From: Tiejun Chen <tiejun.chen@intel.com>
To: JBeulich@suse.com, tim@xen.org, konrad.wilk@oracle.com,
kevin.tian@intel.com, yang.z.zhang@intel.com
Cc: xen-devel@lists.xen.org
Subject: [v7][RFC][PATCH 01/13] introduce XENMEM_reserved_device_memory_map
Date: Fri, 24 Oct 2014 15:34:25 +0800 [thread overview]
Message-ID: <1414136077-18599-2-git-send-email-tiejun.chen@intel.com> (raw)
In-Reply-To: <1414136077-18599-1-git-send-email-tiejun.chen@intel.com>
From: Jan Beulich <jbeulich@suse.com>
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 <jbeulich@suse.com>
Signed-off-by: Tiejun Chen <tiejun.chen@intel.com>
---
xen/common/compat/memory.c | 52 ++++++++++++++++++++++++++++++++++++
xen/common/memory.c | 49 +++++++++++++++++++++++++++++++++
xen/drivers/passthrough/iommu.c | 10 +++++++
xen/drivers/passthrough/vtd/dmar.c | 17 ++++++++++++
xen/drivers/passthrough/vtd/extern.h | 1 +
xen/drivers/passthrough/vtd/iommu.c | 1 +
xen/include/public/memory.h | 24 ++++++++++++++++-
xen/include/xen/iommu.h | 4 +++
xen/include/xlat.lst | 3 ++-
9 files changed, 159 insertions(+), 2 deletions(-)
diff --git a/xen/common/compat/memory.c b/xen/common/compat/memory.c
index 43d02bc..01b9f6e 100644
--- a/xen/common/compat/memory.c
+++ b/xen/common/compat/memory.c
@@ -16,6 +16,35 @@ CHECK_TYPE(domid);
CHECK_mem_access_op;
+struct get_reserved_device_memory {
+ struct compat_mem_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_mem_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;
+}
+
int compat_memory_op(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) compat)
{
int split, op = cmd & MEMOP_CMD_MASK;
@@ -273,6 +302,29 @@ int compat_memory_op(unsigned int cmd, XEN_GUEST_HANDLE_PARAM(void) compat)
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);
}
diff --git a/xen/common/memory.c b/xen/common/memory.c
index cc36e39..51a32a8 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -692,6 +692,32 @@ out:
return rc;
}
+struct get_reserved_device_memory {
+ struct xen_mem_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_mem_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;
+}
+
long do_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
{
struct domain *d;
@@ -1101,6 +1127,29 @@ long do_memory_op(unsigned long cmd, XEN_GUEST_HANDLE_PARAM(void) arg)
break;
}
+#ifdef HAS_PASSTHROUGH
+ case XENMEM_reserved_device_memory_map:
+ {
+ struct get_reserved_device_memory grdm;
+
+ 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;
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index cc12735..7c17e8d 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/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);
diff --git a/xen/drivers/passthrough/vtd/dmar.c b/xen/drivers/passthrough/vtd/dmar.c
index 1152c3a..141e735 100644
--- a/xen/drivers/passthrough/vtd/dmar.c
+++ b/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;
+}
diff --git a/xen/drivers/passthrough/vtd/extern.h b/xen/drivers/passthrough/vtd/extern.h
index 5524dba..f9ee9b0 100644
--- a/xen/drivers/passthrough/vtd/extern.h
+++ b/xen/drivers/passthrough/vtd/extern.h
@@ -75,6 +75,7 @@ int domain_context_mapping_one(struct domain *domain, struct iommu *iommu,
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,
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 1c52981..efd3390 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/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,
};
diff --git a/xen/include/public/memory.h b/xen/include/public/memory.h
index f021958..4534215 100644
--- a/xen/include/public/memory.h
+++ b/xen/include/public/memory.h
@@ -573,7 +573,29 @@ struct vnuma_topology_info {
typedef struct vnuma_topology_info vnuma_topology_info_t;
DEFINE_XEN_GUEST_HANDLE(vnuma_topology_info_t);
-/* Next available subop number is 27 */
+/*
+ * For legacy reasons, some devices must be configured with special memory
+ * regions to function correctly. The guest must avoid using any of these
+ * regions.
+ */
+#define XENMEM_reserved_device_memory_map 27
+struct xen_mem_reserved_device_memory {
+ xen_pfn_t start_pfn;
+ xen_ulong_t nr_pages;
+};
+typedef struct xen_mem_reserved_device_memory xen_mem_reserved_device_memory_t;
+DEFINE_XEN_GUEST_HANDLE(xen_mem_reserved_device_memory_t);
+
+struct xen_mem_reserved_device_memory_map {
+ /* IN/OUT */
+ unsigned int nr_entries;
+ /* OUT */
+ XEN_GUEST_HANDLE(xen_mem_reserved_device_memory_t) buffer;
+};
+typedef struct xen_mem_reserved_device_memory_map xen_mem_reserved_device_memory_map_t;
+DEFINE_XEN_GUEST_HANDLE(xen_mem_reserved_device_memory_map_t);
+
+/* Next available subop number is 28 */
#endif /* __XEN_PUBLIC_MEMORY_H__ */
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 8eb764a..409f6f8 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -120,6 +120,8 @@ void iommu_dt_domain_destroy(struct domain *d);
struct page_info;
+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);
@@ -156,12 +158,14 @@ 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);
diff --git a/xen/include/xlat.lst b/xen/include/xlat.lst
index 234b668..2e60a0d 100644
--- a/xen/include/xlat.lst
+++ b/xen/include/xlat.lst
@@ -60,7 +60,8 @@
! memory_exchange memory.h
! memory_map memory.h
! memory_reservation memory.h
-? mem_access_op memory.h
+? mem_access_op memory.h
+! mem_reserved_device_memory_map memory.h
! pod_target memory.h
! remove_from_physmap memory.h
? physdev_eoi physdev.h
--
1.9.1
next prev parent reply other threads:[~2014-10-24 7:34 UTC|newest]
Thread overview: 180+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-24 7:34 [v7][RFC][PATCH 01/13] xen: RMRR fix Tiejun Chen
2014-10-24 7:34 ` Tiejun Chen [this message]
2014-10-24 14:11 ` [v7][RFC][PATCH 01/13] introduce XENMEM_reserved_device_memory_map Jan Beulich
2014-10-27 2:11 ` Chen, Tiejun
2014-10-27 2:18 ` Chen, Tiejun
2014-10-27 9:42 ` Jan Beulich
2014-10-28 2:22 ` Chen, Tiejun
2014-10-27 13:35 ` Julien Grall
2014-10-28 2:35 ` Chen, Tiejun
2014-10-28 10:36 ` Jan Beulich
2014-10-29 0:40 ` Chen, Tiejun
2014-10-29 8:53 ` Jan Beulich
2014-10-30 2:53 ` Chen, Tiejun
2014-10-30 9:10 ` Jan Beulich
2014-10-31 1:03 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 02/13] tools/libxc: introduce hypercall for xc_reserved_device_memory_map Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 03/13] tools/libxc: check if modules space is overlapping with reserved device memory Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 04/13] hvmloader/util: get reserved device memory maps Tiejun Chen
2014-10-24 14:22 ` Jan Beulich
2014-10-27 3:12 ` Chen, Tiejun
2014-10-27 9:45 ` Jan Beulich
2014-10-28 5:21 ` Chen, Tiejun
2014-10-28 9:48 ` Jan Beulich
2014-10-29 6:54 ` Chen, Tiejun
2014-10-29 9:05 ` Jan Beulich
2014-10-30 5:55 ` Chen, Tiejun
2014-10-30 9:13 ` Jan Beulich
2014-10-31 2:20 ` Chen, Tiejun
2014-10-31 8:14 ` Jan Beulich
2014-11-03 2:22 ` Chen, Tiejun
2014-11-03 8:53 ` Jan Beulich
2014-11-03 9:32 ` Chen, Tiejun
2014-11-03 9:45 ` Jan Beulich
2014-11-03 9:55 ` Chen, Tiejun
2014-11-03 10:02 ` Jan Beulich
2014-11-21 6:26 ` Chen, Tiejun
2014-11-21 7:43 ` Tian, Kevin
2014-11-21 7:54 ` Jan Beulich
2014-11-21 8:01 ` Tian, Kevin
2014-11-21 8:54 ` Chen, Tiejun
2014-11-21 9:33 ` Jan Beulich
2014-10-24 14:27 ` Jan Beulich
2014-10-27 5:07 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 05/13] hvmloader/mmio: reconcile guest mmio with reserved device memory Tiejun Chen
2014-10-24 14:42 ` Jan Beulich
2014-10-27 7:12 ` Chen, Tiejun
2014-10-27 9:56 ` Jan Beulich
2014-10-28 7:11 ` Chen, Tiejun
2014-10-28 9:56 ` Jan Beulich
2014-10-29 7:03 ` Chen, Tiejun
2014-10-29 9:08 ` Jan Beulich
2014-10-30 3:18 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 06/13] hvmloader/ram: check if guest memory is out of reserved device memory maps Tiejun Chen
2014-10-24 14:56 ` Jan Beulich
2014-10-27 8:09 ` Chen, Tiejun
2014-10-27 10:17 ` Jan Beulich
2014-10-28 7:47 ` Chen, Tiejun
2014-10-28 10:06 ` Jan Beulich
2014-10-29 7:43 ` Chen, Tiejun
2014-10-29 9:15 ` Jan Beulich
2014-10-30 3:11 ` Chen, Tiejun
2014-10-30 9:20 ` Jan Beulich
2014-10-31 5:41 ` Chen, Tiejun
2014-10-31 6:21 ` Tian, Kevin
2014-10-31 7:02 ` Chen, Tiejun
2014-10-31 8:20 ` Jan Beulich
2014-11-03 5:49 ` Chen, Tiejun
2014-11-03 8:56 ` Jan Beulich
2014-11-03 9:40 ` Chen, Tiejun
2014-11-03 9:51 ` Jan Beulich
2014-11-03 11:32 ` Chen, Tiejun
2014-11-03 11:43 ` Jan Beulich
2014-11-03 11:58 ` Chen, Tiejun
2014-11-03 12:34 ` Jan Beulich
2014-11-04 5:05 ` Chen, Tiejun
2014-11-04 7:54 ` Jan Beulich
2014-11-05 2:59 ` Chen, Tiejun
2014-11-05 17:00 ` Jan Beulich
2014-11-06 9:28 ` Chen, Tiejun
2014-11-06 10:06 ` Jan Beulich
2014-11-07 10:27 ` Chen, Tiejun
2014-11-07 11:08 ` Jan Beulich
2014-11-11 6:32 ` Chen, Tiejun
2014-11-11 7:49 ` Chen, Tiejun
2014-11-11 9:03 ` Jan Beulich
2014-11-11 9:06 ` Jan Beulich
2014-11-11 9:42 ` Chen, Tiejun
2014-11-11 10:07 ` Jan Beulich
2014-11-12 1:36 ` Chen, Tiejun
2014-11-12 8:37 ` Jan Beulich
2014-11-12 8:45 ` Chen, Tiejun
2014-11-12 9:02 ` Jan Beulich
2014-11-12 9:13 ` Chen, Tiejun
2014-11-12 9:56 ` Jan Beulich
2014-11-12 10:18 ` Chen, Tiejun
2014-11-19 8:17 ` Tian, Kevin
2014-11-20 7:45 ` Tian, Kevin
2014-11-20 8:04 ` Jan Beulich
2014-11-20 8:51 ` Tian, Kevin
2014-11-20 14:40 ` Tian, Kevin
2014-11-20 14:46 ` Jan Beulich
2014-11-20 20:11 ` Konrad Rzeszutek Wilk
2014-11-21 0:32 ` Tian, Kevin
2014-11-12 3:05 ` Chen, Tiejun
2014-11-12 8:55 ` Jan Beulich
2014-11-12 10:18 ` Chen, Tiejun
2014-11-12 10:24 ` Jan Beulich
2014-11-12 10:32 ` Chen, Tiejun
2014-11-13 3:09 ` Chen, Tiejun
2014-11-14 2:21 ` Chen, Tiejun
2014-11-14 8:21 ` Jan Beulich
2014-11-17 7:31 ` Chen, Tiejun
2014-11-17 7:57 ` Chen, Tiejun
2014-11-17 10:05 ` Jan Beulich
2014-11-17 11:08 ` Chen, Tiejun
2014-11-17 11:17 ` Jan Beulich
2014-11-17 11:32 ` Chen, Tiejun
2014-11-17 11:51 ` Jan Beulich
2014-11-18 3:08 ` Chen, Tiejun
2014-11-18 8:01 ` Jan Beulich
2014-11-18 8:16 ` Chen, Tiejun
2014-11-18 9:33 ` Jan Beulich
2014-11-19 1:26 ` Chen, Tiejun
2014-11-20 7:31 ` Jan Beulich
2014-11-20 8:12 ` Chen, Tiejun
2014-11-20 8:59 ` Jan Beulich
2014-11-20 10:28 ` Chen, Tiejun
2014-11-11 8:59 ` Jan Beulich
2014-11-11 9:35 ` Chen, Tiejun
2014-11-11 9:42 ` Jan Beulich
2014-11-11 9:51 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 07/13] xen/x86/p2m: introduce p2m_check_reserved_device_memory Tiejun Chen
2014-10-24 15:02 ` Jan Beulich
2014-10-27 8:50 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 08/13] xen/x86/p2m: set p2m_access_n for reserved device memory mapping Tiejun Chen
2014-10-24 15:11 ` Jan Beulich
2014-10-27 9:05 ` Chen, Tiejun
2014-10-27 10:33 ` Jan Beulich
2014-10-28 8:26 ` Chen, Tiejun
2014-10-28 10:12 ` Jan Beulich
2014-10-29 8:20 ` Chen, Tiejun
2014-10-29 9:20 ` Jan Beulich
2014-10-30 7:39 ` Chen, Tiejun
2014-10-30 9:24 ` Jan Beulich
2014-10-31 2:50 ` Chen, Tiejun
2014-10-31 8:25 ` Jan Beulich
2014-11-03 6:20 ` Chen, Tiejun
2014-11-03 9:00 ` Jan Beulich
2014-11-03 9:51 ` Chen, Tiejun
2014-11-03 10:03 ` Jan Beulich
2014-11-03 11:48 ` Chen, Tiejun
2014-11-03 11:53 ` Jan Beulich
2014-11-04 1:35 ` Chen, Tiejun
2014-11-04 8:02 ` Jan Beulich
2014-11-04 10:41 ` Chen, Tiejun
2014-11-04 11:41 ` Jan Beulich
2014-11-04 11:51 ` Chen, Tiejun
2014-10-24 7:34 ` [v7][RFC][PATCH 09/13] xen/x86/ept: handle reserved device memory in ept_handle_violation Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 10/13] xen/x86/p2m: introduce set_identity_p2m_entry Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 11/13] xen:vtd: create RMRR mapping Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 12/13] xen/vtd: re-enable USB device assignment Tiejun Chen
2014-10-24 7:34 ` [v7][RFC][PATCH 13/13] xen/vtd: group assigned device with RMRR Tiejun Chen
2014-10-24 10:52 ` [v7][RFC][PATCH 01/13] xen: RMRR fix Jan Beulich
2014-10-27 2:00 ` Chen, Tiejun
2014-10-27 9:41 ` Jan Beulich
2014-10-28 8:36 ` Chen, Tiejun
2014-10-28 9:34 ` Jan Beulich
2014-10-28 9:39 ` Razvan Cojocaru
2014-10-29 0:51 ` Chen, Tiejun
2014-10-29 0:48 ` Chen, Tiejun
2014-10-29 2:51 ` Chen, Tiejun
2014-10-29 8:45 ` Jan Beulich
2014-10-30 8:21 ` Chen, Tiejun
2014-10-30 9:07 ` Jan Beulich
2014-10-31 3:11 ` Chen, Tiejun
2014-10-29 8:44 ` Jan Beulich
2014-10-30 2:51 ` Chen, Tiejun
2014-10-30 22:15 ` Tim Deegan
2014-10-31 2:53 ` Chen, Tiejun
2014-10-31 9:10 ` Tim Deegan
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