Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[sfrench/cifs-2.6.git] / fs / btrfs / super.c
index e99510bfbffd4309edb496fe147f9aba889a2ddc..2ff7cd2db25f4cd0ad85470d1da3c3c676b2646e 100644 (file)
@@ -502,8 +502,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
 
        if (s->s_root) {
                if ((flags ^ s->s_flags) & MS_RDONLY) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        error = -EBUSY;
                        goto error_close_devices;
                }
@@ -517,8 +516,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                error = btrfs_fill_super(s, fs_devices, data,
                                         flags & MS_SILENT ? 1 : 0);
                if (error) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        goto error_free_subvol_name;
                }
 
@@ -535,15 +533,13 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                mutex_unlock(&s->s_root->d_inode->i_mutex);
 
                if (IS_ERR(root)) {
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        error = PTR_ERR(root);
                        goto error_free_subvol_name;
                }
                if (!root->d_inode) {
                        dput(root);
-                       up_write(&s->s_umount);
-                       deactivate_super(s);
+                       deactivate_locked_super(s);
                        error = -ENXIO;
                        goto error_free_subvol_name;
                }
@@ -648,14 +644,9 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
 
-       vol = kmalloc(sizeof(*vol), GFP_KERNEL);
-       if (!vol)
-               return -ENOMEM;
-
-       if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) {
-               ret = -EFAULT;
-               goto out;
-       }
+       vol = memdup_user((void __user *)arg, sizeof(*vol));
+       if (IS_ERR(vol))
+               return PTR_ERR(vol);
 
        switch (cmd) {
        case BTRFS_IOC_SCAN_DEV:
@@ -663,7 +654,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
                                            &btrfs_fs_type, &fs_devices);
                break;
        }
-out:
+
        kfree(vol);
        return ret;
 }