From patchwork Fri Jun 30 16:07:03 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Druzhinin X-Patchwork-Id: 9820025 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1052260224 for ; Fri, 30 Jun 2017 16:10:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0AD99285EB for ; Fri, 30 Jun 2017 16:10:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F333628676; Fri, 30 Jun 2017 16:10:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 925ED285EB for ; Fri, 30 Jun 2017 16:10:46 +0000 (UTC) Received: from localhost ([::1]:45197 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQyVD-0001Dx-V6 for patchwork-qemu-devel@patchwork.kernel.org; Fri, 30 Jun 2017 12:10:39 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58821) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQySW-0007Oy-NH for qemu-devel@nongnu.org; Fri, 30 Jun 2017 12:07:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dQySR-0006zO-UJ for qemu-devel@nongnu.org; Fri, 30 Jun 2017 12:07:52 -0400 Received: from smtp.ctxuk.citrix.com ([185.25.65.24]:62995 helo=SMTP.EU.CITRIX.COM) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1dQySR-0006vm-K5 for qemu-devel@nongnu.org; Fri, 30 Jun 2017 12:07:47 -0400 X-IronPort-AV: E=Sophos;i="5.40,287,1496102400"; d="scan'208";a="48683288" From: Igor Druzhinin To: , Date: Fri, 30 Jun 2017 17:07:03 +0100 Message-ID: <1498838825-23701-3-git-send-email-igor.druzhinin@citrix.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1498838825-23701-1-git-send-email-igor.druzhinin@citrix.com> References: <1498838825-23701-1-git-send-email-igor.druzhinin@citrix.com> MIME-Version: 1.0 X-ClientProxiedBy: FTLPEX02CAS03.citrite.net (10.13.99.94) To AMSPEX02CL03.citrite.net (10.69.22.127) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 185.25.65.24 Subject: [Qemu-devel] [PATCH 2/4] xen/mapcache: add an ability to create dummy mappings 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: anthony.perard@citrix.com, Igor Druzhinin , sstabellini@kernel.org, paul.durrant@citrix.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Dummys are simple anonymous mappings that are placed instead of regular foreign mappings in certain situations when we need to postpone the actual mapping but still have to give a memory region to QEMU to play with. This is planned to be used for restore on Xen. Signed-off-by: Igor Druzhinin --- hw/i386/xen/xen-mapcache.c | 36 ++++++++++++++++++++++++++++-------- 1 file changed, 28 insertions(+), 8 deletions(-) diff --git a/hw/i386/xen/xen-mapcache.c b/hw/i386/xen/xen-mapcache.c index e60156c..05050de 100644 --- a/hw/i386/xen/xen-mapcache.c +++ b/hw/i386/xen/xen-mapcache.c @@ -150,7 +150,8 @@ void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque) static void xen_remap_bucket(MapCacheEntry *entry, hwaddr size, - hwaddr address_index) + hwaddr address_index, + bool dummy) { uint8_t *vaddr_base; xen_pfn_t *pfns; @@ -177,11 +178,25 @@ static void xen_remap_bucket(MapCacheEntry *entry, pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i; } - vaddr_base = xenforeignmemory_map(xen_fmem, xen_domid, PROT_READ|PROT_WRITE, - nb_pfn, pfns, err); - if (vaddr_base == NULL) { - perror("xenforeignmemory_map"); - exit(-1); + if (!dummy) { + vaddr_base = xenforeignmemory_map(xen_fmem, xen_domid, + PROT_READ|PROT_WRITE, + nb_pfn, pfns, err); + if (vaddr_base == NULL) { + perror("xenforeignmemory_map"); + exit(-1); + } + } else { + /* + * We create dummy mappings where we are unable to create a foreign + * mapping immediately due to certain circumstances (i.e. on resume now) + */ + vaddr_base = mmap(NULL, size, PROT_READ|PROT_WRITE, + MAP_ANON|MAP_SHARED, -1, 0); + if (vaddr_base == NULL) { + perror("mmap"); + exit(-1); + } } entry->vaddr_base = vaddr_base; @@ -211,6 +226,7 @@ static uint8_t *xen_map_cache_unlocked(hwaddr phys_addr, hwaddr size, hwaddr cache_size = size; hwaddr test_bit_size; bool translated = false; + bool dummy = false; tryagain: address_index = phys_addr >> MCACHE_BUCKET_SHIFT; @@ -262,14 +278,14 @@ tryagain: if (!entry) { entry = g_malloc0(sizeof (MapCacheEntry)); pentry->next = entry; - xen_remap_bucket(entry, cache_size, address_index); + xen_remap_bucket(entry, cache_size, address_index, dummy); } else if (!entry->lock) { if (!entry->vaddr_base || entry->paddr_index != address_index || entry->size != cache_size || !test_bits(address_offset >> XC_PAGE_SHIFT, test_bit_size >> XC_PAGE_SHIFT, entry->valid_mapping)) { - xen_remap_bucket(entry, cache_size, address_index); + xen_remap_bucket(entry, cache_size, address_index, dummy); } } @@ -282,6 +298,10 @@ tryagain: translated = true; goto tryagain; } + if (!dummy && runstate_check(RUN_STATE_INMIGRATE)) { + dummy = true; + goto tryagain; + } trace_xen_map_cache_return(NULL); return NULL; }