Commit 3e7b52e0 authored Sep 19, 2022 by Anirudh Venkataramanan Committed by Tony Nguyen Nov 02, 2022

e1000: Remove unnecessary use of kmap_atomic()



buffer_info->rxbuf.page accessed in e1000_clean_jumbo_rx_irq() is
allocated using GFP_ATOMIC. Pages allocated with GFP_ATOMIC can't come from
highmem and so there's no need to kmap() them. Just use page_address().

I don't have access to a 32-bit system so did some limited testing on
qemu (qemu-system-i386 -m 4096 -smp 4 -device e1000e) with a 32-bit
Debian 11.04 image.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

parent ab400b0d

drivers/net/ethernet/intel/e1000/e1000_main.c

+3 −6

Original line number	Diff line number	Diff line
		@@ -4229,8 +4229,6 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
		*/
		p = buffer_info->rxbuf.page;
		if (length <= copybreak) {
		u8 *vaddr;

		if (likely(!(netdev->features & NETIF_F_RXFCS)))
		length -= 4;
		skb = e1000_alloc_rx_skb(adapter,
		@@ -4238,10 +4236,9 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
		if (!skb)
		break;

		vaddr = kmap_atomic(p);
		memcpy(skb_tail_pointer(skb), vaddr,
		length);
		kunmap_atomic(vaddr);
		memcpy(skb_tail_pointer(skb),
		page_address(p), length);

		/* re-use the page, so don't erase
		* buffer_info->rxbuf.page
		*/