[PATCH v2 12/21] x86/xen: split off mmu_hvm.c

From: Vitaly Kuznetsov
Date: Thu Mar 02 2017 - 13:51:01 EST


Move PVHVM related code to mmu_hvm.c.

Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
---
arch/x86/xen/Makefile | 2 +-
arch/x86/xen/mmu.c | 74 ----------------------------------------------
arch/x86/xen/mmu_hvm.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 80 insertions(+), 75 deletions(-)
create mode 100644 arch/x86/xen/mmu_hvm.c

diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
index ebf3522..6a95a8b 100644
--- a/arch/x86/xen/Makefile
+++ b/arch/x86/xen/Makefile
@@ -15,7 +15,7 @@ obj-y := enlighten.o setup.o multicalls.o mmu.o irq.o \
grant-table.o suspend.o platform-pci-unplug.o \
p2m.o apic.o pmu.o enlighten_pv.o

-obj-$(CONFIG_XEN_PVHVM) += enlighten_hvm.o
+obj-$(CONFIG_XEN_PVHVM) += enlighten_hvm.o mmu_hvm.o
obj-$(CONFIG_XEN_PVH) += enlighten_pvh.o

obj-$(CONFIG_EVENT_TRACING) += trace.o
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index f6740b5..4dfcb06 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -2689,80 +2689,6 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order)
}
EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);

-#ifdef CONFIG_XEN_PVHVM
-#ifdef CONFIG_PROC_VMCORE
-/*
- * This function is used in two contexts:
- * - the kdump kernel has to check whether a pfn of the crashed kernel
- * was a ballooned page. vmcore is using this function to decide
- * whether to access a pfn of the crashed kernel.
- * - the kexec kernel has to check whether a pfn was ballooned by the
- * previous kernel. If the pfn is ballooned, handle it properly.
- * Returns 0 if the pfn is not backed by a RAM page, the caller may
- * handle the pfn special in this case.
- */
-static int xen_oldmem_pfn_is_ram(unsigned long pfn)
-{
- struct xen_hvm_get_mem_type a = {
- .domid = DOMID_SELF,
- .pfn = pfn,
- };
- int ram;
-
- if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a))
- return -ENXIO;
-
- switch (a.mem_type) {
- case HVMMEM_mmio_dm:
- ram = 0;
- break;
- case HVMMEM_ram_rw:
- case HVMMEM_ram_ro:
- default:
- ram = 1;
- break;
- }
-
- return ram;
-}
-#endif
-
-static void xen_hvm_exit_mmap(struct mm_struct *mm)
-{
- struct xen_hvm_pagetable_dying a;
- int rc;
-
- a.domid = DOMID_SELF;
- a.gpa = __pa(mm->pgd);
- rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
- WARN_ON_ONCE(rc < 0);
-}
-
-static int is_pagetable_dying_supported(void)
-{
- struct xen_hvm_pagetable_dying a;
- int rc = 0;
-
- a.domid = DOMID_SELF;
- a.gpa = 0x00;
- rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
- if (rc < 0) {
- printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
- return 0;
- }
- return 1;
-}
-
-void __init xen_hvm_init_mmu_ops(void)
-{
- if (is_pagetable_dying_supported())
- pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap;
-#ifdef CONFIG_PROC_VMCORE
- register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram);
-#endif
-}
-#endif
-
#define REMAP_BATCH_SIZE 16

struct remap_data {
diff --git a/arch/x86/xen/mmu_hvm.c b/arch/x86/xen/mmu_hvm.c
new file mode 100644
index 0000000..1c57f1c
--- /dev/null
+++ b/arch/x86/xen/mmu_hvm.c
@@ -0,0 +1,79 @@
+#include <linux/types.h>
+#include <linux/crash_dump.h>
+
+#include <xen/interface/xen.h>
+#include <xen/hvm.h>
+
+#include "mmu.h"
+
+#ifdef CONFIG_PROC_VMCORE
+/*
+ * This function is used in two contexts:
+ * - the kdump kernel has to check whether a pfn of the crashed kernel
+ * was a ballooned page. vmcore is using this function to decide
+ * whether to access a pfn of the crashed kernel.
+ * - the kexec kernel has to check whether a pfn was ballooned by the
+ * previous kernel. If the pfn is ballooned, handle it properly.
+ * Returns 0 if the pfn is not backed by a RAM page, the caller may
+ * handle the pfn special in this case.
+ */
+static int xen_oldmem_pfn_is_ram(unsigned long pfn)
+{
+ struct xen_hvm_get_mem_type a = {
+ .domid = DOMID_SELF,
+ .pfn = pfn,
+ };
+ int ram;
+
+ if (HYPERVISOR_hvm_op(HVMOP_get_mem_type, &a))
+ return -ENXIO;
+
+ switch (a.mem_type) {
+ case HVMMEM_mmio_dm:
+ ram = 0;
+ break;
+ case HVMMEM_ram_rw:
+ case HVMMEM_ram_ro:
+ default:
+ ram = 1;
+ break;
+ }
+
+ return ram;
+}
+#endif
+
+static void xen_hvm_exit_mmap(struct mm_struct *mm)
+{
+ struct xen_hvm_pagetable_dying a;
+ int rc;
+
+ a.domid = DOMID_SELF;
+ a.gpa = __pa(mm->pgd);
+ rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
+ WARN_ON_ONCE(rc < 0);
+}
+
+static int is_pagetable_dying_supported(void)
+{
+ struct xen_hvm_pagetable_dying a;
+ int rc = 0;
+
+ a.domid = DOMID_SELF;
+ a.gpa = 0x00;
+ rc = HYPERVISOR_hvm_op(HVMOP_pagetable_dying, &a);
+ if (rc < 0) {
+ printk(KERN_DEBUG "HVMOP_pagetable_dying not supported\n");
+ return 0;
+ }
+ return 1;
+}
+
+void __init xen_hvm_init_mmu_ops(void)
+{
+ if (is_pagetable_dying_supported())
+ pv_mmu_ops.exit_mmap = xen_hvm_exit_mmap;
+#ifdef CONFIG_PROC_VMCORE
+ register_oldmem_pfn_is_ram(&xen_oldmem_pfn_is_ram);
+#endif
+}
--
2.9.3