Re: [PATCH v2 16/16] mt76: use netmem descriptor and APIs for page pool

[Byungchul Park <byungchul@sk.com>]

On Wed, May 28, 2025 at 11:29:11AM +0900, Byungchul Park wrote:
> To simplify struct page, the effort to separate its own descriptor from
> struct page is required and the work for page pool is on going.
> 
> Use netmem descriptor and APIs for page pool in mt76 code.
> 
> Signed-off-by: Byungchul Park <byungchul@sk.com>
> ---
>  drivers/net/wireless/mediatek/mt76/dma.c      |  6 ++---
>  drivers/net/wireless/mediatek/mt76/mt76.h     | 12 +++++-----
>  .../net/wireless/mediatek/mt76/sdio_txrx.c    | 24 +++++++++----------
>  drivers/net/wireless/mediatek/mt76/usb.c      | 10 ++++----
>  4 files changed, 26 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
> index 35b4ec91979e..cceff435ec4a 100644
> --- a/drivers/net/wireless/mediatek/mt76/dma.c
> +++ b/drivers/net/wireless/mediatek/mt76/dma.c
> @@ -820,10 +820,10 @@ mt76_add_fragment(struct mt76_dev *dev, struct mt76_queue *q, void *data,
>  	int nr_frags = shinfo->nr_frags;
>  
>  	if (nr_frags < ARRAY_SIZE(shinfo->frags)) {
> -		struct page *page = virt_to_head_page(data);
> -		int offset = data - page_address(page) + q->buf_offset;
> +		netmem_ref netmem = netmem_compound_head(virt_to_netmem(data));
> +		int offset = data - netmem_address(netmem) + q->buf_offset;
>  
> -		skb_add_rx_frag(skb, nr_frags, page, offset, len, q->buf_size);
> +		skb_add_rx_frag_netmem(skb, nr_frags, netmem, offset, len, q->buf_size);
>  	} else {
>  		mt76_put_page_pool_buf(data, allow_direct);
>  	}
> diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
> index 5f8d81cda6cd..f075c1816554 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt76.h
> +++ b/drivers/net/wireless/mediatek/mt76/mt76.h
> @@ -1795,21 +1795,21 @@ int mt76_rx_token_consume(struct mt76_dev *dev, void *ptr,
>  int mt76_create_page_pool(struct mt76_dev *dev, struct mt76_queue *q);
>  static inline void mt76_put_page_pool_buf(void *buf, bool allow_direct)
>  {
> -	struct page *page = virt_to_head_page(buf);
> +	netmem_ref netmem = netmem_compound_head(virt_to_netmem(buf));
>  
> -	page_pool_put_full_page(page->pp, page, allow_direct);

To Mina,

They touch ->pp field.  That's why I thought they use page pool.  Am I
missing something?

	Byungchul

> +	page_pool_put_full_netmem(netmem_get_pp(netmem), netmem, allow_direct);
>  }
>  
>  static inline void *
>  mt76_get_page_pool_buf(struct mt76_queue *q, u32 *offset, u32 size)
>  {
> -	struct page *page;
> +	netmem_ref netmem;
>  
> -	page = page_pool_dev_alloc_frag(q->page_pool, offset, size);
> -	if (!page)
> +	netmem = page_pool_dev_alloc_netmem(q->page_pool, offset, &size);
> +	if (!netmem)
>  		return NULL;
>  
> -	return page_address(page) + *offset;
> +	return netmem_address(netmem) + *offset;
>  }
>  
>  static inline void mt76_set_tx_blocked(struct mt76_dev *dev, bool blocked)
> diff --git a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
> index 0a927a7313a6..8663070191a1 100644
> --- a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
> +++ b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
> @@ -68,14 +68,14 @@ mt76s_build_rx_skb(void *data, int data_len, int buf_len)
>  
>  	skb_put_data(skb, data, len);
>  	if (data_len > len) {
> -		struct page *page;
> +		netmem_ref netmem;
>  
>  		data += len;
> -		page = virt_to_head_page(data);
> -		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
> -				page, data - page_address(page),
> -				data_len - len, buf_len);
> -		get_page(page);
> +		page = netmem_compound_head(virt_to_netmem(data));
> +		skb_add_rx_frag_netmem(skb, skb_shinfo(skb)->nr_frags,
> +				       netmem, data - netmem_address(netmem),
> +				       data_len - len, buf_len);
> +		get_netmem(netmem);
>  	}
>  
>  	return skb;
> @@ -88,7 +88,7 @@ mt76s_rx_run_queue(struct mt76_dev *dev, enum mt76_rxq_id qid,
>  	struct mt76_queue *q = &dev->q_rx[qid];
>  	struct mt76_sdio *sdio = &dev->sdio;
>  	int len = 0, err, i;
> -	struct page *page;
> +	netmem_ref netmem;
>  	u8 *buf, *end;
>  
>  	for (i = 0; i < intr->rx.num[qid]; i++)
> @@ -100,11 +100,11 @@ mt76s_rx_run_queue(struct mt76_dev *dev, enum mt76_rxq_id qid,
>  	if (len > sdio->func->cur_blksize)
>  		len = roundup(len, sdio->func->cur_blksize);
>  
> -	page = __dev_alloc_pages(GFP_KERNEL, get_order(len));
> -	if (!page)
> +	netmem = page_to_netmem(__dev_alloc_pages(GFP_KERNEL, get_order(len)));
> +	if (!netmem)
>  		return -ENOMEM;
>  
> -	buf = page_address(page);
> +	buf = netmem_address(netmem);
>  
>  	sdio_claim_host(sdio->func);
>  	err = sdio_readsb(sdio->func, buf, MCR_WRDR(qid), len);
> @@ -112,7 +112,7 @@ mt76s_rx_run_queue(struct mt76_dev *dev, enum mt76_rxq_id qid,
>  
>  	if (err < 0) {
>  		dev_err(dev->dev, "sdio read data failed:%d\n", err);
> -		put_page(page);
> +		put_netmem(netmem);
>  		return err;
>  	}
>  
> @@ -140,7 +140,7 @@ mt76s_rx_run_queue(struct mt76_dev *dev, enum mt76_rxq_id qid,
>  		}
>  		buf += round_up(len + 4, 4);
>  	}
> -	put_page(page);
> +	put_netmem(netmem);
>  
>  	spin_lock_bh(&q->lock);
>  	q->head = (q->head + i) % q->ndesc;
> diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c
> index f9e67b8c3b3c..03f0d35981c9 100644
> --- a/drivers/net/wireless/mediatek/mt76/usb.c
> +++ b/drivers/net/wireless/mediatek/mt76/usb.c
> @@ -478,7 +478,7 @@ mt76u_build_rx_skb(struct mt76_dev *dev, void *data,
>  
>  	head_room = drv_flags & MT_DRV_RX_DMA_HDR ? 0 : MT_DMA_HDR_LEN;
>  	if (SKB_WITH_OVERHEAD(buf_size) < head_room + len) {
> -		struct page *page;
> +		netmem_ref netmem;
>  
>  		/* slow path, not enough space for data and
>  		 * skb_shared_info
> @@ -489,10 +489,10 @@ mt76u_build_rx_skb(struct mt76_dev *dev, void *data,
>  
>  		skb_put_data(skb, data + head_room, MT_SKB_HEAD_LEN);
>  		data += head_room + MT_SKB_HEAD_LEN;
> -		page = virt_to_head_page(data);
> -		skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
> -				page, data - page_address(page),
> -				len - MT_SKB_HEAD_LEN, buf_size);
> +		netmem = netmem_compound_head(virt_to_netmem(data));
> +		skb_add_rx_frag_netmem(skb, skb_shinfo(skb)->nr_frags,
> +				       netmem, data - netmem_address(netmem),
> +				       len - MT_SKB_HEAD_LEN, buf_size);
>  
>  		return skb;
>  	}
> -- 
> 2.17.1