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authorLe Tan <tamlokveer@gmail.com>2014-08-16 13:55:42 +0800
committerMichael S. Tsirkin <mst@redhat.com>2014-08-28 23:10:22 +0200
commited7b8fbcfb888716c850c8f908f5b5329de46d7c (patch)
tree54fdb4cd840442d09ceb8cff588ab02929745ca3
parentac40aa1540baffb4984c80822da618ebb3180a4d (diff)
intel-iommu: add supports for queued invalidation interface
Add supports for queued invalidation interface, an expended invalidation interface with extended capabilities. Signed-off-by: Le Tan <tamlokveer@gmail.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
-rw-r--r--hw/i386/intel_iommu.c373
-rw-r--r--hw/i386/intel_iommu_internal.h27
2 files changed, 393 insertions, 7 deletions
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 8e67e04d19..60dec4f22a 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -314,6 +314,41 @@ static void vtd_report_dmar_fault(IntelIOMMUState *s, uint16_t source_id,
}
}
+/* Handle Invalidation Queue Errors of queued invalidation interface error
+ * conditions.
+ */
+static void vtd_handle_inv_queue_error(IntelIOMMUState *s)
+{
+ uint32_t fsts_reg = vtd_get_long_raw(s, DMAR_FSTS_REG);
+
+ vtd_set_clear_mask_long(s, DMAR_FSTS_REG, 0, VTD_FSTS_IQE);
+ vtd_generate_fault_event(s, fsts_reg);
+}
+
+/* Set the IWC field and try to generate an invalidation completion interrupt */
+static void vtd_generate_completion_event(IntelIOMMUState *s)
+{
+ VTD_DPRINTF(INV, "completes an invalidation wait command with "
+ "Interrupt Flag");
+ if (vtd_get_long_raw(s, DMAR_ICS_REG) & VTD_ICS_IWC) {
+ VTD_DPRINTF(INV, "there is a previous interrupt condition to be "
+ "serviced by software, "
+ "new invalidation event is not generated");
+ return;
+ }
+ vtd_set_clear_mask_long(s, DMAR_ICS_REG, 0, VTD_ICS_IWC);
+ vtd_set_clear_mask_long(s, DMAR_IECTL_REG, 0, VTD_IECTL_IP);
+ if (vtd_get_long_raw(s, DMAR_IECTL_REG) & VTD_IECTL_IM) {
+ VTD_DPRINTF(INV, "IM filed in IECTL_REG is set, new invalidation "
+ "event is not generated");
+ return;
+ } else {
+ /* Generate the interrupt event */
+ vtd_generate_interrupt(s, DMAR_IEADDR_REG, DMAR_IEDATA_REG);
+ vtd_set_clear_mask_long(s, DMAR_IECTL_REG, VTD_IECTL_IP, 0);
+ }
+}
+
static inline bool vtd_root_entry_present(VTDRootEntry *root)
{
return root->val & VTD_ROOT_ENTRY_P;
@@ -759,6 +794,54 @@ static uint64_t vtd_iotlb_flush(IntelIOMMUState *s, uint64_t val)
return iaig;
}
+static inline bool vtd_queued_inv_enable_check(IntelIOMMUState *s)
+{
+ return s->iq_tail == 0;
+}
+
+static inline bool vtd_queued_inv_disable_check(IntelIOMMUState *s)
+{
+ return s->qi_enabled && (s->iq_tail == s->iq_head) &&
+ (s->iq_last_desc_type == VTD_INV_DESC_WAIT);
+}
+
+static void vtd_handle_gcmd_qie(IntelIOMMUState *s, bool en)
+{
+ uint64_t iqa_val = vtd_get_quad_raw(s, DMAR_IQA_REG);
+
+ VTD_DPRINTF(INV, "Queued Invalidation Enable %s", (en ? "on" : "off"));
+ if (en) {
+ if (vtd_queued_inv_enable_check(s)) {
+ s->iq = iqa_val & VTD_IQA_IQA_MASK;
+ /* 2^(x+8) entries */
+ s->iq_size = 1UL << ((iqa_val & VTD_IQA_QS) + 8);
+ s->qi_enabled = true;
+ VTD_DPRINTF(INV, "DMAR_IQA_REG 0x%"PRIx64, iqa_val);
+ VTD_DPRINTF(INV, "Invalidation Queue addr 0x%"PRIx64 " size %d",
+ s->iq, s->iq_size);
+ /* Ok - report back to driver */
+ vtd_set_clear_mask_long(s, DMAR_GSTS_REG, 0, VTD_GSTS_QIES);
+ } else {
+ VTD_DPRINTF(GENERAL, "error: can't enable Queued Invalidation: "
+ "tail %"PRIu16, s->iq_tail);
+ }
+ } else {
+ if (vtd_queued_inv_disable_check(s)) {
+ /* disable Queued Invalidation */
+ vtd_set_quad_raw(s, DMAR_IQH_REG, 0);
+ s->iq_head = 0;
+ s->qi_enabled = false;
+ /* Ok - report back to driver */
+ vtd_set_clear_mask_long(s, DMAR_GSTS_REG, VTD_GSTS_QIES, 0);
+ } else {
+ VTD_DPRINTF(GENERAL, "error: can't disable Queued Invalidation: "
+ "head %"PRIu16 ", tail %"PRIu16
+ ", last_descriptor %"PRIu8,
+ s->iq_head, s->iq_tail, s->iq_last_desc_type);
+ }
+ }
+}
+
/* Set Root Table Pointer */
static void vtd_handle_gcmd_srtp(IntelIOMMUState *s)
{
@@ -804,6 +887,10 @@ static void vtd_handle_gcmd_write(IntelIOMMUState *s)
/* Set/update the root-table pointer */
vtd_handle_gcmd_srtp(s);
}
+ if (changed & VTD_GCMD_QIE) {
+ /* Queued Invalidation Enable */
+ vtd_handle_gcmd_qie(s, val & VTD_GCMD_QIE);
+ }
}
/* Handle write to Context Command Register */
@@ -814,6 +901,11 @@ static void vtd_handle_ccmd_write(IntelIOMMUState *s)
/* Context-cache invalidation request */
if (val & VTD_CCMD_ICC) {
+ if (s->qi_enabled) {
+ VTD_DPRINTF(GENERAL, "error: Queued Invalidation enabled, "
+ "should not use register-based invalidation");
+ return;
+ }
ret = vtd_context_cache_invalidate(s, val);
/* Invalidation completed. Change something to show */
vtd_set_clear_mask_quad(s, DMAR_CCMD_REG, VTD_CCMD_ICC, 0ULL);
@@ -831,6 +923,11 @@ static void vtd_handle_iotlb_write(IntelIOMMUState *s)
/* IOTLB invalidation request */
if (val & VTD_TLB_IVT) {
+ if (s->qi_enabled) {
+ VTD_DPRINTF(GENERAL, "error: Queued Invalidation enabled, "
+ "should not use register-based invalidation");
+ return;
+ }
ret = vtd_iotlb_flush(s, val);
/* Invalidation completed. Change something to show */
vtd_set_clear_mask_quad(s, DMAR_IOTLB_REG, VTD_TLB_IVT, 0ULL);
@@ -840,6 +937,146 @@ static void vtd_handle_iotlb_write(IntelIOMMUState *s)
}
}
+/* Fetch an Invalidation Descriptor from the Invalidation Queue */
+static bool vtd_get_inv_desc(dma_addr_t base_addr, uint32_t offset,
+ VTDInvDesc *inv_desc)
+{
+ dma_addr_t addr = base_addr + offset * sizeof(*inv_desc);
+ if (dma_memory_read(&address_space_memory, addr, inv_desc,
+ sizeof(*inv_desc))) {
+ VTD_DPRINTF(GENERAL, "error: fail to fetch Invalidation Descriptor "
+ "base_addr 0x%"PRIx64 " offset %"PRIu32, base_addr, offset);
+ inv_desc->lo = 0;
+ inv_desc->hi = 0;
+
+ return false;
+ }
+ inv_desc->lo = le64_to_cpu(inv_desc->lo);
+ inv_desc->hi = le64_to_cpu(inv_desc->hi);
+ return true;
+}
+
+static bool vtd_process_wait_desc(IntelIOMMUState *s, VTDInvDesc *inv_desc)
+{
+ if ((inv_desc->hi & VTD_INV_DESC_WAIT_RSVD_HI) ||
+ (inv_desc->lo & VTD_INV_DESC_WAIT_RSVD_LO)) {
+ VTD_DPRINTF(GENERAL, "error: non-zero reserved field in Invalidation "
+ "Wait Descriptor hi 0x%"PRIx64 " lo 0x%"PRIx64,
+ inv_desc->hi, inv_desc->lo);
+ return false;
+ }
+ if (inv_desc->lo & VTD_INV_DESC_WAIT_SW) {
+ /* Status Write */
+ uint32_t status_data = (uint32_t)(inv_desc->lo >>
+ VTD_INV_DESC_WAIT_DATA_SHIFT);
+
+ assert(!(inv_desc->lo & VTD_INV_DESC_WAIT_IF));
+
+ /* FIXME: need to be masked with HAW? */
+ dma_addr_t status_addr = inv_desc->hi;
+ VTD_DPRINTF(INV, "status data 0x%x, status addr 0x%"PRIx64,
+ status_data, status_addr);
+ status_data = cpu_to_le32(status_data);
+ if (dma_memory_write(&address_space_memory, status_addr, &status_data,
+ sizeof(status_data))) {
+ VTD_DPRINTF(GENERAL, "error: fail to perform a coherent write");
+ return false;
+ }
+ } else if (inv_desc->lo & VTD_INV_DESC_WAIT_IF) {
+ /* Interrupt flag */
+ VTD_DPRINTF(INV, "Invalidation Wait Descriptor interrupt completion");
+ vtd_generate_completion_event(s);
+ } else {
+ VTD_DPRINTF(GENERAL, "error: invalid Invalidation Wait Descriptor: "
+ "hi 0x%"PRIx64 " lo 0x%"PRIx64, inv_desc->hi, inv_desc->lo);
+ return false;
+ }
+ return true;
+}
+
+static bool vtd_process_inv_desc(IntelIOMMUState *s)
+{
+ VTDInvDesc inv_desc;
+ uint8_t desc_type;
+
+ VTD_DPRINTF(INV, "iq head %"PRIu16, s->iq_head);
+ if (!vtd_get_inv_desc(s->iq, s->iq_head, &inv_desc)) {
+ s->iq_last_desc_type = VTD_INV_DESC_NONE;
+ return false;
+ }
+ desc_type = inv_desc.lo & VTD_INV_DESC_TYPE;
+ /* FIXME: should update at first or at last? */
+ s->iq_last_desc_type = desc_type;
+
+ switch (desc_type) {
+ case VTD_INV_DESC_CC:
+ VTD_DPRINTF(INV, "Context-cache Invalidate Descriptor hi 0x%"PRIx64
+ " lo 0x%"PRIx64, inv_desc.hi, inv_desc.lo);
+ break;
+
+ case VTD_INV_DESC_IOTLB:
+ VTD_DPRINTF(INV, "IOTLB Invalidate Descriptor hi 0x%"PRIx64
+ " lo 0x%"PRIx64, inv_desc.hi, inv_desc.lo);
+ break;
+
+ case VTD_INV_DESC_WAIT:
+ VTD_DPRINTF(INV, "Invalidation Wait Descriptor hi 0x%"PRIx64
+ " lo 0x%"PRIx64, inv_desc.hi, inv_desc.lo);
+ if (!vtd_process_wait_desc(s, &inv_desc)) {
+ return false;
+ }
+ break;
+
+ default:
+ VTD_DPRINTF(GENERAL, "error: unkonw Invalidation Descriptor type "
+ "hi 0x%"PRIx64 " lo 0x%"PRIx64 " type %"PRIu8,
+ inv_desc.hi, inv_desc.lo, desc_type);
+ return false;
+ }
+ s->iq_head++;
+ if (s->iq_head == s->iq_size) {
+ s->iq_head = 0;
+ }
+ return true;
+}
+
+/* Try to fetch and process more Invalidation Descriptors */
+static void vtd_fetch_inv_desc(IntelIOMMUState *s)
+{
+ VTD_DPRINTF(INV, "fetch Invalidation Descriptors");
+ if (s->iq_tail >= s->iq_size) {
+ /* Detects an invalid Tail pointer */
+ VTD_DPRINTF(GENERAL, "error: iq_tail is %"PRIu16
+ " while iq_size is %"PRIu16, s->iq_tail, s->iq_size);
+ vtd_handle_inv_queue_error(s);
+ return;
+ }
+ while (s->iq_head != s->iq_tail) {
+ if (!vtd_process_inv_desc(s)) {
+ /* Invalidation Queue Errors */
+ vtd_handle_inv_queue_error(s);
+ break;
+ }
+ /* Must update the IQH_REG in time */
+ vtd_set_quad_raw(s, DMAR_IQH_REG,
+ (((uint64_t)(s->iq_head)) << VTD_IQH_QH_SHIFT) &
+ VTD_IQH_QH_MASK);
+ }
+}
+
+/* Handle write to Invalidation Queue Tail Register */
+static void vtd_handle_iqt_write(IntelIOMMUState *s)
+{
+ uint64_t val = vtd_get_quad_raw(s, DMAR_IQT_REG);
+
+ s->iq_tail = VTD_IQT_QT(val);
+ VTD_DPRINTF(INV, "set iq tail %"PRIu16, s->iq_tail);
+ if (s->qi_enabled && !(vtd_get_long_raw(s, DMAR_FSTS_REG) & VTD_FSTS_IQE)) {
+ /* Process Invalidation Queue here */
+ vtd_fetch_inv_desc(s);
+ }
+}
+
static void vtd_handle_fsts_write(IntelIOMMUState *s)
{
uint32_t fsts_reg = vtd_get_long_raw(s, DMAR_FSTS_REG);
@@ -851,6 +1088,9 @@ static void vtd_handle_fsts_write(IntelIOMMUState *s)
VTD_DPRINTF(FLOG, "all pending interrupt conditions serviced, clear "
"IP field of FECTL_REG");
}
+ /* FIXME: when IQE is Clear, should we try to fetch some Invalidation
+ * Descriptors if there are any when Queued Invalidation is enabled?
+ */
}
static void vtd_handle_fectl_write(IntelIOMMUState *s)
@@ -869,6 +1109,34 @@ static void vtd_handle_fectl_write(IntelIOMMUState *s)
}
}
+static void vtd_handle_ics_write(IntelIOMMUState *s)
+{
+ uint32_t ics_reg = vtd_get_long_raw(s, DMAR_ICS_REG);
+ uint32_t iectl_reg = vtd_get_long_raw(s, DMAR_IECTL_REG);
+
+ if ((iectl_reg & VTD_IECTL_IP) && !(ics_reg & VTD_ICS_IWC)) {
+ vtd_set_clear_mask_long(s, DMAR_IECTL_REG, VTD_IECTL_IP, 0);
+ VTD_DPRINTF(INV, "pending completion interrupt condition serviced, "
+ "clear IP field of IECTL_REG");
+ }
+}
+
+static void vtd_handle_iectl_write(IntelIOMMUState *s)
+{
+ uint32_t iectl_reg;
+ /* FIXME: when software clears the IM field, check the IP field. But do we
+ * need to compare the old value and the new value to conclude that
+ * software clears the IM field? Or just check if the IM field is zero?
+ */
+ iectl_reg = vtd_get_long_raw(s, DMAR_IECTL_REG);
+ if ((iectl_reg & VTD_IECTL_IP) && !(iectl_reg & VTD_IECTL_IM)) {
+ vtd_generate_interrupt(s, DMAR_IEADDR_REG, DMAR_IEDATA_REG);
+ vtd_set_clear_mask_long(s, DMAR_IECTL_REG, VTD_IECTL_IP, 0);
+ VTD_DPRINTF(INV, "IM field is cleared, generate "
+ "invalidation event interrupt");
+ }
+}
+
static uint64_t vtd_mem_read(void *opaque, hwaddr addr, unsigned size)
{
IntelIOMMUState *s = opaque;
@@ -896,6 +1164,19 @@ static uint64_t vtd_mem_read(void *opaque, hwaddr addr, unsigned size)
val = s->root >> 32;
break;
+ /* Invalidation Queue Address Register, 64-bit */
+ case DMAR_IQA_REG:
+ val = s->iq | (vtd_get_quad(s, DMAR_IQA_REG) & VTD_IQA_QS);
+ if (size == 4) {
+ val = val & ((1ULL << 32) - 1);
+ }
+ break;
+
+ case DMAR_IQA_REG_HI:
+ assert(size == 4);
+ val = s->iq >> 32;
+ break;
+
default:
if (size == 4) {
val = vtd_get_long(s, addr);
@@ -1037,6 +1318,86 @@ static void vtd_mem_write(void *opaque, hwaddr addr,
vtd_set_long(s, addr, val);
break;
+ /* Invalidation Queue Tail Register, 64-bit */
+ case DMAR_IQT_REG:
+ VTD_DPRINTF(INV, "DMAR_IQT_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ if (size == 4) {
+ vtd_set_long(s, addr, val);
+ } else {
+ vtd_set_quad(s, addr, val);
+ }
+ vtd_handle_iqt_write(s);
+ break;
+
+ case DMAR_IQT_REG_HI:
+ VTD_DPRINTF(INV, "DMAR_IQT_REG_HI write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ /* 19:63 of IQT_REG is RsvdZ, do nothing here */
+ break;
+
+ /* Invalidation Queue Address Register, 64-bit */
+ case DMAR_IQA_REG:
+ VTD_DPRINTF(INV, "DMAR_IQA_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ if (size == 4) {
+ vtd_set_long(s, addr, val);
+ } else {
+ vtd_set_quad(s, addr, val);
+ }
+ break;
+
+ case DMAR_IQA_REG_HI:
+ VTD_DPRINTF(INV, "DMAR_IQA_REG_HI write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ break;
+
+ /* Invalidation Completion Status Register, 32-bit */
+ case DMAR_ICS_REG:
+ VTD_DPRINTF(INV, "DMAR_ICS_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ vtd_handle_ics_write(s);
+ break;
+
+ /* Invalidation Event Control Register, 32-bit */
+ case DMAR_IECTL_REG:
+ VTD_DPRINTF(INV, "DMAR_IECTL_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ vtd_handle_iectl_write(s);
+ break;
+
+ /* Invalidation Event Data Register, 32-bit */
+ case DMAR_IEDATA_REG:
+ VTD_DPRINTF(INV, "DMAR_IEDATA_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ break;
+
+ /* Invalidation Event Address Register, 32-bit */
+ case DMAR_IEADDR_REG:
+ VTD_DPRINTF(INV, "DMAR_IEADDR_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ break;
+
+ /* Invalidation Event Upper Address Register, 32-bit */
+ case DMAR_IEUADDR_REG:
+ VTD_DPRINTF(INV, "DMAR_IEUADDR_REG write addr 0x%"PRIx64
+ ", size %d, val 0x%"PRIx64, addr, size, val);
+ assert(size == 4);
+ vtd_set_long(s, addr, val);
+ break;
+
/* Fault Recording Registers, 128-bit */
case DMAR_FRCD_REG_0_0:
VTD_DPRINTF(FLOG, "DMAR_FRCD_REG_0_0 write addr 0x%"PRIx64
@@ -1168,7 +1529,7 @@ static void vtd_init(IntelIOMMUState *s)
s->next_frcd_reg = 0;
s->cap = VTD_CAP_FRO | VTD_CAP_NFR | VTD_CAP_ND | VTD_CAP_MGAW |
VTD_CAP_SAGAW;
- s->ecap = VTD_ECAP_IRO;
+ s->ecap = VTD_ECAP_QI | VTD_ECAP_IRO;
/* Define registers with default values and bit semantics */
vtd_define_long(s, DMAR_VER_REG, 0x10UL, 0, 0);
@@ -1198,6 +1559,16 @@ static void vtd_init(IntelIOMMUState *s)
*/
vtd_define_long(s, DMAR_PMEN_REG, 0, 0, 0);
+ vtd_define_quad(s, DMAR_IQH_REG, 0, 0, 0);
+ vtd_define_quad(s, DMAR_IQT_REG, 0, 0x7fff0ULL, 0);
+ vtd_define_quad(s, DMAR_IQA_REG, 0, 0xfffffffffffff007ULL, 0);
+ vtd_define_long(s, DMAR_ICS_REG, 0, 0, 0x1UL);
+ vtd_define_long(s, DMAR_IECTL_REG, 0x80000000UL, 0x80000000UL, 0);
+ vtd_define_long(s, DMAR_IEDATA_REG, 0, 0xffffffffUL, 0);
+ vtd_define_long(s, DMAR_IEADDR_REG, 0, 0xfffffffcUL, 0);
+ /* Treadted as RsvdZ when EIM in ECAP_REG is not supported */
+ vtd_define_long(s, DMAR_IEUADDR_REG, 0, 0, 0);
+
/* IOTLB registers */
vtd_define_quad(s, DMAR_IOTLB_REG, 0, 0Xb003ffff00000000ULL, 0);
vtd_define_quad(s, DMAR_IVA_REG, 0, 0xfffffffffffff07fULL, 0);
diff --git a/hw/i386/intel_iommu_internal.h b/hw/i386/intel_iommu_internal.h
index 7ca034d8e6..cbcc8d1e3b 100644
--- a/hw/i386/intel_iommu_internal.h
+++ b/hw/i386/intel_iommu_internal.h
@@ -255,12 +255,27 @@ typedef enum VTDFaultReason {
VTD_FR_MAX, /* Guard */
} VTDFaultReason;
-/* Masks for Queued Invalidation Descriptor */
-#define VTD_INV_DESC_TYPE 0xf
-#define VTD_INV_DESC_CC 0x1 /* Context-cache Invalidate Desc */
-#define VTD_INV_DESC_IOTLB 0x2
-#define VTD_INV_DESC_WAIT 0x5 /* Invalidation Wait Descriptor */
-#define VTD_INV_DESC_NONE 0 /* Not an Invalidate Descriptor */
+/* Queued Invalidation Descriptor */
+struct VTDInvDesc {
+ uint64_t lo;
+ uint64_t hi;
+};
+typedef struct VTDInvDesc VTDInvDesc;
+
+/* Masks for struct VTDInvDesc */
+#define VTD_INV_DESC_TYPE 0xf
+#define VTD_INV_DESC_CC 0x1 /* Context-cache Invalidate Desc */
+#define VTD_INV_DESC_IOTLB 0x2
+#define VTD_INV_DESC_WAIT 0x5 /* Invalidation Wait Descriptor */
+#define VTD_INV_DESC_NONE 0 /* Not an Invalidate Descriptor */
+
+/* Masks for Invalidation Wait Descriptor*/
+#define VTD_INV_DESC_WAIT_SW (1ULL << 5)
+#define VTD_INV_DESC_WAIT_IF (1ULL << 4)
+#define VTD_INV_DESC_WAIT_FN (1ULL << 6)
+#define VTD_INV_DESC_WAIT_DATA_SHIFT 32
+#define VTD_INV_DESC_WAIT_RSVD_LO 0Xffffff80ULL
+#define VTD_INV_DESC_WAIT_RSVD_HI 3ULL
/* Pagesize of VTD paging structures, including root and context tables */
#define VTD_PAGE_SHIFT 12