diff options
| -rw-r--r-- | fs/namei.c | 33 | ||||
| -rw-r--r-- | include/linux/namei.h | 2 |
2 files changed, 30 insertions, 5 deletions
diff --git a/fs/namei.c b/fs/namei.c index 3ef87d673bbe..1a1ea79a7ba0 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2267,6 +2267,33 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, EXPORT_SYMBOL(vfs_path_lookup); /** + * lookup_hash - lookup single pathname component on already hashed name + * @name: name and hash to lookup + * @base: base directory to lookup from + * + * The name must have been verified and hashed (see lookup_one_len()). Using + * this after just full_name_hash() is unsafe. + * + * This function also doesn't check for search permission on base directory. + * + * Use lookup_one_len_unlocked() instead, unless you really know what you are + * doing. + * + * Do not hold i_mutex; this helper takes i_mutex if necessary. + */ +struct dentry *lookup_hash(const struct qstr *name, struct dentry *base) +{ + struct dentry *ret; + + ret = lookup_dcache(name, base, 0); + if (!ret) + ret = lookup_slow(name, base, 0); + + return ret; +} +EXPORT_SYMBOL(lookup_hash); + +/** * lookup_one_len - filesystem helper to lookup single pathname component * @name: pathname component to lookup * @base: base directory to lookup from @@ -2337,7 +2364,6 @@ struct dentry *lookup_one_len_unlocked(const char *name, struct qstr this; unsigned int c; int err; - struct dentry *ret; this.name = name; this.len = len; @@ -2369,10 +2395,7 @@ struct dentry *lookup_one_len_unlocked(const char *name, if (err) return ERR_PTR(err); - ret = lookup_dcache(&this, base, 0); - if (!ret) - ret = lookup_slow(&this, base, 0); - return ret; + return lookup_hash(&this, base); } EXPORT_SYMBOL(lookup_one_len_unlocked); diff --git a/include/linux/namei.h b/include/linux/namei.h index 77d01700daf7..ec5ec2818a28 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -79,6 +79,8 @@ extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int); extern struct dentry *lookup_one_len(const char *, struct dentry *, int); extern struct dentry *lookup_one_len_unlocked(const char *, struct dentry *, int); +struct qstr; +extern struct dentry *lookup_hash(const struct qstr *, struct dentry *); extern int follow_down_one(struct path *); extern int follow_down(struct path *); |