Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753954AbbDML7e (ORCPT ); Mon, 13 Apr 2015 07:59:34 -0400 Received: from mta-out1.inet.fi ([62.71.2.227]:43317 "EHLO kirsi1.inet.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752193AbbDML7b (ORCPT ); Mon, 13 Apr 2015 07:59:31 -0400 Date: Mon, 13 Apr 2015 14:58:11 +0300 From: "Kirill A. Shutemov" To: Laurent Dufour Cc: Andrew Morton , "Kirill A. Shutemov" , Hugh Dickins , Rik van Riel , Mel Gorman , Pavel Emelyanov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Ingo Molnar , linuxppc-dev@lists.ozlabs.org, cov@codeaurora.org, criu@openvz.org Subject: Re: [RESEND PATCH v3 1/2] mm: Introducing arch_remap hook Message-ID: <20150413115811.GA12354@node.dhcp.inet.fi> References: <9d827fc618a718830b2c47aa87e8be546914c897.1428916945.git.ldufour@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9d827fc618a718830b2c47aa87e8be546914c897.1428916945.git.ldufour@linux.vnet.ibm.com> User-Agent: Mutt/1.5.23.1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2725 Lines: 83 On Mon, Apr 13, 2015 at 11:56:27AM +0200, Laurent Dufour wrote: > Some architecture would like to be triggered when a memory area is moved > through the mremap system call. > > This patch is introducing a new arch_remap mm hook which is placed in the > path of mremap, and is called before the old area is unmapped (and the > arch_unmap hook is called). > > The architectures which need to call this hook should define > __HAVE_ARCH_REMAP in their asm/mmu_context.h and provide the arch_remap > service with the following prototype: > void arch_remap(struct mm_struct *mm, > unsigned long old_start, unsigned long old_end, > unsigned long new_start, unsigned long new_end); > > Signed-off-by: Laurent Dufour > Reviewed-by: Ingo Molnar > --- > mm/mremap.c | 19 +++++++++++++------ > 1 file changed, 13 insertions(+), 6 deletions(-) > > diff --git a/mm/mremap.c b/mm/mremap.c > index 2dc44b1cb1df..009db5565893 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -25,6 +25,7 @@ > > #include > #include > +#include > > #include "internal.h" > > @@ -286,13 +287,19 @@ static unsigned long move_vma(struct vm_area_struct *vma, > old_len = new_len; > old_addr = new_addr; > new_addr = -ENOMEM; > - } else if (vma->vm_file && vma->vm_file->f_op->mremap) { > - err = vma->vm_file->f_op->mremap(vma->vm_file, new_vma); > - if (err < 0) { > - move_page_tables(new_vma, new_addr, vma, old_addr, > - moved_len, true); > - return err; > + } else { > + if (vma->vm_file && vma->vm_file->f_op->mremap) { > + err = vma->vm_file->f_op->mremap(vma->vm_file, new_vma); > + if (err < 0) { > + move_page_tables(new_vma, new_addr, vma, > + old_addr, moved_len, true); > + return err; > + } > } > +#ifdef __HAVE_ARCH_REMAP It would be cleaner to provide dummy arch_remap() for !__HAVE_ARCH_REMAP in some generic header. > + arch_remap(mm, old_addr, old_addr+old_len, > + new_addr, new_addr+new_len); Spaces around '+'? > +#endif > } > > /* Conceal VM_ACCOUNT so old reservation is not undone */ > -- > 1.9.1 > > -- > 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/ -- Kirill A. Shutemov -- 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/