btrfs: move volume_mutex to callers of btrfs_rm_device

Move locking and unlocking next to the BTRFS_FS_EXCL_OP bit manipulation
so it's obvious that the two happen at the same time.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 7beec1b..937afa8 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2480,6 +2480,7 @@ static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
                ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
                goto out;
        }
+       mutex_lock(&fs_info->volume_mutex);
 
        if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
                ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
@@ -2487,6 +2488,7 @@ static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
                vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
                ret = btrfs_rm_device(fs_info, vol_args->name, 0);
        }
+       mutex_unlock(&fs_info->volume_mutex);
        clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 
        if (!ret) {
@@ -2522,6 +2524,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
                ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
                goto out_drop_write;
        }
+       mutex_lock(&fs_info->volume_mutex);
 
        vol_args = memdup_user(arg, sizeof(*vol_args));
        if (IS_ERR(vol_args)) {
@@ -2536,6 +2539,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
                btrfs_info(fs_info, "disk deleted %s", vol_args->name);
        kfree(vol_args);
 out:
+       mutex_unlock(&fs_info->volume_mutex);
        clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 out_drop_write:
        mnt_drop_write_file(file);

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 488935e..1da4636 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1954,7 +1954,6 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path,
        u64 num_devices;
        int ret = 0;
 
-       mutex_lock(&fs_info->volume_mutex);
        mutex_lock(&uuid_mutex);
 
        num_devices = fs_devices->num_devices;
@@ -2068,7 +2067,6 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path,
 
 out:
        mutex_unlock(&uuid_mutex);
-       mutex_unlock(&fs_info->volume_mutex);
        return ret;
 
 error_undo: