Re: [f2fs-dev] [PATCH v2] f2fs: fix quota_sync failure due to f2fs_lock_op

[Chao Yu]

On 2020/4/17 5:39, Jaegeuk Kim wrote:
> f2fs_quota_sync() uses f2fs_lock_op() before flushing dirty pages, but
> f2fs_write_data_page() returns EAGAIN.
> Likewise dentry blocks, we can just bypass getting the lock, since quota
> blocks are also maintained by checkpoint.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
> v2:
>  - fix multipage write case
> 
>  fs/f2fs/compress.c | 2 +-
>  fs/f2fs/data.c     | 4 ++--
>  2 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index df7b2d15eacde..faaa358289010 100644
> --- a/fs/f2fs/compress.c
> +++ b/fs/f2fs/compress.c
> @@ -985,7 +985,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
>  	loff_t psize;
>  	int i, err;
>  
> -	if (!f2fs_trylock_op(sbi))
> +	if (!IS_NOQUOTA(inode) && !f2fs_trylock_op(sbi))
>  		return -EAGAIN;

I encounter deadlock..

Should call f2fs_unlock_op() for non-quota compressed inode later.

Thanks,

>  
>  	set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index accd28728642a..5c8d3823d7593 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -2656,8 +2656,8 @@ int f2fs_write_single_data_page(struct page *page, int *submitted,
>  			f2fs_available_free_memory(sbi, BASE_CHECK))))
>  		goto redirty_out;
>  
> -	/* Dentry blocks are controlled by checkpoint */
> -	if (S_ISDIR(inode->i_mode)) {
> +	/* Dentry/quota blocks are controlled by checkpoint */
> +	if (S_ISDIR(inode->i_mode) || IS_NOQUOTA(inode)) {
>  		fio.need_lock = LOCK_DONE;
>  		err = f2fs_do_write_data_page(&fio);
>  		goto done;
>