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