diff options
| -rw-r--r-- | arch/x86/xen/enlighten.c | 13 | ||||
| -rw-r--r-- | arch/x86/xen/mmu.c | 21 | ||||
| -rw-r--r-- | arch/x86/xen/mmu.h | 4 | ||||
| -rw-r--r-- | include/xen/interface/features.h | 3 | ||||
| -rw-r--r-- | include/xen/interface/xen.h | 9 |
5 files changed, 45 insertions, 5 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 0b7553cbc529..bd74229081c3 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -168,7 +168,9 @@ static void __init xen_banner(void) { printk(KERN_INFO "Booting paravirtualized kernel on %s\n", pv_info.name); - printk(KERN_INFO "Hypervisor signature: %s\n", xen_start_info->magic); + printk(KERN_INFO "Hypervisor signature: %s%s\n", + xen_start_info->magic, + xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); } static void xen_cpuid(unsigned int *ax, unsigned int *bx, @@ -1243,6 +1245,8 @@ asmlinkage void __init xen_start_kernel(void) BUG_ON(memcmp(xen_start_info->magic, "xen-3", 5) != 0); + xen_setup_features(); + /* Install Xen paravirt ops */ pv_info = xen_info; pv_init_ops = xen_init_ops; @@ -1252,14 +1256,17 @@ asmlinkage void __init xen_start_kernel(void) pv_apic_ops = xen_apic_ops; pv_mmu_ops = xen_mmu_ops; + if (xen_feature(XENFEAT_mmu_pt_update_preserve_ad)) { + pv_mmu_ops.ptep_modify_prot_start = xen_ptep_modify_prot_start; + pv_mmu_ops.ptep_modify_prot_commit = xen_ptep_modify_prot_commit; + } + machine_ops = xen_machine_ops; #ifdef CONFIG_SMP smp_ops = xen_smp_ops; #endif - xen_setup_features(); - /* Get mfn list */ if (!xen_feature(XENFEAT_auto_translated_physmap)) xen_build_dynamic_phys_to_machine(); diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 8132aa8c5d49..846dad7d54a5 100644 --- 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) { diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h index e3dd09e25c63..297bf9f5b8bc 100644 --- a/arch/x86/xen/mmu.h +++ b/arch/x86/xen/mmu.h @@ -52,4 +52,8 @@ void xen_set_pud_hyper(pud_t *ptr, pud_t val); void xen_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep); void xen_pmd_clear(pmd_t *pmdp); +pte_t xen_ptep_modify_prot_start(struct mm_struct *mm, unsigned long addr, pte_t *ptep); +void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pte); + #endif /* _XEN_MMU_H */ diff --git a/include/xen/interface/features.h b/include/xen/interface/features.h index d73228d16488..f51b6413b054 100644 --- a/include/xen/interface/features.h +++ b/include/xen/interface/features.h @@ -38,6 +38,9 @@ */ #define XENFEAT_pae_pgdir_above_4gb 4 +/* x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall? */ +#define XENFEAT_mmu_pt_update_preserve_ad 5 + #define XENFEAT_NR_SUBMAPS 1 #endif /* __XEN_PUBLIC_FEATURES_H__ */ diff --git a/include/xen/interface/xen.h b/include/xen/interface/xen.h index 819a0331cda9..2befa3e2f1bc 100644 --- a/include/xen/interface/xen.h +++ b/include/xen/interface/xen.h @@ -114,9 +114,14 @@ * ptr[:2] -- Machine address within the frame whose mapping to modify. * The frame must belong to the FD, if one is specified. * val -- Value to write into the mapping entry. + * + * ptr[1:0] == MMU_PT_UPDATE_PRESERVE_AD: + * As MMU_NORMAL_PT_UPDATE above, but A/D bits currently in the PTE are ORed + * with those in @val. */ -#define MMU_NORMAL_PT_UPDATE 0 /* checked '*ptr = val'. ptr is MA. */ -#define MMU_MACHPHYS_UPDATE 1 /* ptr = MA of frame to modify entry for */ +#define MMU_NORMAL_PT_UPDATE 0 /* checked '*ptr = val'. ptr is MA. */ +#define MMU_MACHPHYS_UPDATE 1 /* ptr = MA of frame to modify entry for */ +#define MMU_PT_UPDATE_PRESERVE_AD 2 /* atomically: *ptr = val | (*ptr&(A|D)) */ /* * MMU EXTENDED OPERATIONS |