Re: [PATCH v9 6/7] scsi: libiscsi: use sendpage_ok() in iscsi_tcp_segment_map()

[Lee Duncan]

On 10/1/20 12:54 AM, Coly Li wrote:
> In iscsci driver, iscsi_tcp_segment_map() uses the following code to
> check whether the page should or not be handled by sendpage:
>     if (!recv && page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)))
> 
> The "page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)" part is to
> make sure the page can be sent to network layer's zero copy path. This
> part is exactly what sendpage_ok() does.
> 
> This patch uses  use sendpage_ok() in iscsi_tcp_segment_map() to replace
> the original open coded checks.
> 
> Signed-off-by: Coly Li <colyli@xxxxxxx>
> Acked-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
> Cc: Vasily Averin <vvs@xxxxxxxxxxxxx>
> Cc: Cong Wang <amwang@xxxxxxxxxx>
> Cc: Mike Christie <michaelc@xxxxxxxxxxx>
> Cc: Lee Duncan <lduncan@xxxxxxxx>
> Cc: Chris Leech <cleech@xxxxxxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxx>
> Cc: Hannes Reinecke <hare@xxxxxxx>
> ---
>  drivers/scsi/libiscsi_tcp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c
> index 37e5d4e48c2f..83f14b2c8804 100644
> --- a/drivers/scsi/libiscsi_tcp.c
> +++ b/drivers/scsi/libiscsi_tcp.c
> @@ -128,7 +128,7 @@ static void iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
>  	 * coalescing neighboring slab objects into a single frag which
>  	 * triggers one of hardened usercopy checks.
>  	 */
> -	if (!recv && page_count(sg_page(sg)) >= 1 && !PageSlab(sg_page(sg)))
> +	if (!recv && sendpage_ok(sg_page(sg)))
>  		return;
>  
>  	if (recv) {
> 

Reviewed-by: Lee Duncan <lduncan@xxxxxxxx>