From bf294b41cefcb22fc3139e0f42c5b3f06728bd5e Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 21 Feb 2011 11:05:41 -0800 Subject: SUNRPC: Close a race in __rpc_wait_for_completion_task() Although they run as rpciod background tasks, under normal operation (i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck() and nfs4_do_close() want to be fully synchronous. This means that when we exit, we want all references to the rpc_task to be gone, and we want any dentry references etc. held by that task to be released. For this reason these functions call __rpc_wait_for_completion_task(), followed by rpc_put_task() in the expectation that the latter will be releasing the last reference to the rpc_task, and thus ensuring that the callback_ops->rpc_release() has been called synchronously. This patch fixes a race which exists due to the fact that rpciod calls rpc_complete_task() (in order to wake up the callers of __rpc_wait_for_completion_task()) and then subsequently calls rpc_put_task() without ensuring that these two steps are done atomically. In order to avoid adding new spin locks, the patch uses the existing waitqueue spin lock to order the rpc_task reference count releases between the waiting process and rpciod. The common case where nobody is waiting for completion is optimised for by checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task reference count is 1: in those cases we drop trying to grab the spin lock, and immediately free up the rpc_task. Those few processes that need to put the rpc_task from inside an asynchronous context and that do not care about ordering are given a new helper: rpc_put_task_async(). Signed-off-by: Trond Myklebust --- include/linux/sunrpc/sched.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h index 88513fd8e208..d81db8012c63 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -212,6 +212,7 @@ struct rpc_task *rpc_run_task(const struct rpc_task_setup *); struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, const struct rpc_call_ops *ops); void rpc_put_task(struct rpc_task *); +void rpc_put_task_async(struct rpc_task *); void rpc_exit_task(struct rpc_task *); void rpc_exit(struct rpc_task *, int); void rpc_release_calldata(const struct rpc_call_ops *, void *); -- cgit v1.2.3-58-ga151 From 114f64b5f24abac33a42f4f1856eb3a9766d497e Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Wed, 9 Mar 2011 13:13:45 -0500 Subject: NFSv4: remove duplicate clientid in struct nfs_client Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust --- fs/nfs/nfs4xdr.c | 4 ++-- include/linux/nfs_fs_sb.h | 2 -- 2 files changed, 2 insertions(+), 4 deletions(-) (limited to 'include') diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 4e2c168b6ee9..94d50e86a124 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -1660,7 +1660,7 @@ static void encode_create_session(struct xdr_stream *xdr, p = reserve_space(xdr, 20 + 2*28 + 20 + len + 12); *p++ = cpu_to_be32(OP_CREATE_SESSION); - p = xdr_encode_hyper(p, clp->cl_ex_clid); + p = xdr_encode_hyper(p, clp->cl_clientid); *p++ = cpu_to_be32(clp->cl_seqid); /*Sequence id */ *p++ = cpu_to_be32(args->flags); /*flags */ @@ -4694,7 +4694,7 @@ static int decode_exchange_id(struct xdr_stream *xdr, p = xdr_inline_decode(xdr, 8); if (unlikely(!p)) goto out_overflow; - xdr_decode_hyper(p, &clp->cl_ex_clid); + xdr_decode_hyper(p, &clp->cl_clientid); p = xdr_inline_decode(xdr, 12); if (unlikely(!p)) goto out_overflow; diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index b197563913bf..6beb33e834ba 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -71,8 +71,6 @@ struct nfs_client { #endif /* CONFIG_NFS_V4 */ #ifdef CONFIG_NFS_V4_1 - /* clientid returned from EXCHANGE_ID, used by session operations */ - u64 cl_ex_clid; /* The sequence id to use for the next CREATE_SESSION */ u32 cl_seqid; /* The flags used for obtaining the clientid during EXCHANGE_ID */ -- cgit v1.2.3-58-ga151 From 0400a6b0cb756f976bae32ae8db47bfa9853897c Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Wed, 9 Mar 2011 16:00:53 -0500 Subject: NFSv4/4.1: Fix nfs4_schedule_state_recovery abuses nfs4_schedule_state_recovery() should only be used when we need to force the state manager to check the lease. If we just want to start the state manager in order to handle a state recovery situation, we should be using nfs4_schedule_state_manager(). This patch fixes the abuses of nfs4_schedule_state_recovery() by replacing its use with a set of helper functions that do the right thing. Signed-off-by: Trond Myklebust --- fs/nfs/nfs4_fs.h | 8 +++++++- fs/nfs/nfs4proc.c | 45 +++++++++++++++++++++++---------------------- fs/nfs/nfs4state.c | 25 +++++++++++++++++++------ include/linux/nfs_fs_sb.h | 8 +++----- 4 files changed, 52 insertions(+), 34 deletions(-) (limited to 'include') diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index 7a7474073148..54ff900cb8f0 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -298,6 +298,11 @@ struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp); #if defined(CONFIG_NFS_V4_1) struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp); struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp); +extern void nfs4_schedule_session_recovery(struct nfs4_session *); +#else +static inline void nfs4_schedule_session_recovery(struct nfs4_session *session) +{ +} #endif /* CONFIG_NFS_V4_1 */ extern struct nfs4_state_owner * nfs4_get_state_owner(struct nfs_server *, struct rpc_cred *); @@ -307,8 +312,9 @@ extern void nfs4_put_open_state(struct nfs4_state *); extern void nfs4_close_state(struct path *, struct nfs4_state *, fmode_t); extern void nfs4_close_sync(struct path *, struct nfs4_state *, fmode_t); extern void nfs4_state_set_mode_locked(struct nfs4_state *, fmode_t); -extern void nfs4_schedule_state_recovery(struct nfs_client *); +extern void nfs4_schedule_lease_recovery(struct nfs_client *); extern void nfs4_schedule_state_manager(struct nfs_client *); +extern void nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *); extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state); extern int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state); extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags); diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 0a13ae720dd0..411dc80d0656 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -257,12 +257,13 @@ static int nfs4_handle_exception(const struct nfs_server *server, int errorcode, case -NFS4ERR_OPENMODE: if (state == NULL) break; - nfs4_state_mark_reclaim_nograce(clp, state); - goto do_state_recovery; + nfs4_schedule_stateid_recovery(server, state); + goto wait_on_recovery; case -NFS4ERR_STALE_STATEID: case -NFS4ERR_STALE_CLIENTID: case -NFS4ERR_EXPIRED: - goto do_state_recovery; + nfs4_schedule_lease_recovery(clp); + goto wait_on_recovery; #if defined(CONFIG_NFS_V4_1) case -NFS4ERR_BADSESSION: case -NFS4ERR_BADSLOT: @@ -273,7 +274,7 @@ static int nfs4_handle_exception(const struct nfs_server *server, int errorcode, case -NFS4ERR_SEQ_MISORDERED: dprintk("%s ERROR: %d Reset session\n", __func__, errorcode); - nfs4_schedule_state_recovery(clp); + nfs4_schedule_session_recovery(clp->cl_session); exception->retry = 1; break; #endif /* defined(CONFIG_NFS_V4_1) */ @@ -296,8 +297,7 @@ static int nfs4_handle_exception(const struct nfs_server *server, int errorcode, } /* We failed to handle the error */ return nfs4_map_errors(ret); -do_state_recovery: - nfs4_schedule_state_recovery(clp); +wait_on_recovery: ret = nfs4_wait_clnt_recover(clp); if (ret == 0) exception->retry = 1; @@ -1256,14 +1256,13 @@ int nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs4_state case -NFS4ERR_BAD_HIGH_SLOT: case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: case -NFS4ERR_DEADSESSION: - nfs4_schedule_state_recovery( - server->nfs_client); + nfs4_schedule_session_recovery(server->nfs_client->cl_session); goto out; case -NFS4ERR_STALE_CLIENTID: case -NFS4ERR_STALE_STATEID: case -NFS4ERR_EXPIRED: /* Don't recall a delegation if it was lost */ - nfs4_schedule_state_recovery(server->nfs_client); + nfs4_schedule_lease_recovery(server->nfs_client); goto out; case -ERESTARTSYS: /* @@ -1272,7 +1271,7 @@ int nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs4_state */ case -NFS4ERR_ADMIN_REVOKED: case -NFS4ERR_BAD_STATEID: - nfs4_state_mark_reclaim_nograce(server->nfs_client, state); + nfs4_schedule_stateid_recovery(server, state); case -EKEYEXPIRED: /* * User RPCSEC_GSS context has expired. @@ -1588,7 +1587,7 @@ static int nfs4_recover_expired_lease(struct nfs_server *server) if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) && !test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state)) break; - nfs4_schedule_state_recovery(clp); + nfs4_schedule_state_manager(clp); ret = -EIO; } return ret; @@ -3179,7 +3178,7 @@ static void nfs4_renew_done(struct rpc_task *task, void *calldata) if (task->tk_status < 0) { /* Unless we're shutting down, schedule state recovery! */ if (test_bit(NFS_CS_RENEWD, &clp->cl_res_state) != 0) - nfs4_schedule_state_recovery(clp); + nfs4_schedule_lease_recovery(clp); return; } do_renew_lease(clp, timestamp); @@ -3504,12 +3503,13 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server, case -NFS4ERR_OPENMODE: if (state == NULL) break; - nfs4_state_mark_reclaim_nograce(clp, state); - goto do_state_recovery; + nfs4_schedule_stateid_recovery(server, state); + goto wait_on_recovery; case -NFS4ERR_STALE_STATEID: case -NFS4ERR_STALE_CLIENTID: case -NFS4ERR_EXPIRED: - goto do_state_recovery; + nfs4_schedule_lease_recovery(clp); + goto wait_on_recovery; #if defined(CONFIG_NFS_V4_1) case -NFS4ERR_BADSESSION: case -NFS4ERR_BADSLOT: @@ -3520,7 +3520,7 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server, case -NFS4ERR_SEQ_MISORDERED: dprintk("%s ERROR %d, Reset session\n", __func__, task->tk_status); - nfs4_schedule_state_recovery(clp); + nfs4_schedule_session_recovery(clp->cl_session); task->tk_status = 0; return -EAGAIN; #endif /* CONFIG_NFS_V4_1 */ @@ -3537,9 +3537,8 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server, } task->tk_status = nfs4_map_errors(task->tk_status); return 0; -do_state_recovery: +wait_on_recovery: rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL); - nfs4_schedule_state_recovery(clp); if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0) rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task); task->tk_status = 0; @@ -4406,12 +4405,14 @@ int nfs4_lock_delegation_recall(struct nfs4_state *state, struct file_lock *fl) case -NFS4ERR_EXPIRED: case -NFS4ERR_STALE_CLIENTID: case -NFS4ERR_STALE_STATEID: + nfs4_schedule_lease_recovery(server->nfs_client); + goto out; case -NFS4ERR_BADSESSION: case -NFS4ERR_BADSLOT: case -NFS4ERR_BAD_HIGH_SLOT: case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION: case -NFS4ERR_DEADSESSION: - nfs4_schedule_state_recovery(server->nfs_client); + nfs4_schedule_session_recovery(server->nfs_client->cl_session); goto out; case -ERESTARTSYS: /* @@ -4421,7 +4422,7 @@ int nfs4_lock_delegation_recall(struct nfs4_state *state, struct file_lock *fl) case -NFS4ERR_ADMIN_REVOKED: case -NFS4ERR_BAD_STATEID: case -NFS4ERR_OPENMODE: - nfs4_state_mark_reclaim_nograce(server->nfs_client, state); + nfs4_schedule_stateid_recovery(server, state); err = 0; goto out; case -EKEYEXPIRED: @@ -5150,7 +5151,7 @@ static int nfs41_sequence_handle_errors(struct rpc_task *task, struct nfs_client rpc_delay(task, NFS4_POLL_RETRY_MAX); return -EAGAIN; default: - nfs4_schedule_state_recovery(clp); + nfs4_schedule_lease_recovery(clp); } return 0; } @@ -5291,7 +5292,7 @@ static int nfs41_reclaim_complete_handle_errors(struct rpc_task *task, struct nf rpc_delay(task, NFS4_POLL_RETRY_MAX); return -EAGAIN; default: - nfs4_schedule_state_recovery(clp); + nfs4_schedule_lease_recovery(clp); } return 0; } diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index e6742b57a04c..47c8dcdada8a 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1007,9 +1007,9 @@ void nfs4_schedule_state_manager(struct nfs_client *clp) } /* - * Schedule a state recovery attempt + * Schedule a lease recovery attempt */ -void nfs4_schedule_state_recovery(struct nfs_client *clp) +void nfs4_schedule_lease_recovery(struct nfs_client *clp) { if (!clp) return; @@ -1041,6 +1041,14 @@ int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *s return 1; } +void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state) +{ + struct nfs_client *clp = server->nfs_client; + + nfs4_state_mark_reclaim_nograce(clp, state); + nfs4_schedule_state_manager(clp); +} + static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops) { struct inode *inode = state->inode; @@ -1436,10 +1444,15 @@ static int nfs4_reclaim_lease(struct nfs_client *clp) } #ifdef CONFIG_NFS_V4_1 +void nfs4_schedule_session_recovery(struct nfs4_session *session) +{ + nfs4_schedule_lease_recovery(session->clp); +} + void nfs41_handle_recall_slot(struct nfs_client *clp) { set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state); - nfs4_schedule_state_recovery(clp); + nfs4_schedule_state_manager(clp); } static void nfs4_reset_all_state(struct nfs_client *clp) @@ -1447,7 +1460,7 @@ static void nfs4_reset_all_state(struct nfs_client *clp) if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) { clp->cl_boot_time = CURRENT_TIME; nfs4_state_start_reclaim_nograce(clp); - nfs4_schedule_state_recovery(clp); + nfs4_schedule_state_manager(clp); } } @@ -1455,7 +1468,7 @@ static void nfs41_handle_server_reboot(struct nfs_client *clp) { if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) { nfs4_state_start_reclaim_reboot(clp); - nfs4_schedule_state_recovery(clp); + nfs4_schedule_state_manager(clp); } } @@ -1475,7 +1488,7 @@ static void nfs41_handle_cb_path_down(struct nfs_client *clp) { nfs_expire_all_delegations(clp); if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0) - nfs4_schedule_state_recovery(clp); + nfs4_schedule_state_manager(clp); } void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags) diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h index 6beb33e834ba..3e112de12d8d 100644 --- a/include/linux/nfs_fs_sb.h +++ b/include/linux/nfs_fs_sb.h @@ -68,9 +68,7 @@ struct nfs_client { unsigned char cl_id_uniquifier; u32 cl_cb_ident; /* v4.0 callback identifier */ const struct nfs4_minor_version_ops *cl_mvops; -#endif /* CONFIG_NFS_V4 */ -#ifdef CONFIG_NFS_V4_1 /* The sequence id to use for the next CREATE_SESSION */ u32 cl_seqid; /* The flags used for obtaining the clientid during EXCHANGE_ID */ @@ -78,7 +76,7 @@ struct nfs_client { struct nfs4_session *cl_session; /* sharred session */ struct list_head cl_layouts; struct pnfs_deviceid_cache *cl_devid_cache; /* pNFS deviceid cache */ -#endif /* CONFIG_NFS_V4_1 */ +#endif /* CONFIG_NFS_V4 */ #ifdef CONFIG_NFS_FSCACHE struct fscache_cookie *fscache; /* client index cache cookie */ @@ -183,7 +181,7 @@ struct nfs_server { /* maximum number of slots to use */ #define NFS4_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE -#if defined(CONFIG_NFS_V4_1) +#if defined(CONFIG_NFS_V4) /* Sessions */ #define SLOT_TABLE_SZ (NFS4_MAX_SLOT_TABLE/(8*sizeof(long))) @@ -223,5 +221,5 @@ struct nfs4_session { struct nfs_client *clp; }; -#endif /* CONFIG_NFS_V4_1 */ +#endif /* CONFIG_NFS_V4 */ #endif -- cgit v1.2.3-58-ga151