diff options
Diffstat (limited to 'fs/nfsd/nfs4state.c')
| -rw-r--r-- | fs/nfsd/nfs4state.c | 237 |
1 files changed, 216 insertions, 21 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 39bfaba9c99c..9752beb78659 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -99,6 +99,7 @@ static struct kmem_cache *odstate_slab; static void free_session(struct nfsd4_session *); static const struct nfsd4_callback_ops nfsd4_cb_recall_ops; +static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops; static bool is_session_dead(struct nfsd4_session *ses) { @@ -210,6 +211,85 @@ static void nfsd4_put_session(struct nfsd4_session *ses) spin_unlock(&nn->client_lock); } +static struct nfsd4_blocked_lock * +find_blocked_lock(struct nfs4_lockowner *lo, struct knfsd_fh *fh, + struct nfsd_net *nn) +{ + struct nfsd4_blocked_lock *cur, *found = NULL; + + spin_lock(&nn->client_lock); + list_for_each_entry(cur, &lo->lo_blocked, nbl_list) { + if (fh_match(fh, &cur->nbl_fh)) { + list_del_init(&cur->nbl_list); + list_del_init(&cur->nbl_lru); + found = cur; + break; + } + } + spin_unlock(&nn->client_lock); + if (found) + posix_unblock_lock(&found->nbl_lock); + return found; +} + +static struct nfsd4_blocked_lock * +find_or_allocate_block(struct nfs4_lockowner *lo, struct knfsd_fh *fh, + struct nfsd_net *nn) +{ + struct nfsd4_blocked_lock *nbl; + + nbl = find_blocked_lock(lo, fh, nn); + if (!nbl) { + nbl= kmalloc(sizeof(*nbl), GFP_KERNEL); + if (nbl) { + fh_copy_shallow(&nbl->nbl_fh, fh); + locks_init_lock(&nbl->nbl_lock); + nfsd4_init_cb(&nbl->nbl_cb, lo->lo_owner.so_client, + &nfsd4_cb_notify_lock_ops, + NFSPROC4_CLNT_CB_NOTIFY_LOCK); + } + } + return nbl; +} + +static void +free_blocked_lock(struct nfsd4_blocked_lock *nbl) +{ + locks_release_private(&nbl->nbl_lock); + kfree(nbl); +} + +static int +nfsd4_cb_notify_lock_done(struct nfsd4_callback *cb, struct rpc_task *task) +{ + /* + * Since this is just an optimization, we don't try very hard if it + * turns out not to succeed. We'll requeue it on NFS4ERR_DELAY, and + * just quit trying on anything else. + */ + switch (task->tk_status) { + case -NFS4ERR_DELAY: + rpc_delay(task, 1 * HZ); + return 0; + default: + return 1; + } +} + +static void +nfsd4_cb_notify_lock_release(struct nfsd4_callback *cb) +{ + struct nfsd4_blocked_lock *nbl = container_of(cb, + struct nfsd4_blocked_lock, nbl_cb); + + free_blocked_lock(nbl); +} + +static const struct nfsd4_callback_ops nfsd4_cb_notify_lock_ops = { + .done = nfsd4_cb_notify_lock_done, + .release = nfsd4_cb_notify_lock_release, +}; + static inline struct nfs4_stateowner * nfs4_get_stateowner(struct nfs4_stateowner *sop) { @@ -3224,9 +3304,10 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, goto out; /* cases below refer to rfc 3530 section 14.2.34: */ if (!unconf || !same_verf(&confirm, &unconf->cl_confirm)) { - if (conf && !unconf) /* case 2: probable retransmit */ + if (conf && same_verf(&confirm, &conf->cl_confirm)) { + /* case 2: probable retransmit */ status = nfs_ok; - else /* case 4: client hasn't noticed we rebooted yet? */ + } else /* case 4: client hasn't noticed we rebooted yet? */ status = nfserr_stale_clientid; goto out; } @@ -4410,9 +4491,11 @@ out: * To finish the open response, we just need to set the rflags. */ open->op_rflags = NFS4_OPEN_RESULT_LOCKTYPE_POSIX; - if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED) && - !nfsd4_has_session(&resp->cstate)) + if (nfsd4_has_session(&resp->cstate)) + open->op_rflags |= NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK; + else if (!(open->op_openowner->oo_flags & NFS4_OO_CONFIRMED)) open->op_rflags |= NFS4_OPEN_RESULT_CONFIRM; + if (dp) nfs4_put_stid(&dp->dl_stid); if (stp) @@ -4501,6 +4584,7 @@ nfs4_laundromat(struct nfsd_net *nn) struct nfs4_openowner *oo; struct nfs4_delegation *dp; struct nfs4_ol_stateid *stp; + struct nfsd4_blocked_lock *nbl; struct list_head *pos, *next, reaplist; time_t cutoff = get_seconds() - nn->nfsd4_lease; time_t t, new_timeo = nn->nfsd4_lease; @@ -4569,6 +4653,41 @@ nfs4_laundromat(struct nfsd_net *nn) } spin_unlock(&nn->client_lock); + /* + * It's possible for a client to try and acquire an already held lock + * that is being held for a long time, and then lose interest in it. + * So, we clean out any un-revisited request after a lease period + * under the assumption that the client is no longer interested. + * + * RFC5661, sec. 9.6 states that the client must not rely on getting + * notifications and must continue to poll for locks, even when the + * server supports them. Thus this shouldn't lead to clients blocking + * indefinitely once the lock does become free. + */ + BUG_ON(!list_empty(&reaplist)); + spin_lock(&nn->client_lock); + while (!list_empty(&nn->blocked_locks_lru)) { + nbl = list_first_entry(&nn->blocked_locks_lru, + struct nfsd4_blocked_lock, nbl_lru); + if (time_after((unsigned long)nbl->nbl_time, + (unsigned long)cutoff)) { + t = nbl->nbl_time - cutoff; + new_timeo = min(new_timeo, t); + break; + } + list_move(&nbl->nbl_lru, &reaplist); + list_del_init(&nbl->nbl_list); + } + spin_unlock(&nn->client_lock); + + while (!list_empty(&reaplist)) { + nbl = list_first_entry(&nn->blocked_locks_lru, + struct nfsd4_blocked_lock, nbl_lru); + list_del_init(&nbl->nbl_lru); + posix_unblock_lock(&nbl->nbl_lock); + free_blocked_lock(nbl); + } + new_timeo = max_t(time_t, new_timeo, NFSD_LAUNDROMAT_MINTIMEOUT); return new_timeo; } @@ -5309,7 +5428,31 @@ nfsd4_fl_put_owner(fl_owner_t owner) nfs4_put_stateowner(&lo->lo_owner); } +static void +nfsd4_lm_notify(struct file_lock *fl) +{ + struct nfs4_lockowner *lo = (struct nfs4_lockowner *)fl->fl_owner; + struct net *net = lo->lo_owner.so_client->net; + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + struct nfsd4_blocked_lock *nbl = container_of(fl, + struct nfsd4_blocked_lock, nbl_lock); + bool queue = false; + + /* An empty list means that something else is going to be using it */ + spin_lock(&nn->client_lock); + if (!list_empty(&nbl->nbl_list)) { + list_del_init(&nbl->nbl_list); + list_del_init(&nbl->nbl_lru); + queue = true; + } + spin_unlock(&nn->client_lock); + + if (queue) + nfsd4_run_cb(&nbl->nbl_cb); +} + static const struct lock_manager_operations nfsd_posix_mng_ops = { + .lm_notify = nfsd4_lm_notify, .lm_get_owner = nfsd4_fl_get_owner, .lm_put_owner = nfsd4_fl_put_owner, }; @@ -5407,6 +5550,7 @@ alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp, lo = alloc_stateowner(lockowner_slab, &lock->lk_new_owner, clp); if (!lo) return NULL; + INIT_LIST_HEAD(&lo->lo_blocked); INIT_LIST_HEAD(&lo->lo_owner.so_stateids); lo->lo_owner.so_is_open_owner = 0; lo->lo_owner.so_seqid = lock->lk_new_lock_seqid; @@ -5588,12 +5732,15 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, struct nfs4_ol_stateid *open_stp = NULL; struct nfs4_file *fp; struct file *filp = NULL; + struct nfsd4_blocked_lock *nbl = NULL; struct file_lock *file_lock = NULL; struct file_lock *conflock = NULL; __be32 status = 0; int lkflg; int err; bool new = false; + unsigned char fl_type; + unsigned int fl_flags = FL_POSIX; struct net *net = SVC_NET(rqstp); struct nfsd_net *nn = net_generic(net, nfsd_net_id); @@ -5658,46 +5805,55 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (!locks_in_grace(net) && lock->lk_reclaim) goto out; - file_lock = locks_alloc_lock(); - if (!file_lock) { - dprintk("NFSD: %s: unable to allocate lock!\n", __func__); - status = nfserr_jukebox; - goto out; - } - fp = lock_stp->st_stid.sc_file; switch (lock->lk_type) { - case NFS4_READ_LT: case NFS4_READW_LT: + if (nfsd4_has_session(cstate)) + fl_flags |= FL_SLEEP; + /* Fallthrough */ + case NFS4_READ_LT: spin_lock(&fp->fi_lock); filp = find_readable_file_locked(fp); if (filp) get_lock_access(lock_stp, NFS4_SHARE_ACCESS_READ); spin_unlock(&fp->fi_lock); - file_lock->fl_type = F_RDLCK; + fl_type = F_RDLCK; break; - case NFS4_WRITE_LT: case NFS4_WRITEW_LT: + if (nfsd4_has_session(cstate)) + fl_flags |= FL_SLEEP; + /* Fallthrough */ + case NFS4_WRITE_LT: spin_lock(&fp->fi_lock); filp = find_writeable_file_locked(fp); if (filp) get_lock_access(lock_stp, NFS4_SHARE_ACCESS_WRITE); spin_unlock(&fp->fi_lock); - file_lock->fl_type = F_WRLCK; + fl_type = F_WRLCK; break; default: status = nfserr_inval; goto out; } + if (!filp) { status = nfserr_openmode; goto out; } + nbl = find_or_allocate_block(lock_sop, &fp->fi_fhandle, nn); + if (!nbl) { + dprintk("NFSD: %s: unable to allocate block!\n", __func__); + status = nfserr_jukebox; + goto out; + } + + file_lock = &nbl->nbl_lock; + file_lock->fl_type = fl_type; file_lock->fl_owner = (fl_owner_t)lockowner(nfs4_get_stateowner(&lock_sop->lo_owner)); file_lock->fl_pid = current->tgid; file_lock->fl_file = filp; - file_lock->fl_flags = FL_POSIX; + file_lock->fl_flags = fl_flags; file_lock->fl_lmops = &nfsd_posix_mng_ops; file_lock->fl_start = lock->lk_offset; file_lock->fl_end = last_byte_offset(lock->lk_offset, lock->lk_length); @@ -5710,18 +5866,29 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, goto out; } + if (fl_flags & FL_SLEEP) { + nbl->nbl_time = jiffies; + spin_lock(&nn->client_lock); + list_add_tail(&nbl->nbl_list, &lock_sop->lo_blocked); + list_add_tail(&nbl->nbl_lru, &nn->blocked_locks_lru); + spin_unlock(&nn->client_lock); + } + err = vfs_lock_file(filp, F_SETLK, file_lock, conflock); - switch (-err) { + switch (err) { case 0: /* success! */ nfs4_inc_and_copy_stateid(&lock->lk_resp_stateid, &lock_stp->st_stid); status = 0; break; - case (EAGAIN): /* conflock holds conflicting lock */ + case FILE_LOCK_DEFERRED: + nbl = NULL; + /* Fallthrough */ + case -EAGAIN: /* conflock holds conflicting lock */ status = nfserr_denied; dprintk("NFSD: nfsd4_lock: conflicting lock found!\n"); nfs4_set_lock_denied(conflock, &lock->lk_denied); break; - case (EDEADLK): + case -EDEADLK: status = nfserr_deadlock; break; default: @@ -5730,6 +5897,16 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, break; } out: + if (nbl) { + /* dequeue it if we queued it before */ + if (fl_flags & FL_SLEEP) { + spin_lock(&nn->client_lock); + list_del_init(&nbl->nbl_list); + list_del_init(&nbl->nbl_lru); + spin_unlock(&nn->client_lock); + } + free_blocked_lock(nbl); + } if (filp) fput(filp); if (lock_stp) { @@ -5753,8 +5930,6 @@ out: if (open_stp) nfs4_put_stid(&open_stp->st_stid); nfsd4_bump_seqid(cstate, status); - if (file_lock) - locks_free_lock(file_lock); if (conflock) locks_free_lock(conflock); return status; @@ -6768,6 +6943,7 @@ static int nfs4_state_create_net(struct net *net) INIT_LIST_HEAD(&nn->client_lru); INIT_LIST_HEAD(&nn->close_lru); INIT_LIST_HEAD(&nn->del_recall_lru); + INIT_LIST_HEAD(&nn->blocked_locks_lru); spin_lock_init(&nn->client_lock); INIT_DELAYED_WORK(&nn->laundromat_work, laundromat_main); @@ -6865,6 +7041,7 @@ nfs4_state_shutdown_net(struct net *net) struct nfs4_delegation *dp = NULL; struct list_head *pos, *next, reaplist; struct nfsd_net *nn = net_generic(net, nfsd_net_id); + struct nfsd4_blocked_lock *nbl; cancel_delayed_work_sync(&nn->laundromat_work); locks_end_grace(&nn->nfsd4_manager); @@ -6885,6 +7062,24 @@ nfs4_state_shutdown_net(struct net *net) nfs4_put_stid(&dp->dl_stid); } + BUG_ON(!list_empty(&reaplist)); + spin_lock(&nn->client_lock); + while (!list_empty(&nn->blocked_locks_lru)) { + nbl = list_first_entry(&nn->blocked_locks_lru, + struct nfsd4_blocked_lock, nbl_lru); + list_move(&nbl->nbl_lru, &reaplist); + list_del_init(&nbl->nbl_list); + } + spin_unlock(&nn->client_lock); + + while (!list_empty(&reaplist)) { + nbl = list_first_entry(&nn->blocked_locks_lru, + struct nfsd4_blocked_lock, nbl_lru); + list_del_init(&nbl->nbl_lru); + posix_unblock_lock(&nbl->nbl_lock); + free_blocked_lock(nbl); + } + nfsd4_client_tracking_exit(net); nfs4_state_destroy_net(net); } |