Hi Jaegeuk,
I think we need this patch in order to avoid writebacking incomplete data
compressed by zstd.
On 2020/5/8 9:16, Chao Yu wrote:
> During zstd compression, ZSTD_endStream() may return non-zero value
> because distination buffer is full, but there is still compressed data
> remained in intermediate buffer, it means that zstd algorithm can not
> save at last one block space, let's just writeback raw data instead of
> compressed one, this can fix data corruption when decompressing
> incomplete stored compression data.
>
Fixes: 50cfa66f0de0 ("f2fs: compress: support zstd compress algorithm")
Thanks,
> Signed-off-by: Daeho Jeong <daehoje...@google.com>
> Signed-off-by: Chao Yu <yuch...@huawei.com>
> ---
> fs/f2fs/compress.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index c22cc0d37369..5e4947250262 100644
> --- a/fs/f2fs/compress.c
> +++ b/fs/f2fs/compress.c
> @@ -358,6 +358,13 @@ static int zstd_compress_pages(struct compress_ctx *cc)
> return -EIO;
> }
>
> + /*
> + * there is compressed data remained in intermediate buffer due to
> + * no more space in cbuf.cdata
> + */
> + if (ret)
> + return -EAGAIN;
> +
> cc->clen = outbuf.pos;
> return 0;
> }
>
