introduce XENMEM_reserved_device_memory_map
This is a prerequisite for punching holes into HVM and PVH guests' P2M
to allow passing through devices that are associated with (on VT-d)
RMRRs.
Signed-off-by: Jan Beulich <jbeul...@suse.com>
Acked-by: Kevin Tian <kevin.t...@intel.com>
---
v??: Comment iommu_grdm_t typedef. Comment on the purpose of the new
hypercall in the public header. (Both requested by Tim.)
--- unstable.orig/xen/common/compat/memory.c
+++ unstable/xen/common/compat/memory.c
@@ -17,6 +17,37 @@ CHECK_TYPE(domid);
CHECK_mem_access_op;
CHECK_vmemrange;
+#ifdef HAS_PASSTHROUGH
+struct get_reserved_device_memory {
+ struct compat_reserved_device_memory_map map;
+ unsigned int used_entries;
+};
+
+static int get_reserved_device_memory(xen_pfn_t start,
+ xen_ulong_t nr, void *ctxt)
+{
+ struct get_reserved_device_memory *grdm = ctxt;
+
+ if ( grdm->used_entries < grdm->map.nr_entries )
+ {
+ struct compat_reserved_device_memory rdm = {
+ .start_pfn = start, .nr_pages = nr
+ };
+
+ if ( rdm.start_pfn != start || rdm.nr_pages != nr )
+ return -ERANGE;
+
+ if ( __copy_to_compat_offset(grdm->map.buffer, grdm->used_entries,
+ &rdm, 1) )
+ return -EFAULT;
+ }
+
+ ++grdm->used_entries;
+
+ return 0;
+}
+#endif
+
int compat_memory_op(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) compat)
{
int split, op = cmd & MEMOP_CMD_MASK;
@@ -303,6 +334,29 @@ int compat_memory_op(unsigned int cmd, X
break;
}
+#ifdef HAS_PASSTHROUGH
+ case XENMEM_reserved_device_memory_map:
+ {
+ struct get_reserved_device_memory grdm;
+
+ if ( copy_from_guest(&grdm.map, compat, 1) ||
+ !compat_handle_okay(grdm.map.buffer, grdm.map.nr_entries) )
+ return -EFAULT;
+
+ grdm.used_entries = 0;
+ rc = iommu_get_reserved_device_memory(get_reserved_device_memory,
+ &grdm);
+
+ if ( !rc && grdm.map.nr_entries < grdm.used_entries )
+ rc = -ENOBUFS;
+ grdm.map.nr_entries = grdm.used_entries;
+ if ( __copy_to_guest(compat, &grdm.map, 1) )
+ rc = -EFAULT;
+
+ return rc;
+ }
+#endif
+
default:
return compat_arch_memory_op(cmd, compat);
}
--- unstable.orig/xen/common/memory.c
+++ unstable/xen/common/memory.c
@@ -748,6 +748,34 @@ static int construct_memop_from_reservat
return 0;
}
+#ifdef HAS_PASSTHROUGH
+struct get_reserved_device_memory {
+ struct xen_reserved_device_memory_map map;
+ unsigned int used_entries;
+};
+
+static int get_reserved_device_memory(xen_pfn_t start,
+ xen_ulong_t nr, void *ctxt)
+{
+ struct get_reserved_device_memory *grdm = ctxt;
+
+ if ( grdm->used_entries < grdm->map.nr_entries )
+ {
+ struct xen_reserved_device_memory rdm = {
+ .start_pfn = start, .nr_pages = nr
+ };
+
+ if ( __copy_to_guest_offset(grdm->map.buffer, grdm->used_entries,
+ &rdm, 1) )
+ return -EFAULT;
+ }
+
+ ++grdm->used_entries;
+
+ return 0;
+}
+#endif
+
long do_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
{
struct domain *d;
@@ -1162,6 +1190,32 @@ long do_memory_op(unsigned long cmd, XEN
break;
}
+#ifdef HAS_PASSTHROUGH
+ case XENMEM_reserved_device_memory_map:
+ {
+ struct get_reserved_device_memory grdm;
+
+ if ( unlikely(start_extent) )
+ return -ENOSYS;
+
+ if ( copy_from_guest(&grdm.map, arg, 1) ||
+ !guest_handle_okay(grdm.map.buffer, grdm.map.nr_entries) )
+ return -EFAULT;
+
+ grdm.used_entries = 0;
+ rc = iommu_get_reserved_device_memory(get_reserved_device_memory,
+ &grdm);
+
+ if ( !rc && grdm.map.nr_entries < grdm.used_entries )
+ rc = -ENOBUFS;
+ grdm.map.nr_entries = grdm.used_entries;
+ if ( __copy_to_guest(arg, &grdm.map, 1) )
+ rc = -EFAULT;
+
+ break;
+ }
+#endif
+
default:
rc = arch_memory_op(cmd, arg);
break;
--- unstable.orig/xen/drivers/passthrough/iommu.c
+++ unstable/xen/drivers/passthrough/iommu.c
@@ -344,6 +344,16 @@ void iommu_crash_shutdown(void)
iommu_enabled = iommu_intremap = 0;
}
+int iommu_get_reserved_device_memory(iommu_grdm_t *func, void *ctxt)
+{
+ const struct iommu_ops *ops = iommu_get_ops();
+
+ if ( !iommu_enabled || !ops->get_reserved_device_memory )
+ return 0;
+
+ return ops->get_reserved_device_memory(func, ctxt);
+}
+
bool_t iommu_has_feature(struct domain *d, enum iommu_feature feature)
{
const struct hvm_iommu *hd = domain_hvm_iommu(d);
--- unstable.orig/xen/drivers/passthrough/vtd/dmar.c
+++ unstable/xen/drivers/passthrough/vtd/dmar.c
@@ -893,3 +893,20 @@ int platform_supports_x2apic(void)
unsigned int mask = ACPI_DMAR_INTR_REMAP | ACPI_DMAR_X2APIC_OPT_OUT;
return cpu_has_x2apic && ((dmar_flags & mask) == ACPI_DMAR_INTR_REMAP);
}
+
+int intel_iommu_get_reserved_device_memory(iommu_grdm_t *func, void *ctxt)
+{
+ struct acpi_rmrr_unit *rmrr;
+ int rc = 0;
+
+ list_for_each_entry(rmrr, &acpi_rmrr_units, list)
+ {
+ rc = func(PFN_DOWN(rmrr->base_address),
+ PFN_UP(rmrr->end_address) - PFN_DOWN(rmrr->base_address),
+ ctxt);
+ if ( rc )
+ break;
+ }
+
+ return rc;
+}
--- unstable.orig/xen/drivers/passthrough/vtd/extern.h
+++ unstable/xen/drivers/passthrough/vtd/extern.h
@@ -75,6 +75,7 @@ int domain_context_mapping_one(struct do
u8 bus, u8 devfn, const struct pci_dev *);
int domain_context_unmap_one(struct domain *domain, struct iommu *iommu,
u8 bus, u8 devfn);
+int intel_iommu_get_reserved_device_memory(iommu_grdm_t *func, void *ctxt);
unsigned int io_apic_read_remap_rte(unsigned int apic, unsigned int reg);
void io_apic_write_remap_rte(unsigned int apic,
--- unstable.orig/xen/drivers/passthrough/vtd/iommu.c
+++ unstable/xen/drivers/passthrough/vtd/iommu.c
@@ -2491,6 +2491,7 @@ const struct iommu_ops intel_iommu_ops =
.crash_shutdown = vtd_crash_shutdown,
.iotlb_flush = intel_iommu_iotlb_flush,
.iotlb_flush_all = intel_iommu_iotlb_flush_all,
+ .get_reserved_device_memory = intel_iommu_get_reserved_device_memory,
.dump_p2m_table = vtd_dump_p2m_table,
};
--- unstable.orig/xen/include/public/memory.h
+++ unstable/xen/include/public/memory.h
@@ -573,7 +573,29 @@ struct xen_vnuma_topology_info {
typedef struct xen_vnuma_topology_info xen_vnuma_topology_info_t;
DEFINE_XEN_GUEST_HANDLE(xen_vnuma_topology_info_t);
-/* Next available subop number is 27 */
+/*
+ * With some legacy devices, certain guest-physical addresses cannot safely
+ * be used for other purposes, e.g. to map guest RAM. This hypercall
+ * enumerates those regions so the toolstack can avoid using them.
+ */
+#define XENMEM_reserved_device_memory_map 27
+struct xen_reserved_device_memory {
+ xen_pfn_t start_pfn;
+ xen_ulong_t nr_pages;
+};
+typedef struct xen_reserved_device_memory xen_reserved_device_memory_t;
+DEFINE_XEN_GUEST_HANDLE(xen_reserved_device_memory_t);
+
+struct xen_reserved_device_memory_map {
+ /* IN/OUT */
+ unsigned int nr_entries;
+ /* OUT */
+ XEN_GUEST_HANDLE(xen_reserved_device_memory_t) buffer;
+};
+typedef struct xen_reserved_device_memory_map xen_reserved_device_memory_map_t;
+DEFINE_XEN_GUEST_HANDLE(xen_reserved_device_memory_map_t);
+
+/* Next available subop number is 28 */
#endif /* __XEN_PUBLIC_MEMORY_H__ */
--- unstable.orig/xen/include/xen/iommu.h
+++ unstable/xen/include/xen/iommu.h
@@ -121,6 +121,14 @@ void iommu_dt_domain_destroy(struct doma
struct page_info;
+/*
+ * Any non-zero value returned from callbacks of this type will cause the
+ * function the callback was handed to terminate its iteration. Assigning
+ * meaning of these non-zero values is left to the top level caller /
+ * callback pair.
+ */
+typedef int iommu_grdm_t(xen_pfn_t start, xen_ulong_t nr, void *ctxt);
+
struct iommu_ops {
int (*init)(struct domain *d);
void (*hwdom_init)(struct domain *d);
@@ -152,12 +160,14 @@ struct iommu_ops {
void (*crash_shutdown)(void);
void (*iotlb_flush)(struct domain *d, unsigned long gfn, unsigned int
page_count);
void (*iotlb_flush_all)(struct domain *d);
+ int (*get_reserved_device_memory)(iommu_grdm_t *, void *);
void (*dump_p2m_table)(struct domain *d);
};
void iommu_suspend(void);
void iommu_resume(void);
void iommu_crash_shutdown(void);
+int iommu_get_reserved_device_memory(iommu_grdm_t *, void *);
void iommu_share_p2m_table(struct domain *d);
--- unstable.orig/xen/include/xlat.lst
+++ unstable/xen/include/xlat.lst
@@ -61,9 +61,10 @@
! memory_exchange memory.h
! memory_map memory.h
! memory_reservation memory.h
-? mem_access_op memory.h
+? mem_access_op memory.h
! pod_target memory.h
! remove_from_physmap memory.h
+! reserved_device_memory_map memory.h
? vmemrange memory.h
! vnuma_topology_info memory.h
? physdev_eoi physdev.h
