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41 * are no longer valid.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