| From 9d5c4f5c7a2c7677e1b3942772122b032c265aae Mon Sep 17 00:00:00 2001 |
| From: Jaegeuk Kim <jaegeuk@kernel.org> |
| Date: Tue, 7 Oct 2025 03:32:30 +0000 |
| Subject: f2fs: fix wrong block mapping for multi-devices |
| |
| From: Jaegeuk Kim <jaegeuk@kernel.org> |
| |
| commit 9d5c4f5c7a2c7677e1b3942772122b032c265aae upstream. |
| |
| Assuming the disk layout as below, |
| |
| disk0: 0 --- 0x00035abfff |
| disk1: 0x00035ac000 --- 0x00037abfff |
| disk2: 0x00037ac000 --- 0x00037ebfff |
| |
| and we want to read data from offset=13568 having len=128 across the block |
| devices, we can illustrate the block addresses like below. |
| |
| 0 .. 0x00037ac000 ------------------- 0x00037ebfff, 0x00037ec000 ------- |
| | ^ ^ ^ |
| | fofs 0 13568 13568+128 |
| | ------------------------------------------------------ |
| | LBA 0x37e8aa9 0x37ebfa9 0x37ec029 |
| --- map 0x3caa9 0x3ffa9 |
| |
| In this example, we should give the relative map of the target block device |
| ranging from 0x3caa9 to 0x3ffa9 where the length should be calculated by |
| 0x37ebfff + 1 - 0x37ebfa9. |
| |
| In the below equation, however, map->m_pblk was supposed to be the original |
| address instead of the one from the target block address. |
| |
| - map->m_len = min(map->m_len, dev->end_blk + 1 - map->m_pblk); |
| |
| Cc: stable@vger.kernel.org |
| Fixes: 71f2c8206202 ("f2fs: multidevice: support direct IO") |
| Reviewed-by: Chao Yu <chao@kernel.org> |
| Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| fs/f2fs/data.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/fs/f2fs/data.c |
| +++ b/fs/f2fs/data.c |
| @@ -1508,8 +1508,8 @@ static bool f2fs_map_blocks_cached(struc |
| struct f2fs_dev_info *dev = &sbi->devs[bidx]; |
| |
| map->m_bdev = dev->bdev; |
| - map->m_pblk -= dev->start_blk; |
| map->m_len = min(map->m_len, dev->end_blk + 1 - map->m_pblk); |
| + map->m_pblk -= dev->start_blk; |
| } else { |
| map->m_bdev = inode->i_sb->s_bdev; |
| } |
