Commit 3613249a authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
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btrfs: warn about dev extents that are inside the reserved range 



Btrfs on-disk format has reserved the first 1MiB for the primary super
block (at 64KiB offset) and bootloaders may also use this space.

This behavior is only introduced since v4.1 btrfs-progs release,
although kernel can ensure we never touch the reserved range of super
blocks, it's better to inform the end users, and a balance will resolve
the problem.

Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
[ update changelog and message ]
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 37f85ec3

fs/btrfs/volumes.c

+10 −0
Original line number Diff line number Diff line
@@ -7996,6 +7996,16 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info, 
		goto out;

	}



	/*

	 * Very old mkfs.btrfs (before v4.1) will not respect the reserved

	 * space. Although kernel can handle it without problem, better to warn

	 * the users.

	 */

	if (physical_offset < BTRFS_DEVICE_RANGE_RESERVED)

		btrfs_warn(fs_info,

		"devid %llu physical %llu len %llu inside the reserved space",

			   devid, physical_offset, physical_len);



	for (i = 0; i < map->num_stripes; i++) {

		if (map->stripes[i].dev->devid == devid &&

		    map->stripes[i].physical == physical_offset) {