Introduce
two APIs for page attribute. flushing tlb/cache in every page
attribute is expensive. AGP gart usually will do a lot of operations to
change a page to uc, new APIs can reduce flush.
Signed-off-by: Shaohua Li <shaohua...@intel.com>
---
arch/x86/mm/pageattr.c | 58
+++++++++++++++++++++++++++++++++++++------
include/asm-x86/cacheflush.h | 3 ++
2 files changed, 53 insertions(+), 8 deletions(-)
Index: linux/arch/x86/mm/pageattr.c
===================================================================
--- linux.orig/arch/x86/mm/pageattr.c 2008-08-04 11:58:41.000000000
+0800
+++ linux/arch/x86/mm/pageattr.c 2008-08-04 12:04:58.000000000
+0800
@@ -752,12 +752,12 @@ static inline int cache_attr(pgprot_t at
(_PAGE_PAT | _PAGE_PAT_LARGE | _PAGE_PWT | _PAGE_PCD);
}
-static int change_page_attr_set_clr(unsigned long addr, int
numpages,
+static int do_change_page_attr_set_clr(unsigned long addr, int
numpages,
pgprot_t mask_set, pgprot_t
mask_clr,
- int force_split)
+ int force_split, int *tlb_flush)
{
struct cpa_data cpa;
- int ret, cache, checkalias;
+ int ret, checkalias;
/*
* Check, if we are requested to change a not supported
@@ -792,9 +792,22 @@ static int change_page_attr_set_clr(unsi
/*
* Check whether we really changed something:
*/
- if (!cpa.flushtlb)
- goto out;
+ *tlb_flush = cpa.flushtlb;
+ cpa_fill_pool(NULL);
+
+ return ret;
+}
+
+static int change_page_attr_set_clr(unsigned long addr, int numpages,
+ pgprot_t mask_set, pgprot_t
mask_clr,
+ int force_split)
+{
+ int cache, flush_cache = 0, ret;
+ ret = do_change_page_attr_set_clr(addr, numpages,
mask_set, mask_clr,
+ force_split, &flush_cache);
+ if (!flush_cache)
+ goto out;
/*
* No need to flush, when we did not set any of the caching
* attributes:
@@ -811,10 +824,7 @@ static int change_page_attr_set_clr(unsi
cpa_flush_range(addr, numpages, cache);
else
cpa_flush_all(cache);
-
out:
- cpa_fill_pool(NULL);
-
return ret;
}
@@ -852,6 +862,30 @@ int set_memory_uc(unsigned long addr, in
}
EXPORT_SYMBOL(set_memory_uc);
+int set_memory_uc_noflush(unsigned long addr, int numpages)
+{
+ int flush;
+ /*
+ * for now UC MINUS. see comments in ioremap_nocache()
+ */
+ if (reserve_memtype(addr, addr + numpages * PAGE_SIZE,
+ _PAGE_CACHE_UC_MINUS, NULL))
+ return -EINVAL;
+ /*
+ * for now UC MINUS. see comments in ioremap_nocache()
+ */
+ return do_change_page_attr_set_clr(addr, numpages,
+ __pgprot(_PAGE_CACHE_UC_MINUS),
+ __pgprot(0), 0, &flush);
+}
+EXPORT_SYMBOL(set_memory_uc_noflush);
+
+void set_memory_flush_all(void)
+{
+ cpa_flush_all(1);
+}
+EXPORT_SYMBOL(set_memory_flush_all);
+
int _set_memory_wc(unsigned long addr, int numpages)
{
return change_page_attr_set(addr, numpages,
@@ -926,6 +960,14 @@ int set_pages_uc(struct page *page, int
}
EXPORT_SYMBOL(set_pages_uc);
+int set_pages_uc_noflush(struct page *page, int numpages)
+{
+ unsigned long addr = (unsigned long)page_address(page);
+
+ return set_memory_uc_noflush(addr, numpages);
+}
+EXPORT_SYMBOL(set_pages_uc_noflush);
+
int set_pages_wb(struct page *page, int numpages)
{
unsigned long addr = (unsigned long)page_address(page);
Index: linux/include/asm-x86/cacheflush.h
===================================================================
--- linux.orig/include/asm-x86/cacheflush.h 2008-08-04
11:58:41.000000000 +0800
+++ linux/include/asm-x86/cacheflush.h 2008-08-04 12:05:16.000000000
+0800
@@ -57,6 +57,8 @@ int _set_memory_uc(unsigned long addr, i
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_uc_noflush(unsigned long addr, int numpages);
+void set_memory_flush_all(void);
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);
@@ -87,6 +89,7 @@ int set_memory_4k(unsigned long addr, in
*/
int set_pages_uc(struct page *page, int numpages);
+int set_pages_uc_noflush(struct page *page, int numpages);
int set_pages_wb(struct page *page, int numpages);
int set_pages_x(struct page *page, int numpages);
int set_pages_nx(struct page *page, int numpages);
--
