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

From: Jaegeuk Kim
Date: Thu Apr 23 2020 - 23:35:30 EST


On 04/24, Chao Yu wrote:
> On 2020/4/24 3:49, Jaegeuk Kim wrote:
> > On 04/23, Chao Yu wrote:
> >> 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.
> >
> > Could you elaborate a bit?
>
> I meant we need to change as below, otherwise, cp_rwsem can be negative
> after f2fs_unlock_op if writebacked datas are belong to compressed quota
> file.

Ah, I see. Fixed.

Thanks,

>
> >From 817dc629c47d3000c595640ecb3099b880519d47 Mon Sep 17 00:00:00 2001
> From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> Date: Thu, 9 Apr 2020 10:25:21 -0700
> Subject: [PATCH] f2fs: fix quota_sync failure due to f2fs_lock_op
>
> 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.
>
> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
> fs/f2fs/compress.c | 8 +++++---
> fs/f2fs/data.c | 4 ++--
> 2 files changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index df7b2d15eacd..26b071afe48a 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;
>
> set_new_dnode(&dn, cc->inode, NULL, NULL, 0);
> @@ -1092,7 +1092,8 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
> set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
>
> f2fs_put_dnode(&dn);
> - f2fs_unlock_op(sbi);
> + if (!IS_NOQUOTA(inode))
> + f2fs_unlock_op(sbi);
>
> spin_lock(&fi->i_size_lock);
> if (fi->last_disk_size < psize)
> @@ -1118,7 +1119,8 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
> out_put_dnode:
> f2fs_put_dnode(&dn);
> out_unlock_op:
> - f2fs_unlock_op(sbi);
> + if (!IS_NOQUOTA(inode))
> + f2fs_unlock_op(sbi);
> return -EAGAIN;
> }
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 8dd48c5b6c0d..dd439dbb134d 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -2660,8 +2660,8 @@ 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;
> --
> 2.18.0.rc1
>
>
>
> >
> >>
> >> 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;
> >>>
> > .
> >