diff options
Diffstat (limited to 'fs/nfs')
| -rw-r--r-- | fs/nfs/dir.c | 49 | ||||
| -rw-r--r-- | fs/nfs/file.c | 42 |
2 files changed, 76 insertions, 15 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 73f96acd5d3..ff6155f5e8d 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -528,19 +528,39 @@ static inline void nfs_renew_times(struct dentry * dentry) dentry->d_time = jiffies; } +/* + * Return the intent data that applies to this particular path component + * + * Note that the current set of intents only apply to the very last + * component of the path. + * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT. + */ +static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigned int mask) +{ + if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT)) + return 0; + return nd->flags & mask; +} + +/* + * Inode and filehandle revalidation for lookups. + * + * We force revalidation in the cases where the VFS sets LOOKUP_REVAL, + * or if the intent information indicates that we're about to open this + * particular file and the "nocto" mount flag is not set. + * + */ static inline int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd) { struct nfs_server *server = NFS_SERVER(inode); if (nd != NULL) { - int ndflags = nd->flags; /* VFS wants an on-the-wire revalidation */ - if (ndflags & LOOKUP_REVAL) + if (nd->flags & LOOKUP_REVAL) goto out_force; /* This is an open(2) */ - if ((ndflags & LOOKUP_OPEN) && - !(ndflags & LOOKUP_CONTINUE) && + if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 && !(server->flags & NFS_MOUNT_NOCTO)) goto out_force; } @@ -560,12 +580,8 @@ static inline int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { - int ndflags = 0; - - if (nd) - ndflags = nd->flags; /* Don't revalidate a negative dentry if we're creating a new file */ - if ((ndflags & LOOKUP_CREATE) && !(ndflags & LOOKUP_CONTINUE)) + if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0) return 0; return !nfs_check_verifier(dir, dentry); } @@ -700,12 +716,16 @@ struct dentry_operations nfs_dentry_operations = { .d_iput = nfs_dentry_iput, }; +/* + * Use intent information to check whether or not we're going to do + * an O_EXCL create using this path component. + */ static inline int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd) { if (NFS_PROTO(dir)->version == 2) return 0; - if (!nd || (nd->flags & LOOKUP_CONTINUE) || !(nd->flags & LOOKUP_CREATE)) + if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_CREATE) == 0) return 0; return (nd->intent.open.flags & O_EXCL) != 0; } @@ -772,12 +792,13 @@ struct dentry_operations nfs4_dentry_operations = { .d_iput = nfs_dentry_iput, }; +/* + * Use intent information to determine whether we need to substitute + * the NFSv4-style stateful OPEN for the LOOKUP call + */ static int is_atomic_open(struct inode *dir, struct nameidata *nd) { - if (!nd) - return 0; - /* Check that we are indeed trying to open this file */ - if ((nd->flags & LOOKUP_CONTINUE) || !(nd->flags & LOOKUP_OPEN)) + if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0) return 0; /* NFS does not (yet) have a stateful open for directories */ if (nd->flags & LOOKUP_DIRECTORY) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index f06eee6dcff..55c90759249 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -37,6 +37,7 @@ static int nfs_file_open(struct inode *, struct file *); static int nfs_file_release(struct inode *, struct file *); +static loff_t nfs_file_llseek(struct file *file, loff_t offset, int origin); static int nfs_file_mmap(struct file *, struct vm_area_struct *); static ssize_t nfs_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *); static ssize_t nfs_file_read(struct kiocb *, char __user *, size_t, loff_t); @@ -48,7 +49,7 @@ static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl); static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl); struct file_operations nfs_file_operations = { - .llseek = remote_llseek, + .llseek = nfs_file_llseek, .read = do_sync_read, .write = do_sync_write, .aio_read = nfs_file_read, @@ -114,6 +115,45 @@ nfs_file_release(struct inode *inode, struct file *filp) return NFS_PROTO(inode)->file_release(inode, filp); } +/** + * nfs_revalidate_size - Revalidate the file size + * @inode - pointer to inode struct + * @file - pointer to struct file + * + * Revalidates the file length. This is basically a wrapper around + * nfs_revalidate_inode() that takes into account the fact that we may + * have cached writes (in which case we don't care about the server's + * idea of what the file length is), or O_DIRECT (in which case we + * shouldn't trust the cache). + */ +static int nfs_revalidate_file_size(struct inode *inode, struct file *filp) +{ + struct nfs_server *server = NFS_SERVER(inode); + struct nfs_inode *nfsi = NFS_I(inode); + + if (server->flags & NFS_MOUNT_NOAC) + goto force_reval; + if (filp->f_flags & O_DIRECT) + goto force_reval; + if (nfsi->npages != 0) + return 0; + return nfs_revalidate_inode(server, inode); +force_reval: + return __nfs_revalidate_inode(server, inode); +} + +static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin) +{ + /* origin == SEEK_END => we must revalidate the cached file length */ + if (origin == 2) { + struct inode *inode = filp->f_mapping->host; + int retval = nfs_revalidate_file_size(inode, filp); + if (retval < 0) + return (loff_t)retval; + } + return remote_llseek(filp, offset, origin); +} + /* * Flush all dirty pages, and check for write errors. * |