Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754273AbbDZOII (ORCPT ); Sun, 26 Apr 2015 10:08:08 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:40956 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754115AbbDZODp (ORCPT ); Sun, 26 Apr 2015 10:03:45 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Steve Capper , Will Deacon , Russell King , Hou Pengyang Subject: [PATCH 3.14 37/42] ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear Date: Sun, 26 Apr 2015 16:01:56 +0200 Message-Id: <20150426134249.780674190@linuxfoundation.org> X-Mailer: git-send-email 2.3.6 In-Reply-To: <20150426134248.160161895@linuxfoundation.org> References: <20150426134248.160161895@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3937 Lines: 96 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Steven Capper commit f2950706871c4b6e8c0f0d7c3f62d35930b8de63 upstream. Long descriptors on ARM are 64 bits, and some pte functions such as pte_dirty return a bitwise-and of a flag with the pte value. If the flag to be tested resides in the upper 32 bits of the pte, then we run into the danger of the result being dropped if downcast. For example: gather_stats(page, md, pte_dirty(*pte), 1); where pte_dirty(*pte) is downcast to an int. This patch introduces a new macro pte_isset which performs the bitwise and, then performs a double logical invert (where needed) to ensure predictable downcasting. The logical inverse pte_isclear is also introduced. Equivalent pmd functions for Transparent HugePages have also been added. Signed-off-by: Steve Capper Reviewed-by: Will Deacon Signed-off-by: Russell King [hpy: Backported to 3.14 - adjust the context ] Signed-off-by: Hou Pengyang Signed-off-by: Greg Kroah-Hartman --- arch/arm/include/asm/pgtable-3level.h | 12 ++++++++---- arch/arm/include/asm/pgtable.h | 14 +++++++++----- 2 files changed, 17 insertions(+), 9 deletions(-) --- a/arch/arm/include/asm/pgtable-3level.h +++ b/arch/arm/include/asm/pgtable-3level.h @@ -207,17 +207,21 @@ static inline pmd_t *pmd_offset(pud_t *p #define pte_huge(pte) (pte_val(pte) && !(pte_val(pte) & PTE_TABLE_BIT)) #define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT)) -#define pmd_young(pmd) (pmd_val(pmd) & PMD_SECT_AF) +#define pmd_isset(pmd, val) ((u32)(val) == (val) ? pmd_val(pmd) & (val) \ + : !!(pmd_val(pmd) & (val))) +#define pmd_isclear(pmd, val) (!(pmd_val(pmd) & (val))) + +#define pmd_young(pmd) (pmd_isset((pmd), PMD_SECT_AF)) #define __HAVE_ARCH_PMD_WRITE -#define pmd_write(pmd) (!(pmd_val(pmd) & PMD_SECT_RDONLY)) +#define pmd_write(pmd) (pmd_isclear((pmd), PMD_SECT_RDONLY)) #define pmd_hugewillfault(pmd) (!pmd_young(pmd) || !pmd_write(pmd)) #define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd)) #ifdef CONFIG_TRANSPARENT_HUGEPAGE -#define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT)) -#define pmd_trans_splitting(pmd) (pmd_val(pmd) & PMD_SECT_SPLITTING) +#define pmd_trans_huge(pmd) (pmd_val(pmd) && !pmd_table(pmd)) +#define pmd_trans_splitting(pmd) (pmd_isset((pmd), PMD_SECT_SPLITTING)) #endif #define PMD_BIT_FUNC(fn,op) \ --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -214,12 +214,16 @@ static inline pte_t *pmd_page_vaddr(pmd_ #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0) +#define pte_isset(pte, val) ((u32)(val) == (val) ? pte_val(pte) & (val) \ + : !!(pte_val(pte) & (val))) +#define pte_isclear(pte, val) (!(pte_val(pte) & (val))) + #define pte_none(pte) (!pte_val(pte)) -#define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT) -#define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY)) -#define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY) -#define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG) -#define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN)) +#define pte_present(pte) (pte_isset((pte), L_PTE_PRESENT)) +#define pte_write(pte) (pte_isclear((pte), L_PTE_RDONLY)) +#define pte_dirty(pte) (pte_isset((pte), L_PTE_DIRTY)) +#define pte_young(pte) (pte_isset((pte), L_PTE_YOUNG)) +#define pte_exec(pte) (pte_isclear((pte), L_PTE_XN)) #define pte_special(pte) (0) #define pte_present_user(pte) (pte_present(pte) && (pte_val(pte) & L_PTE_USER)) -- 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/