f2fs: fix data corruption issue with hardware encryption

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 <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 8a831f1..00b37a1 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1053,6 +1053,11 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
                map->m_flags = F2FS_MAP_MAPPED;
                if (map->m_next_extent)
                        *map->m_next_extent = pgofs + map->m_len;
+
+               /* for hardware encryption, but to avoid potential issue in future */
+               if (flag == F2FS_GET_BLOCK_DIO)
+                       f2fs_wait_on_block_writeback_range(inode,
+                                               map->m_pblk, map->m_len);
                goto out;
        }
 
@@ -1211,6 +1216,12 @@ skip:
        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)
+               f2fs_wait_on_block_writeback_range(inode,
+                                               map->m_pblk, map->m_len);
+
        if (flag == F2FS_GET_BLOCK_PRECACHE) {
                if (map->m_flags & F2FS_MAP_MAPPED) {
                        unsigned int ofs = start_pgofs - map->m_lblk;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index c25c678..5c80eca 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2988,6 +2988,8 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
 void f2fs_wait_on_page_writeback(struct page *page,
                        enum page_type type, bool ordered);
 void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr);
+void f2fs_wait_on_block_writeback_range(struct inode *inode, block_t blkaddr,
+                                                               block_t len);
 void f2fs_write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
 void f2fs_write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk);
 int f2fs_lookup_journal_in_cursum(struct f2fs_journal *journal, int type,

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e38b2f6..6edcf83 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3303,6 +3303,15 @@ void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr)
        }
 }
 
+void f2fs_wait_on_block_writeback_range(struct inode *inode, block_t blkaddr,
+                                                               block_t len)
+{
+       block_t i;
+
+       for (i = 0; i < len; i++)
+               f2fs_wait_on_block_writeback(inode, blkaddr + i);
+}
+
 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
 {
        struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);