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Commit 42b67427 authored by Anand Jain's avatar Anand Jain Committed by David Sterba
Browse files

btrfs: make use of btrfs_scratch_superblocks() in btrfs_rm_device() 



With the previous patches now the btrfs_scratch_superblocks() is ready to
be used in btrfs_rm_device() so use it.

Signed-off-by: default avatarAnand Jain <anand.jain@oracle.com>
[ use GFP_KERNEL ]
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent b3d1b153

fs/btrfs/volumes.c

+13 −64
Original line number Diff line number Diff line
@@ -1752,13 +1752,11 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) 
{

	struct btrfs_device *device;

	struct btrfs_device *next_device;

	struct block_device *bdev = NULL;

	struct buffer_head *bh = NULL;

	struct btrfs_super_block *disk_super = NULL;

	struct btrfs_fs_devices *cur_devices;

	u64 num_devices;

	int ret = 0;

	bool clear_super = false;

	char *dev_name = NULL;



	mutex_lock(&uuid_mutex);
@@ -1786,6 +1784,11 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) 
		list_del_init(&device->dev_alloc_list);

		device->fs_devices->rw_devices--;

		unlock_chunks(root);

		dev_name = kstrdup(device->name->str, GFP_KERNEL);

		if (!dev_name) {

			ret = -ENOMEM;

			goto error_undo;

		}

		clear_super = true;

	}
@@ -1869,73 +1872,19 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) 
	 * remove it from the devices list and zero out the old super

	 */

	if (clear_super) {

		u64 bytenr;

		int i;



		if (!disk_super) {

			ret = btrfs_get_bdev_and_sb(device_path,

					FMODE_WRITE | FMODE_EXCL,

					root->fs_info->bdev_holder, 0,

					&bdev, &bh);

			if (ret) {

				/*

				 * It could be a failed device ok for clear_super

				 * to fail. So return success

				 */

				ret = 0;

				goto out;

			}



			disk_super = (struct btrfs_super_block *)bh->b_data;

		}

		/* make sure this device isn't detected as part of

		 * the FS anymore

		 */

		memset(&disk_super->magic, 0, sizeof(disk_super->magic));

		set_buffer_dirty(bh);

		sync_dirty_buffer(bh);

		brelse(bh);



		/* clear the mirror copies of super block on the disk

		 * being removed, 0th copy is been taken care above and

		 * the below would take of the rest

		 */

		for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {

			bytenr = btrfs_sb_offset(i);

			if (bytenr + BTRFS_SUPER_INFO_SIZE >=

					i_size_read(bdev->bd_inode))

				break;



			bh = __bread(bdev, bytenr / 4096,

					BTRFS_SUPER_INFO_SIZE);

			if (!bh)

				continue;



			disk_super = (struct btrfs_super_block *)bh->b_data;



			if (btrfs_super_bytenr(disk_super) != bytenr ||

				btrfs_super_magic(disk_super) != BTRFS_MAGIC) {

				brelse(bh);

				continue;

			}

			memset(&disk_super->magic, 0,

						sizeof(disk_super->magic));

			set_buffer_dirty(bh);

			sync_dirty_buffer(bh);

			brelse(bh);

		}



		if (bdev) {

			/* Notify udev that device has changed */

			btrfs_kobject_uevent(bdev, KOBJ_CHANGE);

		struct block_device *bdev;



			/* Update ctime/mtime for device path for libblkid */

			update_dev_time(device_path);

		bdev = blkdev_get_by_path(dev_name, FMODE_READ | FMODE_EXCL,

						root->fs_info->bdev_holder);

		if (!IS_ERR(bdev)) {

			btrfs_scratch_superblocks(bdev, dev_name);

			blkdev_put(bdev, FMODE_READ | FMODE_EXCL);

		}

	}



out:

	kfree(dev_name);



	mutex_unlock(&uuid_mutex);

	return ret;