[bug report] afs: Add support for RENAME_NOREPLACE and RENAME_EXCHANGE

Dan Carpenter dan.carpenter at linaro.org
Thu Sep 18 10:51:31 PDT 2025


Hello David Howells,

Commit 09c69289a273 ("afs: Add support for RENAME_NOREPLACE and
RENAME_EXCHANGE") from Sep 3, 2025 (linux-next), leads to the
following Smatch static checker warning:

fs/afs/rotate.c:637 afs_select_fileserver() error: uninitialized symbol 'addr_index'.
fs/afs/rotate.c:637 afs_select_fileserver() error: uninitialized symbol 'alist'.

fs/afs/rotate.c
    152 bool afs_select_fileserver(struct afs_operation *op)
    153 {
    154         struct afs_addr_list *alist;
    155         struct afs_server *server;
    156         struct afs_vnode *vnode = op->file[0].vnode;
    157         unsigned long set, failed;
    158         s32 abort_code = op->call_abort_code;
    159         int best_prio = 0;
    160         int error = op->call_error, addr_index, i, j;
    161 
    162         op->nr_iterations++;
    163 
    164         _enter("OP=%x+%x,%llx,%u{%lx},%u{%lx},%d,%d",
    165                op->debug_id, op->nr_iterations, op->volume->vid,
    166                op->server_index, op->untried_servers,
    167                op->addr_index, op->addr_tried,
    168                error, abort_code);
    169 
    170         if (op->flags & AFS_OPERATION_STOP) {
    171                 trace_afs_rotate(op, afs_rotate_trace_stopped, 0);
    172                 _leave(" = f [stopped]");
    173                 return false;
    174         }
    175 
    176         if (op->nr_iterations == 0)
    177                 goto start;
    178 
    179         WRITE_ONCE(op->estate->addresses->addrs[op->addr_index].last_error, error);
    180         trace_afs_rotate(op, afs_rotate_trace_iter, op->call_error);
    181 
    182         /* Evaluate the result of the previous operation, if there was one. */
    183         switch (op->call_error) {
    184         case 0:
    185                 clear_bit(AFS_SE_VOLUME_OFFLINE,
    186                           &op->server_list->servers[op->server_index].flags);
    187                 clear_bit(AFS_SE_VOLUME_BUSY,
    188                           &op->server_list->servers[op->server_index].flags);
    189                 op->cumul_error.responded = true;
    190 
    191                 /* We succeeded, but we may need to redo the op from another
    192                  * server if we're looking at a set of RO volumes where some of
    193                  * the servers have not yet been brought up to date lest we
    194                  * regress the data.  We only switch to the new version once
    195                  * >=50% of the servers are updated.
    196                  */
    197                 error = afs_update_volume_state(op);
    198                 if (error != 0) {
    199                         if (error == 1) {
    200                                 afs_sleep_and_retry(op);
    201                                 goto restart_from_beginning;
    202                         }
    203                         afs_op_set_error(op, error);
    204                         goto failed;
    205                 }
    206                 fallthrough;
    207         default:
    208                 /* Success or local failure.  Stop. */
    209                 afs_op_set_error(op, error);
    210                 op->flags |= AFS_OPERATION_STOP;
    211                 trace_afs_rotate(op, afs_rotate_trace_stop, error);
    212                 _leave(" = f [okay/local %d]", error);
    213                 return false;
    214 
    215         case -ECONNABORTED:
    216                 /* The far side rejected the operation on some grounds.  This
    217                  * might involve the server being busy or the volume having been moved.
    218                  *
    219                  * Note that various V* errors should not be sent to a cache manager
    220                  * by a fileserver as they should be translated to more modern UAE*
    221                  * errors instead.  IBM AFS and OpenAFS fileservers, however, do leak
    222                  * these abort codes.
    223                  */
    224                 trace_afs_rotate(op, afs_rotate_trace_aborted, abort_code);
    225                 op->cumul_error.responded = true;
    226                 switch (abort_code) {
    227                 case VNOVOL:
    228                         /* This fileserver doesn't know about the volume.
    229                          * - May indicate that the VL is wrong - retry once and compare
    230                          *   the results.
    231                          * - May indicate that the fileserver couldn't attach to the vol.
    232                          * - The volume might have been temporarily removed so that it can
    233                          *   be replaced by a volume restore.  "vos" might have ended one
    234                          *   transaction and has yet to create the next.
    235                          * - The volume might not be blessed or might not be in-service
    236                          *   (administrative action).
    237                          */
    238                         if (op->flags & AFS_OPERATION_VNOVOL) {
    239                                 afs_op_accumulate_error(op, -EREMOTEIO, abort_code);
    240                                 goto next_server;
    241                         }
    242 
    243                         write_lock(&op->volume->servers_lock);
    244                         op->server_list->vnovol_mask |= 1 << op->server_index;
    245                         write_unlock(&op->volume->servers_lock);
    246 
    247                         set_bit(AFS_VOLUME_NEEDS_UPDATE, &op->volume->flags);
    248                         error = afs_check_volume_status(op->volume, op);
    249                         if (error < 0) {
    250                                 afs_op_set_error(op, error);
    251                                 goto failed;
    252                         }
    253 
    254                         if (test_bit(AFS_VOLUME_DELETED, &op->volume->flags)) {
    255                                 afs_op_set_error(op, -ENOMEDIUM);
    256                                 goto failed;
    257                         }
    258 
    259                         /* If the server list didn't change, then assume that
    260                          * it's the fileserver having trouble.
    261                          */
    262                         if (rcu_access_pointer(op->volume->servers) == op->server_list) {
    263                                 afs_op_accumulate_error(op, -EREMOTEIO, abort_code);
    264                                 goto next_server;
    265                         }
    266 
    267                         /* Try again */
    268                         op->flags |= AFS_OPERATION_VNOVOL;
    269                         _leave(" = t [vnovol]");
    270                         return true;
    271 
    272                 case VVOLEXISTS:
    273                 case VONLINE:
    274                         /* These should not be returned from the fileserver. */
    275                         pr_warn("Fileserver returned unexpected abort %d\n",
    276                                 abort_code);
    277                         afs_op_accumulate_error(op, -EREMOTEIO, abort_code);
    278                         goto next_server;
    279 
    280                 case VNOSERVICE:
    281                         /* Prior to AFS 3.2 VNOSERVICE was returned from the fileserver
    282                          * if the volume was neither in-service nor administratively
    283                          * blessed.  All usage was replaced by VNOVOL because AFS 3.1 and
    284                          * earlier cache managers did not handle VNOSERVICE and assumed
    285                          * it was the client OSes errno 105.
    286                          *
    287                          * Starting with OpenAFS 1.4.8 VNOSERVICE was repurposed as the
    288                          * fileserver idle dead time error which was sent in place of
    289                          * RX_CALL_TIMEOUT (-3).  The error was intended to be sent if the
    290                          * fileserver took too long to send a reply to the client.
    291                          * RX_CALL_TIMEOUT would have caused the cache manager to mark the
    292                          * server down whereas VNOSERVICE since AFS 3.2 would cause cache
    293                          * manager to temporarily (up to 15 minutes) mark the volume
    294                          * instance as unusable.
    295                          *
    296                          * The idle dead logic resulted in cache inconsistency since a
    297                          * state changing call that the cache manager assumed was dead
    298                          * could still be processed to completion by the fileserver.  This
    299                          * logic was removed in OpenAFS 1.8.0 and VNOSERVICE is no longer
    300                          * returned.  However, many 1.4.8 through 1.6.24 fileservers are
    301                          * still in existence.
    302                          *
    303                          * AuriStorFS fileservers have never returned VNOSERVICE.
    304                          *
    305                          * VNOSERVICE should be treated as an alias for RX_CALL_TIMEOUT.
    306                          */
    307                 case RX_CALL_TIMEOUT:
    308                         afs_op_accumulate_error(op, -ETIMEDOUT, abort_code);
    309                         goto next_server;
    310 
    311                 case VSALVAGING: /* This error should not be leaked to cache managers
    312                                   * but is from OpenAFS demand attach fileservers.
    313                                   * It should be treated as an alias for VOFFLINE.
    314                                   */
    315                 case VSALVAGE: /* VSALVAGE should be treated as a synonym of VOFFLINE */
    316                 case VOFFLINE:
    317                         /* The volume is in use by the volserver or another volume utility
    318                          * for an operation that might alter the contents.  The volume is
    319                          * expected to come back but it might take a long time (could be
    320                          * days).
    321                          */
    322                         if (!test_and_set_bit(AFS_SE_VOLUME_OFFLINE,
    323                                               &op->server_list->servers[op->server_index].flags)) {
    324                                 afs_busy(op, abort_code);
    325                                 clear_bit(AFS_SE_VOLUME_BUSY,
    326                                           &op->server_list->servers[op->server_index].flags);
    327                         }
    328                         if (op->flags & AFS_OPERATION_NO_VSLEEP) {
    329                                 afs_op_set_error(op, -EADV);
    330                                 goto failed;
    331                         }
    332                         goto busy;
    333 
    334                 case VRESTARTING: /* The fileserver is either shutting down or starting up. */
    335                 case VBUSY:
    336                         /* The volume is in use by the volserver or another volume
    337                          * utility for an operation that is not expected to alter the
    338                          * contents of the volume.  VBUSY does not need to be returned
    339                          * for a ROVOL or BACKVOL bound to an ITBusy volserver
    340                          * transaction.  The fileserver is permitted to continue serving
    341                          * content from ROVOLs and BACKVOLs during an ITBusy transaction
    342                          * because the content will not change.  However, many fileserver
    343                          * releases do return VBUSY for ROVOL and BACKVOL instances under
    344                          * many circumstances.
    345                          *
    346                          * Retry after going round all the servers unless we have a file
    347                          * lock we need to maintain.
    348                          */
    349                         if (op->flags & AFS_OPERATION_NO_VSLEEP) {
    350                                 afs_op_set_error(op, -EBUSY);
    351                                 goto failed;
    352                         }
    353                         if (!test_and_set_bit(AFS_SE_VOLUME_BUSY,
    354                                               &op->server_list->servers[op->server_index].flags)) {
    355                                 afs_busy(op, abort_code);
    356                                 clear_bit(AFS_SE_VOLUME_OFFLINE,
    357                                           &op->server_list->servers[op->server_index].flags);
    358                         }
    359                 busy:
    360                         if (op->flags & AFS_OPERATION_CUR_ONLY) {
    361                                 if (!afs_sleep_and_retry(op))
    362                                         goto failed;
    363 
    364                                 /* Retry with same server & address */
    365                                 _leave(" = t [vbusy]");
    366                                 return true;
    367                         }
    368 
    369                         op->flags |= AFS_OPERATION_VBUSY;
    370                         goto next_server;
    371 
    372                 case VMOVED:
    373                         /* The volume migrated to another server.  We consider
    374                          * consider all locks and callbacks broken and request
    375                          * an update from the VLDB.
    376                          *
    377                          * We also limit the number of VMOVED hops we will
    378                          * honour, just in case someone sets up a loop.
    379                          */
    380                         if (op->flags & AFS_OPERATION_VMOVED) {
    381                                 afs_op_set_error(op, -EREMOTEIO);
    382                                 goto failed;
    383                         }
    384                         op->flags |= AFS_OPERATION_VMOVED;
    385 
    386                         set_bit(AFS_VOLUME_WAIT, &op->volume->flags);
    387                         set_bit(AFS_VOLUME_NEEDS_UPDATE, &op->volume->flags);
    388                         error = afs_check_volume_status(op->volume, op);
    389                         if (error < 0) {
    390                                 afs_op_set_error(op, error);
    391                                 goto failed;
    392                         }
    393 
    394                         /* If the server list didn't change, then the VLDB is
    395                          * out of sync with the fileservers.  This is hopefully
    396                          * a temporary condition, however, so we don't want to
    397                          * permanently block access to the file.
    398                          *
    399                          * TODO: Try other fileservers if we can.
    400                          *
    401                          * TODO: Retry a few times with sleeps.
    402                          */
    403                         if (rcu_access_pointer(op->volume->servers) == op->server_list) {
    404                                 afs_op_accumulate_error(op, -ENOMEDIUM, abort_code);
    405                                 goto failed;
    406                         }
    407 
    408                         goto restart_from_beginning;
    409 
    410                 case UAEIO:
    411                 case VIO:
    412                         afs_op_accumulate_error(op, -EREMOTEIO, abort_code);
    413                         if (op->volume->type != AFSVL_RWVOL)
    414                                 goto next_server;
    415                         goto failed;
    416 
    417                 case VDISKFULL:
    418                 case UAENOSPC:
    419                         /* The partition is full.  Only applies to RWVOLs.
    420                          * Translate locally and return ENOSPC.
    421                          * No replicas to failover to.
    422                          */
    423                         afs_op_set_error(op, -ENOSPC);
    424                         goto failed_but_online;
    425 
    426                 case VOVERQUOTA:
    427                 case UAEDQUOT:
    428                         /* Volume is full.  Only applies to RWVOLs.
    429                          * Translate locally and return EDQUOT.
    430                          * No replicas to failover to.
    431                          */
    432                         afs_op_set_error(op, -EDQUOT);
    433                         goto failed_but_online;
    434 
    435                 case RX_INVALID_OPERATION:
    436                 case RXGEN_OPCODE:
    437                         /* Handle downgrading to an older operation. */
    438                         afs_op_set_error(op, -ENOTSUPP);
    439                         if (op->flags & AFS_OPERATION_DOWNGRADE) {
    440                                 op->flags &= ~AFS_OPERATION_DOWNGRADE;
    441                                 goto go_again;

addr_index is not set on this path.

    442                         }
    443                         goto failed_but_online;
    444 
    445                 default:
    446                         afs_op_accumulate_error(op, error, abort_code);
    447                 failed_but_online:
    448                         clear_bit(AFS_SE_VOLUME_OFFLINE,
    449                                   &op->server_list->servers[op->server_index].flags);
    450                         clear_bit(AFS_SE_VOLUME_BUSY,
    451                                   &op->server_list->servers[op->server_index].flags);
    452                         goto failed;
    453                 }
    454 
    455         case -ETIMEDOUT:
    456         case -ETIME:
    457                 if (afs_op_error(op) != -EDESTADDRREQ)
    458                         goto iterate_address;
    459                 fallthrough;
    460         case -ERFKILL:
    461         case -EADDRNOTAVAIL:
    462         case -ENETUNREACH:
    463         case -EHOSTUNREACH:
    464         case -EHOSTDOWN:
    465         case -ECONNREFUSED:
    466                 _debug("no conn");
    467                 afs_op_accumulate_error(op, error, 0);
    468                 goto iterate_address;
    469 
    470         case -ENETRESET:
    471                 pr_warn("kAFS: Peer reset %s (op=%x)\n",
    472                         op->type ? op->type->name : "???", op->debug_id);
    473                 fallthrough;
    474         case -ECONNRESET:
    475                 _debug("call reset");
    476                 afs_op_set_error(op, error);
    477                 goto failed;
    478         }
    479 
    480 restart_from_beginning:
    481         trace_afs_rotate(op, afs_rotate_trace_restart, 0);
    482         _debug("restart");
    483         op->estate = NULL;
    484         op->server = NULL;
    485         afs_clear_server_states(op);
    486         op->server_states = NULL;
    487         afs_put_serverlist(op->net, op->server_list);
    488         op->server_list = NULL;
    489 start:
    490         _debug("start");
    491         ASSERTCMP(op->estate, ==, NULL);
    492         /* See if we need to do an update of the volume record.  Note that the
    493          * volume may have moved or even have been deleted.
    494          */
    495         error = afs_check_volume_status(op->volume, op);
    496         trace_afs_rotate(op, afs_rotate_trace_check_vol_status, error);
    497         if (error < 0) {
    498                 afs_op_set_error(op, error);
    499                 goto failed;
    500         }
    501 
    502         if (!afs_start_fs_iteration(op, vnode))
    503                 goto failed;
    504 
    505         _debug("__ VOL %llx __", op->volume->vid);
    506 
    507 pick_server:
    508         _debug("pick [%lx]", op->untried_servers);
    509         ASSERTCMP(op->estate, ==, NULL);
    510 
    511         error = afs_wait_for_fs_probes(op, op->server_states,
    512                                        !(op->flags & AFS_OPERATION_UNINTR));
    513         switch (error) {
    514         case 0: /* No untried responsive servers and no outstanding probes */
    515                 trace_afs_rotate(op, afs_rotate_trace_probe_none, 0);
    516                 goto no_more_servers;
    517         case 1: /* Got a response */
    518                 trace_afs_rotate(op, afs_rotate_trace_probe_response, 0);
    519                 break;
    520         case 2: /* Probe data superseded */
    521                 trace_afs_rotate(op, afs_rotate_trace_probe_superseded, 0);
    522                 goto restart_from_beginning;
    523         default:
    524                 trace_afs_rotate(op, afs_rotate_trace_probe_error, error);
    525                 afs_op_set_error(op, error);
    526                 goto failed;
    527         }
    528 
    529         /* Pick the untried server with the highest priority untried endpoint.
    530          * If we have outstanding callbacks, we stick with the server we're
    531          * already using if we can.
    532          */
    533         if (op->server) {
    534                 _debug("server %u", op->server_index);
    535                 if (test_bit(op->server_index, &op->untried_servers))
    536                         goto selected_server;
    537                 op->server = NULL;
    538                 _debug("no server");
    539         }
    540 
    541         rcu_read_lock();
    542         op->server_index = -1;
    543         best_prio = -1;
    544         for (i = 0; i < op->server_list->nr_servers; i++) {
    545                 struct afs_endpoint_state *es;
    546                 struct afs_server_entry *se = &op->server_list->servers[i];
    547                 struct afs_addr_list *sal;
    548                 struct afs_server *s = se->server;
    549 
    550                 if (!test_bit(i, &op->untried_servers) ||
    551                     test_bit(AFS_SE_EXCLUDED, &se->flags) ||
    552                     !test_bit(AFS_SERVER_FL_RESPONDING, &s->flags))
    553                         continue;
    554                 es = op->server_states[i].endpoint_state;
    555                 sal = es->addresses;
    556 
    557                 afs_get_address_preferences_rcu(op->net, sal);
    558                 for (j = 0; j < sal->nr_addrs; j++) {
    559                         if (es->failed_set & (1 << j))
    560                                 continue;
    561                         if (!sal->addrs[j].peer)
    562                                 continue;
    563                         if (sal->addrs[j].prio > best_prio) {
    564                                 op->server_index = i;
    565                                 best_prio = sal->addrs[j].prio;
    566                         }
    567                 }
    568         }
    569         rcu_read_unlock();
    570 
    571         if (op->server_index == -1)
    572                 goto no_more_servers;
    573 
    574 selected_server:
    575         trace_afs_rotate(op, afs_rotate_trace_selected_server, best_prio);
    576         _debug("use %d prio %u", op->server_index, best_prio);
    577         __clear_bit(op->server_index, &op->untried_servers);
    578 
    579         /* We're starting on a different fileserver from the list.  We need to
    580          * check it, create a callback intercept, find its address list and
    581          * probe its capabilities before we use it.
    582          */
    583         ASSERTCMP(op->estate, ==, NULL);
    584         server = op->server_list->servers[op->server_index].server;
    585 
    586         if (!afs_check_server_record(op, server, op->key))
    587                 goto failed;
    588 
    589         _debug("USING SERVER: %pU", &server->uuid);
    590 
    591         op->flags |= AFS_OPERATION_RETRY_SERVER;
    592         op->server = server;
    593         if (vnode->cb_server != server) {
    594                 vnode->cb_server = server;
    595                 vnode->cb_v_check = atomic_read(&vnode->volume->cb_v_break);
    596                 afs_clear_cb_promise(vnode, afs_cb_promise_clear_server_change);
    597         }
    598 
    599 retry_server:
    600         op->addr_tried = 0;
    601         op->addr_index = -1;
    602 
    603 iterate_address:
    604         /* Iterate over the current server's address list to try and find an
    605          * address on which it will respond to us.
    606          */
    607         op->estate = op->server_states[op->server_index].endpoint_state;
    608         set = READ_ONCE(op->estate->responsive_set);
    609         failed = READ_ONCE(op->estate->failed_set);
    610         _debug("iterate ES=%x rs=%lx fs=%lx", op->estate->probe_seq, set, failed);
    611         set &= ~(failed | op->addr_tried);
    612         trace_afs_rotate(op, afs_rotate_trace_iterate_addr, set);
    613         if (!set)
    614                 goto wait_for_more_probe_results;
    615 
    616         alist = op->estate->addresses;
    617         best_prio = -1;
    618         addr_index = 0;
    619         for (i = 0; i < alist->nr_addrs; i++) {
    620                 if (!(set & (1 << i)))
    621                         continue;
    622                 if (alist->addrs[i].prio > best_prio) {
    623                         addr_index = i;
    624                         best_prio = alist->addrs[i].prio;
    625                 }
    626         }
    627 
    628         alist->preferred = addr_index;
    629 
    630         op->addr_index = addr_index;
    631         set_bit(addr_index, &op->addr_tried);
    632 
    633 go_again:
    634         op->volsync.creation = TIME64_MIN;
    635         op->volsync.update = TIME64_MIN;
    636         op->call_responded = false;
--> 637         _debug("address [%u] %u/%u %pISp",
    638                op->server_index, addr_index, alist->nr_addrs,
                                         ^^^^^^^^^^

    639                rxrpc_kernel_remote_addr(alist->addrs[op->addr_index].peer));
    640         _leave(" = t");
    641         return true;
    642 
    643 wait_for_more_probe_results:
    644         error = afs_wait_for_one_fs_probe(op->server, op->estate, op->addr_tried,
    645                                           !(op->flags & AFS_OPERATION_UNINTR));
    646         if (error == 1)
    647                 goto iterate_address;
    648         if (!error)
    649                 goto restart_from_beginning;
    650 
    651         /* We've now had a failure to respond on all of a server's addresses -
    652          * immediately probe them again and consider retrying the server.
    653          */
    654         trace_afs_rotate(op, afs_rotate_trace_probe_fileserver, 0);
    655         afs_probe_fileserver(op->net, op->server);
    656         if (op->flags & AFS_OPERATION_RETRY_SERVER) {
    657                 error = afs_wait_for_one_fs_probe(op->server, op->estate, op->addr_tried,
    658                                                   !(op->flags & AFS_OPERATION_UNINTR));
    659                 switch (error) {
    660                 case 1:
    661                         op->flags &= ~AFS_OPERATION_RETRY_SERVER;
    662                         trace_afs_rotate(op, afs_rotate_trace_retry_server, 1);
    663                         goto retry_server;
    664                 case 0:
    665                         trace_afs_rotate(op, afs_rotate_trace_retry_server, 0);
    666                         goto restart_from_beginning;
    667                 case -ERESTARTSYS:
    668                         afs_op_set_error(op, error);
    669                         goto failed;
    670                 case -ETIME:
    671                 case -EDESTADDRREQ:
    672                         goto next_server;
    673                 }
    674         }
    675 
    676 next_server:
    677         trace_afs_rotate(op, afs_rotate_trace_next_server, 0);
    678         _debug("next");
    679         op->estate = NULL;
    680         goto pick_server;
    681 
    682 no_more_servers:
    683         /* That's all the servers poked to no good effect.  Try again if some
    684          * of them were busy.
    685          */
    686         trace_afs_rotate(op, afs_rotate_trace_no_more_servers, 0);
    687         if (op->flags & AFS_OPERATION_VBUSY) {
    688                 afs_sleep_and_retry(op);
    689                 op->flags &= ~AFS_OPERATION_VBUSY;
    690                 goto restart_from_beginning;
    691         }
    692 
    693         rcu_read_lock();
    694         for (i = 0; i < op->server_list->nr_servers; i++) {
    695                 struct afs_endpoint_state *estate;
    696 
    697                 estate = op->server_states[i].endpoint_state;
    698                 error = READ_ONCE(estate->error);
    699                 if (error < 0)
    700                         afs_op_accumulate_error(op, error, estate->abort_code);
    701         }
    702         rcu_read_unlock();
    703 
    704 failed:
    705         trace_afs_rotate(op, afs_rotate_trace_failed, 0);
    706         op->flags |= AFS_OPERATION_STOP;
    707         op->estate = NULL;
    708         _leave(" = f [failed %d]", afs_op_error(op));
    709         return false;
    710 }

regards,
dan carpenter



More information about the linux-afs mailing list