From 1219333dfdd488e85f08cf07881b8bc63cf92f21 Mon Sep 17 00:00:00 2001 From: "venkatesh.pallipadi@intel.com" Date: Tue, 18 Mar 2008 17:00:18 -0700 Subject: [PATCH] x86: PAT use reserve free memtype in set_memory_uc Use reserve_memtype and free_memtype interfaces in set_memory_uc/set_memory_wb interfaces to avoid aliasing. Usage model of set_memory_uc and set_memory_wb is for RAM memory and users will first call set_memory_uc and call set_memory_wb after use to reset the attribute. Signed-off-by: Venkatesh Pallipadi Signed-off-by: Suresh Siddha Signed-off-by: Ingo Molnar --- arch/x86/mm/ioremap.c | 4 ++-- arch/x86/mm/pageattr.c | 21 +++++++++++++++++++-- include/asm-x86/cacheflush.h | 2 ++ 3 files changed, 23 insertions(+), 4 deletions(-) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 20c01f2b2e..0cdb7f11ce 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -95,10 +95,10 @@ int ioremap_change_attr(unsigned long vaddr, unsigned long size, switch (prot_val) { case _PAGE_CACHE_UC: default: - err = set_memory_uc(vaddr, nrpages); + err = _set_memory_uc(vaddr, nrpages); break; case _PAGE_CACHE_WB: - err = set_memory_wb(vaddr, nrpages); + err = _set_memory_wb(vaddr, nrpages); break; } diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index f7d5ca170c..938df5e840 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -19,6 +19,7 @@ #include #include #include +#include /* * The current flushing context - we pass it instead of 5 arguments: @@ -770,18 +771,34 @@ static inline int change_page_attr_clear(unsigned long addr, int numpages, return change_page_attr_set_clr(addr, numpages, __pgprot(0), mask); } -int set_memory_uc(unsigned long addr, int numpages) +int _set_memory_uc(unsigned long addr, int numpages) { return change_page_attr_set(addr, numpages, __pgprot(_PAGE_CACHE_UC)); } + +int set_memory_uc(unsigned long addr, int numpages) +{ + if (reserve_memtype(addr, addr + numpages * PAGE_SIZE, + _PAGE_CACHE_UC, NULL)) + return -EINVAL; + + return _set_memory_uc(addr, numpages); +} EXPORT_SYMBOL(set_memory_uc); -int set_memory_wb(unsigned long addr, int numpages) +int _set_memory_wb(unsigned long addr, int numpages) { return change_page_attr_clear(addr, numpages, __pgprot(_PAGE_CACHE_MASK)); } + +int set_memory_wb(unsigned long addr, int numpages) +{ + free_memtype(addr, addr + numpages * PAGE_SIZE); + + return _set_memory_wb(addr, numpages); +} EXPORT_SYMBOL(set_memory_wb); int set_memory_x(unsigned long addr, int numpages) diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h index 5396c212d8..5676fba10a 100644 --- a/include/asm-x86/cacheflush.h +++ b/include/asm-x86/cacheflush.h @@ -34,6 +34,8 @@ int set_pages_nx(struct page *page, int numpages); int set_pages_ro(struct page *page, int numpages); int set_pages_rw(struct page *page, int numpages); +int _set_memory_uc(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_wb(unsigned long addr, int numpages); int set_memory_x(unsigned long addr, int numpages); -- 2.39.5