[PATCH] btrfs: zoned: fix zone number to sector/physical calculation
From: Naohiro Aota <naohiro.aota@wdc.com>
Date: 2021-05-27 01:47:35
Also in:
linux-btrfs
Subsystem:
btrfs file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Chris Mason, David Sterba, Alexander Viro, Christian Brauner, Linus Torvalds
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.
Fixes: 12659251ca5d ("btrfs: implement log-structured superblock for ZONED mode")
Cc: stable@vger.kernel.org # 5.11+
Reported-by: Dmitry Fomichev <redacted>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
fs/btrfs/zoned.c | 23 ++++++++++++++++++-----
1 file changed, 18 insertions(+), 5 deletions(-)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 5feb76bdfc06..a7f77f0a5a86 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c@@ -153,6 +153,19 @@ 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) +{ + sector_t zone_sectors = bdev_zone_sectors(bdev); + + return (sector_t)zone_number << ilog2(zone_sectors); +} + +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
@@ -408,8 +421,7 @@ 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)
@@ -736,7 +748,7 @@ 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)
@@ -841,7 +853,7 @@ 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); }
@@ -893,7 +905,8 @@ 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; }
--
2.31.1