From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp2130.oracle.com ([141.146.126.79]:48914 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751021AbdLHH4m (ORCPT ); Fri, 8 Dec 2017 02:56:42 -0500 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.21/8.16.0.21) with SMTP id vB87ufYn018128 for ; Fri, 8 Dec 2017 07:56:41 GMT Received: from aserv0022.oracle.com (aserv0022.oracle.com [141.146.126.234]) by aserp2130.oracle.com with ESMTP id 2eqp6e04ca-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 08 Dec 2017 07:56:41 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by aserv0022.oracle.com (8.14.4/8.14.4) with ESMTP id vB87ueHU009006 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Fri, 8 Dec 2017 07:56:40 GMT Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id vB87ueQr022499 for ; Fri, 8 Dec 2017 07:56:40 GMT From: Anand Jain To: linux-btrfs@vger.kernel.org Subject: [PATCH RFC] btrfs: self heal from SB fail Date: Fri, 8 Dec 2017 15:57:05 +0800 Message-Id: <20171208075705.23462-1-anand.jain@oracle.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: -EXPERIMENTAL- As of now when primary SB fails we won't self heal and would fail mount, this is an experimental patch which thinks why not go and read backup copy. Signed-off-by: Anand Jain --- fs/btrfs/disk-io.c | 8 +++++++- fs/btrfs/volumes.c | 10 +++++++--- 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 9b20c1f3563b..a791b8dfe8a8 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3190,7 +3190,7 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev) * So, we need to add a special mount option to scan for * later supers, using BTRFS_SUPER_MIRROR_MAX instead */ - for (i = 0; i < 1; i++) { + for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { ret = btrfs_read_dev_one_super(bdev, i, &bh); if (ret) continue; @@ -4015,11 +4015,17 @@ static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info) ret = -EINVAL; } +#if 0 + /* + * Need a way to check for any copy of SB, as its not a + * strong check, just ignore this for now. + */ if (btrfs_super_bytenr(sb) != BTRFS_SUPER_INFO_OFFSET) { btrfs_err(fs_info, "super offset mismatch %llu != %u", btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET); ret = -EINVAL; } +#endif /* * Obvious sys_chunk_array corruptions, it must hold at least one key diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 9fa2539a8493..f368db94d62b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1369,7 +1369,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, { struct btrfs_super_block *disk_super; struct block_device *bdev; - struct page *page; + struct buffer_head *sb_bh; int ret = -EINVAL; u64 devid; u64 transid; @@ -1392,8 +1392,12 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, goto error; } - if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) + sb_bh = btrfs_read_dev_super(bdev); + if (IS_ERR(sb_bh)) { + ret = PTR_ERR(sb_bh); goto error_bdev_put; + } + disk_super = (struct btrfs_super_block *) sb_bh->b_data; devid = btrfs_stack_device_id(&disk_super->dev_item); transid = btrfs_super_generation(disk_super); @@ -1413,7 +1417,7 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, if (!ret && fs_devices_ret) (*fs_devices_ret)->total_devices = total_devices; - btrfs_release_disk_super(page); + brelse(sb_bh); error_bdev_put: blkdev_put(bdev, flags); -- 2.7.0