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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-16 13:06:27 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-16 13:06:27 -0800
commit051089a2eed9a9977080774f3793ff2688cd3878 (patch)
tree29e23a60ea7e98633a3eef8dd436b57d7d41986d /arch
parent974aa5630b318938273d7efe7a2cf031c7b927db (diff)
parent646d944c2ef5a3b298c4e150494c71b9272d8b47 (diff)
Merge tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross: "Xen features and fixes for v4.15-rc1 Apart from several small fixes it contains the following features: - a series by Joao Martins to add vdso support of the pv clock interface - a series by Juergen Gross to add support for Xen pv guests to be able to run on 5 level paging hosts - a series by Stefano Stabellini adding the Xen pvcalls frontend driver using a paravirtualized socket interface" * tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (34 commits) xen/pvcalls: fix potential endless loop in pvcalls-front.c xen/pvcalls: Add MODULE_LICENSE() MAINTAINERS: xen, kvm: track pvclock-abi.h changes x86/xen/time: setup vcpu 0 time info page x86/xen/time: set pvclock flags on xen_time_init() x86/pvclock: add setter for pvclock_pvti_cpu0_va ptp_kvm: probe for kvm guest availability xen/privcmd: remove unused variable pageidx xen: select grant interface version xen: update arch/x86/include/asm/xen/cpuid.h xen: add grant interface version dependent constants to gnttab_ops xen: limit grant v2 interface to the v1 functionality xen: re-introduce support for grant v2 interface xen: support priv-mapping in an HVM tools domain xen/pvcalls: remove redundant check for irq >= 0 xen/pvcalls: fix unsigned less than zero error check xen/time: Return -ENODEV from xen_get_wallclock() xen/pvcalls-front: mark expected switch fall-through xen: xenbus_probe_frontend: mark expected switch fall-throughs xen/time: do not decrease steal time after live migration on xen ...
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/xen/grant-table.c9
-rw-r--r--arch/x86/entry/vdso/vma.c2
-rw-r--r--arch/x86/include/asm/pvclock.h19
-rw-r--r--arch/x86/include/asm/xen/cpuid.h42
-rw-r--r--arch/x86/include/asm/xen/page.h11
-rw-r--r--arch/x86/kernel/kvmclock.c7
-rw-r--r--arch/x86/kernel/pvclock.c14
-rw-r--r--arch/x86/xen/grant-table.c60
-rw-r--r--arch/x86/xen/mmu.c14
-rw-r--r--arch/x86/xen/mmu_pv.c4
-rw-r--r--arch/x86/xen/suspend.c4
-rw-r--r--arch/x86/xen/time.c99
-rw-r--r--arch/x86/xen/xen-ops.h2
13 files changed, 249 insertions, 38 deletions
diff --git a/arch/arm/xen/grant-table.c b/arch/arm/xen/grant-table.c
index e43791829ace..91cf08ba1e95 100644
--- a/arch/arm/xen/grant-table.c
+++ b/arch/arm/xen/grant-table.c
@@ -45,7 +45,14 @@ void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
return;
}
-int arch_gnttab_init(unsigned long nr_shared)
+int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
+ unsigned long max_nr_gframes,
+ grant_status_t **__shared)
+{
+ return -ENOSYS;
+}
+
+int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
{
return 0;
}
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index d63053142b16..5b8b556dbb12 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -112,7 +112,7 @@ static int vvar_fault(const struct vm_special_mapping *sm,
__pa_symbol(&__vvar_page) >> PAGE_SHIFT);
} else if (sym_offset == image->sym_pvclock_page) {
struct pvclock_vsyscall_time_info *pvti =
- pvclock_pvti_cpu0_va();
+ pvclock_get_pvti_cpu0_va();
if (pvti && vclock_was_used(VCLOCK_PVCLOCK)) {
ret = vm_insert_pfn_prot(
vma,
diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index 3e4ed8fb5f91..a7471dcd2205 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h
@@ -5,15 +5,6 @@
#include <linux/clocksource.h>
#include <asm/pvclock-abi.h>
-#ifdef CONFIG_KVM_GUEST
-extern struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void);
-#else
-static inline struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
-{
- return NULL;
-}
-#endif
-
/* some helper functions for xen and kvm pv clock sources */
u64 pvclock_clocksource_read(struct pvclock_vcpu_time_info *src);
u8 pvclock_read_flags(struct pvclock_vcpu_time_info *src);
@@ -102,4 +93,14 @@ struct pvclock_vsyscall_time_info {
#define PVTI_SIZE sizeof(struct pvclock_vsyscall_time_info)
+#ifdef CONFIG_PARAVIRT_CLOCK
+void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti);
+struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void);
+#else
+static inline struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void)
+{
+ return NULL;
+}
+#endif
+
#endif /* _ASM_X86_PVCLOCK_H */
diff --git a/arch/x86/include/asm/xen/cpuid.h b/arch/x86/include/asm/xen/cpuid.h
index 3bdd10d71223..a9630104f1c4 100644
--- a/arch/x86/include/asm/xen/cpuid.h
+++ b/arch/x86/include/asm/xen/cpuid.h
@@ -74,21 +74,43 @@
#define XEN_CPUID_FEAT1_MMU_PT_UPDATE_PRESERVE_AD (1u<<0)
/*
+ * Leaf 4 (0x40000x03)
+ * Sub-leaf 0: EAX: bit 0: emulated tsc
+ * bit 1: host tsc is known to be reliable
+ * bit 2: RDTSCP instruction available
+ * EBX: tsc_mode: 0=default (emulate if necessary), 1=emulate,
+ * 2=no emulation, 3=no emulation + TSC_AUX support
+ * ECX: guest tsc frequency in kHz
+ * EDX: guest tsc incarnation (migration count)
+ * Sub-leaf 1: EAX: tsc offset low part
+ * EBX: tsc offset high part
+ * ECX: multiplicator for tsc->ns conversion
+ * EDX: shift amount for tsc->ns conversion
+ * Sub-leaf 2: EAX: host tsc frequency in kHz
+ */
+
+/*
* Leaf 5 (0x40000x04)
* HVM-specific features
- * EAX: Features
- * EBX: vcpu id (iff EAX has XEN_HVM_CPUID_VCPU_ID_PRESENT flag)
+ * Sub-leaf 0: EAX: Features
+ * Sub-leaf 0: EBX: vcpu id (iff EAX has XEN_HVM_CPUID_VCPU_ID_PRESENT flag)
*/
-
-/* Virtualized APIC registers */
-#define XEN_HVM_CPUID_APIC_ACCESS_VIRT (1u << 0)
-/* Virtualized x2APIC accesses */
-#define XEN_HVM_CPUID_X2APIC_VIRT (1u << 1)
+#define XEN_HVM_CPUID_APIC_ACCESS_VIRT (1u << 0) /* Virtualized APIC registers */
+#define XEN_HVM_CPUID_X2APIC_VIRT (1u << 1) /* Virtualized x2APIC accesses */
/* Memory mapped from other domains has valid IOMMU entries */
#define XEN_HVM_CPUID_IOMMU_MAPPINGS (1u << 2)
-/* vcpu id is present in EBX */
-#define XEN_HVM_CPUID_VCPU_ID_PRESENT (1u << 3)
+#define XEN_HVM_CPUID_VCPU_ID_PRESENT (1u << 3) /* vcpu id is present in EBX */
+
+/*
+ * Leaf 6 (0x40000x05)
+ * PV-specific parameters
+ * Sub-leaf 0: EAX: max available sub-leaf
+ * Sub-leaf 0: EBX: bits 0-7: max machine address width
+ */
+
+/* Max. address width in bits taking memory hotplug into account. */
+#define XEN_CPUID_MACHINE_ADDRESS_WIDTH_MASK (0xffu << 0)
-#define XEN_CPUID_MAX_NUM_LEAVES 4
+#define XEN_CPUID_MAX_NUM_LEAVES 5
#endif /* __XEN_PUBLIC_ARCH_X86_CPUID_H__ */
diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h
index c6b84245e5ab..123e669bf363 100644
--- a/arch/x86/include/asm/xen/page.h
+++ b/arch/x86/include/asm/xen/page.h
@@ -27,6 +27,15 @@ typedef struct xpaddr {
phys_addr_t paddr;
} xpaddr_t;
+#ifdef CONFIG_X86_64
+#define XEN_PHYSICAL_MASK __sme_clr((1UL << 52) - 1)
+#else
+#define XEN_PHYSICAL_MASK __PHYSICAL_MASK
+#endif
+
+#define XEN_PTE_MFN_MASK ((pteval_t)(((signed long)PAGE_MASK) & \
+ XEN_PHYSICAL_MASK))
+
#define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
@@ -278,7 +287,7 @@ static inline unsigned long bfn_to_local_pfn(unsigned long mfn)
static inline unsigned long pte_mfn(pte_t pte)
{
- return (pte.pte & PTE_PFN_MASK) >> PAGE_SHIFT;
+ return (pte.pte & XEN_PTE_MFN_MASK) >> PAGE_SHIFT;
}
static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index 77b492c2d658..8b26c9e01cc4 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -48,12 +48,6 @@ early_param("no-kvmclock", parse_no_kvmclock);
static struct pvclock_vsyscall_time_info *hv_clock;
static struct pvclock_wall_clock *wall_clock;
-struct pvclock_vsyscall_time_info *pvclock_pvti_cpu0_va(void)
-{
- return hv_clock;
-}
-EXPORT_SYMBOL_GPL(pvclock_pvti_cpu0_va);
-
/*
* The wallclock is the time of day when we booted. Since then, some time may
* have elapsed since the hypervisor wrote the data. So we try to account for
@@ -377,6 +371,7 @@ int __init kvm_setup_vsyscall_timeinfo(void)
return 1;
}
+ pvclock_set_pvti_cpu0_va(hv_clock);
put_cpu();
kvm_clock.archdata.vclock_mode = VCLOCK_PVCLOCK;
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index 5c3f6d6a5078..761f6af6efa5 100644
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -25,8 +25,10 @@
#include <asm/fixmap.h>
#include <asm/pvclock.h>
+#include <asm/vgtod.h>
static u8 valid_flags __read_mostly = 0;
+static struct pvclock_vsyscall_time_info *pvti_cpu0_va __read_mostly;
void pvclock_set_flags(u8 flags)
{
@@ -144,3 +146,15 @@ void pvclock_read_wallclock(struct pvclock_wall_clock *wall_clock,
set_normalized_timespec(ts, now.tv_sec, now.tv_nsec);
}
+
+void pvclock_set_pvti_cpu0_va(struct pvclock_vsyscall_time_info *pvti)
+{
+ WARN_ON(vclock_was_used(VCLOCK_PVCLOCK));
+ pvti_cpu0_va = pvti;
+}
+
+struct pvclock_vsyscall_time_info *pvclock_get_pvti_cpu0_va(void)
+{
+ return pvti_cpu0_va;
+}
+EXPORT_SYMBOL_GPL(pvclock_get_pvti_cpu0_va);
diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index 809b6c812654..92ccc718152d 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -49,7 +49,7 @@
static struct gnttab_vm_area {
struct vm_struct *area;
pte_t **ptes;
-} gnttab_shared_vm_area;
+} gnttab_shared_vm_area, gnttab_status_vm_area;
int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
unsigned long max_nr_gframes,
@@ -73,16 +73,43 @@ int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
return 0;
}
+int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
+ unsigned long max_nr_gframes,
+ grant_status_t **__shared)
+{
+ grant_status_t *shared = *__shared;
+ unsigned long addr;
+ unsigned long i;
+
+ if (shared == NULL)
+ *__shared = shared = gnttab_status_vm_area.area->addr;
+
+ addr = (unsigned long)shared;
+
+ for (i = 0; i < nr_gframes; i++) {
+ set_pte_at(&init_mm, addr, gnttab_status_vm_area.ptes[i],
+ mfn_pte(frames[i], PAGE_KERNEL));
+ addr += PAGE_SIZE;
+ }
+
+ return 0;
+}
+
void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
{
+ pte_t **ptes;
unsigned long addr;
unsigned long i;
+ if (shared == gnttab_status_vm_area.area->addr)
+ ptes = gnttab_status_vm_area.ptes;
+ else
+ ptes = gnttab_shared_vm_area.ptes;
+
addr = (unsigned long)shared;
for (i = 0; i < nr_gframes; i++) {
- set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
- __pte(0));
+ set_pte_at(&init_mm, addr, ptes[i], __pte(0));
addr += PAGE_SIZE;
}
}
@@ -102,12 +129,35 @@ static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
return 0;
}
-int arch_gnttab_init(unsigned long nr_shared)
+static void arch_gnttab_vfree(struct gnttab_vm_area *area)
{
+ free_vm_area(area->area);
+ kfree(area->ptes);
+}
+
+int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
+{
+ int ret;
+
if (!xen_pv_domain())
return 0;
- return arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
+ ret = arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Always allocate the space for the status frames in case
+ * we're migrated to a host with V2 support.
+ */
+ ret = arch_gnttab_valloc(&gnttab_status_vm_area, nr_status);
+ if (ret < 0)
+ goto err;
+
+ return 0;
+err:
+ arch_gnttab_vfree(&gnttab_shared_vm_area);
+ return -ENOMEM;
}
#ifdef CONFIG_XEN_PVH
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 3e15345abfe7..d33e7dbe3129 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -172,6 +172,9 @@ int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
pgprot_t prot, unsigned domid,
struct page **pages)
{
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return -EOPNOTSUPP;
+
return do_remap_gfn(vma, addr, &gfn, nr, NULL, prot, domid, pages);
}
EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
@@ -182,6 +185,10 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
int *err_ptr, pgprot_t prot,
unsigned domid, struct page **pages)
{
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
+ prot, domid, pages);
+
/* We BUG_ON because it's a programmer error to pass a NULL err_ptr,
* and the consequences later is quite hard to detect what the actual
* cause of "wrong memory was mapped in".
@@ -193,9 +200,12 @@ EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
/* Returns: 0 success */
int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
- int numpgs, struct page **pages)
+ int nr, struct page **pages)
{
- if (!pages || !xen_feature(XENFEAT_auto_translated_physmap))
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return xen_xlate_unmap_gfn_range(vma, nr, pages);
+
+ if (!pages)
return 0;
return -EINVAL;
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index 2ccdaba31a07..fc048ec686e7 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -315,7 +315,7 @@ void xen_ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
static pteval_t pte_mfn_to_pfn(pteval_t val)
{
if (val & _PAGE_PRESENT) {
- unsigned long mfn = (val & PTE_PFN_MASK) >> PAGE_SHIFT;
+ unsigned long mfn = (val & XEN_PTE_MFN_MASK) >> PAGE_SHIFT;
unsigned long pfn = mfn_to_pfn(mfn);
pteval_t flags = val & PTE_FLAGS_MASK;
@@ -1721,7 +1721,7 @@ static unsigned long __init m2p(phys_addr_t maddr)
{
phys_addr_t paddr;
- maddr &= PTE_PFN_MASK;
+ maddr &= XEN_PTE_MFN_MASK;
paddr = mfn_to_pfn(maddr >> PAGE_SHIFT) << PAGE_SHIFT;
return paddr;
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
index 92bf5ecb6baf..d9f96cc5d743 100644
--- a/arch/x86/xen/suspend.c
+++ b/arch/x86/xen/suspend.c
@@ -17,6 +17,8 @@
void xen_arch_pre_suspend(void)
{
+ xen_save_time_memory_area();
+
if (xen_pv_domain())
xen_pv_pre_suspend();
}
@@ -27,6 +29,8 @@ void xen_arch_post_suspend(int cancelled)
xen_pv_post_suspend(cancelled);
else
xen_hvm_post_suspend(cancelled);
+
+ xen_restore_time_memory_area();
}
static void xen_vcpu_notify_restore(void *data)
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 80c2a4bdf230..29163c43ebbd 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -75,7 +75,7 @@ static void xen_get_wallclock(struct timespec *now)
static int xen_set_wallclock(const struct timespec *now)
{
- return -1;
+ return -ENODEV;
}
static int xen_pvclock_gtod_notify(struct notifier_block *nb,
@@ -371,8 +371,95 @@ static const struct pv_time_ops xen_time_ops __initconst = {
.steal_clock = xen_steal_clock,
};
+static struct pvclock_vsyscall_time_info *xen_clock __read_mostly;
+
+void xen_save_time_memory_area(void)
+{
+ struct vcpu_register_time_memory_area t;
+ int ret;
+
+ if (!xen_clock)
+ return;
+
+ t.addr.v = NULL;
+
+ ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area, 0, &t);
+ if (ret != 0)
+ pr_notice("Cannot save secondary vcpu_time_info (err %d)",
+ ret);
+ else
+ clear_page(xen_clock);
+}
+
+void xen_restore_time_memory_area(void)
+{
+ struct vcpu_register_time_memory_area t;
+ int ret;
+
+ if (!xen_clock)
+ return;
+
+ t.addr.v = &xen_clock->pvti;
+
+ ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area, 0, &t);
+
+ /*
+ * We don't disable VCLOCK_PVCLOCK entirely if it fails to register the
+ * secondary time info with Xen or if we migrated to a host without the
+ * necessary flags. On both of these cases what happens is either
+ * process seeing a zeroed out pvti or seeing no PVCLOCK_TSC_STABLE_BIT
+ * bit set. Userspace checks the latter and if 0, it discards the data
+ * in pvti and fallbacks to a system call for a reliable timestamp.
+ */
+ if (ret != 0)
+ pr_notice("Cannot restore secondary vcpu_time_info (err %d)",
+ ret);
+}
+
+static void xen_setup_vsyscall_time_info(void)
+{
+ struct vcpu_register_time_memory_area t;
+ struct pvclock_vsyscall_time_info *ti;
+ int ret;
+
+ ti = (struct pvclock_vsyscall_time_info *)get_zeroed_page(GFP_KERNEL);
+ if (!ti)
+ return;
+
+ t.addr.v = &ti->pvti;
+
+ ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area, 0, &t);
+ if (ret) {
+ pr_notice("xen: VCLOCK_PVCLOCK not supported (err %d)\n", ret);
+ free_page((unsigned long)ti);
+ return;
+ }
+
+ /*
+ * If primary time info had this bit set, secondary should too since
+ * it's the same data on both just different memory regions. But we
+ * still check it in case hypervisor is buggy.
+ */
+ if (!(ti->pvti.flags & PVCLOCK_TSC_STABLE_BIT)) {
+ t.addr.v = NULL;
+ ret = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_time_memory_area,
+ 0, &t);
+ if (!ret)
+ free_page((unsigned long)ti);
+
+ pr_notice("xen: VCLOCK_PVCLOCK not supported (tsc unstable)\n");
+ return;
+ }
+
+ xen_clock = ti;
+ pvclock_set_pvti_cpu0_va(xen_clock);
+
+ xen_clocksource.archdata.vclock_mode = VCLOCK_PVCLOCK;
+}
+
static void __init xen_time_init(void)
{
+ struct pvclock_vcpu_time_info *pvti;
int cpu = smp_processor_id();
struct timespec tp;
@@ -396,6 +483,16 @@ static void __init xen_time_init(void)
setup_force_cpu_cap(X86_FEATURE_TSC);
+ /*
+ * We check ahead on the primary time info if this
+ * bit is supported hence speeding up Xen clocksource.
+ */
+ pvti = &__this_cpu_read(xen_vcpu)->time;
+ if (pvti->flags & PVCLOCK_TSC_STABLE_BIT) {
+ pvclock_set_flags(PVCLOCK_TSC_STABLE_BIT);
+ xen_setup_vsyscall_time_info();
+ }
+
xen_setup_runstate_info(cpu);
xen_setup_timer(cpu);
xen_setup_cpu_clockevents();
diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h
index f377e1820c6c..75011b80660f 100644
--- a/arch/x86/xen/xen-ops.h
+++ b/arch/x86/xen/xen-ops.h
@@ -70,6 +70,8 @@ void xen_setup_runstate_info(int cpu);
void xen_teardown_timer(int cpu);
u64 xen_clocksource_read(void);
void xen_setup_cpu_clockevents(void);
+void xen_save_time_memory_area(void);
+void xen_restore_time_memory_area(void);
void __init xen_init_time_ops(void);
void __init xen_hvm_init_time_ops(void);