Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934587AbaGXTcd (ORCPT ); Thu, 24 Jul 2014 15:32:33 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:58166 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934157AbaGXTcc (ORCPT ); Thu, 24 Jul 2014 15:32:32 -0400 Date: Thu, 24 Jul 2014 19:32:25 +0000 From: Serge Hallyn To: Cyrill Gorcunov Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, keescook@chromium.org, tj@kernel.org, akpm@linux-foundation.org, avagin@openvz.org, ebiederm@xmission.com, hpa@zytor.com, serge.hallyn@canonical.com, xemul@parallels.com, segoon@openwall.com, kamezawa.hiroyu@jp.fujitsu.com, mtk.manpages@gmail.com, jln@google.com Subject: Re: [rfc 1/4] mm: Introduce may_adjust_brk helper Message-ID: <20140724193225.GT26600@ubuntumail> References: <20140724164657.452106845@openvz.org> <20140724165047.437075575@openvz.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140724165047.437075575@openvz.org> 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 Quoting Cyrill Gorcunov (gorcunov@openvz.org): > To eliminate code duplication lets introduce may_adjust_brk > helper which we will use in brk() and prctl() syscalls. > > Signed-off-by: Cyrill Gorcunov > Cc: Kees Cook > Cc: Tejun Heo > Cc: Andrew Morton > Cc: Andrew Vagin > Cc: Eric W. Biederman > Cc: H. Peter Anvin > Cc: Serge Hallyn > Cc: Pavel Emelyanov > Cc: Vasiliy Kulikov > Cc: KAMEZAWA Hiroyuki > Cc: Michael Kerrisk > Cc: Julien Tinnes > --- > include/linux/mm.h | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > > Index: linux-2.6.git/include/linux/mm.h > =================================================================== > --- linux-2.6.git.orig/include/linux/mm.h > +++ linux-2.6.git/include/linux/mm.h > @@ -18,6 +18,7 @@ > #include > #include > #include > +#include > > struct mempolicy; > struct anon_vma; > @@ -1780,6 +1781,19 @@ extern struct vm_area_struct *copy_vma(s > bool *need_rmap_locks); > extern void exit_mmap(struct mm_struct *); > > +static inline int may_adjust_brk(unsigned long rlim, > + unsigned long new_brk, > + unsigned long start_brk, > + unsigned long end_data, > + unsigned long start_data) > +{ > + if (rlim < RLIMIT_DATA) { In the code you're replacing, this was RLIM_INFINITY. Did you really mean for this to be RLIMIT_DATA, aka 2? > + if (((new_brk - start_brk) + (end_data - start_data)) > rlim) > + return -ENOSPC; > + } > + return 0; > +} > + > extern int mm_take_all_locks(struct mm_struct *mm); > extern void mm_drop_all_locks(struct mm_struct *mm); > > -- 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/