From patchwork Tue May 22 18:46:38 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 918528 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="c8KEb30Q"; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40r4Tz0p4Mz9s2L for ; Wed, 23 May 2018 04:50:47 +1000 (AEST) Received: from localhost ([::1]:57347 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fLCMu-000414-L3 for incoming@patchwork.ozlabs.org; Tue, 22 May 2018 14:50:44 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50747) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fLCJ9-0001fD-1v for qemu-devel@nongnu.org; Tue, 22 May 2018 14:46:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fLCJ6-0007Rn-8b for qemu-devel@nongnu.org; Tue, 22 May 2018 14:46:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:43618) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fLCJ5-0007RF-WE for qemu-devel@nongnu.org; Tue, 22 May 2018 14:46:48 -0400 Received: from sstabellini-ThinkPad-X260.xilinx.com (unknown [149.199.62.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E33362087B; Tue, 22 May 2018 18:46:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1527014807; bh=bgAD0hHlztPXWtZZJwLpY9OhXzf2Hp8xmt6waTOjqF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c8KEb30QXs4P4KmCb9CzzvsR0hAdbmGvz6Xc68kBLx+bPg1apuyH5ZV1thMzlABp/ zGfY7jXicR8cjIMafeOabrj9lFS7ggcp5qk4TCwDeZNpYp2r6E1Cd4bB3Q7MxCZXPT /ZF7EDov6/x6R0cbYb5mnEos5cVVTcT5JGBLQpD0= From: Stefano Stabellini To: peter.maydell@linaro.org, stefanha@gmail.com Date: Tue, 22 May 2018 11:46:38 -0700 Message-Id: <1527014802-11289-11-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 198.145.29.99 Subject: [Qemu-devel] [PULL v2 11/15] xen_backend: add an emulation of grant copy X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: sstabellini@kernel.org, qemu-devel@nongnu.org, Paul Durrant , stefanha@redhat.com, anthony.perard@citrix.com, xen-devel@lists.xenproject.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Paul Durrant Not all Xen environments support the xengnttab_grant_copy() operation. E.g. where the OS is FreeBSD or Xen is older than 4.8.0. This patch introduces an emulation of that operation using xengnttab_map_domain_grant_refs() and memcpy() for those environments. Signed-off-by: Paul Durrant Acked-by: Anthony PERARD Signed-off-by: Stefano Stabellini --- hw/xen/xen_backend.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c index 50412d6..3c3fc2c 100644 --- a/hw/xen/xen_backend.c +++ b/hw/xen/xen_backend.c @@ -146,6 +146,55 @@ void xen_be_unmap_grant_refs(struct XenDevice *xendev, void *ptr, } } +static int compat_copy_grant_refs(struct XenDevice *xendev, + bool to_domain, + XenGrantCopySegment segs[], + unsigned int nr_segs) +{ + uint32_t *refs = g_new(uint32_t, nr_segs); + int prot = to_domain ? PROT_WRITE : PROT_READ; + void *pages; + unsigned int i; + + for (i = 0; i < nr_segs; i++) { + XenGrantCopySegment *seg = &segs[i]; + + refs[i] = to_domain ? + seg->dest.foreign.ref : seg->source.foreign.ref; + } + + pages = xengnttab_map_domain_grant_refs(xendev->gnttabdev, nr_segs, + xen_domid, refs, prot); + if (!pages) { + xen_pv_printf(xendev, 0, + "xengnttab_map_domain_grant_refs failed: %s\n", + strerror(errno)); + g_free(refs); + return -1; + } + + for (i = 0; i < nr_segs; i++) { + XenGrantCopySegment *seg = &segs[i]; + void *page = pages + (i * XC_PAGE_SIZE); + + if (to_domain) { + memcpy(page + seg->dest.foreign.offset, seg->source.virt, + seg->len); + } else { + memcpy(seg->dest.virt, page + seg->source.foreign.offset, + seg->len); + } + } + + if (xengnttab_unmap(xendev->gnttabdev, pages, nr_segs)) { + xen_pv_printf(xendev, 0, "xengnttab_unmap failed: %s\n", + strerror(errno)); + } + + g_free(refs); + return 0; +} + int xen_be_copy_grant_refs(struct XenDevice *xendev, bool to_domain, XenGrantCopySegment segs[], @@ -157,6 +206,10 @@ int xen_be_copy_grant_refs(struct XenDevice *xendev, assert(xendev->ops->flags & DEVOPS_FLAG_NEED_GNTDEV); + if (!xen_feature_grant_copy) { + return compat_copy_grant_refs(xendev, to_domain, segs, nr_segs); + } + xengnttab_segs = g_new0(xengnttab_grant_copy_segment_t, nr_segs); for (i = 0; i < nr_segs; i++) {