x86: amd_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.

Compile-tested on x86_64.

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

3 files changed, 1 insertions, 2793 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 460d5737001..1b6a2e212db 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -680,34 +680,6 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 	  If unsure, say Y.
 
-config AMD_IOMMU
-	bool "AMD IOMMU support"
-	select SWIOTLB
-	select PCI_MSI
-	select PCI_IOV
-	select IOMMU_API
-	depends on X86_64 && PCI && ACPI
-	---help---
-	  With this option you can enable support for AMD IOMMU hardware in
-	  your system. An IOMMU is a hardware component which provides
-	  remapping of DMA memory accesses from devices. With an AMD IOMMU you
-	  can isolate the the DMA memory of different devices and protect the
-	  system from misbehaving device drivers or hardware.
-
-	  You can find out if your system has an AMD IOMMU if you look into
-	  your BIOS for an option to enable it or if you have an IVRS ACPI
-	  table.
-
-config AMD_IOMMU_STATS
-	bool "Export AMD IOMMU statistics to debugfs"
-	depends on AMD_IOMMU
-	select DEBUG_FS
-	---help---
-	  This option enables code in the AMD IOMMU driver to collect various
-	  statistics about whats happening in the driver and exports that
-	  information to userspace via debugfs.
-	  If unsure, say N.
-
 # need this always selected by IOMMU for the VIA workaround
 config SWIOTLB
 	def_bool y if X86_64
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 90b06d4daee..aef02989c93 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -123,7 +123,7 @@ ifeq ($(CONFIG_X86_64),y)
 
 	obj-$(CONFIG_GART_IOMMU)	+= amd_gart_64.o aperture_64.o
 	obj-$(CONFIG_CALGARY_IOMMU)	+= pci-calgary_64.o tce_64.o
-	obj-$(CONFIG_AMD_IOMMU)		+= amd_iommu_init.o amd_iommu.o
+	obj-$(CONFIG_AMD_IOMMU)		+= amd_iommu_init.o
 
 	obj-$(CONFIG_PCI_MMCONFIG)	+= mmconf-fam10h_64.o
 	obj-y				+= vsmp_64.o
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
deleted file mode 100644
index 7c3a95e54ec..00000000000
--- a/arch/x86/kernel/amd_iommu.c
+++ /dev/null
@@ -1,2764 +0,0 @@
-/*
- * Copyright (C) 2007-2010 Advanced Micro Devices, Inc.
- * Author: Joerg Roedel <joerg.roedel@amd.com>
- *         Leo Duran <leo.duran@amd.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published
- * by the Free Software Foundation.
- *
- * This program is distributed in the hope that 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
- */
-
-#include <linux/pci.h>
-#include <linux/pci-ats.h>
-#include <linux/bitmap.h>
-#include <linux/slab.h>
-#include <linux/debugfs.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-mapping.h>
-#include <linux/iommu-helper.h>
-#include <linux/iommu.h>
-#include <linux/delay.h>
-#include <asm/proto.h>
-#include <asm/iommu.h>
-#include <asm/gart.h>
-#include <asm/dma.h>
-#include <asm/amd_iommu_proto.h>
-#include <asm/amd_iommu_types.h>
-#include <asm/amd_iommu.h>
-
-#define CMD_SET_TYPE(cmd, t) ((cmd)->data[1] |= ((t) << 28))
-
-#define LOOP_TIMEOUT	100000
-
-static DEFINE_RWLOCK(amd_iommu_devtable_lock);
-
-/* A list of preallocated protection domains */
-static LIST_HEAD(iommu_pd_list);
-static DEFINE_SPINLOCK(iommu_pd_list_lock);
-
-/*
- * Domain for untranslated devices - only allocated
- * if iommu=pt passed on kernel cmd line.
- */
-static struct protection_domain *pt_domain;
-
-static struct iommu_ops amd_iommu_ops;
-
-/*
- * general struct to manage commands send to an IOMMU
- */
-struct iommu_cmd {
-	u32 data[4];
-};
-
-static void update_domain(struct protection_domain *domain);
-
-/****************************************************************************
- *
- * Helper functions
- *
- ****************************************************************************/
-
-static inline u16 get_device_id(struct device *dev)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-
-	return calc_devid(pdev->bus->number, pdev->devfn);
-}
-
-static struct iommu_dev_data *get_dev_data(struct device *dev)
-{
-	return dev->archdata.iommu;
-}
-
-/*
- * In this function the list of preallocated protection domains is traversed to
- * find the domain for a specific device
- */
-static struct dma_ops_domain *find_protection_domain(u16 devid)
-{
-	struct dma_ops_domain *entry, *ret = NULL;
-	unsigned long flags;
-	u16 alias = amd_iommu_alias_table[devid];
-
-	if (list_empty(&iommu_pd_list))
-		return NULL;
-
-	spin_lock_irqsave(&iommu_pd_list_lock, flags);
-
-	list_for_each_entry(entry, &iommu_pd_list, list) {
-		if (entry->target_dev == devid ||
-		    entry->target_dev == alias) {
-			ret = entry;
-			break;
-		}
-	}
-
-	spin_unlock_irqrestore(&iommu_pd_list_lock, flags);
-
-	return ret;
-}
-
-/*
- * This function checks if the driver got a valid device from the caller to
- * avoid dereferencing invalid pointers.
- */
-static bool check_device(struct device *dev)
-{
-	u16 devid;
-
-	if (!dev || !dev->dma_mask)
-		return false;
-
-	/* No device or no PCI device */
-	if (dev->bus != &pci_bus_type)
-		return false;
-
-	devid = get_device_id(dev);
-
-	/* Out of our scope? */
-	if (devid > amd_iommu_last_bdf)
-		return false;
-
-	if (amd_iommu_rlookup_table[devid] == NULL)
-		return false;
-
-	return true;
-}
-
-static int iommu_init_device(struct device *dev)
-{
-	struct iommu_dev_data *dev_data;
-	struct pci_dev *pdev;
-	u16 devid, alias;
-
-	if (dev->archdata.iommu)
-		return 0;
-
-	dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL);
-	if (!dev_data)
-		return -ENOMEM;
-
-	dev_data->dev = dev;
-
-	devid = get_device_id(dev);
-	alias = amd_iommu_alias_table[devid];
-	pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff);
-	if (pdev)
-		dev_data->alias = &pdev->dev;
-	else {
-		kfree(dev_data);
-		return -ENOTSUPP;
-	}
-
-	atomic_set(&dev_data->bind, 0);
-
-	dev->archdata.iommu = dev_data;
-
-
-	return 0;
-}
-
-static void iommu_ignore_device(struct device *dev)
-{
-	u16 devid, alias;
-
-	devid = get_device_id(dev);
-	alias = amd_iommu_alias_table[devid];
-
-	memset(&amd_iommu_dev_table[devid], 0, sizeof(struct dev_table_entry));
-	memset(&amd_iommu_dev_table[alias], 0, sizeof(struct dev_table_entry));
-
-	amd_iommu_rlookup_table[devid] = NULL;
-	amd_iommu_rlookup_table[alias] = NULL;
-}
-
-static void iommu_uninit_device(struct device *dev)
-{
-	kfree(dev->archdata.iommu);
-}
-
-void __init amd_iommu_uninit_devices(void)
-{
-	struct pci_dev *pdev = NULL;
-
-	for_each_pci_dev(pdev) {
-
-		if (!check_device(&pdev->dev))
-			continue;
-
-		iommu_uninit_device(&pdev->dev);
-	}
-}
-
-int __init amd_iommu_init_devices(void)
-{
-	struct pci_dev *pdev = NULL;
-	int ret = 0;
-
-	for_each_pci_dev(pdev) {
-
-		if (!check_device(&pdev->dev))
-			continue;
-
-		ret = iommu_init_device(&pdev->dev);
-		if (ret == -ENOTSUPP)
-			iommu_ignore_device(&pdev->dev);
-		else if (ret)
-			goto out_free;
-	}
-
-	return 0;
-
-out_free:
-
-	amd_iommu_uninit_devices();
-
-	return ret;
-}
-#ifdef CONFIG_AMD_IOMMU_STATS
-
-/*
- * Initialization code for statistics collection
- */
-
-DECLARE_STATS_COUNTER(compl_wait);
-DECLARE_STATS_COUNTER(cnt_map_single);
-DECLARE_STATS_COUNTER(cnt_unmap_single);
-DECLARE_STATS_COUNTER(cnt_map_sg);
-DECLARE_STATS_COUNTER(cnt_unmap_sg);
-DECLARE_STATS_COUNTER(cnt_alloc_coherent);
-DECLARE_STATS_COUNTER(cnt_free_coherent);
-DECLARE_STATS_COUNTER(cross_page);
-DECLARE_STATS_COUNTER(domain_flush_single);
-DECLARE_STATS_COUNTER(domain_flush_all);
-DECLARE_STATS_COUNTER(alloced_io_mem);
-DECLARE_STATS_COUNTER(total_map_requests);
-
-static struct dentry *stats_dir;
-static struct dentry *de_fflush;
-
-static void amd_iommu_stats_add(struct __iommu_counter *cnt)
-{
-	if (stats_dir == NULL)
-		return;
-
-	cnt->dent = debugfs_create_u64(cnt->name, 0444, stats_dir,
-				       &cnt->value);
-}
-
-static void amd_iommu_stats_init(void)
-{
-	stats_dir = debugfs_create_dir("amd-iommu", NULL);
-	if (stats_dir == NULL)
-		return;
-
-	de_fflush  = debugfs_create_bool("fullflush", 0444, stats_dir,
-					 (u32 *)&amd_iommu_unmap_flush);
-
-	amd_iommu_stats_add(&compl_wait);
-	amd_iommu_stats_add(&cnt_map_single);
-	amd_iommu_stats_add(&cnt_unmap_single);
-	amd_iommu_stats_add(&cnt_map_sg);
-	amd_iommu_stats_add(&cnt_unmap_sg);
-	amd_iommu_stats_add(&cnt_alloc_coherent);
-	amd_iommu_stats_add(&cnt_free_coherent);
-	amd_iommu_stats_add(&cross_page);
-	amd_iommu_stats_add(&domain_flush_single);
-	amd_iommu_stats_add(&domain_flush_all);
-	amd_iommu_stats_add(&alloced_io_mem);
-	amd_iommu_stats_add(&total_map_requests);
-}
-
-#endif
-
-/****************************************************************************
- *
- * Interrupt handling functions
- *
- ****************************************************************************/
-
-static void dump_dte_entry(u16 devid)
-{
-	int i;
-
-	for (i = 0; i < 8; ++i)
-		pr_err("AMD-Vi: DTE[%d]: %08x\n", i,
-			amd_iommu_dev_table[devid].data[i]);
-}
-
-static void dump_command(unsigned long phys_addr)
-{
-	struct iommu_cmd *cmd = phys_to_virt(phys_addr);
-	int i;
-
-	for (i = 0; i < 4; ++i)
-		pr_err("AMD-Vi: CMD[%d]: %08x\n", i, cmd->data[i]);
-}
-
-static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
-{
-	u32 *event = __evt;
-	int type  = (event[1] >> EVENT_TYPE_SHIFT)  & EVENT_TYPE_MASK;
-	int devid = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
-	int domid = (event[1] >> EVENT_DOMID_SHIFT) & EVENT_DOMID_MASK;
-	int flags = (event[1] >> EVENT_FLAGS_SHIFT) & EVENT_FLAGS_MASK;
-	u64 address = (u64)(((u64)event[3]) << 32) | event[2];
-
-	printk(KERN_ERR "AMD-Vi: Event logged [");
-
-	switch (type) {
-	case EVENT_TYPE_ILL_DEV:
-		printk("ILLEGAL_DEV_TABLE_ENTRY device=%02x:%02x.%x "
-		       "address=0x%016llx flags=0x%04x]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       address, flags);
-		dump_dte_entry(devid);
-		break;
-	case EVENT_TYPE_IO_FAULT:
-		printk("IO_PAGE_FAULT device=%02x:%02x.%x "
-		       "domain=0x%04x address=0x%016llx flags=0x%04x]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       domid, address, flags);
-		break;
-	case EVENT_TYPE_DEV_TAB_ERR:
-		printk("DEV_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
-		       "address=0x%016llx flags=0x%04x]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       address, flags);
-		break;
-	case EVENT_TYPE_PAGE_TAB_ERR:
-		printk("PAGE_TAB_HARDWARE_ERROR device=%02x:%02x.%x "
-		       "domain=0x%04x address=0x%016llx flags=0x%04x]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       domid, address, flags);
-		break;
-	case EVENT_TYPE_ILL_CMD:
-		printk("ILLEGAL_COMMAND_ERROR address=0x%016llx]\n", address);
-		dump_command(address);
-		break;
-	case EVENT_TYPE_CMD_HARD_ERR:
-		printk("COMMAND_HARDWARE_ERROR address=0x%016llx "
-		       "flags=0x%04x]\n", address, flags);
-		break;
-	case EVENT_TYPE_IOTLB_INV_TO:
-		printk("IOTLB_INV_TIMEOUT device=%02x:%02x.%x "
-		       "address=0x%016llx]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       address);
-		break;
-	case EVENT_TYPE_INV_DEV_REQ:
-		printk("INVALID_DEVICE_REQUEST device=%02x:%02x.%x "
-		       "address=0x%016llx flags=0x%04x]\n",
-		       PCI_BUS(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-		       address, flags);
-		break;
-	default:
-		printk(KERN_ERR "UNKNOWN type=0x%02x]\n", type);
-	}
-}
-
-static void iommu_poll_events(struct amd_iommu *iommu)
-{
-	u32 head, tail;
-	unsigned long flags;
-
-	spin_lock_irqsave(&iommu->lock, flags);
-
-	head = readl(iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
-	tail = readl(iommu->mmio_base + MMIO_EVT_TAIL_OFFSET);
-
-	while (head != tail) {
-		iommu_print_event(iommu, iommu->evt_buf + head);
-		head = (head + EVENT_ENTRY_SIZE) % iommu->evt_buf_size;
-	}
-
-	writel(head, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
-
-	spin_unlock_irqrestore(&iommu->lock, flags);
-}
-
-irqreturn_t amd_iommu_int_thread(int irq, void *data)
-{
-	struct amd_iommu *iommu;
-
-	for_each_iommu(iommu)
-		iommu_poll_events(iommu);
-
-	return IRQ_HANDLED;
-}
-
-irqreturn_t amd_iommu_int_handler(int irq, void *data)
-{
-	return IRQ_WAKE_THREAD;
-}
-
-/****************************************************************************
- *
- * IOMMU command queuing functions
- *
- ****************************************************************************/
-
-static int wait_on_sem(volatile u64 *sem)
-{
-	int i = 0;
-
-	while (*sem == 0 && i < LOOP_TIMEOUT) {
-		udelay(1);
-		i += 1;
-	}
-
-	if (i == LOOP_TIMEOUT) {
-		pr_alert("AMD-Vi: Completion-Wait loop timed out\n");
-		return -EIO;
-	}
-
-	return 0;
-}
-
-static void copy_cmd_to_buffer(struct amd_iommu *iommu,
-			       struct iommu_cmd *cmd,
-			       u32 tail)
-{
-	u8 *target;
-
-	target = iommu->cmd_buf + tail;
-	tail   = (tail + sizeof(*cmd)) % iommu->cmd_buf_size;
-
-	/* Copy command to buffer */
-	memcpy(target, cmd, sizeof(*cmd));
-
-	/* Tell the IOMMU about it */
-	writel(tail, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
-}
-
-static void build_completion_wait(struct iommu_cmd *cmd, u64 address)
-{
-	WARN_ON(address & 0x7ULL);
-
-	memset(cmd, 0, sizeof(*cmd));
-	cmd->data[0] = lower_32_bits(__pa(address)) | CMD_COMPL_WAIT_STORE_MASK;
-	cmd->data[1] = upper_32_bits(__pa(address));
-	cmd->data[2] = 1;
-	CMD_SET_TYPE(cmd, CMD_COMPL_WAIT);
-}
-
-static void build_inv_dte(struct iommu_cmd *cmd, u16 devid)
-{
-	memset(cmd, 0, sizeof(*cmd));
-	cmd->data[0] = devid;
-	CMD_SET_TYPE(cmd, CMD_INV_DEV_ENTRY);
-}
-
-static void build_inv_iommu_pages(struct iommu_cmd *cmd, u64 address,
-				  size_t size, u16 domid, int pde)
-{
-	u64 pages;
-	int s;
-
-	pages = iommu_num_pages(address, size, PAGE_SIZE);
-	s     = 0;
-
-	if (pages > 1) {
-		/*
-		 * If we have to flush more than one page, flush all
-		 * TLB entries for this domain
-		 */
-		address = CMD_INV_IOMMU_ALL_PAGES_ADDRESS;
-		s = 1;
-	}
-
-	address &= PAGE_MASK;
-
-	memset(cmd, 0, sizeof(*cmd));
-	cmd->data[1] |= domid;
-	cmd->data[2]  = lower_32_bits(address);
-	cmd->data[3]  = upper_32_bits(address);
-	CMD_SET_TYPE(cmd, CMD_INV_IOMMU_PAGES);
-	if (s) /* size bit - we flush more than one 4kb page */
-		cmd->data[2] |= CMD_INV_IOMMU_PAGES_SIZE_MASK;
-	if (pde) /* PDE bit - we wan't flush everything not only the PTEs */
-		cmd->data[2] |= CMD_INV_IOMMU_PAGES_PDE_MASK;
-}
-
-static void build_inv_iotlb_pages(struct iommu_cmd *cmd, u16 devid, int qdep,
-				  u64 address, size_t size)
-{
-	u64 pages;
-	int s;
-
-	pages = iommu_num_pages(address, size, PAGE_SIZE);
-	s     = 0;
-
-	if (pages > 1) {
-		/*
-		 * If we have to flush more than one page, flush all
-		 * TLB entries for this domain
-		 */
-		address = CMD_INV_IOMMU_ALL_PAGES_ADDRESS;
-		s = 1;
-	}
-
-	address &= PAGE_MASK;
-
-	memset(cmd, 0, sizeof(*cmd));
-	cmd->data[0]  = devid;
-	cmd->data[0] |= (qdep & 0xff) << 24;
-	cmd->data[1]  = devid;
-	cmd->data[2]  = lower_32_bits(address);
-	cmd->data[3]  = upper_32_bits(address);
-	CMD_SET_TYPE(cmd, CMD_INV_IOTLB_PAGES);
-	if (s)
-		cmd->data[2] |= CMD_INV_IOMMU_PAGES_SIZE_MASK;
-}
-
-static void build_inv_all(struct iommu_cmd *cmd)
-{
-	memset(cmd, 0, sizeof(*cmd));
-	CMD_SET_TYPE(cmd, CMD_INV_ALL);
-}
-
-/*
- * Writes the command to the IOMMUs command buffer and informs the
- * hardware about the new command.
- */
-static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd)
-{
-	u32 left, tail, head, next_tail;
-	unsigned long flags;
-
-	WARN_ON(iommu->cmd_buf_size & CMD_BUFFER_UNINITIALIZED);
-
-again:
-	spin_lock_irqsave(&iommu->lock, flags);
-
-	head      = readl(iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
-	tail      = readl(iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
-	next_tail = (tail + sizeof(*cmd)) % iommu->cmd_buf_size;
-	left      = (head - next_tail) % iommu->cmd_buf_size;
-
-	if (left <= 2) {
-		struct iommu_cmd sync_cmd;
-		volatile u64 sem = 0;
-		int ret;
-
-		build_completion_wait(&sync_cmd, (u64)&sem);
-		copy_cmd_to_buffer(iommu, &sync_cmd, tail);
-
-		spin_unlock_irqrestore(&iommu->lock, flags);
-
-		if ((ret = wait_on_sem(&sem)) != 0)
-			return ret;
-
-		goto again;
-	}
-
-	copy_cmd_to_buffer(iommu, cmd, tail);
-
-	/* We need to sync now to make sure all commands are processed */
-	iommu->need_sync = true;
-
-	spin_unlock_irqrestore(&iommu->lock, flags);
-
-	return 0;
-}
-
-/*
- * This function queues a completion wait command into the command
- * buffer of an IOMMU
- */
-static int iommu_completion_wait(struct amd_iommu *iommu)
-{
-	struct iommu_cmd cmd;
-	volatile u64 sem = 0;
-	int ret;
-
-	if (!iommu->need_sync)
-		return 0;
-
-	build_completion_wait(&cmd, (u64)&sem);
-
-	ret = iommu_queue_command(iommu, &cmd);
-	if (ret)
-		return ret;
-
-	return wait_on_sem(&sem);
-}
-
-static int iommu_flush_dte(struct amd_iommu *iommu, u16 devid)
-{
-	struct iommu_cmd cmd;
-
-	build_inv_dte(&cmd, devid);
-
-	return iommu_queue_command(iommu, &cmd);
-}
-
-static void iommu_flush_dte_all(struct amd_iommu *iommu)
-{
-	u32 devid;
-
-	for (devid = 0; devid <= 0xffff; ++devid)
-		iommu_flush_dte(iommu, devid);
-
-	iommu_completion_wait(iommu);
-}
-
-/*
- * This function uses heavy locking and may disable irqs for some time. But
- * this is no issue because it is only called during resume.
- */
-static void iommu_flush_tlb_all(struct amd_iommu *iommu)
-{
-	u32 dom_id;
-
-	for (dom_id = 0; dom_id <= 0xffff; ++dom_id) {
-		struct iommu_cmd cmd;
-		build_inv_iommu_pages(&cmd, 0, CMD_INV_IOMMU_ALL_PAGES_ADDRESS,
-				      dom_id, 1);
-		iommu_queue_command(iommu, &cmd);
-	}
-
-	iommu_completion_wait(iommu);
-}
-
-static void iommu_flush_all(struct amd_iommu *iommu)
-{
-	struct iommu_cmd cmd;
-
-	build_inv_all(&cmd);
-
-	iommu_queue_command(iommu, &cmd);
-	iommu_completion_wait(iommu);
-}
-
-void iommu_flush_all_caches(struct amd_iommu *iommu)
-{
-	if (iommu_feature(iommu, FEATURE_IA)) {
-		iommu_flush_all(iommu);
-	} else {
-		iommu_flush_dte_all(iommu);
-		iommu_flush_tlb_all(iommu);
-	}
-}
-
-/*
- * Command send function for flushing on-device TLB
- */
-static int device_flush_iotlb(struct device *dev, u64 address, size_t size)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	struct amd_iommu *iommu;
-	struct iommu_cmd cmd;
-	u16 devid;
-	int qdep;
-
-	qdep  = pci_ats_queue_depth(pdev);
-	devid = get_device_id(dev);
-	iommu = amd_iommu_rlookup_table[devid];
-
-	build_inv_iotlb_pages(&cmd, devid, qdep, address, size);
-
-	return iommu_queue_command(iommu, &cmd);
-}
-
-/*
- * Command send function for invalidating a device table entry
- */
-static int device_flush_dte(struct device *dev)
-{
-	struct amd_iommu *iommu;
-	struct pci_dev *pdev;
-	u16 devid;
-	int ret;
-
-	pdev  = to_pci_dev(dev);
-	devid = get_device_id(dev);
-	iommu = amd_iommu_rlookup_table[devid];
-
-	ret = iommu_flush_dte(iommu, devid);
-	if (ret)
-		return ret;
-
-	if (pci_ats_enabled(pdev))
-		ret = device_flush_iotlb(dev, 0, ~0UL);
-
-	return ret;
-}
-
-/*
- * TLB invalidation function which is called from the mapping functions.
- * It invalidates a single PTE if the range to flush is within a single
- * page. Otherwise it flushes the whole TLB of the IOMMU.
- */
-static void __domain_flush_pages(struct protection_domain *domain,
-				 u64 address, size_t size, int pde)
-{
-	struct iommu_dev_data *dev_data;
-	struct iommu_cmd cmd;
-	int ret = 0, i;
-
-	build_inv_iommu_pages(&cmd, address, size, domain->id, pde);
-
-	for (i = 0; i < amd_iommus_present; ++i) {
-		if (!domain->dev_iommu[i])
-			continue;
-
-		/*
-		 * Devices of this domain are behind this IOMMU
-		 * We need a TLB flush
-		 */
-		ret |= iommu_queue_command(amd_iommus[i], &cmd);
-	}
-
-	list_for_each_entry(dev_data, &domain->dev_list, list) {
-		struct pci_dev *pdev = to_pci_dev(dev_data->dev);
-
-		if (!pci_ats_enabled(pdev))
-			continue;
-
-		ret |= device_flush_iotlb(dev_data->dev, address, size);
-	}
-
-	WARN_ON(ret);
-}
-
-static void domain_flush_pages(struct protection_domain *domain,
-			       u64 address, size_t size)
-{
-	__domain_flush_pages(domain, address, size, 0);
-}
-
-/* Flush the whole IO/TLB for a given protection domain */
-static void domain_flush_tlb(struct protection_domain *domain)
-{
-	__domain_flush_pages(domain, 0, CMD_INV_IOMMU_ALL_PAGES_ADDRESS, 0);
-}
-
-/* Flush the whole IO/TLB for a given protection domain - including PDE */
-static void domain_flush_tlb_pde(struct protection_domain *domain)
-{
-	__domain_flush_pages(domain, 0, CMD_INV_IOMMU_ALL_PAGES_ADDRESS, 1);
-}
-
-static void domain_flush_complete(struct protection_domain *domain)
-{
-	int i;
-
-	for (i = 0; i < amd_iommus_present; ++i) {
-		if (!domain->dev_iommu[i])
-			continue;
-
-		/*
-		 * Devices of this domain are behind this IOMMU
-		 * We need to wait for completion of all commands.
-		 */
-		iommu_completion_wait(amd_iommus[i]);
-	}
-}
-
-
-/*
- * This function flushes the DTEs for all devices in domain
- */
-static void domain_flush_devices(struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data;
-	unsigned long flags;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	list_for_each_entry(dev_data, &domain->dev_list, list)
-		device_flush_dte(dev_data->dev);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-}
-
-/****************************************************************************
- *
- * The functions below are used the create the page table mappings for
- * unity mapped regions.
- *
- ****************************************************************************/
-
-/*
- * This function is used to add another level to an IO page table. Adding
- * another level increases the size of the address space by 9 bits to a size up
- * to 64 bits.
- */
-static bool increase_address_space(struct protection_domain *domain,
-				   gfp_t gfp)
-{
-	u64 *pte;
-
-	if (domain->mode == PAGE_MODE_6_LEVEL)
-		/* address space already 64 bit large */
-		return false;
-
-	pte = (void *)get_zeroed_page(gfp);
-	if (!pte)
-		return false;
-
-	*pte             = PM_LEVEL_PDE(domain->mode,
-					virt_to_phys(domain->pt_root));
-	domain->pt_root  = pte;
-	domain->mode    += 1;
-	domain->updated  = true;
-
-	return true;
-}
-
-static u64 *alloc_pte(struct protection_domain *domain,
-		      unsigned long address,
-		      unsigned long page_size,
-		      u64 **pte_page,
-		      gfp_t gfp)
-{
-	int level, end_lvl;
-	u64 *pte, *page;
-
-	BUG_ON(!is_power_of_2(page_size));
-
-	while (address > PM_LEVEL_SIZE(domain->mode))
-		increase_address_space(domain, gfp);
-
-	level   = domain->mode - 1;
-	pte     = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
-	address = PAGE_SIZE_ALIGN(address, page_size);
-	end_lvl = PAGE_SIZE_LEVEL(page_size);
-
-	while (level > end_lvl) {
-		if (!IOMMU_PTE_PRESENT(*pte)) {
-			page = (u64 *)get_zeroed_page(gfp);
-			if (!page)
-				return NULL;
-			*pte = PM_LEVEL_PDE(level, virt_to_phys(page));
-		}
-
-		/* No level skipping support yet */
-		if (PM_PTE_LEVEL(*pte) != level)
-			return NULL;
-
-		level -= 1;
-
-		pte = IOMMU_PTE_PAGE(*pte);
-
-		if (pte_page && level == end_lvl)
-			*pte_page = pte;
-
-		pte = &pte[PM_LEVEL_INDEX(level, address)];
-	}
-
-	return pte;
-}
-
-/*
- * This function checks if there is a PTE for a given dma address. If
- * there is one, it returns the pointer to it.
- */
-static u64 *fetch_pte(struct protection_domain *domain, unsigned long address)
-{
-	int level;
-	u64 *pte;
-
-	if (address > PM_LEVEL_SIZE(domain->mode))
-		return NULL;
-
-	level   =  domain->mode - 1;
-	pte     = &domain->pt_root[PM_LEVEL_INDEX(level, address)];
-
-	while (level > 0) {
-
-		/* Not Present */
-		if (!IOMMU_PTE_PRESENT(*pte))
-			return NULL;
-
-		/* Large PTE */
-		if (PM_PTE_LEVEL(*pte) == 0x07) {
-			unsigned long pte_mask, __pte;
-
-			/*
-			 * If we have a series of large PTEs, make
-			 * sure to return a pointer to the first one.
-			 */
-			pte_mask = PTE_PAGE_SIZE(*pte);
-			pte_mask = ~((PAGE_SIZE_PTE_COUNT(pte_mask) << 3) - 1);
-			__pte    = ((unsigned long)pte) & pte_mask;
-
-			return (u64 *)__pte;
-		}
-
-		/* No level skipping support yet */
-		if (PM_PTE_LEVEL(*pte) != level)
-			return NULL;
-
-		level -= 1;
-
-		/* Walk to the next level */
-		pte = IOMMU_PTE_PAGE(*pte);
-		pte = &pte[PM_LEVEL_INDEX(level, address)];
-	}
-
-	return pte;
-}
-
-/*
- * Generic mapping functions. It maps a physical address into a DMA
- * address space. It allocates the page table pages if necessary.
- * In the future it can be extended to a generic mapping function
- * supporting all features of AMD IOMMU page tables like level skipping
- * and full 64 bit address spaces.
- */
-static int iommu_map_page(struct protection_domain *dom,
-			  unsigned long bus_addr,
-			  unsigned long phys_addr,
-			  int prot,
-			  unsigned long page_size)
-{
-	u64 __pte, *pte;
-	int i, count;
-
-	if (!(prot & IOMMU_PROT_MASK))
-		return -EINVAL;
-
-	bus_addr  = PAGE_ALIGN(bus_addr);
-	phys_addr = PAGE_ALIGN(phys_addr);
-	count     = PAGE_SIZE_PTE_COUNT(page_size);
-	pte       = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);
-
-	for (i = 0; i < count; ++i)
-		if (IOMMU_PTE_PRESENT(pte[i]))
-			return -EBUSY;
-
-	if (page_size > PAGE_SIZE) {
-		__pte = PAGE_SIZE_PTE(phys_addr, page_size);
-		__pte |= PM_LEVEL_ENC(7) | IOMMU_PTE_P | IOMMU_PTE_FC;
-	} else
-		__pte = phys_addr | IOMMU_PTE_P | IOMMU_PTE_FC;
-
-	if (prot & IOMMU_PROT_IR)
-		__pte |= IOMMU_PTE_IR;
-	if (prot & IOMMU_PROT_IW)
-		__pte |= IOMMU_PTE_IW;
-
-	for (i = 0; i < count; ++i)
-		pte[i] = __pte;
-
-	update_domain(dom);
-
-	return 0;
-}
-
-static unsigned long iommu_unmap_page(struct protection_domain *dom,
-				      unsigned long bus_addr,
-				      unsigned long page_size)
-{
-	unsigned long long unmap_size, unmapped;
-	u64 *pte;
-
-	BUG_ON(!is_power_of_2(page_size));
-
-	unmapped = 0;
-
-	while (unmapped < page_size) {
-
-		pte = fetch_pte(dom, bus_addr);
-
-		if (!pte) {
-			/*
-			 * No PTE for this address
-			 * move forward in 4kb steps
-			 */
-			unmap_size = PAGE_SIZE;
-		} else if (PM_PTE_LEVEL(*pte) == 0) {
-			/* 4kb PTE found for this address */
-			unmap_size = PAGE_SIZE;
-			*pte       = 0ULL;
-		} else {
-			int count, i;
-
-			/* Large PTE found which maps this address */
-			unmap_size = PTE_PAGE_SIZE(*pte);
-			count      = PAGE_SIZE_PTE_COUNT(unmap_size);
-			for (i = 0; i < count; i++)
-				pte[i] = 0ULL;
-		}
-
-		bus_addr  = (bus_addr & ~(unmap_size - 1)) + unmap_size;
-		unmapped += unmap_size;
-	}
-
-	BUG_ON(!is_power_of_2(unmapped));
-
-	return unmapped;
-}
-
-/*
- * This function checks if a specific unity mapping entry is needed for
- * this specific IOMMU.
- */
-static int iommu_for_unity_map(struct amd_iommu *iommu,
-			       struct unity_map_entry *entry)
-{
-	u16 bdf, i;
-
-	for (i = entry->devid_start; i <= entry->devid_end; ++i) {
-		bdf = amd_iommu_alias_table[i];
-		if (amd_iommu_rlookup_table[bdf] == iommu)
-			return 1;
-	}
-
-	return 0;
-}
-
-/*
- * This function actually applies the mapping to the page table of the
- * dma_ops domain.
- */
-static int dma_ops_unity_map(struct dma_ops_domain *dma_dom,
-			     struct unity_map_entry *e)
-{
-	u64 addr;
-	int ret;
-
-	for (addr = e->address_start; addr < e->address_end;
-	     addr += PAGE_SIZE) {
-		ret = iommu_map_page(&dma_dom->domain, addr, addr, e->prot,
-				     PAGE_SIZE);
-		if (ret)
-			return ret;
-		/*
-		 * if unity mapping is in aperture range mark the page
-		 * as allocated in the aperture
-		 */
-		if (addr < dma_dom->aperture_size)
-			__set_bit(addr >> PAGE_SHIFT,
-				  dma_dom->aperture[0]->bitmap);
-	}
-
-	return 0;
-}
-
-/*
- * Init the unity mappings for a specific IOMMU in the system
- *
- * Basically iterates over all unity mapping entries and applies them to
- * the default domain DMA of that IOMMU if necessary.
- */
-static int iommu_init_unity_mappings(struct amd_iommu *iommu)
-{
-	struct unity_map_entry *entry;
-	int ret;
-
-	list_for_each_entry(entry, &amd_iommu_unity_map, list) {
-		if (!iommu_for_unity_map(iommu, entry))
-			continue;
-		ret = dma_ops_unity_map(iommu->default_dom, entry);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
-/*
- * Inits the unity mappings required for a specific device
- */
-static int init_unity_mappings_for_device(struct dma_ops_domain *dma_dom,
-					  u16 devid)
-{
-	struct unity_map_entry *e;
-	int ret;
-
-	list_for_each_entry(e, &amd_iommu_unity_map, list) {
-		if (!(devid >= e->devid_start && devid <= e->devid_end))
-			continue;
-		ret = dma_ops_unity_map(dma_dom, e);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-
-/****************************************************************************
- *
- * The next functions belong to the address allocator for the dma_ops
- * interface functions. They work like the allocators in the other IOMMU
- * drivers. Its basically a bitmap which marks the allocated pages in
- * the aperture. Maybe it could be enhanced in the future to a more
- * efficient allocator.
- *
- ****************************************************************************/
-
-/*
- * The address allocator core functions.
- *
- * called with domain->lock held
- */
-
-/*
- * Used to reserve address ranges in the aperture (e.g. for exclusion
- * ranges.
- */
-static void dma_ops_reserve_addresses(struct dma_ops_domain *dom,
-				      unsigned long start_page,
-				      unsigned int pages)
-{
-	unsigned int i, last_page = dom->aperture_size >> PAGE_SHIFT;
-
-	if (start_page + pages > last_page)
-		pages = last_page - start_page;
-
-	for (i = start_page; i < start_page + pages; ++i) {
-		int index = i / APERTURE_RANGE_PAGES;
-		int page  = i % APERTURE_RANGE_PAGES;
-		__set_bit(page, dom->aperture[index]->bitmap);
-	}
-}
-
-/*
- * This function is used to add a new aperture range to an existing
- * aperture in case of dma_ops domain allocation or address allocation
- * failure.
- */
-static int alloc_new_range(struct dma_ops_domain *dma_dom,
-			   bool populate, gfp_t gfp)
-{
-	int index = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
-	struct amd_iommu *iommu;
-	unsigned long i;
-
-#ifdef CONFIG_IOMMU_STRESS
-	populate = false;
-#endif
-
-	if (index >= APERTURE_MAX_RANGES)
-		return -ENOMEM;
-
-	dma_dom->aperture[index] = kzalloc(sizeof(struct aperture_range), gfp);
-	if (!dma_dom->aperture[index])
-		return -ENOMEM;
-
-	dma_dom->aperture[index]->bitmap = (void *)get_zeroed_page(gfp);
-	if (!dma_dom->aperture[index]->bitmap)
-		goto out_free;
-
-	dma_dom->aperture[index]->offset = dma_dom->aperture_size;
-
-	if (populate) {
-		unsigned long address = dma_dom->aperture_size;
-		int i, num_ptes = APERTURE_RANGE_PAGES / 512;
-		u64 *pte, *pte_page;
-
-		for (i = 0; i < num_ptes; ++i) {
-			pte = alloc_pte(&dma_dom->domain, address, PAGE_SIZE,
-					&pte_page, gfp);
-			if (!pte)
-				goto out_free;
-
-			dma_dom->aperture[index]->pte_pages[i] = pte_page;
-
-			address += APERTURE_RANGE_SIZE / 64;
-		}
-	}
-
-	dma_dom->aperture_size += APERTURE_RANGE_SIZE;
-
-	/* Initialize the exclusion range if necessary */
-	for_each_iommu(iommu) {
-		if (iommu->exclusion_start &&
-		    iommu->exclusion_start >= dma_dom->aperture[index]->offset
-		    && iommu->exclusion_start < dma_dom->aperture_size) {
-			unsigned long startpage;
-			int pages = iommu_num_pages(iommu->exclusion_start,
-						    iommu->exclusion_length,
-						    PAGE_SIZE);
-			startpage = iommu->exclusion_start >> PAGE_SHIFT;
-			dma_ops_reserve_addresses(dma_dom, startpage, pages);
-		}
-	}
-
-	/*
-	 * Check for areas already mapped as present in the new aperture
-	 * range and mark those pages as reserved in the allocator. Such
-	 * mappings may already exist as a result of requested unity
-	 * mappings for devices.
-	 */
-	for (i = dma_dom->aperture[index]->offset;
-	     i < dma_dom->aperture_size;
-	     i += PAGE_SIZE) {
-		u64 *pte = fetch_pte(&dma_dom->domain, i);
-		if (!pte || !IOMMU_PTE_PRESENT(*pte))
-			continue;
-
-		dma_ops_reserve_addresses(dma_dom, i << PAGE_SHIFT, 1);
-	}
-
-	update_domain(&dma_dom->domain);
-
-	return 0;
-
-out_free:
-	update_domain(&dma_dom->domain);
-
-	free_page((unsigned long)dma_dom->aperture[index]->bitmap);
-
-	kfree(dma_dom->aperture[index]);
-	dma_dom->aperture[index] = NULL;
-
-	return -ENOMEM;
-}
-
-static unsigned long dma_ops_area_alloc(struct device *dev,
-					struct dma_ops_domain *dom,
-					unsigned int pages,
-					unsigned long align_mask,
-					u64 dma_mask,
-					unsigned long start)
-{
-	unsigned long next_bit = dom->next_address % APERTURE_RANGE_SIZE;
-	int max_index = dom->aperture_size >> APERTURE_RANGE_SHIFT;
-	int i = start >> APERTURE_RANGE_SHIFT;
-	unsigned long boundary_size;
-	unsigned long address = -1;
-	unsigned long limit;
-
-	next_bit >>= PAGE_SHIFT;
-
-	boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
-			PAGE_SIZE) >> PAGE_SHIFT;
-
-	for (;i < max_index; ++i) {
-		unsigned long offset = dom->aperture[i]->offset >> PAGE_SHIFT;
-
-		if (dom->aperture[i]->offset >= dma_mask)
-			break;
-
-		limit = iommu_device_max_index(APERTURE_RANGE_PAGES, offset,
-					       dma_mask >> PAGE_SHIFT);
-
-		address = iommu_area_alloc(dom->aperture[i]->bitmap,
-					   limit, next_bit, pages, 0,
-					    boundary_size, align_mask);
-		if (address != -1) {
-			address = dom->aperture[i]->offset +
-				  (address << PAGE_SHIFT);
-			dom->next_address = address + (pages << PAGE_SHIFT);
-			break;
-		}
-
-		next_bit = 0;
-	}
-
-	return address;
-}
-
-static unsigned long dma_ops_alloc_addresses(struct device *dev,
-					     struct dma_ops_domain *dom,
-					     unsigned int pages,
-					     unsigned long align_mask,
-					     u64 dma_mask)
-{
-	unsigned long address;
-
-#ifdef CONFIG_IOMMU_STRESS
-	dom->next_address = 0;
-	dom->need_flush = true;
-#endif
-
-	address = dma_ops_area_alloc(dev, dom, pages, align_mask,
-				     dma_mask, dom->next_address);
-
-	if (address == -1) {
-		dom->next_address = 0;
-		address = dma_ops_area_alloc(dev, dom, pages, align_mask,
-					     dma_mask, 0);
-		dom->need_flush = true;
-	}
-
-	if (unlikely(address == -1))
-		address = DMA_ERROR_CODE;
-
-	WARN_ON((address + (PAGE_SIZE*pages)) > dom->aperture_size);
-
-	return address;
-}
-
-/*
- * The address free function.
- *
- * called with domain->lock held
- */
-static void dma_ops_free_addresses(struct dma_ops_domain *dom,
-				   unsigned long address,
-				   unsigned int pages)
-{
-	unsigned i = address >> APERTURE_RANGE_SHIFT;
-	struct aperture_range *range = dom->aperture[i];
-
-	BUG_ON(i >= APERTURE_MAX_RANGES || range == NULL);
-
-#ifdef CONFIG_IOMMU_STRESS
-	if (i < 4)
-		return;
-#endif
-
-	if (address >= dom->next_address)
-		dom->need_flush = true;
-
-	address = (address % APERTURE_RANGE_SIZE) >> PAGE_SHIFT;
-
-	bitmap_clear(range->bitmap, address, pages);
-
-}
-
-/****************************************************************************
- *
- * The next functions belong to the domain allocation. A domain is
- * allocated for every IOMMU as the default domain. If device isolation
- * is enabled, every device get its own domain. The most important thing
- * about domains is the page table mapping the DMA address space they
- * contain.
- *
- ****************************************************************************/
-
-/*
- * This function adds a protection domain to the global protection domain list
- */
-static void add_domain_to_list(struct protection_domain *domain)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&amd_iommu_pd_lock, flags);
-	list_add(&domain->list, &amd_iommu_pd_list);
-	spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
-}
-
-/*
- * This function removes a protection domain to the global
- * protection domain list
- */
-static void del_domain_from_list(struct protection_domain *domain)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&amd_iommu_pd_lock, flags);
-	list_del(&domain->list);
-	spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
-}
-
-static u16 domain_id_alloc(void)
-{
-	unsigned long flags;
-	int id;
-
-	write_lock_irqsave(&amd_iommu_devtable_lock, flags);
-	id = find_first_zero_bit(amd_iommu_pd_alloc_bitmap, MAX_DOMAIN_ID);
-	BUG_ON(id == 0);
-	if (id > 0 && id < MAX_DOMAIN_ID)
-		__set_bit(id, amd_iommu_pd_alloc_bitmap);
-	else
-		id = 0;
-	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-
-	return id;
-}
-
-static void domain_id_free(int id)
-{
-	unsigned long flags;
-
-	write_lock_irqsave(&amd_iommu_devtable_lock, flags);
-	if (id > 0 && id < MAX_DOMAIN_ID)
-		__clear_bit(id, amd_iommu_pd_alloc_bitmap);
-	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-}
-
-static void free_pagetable(struct protection_domain *domain)
-{
-	int i, j;
-	u64 *p1, *p2, *p3;
-
-	p1 = domain->pt_root;
-
-	if (!p1)
-		return;
-
-	for (i = 0; i < 512; ++i) {
-		if (!IOMMU_PTE_PRESENT(p1[i]))
-			continue;
-
-		p2 = IOMMU_PTE_PAGE(p1[i]);
-		for (j = 0; j < 512; ++j) {
-			if (!IOMMU_PTE_PRESENT(p2[j]))
-				continue;
-			p3 = IOMMU_PTE_PAGE(p2[j]);
-			free_page((unsigned long)p3);
-		}
-
-		free_page((unsigned long)p2);
-	}
-
-	free_page((unsigned long)p1);
-
-	domain->pt_root = NULL;
-}
-
-/*
- * Free a domain, only used if something went wrong in the
- * allocation path and we need to free an already allocated page table
- */
-static void dma_ops_domain_free(struct dma_ops_domain *dom)
-{
-	int i;
-
-	if (!dom)
-		return;
-
-	del_domain_from_list(&dom->domain);
-
-	free_pagetable(&dom->domain);
-
-	for (i = 0; i < APERTURE_MAX_RANGES; ++i) {
-		if (!dom->aperture[i])
-			continue;
-		free_page((unsigned long)dom->aperture[i]->bitmap);
-		kfree(dom->aperture[i]);
-	}
-
-	kfree(dom);
-}
-
-/*
- * Allocates a new protection domain usable for the dma_ops functions.
- * It also initializes the page table and the address allocator data
- * structures required for the dma_ops interface
- */
-static struct dma_ops_domain *dma_ops_domain_alloc(void)
-{
-	struct dma_ops_domain *dma_dom;
-
-	dma_dom = kzalloc(sizeof(struct dma_ops_domain), GFP_KERNEL);
-	if (!dma_dom)
-		return NULL;
-
-	spin_lock_init(&dma_dom->domain.lock);
-
-	dma_dom->domain.id = domain_id_alloc();
-	if (dma_dom->domain.id == 0)
-		goto free_dma_dom;
-	INIT_LIST_HEAD(&dma_dom->domain.dev_list);
-	dma_dom->domain.mode = PAGE_MODE_2_LEVEL;
-	dma_dom->domain.pt_root = (void *)get_zeroed_page(GFP_KERNEL);
-	dma_dom->domain.flags = PD_DMA_OPS_MASK;
-	dma_dom->domain.priv = dma_dom;
-	if (!dma_dom->domain.pt_root)
-		goto free_dma_dom;
-
-	dma_dom->need_flush = false;
-	dma_dom->target_dev = 0xffff;
-
-	add_domain_to_list(&dma_dom->domain);
-
-	if (alloc_new_range(dma_dom, true, GFP_KERNEL))
-		goto free_dma_dom;
-
-	/*
-	 * mark the first page as allocated so we never return 0 as
-	 * a valid dma-address. So we can use 0 as error value
-	 */
-	dma_dom->aperture[0]->bitmap[0] = 1;
-	dma_dom->next_address = 0;
-
-
-	return dma_dom;
-
-free_dma_dom:
-	dma_ops_domain_free(dma_dom);
-
-	return NULL;
-}
-
-/*
- * little helper function to check whether a given protection domain is a
- * dma_ops domain
- */
-static bool dma_ops_domain(struct protection_domain *domain)
-{
-	return domain->flags & PD_DMA_OPS_MASK;
-}
-
-static void set_dte_entry(u16 devid, struct protection_domain *domain, bool ats)
-{
-	u64 pte_root = virt_to_phys(domain->pt_root);
-	u32 flags = 0;
-
-	pte_root |= (domain->mode & DEV_ENTRY_MODE_MASK)
-		    << DEV_ENTRY_MODE_SHIFT;
-	pte_root |= IOMMU_PTE_IR | IOMMU_PTE_IW | IOMMU_PTE_P | IOMMU_PTE_TV;
-
-	if (ats)
-		flags |= DTE_FLAG_IOTLB;
-
-	amd_iommu_dev_table[devid].data[3] |= flags;
-	amd_iommu_dev_table[devid].data[2]  = domain->id;
-	amd_iommu_dev_table[devid].data[1]  = upper_32_bits(pte_root);
-	amd_iommu_dev_table[devid].data[0]  = lower_32_bits(pte_root);
-}
-
-static void clear_dte_entry(u16 devid)
-{
-	/* remove entry from the device table seen by the hardware */
-	amd_iommu_dev_table[devid].data[0] = IOMMU_PTE_P | IOMMU_PTE_TV;
-	amd_iommu_dev_table[devid].data[1] = 0;
-	amd_iommu_dev_table[devid].data[2] = 0;
-
-	amd_iommu_apply_erratum_63(devid);
-}
-
-static void do_attach(struct device *dev, struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data;
-	struct amd_iommu *iommu;
-	struct pci_dev *pdev;
-	bool ats = false;
-	u16 devid;
-
-	devid    = get_device_id(dev);
-	iommu    = amd_iommu_rlookup_table[devid];
-	dev_data = get_dev_data(dev);
-	pdev     = to_pci_dev(dev);
-
-	if (amd_iommu_iotlb_sup)
-		ats = pci_ats_enabled(pdev);
-
-	/* Update data structures */
-	dev_data->domain = domain;
-	list_add(&dev_data->list, &domain->dev_list);
-	set_dte_entry(devid, domain, ats);
-
-	/* Do reference counting */
-	domain->dev_iommu[iommu->index] += 1;
-	domain->dev_cnt                 += 1;
-
-	/* Flush the DTE entry */
-	device_flush_dte(dev);
-}
-
-static void do_detach(struct device *dev)
-{
-	struct iommu_dev_data *dev_data;
-	struct amd_iommu *iommu;
-	u16 devid;
-
-	devid    = get_device_id(dev);
-	iommu    = amd_iommu_rlookup_table[devid];
-	dev_data = get_dev_data(dev);
-
-	/* decrease reference counters */
-	dev_data->domain->dev_iommu[iommu->index] -= 1;
-	dev_data->domain->dev_cnt                 -= 1;
-
-	/* Update data structures */
-	dev_data->domain = NULL;
-	list_del(&dev_data->list);
-	clear_dte_entry(devid);
-
-	/* Flush the DTE entry */
-	device_flush_dte(dev);
-}
-
-/*
- * If a device is not yet associated with a domain, this function does
- * assigns it visible for the hardware
- */
-static int __attach_device(struct device *dev,
-			   struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data, *alias_data;
-	int ret;
-
-	dev_data   = get_dev_data(dev);
-	alias_data = get_dev_data(dev_data->alias);
-
-	if (!alias_data)
-		return -EINVAL;
-
-	/* lock domain */
-	spin_lock(&domain->lock);
-
-	/* Some sanity checks */
-	ret = -EBUSY;
-	if (alias_data->domain != NULL &&
-	    alias_data->domain != domain)
-		goto out_unlock;
-
-	if (dev_data->domain != NULL &&
-	    dev_data->domain != domain)
-		goto out_unlock;
-
-	/* Do real assignment */
-	if (dev_data->alias != dev) {
-		alias_data = get_dev_data(dev_data->alias);
-		if (alias_data->domain == NULL)
-			do_attach(dev_data->alias, domain);
-
-		atomic_inc(&alias_data->bind);
-	}
-
-	if (dev_data->domain == NULL)
-		do_attach(dev, domain);
-
-	atomic_inc(&dev_data->bind);
-
-	ret = 0;
-
-out_unlock:
-
-	/* ready */
-	spin_unlock(&domain->lock);
-
-	return ret;
-}
-
-/*
- * If a device is not yet associated with a domain, this function does
- * assigns it visible for the hardware
- */
-static int attach_device(struct device *dev,
-			 struct protection_domain *domain)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	unsigned long flags;
-	int ret;
-
-	if (amd_iommu_iotlb_sup)
-		pci_enable_ats(pdev, PAGE_SHIFT);
-
-	write_lock_irqsave(&amd_iommu_devtable_lock, flags);
-	ret = __attach_device(dev, domain);
-	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-
-	/*
-	 * We might boot into a crash-kernel here. The crashed kernel
-	 * left the caches in the IOMMU dirty. So we have to flush
-	 * here to evict all dirty stuff.
-	 */
-	domain_flush_tlb_pde(domain);
-
-	return ret;
-}
-
-/*
- * Removes a device from a protection domain (unlocked)
- */
-static void __detach_device(struct device *dev)
-{
-	struct iommu_dev_data *dev_data = get_dev_data(dev);
-	struct iommu_dev_data *alias_data;
-	struct protection_domain *domain;
-	unsigned long flags;
-
-	BUG_ON(!dev_data->domain);
-
-	domain = dev_data->domain;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	if (dev_data->alias != dev) {
-		alias_data = get_dev_data(dev_data->alias);
-		if (atomic_dec_and_test(&alias_data->bind))
-			do_detach(dev_data->alias);
-	}
-
-	if (atomic_dec_and_test(&dev_data->bind))
-		do_detach(dev);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	/*
-	 * If we run in passthrough mode the device must be assigned to the
-	 * passthrough domain if it is detached from any other domain.
-	 * Make sure we can deassign from the pt_domain itself.
-	 */
-	if (iommu_pass_through &&
-	    (dev_data->domain == NULL && domain != pt_domain))
-		__attach_device(dev, pt_domain);
-}
-
-/*
- * Removes a device from a protection domain (with devtable_lock held)
- */
-static void detach_device(struct device *dev)
-{
-	struct pci_dev *pdev = to_pci_dev(dev);
-	unsigned long flags;
-
-	/* lock device table */
-	write_lock_irqsave(&amd_iommu_devtable_lock, flags);
-	__detach_device(dev);
-	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-
-	if (amd_iommu_iotlb_sup && pci_ats_enabled(pdev))
-		pci_disable_ats(pdev);
-}
-
-/*
- * Find out the protection domain structure for a given PCI device. This
- * will give us the pointer to the page table root for example.
- */
-static struct protection_domain *domain_for_device(struct device *dev)
-{
-	struct protection_domain *dom;
-	struct iommu_dev_data *dev_data, *alias_data;
-	unsigned long flags;
-	u16 devid;
-
-	devid      = get_device_id(dev);
-	dev_data   = get_dev_data(dev);
-	alias_data = get_dev_data(dev_data->alias);
-	if (!alias_data)
-		return NULL;
-
-	read_lock_irqsave(&amd_iommu_devtable_lock, flags);
-	dom = dev_data->domain;
-	if (dom == NULL &&
-	    alias_data->domain != NULL) {
-		__attach_device(dev, alias_data->domain);
-		dom = alias_data->domain;
-	}
-
-	read_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-
-	return dom;
-}
-
-static int device_change_notifier(struct notifier_block *nb,
-				  unsigned long action, void *data)
-{
-	struct device *dev = data;
-	u16 devid;
-	struct protection_domain *domain;
-	struct dma_ops_domain *dma_domain;
-	struct amd_iommu *iommu;
-	unsigned long flags;
-
-	if (!check_device(dev))
-		return 0;
-
-	devid  = get_device_id(dev);
-	iommu  = amd_iommu_rlookup_table[devid];
-
-	switch (action) {
-	case BUS_NOTIFY_UNBOUND_DRIVER:
-
-		domain = domain_for_device(dev);
-
-		if (!domain)
-			goto out;
-		if (iommu_pass_through)
-			break;
-		detach_device(dev);
-		break;
-	case BUS_NOTIFY_ADD_DEVICE:
-
-		iommu_init_device(dev);
-
-		domain = domain_for_device(dev);
-
-		/* allocate a protection domain if a device is added */
-		dma_domain = find_protection_domain(devid);
-		if (dma_domain)
-			goto out;
-		dma_domain = dma_ops_domain_alloc();
-		if (!dma_domain)
-			goto out;
-		dma_domain->target_dev = devid;
-
-		spin_lock_irqsave(&iommu_pd_list_lock, flags);
-		list_add_tail(&dma_domain->list, &iommu_pd_list);
-		spin_unlock_irqrestore(&iommu_pd_list_lock, flags);
-
-		break;
-	case BUS_NOTIFY_DEL_DEVICE:
-
-		iommu_uninit_device(dev);
-
-	default:
-		goto out;
-	}
-
-	device_flush_dte(dev);
-	iommu_completion_wait(iommu);
-
-out:
-	return 0;
-}
-
-static struct notifier_block device_nb = {
-	.notifier_call = device_change_notifier,
-};
-
-void amd_iommu_init_notifier(void)
-{
-	bus_register_notifier(&pci_bus_type, &device_nb);
-}
-
-/*****************************************************************************
- *
- * The next functions belong to the dma_ops mapping/unmapping code.
- *
- *****************************************************************************/
-
-/*
- * In the dma_ops path we only have the struct device. This function
- * finds the corresponding IOMMU, the protection domain and the
- * requestor id for a given device.
- * If the device is not yet associated with a domain this is also done
- * in this function.
- */
-static struct protection_domain *get_domain(struct device *dev)
-{
-	struct protection_domain *domain;
-	struct dma_ops_domain *dma_dom;
-	u16 devid = get_device_id(dev);
-
-	if (!check_device(dev))
-		return ERR_PTR(-EINVAL);
-
-	domain = domain_for_device(dev);
-	if (domain != NULL && !dma_ops_domain(domain))
-		return ERR_PTR(-EBUSY);
-
-	if (domain != NULL)
-		return domain;
-
-	/* Device not bount yet - bind it */
-	dma_dom = find_protection_domain(devid);
-	if (!dma_dom)
-		dma_dom = amd_iommu_rlookup_table[devid]->default_dom;
-	attach_device(dev, &dma_dom->domain);
-	DUMP_printk("Using protection domain %d for device %s\n",
-		    dma_dom->domain.id, dev_name(dev));
-
-	return &dma_dom->domain;
-}
-
-static void update_device_table(struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data;
-
-	list_for_each_entry(dev_data, &domain->dev_list, list) {
-		struct pci_dev *pdev = to_pci_dev(dev_data->dev);
-		u16 devid = get_device_id(dev_data->dev);
-		set_dte_entry(devid, domain, pci_ats_enabled(pdev));
-	}
-}
-
-static void update_domain(struct protection_domain *domain)
-{
-	if (!domain->updated)
-		return;
-
-	update_device_table(domain);
-
-	domain_flush_devices(domain);
-	domain_flush_tlb_pde(domain);
-
-	domain->updated = false;
-}
-
-/*
- * This function fetches the PTE for a given address in the aperture
- */
-static u64* dma_ops_get_pte(struct dma_ops_domain *dom,
-			    unsigned long address)
-{
-	struct aperture_range *aperture;
-	u64 *pte, *pte_page;
-
-	aperture = dom->aperture[APERTURE_RANGE_INDEX(address)];
-	if (!aperture)
-		return NULL;
-
-	pte = aperture->pte_pages[APERTURE_PAGE_INDEX(address)];
-	if (!pte) {
-		pte = alloc_pte(&dom->domain, address, PAGE_SIZE, &pte_page,
-				GFP_ATOMIC);
-		aperture->pte_pages[APERTURE_PAGE_INDEX(address)] = pte_page;
-	} else
-		pte += PM_LEVEL_INDEX(0, address);
-
-	update_domain(&dom->domain);
-
-	return pte;
-}
-
-/*
- * This is the generic map function. It maps one 4kb page at paddr to
- * the given address in the DMA address space for the domain.
- */
-static dma_addr_t dma_ops_domain_map(struct dma_ops_domain *dom,
-				     unsigned long address,
-				     phys_addr_t paddr,
-				     int direction)
-{
-	u64 *pte, __pte;
-
-	WARN_ON(address > dom->aperture_size);
-
-	paddr &= PAGE_MASK;
-
-	pte  = dma_ops_get_pte(dom, address);
-	if (!pte)
-		return DMA_ERROR_CODE;
-
-	__pte = paddr | IOMMU_PTE_P | IOMMU_PTE_FC;
-
-	if (direction == DMA_TO_DEVICE)
-		__pte |= IOMMU_PTE_IR;
-	else if (direction == DMA_FROM_DEVICE)
-		__pte |= IOMMU_PTE_IW;
-	else if (direction == DMA_BIDIRECTIONAL)
-		__pte |= IOMMU_PTE_IR | IOMMU_PTE_IW;
-
-	WARN_ON(*pte);
-
-	*pte = __pte;
-
-	return (dma_addr_t)address;
-}
-
-/*
- * The generic unmapping function for on page in the DMA address space.
- */
-static void dma_ops_domain_unmap(struct dma_ops_domain *dom,
-				 unsigned long address)
-{
-	struct aperture_range *aperture;
-	u64 *pte;
-
-	if (address >= dom->aperture_size)
-		return;
-
-	aperture = dom->aperture[APERTURE_RANGE_INDEX(address)];
-	if (!aperture)
-		return;
-
-	pte  = aperture->pte_pages[APERTURE_PAGE_INDEX(address)];
-	if (!pte)
-		return;
-
-	pte += PM_LEVEL_INDEX(0, address);
-
-	WARN_ON(!*pte);
-
-	*pte = 0ULL;
-}
-
-/*
- * This function contains common code for mapping of a physically
- * contiguous memory region into DMA address space. It is used by all
- * mapping functions provided with this IOMMU driver.
- * Must be called with the domain lock held.
- */
-static dma_addr_t __map_single(struct device *dev,
-			       struct dma_ops_domain *dma_dom,
-			       phys_addr_t paddr,
-			       size_t size,
-			       int dir,
-			       bool align,
-			       u64 dma_mask)
-{
-	dma_addr_t offset = paddr & ~PAGE_MASK;
-	dma_addr_t address, start, ret;
-	unsigned int pages;
-	unsigned long align_mask = 0;
-	int i;
-
-	pages = iommu_num_pages(paddr, size, PAGE_SIZE);
-	paddr &= PAGE_MASK;
-
-	INC_STATS_COUNTER(total_map_requests);
-
-	if (pages > 1)
-		INC_STATS_COUNTER(cross_page);
-
-	if (align)
-		align_mask = (1UL << get_order(size)) - 1;
-
-retry:
-	address = dma_ops_alloc_addresses(dev, dma_dom, pages, align_mask,
-					  dma_mask);
-	if (unlikely(address == DMA_ERROR_CODE)) {
-		/*
-		 * setting next_address here will let the address
-		 * allocator only scan the new allocated range in the
-		 * first run. This is a small optimization.
-		 */
-		dma_dom->next_address = dma_dom->aperture_size;
-
-		if (alloc_new_range(dma_dom, false, GFP_ATOMIC))
-			goto out;
-
-		/*
-		 * aperture was successfully enlarged by 128 MB, try
-		 * allocation again
-		 */
-		goto retry;
-	}
-
-	start = address;
-	for (i = 0; i < pages; ++i) {
-		ret = dma_ops_domain_map(dma_dom, start, paddr, dir);
-		if (ret == DMA_ERROR_CODE)
-			goto out_unmap;
-
-		paddr += PAGE_SIZE;
-		start += PAGE_SIZE;
-	}
-	address += offset;
-
-	ADD_STATS_COUNTER(alloced_io_mem, size);
-
-	if (unlikely(dma_dom->need_flush && !amd_iommu_unmap_flush)) {
-		domain_flush_tlb(&dma_dom->domain);
-		dma_dom->need_flush = false;
-	} else if (unlikely(amd_iommu_np_cache))
-		domain_flush_pages(&dma_dom->domain, address, size);
-
-out:
-	return address;
-
-out_unmap:
-
-	for (--i; i >= 0; --i) {
-		start -= PAGE_SIZE;
-		dma_ops_domain_unmap(dma_dom, start);
-	}
-
-	dma_ops_free_addresses(dma_dom, address, pages);
-
-	return DMA_ERROR_CODE;
-}
-
-/*
- * Does the reverse of the __map_single function. Must be called with
- * the domain lock held too
- */
-static void __unmap_single(struct dma_ops_domain *dma_dom,
-			   dma_addr_t dma_addr,
-			   size_t size,
-			   int dir)
-{
-	dma_addr_t flush_addr;
-	dma_addr_t i, start;
-	unsigned int pages;
-
-	if ((dma_addr == DMA_ERROR_CODE) ||
-	    (dma_addr + size > dma_dom->aperture_size))
-		return;
-
-	flush_addr = dma_addr;
-	pages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
-	dma_addr &= PAGE_MASK;
-	start = dma_addr;
-
-	for (i = 0; i < pages; ++i) {
-		dma_ops_domain_unmap(dma_dom, start);
-		start += PAGE_SIZE;
-	}
-
-	SUB_STATS_COUNTER(alloced_io_mem, size);
-
-	dma_ops_free_addresses(dma_dom, dma_addr, pages);
-
-	if (amd_iommu_unmap_flush || dma_dom->need_flush) {
-		domain_flush_pages(&dma_dom->domain, flush_addr, size);
-		dma_dom->need_flush = false;
-	}
-}
-
-/*
- * The exported map_single function for dma_ops.
- */
-static dma_addr_t map_page(struct device *dev, struct page *page,
-			   unsigned long offset, size_t size,
-			   enum dma_data_direction dir,
-			   struct dma_attrs *attrs)
-{
-	unsigned long flags;
-	struct protection_domain *domain;
-	dma_addr_t addr;
-	u64 dma_mask;
-	phys_addr_t paddr = page_to_phys(page) + offset;
-
-	INC_STATS_COUNTER(cnt_map_single);
-
-	domain = get_domain(dev);
-	if (PTR_ERR(domain) == -EINVAL)
-		return (dma_addr_t)paddr;
-	else if (IS_ERR(domain))
-		return DMA_ERROR_CODE;
-
-	dma_mask = *dev->dma_mask;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	addr = __map_single(dev, domain->priv, paddr, size, dir, false,
-			    dma_mask);
-	if (addr == DMA_ERROR_CODE)
-		goto out;
-
-	domain_flush_complete(domain);
-
-out:
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	return addr;
-}
-
-/*
- * The exported unmap_single function for dma_ops.
- */
-static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
-		       enum dma_data_direction dir, struct dma_attrs *attrs)
-{
-	unsigned long flags;
-	struct protection_domain *domain;
-
-	INC_STATS_COUNTER(cnt_unmap_single);
-
-	domain = get_domain(dev);
-	if (IS_ERR(domain))
-		return;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	__unmap_single(domain->priv, dma_addr, size, dir);
-
-	domain_flush_complete(domain);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-}
-
-/*
- * This is a special map_sg function which is used if we should map a
- * device which is not handled by an AMD IOMMU in the system.
- */
-static int map_sg_no_iommu(struct device *dev, struct scatterlist *sglist,
-			   int nelems, int dir)
-{
-	struct scatterlist *s;
-	int i;
-
-	for_each_sg(sglist, s, nelems, i) {
-		s->dma_address = (dma_addr_t)sg_phys(s);
-		s->dma_length  = s->length;
-	}
-
-	return nelems;
-}
-
-/*
- * The exported map_sg function for dma_ops (handles scatter-gather
- * lists).
- */
-static int map_sg(struct device *dev, struct scatterlist *sglist,
-		  int nelems, enum dma_data_direction dir,
-		  struct dma_attrs *attrs)
-{
-	unsigned long flags;
-	struct protection_domain *domain;
-	int i;
-	struct scatterlist *s;
-	phys_addr_t paddr;
-	int mapped_elems = 0;
-	u64 dma_mask;
-
-	INC_STATS_COUNTER(cnt_map_sg);
-
-	domain = get_domain(dev);
-	if (PTR_ERR(domain) == -EINVAL)
-		return map_sg_no_iommu(dev, sglist, nelems, dir);
-	else if (IS_ERR(domain))
-		return 0;
-
-	dma_mask = *dev->dma_mask;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	for_each_sg(sglist, s, nelems, i) {
-		paddr = sg_phys(s);
-
-		s->dma_address = __map_single(dev, domain->priv,
-					      paddr, s->length, dir, false,
-					      dma_mask);
-
-		if (s->dma_address) {
-			s->dma_length = s->length;
-			mapped_elems++;
-		} else
-			goto unmap;
-	}
-
-	domain_flush_complete(domain);
-
-out:
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	return mapped_elems;
-unmap:
-	for_each_sg(sglist, s, mapped_elems, i) {
-		if (s->dma_address)
-			__unmap_single(domain->priv, s->dma_address,
-				       s->dma_length, dir);
-		s->dma_address = s->dma_length = 0;
-	}
-
-	mapped_elems = 0;
-
-	goto out;
-}
-
-/*
- * The exported map_sg function for dma_ops (handles scatter-gather
- * lists).
- */
-static void unmap_sg(struct device *dev, struct scatterlist *sglist,
-		     int nelems, enum dma_data_direction dir,
-		     struct dma_attrs *attrs)
-{
-	unsigned long flags;
-	struct protection_domain *domain;
-	struct scatterlist *s;
-	int i;
-
-	INC_STATS_COUNTER(cnt_unmap_sg);
-
-	domain = get_domain(dev);
-	if (IS_ERR(domain))
-		return;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	for_each_sg(sglist, s, nelems, i) {
-		__unmap_single(domain->priv, s->dma_address,
-			       s->dma_length, dir);
-		s->dma_address = s->dma_length = 0;
-	}
-
-	domain_flush_complete(domain);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-}
-
-/*
- * The exported alloc_coherent function for dma_ops.
- */
-static void *alloc_coherent(struct device *dev, size_t size,
-			    dma_addr_t *dma_addr, gfp_t flag)
-{
-	unsigned long flags;
-	void *virt_addr;
-	struct protection_domain *domain;
-	phys_addr_t paddr;
-	u64 dma_mask = dev->coherent_dma_mask;
-
-	INC_STATS_COUNTER(cnt_alloc_coherent);
-
-	domain = get_domain(dev);
-	if (PTR_ERR(domain) == -EINVAL) {
-		virt_addr = (void *)__get_free_pages(flag, get_order(size));
-		*dma_addr = __pa(virt_addr);
-		return virt_addr;
-	} else if (IS_ERR(domain))
-		return NULL;
-
-	dma_mask  = dev->coherent_dma_mask;
-	flag     &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-	flag     |= __GFP_ZERO;
-
-	virt_addr = (void *)__get_free_pages(flag, get_order(size));
-	if (!virt_addr)
-		return NULL;
-
-	paddr = virt_to_phys(virt_addr);
-
-	if (!dma_mask)
-		dma_mask = *dev->dma_mask;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	*dma_addr = __map_single(dev, domain->priv, paddr,
-				 size, DMA_BIDIRECTIONAL, true, dma_mask);
-
-	if (*dma_addr == DMA_ERROR_CODE) {
-		spin_unlock_irqrestore(&domain->lock, flags);
-		goto out_free;
-	}
-
-	domain_flush_complete(domain);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-	return virt_addr;
-
-out_free:
-
-	free_pages((unsigned long)virt_addr, get_order(size));
-
-	return NULL;
-}
-
-/*
- * The exported free_coherent function for dma_ops.
- */
-static void free_coherent(struct device *dev, size_t size,
-			  void *virt_addr, dma_addr_t dma_addr)
-{
-	unsigned long flags;
-	struct protection_domain *domain;
-
-	INC_STATS_COUNTER(cnt_free_coherent);
-
-	domain = get_domain(dev);
-	if (IS_ERR(domain))
-		goto free_mem;
-
-	spin_lock_irqsave(&domain->lock, flags);
-
-	__unmap_single(domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
-
-	domain_flush_complete(domain);
-
-	spin_unlock_irqrestore(&domain->lock, flags);
-
-free_mem:
-	free_pages((unsigned long)virt_addr, get_order(size));
-}
-
-/*
- * This function is called by the DMA layer to find out if we can handle a
- * particular device. It is part of the dma_ops.
- */
-static int amd_iommu_dma_supported(struct device *dev, u64 mask)
-{
-	return check_device(dev);
-}
-
-/*
- * The function for pre-allocating protection domains.
- *
- * If the driver core informs the DMA layer if a driver grabs a device
- * we don't need to preallocate the protection domains anymore.
- * For now we have to.
- */
-static void prealloc_protection_domains(void)
-{
-	struct pci_dev *dev = NULL;
-	struct dma_ops_domain *dma_dom;
-	u16 devid;
-
-	for_each_pci_dev(dev) {
-
-		/* Do we handle this device? */
-		if (!check_device(&dev->dev))
-			continue;
-
-		/* Is there already any domain for it? */
-		if (domain_for_device(&dev->dev))
-			continue;
-
-		devid = get_device_id(&dev->dev);
-
-		dma_dom = dma_ops_domain_alloc();
-		if (!dma_dom)
-			continue;
-		init_unity_mappings_for_device(dma_dom, devid);
-		dma_dom->target_dev = devid;
-
-		attach_device(&dev->dev, &dma_dom->domain);
-
-		list_add_tail(&dma_dom->list, &iommu_pd_list);
-	}
-}
-
-static struct dma_map_ops amd_iommu_dma_ops = {
-	.alloc_coherent = alloc_coherent,
-	.free_coherent = free_coherent,
-	.map_page = map_page,
-	.unmap_page = unmap_page,
-	.map_sg = map_sg,
-	.unmap_sg = unmap_sg,
-	.dma_supported = amd_iommu_dma_supported,
-};
-
-static unsigned device_dma_ops_init(void)
-{
-	struct pci_dev *pdev = NULL;
-	unsigned unhandled = 0;
-
-	for_each_pci_dev(pdev) {
-		if (!check_device(&pdev->dev)) {
-			unhandled += 1;
-			continue;
-		}
-
-		pdev->dev.archdata.dma_ops = &amd_iommu_dma_ops;
-	}
-
-	return unhandled;
-}
-
-/*
- * The function which clues the AMD IOMMU driver into dma_ops.
- */
-
-void __init amd_iommu_init_api(void)
-{
-	register_iommu(&amd_iommu_ops);
-}
-
-int __init amd_iommu_init_dma_ops(void)
-{
-	struct amd_iommu *iommu;
-	int ret, unhandled;
-
-	/*
-	 * first allocate a default protection domain for every IOMMU we
-	 * found in the system. Devices not assigned to any other
-	 * protection domain will be assigned to the default one.
-	 */
-	for_each_iommu(iommu) {
-		iommu->default_dom = dma_ops_domain_alloc();
-		if (iommu->default_dom == NULL)
-			return -ENOMEM;
-		iommu->default_dom->domain.flags |= PD_DEFAULT_MASK;
-		ret = iommu_init_unity_mappings(iommu);
-		if (ret)
-			goto free_domains;
-	}
-
-	/*
-	 * Pre-allocate the protection domains for each device.
-	 */
-	prealloc_protection_domains();
-
-	iommu_detected = 1;
-	swiotlb = 0;
-
-	/* Make the driver finally visible to the drivers */
-	unhandled = device_dma_ops_init();
-	if (unhandled && max_pfn > MAX_DMA32_PFN) {
-		/* There are unhandled devices - initialize swiotlb for them */
-		swiotlb = 1;
-	}
-
-	amd_iommu_stats_init();
-
-	return 0;
-
-free_domains:
-
-	for_each_iommu(iommu) {
-		if (iommu->default_dom)
-			dma_ops_domain_free(iommu->default_dom);
-	}
-
-	return ret;
-}
-
-/*****************************************************************************
- *
- * The following functions belong to the exported interface of AMD IOMMU
- *
- * This interface allows access to lower level functions of the IOMMU
- * like protection domain handling and assignement of devices to domains
- * which is not possible with the dma_ops interface.
- *
- *****************************************************************************/
-
-static void cleanup_domain(struct protection_domain *domain)
-{
-	struct iommu_dev_data *dev_data, *next;
-	unsigned long flags;
-
-	write_lock_irqsave(&amd_iommu_devtable_lock, flags);
-
-	list_for_each_entry_safe(dev_data, next, &domain->dev_list, list) {
-		struct device *dev = dev_data->dev;
-
-		__detach_device(dev);
-		atomic_set(&dev_data->bind, 0);
-	}
-
-	write_unlock_irqrestore(&amd_iommu_devtable_lock, flags);
-}
-
-static void protection_domain_free(struct protection_domain *domain)
-{
-	if (!domain)
-		return;
-
-	del_domain_from_list(domain);
-
-	if (domain->id)
-		domain_id_free(domain->id);
-
-	kfree(domain);
-}
-
-static struct protection_domain *protection_domain_alloc(void)
-{
-	struct protection_domain *domain;
-
-	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
-	if (!domain)
-		return NULL;
-
-	spin_lock_init(&domain->lock);
-	mutex_init(&domain->api_lock);
-	domain->id = domain_id_alloc();
-	if (!domain->id)
-		goto out_err;
-	INIT_LIST_HEAD(&domain->dev_list);
-
-	add_domain_to_list(domain);
-
-	return domain;
-
-out_err:
-	kfree(domain);
-
-	return NULL;
-}
-
-static int amd_iommu_domain_init(struct iommu_domain *dom)
-{
-	struct protection_domain *domain;
-
-	domain = protection_domain_alloc();
-	if (!domain)
-		goto out_free;
-
-	domain->mode    = PAGE_MODE_3_LEVEL;
-	domain->pt_root = (void *)get_zeroed_page(GFP_KERNEL);
-	if (!domain->pt_root)
-		goto out_free;
-
-	dom->priv = domain;
-
-	return 0;
-
-out_free:
-	protection_domain_free(domain);
-
-	return -ENOMEM;
-}
-
-static void amd_iommu_domain_destroy(struct iommu_domain *dom)
-{
-	struct protection_domain *domain = dom->priv;
-
-	if (!domain)
-		return;
-
-	if (domain->dev_cnt > 0)
-		cleanup_domain(domain);
-
-	BUG_ON(domain->dev_cnt != 0);
-
-	free_pagetable(domain);
-
-	protection_domain_free(domain);
-
-	dom->priv = NULL;
-}
-
-static void amd_iommu_detach_device(struct iommu_domain *dom,
-				    struct device *dev)
-{
-	struct iommu_dev_data *dev_data = dev->archdata.iommu;
-	struct amd_iommu *iommu;
-	u16 devid;
-
-	if (!check_device(dev))
-		return;
-
-	devid = get_device_id(dev);
-
-	if (dev_data->domain != NULL)
-		detach_device(dev);
-
-	iommu = amd_iommu_rlookup_table[devid];
-	if (!iommu)
-		return;
-
-	device_flush_dte(dev);
-	iommu_completion_wait(iommu);
-}
-
-static int amd_iommu_attach_device(struct iommu_domain *dom,
-				   struct device *dev)
-{
-	struct protection_domain *domain = dom->priv;
-	struct iommu_dev_data *dev_data;
-	struct amd_iommu *iommu;
-	int ret;
-	u16 devid;
-
-	if (!check_device(dev))
-		return -EINVAL;
-
-	dev_data = dev->archdata.iommu;
-
-	devid = get_device_id(dev);
-
-	iommu = amd_iommu_rlookup_table[devid];
-	if (!iommu)
-		return -EINVAL;
-
-	if (dev_data->domain)
-		detach_device(dev);
-
-	ret = attach_device(dev, domain);
-
-	iommu_completion_wait(iommu);
-
-	return ret;
-}
-
-static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
-			 phys_addr_t paddr, int gfp_order, int iommu_prot)
-{
-	unsigned long page_size = 0x1000UL << gfp_order;
-	struct protection_domain *domain = dom->priv;
-	int prot = 0;
-	int ret;
-
-	if (iommu_prot & IOMMU_READ)
-		prot |= IOMMU_PROT_IR;
-	if (iommu_prot & IOMMU_WRITE)
-		prot |= IOMMU_PROT_IW;
-
-	mutex_lock(&domain->api_lock);
-	ret = iommu_map_page(domain, iova, paddr, prot, page_size);
-	mutex_unlock(&domain->api_lock);
-
-	return ret;
-}
-
-static int amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
-			   int gfp_order)
-{
-	struct protection_domain *domain = dom->priv;
-	unsigned long page_size, unmap_size;
-
-	page_size  = 0x1000UL << gfp_order;
-
-	mutex_lock(&domain->api_lock);
-	unmap_size = iommu_unmap_page(domain, iova, page_size);
-	mutex_unlock(&domain->api_lock);
-
-	domain_flush_tlb_pde(domain);
-
-	return get_order(unmap_size);
-}
-
-static phys_addr_t amd_iommu_iova_to_phys(struct iommu_domain *dom,
-					  unsigned long iova)
-{
-	struct protection_domain *domain = dom->priv;
-	unsigned long offset_mask;
-	phys_addr_t paddr;
-	u64 *pte, __pte;
-
-	pte = fetch_pte(domain, iova);
-
-	if (!pte || !IOMMU_PTE_PRESENT(*pte))
-		return 0;
-
-	if (PM_PTE_LEVEL(*pte) == 0)
-		offset_mask = PAGE_SIZE - 1;
-	else
-		offset_mask = PTE_PAGE_SIZE(*pte) - 1;
-
-	__pte = *pte & PM_ADDR_MASK;
-	paddr = (__pte & ~offset_mask) | (iova & offset_mask);
-
-	return paddr;
-}
-
-static int amd_iommu_domain_has_cap(struct iommu_domain *domain,
-				    unsigned long cap)
-{
-	switch (cap) {
-	case IOMMU_CAP_CACHE_COHERENCY:
-		return 1;
-	}
-
-	return 0;
-}
-
-static struct iommu_ops amd_iommu_ops = {
-	.domain_init = amd_iommu_domain_init,
-	.domain_destroy = amd_iommu_domain_destroy,
-	.attach_dev = amd_iommu_attach_device,
-	.detach_dev = amd_iommu_detach_device,
-	.map = amd_iommu_map,
-	.unmap = amd_iommu_unmap,
-	.iova_to_phys = amd_iommu_iova_to_phys,
-	.domain_has_cap = amd_iommu_domain_has_cap,
-};
-
-/*****************************************************************************
- *
- * The next functions do a basic initialization of IOMMU for pass through
- * mode
- *
- * In passthrough mode the IOMMU is initialized and enabled but not used for
- * DMA-API translation.
- *
- *****************************************************************************/
-
-int __init amd_iommu_init_passthrough(void)
-{
-	struct amd_iommu *iommu;
-	struct pci_dev *dev = NULL;
-	u16 devid;
-
-	/* allocate passthrough domain */
-	pt_domain = protection_domain_alloc();
-	if (!pt_domain)
-		return -ENOMEM;
-
-	pt_domain->mode |= PAGE_MODE_NONE;
-
-	for_each_pci_dev(dev) {
-		if (!check_device(&dev->dev))
-			continue;
-
-		devid = get_device_id(&dev->dev);
-
-		iommu = amd_iommu_rlookup_table[devid];
-		if (!iommu)
-			continue;
-
-		attach_device(&dev->dev, pt_domain);
-	}
-
-	pr_info("AMD-Vi: Initialized for Passthrough Mode\n");
-
-	return 0;
-}