From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932156Ab0EDNDk (ORCPT ); Tue, 4 May 2010 09:03:40 -0400 Received: from mail-pw0-f46.google.com ([209.85.160.46]:58456 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932122Ab0EDNDf (ORCPT ); Tue, 4 May 2010 09:03:35 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:in-reply-to:references:x-mailer :mime-version:content-type:content-transfer-encoding; b=VB45w/Jr9C3KrrrjxD0r99qIeiec0KezJU1Xy90bJu72A+ytzhPXqbeyMpNTjnfoVS +RZY+Lux6yTM2y1QYDQK9s5FJ8MJxXLLo9o4YzYoPTlIyHa7oZNQqY0H145soUUyqHie BsC+iB/zYZ1eGUjbuE/SEl/8H6fuTVWmv6NFk= Date: Tue, 4 May 2010 22:03:33 +0900 From: Takuya Yoshikawa To: Takuya Yoshikawa Cc: avi@redhat.com, mtosatti@redhat.com, agraf@suse.de, yoshikawa.takuya@oss.ntt.co.jp, fernando@oss.ntt.co.jp, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm-ia64@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, benh@kernel.crashing.org, paulus@samba.org, linuxppc-dev@ozlabs.org, arnd@arndb.de, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC][PATCH 6/12 not tested yet] PPC: introduce copy_in_user() for 32-bit Message-Id: <20100504220333.61e44128.takuya.yoshikawa@gmail.com> In-Reply-To: <20100504215645.6448af8f.takuya.yoshikawa@gmail.com> References: <20100504215645.6448af8f.takuya.yoshikawa@gmail.com> X-Mailer: Sylpheed 3.0.2 (GTK+ 2.20.0; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org During the work of KVM's dirty page logging optimization, we encountered the need of copy_in_user() for 32-bit ppc and x86: these will be used for manipulating dirty bitmaps in user space. So we implement copy_in_user() for 32-bit with __copy_tofrom_user(). Signed-off-by: Takuya Yoshikawa Signed-off-by: Fernando Luis Vazquez Cao CC: Alexander Graf CC: Benjamin Herrenschmidt CC: Paul Mackerras --- arch/powerpc/include/asm/uaccess.h | 17 +++++++++++++++++ 1 files changed, 17 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h index bd0fb84..3a01ce8 100644 --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -359,6 +359,23 @@ static inline unsigned long copy_to_user(void __user *to, return n; } +static inline unsigned long copy_in_user(void __user *to, + const void __user *from, unsigned long n) +{ + unsigned long over; + + if (likely(access_ok(VERIFY_READ, from, n) && + access_ok(VERIFY_WRITE, to, n))) + return __copy_tofrom_user(to, from, n); + if (((unsigned long)from < TASK_SIZE) || + ((unsigned long)to < TASK_SIZE)) { + over = max((unsigned long)from, (unsigned long)to) + + n - TASK_SIZE; + return __copy_tofrom_user(to, from, n - over) + over; + } + return n; +} + #else /* __powerpc64__ */ #define __copy_in_user(to, from, size) \ -- 1.7.0.4