From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f175.google.com (mail-ob0-f175.google.com [209.85.214.175]) by kanga.kvack.org (Postfix) with ESMTP id E6E116B006E for ; Tue, 3 Mar 2015 12:45:09 -0500 (EST) Received: by obcwp4 with SMTP id wp4so1304232obc.0 for ; Tue, 03 Mar 2015 09:45:09 -0800 (PST) Received: from g1t5424.austin.hp.com (g1t5424.austin.hp.com. [15.216.225.54]) by mx.google.com with ESMTPS id as5si720968obd.86.2015.03.03.09.45.08 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Mar 2015 09:45:09 -0800 (PST) From: Toshi Kani Subject: [PATCH v3 2/6] lib: Add huge I/O map capability interfaces Date: Tue, 3 Mar 2015 10:44:20 -0700 Message-Id: <1425404664-19675-3-git-send-email-toshi.kani@hp.com> In-Reply-To: <1425404664-19675-1-git-send-email-toshi.kani@hp.com> References: <1425404664-19675-1-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 Cc: linux-mm@kvack.org, x86@kernel.org, linux-kernel@vger.kernel.org, dave.hansen@intel.com, Elliott@hp.com, Toshi Kani Added ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings with pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities at boot-time. A new kernel option "nohugeiomap" is also added, so that user can disable the huge I/O map capabilities when necessary. Signed-off-by: Toshi Kani --- Documentation/kernel-parameters.txt | 2 ++ arch/Kconfig | 3 +++ include/linux/io.h | 7 ++++++ init/main.c | 2 ++ lib/ioremap.c | 38 +++++++++++++++++++++++++++++++++++ 5 files changed, 52 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index bfcb1a6..55a4ec7 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2321,6 +2321,8 @@ 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. + nohugeiomap [KNL,x86] Disable kernel 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/arch/Kconfig b/arch/Kconfig index 05d7a8a..55c4440 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -446,6 +446,9 @@ config HAVE_IRQ_TIME_ACCOUNTING config HAVE_ARCH_TRANSPARENT_HUGEPAGE bool +config HAVE_ARCH_HUGE_VMAP + bool + config HAVE_ARCH_SOFT_DIRTY bool diff --git a/include/linux/io.h b/include/linux/io.h index fa02e55..1ce8b4e 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -38,6 +38,13 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, } #endif +void __init ioremap_huge_init(void); + +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +int arch_ioremap_pud_supported(void); +int arch_ioremap_pmd_supported(void); +#endif + /* * Managed iomap interface */ diff --git a/init/main.c b/init/main.c index 6f0f1c5f..119cdf1 100644 --- a/init/main.c +++ b/init/main.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include @@ -484,6 +485,7 @@ static void __init mm_init(void) percpu_init_late(); pgtable_init(); vmalloc_init(); + ioremap_huge_init(); } asmlinkage __visible void __init start_kernel(void) diff --git a/lib/ioremap.c b/lib/ioremap.c index 0c9216c..0ce18aa 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -13,6 +13,44 @@ #include #include +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +int __read_mostly ioremap_pud_capable; +int __read_mostly ioremap_pmd_capable; +int __read_mostly ioremap_huge_disabled; + +static int __init set_nohugeiomap(char *str) +{ + ioremap_huge_disabled = 1; + return 0; +} +early_param("nohugeiomap", set_nohugeiomap); + +void __init 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_HAVE_ARCH_HUGE_VMAP */ +void __init ioremap_huge_init(void) { } +static inline int ioremap_pud_enabled(void) { return 0; } +static inline int ioremap_pmd_enabled(void) { return 0; } +#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ + static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { -- 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