Re: [PATCH 1 of 4] mm: add a ptep_modify_prot transaction abstraction
From: Jeremy Fitzhardinge <hidden>
Date: 2008-06-19 00:16:28
Also in:
lkml, xen-devel
From: Jeremy Fitzhardinge <hidden>
Date: 2008-06-19 00:16:28
Also in:
lkml, xen-devel
Jeremy Fitzhardinge wrote:
Benjamin Herrenschmidt wrote:quoted
On Mon, 2008-06-16 at 04:30 -0700, Jeremy Fitzhardinge wrote:quoted
The only current user of this interface is mprotectDo you plan to use it with fork ultimately ?Good point, I'd overlooked that. I guess that means using it in ptep_set_wrprotect().
Along the lines of:
--- a/include/asm-x86/pgtable.h Wed Jun 18 13:54:49 2008 -0700
+++ b/include/asm-x86/pgtable.h Wed Jun 18 17:03:39 2008 -0700@@ -491,7 +491,11 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte); + pte_t pte = ptep_modify_prot_start(mm, addr, ptep); + + pte = pte_wrprotect(pte); + + ptep_modify_prot_commit(mm, addr, ptep, pte); pte_update(mm, addr, ptep); }
J