diff options
-rw-r--r-- | fs/nfs/nfs4_fs.h | 3 | ||||
-rw-r--r-- | fs/nfs/nfs4proc.c | 154 | ||||
-rw-r--r-- | fs/nfs/nfs4state.c | 1 |
3 files changed, 123 insertions, 35 deletions
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index 78946c6ead88..fdcfbab886bb 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -161,6 +161,7 @@ enum { NFS_STATE_POSIX_LOCKS, /* Posix locks are supported */ NFS_STATE_RECOVERY_FAILED, /* OPEN stateid state recovery failed */ NFS_STATE_MAY_NOTIFY_LOCK, /* server may CB_NOTIFY_LOCK */ + NFS_STATE_CHANGE_WAIT, /* A state changing operation is outstanding */ }; struct nfs4_state { @@ -184,6 +185,8 @@ struct nfs4_state { unsigned int n_rdwr; /* Number of read/write references */ fmode_t state; /* State on the server (R,W, or RW) */ atomic_t count; + + wait_queue_head_t waitq; }; diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 82e5ed2ee6ba..cec4bcba65e8 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1378,6 +1378,25 @@ static bool nfs_open_stateid_recover_openmode(struct nfs4_state *state) } #endif /* CONFIG_NFS_V4_1 */ +static void nfs_state_log_update_open_stateid(struct nfs4_state *state) +{ + if (test_and_clear_bit(NFS_STATE_CHANGE_WAIT, &state->flags)) + wake_up_all(&state->waitq); +} + +static void nfs_state_log_out_of_order_open_stateid(struct nfs4_state *state, + const nfs4_stateid *stateid) +{ + u32 state_seqid = be32_to_cpu(state->open_stateid.seqid); + u32 stateid_seqid = be32_to_cpu(stateid->seqid); + + if (stateid_seqid == state_seqid + 1U || + (stateid_seqid == 1U && state_seqid == 0xffffffffU)) + nfs_state_log_update_open_stateid(state); + else + set_bit(NFS_STATE_CHANGE_WAIT, &state->flags); +} + static void nfs_test_and_clear_all_open_stateid(struct nfs4_state *state) { struct nfs_client *clp = state->owner->so_server->nfs_client; @@ -1393,18 +1412,32 @@ static void nfs_test_and_clear_all_open_stateid(struct nfs4_state *state) nfs4_state_mark_reclaim_nograce(clp, state); } +/* + * Check for whether or not the caller may update the open stateid + * to the value passed in by stateid. + * + * Note: This function relies heavily on the server implementing + * RFC7530 Section 9.1.4.2, and RFC5661 Section 8.2.2 + * correctly. + * i.e. The stateid seqids have to be initialised to 1, and + * are then incremented on every state transition. + */ static bool nfs_need_update_open_stateid(struct nfs4_state *state, - const nfs4_stateid *stateid, nfs4_stateid *freeme) + const nfs4_stateid *stateid) { - if (test_and_set_bit(NFS_OPEN_STATE, &state->flags) == 0) - return true; - if (!nfs4_stateid_match_other(stateid, &state->open_stateid)) { - nfs4_stateid_copy(freeme, &state->open_stateid); - nfs_test_and_clear_all_open_stateid(state); + if (test_bit(NFS_OPEN_STATE, &state->flags) == 0 || + !nfs4_stateid_match_other(stateid, &state->open_stateid)) { + if (stateid->seqid == cpu_to_be32(1)) + nfs_state_log_update_open_stateid(state); + else + set_bit(NFS_STATE_CHANGE_WAIT, &state->flags); return true; } - if (nfs4_stateid_is_newer(stateid, &state->open_stateid)) + + if (nfs4_stateid_is_newer(stateid, &state->open_stateid)) { + nfs_state_log_out_of_order_open_stateid(state, stateid); return true; + } return false; } @@ -1443,11 +1476,13 @@ static void nfs_clear_open_stateid_locked(struct nfs4_state *state, if (nfs4_stateid_match_other(stateid, &state->open_stateid) && !nfs4_stateid_is_newer(stateid, &state->open_stateid)) { nfs_resync_open_stateid_locked(state); - return; + goto out; } if (test_bit(NFS_DELEGATED_STATE, &state->flags) == 0) nfs4_stateid_copy(&state->stateid, stateid); nfs4_stateid_copy(&state->open_stateid, stateid); +out: + nfs_state_log_update_open_stateid(state); } static void nfs_clear_open_stateid(struct nfs4_state *state, @@ -1464,29 +1499,57 @@ static void nfs_clear_open_stateid(struct nfs4_state *state, } static void nfs_set_open_stateid_locked(struct nfs4_state *state, - const nfs4_stateid *stateid, fmode_t fmode, - nfs4_stateid *freeme) + const nfs4_stateid *stateid, nfs4_stateid *freeme) { - switch (fmode) { - case FMODE_READ: - set_bit(NFS_O_RDONLY_STATE, &state->flags); + DEFINE_WAIT(wait); + int status = 0; + for (;;) { + + if (!nfs_need_update_open_stateid(state, stateid)) + return; + if (!test_bit(NFS_STATE_CHANGE_WAIT, &state->flags)) break; - case FMODE_WRITE: - set_bit(NFS_O_WRONLY_STATE, &state->flags); + if (status) break; - case FMODE_READ|FMODE_WRITE: - set_bit(NFS_O_RDWR_STATE, &state->flags); + /* Rely on seqids for serialisation with NFSv4.0 */ + if (!nfs4_has_session(NFS_SERVER(state->inode)->nfs_client)) + break; + + prepare_to_wait(&state->waitq, &wait, TASK_KILLABLE); + /* + * Ensure we process the state changes in the same order + * in which the server processed them by delaying the + * update of the stateid until we are in sequence. + */ + write_sequnlock(&state->seqlock); + spin_unlock(&state->owner->so_lock); + rcu_read_unlock(); + if (!signal_pending(current)) { + if (schedule_timeout(5*HZ) == 0) + status = -EAGAIN; + else + status = 0; + } else + status = -EINTR; + finish_wait(&state->waitq, &wait); + rcu_read_lock(); + spin_lock(&state->owner->so_lock); + write_seqlock(&state->seqlock); } - if (!nfs_need_update_open_stateid(state, stateid, freeme)) - return; + + if (!nfs4_stateid_match_other(stateid, &state->open_stateid)) { + nfs4_stateid_copy(freeme, &state->open_stateid); + nfs_test_and_clear_all_open_stateid(state); + } + if (test_bit(NFS_DELEGATED_STATE, &state->flags) == 0) nfs4_stateid_copy(&state->stateid, stateid); nfs4_stateid_copy(&state->open_stateid, stateid); + nfs_state_log_update_open_stateid(state); } -static void __update_open_stateid(struct nfs4_state *state, +static void nfs_state_set_open_stateid(struct nfs4_state *state, const nfs4_stateid *open_stateid, - const nfs4_stateid *deleg_stateid, fmode_t fmode, nfs4_stateid *freeme) { @@ -1494,17 +1557,34 @@ static void __update_open_stateid(struct nfs4_state *state, * Protect the call to nfs4_state_set_mode_locked and * serialise the stateid update */ - spin_lock(&state->owner->so_lock); write_seqlock(&state->seqlock); - if (deleg_stateid != NULL) { - nfs4_stateid_copy(&state->stateid, deleg_stateid); - set_bit(NFS_DELEGATED_STATE, &state->flags); + nfs_set_open_stateid_locked(state, open_stateid, freeme); + switch (fmode) { + case FMODE_READ: + set_bit(NFS_O_RDONLY_STATE, &state->flags); + break; + case FMODE_WRITE: + set_bit(NFS_O_WRONLY_STATE, &state->flags); + break; + case FMODE_READ|FMODE_WRITE: + set_bit(NFS_O_RDWR_STATE, &state->flags); } - if (open_stateid != NULL) - nfs_set_open_stateid_locked(state, open_stateid, fmode, freeme); + set_bit(NFS_OPEN_STATE, &state->flags); + write_sequnlock(&state->seqlock); +} + +static void nfs_state_set_delegation(struct nfs4_state *state, + const nfs4_stateid *deleg_stateid, + fmode_t fmode) +{ + /* + * Protect the call to nfs4_state_set_mode_locked and + * serialise the stateid update + */ + write_seqlock(&state->seqlock); + nfs4_stateid_copy(&state->stateid, deleg_stateid); + set_bit(NFS_DELEGATED_STATE, &state->flags); write_sequnlock(&state->seqlock); - update_open_stateflags(state, fmode); - spin_unlock(&state->owner->so_lock); } static int update_open_stateid(struct nfs4_state *state, @@ -1522,6 +1602,12 @@ static int update_open_stateid(struct nfs4_state *state, fmode &= (FMODE_READ|FMODE_WRITE); rcu_read_lock(); + spin_lock(&state->owner->so_lock); + if (open_stateid != NULL) { + nfs_state_set_open_stateid(state, open_stateid, fmode, &freeme); + ret = 1; + } + deleg_cur = rcu_dereference(nfsi->delegation); if (deleg_cur == NULL) goto no_delegation; @@ -1538,18 +1624,16 @@ static int update_open_stateid(struct nfs4_state *state, goto no_delegation_unlock; nfs_mark_delegation_referenced(deleg_cur); - __update_open_stateid(state, open_stateid, &deleg_cur->stateid, - fmode, &freeme); + nfs_state_set_delegation(state, &deleg_cur->stateid, fmode); ret = 1; no_delegation_unlock: spin_unlock(&deleg_cur->lock); no_delegation: + if (ret) + update_open_stateflags(state, fmode); + spin_unlock(&state->owner->so_lock); rcu_read_unlock(); - if (!ret && open_stateid != NULL) { - __update_open_stateid(state, open_stateid, NULL, fmode, &freeme); - ret = 1; - } if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) nfs4_schedule_state_manager(clp); if (freeme.type != 0) diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 3bd79b8c016b..6e3f37288348 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -645,6 +645,7 @@ nfs4_alloc_open_state(void) INIT_LIST_HEAD(&state->lock_states); spin_lock_init(&state->state_lock); seqlock_init(&state->seqlock); + init_waitqueue_head(&state->waitq); return state; } |