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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / fs / ceph / mds_client.c
blob86c59e16ba74e459ad0c3f29743ace6663f29206
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/sched.h>
7 #include <linux/debugfs.h>
8 #include <linux/seq_file.h>
9
10 #include "super.h"
11 #include "mds_client.h"
12
13 #include <linux/ceph/messenger.h>
14 #include <linux/ceph/decode.h>
15 #include <linux/ceph/pagelist.h>
16 #include <linux/ceph/auth.h>
17 #include <linux/ceph/debugfs.h>
18
19 /*
20 * A cluster of MDS (metadata server) daemons is responsible for
21 * managing the file system namespace (the directory hierarchy and
22 * inodes) and for coordinating shared access to storage. Metadata is
23 * partitioning hierarchically across a number of servers, and that
24 * partition varies over time as the cluster adjusts the distribution
25 * in order to balance load.
26 *
27 * The MDS client is primarily responsible to managing synchronous
28 * metadata requests for operations like open, unlink, and so forth.
29 * If there is a MDS failure, we find out about it when we (possibly
30 * request and) receive a new MDS map, and can resubmit affected
31 * requests.
32 *
33 * For the most part, though, we take advantage of a lossless
34 * communications channel to the MDS, and do not need to worry about
35 * timing out or resubmitting requests.
36 *
37 * We maintain a stateful "session" with each MDS we interact with.
38 * Within each session, we sent periodic heartbeat messages to ensure
39 * any capabilities or leases we have been issues remain valid. If
40 * the session times out and goes stale, our leases and capabilities
41 * are no longer valid.
42 */
43
44 struct ceph_reconnect_state {
45 struct ceph_pagelist *pagelist;
46 bool flock;
47 };
48
49 static void __wake_requests(struct ceph_mds_client *mdsc,
50 struct list_head *head);
51
52 static const struct ceph_connection_operations mds_con_ops;
53
54
55 /*
56 * mds reply parsing
57 */
58
59 /*
60 * parse individual inode info
61 */
62 static int parse_reply_info_in(void **p, void *end,
63 struct ceph_mds_reply_info_in *info,
64 int features)
65 {
66 int err = -EIO;
67
68 info->in = *p;
69 *p += sizeof(struct ceph_mds_reply_inode) +
70 sizeof(*info->in->fragtree.splits) *
71 le32_to_cpu(info->in->fragtree.nsplits);
72
73 ceph_decode_32_safe(p, end, info->symlink_len, bad);
74 ceph_decode_need(p, end, info->symlink_len, bad);
75 info->symlink = *p;
76 *p += info->symlink_len;
77
78 if (features & CEPH_FEATURE_DIRLAYOUTHASH)
79 ceph_decode_copy_safe(p, end, &info->dir_layout,
80 sizeof(info->dir_layout), bad);
81 else
82 memset(&info->dir_layout, 0, sizeof(info->dir_layout));
83
84 ceph_decode_32_safe(p, end, info->xattr_len, bad);
85 ceph_decode_need(p, end, info->xattr_len, bad);
86 info->xattr_data = *p;
87 *p += info->xattr_len;
88 return 0;
89 bad:
90 return err;
91 }
92
93 /*
94 * parse a normal reply, which may contain a (dir+)dentry and/or a
95 * target inode.
96 */
97 static int parse_reply_info_trace(void **p, void *end,
98 struct ceph_mds_reply_info_parsed *info,
99 int features)
100 {
101 int err;
102
103 if (info->head->is_dentry) {
104 err = parse_reply_info_in(p, end, &info->diri, features);
105 if (err < 0)
106 goto out_bad;
107
108 if (unlikely(*p + sizeof(*info->dirfrag) > end))
109 goto bad;
110 info->dirfrag = *p;
111 *p += sizeof(*info->dirfrag) +
112 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
113 if (unlikely(*p > end))
114 goto bad;
115
116 ceph_decode_32_safe(p, end, info->dname_len, bad);
117 ceph_decode_need(p, end, info->dname_len, bad);
118 info->dname = *p;
119 *p += info->dname_len;
120 info->dlease = *p;
121 *p += sizeof(*info->dlease);
122 }
123
124 if (info->head->is_target) {
125 err = parse_reply_info_in(p, end, &info->targeti, features);
126 if (err < 0)
127 goto out_bad;
128 }
129
130 if (unlikely(*p != end))
131 goto bad;
132 return 0;
133
134 bad:
135 err = -EIO;
136 out_bad:
137 pr_err("problem parsing mds trace %d\n", err);
138 return err;
139 }
140
141 /*
142 * parse readdir results
143 */
144 static int parse_reply_info_dir(void **p, void *end,
145 struct ceph_mds_reply_info_parsed *info,
146 int features)
147 {
148 u32 num, i = 0;
149 int err;
150
151 info->dir_dir = *p;
152 if (*p + sizeof(*info->dir_dir) > end)
153 goto bad;
154 *p += sizeof(*info->dir_dir) +
155 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
156 if (*p > end)
157 goto bad;
158
159 ceph_decode_need(p, end, sizeof(num) + 2, bad);
160 num = ceph_decode_32(p);
161 info->dir_end = ceph_decode_8(p);
162 info->dir_complete = ceph_decode_8(p);
163 if (num == 0)
164 goto done;
165
166 /* alloc large array */
167 info->dir_nr = num;
168 info->dir_in = kcalloc(num, sizeof(*info->dir_in) +
169 sizeof(*info->dir_dname) +
170 sizeof(*info->dir_dname_len) +
171 sizeof(*info->dir_dlease),
172 GFP_NOFS);
173 if (info->dir_in == NULL) {
174 err = -ENOMEM;
175 goto out_bad;
176 }
177 info->dir_dname = (void *)(info->dir_in + num);
178 info->dir_dname_len = (void *)(info->dir_dname + num);
179 info->dir_dlease = (void *)(info->dir_dname_len + num);
180
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 int 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 extra results
236 */
237 static int parse_reply_info_extra(void **p, void *end,
238 struct ceph_mds_reply_info_parsed *info,
239 int features)
240 {
241 if (info->head->op == CEPH_MDS_OP_GETFILELOCK)
242 return parse_reply_info_filelock(p, end, info, features);
243 else
244 return parse_reply_info_dir(p, end, info, features);
245 }
246
247 /*
248 * parse entire mds reply
249 */
250 static int parse_reply_info(struct ceph_msg *msg,
251 struct ceph_mds_reply_info_parsed *info,
252 int features)
253 {
254 void *p, *end;
255 u32 len;
256 int err;
257
258 info->head = msg->front.iov_base;
259 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
260 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
261
262 /* trace */
263 ceph_decode_32_safe(&p, end, len, bad);
264 if (len > 0) {
265 err = parse_reply_info_trace(&p, p+len, info, features);
266 if (err < 0)
267 goto out_bad;
268 }
269
270 /* extra */
271 ceph_decode_32_safe(&p, end, len, bad);
272 if (len > 0) {
273 err = parse_reply_info_extra(&p, p+len, info, features);
274 if (err < 0)
275 goto out_bad;
276 }
277
278 /* snap blob */
279 ceph_decode_32_safe(&p, end, len, bad);
280 info->snapblob_len = len;
281 info->snapblob = p;
282 p += len;
283
284 if (p != end)
285 goto bad;
286 return 0;
287
288 bad:
289 err = -EIO;
290 out_bad:
291 pr_err("mds parse_reply err %d\n", err);
292 return err;
293 }
294
295 static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
296 {
297 kfree(info->dir_in);
298 }
299
300
301 /*
302 * sessions
303 */
304 static const char *session_state_name(int s)
305 {
306 switch (s) {
307 case CEPH_MDS_SESSION_NEW: return "new";
308 case CEPH_MDS_SESSION_OPENING: return "opening";
309 case CEPH_MDS_SESSION_OPEN: return "open";
310 case CEPH_MDS_SESSION_HUNG: return "hung";
311 case CEPH_MDS_SESSION_CLOSING: return "closing";
312 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
313 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
314 default: return "???";
315 }
316 }
317
318 static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
319 {
320 if (atomic_inc_not_zero(&s->s_ref)) {
321 dout("mdsc get_session %p %d -> %d\n", s,
322 atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
323 return s;
324 } else {
325 dout("mdsc get_session %p 0 -- FAIL", s);
326 return NULL;
327 }
328 }
329
330 void ceph_put_mds_session(struct ceph_mds_session *s)
331 {
332 dout("mdsc put_session %p %d -> %d\n", s,
333 atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
334 if (atomic_dec_and_test(&s->s_ref)) {
335 if (s->s_authorizer)
336 s->s_mdsc->fsc->client->monc.auth->ops->destroy_authorizer(
337 s->s_mdsc->fsc->client->monc.auth,
338 s->s_authorizer);
339 kfree(s);
340 }
341 }
342
343 /*
344 * called under mdsc->mutex
345 */
346 struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
347 int mds)
348 {
349 struct ceph_mds_session *session;
350
351 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
352 return NULL;
353 session = mdsc->sessions[mds];
354 dout("lookup_mds_session %p %d\n", session,
355 atomic_read(&session->s_ref));
356 get_session(session);
357 return session;
358 }
359
360 static bool __have_session(struct ceph_mds_client *mdsc, int mds)
361 {
362 if (mds >= mdsc->max_sessions)
363 return false;
364 return mdsc->sessions[mds];
365 }
366
367 static int __verify_registered_session(struct ceph_mds_client *mdsc,
368 struct ceph_mds_session *s)
369 {
370 if (s->s_mds >= mdsc->max_sessions ||
371 mdsc->sessions[s->s_mds] != s)
372 return -ENOENT;
373 return 0;
374 }
375
376 /*
377 * create+register a new session for given mds.
378 * called under mdsc->mutex.
379 */
380 static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
381 int mds)
382 {
383 struct ceph_mds_session *s;
384
385 s = kzalloc(sizeof(*s), GFP_NOFS);
386 if (!s)
387 return ERR_PTR(-ENOMEM);
388 s->s_mdsc = mdsc;
389 s->s_mds = mds;
390 s->s_state = CEPH_MDS_SESSION_NEW;
391 s->s_ttl = 0;
392 s->s_seq = 0;
393 mutex_init(&s->s_mutex);
394
395 ceph_con_init(mdsc->fsc->client->msgr, &s->s_con);
396 s->s_con.private = s;
397 s->s_con.ops = &mds_con_ops;
398 s->s_con.peer_name.type = CEPH_ENTITY_TYPE_MDS;
399 s->s_con.peer_name.num = cpu_to_le64(mds);
400
401 spin_lock_init(&s->s_cap_lock);
402 s->s_cap_gen = 0;
403 s->s_cap_ttl = 0;
404 s->s_renew_requested = 0;
405 s->s_renew_seq = 0;
406 INIT_LIST_HEAD(&s->s_caps);
407 s->s_nr_caps = 0;
408 s->s_trim_caps = 0;
409 atomic_set(&s->s_ref, 1);
410 INIT_LIST_HEAD(&s->s_waiting);
411 INIT_LIST_HEAD(&s->s_unsafe);
412 s->s_num_cap_releases = 0;
413 s->s_cap_iterator = NULL;
414 INIT_LIST_HEAD(&s->s_cap_releases);
415 INIT_LIST_HEAD(&s->s_cap_releases_done);
416 INIT_LIST_HEAD(&s->s_cap_flushing);
417 INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
418
419 dout("register_session mds%d\n", mds);
420 if (mds >= mdsc->max_sessions) {
421 int newmax = 1 << get_count_order(mds+1);
422 struct ceph_mds_session **sa;
423
424 dout("register_session realloc to %d\n", newmax);
425 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
426 if (sa == NULL)
427 goto fail_realloc;
428 if (mdsc->sessions) {
429 memcpy(sa, mdsc->sessions,
430 mdsc->max_sessions * sizeof(void *));
431 kfree(mdsc->sessions);
432 }
433 mdsc->sessions = sa;
434 mdsc->max_sessions = newmax;
435 }
436 mdsc->sessions[mds] = s;
437 atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
438
439 ceph_con_open(&s->s_con, ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
440
441 return s;
442
443 fail_realloc:
444 kfree(s);
445 return ERR_PTR(-ENOMEM);
446 }
447
448 /*
449 * called under mdsc->mutex
450 */
451 static void __unregister_session(struct ceph_mds_client *mdsc,
452 struct ceph_mds_session *s)
453 {
454 dout("__unregister_session mds%d %p\n", s->s_mds, s);
455 BUG_ON(mdsc->sessions[s->s_mds] != s);
456 mdsc->sessions[s->s_mds] = NULL;
457 ceph_con_close(&s->s_con);
458 ceph_put_mds_session(s);
459 }
460
461 /*
462 * drop session refs in request.
463 *
464 * should be last request ref, or hold mdsc->mutex
465 */
466 static void put_request_session(struct ceph_mds_request *req)
467 {
468 if (req->r_session) {
469 ceph_put_mds_session(req->r_session);
470 req->r_session = NULL;
471 }
472 }
473
474 void ceph_mdsc_release_request(struct kref *kref)
475 {
476 struct ceph_mds_request *req = container_of(kref,
477 struct ceph_mds_request,
478 r_kref);
479 if (req->r_request)
480 ceph_msg_put(req->r_request);
481 if (req->r_reply) {
482 ceph_msg_put(req->r_reply);
483 destroy_reply_info(&req->r_reply_info);
484 }
485 if (req->r_inode) {
486 ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
487 iput(req->r_inode);
488 }
489 if (req->r_locked_dir)
490 ceph_put_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
491 if (req->r_target_inode)
492 iput(req->r_target_inode);
493 if (req->r_dentry)
494 dput(req->r_dentry);
495 if (req->r_old_dentry) {
496 /*
497 * track (and drop pins for) r_old_dentry_dir
498 * separately, since r_old_dentry's d_parent may have
499 * changed between the dir mutex being dropped and
500 * this request being freed.
501 */
502 ceph_put_cap_refs(ceph_inode(req->r_old_dentry_dir),
503 CEPH_CAP_PIN);
504 dput(req->r_old_dentry);
505 iput(req->r_old_dentry_dir);
506 }
507 kfree(req->r_path1);
508 kfree(req->r_path2);
509 put_request_session(req);
510 ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation);
511 kfree(req);
512 }
513
514 /*
515 * lookup session, bump ref if found.
516 *
517 * called under mdsc->mutex.
518 */
519 static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
520 u64 tid)
521 {
522 struct ceph_mds_request *req;
523 struct rb_node *n = mdsc->request_tree.rb_node;
524
525 while (n) {
526 req = rb_entry(n, struct ceph_mds_request, r_node);
527 if (tid < req->r_tid)
528 n = n->rb_left;
529 else if (tid > req->r_tid)
530 n = n->rb_right;
531 else {
532 ceph_mdsc_get_request(req);
533 return req;
534 }
535 }
536 return NULL;
537 }
538
539 static void __insert_request(struct ceph_mds_client *mdsc,
540 struct ceph_mds_request *new)
541 {
542 struct rb_node **p = &mdsc->request_tree.rb_node;
543 struct rb_node *parent = NULL;
544 struct ceph_mds_request *req = NULL;
545
546 while (*p) {
547 parent = *p;
548 req = rb_entry(parent, struct ceph_mds_request, r_node);
549 if (new->r_tid < req->r_tid)
550 p = &(*p)->rb_left;
551 else if (new->r_tid > req->r_tid)
552 p = &(*p)->rb_right;
553 else
554 BUG();
555 }
556
557 rb_link_node(&new->r_node, parent, p);
558 rb_insert_color(&new->r_node, &mdsc->request_tree);
559 }
560
561 /*
562 * Register an in-flight request, and assign a tid. Link to directory
563 * are modifying (if any).
564 *
565 * Called under mdsc->mutex.
566 */
567 static void __register_request(struct ceph_mds_client *mdsc,
568 struct ceph_mds_request *req,
569 struct inode *dir)
570 {
571 req->r_tid = ++mdsc->last_tid;
572 if (req->r_num_caps)
573 ceph_reserve_caps(mdsc, &req->r_caps_reservation,
574 req->r_num_caps);
575 dout("__register_request %p tid %lld\n", req, req->r_tid);
576 ceph_mdsc_get_request(req);
577 __insert_request(mdsc, req);
578
579 req->r_uid = current_fsuid();
580 req->r_gid = current_fsgid();
581
582 if (dir) {
583 struct ceph_inode_info *ci = ceph_inode(dir);
584
585 ihold(dir);
586 spin_lock(&ci->i_unsafe_lock);
587 req->r_unsafe_dir = dir;
588 list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
589 spin_unlock(&ci->i_unsafe_lock);
590 }
591 }
592
593 static void __unregister_request(struct ceph_mds_client *mdsc,
594 struct ceph_mds_request *req)
595 {
596 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
597 rb_erase(&req->r_node, &mdsc->request_tree);
598 RB_CLEAR_NODE(&req->r_node);
599
600 if (req->r_unsafe_dir) {
601 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
602
603 spin_lock(&ci->i_unsafe_lock);
604 list_del_init(&req->r_unsafe_dir_item);
605 spin_unlock(&ci->i_unsafe_lock);
606
607 iput(req->r_unsafe_dir);
608 req->r_unsafe_dir = NULL;
609 }
610
611 ceph_mdsc_put_request(req);
612 }
613
614 /*
615 * Choose mds to send request to next. If there is a hint set in the
616 * request (e.g., due to a prior forward hint from the mds), use that.
617 * Otherwise, consult frag tree and/or caps to identify the
618 * appropriate mds. If all else fails, choose randomly.
619 *
620 * Called under mdsc->mutex.
621 */
622 struct dentry *get_nonsnap_parent(struct dentry *dentry)
623 {
624 /*
625 * we don't need to worry about protecting the d_parent access
626 * here because we never renaming inside the snapped namespace
627 * except to resplice to another snapdir, and either the old or new
628 * result is a valid result.
629 */
630 while (!IS_ROOT(dentry) && ceph_snap(dentry->d_inode) != CEPH_NOSNAP)
631 dentry = dentry->d_parent;
632 return dentry;
633 }
634
635 static int __choose_mds(struct ceph_mds_client *mdsc,
636 struct ceph_mds_request *req)
637 {
638 struct inode *inode;
639 struct ceph_inode_info *ci;
640 struct ceph_cap *cap;
641 int mode = req->r_direct_mode;
642 int mds = -1;
643 u32 hash = req->r_direct_hash;
644 bool is_hash = req->r_direct_is_hash;
645
646 /*
647 * is there a specific mds we should try? ignore hint if we have
648 * no session and the mds is not up (active or recovering).
649 */
650 if (req->r_resend_mds >= 0 &&
651 (__have_session(mdsc, req->r_resend_mds) ||
652 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
653 dout("choose_mds using resend_mds mds%d\n",
654 req->r_resend_mds);
655 return req->r_resend_mds;
656 }
657
658 if (mode == USE_RANDOM_MDS)
659 goto random;
660
661 inode = NULL;
662 if (req->r_inode) {
663 inode = req->r_inode;
664 } else if (req->r_dentry) {
665 /* ignore race with rename; old or new d_parent is okay */
666 struct dentry *parent = req->r_dentry->d_parent;
667 struct inode *dir = parent->d_inode;
668
669 if (dir->i_sb != mdsc->fsc->sb) {
670 /* not this fs! */
671 inode = req->r_dentry->d_inode;
672 } else if (ceph_snap(dir) != CEPH_NOSNAP) {
673 /* direct snapped/virtual snapdir requests
674 * based on parent dir inode */
675 struct dentry *dn = get_nonsnap_parent(parent);
676 inode = dn->d_inode;
677 dout("__choose_mds using nonsnap parent %p\n", inode);
678 } else if (req->r_dentry->d_inode) {
679 /* dentry target */
680 inode = req->r_dentry->d_inode;
681 } else {
682 /* dir + name */
683 inode = dir;
684 hash = ceph_dentry_hash(dir, req->r_dentry);
685 is_hash = true;
686 }
687 }
688
689 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
690 (int)hash, mode);
691 if (!inode)
692 goto random;
693 ci = ceph_inode(inode);
694
695 if (is_hash && S_ISDIR(inode->i_mode)) {
696 struct ceph_inode_frag frag;
697 int found;
698
699 ceph_choose_frag(ci, hash, &frag, &found);
700 if (found) {
701 if (mode == USE_ANY_MDS && frag.ndist > 0) {
702 u8 r;
703
704 /* choose a random replica */
705 get_random_bytes(&r, 1);
706 r %= frag.ndist;
707 mds = frag.dist[r];
708 dout("choose_mds %p %llx.%llx "
709 "frag %u mds%d (%d/%d)\n",
710 inode, ceph_vinop(inode),
711 frag.frag, mds,
712 (int)r, frag.ndist);
713 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
714 CEPH_MDS_STATE_ACTIVE)
715 return mds;
716 }
717
718 /* since this file/dir wasn't known to be
719 * replicated, then we want to look for the
720 * authoritative mds. */
721 mode = USE_AUTH_MDS;
722 if (frag.mds >= 0) {
723 /* choose auth mds */
724 mds = frag.mds;
725 dout("choose_mds %p %llx.%llx "
726 "frag %u mds%d (auth)\n",
727 inode, ceph_vinop(inode), frag.frag, mds);
728 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
729 CEPH_MDS_STATE_ACTIVE)
730 return mds;
731 }
732 }
733 }
734
735 spin_lock(&inode->i_lock);
736 cap = NULL;
737 if (mode == USE_AUTH_MDS)
738 cap = ci->i_auth_cap;
739 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
740 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
741 if (!cap) {
742 spin_unlock(&inode->i_lock);
743 goto random;
744 }
745 mds = cap->session->s_mds;
746 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
747 inode, ceph_vinop(inode), mds,
748 cap == ci->i_auth_cap ? "auth " : "", cap);
749 spin_unlock(&inode->i_lock);
750 return mds;
751
752 random:
753 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
754 dout("choose_mds chose random mds%d\n", mds);
755 return mds;
756 }
757
758
759 /*
760 * session messages
761 */
762 static struct ceph_msg *create_session_msg(u32 op, u64 seq)
763 {
764 struct ceph_msg *msg;
765 struct ceph_mds_session_head *h;
766
767 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS);
768 if (!msg) {
769 pr_err("create_session_msg ENOMEM creating msg\n");
770 return NULL;
771 }
772 h = msg->front.iov_base;
773 h->op = cpu_to_le32(op);
774 h->seq = cpu_to_le64(seq);
775 return msg;
776 }
777
778 /*
779 * send session open request.
780 *
781 * called under mdsc->mutex
782 */
783 static int __open_session(struct ceph_mds_client *mdsc,
784 struct ceph_mds_session *session)
785 {
786 struct ceph_msg *msg;
787 int mstate;
788 int mds = session->s_mds;
789
790 /* wait for mds to go active? */
791 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
792 dout("open_session to mds%d (%s)\n", mds,
793 ceph_mds_state_name(mstate));
794 session->s_state = CEPH_MDS_SESSION_OPENING;
795 session->s_renew_requested = jiffies;
796
797 /* send connect message */
798 msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
799 if (!msg)
800 return -ENOMEM;
801 ceph_con_send(&session->s_con, msg);
802 return 0;
803 }
804
805 /*
806 * open sessions for any export targets for the given mds
807 *
808 * called under mdsc->mutex
809 */
810 static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
811 struct ceph_mds_session *session)
812 {
813 struct ceph_mds_info *mi;
814 struct ceph_mds_session *ts;
815 int i, mds = session->s_mds;
816 int target;
817
818 if (mds >= mdsc->mdsmap->m_max_mds)
819 return;
820 mi = &mdsc->mdsmap->m_info[mds];
821 dout("open_export_target_sessions for mds%d (%d targets)\n",
822 session->s_mds, mi->num_export_targets);
823
824 for (i = 0; i < mi->num_export_targets; i++) {
825 target = mi->export_targets[i];
826 ts = __ceph_lookup_mds_session(mdsc, target);
827 if (!ts) {
828 ts = register_session(mdsc, target);
829 if (IS_ERR(ts))
830 return;
831 }
832 if (session->s_state == CEPH_MDS_SESSION_NEW ||
833 session->s_state == CEPH_MDS_SESSION_CLOSING)
834 __open_session(mdsc, session);
835 else
836 dout(" mds%d target mds%d %p is %s\n", session->s_mds,
837 i, ts, session_state_name(ts->s_state));
838 ceph_put_mds_session(ts);
839 }
840 }
841
842 void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
843 struct ceph_mds_session *session)
844 {
845 mutex_lock(&mdsc->mutex);
846 __open_export_target_sessions(mdsc, session);
847 mutex_unlock(&mdsc->mutex);
848 }
849
850 /*
851 * session caps
852 */
853
854 /*
855 * Free preallocated cap messages assigned to this session
856 */
857 static void cleanup_cap_releases(struct ceph_mds_session *session)
858 {
859 struct ceph_msg *msg;
860
861 spin_lock(&session->s_cap_lock);
862 while (!list_empty(&session->s_cap_releases)) {
863 msg = list_first_entry(&session->s_cap_releases,
864 struct ceph_msg, list_head);
865 list_del_init(&msg->list_head);
866 ceph_msg_put(msg);
867 }
868 while (!list_empty(&session->s_cap_releases_done)) {
869 msg = list_first_entry(&session->s_cap_releases_done,
870 struct ceph_msg, list_head);
871 list_del_init(&msg->list_head);
872 ceph_msg_put(msg);
873 }
874 spin_unlock(&session->s_cap_lock);
875 }
876
877 /*
878 * Helper to safely iterate over all caps associated with a session, with
879 * special care taken to handle a racing __ceph_remove_cap().
880 *
881 * Caller must hold session s_mutex.
882 */
883 static int iterate_session_caps(struct ceph_mds_session *session,
884 int (*cb)(struct inode *, struct ceph_cap *,
885 void *), void *arg)
886 {
887 struct list_head *p;
888 struct ceph_cap *cap;
889 struct inode *inode, *last_inode = NULL;
890 struct ceph_cap *old_cap = NULL;
891 int ret;
892
893 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
894 spin_lock(&session->s_cap_lock);
895 p = session->s_caps.next;
896 while (p != &session->s_caps) {
897 cap = list_entry(p, struct ceph_cap, session_caps);
898 inode = igrab(&cap->ci->vfs_inode);
899 if (!inode) {
900 p = p->next;
901 continue;
902 }
903 session->s_cap_iterator = cap;
904 spin_unlock(&session->s_cap_lock);
905
906 if (last_inode) {
907 iput(last_inode);
908 last_inode = NULL;
909 }
910 if (old_cap) {
911 ceph_put_cap(session->s_mdsc, old_cap);
912 old_cap = NULL;
913 }
914
915 ret = cb(inode, cap, arg);
916 last_inode = inode;
917
918 spin_lock(&session->s_cap_lock);
919 p = p->next;
920 if (cap->ci == NULL) {
921 dout("iterate_session_caps finishing cap %p removal\n",
922 cap);
923 BUG_ON(cap->session != session);
924 list_del_init(&cap->session_caps);
925 session->s_nr_caps--;
926 cap->session = NULL;
927 old_cap = cap; /* put_cap it w/o locks held */
928 }
929 if (ret < 0)
930 goto out;
931 }
932 ret = 0;
933 out:
934 session->s_cap_iterator = NULL;
935 spin_unlock(&session->s_cap_lock);
936
937 if (last_inode)
938 iput(last_inode);
939 if (old_cap)
940 ceph_put_cap(session->s_mdsc, old_cap);
941
942 return ret;
943 }
944
945 static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
946 void *arg)
947 {
948 struct ceph_inode_info *ci = ceph_inode(inode);
949 int drop = 0;
950
951 dout("removing cap %p, ci is %p, inode is %p\n",
952 cap, ci, &ci->vfs_inode);
953 spin_lock(&inode->i_lock);
954 __ceph_remove_cap(cap);
955 if (!__ceph_is_any_real_caps(ci)) {
956 struct ceph_mds_client *mdsc =
957 ceph_sb_to_client(inode->i_sb)->mdsc;
958
959 spin_lock(&mdsc->cap_dirty_lock);
960 if (!list_empty(&ci->i_dirty_item)) {
961 pr_info(" dropping dirty %s state for %p %lld\n",
962 ceph_cap_string(ci->i_dirty_caps),
963 inode, ceph_ino(inode));
964 ci->i_dirty_caps = 0;
965 list_del_init(&ci->i_dirty_item);
966 drop = 1;
967 }
968 if (!list_empty(&ci->i_flushing_item)) {
969 pr_info(" dropping dirty+flushing %s state for %p %lld\n",
970 ceph_cap_string(ci->i_flushing_caps),
971 inode, ceph_ino(inode));
972 ci->i_flushing_caps = 0;
973 list_del_init(&ci->i_flushing_item);
974 mdsc->num_cap_flushing--;
975 drop = 1;
976 }
977 if (drop && ci->i_wrbuffer_ref) {
978 pr_info(" dropping dirty data for %p %lld\n",
979 inode, ceph_ino(inode));
980 ci->i_wrbuffer_ref = 0;
981 ci->i_wrbuffer_ref_head = 0;
982 drop++;
983 }
984 spin_unlock(&mdsc->cap_dirty_lock);
985 }
986 spin_unlock(&inode->i_lock);
987 while (drop--)
988 iput(inode);
989 return 0;
990 }
991
992 /*
993 * caller must hold session s_mutex
994 */
995 static void remove_session_caps(struct ceph_mds_session *session)
996 {
997 dout("remove_session_caps on %p\n", session);
998 iterate_session_caps(session, remove_session_caps_cb, NULL);
999 BUG_ON(session->s_nr_caps > 0);
1000 BUG_ON(!list_empty(&session->s_cap_flushing));
1001 cleanup_cap_releases(session);
1002 }
1003
1004 /*
1005 * wake up any threads waiting on this session's caps. if the cap is
1006 * old (didn't get renewed on the client reconnect), remove it now.
1007 *
1008 * caller must hold s_mutex.
1009 */
1010 static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
1011 void *arg)
1012 {
1013 struct ceph_inode_info *ci = ceph_inode(inode);
1014
1015 wake_up_all(&ci->i_cap_wq);
1016 if (arg) {
1017 spin_lock(&inode->i_lock);
1018 ci->i_wanted_max_size = 0;
1019 ci->i_requested_max_size = 0;
1020 spin_unlock(&inode->i_lock);
1021 }
1022 return 0;
1023 }
1024
1025 static void wake_up_session_caps(struct ceph_mds_session *session,
1026 int reconnect)
1027 {
1028 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
1029 iterate_session_caps(session, wake_up_session_cb,
1030 (void *)(unsigned long)reconnect);
1031 }
1032
1033 /*
1034 * Send periodic message to MDS renewing all currently held caps. The
1035 * ack will reset the expiration for all caps from this session.
1036 *
1037 * caller holds s_mutex
1038 */
1039 static int send_renew_caps(struct ceph_mds_client *mdsc,
1040 struct ceph_mds_session *session)
1041 {
1042 struct ceph_msg *msg;
1043 int state;
1044
1045 if (time_after_eq(jiffies, session->s_cap_ttl) &&
1046 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
1047 pr_info("mds%d caps stale\n", session->s_mds);
1048 session->s_renew_requested = jiffies;
1049
1050 /* do not try to renew caps until a recovering mds has reconnected
1051 * with its clients. */
1052 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
1053 if (state < CEPH_MDS_STATE_RECONNECT) {
1054 dout("send_renew_caps ignoring mds%d (%s)\n",
1055 session->s_mds, ceph_mds_state_name(state));
1056 return 0;
1057 }
1058
1059 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
1060 ceph_mds_state_name(state));
1061 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
1062 ++session->s_renew_seq);
1063 if (!msg)
1064 return -ENOMEM;
1065 ceph_con_send(&session->s_con, msg);
1066 return 0;
1067 }
1068
1069 /*
1070 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
1071 *
1072 * Called under session->s_mutex
1073 */
1074 static void renewed_caps(struct ceph_mds_client *mdsc,
1075 struct ceph_mds_session *session, int is_renew)
1076 {
1077 int was_stale;
1078 int wake = 0;
1079
1080 spin_lock(&session->s_cap_lock);
1081 was_stale = is_renew && (session->s_cap_ttl == 0 ||
1082 time_after_eq(jiffies, session->s_cap_ttl));
1083
1084 session->s_cap_ttl = session->s_renew_requested +
1085 mdsc->mdsmap->m_session_timeout*HZ;
1086
1087 if (was_stale) {
1088 if (time_before(jiffies, session->s_cap_ttl)) {
1089 pr_info("mds%d caps renewed\n", session->s_mds);
1090 wake = 1;
1091 } else {
1092 pr_info("mds%d caps still stale\n", session->s_mds);
1093 }
1094 }
1095 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
1096 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
1097 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
1098 spin_unlock(&session->s_cap_lock);
1099
1100 if (wake)
1101 wake_up_session_caps(session, 0);
1102 }
1103
1104 /*
1105 * send a session close request
1106 */
1107 static int request_close_session(struct ceph_mds_client *mdsc,
1108 struct ceph_mds_session *session)
1109 {
1110 struct ceph_msg *msg;
1111
1112 dout("request_close_session mds%d state %s seq %lld\n",
1113 session->s_mds, session_state_name(session->s_state),
1114 session->s_seq);
1115 msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
1116 if (!msg)
1117 return -ENOMEM;
1118 ceph_con_send(&session->s_con, msg);
1119 return 0;
1120 }
1121
1122 /*
1123 * Called with s_mutex held.
1124 */
1125 static int __close_session(struct ceph_mds_client *mdsc,
1126 struct ceph_mds_session *session)
1127 {
1128 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
1129 return 0;
1130 session->s_state = CEPH_MDS_SESSION_CLOSING;
1131 return request_close_session(mdsc, session);
1132 }
1133
1134 /*
1135 * Trim old(er) caps.
1136 *
1137 * Because we can't cache an inode without one or more caps, we do
1138 * this indirectly: if a cap is unused, we prune its aliases, at which
1139 * point the inode will hopefully get dropped to.
1140 *
1141 * Yes, this is a bit sloppy. Our only real goal here is to respond to
1142 * memory pressure from the MDS, though, so it needn't be perfect.
1143 */
1144 static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
1145 {
1146 struct ceph_mds_session *session = arg;
1147 struct ceph_inode_info *ci = ceph_inode(inode);
1148 int used, oissued, mine;
1149
1150 if (session->s_trim_caps <= 0)
1151 return -1;
1152
1153 spin_lock(&inode->i_lock);
1154 mine = cap->issued | cap->implemented;
1155 used = __ceph_caps_used(ci);
1156 oissued = __ceph_caps_issued_other(ci, cap);
1157
1158 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s\n",
1159 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
1160 ceph_cap_string(used));
1161 if (ci->i_dirty_caps)
1162 goto out; /* dirty caps */
1163 if ((used & ~oissued) & mine)
1164 goto out; /* we need these caps */
1165
1166 session->s_trim_caps--;
1167 if (oissued) {
1168 /* we aren't the only cap.. just remove us */
1169 __ceph_remove_cap(cap);
1170 } else {
1171 /* try to drop referring dentries */
1172 spin_unlock(&inode->i_lock);
1173 d_prune_aliases(inode);
1174 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
1175 inode, cap, atomic_read(&inode->i_count));
1176 return 0;
1177 }
1178
1179 out:
1180 spin_unlock(&inode->i_lock);
1181 return 0;
1182 }
1183
1184 /*
1185 * Trim session cap count down to some max number.
1186 */
1187 static int trim_caps(struct ceph_mds_client *mdsc,
1188 struct ceph_mds_session *session,
1189 int max_caps)
1190 {
1191 int trim_caps = session->s_nr_caps - max_caps;
1192
1193 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1194 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1195 if (trim_caps > 0) {
1196 session->s_trim_caps = trim_caps;
1197 iterate_session_caps(session, trim_caps_cb, session);
1198 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1199 session->s_mds, session->s_nr_caps, max_caps,
1200 trim_caps - session->s_trim_caps);
1201 session->s_trim_caps = 0;
1202 }
1203 return 0;
1204 }
1205
1206 /*
1207 * Allocate cap_release messages. If there is a partially full message
1208 * in the queue, try to allocate enough to cover it's remainder, so that
1209 * we can send it immediately.
1210 *
1211 * Called under s_mutex.
1212 */
1213 int ceph_add_cap_releases(struct ceph_mds_client *mdsc,
1214 struct ceph_mds_session *session)
1215 {
1216 struct ceph_msg *msg, *partial = NULL;
1217 struct ceph_mds_cap_release *head;
1218 int err = -ENOMEM;
1219 int extra = mdsc->fsc->mount_options->cap_release_safety;
1220 int num;
1221
1222 dout("add_cap_releases %p mds%d extra %d\n", session, session->s_mds,
1223 extra);
1224
1225 spin_lock(&session->s_cap_lock);
1226
1227 if (!list_empty(&session->s_cap_releases)) {
1228 msg = list_first_entry(&session->s_cap_releases,
1229 struct ceph_msg,
1230 list_head);
1231 head = msg->front.iov_base;
1232 num = le32_to_cpu(head->num);
1233 if (num) {
1234 dout(" partial %p with (%d/%d)\n", msg, num,
1235 (int)CEPH_CAPS_PER_RELEASE);
1236 extra += CEPH_CAPS_PER_RELEASE - num;
1237 partial = msg;
1238 }
1239 }
1240 while (session->s_num_cap_releases < session->s_nr_caps + extra) {
1241 spin_unlock(&session->s_cap_lock);
1242 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
1243 GFP_NOFS);
1244 if (!msg)
1245 goto out_unlocked;
1246 dout("add_cap_releases %p msg %p now %d\n", session, msg,
1247 (int)msg->front.iov_len);
1248 head = msg->front.iov_base;
1249 head->num = cpu_to_le32(0);
1250 msg->front.iov_len = sizeof(*head);
1251 spin_lock(&session->s_cap_lock);
1252 list_add(&msg->list_head, &session->s_cap_releases);
1253 session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
1254 }
1255
1256 if (partial) {
1257 head = partial->front.iov_base;
1258 num = le32_to_cpu(head->num);
1259 dout(" queueing partial %p with %d/%d\n", partial, num,
1260 (int)CEPH_CAPS_PER_RELEASE);
1261 list_move_tail(&partial->list_head,
1262 &session->s_cap_releases_done);
1263 session->s_num_cap_releases -= CEPH_CAPS_PER_RELEASE - num;
1264 }
1265 err = 0;
1266 spin_unlock(&session->s_cap_lock);
1267 out_unlocked:
1268 return err;
1269 }
1270
1271 /*
1272 * flush all dirty inode data to disk.
1273 *
1274 * returns true if we've flushed through want_flush_seq
1275 */
1276 static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
1277 {
1278 int mds, ret = 1;
1279
1280 dout("check_cap_flush want %lld\n", want_flush_seq);
1281 mutex_lock(&mdsc->mutex);
1282 for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
1283 struct ceph_mds_session *session = mdsc->sessions[mds];
1284
1285 if (!session)
1286 continue;
1287 get_session(session);
1288 mutex_unlock(&mdsc->mutex);
1289
1290 mutex_lock(&session->s_mutex);
1291 if (!list_empty(&session->s_cap_flushing)) {
1292 struct ceph_inode_info *ci =
1293 list_entry(session->s_cap_flushing.next,
1294 struct ceph_inode_info,
1295 i_flushing_item);
1296 struct inode *inode = &ci->vfs_inode;
1297
1298 spin_lock(&inode->i_lock);
1299 if (ci->i_cap_flush_seq <= want_flush_seq) {
1300 dout("check_cap_flush still flushing %p "
1301 "seq %lld <= %lld to mds%d\n", inode,
1302 ci->i_cap_flush_seq, want_flush_seq,
1303 session->s_mds);
1304 ret = 0;
1305 }
1306 spin_unlock(&inode->i_lock);
1307 }
1308 mutex_unlock(&session->s_mutex);
1309 ceph_put_mds_session(session);
1310
1311 if (!ret)
1312 return ret;
1313 mutex_lock(&mdsc->mutex);
1314 }
1315
1316 mutex_unlock(&mdsc->mutex);
1317 dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
1318 return ret;
1319 }
1320
1321 /*
1322 * called under s_mutex
1323 */
1324 void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
1325 struct ceph_mds_session *session)
1326 {
1327 struct ceph_msg *msg;
1328
1329 dout("send_cap_releases mds%d\n", session->s_mds);
1330 spin_lock(&session->s_cap_lock);
1331 while (!list_empty(&session->s_cap_releases_done)) {
1332 msg = list_first_entry(&session->s_cap_releases_done,
1333 struct ceph_msg, list_head);
1334 list_del_init(&msg->list_head);
1335 spin_unlock(&session->s_cap_lock);
1336 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1337 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1338 ceph_con_send(&session->s_con, msg);
1339 spin_lock(&session->s_cap_lock);
1340 }
1341 spin_unlock(&session->s_cap_lock);
1342 }
1343
1344 static void discard_cap_releases(struct ceph_mds_client *mdsc,
1345 struct ceph_mds_session *session)
1346 {
1347 struct ceph_msg *msg;
1348 struct ceph_mds_cap_release *head;
1349 unsigned num;
1350
1351 dout("discard_cap_releases mds%d\n", session->s_mds);
1352 spin_lock(&session->s_cap_lock);
1353
1354 /* zero out the in-progress message */
1355 msg = list_first_entry(&session->s_cap_releases,
1356 struct ceph_msg, list_head);
1357 head = msg->front.iov_base;
1358 num = le32_to_cpu(head->num);
1359 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, num);
1360 head->num = cpu_to_le32(0);
1361 session->s_num_cap_releases += num;
1362
1363 /* requeue completed messages */
1364 while (!list_empty(&session->s_cap_releases_done)) {
1365 msg = list_first_entry(&session->s_cap_releases_done,
1366 struct ceph_msg, list_head);
1367 list_del_init(&msg->list_head);
1368
1369 head = msg->front.iov_base;
1370 num = le32_to_cpu(head->num);
1371 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg,
1372 num);
1373 session->s_num_cap_releases += num;
1374 head->num = cpu_to_le32(0);
1375 msg->front.iov_len = sizeof(*head);
1376 list_add(&msg->list_head, &session->s_cap_releases);
1377 }
1378
1379 spin_unlock(&session->s_cap_lock);
1380 }
1381
1382 /*
1383 * requests
1384 */
1385
1386 /*
1387 * Create an mds request.
1388 */
1389 struct ceph_mds_request *
1390 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1391 {
1392 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1393
1394 if (!req)
1395 return ERR_PTR(-ENOMEM);
1396
1397 mutex_init(&req->r_fill_mutex);
1398 req->r_mdsc = mdsc;
1399 req->r_started = jiffies;
1400 req->r_resend_mds = -1;
1401 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1402 req->r_fmode = -1;
1403 kref_init(&req->r_kref);
1404 INIT_LIST_HEAD(&req->r_wait);
1405 init_completion(&req->r_completion);
1406 init_completion(&req->r_safe_completion);
1407 INIT_LIST_HEAD(&req->r_unsafe_item);
1408
1409 req->r_op = op;
1410 req->r_direct_mode = mode;
1411 return req;
1412 }
1413
1414 /*
1415 * return oldest (lowest) request, tid in request tree, 0 if none.
1416 *
1417 * called under mdsc->mutex.
1418 */
1419 static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1420 {
1421 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1422 return NULL;
1423 return rb_entry(rb_first(&mdsc->request_tree),
1424 struct ceph_mds_request, r_node);
1425 }
1426
1427 static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1428 {
1429 struct ceph_mds_request *req = __get_oldest_req(mdsc);
1430
1431 if (req)
1432 return req->r_tid;
1433 return 0;
1434 }
1435
1436 /*
1437 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1438 * on build_path_from_dentry in fs/cifs/dir.c.
1439 *
1440 * If @stop_on_nosnap, generate path relative to the first non-snapped
1441 * inode.
1442 *
1443 * Encode hidden .snap dirs as a double /, i.e.
1444 * foo/.snap/bar -> foo//bar
1445 */
1446 char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1447 int stop_on_nosnap)
1448 {
1449 struct dentry *temp;
1450 char *path;
1451 int len, pos;
1452 unsigned seq;
1453
1454 if (dentry == NULL)
1455 return ERR_PTR(-EINVAL);
1456
1457 retry:
1458 len = 0;
1459 seq = read_seqbegin(&rename_lock);
1460 rcu_read_lock();
1461 for (temp = dentry; !IS_ROOT(temp);) {
1462 struct inode *inode = temp->d_inode;
1463 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1464 len++; /* slash only */
1465 else if (stop_on_nosnap && inode &&
1466 ceph_snap(inode) == CEPH_NOSNAP)
1467 break;
1468 else
1469 len += 1 + temp->d_name.len;
1470 temp = temp->d_parent;
1471 if (temp == NULL) {
1472 rcu_read_unlock();
1473 pr_err("build_path corrupt dentry %p\n", dentry);
1474 return ERR_PTR(-EINVAL);
1475 }
1476 }
1477 rcu_read_unlock();
1478 if (len)
1479 len--; /* no leading '/' */
1480
1481 path = kmalloc(len+1, GFP_NOFS);
1482 if (path == NULL)
1483 return ERR_PTR(-ENOMEM);
1484 pos = len;
1485 path[pos] = 0; /* trailing null */
1486 rcu_read_lock();
1487 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1488 struct inode *inode;
1489
1490 spin_lock(&temp->d_lock);
1491 inode = temp->d_inode;
1492 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1493 dout("build_path path+%d: %p SNAPDIR\n",
1494 pos, temp);
1495 } else if (stop_on_nosnap && inode &&
1496 ceph_snap(inode) == CEPH_NOSNAP) {
1497 break;
1498 } else {
1499 pos -= temp->d_name.len;
1500 if (pos < 0) {
1501 spin_unlock(&temp->d_lock);
1502 break;
1503 }
1504 strncpy(path + pos, temp->d_name.name,
1505 temp->d_name.len);
1506 }
1507 spin_unlock(&temp->d_lock);
1508 if (pos)
1509 path[--pos] = '/';
1510 temp = temp->d_parent;
1511 if (temp == NULL) {
1512 rcu_read_unlock();
1513 pr_err("build_path corrupt dentry\n");
1514 kfree(path);
1515 return ERR_PTR(-EINVAL);
1516 }
1517 }
1518 rcu_read_unlock();
1519 if (pos != 0 || read_seqretry(&rename_lock, seq)) {
1520 pr_err("build_path did not end path lookup where "
1521 "expected, namelen is %d, pos is %d\n", len, pos);
1522 /* presumably this is only possible if racing with a
1523 rename of one of the parent directories (we can not
1524 lock the dentries above us to prevent this, but
1525 retrying should be harmless) */
1526 kfree(path);
1527 goto retry;
1528 }
1529
1530 *base = ceph_ino(temp->d_inode);
1531 *plen = len;
1532 dout("build_path on %p %d built %llx '%.*s'\n",
1533 dentry, dentry->d_count, *base, len, path);
1534 return path;
1535 }
1536
1537 static int build_dentry_path(struct dentry *dentry,
1538 const char **ppath, int *ppathlen, u64 *pino,
1539 int *pfreepath)
1540 {
1541 char *path;
1542
1543 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1544 *pino = ceph_ino(dentry->d_parent->d_inode);
1545 *ppath = dentry->d_name.name;
1546 *ppathlen = dentry->d_name.len;
1547 return 0;
1548 }
1549 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1550 if (IS_ERR(path))
1551 return PTR_ERR(path);
1552 *ppath = path;
1553 *pfreepath = 1;
1554 return 0;
1555 }
1556
1557 static int build_inode_path(struct inode *inode,
1558 const char **ppath, int *ppathlen, u64 *pino,
1559 int *pfreepath)
1560 {
1561 struct dentry *dentry;
1562 char *path;
1563
1564 if (ceph_snap(inode) == CEPH_NOSNAP) {
1565 *pino = ceph_ino(inode);
1566 *ppathlen = 0;
1567 return 0;
1568 }
1569 dentry = d_find_alias(inode);
1570 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1571 dput(dentry);
1572 if (IS_ERR(path))
1573 return PTR_ERR(path);
1574 *ppath = path;
1575 *pfreepath = 1;
1576 return 0;
1577 }
1578
1579 /*
1580 * request arguments may be specified via an inode *, a dentry *, or
1581 * an explicit ino+path.
1582 */
1583 static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1584 const char *rpath, u64 rino,
1585 const char **ppath, int *pathlen,
1586 u64 *ino, int *freepath)
1587 {
1588 int r = 0;
1589
1590 if (rinode) {
1591 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1592 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1593 ceph_snap(rinode));
1594 } else if (rdentry) {
1595 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1596 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1597 *ppath);
1598 } else if (rpath || rino) {
1599 *ino = rino;
1600 *ppath = rpath;
1601 *pathlen = strlen(rpath);
1602 dout(" path %.*s\n", *pathlen, rpath);
1603 }
1604
1605 return r;
1606 }
1607
1608 /*
1609 * called under mdsc->mutex
1610 */
1611 static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1612 struct ceph_mds_request *req,
1613 int mds)
1614 {
1615 struct ceph_msg *msg;
1616 struct ceph_mds_request_head *head;
1617 const char *path1 = NULL;
1618 const char *path2 = NULL;
1619 u64 ino1 = 0, ino2 = 0;
1620 int pathlen1 = 0, pathlen2 = 0;
1621 int freepath1 = 0, freepath2 = 0;
1622 int len;
1623 u16 releases;
1624 void *p, *end;
1625 int ret;
1626
1627 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1628 req->r_path1, req->r_ino1.ino,
1629 &path1, &pathlen1, &ino1, &freepath1);
1630 if (ret < 0) {
1631 msg = ERR_PTR(ret);
1632 goto out;
1633 }
1634
1635 ret = set_request_path_attr(NULL, req->r_old_dentry,
1636 req->r_path2, req->r_ino2.ino,
1637 &path2, &pathlen2, &ino2, &freepath2);
1638 if (ret < 0) {
1639 msg = ERR_PTR(ret);
1640 goto out_free1;
1641 }
1642
1643 len = sizeof(*head) +
1644 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
1645
1646 /* calculate (max) length for cap releases */
1647 len += sizeof(struct ceph_mds_request_release) *
1648 (!!req->r_inode_drop + !!req->r_dentry_drop +
1649 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1650 if (req->r_dentry_drop)
1651 len += req->r_dentry->d_name.len;
1652 if (req->r_old_dentry_drop)
1653 len += req->r_old_dentry->d_name.len;
1654
1655 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS);
1656 if (!msg) {
1657 msg = ERR_PTR(-ENOMEM);
1658 goto out_free2;
1659 }
1660
1661 msg->hdr.tid = cpu_to_le64(req->r_tid);
1662
1663 head = msg->front.iov_base;
1664 p = msg->front.iov_base + sizeof(*head);
1665 end = msg->front.iov_base + msg->front.iov_len;
1666
1667 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1668 head->op = cpu_to_le32(req->r_op);
1669 head->caller_uid = cpu_to_le32(req->r_uid);
1670 head->caller_gid = cpu_to_le32(req->r_gid);
1671 head->args = req->r_args;
1672
1673 ceph_encode_filepath(&p, end, ino1, path1);
1674 ceph_encode_filepath(&p, end, ino2, path2);
1675
1676 /* make note of release offset, in case we need to replay */
1677 req->r_request_release_offset = p - msg->front.iov_base;
1678
1679 /* cap releases */
1680 releases = 0;
1681 if (req->r_inode_drop)
1682 releases += ceph_encode_inode_release(&p,
1683 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1684 mds, req->r_inode_drop, req->r_inode_unless, 0);
1685 if (req->r_dentry_drop)
1686 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1687 mds, req->r_dentry_drop, req->r_dentry_unless);
1688 if (req->r_old_dentry_drop)
1689 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1690 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1691 if (req->r_old_inode_drop)
1692 releases += ceph_encode_inode_release(&p,
1693 req->r_old_dentry->d_inode,
1694 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1695 head->num_releases = cpu_to_le16(releases);
1696
1697 BUG_ON(p > end);
1698 msg->front.iov_len = p - msg->front.iov_base;
1699 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1700
1701 msg->pages = req->r_pages;
1702 msg->nr_pages = req->r_num_pages;
1703 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1704 msg->hdr.data_off = cpu_to_le16(0);
1705
1706 out_free2:
1707 if (freepath2)
1708 kfree((char *)path2);
1709 out_free1:
1710 if (freepath1)
1711 kfree((char *)path1);
1712 out:
1713 return msg;
1714 }
1715
1716 /*
1717 * called under mdsc->mutex if error, under no mutex if
1718 * success.
1719 */
1720 static void complete_request(struct ceph_mds_client *mdsc,
1721 struct ceph_mds_request *req)
1722 {
1723 if (req->r_callback)
1724 req->r_callback(mdsc, req);
1725 else
1726 complete_all(&req->r_completion);
1727 }
1728
1729 /*
1730 * called under mdsc->mutex
1731 */
1732 static int __prepare_send_request(struct ceph_mds_client *mdsc,
1733 struct ceph_mds_request *req,
1734 int mds)
1735 {
1736 struct ceph_mds_request_head *rhead;
1737 struct ceph_msg *msg;
1738 int flags = 0;
1739
1740 req->r_attempts++;
1741 if (req->r_inode) {
1742 struct ceph_cap *cap =
1743 ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
1744
1745 if (cap)
1746 req->r_sent_on_mseq = cap->mseq;
1747 else
1748 req->r_sent_on_mseq = -1;
1749 }
1750 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1751 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1752
1753 if (req->r_got_unsafe) {
1754 /*
1755 * Replay. Do not regenerate message (and rebuild
1756 * paths, etc.); just use the original message.
1757 * Rebuilding paths will break for renames because
1758 * d_move mangles the src name.
1759 */
1760 msg = req->r_request;
1761 rhead = msg->front.iov_base;
1762
1763 flags = le32_to_cpu(rhead->flags);
1764 flags |= CEPH_MDS_FLAG_REPLAY;
1765 rhead->flags = cpu_to_le32(flags);
1766
1767 if (req->r_target_inode)
1768 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1769
1770 rhead->num_retry = req->r_attempts - 1;
1771
1772 /* remove cap/dentry releases from message */
1773 rhead->num_releases = 0;
1774 msg->hdr.front_len = cpu_to_le32(req->r_request_release_offset);
1775 msg->front.iov_len = req->r_request_release_offset;
1776 return 0;
1777 }
1778
1779 if (req->r_request) {
1780 ceph_msg_put(req->r_request);
1781 req->r_request = NULL;
1782 }
1783 msg = create_request_message(mdsc, req, mds);
1784 if (IS_ERR(msg)) {
1785 req->r_err = PTR_ERR(msg);
1786 complete_request(mdsc, req);
1787 return PTR_ERR(msg);
1788 }
1789 req->r_request = msg;
1790
1791 rhead = msg->front.iov_base;
1792 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1793 if (req->r_got_unsafe)
1794 flags |= CEPH_MDS_FLAG_REPLAY;
1795 if (req->r_locked_dir)
1796 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1797 rhead->flags = cpu_to_le32(flags);
1798 rhead->num_fwd = req->r_num_fwd;
1799 rhead->num_retry = req->r_attempts - 1;
1800 rhead->ino = 0;
1801
1802 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1803 return 0;
1804 }
1805
1806 /*
1807 * send request, or put it on the appropriate wait list.
1808 */
1809 static int __do_request(struct ceph_mds_client *mdsc,
1810 struct ceph_mds_request *req)
1811 {
1812 struct ceph_mds_session *session = NULL;
1813 int mds = -1;
1814 int err = -EAGAIN;
1815
1816 if (req->r_err || req->r_got_result)
1817 goto out;
1818
1819 if (req->r_timeout &&
1820 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1821 dout("do_request timed out\n");
1822 err = -EIO;
1823 goto finish;
1824 }
1825
1826 put_request_session(req);
1827
1828 mds = __choose_mds(mdsc, req);
1829 if (mds < 0 ||
1830 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1831 dout("do_request no mds or not active, waiting for map\n");
1832 list_add(&req->r_wait, &mdsc->waiting_for_map);
1833 goto out;
1834 }
1835
1836 /* get, open session */
1837 session = __ceph_lookup_mds_session(mdsc, mds);
1838 if (!session) {
1839 session = register_session(mdsc, mds);
1840 if (IS_ERR(session)) {
1841 err = PTR_ERR(session);
1842 goto finish;
1843 }
1844 }
1845 req->r_session = get_session(session);
1846
1847 dout("do_request mds%d session %p state %s\n", mds, session,
1848 session_state_name(session->s_state));
1849 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
1850 session->s_state != CEPH_MDS_SESSION_HUNG) {
1851 if (session->s_state == CEPH_MDS_SESSION_NEW ||
1852 session->s_state == CEPH_MDS_SESSION_CLOSING)
1853 __open_session(mdsc, session);
1854 list_add(&req->r_wait, &session->s_waiting);
1855 goto out_session;
1856 }
1857
1858 /* send request */
1859 req->r_resend_mds = -1; /* forget any previous mds hint */
1860
1861 if (req->r_request_started == 0) /* note request start time */
1862 req->r_request_started = jiffies;
1863
1864 err = __prepare_send_request(mdsc, req, mds);
1865 if (!err) {
1866 ceph_msg_get(req->r_request);
1867 ceph_con_send(&session->s_con, req->r_request);
1868 }
1869
1870 out_session:
1871 ceph_put_mds_session(session);
1872 out:
1873 return err;
1874
1875 finish:
1876 req->r_err = err;
1877 complete_request(mdsc, req);
1878 goto out;
1879 }
1880
1881 /*
1882 * called under mdsc->mutex
1883 */
1884 static void __wake_requests(struct ceph_mds_client *mdsc,
1885 struct list_head *head)
1886 {
1887 struct ceph_mds_request *req, *nreq;
1888
1889 list_for_each_entry_safe(req, nreq, head, r_wait) {
1890 list_del_init(&req->r_wait);
1891 __do_request(mdsc, req);
1892 }
1893 }
1894
1895 /*
1896 * Wake up threads with requests pending for @mds, so that they can
1897 * resubmit their requests to a possibly different mds.
1898 */
1899 static void kick_requests(struct ceph_mds_client *mdsc, int mds)
1900 {
1901 struct ceph_mds_request *req;
1902 struct rb_node *p;
1903
1904 dout("kick_requests mds%d\n", mds);
1905 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
1906 req = rb_entry(p, struct ceph_mds_request, r_node);
1907 if (req->r_got_unsafe)
1908 continue;
1909 if (req->r_session &&
1910 req->r_session->s_mds == mds) {
1911 dout(" kicking tid %llu\n", req->r_tid);
1912 __do_request(mdsc, req);
1913 }
1914 }
1915 }
1916
1917 void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
1918 struct ceph_mds_request *req)
1919 {
1920 dout("submit_request on %p\n", req);
1921 mutex_lock(&mdsc->mutex);
1922 __register_request(mdsc, req, NULL);
1923 __do_request(mdsc, req);
1924 mutex_unlock(&mdsc->mutex);
1925 }
1926
1927 /*
1928 * Synchrously perform an mds request. Take care of all of the
1929 * session setup, forwarding, retry details.
1930 */
1931 int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
1932 struct inode *dir,
1933 struct ceph_mds_request *req)
1934 {
1935 int err;
1936
1937 dout("do_request on %p\n", req);
1938
1939 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
1940 if (req->r_inode)
1941 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
1942 if (req->r_locked_dir)
1943 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
1944 if (req->r_old_dentry)
1945 ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
1946 CEPH_CAP_PIN);
1947
1948 /* issue */
1949 mutex_lock(&mdsc->mutex);
1950 __register_request(mdsc, req, dir);
1951 __do_request(mdsc, req);
1952
1953 if (req->r_err) {
1954 err = req->r_err;
1955 __unregister_request(mdsc, req);
1956 dout("do_request early error %d\n", err);
1957 goto out;
1958 }
1959
1960 /* wait */
1961 mutex_unlock(&mdsc->mutex);
1962 dout("do_request waiting\n");
1963 if (req->r_timeout) {
1964 err = (long)wait_for_completion_killable_timeout(
1965 &req->r_completion, req->r_timeout);
1966 if (err == 0)
1967 err = -EIO;
1968 } else {
1969 err = wait_for_completion_killable(&req->r_completion);
1970 }
1971 dout("do_request waited, got %d\n", err);
1972 mutex_lock(&mdsc->mutex);
1973
1974 /* only abort if we didn't race with a real reply */
1975 if (req->r_got_result) {
1976 err = le32_to_cpu(req->r_reply_info.head->result);
1977 } else if (err < 0) {
1978 dout("aborted request %lld with %d\n", req->r_tid, err);
1979
1980 /*
1981 * ensure we aren't running concurrently with
1982 * ceph_fill_trace or ceph_readdir_prepopulate, which
1983 * rely on locks (dir mutex) held by our caller.
1984 */
1985 mutex_lock(&req->r_fill_mutex);
1986 req->r_err = err;
1987 req->r_aborted = true;
1988 mutex_unlock(&req->r_fill_mutex);
1989
1990 if (req->r_locked_dir &&
1991 (req->r_op & CEPH_MDS_OP_WRITE))
1992 ceph_invalidate_dir_request(req);
1993 } else {
1994 err = req->r_err;
1995 }
1996
1997 out:
1998 mutex_unlock(&mdsc->mutex);
1999 dout("do_request %p done, result %d\n", req, err);
2000 return err;
2001 }
2002
2003 /*
2004 * Invalidate dir I_COMPLETE, dentry lease state on an aborted MDS
2005 * namespace request.
2006 */
2007 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
2008 {
2009 struct inode *inode = req->r_locked_dir;
2010 struct ceph_inode_info *ci = ceph_inode(inode);
2011
2012 dout("invalidate_dir_request %p (I_COMPLETE, lease(s))\n", inode);
2013 spin_lock(&inode->i_lock);
2014 ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
2015 ci->i_release_count++;
2016 spin_unlock(&inode->i_lock);
2017
2018 if (req->r_dentry)
2019 ceph_invalidate_dentry_lease(req->r_dentry);
2020 if (req->r_old_dentry)
2021 ceph_invalidate_dentry_lease(req->r_old_dentry);
2022 }
2023
2024 /*
2025 * Handle mds reply.
2026 *
2027 * We take the session mutex and parse and process the reply immediately.
2028 * This preserves the logical ordering of replies, capabilities, etc., sent
2029 * by the MDS as they are applied to our local cache.
2030 */
2031 static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
2032 {
2033 struct ceph_mds_client *mdsc = session->s_mdsc;
2034 struct ceph_mds_request *req;
2035 struct ceph_mds_reply_head *head = msg->front.iov_base;
2036 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
2037 u64 tid;
2038 int err, result;
2039 int mds = session->s_mds;
2040
2041 if (msg->front.iov_len < sizeof(*head)) {
2042 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
2043 ceph_msg_dump(msg);
2044 return;
2045 }
2046
2047 /* get request, session */
2048 tid = le64_to_cpu(msg->hdr.tid);
2049 mutex_lock(&mdsc->mutex);
2050 req = __lookup_request(mdsc, tid);
2051 if (!req) {
2052 dout("handle_reply on unknown tid %llu\n", tid);
2053 mutex_unlock(&mdsc->mutex);
2054 return;
2055 }
2056 dout("handle_reply %p\n", req);
2057
2058 /* correct session? */
2059 if (req->r_session != session) {
2060 pr_err("mdsc_handle_reply got %llu on session mds%d"
2061 " not mds%d\n", tid, session->s_mds,
2062 req->r_session ? req->r_session->s_mds : -1);
2063 mutex_unlock(&mdsc->mutex);
2064 goto out;
2065 }
2066
2067 /* dup? */
2068 if ((req->r_got_unsafe && !head->safe) ||
2069 (req->r_got_safe && head->safe)) {
2070 pr_warning("got a dup %s reply on %llu from mds%d\n",
2071 head->safe ? "safe" : "unsafe", tid, mds);
2072 mutex_unlock(&mdsc->mutex);
2073 goto out;
2074 }
2075 if (req->r_got_safe && !head->safe) {
2076 pr_warning("got unsafe after safe on %llu from mds%d\n",
2077 tid, mds);
2078 mutex_unlock(&mdsc->mutex);
2079 goto out;
2080 }
2081
2082 result = le32_to_cpu(head->result);
2083
2084 /*
2085 * Handle an ESTALE
2086 * if we're not talking to the authority, send to them
2087 * if the authority has changed while we weren't looking,
2088 * send to new authority
2089 * Otherwise we just have to return an ESTALE
2090 */
2091 if (result == -ESTALE) {
2092 dout("got ESTALE on request %llu", req->r_tid);
2093 if (!req->r_inode) {
2094 /* do nothing; not an authority problem */
2095 } else if (req->r_direct_mode != USE_AUTH_MDS) {
2096 dout("not using auth, setting for that now");
2097 req->r_direct_mode = USE_AUTH_MDS;
2098 __do_request(mdsc, req);
2099 mutex_unlock(&mdsc->mutex);
2100 goto out;
2101 } else {
2102 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
2103 struct ceph_cap *cap = NULL;
2104
2105 if (req->r_session)
2106 cap = ceph_get_cap_for_mds(ci,
2107 req->r_session->s_mds);
2108
2109 dout("already using auth");
2110 if ((!cap || cap != ci->i_auth_cap) ||
2111 (cap->mseq != req->r_sent_on_mseq)) {
2112 dout("but cap changed, so resending");
2113 __do_request(mdsc, req);
2114 mutex_unlock(&mdsc->mutex);
2115 goto out;
2116 }
2117 }
2118 dout("have to return ESTALE on request %llu", req->r_tid);
2119 }
2120
2121
2122 if (head->safe) {
2123 req->r_got_safe = true;
2124 __unregister_request(mdsc, req);
2125 complete_all(&req->r_safe_completion);
2126
2127 if (req->r_got_unsafe) {
2128 /*
2129 * We already handled the unsafe response, now do the
2130 * cleanup. No need to examine the response; the MDS
2131 * doesn't include any result info in the safe
2132 * response. And even if it did, there is nothing
2133 * useful we could do with a revised return value.
2134 */
2135 dout("got safe reply %llu, mds%d\n", tid, mds);
2136 list_del_init(&req->r_unsafe_item);
2137
2138 /* last unsafe request during umount? */
2139 if (mdsc->stopping && !__get_oldest_req(mdsc))
2140 complete_all(&mdsc->safe_umount_waiters);
2141 mutex_unlock(&mdsc->mutex);
2142 goto out;
2143 }
2144 } else {
2145 req->r_got_unsafe = true;
2146 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
2147 }
2148
2149 dout("handle_reply tid %lld result %d\n", tid, result);
2150 rinfo = &req->r_reply_info;
2151 err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
2152 mutex_unlock(&mdsc->mutex);
2153
2154 mutex_lock(&session->s_mutex);
2155 if (err < 0) {
2156 pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
2157 ceph_msg_dump(msg);
2158 goto out_err;
2159 }
2160
2161 /* snap trace */
2162 if (rinfo->snapblob_len) {
2163 down_write(&mdsc->snap_rwsem);
2164 ceph_update_snap_trace(mdsc, rinfo->snapblob,
2165 rinfo->snapblob + rinfo->snapblob_len,
2166 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
2167 downgrade_write(&mdsc->snap_rwsem);
2168 } else {
2169 down_read(&mdsc->snap_rwsem);
2170 }
2171
2172 /* insert trace into our cache */
2173 mutex_lock(&req->r_fill_mutex);
2174 err = ceph_fill_trace(mdsc->fsc->sb, req, req->r_session);
2175 if (err == 0) {
2176 if (result == 0 && req->r_op != CEPH_MDS_OP_GETFILELOCK &&
2177 rinfo->dir_nr)
2178 ceph_readdir_prepopulate(req, req->r_session);
2179 ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
2180 }
2181 mutex_unlock(&req->r_fill_mutex);
2182
2183 up_read(&mdsc->snap_rwsem);
2184 out_err:
2185 mutex_lock(&mdsc->mutex);
2186 if (!req->r_aborted) {
2187 if (err) {
2188 req->r_err = err;
2189 } else {
2190 req->r_reply = msg;
2191 ceph_msg_get(msg);
2192 req->r_got_result = true;
2193 }
2194 } else {
2195 dout("reply arrived after request %lld was aborted\n", tid);
2196 }
2197 mutex_unlock(&mdsc->mutex);
2198
2199 ceph_add_cap_releases(mdsc, req->r_session);
2200 mutex_unlock(&session->s_mutex);
2201
2202 /* kick calling process */
2203 complete_request(mdsc, req);
2204 out:
2205 ceph_mdsc_put_request(req);
2206 return;
2207 }
2208
2209
2210
2211 /*
2212 * handle mds notification that our request has been forwarded.
2213 */
2214 static void handle_forward(struct ceph_mds_client *mdsc,
2215 struct ceph_mds_session *session,
2216 struct ceph_msg *msg)
2217 {
2218 struct ceph_mds_request *req;
2219 u64 tid = le64_to_cpu(msg->hdr.tid);
2220 u32 next_mds;
2221 u32 fwd_seq;
2222 int err = -EINVAL;
2223 void *p = msg->front.iov_base;
2224 void *end = p + msg->front.iov_len;
2225
2226 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
2227 next_mds = ceph_decode_32(&p);
2228 fwd_seq = ceph_decode_32(&p);
2229
2230 mutex_lock(&mdsc->mutex);
2231 req = __lookup_request(mdsc, tid);
2232 if (!req) {
2233 dout("forward tid %llu to mds%d - req dne\n", tid, next_mds);
2234 goto out; /* dup reply? */
2235 }
2236
2237 if (req->r_aborted) {
2238 dout("forward tid %llu aborted, unregistering\n", tid);
2239 __unregister_request(mdsc, req);
2240 } else if (fwd_seq <= req->r_num_fwd) {
2241 dout("forward tid %llu to mds%d - old seq %d <= %d\n",
2242 tid, next_mds, req->r_num_fwd, fwd_seq);
2243 } else {
2244 /* resend. forward race not possible; mds would drop */
2245 dout("forward tid %llu to mds%d (we resend)\n", tid, next_mds);
2246 BUG_ON(req->r_err);
2247 BUG_ON(req->r_got_result);
2248 req->r_num_fwd = fwd_seq;
2249 req->r_resend_mds = next_mds;
2250 put_request_session(req);
2251 __do_request(mdsc, req);
2252 }
2253 ceph_mdsc_put_request(req);
2254 out:
2255 mutex_unlock(&mdsc->mutex);
2256 return;
2257
2258 bad:
2259 pr_err("mdsc_handle_forward decode error err=%d\n", err);
2260 }
2261
2262 /*
2263 * handle a mds session control message
2264 */
2265 static void handle_session(struct ceph_mds_session *session,
2266 struct ceph_msg *msg)
2267 {
2268 struct ceph_mds_client *mdsc = session->s_mdsc;
2269 u32 op;
2270 u64 seq;
2271 int mds = session->s_mds;
2272 struct ceph_mds_session_head *h = msg->front.iov_base;
2273 int wake = 0;
2274
2275 /* decode */
2276 if (msg->front.iov_len != sizeof(*h))
2277 goto bad;
2278 op = le32_to_cpu(h->op);
2279 seq = le64_to_cpu(h->seq);
2280
2281 mutex_lock(&mdsc->mutex);
2282 if (op == CEPH_SESSION_CLOSE)
2283 __unregister_session(mdsc, session);
2284 /* FIXME: this ttl calculation is generous */
2285 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2286 mutex_unlock(&mdsc->mutex);
2287
2288 mutex_lock(&session->s_mutex);
2289
2290 dout("handle_session mds%d %s %p state %s seq %llu\n",
2291 mds, ceph_session_op_name(op), session,
2292 session_state_name(session->s_state), seq);
2293
2294 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2295 session->s_state = CEPH_MDS_SESSION_OPEN;
2296 pr_info("mds%d came back\n", session->s_mds);
2297 }
2298
2299 switch (op) {
2300 case CEPH_SESSION_OPEN:
2301 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2302 pr_info("mds%d reconnect success\n", session->s_mds);
2303 session->s_state = CEPH_MDS_SESSION_OPEN;
2304 renewed_caps(mdsc, session, 0);
2305 wake = 1;
2306 if (mdsc->stopping)
2307 __close_session(mdsc, session);
2308 break;
2309
2310 case CEPH_SESSION_RENEWCAPS:
2311 if (session->s_renew_seq == seq)
2312 renewed_caps(mdsc, session, 1);
2313 break;
2314
2315 case CEPH_SESSION_CLOSE:
2316 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2317 pr_info("mds%d reconnect denied\n", session->s_mds);
2318 remove_session_caps(session);
2319 wake = 1; /* for good measure */
2320 wake_up_all(&mdsc->session_close_wq);
2321 kick_requests(mdsc, mds);
2322 break;
2323
2324 case CEPH_SESSION_STALE:
2325 pr_info("mds%d caps went stale, renewing\n",
2326 session->s_mds);
2327 spin_lock(&session->s_cap_lock);
2328 session->s_cap_gen++;
2329 session->s_cap_ttl = 0;
2330 spin_unlock(&session->s_cap_lock);
2331 send_renew_caps(mdsc, session);
2332 break;
2333
2334 case CEPH_SESSION_RECALL_STATE:
2335 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2336 break;
2337
2338 default:
2339 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2340 WARN_ON(1);
2341 }
2342
2343 mutex_unlock(&session->s_mutex);
2344 if (wake) {
2345 mutex_lock(&mdsc->mutex);
2346 __wake_requests(mdsc, &session->s_waiting);
2347 mutex_unlock(&mdsc->mutex);
2348 }
2349 return;
2350
2351 bad:
2352 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2353 (int)msg->front.iov_len);
2354 ceph_msg_dump(msg);
2355 return;
2356 }
2357
2358
2359 /*
2360 * called under session->mutex.
2361 */
2362 static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2363 struct ceph_mds_session *session)
2364 {
2365 struct ceph_mds_request *req, *nreq;
2366 int err;
2367
2368 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2369
2370 mutex_lock(&mdsc->mutex);
2371 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2372 err = __prepare_send_request(mdsc, req, session->s_mds);
2373 if (!err) {
2374 ceph_msg_get(req->r_request);
2375 ceph_con_send(&session->s_con, req->r_request);
2376 }
2377 }
2378 mutex_unlock(&mdsc->mutex);
2379 }
2380
2381 /*
2382 * Encode information about a cap for a reconnect with the MDS.
2383 */
2384 static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2385 void *arg)
2386 {
2387 union {
2388 struct ceph_mds_cap_reconnect v2;
2389 struct ceph_mds_cap_reconnect_v1 v1;
2390 } rec;
2391 size_t reclen;
2392 struct ceph_inode_info *ci;
2393 struct ceph_reconnect_state *recon_state = arg;
2394 struct ceph_pagelist *pagelist = recon_state->pagelist;
2395 char *path;
2396 int pathlen, err;
2397 u64 pathbase;
2398 struct dentry *dentry;
2399
2400 ci = cap->ci;
2401
2402 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2403 inode, ceph_vinop(inode), cap, cap->cap_id,
2404 ceph_cap_string(cap->issued));
2405 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2406 if (err)
2407 return err;
2408
2409 dentry = d_find_alias(inode);
2410 if (dentry) {
2411 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2412 if (IS_ERR(path)) {
2413 err = PTR_ERR(path);
2414 goto out_dput;
2415 }
2416 } else {
2417 path = NULL;
2418 pathlen = 0;
2419 }
2420 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2421 if (err)
2422 goto out_free;
2423
2424 spin_lock(&inode->i_lock);
2425 cap->seq = 0; /* reset cap seq */
2426 cap->issue_seq = 0; /* and issue_seq */
2427
2428 if (recon_state->flock) {
2429 rec.v2.cap_id = cpu_to_le64(cap->cap_id);
2430 rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2431 rec.v2.issued = cpu_to_le32(cap->issued);
2432 rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2433 rec.v2.pathbase = cpu_to_le64(pathbase);
2434 rec.v2.flock_len = 0;
2435 reclen = sizeof(rec.v2);
2436 } else {
2437 rec.v1.cap_id = cpu_to_le64(cap->cap_id);
2438 rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2439 rec.v1.issued = cpu_to_le32(cap->issued);
2440 rec.v1.size = cpu_to_le64(inode->i_size);
2441 ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
2442 ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
2443 rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2444 rec.v1.pathbase = cpu_to_le64(pathbase);
2445 reclen = sizeof(rec.v1);
2446 }
2447 spin_unlock(&inode->i_lock);
2448
2449 if (recon_state->flock) {
2450 int num_fcntl_locks, num_flock_locks;
2451 struct ceph_pagelist_cursor trunc_point;
2452
2453 ceph_pagelist_set_cursor(pagelist, &trunc_point);
2454 do {
2455 lock_flocks();
2456 ceph_count_locks(inode, &num_fcntl_locks,
2457 &num_flock_locks);
2458 rec.v2.flock_len = (2*sizeof(u32) +
2459 (num_fcntl_locks+num_flock_locks) *
2460 sizeof(struct ceph_filelock));
2461 unlock_flocks();
2462
2463 /* pre-alloc pagelist */
2464 ceph_pagelist_truncate(pagelist, &trunc_point);
2465 err = ceph_pagelist_append(pagelist, &rec, reclen);
2466 if (!err)
2467 err = ceph_pagelist_reserve(pagelist,
2468 rec.v2.flock_len);
2469
2470 /* encode locks */
2471 if (!err) {
2472 lock_flocks();
2473 err = ceph_encode_locks(inode,
2474 pagelist,
2475 num_fcntl_locks,
2476 num_flock_locks);
2477 unlock_flocks();
2478 }
2479 } while (err == -ENOSPC);
2480 } else {
2481 err = ceph_pagelist_append(pagelist, &rec, reclen);
2482 }
2483
2484 out_free:
2485 kfree(path);
2486 out_dput:
2487 dput(dentry);
2488 return err;
2489 }
2490
2491
2492 /*
2493 * If an MDS fails and recovers, clients need to reconnect in order to
2494 * reestablish shared state. This includes all caps issued through
2495 * this session _and_ the snap_realm hierarchy. Because it's not
2496 * clear which snap realms the mds cares about, we send everything we
2497 * know about.. that ensures we'll then get any new info the
2498 * recovering MDS might have.
2499 *
2500 * This is a relatively heavyweight operation, but it's rare.
2501 *
2502 * called with mdsc->mutex held.
2503 */
2504 static void send_mds_reconnect(struct ceph_mds_client *mdsc,
2505 struct ceph_mds_session *session)
2506 {
2507 struct ceph_msg *reply;
2508 struct rb_node *p;
2509 int mds = session->s_mds;
2510 int err = -ENOMEM;
2511 struct ceph_pagelist *pagelist;
2512 struct ceph_reconnect_state recon_state;
2513
2514 pr_info("mds%d reconnect start\n", mds);
2515
2516 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2517 if (!pagelist)
2518 goto fail_nopagelist;
2519 ceph_pagelist_init(pagelist);
2520
2521 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS);
2522 if (!reply)
2523 goto fail_nomsg;
2524
2525 mutex_lock(&session->s_mutex);
2526 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2527 session->s_seq = 0;
2528
2529 ceph_con_open(&session->s_con,
2530 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2531
2532 /* replay unsafe requests */
2533 replay_unsafe_requests(mdsc, session);
2534
2535 down_read(&mdsc->snap_rwsem);
2536
2537 dout("session %p state %s\n", session,
2538 session_state_name(session->s_state));
2539
2540 /* drop old cap expires; we're about to reestablish that state */
2541 discard_cap_releases(mdsc, session);
2542
2543 /* traverse this session's caps */
2544 err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
2545 if (err)
2546 goto fail;
2547
2548 recon_state.pagelist = pagelist;
2549 recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK;
2550 err = iterate_session_caps(session, encode_caps_cb, &recon_state);
2551 if (err < 0)
2552 goto fail;
2553
2554 /*
2555 * snaprealms. we provide mds with the ino, seq (version), and
2556 * parent for all of our realms. If the mds has any newer info,
2557 * it will tell us.
2558 */
2559 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2560 struct ceph_snap_realm *realm =
2561 rb_entry(p, struct ceph_snap_realm, node);
2562 struct ceph_mds_snaprealm_reconnect sr_rec;
2563
2564 dout(" adding snap realm %llx seq %lld parent %llx\n",
2565 realm->ino, realm->seq, realm->parent_ino);
2566 sr_rec.ino = cpu_to_le64(realm->ino);
2567 sr_rec.seq = cpu_to_le64(realm->seq);
2568 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2569 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2570 if (err)
2571 goto fail;
2572 }
2573
2574 reply->pagelist = pagelist;
2575 if (recon_state.flock)
2576 reply->hdr.version = cpu_to_le16(2);
2577 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2578 reply->nr_pages = calc_pages_for(0, pagelist->length);
2579 ceph_con_send(&session->s_con, reply);
2580
2581 mutex_unlock(&session->s_mutex);
2582
2583 mutex_lock(&mdsc->mutex);
2584 __wake_requests(mdsc, &session->s_waiting);
2585 mutex_unlock(&mdsc->mutex);
2586
2587 up_read(&mdsc->snap_rwsem);
2588 return;
2589
2590 fail:
2591 ceph_msg_put(reply);
2592 up_read(&mdsc->snap_rwsem);
2593 mutex_unlock(&session->s_mutex);
2594 fail_nomsg:
2595 ceph_pagelist_release(pagelist);
2596 kfree(pagelist);
2597 fail_nopagelist:
2598 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
2599 return;
2600 }
2601
2602
2603 /*
2604 * compare old and new mdsmaps, kicking requests
2605 * and closing out old connections as necessary
2606 *
2607 * called under mdsc->mutex.
2608 */
2609 static void check_new_map(struct ceph_mds_client *mdsc,
2610 struct ceph_mdsmap *newmap,
2611 struct ceph_mdsmap *oldmap)
2612 {
2613 int i;
2614 int oldstate, newstate;
2615 struct ceph_mds_session *s;
2616
2617 dout("check_new_map new %u old %u\n",
2618 newmap->m_epoch, oldmap->m_epoch);
2619
2620 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2621 if (mdsc->sessions[i] == NULL)
2622 continue;
2623 s = mdsc->sessions[i];
2624 oldstate = ceph_mdsmap_get_state(oldmap, i);
2625 newstate = ceph_mdsmap_get_state(newmap, i);
2626
2627 dout("check_new_map mds%d state %s%s -> %s%s (session %s)\n",
2628 i, ceph_mds_state_name(oldstate),
2629 ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "",
2630 ceph_mds_state_name(newstate),
2631 ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
2632 session_state_name(s->s_state));
2633
2634 if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
2635 ceph_mdsmap_get_addr(newmap, i),
2636 sizeof(struct ceph_entity_addr))) {
2637 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2638 /* the session never opened, just close it
2639 * out now */
2640 __wake_requests(mdsc, &s->s_waiting);
2641 __unregister_session(mdsc, s);
2642 } else {
2643 /* just close it */
2644 mutex_unlock(&mdsc->mutex);
2645 mutex_lock(&s->s_mutex);
2646 mutex_lock(&mdsc->mutex);
2647 ceph_con_close(&s->s_con);
2648 mutex_unlock(&s->s_mutex);
2649 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2650 }
2651
2652 /* kick any requests waiting on the recovering mds */
2653 kick_requests(mdsc, i);
2654 } else if (oldstate == newstate) {
2655 continue; /* nothing new with this mds */
2656 }
2657
2658 /*
2659 * send reconnect?
2660 */
2661 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2662 newstate >= CEPH_MDS_STATE_RECONNECT) {
2663 mutex_unlock(&mdsc->mutex);
2664 send_mds_reconnect(mdsc, s);
2665 mutex_lock(&mdsc->mutex);
2666 }
2667
2668 /*
2669 * kick request on any mds that has gone active.
2670 */
2671 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2672 newstate >= CEPH_MDS_STATE_ACTIVE) {
2673 if (oldstate != CEPH_MDS_STATE_CREATING &&
2674 oldstate != CEPH_MDS_STATE_STARTING)
2675 pr_info("mds%d recovery completed\n", s->s_mds);
2676 kick_requests(mdsc, i);
2677 ceph_kick_flushing_caps(mdsc, s);
2678 wake_up_session_caps(s, 1);
2679 }
2680 }
2681
2682 for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
2683 s = mdsc->sessions[i];
2684 if (!s)
2685 continue;
2686 if (!ceph_mdsmap_is_laggy(newmap, i))
2687 continue;
2688 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2689 s->s_state == CEPH_MDS_SESSION_HUNG ||
2690 s->s_state == CEPH_MDS_SESSION_CLOSING) {
2691 dout(" connecting to export targets of laggy mds%d\n",
2692 i);
2693 __open_export_target_sessions(mdsc, s);
2694 }
2695 }
2696 }
2697
2698
2699
2700 /*
2701 * leases
2702 */
2703
2704 /*
2705 * caller must hold session s_mutex, dentry->d_lock
2706 */
2707 void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2708 {
2709 struct ceph_dentry_info *di = ceph_dentry(dentry);
2710
2711 ceph_put_mds_session(di->lease_session);
2712 di->lease_session = NULL;
2713 }
2714
2715 static void handle_lease(struct ceph_mds_client *mdsc,
2716 struct ceph_mds_session *session,
2717 struct ceph_msg *msg)
2718 {
2719 struct super_block *sb = mdsc->fsc->sb;
2720 struct inode *inode;
2721 struct dentry *parent, *dentry;
2722 struct ceph_dentry_info *di;
2723 int mds = session->s_mds;
2724 struct ceph_mds_lease *h = msg->front.iov_base;
2725 u32 seq;
2726 struct ceph_vino vino;
2727 struct qstr dname;
2728 int release = 0;
2729
2730 dout("handle_lease from mds%d\n", mds);
2731
2732 /* decode */
2733 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2734 goto bad;
2735 vino.ino = le64_to_cpu(h->ino);
2736 vino.snap = CEPH_NOSNAP;
2737 seq = le32_to_cpu(h->seq);
2738 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2739 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2740 if (dname.len != get_unaligned_le32(h+1))
2741 goto bad;
2742
2743 mutex_lock(&session->s_mutex);
2744 session->s_seq++;
2745
2746 /* lookup inode */
2747 inode = ceph_find_inode(sb, vino);
2748 dout("handle_lease %s, ino %llx %p %.*s\n",
2749 ceph_lease_op_name(h->action), vino.ino, inode,
2750 dname.len, dname.name);
2751 if (inode == NULL) {
2752 dout("handle_lease no inode %llx\n", vino.ino);
2753 goto release;
2754 }
2755
2756 /* dentry */
2757 parent = d_find_alias(inode);
2758 if (!parent) {
2759 dout("no parent dentry on inode %p\n", inode);
2760 WARN_ON(1);
2761 goto release; /* hrm... */
2762 }
2763 dname.hash = full_name_hash(dname.name, dname.len);
2764 dentry = d_lookup(parent, &dname);
2765 dput(parent);
2766 if (!dentry)
2767 goto release;
2768
2769 spin_lock(&dentry->d_lock);
2770 di = ceph_dentry(dentry);
2771 switch (h->action) {
2772 case CEPH_MDS_LEASE_REVOKE:
2773 if (di && di->lease_session == session) {
2774 if (ceph_seq_cmp(di->lease_seq, seq) > 0)
2775 h->seq = cpu_to_le32(di->lease_seq);
2776 __ceph_mdsc_drop_dentry_lease(dentry);
2777 }
2778 release = 1;
2779 break;
2780
2781 case CEPH_MDS_LEASE_RENEW:
2782 if (di && di->lease_session == session &&
2783 di->lease_gen == session->s_cap_gen &&
2784 di->lease_renew_from &&
2785 di->lease_renew_after == 0) {
2786 unsigned long duration =
2787 le32_to_cpu(h->duration_ms) * HZ / 1000;
2788
2789 di->lease_seq = seq;
2790 dentry->d_time = di->lease_renew_from + duration;
2791 di->lease_renew_after = di->lease_renew_from +
2792 (duration >> 1);
2793 di->lease_renew_from = 0;
2794 }
2795 break;
2796 }
2797 spin_unlock(&dentry->d_lock);
2798 dput(dentry);
2799
2800 if (!release)
2801 goto out;
2802
2803 release:
2804 /* let's just reuse the same message */
2805 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2806 ceph_msg_get(msg);
2807 ceph_con_send(&session->s_con, msg);
2808
2809 out:
2810 iput(inode);
2811 mutex_unlock(&session->s_mutex);
2812 return;
2813
2814 bad:
2815 pr_err("corrupt lease message\n");
2816 ceph_msg_dump(msg);
2817 }
2818
2819 void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
2820 struct inode *inode,
2821 struct dentry *dentry, char action,
2822 u32 seq)
2823 {
2824 struct ceph_msg *msg;
2825 struct ceph_mds_lease *lease;
2826 int len = sizeof(*lease) + sizeof(u32);
2827 int dnamelen = 0;
2828
2829 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
2830 inode, dentry, ceph_lease_op_name(action), session->s_mds);
2831 dnamelen = dentry->d_name.len;
2832 len += dnamelen;
2833
2834 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS);
2835 if (!msg)
2836 return;
2837 lease = msg->front.iov_base;
2838 lease->action = action;
2839 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
2840 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
2841 lease->seq = cpu_to_le32(seq);
2842 put_unaligned_le32(dnamelen, lease + 1);
2843 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
2844
2845 /*
2846 * if this is a preemptive lease RELEASE, no need to
2847 * flush request stream, since the actual request will
2848 * soon follow.
2849 */
2850 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
2851
2852 ceph_con_send(&session->s_con, msg);
2853 }
2854
2855 /*
2856 * Preemptively release a lease we expect to invalidate anyway.
2857 * Pass @inode always, @dentry is optional.
2858 */
2859 void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
2860 struct dentry *dentry)
2861 {
2862 struct ceph_dentry_info *di;
2863 struct ceph_mds_session *session;
2864 u32 seq;
2865
2866 BUG_ON(inode == NULL);
2867 BUG_ON(dentry == NULL);
2868
2869 /* is dentry lease valid? */
2870 spin_lock(&dentry->d_lock);
2871 di = ceph_dentry(dentry);
2872 if (!di || !di->lease_session ||
2873 di->lease_session->s_mds < 0 ||
2874 di->lease_gen != di->lease_session->s_cap_gen ||
2875 !time_before(jiffies, dentry->d_time)) {
2876 dout("lease_release inode %p dentry %p -- "
2877 "no lease\n",
2878 inode, dentry);
2879 spin_unlock(&dentry->d_lock);
2880 return;
2881 }
2882
2883 /* we do have a lease on this dentry; note mds and seq */
2884 session = ceph_get_mds_session(di->lease_session);
2885 seq = di->lease_seq;
2886 __ceph_mdsc_drop_dentry_lease(dentry);
2887 spin_unlock(&dentry->d_lock);
2888
2889 dout("lease_release inode %p dentry %p to mds%d\n",
2890 inode, dentry, session->s_mds);
2891 ceph_mdsc_lease_send_msg(session, inode, dentry,
2892 CEPH_MDS_LEASE_RELEASE, seq);
2893 ceph_put_mds_session(session);
2894 }
2895
2896 /*
2897 * drop all leases (and dentry refs) in preparation for umount
2898 */
2899 static void drop_leases(struct ceph_mds_client *mdsc)
2900 {
2901 int i;
2902
2903 dout("drop_leases\n");
2904 mutex_lock(&mdsc->mutex);
2905 for (i = 0; i < mdsc->max_sessions; i++) {
2906 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2907 if (!s)
2908 continue;
2909 mutex_unlock(&mdsc->mutex);
2910 mutex_lock(&s->s_mutex);
2911 mutex_unlock(&s->s_mutex);
2912 ceph_put_mds_session(s);
2913 mutex_lock(&mdsc->mutex);
2914 }
2915 mutex_unlock(&mdsc->mutex);
2916 }
2917
2918
2919
2920 /*
2921 * delayed work -- periodically trim expired leases, renew caps with mds
2922 */
2923 static void schedule_delayed(struct ceph_mds_client *mdsc)
2924 {
2925 int delay = 5;
2926 unsigned hz = round_jiffies_relative(HZ * delay);
2927 schedule_delayed_work(&mdsc->delayed_work, hz);
2928 }
2929
2930 static void delayed_work(struct work_struct *work)
2931 {
2932 int i;
2933 struct ceph_mds_client *mdsc =
2934 container_of(work, struct ceph_mds_client, delayed_work.work);
2935 int renew_interval;
2936 int renew_caps;
2937
2938 dout("mdsc delayed_work\n");
2939 ceph_check_delayed_caps(mdsc);
2940
2941 mutex_lock(&mdsc->mutex);
2942 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
2943 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
2944 mdsc->last_renew_caps);
2945 if (renew_caps)
2946 mdsc->last_renew_caps = jiffies;
2947
2948 for (i = 0; i < mdsc->max_sessions; i++) {
2949 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2950 if (s == NULL)
2951 continue;
2952 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
2953 dout("resending session close request for mds%d\n",
2954 s->s_mds);
2955 request_close_session(mdsc, s);
2956 ceph_put_mds_session(s);
2957 continue;
2958 }
2959 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
2960 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
2961 s->s_state = CEPH_MDS_SESSION_HUNG;
2962 pr_info("mds%d hung\n", s->s_mds);
2963 }
2964 }
2965 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
2966 /* this mds is failed or recovering, just wait */
2967 ceph_put_mds_session(s);
2968 continue;
2969 }
2970 mutex_unlock(&mdsc->mutex);
2971
2972 mutex_lock(&s->s_mutex);
2973 if (renew_caps)
2974 send_renew_caps(mdsc, s);
2975 else
2976 ceph_con_keepalive(&s->s_con);
2977 ceph_add_cap_releases(mdsc, s);
2978 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2979 s->s_state == CEPH_MDS_SESSION_HUNG)
2980 ceph_send_cap_releases(mdsc, s);
2981 mutex_unlock(&s->s_mutex);
2982 ceph_put_mds_session(s);
2983
2984 mutex_lock(&mdsc->mutex);
2985 }
2986 mutex_unlock(&mdsc->mutex);
2987
2988 schedule_delayed(mdsc);
2989 }
2990
2991 int ceph_mdsc_init(struct ceph_fs_client *fsc)
2992
2993 {
2994 struct ceph_mds_client *mdsc;
2995
2996 mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS);
2997 if (!mdsc)
2998 return -ENOMEM;
2999 mdsc->fsc = fsc;
3000 fsc->mdsc = mdsc;
3001 mutex_init(&mdsc->mutex);
3002 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
3003 if (mdsc->mdsmap == NULL)
3004 return -ENOMEM;
3005
3006 init_completion(&mdsc->safe_umount_waiters);
3007 init_waitqueue_head(&mdsc->session_close_wq);
3008 INIT_LIST_HEAD(&mdsc->waiting_for_map);
3009 mdsc->sessions = NULL;
3010 mdsc->max_sessions = 0;
3011 mdsc->stopping = 0;
3012 init_rwsem(&mdsc->snap_rwsem);
3013 mdsc->snap_realms = RB_ROOT;
3014 INIT_LIST_HEAD(&mdsc->snap_empty);
3015 spin_lock_init(&mdsc->snap_empty_lock);
3016 mdsc->last_tid = 0;
3017 mdsc->request_tree = RB_ROOT;
3018 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
3019 mdsc->last_renew_caps = jiffies;
3020 INIT_LIST_HEAD(&mdsc->cap_delay_list);
3021 spin_lock_init(&mdsc->cap_delay_lock);
3022 INIT_LIST_HEAD(&mdsc->snap_flush_list);
3023 spin_lock_init(&mdsc->snap_flush_lock);
3024 mdsc->cap_flush_seq = 0;
3025 INIT_LIST_HEAD(&mdsc->cap_dirty);
3026 INIT_LIST_HEAD(&mdsc->cap_dirty_migrating);
3027 mdsc->num_cap_flushing = 0;
3028 spin_lock_init(&mdsc->cap_dirty_lock);
3029 init_waitqueue_head(&mdsc->cap_flushing_wq);
3030 spin_lock_init(&mdsc->dentry_lru_lock);
3031 INIT_LIST_HEAD(&mdsc->dentry_lru);
3032
3033 ceph_caps_init(mdsc);
3034 ceph_adjust_min_caps(mdsc, fsc->min_caps);
3035
3036 return 0;
3037 }
3038
3039 /*
3040 * Wait for safe replies on open mds requests. If we time out, drop
3041 * all requests from the tree to avoid dangling dentry refs.
3042 */
3043 static void wait_requests(struct ceph_mds_client *mdsc)
3044 {
3045 struct ceph_mds_request *req;
3046 struct ceph_fs_client *fsc = mdsc->fsc;
3047
3048 mutex_lock(&mdsc->mutex);
3049 if (__get_oldest_req(mdsc)) {
3050 mutex_unlock(&mdsc->mutex);
3051
3052 dout("wait_requests waiting for requests\n");
3053 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
3054 fsc->client->options->mount_timeout * HZ);
3055
3056 /* tear down remaining requests */
3057 mutex_lock(&mdsc->mutex);
3058 while ((req = __get_oldest_req(mdsc))) {
3059 dout("wait_requests timed out on tid %llu\n",
3060 req->r_tid);
3061 __unregister_request(mdsc, req);
3062 }
3063 }
3064 mutex_unlock(&mdsc->mutex);
3065 dout("wait_requests done\n");
3066 }
3067
3068 /*
3069 * called before mount is ro, and before dentries are torn down.
3070 * (hmm, does this still race with new lookups?)
3071 */
3072 void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
3073 {
3074 dout("pre_umount\n");
3075 mdsc->stopping = 1;
3076
3077 drop_leases(mdsc);
3078 ceph_flush_dirty_caps(mdsc);
3079 wait_requests(mdsc);
3080
3081 /*
3082 * wait for reply handlers to drop their request refs and
3083 * their inode/dcache refs
3084 */
3085 ceph_msgr_flush();
3086 }
3087
3088 /*
3089 * wait for all write mds requests to flush.
3090 */
3091 static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
3092 {
3093 struct ceph_mds_request *req = NULL, *nextreq;
3094 struct rb_node *n;
3095
3096 mutex_lock(&mdsc->mutex);
3097 dout("wait_unsafe_requests want %lld\n", want_tid);
3098 restart:
3099 req = __get_oldest_req(mdsc);
3100 while (req && req->r_tid <= want_tid) {
3101 /* find next request */
3102 n = rb_next(&req->r_node);
3103 if (n)
3104 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
3105 else
3106 nextreq = NULL;
3107 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
3108 /* write op */
3109 ceph_mdsc_get_request(req);
3110 if (nextreq)
3111 ceph_mdsc_get_request(nextreq);
3112 mutex_unlock(&mdsc->mutex);
3113 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
3114 req->r_tid, want_tid);
3115 wait_for_completion(&req->r_safe_completion);
3116 mutex_lock(&mdsc->mutex);
3117 ceph_mdsc_put_request(req);
3118 if (!nextreq)
3119 break; /* next dne before, so we're done! */
3120 if (RB_EMPTY_NODE(&nextreq->r_node)) {
3121 /* next request was removed from tree */
3122 ceph_mdsc_put_request(nextreq);
3123 goto restart;
3124 }
3125 ceph_mdsc_put_request(nextreq); /* won't go away */
3126 }
3127 req = nextreq;
3128 }
3129 mutex_unlock(&mdsc->mutex);
3130 dout("wait_unsafe_requests done\n");
3131 }
3132
3133 void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
3134 {
3135 u64 want_tid, want_flush;
3136
3137 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3138 return;
3139
3140 dout("sync\n");
3141 mutex_lock(&mdsc->mutex);
3142 want_tid = mdsc->last_tid;
3143 want_flush = mdsc->cap_flush_seq;
3144 mutex_unlock(&mdsc->mutex);
3145 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
3146
3147 ceph_flush_dirty_caps(mdsc);
3148
3149 wait_unsafe_requests(mdsc, want_tid);
3150 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
3151 }
3152
3153 /*
3154 * true if all sessions are closed, or we force unmount
3155 */
3156 bool done_closing_sessions(struct ceph_mds_client *mdsc)
3157 {
3158 int i, n = 0;
3159
3160 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3161 return true;
3162
3163 mutex_lock(&mdsc->mutex);
3164 for (i = 0; i < mdsc->max_sessions; i++)
3165 if (mdsc->sessions[i])
3166 n++;
3167 mutex_unlock(&mdsc->mutex);
3168 return n == 0;
3169 }
3170
3171 /*
3172 * called after sb is ro.
3173 */
3174 void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
3175 {
3176 struct ceph_mds_session *session;
3177 int i;
3178 struct ceph_fs_client *fsc = mdsc->fsc;
3179 unsigned long timeout = fsc->client->options->mount_timeout * HZ;
3180
3181 dout("close_sessions\n");
3182
3183 /* close sessions */
3184 mutex_lock(&mdsc->mutex);
3185 for (i = 0; i < mdsc->max_sessions; i++) {
3186 session = __ceph_lookup_mds_session(mdsc, i);
3187 if (!session)
3188 continue;
3189 mutex_unlock(&mdsc->mutex);
3190 mutex_lock(&session->s_mutex);
3191 __close_session(mdsc, session);
3192 mutex_unlock(&session->s_mutex);
3193 ceph_put_mds_session(session);
3194 mutex_lock(&mdsc->mutex);
3195 }
3196 mutex_unlock(&mdsc->mutex);
3197
3198 dout("waiting for sessions to close\n");
3199 wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc),
3200 timeout);
3201
3202 /* tear down remaining sessions */
3203 mutex_lock(&mdsc->mutex);
3204 for (i = 0; i < mdsc->max_sessions; i++) {
3205 if (mdsc->sessions[i]) {
3206 session = get_session(mdsc->sessions[i]);
3207 __unregister_session(mdsc, session);
3208 mutex_unlock(&mdsc->mutex);
3209 mutex_lock(&session->s_mutex);
3210 remove_session_caps(session);
3211 mutex_unlock(&session->s_mutex);
3212 ceph_put_mds_session(session);
3213 mutex_lock(&mdsc->mutex);
3214 }
3215 }
3216 WARN_ON(!list_empty(&mdsc->cap_delay_list));
3217 mutex_unlock(&mdsc->mutex);
3218
3219 ceph_cleanup_empty_realms(mdsc);
3220
3221 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3222
3223 dout("stopped\n");
3224 }
3225
3226 static void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
3227 {
3228 dout("stop\n");
3229 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3230 if (mdsc->mdsmap)
3231 ceph_mdsmap_destroy(mdsc->mdsmap);
3232 kfree(mdsc->sessions);
3233 ceph_caps_finalize(mdsc);
3234 }
3235
3236 void ceph_mdsc_destroy(struct ceph_fs_client *fsc)
3237 {
3238 struct ceph_mds_client *mdsc = fsc->mdsc;
3239
3240 dout("mdsc_destroy %p\n", mdsc);
3241 ceph_mdsc_stop(mdsc);
3242
3243 /* flush out any connection work with references to us */
3244 ceph_msgr_flush();
3245
3246 fsc->mdsc = NULL;
3247 kfree(mdsc);
3248 dout("mdsc_destroy %p done\n", mdsc);
3249 }
3250
3251
3252 /*
3253 * handle mds map update.
3254 */
3255 void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3256 {
3257 u32 epoch;
3258 u32 maplen;
3259 void *p = msg->front.iov_base;
3260 void *end = p + msg->front.iov_len;
3261 struct ceph_mdsmap *newmap, *oldmap;
3262 struct ceph_fsid fsid;
3263 int err = -EINVAL;
3264
3265 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
3266 ceph_decode_copy(&p, &fsid, sizeof(fsid));
3267 if (ceph_check_fsid(mdsc->fsc->client, &fsid) < 0)
3268 return;
3269 epoch = ceph_decode_32(&p);
3270 maplen = ceph_decode_32(&p);
3271 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
3272
3273 /* do we need it? */
3274 ceph_monc_got_mdsmap(&mdsc->fsc->client->monc, epoch);
3275 mutex_lock(&mdsc->mutex);
3276 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
3277 dout("handle_map epoch %u <= our %u\n",
3278 epoch, mdsc->mdsmap->m_epoch);
3279 mutex_unlock(&mdsc->mutex);
3280 return;
3281 }
3282
3283 newmap = ceph_mdsmap_decode(&p, end);
3284 if (IS_ERR(newmap)) {
3285 err = PTR_ERR(newmap);
3286 goto bad_unlock;
3287 }
3288
3289 /* swap into place */
3290 if (mdsc->mdsmap) {
3291 oldmap = mdsc->mdsmap;
3292 mdsc->mdsmap = newmap;
3293 check_new_map(mdsc, newmap, oldmap);
3294 ceph_mdsmap_destroy(oldmap);
3295 } else {
3296 mdsc->mdsmap = newmap; /* first mds map */
3297 }
3298 mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
3299
3300 __wake_requests(mdsc, &mdsc->waiting_for_map);
3301
3302 mutex_unlock(&mdsc->mutex);
3303 schedule_delayed(mdsc);
3304 return;
3305
3306 bad_unlock:
3307 mutex_unlock(&mdsc->mutex);
3308 bad:
3309 pr_err("error decoding mdsmap %d\n", err);
3310 return;
3311 }
3312
3313 static struct ceph_connection *con_get(struct ceph_connection *con)
3314 {
3315 struct ceph_mds_session *s = con->private;
3316
3317 if (get_session(s)) {
3318 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
3319 return con;
3320 }
3321 dout("mdsc con_get %p FAIL\n", s);
3322 return NULL;
3323 }
3324
3325 static void con_put(struct ceph_connection *con)
3326 {
3327 struct ceph_mds_session *s = con->private;
3328
3329 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref) - 1);
3330 ceph_put_mds_session(s);
3331 }
3332
3333 /*
3334 * if the client is unresponsive for long enough, the mds will kill
3335 * the session entirely.
3336 */
3337 static void peer_reset(struct ceph_connection *con)
3338 {
3339 struct ceph_mds_session *s = con->private;
3340 struct ceph_mds_client *mdsc = s->s_mdsc;
3341
3342 pr_warning("mds%d closed our session\n", s->s_mds);
3343 send_mds_reconnect(mdsc, s);
3344 }
3345
3346 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
3347 {
3348 struct ceph_mds_session *s = con->private;
3349 struct ceph_mds_client *mdsc = s->s_mdsc;
3350 int type = le16_to_cpu(msg->hdr.type);
3351
3352 mutex_lock(&mdsc->mutex);
3353 if (__verify_registered_session(mdsc, s) < 0) {
3354 mutex_unlock(&mdsc->mutex);
3355 goto out;
3356 }
3357 mutex_unlock(&mdsc->mutex);
3358
3359 switch (type) {
3360 case CEPH_MSG_MDS_MAP:
3361 ceph_mdsc_handle_map(mdsc, msg);
3362 break;
3363 case CEPH_MSG_CLIENT_SESSION:
3364 handle_session(s, msg);
3365 break;
3366 case CEPH_MSG_CLIENT_REPLY:
3367 handle_reply(s, msg);
3368 break;
3369 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
3370 handle_forward(mdsc, s, msg);
3371 break;
3372 case CEPH_MSG_CLIENT_CAPS:
3373 ceph_handle_caps(s, msg);
3374 break;
3375 case CEPH_MSG_CLIENT_SNAP:
3376 ceph_handle_snap(mdsc, s, msg);
3377 break;
3378 case CEPH_MSG_CLIENT_LEASE:
3379 handle_lease(mdsc, s, msg);
3380 break;
3381
3382 default:
3383 pr_err("received unknown message type %d %s\n", type,
3384 ceph_msg_type_name(type));
3385 }
3386 out:
3387 ceph_msg_put(msg);
3388 }
3389
3390 /*
3391 * authentication
3392 */
3393 static int get_authorizer(struct ceph_connection *con,
3394 void **buf, int *len, int *proto,
3395 void **reply_buf, int *reply_len, int force_new)
3396 {
3397 struct ceph_mds_session *s = con->private;
3398 struct ceph_mds_client *mdsc = s->s_mdsc;
3399 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3400 int ret = 0;
3401
3402 if (force_new && s->s_authorizer) {
3403 ac->ops->destroy_authorizer(ac, s->s_authorizer);
3404 s->s_authorizer = NULL;
3405 }
3406 if (s->s_authorizer == NULL) {
3407 if (ac->ops->create_authorizer) {
3408 ret = ac->ops->create_authorizer(
3409 ac, CEPH_ENTITY_TYPE_MDS,
3410 &s->s_authorizer,
3411 &s->s_authorizer_buf,
3412 &s->s_authorizer_buf_len,
3413 &s->s_authorizer_reply_buf,
3414 &s->s_authorizer_reply_buf_len);
3415 if (ret)
3416 return ret;
3417 }
3418 }
3419
3420 *proto = ac->protocol;
3421 *buf = s->s_authorizer_buf;
3422 *len = s->s_authorizer_buf_len;
3423 *reply_buf = s->s_authorizer_reply_buf;
3424 *reply_len = s->s_authorizer_reply_buf_len;
3425 return 0;
3426 }
3427
3428
3429 static int verify_authorizer_reply(struct ceph_connection *con, int len)
3430 {
3431 struct ceph_mds_session *s = con->private;
3432 struct ceph_mds_client *mdsc = s->s_mdsc;
3433 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3434
3435 return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
3436 }
3437
3438 static int invalidate_authorizer(struct ceph_connection *con)
3439 {
3440 struct ceph_mds_session *s = con->private;
3441 struct ceph_mds_client *mdsc = s->s_mdsc;
3442 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3443
3444 if (ac->ops->invalidate_authorizer)
3445 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3446
3447 return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
3448 }
3449
3450 static const struct ceph_connection_operations mds_con_ops = {
3451 .get = con_get,
3452 .put = con_put,
3453 .dispatch = dispatch,
3454 .get_authorizer = get_authorizer,
3455 .verify_authorizer_reply = verify_authorizer_reply,
3456 .invalidate_authorizer = invalidate_authorizer,
3457 .peer_reset = peer_reset,
3458 };
3459
3460 /* eof */
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