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-rw-r--r--fs/ceph/mds_client.c3021
1 files changed, 3021 insertions, 0 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
new file mode 100644
index 000000000000..a2600101ec22
--- /dev/null
+++ b/fs/ceph/mds_client.c
@@ -0,0 +1,3021 @@
1#include "ceph_debug.h"
2
3#include <linux/wait.h>
4#include <linux/sched.h>
5
6#include "mds_client.h"
7#include "mon_client.h"
8#include "super.h"
9#include "messenger.h"
10#include "decode.h"
11#include "auth.h"
12#include "pagelist.h"
13
14/*
15 * A cluster of MDS (metadata server) daemons is responsible for
16 * managing the file system namespace (the directory hierarchy and
17 * inodes) and for coordinating shared access to storage. Metadata is
18 * partitioning hierarchically across a number of servers, and that
19 * partition varies over time as the cluster adjusts the distribution
20 * in order to balance load.
21 *
22 * The MDS client is primarily responsible to managing synchronous
23 * metadata requests for operations like open, unlink, and so forth.
24 * If there is a MDS failure, we find out about it when we (possibly
25 * request and) receive a new MDS map, and can resubmit affected
26 * requests.
27 *
28 * For the most part, though, we take advantage of a lossless
29 * communications channel to the MDS, and do not need to worry about
30 * timing out or resubmitting requests.
31 *
32 * We maintain a stateful "session" with each MDS we interact with.
33 * Within each session, we sent periodic heartbeat messages to ensure
34 * any capabilities or leases we have been issues remain valid. If
35 * the session times out and goes stale, our leases and capabilities
36 * are no longer valid.
37 */
38
39static void __wake_requests(struct ceph_mds_client *mdsc,
40 struct list_head *head);
41
42const static struct ceph_connection_operations mds_con_ops;
43
44
45/*
46 * mds reply parsing
47 */
48
49/*
50 * parse individual inode info
51 */
52static int parse_reply_info_in(void **p, void *end,
53 struct ceph_mds_reply_info_in *info)
54{
55 int err = -EIO;
56
57 info->in = *p;
58 *p += sizeof(struct ceph_mds_reply_inode) +
59 sizeof(*info->in->fragtree.splits) *
60 le32_to_cpu(info->in->fragtree.nsplits);
61
62 ceph_decode_32_safe(p, end, info->symlink_len, bad);
63 ceph_decode_need(p, end, info->symlink_len, bad);
64 info->symlink = *p;
65 *p += info->symlink_len;
66
67 ceph_decode_32_safe(p, end, info->xattr_len, bad);
68 ceph_decode_need(p, end, info->xattr_len, bad);
69 info->xattr_data = *p;
70 *p += info->xattr_len;
71 return 0;
72bad:
73 return err;
74}
75
76/*
77 * parse a normal reply, which may contain a (dir+)dentry and/or a
78 * target inode.
79 */
80static int parse_reply_info_trace(void **p, void *end,
81 struct ceph_mds_reply_info_parsed *info)
82{
83 int err;
84
85 if (info->head->is_dentry) {
86 err = parse_reply_info_in(p, end, &info->diri);
87 if (err < 0)
88 goto out_bad;
89
90 if (unlikely(*p + sizeof(*info->dirfrag) > end))
91 goto bad;
92 info->dirfrag = *p;
93 *p += sizeof(*info->dirfrag) +
94 sizeof(u32)*le32_to_cpu(info->dirfrag->ndist);
95 if (unlikely(*p > end))
96 goto bad;
97
98 ceph_decode_32_safe(p, end, info->dname_len, bad);
99 ceph_decode_need(p, end, info->dname_len, bad);
100 info->dname = *p;
101 *p += info->dname_len;
102 info->dlease = *p;
103 *p += sizeof(*info->dlease);
104 }
105
106 if (info->head->is_target) {
107 err = parse_reply_info_in(p, end, &info->targeti);
108 if (err < 0)
109 goto out_bad;
110 }
111
112 if (unlikely(*p != end))
113 goto bad;
114 return 0;
115
116bad:
117 err = -EIO;
118out_bad:
119 pr_err("problem parsing mds trace %d\n", err);
120 return err;
121}
122
123/*
124 * parse readdir results
125 */
126static int parse_reply_info_dir(void **p, void *end,
127 struct ceph_mds_reply_info_parsed *info)
128{
129 u32 num, i = 0;
130 int err;
131
132 info->dir_dir = *p;
133 if (*p + sizeof(*info->dir_dir) > end)
134 goto bad;
135 *p += sizeof(*info->dir_dir) +
136 sizeof(u32)*le32_to_cpu(info->dir_dir->ndist);
137 if (*p > end)
138 goto bad;
139
140 ceph_decode_need(p, end, sizeof(num) + 2, bad);
141 num = ceph_decode_32(p);
142 info->dir_end = ceph_decode_8(p);
143 info->dir_complete = ceph_decode_8(p);
144 if (num == 0)
145 goto done;
146
147 /* alloc large array */
148 info->dir_nr = num;
149 info->dir_in = kcalloc(num, sizeof(*info->dir_in) +
150 sizeof(*info->dir_dname) +
151 sizeof(*info->dir_dname_len) +
152 sizeof(*info->dir_dlease),
153 GFP_NOFS);
154 if (info->dir_in == NULL) {
155 err = -ENOMEM;
156 goto out_bad;
157 }
158 info->dir_dname = (void *)(info->dir_in + num);
159 info->dir_dname_len = (void *)(info->dir_dname + num);
160 info->dir_dlease = (void *)(info->dir_dname_len + num);
161
162 while (num) {
163 /* dentry */
164 ceph_decode_need(p, end, sizeof(u32)*2, bad);
165 info->dir_dname_len[i] = ceph_decode_32(p);
166 ceph_decode_need(p, end, info->dir_dname_len[i], bad);
167 info->dir_dname[i] = *p;
168 *p += info->dir_dname_len[i];
169 dout("parsed dir dname '%.*s'\n", info->dir_dname_len[i],
170 info->dir_dname[i]);
171 info->dir_dlease[i] = *p;
172 *p += sizeof(struct ceph_mds_reply_lease);
173
174 /* inode */
175 err = parse_reply_info_in(p, end, &info->dir_in[i]);
176 if (err < 0)
177 goto out_bad;
178 i++;
179 num--;
180 }
181
182done:
183 if (*p != end)
184 goto bad;
185 return 0;
186
187bad:
188 err = -EIO;
189out_bad:
190 pr_err("problem parsing dir contents %d\n", err);
191 return err;
192}
193
194/*
195 * parse entire mds reply
196 */
197static int parse_reply_info(struct ceph_msg *msg,
198 struct ceph_mds_reply_info_parsed *info)
199{
200 void *p, *end;
201 u32 len;
202 int err;
203
204 info->head = msg->front.iov_base;
205 p = msg->front.iov_base + sizeof(struct ceph_mds_reply_head);
206 end = p + msg->front.iov_len - sizeof(struct ceph_mds_reply_head);
207
208 /* trace */
209 ceph_decode_32_safe(&p, end, len, bad);
210 if (len > 0) {
211 err = parse_reply_info_trace(&p, p+len, info);
212 if (err < 0)
213 goto out_bad;
214 }
215
216 /* dir content */
217 ceph_decode_32_safe(&p, end, len, bad);
218 if (len > 0) {
219 err = parse_reply_info_dir(&p, p+len, info);
220 if (err < 0)
221 goto out_bad;
222 }
223
224 /* snap blob */
225 ceph_decode_32_safe(&p, end, len, bad);
226 info->snapblob_len = len;
227 info->snapblob = p;
228 p += len;
229
230 if (p != end)
231 goto bad;
232 return 0;
233
234bad:
235 err = -EIO;
236out_bad:
237 pr_err("mds parse_reply err %d\n", err);
238 return err;
239}
240
241static void destroy_reply_info(struct ceph_mds_reply_info_parsed *info)
242{
243 kfree(info->dir_in);
244}
245
246
247/*
248 * sessions
249 */
250static const char *session_state_name(int s)
251{
252 switch (s) {
253 case CEPH_MDS_SESSION_NEW: return "new";
254 case CEPH_MDS_SESSION_OPENING: return "opening";
255 case CEPH_MDS_SESSION_OPEN: return "open";
256 case CEPH_MDS_SESSION_HUNG: return "hung";
257 case CEPH_MDS_SESSION_CLOSING: return "closing";
258 case CEPH_MDS_SESSION_RESTARTING: return "restarting";
259 case CEPH_MDS_SESSION_RECONNECTING: return "reconnecting";
260 default: return "???";
261 }
262}
263
264static struct ceph_mds_session *get_session(struct ceph_mds_session *s)
265{
266 if (atomic_inc_not_zero(&s->s_ref)) {
267 dout("mdsc get_session %p %d -> %d\n", s,
268 atomic_read(&s->s_ref)-1, atomic_read(&s->s_ref));
269 return s;
270 } else {
271 dout("mdsc get_session %p 0 -- FAIL", s);
272 return NULL;
273 }
274}
275
276void ceph_put_mds_session(struct ceph_mds_session *s)
277{
278 dout("mdsc put_session %p %d -> %d\n", s,
279 atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
280 if (atomic_dec_and_test(&s->s_ref)) {
281 if (s->s_authorizer)
282 s->s_mdsc->client->monc.auth->ops->destroy_authorizer(
283 s->s_mdsc->client->monc.auth, s->s_authorizer);
284 kfree(s);
285 }
286}
287
288/*
289 * called under mdsc->mutex
290 */
291struct ceph_mds_session *__ceph_lookup_mds_session(struct ceph_mds_client *mdsc,
292 int mds)
293{
294 struct ceph_mds_session *session;
295
296 if (mds >= mdsc->max_sessions || mdsc->sessions[mds] == NULL)
297 return NULL;
298 session = mdsc->sessions[mds];
299 dout("lookup_mds_session %p %d\n", session,
300 atomic_read(&session->s_ref));
301 get_session(session);
302 return session;
303}
304
305static bool __have_session(struct ceph_mds_client *mdsc, int mds)
306{
307 if (mds >= mdsc->max_sessions)
308 return false;
309 return mdsc->sessions[mds];
310}
311
312static int __verify_registered_session(struct ceph_mds_client *mdsc,
313 struct ceph_mds_session *s)
314{
315 if (s->s_mds >= mdsc->max_sessions ||
316 mdsc->sessions[s->s_mds] != s)
317 return -ENOENT;
318 return 0;
319}
320
321/*
322 * create+register a new session for given mds.
323 * called under mdsc->mutex.
324 */
325static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc,
326 int mds)
327{
328 struct ceph_mds_session *s;
329
330 s = kzalloc(sizeof(*s), GFP_NOFS);
331 s->s_mdsc = mdsc;
332 s->s_mds = mds;
333 s->s_state = CEPH_MDS_SESSION_NEW;
334 s->s_ttl = 0;
335 s->s_seq = 0;
336 mutex_init(&s->s_mutex);
337
338 ceph_con_init(mdsc->client->msgr, &s->s_con);
339 s->s_con.private = s;
340 s->s_con.ops = &mds_con_ops;
341 s->s_con.peer_name.type = CEPH_ENTITY_TYPE_MDS;
342 s->s_con.peer_name.num = cpu_to_le64(mds);
343
344 spin_lock_init(&s->s_cap_lock);
345 s->s_cap_gen = 0;
346 s->s_cap_ttl = 0;
347 s->s_renew_requested = 0;
348 s->s_renew_seq = 0;
349 INIT_LIST_HEAD(&s->s_caps);
350 s->s_nr_caps = 0;
351 s->s_trim_caps = 0;
352 atomic_set(&s->s_ref, 1);
353 INIT_LIST_HEAD(&s->s_waiting);
354 INIT_LIST_HEAD(&s->s_unsafe);
355 s->s_num_cap_releases = 0;
356 s->s_cap_iterator = NULL;
357 INIT_LIST_HEAD(&s->s_cap_releases);
358 INIT_LIST_HEAD(&s->s_cap_releases_done);
359 INIT_LIST_HEAD(&s->s_cap_flushing);
360 INIT_LIST_HEAD(&s->s_cap_snaps_flushing);
361
362 dout("register_session mds%d\n", mds);
363 if (mds >= mdsc->max_sessions) {
364 int newmax = 1 << get_count_order(mds+1);
365 struct ceph_mds_session **sa;
366
367 dout("register_session realloc to %d\n", newmax);
368 sa = kcalloc(newmax, sizeof(void *), GFP_NOFS);
369 if (sa == NULL)
370 goto fail_realloc;
371 if (mdsc->sessions) {
372 memcpy(sa, mdsc->sessions,
373 mdsc->max_sessions * sizeof(void *));
374 kfree(mdsc->sessions);
375 }
376 mdsc->sessions = sa;
377 mdsc->max_sessions = newmax;
378 }
379 mdsc->sessions[mds] = s;
380 atomic_inc(&s->s_ref); /* one ref to sessions[], one to caller */
381
382 ceph_con_open(&s->s_con, ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
383
384 return s;
385
386fail_realloc:
387 kfree(s);
388 return ERR_PTR(-ENOMEM);
389}
390
391/*
392 * called under mdsc->mutex
393 */
394static void __unregister_session(struct ceph_mds_client *mdsc,
395 struct ceph_mds_session *s)
396{
397 dout("__unregister_session mds%d %p\n", s->s_mds, s);
398 BUG_ON(mdsc->sessions[s->s_mds] != s);
399 mdsc->sessions[s->s_mds] = NULL;
400 ceph_con_close(&s->s_con);
401 ceph_put_mds_session(s);
402}
403
404/*
405 * drop session refs in request.
406 *
407 * should be last request ref, or hold mdsc->mutex
408 */
409static void put_request_session(struct ceph_mds_request *req)
410{
411 if (req->r_session) {
412 ceph_put_mds_session(req->r_session);
413 req->r_session = NULL;
414 }
415}
416
417void ceph_mdsc_release_request(struct kref *kref)
418{
419 struct ceph_mds_request *req = container_of(kref,
420 struct ceph_mds_request,
421 r_kref);
422 if (req->r_request)
423 ceph_msg_put(req->r_request);
424 if (req->r_reply) {
425 ceph_msg_put(req->r_reply);
426 destroy_reply_info(&req->r_reply_info);
427 }
428 if (req->r_inode) {
429 ceph_put_cap_refs(ceph_inode(req->r_inode),
430 CEPH_CAP_PIN);
431 iput(req->r_inode);
432 }
433 if (req->r_locked_dir)
434 ceph_put_cap_refs(ceph_inode(req->r_locked_dir),
435 CEPH_CAP_PIN);
436 if (req->r_target_inode)
437 iput(req->r_target_inode);
438 if (req->r_dentry)
439 dput(req->r_dentry);
440 if (req->r_old_dentry) {
441 ceph_put_cap_refs(
442 ceph_inode(req->r_old_dentry->d_parent->d_inode),
443 CEPH_CAP_PIN);
444 dput(req->r_old_dentry);
445 }
446 kfree(req->r_path1);
447 kfree(req->r_path2);
448 put_request_session(req);
449 ceph_unreserve_caps(&req->r_caps_reservation);
450 kfree(req);
451}
452
453/*
454 * lookup session, bump ref if found.
455 *
456 * called under mdsc->mutex.
457 */
458static struct ceph_mds_request *__lookup_request(struct ceph_mds_client *mdsc,
459 u64 tid)
460{
461 struct ceph_mds_request *req;
462 struct rb_node *n = mdsc->request_tree.rb_node;
463
464 while (n) {
465 req = rb_entry(n, struct ceph_mds_request, r_node);
466 if (tid < req->r_tid)
467 n = n->rb_left;
468 else if (tid > req->r_tid)
469 n = n->rb_right;
470 else {
471 ceph_mdsc_get_request(req);
472 return req;
473 }
474 }
475 return NULL;
476}
477
478static void __insert_request(struct ceph_mds_client *mdsc,
479 struct ceph_mds_request *new)
480{
481 struct rb_node **p = &mdsc->request_tree.rb_node;
482 struct rb_node *parent = NULL;
483 struct ceph_mds_request *req = NULL;
484
485 while (*p) {
486 parent = *p;
487 req = rb_entry(parent, struct ceph_mds_request, r_node);
488 if (new->r_tid < req->r_tid)
489 p = &(*p)->rb_left;
490 else if (new->r_tid > req->r_tid)
491 p = &(*p)->rb_right;
492 else
493 BUG();
494 }
495
496 rb_link_node(&new->r_node, parent, p);
497 rb_insert_color(&new->r_node, &mdsc->request_tree);
498}
499
500/*
501 * Register an in-flight request, and assign a tid. Link to directory
502 * are modifying (if any).
503 *
504 * Called under mdsc->mutex.
505 */
506static void __register_request(struct ceph_mds_client *mdsc,
507 struct ceph_mds_request *req,
508 struct inode *dir)
509{
510 req->r_tid = ++mdsc->last_tid;
511 if (req->r_num_caps)
512 ceph_reserve_caps(&req->r_caps_reservation, req->r_num_caps);
513 dout("__register_request %p tid %lld\n", req, req->r_tid);
514 ceph_mdsc_get_request(req);
515 __insert_request(mdsc, req);
516
517 if (dir) {
518 struct ceph_inode_info *ci = ceph_inode(dir);
519
520 spin_lock(&ci->i_unsafe_lock);
521 req->r_unsafe_dir = dir;
522 list_add_tail(&req->r_unsafe_dir_item, &ci->i_unsafe_dirops);
523 spin_unlock(&ci->i_unsafe_lock);
524 }
525}
526
527static void __unregister_request(struct ceph_mds_client *mdsc,
528 struct ceph_mds_request *req)
529{
530 dout("__unregister_request %p tid %lld\n", req, req->r_tid);
531 rb_erase(&req->r_node, &mdsc->request_tree);
532 ceph_mdsc_put_request(req);
533
534 if (req->r_unsafe_dir) {
535 struct ceph_inode_info *ci = ceph_inode(req->r_unsafe_dir);
536
537 spin_lock(&ci->i_unsafe_lock);
538 list_del_init(&req->r_unsafe_dir_item);
539 spin_unlock(&ci->i_unsafe_lock);
540 }
541}
542
543/*
544 * Choose mds to send request to next. If there is a hint set in the
545 * request (e.g., due to a prior forward hint from the mds), use that.
546 * Otherwise, consult frag tree and/or caps to identify the
547 * appropriate mds. If all else fails, choose randomly.
548 *
549 * Called under mdsc->mutex.
550 */
551static int __choose_mds(struct ceph_mds_client *mdsc,
552 struct ceph_mds_request *req)
553{
554 struct inode *inode;
555 struct ceph_inode_info *ci;
556 struct ceph_cap *cap;
557 int mode = req->r_direct_mode;
558 int mds = -1;
559 u32 hash = req->r_direct_hash;
560 bool is_hash = req->r_direct_is_hash;
561
562 /*
563 * is there a specific mds we should try? ignore hint if we have
564 * no session and the mds is not up (active or recovering).
565 */
566 if (req->r_resend_mds >= 0 &&
567 (__have_session(mdsc, req->r_resend_mds) ||
568 ceph_mdsmap_get_state(mdsc->mdsmap, req->r_resend_mds) > 0)) {
569 dout("choose_mds using resend_mds mds%d\n",
570 req->r_resend_mds);
571 return req->r_resend_mds;
572 }
573
574 if (mode == USE_RANDOM_MDS)
575 goto random;
576
577 inode = NULL;
578 if (req->r_inode) {
579 inode = req->r_inode;
580 } else if (req->r_dentry) {
581 if (req->r_dentry->d_inode) {
582 inode = req->r_dentry->d_inode;
583 } else {
584 inode = req->r_dentry->d_parent->d_inode;
585 hash = req->r_dentry->d_name.hash;
586 is_hash = true;
587 }
588 }
589 dout("__choose_mds %p is_hash=%d (%d) mode %d\n", inode, (int)is_hash,
590 (int)hash, mode);
591 if (!inode)
592 goto random;
593 ci = ceph_inode(inode);
594
595 if (is_hash && S_ISDIR(inode->i_mode)) {
596 struct ceph_inode_frag frag;
597 int found;
598
599 ceph_choose_frag(ci, hash, &frag, &found);
600 if (found) {
601 if (mode == USE_ANY_MDS && frag.ndist > 0) {
602 u8 r;
603
604 /* choose a random replica */
605 get_random_bytes(&r, 1);
606 r %= frag.ndist;
607 mds = frag.dist[r];
608 dout("choose_mds %p %llx.%llx "
609 "frag %u mds%d (%d/%d)\n",
610 inode, ceph_vinop(inode),
611 frag.frag, frag.mds,
612 (int)r, frag.ndist);
613 return mds;
614 }
615
616 /* since this file/dir wasn't known to be
617 * replicated, then we want to look for the
618 * authoritative mds. */
619 mode = USE_AUTH_MDS;
620 if (frag.mds >= 0) {
621 /* choose auth mds */
622 mds = frag.mds;
623 dout("choose_mds %p %llx.%llx "
624 "frag %u mds%d (auth)\n",
625 inode, ceph_vinop(inode), frag.frag, mds);
626 return mds;
627 }
628 }
629 }
630
631 spin_lock(&inode->i_lock);
632 cap = NULL;
633 if (mode == USE_AUTH_MDS)
634 cap = ci->i_auth_cap;
635 if (!cap && !RB_EMPTY_ROOT(&ci->i_caps))
636 cap = rb_entry(rb_first(&ci->i_caps), struct ceph_cap, ci_node);
637 if (!cap) {
638 spin_unlock(&inode->i_lock);
639 goto random;
640 }
641 mds = cap->session->s_mds;
642 dout("choose_mds %p %llx.%llx mds%d (%scap %p)\n",
643 inode, ceph_vinop(inode), mds,
644 cap == ci->i_auth_cap ? "auth " : "", cap);
645 spin_unlock(&inode->i_lock);
646 return mds;
647
648random:
649 mds = ceph_mdsmap_get_random_mds(mdsc->mdsmap);
650 dout("choose_mds chose random mds%d\n", mds);
651 return mds;
652}
653
654
655/*
656 * session messages
657 */
658static struct ceph_msg *create_session_msg(u32 op, u64 seq)
659{
660 struct ceph_msg *msg;
661 struct ceph_mds_session_head *h;
662
663 msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h), 0, 0, NULL);
664 if (IS_ERR(msg)) {
665 pr_err("create_session_msg ENOMEM creating msg\n");
666 return ERR_PTR(PTR_ERR(msg));
667 }
668 h = msg->front.iov_base;
669 h->op = cpu_to_le32(op);
670 h->seq = cpu_to_le64(seq);
671 return msg;
672}
673
674/*
675 * send session open request.
676 *
677 * called under mdsc->mutex
678 */
679static int __open_session(struct ceph_mds_client *mdsc,
680 struct ceph_mds_session *session)
681{
682 struct ceph_msg *msg;
683 int mstate;
684 int mds = session->s_mds;
685 int err = 0;
686
687 /* wait for mds to go active? */
688 mstate = ceph_mdsmap_get_state(mdsc->mdsmap, mds);
689 dout("open_session to mds%d (%s)\n", mds,
690 ceph_mds_state_name(mstate));
691 session->s_state = CEPH_MDS_SESSION_OPENING;
692 session->s_renew_requested = jiffies;
693
694 /* send connect message */
695 msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq);
696 if (IS_ERR(msg)) {
697 err = PTR_ERR(msg);
698 goto out;
699 }
700 ceph_con_send(&session->s_con, msg);
701
702out:
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/*
734 * Helper to safely iterate over all caps associated with a session.
735 *
736 * caller must hold session s_mutex
737 */
738static int iterate_session_caps(struct ceph_mds_session *session,
739 int (*cb)(struct inode *, struct ceph_cap *,
740 void *), void *arg)
741{
742 struct list_head *p;
743 struct ceph_cap *cap;
744 struct inode *inode, *last_inode = NULL;
745 struct ceph_cap *old_cap = NULL;
746 int ret;
747
748 dout("iterate_session_caps %p mds%d\n", session, session->s_mds);
749 spin_lock(&session->s_cap_lock);
750 p = session->s_caps.next;
751 while (p != &session->s_caps) {
752 cap = list_entry(p, struct ceph_cap, session_caps);
753 inode = igrab(&cap->ci->vfs_inode);
754 if (!inode) {
755 p = p->next;
756 continue;
757 }
758 session->s_cap_iterator = cap;
759 spin_unlock(&session->s_cap_lock);
760
761 if (last_inode) {
762 iput(last_inode);
763 last_inode = NULL;
764 }
765 if (old_cap) {
766 ceph_put_cap(old_cap);
767 old_cap = NULL;
768 }
769
770 ret = cb(inode, cap, arg);
771 last_inode = inode;
772
773 spin_lock(&session->s_cap_lock);
774 p = p->next;
775 if (cap->ci == NULL) {
776 dout("iterate_session_caps finishing cap %p removal\n",
777 cap);
778 BUG_ON(cap->session != session);
779 list_del_init(&cap->session_caps);
780 session->s_nr_caps--;
781 cap->session = NULL;
782 old_cap = cap; /* put_cap it w/o locks held */
783 }
784 if (ret < 0)
785 goto out;
786 }
787 ret = 0;
788out:
789 session->s_cap_iterator = NULL;
790 spin_unlock(&session->s_cap_lock);
791
792 if (last_inode)
793 iput(last_inode);
794 if (old_cap)
795 ceph_put_cap(old_cap);
796
797 return ret;
798}
799
800static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
801 void *arg)
802{
803 struct ceph_inode_info *ci = ceph_inode(inode);
804 dout("removing cap %p, ci is %p, inode is %p\n",
805 cap, ci, &ci->vfs_inode);
806 ceph_remove_cap(cap);
807 return 0;
808}
809
810/*
811 * caller must hold session s_mutex
812 */
813static void remove_session_caps(struct ceph_mds_session *session)
814{
815 dout("remove_session_caps on %p\n", session);
816 iterate_session_caps(session, remove_session_caps_cb, NULL);
817 BUG_ON(session->s_nr_caps > 0);
818 cleanup_cap_releases(session);
819}
820
821/*
822 * wake up any threads waiting on this session's caps. if the cap is
823 * old (didn't get renewed on the client reconnect), remove it now.
824 *
825 * caller must hold s_mutex.
826 */
827static int wake_up_session_cb(struct inode *inode, struct ceph_cap *cap,
828 void *arg)
829{
830 struct ceph_inode_info *ci = ceph_inode(inode);
831
832 wake_up(&ci->i_cap_wq);
833 if (arg) {
834 spin_lock(&inode->i_lock);
835 ci->i_wanted_max_size = 0;
836 ci->i_requested_max_size = 0;
837 spin_unlock(&inode->i_lock);
838 }
839 return 0;
840}
841
842static void wake_up_session_caps(struct ceph_mds_session *session,
843 int reconnect)
844{
845 dout("wake_up_session_caps %p mds%d\n", session, session->s_mds);
846 iterate_session_caps(session, wake_up_session_cb,
847 (void *)(unsigned long)reconnect);
848}
849
850/*
851 * Send periodic message to MDS renewing all currently held caps. The
852 * ack will reset the expiration for all caps from this session.
853 *
854 * caller holds s_mutex
855 */
856static int send_renew_caps(struct ceph_mds_client *mdsc,
857 struct ceph_mds_session *session)
858{
859 struct ceph_msg *msg;
860 int state;
861
862 if (time_after_eq(jiffies, session->s_cap_ttl) &&
863 time_after_eq(session->s_cap_ttl, session->s_renew_requested))
864 pr_info("mds%d caps stale\n", session->s_mds);
865
866 /* do not try to renew caps until a recovering mds has reconnected
867 * with its clients. */
868 state = ceph_mdsmap_get_state(mdsc->mdsmap, session->s_mds);
869 if (state < CEPH_MDS_STATE_RECONNECT) {
870 dout("send_renew_caps ignoring mds%d (%s)\n",
871 session->s_mds, ceph_mds_state_name(state));
872 return 0;
873 }
874
875 dout("send_renew_caps to mds%d (%s)\n", session->s_mds,
876 ceph_mds_state_name(state));
877 session->s_renew_requested = jiffies;
878 msg = create_session_msg(CEPH_SESSION_REQUEST_RENEWCAPS,
879 ++session->s_renew_seq);
880 if (IS_ERR(msg))
881 return PTR_ERR(msg);
882 ceph_con_send(&session->s_con, msg);
883 return 0;
884}
885
886/*
887 * Note new cap ttl, and any transition from stale -> not stale (fresh?).
888 *
889 * Called under session->s_mutex
890 */
891static void renewed_caps(struct ceph_mds_client *mdsc,
892 struct ceph_mds_session *session, int is_renew)
893{
894 int was_stale;
895 int wake = 0;
896
897 spin_lock(&session->s_cap_lock);
898 was_stale = is_renew && (session->s_cap_ttl == 0 ||
899 time_after_eq(jiffies, session->s_cap_ttl));
900
901 session->s_cap_ttl = session->s_renew_requested +
902 mdsc->mdsmap->m_session_timeout*HZ;
903
904 if (was_stale) {
905 if (time_before(jiffies, session->s_cap_ttl)) {
906 pr_info("mds%d caps renewed\n", session->s_mds);
907 wake = 1;
908 } else {
909 pr_info("mds%d caps still stale\n", session->s_mds);
910 }
911 }
912 dout("renewed_caps mds%d ttl now %lu, was %s, now %s\n",
913 session->s_mds, session->s_cap_ttl, was_stale ? "stale" : "fresh",
914 time_before(jiffies, session->s_cap_ttl) ? "stale" : "fresh");
915 spin_unlock(&session->s_cap_lock);
916
917 if (wake)
918 wake_up_session_caps(session, 0);
919}
920
921/*
922 * send a session close request
923 */
924static int request_close_session(struct ceph_mds_client *mdsc,
925 struct ceph_mds_session *session)
926{
927 struct ceph_msg *msg;
928 int err = 0;
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);
934 if (IS_ERR(msg))
935 err = PTR_ERR(msg);
936 else
937 ceph_con_send(&session->s_con, msg);
938 return err;
939}
940
941/*
942 * Called with s_mutex held.
943 */
944static int __close_session(struct ceph_mds_client *mdsc,
945 struct ceph_mds_session *session)
946{
947 if (session->s_state >= CEPH_MDS_SESSION_CLOSING)
948 return 0;
949 session->s_state = CEPH_MDS_SESSION_CLOSING;
950 return request_close_session(mdsc, session);
951}
952
953/*
954 * Trim old(er) caps.
955 *
956 * Because we can't cache an inode without one or more caps, we do
957 * this indirectly: if a cap is unused, we prune its aliases, at which
958 * point the inode will hopefully get dropped to.
959 *
960 * Yes, this is a bit sloppy. Our only real goal here is to respond to
961 * memory pressure from the MDS, though, so it needn't be perfect.
962 */
963static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
964{
965 struct ceph_mds_session *session = arg;
966 struct ceph_inode_info *ci = ceph_inode(inode);
967 int used, oissued, mine;
968
969 if (session->s_trim_caps <= 0)
970 return -1;
971
972 spin_lock(&inode->i_lock);
973 mine = cap->issued | cap->implemented;
974 used = __ceph_caps_used(ci);
975 oissued = __ceph_caps_issued_other(ci, cap);
976
977 dout("trim_caps_cb %p cap %p mine %s oissued %s used %s\n",
978 inode, cap, ceph_cap_string(mine), ceph_cap_string(oissued),
979 ceph_cap_string(used));
980 if (ci->i_dirty_caps)
981 goto out; /* dirty caps */
982 if ((used & ~oissued) & mine)
983 goto out; /* we need these caps */
984
985 session->s_trim_caps--;
986 if (oissued) {
987 /* we aren't the only cap.. just remove us */
988 __ceph_remove_cap(cap);
989 } else {
990 /* try to drop referring dentries */
991 spin_unlock(&inode->i_lock);
992 d_prune_aliases(inode);
993 dout("trim_caps_cb %p cap %p pruned, count now %d\n",
994 inode, cap, atomic_read(&inode->i_count));
995 return 0;
996 }
997
998out:
999 spin_unlock(&inode->i_lock);
1000 return 0;
1001}
1002
1003/*
1004 * Trim session cap count down to some max number.
1005 */
1006static int trim_caps(struct ceph_mds_client *mdsc,
1007 struct ceph_mds_session *session,
1008 int max_caps)
1009{
1010 int trim_caps = session->s_nr_caps - max_caps;
1011
1012 dout("trim_caps mds%d start: %d / %d, trim %d\n",
1013 session->s_mds, session->s_nr_caps, max_caps, trim_caps);
1014 if (trim_caps > 0) {
1015 session->s_trim_caps = trim_caps;
1016 iterate_session_caps(session, trim_caps_cb, session);
1017 dout("trim_caps mds%d done: %d / %d, trimmed %d\n",
1018 session->s_mds, session->s_nr_caps, max_caps,
1019 trim_caps - session->s_trim_caps);
1020 session->s_trim_caps = 0;
1021 }
1022 return 0;
1023}
1024
1025/*
1026 * Allocate cap_release messages. If there is a partially full message
1027 * in the queue, try to allocate enough to cover it's remainder, so that
1028 * we can send it immediately.
1029 *
1030 * Called under s_mutex.
1031 */
1032static int add_cap_releases(struct ceph_mds_client *mdsc,
1033 struct ceph_mds_session *session,
1034 int extra)
1035{
1036 struct ceph_msg *msg;
1037 struct ceph_mds_cap_release *head;
1038 int err = -ENOMEM;
1039
1040 if (extra < 0)
1041 extra = mdsc->client->mount_args->cap_release_safety;
1042
1043 spin_lock(&session->s_cap_lock);
1044
1045 if (!list_empty(&session->s_cap_releases)) {
1046 msg = list_first_entry(&session->s_cap_releases,
1047 struct ceph_msg,
1048 list_head);
1049 head = msg->front.iov_base;
1050 extra += CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
1051 }
1052
1053 while (session->s_num_cap_releases < session->s_nr_caps + extra) {
1054 spin_unlock(&session->s_cap_lock);
1055 msg = ceph_msg_new(CEPH_MSG_CLIENT_CAPRELEASE, PAGE_CACHE_SIZE,
1056 0, 0, NULL);
1057 if (!msg)
1058 goto out_unlocked;
1059 dout("add_cap_releases %p msg %p now %d\n", session, msg,
1060 (int)msg->front.iov_len);
1061 head = msg->front.iov_base;
1062 head->num = cpu_to_le32(0);
1063 msg->front.iov_len = sizeof(*head);
1064 spin_lock(&session->s_cap_lock);
1065 list_add(&msg->list_head, &session->s_cap_releases);
1066 session->s_num_cap_releases += CEPH_CAPS_PER_RELEASE;
1067 }
1068
1069 if (!list_empty(&session->s_cap_releases)) {
1070 msg = list_first_entry(&session->s_cap_releases,
1071 struct ceph_msg,
1072 list_head);
1073 head = msg->front.iov_base;
1074 if (head->num) {
1075 dout(" queueing non-full %p (%d)\n", msg,
1076 le32_to_cpu(head->num));
1077 list_move_tail(&msg->list_head,
1078 &session->s_cap_releases_done);
1079 session->s_num_cap_releases -=
1080 CEPH_CAPS_PER_RELEASE - le32_to_cpu(head->num);
1081 }
1082 }
1083 err = 0;
1084 spin_unlock(&session->s_cap_lock);
1085out_unlocked:
1086 return err;
1087}
1088
1089/*
1090 * flush all dirty inode data to disk.
1091 *
1092 * returns true if we've flushed through want_flush_seq
1093 */
1094static int check_cap_flush(struct ceph_mds_client *mdsc, u64 want_flush_seq)
1095{
1096 int mds, ret = 1;
1097
1098 dout("check_cap_flush want %lld\n", want_flush_seq);
1099 mutex_lock(&mdsc->mutex);
1100 for (mds = 0; ret && mds < mdsc->max_sessions; mds++) {
1101 struct ceph_mds_session *session = mdsc->sessions[mds];
1102
1103 if (!session)
1104 continue;
1105 get_session(session);
1106 mutex_unlock(&mdsc->mutex);
1107
1108 mutex_lock(&session->s_mutex);
1109 if (!list_empty(&session->s_cap_flushing)) {
1110 struct ceph_inode_info *ci =
1111 list_entry(session->s_cap_flushing.next,
1112 struct ceph_inode_info,
1113 i_flushing_item);
1114 struct inode *inode = &ci->vfs_inode;
1115
1116 spin_lock(&inode->i_lock);
1117 if (ci->i_cap_flush_seq <= want_flush_seq) {
1118 dout("check_cap_flush still flushing %p "
1119 "seq %lld <= %lld to mds%d\n", inode,
1120 ci->i_cap_flush_seq, want_flush_seq,
1121 session->s_mds);
1122 ret = 0;
1123 }
1124 spin_unlock(&inode->i_lock);
1125 }
1126 mutex_unlock(&session->s_mutex);
1127 ceph_put_mds_session(session);
1128
1129 if (!ret)
1130 return ret;
1131 mutex_lock(&mdsc->mutex);
1132 }
1133
1134 mutex_unlock(&mdsc->mutex);
1135 dout("check_cap_flush ok, flushed thru %lld\n", want_flush_seq);
1136 return ret;
1137}
1138
1139/*
1140 * called under s_mutex
1141 */
1142static void send_cap_releases(struct ceph_mds_client *mdsc,
1143 struct ceph_mds_session *session)
1144{
1145 struct ceph_msg *msg;
1146
1147 dout("send_cap_releases mds%d\n", session->s_mds);
1148 while (1) {
1149 spin_lock(&session->s_cap_lock);
1150 if (list_empty(&session->s_cap_releases_done))
1151 break;
1152 msg = list_first_entry(&session->s_cap_releases_done,
1153 struct ceph_msg, list_head);
1154 list_del_init(&msg->list_head);
1155 spin_unlock(&session->s_cap_lock);
1156 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1157 dout("send_cap_releases mds%d %p\n", session->s_mds, msg);
1158 ceph_con_send(&session->s_con, msg);
1159 }
1160 spin_unlock(&session->s_cap_lock);
1161}
1162
1163/*
1164 * requests
1165 */
1166
1167/*
1168 * Create an mds request.
1169 */
1170struct ceph_mds_request *
1171ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode)
1172{
1173 struct ceph_mds_request *req = kzalloc(sizeof(*req), GFP_NOFS);
1174
1175 if (!req)
1176 return ERR_PTR(-ENOMEM);
1177
1178 req->r_started = jiffies;
1179 req->r_resend_mds = -1;
1180 INIT_LIST_HEAD(&req->r_unsafe_dir_item);
1181 req->r_fmode = -1;
1182 kref_init(&req->r_kref);
1183 INIT_LIST_HEAD(&req->r_wait);
1184 init_completion(&req->r_completion);
1185 init_completion(&req->r_safe_completion);
1186 INIT_LIST_HEAD(&req->r_unsafe_item);
1187
1188 req->r_op = op;
1189 req->r_direct_mode = mode;
1190 return req;
1191}
1192
1193/*
1194 * return oldest (lowest) request, tid in request tree, 0 if none.
1195 *
1196 * called under mdsc->mutex.
1197 */
1198static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
1199{
1200 if (RB_EMPTY_ROOT(&mdsc->request_tree))
1201 return NULL;
1202 return rb_entry(rb_first(&mdsc->request_tree),
1203 struct ceph_mds_request, r_node);
1204}
1205
1206static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
1207{
1208 struct ceph_mds_request *req = __get_oldest_req(mdsc);
1209
1210 if (req)
1211 return req->r_tid;
1212 return 0;
1213}
1214
1215/*
1216 * Build a dentry's path. Allocate on heap; caller must kfree. Based
1217 * on build_path_from_dentry in fs/cifs/dir.c.
1218 *
1219 * If @stop_on_nosnap, generate path relative to the first non-snapped
1220 * inode.
1221 *
1222 * Encode hidden .snap dirs as a double /, i.e.
1223 * foo/.snap/bar -> foo//bar
1224 */
1225char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
1226 int stop_on_nosnap)
1227{
1228 struct dentry *temp;
1229 char *path;
1230 int len, pos;
1231
1232 if (dentry == NULL)
1233 return ERR_PTR(-EINVAL);
1234
1235retry:
1236 len = 0;
1237 for (temp = dentry; !IS_ROOT(temp);) {
1238 struct inode *inode = temp->d_inode;
1239 if (inode && ceph_snap(inode) == CEPH_SNAPDIR)
1240 len++; /* slash only */
1241 else if (stop_on_nosnap && inode &&
1242 ceph_snap(inode) == CEPH_NOSNAP)
1243 break;
1244 else
1245 len += 1 + temp->d_name.len;
1246 temp = temp->d_parent;
1247 if (temp == NULL) {
1248 pr_err("build_path_dentry corrupt dentry %p\n", dentry);
1249 return ERR_PTR(-EINVAL);
1250 }
1251 }
1252 if (len)
1253 len--; /* no leading '/' */
1254
1255 path = kmalloc(len+1, GFP_NOFS);
1256 if (path == NULL)
1257 return ERR_PTR(-ENOMEM);
1258 pos = len;
1259 path[pos] = 0; /* trailing null */
1260 for (temp = dentry; !IS_ROOT(temp) && pos != 0; ) {
1261 struct inode *inode = temp->d_inode;
1262
1263 if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
1264 dout("build_path_dentry path+%d: %p SNAPDIR\n",
1265 pos, temp);
1266 } else if (stop_on_nosnap && inode &&
1267 ceph_snap(inode) == CEPH_NOSNAP) {
1268 break;
1269 } else {
1270 pos -= temp->d_name.len;
1271 if (pos < 0)
1272 break;
1273 strncpy(path + pos, temp->d_name.name,
1274 temp->d_name.len);
1275 dout("build_path_dentry path+%d: %p '%.*s'\n",
1276 pos, temp, temp->d_name.len, path + pos);
1277 }
1278 if (pos)
1279 path[--pos] = '/';
1280 temp = temp->d_parent;
1281 if (temp == NULL) {
1282 pr_err("build_path_dentry corrupt dentry\n");
1283 kfree(path);
1284 return ERR_PTR(-EINVAL);
1285 }
1286 }
1287 if (pos != 0) {
1288 pr_err("build_path_dentry did not end path lookup where "
1289 "expected, namelen is %d, pos is %d\n", len, pos);
1290 /* presumably this is only possible if racing with a
1291 rename of one of the parent directories (we can not
1292 lock the dentries above us to prevent this, but
1293 retrying should be harmless) */
1294 kfree(path);
1295 goto retry;
1296 }
1297
1298 *base = ceph_ino(temp->d_inode);
1299 *plen = len;
1300 dout("build_path_dentry on %p %d built %llx '%.*s'\n",
1301 dentry, atomic_read(&dentry->d_count), *base, len, path);
1302 return path;
1303}
1304
1305static int build_dentry_path(struct dentry *dentry,
1306 const char **ppath, int *ppathlen, u64 *pino,
1307 int *pfreepath)
1308{
1309 char *path;
1310
1311 if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP) {
1312 *pino = ceph_ino(dentry->d_parent->d_inode);
1313 *ppath = dentry->d_name.name;
1314 *ppathlen = dentry->d_name.len;
1315 return 0;
1316 }
1317 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1318 if (IS_ERR(path))
1319 return PTR_ERR(path);
1320 *ppath = path;
1321 *pfreepath = 1;
1322 return 0;
1323}
1324
1325static int build_inode_path(struct inode *inode,
1326 const char **ppath, int *ppathlen, u64 *pino,
1327 int *pfreepath)
1328{
1329 struct dentry *dentry;
1330 char *path;
1331
1332 if (ceph_snap(inode) == CEPH_NOSNAP) {
1333 *pino = ceph_ino(inode);
1334 *ppathlen = 0;
1335 return 0;
1336 }
1337 dentry = d_find_alias(inode);
1338 path = ceph_mdsc_build_path(dentry, ppathlen, pino, 1);
1339 dput(dentry);
1340 if (IS_ERR(path))
1341 return PTR_ERR(path);
1342 *ppath = path;
1343 *pfreepath = 1;
1344 return 0;
1345}
1346
1347/*
1348 * request arguments may be specified via an inode *, a dentry *, or
1349 * an explicit ino+path.
1350 */
1351static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry,
1352 const char *rpath, u64 rino,
1353 const char **ppath, int *pathlen,
1354 u64 *ino, int *freepath)
1355{
1356 int r = 0;
1357
1358 if (rinode) {
1359 r = build_inode_path(rinode, ppath, pathlen, ino, freepath);
1360 dout(" inode %p %llx.%llx\n", rinode, ceph_ino(rinode),
1361 ceph_snap(rinode));
1362 } else if (rdentry) {
1363 r = build_dentry_path(rdentry, ppath, pathlen, ino, freepath);
1364 dout(" dentry %p %llx/%.*s\n", rdentry, *ino, *pathlen,
1365 *ppath);
1366 } else if (rpath) {
1367 *ino = rino;
1368 *ppath = rpath;
1369 *pathlen = strlen(rpath);
1370 dout(" path %.*s\n", *pathlen, rpath);
1371 }
1372
1373 return r;
1374}
1375
1376/*
1377 * called under mdsc->mutex
1378 */
1379static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
1380 struct ceph_mds_request *req,
1381 int mds)
1382{
1383 struct ceph_msg *msg;
1384 struct ceph_mds_request_head *head;
1385 const char *path1 = NULL;
1386 const char *path2 = NULL;
1387 u64 ino1 = 0, ino2 = 0;
1388 int pathlen1 = 0, pathlen2 = 0;
1389 int freepath1 = 0, freepath2 = 0;
1390 int len;
1391 u16 releases;
1392 void *p, *end;
1393 int ret;
1394
1395 ret = set_request_path_attr(req->r_inode, req->r_dentry,
1396 req->r_path1, req->r_ino1.ino,
1397 &path1, &pathlen1, &ino1, &freepath1);
1398 if (ret < 0) {
1399 msg = ERR_PTR(ret);
1400 goto out;
1401 }
1402
1403 ret = set_request_path_attr(NULL, req->r_old_dentry,
1404 req->r_path2, req->r_ino2.ino,
1405 &path2, &pathlen2, &ino2, &freepath2);
1406 if (ret < 0) {
1407 msg = ERR_PTR(ret);
1408 goto out_free1;
1409 }
1410
1411 len = sizeof(*head) +
1412 pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64));
1413
1414 /* calculate (max) length for cap releases */
1415 len += sizeof(struct ceph_mds_request_release) *
1416 (!!req->r_inode_drop + !!req->r_dentry_drop +
1417 !!req->r_old_inode_drop + !!req->r_old_dentry_drop);
1418 if (req->r_dentry_drop)
1419 len += req->r_dentry->d_name.len;
1420 if (req->r_old_dentry_drop)
1421 len += req->r_old_dentry->d_name.len;
1422
1423 msg = ceph_msg_new(CEPH_MSG_CLIENT_REQUEST, len, 0, 0, NULL);
1424 if (IS_ERR(msg))
1425 goto out_free2;
1426
1427 msg->hdr.tid = cpu_to_le64(req->r_tid);
1428
1429 head = msg->front.iov_base;
1430 p = msg->front.iov_base + sizeof(*head);
1431 end = msg->front.iov_base + msg->front.iov_len;
1432
1433 head->mdsmap_epoch = cpu_to_le32(mdsc->mdsmap->m_epoch);
1434 head->op = cpu_to_le32(req->r_op);
1435 head->caller_uid = cpu_to_le32(current_fsuid());
1436 head->caller_gid = cpu_to_le32(current_fsgid());
1437 head->args = req->r_args;
1438
1439 ceph_encode_filepath(&p, end, ino1, path1);
1440 ceph_encode_filepath(&p, end, ino2, path2);
1441
1442 /* cap releases */
1443 releases = 0;
1444 if (req->r_inode_drop)
1445 releases += ceph_encode_inode_release(&p,
1446 req->r_inode ? req->r_inode : req->r_dentry->d_inode,
1447 mds, req->r_inode_drop, req->r_inode_unless, 0);
1448 if (req->r_dentry_drop)
1449 releases += ceph_encode_dentry_release(&p, req->r_dentry,
1450 mds, req->r_dentry_drop, req->r_dentry_unless);
1451 if (req->r_old_dentry_drop)
1452 releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
1453 mds, req->r_old_dentry_drop, req->r_old_dentry_unless);
1454 if (req->r_old_inode_drop)
1455 releases += ceph_encode_inode_release(&p,
1456 req->r_old_dentry->d_inode,
1457 mds, req->r_old_inode_drop, req->r_old_inode_unless, 0);
1458 head->num_releases = cpu_to_le16(releases);
1459
1460 BUG_ON(p > end);
1461 msg->front.iov_len = p - msg->front.iov_base;
1462 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
1463
1464 msg->pages = req->r_pages;
1465 msg->nr_pages = req->r_num_pages;
1466 msg->hdr.data_len = cpu_to_le32(req->r_data_len);
1467 msg->hdr.data_off = cpu_to_le16(0);
1468
1469out_free2:
1470 if (freepath2)
1471 kfree((char *)path2);
1472out_free1:
1473 if (freepath1)
1474 kfree((char *)path1);
1475out:
1476 return msg;
1477}
1478
1479/*
1480 * called under mdsc->mutex if error, under no mutex if
1481 * success.
1482 */
1483static void complete_request(struct ceph_mds_client *mdsc,
1484 struct ceph_mds_request *req)
1485{
1486 if (req->r_callback)
1487 req->r_callback(mdsc, req);
1488 else
1489 complete(&req->r_completion);
1490}
1491
1492/*
1493 * called under mdsc->mutex
1494 */
1495static int __prepare_send_request(struct ceph_mds_client *mdsc,
1496 struct ceph_mds_request *req,
1497 int mds)
1498{
1499 struct ceph_mds_request_head *rhead;
1500 struct ceph_msg *msg;
1501 int flags = 0;
1502
1503 req->r_mds = mds;
1504 req->r_attempts++;
1505 dout("prepare_send_request %p tid %lld %s (attempt %d)\n", req,
1506 req->r_tid, ceph_mds_op_name(req->r_op), req->r_attempts);
1507
1508 if (req->r_request) {
1509 ceph_msg_put(req->r_request);
1510 req->r_request = NULL;
1511 }
1512 msg = create_request_message(mdsc, req, mds);
1513 if (IS_ERR(msg)) {
1514 req->r_reply = ERR_PTR(PTR_ERR(msg));
1515 complete_request(mdsc, req);
1516 return -PTR_ERR(msg);
1517 }
1518 req->r_request = msg;
1519
1520 rhead = msg->front.iov_base;
1521 rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
1522 if (req->r_got_unsafe)
1523 flags |= CEPH_MDS_FLAG_REPLAY;
1524 if (req->r_locked_dir)
1525 flags |= CEPH_MDS_FLAG_WANT_DENTRY;
1526 rhead->flags = cpu_to_le32(flags);
1527 rhead->num_fwd = req->r_num_fwd;
1528 rhead->num_retry = req->r_attempts - 1;
1529
1530 dout(" r_locked_dir = %p\n", req->r_locked_dir);
1531
1532 if (req->r_target_inode && req->r_got_unsafe)
1533 rhead->ino = cpu_to_le64(ceph_ino(req->r_target_inode));
1534 else
1535 rhead->ino = 0;
1536 return 0;
1537}
1538
1539/*
1540 * send request, or put it on the appropriate wait list.
1541 */
1542static int __do_request(struct ceph_mds_client *mdsc,
1543 struct ceph_mds_request *req)
1544{
1545 struct ceph_mds_session *session = NULL;
1546 int mds = -1;
1547 int err = -EAGAIN;
1548
1549 if (req->r_reply)
1550 goto out;
1551
1552 if (req->r_timeout &&
1553 time_after_eq(jiffies, req->r_started + req->r_timeout)) {
1554 dout("do_request timed out\n");
1555 err = -EIO;
1556 goto finish;
1557 }
1558
1559 mds = __choose_mds(mdsc, req);
1560 if (mds < 0 ||
1561 ceph_mdsmap_get_state(mdsc->mdsmap, mds) < CEPH_MDS_STATE_ACTIVE) {
1562 dout("do_request no mds or not active, waiting for map\n");
1563 list_add(&req->r_wait, &mdsc->waiting_for_map);
1564 goto out;
1565 }
1566
1567 /* get, open session */
1568 session = __ceph_lookup_mds_session(mdsc, mds);
1569 if (!session)
1570 session = register_session(mdsc, mds);
1571 dout("do_request mds%d session %p state %s\n", mds, session,
1572 session_state_name(session->s_state));
1573 if (session->s_state != CEPH_MDS_SESSION_OPEN &&
1574 session->s_state != CEPH_MDS_SESSION_HUNG) {
1575 if (session->s_state == CEPH_MDS_SESSION_NEW ||
1576 session->s_state == CEPH_MDS_SESSION_CLOSING)
1577 __open_session(mdsc, session);
1578 list_add(&req->r_wait, &session->s_waiting);
1579 goto out_session;
1580 }
1581
1582 /* send request */
1583 req->r_session = get_session(session);
1584 req->r_resend_mds = -1; /* forget any previous mds hint */
1585
1586 if (req->r_request_started == 0) /* note request start time */
1587 req->r_request_started = jiffies;
1588
1589 err = __prepare_send_request(mdsc, req, mds);
1590 if (!err) {
1591 ceph_msg_get(req->r_request);
1592 ceph_con_send(&session->s_con, req->r_request);
1593 }
1594
1595out_session:
1596 ceph_put_mds_session(session);
1597out:
1598 return err;
1599
1600finish:
1601 req->r_reply = ERR_PTR(err);
1602 complete_request(mdsc, req);
1603 goto out;
1604}
1605
1606/*
1607 * called under mdsc->mutex
1608 */
1609static void __wake_requests(struct ceph_mds_client *mdsc,
1610 struct list_head *head)
1611{
1612 struct ceph_mds_request *req, *nreq;
1613
1614 list_for_each_entry_safe(req, nreq, head, r_wait) {
1615 list_del_init(&req->r_wait);
1616 __do_request(mdsc, req);
1617 }
1618}
1619
1620/*
1621 * Wake up threads with requests pending for @mds, so that they can
1622 * resubmit their requests to a possibly different mds. If @all is set,
1623 * wake up if their requests has been forwarded to @mds, too.
1624 */
1625static void kick_requests(struct ceph_mds_client *mdsc, int mds, int all)
1626{
1627 struct ceph_mds_request *req;
1628 struct rb_node *p;
1629
1630 dout("kick_requests mds%d\n", mds);
1631 for (p = rb_first(&mdsc->request_tree); p; p = rb_next(p)) {
1632 req = rb_entry(p, struct ceph_mds_request, r_node);
1633 if (req->r_got_unsafe)
1634 continue;
1635 if (req->r_session &&
1636 req->r_session->s_mds == mds) {
1637 dout(" kicking tid %llu\n", req->r_tid);
1638 put_request_session(req);
1639 __do_request(mdsc, req);
1640 }
1641 }
1642}
1643
1644void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
1645 struct ceph_mds_request *req)
1646{
1647 dout("submit_request on %p\n", req);
1648 mutex_lock(&mdsc->mutex);
1649 __register_request(mdsc, req, NULL);
1650 __do_request(mdsc, req);
1651 mutex_unlock(&mdsc->mutex);
1652}
1653
1654/*
1655 * Synchrously perform an mds request. Take care of all of the
1656 * session setup, forwarding, retry details.
1657 */
1658int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
1659 struct inode *dir,
1660 struct ceph_mds_request *req)
1661{
1662 int err;
1663
1664 dout("do_request on %p\n", req);
1665
1666 /* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
1667 if (req->r_inode)
1668 ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
1669 if (req->r_locked_dir)
1670 ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
1671 if (req->r_old_dentry)
1672 ceph_get_cap_refs(
1673 ceph_inode(req->r_old_dentry->d_parent->d_inode),
1674 CEPH_CAP_PIN);
1675
1676 /* issue */
1677 mutex_lock(&mdsc->mutex);
1678 __register_request(mdsc, req, dir);
1679 __do_request(mdsc, req);
1680
1681 /* wait */
1682 if (!req->r_reply) {
1683 mutex_unlock(&mdsc->mutex);
1684 if (req->r_timeout) {
1685 err = (long)wait_for_completion_interruptible_timeout(
1686 &req->r_completion, req->r_timeout);
1687 if (err == 0)
1688 req->r_reply = ERR_PTR(-EIO);
1689 else if (err < 0)
1690 req->r_reply = ERR_PTR(err);
1691 } else {
1692 err = wait_for_completion_interruptible(
1693 &req->r_completion);
1694 if (err)
1695 req->r_reply = ERR_PTR(err);
1696 }
1697 mutex_lock(&mdsc->mutex);
1698 }
1699
1700 if (IS_ERR(req->r_reply)) {
1701 err = PTR_ERR(req->r_reply);
1702 req->r_reply = NULL;
1703
1704 if (err == -ERESTARTSYS) {
1705 /* aborted */
1706 req->r_aborted = true;
1707
1708 if (req->r_locked_dir &&
1709 (req->r_op & CEPH_MDS_OP_WRITE)) {
1710 struct ceph_inode_info *ci =
1711 ceph_inode(req->r_locked_dir);
1712
1713 dout("aborted, clearing I_COMPLETE on %p\n",
1714 req->r_locked_dir);
1715 spin_lock(&req->r_locked_dir->i_lock);
1716 ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
1717 ci->i_release_count++;
1718 spin_unlock(&req->r_locked_dir->i_lock);
1719 }
1720 } else {
1721 /* clean up this request */
1722 __unregister_request(mdsc, req);
1723 if (!list_empty(&req->r_unsafe_item))
1724 list_del_init(&req->r_unsafe_item);
1725 complete(&req->r_safe_completion);
1726 }
1727 } else if (req->r_err) {
1728 err = req->r_err;
1729 } else {
1730 err = le32_to_cpu(req->r_reply_info.head->result);
1731 }
1732 mutex_unlock(&mdsc->mutex);
1733
1734 dout("do_request %p done, result %d\n", req, err);
1735 return err;
1736}
1737
1738/*
1739 * Handle mds reply.
1740 *
1741 * We take the session mutex and parse and process the reply immediately.
1742 * This preserves the logical ordering of replies, capabilities, etc., sent
1743 * by the MDS as they are applied to our local cache.
1744 */
1745static void handle_reply(struct ceph_mds_session *session, struct ceph_msg *msg)
1746{
1747 struct ceph_mds_client *mdsc = session->s_mdsc;
1748 struct ceph_mds_request *req;
1749 struct ceph_mds_reply_head *head = msg->front.iov_base;
1750 struct ceph_mds_reply_info_parsed *rinfo; /* parsed reply info */
1751 u64 tid;
1752 int err, result;
1753 int mds = session->s_mds;
1754
1755 if (msg->front.iov_len < sizeof(*head)) {
1756 pr_err("mdsc_handle_reply got corrupt (short) reply\n");
1757 ceph_msg_dump(msg);
1758 return;
1759 }
1760
1761 /* get request, session */
1762 tid = le64_to_cpu(msg->hdr.tid);
1763 mutex_lock(&mdsc->mutex);
1764 req = __lookup_request(mdsc, tid);
1765 if (!req) {
1766 dout("handle_reply on unknown tid %llu\n", tid);
1767 mutex_unlock(&mdsc->mutex);
1768 return;
1769 }
1770 dout("handle_reply %p\n", req);
1771
1772 /* correct session? */
1773 if (!req->r_session && req->r_session != session) {
1774 pr_err("mdsc_handle_reply got %llu on session mds%d"
1775 " not mds%d\n", tid, session->s_mds,
1776 req->r_session ? req->r_session->s_mds : -1);
1777 mutex_unlock(&mdsc->mutex);
1778 goto out;
1779 }
1780
1781 /* dup? */
1782 if ((req->r_got_unsafe && !head->safe) ||
1783 (req->r_got_safe && head->safe)) {
1784 pr_warning("got a dup %s reply on %llu from mds%d\n",
1785 head->safe ? "safe" : "unsafe", tid, mds);
1786 mutex_unlock(&mdsc->mutex);
1787 goto out;
1788 }
1789
1790 result = le32_to_cpu(head->result);
1791
1792 /*
1793 * Tolerate 2 consecutive ESTALEs from the same mds.
1794 * FIXME: we should be looking at the cap migrate_seq.
1795 */
1796 if (result == -ESTALE) {
1797 req->r_direct_mode = USE_AUTH_MDS;
1798 req->r_num_stale++;
1799 if (req->r_num_stale <= 2) {
1800 __do_request(mdsc, req);
1801 mutex_unlock(&mdsc->mutex);
1802 goto out;
1803 }
1804 } else {
1805 req->r_num_stale = 0;
1806 }
1807
1808 if (head->safe) {
1809 req->r_got_safe = true;
1810 __unregister_request(mdsc, req);
1811 complete(&req->r_safe_completion);
1812
1813 if (req->r_got_unsafe) {
1814 /*
1815 * We already handled the unsafe response, now do the
1816 * cleanup. No need to examine the response; the MDS
1817 * doesn't include any result info in the safe
1818 * response. And even if it did, there is nothing
1819 * useful we could do with a revised return value.
1820 */
1821 dout("got safe reply %llu, mds%d\n", tid, mds);
1822 list_del_init(&req->r_unsafe_item);
1823
1824 /* last unsafe request during umount? */
1825 if (mdsc->stopping && !__get_oldest_req(mdsc))
1826 complete(&mdsc->safe_umount_waiters);
1827 mutex_unlock(&mdsc->mutex);
1828 goto out;
1829 }
1830 }
1831
1832 BUG_ON(req->r_reply);
1833
1834 if (!head->safe) {
1835 req->r_got_unsafe = true;
1836 list_add_tail(&req->r_unsafe_item, &req->r_session->s_unsafe);
1837 }
1838
1839 dout("handle_reply tid %lld result %d\n", tid, result);
1840 rinfo = &req->r_reply_info;
1841 err = parse_reply_info(msg, rinfo);
1842 mutex_unlock(&mdsc->mutex);
1843
1844 mutex_lock(&session->s_mutex);
1845 if (err < 0) {
1846 pr_err("mdsc_handle_reply got corrupt reply mds%d\n", mds);
1847 ceph_msg_dump(msg);
1848 goto out_err;
1849 }
1850
1851 /* snap trace */
1852 if (rinfo->snapblob_len) {
1853 down_write(&mdsc->snap_rwsem);
1854 ceph_update_snap_trace(mdsc, rinfo->snapblob,
1855 rinfo->snapblob + rinfo->snapblob_len,
1856 le32_to_cpu(head->op) == CEPH_MDS_OP_RMSNAP);
1857 downgrade_write(&mdsc->snap_rwsem);
1858 } else {
1859 down_read(&mdsc->snap_rwsem);
1860 }
1861
1862 /* insert trace into our cache */
1863 err = ceph_fill_trace(mdsc->client->sb, req, req->r_session);
1864 if (err == 0) {
1865 if (result == 0 && rinfo->dir_nr)
1866 ceph_readdir_prepopulate(req, req->r_session);
1867 ceph_unreserve_caps(&req->r_caps_reservation);
1868 }
1869
1870 up_read(&mdsc->snap_rwsem);
1871out_err:
1872 if (err) {
1873 req->r_err = err;
1874 } else {
1875 req->r_reply = msg;
1876 ceph_msg_get(msg);
1877 }
1878
1879 add_cap_releases(mdsc, req->r_session, -1);
1880 mutex_unlock(&session->s_mutex);
1881
1882 /* kick calling process */
1883 complete_request(mdsc, req);
1884out:
1885 ceph_mdsc_put_request(req);
1886 return;
1887}
1888
1889
1890
1891/*
1892 * handle mds notification that our request has been forwarded.
1893 */
1894static void handle_forward(struct ceph_mds_client *mdsc,
1895 struct ceph_mds_session *session,
1896 struct ceph_msg *msg)
1897{
1898 struct ceph_mds_request *req;
1899 u64 tid = le64_to_cpu(msg->hdr.tid);
1900 u32 next_mds;
1901 u32 fwd_seq;
1902 int err = -EINVAL;
1903 void *p = msg->front.iov_base;
1904 void *end = p + msg->front.iov_len;
1905
1906 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
1907 next_mds = ceph_decode_32(&p);
1908 fwd_seq = ceph_decode_32(&p);
1909
1910 mutex_lock(&mdsc->mutex);
1911 req = __lookup_request(mdsc, tid);
1912 if (!req) {
1913 dout("forward %llu to mds%d - req dne\n", tid, next_mds);
1914 goto out; /* dup reply? */
1915 }
1916
1917 if (fwd_seq <= req->r_num_fwd) {
1918 dout("forward %llu to mds%d - old seq %d <= %d\n",
1919 tid, next_mds, req->r_num_fwd, fwd_seq);
1920 } else {
1921 /* resend. forward race not possible; mds would drop */
1922 dout("forward %llu to mds%d (we resend)\n", tid, next_mds);
1923 req->r_num_fwd = fwd_seq;
1924 req->r_resend_mds = next_mds;
1925 put_request_session(req);
1926 __do_request(mdsc, req);
1927 }
1928 ceph_mdsc_put_request(req);
1929out:
1930 mutex_unlock(&mdsc->mutex);
1931 return;
1932
1933bad:
1934 pr_err("mdsc_handle_forward decode error err=%d\n", err);
1935}
1936
1937/*
1938 * handle a mds session control message
1939 */
1940static void handle_session(struct ceph_mds_session *session,
1941 struct ceph_msg *msg)
1942{
1943 struct ceph_mds_client *mdsc = session->s_mdsc;
1944 u32 op;
1945 u64 seq;
1946 int mds = session->s_mds;
1947 struct ceph_mds_session_head *h = msg->front.iov_base;
1948 int wake = 0;
1949
1950 /* decode */
1951 if (msg->front.iov_len != sizeof(*h))
1952 goto bad;
1953 op = le32_to_cpu(h->op);
1954 seq = le64_to_cpu(h->seq);
1955
1956 mutex_lock(&mdsc->mutex);
1957 if (op == CEPH_SESSION_CLOSE)
1958 __unregister_session(mdsc, session);
1959 /* FIXME: this ttl calculation is generous */
1960 session->s_ttl = jiffies + HZ*mdsc->mdsmap->m_session_autoclose;
1961 mutex_unlock(&mdsc->mutex);
1962
1963 mutex_lock(&session->s_mutex);
1964
1965 dout("handle_session mds%d %s %p state %s seq %llu\n",
1966 mds, ceph_session_op_name(op), session,
1967 session_state_name(session->s_state), seq);
1968
1969 if (session->s_state == CEPH_MDS_SESSION_HUNG) {
1970 session->s_state = CEPH_MDS_SESSION_OPEN;
1971 pr_info("mds%d came back\n", session->s_mds);
1972 }
1973
1974 switch (op) {
1975 case CEPH_SESSION_OPEN:
1976 session->s_state = CEPH_MDS_SESSION_OPEN;
1977 renewed_caps(mdsc, session, 0);
1978 wake = 1;
1979 if (mdsc->stopping)
1980 __close_session(mdsc, session);
1981 break;
1982
1983 case CEPH_SESSION_RENEWCAPS:
1984 if (session->s_renew_seq == seq)
1985 renewed_caps(mdsc, session, 1);
1986 break;
1987
1988 case CEPH_SESSION_CLOSE:
1989 remove_session_caps(session);
1990 wake = 1; /* for good measure */
1991 complete(&mdsc->session_close_waiters);
1992 kick_requests(mdsc, mds, 0); /* cur only */
1993 break;
1994
1995 case CEPH_SESSION_STALE:
1996 pr_info("mds%d caps went stale, renewing\n",
1997 session->s_mds);
1998 spin_lock(&session->s_cap_lock);
1999 session->s_cap_gen++;
2000 session->s_cap_ttl = 0;
2001 spin_unlock(&session->s_cap_lock);
2002 send_renew_caps(mdsc, session);
2003 break;
2004
2005 case CEPH_SESSION_RECALL_STATE:
2006 trim_caps(mdsc, session, le32_to_cpu(h->max_caps));
2007 break;
2008
2009 default:
2010 pr_err("mdsc_handle_session bad op %d mds%d\n", op, mds);
2011 WARN_ON(1);
2012 }
2013
2014 mutex_unlock(&session->s_mutex);
2015 if (wake) {
2016 mutex_lock(&mdsc->mutex);
2017 __wake_requests(mdsc, &session->s_waiting);
2018 mutex_unlock(&mdsc->mutex);
2019 }
2020 return;
2021
2022bad:
2023 pr_err("mdsc_handle_session corrupt message mds%d len %d\n", mds,
2024 (int)msg->front.iov_len);
2025 ceph_msg_dump(msg);
2026 return;
2027}
2028
2029
2030/*
2031 * called under session->mutex.
2032 */
2033static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
2034 struct ceph_mds_session *session)
2035{
2036 struct ceph_mds_request *req, *nreq;
2037 int err;
2038
2039 dout("replay_unsafe_requests mds%d\n", session->s_mds);
2040
2041 mutex_lock(&mdsc->mutex);
2042 list_for_each_entry_safe(req, nreq, &session->s_unsafe, r_unsafe_item) {
2043 err = __prepare_send_request(mdsc, req, session->s_mds);
2044 if (!err) {
2045 ceph_msg_get(req->r_request);
2046 ceph_con_send(&session->s_con, req->r_request);
2047 }
2048 }
2049 mutex_unlock(&mdsc->mutex);
2050}
2051
2052/*
2053 * Encode information about a cap for a reconnect with the MDS.
2054 */
2055static int encode_caps_cb(struct inode *inode, struct ceph_cap *cap,
2056 void *arg)
2057{
2058 struct ceph_mds_cap_reconnect rec;
2059 struct ceph_inode_info *ci;
2060 struct ceph_pagelist *pagelist = arg;
2061 char *path;
2062 int pathlen, err;
2063 u64 pathbase;
2064 struct dentry *dentry;
2065
2066 ci = cap->ci;
2067
2068 dout(" adding %p ino %llx.%llx cap %p %lld %s\n",
2069 inode, ceph_vinop(inode), cap, cap->cap_id,
2070 ceph_cap_string(cap->issued));
2071 err = ceph_pagelist_encode_64(pagelist, ceph_ino(inode));
2072 if (err)
2073 return err;
2074
2075 dentry = d_find_alias(inode);
2076 if (dentry) {
2077 path = ceph_mdsc_build_path(dentry, &pathlen, &pathbase, 0);
2078 if (IS_ERR(path)) {
2079 err = PTR_ERR(path);
2080 BUG_ON(err);
2081 }
2082 } else {
2083 path = NULL;
2084 pathlen = 0;
2085 }
2086 err = ceph_pagelist_encode_string(pagelist, path, pathlen);
2087 if (err)
2088 goto out;
2089
2090 spin_lock(&inode->i_lock);
2091 cap->seq = 0; /* reset cap seq */
2092 cap->issue_seq = 0; /* and issue_seq */
2093 rec.cap_id = cpu_to_le64(cap->cap_id);
2094 rec.pathbase = cpu_to_le64(pathbase);
2095 rec.wanted = cpu_to_le32(__ceph_caps_wanted(ci));
2096 rec.issued = cpu_to_le32(cap->issued);
2097 rec.size = cpu_to_le64(inode->i_size);
2098 ceph_encode_timespec(&rec.mtime, &inode->i_mtime);
2099 ceph_encode_timespec(&rec.atime, &inode->i_atime);
2100 rec.snaprealm = cpu_to_le64(ci->i_snap_realm->ino);
2101 spin_unlock(&inode->i_lock);
2102
2103 err = ceph_pagelist_append(pagelist, &rec, sizeof(rec));
2104
2105out:
2106 kfree(path);
2107 dput(dentry);
2108 return err;
2109}
2110
2111
2112/*
2113 * If an MDS fails and recovers, clients need to reconnect in order to
2114 * reestablish shared state. This includes all caps issued through
2115 * this session _and_ the snap_realm hierarchy. Because it's not
2116 * clear which snap realms the mds cares about, we send everything we
2117 * know about.. that ensures we'll then get any new info the
2118 * recovering MDS might have.
2119 *
2120 * This is a relatively heavyweight operation, but it's rare.
2121 *
2122 * called with mdsc->mutex held.
2123 */
2124static void send_mds_reconnect(struct ceph_mds_client *mdsc, int mds)
2125{
2126 struct ceph_mds_session *session = NULL;
2127 struct ceph_msg *reply;
2128 struct rb_node *p;
2129 int err;
2130 struct ceph_pagelist *pagelist;
2131
2132 pr_info("reconnect to recovering mds%d\n", mds);
2133
2134 pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
2135 if (!pagelist)
2136 goto fail_nopagelist;
2137 ceph_pagelist_init(pagelist);
2138
2139 reply = ceph_msg_new(CEPH_MSG_CLIENT_RECONNECT, 0, 0, 0, NULL);
2140 if (IS_ERR(reply)) {
2141 err = PTR_ERR(reply);
2142 goto fail_nomsg;
2143 }
2144
2145 /* find session */
2146 session = __ceph_lookup_mds_session(mdsc, mds);
2147 mutex_unlock(&mdsc->mutex); /* drop lock for duration */
2148
2149 if (session) {
2150 mutex_lock(&session->s_mutex);
2151
2152 session->s_state = CEPH_MDS_SESSION_RECONNECTING;
2153 session->s_seq = 0;
2154
2155 ceph_con_open(&session->s_con,
2156 ceph_mdsmap_get_addr(mdsc->mdsmap, mds));
2157
2158 /* replay unsafe requests */
2159 replay_unsafe_requests(mdsc, session);
2160 } else {
2161 dout("no session for mds%d, will send short reconnect\n",
2162 mds);
2163 }
2164
2165 down_read(&mdsc->snap_rwsem);
2166
2167 if (!session)
2168 goto send;
2169 dout("session %p state %s\n", session,
2170 session_state_name(session->s_state));
2171
2172 /* traverse this session's caps */
2173 err = ceph_pagelist_encode_32(pagelist, session->s_nr_caps);
2174 if (err)
2175 goto fail;
2176 err = iterate_session_caps(session, encode_caps_cb, pagelist);
2177 if (err < 0)
2178 goto out;
2179
2180 /*
2181 * snaprealms. we provide mds with the ino, seq (version), and
2182 * parent for all of our realms. If the mds has any newer info,
2183 * it will tell us.
2184 */
2185 for (p = rb_first(&mdsc->snap_realms); p; p = rb_next(p)) {
2186 struct ceph_snap_realm *realm =
2187 rb_entry(p, struct ceph_snap_realm, node);
2188 struct ceph_mds_snaprealm_reconnect sr_rec;
2189
2190 dout(" adding snap realm %llx seq %lld parent %llx\n",
2191 realm->ino, realm->seq, realm->parent_ino);
2192 sr_rec.ino = cpu_to_le64(realm->ino);
2193 sr_rec.seq = cpu_to_le64(realm->seq);
2194 sr_rec.parent = cpu_to_le64(realm->parent_ino);
2195 err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
2196 if (err)
2197 goto fail;
2198 }
2199
2200send:
2201 reply->pagelist = pagelist;
2202 reply->hdr.data_len = cpu_to_le32(pagelist->length);
2203 reply->nr_pages = calc_pages_for(0, pagelist->length);
2204 ceph_con_send(&session->s_con, reply);
2205
2206 if (session) {
2207 session->s_state = CEPH_MDS_SESSION_OPEN;
2208 __wake_requests(mdsc, &session->s_waiting);
2209 }
2210
2211out:
2212 up_read(&mdsc->snap_rwsem);
2213 if (session) {
2214 mutex_unlock(&session->s_mutex);
2215 ceph_put_mds_session(session);
2216 }
2217 mutex_lock(&mdsc->mutex);
2218 return;
2219
2220fail:
2221 ceph_msg_put(reply);
2222fail_nomsg:
2223 ceph_pagelist_release(pagelist);
2224 kfree(pagelist);
2225fail_nopagelist:
2226 pr_err("ENOMEM preparing reconnect for mds%d\n", mds);
2227 goto out;
2228}
2229
2230
2231/*
2232 * compare old and new mdsmaps, kicking requests
2233 * and closing out old connections as necessary
2234 *
2235 * called under mdsc->mutex.
2236 */
2237static void check_new_map(struct ceph_mds_client *mdsc,
2238 struct ceph_mdsmap *newmap,
2239 struct ceph_mdsmap *oldmap)
2240{
2241 int i;
2242 int oldstate, newstate;
2243 struct ceph_mds_session *s;
2244
2245 dout("check_new_map new %u old %u\n",
2246 newmap->m_epoch, oldmap->m_epoch);
2247
2248 for (i = 0; i < oldmap->m_max_mds && i < mdsc->max_sessions; i++) {
2249 if (mdsc->sessions[i] == NULL)
2250 continue;
2251 s = mdsc->sessions[i];
2252 oldstate = ceph_mdsmap_get_state(oldmap, i);
2253 newstate = ceph_mdsmap_get_state(newmap, i);
2254
2255 dout("check_new_map mds%d state %s -> %s (session %s)\n",
2256 i, ceph_mds_state_name(oldstate),
2257 ceph_mds_state_name(newstate),
2258 session_state_name(s->s_state));
2259
2260 if (memcmp(ceph_mdsmap_get_addr(oldmap, i),
2261 ceph_mdsmap_get_addr(newmap, i),
2262 sizeof(struct ceph_entity_addr))) {
2263 if (s->s_state == CEPH_MDS_SESSION_OPENING) {
2264 /* the session never opened, just close it
2265 * out now */
2266 __wake_requests(mdsc, &s->s_waiting);
2267 __unregister_session(mdsc, s);
2268 } else {
2269 /* just close it */
2270 mutex_unlock(&mdsc->mutex);
2271 mutex_lock(&s->s_mutex);
2272 mutex_lock(&mdsc->mutex);
2273 ceph_con_close(&s->s_con);
2274 mutex_unlock(&s->s_mutex);
2275 s->s_state = CEPH_MDS_SESSION_RESTARTING;
2276 }
2277
2278 /* kick any requests waiting on the recovering mds */
2279 kick_requests(mdsc, i, 1);
2280 } else if (oldstate == newstate) {
2281 continue; /* nothing new with this mds */
2282 }
2283
2284 /*
2285 * send reconnect?
2286 */
2287 if (s->s_state == CEPH_MDS_SESSION_RESTARTING &&
2288 newstate >= CEPH_MDS_STATE_RECONNECT)
2289 send_mds_reconnect(mdsc, i);
2290
2291 /*
2292 * kick requests on any mds that has gone active.
2293 *
2294 * kick requests on cur or forwarder: we may have sent
2295 * the request to mds1, mds1 told us it forwarded it
2296 * to mds2, but then we learn mds1 failed and can't be
2297 * sure it successfully forwarded our request before
2298 * it died.
2299 */
2300 if (oldstate < CEPH_MDS_STATE_ACTIVE &&
2301 newstate >= CEPH_MDS_STATE_ACTIVE) {
2302 pr_info("mds%d reconnect completed\n", s->s_mds);
2303 kick_requests(mdsc, i, 1);
2304 ceph_kick_flushing_caps(mdsc, s);
2305 wake_up_session_caps(s, 1);
2306 }
2307 }
2308}
2309
2310
2311
2312/*
2313 * leases
2314 */
2315
2316/*
2317 * caller must hold session s_mutex, dentry->d_lock
2318 */
2319void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry)
2320{
2321 struct ceph_dentry_info *di = ceph_dentry(dentry);
2322
2323 ceph_put_mds_session(di->lease_session);
2324 di->lease_session = NULL;
2325}
2326
2327static void handle_lease(struct ceph_mds_client *mdsc,
2328 struct ceph_mds_session *session,
2329 struct ceph_msg *msg)
2330{
2331 struct super_block *sb = mdsc->client->sb;
2332 struct inode *inode;
2333 struct ceph_inode_info *ci;
2334 struct dentry *parent, *dentry;
2335 struct ceph_dentry_info *di;
2336 int mds = session->s_mds;
2337 struct ceph_mds_lease *h = msg->front.iov_base;
2338 struct ceph_vino vino;
2339 int mask;
2340 struct qstr dname;
2341 int release = 0;
2342
2343 dout("handle_lease from mds%d\n", mds);
2344
2345 /* decode */
2346 if (msg->front.iov_len < sizeof(*h) + sizeof(u32))
2347 goto bad;
2348 vino.ino = le64_to_cpu(h->ino);
2349 vino.snap = CEPH_NOSNAP;
2350 mask = le16_to_cpu(h->mask);
2351 dname.name = (void *)h + sizeof(*h) + sizeof(u32);
2352 dname.len = msg->front.iov_len - sizeof(*h) - sizeof(u32);
2353 if (dname.len != get_unaligned_le32(h+1))
2354 goto bad;
2355
2356 mutex_lock(&session->s_mutex);
2357 session->s_seq++;
2358
2359 /* lookup inode */
2360 inode = ceph_find_inode(sb, vino);
2361 dout("handle_lease '%s', mask %d, ino %llx %p\n",
2362 ceph_lease_op_name(h->action), mask, vino.ino, inode);
2363 if (inode == NULL) {
2364 dout("handle_lease no inode %llx\n", vino.ino);
2365 goto release;
2366 }
2367 ci = ceph_inode(inode);
2368
2369 /* dentry */
2370 parent = d_find_alias(inode);
2371 if (!parent) {
2372 dout("no parent dentry on inode %p\n", inode);
2373 WARN_ON(1);
2374 goto release; /* hrm... */
2375 }
2376 dname.hash = full_name_hash(dname.name, dname.len);
2377 dentry = d_lookup(parent, &dname);
2378 dput(parent);
2379 if (!dentry)
2380 goto release;
2381
2382 spin_lock(&dentry->d_lock);
2383 di = ceph_dentry(dentry);
2384 switch (h->action) {
2385 case CEPH_MDS_LEASE_REVOKE:
2386 if (di && di->lease_session == session) {
2387 h->seq = cpu_to_le32(di->lease_seq);
2388 __ceph_mdsc_drop_dentry_lease(dentry);
2389 }
2390 release = 1;
2391 break;
2392
2393 case CEPH_MDS_LEASE_RENEW:
2394 if (di && di->lease_session == session &&
2395 di->lease_gen == session->s_cap_gen &&
2396 di->lease_renew_from &&
2397 di->lease_renew_after == 0) {
2398 unsigned long duration =
2399 le32_to_cpu(h->duration_ms) * HZ / 1000;
2400
2401 di->lease_seq = le32_to_cpu(h->seq);
2402 dentry->d_time = di->lease_renew_from + duration;
2403 di->lease_renew_after = di->lease_renew_from +
2404 (duration >> 1);
2405 di->lease_renew_from = 0;
2406 }
2407 break;
2408 }
2409 spin_unlock(&dentry->d_lock);
2410 dput(dentry);
2411
2412 if (!release)
2413 goto out;
2414
2415release:
2416 /* let's just reuse the same message */
2417 h->action = CEPH_MDS_LEASE_REVOKE_ACK;
2418 ceph_msg_get(msg);
2419 ceph_con_send(&session->s_con, msg);
2420
2421out:
2422 iput(inode);
2423 mutex_unlock(&session->s_mutex);
2424 return;
2425
2426bad:
2427 pr_err("corrupt lease message\n");
2428 ceph_msg_dump(msg);
2429}
2430
2431void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
2432 struct inode *inode,
2433 struct dentry *dentry, char action,
2434 u32 seq)
2435{
2436 struct ceph_msg *msg;
2437 struct ceph_mds_lease *lease;
2438 int len = sizeof(*lease) + sizeof(u32);
2439 int dnamelen = 0;
2440
2441 dout("lease_send_msg inode %p dentry %p %s to mds%d\n",
2442 inode, dentry, ceph_lease_op_name(action), session->s_mds);
2443 dnamelen = dentry->d_name.len;
2444 len += dnamelen;
2445
2446 msg = ceph_msg_new(CEPH_MSG_CLIENT_LEASE, len, 0, 0, NULL);
2447 if (IS_ERR(msg))
2448 return;
2449 lease = msg->front.iov_base;
2450 lease->action = action;
2451 lease->mask = cpu_to_le16(CEPH_LOCK_DN);
2452 lease->ino = cpu_to_le64(ceph_vino(inode).ino);
2453 lease->first = lease->last = cpu_to_le64(ceph_vino(inode).snap);
2454 lease->seq = cpu_to_le32(seq);
2455 put_unaligned_le32(dnamelen, lease + 1);
2456 memcpy((void *)(lease + 1) + 4, dentry->d_name.name, dnamelen);
2457
2458 /*
2459 * if this is a preemptive lease RELEASE, no need to
2460 * flush request stream, since the actual request will
2461 * soon follow.
2462 */
2463 msg->more_to_follow = (action == CEPH_MDS_LEASE_RELEASE);
2464
2465 ceph_con_send(&session->s_con, msg);
2466}
2467
2468/*
2469 * Preemptively release a lease we expect to invalidate anyway.
2470 * Pass @inode always, @dentry is optional.
2471 */
2472void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, struct inode *inode,
2473 struct dentry *dentry, int mask)
2474{
2475 struct ceph_dentry_info *di;
2476 struct ceph_mds_session *session;
2477 u32 seq;
2478
2479 BUG_ON(inode == NULL);
2480 BUG_ON(dentry == NULL);
2481 BUG_ON(mask != CEPH_LOCK_DN);
2482
2483 /* is dentry lease valid? */
2484 spin_lock(&dentry->d_lock);
2485 di = ceph_dentry(dentry);
2486 if (!di || !di->lease_session ||
2487 di->lease_session->s_mds < 0 ||
2488 di->lease_gen != di->lease_session->s_cap_gen ||
2489 !time_before(jiffies, dentry->d_time)) {
2490 dout("lease_release inode %p dentry %p -- "
2491 "no lease on %d\n",
2492 inode, dentry, mask);
2493 spin_unlock(&dentry->d_lock);
2494 return;
2495 }
2496
2497 /* we do have a lease on this dentry; note mds and seq */
2498 session = ceph_get_mds_session(di->lease_session);
2499 seq = di->lease_seq;
2500 __ceph_mdsc_drop_dentry_lease(dentry);
2501 spin_unlock(&dentry->d_lock);
2502
2503 dout("lease_release inode %p dentry %p mask %d to mds%d\n",
2504 inode, dentry, mask, session->s_mds);
2505 ceph_mdsc_lease_send_msg(session, inode, dentry,
2506 CEPH_MDS_LEASE_RELEASE, seq);
2507 ceph_put_mds_session(session);
2508}
2509
2510/*
2511 * drop all leases (and dentry refs) in preparation for umount
2512 */
2513static void drop_leases(struct ceph_mds_client *mdsc)
2514{
2515 int i;
2516
2517 dout("drop_leases\n");
2518 mutex_lock(&mdsc->mutex);
2519 for (i = 0; i < mdsc->max_sessions; i++) {
2520 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2521 if (!s)
2522 continue;
2523 mutex_unlock(&mdsc->mutex);
2524 mutex_lock(&s->s_mutex);
2525 mutex_unlock(&s->s_mutex);
2526 ceph_put_mds_session(s);
2527 mutex_lock(&mdsc->mutex);
2528 }
2529 mutex_unlock(&mdsc->mutex);
2530}
2531
2532
2533
2534/*
2535 * delayed work -- periodically trim expired leases, renew caps with mds
2536 */
2537static void schedule_delayed(struct ceph_mds_client *mdsc)
2538{
2539 int delay = 5;
2540 unsigned hz = round_jiffies_relative(HZ * delay);
2541 schedule_delayed_work(&mdsc->delayed_work, hz);
2542}
2543
2544static void delayed_work(struct work_struct *work)
2545{
2546 int i;
2547 struct ceph_mds_client *mdsc =
2548 container_of(work, struct ceph_mds_client, delayed_work.work);
2549 int renew_interval;
2550 int renew_caps;
2551
2552 dout("mdsc delayed_work\n");
2553 ceph_check_delayed_caps(mdsc);
2554
2555 mutex_lock(&mdsc->mutex);
2556 renew_interval = mdsc->mdsmap->m_session_timeout >> 2;
2557 renew_caps = time_after_eq(jiffies, HZ*renew_interval +
2558 mdsc->last_renew_caps);
2559 if (renew_caps)
2560 mdsc->last_renew_caps = jiffies;
2561
2562 for (i = 0; i < mdsc->max_sessions; i++) {
2563 struct ceph_mds_session *s = __ceph_lookup_mds_session(mdsc, i);
2564 if (s == NULL)
2565 continue;
2566 if (s->s_state == CEPH_MDS_SESSION_CLOSING) {
2567 dout("resending session close request for mds%d\n",
2568 s->s_mds);
2569 request_close_session(mdsc, s);
2570 ceph_put_mds_session(s);
2571 continue;
2572 }
2573 if (s->s_ttl && time_after(jiffies, s->s_ttl)) {
2574 if (s->s_state == CEPH_MDS_SESSION_OPEN) {
2575 s->s_state = CEPH_MDS_SESSION_HUNG;
2576 pr_info("mds%d hung\n", s->s_mds);
2577 }
2578 }
2579 if (s->s_state < CEPH_MDS_SESSION_OPEN) {
2580 /* this mds is failed or recovering, just wait */
2581 ceph_put_mds_session(s);
2582 continue;
2583 }
2584 mutex_unlock(&mdsc->mutex);
2585
2586 mutex_lock(&s->s_mutex);
2587 if (renew_caps)
2588 send_renew_caps(mdsc, s);
2589 else
2590 ceph_con_keepalive(&s->s_con);
2591 add_cap_releases(mdsc, s, -1);
2592 send_cap_releases(mdsc, s);
2593 mutex_unlock(&s->s_mutex);
2594 ceph_put_mds_session(s);
2595
2596 mutex_lock(&mdsc->mutex);
2597 }
2598 mutex_unlock(&mdsc->mutex);
2599
2600 schedule_delayed(mdsc);
2601}
2602
2603
2604int ceph_mdsc_init(struct ceph_mds_client *mdsc, struct ceph_client *client)
2605{
2606 mdsc->client = client;
2607 mutex_init(&mdsc->mutex);
2608 mdsc->mdsmap = kzalloc(sizeof(*mdsc->mdsmap), GFP_NOFS);
2609 init_completion(&mdsc->safe_umount_waiters);
2610 init_completion(&mdsc->session_close_waiters);
2611 INIT_LIST_HEAD(&mdsc->waiting_for_map);
2612 mdsc->sessions = NULL;
2613 mdsc->max_sessions = 0;
2614 mdsc->stopping = 0;
2615 init_rwsem(&mdsc->snap_rwsem);
2616 mdsc->snap_realms = RB_ROOT;
2617 INIT_LIST_HEAD(&mdsc->snap_empty);
2618 spin_lock_init(&mdsc->snap_empty_lock);
2619 mdsc->last_tid = 0;
2620 mdsc->request_tree = RB_ROOT;
2621 INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
2622 mdsc->last_renew_caps = jiffies;
2623 INIT_LIST_HEAD(&mdsc->cap_delay_list);
2624 spin_lock_init(&mdsc->cap_delay_lock);
2625 INIT_LIST_HEAD(&mdsc->snap_flush_list);
2626 spin_lock_init(&mdsc->snap_flush_lock);
2627 mdsc->cap_flush_seq = 0;
2628 INIT_LIST_HEAD(&mdsc->cap_dirty);
2629 mdsc->num_cap_flushing = 0;
2630 spin_lock_init(&mdsc->cap_dirty_lock);
2631 init_waitqueue_head(&mdsc->cap_flushing_wq);
2632 spin_lock_init(&mdsc->dentry_lru_lock);
2633 INIT_LIST_HEAD(&mdsc->dentry_lru);
2634 return 0;
2635}
2636
2637/*
2638 * Wait for safe replies on open mds requests. If we time out, drop
2639 * all requests from the tree to avoid dangling dentry refs.
2640 */
2641static void wait_requests(struct ceph_mds_client *mdsc)
2642{
2643 struct ceph_mds_request *req;
2644 struct ceph_client *client = mdsc->client;
2645
2646 mutex_lock(&mdsc->mutex);
2647 if (__get_oldest_req(mdsc)) {
2648 mutex_unlock(&mdsc->mutex);
2649
2650 dout("wait_requests waiting for requests\n");
2651 wait_for_completion_timeout(&mdsc->safe_umount_waiters,
2652 client->mount_args->mount_timeout * HZ);
2653
2654 /* tear down remaining requests */
2655 mutex_lock(&mdsc->mutex);
2656 while ((req = __get_oldest_req(mdsc))) {
2657 dout("wait_requests timed out on tid %llu\n",
2658 req->r_tid);
2659 __unregister_request(mdsc, req);
2660 }
2661 }
2662 mutex_unlock(&mdsc->mutex);
2663 dout("wait_requests done\n");
2664}
2665
2666/*
2667 * called before mount is ro, and before dentries are torn down.
2668 * (hmm, does this still race with new lookups?)
2669 */
2670void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc)
2671{
2672 dout("pre_umount\n");
2673 mdsc->stopping = 1;
2674
2675 drop_leases(mdsc);
2676 ceph_flush_dirty_caps(mdsc);
2677 wait_requests(mdsc);
2678}
2679
2680/*
2681 * wait for all write mds requests to flush.
2682 */
2683static void wait_unsafe_requests(struct ceph_mds_client *mdsc, u64 want_tid)
2684{
2685 struct ceph_mds_request *req = NULL;
2686 struct rb_node *n;
2687
2688 mutex_lock(&mdsc->mutex);
2689 dout("wait_unsafe_requests want %lld\n", want_tid);
2690 req = __get_oldest_req(mdsc);
2691 while (req && req->r_tid <= want_tid) {
2692 if ((req->r_op & CEPH_MDS_OP_WRITE)) {
2693 /* write op */
2694 ceph_mdsc_get_request(req);
2695 mutex_unlock(&mdsc->mutex);
2696 dout("wait_unsafe_requests wait on %llu (want %llu)\n",
2697 req->r_tid, want_tid);
2698 wait_for_completion(&req->r_safe_completion);
2699 mutex_lock(&mdsc->mutex);
2700 n = rb_next(&req->r_node);
2701 ceph_mdsc_put_request(req);
2702 } else {
2703 n = rb_next(&req->r_node);
2704 }
2705 if (!n)
2706 break;
2707 req = rb_entry(n, struct ceph_mds_request, r_node);
2708 }
2709 mutex_unlock(&mdsc->mutex);
2710 dout("wait_unsafe_requests done\n");
2711}
2712
2713void ceph_mdsc_sync(struct ceph_mds_client *mdsc)
2714{
2715 u64 want_tid, want_flush;
2716
2717 dout("sync\n");
2718 mutex_lock(&mdsc->mutex);
2719 want_tid = mdsc->last_tid;
2720 want_flush = mdsc->cap_flush_seq;
2721 mutex_unlock(&mdsc->mutex);
2722 dout("sync want tid %lld flush_seq %lld\n", want_tid, want_flush);
2723
2724 ceph_flush_dirty_caps(mdsc);
2725
2726 wait_unsafe_requests(mdsc, want_tid);
2727 wait_event(mdsc->cap_flushing_wq, check_cap_flush(mdsc, want_flush));
2728}
2729
2730
2731/*
2732 * called after sb is ro.
2733 */
2734void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
2735{
2736 struct ceph_mds_session *session;
2737 int i;
2738 int n;
2739 struct ceph_client *client = mdsc->client;
2740 unsigned long started, timeout = client->mount_args->mount_timeout * HZ;
2741
2742 dout("close_sessions\n");
2743
2744 mutex_lock(&mdsc->mutex);
2745
2746 /* close sessions */
2747 started = jiffies;
2748 while (time_before(jiffies, started + timeout)) {
2749 dout("closing sessions\n");
2750 n = 0;
2751 for (i = 0; i < mdsc->max_sessions; i++) {
2752 session = __ceph_lookup_mds_session(mdsc, i);
2753 if (!session)
2754 continue;
2755 mutex_unlock(&mdsc->mutex);
2756 mutex_lock(&session->s_mutex);
2757 __close_session(mdsc, session);
2758 mutex_unlock(&session->s_mutex);
2759 ceph_put_mds_session(session);
2760 mutex_lock(&mdsc->mutex);
2761 n++;
2762 }
2763 if (n == 0)
2764 break;
2765
2766 if (client->mount_state == CEPH_MOUNT_SHUTDOWN)
2767 break;
2768
2769 dout("waiting for sessions to close\n");
2770 mutex_unlock(&mdsc->mutex);
2771 wait_for_completion_timeout(&mdsc->session_close_waiters,
2772 timeout);
2773 mutex_lock(&mdsc->mutex);
2774 }
2775
2776 /* tear down remaining sessions */
2777 for (i = 0; i < mdsc->max_sessions; i++) {
2778 if (mdsc->sessions[i]) {
2779 session = get_session(mdsc->sessions[i]);
2780 __unregister_session(mdsc, session);
2781 mutex_unlock(&mdsc->mutex);
2782 mutex_lock(&session->s_mutex);
2783 remove_session_caps(session);
2784 mutex_unlock(&session->s_mutex);
2785 ceph_put_mds_session(session);
2786 mutex_lock(&mdsc->mutex);
2787 }
2788 }
2789
2790 WARN_ON(!list_empty(&mdsc->cap_delay_list));
2791
2792 mutex_unlock(&mdsc->mutex);
2793
2794 ceph_cleanup_empty_realms(mdsc);
2795
2796 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
2797
2798 dout("stopped\n");
2799}
2800
2801void ceph_mdsc_stop(struct ceph_mds_client *mdsc)
2802{
2803 dout("stop\n");
2804 cancel_delayed_work_sync(&mdsc->delayed_work); /* cancel timer */
2805 if (mdsc->mdsmap)
2806 ceph_mdsmap_destroy(mdsc->mdsmap);
2807 kfree(mdsc->sessions);
2808}
2809
2810
2811/*
2812 * handle mds map update.
2813 */
2814void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, struct ceph_msg *msg)
2815{
2816 u32 epoch;
2817 u32 maplen;
2818 void *p = msg->front.iov_base;
2819 void *end = p + msg->front.iov_len;
2820 struct ceph_mdsmap *newmap, *oldmap;
2821 struct ceph_fsid fsid;
2822 int err = -EINVAL;
2823
2824 ceph_decode_need(&p, end, sizeof(fsid)+2*sizeof(u32), bad);
2825 ceph_decode_copy(&p, &fsid, sizeof(fsid));
2826 if (ceph_check_fsid(mdsc->client, &fsid) < 0)
2827 return;
2828 epoch = ceph_decode_32(&p);
2829 maplen = ceph_decode_32(&p);
2830 dout("handle_map epoch %u len %d\n", epoch, (int)maplen);
2831
2832 /* do we need it? */
2833 ceph_monc_got_mdsmap(&mdsc->client->monc, epoch);
2834 mutex_lock(&mdsc->mutex);
2835 if (mdsc->mdsmap && epoch <= mdsc->mdsmap->m_epoch) {
2836 dout("handle_map epoch %u <= our %u\n",
2837 epoch, mdsc->mdsmap->m_epoch);
2838 mutex_unlock(&mdsc->mutex);
2839 return;
2840 }
2841
2842 newmap = ceph_mdsmap_decode(&p, end);
2843 if (IS_ERR(newmap)) {
2844 err = PTR_ERR(newmap);
2845 goto bad_unlock;
2846 }
2847
2848 /* swap into place */
2849 if (mdsc->mdsmap) {
2850 oldmap = mdsc->mdsmap;
2851 mdsc->mdsmap = newmap;
2852 check_new_map(mdsc, newmap, oldmap);
2853 ceph_mdsmap_destroy(oldmap);
2854 } else {
2855 mdsc->mdsmap = newmap; /* first mds map */
2856 }
2857 mdsc->client->sb->s_maxbytes = mdsc->mdsmap->m_max_file_size;
2858
2859 __wake_requests(mdsc, &mdsc->waiting_for_map);
2860
2861 mutex_unlock(&mdsc->mutex);
2862 schedule_delayed(mdsc);
2863 return;
2864
2865bad_unlock:
2866 mutex_unlock(&mdsc->mutex);
2867bad:
2868 pr_err("error decoding mdsmap %d\n", err);
2869 return;
2870}
2871
2872static struct ceph_connection *con_get(struct ceph_connection *con)
2873{
2874 struct ceph_mds_session *s = con->private;
2875
2876 if (get_session(s)) {
2877 dout("mdsc con_get %p ok (%d)\n", s, atomic_read(&s->s_ref));
2878 return con;
2879 }
2880 dout("mdsc con_get %p FAIL\n", s);
2881 return NULL;
2882}
2883
2884static void con_put(struct ceph_connection *con)
2885{
2886 struct ceph_mds_session *s = con->private;
2887
2888 ceph_put_mds_session(s);
2889 dout("mdsc con_put %p (%d)\n", s, atomic_read(&s->s_ref));
2890}
2891
2892/*
2893 * if the client is unresponsive for long enough, the mds will kill
2894 * the session entirely.
2895 */
2896static void peer_reset(struct ceph_connection *con)
2897{
2898 struct ceph_mds_session *s = con->private;
2899
2900 pr_err("mds%d gave us the boot. IMPLEMENT RECONNECT.\n",
2901 s->s_mds);
2902}
2903
2904static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
2905{
2906 struct ceph_mds_session *s = con->private;
2907 struct ceph_mds_client *mdsc = s->s_mdsc;
2908 int type = le16_to_cpu(msg->hdr.type);
2909
2910 mutex_lock(&mdsc->mutex);
2911 if (__verify_registered_session(mdsc, s) < 0) {
2912 mutex_unlock(&mdsc->mutex);
2913 goto out;
2914 }
2915 mutex_unlock(&mdsc->mutex);
2916
2917 switch (type) {
2918 case CEPH_MSG_MDS_MAP:
2919 ceph_mdsc_handle_map(mdsc, msg);
2920 break;
2921 case CEPH_MSG_CLIENT_SESSION:
2922 handle_session(s, msg);
2923 break;
2924 case CEPH_MSG_CLIENT_REPLY:
2925 handle_reply(s, msg);
2926 break;
2927 case CEPH_MSG_CLIENT_REQUEST_FORWARD:
2928 handle_forward(mdsc, s, msg);
2929 break;
2930 case CEPH_MSG_CLIENT_CAPS:
2931 ceph_handle_caps(s, msg);
2932 break;
2933 case CEPH_MSG_CLIENT_SNAP:
2934 ceph_handle_snap(mdsc, s, msg);
2935 break;
2936 case CEPH_MSG_CLIENT_LEASE:
2937 handle_lease(mdsc, s, msg);
2938 break;
2939
2940 default:
2941 pr_err("received unknown message type %d %s\n", type,
2942 ceph_msg_type_name(type));
2943 }
2944out:
2945 ceph_msg_put(msg);
2946}
2947
2948/*
2949 * authentication
2950 */
2951static int get_authorizer(struct ceph_connection *con,
2952 void **buf, int *len, int *proto,
2953 void **reply_buf, int *reply_len, int force_new)
2954{
2955 struct ceph_mds_session *s = con->private;
2956 struct ceph_mds_client *mdsc = s->s_mdsc;
2957 struct ceph_auth_client *ac = mdsc->client->monc.auth;
2958 int ret = 0;
2959
2960 if (force_new && s->s_authorizer) {
2961 ac->ops->destroy_authorizer(ac, s->s_authorizer);
2962 s->s_authorizer = NULL;
2963 }
2964 if (s->s_authorizer == NULL) {
2965 if (ac->ops->create_authorizer) {
2966 ret = ac->ops->create_authorizer(
2967 ac, CEPH_ENTITY_TYPE_MDS,
2968 &s->s_authorizer,
2969 &s->s_authorizer_buf,
2970 &s->s_authorizer_buf_len,
2971 &s->s_authorizer_reply_buf,
2972 &s->s_authorizer_reply_buf_len);
2973 if (ret)
2974 return ret;
2975 }
2976 }
2977
2978 *proto = ac->protocol;
2979 *buf = s->s_authorizer_buf;
2980 *len = s->s_authorizer_buf_len;
2981 *reply_buf = s->s_authorizer_reply_buf;
2982 *reply_len = s->s_authorizer_reply_buf_len;
2983 return 0;
2984}
2985
2986
2987static int verify_authorizer_reply(struct ceph_connection *con, int len)
2988{
2989 struct ceph_mds_session *s = con->private;
2990 struct ceph_mds_client *mdsc = s->s_mdsc;
2991 struct ceph_auth_client *ac = mdsc->client->monc.auth;
2992
2993 return ac->ops->verify_authorizer_reply(ac, s->s_authorizer, len);
2994}
2995
2996static int invalidate_authorizer(struct ceph_connection *con)
2997{
2998 struct ceph_mds_session *s = con->private;
2999 struct ceph_mds_client *mdsc = s->s_mdsc;
3000 struct ceph_auth_client *ac = mdsc->client->monc.auth;
3001
3002 if (ac->ops->invalidate_authorizer)
3003 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
3004
3005 return ceph_monc_validate_auth(&mdsc->client->monc);
3006}
3007
3008const static struct ceph_connection_operations mds_con_ops = {
3009 .get = con_get,
3010 .put = con_put,
3011 .dispatch = dispatch,
3012 .get_authorizer = get_authorizer,
3013 .verify_authorizer_reply = verify_authorizer_reply,
3014 .invalidate_authorizer = invalidate_authorizer,
3015 .peer_reset = peer_reset,
3016};
3017
3018
3019
3020
3021/* eof */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-23 12:36:04 -0500