xen: implement ptep_modify_prot_start/commit

[linux-2.6-omap-h63xx.git] / arch / x86 / xen / mmu.c

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 8132aa8c5d49d2797b1a3c30333cb89df6cbe9fd..846dad7d54a5ed6162c41a5fa1da9b2646b09300 100644 (file)
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -323,6 +323,27 @@ out:
                preempt_enable();
 }
 
+pte_t xen_ptep_modify_prot_start(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
+{
+       /* Just return the pte as-is.  We preserve the bits on commit */
+       return *ptep;
+}
+
+void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
+                                pte_t *ptep, pte_t pte)
+{
+       struct multicall_space mcs;
+       struct mmu_update *u;
+
+       mcs = xen_mc_entry(sizeof(*u));
+       u = mcs.args;
+       u->ptr = virt_to_machine(ptep).maddr | MMU_PT_UPDATE_PRESERVE_AD;
+       u->val = pte_val_ma(pte);
+       MULTI_mmu_update(mcs.mc, u, 1, NULL, DOMID_SELF);
+
+       xen_mc_issue(PARAVIRT_LAZY_MMU);
+}
+
 /* Assume pteval_t is equivalent to all the other *val_t types. */
 static pteval_t pte_mfn_to_pfn(pteval_t val)
 {