diff options
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/fs/namei.c b/fs/namei.c index efa592a98155..5fee8afa510e 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1672,13 +1672,15 @@ static inline int handle_mounts(struct nameidata *nd, struct dentry *dentry, path->dentry = dentry; if (nd->flags & LOOKUP_RCU) { unsigned int seq = nd->next_seq; + if (likely(!d_managed(dentry))) + return 0; if (likely(__follow_mount_rcu(nd, path))) return 0; // *path and nd->next_seq might've been clobbered path->mnt = nd->path.mnt; path->dentry = dentry; nd->next_seq = seq; - if (!try_to_unlazy_next(nd, dentry)) + if (unlikely(!try_to_unlazy_next(nd, dentry))) return -ECHILD; } ret = traverse_mounts(path, &jumped, &nd->total_link_count, nd->flags); @@ -1941,13 +1943,23 @@ static int reserve_stack(struct nameidata *nd, struct path *link) enum {WALK_TRAILING = 1, WALK_MORE = 2, WALK_NOFOLLOW = 4}; -static const char *pick_link(struct nameidata *nd, struct path *link, +static noinline const char *pick_link(struct nameidata *nd, struct path *link, struct inode *inode, int flags) { struct saved *last; const char *res; - int error = reserve_stack(nd, link); + int error; + + if (nd->flags & LOOKUP_RCU) { + /* make sure that d_is_symlink from step_into() matches the inode */ + if (read_seqcount_retry(&link->dentry->d_seq, nd->next_seq)) + return ERR_PTR(-ECHILD); + } else { + if (link->mnt == nd->path.mnt) + mntget(link->mnt); + } + error = reserve_stack(nd, link); if (unlikely(error)) { if (!(nd->flags & LOOKUP_RCU)) path_put(link); @@ -2026,9 +2038,10 @@ static const char *step_into(struct nameidata *nd, int flags, { struct path path; struct inode *inode; - int err = handle_mounts(nd, dentry, &path); + int err; - if (err < 0) + err = handle_mounts(nd, dentry, &path); + if (unlikely(err < 0)) return ERR_PTR(err); inode = path.dentry->d_inode; if (likely(!d_is_symlink(path.dentry)) || @@ -2050,14 +2063,6 @@ static const char *step_into(struct nameidata *nd, int flags, nd->seq = nd->next_seq; return NULL; } - if (nd->flags & LOOKUP_RCU) { - /* make sure that d_is_symlink above matches inode */ - if (read_seqcount_retry(&path.dentry->d_seq, nd->next_seq)) - return ERR_PTR(-ECHILD); - } else { - if (path.mnt == nd->path.mnt) - mntget(path.mnt); - } return pick_link(nd, &path, inode, flags); } |