diff options
author | Christoph Hellwig <hch@infradead.org> | 2012-06-18 10:47:04 -0400 |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-07-14 16:35:40 +0400 |
commit | b5fb63c18315c5510c1d0636179c057e0c761c77 (patch) | |
tree | 19e42c9aa285eb64c277ece4083d4834351b3d5b | |
parent | 408ef013cc9e2f94a14f7ccbbe52ddfb18437a99 (diff) |
fs: add nd_jump_link
Add a helper that abstracts out the jump to an already parsed struct path
from ->follow_link operation from procfs. Not only does this clean up
the code by moving the two sides of this game into a single helper, but
it also prepares for making struct nameidata private to namei.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r-- | fs/namei.c | 27 | ||||
-rw-r--r-- | fs/proc/base.c | 3 | ||||
-rw-r--r-- | include/linux/namei.h | 2 |
3 files changed, 20 insertions, 12 deletions
diff --git a/fs/namei.c b/fs/namei.c index a9b94c62c303..0e1b9c3eb36d 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -586,6 +586,21 @@ static inline void path_to_nameidata(const struct path *path, nd->path.dentry = path->dentry; } +/* + * Helper to directly jump to a known parsed path from ->follow_link, + * caller must have taken a reference to path beforehand. + */ +void nd_jump_link(struct nameidata *nd, struct path *path) +{ + path_put(&nd->path); + + nd->path = *path; + nd->inode = nd->path.dentry->d_inode; + nd->flags |= LOOKUP_JUMPED; + + BUG_ON(nd->inode->i_op->follow_link); +} + static inline void put_link(struct nameidata *nd, struct path *link, void *cookie) { struct inode *inode = link->dentry->d_inode; @@ -630,17 +645,9 @@ follow_link(struct path *link, struct nameidata *nd, void **p) s = nd_get_link(nd); if (s) { error = __vfs_follow_link(nd, s); - } else if (nd->last_type == LAST_BIND) { - nd->flags |= LOOKUP_JUMPED; - nd->inode = nd->path.dentry->d_inode; - if (nd->inode->i_op->follow_link) { - /* stepped on a _really_ weird one */ - path_put(&nd->path); - error = -ELOOP; - } + if (unlikely(error)) + put_link(nd, link, *p); } - if (unlikely(error)) - put_link(nd, link, *p); return error; diff --git a/fs/proc/base.c b/fs/proc/base.c index 3bd5ac1ff018..2772208338f8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1438,8 +1438,7 @@ static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) if (error) goto out; - path_put(&nd->path); - nd->path = path; + nd_jump_link(nd, &path); return NULL; out: return ERR_PTR(error); diff --git a/include/linux/namei.h b/include/linux/namei.h index f5931489e150..d2ef8b34b967 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -80,6 +80,8 @@ extern int follow_up(struct path *); extern struct dentry *lock_rename(struct dentry *, struct dentry *); extern void unlock_rename(struct dentry *, struct dentry *); +extern void nd_jump_link(struct nameidata *nd, struct path *path); + static inline void nd_set_link(struct nameidata *nd, char *path) { nd->saved_names[nd->depth] = path; |