Embed a struct path into struct nameidata instead of nd->{dentry,mnt}
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/namei.c b/fs/namei.c
index 3ed4d75..c9b05a7 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -231,7 +231,7 @@
struct vfsmount *mnt = NULL;
if (nd)
- mnt = nd->mnt;
+ mnt = nd->path.mnt;
if (mask & MAY_WRITE) {
umode_t mode = inode->i_mode;
@@ -296,7 +296,7 @@
*/
int vfs_permission(struct nameidata *nd, int mask)
{
- return permission(nd->dentry->d_inode, mask, nd);
+ return permission(nd->path.dentry->d_inode, mask, nd);
}
/**
@@ -364,8 +364,8 @@
void path_release(struct nameidata *nd)
{
- dput(nd->dentry);
- mntput(nd->mnt);
+ dput(nd->path.dentry);
+ mntput(nd->path.mnt);
}
/**
@@ -530,15 +530,15 @@
read_lock(&fs->lock);
if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->mnt = mntget(fs->altrootmnt);
- nd->dentry = dget(fs->altroot);
+ nd->path.mnt = mntget(fs->altrootmnt);
+ nd->path.dentry = dget(fs->altroot);
read_unlock(&fs->lock);
if (__emul_lookup_dentry(name,nd))
return 0;
read_lock(&fs->lock);
}
- nd->mnt = mntget(fs->rootmnt);
- nd->dentry = dget(fs->root);
+ nd->path.mnt = mntget(fs->rootmnt);
+ nd->path.dentry = dget(fs->root);
read_unlock(&fs->lock);
return 1;
}
@@ -581,17 +581,17 @@
static inline void dput_path(struct path *path, struct nameidata *nd)
{
dput(path->dentry);
- if (path->mnt != nd->mnt)
+ if (path->mnt != nd->path.mnt)
mntput(path->mnt);
}
static inline void path_to_nameidata(struct path *path, struct nameidata *nd)
{
- dput(nd->dentry);
- if (nd->mnt != path->mnt)
- mntput(nd->mnt);
- nd->mnt = path->mnt;
- nd->dentry = path->dentry;
+ dput(nd->path.dentry);
+ if (nd->path.mnt != path->mnt)
+ mntput(nd->path.mnt);
+ nd->path.mnt = path->mnt;
+ nd->path.dentry = path->dentry;
}
static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd)
@@ -603,7 +603,7 @@
touch_atime(path->mnt, dentry);
nd_set_link(nd, NULL);
- if (path->mnt != nd->mnt) {
+ if (path->mnt != nd->path.mnt) {
path_to_nameidata(path, nd);
dget(dentry);
}
@@ -733,37 +733,37 @@
while(1) {
struct vfsmount *parent;
- struct dentry *old = nd->dentry;
+ struct dentry *old = nd->path.dentry;
read_lock(&fs->lock);
- if (nd->dentry == fs->root &&
- nd->mnt == fs->rootmnt) {
+ if (nd->path.dentry == fs->root &&
+ nd->path.mnt == fs->rootmnt) {
read_unlock(&fs->lock);
break;
}
read_unlock(&fs->lock);
spin_lock(&dcache_lock);
- if (nd->dentry != nd->mnt->mnt_root) {
- nd->dentry = dget(nd->dentry->d_parent);
+ if (nd->path.dentry != nd->path.mnt->mnt_root) {
+ nd->path.dentry = dget(nd->path.dentry->d_parent);
spin_unlock(&dcache_lock);
dput(old);
break;
}
spin_unlock(&dcache_lock);
spin_lock(&vfsmount_lock);
- parent = nd->mnt->mnt_parent;
- if (parent == nd->mnt) {
+ parent = nd->path.mnt->mnt_parent;
+ if (parent == nd->path.mnt) {
spin_unlock(&vfsmount_lock);
break;
}
mntget(parent);
- nd->dentry = dget(nd->mnt->mnt_mountpoint);
+ nd->path.dentry = dget(nd->path.mnt->mnt_mountpoint);
spin_unlock(&vfsmount_lock);
dput(old);
- mntput(nd->mnt);
- nd->mnt = parent;
+ mntput(nd->path.mnt);
+ nd->path.mnt = parent;
}
- follow_mount(&nd->mnt, &nd->dentry);
+ follow_mount(&nd->path.mnt, &nd->path.dentry);
}
/*
@@ -774,8 +774,8 @@
static int do_lookup(struct nameidata *nd, struct qstr *name,
struct path *path)
{
- struct vfsmount *mnt = nd->mnt;
- struct dentry *dentry = __d_lookup(nd->dentry, name);
+ struct vfsmount *mnt = nd->path.mnt;
+ struct dentry *dentry = __d_lookup(nd->path.dentry, name);
if (!dentry)
goto need_lookup;
@@ -788,7 +788,7 @@
return 0;
need_lookup:
- dentry = real_lookup(nd->dentry, name, nd);
+ dentry = real_lookup(nd->path.dentry, name, nd);
if (IS_ERR(dentry))
goto fail;
goto done;
@@ -825,7 +825,7 @@
if (!*name)
goto return_reval;
- inode = nd->dentry->d_inode;
+ inode = nd->path.dentry->d_inode;
if (nd->depth)
lookup_flags = LOOKUP_FOLLOW | (nd->flags & LOOKUP_CONTINUE);
@@ -873,7 +873,7 @@
if (this.name[1] != '.')
break;
follow_dotdot(nd);
- inode = nd->dentry->d_inode;
+ inode = nd->path.dentry->d_inode;
/* fallthrough */
case 1:
continue;
@@ -882,8 +882,9 @@
* See if the low-level filesystem might want
* to use its own hash..
*/
- if (nd->dentry->d_op && nd->dentry->d_op->d_hash) {
- err = nd->dentry->d_op->d_hash(nd->dentry, &this);
+ if (nd->path.dentry->d_op && nd->path.dentry->d_op->d_hash) {
+ err = nd->path.dentry->d_op->d_hash(nd->path.dentry,
+ &this);
if (err < 0)
break;
}
@@ -905,7 +906,7 @@
if (err)
goto return_err;
err = -ENOENT;
- inode = nd->dentry->d_inode;
+ inode = nd->path.dentry->d_inode;
if (!inode)
break;
err = -ENOTDIR;
@@ -933,13 +934,14 @@
if (this.name[1] != '.')
break;
follow_dotdot(nd);
- inode = nd->dentry->d_inode;
+ inode = nd->path.dentry->d_inode;
/* fallthrough */
case 1:
goto return_reval;
}
- if (nd->dentry->d_op && nd->dentry->d_op->d_hash) {
- err = nd->dentry->d_op->d_hash(nd->dentry, &this);
+ if (nd->path.dentry->d_op && nd->path.dentry->d_op->d_hash) {
+ err = nd->path.dentry->d_op->d_hash(nd->path.dentry,
+ &this);
if (err < 0)
break;
}
@@ -952,7 +954,7 @@
err = do_follow_link(&next, nd);
if (err)
goto return_err;
- inode = nd->dentry->d_inode;
+ inode = nd->path.dentry->d_inode;
} else
path_to_nameidata(&next, nd);
err = -ENOENT;
@@ -980,11 +982,12 @@
* We bypassed the ordinary revalidation routines.
* We may need to check the cached dentry for staleness.
*/
- if (nd->dentry && nd->dentry->d_sb &&
- (nd->dentry->d_sb->s_type->fs_flags & FS_REVAL_DOT)) {
+ if (nd->path.dentry && nd->path.dentry->d_sb &&
+ (nd->path.dentry->d_sb->s_type->fs_flags & FS_REVAL_DOT)) {
err = -ESTALE;
/* Note: we do not d_invalidate() */
- if (!nd->dentry->d_op->d_revalidate(nd->dentry, nd))
+ if (!nd->path.dentry->d_op->d_revalidate(
+ nd->path.dentry, nd))
break;
}
return_base:
@@ -1011,20 +1014,20 @@
int result;
/* make sure the stuff we saved doesn't go away */
- dget(save.dentry);
- mntget(save.mnt);
+ dget(save.path.dentry);
+ mntget(save.path.mnt);
result = __link_path_walk(name, nd);
if (result == -ESTALE) {
*nd = save;
- dget(nd->dentry);
- mntget(nd->mnt);
+ dget(nd->path.dentry);
+ mntget(nd->path.mnt);
nd->flags |= LOOKUP_REVAL;
result = __link_path_walk(name, nd);
}
- dput(save.dentry);
- mntput(save.mnt);
+ dput(save.path.dentry);
+ mntput(save.path.mnt);
return result;
}
@@ -1044,9 +1047,10 @@
if (path_walk(name, nd))
return 0; /* something went wrong... */
- if (!nd->dentry->d_inode || S_ISDIR(nd->dentry->d_inode->i_mode)) {
- struct dentry *old_dentry = nd->dentry;
- struct vfsmount *old_mnt = nd->mnt;
+ if (!nd->path.dentry->d_inode ||
+ S_ISDIR(nd->path.dentry->d_inode->i_mode)) {
+ struct dentry *old_dentry = nd->path.dentry;
+ struct vfsmount *old_mnt = nd->path.mnt;
struct qstr last = nd->last;
int last_type = nd->last_type;
struct fs_struct *fs = current->fs;
@@ -1057,19 +1061,19 @@
*/
nd->last_type = LAST_ROOT;
read_lock(&fs->lock);
- nd->mnt = mntget(fs->rootmnt);
- nd->dentry = dget(fs->root);
+ nd->path.mnt = mntget(fs->rootmnt);
+ nd->path.dentry = dget(fs->root);
read_unlock(&fs->lock);
if (path_walk(name, nd) == 0) {
- if (nd->dentry->d_inode) {
+ if (nd->path.dentry->d_inode) {
dput(old_dentry);
mntput(old_mnt);
return 1;
}
path_release(nd);
}
- nd->dentry = old_dentry;
- nd->mnt = old_mnt;
+ nd->path.dentry = old_dentry;
+ nd->path.mnt = old_mnt;
nd->last = last;
nd->last_type = last_type;
}
@@ -1089,8 +1093,8 @@
goto set_it;
err = path_lookup(emul, LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_NOALT, &nd);
if (!err) {
- mnt = nd.mnt;
- dentry = nd.dentry;
+ mnt = nd.path.mnt;
+ dentry = nd.path.dentry;
}
set_it:
write_lock(&fs->lock);
@@ -1121,20 +1125,20 @@
if (*name=='/') {
read_lock(&fs->lock);
if (fs->altroot && !(nd->flags & LOOKUP_NOALT)) {
- nd->mnt = mntget(fs->altrootmnt);
- nd->dentry = dget(fs->altroot);
+ nd->path.mnt = mntget(fs->altrootmnt);
+ nd->path.dentry = dget(fs->altroot);
read_unlock(&fs->lock);
if (__emul_lookup_dentry(name,nd))
goto out; /* found in altroot */
read_lock(&fs->lock);
}
- nd->mnt = mntget(fs->rootmnt);
- nd->dentry = dget(fs->root);
+ nd->path.mnt = mntget(fs->rootmnt);
+ nd->path.dentry = dget(fs->root);
read_unlock(&fs->lock);
} else if (dfd == AT_FDCWD) {
read_lock(&fs->lock);
- nd->mnt = mntget(fs->pwdmnt);
- nd->dentry = dget(fs->pwd);
+ nd->path.mnt = mntget(fs->pwdmnt);
+ nd->path.dentry = dget(fs->pwd);
read_unlock(&fs->lock);
} else {
struct dentry *dentry;
@@ -1154,17 +1158,17 @@
if (retval)
goto fput_fail;
- nd->mnt = mntget(file->f_path.mnt);
- nd->dentry = dget(dentry);
+ nd->path.mnt = mntget(file->f_path.mnt);
+ nd->path.dentry = dget(dentry);
fput_light(file, fput_needed);
}
retval = path_walk(name, nd);
out:
- if (unlikely(!retval && !audit_dummy_context() && nd->dentry &&
- nd->dentry->d_inode))
- audit_inode(name, nd->dentry);
+ if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
+ nd->path.dentry->d_inode))
+ audit_inode(name, nd->path.dentry);
out_fail:
return retval;
@@ -1198,13 +1202,13 @@
nd->flags = flags;
nd->depth = 0;
- nd->mnt = mntget(mnt);
- nd->dentry = dget(dentry);
+ nd->path.mnt = mntget(mnt);
+ nd->path.dentry = dget(dentry);
retval = path_walk(name, nd);
- if (unlikely(!retval && !audit_dummy_context() && nd->dentry &&
- nd->dentry->d_inode))
- audit_inode(name, nd->dentry);
+ if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry &&
+ nd->path.dentry->d_inode))
+ audit_inode(name, nd->path.dentry);
return retval;
@@ -1323,10 +1327,10 @@
{
int err;
- err = permission(nd->dentry->d_inode, MAY_EXEC, nd);
+ err = permission(nd->path.dentry->d_inode, MAY_EXEC, nd);
if (err)
return ERR_PTR(err);
- return __lookup_hash(&nd->last, nd->dentry, nd);
+ return __lookup_hash(&nd->last, nd->path.dentry, nd);
}
static int __lookup_one_len(const char *name, struct qstr *this,
@@ -1585,7 +1589,7 @@
int may_open(struct nameidata *nd, int acc_mode, int flag)
{
- struct dentry *dentry = nd->dentry;
+ struct dentry *dentry = nd->path.dentry;
struct inode *inode = dentry->d_inode;
int error;
@@ -1606,7 +1610,7 @@
if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
flag &= ~O_TRUNC;
} else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
- if (nd->mnt->mnt_flags & MNT_NODEV)
+ if (nd->path.mnt->mnt_flags & MNT_NODEV)
return -EACCES;
flag &= ~O_TRUNC;
@@ -1668,14 +1672,14 @@
int flag, int mode)
{
int error;
- struct dentry *dir = nd->dentry;
+ struct dentry *dir = nd->path.dentry;
if (!IS_POSIXACL(dir->d_inode))
mode &= ~current->fs->umask;
error = vfs_create(dir->d_inode, path->dentry, mode, nd);
mutex_unlock(&dir->d_inode->i_mutex);
- dput(nd->dentry);
- nd->dentry = path->dentry;
+ dput(nd->path.dentry);
+ nd->path.dentry = path->dentry;
if (error)
return error;
/* Don't check for write permission, don't truncate */
@@ -1742,11 +1746,11 @@
if (nd->last_type != LAST_NORM || nd->last.name[nd->last.len])
goto exit;
- dir = nd->dentry;
+ dir = nd->path.dentry;
nd->flags &= ~LOOKUP_PARENT;
mutex_lock(&dir->d_inode->i_mutex);
path.dentry = lookup_hash(nd);
- path.mnt = nd->mnt;
+ path.mnt = nd->path.mnt;
do_last:
error = PTR_ERR(path.dentry);
@@ -1851,10 +1855,10 @@
__putname(nd->last.name);
goto exit;
}
- dir = nd->dentry;
+ dir = nd->path.dentry;
mutex_lock(&dir->d_inode->i_mutex);
path.dentry = lookup_hash(nd);
- path.mnt = nd->mnt;
+ path.mnt = nd->path.mnt;
__putname(nd->last.name);
goto do_last;
}
@@ -1867,13 +1871,13 @@
* Simple function to lookup and return a dentry and create it
* if it doesn't exist. Is SMP-safe.
*
- * Returns with nd->dentry->d_inode->i_mutex locked.
+ * Returns with nd->path.dentry->d_inode->i_mutex locked.
*/
struct dentry *lookup_create(struct nameidata *nd, int is_dir)
{
struct dentry *dentry = ERR_PTR(-EEXIST);
- mutex_lock_nested(&nd->dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&nd->path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
/*
* Yucky last component or no last component at all?
* (foo/., foo/.., /////)
@@ -1952,19 +1956,19 @@
dentry = lookup_create(&nd, 0);
error = PTR_ERR(dentry);
- if (!IS_POSIXACL(nd.dentry->d_inode))
+ if (!IS_POSIXACL(nd.path.dentry->d_inode))
mode &= ~current->fs->umask;
if (!IS_ERR(dentry)) {
switch (mode & S_IFMT) {
case 0: case S_IFREG:
- error = vfs_create(nd.dentry->d_inode,dentry,mode,&nd);
+ error = vfs_create(nd.path.dentry->d_inode,dentry,mode,&nd);
break;
case S_IFCHR: case S_IFBLK:
- error = vfs_mknod(nd.dentry->d_inode,dentry,mode,
+ error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,
new_decode_dev(dev));
break;
case S_IFIFO: case S_IFSOCK:
- error = vfs_mknod(nd.dentry->d_inode,dentry,mode,0);
+ error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,0);
break;
case S_IFDIR:
error = -EPERM;
@@ -1974,7 +1978,7 @@
}
dput(dentry);
}
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_release(&nd);
out:
putname(tmp);
@@ -2029,12 +2033,12 @@
if (IS_ERR(dentry))
goto out_unlock;
- if (!IS_POSIXACL(nd.dentry->d_inode))
+ if (!IS_POSIXACL(nd.path.dentry->d_inode))
mode &= ~current->fs->umask;
- error = vfs_mkdir(nd.dentry->d_inode, dentry, mode);
+ error = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode);
dput(dentry);
out_unlock:
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_release(&nd);
out:
putname(tmp);
@@ -2133,15 +2137,15 @@
error = -EBUSY;
goto exit1;
}
- mutex_lock_nested(&nd.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
if (IS_ERR(dentry))
goto exit2;
- error = vfs_rmdir(nd.dentry->d_inode, dentry);
+ error = vfs_rmdir(nd.path.dentry->d_inode, dentry);
dput(dentry);
exit2:
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
exit1:
path_release(&nd);
exit:
@@ -2209,7 +2213,7 @@
error = -EISDIR;
if (nd.last_type != LAST_NORM)
goto exit1;
- mutex_lock_nested(&nd.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
error = PTR_ERR(dentry);
if (!IS_ERR(dentry)) {
@@ -2219,11 +2223,11 @@
inode = dentry->d_inode;
if (inode)
atomic_inc(&inode->i_count);
- error = vfs_unlink(nd.dentry->d_inode, dentry);
+ error = vfs_unlink(nd.path.dentry->d_inode, dentry);
exit2:
dput(dentry);
}
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
if (inode)
iput(inode); /* truncate the inode here */
exit1:
@@ -2300,10 +2304,10 @@
if (IS_ERR(dentry))
goto out_unlock;
- error = vfs_symlink(nd.dentry->d_inode, dentry, from, S_IALLUGO);
+ error = vfs_symlink(nd.path.dentry->d_inode, dentry, from, S_IALLUGO);
dput(dentry);
out_unlock:
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
path_release(&nd);
out:
putname(to);
@@ -2389,16 +2393,16 @@
if (error)
goto out;
error = -EXDEV;
- if (old_nd.mnt != nd.mnt)
+ if (old_nd.path.mnt != nd.path.mnt)
goto out_release;
new_dentry = lookup_create(&nd, 0);
error = PTR_ERR(new_dentry);
if (IS_ERR(new_dentry))
goto out_unlock;
- error = vfs_link(old_nd.dentry, nd.dentry->d_inode, new_dentry);
+ error = vfs_link(old_nd.path.dentry, nd.path.dentry->d_inode, new_dentry);
dput(new_dentry);
out_unlock:
- mutex_unlock(&nd.dentry->d_inode->i_mutex);
+ mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
out_release:
path_release(&nd);
out:
@@ -2578,15 +2582,15 @@
goto exit1;
error = -EXDEV;
- if (oldnd.mnt != newnd.mnt)
+ if (oldnd.path.mnt != newnd.path.mnt)
goto exit2;
- old_dir = oldnd.dentry;
+ old_dir = oldnd.path.dentry;
error = -EBUSY;
if (oldnd.last_type != LAST_NORM)
goto exit2;
- new_dir = newnd.dentry;
+ new_dir = newnd.path.dentry;
if (newnd.last_type != LAST_NORM)
goto exit2;