Merge branch 'oprofile-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / fs / ceph / osd_client.c
1 #include "ceph_debug.h"
2
3 #include <linux/err.h>
4 #include <linux/highmem.h>
5 #include <linux/mm.h>
6 #include <linux/pagemap.h>
7 #include <linux/slab.h>
8 #include <linux/uaccess.h>
9
10 #include "super.h"
11 #include "osd_client.h"
12 #include "messenger.h"
13 #include "decode.h"
14 #include "auth.h"
15
16 #define OSD_OP_FRONT_LEN        4096
17 #define OSD_OPREPLY_FRONT_LEN   512
18
19 const static struct ceph_connection_operations osd_con_ops;
20 static int __kick_requests(struct ceph_osd_client *osdc,
21                           struct ceph_osd *kickosd);
22
23 static void kick_requests(struct ceph_osd_client *osdc, struct ceph_osd *osd);
24
25 /*
26  * Implement client access to distributed object storage cluster.
27  *
28  * All data objects are stored within a cluster/cloud of OSDs, or
29  * "object storage devices."  (Note that Ceph OSDs have _nothing_ to
30  * do with the T10 OSD extensions to SCSI.)  Ceph OSDs are simply
31  * remote daemons serving up and coordinating consistent and safe
32  * access to storage.
33  *
34  * Cluster membership and the mapping of data objects onto storage devices
35  * are described by the osd map.
36  *
37  * We keep track of pending OSD requests (read, write), resubmit
38  * requests to different OSDs when the cluster topology/data layout
39  * change, or retry the affected requests when the communications
40  * channel with an OSD is reset.
41  */
42
43 /*
44  * calculate the mapping of a file extent onto an object, and fill out the
45  * request accordingly.  shorten extent as necessary if it crosses an
46  * object boundary.
47  *
48  * fill osd op in request message.
49  */
50 static void calc_layout(struct ceph_osd_client *osdc,
51                         struct ceph_vino vino, struct ceph_file_layout *layout,
52                         u64 off, u64 *plen,
53                         struct ceph_osd_request *req)
54 {
55         struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
56         struct ceph_osd_op *op = (void *)(reqhead + 1);
57         u64 orig_len = *plen;
58         u64 objoff, objlen;    /* extent in object */
59         u64 bno;
60
61         reqhead->snapid = cpu_to_le64(vino.snap);
62
63         /* object extent? */
64         ceph_calc_file_object_mapping(layout, off, plen, &bno,
65                                       &objoff, &objlen);
66         if (*plen < orig_len)
67                 dout(" skipping last %llu, final file extent %llu~%llu\n",
68                      orig_len - *plen, off, *plen);
69
70         sprintf(req->r_oid, "%llx.%08llx", vino.ino, bno);
71         req->r_oid_len = strlen(req->r_oid);
72
73         op->extent.offset = cpu_to_le64(objoff);
74         op->extent.length = cpu_to_le64(objlen);
75         req->r_num_pages = calc_pages_for(off, *plen);
76
77         dout("calc_layout %s (%d) %llu~%llu (%d pages)\n",
78              req->r_oid, req->r_oid_len, objoff, objlen, req->r_num_pages);
79 }
80
81 /*
82  * requests
83  */
84 void ceph_osdc_release_request(struct kref *kref)
85 {
86         struct ceph_osd_request *req = container_of(kref,
87                                                     struct ceph_osd_request,
88                                                     r_kref);
89
90         if (req->r_request)
91                 ceph_msg_put(req->r_request);
92         if (req->r_reply)
93                 ceph_msg_put(req->r_reply);
94         if (req->r_con_filling_msg) {
95                 dout("release_request revoking pages %p from con %p\n",
96                      req->r_pages, req->r_con_filling_msg);
97                 ceph_con_revoke_message(req->r_con_filling_msg,
98                                       req->r_reply);
99                 ceph_con_put(req->r_con_filling_msg);
100         }
101         if (req->r_own_pages)
102                 ceph_release_page_vector(req->r_pages,
103                                          req->r_num_pages);
104         ceph_put_snap_context(req->r_snapc);
105         if (req->r_mempool)
106                 mempool_free(req, req->r_osdc->req_mempool);
107         else
108                 kfree(req);
109 }
110
111 /*
112  * build new request AND message, calculate layout, and adjust file
113  * extent as needed.
114  *
115  * if the file was recently truncated, we include information about its
116  * old and new size so that the object can be updated appropriately.  (we
117  * avoid synchronously deleting truncated objects because it's slow.)
118  *
119  * if @do_sync, include a 'startsync' command so that the osd will flush
120  * data quickly.
121  */
122 struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
123                                                struct ceph_file_layout *layout,
124                                                struct ceph_vino vino,
125                                                u64 off, u64 *plen,
126                                                int opcode, int flags,
127                                                struct ceph_snap_context *snapc,
128                                                int do_sync,
129                                                u32 truncate_seq,
130                                                u64 truncate_size,
131                                                struct timespec *mtime,
132                                                bool use_mempool, int num_reply)
133 {
134         struct ceph_osd_request *req;
135         struct ceph_msg *msg;
136         struct ceph_osd_request_head *head;
137         struct ceph_osd_op *op;
138         void *p;
139         int num_op = 1 + do_sync;
140         size_t msg_size = sizeof(*head) + num_op*sizeof(*op);
141         int i;
142
143         if (use_mempool) {
144                 req = mempool_alloc(osdc->req_mempool, GFP_NOFS);
145                 memset(req, 0, sizeof(*req));
146         } else {
147                 req = kzalloc(sizeof(*req), GFP_NOFS);
148         }
149         if (req == NULL)
150                 return ERR_PTR(-ENOMEM);
151
152         req->r_osdc = osdc;
153         req->r_mempool = use_mempool;
154         kref_init(&req->r_kref);
155         init_completion(&req->r_completion);
156         init_completion(&req->r_safe_completion);
157         INIT_LIST_HEAD(&req->r_unsafe_item);
158         req->r_flags = flags;
159
160         WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
161
162         /* create reply message */
163         if (use_mempool)
164                 msg = ceph_msgpool_get(&osdc->msgpool_op_reply, 0);
165         else
166                 msg = ceph_msg_new(CEPH_MSG_OSD_OPREPLY,
167                                    OSD_OPREPLY_FRONT_LEN, 0, 0, NULL);
168         if (IS_ERR(msg)) {
169                 ceph_osdc_put_request(req);
170                 return ERR_PTR(PTR_ERR(msg));
171         }
172         req->r_reply = msg;
173
174         /* create request message; allow space for oid */
175         msg_size += 40;
176         if (snapc)
177                 msg_size += sizeof(u64) * snapc->num_snaps;
178         if (use_mempool)
179                 msg = ceph_msgpool_get(&osdc->msgpool_op, 0);
180         else
181                 msg = ceph_msg_new(CEPH_MSG_OSD_OP, msg_size, 0, 0, NULL);
182         if (IS_ERR(msg)) {
183                 ceph_osdc_put_request(req);
184                 return ERR_PTR(PTR_ERR(msg));
185         }
186         msg->hdr.type = cpu_to_le16(CEPH_MSG_OSD_OP);
187         memset(msg->front.iov_base, 0, msg->front.iov_len);
188         head = msg->front.iov_base;
189         op = (void *)(head + 1);
190         p = (void *)(op + num_op);
191
192         req->r_request = msg;
193         req->r_snapc = ceph_get_snap_context(snapc);
194
195         head->client_inc = cpu_to_le32(1); /* always, for now. */
196         head->flags = cpu_to_le32(flags);
197         if (flags & CEPH_OSD_FLAG_WRITE)
198                 ceph_encode_timespec(&head->mtime, mtime);
199         head->num_ops = cpu_to_le16(num_op);
200         op->op = cpu_to_le16(opcode);
201
202         /* calculate max write size */
203         calc_layout(osdc, vino, layout, off, plen, req);
204         req->r_file_layout = *layout;  /* keep a copy */
205
206         if (flags & CEPH_OSD_FLAG_WRITE) {
207                 req->r_request->hdr.data_off = cpu_to_le16(off);
208                 req->r_request->hdr.data_len = cpu_to_le32(*plen);
209                 op->payload_len = cpu_to_le32(*plen);
210         }
211         op->extent.truncate_size = cpu_to_le64(truncate_size);
212         op->extent.truncate_seq = cpu_to_le32(truncate_seq);
213
214         /* fill in oid */
215         head->object_len = cpu_to_le32(req->r_oid_len);
216         memcpy(p, req->r_oid, req->r_oid_len);
217         p += req->r_oid_len;
218
219         if (do_sync) {
220                 op++;
221                 op->op = cpu_to_le16(CEPH_OSD_OP_STARTSYNC);
222         }
223         if (snapc) {
224                 head->snap_seq = cpu_to_le64(snapc->seq);
225                 head->num_snaps = cpu_to_le32(snapc->num_snaps);
226                 for (i = 0; i < snapc->num_snaps; i++) {
227                         put_unaligned_le64(snapc->snaps[i], p);
228                         p += sizeof(u64);
229                 }
230         }
231
232         BUG_ON(p > msg->front.iov_base + msg->front.iov_len);
233         msg_size = p - msg->front.iov_base;
234         msg->front.iov_len = msg_size;
235         msg->hdr.front_len = cpu_to_le32(msg_size);
236         return req;
237 }
238
239 /*
240  * We keep osd requests in an rbtree, sorted by ->r_tid.
241  */
242 static void __insert_request(struct ceph_osd_client *osdc,
243                              struct ceph_osd_request *new)
244 {
245         struct rb_node **p = &osdc->requests.rb_node;
246         struct rb_node *parent = NULL;
247         struct ceph_osd_request *req = NULL;
248
249         while (*p) {
250                 parent = *p;
251                 req = rb_entry(parent, struct ceph_osd_request, r_node);
252                 if (new->r_tid < req->r_tid)
253                         p = &(*p)->rb_left;
254                 else if (new->r_tid > req->r_tid)
255                         p = &(*p)->rb_right;
256                 else
257                         BUG();
258         }
259
260         rb_link_node(&new->r_node, parent, p);
261         rb_insert_color(&new->r_node, &osdc->requests);
262 }
263
264 static struct ceph_osd_request *__lookup_request(struct ceph_osd_client *osdc,
265                                                  u64 tid)
266 {
267         struct ceph_osd_request *req;
268         struct rb_node *n = osdc->requests.rb_node;
269
270         while (n) {
271                 req = rb_entry(n, struct ceph_osd_request, r_node);
272                 if (tid < req->r_tid)
273                         n = n->rb_left;
274                 else if (tid > req->r_tid)
275                         n = n->rb_right;
276                 else
277                         return req;
278         }
279         return NULL;
280 }
281
282 static struct ceph_osd_request *
283 __lookup_request_ge(struct ceph_osd_client *osdc,
284                     u64 tid)
285 {
286         struct ceph_osd_request *req;
287         struct rb_node *n = osdc->requests.rb_node;
288
289         while (n) {
290                 req = rb_entry(n, struct ceph_osd_request, r_node);
291                 if (tid < req->r_tid) {
292                         if (!n->rb_left)
293                                 return req;
294                         n = n->rb_left;
295                 } else if (tid > req->r_tid) {
296                         n = n->rb_right;
297                 } else {
298                         return req;
299                 }
300         }
301         return NULL;
302 }
303
304
305 /*
306  * If the osd connection drops, we need to resubmit all requests.
307  */
308 static void osd_reset(struct ceph_connection *con)
309 {
310         struct ceph_osd *osd = con->private;
311         struct ceph_osd_client *osdc;
312
313         if (!osd)
314                 return;
315         dout("osd_reset osd%d\n", osd->o_osd);
316         osdc = osd->o_osdc;
317         down_read(&osdc->map_sem);
318         kick_requests(osdc, osd);
319         up_read(&osdc->map_sem);
320 }
321
322 /*
323  * Track open sessions with osds.
324  */
325 static struct ceph_osd *create_osd(struct ceph_osd_client *osdc)
326 {
327         struct ceph_osd *osd;
328
329         osd = kzalloc(sizeof(*osd), GFP_NOFS);
330         if (!osd)
331                 return NULL;
332
333         atomic_set(&osd->o_ref, 1);
334         osd->o_osdc = osdc;
335         INIT_LIST_HEAD(&osd->o_requests);
336         INIT_LIST_HEAD(&osd->o_osd_lru);
337         osd->o_incarnation = 1;
338
339         ceph_con_init(osdc->client->msgr, &osd->o_con);
340         osd->o_con.private = osd;
341         osd->o_con.ops = &osd_con_ops;
342         osd->o_con.peer_name.type = CEPH_ENTITY_TYPE_OSD;
343
344         INIT_LIST_HEAD(&osd->o_keepalive_item);
345         return osd;
346 }
347
348 static struct ceph_osd *get_osd(struct ceph_osd *osd)
349 {
350         if (atomic_inc_not_zero(&osd->o_ref)) {
351                 dout("get_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref)-1,
352                      atomic_read(&osd->o_ref));
353                 return osd;
354         } else {
355                 dout("get_osd %p FAIL\n", osd);
356                 return NULL;
357         }
358 }
359
360 static void put_osd(struct ceph_osd *osd)
361 {
362         dout("put_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref),
363              atomic_read(&osd->o_ref) - 1);
364         if (atomic_dec_and_test(&osd->o_ref))
365                 kfree(osd);
366 }
367
368 /*
369  * remove an osd from our map
370  */
371 static void __remove_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
372 {
373         dout("__remove_osd %p\n", osd);
374         BUG_ON(!list_empty(&osd->o_requests));
375         rb_erase(&osd->o_node, &osdc->osds);
376         list_del_init(&osd->o_osd_lru);
377         ceph_con_close(&osd->o_con);
378         put_osd(osd);
379 }
380
381 static void __move_osd_to_lru(struct ceph_osd_client *osdc,
382                               struct ceph_osd *osd)
383 {
384         dout("__move_osd_to_lru %p\n", osd);
385         BUG_ON(!list_empty(&osd->o_osd_lru));
386         list_add_tail(&osd->o_osd_lru, &osdc->osd_lru);
387         osd->lru_ttl = jiffies + osdc->client->mount_args->osd_idle_ttl * HZ;
388 }
389
390 static void __remove_osd_from_lru(struct ceph_osd *osd)
391 {
392         dout("__remove_osd_from_lru %p\n", osd);
393         if (!list_empty(&osd->o_osd_lru))
394                 list_del_init(&osd->o_osd_lru);
395 }
396
397 static void remove_old_osds(struct ceph_osd_client *osdc, int remove_all)
398 {
399         struct ceph_osd *osd, *nosd;
400
401         dout("__remove_old_osds %p\n", osdc);
402         mutex_lock(&osdc->request_mutex);
403         list_for_each_entry_safe(osd, nosd, &osdc->osd_lru, o_osd_lru) {
404                 if (!remove_all && time_before(jiffies, osd->lru_ttl))
405                         break;
406                 __remove_osd(osdc, osd);
407         }
408         mutex_unlock(&osdc->request_mutex);
409 }
410
411 /*
412  * reset osd connect
413  */
414 static int __reset_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
415 {
416         struct ceph_osd_request *req;
417         int ret = 0;
418
419         dout("__reset_osd %p osd%d\n", osd, osd->o_osd);
420         if (list_empty(&osd->o_requests)) {
421                 __remove_osd(osdc, osd);
422         } else if (memcmp(&osdc->osdmap->osd_addr[osd->o_osd],
423                           &osd->o_con.peer_addr,
424                           sizeof(osd->o_con.peer_addr)) == 0 &&
425                    !ceph_con_opened(&osd->o_con)) {
426                 dout(" osd addr hasn't changed and connection never opened,"
427                      " letting msgr retry");
428                 /* touch each r_stamp for handle_timeout()'s benfit */
429                 list_for_each_entry(req, &osd->o_requests, r_osd_item)
430                         req->r_stamp = jiffies;
431                 ret = -EAGAIN;
432         } else {
433                 ceph_con_close(&osd->o_con);
434                 ceph_con_open(&osd->o_con, &osdc->osdmap->osd_addr[osd->o_osd]);
435                 osd->o_incarnation++;
436         }
437         return ret;
438 }
439
440 static void __insert_osd(struct ceph_osd_client *osdc, struct ceph_osd *new)
441 {
442         struct rb_node **p = &osdc->osds.rb_node;
443         struct rb_node *parent = NULL;
444         struct ceph_osd *osd = NULL;
445
446         while (*p) {
447                 parent = *p;
448                 osd = rb_entry(parent, struct ceph_osd, o_node);
449                 if (new->o_osd < osd->o_osd)
450                         p = &(*p)->rb_left;
451                 else if (new->o_osd > osd->o_osd)
452                         p = &(*p)->rb_right;
453                 else
454                         BUG();
455         }
456
457         rb_link_node(&new->o_node, parent, p);
458         rb_insert_color(&new->o_node, &osdc->osds);
459 }
460
461 static struct ceph_osd *__lookup_osd(struct ceph_osd_client *osdc, int o)
462 {
463         struct ceph_osd *osd;
464         struct rb_node *n = osdc->osds.rb_node;
465
466         while (n) {
467                 osd = rb_entry(n, struct ceph_osd, o_node);
468                 if (o < osd->o_osd)
469                         n = n->rb_left;
470                 else if (o > osd->o_osd)
471                         n = n->rb_right;
472                 else
473                         return osd;
474         }
475         return NULL;
476 }
477
478 static void __schedule_osd_timeout(struct ceph_osd_client *osdc)
479 {
480         schedule_delayed_work(&osdc->timeout_work,
481                         osdc->client->mount_args->osd_keepalive_timeout * HZ);
482 }
483
484 static void __cancel_osd_timeout(struct ceph_osd_client *osdc)
485 {
486         cancel_delayed_work(&osdc->timeout_work);
487 }
488
489 /*
490  * Register request, assign tid.  If this is the first request, set up
491  * the timeout event.
492  */
493 static void register_request(struct ceph_osd_client *osdc,
494                              struct ceph_osd_request *req)
495 {
496         mutex_lock(&osdc->request_mutex);
497         req->r_tid = ++osdc->last_tid;
498         req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
499         INIT_LIST_HEAD(&req->r_req_lru_item);
500
501         dout("register_request %p tid %lld\n", req, req->r_tid);
502         __insert_request(osdc, req);
503         ceph_osdc_get_request(req);
504         osdc->num_requests++;
505
506         if (osdc->num_requests == 1) {
507                 dout(" first request, scheduling timeout\n");
508                 __schedule_osd_timeout(osdc);
509         }
510         mutex_unlock(&osdc->request_mutex);
511 }
512
513 /*
514  * called under osdc->request_mutex
515  */
516 static void __unregister_request(struct ceph_osd_client *osdc,
517                                  struct ceph_osd_request *req)
518 {
519         dout("__unregister_request %p tid %lld\n", req, req->r_tid);
520         rb_erase(&req->r_node, &osdc->requests);
521         osdc->num_requests--;
522
523         if (req->r_osd) {
524                 /* make sure the original request isn't in flight. */
525                 ceph_con_revoke(&req->r_osd->o_con, req->r_request);
526
527                 list_del_init(&req->r_osd_item);
528                 if (list_empty(&req->r_osd->o_requests))
529                         __move_osd_to_lru(osdc, req->r_osd);
530                 req->r_osd = NULL;
531         }
532
533         ceph_osdc_put_request(req);
534
535         list_del_init(&req->r_req_lru_item);
536         if (osdc->num_requests == 0) {
537                 dout(" no requests, canceling timeout\n");
538                 __cancel_osd_timeout(osdc);
539         }
540 }
541
542 /*
543  * Cancel a previously queued request message
544  */
545 static void __cancel_request(struct ceph_osd_request *req)
546 {
547         if (req->r_sent) {
548                 ceph_con_revoke(&req->r_osd->o_con, req->r_request);
549                 req->r_sent = 0;
550         }
551         list_del_init(&req->r_req_lru_item);
552 }
553
554 /*
555  * Pick an osd (the first 'up' osd in the pg), allocate the osd struct
556  * (as needed), and set the request r_osd appropriately.  If there is
557  * no up osd, set r_osd to NULL.
558  *
559  * Return 0 if unchanged, 1 if changed, or negative on error.
560  *
561  * Caller should hold map_sem for read and request_mutex.
562  */
563 static int __map_osds(struct ceph_osd_client *osdc,
564                       struct ceph_osd_request *req)
565 {
566         struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
567         struct ceph_pg pgid;
568         int acting[CEPH_PG_MAX_SIZE];
569         int o = -1, num = 0;
570         int err;
571
572         dout("map_osds %p tid %lld\n", req, req->r_tid);
573         err = ceph_calc_object_layout(&reqhead->layout, req->r_oid,
574                                       &req->r_file_layout, osdc->osdmap);
575         if (err)
576                 return err;
577         pgid = reqhead->layout.ol_pgid;
578         req->r_pgid = pgid;
579
580         err = ceph_calc_pg_acting(osdc->osdmap, pgid, acting);
581         if (err > 0) {
582                 o = acting[0];
583                 num = err;
584         }
585
586         if ((req->r_osd && req->r_osd->o_osd == o &&
587              req->r_sent >= req->r_osd->o_incarnation &&
588              req->r_num_pg_osds == num &&
589              memcmp(req->r_pg_osds, acting, sizeof(acting[0])*num) == 0) ||
590             (req->r_osd == NULL && o == -1))
591                 return 0;  /* no change */
592
593         dout("map_osds tid %llu pgid %d.%x osd%d (was osd%d)\n",
594              req->r_tid, le32_to_cpu(pgid.pool), le16_to_cpu(pgid.ps), o,
595              req->r_osd ? req->r_osd->o_osd : -1);
596
597         /* record full pg acting set */
598         memcpy(req->r_pg_osds, acting, sizeof(acting[0]) * num);
599         req->r_num_pg_osds = num;
600
601         if (req->r_osd) {
602                 __cancel_request(req);
603                 list_del_init(&req->r_osd_item);
604                 req->r_osd = NULL;
605         }
606
607         req->r_osd = __lookup_osd(osdc, o);
608         if (!req->r_osd && o >= 0) {
609                 err = -ENOMEM;
610                 req->r_osd = create_osd(osdc);
611                 if (!req->r_osd)
612                         goto out;
613
614                 dout("map_osds osd %p is osd%d\n", req->r_osd, o);
615                 req->r_osd->o_osd = o;
616                 req->r_osd->o_con.peer_name.num = cpu_to_le64(o);
617                 __insert_osd(osdc, req->r_osd);
618
619                 ceph_con_open(&req->r_osd->o_con, &osdc->osdmap->osd_addr[o]);
620         }
621
622         if (req->r_osd) {
623                 __remove_osd_from_lru(req->r_osd);
624                 list_add(&req->r_osd_item, &req->r_osd->o_requests);
625         }
626         err = 1;   /* osd or pg changed */
627
628 out:
629         return err;
630 }
631
632 /*
633  * caller should hold map_sem (for read) and request_mutex
634  */
635 static int __send_request(struct ceph_osd_client *osdc,
636                           struct ceph_osd_request *req)
637 {
638         struct ceph_osd_request_head *reqhead;
639         int err;
640
641         err = __map_osds(osdc, req);
642         if (err < 0)
643                 return err;
644         if (req->r_osd == NULL) {
645                 dout("send_request %p no up osds in pg\n", req);
646                 ceph_monc_request_next_osdmap(&osdc->client->monc);
647                 return 0;
648         }
649
650         dout("send_request %p tid %llu to osd%d flags %d\n",
651              req, req->r_tid, req->r_osd->o_osd, req->r_flags);
652
653         reqhead = req->r_request->front.iov_base;
654         reqhead->osdmap_epoch = cpu_to_le32(osdc->osdmap->epoch);
655         reqhead->flags |= cpu_to_le32(req->r_flags);  /* e.g., RETRY */
656         reqhead->reassert_version = req->r_reassert_version;
657
658         req->r_stamp = jiffies;
659         list_move_tail(&osdc->req_lru, &req->r_req_lru_item);
660
661         ceph_msg_get(req->r_request); /* send consumes a ref */
662         ceph_con_send(&req->r_osd->o_con, req->r_request);
663         req->r_sent = req->r_osd->o_incarnation;
664         return 0;
665 }
666
667 /*
668  * Timeout callback, called every N seconds when 1 or more osd
669  * requests has been active for more than N seconds.  When this
670  * happens, we ping all OSDs with requests who have timed out to
671  * ensure any communications channel reset is detected.  Reset the
672  * request timeouts another N seconds in the future as we go.
673  * Reschedule the timeout event another N seconds in future (unless
674  * there are no open requests).
675  */
676 static void handle_timeout(struct work_struct *work)
677 {
678         struct ceph_osd_client *osdc =
679                 container_of(work, struct ceph_osd_client, timeout_work.work);
680         struct ceph_osd_request *req, *last_req = NULL;
681         struct ceph_osd *osd;
682         unsigned long timeout = osdc->client->mount_args->osd_timeout * HZ;
683         unsigned long keepalive =
684                 osdc->client->mount_args->osd_keepalive_timeout * HZ;
685         unsigned long last_stamp = 0;
686         struct rb_node *p;
687         struct list_head slow_osds;
688
689         dout("timeout\n");
690         down_read(&osdc->map_sem);
691
692         ceph_monc_request_next_osdmap(&osdc->client->monc);
693
694         mutex_lock(&osdc->request_mutex);
695         for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
696                 req = rb_entry(p, struct ceph_osd_request, r_node);
697
698                 if (req->r_resend) {
699                         int err;
700
701                         dout("osdc resending prev failed %lld\n", req->r_tid);
702                         err = __send_request(osdc, req);
703                         if (err)
704                                 dout("osdc failed again on %lld\n", req->r_tid);
705                         else
706                                 req->r_resend = false;
707                         continue;
708                 }
709         }
710
711         /*
712          * reset osds that appear to be _really_ unresponsive.  this
713          * is a failsafe measure.. we really shouldn't be getting to
714          * this point if the system is working properly.  the monitors
715          * should mark the osd as failed and we should find out about
716          * it from an updated osd map.
717          */
718         while (!list_empty(&osdc->req_lru)) {
719                 req = list_entry(osdc->req_lru.next, struct ceph_osd_request,
720                                  r_req_lru_item);
721
722                 if (time_before(jiffies, req->r_stamp + timeout))
723                         break;
724
725                 BUG_ON(req == last_req && req->r_stamp == last_stamp);
726                 last_req = req;
727                 last_stamp = req->r_stamp;
728
729                 osd = req->r_osd;
730                 BUG_ON(!osd);
731                 pr_warning(" tid %llu timed out on osd%d, will reset osd\n",
732                            req->r_tid, osd->o_osd);
733                 __kick_requests(osdc, osd);
734         }
735
736         /*
737          * ping osds that are a bit slow.  this ensures that if there
738          * is a break in the TCP connection we will notice, and reopen
739          * a connection with that osd (from the fault callback).
740          */
741         INIT_LIST_HEAD(&slow_osds);
742         list_for_each_entry(req, &osdc->req_lru, r_req_lru_item) {
743                 if (time_before(jiffies, req->r_stamp + keepalive))
744                         break;
745
746                 osd = req->r_osd;
747                 BUG_ON(!osd);
748                 dout(" tid %llu is slow, will send keepalive on osd%d\n",
749                      req->r_tid, osd->o_osd);
750                 list_move_tail(&osd->o_keepalive_item, &slow_osds);
751         }
752         while (!list_empty(&slow_osds)) {
753                 osd = list_entry(slow_osds.next, struct ceph_osd,
754                                  o_keepalive_item);
755                 list_del_init(&osd->o_keepalive_item);
756                 ceph_con_keepalive(&osd->o_con);
757         }
758
759         __schedule_osd_timeout(osdc);
760         mutex_unlock(&osdc->request_mutex);
761
762         up_read(&osdc->map_sem);
763 }
764
765 static void handle_osds_timeout(struct work_struct *work)
766 {
767         struct ceph_osd_client *osdc =
768                 container_of(work, struct ceph_osd_client,
769                              osds_timeout_work.work);
770         unsigned long delay =
771                 osdc->client->mount_args->osd_idle_ttl * HZ >> 2;
772
773         dout("osds timeout\n");
774         down_read(&osdc->map_sem);
775         remove_old_osds(osdc, 0);
776         up_read(&osdc->map_sem);
777
778         schedule_delayed_work(&osdc->osds_timeout_work,
779                               round_jiffies_relative(delay));
780 }
781
782 /*
783  * handle osd op reply.  either call the callback if it is specified,
784  * or do the completion to wake up the waiting thread.
785  */
786 static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg,
787                          struct ceph_connection *con)
788 {
789         struct ceph_osd_reply_head *rhead = msg->front.iov_base;
790         struct ceph_osd_request *req;
791         u64 tid;
792         int numops, object_len, flags;
793         s32 result;
794
795         tid = le64_to_cpu(msg->hdr.tid);
796         if (msg->front.iov_len < sizeof(*rhead))
797                 goto bad;
798         numops = le32_to_cpu(rhead->num_ops);
799         object_len = le32_to_cpu(rhead->object_len);
800         result = le32_to_cpu(rhead->result);
801         if (msg->front.iov_len != sizeof(*rhead) + object_len +
802             numops * sizeof(struct ceph_osd_op))
803                 goto bad;
804         dout("handle_reply %p tid %llu result %d\n", msg, tid, (int)result);
805
806         /* lookup */
807         mutex_lock(&osdc->request_mutex);
808         req = __lookup_request(osdc, tid);
809         if (req == NULL) {
810                 dout("handle_reply tid %llu dne\n", tid);
811                 mutex_unlock(&osdc->request_mutex);
812                 return;
813         }
814         ceph_osdc_get_request(req);
815         flags = le32_to_cpu(rhead->flags);
816
817         /*
818          * if this connection filled our message, drop our reference now, to
819          * avoid a (safe but slower) revoke later.
820          */
821         if (req->r_con_filling_msg == con && req->r_reply == msg) {
822                 dout(" dropping con_filling_msg ref %p\n", con);
823                 req->r_con_filling_msg = NULL;
824                 ceph_con_put(con);
825         }
826
827         if (!req->r_got_reply) {
828                 unsigned bytes;
829
830                 req->r_result = le32_to_cpu(rhead->result);
831                 bytes = le32_to_cpu(msg->hdr.data_len);
832                 dout("handle_reply result %d bytes %d\n", req->r_result,
833                      bytes);
834                 if (req->r_result == 0)
835                         req->r_result = bytes;
836
837                 /* in case this is a write and we need to replay, */
838                 req->r_reassert_version = rhead->reassert_version;
839
840                 req->r_got_reply = 1;
841         } else if ((flags & CEPH_OSD_FLAG_ONDISK) == 0) {
842                 dout("handle_reply tid %llu dup ack\n", tid);
843                 mutex_unlock(&osdc->request_mutex);
844                 goto done;
845         }
846
847         dout("handle_reply tid %llu flags %d\n", tid, flags);
848
849         /* either this is a read, or we got the safe response */
850         if (result < 0 ||
851             (flags & CEPH_OSD_FLAG_ONDISK) ||
852             ((flags & CEPH_OSD_FLAG_WRITE) == 0))
853                 __unregister_request(osdc, req);
854
855         mutex_unlock(&osdc->request_mutex);
856
857         if (req->r_callback)
858                 req->r_callback(req, msg);
859         else
860                 complete(&req->r_completion);
861
862         if (flags & CEPH_OSD_FLAG_ONDISK) {
863                 if (req->r_safe_callback)
864                         req->r_safe_callback(req, msg);
865                 complete(&req->r_safe_completion);  /* fsync waiter */
866         }
867
868 done:
869         ceph_osdc_put_request(req);
870         return;
871
872 bad:
873         pr_err("corrupt osd_op_reply got %d %d expected %d\n",
874                (int)msg->front.iov_len, le32_to_cpu(msg->hdr.front_len),
875                (int)sizeof(*rhead));
876         ceph_msg_dump(msg);
877 }
878
879
880 static int __kick_requests(struct ceph_osd_client *osdc,
881                           struct ceph_osd *kickosd)
882 {
883         struct ceph_osd_request *req;
884         struct rb_node *p, *n;
885         int needmap = 0;
886         int err;
887
888         dout("kick_requests osd%d\n", kickosd ? kickosd->o_osd : -1);
889         if (kickosd) {
890                 err = __reset_osd(osdc, kickosd);
891                 if (err == -EAGAIN)
892                         return 1;
893         } else {
894                 for (p = rb_first(&osdc->osds); p; p = n) {
895                         struct ceph_osd *osd =
896                                 rb_entry(p, struct ceph_osd, o_node);
897
898                         n = rb_next(p);
899                         if (!ceph_osd_is_up(osdc->osdmap, osd->o_osd) ||
900                             memcmp(&osd->o_con.peer_addr,
901                                    ceph_osd_addr(osdc->osdmap,
902                                                  osd->o_osd),
903                                    sizeof(struct ceph_entity_addr)) != 0)
904                                 __reset_osd(osdc, osd);
905                 }
906         }
907
908         for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
909                 req = rb_entry(p, struct ceph_osd_request, r_node);
910
911                 if (req->r_resend) {
912                         dout(" r_resend set on tid %llu\n", req->r_tid);
913                         __cancel_request(req);
914                         goto kick;
915                 }
916                 if (req->r_osd && kickosd == req->r_osd) {
917                         __cancel_request(req);
918                         goto kick;
919                 }
920
921                 err = __map_osds(osdc, req);
922                 if (err == 0)
923                         continue;  /* no change */
924                 if (err < 0) {
925                         /*
926                          * FIXME: really, we should set the request
927                          * error and fail if this isn't a 'nofail'
928                          * request, but that's a fair bit more
929                          * complicated to do.  So retry!
930                          */
931                         dout(" setting r_resend on %llu\n", req->r_tid);
932                         req->r_resend = true;
933                         continue;
934                 }
935                 if (req->r_osd == NULL) {
936                         dout("tid %llu maps to no valid osd\n", req->r_tid);
937                         needmap++;  /* request a newer map */
938                         continue;
939                 }
940
941 kick:
942                 dout("kicking %p tid %llu osd%d\n", req, req->r_tid,
943                      req->r_osd ? req->r_osd->o_osd : -1);
944                 req->r_flags |= CEPH_OSD_FLAG_RETRY;
945                 err = __send_request(osdc, req);
946                 if (err) {
947                         dout(" setting r_resend on %llu\n", req->r_tid);
948                         req->r_resend = true;
949                 }
950         }
951
952         return needmap;
953 }
954
955 /*
956  * Resubmit osd requests whose osd or osd address has changed.  Request
957  * a new osd map if osds are down, or we are otherwise unable to determine
958  * how to direct a request.
959  *
960  * Close connections to down osds.
961  *
962  * If @who is specified, resubmit requests for that specific osd.
963  *
964  * Caller should hold map_sem for read and request_mutex.
965  */
966 static void kick_requests(struct ceph_osd_client *osdc,
967                           struct ceph_osd *kickosd)
968 {
969         int needmap;
970
971         mutex_lock(&osdc->request_mutex);
972         needmap = __kick_requests(osdc, kickosd);
973         mutex_unlock(&osdc->request_mutex);
974
975         if (needmap) {
976                 dout("%d requests for down osds, need new map\n", needmap);
977                 ceph_monc_request_next_osdmap(&osdc->client->monc);
978         }
979
980 }
981 /*
982  * Process updated osd map.
983  *
984  * The message contains any number of incremental and full maps, normally
985  * indicating some sort of topology change in the cluster.  Kick requests
986  * off to different OSDs as needed.
987  */
988 void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
989 {
990         void *p, *end, *next;
991         u32 nr_maps, maplen;
992         u32 epoch;
993         struct ceph_osdmap *newmap = NULL, *oldmap;
994         int err;
995         struct ceph_fsid fsid;
996
997         dout("handle_map have %u\n", osdc->osdmap ? osdc->osdmap->epoch : 0);
998         p = msg->front.iov_base;
999         end = p + msg->front.iov_len;
1000
1001         /* verify fsid */
1002         ceph_decode_need(&p, end, sizeof(fsid), bad);
1003         ceph_decode_copy(&p, &fsid, sizeof(fsid));
1004         if (ceph_check_fsid(osdc->client, &fsid) < 0)
1005                 return;
1006
1007         down_write(&osdc->map_sem);
1008
1009         /* incremental maps */
1010         ceph_decode_32_safe(&p, end, nr_maps, bad);
1011         dout(" %d inc maps\n", nr_maps);
1012         while (nr_maps > 0) {
1013                 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
1014                 epoch = ceph_decode_32(&p);
1015                 maplen = ceph_decode_32(&p);
1016                 ceph_decode_need(&p, end, maplen, bad);
1017                 next = p + maplen;
1018                 if (osdc->osdmap && osdc->osdmap->epoch+1 == epoch) {
1019                         dout("applying incremental map %u len %d\n",
1020                              epoch, maplen);
1021                         newmap = osdmap_apply_incremental(&p, next,
1022                                                           osdc->osdmap,
1023                                                           osdc->client->msgr);
1024                         if (IS_ERR(newmap)) {
1025                                 err = PTR_ERR(newmap);
1026                                 goto bad;
1027                         }
1028                         BUG_ON(!newmap);
1029                         if (newmap != osdc->osdmap) {
1030                                 ceph_osdmap_destroy(osdc->osdmap);
1031                                 osdc->osdmap = newmap;
1032                         }
1033                 } else {
1034                         dout("ignoring incremental map %u len %d\n",
1035                              epoch, maplen);
1036                 }
1037                 p = next;
1038                 nr_maps--;
1039         }
1040         if (newmap)
1041                 goto done;
1042
1043         /* full maps */
1044         ceph_decode_32_safe(&p, end, nr_maps, bad);
1045         dout(" %d full maps\n", nr_maps);
1046         while (nr_maps) {
1047                 ceph_decode_need(&p, end, 2*sizeof(u32), bad);
1048                 epoch = ceph_decode_32(&p);
1049                 maplen = ceph_decode_32(&p);
1050                 ceph_decode_need(&p, end, maplen, bad);
1051                 if (nr_maps > 1) {
1052                         dout("skipping non-latest full map %u len %d\n",
1053                              epoch, maplen);
1054                 } else if (osdc->osdmap && osdc->osdmap->epoch >= epoch) {
1055                         dout("skipping full map %u len %d, "
1056                              "older than our %u\n", epoch, maplen,
1057                              osdc->osdmap->epoch);
1058                 } else {
1059                         dout("taking full map %u len %d\n", epoch, maplen);
1060                         newmap = osdmap_decode(&p, p+maplen);
1061                         if (IS_ERR(newmap)) {
1062                                 err = PTR_ERR(newmap);
1063                                 goto bad;
1064                         }
1065                         BUG_ON(!newmap);
1066                         oldmap = osdc->osdmap;
1067                         osdc->osdmap = newmap;
1068                         if (oldmap)
1069                                 ceph_osdmap_destroy(oldmap);
1070                 }
1071                 p += maplen;
1072                 nr_maps--;
1073         }
1074
1075 done:
1076         downgrade_write(&osdc->map_sem);
1077         ceph_monc_got_osdmap(&osdc->client->monc, osdc->osdmap->epoch);
1078         if (newmap)
1079                 kick_requests(osdc, NULL);
1080         up_read(&osdc->map_sem);
1081         return;
1082
1083 bad:
1084         pr_err("osdc handle_map corrupt msg\n");
1085         ceph_msg_dump(msg);
1086         up_write(&osdc->map_sem);
1087         return;
1088 }
1089
1090
1091 /*
1092  * A read request prepares specific pages that data is to be read into.
1093  * When a message is being read off the wire, we call prepare_pages to
1094  * find those pages.
1095  *  0 = success, -1 failure.
1096  */
1097 static int __prepare_pages(struct ceph_connection *con,
1098                          struct ceph_msg_header *hdr,
1099                          struct ceph_osd_request *req,
1100                          u64 tid,
1101                          struct ceph_msg *m)
1102 {
1103         struct ceph_osd *osd = con->private;
1104         struct ceph_osd_client *osdc;
1105         int ret = -1;
1106         int data_len = le32_to_cpu(hdr->data_len);
1107         unsigned data_off = le16_to_cpu(hdr->data_off);
1108
1109         int want = calc_pages_for(data_off & ~PAGE_MASK, data_len);
1110
1111         if (!osd)
1112                 return -1;
1113
1114         osdc = osd->o_osdc;
1115
1116         dout("__prepare_pages on msg %p tid %llu, has %d pages, want %d\n", m,
1117              tid, req->r_num_pages, want);
1118         if (unlikely(req->r_num_pages < want))
1119                 goto out;
1120         m->pages = req->r_pages;
1121         m->nr_pages = req->r_num_pages;
1122         ret = 0; /* success */
1123 out:
1124         BUG_ON(ret < 0 || m->nr_pages < want);
1125
1126         return ret;
1127 }
1128
1129 /*
1130  * Register request, send initial attempt.
1131  */
1132 int ceph_osdc_start_request(struct ceph_osd_client *osdc,
1133                             struct ceph_osd_request *req,
1134                             bool nofail)
1135 {
1136         int rc = 0;
1137
1138         req->r_request->pages = req->r_pages;
1139         req->r_request->nr_pages = req->r_num_pages;
1140
1141         register_request(osdc, req);
1142
1143         down_read(&osdc->map_sem);
1144         mutex_lock(&osdc->request_mutex);
1145         /*
1146          * a racing kick_requests() may have sent the message for us
1147          * while we dropped request_mutex above, so only send now if
1148          * the request still han't been touched yet.
1149          */
1150         if (req->r_sent == 0) {
1151                 rc = __send_request(osdc, req);
1152                 if (rc) {
1153                         if (nofail) {
1154                                 dout("osdc_start_request failed send, "
1155                                      " marking %lld\n", req->r_tid);
1156                                 req->r_resend = true;
1157                                 rc = 0;
1158                         } else {
1159                                 __unregister_request(osdc, req);
1160                         }
1161                 }
1162         }
1163         mutex_unlock(&osdc->request_mutex);
1164         up_read(&osdc->map_sem);
1165         return rc;
1166 }
1167
1168 /*
1169  * wait for a request to complete
1170  */
1171 int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
1172                            struct ceph_osd_request *req)
1173 {
1174         int rc;
1175
1176         rc = wait_for_completion_interruptible(&req->r_completion);
1177         if (rc < 0) {
1178                 mutex_lock(&osdc->request_mutex);
1179                 __cancel_request(req);
1180                 __unregister_request(osdc, req);
1181                 mutex_unlock(&osdc->request_mutex);
1182                 dout("wait_request tid %llu canceled/timed out\n", req->r_tid);
1183                 return rc;
1184         }
1185
1186         dout("wait_request tid %llu result %d\n", req->r_tid, req->r_result);
1187         return req->r_result;
1188 }
1189
1190 /*
1191  * sync - wait for all in-flight requests to flush.  avoid starvation.
1192  */
1193 void ceph_osdc_sync(struct ceph_osd_client *osdc)
1194 {
1195         struct ceph_osd_request *req;
1196         u64 last_tid, next_tid = 0;
1197
1198         mutex_lock(&osdc->request_mutex);
1199         last_tid = osdc->last_tid;
1200         while (1) {
1201                 req = __lookup_request_ge(osdc, next_tid);
1202                 if (!req)
1203                         break;
1204                 if (req->r_tid > last_tid)
1205                         break;
1206
1207                 next_tid = req->r_tid + 1;
1208                 if ((req->r_flags & CEPH_OSD_FLAG_WRITE) == 0)
1209                         continue;
1210
1211                 ceph_osdc_get_request(req);
1212                 mutex_unlock(&osdc->request_mutex);
1213                 dout("sync waiting on tid %llu (last is %llu)\n",
1214                      req->r_tid, last_tid);
1215                 wait_for_completion(&req->r_safe_completion);
1216                 mutex_lock(&osdc->request_mutex);
1217                 ceph_osdc_put_request(req);
1218         }
1219         mutex_unlock(&osdc->request_mutex);
1220         dout("sync done (thru tid %llu)\n", last_tid);
1221 }
1222
1223 /*
1224  * init, shutdown
1225  */
1226 int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
1227 {
1228         int err;
1229
1230         dout("init\n");
1231         osdc->client = client;
1232         osdc->osdmap = NULL;
1233         init_rwsem(&osdc->map_sem);
1234         init_completion(&osdc->map_waiters);
1235         osdc->last_requested_map = 0;
1236         mutex_init(&osdc->request_mutex);
1237         osdc->last_tid = 0;
1238         osdc->osds = RB_ROOT;
1239         INIT_LIST_HEAD(&osdc->osd_lru);
1240         osdc->requests = RB_ROOT;
1241         INIT_LIST_HEAD(&osdc->req_lru);
1242         osdc->num_requests = 0;
1243         INIT_DELAYED_WORK(&osdc->timeout_work, handle_timeout);
1244         INIT_DELAYED_WORK(&osdc->osds_timeout_work, handle_osds_timeout);
1245
1246         schedule_delayed_work(&osdc->osds_timeout_work,
1247            round_jiffies_relative(osdc->client->mount_args->osd_idle_ttl * HZ));
1248
1249         err = -ENOMEM;
1250         osdc->req_mempool = mempool_create_kmalloc_pool(10,
1251                                         sizeof(struct ceph_osd_request));
1252         if (!osdc->req_mempool)
1253                 goto out;
1254
1255         err = ceph_msgpool_init(&osdc->msgpool_op, OSD_OP_FRONT_LEN, 10, true);
1256         if (err < 0)
1257                 goto out_mempool;
1258         err = ceph_msgpool_init(&osdc->msgpool_op_reply,
1259                                 OSD_OPREPLY_FRONT_LEN, 10, true);
1260         if (err < 0)
1261                 goto out_msgpool;
1262         return 0;
1263
1264 out_msgpool:
1265         ceph_msgpool_destroy(&osdc->msgpool_op);
1266 out_mempool:
1267         mempool_destroy(osdc->req_mempool);
1268 out:
1269         return err;
1270 }
1271
1272 void ceph_osdc_stop(struct ceph_osd_client *osdc)
1273 {
1274         cancel_delayed_work_sync(&osdc->timeout_work);
1275         cancel_delayed_work_sync(&osdc->osds_timeout_work);
1276         if (osdc->osdmap) {
1277                 ceph_osdmap_destroy(osdc->osdmap);
1278                 osdc->osdmap = NULL;
1279         }
1280         remove_old_osds(osdc, 1);
1281         mempool_destroy(osdc->req_mempool);
1282         ceph_msgpool_destroy(&osdc->msgpool_op);
1283         ceph_msgpool_destroy(&osdc->msgpool_op_reply);
1284 }
1285
1286 /*
1287  * Read some contiguous pages.  If we cross a stripe boundary, shorten
1288  * *plen.  Return number of bytes read, or error.
1289  */
1290 int ceph_osdc_readpages(struct ceph_osd_client *osdc,
1291                         struct ceph_vino vino, struct ceph_file_layout *layout,
1292                         u64 off, u64 *plen,
1293                         u32 truncate_seq, u64 truncate_size,
1294                         struct page **pages, int num_pages)
1295 {
1296         struct ceph_osd_request *req;
1297         int rc = 0;
1298
1299         dout("readpages on ino %llx.%llx on %llu~%llu\n", vino.ino,
1300              vino.snap, off, *plen);
1301         req = ceph_osdc_new_request(osdc, layout, vino, off, plen,
1302                                     CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ,
1303                                     NULL, 0, truncate_seq, truncate_size, NULL,
1304                                     false, 1);
1305         if (IS_ERR(req))
1306                 return PTR_ERR(req);
1307
1308         /* it may be a short read due to an object boundary */
1309         req->r_pages = pages;
1310         num_pages = calc_pages_for(off, *plen);
1311         req->r_num_pages = num_pages;
1312
1313         dout("readpages  final extent is %llu~%llu (%d pages)\n",
1314              off, *plen, req->r_num_pages);
1315
1316         rc = ceph_osdc_start_request(osdc, req, false);
1317         if (!rc)
1318                 rc = ceph_osdc_wait_request(osdc, req);
1319
1320         ceph_osdc_put_request(req);
1321         dout("readpages result %d\n", rc);
1322         return rc;
1323 }
1324
1325 /*
1326  * do a synchronous write on N pages
1327  */
1328 int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
1329                          struct ceph_file_layout *layout,
1330                          struct ceph_snap_context *snapc,
1331                          u64 off, u64 len,
1332                          u32 truncate_seq, u64 truncate_size,
1333                          struct timespec *mtime,
1334                          struct page **pages, int num_pages,
1335                          int flags, int do_sync, bool nofail)
1336 {
1337         struct ceph_osd_request *req;
1338         int rc = 0;
1339
1340         BUG_ON(vino.snap != CEPH_NOSNAP);
1341         req = ceph_osdc_new_request(osdc, layout, vino, off, &len,
1342                                     CEPH_OSD_OP_WRITE,
1343                                     flags | CEPH_OSD_FLAG_ONDISK |
1344                                             CEPH_OSD_FLAG_WRITE,
1345                                     snapc, do_sync,
1346                                     truncate_seq, truncate_size, mtime,
1347                                     nofail, 1);
1348         if (IS_ERR(req))
1349                 return PTR_ERR(req);
1350
1351         /* it may be a short write due to an object boundary */
1352         req->r_pages = pages;
1353         req->r_num_pages = calc_pages_for(off, len);
1354         dout("writepages %llu~%llu (%d pages)\n", off, len,
1355              req->r_num_pages);
1356
1357         rc = ceph_osdc_start_request(osdc, req, nofail);
1358         if (!rc)
1359                 rc = ceph_osdc_wait_request(osdc, req);
1360
1361         ceph_osdc_put_request(req);
1362         if (rc == 0)
1363                 rc = len;
1364         dout("writepages result %d\n", rc);
1365         return rc;
1366 }
1367
1368 /*
1369  * handle incoming message
1370  */
1371 static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
1372 {
1373         struct ceph_osd *osd = con->private;
1374         struct ceph_osd_client *osdc;
1375         int type = le16_to_cpu(msg->hdr.type);
1376
1377         if (!osd)
1378                 return;
1379         osdc = osd->o_osdc;
1380
1381         switch (type) {
1382         case CEPH_MSG_OSD_MAP:
1383                 ceph_osdc_handle_map(osdc, msg);
1384                 break;
1385         case CEPH_MSG_OSD_OPREPLY:
1386                 handle_reply(osdc, msg, con);
1387                 break;
1388
1389         default:
1390                 pr_err("received unknown message type %d %s\n", type,
1391                        ceph_msg_type_name(type));
1392         }
1393         ceph_msg_put(msg);
1394 }
1395
1396 /*
1397  * lookup and return message for incoming reply
1398  */
1399 static struct ceph_msg *get_reply(struct ceph_connection *con,
1400                                   struct ceph_msg_header *hdr,
1401                                   int *skip)
1402 {
1403         struct ceph_osd *osd = con->private;
1404         struct ceph_osd_client *osdc = osd->o_osdc;
1405         struct ceph_msg *m;
1406         struct ceph_osd_request *req;
1407         int front = le32_to_cpu(hdr->front_len);
1408         int data_len = le32_to_cpu(hdr->data_len);
1409         u64 tid;
1410         int err;
1411
1412         tid = le64_to_cpu(hdr->tid);
1413         mutex_lock(&osdc->request_mutex);
1414         req = __lookup_request(osdc, tid);
1415         if (!req) {
1416                 *skip = 1;
1417                 m = NULL;
1418                 pr_info("get_reply unknown tid %llu from osd%d\n", tid,
1419                         osd->o_osd);
1420                 goto out;
1421         }
1422
1423         if (req->r_con_filling_msg) {
1424                 dout("get_reply revoking msg %p from old con %p\n",
1425                      req->r_reply, req->r_con_filling_msg);
1426                 ceph_con_revoke_message(req->r_con_filling_msg, req->r_reply);
1427                 ceph_con_put(req->r_con_filling_msg);
1428         }
1429
1430         if (front > req->r_reply->front.iov_len) {
1431                 pr_warning("get_reply front %d > preallocated %d\n",
1432                            front, (int)req->r_reply->front.iov_len);
1433                 m = ceph_msg_new(CEPH_MSG_OSD_OPREPLY, front, 0, 0, NULL);
1434                 if (IS_ERR(m))
1435                         goto out;
1436                 ceph_msg_put(req->r_reply);
1437                 req->r_reply = m;
1438         }
1439         m = ceph_msg_get(req->r_reply);
1440
1441         if (data_len > 0) {
1442                 err = __prepare_pages(con, hdr, req, tid, m);
1443                 if (err < 0) {
1444                         *skip = 1;
1445                         ceph_msg_put(m);
1446                         m = ERR_PTR(err);
1447                 }
1448         }
1449         *skip = 0;
1450         req->r_con_filling_msg = ceph_con_get(con);
1451         dout("get_reply tid %lld %p\n", tid, m);
1452
1453 out:
1454         mutex_unlock(&osdc->request_mutex);
1455         return m;
1456
1457 }
1458
1459 static struct ceph_msg *alloc_msg(struct ceph_connection *con,
1460                                   struct ceph_msg_header *hdr,
1461                                   int *skip)
1462 {
1463         struct ceph_osd *osd = con->private;
1464         int type = le16_to_cpu(hdr->type);
1465         int front = le32_to_cpu(hdr->front_len);
1466
1467         switch (type) {
1468         case CEPH_MSG_OSD_MAP:
1469                 return ceph_msg_new(type, front, 0, 0, NULL);
1470         case CEPH_MSG_OSD_OPREPLY:
1471                 return get_reply(con, hdr, skip);
1472         default:
1473                 pr_info("alloc_msg unexpected msg type %d from osd%d\n", type,
1474                         osd->o_osd);
1475                 *skip = 1;
1476                 return NULL;
1477         }
1478 }
1479
1480 /*
1481  * Wrappers to refcount containing ceph_osd struct
1482  */
1483 static struct ceph_connection *get_osd_con(struct ceph_connection *con)
1484 {
1485         struct ceph_osd *osd = con->private;
1486         if (get_osd(osd))
1487                 return con;
1488         return NULL;
1489 }
1490
1491 static void put_osd_con(struct ceph_connection *con)
1492 {
1493         struct ceph_osd *osd = con->private;
1494         put_osd(osd);
1495 }
1496
1497 /*
1498  * authentication
1499  */
1500 static int get_authorizer(struct ceph_connection *con,
1501                           void **buf, int *len, int *proto,
1502                           void **reply_buf, int *reply_len, int force_new)
1503 {
1504         struct ceph_osd *o = con->private;
1505         struct ceph_osd_client *osdc = o->o_osdc;
1506         struct ceph_auth_client *ac = osdc->client->monc.auth;
1507         int ret = 0;
1508
1509         if (force_new && o->o_authorizer) {
1510                 ac->ops->destroy_authorizer(ac, o->o_authorizer);
1511                 o->o_authorizer = NULL;
1512         }
1513         if (o->o_authorizer == NULL) {
1514                 ret = ac->ops->create_authorizer(
1515                         ac, CEPH_ENTITY_TYPE_OSD,
1516                         &o->o_authorizer,
1517                         &o->o_authorizer_buf,
1518                         &o->o_authorizer_buf_len,
1519                         &o->o_authorizer_reply_buf,
1520                         &o->o_authorizer_reply_buf_len);
1521                 if (ret)
1522                 return ret;
1523         }
1524
1525         *proto = ac->protocol;
1526         *buf = o->o_authorizer_buf;
1527         *len = o->o_authorizer_buf_len;
1528         *reply_buf = o->o_authorizer_reply_buf;
1529         *reply_len = o->o_authorizer_reply_buf_len;
1530         return 0;
1531 }
1532
1533
1534 static int verify_authorizer_reply(struct ceph_connection *con, int len)
1535 {
1536         struct ceph_osd *o = con->private;
1537         struct ceph_osd_client *osdc = o->o_osdc;
1538         struct ceph_auth_client *ac = osdc->client->monc.auth;
1539
1540         return ac->ops->verify_authorizer_reply(ac, o->o_authorizer, len);
1541 }
1542
1543 static int invalidate_authorizer(struct ceph_connection *con)
1544 {
1545         struct ceph_osd *o = con->private;
1546         struct ceph_osd_client *osdc = o->o_osdc;
1547         struct ceph_auth_client *ac = osdc->client->monc.auth;
1548
1549         if (ac->ops->invalidate_authorizer)
1550                 ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_OSD);
1551
1552         return ceph_monc_validate_auth(&osdc->client->monc);
1553 }
1554
1555 const static struct ceph_connection_operations osd_con_ops = {
1556         .get = get_osd_con,
1557         .put = put_osd_con,
1558         .dispatch = dispatch,
1559         .get_authorizer = get_authorizer,
1560         .verify_authorizer_reply = verify_authorizer_reply,
1561         .invalidate_authorizer = invalidate_authorizer,
1562         .alloc_msg = alloc_msg,
1563         .fault = osd_reset,
1564 };