From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from NAM01-SN1-obe.outbound.protection.outlook.com (mail-sn1nam01on0086.outbound.protection.outlook.com [104.47.32.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xGWBB4zzkzDrJv for ; Tue, 25 Jul 2017 05:08:50 +1000 (AEST) From: Brijesh Singh To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-efi@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , "H . Peter Anvin" , Borislav Petkov , Andy Lutomirski , Tony Luck , Piotr Luc , Tom Lendacky , Fenghua Yu , Lu Baolu , Reza Arbab , David Howells , Matt Fleming , "Kirill A . Shutemov" , Laura Abbott , Ard Biesheuvel , Andrew Morton , Eric Biederman , Benjamin Herrenschmidt , Paul Mackerras , Konrad Rzeszutek Wilk , Jonathan Corbet , Dave Airlie , Kees Cook , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Arnd Bergmann , Tejun Heo , Christoph Lameter , Brijesh Singh Subject: [RFC Part1 PATCH v3 13/17] x86/io: Unroll string I/O when SEV is active Date: Mon, 24 Jul 2017 14:07:53 -0500 Message-Id: <20170724190757.11278-14-brijesh.singh@amd.com> In-Reply-To: <20170724190757.11278-1-brijesh.singh@amd.com> References: <20170724190757.11278-1-brijesh.singh@amd.com> MIME-Version: 1.0 Content-Type: text/plain List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Tom Lendacky Secure Encrypted Virtualization (SEV) does not support string I/O, so unroll the string I/O operation into a loop operating on one element at a time. Signed-off-by: Tom Lendacky Signed-off-by: Brijesh Singh --- arch/x86/include/asm/io.h | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index e080a39..2f3c002 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -327,14 +327,32 @@ static inline unsigned type in##bwl##_p(int port) \ \ static inline void outs##bwl(int port, const void *addr, unsigned long count) \ { \ - asm volatile("rep; outs" #bwl \ - : "+S"(addr), "+c"(count) : "d"(port)); \ + if (sev_active()) { \ + unsigned type *value = (unsigned type *)addr; \ + while (count) { \ + out##bwl(*value, port); \ + value++; \ + count--; \ + } \ + } else { \ + asm volatile("rep; outs" #bwl \ + : "+S"(addr), "+c"(count) : "d"(port)); \ + } \ } \ \ static inline void ins##bwl(int port, void *addr, unsigned long count) \ { \ - asm volatile("rep; ins" #bwl \ - : "+D"(addr), "+c"(count) : "d"(port)); \ + if (sev_active()) { \ + unsigned type *value = (unsigned type *)addr; \ + while (count) { \ + *value = in##bwl(port); \ + value++; \ + count--; \ + } \ + } else { \ + asm volatile("rep; ins" #bwl \ + : "+D"(addr), "+c"(count) : "d"(port)); \ + } \ } BUILDIO(b, b, char) -- 2.9.4