fs/nfs/callback_proc.c

   1 /*
   2  * linux/fs/nfs/callback_proc.c
   3  *
   4  * Copyright (C) 2004 Trond Myklebust
   5  *
   6  * NFSv4 callback procedures
   7  */
   8 #include <linux/nfs4.h>
   9 #include <linux/nfs_fs.h>
  10 #include <linux/slab.h>
  11 #include <linux/rcupdate.h>
  12 #include "nfs4_fs.h"
  13 #include "callback.h"
  14 #include "delegation.h"
  15 #include "internal.h"
  16 #include "pnfs.h"
  17 #include "nfs4session.h"
  18 #include "nfs4trace.h"
  19
  20 #ifdef NFS_DEBUG
  21 #define NFSDBG_FACILITY NFSDBG_CALLBACK
  22 #endif
  23
  24 __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
  25                              struct cb_getattrres *res,
  26                              struct cb_process_state *cps)
  27 {
  28         struct nfs_delegation *delegation;
  29         struct nfs_inode *nfsi;
  30         struct inode *inode;
  31
  32         res->status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
  33         if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
  34                 goto out;
  35
  36         res->bitmap[0] = res->bitmap[1] = 0;
  37         res->status = htonl(NFS4ERR_BADHANDLE);
  38
  39         dprintk_rcu("NFS: GETATTR callback request from %s\n",
  40                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
  41
  42         inode = nfs_delegation_find_inode(cps->clp, &args->fh);
  43         if (inode == NULL)
  44                 goto out;
  45         nfsi = NFS_I(inode);
  46         rcu_read_lock();
  47         delegation = rcu_dereference(nfsi->delegation);
  48         if (delegation == NULL || (delegation->type & FMODE_WRITE) == 0)
  49                 goto out_iput;
  50         res->size = i_size_read(inode);
  51         res->change_attr = delegation->change_attr;
  52         if (nfsi->npages != 0)
  53                 res->change_attr++;
  54         res->ctime = inode->i_ctime;
  55         res->mtime = inode->i_mtime;
  56         res->bitmap[0] = (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE) &
  57                 args->bitmap[0];
  58         res->bitmap[1] = (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY) &
  59                 args->bitmap[1];
  60         res->status = 0;
  61 out_iput:
  62         rcu_read_unlock();
  63         iput(inode);
  64 out:
  65         dprintk("%s: exit with status = %d\n", __func__, ntohl(res->status));
  66         return res->status;
  67 }
  68
  69 __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
  70                             struct cb_process_state *cps)
  71 {
  72         struct inode *inode;
  73         __be32 res;
  74
  75         res = htonl(NFS4ERR_OP_NOT_IN_SESSION);
  76         if (!cps->clp) /* Always set for v4.0. Set in cb_sequence for v4.1 */
  77                 goto out;
  78
  79         dprintk_rcu("NFS: RECALL callback request from %s\n",
  80                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
  81
  82         res = htonl(NFS4ERR_BADHANDLE);
  83         inode = nfs_delegation_find_inode(cps->clp, &args->fh);
  84         if (inode == NULL)
  85                 goto out;
  86         /* Set up a helper thread to actually return the delegation */
  87         switch (nfs_async_inode_return_delegation(inode, &args->stateid)) {
  88         case 0:
  89                 res = 0;
  90                 break;
  91         case -ENOENT:
  92                 res = htonl(NFS4ERR_BAD_STATEID);
  93                 break;
  94         default:
  95                 res = htonl(NFS4ERR_RESOURCE);
  96         }
  97         trace_nfs4_recall_delegation(inode, -ntohl(res));
  98         iput(inode);
  99 out:
 100         dprintk("%s: exit with status = %d\n", __func__, ntohl(res));
 101         return res;
 102 }
 103
 104 #if defined(CONFIG_NFS_V4_1)
 105
 106 /*
 107  * Lookup a layout by filehandle.
 108  *
 109  * Note: gets a refcount on the layout hdr and on its respective inode.
 110  * Caller must put the layout hdr and the inode.
 111  *
 112  * TODO: keep track of all layouts (and delegations) in a hash table
 113  * hashed by filehandle.
 114  */
 115 static struct pnfs_layout_hdr * get_layout_by_fh_locked(struct nfs_client *clp, struct nfs_fh *fh)
 116 {
 117         struct nfs_server *server;
 118         struct inode *ino;
 119         struct pnfs_layout_hdr *lo;
 120
 121         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
 122                 list_for_each_entry(lo, &server->layouts, plh_layouts) {
 123                         if (nfs_compare_fh(fh, &NFS_I(lo->plh_inode)->fh))
 124                                 continue;
 125                         ino = igrab(lo->plh_inode);
 126                         if (!ino)
 127                                 continue;
 128                         spin_lock(&ino->i_lock);
 129                         /* Is this layout in the process of being freed? */
 130                         if (NFS_I(ino)->layout != lo) {
 131                                 spin_unlock(&ino->i_lock);
 132                                 iput(ino);
 133                                 continue;
 134                         }
 135                         pnfs_get_layout_hdr(lo);
 136                         spin_unlock(&ino->i_lock);
 137                         return lo;
 138                 }
 139         }
 140
 141         return NULL;
 142 }
 143
 144 static struct pnfs_layout_hdr * get_layout_by_fh(struct nfs_client *clp, struct nfs_fh *fh)
 145 {
 146         struct pnfs_layout_hdr *lo;
 147
 148         spin_lock(&clp->cl_lock);
 149         rcu_read_lock();
 150         lo = get_layout_by_fh_locked(clp, fh);
 151         rcu_read_unlock();
 152         spin_unlock(&clp->cl_lock);
 153
 154         return lo;
 155 }
 156
 157 static u32 initiate_file_draining(struct nfs_client *clp,
 158                                   struct cb_layoutrecallargs *args)
 159 {
 160         struct inode *ino;
 161         struct pnfs_layout_hdr *lo;
 162         u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
 163         LIST_HEAD(free_me_list);
 164
 165         lo = get_layout_by_fh(clp, &args->cbl_fh);
 166         if (!lo)
 167                 return NFS4ERR_NOMATCHING_LAYOUT;
 168
 169         ino = lo->plh_inode;
 170         spin_lock(&ino->i_lock);
 171         if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
 172             pnfs_mark_matching_lsegs_invalid(lo, &free_me_list,
 173                                         &args->cbl_range))
 174                 rv = NFS4ERR_DELAY;
 175         else
 176                 rv = NFS4ERR_NOMATCHING_LAYOUT;
 177         pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
 178         spin_unlock(&ino->i_lock);
 179         pnfs_free_lseg_list(&free_me_list);
 180         pnfs_put_layout_hdr(lo);
 181         iput(ino);
 182         return rv;
 183 }
 184
 185 static u32 initiate_bulk_draining(struct nfs_client *clp,
 186                                   struct cb_layoutrecallargs *args)
 187 {
 188         int stat;
 189
 190         if (args->cbl_recall_type == RETURN_FSID)
 191                 stat = pnfs_destroy_layouts_byfsid(clp, &args->cbl_fsid, true);
 192         else
 193                 stat = pnfs_destroy_layouts_byclid(clp, true);
 194         if (stat != 0)
 195                 return NFS4ERR_DELAY;
 196         return NFS4ERR_NOMATCHING_LAYOUT;
 197 }
 198
 199 static u32 do_callback_layoutrecall(struct nfs_client *clp,
 200                                     struct cb_layoutrecallargs *args)
 201 {
 202         u32 res;
 203
 204         dprintk("%s enter, type=%i\n", __func__, args->cbl_recall_type);
 205         if (args->cbl_recall_type == RETURN_FILE)
 206                 res = initiate_file_draining(clp, args);
 207         else
 208                 res = initiate_bulk_draining(clp, args);
 209         dprintk("%s returning %i\n", __func__, res);
 210         return res;
 211
 212 }
 213
 214 __be32 nfs4_callback_layoutrecall(struct cb_layoutrecallargs *args,
 215                                   void *dummy, struct cb_process_state *cps)
 216 {
 217         u32 res;
 218
 219         dprintk("%s: -->\n", __func__);
 220
 221         if (cps->clp)
 222                 res = do_callback_layoutrecall(cps->clp, args);
 223         else
 224                 res = NFS4ERR_OP_NOT_IN_SESSION;
 225
 226         dprintk("%s: exit with status = %d\n", __func__, res);
 227         return cpu_to_be32(res);
 228 }
 229
 230 static void pnfs_recall_all_layouts(struct nfs_client *clp)
 231 {
 232         struct cb_layoutrecallargs args;
 233
 234         /* Pretend we got a CB_LAYOUTRECALL(ALL) */
 235         memset(&args, 0, sizeof(args));
 236         args.cbl_recall_type = RETURN_ALL;
 237         /* FIXME we ignore errors, what should we do? */
 238         do_callback_layoutrecall(clp, &args);
 239 }
 240
 241 __be32 nfs4_callback_devicenotify(struct cb_devicenotifyargs *args,
 242                                   void *dummy, struct cb_process_state *cps)
 243 {
 244         int i;
 245         __be32 res = 0;
 246         struct nfs_client *clp = cps->clp;
 247         struct nfs_server *server = NULL;
 248
 249         dprintk("%s: -->\n", __func__);
 250
 251         if (!clp) {
 252                 res = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
 253                 goto out;
 254         }
 255
 256         for (i = 0; i < args->ndevs; i++) {
 257                 struct cb_devicenotifyitem *dev = &args->devs[i];
 258
 259                 if (!server ||
 260                     server->pnfs_curr_ld->id != dev->cbd_layout_type) {
 261                         rcu_read_lock();
 262                         list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
 263                                 if (server->pnfs_curr_ld &&
 264                                     server->pnfs_curr_ld->id == dev->cbd_layout_type) {
 265                                         rcu_read_unlock();
 266                                         goto found;
 267                                 }
 268                         rcu_read_unlock();
 269                         dprintk("%s: layout type %u not found\n",
 270                                 __func__, dev->cbd_layout_type);
 271                         continue;
 272                 }
 273
 274         found:
 275                 if (dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE)
 276                         dprintk("%s: NOTIFY_DEVICEID4_CHANGE not supported, "
 277                                 "deleting instead\n", __func__);
 278                 nfs4_delete_deviceid(server->pnfs_curr_ld, clp, &dev->cbd_dev_id);
 279         }
 280
 281 out:
 282         kfree(args->devs);
 283         dprintk("%s: exit with status = %u\n",
 284                 __func__, be32_to_cpu(res));
 285         return res;
 286 }
 287
 288 /*
 289  * Validate the sequenceID sent by the server.
 290  * Return success if the sequenceID is one more than what we last saw on
 291  * this slot, accounting for wraparound.  Increments the slot's sequence.
 292  *
 293  * We don't yet implement a duplicate request cache, instead we set the
 294  * back channel ca_maxresponsesize_cached to zero. This is OK for now
 295  * since we only currently implement idempotent callbacks anyway.
 296  *
 297  * We have a single slot backchannel at this time, so we don't bother
 298  * checking the used_slots bit array on the table.  The lower layer guarantees
 299  * a single outstanding callback request at a time.
 300  */
 301 static __be32
 302 validate_seqid(struct nfs4_slot_table *tbl, struct cb_sequenceargs * args)
 303 {
 304         struct nfs4_slot *slot;
 305
 306         dprintk("%s enter. slotid %u seqid %u\n",
 307                 __func__, args->csa_slotid, args->csa_sequenceid);
 308
 309         if (args->csa_slotid >= NFS41_BC_MAX_CALLBACKS)
 310                 return htonl(NFS4ERR_BADSLOT);
 311
 312         slot = tbl->slots + args->csa_slotid;
 313         dprintk("%s slot table seqid: %u\n", __func__, slot->seq_nr);
 314
 315         /* Normal */
 316         if (likely(args->csa_sequenceid == slot->seq_nr + 1)) {
 317                 slot->seq_nr++;
 318                 goto out_ok;
 319         }
 320
 321         /* Replay */
 322         if (args->csa_sequenceid == slot->seq_nr) {
 323                 dprintk("%s seqid %u is a replay\n",
 324                         __func__, args->csa_sequenceid);
 325                 /* Signal process_op to set this error on next op */
 326                 if (args->csa_cachethis == 0)
 327                         return htonl(NFS4ERR_RETRY_UNCACHED_REP);
 328
 329                 /* The ca_maxresponsesize_cached is 0 with no DRC */
 330                 else if (args->csa_cachethis == 1)
 331                         return htonl(NFS4ERR_REP_TOO_BIG_TO_CACHE);
 332         }
 333
 334         /* Wraparound */
 335         if (args->csa_sequenceid == 1 && (slot->seq_nr + 1) == 0) {
 336                 slot->seq_nr = 1;
 337                 goto out_ok;
 338         }
 339
 340         /* Misordered request */
 341         return htonl(NFS4ERR_SEQ_MISORDERED);
 342 out_ok:
 343         tbl->highest_used_slotid = args->csa_slotid;
 344         return htonl(NFS4_OK);
 345 }
 346
 347 /*
 348  * For each referring call triple, check the session's slot table for
 349  * a match.  If the slot is in use and the sequence numbers match, the
 350  * client is still waiting for a response to the original request.
 351  */
 352 static bool referring_call_exists(struct nfs_client *clp,
 353                                   uint32_t nrclists,
 354                                   struct referring_call_list *rclists)
 355 {
 356         bool status = 0;
 357         int i, j;
 358         struct nfs4_session *session;
 359         struct nfs4_slot_table *tbl;
 360         struct referring_call_list *rclist;
 361         struct referring_call *ref;
 362
 363         /*
 364          * XXX When client trunking is implemented, this becomes
 365          * a session lookup from within the loop
 366          */
 367         session = clp->cl_session;
 368         tbl = &session->fc_slot_table;
 369
 370         for (i = 0; i < nrclists; i++) {
 371                 rclist = &rclists[i];
 372                 if (memcmp(session->sess_id.data,
 373                            rclist->rcl_sessionid.data,
 374                            NFS4_MAX_SESSIONID_LEN) != 0)
 375                         continue;
 376
 377                 for (j = 0; j < rclist->rcl_nrefcalls; j++) {
 378                         ref = &rclist->rcl_refcalls[j];
 379
 380                         dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u "
 381                                 "slotid %u\n", __func__,
 382                                 ((u32 *)&rclist->rcl_sessionid.data)[0],
 383                                 ((u32 *)&rclist->rcl_sessionid.data)[1],
 384                                 ((u32 *)&rclist->rcl_sessionid.data)[2],
 385                                 ((u32 *)&rclist->rcl_sessionid.data)[3],
 386                                 ref->rc_sequenceid, ref->rc_slotid);
 387
 388                         spin_lock(&tbl->slot_tbl_lock);
 389                         status = (test_bit(ref->rc_slotid, tbl->used_slots) &&
 390                                   tbl->slots[ref->rc_slotid].seq_nr ==
 391                                         ref->rc_sequenceid);
 392                         spin_unlock(&tbl->slot_tbl_lock);
 393                         if (status)
 394                                 goto out;
 395                 }
 396         }
 397
 398 out:
 399         return status;
 400 }
 401
 402 __be32 nfs4_callback_sequence(struct cb_sequenceargs *args,
 403                               struct cb_sequenceres *res,
 404                               struct cb_process_state *cps)
 405 {
 406         struct nfs4_slot_table *tbl;
 407         struct nfs_client *clp;
 408         int i;
 409         __be32 status = htonl(NFS4ERR_BADSESSION);
 410
 411         clp = nfs4_find_client_sessionid(cps->net, args->csa_addr,
 412                                          &args->csa_sessionid, cps->minorversion);
 413         if (clp == NULL)
 414                 goto out;
 415
 416         tbl = &clp->cl_session->bc_slot_table;
 417
 418         spin_lock(&tbl->slot_tbl_lock);
 419         /* state manager is resetting the session */
 420         if (test_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
 421                 spin_unlock(&tbl->slot_tbl_lock);
 422                 status = htonl(NFS4ERR_DELAY);
 423                 /* Return NFS4ERR_BADSESSION if we're draining the session
 424                  * in order to reset it.
 425                  */
 426                 if (test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
 427                         status = htonl(NFS4ERR_BADSESSION);
 428                 goto out;
 429         }
 430
 431         status = validate_seqid(&clp->cl_session->bc_slot_table, args);
 432         spin_unlock(&tbl->slot_tbl_lock);
 433         if (status)
 434                 goto out;
 435
 436         cps->slotid = args->csa_slotid;
 437
 438         /*
 439          * Check for pending referring calls.  If a match is found, a
 440          * related callback was received before the response to the original
 441          * call.
 442          */
 443         if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
 444                 status = htonl(NFS4ERR_DELAY);
 445                 goto out;
 446         }
 447
 448         memcpy(&res->csr_sessionid, &args->csa_sessionid,
 449                sizeof(res->csr_sessionid));
 450         res->csr_sequenceid = args->csa_sequenceid;
 451         res->csr_slotid = args->csa_slotid;
 452         res->csr_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
 453         res->csr_target_highestslotid = NFS41_BC_MAX_CALLBACKS - 1;
 454
 455 out:
 456         cps->clp = clp; /* put in nfs4_callback_compound */
 457         for (i = 0; i < args->csa_nrclists; i++)
 458                 kfree(args->csa_rclists[i].rcl_refcalls);
 459         kfree(args->csa_rclists);
 460
 461         if (status == htonl(NFS4ERR_RETRY_UNCACHED_REP)) {
 462                 cps->drc_status = status;
 463                 status = 0;
 464         } else
 465                 res->csr_status = status;
 466
 467         trace_nfs4_cb_sequence(args, res, status);
 468         dprintk("%s: exit with status = %d res->csr_status %d\n", __func__,
 469                 ntohl(status), ntohl(res->csr_status));
 470         return status;
 471 }
 472
 473 static bool
 474 validate_bitmap_values(unsigned long mask)
 475 {
 476         return (mask & ~RCA4_TYPE_MASK_ALL) == 0;
 477 }
 478
 479 __be32 nfs4_callback_recallany(struct cb_recallanyargs *args, void *dummy,
 480                                struct cb_process_state *cps)
 481 {
 482         __be32 status;
 483         fmode_t flags = 0;
 484
 485         status = cpu_to_be32(NFS4ERR_OP_NOT_IN_SESSION);
 486         if (!cps->clp) /* set in cb_sequence */
 487                 goto out;
 488
 489         dprintk_rcu("NFS: RECALL_ANY callback request from %s\n",
 490                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 491
 492         status = cpu_to_be32(NFS4ERR_INVAL);
 493         if (!validate_bitmap_values(args->craa_type_mask))
 494                 goto out;
 495
 496         status = cpu_to_be32(NFS4_OK);
 497         if (test_bit(RCA4_TYPE_MASK_RDATA_DLG, (const unsigned long *)
 498                      &args->craa_type_mask))
 499                 flags = FMODE_READ;
 500         if (test_bit(RCA4_TYPE_MASK_WDATA_DLG, (const unsigned long *)
 501                      &args->craa_type_mask))
 502                 flags |= FMODE_WRITE;
 503         if (test_bit(RCA4_TYPE_MASK_FILE_LAYOUT, (const unsigned long *)
 504                      &args->craa_type_mask))
 505                 pnfs_recall_all_layouts(cps->clp);
 506         if (flags)
 507                 nfs_expire_unused_delegation_types(cps->clp, flags);
 508 out:
 509         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 510         return status;
 511 }
 512
 513 /* Reduce the fore channel's max_slots to the target value */
 514 __be32 nfs4_callback_recallslot(struct cb_recallslotargs *args, void *dummy,
 515                                 struct cb_process_state *cps)
 516 {
 517         struct nfs4_slot_table *fc_tbl;
 518         __be32 status;
 519
 520         status = htonl(NFS4ERR_OP_NOT_IN_SESSION);
 521         if (!cps->clp) /* set in cb_sequence */
 522                 goto out;
 523
 524         dprintk_rcu("NFS: CB_RECALL_SLOT request from %s target highest slotid %u\n",
 525                 rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR),
 526                 args->crsa_target_highest_slotid);
 527
 528         fc_tbl = &cps->clp->cl_session->fc_slot_table;
 529
 530         status = htonl(NFS4_OK);
 531
 532         nfs41_set_target_slotid(fc_tbl, args->crsa_target_highest_slotid);
 533         nfs41_server_notify_target_slotid_update(cps->clp);
 534 out:
 535         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 536         return status;
 537 }
 538 #endif /* CONFIG_NFS_V4_1 */