From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yang Shi Subject: [PATCH] f2fs: mutex can't be used by down_write_nest_lock() Date: Fri, 26 Feb 2016 16:25:25 -0800 Message-ID: <1456532725-4126-1-git-send-email-yang.shi@linaro.org> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: jaegeuk@kernel.org, cm224.lee@samsung.com, chao2.yu@samsung.com, tglx@linutronix.de, rostedt@goodmis.org, bigeasy@linutronix.de Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-rt-users@vger.kernel.org, linaro-kernel@lists.linaro.org, yang.shi@linaro.org List-Id: linux-f2fs-devel.lists.sourceforge.net fsf2_lock_all() calls down_write_nest_lock() to acquire a rw_sem and check a mutex, but down_write_nest_lock() is designed for two rw_sem accoring to the comment in include/linux/rwsem.h. And, other than f2fs, it is just called in mm/mmap.c with two rwsem. So, it looks it is used wrongly by f2fs. And, it causes the below compile warning on -rt kernel too. In file included from fs/f2fs/xattr.c:25:0: fs/f2fs/f2fs.h: In function 'f2fs_lock_all': fs/f2fs/f2fs.h:962:34: warning: passing argument 2 of 'down_write_nest_lock' from incompatible pointer type [-Wincompatible-pointer-types] f2fs_down_write(&sbi->cp_rwsem, &sbi->cp_mutex); ^ fs/f2fs/f2fs.h:27:55: note: in definition of macro 'f2fs_down_write' #define f2fs_down_write(x, y) down_write_nest_lock(x, y) ^ In file included from include/linux/rwsem.h:22:0, from fs/f2fs/xattr.c:21: include/linux/rwsem_rt.h:138:20: note: expected 'struct rw_semaphore *' but argument is of type 'struct mutex *' static inline void down_write_nest_lock(struct rw_semaphore *sem, Signed-off-by: Yang Shi --- fs/f2fs/f2fs.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index ff79054..af77c1a 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -25,7 +25,6 @@ #ifdef CONFIG_F2FS_CHECK_FS #define f2fs_bug_on(sbi, condition) BUG_ON(condition) -#define f2fs_down_write(x, y) down_write_nest_lock(x, y) #else #define f2fs_bug_on(sbi, condition) \ do { \ @@ -34,7 +33,6 @@ set_sbi_flag(sbi, SBI_NEED_FSCK); \ } \ } while (0) -#define f2fs_down_write(x, y) down_write(x) #endif /* @@ -1006,7 +1004,7 @@ static inline void f2fs_unlock_op(struct f2fs_sb_info *sbi) static inline void f2fs_lock_all(struct f2fs_sb_info *sbi) { - f2fs_down_write(&sbi->cp_rwsem, &sbi->cp_mutex); + down_write(&sbi->cp_rwsem); } static inline void f2fs_unlock_all(struct f2fs_sb_info *sbi) -- 2.0.2