From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sahitya Tummala Subject: [PATCH] f2fs: fix data corruption issue with hardware encryption Date: Wed, 10 Oct 2018 10:56:22 +0530 Message-ID: <1539149182-12729-1-git-send-email-stummala@codeaurora.org> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Jaegeuk Kim , Chao Yu , linux-f2fs-devel@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, Sahitya Tummala List-Id: linux-f2fs-devel.lists.sourceforge.net Direct IO can be used in case of hardware encryption. The following scenario results into data corruption issue in this path - Thread A - Thread B- -> write file#1 in direct IO -> GC gets kicked in -> GC submitted bio on meta mapping for file#1, but pending completion -> write file#1 again with new data in direct IO -> GC bio gets completed now -> GC writes old data to the new location and thus file#1 is corrupted. Fix this by submitting and waiting for pending io on meta mapping for direct IO case in f2fs_map_blocks(). Signed-off-by: Sahitya Tummala --- fs/f2fs/data.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 9ef6f1f..7b2fef0 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1028,6 +1028,12 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, map->m_pblk = ei.blk + pgofs - ei.fofs; map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs); map->m_flags = F2FS_MAP_MAPPED; + /* for HW encryption, but to avoid potential issue in future */ + if (flag == F2FS_GET_BLOCK_DIO) { + blkaddr = map->m_pblk; + for (; blkaddr < map->m_pblk + map->m_len; blkaddr++) + f2fs_wait_on_block_writeback(sbi, blkaddr); + } if (map->m_next_extent) *map->m_next_extent = pgofs + map->m_len; goto out; @@ -1188,6 +1194,12 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, goto next_dnode; sync_out: + /* for hardware encryption, but to avoid potential issue in future */ + if (flag == F2FS_GET_BLOCK_DIO && map->m_flags & F2FS_MAP_MAPPED) { + blkaddr = map->m_pblk; + for (; blkaddr < map->m_pblk + map->m_len; blkaddr++) + f2fs_wait_on_block_writeback(sbi, blkaddr); + } if (flag == F2FS_GET_BLOCK_PRECACHE) { if (map->m_flags & F2FS_MAP_MAPPED) { unsigned int ofs = start_pgofs - map->m_lblk; -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.