Commit 5b434df8 authored by Naohiro Aota's avatar Naohiro Aota Committed by David Sterba
Browse files

btrfs: zoned: fix zone number to sector/physical calculation 



In btrfs_get_dev_zone_info(), we have "u32 sb_zone" and calculate "sector_t
sector" by shifting it. But, this "sector" is calculated in 32bit, leading
it to be 0 for the 2nd superblock copy.

Since zone number is u32, shifting it to sector (sector_t) or physical
address (u64) can easily trigger a missing cast bug like this.

This commit introduces helpers to convert zone number to sector/LBA, so we
won't fall into the same pitfall again.

Reported-by: default avatarDmitry Fomichev <Dmitry.Fomichev@wdc.com>
Fixes: 12659251 ("btrfs: implement log-structured superblock for ZONED mode")
CC: stable@vger.kernel.org # 5.11+
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarNaohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 165ea85f

fs/btrfs/zoned.c

+18 −5
Original line number Diff line number Diff line
@@ -150,6 +150,18 @@ static inline u32 sb_zone_number(int shift, int mirror) 
	return (u32)zone;

}



static inline sector_t zone_start_sector(u32 zone_number,

					 struct block_device *bdev)

{

	return (sector_t)zone_number << ilog2(bdev_zone_sectors(bdev));

}



static inline u64 zone_start_physical(u32 zone_number,

				      struct btrfs_zoned_device_info *zone_info)

{

	return (u64)zone_number << zone_info->zone_size_shift;

}



/*

 * Emulate blkdev_report_zones() for a non-zoned device. It slices up the block

 * device into static sized chunks and fake a conventional zone on each of
@@ -405,8 +417,8 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device) 
		if (sb_zone + 1 >= zone_info->nr_zones)

			continue;



		sector = sb_zone << (zone_info->zone_size_shift - SECTOR_SHIFT);

		ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT,

		ret = btrfs_get_dev_zones(device,

					  zone_start_physical(sb_zone, zone_info),

					  &zone_info->sb_zones[sb_pos],

					  &nr_zones);

		if (ret)
@@ -721,7 +733,7 @@ int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw, 
	if (sb_zone + 1 >= nr_zones)

		return -ENOENT;



	ret = blkdev_report_zones(bdev, sb_zone << zone_sectors_shift,

	ret = blkdev_report_zones(bdev, zone_start_sector(sb_zone, bdev),

				  BTRFS_NR_SB_LOG_ZONES, copy_zone_info_cb,

				  zones);

	if (ret < 0)
@@ -826,7 +838,7 @@ int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror) 
		return -ENOENT;



	return blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,

				sb_zone << zone_sectors_shift,

				zone_start_sector(sb_zone, bdev),

				zone_sectors * BTRFS_NR_SB_LOG_ZONES, GFP_NOFS);

}
@@ -878,7 +890,8 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start, 
			if (!(end <= sb_zone ||

			      sb_zone + BTRFS_NR_SB_LOG_ZONES <= begin)) {

				have_sb = true;

				pos = ((u64)sb_zone + BTRFS_NR_SB_LOG_ZONES) << shift;

				pos = zone_start_physical(

					sb_zone + BTRFS_NR_SB_LOG_ZONES, zinfo);

				break;

			}