From patchwork Wed Sep 17 23:00:05 2008 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kumar Gala X-Patchwork-Id: 470 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id 6E22BDE912 for ; Thu, 18 Sep 2008 09:01:11 +1000 (EST) X-Original-To: linuxppc-dev@ozlabs.org Delivered-To: linuxppc-dev@ozlabs.org Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2BD09DDF23 for ; Thu, 18 Sep 2008 09:00:12 +1000 (EST) Received: from localhost (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id m8HN09C7005660 for ; Wed, 17 Sep 2008 18:00:09 -0500 From: Kumar Gala To: linuxppc-dev@ozlabs.org Subject: [PATCH v7 4/4] powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 32-bit Date: Wed, 17 Sep 2008 18:00:05 -0500 Message-Id: <1221692405-19880-4-git-send-email-galak@kernel.crashing.org> X-Mailer: git-send-email 1.5.5.1 In-Reply-To: <1221692405-19880-3-git-send-email-galak@kernel.crashing.org> References: <1221692405-19880-1-git-send-email-galak@kernel.crashing.org> <1221692405-19880-2-git-send-email-galak@kernel.crashing.org> <1221692405-19880-3-git-send-email-galak@kernel.crashing.org> X-BeenThere: linuxppc-dev@ozlabs.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@ozlabs.org Implement _PAGE_SPECIAL and pte_special() for 32-bit powerpc. This bit will be used by the fast get_user_pages() to differenciate PTEs that correspond to a valid struct page from special mappings that don't such as IO mappings obtained via io_remap_pfn_ranges(). We currently only implement this on sub-arch that support SMP or will so in the future (6xx, 44x, FSL-BookE) and not (8xx, 40x). Signed-off-by: Kumar Gala Acked-by: Benjamin Herrenschmidt diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index d1d23b9..e8f31a5 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -261,6 +261,7 @@ extern int icache_44x_need_flush; #define _PAGE_HWEXEC 0x00000004 /* H: Execute permission */ #define _PAGE_ACCESSED 0x00000008 /* S: Page referenced */ #define _PAGE_DIRTY 0x00000010 /* S: Page dirty */ +#define _PAGE_SPECIAL 0x00000020 /* S: Special page */ #define _PAGE_USER 0x00000040 /* S: User page */ #define _PAGE_ENDIAN 0x00000080 /* H: E bit */ #define _PAGE_GUARDED 0x00000100 /* H: G bit */ @@ -276,6 +277,7 @@ extern int icache_44x_need_flush; /* ERPN in a PTE never gets cleared, ignore it */ #define _PTE_NONE_MASK 0xffffffff00000000ULL +#define __HAVE_ARCH_PTE_SPECIAL #elif defined(CONFIG_FSL_BOOKE) /* @@ -305,6 +307,7 @@ extern int icache_44x_need_flush; #define _PAGE_COHERENT 0x00100 /* H: M bit */ #define _PAGE_NO_CACHE 0x00200 /* H: I bit */ #define _PAGE_WRITETHRU 0x00400 /* H: W bit */ +#define _PAGE_SPECIAL 0x00800 /* S: Special page */ #ifdef CONFIG_PTE_64BIT /* ERPN in a PTE never gets cleared, ignore it */ @@ -315,6 +318,8 @@ extern int icache_44x_need_flush; #define _PMD_PRESENT_MASK (PAGE_MASK) #define _PMD_BAD (~PAGE_MASK) +#define __HAVE_ARCH_PTE_SPECIAL + #elif defined(CONFIG_8xx) /* Definitions for 8xx embedded chips. */ #define _PAGE_PRESENT 0x0001 /* Page is valid */ @@ -362,6 +367,7 @@ extern int icache_44x_need_flush; #define _PAGE_ACCESSED 0x100 /* R: page referenced */ #define _PAGE_EXEC 0x200 /* software: i-cache coherency required */ #define _PAGE_RW 0x400 /* software: user write access allowed */ +#define _PAGE_SPECIAL 0x800 /* software: Special page */ #define _PTE_NONE_MASK _PAGE_HASHPTE @@ -372,6 +378,8 @@ extern int icache_44x_need_flush; /* Hash table based platforms need atomic updates of the linux PTE */ #define PTE_ATOMIC_UPDATES 1 +#define __HAVE_ARCH_PTE_SPECIAL + #endif /* @@ -404,6 +412,9 @@ extern int icache_44x_need_flush; #ifndef _PAGE_WRITETHRU #define _PAGE_WRITETHRU 0 #endif +#ifndef _PAGE_SPECIAL +#define _PAGE_SPECIAL 0 +#endif #ifndef _PMD_PRESENT_MASK #define _PMD_PRESENT_MASK _PMD_PRESENT #endif @@ -534,7 +545,7 @@ static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; } static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; } -static inline int pte_special(pte_t pte) { return 0; } +static inline int pte_special(pte_t pte) { return pte_val(pte) & _PAGE_SPECIAL; } static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; } static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; } @@ -553,7 +564,7 @@ static inline pte_t pte_mkdirty(pte_t pte) { static inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= _PAGE_ACCESSED; return pte; } static inline pte_t pte_mkspecial(pte_t pte) { - return pte; } + pte_val(pte) |= _PAGE_SPECIAL; return pte; } static inline unsigned long pte_pgprot(pte_t pte) { return __pgprot(pte_val(pte)) & PAGE_PROT_BITS;