Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752379AbbG2JUV (ORCPT ); Wed, 29 Jul 2015 05:20:21 -0400 Received: from mx2.suse.de ([195.135.220.15]:33935 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751082AbbG2JUS (ORCPT ); Wed, 29 Jul 2015 05:20:18 -0400 Subject: Re: [Patch V6 12/16] mm: provide early_memremap_ro to establish read-only mapping To: linux-kernel@vger.kernel.org, Arnd Bergmann , linux-mm@kvack.org, linux-arch@vger.kernel.org References: <1437108697-4115-1-git-send-email-jgross@suse.com> <1437108697-4115-13-git-send-email-jgross@suse.com> <55ADCF40.6010903@suse.com> Cc: xen-devel@lists.xensource.com, konrad.wilk@oracle.com, david.vrabel@citrix.com, boris.ostrovsky@oracle.com From: Juergen Gross Message-ID: <55B89ACD.2070903@suse.com> Date: Wed, 29 Jul 2015 11:20:13 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <55ADCF40.6010903@suse.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3780 Lines: 109 On 07/21/2015 06:49 AM, Juergen Gross wrote: > Hi MM maintainers, > > this patch is the last requiring an ack for the series to go in. > Could you please comment? PING? > > > Juergen > > On 07/17/2015 06:51 AM, Juergen Gross wrote: >> During early boot as Xen pv domain the kernel needs to map some page >> tables supplied by the hypervisor read only. This is needed to be >> able to relocate some data structures conflicting with the physical >> memory map especially on systems with huge RAM (above 512GB). >> >> Provide the function early_memremap_ro() to provide this read only >> mapping. >> >> Signed-off-by: Juergen Gross >> Acked-by: Konrad Rzeszutek Wilk >> Cc: Arnd Bergmann >> Cc: linux-mm@kvack.org >> Cc: linux-arch@vger.kernel.org >> --- >> include/asm-generic/early_ioremap.h | 2 ++ >> include/asm-generic/fixmap.h | 3 +++ >> mm/early_ioremap.c | 12 ++++++++++++ >> 3 files changed, 17 insertions(+) >> >> diff --git a/include/asm-generic/early_ioremap.h >> b/include/asm-generic/early_ioremap.h >> index a5de55c..316bd04 100644 >> --- a/include/asm-generic/early_ioremap.h >> +++ b/include/asm-generic/early_ioremap.h >> @@ -11,6 +11,8 @@ extern void __iomem *early_ioremap(resource_size_t >> phys_addr, >> unsigned long size); >> extern void *early_memremap(resource_size_t phys_addr, >> unsigned long size); >> +extern void *early_memremap_ro(resource_size_t phys_addr, >> + unsigned long size); >> extern void early_iounmap(void __iomem *addr, unsigned long size); >> extern void early_memunmap(void *addr, unsigned long size); >> >> diff --git a/include/asm-generic/fixmap.h b/include/asm-generic/fixmap.h >> index f23174f..1cbb833 100644 >> --- a/include/asm-generic/fixmap.h >> +++ b/include/asm-generic/fixmap.h >> @@ -46,6 +46,9 @@ static inline unsigned long virt_to_fix(const >> unsigned long vaddr) >> #ifndef FIXMAP_PAGE_NORMAL >> #define FIXMAP_PAGE_NORMAL PAGE_KERNEL >> #endif >> +#if !defined(FIXMAP_PAGE_RO) && defined(PAGE_KERNEL_RO) >> +#define FIXMAP_PAGE_RO PAGE_KERNEL_RO >> +#endif >> #ifndef FIXMAP_PAGE_NOCACHE >> #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NOCACHE >> #endif >> diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c >> index e10ccd2..0cfadaf 100644 >> --- a/mm/early_ioremap.c >> +++ b/mm/early_ioremap.c >> @@ -217,6 +217,13 @@ early_memremap(resource_size_t phys_addr, >> unsigned long size) >> return (__force void *)__early_ioremap(phys_addr, size, >> FIXMAP_PAGE_NORMAL); >> } >> +#ifdef FIXMAP_PAGE_RO >> +void __init * >> +early_memremap_ro(resource_size_t phys_addr, unsigned long size) >> +{ >> + return (__force void *)__early_ioremap(phys_addr, size, >> FIXMAP_PAGE_RO); >> +} >> +#endif >> #else /* CONFIG_MMU */ >> >> void __init __iomem * >> @@ -231,6 +238,11 @@ early_memremap(resource_size_t phys_addr, >> unsigned long size) >> { >> return (void *)phys_addr; >> } >> +void __init * >> +early_memremap_ro(resource_size_t phys_addr, unsigned long size) >> +{ >> + return (void *)phys_addr; >> +} >> >> void __init early_iounmap(void __iomem *addr, unsigned long size) >> { >> > > -- > 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/ > -- 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/