Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 1ac2f7d5 authored by Shaohua Li's avatar Shaohua Li Committed by Ingo Molnar
Browse files

introduce two APIs for page attribute 



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: default avatarShaohua Li <shaohua.li@intel.com>
Cc: airlied@linux.ie
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 012f09e7

arch/x86/mm/pageattr.c

+50 −8
Original line number Diff line number Diff line
@@ -752,12 +752,12 @@ static inline int cache_attr(pgprot_t attr) 
		(_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(unsigned long addr, int numpages, 
	/*

	 * 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(unsigned long addr, int numpages, 
		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, int numpages) 
}

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 numpages) 
}

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);

include/asm-x86/cacheflush.h

+3 −0
Original line number Diff line number Diff line
@@ -57,6 +57,8 @@ 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_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, int numpages); 
 */



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);