[patch 10/10] Make set_fs_{root,pwd} take a struct path

jblunck
2007-09-27T14:13:03Z

[-- Attachment #1: nameidata-path-7.diff --]
[-- Type: text/plain, Size: 4839 bytes --]

In nearly all cases the set_fs_{root,pwd}() calls work on a struct
path. Change the function to reflect this and use path_get() here.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
---
fs/namespace.c | 26 ++++++++++++--------------
fs/open.c | 12 ++++--------
include/linux/fs_struct.h | 4 ++--
3 files changed, 18 insertions(+), 24 deletions(-)

Index: b/fs/namespace.c
===================================================================
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1580,15 +1580,13 @@ out1:
* Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values.
* It can block. Requires the big lock held.
*/
-void set_fs_root(struct fs_struct *fs, struct vfsmount *mnt,
- struct dentry *dentry)
+void set_fs_root(struct fs_struct *fs, struct path *path)
{
struct path old_root;

write_lock(&fs->lock);
old_root = fs->root;
- fs->root.mnt = mntget(mnt);
- fs->root.dentry = dget(dentry);
+ fs->root = *path_get(path);
write_unlock(&fs->lock);
if (old_root.dentry)
path_put(&old_root);
@@ -1598,15 +1596,13 @@ void set_fs_root(struct fs_struct *fs, s
* Replace the fs->{pwdmnt,pwd} with {mnt,dentry}. Put the old values.
* It can block. Requires the big lock held.
*/
-void set_fs_pwd(struct fs_struct *fs, struct vfsmount *mnt,
- struct dentry *dentry)
+void set_fs_pwd(struct fs_struct *fs, struct path *path)
{
struct path old_pwd;

write_lock(&fs->lock);
old_pwd = fs->pwd;
- fs->pwd.mnt = mntget(mnt);
- fs->pwd.dentry = dget(dentry);
+ fs->pwd = *path_get(path);
write_unlock(&fs->lock);

if (old_pwd.dentry)
@@ -1627,12 +1623,10 @@ static void chroot_fs_refs(struct nameid
task_unlock(p);
if (fs->root.dentry == old_nd->path.dentry
&& fs->root.mnt == old_nd->path.mnt)
- set_fs_root(fs, new_nd->path.mnt,
- new_nd->path.dentry);
+ set_fs_root(fs, &new_nd->path);
if (fs->pwd.dentry == old_nd->path.dentry
&& fs->pwd.mnt == old_nd->path.mnt)
- set_fs_pwd(fs, new_nd->path.mnt,
- new_nd->path.dentry);
+ set_fs_pwd(fs, &new_nd->path);
put_fs_struct(fs);
} else
task_unlock(p);
@@ -1774,6 +1768,7 @@ static void __init init_mount_tree(void)
{
struct vfsmount *mnt;
struct mnt_namespace *ns;
+ struct path root;

mnt = do_kern_mount("rootfs", 0, "rootfs", NULL);
if (IS_ERR(mnt))
@@ -1792,8 +1787,11 @@ static void __init init_mount_tree(void)
init_task.nsproxy->mnt_ns = ns;
get_mnt_ns(ns);

- set_fs_pwd(current->fs, ns->root, ns->root->mnt_root);
- set_fs_root(current->fs, ns->root, ns->root->mnt_root);
+ root.mnt = ns->root;
+ root.dentry = ns->root->mnt_root;
+
+ set_fs_pwd(current->fs, &root);
+ set_fs_root(current->fs, &root);
}

void __init mnt_init(unsigned long mempages)
Index: b/fs/open.c
===================================================================
--- a/fs/open.c
+++ b/fs/open.c
@@ -490,7 +490,7 @@ asmlinkage long sys_chdir(const char __u
if (error)
goto dput_and_out;

- set_fs_pwd(current->fs, nd.path.mnt, nd.path.dentry);
+ set_fs_pwd(current->fs, &nd.path);

dput_and_out:
path_put(&nd.path);
@@ -501,9 +501,7 @@ out:
asmlinkage long sys_fchdir(unsigned int fd)
{
struct file *file;
- struct dentry *dentry;
struct inode *inode;
- struct vfsmount *mnt;
int error;

error = -EBADF;
@@ -511,9 +509,7 @@ asmlinkage long sys_fchdir(unsigned int
if (!file)
goto out;

- dentry = file->f_path.dentry;
- mnt = file->f_path.mnt;
- inode = dentry->d_inode;
+ inode = file->f_path.dentry->d_inode;

error = -ENOTDIR;
if (!S_ISDIR(inode->i_mode))
@@ -521,7 +517,7 @@ asmlinkage long sys_fchdir(unsigned int

error = file_permission(file, MAY_EXEC);
if (!error)
- set_fs_pwd(current->fs, mnt, dentry);
+ set_fs_pwd(current->fs, &file->f_path);
out_putf:
fput(file);
out:
@@ -545,7 +541,7 @@ asmlinkage long sys_chroot(const char __
if (!capable(CAP_SYS_CHROOT))
goto dput_and_out;

- set_fs_root(current->fs, nd.path.mnt, nd.path.dentry);
+ set_fs_root(current->fs, &nd.path);
set_fs_altroot();
error = 0;
dput_and_out:
Index: b/include/linux/fs_struct.h
===================================================================
--- a/include/linux/fs_struct.h
+++ b/include/linux/fs_struct.h
@@ -20,8 +20,8 @@ extern struct kmem_cache *fs_cachep;

extern void exit_fs(struct task_struct *);
extern void set_fs_altroot(void);
-extern void set_fs_root(struct fs_struct *, struct vfsmount *, struct dentry *);
-extern void set_fs_pwd(struct fs_struct *, struct vfsmount *, struct dentry *);
+extern void set_fs_root(struct fs_struct *, struct path *);
+extern void set_fs_pwd(struct fs_struct *, struct path *);
extern struct fs_struct *copy_fs_struct(struct fs_struct *);
extern void put_fs_struct(struct fs_struct *);

--