x86/ia64: intel-iommu: move to drivers/iommu/

This should ease finding similarities with different platforms,
with the intention of solving problems once in a generic framework
which everyone can use.

Note: to move intel-iommu.c, the declaration of pci_find_upstream_pcie_bridge()
has to move from drivers/pci/pci.h to include/linux/pci.h. This is handled
in this patch, too.

As suggested, also drop DMAR's EXPERIMENTAL tag while we're at it.

Compile-tested on x86_64.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

7 files changed, 6777 insertions, 0 deletions

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 9246c5b..e2a5f14 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -46,3 +46,52 @@ config AMD_IOMMU_STATS
 	  statistics about whats happening in the driver and exports that
 	  information to userspace via debugfs.
 	  If unsure, say N.
+
+# Intel IOMMU support
+config DMAR
+	bool "Support for DMA Remapping Devices"
+	depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
+	select IOMMU_API
+	help
+	  DMA remapping (DMAR) devices support enables independent address
+	  translations for Direct Memory Access (DMA) from devices.
+	  These DMA remapping devices are reported via ACPI tables
+	  and include PCI device scope covered by these DMA
+	  remapping devices.
+
+config DMAR_DEFAULT_ON
+	def_bool y
+	prompt "Enable DMA Remapping Devices by default"
+	depends on DMAR
+	help
+	  Selecting this option will enable a DMAR device at boot time if
+	  one is found. If this option is not selected, DMAR support can
+	  be enabled by passing intel_iommu=on to the kernel.
+
+config DMAR_BROKEN_GFX_WA
+	bool "Workaround broken graphics drivers (going away soon)"
+	depends on DMAR && BROKEN && X86
+	---help---
+	  Current Graphics drivers tend to use physical address
+	  for DMA and avoid using DMA APIs. Setting this config
+	  option permits the IOMMU driver to set a unity map for
+	  all the OS-visible memory. Hence the driver can continue
+	  to use physical addresses for DMA, at least until this
+	  option is removed in the 2.6.32 kernel.
+
+config DMAR_FLOPPY_WA
+	def_bool y
+	depends on DMAR && X86
+	---help---
+	  Floppy disk drivers are known to bypass DMA API calls
+	  thereby failing to work when IOMMU is enabled. This
+	  workaround will setup a 1:1 mapping for the first
+	  16MiB to make floppy (an ISA device) work.
+
+config INTR_REMAP
+	bool "Support for Interrupt Remapping (EXPERIMENTAL)"
+	depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
+	---help---
+	  Supports Interrupt remapping for IO-APIC and MSI devices.
+	  To use x2apic mode in the CPU's which support x2APIC enhancements or
+	  to support platforms with CPU's having > 8 bit APIC ID, say Y.
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 4237eaf..49e9c0f 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -1,3 +1,5 @@
 obj-$(CONFIG_IOMMU_API) += iommu.o
 obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o msm_iommu_dev.o
 obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o
+obj-$(CONFIG_DMAR) += dmar.o iova.o intel-iommu.o
+obj-$(CONFIG_INTR_REMAP) += dmar.o intr_remapping.o
diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
new file mode 100644
index 0000000..3dc9bef
--- /dev/null
+++ b/drivers/iommu/dmar.c
@@ -0,0 +1,1461 @@
+/*
+ * Copyright (c) 2006, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Copyright (C) 2006-2008 Intel Corporation
+ * Author: Ashok Raj <ashok.raj@intel.com>
+ * Author: Shaohua Li <shaohua.li@intel.com>
+ * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ *
+ * This file implements early detection/parsing of Remapping Devices
+ * reported to OS through BIOS via DMA remapping reporting (DMAR) ACPI
+ * tables.
+ *
+ * These routines are used by both DMA-remapping and Interrupt-remapping
+ */
+
+#include <linux/pci.h>
+#include <linux/dmar.h>
+#include <linux/iova.h>
+#include <linux/intel-iommu.h>
+#include <linux/timer.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/tboot.h>
+#include <linux/dmi.h>
+#include <linux/slab.h>
+#include <asm/iommu_table.h>
+
+#define PREFIX "DMAR: "
+
+/* No locks are needed as DMA remapping hardware unit
+ * list is constructed at boot time and hotplug of
+ * these units are not supported by the architecture.
+ */
+LIST_HEAD(dmar_drhd_units);
+
+static struct acpi_table_header * __initdata dmar_tbl;
+static acpi_size dmar_tbl_size;
+
+static void __init dmar_register_drhd_unit(struct dmar_drhd_unit *drhd)
+{
+	/*
+	 * add INCLUDE_ALL at the tail, so scan the list will find it at
+	 * the very end.
+	 */
+	if (drhd->include_all)
+		list_add_tail(&drhd->list, &dmar_drhd_units);
+	else
+		list_add(&drhd->list, &dmar_drhd_units);
+}
+
+static int __init dmar_parse_one_dev_scope(struct acpi_dmar_device_scope *scope,
+					   struct pci_dev **dev, u16 segment)
+{
+	struct pci_bus *bus;
+	struct pci_dev *pdev = NULL;
+	struct acpi_dmar_pci_path *path;
+	int count;
+
+	bus = pci_find_bus(segment, scope->bus);
+	path = (struct acpi_dmar_pci_path *)(scope + 1);
+	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
+		/ sizeof(struct acpi_dmar_pci_path);
+
+	while (count) {
+		if (pdev)
+			pci_dev_put(pdev);
+		/*
+		 * Some BIOSes list non-exist devices in DMAR table, just
+		 * ignore it
+		 */
+		if (!bus) {
+			printk(KERN_WARNING
+			PREFIX "Device scope bus [%d] not found\n",
+			scope->bus);
+			break;
+		}
+		pdev = pci_get_slot(bus, PCI_DEVFN(path->dev, path->fn));
+		if (!pdev) {
+			printk(KERN_WARNING PREFIX
+			"Device scope device [%04x:%02x:%02x.%02x] not found\n",
+				segment, bus->number, path->dev, path->fn);
+			break;
+		}
+		path ++;
+		count --;
+		bus = pdev->subordinate;
+	}
+	if (!pdev) {
+		printk(KERN_WARNING PREFIX
+		"Device scope device [%04x:%02x:%02x.%02x] not found\n",
+		segment, scope->bus, path->dev, path->fn);
+		*dev = NULL;
+		return 0;
+	}
+	if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && \
+			pdev->subordinate) || (scope->entry_type == \
+			ACPI_DMAR_SCOPE_TYPE_BRIDGE && !pdev->subordinate)) {
+		pci_dev_put(pdev);
+		printk(KERN_WARNING PREFIX
+			"Device scope type does not match for %s\n",
+			 pci_name(pdev));
+		return -EINVAL;
+	}
+	*dev = pdev;
+	return 0;
+}
+
+static int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
+				       struct pci_dev ***devices, u16 segment)
+{
+	struct acpi_dmar_device_scope *scope;
+	void * tmp = start;
+	int index;
+	int ret;
+
+	*cnt = 0;
+	while (start < end) {
+		scope = start;
+		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
+		    scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE)
+			(*cnt)++;
+		else if (scope->entry_type != ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
+			printk(KERN_WARNING PREFIX
+			       "Unsupported device scope\n");
+		}
+		start += scope->length;
+	}
+	if (*cnt == 0)
+		return 0;
+
+	*devices = kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
+	if (!*devices)
+		return -ENOMEM;
+
+	start = tmp;
+	index = 0;
+	while (start < end) {
+		scope = start;
+		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
+		    scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE) {
+			ret = dmar_parse_one_dev_scope(scope,
+				&(*devices)[index], segment);
+			if (ret) {
+				kfree(*devices);
+				return ret;
+			}
+			index ++;
+		}
+		start += scope->length;
+	}
+
+	return 0;
+}
+
+/**
+ * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
+ * structure which uniquely represent one DMA remapping hardware unit
+ * present in the platform
+ */
+static int __init
+dmar_parse_one_drhd(struct acpi_dmar_header *header)
+{
+	struct acpi_dmar_hardware_unit *drhd;
+	struct dmar_drhd_unit *dmaru;
+	int ret = 0;
+
+	drhd = (struct acpi_dmar_hardware_unit *)header;
+	dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
+	if (!dmaru)
+		return -ENOMEM;
+
+	dmaru->hdr = header;
+	dmaru->reg_base_addr = drhd->address;
+	dmaru->segment = drhd->segment;
+	dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
+
+	ret = alloc_iommu(dmaru);
+	if (ret) {
+		kfree(dmaru);
+		return ret;
+	}
+	dmar_register_drhd_unit(dmaru);
+	return 0;
+}
+
+static int __init dmar_parse_dev(struct dmar_drhd_unit *dmaru)
+{
+	struct acpi_dmar_hardware_unit *drhd;
+	int ret = 0;
+
+	drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr;
+
+	if (dmaru->include_all)
+		return 0;
+
+	ret = dmar_parse_dev_scope((void *)(drhd + 1),
+				((void *)drhd) + drhd->header.length,
+				&dmaru->devices_cnt, &dmaru->devices,
+				drhd->segment);
+	if (ret) {
+		list_del(&dmaru->list);
+		kfree(dmaru);
+	}
+	return ret;
+}
+
+#ifdef CONFIG_DMAR
+LIST_HEAD(dmar_rmrr_units);
+
+static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr)
+{
+	list_add(&rmrr->list, &dmar_rmrr_units);
+}
+
+
+static int __init
+dmar_parse_one_rmrr(struct acpi_dmar_header *header)
+{
+	struct acpi_dmar_reserved_memory *rmrr;
+	struct dmar_rmrr_unit *rmrru;
+
+	rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
+	if (!rmrru)
+		return -ENOMEM;
+
+	rmrru->hdr = header;
+	rmrr = (struct acpi_dmar_reserved_memory *)header;
+	rmrru->base_address = rmrr->base_address;
+	rmrru->end_address = rmrr->end_address;
+
+	dmar_register_rmrr_unit(rmrru);
+	return 0;
+}
+
+static int __init
+rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
+{
+	struct acpi_dmar_reserved_memory *rmrr;
+	int ret;
+
+	rmrr = (struct acpi_dmar_reserved_memory *) rmrru->hdr;
+	ret = dmar_parse_dev_scope((void *)(rmrr + 1),
+		((void *)rmrr) + rmrr->header.length,
+		&rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
+
+	if (ret || (rmrru->devices_cnt == 0)) {
+		list_del(&rmrru->list);
+		kfree(rmrru);
+	}
+	return ret;
+}
+
+static LIST_HEAD(dmar_atsr_units);
+
+static int __init dmar_parse_one_atsr(struct acpi_dmar_header *hdr)
+{
+	struct acpi_dmar_atsr *atsr;
+	struct dmar_atsr_unit *atsru;
+
+	atsr = container_of(hdr, struct acpi_dmar_atsr, header);
+	atsru = kzalloc(sizeof(*atsru), GFP_KERNEL);
+	if (!atsru)
+		return -ENOMEM;
+
+	atsru->hdr = hdr;
+	atsru->include_all = atsr->flags & 0x1;
+
+	list_add(&atsru->list, &dmar_atsr_units);
+
+	return 0;
+}
+
+static int __init atsr_parse_dev(struct dmar_atsr_unit *atsru)
+{
+	int rc;
+	struct acpi_dmar_atsr *atsr;
+
+	if (atsru->include_all)
+		return 0;
+
+	atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
+	rc = dmar_parse_dev_scope((void *)(atsr + 1),
+				(void *)atsr + atsr->header.length,
+				&atsru->devices_cnt, &atsru->devices,
+				atsr->segment);
+	if (rc || !atsru->devices_cnt) {
+		list_del(&atsru->list);
+		kfree(atsru);
+	}
+
+	return rc;
+}
+
+int dmar_find_matched_atsr_unit(struct pci_dev *dev)
+{
+	int i;
+	struct pci_bus *bus;
+	struct acpi_dmar_atsr *atsr;
+	struct dmar_atsr_unit *atsru;
+
+	dev = pci_physfn(dev);
+
+	list_for_each_entry(atsru, &dmar_atsr_units, list) {
+		atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
+		if (atsr->segment == pci_domain_nr(dev->bus))
+			goto found;
+	}
+
+	return 0;
+
+found:
+	for (bus = dev->bus; bus; bus = bus->parent) {
+		struct pci_dev *bridge = bus->self;
+
+		if (!bridge || !pci_is_pcie(bridge) ||
+		    bridge->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
+			return 0;
+
+		if (bridge->pcie_type == PCI_EXP_TYPE_ROOT_PORT) {
+			for (i = 0; i < atsru->devices_cnt; i++)
+				if (atsru->devices[i] == bridge)
+					return 1;
+			break;
+		}
+	}
+
+	if (atsru->include_all)
+		return 1;
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_ACPI_NUMA
+static int __init
+dmar_parse_one_rhsa(struct acpi_dmar_header *header)
+{
+	struct acpi_dmar_rhsa *rhsa;
+	struct dmar_drhd_unit *drhd;
+
+	rhsa = (struct acpi_dmar_rhsa *)header;
+	for_each_drhd_unit(drhd) {
+		if (drhd->reg_base_addr == rhsa->base_address) {
+			int node = acpi_map_pxm_to_node(rhsa->proximity_domain);
+
+			if (!node_online(node))
+				node = -1;
+			drhd->iommu->node = node;
+			return 0;
+		}
+	}
+	WARN_TAINT(
+		1, TAINT_FIRMWARE_WORKAROUND,
+		"Your BIOS is broken; RHSA refers to non-existent DMAR unit at %llx\n"
+		"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+		drhd->reg_base_addr,
+		dmi_get_system_info(DMI_BIOS_VENDOR),
+		dmi_get_system_info(DMI_BIOS_VERSION),
+		dmi_get_system_info(DMI_PRODUCT_VERSION));
+
+	return 0;
+}
+#endif
+
+static void __init
+dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
+{
+	struct acpi_dmar_hardware_unit *drhd;
+	struct acpi_dmar_reserved_memory *rmrr;
+	struct acpi_dmar_atsr *atsr;
+	struct acpi_dmar_rhsa *rhsa;
+
+	switch (header->type) {
+	case ACPI_DMAR_TYPE_HARDWARE_UNIT:
+		drhd = container_of(header, struct acpi_dmar_hardware_unit,
+				    header);
+		printk (KERN_INFO PREFIX
+			"DRHD base: %#016Lx flags: %#x\n",
+			(unsigned long long)drhd->address, drhd->flags);
+		break;
+	case ACPI_DMAR_TYPE_RESERVED_MEMORY:
+		rmrr = container_of(header, struct acpi_dmar_reserved_memory,
+				    header);
+		printk (KERN_INFO PREFIX
+			"RMRR base: %#016Lx end: %#016Lx\n",
+			(unsigned long long)rmrr->base_address,
+			(unsigned long long)rmrr->end_address);
+		break;
+	case ACPI_DMAR_TYPE_ATSR:
+		atsr = container_of(header, struct acpi_dmar_atsr, header);
+		printk(KERN_INFO PREFIX "ATSR flags: %#x\n", atsr->flags);
+		break;
+	case ACPI_DMAR_HARDWARE_AFFINITY:
+		rhsa = container_of(header, struct acpi_dmar_rhsa, header);
+		printk(KERN_INFO PREFIX "RHSA base: %#016Lx proximity domain: %#x\n",
+		       (unsigned long long)rhsa->base_address,
+		       rhsa->proximity_domain);
+		break;
+	}
+}
+
+/**
+ * dmar_table_detect - checks to see if the platform supports DMAR devices
+ */
+static int __init dmar_table_detect(void)
+{
+	acpi_status status = AE_OK;
+
+	/* if we could find DMAR table, then there are DMAR devices */
+	status = acpi_get_table_with_size(ACPI_SIG_DMAR, 0,
+				(struct acpi_table_header **)&dmar_tbl,
+				&dmar_tbl_size);
+
+	if (ACPI_SUCCESS(status) && !dmar_tbl) {
+		printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
+		status = AE_NOT_FOUND;
+	}
+
+	return (ACPI_SUCCESS(status) ? 1 : 0);
+}
+
+/**
+ * parse_dmar_table - parses the DMA reporting table
+ */
+static int __init
+parse_dmar_table(void)
+{
+	struct acpi_table_dmar *dmar;
+	struct acpi_dmar_header *entry_header;
+	int ret = 0;
+
+	/*
+	 * Do it again, earlier dmar_tbl mapping could be mapped with
+	 * fixed map.
+	 */
+	dmar_table_detect();
+
+	/*
+	 * ACPI tables may not be DMA protected by tboot, so use DMAR copy
+	 * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
+	 */
+	dmar_tbl = tboot_get_dmar_table(dmar_tbl);
+
+	dmar = (struct acpi_table_dmar *)dmar_tbl;
+	if (!dmar)
+		return -ENODEV;
+
+	if (dmar->width < PAGE_SHIFT - 1) {
+		printk(KERN_WARNING PREFIX "Invalid DMAR haw\n");
+		return -EINVAL;
+	}
+
+	printk (KERN_INFO PREFIX "Host address width %d\n",
+		dmar->width + 1);
+
+	entry_header = (struct acpi_dmar_header *)(dmar + 1);
+	while (((unsigned long)entry_header) <
+			(((unsigned long)dmar) + dmar_tbl->length)) {
+		/* Avoid looping forever on bad ACPI tables */
+		if (entry_header->length == 0) {
+			printk(KERN_WARNING PREFIX
+				"Invalid 0-length structure\n");
+			ret = -EINVAL;
+			break;
+		}
+
+		dmar_table_print_dmar_entry(entry_header);
+
+		switch (entry_header->type) {
+		case ACPI_DMAR_TYPE_HARDWARE_UNIT:
+			ret = dmar_parse_one_drhd(entry_header);
+			break;
+		case ACPI_DMAR_TYPE_RESERVED_MEMORY:
+#ifdef CONFIG_DMAR
+			ret = dmar_parse_one_rmrr(entry_header);
+#endif
+			break;
+		case ACPI_DMAR_TYPE_ATSR:
+#ifdef CONFIG_DMAR
+			ret = dmar_parse_one_atsr(entry_header);
+#endif
+			break;
+		case ACPI_DMAR_HARDWARE_AFFINITY:
+#ifdef CONFIG_ACPI_NUMA
+			ret = dmar_parse_one_rhsa(entry_header);
+#endif
+			break;
+		default:
+			printk(KERN_WARNING PREFIX
+				"Unknown DMAR structure type %d\n",
+				entry_header->type);
+			ret = 0; /* for forward compatibility */
+			break;
+		}
+		if (ret)
+			break;
+
+		entry_header = ((void *)entry_header + entry_header->length);
+	}
+	return ret;
+}
+
+static int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
+			  struct pci_dev *dev)
+{
+	int index;
+
+	while (dev) {
+		for (index = 0; index < cnt; index++)
+			if (dev == devices[index])
+				return 1;
+
+		/* Check our parent */
+		dev = dev->bus->self;
+	}
+
+	return 0;
+}
+
+struct dmar_drhd_unit *
+dmar_find_matched_drhd_unit(struct pci_dev *dev)
+{
+	struct dmar_drhd_unit *dmaru = NULL;
+	struct acpi_dmar_hardware_unit *drhd;
+
+	dev = pci_physfn(dev);
+
+	list_for_each_entry(dmaru, &dmar_drhd_units, list) {
+		drhd = container_of(dmaru->hdr,
+				    struct acpi_dmar_hardware_unit,
+				    header);
+
+		if (dmaru->include_all &&
+		    drhd->segment == pci_domain_nr(dev->bus))
+			return dmaru;
+
+		if (dmar_pci_device_match(dmaru->devices,
+					  dmaru->devices_cnt, dev))
+			return dmaru;
+	}
+
+	return NULL;
+}
+
+int __init dmar_dev_scope_init(void)
+{
+	struct dmar_drhd_unit *drhd, *drhd_n;
+	int ret = -ENODEV;
+
+	list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) {
+		ret = dmar_parse_dev(drhd);
+		if (ret)
+			return ret;
+	}
+
+#ifdef CONFIG_DMAR
+	{
+		struct dmar_rmrr_unit *rmrr, *rmrr_n;
+		struct dmar_atsr_unit *atsr, *atsr_n;
+
+		list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
+			ret = rmrr_parse_dev(rmrr);
+			if (ret)
+				return ret;
+		}
+
+		list_for_each_entry_safe(atsr, atsr_n, &dmar_atsr_units, list) {
+			ret = atsr_parse_dev(atsr);
+			if (ret)
+				return ret;
+		}
+	}
+#endif
+
+	return ret;
+}
+
+
+int __init dmar_table_init(void)
+{
+	static int dmar_table_initialized;
+	int ret;
+
+	if (dmar_table_initialized)
+		return 0;
+
+	dmar_table_initialized = 1;
+
+	ret = parse_dmar_table();
+	if (ret) {
+		if (ret != -ENODEV)
+			printk(KERN_INFO PREFIX "parse DMAR table failure.\n");
+		return ret;
+	}
+
+	if (list_empty(&dmar_drhd_units)) {
+		printk(KERN_INFO PREFIX "No DMAR devices found\n");
+		return -ENODEV;
+	}
+
+#ifdef CONFIG_DMAR
+	if (list_empty(&dmar_rmrr_units))
+		printk(KERN_INFO PREFIX "No RMRR found\n");
+
+	if (list_empty(&dmar_atsr_units))
+		printk(KERN_INFO PREFIX "No ATSR found\n");
+#endif
+
+	return 0;
+}
+
+static void warn_invalid_dmar(u64 addr, const char *message)
+{
+	WARN_TAINT_ONCE(
+		1, TAINT_FIRMWARE_WORKAROUND,
+		"Your BIOS is broken; DMAR reported at address %llx%s!\n"
+		"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+		addr, message,
+		dmi_get_system_info(DMI_BIOS_VENDOR),
+		dmi_get_system_info(DMI_BIOS_VERSION),
+		dmi_get_system_info(DMI_PRODUCT_VERSION));
+}
+
+int __init check_zero_address(void)
+{
+	struct acpi_table_dmar *dmar;
+	struct acpi_dmar_header *entry_header;
+	struct acpi_dmar_hardware_unit *drhd;
+
+	dmar = (struct acpi_table_dmar *)dmar_tbl;
+	entry_header = (struct acpi_dmar_header *)(dmar + 1);
+
+	while (((unsigned long)entry_header) <
+			(((unsigned long)dmar) + dmar_tbl->length)) {
+		/* Avoid looping forever on bad ACPI tables */
+		if (entry_header->length == 0) {
+			printk(KERN_WARNING PREFIX
+				"Invalid 0-length structure\n");
+			return 0;
+		}
+
+		if (entry_header->type == ACPI_DMAR_TYPE_HARDWARE_UNIT) {
+			void __iomem *addr;
+			u64 cap, ecap;
+
+			drhd = (void *)entry_header;
+			if (!drhd->address) {
+				warn_invalid_dmar(0, "");
+				goto failed;
+			}
+
+			addr = early_ioremap(drhd->address, VTD_PAGE_SIZE);
+			if (!addr ) {
+				printk("IOMMU: can't validate: %llx\n", drhd->address);
+				goto failed;
+			}
+			cap = dmar_readq(addr + DMAR_CAP_REG);
+			ecap = dmar_readq(addr + DMAR_ECAP_REG);
+			early_iounmap(addr, VTD_PAGE_SIZE);
+			if (cap == (uint64_t)-1 && ecap == (uint64_t)-1) {
+				warn_invalid_dmar(drhd->address,
+						  " returns all ones");
+				goto failed;
+			}
+		}
+
+		entry_header = ((void *)entry_header + entry_header->length);
+	}
+	return 1;
+
+failed:
+#ifdef CONFIG_DMAR
+	dmar_disabled = 1;
+#endif
+	return 0;
+}
+
+int __init detect_intel_iommu(void)
+{
+	int ret;
+
+	ret = dmar_table_detect();
+	if (ret)
+		ret = check_zero_address();
+	{
+#ifdef CONFIG_INTR_REMAP
+		struct acpi_table_dmar *dmar;
+
+		dmar = (struct acpi_table_dmar *) dmar_tbl;
+		if (ret && cpu_has_x2apic && dmar->flags & 0x1)
+			printk(KERN_INFO
+			       "Queued invalidation will be enabled to support "
+			       "x2apic and Intr-remapping.\n");
+#endif
+#ifdef CONFIG_DMAR
+		if (ret && !no_iommu && !iommu_detected && !dmar_disabled) {
+			iommu_detected = 1;
+			/* Make sure ACS will be enabled */
+			pci_request_acs();
+		}
+#endif
+#ifdef CONFIG_X86
+		if (ret)
+			x86_init.iommu.iommu_init = intel_iommu_init;
+#endif
+	}
+	early_acpi_os_unmap_memory(dmar_tbl, dmar_tbl_size);
+	dmar_tbl = NULL;
+
+	return ret ? 1 : -ENODEV;
+}
+
+
+int alloc_iommu(struct dmar_drhd_unit *drhd)
+{
+	struct intel_iommu *iommu;
+	int map_size;
+	u32 ver;
+	static int iommu_allocated = 0;
+	int agaw = 0;
+	int msagaw = 0;
+
+	if (!drhd->reg_base_addr) {
+		warn_invalid_dmar(0, "");
+		return -EINVAL;
+	}
+
+	iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
+	if (!iommu)
+		return -ENOMEM;
+
+	iommu->seq_id = iommu_allocated++;
+	sprintf (iommu->name, "dmar%d", iommu->seq_id);
+
+	iommu->reg = ioremap(drhd->reg_base_addr, VTD_PAGE_SIZE);
+	if (!iommu->reg) {
+		printk(KERN_ERR "IOMMU: can't map the region\n");
+		goto error;
+	}
+	iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
+	iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
+
+	if (iommu->cap == (uint64_t)-1 && iommu->ecap == (uint64_t)-1) {
+		warn_invalid_dmar(drhd->reg_base_addr, " returns all ones");
+		goto err_unmap;
+	}
+
+#ifdef CONFIG_DMAR
+	agaw = iommu_calculate_agaw(iommu);
+	if (agaw < 0) {
+		printk(KERN_ERR
+		       "Cannot get a valid agaw for iommu (seq_id = %d)\n",
+		       iommu->seq_id);
+		goto err_unmap;
+	}
+	msagaw = iommu_calculate_max_sagaw(iommu);
+	if (msagaw < 0) {
+		printk(KERN_ERR
+			"Cannot get a valid max agaw for iommu (seq_id = %d)\n",
+			iommu->seq_id);
+		goto err_unmap;
+	}
+#endif
+	iommu->agaw = agaw;
+	iommu->msagaw = msagaw;
+
+	iommu->node = -1;
+
+	/* the registers might be more than one page */
+	map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap),
+		cap_max_fault_reg_offset(iommu->cap));
+	map_size = VTD_PAGE_ALIGN(map_size);
+	if (map_size > VTD_PAGE_SIZE) {
+		iounmap(iommu->reg);
+		iommu->reg = ioremap(drhd->reg_base_addr, map_size);
+		if (!iommu->reg) {
+			printk(KERN_ERR "IOMMU: can't map the region\n");
+			goto error;
+		}
+	}
+
+	ver = readl(iommu->reg + DMAR_VER_REG);
+	pr_info("IOMMU %d: reg_base_addr %llx ver %d:%d cap %llx ecap %llx\n",
+		iommu->seq_id,
+		(unsigned long long)drhd->reg_base_addr,
+		DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
+		(unsigned long long)iommu->cap,
+		(unsigned long long)iommu->ecap);
+
+	spin_lock_init(&iommu->register_lock);
+
+	drhd->iommu = iommu;
+	return 0;
+
+ err_unmap:
+	iounmap(iommu->reg);
+ error:
+	kfree(iommu);
+	return -1;
+}
+
+void free_iommu(struct intel_iommu *iommu)
+{
+	if (!iommu)
+		return;
+
+#ifdef CONFIG_DMAR
+	free_dmar_iommu(iommu);
+#endif
+
+	if (iommu->reg)
+		iounmap(iommu->reg);
+	kfree(iommu);
+}
+
+/*
+ * Reclaim all the submitted descriptors which have completed its work.
+ */
+static inline void reclaim_free_desc(struct q_inval *qi)
+{
+	while (qi->desc_status[qi->free_tail] == QI_DONE ||
+	       qi->desc_status[qi->free_tail] == QI_ABORT) {
+		qi->desc_status[qi->free_tail] = QI_FREE;
+		qi->free_tail = (qi->free_tail + 1) % QI_LENGTH;
+		qi->free_cnt++;
+	}
+}
+
+static int qi_check_fault(struct intel_iommu *iommu, int index)
+{
+	u32 fault;
+	int head, tail;
+	struct q_inval *qi = iommu->qi;
+	int wait_index = (index + 1) % QI_LENGTH;
+
+	if (qi->desc_status[wait_index] == QI_ABORT)
+		return -EAGAIN;
+
+	fault = readl(iommu->reg + DMAR_FSTS_REG);
+
+	/*
+	 * If IQE happens, the head points to the descriptor associated
+	 * with the error. No new descriptors are fetched until the IQE
+	 * is cleared.
+	 */
+	if (fault & DMA_FSTS_IQE) {
+		head = readl(iommu->reg + DMAR_IQH_REG);
+		if ((head >> DMAR_IQ_SHIFT) == index) {
+			printk(KERN_ERR "VT-d detected invalid descriptor: "
+				"low=%llx, high=%llx\n",
+				(unsigned long long)qi->desc[index].low,
+				(unsigned long long)qi->desc[index].high);
+			memcpy(&qi->desc[index], &qi->desc[wait_index],
+					sizeof(struct qi_desc));
+			__iommu_flush_cache(iommu, &qi->desc[index],
+					sizeof(struct qi_desc));
+			writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
+			return -EINVAL;
+		}
+	}
+
+	/*
+	 * If ITE happens, all pending wait_desc commands are aborted.
+	 * No new descriptors are fetched until the ITE is cleared.
+	 */
+	if (fault & DMA_FSTS_ITE) {
+		head = readl(iommu->reg + DMAR_IQH_REG);
+		head = ((head >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
+		head |= 1;
+		tail = readl(iommu->reg + DMAR_IQT_REG);
+		tail = ((tail >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
+
+		writel(DMA_FSTS_ITE, iommu->reg + DMAR_FSTS_REG);
+
+		do {
+			if (qi->desc_status[head] == QI_IN_USE)
+				qi->desc_status[head] = QI_ABORT;
+			head = (head - 2 + QI_LENGTH) % QI_LENGTH;
+		} while (head != tail);
+
+		if (qi->desc_status[wait_index] == QI_ABORT)
+			return -EAGAIN;
+	}
+
+	if (fault & DMA_FSTS_ICE)
+		writel(DMA_FSTS_ICE, iommu->reg + DMAR_FSTS_REG);
+
+	return 0;
+}
+
+/*
+ * Submit the queued invalidation descriptor to the remapping
+ * hardware unit and wait for its completion.
+ */
+int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
+{
+	int rc;
+	struct q_inval *qi = iommu->qi;
+	struct qi_desc *hw, wait_desc;
+	int wait_index, index;
+	unsigned long flags;
+
+	if (!qi)
+		return 0;
+
+	hw = qi->desc;
+
+restart:
+	rc = 0;
+
+	spin_lock_irqsave(&qi->q_lock, flags);
+	while (qi->free_cnt < 3) {
+		spin_unlock_irqrestore(&qi->q_lock, flags);
+		cpu_relax();
+		spin_lock_irqsave(&qi->q_lock, flags);
+	}
+
+	index = qi->free_head;
+	wait_index = (index + 1) % QI_LENGTH;
+
+	qi->desc_status[index] = qi->desc_status[wait_index] = QI_IN_USE;
+
+	hw[index] = *desc;
+
+	wait_desc.low = QI_IWD_STATUS_DATA(QI_DONE) |
+			QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
+	wait_desc.high = virt_to_phys(&qi->desc_status[wait_index]);
+
+	hw[wait_index] = wait_desc;
+
+	__iommu_flush_cache(iommu, &hw[index], sizeof(struct qi_desc));
+	__iommu_flush_cache(iommu, &hw[wait_index], sizeof(struct qi_desc));
+
+	qi->free_head = (qi->free_head + 2) % QI_LENGTH;
+	qi->free_cnt -= 2;
+
+	/*
+	 * update the HW tail register indicating the presence of
+	 * new descriptors.
+	 */
+	writel(qi->free_head << DMAR_IQ_SHIFT, iommu->reg + DMAR_IQT_REG);
+
+	while (qi->desc_status[wait_index] != QI_DONE) {
+		/*
+		 * We will leave the interrupts disabled, to prevent interrupt
+		 * context to queue another cmd while a cmd is already submitted
+		 * and waiting for completion on this cpu. This is to avoid
+		 * a deadlock where the interrupt context can wait indefinitely
+		 * for free slots in the queue.
+		 */
+		rc = qi_check_fault(iommu, index);
+		if (rc)
+			break;
+
+		spin_unlock(&qi->q_lock);
+		cpu_relax();
+		spin_lock(&qi->q_lock);
+	}
+
+	qi->desc_status[index] = QI_DONE;
+
+	reclaim_free_desc(qi);
+	spin_unlock_irqrestore(&qi->q_lock, flags);
+
+	if (rc == -EAGAIN)
+		goto restart;
+
+	return rc;
+}
+
+/*
+ * Flush the global interrupt entry cache.
+ */
+void qi_global_iec(struct intel_iommu *iommu)
+{
+	struct qi_desc desc;
+
+	desc.low = QI_IEC_TYPE;
+	desc.high = 0;
+
+	/* should never fail */
+	qi_submit_sync(&desc, iommu);
+}
+
+void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
+		      u64 type)
+{
+	struct qi_desc desc;
+
+	desc.low = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
+			| QI_CC_GRAN(type) | QI_CC_TYPE;
+	desc.high = 0;
+
+	qi_submit_sync(&desc, iommu);
+}
+
+void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
+		    unsigned int size_order, u64 type)
+{
+	u8 dw = 0, dr = 0;
+
+	struct qi_desc desc;
+	int ih = 0;
+
+	if (cap_write_drain(iommu->cap))
+		dw = 1;
+
+	if (cap_read_drain(iommu->cap))
+		dr = 1;
+
+	desc.low = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
+		| QI_IOTLB_GRAN(type) | QI_IOTLB_TYPE;
+	desc.high = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
+		| QI_IOTLB_AM(size_order);
+
+	qi_submit_sync(&desc, iommu);
+}
+
+void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
+			u64 addr, unsigned mask)
+{
+	struct qi_desc desc;
+
+	if (mask) {
+		BUG_ON(addr & ((1 << (VTD_PAGE_SHIFT + mask)) - 1));
+		addr |= (1 << (VTD_PAGE_SHIFT + mask - 1)) - 1;
+		desc.high = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE;
+	} else
+		desc.high = QI_DEV_IOTLB_ADDR(addr);
+
+	if (qdep >= QI_DEV_IOTLB_MAX_INVS)
+		qdep = 0;
+
+	desc.low = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
+		   QI_DIOTLB_TYPE;
+
+	qi_submit_sync(&desc, iommu);
+}
+
+/*
+ * Disable Queued Invalidation interface.
+ */
+void dmar_disable_qi(struct intel_iommu *iommu)
+{
+	unsigned long flags;
+	u32 sts;
+	cycles_t start_time = get_cycles();
+
+	if (!ecap_qis(iommu->ecap))
+		return;
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+
+	sts =  dmar_readq(iommu->reg + DMAR_GSTS_REG);
+	if (!(sts & DMA_GSTS_QIES))
+		goto end;
+
+	/*
+	 * Give a chance to HW to complete the pending invalidation requests.
+	 */
+	while ((readl(iommu->reg + DMAR_IQT_REG) !=
+		readl(iommu->reg + DMAR_IQH_REG)) &&
+		(DMAR_OPERATION_TIMEOUT > (get_cycles() - start_time)))
+		cpu_relax();
+
+	iommu->gcmd &= ~DMA_GCMD_QIE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl,
+		      !(sts & DMA_GSTS_QIES), sts);
+end:
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+/*
+ * Enable queued invalidation.
+ */
+static void __dmar_enable_qi(struct intel_iommu *iommu)
+{
+	u32 sts;
+	unsigned long flags;
+	struct q_inval *qi = iommu->qi;
+
+	qi->free_head = qi->free_tail = 0;
+	qi->free_cnt = QI_LENGTH;
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+
+	/* write zero to the tail reg */
+	writel(0, iommu->reg + DMAR_IQT_REG);
+
+	dmar_writeq(iommu->reg + DMAR_IQA_REG, virt_to_phys(qi->desc));
+
+	iommu->gcmd |= DMA_GCMD_QIE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl, (sts & DMA_GSTS_QIES), sts);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+/*
+ * Enable Queued Invalidation interface. This is a must to support
+ * interrupt-remapping. Also used by DMA-remapping, which replaces
+ * register based IOTLB invalidation.
+ */
+int dmar_enable_qi(struct intel_iommu *iommu)
+{
+	struct q_inval *qi;
+	struct page *desc_page;
+
+	if (!ecap_qis(iommu->ecap))
+		return -ENOENT;
+
+	/*
+	 * queued invalidation is already setup and enabled.
+	 */
+	if (iommu->qi)
+		return 0;
+
+	iommu->qi = kmalloc(sizeof(*qi), GFP_ATOMIC);
+	if (!iommu->qi)
+		return -ENOMEM;
+
+	qi = iommu->qi;
+
+
+	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO, 0);
+	if (!desc_page) {
+		kfree(qi);
+		iommu->qi = 0;
+		return -ENOMEM;
+	}
+
+	qi->desc = page_address(desc_page);
+
+	qi->desc_status = kmalloc(QI_LENGTH * sizeof(int), GFP_ATOMIC);
+	if (!qi->desc_status) {
+		free_page((unsigned long) qi->desc);
+		kfree(qi);
+		iommu->qi = 0;
+		return -ENOMEM;
+	}
+
+	qi->free_head = qi->free_tail = 0;
+	qi->free_cnt = QI_LENGTH;
+
+	spin_lock_init(&qi->q_lock);
+
+	__dmar_enable_qi(iommu);
+
+	return 0;
+}
+
+/* iommu interrupt handling. Most stuff are MSI-like. */
+
+enum faulttype {
+	DMA_REMAP,
+	INTR_REMAP,
+	UNKNOWN,
+};
+
+static const char *dma_remap_fault_reasons[] =
+{
+	"Software",
+	"Present bit in root entry is clear",
+	"Present bit in context entry is clear",
+	"Invalid context entry",
+	"Access beyond MGAW",
+	"PTE Write access is not set",
+	"PTE Read access is not set",
+	"Next page table ptr is invalid",
+	"Root table address invalid",
+	"Context table ptr is invalid",
+	"non-zero reserved fields in RTP",
+	"non-zero reserved fields in CTP",
+	"non-zero reserved fields in PTE",
+};
+
+static const char *intr_remap_fault_reasons[] =
+{
+	"Detected reserved fields in the decoded interrupt-remapped request",
+	"Interrupt index exceeded the interrupt-remapping table size",
+	"Present field in the IRTE entry is clear",
+	"Error accessing interrupt-remapping table pointed by IRTA_REG",
+	"Detected reserved fields in the IRTE entry",
+	"Blocked a compatibility format interrupt request",
+	"Blocked an interrupt request due to source-id verification failure",
+};
+
+#define MAX_FAULT_REASON_IDX 	(ARRAY_SIZE(fault_reason_strings) - 1)
+
+const char *dmar_get_fault_reason(u8 fault_reason, int *fault_type)
+{
+	if (fault_reason >= 0x20 && (fault_reason <= 0x20 +
+				     ARRAY_SIZE(intr_remap_fault_reasons))) {
+		*fault_type = INTR_REMAP;
+		return intr_remap_fault_reasons[fault_reason - 0x20];
+	} else if (fault_reason < ARRAY_SIZE(dma_remap_fault_reasons)) {
+		*fault_type = DMA_REMAP;
+		return dma_remap_fault_reasons[fault_reason];
+	} else {
+		*fault_type = UNKNOWN;
+		return "Unknown";
+	}
+}
+
+void dmar_msi_unmask(struct irq_data *data)
+{
+	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
+	unsigned long flag;
+
+	/* unmask it */
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	writel(0, iommu->reg + DMAR_FECTL_REG);
+	/* Read a reg to force flush the post write */
+	readl(iommu->reg + DMAR_FECTL_REG);
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+void dmar_msi_mask(struct irq_data *data)
+{
+	unsigned long flag;
+	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
+
+	/* mask it */
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	writel(DMA_FECTL_IM, iommu->reg + DMAR_FECTL_REG);
+	/* Read a reg to force flush the post write */
+	readl(iommu->reg + DMAR_FECTL_REG);
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+void dmar_msi_write(int irq, struct msi_msg *msg)
+{
+	struct intel_iommu *iommu = irq_get_handler_data(irq);
+	unsigned long flag;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	writel(msg->data, iommu->reg + DMAR_FEDATA_REG);
+	writel(msg->address_lo, iommu->reg + DMAR_FEADDR_REG);
+	writel(msg->address_hi, iommu->reg + DMAR_FEUADDR_REG);
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+void dmar_msi_read(int irq, struct msi_msg *msg)
+{
+	struct intel_iommu *iommu = irq_get_handler_data(irq);
+	unsigned long flag;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	msg->data = readl(iommu->reg + DMAR_FEDATA_REG);
+	msg->address_lo = readl(iommu->reg + DMAR_FEADDR_REG);
+	msg->address_hi = readl(iommu->reg + DMAR_FEUADDR_REG);
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
+		u8 fault_reason, u16 source_id, unsigned long long addr)
+{
+	const char *reason;
+	int fault_type;
+
+	reason = dmar_get_fault_reason(fault_reason, &fault_type);
+
+	if (fault_type == INTR_REMAP)
+		printk(KERN_ERR "INTR-REMAP: Request device [[%02x:%02x.%d] "
+		       "fault index %llx\n"
+			"INTR-REMAP:[fault reason %02d] %s\n",
+			(source_id >> 8), PCI_SLOT(source_id & 0xFF),
+			PCI_FUNC(source_id & 0xFF), addr >> 48,
+			fault_reason, reason);
+	else
+		printk(KERN_ERR
+		       "DMAR:[%s] Request device [%02x:%02x.%d] "
+		       "fault addr %llx \n"
+		       "DMAR:[fault reason %02d] %s\n",
+		       (type ? "DMA Read" : "DMA Write"),
+		       (source_id >> 8), PCI_SLOT(source_id & 0xFF),
+		       PCI_FUNC(source_id & 0xFF), addr, fault_reason, reason);
+	return 0;
+}
+
+#define PRIMARY_FAULT_REG_LEN (16)
+irqreturn_t dmar_fault(int irq, void *dev_id)
+{
+	struct intel_iommu *iommu = dev_id;
+	int reg, fault_index;
+	u32 fault_status;
+	unsigned long flag;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	fault_status = readl(iommu->reg + DMAR_FSTS_REG);
+	if (fault_status)
+		printk(KERN_ERR "DRHD: handling fault status reg %x\n",
+		       fault_status);
+
+	/* TBD: ignore advanced fault log currently */
+	if (!(fault_status & DMA_FSTS_PPF))
+		goto clear_rest;
+
+	fault_index = dma_fsts_fault_record_index(fault_status);
+	reg = cap_fault_reg_offset(iommu->cap);
+	while (1) {
+		u8 fault_reason;
+		u16 source_id;
+		u64 guest_addr;
+		int type;
+		u32 data;
+
+		/* highest 32 bits */
+		data = readl(iommu->reg + reg +
+				fault_index * PRIMARY_FAULT_REG_LEN + 12);
+		if (!(data & DMA_FRCD_F))
+			break;
+
+		fault_reason = dma_frcd_fault_reason(data);
+		type = dma_frcd_type(data);
+
+		data = readl(iommu->reg + reg +
+				fault_index * PRIMARY_FAULT_REG_LEN + 8);
+		source_id = dma_frcd_source_id(data);
+
+		guest_addr = dmar_readq(iommu->reg + reg +
+				fault_index * PRIMARY_FAULT_REG_LEN);
+		guest_addr = dma_frcd_page_addr(guest_addr);
+		/* clear the fault */
+		writel(DMA_FRCD_F, iommu->reg + reg +
+			fault_index * PRIMARY_FAULT_REG_LEN + 12);
+
+		spin_unlock_irqrestore(&iommu->register_lock, flag);
+
+		dmar_fault_do_one(iommu, type, fault_reason,
+				source_id, guest_addr);
+
+		fault_index++;
+		if (fault_index >= cap_num_fault_regs(iommu->cap))
+			fault_index = 0;
+		spin_lock_irqsave(&iommu->register_lock, flag);
+	}
+clear_rest:
+	/* clear all the other faults */
+	fault_status = readl(iommu->reg + DMAR_FSTS_REG);
+	writel(fault_status, iommu->reg + DMAR_FSTS_REG);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+	return IRQ_HANDLED;
+}
+
+int dmar_set_interrupt(struct intel_iommu *iommu)
+{
+	int irq, ret;
+
+	/*
+	 * Check if the fault interrupt is already initialized.
+	 */
+	if (iommu->irq)
+		return 0;
+
+	irq = create_irq();
+	if (!irq) {
+		printk(KERN_ERR "IOMMU: no free vectors\n");
+		return -EINVAL;
+	}
+
+	irq_set_handler_data(irq, iommu);
+	iommu->irq = irq;
+
+	ret = arch_setup_dmar_msi(irq);
+	if (ret) {
+		irq_set_handler_data(irq, NULL);
+		iommu->irq = 0;
+		destroy_irq(irq);
+		return ret;
+	}
+
+	ret = request_irq(irq, dmar_fault, 0, iommu->name, iommu);
+	if (ret)
+		printk(KERN_ERR "IOMMU: can't request irq\n");
+	return ret;
+}
+
+int __init enable_drhd_fault_handling(void)
+{
+	struct dmar_drhd_unit *drhd;
+
+	/*
+	 * Enable fault control interrupt.
+	 */
+	for_each_drhd_unit(drhd) {
+		int ret;
+		struct intel_iommu *iommu = drhd->iommu;
+		ret = dmar_set_interrupt(iommu);
+
+		if (ret) {
+			printk(KERN_ERR "DRHD %Lx: failed to enable fault, "
+			       " interrupt, ret %d\n",
+			       (unsigned long long)drhd->reg_base_addr, ret);
+			return -1;
+		}
+
+		/*
+		 * Clear any previous faults.
+		 */
+		dmar_fault(iommu->irq, iommu);
+	}
+
+	return 0;
+}
+
+/*
+ * Re-enable Queued Invalidation interface.
+ */
+int dmar_reenable_qi(struct intel_iommu *iommu)
+{
+	if (!ecap_qis(iommu->ecap))
+		return -ENOENT;
+
+	if (!iommu->qi)
+		return -ENOENT;
+
+	/*
+	 * First disable queued invalidation.
+	 */
+	dmar_disable_qi(iommu);
+	/*
+	 * Then enable queued invalidation again. Since there is no pending
+	 * invalidation requests now, it's safe to re-enable queued
+	 * invalidation.
+	 */
+	__dmar_enable_qi(iommu);
+
+	return 0;
+}
+
+/*
+ * Check interrupt remapping support in DMAR table description.
+ */
+int __init dmar_ir_support(void)
+{
+	struct acpi_table_dmar *dmar;
+	dmar = (struct acpi_table_dmar *)dmar_tbl;
+	if (!dmar)
+		return 0;
+	return dmar->flags & 0x1;
+}
+IOMMU_INIT_POST(detect_intel_iommu);
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
new file mode 100644
index 0000000..c621c98
--- /dev/null
+++ b/drivers/iommu/intel-iommu.c
@@ -0,0 +1,4016 @@
+/*
+ * Copyright (c) 2006, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Copyright (C) 2006-2008 Intel Corporation
+ * Author: Ashok Raj <ashok.raj@intel.com>
+ * Author: Shaohua Li <shaohua.li@intel.com>
+ * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * Author: Fenghua Yu <fenghua.yu@intel.com>
+ */
+
+#include <linux/init.h>
+#include <linux/bitmap.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/dmar.h>
+#include <linux/dma-mapping.h>
+#include <linux/mempool.h>
+#include <linux/timer.h>
+#include <linux/iova.h>
+#include <linux/iommu.h>
+#include <linux/intel-iommu.h>
+#include <linux/syscore_ops.h>
+#include <linux/tboot.h>
+#include <linux/dmi.h>
+#include <linux/pci-ats.h>
+#include <asm/cacheflush.h>
+#include <asm/iommu.h>
+
+#define ROOT_SIZE		VTD_PAGE_SIZE
+#define CONTEXT_SIZE		VTD_PAGE_SIZE
+
+#define IS_BRIDGE_HOST_DEVICE(pdev) \
+			    ((pdev->class >> 8) == PCI_CLASS_BRIDGE_HOST)
+#define IS_GFX_DEVICE(pdev) ((pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
+#define IS_ISA_DEVICE(pdev) ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA)
+#define IS_AZALIA(pdev) ((pdev)->vendor == 0x8086 && (pdev)->device == 0x3a3e)
+
+#define IOAPIC_RANGE_START	(0xfee00000)
+#define IOAPIC_RANGE_END	(0xfeefffff)
+#define IOVA_START_ADDR		(0x1000)
+
+#define DEFAULT_DOMAIN_ADDRESS_WIDTH 48
+
+#define MAX_AGAW_WIDTH 64
+
+#define __DOMAIN_MAX_PFN(gaw)  ((((uint64_t)1) << (gaw-VTD_PAGE_SHIFT)) - 1)
+#define __DOMAIN_MAX_ADDR(gaw) ((((uint64_t)1) << gaw) - 1)
+
+/* We limit DOMAIN_MAX_PFN to fit in an unsigned long, and DOMAIN_MAX_ADDR
+   to match. That way, we can use 'unsigned long' for PFNs with impunity. */
+#define DOMAIN_MAX_PFN(gaw)	((unsigned long) min_t(uint64_t, \
+				__DOMAIN_MAX_PFN(gaw), (unsigned long)-1))
+#define DOMAIN_MAX_ADDR(gaw)	(((uint64_t)__DOMAIN_MAX_PFN(gaw)) << VTD_PAGE_SHIFT)
+
+#define IOVA_PFN(addr)		((addr) >> PAGE_SHIFT)
+#define DMA_32BIT_PFN		IOVA_PFN(DMA_BIT_MASK(32))
+#define DMA_64BIT_PFN		IOVA_PFN(DMA_BIT_MASK(64))
+
+/* page table handling */
+#define LEVEL_STRIDE		(9)
+#define LEVEL_MASK		(((u64)1 << LEVEL_STRIDE) - 1)
+
+static inline int agaw_to_level(int agaw)
+{
+	return agaw + 2;
+}
+
+static inline int agaw_to_width(int agaw)
+{
+	return 30 + agaw * LEVEL_STRIDE;
+}
+
+static inline int width_to_agaw(int width)
+{
+	return (width - 30) / LEVEL_STRIDE;
+}
+
+static inline unsigned int level_to_offset_bits(int level)
+{
+	return (level - 1) * LEVEL_STRIDE;
+}
+
+static inline int pfn_level_offset(unsigned long pfn, int level)
+{
+	return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK;
+}
+
+static inline unsigned long level_mask(int level)
+{
+	return -1UL << level_to_offset_bits(level);
+}
+
+static inline unsigned long level_size(int level)
+{
+	return 1UL << level_to_offset_bits(level);
+}
+
+static inline unsigned long align_to_level(unsigned long pfn, int level)
+{
+	return (pfn + level_size(level) - 1) & level_mask(level);
+}
+
+static inline unsigned long lvl_to_nr_pages(unsigned int lvl)
+{
+	return  1 << ((lvl - 1) * LEVEL_STRIDE);
+}
+
+/* VT-d pages must always be _smaller_ than MM pages. Otherwise things
+   are never going to work. */
+static inline unsigned long dma_to_mm_pfn(unsigned long dma_pfn)
+{
+	return dma_pfn >> (PAGE_SHIFT - VTD_PAGE_SHIFT);
+}
+
+static inline unsigned long mm_to_dma_pfn(unsigned long mm_pfn)
+{
+	return mm_pfn << (PAGE_SHIFT - VTD_PAGE_SHIFT);
+}
+static inline unsigned long page_to_dma_pfn(struct page *pg)
+{
+	return mm_to_dma_pfn(page_to_pfn(pg));
+}
+static inline unsigned long virt_to_dma_pfn(void *p)
+{
+	return page_to_dma_pfn(virt_to_page(p));
+}
+
+/* global iommu list, set NULL for ignored DMAR units */
+static struct intel_iommu **g_iommus;
+
+static void __init check_tylersburg_isoch(void);
+static int rwbf_quirk;
+
+/*
+ * set to 1 to panic kernel if can't successfully enable VT-d
+ * (used when kernel is launched w/ TXT)
+ */
+static int force_on = 0;
+
+/*
+ * 0: Present
+ * 1-11: Reserved
+ * 12-63: Context Ptr (12 - (haw-1))
+ * 64-127: Reserved
+ */
+struct root_entry {
+	u64	val;
+	u64	rsvd1;
+};
+#define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry))
+static inline bool root_present(struct root_entry *root)
+{
+	return (root->val & 1);
+}
+static inline void set_root_present(struct root_entry *root)
+{
+	root->val |= 1;
+}
+static inline void set_root_value(struct root_entry *root, unsigned long value)
+{
+	root->val |= value & VTD_PAGE_MASK;
+}
+
+static inline struct context_entry *
+get_context_addr_from_root(struct root_entry *root)
+{
+	return (struct context_entry *)
+		(root_present(root)?phys_to_virt(
+		root->val & VTD_PAGE_MASK) :
+		NULL);
+}
+
+/*
+ * low 64 bits:
+ * 0: present
+ * 1: fault processing disable
+ * 2-3: translation type
+ * 12-63: address space root
+ * high 64 bits:
+ * 0-2: address width
+ * 3-6: aval
+ * 8-23: domain id
+ */
+struct context_entry {
+	u64 lo;
+	u64 hi;
+};
+
+static inline bool context_present(struct context_entry *context)
+{
+	return (context->lo & 1);
+}
+static inline void context_set_present(struct context_entry *context)
+{
+	context->lo |= 1;
+}
+
+static inline void context_set_fault_enable(struct context_entry *context)
+{
+	context->lo &= (((u64)-1) << 2) | 1;
+}
+
+static inline void context_set_translation_type(struct context_entry *context,
+						unsigned long value)
+{
+	context->lo &= (((u64)-1) << 4) | 3;
+	context->lo |= (value & 3) << 2;
+}
+
+static inline void context_set_address_root(struct context_entry *context,
+					    unsigned long value)
+{
+	context->lo |= value & VTD_PAGE_MASK;
+}
+
+static inline void context_set_address_width(struct context_entry *context,
+					     unsigned long value)
+{
+	context->hi |= value & 7;
+}
+
+static inline void context_set_domain_id(struct context_entry *context,
+					 unsigned long value)
+{
+	context->hi |= (value & ((1 << 16) - 1)) << 8;
+}
+
+static inline void context_clear_entry(struct context_entry *context)
+{
+	context->lo = 0;
+	context->hi = 0;
+}
+
+/*
+ * 0: readable
+ * 1: writable
+ * 2-6: reserved
+ * 7: super page
+ * 8-10: available
+ * 11: snoop behavior
+ * 12-63: Host physcial address
+ */
+struct dma_pte {
+	u64 val;
+};
+
+static inline void dma_clear_pte(struct dma_pte *pte)
+{
+	pte->val = 0;
+}
+
+static inline void dma_set_pte_readable(struct dma_pte *pte)
+{
+	pte->val |= DMA_PTE_READ;
+}
+
+static inline void dma_set_pte_writable(struct dma_pte *pte)
+{
+	pte->val |= DMA_PTE_WRITE;
+}
+
+static inline void dma_set_pte_snp(struct dma_pte *pte)
+{
+	pte->val |= DMA_PTE_SNP;
+}
+
+static inline void dma_set_pte_prot(struct dma_pte *pte, unsigned long prot)
+{
+	pte->val = (pte->val & ~3) | (prot & 3);
+}
+
+static inline u64 dma_pte_addr(struct dma_pte *pte)
+{
+#ifdef CONFIG_64BIT
+	return pte->val & VTD_PAGE_MASK;
+#else
+	/* Must have a full atomic 64-bit read */
+	return  __cmpxchg64(&pte->val, 0ULL, 0ULL) & VTD_PAGE_MASK;
+#endif
+}
+
+static inline void dma_set_pte_pfn(struct dma_pte *pte, unsigned long pfn)
+{
+	pte->val |= (uint64_t)pfn << VTD_PAGE_SHIFT;
+}
+
+static inline bool dma_pte_present(struct dma_pte *pte)
+{
+	return (pte->val & 3) != 0;
+}
+
+static inline int first_pte_in_page(struct dma_pte *pte)
+{
+	return !((unsigned long)pte & ~VTD_PAGE_MASK);
+}
+
+/*
+ * This domain is a statically identity mapping domain.
+ *	1. This domain creats a static 1:1 mapping to all usable memory.
+ * 	2. It maps to each iommu if successful.
+ *	3. Each iommu mapps to this domain if successful.
+ */
+static struct dmar_domain *si_domain;
+static int hw_pass_through = 1;
+
+/* devices under the same p2p bridge are owned in one domain */
+#define DOMAIN_FLAG_P2P_MULTIPLE_DEVICES (1 << 0)
+
+/* domain represents a virtual machine, more than one devices
+ * across iommus may be owned in one domain, e.g. kvm guest.
+ */
+#define DOMAIN_FLAG_VIRTUAL_MACHINE	(1 << 1)
+
+/* si_domain contains mulitple devices */
+#define DOMAIN_FLAG_STATIC_IDENTITY	(1 << 2)
+
+struct dmar_domain {
+	int	id;			/* domain id */
+	int	nid;			/* node id */
+	unsigned long iommu_bmp;	/* bitmap of iommus this domain uses*/
+
+	struct list_head devices; 	/* all devices' list */
+	struct iova_domain iovad;	/* iova's that belong to this domain */
+
+	struct dma_pte	*pgd;		/* virtual address */
+	int		gaw;		/* max guest address width */
+
+	/* adjusted guest address width, 0 is level 2 30-bit */
+	int		agaw;
+
+	int		flags;		/* flags to find out type of domain */
+
+	int		iommu_coherency;/* indicate coherency of iommu access */
+	int		iommu_snooping; /* indicate snooping control feature*/
+	int		iommu_count;	/* reference count of iommu */
+	int		iommu_superpage;/* Level of superpages supported:
+					   0 == 4KiB (no superpages), 1 == 2MiB,
+					   2 == 1GiB, 3 == 512GiB, 4 == 1TiB */
+	spinlock_t	iommu_lock;	/* protect iommu set in domain */
+	u64		max_addr;	/* maximum mapped address */
+};
+
+/* PCI domain-device relationship */
+struct device_domain_info {
+	struct list_head link;	/* link to domain siblings */
+	struct list_head global; /* link to global list */
+	int segment;		/* PCI domain */
+	u8 bus;			/* PCI bus number */
+	u8 devfn;		/* PCI devfn number */
+	struct pci_dev *dev; /* it's NULL for PCIe-to-PCI bridge */
+	struct intel_iommu *iommu; /* IOMMU used by this device */
+	struct dmar_domain *domain; /* pointer to domain */
+};
+
+static void flush_unmaps_timeout(unsigned long data);
+
+DEFINE_TIMER(unmap_timer,  flush_unmaps_timeout, 0, 0);
+
+#define HIGH_WATER_MARK 250
+struct deferred_flush_tables {
+	int next;
+	struct iova *iova[HIGH_WATER_MARK];
+	struct dmar_domain *domain[HIGH_WATER_MARK];
+};
+
+static struct deferred_flush_tables *deferred_flush;
+
+/* bitmap for indexing intel_iommus */
+static int g_num_of_iommus;
+
+static DEFINE_SPINLOCK(async_umap_flush_lock);
+static LIST_HEAD(unmaps_to_do);
+
+static int timer_on;
+static long list_size;
+
+static void domain_remove_dev_info(struct dmar_domain *domain);
+
+#ifdef CONFIG_DMAR_DEFAULT_ON
+int dmar_disabled = 0;
+#else
+int dmar_disabled = 1;
+#endif /*CONFIG_DMAR_DEFAULT_ON*/
+
+static int dmar_map_gfx = 1;
+static int dmar_forcedac;
+static int intel_iommu_strict;
+static int intel_iommu_superpage = 1;
+
+#define DUMMY_DEVICE_DOMAIN_INFO ((struct device_domain_info *)(-1))
+static DEFINE_SPINLOCK(device_domain_lock);
+static LIST_HEAD(device_domain_list);
+
+static struct iommu_ops intel_iommu_ops;
+
+static int __init intel_iommu_setup(char *str)
+{
+	if (!str)
+		return -EINVAL;
+	while (*str) {
+		if (!strncmp(str, "on", 2)) {
+			dmar_disabled = 0;
+			printk(KERN_INFO "Intel-IOMMU: enabled\n");
+		} else if (!strncmp(str, "off", 3)) {
+			dmar_disabled = 1;
+			printk(KERN_INFO "Intel-IOMMU: disabled\n");
+		} else if (!strncmp(str, "igfx_off", 8)) {
+			dmar_map_gfx = 0;
+			printk(KERN_INFO
+				"Intel-IOMMU: disable GFX device mapping\n");
+		} else if (!strncmp(str, "forcedac", 8)) {
+			printk(KERN_INFO
+				"Intel-IOMMU: Forcing DAC for PCI devices\n");
+			dmar_forcedac = 1;
+		} else if (!strncmp(str, "strict", 6)) {
+			printk(KERN_INFO
+				"Intel-IOMMU: disable batched IOTLB flush\n");
+			intel_iommu_strict = 1;
+		} else if (!strncmp(str, "sp_off", 6)) {
+			printk(KERN_INFO
+				"Intel-IOMMU: disable supported super page\n");
+			intel_iommu_superpage = 0;
+		}
+
+		str += strcspn(str, ",");
+		while (*str == ',')
+			str++;
+	}
+	return 0;
+}
+__setup("intel_iommu=", intel_iommu_setup);
+
+static struct kmem_cache *iommu_domain_cache;
+static struct kmem_cache *iommu_devinfo_cache;
+static struct kmem_cache *iommu_iova_cache;
+
+static inline void *alloc_pgtable_page(int node)
+{
+	struct page *page;
+	void *vaddr = NULL;
+
+	page = alloc_pages_node(node, GFP_ATOMIC | __GFP_ZERO, 0);
+	if (page)
+		vaddr = page_address(page);
+	return vaddr;
+}
+
+static inline void free_pgtable_page(void *vaddr)
+{
+	free_page((unsigned long)vaddr);
+}
+
+static inline void *alloc_domain_mem(void)
+{
+	return kmem_cache_alloc(iommu_domain_cache, GFP_ATOMIC);
+}
+
+static void free_domain_mem(void *vaddr)
+{
+	kmem_cache_free(iommu_domain_cache, vaddr);
+}
+
+static inline void * alloc_devinfo_mem(void)
+{
+	return kmem_cache_alloc(iommu_devinfo_cache, GFP_ATOMIC);
+}
+
+static inline void free_devinfo_mem(void *vaddr)
+{
+	kmem_cache_free(iommu_devinfo_cache, vaddr);
+}
+
+struct iova *alloc_iova_mem(void)
+{
+	return kmem_cache_alloc(iommu_iova_cache, GFP_ATOMIC);
+}
+
+void free_iova_mem(struct iova *iova)
+{
+	kmem_cache_free(iommu_iova_cache, iova);
+}
+
+
+static int __iommu_calculate_agaw(struct intel_iommu *iommu, int max_gaw)
+{
+	unsigned long sagaw;
+	int agaw = -1;
+
+	sagaw = cap_sagaw(iommu->cap);
+	for (agaw = width_to_agaw(max_gaw);
+	     agaw >= 0; agaw--) {
+		if (test_bit(agaw, &sagaw))
+			break;
+	}
+
+	return agaw;
+}
+
+/*
+ * Calculate max SAGAW for each iommu.
+ */
+int iommu_calculate_max_sagaw(struct intel_iommu *iommu)
+{
+	return __iommu_calculate_agaw(iommu, MAX_AGAW_WIDTH);
+}
+
+/*
+ * calculate agaw for each iommu.
+ * "SAGAW" may be different across iommus, use a default agaw, and
+ * get a supported less agaw for iommus that don't support the default agaw.
+ */
+int iommu_calculate_agaw(struct intel_iommu *iommu)
+{
+	return __iommu_calculate_agaw(iommu, DEFAULT_DOMAIN_ADDRESS_WIDTH);
+}
+
+/* This functionin only returns single iommu in a domain */
+static struct intel_iommu *domain_get_iommu(struct dmar_domain *domain)
+{
+	int iommu_id;
+
+	/* si_domain and vm domain should not get here. */
+	BUG_ON(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE);
+	BUG_ON(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY);
+
+	iommu_id = find_first_bit(&domain->iommu_bmp, g_num_of_iommus);
+	if (iommu_id < 0 || iommu_id >= g_num_of_iommus)
+		return NULL;
+
+	return g_iommus[iommu_id];
+}
+
+static void domain_update_iommu_coherency(struct dmar_domain *domain)
+{
+	int i;
+
+	domain->iommu_coherency = 1;
+
+	for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
+		if (!ecap_coherent(g_iommus[i]->ecap)) {
+			domain->iommu_coherency = 0;
+			break;
+		}
+	}
+}
+
+static void domain_update_iommu_snooping(struct dmar_domain *domain)
+{
+	int i;
+
+	domain->iommu_snooping = 1;
+
+	for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
+		if (!ecap_sc_support(g_iommus[i]->ecap)) {
+			domain->iommu_snooping = 0;
+			break;
+		}
+	}
+}
+
+static void domain_update_iommu_superpage(struct dmar_domain *domain)
+{
+	int i, mask = 0xf;
+
+	if (!intel_iommu_superpage) {
+		domain->iommu_superpage = 0;
+		return;
+	}
+
+	domain->iommu_superpage = 4; /* 1TiB */
+
+	for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
+		mask |= cap_super_page_val(g_iommus[i]->cap);
+		if (!mask) {
+			break;
+		}
+	}
+	domain->iommu_superpage = fls(mask);
+}
+
+/* Some capabilities may be different across iommus */
+static void domain_update_iommu_cap(struct dmar_domain *domain)
+{
+	domain_update_iommu_coherency(domain);
+	domain_update_iommu_snooping(domain);
+	domain_update_iommu_superpage(domain);
+}
+
+static struct intel_iommu *device_to_iommu(int segment, u8 bus, u8 devfn)
+{
+	struct dmar_drhd_unit *drhd = NULL;
+	int i;
+
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+		if (segment != drhd->segment)
+			continue;
+
+		for (i = 0; i < drhd->devices_cnt; i++) {
+			if (drhd->devices[i] &&
+			    drhd->devices[i]->bus->number == bus &&
+			    drhd->devices[i]->devfn == devfn)
+				return drhd->iommu;
+			if (drhd->devices[i] &&
+			    drhd->devices[i]->subordinate &&
+			    drhd->devices[i]->subordinate->number <= bus &&
+			    drhd->devices[i]->subordinate->subordinate >= bus)
+				return drhd->iommu;
+		}
+
+		if (drhd->include_all)
+			return drhd->iommu;
+	}
+
+	return NULL;
+}
+
+static void domain_flush_cache(struct dmar_domain *domain,
+			       void *addr, int size)
+{
+	if (!domain->iommu_coherency)
+		clflush_cache_range(addr, size);
+}
+
+/* Gets context entry for a given bus and devfn */
+static struct context_entry * device_to_context_entry(struct intel_iommu *iommu,
+		u8 bus, u8 devfn)
+{
+	struct root_entry *root;
+	struct context_entry *context;
+	unsigned long phy_addr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	root = &iommu->root_entry[bus];
+	context = get_context_addr_from_root(root);
+	if (!context) {
+		context = (struct context_entry *)
+				alloc_pgtable_page(iommu->node);
+		if (!context) {
+			spin_unlock_irqrestore(&iommu->lock, flags);
+			return NULL;
+		}
+		__iommu_flush_cache(iommu, (void *)context, CONTEXT_SIZE);
+		phy_addr = virt_to_phys((void *)context);
+		set_root_value(root, phy_addr);
+		set_root_present(root);
+		__iommu_flush_cache(iommu, root, sizeof(*root));
+	}
+	spin_unlock_irqrestore(&iommu->lock, flags);
+	return &context[devfn];
+}
+
+static int device_context_mapped(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	struct root_entry *root;
+	struct context_entry *context;
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	root = &iommu->root_entry[bus];
+	context = get_context_addr_from_root(root);
+	if (!context) {
+		ret = 0;
+		goto out;
+	}
+	ret = context_present(&context[devfn]);
+out:
+	spin_unlock_irqrestore(&iommu->lock, flags);
+	return ret;
+}
+
+static void clear_context_table(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	struct root_entry *root;
+	struct context_entry *context;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	root = &iommu->root_entry[bus];
+	context = get_context_addr_from_root(root);
+	if (context) {
+		context_clear_entry(&context[devfn]);
+		__iommu_flush_cache(iommu, &context[devfn], \
+			sizeof(*context));
+	}
+	spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+static void free_context_table(struct intel_iommu *iommu)
+{
+	struct root_entry *root;
+	int i;
+	unsigned long flags;
+	struct context_entry *context;
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	if (!iommu->root_entry) {
+		goto out;
+	}
+	for (i = 0; i < ROOT_ENTRY_NR; i++) {
+		root = &iommu->root_entry[i];
+		context = get_context_addr_from_root(root);
+		if (context)
+			free_pgtable_page(context);
+	}
+	free_pgtable_page(iommu->root_entry);
+	iommu->root_entry = NULL;
+out:
+	spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
+				      unsigned long pfn, int large_level)
+{
+	int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+	struct dma_pte *parent, *pte = NULL;
+	int level = agaw_to_level(domain->agaw);
+	int offset, target_level;
+
+	BUG_ON(!domain->pgd);
+	BUG_ON(addr_width < BITS_PER_LONG && pfn >> addr_width);
+	parent = domain->pgd;
+
+	/* Search pte */
+	if (!large_level)
+		target_level = 1;
+	else
+		target_level = large_level;
+
+	while (level > 0) {
+		void *tmp_page;
+
+		offset = pfn_level_offset(pfn, level);
+		pte = &parent[offset];
+		if (!large_level && (pte->val & DMA_PTE_LARGE_PAGE))
+			break;
+		if (level == target_level)
+			break;
+
+		if (!dma_pte_present(pte)) {
+			uint64_t pteval;
+
+			tmp_page = alloc_pgtable_page(domain->nid);
+
+			if (!tmp_page)
+				return NULL;
+
+			domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE);
+			pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE;
+			if (cmpxchg64(&pte->val, 0ULL, pteval)) {
+				/* Someone else set it while we were thinking; use theirs. */
+				free_pgtable_page(tmp_page);
+			} else {
+				dma_pte_addr(pte);
+				domain_flush_cache(domain, pte, sizeof(*pte));
+			}
+		}
+		parent = phys_to_virt(dma_pte_addr(pte));
+		level--;
+	}
+
+	return pte;
+}
+
+
+/* return address's pte at specific level */
+static struct dma_pte *dma_pfn_level_pte(struct dmar_domain *domain,
+					 unsigned long pfn,
+					 int level, int *large_page)
+{
+	struct dma_pte *parent, *pte = NULL;
+	int total = agaw_to_level(domain->agaw);
+	int offset;
+
+	parent = domain->pgd;
+	while (level <= total) {
+		offset = pfn_level_offset(pfn, total);
+		pte = &parent[offset];
+		if (level == total)
+			return pte;
+
+		if (!dma_pte_present(pte)) {
+			*large_page = total;
+			break;
+		}
+
+		if (pte->val & DMA_PTE_LARGE_PAGE) {
+			*large_page = total;
+			return pte;
+		}
+
+		parent = phys_to_virt(dma_pte_addr(pte));
+		total--;
+	}
+	return NULL;
+}
+
+/* clear last level pte, a tlb flush should be followed */
+static void dma_pte_clear_range(struct dmar_domain *domain,
+				unsigned long start_pfn,
+				unsigned long last_pfn)
+{
+	int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+	unsigned int large_page = 1;
+	struct dma_pte *first_pte, *pte;
+
+	BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
+	BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
+	BUG_ON(start_pfn > last_pfn);
+
+	/* we don't need lock here; nobody else touches the iova range */
+	do {
+		large_page = 1;
+		first_pte = pte = dma_pfn_level_pte(domain, start_pfn, 1, &large_page);
+		if (!pte) {
+			start_pfn = align_to_level(start_pfn + 1, large_page + 1);
+			continue;
+		}
+		do {
+			dma_clear_pte(pte);
+			start_pfn += lvl_to_nr_pages(large_page);
+			pte++;
+		} while (start_pfn <= last_pfn && !first_pte_in_page(pte));
+
+		domain_flush_cache(domain, first_pte,
+				   (void *)pte - (void *)first_pte);
+
+	} while (start_pfn && start_pfn <= last_pfn);
+}
+
+/* free page table pages. last level pte should already be cleared */
+static void dma_pte_free_pagetable(struct dmar_domain *domain,
+				   unsigned long start_pfn,
+				   unsigned long last_pfn)
+{
+	int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+	struct dma_pte *first_pte, *pte;
+	int total = agaw_to_level(domain->agaw);
+	int level;
+	unsigned long tmp;
+	int large_page = 2;
+
+	BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
+	BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
+	BUG_ON(start_pfn > last_pfn);
+
+	/* We don't need lock here; nobody else touches the iova range */
+	level = 2;
+	while (level <= total) {
+		tmp = align_to_level(start_pfn, level);
+
+		/* If we can't even clear one PTE at this level, we're done */
+		if (tmp + level_size(level) - 1 > last_pfn)
+			return;
+
+		do {
+			large_page = level;
+			first_pte = pte = dma_pfn_level_pte(domain, tmp, level, &large_page);
+			if (large_page > level)
+				level = large_page + 1;
+			if (!pte) {
+				tmp = align_to_level(tmp + 1, level + 1);
+				continue;
+			}
+			do {
+				if (dma_pte_present(pte)) {
+					free_pgtable_page(phys_to_virt(dma_pte_addr(pte)));
+					dma_clear_pte(pte);
+				}
+				pte++;
+				tmp += level_size(level);
+			} while (!first_pte_in_page(pte) &&
+				 tmp + level_size(level) - 1 <= last_pfn);
+
+			domain_flush_cache(domain, first_pte,
+					   (void *)pte - (void *)first_pte);
+			
+		} while (tmp && tmp + level_size(level) - 1 <= last_pfn);
+		level++;
+	}
+	/* free pgd */
+	if (start_pfn == 0 && last_pfn == DOMAIN_MAX_PFN(domain->gaw)) {
+		free_pgtable_page(domain->pgd);
+		domain->pgd = NULL;
+	}
+}
+
+/* iommu handling */
+static int iommu_alloc_root_entry(struct intel_iommu *iommu)
+{
+	struct root_entry *root;
+	unsigned long flags;
+
+	root = (struct root_entry *)alloc_pgtable_page(iommu->node);
+	if (!root)
+		return -ENOMEM;
+
+	__iommu_flush_cache(iommu, root, ROOT_SIZE);
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	iommu->root_entry = root;
+	spin_unlock_irqrestore(&iommu->lock, flags);
+
+	return 0;
+}
+
+static void iommu_set_root_entry(struct intel_iommu *iommu)
+{
+	void *addr;
+	u32 sts;
+	unsigned long flag;
+
+	addr = iommu->root_entry;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	dmar_writeq(iommu->reg + DMAR_RTADDR_REG, virt_to_phys(addr));
+
+	writel(iommu->gcmd | DMA_GCMD_SRTP, iommu->reg + DMAR_GCMD_REG);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (sts & DMA_GSTS_RTPS), sts);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+static void iommu_flush_write_buffer(struct intel_iommu *iommu)
+{
+	u32 val;
+	unsigned long flag;
+
+	if (!rwbf_quirk && !cap_rwbf(iommu->cap))
+		return;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	writel(iommu->gcmd | DMA_GCMD_WBF, iommu->reg + DMAR_GCMD_REG);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (!(val & DMA_GSTS_WBFS)), val);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+/* return value determine if we need a write buffer flush */
+static void __iommu_flush_context(struct intel_iommu *iommu,
+				  u16 did, u16 source_id, u8 function_mask,
+				  u64 type)
+{
+	u64 val = 0;
+	unsigned long flag;
+
+	switch (type) {
+	case DMA_CCMD_GLOBAL_INVL:
+		val = DMA_CCMD_GLOBAL_INVL;
+		break;
+	case DMA_CCMD_DOMAIN_INVL:
+		val = DMA_CCMD_DOMAIN_INVL|DMA_CCMD_DID(did);
+		break;
+	case DMA_CCMD_DEVICE_INVL:
+		val = DMA_CCMD_DEVICE_INVL|DMA_CCMD_DID(did)
+			| DMA_CCMD_SID(source_id) | DMA_CCMD_FM(function_mask);
+		break;
+	default:
+		BUG();
+	}
+	val |= DMA_CCMD_ICC;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	dmar_writeq(iommu->reg + DMAR_CCMD_REG, val);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_CCMD_REG,
+		dmar_readq, (!(val & DMA_CCMD_ICC)), val);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+}
+
+/* return value determine if we need a write buffer flush */
+static void __iommu_flush_iotlb(struct intel_iommu *iommu, u16 did,
+				u64 addr, unsigned int size_order, u64 type)
+{
+	int tlb_offset = ecap_iotlb_offset(iommu->ecap);
+	u64 val = 0, val_iva = 0;
+	unsigned long flag;
+
+	switch (type) {
+	case DMA_TLB_GLOBAL_FLUSH:
+		/* global flush doesn't need set IVA_REG */
+		val = DMA_TLB_GLOBAL_FLUSH|DMA_TLB_IVT;
+		break;
+	case DMA_TLB_DSI_FLUSH:
+		val = DMA_TLB_DSI_FLUSH|DMA_TLB_IVT|DMA_TLB_DID(did);
+		break;
+	case DMA_TLB_PSI_FLUSH:
+		val = DMA_TLB_PSI_FLUSH|DMA_TLB_IVT|DMA_TLB_DID(did);
+		/* Note: always flush non-leaf currently */
+		val_iva = size_order | addr;
+		break;
+	default:
+		BUG();
+	}
+	/* Note: set drain read/write */
+#if 0
+	/*
+	 * This is probably to be super secure.. Looks like we can
+	 * ignore it without any impact.
+	 */
+	if (cap_read_drain(iommu->cap))
+		val |= DMA_TLB_READ_DRAIN;
+#endif
+	if (cap_write_drain(iommu->cap))
+		val |= DMA_TLB_WRITE_DRAIN;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	/* Note: Only uses first TLB reg currently */
+	if (val_iva)
+		dmar_writeq(iommu->reg + tlb_offset, val_iva);
+	dmar_writeq(iommu->reg + tlb_offset + 8, val);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, tlb_offset + 8,
+		dmar_readq, (!(val & DMA_TLB_IVT)), val);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+
+	/* check IOTLB invalidation granularity */
+	if (DMA_TLB_IAIG(val) == 0)
+		printk(KERN_ERR"IOMMU: flush IOTLB failed\n");
+	if (DMA_TLB_IAIG(val) != DMA_TLB_IIRG(type))
+		pr_debug("IOMMU: tlb flush request %Lx, actual %Lx\n",
+			(unsigned long long)DMA_TLB_IIRG(type),
+			(unsigned long long)DMA_TLB_IAIG(val));
+}
+
+static struct device_domain_info *iommu_support_dev_iotlb(
+	struct dmar_domain *domain, int segment, u8 bus, u8 devfn)
+{
+	int found = 0;
+	unsigned long flags;
+	struct device_domain_info *info;
+	struct intel_iommu *iommu = device_to_iommu(segment, bus, devfn);
+
+	if (!ecap_dev_iotlb_support(iommu->ecap))
+		return NULL;
+
+	if (!iommu->qi)
+		return NULL;
+
+	spin_lock_irqsave(&device_domain_lock, flags);
+	list_for_each_entry(info, &domain->devices, link)
+		if (info->bus == bus && info->devfn == devfn) {
+			found = 1;
+			break;
+		}
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+
+	if (!found || !info->dev)
+		return NULL;
+
+	if (!pci_find_ext_capability(info->dev, PCI_EXT_CAP_ID_ATS))
+		return NULL;
+
+	if (!dmar_find_matched_atsr_unit(info->dev))
+		return NULL;
+
+	info->iommu = iommu;
+
+	return info;
+}
+
+static void iommu_enable_dev_iotlb(struct device_domain_info *info)
+{
+	if (!info)
+		return;
+
+	pci_enable_ats(info->dev, VTD_PAGE_SHIFT);
+}
+
+static void iommu_disable_dev_iotlb(struct device_domain_info *info)
+{
+	if (!info->dev || !pci_ats_enabled(info->dev))
+		return;
+
+	pci_disable_ats(info->dev);
+}
+
+static void iommu_flush_dev_iotlb(struct dmar_domain *domain,
+				  u64 addr, unsigned mask)
+{
+	u16 sid, qdep;
+	unsigned long flags;
+	struct device_domain_info *info;
+
+	spin_lock_irqsave(&device_domain_lock, flags);
+	list_for_each_entry(info, &domain->devices, link) {
+		if (!info->dev || !pci_ats_enabled(info->dev))
+			continue;
+
+		sid = info->bus << 8 | info->devfn;
+		qdep = pci_ats_queue_depth(info->dev);
+		qi_flush_dev_iotlb(info->iommu, sid, qdep, addr, mask);
+	}
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+}
+
+static void iommu_flush_iotlb_psi(struct intel_iommu *iommu, u16 did,
+				  unsigned long pfn, unsigned int pages, int map)
+{
+	unsigned int mask = ilog2(__roundup_pow_of_two(pages));
+	uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
+
+	BUG_ON(pages == 0);
+
+	/*
+	 * Fallback to domain selective flush if no PSI support or the size is
+	 * too big.
+	 * PSI requires page size to be 2 ^ x, and the base address is naturally
+	 * aligned to the size
+	 */
+	if (!cap_pgsel_inv(iommu->cap) || mask > cap_max_amask_val(iommu->cap))
+		iommu->flush.flush_iotlb(iommu, did, 0, 0,
+						DMA_TLB_DSI_FLUSH);
+	else
+		iommu->flush.flush_iotlb(iommu, did, addr, mask,
+						DMA_TLB_PSI_FLUSH);
+
+	/*
+	 * In caching mode, changes of pages from non-present to present require
+	 * flush. However, device IOTLB doesn't need to be flushed in this case.
+	 */
+	if (!cap_caching_mode(iommu->cap) || !map)
+		iommu_flush_dev_iotlb(iommu->domains[did], addr, mask);
+}
+
+static void iommu_disable_protect_mem_regions(struct intel_iommu *iommu)
+{
+	u32 pmen;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+	pmen = readl(iommu->reg + DMAR_PMEN_REG);
+	pmen &= ~DMA_PMEN_EPM;
+	writel(pmen, iommu->reg + DMAR_PMEN_REG);
+
+	/* wait for the protected region status bit to clear */
+	IOMMU_WAIT_OP(iommu, DMAR_PMEN_REG,
+		readl, !(pmen & DMA_PMEN_PRS), pmen);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+static int iommu_enable_translation(struct intel_iommu *iommu)
+{
+	u32 sts;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+	iommu->gcmd |= DMA_GCMD_TE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (sts & DMA_GSTS_TES), sts);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+	return 0;
+}
+
+static int iommu_disable_translation(struct intel_iommu *iommu)
+{
+	u32 sts;
+	unsigned long flag;
+
+	spin_lock_irqsave(&iommu->register_lock, flag);
+	iommu->gcmd &= ~DMA_GCMD_TE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	/* Make sure hardware complete it */
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (!(sts & DMA_GSTS_TES)), sts);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flag);
+	return 0;
+}
+
+
+static int iommu_init_domains(struct intel_iommu *iommu)
+{
+	unsigned long ndomains;
+	unsigned long nlongs;
+
+	ndomains = cap_ndoms(iommu->cap);
+	pr_debug("IOMMU %d: Number of Domains supportd <%ld>\n", iommu->seq_id,
+			ndomains);
+	nlongs = BITS_TO_LONGS(ndomains);
+
+	spin_lock_init(&iommu->lock);
+
+	/* TBD: there might be 64K domains,
+	 * consider other allocation for future chip
+	 */
+	iommu->domain_ids = kcalloc(nlongs, sizeof(unsigned long), GFP_KERNEL);
+	if (!iommu->domain_ids) {
+		printk(KERN_ERR "Allocating domain id array failed\n");
+		return -ENOMEM;
+	}
+	iommu->domains = kcalloc(ndomains, sizeof(struct dmar_domain *),
+			GFP_KERNEL);
+	if (!iommu->domains) {
+		printk(KERN_ERR "Allocating domain array failed\n");
+		return -ENOMEM;
+	}
+
+	/*
+	 * if Caching mode is set, then invalid translations are tagged
+	 * with domainid 0. Hence we need to pre-allocate it.
+	 */
+	if (cap_caching_mode(iommu->cap))
+		set_bit(0, iommu->domain_ids);
+	return 0;
+}
+
+
+static void domain_exit(struct dmar_domain *domain);
+static void vm_domain_exit(struct dmar_domain *domain);
+
+void free_dmar_iommu(struct intel_iommu *iommu)
+{
+	struct dmar_domain *domain;
+	int i;
+	unsigned long flags;
+
+	if ((iommu->domains) && (iommu->domain_ids)) {
+		for_each_set_bit(i, iommu->domain_ids, cap_ndoms(iommu->cap)) {
+			domain = iommu->domains[i];
+			clear_bit(i, iommu->domain_ids);
+
+			spin_lock_irqsave(&domain->iommu_lock, flags);
+			if (--domain->iommu_count == 0) {
+				if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE)
+					vm_domain_exit(domain);
+				else
+					domain_exit(domain);
+			}
+			spin_unlock_irqrestore(&domain->iommu_lock, flags);
+		}
+	}
+
+	if (iommu->gcmd & DMA_GCMD_TE)
+		iommu_disable_translation(iommu);
+
+	if (iommu->irq) {
+		irq_set_handler_data(iommu->irq, NULL);
+		/* This will mask the irq */
+		free_irq(iommu->irq, iommu);
+		destroy_irq(iommu->irq);
+	}
+
+	kfree(iommu->domains);
+	kfree(iommu->domain_ids);
+
+	g_iommus[iommu->seq_id] = NULL;
+
+	/* if all iommus are freed, free g_iommus */
+	for (i = 0; i < g_num_of_iommus; i++) {
+		if (g_iommus[i])
+			break;
+	}
+
+	if (i == g_num_of_iommus)
+		kfree(g_iommus);
+
+	/* free context mapping */
+	free_context_table(iommu);
+}
+
+static struct dmar_domain *alloc_domain(void)
+{
+	struct dmar_domain *domain;
+
+	domain = alloc_domain_mem();
+	if (!domain)
+		return NULL;
+
+	domain->nid = -1;
+	memset(&domain->iommu_bmp, 0, sizeof(unsigned long));
+	domain->flags = 0;
+
+	return domain;
+}
+
+static int iommu_attach_domain(struct dmar_domain *domain,
+			       struct intel_iommu *iommu)
+{
+	int num;
+	unsigned long ndomains;
+	unsigned long flags;
+
+	ndomains = cap_ndoms(iommu->cap);
+
+	spin_lock_irqsave(&iommu->lock, flags);
+
+	num = find_first_zero_bit(iommu->domain_ids, ndomains);
+	if (num >= ndomains) {
+		spin_unlock_irqrestore(&iommu->lock, flags);
+		printk(KERN_ERR "IOMMU: no free domain ids\n");
+		return -ENOMEM;
+	}
+
+	domain->id = num;
+	set_bit(num, iommu->domain_ids);
+	set_bit(iommu->seq_id, &domain->iommu_bmp);
+	iommu->domains[num] = domain;
+	spin_unlock_irqrestore(&iommu->lock, flags);
+
+	return 0;
+}
+
+static void iommu_detach_domain(struct dmar_domain *domain,
+				struct intel_iommu *iommu)
+{
+	unsigned long flags;
+	int num, ndomains;
+	int found = 0;
+
+	spin_lock_irqsave(&iommu->lock, flags);
+	ndomains = cap_ndoms(iommu->cap);
+	for_each_set_bit(num, iommu->domain_ids, ndomains) {
+		if (iommu->domains[num] == domain) {
+			found = 1;
+			break;
+		}
+	}
+
+	if (found) {
+		clear_bit(num, iommu->domain_ids);
+		clear_bit(iommu->seq_id, &domain->iommu_bmp);
+		iommu->domains[num] = NULL;
+	}
+	spin_unlock_irqrestore(&iommu->lock, flags);
+}
+
+static struct iova_domain reserved_iova_list;
+static struct lock_class_key reserved_rbtree_key;
+
+static int dmar_init_reserved_ranges(void)
+{
+	struct pci_dev *pdev = NULL;
+	struct iova *iova;
+	int i;
+
+	init_iova_domain(&reserved_iova_list, DMA_32BIT_PFN);
+
+	lockdep_set_class(&reserved_iova_list.iova_rbtree_lock,
+		&reserved_rbtree_key);
+
+	/* IOAPIC ranges shouldn't be accessed by DMA */
+	iova = reserve_iova(&reserved_iova_list, IOVA_PFN(IOAPIC_RANGE_START),
+		IOVA_PFN(IOAPIC_RANGE_END));
+	if (!iova) {
+		printk(KERN_ERR "Reserve IOAPIC range failed\n");
+		return -ENODEV;
+	}
+
+	/* Reserve all PCI MMIO to avoid peer-to-peer access */
+	for_each_pci_dev(pdev) {
+		struct resource *r;
+
+		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+			r = &pdev->resource[i];
+			if (!r->flags || !(r->flags & IORESOURCE_MEM))
+				continue;
+			iova = reserve_iova(&reserved_iova_list,
+					    IOVA_PFN(r->start),
+					    IOVA_PFN(r->end));
+			if (!iova) {
+				printk(KERN_ERR "Reserve iova failed\n");
+				return -ENODEV;
+			}
+		}
+	}
+	return 0;
+}
+
+static void domain_reserve_special_ranges(struct dmar_domain *domain)
+{
+	copy_reserved_iova(&reserved_iova_list, &domain->iovad);
+}
+
+static inline int guestwidth_to_adjustwidth(int gaw)
+{
+	int agaw;
+	int r = (gaw - 12) % 9;
+
+	if (r == 0)
+		agaw = gaw;
+	else
+		agaw = gaw + 9 - r;
+	if (agaw > 64)
+		agaw = 64;
+	return agaw;
+}
+
+static int domain_init(struct dmar_domain *domain, int guest_width)
+{
+	struct intel_iommu *iommu;
+	int adjust_width, agaw;
+	unsigned long sagaw;
+
+	init_iova_domain(&domain->iovad, DMA_32BIT_PFN);
+	spin_lock_init(&domain->iommu_lock);
+
+	domain_reserve_special_ranges(domain);
+
+	/* calculate AGAW */
+	iommu = domain_get_iommu(domain);
+	if (guest_width > cap_mgaw(iommu->cap))
+		guest_width = cap_mgaw(iommu->cap);
+	domain->gaw = guest_width;
+	adjust_width = guestwidth_to_adjustwidth(guest_width);
+	agaw = width_to_agaw(adjust_width);
+	sagaw = cap_sagaw(iommu->cap);
+	if (!test_bit(agaw, &sagaw)) {
+		/* hardware doesn't support it, choose a bigger one */
+		pr_debug("IOMMU: hardware doesn't support agaw %d\n", agaw);
+		agaw = find_next_bit(&sagaw, 5, agaw);
+		if (agaw >= 5)
+			return -ENODEV;
+	}
+	domain->agaw = agaw;
+	INIT_LIST_HEAD(&domain->devices);
+
+	if (ecap_coherent(iommu->ecap))
+		domain->iommu_coherency = 1;
+	else
+		domain->iommu_coherency = 0;
+
+	if (ecap_sc_support(iommu->ecap))
+		domain->iommu_snooping = 1;
+	else
+		domain->iommu_snooping = 0;
+
+	domain->iommu_superpage = fls(cap_super_page_val(iommu->cap));
+	domain->iommu_count = 1;
+	domain->nid = iommu->node;
+
+	/* always allocate the top pgd */
+	domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid);
+	if (!domain->pgd)
+		return -ENOMEM;
+	__iommu_flush_cache(iommu, domain->pgd, PAGE_SIZE);
+	return 0;
+}
+
+static void domain_exit(struct dmar_domain *domain)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu;
+
+	/* Domain 0 is reserved, so dont process it */
+	if (!domain)
+		return;
+
+	/* Flush any lazy unmaps that may reference this domain */
+	if (!intel_iommu_strict)
+		flush_unmaps_timeout(0);
+
+	domain_remove_dev_info(domain);
+	/* destroy iovas */
+	put_iova_domain(&domain->iovad);
+
+	/* clear ptes */
+	dma_pte_clear_range(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+
+	/* free page tables */
+	dma_pte_free_pagetable(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+
+	for_each_active_iommu(iommu, drhd)
+		if (test_bit(iommu->seq_id, &domain->iommu_bmp))
+			iommu_detach_domain(domain, iommu);
+
+	free_domain_mem(domain);
+}
+
+static int domain_context_mapping_one(struct dmar_domain *domain, int segment,
+				 u8 bus, u8 devfn, int translation)
+{
+	struct context_entry *context;
+	unsigned long flags;
+	struct intel_iommu *iommu;
+	struct dma_pte *pgd;
+	unsigned long num;
+	unsigned long ndomains;
+	int id;
+	int agaw;
+	struct device_domain_info *info = NULL;
+
+	pr_debug("Set context mapping for %02x:%02x.%d\n",
+		bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
+
+	BUG_ON(!domain->pgd);
+	BUG_ON(translation != CONTEXT_TT_PASS_THROUGH &&
+	       translation != CONTEXT_TT_MULTI_LEVEL);
+
+	iommu = device_to_iommu(segment, bus, devfn);
+	if (!iommu)
+		return -ENODEV;
+
+	context = device_to_context_entry(iommu, bus, devfn);
+	if (!context)
+		return -ENOMEM;
+	spin_lock_irqsave(&iommu->lock, flags);
+	if (context_present(context)) {
+		spin_unlock_irqrestore(&iommu->lock, flags);
+		return 0;
+	}
+
+	id = domain->id;
+	pgd = domain->pgd;
+
+	if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
+	    domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) {
+		int found = 0;
+
+		/* find an available domain id for this device in iommu */
+		ndomains = cap_ndoms(iommu->cap);
+		for_each_set_bit(num, iommu->domain_ids, ndomains) {
+			if (iommu->domains[num] == domain) {
+				id = num;
+				found = 1;
+				break;
+			}
+		}
+
+		if (found == 0) {
+			num = find_first_zero_bit(iommu->domain_ids, ndomains);
+			if (num >= ndomains) {
+				spin_unlock_irqrestore(&iommu->lock, flags);
+				printk(KERN_ERR "IOMMU: no free domain ids\n");
+				return -EFAULT;
+			}
+
+			set_bit(num, iommu->domain_ids);
+			iommu->domains[num] = domain;
+			id = num;
+		}
+
+		/* Skip top levels of page tables for
+		 * iommu which has less agaw than default.
+		 * Unnecessary for PT mode.
+		 */
+		if (translation != CONTEXT_TT_PASS_THROUGH) {
+			for (agaw = domain->agaw; agaw != iommu->agaw; agaw--) {
+				pgd = phys_to_virt(dma_pte_addr(pgd));
+				if (!dma_pte_present(pgd)) {
+					spin_unlock_irqrestore(&iommu->lock, flags);
+					return -ENOMEM;
+				}
+			}
+		}
+	}
+
+	context_set_domain_id(context, id);
+
+	if (translation != CONTEXT_TT_PASS_THROUGH) {
+		info = iommu_support_dev_iotlb(domain, segment, bus, devfn);
+		translation = info ? CONTEXT_TT_DEV_IOTLB :
+				     CONTEXT_TT_MULTI_LEVEL;
+	}
+	/*
+	 * In pass through mode, AW must be programmed to indicate the largest
+	 * AGAW value supported by hardware. And ASR is ignored by hardware.
+	 */
+	if (unlikely(translation == CONTEXT_TT_PASS_THROUGH))
+		context_set_address_width(context, iommu->msagaw);
+	else {
+		context_set_address_root(context, virt_to_phys(pgd));
+		context_set_address_width(context, iommu->agaw);
+	}
+
+	context_set_translation_type(context, translation);
+	context_set_fault_enable(context);
+	context_set_present(context);
+	domain_flush_cache(domain, context, sizeof(*context));
+
+	/*
+	 * It's a non-present to present mapping. If hardware doesn't cache
+	 * non-present entry we only need to flush the write-buffer. If the
+	 * _does_ cache non-present entries, then it does so in the special
+	 * domain #0, which we have to flush:
+	 */
+	if (cap_caching_mode(iommu->cap)) {
+		iommu->flush.flush_context(iommu, 0,
+					   (((u16)bus) << 8) | devfn,
+					   DMA_CCMD_MASK_NOBIT,
+					   DMA_CCMD_DEVICE_INVL);
+		iommu->flush.flush_iotlb(iommu, domain->id, 0, 0, DMA_TLB_DSI_FLUSH);
+	} else {
+		iommu_flush_write_buffer(iommu);
+	}
+	iommu_enable_dev_iotlb(info);
+	spin_unlock_irqrestore(&iommu->lock, flags);
+
+	spin_lock_irqsave(&domain->iommu_lock, flags);
+	if (!test_and_set_bit(iommu->seq_id, &domain->iommu_bmp)) {
+		domain->iommu_count++;
+		if (domain->iommu_count == 1)
+			domain->nid = iommu->node;
+		domain_update_iommu_cap(domain);
+	}
+	spin_unlock_irqrestore(&domain->iommu_lock, flags);
+	return 0;
+}
+
+static int
+domain_context_mapping(struct dmar_domain *domain, struct pci_dev *pdev,
+			int translation)
+{
+	int ret;
+	struct pci_dev *tmp, *parent;
+
+	ret = domain_context_mapping_one(domain, pci_domain_nr(pdev->bus),
+					 pdev->bus->number, pdev->devfn,
+					 translation);
+	if (ret)
+		return ret;
+
+	/* dependent device mapping */
+	tmp = pci_find_upstream_pcie_bridge(pdev);
+	if (!tmp)
+		return 0;
+	/* Secondary interface's bus number and devfn 0 */
+	parent = pdev->bus->self;
+	while (parent != tmp) {
+		ret = domain_context_mapping_one(domain,
+						 pci_domain_nr(parent->bus),
+						 parent->bus->number,
+						 parent->devfn, translation);
+		if (ret)
+			return ret;
+		parent = parent->bus->self;
+	}
+	if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */
+		return domain_context_mapping_one(domain,
+					pci_domain_nr(tmp->subordinate),
+					tmp->subordinate->number, 0,
+					translation);
+	else /* this is a legacy PCI bridge */
+		return domain_context_mapping_one(domain,
+						  pci_domain_nr(tmp->bus),
+						  tmp->bus->number,
+						  tmp->devfn,
+						  translation);
+}
+
+static int domain_context_mapped(struct pci_dev *pdev)
+{
+	int ret;
+	struct pci_dev *tmp, *parent;
+	struct intel_iommu *iommu;
+
+	iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+				pdev->devfn);
+	if (!iommu)
+		return -ENODEV;
+
+	ret = device_context_mapped(iommu, pdev->bus->number, pdev->devfn);
+	if (!ret)
+		return ret;
+	/* dependent device mapping */
+	tmp = pci_find_upstream_pcie_bridge(pdev);
+	if (!tmp)
+		return ret;
+	/* Secondary interface's bus number and devfn 0 */
+	parent = pdev->bus->self;
+	while (parent != tmp) {
+		ret = device_context_mapped(iommu, parent->bus->number,
+					    parent->devfn);
+		if (!ret)
+			return ret;
+		parent = parent->bus->self;
+	}
+	if (pci_is_pcie(tmp))
+		return device_context_mapped(iommu, tmp->subordinate->number,
+					     0);
+	else
+		return device_context_mapped(iommu, tmp->bus->number,
+					     tmp->devfn);
+}
+
+/* Returns a number of VTD pages, but aligned to MM page size */
+static inline unsigned long aligned_nrpages(unsigned long host_addr,
+					    size_t size)
+{
+	host_addr &= ~PAGE_MASK;
+	return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT;
+}
+
+/* Return largest possible superpage level for a given mapping */
+static inline int hardware_largepage_caps(struct dmar_domain *domain,
+					  unsigned long iov_pfn,
+					  unsigned long phy_pfn,
+					  unsigned long pages)
+{
+	int support, level = 1;
+	unsigned long pfnmerge;
+
+	support = domain->iommu_superpage;
+
+	/* To use a large page, the virtual *and* physical addresses
+	   must be aligned to 2MiB/1GiB/etc. Lower bits set in either
+	   of them will mean we have to use smaller pages. So just
+	   merge them and check both at once. */
+	pfnmerge = iov_pfn | phy_pfn;
+
+	while (support && !(pfnmerge & ~VTD_STRIDE_MASK)) {
+		pages >>= VTD_STRIDE_SHIFT;
+		if (!pages)
+			break;
+		pfnmerge >>= VTD_STRIDE_SHIFT;
+		level++;
+		support--;
+	}
+	return level;
+}
+
+static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+			    struct scatterlist *sg, unsigned long phys_pfn,
+			    unsigned long nr_pages, int prot)
+{
+	struct dma_pte *first_pte = NULL, *pte = NULL;
+	phys_addr_t uninitialized_var(pteval);
+	int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+	unsigned long sg_res;
+	unsigned int largepage_lvl = 0;
+	unsigned long lvl_pages = 0;
+
+	BUG_ON(addr_width < BITS_PER_LONG && (iov_pfn + nr_pages - 1) >> addr_width);
+
+	if ((prot & (DMA_PTE_READ|DMA_PTE_WRITE)) == 0)
+		return -EINVAL;
+
+	prot &= DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP;
+
+	if (sg)
+		sg_res = 0;
+	else {
+		sg_res = nr_pages + 1;
+		pteval = ((phys_addr_t)phys_pfn << VTD_PAGE_SHIFT) | prot;
+	}
+
+	while (nr_pages > 0) {
+		uint64_t tmp;
+
+		if (!sg_res) {
+			sg_res = aligned_nrpages(sg->offset, sg->length);
+			sg->dma_address = ((dma_addr_t)iov_pfn << VTD_PAGE_SHIFT) + sg->offset;
+			sg->dma_length = sg->length;
+			pteval = page_to_phys(sg_page(sg)) | prot;
+			phys_pfn = pteval >> VTD_PAGE_SHIFT;
+		}
+
+		if (!pte) {
+			largepage_lvl = hardware_largepage_caps(domain, iov_pfn, phys_pfn, sg_res);
+
+			first_pte = pte = pfn_to_dma_pte(domain, iov_pfn, largepage_lvl);
+			if (!pte)
+				return -ENOMEM;
+			/* It is large page*/
+			if (largepage_lvl > 1)
+				pteval |= DMA_PTE_LARGE_PAGE;
+			else
+				pteval &= ~(uint64_t)DMA_PTE_LARGE_PAGE;
+
+		}
+		/* We don't need lock here, nobody else
+		 * touches the iova range
+		 */
+		tmp = cmpxchg64_local(&pte->val, 0ULL, pteval);
+		if (tmp) {
+			static int dumps = 5;
+			printk(KERN_CRIT "ERROR: DMA PTE for vPFN 0x%lx already set (to %llx not %llx)\n",
+			       iov_pfn, tmp, (unsigned long long)pteval);
+			if (dumps) {
+				dumps--;
+				debug_dma_dump_mappings(NULL);
+			}
+			WARN_ON(1);
+		}
+
+		lvl_pages = lvl_to_nr_pages(largepage_lvl);
+
+		BUG_ON(nr_pages < lvl_pages);
+		BUG_ON(sg_res < lvl_pages);
+
+		nr_pages -= lvl_pages;
+		iov_pfn += lvl_pages;
+		phys_pfn += lvl_pages;
+		pteval += lvl_pages * VTD_PAGE_SIZE;
+		sg_res -= lvl_pages;
+
+		/* If the next PTE would be the first in a new page, then we
+		   need to flush the cache on the entries we've just written.
+		   And then we'll need to recalculate 'pte', so clear it and
+		   let it get set again in the if (!pte) block above.
+
+		   If we're done (!nr_pages) we need to flush the cache too.
+
+		   Also if we've been setting superpages, we may need to
+		   recalculate 'pte' and switch back to smaller pages for the
+		   end of the mapping, if the trailing size is not enough to
+		   use another superpage (i.e. sg_res < lvl_pages). */
+		pte++;
+		if (!nr_pages || first_pte_in_page(pte) ||
+		    (largepage_lvl > 1 && sg_res < lvl_pages)) {
+			domain_flush_cache(domain, first_pte,
+					   (void *)pte - (void *)first_pte);
+			pte = NULL;
+		}
+
+		if (!sg_res && nr_pages)
+			sg = sg_next(sg);
+	}
+	return 0;
+}
+
+static inline int domain_sg_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+				    struct scatterlist *sg, unsigned long nr_pages,
+				    int prot)
+{
+	return __domain_mapping(domain, iov_pfn, sg, 0, nr_pages, prot);
+}
+
+static inline int domain_pfn_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
+				     unsigned long phys_pfn, unsigned long nr_pages,
+				     int prot)
+{
+	return __domain_mapping(domain, iov_pfn, NULL, phys_pfn, nr_pages, prot);
+}
+
+static void iommu_detach_dev(struct intel_iommu *iommu, u8 bus, u8 devfn)
+{
+	if (!iommu)
+		return;
+
+	clear_context_table(iommu, bus, devfn);
+	iommu->flush.flush_context(iommu, 0, 0, 0,
+					   DMA_CCMD_GLOBAL_INVL);
+	iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
+}
+
+static void domain_remove_dev_info(struct dmar_domain *domain)
+{
+	struct device_domain_info *info;
+	unsigned long flags;
+	struct intel_iommu *iommu;
+
+	spin_lock_irqsave(&device_domain_lock, flags);
+	while (!list_empty(&domain->devices)) {
+		info = list_entry(domain->devices.next,
+			struct device_domain_info, link);
+		list_del(&info->link);
+		list_del(&info->global);
+		if (info->dev)
+			info->dev->dev.archdata.iommu = NULL;
+		spin_unlock_irqrestore(&device_domain_lock, flags);
+
+		iommu_disable_dev_iotlb(info);
+		iommu = device_to_iommu(info->segment, info->bus, info->devfn);
+		iommu_detach_dev(iommu, info->bus, info->devfn);
+		free_devinfo_mem(info);
+
+		spin_lock_irqsave(&device_domain_lock, flags);
+	}
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+}
+
+/*
+ * find_domain
+ * Note: we use struct pci_dev->dev.archdata.iommu stores the info
+ */
+static struct dmar_domain *
+find_domain(struct pci_dev *pdev)
+{
+	struct device_domain_info *info;
+
+	/* No lock here, assumes no domain exit in normal case */
+	info = pdev->dev.archdata.iommu;
+	if (info)
+		return info->domain;
+	return NULL;
+}
+
+/* domain is initialized */
+static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw)
+{
+	struct dmar_domain *domain, *found = NULL;
+	struct intel_iommu *iommu;
+	struct dmar_drhd_unit *drhd;
+	struct device_domain_info *info, *tmp;
+	struct pci_dev *dev_tmp;
+	unsigned long flags;
+	int bus = 0, devfn = 0;
+	int segment;
+	int ret;
+
+	domain = find_domain(pdev);
+	if (domain)
+		return domain;
+
+	segment = pci_domain_nr(pdev->bus);
+
+	dev_tmp = pci_find_upstream_pcie_bridge(pdev);
+	if (dev_tmp) {
+		if (pci_is_pcie(dev_tmp)) {
+			bus = dev_tmp->subordinate->number;
+			devfn = 0;
+		} else {
+			bus = dev_tmp->bus->number;
+			devfn = dev_tmp->devfn;
+		}
+		spin_lock_irqsave(&device_domain_lock, flags);
+		list_for_each_entry(info, &device_domain_list, global) {
+			if (info->segment == segment &&
+			    info->bus == bus && info->devfn == devfn) {
+				found = info->domain;
+				break;
+			}
+		}
+		spin_unlock_irqrestore(&device_domain_lock, flags);
+		/* pcie-pci bridge already has a domain, uses it */
+		if (found) {
+			domain = found;
+			goto found_domain;
+		}
+	}
+
+	domain = alloc_domain();
+	if (!domain)
+		goto error;
+
+	/* Allocate new domain for the device */
+	drhd = dmar_find_matched_drhd_unit(pdev);
+	if (!drhd) {
+		printk(KERN_ERR "IOMMU: can't find DMAR for device %s\n",
+			pci_name(pdev));
+		return NULL;
+	}
+	iommu = drhd->iommu;
+
+	ret = iommu_attach_domain(domain, iommu);
+	if (ret) {
+		free_domain_mem(domain);
+		goto error;
+	}
+
+	if (domain_init(domain, gaw)) {
+		domain_exit(domain);
+		goto error;
+	}
+
+	/* register pcie-to-pci device */
+	if (dev_tmp) {
+		info = alloc_devinfo_mem();
+		if (!info) {
+			domain_exit(domain);
+			goto error;
+		}
+		info->segment = segment;
+		info->bus = bus;
+		info->devfn = devfn;
+		info->dev = NULL;
+		info->domain = domain;
+		/* This domain is shared by devices under p2p bridge */
+		domain->flags |= DOMAIN_FLAG_P2P_MULTIPLE_DEVICES;
+
+		/* pcie-to-pci bridge already has a domain, uses it */
+		found = NULL;
+		spin_lock_irqsave(&device_domain_lock, flags);
+		list_for_each_entry(tmp, &device_domain_list, global) {
+			if (tmp->segment == segment &&
+			    tmp->bus == bus && tmp->devfn == devfn) {
+				found = tmp->domain;
+				break;
+			}
+		}
+		if (found) {
+			spin_unlock_irqrestore(&device_domain_lock, flags);
+			free_devinfo_mem(info);
+			domain_exit(domain);
+			domain = found;
+		} else {
+			list_add(&info->link, &domain->devices);
+			list_add(&info->global, &device_domain_list);
+			spin_unlock_irqrestore(&device_domain_lock, flags);
+		}
+	}
+
+found_domain:
+	info = alloc_devinfo_mem();
+	if (!info)
+		goto error;
+	info->segment = segment;
+	info->bus = pdev->bus->number;
+	info->devfn = pdev->devfn;
+	info->dev = pdev;
+	info->domain = domain;
+	spin_lock_irqsave(&device_domain_lock, flags);
+	/* somebody is fast */
+	found = find_domain(pdev);
+	if (found != NULL) {
+		spin_unlock_irqrestore(&device_domain_lock, flags);
+		if (found != domain) {
+			domain_exit(domain);
+			domain = found;
+		}
+		free_devinfo_mem(info);
+		return domain;
+	}
+	list_add(&info->link, &domain->devices);
+	list_add(&info->global, &device_domain_list);
+	pdev->dev.archdata.iommu = info;
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+	return domain;
+error:
+	/* recheck it here, maybe others set it */
+	return find_domain(pdev);
+}
+
+static int iommu_identity_mapping;
+#define IDENTMAP_ALL		1
+#define IDENTMAP_GFX		2
+#define IDENTMAP_AZALIA		4
+
+static int iommu_domain_identity_map(struct dmar_domain *domain,
+				     unsigned long long start,
+				     unsigned long long end)
+{
+	unsigned long first_vpfn = start >> VTD_PAGE_SHIFT;
+	unsigned long last_vpfn = end >> VTD_PAGE_SHIFT;
+
+	if (!reserve_iova(&domain->iovad, dma_to_mm_pfn(first_vpfn),
+			  dma_to_mm_pfn(last_vpfn))) {
+		printk(KERN_ERR "IOMMU: reserve iova failed\n");
+		return -ENOMEM;
+	}
+
+	pr_debug("Mapping reserved region %llx-%llx for domain %d\n",
+		 start, end, domain->id);
+	/*
+	 * RMRR range might have overlap with physical memory range,
+	 * clear it first
+	 */
+	dma_pte_clear_range(domain, first_vpfn, last_vpfn);
+
+	return domain_pfn_mapping(domain, first_vpfn, first_vpfn,
+				  last_vpfn - first_vpfn + 1,
+				  DMA_PTE_READ|DMA_PTE_WRITE);
+}
+
+static int iommu_prepare_identity_map(struct pci_dev *pdev,
+				      unsigned long long start,
+				      unsigned long long end)
+{
+	struct dmar_domain *domain;
+	int ret;
+
+	domain = get_domain_for_dev(pdev, DEFAULT_DOMAIN_ADDRESS_WIDTH);
+	if (!domain)
+		return -ENOMEM;
+
+	/* For _hardware_ passthrough, don't bother. But for software
+	   passthrough, we do it anyway -- it may indicate a memory
+	   range which is reserved in E820, so which didn't get set
+	   up to start with in si_domain */
+	if (domain == si_domain && hw_pass_through) {
+		printk("Ignoring identity map for HW passthrough device %s [0x%Lx - 0x%Lx]\n",
+		       pci_name(pdev), start, end);
+		return 0;
+	}
+
+	printk(KERN_INFO
+	       "IOMMU: Setting identity map for device %s [0x%Lx - 0x%Lx]\n",
+	       pci_name(pdev), start, end);
+	
+	if (end < start) {
+		WARN(1, "Your BIOS is broken; RMRR ends before it starts!\n"
+			"BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+			dmi_get_system_info(DMI_BIOS_VENDOR),
+			dmi_get_system_info(DMI_BIOS_VERSION),
+		     dmi_get_system_info(DMI_PRODUCT_VERSION));
+		ret = -EIO;
+		goto error;
+	}
+
+	if (end >> agaw_to_width(domain->agaw)) {
+		WARN(1, "Your BIOS is broken; RMRR exceeds permitted address width (%d bits)\n"
+		     "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+		     agaw_to_width(domain->agaw),
+		     dmi_get_system_info(DMI_BIOS_VENDOR),
+		     dmi_get_system_info(DMI_BIOS_VERSION),
+		     dmi_get_system_info(DMI_PRODUCT_VERSION));
+		ret = -EIO;
+		goto error;
+	}
+
+	ret = iommu_domain_identity_map(domain, start, end);
+	if (ret)
+		goto error;
+
+	/* context entry init */
+	ret = domain_context_mapping(domain, pdev, CONTEXT_TT_MULTI_LEVEL);
+	if (ret)
+		goto error;
+
+	return 0;
+
+ error:
+	domain_exit(domain);
+	return ret;
+}
+
+static inline int iommu_prepare_rmrr_dev(struct dmar_rmrr_unit *rmrr,
+	struct pci_dev *pdev)
+{
+	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
+		return 0;
+	return iommu_prepare_identity_map(pdev, rmrr->base_address,
+		rmrr->end_address);
+}
+
+#ifdef CONFIG_DMAR_FLOPPY_WA
+static inline void iommu_prepare_isa(void)
+{
+	struct pci_dev *pdev;
+	int ret;
+
+	pdev = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, NULL);
+	if (!pdev)
+		return;
+
+	printk(KERN_INFO "IOMMU: Prepare 0-16MiB unity mapping for LPC\n");
+	ret = iommu_prepare_identity_map(pdev, 0, 16*1024*1024 - 1);
+
+	if (ret)
+		printk(KERN_ERR "IOMMU: Failed to create 0-16MiB identity map; "
+		       "floppy might not work\n");
+
+}
+#else
+static inline void iommu_prepare_isa(void)
+{
+	return;
+}
+#endif /* !CONFIG_DMAR_FLPY_WA */
+
+static int md_domain_init(struct dmar_domain *domain, int guest_width);
+
+static int __init si_domain_work_fn(unsigned long start_pfn,
+				    unsigned long end_pfn, void *datax)
+{
+	int *ret = datax;
+
+	*ret = iommu_domain_identity_map(si_domain,
+					 (uint64_t)start_pfn << PAGE_SHIFT,
+					 (uint64_t)end_pfn << PAGE_SHIFT);
+	return *ret;
+
+}
+
+static int __init si_domain_init(int hw)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu;
+	int nid, ret = 0;
+
+	si_domain = alloc_domain();
+	if (!si_domain)
+		return -EFAULT;
+
+	pr_debug("Identity mapping domain is domain %d\n", si_domain->id);
+
+	for_each_active_iommu(iommu, drhd) {
+		ret = iommu_attach_domain(si_domain, iommu);
+		if (ret) {
+			domain_exit(si_domain);
+			return -EFAULT;
+		}
+	}
+
+	if (md_domain_init(si_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
+		domain_exit(si_domain);
+		return -EFAULT;
+	}
+
+	si_domain->flags = DOMAIN_FLAG_STATIC_IDENTITY;
+
+	if (hw)
+		return 0;
+
+	for_each_online_node(nid) {
+		work_with_active_regions(nid, si_domain_work_fn, &ret);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void domain_remove_one_dev_info(struct dmar_domain *domain,
+					  struct pci_dev *pdev);
+static int identity_mapping(struct pci_dev *pdev)
+{
+	struct device_domain_info *info;
+
+	if (likely(!iommu_identity_mapping))
+		return 0;
+
+	info = pdev->dev.archdata.iommu;
+	if (info && info != DUMMY_DEVICE_DOMAIN_INFO)
+		return (info->domain == si_domain);
+
+	return 0;
+}
+
+static int domain_add_dev_info(struct dmar_domain *domain,
+			       struct pci_dev *pdev,
+			       int translation)
+{
+	struct device_domain_info *info;
+	unsigned long flags;
+	int ret;
+
+	info = alloc_devinfo_mem();
+	if (!info)
+		return -ENOMEM;
+
+	ret = domain_context_mapping(domain, pdev, translation);
+	if (ret) {
+		free_devinfo_mem(info);
+		return ret;
+	}
+
+	info->segment = pci_domain_nr(pdev->bus);
+	info->bus = pdev->bus->number;
+	info->devfn = pdev->devfn;
+	info->dev = pdev;
+	info->domain = domain;
+
+	spin_lock_irqsave(&device_domain_lock, flags);
+	list_add(&info->link, &domain->devices);
+	list_add(&info->global, &device_domain_list);
+	pdev->dev.archdata.iommu = info;
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+
+	return 0;
+}
+
+static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
+{
+	if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
+		return 1;
+
+	if ((iommu_identity_mapping & IDENTMAP_GFX) && IS_GFX_DEVICE(pdev))
+		return 1;
+
+	if (!(iommu_identity_mapping & IDENTMAP_ALL))
+		return 0;
+
+	/*
+	 * We want to start off with all devices in the 1:1 domain, and
+	 * take them out later if we find they can't access all of memory.
+	 *
+	 * However, we can't do this for PCI devices behind bridges,
+	 * because all PCI devices behind the same bridge will end up
+	 * with the same source-id on their transactions.
+	 *
+	 * Practically speaking, we can't change things around for these
+	 * devices at run-time, because we can't be sure there'll be no
+	 * DMA transactions in flight for any of their siblings.
+	 * 
+	 * So PCI devices (unless they're on the root bus) as well as
+	 * their parent PCI-PCI or PCIe-PCI bridges must be left _out_ of
+	 * the 1:1 domain, just in _case_ one of their siblings turns out
+	 * not to be able to map all of memory.
+	 */
+	if (!pci_is_pcie(pdev)) {
+		if (!pci_is_root_bus(pdev->bus))
+			return 0;
+		if (pdev->class >> 8 == PCI_CLASS_BRIDGE_PCI)
+			return 0;
+	} else if (pdev->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
+		return 0;
+
+	/* 
+	 * At boot time, we don't yet know if devices will be 64-bit capable.
+	 * Assume that they will -- if they turn out not to be, then we can 
+	 * take them out of the 1:1 domain later.
+	 */
+	if (!startup) {
+		/*
+		 * If the device's dma_mask is less than the system's memory
+		 * size then this is not a candidate for identity mapping.
+		 */
+		u64 dma_mask = pdev->dma_mask;
+
+		if (pdev->dev.coherent_dma_mask &&
+		    pdev->dev.coherent_dma_mask < dma_mask)
+			dma_mask = pdev->dev.coherent_dma_mask;
+
+		return dma_mask >= dma_get_required_mask(&pdev->dev);
+	}
+
+	return 1;
+}
+
+static int __init iommu_prepare_static_identity_mapping(int hw)
+{
+	struct pci_dev *pdev = NULL;
+	int ret;
+
+	ret = si_domain_init(hw);
+	if (ret)
+		return -EFAULT;
+
+	for_each_pci_dev(pdev) {
+		/* Skip Host/PCI Bridge devices */
+		if (IS_BRIDGE_HOST_DEVICE(pdev))
+			continue;
+		if (iommu_should_identity_map(pdev, 1)) {
+			printk(KERN_INFO "IOMMU: %s identity mapping for device %s\n",
+			       hw ? "hardware" : "software", pci_name(pdev));
+
+			ret = domain_add_dev_info(si_domain, pdev,
+						     hw ? CONTEXT_TT_PASS_THROUGH :
+						     CONTEXT_TT_MULTI_LEVEL);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int __init init_dmars(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct dmar_rmrr_unit *rmrr;
+	struct pci_dev *pdev;
+	struct intel_iommu *iommu;
+	int i, ret;
+
+	/*
+	 * for each drhd
+	 *    allocate root
+	 *    initialize and program root entry to not present
+	 * endfor
+	 */
+	for_each_drhd_unit(drhd) {
+		g_num_of_iommus++;
+		/*
+		 * lock not needed as this is only incremented in the single
+		 * threaded kernel __init code path all other access are read
+		 * only
+		 */
+	}
+
+	g_iommus = kcalloc(g_num_of_iommus, sizeof(struct intel_iommu *),
+			GFP_KERNEL);
+	if (!g_iommus) {
+		printk(KERN_ERR "Allocating global iommu array failed\n");
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	deferred_flush = kzalloc(g_num_of_iommus *
+		sizeof(struct deferred_flush_tables), GFP_KERNEL);
+	if (!deferred_flush) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+
+		iommu = drhd->iommu;
+		g_iommus[iommu->seq_id] = iommu;
+
+		ret = iommu_init_domains(iommu);
+		if (ret)
+			goto error;
+
+		/*
+		 * TBD:
+		 * we could share the same root & context tables
+		 * among all IOMMU's. Need to Split it later.
+		 */
+		ret = iommu_alloc_root_entry(iommu);
+		if (ret) {
+			printk(KERN_ERR "IOMMU: allocate root entry failed\n");
+			goto error;
+		}
+		if (!ecap_pass_through(iommu->ecap))
+			hw_pass_through = 0;
+	}
+
+	/*
+	 * Start from the sane iommu hardware state.
+	 */
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+
+		iommu = drhd->iommu;
+
+		/*
+		 * If the queued invalidation is already initialized by us
+		 * (for example, while enabling interrupt-remapping) then
+		 * we got the things already rolling from a sane state.
+		 */
+		if (iommu->qi)
+			continue;
+
+		/*
+		 * Clear any previous faults.
+		 */
+		dmar_fault(-1, iommu);
+		/*
+		 * Disable queued invalidation if supported and already enabled
+		 * before OS handover.
+		 */
+		dmar_disable_qi(iommu);
+	}
+
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+
+		iommu = drhd->iommu;
+
+		if (dmar_enable_qi(iommu)) {
+			/*
+			 * Queued Invalidate not enabled, use Register Based
+			 * Invalidate
+			 */
+			iommu->flush.flush_context = __iommu_flush_context;
+			iommu->flush.flush_iotlb = __iommu_flush_iotlb;
+			printk(KERN_INFO "IOMMU %d 0x%Lx: using Register based "
+			       "invalidation\n",
+				iommu->seq_id,
+			       (unsigned long long)drhd->reg_base_addr);
+		} else {
+			iommu->flush.flush_context = qi_flush_context;
+			iommu->flush.flush_iotlb = qi_flush_iotlb;
+			printk(KERN_INFO "IOMMU %d 0x%Lx: using Queued "
+			       "invalidation\n",
+				iommu->seq_id,
+			       (unsigned long long)drhd->reg_base_addr);
+		}
+	}
+
+	if (iommu_pass_through)
+		iommu_identity_mapping |= IDENTMAP_ALL;
+
+#ifdef CONFIG_DMAR_BROKEN_GFX_WA
+	iommu_identity_mapping |= IDENTMAP_GFX;
+#endif
+
+	check_tylersburg_isoch();
+
+	/*
+	 * If pass through is not set or not enabled, setup context entries for
+	 * identity mappings for rmrr, gfx, and isa and may fall back to static
+	 * identity mapping if iommu_identity_mapping is set.
+	 */
+	if (iommu_identity_mapping) {
+		ret = iommu_prepare_static_identity_mapping(hw_pass_through);
+		if (ret) {
+			printk(KERN_CRIT "Failed to setup IOMMU pass-through\n");
+			goto error;
+		}
+	}
+	/*
+	 * For each rmrr
+	 *   for each dev attached to rmrr
+	 *   do
+	 *     locate drhd for dev, alloc domain for dev
+	 *     allocate free domain
+	 *     allocate page table entries for rmrr
+	 *     if context not allocated for bus
+	 *           allocate and init context
+	 *           set present in root table for this bus
+	 *     init context with domain, translation etc
+	 *    endfor
+	 * endfor
+	 */
+	printk(KERN_INFO "IOMMU: Setting RMRR:\n");
+	for_each_rmrr_units(rmrr) {
+		for (i = 0; i < rmrr->devices_cnt; i++) {
+			pdev = rmrr->devices[i];
+			/*
+			 * some BIOS lists non-exist devices in DMAR
+			 * table.
+			 */
+			if (!pdev)
+				continue;
+			ret = iommu_prepare_rmrr_dev(rmrr, pdev);
+			if (ret)
+				printk(KERN_ERR
+				       "IOMMU: mapping reserved region failed\n");
+		}
+	}
+
+	iommu_prepare_isa();
+
+	/*
+	 * for each drhd
+	 *   enable fault log
+	 *   global invalidate context cache
+	 *   global invalidate iotlb
+	 *   enable translation
+	 */
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored) {
+			/*
+			 * we always have to disable PMRs or DMA may fail on
+			 * this device
+			 */
+			if (force_on)
+				iommu_disable_protect_mem_regions(drhd->iommu);
+			continue;
+		}
+		iommu = drhd->iommu;
+
+		iommu_flush_write_buffer(iommu);
+
+		ret = dmar_set_interrupt(iommu);
+		if (ret)
+			goto error;
+
+		iommu_set_root_entry(iommu);
+
+		iommu->flush.flush_context(iommu, 0, 0, 0, DMA_CCMD_GLOBAL_INVL);
+		iommu->flush.flush_iotlb(iommu, 0, 0, 0, DMA_TLB_GLOBAL_FLUSH);
+
+		ret = iommu_enable_translation(iommu);
+		if (ret)
+			goto error;
+
+		iommu_disable_protect_mem_regions(iommu);
+	}
+
+	return 0;
+error:
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+		iommu = drhd->iommu;
+		free_iommu(iommu);
+	}
+	kfree(g_iommus);
+	return ret;
+}
+
+/* This takes a number of _MM_ pages, not VTD pages */
+static struct iova *intel_alloc_iova(struct device *dev,
+				     struct dmar_domain *domain,
+				     unsigned long nrpages, uint64_t dma_mask)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct iova *iova = NULL;
+
+	/* Restrict dma_mask to the width that the iommu can handle */
+	dma_mask = min_t(uint64_t, DOMAIN_MAX_ADDR(domain->gaw), dma_mask);
+
+	if (!dmar_forcedac && dma_mask > DMA_BIT_MASK(32)) {
+		/*
+		 * First try to allocate an io virtual address in
+		 * DMA_BIT_MASK(32) and if that fails then try allocating
+		 * from higher range
+		 */
+		iova = alloc_iova(&domain->iovad, nrpages,
+				  IOVA_PFN(DMA_BIT_MASK(32)), 1);
+		if (iova)
+			return iova;
+	}
+	iova = alloc_iova(&domain->iovad, nrpages, IOVA_PFN(dma_mask), 1);
+	if (unlikely(!iova)) {
+		printk(KERN_ERR "Allocating %ld-page iova for %s failed",
+		       nrpages, pci_name(pdev));
+		return NULL;
+	}
+
+	return iova;
+}
+
+static struct dmar_domain *__get_valid_domain_for_dev(struct pci_dev *pdev)
+{
+	struct dmar_domain *domain;
+	int ret;
+
+	domain = get_domain_for_dev(pdev,
+			DEFAULT_DOMAIN_ADDRESS_WIDTH);
+	if (!domain) {
+		printk(KERN_ERR
+			"Allocating domain for %s failed", pci_name(pdev));
+		return NULL;
+	}
+
+	/* make sure context mapping is ok */
+	if (unlikely(!domain_context_mapped(pdev))) {
+		ret = domain_context_mapping(domain, pdev,
+					     CONTEXT_TT_MULTI_LEVEL);
+		if (ret) {
+			printk(KERN_ERR
+				"Domain context map for %s failed",
+				pci_name(pdev));
+			return NULL;
+		}
+	}
+
+	return domain;
+}
+
+static inline struct dmar_domain *get_valid_domain_for_dev(struct pci_dev *dev)
+{
+	struct device_domain_info *info;
+
+	/* No lock here, assumes no domain exit in normal case */
+	info = dev->dev.archdata.iommu;
+	if (likely(info))
+		return info->domain;
+
+	return __get_valid_domain_for_dev(dev);
+}
+
+static int iommu_dummy(struct pci_dev *pdev)
+{
+	return pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO;
+}
+
+/* Check if the pdev needs to go through non-identity map and unmap process.*/
+static int iommu_no_mapping(struct device *dev)
+{
+	struct pci_dev *pdev;
+	int found;
+
+	if (unlikely(dev->bus != &pci_bus_type))
+		return 1;
+
+	pdev = to_pci_dev(dev);
+	if (iommu_dummy(pdev))
+		return 1;
+
+	if (!iommu_identity_mapping)
+		return 0;
+
+	found = identity_mapping(pdev);
+	if (found) {
+		if (iommu_should_identity_map(pdev, 0))
+			return 1;
+		else {
+			/*
+			 * 32 bit DMA is removed from si_domain and fall back
+			 * to non-identity mapping.
+			 */
+			domain_remove_one_dev_info(si_domain, pdev);
+			printk(KERN_INFO "32bit %s uses non-identity mapping\n",
+			       pci_name(pdev));
+			return 0;
+		}
+	} else {
+		/*
+		 * In case of a detached 64 bit DMA device from vm, the device
+		 * is put into si_domain for identity mapping.
+		 */
+		if (iommu_should_identity_map(pdev, 0)) {
+			int ret;
+			ret = domain_add_dev_info(si_domain, pdev,
+						  hw_pass_through ?
+						  CONTEXT_TT_PASS_THROUGH :
+						  CONTEXT_TT_MULTI_LEVEL);
+			if (!ret) {
+				printk(KERN_INFO "64bit %s uses identity mapping\n",
+				       pci_name(pdev));
+				return 1;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static dma_addr_t __intel_map_single(struct device *hwdev, phys_addr_t paddr,
+				     size_t size, int dir, u64 dma_mask)
+{
+	struct pci_dev *pdev = to_pci_dev(hwdev);
+	struct dmar_domain *domain;
+	phys_addr_t start_paddr;
+	struct iova *iova;
+	int prot = 0;
+	int ret;
+	struct intel_iommu *iommu;
+	unsigned long paddr_pfn = paddr >> PAGE_SHIFT;
+
+	BUG_ON(dir == DMA_NONE);
+
+	if (iommu_no_mapping(hwdev))
+		return paddr;
+
+	domain = get_valid_domain_for_dev(pdev);
+	if (!domain)
+		return 0;
+
+	iommu = domain_get_iommu(domain);
+	size = aligned_nrpages(paddr, size);
+
+	iova = intel_alloc_iova(hwdev, domain, dma_to_mm_pfn(size), dma_mask);
+	if (!iova)
+		goto error;
+
+	/*
+	 * Check if DMAR supports zero-length reads on write only
+	 * mappings..
+	 */
+	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL || \
+			!cap_zlr(iommu->cap))
+		prot |= DMA_PTE_READ;
+	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+		prot |= DMA_PTE_WRITE;
+	/*
+	 * paddr - (paddr + size) might be partial page, we should map the whole
+	 * page.  Note: if two part of one page are separately mapped, we
+	 * might have two guest_addr mapping to the same host paddr, but this
+	 * is not a big problem
+	 */
+	ret = domain_pfn_mapping(domain, mm_to_dma_pfn(iova->pfn_lo),
+				 mm_to_dma_pfn(paddr_pfn), size, prot);
+	if (ret)
+		goto error;
+
+	/* it's a non-present to present mapping. Only flush if caching mode */
+	if (cap_caching_mode(iommu->cap))
+		iommu_flush_iotlb_psi(iommu, domain->id, mm_to_dma_pfn(iova->pfn_lo), size, 1);
+	else
+		iommu_flush_write_buffer(iommu);
+
+	start_paddr = (phys_addr_t)iova->pfn_lo << PAGE_SHIFT;
+	start_paddr += paddr & ~PAGE_MASK;
+	return start_paddr;
+
+error:
+	if (iova)
+		__free_iova(&domain->iovad, iova);
+	printk(KERN_ERR"Device %s request: %zx@%llx dir %d --- failed\n",
+		pci_name(pdev), size, (unsigned long long)paddr, dir);
+	return 0;
+}
+
+static dma_addr_t intel_map_page(struct device *dev, struct page *page,
+				 unsigned long offset, size_t size,
+				 enum dma_data_direction dir,
+				 struct dma_attrs *attrs)
+{
+	return __intel_map_single(dev, page_to_phys(page) + offset, size,
+				  dir, to_pci_dev(dev)->dma_mask);
+}
+
+static void flush_unmaps(void)
+{
+	int i, j;
+
+	timer_on = 0;
+
+	/* just flush them all */
+	for (i = 0; i < g_num_of_iommus; i++) {
+		struct intel_iommu *iommu = g_iommus[i];
+		if (!iommu)
+			continue;
+
+		if (!deferred_flush[i].next)
+			continue;
+
+		/* In caching mode, global flushes turn emulation expensive */
+		if (!cap_caching_mode(iommu->cap))
+			iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+					 DMA_TLB_GLOBAL_FLUSH);
+		for (j = 0; j < deferred_flush[i].next; j++) {
+			unsigned long mask;
+			struct iova *iova = deferred_flush[i].iova[j];
+			struct dmar_domain *domain = deferred_flush[i].domain[j];
+
+			/* On real hardware multiple invalidations are expensive */
+			if (cap_caching_mode(iommu->cap))
+				iommu_flush_iotlb_psi(iommu, domain->id,
+				iova->pfn_lo, iova->pfn_hi - iova->pfn_lo + 1, 0);
+			else {
+				mask = ilog2(mm_to_dma_pfn(iova->pfn_hi - iova->pfn_lo + 1));
+				iommu_flush_dev_iotlb(deferred_flush[i].domain[j],
+						(uint64_t)iova->pfn_lo << PAGE_SHIFT, mask);
+			}
+			__free_iova(&deferred_flush[i].domain[j]->iovad, iova);
+		}
+		deferred_flush[i].next = 0;
+	}
+
+	list_size = 0;
+}
+
+static void flush_unmaps_timeout(unsigned long data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&async_umap_flush_lock, flags);
+	flush_unmaps();
+	spin_unlock_irqrestore(&async_umap_flush_lock, flags);
+}
+
+static void add_unmap(struct dmar_domain *dom, struct iova *iova)
+{
+	unsigned long flags;
+	int next, iommu_id;
+	struct intel_iommu *iommu;
+
+	spin_lock_irqsave(&async_umap_flush_lock, flags);
+	if (list_size == HIGH_WATER_MARK)
+		flush_unmaps();
+
+	iommu = domain_get_iommu(dom);
+	iommu_id = iommu->seq_id;
+
+	next = deferred_flush[iommu_id].next;
+	deferred_flush[iommu_id].domain[next] = dom;
+	deferred_flush[iommu_id].iova[next] = iova;
+	deferred_flush[iommu_id].next++;
+
+	if (!timer_on) {
+		mod_timer(&unmap_timer, jiffies + msecs_to_jiffies(10));
+		timer_on = 1;
+	}
+	list_size++;
+	spin_unlock_irqrestore(&async_umap_flush_lock, flags);
+}
+
+static void intel_unmap_page(struct device *dev, dma_addr_t dev_addr,
+			     size_t size, enum dma_data_direction dir,
+			     struct dma_attrs *attrs)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct dmar_domain *domain;
+	unsigned long start_pfn, last_pfn;
+	struct iova *iova;
+	struct intel_iommu *iommu;
+
+	if (iommu_no_mapping(dev))
+		return;
+
+	domain = find_domain(pdev);
+	BUG_ON(!domain);
+
+	iommu = domain_get_iommu(domain);
+
+	iova = find_iova(&domain->iovad, IOVA_PFN(dev_addr));
+	if (WARN_ONCE(!iova, "Driver unmaps unmatched page at PFN %llx\n",
+		      (unsigned long long)dev_addr))
+		return;
+
+	start_pfn = mm_to_dma_pfn(iova->pfn_lo);
+	last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+
+	pr_debug("Device %s unmapping: pfn %lx-%lx\n",
+		 pci_name(pdev), start_pfn, last_pfn);
+
+	/*  clear the whole page */
+	dma_pte_clear_range(domain, start_pfn, last_pfn);
+
+	/* free page tables */
+	dma_pte_free_pagetable(domain, start_pfn, last_pfn);
+
+	if (intel_iommu_strict) {
+		iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
+				      last_pfn - start_pfn + 1, 0);
+		/* free iova */
+		__free_iova(&domain->iovad, iova);
+	} else {
+		add_unmap(domain, iova);
+		/*
+		 * queue up the release of the unmap to save the 1/6th of the
+		 * cpu used up by the iotlb flush operation...
+		 */
+	}
+}
+
+static void *intel_alloc_coherent(struct device *hwdev, size_t size,
+				  dma_addr_t *dma_handle, gfp_t flags)
+{
+	void *vaddr;
+	int order;
+
+	size = PAGE_ALIGN(size);
+	order = get_order(size);
+
+	if (!iommu_no_mapping(hwdev))
+		flags &= ~(GFP_DMA | GFP_DMA32);
+	else if (hwdev->coherent_dma_mask < dma_get_required_mask(hwdev)) {
+		if (hwdev->coherent_dma_mask < DMA_BIT_MASK(32))
+			flags |= GFP_DMA;
+		else
+			flags |= GFP_DMA32;
+	}
+
+	vaddr = (void *)__get_free_pages(flags, order);
+	if (!vaddr)
+		return NULL;
+	memset(vaddr, 0, size);
+
+	*dma_handle = __intel_map_single(hwdev, virt_to_bus(vaddr), size,
+					 DMA_BIDIRECTIONAL,
+					 hwdev->coherent_dma_mask);
+	if (*dma_handle)
+		return vaddr;
+	free_pages((unsigned long)vaddr, order);
+	return NULL;
+}
+
+static void intel_free_coherent(struct device *hwdev, size_t size, void *vaddr,
+				dma_addr_t dma_handle)
+{
+	int order;
+
+	size = PAGE_ALIGN(size);
+	order = get_order(size);
+
+	intel_unmap_page(hwdev, dma_handle, size, DMA_BIDIRECTIONAL, NULL);
+	free_pages((unsigned long)vaddr, order);
+}
+
+static void intel_unmap_sg(struct device *hwdev, struct scatterlist *sglist,
+			   int nelems, enum dma_data_direction dir,
+			   struct dma_attrs *attrs)
+{
+	struct pci_dev *pdev = to_pci_dev(hwdev);
+	struct dmar_domain *domain;
+	unsigned long start_pfn, last_pfn;
+	struct iova *iova;
+	struct intel_iommu *iommu;
+
+	if (iommu_no_mapping(hwdev))
+		return;
+
+	domain = find_domain(pdev);
+	BUG_ON(!domain);
+
+	iommu = domain_get_iommu(domain);
+
+	iova = find_iova(&domain->iovad, IOVA_PFN(sglist[0].dma_address));
+	if (WARN_ONCE(!iova, "Driver unmaps unmatched sglist at PFN %llx\n",
+		      (unsigned long long)sglist[0].dma_address))
+		return;
+
+	start_pfn = mm_to_dma_pfn(iova->pfn_lo);
+	last_pfn = mm_to_dma_pfn(iova->pfn_hi + 1) - 1;
+
+	/*  clear the whole page */
+	dma_pte_clear_range(domain, start_pfn, last_pfn);
+
+	/* free page tables */
+	dma_pte_free_pagetable(domain, start_pfn, last_pfn);
+
+	if (intel_iommu_strict) {
+		iommu_flush_iotlb_psi(iommu, domain->id, start_pfn,
+				      last_pfn - start_pfn + 1, 0);
+		/* free iova */
+		__free_iova(&domain->iovad, iova);
+	} else {
+		add_unmap(domain, iova);
+		/*
+		 * queue up the release of the unmap to save the 1/6th of the
+		 * cpu used up by the iotlb flush operation...
+		 */
+	}
+}
+
+static int intel_nontranslate_map_sg(struct device *hddev,
+	struct scatterlist *sglist, int nelems, int dir)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i) {
+		BUG_ON(!sg_page(sg));
+		sg->dma_address = page_to_phys(sg_page(sg)) + sg->offset;
+		sg->dma_length = sg->length;
+	}
+	return nelems;
+}
+
+static int intel_map_sg(struct device *hwdev, struct scatterlist *sglist, int nelems,
+			enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+	int i;
+	struct pci_dev *pdev = to_pci_dev(hwdev);
+	struct dmar_domain *domain;
+	size_t size = 0;
+	int prot = 0;
+	struct iova *iova = NULL;
+	int ret;
+	struct scatterlist *sg;
+	unsigned long start_vpfn;
+	struct intel_iommu *iommu;
+
+	BUG_ON(dir == DMA_NONE);
+	if (iommu_no_mapping(hwdev))
+		return intel_nontranslate_map_sg(hwdev, sglist, nelems, dir);
+
+	domain = get_valid_domain_for_dev(pdev);
+	if (!domain)
+		return 0;
+
+	iommu = domain_get_iommu(domain);
+
+	for_each_sg(sglist, sg, nelems, i)
+		size += aligned_nrpages(sg->offset, sg->length);
+
+	iova = intel_alloc_iova(hwdev, domain, dma_to_mm_pfn(size),
+				pdev->dma_mask);
+	if (!iova) {
+		sglist->dma_length = 0;
+		return 0;
+	}
+
+	/*
+	 * Check if DMAR supports zero-length reads on write only
+	 * mappings..
+	 */
+	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL || \
+			!cap_zlr(iommu->cap))
+		prot |= DMA_PTE_READ;
+	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
+		prot |= DMA_PTE_WRITE;
+
+	start_vpfn = mm_to_dma_pfn(iova->pfn_lo);
+
+	ret = domain_sg_mapping(domain, start_vpfn, sglist, size, prot);
+	if (unlikely(ret)) {
+		/*  clear the page */
+		dma_pte_clear_range(domain, start_vpfn,
+				    start_vpfn + size - 1);
+		/* free page tables */
+		dma_pte_free_pagetable(domain, start_vpfn,
+				       start_vpfn + size - 1);
+		/* free iova */
+		__free_iova(&domain->iovad, iova);
+		return 0;
+	}
+
+	/* it's a non-present to present mapping. Only flush if caching mode */
+	if (cap_caching_mode(iommu->cap))
+		iommu_flush_iotlb_psi(iommu, domain->id, start_vpfn, size, 1);
+	else
+		iommu_flush_write_buffer(iommu);
+
+	return nelems;
+}
+
+static int intel_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return !dma_addr;
+}
+
+struct dma_map_ops intel_dma_ops = {
+	.alloc_coherent = intel_alloc_coherent,
+	.free_coherent = intel_free_coherent,
+	.map_sg = intel_map_sg,
+	.unmap_sg = intel_unmap_sg,
+	.map_page = intel_map_page,
+	.unmap_page = intel_unmap_page,
+	.mapping_error = intel_mapping_error,
+};
+
+static inline int iommu_domain_cache_init(void)
+{
+	int ret = 0;
+
+	iommu_domain_cache = kmem_cache_create("iommu_domain",
+					 sizeof(struct dmar_domain),
+					 0,
+					 SLAB_HWCACHE_ALIGN,
+
+					 NULL);
+	if (!iommu_domain_cache) {
+		printk(KERN_ERR "Couldn't create iommu_domain cache\n");
+		ret = -ENOMEM;
+	}
+
+	return ret;
+}
+
+static inline int iommu_devinfo_cache_init(void)
+{
+	int ret = 0;
+
+	iommu_devinfo_cache = kmem_cache_create("iommu_devinfo",
+					 sizeof(struct device_domain_info),
+					 0,
+					 SLAB_HWCACHE_ALIGN,
+					 NULL);
+	if (!iommu_devinfo_cache) {
+		printk(KERN_ERR "Couldn't create devinfo cache\n");
+		ret = -ENOMEM;
+	}
+
+	return ret;
+}
+
+static inline int iommu_iova_cache_init(void)
+{
+	int ret = 0;
+
+	iommu_iova_cache = kmem_cache_create("iommu_iova",
+					 sizeof(struct iova),
+					 0,
+					 SLAB_HWCACHE_ALIGN,
+					 NULL);
+	if (!iommu_iova_cache) {
+		printk(KERN_ERR "Couldn't create iova cache\n");
+		ret = -ENOMEM;
+	}
+
+	return ret;
+}
+
+static int __init iommu_init_mempool(void)
+{
+	int ret;
+	ret = iommu_iova_cache_init();
+	if (ret)
+		return ret;
+
+	ret = iommu_domain_cache_init();
+	if (ret)
+		goto domain_error;
+
+	ret = iommu_devinfo_cache_init();
+	if (!ret)
+		return ret;
+
+	kmem_cache_destroy(iommu_domain_cache);
+domain_error:
+	kmem_cache_destroy(iommu_iova_cache);
+
+	return -ENOMEM;
+}
+
+static void __init iommu_exit_mempool(void)
+{
+	kmem_cache_destroy(iommu_devinfo_cache);
+	kmem_cache_destroy(iommu_domain_cache);
+	kmem_cache_destroy(iommu_iova_cache);
+
+}
+
+static void quirk_ioat_snb_local_iommu(struct pci_dev *pdev)
+{
+	struct dmar_drhd_unit *drhd;
+	u32 vtbar;
+	int rc;
+
+	/* We know that this device on this chipset has its own IOMMU.
+	 * If we find it under a different IOMMU, then the BIOS is lying
+	 * to us. Hope that the IOMMU for this device is actually
+	 * disabled, and it needs no translation...
+	 */
+	rc = pci_bus_read_config_dword(pdev->bus, PCI_DEVFN(0, 0), 0xb0, &vtbar);
+	if (rc) {
+		/* "can't" happen */
+		dev_info(&pdev->dev, "failed to run vt-d quirk\n");
+		return;
+	}
+	vtbar &= 0xffff0000;
+
+	/* we know that the this iommu should be at offset 0xa000 from vtbar */
+	drhd = dmar_find_matched_drhd_unit(pdev);
+	if (WARN_TAINT_ONCE(!drhd || drhd->reg_base_addr - vtbar != 0xa000,
+			    TAINT_FIRMWARE_WORKAROUND,
+			    "BIOS assigned incorrect VT-d unit for Intel(R) QuickData Technology device\n"))
+		pdev->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
+}
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB, quirk_ioat_snb_local_iommu);
+
+static void __init init_no_remapping_devices(void)
+{
+	struct dmar_drhd_unit *drhd;
+
+	for_each_drhd_unit(drhd) {
+		if (!drhd->include_all) {
+			int i;
+			for (i = 0; i < drhd->devices_cnt; i++)
+				if (drhd->devices[i] != NULL)
+					break;
+			/* ignore DMAR unit if no pci devices exist */
+			if (i == drhd->devices_cnt)
+				drhd->ignored = 1;
+		}
+	}
+
+	if (dmar_map_gfx)
+		return;
+
+	for_each_drhd_unit(drhd) {
+		int i;
+		if (drhd->ignored || drhd->include_all)
+			continue;
+
+		for (i = 0; i < drhd->devices_cnt; i++)
+			if (drhd->devices[i] &&
+				!IS_GFX_DEVICE(drhd->devices[i]))
+				break;
+
+		if (i < drhd->devices_cnt)
+			continue;
+
+		/* bypass IOMMU if it is just for gfx devices */
+		drhd->ignored = 1;
+		for (i = 0; i < drhd->devices_cnt; i++) {
+			if (!drhd->devices[i])
+				continue;
+			drhd->devices[i]->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
+		}
+	}
+}
+
+#ifdef CONFIG_SUSPEND
+static int init_iommu_hw(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu = NULL;
+
+	for_each_active_iommu(iommu, drhd)
+		if (iommu->qi)
+			dmar_reenable_qi(iommu);
+
+	for_each_iommu(iommu, drhd) {
+		if (drhd->ignored) {
+			/*
+			 * we always have to disable PMRs or DMA may fail on
+			 * this device
+			 */
+			if (force_on)
+				iommu_disable_protect_mem_regions(iommu);
+			continue;
+		}
+	
+		iommu_flush_write_buffer(iommu);
+
+		iommu_set_root_entry(iommu);
+
+		iommu->flush.flush_context(iommu, 0, 0, 0,
+					   DMA_CCMD_GLOBAL_INVL);
+		iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+					 DMA_TLB_GLOBAL_FLUSH);
+		if (iommu_enable_translation(iommu))
+			return 1;
+		iommu_disable_protect_mem_regions(iommu);
+	}
+
+	return 0;
+}
+
+static void iommu_flush_all(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu;
+
+	for_each_active_iommu(iommu, drhd) {
+		iommu->flush.flush_context(iommu, 0, 0, 0,
+					   DMA_CCMD_GLOBAL_INVL);
+		iommu->flush.flush_iotlb(iommu, 0, 0, 0,
+					 DMA_TLB_GLOBAL_FLUSH);
+	}
+}
+
+static int iommu_suspend(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu = NULL;
+	unsigned long flag;
+
+	for_each_active_iommu(iommu, drhd) {
+		iommu->iommu_state = kzalloc(sizeof(u32) * MAX_SR_DMAR_REGS,
+						 GFP_ATOMIC);
+		if (!iommu->iommu_state)
+			goto nomem;
+	}
+
+	iommu_flush_all();
+
+	for_each_active_iommu(iommu, drhd) {
+		iommu_disable_translation(iommu);
+
+		spin_lock_irqsave(&iommu->register_lock, flag);
+
+		iommu->iommu_state[SR_DMAR_FECTL_REG] =
+			readl(iommu->reg + DMAR_FECTL_REG);
+		iommu->iommu_state[SR_DMAR_FEDATA_REG] =
+			readl(iommu->reg + DMAR_FEDATA_REG);
+		iommu->iommu_state[SR_DMAR_FEADDR_REG] =
+			readl(iommu->reg + DMAR_FEADDR_REG);
+		iommu->iommu_state[SR_DMAR_FEUADDR_REG] =
+			readl(iommu->reg + DMAR_FEUADDR_REG);
+
+		spin_unlock_irqrestore(&iommu->register_lock, flag);
+	}
+	return 0;
+
+nomem:
+	for_each_active_iommu(iommu, drhd)
+		kfree(iommu->iommu_state);
+
+	return -ENOMEM;
+}
+
+static void iommu_resume(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu = NULL;
+	unsigned long flag;
+
+	if (init_iommu_hw()) {
+		if (force_on)
+			panic("tboot: IOMMU setup failed, DMAR can not resume!\n");
+		else
+			WARN(1, "IOMMU setup failed, DMAR can not resume!\n");
+		return;
+	}
+
+	for_each_active_iommu(iommu, drhd) {
+
+		spin_lock_irqsave(&iommu->register_lock, flag);
+
+		writel(iommu->iommu_state[SR_DMAR_FECTL_REG],
+			iommu->reg + DMAR_FECTL_REG);
+		writel(iommu->iommu_state[SR_DMAR_FEDATA_REG],
+			iommu->reg + DMAR_FEDATA_REG);
+		writel(iommu->iommu_state[SR_DMAR_FEADDR_REG],
+			iommu->reg + DMAR_FEADDR_REG);
+		writel(iommu->iommu_state[SR_DMAR_FEUADDR_REG],
+			iommu->reg + DMAR_FEUADDR_REG);
+
+		spin_unlock_irqrestore(&iommu->register_lock, flag);
+	}
+
+	for_each_active_iommu(iommu, drhd)
+		kfree(iommu->iommu_state);
+}
+
+static struct syscore_ops iommu_syscore_ops = {
+	.resume		= iommu_resume,
+	.suspend	= iommu_suspend,
+};
+
+static void __init init_iommu_pm_ops(void)
+{
+	register_syscore_ops(&iommu_syscore_ops);
+}
+
+#else
+static inline void init_iommu_pm_ops(void) {}
+#endif	/* CONFIG_PM */
+
+/*
+ * Here we only respond to action of unbound device from driver.
+ *
+ * Added device is not attached to its DMAR domain here yet. That will happen
+ * when mapping the device to iova.
+ */
+static int device_notifier(struct notifier_block *nb,
+				  unsigned long action, void *data)
+{
+	struct device *dev = data;
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct dmar_domain *domain;
+
+	if (iommu_no_mapping(dev))
+		return 0;
+
+	domain = find_domain(pdev);
+	if (!domain)
+		return 0;
+
+	if (action == BUS_NOTIFY_UNBOUND_DRIVER && !iommu_pass_through) {
+		domain_remove_one_dev_info(domain, pdev);
+
+		if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
+		    !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) &&
+		    list_empty(&domain->devices))
+			domain_exit(domain);
+	}
+
+	return 0;
+}
+
+static struct notifier_block device_nb = {
+	.notifier_call = device_notifier,
+};
+
+int __init intel_iommu_init(void)
+{
+	int ret = 0;
+
+	/* VT-d is required for a TXT/tboot launch, so enforce that */
+	force_on = tboot_force_iommu();
+
+	if (dmar_table_init()) {
+		if (force_on)
+			panic("tboot: Failed to initialize DMAR table\n");
+		return 	-ENODEV;
+	}
+
+	if (dmar_dev_scope_init()) {
+		if (force_on)
+			panic("tboot: Failed to initialize DMAR device scope\n");
+		return 	-ENODEV;
+	}
+
+	/*
+	 * Check the need for DMA-remapping initialization now.
+	 * Above initialization will also be used by Interrupt-remapping.
+	 */
+	if (no_iommu || dmar_disabled)
+		return -ENODEV;
+
+	if (iommu_init_mempool()) {
+		if (force_on)
+			panic("tboot: Failed to initialize iommu memory\n");
+		return 	-ENODEV;
+	}
+
+	if (dmar_init_reserved_ranges()) {
+		if (force_on)
+			panic("tboot: Failed to reserve iommu ranges\n");
+		return 	-ENODEV;
+	}
+
+	init_no_remapping_devices();
+
+	ret = init_dmars();
+	if (ret) {
+		if (force_on)
+			panic("tboot: Failed to initialize DMARs\n");
+		printk(KERN_ERR "IOMMU: dmar init failed\n");
+		put_iova_domain(&reserved_iova_list);
+		iommu_exit_mempool();
+		return ret;
+	}
+	printk(KERN_INFO
+	"PCI-DMA: Intel(R) Virtualization Technology for Directed I/O\n");
+
+	init_timer(&unmap_timer);
+#ifdef CONFIG_SWIOTLB
+	swiotlb = 0;
+#endif
+	dma_ops = &intel_dma_ops;
+
+	init_iommu_pm_ops();
+
+	register_iommu(&intel_iommu_ops);
+
+	bus_register_notifier(&pci_bus_type, &device_nb);
+
+	return 0;
+}
+
+static void iommu_detach_dependent_devices(struct intel_iommu *iommu,
+					   struct pci_dev *pdev)
+{
+	struct pci_dev *tmp, *parent;
+
+	if (!iommu || !pdev)
+		return;
+
+	/* dependent device detach */
+	tmp = pci_find_upstream_pcie_bridge(pdev);
+	/* Secondary interface's bus number and devfn 0 */
+	if (tmp) {
+		parent = pdev->bus->self;
+		while (parent != tmp) {
+			iommu_detach_dev(iommu, parent->bus->number,
+					 parent->devfn);
+			parent = parent->bus->self;
+		}
+		if (pci_is_pcie(tmp)) /* this is a PCIe-to-PCI bridge */
+			iommu_detach_dev(iommu,
+				tmp->subordinate->number, 0);
+		else /* this is a legacy PCI bridge */
+			iommu_detach_dev(iommu, tmp->bus->number,
+					 tmp->devfn);
+	}
+}
+
+static void domain_remove_one_dev_info(struct dmar_domain *domain,
+					  struct pci_dev *pdev)
+{
+	struct device_domain_info *info;
+	struct intel_iommu *iommu;
+	unsigned long flags;
+	int found = 0;
+	struct list_head *entry, *tmp;
+
+	iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+				pdev->devfn);
+	if (!iommu)
+		return;
+
+	spin_lock_irqsave(&device_domain_lock, flags);
+	list_for_each_safe(entry, tmp, &domain->devices) {
+		info = list_entry(entry, struct device_domain_info, link);
+		if (info->segment == pci_domain_nr(pdev->bus) &&
+		    info->bus == pdev->bus->number &&
+		    info->devfn == pdev->devfn) {
+			list_del(&info->link);
+			list_del(&info->global);
+			if (info->dev)
+				info->dev->dev.archdata.iommu = NULL;
+			spin_unlock_irqrestore(&device_domain_lock, flags);
+
+			iommu_disable_dev_iotlb(info);
+			iommu_detach_dev(iommu, info->bus, info->devfn);
+			iommu_detach_dependent_devices(iommu, pdev);
+			free_devinfo_mem(info);
+
+			spin_lock_irqsave(&device_domain_lock, flags);
+
+			if (found)
+				break;
+			else
+				continue;
+		}
+
+		/* if there is no other devices under the same iommu
+		 * owned by this domain, clear this iommu in iommu_bmp
+		 * update iommu count and coherency
+		 */
+		if (iommu == device_to_iommu(info->segment, info->bus,
+					    info->devfn))
+			found = 1;
+	}
+
+	if (found == 0) {
+		unsigned long tmp_flags;
+		spin_lock_irqsave(&domain->iommu_lock, tmp_flags);
+		clear_bit(iommu->seq_id, &domain->iommu_bmp);
+		domain->iommu_count--;
+		domain_update_iommu_cap(domain);
+		spin_unlock_irqrestore(&domain->iommu_lock, tmp_flags);
+
+		if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
+		    !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)) {
+			spin_lock_irqsave(&iommu->lock, tmp_flags);
+			clear_bit(domain->id, iommu->domain_ids);
+			iommu->domains[domain->id] = NULL;
+			spin_unlock_irqrestore(&iommu->lock, tmp_flags);
+		}
+	}
+
+	spin_unlock_irqrestore(&device_domain_lock, flags);
+}
+
+static void vm_domain_remove_all_dev_info(struct dmar_domain *domain)
+{
+	struct device_domain_info *info;
+	struct intel_iommu *iommu;
+	unsigned long flags1, flags2;
+
+	spin_lock_irqsave(&device_domain_lock, flags1);
+	while (!list_empty(&domain->devices)) {
+		info = list_entry(domain->devices.next,
+			struct device_domain_info, link);
+		list_del(&info->link);
+		list_del(&info->global);
+		if (info->dev)
+			info->dev->dev.archdata.iommu = NULL;
+
+		spin_unlock_irqrestore(&device_domain_lock, flags1);
+
+		iommu_disable_dev_iotlb(info);
+		iommu = device_to_iommu(info->segment, info->bus, info->devfn);
+		iommu_detach_dev(iommu, info->bus, info->devfn);
+		iommu_detach_dependent_devices(iommu, info->dev);
+
+		/* clear this iommu in iommu_bmp, update iommu count
+		 * and capabilities
+		 */
+		spin_lock_irqsave(&domain->iommu_lock, flags2);
+		if (test_and_clear_bit(iommu->seq_id,
+				       &domain->iommu_bmp)) {
+			domain->iommu_count--;
+			domain_update_iommu_cap(domain);
+		}
+		spin_unlock_irqrestore(&domain->iommu_lock, flags2);
+
+		free_devinfo_mem(info);
+		spin_lock_irqsave(&device_domain_lock, flags1);
+	}
+	spin_unlock_irqrestore(&device_domain_lock, flags1);
+}
+
+/* domain id for virtual machine, it won't be set in context */
+static unsigned long vm_domid;
+
+static struct dmar_domain *iommu_alloc_vm_domain(void)
+{
+	struct dmar_domain *domain;
+
+	domain = alloc_domain_mem();
+	if (!domain)
+		return NULL;
+
+	domain->id = vm_domid++;
+	domain->nid = -1;
+	memset(&domain->iommu_bmp, 0, sizeof(unsigned long));
+	domain->flags = DOMAIN_FLAG_VIRTUAL_MACHINE;
+
+	return domain;
+}
+
+static int md_domain_init(struct dmar_domain *domain, int guest_width)
+{
+	int adjust_width;
+
+	init_iova_domain(&domain->iovad, DMA_32BIT_PFN);
+	spin_lock_init(&domain->iommu_lock);
+
+	domain_reserve_special_ranges(domain);
+
+	/* calculate AGAW */
+	domain->gaw = guest_width;
+	adjust_width = guestwidth_to_adjustwidth(guest_width);
+	domain->agaw = width_to_agaw(adjust_width);
+
+	INIT_LIST_HEAD(&domain->devices);
+
+	domain->iommu_count = 0;
+	domain->iommu_coherency = 0;
+	domain->iommu_snooping = 0;
+	domain->iommu_superpage = 0;
+	domain->max_addr = 0;
+	domain->nid = -1;
+
+	/* always allocate the top pgd */
+	domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid);
+	if (!domain->pgd)
+		return -ENOMEM;
+	domain_flush_cache(domain, domain->pgd, PAGE_SIZE);
+	return 0;
+}
+
+static void iommu_free_vm_domain(struct dmar_domain *domain)
+{
+	unsigned long flags;
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu;
+	unsigned long i;
+	unsigned long ndomains;
+
+	for_each_drhd_unit(drhd) {
+		if (drhd->ignored)
+			continue;
+		iommu = drhd->iommu;
+
+		ndomains = cap_ndoms(iommu->cap);
+		for_each_set_bit(i, iommu->domain_ids, ndomains) {
+			if (iommu->domains[i] == domain) {
+				spin_lock_irqsave(&iommu->lock, flags);
+				clear_bit(i, iommu->domain_ids);
+				iommu->domains[i] = NULL;
+				spin_unlock_irqrestore(&iommu->lock, flags);
+				break;
+			}
+		}
+	}
+}
+
+static void vm_domain_exit(struct dmar_domain *domain)
+{
+	/* Domain 0 is reserved, so dont process it */
+	if (!domain)
+		return;
+
+	vm_domain_remove_all_dev_info(domain);
+	/* destroy iovas */
+	put_iova_domain(&domain->iovad);
+
+	/* clear ptes */
+	dma_pte_clear_range(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+
+	/* free page tables */
+	dma_pte_free_pagetable(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+
+	iommu_free_vm_domain(domain);
+	free_domain_mem(domain);
+}
+
+static int intel_iommu_domain_init(struct iommu_domain *domain)
+{
+	struct dmar_domain *dmar_domain;
+
+	dmar_domain = iommu_alloc_vm_domain();
+	if (!dmar_domain) {
+		printk(KERN_ERR
+			"intel_iommu_domain_init: dmar_domain == NULL\n");
+		return -ENOMEM;
+	}
+	if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) {
+		printk(KERN_ERR
+			"intel_iommu_domain_init() failed\n");
+		vm_domain_exit(dmar_domain);
+		return -ENOMEM;
+	}
+	domain->priv = dmar_domain;
+
+	return 0;
+}
+
+static void intel_iommu_domain_destroy(struct iommu_domain *domain)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+
+	domain->priv = NULL;
+	vm_domain_exit(dmar_domain);
+}
+
+static int intel_iommu_attach_device(struct iommu_domain *domain,
+				     struct device *dev)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct intel_iommu *iommu;
+	int addr_width;
+
+	/* normally pdev is not mapped */
+	if (unlikely(domain_context_mapped(pdev))) {
+		struct dmar_domain *old_domain;
+
+		old_domain = find_domain(pdev);
+		if (old_domain) {
+			if (dmar_domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
+			    dmar_domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)
+				domain_remove_one_dev_info(old_domain, pdev);
+			else
+				domain_remove_dev_info(old_domain);
+		}
+	}
+
+	iommu = device_to_iommu(pci_domain_nr(pdev->bus), pdev->bus->number,
+				pdev->devfn);
+	if (!iommu)
+		return -ENODEV;
+
+	/* check if this iommu agaw is sufficient for max mapped address */
+	addr_width = agaw_to_width(iommu->agaw);
+	if (addr_width > cap_mgaw(iommu->cap))
+		addr_width = cap_mgaw(iommu->cap);
+
+	if (dmar_domain->max_addr > (1LL << addr_width)) {
+		printk(KERN_ERR "%s: iommu width (%d) is not "
+		       "sufficient for the mapped address (%llx)\n",
+		       __func__, addr_width, dmar_domain->max_addr);
+		return -EFAULT;
+	}
+	dmar_domain->gaw = addr_width;
+
+	/*
+	 * Knock out extra levels of page tables if necessary
+	 */
+	while (iommu->agaw < dmar_domain->agaw) {
+		struct dma_pte *pte;
+
+		pte = dmar_domain->pgd;
+		if (dma_pte_present(pte)) {
+			dmar_domain->pgd = (struct dma_pte *)
+				phys_to_virt(dma_pte_addr(pte));
+			free_pgtable_page(pte);
+		}
+		dmar_domain->agaw--;
+	}
+
+	return domain_add_dev_info(dmar_domain, pdev, CONTEXT_TT_MULTI_LEVEL);
+}
+
+static void intel_iommu_detach_device(struct iommu_domain *domain,
+				      struct device *dev)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	domain_remove_one_dev_info(dmar_domain, pdev);
+}
+
+static int intel_iommu_map(struct iommu_domain *domain,
+			   unsigned long iova, phys_addr_t hpa,
+			   int gfp_order, int iommu_prot)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+	u64 max_addr;
+	int prot = 0;
+	size_t size;
+	int ret;
+
+	if (iommu_prot & IOMMU_READ)
+		prot |= DMA_PTE_READ;
+	if (iommu_prot & IOMMU_WRITE)
+		prot |= DMA_PTE_WRITE;
+	if ((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping)
+		prot |= DMA_PTE_SNP;
+
+	size     = PAGE_SIZE << gfp_order;
+	max_addr = iova + size;
+	if (dmar_domain->max_addr < max_addr) {
+		u64 end;
+
+		/* check if minimum agaw is sufficient for mapped address */
+		end = __DOMAIN_MAX_ADDR(dmar_domain->gaw) + 1;
+		if (end < max_addr) {
+			printk(KERN_ERR "%s: iommu width (%d) is not "
+			       "sufficient for the mapped address (%llx)\n",
+			       __func__, dmar_domain->gaw, max_addr);
+			return -EFAULT;
+		}
+		dmar_domain->max_addr = max_addr;
+	}
+	/* Round up size to next multiple of PAGE_SIZE, if it and
+	   the low bits of hpa would take us onto the next page */
+	size = aligned_nrpages(hpa, size);
+	ret = domain_pfn_mapping(dmar_domain, iova >> VTD_PAGE_SHIFT,
+				 hpa >> VTD_PAGE_SHIFT, size, prot);
+	return ret;
+}
+
+static int intel_iommu_unmap(struct iommu_domain *domain,
+			     unsigned long iova, int gfp_order)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+	size_t size = PAGE_SIZE << gfp_order;
+
+	dma_pte_clear_range(dmar_domain, iova >> VTD_PAGE_SHIFT,
+			    (iova + size - 1) >> VTD_PAGE_SHIFT);
+
+	if (dmar_domain->max_addr == iova + size)
+		dmar_domain->max_addr = iova;
+
+	return gfp_order;
+}
+
+static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain,
+					    unsigned long iova)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+	struct dma_pte *pte;
+	u64 phys = 0;
+
+	pte = pfn_to_dma_pte(dmar_domain, iova >> VTD_PAGE_SHIFT, 0);
+	if (pte)
+		phys = dma_pte_addr(pte);
+
+	return phys;
+}
+
+static int intel_iommu_domain_has_cap(struct iommu_domain *domain,
+				      unsigned long cap)
+{
+	struct dmar_domain *dmar_domain = domain->priv;
+
+	if (cap == IOMMU_CAP_CACHE_COHERENCY)
+		return dmar_domain->iommu_snooping;
+	if (cap == IOMMU_CAP_INTR_REMAP)
+		return intr_remapping_enabled;
+
+	return 0;
+}
+
+static struct iommu_ops intel_iommu_ops = {
+	.domain_init	= intel_iommu_domain_init,
+	.domain_destroy = intel_iommu_domain_destroy,
+	.attach_dev	= intel_iommu_attach_device,
+	.detach_dev	= intel_iommu_detach_device,
+	.map		= intel_iommu_map,
+	.unmap		= intel_iommu_unmap,
+	.iova_to_phys	= intel_iommu_iova_to_phys,
+	.domain_has_cap = intel_iommu_domain_has_cap,
+};
+
+static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)
+{
+	/*
+	 * Mobile 4 Series Chipset neglects to set RWBF capability,
+	 * but needs it:
+	 */
+	printk(KERN_INFO "DMAR: Forcing write-buffer flush capability\n");
+	rwbf_quirk = 1;
+
+	/* https://bugzilla.redhat.com/show_bug.cgi?id=538163 */
+	if (dev->revision == 0x07) {
+		printk(KERN_INFO "DMAR: Disabling IOMMU for graphics on this chipset\n");
+		dmar_map_gfx = 0;
+	}
+}
+
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2a40, quirk_iommu_rwbf);
+
+#define GGC 0x52
+#define GGC_MEMORY_SIZE_MASK	(0xf << 8)
+#define GGC_MEMORY_SIZE_NONE	(0x0 << 8)
+#define GGC_MEMORY_SIZE_1M	(0x1 << 8)
+#define GGC_MEMORY_SIZE_2M	(0x3 << 8)
+#define GGC_MEMORY_VT_ENABLED	(0x8 << 8)
+#define GGC_MEMORY_SIZE_2M_VT	(0x9 << 8)
+#define GGC_MEMORY_SIZE_3M_VT	(0xa << 8)
+#define GGC_MEMORY_SIZE_4M_VT	(0xb << 8)
+
+static void __devinit quirk_calpella_no_shadow_gtt(struct pci_dev *dev)
+{
+	unsigned short ggc;
+
+	if (pci_read_config_word(dev, GGC, &ggc))
+		return;
+
+	if (!(ggc & GGC_MEMORY_VT_ENABLED)) {
+		printk(KERN_INFO "DMAR: BIOS has allocated no shadow GTT; disabling IOMMU for graphics\n");
+		dmar_map_gfx = 0;
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0040, quirk_calpella_no_shadow_gtt);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0044, quirk_calpella_no_shadow_gtt);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0062, quirk_calpella_no_shadow_gtt);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x006a, quirk_calpella_no_shadow_gtt);
+
+/* On Tylersburg chipsets, some BIOSes have been known to enable the
+   ISOCH DMAR unit for the Azalia sound device, but not give it any
+   TLB entries, which causes it to deadlock. Check for that.  We do
+   this in a function called from init_dmars(), instead of in a PCI
+   quirk, because we don't want to print the obnoxious "BIOS broken"
+   message if VT-d is actually disabled.
+*/
+static void __init check_tylersburg_isoch(void)
+{
+	struct pci_dev *pdev;
+	uint32_t vtisochctrl;
+
+	/* If there's no Azalia in the system anyway, forget it. */
+	pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x3a3e, NULL);
+	if (!pdev)
+		return;
+	pci_dev_put(pdev);
+
+	/* System Management Registers. Might be hidden, in which case
+	   we can't do the sanity check. But that's OK, because the
+	   known-broken BIOSes _don't_ actually hide it, so far. */
+	pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x342e, NULL);
+	if (!pdev)
+		return;
+
+	if (pci_read_config_dword(pdev, 0x188, &vtisochctrl)) {
+		pci_dev_put(pdev);
+		return;
+	}
+
+	pci_dev_put(pdev);
+
+	/* If Azalia DMA is routed to the non-isoch DMAR unit, fine. */
+	if (vtisochctrl & 1)
+		return;
+
+	/* Drop all bits other than the number of TLB entries */
+	vtisochctrl &= 0x1c;
+
+	/* If we have the recommended number of TLB entries (16), fine. */
+	if (vtisochctrl == 0x10)
+		return;
+
+	/* Zero TLB entries? You get to ride the short bus to school. */
+	if (!vtisochctrl) {
+		WARN(1, "Your BIOS is broken; DMA routed to ISOCH DMAR unit but no TLB space.\n"
+		     "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+		     dmi_get_system_info(DMI_BIOS_VENDOR),
+		     dmi_get_system_info(DMI_BIOS_VERSION),
+		     dmi_get_system_info(DMI_PRODUCT_VERSION));
+		iommu_identity_mapping |= IDENTMAP_AZALIA;
+		return;
+	}
+	
+	printk(KERN_WARNING "DMAR: Recommended TLB entries for ISOCH unit is 16; your BIOS set %d\n",
+	       vtisochctrl);
+}
diff --git a/drivers/iommu/intr_remapping.c b/drivers/iommu/intr_remapping.c
new file mode 100644
index 0000000..1a89d4a
--- /dev/null
+++ b/drivers/iommu/intr_remapping.c
@@ -0,0 +1,797 @@
+#include <linux/interrupt.h>
+#include <linux/dmar.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/hpet.h>
+#include <linux/pci.h>
+#include <linux/irq.h>
+#include <asm/io_apic.h>
+#include <asm/smp.h>
+#include <asm/cpu.h>
+#include <linux/intel-iommu.h>
+#include "intr_remapping.h"
+#include <acpi/acpi.h>
+#include <asm/pci-direct.h>
+
+static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
+static struct hpet_scope ir_hpet[MAX_HPET_TBS];
+static int ir_ioapic_num, ir_hpet_num;
+int intr_remapping_enabled;
+
+static int disable_intremap;
+static int disable_sourceid_checking;
+
+static __init int setup_nointremap(char *str)
+{
+	disable_intremap = 1;
+	return 0;
+}
+early_param("nointremap", setup_nointremap);
+
+static __init int setup_intremap(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!strncmp(str, "on", 2))
+		disable_intremap = 0;
+	else if (!strncmp(str, "off", 3))
+		disable_intremap = 1;
+	else if (!strncmp(str, "nosid", 5))
+		disable_sourceid_checking = 1;
+
+	return 0;
+}
+early_param("intremap", setup_intremap);
+
+static DEFINE_SPINLOCK(irq_2_ir_lock);
+
+static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
+{
+	struct irq_cfg *cfg = irq_get_chip_data(irq);
+	return cfg ? &cfg->irq_2_iommu : NULL;
+}
+
+int get_irte(int irq, struct irte *entry)
+{
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	unsigned long flags;
+	int index;
+
+	if (!entry || !irq_iommu)
+		return -1;
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
+	*entry = *(irq_iommu->iommu->ir_table->base + index);
+
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+	return 0;
+}
+
+int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
+{
+	struct ir_table *table = iommu->ir_table;
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	u16 index, start_index;
+	unsigned int mask = 0;
+	unsigned long flags;
+	int i;
+
+	if (!count || !irq_iommu)
+		return -1;
+
+	/*
+	 * start the IRTE search from index 0.
+	 */
+	index = start_index = 0;
+
+	if (count > 1) {
+		count = __roundup_pow_of_two(count);
+		mask = ilog2(count);
+	}
+
+	if (mask > ecap_max_handle_mask(iommu->ecap)) {
+		printk(KERN_ERR
+		       "Requested mask %x exceeds the max invalidation handle"
+		       " mask value %Lx\n", mask,
+		       ecap_max_handle_mask(iommu->ecap));
+		return -1;
+	}
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+	do {
+		for (i = index; i < index + count; i++)
+			if  (table->base[i].present)
+				break;
+		/* empty index found */
+		if (i == index + count)
+			break;
+
+		index = (index + count) % INTR_REMAP_TABLE_ENTRIES;
+
+		if (index == start_index) {
+			spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+			printk(KERN_ERR "can't allocate an IRTE\n");
+			return -1;
+		}
+	} while (1);
+
+	for (i = index; i < index + count; i++)
+		table->base[i].present = 1;
+
+	irq_iommu->iommu = iommu;
+	irq_iommu->irte_index =  index;
+	irq_iommu->sub_handle = 0;
+	irq_iommu->irte_mask = mask;
+
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+	return index;
+}
+
+static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
+{
+	struct qi_desc desc;
+
+	desc.low = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
+		   | QI_IEC_SELECTIVE;
+	desc.high = 0;
+
+	return qi_submit_sync(&desc, iommu);
+}
+
+int map_irq_to_irte_handle(int irq, u16 *sub_handle)
+{
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	unsigned long flags;
+	int index;
+
+	if (!irq_iommu)
+		return -1;
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+	*sub_handle = irq_iommu->sub_handle;
+	index = irq_iommu->irte_index;
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+	return index;
+}
+
+int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
+{
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	unsigned long flags;
+
+	if (!irq_iommu)
+		return -1;
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+	irq_iommu->iommu = iommu;
+	irq_iommu->irte_index = index;
+	irq_iommu->sub_handle = subhandle;
+	irq_iommu->irte_mask = 0;
+
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+	return 0;
+}
+
+int modify_irte(int irq, struct irte *irte_modified)
+{
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	struct intel_iommu *iommu;
+	unsigned long flags;
+	struct irte *irte;
+	int rc, index;
+
+	if (!irq_iommu)
+		return -1;
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+	iommu = irq_iommu->iommu;
+
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
+	irte = &iommu->ir_table->base[index];
+
+	set_64bit(&irte->low, irte_modified->low);
+	set_64bit(&irte->high, irte_modified->high);
+	__iommu_flush_cache(iommu, irte, sizeof(*irte));
+
+	rc = qi_flush_iec(iommu, index, 0);
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+	return rc;
+}
+
+struct intel_iommu *map_hpet_to_ir(u8 hpet_id)
+{
+	int i;
+
+	for (i = 0; i < MAX_HPET_TBS; i++)
+		if (ir_hpet[i].id == hpet_id)
+			return ir_hpet[i].iommu;
+	return NULL;
+}
+
+struct intel_iommu *map_ioapic_to_ir(int apic)
+{
+	int i;
+
+	for (i = 0; i < MAX_IO_APICS; i++)
+		if (ir_ioapic[i].id == apic)
+			return ir_ioapic[i].iommu;
+	return NULL;
+}
+
+struct intel_iommu *map_dev_to_ir(struct pci_dev *dev)
+{
+	struct dmar_drhd_unit *drhd;
+
+	drhd = dmar_find_matched_drhd_unit(dev);
+	if (!drhd)
+		return NULL;
+
+	return drhd->iommu;
+}
+
+static int clear_entries(struct irq_2_iommu *irq_iommu)
+{
+	struct irte *start, *entry, *end;
+	struct intel_iommu *iommu;
+	int index;
+
+	if (irq_iommu->sub_handle)
+		return 0;
+
+	iommu = irq_iommu->iommu;
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
+
+	start = iommu->ir_table->base + index;
+	end = start + (1 << irq_iommu->irte_mask);
+
+	for (entry = start; entry < end; entry++) {
+		set_64bit(&entry->low, 0);
+		set_64bit(&entry->high, 0);
+	}
+
+	return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
+}
+
+int free_irte(int irq)
+{
+	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	unsigned long flags;
+	int rc;
+
+	if (!irq_iommu)
+		return -1;
+
+	spin_lock_irqsave(&irq_2_ir_lock, flags);
+
+	rc = clear_entries(irq_iommu);
+
+	irq_iommu->iommu = NULL;
+	irq_iommu->irte_index = 0;
+	irq_iommu->sub_handle = 0;
+	irq_iommu->irte_mask = 0;
+
+	spin_unlock_irqrestore(&irq_2_ir_lock, flags);
+
+	return rc;
+}
+
+/*
+ * source validation type
+ */
+#define SVT_NO_VERIFY		0x0  /* no verification is required */
+#define SVT_VERIFY_SID_SQ	0x1  /* verify using SID and SQ fields */
+#define SVT_VERIFY_BUS		0x2  /* verify bus of request-id */
+
+/*
+ * source-id qualifier
+ */
+#define SQ_ALL_16	0x0  /* verify all 16 bits of request-id */
+#define SQ_13_IGNORE_1	0x1  /* verify most significant 13 bits, ignore
+			      * the third least significant bit
+			      */
+#define SQ_13_IGNORE_2	0x2  /* verify most significant 13 bits, ignore
+			      * the second and third least significant bits
+			      */
+#define SQ_13_IGNORE_3	0x3  /* verify most significant 13 bits, ignore
+			      * the least three significant bits
+			      */
+
+/*
+ * set SVT, SQ and SID fields of irte to verify
+ * source ids of interrupt requests
+ */
+static void set_irte_sid(struct irte *irte, unsigned int svt,
+			 unsigned int sq, unsigned int sid)
+{
+	if (disable_sourceid_checking)
+		svt = SVT_NO_VERIFY;
+	irte->svt = svt;
+	irte->sq = sq;
+	irte->sid = sid;
+}
+
+int set_ioapic_sid(struct irte *irte, int apic)
+{
+	int i;
+	u16 sid = 0;
+
+	if (!irte)
+		return -1;
+
+	for (i = 0; i < MAX_IO_APICS; i++) {
+		if (ir_ioapic[i].id == apic) {
+			sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
+			break;
+		}
+	}
+
+	if (sid == 0) {
+		pr_warning("Failed to set source-id of IOAPIC (%d)\n", apic);
+		return -1;
+	}
+
+	set_irte_sid(irte, 1, 0, sid);
+
+	return 0;
+}
+
+int set_hpet_sid(struct irte *irte, u8 id)
+{
+	int i;
+	u16 sid = 0;
+
+	if (!irte)
+		return -1;
+
+	for (i = 0; i < MAX_HPET_TBS; i++) {
+		if (ir_hpet[i].id == id) {
+			sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
+			break;
+		}
+	}
+
+	if (sid == 0) {
+		pr_warning("Failed to set source-id of HPET block (%d)\n", id);
+		return -1;
+	}
+
+	/*
+	 * Should really use SQ_ALL_16. Some platforms are broken.
+	 * While we figure out the right quirks for these broken platforms, use
+	 * SQ_13_IGNORE_3 for now.
+	 */
+	set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_13_IGNORE_3, sid);
+
+	return 0;
+}
+
+int set_msi_sid(struct irte *irte, struct pci_dev *dev)
+{
+	struct pci_dev *bridge;
+
+	if (!irte || !dev)
+		return -1;
+
+	/* PCIe device or Root Complex integrated PCI device */
+	if (pci_is_pcie(dev) || !dev->bus->parent) {
+		set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
+			     (dev->bus->number << 8) | dev->devfn);
+		return 0;
+	}
+
+	bridge = pci_find_upstream_pcie_bridge(dev);
+	if (bridge) {
+		if (pci_is_pcie(bridge))/* this is a PCIe-to-PCI/PCIX bridge */
+			set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
+				(bridge->bus->number << 8) | dev->bus->number);
+		else /* this is a legacy PCI bridge */
+			set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
+				(bridge->bus->number << 8) | bridge->devfn);
+	}
+
+	return 0;
+}
+
+static void iommu_set_intr_remapping(struct intel_iommu *iommu, int mode)
+{
+	u64 addr;
+	u32 sts;
+	unsigned long flags;
+
+	addr = virt_to_phys((void *)iommu->ir_table->base);
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+
+	dmar_writeq(iommu->reg + DMAR_IRTA_REG,
+		    (addr) | IR_X2APIC_MODE(mode) | INTR_REMAP_TABLE_REG_SIZE);
+
+	/* Set interrupt-remapping table pointer */
+	iommu->gcmd |= DMA_GCMD_SIRTP;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (sts & DMA_GSTS_IRTPS), sts);
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+
+	/*
+	 * global invalidation of interrupt entry cache before enabling
+	 * interrupt-remapping.
+	 */
+	qi_global_iec(iommu);
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+
+	/* Enable interrupt-remapping */
+	iommu->gcmd |= DMA_GCMD_IRE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, (sts & DMA_GSTS_IRES), sts);
+
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+
+static int setup_intr_remapping(struct intel_iommu *iommu, int mode)
+{
+	struct ir_table *ir_table;
+	struct page *pages;
+
+	ir_table = iommu->ir_table = kzalloc(sizeof(struct ir_table),
+					     GFP_ATOMIC);
+
+	if (!iommu->ir_table)
+		return -ENOMEM;
+
+	pages = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
+				 INTR_REMAP_PAGE_ORDER);
+
+	if (!pages) {
+		printk(KERN_ERR "failed to allocate pages of order %d\n",
+		       INTR_REMAP_PAGE_ORDER);
+		kfree(iommu->ir_table);
+		return -ENOMEM;
+	}
+
+	ir_table->base = page_address(pages);
+
+	iommu_set_intr_remapping(iommu, mode);
+	return 0;
+}
+
+/*
+ * Disable Interrupt Remapping.
+ */
+static void iommu_disable_intr_remapping(struct intel_iommu *iommu)
+{
+	unsigned long flags;
+	u32 sts;
+
+	if (!ecap_ir_support(iommu->ecap))
+		return;
+
+	/*
+	 * global invalidation of interrupt entry cache before disabling
+	 * interrupt-remapping.
+	 */
+	qi_global_iec(iommu);
+
+	spin_lock_irqsave(&iommu->register_lock, flags);
+
+	sts = dmar_readq(iommu->reg + DMAR_GSTS_REG);
+	if (!(sts & DMA_GSTS_IRES))
+		goto end;
+
+	iommu->gcmd &= ~DMA_GCMD_IRE;
+	writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
+
+	IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG,
+		      readl, !(sts & DMA_GSTS_IRES), sts);
+
+end:
+	spin_unlock_irqrestore(&iommu->register_lock, flags);
+}
+
+int __init intr_remapping_supported(void)
+{
+	struct dmar_drhd_unit *drhd;
+
+	if (disable_intremap)
+		return 0;
+
+	if (!dmar_ir_support())
+		return 0;
+
+	for_each_drhd_unit(drhd) {
+		struct intel_iommu *iommu = drhd->iommu;
+
+		if (!ecap_ir_support(iommu->ecap))
+			return 0;
+	}
+
+	return 1;
+}
+
+int __init enable_intr_remapping(int eim)
+{
+	struct dmar_drhd_unit *drhd;
+	int setup = 0;
+
+	if (parse_ioapics_under_ir() != 1) {
+		printk(KERN_INFO "Not enable interrupt remapping\n");
+		return -1;
+	}
+
+	for_each_drhd_unit(drhd) {
+		struct intel_iommu *iommu = drhd->iommu;
+
+		/*
+		 * If the queued invalidation is already initialized,
+		 * shouldn't disable it.
+		 */
+		if (iommu->qi)
+			continue;
+
+		/*
+		 * Clear previous faults.
+		 */
+		dmar_fault(-1, iommu);
+
+		/*
+		 * Disable intr remapping and queued invalidation, if already
+		 * enabled prior to OS handover.
+		 */
+		iommu_disable_intr_remapping(iommu);
+
+		dmar_disable_qi(iommu);
+	}
+
+	/*
+	 * check for the Interrupt-remapping support
+	 */
+	for_each_drhd_unit(drhd) {
+		struct intel_iommu *iommu = drhd->iommu;
+
+		if (!ecap_ir_support(iommu->ecap))
+			continue;
+
+		if (eim && !ecap_eim_support(iommu->ecap)) {
+			printk(KERN_INFO "DRHD %Lx: EIM not supported by DRHD, "
+			       " ecap %Lx\n", drhd->reg_base_addr, iommu->ecap);
+			return -1;
+		}
+	}
+
+	/*
+	 * Enable queued invalidation for all the DRHD's.
+	 */
+	for_each_drhd_unit(drhd) {
+		int ret;
+		struct intel_iommu *iommu = drhd->iommu;
+		ret = dmar_enable_qi(iommu);
+
+		if (ret) {
+			printk(KERN_ERR "DRHD %Lx: failed to enable queued, "
+			       " invalidation, ecap %Lx, ret %d\n",
+			       drhd->reg_base_addr, iommu->ecap, ret);
+			return -1;
+		}
+	}
+
+	/*
+	 * Setup Interrupt-remapping for all the DRHD's now.
+	 */
+	for_each_drhd_unit(drhd) {
+		struct intel_iommu *iommu = drhd->iommu;
+
+		if (!ecap_ir_support(iommu->ecap))
+			continue;
+
+		if (setup_intr_remapping(iommu, eim))
+			goto error;
+
+		setup = 1;
+	}
+
+	if (!setup)
+		goto error;
+
+	intr_remapping_enabled = 1;
+
+	return 0;
+
+error:
+	/*
+	 * handle error condition gracefully here!
+	 */
+	return -1;
+}
+
+static void ir_parse_one_hpet_scope(struct acpi_dmar_device_scope *scope,
+				      struct intel_iommu *iommu)
+{
+	struct acpi_dmar_pci_path *path;
+	u8 bus;
+	int count;
+
+	bus = scope->bus;
+	path = (struct acpi_dmar_pci_path *)(scope + 1);
+	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
+		/ sizeof(struct acpi_dmar_pci_path);
+
+	while (--count > 0) {
+		/*
+		 * Access PCI directly due to the PCI
+		 * subsystem isn't initialized yet.
+		 */
+		bus = read_pci_config_byte(bus, path->dev, path->fn,
+					   PCI_SECONDARY_BUS);
+		path++;
+	}
+	ir_hpet[ir_hpet_num].bus   = bus;
+	ir_hpet[ir_hpet_num].devfn = PCI_DEVFN(path->dev, path->fn);
+	ir_hpet[ir_hpet_num].iommu = iommu;
+	ir_hpet[ir_hpet_num].id    = scope->enumeration_id;
+	ir_hpet_num++;
+}
+
+static void ir_parse_one_ioapic_scope(struct acpi_dmar_device_scope *scope,
+				      struct intel_iommu *iommu)
+{
+	struct acpi_dmar_pci_path *path;
+	u8 bus;
+	int count;
+
+	bus = scope->bus;
+	path = (struct acpi_dmar_pci_path *)(scope + 1);
+	count = (scope->length - sizeof(struct acpi_dmar_device_scope))
+		/ sizeof(struct acpi_dmar_pci_path);
+
+	while (--count > 0) {
+		/*
+		 * Access PCI directly due to the PCI
+		 * subsystem isn't initialized yet.
+		 */
+		bus = read_pci_config_byte(bus, path->dev, path->fn,
+					   PCI_SECONDARY_BUS);
+		path++;
+	}
+
+	ir_ioapic[ir_ioapic_num].bus   = bus;
+	ir_ioapic[ir_ioapic_num].devfn = PCI_DEVFN(path->dev, path->fn);
+	ir_ioapic[ir_ioapic_num].iommu = iommu;
+	ir_ioapic[ir_ioapic_num].id    = scope->enumeration_id;
+	ir_ioapic_num++;
+}
+
+static int ir_parse_ioapic_hpet_scope(struct acpi_dmar_header *header,
+				      struct intel_iommu *iommu)
+{
+	struct acpi_dmar_hardware_unit *drhd;
+	struct acpi_dmar_device_scope *scope;
+	void *start, *end;
+
+	drhd = (struct acpi_dmar_hardware_unit *)header;
+
+	start = (void *)(drhd + 1);
+	end = ((void *)drhd) + header->length;
+
+	while (start < end) {
+		scope = start;
+		if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_IOAPIC) {
+			if (ir_ioapic_num == MAX_IO_APICS) {
+				printk(KERN_WARNING "Exceeded Max IO APICS\n");
+				return -1;
+			}
+
+			printk(KERN_INFO "IOAPIC id %d under DRHD base "
+			       " 0x%Lx IOMMU %d\n", scope->enumeration_id,
+			       drhd->address, iommu->seq_id);
+
+			ir_parse_one_ioapic_scope(scope, iommu);
+		} else if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_HPET) {
+			if (ir_hpet_num == MAX_HPET_TBS) {
+				printk(KERN_WARNING "Exceeded Max HPET blocks\n");
+				return -1;
+			}
+
+			printk(KERN_INFO "HPET id %d under DRHD base"
+			       " 0x%Lx\n", scope->enumeration_id,
+			       drhd->address);
+
+			ir_parse_one_hpet_scope(scope, iommu);
+		}
+		start += scope->length;
+	}
+
+	return 0;
+}
+
+/*
+ * Finds the assocaition between IOAPIC's and its Interrupt-remapping
+ * hardware unit.
+ */
+int __init parse_ioapics_under_ir(void)
+{
+	struct dmar_drhd_unit *drhd;
+	int ir_supported = 0;
+
+	for_each_drhd_unit(drhd) {
+		struct intel_iommu *iommu = drhd->iommu;
+
+		if (ecap_ir_support(iommu->ecap)) {
+			if (ir_parse_ioapic_hpet_scope(drhd->hdr, iommu))
+				return -1;
+
+			ir_supported = 1;
+		}
+	}
+
+	if (ir_supported && ir_ioapic_num != nr_ioapics) {
+		printk(KERN_WARNING
+		       "Not all IO-APIC's listed under remapping hardware\n");
+		return -1;
+	}
+
+	return ir_supported;
+}
+
+void disable_intr_remapping(void)
+{
+	struct dmar_drhd_unit *drhd;
+	struct intel_iommu *iommu = NULL;
+
+	/*
+	 * Disable Interrupt-remapping for all the DRHD's now.
+	 */
+	for_each_iommu(iommu, drhd) {
+		if (!ecap_ir_support(iommu->ecap))
+			continue;
+
+		iommu_disable_intr_remapping(iommu);
+	}
+}
+
+int reenable_intr_remapping(int eim)
+{
+	struct dmar_drhd_unit *drhd;
+	int setup = 0;
+	struct intel_iommu *iommu = NULL;
+
+	for_each_iommu(iommu, drhd)
+		if (iommu->qi)
+			dmar_reenable_qi(iommu);
+
+	/*
+	 * Setup Interrupt-remapping for all the DRHD's now.
+	 */
+	for_each_iommu(iommu, drhd) {
+		if (!ecap_ir_support(iommu->ecap))
+			continue;
+
+		/* Set up interrupt remapping for iommu.*/
+		iommu_set_intr_remapping(iommu, eim);
+		setup = 1;
+	}
+
+	if (!setup)
+		goto error;
+
+	return 0;
+
+error:
+	/*
+	 * handle error condition gracefully here!
+	 */
+	return -1;
+}
+
diff --git a/drivers/iommu/intr_remapping.h b/drivers/iommu/intr_remapping.h
new file mode 100644
index 0000000..5662fec
--- /dev/null
+++ b/drivers/iommu/intr_remapping.h
@@ -0,0 +1,17 @@
+#include <linux/intel-iommu.h>
+
+struct ioapic_scope {
+	struct intel_iommu *iommu;
+	unsigned int id;
+	unsigned int bus;	/* PCI bus number */
+	unsigned int devfn;	/* PCI devfn number */
+};
+
+struct hpet_scope {
+	struct intel_iommu *iommu;
+	u8 id;
+	unsigned int bus;
+	unsigned int devfn;
+};
+
+#define IR_X2APIC_MODE(mode) (mode ? (1 << 11) : 0)
diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
new file mode 100644
index 0000000..c5c274a
--- /dev/null
+++ b/drivers/iommu/iova.c
@@ -0,0 +1,435 @@
+/*
+ * Copyright © 2006-2009, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ */
+
+#include <linux/iova.h>
+
+void
+init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit)
+{
+	spin_lock_init(&iovad->iova_rbtree_lock);
+	iovad->rbroot = RB_ROOT;
+	iovad->cached32_node = NULL;
+	iovad->dma_32bit_pfn = pfn_32bit;
+}
+
+static struct rb_node *
+__get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn)
+{
+	if ((*limit_pfn != iovad->dma_32bit_pfn) ||
+		(iovad->cached32_node == NULL))
+		return rb_last(&iovad->rbroot);
+	else {
+		struct rb_node *prev_node = rb_prev(iovad->cached32_node);
+		struct iova *curr_iova =
+			container_of(iovad->cached32_node, struct iova, node);
+		*limit_pfn = curr_iova->pfn_lo - 1;
+		return prev_node;
+	}
+}
+
+static void
+__cached_rbnode_insert_update(struct iova_domain *iovad,
+	unsigned long limit_pfn, struct iova *new)
+{
+	if (limit_pfn != iovad->dma_32bit_pfn)
+		return;
+	iovad->cached32_node = &new->node;
+}
+
+static void
+__cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
+{
+	struct iova *cached_iova;
+	struct rb_node *curr;
+
+	if (!iovad->cached32_node)
+		return;
+	curr = iovad->cached32_node;
+	cached_iova = container_of(curr, struct iova, node);
+
+	if (free->pfn_lo >= cached_iova->pfn_lo) {
+		struct rb_node *node = rb_next(&free->node);
+		struct iova *iova = container_of(node, struct iova, node);
+
+		/* only cache if it's below 32bit pfn */
+		if (node && iova->pfn_lo < iovad->dma_32bit_pfn)
+			iovad->cached32_node = node;
+		else
+			iovad->cached32_node = NULL;
+	}
+}
+
+/* Computes the padding size required, to make the
+ * the start address naturally aligned on its size
+ */
+static int
+iova_get_pad_size(int size, unsigned int limit_pfn)
+{
+	unsigned int pad_size = 0;
+	unsigned int order = ilog2(size);
+
+	if (order)
+		pad_size = (limit_pfn + 1) % (1 << order);
+
+	return pad_size;
+}
+
+static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
+		unsigned long size, unsigned long limit_pfn,
+			struct iova *new, bool size_aligned)
+{
+	struct rb_node *prev, *curr = NULL;
+	unsigned long flags;
+	unsigned long saved_pfn;
+	unsigned int pad_size = 0;
+
+	/* Walk the tree backwards */
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	saved_pfn = limit_pfn;
+	curr = __get_cached_rbnode(iovad, &limit_pfn);
+	prev = curr;
+	while (curr) {
+		struct iova *curr_iova = container_of(curr, struct iova, node);
+
+		if (limit_pfn < curr_iova->pfn_lo)
+			goto move_left;
+		else if (limit_pfn < curr_iova->pfn_hi)
+			goto adjust_limit_pfn;
+		else {
+			if (size_aligned)
+				pad_size = iova_get_pad_size(size, limit_pfn);
+			if ((curr_iova->pfn_hi + size + pad_size) <= limit_pfn)
+				break;	/* found a free slot */
+		}
+adjust_limit_pfn:
+		limit_pfn = curr_iova->pfn_lo - 1;
+move_left:
+		prev = curr;
+		curr = rb_prev(curr);
+	}
+
+	if (!curr) {
+		if (size_aligned)
+			pad_size = iova_get_pad_size(size, limit_pfn);
+		if ((IOVA_START_PFN + size + pad_size) > limit_pfn) {
+			spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+			return -ENOMEM;
+		}
+	}
+
+	/* pfn_lo will point to size aligned address if size_aligned is set */
+	new->pfn_lo = limit_pfn - (size + pad_size) + 1;
+	new->pfn_hi = new->pfn_lo + size - 1;
+
+	/* Insert the new_iova into domain rbtree by holding writer lock */
+	/* Add new node and rebalance tree. */
+	{
+		struct rb_node **entry, *parent = NULL;
+
+		/* If we have 'prev', it's a valid place to start the
+		   insertion. Otherwise, start from the root. */
+		if (prev)
+			entry = &prev;
+		else
+			entry = &iovad->rbroot.rb_node;
+
+		/* Figure out where to put new node */
+		while (*entry) {
+			struct iova *this = container_of(*entry,
+							struct iova, node);
+			parent = *entry;
+
+			if (new->pfn_lo < this->pfn_lo)
+				entry = &((*entry)->rb_left);
+			else if (new->pfn_lo > this->pfn_lo)
+				entry = &((*entry)->rb_right);
+			else
+				BUG(); /* this should not happen */
+		}
+
+		/* Add new node and rebalance tree. */
+		rb_link_node(&new->node, parent, entry);
+		rb_insert_color(&new->node, &iovad->rbroot);
+	}
+	__cached_rbnode_insert_update(iovad, saved_pfn, new);
+
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+
+
+	return 0;
+}
+
+static void
+iova_insert_rbtree(struct rb_root *root, struct iova *iova)
+{
+	struct rb_node **new = &(root->rb_node), *parent = NULL;
+	/* Figure out where to put new node */
+	while (*new) {
+		struct iova *this = container_of(*new, struct iova, node);
+		parent = *new;
+
+		if (iova->pfn_lo < this->pfn_lo)
+			new = &((*new)->rb_left);
+		else if (iova->pfn_lo > this->pfn_lo)
+			new = &((*new)->rb_right);
+		else
+			BUG(); /* this should not happen */
+	}
+	/* Add new node and rebalance tree. */
+	rb_link_node(&iova->node, parent, new);
+	rb_insert_color(&iova->node, root);
+}
+
+/**
+ * alloc_iova - allocates an iova
+ * @iovad - iova domain in question
+ * @size - size of page frames to allocate
+ * @limit_pfn - max limit address
+ * @size_aligned - set if size_aligned address range is required
+ * This function allocates an iova in the range limit_pfn to IOVA_START_PFN
+ * looking from limit_pfn instead from IOVA_START_PFN. If the size_aligned
+ * flag is set then the allocated address iova->pfn_lo will be naturally
+ * aligned on roundup_power_of_two(size).
+ */
+struct iova *
+alloc_iova(struct iova_domain *iovad, unsigned long size,
+	unsigned long limit_pfn,
+	bool size_aligned)
+{
+	struct iova *new_iova;
+	int ret;
+
+	new_iova = alloc_iova_mem();
+	if (!new_iova)
+		return NULL;
+
+	/* If size aligned is set then round the size to
+	 * to next power of two.
+	 */
+	if (size_aligned)
+		size = __roundup_pow_of_two(size);
+
+	ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn,
+			new_iova, size_aligned);
+
+	if (ret) {
+		free_iova_mem(new_iova);
+		return NULL;
+	}
+
+	return new_iova;
+}
+
+/**
+ * find_iova - find's an iova for a given pfn
+ * @iovad - iova domain in question.
+ * pfn - page frame number
+ * This function finds and returns an iova belonging to the
+ * given doamin which matches the given pfn.
+ */
+struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
+{
+	unsigned long flags;
+	struct rb_node *node;
+
+	/* Take the lock so that no other thread is manipulating the rbtree */
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	node = iovad->rbroot.rb_node;
+	while (node) {
+		struct iova *iova = container_of(node, struct iova, node);
+
+		/* If pfn falls within iova's range, return iova */
+		if ((pfn >= iova->pfn_lo) && (pfn <= iova->pfn_hi)) {
+			spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+			/* We are not holding the lock while this iova
+			 * is referenced by the caller as the same thread
+			 * which called this function also calls __free_iova()
+			 * and it is by desing that only one thread can possibly
+			 * reference a particular iova and hence no conflict.
+			 */
+			return iova;
+		}
+
+		if (pfn < iova->pfn_lo)
+			node = node->rb_left;
+		else if (pfn > iova->pfn_lo)
+			node = node->rb_right;
+	}
+
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+	return NULL;
+}
+
+/**
+ * __free_iova - frees the given iova
+ * @iovad: iova domain in question.
+ * @iova: iova in question.
+ * Frees the given iova belonging to the giving domain
+ */
+void
+__free_iova(struct iova_domain *iovad, struct iova *iova)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	__cached_rbnode_delete_update(iovad, iova);
+	rb_erase(&iova->node, &iovad->rbroot);
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+	free_iova_mem(iova);
+}
+
+/**
+ * free_iova - finds and frees the iova for a given pfn
+ * @iovad: - iova domain in question.
+ * @pfn: - pfn that is allocated previously
+ * This functions finds an iova for a given pfn and then
+ * frees the iova from that domain.
+ */
+void
+free_iova(struct iova_domain *iovad, unsigned long pfn)
+{
+	struct iova *iova = find_iova(iovad, pfn);
+	if (iova)
+		__free_iova(iovad, iova);
+
+}
+
+/**
+ * put_iova_domain - destroys the iova doamin
+ * @iovad: - iova domain in question.
+ * All the iova's in that domain are destroyed.
+ */
+void put_iova_domain(struct iova_domain *iovad)
+{
+	struct rb_node *node;
+	unsigned long flags;
+
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	node = rb_first(&iovad->rbroot);
+	while (node) {
+		struct iova *iova = container_of(node, struct iova, node);
+		rb_erase(node, &iovad->rbroot);
+		free_iova_mem(iova);
+		node = rb_first(&iovad->rbroot);
+	}
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+}
+
+static int
+__is_range_overlap(struct rb_node *node,
+	unsigned long pfn_lo, unsigned long pfn_hi)
+{
+	struct iova *iova = container_of(node, struct iova, node);
+
+	if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo))
+		return 1;
+	return 0;
+}
+
+static struct iova *
+__insert_new_range(struct iova_domain *iovad,
+	unsigned long pfn_lo, unsigned long pfn_hi)
+{
+	struct iova *iova;
+
+	iova = alloc_iova_mem();
+	if (!iova)
+		return iova;
+
+	iova->pfn_hi = pfn_hi;
+	iova->pfn_lo = pfn_lo;
+	iova_insert_rbtree(&iovad->rbroot, iova);
+	return iova;
+}
+
+static void
+__adjust_overlap_range(struct iova *iova,
+	unsigned long *pfn_lo, unsigned long *pfn_hi)
+{
+	if (*pfn_lo < iova->pfn_lo)
+		iova->pfn_lo = *pfn_lo;
+	if (*pfn_hi > iova->pfn_hi)
+		*pfn_lo = iova->pfn_hi + 1;
+}
+
+/**
+ * reserve_iova - reserves an iova in the given range
+ * @iovad: - iova domain pointer
+ * @pfn_lo: - lower page frame address
+ * @pfn_hi:- higher pfn adderss
+ * This function allocates reserves the address range from pfn_lo to pfn_hi so
+ * that this address is not dished out as part of alloc_iova.
+ */
+struct iova *
+reserve_iova(struct iova_domain *iovad,
+	unsigned long pfn_lo, unsigned long pfn_hi)
+{
+	struct rb_node *node;
+	unsigned long flags;
+	struct iova *iova;
+	unsigned int overlap = 0;
+
+	spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+	for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
+		if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
+			iova = container_of(node, struct iova, node);
+			__adjust_overlap_range(iova, &pfn_lo, &pfn_hi);
+			if ((pfn_lo >= iova->pfn_lo) &&
+				(pfn_hi <= iova->pfn_hi))
+				goto finish;
+			overlap = 1;
+
+		} else if (overlap)
+				break;
+	}
+
+	/* We are here either because this is the first reserver node
+	 * or need to insert remaining non overlap addr range
+	 */
+	iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
+finish:
+
+	spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+	return iova;
+}
+
+/**
+ * copy_reserved_iova - copies the reserved between domains
+ * @from: - source doamin from where to copy
+ * @to: - destination domin where to copy
+ * This function copies reserved iova's from one doamin to
+ * other.
+ */
+void
+copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
+{
+	unsigned long flags;
+	struct rb_node *node;
+
+	spin_lock_irqsave(&from->iova_rbtree_lock, flags);
+	for (node = rb_first(&from->rbroot); node; node = rb_next(node)) {
+		struct iova *iova = container_of(node, struct iova, node);
+		struct iova *new_iova;
+		new_iova = reserve_iova(to, iova->pfn_lo, iova->pfn_hi);
+		if (!new_iova)
+			printk(KERN_ERR "Reserve iova range %lx@%lx failed\n",
+				iova->pfn_lo, iova->pfn_lo);
+	}
+	spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
+}