Re: [PATCH 1/3] mm: zswap: use sg_set_folio() in zswap_{compress/decompress}()

[Chengming Zhou]

On 2024/5/24 11:38, Yosry Ahmed wrote:
> sg_set_folio() is equivalent to sg_set_page() for order-0 folios, which
> are the only ones supported by zswap. Now zswap_decompress() can take in
> a folio directly.
> 
> Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>

LGTM, thanks!

Reviewed-by: Chengming Zhou <chengming.zhou@xxxxxxxxx>

> ---
>  mm/zswap.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/mm/zswap.c b/mm/zswap.c
> index a50e2986cd2fa..3693df96c81fe 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -917,7 +917,7 @@ static bool zswap_compress(struct folio *folio, struct zswap_entry *entry)
>  
>  	dst = acomp_ctx->buffer;
>  	sg_init_table(&input, 1);
> -	sg_set_page(&input, &folio->page, PAGE_SIZE, 0);
> +	sg_set_folio(&input, folio, PAGE_SIZE, 0);
>  
>  	/*
>  	 * We need PAGE_SIZE * 2 here since there maybe over-compression case,
> @@ -971,7 +971,7 @@ static bool zswap_compress(struct folio *folio, struct zswap_entry *entry)
>  	return comp_ret == 0 && alloc_ret == 0;
>  }
>  
> -static void zswap_decompress(struct zswap_entry *entry, struct page *page)
> +static void zswap_decompress(struct zswap_entry *entry, struct folio *folio)
>  {
>  	struct zpool *zpool = zswap_find_zpool(entry);
>  	struct scatterlist input, output;
> @@ -1000,7 +1000,7 @@ static void zswap_decompress(struct zswap_entry *entry, struct page *page)
>  
>  	sg_init_one(&input, src, entry->length);
>  	sg_init_table(&output, 1);
> -	sg_set_page(&output, page, PAGE_SIZE, 0);
> +	sg_set_folio(&output, folio, PAGE_SIZE, 0);
>  	acomp_request_set_params(acomp_ctx->req, &input, &output, entry->length, PAGE_SIZE);
>  	BUG_ON(crypto_wait_req(crypto_acomp_decompress(acomp_ctx->req), &acomp_ctx->wait));
>  	BUG_ON(acomp_ctx->req->dlen != PAGE_SIZE);
> @@ -1073,7 +1073,7 @@ static int zswap_writeback_entry(struct zswap_entry *entry,
>  		return -ENOMEM;
>  	}
>  
> -	zswap_decompress(entry, &folio->page);
> +	zswap_decompress(entry, folio);
>  
>  	count_vm_event(ZSWPWB);
>  	if (entry->objcg)
> @@ -1580,7 +1580,7 @@ bool zswap_load(struct folio *folio)
>  		return false;
>  
>  	if (entry->length)
> -		zswap_decompress(entry, page);
> +		zswap_decompress(entry, folio);
>  	else {
>  		dst = kmap_local_page(page);
>  		zswap_fill_page(dst, entry->value);