The discovered bit in PGCCSR register indicates if the device has been
[linux-2.6/next.git] / fs / ceph / mds_client.c
blob2712e8ff34d1f8ae72fd988d3ebb0cd05f435012
1 #include <linux/ceph/ceph_debug.h>
3 #include <linux/fs.h>
4 #include <linux/wait.h>
5 #include <linux/slab.h>
6 #include <linux/sched.h>
7 #include <linux/debugfs.h>
8 #include <linux/seq_file.h>
10 #include "super.h"
11 #include "mds_client.h"
13 #include <linux/ceph/messenger.h>
14 #include <linux/ceph/decode.h>
15 #include <linux/ceph/pagelist.h>
16 #include <linux/ceph/auth.h>
17 #include <linux/ceph/debugfs.h>
20 * A cluster of MDS (metadata server) daemons is responsible for
21 * managing the file system namespace (the directory hierarchy and
22 * inodes) and for coordinating shared access to storage. Metadata is
23 * partitioning hierarchically across a number of servers, and that
24 * partition varies over time as the cluster adjusts the distribution
25 * in order to balance load.
27 * The MDS client is primarily responsible to managing synchronous
28 * metadata requests for operations like open, unlink, and so forth.
29 * If there is a MDS failure, we find out about it when we (possibly
30 * request and) receive a new MDS map, and can resubmit affected
31 * requests.
33 * For the most part, though, we take advantage of a lossless
34 * communications channel to the MDS, and do not need to worry about
35 * timing out or resubmitting requests.
37 * We maintain a stateful "session" with each MDS we interact with.
38 * Within each session, we sent periodic heartbeat messages to ensure
39 * any capabilities or leases we have been issues remain valid. If
40 * the session times out and goes stale, our leases and capabilities
41 * are no longer valid.
44 struct ceph_reconnect_state {
45 struct ceph_pagelist *pagelist;
46 bool flock;
49 static void __wake_requests(struct ceph_mds_client *mdsc,
50 struct list_head *head);
52 static const struct ceph_connection_operations mds_con_ops;
56 * mds reply parsing
60 * parse individual inode info
62 static int parse_reply_info_in(void **p, void *end,
63 struct ceph_mds_reply_info_in *info,
64 int features)
66 int err = -EIO;
68 info->in = *p;
69 *p += sizeof(struct ceph_mds_reply_inode) +
70 sizeof(*info->in->fragtree.splits) *
71 le32_to_cpu(info->in->fragtree.nsplits);
73 ceph_decode_32_safe(p, end, info->symlink_len, bad);
74 ceph_decode_need(p, end, info->symlink_len, bad);
75 info->symlink = *p;
76 *p += info->symlink_len;
78 if (features & CEPH_FEATURE_DIRLAYOUTHASH)
79 ceph_decode_copy_safe(p, end, &info->dir_layout,
80 sizeof(info->dir_layout), bad);
81 else
82 memset(&info->dir_layout, 0, sizeof(info->dir_layout));
84 ceph_decode_32_safe(p, end, info->xattr_len, bad);
85 ceph_decode_need(p, end, info->xattr_len, bad);
86 info->xattr_data = *p;
87 *p += info->xattr_len;
88 return 0;
89 bad:
90 return err;
94 * parse a normal reply, which may contain a (dir+)dentry and/or a
95 * target inode.
97 static int parse_reply_info_trace(void **p, void *end,
98 struct ceph_mds_reply_info_parsed *info,
99 int features)
101 int err;
103 if (info->head->is_dentry) {
104 err = parse_reply_info_in(p, end, &info->diri, features);
105 if (err < 0)
106 goto out_bad;
108 if (unlikely(*p + sizeof(*info->dirfrag) > end))
109 goto bad;
110 info->dirfrag = *p;
111 *p += sizeof(*info->dirfrag) +
112 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
113 if (unlikely(*p > end))
114 goto bad;
116 ceph_decode_32_safe(p, end, info->dname_len, bad);
117 ceph_decode_need(p, end, info->dname_len, bad);
118 info->dname = *p;
119 *p += info->dname_len;
120 info->dlease = *p;
121 *p += sizeof(*info->dlease);
124 if (info->head->is_target) {
125 err = parse_reply_info_in(p, end, &info->targeti, features);
126 if (err < 0)
127 goto out_bad;
130 if (unlikely(*p != end))
131 goto bad;
132 return 0;
134 bad:
135 err = -EIO;
136 out_bad:
137 pr_err("problem parsing mds trace %d\n", err);
138 return err;
142 * parse readdir results
144 static int parse_reply_info_dir(void **p, void *end,
145 struct ceph_mds_reply_info_parsed *info,
146 int features)
148 u32 num, i = 0;
149 int err;
151 info->dir_dir = *p;
152 if (*p + sizeof(*info->dir_dir) > end)
153 goto bad;
154 *p += sizeof(*info->dir_dir) +
155 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
156 if (*p > end)
157 goto bad;
159 ceph_decode_need(p, end, sizeof(num) + 2, bad);
160 num = ceph_decode_32(p);
161 info->dir_end = ceph_decode_8(p);
162 info->dir_complete = ceph_decode_8(p);
163 if (num == 0)
164 goto done;
166 /* alloc large array */
167 info->dir_nr = num;
168 info->dir_in = kcalloc(num, sizeof(*info->dir_in) +
169 sizeof(*info->dir_dname) +
170 sizeof(*info->dir_dname_len) +
171 sizeof(*info->dir_dlease),
172 GFP_NOFS);
173 if (info->dir_in == NULL) {
174 err = -ENOMEM;
175 goto out_bad;
177 info->dir_dname = (void *)(info->dir_in + num);
178 info->dir_dname_len = (void *)(info->dir_dname + num);
179 info->dir_dlease = (void *)(info->dir_dname_len + num);
181 while (num) {
182 /* dentry */
183 ceph_decode_need(p, end, sizeof(u32)*2, bad);
184 info->dir_dname_len[i] = ceph_decode_32(p);
185 ceph_decode_need(p, end, info->dir_dname_len[i], bad);
186 info->dir_dname[i] = *p;
187 *p += info->dir_dname_len[i];
188 dout("parsed dir dname '%.*s'\n", info->dir_dname_len[i],
189 info->dir_dname[i]);
190 info->dir_dlease[i] = *p;
191 *p += sizeof(struct ceph_mds_reply_lease);
193 /* inode */
194 err = parse_reply_info_in(p, end, &info->dir_in[i], features);
195 if (err < 0)
196 goto out_bad;
197 i++;
198 num--;
201 done:
202 if (*p != end)
203 goto bad;
204 return 0;
206 bad:
207 err = -EIO;
208 out_bad:
209 pr_err("problem parsing dir contents %d\n", err);
210 return err;
214 * parse fcntl F_GETLK results
216 static int parse_reply_info_filelock(void **p, void *end,
217 struct ceph_mds_reply_info_parsed *info,
218 int features)
220 if (*p + sizeof(*info->filelock_reply) > end)
221 goto bad;
223 info->filelock_reply = *p;
224 *p += sizeof(*info->filelock_reply);
226 if (unlikely(*p != end))
227 goto bad;
228 return 0;
230 bad:
231 return -EIO;
235 * parse extra results
237 static int parse_reply_info_extra(void **p, void *end,
238 struct ceph_mds_reply_info_parsed *info,
239 int features)
241 if (info->head->op == CEPH_MDS_OP_GETFILELOCK)
242 return parse_reply_info_filelock(p, end, info, features);
243 else
244 return parse_reply_info_dir(p, end, info, features);
248 * parse entire mds reply
250 static int parse_reply_info(struct ceph_msg *msg,
251 struct ceph_mds_reply_info_parsed *info,
252 int features)
254 void *p, *end;
255 u32 len;
256 int err;
258 info->head = msg->front.iov_base;
259 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
260 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
262 /* trace */
263 ceph_decode_32_safe(&p, end, len, bad);
264 if (len > 0) {
265 err = parse_reply_info_trace(&p, p+len, info, features);
266 if (err < 0)
267 goto out_bad;
270 /* extra */
271 ceph_decode_32_safe(&p, end, len, bad);
272 if (len > 0) {
273 err = parse_reply_info_extra(&p, p+len, info, features);
274 if (err < 0)
275 goto out_bad;
278 /* snap blob */
279 ceph_decode_32_safe(&p, end, len, bad);
280 info->snapblob_len = len;
281 info->snapblob = p;
282 p += len;
284 if (p != end)
285 goto bad;
286 return 0;
288 bad:
289 err = -EIO;
290 out_bad:
291 pr_err("mds parse_reply err %d\n", err);
292 return err;
295 static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
297 kfree(info->dir_in);
302 * sessions
304 static const char *session_state_name(int s)
306 switch (s) {
307 case CEPH_MDS_SESSION_NEW: return "new";
308 case CEPH_MDS_SESSION_OPENING: return "opening";
309 case CEPH_MDS_SESSION_OPEN: return "open";
310 case CEPH_MDS_SESSION_HUNG: return "hung";
311 case CEPH_MDS_SESSION_CLOSING: return "closing";
312 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
313 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
314 default: return "???";
318 static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
320 if (atomic_inc_not_zero(&s->s_ref)) {
321 dout("mdsc get_session %p %d -> %d\n", s,
322 atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
323 return s;
324 } else {
325 dout("mdsc get_session %p 0 -- FAIL", s);
326 return NULL;
330 void ceph_put_mds_session(struct ceph_mds_session *s)
332 dout("mdsc put_session %p %d -> %d\n", s,
333 atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
334 if (atomic_dec_and_test(&s->s_ref)) {
335 if (s->s_authorizer)
336 s->s_mdsc->fsc->client->monc.auth->ops->destroy_authorizer(
337 s->s_mdsc->fsc->client->monc.auth,
338 s->s_authorizer);
339 kfree(s);
344 * called under mdsc->mutex
346 struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
347 int mds)
349 struct ceph_mds_session *session;
351 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
352 return NULL;
353 session = mdsc->sessions[mds];
354 dout("lookup_mds_session %p %d\n", session,
355 atomic_read(&session->s_ref));
356 get_session(session);
357 return session;
360 static bool __have_session(struct ceph_mds_client *mdsc, int mds)
362 if (mds >= mdsc->max_sessions)
363 return false;
364 return mdsc->sessions[mds];
367 static int __verify_registered_session(struct ceph_mds_client *mdsc,
368 struct ceph_mds_session *s)
370 if (s->s_mds >= mdsc->max_sessions ||
371 mdsc->sessions[s->s_mds] != s)
372 return -ENOENT;
373 return 0;
377 * create+register a new session for given mds.
378 * called under mdsc->mutex.
380 static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
381 int mds)
383 struct ceph_mds_session *s;
385 s = kzalloc(sizeof(*s), GFP_NOFS);
386 if (!s)
387 return ERR_PTR(-ENOMEM);
388 s->s_mdsc = mdsc;
389 s->s_mds = mds;
390 s->s_state = CEPH_MDS_SESSION_NEW;
391 s->s_ttl = 0;
392 s->s_seq = 0;
393 mutex_init(&s->s_mutex);
395 ceph_con_init(mdsc->fsc->client->msgr, &s->s_con);
396 s->s_con.private = s;
397 s->s_con.ops = &mds_con_ops;
398 s->s_con.peer_name.type = CEPH_ENTITY_TYPE_MDS;
399 s->s_con.peer_name.num = cpu_to_le64(mds);
401 spin_lock_init(&s->s_cap_lock);
402 s->s_cap_gen = 0;
403 s->s_cap_ttl = 0;
404 s->s_renew_requested = 0;
405 s->s_renew_seq = 0;
406 INIT_LIST_HEAD(&s->s_caps);
407 s->s_nr_caps = 0;
408 s->s_trim_caps = 0;
409 atomic_set(&s->s_ref, 1);
410 INIT_LIST_HEAD(&s->s_waiting);
411 INIT_LIST_HEAD(&s->s_unsafe);
412 s->s_num_cap_releases = 0;
413 s->s_cap_iterator = NULL;
414 INIT_LIST_HEAD(&s->s_cap_releases);
415 INIT_LIST_HEAD(&s->s_cap_releases_done);
416 INIT_LIST_HEAD(&s->s_cap_flushing);
417 INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
419 dout("register_session mds%d\n", mds);
420 if (mds >= mdsc->max_sessions) {
421 int newmax = 1 << get_count_order(mds+1);
422 struct ceph_mds_session **sa;
424 dout("register_session realloc to %d\n", newmax);
425 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
426 if (sa == NULL)
427 goto fail_realloc;
428 if (mdsc->sessions) {
429 memcpy(sa, mdsc->sessions,
430 mdsc->max_sessions * sizeof(void *));
431 kfree(mdsc->sessions);
433 mdsc->sessions = sa;
434 mdsc->max_sessions = newmax;
436 mdsc->sessions[mds] = s;
437 atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
439 ceph_con_open(&s->s_con, ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
441 return s;
443 fail_realloc:
444 kfree(s);
445 return ERR_PTR(-ENOMEM);
449 * called under mdsc->mutex
451 static void __unregister_session(struct ceph_mds_client *mdsc,
452 struct ceph_mds_session *s)
454 dout("__unregister_session mds%d %p\n", s->s_mds, s);
455 BUG_ON(mdsc->sessions[s->s_mds] != s);
456 mdsc->sessions[s->s_mds] = NULL;
457 ceph_con_close(&s->s_con);
458 ceph_put_mds_session(s);
462 * drop session refs in request.
464 * should be last request ref, or hold mdsc->mutex
466 static void put_request_session(struct ceph_mds_request *req)
468 if (req->r_session) {
469 ceph_put_mds_session(req->r_session);
470 req->r_session = NULL;
474 void ceph_mdsc_release_request(struct kref *kref)
476 struct ceph_mds_request *req = container_of(kref,
477 struct ceph_mds_request,
478 r_kref);
479 if (req->r_request)
480 ceph_msg_put(req->r_request);
481 if (req->r_reply) {
482 ceph_msg_put(req->r_reply);
483 destroy_reply_info(&req->r_reply_info);
485 if (req->r_inode) {
486 ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
487 iput(req->r_inode);
489 if (req->r_locked_dir)
490 ceph_put_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
491 if (req->r_target_inode)
492 iput(req->r_target_inode);
493 if (req->r_dentry)
494 dput(req->r_dentry);
495 if (req->r_old_dentry) {
497 * track (and drop pins for) r_old_dentry_dir
498 * separately, since r_old_dentry's d_parent may have
499 * changed between the dir mutex being dropped and
500 * this request being freed.
502 ceph_put_cap_refs(ceph_inode(req->r_old_dentry_dir),
503 CEPH_CAP_PIN);
504 dput(req->r_old_dentry);
505 iput(req->r_old_dentry_dir);
507 kfree(req->r_path1);
508 kfree(req->r_path2);
509 put_request_session(req);
510 ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation);
511 kfree(req);
515 * lookup session, bump ref if found.
517 * called under mdsc->mutex.
519 static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
520 u64 tid)
522 struct ceph_mds_request *req;
523 struct rb_node *n = mdsc->request_tree.rb_node;
525 while (n) {
526 req = rb_entry(n, struct ceph_mds_request, r_node);
527 if (tid < req->r_tid)
528 n = n->rb_left;
529 else if (tid > req->r_tid)
530 n = n->rb_right;
531 else {
532 ceph_mdsc_get_request(req);
533 return req;
536 return NULL;
539 static void __insert_request(struct ceph_mds_client *mdsc,
540 struct ceph_mds_request *new)
542 struct rb_node **p = &mdsc->request_tree.rb_node;
543 struct rb_node *parent = NULL;
544 struct ceph_mds_request *req = NULL;
546 while (*p) {
547 parent = *p;
548 req = rb_entry(parent, struct ceph_mds_request, r_node);
549 if (new->r_tid < req->r_tid)
550 p = &(*p)->rb_left;
551 else if (new->r_tid > req->r_tid)
552 p = &(*p)->rb_right;
553 else
554 BUG();
557 rb_link_node(&new->r_node, parent, p);
558 rb_insert_color(&new->r_node, &mdsc->request_tree);
562 * Register an in-flight request, and assign a tid. Link to directory
563 * are modifying (if any).
565 * Called under mdsc->mutex.
567 static void __register_request(struct ceph_mds_client *mdsc,
568 struct ceph_mds_request *req,
569 struct inode *dir)
571 req->r_tid = ++mdsc->last_tid;
572 if (req->r_num_caps)
573 ceph_reserve_caps(mdsc, &req->r_caps_reservation,
574 req->r_num_caps);
575 dout("__register_request %p tid %lld\n", req, req->r_tid);
576 ceph_mdsc_get_request(req);
577 __insert_request(mdsc, req);
579 req->r_uid = current_fsuid();
580 req->r_gid = current_fsgid();
582 if (dir) {
583 struct ceph_inode_info *ci = ceph_inode(dir);
585 ihold(dir);
586 spin_lock(&ci->i_unsafe_lock);
587 req->r_unsafe_dir = dir;
588 list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
589 spin_unlock(&ci->i_unsafe_lock);
593 static void __unregister_request(struct ceph_mds_client *mdsc,
594 struct ceph_mds_request *req)
596 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
597 rb_erase(&req->r_node, &mdsc->request_tree);
598 RB_CLEAR_NODE(&req->r_node);
600 if (req->r_unsafe_dir) {
601 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
603 spin_lock(&ci->i_unsafe_lock);
604 list_del_init(&req->r_unsafe_dir_item);
605 spin_unlock(&ci->i_unsafe_lock);
607 iput(req->r_unsafe_dir);
608 req->r_unsafe_dir = NULL;
611 ceph_mdsc_put_request(req);
615 * Choose mds to send request to next. If there is a hint set in the
616 * request (e.g., due to a prior forward hint from the mds), use that.
617 * Otherwise, consult frag tree and/or caps to identify the
618 * appropriate mds. If all else fails, choose randomly.
620 * Called under mdsc->mutex.
622 struct dentry *get_nonsnap_parent(struct dentry *dentry)
625 * we don't need to worry about protecting the d_parent access
626 * here because we never renaming inside the snapped namespace
627 * except to resplice to another snapdir, and either the old or new
628 * result is a valid result.
630 while (!IS_ROOT(dentry) && ceph_snap(dentry->d_inode) != CEPH_NOSNAP)
631 dentry = dentry->d_parent;
632 return dentry;
635 static int __choose_mds(struct ceph_mds_client *mdsc,
636 struct ceph_mds_request *req)
638 struct inode *inode;
639 struct ceph_inode_info *ci;
640 struct ceph_cap *cap;
641 int mode = req->r_direct_mode;
642 int mds = -1;
643 u32 hash = req->r_direct_hash;
644 bool is_hash = req->r_direct_is_hash;
647 * is there a specific mds we should try? ignore hint if we have
648 * no session and the mds is not up (active or recovering).
650 if (req->r_resend_mds >= 0 &&
651 (__have_session(mdsc, req->r_resend_mds) ||
652 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
653 dout("choose_mds using resend_mds mds%d\n",
654 req->r_resend_mds);
655 return req->r_resend_mds;
658 if (mode == USE_RANDOM_MDS)
659 goto random;
661 inode = NULL;
662 if (req->r_inode) {
663 inode = req->r_inode;
664 } else if (req->r_dentry) {
665 /* ignore race with rename; old or new d_parent is okay */
666 struct dentry *parent = req->r_dentry->d_parent;
667 struct inode *dir = parent->d_inode;
669 if (dir->i_sb != mdsc->fsc->sb) {
670 /* not this fs! */
671 inode = req->r_dentry->d_inode;
672 } else if (ceph_snap(dir) != CEPH_NOSNAP) {
673 /* direct snapped/virtual snapdir requests
674 * based on parent dir inode */
675 struct dentry *dn = get_nonsnap_parent(parent);
676 inode = dn->d_inode;
677 dout("__choose_mds using nonsnap parent %p\n", inode);
678 } else if (req->r_dentry->d_inode) {
679 /* dentry target */
680 inode = req->r_dentry->d_inode;
681 } else {
682 /* dir + name */
683 inode = dir;
684 hash = ceph_dentry_hash(dir, req->r_dentry);
685 is_hash = true;
689 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
690 (int)hash, mode);
691 if (!inode)
692 goto random;
693 ci = ceph_inode(inode);
695 if (is_hash && S_ISDIR(inode->i_mode)) {
696 struct ceph_inode_frag frag;
697 int found;
699 ceph_choose_frag(ci, hash, &frag, &found);
700 if (found) {
701 if (mode == USE_ANY_MDS && frag.ndist > 0) {
702 u8 r;
704 /* choose a random replica */
705 get_random_bytes(&r, 1);
706 r %= frag.ndist;
707 mds = frag.dist[r];
708 dout("choose_mds %p %llx.%llx "
709 "frag %u mds%d (%d/%d)\n",
710 inode, ceph_vinop(inode),
711 frag.frag, mds,
712 (int)r, frag.ndist);
713 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
714 CEPH_MDS_STATE_ACTIVE)
715 return mds;
718 /* since this file/dir wasn't known to be
719 * replicated, then we want to look for the
720 * authoritative mds. */
721 mode = USE_AUTH_MDS;
722 if (frag.mds >= 0) {
723 /* choose auth mds */
724 mds = frag.mds;
725 dout("choose_mds %p %llx.%llx "
726 "frag %u mds%d (auth)\n",
727 inode, ceph_vinop(inode), frag.frag, mds);
728 if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >=
729 CEPH_MDS_STATE_ACTIVE)
730 return mds;
735 spin_lock(&inode->i_lock);
736 cap = NULL;
737 if (mode == USE_AUTH_MDS)
738 cap = ci->i_auth_cap;
739 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
740 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
741 if (!cap) {
742 spin_unlock(&inode->i_lock);
743 goto random;
745 mds = cap->session->s_mds;
746 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
747 inode, ceph_vinop(inode), mds,
748 cap == ci->i_auth_cap ? "auth " : "", cap);
749 spin_unlock(&inode->i_lock);
750 return mds;
752 random:
753 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
754 dout("choose_mds chose random mds%d\n", mds);
755 return mds;
760 * session messages
762 static struct ceph_msg *create_session_msg(u32 op, u64 seq)
764 struct ceph_msg *msg;
765 struct ceph_mds_session_head *h;
767 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), GFP_NOFS,
768 false);
769 if (!msg) {
770 pr_err("create_session_msg ENOMEM creating msg\n");
771 return NULL;
773 h = msg->front.iov_base;
774 h->op = cpu_to_le32(op);
775 h->seq = cpu_to_le64(seq);
776 return msg;
780 * send session open request.
782 * called under mdsc->mutex
784 static int __open_session(struct ceph_mds_client *mdsc,
785 struct ceph_mds_session *session)
787 struct ceph_msg *msg;
788 int mstate;
789 int mds = session->s_mds;
791 /* wait for mds to go active? */
792 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
793 dout("open_session to mds%d (%s)\n", mds,
794 ceph_mds_state_name(mstate));
795 session->s_state = CEPH_MDS_SESSION_OPENING;
796 session->s_renew_requested = jiffies;
798 /* send connect message */
799 msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
800 if (!msg)
801 return -ENOMEM;
802 ceph_con_send(&session->s_con, msg);
803 return 0;
807 * open sessions for any export targets for the given mds
809 * called under mdsc->mutex
811 static void __open_export_target_sessions(struct ceph_mds_client *mdsc,
812 struct ceph_mds_session *session)
814 struct ceph_mds_info *mi;
815 struct ceph_mds_session *ts;
816 int i, mds = session->s_mds;
817 int target;
819 if (mds >= mdsc->mdsmap->m_max_mds)
820 return;
821 mi = &mdsc->mdsmap->m_info[mds];
822 dout("open_export_target_sessions for mds%d (%d targets)\n",
823 session->s_mds, mi->num_export_targets);
825 for (i = 0; i < mi->num_export_targets; i++) {
826 target = mi->export_targets[i];
827 ts = __ceph_lookup_mds_session(mdsc, target);
828 if (!ts) {
829 ts = register_session(mdsc, target);
830 if (IS_ERR(ts))
831 return;
833 if (session->s_state == CEPH_MDS_SESSION_NEW ||
834 session->s_state == CEPH_MDS_SESSION_CLOSING)
835 __open_session(mdsc, session);
836 else
837 dout(" mds%d target mds%d %p is %s\n", session->s_mds,
838 i, ts, session_state_name(ts->s_state));
839 ceph_put_mds_session(ts);
843 void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
844 struct ceph_mds_session *session)
846 mutex_lock(&mdsc->mutex);
847 __open_export_target_sessions(mdsc, session);
848 mutex_unlock(&mdsc->mutex);
852 * session caps
856 * Free preallocated cap messages assigned to this session
858 static void cleanup_cap_releases(struct ceph_mds_session *session)
860 struct ceph_msg *msg;
862 spin_lock(&session->s_cap_lock);
863 while (!list_empty(&session->s_cap_releases)) {
864 msg = list_first_entry(&session->s_cap_releases,
865 struct ceph_msg, list_head);
866 list_del_init(&msg->list_head);
867 ceph_msg_put(msg);
869 while (!list_empty(&session->s_cap_releases_done)) {
870 msg = list_first_entry(&session->s_cap_releases_done,
871 struct ceph_msg, list_head);
872 list_del_init(&msg->list_head);
873 ceph_msg_put(msg);
875 spin_unlock(&session->s_cap_lock);
879 * Helper to safely iterate over all caps associated with a session, with
880 * special care taken to handle a racing __ceph_remove_cap().
882 * Caller must hold session s_mutex.
884 static int iterate_session_caps(struct ceph_mds_session *session,
885 int (*cb)(struct inode *, struct ceph_cap *,
886 void *), void *arg)
888 struct list_head *p;
889 struct ceph_cap *cap;
890 struct inode *inode, *last_inode = NULL;
891 struct ceph_cap *old_cap = NULL;
892 int ret;
894 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
895 spin_lock(&session->s_cap_lock);
896 p = session->s_caps.next;
897 while (p != &session->s_caps) {
898 cap = list_entry(p, struct ceph_cap, session_caps);
899 inode = igrab(&cap->ci->vfs_inode);
900 if (!inode) {
901 p = p->next;
902 continue;
904 session->s_cap_iterator = cap;
905 spin_unlock(&session->s_cap_lock);
907 if (last_inode) {
908 iput(last_inode);
909 last_inode = NULL;
911 if (old_cap) {
912 ceph_put_cap(session->s_mdsc, old_cap);
913 old_cap = NULL;
916 ret = cb(inode, cap, arg);
917 last_inode = inode;
919 spin_lock(&session->s_cap_lock);
920 p = p->next;
921 if (cap->ci == NULL) {
922 dout("iterate_session_caps finishing cap %p removal\n",
923 cap);
924 BUG_ON(cap->session != session);
925 list_del_init(&cap->session_caps);
926 session->s_nr_caps--;
927 cap->session = NULL;
928 old_cap = cap; /* put_cap it w/o locks held */
930 if (ret < 0)
931 goto out;
933 ret = 0;
934 out:
935 session->s_cap_iterator = NULL;
936 spin_unlock(&session->s_cap_lock);
938 if (last_inode)
939 iput(last_inode);
940 if (old_cap)
941 ceph_put_cap(session->s_mdsc, old_cap);
943 return ret;
946 static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
947 void *arg)
949 struct ceph_inode_info *ci = ceph_inode(inode);
950 int drop = 0;
952 dout("removing cap %p, ci is %p, inode is %p\n",
953 cap, ci, &ci->vfs_inode);
954 spin_lock(&inode->i_lock);
955 __ceph_remove_cap(cap);
956 if (!__ceph_is_any_real_caps(ci)) {
957 struct ceph_mds_client *mdsc =
958 ceph_sb_to_client(inode->i_sb)->mdsc;
960 spin_lock(&mdsc->cap_dirty_lock);
961 if (!list_empty(&ci->i_dirty_item)) {
962 pr_info(" dropping dirty %s state for %p %lld\n",
963 ceph_cap_string(ci->i_dirty_caps),
964 inode, ceph_ino(inode));
965 ci->i_dirty_caps = 0;
966 list_del_init(&ci->i_dirty_item);
967 drop = 1;
969 if (!list_empty(&ci->i_flushing_item)) {
970 pr_info(" dropping dirty+flushing %s state for %p %lld\n",
971 ceph_cap_string(ci->i_flushing_caps),
972 inode, ceph_ino(inode));
973 ci->i_flushing_caps = 0;
974 list_del_init(&ci->i_flushing_item);
975 mdsc->num_cap_flushing--;
976 drop = 1;
978 if (drop && ci->i_wrbuffer_ref) {
979 pr_info(" dropping dirty data for %p %lld\n",
980 inode, ceph_ino(inode));
981 ci->i_wrbuffer_ref = 0;
982 ci->i_wrbuffer_ref_head = 0;
983 drop++;
985 spin_unlock(&mdsc->cap_dirty_lock);
987 spin_unlock(&inode->i_lock);
988 while (drop--)
989 iput(inode);
990 return 0;
994 * caller must hold session s_mutex
996 static void remove_session_caps(struct ceph_mds_session *session)
998 dout("remove_session_caps on %p\n", session);
999 iterate_session_caps(session, remove_session_caps_cb, NULL);
1000 BUG_ON(session->s_nr_caps > 0);
1001 BUG_ON(!list_empty(&session->s_cap_flushing));
1002 cleanup_cap_releases(session);
1006 * wake up any threads waiting on this session's caps. if the cap is
1007 * old (didn't get renewed on the client reconnect), remove it now.
1009 * caller must hold s_mutex.
1011 static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
1012 void *arg)
1014 struct ceph_inode_info *ci = ceph_inode(inode);
1016 wake_up_all(&ci->i_cap_wq);
1017 if (arg) {
1018 spin_lock(&inode->i_lock);
1019 ci->i_wanted_max_size = 0;
1020 ci->i_requested_max_size = 0;
1021 spin_unlock(&inode->i_lock);
1023 return 0;
1026 static void wake_up_session_caps(struct ceph_mds_session *session,
1027 int reconnect)
1029 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
1030 iterate_session_caps(session, wake_up_session_cb,
1031 (void *)(unsigned long)reconnect);
1035 * Send periodic message to MDS renewing all currently held caps. The
1036 * ack will reset the expiration for all caps from this session.
1038 * caller holds s_mutex
1040 static int send_renew_caps(struct ceph_mds_client *mdsc,
1041 struct ceph_mds_session *session)
1043 struct ceph_msg *msg;
1044 int state;
1046 if (time_after_eq(jiffies, session->s_cap_ttl) &&
1047 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
1048 pr_info("mds%d caps stale\n", session->s_mds);
1049 session->s_renew_requested = jiffies;
1051 /* do not try to renew caps until a recovering mds has reconnected
1052 * with its clients. */
1053 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
1054 if (state < CEPH_MDS_STATE_RECONNECT) {
1055 dout("send_renew_caps ignoring mds%d (%s)\n",
1056 session->s_mds, ceph_mds_state_name(state));
1057 return 0;
1060 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
1061 ceph_mds_state_name(state));
1062 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
1063 ++session->s_renew_seq);
1064 if (!msg)
1065 return -ENOMEM;
1066 ceph_con_send(&session->s_con, msg);
1067 return 0;
1071 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
1073 * Called under session->s_mutex
1075 static void renewed_caps(struct ceph_mds_client *mdsc,
1076 struct ceph_mds_session *session, int is_renew)
1078 int was_stale;
1079 int wake = 0;
1081 spin_lock(&session->s_cap_lock);
1082 was_stale = is_renew && (session->s_cap_ttl == 0 ||
1083 time_after_eq(jiffies, session->s_cap_ttl));
1085 session->s_cap_ttl = session->s_renew_requested +
1086 mdsc->mdsmap->m_session_timeout*HZ;
1088 if (was_stale) {
1089 if (time_before(jiffies, session->s_cap_ttl)) {
1090 pr_info("mds%d caps renewed\n", session->s_mds);
1091 wake = 1;
1092 } else {
1093 pr_info("mds%d caps still stale\n", session->s_mds);
1096 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
1097 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
1098 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
1099 spin_unlock(&session->s_cap_lock);
1101 if (wake)
1102 wake_up_session_caps(session, 0);
1106 * send a session close request
1108 static int request_close_session(struct ceph_mds_client *mdsc,
1109 struct ceph_mds_session *session)
1111 struct ceph_msg *msg;
1113 dout("request_close_session mds%d state %s seq %lld\n",
1114 session->s_mds, session_state_name(session->s_state),
1115 session->s_seq);
1116 msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
1117 if (!msg)
1118 return -ENOMEM;
1119 ceph_con_send(&session->s_con, msg);
1120 return 0;
1124 * Called with s_mutex held.
1126 static int __close_session(struct ceph_mds_client *mdsc,
1127 struct ceph_mds_session *session)
1129 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
1130 return 0;
1131 session->s_state = CEPH_MDS_SESSION_CLOSING;
1132 return request_close_session(mdsc, session);
1136 * Trim old(er) caps.
1138 * Because we can't cache an inode without one or more caps, we do
1139 * this indirectly: if a cap is unused, we prune its aliases, at which
1140 * point the inode will hopefully get dropped to.
1142 * Yes, this is a bit sloppy. Our only real goal here is to respond to
1143 * memory pressure from the MDS, though, so it needn't be perfect.
1145 static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
1147 struct ceph_mds_session *session = arg;
1148 struct ceph_inode_info *ci = ceph_inode(inode);
1149 int used, oissued, mine;
1151 if (session->s_trim_caps <= 0)
1152 return -1;
1154 spin_lock(&inode->i_lock);
1155 mine = cap->issued | cap->implemented;
1156 used = __ceph_caps_used(ci);
1157 oissued = __ceph_caps_issued_other(ci, cap);
1159 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s\n",
1160 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
1161 ceph_cap_string(used));
1162 if (ci->i_dirty_caps)
1163 goto out; /* dirty caps */
1164 if ((used & ~oissued) & mine)
1165 goto out; /* we need these caps */
1167 session->s_trim_caps--;
1168 if (oissued) {
1169 /* we aren't the only cap.. just remove us */
1170 __ceph_remove_cap(cap);
1171 } else {
1172 /* try to drop referring dentries */
1173 spin_unlock(&inode->i_lock);
1174 d_prune_aliases(inode);
1175 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
1176 inode, cap, atomic_read(&inode->i_count));
1177 return 0;
1180 out:
1181 spin_unlock(&inode->i_lock);
1182 return 0;
1186 * Trim session cap count down to some max number.
1188 static int trim_caps(struct ceph_mds_client *mdsc,
1189 struct ceph_mds_session *session,
1190 int max_caps)
1192 int trim_caps = session->s_nr_caps - max_caps;
1194 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1195 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1196 if (trim_caps > 0) {
1197 session->s_trim_caps = trim_caps;
1198 iterate_session_caps(session, trim_caps_cb, session);
1199 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1200 session->s_mds, session->s_nr_caps, max_caps,
1201 trim_caps - session->s_trim_caps);
1202 session->s_trim_caps = 0;
1204 return 0;
1208 * Allocate cap_release messages. If there is a partially full message
1209 * in the queue, try to allocate enough to cover it's remainder, so that
1210 * we can send it immediately.
1212 * Called under s_mutex.
1214 int ceph_add_cap_releases(struct ceph_mds_client *mdsc,
1215 struct ceph_mds_session *session)
1217 struct ceph_msg *msg, *partial = NULL;
1218 struct ceph_mds_cap_release *head;
1219 int err = -ENOMEM;
1220 int extra = mdsc->fsc->mount_options->cap_release_safety;
1221 int num;
1223 dout("add_cap_releases %p mds%d extra %d\n", session, session->s_mds,
1224 extra);
1226 spin_lock(&session->s_cap_lock);
1228 if (!list_empty(&session->s_cap_releases)) {
1229 msg = list_first_entry(&session->s_cap_releases,
1230 struct ceph_msg,
1231 list_head);
1232 head = msg->front.iov_base;
1233 num = le32_to_cpu(head->num);
1234 if (num) {
1235 dout(" partial %p with (%d/%d)\n", msg, num,
1236 (int)CEPH_CAPS_PER_RELEASE);
1237 extra += CEPH_CAPS_PER_RELEASE - num;
1238 partial = msg;
1241 while (session->s_num_cap_releases < session->s_nr_caps + extra) {
1242 spin_unlock(&session->s_cap_lock);
1243 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
1244 GFP_NOFS, false);
1245 if (!msg)
1246 goto out_unlocked;
1247 dout("add_cap_releases %p msg %p now %d\n", session, msg,
1248 (int)msg->front.iov_len);
1249 head = msg->front.iov_base;
1250 head->num = cpu_to_le32(0);
1251 msg->front.iov_len = sizeof(*head);
1252 spin_lock(&session->s_cap_lock);
1253 list_add(&msg->list_head, &session->s_cap_releases);
1254 session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
1257 if (partial) {
1258 head = partial->front.iov_base;
1259 num = le32_to_cpu(head->num);
1260 dout(" queueing partial %p with %d/%d\n", partial, num,
1261 (int)CEPH_CAPS_PER_RELEASE);
1262 list_move_tail(&partial->list_head,
1263 &session->s_cap_releases_done);
1264 session->s_num_cap_releases -= CEPH_CAPS_PER_RELEASE - num;
1266 err = 0;
1267 spin_unlock(&session->s_cap_lock);
1268 out_unlocked:
1269 return err;
1273 * flush all dirty inode data to disk.
1275 * returns true if we've flushed through want_flush_seq
1277 static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
1279 int mds, ret = 1;
1281 dout("check_cap_flush want %lld\n", want_flush_seq);
1282 mutex_lock(&mdsc->mutex);
1283 for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
1284 struct ceph_mds_session *session = mdsc->sessions[mds];
1286 if (!session)
1287 continue;
1288 get_session(session);
1289 mutex_unlock(&mdsc->mutex);
1291 mutex_lock(&session->s_mutex);
1292 if (!list_empty(&session->s_cap_flushing)) {
1293 struct ceph_inode_info *ci =
1294 list_entry(session->s_cap_flushing.next,
1295 struct ceph_inode_info,
1296 i_flushing_item);
1297 struct inode *inode = &ci->vfs_inode;
1299 spin_lock(&inode->i_lock);
1300 if (ci->i_cap_flush_seq <= want_flush_seq) {
1301 dout("check_cap_flush still flushing %p "
1302 "seq %lld <= %lld to mds%d\n", inode,
1303 ci->i_cap_flush_seq, want_flush_seq,
1304 session->s_mds);
1305 ret = 0;
1307 spin_unlock(&inode->i_lock);
1309 mutex_unlock(&session->s_mutex);
1310 ceph_put_mds_session(session);
1312 if (!ret)
1313 return ret;
1314 mutex_lock(&mdsc->mutex);
1317 mutex_unlock(&mdsc->mutex);
1318 dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
1319 return ret;
1323 * called under s_mutex
1325 void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
1326 struct ceph_mds_session *session)
1328 struct ceph_msg *msg;
1330 dout("send_cap_releases mds%d\n", session->s_mds);
1331 spin_lock(&session->s_cap_lock);
1332 while (!list_empty(&session->s_cap_releases_done)) {
1333 msg = list_first_entry(&session->s_cap_releases_done,
1334 struct ceph_msg, list_head);
1335 list_del_init(&msg->list_head);
1336 spin_unlock(&session->s_cap_lock);
1337 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1338 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1339 ceph_con_send(&session->s_con, msg);
1340 spin_lock(&session->s_cap_lock);
1342 spin_unlock(&session->s_cap_lock);
1345 static void discard_cap_releases(struct ceph_mds_client *mdsc,
1346 struct ceph_mds_session *session)
1348 struct ceph_msg *msg;
1349 struct ceph_mds_cap_release *head;
1350 unsigned num;
1352 dout("discard_cap_releases mds%d\n", session->s_mds);
1353 spin_lock(&session->s_cap_lock);
1355 /* zero out the in-progress message */
1356 msg = list_first_entry(&session->s_cap_releases,
1357 struct ceph_msg, list_head);
1358 head = msg->front.iov_base;
1359 num = le32_to_cpu(head->num);
1360 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, num);
1361 head->num = cpu_to_le32(0);
1362 session->s_num_cap_releases += num;
1364 /* requeue completed messages */
1365 while (!list_empty(&session->s_cap_releases_done)) {
1366 msg = list_first_entry(&session->s_cap_releases_done,
1367 struct ceph_msg, list_head);
1368 list_del_init(&msg->list_head);
1370 head = msg->front.iov_base;
1371 num = le32_to_cpu(head->num);
1372 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg,
1373 num);
1374 session->s_num_cap_releases += num;
1375 head->num = cpu_to_le32(0);
1376 msg->front.iov_len = sizeof(*head);
1377 list_add(&msg->list_head, &session->s_cap_releases);
1380 spin_unlock(&session->s_cap_lock);
1384 * requests
1388 * Create an mds request.
1390 struct ceph_mds_request *
1391 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1393 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1395 if (!req)
1396 return ERR_PTR(-ENOMEM);
1398 mutex_init(&req->r_fill_mutex);
1399 req->r_mdsc = mdsc;
1400 req->r_started = jiffies;
1401 req->r_resend_mds = -1;
1402 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1403 req->r_fmode = -1;
1404 kref_init(&req->r_kref);
1405 INIT_LIST_HEAD(&req->r_wait);
1406 init_completion(&req->r_completion);
1407 init_completion(&req->r_safe_completion);
1408 INIT_LIST_HEAD(&req->r_unsafe_item);
1410 req->r_op = op;
1411 req->r_direct_mode = mode;
1412 return req;
1416 * return oldest (lowest) request, tid in request tree, 0 if none.
1418 * called under mdsc->mutex.
1420 static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1422 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1423 return NULL;
1424 return rb_entry(rb_first(&mdsc->request_tree),
1425 struct ceph_mds_request, r_node);
1428 static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1430 struct ceph_mds_request *req = __get_oldest_req(mdsc);
1432 if (req)
1433 return req->r_tid;
1434 return 0;
1438 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1439 * on build_path_from_dentry in fs/cifs/dir.c.
1441 * If @stop_on_nosnap, generate path relative to the first non-snapped
1442 * inode.
1444 * Encode hidden .snap dirs as a double /, i.e.
1445 * foo/.snap/bar -> foo//bar
1447 char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1448 int stop_on_nosnap)
1450 struct dentry *temp;
1451 char *path;
1452 int len, pos;
1453 unsigned seq;
1455 if (dentry == NULL)
1456 return ERR_PTR(-EINVAL);
1458 retry:
1459 len = 0;
1460 seq = read_seqbegin(&rename_lock);
1461 rcu_read_lock();
1462 for (temp = dentry; !IS_ROOT(temp);) {
1463 struct inode *inode = temp->d_inode;
1464 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1465 len++; /* slash only */
1466 else if (stop_on_nosnap && inode &&
1467 ceph_snap(inode) == CEPH_NOSNAP)
1468 break;
1469 else
1470 len += 1 + temp->d_name.len;
1471 temp = temp->d_parent;
1472 if (temp == NULL) {
1473 rcu_read_unlock();
1474 pr_err("build_path corrupt dentry %p\n", dentry);
1475 return ERR_PTR(-EINVAL);
1478 rcu_read_unlock();
1479 if (len)
1480 len--; /* no leading '/' */
1482 path = kmalloc(len+1, GFP_NOFS);
1483 if (path == NULL)
1484 return ERR_PTR(-ENOMEM);
1485 pos = len;
1486 path[pos] = 0; /* trailing null */
1487 rcu_read_lock();
1488 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1489 struct inode *inode;
1491 spin_lock(&temp->d_lock);
1492 inode = temp->d_inode;
1493 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1494 dout("build_path path+%d: %p SNAPDIR\n",
1495 pos, temp);
1496 } else if (stop_on_nosnap && inode &&
1497 ceph_snap(inode) == CEPH_NOSNAP) {
1498 break;
1499 } else {
1500 pos -= temp->d_name.len;
1501 if (pos < 0) {
1502 spin_unlock(&temp->d_lock);
1503 break;
1505 strncpy(path + pos, temp->d_name.name,
1506 temp->d_name.len);
1508 spin_unlock(&temp->d_lock);
1509 if (pos)
1510 path[--pos] = '/';
1511 temp = temp->d_parent;
1512 if (temp == NULL) {
1513 rcu_read_unlock();
1514 pr_err("build_path corrupt dentry\n");
1515 kfree(path);
1516 return ERR_PTR(-EINVAL);
1519 rcu_read_unlock();
1520 if (pos != 0 || read_seqretry(&rename_lock, seq)) {
1521 pr_err("build_path did not end path lookup where "
1522 "expected, namelen is %d, pos is %d\n", len, pos);
1523 /* presumably this is only possible if racing with a
1524 rename of one of the parent directories (we can not
1525 lock the dentries above us to prevent this, but
1526 retrying should be harmless) */
1527 kfree(path);
1528 goto retry;
1531 *base = ceph_ino(temp->d_inode);
1532 *plen = len;
1533 dout("build_path on %p %d built %llx '%.*s'\n",
1534 dentry, dentry->d_count, *base, len, path);
1535 return path;
1538 static int build_dentry_path(struct dentry *dentry,
1539 const char **ppath, int *ppathlen, u64 *pino,
1540 int *pfreepath)
1542 char *path;
1544 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1545 *pino = ceph_ino(dentry->d_parent->d_inode);
1546 *ppath = dentry->d_name.name;
1547 *ppathlen = dentry->d_name.len;
1548 return 0;
1550 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1551 if (IS_ERR(path))
1552 return PTR_ERR(path);
1553 *ppath = path;
1554 *pfreepath = 1;
1555 return 0;
1558 static int build_inode_path(struct inode *inode,
1559 const char **ppath, int *ppathlen, u64 *pino,
1560 int *pfreepath)
1562 struct dentry *dentry;
1563 char *path;
1565 if (ceph_snap(inode) == CEPH_NOSNAP) {
1566 *pino = ceph_ino(inode);
1567 *ppathlen = 0;
1568 return 0;
1570 dentry = d_find_alias(inode);
1571 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1572 dput(dentry);
1573 if (IS_ERR(path))
1574 return PTR_ERR(path);
1575 *ppath = path;
1576 *pfreepath = 1;
1577 return 0;
1581 * request arguments may be specified via an inode *, a dentry *, or
1582 * an explicit ino+path.
1584 static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1585 const char *rpath, u64 rino,
1586 const char **ppath, int *pathlen,
1587 u64 *ino, int *freepath)
1589 int r = 0;
1591 if (rinode) {
1592 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1593 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1594 ceph_snap(rinode));
1595 } else if (rdentry) {
1596 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1597 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1598 *ppath);
1599 } else if (rpath) {
1600 *ino = rino;
1601 *ppath = rpath;
1602 *pathlen = strlen(rpath);
1603 dout(" path %.*s\n", *pathlen, rpath);
1606 return r;
1610 * called under mdsc->mutex
1612 static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1613 struct ceph_mds_request *req,
1614 int mds)
1616 struct ceph_msg *msg;
1617 struct ceph_mds_request_head *head;
1618 const char *path1 = NULL;
1619 const char *path2 = NULL;
1620 u64 ino1 = 0, ino2 = 0;
1621 int pathlen1 = 0, pathlen2 = 0;
1622 int freepath1 = 0, freepath2 = 0;
1623 int len;
1624 u16 releases;
1625 void *p, *end;
1626 int ret;
1628 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1629 req->r_path1, req->r_ino1.ino,
1630 &path1, &pathlen1, &ino1, &freepath1);
1631 if (ret < 0) {
1632 msg = ERR_PTR(ret);
1633 goto out;
1636 ret = set_request_path_attr(NULL, req->r_old_dentry,
1637 req->r_path2, req->r_ino2.ino,
1638 &path2, &pathlen2, &ino2, &freepath2);
1639 if (ret < 0) {
1640 msg = ERR_PTR(ret);
1641 goto out_free1;
1644 len = sizeof(*head) +
1645 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
1647 /* calculate (max) length for cap releases */
1648 len += sizeof(struct ceph_mds_request_release) *
1649 (!!req->r_inode_drop + !!req->r_dentry_drop +
1650 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1651 if (req->r_dentry_drop)
1652 len += req->r_dentry->d_name.len;
1653 if (req->r_old_dentry_drop)
1654 len += req->r_old_dentry->d_name.len;
1656 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS, false);
1657 if (!msg) {
1658 msg = ERR_PTR(-ENOMEM);
1659 goto out_free2;
1662 msg->hdr.tid = cpu_to_le64(req->r_tid);
1664 head = msg->front.iov_base;
1665 p = msg->front.iov_base + sizeof(*head);
1666 end = msg->front.iov_base + msg->front.iov_len;
1668 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1669 head->op = cpu_to_le32(req->r_op);
1670 head->caller_uid = cpu_to_le32(req->r_uid);
1671 head->caller_gid = cpu_to_le32(req->r_gid);
1672 head->args = req->r_args;
1674 ceph_encode_filepath(&p, end, ino1, path1);
1675 ceph_encode_filepath(&p, end, ino2, path2);
1677 /* make note of release offset, in case we need to replay */
1678 req->r_request_release_offset = p - msg->front.iov_base;
1680 /* cap releases */
1681 releases = 0;
1682 if (req->r_inode_drop)
1683 releases += ceph_encode_inode_release(&p,
1684 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1685 mds, req->r_inode_drop, req->r_inode_unless, 0);
1686 if (req->r_dentry_drop)
1687 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1688 mds, req->r_dentry_drop, req->r_dentry_unless);
1689 if (req->r_old_dentry_drop)
1690 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1691 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1692 if (req->r_old_inode_drop)
1693 releases += ceph_encode_inode_release(&p,
1694 req->r_old_dentry->d_inode,
1695 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1696 head->num_releases = cpu_to_le16(releases);
1698 BUG_ON(p > end);
1699 msg->front.iov_len = p - msg->front.iov_base;
1700 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1702 msg->pages = req->r_pages;
1703 msg->nr_pages = req->r_num_pages;
1704 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1705 msg->hdr.data_off = cpu_to_le16(0);
1707 out_free2:
1708 if (freepath2)
1709 kfree((char *)path2);
1710 out_free1:
1711 if (freepath1)
1712 kfree((char *)path1);
1713 out:
1714 return msg;
1718 * called under mdsc->mutex if error, under no mutex if
1719 * success.
1721 static void complete_request(struct ceph_mds_client *mdsc,
1722 struct ceph_mds_request *req)
1724 if (req->r_callback)
1725 req->r_callback(mdsc, req);
1726 else
1727 complete_all(&req->r_completion);
1731 * called under mdsc->mutex
1733 static int __prepare_send_request(struct ceph_mds_client *mdsc,
1734 struct ceph_mds_request *req,
1735 int mds)
1737 struct ceph_mds_request_head *rhead;
1738 struct ceph_msg *msg;
1739 int flags = 0;
1741 req->r_attempts++;
1742 if (req->r_inode) {
1743 struct ceph_cap *cap =
1744 ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
1746 if (cap)
1747 req->r_sent_on_mseq = cap->mseq;
1748 else
1749 req->r_sent_on_mseq = -1;
1751 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1752 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1754 if (req->r_got_unsafe) {
1756 * Replay. Do not regenerate message (and rebuild
1757 * paths, etc.); just use the original message.
1758 * Rebuilding paths will break for renames because
1759 * d_move mangles the src name.
1761 msg = req->r_request;
1762 rhead = msg->front.iov_base;
1764 flags = le32_to_cpu(rhead->flags);
1765 flags |= CEPH_MDS_FLAG_REPLAY;
1766 rhead->flags = cpu_to_le32(flags);
1768 if (req->r_target_inode)
1769 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1771 rhead->num_retry = req->r_attempts - 1;
1773 /* remove cap/dentry releases from message */
1774 rhead->num_releases = 0;
1775 msg->hdr.front_len = cpu_to_le32(req->r_request_release_offset);
1776 msg->front.iov_len = req->r_request_release_offset;
1777 return 0;
1780 if (req->r_request) {
1781 ceph_msg_put(req->r_request);
1782 req->r_request = NULL;
1784 msg = create_request_message(mdsc, req, mds);
1785 if (IS_ERR(msg)) {
1786 req->r_err = PTR_ERR(msg);
1787 complete_request(mdsc, req);
1788 return PTR_ERR(msg);
1790 req->r_request = msg;
1792 rhead = msg->front.iov_base;
1793 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1794 if (req->r_got_unsafe)
1795 flags |= CEPH_MDS_FLAG_REPLAY;
1796 if (req->r_locked_dir)
1797 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1798 rhead->flags = cpu_to_le32(flags);
1799 rhead->num_fwd = req->r_num_fwd;
1800 rhead->num_retry = req->r_attempts - 1;
1801 rhead->ino = 0;
1803 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1804 return 0;
1808 * send request, or put it on the appropriate wait list.
1810 static int __do_request(struct ceph_mds_client *mdsc,
1811 struct ceph_mds_request *req)
1813 struct ceph_mds_session *session = NULL;
1814 int mds = -1;
1815 int err = -EAGAIN;
1817 if (req->r_err || req->r_got_result)
1818 goto out;
1820 if (req->r_timeout &&
1821 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1822 dout("do_request timed out\n");
1823 err = -EIO;
1824 goto finish;
1827 put_request_session(req);
1829 mds = __choose_mds(mdsc, req);
1830 if (mds < 0 ||
1831 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1832 dout("do_request no mds or not active, waiting for map\n");
1833 list_add(&req->r_wait, &mdsc->waiting_for_map);
1834 goto out;
1837 /* get, open session */
1838 session = __ceph_lookup_mds_session(mdsc, mds);
1839 if (!session) {
1840 session = register_session(mdsc, mds);
1841 if (IS_ERR(session)) {
1842 err = PTR_ERR(session);
1843 goto finish;
1846 req->r_session = get_session(session);
1848 dout("do_request mds%d session %p state %s\n", mds, session,
1849 session_state_name(session->s_state));
1850 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
1851 session->s_state != CEPH_MDS_SESSION_HUNG) {
1852 if (session->s_state == CEPH_MDS_SESSION_NEW ||
1853 session->s_state == CEPH_MDS_SESSION_CLOSING)
1854 __open_session(mdsc, session);
1855 list_add(&req->r_wait, &session->s_waiting);
1856 goto out_session;
1859 /* send request */
1860 req->r_resend_mds = -1; /* forget any previous mds hint */
1862 if (req->r_request_started == 0) /* note request start time */
1863 req->r_request_started = jiffies;
1865 err = __prepare_send_request(mdsc, req, mds);
1866 if (!err) {
1867 ceph_msg_get(req->r_request);
1868 ceph_con_send(&session->s_con, req->r_request);
1871 out_session:
1872 ceph_put_mds_session(session);
1873 out:
1874 return err;
1876 finish:
1877 req->r_err = err;
1878 complete_request(mdsc, req);
1879 goto out;
1883 * called under mdsc->mutex
1885 static void __wake_requests(struct ceph_mds_client *mdsc,
1886 struct list_head *head)
1888 struct ceph_mds_request *req, *nreq;
1890 list_for_each_entry_safe(req, nreq, head, r_wait) {
1891 list_del_init(&req->r_wait);
1892 __do_request(mdsc, req);
1897 * Wake up threads with requests pending for @mds, so that they can
1898 * resubmit their requests to a possibly different mds.
1900 static void kick_requests(struct ceph_mds_client *mdsc, int mds)
1902 struct ceph_mds_request *req;
1903 struct rb_node *p;
1905 dout("kick_requests mds%d\n", mds);
1906 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
1907 req = rb_entry(p, struct ceph_mds_request, r_node);
1908 if (req->r_got_unsafe)
1909 continue;
1910 if (req->r_session &&
1911 req->r_session->s_mds == mds) {
1912 dout(" kicking tid %llu\n", req->r_tid);
1913 __do_request(mdsc, req);
1918 void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
1919 struct ceph_mds_request *req)
1921 dout("submit_request on %p\n", req);
1922 mutex_lock(&mdsc->mutex);
1923 __register_request(mdsc, req, NULL);
1924 __do_request(mdsc, req);
1925 mutex_unlock(&mdsc->mutex);
1929 * Synchrously perform an mds request. Take care of all of the
1930 * session setup, forwarding, retry details.
1932 int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
1933 struct inode *dir,
1934 struct ceph_mds_request *req)
1936 int err;
1938 dout("do_request on %p\n", req);
1940 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
1941 if (req->r_inode)
1942 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
1943 if (req->r_locked_dir)
1944 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
1945 if (req->r_old_dentry)
1946 ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
1947 CEPH_CAP_PIN);
1949 /* issue */
1950 mutex_lock(&mdsc->mutex);
1951 __register_request(mdsc, req, dir);
1952 __do_request(mdsc, req);
1954 if (req->r_err) {
1955 err = req->r_err;
1956 __unregister_request(mdsc, req);
1957 dout("do_request early error %d\n", err);
1958 goto out;
1961 /* wait */
1962 mutex_unlock(&mdsc->mutex);
1963 dout("do_request waiting\n");
1964 if (req->r_timeout) {
1965 err = (long)wait_for_completion_killable_timeout(
1966 &req->r_completion, req->r_timeout);
1967 if (err == 0)
1968 err = -EIO;
1969 } else {
1970 err = wait_for_completion_killable(&req->r_completion);
1972 dout("do_request waited, got %d\n", err);
1973 mutex_lock(&mdsc->mutex);
1975 /* only abort if we didn't race with a real reply */
1976 if (req->r_got_result) {
1977 err = le32_to_cpu(req->r_reply_info.head->result);
1978 } else if (err < 0) {
1979 dout("aborted request %lld with %d\n", req->r_tid, err);
1982 * ensure we aren't running concurrently with
1983 * ceph_fill_trace or ceph_readdir_prepopulate, which
1984 * rely on locks (dir mutex) held by our caller.
1986 mutex_lock(&req->r_fill_mutex);
1987 req->r_err = err;
1988 req->r_aborted = true;
1989 mutex_unlock(&req->r_fill_mutex);
1991 if (req->r_locked_dir &&
1992 (req->r_op & CEPH_MDS_OP_WRITE))
1993 ceph_invalidate_dir_request(req);
1994 } else {
1995 err = req->r_err;
1998 out:
1999 mutex_unlock(&mdsc->mutex);
2000 dout("do_request %p done, result %d\n", req, err);
2001 return err;
2005 * Invalidate dir I_COMPLETE, dentry lease state on an aborted MDS
2006 * namespace request.
2008 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
2010 struct inode *inode = req->r_locked_dir;
2011 struct ceph_inode_info *ci = ceph_inode(inode);
2013 dout("invalidate_dir_request %p (I_COMPLETE, lease(s))\n", inode);
2014 spin_lock(&inode->i_lock);
2015 ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
2016 ci->i_release_count++;
2017 spin_unlock(&inode->i_lock);
2019 if (req->r_dentry)
2020 ceph_invalidate_dentry_lease(req->r_dentry);
2021 if (req->r_old_dentry)
2022 ceph_invalidate_dentry_lease(req->r_old_dentry);
2026 * Handle mds reply.
2028 * We take the session mutex and parse and process the reply immediately.
2029 * This preserves the logical ordering of replies, capabilities, etc., sent
2030 * by the MDS as they are applied to our local cache.
2032 static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
2034 struct ceph_mds_client *mdsc = session->s_mdsc;
2035 struct ceph_mds_request *req;
2036 struct ceph_mds_reply_head *head = msg->front.iov_base;
2037 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
2038 u64 tid;
2039 int err, result;
2040 int mds = session->s_mds;
2042 if (msg->front.iov_len < sizeof(*head)) {
2043 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
2044 ceph_msg_dump(msg);
2045 return;
2048 /* get request, session */
2049 tid = le64_to_cpu(msg->hdr.tid);
2050 mutex_lock(&mdsc->mutex);
2051 req = __lookup_request(mdsc, tid);
2052 if (!req) {
2053 dout("handle_reply on unknown tid %llu\n", tid);
2054 mutex_unlock(&mdsc->mutex);
2055 return;
2057 dout("handle_reply %p\n", req);
2059 /* correct session? */
2060 if (req->r_session != session) {
2061 pr_err("mdsc_handle_reply got %llu on session mds%d"
2062 " not mds%d\n", tid, session->s_mds,
2063 req->r_session ? req->r_session->s_mds : -1);
2064 mutex_unlock(&mdsc->mutex);
2065 goto out;
2068 /* dup? */
2069 if ((req->r_got_unsafe && !head->safe) ||
2070 (req->r_got_safe && head->safe)) {
2071 pr_warning("got a dup %s reply on %llu from mds%d\n",
2072 head->safe ? "safe" : "unsafe", tid, mds);
2073 mutex_unlock(&mdsc->mutex);
2074 goto out;
2076 if (req->r_got_safe && !head->safe) {
2077 pr_warning("got unsafe after safe on %llu from mds%d\n",
2078 tid, mds);
2079 mutex_unlock(&mdsc->mutex);
2080 goto out;
2083 result = le32_to_cpu(head->result);
2086 * Handle an ESTALE
2087 * if we're not talking to the authority, send to them
2088 * if the authority has changed while we weren't looking,
2089 * send to new authority
2090 * Otherwise we just have to return an ESTALE
2092 if (result == -ESTALE) {
2093 dout("got ESTALE on request %llu", req->r_tid);
2094 if (!req->r_inode) {
2095 /* do nothing; not an authority problem */
2096 } else if (req->r_direct_mode != USE_AUTH_MDS) {
2097 dout("not using auth, setting for that now");
2098 req->r_direct_mode = USE_AUTH_MDS;
2099 __do_request(mdsc, req);
2100 mutex_unlock(&mdsc->mutex);
2101 goto out;
2102 } else {
2103 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
2104 struct ceph_cap *cap = NULL;
2106 if (req->r_session)
2107 cap = ceph_get_cap_for_mds(ci,
2108 req->r_session->s_mds);
2110 dout("already using auth");
2111 if ((!cap || cap != ci->i_auth_cap) ||
2112 (cap->mseq != req->r_sent_on_mseq)) {
2113 dout("but cap changed, so resending");
2114 __do_request(mdsc, req);
2115 mutex_unlock(&mdsc->mutex);
2116 goto out;
2119 dout("have to return ESTALE on request %llu", req->r_tid);
2123 if (head->safe) {
2124 req->r_got_safe = true;
2125 __unregister_request(mdsc, req);
2126 complete_all(&req->r_safe_completion);
2128 if (req->r_got_unsafe) {
2130 * We already handled the unsafe response, now do the
2131 * cleanup. No need to examine the response; the MDS
2132 * doesn't include any result info in the safe
2133 * response. And even if it did, there is nothing
2134 * useful we could do with a revised return value.
2136 dout("got safe reply %llu, mds%d\n", tid, mds);
2137 list_del_init(&req->r_unsafe_item);
2139 /* last unsafe request during umount? */
2140 if (mdsc->stopping && !__get_oldest_req(mdsc))
2141 complete_all(&mdsc->safe_umount_waiters);
2142 mutex_unlock(&mdsc->mutex);
2143 goto out;
2145 } else {
2146 req->r_got_unsafe = true;
2147 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
2150 dout("handle_reply tid %lld result %d\n", tid, result);
2151 rinfo = &req->r_reply_info;
2152 err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
2153 mutex_unlock(&mdsc->mutex);
2155 mutex_lock(&session->s_mutex);
2156 if (err < 0) {
2157 pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
2158 ceph_msg_dump(msg);
2159 goto out_err;
2162 /* snap trace */
2163 if (rinfo->snapblob_len) {
2164 down_write(&mdsc->snap_rwsem);
2165 ceph_update_snap_trace(mdsc, rinfo->snapblob,
2166 rinfo->snapblob + rinfo->snapblob_len,
2167 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
2168 downgrade_write(&mdsc->snap_rwsem);
2169 } else {
2170 down_read(&mdsc->snap_rwsem);
2173 /* insert trace into our cache */
2174 mutex_lock(&req->r_fill_mutex);
2175 err = ceph_fill_trace(mdsc->fsc->sb, req, req->r_session);
2176 if (err == 0) {
2177 if (result == 0 && req->r_op != CEPH_MDS_OP_GETFILELOCK &&
2178 rinfo->dir_nr)
2179 ceph_readdir_prepopulate(req, req->r_session);
2180 ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
2182 mutex_unlock(&req->r_fill_mutex);
2184 up_read(&mdsc->snap_rwsem);
2185 out_err:
2186 mutex_lock(&mdsc->mutex);
2187 if (!req->r_aborted) {
2188 if (err) {
2189 req->r_err = err;
2190 } else {
2191 req->r_reply = msg;
2192 ceph_msg_get(msg);
2193 req->r_got_result = true;
2195 } else {
2196 dout("reply arrived after request %lld was aborted\n", tid);
2198 mutex_unlock(&mdsc->mutex);
2200 ceph_add_cap_releases(mdsc, req->r_session);
2201 mutex_unlock(&session->s_mutex);
2203 /* kick calling process */
2204 complete_request(mdsc, req);
2205 out:
2206 ceph_mdsc_put_request(req);
2207 return;
2213 * handle mds notification that our request has been forwarded.
2215 static void handle_forward(struct ceph_mds_client *mdsc,
2216 struct ceph_mds_session *session,
2217 struct ceph_msg *msg)
2219 struct ceph_mds_request *req;
2220 u64 tid = le64_to_cpu(msg->hdr.tid);
2221 u32 next_mds;
2222 u32 fwd_seq;
2223 int err = -EINVAL;
2224 void *p = msg->front.iov_base;
2225 void *end = p + msg->front.iov_len;
2227 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
2228 next_mds = ceph_decode_32(&p);
2229 fwd_seq = ceph_decode_32(&p);
2231 mutex_lock(&mdsc->mutex);
2232 req = __lookup_request(mdsc, tid);
2233 if (!req) {
2234 dout("forward tid %llu to mds%d - req dne\n", tid, next_mds);
2235 goto out; /* dup reply? */
2238 if (req->r_aborted) {
2239 dout("forward tid %llu aborted, unregistering\n", tid);
2240 __unregister_request(mdsc, req);
2241 } else if (fwd_seq <= req->r_num_fwd) {
2242 dout("forward tid %llu to mds%d - old seq %d <= %d\n",
2243 tid, next_mds, req->r_num_fwd, fwd_seq);
2244 } else {
2245 /* resend. forward race not possible; mds would drop */
2246 dout("forward tid %llu to mds%d (we resend)\n", tid, next_mds);
2247 BUG_ON(req->r_err);
2248 BUG_ON(req->r_got_result);
2249 req->r_num_fwd = fwd_seq;
2250 req->r_resend_mds = next_mds;
2251 put_request_session(req);
2252 __do_request(mdsc, req);
2254 ceph_mdsc_put_request(req);
2255 out:
2256 mutex_unlock(&mdsc->mutex);
2257 return;
2259 bad:
2260 pr_err("mdsc_handle_forward decode error err=%d\n", err);
2264 * handle a mds session control message
2266 static void handle_session(struct ceph_mds_session *session,
2267 struct ceph_msg *msg)
2269 struct ceph_mds_client *mdsc = session->s_mdsc;
2270 u32 op;
2271 u64 seq;
2272 int mds = session->s_mds;
2273 struct ceph_mds_session_head *h = msg->front.iov_base;
2274 int wake = 0;
2276 /* decode */
2277 if (msg->front.iov_len != sizeof(*h))
2278 goto bad;
2279 op = le32_to_cpu(h->op);
2280 seq = le64_to_cpu(h->seq);
2282 mutex_lock(&mdsc->mutex);
2283 if (op == CEPH_SESSION_CLOSE)
2284 __unregister_session(mdsc, session);
2285 /* FIXME: this ttl calculation is generous */
2286 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2287 mutex_unlock(&mdsc->mutex);
2289 mutex_lock(&session->s_mutex);
2291 dout("handle_session mds%d %s %p state %s seq %llu\n",
2292 mds, ceph_session_op_name(op), session,
2293 session_state_name(session->s_state), seq);
2295 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2296 session->s_state = CEPH_MDS_SESSION_OPEN;
2297 pr_info("mds%d came back\n", session->s_mds);
2300 switch (op) {
2301 case CEPH_SESSION_OPEN:
2302 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2303 pr_info("mds%d reconnect success\n", session->s_mds);
2304 session->s_state = CEPH_MDS_SESSION_OPEN;
2305 renewed_caps(mdsc, session, 0);
2306 wake = 1;
2307 if (mdsc->stopping)
2308 __close_session(mdsc, session);
2309 break;
2311 case CEPH_SESSION_RENEWCAPS:
2312 if (session->s_renew_seq == seq)
2313 renewed_caps(mdsc, session, 1);
2314 break;
2316 case CEPH_SESSION_CLOSE:
2317 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2318 pr_info("mds%d reconnect denied\n", session->s_mds);
2319 remove_session_caps(session);
2320 wake = 1; /* for good measure */
2321 wake_up_all(&mdsc->session_close_wq);
2322 kick_requests(mdsc, mds);
2323 break;
2325 case CEPH_SESSION_STALE:
2326 pr_info("mds%d caps went stale, renewing\n",
2327 session->s_mds);
2328 spin_lock(&session->s_cap_lock);
2329 session->s_cap_gen++;
2330 session->s_cap_ttl = 0;
2331 spin_unlock(&session->s_cap_lock);
2332 send_renew_caps(mdsc, session);
2333 break;
2335 case CEPH_SESSION_RECALL_STATE:
2336 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2337 break;
2339 default:
2340 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2341 WARN_ON(1);
2344 mutex_unlock(&session->s_mutex);
2345 if (wake) {
2346 mutex_lock(&mdsc->mutex);
2347 __wake_requests(mdsc, &session->s_waiting);
2348 mutex_unlock(&mdsc->mutex);
2350 return;
2352 bad:
2353 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2354 (int)msg->front.iov_len);
2355 ceph_msg_dump(msg);
2356 return;
2361 * called under session->mutex.
2363 static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2364 struct ceph_mds_session *session)
2366 struct ceph_mds_request *req, *nreq;
2367 int err;
2369 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2371 mutex_lock(&mdsc->mutex);
2372 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2373 err = __prepare_send_request(mdsc, req, session->s_mds);
2374 if (!err) {
2375 ceph_msg_get(req->r_request);
2376 ceph_con_send(&session->s_con, req->r_request);
2379 mutex_unlock(&mdsc->mutex);
2383 * Encode information about a cap for a reconnect with the MDS.
2385 static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2386 void *arg)
2388 union {
2389 struct ceph_mds_cap_reconnect v2;
2390 struct ceph_mds_cap_reconnect_v1 v1;
2391 } rec;
2392 size_t reclen;
2393 struct ceph_inode_info *ci;
2394 struct ceph_reconnect_state *recon_state = arg;
2395 struct ceph_pagelist *pagelist = recon_state->pagelist;
2396 char *path;
2397 int pathlen, err;
2398 u64 pathbase;
2399 struct dentry *dentry;
2401 ci = cap->ci;
2403 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2404 inode, ceph_vinop(inode), cap, cap->cap_id,
2405 ceph_cap_string(cap->issued));
2406 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2407 if (err)
2408 return err;
2410 dentry = d_find_alias(inode);
2411 if (dentry) {
2412 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2413 if (IS_ERR(path)) {
2414 err = PTR_ERR(path);
2415 goto out_dput;
2417 } else {
2418 path = NULL;
2419 pathlen = 0;
2421 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2422 if (err)
2423 goto out_free;
2425 spin_lock(&inode->i_lock);
2426 cap->seq = 0; /* reset cap seq */
2427 cap->issue_seq = 0; /* and issue_seq */
2429 if (recon_state->flock) {
2430 rec.v2.cap_id = cpu_to_le64(cap->cap_id);
2431 rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2432 rec.v2.issued = cpu_to_le32(cap->issued);
2433 rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2434 rec.v2.pathbase = cpu_to_le64(pathbase);
2435 rec.v2.flock_len = 0;
2436 reclen = sizeof(rec.v2);
2437 } else {
2438 rec.v1.cap_id = cpu_to_le64(cap->cap_id);
2439 rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2440 rec.v1.issued = cpu_to_le32(cap->issued);
2441 rec.v1.size = cpu_to_le64(inode->i_size);
2442 ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
2443 ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
2444 rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2445 rec.v1.pathbase = cpu_to_le64(pathbase);
2446 reclen = sizeof(rec.v1);
2448 spin_unlock(&inode->i_lock);
2450 if (recon_state->flock) {
2451 int num_fcntl_locks, num_flock_locks;
2452 struct ceph_pagelist_cursor trunc_point;
2454 ceph_pagelist_set_cursor(pagelist, &trunc_point);
2455 do {
2456 lock_flocks();
2457 ceph_count_locks(inode, &num_fcntl_locks,
2458 &num_flock_locks);
2459 rec.v2.flock_len = (2*sizeof(u32) +
2460 (num_fcntl_locks+num_flock_locks) *
2461 sizeof(struct ceph_filelock));
2462 unlock_flocks();
2464 /* pre-alloc pagelist */
2465 ceph_pagelist_truncate(pagelist, &trunc_point);
2466 err = ceph_pagelist_append(pagelist, &rec, reclen);
2467 if (!err)
2468 err = ceph_pagelist_reserve(pagelist,
2469 rec.v2.flock_len);
2471 /* encode locks */
2472 if (!err) {
2473 lock_flocks();
2474 err = ceph_encode_locks(inode,
2475 pagelist,
2476 num_fcntl_locks,
2477 num_flock_locks);
2478 unlock_flocks();
2480 } while (err == -ENOSPC);
2481 } else {
2482 err = ceph_pagelist_append(pagelist, &rec, reclen);
2485 out_free:
2486 kfree(path);
2487 out_dput:
2488 dput(dentry);
2489 return err;
2494 * If an MDS fails and recovers, clients need to reconnect in order to
2495 * reestablish shared state. This includes all caps issued through
2496 * this session _and_ the snap_realm hierarchy. Because it's not
2497 * clear which snap realms the mds cares about, we send everything we
2498 * know about.. that ensures we'll then get any new info the
2499 * recovering MDS might have.
2501 * This is a relatively heavyweight operation, but it's rare.
2503 * called with mdsc->mutex held.
2505 static void send_mds_reconnect(struct ceph_mds_client *mdsc,
2506 struct ceph_mds_session *session)
2508 struct ceph_msg *reply;
2509 struct rb_node *p;
2510 int mds = session->s_mds;
2511 int err = -ENOMEM;
2512 struct ceph_pagelist *pagelist;
2513 struct ceph_reconnect_state recon_state;
2515 pr_info("mds%d reconnect start\n", mds);
2517 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2518 if (!pagelist)
2519 goto fail_nopagelist;
2520 ceph_pagelist_init(pagelist);
2522 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS, false);
2523 if (!reply)
2524 goto fail_nomsg;
2526 mutex_lock(&session->s_mutex);
2527 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2528 session->s_seq = 0;
2530 ceph_con_open(&session->s_con,
2531 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2533 /* replay unsafe requests */
2534 replay_unsafe_requests(mdsc, session);
2536 down_read(&mdsc->snap_rwsem);
2538 dout("session %p state %s\n", session,
2539 session_state_name(session->s_state));
2541 /* drop old cap expires; we're about to reestablish that state */
2542 discard_cap_releases(mdsc, session);
2544 /* traverse this session's caps */
2545 err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
2546 if (err)
2547 goto fail;
2549 recon_state.pagelist = pagelist;
2550 recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK;
2551 err = iterate_session_caps(session, encode_caps_cb, &recon_state);
2552 if (err < 0)
2553 goto fail;
2556 * snaprealms. we provide mds with the ino, seq (version), and
2557 * parent for all of our realms. If the mds has any newer info,
2558 * it will tell us.
2560 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2561 struct ceph_snap_realm *realm =
2562 rb_entry(p, struct ceph_snap_realm, node);
2563 struct ceph_mds_snaprealm_reconnect sr_rec;
2565 dout(" adding snap realm %llx seq %lld parent %llx\n",
2566 realm->ino, realm->seq, realm->parent_ino);
2567 sr_rec.ino = cpu_to_le64(realm->ino);
2568 sr_rec.seq = cpu_to_le64(realm->seq);
2569 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2570 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2571 if (err)
2572 goto fail;
2575 reply->pagelist = pagelist;
2576 if (recon_state.flock)
2577 reply->hdr.version = cpu_to_le16(2);
2578 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2579 reply->nr_pages = calc_pages_for(0, pagelist->length);
2580 ceph_con_send(&session->s_con, reply);
2582 mutex_unlock(&session->s_mutex);
2584 mutex_lock(&mdsc->mutex);
2585 __wake_requests(mdsc, &session->s_waiting);
2586 mutex_unlock(&mdsc->mutex);
2588 up_read(&mdsc->snap_rwsem);
2589 return;
2591 fail:
2592 ceph_msg_put(reply);
2593 up_read(&mdsc->snap_rwsem);
2594 mutex_unlock(&session->s_mutex);
2595 fail_nomsg:
2596 ceph_pagelist_release(pagelist);
2597 kfree(pagelist);
2598 fail_nopagelist:
2599 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
2600 return;
2605 * compare old and new mdsmaps, kicking requests
2606 * and closing out old connections as necessary
2608 * called under mdsc->mutex.
2610 static void check_new_map(struct ceph_mds_client *mdsc,
2611 struct ceph_mdsmap *newmap,
2612 struct ceph_mdsmap *oldmap)
2614 int i;
2615 int oldstate, newstate;
2616 struct ceph_mds_session *s;
2618 dout("check_new_map new %u old %u\n",
2619 newmap->m_epoch, oldmap->m_epoch);
2621 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2622 if (mdsc->sessions[i] == NULL)
2623 continue;
2624 s = mdsc->sessions[i];
2625 oldstate = ceph_mdsmap_get_state(oldmap, i);
2626 newstate = ceph_mdsmap_get_state(newmap, i);
2628 dout("check_new_map mds%d state %s%s -> %s%s (session %s)\n",
2629 i, ceph_mds_state_name(oldstate),
2630 ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "",
2631 ceph_mds_state_name(newstate),
2632 ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
2633 session_state_name(s->s_state));
2635 if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
2636 ceph_mdsmap_get_addr(newmap, i),
2637 sizeof(struct ceph_entity_addr))) {
2638 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2639 /* the session never opened, just close it
2640 * out now */
2641 __wake_requests(mdsc, &s->s_waiting);
2642 __unregister_session(mdsc, s);
2643 } else {
2644 /* just close it */
2645 mutex_unlock(&mdsc->mutex);
2646 mutex_lock(&s->s_mutex);
2647 mutex_lock(&mdsc->mutex);
2648 ceph_con_close(&s->s_con);
2649 mutex_unlock(&s->s_mutex);
2650 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2653 /* kick any requests waiting on the recovering mds */
2654 kick_requests(mdsc, i);
2655 } else if (oldstate == newstate) {
2656 continue; /* nothing new with this mds */
2660 * send reconnect?
2662 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2663 newstate >= CEPH_MDS_STATE_RECONNECT) {
2664 mutex_unlock(&mdsc->mutex);
2665 send_mds_reconnect(mdsc, s);
2666 mutex_lock(&mdsc->mutex);
2670 * kick request on any mds that has gone active.
2672 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2673 newstate >= CEPH_MDS_STATE_ACTIVE) {
2674 if (oldstate != CEPH_MDS_STATE_CREATING &&
2675 oldstate != CEPH_MDS_STATE_STARTING)
2676 pr_info("mds%d recovery completed\n", s->s_mds);
2677 kick_requests(mdsc, i);
2678 ceph_kick_flushing_caps(mdsc, s);
2679 wake_up_session_caps(s, 1);
2683 for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
2684 s = mdsc->sessions[i];
2685 if (!s)
2686 continue;
2687 if (!ceph_mdsmap_is_laggy(newmap, i))
2688 continue;
2689 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2690 s->s_state == CEPH_MDS_SESSION_HUNG ||
2691 s->s_state == CEPH_MDS_SESSION_CLOSING) {
2692 dout(" connecting to export targets of laggy mds%d\n",
2694 __open_export_target_sessions(mdsc, s);
2702 * leases
2706 * caller must hold session s_mutex, dentry->d_lock
2708 void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2710 struct ceph_dentry_info *di = ceph_dentry(dentry);
2712 ceph_put_mds_session(di->lease_session);
2713 di->lease_session = NULL;
2716 static void handle_lease(struct ceph_mds_client *mdsc,
2717 struct ceph_mds_session *session,
2718 struct ceph_msg *msg)
2720 struct super_block *sb = mdsc->fsc->sb;
2721 struct inode *inode;
2722 struct dentry *parent, *dentry;
2723 struct ceph_dentry_info *di;
2724 int mds = session->s_mds;
2725 struct ceph_mds_lease *h = msg->front.iov_base;
2726 u32 seq;
2727 struct ceph_vino vino;
2728 struct qstr dname;
2729 int release = 0;
2731 dout("handle_lease from mds%d\n", mds);
2733 /* decode */
2734 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2735 goto bad;
2736 vino.ino = le64_to_cpu(h->ino);
2737 vino.snap = CEPH_NOSNAP;
2738 seq = le32_to_cpu(h->seq);
2739 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2740 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2741 if (dname.len != get_unaligned_le32(h+1))
2742 goto bad;
2744 mutex_lock(&session->s_mutex);
2745 session->s_seq++;
2747 /* lookup inode */
2748 inode = ceph_find_inode(sb, vino);
2749 dout("handle_lease %s, ino %llx %p %.*s\n",
2750 ceph_lease_op_name(h->action), vino.ino, inode,
2751 dname.len, dname.name);
2752 if (inode == NULL) {
2753 dout("handle_lease no inode %llx\n", vino.ino);
2754 goto release;
2757 /* dentry */
2758 parent = d_find_alias(inode);
2759 if (!parent) {
2760 dout("no parent dentry on inode %p\n", inode);
2761 WARN_ON(1);
2762 goto release; /* hrm... */
2764 dname.hash = full_name_hash(dname.name, dname.len);
2765 dentry = d_lookup(parent, &dname);
2766 dput(parent);
2767 if (!dentry)
2768 goto release;
2770 spin_lock(&dentry->d_lock);
2771 di = ceph_dentry(dentry);
2772 switch (h->action) {
2773 case CEPH_MDS_LEASE_REVOKE:
2774 if (di && di->lease_session == session) {
2775 if (ceph_seq_cmp(di->lease_seq, seq) > 0)
2776 h->seq = cpu_to_le32(di->lease_seq);
2777 __ceph_mdsc_drop_dentry_lease(dentry);
2779 release = 1;
2780 break;
2782 case CEPH_MDS_LEASE_RENEW:
2783 if (di && di->lease_session == session &&
2784 di->lease_gen == session->s_cap_gen &&
2785 di->lease_renew_from &&
2786 di->lease_renew_after == 0) {
2787 unsigned long duration =
2788 le32_to_cpu(h->duration_ms) * HZ / 1000;
2790 di->lease_seq = seq;
2791 dentry->d_time = di->lease_renew_from + duration;
2792 di->lease_renew_after = di->lease_renew_from +
2793 (duration >> 1);
2794 di->lease_renew_from = 0;
2796 break;
2798 spin_unlock(&dentry->d_lock);
2799 dput(dentry);
2801 if (!release)
2802 goto out;
2804 release:
2805 /* let's just reuse the same message */
2806 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2807 ceph_msg_get(msg);
2808 ceph_con_send(&session->s_con, msg);
2810 out:
2811 iput(inode);
2812 mutex_unlock(&session->s_mutex);
2813 return;
2815 bad:
2816 pr_err("corrupt lease message\n");
2817 ceph_msg_dump(msg);
2820 void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
2821 struct inode *inode,
2822 struct dentry *dentry, char action,
2823 u32 seq)
2825 struct ceph_msg *msg;
2826 struct ceph_mds_lease *lease;
2827 int len = sizeof(*lease) + sizeof(u32);
2828 int dnamelen = 0;
2830 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
2831 inode, dentry, ceph_lease_op_name(action), session->s_mds);
2832 dnamelen = dentry->d_name.len;
2833 len += dnamelen;
2835 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false);
2836 if (!msg)
2837 return;
2838 lease = msg->front.iov_base;
2839 lease->action = action;
2840 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
2841 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
2842 lease->seq = cpu_to_le32(seq);
2843 put_unaligned_le32(dnamelen, lease + 1);
2844 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
2847 * if this is a preemptive lease RELEASE, no need to
2848 * flush request stream, since the actual request will
2849 * soon follow.
2851 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
2853 ceph_con_send(&session->s_con, msg);
2857 * Preemptively release a lease we expect to invalidate anyway.
2858 * Pass @inode always, @dentry is optional.
2860 void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
2861 struct dentry *dentry)
2863 struct ceph_dentry_info *di;
2864 struct ceph_mds_session *session;
2865 u32 seq;
2867 BUG_ON(inode == NULL);
2868 BUG_ON(dentry == NULL);
2870 /* is dentry lease valid? */
2871 spin_lock(&dentry->d_lock);
2872 di = ceph_dentry(dentry);
2873 if (!di || !di->lease_session ||
2874 di->lease_session->s_mds < 0 ||
2875 di->lease_gen != di->lease_session->s_cap_gen ||
2876 !time_before(jiffies, dentry->d_time)) {
2877 dout("lease_release inode %p dentry %p -- "
2878 "no lease\n",
2879 inode, dentry);
2880 spin_unlock(&dentry->d_lock);
2881 return;
2884 /* we do have a lease on this dentry; note mds and seq */
2885 session = ceph_get_mds_session(di->lease_session);
2886 seq = di->lease_seq;
2887 __ceph_mdsc_drop_dentry_lease(dentry);
2888 spin_unlock(&dentry->d_lock);
2890 dout("lease_release inode %p dentry %p to mds%d\n",
2891 inode, dentry, session->s_mds);
2892 ceph_mdsc_lease_send_msg(session, inode, dentry,
2893 CEPH_MDS_LEASE_RELEASE, seq);
2894 ceph_put_mds_session(session);
2898 * drop all leases (and dentry refs) in preparation for umount
2900 static void drop_leases(struct ceph_mds_client *mdsc)
2902 int i;
2904 dout("drop_leases\n");
2905 mutex_lock(&mdsc->mutex);
2906 for (i = 0; i < mdsc->max_sessions; i++) {
2907 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2908 if (!s)
2909 continue;
2910 mutex_unlock(&mdsc->mutex);
2911 mutex_lock(&s->s_mutex);
2912 mutex_unlock(&s->s_mutex);
2913 ceph_put_mds_session(s);
2914 mutex_lock(&mdsc->mutex);
2916 mutex_unlock(&mdsc->mutex);
2922 * delayed work -- periodically trim expired leases, renew caps with mds
2924 static void schedule_delayed(struct ceph_mds_client *mdsc)
2926 int delay = 5;
2927 unsigned hz = round_jiffies_relative(HZ * delay);
2928 schedule_delayed_work(&mdsc->delayed_work, hz);
2931 static void delayed_work(struct work_struct *work)
2933 int i;
2934 struct ceph_mds_client *mdsc =
2935 container_of(work, struct ceph_mds_client, delayed_work.work);
2936 int renew_interval;
2937 int renew_caps;
2939 dout("mdsc delayed_work\n");
2940 ceph_check_delayed_caps(mdsc);
2942 mutex_lock(&mdsc->mutex);
2943 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
2944 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
2945 mdsc->last_renew_caps);
2946 if (renew_caps)
2947 mdsc->last_renew_caps = jiffies;
2949 for (i = 0; i < mdsc->max_sessions; i++) {
2950 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2951 if (s == NULL)
2952 continue;
2953 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
2954 dout("resending session close request for mds%d\n",
2955 s->s_mds);
2956 request_close_session(mdsc, s);
2957 ceph_put_mds_session(s);
2958 continue;
2960 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
2961 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
2962 s->s_state = CEPH_MDS_SESSION_HUNG;
2963 pr_info("mds%d hung\n", s->s_mds);
2966 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
2967 /* this mds is failed or recovering, just wait */
2968 ceph_put_mds_session(s);
2969 continue;
2971 mutex_unlock(&mdsc->mutex);
2973 mutex_lock(&s->s_mutex);
2974 if (renew_caps)
2975 send_renew_caps(mdsc, s);
2976 else
2977 ceph_con_keepalive(&s->s_con);
2978 ceph_add_cap_releases(mdsc, s);
2979 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2980 s->s_state == CEPH_MDS_SESSION_HUNG)
2981 ceph_send_cap_releases(mdsc, s);
2982 mutex_unlock(&s->s_mutex);
2983 ceph_put_mds_session(s);
2985 mutex_lock(&mdsc->mutex);
2987 mutex_unlock(&mdsc->mutex);
2989 schedule_delayed(mdsc);
2992 int ceph_mdsc_init(struct ceph_fs_client *fsc)
2995 struct ceph_mds_client *mdsc;
2997 mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS);
2998 if (!mdsc)
2999 return -ENOMEM;
3000 mdsc->fsc = fsc;
3001 fsc->mdsc = mdsc;
3002 mutex_init(&mdsc->mutex);
3003 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
3004 if (mdsc->mdsmap == NULL)
3005 return -ENOMEM;
3007 init_completion(&mdsc->safe_umount_waiters);
3008 init_waitqueue_head(&mdsc->session_close_wq);
3009 INIT_LIST_HEAD(&mdsc->waiting_for_map);
3010 mdsc->sessions = NULL;
3011 mdsc->max_sessions = 0;
3012 mdsc->stopping = 0;
3013 init_rwsem(&mdsc->snap_rwsem);
3014 mdsc->snap_realms = RB_ROOT;
3015 INIT_LIST_HEAD(&mdsc->snap_empty);
3016 spin_lock_init(&mdsc->snap_empty_lock);
3017 mdsc->last_tid = 0;
3018 mdsc->request_tree = RB_ROOT;
3019 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
3020 mdsc->last_renew_caps = jiffies;
3021 INIT_LIST_HEAD(&mdsc->cap_delay_list);
3022 spin_lock_init(&mdsc->cap_delay_lock);
3023 INIT_LIST_HEAD(&mdsc->snap_flush_list);
3024 spin_lock_init(&mdsc->snap_flush_lock);
3025 mdsc->cap_flush_seq = 0;
3026 INIT_LIST_HEAD(&mdsc->cap_dirty);
3027 INIT_LIST_HEAD(&mdsc->cap_dirty_migrating);
3028 mdsc->num_cap_flushing = 0;
3029 spin_lock_init(&mdsc->cap_dirty_lock);
3030 init_waitqueue_head(&mdsc->cap_flushing_wq);
3031 spin_lock_init(&mdsc->dentry_lru_lock);
3032 INIT_LIST_HEAD(&mdsc->dentry_lru);
3034 ceph_caps_init(mdsc);
3035 ceph_adjust_min_caps(mdsc, fsc->min_caps);
3037 return 0;
3041 * Wait for safe replies on open mds requests. If we time out, drop
3042 * all requests from the tree to avoid dangling dentry refs.
3044 static void wait_requests(struct ceph_mds_client *mdsc)
3046 struct ceph_mds_request *req;
3047 struct ceph_fs_client *fsc = mdsc->fsc;
3049 mutex_lock(&mdsc->mutex);
3050 if (__get_oldest_req(mdsc)) {
3051 mutex_unlock(&mdsc->mutex);
3053 dout("wait_requests waiting for requests\n");
3054 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
3055 fsc->client->options->mount_timeout * HZ);
3057 /* tear down remaining requests */
3058 mutex_lock(&mdsc->mutex);
3059 while ((req = __get_oldest_req(mdsc))) {
3060 dout("wait_requests timed out on tid %llu\n",
3061 req->r_tid);
3062 __unregister_request(mdsc, req);
3065 mutex_unlock(&mdsc->mutex);
3066 dout("wait_requests done\n");
3070 * called before mount is ro, and before dentries are torn down.
3071 * (hmm, does this still race with new lookups?)
3073 void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
3075 dout("pre_umount\n");
3076 mdsc->stopping = 1;
3078 drop_leases(mdsc);
3079 ceph_flush_dirty_caps(mdsc);
3080 wait_requests(mdsc);
3083 * wait for reply handlers to drop their request refs and
3084 * their inode/dcache refs
3086 ceph_msgr_flush();
3090 * wait for all write mds requests to flush.
3092 static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
3094 struct ceph_mds_request *req = NULL, *nextreq;
3095 struct rb_node *n;
3097 mutex_lock(&mdsc->mutex);
3098 dout("wait_unsafe_requests want %lld\n", want_tid);
3099 restart:
3100 req = __get_oldest_req(mdsc);
3101 while (req && req->r_tid <= want_tid) {
3102 /* find next request */
3103 n = rb_next(&req->r_node);
3104 if (n)
3105 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
3106 else
3107 nextreq = NULL;
3108 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
3109 /* write op */
3110 ceph_mdsc_get_request(req);
3111 if (nextreq)
3112 ceph_mdsc_get_request(nextreq);
3113 mutex_unlock(&mdsc->mutex);
3114 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
3115 req->r_tid, want_tid);
3116 wait_for_completion(&req->r_safe_completion);
3117 mutex_lock(&mdsc->mutex);
3118 ceph_mdsc_put_request(req);
3119 if (!nextreq)
3120 break; /* next dne before, so we're done! */
3121 if (RB_EMPTY_NODE(&nextreq->r_node)) {
3122 /* next request was removed from tree */
3123 ceph_mdsc_put_request(nextreq);
3124 goto restart;
3126 ceph_mdsc_put_request(nextreq); /* won't go away */
3128 req = nextreq;
3130 mutex_unlock(&mdsc->mutex);
3131 dout("wait_unsafe_requests done\n");
3134 void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
3136 u64 want_tid, want_flush;
3138 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3139 return;
3141 dout("sync\n");
3142 mutex_lock(&mdsc->mutex);
3143 want_tid = mdsc->last_tid;
3144 want_flush = mdsc->cap_flush_seq;
3145 mutex_unlock(&mdsc->mutex);
3146 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
3148 ceph_flush_dirty_caps(mdsc);
3150 wait_unsafe_requests(mdsc, want_tid);
3151 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
3155 * true if all sessions are closed, or we force unmount
3157 bool done_closing_sessions(struct ceph_mds_client *mdsc)
3159 int i, n = 0;
3161 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3162 return true;
3164 mutex_lock(&mdsc->mutex);
3165 for (i = 0; i < mdsc->max_sessions; i++)
3166 if (mdsc->sessions[i])
3167 n++;
3168 mutex_unlock(&mdsc->mutex);
3169 return n == 0;
3173 * called after sb is ro.
3175 void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
3177 struct ceph_mds_session *session;
3178 int i;
3179 struct ceph_fs_client *fsc = mdsc->fsc;
3180 unsigned long timeout = fsc->client->options->mount_timeout * HZ;
3182 dout("close_sessions\n");
3184 /* close sessions */
3185 mutex_lock(&mdsc->mutex);
3186 for (i = 0; i < mdsc->max_sessions; i++) {
3187 session = __ceph_lookup_mds_session(mdsc, i);
3188 if (!session)
3189 continue;
3190 mutex_unlock(&mdsc->mutex);
3191 mutex_lock(&session->s_mutex);
3192 __close_session(mdsc, session);
3193 mutex_unlock(&session->s_mutex);
3194 ceph_put_mds_session(session);
3195 mutex_lock(&mdsc->mutex);
3197 mutex_unlock(&mdsc->mutex);
3199 dout("waiting for sessions to close\n");
3200 wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc),
3201 timeout);
3203 /* tear down remaining sessions */
3204 mutex_lock(&mdsc->mutex);
3205 for (i = 0; i < mdsc->max_sessions; i++) {
3206 if (mdsc->sessions[i]) {
3207 session = get_session(mdsc->sessions[i]);
3208 __unregister_session(mdsc, session);
3209 mutex_unlock(&mdsc->mutex);
3210 mutex_lock(&session->s_mutex);
3211 remove_session_caps(session);
3212 mutex_unlock(&session->s_mutex);
3213 ceph_put_mds_session(session);
3214 mutex_lock(&mdsc->mutex);
3217 WARN_ON(!list_empty(&mdsc->cap_delay_list));
3218 mutex_unlock(&mdsc->mutex);
3220 ceph_cleanup_empty_realms(mdsc);
3222 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3224 dout("stopped\n");
3227 static void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
3229 dout("stop\n");
3230 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3231 if (mdsc->mdsmap)
3232 ceph_mdsmap_destroy(mdsc->mdsmap);
3233 kfree(mdsc->sessions);
3234 ceph_caps_finalize(mdsc);
3237 void ceph_mdsc_destroy(struct ceph_fs_client *fsc)
3239 struct ceph_mds_client *mdsc = fsc->mdsc;
3241 dout("mdsc_destroy %p\n", mdsc);
3242 ceph_mdsc_stop(mdsc);
3244 /* flush out any connection work with references to us */
3245 ceph_msgr_flush();
3247 fsc->mdsc = NULL;
3248 kfree(mdsc);
3249 dout("mdsc_destroy %p done\n", mdsc);
3254 * handle mds map update.
3256 void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3258 u32 epoch;
3259 u32 maplen;
3260 void *p = msg->front.iov_base;
3261 void *end = p + msg->front.iov_len;
3262 struct ceph_mdsmap *newmap, *oldmap;
3263 struct ceph_fsid fsid;
3264 int err = -EINVAL;
3266 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
3267 ceph_decode_copy(&p, &fsid, sizeof(fsid));
3268 if (ceph_check_fsid(mdsc->fsc->client, &fsid) < 0)
3269 return;
3270 epoch = ceph_decode_32(&p);
3271 maplen = ceph_decode_32(&p);
3272 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
3274 /* do we need it? */
3275 ceph_monc_got_mdsmap(&mdsc->fsc->client->monc, epoch);
3276 mutex_lock(&mdsc->mutex);
3277 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
3278 dout("handle_map epoch %u <= our %u\n",
3279 epoch, mdsc->mdsmap->m_epoch);
3280 mutex_unlock(&mdsc->mutex);
3281 return;
3284 newmap = ceph_mdsmap_decode(&p, end);
3285 if (IS_ERR(newmap)) {
3286 err = PTR_ERR(newmap);
3287 goto bad_unlock;
3290 /* swap into place */
3291 if (mdsc->mdsmap) {
3292 oldmap = mdsc->mdsmap;
3293 mdsc->mdsmap = newmap;
3294 check_new_map(mdsc, newmap, oldmap);
3295 ceph_mdsmap_destroy(oldmap);
3296 } else {
3297 mdsc->mdsmap = newmap; /* first mds map */
3299 mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
3301 __wake_requests(mdsc, &mdsc->waiting_for_map);
3303 mutex_unlock(&mdsc->mutex);
3304 schedule_delayed(mdsc);
3305 return;
3307 bad_unlock:
3308 mutex_unlock(&mdsc->mutex);
3309 bad:
3310 pr_err("error decoding mdsmap %d\n", err);
3311 return;
3314 static struct ceph_connection *con_get(struct ceph_connection *con)
3316 struct ceph_mds_session *s = con->private;
3318 if (get_session(s)) {
3319 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
3320 return con;
3322 dout("mdsc con_get %p FAIL\n", s);
3323 return NULL;
3326 static void con_put(struct ceph_connection *con)
3328 struct ceph_mds_session *s = con->private;
3330 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref) - 1);
3331 ceph_put_mds_session(s);
3335 * if the client is unresponsive for long enough, the mds will kill
3336 * the session entirely.
3338 static void peer_reset(struct ceph_connection *con)
3340 struct ceph_mds_session *s = con->private;
3341 struct ceph_mds_client *mdsc = s->s_mdsc;
3343 pr_warning("mds%d closed our session\n", s->s_mds);
3344 send_mds_reconnect(mdsc, s);
3347 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
3349 struct ceph_mds_session *s = con->private;
3350 struct ceph_mds_client *mdsc = s->s_mdsc;
3351 int type = le16_to_cpu(msg->hdr.type);
3353 mutex_lock(&mdsc->mutex);
3354 if (__verify_registered_session(mdsc, s) < 0) {
3355 mutex_unlock(&mdsc->mutex);
3356 goto out;
3358 mutex_unlock(&mdsc->mutex);
3360 switch (type) {
3361 case CEPH_MSG_MDS_MAP:
3362 ceph_mdsc_handle_map(mdsc, msg);
3363 break;
3364 case CEPH_MSG_CLIENT_SESSION:
3365 handle_session(s, msg);
3366 break;
3367 case CEPH_MSG_CLIENT_REPLY:
3368 handle_reply(s, msg);
3369 break;
3370 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
3371 handle_forward(mdsc, s, msg);
3372 break;
3373 case CEPH_MSG_CLIENT_CAPS:
3374 ceph_handle_caps(s, msg);
3375 break;
3376 case CEPH_MSG_CLIENT_SNAP:
3377 ceph_handle_snap(mdsc, s, msg);
3378 break;
3379 case CEPH_MSG_CLIENT_LEASE:
3380 handle_lease(mdsc, s, msg);
3381 break;
3383 default:
3384 pr_err("received unknown message type %d %s\n", type,
3385 ceph_msg_type_name(type));
3387 out:
3388 ceph_msg_put(msg);
3392 * authentication
3394 static int get_authorizer(struct ceph_connection *con,
3395 void **buf, int *len, int *proto,
3396 void **reply_buf, int *reply_len, int force_new)
3398 struct ceph_mds_session *s = con->private;
3399 struct ceph_mds_client *mdsc = s->s_mdsc;
3400 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3401 int ret = 0;
3403 if (force_new && s->s_authorizer) {
3404 ac->ops->destroy_authorizer(ac, s->s_authorizer);
3405 s->s_authorizer = NULL;
3407 if (s->s_authorizer == NULL) {
3408 if (ac->ops->create_authorizer) {
3409 ret = ac->ops->create_authorizer(
3410 ac, CEPH_ENTITY_TYPE_MDS,
3411 &s->s_authorizer,
3412 &s->s_authorizer_buf,
3413 &s->s_authorizer_buf_len,
3414 &s->s_authorizer_reply_buf,
3415 &s->s_authorizer_reply_buf_len);
3416 if (ret)
3417 return ret;
3421 *proto = ac->protocol;
3422 *buf = s->s_authorizer_buf;
3423 *len = s->s_authorizer_buf_len;
3424 *reply_buf = s->s_authorizer_reply_buf;
3425 *reply_len = s->s_authorizer_reply_buf_len;
3426 return 0;
3430 static int verify_authorizer_reply(struct ceph_connection *con, int len)
3432 struct ceph_mds_session *s = con->private;
3433 struct ceph_mds_client *mdsc = s->s_mdsc;
3434 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3436 return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
3439 static int invalidate_authorizer(struct ceph_connection *con)
3441 struct ceph_mds_session *s = con->private;
3442 struct ceph_mds_client *mdsc = s->s_mdsc;
3443 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3445 if (ac->ops->invalidate_authorizer)
3446 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3448 return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
3451 static const struct ceph_connection_operations mds_con_ops = {
3452 .get = con_get,
3453 .put = con_put,
3454 .dispatch = dispatch,
3455 .get_authorizer = get_authorizer,
3456 .verify_authorizer_reply = verify_authorizer_reply,
3457 .invalidate_authorizer = invalidate_authorizer,
3458 .peer_reset = peer_reset,
3461 /* eof */