From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f53.google.com (mail-pa0-f53.google.com [209.85.220.53]) by kanga.kvack.org (Postfix) with ESMTP id 08A4F6B0011 for ; Mon, 21 Dec 2015 00:45:31 -0500 (EST) Received: by mail-pa0-f53.google.com with SMTP id cy9so11772895pac.0 for ; Sun, 20 Dec 2015 21:45:31 -0800 (PST) Received: from mga04.intel.com (mga04.intel.com. [192.55.52.120]) by mx.google.com with ESMTP id xd1si1345865pab.130.2015.12.20.21.45.27 for ; Sun, 20 Dec 2015 21:45:27 -0800 (PST) Subject: [-mm PATCH v4 10/18] x86, mm: introduce _PAGE_DEVMAP From: Dan Williams Date: Sun, 20 Dec 2015 21:45:00 -0800 Message-ID: <20151221054500.34542.62760.stgit@dwillia2-desk3.jf.intel.com> In-Reply-To: <20151221054406.34542.64393.stgit@dwillia2-desk3.jf.intel.com> References: <20151221054406.34542.64393.stgit@dwillia2-desk3.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org Cc: linux-nvdimm@lists.01.org, x86@kernel.org, linux-mm@kvack.org, Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner _PAGE_DEVMAP is a hardware-unused pte bit that will later be used in the get_user_pages() path to identify pfns backed by the dynamic allocation established by devm_memremap_pages. Upon seeing that bit the gup path will lookup and pin the allocation while the pages are in use. Since the _PAGE_DEVMAP bit is > 32 it must be cast to u64 instead of a pteval_t to allow pmd_flags() usage in the realmode boot code to build. Cc: x86@kernel.org Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Dan Williams --- arch/x86/include/asm/pgtable_types.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index d1b76f88ccd1..04c27a013165 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -24,7 +24,9 @@ #define _PAGE_BIT_CPA_TEST _PAGE_BIT_SOFTW1 #define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */ #define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */ -#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ +#define _PAGE_BIT_SOFTW4 58 /* available for programmer */ +#define _PAGE_BIT_DEVMAP _PAGE_BIT_SOFTW4 +#define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ /* If _PAGE_BIT_PRESENT is clear, we use these: */ /* - if the user mapped it with PROT_NONE; pte_present gives true */ @@ -83,8 +85,11 @@ #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) #define _PAGE_NX (_AT(pteval_t, 1) << _PAGE_BIT_NX) +#define _PAGE_DEVMAP (_AT(u64, 1) << _PAGE_BIT_DEVMAP) +#define __HAVE_ARCH_PTE_DEVMAP #else #define _PAGE_NX (_AT(pteval_t, 0)) +#define _PAGE_DEVMAP (_AT(pteval_t, 0)) #endif #define _PAGE_PROTNONE (_AT(pteval_t, 1) << _PAGE_BIT_PROTNONE) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org