Commit 92fc03fb authored by Anand Jain's avatar Anand Jain Committed by David Sterba
Browse files

Btrfs: SB read failure should return EIO for __bread failure 



This will return EIO when __bread() fails to read SB,
instead of EINVAL.

Signed-off-by: default avatarAnand Jain <anand.jain@oracle.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent c1b7e474

fs/btrfs/disk-io.c

+15 −3
Original line number Original line Diff line number Diff line
@@ -2653,8 +2653,8 @@ int open_ctree(struct super_block *sb, 
	 * Read super block and check the signature bytes only

	 * Read super block and check the signature bytes only

	 */

	 */

	bh = btrfs_read_dev_super(fs_devices->latest_bdev);

	bh = btrfs_read_dev_super(fs_devices->latest_bdev);

	if (!bh) {

	if (IS_ERR(bh)) {

		err = -EINVAL;

		err = PTR_ERR(bh);

		goto fail_alloc;

		goto fail_alloc;

	}

	}
@@ -3196,6 +3196,7 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev) 
	int i;

	int i;

	u64 transid = 0;

	u64 transid = 0;

	u64 bytenr;

	u64 bytenr;

	int ret = -EINVAL;





	/* we would like to check all the supers, but that would make

	/* we would like to check all the supers, but that would make

	 * a btrfs mount succeed after a mkfs from a different FS.

	 * a btrfs mount succeed after a mkfs from a different FS.
@@ -3209,13 +3210,20 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev) 
			break;

			break;

		bh = __bread(bdev, bytenr / 4096,

		bh = __bread(bdev, bytenr / 4096,

					BTRFS_SUPER_INFO_SIZE);

					BTRFS_SUPER_INFO_SIZE);

		if (!bh)

		/*

		 * If we fail to read from the underlying devices, as of now

		 * the best option we have is to mark it EIO.

		 */

		if (!bh) {

			ret = -EIO;

			continue;

			continue;

		}





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

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

		if (btrfs_super_bytenr(super) != bytenr ||

		if (btrfs_super_bytenr(super) != bytenr ||

		    btrfs_super_magic(super) != BTRFS_MAGIC) {

		    btrfs_super_magic(super) != BTRFS_MAGIC) {

			brelse(bh);

			brelse(bh);

			ret = -EINVAL;

			continue;

			continue;

		}

		}
@@ -3227,6 +3235,10 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev) 
			brelse(bh);

			brelse(bh);

		}

		}

	}

	}



	if (!latest)

		return ERR_PTR(ret);



	return latest;

	return latest;

}

}

fs/btrfs/volumes.c

+4 −4
Original line number Original line Diff line number Diff line
@@ -211,8 +211,8 @@ btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 
	}

	}

	invalidate_bdev(*bdev);

	invalidate_bdev(*bdev);

	*bh = btrfs_read_dev_super(*bdev);

	*bh = btrfs_read_dev_super(*bdev);

	if (!*bh) {

	if (IS_ERR(*bh)) {

		ret = -EINVAL;

		ret = PTR_ERR(*bh);

		blkdev_put(*bdev, flags);

		blkdev_put(*bdev, flags);

		goto error;

		goto error;

	}

	}
@@ -6746,8 +6746,8 @@ int btrfs_scratch_superblock(struct btrfs_device *device) 
	struct btrfs_super_block *disk_super;

	struct btrfs_super_block *disk_super;





	bh = btrfs_read_dev_super(device->bdev);

	bh = btrfs_read_dev_super(device->bdev);

	if (!bh)

	if (IS_ERR(bh))

		return -EINVAL;

		return PTR_ERR(bh);

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

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





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

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