From patchwork Sun Mar 14 16:21:14 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gleb Natapov X-Patchwork-Id: 85831 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o2EGLtTi019888 for ; Sun, 14 Mar 2010 16:21:56 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932565Ab0CNQVw (ORCPT ); Sun, 14 Mar 2010 12:21:52 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53813 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758530Ab0CNQVV (ORCPT ); Sun, 14 Mar 2010 12:21:21 -0400 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o2EGLK46014538 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 14 Mar 2010 12:21:21 -0400 Received: from dhcp-1-237.tlv.redhat.com (dhcp-1-237.tlv.redhat.com [10.35.1.237]) by int-mx05.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o2EGLJcc023648; Sun, 14 Mar 2010 12:21:20 -0400 Received: by dhcp-1-237.tlv.redhat.com (Postfix, from userid 13519) id B355C18D474; Sun, 14 Mar 2010 18:21:16 +0200 (IST) From: Gleb Natapov To: avi@redhat.com, mtosatti@redhat.com Cc: kvm@vger.kernel.org Subject: [PATCH v2 29/30] KVM: x86 emulator: introduce pio in string read ahead. Date: Sun, 14 Mar 2010 18:21:14 +0200 Message-Id: <1268583675-3101-30-git-send-email-gleb@redhat.com> In-Reply-To: <1268583675-3101-1-git-send-email-gleb@redhat.com> References: <1268583675-3101-1-git-send-email-gleb@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.18 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Sun, 14 Mar 2010 16:21:56 +0000 (UTC) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 7fda16f..b5e12c5 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -151,6 +151,12 @@ struct fetch_cache { unsigned long end; }; +struct read_cache { + u8 data[1024]; + unsigned long pos; + unsigned long end; +}; + struct decode_cache { u8 twobyte; u8 b; @@ -178,6 +184,7 @@ struct decode_cache { void *modrm_ptr; unsigned long modrm_val; struct fetch_cache fetch; + struct read_cache io_read; }; struct x86_emulate_ctxt { diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 5687b06..819245c 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1257,6 +1257,34 @@ done: return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; } +static int pio_in_emulated(struct x86_emulate_ctxt *ctxt, + struct x86_emulate_ops *ops, + unsigned int size, unsigned short port, + void *dest) +{ + struct read_cache *rc = &ctxt->decode.io_read; + + if (rc->pos == rc->end) { /* refill pio read ahead */ + struct decode_cache *c = &ctxt->decode; + unsigned int in_page, n; + unsigned int count = c->rep_prefix ? + address_mask(c, c->regs[VCPU_REGS_RCX]) : 1; + in_page = (ctxt->eflags & EFLG_DF) ? + offset_in_page(c->regs[VCPU_REGS_RDI]) : + PAGE_SIZE - offset_in_page(c->regs[VCPU_REGS_RDI]); + n = min(min(in_page, (unsigned int)sizeof(rc->data)) / size, + count); + rc->pos = rc->end = 0; + if (!ops->pio_in_emulated(size, port, rc->data, n, ctxt->vcpu)) + return 0; + rc->end = n * size; + } + + memcpy(dest, rc->data + rc->pos, size); + rc->pos += size; + return 1; +} + static u32 desc_limit_scaled(struct desc_struct *desc) { u32 limit = get_desc_limit(desc); @@ -2611,8 +2639,8 @@ special_insn: kvm_inject_gp(ctxt->vcpu, 0); goto done; } - if (!ops->pio_in_emulated(c->dst.bytes, c->regs[VCPU_REGS_RDX], - &c->dst.val, 1, ctxt->vcpu)) + if (!pio_in_emulated(ctxt, ops, c->dst.bytes, + c->regs[VCPU_REGS_RDX], &c->dst.val)) goto done; /* IO is needed, skip writeback */ break; case 0x6e: /* outsb */ @@ -2826,8 +2854,7 @@ special_insn: kvm_inject_gp(ctxt->vcpu, 0); goto done; } - ops->pio_in_emulated(c->dst.bytes, c->src.val, &c->dst.val, 1, - ctxt->vcpu); + pio_in_emulated(ctxt, ops, c->dst.bytes, c->src.val, &c->dst.val); break; case 0xee: /* out al,dx */ case 0xef: /* out (e/r)ax,dx */