Commit 6fd257cb authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
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f2fs: fix to keep consistent i_gc_rwsem lock order 



i_gc_rwsem[WRITE] and i_gc_rwsem[READ] lock order is reversed
in gc_data_segment() and f2fs_dio_write_iter(), fix to keep
consistent lock order as below:
1. lock i_gc_rwsem[WRITE]
2. lock i_gc_rwsem[READ]

Signed-off-by: default avatarChao Yu <chao@kernel.org>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent c9b3649a

fs/f2fs/gc.c

+4 −4
Original line number Diff line number Diff line
@@ -1616,14 +1616,14 @@ static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, 
			int err;



			if (S_ISREG(inode->i_mode)) {

				if (!f2fs_down_write_trylock(&fi->i_gc_rwsem[READ])) {

				if (!f2fs_down_write_trylock(&fi->i_gc_rwsem[WRITE])) {

					sbi->skipped_gc_rwsem++;

					continue;

				}

				if (!f2fs_down_write_trylock(

						&fi->i_gc_rwsem[WRITE])) {

						&fi->i_gc_rwsem[READ])) {

					sbi->skipped_gc_rwsem++;

					f2fs_up_write(&fi->i_gc_rwsem[READ]);

					f2fs_up_write(&fi->i_gc_rwsem[WRITE]);

					continue;

				}

				locked = true;
@@ -1646,8 +1646,8 @@ static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, 
				submitted++;



			if (locked) {

				f2fs_up_write(&fi->i_gc_rwsem[WRITE]);

				f2fs_up_write(&fi->i_gc_rwsem[READ]);

				f2fs_up_write(&fi->i_gc_rwsem[WRITE]);

			}



			stat_inc_data_blk_count(sbi, 1, gc_type);