lock);
1413 if (ci->i_cap_flush_seq <= want_flush_seq) {
1414 dout("check_cap_flush still flushing %p "
1415 "seq %lld <= %lld to mds%d\n", inode,
1416 ci->i_cap_flush_seq, want_flush_seq,
1417 session->s_mds);
1418 ret = 0;
1419 }
1420 spin_unlock(&ci->i_ceph_lock);
1421 }
1422 mutex_unlock(&session->s_mutex);
1423 ceph_put_mds_session(session);
1424
1425 if (!ret)
1426 return ret;
1427 mutex_lock(&mdsc->mutex);
1428 }
1429
1430 mutex_unlock(&mdsc->mutex);
1431 dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
1432 return ret;
1433 }
1434
1435 /*
1436 * called under s_mutex
1437 */
1438 void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
1439 struct ceph_mds_session *session)
1440 {
1441 struct ceph_msg *msg;
1442
1443 dout("send_cap_releases mds%d\n", session->s_mds);
1444 spin_lock(&session->s_cap_lock);
1445 while (!list_empty(&session->s_cap_releases_done)) {
1446 msg = list_first_entry(&session->s_cap_releases_done,
1447 struct ceph_msg, list_head);
1448 list_del_init(&msg->list_head);
1449 spin_unlock(&session->s_cap_lock);
1450 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1451 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1452 ceph_con_send(&session->s_con, msg);
1453 spin_lock(&session->s_cap_lock);
1454 }
1455 spin_unlock(&session->s_cap_lock);
1456 }
1457
1458 static void discard_cap_releases(struct ceph_mds_client *mdsc,
1459 struct ceph_mds_session *session)
1460 {
1461 struct ceph_msg *msg;
1462 struct ceph_mds_cap_release *head;
1463 unsigned num;
1464
1465 dout("discard_cap_releases mds%d\n", session->s_mds);
1466
1467 if (!list_empty(&session->s_cap_releases)) {
1468 /* zero out the in-progress message */
1469 msg = list_first_entry(&session->s_cap_releases,
1470 struct ceph_msg, list_head);
1471 head = msg->front.iov_base;
1472 num = le32_to_cpu(head->num);
1473 dout("discard_cap_releases mds%d %p %u\n",
1474 session->s_mds, msg, num);
1475 head->num = cpu_to_le32(0);
1476 msg->front.iov_len = sizeof(*head);
1477 session->s_num_cap_releases += num;
1478 }
1479
1480 /* requeue completed messages */
1481 while (!list_empty(&session->s_cap_releases_done)) {
1482 msg = list_first_entry(&session->s_cap_releases_done,
1483 struct ceph_msg, list_head);
1484 list_del_init(&msg->list_head);
1485
1486 head = msg->front.iov_base;
1487 num = le32_to_cpu(head->num);
1488 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg,
1489 num);
1490 session->s_num_cap_releases += num;
1491 head->num = cpu_to_le32(0);
1492 msg->front.iov_len = sizeof(*head);
1493 list_add(&msg->list_head, &session->s_cap_releases);
1494 }
1495 }
1496
1497 /*
1498 * requests
1499 */
1500
1501 int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
1502 struct inode *dir)
1503 {
1504 struct ceph_inode_info *ci = ceph_inode(dir);
1505 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1506 struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options;
1507 size_t size = sizeof(*rinfo->dir_in) + sizeof(*rinfo->dir_dname_len) +
1508 sizeof(*rinfo->dir_dname) + sizeof(*rinfo->dir_dlease);
1509 int order, num_entries;
1510
1511 spin_lock(&ci->i_ceph_lock);
1512 num_entries = ci->i_files + ci->i_subdirs;
1513 spin_unlock(&ci->i_ceph_lock);
1514 num_entries = max(num_entries, 1);
1515 num_entries = min(num_entries, opt->max_readdir);
1516
1517 order = get_order(size * num_entries);
1518 while (order >= 0) {
1519 rinfo->dir_in = (void*)__get_free_pages(GFP_NOFS | __GFP_NOWARN,
1520 order);
1521 if (rinfo->dir_in)
1522 break;
1523 order--;
1524 }
1525 if (!rinfo->dir_in)
1526 return -ENOMEM;
1527
1528 num_entries = (PAGE_SIZE << order) / size;
1529 num_entries = min(num_entries, opt->max_readdir);
1530
1531 rinfo->dir_buf_size = PAGE_SIZE << order;
1532 req->r_num_caps = num_entries + 1;
1533 req->r_args.readdir.max_entries = cpu_to_le32(num_entries);
1534 req->r_args.readdir.max_bytes = cpu_to_le32(opt->max_readdir_bytes);
1535 return 0;
1536 }
1537
1538 /*
1539 * Create an mds request.
1540 */
1541 struct ceph_mds_request *
1542 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1543 {
1544 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1545
1546 if (!req)
1547 return ERR_PTR(-ENOMEM);
1548
1549 mutex_init(&req->r_fill_mutex);
1550 req->r_mdsc = mdsc;
1551 req->r_started = jiffies;
1552 req->r_resend_mds = -1;
1553 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1554 req->r_fmode = -1;
1555 kref_init(&req->r_kref);
1556 INIT_LIST_HEAD(&req->r_wait);
1557 init_completion(&req->r_completion);
1558 init_completion(&req->r_safe_completion);
1559 INIT_LIST_HEAD(&req->r_unsafe_item);
1560
1561 req->r_stamp = CURRENT_TIME;
1562
1563 req->r_op = op;
1564 req->r_direct_mode = mode;
1565 return req;
1566 }
1567
1568 /*
1569 * return oldest (lowest) request, tid in request tree, 0 if none.
1570 *
1571 * called under mdsc->mutex.
1572 */
1573 static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1574 {
1575 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1576 return NULL;
1577 return rb_entry(rb_first(&mdsc->request_tree),
1578 struct ceph_mds_request, r_node);
1579 }
1580
1581 static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1582 {
1583 struct ceph_mds_request *req = __get_oldest_req(mdsc);
1584
1585 if (req)
1586 return req->r_tid;
1587 return 0;
1588 }
1589
1590 /*
1591 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1592 * on build_path_from_dentry in fs/cifs/dir.c.
1593 *
1594 * If @stop_on_nosnap, generate path relative to the first non-snapped
1595 * inode.
1596 *
1597 * Encode hidden .snap dirs as a double /, i.e.
1598 * foo/.snap/bar -> foo//bar
1599 */
1600 char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1601 int stop_on_nosnap)
1602 {
1603 struct dentry *temp;
1604 char *path;
1605 int len, pos;
1606 unsigned seq;
1607
1608 if (dentry == NULL)
1609 return ERR_PTR(-EINVAL);
1610
1611 retry:
1612 len = 0;
1613 seq = read_seqbegin(&rename_lock);
1614 rcu_read_lock();
1615 for (temp = dentry; !IS_ROOT(temp);) {
1616 struct inode *inode = temp->d_inode;
1617 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1618 len++; /* slash only */
1619 else if (stop_on_nosnap && inode &&
1620 ceph_snap(inode) == CEPH_NOSNAP)
1621 break;
1622 else
1623 len += 1 + temp->d_name.len;
1624 temp = temp->d_parent;
1625 }
1626 rcu_read_unlock();
1627 if (len)
1628 len--; /* no leading '/' */
1629
1630 path = kmalloc(len+1, GFP_NOFS);
1631 if (path == NULL)
1632 return ERR_PTR(-ENOMEM);
1633 pos = len;
1634 path[pos] = 0; /* trailing null */
1635 rcu_read_lock();
1636 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1637 struct inode *inode;
1638
1639 spin_lock(&temp->d_lock);
1640 inode = temp->d_inode;
1641 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1642 dout("build_path path+%d: %p SNAPDIR\n",
1643 pos, temp);
1644 } else if (stop_on_nosnap && inode &&
1645 ceph_snap(inode) == CEPH_NOSNAP) {
1646 spin_unlock(&temp->d_lock);
1647 break;
1648 } else {
1649 pos -= temp->d_name.len;
1650 if (pos < 0) {
1651 spin_unlock(&temp->d_lock);
1652 break;
1653 }
1654 strncpy(path + pos, temp->d_name.name,
1655 temp->d_name.len);
1656 }
1657 spin_unlock(&temp->d_lock);
1658 if (pos)
1659 path[--pos] = '/';
1660 temp = temp->d_parent;
1661 }
1662 rcu_read_unlock();
1663 if (pos != 0 || read_seqretry(&rename_lock, seq)) {
1664 pr_err("build_path did not end path lookup where "
1665 "expected, namelen is %d, pos is %d\n", len, pos);
1666 /* presumably this is only possible if racing with a
1667 rename of one of the parent directories (we can not
1668 lock the dentries above us to prevent this, but
1669 retrying should be harmless) */
1670 kfree(path);
1671 goto retry;
1672 }
1673
1674 *base = ceph_ino(temp->d_inode);
1675 *plen = len;
1676 dout("build_path on %p %d built %llx '%.*s'\n",
1677 dentry, d_count(dentry), *base, len, path);
1678 return path;
1679 }
1680
1681 static int build_dentry_path(struct dentry *dentry,
1682 const char **ppath, int *ppathlen, u64 *pino,
1683 int *pfreepath)
1684 {
1685 char *path;
1686
1687 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1688 *pino = ceph_ino(dentry->d_parent->d_inode);
1689 *ppath = dentry->d_name.name;
1690 *ppathlen = dentry->d_name.len;
1691 return 0;
1692 }
1693 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1694 if (IS_ERR(path))
1695 return PTR_ERR(path);
1696 *ppath = path;
1697 *pfreepath = 1;
1698 return 0;
1699 }
1700
1701 static int build_inode_path(struct inode *inode,
1702 const char **ppath, int *ppathlen, u64 *pino,
1703 int *pfreepath)
1704 {
1705 struct dentry *dentry;
1706 char *path;
1707
1708 if (ceph_snap(inode) == CEPH_NOSNAP) {
1709 *pino = ceph_ino(inode);
1710 *ppathlen = 0;
1711 return 0;
1712 }
1713 dentry = d_find_alias(inode);
1714 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1715 dput(dentry);
1716 if (IS_ERR(path))
1717 return PTR_ERR(path);
1718 *ppath = path;
1719 *pfreepath = 1;
1720 return 0;
1721 }
1722
1723 /*
1724 * request arguments may be specified via an inode *, a dentry *, or
1725 * an explicit ino+path.
1726 */
1727 static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1728 const char *rpath, u64 rino,
1729 const char **ppath, int *pathlen,
1730 u64 *ino, int *freepath)
1731 {
1732 int r = 0;
1733
1734 if (rinode) {
1735 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1736 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1737 ceph_snap(rinode));
1738 } else if (rdentry) {
1739 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1740 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1741 *ppath);
1742 } else if (rpath || rino) {
1743 *ino = rino;
1744 *ppath = rpath;
1745 *pathlen = rpath ? strlen(rpath) : 0;
1746 dout(" path %.*s\n", *pathlen, rpath);
1747 }
1748
1749 return r;
1750 }
1751
1752 /*
1753 * called under mdsc->mutex
1754 */
1755 static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1756 struct ceph_mds_request *req,
1757 int mds)
1758 {
1759 struct ceph_msg *msg;
1760 struct ceph_mds_request_head *head;
1761 const char *path1 = NULL;
1762 const char *path2 = NULL;
1763 u64 ino1 = 0, ino2 = 0;
1764 int pathlen1 = 0, pathlen2 = 0;
1765 int freepath1 = 0, freepath2 = 0;
1766 int len;
1767 u16 releases;
1768 void *p, *end;
1769 int ret;
1770
1771 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1772 req->r_path1, req->r_ino1.ino,
1773 &path1, &pathlen1, &ino1, &freepath1);
1774 if (ret < 0) {
1775 msg = ERR_PTR(ret);
1776 goto out;
1777 }
1778
1779 ret = set_request_path_attr(NULL, req->r_old_dentry,
1780 req->r_path2, req->r_ino2.ino,
1781 &path2, &pathlen2, &ino2, &freepath2);
1782 if (ret < 0) {
1783 msg = ERR_PTR(ret);
1784 goto out_free1;
1785 }
1786
1787 len = sizeof(*head) +
1788 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64)) +
1789 sizeof(struct timespec);
1790
1791 /* calculate (max) length for cap releases */
1792 len += sizeof(struct ceph_mds_request_release) *
1793 (!!req->r_inode_drop + !!req->r_dentry_drop +
1794 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1795 if (req->r_dentry_drop)
1796 len += req->r_dentry->d_name.len;
1797 if (req->r_old_dentry_drop)
1798 len += req->r_old_dentry->d_name.len;
1799
1800 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS, false);
1801 if (!msg) {
1802 msg = ERR_PTR(-ENOMEM);
1803 goto out_free2;
1804 }
1805
1806 msg->hdr.version = 2;
1807 msg->hdr.tid = cpu_to_le64(req->r_tid);
1808
1809 head = msg->front.iov_base;
1810 p = msg->front.iov_base + sizeof(*head);
1811 end = msg->front.iov_base + msg->front.iov_len;
1812
1813 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1814 head->op = cpu_to_le32(req->r_op);
1815 head->caller_uid = cpu_to_le32(from_kuid(&init_user_ns, req->r_uid));
1816 head->caller_gid = cpu_to_le32(from_kgid(&init_user_ns, req->r_gid));
1817 head->args = req->r_args;
1818
1819 ceph_encode_filepath(&p, end, ino1, path1);
1820 ceph_encode_filepath(&p, end, ino2, path2);
1821
1822 /* make note of release offset, in case we need to replay */
1823 req->r_request_release_offset = p - msg->front.iov_base;
1824
1825 /* cap releases */
1826 releases = 0;
1827 if (req->r_inode_drop)
1828 releases += ceph_encode_inode_release(&p,
1829 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1830 mds, req->r_inode_drop, req->r_inode_unless, 0);
1831 if (req->r_dentry_drop)
1832 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1833 mds, req->r_dentry_drop, req->r_dentry_unless);
1834 if (req->r_old_dentry_drop)
1835 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1836 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1837 if (req->r_old_inode_drop)
1838 releases += ceph_encode_inode_release(&p,
1839 req->r_old_dentry->d_inode,
1840 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1841 head->num_releases = cpu_to_le16(releases);
1842
1843 /* time stamp */
1844 ceph_encode_copy(&p, &req->r_stamp, sizeof(req->r_stamp));
1845
1846 BUG_ON(p > end);
1847 msg->front.iov_len = p - msg->front.iov_base;
1848 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1849
1850 if (req->r_data_len) {
1851 /* outbound data set only by ceph_sync_setxattr() */
1852 BUG_ON(!req->r_pages);
1853 ceph_msg_data_add_pages(msg, req->r_pages, req->r_data_len, 0);
1854 }
1855
1856 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1857 msg->hdr.data_off = cpu_to_le16(0);
1858
1859 out_free2:
1860 if (freepath2)
1861 kfree((char *)path2);
1862 out_free1:
1863 if (freepath1)
1864 kfree((char *)path1);
1865 out:
1866 return msg;
1867 }
1868
1869 /*
1870 * called under mdsc->mutex if error, under no mutex if
1871 * success.
1872 */
1873 static void complete_request(struct ceph_mds_client *mdsc,
1874 struct ceph_mds_request *req)
1875 {
1876 if (req->r_callback)
1877 req->r_callback(mdsc, req);
1878 else
1879 complete_all(&req->r_completion);
1880 }
1881
1882 /*
1883 * called under mdsc->mutex
1884 */
1885 static int __prepare_send_request(struct ceph_mds_client *mdsc,
1886 struct ceph_mds_request *req,
1887 int mds)
1888 {
1889 struct ceph_mds_request_head *rhead;
1890 struct ceph_msg *msg;
1891 int flags = 0;
1892
1893 req->r_attempts++;
1894 if (req->r_inode) {
1895 struct ceph_cap *cap =
1896 ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
1897
1898 if (cap)
1899 req->r_sent_on_mseq = cap->mseq;
1900 else
1901 req->r_sent_on_mseq = -1;
1902 }
1903 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1904 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1905
1906 if (req->r_got_unsafe) {
1907 /*
1908 * Replay. Do not regenerate message (and rebuild
1909 * paths, etc.); just use the original message.
1910 * Rebuilding paths will break for renames because
1911 * d_move mangles the src name.
1912 */
1913 msg = req->r_request;
1914 rhead = msg->front.iov_base;
1915
1916 flags = le32_to_cpu(rhead->flags);
1917 flags |= CEPH_MDS_FLAG_REPLAY;
1918 rhead->flags = cpu_to_le32(flags);
1919
1920 if (req->r_target_inode)
1921 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1922
1923 rhead->num_retry = req->r_attempts - 1;
1924
1925 /* remove cap/dentry releases from message */
1926 rhead->num_releases = 0;
1927 msg->hdr.front_len = cpu_to_le32(req->r_request_release_offset);
1928 msg->front.iov_len = req->r_request_release_offset;
1929 return 0;
1930 }
1931
1932 if (req->r_request) {
1933 ceph_msg_put(req->r_request);
1934 req->r_request = NULL;
1935 }
1936 msg = create_request_message(mdsc, req, mds);
1937 if (IS_ERR(msg)) {
1938 req->r_err = PTR_ERR(msg);
1939 complete_request(mdsc, req);
1940 return PTR_ERR(msg);
1941 }
1942 req->r_request = msg;
1943
1944 rhead = msg->front.iov_base;
1945 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1946 if (req->r_got_unsafe)
1947 flags |= CEPH_MDS_FLAG_REPLAY;
1948 if (req->r_locked_dir)
1949 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1950 rhead->flags = cpu_to_le32(flags);
1951 rhead->num_fwd = req->r_num_fwd;
1952 rhead->num_retry = req->r_attempts - 1;
1953 rhead->ino = 0;
1954
1955 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1956 return 0;
1957 }
1958
1959 /*
1960 * send request, or put it on the appropriate wait list.
1961 */
1962 static int __do_request(struct ceph_mds_client *mdsc,
1963 struct ceph_mds_request *req)
1964 {
1965 struct ceph_mds_session *session = NULL;
1966 int mds = -1;
1967 int err = -EAGAIN;
1968
1969 if (req->r_err || req->r_got_result) {
1970 if (req->r_aborted)
1971 __unregister_request(mdsc, req);
1972 goto out;
1973 }
1974
1975 if (req->r_timeout &&
1976 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1977 dout("do_request timed out\n");
1978 err = -EIO;
1979 goto finish;
1980 }
1981
1982 put_request_session(req);
1983
1984 mds = __choose_mds(mdsc, req);
1985 if (mds < 0 ||
1986 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1987 dout("do_request no mds or not active, waiting for map\n");
1988 list_add(&req->r_wait, &mdsc->waiting_for_map);
1989 goto out;
1990 }
1991
1992 /* get, open session */
1993 session = __ceph_lookup_mds_session(mdsc, mds);
1994 if (!session) {
1995 session = register_session(mdsc, mds);
1996 if (IS_ERR(session)) {
1997 err = PTR_ERR(session);
1998 goto finish;
1999 }
2000 }
2001 req->r_session = get_session(session);
2002
2003 dout("do_request mds%d session %p state %s\n", mds, session,
2004 session_state_name(session->s_state));
2005 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
2006 session->s_state != CEPH_MDS_SESSION_HUNG) {
2007 if (session->s_state == CEPH_MDS_SESSION_NEW ||
2008 session->s_state == CEPH_MDS_SESSION_CLOSING)
2009 __open_session(mdsc, session);
2010 list_add(&req->r_wait, &session->s_waiting);
2011 goto out_session;
2012 }
2013
2014 /* send request */
2015 req->r_resend_mds = -1; /* forget any previous mds hint */
2016
2017 if (req->r_request_started == 0) /* note request start time */
2018 req->r_request_started = jiffies;
2019
2020 err = __prepare_send_request(mdsc, req, mds);
2021 if (!err) {
2022 ceph_msg_get(req->r_request);
2023 ceph_con_send(&session->s_con, req->r_request);
2024 }
2025
2026 out_session:
2027 ceph_put_mds_session(session);
2028 out:
2029 return err;
2030
2031 finish:
2032 req->r_err = err;
2033 complete_request(mdsc, req);
2034 goto out;
2035 }
2036
2037 /*
2038 * called under mdsc->mutex
2039 */
2040 static void __wake_requests(struct ceph_mds_client *mdsc,
2041 struct list_head *head)
2042 {
2043 struct ceph_mds_request *req;
2044 LIST_HEAD(tmp_list);
2045
2046 list_splice_init(head, &tmp_list);
2047
2048 while (!list_empty(&tmp_list)) {
2049 req = list_entry(tmp_list.next,
2050 struct ceph_mds_request, r_wait);
2051 list_del_init(&req->r_wait);
2052 dout(" wake request %p tid %llu\n", req, req->r_tid);
2053 __do_request(mdsc, req);
2054 }
2055 }
2056
2057 /*
2058 * Wake up threads with requests pending for @mds, so that they can
2059 * resubmit their requests to a possibly different mds.
2060 */
2061 static void kick_requests(struct ceph_mds_client *mdsc, int mds)
2062 {
2063 struct ceph_mds_request *req;
2064 struct rb_node *p;
2065
2066 dout("kick_requests mds%d\n", mds);
2067 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
2068 req = rb_entry(p, struct ceph_mds_request, r_node);
2069 if (req->r_got_unsafe)
2070 continue;
2071 if (req->r_session &&
2072 req->r_session->s_mds == mds) {
2073 dout(" kicking tid %llu\n", req->r_tid);
2074 __do_request(mdsc, req);
2075 }
2076 }
2077 }
2078
2079 void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
2080 struct ceph_mds_request *req)
2081 {
2082 dout("submit_request on %p\n", req);
2083 mutex_lock(&mdsc->mutex);
2084 __register_request(mdsc, req, NULL);
2085 __do_request(mdsc, req);
2086 mutex_unlock(&mdsc->mutex);
2087 }
2088
2089 /*
2090 * Synchrously perform an mds request. Take care of all of the
2091 * session setup, forwarding, retry details.
2092 */
2093 int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
2094 struct inode *dir,
2095 struct ceph_mds_request *req)
2096 {
2097 int err;
2098
2099 dout("do_request on %p\n", req);
2100
2101 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
2102 if (req->r_inode)
2103 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
2104 if (req->r_locked_dir)
2105 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
2106 if (req->r_old_dentry_dir)
2107 ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
2108 CEPH_CAP_PIN);
2109
2110 /* issue */
2111 mutex_lock(&mdsc->mutex);
2112 __register_request(mdsc, req, dir);
2113 __do_request(mdsc, req);
2114
2115 if (req->r_err) {
2116 err = req->r_err;
2117 __unregister_request(mdsc, req);
2118 dout("do_request early error %d\n", err);
2119 goto out;
2120 }
2121
2122 /* wait */
2123 mutex_unlock(&mdsc->mutex);
2124 dout("do_request waiting\n");
2125 if (req->r_timeout) {
2126 err = (long)wait_for_completion_killable_timeout(
2127 &req->r_completion, req->r_timeout);
2128 if (err == 0)
2129 err = -EIO;
2130 } else {
2131 err = wait_for_completion_killable(&req->r_completion);
2132 }
2133 dout("do_request waited, got %d\n", err);
2134 mutex_lock(&mdsc->mutex);
2135
2136 /* only abort if we didn't race with a real reply */
2137 if (req->r_got_result) {
2138 err = le32_to_cpu(req->r_reply_info.head->result);
2139 } else if (err < 0) {
2140 dout("aborted request %lld with %d\n", req->r_tid, err);
2141
2142 /*
2143 * ensure we aren't running concurrently with
2144 * ceph_fill_trace or ceph_readdir_prepopulate, which
2145 * rely on locks (dir mutex) held by our caller.
2146 */
2147 mutex_lock(&req->r_fill_mutex);
2148 req->r_err = err;
2149 req->r_aborted = true;
2150 mutex_unlock(&req->r_fill_mutex);
2151
2152 if (req->r_locked_dir &&
2153 (req->r_op & CEPH_MDS_OP_WRITE))
2154 ceph_invalidate_dir_request(req);
2155 } else {
2156 err = req->r_err;
2157 }
2158
2159 out:
2160 mutex_unlock(&mdsc->mutex);
2161 dout("do_request %p done, result %d\n", req, err);
2162 return err;
2163 }
2164
2165 /*
2166 * Invalidate dir's completeness, dentry lease state on an aborted MDS
2167 * namespace request.
2168 */
2169 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
2170 {
2171 struct inode *inode = req->r_locked_dir;
2172
2173 dout("invalidate_dir_request %p (complete, lease(s))\n", inode);
2174
2175 ceph_dir_clear_complete(inode);
2176 if (req->r_dentry)
2177 ceph_invalidate_dentry_lease(req->r_dentry);
2178 if (req->r_old_dentry)
2179 ceph_invalidate_dentry_lease(req->r_old_dentry);
2180 }
2181
2182 /*
2183 * Handle mds reply.
2184 *
2185 * We take the session mutex and parse and process the reply immediately.
2186 * This preserves the logical ordering of replies, capabilities, etc., sent
2187 * by the MDS as they are applied to our local cache.
2188 */
2189 static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
2190 {
2191 struct ceph_mds_client *mdsc = session->s_mdsc;
2192 struct ceph_mds_request *req;
2193 struct ceph_mds_reply_head *head = msg->front.iov_base;
2194 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
2195 u64 tid;
2196 int err, result;
2197 int mds = session->s_mds;
2198
2199 if (msg->front.iov_len < sizeof(*head)) {
2200 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
2201 ceph_msg_dump(msg);
2202 return;
2203 }
2204
2205 /* get request, session */
2206 tid = le64_to_cpu(msg->hdr.tid);
2207 mutex_lock(&mdsc->mutex);
2208 req = __lookup_request(mdsc, tid);
2209 if (!req) {
2210 dout("handle_reply on unknown tid %llu\n", tid);
2211 mutex_unlock(&mdsc->mutex);
2212 return;
2213 }
2214 dout("handle_reply %p\n", req);
2215
2216 /* correct session? */
2217 if (req->r_session != session) {
2218 pr_err("mdsc_handle_reply got %llu on session mds%d"
2219 " not mds%d\n", tid, session->s_mds,
2220 req->r_session ? req->r_session->s_mds : -1);
2221 mutex_unlock(&mdsc->mutex);
2222 goto out;
2223 }
2224
2225 /* dup? */
2226 if ((req->r_got_unsafe && !head->safe) ||
2227 (req->r_got_safe && head->safe)) {
2228 pr_warn("got a dup %s reply on %llu from mds%d\n",
2229 head->safe ? "safe" : "unsafe", tid, mds);
2230 mutex_unlock(&mdsc->mutex);
2231 goto out;
2232 }
2233 if (req->r_got_safe && !head->safe) {
2234 pr_warn("got unsafe after safe on %llu from mds%d\n",
2235 tid, mds);
2236 mutex_unlock(&mdsc->mutex);
2237 goto out;
2238 }
2239
2240 result = le32_to_cpu(head->result);
2241
2242 /*
2243 * Handle an ESTALE
2244 * if we're not talking to the authority, send to them
2245 * if the authority has changed while we weren't looking,
2246 * send to new authority
2247 * Otherwise we just have to return an ESTALE
2248 */
2249 if (result == -ESTALE) {
2250 dout("got ESTALE on request %llu", req->r_tid);
2251 if (req->r_direct_mode != USE_AUTH_MDS) {
2252 dout("not using auth, setting for that now");
2253 req->r_direct_mode = USE_AUTH_MDS;
2254 __do_request(mdsc, req);
2255 mutex_unlock(&mdsc->mutex);
2256 goto out;
2257 } else {
2258 int mds = __choose_mds(mdsc, req);
2259 if (mds >= 0 && mds != req->r_session->s_mds) {
2260 dout("but auth changed, so resending");
2261 __do_request(mdsc, req);
2262 mutex_unlock(&mdsc->mutex);
2263 goto out;
2264 }
2265 }
2266 dout("have to return ESTALE on request %llu", req->r_tid);
2267 }
2268
2269
2270 if (head->safe) {
2271 req->r_got_safe = true;
2272 __unregister_request(mdsc, req);
2273
2274 if (req->r_got_unsafe) {
2275 /*
2276 * We already handled the unsafe response, now do the
2277 * cleanup. No need to examine the response; the MDS
2278 * doesn't include any result info in the safe
2279 * response. And even if it did, there is nothing
2280 * useful we could do with a revised return value.
2281 */
2282 dout("got safe reply %llu, mds%d\n", tid, mds);
2283 list_del_init(&req->r_unsafe_item);
2284
2285 /* last unsafe request during umount? */
2286 if (mdsc->stopping && !__get_oldest_req(mdsc))
2287 complete_all(&mdsc->safe_umount_waiters);
2288 mutex_unlock(&mdsc->mutex);
2289 goto out;
2290 }
2291 } else {
2292 req->r_got_unsafe = true;
2293 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
2294 }
2295
2296 dout("handle_reply tid %lld result %d\n", tid, result);
2297 rinfo = &req->r_reply_info;
2298 err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
2299 mutex_unlock(&mdsc->mutex);
2300
2301 mutex_lock(&session->s_mutex);
2302 if (err < 0) {
2303 pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
2304 ceph_msg_dump(msg);
2305 goto out_err;
2306 }
2307
2308 /* snap trace */
2309 if (rinfo->snapblob_len) {
2310 down_write(&mdsc->snap_rwsem);
2311 ceph_update_snap_trace(mdsc, rinfo->snapblob,
2312 rinfo->snapblob + rinfo->snapblob_len,
2313 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
2314 downgrade_write(&mdsc->snap_rwsem);
2315 } else {
2316 down_read(&mdsc->snap_rwsem);
2317 }
2318
2319 /* insert trace into our cache */
2320 mutex_lock(&req->r_fill_mutex);
2321 err = ceph_fill_trace(mdsc->fsc->sb, req, req->r_session);
2322 if (err == 0) {
2323 if (result == 0 && (req->r_op == CEPH_MDS_OP_READDIR ||
2324 req->r_op == CEPH_MDS_OP_LSSNAP))
2325 ceph_readdir_prepopulate(req, req->r_session);
2326 ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
2327 }
2328 mutex_unlock(&req->r_fill_mutex);
2329
2330 up_read(&mdsc->snap_rwsem);
2331 out_err:
2332 mutex_lock(&mdsc->mutex);
2333 if (!req->r_aborted) {
2334 if (err) {
2335 req->r_err = err;
2336 } else {
2337 req->r_reply = msg;
2338 ceph_msg_get(msg);
2339 req->r_got_result = true;
2340 }
2341 } else {
2342 dout("reply arrived after request %lld was aborted\n", tid);
2343 }
2344 mutex_unlock(&mdsc->mutex);
2345
2346 ceph_add_cap_releases(mdsc, req->r_session);
2347 mutex_unlock(&session->s_mutex);
2348
2349 /* kick calling process */
2350 complete_request(mdsc, req);
2351 out:
2352 ceph_mdsc_put_request(req);
2353 return;
2354 }
2355
2356
2357
2358 /*
2359 * handle mds notification that our request has been forwarded.
2360 */
2361 static void handle_forward(struct ceph_mds_client *mdsc,
2362 struct ceph_mds_session *session,
2363 struct ceph_msg *msg)
2364 {
2365 struct ceph_mds_request *req;
2366 u64 tid = le64_to_cpu(msg->hdr.tid);
2367 u32 next_mds;
2368 u32 fwd_seq;
2369 int err = -EINVAL;
2370 void *p = msg->front.iov_base;
2371 void *end = p + msg->front.iov_len;
2372
2373 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
2374 next_mds = ceph_decode_32(&p);
2375 fwd_seq = ceph_decode_32(&p);
2376
2377 mutex_lock(&mdsc->mutex);
2378 req = __lookup_request(mdsc, tid);
2379 if (!req) {
2380 dout("forward tid %llu to mds%d - req dne\n", tid, next_mds);
2381 goto out; /* dup reply? */
2382 }
2383
2384 if (req->r_aborted) {
2385 dout("forward tid %llu aborted, unregistering\n", tid);
2386 __unregister_request(mdsc, req);
2387 } else if (fwd_seq <= req->r_num_fwd) {
2388 dout("forward tid %llu to mds%d - old seq %d <= %d\n",
2389 tid, next_mds, req->r_num_fwd, fwd_seq);
2390 } else {
2391 /* resend. forward race not possible; mds would drop */
2392 dout("forward tid %llu to mds%d (we resend)\n", tid, next_mds);
2393 BUG_ON(req->r_err);
2394 BUG_ON(req->r_got_result);
2395 req->r_num_fwd = fwd_seq;
2396 req->r_resend_mds = next_mds;
2397 put_request_session(req);
2398 __do_request(mdsc, req);
2399 }
2400 ceph_mdsc_put_request(req);
2401 out:
2402 mutex_unlock(&mdsc->mutex);
2403 return;
2404
2405 bad:
2406 pr_err("mdsc_handle_forward decode error err=%d\n", err);
2407 }
2408
2409 /*
2410 * handle a mds session control message
2411 */
2412 static void handle_session(struct ceph_mds_session *session,
2413 struct ceph_msg *msg)
2414 {
2415 struct ceph_mds_client *mdsc = session->s_mdsc;
2416 u32 op;
2417 u64 seq;
2418 int mds = session->s_mds;
2419 struct ceph_mds_session_head *h = msg->front.iov_base;
2420 int wake = 0;
2421
2422 /* decode */
2423 if (msg->front.iov_len != sizeof(*h))
2424 goto bad;
2425 op = le32_to_cpu(h->op);
2426 seq = le64_to_cpu(h->seq);
2427
2428 mutex_lock(&mdsc->mutex);
2429 if (op == CEPH_SESSION_CLOSE)
2430 __unregister_session(mdsc, session);
2431 /* FIXME: this ttl calculation is generous */
2432 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2433 mutex_unlock(&mdsc->mutex);
2434
2435 mutex_lock(&session->s_mutex);
2436
2437 dout("handle_session mds%d %s %p state %s seq %llu\n",
2438 mds, ceph_session_op_name(op), session,
2439 session_state_name(session->s_state), seq);
2440
2441 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2442 session->s_state = CEPH_MDS_SESSION_OPEN;
2443 pr_info("mds%d came back\n", session->s_mds);
2444 }
2445
2446 switch (op) {
2447 case CEPH_SESSION_OPEN:
2448 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2449 pr_info("mds%d reconnect success\n", session->s_mds);
2450 session->s_state = CEPH_MDS_SESSION_OPEN;
2451 renewed_caps(mdsc, session, 0);
2452 wake = 1;
2453 if (mdsc->stopping)
2454 __close_session(mdsc, session);
2455 break;
2456
2457 case CEPH_SESSION_RENEWCAPS:
2458 if (session->s_renew_seq == seq)
2459 renewed_caps(mdsc, session, 1);
2460 break;
2461
2462 case CEPH_SESSION_CLOSE:
2463 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2464 pr_info("mds%d reconnect denied\n", session->s_mds);
2465 remove_session_caps(session);
2466 wake = 1; /* for good measure */
2467 wake_up_all(&mdsc->session_close_wq);
2468 kick_requests(mdsc, mds);
2469 break;
2470
2471 case CEPH_SESSION_STALE:
2472 pr_info("mds%d caps went stale, renewing\n",
2473 session->s_mds);
2474 spin_lock(&session->s_gen_ttl_lock);
2475 session->s_cap_gen++;
2476 session->s_cap_ttl = jiffies - 1;
2477 spin_unlock(&session->s_gen_ttl_lock);
2478 send_renew_caps(mdsc, session);
2479 break;
2480
2481 case CEPH_SESSION_RECALL_STATE:
2482 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2483 break;
2484
2485 case CEPH_SESSION_FLUSHMSG:
2486 send_flushmsg_ack(mdsc, session, seq);
2487 break;
2488
2489 default:
2490 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2491 WARN_ON(1);
2492 }
2493
2494 mutex_unlock(&session->s_mutex);
2495 if (wake) {
2496 mutex_lock(&mdsc->mutex);
2497 __wake_requests(mdsc, &session->s_waiting);
2498 mutex_unlock(&mdsc->mutex);
2499 }
2500 return;
2501
2502 bad:
2503 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2504 (int)msg->front.iov_len);
2505 ceph_msg_dump(msg);
2506 return;
2507 }
2508
2509
2510 /*
2511 * called under session->mutex.
2512 */
2513 static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2514 struct ceph_mds_session *session)
2515 {
2516 struct ceph_mds_request *req, *nreq;
2517 int err;
2518
2519 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2520
2521 mutex_lock(&mdsc->mutex);
2522 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2523 err = __prepare_send_request(mdsc, req, session->s_mds);
2524 if (!err) {
2525 ceph_msg_get(req->r_request);
2526 ceph_con_send(&session->s_con, req->r_request);
2527 }
2528 }
2529 mutex_unlock(&mdsc->mutex);
2530 }
2531
2532 /*
2533 * Encode information about a cap for a reconnect with the MDS.
2534 */
2535 static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2536 void *arg)
2537 {
2538 union {
2539 struct ceph_mds_cap_reconnect v2;
2540 struct ceph_mds_cap_reconnect_v1 v1;
2541 } rec;
2542 size_t reclen;
2543 struct ceph_inode_info *ci;
2544 struct ceph_reconnect_state *recon_state = arg;
2545 struct ceph_pagelist *pagelist = recon_state->pagelist;
2546 char *path;
2547 int pathlen, err;
2548 u64 pathbase;
2549 struct dentry *dentry;
2550
2551 ci = cap->ci;
2552
2553 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2554 inode, ceph_vinop(inode), cap, cap->cap_id,
2555 ceph_cap_string(cap->issued));
2556 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2557 if (err)
2558 return err;
2559
2560 dentry = d_find_alias(inode);
2561 if (dentry) {
2562 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2563 if (IS_ERR(path)) {
2564 err = PTR_ERR(path);
2565 goto out_dput;
2566 }
2567 } else {
2568 path = NULL;
2569 pathlen = 0;
2570 }
2571 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2572 if (err)
2573 goto out_free;
2574
2575 spin_lock(&ci->i_ceph_lock);
2576 cap->seq = 0; /* reset cap seq */
2577 cap->issue_seq = 0; /* and issue_seq */
2578 cap->mseq = 0; /* and migrate_seq */
2579 cap->cap_gen = cap->session->s_cap_gen;
2580
2581 if (recon_state->flock) {
2582 rec.v2.cap_id = cpu_to_le64(cap->cap_id);
2583 rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2584 rec.v2.issued = cpu_to_le32(cap->issued);
2585 rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2586 rec.v2.pathbase = cpu_to_le64(pathbase);
2587 rec.v2.flock_len = 0;
2588 reclen = sizeof(rec.v2);
2589 } else {
2590 rec.v1.cap_id = cpu_to_le64(cap->cap_id);
2591 rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2592 rec.v1.issued = cpu_to_le32(cap->issued);
2593 rec.v1.size = cpu_to_le64(inode->i_size);
2594 ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
2595 ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
2596 rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2597 rec.v1.pathbase = cpu_to_le64(pathbase);
2598 reclen = sizeof(rec.v1);
2599 }
2600 spin_unlock(&ci->i_ceph_lock);
2601
2602 if (recon_state->flock) {
2603 int num_fcntl_locks, num_flock_locks;
2604 struct ceph_filelock *flocks;
2605
2606 encode_again:
2607 spin_lock(&inode->i_lock);
2608 ceph_count_locks(inode, &num_fcntl_locks, &num_flock_locks);
2609 spin_unlock(&inode->i_lock);
2610 flocks = kmalloc((num_fcntl_locks+num_flock_locks) *
2611 sizeof(struct ceph_filelock), GFP_NOFS);
2612 if (!flocks) {
2613 err = -ENOMEM;
2614 goto out_free;
2615 }
2616 spin_lock(&inode->i_lock);
2617 err = ceph_encode_locks_to_buffer(inode, flocks,
2618 num_fcntl_locks,
2619 num_flock_locks);
2620 spin_unlock(&inode->i_lock);
2621 if (err) {
2622 kfree(flocks);
2623 if (err == -ENOSPC)
2624 goto encode_again;
2625 goto out_free;
2626 }
2627 /*
2628 * number of encoded locks is stable, so copy to pagelist
2629 */
2630 rec.v2.flock_len = cpu_to_le32(2*sizeof(u32) +
2631 (num_fcntl_locks+num_flock_locks) *
2632 sizeof(struct ceph_filelock));
2633 err = ceph_pagelist_append(pagelist, &rec, reclen);
2634 if (!err)
2635 err = ceph_locks_to_pagelist(flocks, pagelist,
2636 num_fcntl_locks,
2637 num_flock_locks);
2638 kfree(flocks);
2639 } else {
2640 err = ceph_pagelist_append(pagelist, &rec, reclen);
2641 }
2642
2643 recon_state->nr_caps++;
2644 out_free:
2645 kfree(path);
2646 out_dput:
2647 dput(dentry);
2648 return err;
2649 }
2650
2651
2652 /*
2653 * If an MDS fails and recovers, clients need to reconnect in order to
2654 * reestablish shared state. This includes all caps issued through
2655 * this session _and_ the snap_realm hierarchy. Because it's not
2656 * clear which snap realms the mds cares about, we send everything we
2657 * know about.. that ensures we'll then get any new info the
2658 * recovering MDS might have.
2659 *
2660 * This is a relatively heavyweight operation, but it's rare.
2661 *
2662 * called with mdsc->mutex held.
2663 */
2664 static void send_mds_reconnect(struct ceph_mds_client *mdsc,
2665 struct ceph_mds_session *session)
2666 {
2667 struct ceph_msg *reply;
2668 struct rb_node *p;
2669 int mds = session->s_mds;
2670 int err = -ENOMEM;
2671 int s_nr_caps;
2672 struct ceph_pagelist *pagelist;
2673 struct ceph_reconnect_state recon_state;
2674
2675 pr_info("mds%d reconnect start\n", mds);
2676
2677 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2678 if (!pagelist)
2679 goto fail_nopagelist;
2680 ceph_pagelist_init(pagelist);
2681
2682 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS, false);
2683 if (!reply)
2684 goto fail_nomsg;
2685
2686 mutex_lock(&session->s_mutex);
2687 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2688 session->s_seq = 0;
2689
2690 ceph_con_close(&session->s_con);
2691 ceph_con_open(&session->s_con,
2692 CEPH_ENTITY_TYPE_MDS, mds,
2693 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2694
2695 /* replay unsafe requests */
2696 replay_unsafe_requests(mdsc, session);
2697
2698 down_read(&mdsc->snap_rwsem);
2699
2700 dout("session %p state %s\n", session,
2701 session_state_name(session->s_state));
2702
2703 spin_lock(&session->s_gen_ttl_lock);
2704 session->s_cap_gen++;
2705 spin_unlock(&session->s_gen_ttl_lock);
2706
2707 spin_lock(&session->s_cap_lock);
2708 /*
2709 * notify __ceph_remove_cap() that we are composing cap reconnect.
2710 * If a cap get released before being added to the cap reconnect,
2711 * __ceph_remove_cap() should skip queuing cap release.
2712 */
2713 session->s_cap_reconnect = 1;
2714 /* drop old cap expires; we're about to reestablish that state */
2715 discard_cap_releases(mdsc, session);
2716 spin_unlock(&session->s_cap_lock);
2717
2718 /* traverse this session's caps */
2719 s_nr_caps = session->s_nr_caps;
2720 err = ceph_pagelist_encode_32(pagelist, s_nr_caps);
2721 if (err)
2722 goto fail;
2723
2724 recon_state.nr_caps = 0;
2725 recon_state.pagelist = pagelist;
2726 recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK;
2727 err = iterate_session_caps(session, encode_caps_cb, &recon_state);
2728 if (err < 0)
2729 goto fail;
2730
2731 spin_lock(&session->s_cap_lock);
2732 session->s_cap_reconnect = 0;
2733 spin_unlock(&session->s_cap_lock);
2734
2735 /*
2736 * snaprealms. we provide mds with the ino, seq (version), and
2737 * parent for all of our realms. If the mds has any newer info,
2738 * it will tell us.
2739 */
2740 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2741 struct ceph_snap_realm *realm =
2742 rb_entry(p, struct ceph_snap_realm, node);
2743 struct ceph_mds_snaprealm_reconnect sr_rec;
2744
2745 dout(" adding snap realm %llx seq %lld parent %llx\n",
2746 realm->ino, realm->seq, realm->parent_ino);
2747 sr_rec.ino = cpu_to_le64(realm->ino);
2748 sr_rec.seq = cpu_to_le64(realm->seq);
2749 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2750 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2751 if (err)
2752 goto fail;
2753 }
2754
2755 if (recon_state.flock)
2756 reply->hdr.version = cpu_to_le16(2);
2757
2758 /* raced with cap release? */
2759 if (s_nr_caps != recon_state.nr_caps) {
2760 struct page *page = list_first_entry(&pagelist->head,
2761 struct page, lru);
2762 __le32 *addr = kmap_atomic(page);
2763 *addr = cpu_to_le32(recon_state.nr_caps);
2764 kunmap_atomic(addr);
2765 }
2766
2767 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2768 ceph_msg_data_add_pagelist(reply, pagelist);
2769 ceph_con_send(&session->s_con, reply);
2770
2771 mutex_unlock(&session->s_mutex);
2772
2773 mutex_lock(&mdsc->mutex);
2774 __wake_requests(mdsc, &session->s_waiting);
2775 mutex_unlock(&mdsc->mutex);
2776
2777 up_read(&mdsc->snap_rwsem);
2778 return;
2779
2780 fail:
2781 ceph_msg_put(reply);
2782 up_read(&mdsc->snap_rwsem);
2783 mutex_unlock(&session->s_mutex);
2784 fail_nomsg:
2785 ceph_pagelist_release(pagelist);
2786 kfree(pagelist);
2787 fail_nopagelist:
2788 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
2789 return;
2790 }
2791
2792
2793 /*
2794 * compare old and new mdsmaps, kicking requests
2795 * and closing out old connections as necessary
2796 *
2797 * called under mdsc->mutex.
2798 */
2799 static void check_new_map(struct ceph_mds_client *mdsc,
2800 struct ceph_mdsmap *newmap,
2801 struct ceph_mdsmap *oldmap)
2802 {
2803 int i;
2804 int oldstate, newstate;
2805 struct ceph_mds_session *s;
2806
2807 dout("check_new_map new %u old %u\n",
2808 newmap->m_epoch, oldmap->m_epoch);
2809
2810 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2811 if (mdsc->sessions[i] == NULL)
2812 continue;
2813 s = mdsc->sessions[i];
2814 oldstate = ceph_mdsmap_get_state(oldmap, i);
2815 newstate = ceph_mdsmap_get_state(newmap, i);
2816
2817 dout("check_new_map mds%d state %s%s -> %s%s (session %s)\n",
2818 i, ceph_mds_state_name(oldstate),
2819 ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "",
2820 ceph_mds_state_name(newstate),
2821 ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
2822 session_state_name(s->s_state));
2823
2824 if (i >= newmap->m_max_mds ||
2825 memcmp(ceph_mdsmap_get_addr(oldmap, i),
2826 ceph_mdsmap_get_addr(newmap, i),
2827 sizeof(struct ceph_entity_addr))) {
2828 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2829 /* the session never opened, just close it
2830 * out now */
2831 __wake_requests(mdsc, &s->s_waiting);
2832 __unregister_session(mdsc, s);
2833 } else {
2834 /* just close it */
2835 mutex_unlock(&mdsc->mutex);
2836 mutex_lock(&s->s_mutex);
2837 mutex_lock(&mdsc->mutex);
2838 ceph_con_close(&s->s_con);
2839 mutex_unlock(&s->s_mutex);
2840 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2841 }
2842
2843 /* kick any requests waiting on the recovering mds */
2844 kick_requests(mdsc, i);
2845 } else if (oldstate == newstate) {
2846 continue; /* nothing new with this mds */
2847 }
2848
2849 /*
2850 * send reconnect?
2851 */
2852 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2853 newstate >= CEPH_MDS_STATE_RECONNECT) {
2854 mutex_unlock(&mdsc->mutex);
2855 send_mds_reconnect(mdsc, s);
2856 mutex_lock(&mdsc->mutex);
2857 }
2858
2859 /*
2860 * kick request on any mds that has gone active.
2861 */
2862 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2863 newstate >= CEPH_MDS_STATE_ACTIVE) {
2864 if (oldstate != CEPH_MDS_STATE_CREATING &&
2865 oldstate != CEPH_MDS_STATE_STARTING)
2866 pr_info("mds%d recovery completed\n", s->s_mds);
2867 kick_requests(mdsc, i);
2868 ceph_kick_flushing_caps(mdsc, s);
2869 wake_up_session_caps(s, 1);
2870 }
2871 }
2872
2873 for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
2874 s = mdsc->sessions[i];
2875 if (!s)
2876 continue;
2877 if (!ceph_mdsmap_is_laggy(newmap, i))
2878 continue;
2879 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2880 s->s_state == CEPH_MDS_SESSION_HUNG ||
2881 s->s_state == CEPH_MDS_SESSION_CLOSING) {
2882 dout(" connecting to export targets of laggy mds%d\n",
2883 i);
2884 __open_export_target_sessions(mdsc, s);
2885 }
2886 }
2887 }
2888
2889
2890
2891 /*
2892 * leases
2893 */
2894
2895 /*
2896 * caller must hold session s_mutex, dentry->d_lock
2897 */
2898 void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2899 {
2900 struct ceph_dentry_info *di = ceph_dentry(dentry);
2901
2902 ceph_put_mds_session(di->lease_session);
2903 di->lease_session = NULL;
2904 }
2905
2906 static void handle_lease(struct ceph_mds_client *mdsc,
2907 struct ceph_mds_session *session,
2908 struct ceph_msg *msg)
2909 {
2910 struct super_block *sb = mdsc->fsc->sb;
2911 struct inode *inode;
2912 struct dentry *parent, *dentry;
2913 struct ceph_dentry_info *di;
2914 int mds = session->s_mds;
2915 struct ceph_mds_lease *h = msg->front.iov_base;
2916 u32 seq;
2917 struct ceph_vino vino;
2918 struct qstr dname;
2919 int release = 0;
2920
2921 dout("handle_lease from mds%d\n", mds);
2922
2923 /* decode */
2924 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2925 goto bad;
2926 vino.ino = le64_to_cpu(h->ino);
2927 vino.snap = CEPH_NOSNAP;
2928 seq = le32_to_cpu(h->seq);
2929 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2930 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2931 if (dname.len != get_unaligned_le32(h+1))
2932 goto bad;
2933
2934 mutex_lock(&session->s_mutex);
2935 session->s_seq++;
2936
2937 /* lookup inode */
2938 inode = ceph_find_inode(sb, vino);
2939 dout("handle_lease %s, ino %llx %p %.*s\n",
2940 ceph_lease_op_name(h->action), vino.ino, inode,
2941 dname.len, dname.name);
2942 if (inode == NULL) {
2943 dout("handle_lease no inode %llx\n", vino.ino);
2944 goto release;
2945 }
2946
2947 /* dentry */
2948 parent = d_find_alias(inode);
2949 if (!parent) {
2950 dout("no parent dentry on inode %p\n", inode);
2951 WARN_ON(1);
2952 goto release; /* hrm... */
2953 }
2954 dname.hash = full_name_hash(dname.name, dname.len);
2955 dentry = d_lookup(parent, &dname);
2956 dput(parent);
2957 if (!dentry)
2958 goto release;
2959
2960 spin_lock(&dentry->d_lock);
2961 di = ceph_dentry(dentry);
2962 switch (h->action) {
2963 case CEPH_MDS_LEASE_REVOKE:
2964 if (di->lease_session == session) {
2965 if (ceph_seq_cmp(di->lease_seq, seq) > 0)
2966 h->seq = cpu_to_le32(di->lease_seq);
2967 __ceph_mdsc_drop_dentry_lease(dentry);
2968 }
2969 release = 1;
2970 break;
2971
2972 case CEPH_MDS_LEASE_RENEW:
2973 if (di->lease_session == session &&
2974 di->lease_gen == session->s_cap_gen &&
2975 di->lease_renew_from &&
2976 di->lease_renew_after == 0) {
2977 unsigned long duration =
2978 le32_to_cpu(h->duration_ms) * HZ / 1000;
2979
2980 di->lease_seq = seq;
2981 dentry->d_time = di->lease_renew_from + duration;
2982 di->lease_renew_after = di->lease_renew_from +
2983 (duration >> 1);
2984 di->lease_renew_from = 0;
2985 }
2986 break;
2987 }
2988 spin_unlock(&dentry->d_lock);
2989 dput(dentry);
2990
2991 if (!release)
2992 goto out;
2993
2994 release:
2995 /* let's just reuse the same message */
2996 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2997 ceph_msg_get(msg);
2998 ceph_con_send(&session->s_con, msg);
2999
3000 out:
3001 iput(inode);
3002 mutex_unlock(&session->s_mutex);
3003 return;
3004
3005 bad:
3006 pr_err("corrupt lease message\n");
3007 ceph_msg_dump(msg);
3008 }
3009
3010 void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
3011 struct inode *inode,
3012 struct dentry *dentry, char action,
3013 u32 seq)
3014 {
3015 struct ceph_msg *msg;
3016 struct ceph_mds_lease *lease;
3017 int len = sizeof(*lease) + sizeof(u32);
3018 int dnamelen = 0;
3019
3020 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
3021 inode, dentry, ceph_lease_op_name(action), session->s_mds);
3022 dnamelen = dentry->d_name.len;
3023 len += dnamelen;
3024
3025 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false);
3026 if (!msg)
3027 return;
3028 lease = msg->front.iov_base;
3029 lease->action = action;
3030 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
3031 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
3032 lease->seq = cpu_to_le32(seq);
3033 put_unaligned_le32(dnamelen, lease + 1);
3034 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
3035
3036 /*
3037 * if this is a preemptive lease RELEASE, no need to
3038 * flush request stream, since the actual request will
3039 * soon follow.
3040 */
3041 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
3042
3043 ceph_con_send(&session->s_con, msg);
3044 }
3045
3046 /*
3047 * Preemptively release a lease we expect to invalidate anyway.
3048 * Pass @inode always, @dentry is optional.
3049 */
3050 void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
3051 struct dentry *dentry)
3052 {
3053 struct ceph_dentry_info *di;
3054 struct ceph_mds_session *session;
3055 u32 seq;
3056
3057 BUG_ON(inode == NULL);
3058 BUG_ON(dentry == NULL);
3059
3060 /* is dentry lease valid? */
3061 spin_lock(&dentry->d_lock);
3062 di = ceph_dentry(dentry);
3063 if (!di || !di->lease_session ||
3064 di->lease_session->s_mds < 0 ||
3065 di->lease_gen != di->lease_session->s_cap_gen ||
3066 !time_before(jiffies, dentry->d_time)) {
3067 dout("lease_release inode %p dentry %p -- "
3068 "no lease\n",
3069 inode, dentry);
3070 spin_unlock(&dentry->d_lock);
3071 return;
3072 }
3073
3074 /* we do have a lease on this dentry; note mds and seq */
3075 session = ceph_get_mds_session(di->lease_session);
3076 seq = di->lease_seq;
3077 __ceph_mdsc_drop_dentry_lease(dentry);
3078 spin_unlock(&dentry->d_lock);
3079
3080 dout("lease_release inode %p dentry %p to mds%d\n",
3081 inode, dentry, session->s_mds);
3082 ceph_mdsc_lease_send_msg(session, inode, dentry,
3083 CEPH_MDS_LEASE_RELEASE, seq);
3084 ceph_put_mds_session(session);
3085 }
3086
3087 /*
3088 * drop all leases (and dentry refs) in preparation for umount
3089 */
3090 static void drop_leases(struct ceph_mds_client *mdsc)
3091 {
3092 int i;
3093
3094 dout("drop_leases\n");
3095 mutex_lock(&mdsc->mutex);
3096 for (i = 0; i < mdsc->max_sessions; i++) {
3097 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
3098 if (!s)
3099 continue;
3100 mutex_unlock(&mdsc->mutex);
3101 mutex_lock(&s->s_mutex);
3102 mutex_unlock(&s->s_mutex);
3103 ceph_put_mds_session(s);
3104 mutex_lock(&mdsc->mutex);
3105 }
3106 mutex_unlock(&mdsc->mutex);
3107 }
3108
3109
3110
3111 /*
3112 * delayed work -- periodically trim expired leases, renew caps with mds
3113 */
3114 static void schedule_delayed(struct ceph_mds_client *mdsc)
3115 {
3116 int delay = 5;
3117 unsigned hz = round_jiffies_relative(HZ * delay);
3118 schedule_delayed_work(&mdsc->delayed_work, hz);
3119 }
3120
3121 static void delayed_work(struct work_struct *work)
3122 {
3123 int i;
3124 struct ceph_mds_client *mdsc =
3125 container_of(work, struct ceph_mds_client, delayed_work.work);
3126 int renew_interval;
3127 int renew_caps;
3128
3129 dout("mdsc delayed_work\n");
3130 ceph_check_delayed_caps(mdsc);
3131
3132 mutex_lock(&mdsc->mutex);
3133 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
3134 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
3135 mdsc->last_renew_caps);
3136 if (renew_caps)
3137 mdsc->last_renew_caps = jiffies;
3138
3139 for (i = 0; i < mdsc->max_sessions; i++) {
3140 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
3141 if (s == NULL)
3142 continue;
3143 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
3144 dout("resending session close request for mds%d\n",
3145 s->s_mds);
3146 request_close_session(mdsc, s);
3147 ceph_put_mds_session(s);
3148 continue;
3149 }
3150 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
3151 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
3152 s->s_state = CEPH_MDS_SESSION_HUNG;
3153 pr_info("mds%d hung\n", s->s_mds);
3154 }
3155 }
3156 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
3157 /* this mds is failed or recovering, just wait */
3158 ceph_put_mds_session(s);
3159 continue;
3160 }
3161 mutex_unlock(&mdsc->mutex);
3162
3163 mutex_lock(&s->s_mutex);
3164 if (renew_caps)
3165 send_renew_caps(mdsc, s);
3166 else
3167 ceph_con_keepalive(&s->s_con);
3168 ceph_add_cap_releases(mdsc, s);
3169 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
3170 s->s_state == CEPH_MDS_SESSION_HUNG)
3171 ceph_send_cap_releases(mdsc, s);
3172 mutex_unlock(&s->s_mutex);
3173 ceph_put_mds_session(s);
3174
3175 mutex_lock(&mdsc->mutex);
3176 }
3177 mutex_unlock(&mdsc->mutex);
3178
3179 schedule_delayed(mdsc);
3180 }
3181
3182 int ceph_mdsc_init(struct ceph_fs_client *fsc)
3183
3184 {
3185 struct ceph_mds_client *mdsc;
3186
3187 mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS);
3188 if (!mdsc)
3189 return -ENOMEM;
3190 mdsc->fsc = fsc;
3191 fsc->mdsc = mdsc;
3192 mutex_init(&mdsc->mutex);
3193 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
3194 if (mdsc->mdsmap == NULL) {
3195 kfree(mdsc);
3196 return -ENOMEM;
3197 }
3198
3199 init_completion(&mdsc->safe_umount_waiters);
3200 init_waitqueue_head(&mdsc->session_close_wq);
3201 INIT_LIST_HEAD(&mdsc->waiting_for_map);
3202 mdsc->sessions = NULL;
3203 mdsc->max_sessions = 0;
3204 mdsc->stopping = 0;
3205 init_rwsem(&mdsc->snap_rwsem);
3206 mdsc->snap_realms = RB_ROOT;
3207 INIT_LIST_HEAD(&mdsc->snap_empty);
3208 spin_lock_init(&mdsc->snap_empty_lock);
3209 mdsc->last_tid = 0;
3210 mdsc->request_tree = RB_ROOT;
3211 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
3212 mdsc->last_renew_caps = jiffies;
3213 INIT_LIST_HEAD(&mdsc->cap_delay_list);
3214 spin_lock_init(&mdsc->cap_delay_lock);
3215 INIT_LIST_HEAD(&mdsc->snap_flush_list);
3216 spin_lock_init(&mdsc->snap_flush_lock);
3217 mdsc->cap_flush_seq = 0;
3218 INIT_LIST_HEAD(&mdsc->cap_dirty);
3219 INIT_LIST_HEAD(&mdsc->cap_dirty_migrating);
3220 mdsc->num_cap_flushing = 0;
3221 spin_lock_init(&mdsc->cap_dirty_lock);
3222 init_waitqueue_head(&mdsc->cap_flushing_wq);
3223 spin_lock_init(&mdsc->dentry_lru_lock);
3224 INIT_LIST_HEAD(&mdsc->dentry_lru);
3225
3226 ceph_caps_init(mdsc);
3227 ceph_adjust_min_caps(mdsc, fsc->min_caps);
3228
3229 return 0;
3230 }
3231
3232 /*
3233 * Wait for safe replies on open mds requests. If we time out, drop
3234 * all requests from the tree to avoid dangling dentry refs.
3235 */
3236 static void wait_requests(struct ceph_mds_client *mdsc)
3237 {
3238 struct ceph_mds_request *req;
3239 struct ceph_fs_client *fsc = mdsc->fsc;
3240
3241 mutex_lock(&mdsc->mutex);
3242 if (__get_oldest_req(mdsc)) {
3243 mutex_unlock(&mdsc->mutex);
3244
3245 dout("wait_requests waiting for requests\n");
3246 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
3247 fsc->client->options->mount_timeout * HZ);
3248
3249 /* tear down remaining requests */
3250 mutex_lock(&mdsc->mutex);
3251 while ((req = __get_oldest_req(mdsc))) {
3252 dout("wait_requests timed out on tid %llu\n",
3253 req->r_tid);
3254 __unregister_request(mdsc, req);
3255 }
3256 }
3257 mutex_unlock(&mdsc->mutex);
3258 dout("wait_requests done\n");
3259 }
3260
3261 /*
3262 * called before mount is ro, and before dentries are torn down.
3263 * (hmm, does this still race with new lookups?)
3264 */
3265 void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
3266 {
3267 dout("pre_umount\n");
3268 mdsc->stopping = 1;
3269
3270 drop_leases(mdsc);
3271 ceph_flush_dirty_caps(mdsc);
3272 wait_requests(mdsc);
3273
3274 /*
3275 * wait for reply handlers to drop their request refs and
3276 * their inode/dcache refs
3277 */
3278 ceph_msgr_flush();
3279 }
3280
3281 /*
3282 * wait for all write mds requests to flush.
3283 */
3284 static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
3285 {
3286 struct ceph_mds_request *req = NULL, *nextreq;
3287 struct rb_node *n;
3288
3289 mutex_lock(&mdsc->mutex);
3290 dout("wait_unsafe_requests want %lld\n", want_tid);
3291 restart:
3292 req = __get_oldest_req(mdsc);
3293 while (req && req->r_tid <= want_tid) {
3294 /* find next request */
3295 n = rb_next(&req->r_node);
3296 if (n)
3297 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
3298 else
3299 nextreq = NULL;
3300 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
3301 /* write op */
3302 ceph_mdsc_get_request(req);
3303 if (nextreq)
3304 ceph_mdsc_get_request(nextreq);
3305 mutex_unlock(&mdsc->mutex);
3306 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
3307 req->r_tid, want_tid);
3308 wait_for_completion(&req->r_safe_completion);
3309 mutex_lock(&mdsc->mutex);
3310 ceph_mdsc_put_request(req);
3311 if (!nextreq)
3312 break; /* next dne before, so we're done! */
3313 if (RB_EMPTY_NODE(&nextreq->r_node)) {
3314 /* next request was removed from tree */
3315 ceph_mdsc_put_request(nextreq);
3316 goto restart;
3317 }
3318 ceph_mdsc_put_request(nextreq); /* won't go away */
3319 }
3320 req = nextreq;
3321 }
3322 mutex_unlock(&mdsc->mutex);
3323 dout("wait_unsafe_requests done\n");
3324 }
3325
3326 void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
3327 {
3328 u64 want_tid, want_flush;
3329
3330 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3331 return;
3332
3333 dout("sync\n");
3334 mutex_lock(&mdsc->mutex);
3335 want_tid = mdsc->last_tid;
3336 want_flush = mdsc->cap_flush_seq;
3337 mutex_unlock(&mdsc->mutex);
3338 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
3339
3340 ceph_flush_dirty_caps(mdsc);
3341
3342 wait_unsafe_requests(mdsc, want_tid);
3343 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
3344 }
3345
3346 /*
3347 * true if all sessions are closed, or we force unmount
3348 */
3349 static bool done_closing_sessions(struct ceph_mds_client *mdsc)
3350 {
3351 int i, n = 0;
3352
3353 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3354 return true;
3355
3356 mutex_lock(&mdsc->mutex);
3357 for (i = 0; i < mdsc->max_sessions; i++)
3358 if (mdsc->sessions[i])
3359 n++;
3360 mutex_unlock(&mdsc->mutex);
3361 return n == 0;
3362 }
3363
3364 /*
3365 * called after sb is ro.
3366 */
3367 void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
3368 {
3369 struct ceph_mds_session *session;
3370 int i;
3371 struct ceph_fs_client *fsc = mdsc->fsc;
3372 unsigned long timeout = fsc->client->options->mount_timeout * HZ;
3373
3374 dout("close_sessions\n");
3375
3376 /* close sessions */
3377 mutex_lock(&mdsc->mutex);
3378 for (i = 0; i < mdsc->max_sessions; i++) {
3379 session = __ceph_lookup_mds_session(mdsc, i);
3380 if (!session)
3381 continue;
3382 mutex_unlock(&mdsc->mutex);
3383 mutex_lock(&session->s_mutex);
3384 __close_session(mdsc, session);
3385 mutex_unlock(&session->s_mutex);
3386 ceph_put_mds_session(session);
3387 mutex_lock(&mdsc->mutex);
3388 }
3389 mutex_unlock(&mdsc->mutex);
3390
3391 dout("waiting for sessions to close\n");
3392 wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc),
3393 timeout);
3394
3395 /* tear down remaining sessions */
3396 mutex_lock(&mdsc->mutex);
3397 for (i = 0; i < mdsc->max_sessions; i++) {
3398 if (mdsc->sessions[i]) {
3399 session = get_session(mdsc->sessions[i]);
3400 __unregister_session(mdsc, session);
3401 mutex_unlock(&mdsc->mutex);
3402 mutex_lock(&session->s_mutex);
3403 remove_session_caps(session);
3404 mutex_unlock(&session->s_mutex);
3405 ceph_put_mds_session(session);
3406 mutex_lock(&mdsc->mutex);
3407 }
3408 }
3409 WARN_ON(!list_empty(&mdsc->cap_delay_list));
3410 mutex_unlock(&mdsc->mutex);
3411
3412 ceph_cleanup_empty_realms(mdsc);
3413
3414 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3415
3416 dout("stopped\n");
3417 }
3418
3419 static void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
3420 {
3421 dout("stop\n");
3422 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3423 if (mdsc->mdsmap)
3424 ceph_mdsmap_destroy(mdsc->mdsmap);
3425 kfree(mdsc->sessions);
3426 ceph_caps_finalize(mdsc);
3427 }
3428
3429 void ceph_mdsc_destroy(struct ceph_fs_client *fsc)
3430 {
3431 struct ceph_mds_client *mdsc = fsc->mdsc;
3432
3433 dout("mdsc_destroy %p\n", mdsc);
3434 ceph_mdsc_stop(mdsc);
3435
3436 /* flush out any connection work with references to us */
3437 ceph_msgr_flush();
3438
3439 fsc->mdsc = NULL;
3440 kfree(mdsc);
3441 dout("mdsc_destroy %p done\n", mdsc);
3442 }
3443
3444
3445 /*
3446 * handle mds map update.
3447 */
3448 void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3449 {
3450 u32 epoch;
3451 u32 maplen;
3452 void *p = msg->front.iov_base;
3453 void *end = p + msg->front.iov_len;
3454 struct ceph_mdsmap *newmap, *oldmap;
3455 struct ceph_fsid fsid;
3456 int err = -EINVAL;
3457
3458 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
3459 ceph_decode_copy(&p, &fsid, sizeof(fsid));
3460 if (ceph_check_fsid(mdsc->fsc->client, &fsid) < 0)
3461 return;
3462 epoch = ceph_decode_32(&p);
3463 maplen = ceph_decode_32(&p);
3464 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
3465
3466 /* do we need it? */
3467 ceph_monc_got_mdsmap(&mdsc->fsc->client->monc, epoch);
3468 mutex_lock(&mdsc->mutex);
3469 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
3470 dout("handle_map epoch %u <= our %u\n",
3471 epoch, mdsc->mdsmap->m_epoch);
3472 mutex_unlock(&mdsc->mutex);
3473 return;
3474 }
3475
3476 newmap = ceph_mdsmap_decode(&p, end);
3477 if (IS_ERR(newmap)) {
3478 err = PTR_ERR(newmap);
3479 goto bad_unlock;
3480 }
3481
3482 /* swap into place */
3483 if (mdsc->mdsmap) {
3484 oldmap = mdsc->mdsmap;
3485 mdsc->mdsmap = newmap;
3486 check_new_map(mdsc, newmap, oldmap);
3487 ceph_mdsmap_destroy(oldmap);
3488 } else {
3489 mdsc->mdsmap = newmap; /* first mds map */
3490 }
3491 mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
3492
3493 __wake_requests(mdsc, &mdsc->waiting_for_map);
3494
3495 mutex_unlock(&mdsc->mutex);
3496 schedule_delayed(mdsc);
3497 return;
3498
3499 bad_unlock:
3500 mutex_unlock(&mdsc->mutex);
3501 bad:
3502 pr_err("error decoding mdsmap %d\n", err);
3503 return;
3504 }
3505
3506 static struct ceph_connection *con_get(struct ceph_connection *con)
3507 {
3508 struct ceph_mds_session *s = con->private;
3509
3510 if (get_session(s)) {
3511 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
3512 return con;
3513 }
3514 dout("mdsc con_get %p FAIL\n", s);
3515 return NULL;
3516 }
3517
3518 static void con_put(struct ceph_connection *con)
3519 {
3520 struct ceph_mds_session *s = con->private;
3521
3522 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref) - 1);
3523 ceph_put_mds_session(s);
3524 }
3525
3526 /*
3527 * if the client is unresponsive for long enough, the mds will kill
3528 * the session entirely.
3529 */
3530 static void peer_reset(struct ceph_connection *con)
3531 {
3532 struct ceph_mds_session *s = con->private;
3533 struct ceph_mds_client *mdsc = s->s_mdsc;
3534
3535 pr_warn("mds%d closed our session\n", s->s_mds);
3536 send_mds_reconnect(mdsc, s);
3537 }
3538
3539 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
3540 {
3541 struct ceph_mds_session *s = con->private;
3542 struct ceph_mds_client *mdsc = s->s_mdsc;
3543 int type = le16_to_cpu(msg->hdr.type);
3544
3545 mutex_lock(&mdsc->mutex);
3546 if (__verify_registered_session(mdsc, s) < 0) {
3547 mutex_unlock(&mdsc->mutex);
3548 goto out;
3549 }
3550 mutex_unlock(&mdsc->mutex);
3551
3552 switch (type) {
3553 case CEPH_MSG_MDS_MAP:
3554 ceph_mdsc_handle_map(mdsc, msg);
3555 break;
3556 case CEPH_MSG_CLIENT_SESSION:
3557 handle_session(s, msg);
3558 break;
3559 case CEPH_MSG_CLIENT_REPLY:
3560 handle_reply(s, msg);
3561 break;
3562 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
3563 handle_forward(mdsc, s, msg);
3564 break;
3565 case CEPH_MSG_CLIENT_CAPS:
3566 ceph_handle_caps(s, msg);
3567 break;
3568 case CEPH_MSG_CLIENT_SNAP:
3569 ceph_handle_snap(mdsc, s, msg);
3570 break;
3571 case CEPH_MSG_CLIENT_LEASE:
3572 handle_lease(mdsc, s, msg);
3573 break;
3574
3575 default:
3576 pr_err("received unknown message type %d %s\n", type,
3577 ceph_msg_type_name(type));
3578 }
3579 out:
3580 ceph_msg_put(msg);
3581 }
3582
3583 /*
3584 * authentication
3585 */
3586
3587 /*
3588 * Note: returned pointer is the address of a structure that's
3589 * managed separately. Caller must *not* attempt to free it.
3590 */
3591 static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con,
3592 int *proto, int force_new)
3593 {
3594 struct ceph_mds_session *s = con->private;
3595 struct ceph_mds_client *mdsc = s->s_mdsc;
3596 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3597 struct ceph_auth_handshake *auth = &s->s_auth;
3598
3599 if (force_new && auth->authorizer) {
3600 ceph_auth_destroy_authorizer(ac, auth->authorizer);
3601 auth->authorizer = NULL;
3602 }
3603 if (!auth->authorizer) {
3604 int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
3605 auth);
3606 if (ret)
3607 return ERR_PTR(ret);
3608 } else {
3609 int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
3610 auth);
3611 if (ret)
3612 return ERR_PTR(ret);
3613 }
3614 *proto = ac->protocol;
3615
3616 return auth;
3617 }
3618
3619
3620 static int verify_authorizer_reply(struct ceph_connection *con, int len)
3621 {
3622 struct ceph_mds_session *s = con->private;
3623 struct ceph_mds_client *mdsc = s->s_mdsc;
3624 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3625
3626 return ceph_auth_verify_authorizer_reply(ac, s->s_auth.authorizer, len);
3627 }
3628
3629 static int invalidate_authorizer(struct ceph_connection *con)
3630 {
3631 struct ceph_mds_session *s = con->private;
3632 struct ceph_mds_client *mdsc = s->s_mdsc;
3633 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3634
3635 ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3636
3637 return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
3638 }
3639
3640 static struct ceph_msg *mds_alloc_msg(struct ceph_connection *con,
3641 struct ceph_msg_header *hdr, int *skip)
3642 {
3643 struct ceph_msg *msg;
3644 int type = (int) le16_to_cpu(hdr->type);
3645 int front_len = (int) le32_to_cpu(hdr->front_len);
3646
3647 if (con->in_msg)
3648 return con->in_msg;
3649
3650 *skip = 0;
3651 msg = ceph_msg_new(type, front_len, GFP_NOFS, false);
3652 if (!msg) {
3653 pr_err("unable to allocate msg type %d len %d\n",
3654 type, front_len);
3655 return NULL;
3656 }
3657
3658 return msg;
3659 }
3660
3661 static const struct ceph_connection_operations mds_con_ops = {
3662 .get = con_get,
3663 .put = con_put,
3664 .dispatch = dispatch,
3665 .get_authorizer = get_authorizer,
3666 .verify_authorizer_reply = verify_authorizer_reply,
3667 .invalidate_authorizer = invalidate_authorizer,
3668 .peer_reset = peer_reset,
3669 .alloc_msg = mds_alloc_msg,
3670 };
3671
3672 /* eof */
Linux with added FPC-III support