x86: PAT add set_memory_wc() interface
Add a set_memory_wc interface(), similar to set_memory_uc interface.
Callers has to call set_memory_uc, set_memory_wb and
set_memory_wc, set_memory_wb as pairs.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 938df5e..270cab2e 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -787,6 +787,25 @@
}
EXPORT_SYMBOL(set_memory_uc);
+int _set_memory_wc(unsigned long addr, int numpages)
+{
+ return change_page_attr_set(addr, numpages,
+ __pgprot(_PAGE_CACHE_WC));
+}
+
+int set_memory_wc(unsigned long addr, int numpages)
+{
+ if (!pat_wc_enabled)
+ return set_memory_uc(addr, numpages);
+
+ if (reserve_memtype(addr, addr + numpages * PAGE_SIZE,
+ _PAGE_CACHE_WC, NULL))
+ return -EINVAL;
+
+ return _set_memory_wc(addr, numpages);
+}
+EXPORT_SYMBOL(set_memory_wc);
+
int _set_memory_wb(unsigned long addr, int numpages)
{
return change_page_attr_clear(addr, numpages,
diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h
index 5676fba..90437d3 100644
--- a/include/asm-x86/cacheflush.h
+++ b/include/asm-x86/cacheflush.h
@@ -35,8 +35,10 @@
int set_pages_rw(struct page *page, int numpages);
int _set_memory_uc(unsigned long addr, int numpages);
+int _set_memory_wc(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_wb(unsigned long addr, int numpages);
int set_memory_x(unsigned long addr, int numpages);
int set_memory_nx(unsigned long addr, int numpages);