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