Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753716Ab3FNUIk (ORCPT ); Fri, 14 Jun 2013 16:08:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:2453 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753359Ab3FNUIj (ORCPT ); Fri, 14 Jun 2013 16:08:39 -0400 Date: Fri, 14 Jun 2013 16:08:08 -0400 From: Vivek Goyal To: Michael Holzheu Cc: HATAYAMA Daisuke , Jan Willeke , Martin Schwidefsky , Heiko Carstens , linux-kernel@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH v5 4/5] s390/vmcore: Implement remap_oldmem_pfn_range for s390 Message-ID: <20130614200808.GO12023@redhat.com> References: <1370624161-2298-1-git-send-email-holzheu@linux.vnet.ibm.com> <1370624161-2298-5-git-send-email-holzheu@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1370624161-2298-5-git-send-email-holzheu@linux.vnet.ibm.com> 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: 2208 Lines: 68 On Fri, Jun 07, 2013 at 06:56:00PM +0200, Michael Holzheu wrote: > From: Jan Willeke > > This patch introduces the s390 specific way to map pages from oldmem. > The memory area below OLDMEM_SIZE is mapped with offset OLDMEM_BASE. > The other old memory is mapped directly. > If we get rid of swap logic in copy_oldmem_page(), quite some amount of code can be cleaned up. One has to spcial case only zfcpdump to read from HSA memory. Anyway sounds like a s390 specific cleanup in a separate series. Thanks Vivek > Signed-off-by: Jan Willeke > Signed-off-by: Michael Holzheu > --- > arch/s390/kernel/crash_dump.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c > index a17f8d4..12ccc3c 100644 > --- a/arch/s390/kernel/crash_dump.c > +++ b/arch/s390/kernel/crash_dump.c > @@ -56,6 +56,32 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, > } > > /* > + * Remap "oldmem" > + * > + * For the kdump reserved memory this functions performs a swap operation: > + * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] > + */ > +int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from, > + unsigned long pfn, unsigned long size, pgprot_t prot) > +{ > + unsigned long size_old; > + int rc; > + > + if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) { > + size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT)); > + rc = remap_pfn_range(vma, from, > + pfn + (OLDMEM_BASE >> PAGE_SHIFT), > + size_old, prot); > + if (rc || size == size_old) > + return rc; > + size -= size_old; > + from += size_old; > + pfn += size_old >> PAGE_SHIFT; > + } > + return remap_pfn_range(vma, from, pfn, size, prot); > +} > + > +/* > * Copy memory from old kernel > */ > int copy_from_oldmem(void *dest, void *src, size_t count) > -- > 1.8.1.6 -- 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/