Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752381AbaKDWSs (ORCPT ); Tue, 4 Nov 2014 17:18:48 -0500 Received: from g4t3425.houston.hp.com ([15.201.208.53]:53333 "EHLO g4t3425.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752154AbaKDWSq (ORCPT ); Tue, 4 Nov 2014 17:18:46 -0500 From: Toshi Kani To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, akpm@linux-foundation.org, arnd@arndb.de Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, jgross@suse.com, stefan.bader@canonical.com, luto@amacapital.net, hmh@hmh.eng.br, yigal@plexistor.com, konrad.wilk@oracle.com, Toshi Kani Subject: [PATCH v5 2/8] x86, mm, pat, asm: Move [get|set]_page_memtype() to pat.c Date: Tue, 4 Nov 2014 15:04:32 -0700 Message-Id: <1415138678-22958-3-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1415138678-22958-1-git-send-email-toshi.kani@hp.com> References: <1415138678-22958-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [set|get]_page_memtype() are used by PAT and implemented under CONFIG_X86_PAT only. set_page_memtype() only handles three memory types, WB, WC and UC-, due to a limitation in the page flags. This patch moves [set|get]_page_memtype() to pat.c. This keeps them as PAT-internal functions and manages the limitation checked by the caller properly. Signed-off-by: Toshi Kani Suggested-by: Thomas Gleixner --- arch/x86/include/asm/cacheflush.h | 69 ------------------------------------- arch/x86/mm/pat.c | 58 +++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+), 69 deletions(-) diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h index 157644b..47c8e32 100644 --- a/arch/x86/include/asm/cacheflush.h +++ b/arch/x86/include/asm/cacheflush.h @@ -5,75 +5,6 @@ #include #include -#ifdef CONFIG_X86_PAT -/* - * X86 PAT uses page flags WC and Uncached together to keep track of - * memory type of pages that have backing page struct. X86 PAT supports 3 - * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and - * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not - * been changed from its default (value of -1 used to denote this). - * Note we do not support _PAGE_CACHE_MODE_UC here. - */ - -#define _PGMT_DEFAULT 0 -#define _PGMT_WC (1UL << PG_arch_1) -#define _PGMT_UC_MINUS (1UL << PG_uncached) -#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1) -#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1) -#define _PGMT_CLEAR_MASK (~_PGMT_MASK) - -static inline enum page_cache_mode get_page_memtype(struct page *pg) -{ - unsigned long pg_flags = pg->flags & _PGMT_MASK; - - if (pg_flags == _PGMT_DEFAULT) - return -1; - else if (pg_flags == _PGMT_WC) - return _PAGE_CACHE_MODE_WC; - else if (pg_flags == _PGMT_UC_MINUS) - return _PAGE_CACHE_MODE_UC_MINUS; - else - return _PAGE_CACHE_MODE_WB; -} - -static inline void set_page_memtype(struct page *pg, - enum page_cache_mode memtype) -{ - unsigned long memtype_flags; - unsigned long old_flags; - unsigned long new_flags; - - switch (memtype) { - case _PAGE_CACHE_MODE_WC: - memtype_flags = _PGMT_WC; - break; - case _PAGE_CACHE_MODE_UC_MINUS: - memtype_flags = _PGMT_UC_MINUS; - break; - case _PAGE_CACHE_MODE_WB: - memtype_flags = _PGMT_WB; - break; - default: - memtype_flags = _PGMT_DEFAULT; - break; - } - - do { - old_flags = pg->flags; - new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags; - } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags); -} -#else -static inline enum page_cache_mode get_page_memtype(struct page *pg) -{ - return -1; -} -static inline void set_page_memtype(struct page *pg, - enum page_cache_mode memtype) -{ -} -#endif - /* * The set_memory_* API can be used to change various attributes of a virtual * address range. The attributes include: diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index f43ab47..91c01b9 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -290,6 +291,63 @@ static int pat_pagerange_is_ram(resource_size_t start, resource_size_t end) } /* + * X86 PAT uses page flags WC and Uncached together to keep track of + * memory type of pages that have backing page struct. X86 PAT supports 3 + * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and + * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not + * been changed from its default (value of -1 used to denote this). + * Note we do not support _PAGE_CACHE_MODE_UC here. + */ +#define _PGMT_DEFAULT 0 +#define _PGMT_WC (1UL << PG_arch_1) +#define _PGMT_UC_MINUS (1UL << PG_uncached) +#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1) +#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1) +#define _PGMT_CLEAR_MASK (~_PGMT_MASK) + +static inline enum page_cache_mode get_page_memtype(struct page *pg) +{ + unsigned long pg_flags = pg->flags & _PGMT_MASK; + + if (pg_flags == _PGMT_DEFAULT) + return -1; + else if (pg_flags == _PGMT_WC) + return _PAGE_CACHE_MODE_WC; + else if (pg_flags == _PGMT_UC_MINUS) + return _PAGE_CACHE_MODE_UC_MINUS; + else + return _PAGE_CACHE_MODE_WB; +} + +static inline void set_page_memtype(struct page *pg, + enum page_cache_mode memtype) +{ + unsigned long memtype_flags; + unsigned long old_flags; + unsigned long new_flags; + + switch (memtype) { + case _PAGE_CACHE_MODE_WC: + memtype_flags = _PGMT_WC; + break; + case _PAGE_CACHE_MODE_UC_MINUS: + memtype_flags = _PGMT_UC_MINUS; + break; + case _PAGE_CACHE_MODE_WB: + memtype_flags = _PGMT_WB; + break; + default: + memtype_flags = _PGMT_DEFAULT; + break; + } + + do { + old_flags = pg->flags; + new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags; + } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags); +} + +/* * For RAM pages, we use page flags to mark the pages with appropriate type. * Here we do two pass: * - Find the memtype of all the pages in the range, look for any conflicts -- 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/