Commit fd244524 authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
Browse files

f2fs: compress: fix to cover normal cluster write with cp_rwsem 



When we overwrite compressed cluster w/ normal cluster, we should
not unlock cp_rwsem during f2fs_write_raw_pages(), otherwise data
will be corrupted if partial blocks were persisted before CP & SPOR,
due to cluster metadata wasn't updated atomically.

Fixes: 4c8ff709 ("f2fs: support data compression")
Reviewed-by: default avatarDaeho Jeong <daehojeong@google.com>
Signed-off-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 8a430dd4

fs/f2fs/compress.c

+18 −9
Original line number Diff line number Diff line
@@ -1443,12 +1443,14 @@ void f2fs_compress_write_end_io(struct bio *bio, struct page *page) 
}



static int f2fs_write_raw_pages(struct compress_ctx *cc,

					int *submitted,

					int *submitted_p,

					struct writeback_control *wbc,

					enum iostat_type io_type)

{

	struct address_space *mapping = cc->inode->i_mapping;

	int _submitted, compr_blocks, ret, i;

	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);

	int submitted, compr_blocks, i;

	int ret = 0;



	compr_blocks = f2fs_compressed_blocks(cc);
@@ -1463,6 +1465,10 @@ static int f2fs_write_raw_pages(struct compress_ctx *cc, 
	if (compr_blocks < 0)

		return compr_blocks;



	/* overwrite compressed cluster w/ normal cluster */

	if (compr_blocks > 0)

		f2fs_lock_op(sbi);



	for (i = 0; i < cc->cluster_size; i++) {

		if (!cc->rpages[i])

			continue;
@@ -1487,7 +1493,7 @@ static int f2fs_write_raw_pages(struct compress_ctx *cc, 
		if (!clear_page_dirty_for_io(cc->rpages[i]))

			goto continue_unlock;



		ret = f2fs_write_single_data_page(cc->rpages[i], &_submitted,

		ret = f2fs_write_single_data_page(cc->rpages[i], &submitted,

						NULL, NULL, wbc, io_type,

						compr_blocks, false);

		if (ret) {
@@ -1495,26 +1501,29 @@ static int f2fs_write_raw_pages(struct compress_ctx *cc, 
				unlock_page(cc->rpages[i]);

				ret = 0;

			} else if (ret == -EAGAIN) {

				ret = 0;

				/*

				 * for quota file, just redirty left pages to

				 * avoid deadlock caused by cluster update race

				 * from foreground operation.

				 */

				if (IS_NOQUOTA(cc->inode))

					return 0;

				ret = 0;

					goto out;

				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);

				goto retry_write;

			}

			return ret;

			goto out;

		}



		*submitted += _submitted;

		*submitted_p += submitted;

	}



	f2fs_balance_fs(F2FS_M_SB(mapping), true);

out:

	if (compr_blocks > 0)

		f2fs_unlock_op(sbi);



	return 0;

	f2fs_balance_fs(sbi, true);

	return ret;

}



int f2fs_write_multi_pages(struct compress_ctx *cc,

fs/f2fs/data.c

+2 −1
Original line number Diff line number Diff line
@@ -2839,7 +2839,7 @@ int f2fs_write_single_data_page(struct page *page, int *submitted, 
		.encrypted_page = NULL,

		.submitted = 0,

		.compr_blocks = compr_blocks,

		.need_lock = LOCK_RETRY,

		.need_lock = compr_blocks ? LOCK_DONE : LOCK_RETRY,

		.post_read = f2fs_post_read_required(inode) ? 1 : 0,

		.io_type = io_type,

		.io_wbc = wbc,
@@ -2920,6 +2920,7 @@ int f2fs_write_single_data_page(struct page *page, int *submitted, 
	if (err == -EAGAIN) {

		err = f2fs_do_write_data_page(&fio);

		if (err == -EAGAIN) {

			f2fs_bug_on(sbi, compr_blocks);

			fio.need_lock = LOCK_REQ;

			err = f2fs_do_write_data_page(&fio);

		}