diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2011-03-04 14:39:30 -0500 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2011-03-14 09:15:25 -0400 |
| commit | a7472baba22dd5d68580f528374f93421b33667e (patch) | |
| tree | a7919a0dea2c58fa498e17d6c7be19fb0b9b571f | |
| parent | ef7562d5283a91da3ba5c14de3221f47b7f08823 (diff) | |
make nameidata_dentry_drop_rcu_maybe() always leave RCU mode
Now we have do_follow_link() guaranteed to leave without dangling RCU
and the next step will get LOOKUP_RCU logics completely out of
link_path_walk().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | fs/namei.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/fs/namei.c b/fs/namei.c index ea14bfb04785..53bba7c1a520 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -498,8 +498,15 @@ err_root: /* Try to drop out of rcu-walk mode if we were in it, otherwise do nothing. */ static inline int nameidata_dentry_drop_rcu_maybe(struct nameidata *nd, struct dentry *dentry) { - if (nd->flags & LOOKUP_RCU) - return nameidata_dentry_drop_rcu(nd, dentry); + if (nd->flags & LOOKUP_RCU) { + if (unlikely(nameidata_dentry_drop_rcu(nd, dentry))) { + nd->flags &= ~LOOKUP_RCU; + nd->root.mnt = NULL; + rcu_read_unlock(); + br_read_unlock(vfsmount_lock); + return -ECHILD; + } + } return 0; } @@ -1424,7 +1431,7 @@ static int link_path_walk(const char *name, struct nameidata *nd) if (inode && inode->i_op->follow_link) { err = do_follow_link(inode, &next, nd); if (err) - goto return_err; + return err; nd->inode = nd->path.dentry->d_inode; } else { path_to_nameidata(&next, nd); @@ -1455,7 +1462,7 @@ last_component: (lookup_flags & LOOKUP_FOLLOW)) { err = do_follow_link(inode, &next, nd); if (err) - goto return_err; + return err; nd->inode = nd->path.dentry->d_inode; } else { path_to_nameidata(&next, nd); @@ -1477,7 +1484,6 @@ lookup_parent: } if (!(nd->flags & LOOKUP_RCU)) path_put(&nd->path); -return_err: if (nd->flags & LOOKUP_RCU) { nd->flags &= ~LOOKUP_RCU; nd->root.mnt = NULL; |