diff options
| -rw-r--r-- | Documentation/filesystems/nfs/localio.rst | 20 | ||||
| -rw-r--r-- | fs/nfs/nfs3proc.c | 46 | ||||
| -rw-r--r-- | fs/nfs_common/nfslocalio.c | 1 | ||||
| -rw-r--r-- | include/linux/nfslocalio.h | 3 |
4 files changed, 65 insertions, 5 deletions
diff --git a/Documentation/filesystems/nfs/localio.rst b/Documentation/filesystems/nfs/localio.rst index 7d2dbf75e96d..79808b37d745 100644 --- a/Documentation/filesystems/nfs/localio.rst +++ b/Documentation/filesystems/nfs/localio.rst @@ -291,7 +291,7 @@ align their IO). Security ======== -Localio is only supported when UNIX-style authentication (AUTH_UNIX, aka +LOCALIO is only supported when UNIX-style authentication (AUTH_UNIX, aka AUTH_SYS) is used. Care is taken to ensure the same NFS security mechanisms are used @@ -306,6 +306,24 @@ client is afforded this same level of access (albeit in terms of the NFS protocol via SUNRPC). No other namespaces (user, mount, etc) have been altered or purposely extended from the server to the client. +Module Parameters +================= + +/sys/module/nfs/parameters/localio_enabled (bool) +controls if LOCALIO is enabled, defaults to Y. If client and server are +local but 'localio_enabled' is set to N then LOCALIO will not be used. + +/sys/module/nfs/parameters/localio_O_DIRECT_semantics (bool) +controls if O_DIRECT extends down to the underlying filesystem, defaults +to N. Application IO must be logical blocksize aligned, otherwise +O_DIRECT will fail. + +/sys/module/nfsv3/parameters/nfs3_localio_probe_throttle (uint) +controls if NFSv3 read and write IOs will trigger (re)enabling of +LOCALIO every N (nfs3_localio_probe_throttle) IOs, defaults to 0 +(disabled). Must be power-of-2, admin keeps all the pieces if they +misconfigure (too low a value or non-power-of-2). + Testing ======= diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c index 1566163c6d85..7359e1a3bd84 100644 --- a/fs/nfs/nfs3proc.c +++ b/fs/nfs/nfs3proc.c @@ -844,6 +844,41 @@ nfs3_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle, return status; } +#if IS_ENABLED(CONFIG_NFS_LOCALIO) + +static unsigned nfs3_localio_probe_throttle __read_mostly = 0; +module_param(nfs3_localio_probe_throttle, uint, 0644); +MODULE_PARM_DESC(nfs3_localio_probe_throttle, + "Probe for NFSv3 LOCALIO every N IO requests. Must be power-of-2, defaults to 0 (probing disabled)."); + +static void nfs3_localio_probe(struct nfs_server *server) +{ + struct nfs_client *clp = server->nfs_client; + + /* Throttled to reduce nfs_local_probe_async() frequency */ + if (!nfs3_localio_probe_throttle || nfs_server_is_local(clp)) + return; + + /* + * Try (re)enabling LOCALIO if isn't enabled -- admin deems + * it worthwhile to periodically check if LOCALIO possible by + * setting the 'nfs3_localio_probe_throttle' module parameter. + * + * This is useful if LOCALIO was previously enabled, but was + * disabled due to server restart, and IO has successfully + * completed in terms of normal RPC. + */ + if ((clp->cl_uuid.nfs3_localio_probe_count++ & + (nfs3_localio_probe_throttle - 1)) == 0) { + if (!nfs_server_is_local(clp)) + nfs_local_probe_async(clp); + } +} + +#else +static void nfs3_localio_probe(struct nfs_server *server) {} +#endif + static int nfs3_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr) { struct inode *inode = hdr->inode; @@ -855,8 +890,11 @@ static int nfs3_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr) if (nfs3_async_handle_jukebox(task, inode)) return -EAGAIN; - if (task->tk_status >= 0 && !server->read_hdrsize) - cmpxchg(&server->read_hdrsize, 0, hdr->res.replen); + if (task->tk_status >= 0) { + if (!server->read_hdrsize) + cmpxchg(&server->read_hdrsize, 0, hdr->res.replen); + nfs3_localio_probe(server); + } nfs_invalidate_atime(inode); nfs_refresh_inode(inode, &hdr->fattr); @@ -886,8 +924,10 @@ static int nfs3_write_done(struct rpc_task *task, struct nfs_pgio_header *hdr) if (nfs3_async_handle_jukebox(task, inode)) return -EAGAIN; - if (task->tk_status >= 0) + if (task->tk_status >= 0) { nfs_writeback_update_inode(hdr); + nfs3_localio_probe(NFS_SERVER(inode)); + } return 0; } diff --git a/fs/nfs_common/nfslocalio.c b/fs/nfs_common/nfslocalio.c index bad7691e32b9..6a0bdea6d644 100644 --- a/fs/nfs_common/nfslocalio.c +++ b/fs/nfs_common/nfslocalio.c @@ -43,6 +43,7 @@ void nfs_uuid_init(nfs_uuid_t *nfs_uuid) INIT_LIST_HEAD(&nfs_uuid->list); INIT_LIST_HEAD(&nfs_uuid->files); spin_lock_init(&nfs_uuid->lock); + nfs_uuid->nfs3_localio_probe_count = 0; } EXPORT_SYMBOL_GPL(nfs_uuid_init); diff --git a/include/linux/nfslocalio.h b/include/linux/nfslocalio.h index 05817d6ef3d1..9aa8a43843d7 100644 --- a/include/linux/nfslocalio.h +++ b/include/linux/nfslocalio.h @@ -27,7 +27,8 @@ struct nfs_file_localio; */ typedef struct { uuid_t uuid; - /* sadly this struct is just over a cacheline, avoid bouncing */ + unsigned nfs3_localio_probe_count; + /* this struct is over a cacheline, avoid bouncing */ spinlock_t ____cacheline_aligned lock; struct list_head list; spinlock_t *list_lock; /* nn->local_clients_lock */ |