From patchwork Sat May 30 10:59:24 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 6512831 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 492DF9F1C1 for ; Sat, 30 May 2015 11:02:19 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6726420851 for ; Sat, 30 May 2015 11:02:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 73A8B20850 for ; Sat, 30 May 2015 11:02:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932558AbbE3LB5 (ORCPT ); Sat, 30 May 2015 07:01:57 -0400 Received: from mga11.intel.com ([192.55.52.93]:40825 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757805AbbE3K7x (ORCPT ); Sat, 30 May 2015 06:59:53 -0400 Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP; 30 May 2015 03:59:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,522,1427785200"; d="scan'208";a="717943279" Received: from slu40-mobl2.ccr.corp.intel.com (HELO homedesktop.ccr.corp.intel.com) ([10.254.212.183]) by fmsmga001.fm.intel.com with ESMTP; 30 May 2015 03:59:50 -0700 From: Xiao Guangrong To: pbonzini@redhat.com Cc: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Xiao Guangrong Subject: [PATCH 13/15] KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type Date: Sat, 30 May 2015 18:59:24 +0800 Message-Id: <1432983566-15773-14-git-send-email-guangrong.xiao@linux.intel.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1432983566-15773-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1432983566-15773-1-git-send-email-guangrong.xiao@linux.intel.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP mtrr_for_each_mem_type() is ready now, use it to simplify kvm_mtrr_get_guest_memory_type() Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mtrr.c | 61 +++++++++++++---------------------------------------- 1 file changed, 15 insertions(+), 46 deletions(-) diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index 35f86303..bc90834 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -581,56 +581,19 @@ static void mtrr_lookup_next(struct mtrr_looker *looker) u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) { struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; - u64 base, mask, start = gfn_to_gpa(gfn); - int i, num_var_ranges = KVM_NR_VAR_MTRR, type_mask, type = -1; - - /* MTRR is completely disabled, use UC for all of physical memory. */ - if (!mtrr_state->mtrr_enabled) - return MTRR_TYPE_UNCACHABLE; - - /* Look in fixed ranges. Just return the type as per start */ - if (mtrr_state->fixed_mtrr_enabled && (start < 0x100000)) { - int idx; - - if (start < 0x80000) { - idx = 0; - idx += (start >> 16); - return mtrr_state->fixed_ranges[idx]; - } else if (start < 0xC0000) { - idx = 1 * 8; - idx += ((start - 0x80000) >> 14); - return mtrr_state->fixed_ranges[idx]; - } else if (start < 0x1000000) { - idx = 3 * 8; - idx += ((start - 0xC0000) >> 12); - return mtrr_state->fixed_ranges[idx]; - } - } + struct mtrr_looker looker; + u64 start = gfn_to_gpa(gfn), end = start + PAGE_SIZE; + int type_mask, type = -1; - /* - * Look in variable ranges - * Look of multiple ranges matching this address and pick type - * as per MTRR precedence - */ type_mask = (1 << MTRR_TYPE_WRBACK) | (1 << MTRR_TYPE_WRTHROUGH); - for (i = 0; i < num_var_ranges; ++i) { - int curr_type; - - if (!(mtrr_state->var_ranges[i].mask & (1 << 11))) - continue; - - base = mtrr_state->var_ranges[i].base & PAGE_MASK; - mask = mtrr_state->var_ranges[i].mask & PAGE_MASK; - - if ((start & mask) != (base & mask)) - continue; + mtrr_for_each_mem_type(&looker, mtrr_state, start, end) { + int curr_type = looker.mem_type; /* * Please refer to Intel SDM Volume 3: 11.11.4.1 MTRR * Precedences. */ - curr_type = mtrr_state->var_ranges[i].base & 0xff; if (type == -1) { type = curr_type; continue; @@ -670,9 +633,15 @@ u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) return MTRR_TYPE_WRBACK; } - if (type != -1) - return type; - - return mtrr_state->def_type; + /* It is not covered by MTRRs. */ + if (looker.partial_map) { + /* + * We just check one page, partially covered by MTRRs is + * impossible. + */ + WARN_ON(type != -1); + type = mtrr_state->def_type; + } + return type; } EXPORT_SYMBOL_GPL(kvm_mtrr_get_guest_memory_type);