i2c-eg20t: use i2c_add_numbered_adapter to get a fixed bus number
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / ceph / mds_client.c
blob23ab6a3f1825e85cb839f508535a56cdc0cc55fe
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41 * are no longer valid.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 static 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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_lock);
1019 ci->i_wanted_max_size = 0;
1020 ci->i_requested_max_size = 0;
1021 spin_unlock(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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(&ci->i_ceph_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 spin_unlock(&temp->d_lock);
1499 break;
1500 } else {
1501 pos -= temp->d_name.len;
1502 if (pos < 0) {
1503 spin_unlock(&temp->d_lock);
1504 break;
1506 strncpy(path + pos, temp->d_name.name,
1507 temp->d_name.len);
1509 spin_unlock(&temp->d_lock);
1510 if (pos)
1511 path[--pos] = '/';
1512 temp = temp->d_parent;
1513 if (temp == NULL) {
1514 rcu_read_unlock();
1515 pr_err("build_path corrupt dentry\n");
1516 kfree(path);
1517 return ERR_PTR(-EINVAL);
1520 rcu_read_unlock();
1521 if (pos != 0 || read_seqretry(&rename_lock, seq)) {
1522 pr_err("build_path did not end path lookup where "
1523 "expected, namelen is %d, pos is %d\n", len, pos);
1524 /* presumably this is only possible if racing with a
1525 rename of one of the parent directories (we can not
1526 lock the dentries above us to prevent this, but
1527 retrying should be harmless) */
1528 kfree(path);
1529 goto retry;
1532 *base = ceph_ino(temp->d_inode);
1533 *plen = len;
1534 dout("build_path on %p %d built %llx '%.*s'\n",
1535 dentry, dentry->d_count, *base, len, path);
1536 return path;
1539 static int build_dentry_path(struct dentry *dentry,
1540 const char **ppath, int *ppathlen, u64 *pino,
1541 int *pfreepath)
1543 char *path;
1545 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1546 *pino = ceph_ino(dentry->d_parent->d_inode);
1547 *ppath = dentry->d_name.name;
1548 *ppathlen = dentry->d_name.len;
1549 return 0;
1551 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1552 if (IS_ERR(path))
1553 return PTR_ERR(path);
1554 *ppath = path;
1555 *pfreepath = 1;
1556 return 0;
1559 static int build_inode_path(struct inode *inode,
1560 const char **ppath, int *ppathlen, u64 *pino,
1561 int *pfreepath)
1563 struct dentry *dentry;
1564 char *path;
1566 if (ceph_snap(inode) == CEPH_NOSNAP) {
1567 *pino = ceph_ino(inode);
1568 *ppathlen = 0;
1569 return 0;
1571 dentry = d_find_alias(inode);
1572 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1573 dput(dentry);
1574 if (IS_ERR(path))
1575 return PTR_ERR(path);
1576 *ppath = path;
1577 *pfreepath = 1;
1578 return 0;
1582 * request arguments may be specified via an inode *, a dentry *, or
1583 * an explicit ino+path.
1585 static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1586 const char *rpath, u64 rino,
1587 const char **ppath, int *pathlen,
1588 u64 *ino, int *freepath)
1590 int r = 0;
1592 if (rinode) {
1593 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1594 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1595 ceph_snap(rinode));
1596 } else if (rdentry) {
1597 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1598 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1599 *ppath);
1600 } else if (rpath || rino) {
1601 *ino = rino;
1602 *ppath = rpath;
1603 *pathlen = strlen(rpath);
1604 dout(" path %.*s\n", *pathlen, rpath);
1607 return r;
1611 * called under mdsc->mutex
1613 static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1614 struct ceph_mds_request *req,
1615 int mds)
1617 struct ceph_msg *msg;
1618 struct ceph_mds_request_head *head;
1619 const char *path1 = NULL;
1620 const char *path2 = NULL;
1621 u64 ino1 = 0, ino2 = 0;
1622 int pathlen1 = 0, pathlen2 = 0;
1623 int freepath1 = 0, freepath2 = 0;
1624 int len;
1625 u16 releases;
1626 void *p, *end;
1627 int ret;
1629 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1630 req->r_path1, req->r_ino1.ino,
1631 &path1, &pathlen1, &ino1, &freepath1);
1632 if (ret < 0) {
1633 msg = ERR_PTR(ret);
1634 goto out;
1637 ret = set_request_path_attr(NULL, req->r_old_dentry,
1638 req->r_path2, req->r_ino2.ino,
1639 &path2, &pathlen2, &ino2, &freepath2);
1640 if (ret < 0) {
1641 msg = ERR_PTR(ret);
1642 goto out_free1;
1645 len = sizeof(*head) +
1646 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
1648 /* calculate (max) length for cap releases */
1649 len += sizeof(struct ceph_mds_request_release) *
1650 (!!req->r_inode_drop + !!req->r_dentry_drop +
1651 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1652 if (req->r_dentry_drop)
1653 len += req->r_dentry->d_name.len;
1654 if (req->r_old_dentry_drop)
1655 len += req->r_old_dentry->d_name.len;
1657 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, GFP_NOFS, false);
1658 if (!msg) {
1659 msg = ERR_PTR(-ENOMEM);
1660 goto out_free2;
1663 msg->hdr.tid = cpu_to_le64(req->r_tid);
1665 head = msg->front.iov_base;
1666 p = msg->front.iov_base + sizeof(*head);
1667 end = msg->front.iov_base + msg->front.iov_len;
1669 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1670 head->op = cpu_to_le32(req->r_op);
1671 head->caller_uid = cpu_to_le32(req->r_uid);
1672 head->caller_gid = cpu_to_le32(req->r_gid);
1673 head->args = req->r_args;
1675 ceph_encode_filepath(&p, end, ino1, path1);
1676 ceph_encode_filepath(&p, end, ino2, path2);
1678 /* make note of release offset, in case we need to replay */
1679 req->r_request_release_offset = p - msg->front.iov_base;
1681 /* cap releases */
1682 releases = 0;
1683 if (req->r_inode_drop)
1684 releases += ceph_encode_inode_release(&p,
1685 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1686 mds, req->r_inode_drop, req->r_inode_unless, 0);
1687 if (req->r_dentry_drop)
1688 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1689 mds, req->r_dentry_drop, req->r_dentry_unless);
1690 if (req->r_old_dentry_drop)
1691 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1692 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1693 if (req->r_old_inode_drop)
1694 releases += ceph_encode_inode_release(&p,
1695 req->r_old_dentry->d_inode,
1696 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1697 head->num_releases = cpu_to_le16(releases);
1699 BUG_ON(p > end);
1700 msg->front.iov_len = p - msg->front.iov_base;
1701 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1703 msg->pages = req->r_pages;
1704 msg->nr_pages = req->r_num_pages;
1705 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1706 msg->hdr.data_off = cpu_to_le16(0);
1708 out_free2:
1709 if (freepath2)
1710 kfree((char *)path2);
1711 out_free1:
1712 if (freepath1)
1713 kfree((char *)path1);
1714 out:
1715 return msg;
1719 * called under mdsc->mutex if error, under no mutex if
1720 * success.
1722 static void complete_request(struct ceph_mds_client *mdsc,
1723 struct ceph_mds_request *req)
1725 if (req->r_callback)
1726 req->r_callback(mdsc, req);
1727 else
1728 complete_all(&req->r_completion);
1732 * called under mdsc->mutex
1734 static int __prepare_send_request(struct ceph_mds_client *mdsc,
1735 struct ceph_mds_request *req,
1736 int mds)
1738 struct ceph_mds_request_head *rhead;
1739 struct ceph_msg *msg;
1740 int flags = 0;
1742 req->r_attempts++;
1743 if (req->r_inode) {
1744 struct ceph_cap *cap =
1745 ceph_get_cap_for_mds(ceph_inode(req->r_inode), mds);
1747 if (cap)
1748 req->r_sent_on_mseq = cap->mseq;
1749 else
1750 req->r_sent_on_mseq = -1;
1752 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1753 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1755 if (req->r_got_unsafe) {
1757 * Replay. Do not regenerate message (and rebuild
1758 * paths, etc.); just use the original message.
1759 * Rebuilding paths will break for renames because
1760 * d_move mangles the src name.
1762 msg = req->r_request;
1763 rhead = msg->front.iov_base;
1765 flags = le32_to_cpu(rhead->flags);
1766 flags |= CEPH_MDS_FLAG_REPLAY;
1767 rhead->flags = cpu_to_le32(flags);
1769 if (req->r_target_inode)
1770 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1772 rhead->num_retry = req->r_attempts - 1;
1774 /* remove cap/dentry releases from message */
1775 rhead->num_releases = 0;
1776 msg->hdr.front_len = cpu_to_le32(req->r_request_release_offset);
1777 msg->front.iov_len = req->r_request_release_offset;
1778 return 0;
1781 if (req->r_request) {
1782 ceph_msg_put(req->r_request);
1783 req->r_request = NULL;
1785 msg = create_request_message(mdsc, req, mds);
1786 if (IS_ERR(msg)) {
1787 req->r_err = PTR_ERR(msg);
1788 complete_request(mdsc, req);
1789 return PTR_ERR(msg);
1791 req->r_request = msg;
1793 rhead = msg->front.iov_base;
1794 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1795 if (req->r_got_unsafe)
1796 flags |= CEPH_MDS_FLAG_REPLAY;
1797 if (req->r_locked_dir)
1798 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1799 rhead->flags = cpu_to_le32(flags);
1800 rhead->num_fwd = req->r_num_fwd;
1801 rhead->num_retry = req->r_attempts - 1;
1802 rhead->ino = 0;
1804 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1805 return 0;
1809 * send request, or put it on the appropriate wait list.
1811 static int __do_request(struct ceph_mds_client *mdsc,
1812 struct ceph_mds_request *req)
1814 struct ceph_mds_session *session = NULL;
1815 int mds = -1;
1816 int err = -EAGAIN;
1818 if (req->r_err || req->r_got_result)
1819 goto out;
1821 if (req->r_timeout &&
1822 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1823 dout("do_request timed out\n");
1824 err = -EIO;
1825 goto finish;
1828 put_request_session(req);
1830 mds = __choose_mds(mdsc, req);
1831 if (mds < 0 ||
1832 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1833 dout("do_request no mds or not active, waiting for map\n");
1834 list_add(&req->r_wait, &mdsc->waiting_for_map);
1835 goto out;
1838 /* get, open session */
1839 session = __ceph_lookup_mds_session(mdsc, mds);
1840 if (!session) {
1841 session = register_session(mdsc, mds);
1842 if (IS_ERR(session)) {
1843 err = PTR_ERR(session);
1844 goto finish;
1847 req->r_session = get_session(session);
1849 dout("do_request mds%d session %p state %s\n", mds, session,
1850 session_state_name(session->s_state));
1851 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
1852 session->s_state != CEPH_MDS_SESSION_HUNG) {
1853 if (session->s_state == CEPH_MDS_SESSION_NEW ||
1854 session->s_state == CEPH_MDS_SESSION_CLOSING)
1855 __open_session(mdsc, session);
1856 list_add(&req->r_wait, &session->s_waiting);
1857 goto out_session;
1860 /* send request */
1861 req->r_resend_mds = -1; /* forget any previous mds hint */
1863 if (req->r_request_started == 0) /* note request start time */
1864 req->r_request_started = jiffies;
1866 err = __prepare_send_request(mdsc, req, mds);
1867 if (!err) {
1868 ceph_msg_get(req->r_request);
1869 ceph_con_send(&session->s_con, req->r_request);
1872 out_session:
1873 ceph_put_mds_session(session);
1874 out:
1875 return err;
1877 finish:
1878 req->r_err = err;
1879 complete_request(mdsc, req);
1880 goto out;
1884 * called under mdsc->mutex
1886 static void __wake_requests(struct ceph_mds_client *mdsc,
1887 struct list_head *head)
1889 struct ceph_mds_request *req, *nreq;
1891 list_for_each_entry_safe(req, nreq, head, r_wait) {
1892 list_del_init(&req->r_wait);
1893 __do_request(mdsc, req);
1898 * Wake up threads with requests pending for @mds, so that they can
1899 * resubmit their requests to a possibly different mds.
1901 static void kick_requests(struct ceph_mds_client *mdsc, int mds)
1903 struct ceph_mds_request *req;
1904 struct rb_node *p;
1906 dout("kick_requests mds%d\n", mds);
1907 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
1908 req = rb_entry(p, struct ceph_mds_request, r_node);
1909 if (req->r_got_unsafe)
1910 continue;
1911 if (req->r_session &&
1912 req->r_session->s_mds == mds) {
1913 dout(" kicking tid %llu\n", req->r_tid);
1914 __do_request(mdsc, req);
1919 void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
1920 struct ceph_mds_request *req)
1922 dout("submit_request on %p\n", req);
1923 mutex_lock(&mdsc->mutex);
1924 __register_request(mdsc, req, NULL);
1925 __do_request(mdsc, req);
1926 mutex_unlock(&mdsc->mutex);
1930 * Synchrously perform an mds request. Take care of all of the
1931 * session setup, forwarding, retry details.
1933 int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
1934 struct inode *dir,
1935 struct ceph_mds_request *req)
1937 int err;
1939 dout("do_request on %p\n", req);
1941 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
1942 if (req->r_inode)
1943 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
1944 if (req->r_locked_dir)
1945 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
1946 if (req->r_old_dentry)
1947 ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
1948 CEPH_CAP_PIN);
1950 /* issue */
1951 mutex_lock(&mdsc->mutex);
1952 __register_request(mdsc, req, dir);
1953 __do_request(mdsc, req);
1955 if (req->r_err) {
1956 err = req->r_err;
1957 __unregister_request(mdsc, req);
1958 dout("do_request early error %d\n", err);
1959 goto out;
1962 /* wait */
1963 mutex_unlock(&mdsc->mutex);
1964 dout("do_request waiting\n");
1965 if (req->r_timeout) {
1966 err = (long)wait_for_completion_killable_timeout(
1967 &req->r_completion, req->r_timeout);
1968 if (err == 0)
1969 err = -EIO;
1970 } else {
1971 err = wait_for_completion_killable(&req->r_completion);
1973 dout("do_request waited, got %d\n", err);
1974 mutex_lock(&mdsc->mutex);
1976 /* only abort if we didn't race with a real reply */
1977 if (req->r_got_result) {
1978 err = le32_to_cpu(req->r_reply_info.head->result);
1979 } else if (err < 0) {
1980 dout("aborted request %lld with %d\n", req->r_tid, err);
1983 * ensure we aren't running concurrently with
1984 * ceph_fill_trace or ceph_readdir_prepopulate, which
1985 * rely on locks (dir mutex) held by our caller.
1987 mutex_lock(&req->r_fill_mutex);
1988 req->r_err = err;
1989 req->r_aborted = true;
1990 mutex_unlock(&req->r_fill_mutex);
1992 if (req->r_locked_dir &&
1993 (req->r_op & CEPH_MDS_OP_WRITE))
1994 ceph_invalidate_dir_request(req);
1995 } else {
1996 err = req->r_err;
1999 out:
2000 mutex_unlock(&mdsc->mutex);
2001 dout("do_request %p done, result %d\n", req, err);
2002 return err;
2006 * Invalidate dir D_COMPLETE, dentry lease state on an aborted MDS
2007 * namespace request.
2009 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
2011 struct inode *inode = req->r_locked_dir;
2012 struct ceph_inode_info *ci = ceph_inode(inode);
2014 dout("invalidate_dir_request %p (D_COMPLETE, lease(s))\n", inode);
2015 spin_lock(&ci->i_ceph_lock);
2016 ceph_dir_clear_complete(inode);
2017 ci->i_release_count++;
2018 spin_unlock(&ci->i_ceph_lock);
2020 if (req->r_dentry)
2021 ceph_invalidate_dentry_lease(req->r_dentry);
2022 if (req->r_old_dentry)
2023 ceph_invalidate_dentry_lease(req->r_old_dentry);
2027 * Handle mds reply.
2029 * We take the session mutex and parse and process the reply immediately.
2030 * This preserves the logical ordering of replies, capabilities, etc., sent
2031 * by the MDS as they are applied to our local cache.
2033 static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
2035 struct ceph_mds_client *mdsc = session->s_mdsc;
2036 struct ceph_mds_request *req;
2037 struct ceph_mds_reply_head *head = msg->front.iov_base;
2038 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
2039 u64 tid;
2040 int err, result;
2041 int mds = session->s_mds;
2043 if (msg->front.iov_len < sizeof(*head)) {
2044 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
2045 ceph_msg_dump(msg);
2046 return;
2049 /* get request, session */
2050 tid = le64_to_cpu(msg->hdr.tid);
2051 mutex_lock(&mdsc->mutex);
2052 req = __lookup_request(mdsc, tid);
2053 if (!req) {
2054 dout("handle_reply on unknown tid %llu\n", tid);
2055 mutex_unlock(&mdsc->mutex);
2056 return;
2058 dout("handle_reply %p\n", req);
2060 /* correct session? */
2061 if (req->r_session != session) {
2062 pr_err("mdsc_handle_reply got %llu on session mds%d"
2063 " not mds%d\n", tid, session->s_mds,
2064 req->r_session ? req->r_session->s_mds : -1);
2065 mutex_unlock(&mdsc->mutex);
2066 goto out;
2069 /* dup? */
2070 if ((req->r_got_unsafe && !head->safe) ||
2071 (req->r_got_safe && head->safe)) {
2072 pr_warning("got a dup %s reply on %llu from mds%d\n",
2073 head->safe ? "safe" : "unsafe", tid, mds);
2074 mutex_unlock(&mdsc->mutex);
2075 goto out;
2077 if (req->r_got_safe && !head->safe) {
2078 pr_warning("got unsafe after safe on %llu from mds%d\n",
2079 tid, mds);
2080 mutex_unlock(&mdsc->mutex);
2081 goto out;
2084 result = le32_to_cpu(head->result);
2087 * Handle an ESTALE
2088 * if we're not talking to the authority, send to them
2089 * if the authority has changed while we weren't looking,
2090 * send to new authority
2091 * Otherwise we just have to return an ESTALE
2093 if (result == -ESTALE) {
2094 dout("got ESTALE on request %llu", req->r_tid);
2095 if (!req->r_inode) {
2096 /* do nothing; not an authority problem */
2097 } else if (req->r_direct_mode != USE_AUTH_MDS) {
2098 dout("not using auth, setting for that now");
2099 req->r_direct_mode = USE_AUTH_MDS;
2100 __do_request(mdsc, req);
2101 mutex_unlock(&mdsc->mutex);
2102 goto out;
2103 } else {
2104 struct ceph_inode_info *ci = ceph_inode(req->r_inode);
2105 struct ceph_cap *cap = NULL;
2107 if (req->r_session)
2108 cap = ceph_get_cap_for_mds(ci,
2109 req->r_session->s_mds);
2111 dout("already using auth");
2112 if ((!cap || cap != ci->i_auth_cap) ||
2113 (cap->mseq != req->r_sent_on_mseq)) {
2114 dout("but cap changed, so resending");
2115 __do_request(mdsc, req);
2116 mutex_unlock(&mdsc->mutex);
2117 goto out;
2120 dout("have to return ESTALE on request %llu", req->r_tid);
2124 if (head->safe) {
2125 req->r_got_safe = true;
2126 __unregister_request(mdsc, req);
2127 complete_all(&req->r_safe_completion);
2129 if (req->r_got_unsafe) {
2131 * We already handled the unsafe response, now do the
2132 * cleanup. No need to examine the response; the MDS
2133 * doesn't include any result info in the safe
2134 * response. And even if it did, there is nothing
2135 * useful we could do with a revised return value.
2137 dout("got safe reply %llu, mds%d\n", tid, mds);
2138 list_del_init(&req->r_unsafe_item);
2140 /* last unsafe request during umount? */
2141 if (mdsc->stopping && !__get_oldest_req(mdsc))
2142 complete_all(&mdsc->safe_umount_waiters);
2143 mutex_unlock(&mdsc->mutex);
2144 goto out;
2146 } else {
2147 req->r_got_unsafe = true;
2148 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
2151 dout("handle_reply tid %lld result %d\n", tid, result);
2152 rinfo = &req->r_reply_info;
2153 err = parse_reply_info(msg, rinfo, session->s_con.peer_features);
2154 mutex_unlock(&mdsc->mutex);
2156 mutex_lock(&session->s_mutex);
2157 if (err < 0) {
2158 pr_err("mdsc_handle_reply got corrupt reply mds%d(tid:%lld)\n", mds, tid);
2159 ceph_msg_dump(msg);
2160 goto out_err;
2163 /* snap trace */
2164 if (rinfo->snapblob_len) {
2165 down_write(&mdsc->snap_rwsem);
2166 ceph_update_snap_trace(mdsc, rinfo->snapblob,
2167 rinfo->snapblob + rinfo->snapblob_len,
2168 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
2169 downgrade_write(&mdsc->snap_rwsem);
2170 } else {
2171 down_read(&mdsc->snap_rwsem);
2174 /* insert trace into our cache */
2175 mutex_lock(&req->r_fill_mutex);
2176 err = ceph_fill_trace(mdsc->fsc->sb, req, req->r_session);
2177 if (err == 0) {
2178 if (result == 0 && req->r_op != CEPH_MDS_OP_GETFILELOCK &&
2179 rinfo->dir_nr)
2180 ceph_readdir_prepopulate(req, req->r_session);
2181 ceph_unreserve_caps(mdsc, &req->r_caps_reservation);
2183 mutex_unlock(&req->r_fill_mutex);
2185 up_read(&mdsc->snap_rwsem);
2186 out_err:
2187 mutex_lock(&mdsc->mutex);
2188 if (!req->r_aborted) {
2189 if (err) {
2190 req->r_err = err;
2191 } else {
2192 req->r_reply = msg;
2193 ceph_msg_get(msg);
2194 req->r_got_result = true;
2196 } else {
2197 dout("reply arrived after request %lld was aborted\n", tid);
2199 mutex_unlock(&mdsc->mutex);
2201 ceph_add_cap_releases(mdsc, req->r_session);
2202 mutex_unlock(&session->s_mutex);
2204 /* kick calling process */
2205 complete_request(mdsc, req);
2206 out:
2207 ceph_mdsc_put_request(req);
2208 return;
2214 * handle mds notification that our request has been forwarded.
2216 static void handle_forward(struct ceph_mds_client *mdsc,
2217 struct ceph_mds_session *session,
2218 struct ceph_msg *msg)
2220 struct ceph_mds_request *req;
2221 u64 tid = le64_to_cpu(msg->hdr.tid);
2222 u32 next_mds;
2223 u32 fwd_seq;
2224 int err = -EINVAL;
2225 void *p = msg->front.iov_base;
2226 void *end = p + msg->front.iov_len;
2228 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
2229 next_mds = ceph_decode_32(&p);
2230 fwd_seq = ceph_decode_32(&p);
2232 mutex_lock(&mdsc->mutex);
2233 req = __lookup_request(mdsc, tid);
2234 if (!req) {
2235 dout("forward tid %llu to mds%d - req dne\n", tid, next_mds);
2236 goto out; /* dup reply? */
2239 if (req->r_aborted) {
2240 dout("forward tid %llu aborted, unregistering\n", tid);
2241 __unregister_request(mdsc, req);
2242 } else if (fwd_seq <= req->r_num_fwd) {
2243 dout("forward tid %llu to mds%d - old seq %d <= %d\n",
2244 tid, next_mds, req->r_num_fwd, fwd_seq);
2245 } else {
2246 /* resend. forward race not possible; mds would drop */
2247 dout("forward tid %llu to mds%d (we resend)\n", tid, next_mds);
2248 BUG_ON(req->r_err);
2249 BUG_ON(req->r_got_result);
2250 req->r_num_fwd = fwd_seq;
2251 req->r_resend_mds = next_mds;
2252 put_request_session(req);
2253 __do_request(mdsc, req);
2255 ceph_mdsc_put_request(req);
2256 out:
2257 mutex_unlock(&mdsc->mutex);
2258 return;
2260 bad:
2261 pr_err("mdsc_handle_forward decode error err=%d\n", err);
2265 * handle a mds session control message
2267 static void handle_session(struct ceph_mds_session *session,
2268 struct ceph_msg *msg)
2270 struct ceph_mds_client *mdsc = session->s_mdsc;
2271 u32 op;
2272 u64 seq;
2273 int mds = session->s_mds;
2274 struct ceph_mds_session_head *h = msg->front.iov_base;
2275 int wake = 0;
2277 /* decode */
2278 if (msg->front.iov_len != sizeof(*h))
2279 goto bad;
2280 op = le32_to_cpu(h->op);
2281 seq = le64_to_cpu(h->seq);
2283 mutex_lock(&mdsc->mutex);
2284 if (op == CEPH_SESSION_CLOSE)
2285 __unregister_session(mdsc, session);
2286 /* FIXME: this ttl calculation is generous */
2287 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2288 mutex_unlock(&mdsc->mutex);
2290 mutex_lock(&session->s_mutex);
2292 dout("handle_session mds%d %s %p state %s seq %llu\n",
2293 mds, ceph_session_op_name(op), session,
2294 session_state_name(session->s_state), seq);
2296 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2297 session->s_state = CEPH_MDS_SESSION_OPEN;
2298 pr_info("mds%d came back\n", session->s_mds);
2301 switch (op) {
2302 case CEPH_SESSION_OPEN:
2303 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2304 pr_info("mds%d reconnect success\n", session->s_mds);
2305 session->s_state = CEPH_MDS_SESSION_OPEN;
2306 renewed_caps(mdsc, session, 0);
2307 wake = 1;
2308 if (mdsc->stopping)
2309 __close_session(mdsc, session);
2310 break;
2312 case CEPH_SESSION_RENEWCAPS:
2313 if (session->s_renew_seq == seq)
2314 renewed_caps(mdsc, session, 1);
2315 break;
2317 case CEPH_SESSION_CLOSE:
2318 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2319 pr_info("mds%d reconnect denied\n", session->s_mds);
2320 remove_session_caps(session);
2321 wake = 1; /* for good measure */
2322 wake_up_all(&mdsc->session_close_wq);
2323 kick_requests(mdsc, mds);
2324 break;
2326 case CEPH_SESSION_STALE:
2327 pr_info("mds%d caps went stale, renewing\n",
2328 session->s_mds);
2329 spin_lock(&session->s_cap_lock);
2330 session->s_cap_gen++;
2331 session->s_cap_ttl = 0;
2332 spin_unlock(&session->s_cap_lock);
2333 send_renew_caps(mdsc, session);
2334 break;
2336 case CEPH_SESSION_RECALL_STATE:
2337 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2338 break;
2340 default:
2341 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2342 WARN_ON(1);
2345 mutex_unlock(&session->s_mutex);
2346 if (wake) {
2347 mutex_lock(&mdsc->mutex);
2348 __wake_requests(mdsc, &session->s_waiting);
2349 mutex_unlock(&mdsc->mutex);
2351 return;
2353 bad:
2354 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2355 (int)msg->front.iov_len);
2356 ceph_msg_dump(msg);
2357 return;
2362 * called under session->mutex.
2364 static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2365 struct ceph_mds_session *session)
2367 struct ceph_mds_request *req, *nreq;
2368 int err;
2370 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2372 mutex_lock(&mdsc->mutex);
2373 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2374 err = __prepare_send_request(mdsc, req, session->s_mds);
2375 if (!err) {
2376 ceph_msg_get(req->r_request);
2377 ceph_con_send(&session->s_con, req->r_request);
2380 mutex_unlock(&mdsc->mutex);
2384 * Encode information about a cap for a reconnect with the MDS.
2386 static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2387 void *arg)
2389 union {
2390 struct ceph_mds_cap_reconnect v2;
2391 struct ceph_mds_cap_reconnect_v1 v1;
2392 } rec;
2393 size_t reclen;
2394 struct ceph_inode_info *ci;
2395 struct ceph_reconnect_state *recon_state = arg;
2396 struct ceph_pagelist *pagelist = recon_state->pagelist;
2397 char *path;
2398 int pathlen, err;
2399 u64 pathbase;
2400 struct dentry *dentry;
2402 ci = cap->ci;
2404 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2405 inode, ceph_vinop(inode), cap, cap->cap_id,
2406 ceph_cap_string(cap->issued));
2407 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2408 if (err)
2409 return err;
2411 dentry = d_find_alias(inode);
2412 if (dentry) {
2413 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2414 if (IS_ERR(path)) {
2415 err = PTR_ERR(path);
2416 goto out_dput;
2418 } else {
2419 path = NULL;
2420 pathlen = 0;
2422 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2423 if (err)
2424 goto out_free;
2426 spin_lock(&ci->i_ceph_lock);
2427 cap->seq = 0; /* reset cap seq */
2428 cap->issue_seq = 0; /* and issue_seq */
2430 if (recon_state->flock) {
2431 rec.v2.cap_id = cpu_to_le64(cap->cap_id);
2432 rec.v2.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2433 rec.v2.issued = cpu_to_le32(cap->issued);
2434 rec.v2.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2435 rec.v2.pathbase = cpu_to_le64(pathbase);
2436 rec.v2.flock_len = 0;
2437 reclen = sizeof(rec.v2);
2438 } else {
2439 rec.v1.cap_id = cpu_to_le64(cap->cap_id);
2440 rec.v1.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2441 rec.v1.issued = cpu_to_le32(cap->issued);
2442 rec.v1.size = cpu_to_le64(inode->i_size);
2443 ceph_encode_timespec(&rec.v1.mtime, &inode->i_mtime);
2444 ceph_encode_timespec(&rec.v1.atime, &inode->i_atime);
2445 rec.v1.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2446 rec.v1.pathbase = cpu_to_le64(pathbase);
2447 reclen = sizeof(rec.v1);
2449 spin_unlock(&ci->i_ceph_lock);
2451 if (recon_state->flock) {
2452 int num_fcntl_locks, num_flock_locks;
2453 struct ceph_pagelist_cursor trunc_point;
2455 ceph_pagelist_set_cursor(pagelist, &trunc_point);
2456 do {
2457 lock_flocks();
2458 ceph_count_locks(inode, &num_fcntl_locks,
2459 &num_flock_locks);
2460 rec.v2.flock_len = (2*sizeof(u32) +
2461 (num_fcntl_locks+num_flock_locks) *
2462 sizeof(struct ceph_filelock));
2463 unlock_flocks();
2465 /* pre-alloc pagelist */
2466 ceph_pagelist_truncate(pagelist, &trunc_point);
2467 err = ceph_pagelist_append(pagelist, &rec, reclen);
2468 if (!err)
2469 err = ceph_pagelist_reserve(pagelist,
2470 rec.v2.flock_len);
2472 /* encode locks */
2473 if (!err) {
2474 lock_flocks();
2475 err = ceph_encode_locks(inode,
2476 pagelist,
2477 num_fcntl_locks,
2478 num_flock_locks);
2479 unlock_flocks();
2481 } while (err == -ENOSPC);
2482 } else {
2483 err = ceph_pagelist_append(pagelist, &rec, reclen);
2486 out_free:
2487 kfree(path);
2488 out_dput:
2489 dput(dentry);
2490 return err;
2495 * If an MDS fails and recovers, clients need to reconnect in order to
2496 * reestablish shared state. This includes all caps issued through
2497 * this session _and_ the snap_realm hierarchy. Because it's not
2498 * clear which snap realms the mds cares about, we send everything we
2499 * know about.. that ensures we'll then get any new info the
2500 * recovering MDS might have.
2502 * This is a relatively heavyweight operation, but it's rare.
2504 * called with mdsc->mutex held.
2506 static void send_mds_reconnect(struct ceph_mds_client *mdsc,
2507 struct ceph_mds_session *session)
2509 struct ceph_msg *reply;
2510 struct rb_node *p;
2511 int mds = session->s_mds;
2512 int err = -ENOMEM;
2513 struct ceph_pagelist *pagelist;
2514 struct ceph_reconnect_state recon_state;
2516 pr_info("mds%d reconnect start\n", mds);
2518 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2519 if (!pagelist)
2520 goto fail_nopagelist;
2521 ceph_pagelist_init(pagelist);
2523 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, GFP_NOFS, false);
2524 if (!reply)
2525 goto fail_nomsg;
2527 mutex_lock(&session->s_mutex);
2528 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2529 session->s_seq = 0;
2531 ceph_con_open(&session->s_con,
2532 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2534 /* replay unsafe requests */
2535 replay_unsafe_requests(mdsc, session);
2537 down_read(&mdsc->snap_rwsem);
2539 dout("session %p state %s\n", session,
2540 session_state_name(session->s_state));
2542 /* drop old cap expires; we're about to reestablish that state */
2543 discard_cap_releases(mdsc, session);
2545 /* traverse this session's caps */
2546 err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
2547 if (err)
2548 goto fail;
2550 recon_state.pagelist = pagelist;
2551 recon_state.flock = session->s_con.peer_features & CEPH_FEATURE_FLOCK;
2552 err = iterate_session_caps(session, encode_caps_cb, &recon_state);
2553 if (err < 0)
2554 goto fail;
2557 * snaprealms. we provide mds with the ino, seq (version), and
2558 * parent for all of our realms. If the mds has any newer info,
2559 * it will tell us.
2561 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2562 struct ceph_snap_realm *realm =
2563 rb_entry(p, struct ceph_snap_realm, node);
2564 struct ceph_mds_snaprealm_reconnect sr_rec;
2566 dout(" adding snap realm %llx seq %lld parent %llx\n",
2567 realm->ino, realm->seq, realm->parent_ino);
2568 sr_rec.ino = cpu_to_le64(realm->ino);
2569 sr_rec.seq = cpu_to_le64(realm->seq);
2570 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2571 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2572 if (err)
2573 goto fail;
2576 reply->pagelist = pagelist;
2577 if (recon_state.flock)
2578 reply->hdr.version = cpu_to_le16(2);
2579 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2580 reply->nr_pages = calc_pages_for(0, pagelist->length);
2581 ceph_con_send(&session->s_con, reply);
2583 mutex_unlock(&session->s_mutex);
2585 mutex_lock(&mdsc->mutex);
2586 __wake_requests(mdsc, &session->s_waiting);
2587 mutex_unlock(&mdsc->mutex);
2589 up_read(&mdsc->snap_rwsem);
2590 return;
2592 fail:
2593 ceph_msg_put(reply);
2594 up_read(&mdsc->snap_rwsem);
2595 mutex_unlock(&session->s_mutex);
2596 fail_nomsg:
2597 ceph_pagelist_release(pagelist);
2598 kfree(pagelist);
2599 fail_nopagelist:
2600 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
2601 return;
2606 * compare old and new mdsmaps, kicking requests
2607 * and closing out old connections as necessary
2609 * called under mdsc->mutex.
2611 static void check_new_map(struct ceph_mds_client *mdsc,
2612 struct ceph_mdsmap *newmap,
2613 struct ceph_mdsmap *oldmap)
2615 int i;
2616 int oldstate, newstate;
2617 struct ceph_mds_session *s;
2619 dout("check_new_map new %u old %u\n",
2620 newmap->m_epoch, oldmap->m_epoch);
2622 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2623 if (mdsc->sessions[i] == NULL)
2624 continue;
2625 s = mdsc->sessions[i];
2626 oldstate = ceph_mdsmap_get_state(oldmap, i);
2627 newstate = ceph_mdsmap_get_state(newmap, i);
2629 dout("check_new_map mds%d state %s%s -> %s%s (session %s)\n",
2630 i, ceph_mds_state_name(oldstate),
2631 ceph_mdsmap_is_laggy(oldmap, i) ? " (laggy)" : "",
2632 ceph_mds_state_name(newstate),
2633 ceph_mdsmap_is_laggy(newmap, i) ? " (laggy)" : "",
2634 session_state_name(s->s_state));
2636 if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
2637 ceph_mdsmap_get_addr(newmap, i),
2638 sizeof(struct ceph_entity_addr))) {
2639 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2640 /* the session never opened, just close it
2641 * out now */
2642 __wake_requests(mdsc, &s->s_waiting);
2643 __unregister_session(mdsc, s);
2644 } else {
2645 /* just close it */
2646 mutex_unlock(&mdsc->mutex);
2647 mutex_lock(&s->s_mutex);
2648 mutex_lock(&mdsc->mutex);
2649 ceph_con_close(&s->s_con);
2650 mutex_unlock(&s->s_mutex);
2651 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2654 /* kick any requests waiting on the recovering mds */
2655 kick_requests(mdsc, i);
2656 } else if (oldstate == newstate) {
2657 continue; /* nothing new with this mds */
2661 * send reconnect?
2663 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2664 newstate >= CEPH_MDS_STATE_RECONNECT) {
2665 mutex_unlock(&mdsc->mutex);
2666 send_mds_reconnect(mdsc, s);
2667 mutex_lock(&mdsc->mutex);
2671 * kick request on any mds that has gone active.
2673 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2674 newstate >= CEPH_MDS_STATE_ACTIVE) {
2675 if (oldstate != CEPH_MDS_STATE_CREATING &&
2676 oldstate != CEPH_MDS_STATE_STARTING)
2677 pr_info("mds%d recovery completed\n", s->s_mds);
2678 kick_requests(mdsc, i);
2679 ceph_kick_flushing_caps(mdsc, s);
2680 wake_up_session_caps(s, 1);
2684 for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
2685 s = mdsc->sessions[i];
2686 if (!s)
2687 continue;
2688 if (!ceph_mdsmap_is_laggy(newmap, i))
2689 continue;
2690 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2691 s->s_state == CEPH_MDS_SESSION_HUNG ||
2692 s->s_state == CEPH_MDS_SESSION_CLOSING) {
2693 dout(" connecting to export targets of laggy mds%d\n",
2695 __open_export_target_sessions(mdsc, s);
2703 * leases
2707 * caller must hold session s_mutex, dentry->d_lock
2709 void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2711 struct ceph_dentry_info *di = ceph_dentry(dentry);
2713 ceph_put_mds_session(di->lease_session);
2714 di->lease_session = NULL;
2717 static void handle_lease(struct ceph_mds_client *mdsc,
2718 struct ceph_mds_session *session,
2719 struct ceph_msg *msg)
2721 struct super_block *sb = mdsc->fsc->sb;
2722 struct inode *inode;
2723 struct dentry *parent, *dentry;
2724 struct ceph_dentry_info *di;
2725 int mds = session->s_mds;
2726 struct ceph_mds_lease *h = msg->front.iov_base;
2727 u32 seq;
2728 struct ceph_vino vino;
2729 struct qstr dname;
2730 int release = 0;
2732 dout("handle_lease from mds%d\n", mds);
2734 /* decode */
2735 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2736 goto bad;
2737 vino.ino = le64_to_cpu(h->ino);
2738 vino.snap = CEPH_NOSNAP;
2739 seq = le32_to_cpu(h->seq);
2740 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2741 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2742 if (dname.len != get_unaligned_le32(h+1))
2743 goto bad;
2745 mutex_lock(&session->s_mutex);
2746 session->s_seq++;
2748 /* lookup inode */
2749 inode = ceph_find_inode(sb, vino);
2750 dout("handle_lease %s, ino %llx %p %.*s\n",
2751 ceph_lease_op_name(h->action), vino.ino, inode,
2752 dname.len, dname.name);
2753 if (inode == NULL) {
2754 dout("handle_lease no inode %llx\n", vino.ino);
2755 goto release;
2758 /* dentry */
2759 parent = d_find_alias(inode);
2760 if (!parent) {
2761 dout("no parent dentry on inode %p\n", inode);
2762 WARN_ON(1);
2763 goto release; /* hrm... */
2765 dname.hash = full_name_hash(dname.name, dname.len);
2766 dentry = d_lookup(parent, &dname);
2767 dput(parent);
2768 if (!dentry)
2769 goto release;
2771 spin_lock(&dentry->d_lock);
2772 di = ceph_dentry(dentry);
2773 switch (h->action) {
2774 case CEPH_MDS_LEASE_REVOKE:
2775 if (di->lease_session == session) {
2776 if (ceph_seq_cmp(di->lease_seq, seq) > 0)
2777 h->seq = cpu_to_le32(di->lease_seq);
2778 __ceph_mdsc_drop_dentry_lease(dentry);
2780 release = 1;
2781 break;
2783 case CEPH_MDS_LEASE_RENEW:
2784 if (di->lease_session == session &&
2785 di->lease_gen == session->s_cap_gen &&
2786 di->lease_renew_from &&
2787 di->lease_renew_after == 0) {
2788 unsigned long duration =
2789 le32_to_cpu(h->duration_ms) * HZ / 1000;
2791 di->lease_seq = seq;
2792 dentry->d_time = di->lease_renew_from + duration;
2793 di->lease_renew_after = di->lease_renew_from +
2794 (duration >> 1);
2795 di->lease_renew_from = 0;
2797 break;
2799 spin_unlock(&dentry->d_lock);
2800 dput(dentry);
2802 if (!release)
2803 goto out;
2805 release:
2806 /* let's just reuse the same message */
2807 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2808 ceph_msg_get(msg);
2809 ceph_con_send(&session->s_con, msg);
2811 out:
2812 iput(inode);
2813 mutex_unlock(&session->s_mutex);
2814 return;
2816 bad:
2817 pr_err("corrupt lease message\n");
2818 ceph_msg_dump(msg);
2821 void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
2822 struct inode *inode,
2823 struct dentry *dentry, char action,
2824 u32 seq)
2826 struct ceph_msg *msg;
2827 struct ceph_mds_lease *lease;
2828 int len = sizeof(*lease) + sizeof(u32);
2829 int dnamelen = 0;
2831 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
2832 inode, dentry, ceph_lease_op_name(action), session->s_mds);
2833 dnamelen = dentry->d_name.len;
2834 len += dnamelen;
2836 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, GFP_NOFS, false);
2837 if (!msg)
2838 return;
2839 lease = msg->front.iov_base;
2840 lease->action = action;
2841 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
2842 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
2843 lease->seq = cpu_to_le32(seq);
2844 put_unaligned_le32(dnamelen, lease + 1);
2845 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
2848 * if this is a preemptive lease RELEASE, no need to
2849 * flush request stream, since the actual request will
2850 * soon follow.
2852 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
2854 ceph_con_send(&session->s_con, msg);
2858 * Preemptively release a lease we expect to invalidate anyway.
2859 * Pass @inode always, @dentry is optional.
2861 void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
2862 struct dentry *dentry)
2864 struct ceph_dentry_info *di;
2865 struct ceph_mds_session *session;
2866 u32 seq;
2868 BUG_ON(inode == NULL);
2869 BUG_ON(dentry == NULL);
2871 /* is dentry lease valid? */
2872 spin_lock(&dentry->d_lock);
2873 di = ceph_dentry(dentry);
2874 if (!di || !di->lease_session ||
2875 di->lease_session->s_mds < 0 ||
2876 di->lease_gen != di->lease_session->s_cap_gen ||
2877 !time_before(jiffies, dentry->d_time)) {
2878 dout("lease_release inode %p dentry %p -- "
2879 "no lease\n",
2880 inode, dentry);
2881 spin_unlock(&dentry->d_lock);
2882 return;
2885 /* we do have a lease on this dentry; note mds and seq */
2886 session = ceph_get_mds_session(di->lease_session);
2887 seq = di->lease_seq;
2888 __ceph_mdsc_drop_dentry_lease(dentry);
2889 spin_unlock(&dentry->d_lock);
2891 dout("lease_release inode %p dentry %p to mds%d\n",
2892 inode, dentry, session->s_mds);
2893 ceph_mdsc_lease_send_msg(session, inode, dentry,
2894 CEPH_MDS_LEASE_RELEASE, seq);
2895 ceph_put_mds_session(session);
2899 * drop all leases (and dentry refs) in preparation for umount
2901 static void drop_leases(struct ceph_mds_client *mdsc)
2903 int i;
2905 dout("drop_leases\n");
2906 mutex_lock(&mdsc->mutex);
2907 for (i = 0; i < mdsc->max_sessions; i++) {
2908 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2909 if (!s)
2910 continue;
2911 mutex_unlock(&mdsc->mutex);
2912 mutex_lock(&s->s_mutex);
2913 mutex_unlock(&s->s_mutex);
2914 ceph_put_mds_session(s);
2915 mutex_lock(&mdsc->mutex);
2917 mutex_unlock(&mdsc->mutex);
2923 * delayed work -- periodically trim expired leases, renew caps with mds
2925 static void schedule_delayed(struct ceph_mds_client *mdsc)
2927 int delay = 5;
2928 unsigned hz = round_jiffies_relative(HZ * delay);
2929 schedule_delayed_work(&mdsc->delayed_work, hz);
2932 static void delayed_work(struct work_struct *work)
2934 int i;
2935 struct ceph_mds_client *mdsc =
2936 container_of(work, struct ceph_mds_client, delayed_work.work);
2937 int renew_interval;
2938 int renew_caps;
2940 dout("mdsc delayed_work\n");
2941 ceph_check_delayed_caps(mdsc);
2943 mutex_lock(&mdsc->mutex);
2944 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
2945 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
2946 mdsc->last_renew_caps);
2947 if (renew_caps)
2948 mdsc->last_renew_caps = jiffies;
2950 for (i = 0; i < mdsc->max_sessions; i++) {
2951 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2952 if (s == NULL)
2953 continue;
2954 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
2955 dout("resending session close request for mds%d\n",
2956 s->s_mds);
2957 request_close_session(mdsc, s);
2958 ceph_put_mds_session(s);
2959 continue;
2961 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
2962 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
2963 s->s_state = CEPH_MDS_SESSION_HUNG;
2964 pr_info("mds%d hung\n", s->s_mds);
2967 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
2968 /* this mds is failed or recovering, just wait */
2969 ceph_put_mds_session(s);
2970 continue;
2972 mutex_unlock(&mdsc->mutex);
2974 mutex_lock(&s->s_mutex);
2975 if (renew_caps)
2976 send_renew_caps(mdsc, s);
2977 else
2978 ceph_con_keepalive(&s->s_con);
2979 ceph_add_cap_releases(mdsc, s);
2980 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2981 s->s_state == CEPH_MDS_SESSION_HUNG)
2982 ceph_send_cap_releases(mdsc, s);
2983 mutex_unlock(&s->s_mutex);
2984 ceph_put_mds_session(s);
2986 mutex_lock(&mdsc->mutex);
2988 mutex_unlock(&mdsc->mutex);
2990 schedule_delayed(mdsc);
2993 int ceph_mdsc_init(struct ceph_fs_client *fsc)
2996 struct ceph_mds_client *mdsc;
2998 mdsc = kzalloc(sizeof(struct ceph_mds_client), GFP_NOFS);
2999 if (!mdsc)
3000 return -ENOMEM;
3001 mdsc->fsc = fsc;
3002 fsc->mdsc = mdsc;
3003 mutex_init(&mdsc->mutex);
3004 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
3005 if (mdsc->mdsmap == NULL)
3006 return -ENOMEM;
3008 init_completion(&mdsc->safe_umount_waiters);
3009 init_waitqueue_head(&mdsc->session_close_wq);
3010 INIT_LIST_HEAD(&mdsc->waiting_for_map);
3011 mdsc->sessions = NULL;
3012 mdsc->max_sessions = 0;
3013 mdsc->stopping = 0;
3014 init_rwsem(&mdsc->snap_rwsem);
3015 mdsc->snap_realms = RB_ROOT;
3016 INIT_LIST_HEAD(&mdsc->snap_empty);
3017 spin_lock_init(&mdsc->snap_empty_lock);
3018 mdsc->last_tid = 0;
3019 mdsc->request_tree = RB_ROOT;
3020 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
3021 mdsc->last_renew_caps = jiffies;
3022 INIT_LIST_HEAD(&mdsc->cap_delay_list);
3023 spin_lock_init(&mdsc->cap_delay_lock);
3024 INIT_LIST_HEAD(&mdsc->snap_flush_list);
3025 spin_lock_init(&mdsc->snap_flush_lock);
3026 mdsc->cap_flush_seq = 0;
3027 INIT_LIST_HEAD(&mdsc->cap_dirty);
3028 INIT_LIST_HEAD(&mdsc->cap_dirty_migrating);
3029 mdsc->num_cap_flushing = 0;
3030 spin_lock_init(&mdsc->cap_dirty_lock);
3031 init_waitqueue_head(&mdsc->cap_flushing_wq);
3032 spin_lock_init(&mdsc->dentry_lru_lock);
3033 INIT_LIST_HEAD(&mdsc->dentry_lru);
3035 ceph_caps_init(mdsc);
3036 ceph_adjust_min_caps(mdsc, fsc->min_caps);
3038 return 0;
3042 * Wait for safe replies on open mds requests. If we time out, drop
3043 * all requests from the tree to avoid dangling dentry refs.
3045 static void wait_requests(struct ceph_mds_client *mdsc)
3047 struct ceph_mds_request *req;
3048 struct ceph_fs_client *fsc = mdsc->fsc;
3050 mutex_lock(&mdsc->mutex);
3051 if (__get_oldest_req(mdsc)) {
3052 mutex_unlock(&mdsc->mutex);
3054 dout("wait_requests waiting for requests\n");
3055 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
3056 fsc->client->options->mount_timeout * HZ);
3058 /* tear down remaining requests */
3059 mutex_lock(&mdsc->mutex);
3060 while ((req = __get_oldest_req(mdsc))) {
3061 dout("wait_requests timed out on tid %llu\n",
3062 req->r_tid);
3063 __unregister_request(mdsc, req);
3066 mutex_unlock(&mdsc->mutex);
3067 dout("wait_requests done\n");
3071 * called before mount is ro, and before dentries are torn down.
3072 * (hmm, does this still race with new lookups?)
3074 void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
3076 dout("pre_umount\n");
3077 mdsc->stopping = 1;
3079 drop_leases(mdsc);
3080 ceph_flush_dirty_caps(mdsc);
3081 wait_requests(mdsc);
3084 * wait for reply handlers to drop their request refs and
3085 * their inode/dcache refs
3087 ceph_msgr_flush();
3091 * wait for all write mds requests to flush.
3093 static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
3095 struct ceph_mds_request *req = NULL, *nextreq;
3096 struct rb_node *n;
3098 mutex_lock(&mdsc->mutex);
3099 dout("wait_unsafe_requests want %lld\n", want_tid);
3100 restart:
3101 req = __get_oldest_req(mdsc);
3102 while (req && req->r_tid <= want_tid) {
3103 /* find next request */
3104 n = rb_next(&req->r_node);
3105 if (n)
3106 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
3107 else
3108 nextreq = NULL;
3109 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
3110 /* write op */
3111 ceph_mdsc_get_request(req);
3112 if (nextreq)
3113 ceph_mdsc_get_request(nextreq);
3114 mutex_unlock(&mdsc->mutex);
3115 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
3116 req->r_tid, want_tid);
3117 wait_for_completion(&req->r_safe_completion);
3118 mutex_lock(&mdsc->mutex);
3119 ceph_mdsc_put_request(req);
3120 if (!nextreq)
3121 break; /* next dne before, so we're done! */
3122 if (RB_EMPTY_NODE(&nextreq->r_node)) {
3123 /* next request was removed from tree */
3124 ceph_mdsc_put_request(nextreq);
3125 goto restart;
3127 ceph_mdsc_put_request(nextreq); /* won't go away */
3129 req = nextreq;
3131 mutex_unlock(&mdsc->mutex);
3132 dout("wait_unsafe_requests done\n");
3135 void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
3137 u64 want_tid, want_flush;
3139 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3140 return;
3142 dout("sync\n");
3143 mutex_lock(&mdsc->mutex);
3144 want_tid = mdsc->last_tid;
3145 want_flush = mdsc->cap_flush_seq;
3146 mutex_unlock(&mdsc->mutex);
3147 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
3149 ceph_flush_dirty_caps(mdsc);
3151 wait_unsafe_requests(mdsc, want_tid);
3152 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
3156 * true if all sessions are closed, or we force unmount
3158 static bool done_closing_sessions(struct ceph_mds_client *mdsc)
3160 int i, n = 0;
3162 if (mdsc->fsc->mount_state == CEPH_MOUNT_SHUTDOWN)
3163 return true;
3165 mutex_lock(&mdsc->mutex);
3166 for (i = 0; i < mdsc->max_sessions; i++)
3167 if (mdsc->sessions[i])
3168 n++;
3169 mutex_unlock(&mdsc->mutex);
3170 return n == 0;
3174 * called after sb is ro.
3176 void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
3178 struct ceph_mds_session *session;
3179 int i;
3180 struct ceph_fs_client *fsc = mdsc->fsc;
3181 unsigned long timeout = fsc->client->options->mount_timeout * HZ;
3183 dout("close_sessions\n");
3185 /* close sessions */
3186 mutex_lock(&mdsc->mutex);
3187 for (i = 0; i < mdsc->max_sessions; i++) {
3188 session = __ceph_lookup_mds_session(mdsc, i);
3189 if (!session)
3190 continue;
3191 mutex_unlock(&mdsc->mutex);
3192 mutex_lock(&session->s_mutex);
3193 __close_session(mdsc, session);
3194 mutex_unlock(&session->s_mutex);
3195 ceph_put_mds_session(session);
3196 mutex_lock(&mdsc->mutex);
3198 mutex_unlock(&mdsc->mutex);
3200 dout("waiting for sessions to close\n");
3201 wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc),
3202 timeout);
3204 /* tear down remaining sessions */
3205 mutex_lock(&mdsc->mutex);
3206 for (i = 0; i < mdsc->max_sessions; i++) {
3207 if (mdsc->sessions[i]) {
3208 session = get_session(mdsc->sessions[i]);
3209 __unregister_session(mdsc, session);
3210 mutex_unlock(&mdsc->mutex);
3211 mutex_lock(&session->s_mutex);
3212 remove_session_caps(session);
3213 mutex_unlock(&session->s_mutex);
3214 ceph_put_mds_session(session);
3215 mutex_lock(&mdsc->mutex);
3218 WARN_ON(!list_empty(&mdsc->cap_delay_list));
3219 mutex_unlock(&mdsc->mutex);
3221 ceph_cleanup_empty_realms(mdsc);
3223 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3225 dout("stopped\n");
3228 static void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
3230 dout("stop\n");
3231 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
3232 if (mdsc->mdsmap)
3233 ceph_mdsmap_destroy(mdsc->mdsmap);
3234 kfree(mdsc->sessions);
3235 ceph_caps_finalize(mdsc);
3238 void ceph_mdsc_destroy(struct ceph_fs_client *fsc)
3240 struct ceph_mds_client *mdsc = fsc->mdsc;
3242 dout("mdsc_destroy %p\n", mdsc);
3243 ceph_mdsc_stop(mdsc);
3245 /* flush out any connection work with references to us */
3246 ceph_msgr_flush();
3248 fsc->mdsc = NULL;
3249 kfree(mdsc);
3250 dout("mdsc_destroy %p done\n", mdsc);
3255 * handle mds map update.
3257 void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
3259 u32 epoch;
3260 u32 maplen;
3261 void *p = msg->front.iov_base;
3262 void *end = p + msg->front.iov_len;
3263 struct ceph_mdsmap *newmap, *oldmap;
3264 struct ceph_fsid fsid;
3265 int err = -EINVAL;
3267 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
3268 ceph_decode_copy(&p, &fsid, sizeof(fsid));
3269 if (ceph_check_fsid(mdsc->fsc->client, &fsid) < 0)
3270 return;
3271 epoch = ceph_decode_32(&p);
3272 maplen = ceph_decode_32(&p);
3273 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
3275 /* do we need it? */
3276 ceph_monc_got_mdsmap(&mdsc->fsc->client->monc, epoch);
3277 mutex_lock(&mdsc->mutex);
3278 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
3279 dout("handle_map epoch %u <= our %u\n",
3280 epoch, mdsc->mdsmap->m_epoch);
3281 mutex_unlock(&mdsc->mutex);
3282 return;
3285 newmap = ceph_mdsmap_decode(&p, end);
3286 if (IS_ERR(newmap)) {
3287 err = PTR_ERR(newmap);
3288 goto bad_unlock;
3291 /* swap into place */
3292 if (mdsc->mdsmap) {
3293 oldmap = mdsc->mdsmap;
3294 mdsc->mdsmap = newmap;
3295 check_new_map(mdsc, newmap, oldmap);
3296 ceph_mdsmap_destroy(oldmap);
3297 } else {
3298 mdsc->mdsmap = newmap; /* first mds map */
3300 mdsc->fsc->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
3302 __wake_requests(mdsc, &mdsc->waiting_for_map);
3304 mutex_unlock(&mdsc->mutex);
3305 schedule_delayed(mdsc);
3306 return;
3308 bad_unlock:
3309 mutex_unlock(&mdsc->mutex);
3310 bad:
3311 pr_err("error decoding mdsmap %d\n", err);
3312 return;
3315 static struct ceph_connection *con_get(struct ceph_connection *con)
3317 struct ceph_mds_session *s = con->private;
3319 if (get_session(s)) {
3320 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
3321 return con;
3323 dout("mdsc con_get %p FAIL\n", s);
3324 return NULL;
3327 static void con_put(struct ceph_connection *con)
3329 struct ceph_mds_session *s = con->private;
3331 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref) - 1);
3332 ceph_put_mds_session(s);
3336 * if the client is unresponsive for long enough, the mds will kill
3337 * the session entirely.
3339 static void peer_reset(struct ceph_connection *con)
3341 struct ceph_mds_session *s = con->private;
3342 struct ceph_mds_client *mdsc = s->s_mdsc;
3344 pr_warning("mds%d closed our session\n", s->s_mds);
3345 send_mds_reconnect(mdsc, s);
3348 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
3350 struct ceph_mds_session *s = con->private;
3351 struct ceph_mds_client *mdsc = s->s_mdsc;
3352 int type = le16_to_cpu(msg->hdr.type);
3354 mutex_lock(&mdsc->mutex);
3355 if (__verify_registered_session(mdsc, s) < 0) {
3356 mutex_unlock(&mdsc->mutex);
3357 goto out;
3359 mutex_unlock(&mdsc->mutex);
3361 switch (type) {
3362 case CEPH_MSG_MDS_MAP:
3363 ceph_mdsc_handle_map(mdsc, msg);
3364 break;
3365 case CEPH_MSG_CLIENT_SESSION:
3366 handle_session(s, msg);
3367 break;
3368 case CEPH_MSG_CLIENT_REPLY:
3369 handle_reply(s, msg);
3370 break;
3371 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
3372 handle_forward(mdsc, s, msg);
3373 break;
3374 case CEPH_MSG_CLIENT_CAPS:
3375 ceph_handle_caps(s, msg);
3376 break;
3377 case CEPH_MSG_CLIENT_SNAP:
3378 ceph_handle_snap(mdsc, s, msg);
3379 break;
3380 case CEPH_MSG_CLIENT_LEASE:
3381 handle_lease(mdsc, s, msg);
3382 break;
3384 default:
3385 pr_err("received unknown message type %d %s\n", type,
3386 ceph_msg_type_name(type));
3388 out:
3389 ceph_msg_put(msg);
3393 * authentication
3395 static int get_authorizer(struct ceph_connection *con,
3396 void **buf, int *len, int *proto,
3397 void **reply_buf, int *reply_len, int force_new)
3399 struct ceph_mds_session *s = con->private;
3400 struct ceph_mds_client *mdsc = s->s_mdsc;
3401 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3402 int ret = 0;
3404 if (force_new && s->s_authorizer) {
3405 ac->ops->destroy_authorizer(ac, s->s_authorizer);
3406 s->s_authorizer = NULL;
3408 if (s->s_authorizer == NULL) {
3409 if (ac->ops->create_authorizer) {
3410 ret = ac->ops->create_authorizer(
3411 ac, CEPH_ENTITY_TYPE_MDS,
3412 &s->s_authorizer,
3413 &s->s_authorizer_buf,
3414 &s->s_authorizer_buf_len,
3415 &s->s_authorizer_reply_buf,
3416 &s->s_authorizer_reply_buf_len);
3417 if (ret)
3418 return ret;
3422 *proto = ac->protocol;
3423 *buf = s->s_authorizer_buf;
3424 *len = s->s_authorizer_buf_len;
3425 *reply_buf = s->s_authorizer_reply_buf;
3426 *reply_len = s->s_authorizer_reply_buf_len;
3427 return 0;
3431 static int verify_authorizer_reply(struct ceph_connection *con, int len)
3433 struct ceph_mds_session *s = con->private;
3434 struct ceph_mds_client *mdsc = s->s_mdsc;
3435 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3437 return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
3440 static int invalidate_authorizer(struct ceph_connection *con)
3442 struct ceph_mds_session *s = con->private;
3443 struct ceph_mds_client *mdsc = s->s_mdsc;
3444 struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
3446 if (ac->ops->invalidate_authorizer)
3447 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3449 return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
3452 static const struct ceph_connection_operations mds_con_ops = {
3453 .get = con_get,
3454 .put = con_put,
3455 .dispatch = dispatch,
3456 .get_authorizer = get_authorizer,
3457 .verify_authorizer_reply = verify_authorizer_reply,
3458 .invalidate_authorizer = invalidate_authorizer,
3459 .peer_reset = peer_reset,
3462 /* eof */