lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86: PAT: add pgprot_writecombine() interface for drivers - v3

Browse Source 
Impact: New mm functionality.

Add pgprot_writecombine. pgprot_writecombine will be aliased to
pgprot_noncached when not supported by the architecture.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
venkatesh.pallipadi@intel.com
2008-12-18 11:41:32 -08:00
committed by H. Peter Anvin
parent 8a7b12f70f
commit 2520bd3123
3 changed files with 15 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
arch/x86/include/asm/pgtable.h
View File

@@ -168,6 +168,9 @@
#ifndef __ASSEMBLY__ #ifndef __ASSEMBLY__
#define pgprot_writecombine pgprot_writecombine
extern pgprot_t pgprot_writecombine(pgprot_t prot);
/* /*
* ZERO_PAGE is a global shared page that is always zero: used * ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc.. * for zero-mapped memory areas etc..

8
arch/x86/mm/pat.c
View File

@@ -832,6 +832,14 @@ void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
} }
} }
pgprot_t pgprot_writecombine(pgprot_t prot)
{
if (pat_enabled)
return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC);
else
return pgprot_noncached(prot);
}
#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT) #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_PAT)
/* get Nth element of the linked list */ /* get Nth element of the linked list */

4
include/asm-generic/pgtable.h
View File

@@ -129,6 +129,10 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
#define move_pte(pte, prot, old_addr, new_addr) (pte) #define move_pte(pte, prot, old_addr, new_addr) (pte)
#endif #endif
#ifndef pgprot_writecombine
#define pgprot_writecombine pgprot_noncached
#endif
/* /*
* When walking page tables, get the address of the next boundary, * When walking page tables, get the address of the next boundary,
* or the end address of the range if that comes earlier. Although no * or the end address of the range if that comes earlier. Although no