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ceph: wait for mds OPEN reply to indicate reconnect success
[deliverable/linux.git] / fs / ceph / mds_client.c
CommitLineData
2f2dc053
SW		 1#include "ceph_debug.h"
2
3#include <linux/wait.h>
5a0e3ad6 4#include <linux/slab.h>
2f2dc053
SW		 5#include <linux/sched.h>
6
7#include "mds_client.h"
8#include "mon_client.h"
9#include "super.h"
10#include "messenger.h"
11#include "decode.h"
4e7a5dcd 12#include "auth.h"
93cea5be 13#include "pagelist.h"
2f2dc053
SW		 14
15/*
16 * A cluster of MDS (metadata server) daemons is responsible for
17 * managing the file system namespace (the directory hierarchy and
18 * inodes) and for coordinating shared access to storage. Metadata is
19 * partitioning hierarchically across a number of servers, and that
20 * partition varies over time as the cluster adjusts the distribution
21 * in order to balance load.
22 *
23 * The MDS client is primarily responsible to managing synchronous
24 * metadata requests for operations like open, unlink, and so forth.
25 * If there is a MDS failure, we find out about it when we (possibly
26 * request and) receive a new MDS map, and can resubmit affected
27 * requests.
28 *
29 * For the most part, though, we take advantage of a lossless
30 * communications channel to the MDS, and do not need to worry about
31 * timing out or resubmitting requests.
32 *
33 * We maintain a stateful "session" with each MDS we interact with.
34 * Within each session, we sent periodic heartbeat messages to ensure
35 * any capabilities or leases we have been issues remain valid. If
36 * the session times out and goes stale, our leases and capabilities
37 * are no longer valid.
38 */
39
40static void __wake_requests(struct ceph_mds_client *mdsc,
41 struct list_head *head);
42
43const static struct ceph_connection_operations mds_con_ops;
44
45
46/*
47 * mds reply parsing
48 */
49
50/*
51 * parse individual inode info
52 */
53static int parse_reply_info_in(void **p, void *end,
54 struct ceph_mds_reply_info_in *info)
55{
56 int err = -EIO;
57
58 info->in = *p;
59 *p += sizeof(struct ceph_mds_reply_inode) +
60 sizeof(*info->in->fragtree.splits) *
61 le32_to_cpu(info->in->fragtree.nsplits);
62
63 ceph_decode_32_safe(p, end, info->symlink_len, bad);
64 ceph_decode_need(p, end, info->symlink_len, bad);
65 info->symlink = *p;
66 *p += info->symlink_len;
67
68 ceph_decode_32_safe(p, end, info->xattr_len, bad);
69 ceph_decode_need(p, end, info->xattr_len, bad);
70 info->xattr_data = *p;
71 *p += info->xattr_len;
72 return 0;
73bad:
74 return err;
75}
76
77/*
78 * parse a normal reply, which may contain a (dir+)dentry and/or a
79 * target inode.
80 */
81static int parse_reply_info_trace(void **p, void *end,
82 struct ceph_mds_reply_info_parsed *info)
83{
84 int err;
85
86 if (info->head->is_dentry) {
87 err = parse_reply_info_in(p, end, &info->diri);
88 if (err < 0)
89 goto out_bad;
90
91 if (unlikely(*p + sizeof(*info->dirfrag) > end))
92 goto bad;
93 info->dirfrag = *p;
94 *p += sizeof(*info->dirfrag) +
95 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
96 if (unlikely(*p > end))
97 goto bad;
98
99 ceph_decode_32_safe(p, end, info->dname_len, bad);
100 ceph_decode_need(p, end, info->dname_len, bad);
101 info->dname = *p;
102 *p += info->dname_len;
103 info->dlease = *p;
104 *p += sizeof(*info->dlease);
105 }
106
107 if (info->head->is_target) {
108 err = parse_reply_info_in(p, end, &info->targeti);
109 if (err < 0)
110 goto out_bad;
111 }
112
113 if (unlikely(*p != end))
114 goto bad;
115 return 0;
116
117bad:
118 err = -EIO;
119out_bad:
120 pr_err("problem parsing mds trace %d\n", err);
121 return err;
122}
123
124/*
125 * parse readdir results
126 */
127static int parse_reply_info_dir(void **p, void *end,
128 struct ceph_mds_reply_info_parsed *info)
129{
130 u32 num, i = 0;
131 int err;
132
133 info->dir_dir = *p;
134 if (*p + sizeof(*info->dir_dir) > end)
135 goto bad;
136 *p += sizeof(*info->dir_dir) +
137 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
138 if (*p > end)
139 goto bad;
140
141 ceph_decode_need(p, end, sizeof(num) + 2, bad);
c89136ea
SW		 142 num = ceph_decode_32(p);
143 info->dir_end = ceph_decode_8(p);
144 info->dir_complete = ceph_decode_8(p);
2f2dc053
SW		 145 if (num == 0)
146 goto done;
147
148 /* alloc large array */
149 info->dir_nr = num;
150 info->dir_in = kcalloc(num, sizeof(*info->dir_in) +
151 sizeof(*info->dir_dname) +
152 sizeof(*info->dir_dname_len) +
153 sizeof(*info->dir_dlease),
154 GFP_NOFS);
155 if (info->dir_in == NULL) {
156 err = -ENOMEM;
157 goto out_bad;
158 }
159 info->dir_dname = (void *)(info->dir_in + num);
160 info->dir_dname_len = (void *)(info->dir_dname + num);
161 info->dir_dlease = (void *)(info->dir_dname_len + num);
162
163 while (num) {
164 /* dentry */
165 ceph_decode_need(p, end, sizeof(u32)*2, bad);
c89136ea 166 info->dir_dname_len[i] = ceph_decode_32(p);
2f2dc053
SW		 167 ceph_decode_need(p, end, info->dir_dname_len[i], bad);
168 info->dir_dname[i] = *p;
169 *p += info->dir_dname_len[i];
170 dout("parsed dir dname '%.*s'\n", info->dir_dname_len[i],
171 info->dir_dname[i]);
172 info->dir_dlease[i] = *p;
173 *p += sizeof(struct ceph_mds_reply_lease);
174
175 /* inode */
176 err = parse_reply_info_in(p, end, &info->dir_in[i]);
177 if (err < 0)
178 goto out_bad;
179 i++;
180 num--;
181 }
182
183done:
184 if (*p != end)
185 goto bad;
186 return 0;
187
188bad:
189 err = -EIO;
190out_bad:
191 pr_err("problem parsing dir contents %d\n", err);
192 return err;
193}
194
195/*
196 * parse entire mds reply
197 */
198static int parse_reply_info(struct ceph_msg *msg,
199 struct ceph_mds_reply_info_parsed *info)
200{
201 void *p, *end;
202 u32 len;
203 int err;
204
205 info->head = msg->front.iov_base;
206 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
207 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
208
209 /* trace */
210 ceph_decode_32_safe(&p, end, len, bad);
211 if (len > 0) {
212 err = parse_reply_info_trace(&p, p+len, info);
213 if (err < 0)
214 goto out_bad;
215 }
216
217 /* dir content */
218 ceph_decode_32_safe(&p, end, len, bad);
219 if (len > 0) {
220 err = parse_reply_info_dir(&p, p+len, info);
221 if (err < 0)
222 goto out_bad;
223 }
224
225 /* snap blob */
226 ceph_decode_32_safe(&p, end, len, bad);
227 info->snapblob_len = len;
228 info->snapblob = p;
229 p += len;
230
231 if (p != end)
232 goto bad;
233 return 0;
234
235bad:
236 err = -EIO;
237out_bad:
238 pr_err("mds parse_reply err %d\n", err);
239 return err;
240}
241
242static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
243{
244 kfree(info->dir_in);
245}
246
247
248/*
249 * sessions
250 */
251static const char *session_state_name(int s)
252{
253 switch (s) {
254 case CEPH_MDS_SESSION_NEW: return "new";
255 case CEPH_MDS_SESSION_OPENING: return "opening";
256 case CEPH_MDS_SESSION_OPEN: return "open";
257 case CEPH_MDS_SESSION_HUNG: return "hung";
258 case CEPH_MDS_SESSION_CLOSING: return "closing";
44ca18f2 259 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
2f2dc053
SW		 260 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
261 default: return "???";
262 }
263}
264
265static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
266{
267 if (atomic_inc_not_zero(&s->s_ref)) {
268 dout("mdsc get_session %p %d -> %d\n", s,
269 atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
270 return s;
271 } else {
272 dout("mdsc get_session %p 0 -- FAIL", s);
273 return NULL;
274 }
275}
276
277void ceph_put_mds_session(struct ceph_mds_session *s)
278{
279 dout("mdsc put_session %p %d -> %d\n", s,
280 atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
4e7a5dcd
SW		 281 if (atomic_dec_and_test(&s->s_ref)) {
282 if (s->s_authorizer)
283 s->s_mdsc->client->monc.auth->ops->destroy_authorizer(
284 s->s_mdsc->client->monc.auth, s->s_authorizer);
2f2dc053 285 kfree(s);
4e7a5dcd 286 }
2f2dc053
SW		 287}
288
289/*
290 * called under mdsc->mutex
291 */
292struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
293 int mds)
294{
295 struct ceph_mds_session *session;
296
297 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
298 return NULL;
299 session = mdsc->sessions[mds];
300 dout("lookup_mds_session %p %d\n", session,
301 atomic_read(&session->s_ref));
302 get_session(session);
303 return session;
304}
305
306static bool __have_session(struct ceph_mds_client *mdsc, int mds)
307{
308 if (mds >= mdsc->max_sessions)
309 return false;
310 return mdsc->sessions[mds];
311}
312
2600d2dd
SW		 313static int __verify_registered_session(struct ceph_mds_client *mdsc,
314 struct ceph_mds_session *s)
315{
316 if (s->s_mds >= mdsc->max_sessions ||
317 mdsc->sessions[s->s_mds] != s)
318 return -ENOENT;
319 return 0;
320}
321
2f2dc053
SW		 322/*
323 * create+register a new session for given mds.
324 * called under mdsc->mutex.
325 */
326static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
327 int mds)
328{
329 struct ceph_mds_session *s;
330
331 s = kzalloc(sizeof(*s), GFP_NOFS);
4736b009
DC		 332 if (!s)
333 return ERR_PTR(-ENOMEM);
2f2dc053
SW		 334 s->s_mdsc = mdsc;
335 s->s_mds = mds;
336 s->s_state = CEPH_MDS_SESSION_NEW;
337 s->s_ttl = 0;
338 s->s_seq = 0;
339 mutex_init(&s->s_mutex);
340
341 ceph_con_init(mdsc->client->msgr, &s->s_con);
342 s->s_con.private = s;
343 s->s_con.ops = &mds_con_ops;
344 s->s_con.peer_name.type = CEPH_ENTITY_TYPE_MDS;
345 s->s_con.peer_name.num = cpu_to_le64(mds);
2f2dc053
SW		 346
347 spin_lock_init(&s->s_cap_lock);
348 s->s_cap_gen = 0;
349 s->s_cap_ttl = 0;
350 s->s_renew_requested = 0;
351 s->s_renew_seq = 0;
352 INIT_LIST_HEAD(&s->s_caps);
353 s->s_nr_caps = 0;
5dacf091 354 s->s_trim_caps = 0;
2f2dc053
SW		 355 atomic_set(&s->s_ref, 1);
356 INIT_LIST_HEAD(&s->s_waiting);
357 INIT_LIST_HEAD(&s->s_unsafe);
358 s->s_num_cap_releases = 0;
7c1332b8 359 s->s_cap_iterator = NULL;
2f2dc053
SW		 360 INIT_LIST_HEAD(&s->s_cap_releases);
361 INIT_LIST_HEAD(&s->s_cap_releases_done);
362 INIT_LIST_HEAD(&s->s_cap_flushing);
363 INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
364
365 dout("register_session mds%d\n", mds);
366 if (mds >= mdsc->max_sessions) {
367 int newmax = 1 << get_count_order(mds+1);
368 struct ceph_mds_session **sa;
369
370 dout("register_session realloc to %d\n", newmax);
371 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
372 if (sa == NULL)
42ce56e5 373 goto fail_realloc;
2f2dc053
SW		 374 if (mdsc->sessions) {
375 memcpy(sa, mdsc->sessions,
376 mdsc->max_sessions * sizeof(void *));
377 kfree(mdsc->sessions);
378 }
379 mdsc->sessions = sa;
380 mdsc->max_sessions = newmax;
381 }
382 mdsc->sessions[mds] = s;
383 atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
42ce56e5
SW		 384
385 ceph_con_open(&s->s_con, ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
386
2f2dc053 387 return s;
42ce56e5
SW		 388
389fail_realloc:
390 kfree(s);
391 return ERR_PTR(-ENOMEM);
2f2dc053
SW		 392}
393
394/*
395 * called under mdsc->mutex
396 */
2600d2dd 397static void __unregister_session(struct ceph_mds_client *mdsc,
42ce56e5 398 struct ceph_mds_session *s)
2f2dc053 399{
2600d2dd
SW		 400 dout("__unregister_session mds%d %p\n", s->s_mds, s);
401 BUG_ON(mdsc->sessions[s->s_mds] != s);
42ce56e5
SW		 402 mdsc->sessions[s->s_mds] = NULL;
403 ceph_con_close(&s->s_con);
404 ceph_put_mds_session(s);
2f2dc053
SW		 405}
406
407/*
408 * drop session refs in request.
409 *
410 * should be last request ref, or hold mdsc->mutex
411 */
412static void put_request_session(struct ceph_mds_request *req)
413{
414 if (req->r_session) {
415 ceph_put_mds_session(req->r_session);
416 req->r_session = NULL;
417 }
418}
419
153c8e6b 420void ceph_mdsc_release_request(struct kref *kref)
2f2dc053 421{
153c8e6b
SW		 422 struct ceph_mds_request *req = container_of(kref,
423 struct ceph_mds_request,
424 r_kref);
425 if (req->r_request)
426 ceph_msg_put(req->r_request);
427 if (req->r_reply) {
428 ceph_msg_put(req->r_reply);
429 destroy_reply_info(&req->r_reply_info);
430 }
431 if (req->r_inode) {
432 ceph_put_cap_refs(ceph_inode(req->r_inode),
433 CEPH_CAP_PIN);
434 iput(req->r_inode);
435 }
436 if (req->r_locked_dir)
437 ceph_put_cap_refs(ceph_inode(req->r_locked_dir),
438 CEPH_CAP_PIN);
439 if (req->r_target_inode)
440 iput(req->r_target_inode);
441 if (req->r_dentry)
442 dput(req->r_dentry);
443 if (req->r_old_dentry) {
444 ceph_put_cap_refs(
445 ceph_inode(req->r_old_dentry->d_parent->d_inode),
446 CEPH_CAP_PIN);
447 dput(req->r_old_dentry);
2f2dc053 448 }
153c8e6b
SW		 449 kfree(req->r_path1);
450 kfree(req->r_path2);
451 put_request_session(req);
452 ceph_unreserve_caps(&req->r_caps_reservation);
453 kfree(req);
2f2dc053
SW		 454}
455
456/*
457 * lookup session, bump ref if found.
458 *
459 * called under mdsc->mutex.
460 */
461static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
462 u64 tid)
463{
464 struct ceph_mds_request *req;
44ca18f2
SW		 465 struct rb_node *n = mdsc->request_tree.rb_node;
466
467 while (n) {
468 req = rb_entry(n, struct ceph_mds_request, r_node);
469 if (tid < req->r_tid)
470 n = n->rb_left;
471 else if (tid > req->r_tid)
472 n = n->rb_right;
473 else {
474 ceph_mdsc_get_request(req);
475 return req;
476 }
477 }
478 return NULL;
479}
480
481static void __insert_request(struct ceph_mds_client *mdsc,
482 struct ceph_mds_request *new)
483{
484 struct rb_node **p = &mdsc->request_tree.rb_node;
485 struct rb_node *parent = NULL;
486 struct ceph_mds_request *req = NULL;
487
488 while (*p) {
489 parent = *p;
490 req = rb_entry(parent, struct ceph_mds_request, r_node);
491 if (new->r_tid < req->r_tid)
492 p = &(*p)->rb_left;
493 else if (new->r_tid > req->r_tid)
494 p = &(*p)->rb_right;
495 else
496 BUG();
497 }
498
499 rb_link_node(&new->r_node, parent, p);
500 rb_insert_color(&new->r_node, &mdsc->request_tree);
2f2dc053
SW		 501}
502
503/*
504 * Register an in-flight request, and assign a tid. Link to directory
505 * are modifying (if any).
506 *
507 * Called under mdsc->mutex.
508 */
509static void __register_request(struct ceph_mds_client *mdsc,
510 struct ceph_mds_request *req,
511 struct inode *dir)
512{
513 req->r_tid = ++mdsc->last_tid;
514 if (req->r_num_caps)
515 ceph_reserve_caps(&req->r_caps_reservation, req->r_num_caps);
516 dout("__register_request %p tid %lld\n", req, req->r_tid);
517 ceph_mdsc_get_request(req);
44ca18f2 518 __insert_request(mdsc, req);
2f2dc053
SW		 519
520 if (dir) {
521 struct ceph_inode_info *ci = ceph_inode(dir);
522
523 spin_lock(&ci->i_unsafe_lock);
524 req->r_unsafe_dir = dir;
525 list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
526 spin_unlock(&ci->i_unsafe_lock);
527 }
528}
529
530static void __unregister_request(struct ceph_mds_client *mdsc,
531 struct ceph_mds_request *req)
532{
533 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
44ca18f2 534 rb_erase(&req->r_node, &mdsc->request_tree);
80fc7314 535 RB_CLEAR_NODE(&req->r_node);
2f2dc053
SW		 536
537 if (req->r_unsafe_dir) {
538 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
539
540 spin_lock(&ci->i_unsafe_lock);
541 list_del_init(&req->r_unsafe_dir_item);
542 spin_unlock(&ci->i_unsafe_lock);
543 }
94aa8ae1
SW		 544
545 ceph_mdsc_put_request(req);
2f2dc053
SW		 546}
547
548/*
549 * Choose mds to send request to next. If there is a hint set in the
550 * request (e.g., due to a prior forward hint from the mds), use that.
551 * Otherwise, consult frag tree and/or caps to identify the
552 * appropriate mds. If all else fails, choose randomly.
553 *
554 * Called under mdsc->mutex.
555 */
556static int __choose_mds(struct ceph_mds_client *mdsc,
557 struct ceph_mds_request *req)
558{
559 struct inode *inode;
560 struct ceph_inode_info *ci;
561 struct ceph_cap *cap;
562 int mode = req->r_direct_mode;
563 int mds = -1;
564 u32 hash = req->r_direct_hash;
565 bool is_hash = req->r_direct_is_hash;
566
567 /*
568 * is there a specific mds we should try? ignore hint if we have
569 * no session and the mds is not up (active or recovering).
570 */
571 if (req->r_resend_mds >= 0 &&
572 (__have_session(mdsc, req->r_resend_mds) ||
573 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
574 dout("choose_mds using resend_mds mds%d\n",
575 req->r_resend_mds);
576 return req->r_resend_mds;
577 }
578
579 if (mode == USE_RANDOM_MDS)
580 goto random;
581
582 inode = NULL;
583 if (req->r_inode) {
584 inode = req->r_inode;
585 } else if (req->r_dentry) {
586 if (req->r_dentry->d_inode) {
587 inode = req->r_dentry->d_inode;
588 } else {
589 inode = req->r_dentry->d_parent->d_inode;
590 hash = req->r_dentry->d_name.hash;
591 is_hash = true;
592 }
593 }
594 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
595 (int)hash, mode);
596 if (!inode)
597 goto random;
598 ci = ceph_inode(inode);
599
600 if (is_hash && S_ISDIR(inode->i_mode)) {
601 struct ceph_inode_frag frag;
602 int found;
603
604 ceph_choose_frag(ci, hash, &frag, &found);
605 if (found) {
606 if (mode == USE_ANY_MDS && frag.ndist > 0) {
607 u8 r;
608
609 /* choose a random replica */
610 get_random_bytes(&r, 1);
611 r %= frag.ndist;
612 mds = frag.dist[r];
613 dout("choose_mds %p %llx.%llx "
614 "frag %u mds%d (%d/%d)\n",
615 inode, ceph_vinop(inode),
616 frag.frag, frag.mds,
617 (int)r, frag.ndist);
618 return mds;
619 }
620
621 /* since this file/dir wasn't known to be
622 * replicated, then we want to look for the
623 * authoritative mds. */
624 mode = USE_AUTH_MDS;
625 if (frag.mds >= 0) {
626 /* choose auth mds */
627 mds = frag.mds;
628 dout("choose_mds %p %llx.%llx "
629 "frag %u mds%d (auth)\n",
630 inode, ceph_vinop(inode), frag.frag, mds);
631 return mds;
632 }
633 }
634 }
635
636 spin_lock(&inode->i_lock);
637 cap = NULL;
638 if (mode == USE_AUTH_MDS)
639 cap = ci->i_auth_cap;
640 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
641 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
642 if (!cap) {
643 spin_unlock(&inode->i_lock);
644 goto random;
645 }
646 mds = cap->session->s_mds;
647 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
648 inode, ceph_vinop(inode), mds,
649 cap == ci->i_auth_cap ? "auth " : "", cap);
650 spin_unlock(&inode->i_lock);
651 return mds;
652
653random:
654 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
655 dout("choose_mds chose random mds%d\n", mds);
656 return mds;
657}
658
659
660/*
661 * session messages
662 */
663static struct ceph_msg *create_session_msg(u32 op, u64 seq)
664{
665 struct ceph_msg *msg;
666 struct ceph_mds_session_head *h;
667
bb257664 668 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h));
a79832f2 669 if (!msg) {
2f2dc053 670 pr_err("create_session_msg ENOMEM creating msg\n");
a79832f2 671 return NULL;
2f2dc053
SW		 672 }
673 h = msg->front.iov_base;
674 h->op = cpu_to_le32(op);
675 h->seq = cpu_to_le64(seq);
676 return msg;
677}
678
679/*
680 * send session open request.
681 *
682 * called under mdsc->mutex
683 */
684static int __open_session(struct ceph_mds_client *mdsc,
685 struct ceph_mds_session *session)
686{
687 struct ceph_msg *msg;
688 int mstate;
689 int mds = session->s_mds;
2f2dc053
SW		 690
691 /* wait for mds to go active? */
692 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
693 dout("open_session to mds%d (%s)\n", mds,
694 ceph_mds_state_name(mstate));
695 session->s_state = CEPH_MDS_SESSION_OPENING;
696 session->s_renew_requested = jiffies;
697
698 /* send connect message */
699 msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
a79832f2
SW		 700 if (!msg)
701 return -ENOMEM;
2f2dc053 702 ceph_con_send(&session->s_con, msg);
2f2dc053
SW		 703 return 0;
704}
705
706/*
707 * session caps
708 */
709
710/*
711 * Free preallocated cap messages assigned to this session
712 */
713static void cleanup_cap_releases(struct ceph_mds_session *session)
714{
715 struct ceph_msg *msg;
716
717 spin_lock(&session->s_cap_lock);
718 while (!list_empty(&session->s_cap_releases)) {
719 msg = list_first_entry(&session->s_cap_releases,
720 struct ceph_msg, list_head);
721 list_del_init(&msg->list_head);
722 ceph_msg_put(msg);
723 }
724 while (!list_empty(&session->s_cap_releases_done)) {
725 msg = list_first_entry(&session->s_cap_releases_done,
726 struct ceph_msg, list_head);
727 list_del_init(&msg->list_head);
728 ceph_msg_put(msg);
729 }
730 spin_unlock(&session->s_cap_lock);
731}
732
733/*
f818a736
SW		 734 * Helper to safely iterate over all caps associated with a session, with
735 * special care taken to handle a racing __ceph_remove_cap().
2f2dc053 736 *
f818a736 737 * Caller must hold session s_mutex.
2f2dc053
SW		 738 */
739static int iterate_session_caps(struct ceph_mds_session *session,
740 int (*cb)(struct inode *, struct ceph_cap *,
741 void *), void *arg)
742{
7c1332b8
SW		 743 struct list_head *p;
744 struct ceph_cap *cap;
745 struct inode *inode, *last_inode = NULL;
746 struct ceph_cap *old_cap = NULL;
2f2dc053
SW		 747 int ret;
748
749 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
750 spin_lock(&session->s_cap_lock);
7c1332b8
SW		 751 p = session->s_caps.next;
752 while (p != &session->s_caps) {
753 cap = list_entry(p, struct ceph_cap, session_caps);
2f2dc053 754 inode = igrab(&cap->ci->vfs_inode);
7c1332b8
SW		 755 if (!inode) {
756 p = p->next;
2f2dc053 757 continue;
7c1332b8
SW		 758 }
759 session->s_cap_iterator = cap;
2f2dc053 760 spin_unlock(&session->s_cap_lock);
7c1332b8
SW		 761
762 if (last_inode) {
763 iput(last_inode);
764 last_inode = NULL;
765 }
766 if (old_cap) {
767 ceph_put_cap(old_cap);
768 old_cap = NULL;
769 }
770
2f2dc053 771 ret = cb(inode, cap, arg);
7c1332b8
SW		 772 last_inode = inode;
773
2f2dc053 774 spin_lock(&session->s_cap_lock);
7c1332b8
SW		 775 p = p->next;
776 if (cap->ci == NULL) {
777 dout("iterate_session_caps finishing cap %p removal\n",
778 cap);
779 BUG_ON(cap->session != session);
780 list_del_init(&cap->session_caps);
781 session->s_nr_caps--;
782 cap->session = NULL;
783 old_cap = cap; /* put_cap it w/o locks held */
784 }
5dacf091
SW		 785 if (ret < 0)
786 goto out;
2f2dc053 787 }
5dacf091
SW		 788 ret = 0;
789out:
7c1332b8 790 session->s_cap_iterator = NULL;
2f2dc053 791 spin_unlock(&session->s_cap_lock);
7c1332b8
SW		 792
793 if (last_inode)
794 iput(last_inode);
795 if (old_cap)
796 ceph_put_cap(old_cap);
797
5dacf091 798 return ret;
2f2dc053
SW		 799}
800
801static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
802 void *arg)
803{
804 struct ceph_inode_info *ci = ceph_inode(inode);
805 dout("removing cap %p, ci is %p, inode is %p\n",
806 cap, ci, &ci->vfs_inode);
807 ceph_remove_cap(cap);
808 return 0;
809}
810
811/*
812 * caller must hold session s_mutex
813 */
814static void remove_session_caps(struct ceph_mds_session *session)
815{
816 dout("remove_session_caps on %p\n", session);
817 iterate_session_caps(session, remove_session_caps_cb, NULL);
818 BUG_ON(session->s_nr_caps > 0);
819 cleanup_cap_releases(session);
820}
821
822/*
823 * wake up any threads waiting on this session's caps. if the cap is
824 * old (didn't get renewed on the client reconnect), remove it now.
825 *
826 * caller must hold s_mutex.
827 */
828static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
829 void *arg)
830{
0dc2570f
SW		 831 struct ceph_inode_info *ci = ceph_inode(inode);
832
833 wake_up(&ci->i_cap_wq);
834 if (arg) {
835 spin_lock(&inode->i_lock);
836 ci->i_wanted_max_size = 0;
837 ci->i_requested_max_size = 0;
838 spin_unlock(&inode->i_lock);
839 }
2f2dc053
SW		 840 return 0;
841}
842
0dc2570f
SW		 843static void wake_up_session_caps(struct ceph_mds_session *session,
844 int reconnect)
2f2dc053
SW		 845{
846 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
0dc2570f
SW		 847 iterate_session_caps(session, wake_up_session_cb,
848 (void *)(unsigned long)reconnect);
2f2dc053
SW		 849}
850
851/*
852 * Send periodic message to MDS renewing all currently held caps. The
853 * ack will reset the expiration for all caps from this session.
854 *
855 * caller holds s_mutex
856 */
857static int send_renew_caps(struct ceph_mds_client *mdsc,
858 struct ceph_mds_session *session)
859{
860 struct ceph_msg *msg;
861 int state;
862
863 if (time_after_eq(jiffies, session->s_cap_ttl) &&
864 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
865 pr_info("mds%d caps stale\n", session->s_mds);
e4cb4cb8 866 session->s_renew_requested = jiffies;
2f2dc053
SW		 867
868 /* do not try to renew caps until a recovering mds has reconnected
869 * with its clients. */
870 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
871 if (state < CEPH_MDS_STATE_RECONNECT) {
872 dout("send_renew_caps ignoring mds%d (%s)\n",
873 session->s_mds, ceph_mds_state_name(state));
874 return 0;
875 }
876
877 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
878 ceph_mds_state_name(state));
2f2dc053
SW		 879 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
880 ++session->s_renew_seq);
a79832f2
SW		 881 if (!msg)
882 return -ENOMEM;
2f2dc053
SW		 883 ceph_con_send(&session->s_con, msg);
884 return 0;
885}
886
887/*
888 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
0dc2570f
SW		 889 *
890 * Called under session->s_mutex
2f2dc053
SW		 891 */
892static void renewed_caps(struct ceph_mds_client *mdsc,
893 struct ceph_mds_session *session, int is_renew)
894{
895 int was_stale;
896 int wake = 0;
897
898 spin_lock(&session->s_cap_lock);
899 was_stale = is_renew && (session->s_cap_ttl == 0 ||
900 time_after_eq(jiffies, session->s_cap_ttl));
901
902 session->s_cap_ttl = session->s_renew_requested +
903 mdsc->mdsmap->m_session_timeout*HZ;
904
905 if (was_stale) {
906 if (time_before(jiffies, session->s_cap_ttl)) {
907 pr_info("mds%d caps renewed\n", session->s_mds);
908 wake = 1;
909 } else {
910 pr_info("mds%d caps still stale\n", session->s_mds);
911 }
912 }
913 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
914 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
915 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
916 spin_unlock(&session->s_cap_lock);
917
918 if (wake)
0dc2570f 919 wake_up_session_caps(session, 0);
2f2dc053
SW		 920}
921
922/*
923 * send a session close request
924 */
925static int request_close_session(struct ceph_mds_client *mdsc,
926 struct ceph_mds_session *session)
927{
928 struct ceph_msg *msg;
2f2dc053
SW		 929
930 dout("request_close_session mds%d state %s seq %lld\n",
931 session->s_mds, session_state_name(session->s_state),
932 session->s_seq);
933 msg = create_session_msg(CEPH_SESSION_REQUEST_CLOSE, session->s_seq);
a79832f2
SW		 934 if (!msg)
935 return -ENOMEM;
936 ceph_con_send(&session->s_con, msg);
937 return 0;
2f2dc053
SW		 938}
939
940/*
941 * Called with s_mutex held.
942 */
943static int __close_session(struct ceph_mds_client *mdsc,
944 struct ceph_mds_session *session)
945{
946 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
947 return 0;
948 session->s_state = CEPH_MDS_SESSION_CLOSING;
949 return request_close_session(mdsc, session);
950}
951
952/*
953 * Trim old(er) caps.
954 *
955 * Because we can't cache an inode without one or more caps, we do
956 * this indirectly: if a cap is unused, we prune its aliases, at which
957 * point the inode will hopefully get dropped to.
958 *
959 * Yes, this is a bit sloppy. Our only real goal here is to respond to
960 * memory pressure from the MDS, though, so it needn't be perfect.
961 */
962static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
963{
964 struct ceph_mds_session *session = arg;
965 struct ceph_inode_info *ci = ceph_inode(inode);
966 int used, oissued, mine;
967
968 if (session->s_trim_caps <= 0)
969 return -1;
970
971 spin_lock(&inode->i_lock);
972 mine = cap->issued | cap->implemented;
973 used = __ceph_caps_used(ci);
974 oissued = __ceph_caps_issued_other(ci, cap);
975
976 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s\n",
977 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
978 ceph_cap_string(used));
979 if (ci->i_dirty_caps)
980 goto out; /* dirty caps */
981 if ((used & ~oissued) & mine)
982 goto out; /* we need these caps */
983
984 session->s_trim_caps--;
985 if (oissued) {
986 /* we aren't the only cap.. just remove us */
7c1332b8 987 __ceph_remove_cap(cap);
2f2dc053
SW		 988 } else {
989 /* try to drop referring dentries */
990 spin_unlock(&inode->i_lock);
991 d_prune_aliases(inode);
992 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
993 inode, cap, atomic_read(&inode->i_count));
994 return 0;
995 }
996
997out:
998 spin_unlock(&inode->i_lock);
999 return 0;
1000}
1001
1002/*
1003 * Trim session cap count down to some max number.
1004 */
1005static int trim_caps(struct ceph_mds_client *mdsc,
1006 struct ceph_mds_session *session,
1007 int max_caps)
1008{
1009 int trim_caps = session->s_nr_caps - max_caps;
1010
1011 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1012 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1013 if (trim_caps > 0) {
1014 session->s_trim_caps = trim_caps;
1015 iterate_session_caps(session, trim_caps_cb, session);
1016 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1017 session->s_mds, session->s_nr_caps, max_caps,
1018 trim_caps - session->s_trim_caps);
5dacf091 1019 session->s_trim_caps = 0;
2f2dc053
SW		 1020 }
1021 return 0;
1022}
1023
1024/*
1025 * Allocate cap_release messages. If there is a partially full message
1026 * in the queue, try to allocate enough to cover it's remainder, so that
1027 * we can send it immediately.
1028 *
1029 * Called under s_mutex.
1030 */
1031static int add_cap_releases(struct ceph_mds_client *mdsc,
1032 struct ceph_mds_session *session,
1033 int extra)
1034{
1035 struct ceph_msg *msg;
1036 struct ceph_mds_cap_release *head;
1037 int err = -ENOMEM;
1038
1039 if (extra < 0)
6b805185 1040 extra = mdsc->client->mount_args->cap_release_safety;
2f2dc053
SW		 1041
1042 spin_lock(&session->s_cap_lock);
1043
1044 if (!list_empty(&session->s_cap_releases)) {
1045 msg = list_first_entry(&session->s_cap_releases,
1046 struct ceph_msg,
1047 list_head);
1048 head = msg->front.iov_base;
1049 extra += CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
1050 }
1051
1052 while (session->s_num_cap_releases < session->s_nr_caps + extra) {
1053 spin_unlock(&session->s_cap_lock);
bb257664 1054 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE);
2f2dc053
SW		 1055 if (!msg)
1056 goto out_unlocked;
1057 dout("add_cap_releases %p msg %p now %d\n", session, msg,
1058 (int)msg->front.iov_len);
1059 head = msg->front.iov_base;
1060 head->num = cpu_to_le32(0);
1061 msg->front.iov_len = sizeof(*head);
1062 spin_lock(&session->s_cap_lock);
1063 list_add(&msg->list_head, &session->s_cap_releases);
1064 session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
1065 }
1066
1067 if (!list_empty(&session->s_cap_releases)) {
1068 msg = list_first_entry(&session->s_cap_releases,
1069 struct ceph_msg,
1070 list_head);
1071 head = msg->front.iov_base;
1072 if (head->num) {
1073 dout(" queueing non-full %p (%d)\n", msg,
1074 le32_to_cpu(head->num));
1075 list_move_tail(&msg->list_head,
1076 &session->s_cap_releases_done);
1077 session->s_num_cap_releases -=
1078 CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
1079 }
1080 }
1081 err = 0;
1082 spin_unlock(&session->s_cap_lock);
1083out_unlocked:
1084 return err;
1085}
1086
1087/*
1088 * flush all dirty inode data to disk.
1089 *
1090 * returns true if we've flushed through want_flush_seq
1091 */
1092static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
1093{
1094 int mds, ret = 1;
1095
1096 dout("check_cap_flush want %lld\n", want_flush_seq);
1097 mutex_lock(&mdsc->mutex);
1098 for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
1099 struct ceph_mds_session *session = mdsc->sessions[mds];
1100
1101 if (!session)
1102 continue;
1103 get_session(session);
1104 mutex_unlock(&mdsc->mutex);
1105
1106 mutex_lock(&session->s_mutex);
1107 if (!list_empty(&session->s_cap_flushing)) {
1108 struct ceph_inode_info *ci =
1109 list_entry(session->s_cap_flushing.next,
1110 struct ceph_inode_info,
1111 i_flushing_item);
1112 struct inode *inode = &ci->vfs_inode;
1113
1114 spin_lock(&inode->i_lock);
1115 if (ci->i_cap_flush_seq <= want_flush_seq) {
1116 dout("check_cap_flush still flushing %p "
1117 "seq %lld <= %lld to mds%d\n", inode,
1118 ci->i_cap_flush_seq, want_flush_seq,
1119 session->s_mds);
1120 ret = 0;
1121 }
1122 spin_unlock(&inode->i_lock);
1123 }
1124 mutex_unlock(&session->s_mutex);
1125 ceph_put_mds_session(session);
1126
1127 if (!ret)
1128 return ret;
1129 mutex_lock(&mdsc->mutex);
1130 }
1131
1132 mutex_unlock(&mdsc->mutex);
1133 dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
1134 return ret;
1135}
1136
1137/*
1138 * called under s_mutex
1139 */
1140static void send_cap_releases(struct ceph_mds_client *mdsc,
1141 struct ceph_mds_session *session)
1142{
1143 struct ceph_msg *msg;
1144
1145 dout("send_cap_releases mds%d\n", session->s_mds);
0f8605f2
SW		 1146 spin_lock(&session->s_cap_lock);
1147 while (!list_empty(&session->s_cap_releases_done)) {
2f2dc053
SW		 1148 msg = list_first_entry(&session->s_cap_releases_done,
1149 struct ceph_msg, list_head);
1150 list_del_init(&msg->list_head);
1151 spin_unlock(&session->s_cap_lock);
1152 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1153 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1154 ceph_con_send(&session->s_con, msg);
0f8605f2 1155 spin_lock(&session->s_cap_lock);
2f2dc053
SW		 1156 }
1157 spin_unlock(&session->s_cap_lock);
1158}
1159
e01a5946
SW		 1160static void discard_cap_releases(struct ceph_mds_client *mdsc,
1161 struct ceph_mds_session *session)
1162{
1163 struct ceph_msg *msg;
1164 struct ceph_mds_cap_release *head;
1165 unsigned num;
1166
1167 dout("discard_cap_releases mds%d\n", session->s_mds);
1168 spin_lock(&session->s_cap_lock);
1169
1170 /* zero out the in-progress message */
1171 msg = list_first_entry(&session->s_cap_releases,
1172 struct ceph_msg, list_head);
1173 head = msg->front.iov_base;
1174 num = le32_to_cpu(head->num);
1175 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg, num);
1176 head->num = cpu_to_le32(0);
1177 session->s_num_cap_releases += num;
1178
1179 /* requeue completed messages */
1180 while (!list_empty(&session->s_cap_releases_done)) {
1181 msg = list_first_entry(&session->s_cap_releases_done,
1182 struct ceph_msg, list_head);
1183 list_del_init(&msg->list_head);
1184
1185 head = msg->front.iov_base;
1186 num = le32_to_cpu(head->num);
1187 dout("discard_cap_releases mds%d %p %u\n", session->s_mds, msg,
1188 num);
1189 session->s_num_cap_releases += num;
1190 head->num = cpu_to_le32(0);
1191 msg->front.iov_len = sizeof(*head);
1192 list_add(&msg->list_head, &session->s_cap_releases);
1193 }
1194
1195 spin_unlock(&session->s_cap_lock);
1196}
1197
2f2dc053
SW		 1198/*
1199 * requests
1200 */
1201
1202/*
1203 * Create an mds request.
1204 */
1205struct ceph_mds_request *
1206ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1207{
1208 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1209
1210 if (!req)
1211 return ERR_PTR(-ENOMEM);
1212
b4556396 1213 mutex_init(&req->r_fill_mutex);
2f2dc053
SW		 1214 req->r_started = jiffies;
1215 req->r_resend_mds = -1;
1216 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1217 req->r_fmode = -1;
153c8e6b 1218 kref_init(&req->r_kref);
2f2dc053
SW		 1219 INIT_LIST_HEAD(&req->r_wait);
1220 init_completion(&req->r_completion);
1221 init_completion(&req->r_safe_completion);
1222 INIT_LIST_HEAD(&req->r_unsafe_item);
1223
1224 req->r_op = op;
1225 req->r_direct_mode = mode;
1226 return req;
1227}
1228
1229/*
44ca18f2 1230 * return oldest (lowest) request, tid in request tree, 0 if none.
2f2dc053
SW		 1231 *
1232 * called under mdsc->mutex.
1233 */
44ca18f2
SW		 1234static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1235{
1236 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1237 return NULL;
1238 return rb_entry(rb_first(&mdsc->request_tree),
1239 struct ceph_mds_request, r_node);
1240}
1241
2f2dc053
SW		 1242static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1243{
44ca18f2
SW		 1244 struct ceph_mds_request *req = __get_oldest_req(mdsc);
1245
1246 if (req)
1247 return req->r_tid;
1248 return 0;
2f2dc053
SW		 1249}
1250
1251/*
1252 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1253 * on build_path_from_dentry in fs/cifs/dir.c.
1254 *
1255 * If @stop_on_nosnap, generate path relative to the first non-snapped
1256 * inode.
1257 *
1258 * Encode hidden .snap dirs as a double /, i.e.
1259 * foo/.snap/bar -> foo//bar
1260 */
1261char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1262 int stop_on_nosnap)
1263{
1264 struct dentry *temp;
1265 char *path;
1266 int len, pos;
1267
1268 if (dentry == NULL)
1269 return ERR_PTR(-EINVAL);
1270
1271retry:
1272 len = 0;
1273 for (temp = dentry; !IS_ROOT(temp);) {
1274 struct inode *inode = temp->d_inode;
1275 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1276 len++; /* slash only */
1277 else if (stop_on_nosnap && inode &&
1278 ceph_snap(inode) == CEPH_NOSNAP)
1279 break;
1280 else
1281 len += 1 + temp->d_name.len;
1282 temp = temp->d_parent;
1283 if (temp == NULL) {
1284 pr_err("build_path_dentry corrupt dentry %p\n", dentry);
1285 return ERR_PTR(-EINVAL);
1286 }
1287 }
1288 if (len)
1289 len--; /* no leading '/' */
1290
1291 path = kmalloc(len+1, GFP_NOFS);
1292 if (path == NULL)
1293 return ERR_PTR(-ENOMEM);
1294 pos = len;
1295 path[pos] = 0; /* trailing null */
1296 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1297 struct inode *inode = temp->d_inode;
1298
1299 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
104648ad 1300 dout("build_path path+%d: %p SNAPDIR\n",
2f2dc053
SW		 1301 pos, temp);
1302 } else if (stop_on_nosnap && inode &&
1303 ceph_snap(inode) == CEPH_NOSNAP) {
1304 break;
1305 } else {
1306 pos -= temp->d_name.len;
1307 if (pos < 0)
1308 break;
1309 strncpy(path + pos, temp->d_name.name,
1310 temp->d_name.len);
2f2dc053
SW		 1311 }
1312 if (pos)
1313 path[--pos] = '/';
1314 temp = temp->d_parent;
1315 if (temp == NULL) {
104648ad 1316 pr_err("build_path corrupt dentry\n");
2f2dc053
SW		 1317 kfree(path);
1318 return ERR_PTR(-EINVAL);
1319 }
1320 }
1321 if (pos != 0) {
104648ad 1322 pr_err("build_path did not end path lookup where "
2f2dc053
SW		 1323 "expected, namelen is %d, pos is %d\n", len, pos);
1324 /* presumably this is only possible if racing with a
1325 rename of one of the parent directories (we can not
1326 lock the dentries above us to prevent this, but
1327 retrying should be harmless) */
1328 kfree(path);
1329 goto retry;
1330 }
1331
1332 *base = ceph_ino(temp->d_inode);
1333 *plen = len;
104648ad 1334 dout("build_path on %p %d built %llx '%.*s'\n",
2f2dc053
SW		 1335 dentry, atomic_read(&dentry->d_count), *base, len, path);
1336 return path;
1337}
1338
1339static int build_dentry_path(struct dentry *dentry,
1340 const char **ppath, int *ppathlen, u64 *pino,
1341 int *pfreepath)
1342{
1343 char *path;
1344
1345 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1346 *pino = ceph_ino(dentry->d_parent->d_inode);
1347 *ppath = dentry->d_name.name;
1348 *ppathlen = dentry->d_name.len;
1349 return 0;
1350 }
1351 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1352 if (IS_ERR(path))
1353 return PTR_ERR(path);
1354 *ppath = path;
1355 *pfreepath = 1;
1356 return 0;
1357}
1358
1359static int build_inode_path(struct inode *inode,
1360 const char **ppath, int *ppathlen, u64 *pino,
1361 int *pfreepath)
1362{
1363 struct dentry *dentry;
1364 char *path;
1365
1366 if (ceph_snap(inode) == CEPH_NOSNAP) {
1367 *pino = ceph_ino(inode);
1368 *ppathlen = 0;
1369 return 0;
1370 }
1371 dentry = d_find_alias(inode);
1372 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1373 dput(dentry);
1374 if (IS_ERR(path))
1375 return PTR_ERR(path);
1376 *ppath = path;
1377 *pfreepath = 1;
1378 return 0;
1379}
1380
1381/*
1382 * request arguments may be specified via an inode *, a dentry *, or
1383 * an explicit ino+path.
1384 */
1385static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1386 const char *rpath, u64 rino,
1387 const char **ppath, int *pathlen,
1388 u64 *ino, int *freepath)
1389{
1390 int r = 0;
1391
1392 if (rinode) {
1393 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1394 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1395 ceph_snap(rinode));
1396 } else if (rdentry) {
1397 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1398 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1399 *ppath);
1400 } else if (rpath) {
1401 *ino = rino;
1402 *ppath = rpath;
1403 *pathlen = strlen(rpath);
1404 dout(" path %.*s\n", *pathlen, rpath);
1405 }
1406
1407 return r;
1408}
1409
1410/*
1411 * called under mdsc->mutex
1412 */
1413static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1414 struct ceph_mds_request *req,
1415 int mds)
1416{
1417 struct ceph_msg *msg;
1418 struct ceph_mds_request_head *head;
1419 const char *path1 = NULL;
1420 const char *path2 = NULL;
1421 u64 ino1 = 0, ino2 = 0;
1422 int pathlen1 = 0, pathlen2 = 0;
1423 int freepath1 = 0, freepath2 = 0;
1424 int len;
1425 u16 releases;
1426 void *p, *end;
1427 int ret;
1428
1429 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1430 req->r_path1, req->r_ino1.ino,
1431 &path1, &pathlen1, &ino1, &freepath1);
1432 if (ret < 0) {
1433 msg = ERR_PTR(ret);
1434 goto out;
1435 }
1436
1437 ret = set_request_path_attr(NULL, req->r_old_dentry,
1438 req->r_path2, req->r_ino2.ino,
1439 &path2, &pathlen2, &ino2, &freepath2);
1440 if (ret < 0) {
1441 msg = ERR_PTR(ret);
1442 goto out_free1;
1443 }
1444
1445 len = sizeof(*head) +
ac8839d7 1446 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
2f2dc053
SW		 1447
1448 /* calculate (max) length for cap releases */
1449 len += sizeof(struct ceph_mds_request_release) *
1450 (!!req->r_inode_drop + !!req->r_dentry_drop +
1451 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1452 if (req->r_dentry_drop)
1453 len += req->r_dentry->d_name.len;
1454 if (req->r_old_dentry_drop)
1455 len += req->r_old_dentry->d_name.len;
1456
bb257664 1457 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len);
a79832f2
SW		 1458 if (!msg) {
1459 msg = ERR_PTR(-ENOMEM);
2f2dc053 1460 goto out_free2;
a79832f2 1461 }
2f2dc053 1462
6df058c0
SW		 1463 msg->hdr.tid = cpu_to_le64(req->r_tid);
1464
2f2dc053
SW		 1465 head = msg->front.iov_base;
1466 p = msg->front.iov_base + sizeof(*head);
1467 end = msg->front.iov_base + msg->front.iov_len;
1468
1469 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1470 head->op = cpu_to_le32(req->r_op);
1471 head->caller_uid = cpu_to_le32(current_fsuid());
1472 head->caller_gid = cpu_to_le32(current_fsgid());
1473 head->args = req->r_args;
1474
1475 ceph_encode_filepath(&p, end, ino1, path1);
1476 ceph_encode_filepath(&p, end, ino2, path2);
1477
1478 /* cap releases */
1479 releases = 0;
1480 if (req->r_inode_drop)
1481 releases += ceph_encode_inode_release(&p,
1482 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1483 mds, req->r_inode_drop, req->r_inode_unless, 0);
1484 if (req->r_dentry_drop)
1485 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1486 mds, req->r_dentry_drop, req->r_dentry_unless);
1487 if (req->r_old_dentry_drop)
1488 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1489 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1490 if (req->r_old_inode_drop)
1491 releases += ceph_encode_inode_release(&p,
1492 req->r_old_dentry->d_inode,
1493 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1494 head->num_releases = cpu_to_le16(releases);
1495
1496 BUG_ON(p > end);
1497 msg->front.iov_len = p - msg->front.iov_base;
1498 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1499
1500 msg->pages = req->r_pages;
1501 msg->nr_pages = req->r_num_pages;
1502 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1503 msg->hdr.data_off = cpu_to_le16(0);
1504
1505out_free2:
1506 if (freepath2)
1507 kfree((char *)path2);
1508out_free1:
1509 if (freepath1)
1510 kfree((char *)path1);
1511out:
1512 return msg;
1513}
1514
1515/*
1516 * called under mdsc->mutex if error, under no mutex if
1517 * success.
1518 */
1519static void complete_request(struct ceph_mds_client *mdsc,
1520 struct ceph_mds_request *req)
1521{
1522 if (req->r_callback)
1523 req->r_callback(mdsc, req);
1524 else
1525 complete(&req->r_completion);
1526}
1527
1528/*
1529 * called under mdsc->mutex
1530 */
1531static int __prepare_send_request(struct ceph_mds_client *mdsc,
1532 struct ceph_mds_request *req,
1533 int mds)
1534{
1535 struct ceph_mds_request_head *rhead;
1536 struct ceph_msg *msg;
1537 int flags = 0;
1538
1539 req->r_mds = mds;
1540 req->r_attempts++;
1541 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1542 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1543
1544 if (req->r_request) {
1545 ceph_msg_put(req->r_request);
1546 req->r_request = NULL;
1547 }
1548 msg = create_request_message(mdsc, req, mds);
1549 if (IS_ERR(msg)) {
e1518c7c 1550 req->r_err = PTR_ERR(msg);
2f2dc053 1551 complete_request(mdsc, req);
a79832f2 1552 return PTR_ERR(msg);
2f2dc053
SW		 1553 }
1554 req->r_request = msg;
1555
1556 rhead = msg->front.iov_base;
2f2dc053
SW		 1557 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1558 if (req->r_got_unsafe)
1559 flags |= CEPH_MDS_FLAG_REPLAY;
1560 if (req->r_locked_dir)
1561 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1562 rhead->flags = cpu_to_le32(flags);
1563 rhead->num_fwd = req->r_num_fwd;
1564 rhead->num_retry = req->r_attempts - 1;
1565
1566 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1567
1568 if (req->r_target_inode && req->r_got_unsafe)
1569 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1570 else
1571 rhead->ino = 0;
1572 return 0;
1573}
1574
1575/*
1576 * send request, or put it on the appropriate wait list.
1577 */
1578static int __do_request(struct ceph_mds_client *mdsc,
1579 struct ceph_mds_request *req)
1580{
1581 struct ceph_mds_session *session = NULL;
1582 int mds = -1;
1583 int err = -EAGAIN;
1584
e1518c7c 1585 if (req->r_err || req->r_got_result)
2f2dc053
SW		 1586 goto out;
1587
1588 if (req->r_timeout &&
1589 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1590 dout("do_request timed out\n");
1591 err = -EIO;
1592 goto finish;
1593 }
1594
1595 mds = __choose_mds(mdsc, req);
1596 if (mds < 0 ||
1597 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1598 dout("do_request no mds or not active, waiting for map\n");
1599 list_add(&req->r_wait, &mdsc->waiting_for_map);
1600 goto out;
1601 }
1602
1603 /* get, open session */
1604 session = __ceph_lookup_mds_session(mdsc, mds);
9c423956 1605 if (!session) {
2f2dc053 1606 session = register_session(mdsc, mds);
9c423956
SW		 1607 if (IS_ERR(session)) {
1608 err = PTR_ERR(session);
1609 goto finish;
1610 }
1611 }
2f2dc053
SW		 1612 dout("do_request mds%d session %p state %s\n", mds, session,
1613 session_state_name(session->s_state));
1614 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
1615 session->s_state != CEPH_MDS_SESSION_HUNG) {
1616 if (session->s_state == CEPH_MDS_SESSION_NEW ||
1617 session->s_state == CEPH_MDS_SESSION_CLOSING)
1618 __open_session(mdsc, session);
1619 list_add(&req->r_wait, &session->s_waiting);
1620 goto out_session;
1621 }
1622
1623 /* send request */
1624 req->r_session = get_session(session);
1625 req->r_resend_mds = -1; /* forget any previous mds hint */
1626
1627 if (req->r_request_started == 0) /* note request start time */
1628 req->r_request_started = jiffies;
1629
1630 err = __prepare_send_request(mdsc, req, mds);
1631 if (!err) {
1632 ceph_msg_get(req->r_request);
1633 ceph_con_send(&session->s_con, req->r_request);
1634 }
1635
1636out_session:
1637 ceph_put_mds_session(session);
1638out:
1639 return err;
1640
1641finish:
e1518c7c 1642 req->r_err = err;
2f2dc053
SW		 1643 complete_request(mdsc, req);
1644 goto out;
1645}
1646
1647/*
1648 * called under mdsc->mutex
1649 */
1650static void __wake_requests(struct ceph_mds_client *mdsc,
1651 struct list_head *head)
1652{
1653 struct ceph_mds_request *req, *nreq;
1654
1655 list_for_each_entry_safe(req, nreq, head, r_wait) {
1656 list_del_init(&req->r_wait);
1657 __do_request(mdsc, req);
1658 }
1659}
1660
1661/*
1662 * Wake up threads with requests pending for @mds, so that they can
29790f26 1663 * resubmit their requests to a possibly different mds.
2f2dc053 1664 */
29790f26 1665static void kick_requests(struct ceph_mds_client *mdsc, int mds)
2f2dc053 1666{
44ca18f2
SW		 1667 struct ceph_mds_request *req;
1668 struct rb_node *p;
2f2dc053
SW		 1669
1670 dout("kick_requests mds%d\n", mds);
44ca18f2
SW		 1671 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
1672 req = rb_entry(p, struct ceph_mds_request, r_node);
1673 if (req->r_got_unsafe)
1674 continue;
1675 if (req->r_session &&
1676 req->r_session->s_mds == mds) {
1677 dout(" kicking tid %llu\n", req->r_tid);
1678 put_request_session(req);
1679 __do_request(mdsc, req);
2f2dc053
SW		 1680 }
1681 }
1682}
1683
1684void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
1685 struct ceph_mds_request *req)
1686{
1687 dout("submit_request on %p\n", req);
1688 mutex_lock(&mdsc->mutex);
1689 __register_request(mdsc, req, NULL);
1690 __do_request(mdsc, req);
1691 mutex_unlock(&mdsc->mutex);
1692}
1693
1694/*
1695 * Synchrously perform an mds request. Take care of all of the
1696 * session setup, forwarding, retry details.
1697 */
1698int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
1699 struct inode *dir,
1700 struct ceph_mds_request *req)
1701{
1702 int err;
1703
1704 dout("do_request on %p\n", req);
1705
1706 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
1707 if (req->r_inode)
1708 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
1709 if (req->r_locked_dir)
1710 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
1711 if (req->r_old_dentry)
1712 ceph_get_cap_refs(
1713 ceph_inode(req->r_old_dentry->d_parent->d_inode),
1714 CEPH_CAP_PIN);
1715
1716 /* issue */
1717 mutex_lock(&mdsc->mutex);
1718 __register_request(mdsc, req, dir);
1719 __do_request(mdsc, req);
1720
e1518c7c
SW		 1721 if (req->r_err) {
1722 err = req->r_err;
1723 __unregister_request(mdsc, req);
1724 dout("do_request early error %d\n", err);
1725 goto out;
2f2dc053
SW		 1726 }
1727
e1518c7c
SW		 1728 /* wait */
1729 mutex_unlock(&mdsc->mutex);
1730 dout("do_request waiting\n");
1731 if (req->r_timeout) {
1732 err = (long)wait_for_completion_interruptible_timeout(
1733 &req->r_completion, req->r_timeout);
1734 if (err == 0)
1735 err = -EIO;
1736 } else {
1737 err = wait_for_completion_interruptible(&req->r_completion);
1738 }
1739 dout("do_request waited, got %d\n", err);
1740 mutex_lock(&mdsc->mutex);
5b1daecd 1741
e1518c7c
SW		 1742 /* only abort if we didn't race with a real reply */
1743 if (req->r_got_result) {
1744 err = le32_to_cpu(req->r_reply_info.head->result);
1745 } else if (err < 0) {
1746 dout("aborted request %lld with %d\n", req->r_tid, err);
b4556396
SW		 1747
1748 /*
1749 * ensure we aren't running concurrently with
1750 * ceph_fill_trace or ceph_readdir_prepopulate, which
1751 * rely on locks (dir mutex) held by our caller.
1752 */
1753 mutex_lock(&req->r_fill_mutex);
e1518c7c
SW		 1754 req->r_err = err;
1755 req->r_aborted = true;
b4556396 1756 mutex_unlock(&req->r_fill_mutex);
5b1daecd 1757
e1518c7c
SW		 1758 if (req->r_locked_dir &&
1759 (req->r_op & CEPH_MDS_OP_WRITE)) {
1760 struct ceph_inode_info *ci =
1761 ceph_inode(req->r_locked_dir);
1762
81a6cf2d 1763 dout("aborted, clearing I_COMPLETE on %p, leases\n",
e1518c7c
SW		 1764 req->r_locked_dir);
1765 spin_lock(&req->r_locked_dir->i_lock);
1766 ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
1767 ci->i_release_count++;
1768 spin_unlock(&req->r_locked_dir->i_lock);
81a6cf2d
SW		 1769
1770 if (req->r_dentry)
1771 ceph_invalidate_dentry_lease(req->r_dentry);
1772 if (req->r_old_dentry)
1773 ceph_invalidate_dentry_lease(req->r_old_dentry);
5b1daecd 1774 }
2f2dc053 1775 } else {
e1518c7c 1776 err = req->r_err;
2f2dc053 1777 }
2f2dc053 1778
e1518c7c
SW		 1779out:
1780 mutex_unlock(&mdsc->mutex);
2f2dc053
SW		 1781 dout("do_request %p done, result %d\n", req, err);
1782 return err;
1783}
1784
1785/*
1786 * Handle mds reply.
1787 *
1788 * We take the session mutex and parse and process the reply immediately.
1789 * This preserves the logical ordering of replies, capabilities, etc., sent
1790 * by the MDS as they are applied to our local cache.
1791 */
1792static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
1793{
1794 struct ceph_mds_client *mdsc = session->s_mdsc;
1795 struct ceph_mds_request *req;
1796 struct ceph_mds_reply_head *head = msg->front.iov_base;
1797 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
1798 u64 tid;
1799 int err, result;
2600d2dd 1800 int mds = session->s_mds;
2f2dc053 1801
2f2dc053
SW		 1802 if (msg->front.iov_len < sizeof(*head)) {
1803 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
9ec7cab1 1804 ceph_msg_dump(msg);
2f2dc053
SW		 1805 return;
1806 }
1807
1808 /* get request, session */
6df058c0 1809 tid = le64_to_cpu(msg->hdr.tid);
2f2dc053
SW		 1810 mutex_lock(&mdsc->mutex);
1811 req = __lookup_request(mdsc, tid);
1812 if (!req) {
1813 dout("handle_reply on unknown tid %llu\n", tid);
1814 mutex_unlock(&mdsc->mutex);
1815 return;
1816 }
1817 dout("handle_reply %p\n", req);
2f2dc053
SW		 1818
1819 /* correct session? */
d96d6049 1820 if (req->r_session != session) {
2f2dc053
SW		 1821 pr_err("mdsc_handle_reply got %llu on session mds%d"
1822 " not mds%d\n", tid, session->s_mds,
1823 req->r_session ? req->r_session->s_mds : -1);
1824 mutex_unlock(&mdsc->mutex);
1825 goto out;
1826 }
1827
1828 /* dup? */
1829 if ((req->r_got_unsafe && !head->safe) ||
1830 (req->r_got_safe && head->safe)) {
1831 pr_warning("got a dup %s reply on %llu from mds%d\n",
1832 head->safe ? "safe" : "unsafe", tid, mds);
1833 mutex_unlock(&mdsc->mutex);
1834 goto out;
1835 }
1836
1837 result = le32_to_cpu(head->result);
1838
1839 /*
1840 * Tolerate 2 consecutive ESTALEs from the same mds.
1841 * FIXME: we should be looking at the cap migrate_seq.
1842 */
1843 if (result == -ESTALE) {
1844 req->r_direct_mode = USE_AUTH_MDS;
1845 req->r_num_stale++;
1846 if (req->r_num_stale <= 2) {
1847 __do_request(mdsc, req);
1848 mutex_unlock(&mdsc->mutex);
1849 goto out;
1850 }
1851 } else {
1852 req->r_num_stale = 0;
1853 }
1854
1855 if (head->safe) {
1856 req->r_got_safe = true;
1857 __unregister_request(mdsc, req);
1858 complete(&req->r_safe_completion);
1859
1860 if (req->r_got_unsafe) {
1861 /*
1862 * We already handled the unsafe response, now do the
1863 * cleanup. No need to examine the response; the MDS
1864 * doesn't include any result info in the safe
1865 * response. And even if it did, there is nothing
1866 * useful we could do with a revised return value.
1867 */
1868 dout("got safe reply %llu, mds%d\n", tid, mds);
1869 list_del_init(&req->r_unsafe_item);
1870
1871 /* last unsafe request during umount? */
44ca18f2 1872 if (mdsc->stopping && !__get_oldest_req(mdsc))
2f2dc053
SW		 1873 complete(&mdsc->safe_umount_waiters);
1874 mutex_unlock(&mdsc->mutex);
1875 goto out;
1876 }
e1518c7c 1877 } else {
2f2dc053
SW		 1878 req->r_got_unsafe = true;
1879 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
1880 }
1881
1882 dout("handle_reply tid %lld result %d\n", tid, result);
1883 rinfo = &req->r_reply_info;
1884 err = parse_reply_info(msg, rinfo);
1885 mutex_unlock(&mdsc->mutex);
1886
1887 mutex_lock(&session->s_mutex);
1888 if (err < 0) {
1889 pr_err("mdsc_handle_reply got corrupt reply mds%d\n", mds);
9ec7cab1 1890 ceph_msg_dump(msg);
2f2dc053
SW		 1891 goto out_err;
1892 }
1893
1894 /* snap trace */
1895 if (rinfo->snapblob_len) {
1896 down_write(&mdsc->snap_rwsem);
1897 ceph_update_snap_trace(mdsc, rinfo->snapblob,
1898 rinfo->snapblob + rinfo->snapblob_len,
1899 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
1900 downgrade_write(&mdsc->snap_rwsem);
1901 } else {
1902 down_read(&mdsc->snap_rwsem);
1903 }
1904
1905 /* insert trace into our cache */
b4556396 1906 mutex_lock(&req->r_fill_mutex);
2f2dc053
SW		 1907 err = ceph_fill_trace(mdsc->client->sb, req, req->r_session);
1908 if (err == 0) {
1909 if (result == 0 && rinfo->dir_nr)
1910 ceph_readdir_prepopulate(req, req->r_session);
1911 ceph_unreserve_caps(&req->r_caps_reservation);
1912 }
b4556396 1913 mutex_unlock(&req->r_fill_mutex);
2f2dc053
SW		 1914
1915 up_read(&mdsc->snap_rwsem);
1916out_err:
e1518c7c
SW		 1917 mutex_lock(&mdsc->mutex);
1918 if (!req->r_aborted) {
1919 if (err) {
1920 req->r_err = err;
1921 } else {
1922 req->r_reply = msg;
1923 ceph_msg_get(msg);
1924 req->r_got_result = true;
1925 }
2f2dc053 1926 } else {
e1518c7c 1927 dout("reply arrived after request %lld was aborted\n", tid);
2f2dc053 1928 }
e1518c7c 1929 mutex_unlock(&mdsc->mutex);
2f2dc053
SW		 1930
1931 add_cap_releases(mdsc, req->r_session, -1);
1932 mutex_unlock(&session->s_mutex);
1933
1934 /* kick calling process */
1935 complete_request(mdsc, req);
1936out:
1937 ceph_mdsc_put_request(req);
1938 return;
1939}
1940
1941
1942
1943/*
1944 * handle mds notification that our request has been forwarded.
1945 */
2600d2dd
SW		 1946static void handle_forward(struct ceph_mds_client *mdsc,
1947 struct ceph_mds_session *session,
1948 struct ceph_msg *msg)
2f2dc053
SW		 1949{
1950 struct ceph_mds_request *req;
a1ea787c 1951 u64 tid = le64_to_cpu(msg->hdr.tid);
2f2dc053
SW		 1952 u32 next_mds;
1953 u32 fwd_seq;
2f2dc053
SW		 1954 int err = -EINVAL;
1955 void *p = msg->front.iov_base;
1956 void *end = p + msg->front.iov_len;
2f2dc053 1957
a1ea787c 1958 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
c89136ea
SW		 1959 next_mds = ceph_decode_32(&p);
1960 fwd_seq = ceph_decode_32(&p);
2f2dc053
SW		 1961
1962 mutex_lock(&mdsc->mutex);
1963 req = __lookup_request(mdsc, tid);
1964 if (!req) {
080af17e 1965 dout("forward %llu to mds%d - req dne\n", tid, next_mds);
2f2dc053
SW		 1966 goto out; /* dup reply? */
1967 }
1968
2f2dc053
SW		 1969 if (fwd_seq <= req->r_num_fwd) {
1970 dout("forward %llu to mds%d - old seq %d <= %d\n",
1971 tid, next_mds, req->r_num_fwd, fwd_seq);
1972 } else {
1973 /* resend. forward race not possible; mds would drop */
1974 dout("forward %llu to mds%d (we resend)\n", tid, next_mds);
1975 req->r_num_fwd = fwd_seq;
1976 req->r_resend_mds = next_mds;
1977 put_request_session(req);
1978 __do_request(mdsc, req);
1979 }
1980 ceph_mdsc_put_request(req);
1981out:
1982 mutex_unlock(&mdsc->mutex);
1983 return;
1984
1985bad:
1986 pr_err("mdsc_handle_forward decode error err=%d\n", err);
1987}
1988
1989/*
1990 * handle a mds session control message
1991 */
1992static void handle_session(struct ceph_mds_session *session,
1993 struct ceph_msg *msg)
1994{
1995 struct ceph_mds_client *mdsc = session->s_mdsc;
1996 u32 op;
1997 u64 seq;
2600d2dd 1998 int mds = session->s_mds;
2f2dc053
SW		 1999 struct ceph_mds_session_head *h = msg->front.iov_base;
2000 int wake = 0;
2001
2f2dc053
SW		 2002 /* decode */
2003 if (msg->front.iov_len != sizeof(*h))
2004 goto bad;
2005 op = le32_to_cpu(h->op);
2006 seq = le64_to_cpu(h->seq);
2007
2008 mutex_lock(&mdsc->mutex);
2600d2dd
SW		 2009 if (op == CEPH_SESSION_CLOSE)
2010 __unregister_session(mdsc, session);
2f2dc053
SW		 2011 /* FIXME: this ttl calculation is generous */
2012 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
2013 mutex_unlock(&mdsc->mutex);
2014
2015 mutex_lock(&session->s_mutex);
2016
2017 dout("handle_session mds%d %s %p state %s seq %llu\n",
2018 mds, ceph_session_op_name(op), session,
2019 session_state_name(session->s_state), seq);
2020
2021 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
2022 session->s_state = CEPH_MDS_SESSION_OPEN;
2023 pr_info("mds%d came back\n", session->s_mds);
2024 }
2025
2026 switch (op) {
2027 case CEPH_SESSION_OPEN:
29790f26
SW		 2028 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2029 pr_info("mds%d reconnect success\n", session->s_mds);
2f2dc053
SW		 2030 session->s_state = CEPH_MDS_SESSION_OPEN;
2031 renewed_caps(mdsc, session, 0);
2032 wake = 1;
2033 if (mdsc->stopping)
2034 __close_session(mdsc, session);
2035 break;
2036
2037 case CEPH_SESSION_RENEWCAPS:
2038 if (session->s_renew_seq == seq)
2039 renewed_caps(mdsc, session, 1);
2040 break;
2041
2042 case CEPH_SESSION_CLOSE:
29790f26
SW		 2043 if (session->s_state == CEPH_MDS_SESSION_RECONNECTING)
2044 pr_info("mds%d reconnect denied\n", session->s_mds);
2f2dc053
SW		 2045 remove_session_caps(session);
2046 wake = 1; /* for good measure */
2047 complete(&mdsc->session_close_waiters);
29790f26 2048 kick_requests(mdsc, mds);
2f2dc053
SW		 2049 break;
2050
2051 case CEPH_SESSION_STALE:
2052 pr_info("mds%d caps went stale, renewing\n",
2053 session->s_mds);
2054 spin_lock(&session->s_cap_lock);
2055 session->s_cap_gen++;
2056 session->s_cap_ttl = 0;
2057 spin_unlock(&session->s_cap_lock);
2058 send_renew_caps(mdsc, session);
2059 break;
2060
2061 case CEPH_SESSION_RECALL_STATE:
2062 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2063 break;
2064
2065 default:
2066 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2067 WARN_ON(1);
2068 }
2069
2070 mutex_unlock(&session->s_mutex);
2071 if (wake) {
2072 mutex_lock(&mdsc->mutex);
2073 __wake_requests(mdsc, &session->s_waiting);
2074 mutex_unlock(&mdsc->mutex);
2075 }
2076 return;
2077
2078bad:
2079 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2080 (int)msg->front.iov_len);
9ec7cab1 2081 ceph_msg_dump(msg);
2f2dc053
SW		 2082 return;
2083}
2084
2085
2086/*
2087 * called under session->mutex.
2088 */
2089static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2090 struct ceph_mds_session *session)
2091{
2092 struct ceph_mds_request *req, *nreq;
2093 int err;
2094
2095 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2096
2097 mutex_lock(&mdsc->mutex);
2098 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2099 err = __prepare_send_request(mdsc, req, session->s_mds);
2100 if (!err) {
2101 ceph_msg_get(req->r_request);
2102 ceph_con_send(&session->s_con, req->r_request);
2103 }
2104 }
2105 mutex_unlock(&mdsc->mutex);
2106}
2107
2108/*
2109 * Encode information about a cap for a reconnect with the MDS.
2110 */
2f2dc053
SW		 2111static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2112 void *arg)
2113{
93cea5be 2114 struct ceph_mds_cap_reconnect rec;
2f2dc053 2115 struct ceph_inode_info *ci;
93cea5be 2116 struct ceph_pagelist *pagelist = arg;
2f2dc053
SW		 2117 char *path;
2118 int pathlen, err;
2119 u64 pathbase;
2120 struct dentry *dentry;
2121
2122 ci = cap->ci;
2123
2124 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2125 inode, ceph_vinop(inode), cap, cap->cap_id,
2126 ceph_cap_string(cap->issued));
93cea5be
SW		 2127 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2128 if (err)
2129 return err;
2f2dc053
SW		 2130
2131 dentry = d_find_alias(inode);
2132 if (dentry) {
2133 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2134 if (IS_ERR(path)) {
2135 err = PTR_ERR(path);
2136 BUG_ON(err);
2137 }
2138 } else {
2139 path = NULL;
2140 pathlen = 0;
2141 }
93cea5be
SW		 2142 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2143 if (err)
2144 goto out;
2f2dc053 2145
2f2dc053
SW		 2146 spin_lock(&inode->i_lock);
2147 cap->seq = 0; /* reset cap seq */
2148 cap->issue_seq = 0; /* and issue_seq */
93cea5be
SW		 2149 rec.cap_id = cpu_to_le64(cap->cap_id);
2150 rec.pathbase = cpu_to_le64(pathbase);
2151 rec.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2152 rec.issued = cpu_to_le32(cap->issued);
2153 rec.size = cpu_to_le64(inode->i_size);
2154 ceph_encode_timespec(&rec.mtime, &inode->i_mtime);
2155 ceph_encode_timespec(&rec.atime, &inode->i_atime);
2156 rec.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2f2dc053
SW		 2157 spin_unlock(&inode->i_lock);
2158
93cea5be
SW		 2159 err = ceph_pagelist_append(pagelist, &rec, sizeof(rec));
2160
2161out:
2f2dc053
SW		 2162 kfree(path);
2163 dput(dentry);
93cea5be 2164 return err;
2f2dc053
SW		 2165}
2166
2167
2168/*
2169 * If an MDS fails and recovers, clients need to reconnect in order to
2170 * reestablish shared state. This includes all caps issued through
2171 * this session _and_ the snap_realm hierarchy. Because it's not
2172 * clear which snap realms the mds cares about, we send everything we
2173 * know about.. that ensures we'll then get any new info the
2174 * recovering MDS might have.
2175 *
2176 * This is a relatively heavyweight operation, but it's rare.
2177 *
2178 * called with mdsc->mutex held.
2179 */
2180static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
2181{
93cea5be 2182 struct ceph_mds_session *session = NULL;
2f2dc053 2183 struct ceph_msg *reply;
a105f00c 2184 struct rb_node *p;
9abf82b8 2185 int err = -ENOMEM;
93cea5be 2186 struct ceph_pagelist *pagelist;
2f2dc053
SW		 2187
2188 pr_info("reconnect to recovering mds%d\n", mds);
2189
93cea5be
SW		 2190 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2191 if (!pagelist)
2192 goto fail_nopagelist;
2193 ceph_pagelist_init(pagelist);
2194
a79832f2 2195 err = -ENOMEM;
bb257664 2196 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0);
a79832f2 2197 if (!reply)
93cea5be 2198 goto fail_nomsg;
93cea5be 2199
2f2dc053
SW		 2200 /* find session */
2201 session = __ceph_lookup_mds_session(mdsc, mds);
2202 mutex_unlock(&mdsc->mutex); /* drop lock for duration */
2203
2204 if (session) {
2205 mutex_lock(&session->s_mutex);
2206
2207 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2208 session->s_seq = 0;
2209
2210 ceph_con_open(&session->s_con,
2211 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2212
2213 /* replay unsafe requests */
2214 replay_unsafe_requests(mdsc, session);
2f2dc053
SW		 2215 } else {
2216 dout("no session for mds%d, will send short reconnect\n",
2217 mds);
2218 }
2219
2220 down_read(&mdsc->snap_rwsem);
2221
93cea5be 2222 if (!session)
2f2dc053 2223 goto send;
2f2dc053
SW		 2224 dout("session %p state %s\n", session,
2225 session_state_name(session->s_state));
2226
e01a5946
SW		 2227 /* drop old cap expires; we're about to reestablish that state */
2228 discard_cap_releases(mdsc, session);
2229
2f2dc053 2230 /* traverse this session's caps */
93cea5be
SW		 2231 err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
2232 if (err)
2233 goto fail;
2234 err = iterate_session_caps(session, encode_caps_cb, pagelist);
2f2dc053 2235 if (err < 0)
9abf82b8 2236 goto fail;
2f2dc053
SW		 2237
2238 /*
2239 * snaprealms. we provide mds with the ino, seq (version), and
2240 * parent for all of our realms. If the mds has any newer info,
2241 * it will tell us.
2242 */
a105f00c
SW		 2243 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2244 struct ceph_snap_realm *realm =
2245 rb_entry(p, struct ceph_snap_realm, node);
93cea5be 2246 struct ceph_mds_snaprealm_reconnect sr_rec;
2f2dc053
SW		 2247
2248 dout(" adding snap realm %llx seq %lld parent %llx\n",
2249 realm->ino, realm->seq, realm->parent_ino);
93cea5be
SW		 2250 sr_rec.ino = cpu_to_le64(realm->ino);
2251 sr_rec.seq = cpu_to_le64(realm->seq);
2252 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2253 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2254 if (err)
2255 goto fail;
2f2dc053 2256 }
2f2dc053
SW		 2257
2258send:
93cea5be
SW		 2259 reply->pagelist = pagelist;
2260 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2261 reply->nr_pages = calc_pages_for(0, pagelist->length);
2f2dc053
SW		 2262 ceph_con_send(&session->s_con, reply);
2263
9abf82b8
SW		 2264 mutex_unlock(&session->s_mutex);
2265
2266 mutex_lock(&mdsc->mutex);
2267 __wake_requests(mdsc, &session->s_waiting);
2268 mutex_unlock(&mdsc->mutex);
2269
2270 ceph_put_mds_session(session);
2f2dc053 2271
2f2dc053 2272 up_read(&mdsc->snap_rwsem);
2f2dc053
SW		 2273 mutex_lock(&mdsc->mutex);
2274 return;
2275
93cea5be 2276fail:
2f2dc053 2277 ceph_msg_put(reply);
9abf82b8
SW		 2278 up_read(&mdsc->snap_rwsem);
2279 mutex_unlock(&session->s_mutex);
2280 ceph_put_mds_session(session);
93cea5be
SW		 2281fail_nomsg:
2282 ceph_pagelist_release(pagelist);
2283 kfree(pagelist);
2284fail_nopagelist:
9abf82b8
SW		 2285 pr_err("error %d preparing reconnect for mds%d\n", err, mds);
2286 mutex_lock(&mdsc->mutex);
2287 return;
2f2dc053
SW		 2288}
2289
2290
2291/*
2292 * compare old and new mdsmaps, kicking requests
2293 * and closing out old connections as necessary
2294 *
2295 * called under mdsc->mutex.
2296 */
2297static void check_new_map(struct ceph_mds_client *mdsc,
2298 struct ceph_mdsmap *newmap,
2299 struct ceph_mdsmap *oldmap)
2300{
2301 int i;
2302 int oldstate, newstate;
2303 struct ceph_mds_session *s;
2304
2305 dout("check_new_map new %u old %u\n",
2306 newmap->m_epoch, oldmap->m_epoch);
2307
2308 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2309 if (mdsc->sessions[i] == NULL)
2310 continue;
2311 s = mdsc->sessions[i];
2312 oldstate = ceph_mdsmap_get_state(oldmap, i);
2313 newstate = ceph_mdsmap_get_state(newmap, i);
2314
2315 dout("check_new_map mds%d state %s -> %s (session %s)\n",
2316 i, ceph_mds_state_name(oldstate),
2317 ceph_mds_state_name(newstate),
2318 session_state_name(s->s_state));
2319
2320 if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
2321 ceph_mdsmap_get_addr(newmap, i),
2322 sizeof(struct ceph_entity_addr))) {
2323 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2324 /* the session never opened, just close it
2325 * out now */
2326 __wake_requests(mdsc, &s->s_waiting);
2600d2dd 2327 __unregister_session(mdsc, s);
2f2dc053
SW		 2328 } else {
2329 /* just close it */
2330 mutex_unlock(&mdsc->mutex);
2331 mutex_lock(&s->s_mutex);
2332 mutex_lock(&mdsc->mutex);
2333 ceph_con_close(&s->s_con);
2334 mutex_unlock(&s->s_mutex);
2335 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2336 }
2337
2338 /* kick any requests waiting on the recovering mds */
29790f26 2339 kick_requests(mdsc, i);
2f2dc053
SW		 2340 } else if (oldstate == newstate) {
2341 continue; /* nothing new with this mds */
2342 }
2343
2344 /*
2345 * send reconnect?
2346 */
2347 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2348 newstate >= CEPH_MDS_STATE_RECONNECT)
2349 send_mds_reconnect(mdsc, i);
2350
2351 /*
29790f26 2352 * kick request on any mds that has gone active.
2f2dc053
SW		 2353 */
2354 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2355 newstate >= CEPH_MDS_STATE_ACTIVE) {
29790f26
SW		 2356 if (oldstate != CEPH_MDS_STATE_CREATING &&
2357 oldstate != CEPH_MDS_STATE_STARTING)
2358 pr_info("mds%d recovery completed\n", s->s_mds);
2359 kick_requests(mdsc, i);
2f2dc053 2360 ceph_kick_flushing_caps(mdsc, s);
0dc2570f 2361 wake_up_session_caps(s, 1);
2f2dc053
SW		 2362 }
2363 }
2364}
2365
2366
2367
2368/*
2369 * leases
2370 */
2371
2372/*
2373 * caller must hold session s_mutex, dentry->d_lock
2374 */
2375void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2376{
2377 struct ceph_dentry_info *di = ceph_dentry(dentry);
2378
2379 ceph_put_mds_session(di->lease_session);
2380 di->lease_session = NULL;
2381}
2382
2600d2dd
SW		 2383static void handle_lease(struct ceph_mds_client *mdsc,
2384 struct ceph_mds_session *session,
2385 struct ceph_msg *msg)
2f2dc053
SW		 2386{
2387 struct super_block *sb = mdsc->client->sb;
2388 struct inode *inode;
2f2dc053
SW		 2389 struct ceph_inode_info *ci;
2390 struct dentry *parent, *dentry;
2391 struct ceph_dentry_info *di;
2600d2dd 2392 int mds = session->s_mds;
2f2dc053
SW		 2393 struct ceph_mds_lease *h = msg->front.iov_base;
2394 struct ceph_vino vino;
2395 int mask;
2396 struct qstr dname;
2397 int release = 0;
2398
2f2dc053
SW		 2399 dout("handle_lease from mds%d\n", mds);
2400
2401 /* decode */
2402 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2403 goto bad;
2404 vino.ino = le64_to_cpu(h->ino);
2405 vino.snap = CEPH_NOSNAP;
2406 mask = le16_to_cpu(h->mask);
2407 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2408 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2409 if (dname.len != get_unaligned_le32(h+1))
2410 goto bad;
2411
2f2dc053
SW		 2412 mutex_lock(&session->s_mutex);
2413 session->s_seq++;
2414
2415 /* lookup inode */
2416 inode = ceph_find_inode(sb, vino);
2417 dout("handle_lease '%s', mask %d, ino %llx %p\n",
2418 ceph_lease_op_name(h->action), mask, vino.ino, inode);
2419 if (inode == NULL) {
2420 dout("handle_lease no inode %llx\n", vino.ino);
2421 goto release;
2422 }
2423 ci = ceph_inode(inode);
2424
2425 /* dentry */
2426 parent = d_find_alias(inode);
2427 if (!parent) {
2428 dout("no parent dentry on inode %p\n", inode);
2429 WARN_ON(1);
2430 goto release; /* hrm... */
2431 }
2432 dname.hash = full_name_hash(dname.name, dname.len);
2433 dentry = d_lookup(parent, &dname);
2434 dput(parent);
2435 if (!dentry)
2436 goto release;
2437
2438 spin_lock(&dentry->d_lock);
2439 di = ceph_dentry(dentry);
2440 switch (h->action) {
2441 case CEPH_MDS_LEASE_REVOKE:
2442 if (di && di->lease_session == session) {
2443 h->seq = cpu_to_le32(di->lease_seq);
2444 __ceph_mdsc_drop_dentry_lease(dentry);
2445 }
2446 release = 1;
2447 break;
2448
2449 case CEPH_MDS_LEASE_RENEW:
2450 if (di && di->lease_session == session &&
2451 di->lease_gen == session->s_cap_gen &&
2452 di->lease_renew_from &&
2453 di->lease_renew_after == 0) {
2454 unsigned long duration =
2455 le32_to_cpu(h->duration_ms) * HZ / 1000;
2456
2457 di->lease_seq = le32_to_cpu(h->seq);
2458 dentry->d_time = di->lease_renew_from + duration;
2459 di->lease_renew_after = di->lease_renew_from +
2460 (duration >> 1);
2461 di->lease_renew_from = 0;
2462 }
2463 break;
2464 }
2465 spin_unlock(&dentry->d_lock);
2466 dput(dentry);
2467
2468 if (!release)
2469 goto out;
2470
2471release:
2472 /* let's just reuse the same message */
2473 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2474 ceph_msg_get(msg);
2475 ceph_con_send(&session->s_con, msg);
2476
2477out:
2478 iput(inode);
2479 mutex_unlock(&session->s_mutex);
2f2dc053
SW		 2480 return;
2481
2482bad:
2483 pr_err("corrupt lease message\n");
9ec7cab1 2484 ceph_msg_dump(msg);
2f2dc053
SW		 2485}
2486
2487void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
2488 struct inode *inode,
2489 struct dentry *dentry, char action,
2490 u32 seq)
2491{
2492 struct ceph_msg *msg;
2493 struct ceph_mds_lease *lease;
2494 int len = sizeof(*lease) + sizeof(u32);
2495 int dnamelen = 0;
2496
2497 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
2498 inode, dentry, ceph_lease_op_name(action), session->s_mds);
2499 dnamelen = dentry->d_name.len;
2500 len += dnamelen;
2501
bb257664 2502 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len);
a79832f2 2503 if (!msg)
2f2dc053
SW		 2504 return;
2505 lease = msg->front.iov_base;
2506 lease->action = action;
2507 lease->mask = cpu_to_le16(CEPH_LOCK_DN);
2508 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
2509 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
2510 lease->seq = cpu_to_le32(seq);
2511 put_unaligned_le32(dnamelen, lease + 1);
2512 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
2513
2514 /*
2515 * if this is a preemptive lease RELEASE, no need to
2516 * flush request stream, since the actual request will
2517 * soon follow.
2518 */
2519 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
2520
2521 ceph_con_send(&session->s_con, msg);
2522}
2523
2524/*
2525 * Preemptively release a lease we expect to invalidate anyway.
2526 * Pass @inode always, @dentry is optional.
2527 */
2528void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
2529 struct dentry *dentry, int mask)
2530{
2531 struct ceph_dentry_info *di;
2532 struct ceph_mds_session *session;
2533 u32 seq;
2534
2535 BUG_ON(inode == NULL);
2536 BUG_ON(dentry == NULL);
2537 BUG_ON(mask != CEPH_LOCK_DN);
2538
2539 /* is dentry lease valid? */
2540 spin_lock(&dentry->d_lock);
2541 di = ceph_dentry(dentry);
2542 if (!di || !di->lease_session ||
2543 di->lease_session->s_mds < 0 ||
2544 di->lease_gen != di->lease_session->s_cap_gen ||
2545 !time_before(jiffies, dentry->d_time)) {
2546 dout("lease_release inode %p dentry %p -- "
2547 "no lease on %d\n",
2548 inode, dentry, mask);
2549 spin_unlock(&dentry->d_lock);
2550 return;
2551 }
2552
2553 /* we do have a lease on this dentry; note mds and seq */
2554 session = ceph_get_mds_session(di->lease_session);
2555 seq = di->lease_seq;
2556 __ceph_mdsc_drop_dentry_lease(dentry);
2557 spin_unlock(&dentry->d_lock);
2558
2559 dout("lease_release inode %p dentry %p mask %d to mds%d\n",
2560 inode, dentry, mask, session->s_mds);
2561 ceph_mdsc_lease_send_msg(session, inode, dentry,
2562 CEPH_MDS_LEASE_RELEASE, seq);
2563 ceph_put_mds_session(session);
2564}
2565
2566/*
2567 * drop all leases (and dentry refs) in preparation for umount
2568 */
2569static void drop_leases(struct ceph_mds_client *mdsc)
2570{
2571 int i;
2572
2573 dout("drop_leases\n");
2574 mutex_lock(&mdsc->mutex);
2575 for (i = 0; i < mdsc->max_sessions; i++) {
2576 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2577 if (!s)
2578 continue;
2579 mutex_unlock(&mdsc->mutex);
2580 mutex_lock(&s->s_mutex);
2581 mutex_unlock(&s->s_mutex);
2582 ceph_put_mds_session(s);
2583 mutex_lock(&mdsc->mutex);
2584 }
2585 mutex_unlock(&mdsc->mutex);
2586}
2587
2588
2589
2590/*
2591 * delayed work -- periodically trim expired leases, renew caps with mds
2592 */
2593static void schedule_delayed(struct ceph_mds_client *mdsc)
2594{
2595 int delay = 5;
2596 unsigned hz = round_jiffies_relative(HZ * delay);
2597 schedule_delayed_work(&mdsc->delayed_work, hz);
2598}
2599
2600static void delayed_work(struct work_struct *work)
2601{
2602 int i;
2603 struct ceph_mds_client *mdsc =
2604 container_of(work, struct ceph_mds_client, delayed_work.work);
2605 int renew_interval;
2606 int renew_caps;
2607
2608 dout("mdsc delayed_work\n");
afcdaea3 2609 ceph_check_delayed_caps(mdsc);
2f2dc053
SW		 2610
2611 mutex_lock(&mdsc->mutex);
2612 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
2613 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
2614 mdsc->last_renew_caps);
2615 if (renew_caps)
2616 mdsc->last_renew_caps = jiffies;
2617
2618 for (i = 0; i < mdsc->max_sessions; i++) {
2619 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2620 if (s == NULL)
2621 continue;
2622 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
2623 dout("resending session close request for mds%d\n",
2624 s->s_mds);
2625 request_close_session(mdsc, s);
2626 ceph_put_mds_session(s);
2627 continue;
2628 }
2629 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
2630 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
2631 s->s_state = CEPH_MDS_SESSION_HUNG;
2632 pr_info("mds%d hung\n", s->s_mds);
2633 }
2634 }
2635 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
2636 /* this mds is failed or recovering, just wait */
2637 ceph_put_mds_session(s);
2638 continue;
2639 }
2640 mutex_unlock(&mdsc->mutex);
2641
2642 mutex_lock(&s->s_mutex);
2643 if (renew_caps)
2644 send_renew_caps(mdsc, s);
2645 else
2646 ceph_con_keepalive(&s->s_con);
2647 add_cap_releases(mdsc, s, -1);
aab53dd9
SW		 2648 if (s->s_state == CEPH_MDS_SESSION_OPEN ||
2649 s->s_state == CEPH_MDS_SESSION_HUNG)
2650 send_cap_releases(mdsc, s);
2f2dc053
SW		 2651 mutex_unlock(&s->s_mutex);
2652 ceph_put_mds_session(s);
2653
2654 mutex_lock(&mdsc->mutex);
2655 }
2656 mutex_unlock(&mdsc->mutex);
2657
2658 schedule_delayed(mdsc);
2659}
2660
2661
5f44f142 2662int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
2f2dc053
SW		 2663{
2664 mdsc->client = client;
2665 mutex_init(&mdsc->mutex);
2666 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
2d06eeb8
CR		 2667 if (mdsc->mdsmap == NULL)
2668 return -ENOMEM;
2669
2f2dc053
SW		 2670 init_completion(&mdsc->safe_umount_waiters);
2671 init_completion(&mdsc->session_close_waiters);
2672 INIT_LIST_HEAD(&mdsc->waiting_for_map);
2673 mdsc->sessions = NULL;
2674 mdsc->max_sessions = 0;
2675 mdsc->stopping = 0;
2676 init_rwsem(&mdsc->snap_rwsem);
a105f00c 2677 mdsc->snap_realms = RB_ROOT;
2f2dc053
SW		 2678 INIT_LIST_HEAD(&mdsc->snap_empty);
2679 spin_lock_init(&mdsc->snap_empty_lock);
2680 mdsc->last_tid = 0;
44ca18f2 2681 mdsc->request_tree = RB_ROOT;
2f2dc053
SW		 2682 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
2683 mdsc->last_renew_caps = jiffies;
2684 INIT_LIST_HEAD(&mdsc->cap_delay_list);
2685 spin_lock_init(&mdsc->cap_delay_lock);
2686 INIT_LIST_HEAD(&mdsc->snap_flush_list);
2687 spin_lock_init(&mdsc->snap_flush_lock);
2688 mdsc->cap_flush_seq = 0;
2689 INIT_LIST_HEAD(&mdsc->cap_dirty);
2690 mdsc->num_cap_flushing = 0;
2691 spin_lock_init(&mdsc->cap_dirty_lock);
2692 init_waitqueue_head(&mdsc->cap_flushing_wq);
2693 spin_lock_init(&mdsc->dentry_lru_lock);
2694 INIT_LIST_HEAD(&mdsc->dentry_lru);
2d06eeb8 2695
5f44f142 2696 return 0;
2f2dc053
SW		 2697}
2698
2699/*
2700 * Wait for safe replies on open mds requests. If we time out, drop
2701 * all requests from the tree to avoid dangling dentry refs.
2702 */
2703static void wait_requests(struct ceph_mds_client *mdsc)
2704{
2705 struct ceph_mds_request *req;
2706 struct ceph_client *client = mdsc->client;
2707
2708 mutex_lock(&mdsc->mutex);
44ca18f2 2709 if (__get_oldest_req(mdsc)) {
2f2dc053 2710 mutex_unlock(&mdsc->mutex);
44ca18f2 2711
2f2dc053
SW		 2712 dout("wait_requests waiting for requests\n");
2713 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
6b805185 2714 client->mount_args->mount_timeout * HZ);
2f2dc053
SW		 2715
2716 /* tear down remaining requests */
44ca18f2
SW		 2717 mutex_lock(&mdsc->mutex);
2718 while ((req = __get_oldest_req(mdsc))) {
2f2dc053
SW		 2719 dout("wait_requests timed out on tid %llu\n",
2720 req->r_tid);
44ca18f2 2721 __unregister_request(mdsc, req);
2f2dc053
SW		 2722 }
2723 }
2724 mutex_unlock(&mdsc->mutex);
2725 dout("wait_requests done\n");
2726}
2727
2728/*
2729 * called before mount is ro, and before dentries are torn down.
2730 * (hmm, does this still race with new lookups?)
2731 */
2732void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
2733{
2734 dout("pre_umount\n");
2735 mdsc->stopping = 1;
2736
2737 drop_leases(mdsc);
afcdaea3 2738 ceph_flush_dirty_caps(mdsc);
2f2dc053
SW		 2739 wait_requests(mdsc);
2740}
2741
2742/*
2743 * wait for all write mds requests to flush.
2744 */
2745static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
2746{
80fc7314 2747 struct ceph_mds_request *req = NULL, *nextreq;
44ca18f2 2748 struct rb_node *n;
2f2dc053
SW		 2749
2750 mutex_lock(&mdsc->mutex);
2751 dout("wait_unsafe_requests want %lld\n", want_tid);
80fc7314 2752restart:
44ca18f2
SW		 2753 req = __get_oldest_req(mdsc);
2754 while (req && req->r_tid <= want_tid) {
80fc7314
SW		 2755 /* find next request */
2756 n = rb_next(&req->r_node);
2757 if (n)
2758 nextreq = rb_entry(n, struct ceph_mds_request, r_node);
2759 else
2760 nextreq = NULL;
44ca18f2
SW		 2761 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
2762 /* write op */
2763 ceph_mdsc_get_request(req);
80fc7314
SW		 2764 if (nextreq)
2765 ceph_mdsc_get_request(nextreq);
44ca18f2
SW		 2766 mutex_unlock(&mdsc->mutex);
2767 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
2768 req->r_tid, want_tid);
2769 wait_for_completion(&req->r_safe_completion);
2770 mutex_lock(&mdsc->mutex);
44ca18f2 2771 ceph_mdsc_put_request(req);
80fc7314
SW		 2772 if (!nextreq)
2773 break; /* next dne before, so we're done! */
2774 if (RB_EMPTY_NODE(&nextreq->r_node)) {
2775 /* next request was removed from tree */
2776 ceph_mdsc_put_request(nextreq);
2777 goto restart;
2778 }
2779 ceph_mdsc_put_request(nextreq); /* won't go away */
44ca18f2 2780 }
80fc7314 2781 req = nextreq;
2f2dc053
SW		 2782 }
2783 mutex_unlock(&mdsc->mutex);
2784 dout("wait_unsafe_requests done\n");
2785}
2786
2787void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
2788{
2789 u64 want_tid, want_flush;
2790
56b7cf95
SW		 2791 if (mdsc->client->mount_state == CEPH_MOUNT_SHUTDOWN)
2792 return;
2793
2f2dc053
SW		 2794 dout("sync\n");
2795 mutex_lock(&mdsc->mutex);
2796 want_tid = mdsc->last_tid;
2797 want_flush = mdsc->cap_flush_seq;
2798 mutex_unlock(&mdsc->mutex);
2799 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
2800
afcdaea3 2801 ceph_flush_dirty_caps(mdsc);
2f2dc053
SW		 2802
2803 wait_unsafe_requests(mdsc, want_tid);
2804 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
2805}
2806
2807
2808/*
2809 * called after sb is ro.
2810 */
2811void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
2812{
2813 struct ceph_mds_session *session;
2814 int i;
2815 int n;
2816 struct ceph_client *client = mdsc->client;
6b805185 2817 unsigned long started, timeout = client->mount_args->mount_timeout * HZ;
2f2dc053
SW		 2818
2819 dout("close_sessions\n");
2820
2821 mutex_lock(&mdsc->mutex);
2822
2823 /* close sessions */
2824 started = jiffies;
2825 while (time_before(jiffies, started + timeout)) {
2826 dout("closing sessions\n");
2827 n = 0;
2828 for (i = 0; i < mdsc->max_sessions; i++) {
2829 session = __ceph_lookup_mds_session(mdsc, i);
2830 if (!session)
2831 continue;
2832 mutex_unlock(&mdsc->mutex);
2833 mutex_lock(&session->s_mutex);
2834 __close_session(mdsc, session);
2835 mutex_unlock(&session->s_mutex);
2836 ceph_put_mds_session(session);
2837 mutex_lock(&mdsc->mutex);
2838 n++;
2839 }
2840 if (n == 0)
2841 break;
2842
2843 if (client->mount_state == CEPH_MOUNT_SHUTDOWN)
2844 break;
2845
2846 dout("waiting for sessions to close\n");
2847 mutex_unlock(&mdsc->mutex);
2848 wait_for_completion_timeout(&mdsc->session_close_waiters,
2849 timeout);
2850 mutex_lock(&mdsc->mutex);
2851 }
2852
2853 /* tear down remaining sessions */
2854 for (i = 0; i < mdsc->max_sessions; i++) {
2855 if (mdsc->sessions[i]) {
2856 session = get_session(mdsc->sessions[i]);
2600d2dd 2857 __unregister_session(mdsc, session);
2f2dc053
SW		 2858 mutex_unlock(&mdsc->mutex);
2859 mutex_lock(&session->s_mutex);
2860 remove_session_caps(session);
2861 mutex_unlock(&session->s_mutex);
2862 ceph_put_mds_session(session);
2863 mutex_lock(&mdsc->mutex);
2864 }
2865 }
2866
2867 WARN_ON(!list_empty(&mdsc->cap_delay_list));
2868
2869 mutex_unlock(&mdsc->mutex);
2870
2871 ceph_cleanup_empty_realms(mdsc);
2872
2873 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
2874
2875 dout("stopped\n");
2876}
2877
2878void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
2879{
2880 dout("stop\n");
2881 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
2882 if (mdsc->mdsmap)
2883 ceph_mdsmap_destroy(mdsc->mdsmap);
2884 kfree(mdsc->sessions);
2885}
2886
2887
2888/*
2889 * handle mds map update.
2890 */
2891void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
2892{
2893 u32 epoch;
2894 u32 maplen;
2895 void *p = msg->front.iov_base;
2896 void *end = p + msg->front.iov_len;
2897 struct ceph_mdsmap *newmap, *oldmap;
2898 struct ceph_fsid fsid;
2899 int err = -EINVAL;
2900
2901 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
2902 ceph_decode_copy(&p, &fsid, sizeof(fsid));
0743304d
SW		 2903 if (ceph_check_fsid(mdsc->client, &fsid) < 0)
2904 return;
c89136ea
SW		 2905 epoch = ceph_decode_32(&p);
2906 maplen = ceph_decode_32(&p);
2f2dc053
SW		 2907 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
2908
2909 /* do we need it? */
2910 ceph_monc_got_mdsmap(&mdsc->client->monc, epoch);
2911 mutex_lock(&mdsc->mutex);
2912 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
2913 dout("handle_map epoch %u <= our %u\n",
2914 epoch, mdsc->mdsmap->m_epoch);
2915 mutex_unlock(&mdsc->mutex);
2916 return;
2917 }
2918
2919 newmap = ceph_mdsmap_decode(&p, end);
2920 if (IS_ERR(newmap)) {
2921 err = PTR_ERR(newmap);
2922 goto bad_unlock;
2923 }
2924
2925 /* swap into place */
2926 if (mdsc->mdsmap) {
2927 oldmap = mdsc->mdsmap;
2928 mdsc->mdsmap = newmap;
2929 check_new_map(mdsc, newmap, oldmap);
2930 ceph_mdsmap_destroy(oldmap);
2931 } else {
2932 mdsc->mdsmap = newmap; /* first mds map */
2933 }
2934 mdsc->client->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
2935
2936 __wake_requests(mdsc, &mdsc->waiting_for_map);
2937
2938 mutex_unlock(&mdsc->mutex);
2939 schedule_delayed(mdsc);
2940 return;
2941
2942bad_unlock:
2943 mutex_unlock(&mdsc->mutex);
2944bad:
2945 pr_err("error decoding mdsmap %d\n", err);
2946 return;
2947}
2948
2949static struct ceph_connection *con_get(struct ceph_connection *con)
2950{
2951 struct ceph_mds_session *s = con->private;
2952
2953 if (get_session(s)) {
2600d2dd 2954 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
2f2dc053
SW		 2955 return con;
2956 }
2957 dout("mdsc con_get %p FAIL\n", s);
2958 return NULL;
2959}
2960
2961static void con_put(struct ceph_connection *con)
2962{
2963 struct ceph_mds_session *s = con->private;
2964
2f2dc053 2965 ceph_put_mds_session(s);
2600d2dd 2966 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref));
2f2dc053
SW		 2967}
2968
2969/*
2970 * if the client is unresponsive for long enough, the mds will kill
2971 * the session entirely.
2972 */
2973static void peer_reset(struct ceph_connection *con)
2974{
2975 struct ceph_mds_session *s = con->private;
2976
2977 pr_err("mds%d gave us the boot. IMPLEMENT RECONNECT.\n",
2978 s->s_mds);
2979}
2980
2981static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
2982{
2983 struct ceph_mds_session *s = con->private;
2984 struct ceph_mds_client *mdsc = s->s_mdsc;
2985 int type = le16_to_cpu(msg->hdr.type);
2986
2600d2dd
SW		 2987 mutex_lock(&mdsc->mutex);
2988 if (__verify_registered_session(mdsc, s) < 0) {
2989 mutex_unlock(&mdsc->mutex);
2990 goto out;
2991 }
2992 mutex_unlock(&mdsc->mutex);
2993
2f2dc053
SW		 2994 switch (type) {
2995 case CEPH_MSG_MDS_MAP:
2996 ceph_mdsc_handle_map(mdsc, msg);
2997 break;
2998 case CEPH_MSG_CLIENT_SESSION:
2999 handle_session(s, msg);
3000 break;
3001 case CEPH_MSG_CLIENT_REPLY:
3002 handle_reply(s, msg);
3003 break;
3004 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
2600d2dd 3005 handle_forward(mdsc, s, msg);
2f2dc053
SW		 3006 break;
3007 case CEPH_MSG_CLIENT_CAPS:
3008 ceph_handle_caps(s, msg);
3009 break;
3010 case CEPH_MSG_CLIENT_SNAP:
2600d2dd 3011 ceph_handle_snap(mdsc, s, msg);
2f2dc053
SW		 3012 break;
3013 case CEPH_MSG_CLIENT_LEASE:
2600d2dd 3014 handle_lease(mdsc, s, msg);
2f2dc053
SW		 3015 break;
3016
3017 default:
3018 pr_err("received unknown message type %d %s\n", type,
3019 ceph_msg_type_name(type));
3020 }
2600d2dd 3021out:
2f2dc053
SW		 3022 ceph_msg_put(msg);
3023}
3024
4e7a5dcd
SW		 3025/*
3026 * authentication
3027 */
3028static int get_authorizer(struct ceph_connection *con,
3029 void **buf, int *len, int *proto,
3030 void **reply_buf, int *reply_len, int force_new)
3031{
3032 struct ceph_mds_session *s = con->private;
3033 struct ceph_mds_client *mdsc = s->s_mdsc;
3034 struct ceph_auth_client *ac = mdsc->client->monc.auth;
3035 int ret = 0;
3036
3037 if (force_new && s->s_authorizer) {
3038 ac->ops->destroy_authorizer(ac, s->s_authorizer);
3039 s->s_authorizer = NULL;
3040 }
3041 if (s->s_authorizer == NULL) {
3042 if (ac->ops->create_authorizer) {
3043 ret = ac->ops->create_authorizer(
3044 ac, CEPH_ENTITY_TYPE_MDS,
3045 &s->s_authorizer,
3046 &s->s_authorizer_buf,
3047 &s->s_authorizer_buf_len,
3048 &s->s_authorizer_reply_buf,
3049 &s->s_authorizer_reply_buf_len);
3050 if (ret)
3051 return ret;
3052 }
3053 }
3054
3055 *proto = ac->protocol;
3056 *buf = s->s_authorizer_buf;
3057 *len = s->s_authorizer_buf_len;
3058 *reply_buf = s->s_authorizer_reply_buf;
3059 *reply_len = s->s_authorizer_reply_buf_len;
3060 return 0;
3061}
3062
3063
3064static int verify_authorizer_reply(struct ceph_connection *con, int len)
3065{
3066 struct ceph_mds_session *s = con->private;
3067 struct ceph_mds_client *mdsc = s->s_mdsc;
3068 struct ceph_auth_client *ac = mdsc->client->monc.auth;
3069
3070 return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
3071}
3072
9bd2e6f8
SW		 3073static int invalidate_authorizer(struct ceph_connection *con)
3074{
3075 struct ceph_mds_session *s = con->private;
3076 struct ceph_mds_client *mdsc = s->s_mdsc;
3077 struct ceph_auth_client *ac = mdsc->client->monc.auth;
3078
3079 if (ac->ops->invalidate_authorizer)
3080 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3081
3082 return ceph_monc_validate_auth(&mdsc->client->monc);
3083}
3084
2f2dc053
SW		 3085const static struct ceph_connection_operations mds_con_ops = {
3086 .get = con_get,
3087 .put = con_put,
3088 .dispatch = dispatch,
4e7a5dcd
SW		 3089 .get_authorizer = get_authorizer,
3090 .verify_authorizer_reply = verify_authorizer_reply,
9bd2e6f8 3091 .invalidate_authorizer = invalidate_authorizer,
2f2dc053 3092 .peer_reset = peer_reset,
2f2dc053
SW		 3093};
3094
3095
3096
3097
3098/* eof */
Linux kernel - Deliverables
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