Re: [PATCH] tcm_loop: Increase maximum request size

[Bart Van Assche <bvanassche@acm.org>]

On 9/29/22 04:55, Nikos Tsironis wrote:
> Increase the maximum request size for tcm_loop, by setting sg_tablesize
> to SG_MAX_SEGMENTS.
> 
> The current value of 256 for sg_tablesize limits the request size to
> PAGE_SIZE * 256, which for 4K pages is 1MiB.
> 
> Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
> ---
>   drivers/target/loopback/tcm_loop.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/target/loopback/tcm_loop.c b/drivers/target/loopback/tcm_loop.c
> index 4407b56aa6d1..6d7c3ebd8613 100644
> --- a/drivers/target/loopback/tcm_loop.c
> +++ b/drivers/target/loopback/tcm_loop.c
> @@ -308,7 +308,7 @@ static struct scsi_host_template tcm_loop_driver_template = {
>   	.eh_device_reset_handler = tcm_loop_device_reset,
>   	.eh_target_reset_handler = tcm_loop_target_reset,
>   	.this_id		= -1,
> -	.sg_tablesize		= 256,
> +	.sg_tablesize		= SG_MAX_SEGMENTS,
>   	.max_sectors		= 0xFFFF,
>   	.dma_boundary		= PAGE_SIZE - 1,
>   	.module			= THIS_MODULE,

There is more that can be improved for this driver, namely removal of 
the dma_boundary parameter and increasing max_sectors.

Thanks,

Bart.