From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30B23C28CC0 for ; Wed, 29 May 2019 09:04:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11C2D20B7C for ; Wed, 29 May 2019 09:04:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726599AbfE2JEW (ORCPT ); Wed, 29 May 2019 05:04:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:46210 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726121AbfE2JEM (ORCPT ); Wed, 29 May 2019 05:04:12 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 0AFA7AEFD; Wed, 29 May 2019 09:04:11 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: Juergen Gross , Konrad Rzeszutek Wilk , Boris Ostrovsky , Stefano Stabellini , xen-devel@lists.xenproject.org Subject: [PATCH v2 3/3] xen/swiotlb: remember having called xen_create_contiguous_region() Date: Wed, 29 May 2019 11:04:07 +0200 Message-Id: <20190529090407.1225-4-jgross@suse.com> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190529090407.1225-1-jgross@suse.com> References: <20190529090407.1225-1-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Instead of always calling xen_destroy_contiguous_region() in case the memory is DMA-able for the used device, do so only in case it has been made DMA-able via xen_create_contiguous_region() before. This will avoid a lot of xen_destroy_contiguous_region() calls for 64-bit capable devices. As the memory in question is owned by swiotlb-xen the PG_owner_priv_1 flag of the first allocated page can be used for remembering. Signed-off-by: Juergen Gross --- V2: add PG_xen_remapped alias for PG_owner_priv_1 (Boris Ostrovsky) only clear page flag in case of sane conditions (Jan Beulich) --- drivers/xen/swiotlb-xen.c | 6 +++++- include/linux/page-flags.h | 3 +++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index aba5247b9145..7e2d9d1b6f63 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -321,6 +321,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs); return NULL; } + SetPageXenRemapped(virt_to_page(ret)); } memset(ret, 0, size); return ret; @@ -345,8 +346,11 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, size = 1UL << (order + XEN_PAGE_SHIFT); if (!WARN_ON((dev_addr + size - 1 > dma_mask) || - range_straddles_page_boundary(phys, size))) + range_straddles_page_boundary(phys, size)) && + PageXenRemapped(virt_to_page(vaddr))) { xen_destroy_contiguous_region(phys, order); + ClearPageXenRemapped(virt_to_page(vaddr)); + } xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); } diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 9f8712a4b1a5..296480e990f2 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -152,6 +152,8 @@ enum pageflags { PG_savepinned = PG_dirty, /* Has a grant mapping of another (foreign) domain's page. */ PG_foreign = PG_owner_priv_1, + /* Remapped by swiotlb-xen. */ + PG_xen_remapped = PG_owner_priv_1, /* SLOB */ PG_slob_free = PG_private, @@ -329,6 +331,7 @@ PAGEFLAG(Pinned, pinned, PF_NO_COMPOUND) TESTSCFLAG(Pinned, pinned, PF_NO_COMPOUND) PAGEFLAG(SavePinned, savepinned, PF_NO_COMPOUND); PAGEFLAG(Foreign, foreign, PF_NO_COMPOUND); +PAGEFLAG(XenRemapped, xen_remapped, PF_NO_COMPOUND); PAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) __CLEARPAGEFLAG(Reserved, reserved, PF_NO_COMPOUND) -- 2.16.4