Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757019Ab3CYKc7 (ORCPT ); Mon, 25 Mar 2013 06:32:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42697 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756991Ab3CYKc6 (ORCPT ); Mon, 25 Mar 2013 06:32:58 -0400 Date: Mon, 25 Mar 2013 11:31:05 +0100 From: Anton Arapov To: Oleg Nesterov Cc: Srikar Dronamraju , LKML , Josh Stone , Frank Eigler , Peter Zijlstra , Ingo Molnar , Ananth N Mavinakayanahalli , adrian.m.negreanu@intel.com, Torsten.Polle@gmx.de Subject: Re: [PATCH 2/5] uprobes: Change __copy_insn() to use copy_from_page() Message-ID: <20130325103105.GC8163@bandura.brq.redhat.com> References: <20130324182040.GA13078@redhat.com> <20130324182115.GA13308@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130324182115.GA13308@redhat.com> X-PGP-Key: http://people.redhat.com/aarapov/gpg User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1646 Lines: 54 On Sun, Mar 24, 2013 at 07:21:15PM +0100, Oleg Nesterov wrote: > Change __copy_insn() to use copy_from_page() and simplify the code. > > Signed-off-by: Oleg Nesterov > --- > kernel/events/uprobes.c | 13 ++----------- > 1 files changed, 2 insertions(+), 11 deletions(-) > > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c > index d6891cb..0a759c6 100644 > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -477,30 +477,21 @@ __copy_insn(struct address_space *mapping, struct file *filp, char *insn, > unsigned long nbytes, loff_t offset) > { > struct page *page; > - void *vaddr; > - unsigned long off; > - pgoff_t idx; > > if (!filp) > return -EINVAL; > > if (!mapping->a_ops->readpage) > return -EIO; > - > - idx = offset >> PAGE_CACHE_SHIFT; > - off = offset & ~PAGE_MASK; > - > /* > * Ensure that the page that has the original instruction is > * populated and in page-cache. > */ > - page = read_mapping_page(mapping, idx, filp); > + page = read_mapping_page(mapping, offset >> PAGE_CACHE_SHIFT, filp); > if (IS_ERR(page)) > return PTR_ERR(page); > > - vaddr = kmap_atomic(page); > - memcpy(insn, vaddr + off, nbytes); > - kunmap_atomic(vaddr); > + copy_from_page(page, offset, insn, nbytes); > page_cache_release(page); > > return 0; > -- > 1.5.5.1 > Acked-by: Anton Arapov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/