From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id AF4236B0047 for ; Sun, 17 Jan 2010 10:43:52 -0500 (EST) Date: Sun, 17 Jan 2010 10:43:43 -0500 From: Christoph Hellwig Subject: Re: [PATCH v3 06/12] Add get_user_pages() variant that fails if major fault is required. Message-ID: <20100117154343.GA27123@infradead.org> References: <1262700774-1808-1-git-send-email-gleb@redhat.com> <1262700774-1808-7-git-send-email-gleb@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1262700774-1808-7-git-send-email-gleb@redhat.com> Sender: owner-linux-mm@kvack.org To: Gleb Natapov Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, avi@redhat.com, mingo@elte.hu, a.p.zijlstra@chello.nl, tglx@linutronix.de, hpa@zytor.com, riel@redhat.com, cl@linux-foundation.org List-ID: On Tue, Jan 05, 2010 at 04:12:48PM +0200, Gleb Natapov wrote: > This patch add get_user_pages() variant that only succeeds if getting > a reference to a page doesn't require major fault. > > +int get_user_pages_noio(struct task_struct *tsk, struct mm_struct *mm, > + unsigned long start, int nr_pages, int write, int force, > + struct page **pages, struct vm_area_struct **vmas) > +{ > + int flags = FOLL_TOUCH | FOLL_MINOR; > + > + if (pages) > + flags |= FOLL_GET; > + if (write) > + flags |= FOLL_WRITE; > + if (force) > + flags |= FOLL_FORCE; > + > + return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas); Wouldn't it be better to just export __get_user_pages as a proper user interface, maybe replacing get_user_pages by it entirely? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org