From patchwork Wed Nov 23 20:52:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anirudh Venkataramanan X-Patchwork-Id: 13054279 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DA4C1C4332F for ; Wed, 23 Nov 2022 20:51:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237472AbiKWUvg (ORCPT ); Wed, 23 Nov 2022 15:51:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235426AbiKWUvP (ORCPT ); Wed, 23 Nov 2022 15:51:15 -0500 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C47636BDF3 for ; Wed, 23 Nov 2022 12:51:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1669236674; x=1700772674; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ED1M1kq/YLs3tO8iY0cVBj6iLOgVN3mxVZze6U7DGKw=; b=cn9csYvr5f7hJED8cVQ6b0j1asvDKXJIR3OoRFlXt4duQPpPlMtAuap/ VzHOG4u5u9JioE+RevsM2c1XoUcBUNo4nW2h4t6oyxDSu8d5KgQd5fyz7 r8dtAuzHRbDhZP+vvX5Ia5NTUqN3zJ+qD6V/136Rm4911e9PFvBgHZvMu hZxdaKmD4A0FLp+xYL1/zP2NlF/khydNROo9pl7XiwoSHHN9mhahGf1DG HwhPZjt1RcRMkneFw0zfREfJhXeZID9aiNM7U+jTDAdjU+B18E701GO07 TgOGqGMFZCcTNwh4Nl1UMD8sJFq0B6XsLbctyXozG9xDe2hX0404yHe7o A==; X-IronPort-AV: E=McAfee;i="6500,9779,10540"; a="293862669" X-IronPort-AV: E=Sophos;i="5.96,187,1665471600"; d="scan'208";a="293862669" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Nov 2022 12:51:13 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10540"; a="747947698" X-IronPort-AV: E=Sophos;i="5.96,187,1665471600"; d="scan'208";a="747947698" Received: from avenkata-desk0.sc.intel.com ([172.25.112.42]) by fmsmga002.fm.intel.com with ESMTP; 23 Nov 2022 12:51:12 -0800 From: Anirudh Venkataramanan To: netdev@vger.kernel.org Cc: Ira Weiny , "Fabio M . De Francesco" , Anirudh Venkataramanan Subject: [PATCH v2 net-next 3/6] cassini: Use page_address() instead of kmap_atomic() Date: Wed, 23 Nov 2022 12:52:16 -0800 Message-Id: <20221123205219.31748-4-anirudh.venkataramanan@intel.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221123205219.31748-1-anirudh.venkataramanan@intel.com> References: <20221123205219.31748-1-anirudh.venkataramanan@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Pages for Rx buffers are allocated in cas_page_alloc() using either GFP_ATOMIC or GFP_KERNEL. Memory allocated with GFP_KERNEL/GFP_ATOMIC can't come from highmem and so there's no need to kmap() them. Just use page_address() instead. This makes the variable 'addr' unnecessary, so remove it too. Note that kmap_atomic() disables preemption and page-fault processing, but page_address() doesn't. When removing uses of kmap_atomic(), one has to check if the code being executed between the map/unmap implicitly depends on page-faults and/or preemption being disabled. If yes, then code to disable page-faults and/or preemption should also be added for functional correctness. That however doesn't appear to be the case here, so just page_address() is used. I don't have hardware, so this change has only been compile tested. Cc: Ira Weiny Cc: Fabio M. De Francesco Signed-off-by: Anirudh Venkataramanan Reviewed-by: Fabio M. De Francesco --- v1 -> v2: Update commit message --- drivers/net/ethernet/sun/cassini.c | 34 ++++++++++-------------------- 1 file changed, 11 insertions(+), 23 deletions(-) diff --git a/drivers/net/ethernet/sun/cassini.c b/drivers/net/ethernet/sun/cassini.c index 0aca193..2f66cfc 100644 --- a/drivers/net/ethernet/sun/cassini.c +++ b/drivers/net/ethernet/sun/cassini.c @@ -1915,7 +1915,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, int off, swivel = RX_SWIVEL_OFF_VAL; struct cas_page *page; struct sk_buff *skb; - void *addr, *crcaddr; + void *crcaddr; __sum16 csum; char *p; @@ -1936,7 +1936,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, skb_reserve(skb, swivel); p = skb->data; - addr = crcaddr = NULL; + crcaddr = NULL; if (hlen) { /* always copy header pages */ i = CAS_VAL(RX_COMP2_HDR_INDEX, words[1]); page = cp->rx_pages[CAS_VAL(RX_INDEX_RING, i)][CAS_VAL(RX_INDEX_NUM, i)]; @@ -1948,12 +1948,10 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, i += cp->crc_size; dma_sync_single_for_cpu(&cp->pdev->dev, page->dma_addr + off, i, DMA_FROM_DEVICE); - addr = cas_page_map(page->buffer); - memcpy(p, addr + off, i); + memcpy(p, page_address(page->buffer) + off, i); dma_sync_single_for_device(&cp->pdev->dev, page->dma_addr + off, i, DMA_FROM_DEVICE); - cas_page_unmap(addr); RX_USED_ADD(page, 0x100); p += hlen; swivel = 0; @@ -1984,12 +1982,11 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, /* make sure we always copy a header */ swivel = 0; if (p == (char *) skb->data) { /* not split */ - addr = cas_page_map(page->buffer); - memcpy(p, addr + off, RX_COPY_MIN); + memcpy(p, page_address(page->buffer) + off, + RX_COPY_MIN); dma_sync_single_for_device(&cp->pdev->dev, page->dma_addr + off, i, DMA_FROM_DEVICE); - cas_page_unmap(addr); off += RX_COPY_MIN; swivel = RX_COPY_MIN; RX_USED_ADD(page, cp->mtu_stride); @@ -2036,10 +2033,8 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, RX_USED_ADD(page, hlen + cp->crc_size); } - if (cp->crc_size) { - addr = cas_page_map(page->buffer); - crcaddr = addr + off + hlen; - } + if (cp->crc_size) + crcaddr = page_address(page->buffer) + off + hlen; } else { /* copying packet */ @@ -2061,12 +2056,10 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, i += cp->crc_size; dma_sync_single_for_cpu(&cp->pdev->dev, page->dma_addr + off, i, DMA_FROM_DEVICE); - addr = cas_page_map(page->buffer); - memcpy(p, addr + off, i); + memcpy(p, page_address(page->buffer) + off, i); dma_sync_single_for_device(&cp->pdev->dev, page->dma_addr + off, i, DMA_FROM_DEVICE); - cas_page_unmap(addr); if (p == (char *) skb->data) /* not split */ RX_USED_ADD(page, cp->mtu_stride); else @@ -2081,20 +2074,17 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, page->dma_addr, dlen + cp->crc_size, DMA_FROM_DEVICE); - addr = cas_page_map(page->buffer); - memcpy(p, addr, dlen + cp->crc_size); + memcpy(p, page_address(page->buffer), dlen + cp->crc_size); dma_sync_single_for_device(&cp->pdev->dev, page->dma_addr, dlen + cp->crc_size, DMA_FROM_DEVICE); - cas_page_unmap(addr); RX_USED_ADD(page, dlen + cp->crc_size); } end_copy_pkt: - if (cp->crc_size) { - addr = NULL; + if (cp->crc_size) crcaddr = skb->data + alloclen; - } + skb_put(skb, alloclen); } @@ -2103,8 +2093,6 @@ static int cas_rx_process_pkt(struct cas *cp, struct cas_rx_comp *rxc, /* checksum includes FCS. strip it out. */ csum = csum_fold(csum_partial(crcaddr, cp->crc_size, csum_unfold(csum))); - if (addr) - cas_page_unmap(addr); } skb->protocol = eth_type_trans(skb, cp->dev); if (skb->protocol == htons(ETH_P_IP)) {