From patchwork Tue Nov 5 17:22:05 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 288592 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 86F162C033C for ; Wed, 6 Nov 2013 04:22:44 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754825Ab3KERWl (ORCPT ); Tue, 5 Nov 2013 12:22:41 -0500 Received: from e06smtp11.uk.ibm.com ([195.75.94.107]:41003 "EHLO e06smtp11.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752976Ab3KERWi (ORCPT ); Tue, 5 Nov 2013 12:22:38 -0500 Received: from /spool/local by e06smtp11.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 5 Nov 2013 17:22:35 -0000 Received: from b06cxnps3075.portsmouth.uk.ibm.com (d06relay10.portsmouth.uk.ibm.com [9.149.109.195]) by d06dlp01.portsmouth.uk.ibm.com (Postfix) with ESMTP id E5F7817D8057; Tue, 5 Nov 2013 17:22:11 +0000 (GMT) Received: from d06av06.portsmouth.uk.ibm.com (d06av06.portsmouth.uk.ibm.com [9.149.37.217]) by b06cxnps3075.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id rA5HMMvn60948506; Tue, 5 Nov 2013 17:22:22 GMT Received: from d06av06.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av06.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id rA5HMYwH027887; Tue, 5 Nov 2013 10:22:34 -0700 Received: from smtp.lab.toulouse-stg.fr.ibm.com (srv01.lab.toulouse-stg.fr.ibm.com [9.101.4.1]) by d06av06.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id rA5HMYkL027884; Tue, 5 Nov 2013 10:22:34 -0700 Received: from hermes.lab.toulouse-stg.fr.ibm.com (hermes.lab.toulouse-stg.fr.ibm.com [9.101.4.42]) by smtp.lab.toulouse-stg.fr.ibm.com (Postfix) with ESMTP id F3AA3210FFE; Tue, 5 Nov 2013 18:22:33 +0100 (CET) From: =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= To: agraf@suse.de, paulus@samba.org Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, =?UTF-8?q?C=C3=A9dric=20Le=20Goater?= Subject: [PATCH v5 3/6] KVM: PPC: Book3S: MMIO emulation support for little endian guests Date: Tue, 5 Nov 2013 18:22:05 +0100 Message-Id: <1383672128-26795-4-git-send-email-clg@fr.ibm.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1383672128-26795-1-git-send-email-clg@fr.ibm.com> References: <1383672128-26795-1-git-send-email-clg@fr.ibm.com> In-Reply-To: <84018BDE-858B-4F59-8AA0-9135CCFF4720@suse.de> References: <84018BDE-858B-4F59-8AA0-9135CCFF4720@suse.de> MIME-Version: 1.0 X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13110517-5024-0000-0000-000007BA638B Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org MMIO emulation reads the last instruction executed by the guest and then emulates. If the guest is running in Little Endian mode, the instruction needs to be byte-swapped before being emulated. This patch stores the last instruction in the endian order of the host, primarily doing a byte-swap if needed. The common code which fetches 'last_inst' uses a helper routine kvmppc_need_byteswap(). and the exit paths for the Book3S PV and HR guests use their own version in assembly. Finally, the meaning of the 'is_bigendian' argument of the routines kvmppc_handle_load() of kvmppc_handle_store() is slightly changed to represent an eventual reverse operation. This is used in conjunction with kvmppc_is_bigendian() to determine if the instruction being emulated should be byte-swapped. Signed-off-by: Cédric Le Goater Signed-off-by: Paul Mackerras --- Changes in v5: - changed register usage slightly (paulus@samba.org) - added #ifdef CONFIG_PPC64 in book3s_segment.S (paulus@samba.org) Changes in v3: - moved kvmppc_need_byteswap() in kvmppc_ld32. It previously was in kvmppc_ld_inst(). (Alexander Graf) Changes in v2: - replaced rldicl. by andi. to test the MSR_LE bit in the guest exit paths. (Paul Mackerras) - moved the byte swapping logic to kvmppc_handle_load() and kvmppc_handle_load() by changing the is_bigendian parameter meaning. (Paul Mackerras) arch/powerpc/include/asm/kvm_book3s.h | 9 ++++++++- arch/powerpc/include/asm/kvm_ppc.h | 10 +++++----- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 9 +++++++++ arch/powerpc/kvm/book3s_segment.S | 9 +++++++++ arch/powerpc/kvm/emulate.c | 1 - arch/powerpc/kvm/powerpc.c | 16 ++++++++++++---- 6 files changed, 43 insertions(+), 11 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 22ec875..ac06434 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -283,7 +283,14 @@ static inline bool kvmppc_is_bigendian(struct kvm_vcpu *vcpu) static inline int kvmppc_ld32(struct kvm_vcpu *vcpu, ulong *eaddr, u32 *ptr, bool data) { - return kvmppc_ld(vcpu, eaddr, sizeof(u32), ptr, data); + int ret; + + ret = kvmppc_ld(vcpu, eaddr, sizeof(u32), ptr, data); + + if (kvmppc_need_byteswap(vcpu)) + *ptr = swab32(*ptr); + + return ret; } static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index b15554a..3769a13 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -53,13 +53,13 @@ extern void kvmppc_handler_highmem(void); extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu); extern int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, - unsigned int rt, unsigned int bytes, - int is_bigendian); + unsigned int rt, unsigned int bytes, + int not_reverse); extern int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu, - unsigned int rt, unsigned int bytes, - int is_bigendian); + unsigned int rt, unsigned int bytes, + int not_reverse); extern int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, - u64 val, unsigned int bytes, int is_bigendian); + u64 val, unsigned int bytes, int not_reverse); extern int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu); diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 77f1baa..89d4fbe 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1404,10 +1404,19 @@ fast_interrupt_c_return: lwz r8, 0(r10) mtmsrd r3 + andi. r0, r11, MSR_LE + /* Store the result */ stw r8, VCPU_LAST_INST(r9) + beq after_inst_store + + /* Swap and store the result */ + addi r4, r9, VCPU_LAST_INST + stwbrx r8, 0, r4 + /* Unset guest mode. */ +after_inst_store: li r0, KVM_GUEST_MODE_HOST_HV stb r0, HSTATE_IN_GUEST(r13) b guest_exit_cont diff --git a/arch/powerpc/kvm/book3s_segment.S b/arch/powerpc/kvm/book3s_segment.S index 1abe478..a942390 100644 --- a/arch/powerpc/kvm/book3s_segment.S +++ b/arch/powerpc/kvm/book3s_segment.S @@ -289,6 +289,15 @@ ld_last_inst: #endif stw r0, SVCPU_LAST_INST(r13) +#ifdef CONFIG_PPC64 + andi. r9, r4, MSR_LE + beq no_ld_last_inst + + /* swap and store the result */ + addi r9, r13, SVCPU_LAST_INST + stwbrx r0, 0, r9 +#endif + no_ld_last_inst: /* Unset guest mode */ diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index 751cd45..5e38004 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -219,7 +219,6 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) * lmw * stmw * - * XXX is_bigendian should depend on MMU mapping or MSR[LE] */ /* XXX Should probably auto-generate instruction decoding for a particular core * from opcode tables in the future. */ diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 07c0106..6950f2b 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -625,9 +625,13 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, } int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, - unsigned int rt, unsigned int bytes, int is_bigendian) + unsigned int rt, unsigned int bytes, int not_reverse) { int idx, ret; + int is_bigendian = not_reverse; + + if (!kvmppc_is_bigendian(vcpu)) + is_bigendian = !not_reverse; if (bytes > sizeof(run->mmio.data)) { printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__, @@ -662,21 +666,25 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, /* Same as above, but sign extends */ int kvmppc_handle_loads(struct kvm_run *run, struct kvm_vcpu *vcpu, - unsigned int rt, unsigned int bytes, int is_bigendian) + unsigned int rt, unsigned int bytes, int not_reverse) { int r; vcpu->arch.mmio_sign_extend = 1; - r = kvmppc_handle_load(run, vcpu, rt, bytes, is_bigendian); + r = kvmppc_handle_load(run, vcpu, rt, bytes, not_reverse); return r; } int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, - u64 val, unsigned int bytes, int is_bigendian) + u64 val, unsigned int bytes, int not_reverse) { void *data = run->mmio.data; int idx, ret; + int is_bigendian = not_reverse; + + if (!kvmppc_is_bigendian(vcpu)) + is_bigendian = !not_reverse; if (bytes > sizeof(run->mmio.data)) { printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,