Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8c15c59..d658c7c 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1,19 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
  * Author: Joerg Roedel <jroedel@suse.de>
- *
- * 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
  */
 
 #define pr_fmt(fmt)    "iommu: " fmt
@@ -22,7 +10,8 @@
 #include <linux/kernel.h>
 #include <linux/bug.h>
 #include <linux/types.h>
-#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
 #include <linux/iommu.h>
@@ -32,19 +21,15 @@
 #include <linux/pci.h>
 #include <linux/bitops.h>
 #include <linux/property.h>
+#include <linux/fsl/mc.h>
 #include <trace/events/iommu.h>
 
 static struct kset *iommu_group_kset;
 static DEFINE_IDA(iommu_group_ida);
-#ifdef CONFIG_IOMMU_DEFAULT_PASSTHROUGH
-static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY;
-#else
-static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA;
-#endif
 
-struct iommu_callback_data {
-	const struct iommu_ops *ops;
-};
+static unsigned int iommu_def_domain_type __read_mostly;
+static bool iommu_dma_strict __read_mostly = true;
+static u32 iommu_cmd_line __read_mostly;
 
 struct iommu_group {
 	struct kobject kobj;
@@ -74,12 +59,25 @@
 };
 
 static const char * const iommu_group_resv_type_string[] = {
-	[IOMMU_RESV_DIRECT]	= "direct",
-	[IOMMU_RESV_RESERVED]	= "reserved",
-	[IOMMU_RESV_MSI]	= "msi",
-	[IOMMU_RESV_SW_MSI]	= "msi",
+	[IOMMU_RESV_DIRECT]			= "direct",
+	[IOMMU_RESV_DIRECT_RELAXABLE]		= "direct-relaxable",
+	[IOMMU_RESV_RESERVED]			= "reserved",
+	[IOMMU_RESV_MSI]			= "msi",
+	[IOMMU_RESV_SW_MSI]			= "msi",
 };
 
+#define IOMMU_CMD_LINE_DMA_API		BIT(0)
+
+static void iommu_set_cmd_line_dma_api(void)
+{
+	iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API;
+}
+
+static bool iommu_cmd_line_dma_api(void)
+{
+	return !!(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API);
+}
+
 #define IOMMU_GROUP_ATTR(_name, _mode, _show, _store)		\
 struct iommu_group_attribute iommu_group_attr_##_name =		\
 	__ATTR(_name, _mode, _show, _store)
@@ -92,12 +90,55 @@
 static LIST_HEAD(iommu_device_list);
 static DEFINE_SPINLOCK(iommu_device_lock);
 
+/*
+ * Use a function instead of an array here because the domain-type is a
+ * bit-field, so an array would waste memory.
+ */
+static const char *iommu_domain_type_str(unsigned int t)
+{
+	switch (t) {
+	case IOMMU_DOMAIN_BLOCKED:
+		return "Blocked";
+	case IOMMU_DOMAIN_IDENTITY:
+		return "Passthrough";
+	case IOMMU_DOMAIN_UNMANAGED:
+		return "Unmanaged";
+	case IOMMU_DOMAIN_DMA:
+		return "Translated";
+	default:
+		return "Unknown";
+	}
+}
+
+static int __init iommu_subsys_init(void)
+{
+	bool cmd_line = iommu_cmd_line_dma_api();
+
+	if (!cmd_line) {
+		if (IS_ENABLED(CONFIG_IOMMU_DEFAULT_PASSTHROUGH))
+			iommu_set_default_passthrough(false);
+		else
+			iommu_set_default_translated(false);
+
+		if (iommu_default_passthrough() && mem_encrypt_active()) {
+			pr_info("Memory encryption detected - Disabling default IOMMU Passthrough\n");
+			iommu_set_default_translated(false);
+		}
+	}
+
+	pr_info("Default domain type: %s %s\n",
+		iommu_domain_type_str(iommu_def_domain_type),
+		cmd_line ? "(set via kernel command line)" : "");
+
+	return 0;
+}
+subsys_initcall(iommu_subsys_init);
+
 int iommu_device_register(struct iommu_device *iommu)
 {
 	spin_lock(&iommu_device_lock);
 	list_add_tail(&iommu->list, &iommu_device_list);
 	spin_unlock(&iommu_device_lock);
-
 	return 0;
 }
 
@@ -108,6 +149,57 @@
 	spin_unlock(&iommu_device_lock);
 }
 
+static struct iommu_param *iommu_get_dev_param(struct device *dev)
+{
+	struct iommu_param *param = dev->iommu_param;
+
+	if (param)
+		return param;
+
+	param = kzalloc(sizeof(*param), GFP_KERNEL);
+	if (!param)
+		return NULL;
+
+	mutex_init(&param->lock);
+	dev->iommu_param = param;
+	return param;
+}
+
+static void iommu_free_dev_param(struct device *dev)
+{
+	kfree(dev->iommu_param);
+	dev->iommu_param = NULL;
+}
+
+int iommu_probe_device(struct device *dev)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+	int ret;
+
+	WARN_ON(dev->iommu_group);
+	if (!ops)
+		return -EINVAL;
+
+	if (!iommu_get_dev_param(dev))
+		return -ENOMEM;
+
+	ret = ops->add_device(dev);
+	if (ret)
+		iommu_free_dev_param(dev);
+
+	return ret;
+}
+
+void iommu_release_device(struct device *dev)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (dev->iommu_group)
+		ops->remove_device(dev);
+
+	iommu_free_dev_param(dev);
+}
+
 static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
 						 unsigned type);
 static int __iommu_attach_device(struct iommu_domain *domain,
@@ -126,11 +218,21 @@
 	if (ret)
 		return ret;
 
-	iommu_def_domain_type = pt ? IOMMU_DOMAIN_IDENTITY : IOMMU_DOMAIN_DMA;
+	if (pt)
+		iommu_set_default_passthrough(true);
+	else
+		iommu_set_default_translated(true);
+
 	return 0;
 }
 early_param("iommu.passthrough", iommu_set_def_domain_type);
 
+static int __init iommu_dma_setup(char *str)
+{
+	return kstrtobool(str, &iommu_dma_strict);
+}
+early_param("iommu.strict", iommu_dma_setup);
+
 static ssize_t iommu_group_attr_show(struct kobject *kobj,
 				     struct attribute *__attr, char *buf)
 {
@@ -184,58 +286,58 @@
  * @new: new region to insert
  * @regions: list of regions
  *
- * The new element is sorted by address with respect to the other
- * regions of the same type. In case it overlaps with another
- * region of the same type, regions are merged. In case it
- * overlaps with another region of different type, regions are
- * not merged.
+ * Elements are sorted by start address and overlapping segments
+ * of the same type are merged.
  */
-static int iommu_insert_resv_region(struct iommu_resv_region *new,
-				    struct list_head *regions)
+int iommu_insert_resv_region(struct iommu_resv_region *new,
+			     struct list_head *regions)
 {
-	struct iommu_resv_region *region;
-	phys_addr_t start = new->start;
-	phys_addr_t end = new->start + new->length - 1;
-	struct list_head *pos = regions->next;
+	struct iommu_resv_region *iter, *tmp, *nr, *top;
+	LIST_HEAD(stack);
 
-	while (pos != regions) {
-		struct iommu_resv_region *entry =
-			list_entry(pos, struct iommu_resv_region, list);
-		phys_addr_t a = entry->start;
-		phys_addr_t b = entry->start + entry->length - 1;
-		int type = entry->type;
-
-		if (end < a) {
-			goto insert;
-		} else if (start > b) {
-			pos = pos->next;
-		} else if ((start >= a) && (end <= b)) {
-			if (new->type == type)
-				goto done;
-			else
-				pos = pos->next;
-		} else {
-			if (new->type == type) {
-				phys_addr_t new_start = min(a, start);
-				phys_addr_t new_end = max(b, end);
-
-				list_del(&entry->list);
-				entry->start = new_start;
-				entry->length = new_end - new_start + 1;
-				iommu_insert_resv_region(entry, regions);
-			} else {
-				pos = pos->next;
-			}
-		}
-	}
-insert:
-	region = iommu_alloc_resv_region(new->start, new->length,
-					 new->prot, new->type);
-	if (!region)
+	nr = iommu_alloc_resv_region(new->start, new->length,
+				     new->prot, new->type);
+	if (!nr)
 		return -ENOMEM;
 
-	list_add_tail(&region->list, pos);
-done:
+	/* First add the new element based on start address sorting */
+	list_for_each_entry(iter, regions, list) {
+		if (nr->start < iter->start ||
+		    (nr->start == iter->start && nr->type <= iter->type))
+			break;
+	}
+	list_add_tail(&nr->list, &iter->list);
+
+	/* Merge overlapping segments of type nr->type in @regions, if any */
+	list_for_each_entry_safe(iter, tmp, regions, list) {
+		phys_addr_t top_end, iter_end = iter->start + iter->length - 1;
+
+		/* no merge needed on elements of different types than @nr */
+		if (iter->type != nr->type) {
+			list_move_tail(&iter->list, &stack);
+			continue;
+		}
+
+		/* look for the last stack element of same type as @iter */
+		list_for_each_entry_reverse(top, &stack, list)
+			if (top->type == iter->type)
+				goto check_overlap;
+
+		list_move_tail(&iter->list, &stack);
+		continue;
+
+check_overlap:
+		top_end = top->start + top->length - 1;
+
+		if (iter->start > top_end + 1) {
+			list_move_tail(&iter->list, &stack);
+		} else {
+			top->length = max(top_end, iter_end) - top->start + 1;
+			list_del(&iter->list);
+			kfree(iter);
+		}
+	}
+	list_splice(&stack, regions);
 	return 0;
 }
 
@@ -315,7 +417,7 @@
 			type = "unmanaged\n";
 			break;
 		case IOMMU_DOMAIN_DMA:
-			type = "DMA";
+			type = "DMA\n";
 			break;
 		}
 	}
@@ -547,7 +649,8 @@
 		start = ALIGN(entry->start, pg_size);
 		end   = ALIGN(entry->start + entry->length, pg_size);
 
-		if (entry->type != IOMMU_RESV_DIRECT)
+		if (entry->type != IOMMU_RESV_DIRECT &&
+		    entry->type != IOMMU_RESV_DIRECT_RELAXABLE)
 			continue;
 
 		for (addr = start; addr < end; addr += pg_size) {
@@ -638,7 +741,7 @@
 
 	trace_add_device_to_group(group->id, dev);
 
-	pr_info("Adding device %s to group %d\n", dev_name(dev), group->id);
+	dev_info(dev, "Adding to iommu group %d\n", group->id);
 
 	return 0;
 
@@ -654,7 +757,7 @@
 	sysfs_remove_link(&dev->kobj, "iommu_group");
 err_free_device:
 	kfree(device);
-	pr_err("Failed to add device %s to group %d: %d\n", dev_name(dev), group->id, ret);
+	dev_err(dev, "Failed to add to iommu group %d: %d\n", group->id, ret);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(iommu_group_add_device);
@@ -671,7 +774,7 @@
 	struct iommu_group *group = dev->iommu_group;
 	struct group_device *tmp_device, *device = NULL;
 
-	pr_info("Removing device %s from group %d\n", dev_name(dev), group->id);
+	dev_info(dev, "Removing from iommu group %d\n", group->id);
 
 	/* Pre-notify listeners that a device is being removed. */
 	blocking_notifier_call_chain(&group->notifier,
@@ -829,6 +932,206 @@
 EXPORT_SYMBOL_GPL(iommu_group_unregister_notifier);
 
 /**
+ * iommu_register_device_fault_handler() - Register a device fault handler
+ * @dev: the device
+ * @handler: the fault handler
+ * @data: private data passed as argument to the handler
+ *
+ * When an IOMMU fault event is received, this handler gets called with the
+ * fault event and data as argument. The handler should return 0 on success. If
+ * the fault is recoverable (IOMMU_FAULT_PAGE_REQ), the consumer should also
+ * complete the fault by calling iommu_page_response() with one of the following
+ * response code:
+ * - IOMMU_PAGE_RESP_SUCCESS: retry the translation
+ * - IOMMU_PAGE_RESP_INVALID: terminate the fault
+ * - IOMMU_PAGE_RESP_FAILURE: terminate the fault and stop reporting
+ *   page faults if possible.
+ *
+ * Return 0 if the fault handler was installed successfully, or an error.
+ */
+int iommu_register_device_fault_handler(struct device *dev,
+					iommu_dev_fault_handler_t handler,
+					void *data)
+{
+	struct iommu_param *param = dev->iommu_param;
+	int ret = 0;
+
+	if (!param)
+		return -EINVAL;
+
+	mutex_lock(&param->lock);
+	/* Only allow one fault handler registered for each device */
+	if (param->fault_param) {
+		ret = -EBUSY;
+		goto done_unlock;
+	}
+
+	get_device(dev);
+	param->fault_param = kzalloc(sizeof(*param->fault_param), GFP_KERNEL);
+	if (!param->fault_param) {
+		put_device(dev);
+		ret = -ENOMEM;
+		goto done_unlock;
+	}
+	param->fault_param->handler = handler;
+	param->fault_param->data = data;
+	mutex_init(&param->fault_param->lock);
+	INIT_LIST_HEAD(&param->fault_param->faults);
+
+done_unlock:
+	mutex_unlock(&param->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_register_device_fault_handler);
+
+/**
+ * iommu_unregister_device_fault_handler() - Unregister the device fault handler
+ * @dev: the device
+ *
+ * Remove the device fault handler installed with
+ * iommu_register_device_fault_handler().
+ *
+ * Return 0 on success, or an error.
+ */
+int iommu_unregister_device_fault_handler(struct device *dev)
+{
+	struct iommu_param *param = dev->iommu_param;
+	int ret = 0;
+
+	if (!param)
+		return -EINVAL;
+
+	mutex_lock(&param->lock);
+
+	if (!param->fault_param)
+		goto unlock;
+
+	/* we cannot unregister handler if there are pending faults */
+	if (!list_empty(&param->fault_param->faults)) {
+		ret = -EBUSY;
+		goto unlock;
+	}
+
+	kfree(param->fault_param);
+	param->fault_param = NULL;
+	put_device(dev);
+unlock:
+	mutex_unlock(&param->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_unregister_device_fault_handler);
+
+/**
+ * iommu_report_device_fault() - Report fault event to device driver
+ * @dev: the device
+ * @evt: fault event data
+ *
+ * Called by IOMMU drivers when a fault is detected, typically in a threaded IRQ
+ * handler. When this function fails and the fault is recoverable, it is the
+ * caller's responsibility to complete the fault.
+ *
+ * Return 0 on success, or an error.
+ */
+int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt)
+{
+	struct iommu_param *param = dev->iommu_param;
+	struct iommu_fault_event *evt_pending = NULL;
+	struct iommu_fault_param *fparam;
+	int ret = 0;
+
+	if (!param || !evt)
+		return -EINVAL;
+
+	/* we only report device fault if there is a handler registered */
+	mutex_lock(&param->lock);
+	fparam = param->fault_param;
+	if (!fparam || !fparam->handler) {
+		ret = -EINVAL;
+		goto done_unlock;
+	}
+
+	if (evt->fault.type == IOMMU_FAULT_PAGE_REQ &&
+	    (evt->fault.prm.flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE)) {
+		evt_pending = kmemdup(evt, sizeof(struct iommu_fault_event),
+				      GFP_KERNEL);
+		if (!evt_pending) {
+			ret = -ENOMEM;
+			goto done_unlock;
+		}
+		mutex_lock(&fparam->lock);
+		list_add_tail(&evt_pending->list, &fparam->faults);
+		mutex_unlock(&fparam->lock);
+	}
+
+	ret = fparam->handler(&evt->fault, fparam->data);
+	if (ret && evt_pending) {
+		mutex_lock(&fparam->lock);
+		list_del(&evt_pending->list);
+		mutex_unlock(&fparam->lock);
+		kfree(evt_pending);
+	}
+done_unlock:
+	mutex_unlock(&param->lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_report_device_fault);
+
+int iommu_page_response(struct device *dev,
+			struct iommu_page_response *msg)
+{
+	bool pasid_valid;
+	int ret = -EINVAL;
+	struct iommu_fault_event *evt;
+	struct iommu_fault_page_request *prm;
+	struct iommu_param *param = dev->iommu_param;
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+
+	if (!domain || !domain->ops->page_response)
+		return -ENODEV;
+
+	if (!param || !param->fault_param)
+		return -EINVAL;
+
+	if (msg->version != IOMMU_PAGE_RESP_VERSION_1 ||
+	    msg->flags & ~IOMMU_PAGE_RESP_PASID_VALID)
+		return -EINVAL;
+
+	/* Only send response if there is a fault report pending */
+	mutex_lock(&param->fault_param->lock);
+	if (list_empty(&param->fault_param->faults)) {
+		dev_warn_ratelimited(dev, "no pending PRQ, drop response\n");
+		goto done_unlock;
+	}
+	/*
+	 * Check if we have a matching page request pending to respond,
+	 * otherwise return -EINVAL
+	 */
+	list_for_each_entry(evt, &param->fault_param->faults, list) {
+		prm = &evt->fault.prm;
+		pasid_valid = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+
+		if ((pasid_valid && prm->pasid != msg->pasid) ||
+		    prm->grpid != msg->grpid)
+			continue;
+
+		/* Sanitize the reply */
+		msg->flags = pasid_valid ? IOMMU_PAGE_RESP_PASID_VALID : 0;
+
+		ret = domain->ops->page_response(dev, evt, msg);
+		list_del(&evt->list);
+		kfree(evt);
+		break;
+	}
+
+done_unlock:
+	mutex_unlock(&param->fault_param->lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_page_response);
+
+/**
  * iommu_group_id - Return ID for a group
  * @group: the group to ID
  *
@@ -1024,6 +1327,18 @@
 	return iommu_group_alloc();
 }
 
+/* Get the IOMMU group for device on fsl-mc bus */
+struct iommu_group *fsl_mc_device_group(struct device *dev)
+{
+	struct device *cont_dev = fsl_mc_cont_dev(dev);
+	struct iommu_group *group;
+
+	group = iommu_group_get(cont_dev);
+	if (!group)
+		group = iommu_group_alloc();
+	return group;
+}
+
 /**
  * iommu_group_get_for_dev - Find or create the IOMMU group for a device
  * @dev: target device
@@ -1063,15 +1378,24 @@
 
 		dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type);
 		if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) {
-			dev_warn(dev,
-				 "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA",
-				 iommu_def_domain_type);
 			dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA);
+			if (dom) {
+				dev_warn(dev,
+					 "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA",
+					 iommu_def_domain_type);
+			}
 		}
 
 		group->default_domain = dom;
 		if (!group->domain)
 			group->domain = dom;
+
+		if (dom && !iommu_dma_strict) {
+			int attr = 1;
+			iommu_domain_set_attr(dom,
+					      DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE,
+					      &attr);
+		}
 	}
 
 	ret = iommu_group_add_device(group, dev);
@@ -1090,16 +1414,7 @@
 
 static int add_iommu_group(struct device *dev, void *data)
 {
-	struct iommu_callback_data *cb = data;
-	const struct iommu_ops *ops = cb->ops;
-	int ret;
-
-	if (!ops->add_device)
-		return 0;
-
-	WARN_ON(dev->iommu_group);
-
-	ret = ops->add_device(dev);
+	int ret = iommu_probe_device(dev);
 
 	/*
 	 * We ignore -ENODEV errors for now, as they just mean that the
@@ -1114,11 +1429,7 @@
 
 static int remove_iommu_group(struct device *dev, void *data)
 {
-	struct iommu_callback_data *cb = data;
-	const struct iommu_ops *ops = cb->ops;
-
-	if (ops->remove_device && dev->iommu_group)
-		ops->remove_device(dev);
+	iommu_release_device(dev);
 
 	return 0;
 }
@@ -1126,27 +1437,22 @@
 static int iommu_bus_notifier(struct notifier_block *nb,
 			      unsigned long action, void *data)
 {
-	struct device *dev = data;
-	const struct iommu_ops *ops = dev->bus->iommu_ops;
-	struct iommu_group *group;
 	unsigned long group_action = 0;
+	struct device *dev = data;
+	struct iommu_group *group;
 
 	/*
 	 * ADD/DEL call into iommu driver ops if provided, which may
 	 * result in ADD/DEL notifiers to group->notifier
 	 */
 	if (action == BUS_NOTIFY_ADD_DEVICE) {
-		if (ops->add_device) {
-			int ret;
+		int ret;
 
-			ret = ops->add_device(dev);
-			return (ret) ? NOTIFY_DONE : NOTIFY_OK;
-		}
+		ret = iommu_probe_device(dev);
+		return (ret) ? NOTIFY_DONE : NOTIFY_OK;
 	} else if (action == BUS_NOTIFY_REMOVED_DEVICE) {
-		if (ops->remove_device && dev->iommu_group) {
-			ops->remove_device(dev);
-			return 0;
-		}
+		iommu_release_device(dev);
+		return NOTIFY_OK;
 	}
 
 	/*
@@ -1184,9 +1490,6 @@
 {
 	int err;
 	struct notifier_block *nb;
-	struct iommu_callback_data cb = {
-		.ops = ops,
-	};
 
 	nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL);
 	if (!nb)
@@ -1198,7 +1501,7 @@
 	if (err)
 		goto out_free;
 
-	err = bus_for_each_dev(bus, NULL, &cb, add_iommu_group);
+	err = bus_for_each_dev(bus, NULL, NULL, add_iommu_group);
 	if (err)
 		goto out_err;
 
@@ -1207,7 +1510,7 @@
 
 out_err:
 	/* Clean up */
-	bus_for_each_dev(bus, NULL, &cb, remove_iommu_group);
+	bus_for_each_dev(bus, NULL, NULL, remove_iommu_group);
 	bus_unregister_notifier(bus, nb);
 
 out_free:
@@ -1416,7 +1719,16 @@
 EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev);
 
 /*
- * IOMMU groups are really the natrual working unit of the IOMMU, but
+ * For IOMMU_DOMAIN_DMA implementations which already provide their own
+ * guarantees that the group and its default domain are valid and correct.
+ */
+struct iommu_domain *iommu_get_dma_domain(struct device *dev)
+{
+	return dev->iommu_group->default_domain;
+}
+
+/*
+ * IOMMU groups are really the natural working unit of the IOMMU, but
  * the IOMMU API works on domains and devices.  Bridge that gap by
  * iterating over the devices in a group.  Ideally we'd have a single
  * device which represents the requestor ID of the group, but we also
@@ -1545,13 +1857,14 @@
 int iommu_map(struct iommu_domain *domain, unsigned long iova,
 	      phys_addr_t paddr, size_t size, int prot)
 {
+	const struct iommu_ops *ops = domain->ops;
 	unsigned long orig_iova = iova;
 	unsigned int min_pagesz;
 	size_t orig_size = size;
 	phys_addr_t orig_paddr = paddr;
 	int ret = 0;
 
-	if (unlikely(domain->ops->map == NULL ||
+	if (unlikely(ops->map == NULL ||
 		     domain->pgsize_bitmap == 0UL))
 		return -ENODEV;
 
@@ -1580,7 +1893,7 @@
 		pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n",
 			 iova, &paddr, pgsize);
 
-		ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
+		ret = ops->map(domain, iova, paddr, pgsize, prot);
 		if (ret)
 			break;
 
@@ -1589,6 +1902,9 @@
 		size -= pgsize;
 	}
 
+	if (ops->iotlb_sync_map)
+		ops->iotlb_sync_map(domain);
+
 	/* unroll mapping in case something went wrong */
 	if (ret)
 		iommu_unmap(domain, orig_iova, orig_size - size);
@@ -1601,7 +1917,7 @@
 
 static size_t __iommu_unmap(struct iommu_domain *domain,
 			    unsigned long iova, size_t size,
-			    bool sync)
+			    struct iommu_iotlb_gather *iotlb_gather)
 {
 	const struct iommu_ops *ops = domain->ops;
 	size_t unmapped_page, unmapped = 0;
@@ -1638,13 +1954,10 @@
 	while (unmapped < size) {
 		size_t pgsize = iommu_pgsize(domain, iova, size - unmapped);
 
-		unmapped_page = ops->unmap(domain, iova, pgsize);
+		unmapped_page = ops->unmap(domain, iova, pgsize, iotlb_gather);
 		if (!unmapped_page)
 			break;
 
-		if (sync && ops->iotlb_range_add)
-			ops->iotlb_range_add(domain, iova, pgsize);
-
 		pr_debug("unmapped: iova 0x%lx size 0x%zx\n",
 			 iova, unmapped_page);
 
@@ -1652,9 +1965,6 @@
 		unmapped += unmapped_page;
 	}
 
-	if (sync && ops->iotlb_sync)
-		ops->iotlb_sync(domain);
-
 	trace_unmap(orig_iova, size, unmapped);
 	return unmapped;
 }
@@ -1662,47 +1972,54 @@
 size_t iommu_unmap(struct iommu_domain *domain,
 		   unsigned long iova, size_t size)
 {
-	return __iommu_unmap(domain, iova, size, true);
+	struct iommu_iotlb_gather iotlb_gather;
+	size_t ret;
+
+	iommu_iotlb_gather_init(&iotlb_gather);
+	ret = __iommu_unmap(domain, iova, size, &iotlb_gather);
+	iommu_tlb_sync(domain, &iotlb_gather);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(iommu_unmap);
 
 size_t iommu_unmap_fast(struct iommu_domain *domain,
-			unsigned long iova, size_t size)
+			unsigned long iova, size_t size,
+			struct iommu_iotlb_gather *iotlb_gather)
 {
-	return __iommu_unmap(domain, iova, size, false);
+	return __iommu_unmap(domain, iova, size, iotlb_gather);
 }
 EXPORT_SYMBOL_GPL(iommu_unmap_fast);
 
 size_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova,
 		    struct scatterlist *sg, unsigned int nents, int prot)
 {
-	struct scatterlist *s;
-	size_t mapped = 0;
-	unsigned int i, min_pagesz;
+	size_t len = 0, mapped = 0;
+	phys_addr_t start;
+	unsigned int i = 0;
 	int ret;
 
-	if (unlikely(domain->pgsize_bitmap == 0UL))
-		return 0;
+	while (i <= nents) {
+		phys_addr_t s_phys = sg_phys(sg);
 
-	min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
+		if (len && s_phys != start + len) {
+			ret = iommu_map(domain, iova + mapped, start, len, prot);
+			if (ret)
+				goto out_err;
 
-	for_each_sg(sg, s, nents, i) {
-		phys_addr_t phys = page_to_phys(sg_page(s)) + s->offset;
+			mapped += len;
+			len = 0;
+		}
 
-		/*
-		 * We are mapping on IOMMU page boundaries, so offset within
-		 * the page must be 0. However, the IOMMU may support pages
-		 * smaller than PAGE_SIZE, so s->offset may still represent
-		 * an offset of that boundary within the CPU page.
-		 */
-		if (!IS_ALIGNED(s->offset, min_pagesz))
-			goto out_err;
+		if (len) {
+			len += sg->length;
+		} else {
+			len = sg->length;
+			start = s_phys;
+		}
 
-		ret = iommu_map(domain, iova + mapped, phys, s->length, prot);
-		if (ret)
-			goto out_err;
-
-		mapped += s->length;
+		if (++i < nents)
+			sg = sg_next(sg);
 	}
 
 	return mapped;
@@ -1796,7 +2113,6 @@
 	struct iommu_domain_geometry *geometry;
 	bool *paging;
 	int ret = 0;
-	u32 *count;
 
 	switch (attr) {
 	case DOMAIN_ATTR_GEOMETRY:
@@ -1808,15 +2124,6 @@
 		paging  = data;
 		*paging = (domain->pgsize_bitmap != 0UL);
 		break;
-	case DOMAIN_ATTR_WINDOWS:
-		count = data;
-
-		if (domain->ops->domain_get_windows != NULL)
-			*count = domain->ops->domain_get_windows(domain);
-		else
-			ret = -ENODEV;
-
-		break;
 	default:
 		if (!domain->ops->domain_get_attr)
 			return -EINVAL;
@@ -1832,18 +2139,8 @@
 			  enum iommu_attr attr, void *data)
 {
 	int ret = 0;
-	u32 *count;
 
 	switch (attr) {
-	case DOMAIN_ATTR_WINDOWS:
-		count = data;
-
-		if (domain->ops->domain_set_windows != NULL)
-			ret = domain->ops->domain_set_windows(domain, *count);
-		else
-			ret = -ENODEV;
-
-		break;
 	default:
 		if (domain->ops->domain_set_attr == NULL)
 			return -EINVAL;
@@ -1889,24 +2186,22 @@
 	return region;
 }
 
-/* Request that a device is direct mapped by the IOMMU */
-int iommu_request_dm_for_dev(struct device *dev)
+static int
+request_default_domain_for_dev(struct device *dev, unsigned long type)
 {
-	struct iommu_domain *dm_domain;
+	struct iommu_domain *domain;
 	struct iommu_group *group;
 	int ret;
 
 	/* Device must already be in a group before calling this function */
-	group = iommu_group_get_for_dev(dev);
-	if (IS_ERR(group))
-		return PTR_ERR(group);
+	group = iommu_group_get(dev);
+	if (!group)
+		return -EINVAL;
 
 	mutex_lock(&group->mutex);
 
-	/* Check if the default domain is already direct mapped */
 	ret = 0;
-	if (group->default_domain &&
-	    group->default_domain->type == IOMMU_DOMAIN_IDENTITY)
+	if (group->default_domain && group->default_domain->type == type)
 		goto out;
 
 	/* Don't change mappings of existing devices */
@@ -1914,25 +2209,27 @@
 	if (iommu_group_device_count(group) != 1)
 		goto out;
 
-	/* Allocate a direct mapped domain */
 	ret = -ENOMEM;
-	dm_domain = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_IDENTITY);
-	if (!dm_domain)
+	domain = __iommu_domain_alloc(dev->bus, type);
+	if (!domain)
 		goto out;
 
 	/* Attach the device to the domain */
-	ret = __iommu_attach_group(dm_domain, group);
+	ret = __iommu_attach_group(domain, group);
 	if (ret) {
-		iommu_domain_free(dm_domain);
+		iommu_domain_free(domain);
 		goto out;
 	}
 
-	/* Make the direct mapped domain the default for this group */
+	iommu_group_create_direct_mappings(group, dev);
+
+	/* Make the domain the default for this group */
 	if (group->default_domain)
 		iommu_domain_free(group->default_domain);
-	group->default_domain = dm_domain;
+	group->default_domain = domain;
 
-	pr_info("Using direct mapping for device %s\n", dev_name(dev));
+	dev_info(dev, "Using iommu %s mapping\n",
+		 type == IOMMU_DOMAIN_DMA ? "dma" : "direct");
 
 	ret = 0;
 out:
@@ -1942,6 +2239,40 @@
 	return ret;
 }
 
+/* Request that a device is direct mapped by the IOMMU */
+int iommu_request_dm_for_dev(struct device *dev)
+{
+	return request_default_domain_for_dev(dev, IOMMU_DOMAIN_IDENTITY);
+}
+
+/* Request that a device can't be direct mapped by the IOMMU */
+int iommu_request_dma_domain_for_dev(struct device *dev)
+{
+	return request_default_domain_for_dev(dev, IOMMU_DOMAIN_DMA);
+}
+
+void iommu_set_default_passthrough(bool cmd_line)
+{
+	if (cmd_line)
+		iommu_set_cmd_line_dma_api();
+
+	iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY;
+}
+
+void iommu_set_default_translated(bool cmd_line)
+{
+	if (cmd_line)
+		iommu_set_cmd_line_dma_api();
+
+	iommu_def_domain_type = IOMMU_DOMAIN_DMA;
+}
+
+bool iommu_default_passthrough(void)
+{
+	return iommu_def_domain_type == IOMMU_DOMAIN_IDENTITY;
+}
+EXPORT_SYMBOL_GPL(iommu_default_passthrough);
+
 const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
 {
 	const struct iommu_ops *ops = NULL;
@@ -1960,7 +2291,7 @@
 int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
 		      const struct iommu_ops *ops)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
 	if (fwspec)
 		return ops == fwspec->ops ? 0 : -EINVAL;
@@ -1972,26 +2303,26 @@
 	of_node_get(to_of_node(iommu_fwnode));
 	fwspec->iommu_fwnode = iommu_fwnode;
 	fwspec->ops = ops;
-	dev->iommu_fwspec = fwspec;
+	dev_iommu_fwspec_set(dev, fwspec);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_init);
 
 void iommu_fwspec_free(struct device *dev)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 
 	if (fwspec) {
 		fwnode_handle_put(fwspec->iommu_fwnode);
 		kfree(fwspec);
-		dev->iommu_fwspec = NULL;
+		dev_iommu_fwspec_set(dev, NULL);
 	}
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_free);
 
 int iommu_fwspec_add_ids(struct device *dev, u32 *ids, int num_ids)
 {
-	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 	size_t size;
 	int i;
 
@@ -2000,11 +2331,11 @@
 
 	size = offsetof(struct iommu_fwspec, ids[fwspec->num_ids + num_ids]);
 	if (size > sizeof(*fwspec)) {
-		fwspec = krealloc(dev->iommu_fwspec, size, GFP_KERNEL);
+		fwspec = krealloc(fwspec, size, GFP_KERNEL);
 		if (!fwspec)
 			return -ENOMEM;
 
-		dev->iommu_fwspec = fwspec;
+		dev_iommu_fwspec_set(dev, fwspec);
 	}
 
 	for (i = 0; i < num_ids; i++)
@@ -2014,3 +2345,203 @@
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_fwspec_add_ids);
+
+/*
+ * Per device IOMMU features.
+ */
+bool iommu_dev_has_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_has_feat)
+		return ops->dev_has_feat(dev, feat);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_has_feature);
+
+int iommu_dev_enable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_enable_feat)
+		return ops->dev_enable_feat(dev, feat);
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_enable_feature);
+
+/*
+ * The device drivers should do the necessary cleanups before calling this.
+ * For example, before disabling the aux-domain feature, the device driver
+ * should detach all aux-domains. Otherwise, this will return -EBUSY.
+ */
+int iommu_dev_disable_feature(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_disable_feat)
+		return ops->dev_disable_feat(dev, feat);
+
+	return -EBUSY;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_disable_feature);
+
+bool iommu_dev_feature_enabled(struct device *dev, enum iommu_dev_features feat)
+{
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (ops && ops->dev_feat_enabled)
+		return ops->dev_feat_enabled(dev, feat);
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(iommu_dev_feature_enabled);
+
+/*
+ * Aux-domain specific attach/detach.
+ *
+ * Only works if iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX) returns
+ * true. Also, as long as domains are attached to a device through this
+ * interface, any tries to call iommu_attach_device() should fail
+ * (iommu_detach_device() can't fail, so we fail when trying to re-attach).
+ * This should make us safe against a device being attached to a guest as a
+ * whole while there are still pasid users on it (aux and sva).
+ */
+int iommu_aux_attach_device(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = -ENODEV;
+
+	if (domain->ops->aux_attach_dev)
+		ret = domain->ops->aux_attach_dev(domain, dev);
+
+	if (!ret)
+		trace_attach_device_to_domain(dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_aux_attach_device);
+
+void iommu_aux_detach_device(struct iommu_domain *domain, struct device *dev)
+{
+	if (domain->ops->aux_detach_dev) {
+		domain->ops->aux_detach_dev(domain, dev);
+		trace_detach_device_from_domain(dev);
+	}
+}
+EXPORT_SYMBOL_GPL(iommu_aux_detach_device);
+
+int iommu_aux_get_pasid(struct iommu_domain *domain, struct device *dev)
+{
+	int ret = -ENODEV;
+
+	if (domain->ops->aux_get_pasid)
+		ret = domain->ops->aux_get_pasid(domain, dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_aux_get_pasid);
+
+/**
+ * iommu_sva_bind_device() - Bind a process address space to a device
+ * @dev: the device
+ * @mm: the mm to bind, caller must hold a reference to it
+ *
+ * Create a bond between device and address space, allowing the device to access
+ * the mm using the returned PASID. If a bond already exists between @device and
+ * @mm, it is returned and an additional reference is taken. Caller must call
+ * iommu_sva_unbind_device() to release each reference.
+ *
+ * iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) must be called first, to
+ * initialize the required SVA features.
+ *
+ * On error, returns an ERR_PTR value.
+ */
+struct iommu_sva *
+iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void *drvdata)
+{
+	struct iommu_group *group;
+	struct iommu_sva *handle = ERR_PTR(-EINVAL);
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (!ops || !ops->sva_bind)
+		return ERR_PTR(-ENODEV);
+
+	group = iommu_group_get(dev);
+	if (!group)
+		return ERR_PTR(-ENODEV);
+
+	/* Ensure device count and domain don't change while we're binding */
+	mutex_lock(&group->mutex);
+
+	/*
+	 * To keep things simple, SVA currently doesn't support IOMMU groups
+	 * with more than one device. Existing SVA-capable systems are not
+	 * affected by the problems that required IOMMU groups (lack of ACS
+	 * isolation, device ID aliasing and other hardware issues).
+	 */
+	if (iommu_group_device_count(group) != 1)
+		goto out_unlock;
+
+	handle = ops->sva_bind(dev, mm, drvdata);
+
+out_unlock:
+	mutex_unlock(&group->mutex);
+	iommu_group_put(group);
+
+	return handle;
+}
+EXPORT_SYMBOL_GPL(iommu_sva_bind_device);
+
+/**
+ * iommu_sva_unbind_device() - Remove a bond created with iommu_sva_bind_device
+ * @handle: the handle returned by iommu_sva_bind_device()
+ *
+ * Put reference to a bond between device and address space. The device should
+ * not be issuing any more transaction for this PASID. All outstanding page
+ * requests for this PASID must have been flushed to the IOMMU.
+ *
+ * Returns 0 on success, or an error value
+ */
+void iommu_sva_unbind_device(struct iommu_sva *handle)
+{
+	struct iommu_group *group;
+	struct device *dev = handle->dev;
+	const struct iommu_ops *ops = dev->bus->iommu_ops;
+
+	if (!ops || !ops->sva_unbind)
+		return;
+
+	group = iommu_group_get(dev);
+	if (!group)
+		return;
+
+	mutex_lock(&group->mutex);
+	ops->sva_unbind(handle);
+	mutex_unlock(&group->mutex);
+
+	iommu_group_put(group);
+}
+EXPORT_SYMBOL_GPL(iommu_sva_unbind_device);
+
+int iommu_sva_set_ops(struct iommu_sva *handle,
+		      const struct iommu_sva_ops *sva_ops)
+{
+	if (handle->ops && handle->ops != sva_ops)
+		return -EEXIST;
+
+	handle->ops = sva_ops;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(iommu_sva_set_ops);
+
+int iommu_sva_get_pasid(struct iommu_sva *handle)
+{
+	const struct iommu_ops *ops = handle->dev->bus->iommu_ops;
+
+	if (!ops || !ops->sva_get_pasid)
+		return IOMMU_PASID_INVALID;
+
+	return ops->sva_get_pasid(handle);
+}
+EXPORT_SYMBOL_GPL(iommu_sva_get_pasid);