From patchwork Wed Nov 15 07:14:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiaoyao Li X-Patchwork-Id: 13456254 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C6D42C07548 for ; Wed, 15 Nov 2023 07:17:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r3A8h-0006MV-Pz; Wed, 15 Nov 2023 02:16:43 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r3A8g-0006Dx-3t for qemu-devel@nongnu.org; Wed, 15 Nov 2023 02:16:42 -0500 Received: from mgamail.intel.com ([192.55.52.115]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1r3A8e-0002JU-8I for qemu-devel@nongnu.org; Wed, 15 Nov 2023 02:16:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700032600; x=1731568600; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=d8m/K4WT12hdYcKmOmyFhEUCYXWBDBTjG/rXpGvxHMU=; b=Vs+dI9eV1xY2m+5nQpwHdgYDnbc07gph2A1y7w+BhSsvYqKSw1kT8T8b jwGUOBPDbjsgiwxgdllY7+X2BD70OWp34hGygeVQUyPcsR9UhvBhg1P/T yN1wfvCh1IFhkOfTtzvky4GHt/o6TRTeNyGv2Ho1t+6PU8tggg8y3sqMb MMQ5WDYdjxmG4oA3DzxZC9AIL+KbiAdlSrrp7oSOkYSKKad57edblVAzQ ebPFsvYSwzfBmvOTVygGAZYJcpIGj5H0KjzSbic/DSaepZPTAA6LAskpx JZ1pithN5QuJc2BeDWD4Qsq+tXdtlEaiUDlk3QqcAqPiDkRHhxA4BeP4z w==; X-IronPort-AV: E=McAfee;i="6600,9927,10894"; a="390622253" X-IronPort-AV: E=Sophos;i="6.03,304,1694761200"; d="scan'208";a="390622253" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Nov 2023 23:16:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10894"; a="714797186" X-IronPort-AV: E=Sophos;i="6.03,304,1694761200"; d="scan'208";a="714797186" Received: from lxy-clx-4s.sh.intel.com ([10.239.48.52]) by orsmga003.jf.intel.com with ESMTP; 14 Nov 2023 23:16:30 -0800 From: Xiaoyao Li To: Paolo Bonzini , David Hildenbrand , Igor Mammedov , "Michael S . Tsirkin" , Marcel Apfelbaum , Richard Henderson , Peter Xu , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Cornelia Huck , =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= , Eric Blake , Markus Armbruster , Marcelo Tosatti Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org, xiaoyao.li@intel.com, Michael Roth , Sean Christopherson , Claudio Fontana , Gerd Hoffmann , Isaku Yamahata , Chenyi Qiang Subject: [PATCH v3 09/70] physmem: Introduce ram_block_convert_range() for page conversion Date: Wed, 15 Nov 2023 02:14:18 -0500 Message-Id: <20231115071519.2864957-10-xiaoyao.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231115071519.2864957-1-xiaoyao.li@intel.com> References: <20231115071519.2864957-1-xiaoyao.li@intel.com> MIME-Version: 1.0 Received-SPF: pass client-ip=192.55.52.115; envelope-from=xiaoyao.li@intel.com; helo=mgamail.intel.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HK_RANDOM_ENVFROM=0.999, HK_RANDOM_FROM=0.999, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org It's used for discarding opposite memory after memory conversion, for confidential guest. When page is converted from shared to private, the original shared memory can be discarded via ram_block_discard_range(); When page is converted from private to shared, the original private memory is back'ed by guest_memfd. Introduce ram_block_discard_guest_memfd_range() for discarding memory in guest_memfd. Originally-from: Isaku Yamahata Codeveloped-by: Xiaoyao Li Signed-off-by: Xiaoyao Li --- include/exec/cpu-common.h | 2 ++ system/physmem.c | 50 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+) diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h index 41115d891940..de728a18eef2 100644 --- a/include/exec/cpu-common.h +++ b/include/exec/cpu-common.h @@ -175,6 +175,8 @@ typedef int (RAMBlockIterFunc)(RAMBlock *rb, void *opaque); int qemu_ram_foreach_block(RAMBlockIterFunc func, void *opaque); int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length); +int ram_block_convert_range(RAMBlock *rb, uint64_t start, size_t length, + bool shared_to_private); #endif diff --git a/system/physmem.c b/system/physmem.c index ddfecddefcd6..cd6008fa09ad 100644 --- a/system/physmem.c +++ b/system/physmem.c @@ -3641,6 +3641,29 @@ err: return ret; } +static int ram_block_discard_guest_memfd_range(RAMBlock *rb, uint64_t start, + size_t length) +{ + int ret = -1; + +#ifdef CONFIG_FALLOCATE_PUNCH_HOLE + ret = fallocate(rb->guest_memfd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, + start, length); + + if (ret) { + ret = -errno; + error_report("%s: Failed to fallocate %s:%" PRIx64 " +%zx (%d)", + __func__, rb->idstr, start, length, ret); + } +#else + ret = -ENOSYS; + error_report("%s: fallocate not available %s:%" PRIx64 " +%zx (%d)", + __func__, rb->idstr, start, length, ret); +#endif + + return ret; +} + bool ramblock_is_pmem(RAMBlock *rb) { return rb->flags & RAM_PMEM; @@ -3828,3 +3851,30 @@ bool ram_block_discard_is_required(void) return qatomic_read(&ram_block_discard_required_cnt) || qatomic_read(&ram_block_coordinated_discard_required_cnt); } + +int ram_block_convert_range(RAMBlock *rb, uint64_t start, size_t length, + bool shared_to_private) +{ + if (!rb || rb->guest_memfd < 0) { + return -1; + } + + if (!QEMU_PTR_IS_ALIGNED(start, qemu_host_page_size) || + !QEMU_PTR_IS_ALIGNED(length, qemu_host_page_size)) { + return -1; + } + + if (!length) { + return -1; + } + + if (start + length > rb->max_length) { + return -1; + } + + if (shared_to_private) { + return ram_block_discard_range(rb, start, length); + } else { + return ram_block_discard_guest_memfd_range(rb, start, length); + } +}