blob: e6e954cac6b9303e8fda527f05107f43955a4fd4 [file] [log] [blame]
Sage Weilba75bb92009-10-06 11:31:11 -07001#include "ceph_debug.h"
2
3#include <linux/types.h>
4#include <linux/random.h>
5#include <linux/sched.h>
6
7#include "mon_client.h"
8#include "super.h"
9#include "decode.h"
10
11/*
12 * Interact with Ceph monitor cluster. Handle requests for new map
13 * versions, and periodically resend as needed. Also implement
14 * statfs() and umount().
15 *
16 * A small cluster of Ceph "monitors" are responsible for managing critical
17 * cluster configuration and state information. An odd number (e.g., 3, 5)
18 * of cmon daemons use a modified version of the Paxos part-time parliament
19 * algorithm to manage the MDS map (mds cluster membership), OSD map, and
20 * list of clients who have mounted the file system.
21 *
22 * We maintain an open, active session with a monitor at all times in order to
23 * receive timely MDSMap updates. We periodically send a keepalive byte on the
24 * TCP socket to ensure we detect a failure. If the connection does break, we
25 * randomly hunt for a new monitor. Once the connection is reestablished, we
26 * resend any outstanding requests.
27 */
28
29const static struct ceph_connection_operations mon_con_ops;
30
31/*
32 * Decode a monmap blob (e.g., during mount).
33 */
34struct ceph_monmap *ceph_monmap_decode(void *p, void *end)
35{
36 struct ceph_monmap *m = NULL;
37 int i, err = -EINVAL;
38 struct ceph_fsid fsid;
39 u32 epoch, num_mon;
40 u16 version;
41
42 dout("monmap_decode %p %p len %d\n", p, end, (int)(end-p));
43
44 ceph_decode_16_safe(&p, end, version, bad);
45
46 ceph_decode_need(&p, end, sizeof(fsid) + 2*sizeof(u32), bad);
47 ceph_decode_copy(&p, &fsid, sizeof(fsid));
Sage Weilc89136e2009-10-14 09:59:09 -070048 epoch = ceph_decode_32(&p);
Sage Weilba75bb92009-10-06 11:31:11 -070049
Sage Weilc89136e2009-10-14 09:59:09 -070050 num_mon = ceph_decode_32(&p);
Sage Weilba75bb92009-10-06 11:31:11 -070051 ceph_decode_need(&p, end, num_mon*sizeof(m->mon_inst[0]), bad);
52
53 if (num_mon >= CEPH_MAX_MON)
54 goto bad;
55 m = kmalloc(sizeof(*m) + sizeof(m->mon_inst[0])*num_mon, GFP_NOFS);
56 if (m == NULL)
57 return ERR_PTR(-ENOMEM);
58 m->fsid = fsid;
59 m->epoch = epoch;
60 m->num_mon = num_mon;
61 ceph_decode_copy(&p, m->mon_inst, num_mon*sizeof(m->mon_inst[0]));
62
Sage Weilba75bb92009-10-06 11:31:11 -070063 dout("monmap_decode epoch %d, num_mon %d\n", m->epoch,
64 m->num_mon);
65 for (i = 0; i < m->num_mon; i++)
66 dout("monmap_decode mon%d is %s\n", i,
67 pr_addr(&m->mon_inst[i].addr.in_addr));
68 return m;
69
70bad:
71 dout("monmap_decode failed with %d\n", err);
72 kfree(m);
73 return ERR_PTR(err);
74}
75
76/*
77 * return true if *addr is included in the monmap.
78 */
79int ceph_monmap_contains(struct ceph_monmap *m, struct ceph_entity_addr *addr)
80{
81 int i;
82
83 for (i = 0; i < m->num_mon; i++)
84 if (ceph_entity_addr_equal(addr, &m->mon_inst[i].addr))
85 return 1;
86 return 0;
87}
88
89/*
90 * Close monitor session, if any.
91 */
92static void __close_session(struct ceph_mon_client *monc)
93{
94 if (monc->con) {
95 dout("__close_session closing mon%d\n", monc->cur_mon);
96 ceph_con_close(monc->con);
97 monc->cur_mon = -1;
98 }
99}
100
101/*
102 * Open a session with a (new) monitor.
103 */
104static int __open_session(struct ceph_mon_client *monc)
105{
106 char r;
107
108 if (monc->cur_mon < 0) {
109 get_random_bytes(&r, 1);
110 monc->cur_mon = r % monc->monmap->num_mon;
111 dout("open_session num=%d r=%d -> mon%d\n",
112 monc->monmap->num_mon, r, monc->cur_mon);
113 monc->sub_sent = 0;
114 monc->sub_renew_after = jiffies; /* i.e., expired */
115 monc->want_next_osdmap = !!monc->want_next_osdmap;
116
117 dout("open_session mon%d opening\n", monc->cur_mon);
118 monc->con->peer_name.type = CEPH_ENTITY_TYPE_MON;
119 monc->con->peer_name.num = cpu_to_le64(monc->cur_mon);
120 ceph_con_open(monc->con,
121 &monc->monmap->mon_inst[monc->cur_mon].addr);
122 } else {
123 dout("open_session mon%d already open\n", monc->cur_mon);
124 }
125 return 0;
126}
127
128static bool __sub_expired(struct ceph_mon_client *monc)
129{
130 return time_after_eq(jiffies, monc->sub_renew_after);
131}
132
133/*
134 * Reschedule delayed work timer.
135 */
136static void __schedule_delayed(struct ceph_mon_client *monc)
137{
138 unsigned delay;
139
140 if (monc->cur_mon < 0 || monc->want_mount || __sub_expired(monc))
141 delay = 10 * HZ;
142 else
143 delay = 20 * HZ;
144 dout("__schedule_delayed after %u\n", delay);
145 schedule_delayed_work(&monc->delayed_work, delay);
146}
147
148/*
149 * Send subscribe request for mdsmap and/or osdmap.
150 */
151static void __send_subscribe(struct ceph_mon_client *monc)
152{
153 dout("__send_subscribe sub_sent=%u exp=%u want_osd=%d\n",
154 (unsigned)monc->sub_sent, __sub_expired(monc),
155 monc->want_next_osdmap);
156 if ((__sub_expired(monc) && !monc->sub_sent) ||
157 monc->want_next_osdmap == 1) {
158 struct ceph_msg *msg;
159 struct ceph_mon_subscribe_item *i;
160 void *p, *end;
161
162 msg = ceph_msg_new(CEPH_MSG_MON_SUBSCRIBE, 64, 0, 0, NULL);
163 if (!msg)
164 return;
165
166 p = msg->front.iov_base;
167 end = p + msg->front.iov_len;
168
169 dout("__send_subscribe to 'mdsmap' %u+\n",
170 (unsigned)monc->have_mdsmap);
171 if (monc->want_next_osdmap) {
172 dout("__send_subscribe to 'osdmap' %u\n",
173 (unsigned)monc->have_osdmap);
174 ceph_encode_32(&p, 2);
175 ceph_encode_string(&p, end, "osdmap", 6);
176 i = p;
177 i->have = cpu_to_le64(monc->have_osdmap);
178 i->onetime = 1;
179 p += sizeof(*i);
180 monc->want_next_osdmap = 2; /* requested */
181 } else {
182 ceph_encode_32(&p, 1);
183 }
184 ceph_encode_string(&p, end, "mdsmap", 6);
185 i = p;
186 i->have = cpu_to_le64(monc->have_mdsmap);
187 i->onetime = 0;
188 p += sizeof(*i);
189
190 msg->front.iov_len = p - msg->front.iov_base;
191 msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
192 ceph_con_send(monc->con, msg);
193
194 monc->sub_sent = jiffies | 1; /* never 0 */
195 }
196}
197
198static void handle_subscribe_ack(struct ceph_mon_client *monc,
199 struct ceph_msg *msg)
200{
201 unsigned seconds;
Sage Weil07bd10f2009-10-14 17:26:40 -0700202 struct ceph_mon_subscribe_ack *h = msg->front.iov_base;
Sage Weilba75bb92009-10-06 11:31:11 -0700203
Sage Weil07bd10f2009-10-14 17:26:40 -0700204 if (msg->front.iov_len < sizeof(*h))
205 goto bad;
206 seconds = le32_to_cpu(h->duration);
207
Sage Weilba75bb92009-10-06 11:31:11 -0700208 mutex_lock(&monc->mutex);
209 if (monc->hunting) {
210 pr_info("mon%d %s session established\n",
211 monc->cur_mon, pr_addr(&monc->con->peer_addr.in_addr));
212 monc->hunting = false;
213 }
214 dout("handle_subscribe_ack after %d seconds\n", seconds);
Sage Weil0656d112009-10-08 10:25:46 -0700215 monc->sub_renew_after = monc->sub_sent + (seconds >> 1)*HZ - 1;
Sage Weilba75bb92009-10-06 11:31:11 -0700216 monc->sub_sent = 0;
217 mutex_unlock(&monc->mutex);
218 return;
219bad:
220 pr_err("got corrupt subscribe-ack msg\n");
221}
222
223/*
224 * Keep track of which maps we have
225 */
226int ceph_monc_got_mdsmap(struct ceph_mon_client *monc, u32 got)
227{
228 mutex_lock(&monc->mutex);
229 monc->have_mdsmap = got;
230 mutex_unlock(&monc->mutex);
231 return 0;
232}
233
234int ceph_monc_got_osdmap(struct ceph_mon_client *monc, u32 got)
235{
236 mutex_lock(&monc->mutex);
237 monc->have_osdmap = got;
238 monc->want_next_osdmap = 0;
239 mutex_unlock(&monc->mutex);
240 return 0;
241}
242
243/*
244 * Register interest in the next osdmap
245 */
246void ceph_monc_request_next_osdmap(struct ceph_mon_client *monc)
247{
248 dout("request_next_osdmap have %u\n", monc->have_osdmap);
249 mutex_lock(&monc->mutex);
250 if (!monc->want_next_osdmap)
251 monc->want_next_osdmap = 1;
252 if (monc->want_next_osdmap < 2)
253 __send_subscribe(monc);
254 mutex_unlock(&monc->mutex);
255}
256
257
258/*
259 * mount
260 */
261static void __request_mount(struct ceph_mon_client *monc)
262{
263 struct ceph_msg *msg;
264 struct ceph_client_mount *h;
265 int err;
266
267 dout("__request_mount\n");
268 err = __open_session(monc);
269 if (err)
270 return;
271 msg = ceph_msg_new(CEPH_MSG_CLIENT_MOUNT, sizeof(*h), 0, 0, NULL);
272 if (IS_ERR(msg))
273 return;
274 h = msg->front.iov_base;
Sage Weil13e38c82009-10-09 16:36:34 -0700275 h->monhdr.have_version = 0;
276 h->monhdr.session_mon = cpu_to_le16(-1);
277 h->monhdr.session_mon_tid = 0;
Sage Weilba75bb92009-10-06 11:31:11 -0700278 ceph_con_send(monc->con, msg);
279}
280
281int ceph_monc_request_mount(struct ceph_mon_client *monc)
282{
283 if (!monc->con) {
284 monc->con = kmalloc(sizeof(*monc->con), GFP_KERNEL);
285 if (!monc->con)
286 return -ENOMEM;
287 ceph_con_init(monc->client->msgr, monc->con);
288 monc->con->private = monc;
289 monc->con->ops = &mon_con_ops;
290 }
291
292 mutex_lock(&monc->mutex);
293 __request_mount(monc);
294 __schedule_delayed(monc);
295 mutex_unlock(&monc->mutex);
296 return 0;
297}
298
299/*
300 * The monitor responds with mount ack indicate mount success. The
301 * included client ticket allows the client to talk to MDSs and OSDs.
302 */
303static void handle_mount_ack(struct ceph_mon_client *monc, struct ceph_msg *msg)
304{
305 struct ceph_client *client = monc->client;
306 struct ceph_monmap *monmap = NULL, *old = monc->monmap;
307 void *p, *end;
308 s32 result;
309 u32 len;
310 s64 cnum;
311 int err = -EINVAL;
312
313 if (client->whoami >= 0) {
314 dout("handle_mount_ack - already mounted\n");
315 return;
316 }
317
318 mutex_lock(&monc->mutex);
319
320 dout("handle_mount_ack\n");
321 p = msg->front.iov_base;
322 end = p + msg->front.iov_len;
323
324 ceph_decode_64_safe(&p, end, cnum, bad);
325 ceph_decode_32_safe(&p, end, result, bad);
326 ceph_decode_32_safe(&p, end, len, bad);
327 if (result) {
328 pr_err("mount denied: %.*s (%d)\n", len, (char *)p,
329 result);
330 err = result;
331 goto out;
332 }
333 p += len;
334
335 ceph_decode_32_safe(&p, end, len, bad);
336 ceph_decode_need(&p, end, len, bad);
337 monmap = ceph_monmap_decode(p, p + len);
338 if (IS_ERR(monmap)) {
339 pr_err("problem decoding monmap, %d\n",
340 (int)PTR_ERR(monmap));
341 err = -EINVAL;
342 goto out;
343 }
344 p += len;
345
346 client->monc.monmap = monmap;
347 kfree(old);
348
349 client->signed_ticket = NULL;
350 client->signed_ticket_len = 0;
351
352 monc->want_mount = false;
353
354 client->whoami = cnum;
355 client->msgr->inst.name.type = CEPH_ENTITY_TYPE_CLIENT;
356 client->msgr->inst.name.num = cpu_to_le64(cnum);
357 pr_info("client%lld fsid " FSID_FORMAT "\n",
358 client->whoami, PR_FSID(&client->monc.monmap->fsid));
359
360 ceph_debugfs_client_init(client);
361 __send_subscribe(monc);
362
363 err = 0;
364 goto out;
365
366bad:
367 pr_err("error decoding mount_ack message\n");
368out:
369 client->mount_err = err;
370 mutex_unlock(&monc->mutex);
371 wake_up(&client->mount_wq);
372}
373
374
375
376
377/*
378 * statfs
379 */
380static void handle_statfs_reply(struct ceph_mon_client *monc,
381 struct ceph_msg *msg)
382{
383 struct ceph_mon_statfs_request *req;
384 struct ceph_mon_statfs_reply *reply = msg->front.iov_base;
385 u64 tid;
386
387 if (msg->front.iov_len != sizeof(*reply))
388 goto bad;
389 tid = le64_to_cpu(reply->tid);
390 dout("handle_statfs_reply %p tid %llu\n", msg, tid);
391
392 mutex_lock(&monc->mutex);
393 req = radix_tree_lookup(&monc->statfs_request_tree, tid);
394 if (req) {
395 *req->buf = reply->st;
396 req->result = 0;
397 }
398 mutex_unlock(&monc->mutex);
399 if (req)
400 complete(&req->completion);
401 return;
402
403bad:
404 pr_err("corrupt statfs reply, no tid\n");
405}
406
407/*
408 * (re)send a statfs request
409 */
410static int send_statfs(struct ceph_mon_client *monc,
411 struct ceph_mon_statfs_request *req)
412{
413 struct ceph_msg *msg;
414 struct ceph_mon_statfs *h;
415 int err;
416
417 dout("send_statfs tid %llu\n", req->tid);
418 err = __open_session(monc);
419 if (err)
420 return err;
421 msg = ceph_msg_new(CEPH_MSG_STATFS, sizeof(*h), 0, 0, NULL);
422 if (IS_ERR(msg))
423 return PTR_ERR(msg);
424 req->request = msg;
425 h = msg->front.iov_base;
Sage Weil13e38c82009-10-09 16:36:34 -0700426 h->monhdr.have_version = 0;
427 h->monhdr.session_mon = cpu_to_le16(-1);
428 h->monhdr.session_mon_tid = 0;
Sage Weilba75bb92009-10-06 11:31:11 -0700429 h->fsid = monc->monmap->fsid;
430 h->tid = cpu_to_le64(req->tid);
431 ceph_con_send(monc->con, msg);
432 return 0;
433}
434
435/*
436 * Do a synchronous statfs().
437 */
438int ceph_monc_do_statfs(struct ceph_mon_client *monc, struct ceph_statfs *buf)
439{
440 struct ceph_mon_statfs_request req;
441 int err;
442
443 req.buf = buf;
444 init_completion(&req.completion);
445
446 /* allocate memory for reply */
447 err = ceph_msgpool_resv(&monc->msgpool_statfs_reply, 1);
448 if (err)
449 return err;
450
451 /* register request */
452 mutex_lock(&monc->mutex);
453 req.tid = ++monc->last_tid;
454 req.last_attempt = jiffies;
455 req.delay = BASE_DELAY_INTERVAL;
456 if (radix_tree_insert(&monc->statfs_request_tree, req.tid, &req) < 0) {
457 mutex_unlock(&monc->mutex);
458 pr_err("ENOMEM in do_statfs\n");
459 return -ENOMEM;
460 }
461 monc->num_statfs_requests++;
462 mutex_unlock(&monc->mutex);
463
464 /* send request and wait */
465 err = send_statfs(monc, &req);
466 if (!err)
467 err = wait_for_completion_interruptible(&req.completion);
468
469 mutex_lock(&monc->mutex);
470 radix_tree_delete(&monc->statfs_request_tree, req.tid);
471 monc->num_statfs_requests--;
472 ceph_msgpool_resv(&monc->msgpool_statfs_reply, -1);
473 mutex_unlock(&monc->mutex);
474
475 if (!err)
476 err = req.result;
477 return err;
478}
479
480/*
481 * Resend pending statfs requests.
482 */
483static void __resend_statfs(struct ceph_mon_client *monc)
484{
485 u64 next_tid = 0;
486 int got;
487 int did = 0;
488 struct ceph_mon_statfs_request *req;
489
490 while (1) {
491 got = radix_tree_gang_lookup(&monc->statfs_request_tree,
492 (void **)&req,
493 next_tid, 1);
494 if (got == 0)
495 break;
496 did++;
497 next_tid = req->tid + 1;
498
499 send_statfs(monc, req);
500 }
501}
502
503/*
504 * Delayed work. If we haven't mounted yet, retry. Otherwise,
505 * renew/retry subscription as needed (in case it is timing out, or we
506 * got an ENOMEM). And keep the monitor connection alive.
507 */
508static void delayed_work(struct work_struct *work)
509{
510 struct ceph_mon_client *monc =
511 container_of(work, struct ceph_mon_client, delayed_work.work);
512
513 dout("monc delayed_work\n");
514 mutex_lock(&monc->mutex);
515 if (monc->want_mount) {
516 __request_mount(monc);
517 } else {
Sage Weil0656d112009-10-08 10:25:46 -0700518 if (monc->hunting) {
Sage Weilba75bb92009-10-06 11:31:11 -0700519 __close_session(monc);
520 __open_session(monc); /* continue hunting */
521 } else {
522 ceph_con_keepalive(monc->con);
523 }
524 }
525 __send_subscribe(monc);
526 __schedule_delayed(monc);
527 mutex_unlock(&monc->mutex);
528}
529
530int ceph_monc_init(struct ceph_mon_client *monc, struct ceph_client *cl)
531{
532 int err = 0;
533
534 dout("init\n");
535 memset(monc, 0, sizeof(*monc));
536 monc->client = cl;
537 monc->monmap = NULL;
538 mutex_init(&monc->mutex);
539
540 monc->con = NULL;
541
542 /* msg pools */
543 err = ceph_msgpool_init(&monc->msgpool_mount_ack, 4096, 1, false);
544 if (err < 0)
545 goto out;
Sage Weil07bd10f2009-10-14 17:26:40 -0700546 err = ceph_msgpool_init(&monc->msgpool_subscribe_ack,
547 sizeof(struct ceph_mon_subscribe_ack), 1, false);
Sage Weilba75bb92009-10-06 11:31:11 -0700548 if (err < 0)
549 goto out;
550 err = ceph_msgpool_init(&monc->msgpool_statfs_reply,
551 sizeof(struct ceph_mon_statfs_reply), 0, false);
552 if (err < 0)
553 goto out;
554
555 monc->cur_mon = -1;
556 monc->hunting = false; /* not really */
557 monc->sub_renew_after = jiffies;
558 monc->sub_sent = 0;
559
560 INIT_DELAYED_WORK(&monc->delayed_work, delayed_work);
561 INIT_RADIX_TREE(&monc->statfs_request_tree, GFP_NOFS);
562 monc->num_statfs_requests = 0;
563 monc->last_tid = 0;
564
565 monc->have_mdsmap = 0;
566 monc->have_osdmap = 0;
567 monc->want_next_osdmap = 1;
568 monc->want_mount = true;
569out:
570 return err;
571}
572
573void ceph_monc_stop(struct ceph_mon_client *monc)
574{
575 dout("stop\n");
576 cancel_delayed_work_sync(&monc->delayed_work);
577
578 mutex_lock(&monc->mutex);
579 __close_session(monc);
580 if (monc->con) {
581 monc->con->private = NULL;
582 monc->con->ops->put(monc->con);
583 monc->con = NULL;
584 }
585 mutex_unlock(&monc->mutex);
586
587 ceph_msgpool_destroy(&monc->msgpool_mount_ack);
588 ceph_msgpool_destroy(&monc->msgpool_subscribe_ack);
589 ceph_msgpool_destroy(&monc->msgpool_statfs_reply);
590
591 kfree(monc->monmap);
592}
593
594
595/*
596 * handle incoming message
597 */
598static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
599{
600 struct ceph_mon_client *monc = con->private;
601 int type = le16_to_cpu(msg->hdr.type);
602
603 if (!monc)
604 return;
605
606 switch (type) {
607 case CEPH_MSG_CLIENT_MOUNT_ACK:
608 handle_mount_ack(monc, msg);
609 break;
610
611 case CEPH_MSG_MON_SUBSCRIBE_ACK:
612 handle_subscribe_ack(monc, msg);
613 break;
614
615 case CEPH_MSG_STATFS_REPLY:
616 handle_statfs_reply(monc, msg);
617 break;
618
619 case CEPH_MSG_MDS_MAP:
620 ceph_mdsc_handle_map(&monc->client->mdsc, msg);
621 break;
622
623 case CEPH_MSG_OSD_MAP:
624 ceph_osdc_handle_map(&monc->client->osdc, msg);
625 break;
626
627 default:
628 pr_err("received unknown message type %d %s\n", type,
629 ceph_msg_type_name(type));
630 }
631 ceph_msg_put(msg);
632}
633
634/*
635 * Allocate memory for incoming message
636 */
637static struct ceph_msg *mon_alloc_msg(struct ceph_connection *con,
638 struct ceph_msg_header *hdr)
639{
640 struct ceph_mon_client *monc = con->private;
641 int type = le16_to_cpu(hdr->type);
Sage Weil8f3bc052009-10-14 17:36:07 -0700642 int front = le32_to_cpu(hdr->front_len);
Sage Weilba75bb92009-10-06 11:31:11 -0700643
644 switch (type) {
645 case CEPH_MSG_CLIENT_MOUNT_ACK:
Sage Weil8f3bc052009-10-14 17:36:07 -0700646 return ceph_msgpool_get(&monc->msgpool_mount_ack, front);
Sage Weilba75bb92009-10-06 11:31:11 -0700647 case CEPH_MSG_MON_SUBSCRIBE_ACK:
Sage Weil8f3bc052009-10-14 17:36:07 -0700648 return ceph_msgpool_get(&monc->msgpool_subscribe_ack, front);
Sage Weilba75bb92009-10-06 11:31:11 -0700649 case CEPH_MSG_STATFS_REPLY:
Sage Weil8f3bc052009-10-14 17:36:07 -0700650 return ceph_msgpool_get(&monc->msgpool_statfs_reply, front);
Sage Weilba75bb92009-10-06 11:31:11 -0700651 }
652 return ceph_alloc_msg(con, hdr);
653}
654
655/*
656 * If the monitor connection resets, pick a new monitor and resubmit
657 * any pending requests.
658 */
659static void mon_fault(struct ceph_connection *con)
660{
661 struct ceph_mon_client *monc = con->private;
662
663 if (!monc)
664 return;
665
666 dout("mon_fault\n");
667 mutex_lock(&monc->mutex);
668 if (!con->private)
669 goto out;
670
671 if (monc->con && !monc->hunting)
672 pr_info("mon%d %s session lost, "
673 "hunting for new mon\n", monc->cur_mon,
674 pr_addr(&monc->con->peer_addr.in_addr));
675
676 __close_session(monc);
677 if (!monc->hunting) {
678 /* start hunting */
679 monc->hunting = true;
680 if (__open_session(monc) == 0) {
681 __send_subscribe(monc);
682 __resend_statfs(monc);
683 }
684 } else {
685 /* already hunting, let's wait a bit */
686 __schedule_delayed(monc);
687 }
688out:
689 mutex_unlock(&monc->mutex);
690}
691
692const static struct ceph_connection_operations mon_con_ops = {
693 .get = ceph_con_get,
694 .put = ceph_con_put,
695 .dispatch = dispatch,
696 .fault = mon_fault,
697 .alloc_msg = mon_alloc_msg,
698 .alloc_middle = ceph_alloc_middle,
699};