From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757370AbbAZX34 (ORCPT ); Mon, 26 Jan 2015 18:29:56 -0500 Received: from g9t1613g.houston.hp.com ([15.240.0.71]:54941 "EHLO g9t1613g.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754575AbbAZX3x (ORCPT ); Mon, 26 Jan 2015 18:29:53 -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 Subject: [RFC PATCH 0/7] Kernel huge I/O mapping support Date: Mon, 26 Jan 2015 16:13:22 -0700 Message-Id: <1422314009-31667-1-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.9.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ioremap() and its related interfaces are used to create I/O mappings to memory-mapped I/O devices. The mapping sizes of the traditional I/O devices are relatively small. Non-volatile memory (NVM), however, has many GB and is going to have TB soon. It is not very efficient to create large I/O mappings with 4KB. This patch extends the ioremap() interfaces to transparently create I/O mappings with huge pages. There is no change necessary to the drivers using ioremap(). Using huge pages will improve performance of NVM and other devices with large memory, and reduce the time to create their mappings as well. The patchset introduces the following configs: HUGE_IOMAP - When selected, enable huge I/O mappings. Require HAVE_ARCH_HUGE_VMAP set. HAVE_ARCH_HUGE_VMAP - Indicate arch supports huge KVA mappings Patch 1-4 changes common files to support huge I/O mappings. There is no change in the functinalities until HUGE_IOMAP is set in patch 7. Patch 5,6 implement HAVE_ARCH_HUGE_VMAP and HUGE_IOMAP funcs on x86, and set HAVE_ARCH_HUGE_VMAP on x86. Patch 7 adds HUGE_IOMAP to Kconfig, which is set to Y by default on x86. --- Toshi Kani (7): 1/7 mm: Change __get_vm_area_node() to use fls_long() 2/7 lib: Add huge I/O map capability interfaces 3/7 mm: Change ioremap to set up huge I/O mappings 4/7 mm: Change vunmap to tear down huge KVA mappings 5/7 x86, mm: Support huge KVA mappings on x86 6/7 x86, mm: Support huge I/O mappings on x86 7/7 mm: Add config HUGE_IOMAP to enable huge I/O mappings --- Documentation/kernel-parameters.txt | 2 ++ arch/Kconfig | 3 ++ arch/x86/Kconfig | 1 + arch/x86/include/asm/page_types.h | 8 +++++ arch/x86/mm/ioremap.c | 16 ++++++++++ arch/x86/mm/pgtable.c | 32 ++++++++++++++++++++ include/asm-generic/pgtable.h | 12 ++++++++ include/linux/io.h | 5 ++++ lib/ioremap.c | 60 +++++++++++++++++++++++++++++++++++++ mm/Kconfig | 10 +++++++ mm/vmalloc.c | 8 ++++- 11 files changed, 156 insertions(+), 1 deletion(-) From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f50.google.com (mail-qa0-f50.google.com [209.85.216.50]) by kanga.kvack.org (Postfix) with ESMTP id B19136B0032 for ; Mon, 26 Jan 2015 18:29:52 -0500 (EST) Received: by mail-qa0-f50.google.com with SMTP id k15so9229747qaq.9 for ; Mon, 26 Jan 2015 15:29:52 -0800 (PST) Received: from g6t1526.atlanta.hp.com (g6t1526.atlanta.hp.com. [15.193.200.69]) by mx.google.com with ESMTPS id h11si15358482qaq.18.2015.01.26.15.29.51 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Jan 2015 15:29:52 -0800 (PST) From: Toshi Kani Subject: [RFC PATCH 0/7] Kernel huge I/O mapping support Date: Mon, 26 Jan 2015 16:13:22 -0700 Message-Id: <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 ioremap() and its related interfaces are used to create I/O mappings to memory-mapped I/O devices. The mapping sizes of the traditional I/O devices are relatively small. Non-volatile memory (NVM), however, has many GB and is going to have TB soon. It is not very efficient to create large I/O mappings with 4KB. This patch extends the ioremap() interfaces to transparently create I/O mappings with huge pages. There is no change necessary to the drivers using ioremap(). Using huge pages will improve performance of NVM and other devices with large memory, and reduce the time to create their mappings as well. The patchset introduces the following configs: HUGE_IOMAP - When selected, enable huge I/O mappings. Require HAVE_ARCH_HUGE_VMAP set. HAVE_ARCH_HUGE_VMAP - Indicate arch supports huge KVA mappings Patch 1-4 changes common files to support huge I/O mappings. There is no change in the functinalities until HUGE_IOMAP is set in patch 7. Patch 5,6 implement HAVE_ARCH_HUGE_VMAP and HUGE_IOMAP funcs on x86, and set HAVE_ARCH_HUGE_VMAP on x86. Patch 7 adds HUGE_IOMAP to Kconfig, which is set to Y by default on x86. --- Toshi Kani (7): 1/7 mm: Change __get_vm_area_node() to use fls_long() 2/7 lib: Add huge I/O map capability interfaces 3/7 mm: Change ioremap to set up huge I/O mappings 4/7 mm: Change vunmap to tear down huge KVA mappings 5/7 x86, mm: Support huge KVA mappings on x86 6/7 x86, mm: Support huge I/O mappings on x86 7/7 mm: Add config HUGE_IOMAP to enable huge I/O mappings --- Documentation/kernel-parameters.txt | 2 ++ arch/Kconfig | 3 ++ arch/x86/Kconfig | 1 + arch/x86/include/asm/page_types.h | 8 +++++ arch/x86/mm/ioremap.c | 16 ++++++++++ arch/x86/mm/pgtable.c | 32 ++++++++++++++++++++ include/asm-generic/pgtable.h | 12 ++++++++ include/linux/io.h | 5 ++++ lib/ioremap.c | 60 +++++++++++++++++++++++++++++++++++++ mm/Kconfig | 10 +++++++ mm/vmalloc.c | 8 ++++- 11 files changed, 156 insertions(+), 1 deletion(-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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