Subject: Re: [PATCH net-next 3/3] bnxt_en: Let the page pool manage the DMA mapping

From: Jakub Kicinski <[email-masked]>
Date: Fri, 28 Jul 2023 17:42:12 -0700

On Fri, 28 Jul 2023 16:18:29 -0700 Michael Chan wrote:
> +	pp.dma_dir = bp->rx_dir;
> +	pp.max_len = BNXT_RX_PAGE_SIZE;

I _think_ you need PAGE_SIZE here.

This should be smaller than PAGE_SIZE only if you're wasting the rest
of the buffer, e.g. MTU is 3k so you know last 1k will never get used.
PAGE_SIZE is always a multiple of BNXT_RX_PAGE so you waste nothing.

Adding Jesper to CC to keep me honest.

> +	pp.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV;