[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem

[pandora-kernel.git] / fs / namespace.c

diff --git a/fs/namespace.c b/fs/namespace.c
index 2019899..f0e353f 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -451,7 +451,7 @@ EXPORT_SYMBOL(may_umount);
 void release_mounts(struct list_head *head)
 {
        struct vfsmount *mnt;
-       while(!list_empty(head)) {
+       while (!list_empty(head)) {
                mnt = list_entry(head->next, struct vfsmount, mnt_hash);
                list_del_init(&mnt->mnt_hash);
                if (mnt->mnt_parent != mnt) {
@@ -814,7 +814,7 @@ static int graft_tree(struct vfsmount *mnt, struct nameidata *nd)
                return -ENOTDIR;
 
        err = -ENOENT;
-       down(&nd->dentry->d_inode->i_sem);
+       mutex_lock(&nd->dentry->d_inode->i_mutex);
        if (IS_DEADDIR(nd->dentry->d_inode))
                goto out_unlock;
 
@@ -826,7 +826,7 @@ static int graft_tree(struct vfsmount *mnt, struct nameidata *nd)
        if (IS_ROOT(nd->dentry) || !d_unhashed(nd->dentry))
                err = attach_recursive_mnt(mnt, nd, NULL);
 out_unlock:
-       up(&nd->dentry->d_inode->i_sem);
+       mutex_unlock(&nd->dentry->d_inode->i_mutex);
        if (!err)
                security_sb_post_addmount(mnt, nd);
        return err;
@@ -962,7 +962,7 @@ static int do_move_mount(struct nameidata *nd, char *old_name)
                goto out;
 
        err = -ENOENT;
-       down(&nd->dentry->d_inode->i_sem);
+       mutex_lock(&nd->dentry->d_inode->i_mutex);
        if (IS_DEADDIR(nd->dentry->d_inode))
                goto out1;
 
@@ -1004,7 +1004,7 @@ static int do_move_mount(struct nameidata *nd, char *old_name)
        list_del_init(&old_nd.mnt->mnt_expire);
        spin_unlock(&vfsmount_lock);
 out1:
-       up(&nd->dentry->d_inode->i_sem);
+       mutex_unlock(&nd->dentry->d_inode->i_mutex);
 out:
        up_write(&namespace_sem);
        if (!err)
@@ -1526,6 +1526,10 @@ static void chroot_fs_refs(struct nameidata *old_nd, struct nameidata *new_nd)
  * pointed to by put_old must yield the same directory as new_root. No other
  * file system may be mounted on put_old. After all, new_root is a mountpoint.
  *
+ * Also, the current root cannot be on the 'rootfs' (initial ramfs) filesystem.
+ * See Documentation/filesystems/ramfs-rootfs-initramfs.txt for alternatives
+ * in this situation.
+ *
  * Notes:
  *  - we don't move root/cwd if they are not at the root (reason: if something
  *    cared enough to change them, it's probably wrong to force them elsewhere)
@@ -1569,7 +1573,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root,
        user_nd.dentry = dget(current->fs->root);
        read_unlock(&current->fs->lock);
        down_write(&namespace_sem);
-       down(&old_nd.dentry->d_inode->i_sem);
+       mutex_lock(&old_nd.dentry->d_inode->i_mutex);
        error = -EINVAL;
        if (IS_MNT_SHARED(old_nd.mnt) ||
                IS_MNT_SHARED(new_nd.mnt->mnt_parent) ||
@@ -1622,7 +1626,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root,
        path_release(&root_parent);
        path_release(&parent_nd);
 out2:
-       up(&old_nd.dentry->d_inode->i_sem);
+       mutex_unlock(&old_nd.dentry->d_inode->i_mutex);
        up_write(&namespace_sem);
        path_release(&user_nd);
        path_release(&old_nd);