[PATCH] ext4: Convert timers to use timer_setup()

From: Kees Cook
Date: Wed Oct 04 2017 - 20:53:04 EST


In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: "Theodore Ts'o" <tytso@xxxxxxx>
Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx>
Cc: linux-ext4@xxxxxxxxxxxxxxx
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
This requires commit 686fef928bba ("timer: Prepare to change timer
callback argument type") in v4.14-rc3, but should be otherwise
stand-alone.
---
fs/ext4/super.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index b104096fce9e..1bc7ff8157d8 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2791,14 +2791,11 @@ static int ext4_feature_set_ok(struct super_block *sb, int readonly)
* This function is called once a day if we have errors logged
* on the file system
*/
-static void print_daily_error_info(unsigned long arg)
+static void print_daily_error_info(struct timer_list *t)
{
- struct super_block *sb = (struct super_block *) arg;
- struct ext4_sb_info *sbi;
- struct ext4_super_block *es;
-
- sbi = EXT4_SB(sb);
- es = sbi->s_es;
+ struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
+ struct super_block *sb = sbi->s_sb;
+ struct ext4_super_block *es = sbi->s_es;

if (es->s_error_count)
/* fsck newer than v1.41.13 is needed to clean this condition. */
@@ -3980,8 +3977,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
get_random_bytes(&sbi->s_next_generation, sizeof(u32));
spin_lock_init(&sbi->s_next_gen_lock);

- setup_timer(&sbi->s_err_report, print_daily_error_info,
- (unsigned long) sb);
+ timer_setup(&sbi->s_err_report, print_daily_error_info, 0);

/* Register extent status tree shrinker */
if (ext4_es_register_shrinker(sbi))
--
2.7.4


--
Kees Cook
Pixel Security