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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi...
[mirror_ubuntu-artful-kernel.git] / fs / ceph / mds_client.c
1 #include <linux/ceph/ceph_debug.h>
2
3 #include <linux/fs.h>
4 #include <linux/wait.h>
5 #include <linux/slab.h>
6 #include <linux/gfp.h>
7 #include <linux/sched.h>
8 #include <linux/debugfs.h>
9 #include <linux/seq_file.h>
10 #include <linux/utsname.h>
11 #include <linux/ratelimit.h>
12
13 #include "super.h"
14 #include "mds_client.h"
15
16 #include <linux/ceph/ceph_features.h>
17 #include <linux/ceph/messenger.h>
18 #include <linux/ceph/decode.h>
19 #include <linux/ceph/pagelist.h>
20 #include <linux/ceph/auth.h>
21 #include <linux/ceph/debugfs.h>
22
23 /*
24 * A cluster of MDS (metadata server) daemons is responsible for
25 * managing the file system namespace (the directory hierarchy and
26 * inodes) and for coordinating shared access to storage. Metadata is
27 * partitioning hierarchically across a number of servers, and that
28 * partition varies over time as the cluster adjusts the distribution
29 * in order to balance load.
30 *
31 * The MDS client is primarily responsible to managing synchronous
32 * metadata requests for operations like open, unlink, and so forth.
33 * If there is a MDS failure, we find out about it when we (possibly
34 * request and) receive a new MDS map, and can resubmit affected
35 * requests.
36 *
37 * For the most part, though, we take advantage of a lossless
38 * communications channel to the MDS, and do not need to worry about
39 * timing out or resubmitting requests.
40 *
41 * We maintain a stateful "session" with each MDS we interact with.
42 * Within each session, we sent periodic heartbeat messages to ensure
43 * any capabilities or leases we have been issues remain valid. If
44 * the session times out and goes stale, our leases and capabilities
45 * are no longer valid.
46 */
47
48 struct ceph_reconnect_state {
49 int nr_caps;
50 struct ceph_pagelist *pagelist;
51 unsigned msg_version;
52 };
53
54 static void __wake_requests(struct ceph_mds_client *mdsc,
55 struct list_head *head);
56
57 static const struct ceph_connection_operations mds_con_ops;
58
59
60 /*
61 * mds reply parsing
62 */
63
64 /*
65 * parse individual inode info
66 */
67 static int parse_reply_info_in(void **p, void *end,
68 struct ceph_mds_reply_info_in *info,
69 u64 features)
70 {
71 int err = -EIO;
72
73 info->in = *p;
74 *p += sizeof(struct ceph_mds_reply_inode) +
75 sizeof(*info->in->fragtree.splits) *
76 le32_to_cpu(info->in->fragtree.nsplits);
77
78 ceph_decode_32_safe(p, end, info->symlink_len, bad);
79 ceph_decode_need(p, end, info->symlink_len, bad);
80 info->symlink = *p;
81 *p += info->symlink_len;
82
83 if (features & CEPH_FEATURE_DIRLAYOUTHASH)
84 ceph_decode_copy_safe(p, end, &info->dir_layout,
85 sizeof(info->dir_layout), bad);
86 else
87 memset(&info->dir_layout, 0, sizeof(info->dir_layout));
88
89 ceph_decode_32_safe(p, end, info->xattr_len, bad);
90 ceph_decode_need(p, end, info->xattr_len, bad);
91 info->xattr_data = *p;
92 *p += info->xattr_len;
93
94 if (features & CEPH_FEATURE_MDS_INLINE_DATA) {
95 ceph_decode_64_safe(p, end, info->inline_version, bad);
96 ceph_decode_32_safe(p, end, info->inline_len, bad);
97 ceph_decode_need(p, end, info->inline_len, bad);
98 info->inline_data = *p;
99 *p += info->inline_len;
100 } else
101 info->inline_version = CEPH_INLINE_NONE;
102
103 info->pool_ns_len = 0;
104 info->pool_ns_data = NULL;
105 if (features & CEPH_FEATURE_FS_FILE_LAYOUT_V2) {
106 ceph_decode_32_safe(p, end, info->pool_ns_len, bad);
107 if (info->pool_ns_len > 0) {
108 ceph_decode_need(p, end, info->pool_ns_len, bad);
109 info->pool_ns_data = *p;
110 *p += info->pool_ns_len;
111 }
112 }
113
114 return 0;
115 bad:
116 return err;
117 }
118
119 /*
120 * parse a normal reply, which may contain a (dir+)dentry and/or a
121 * target inode.
122 */
123 static int parse_reply_info_trace(void **p, void *end,
124 struct ceph_mds_reply_info_parsed *info,
125 u64 features)
126 {
127 int err;
128
129 if (info->head->is_dentry) {
130 err = parse_reply_info_in(p, end, &info->diri, features);
131 if (err < 0)
132 goto out_bad;
133
134 if (unlikely(*p + sizeof(*info->dirfrag) > end))
135 goto bad;
136 info->dirfrag = *p;
137 *p += sizeof(*info->dirfrag) +
138 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
139 if (unlikely(*p > end))
140 goto bad;
141
142 ceph_decode_32_safe(p, end, info->dname_len, bad);
143 ceph_decode_need(p, end, info->dname_len, bad);
144 info->dname = *p;
145 *p += info->dname_len;
146 info->dlease = *p;
147 *p += sizeof(*info->dlease);
148 }
149
150 if (info->head->is_target) {
151 err = parse_reply_info_in(p, end, &info->targeti, features);
152 if (err < 0)
153 goto out_bad;
154 }
155
156 if (unlikely(*p != end))
157 goto bad;
158 return 0;
159
160 bad:
161 err = -EIO;
162 out_bad:
163 pr_err("problem parsing mds trace %d\n", err);
164 return err;
165 }
166
167 /*
168 * parse readdir results
169 */
170 static int parse_reply_info_dir(void **p, void *end,
171 struct ceph_mds_reply_info_parsed *info,
172 u64 features)
173 {
174 u32 num, i = 0;
175 int err;
176
177 info->dir_dir = *p;
178 if (*p + sizeof(*info->dir_dir) > end)
179 goto bad;
180 *p += sizeof(*info->dir_dir) +
181 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
182 if (*p > end)
183 goto bad;
184
185 ceph_decode_need(p, end, sizeof(num) + 2, bad);
186 num = ceph_decode_32(p);
187 {
188 u16 flags = ceph_decode_16(p);
189 info->dir_end = !!(flags & CEPH_READDIR_FRAG_END);
190 info->dir_complete = !!(flags & CEPH_READDIR_FRAG_COMPLETE);
191 info->hash_order = !!(flags & CEPH_READDIR_HASH_ORDER);
192 info->offset_hash = !!(flags & CEPH_READDIR_OFFSET_HASH);
193 }
194 if (num == 0)
195 goto done;
196
197 BUG_ON(!info->dir_entries);
198 if ((unsigned long)(info->dir_entries + num) >
199 (unsigned long)info->dir_entries + info->dir_buf_size) {
200 pr_err("dir contents are larger than expected\n");
201 WARN_ON(1);
202 goto bad;
203 }
204
205 info->dir_nr = num;
206 while (num) {
207 struct ceph_mds_reply_dir_entry *rde = info->dir_entries + i;
208 /* dentry */
209 ceph_decode_need(p, end, sizeof(u32)*2, bad);
210 rde->name_len = ceph_decode_32(p);
211 ceph_decode_need(p, end, rde->name_len, bad);
212 rde->name = *p;
213 *p += rde->name_len;
214 dout("parsed dir dname '%.*s'\n", rde->name_len, rde->name);
215 rde->lease = *p;
216 *p += sizeof(struct ceph_mds_reply_lease);
217
218 /* inode */
219 err = parse_reply_info_in(p, end, &rde->inode, features);
220 if (err < 0)
221 goto out_bad;
222 /* ceph_readdir_prepopulate() will update it */
223 rde->offset = 0;
224 i++;
225 num--;
226 }
227
228 done:
229 if (*p != end)
230 goto bad;
231 return 0;
232
233 bad:
234 err = -EIO;
235 out_bad:
236 pr_err("problem parsing dir contents %d\n", err);
237 return err;
238 }
239
240 /*
241 * parse fcntl F_GETLK results
242 */
243 static int parse_reply_info_filelock(void **p, void *end,
244 struct ceph_mds_reply_info_parsed *info,
245 u64 features)
246 {
247 if (*p + sizeof(*info->filelock_reply) > end)
248 goto bad;
249
250 info->filelock_reply = *p;
251 *p += sizeof(*info->filelock_reply);
252
253 if (unlikely(*p != end))
254 goto bad;
255 return 0;
256
257 bad:
258 return -EIO;
259 }
260
261 /*
262 * parse create results
263 */
264 static int parse_reply_info_create(void **p, void *end,
265 struct ceph_mds_reply_info_parsed *info,
266 u64 features)
267 {
268 if (features & CEPH_FEATURE_REPLY_CREATE_INODE) {
269 if (*p == end) {
270 info->has_create_ino = false;
271 } else {
272 info->has_create_ino = true;
273 info->ino = ceph_decode_64(p);
274 }
275 }
276
277 if (unlikely(*p != end))
278 goto bad;
279 return 0;
280
281 bad:
282 return -EIO;
283 }
284
285 /*
286 * parse extra results
287 */
288 static int parse_reply_info_extra(void **p, void *end,
289 struct ceph_mds_reply_info_parsed *info,
290 u64 features)
291 {
292 u32 op = le32_to_cpu(info->head->op);
293
294 if (op == CEPH_MDS_OP_GETFILELOCK)
295 return parse_reply_info_filelock(p, end, info, features);
296 else if (op == CEPH_MDS_OP_READDIR || op == CEPH_MDS_OP_LSSNAP)
297 return parse_reply_info_dir(p, end, info, features);
298 else if (op == CEPH_MDS_OP_CREATE)
299 return parse_reply_info_create(p, end, info, features);
300 else
301 return -EIO;
302 }
303
304 /*
305 * parse entire mds reply
306 */
307 static int parse_reply_info(struct ceph_msg *msg,
308 struct ceph_mds_reply_info_parsed *info,
309 u64 features)
310 {
311 void *p, *end;
312 u32 len;
313 int err;
314
315 info->head = msg->front.iov_base;
316 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
317 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
318
319 /* trace */
320 ceph_decode_32_safe(&p, end, len, bad);
321 if (len > 0) {
322 ceph_decode_need(&p, end, len, bad);
323 err = parse_reply_info_trace(&p, p+len, info, features);
324 if (err < 0)
325 goto out_bad;
326 }
327
328 /* extra */
329 ceph_decode_32_safe(&p, end, len, bad);
330 if (len > 0) {
331 ceph_decode_need(&p, end, len, bad);
332 err = parse_reply_info_extra(&p, p+len, info, features);
333 if (err < 0)
334 goto out_bad;
335 }
336
337 /* snap blob */
338 ceph_decode_32_safe(&p, end, len, bad);
339 info->snapblob_len = len;
340 info->snapblob = p;
341 p += len;
342
343 if (p != end)
344 goto bad;
345 return 0;
346
347 bad:
348 err = -EIO;
349 out_bad:
350 pr_err("mds parse_reply err %d\n", err);
351 return err;
352 }
353
354 static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
355 {
356 if (!info->dir_entries)
357 return;
358 free_pages((unsigned long)info->dir_entries, get_order(info->dir_buf_size));
359 }
360
361
362 /*
363 * sessions
364 */
365 const char *ceph_session_state_name(int s)
366 {
367 switch (s) {
368 case CEPH_MDS_SESSION_NEW: return "new";
369 case CEPH_MDS_SESSION_OPENING: return "opening";
370 case CEPH_MDS_SESSION_OPEN: return "open";
371 case CEPH_MDS_SESSION_HUNG: return "hung";
372 case CEPH_MDS_SESSION_CLOSING: return "closing";
373 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
374 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
375 case CEPH_MDS_SESSION_REJECTED: return "rejected";
376 default: return "???";
377 }
378 }
379
380 static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
381 {
382 if (refcount_inc_not_zero(&s->s_ref)) {
383 dout("mdsc get_session %p %d -> %d\n", s,
384 refcount_read(&s->s_ref)-1, refcount_read(&s->s_ref));
385 return s;
386 } else {
387 dout("mdsc get_session %p 0 -- FAIL", s);
388 return NULL;
389 }
390 }
391
392 void ceph_put_mds_session(struct ceph_mds_session *s)
393 {
394 dout("mdsc put_session %p %d -> %d\n", s,
395 refcount_read(&s->s_ref), refcount_read(&s->s_ref)-1);
396 if (refcount_dec_and_test(&s->s_ref)) {
397 if (s->s_auth.authorizer)
398 ceph_auth_destroy_authorizer(s->s_auth.authorizer);
399 kfree(s);
400 }
401 }
402
403 /*
404 * called under mdsc->mutex
405 */
406 struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
407 int mds)
408 {
409 struct ceph_mds_session *session;
410
411 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
412 return NULL;
413 session = mdsc->sessions[mds];
414 dout("lookup_mds_session %p %d\n", session,
415 refcount_read(&session->s_ref));
416 get_session(session);
417 return session;
418 }
419
420 static bool __have_session(struct ceph_mds_client *mdsc, int mds)
421 {
422 if (mds >= mdsc->max_sessions)
423 return false;
424 return mdsc->sessions[mds];
425 }
426
427 static int __verify_registered_session(struct ceph_mds_client *mdsc,
428 struct ceph_mds_session *s)
429 {
430 if (s->s_mds >= mdsc->max_sessions ||
431 mdsc->sessions[s->s_mds] != s)
432 return -ENOENT;
433 return 0;
434 }
435
436 /*
437 * create+register a new session for given mds.
438 * called under mdsc->mutex.
439 */
440 static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
441 int mds)
442 {
443 struct ceph_mds_session *s;
444
445 if (mds >= mdsc->mdsmap->m_num_mds)
446 return ERR_PTR(-EINVAL);
447
448 s = kzalloc(sizeof(*s), GFP_NOFS);
449 if (!s)
450 return ERR_PTR(-ENOMEM);
451 s->s_mdsc = mdsc;
452 s->s_mds = mds;
453 s->s_state = CEPH_MDS_SESSION_NEW;
454 s->s_ttl = 0;
455 s->s_seq = 0;
456 mutex_init(&s->s_mutex);
457
458 ceph_con_init(&s->s_con, s, &mds_con_ops, &mdsc->fsc->client->msgr);
459
460 spin_lock_init(&s->s_gen_ttl_lock);
461 s->s_cap_gen = 0;
462 s->s_cap_ttl = jiffies - 1;
463
464 spin_lock_init(&s->s_cap_lock);
465 s->s_renew_requested = 0;
466 s->s_renew_seq = 0;
467 INIT_LIST_HEAD(&s->s_caps);
468 s->s_nr_caps = 0;
469 s->s_trim_caps = 0;
470 refcount_set(&s->s_ref, 1);
471 INIT_LIST_HEAD(&s->s_waiting);
472 INIT_LIST_HEAD(&s->s_unsafe);
473 s->s_num_cap_releases = 0;
474 s->s_cap_reconnect = 0;
475 s->s_cap_iterator = NULL;
476 INIT_LIST_HEAD(&s->s_cap_releases);
477 INIT_LIST_HEAD(&s->s_cap_flushing);
478
479 dout("register_session mds%d\n", mds);
480 if (mds >= mdsc->max_sessions) {
481 int newmax = 1 << get_count_order(mds+1);
482 struct ceph_mds_session **sa;
483
484 dout("register_session realloc to %d\n", newmax);
485 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
486 if (sa == NULL)
487 goto fail_realloc;
488 if (mdsc->sessions) {
489 memcpy(sa, mdsc->sessions,
490 mdsc->max_sessions * sizeof(void *));
491 kfree(mdsc->sessions);
492 }
493 mdsc->sessions = sa;
494 mdsc->max_sessions = newmax;
495 }
496 mdsc->sessions[mds] = s;
497 atomic_inc(&mdsc->num_sessions);
498 refcount_inc(&s->s_ref); /* one ref to sessions[], one to caller */
499
500 ceph_con_open(&s->s_con, CEPH_ENTITY_TYPE_MDS, mds,
501 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
502
503 return s;
504
505 fail_realloc:
506 kfree(s);
507 return ERR_PTR(-ENOMEM);
508 }
509
510 /*
511 * called under mdsc->mutex
512 */
513 static void __unregister_session(struct ceph_mds_client *mdsc,
514 struct ceph_mds_session *s)
515 {
516 dout("__unregister_session mds%d %p\n", s->s_mds, s);
517 BUG_ON(mdsc->sessions[s->s_mds] != s);
518 mdsc->sessions[s->s_mds] = NULL;
519 ceph_con_close(&s->s_con);
520 ceph_put_mds_session(s);
521 atomic_dec(&mdsc->num_sessions);
522 }
523
524 /*
525 * drop session refs in request.
526 *
527 * should be last request ref, or hold mdsc->mutex
528 */
529 static void put_request_session(struct ceph_mds_request *req)
530 {
531 if (req->r_session) {
532 ceph_put_mds_session(req->r_session);
533 req->r_session = NULL;
534 }
535 }
536
537 void ceph_mdsc_release_request(struct kref *kref)
538 {
539 struct ceph_mds_request *req = container_of(kref,
540 struct ceph_mds_request,
541 r_kref);
542 destroy_reply_info(&req->r_reply_info);
543 if (req->r_request)
544 ceph_msg_put(req->r_request);
545 if (req->r_reply)
546 ceph_msg_put(req->r_reply);
547 if (req->r_inode) {
548 ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
549 iput(req->r_inode);
550 }
551 if (req->r_parent)
552 ceph_put_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
553 iput(req->r_target_inode);
554 if (req->r_dentry)
555 dput(req->r_dentry);
556 if (req->r_old_dentry)
557 dput(req->r_old_dentry);
558 if (req->r_old_dentry_dir) {
559 /*
560 * track (and drop pins for) r_old_dentry_dir
561 * separately, since r_old_dentry's d_parent may have
562 * changed between the dir mutex being dropped and
563 * this request being freed.
564 */
565 ceph_put_cap_refs(ceph_inode(req->r_old_dentry_dir),
566 CEPH_CAP_PIN);
567 iput(req->r_old_dentry_dir);
568 }
569 kfree(req->r_path1);
570 kfree(req->r_path2);
571 if (req->r_pagelist)
572 ceph_pagelist_release(req->r_pagelist);
573 put_request_session(req);
574 ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation);
575 kfree(req);
576 }
577
578 DEFINE_RB_FUNCS(request, struct ceph_mds_request, r_tid, r_node)
579
580 /*
581 * lookup session, bump ref if found.
582 *
583 * called under mdsc->mutex.
584 */
585 static struct ceph_mds_request *
586 lookup_get_request(struct ceph_mds_client *mdsc, u64 tid)
587 {
588 struct ceph_mds_request *req;
589
590 req = lookup_request(&mdsc->request_tree, tid);
591 if (req)
592 ceph_mdsc_get_request(req);
593
594 return req;
595 }
596
597 /*
598 * Register an in-flight request, and assign a tid. Link to directory
599 * are modifying (if any).
600 *
601 * Called under mdsc->mutex.
602 */
603 static void __register_request(struct ceph_mds_client *mdsc,
604 struct ceph_mds_request *req,
605 struct inode *dir)
606 {
607 req->r_tid = ++mdsc->last_tid;
608 if (req->r_num_caps)
609 ceph_reserve_caps(mdsc, &req->r_caps_reservation,
610 req->r_num_caps);
611 dout("__register_request %p tid %lld\n", req, req->r_tid);
612 ceph_mdsc_get_request(req);
613 insert_request(&mdsc->request_tree, req);
614
615 req->r_uid = current_fsuid();
616 req->r_gid = current_fsgid();
617
618 if (mdsc->oldest_tid == 0 && req->r_op != CEPH_MDS_OP_SETFILELOCK)
619 mdsc->oldest_tid = req->r_tid;
620
621 if (dir) {
622 ihold(dir);
623 req->r_unsafe_dir = dir;
624 }
625 }
626
627 static void __unregister_request(struct ceph_mds_client *mdsc,
628 struct ceph_mds_request *req)
629 {
630 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
631
632 /* Never leave an unregistered request on an unsafe list! */
633 list_del_init(&req->r_unsafe_item);
634
635 if (req->r_tid == mdsc->oldest_tid) {
636 struct rb_node *p = rb_next(&req->r_node);
637 mdsc->oldest_tid = 0;
638 while (p) {
639 struct ceph_mds_request *next_req =
640 rb_entry(p, struct ceph_mds_request, r_node);
641 if (next_req->r_op != CEPH_MDS_OP_SETFILELOCK) {
642 mdsc->oldest_tid = next_req->r_tid;
643 break;
644 }
645 p = rb_next(p);
646 }
647 }
648
649 erase_request(&mdsc->request_tree, req);
650
651 if (req->r_unsafe_dir &&
652 test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
653 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
654 spin_lock(&ci->i_unsafe_lock);
655 list_del_init(&req->r_unsafe_dir_item);
656 spin_unlock(&ci->i_unsafe_lock);
657 }
658 if (req->r_target_inode &&
659 test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
660 struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
661 spin_lock(&ci->i_unsafe_lock);
662 list_del_init(&req->r_unsafe_target_item);
663 spin_unlock(&ci->i_unsafe_lock);
664 }
665
666 if (req->r_unsafe_dir) {
667 iput(req->r_unsafe_dir);
668 req->r_unsafe_dir = NULL;
669 }
670
671 complete_all(&req->r_safe_completion);
672
673 ceph_mdsc_put_request(req);
674 }
675
676 /*
677 * Walk back up the dentry tree until we hit a dentry representing a
678 * non-snapshot inode. We do this using the rcu_read_lock (which must be held
679 * when calling this) to ensure that the objects won't disappear while we're
680 * working with them. Once we hit a candidate dentry, we attempt to take a
681 * reference to it, and return that as the result.
682 */
683 static struct inode *get_nonsnap_parent(struct dentry *dentry)
684 {
685 struct inode *inode = NULL;
686
687 while (dentry && !IS_ROOT(dentry)) {
688 inode = d_inode_rcu(dentry);
689 if (!inode || ceph_snap(inode) == CEPH_NOSNAP)
690 break;
691 dentry = dentry->d_parent;
692 }
693 if (inode)
694 inode = igrab(inode);
695 return inode;
696 }
697
698 /*
699 * Choose mds to send request to next. If there is a hint set in the
700 * request (e.g., due to a prior forward hint from the mds), use that.
701 * Otherwise, consult frag tree and/or caps to identify the
702 * appropriate mds. If all else fails, choose randomly.
703 *
704 * Called under mdsc->mutex.
705 */
706 static int __choose_mds(struct ceph_mds_client *mdsc,
707 struct ceph_mds_request *req)
708 {
709 struct inode *inode;
710 struct ceph_inode_info *ci;
711 struct ceph_cap *cap;
712 int mode = req->r_direct_mode;
713 int mds = -1;
714 u32 hash = req->r_direct_hash;
715 bool is_hash = test_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
716
717 /*
718 * is there a specific mds we should try? ignore hint if we have
719 * no session and the mds is not up (active or recovering).
720 */
721 if (req->r_resend_mds >= 0 &&
722 (__have_session(mdsc, req->r_resend_mds) ||
723 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
724 dout("choose_mds using resend_mds mds%d\n",
725 req->r_resend_mds);
726 return req->r_resend_mds;
727 }
728
729 if (mode == USE_RANDOM_MDS)
730 goto random;
731
732 inode = NULL;
733 if (req->r_inode) {
734 inode = req->r_inode;
735 ihold(inode);
736 } else if (req->r_dentry) {
737 /* ignore race with rename; old or new d_parent is okay */
738 struct dentry *parent;
739 struct inode *dir;
740
741 rcu_read_lock();
742 parent = req->r_dentry->d_parent;
743 dir = req->r_parent ? : d_inode_rcu(parent);
744
745 if (!dir || dir->i_sb != mdsc->fsc->sb) {
746 /* not this fs or parent went negative */
747 inode = d_inode(req->r_dentry);
748 if (inode)
749 ihold(inode);
750 } else if (ceph_snap(dir) != CEPH_NOSNAP) {
751 /* direct snapped/virtual snapdir requests
752 * based on parent dir inode */
753 inode = get_nonsnap_parent(parent);
754 dout("__choose_mds using nonsnap parent %p\n", inode);
755 } else {
756 /* dentry target */
757 inode = d_inode(req->r_dentry);
758 if (!inode || mode == USE_AUTH_MDS) {
759 /* dir + name */
760 inode = igrab(dir);
761 hash = ceph_dentry_hash(dir, req->r_dentry);
762 is_hash = true;
763 } else {
764 ihold(inode);
765 }
766 }
767 rcu_read_unlock();
768 }
769
770 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
771 (int)hash, mode);
772 if (!inode)
773 goto random;
774 ci = ceph_inode(inode);
775
776 if (is_hash && S_ISDIR(inode->i_mode)) {
777 struct ceph_inode_frag frag;
778 int found;
779
780 ceph_choose_frag(ci, hash, &frag, &found);
781 if (found) {
782 if (mode == USE_ANY_MDS && frag.ndist > 0) {
783 u8 r;
784
785 /* choose a random replica */
786 get_random_bytes(&r, 1);
787 r %= frag.ndist;
788 mds = frag.dist[r];
789 dout("choose_mds %p %llx.%llx "
790 "frag %u mds%d (%d/%d)\n",
791 inode, ceph_vinop(inode),
792 frag.frag, mds,
793 (int)r, frag.ndist);
794 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
795 CEPH_MDS_STATE_ACTIVE)
796 goto out;
797 }
798
799 /* since this file/dir wasn't known to be
800 * replicated, then we want to look for the
801 * authoritative mds. */
802 mode = USE_AUTH_MDS;
803 if (frag.mds >= 0) {
804 /* choose auth mds */
805 mds = frag.mds;
806 dout("choose_mds %p %llx.%llx "
807 "frag %u mds%d (auth)\n",
808 inode, ceph_vinop(inode), frag.frag, mds);
809 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
810 CEPH_MDS_STATE_ACTIVE)
811 goto out;
812 }
813 }
814 }
815
816 spin_lock(&ci->i_ceph_lock);
817 cap = NULL;
818 if (mode == USE_AUTH_MDS)
819 cap = ci->i_auth_cap;
820 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
821 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
822 if (!cap) {
823 spin_unlock(&ci->i_ceph_lock);
824 iput(inode);
825 goto random;
826 }
827 mds = cap->session->s_mds;
828 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
829 inode, ceph_vinop(inode), mds,
830 cap == ci->i_auth_cap ? "auth " : "", cap);
831 spin_unlock(&ci->i_ceph_lock);
832 out:
833 iput(inode);
834 return mds;
835
836 random:
837 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
838 dout("choose_mds chose random mds%d\n", mds);
839 return mds;
840 }
841
842
843 /*
844 * session messages
845 */
846 static struct ceph_msg *create_session_msg(u32 op, u64 seq)
847 {
848 struct ceph_msg *msg;
849 struct ceph_mds_session_head *h;
850
851 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS,
852 false);
853 if (!msg) {
854 pr_err("create_session_msg ENOMEM creating msg\n");
855 return NULL;
856 }
857 h = msg->front.iov_base;
858 h->op = cpu_to_le32(op);
859 h->seq = cpu_to_le64(seq);
860
861 return msg;
862 }
863
864 /*
865 * session message, specialization for CEPH_SESSION_REQUEST_OPEN
866 * to include additional client metadata fields.
867 */
868 static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u64 seq)
869 {
870 struct ceph_msg *msg;
871 struct ceph_mds_session_head *h;
872 int i = -1;
873 int metadata_bytes = 0;
874 int metadata_key_count = 0;
875 struct ceph_options *opt = mdsc->fsc->client->options;
876 struct ceph_mount_options *fsopt = mdsc->fsc->mount_options;
877 void *p;
878
879 const char* metadata[][2] = {
880 {"hostname", utsname()->nodename},
881 {"kernel_version", utsname()->release},
882 {"entity_id", opt->name ? : ""},
883 {"root", fsopt->server_path ? : "/"},
884 {NULL, NULL}
885 };
886
887 /* Calculate serialized length of metadata */
888 metadata_bytes = 4; /* map length */
889 for (i = 0; metadata[i][0] != NULL; ++i) {
890 metadata_bytes += 8 + strlen(metadata[i][0]) +
891 strlen(metadata[i][1]);
892 metadata_key_count++;
893 }
894
895 /* Allocate the message */
896 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + metadata_bytes,
897 GFP_NOFS, false);
898 if (!msg) {
899 pr_err("create_session_msg ENOMEM creating msg\n");
900 return NULL;
901 }
902 h = msg->front.iov_base;
903 h->op = cpu_to_le32(CEPH_SESSION_REQUEST_OPEN);
904 h->seq = cpu_to_le64(seq);
905
906 /*
907 * Serialize client metadata into waiting buffer space, using
908 * the format that userspace expects for map<string, string>
909 *
910 * ClientSession messages with metadata are v2
911 */
912 msg->hdr.version = cpu_to_le16(2);
913 msg->hdr.compat_version = cpu_to_le16(1);
914
915 /* The write pointer, following the session_head structure */
916 p = msg->front.iov_base + sizeof(*h);
917
918 /* Number of entries in the map */
919 ceph_encode_32(&p, metadata_key_count);
920
921 /* Two length-prefixed strings for each entry in the map */
922 for (i = 0; metadata[i][0] != NULL; ++i) {
923 size_t const key_len = strlen(metadata[i][0]);
924 size_t const val_len = strlen(metadata[i][1]);
925
926 ceph_encode_32(&p, key_len);
927 memcpy(p, metadata[i][0], key_len);
928 p += key_len;
929 ceph_encode_32(&p, val_len);
930 memcpy(p, metadata[i][1], val_len);
931 p += val_len;
932 }
933
934 return msg;
935 }
936
937 /*
938 * send session open request.
939 *
940 * called under mdsc->mutex
941 */
942 static int __open_session(struct ceph_mds_client *mdsc,
943 struct ceph_mds_session *session)
944 {
945 struct ceph_msg *msg;
946 int mstate;
947 int mds = session->s_mds;
948
949 /* wait for mds to go active? */
950 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
951 dout("open_session to mds%d (%s)\n", mds,
952 ceph_mds_state_name(mstate));
953 session->s_state = CEPH_MDS_SESSION_OPENING;
954 session->s_renew_requested = jiffies;
955
956 /* send connect message */
957 msg = create_session_open_msg(mdsc, session->s_seq);
958 if (!msg)
959 return -ENOMEM;
960 ceph_con_send(&session->s_con, msg);
961 return 0;
962 }
963
964 /*
965 * open sessions for any export targets for the given mds
966 *
967 * called under mdsc->mutex
968 */
969 static struct ceph_mds_session *
970 __open_export_target_session(struct ceph_mds_client *mdsc, int target)
971 {
972 struct ceph_mds_session *session;
973
974 session = __ceph_lookup_mds_session(mdsc, target);
975 if (!session) {
976 session = register_session(mdsc, target);
977 if (IS_ERR(session))
978 return session;
979 }
980 if (session->s_state == CEPH_MDS_SESSION_NEW ||
981 session->s_state == CEPH_MDS_SESSION_CLOSING)
982 __open_session(mdsc, session);
983
984 return session;
985 }
986
987 struct ceph_mds_session *
988 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target)
989 {
990 struct ceph_mds_session *session;
991
992 dout("open_export_target_session to mds%d\n", target);
993
994 mutex_lock(&mdsc->mutex);
995 session = __open_export_target_session(mdsc, target);
996 mutex_unlock(&mdsc->mutex);
997
998 return session;
999 }
1000
1001 static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
1002 struct ceph_mds_session *session)
1003 {
1004 struct ceph_mds_info *mi;
1005 struct ceph_mds_session *ts;
1006 int i, mds = session->s_mds;
1007
1008 if (mds >= mdsc->mdsmap->m_num_mds)
1009 return;
1010
1011 mi = &mdsc->mdsmap->m_info[mds];
1012 dout("open_export_target_sessions for mds%d (%d targets)\n",
1013 session->s_mds, mi->num_export_targets);
1014
1015 for (i = 0; i < mi->num_export_targets; i++) {
1016 ts = __open_export_target_session(mdsc, mi->export_targets[i]);
1017 if (!IS_ERR(ts))
1018 ceph_put_mds_session(ts);
1019 }
1020 }
1021
1022 void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
1023 struct ceph_mds_session *session)
1024 {
1025 mutex_lock(&mdsc->mutex);
1026 __open_export_target_sessions(mdsc, session);
1027 mutex_unlock(&mdsc->mutex);
1028 }
1029
1030 /*
1031 * session caps
1032 */
1033
1034 /* caller holds s_cap_lock, we drop it */
1035 static void cleanup_cap_releases(struct ceph_mds_client *mdsc,
1036 struct ceph_mds_session *session)
1037 __releases(session->s_cap_lock)
1038 {
1039 LIST_HEAD(tmp_list);
1040 list_splice_init(&session->s_cap_releases, &tmp_list);
1041 session->s_num_cap_releases = 0;
1042 spin_unlock(&session->s_cap_lock);
1043
1044 dout("cleanup_cap_releases mds%d\n", session->s_mds);
1045 while (!list_empty(&tmp_list)) {
1046 struct ceph_cap *cap;
1047 /* zero out the in-progress message */
1048 cap = list_first_entry(&tmp_list,
1049 struct ceph_cap, session_caps);
1050 list_del(&cap->session_caps);
1051 ceph_put_cap(mdsc, cap);
1052 }
1053 }
1054
1055 static void cleanup_session_requests(struct ceph_mds_client *mdsc,
1056 struct ceph_mds_session *session)
1057 {
1058 struct ceph_mds_request *req;
1059 struct rb_node *p;
1060
1061 dout("cleanup_session_requests mds%d\n", session->s_mds);
1062 mutex_lock(&mdsc->mutex);
1063 while (!list_empty(&session->s_unsafe)) {
1064 req = list_first_entry(&session->s_unsafe,
1065 struct ceph_mds_request, r_unsafe_item);
1066 pr_warn_ratelimited(" dropping unsafe request %llu\n",
1067 req->r_tid);
1068 __unregister_request(mdsc, req);
1069 }
1070 /* zero r_attempts, so kick_requests() will re-send requests */
1071 p = rb_first(&mdsc->request_tree);
1072 while (p) {
1073 req = rb_entry(p, struct ceph_mds_request, r_node);
1074 p = rb_next(p);
1075 if (req->r_session &&
1076 req->r_session->s_mds == session->s_mds)
1077 req->r_attempts = 0;
1078 }
1079 mutex_unlock(&mdsc->mutex);
1080 }
1081
1082 /*
1083 * Helper to safely iterate over all caps associated with a session, with
1084 * special care taken to handle a racing __ceph_remove_cap().
1085 *
1086 * Caller must hold session s_mutex.
1087 */
1088 static int iterate_session_caps(struct ceph_mds_session *session,
1089 int (*cb)(struct inode *, struct ceph_cap *,
1090 void *), void *arg)
1091 {
1092 struct list_head *p;
1093 struct ceph_cap *cap;
1094 struct inode *inode, *last_inode = NULL;
1095 struct ceph_cap *old_cap = NULL;
1096 int ret;
1097
1098 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
1099 spin_lock(&session->s_cap_lock);
1100 p = session->s_caps.next;
1101 while (p != &session->s_caps) {
1102 cap = list_entry(p, struct ceph_cap, session_caps);
1103 inode = igrab(&cap->ci->vfs_inode);
1104 if (!inode) {
1105 p = p->next;
1106 continue;
1107 }
1108 session->s_cap_iterator = cap;
1109 spin_unlock(&session->s_cap_lock);
1110
1111 if (last_inode) {
1112 iput(last_inode);
1113 last_inode = NULL;
1114 }
1115 if (old_cap) {
1116 ceph_put_cap(session->s_mdsc, old_cap);
1117 old_cap = NULL;
1118 }
1119
1120 ret = cb(inode, cap, arg);
1121 last_inode = inode;
1122
1123 spin_lock(&session->s_cap_lock);
1124 p = p->next;
1125 if (cap->ci == NULL) {
1126 dout("iterate_session_caps finishing cap %p removal\n",
1127 cap);
1128 BUG_ON(cap->session != session);
1129 cap->session = NULL;
1130 list_del_init(&cap->session_caps);
1131 session->s_nr_caps--;
1132 if (cap->queue_release) {
1133 list_add_tail(&cap->session_caps,
1134 &session->s_cap_releases);
1135 session->s_num_cap_releases++;
1136 } else {
1137 old_cap = cap; /* put_cap it w/o locks held */
1138 }
1139 }
1140 if (ret < 0)
1141 goto out;
1142 }
1143 ret = 0;
1144 out:
1145 session->s_cap_iterator = NULL;
1146 spin_unlock(&session->s_cap_lock);
1147
1148 iput(last_inode);
1149 if (old_cap)
1150 ceph_put_cap(session->s_mdsc, old_cap);
1151
1152 return ret;
1153 }
1154
1155 static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
1156 void *arg)
1157 {
1158 struct ceph_fs_client *fsc = (struct ceph_fs_client *)arg;
1159 struct ceph_inode_info *ci = ceph_inode(inode);
1160 LIST_HEAD(to_remove);
1161 bool drop = false;
1162 bool invalidate = false;
1163
1164 dout("removing cap %p, ci is %p, inode is %p\n",
1165 cap, ci, &ci->vfs_inode);
1166 spin_lock(&ci->i_ceph_lock);
1167 __ceph_remove_cap(cap, false);
1168 if (!ci->i_auth_cap) {
1169 struct ceph_cap_flush *cf;
1170 struct ceph_mds_client *mdsc = fsc->mdsc;
1171
1172 ci->i_ceph_flags |= CEPH_I_CAP_DROPPED;
1173
1174 if (ci->i_wrbuffer_ref > 0 &&
1175 READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN)
1176 invalidate = true;
1177
1178 while (!list_empty(&ci->i_cap_flush_list)) {
1179 cf = list_first_entry(&ci->i_cap_flush_list,
1180 struct ceph_cap_flush, i_list);
1181 list_move(&cf->i_list, &to_remove);
1182 }
1183
1184 spin_lock(&mdsc->cap_dirty_lock);
1185
1186 list_for_each_entry(cf, &to_remove, i_list)
1187 list_del(&cf->g_list);
1188
1189 if (!list_empty(&ci->i_dirty_item)) {
1190 pr_warn_ratelimited(
1191 " dropping dirty %s state for %p %lld\n",
1192 ceph_cap_string(ci->i_dirty_caps),
1193 inode, ceph_ino(inode));
1194 ci->i_dirty_caps = 0;
1195 list_del_init(&ci->i_dirty_item);
1196 drop = true;
1197 }
1198 if (!list_empty(&ci->i_flushing_item)) {
1199 pr_warn_ratelimited(
1200 " dropping dirty+flushing %s state for %p %lld\n",
1201 ceph_cap_string(ci->i_flushing_caps),
1202 inode, ceph_ino(inode));
1203 ci->i_flushing_caps = 0;
1204 list_del_init(&ci->i_flushing_item);
1205 mdsc->num_cap_flushing--;
1206 drop = true;
1207 }
1208 spin_unlock(&mdsc->cap_dirty_lock);
1209
1210 if (!ci->i_dirty_caps && ci->i_prealloc_cap_flush) {
1211 list_add(&ci->i_prealloc_cap_flush->i_list, &to_remove);
1212 ci->i_prealloc_cap_flush = NULL;
1213 }
1214 }
1215 spin_unlock(&ci->i_ceph_lock);
1216 while (!list_empty(&to_remove)) {
1217 struct ceph_cap_flush *cf;
1218 cf = list_first_entry(&to_remove,
1219 struct ceph_cap_flush, i_list);
1220 list_del(&cf->i_list);
1221 ceph_free_cap_flush(cf);
1222 }
1223
1224 wake_up_all(&ci->i_cap_wq);
1225 if (invalidate)
1226 ceph_queue_invalidate(inode);
1227 if (drop)
1228 iput(inode);
1229 return 0;
1230 }
1231
1232 /*
1233 * caller must hold session s_mutex
1234 */
1235 static void remove_session_caps(struct ceph_mds_session *session)
1236 {
1237 struct ceph_fs_client *fsc = session->s_mdsc->fsc;
1238 struct super_block *sb = fsc->sb;
1239 dout("remove_session_caps on %p\n", session);
1240 iterate_session_caps(session, remove_session_caps_cb, fsc);
1241
1242 wake_up_all(&fsc->mdsc->cap_flushing_wq);
1243
1244 spin_lock(&session->s_cap_lock);
1245 if (session->s_nr_caps > 0) {
1246 struct inode *inode;
1247 struct ceph_cap *cap, *prev = NULL;
1248 struct ceph_vino vino;
1249 /*
1250 * iterate_session_caps() skips inodes that are being
1251 * deleted, we need to wait until deletions are complete.
1252 * __wait_on_freeing_inode() is designed for the job,
1253 * but it is not exported, so use lookup inode function
1254 * to access it.
1255 */
1256 while (!list_empty(&session->s_caps)) {
1257 cap = list_entry(session->s_caps.next,
1258 struct ceph_cap, session_caps);
1259 if (cap == prev)
1260 break;
1261 prev = cap;
1262 vino = cap->ci->i_vino;
1263 spin_unlock(&session->s_cap_lock);
1264
1265 inode = ceph_find_inode(sb, vino);
1266 iput(inode);
1267
1268 spin_lock(&session->s_cap_lock);
1269 }
1270 }
1271
1272 // drop cap expires and unlock s_cap_lock
1273 cleanup_cap_releases(session->s_mdsc, session);
1274
1275 BUG_ON(session->s_nr_caps > 0);
1276 BUG_ON(!list_empty(&session->s_cap_flushing));
1277 }
1278
1279 /*
1280 * wake up any threads waiting on this session's caps. if the cap is
1281 * old (didn't get renewed on the client reconnect), remove it now.
1282 *
1283 * caller must hold s_mutex.
1284 */
1285 static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
1286 void *arg)
1287 {
1288 struct ceph_inode_info *ci = ceph_inode(inode);
1289
1290 if (arg) {
1291 spin_lock(&ci->i_ceph_lock);
1292 ci->i_wanted_max_size = 0;
1293 ci->i_requested_max_size = 0;
1294 spin_unlock(&ci->i_ceph_lock);
1295 }
1296 wake_up_all(&ci->i_cap_wq);
1297 return 0;
1298 }
1299
1300 static void wake_up_session_caps(struct ceph_mds_session *session,
1301 int reconnect)
1302 {
1303 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
1304 iterate_session_caps(session, wake_up_session_cb,
1305 (void *)(unsigned long)reconnect);
1306 }
1307
1308 /*
1309 * Send periodic message to MDS renewing all currently held caps. The
1310 * ack will reset the expiration for all caps from this session.
1311 *
1312 * caller holds s_mutex
1313 */
1314 static int send_renew_caps(struct ceph_mds_client *mdsc,
1315 struct ceph_mds_session *session)
1316 {
1317 struct ceph_msg *msg;
1318 int state;
1319
1320 if (time_after_eq(jiffies, session->s_cap_ttl) &&
1321 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
1322 pr_info("mds%d caps stale\n", session->s_mds);
1323 session->s_renew_requested = jiffies;
1324
1325 /* do not try to renew caps until a recovering mds has reconnected
1326 * with its clients. */
1327 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
1328 if (state < CEPH_MDS_STATE_RECONNECT) {
1329 dout("send_renew_caps ignoring mds%d (%s)\n",
1330 session->s_mds, ceph_mds_state_name(state));
1331 return 0;
1332 }
1333
1334 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
1335 ceph_mds_state_name(state));
1336 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
1337 ++session->s_renew_seq);
1338 if (!msg)
1339 return -ENOMEM;
1340 ceph_con_send(&session->s_con, msg);
1341 return 0;
1342 }
1343
1344 static int send_flushmsg_ack(struct ceph_mds_client *mdsc,
1345 struct ceph_mds_session *session, u64 seq)
1346 {
1347 struct ceph_msg *msg;
1348
1349 dout("send_flushmsg_ack to mds%d (%s)s seq %lld\n",
1350 session->s_mds, ceph_session_state_name(session->s_state), seq);
1351 msg = create_session_msg(CEPH_SESSION_FLUSHMSG_ACK, seq);
1352 if (!msg)
1353 return -ENOMEM;
1354 ceph_con_send(&session->s_con, msg);
1355 return 0;
1356 }
1357
1358
1359 /*
1360 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
1361 *
1362 * Called under session->s_mutex
1363 */
1364 static void renewed_caps(struct ceph_mds_client *mdsc,
1365 struct ceph_mds_session *session, int is_renew)
1366 {
1367 int was_stale;
1368 int wake = 0;
1369
1370 spin_lock(&session->s_cap_lock);
1371 was_stale = is_renew && time_after_eq(jiffies, session->s_cap_ttl);
1372
1373 session->s_cap_ttl = session->s_renew_requested +
1374 mdsc->mdsmap->m_session_timeout*HZ;
1375
1376 if (was_stale) {
1377 if (time_before(jiffies, session->s_cap_ttl)) {
1378 pr_info("mds%d caps renewed\n", session->s_mds);
1379 wake = 1;
1380 } else {
1381 pr_info("mds%d caps still stale\n", session->s_mds);
1382 }
1383 }
1384 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
1385 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
1386 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
1387 spin_unlock(&session->s_cap_lock);
1388
1389 if (wake)
1390 wake_up_session_caps(session, 0);
1391 }
1392
1393 /*
1394 * send a session close request
1395 */
1396 static int request_close_session(struct ceph_mds_client *mdsc,
1397 struct ceph_mds_session *session)
1398 {
1399 struct ceph_msg *msg;
1400
1401 dout("request_close_session mds%d state %s seq %lld\n",
1402 session->s_mds, ceph_session_state_name(session->s_state),
1403 session->s_seq);
1404 msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
1405 if (!msg)
1406 return -ENOMEM;
1407 ceph_con_send(&session->s_con, msg);
1408 return 1;
1409 }
1410
1411 /*
1412 * Called with s_mutex held.
1413 */
1414 static int __close_session(struct ceph_mds_client *mdsc,
1415 struct ceph_mds_session *session)
1416 {
1417 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
1418 return 0;
1419 session->s_state = CEPH_MDS_SESSION_CLOSING;
1420 return request_close_session(mdsc, session);
1421 }
1422
1423 /*
1424 * Trim old(er) caps.
1425 *
1426 * Because we can't cache an inode without one or more caps, we do
1427 * this indirectly: if a cap is unused, we prune its aliases, at which
1428 * point the inode will hopefully get dropped to.
1429 *
1430 * Yes, this is a bit sloppy. Our only real goal here is to respond to
1431 * memory pressure from the MDS, though, so it needn't be perfect.
1432 */
1433 static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
1434 {
1435 struct ceph_mds_session *session = arg;
1436 struct ceph_inode_info *ci = ceph_inode(inode);
1437 int used, wanted, oissued, mine;
1438
1439 if (session->s_trim_caps <= 0)
1440 return -1;
1441
1442 spin_lock(&ci->i_ceph_lock);
1443 mine = cap->issued | cap->implemented;
1444 used = __ceph_caps_used(ci);
1445 wanted = __ceph_caps_file_wanted(ci);
1446 oissued = __ceph_caps_issued_other(ci, cap);
1447
1448 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s wanted %s\n",
1449 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
1450 ceph_cap_string(used), ceph_cap_string(wanted));
1451 if (cap == ci->i_auth_cap) {
1452 if (ci->i_dirty_caps || ci->i_flushing_caps ||
1453 !list_empty(&ci->i_cap_snaps))
1454 goto out;
1455 if ((used | wanted) & CEPH_CAP_ANY_WR)
1456 goto out;
1457 }
1458 /* The inode has cached pages, but it's no longer used.
1459 * we can safely drop it */
1460 if (wanted == 0 && used == CEPH_CAP_FILE_CACHE &&
1461 !(oissued & CEPH_CAP_FILE_CACHE)) {
1462 used = 0;
1463 oissued = 0;
1464 }
1465 if ((used | wanted) & ~oissued & mine)
1466 goto out; /* we need these caps */
1467
1468 session->s_trim_caps--;
1469 if (oissued) {
1470 /* we aren't the only cap.. just remove us */
1471 __ceph_remove_cap(cap, true);
1472 } else {
1473 /* try dropping referring dentries */
1474 spin_unlock(&ci->i_ceph_lock);
1475 d_prune_aliases(inode);
1476 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
1477 inode, cap, atomic_read(&inode->i_count));
1478 return 0;
1479 }
1480
1481 out:
1482 spin_unlock(&ci->i_ceph_lock);
1483 return 0;
1484 }
1485
1486 /*
1487 * Trim session cap count down to some max number.
1488 */
1489 static int trim_caps(struct ceph_mds_client *mdsc,
1490 struct ceph_mds_session *session,
1491 int max_caps)
1492 {
1493 int trim_caps = session->s_nr_caps - max_caps;
1494
1495 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1496 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1497 if (trim_caps > 0) {
1498 session->s_trim_caps = trim_caps;
1499 iterate_session_caps(session, trim_caps_cb, session);
1500 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1501 session->s_mds, session->s_nr_caps, max_caps,
1502 trim_caps - session->s_trim_caps);
1503 session->s_trim_caps = 0;
1504 }
1505
1506 ceph_send_cap_releases(mdsc, session);
1507 return 0;
1508 }
1509
1510 static int check_caps_flush(struct ceph_mds_client *mdsc,
1511 u64 want_flush_tid)
1512 {
1513 int ret = 1;
1514
1515 spin_lock(&mdsc->cap_dirty_lock);
1516 if (!list_empty(&mdsc->cap_flush_list)) {
1517 struct ceph_cap_flush *cf =
1518 list_first_entry(&mdsc->cap_flush_list,
1519 struct ceph_cap_flush, g_list);
1520 if (cf->tid <= want_flush_tid) {
1521 dout("check_caps_flush still flushing tid "
1522 "%llu <= %llu\n", cf->tid, want_flush_tid);
1523 ret = 0;
1524 }
1525 }
1526 spin_unlock(&mdsc->cap_dirty_lock);
1527 return ret;
1528 }
1529
1530 /*
1531 * flush all dirty inode data to disk.
1532 *
1533 * returns true if we've flushed through want_flush_tid
1534 */
1535 static void wait_caps_flush(struct ceph_mds_client *mdsc,
1536 u64 want_flush_tid)
1537 {
1538 dout("check_caps_flush want %llu\n", want_flush_tid);
1539
1540 wait_event(mdsc->cap_flushing_wq,
1541 check_caps_flush(mdsc, want_flush_tid));
1542
1543 dout("check_caps_flush ok, flushed thru %llu\n", want_flush_tid);
1544 }
1545
1546 /*
1547 * called under s_mutex
1548 */
1549 void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
1550 struct ceph_mds_session *session)
1551 {
1552 struct ceph_msg *msg = NULL;
1553 struct ceph_mds_cap_release *head;
1554 struct ceph_mds_cap_item *item;
1555 struct ceph_osd_client *osdc = &mdsc->fsc->client->osdc;
1556 struct ceph_cap *cap;
1557 LIST_HEAD(tmp_list);
1558 int num_cap_releases;
1559 __le32 barrier, *cap_barrier;
1560
1561 down_read(&osdc->lock);
1562 barrier = cpu_to_le32(osdc->epoch_barrier);
1563 up_read(&osdc->lock);
1564
1565 spin_lock(&session->s_cap_lock);
1566 again:
1567 list_splice_init(&session->s_cap_releases, &tmp_list);
1568 num_cap_releases = session->s_num_cap_releases;
1569 session->s_num_cap_releases = 0;
1570 spin_unlock(&session->s_cap_lock);
1571
1572 while (!list_empty(&tmp_list)) {
1573 if (!msg) {
1574 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE,
1575 PAGE_SIZE, GFP_NOFS, false);
1576 if (!msg)
1577 goto out_err;
1578 head = msg->front.iov_base;
1579 head->num = cpu_to_le32(0);
1580 msg->front.iov_len = sizeof(*head);
1581
1582 msg->hdr.version = cpu_to_le16(2);
1583 msg->hdr.compat_version = cpu_to_le16(1);
1584 }
1585
1586 cap = list_first_entry(&tmp_list, struct ceph_cap,
1587 session_caps);
1588 list_del(&cap->session_caps);
1589 num_cap_releases--;
1590
1591 head = msg->front.iov_base;
1592 le32_add_cpu(&head->num, 1);
1593 item = msg->front.iov_base + msg->front.iov_len;
1594 item->ino = cpu_to_le64(cap->cap_ino);
1595 item->cap_id = cpu_to_le64(cap->cap_id);
1596 item->migrate_seq = cpu_to_le32(cap->mseq);
1597 item->seq = cpu_to_le32(cap->issue_seq);
1598 msg->front.iov_len += sizeof(*item);
1599
1600 ceph_put_cap(mdsc, cap);
1601
1602 if (le32_to_cpu(head->num) == CEPH_CAPS_PER_RELEASE) {
1603 // Append cap_barrier field
1604 cap_barrier = msg->front.iov_base + msg->front.iov_len;
1605 *cap_barrier = barrier;
1606 msg->front.iov_len += sizeof(*cap_barrier);
1607
1608 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1609 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1610 ceph_con_send(&session->s_con, msg);
1611 msg = NULL;
1612 }
1613 }
1614
1615 BUG_ON(num_cap_releases != 0);
1616
1617 spin_lock(&session->s_cap_lock);
1618 if (!list_empty(&session->s_cap_releases))
1619 goto again;
1620 spin_unlock(&session->s_cap_lock);
1621
1622 if (msg) {
1623 // Append cap_barrier field
1624 cap_barrier = msg->front.iov_base + msg->front.iov_len;
1625 *cap_barrier = barrier;
1626 msg->front.iov_len += sizeof(*cap_barrier);
1627
1628 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1629 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1630 ceph_con_send(&session->s_con, msg);
1631 }
1632 return;
1633 out_err:
1634 pr_err("send_cap_releases mds%d, failed to allocate message\n",
1635 session->s_mds);
1636 spin_lock(&session->s_cap_lock);
1637 list_splice(&tmp_list, &session->s_cap_releases);
1638 session->s_num_cap_releases += num_cap_releases;
1639 spin_unlock(&session->s_cap_lock);
1640 }
1641
1642 /*
1643 * requests
1644 */
1645
1646 int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
1647 struct inode *dir)
1648 {
1649 struct ceph_inode_info *ci = ceph_inode(dir);
1650 struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1651 struct ceph_mount_options *opt = req->r_mdsc->fsc->mount_options;
1652 size_t size = sizeof(struct ceph_mds_reply_dir_entry);
1653 int order, num_entries;
1654
1655 spin_lock(&ci->i_ceph_lock);
1656 num_entries = ci->i_files + ci->i_subdirs;
1657 spin_unlock(&ci->i_ceph_lock);
1658 num_entries = max(num_entries, 1);
1659 num_entries = min(num_entries, opt->max_readdir);
1660
1661 order = get_order(size * num_entries);
1662 while (order >= 0) {
1663 rinfo->dir_entries = (void*)__get_free_pages(GFP_KERNEL |
1664 __GFP_NOWARN,
1665 order);
1666 if (rinfo->dir_entries)
1667 break;
1668 order--;
1669 }
1670 if (!rinfo->dir_entries)
1671 return -ENOMEM;
1672
1673 num_entries = (PAGE_SIZE << order) / size;
1674 num_entries = min(num_entries, opt->max_readdir);
1675
1676 rinfo->dir_buf_size = PAGE_SIZE << order;
1677 req->r_num_caps = num_entries + 1;
1678 req->r_args.readdir.max_entries = cpu_to_le32(num_entries);
1679 req->r_args.readdir.max_bytes = cpu_to_le32(opt->max_readdir_bytes);
1680 return 0;
1681 }
1682
1683 /*
1684 * Create an mds request.
1685 */
1686 struct ceph_mds_request *
1687 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1688 {
1689 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1690 struct timespec ts;
1691
1692 if (!req)
1693 return ERR_PTR(-ENOMEM);
1694
1695 mutex_init(&req->r_fill_mutex);
1696 req->r_mdsc = mdsc;
1697 req->r_started = jiffies;
1698 req->r_resend_mds = -1;
1699 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1700 INIT_LIST_HEAD(&req->r_unsafe_target_item);
1701 req->r_fmode = -1;
1702 kref_init(&req->r_kref);
1703 RB_CLEAR_NODE(&req->r_node);
1704 INIT_LIST_HEAD(&req->r_wait);
1705 init_completion(&req->r_completion);
1706 init_completion(&req->r_safe_completion);
1707 INIT_LIST_HEAD(&req->r_unsafe_item);
1708
1709 ktime_get_real_ts(&ts);
1710 req->r_stamp = timespec_trunc(ts, mdsc->fsc->sb->s_time_gran);
1711
1712 req->r_op = op;
1713 req->r_direct_mode = mode;
1714 return req;
1715 }
1716
1717 /*
1718 * return oldest (lowest) request, tid in request tree, 0 if none.
1719 *
1720 * called under mdsc->mutex.
1721 */
1722 static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1723 {
1724 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1725 return NULL;
1726 return rb_entry(rb_first(&mdsc->request_tree),
1727 struct ceph_mds_request, r_node);
1728 }
1729
1730 static inline u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1731 {
1732 return mdsc->oldest_tid;
1733 }
1734
1735 /*
1736 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1737 * on build_path_from_dentry in fs/cifs/dir.c.
1738 *
1739 * If @stop_on_nosnap, generate path relative to the first non-snapped
1740 * inode.
1741 *
1742 * Encode hidden .snap dirs as a double /, i.e.
1743 * foo/.snap/bar -> foo//bar
1744 */
1745 char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1746 int stop_on_nosnap)
1747 {
1748 struct dentry *temp;
1749 char *path;
1750 int len, pos;
1751 unsigned seq;
1752
1753 if (dentry == NULL)
1754 return ERR_PTR(-EINVAL);
1755
1756 retry:
1757 len = 0;
1758 seq = read_seqbegin(&rename_lock);
1759 rcu_read_lock();
1760 for (temp = dentry; !IS_ROOT(temp);) {
1761 struct inode *inode = d_inode(temp);
1762 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1763 len++; /* slash only */
1764 else if (stop_on_nosnap && inode &&
1765 ceph_snap(inode) == CEPH_NOSNAP)
1766 break;
1767 else
1768 len += 1 + temp->d_name.len;
1769 temp = temp->d_parent;
1770 }
1771 rcu_read_unlock();
1772 if (len)
1773 len--; /* no leading '/' */
1774
1775 path = kmalloc(len+1, GFP_NOFS);
1776 if (path == NULL)
1777 return ERR_PTR(-ENOMEM);
1778 pos = len;
1779 path[pos] = 0; /* trailing null */
1780 rcu_read_lock();
1781 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1782 struct inode *inode;
1783
1784 spin_lock(&temp->d_lock);
1785 inode = d_inode(temp);
1786 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1787 dout("build_path path+%d: %p SNAPDIR\n",
1788 pos, temp);
1789 } else if (stop_on_nosnap && inode &&
1790 ceph_snap(inode) == CEPH_NOSNAP) {
1791 spin_unlock(&temp->d_lock);
1792 break;
1793 } else {
1794 pos -= temp->d_name.len;
1795 if (pos < 0) {
1796 spin_unlock(&temp->d_lock);
1797 break;
1798 }
1799 strncpy(path + pos, temp->d_name.name,
1800 temp->d_name.len);
1801 }
1802 spin_unlock(&temp->d_lock);
1803 if (pos)
1804 path[--pos] = '/';
1805 temp = temp->d_parent;
1806 }
1807 rcu_read_unlock();
1808 if (pos != 0 || read_seqretry(&rename_lock, seq)) {
1809 pr_err("build_path did not end path lookup where "
1810 "expected, namelen is %d, pos is %d\n", len, pos);
1811 /* presumably this is only possible if racing with a
1812 rename of one of the parent directories (we can not
1813 lock the dentries above us to prevent this, but
1814 retrying should be harmless) */
1815 kfree(path);
1816 goto retry;
1817 }
1818
1819 *base = ceph_ino(d_inode(temp));
1820 *plen = len;
1821 dout("build_path on %p %d built %llx '%.*s'\n",
1822 dentry, d_count(dentry), *base, len, path);
1823 return path;
1824 }
1825
1826 static int build_dentry_path(struct dentry *dentry, struct inode *dir,
1827 const char **ppath, int *ppathlen, u64 *pino,
1828 int *pfreepath)
1829 {
1830 char *path;
1831
1832 rcu_read_lock();
1833 if (!dir)
1834 dir = d_inode_rcu(dentry->d_parent);
1835 if (dir && ceph_snap(dir) == CEPH_NOSNAP) {
1836 *pino = ceph_ino(dir);
1837 rcu_read_unlock();
1838 *ppath = dentry->d_name.name;
1839 *ppathlen = dentry->d_name.len;
1840 return 0;
1841 }
1842 rcu_read_unlock();
1843 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1844 if (IS_ERR(path))
1845 return PTR_ERR(path);
1846 *ppath = path;
1847 *pfreepath = 1;
1848 return 0;
1849 }
1850
1851 static int build_inode_path(struct inode *inode,
1852 const char **ppath, int *ppathlen, u64 *pino,
1853 int *pfreepath)
1854 {
1855 struct dentry *dentry;
1856 char *path;
1857
1858 if (ceph_snap(inode) == CEPH_NOSNAP) {
1859 *pino = ceph_ino(inode);
1860 *ppathlen = 0;
1861 return 0;
1862 }
1863 dentry = d_find_alias(inode);
1864 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1865 dput(dentry);
1866 if (IS_ERR(path))
1867 return PTR_ERR(path);
1868 *ppath = path;
1869 *pfreepath = 1;
1870 return 0;
1871 }
1872
1873 /*
1874 * request arguments may be specified via an inode *, a dentry *, or
1875 * an explicit ino+path.
1876 */
1877 static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1878 struct inode *rdiri, const char *rpath,
1879 u64 rino, const char **ppath, int *pathlen,
1880 u64 *ino, int *freepath)
1881 {
1882 int r = 0;
1883
1884 if (rinode) {
1885 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1886 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1887 ceph_snap(rinode));
1888 } else if (rdentry) {
1889 r = build_dentry_path(rdentry, rdiri, ppath, pathlen, ino,
1890 freepath);
1891 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1892 *ppath);
1893 } else if (rpath || rino) {
1894 *ino = rino;
1895 *ppath = rpath;
1896 *pathlen = rpath ? strlen(rpath) : 0;
1897 dout(" path %.*s\n", *pathlen, rpath);
1898 }
1899
1900 return r;
1901 }
1902
1903 /*
1904 * called under mdsc->mutex
1905 */
1906 static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1907 struct ceph_mds_request *req,
1908 int mds, bool drop_cap_releases)
1909 {
1910 struct ceph_msg *msg;
1911 struct ceph_mds_request_head *head;
1912 const char *path1 = NULL;
1913 const char *path2 = NULL;
1914 u64 ino1 = 0, ino2 = 0;
1915 int pathlen1 = 0, pathlen2 = 0;
1916 int freepath1 = 0, freepath2 = 0;
1917 int len;
1918 u16 releases;
1919 void *p, *end;
1920 int ret;
1921
1922 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1923 req->r_parent, req->r_path1, req->r_ino1.ino,
1924 &path1, &pathlen1, &ino1, &freepath1);
1925 if (ret < 0) {
1926 msg = ERR_PTR(ret);
1927 goto out;
1928 }
1929
1930 ret = set_request_path_attr(NULL, req->r_old_dentry,
1931 req->r_old_dentry_dir,
1932 req->r_path2, req->r_ino2.ino,
1933 &path2, &pathlen2, &ino2, &freepath2);
1934 if (ret < 0) {
1935 msg = ERR_PTR(ret);
1936 goto out_free1;
1937 }
1938
1939 len = sizeof(*head) +
1940 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64)) +
1941 sizeof(struct ceph_timespec);
1942
1943 /* calculate (max) length for cap releases */
1944 len += sizeof(struct ceph_mds_request_release) *
1945 (!!req->r_inode_drop + !!req->r_dentry_drop +
1946 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1947 if (req->r_dentry_drop)
1948 len += req->r_dentry->d_name.len;
1949 if (req->r_old_dentry_drop)
1950 len += req->r_old_dentry->d_name.len;
1951
1952 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS, false);
1953 if (!msg) {
1954 msg = ERR_PTR(-ENOMEM);
1955 goto out_free2;
1956 }
1957
1958 msg->hdr.version = cpu_to_le16(2);
1959 msg->hdr.tid = cpu_to_le64(req->r_tid);
1960
1961 head = msg->front.iov_base;
1962 p = msg->front.iov_base + sizeof(*head);
1963 end = msg->front.iov_base + msg->front.iov_len;
1964
1965 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1966 head->op = cpu_to_le32(req->r_op);
1967 head->caller_uid = cpu_to_le32(from_kuid(&init_user_ns, req->r_uid));
1968 head->caller_gid = cpu_to_le32(from_kgid(&init_user_ns, req->r_gid));
1969 head->args = req->r_args;
1970
1971 ceph_encode_filepath(&p, end, ino1, path1);
1972 ceph_encode_filepath(&p, end, ino2, path2);
1973
1974 /* make note of release offset, in case we need to replay */
1975 req->r_request_release_offset = p - msg->front.iov_base;
1976
1977 /* cap releases */
1978 releases = 0;
1979 if (req->r_inode_drop)
1980 releases += ceph_encode_inode_release(&p,
1981 req->r_inode ? req->r_inode : d_inode(req->r_dentry),
1982 mds, req->r_inode_drop, req->r_inode_unless, 0);
1983 if (req->r_dentry_drop)
1984 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1985 req->r_parent, mds, req->r_dentry_drop,
1986 req->r_dentry_unless);
1987 if (req->r_old_dentry_drop)
1988 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1989 req->r_old_dentry_dir, mds,
1990 req->r_old_dentry_drop,
1991 req->r_old_dentry_unless);
1992 if (req->r_old_inode_drop)
1993 releases += ceph_encode_inode_release(&p,
1994 d_inode(req->r_old_dentry),
1995 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1996
1997 if (drop_cap_releases) {
1998 releases = 0;
1999 p = msg->front.iov_base + req->r_request_release_offset;
2000 }
2001
2002 head->num_releases = cpu_to_le16(releases);
2003
2004 /* time stamp */
2005 {
2006 struct ceph_timespec ts;
2007 ceph_encode_timespec(&ts, &req->r_stamp);
2008 ceph_encode_copy(&p, &ts, sizeof(ts));
2009 }
2010
2011 BUG_ON(p > end);
2012 msg->front.iov_len = p - msg->front.iov_base;
2013 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
2014
2015 if (req->r_pagelist) {
2016 struct ceph_pagelist *pagelist = req->r_pagelist;
2017 refcount_inc(&pagelist->refcnt);
2018 ceph_msg_data_add_pagelist(msg, pagelist);
2019 msg->hdr.data_len = cpu_to_le32(pagelist->length);
2020 } else {
2021 msg->hdr.data_len = 0;
2022 }
2023
2024 msg->hdr.data_off = cpu_to_le16(0);
2025
2026 out_free2:
2027 if (freepath2)
2028 kfree((char *)path2);
2029 out_free1:
2030 if (freepath1)
2031 kfree((char *)path1);
2032 out:
2033 return msg;
2034 }
2035
2036 /*
2037 * called under mdsc->mutex if error, under no mutex if
2038 * success.
2039 */
2040 static void complete_request(struct ceph_mds_client *mdsc,
2041 struct ceph_mds_request *req)
2042 {
2043 if (req->r_callback)
2044 req->r_callback(mdsc, req);
2045 else
2046 complete_all(&req->r_completion);
2047 }
2048
2049 /*
2050 * called under mdsc->mutex
2051 */
2052 static int __prepare_send_request(struct ceph_mds_client *mdsc,
2053 struct ceph_mds_request *req,
2054 int mds, bool drop_cap_releases)
2055 {
2056 struct ceph_mds_request_head *rhead;
2057 struct ceph_msg *msg;
2058 int flags = 0;
2059
2060 req->r_attempts++;
2061 if (req->r_inode) {
2062 struct ceph_cap *cap =
2063 ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
2064
2065 if (cap)
2066 req->r_sent_on_mseq = cap->mseq;
2067 else
2068 req->r_sent_on_mseq = -1;
2069 }
2070 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
2071 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
2072
2073 if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
2074 void *p;
2075 /*
2076 * Replay. Do not regenerate message (and rebuild
2077 * paths, etc.); just use the original message.
2078 * Rebuilding paths will break for renames because
2079 * d_move mangles the src name.
2080 */
2081 msg = req->r_request;
2082 rhead = msg->front.iov_base;
2083
2084 flags = le32_to_cpu(rhead->flags);
2085 flags |= CEPH_MDS_FLAG_REPLAY;
2086 rhead->flags = cpu_to_le32(flags);
2087
2088 if (req->r_target_inode)
2089 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
2090
2091 rhead->num_retry = req->r_attempts - 1;
2092
2093 /* remove cap/dentry releases from message */
2094 rhead->num_releases = 0;
2095
2096 /* time stamp */
2097 p = msg->front.iov_base + req->r_request_release_offset;
2098 {
2099 struct ceph_timespec ts;
2100 ceph_encode_timespec(&ts, &req->r_stamp);
2101 ceph_encode_copy(&p, &ts, sizeof(ts));
2102 }
2103
2104 msg->front.iov_len = p - msg->front.iov_base;
2105 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
2106 return 0;
2107 }
2108
2109 if (req->r_request) {
2110 ceph_msg_put(req->r_request);
2111 req->r_request = NULL;
2112 }
2113 msg = create_request_message(mdsc, req, mds, drop_cap_releases);
2114 if (IS_ERR(msg)) {
2115 req->r_err = PTR_ERR(msg);
2116 return PTR_ERR(msg);
2117 }
2118 req->r_request = msg;
2119
2120 rhead = msg->front.iov_base;
2121 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
2122 if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
2123 flags |= CEPH_MDS_FLAG_REPLAY;
2124 if (req->r_parent)
2125 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
2126 rhead->flags = cpu_to_le32(flags);
2127 rhead->num_fwd = req->r_num_fwd;
2128 rhead->num_retry = req->r_attempts - 1;
2129 rhead->ino = 0;
2130
2131 dout(" r_parent = %p\n", req->r_parent);
2132 return 0;
2133 }
2134
2135 /*
2136 * send request, or put it on the appropriate wait list.
2137 */
2138 static int __do_request(struct ceph_mds_client *mdsc,
2139 struct ceph_mds_request *req)
2140 {
2141 struct ceph_mds_session *session = NULL;
2142 int mds = -1;
2143 int err = 0;
2144
2145 if (req->r_err || test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
2146 if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags))
2147 __unregister_request(mdsc, req);
2148 goto out;
2149 }
2150
2151 if (req->r_timeout &&
2152 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
2153 dout("do_request timed out\n");
2154 err = -EIO;
2155 goto finish;
2156 }
2157 if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
2158 dout("do_request forced umount\n");
2159 err = -EIO;
2160 goto finish;
2161 }
2162 if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_MOUNTING) {
2163 if (mdsc->mdsmap_err) {
2164 err = mdsc->mdsmap_err;
2165 dout("do_request mdsmap err %d\n", err);
2166 goto finish;
2167 }
2168 if (mdsc->mdsmap->m_epoch == 0) {
2169 dout("do_request no mdsmap, waiting for map\n");
2170 list_add(&req->r_wait, &mdsc->waiting_for_map);
2171 goto finish;
2172 }
2173 if (!(mdsc->fsc->mount_options->flags &
2174 CEPH_MOUNT_OPT_MOUNTWAIT) &&
2175 !ceph_mdsmap_is_cluster_available(mdsc->mdsmap)) {
2176 err = -ENOENT;
2177 pr_info("probably no mds server is up\n");
2178 goto finish;
2179 }
2180 }
2181
2182 put_request_session(req);
2183
2184 mds = __choose_mds(mdsc, req);
2185 if (mds < 0 ||
2186 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
2187 dout("do_request no mds or not active, waiting for map\n");
2188 list_add(&req->r_wait, &mdsc->waiting_for_map);
2189 goto out;
2190 }
2191
2192 /* get, open session */
2193 session = __ceph_lookup_mds_session(mdsc, mds);
2194 if (!session) {
2195 session = register_session(mdsc, mds);
2196 if (IS_ERR(session)) {
2197 err = PTR_ERR(session);
2198 goto finish;
2199 }
2200 }
2201 req->r_session = get_session(session);
2202
2203 dout("do_request mds%d session %p state %s\n", mds, session,
2204 ceph_session_state_name(session->s_state));
2205 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
2206 session->s_state != CEPH_MDS_SESSION_HUNG) {
2207 if (session->s_state == CEPH_MDS_SESSION_REJECTED) {
2208 err = -EACCES;
2209 goto out_session;
2210 }
2211 if (session->s_state == CEPH_MDS_SESSION_NEW ||
2212 session->s_state == CEPH_MDS_SESSION_CLOSING)
2213 __open_session(mdsc, session);
2214 list_add(&req->r_wait, &session->s_waiting);
2215 goto out_session;
2216 }
2217
2218 /* send request */
2219 req->r_resend_mds = -1; /* forget any previous mds hint */
2220
2221 if (req->r_request_started == 0) /* note request start time */
2222 req->r_request_started = jiffies;
2223
2224 err = __prepare_send_request(mdsc, req, mds, false);
2225 if (!err) {
2226 ceph_msg_get(req->r_request);
2227 ceph_con_send(&session->s_con, req->r_request);
2228 }
2229
2230 out_session:
2231 ceph_put_mds_session(session);
2232 finish:
2233 if (err) {
2234 dout("__do_request early error %d\n", err);
2235 req->r_err = err;
2236 complete_request(mdsc, req);
2237 __unregister_request(mdsc, req);
2238 }
2239 out:
2240 return err;
2241 }
2242
2243 /*
2244 * called under mdsc->mutex
2245 */
2246 static void __wake_requests(struct ceph_mds_client *mdsc,
2247 struct list_head *head)
2248 {
2249 struct ceph_mds_request *req;
2250 LIST_HEAD(tmp_list);
2251
2252 list_splice_init(head, &tmp_list);
2253
2254 while (!list_empty(&tmp_list)) {
2255 req = list_entry(tmp_list.next,
2256 struct ceph_mds_request, r_wait);
2257 list_del_init(&req->r_wait);
2258 dout(" wake request %p tid %llu\n", req, req->r_tid);
2259 __do_request(mdsc, req);
2260 }
2261 }
2262
2263 /*
2264 * Wake up threads with requests pending for @mds, so that they can
2265 * resubmit their requests to a possibly different mds.
2266 */
2267 static void kick_requests(struct ceph_mds_client *mdsc, int mds)
2268 {
2269 struct ceph_mds_request *req;
2270 struct rb_node *p = rb_first(&mdsc->request_tree);
2271
2272 dout("kick_requests mds%d\n", mds);
2273 while (p) {
2274 req = rb_entry(p, struct ceph_mds_request, r_node);
2275 p = rb_next(p);
2276 if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
2277 continue;
2278 if (req->r_attempts > 0)
2279 continue; /* only new requests */
2280 if (req->r_session &&
2281 req->r_session->s_mds == mds) {
2282 dout(" kicking tid %llu\n", req->r_tid);
2283 list_del_init(&req->r_wait);
2284 __do_request(mdsc, req);
2285 }
2286 }
2287 }
2288
2289 void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
2290 struct ceph_mds_request *req)
2291 {
2292 dout("submit_request on %p\n", req);
2293 mutex_lock(&mdsc->mutex);
2294 __register_request(mdsc, req, NULL);
2295 __do_request(mdsc, req);
2296 mutex_unlock(&mdsc->mutex);
2297 }
2298
2299 /*
2300 * Synchrously perform an mds request. Take care of all of the
2301 * session setup, forwarding, retry details.
2302 */
2303 int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
2304 struct inode *dir,
2305 struct ceph_mds_request *req)
2306 {
2307 int err;
2308
2309 dout("do_request on %p\n", req);
2310
2311 /* take CAP_PIN refs for r_inode, r_parent, r_old_dentry */
2312 if (req->r_inode)
2313 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
2314 if (req->r_parent)
2315 ceph_get_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
2316 if (req->r_old_dentry_dir)
2317 ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
2318 CEPH_CAP_PIN);
2319
2320 /* issue */
2321 mutex_lock(&mdsc->mutex);
2322 __register_request(mdsc, req, dir);
2323 __do_request(mdsc, req);
2324
2325 if (req->r_err) {
2326 err = req->r_err;
2327 goto out;
2328 }
2329
2330 /* wait */
2331 mutex_unlock(&mdsc->mutex);
2332 dout("do_request waiting\n");
2333 if (!req->r_timeout && req->r_wait_for_completion) {
2334 err = req->r_wait_for_completion(mdsc, req);
2335 } else {
2336 long timeleft = wait_for_completion_killable_timeout(
2337 &req->r_completion,
2338 ceph_timeout_jiffies(req->r_timeout));
2339 if (timeleft > 0)
2340 err = 0;
2341 else if (!timeleft)
2342 err = -EIO; /* timed out */
2343 else
2344 err = timeleft; /* killed */
2345 }
2346 dout("do_request waited, got %d\n", err);
2347 mutex_lock(&mdsc->mutex);
2348
2349 /* only abort if we didn't race with a real reply */
2350 if (test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags)) {
2351 err = le32_to_cpu(req->r_reply_info.head->result);
2352 } else if (err < 0) {
2353 dout("aborted request %lld with %d\n", req->r_tid, err);
2354
2355 /*
2356 * ensure we aren't running concurrently with
2357 * ceph_fill_trace or ceph_readdir_prepopulate, which
2358 * rely on locks (dir mutex) held by our caller.
2359 */
2360 mutex_lock(&req->r_fill_mutex);
2361 req->r_err = err;
2362 set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
2363 mutex_unlock(&req->r_fill_mutex);
2364
2365 if (req->r_parent &&
2366 (req->r_op & CEPH_MDS_OP_WRITE))
2367 ceph_invalidate_dir_request(req);
2368 } else {
2369 err = req->r_err;
2370 }
2371
2372 out:
2373 mutex_unlock(&mdsc->mutex);
2374 dout("do_request %p done, result %d\n", req, err);
2375 return err;
2376 }
2377
2378 /*
2379 * Invalidate dir's completeness, dentry lease state on an aborted MDS
2380 * namespace request.
2381 */
2382 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
2383 {
2384 struct inode *inode = req->r_parent;
2385
2386 dout("invalidate_dir_request %p (complete, lease(s))\n", inode);
2387
2388 ceph_dir_clear_complete(inode);
2389 if (req->r_dentry)
2390 ceph_invalidate_dentry_lease(req->r_dentry);
2391 if (req->r_old_dentry)
2392 ceph_invalidate_dentry_lease(req->r_old_dentry);
2393 }
2394
2395 /*
2396 * Handle mds reply.
2397 *
2398 * We take the session mutex and parse and process the reply immediately.
2399 * This preserves the logical ordering of replies, capabilities, etc., sent
2400 * by the MDS as they are applied to our local cache.
2401 */
2402 static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
2403 {
2404 struct ceph_mds_client *mdsc = session->s_mdsc;
2405 struct ceph_mds_request *req;
2406 struct ceph_mds_reply_head *head = msg->front.iov_base;
2407 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
2408 struct ceph_snap_realm *realm;
2409 u64 tid;
2410 int err, result;
2411 int mds = session->s_mds;
2412
2413 if (msg->front.iov_len < sizeof(*head)) {
2414 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
2415 ceph_msg_dump(msg);
2416 return;
2417 }
2418
2419 /* get request, session */
2420 tid = le64_to_cpu(msg->hdr.tid);
2421 mutex_lock(&mdsc->mutex);
2422 req = lookup_get_request(mdsc, tid);
2423 if (!req) {
2424 dout("handle_reply on unknown tid %llu\n", tid);
2425 mutex_unlock(&mdsc->mutex);
2426 return;
2427 }
2428 dout("handle_reply %p\n", req);
2429
2430 /* correct session? */
2431 if (req->r_session != session) {
2432 pr_err("mdsc_handle_reply got %llu on session mds%d"
2433 " not mds%d\n", tid, session->s_mds,
2434 req->r_session ? req->r_session->s_mds : -1);
2435 mutex_unlock(&mdsc->mutex);
2436 goto out;
2437 }
2438
2439 /* dup? */
2440 if ((test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags) && !head->safe) ||
2441 (test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags) && head->safe)) {
2442 pr_warn("got a dup %s reply on %llu from mds%d\n",
2443 head->safe ? "safe" : "unsafe", tid, mds);
2444 mutex_unlock(&mdsc->mutex);
2445 goto out;
2446 }
2447 if (test_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags)) {
2448 pr_warn("got unsafe after safe on %llu from mds%d\n",
2449 tid, mds);
2450 mutex_unlock(&mdsc->mutex);
2451 goto out;
2452 }
2453
2454 result = le32_to_cpu(head->result);
2455
2456 /*
2457 * Handle an ESTALE
2458 * if we're not talking to the authority, send to them
2459 * if the authority has changed while we weren't looking,
2460 * send to new authority
2461 * Otherwise we just have to return an ESTALE
2462 */
2463 if (result == -ESTALE) {
2464 dout("got ESTALE on request %llu", req->r_tid);
2465 req->r_resend_mds = -1;
2466 if (req->r_direct_mode != USE_AUTH_MDS) {
2467 dout("not using auth, setting for that now");
2468 req->r_direct_mode = USE_AUTH_MDS;
2469 __do_request(mdsc, req);
2470 mutex_unlock(&mdsc->mutex);
2471 goto out;
2472 } else {
2473 int mds = __choose_mds(mdsc, req);
2474 if (mds >= 0 && mds != req->r_session->s_mds) {
2475 dout("but auth changed, so resending");
2476 __do_request(mdsc, req);
2477 mutex_unlock(&mdsc->mutex);
2478 goto out;
2479 }
2480 }
2481 dout("have to return ESTALE on request %llu", req->r_tid);
2482 }
2483
2484
2485 if (head->safe) {
2486 set_bit(CEPH_MDS_R_GOT_SAFE, &req->r_req_flags);
2487 __unregister_request(mdsc, req);
2488
2489 if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
2490 /*
2491 * We already handled the unsafe response, now do the
2492 * cleanup. No need to examine the response; the MDS
2493 * doesn't include any result info in the safe
2494 * response. And even if it did, there is nothing
2495 * useful we could do with a revised return value.
2496 */
2497 dout("got safe reply %llu, mds%d\n", tid, mds);
2498
2499 /* last unsafe request during umount? */
2500 if (mdsc->stopping && !__get_oldest_req(mdsc))
2501 complete_all(&mdsc->safe_umount_waiters);
2502 mutex_unlock(&mdsc->mutex);
2503 goto out;
2504 }
2505 } else {
2506 set_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags);
2507 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
2508 if (req->r_unsafe_dir) {
2509 struct ceph_inode_info *ci =
2510 ceph_inode(req->r_unsafe_dir);
2511 spin_lock(&ci->i_unsafe_lock);
2512 list_add_tail(&req->r_unsafe_dir_item,
2513 &ci->i_unsafe_dirops);
2514 spin_unlock(&ci->i_unsafe_lock);
2515 }
2516 }
2517
2518 dout("handle_reply tid %lld result %d\n", tid, result);
2519 rinfo = &req->r_reply_info;
2520 err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
2521 mutex_unlock(&mdsc->mutex);
2522
2523 mutex_lock(&session->s_mutex);
2524 if (err < 0) {
2525 pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
2526 ceph_msg_dump(msg);
2527 goto out_err;
2528 }
2529
2530 /* snap trace */
2531 realm = NULL;
2532 if (rinfo->snapblob_len) {
2533 down_write(&mdsc->snap_rwsem);
2534 ceph_update_snap_trace(mdsc, rinfo->snapblob,
2535 rinfo->snapblob + rinfo->snapblob_len,
2536 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP,
2537 &realm);
2538 downgrade_write(&mdsc->snap_rwsem);
2539 } else {
2540 down_read(&mdsc->snap_rwsem);
2541 }
2542
2543 /* insert trace into our cache */
2544 mutex_lock(&req->r_fill_mutex);
2545 current->journal_info = req;
2546 err = ceph_fill_trace(mdsc->fsc->sb, req);
2547 if (err == 0) {
2548 if (result == 0 && (req->r_op == CEPH_MDS_OP_READDIR ||
2549 req->r_op == CEPH_MDS_OP_LSSNAP))
2550 ceph_readdir_prepopulate(req, req->r_session);
2551 ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
2552 }
2553 current->journal_info = NULL;
2554 mutex_unlock(&req->r_fill_mutex);
2555
2556 up_read(&mdsc->snap_rwsem);
2557 if (realm)
2558 ceph_put_snap_realm(mdsc, realm);
2559
2560 if (err == 0 && req->r_target_inode &&
2561 test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags)) {
2562 struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
2563 spin_lock(&ci->i_unsafe_lock);
2564 list_add_tail(&req->r_unsafe_target_item, &ci->i_unsafe_iops);
2565 spin_unlock(&ci->i_unsafe_lock);
2566 }
2567 out_err:
2568 mutex_lock(&mdsc->mutex);
2569 if (!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
2570 if (err) {
2571 req->r_err = err;
2572 } else {
2573 req->r_reply = ceph_msg_get(msg);
2574 set_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags);
2575 }
2576 } else {
2577 dout("reply arrived after request %lld was aborted\n", tid);
2578 }
2579 mutex_unlock(&mdsc->mutex);
2580
2581 mutex_unlock(&session->s_mutex);
2582
2583 /* kick calling process */
2584 complete_request(mdsc, req);
2585 out:
2586 ceph_mdsc_put_request(req);
2587 return;
2588 }
2589
2590
2591
2592 /*
2593 * handle mds notification that our request has been forwarded.
2594 */
2595 static void handle_forward(struct ceph_mds_client *mdsc,
2596 struct ceph_mds_session *session,
2597 struct ceph_msg *msg)
2598 {
2599 struct ceph_mds_request *req;
2600 u64 tid = le64_to_cpu(msg->hdr.tid);
2601 u32 next_mds;
2602 u32 fwd_seq;
2603 int err = -EINVAL;
2604 void *p = msg->front.iov_base;
2605 void *end = p + msg->front.iov_len;
2606
2607 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
2608 next_mds = ceph_decode_32(&p);
2609 fwd_seq = ceph_decode_32(&p);
2610
2611 mutex_lock(&mdsc->mutex);
2612 req = lookup_get_request(mdsc, tid);
2613 if (!req) {
2614 dout("forward tid %llu to mds%d - req dne\n", tid, next_mds);
2615 goto out; /* dup reply? */
2616 }
2617
2618 if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
2619 dout("forward tid %llu aborted, unregistering\n", tid);
2620 __unregister_request(mdsc, req);
2621 } else if (fwd_seq <= req->r_num_fwd) {
2622 dout("forward tid %llu to mds%d - old seq %d <= %d\n",
2623 tid, next_mds, req->r_num_fwd, fwd_seq);
2624 } else {
2625 /* resend. forward race not possible; mds would drop */
2626 dout("forward tid %llu to mds%d (we resend)\n", tid, next_mds);
2627 BUG_ON(req->r_err);
2628 BUG_ON(test_bit(CEPH_MDS_R_GOT_RESULT, &req->r_req_flags));
2629 req->r_attempts = 0;
2630 req->r_num_fwd = fwd_seq;
2631 req->r_resend_mds = next_mds;
2632 put_request_session(req);
2633 __do_request(mdsc, req);
2634 }
2635 ceph_mdsc_put_request(req);
2636 out:
2637 mutex_unlock(&mdsc->mutex);
2638 return;
2639
2640 bad:
2641 pr_err("mdsc_handle_forward decode error err=%d\n", err);
2642 }
2643
2644 /*
2645 * handle a mds session control message
2646 */
2647 static void handle_session(struct ceph_mds_session *session,
2648 struct ceph_msg *msg)
2649 {
2650 struct ceph_mds_client *mdsc = session->s_mdsc;
2651 u32 op;
2652 u64 seq;
2653 int mds = session->s_mds;
2654 struct ceph_mds_session_head *h = msg->front.iov_base;
2655 int wake = 0;
2656
2657 /* decode */
2658 if (msg->front.iov_len != sizeof(*h))
2659 goto bad;
2660 op = le32_to_cpu(h->op);
2661 seq = le64_to_cpu(h->seq);
2662
2663 mutex_lock(&mdsc->mutex);
2664 if (op == CEPH_SESSION_CLOSE) {
2665 get_session(session);
2666 __unregister_session(mdsc, session);
2667 }
2668 /* FIXME: this ttl calculation is generous */
2669 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2670 mutex_unlock(&mdsc->mutex);
2671
2672 mutex_lock(&session->s_mutex);
2673
2674 dout("handle_session mds%d %s %p state %s seq %llu\n",
2675 mds, ceph_session_op_name(op), session,
2676 ceph_session_state_name(session->s_state), seq);
2677
2678 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2679 session->s_state = CEPH_MDS_SESSION_OPEN;
2680 pr_info("mds%d came back\n", session->s_mds);
2681 }
2682
2683 switch (op) {
2684 case CEPH_SESSION_OPEN:
2685 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2686 pr_info("mds%d reconnect success\n", session->s_mds);
2687 session->s_state = CEPH_MDS_SESSION_OPEN;
2688 renewed_caps(mdsc, session, 0);
2689 wake = 1;
2690 if (mdsc->stopping)
2691 __close_session(mdsc, session);
2692 break;
2693
2694 case CEPH_SESSION_RENEWCAPS:
2695 if (session->s_renew_seq == seq)
2696 renewed_caps(mdsc, session, 1);
2697 break;
2698
2699 case CEPH_SESSION_CLOSE:
2700 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2701 pr_info("mds%d reconnect denied\n", session->s_mds);
2702 cleanup_session_requests(mdsc, session);
2703 remove_session_caps(session);
2704 wake = 2; /* for good measure */
2705 wake_up_all(&mdsc->session_close_wq);
2706 break;
2707
2708 case CEPH_SESSION_STALE:
2709 pr_info("mds%d caps went stale, renewing\n",
2710 session->s_mds);
2711 spin_lock(&session->s_gen_ttl_lock);
2712 session->s_cap_gen++;
2713 session->s_cap_ttl = jiffies - 1;
2714 spin_unlock(&session->s_gen_ttl_lock);
2715 send_renew_caps(mdsc, session);
2716 break;
2717
2718 case CEPH_SESSION_RECALL_STATE:
2719 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2720 break;
2721
2722 case CEPH_SESSION_FLUSHMSG:
2723 send_flushmsg_ack(mdsc, session, seq);
2724 break;
2725
2726 case CEPH_SESSION_FORCE_RO:
2727 dout("force_session_readonly %p\n", session);
2728 spin_lock(&session->s_cap_lock);
2729 session->s_readonly = true;
2730 spin_unlock(&session->s_cap_lock);
2731 wake_up_session_caps(session, 0);
2732 break;
2733
2734 case CEPH_SESSION_REJECT:
2735 WARN_ON(session->s_state != CEPH_MDS_SESSION_OPENING);
2736 pr_info("mds%d rejected session\n", session->s_mds);
2737 session->s_state = CEPH_MDS_SESSION_REJECTED;
2738 cleanup_session_requests(mdsc, session);
2739 remove_session_caps(session);
2740 wake = 2; /* for good measure */
2741 break;
2742
2743 default:
2744 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2745 WARN_ON(1);
2746 }
2747
2748 mutex_unlock(&session->s_mutex);
2749 if (wake) {
2750 mutex_lock(&mdsc->mutex);
2751 __wake_requests(mdsc, &session->s_waiting);
2752 if (wake == 2)
2753 kick_requests(mdsc, mds);
2754 mutex_unlock(&mdsc->mutex);
2755 }
2756 if (op == CEPH_SESSION_CLOSE)
2757 ceph_put_mds_session(session);
2758 return;
2759
2760 bad:
2761 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2762 (int)msg->front.iov_len);
2763 ceph_msg_dump(msg);
2764 return;
2765 }
2766
2767
2768 /*
2769 * called under session->mutex.
2770 */
2771 static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2772 struct ceph_mds_session *session)
2773 {
2774 struct ceph_mds_request *req, *nreq;
2775 struct rb_node *p;
2776 int err;
2777
2778 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2779
2780 mutex_lock(&mdsc->mutex);
2781 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2782 err = __prepare_send_request(mdsc, req, session->s_mds, true);
2783 if (!err) {
2784 ceph_msg_get(req->r_request);
2785 ceph_con_send(&session->s_con, req->r_request);
2786 }
2787 }
2788
2789 /*
2790 * also re-send old requests when MDS enters reconnect stage. So that MDS
2791 * can process completed request in clientreplay stage.
2792 */
2793 p = rb_first(&mdsc->request_tree);
2794 while (p) {
2795 req = rb_entry(p, struct ceph_mds_request, r_node);
2796 p = rb_next(p);
2797 if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
2798 continue;
2799 if (req->r_attempts == 0)
2800 continue; /* only old requests */
2801 if (req->r_session &&
2802 req->r_session->s_mds == session->s_mds) {
2803 err = __prepare_send_request(mdsc, req,
2804 session->s_mds, true);
2805 if (!err) {
2806 ceph_msg_get(req->r_request);
2807 ceph_con_send(&session->s_con, req->r_request);
2808 }
2809 }
2810 }
2811 mutex_unlock(&mdsc->mutex);
2812 }
2813
2814 /*
2815 * Encode information about a cap for a reconnect with the MDS.
2816 */
2817 static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2818 void *arg)
2819 {
2820 union {
2821 struct ceph_mds_cap_reconnect v2;
2822 struct ceph_mds_cap_reconnect_v1 v1;
2823 } rec;
2824 struct ceph_inode_info *ci;
2825 struct ceph_reconnect_state *recon_state = arg;
2826 struct ceph_pagelist *pagelist = recon_state->pagelist;
2827 char *path;
2828 int pathlen, err;
2829 u64 pathbase;
2830 u64 snap_follows;
2831 struct dentry *dentry;
2832
2833 ci = cap->ci;
2834
2835 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2836 inode, ceph_vinop(inode), cap, cap->cap_id,
2837 ceph_cap_string(cap->issued));
2838 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2839 if (err)
2840 return err;
2841
2842 dentry = d_find_alias(inode);
2843 if (dentry) {
2844 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2845 if (IS_ERR(path)) {
2846 err = PTR_ERR(path);
2847 goto out_dput;
2848 }
2849 } else {
2850 path = NULL;
2851 pathlen = 0;
2852 pathbase = 0;
2853 }
2854
2855 spin_lock(&ci->i_ceph_lock);
2856 cap->seq = 0; /* reset cap seq */
2857 cap->issue_seq = 0; /* and issue_seq */
2858 cap->mseq = 0; /* and migrate_seq */
2859 cap->cap_gen = cap->session->s_cap_gen;
2860
2861 if (recon_state->msg_version >= 2) {
2862 rec.v2.cap_id = cpu_to_le64(cap->cap_id);
2863 rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2864 rec.v2.issued = cpu_to_le32(cap->issued);
2865 rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2866 rec.v2.pathbase = cpu_to_le64(pathbase);
2867 rec.v2.flock_len = 0;
2868 } else {
2869 rec.v1.cap_id = cpu_to_le64(cap->cap_id);
2870 rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2871 rec.v1.issued = cpu_to_le32(cap->issued);
2872 rec.v1.size = cpu_to_le64(inode->i_size);
2873 ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
2874 ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
2875 rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2876 rec.v1.pathbase = cpu_to_le64(pathbase);
2877 }
2878
2879 if (list_empty(&ci->i_cap_snaps)) {
2880 snap_follows = 0;
2881 } else {
2882 struct ceph_cap_snap *capsnap =
2883 list_first_entry(&ci->i_cap_snaps,
2884 struct ceph_cap_snap, ci_item);
2885 snap_follows = capsnap->follows;
2886 }
2887 spin_unlock(&ci->i_ceph_lock);
2888
2889 if (recon_state->msg_version >= 2) {
2890 int num_fcntl_locks, num_flock_locks;
2891 struct ceph_filelock *flocks;
2892 size_t struct_len, total_len = 0;
2893 u8 struct_v = 0;
2894
2895 encode_again:
2896 ceph_count_locks(inode, &num_fcntl_locks, &num_flock_locks);
2897 flocks = kmalloc((num_fcntl_locks+num_flock_locks) *
2898 sizeof(struct ceph_filelock), GFP_NOFS);
2899 if (!flocks) {
2900 err = -ENOMEM;
2901 goto out_free;
2902 }
2903 err = ceph_encode_locks_to_buffer(inode, flocks,
2904 num_fcntl_locks,
2905 num_flock_locks);
2906 if (err) {
2907 kfree(flocks);
2908 if (err == -ENOSPC)
2909 goto encode_again;
2910 goto out_free;
2911 }
2912
2913 if (recon_state->msg_version >= 3) {
2914 /* version, compat_version and struct_len */
2915 total_len = 2 * sizeof(u8) + sizeof(u32);
2916 struct_v = 2;
2917 }
2918 /*
2919 * number of encoded locks is stable, so copy to pagelist
2920 */
2921 struct_len = 2 * sizeof(u32) +
2922 (num_fcntl_locks + num_flock_locks) *
2923 sizeof(struct ceph_filelock);
2924 rec.v2.flock_len = cpu_to_le32(struct_len);
2925
2926 struct_len += sizeof(rec.v2);
2927 struct_len += sizeof(u32) + pathlen;
2928
2929 if (struct_v >= 2)
2930 struct_len += sizeof(u64); /* snap_follows */
2931
2932 total_len += struct_len;
2933 err = ceph_pagelist_reserve(pagelist, total_len);
2934
2935 if (!err) {
2936 if (recon_state->msg_version >= 3) {
2937 ceph_pagelist_encode_8(pagelist, struct_v);
2938 ceph_pagelist_encode_8(pagelist, 1);
2939 ceph_pagelist_encode_32(pagelist, struct_len);
2940 }
2941 ceph_pagelist_encode_string(pagelist, path, pathlen);
2942 ceph_pagelist_append(pagelist, &rec, sizeof(rec.v2));
2943 ceph_locks_to_pagelist(flocks, pagelist,
2944 num_fcntl_locks,
2945 num_flock_locks);
2946 if (struct_v >= 2)
2947 ceph_pagelist_encode_64(pagelist, snap_follows);
2948 }
2949 kfree(flocks);
2950 } else {
2951 size_t size = sizeof(u32) + pathlen + sizeof(rec.v1);
2952 err = ceph_pagelist_reserve(pagelist, size);
2953 if (!err) {
2954 ceph_pagelist_encode_string(pagelist, path, pathlen);
2955 ceph_pagelist_append(pagelist, &rec, sizeof(rec.v1));
2956 }
2957 }
2958
2959 recon_state->nr_caps++;
2960 out_free:
2961 kfree(path);
2962 out_dput:
2963 dput(dentry);
2964 return err;
2965 }
2966
2967
2968 /*
2969 * If an MDS fails and recovers, clients need to reconnect in order to
2970 * reestablish shared state. This includes all caps issued through
2971 * this session _and_ the snap_realm hierarchy. Because it's not
2972 * clear which snap realms the mds cares about, we send everything we
2973 * know about.. that ensures we'll then get any new info the
2974 * recovering MDS might have.
2975 *
2976 * This is a relatively heavyweight operation, but it's rare.
2977 *
2978 * called with mdsc->mutex held.
2979 */
2980 static void send_mds_reconnect(struct ceph_mds_client *mdsc,
2981 struct ceph_mds_session *session)
2982 {
2983 struct ceph_msg *reply;
2984 struct rb_node *p;
2985 int mds = session->s_mds;
2986 int err = -ENOMEM;
2987 int s_nr_caps;
2988 struct ceph_pagelist *pagelist;
2989 struct ceph_reconnect_state recon_state;
2990
2991 pr_info("mds%d reconnect start\n", mds);
2992
2993 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2994 if (!pagelist)
2995 goto fail_nopagelist;
2996 ceph_pagelist_init(pagelist);
2997
2998 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS, false);
2999 if (!reply)
3000 goto fail_nomsg;
3001
3002 mutex_lock(&session->s_mutex);
3003 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
3004 session->s_seq = 0;
3005
3006 dout("session %p state %s\n", session,
3007 ceph_session_state_name(session->s_state));
3008
3009 spin_lock(&session->s_gen_ttl_lock);
3010 session->s_cap_gen++;
3011 spin_unlock(&session->s_gen_ttl_lock);
3012
3013 spin_lock(&session->s_cap_lock);
3014 /* don't know if session is readonly */
3015 session->s_readonly = 0;
3016 /*
3017 * notify __ceph_remove_cap() that we are composing cap reconnect.
3018 * If a cap get released before being added to the cap reconnect,
3019 * __ceph_remove_cap() should skip queuing cap release.
3020 */
3021 session->s_cap_reconnect = 1;
3022 /* drop old cap expires; we're about to reestablish that state */
3023 cleanup_cap_releases(mdsc, session);
3024
3025 /* trim unused caps to reduce MDS's cache rejoin time */
3026 if (mdsc->fsc->sb->s_root)
3027 shrink_dcache_parent(mdsc->fsc->sb->s_root);
3028
3029 ceph_con_close(&session->s_con);
3030 ceph_con_open(&session->s_con,
3031 CEPH_ENTITY_TYPE_MDS, mds,
3032 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
3033
3034 /* replay unsafe requests */
3035 replay_unsafe_requests(mdsc, session);
3036
3037 down_read(&mdsc->snap_rwsem);
3038
3039 /* traverse this session's caps */
3040 s_nr_caps = session->s_nr_caps;
3041 err = ceph_pagelist_encode_32(pagelist, s_nr_caps);
3042 if (err)
3043 goto fail;
3044
3045 recon_state.nr_caps = 0;
3046 recon_state.pagelist = pagelist;
3047 if (session->s_con.peer_features & CEPH_FEATURE_MDSENC)
3048 recon_state.msg_version = 3;
3049 else if (session->s_con.peer_features & CEPH_FEATURE_FLOCK)
3050 recon_state.msg_version = 2;
3051 else
3052 recon_state.msg_version = 1;
3053 err = iterate_session_caps(session, encode_caps_cb, &recon_state);
3054 if (err < 0)
3055 goto fail;
3056
3057 spin_lock(&session->s_cap_lock);
3058 session->s_cap_reconnect = 0;
3059 spin_unlock(&session->s_cap_lock);
3060
3061 /*
3062 * snaprealms. we provide mds with the ino, seq (version), and
3063 * parent for all of our realms. If the mds has any newer info,
3064 * it will tell us.
3065 */
3066 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
3067 struct ceph_snap_realm *realm =
3068 rb_entry(p, struct ceph_snap_realm, node);
3069 struct ceph_mds_snaprealm_reconnect sr_rec;
3070
3071 dout(" adding snap realm %llx seq %lld parent %llx\n",
3072 realm->ino, realm->seq, realm->parent_ino);
3073 sr_rec.ino = cpu_to_le64(realm->ino);
3074 sr_rec.seq = cpu_to_le64(realm->seq);
3075 sr_rec.parent = cpu_to_le64(realm->parent_ino);
3076 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
3077 if (err)
3078 goto fail;
3079 }
3080
3081 reply->hdr.version = cpu_to_le16(recon_state.msg_version);
3082
3083 /* raced with cap release? */
3084 if (s_nr_caps != recon_state.nr_caps) {
3085 struct page *page = list_first_entry(&pagelist->head,
3086 struct page, lru);
3087 __le32 *addr = kmap_atomic(page);
3088 *addr = cpu_to_le32(recon_state.nr_caps);
3089 kunmap_atomic(addr);
3090 }
3091
3092 reply->hdr.data_len = cpu_to_le32(pagelist->length);
3093 ceph_msg_data_add_pagelist(reply, pagelist);
3094
3095 ceph_early_kick_flushing_caps(mdsc, session);
3096
3097 ceph_con_send(&session->s_con, reply);
3098
3099 mutex_unlock(&session->s_mutex);
3100
3101 mutex_lock(&mdsc->mutex);
3102 __wake_requests(mdsc, &session->s_waiting);
3103 mutex_unlock(&mdsc->mutex);
3104
3105 up_read(&mdsc->snap_rwsem);
3106 return;
3107
3108 fail:
3109 ceph_msg_put(reply);
3110 up_read(&mdsc->snap_rwsem);
3111 mutex_unlock(&session->s_mutex);
3112 fail_nomsg:
3113 ceph_pagelist_release(pagelist);
3114 fail_nopagelist:
3115 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
3116 return;
3117 }
3118
3119
3120 /*
3121 * compare old and new mdsmaps, kicking requests
3122 * and closing out old connections as necessary
3123 *
3124 * called under mdsc->mutex.
3125 */
3126 static void check_new_map(struct ceph_mds_client *mdsc,
3127 struct ceph_mdsmap *newmap,
3128 struct ceph_mdsmap *oldmap)
3129 {
3130 int i;
3131 int oldstate, newstate;
3132 struct ceph_mds_session *s;
3133
3134 dout("check_new_map new %u old %u\n",
3135 newmap->m_epoch, oldmap->m_epoch);
3136
3137 for (i = 0; i < oldmap->m_num_mds && i < mdsc->max_sessions; i++) {
3138 if (mdsc->sessions[i] == NULL)
3139 continue;
3140 s = mdsc->sessions[i];
3141 oldstate = ceph_mdsmap_get_state(oldmap, i);
3142 newstate = ceph_mdsmap_get_state(newmap, i);
3143
3144 dout("check_new_map mds%d state %s%s -> %s%s (session %s)\n",
3145 i, ceph_mds_state_name(oldstate),
3146 ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "",
3147 ceph_mds_state_name(newstate),
3148 ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
3149 ceph_session_state_name(s->s_state));
3150
3151 if (i >= newmap->m_num_mds ||
3152 memcmp(ceph_mdsmap_get_addr(oldmap, i),
3153 ceph_mdsmap_get_addr(newmap, i),
3154 sizeof(struct ceph_entity_addr))) {
3155 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
3156 /* the session never opened, just close it
3157 * out now */
3158 get_session(s);
3159 __unregister_session(mdsc, s);
3160 __wake_requests(mdsc, &s->s_waiting);
3161 ceph_put_mds_session(s);
3162 } else if (i >= newmap->m_num_mds) {
3163 /* force close session for stopped mds */
3164 get_session(s);
3165 __unregister_session(mdsc, s);
3166 __wake_requests(mdsc, &s->s_waiting);
3167 kick_requests(mdsc, i);
3168 mutex_unlock(&mdsc->mutex);
3169
3170 mutex_lock(&s->s_mutex);
3171 cleanup_session_requests(mdsc, s);
3172 remove_session_caps(s);
3173 mutex_unlock(&s->s_mutex);
3174
3175 ceph_put_mds_session(s);
3176
3177 mutex_lock(&mdsc->mutex);
3178 } else {
3179 /* just close it */
3180 mutex_unlock(&mdsc->mutex);
3181 mutex_lock(&s->s_mutex);
3182 mutex_lock(&mdsc->mutex);
3183 ceph_con_close(&s->s_con);
3184 mutex_unlock(&s->s_mutex);
3185 s->s_state = CEPH_MDS_SESSION_RESTARTING;
3186 }
3187 } else if (oldstate == newstate) {
3188 continue; /* nothing new with this mds */
3189 }
3190
3191 /*
3192 * send reconnect?
3193 */
3194 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
3195 newstate >= CEPH_MDS_STATE_RECONNECT) {
3196 mutex_unlock(&mdsc->mutex);
3197 send_mds_reconnect(mdsc, s);
3198 mutex_lock(&mdsc->mutex);
3199 }
3200
3201 /*
3202 * kick request on any mds that has gone active.
3203 */
3204 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
3205 newstate >= CEPH_MDS_STATE_ACTIVE) {
3206 if (oldstate != CEPH_MDS_STATE_CREATING &&
3207 oldstate != CEPH_MDS_STATE_STARTING)
3208 pr_info("mds%d recovery completed\n", s->s_mds);
3209 kick_requests(mdsc, i);
3210 ceph_kick_flushing_caps(mdsc, s);
3211 wake_up_session_caps(s, 1);
3212 }
3213 }
3214
3215 for (i = 0; i < newmap->m_num_mds && i < mdsc->max_sessions; i++) {
3216 s = mdsc->sessions[i];
3217 if (!s)
3218 continue;
3219 if (!ceph_mdsmap_is_laggy(newmap, i))
3220 continue;
3221 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
3222 s->s_state == CEPH_MDS_SESSION_HUNG ||
3223 s->s_state == CEPH_MDS_SESSION_CLOSING) {
3224 dout(" connecting to export targets of laggy mds%d\n",
3225 i);
3226 __open_export_target_sessions(mdsc, s);
3227 }
3228 }
3229 }
3230
3231
3232
3233 /*
3234 * leases
3235 */
3236
3237 /*
3238 * caller must hold session s_mutex, dentry->d_lock
3239 */
3240 void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
3241 {
3242 struct ceph_dentry_info *di = ceph_dentry(dentry);
3243
3244 ceph_put_mds_session(di->lease_session);
3245 di->lease_session = NULL;
3246 }
3247
3248 static void handle_lease(struct ceph_mds_client *mdsc,
3249 struct ceph_mds_session *session,
3250 struct ceph_msg *msg)
3251 {
3252 struct super_block *sb = mdsc->fsc->sb;
3253 struct inode *inode;
3254 struct dentry *parent, *dentry;
3255 struct ceph_dentry_info *di;
3256 int mds = session->s_mds;
3257 struct ceph_mds_lease *h = msg->front.iov_base;
3258 u32 seq;
3259 struct ceph_vino vino;
3260 struct qstr dname;
3261 int release = 0;
3262
3263 dout("handle_lease from mds%d\n", mds);
3264
3265 /* decode */
3266 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
3267 goto bad;
3268 vino.ino = le64_to_cpu(h->ino);
3269 vino.snap = CEPH_NOSNAP;
3270 seq = le32_to_cpu(h->seq);
3271 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
3272 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
3273 if (dname.len != get_unaligned_le32(h+1))
3274 goto bad;
3275
3276 /* lookup inode */
3277 inode = ceph_find_inode(sb, vino);
3278 dout("handle_lease %s, ino %llx %p %.*s\n",
3279 ceph_lease_op_name(h->action), vino.ino, inode,
3280 dname.len, dname.name);
3281
3282 mutex_lock(&session->s_mutex);
3283 session->s_seq++;
3284
3285 if (inode == NULL) {
3286 dout("handle_lease no inode %llx\n", vino.ino);
3287 goto release;
3288 }
3289
3290 /* dentry */
3291 parent = d_find_alias(inode);
3292 if (!parent) {
3293 dout("no parent dentry on inode %p\n", inode);
3294 WARN_ON(1);
3295 goto release; /* hrm... */
3296 }
3297 dname.hash = full_name_hash(parent, dname.name, dname.len);
3298 dentry = d_lookup(parent, &dname);
3299 dput(parent);
3300 if (!dentry)
3301 goto release;
3302
3303 spin_lock(&dentry->d_lock);
3304 di = ceph_dentry(dentry);
3305 switch (h->action) {
3306 case CEPH_MDS_LEASE_REVOKE:
3307 if (di->lease_session == session) {
3308 if (ceph_seq_cmp(di->lease_seq, seq) > 0)
3309 h->seq = cpu_to_le32(di->lease_seq);
3310 __ceph_mdsc_drop_dentry_lease(dentry);
3311 }
3312 release = 1;
3313 break;
3314
3315 case CEPH_MDS_LEASE_RENEW:
3316 if (di->lease_session == session &&
3317 di->lease_gen == session->s_cap_gen &&
3318 di->lease_renew_from &&
3319 di->lease_renew_after == 0) {
3320 unsigned long duration =
3321 msecs_to_jiffies(le32_to_cpu(h->duration_ms));
3322
3323 di->lease_seq = seq;
3324 di->time = di->lease_renew_from + duration;
3325 di->lease_renew_after = di->lease_renew_from +
3326 (duration >> 1);
3327 di->lease_renew_from = 0;
3328 }
3329 break;
3330 }
3331 spin_unlock(&dentry->d_lock);
3332 dput(dentry);
3333
3334 if (!release)
3335 goto out;
3336
3337 release:
3338 /* let's just reuse the same message */
3339 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
3340 ceph_msg_get(msg);
3341 ceph_con_send(&session->s_con, msg);
3342
3343 out:
3344 iput(inode);
3345 mutex_unlock(&session->s_mutex);
3346 return;
3347
3348 bad:
3349 pr_err("corrupt lease message\n");
3350 ceph_msg_dump(msg);
3351 }
3352
3353 void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
3354 struct inode *inode,
3355 struct dentry *dentry, char action,
3356 u32 seq)
3357 {
3358 struct ceph_msg *msg;
3359 struct ceph_mds_lease *lease;
3360 int len = sizeof(*lease) + sizeof(u32);
3361 int dnamelen = 0;
3362
3363 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
3364 inode, dentry, ceph_lease_op_name(action), session->s_mds);
3365 dnamelen = dentry->d_name.len;
3366 len += dnamelen;
3367
3368 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false);
3369 if (!msg)
3370 return;
3371 lease = msg->front.iov_base;
3372 lease->action = action;
3373 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
3374 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
3375 lease->seq = cpu_to_le32(seq);
3376 put_unaligned_le32(dnamelen, lease + 1);
3377 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
3378
3379 /*
3380 * if this is a preemptive lease RELEASE, no need to
3381 * flush request stream, since the actual request will
3382 * soon follow.
3383 */
3384 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
3385
3386 ceph_con_send(&session->s_con, msg);
3387 }
3388
3389 /*
3390 * drop all leases (and dentry refs) in preparation for umount
3391 */
3392 static void drop_leases(struct ceph_mds_client *mdsc)
3393 {
3394 int i;
3395
3396 dout("drop_leases\n");
3397 mutex_lock(&mdsc->mutex);
3398 for (i = 0; i < mdsc->max_sessions; i++) {
3399 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
3400 if (!s)
3401 continue;
3402 mutex_unlock(&mdsc->mutex);
3403 mutex_lock(&s->s_mutex);
3404 mutex_unlock(&s->s_mutex);
3405 ceph_put_mds_session(s);
3406 mutex_lock(&mdsc->mutex);
3407 }
3408 mutex_unlock(&mdsc->mutex);
3409 }
3410
3411
3412
3413 /*
3414 * delayed work -- periodically trim expired leases, renew caps with mds
3415 */
3416 static void schedule_delayed(struct ceph_mds_client *mdsc)
3417 {
3418 int delay = 5;
3419 unsigned hz = round_jiffies_relative(HZ * delay);
3420 schedule_delayed_work(&mdsc->delayed_work, hz);
3421 }
3422
3423 static void delayed_work(struct work_struct *work)
3424 {
3425 int i;
3426 struct ceph_mds_client *mdsc =
3427 container_of(work, struct ceph_mds_client, delayed_work.work);
3428 int renew_interval;
3429 int renew_caps;
3430
3431 dout("mdsc delayed_work\n");
3432 ceph_check_delayed_caps(mdsc);
3433
3434 mutex_lock(&mdsc->mutex);
3435 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
3436 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
3437 mdsc->last_renew_caps);
3438 if (renew_caps)
3439 mdsc->last_renew_caps = jiffies;
3440
3441 for (i = 0; i < mdsc->max_sessions; i++) {
3442 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
3443 if (s == NULL)
3444 continue;
3445 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
3446 dout("resending session close request for mds%d\n",
3447 s->s_mds);
3448 request_close_session(mdsc, s);
3449 ceph_put_mds_session(s);
3450 continue;
3451 }
3452 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
3453 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
3454 s->s_state = CEPH_MDS_SESSION_HUNG;
3455 pr_info("mds%d hung\n", s->s_mds);
3456 }
3457 }
3458 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
3459 /* this mds is failed or recovering, just wait */
3460 ceph_put_mds_session(s);
3461 continue;
3462 }
3463 mutex_unlock(&mdsc->mutex);
3464
3465 mutex_lock(&s->s_mutex);
3466 if (renew_caps)
3467 send_renew_caps(mdsc, s);
3468 else
3469 ceph_con_keepalive(&s->s_con);
3470 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
3471 s->s_state == CEPH_MDS_SESSION_HUNG)
3472 ceph_send_cap_releases(mdsc, s);
3473 mutex_unlock(&s->s_mutex);
3474 ceph_put_mds_session(s);
3475
3476 mutex_lock(&mdsc->mutex);
3477 }
3478 mutex_unlock(&mdsc->mutex);
3479
3480 schedule_delayed(mdsc);
3481 }
3482
3483 int ceph_mdsc_init(struct ceph_fs_client *fsc)
3484
3485 {
3486 struct ceph_mds_client *mdsc;
3487
3488 mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS);
3489 if (!mdsc)
3490 return -ENOMEM;
3491 mdsc->fsc = fsc;
3492 fsc->mdsc = mdsc;
3493 mutex_init(&mdsc->mutex);
3494 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
3495 if (mdsc->mdsmap == NULL) {
3496 kfree(mdsc);
3497 return -ENOMEM;
3498 }
3499
3500 init_completion(&mdsc->safe_umount_waiters);
3501 init_waitqueue_head(&mdsc->session_close_wq);
3502 INIT_LIST_HEAD(&mdsc->waiting_for_map);
3503 mdsc->sessions = NULL;
3504 atomic_set(&mdsc->num_sessions, 0);
3505 mdsc->max_sessions = 0;
3506 mdsc->stopping = 0;
3507 mdsc->last_snap_seq = 0;
3508 init_rwsem(&mdsc->snap_rwsem);
3509 mdsc->snap_realms = RB_ROOT;
3510 INIT_LIST_HEAD(&mdsc->snap_empty);
3511 spin_lock_init(&mdsc->snap_empty_lock);
3512 mdsc->last_tid = 0;
3513 mdsc->oldest_tid = 0;
3514 mdsc->request_tree = RB_ROOT;
3515 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
3516 mdsc->last_renew_caps = jiffies;
3517 INIT_LIST_HEAD(&mdsc->cap_delay_list);
3518 spin_lock_init(&mdsc->cap_delay_lock);
3519 INIT_LIST_HEAD(&mdsc->snap_flush_list);
3520 spin_lock_init(&mdsc->snap_flush_lock);
3521 mdsc->last_cap_flush_tid = 1;
3522 INIT_LIST_HEAD(&mdsc->cap_flush_list);
3523 INIT_LIST_HEAD(&mdsc->cap_dirty);
3524 INIT_LIST_HEAD(&mdsc->cap_dirty_migrating);
3525 mdsc->num_cap_flushing = 0;
3526 spin_lock_init(&mdsc->cap_dirty_lock);
3527 init_waitqueue_head(&mdsc->cap_flushing_wq);
3528 spin_lock_init(&mdsc->dentry_lru_lock);
3529 INIT_LIST_HEAD(&mdsc->dentry_lru);
3530
3531 ceph_caps_init(mdsc);
3532 ceph_adjust_min_caps(mdsc, fsc->min_caps);
3533
3534 init_rwsem(&mdsc->pool_perm_rwsem);
3535 mdsc->pool_perm_tree = RB_ROOT;
3536
3537 return 0;
3538 }
3539
3540 /*
3541 * Wait for safe replies on open mds requests. If we time out, drop
3542 * all requests from the tree to avoid dangling dentry refs.
3543 */
3544 static void wait_requests(struct ceph_mds_client *mdsc)
3545 {
3546 struct ceph_options *opts = mdsc->fsc->client->options;
3547 struct ceph_mds_request *req;
3548
3549 mutex_lock(&mdsc->mutex);
3550 if (__get_oldest_req(mdsc)) {
3551 mutex_unlock(&mdsc->mutex);
3552
3553 dout("wait_requests waiting for requests\n");
3554 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
3555 ceph_timeout_jiffies(opts->mount_timeout));
3556
3557 /* tear down remaining requests */
3558 mutex_lock(&mdsc->mutex);
3559 while ((req = __get_oldest_req(mdsc))) {
3560 dout("wait_requests timed out on tid %llu\n",
3561 req->r_tid);
3562 __unregister_request(mdsc, req);
3563 }
3564 }
3565 mutex_unlock(&mdsc->mutex);
3566 dout("wait_requests done\n");
3567 }
3568
3569 /*
3570 * called before mount is ro, and before dentries are torn down.
3571 * (hmm, does this still race with new lookups?)
3572 */
3573 void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
3574 {
3575 dout("pre_umount\n");
3576 mdsc->stopping = 1;
3577
3578 drop_leases(mdsc);
3579 ceph_flush_dirty_caps(mdsc);
3580 wait_requests(mdsc);
3581
3582 /*
3583 * wait for reply handlers to drop their request refs and
3584 * their inode/dcache refs
3585 */
3586 ceph_msgr_flush();
3587 }
3588
3589 /*
3590 * wait for all write mds requests to flush.
3591 */
3592 static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
3593 {
3594 struct ceph_mds_request *req = NULL, *nextreq;
3595 struct rb_node *n;
3596
3597 mutex_lock(&mdsc->mutex);
3598 dout("wait_unsafe_requests want %lld\n", want_tid);
3599 restart:
3600 req = __get_oldest_req(mdsc);
3601 while (req && req->r_tid <= want_tid) {
3602 /* find next request */
3603 n = rb_next(&req->r_node);
3604 if (n)
3605 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
3606 else
3607 nextreq = NULL;
3608 if (req->r_op != CEPH_MDS_OP_SETFILELOCK &&
3609 (req->r_op & CEPH_MDS_OP_WRITE)) {
3610 /* write op */
3611 ceph_mdsc_get_request(req);
3612 if (nextreq)
3613 ceph_mdsc_get_request(nextreq);
3614 mutex_unlock(&mdsc->mutex);
3615 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
3616 req->r_tid, want_tid);
3617 wait_for_completion(&req->r_safe_completion);
3618 mutex_lock(&mdsc->mutex);
3619 ceph_mdsc_put_request(req);
3620 if (!nextreq)
3621 break; /* next dne before, so we're done! */
3622 if (RB_EMPTY_NODE(&nextreq->r_node)) {
3623 /* next request was removed from tree */
3624 ceph_mdsc_put_request(nextreq);
3625 goto restart;
3626 }
3627 ceph_mdsc_put_request(nextreq); /* won't go away */
3628 }
3629 req = nextreq;
3630 }
3631 mutex_unlock(&mdsc->mutex);
3632 dout("wait_unsafe_requests done\n");
3633 }
3634
3635 void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
3636 {
3637 u64 want_tid, want_flush;
3638
3639 if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN)
3640 return;
3641
3642 dout("sync\n");
3643 mutex_lock(&mdsc->mutex);
3644 want_tid = mdsc->last_tid;
3645 mutex_unlock(&mdsc->mutex);
3646
3647 ceph_flush_dirty_caps(mdsc);
3648 spin_lock(&mdsc->cap_dirty_lock);
3649 want_flush = mdsc->last_cap_flush_tid;
3650 if (!list_empty(&mdsc->cap_flush_list)) {
3651 struct ceph_cap_flush *cf =
3652 list_last_entry(&mdsc->cap_flush_list,
3653 struct ceph_cap_flush, g_list);
3654 cf->wake = true;
3655 }
3656 spin_unlock(&mdsc->cap_dirty_lock);
3657
3658 dout("sync want tid %lld flush_seq %lld\n",
3659 want_tid, want_flush);
3660
3661 wait_unsafe_requests(mdsc, want_tid);
3662 wait_caps_flush(mdsc, want_flush);
3663 }
3664
3665 /*
3666 * true if all sessions are closed, or we force unmount
3667 */
3668 static bool done_closing_sessions(struct ceph_mds_client *mdsc, int skipped)
3669 {
3670 if (READ_ONCE(mdsc->fsc->mount_state) == CEPH_MOUNT_SHUTDOWN)
3671 return true;
3672 return atomic_read(&mdsc->num_sessions) <= skipped;
3673 }
3674
3675 /*
3676 * called after sb is ro.
3677 */
3678 void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
3679 {
3680 struct ceph_options *opts = mdsc->fsc->client->options;
3681 struct ceph_mds_session *session;
3682 int i;
3683 int skipped = 0;
3684
3685 dout("close_sessions\n");
3686
3687 /* close sessions */
3688 mutex_lock(&mdsc->mutex);
3689 for (i = 0; i < mdsc->max_sessions; i++) {
3690 session = __ceph_lookup_mds_session(mdsc, i);
3691 if (!session)
3692 continue;
3693 mutex_unlock(&mdsc->mutex);
3694 mutex_lock(&session->s_mutex);
3695 if (__close_session(mdsc, session) <= 0)
3696 skipped++;
3697 mutex_unlock(&session->s_mutex);
3698 ceph_put_mds_session(session);
3699 mutex_lock(&mdsc->mutex);
3700 }
3701 mutex_unlock(&mdsc->mutex);
3702
3703 dout("waiting for sessions to close\n");
3704 wait_event_timeout(mdsc->session_close_wq,
3705 done_closing_sessions(mdsc, skipped),
3706 ceph_timeout_jiffies(opts->mount_timeout));
3707
3708 /* tear down remaining sessions */
3709 mutex_lock(&mdsc->mutex);
3710 for (i = 0; i < mdsc->max_sessions; i++) {
3711 if (mdsc->sessions[i]) {
3712 session = get_session(mdsc->sessions[i]);
3713 __unregister_session(mdsc, session);
3714 mutex_unlock(&mdsc->mutex);
3715 mutex_lock(&session->s_mutex);
3716 remove_session_caps(session);
3717 mutex_unlock(&session->s_mutex);
3718 ceph_put_mds_session(session);
3719 mutex_lock(&mdsc->mutex);
3720 }
3721 }
3722 WARN_ON(!list_empty(&mdsc->cap_delay_list));
3723 mutex_unlock(&mdsc->mutex);
3724
3725 ceph_cleanup_empty_realms(mdsc);
3726
3727 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3728
3729 dout("stopped\n");
3730 }
3731
3732 void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc)
3733 {
3734 struct ceph_mds_session *session;
3735 int mds;
3736
3737 dout("force umount\n");
3738
3739 mutex_lock(&mdsc->mutex);
3740 for (mds = 0; mds < mdsc->max_sessions; mds++) {
3741 session = __ceph_lookup_mds_session(mdsc, mds);
3742 if (!session)
3743 continue;
3744 mutex_unlock(&mdsc->mutex);
3745 mutex_lock(&session->s_mutex);
3746 __close_session(mdsc, session);
3747 if (session->s_state == CEPH_MDS_SESSION_CLOSING) {
3748 cleanup_session_requests(mdsc, session);
3749 remove_session_caps(session);
3750 }
3751 mutex_unlock(&session->s_mutex);
3752 ceph_put_mds_session(session);
3753 mutex_lock(&mdsc->mutex);
3754 kick_requests(mdsc, mds);
3755 }
3756 __wake_requests(mdsc, &mdsc->waiting_for_map);
3757 mutex_unlock(&mdsc->mutex);
3758 }
3759
3760 static void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
3761 {
3762 dout("stop\n");
3763 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3764 if (mdsc->mdsmap)
3765 ceph_mdsmap_destroy(mdsc->mdsmap);
3766 kfree(mdsc->sessions);
3767 ceph_caps_finalize(mdsc);
3768 ceph_pool_perm_destroy(mdsc);
3769 }
3770
3771 void ceph_mdsc_destroy(struct ceph_fs_client *fsc)
3772 {
3773 struct ceph_mds_client *mdsc = fsc->mdsc;
3774
3775 dout("mdsc_destroy %p\n", mdsc);
3776 ceph_mdsc_stop(mdsc);
3777
3778 /* flush out any connection work with references to us */
3779 ceph_msgr_flush();
3780
3781 fsc->mdsc = NULL;
3782 kfree(mdsc);
3783 dout("mdsc_destroy %p done\n", mdsc);
3784 }
3785
3786 void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3787 {
3788 struct ceph_fs_client *fsc = mdsc->fsc;
3789 const char *mds_namespace = fsc->mount_options->mds_namespace;
3790 void *p = msg->front.iov_base;
3791 void *end = p + msg->front.iov_len;
3792 u32 epoch;
3793 u32 map_len;
3794 u32 num_fs;
3795 u32 mount_fscid = (u32)-1;
3796 u8 struct_v, struct_cv;
3797 int err = -EINVAL;
3798
3799 ceph_decode_need(&p, end, sizeof(u32), bad);
3800 epoch = ceph_decode_32(&p);
3801
3802 dout("handle_fsmap epoch %u\n", epoch);
3803
3804 ceph_decode_need(&p, end, 2 + sizeof(u32), bad);
3805 struct_v = ceph_decode_8(&p);
3806 struct_cv = ceph_decode_8(&p);
3807 map_len = ceph_decode_32(&p);
3808
3809 ceph_decode_need(&p, end, sizeof(u32) * 3, bad);
3810 p += sizeof(u32) * 2; /* skip epoch and legacy_client_fscid */
3811
3812 num_fs = ceph_decode_32(&p);
3813 while (num_fs-- > 0) {
3814 void *info_p, *info_end;
3815 u32 info_len;
3816 u8 info_v, info_cv;
3817 u32 fscid, namelen;
3818
3819 ceph_decode_need(&p, end, 2 + sizeof(u32), bad);
3820 info_v = ceph_decode_8(&p);
3821 info_cv = ceph_decode_8(&p);
3822 info_len = ceph_decode_32(&p);
3823 ceph_decode_need(&p, end, info_len, bad);
3824 info_p = p;
3825 info_end = p + info_len;
3826 p = info_end;
3827
3828 ceph_decode_need(&info_p, info_end, sizeof(u32) * 2, bad);
3829 fscid = ceph_decode_32(&info_p);
3830 namelen = ceph_decode_32(&info_p);
3831 ceph_decode_need(&info_p, info_end, namelen, bad);
3832
3833 if (mds_namespace &&
3834 strlen(mds_namespace) == namelen &&
3835 !strncmp(mds_namespace, (char *)info_p, namelen)) {
3836 mount_fscid = fscid;
3837 break;
3838 }
3839 }
3840
3841 ceph_monc_got_map(&fsc->client->monc, CEPH_SUB_FSMAP, epoch);
3842 if (mount_fscid != (u32)-1) {
3843 fsc->client->monc.fs_cluster_id = mount_fscid;
3844 ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
3845 0, true);
3846 ceph_monc_renew_subs(&fsc->client->monc);
3847 } else {
3848 err = -ENOENT;
3849 goto err_out;
3850 }
3851 return;
3852 bad:
3853 pr_err("error decoding fsmap\n");
3854 err_out:
3855 mutex_lock(&mdsc->mutex);
3856 mdsc->mdsmap_err = -ENOENT;
3857 __wake_requests(mdsc, &mdsc->waiting_for_map);
3858 mutex_unlock(&mdsc->mutex);
3859 return;
3860 }
3861
3862 /*
3863 * handle mds map update.
3864 */
3865 void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3866 {
3867 u32 epoch;
3868 u32 maplen;
3869 void *p = msg->front.iov_base;
3870 void *end = p + msg->front.iov_len;
3871 struct ceph_mdsmap *newmap, *oldmap;
3872 struct ceph_fsid fsid;
3873 int err = -EINVAL;
3874
3875 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
3876 ceph_decode_copy(&p, &fsid, sizeof(fsid));
3877 if (ceph_check_fsid(mdsc->fsc->client, &fsid) < 0)
3878 return;
3879 epoch = ceph_decode_32(&p);
3880 maplen = ceph_decode_32(&p);
3881 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
3882
3883 /* do we need it? */
3884 mutex_lock(&mdsc->mutex);
3885 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
3886 dout("handle_map epoch %u <= our %u\n",
3887 epoch, mdsc->mdsmap->m_epoch);
3888 mutex_unlock(&mdsc->mutex);
3889 return;
3890 }
3891
3892 newmap = ceph_mdsmap_decode(&p, end);
3893 if (IS_ERR(newmap)) {
3894 err = PTR_ERR(newmap);
3895 goto bad_unlock;
3896 }
3897
3898 /* swap into place */
3899 if (mdsc->mdsmap) {
3900 oldmap = mdsc->mdsmap;
3901 mdsc->mdsmap = newmap;
3902 check_new_map(mdsc, newmap, oldmap);
3903 ceph_mdsmap_destroy(oldmap);
3904 } else {
3905 mdsc->mdsmap = newmap; /* first mds map */
3906 }
3907 mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
3908
3909 __wake_requests(mdsc, &mdsc->waiting_for_map);
3910 ceph_monc_got_map(&mdsc->fsc->client->monc, CEPH_SUB_MDSMAP,
3911 mdsc->mdsmap->m_epoch);
3912
3913 mutex_unlock(&mdsc->mutex);
3914 schedule_delayed(mdsc);
3915 return;
3916
3917 bad_unlock:
3918 mutex_unlock(&mdsc->mutex);
3919 bad:
3920 pr_err("error decoding mdsmap %d\n", err);
3921 return;
3922 }
3923
3924 static struct ceph_connection *con_get(struct ceph_connection *con)
3925 {
3926 struct ceph_mds_session *s = con->private;
3927
3928 if (get_session(s)) {
3929 dout("mdsc con_get %p ok (%d)\n", s, refcount_read(&s->s_ref));
3930 return con;
3931 }
3932 dout("mdsc con_get %p FAIL\n", s);
3933 return NULL;
3934 }
3935
3936 static void con_put(struct ceph_connection *con)
3937 {
3938 struct ceph_mds_session *s = con->private;
3939
3940 dout("mdsc con_put %p (%d)\n", s, refcount_read(&s->s_ref) - 1);
3941 ceph_put_mds_session(s);
3942 }
3943
3944 /*
3945 * if the client is unresponsive for long enough, the mds will kill
3946 * the session entirely.
3947 */
3948 static void peer_reset(struct ceph_connection *con)
3949 {
3950 struct ceph_mds_session *s = con->private;
3951 struct ceph_mds_client *mdsc = s->s_mdsc;
3952
3953 pr_warn("mds%d closed our session\n", s->s_mds);
3954 send_mds_reconnect(mdsc, s);
3955 }
3956
3957 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
3958 {
3959 struct ceph_mds_session *s = con->private;
3960 struct ceph_mds_client *mdsc = s->s_mdsc;
3961 int type = le16_to_cpu(msg->hdr.type);
3962
3963 mutex_lock(&mdsc->mutex);
3964 if (__verify_registered_session(mdsc, s) < 0) {
3965 mutex_unlock(&mdsc->mutex);
3966 goto out;
3967 }
3968 mutex_unlock(&mdsc->mutex);
3969
3970 switch (type) {
3971 case CEPH_MSG_MDS_MAP:
3972 ceph_mdsc_handle_mdsmap(mdsc, msg);
3973 break;
3974 case CEPH_MSG_FS_MAP_USER:
3975 ceph_mdsc_handle_fsmap(mdsc, msg);
3976 break;
3977 case CEPH_MSG_CLIENT_SESSION:
3978 handle_session(s, msg);
3979 break;
3980 case CEPH_MSG_CLIENT_REPLY:
3981 handle_reply(s, msg);
3982 break;
3983 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
3984 handle_forward(mdsc, s, msg);
3985 break;
3986 case CEPH_MSG_CLIENT_CAPS:
3987 ceph_handle_caps(s, msg);
3988 break;
3989 case CEPH_MSG_CLIENT_SNAP:
3990 ceph_handle_snap(mdsc, s, msg);
3991 break;
3992 case CEPH_MSG_CLIENT_LEASE:
3993 handle_lease(mdsc, s, msg);
3994 break;
3995
3996 default:
3997 pr_err("received unknown message type %d %s\n", type,
3998 ceph_msg_type_name(type));
3999 }
4000 out:
4001 ceph_msg_put(msg);
4002 }
4003
4004 /*
4005 * authentication
4006 */
4007
4008 /*
4009 * Note: returned pointer is the address of a structure that's
4010 * managed separately. Caller must *not* attempt to free it.
4011 */
4012 static struct ceph_auth_handshake *get_authorizer(struct ceph_connection *con,
4013 int *proto, int force_new)
4014 {
4015 struct ceph_mds_session *s = con->private;
4016 struct ceph_mds_client *mdsc = s->s_mdsc;
4017 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
4018 struct ceph_auth_handshake *auth = &s->s_auth;
4019
4020 if (force_new && auth->authorizer) {
4021 ceph_auth_destroy_authorizer(auth->authorizer);
4022 auth->authorizer = NULL;
4023 }
4024 if (!auth->authorizer) {
4025 int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
4026 auth);
4027 if (ret)
4028 return ERR_PTR(ret);
4029 } else {
4030 int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
4031 auth);
4032 if (ret)
4033 return ERR_PTR(ret);
4034 }
4035 *proto = ac->protocol;
4036
4037 return auth;
4038 }
4039
4040
4041 static int verify_authorizer_reply(struct ceph_connection *con)
4042 {
4043 struct ceph_mds_session *s = con->private;
4044 struct ceph_mds_client *mdsc = s->s_mdsc;
4045 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
4046
4047 return ceph_auth_verify_authorizer_reply(ac, s->s_auth.authorizer);
4048 }
4049
4050 static int invalidate_authorizer(struct ceph_connection *con)
4051 {
4052 struct ceph_mds_session *s = con->private;
4053 struct ceph_mds_client *mdsc = s->s_mdsc;
4054 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
4055
4056 ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
4057
4058 return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
4059 }
4060
4061 static struct ceph_msg *mds_alloc_msg(struct ceph_connection *con,
4062 struct ceph_msg_header *hdr, int *skip)
4063 {
4064 struct ceph_msg *msg;
4065 int type = (int) le16_to_cpu(hdr->type);
4066 int front_len = (int) le32_to_cpu(hdr->front_len);
4067
4068 if (con->in_msg)
4069 return con->in_msg;
4070
4071 *skip = 0;
4072 msg = ceph_msg_new(type, front_len, GFP_NOFS, false);
4073 if (!msg) {
4074 pr_err("unable to allocate msg type %d len %d\n",
4075 type, front_len);
4076 return NULL;
4077 }
4078
4079 return msg;
4080 }
4081
4082 static int mds_sign_message(struct ceph_msg *msg)
4083 {
4084 struct ceph_mds_session *s = msg->con->private;
4085 struct ceph_auth_handshake *auth = &s->s_auth;
4086
4087 return ceph_auth_sign_message(auth, msg);
4088 }
4089
4090 static int mds_check_message_signature(struct ceph_msg *msg)
4091 {
4092 struct ceph_mds_session *s = msg->con->private;
4093 struct ceph_auth_handshake *auth = &s->s_auth;
4094
4095 return ceph_auth_check_message_signature(auth, msg);
4096 }
4097
4098 static const struct ceph_connection_operations mds_con_ops = {
4099 .get = con_get,
4100 .put = con_put,
4101 .dispatch = dispatch,
4102 .get_authorizer = get_authorizer,
4103 .verify_authorizer_reply = verify_authorizer_reply,
4104 .invalidate_authorizer = invalidate_authorizer,
4105 .peer_reset = peer_reset,
4106 .alloc_msg = mds_alloc_msg,
4107 .sign_message = mds_sign_message,
4108 .check_message_signature = mds_check_message_signature,
4109 };
4110
4111 /* eof */
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