From 9ad1aaa61522ffba001a5599623182fe23083a94 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 12 May 2015 16:44:39 -0400 Subject: [PATCH] namei: shift nameidata inside filename_lookup() pass root instead; non-NULL => copy to nd.root and set LOOKUP_ROOT in flags Signed-off-by: Al Viro --- fs/namei.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 847c61a48078..2999404c8d30 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2119,17 +2119,20 @@ static int path_lookupat(int dfd, const struct filename *name, unsigned flags, } static int filename_lookup(int dfd, struct filename *name, unsigned flags, - struct nameidata *nd, struct path *path) + struct path *path, struct path *root) { int retval; - struct nameidata *saved_nd = set_nameidata(nd); - - retval = path_lookupat(dfd, name, flags | LOOKUP_RCU, nd, path); + struct nameidata nd, *saved_nd = set_nameidata(&nd); + if (unlikely(root)) { + nd.root = *root; + flags |= LOOKUP_ROOT; + } + retval = path_lookupat(dfd, name, flags | LOOKUP_RCU, &nd, path); if (unlikely(retval == -ECHILD)) - retval = path_lookupat(dfd, name, flags, nd, path); + retval = path_lookupat(dfd, name, flags, &nd, path); if (unlikely(retval == -ESTALE)) retval = path_lookupat(dfd, name, flags | LOOKUP_REVAL, - nd, path); + &nd, path); if (likely(!retval)) audit_inode(name, path->dentry, flags & LOOKUP_PARENT); @@ -2209,11 +2212,10 @@ struct dentry *kern_path_locked(const char *name, struct path *path) int kern_path(const char *name, unsigned int flags, struct path *path) { - struct nameidata nd; struct filename *filename = getname_kernel(name); if (IS_ERR(filename)) return PTR_ERR(filename); - return filename_lookup(AT_FDCWD, filename, flags, &nd, path); + return filename_lookup(AT_FDCWD, filename, flags, path, NULL); } EXPORT_SYMBOL(kern_path); @@ -2229,7 +2231,7 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, const char *name, unsigned int flags, struct path *path) { - struct nameidata nd; + struct path root = {.mnt = mnt, .dentry = dentry}; struct filename *filename = getname_kernel(name); BUG_ON(flags & LOOKUP_PARENT); @@ -2237,11 +2239,8 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, if (IS_ERR(filename)) return PTR_ERR(filename); - nd.root.dentry = dentry; - nd.root.mnt = mnt; - /* the first argument of filename_lookup() is ignored with LOOKUP_ROOT */ - return filename_lookup(AT_FDCWD, filename, - flags | LOOKUP_ROOT, &nd, path); + /* the first argument of filename_lookup() is ignored with root */ + return filename_lookup(AT_FDCWD, filename, flags , path, &root); } EXPORT_SYMBOL(vfs_path_lookup); @@ -2299,14 +2298,13 @@ EXPORT_SYMBOL(lookup_one_len); int user_path_at_empty(int dfd, const char __user *name, unsigned flags, struct path *path, int *empty) { - struct nameidata nd; struct filename *tmp = getname_flags(name, flags, empty); if (IS_ERR(tmp)) return PTR_ERR(tmp); BUG_ON(flags & LOOKUP_PARENT); - return filename_lookup(dfd, tmp, flags, &nd, path); + return filename_lookup(dfd, tmp, flags, path, NULL); } int user_path_at(int dfd, const char __user *name, unsigned flags,