f2fs: fix to wait on block writeback for post_read case

If inode is compressed, but not encrypted, it missed to call
f2fs_wait_on_block_writeback() to wait for GCed page writeback
in IPU write path.

Thread A				GC-Thread
					- f2fs_gc
					 - do_garbage_collect
					  - gc_data_segment
					   - move_data_block
					    - f2fs_submit_page_write
					     migrate normal cluster's block via
					     meta_inode's page cache
- f2fs_write_single_data_page
 - f2fs_do_write_data_page
  - f2fs_inplace_write_data
   - f2fs_submit_page_bio

IRQ
- f2fs_read_end_io
					IRQ
					old data overrides new data due to
					out-of-order GC and common IO.
					- f2fs_read_end_io

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 27015b7875aed6da2cb6be2616465802f14ccb43..dce8defdf4c7f910719dc311b5efc7e4ec9fa251 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2556,9 +2556,6 @@ int f2fs_encrypt_one_page(struct f2fs_io_info *fio)
 
        page = fio->compressed_page ? fio->compressed_page : fio->page;
 
-       /* wait for GCed page writeback via META_MAPPING */
-       f2fs_wait_on_block_writeback(inode, fio->old_blkaddr);
-
        if (fscrypt_inode_uses_inline_crypto(inode))
                return 0;
 
@@ -2745,6 +2742,10 @@ got_it:
                goto out_writepage;
        }
 
+       /* wait for GCed page writeback via META_MAPPING */
+       if (fio->post_read)
+               f2fs_wait_on_block_writeback(inode, fio->old_blkaddr);
+
        /*
         * If current allocation needs SSR,
         * it had better in-place writes for updated data.