Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753356AbbBYAPz (ORCPT ); Tue, 24 Feb 2015 19:15:55 -0500 Received: from g4t3425.houston.hp.com ([15.201.208.53]:46647 "EHLO g4t3425.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753315AbbBYAPu (ORCPT ); Tue, 24 Feb 2015 19:15:50 -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, Elliott@hp.com, Toshi Kani Subject: [PATCH v8 7/7] x86, mm: Add set_memory_wt() for WT Date: Tue, 24 Feb 2015 17:15:01 -0700 Message-Id: <1424823301-30927-8-git-send-email-toshi.kani@hp.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1424823301-30927-1-git-send-email-toshi.kani@hp.com> References: <1424823301-30927-1-git-send-email-toshi.kani@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7675 Lines: 204 This patch adds set_memory_wt(), set_memory_array_wt() and set_pages_array_wt() for setting specified range(s) of the regular memory to WT. Signed-off-by: Toshi Kani --- Documentation/x86/pat.txt | 9 ++++-- arch/x86/include/asm/cacheflush.h | 6 +++- arch/x86/mm/pageattr.c | 58 +++++++++++++++++++++++++++++++++---- 3 files changed, 63 insertions(+), 10 deletions(-) diff --git a/Documentation/x86/pat.txt b/Documentation/x86/pat.txt index be7b8c2..bf4339c 100644 --- a/Documentation/x86/pat.txt +++ b/Documentation/x86/pat.txt @@ -46,6 +46,9 @@ set_memory_uc | UC- | -- | -- | set_memory_wc | WC | -- | -- | set_memory_wb | | | | | | | | +set_memory_wt | WT | -- | -- | + set_memory_wb | | | | + | | | | pci sysfs resource | -- | -- | UC- | | | | | pci sysfs resource_wc | -- | -- | WC | @@ -117,8 +120,8 @@ can be more restrictive, in case of any existing aliasing for that address. For example: If there is an existing uncached mapping, a new ioremap_wc can return uncached mapping in place of write-combine requested. -set_memory_[uc|wc] and set_memory_wb should be used in pairs, where driver will -first make a region uc or wc and switch it back to wb after use. +set_memory_[uc|wc|wt] and set_memory_wb should be used in pairs, where driver +will first make a region uc, wc or wt and switch it back to wb after use. Over time writes to /proc/mtrr will be deprecated in favor of using PAT based interfaces. Users writing to /proc/mtrr are suggested to use above interfaces. @@ -126,7 +129,7 @@ interfaces. Users writing to /proc/mtrr are suggested to use above interfaces. Drivers should use ioremap_[uc|wc] to access PCI BARs with [uc|wc] access types. -Drivers should use set_memory_[uc|wc] to set access type for RAM ranges. +Drivers should use set_memory_[uc|wc|wt] to set access type for RAM ranges. PAT debugging diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h index 47c8e32..b6f7457 100644 --- a/arch/x86/include/asm/cacheflush.h +++ b/arch/x86/include/asm/cacheflush.h @@ -8,7 +8,7 @@ /* * The set_memory_* API can be used to change various attributes of a virtual * address range. The attributes include: - * Cachability : UnCached, WriteCombining, WriteBack + * Cachability : UnCached, WriteCombining, WriteThrough, WriteBack * Executability : eXeutable, NoteXecutable * Read/Write : ReadOnly, ReadWrite * Presence : NotPresent @@ -35,9 +35,11 @@ int _set_memory_uc(unsigned long addr, int numpages); int _set_memory_wc(unsigned long addr, int numpages); +int _set_memory_wt(unsigned long addr, int numpages); int _set_memory_wb(unsigned long addr, int numpages); int set_memory_uc(unsigned long addr, int numpages); int set_memory_wc(unsigned long addr, int numpages); +int set_memory_wt(unsigned long addr, int numpages); int set_memory_wb(unsigned long addr, int numpages); int set_memory_x(unsigned long addr, int numpages); int set_memory_nx(unsigned long addr, int numpages); @@ -48,10 +50,12 @@ int set_memory_4k(unsigned long addr, int numpages); int set_memory_array_uc(unsigned long *addr, int addrinarray); int set_memory_array_wc(unsigned long *addr, int addrinarray); +int set_memory_array_wt(unsigned long *addr, int addrinarray); int set_memory_array_wb(unsigned long *addr, int addrinarray); int set_pages_array_uc(struct page **pages, int addrinarray); int set_pages_array_wc(struct page **pages, int addrinarray); +int set_pages_array_wt(struct page **pages, int addrinarray); int set_pages_array_wb(struct page **pages, int addrinarray); /* diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 1965fc8..9308527 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -1504,12 +1504,10 @@ EXPORT_SYMBOL(set_memory_uc); static int _set_memory_array(unsigned long *addr, int addrinarray, enum page_cache_mode new_type) { + enum page_cache_mode set_type; int i, j; int ret; - /* - * for now UC MINUS. see comments in ioremap_nocache() - */ for (i = 0; i < addrinarray; i++) { ret = reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE, new_type, NULL); @@ -1517,9 +1515,12 @@ static int _set_memory_array(unsigned long *addr, int addrinarray, goto out_free; } + /* If WC, set to UC- first and then WC */ + set_type = (new_type == _PAGE_CACHE_MODE_WC) ? + _PAGE_CACHE_MODE_UC_MINUS : new_type; + ret = change_page_attr_set(addr, addrinarray, - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS), - 1); + cachemode2pgprot(set_type), 1); if (!ret && new_type == _PAGE_CACHE_MODE_WC) ret = change_page_attr_set_clr(addr, addrinarray, @@ -1551,6 +1552,12 @@ int set_memory_array_wc(unsigned long *addr, int addrinarray) } EXPORT_SYMBOL(set_memory_array_wc); +int set_memory_array_wt(unsigned long *addr, int addrinarray) +{ + return _set_memory_array(addr, addrinarray, _PAGE_CACHE_MODE_WT); +} +EXPORT_SYMBOL(set_memory_array_wt); + int _set_memory_wc(unsigned long addr, int numpages) { int ret; @@ -1591,6 +1598,34 @@ out_err: } EXPORT_SYMBOL(set_memory_wc); +int _set_memory_wt(unsigned long addr, int numpages) +{ + return change_page_attr_set(&addr, numpages, + cachemode2pgprot(_PAGE_CACHE_MODE_WT), 0); +} + +int set_memory_wt(unsigned long addr, int numpages) +{ + int ret; + + ret = reserve_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE, + _PAGE_CACHE_MODE_WT, NULL); + if (ret) + goto out_err; + + ret = _set_memory_wt(addr, numpages); + if (ret) + goto out_free; + + return 0; + +out_free: + free_memtype(__pa(addr), __pa(addr) + numpages * PAGE_SIZE); +out_err: + return ret; +} +EXPORT_SYMBOL(set_memory_wt); + int _set_memory_wb(unsigned long addr, int numpages) { /* WB cache mode is hard wired to all cache attribute bits being 0 */ @@ -1683,6 +1718,7 @@ static int _set_pages_array(struct page **pages, int addrinarray, { unsigned long start; unsigned long end; + enum page_cache_mode set_type; int i; int free_idx; int ret; @@ -1696,8 +1732,12 @@ static int _set_pages_array(struct page **pages, int addrinarray, goto err_out; } + /* If WC, set to UC- first and then WC */ + set_type = (new_type == _PAGE_CACHE_MODE_WC) ? + _PAGE_CACHE_MODE_UC_MINUS : new_type; + ret = cpa_set_pages_array(pages, addrinarray, - cachemode2pgprot(_PAGE_CACHE_MODE_UC_MINUS)); + cachemode2pgprot(set_type)); if (!ret && new_type == _PAGE_CACHE_MODE_WC) ret = change_page_attr_set_clr(NULL, addrinarray, cachemode2pgprot( @@ -1731,6 +1771,12 @@ int set_pages_array_wc(struct page **pages, int addrinarray) } EXPORT_SYMBOL(set_pages_array_wc); +int set_pages_array_wt(struct page **pages, int addrinarray) +{ + return _set_pages_array(pages, addrinarray, _PAGE_CACHE_MODE_WT); +} +EXPORT_SYMBOL(set_pages_array_wt); + int set_pages_wb(struct page *page, int numpages) { unsigned long addr = (unsigned long)page_address(page); -- 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/