From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peng Fan Subject: [PATCH 2/2] arm:kvm remove len 8 for mmio read write buf Date: Mon, 22 Dec 2014 19:23:19 +0800 Message-ID: <1419247399-26113-2-git-send-email-van.freenix@gmail.com> References: <1419247399-26113-1-git-send-email-van.freenix@gmail.com> Cc: gleb@kernel.org, pbonzini@redhat.com, linux@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, van.freenix@gmail.com To: christoffer.dall@linaro.org, marc.zyngier@arm.com Return-path: In-Reply-To: <1419247399-26113-1-git-send-email-van.freenix@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org For arm 32 bit architecture, 8 bytes load/store operation in one instruction will not be generated by compiler. And before invoke mmio_read_buf, there is a piece of code: " len = run->mmio.len; if (len > sizeof(unsigned long)) return -EINVAL; data = mmio_read_buf(run->mmio.data, len); " This piece code also tells that len variable does not exceeds 4 bytes. So, remove 8 bytes assign in mmio_read_buf and mmio_write_buf. Signed-off-by: Peng Fan CC: Gleb Natapov CC: Paolo Bonzini CC: Christoffer Dall CC: Marc Zyngier CC: Russell King --- arch/arm/kvm/mmio.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c index 4cb5a93..953a819 100644 --- a/arch/arm/kvm/mmio.c +++ b/arch/arm/kvm/mmio.c @@ -30,7 +30,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) u8 byte; u16 hword; u32 word; - u64 dword; } tmp; switch (len) { @@ -46,10 +45,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data) tmp.word = data; datap = &tmp.word; break; - case 8: - tmp.dword = data; - datap = &tmp.dword; - break; } memcpy(buf, datap, len); @@ -61,7 +56,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) union { u16 hword; u32 word; - u64 dword; } tmp; switch (len) { @@ -76,10 +70,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len) memcpy(&tmp.word, buf, len); data = tmp.word; break; - case 8: - memcpy(&tmp.dword, buf, len); - data = tmp.dword; - break; } return data; -- 1.8.4