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flush icache before set_pte() on ia64: flush icache at set_pte

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Current ia64 kernel flushes icache by lazy_mmu_prot_update() *after*
set_pte().  This is too late.  This patch removes lazy_mmu_prot_update and
add modfied set_pte() for flushing if necessary.

This patch flush icache of a page when
	new pte has exec bit.
	&& new pte has present bit
	&& new pte is user's page.
	&& (old *ptep is not present
            || new pte's pfn is not same to old *ptep's ptn)
	&& new pte's page has no Pg_arch_1 bit.
	   Pg_arch_1 is set when a page is cache consistent.

I think this condition checks are much easier to understand than considering
"Where sync_icache_dcache() should be inserted ?".

pte_user() for ia64 was removed by http://lkml.org/lkml/2007/6/12/67 as
clean-up. So, I added it again.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KAMEZAWA Hiroyuki
2007-10-16 01:25:44 -07:00
committed by Linus Torvalds
parent 97ee052461
commit 954ffcb35f
9 changed files with 33 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

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

@ -125,10 +125,6 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres
#define pgd_offset_gate(mm, addr) pgd_offset(mm, addr)
#endif
#ifndef __HAVE_ARCH_LAZY_MMU_PROT_UPDATE
#define lazy_mmu_prot_update(pte) do { } while (0)
#endif
#ifndef __HAVE_ARCH_MOVE_PTE
#define move_pte(pte, prot, old_addr, new_addr) (pte)
#endif

44
include/asm-ia64/pgtable.h
View File

@ -223,12 +223,6 @@ ia64_phys_addr_valid (unsigned long addr)
* page table.
*/
/*
* On some architectures, special things need to be done when setting
* the PTE in a page table. Nothing special needs to be on IA-64.
*/
#define set_pte(ptep, pteval) (*(ptep) = (pteval))
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
#define VMALLOC_START (RGN_BASE(RGN_GATE) + 0x200000000UL)
#ifdef CONFIG_VIRTUAL_MEM_MAP
@ -320,6 +314,36 @@ ia64_phys_addr_valid (unsigned long addr)
#define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D))
#define pte_mkhuge(pte) (__pte(pte_val(pte)))
/*
* Because ia64's Icache and Dcache is not coherent (on a cpu), we need to
* sync icache and dcache when we insert *new* executable page.
* __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache
* if necessary.
*
* set_pte() is also called by the kernel, but we can expect that the kernel
* flushes icache explicitly if necessary.
*/
#define pte_present_exec_user(pte)\
((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \
(_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX))
extern void __ia64_sync_icache_dcache(pte_t pteval);
static inline void set_pte(pte_t *ptep, pte_t pteval)
{
/* page is present && page is user && page is executable
* && (page swapin or new page or page migraton
* || copy_on_write with page copying.)
*/
if (pte_present_exec_user(pteval) &&
(!pte_present(*ptep) ||
pte_pfn(*ptep) != pte_pfn(pteval)))
/* load_module() calles flush_icache_range() explicitly*/
__ia64_sync_icache_dcache(pteval);
*ptep = pteval;
}
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
/*
* Make page protection values cacheable, uncacheable, or write-
* combining. Note that "protection" is really a misnomer here as the
@ -489,12 +513,6 @@ extern struct page *zero_page_memmap_ptr;
#define HUGETLB_PGDIR_MASK (~(HUGETLB_PGDIR_SIZE-1))
#endif
/*
* IA-64 doesn't have any external MMU info: the page tables contain all the necessary
* information. However, we use this routine to take care of any (delayed) i-cache
* flushing that may be necessary.
*/
extern void lazy_mmu_prot_update (pte_t pte);
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
/*
@ -584,7 +602,7 @@ extern void lazy_mmu_prot_update (pte_t pte);
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTE_SAME
#define __HAVE_ARCH_PGD_OFFSET_GATE
#define __HAVE_ARCH_LAZY_MMU_PROT_UPDATE
#ifndef CONFIG_PGTABLE_4
#include <asm-generic/pgtable-nopud.h>