[Devel] [PATCH vz9 4/5] fs: sync: introduce argument struct for helper routines

[Kirill Tkhai]

On 22.11.2021 09:20, Nikita Yushchenko wrote:
> In this commit, this replaces passing an integer flag by pointer.
> 
> With implementation of per-VE sync, this will be also used to pass
> VE where sync happens.
> 
> https://jira.sw.ru/browse/PSBM-44684
> Signed-off-by: Nikita Yushchenko <nikita.yushchenko at virtuozzo.com>

Reviewed-by: Kirill Tkhai <ktkhai at virtuozzo.com>

> ---
>  fs/sync.c | 28 +++++++++++++++++++---------
>  1 file changed, 19 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/sync.c b/fs/sync.c
> index f57e22fb118f..31e6f0c6402d 100644
> --- a/fs/sync.c
> +++ b/fs/sync.c
> @@ -69,6 +69,10 @@ int sync_filesystem(struct super_block *sb)
>  }
>  EXPORT_SYMBOL(sync_filesystem);
>  
> +struct sync_arg {
> +	int wait;
> +};
> +
>  static void sync_inodes_one_sb(struct super_block *sb, void *arg)
>  {
>  	if (!sb_rdonly(sb))
> @@ -77,9 +81,11 @@ static void sync_inodes_one_sb(struct super_block *sb, void *arg)
>  
>  static void sync_fs_one_sb(struct super_block *sb, void *arg)
>  {
> +	struct sync_arg *sarg = arg;
> +
>  	if (!sb_rdonly(sb) && !(sb->s_iflags & SB_I_SKIP_SYNC) &&
>  	    sb->s_op->sync_fs)
> -		sb->s_op->sync_fs(sb, *(int *)arg);
> +		sb->s_op->sync_fs(sb, sarg->wait);
>  }
>  
>  static void fdatawrite_one_bdev(struct block_device *bdev, void *arg)
> @@ -120,15 +126,17 @@ int ve_fsync_behavior(void)
>   */
>  void ksys_sync(void)
>  {
> -	int nowait = 0, wait = 1;
> +	struct sync_arg sarg;
>  
>  	if (ve_fsync_behavior() == FSYNC_NEVER)
>  		return;
>  
>  	wakeup_flusher_threads(WB_REASON_SYNC);
>  	iterate_supers(sync_inodes_one_sb, NULL);
> -	iterate_supers(sync_fs_one_sb, &nowait);
> -	iterate_supers(sync_fs_one_sb, &wait);
> +	sarg.wait = 0;
> +	iterate_supers(sync_fs_one_sb, &sarg);
> +	sarg.wait = 1;
> +	iterate_supers(sync_fs_one_sb, &sarg);
>  	iterate_bdevs(fdatawrite_one_bdev, NULL);
>  	iterate_bdevs(fdatawait_one_bdev, NULL);
>  	if (unlikely(laptop_mode))
> @@ -143,17 +151,19 @@ SYSCALL_DEFINE0(sync)
>  
>  static void do_sync_work(struct work_struct *work)
>  {
> -	int nowait = 0;
> +	struct sync_arg sarg;
> +
> +	sarg.wait = 0;
>  
>  	/*
>  	 * Sync twice to reduce the possibility we skipped some inodes / pages
>  	 * because they were temporarily locked
>  	 */
> -	iterate_supers(sync_inodes_one_sb, &nowait);
> -	iterate_supers(sync_fs_one_sb, &nowait);
> +	iterate_supers(sync_inodes_one_sb, &sarg);
> +	iterate_supers(sync_fs_one_sb, &sarg);
>  	iterate_bdevs(fdatawrite_one_bdev, NULL);
> -	iterate_supers(sync_inodes_one_sb, &nowait);
> -	iterate_supers(sync_fs_one_sb, &nowait);
> +	iterate_supers(sync_inodes_one_sb, &sarg);
> +	iterate_supers(sync_fs_one_sb, &sarg);
>  	iterate_bdevs(fdatawrite_one_bdev, NULL);
>  	printk("Emergency Sync complete\n");
>  	kfree(work);
>