From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757471AbbAZXba (ORCPT ); Mon, 26 Jan 2015 18:31:30 -0500 Received: from g2t1383g.austin.hp.com ([15.217.136.92]:57116 "EHLO g2t1383g.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757376AbbAZXaA (ORCPT ); Mon, 26 Jan 2015 18:30:00 -0500 From: Toshi Kani To: akpm@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, arnd@arndb.de, linux-mm@kvack.org Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Toshi Kani Subject: [RFC PATCH 2/7] lib: Add huge I/O map capability interfaces Date: Mon, 26 Jan 2015 16:13:24 -0700 Message-Id: <1422314009-31667-3-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1422314009-31667-1-git-send-email-toshi.kani@hp.com> References: <1422314009-31667-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings of pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities. A new kernel option "nohgiomap" is also added, so that user can disable the huge I/O map capabilities if necessary. Signed-off-by: Toshi Kani --- Documentation/kernel-parameters.txt | 2 ++ include/linux/io.h | 5 ++++ lib/ioremap.c | 44 +++++++++++++++++++++++++++++++++++ 3 files changed, 51 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 176d4fe..e3de01c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2304,6 +2304,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. register save and restore. The kernel will only save legacy floating-point registers on task switch. + nohgiomap [KNL,x86] Disable huge I/O mappings. + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. diff --git a/include/linux/io.h b/include/linux/io.h index fa02e55..8f5c8af 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -38,6 +38,11 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, } #endif +#ifdef CONFIG_HUGE_IOMAP +int arch_ioremap_pud_supported(void); +int arch_ioremap_pmd_supported(void); +#endif + /* * Managed iomap interface */ diff --git a/lib/ioremap.c b/lib/ioremap.c index 0c9216c..0a1ecb6 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -13,6 +13,44 @@ #include #include +#ifdef CONFIG_HUGE_IOMAP +int __read_mostly ioremap_pud_capable; +int __read_mostly ioremap_pmd_capable; +int __read_mostly ioremap_huge_disabled; + +static int __init set_nohgiomap(char *str) +{ + ioremap_huge_disabled = 1; + return 0; +} +early_param("nohgiomap", set_nohgiomap); + +static inline void ioremap_huge_init(void) +{ + if (!ioremap_huge_disabled) { + if (arch_ioremap_pud_supported()) + ioremap_pud_capable = 1; + if (arch_ioremap_pmd_supported()) + ioremap_pmd_capable = 1; + } +} + +static inline int ioremap_pud_enabled(void) +{ + return ioremap_pud_capable; +} + +static inline int ioremap_pmd_enabled(void) +{ + return ioremap_pmd_capable; +} + +#else /* !CONFIG_HUGE_IOMAP */ +static inline void ioremap_huge_init(void) { } +static inline int ioremap_pud_enabled(void) { return 0; } +static inline int ioremap_pmd_enabled(void) { return 0; } +#endif /* CONFIG_HUGE_IOMAP */ + static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { @@ -74,6 +112,12 @@ int ioremap_page_range(unsigned long addr, unsigned long start; unsigned long next; int err; + static int ioremap_huge_init_done; + + if (!ioremap_huge_init_done) { + ioremap_huge_init_done = 1; + ioremap_huge_init(); + } BUG_ON(addr >= end); From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qc0-f181.google.com (mail-qc0-f181.google.com [209.85.216.181]) by kanga.kvack.org (Postfix) with ESMTP id 6640F6B0070 for ; Mon, 26 Jan 2015 18:29:59 -0500 (EST) Received: by mail-qc0-f181.google.com with SMTP id l6so9622169qcy.12 for ; Mon, 26 Jan 2015 15:29:59 -0800 (PST) Received: from g6t1524.atlanta.hp.com (g6t1524.atlanta.hp.com. [15.193.200.67]) by mx.google.com with ESMTPS id 22si15367407qga.22.2015.01.26.15.29.58 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Jan 2015 15:29:58 -0800 (PST) From: Toshi Kani Subject: [RFC PATCH 2/7] lib: Add huge I/O map capability interfaces Date: Mon, 26 Jan 2015 16:13:24 -0700 Message-Id: <1422314009-31667-3-git-send-email-toshi.kani@hp.com> In-Reply-To: <1422314009-31667-1-git-send-email-toshi.kani@hp.com> References: <1422314009-31667-1-git-send-email-toshi.kani@hp.com> Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, arnd@arndb.de, linux-mm@kvack.org Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Toshi Kani Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings of pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities. A new kernel option "nohgiomap" is also added, so that user can disable the huge I/O map capabilities if necessary. Signed-off-by: Toshi Kani --- Documentation/kernel-parameters.txt | 2 ++ include/linux/io.h | 5 ++++ lib/ioremap.c | 44 +++++++++++++++++++++++++++++++++++ 3 files changed, 51 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 176d4fe..e3de01c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2304,6 +2304,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. register save and restore. The kernel will only save legacy floating-point registers on task switch. + nohgiomap [KNL,x86] Disable huge I/O mappings. + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. diff --git a/include/linux/io.h b/include/linux/io.h index fa02e55..8f5c8af 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -38,6 +38,11 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, } #endif +#ifdef CONFIG_HUGE_IOMAP +int arch_ioremap_pud_supported(void); +int arch_ioremap_pmd_supported(void); +#endif + /* * Managed iomap interface */ diff --git a/lib/ioremap.c b/lib/ioremap.c index 0c9216c..0a1ecb6 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -13,6 +13,44 @@ #include #include +#ifdef CONFIG_HUGE_IOMAP +int __read_mostly ioremap_pud_capable; +int __read_mostly ioremap_pmd_capable; +int __read_mostly ioremap_huge_disabled; + +static int __init set_nohgiomap(char *str) +{ + ioremap_huge_disabled = 1; + return 0; +} +early_param("nohgiomap", set_nohgiomap); + +static inline void ioremap_huge_init(void) +{ + if (!ioremap_huge_disabled) { + if (arch_ioremap_pud_supported()) + ioremap_pud_capable = 1; + if (arch_ioremap_pmd_supported()) + ioremap_pmd_capable = 1; + } +} + +static inline int ioremap_pud_enabled(void) +{ + return ioremap_pud_capable; +} + +static inline int ioremap_pmd_enabled(void) +{ + return ioremap_pmd_capable; +} + +#else /* !CONFIG_HUGE_IOMAP */ +static inline void ioremap_huge_init(void) { } +static inline int ioremap_pud_enabled(void) { return 0; } +static inline int ioremap_pmd_enabled(void) { return 0; } +#endif /* CONFIG_HUGE_IOMAP */ + static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { @@ -74,6 +112,12 @@ int ioremap_page_range(unsigned long addr, unsigned long start; unsigned long next; int err; + static int ioremap_huge_init_done; + + if (!ioremap_huge_init_done) { + ioremap_huge_init_done = 1; + ioremap_huge_init(); + } BUG_ON(addr >= end); -- 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