17 files changed, 7652 insertions, 0 deletions

diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig
new file mode 100644
index 000000000..80c5f9c16
--- /dev/null
+++ b/drivers/virt/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Virtualization support drivers
+#
+
+menuconfig VIRT_DRIVERS
+	bool "Virtualization drivers"
+	help
+	  Say Y here to get to see options for device drivers that support
+	  virtualization environments.
+
+	  If you say N, all options in this submenu will be skipped and disabled.
+
+if VIRT_DRIVERS
+
+config FSL_HV_MANAGER
+	tristate "Freescale hypervisor management driver"
+	depends on FSL_SOC
+	select EPAPR_PARAVIRT
+	help
+          The Freescale hypervisor management driver provides several services
+	  to drivers and applications related to the Freescale hypervisor:
+
+          1) An ioctl interface for querying and managing partitions.
+
+          2) A file interface to reading incoming doorbells.
+
+          3) An interrupt handler for shutting down the partition upon
+	     receiving the shutdown doorbell from a manager partition.
+
+          4) A kernel interface for receiving callbacks when a managed
+	     partition shuts down.
+
+source "drivers/virt/vboxguest/Kconfig"
+
+source "drivers/virt/nitro_enclaves/Kconfig"
+endif
diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
new file mode 100644
index 000000000..f28425ce4
--- /dev/null
+++ b/drivers/virt/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for drivers that support virtualization
+#
+
+obj-$(CONFIG_FSL_HV_MANAGER)	+= fsl_hypervisor.o
+obj-y				+= vboxguest/
+
+obj-$(CONFIG_NITRO_ENCLAVES)	+= nitro_enclaves/
diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c
new file mode 100644
index 000000000..46ee0a099
--- /dev/null
+++ b/drivers/virt/fsl_hypervisor.c
@@ -0,0 +1,935 @@
+/*
+ * Freescale Hypervisor Management Driver
+
+ * Copyright (C) 2008-2011 Freescale Semiconductor, Inc.
+ * Author: Timur Tabi <timur@freescale.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ * The Freescale hypervisor management driver provides several services to
+ * drivers and applications related to the Freescale hypervisor:
+ *
+ * 1. An ioctl interface for querying and managing partitions.
+ *
+ * 2. A file interface to reading incoming doorbells.
+ *
+ * 3. An interrupt handler for shutting down the partition upon receiving the
+ *    shutdown doorbell from a manager partition.
+ *
+ * 4. A kernel interface for receiving callbacks when a managed partition
+ *    shuts down.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/poll.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <linux/notifier.h>
+#include <linux/interrupt.h>
+
+#include <linux/io.h>
+#include <asm/fsl_hcalls.h>
+
+#include <linux/fsl_hypervisor.h>
+
+static BLOCKING_NOTIFIER_HEAD(failover_subscribers);
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_PARTITION_RESTART
+ *
+ * Restart a running partition
+ */
+static long ioctl_restart(struct fsl_hv_ioctl_restart __user *p)
+{
+	struct fsl_hv_ioctl_restart param;
+
+	/* Get the parameters from the user */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_restart)))
+		return -EFAULT;
+
+	param.ret = fh_partition_restart(param.partition);
+
+	if (copy_to_user(&p->ret, &param.ret, sizeof(__u32)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_PARTITION_STATUS
+ *
+ * Query the status of a partition
+ */
+static long ioctl_status(struct fsl_hv_ioctl_status __user *p)
+{
+	struct fsl_hv_ioctl_status param;
+	u32 status;
+
+	/* Get the parameters from the user */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_status)))
+		return -EFAULT;
+
+	param.ret = fh_partition_get_status(param.partition, &status);
+	if (!param.ret)
+		param.status = status;
+
+	if (copy_to_user(p, &param, sizeof(struct fsl_hv_ioctl_status)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_PARTITION_START
+ *
+ * Start a stopped partition.
+ */
+static long ioctl_start(struct fsl_hv_ioctl_start __user *p)
+{
+	struct fsl_hv_ioctl_start param;
+
+	/* Get the parameters from the user */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_start)))
+		return -EFAULT;
+
+	param.ret = fh_partition_start(param.partition, param.entry_point,
+				       param.load);
+
+	if (copy_to_user(&p->ret, &param.ret, sizeof(__u32)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_PARTITION_STOP
+ *
+ * Stop a running partition
+ */
+static long ioctl_stop(struct fsl_hv_ioctl_stop __user *p)
+{
+	struct fsl_hv_ioctl_stop param;
+
+	/* Get the parameters from the user */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_stop)))
+		return -EFAULT;
+
+	param.ret = fh_partition_stop(param.partition);
+
+	if (copy_to_user(&p->ret, &param.ret, sizeof(__u32)))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_MEMCPY
+ *
+ * The FH_MEMCPY hypercall takes an array of address/address/size structures
+ * to represent the data being copied.  As a convenience to the user, this
+ * ioctl takes a user-create buffer and a pointer to a guest physically
+ * contiguous buffer in the remote partition, and creates the
+ * address/address/size array for the hypercall.
+ */
+static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p)
+{
+	struct fsl_hv_ioctl_memcpy param;
+
+	struct page **pages = NULL;
+	void *sg_list_unaligned = NULL;
+	struct fh_sg_list *sg_list = NULL;
+
+	unsigned int num_pages;
+	unsigned long lb_offset; /* Offset within a page of the local buffer */
+
+	unsigned int i;
+	long ret = 0;
+	int num_pinned = 0; /* return value from get_user_pages_fast() */
+	phys_addr_t remote_paddr; /* The next address in the remote buffer */
+	uint32_t count; /* The number of bytes left to copy */
+
+	/* Get the parameters from the user */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_memcpy)))
+		return -EFAULT;
+
+	/*
+	 * One partition must be local, the other must be remote.  In other
+	 * words, if source and target are both -1, or are both not -1, then
+	 * return an error.
+	 */
+	if ((param.source == -1) == (param.target == -1))
+		return -EINVAL;
+
+	/*
+	 * The array of pages returned by get_user_pages_fast() covers only
+	 * page-aligned memory.  Since the user buffer is probably not
+	 * page-aligned, we need to handle the discrepancy.
+	 *
+	 * We calculate the offset within a page of the S/G list, and make
+	 * adjustments accordingly.  This will result in a page list that looks
+	 * like this:
+	 *
+	 *      ----    <-- first page starts before the buffer
+	 *     |    |
+	 *     |////|-> ----
+	 *     |////|  |    |
+	 *      ----   |    |
+	 *             |    |
+	 *      ----   |    |
+	 *     |////|  |    |
+	 *     |////|  |    |
+	 *     |////|  |    |
+	 *      ----   |    |
+	 *             |    |
+	 *      ----   |    |
+	 *     |////|  |    |
+	 *     |////|  |    |
+	 *     |////|  |    |
+	 *      ----   |    |
+	 *             |    |
+	 *      ----   |    |
+	 *     |////|  |    |
+	 *     |////|-> ----
+	 *     |    |   <-- last page ends after the buffer
+	 *      ----
+	 *
+	 * The distance between the start of the first page and the start of the
+	 * buffer is lb_offset.  The hashed (///) areas are the parts of the
+	 * page list that contain the actual buffer.
+	 *
+	 * The advantage of this approach is that the number of pages is
+	 * equal to the number of entries in the S/G list that we give to the
+	 * hypervisor.
+	 */
+	lb_offset = param.local_vaddr & (PAGE_SIZE - 1);
+	if (param.count == 0 ||
+	    param.count > U64_MAX - lb_offset - PAGE_SIZE + 1)
+		return -EINVAL;
+	num_pages = (param.count + lb_offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
+
+	/* Allocate the buffers we need */
+
+	/*
+	 * 'pages' is an array of struct page pointers that's initialized by
+	 * get_user_pages_fast().
+	 */
+	pages = kcalloc(num_pages, sizeof(struct page *), GFP_KERNEL);
+	if (!pages) {
+		pr_debug("fsl-hv: could not allocate page list\n");
+		return -ENOMEM;
+	}
+
+	/*
+	 * sg_list is the list of fh_sg_list objects that we pass to the
+	 * hypervisor.
+	 */
+	sg_list_unaligned = kmalloc(num_pages * sizeof(struct fh_sg_list) +
+		sizeof(struct fh_sg_list) - 1, GFP_KERNEL);
+	if (!sg_list_unaligned) {
+		pr_debug("fsl-hv: could not allocate S/G list\n");
+		ret = -ENOMEM;
+		goto free_pages;
+	}
+	sg_list = PTR_ALIGN(sg_list_unaligned, sizeof(struct fh_sg_list));
+
+	/* Get the physical addresses of the source buffer */
+	num_pinned = get_user_pages_fast(param.local_vaddr - lb_offset,
+		num_pages, param.source != -1 ? FOLL_WRITE : 0, pages);
+
+	if (num_pinned != num_pages) {
+		pr_debug("fsl-hv: could not lock source buffer\n");
+		ret = (num_pinned < 0) ? num_pinned : -EFAULT;
+		goto exit;
+	}
+
+	/*
+	 * Build the fh_sg_list[] array.  The first page is special
+	 * because it's misaligned.
+	 */
+	if (param.source == -1) {
+		sg_list[0].source = page_to_phys(pages[0]) + lb_offset;
+		sg_list[0].target = param.remote_paddr;
+	} else {
+		sg_list[0].source = param.remote_paddr;
+		sg_list[0].target = page_to_phys(pages[0]) + lb_offset;
+	}
+	sg_list[0].size = min_t(uint64_t, param.count, PAGE_SIZE - lb_offset);
+
+	remote_paddr = param.remote_paddr + sg_list[0].size;
+	count = param.count - sg_list[0].size;
+
+	for (i = 1; i < num_pages; i++) {
+		if (param.source == -1) {
+			/* local to remote */
+			sg_list[i].source = page_to_phys(pages[i]);
+			sg_list[i].target = remote_paddr;
+		} else {
+			/* remote to local */
+			sg_list[i].source = remote_paddr;
+			sg_list[i].target = page_to_phys(pages[i]);
+		}
+		sg_list[i].size = min_t(uint64_t, count, PAGE_SIZE);
+
+		remote_paddr += sg_list[i].size;
+		count -= sg_list[i].size;
+	}
+
+	param.ret = fh_partition_memcpy(param.source, param.target,
+		virt_to_phys(sg_list), num_pages);
+
+exit:
+	if (pages && (num_pinned > 0)) {
+		for (i = 0; i < num_pinned; i++)
+			put_page(pages[i]);
+	}
+
+	kfree(sg_list_unaligned);
+free_pages:
+	kfree(pages);
+
+	if (!ret)
+		if (copy_to_user(&p->ret, &param.ret, sizeof(__u32)))
+			return -EFAULT;
+
+	return ret;
+}
+
+/*
+ * Ioctl interface for FSL_HV_IOCTL_DOORBELL
+ *
+ * Ring a doorbell
+ */
+static long ioctl_doorbell(struct fsl_hv_ioctl_doorbell __user *p)
+{
+	struct fsl_hv_ioctl_doorbell param;
+
+	/* Get the parameters from the user. */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_doorbell)))
+		return -EFAULT;
+
+	param.ret = ev_doorbell_send(param.doorbell);
+
+	if (copy_to_user(&p->ret, &param.ret, sizeof(__u32)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long ioctl_dtprop(struct fsl_hv_ioctl_prop __user *p, int set)
+{
+	struct fsl_hv_ioctl_prop param;
+	char __user *upath, *upropname;
+	void __user *upropval;
+	char *path, *propname;
+	void *propval;
+	int ret = 0;
+
+	/* Get the parameters from the user. */
+	if (copy_from_user(&param, p, sizeof(struct fsl_hv_ioctl_prop)))
+		return -EFAULT;
+
+	upath = (char __user *)(uintptr_t)param.path;
+	upropname = (char __user *)(uintptr_t)param.propname;
+	upropval = (void __user *)(uintptr_t)param.propval;
+
+	path = strndup_user(upath, FH_DTPROP_MAX_PATHLEN);
+	if (IS_ERR(path))
+		return PTR_ERR(path);
+
+	propname = strndup_user(upropname, FH_DTPROP_MAX_PATHLEN);
+	if (IS_ERR(propname)) {
+		ret = PTR_ERR(propname);
+		goto err_free_path;
+	}
+
+	if (param.proplen > FH_DTPROP_MAX_PROPLEN) {
+		ret = -EINVAL;
+		goto err_free_propname;
+	}
+
+	propval = kmalloc(param.proplen, GFP_KERNEL);
+	if (!propval) {
+		ret = -ENOMEM;
+		goto err_free_propname;
+	}
+
+	if (set) {
+		if (copy_from_user(propval, upropval, param.proplen)) {
+			ret = -EFAULT;
+			goto err_free_propval;
+		}
+
+		param.ret = fh_partition_set_dtprop(param.handle,
+						    virt_to_phys(path),
+						    virt_to_phys(propname),
+						    virt_to_phys(propval),
+						    param.proplen);
+	} else {
+		param.ret = fh_partition_get_dtprop(param.handle,
+						    virt_to_phys(path),
+						    virt_to_phys(propname),
+						    virt_to_phys(propval),
+						    &param.proplen);
+
+		if (param.ret == 0) {
+			if (copy_to_user(upropval, propval, param.proplen) ||
+			    put_user(param.proplen, &p->proplen)) {
+				ret = -EFAULT;
+				goto err_free_propval;
+			}
+		}
+	}
+
+	if (put_user(param.ret, &p->ret))
+		ret = -EFAULT;
+
+err_free_propval:
+	kfree(propval);
+err_free_propname:
+	kfree(propname);
+err_free_path:
+	kfree(path);
+
+	return ret;
+}
+
+/*
+ * Ioctl main entry point
+ */
+static long fsl_hv_ioctl(struct file *file, unsigned int cmd,
+			 unsigned long argaddr)
+{
+	void __user *arg = (void __user *)argaddr;
+	long ret;
+
+	switch (cmd) {
+	case FSL_HV_IOCTL_PARTITION_RESTART:
+		ret = ioctl_restart(arg);
+		break;
+	case FSL_HV_IOCTL_PARTITION_GET_STATUS:
+		ret = ioctl_status(arg);
+		break;
+	case FSL_HV_IOCTL_PARTITION_START:
+		ret = ioctl_start(arg);
+		break;
+	case FSL_HV_IOCTL_PARTITION_STOP:
+		ret = ioctl_stop(arg);
+		break;
+	case FSL_HV_IOCTL_MEMCPY:
+		ret = ioctl_memcpy(arg);
+		break;
+	case FSL_HV_IOCTL_DOORBELL:
+		ret = ioctl_doorbell(arg);
+		break;
+	case FSL_HV_IOCTL_GETPROP:
+		ret = ioctl_dtprop(arg, 0);
+		break;
+	case FSL_HV_IOCTL_SETPROP:
+		ret = ioctl_dtprop(arg, 1);
+		break;
+	default:
+		pr_debug("fsl-hv: bad ioctl dir=%u type=%u cmd=%u size=%u\n",
+			 _IOC_DIR(cmd), _IOC_TYPE(cmd), _IOC_NR(cmd),
+			 _IOC_SIZE(cmd));
+		return -ENOTTY;
+	}
+
+	return ret;
+}
+
+/* Linked list of processes that have us open */
+static struct list_head db_list;
+
+/* spinlock for db_list */
+static DEFINE_SPINLOCK(db_list_lock);
+
+/* The size of the doorbell event queue.  This must be a power of two. */
+#define QSIZE	16
+
+/* Returns the next head/tail pointer, wrapping around the queue if necessary */
+#define nextp(x) (((x) + 1) & (QSIZE - 1))
+
+/* Per-open data structure */
+struct doorbell_queue {
+	struct list_head list;
+	spinlock_t lock;
+	wait_queue_head_t wait;
+	unsigned int head;
+	unsigned int tail;
+	uint32_t q[QSIZE];
+};
+
+/* Linked list of ISRs that we registered */
+struct list_head isr_list;
+
+/* Per-ISR data structure */
+struct doorbell_isr {
+	struct list_head list;
+	unsigned int irq;
+	uint32_t doorbell;	/* The doorbell handle */
+	uint32_t partition;	/* The partition handle, if used */
+};
+
+/*
+ * Add a doorbell to all of the doorbell queues
+ */
+static void fsl_hv_queue_doorbell(uint32_t doorbell)
+{
+	struct doorbell_queue *dbq;
+	unsigned long flags;
+
+	/* Prevent another core from modifying db_list */
+	spin_lock_irqsave(&db_list_lock, flags);
+
+	list_for_each_entry(dbq, &db_list, list) {
+		if (dbq->head != nextp(dbq->tail)) {
+			dbq->q[dbq->tail] = doorbell;
+			/*
+			 * This memory barrier eliminates the need to grab
+			 * the spinlock for dbq.
+			 */
+			smp_wmb();
+			dbq->tail = nextp(dbq->tail);
+			wake_up_interruptible(&dbq->wait);
+		}
+	}
+
+	spin_unlock_irqrestore(&db_list_lock, flags);
+}
+
+/*
+ * Interrupt handler for all doorbells
+ *
+ * We use the same interrupt handler for all doorbells.  Whenever a doorbell
+ * is rung, and we receive an interrupt, we just put the handle for that
+ * doorbell (passed to us as *data) into all of the queues.
+ */
+static irqreturn_t fsl_hv_isr(int irq, void *data)
+{
+	fsl_hv_queue_doorbell((uintptr_t) data);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * State change thread function
+ *
+ * The state change notification arrives in an interrupt, but we can't call
+ * blocking_notifier_call_chain() in an interrupt handler.  We could call
+ * atomic_notifier_call_chain(), but that would require the clients' call-back
+ * function to run in interrupt context.  Since we don't want to impose that
+ * restriction on the clients, we use a threaded IRQ to process the
+ * notification in kernel context.
+ */
+static irqreturn_t fsl_hv_state_change_thread(int irq, void *data)
+{
+	struct doorbell_isr *dbisr = data;
+
+	blocking_notifier_call_chain(&failover_subscribers, dbisr->partition,
+				     NULL);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Interrupt handler for state-change doorbells
+ */
+static irqreturn_t fsl_hv_state_change_isr(int irq, void *data)
+{
+	unsigned int status;
+	struct doorbell_isr *dbisr = data;
+	int ret;
+
+	/* It's still a doorbell, so add it to all the queues. */
+	fsl_hv_queue_doorbell(dbisr->doorbell);
+
+	/* Determine the new state, and if it's stopped, notify the clients. */
+	ret = fh_partition_get_status(dbisr->partition, &status);
+	if (!ret && (status == FH_PARTITION_STOPPED))
+		return IRQ_WAKE_THREAD;
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Returns a bitmask indicating whether a read will block
+ */
+static __poll_t fsl_hv_poll(struct file *filp, struct poll_table_struct *p)
+{
+	struct doorbell_queue *dbq = filp->private_data;
+	unsigned long flags;
+	__poll_t mask;
+
+	spin_lock_irqsave(&dbq->lock, flags);
+
+	poll_wait(filp, &dbq->wait, p);
+	mask = (dbq->head == dbq->tail) ? 0 : (EPOLLIN | EPOLLRDNORM);
+
+	spin_unlock_irqrestore(&dbq->lock, flags);
+
+	return mask;
+}
+
+/*
+ * Return the handles for any incoming doorbells
+ *
+ * If there are doorbell handles in the queue for this open instance, then
+ * return them to the caller as an array of 32-bit integers.  Otherwise,
+ * block until there is at least one handle to return.
+ */
+static ssize_t fsl_hv_read(struct file *filp, char __user *buf, size_t len,
+			   loff_t *off)
+{
+	struct doorbell_queue *dbq = filp->private_data;
+	uint32_t __user *p = (uint32_t __user *) buf; /* for put_user() */
+	unsigned long flags;
+	ssize_t count = 0;
+
+	/* Make sure we stop when the user buffer is full. */
+	while (len >= sizeof(uint32_t)) {
+		uint32_t dbell;	/* Local copy of doorbell queue data */
+
+		spin_lock_irqsave(&dbq->lock, flags);
+
+		/*
+		 * If the queue is empty, then either we're done or we need
+		 * to block.  If the application specified O_NONBLOCK, then
+		 * we return the appropriate error code.
+		 */
+		if (dbq->head == dbq->tail) {
+			spin_unlock_irqrestore(&dbq->lock, flags);
+			if (count)
+				break;
+			if (filp->f_flags & O_NONBLOCK)
+				return -EAGAIN;
+			if (wait_event_interruptible(dbq->wait,
+						     dbq->head != dbq->tail))
+				return -ERESTARTSYS;
+			continue;
+		}
+
+		/*
+		 * Even though we have an smp_wmb() in the ISR, the core
+		 * might speculatively execute the "dbell = ..." below while
+		 * it's evaluating the if-statement above.  In that case, the
+		 * value put into dbell could be stale if the core accepts the
+		 * speculation. To prevent that, we need a read memory barrier
+		 * here as well.
+		 */
+		smp_rmb();
+
+		/* Copy the data to a temporary local buffer, because
+		 * we can't call copy_to_user() from inside a spinlock
+		 */
+		dbell = dbq->q[dbq->head];
+		dbq->head = nextp(dbq->head);
+
+		spin_unlock_irqrestore(&dbq->lock, flags);
+
+		if (put_user(dbell, p))
+			return -EFAULT;
+		p++;
+		count += sizeof(uint32_t);
+		len -= sizeof(uint32_t);
+	}
+
+	return count;
+}
+
+/*
+ * Open the driver and prepare for reading doorbells.
+ *
+ * Every time an application opens the driver, we create a doorbell queue
+ * for that file handle.  This queue is used for any incoming doorbells.
+ */
+static int fsl_hv_open(struct inode *inode, struct file *filp)
+{
+	struct doorbell_queue *dbq;
+	unsigned long flags;
+	int ret = 0;
+
+	dbq = kzalloc(sizeof(struct doorbell_queue), GFP_KERNEL);
+	if (!dbq) {
+		pr_err("fsl-hv: out of memory\n");
+		return -ENOMEM;
+	}
+
+	spin_lock_init(&dbq->lock);
+	init_waitqueue_head(&dbq->wait);
+
+	spin_lock_irqsave(&db_list_lock, flags);
+	list_add(&dbq->list, &db_list);
+	spin_unlock_irqrestore(&db_list_lock, flags);
+
+	filp->private_data = dbq;
+
+	return ret;
+}
+
+/*
+ * Close the driver
+ */
+static int fsl_hv_close(struct inode *inode, struct file *filp)
+{
+	struct doorbell_queue *dbq = filp->private_data;
+	unsigned long flags;
+
+	int ret = 0;
+
+	spin_lock_irqsave(&db_list_lock, flags);
+	list_del(&dbq->list);
+	spin_unlock_irqrestore(&db_list_lock, flags);
+
+	kfree(dbq);
+
+	return ret;
+}
+
+static const struct file_operations fsl_hv_fops = {
+	.owner = THIS_MODULE,
+	.open = fsl_hv_open,
+	.release = fsl_hv_close,
+	.poll = fsl_hv_poll,
+	.read = fsl_hv_read,
+	.unlocked_ioctl = fsl_hv_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+};
+
+static struct miscdevice fsl_hv_misc_dev = {
+	MISC_DYNAMIC_MINOR,
+	"fsl-hv",
+	&fsl_hv_fops
+};
+
+static irqreturn_t fsl_hv_shutdown_isr(int irq, void *data)
+{
+	orderly_poweroff(false);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Returns the handle of the parent of the given node
+ *
+ * The handle is the value of the 'hv-handle' property
+ */
+static int get_parent_handle(struct device_node *np)
+{
+	struct device_node *parent;
+	const uint32_t *prop;
+	uint32_t handle;
+	int len;
+
+	parent = of_get_parent(np);
+	if (!parent)
+		/* It's not really possible for this to fail */
+		return -ENODEV;
+
+	/*
+	 * The proper name for the handle property is "hv-handle", but some
+	 * older versions of the hypervisor used "reg".
+	 */
+	prop = of_get_property(parent, "hv-handle", &len);
+	if (!prop)
+		prop = of_get_property(parent, "reg", &len);
+
+	if (!prop || (len != sizeof(uint32_t))) {
+		/* This can happen only if the node is malformed */
+		of_node_put(parent);
+		return -ENODEV;
+	}
+
+	handle = be32_to_cpup(prop);
+	of_node_put(parent);
+
+	return handle;
+}
+
+/*
+ * Register a callback for failover events
+ *
+ * This function is called by device drivers to register their callback
+ * functions for fail-over events.
+ */
+int fsl_hv_failover_register(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&failover_subscribers, nb);
+}
+EXPORT_SYMBOL(fsl_hv_failover_register);
+
+/*
+ * Unregister a callback for failover events
+ */
+int fsl_hv_failover_unregister(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&failover_subscribers, nb);
+}
+EXPORT_SYMBOL(fsl_hv_failover_unregister);
+
+/*
+ * Return TRUE if we're running under FSL hypervisor
+ *
+ * This function checks to see if we're running under the Freescale
+ * hypervisor, and returns zero if we're not, or non-zero if we are.
+ *
+ * First, it checks if MSR[GS]==1, which means we're running under some
+ * hypervisor.  Then it checks if there is a hypervisor node in the device
+ * tree.  Currently, that means there needs to be a node in the root called
+ * "hypervisor" and which has a property named "fsl,hv-version".
+ */
+static int has_fsl_hypervisor(void)
+{
+	struct device_node *node;
+	int ret;
+
+	node = of_find_node_by_path("/hypervisor");
+	if (!node)
+		return 0;
+
+	ret = of_find_property(node, "fsl,hv-version", NULL) != NULL;
+
+	of_node_put(node);
+
+	return ret;
+}
+
+/*
+ * Freescale hypervisor management driver init
+ *
+ * This function is called when this module is loaded.
+ *
+ * Register ourselves as a miscellaneous driver.  This will register the
+ * fops structure and create the right sysfs entries for udev.
+ */
+static int __init fsl_hypervisor_init(void)
+{
+	struct device_node *np;
+	struct doorbell_isr *dbisr, *n;
+	int ret;
+
+	pr_info("Freescale hypervisor management driver\n");
+
+	if (!has_fsl_hypervisor()) {
+		pr_info("fsl-hv: no hypervisor found\n");
+		return -ENODEV;
+	}
+
+	ret = misc_register(&fsl_hv_misc_dev);
+	if (ret) {
+		pr_err("fsl-hv: cannot register device\n");
+		return ret;
+	}
+
+	INIT_LIST_HEAD(&db_list);
+	INIT_LIST_HEAD(&isr_list);
+
+	for_each_compatible_node(np, NULL, "epapr,hv-receive-doorbell") {
+		unsigned int irq;
+		const uint32_t *handle;
+
+		handle = of_get_property(np, "interrupts", NULL);
+		irq = irq_of_parse_and_map(np, 0);
+		if (!handle || (irq == NO_IRQ)) {
+			pr_err("fsl-hv: no 'interrupts' property in %pOF node\n",
+				np);
+			continue;
+		}
+
+		dbisr = kzalloc(sizeof(*dbisr), GFP_KERNEL);
+		if (!dbisr)
+			goto out_of_memory;
+
+		dbisr->irq = irq;
+		dbisr->doorbell = be32_to_cpup(handle);
+
+		if (of_device_is_compatible(np, "fsl,hv-shutdown-doorbell")) {
+			/* The shutdown doorbell gets its own ISR */
+			ret = request_irq(irq, fsl_hv_shutdown_isr, 0,
+					  np->name, NULL);
+		} else if (of_device_is_compatible(np,
+			"fsl,hv-state-change-doorbell")) {
+			/*
+			 * The state change doorbell triggers a notification if
+			 * the state of the managed partition changes to
+			 * "stopped". We need a separate interrupt handler for
+			 * that, and we also need to know the handle of the
+			 * target partition, not just the handle of the
+			 * doorbell.
+			 */
+			dbisr->partition = ret = get_parent_handle(np);
+			if (ret < 0) {
+				pr_err("fsl-hv: node %pOF has missing or "
+				       "malformed parent\n", np);
+				kfree(dbisr);
+				continue;
+			}
+			ret = request_threaded_irq(irq, fsl_hv_state_change_isr,
+						   fsl_hv_state_change_thread,
+						   0, np->name, dbisr);
+		} else
+			ret = request_irq(irq, fsl_hv_isr, 0, np->name, dbisr);
+
+		if (ret < 0) {
+			pr_err("fsl-hv: could not request irq %u for node %pOF\n",
+			       irq, np);
+			kfree(dbisr);
+			continue;
+		}
+
+		list_add(&dbisr->list, &isr_list);
+
+		pr_info("fsl-hv: registered handler for doorbell %u\n",
+			dbisr->doorbell);
+	}
+
+	return 0;
+
+out_of_memory:
+	list_for_each_entry_safe(dbisr, n, &isr_list, list) {
+		free_irq(dbisr->irq, dbisr);
+		list_del(&dbisr->list);
+		kfree(dbisr);
+	}
+
+	misc_deregister(&fsl_hv_misc_dev);
+
+	return -ENOMEM;
+}
+
+/*
+ * Freescale hypervisor management driver termination
+ *
+ * This function is called when this driver is unloaded.
+ */
+static void __exit fsl_hypervisor_exit(void)
+{
+	struct doorbell_isr *dbisr, *n;
+
+	list_for_each_entry_safe(dbisr, n, &isr_list, list) {
+		free_irq(dbisr->irq, dbisr);
+		list_del(&dbisr->list);
+		kfree(dbisr);
+	}
+
+	misc_deregister(&fsl_hv_misc_dev);
+}
+
+module_init(fsl_hypervisor_init);
+module_exit(fsl_hypervisor_exit);
+
+MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
+MODULE_DESCRIPTION("Freescale hypervisor management driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/virt/nitro_enclaves/Kconfig b/drivers/virt/nitro_enclaves/Kconfig
new file mode 100644
index 000000000..8c9387a23
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/Kconfig
@@ -0,0 +1,20 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+
+# Amazon Nitro Enclaves (NE) support.
+# Nitro is a hypervisor that has been developed by Amazon.
+
+# TODO: Add dependency for ARM64 once NE is supported on Arm platforms. For now,
+# the NE kernel driver can be built for aarch64 arch.
+# depends on (ARM64 || X86) && HOTPLUG_CPU && PCI && SMP
+
+config NITRO_ENCLAVES
+	tristate "Nitro Enclaves Support"
+	depends on X86 && HOTPLUG_CPU && PCI && SMP
+	help
+	  This driver consists of support for enclave lifetime management
+	  for Nitro Enclaves (NE).
+
+	  To compile this driver as a module, choose M here.
+	  The module will be called nitro_enclaves.
diff --git a/drivers/virt/nitro_enclaves/Makefile b/drivers/virt/nitro_enclaves/Makefile
new file mode 100644
index 000000000..da61260f2
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+
+# Enclave lifetime management support for Nitro Enclaves (NE).
+
+obj-$(CONFIG_NITRO_ENCLAVES) += nitro_enclaves.o
+
+nitro_enclaves-y := ne_pci_dev.o ne_misc_dev.o
diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.c b/drivers/virt/nitro_enclaves/ne_misc_dev.c
new file mode 100644
index 000000000..e21e1e86a
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c
@@ -0,0 +1,1722 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+/**
+ * DOC: Enclave lifetime management driver for Nitro Enclaves (NE).
+ * Nitro is a hypervisor that has been developed by Amazon.
+ */
+
+#include <linux/anon_inodes.h>
+#include <linux/capability.h>
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <linux/file.h>
+#include <linux/hugetlb.h>
+#include <linux/limits.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/nitro_enclaves.h>
+#include <linux/pci.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <uapi/linux/vm_sockets.h>
+
+#include "ne_misc_dev.h"
+#include "ne_pci_dev.h"
+
+/**
+ * NE_CPUS_SIZE - Size for max 128 CPUs, for now, in a cpu-list string, comma
+ *		  separated. The NE CPU pool includes CPUs from a single NUMA
+ *		  node.
+ */
+#define NE_CPUS_SIZE		(512)
+
+/**
+ * NE_EIF_LOAD_OFFSET - The offset where to copy the Enclave Image Format (EIF)
+ *			image in enclave memory.
+ */
+#define NE_EIF_LOAD_OFFSET	(8 * 1024UL * 1024UL)
+
+/**
+ * NE_MIN_ENCLAVE_MEM_SIZE - The minimum memory size an enclave can be launched
+ *			     with.
+ */
+#define NE_MIN_ENCLAVE_MEM_SIZE	(64 * 1024UL * 1024UL)
+
+/**
+ * NE_MIN_MEM_REGION_SIZE - The minimum size of an enclave memory region.
+ */
+#define NE_MIN_MEM_REGION_SIZE	(2 * 1024UL * 1024UL)
+
+/**
+ * NE_PARENT_VM_CID - The CID for the vsock device of the primary / parent VM.
+ */
+#define NE_PARENT_VM_CID	(3)
+
+static long ne_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+
+static const struct file_operations ne_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= noop_llseek,
+	.unlocked_ioctl	= ne_ioctl,
+};
+
+static struct miscdevice ne_misc_dev = {
+	.minor	= MISC_DYNAMIC_MINOR,
+	.name	= "nitro_enclaves",
+	.fops	= &ne_fops,
+	.mode	= 0660,
+};
+
+struct ne_devs ne_devs = {
+	.ne_misc_dev	= &ne_misc_dev,
+};
+
+/*
+ * TODO: Update logic to create new sysfs entries instead of using
+ * a kernel parameter e.g. if multiple sysfs files needed.
+ */
+static int ne_set_kernel_param(const char *val, const struct kernel_param *kp);
+
+static const struct kernel_param_ops ne_cpu_pool_ops = {
+	.get	= param_get_string,
+	.set	= ne_set_kernel_param,
+};
+
+static char ne_cpus[NE_CPUS_SIZE];
+static struct kparam_string ne_cpus_arg = {
+	.maxlen	= sizeof(ne_cpus),
+	.string	= ne_cpus,
+};
+
+module_param_cb(ne_cpus, &ne_cpu_pool_ops, &ne_cpus_arg, 0644);
+/* https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html#cpu-lists */
+MODULE_PARM_DESC(ne_cpus, "<cpu-list> - CPU pool used for Nitro Enclaves");
+
+/**
+ * struct ne_cpu_pool - CPU pool used for Nitro Enclaves.
+ * @avail_threads_per_core:	Available full CPU cores to be dedicated to
+ *				enclave(s). The cpumasks from the array, indexed
+ *				by core id, contain all the threads from the
+ *				available cores, that are not set for created
+ *				enclave(s). The full CPU cores are part of the
+ *				NE CPU pool.
+ * @mutex:			Mutex for the access to the NE CPU pool.
+ * @nr_parent_vm_cores :	The size of the available threads per core array.
+ *				The total number of CPU cores available on the
+ *				primary / parent VM.
+ * @nr_threads_per_core:	The number of threads that a full CPU core has.
+ * @numa_node:			NUMA node of the CPUs in the pool.
+ */
+struct ne_cpu_pool {
+	cpumask_var_t	*avail_threads_per_core;
+	struct mutex	mutex;
+	unsigned int	nr_parent_vm_cores;
+	unsigned int	nr_threads_per_core;
+	int		numa_node;
+};
+
+static struct ne_cpu_pool ne_cpu_pool;
+
+/**
+ * ne_check_enclaves_created() - Verify if at least one enclave has been created.
+ * @void:	No parameters provided.
+ *
+ * Context: Process context.
+ * Return:
+ * * True if at least one enclave is created.
+ * * False otherwise.
+ */
+static bool ne_check_enclaves_created(void)
+{
+	struct ne_pci_dev *ne_pci_dev = ne_devs.ne_pci_dev;
+	bool ret = false;
+
+	if (!ne_pci_dev)
+		return ret;
+
+	mutex_lock(&ne_pci_dev->enclaves_list_mutex);
+
+	if (!list_empty(&ne_pci_dev->enclaves_list))
+		ret = true;
+
+	mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
+
+	return ret;
+}
+
+/**
+ * ne_setup_cpu_pool() - Set the NE CPU pool after handling sanity checks such
+ *			 as not sharing CPU cores with the primary / parent VM
+ *			 or not using CPU 0, which should remain available for
+ *			 the primary / parent VM. Offline the CPUs from the
+ *			 pool after the checks passed.
+ * @ne_cpu_list:	The CPU list used for setting NE CPU pool.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_setup_cpu_pool(const char *ne_cpu_list)
+{
+	int core_id = -1;
+	unsigned int cpu = 0;
+	cpumask_var_t cpu_pool;
+	unsigned int cpu_sibling = 0;
+	unsigned int i = 0;
+	int numa_node = -1;
+	int rc = -EINVAL;
+
+	if (!zalloc_cpumask_var(&cpu_pool, GFP_KERNEL))
+		return -ENOMEM;
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	rc = cpulist_parse(ne_cpu_list, cpu_pool);
+	if (rc < 0) {
+		pr_err("%s: Error in cpulist parse [rc=%d]\n", ne_misc_dev.name, rc);
+
+		goto free_pool_cpumask;
+	}
+
+	cpu = cpumask_any(cpu_pool);
+	if (cpu >= nr_cpu_ids) {
+		pr_err("%s: No CPUs available in CPU pool\n", ne_misc_dev.name);
+
+		rc = -EINVAL;
+
+		goto free_pool_cpumask;
+	}
+
+	/*
+	 * Check if the CPUs are online, to further get info about them
+	 * e.g. numa node, core id, siblings.
+	 */
+	for_each_cpu(cpu, cpu_pool)
+		if (cpu_is_offline(cpu)) {
+			pr_err("%s: CPU %d is offline, has to be online to get its metadata\n",
+			       ne_misc_dev.name, cpu);
+
+			rc = -EINVAL;
+
+			goto free_pool_cpumask;
+		}
+
+	/*
+	 * Check if the CPUs from the NE CPU pool are from the same NUMA node.
+	 */
+	for_each_cpu(cpu, cpu_pool)
+		if (numa_node < 0) {
+			numa_node = cpu_to_node(cpu);
+			if (numa_node < 0) {
+				pr_err("%s: Invalid NUMA node %d\n",
+				       ne_misc_dev.name, numa_node);
+
+				rc = -EINVAL;
+
+				goto free_pool_cpumask;
+			}
+		} else {
+			if (numa_node != cpu_to_node(cpu)) {
+				pr_err("%s: CPUs with different NUMA nodes\n",
+				       ne_misc_dev.name);
+
+				rc = -EINVAL;
+
+				goto free_pool_cpumask;
+			}
+		}
+
+	/*
+	 * Check if CPU 0 and its siblings are included in the provided CPU pool
+	 * They should remain available for the primary / parent VM.
+	 */
+	if (cpumask_test_cpu(0, cpu_pool)) {
+		pr_err("%s: CPU 0 has to remain available\n", ne_misc_dev.name);
+
+		rc = -EINVAL;
+
+		goto free_pool_cpumask;
+	}
+
+	for_each_cpu(cpu_sibling, topology_sibling_cpumask(0)) {
+		if (cpumask_test_cpu(cpu_sibling, cpu_pool)) {
+			pr_err("%s: CPU sibling %d for CPU 0 is in CPU pool\n",
+			       ne_misc_dev.name, cpu_sibling);
+
+			rc = -EINVAL;
+
+			goto free_pool_cpumask;
+		}
+	}
+
+	/*
+	 * Check if CPU siblings are included in the provided CPU pool. The
+	 * expectation is that full CPU cores are made available in the CPU pool
+	 * for enclaves.
+	 */
+	for_each_cpu(cpu, cpu_pool) {
+		for_each_cpu(cpu_sibling, topology_sibling_cpumask(cpu)) {
+			if (!cpumask_test_cpu(cpu_sibling, cpu_pool)) {
+				pr_err("%s: CPU %d is not in CPU pool\n",
+				       ne_misc_dev.name, cpu_sibling);
+
+				rc = -EINVAL;
+
+				goto free_pool_cpumask;
+			}
+		}
+	}
+
+	/* Calculate the number of threads from a full CPU core. */
+	cpu = cpumask_any(cpu_pool);
+	for_each_cpu(cpu_sibling, topology_sibling_cpumask(cpu))
+		ne_cpu_pool.nr_threads_per_core++;
+
+	ne_cpu_pool.nr_parent_vm_cores = nr_cpu_ids / ne_cpu_pool.nr_threads_per_core;
+
+	ne_cpu_pool.avail_threads_per_core = kcalloc(ne_cpu_pool.nr_parent_vm_cores,
+					     sizeof(*ne_cpu_pool.avail_threads_per_core),
+					     GFP_KERNEL);
+	if (!ne_cpu_pool.avail_threads_per_core) {
+		rc = -ENOMEM;
+
+		goto free_pool_cpumask;
+	}
+
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		if (!zalloc_cpumask_var(&ne_cpu_pool.avail_threads_per_core[i], GFP_KERNEL)) {
+			rc = -ENOMEM;
+
+			goto free_cores_cpumask;
+		}
+
+	/*
+	 * Split the NE CPU pool in threads per core to keep the CPU topology
+	 * after offlining the CPUs.
+	 */
+	for_each_cpu(cpu, cpu_pool) {
+		core_id = topology_core_id(cpu);
+		if (core_id < 0 || core_id >= ne_cpu_pool.nr_parent_vm_cores) {
+			pr_err("%s: Invalid core id  %d for CPU %d\n",
+			       ne_misc_dev.name, core_id, cpu);
+
+			rc = -EINVAL;
+
+			goto clear_cpumask;
+		}
+
+		cpumask_set_cpu(cpu, ne_cpu_pool.avail_threads_per_core[core_id]);
+	}
+
+	/*
+	 * CPUs that are given to enclave(s) should not be considered online
+	 * by Linux anymore, as the hypervisor will degrade them to floating.
+	 * The physical CPUs (full cores) are carved out of the primary / parent
+	 * VM and given to the enclave VM. The same number of vCPUs would run
+	 * on less pCPUs for the primary / parent VM.
+	 *
+	 * We offline them here, to not degrade performance and expose correct
+	 * topology to Linux and user space.
+	 */
+	for_each_cpu(cpu, cpu_pool) {
+		rc = remove_cpu(cpu);
+		if (rc != 0) {
+			pr_err("%s: CPU %d is not offlined [rc=%d]\n",
+			       ne_misc_dev.name, cpu, rc);
+
+			goto online_cpus;
+		}
+	}
+
+	free_cpumask_var(cpu_pool);
+
+	ne_cpu_pool.numa_node = numa_node;
+
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	return 0;
+
+online_cpus:
+	for_each_cpu(cpu, cpu_pool)
+		add_cpu(cpu);
+clear_cpumask:
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		cpumask_clear(ne_cpu_pool.avail_threads_per_core[i]);
+free_cores_cpumask:
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		free_cpumask_var(ne_cpu_pool.avail_threads_per_core[i]);
+	kfree(ne_cpu_pool.avail_threads_per_core);
+free_pool_cpumask:
+	free_cpumask_var(cpu_pool);
+	ne_cpu_pool.nr_parent_vm_cores = 0;
+	ne_cpu_pool.nr_threads_per_core = 0;
+	ne_cpu_pool.numa_node = -1;
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	return rc;
+}
+
+/**
+ * ne_teardown_cpu_pool() - Online the CPUs from the NE CPU pool and cleanup the
+ *			    CPU pool.
+ * @void:	No parameters provided.
+ *
+ * Context: Process context.
+ */
+static void ne_teardown_cpu_pool(void)
+{
+	unsigned int cpu = 0;
+	unsigned int i = 0;
+	int rc = -EINVAL;
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	if (!ne_cpu_pool.nr_parent_vm_cores) {
+		mutex_unlock(&ne_cpu_pool.mutex);
+
+		return;
+	}
+
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++) {
+		for_each_cpu(cpu, ne_cpu_pool.avail_threads_per_core[i]) {
+			rc = add_cpu(cpu);
+			if (rc != 0)
+				pr_err("%s: CPU %d is not onlined [rc=%d]\n",
+				       ne_misc_dev.name, cpu, rc);
+		}
+
+		cpumask_clear(ne_cpu_pool.avail_threads_per_core[i]);
+
+		free_cpumask_var(ne_cpu_pool.avail_threads_per_core[i]);
+	}
+
+	kfree(ne_cpu_pool.avail_threads_per_core);
+	ne_cpu_pool.nr_parent_vm_cores = 0;
+	ne_cpu_pool.nr_threads_per_core = 0;
+	ne_cpu_pool.numa_node = -1;
+
+	mutex_unlock(&ne_cpu_pool.mutex);
+}
+
+/**
+ * ne_set_kernel_param() - Set the NE CPU pool value via the NE kernel parameter.
+ * @val:	NE CPU pool string value.
+ * @kp :	NE kernel parameter associated with the NE CPU pool.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_set_kernel_param(const char *val, const struct kernel_param *kp)
+{
+	char error_val[] = "";
+	int rc = -EINVAL;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (ne_check_enclaves_created()) {
+		pr_err("%s: The CPU pool is used by enclave(s)\n", ne_misc_dev.name);
+
+		return -EPERM;
+	}
+
+	ne_teardown_cpu_pool();
+
+	rc = ne_setup_cpu_pool(val);
+	if (rc < 0) {
+		pr_err("%s: Error in setup CPU pool [rc=%d]\n", ne_misc_dev.name, rc);
+
+		param_set_copystring(error_val, kp);
+
+		return rc;
+	}
+
+	rc = param_set_copystring(val, kp);
+	if (rc < 0) {
+		pr_err("%s: Error in param set copystring [rc=%d]\n", ne_misc_dev.name, rc);
+
+		ne_teardown_cpu_pool();
+
+		param_set_copystring(error_val, kp);
+
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_donated_cpu() - Check if the provided CPU is already used by the enclave.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @cpu:		CPU to check if already used.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * True if the provided CPU is already used by the enclave.
+ * * False otherwise.
+ */
+static bool ne_donated_cpu(struct ne_enclave *ne_enclave, unsigned int cpu)
+{
+	if (cpumask_test_cpu(cpu, ne_enclave->vcpu_ids))
+		return true;
+
+	return false;
+}
+
+/**
+ * ne_get_unused_core_from_cpu_pool() - Get the id of a full core from the
+ *					NE CPU pool.
+ * @void:	No parameters provided.
+ *
+ * Context: Process context. This function is called with the ne_enclave and
+ *	    ne_cpu_pool mutexes held.
+ * Return:
+ * * Core id.
+ * * -1 if no CPU core available in the pool.
+ */
+static int ne_get_unused_core_from_cpu_pool(void)
+{
+	int core_id = -1;
+	unsigned int i = 0;
+
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		if (!cpumask_empty(ne_cpu_pool.avail_threads_per_core[i])) {
+			core_id = i;
+
+			break;
+		}
+
+	return core_id;
+}
+
+/**
+ * ne_set_enclave_threads_per_core() - Set the threads of the provided core in
+ *				       the enclave data structure.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @core_id:		Core id to get its threads from the NE CPU pool.
+ * @vcpu_id:		vCPU id part of the provided core.
+ *
+ * Context: Process context. This function is called with the ne_enclave and
+ *	    ne_cpu_pool mutexes held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_set_enclave_threads_per_core(struct ne_enclave *ne_enclave,
+					   int core_id, u32 vcpu_id)
+{
+	unsigned int cpu = 0;
+
+	if (core_id < 0 && vcpu_id == 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "No CPUs available in NE CPU pool\n");
+
+		return -NE_ERR_NO_CPUS_AVAIL_IN_POOL;
+	}
+
+	if (core_id < 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "CPU %d is not in NE CPU pool\n", vcpu_id);
+
+		return -NE_ERR_VCPU_NOT_IN_CPU_POOL;
+	}
+
+	if (core_id >= ne_enclave->nr_parent_vm_cores) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Invalid core id %d - ne_enclave\n", core_id);
+
+		return -NE_ERR_VCPU_INVALID_CPU_CORE;
+	}
+
+	for_each_cpu(cpu, ne_cpu_pool.avail_threads_per_core[core_id])
+		cpumask_set_cpu(cpu, ne_enclave->threads_per_core[core_id]);
+
+	cpumask_clear(ne_cpu_pool.avail_threads_per_core[core_id]);
+
+	return 0;
+}
+
+/**
+ * ne_get_cpu_from_cpu_pool() - Get a CPU from the NE CPU pool, either from the
+ *				remaining sibling(s) of a CPU core or the first
+ *				sibling of a new CPU core.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @vcpu_id:		vCPU to get from the NE CPU pool.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_get_cpu_from_cpu_pool(struct ne_enclave *ne_enclave, u32 *vcpu_id)
+{
+	int core_id = -1;
+	unsigned int cpu = 0;
+	unsigned int i = 0;
+	int rc = -EINVAL;
+
+	/*
+	 * If previously allocated a thread of a core to this enclave, first
+	 * check remaining sibling(s) for new CPU allocations, so that full
+	 * CPU cores are used for the enclave.
+	 */
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
+		for_each_cpu(cpu, ne_enclave->threads_per_core[i])
+			if (!ne_donated_cpu(ne_enclave, cpu)) {
+				*vcpu_id = cpu;
+
+				return 0;
+			}
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	/*
+	 * If no remaining siblings, get a core from the NE CPU pool and keep
+	 * track of all the threads in the enclave threads per core data structure.
+	 */
+	core_id = ne_get_unused_core_from_cpu_pool();
+
+	rc = ne_set_enclave_threads_per_core(ne_enclave, core_id, *vcpu_id);
+	if (rc < 0)
+		goto unlock_mutex;
+
+	*vcpu_id = cpumask_any(ne_enclave->threads_per_core[core_id]);
+
+	rc = 0;
+
+unlock_mutex:
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	return rc;
+}
+
+/**
+ * ne_get_vcpu_core_from_cpu_pool() - Get from the NE CPU pool the id of the
+ *				      core associated with the provided vCPU.
+ * @vcpu_id:	Provided vCPU id to get its associated core id.
+ *
+ * Context: Process context. This function is called with the ne_enclave and
+ *	    ne_cpu_pool mutexes held.
+ * Return:
+ * * Core id.
+ * * -1 if the provided vCPU is not in the pool.
+ */
+static int ne_get_vcpu_core_from_cpu_pool(u32 vcpu_id)
+{
+	int core_id = -1;
+	unsigned int i = 0;
+
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		if (cpumask_test_cpu(vcpu_id, ne_cpu_pool.avail_threads_per_core[i])) {
+			core_id = i;
+
+			break;
+	}
+
+	return core_id;
+}
+
+/**
+ * ne_check_cpu_in_cpu_pool() - Check if the given vCPU is in the available CPUs
+ *				from the pool.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @vcpu_id:		ID of the vCPU to check if available in the NE CPU pool.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_check_cpu_in_cpu_pool(struct ne_enclave *ne_enclave, u32 vcpu_id)
+{
+	int core_id = -1;
+	unsigned int i = 0;
+	int rc = -EINVAL;
+
+	if (ne_donated_cpu(ne_enclave, vcpu_id)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "CPU %d already used\n", vcpu_id);
+
+		return -NE_ERR_VCPU_ALREADY_USED;
+	}
+
+	/*
+	 * If previously allocated a thread of a core to this enclave, but not
+	 * the full core, first check remaining sibling(s).
+	 */
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
+		if (cpumask_test_cpu(vcpu_id, ne_enclave->threads_per_core[i]))
+			return 0;
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	/*
+	 * If no remaining siblings, get from the NE CPU pool the core
+	 * associated with the vCPU and keep track of all the threads in the
+	 * enclave threads per core data structure.
+	 */
+	core_id = ne_get_vcpu_core_from_cpu_pool(vcpu_id);
+
+	rc = ne_set_enclave_threads_per_core(ne_enclave, core_id, vcpu_id);
+	if (rc < 0)
+		goto unlock_mutex;
+
+	rc = 0;
+
+unlock_mutex:
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	return rc;
+}
+
+/**
+ * ne_add_vcpu_ioctl() - Add a vCPU to the slot associated with the current
+ *			 enclave.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @vcpu_id:		ID of the CPU to be associated with the given slot,
+ *			apic id on x86.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_add_vcpu_ioctl(struct ne_enclave *ne_enclave, u32 vcpu_id)
+{
+	struct ne_pci_dev_cmd_reply cmd_reply = {};
+	struct pci_dev *pdev = ne_devs.ne_pci_dev->pdev;
+	int rc = -EINVAL;
+	struct slot_add_vcpu_req slot_add_vcpu_req = {};
+
+	if (ne_enclave->mm != current->mm)
+		return -EIO;
+
+	slot_add_vcpu_req.slot_uid = ne_enclave->slot_uid;
+	slot_add_vcpu_req.vcpu_id = vcpu_id;
+
+	rc = ne_do_request(pdev, SLOT_ADD_VCPU,
+			   &slot_add_vcpu_req, sizeof(slot_add_vcpu_req),
+			   &cmd_reply, sizeof(cmd_reply));
+	if (rc < 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in slot add vCPU [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	cpumask_set_cpu(vcpu_id, ne_enclave->vcpu_ids);
+
+	ne_enclave->nr_vcpus++;
+
+	return 0;
+}
+
+/**
+ * ne_sanity_check_user_mem_region() - Sanity check the user space memory
+ *				       region received during the set user
+ *				       memory region ioctl call.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @mem_region :	User space memory region to be sanity checked.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_sanity_check_user_mem_region(struct ne_enclave *ne_enclave,
+	struct ne_user_memory_region mem_region)
+{
+	struct ne_mem_region *ne_mem_region = NULL;
+
+	if (ne_enclave->mm != current->mm)
+		return -EIO;
+
+	if (mem_region.memory_size & (NE_MIN_MEM_REGION_SIZE - 1)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "User space memory size is not multiple of 2 MiB\n");
+
+		return -NE_ERR_INVALID_MEM_REGION_SIZE;
+	}
+
+	if (!IS_ALIGNED(mem_region.userspace_addr, NE_MIN_MEM_REGION_SIZE)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "User space address is not 2 MiB aligned\n");
+
+		return -NE_ERR_UNALIGNED_MEM_REGION_ADDR;
+	}
+
+	if ((mem_region.userspace_addr & (NE_MIN_MEM_REGION_SIZE - 1)) ||
+	    !access_ok((void __user *)(unsigned long)mem_region.userspace_addr,
+		       mem_region.memory_size)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Invalid user space address range\n");
+
+		return -NE_ERR_INVALID_MEM_REGION_ADDR;
+	}
+
+	list_for_each_entry(ne_mem_region, &ne_enclave->mem_regions_list,
+			    mem_region_list_entry) {
+		u64 memory_size = ne_mem_region->memory_size;
+		u64 userspace_addr = ne_mem_region->userspace_addr;
+
+		if ((userspace_addr <= mem_region.userspace_addr &&
+		    mem_region.userspace_addr < (userspace_addr + memory_size)) ||
+		    (mem_region.userspace_addr <= userspace_addr &&
+		    (mem_region.userspace_addr + mem_region.memory_size) > userspace_addr)) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "User space memory region already used\n");
+
+			return -NE_ERR_MEM_REGION_ALREADY_USED;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * ne_sanity_check_user_mem_region_page() - Sanity check a page from the user space
+ *					    memory region received during the set
+ *					    user memory region ioctl call.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @mem_region_page:	Page from the user space memory region to be sanity checked.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_sanity_check_user_mem_region_page(struct ne_enclave *ne_enclave,
+						struct page *mem_region_page)
+{
+	if (!PageHuge(mem_region_page)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Not a hugetlbfs page\n");
+
+		return -NE_ERR_MEM_NOT_HUGE_PAGE;
+	}
+
+	if (page_size(mem_region_page) & (NE_MIN_MEM_REGION_SIZE - 1)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Page size not multiple of 2 MiB\n");
+
+		return -NE_ERR_INVALID_PAGE_SIZE;
+	}
+
+	if (ne_enclave->numa_node != page_to_nid(mem_region_page)) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Page is not from NUMA node %d\n",
+				    ne_enclave->numa_node);
+
+		return -NE_ERR_MEM_DIFFERENT_NUMA_NODE;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_set_user_memory_region_ioctl() - Add user space memory region to the slot
+ *				       associated with the current enclave.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @mem_region :	User space memory region to be associated with the given slot.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_set_user_memory_region_ioctl(struct ne_enclave *ne_enclave,
+	struct ne_user_memory_region mem_region)
+{
+	long gup_rc = 0;
+	unsigned long i = 0;
+	unsigned long max_nr_pages = 0;
+	unsigned long memory_size = 0;
+	struct ne_mem_region *ne_mem_region = NULL;
+	unsigned long nr_phys_contig_mem_regions = 0;
+	struct pci_dev *pdev = ne_devs.ne_pci_dev->pdev;
+	struct page **phys_contig_mem_regions = NULL;
+	int rc = -EINVAL;
+
+	rc = ne_sanity_check_user_mem_region(ne_enclave, mem_region);
+	if (rc < 0)
+		return rc;
+
+	ne_mem_region = kzalloc(sizeof(*ne_mem_region), GFP_KERNEL);
+	if (!ne_mem_region)
+		return -ENOMEM;
+
+	max_nr_pages = mem_region.memory_size / NE_MIN_MEM_REGION_SIZE;
+
+	ne_mem_region->pages = kcalloc(max_nr_pages, sizeof(*ne_mem_region->pages),
+				       GFP_KERNEL);
+	if (!ne_mem_region->pages) {
+		rc = -ENOMEM;
+
+		goto free_mem_region;
+	}
+
+	phys_contig_mem_regions = kcalloc(max_nr_pages, sizeof(*phys_contig_mem_regions),
+					  GFP_KERNEL);
+	if (!phys_contig_mem_regions) {
+		rc = -ENOMEM;
+
+		goto free_mem_region;
+	}
+
+	do {
+		i = ne_mem_region->nr_pages;
+
+		if (i == max_nr_pages) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Reached max nr of pages in the pages data struct\n");
+
+			rc = -ENOMEM;
+
+			goto put_pages;
+		}
+
+		gup_rc = get_user_pages(mem_region.userspace_addr + memory_size, 1, FOLL_GET,
+					ne_mem_region->pages + i, NULL);
+		if (gup_rc < 0) {
+			rc = gup_rc;
+
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Error in get user pages [rc=%d]\n", rc);
+
+			goto put_pages;
+		}
+
+		rc = ne_sanity_check_user_mem_region_page(ne_enclave, ne_mem_region->pages[i]);
+		if (rc < 0)
+			goto put_pages;
+
+		/*
+		 * TODO: Update once handled non-contiguous memory regions
+		 * received from user space or contiguous physical memory regions
+		 * larger than 2 MiB e.g. 8 MiB.
+		 */
+		phys_contig_mem_regions[i] = ne_mem_region->pages[i];
+
+		memory_size += page_size(ne_mem_region->pages[i]);
+
+		ne_mem_region->nr_pages++;
+	} while (memory_size < mem_region.memory_size);
+
+	/*
+	 * TODO: Update once handled non-contiguous memory regions received
+	 * from user space or contiguous physical memory regions larger than
+	 * 2 MiB e.g. 8 MiB.
+	 */
+	nr_phys_contig_mem_regions = ne_mem_region->nr_pages;
+
+	if ((ne_enclave->nr_mem_regions + nr_phys_contig_mem_regions) >
+	    ne_enclave->max_mem_regions) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Reached max memory regions %lld\n",
+				    ne_enclave->max_mem_regions);
+
+		rc = -NE_ERR_MEM_MAX_REGIONS;
+
+		goto put_pages;
+	}
+
+	for (i = 0; i < nr_phys_contig_mem_regions; i++) {
+		u64 phys_region_addr = page_to_phys(phys_contig_mem_regions[i]);
+		u64 phys_region_size = page_size(phys_contig_mem_regions[i]);
+
+		if (phys_region_size & (NE_MIN_MEM_REGION_SIZE - 1)) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Physical mem region size is not multiple of 2 MiB\n");
+
+			rc = -EINVAL;
+
+			goto put_pages;
+		}
+
+		if (!IS_ALIGNED(phys_region_addr, NE_MIN_MEM_REGION_SIZE)) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Physical mem region address is not 2 MiB aligned\n");
+
+			rc = -EINVAL;
+
+			goto put_pages;
+		}
+	}
+
+	ne_mem_region->memory_size = mem_region.memory_size;
+	ne_mem_region->userspace_addr = mem_region.userspace_addr;
+
+	list_add(&ne_mem_region->mem_region_list_entry, &ne_enclave->mem_regions_list);
+
+	for (i = 0; i < nr_phys_contig_mem_regions; i++) {
+		struct ne_pci_dev_cmd_reply cmd_reply = {};
+		struct slot_add_mem_req slot_add_mem_req = {};
+
+		slot_add_mem_req.slot_uid = ne_enclave->slot_uid;
+		slot_add_mem_req.paddr = page_to_phys(phys_contig_mem_regions[i]);
+		slot_add_mem_req.size = page_size(phys_contig_mem_regions[i]);
+
+		rc = ne_do_request(pdev, SLOT_ADD_MEM,
+				   &slot_add_mem_req, sizeof(slot_add_mem_req),
+				   &cmd_reply, sizeof(cmd_reply));
+		if (rc < 0) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Error in slot add mem [rc=%d]\n", rc);
+
+			kfree(phys_contig_mem_regions);
+
+			/*
+			 * Exit here without put pages as memory regions may
+			 * already been added.
+			 */
+			return rc;
+		}
+
+		ne_enclave->mem_size += slot_add_mem_req.size;
+		ne_enclave->nr_mem_regions++;
+	}
+
+	kfree(phys_contig_mem_regions);
+
+	return 0;
+
+put_pages:
+	for (i = 0; i < ne_mem_region->nr_pages; i++)
+		put_page(ne_mem_region->pages[i]);
+free_mem_region:
+	kfree(phys_contig_mem_regions);
+	kfree(ne_mem_region->pages);
+	kfree(ne_mem_region);
+
+	return rc;
+}
+
+/**
+ * ne_start_enclave_ioctl() - Trigger enclave start after the enclave resources,
+ *			      such as memory and CPU, have been set.
+ * @ne_enclave :		Private data associated with the current enclave.
+ * @enclave_start_info :	Enclave info that includes enclave cid and flags.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_start_enclave_ioctl(struct ne_enclave *ne_enclave,
+	struct ne_enclave_start_info *enclave_start_info)
+{
+	struct ne_pci_dev_cmd_reply cmd_reply = {};
+	unsigned int cpu = 0;
+	struct enclave_start_req enclave_start_req = {};
+	unsigned int i = 0;
+	struct pci_dev *pdev = ne_devs.ne_pci_dev->pdev;
+	int rc = -EINVAL;
+
+	if (!ne_enclave->nr_mem_regions) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Enclave has no mem regions\n");
+
+		return -NE_ERR_NO_MEM_REGIONS_ADDED;
+	}
+
+	if (ne_enclave->mem_size < NE_MIN_ENCLAVE_MEM_SIZE) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Enclave memory is less than %ld\n",
+				    NE_MIN_ENCLAVE_MEM_SIZE);
+
+		return -NE_ERR_ENCLAVE_MEM_MIN_SIZE;
+	}
+
+	if (!ne_enclave->nr_vcpus) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Enclave has no vCPUs\n");
+
+		return -NE_ERR_NO_VCPUS_ADDED;
+	}
+
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
+		for_each_cpu(cpu, ne_enclave->threads_per_core[i])
+			if (!cpumask_test_cpu(cpu, ne_enclave->vcpu_ids)) {
+				dev_err_ratelimited(ne_misc_dev.this_device,
+						    "Full CPU cores not used\n");
+
+				return -NE_ERR_FULL_CORES_NOT_USED;
+			}
+
+	enclave_start_req.enclave_cid = enclave_start_info->enclave_cid;
+	enclave_start_req.flags = enclave_start_info->flags;
+	enclave_start_req.slot_uid = ne_enclave->slot_uid;
+
+	rc = ne_do_request(pdev, ENCLAVE_START,
+			   &enclave_start_req, sizeof(enclave_start_req),
+			   &cmd_reply, sizeof(cmd_reply));
+	if (rc < 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in enclave start [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	ne_enclave->state = NE_STATE_RUNNING;
+
+	enclave_start_info->enclave_cid = cmd_reply.enclave_cid;
+
+	return 0;
+}
+
+/**
+ * ne_enclave_ioctl() - Ioctl function provided by the enclave file.
+ * @file:	File associated with this ioctl function.
+ * @cmd:	The command that is set for the ioctl call.
+ * @arg:	The argument that is provided for the ioctl call.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static long ne_enclave_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct ne_enclave *ne_enclave = file->private_data;
+
+	switch (cmd) {
+	case NE_ADD_VCPU: {
+		int rc = -EINVAL;
+		u32 vcpu_id = 0;
+
+		if (copy_from_user(&vcpu_id, (void __user *)arg, sizeof(vcpu_id)))
+			return -EFAULT;
+
+		mutex_lock(&ne_enclave->enclave_info_mutex);
+
+		if (ne_enclave->state != NE_STATE_INIT) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Enclave is not in init state\n");
+
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return -NE_ERR_NOT_IN_INIT_STATE;
+		}
+
+		if (vcpu_id >= (ne_enclave->nr_parent_vm_cores *
+		    ne_enclave->nr_threads_per_core)) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "vCPU id higher than max CPU id\n");
+
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return -NE_ERR_INVALID_VCPU;
+		}
+
+		if (!vcpu_id) {
+			/* Use the CPU pool for choosing a CPU for the enclave. */
+			rc = ne_get_cpu_from_cpu_pool(ne_enclave, &vcpu_id);
+			if (rc < 0) {
+				dev_err_ratelimited(ne_misc_dev.this_device,
+						    "Error in get CPU from pool [rc=%d]\n",
+						    rc);
+
+				mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+				return rc;
+			}
+		} else {
+			/* Check if the provided vCPU is available in the NE CPU pool. */
+			rc = ne_check_cpu_in_cpu_pool(ne_enclave, vcpu_id);
+			if (rc < 0) {
+				dev_err_ratelimited(ne_misc_dev.this_device,
+						    "Error in check CPU %d in pool [rc=%d]\n",
+						    vcpu_id, rc);
+
+				mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+				return rc;
+			}
+		}
+
+		rc = ne_add_vcpu_ioctl(ne_enclave, vcpu_id);
+		if (rc < 0) {
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return rc;
+		}
+
+		mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+		if (copy_to_user((void __user *)arg, &vcpu_id, sizeof(vcpu_id)))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	case NE_GET_IMAGE_LOAD_INFO: {
+		struct ne_image_load_info image_load_info = {};
+
+		if (copy_from_user(&image_load_info, (void __user *)arg, sizeof(image_load_info)))
+			return -EFAULT;
+
+		mutex_lock(&ne_enclave->enclave_info_mutex);
+
+		if (ne_enclave->state != NE_STATE_INIT) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Enclave is not in init state\n");
+
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return -NE_ERR_NOT_IN_INIT_STATE;
+		}
+
+		mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+		if (!image_load_info.flags ||
+		    image_load_info.flags >= NE_IMAGE_LOAD_MAX_FLAG_VAL) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Incorrect flag in enclave image load info\n");
+
+			return -NE_ERR_INVALID_FLAG_VALUE;
+		}
+
+		if (image_load_info.flags == NE_EIF_IMAGE)
+			image_load_info.memory_offset = NE_EIF_LOAD_OFFSET;
+
+		if (copy_to_user((void __user *)arg, &image_load_info, sizeof(image_load_info)))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	case NE_SET_USER_MEMORY_REGION: {
+		struct ne_user_memory_region mem_region = {};
+		int rc = -EINVAL;
+
+		if (copy_from_user(&mem_region, (void __user *)arg, sizeof(mem_region)))
+			return -EFAULT;
+
+		if (mem_region.flags >= NE_MEMORY_REGION_MAX_FLAG_VAL) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Incorrect flag for user memory region\n");
+
+			return -NE_ERR_INVALID_FLAG_VALUE;
+		}
+
+		mutex_lock(&ne_enclave->enclave_info_mutex);
+
+		if (ne_enclave->state != NE_STATE_INIT) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Enclave is not in init state\n");
+
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return -NE_ERR_NOT_IN_INIT_STATE;
+		}
+
+		rc = ne_set_user_memory_region_ioctl(ne_enclave, mem_region);
+		if (rc < 0) {
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return rc;
+		}
+
+		mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+		return 0;
+	}
+
+	case NE_START_ENCLAVE: {
+		struct ne_enclave_start_info enclave_start_info = {};
+		int rc = -EINVAL;
+
+		if (copy_from_user(&enclave_start_info, (void __user *)arg,
+				   sizeof(enclave_start_info)))
+			return -EFAULT;
+
+		if (enclave_start_info.flags >= NE_ENCLAVE_START_MAX_FLAG_VAL) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Incorrect flag in enclave start info\n");
+
+			return -NE_ERR_INVALID_FLAG_VALUE;
+		}
+
+		/*
+		 * Do not use well-known CIDs - 0, 1, 2 - for enclaves.
+		 * VMADDR_CID_ANY = -1U
+		 * VMADDR_CID_HYPERVISOR = 0
+		 * VMADDR_CID_LOCAL = 1
+		 * VMADDR_CID_HOST = 2
+		 * Note: 0 is used as a placeholder to auto-generate an enclave CID.
+		 * http://man7.org/linux/man-pages/man7/vsock.7.html
+		 */
+		if (enclave_start_info.enclave_cid > 0 &&
+		    enclave_start_info.enclave_cid <= VMADDR_CID_HOST) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Well-known CID value, not to be used for enclaves\n");
+
+			return -NE_ERR_INVALID_ENCLAVE_CID;
+		}
+
+		if (enclave_start_info.enclave_cid == U32_MAX) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Well-known CID value, not to be used for enclaves\n");
+
+			return -NE_ERR_INVALID_ENCLAVE_CID;
+		}
+
+		/*
+		 * Do not use the CID of the primary / parent VM for enclaves.
+		 */
+		if (enclave_start_info.enclave_cid == NE_PARENT_VM_CID) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "CID of the parent VM, not to be used for enclaves\n");
+
+			return -NE_ERR_INVALID_ENCLAVE_CID;
+		}
+
+		/* 64-bit CIDs are not yet supported for the vsock device. */
+		if (enclave_start_info.enclave_cid > U32_MAX) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "64-bit CIDs not yet supported for the vsock device\n");
+
+			return -NE_ERR_INVALID_ENCLAVE_CID;
+		}
+
+		mutex_lock(&ne_enclave->enclave_info_mutex);
+
+		if (ne_enclave->state != NE_STATE_INIT) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Enclave is not in init state\n");
+
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return -NE_ERR_NOT_IN_INIT_STATE;
+		}
+
+		rc = ne_start_enclave_ioctl(ne_enclave, &enclave_start_info);
+		if (rc < 0) {
+			mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+			return rc;
+		}
+
+		mutex_unlock(&ne_enclave->enclave_info_mutex);
+
+		if (copy_to_user((void __user *)arg, &enclave_start_info,
+				 sizeof(enclave_start_info)))
+			return -EFAULT;
+
+		return 0;
+	}
+
+	default:
+		return -ENOTTY;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_enclave_remove_all_mem_region_entries() - Remove all memory region entries
+ *						from the enclave data structure.
+ * @ne_enclave :	Private data associated with the current enclave.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ */
+static void ne_enclave_remove_all_mem_region_entries(struct ne_enclave *ne_enclave)
+{
+	unsigned long i = 0;
+	struct ne_mem_region *ne_mem_region = NULL;
+	struct ne_mem_region *ne_mem_region_tmp = NULL;
+
+	list_for_each_entry_safe(ne_mem_region, ne_mem_region_tmp,
+				 &ne_enclave->mem_regions_list,
+				 mem_region_list_entry) {
+		list_del(&ne_mem_region->mem_region_list_entry);
+
+		for (i = 0; i < ne_mem_region->nr_pages; i++)
+			put_page(ne_mem_region->pages[i]);
+
+		kfree(ne_mem_region->pages);
+
+		kfree(ne_mem_region);
+	}
+}
+
+/**
+ * ne_enclave_remove_all_vcpu_id_entries() - Remove all vCPU id entries from
+ *					     the enclave data structure.
+ * @ne_enclave :	Private data associated with the current enclave.
+ *
+ * Context: Process context. This function is called with the ne_enclave mutex held.
+ */
+static void ne_enclave_remove_all_vcpu_id_entries(struct ne_enclave *ne_enclave)
+{
+	unsigned int cpu = 0;
+	unsigned int i = 0;
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++) {
+		for_each_cpu(cpu, ne_enclave->threads_per_core[i])
+			/* Update the available NE CPU pool. */
+			cpumask_set_cpu(cpu, ne_cpu_pool.avail_threads_per_core[i]);
+
+		free_cpumask_var(ne_enclave->threads_per_core[i]);
+	}
+
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	kfree(ne_enclave->threads_per_core);
+
+	free_cpumask_var(ne_enclave->vcpu_ids);
+}
+
+/**
+ * ne_pci_dev_remove_enclave_entry() - Remove the enclave entry from the data
+ *				       structure that is part of the NE PCI
+ *				       device private data.
+ * @ne_enclave :	Private data associated with the current enclave.
+ * @ne_pci_dev :	Private data associated with the PCI device.
+ *
+ * Context: Process context. This function is called with the ne_pci_dev enclave
+ *	    mutex held.
+ */
+static void ne_pci_dev_remove_enclave_entry(struct ne_enclave *ne_enclave,
+					    struct ne_pci_dev *ne_pci_dev)
+{
+	struct ne_enclave *ne_enclave_entry = NULL;
+	struct ne_enclave *ne_enclave_entry_tmp = NULL;
+
+	list_for_each_entry_safe(ne_enclave_entry, ne_enclave_entry_tmp,
+				 &ne_pci_dev->enclaves_list, enclave_list_entry) {
+		if (ne_enclave_entry->slot_uid == ne_enclave->slot_uid) {
+			list_del(&ne_enclave_entry->enclave_list_entry);
+
+			break;
+		}
+	}
+}
+
+/**
+ * ne_enclave_release() - Release function provided by the enclave file.
+ * @inode:	Inode associated with this file release function.
+ * @file:	File associated with this release function.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_enclave_release(struct inode *inode, struct file *file)
+{
+	struct ne_pci_dev_cmd_reply cmd_reply = {};
+	struct enclave_stop_req enclave_stop_request = {};
+	struct ne_enclave *ne_enclave = file->private_data;
+	struct ne_pci_dev *ne_pci_dev = ne_devs.ne_pci_dev;
+	struct pci_dev *pdev = ne_pci_dev->pdev;
+	int rc = -EINVAL;
+	struct slot_free_req slot_free_req = {};
+
+	if (!ne_enclave)
+		return 0;
+
+	/*
+	 * Early exit in case there is an error in the enclave creation logic
+	 * and fput() is called on the cleanup path.
+	 */
+	if (!ne_enclave->slot_uid)
+		return 0;
+
+	/*
+	 * Acquire the enclave list mutex before the enclave mutex
+	 * in order to avoid deadlocks with @ref ne_event_work_handler.
+	 */
+	mutex_lock(&ne_pci_dev->enclaves_list_mutex);
+	mutex_lock(&ne_enclave->enclave_info_mutex);
+
+	if (ne_enclave->state != NE_STATE_INIT && ne_enclave->state != NE_STATE_STOPPED) {
+		enclave_stop_request.slot_uid = ne_enclave->slot_uid;
+
+		rc = ne_do_request(pdev, ENCLAVE_STOP,
+				   &enclave_stop_request, sizeof(enclave_stop_request),
+				   &cmd_reply, sizeof(cmd_reply));
+		if (rc < 0) {
+			dev_err_ratelimited(ne_misc_dev.this_device,
+					    "Error in enclave stop [rc=%d]\n", rc);
+
+			goto unlock_mutex;
+		}
+
+		memset(&cmd_reply, 0, sizeof(cmd_reply));
+	}
+
+	slot_free_req.slot_uid = ne_enclave->slot_uid;
+
+	rc = ne_do_request(pdev, SLOT_FREE,
+			   &slot_free_req, sizeof(slot_free_req),
+			   &cmd_reply, sizeof(cmd_reply));
+	if (rc < 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in slot free [rc=%d]\n", rc);
+
+		goto unlock_mutex;
+	}
+
+	ne_pci_dev_remove_enclave_entry(ne_enclave, ne_pci_dev);
+	ne_enclave_remove_all_mem_region_entries(ne_enclave);
+	ne_enclave_remove_all_vcpu_id_entries(ne_enclave);
+
+	mutex_unlock(&ne_enclave->enclave_info_mutex);
+	mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
+
+	kfree(ne_enclave);
+
+	return 0;
+
+unlock_mutex:
+	mutex_unlock(&ne_enclave->enclave_info_mutex);
+	mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
+
+	return rc;
+}
+
+/**
+ * ne_enclave_poll() - Poll functionality used for enclave out-of-band events.
+ * @file:	File associated with this poll function.
+ * @wait:	Poll table data structure.
+ *
+ * Context: Process context.
+ * Return:
+ * * Poll mask.
+ */
+static __poll_t ne_enclave_poll(struct file *file, poll_table *wait)
+{
+	__poll_t mask = 0;
+	struct ne_enclave *ne_enclave = file->private_data;
+
+	poll_wait(file, &ne_enclave->eventq, wait);
+
+	if (ne_enclave->has_event)
+		mask |= EPOLLHUP;
+
+	return mask;
+}
+
+static const struct file_operations ne_enclave_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= noop_llseek,
+	.poll		= ne_enclave_poll,
+	.unlocked_ioctl	= ne_enclave_ioctl,
+	.release	= ne_enclave_release,
+};
+
+/**
+ * ne_create_vm_ioctl() - Alloc slot to be associated with an enclave. Create
+ *			  enclave file descriptor to be further used for enclave
+ *			  resources handling e.g. memory regions and CPUs.
+ * @ne_pci_dev :	Private data associated with the PCI device.
+ * @slot_uid:		User pointer to store the generated unique slot id
+ *			associated with an enclave to.
+ *
+ * Context: Process context. This function is called with the ne_pci_dev enclave
+ *	    mutex held.
+ * Return:
+ * * Enclave fd on success.
+ * * Negative return value on failure.
+ */
+static int ne_create_vm_ioctl(struct ne_pci_dev *ne_pci_dev, u64 __user *slot_uid)
+{
+	struct ne_pci_dev_cmd_reply cmd_reply = {};
+	int enclave_fd = -1;
+	struct file *enclave_file = NULL;
+	unsigned int i = 0;
+	struct ne_enclave *ne_enclave = NULL;
+	struct pci_dev *pdev = ne_pci_dev->pdev;
+	int rc = -EINVAL;
+	struct slot_alloc_req slot_alloc_req = {};
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
+		if (!cpumask_empty(ne_cpu_pool.avail_threads_per_core[i]))
+			break;
+
+	if (i == ne_cpu_pool.nr_parent_vm_cores) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "No CPUs available in CPU pool\n");
+
+		mutex_unlock(&ne_cpu_pool.mutex);
+
+		return -NE_ERR_NO_CPUS_AVAIL_IN_POOL;
+	}
+
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	ne_enclave = kzalloc(sizeof(*ne_enclave), GFP_KERNEL);
+	if (!ne_enclave)
+		return -ENOMEM;
+
+	mutex_lock(&ne_cpu_pool.mutex);
+
+	ne_enclave->nr_parent_vm_cores = ne_cpu_pool.nr_parent_vm_cores;
+	ne_enclave->nr_threads_per_core = ne_cpu_pool.nr_threads_per_core;
+	ne_enclave->numa_node = ne_cpu_pool.numa_node;
+
+	mutex_unlock(&ne_cpu_pool.mutex);
+
+	ne_enclave->threads_per_core = kcalloc(ne_enclave->nr_parent_vm_cores,
+		sizeof(*ne_enclave->threads_per_core), GFP_KERNEL);
+	if (!ne_enclave->threads_per_core) {
+		rc = -ENOMEM;
+
+		goto free_ne_enclave;
+	}
+
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
+		if (!zalloc_cpumask_var(&ne_enclave->threads_per_core[i], GFP_KERNEL)) {
+			rc = -ENOMEM;
+
+			goto free_cpumask;
+		}
+
+	if (!zalloc_cpumask_var(&ne_enclave->vcpu_ids, GFP_KERNEL)) {
+		rc = -ENOMEM;
+
+		goto free_cpumask;
+	}
+
+	enclave_fd = get_unused_fd_flags(O_CLOEXEC);
+	if (enclave_fd < 0) {
+		rc = enclave_fd;
+
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in getting unused fd [rc=%d]\n", rc);
+
+		goto free_cpumask;
+	}
+
+	enclave_file = anon_inode_getfile("ne-vm", &ne_enclave_fops, ne_enclave, O_RDWR);
+	if (IS_ERR(enclave_file)) {
+		rc = PTR_ERR(enclave_file);
+
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in anon inode get file [rc=%d]\n", rc);
+
+		goto put_fd;
+	}
+
+	rc = ne_do_request(pdev, SLOT_ALLOC,
+			   &slot_alloc_req, sizeof(slot_alloc_req),
+			   &cmd_reply, sizeof(cmd_reply));
+	if (rc < 0) {
+		dev_err_ratelimited(ne_misc_dev.this_device,
+				    "Error in slot alloc [rc=%d]\n", rc);
+
+		goto put_file;
+	}
+
+	init_waitqueue_head(&ne_enclave->eventq);
+	ne_enclave->has_event = false;
+	mutex_init(&ne_enclave->enclave_info_mutex);
+	ne_enclave->max_mem_regions = cmd_reply.mem_regions;
+	INIT_LIST_HEAD(&ne_enclave->mem_regions_list);
+	ne_enclave->mm = current->mm;
+	ne_enclave->slot_uid = cmd_reply.slot_uid;
+	ne_enclave->state = NE_STATE_INIT;
+
+	list_add(&ne_enclave->enclave_list_entry, &ne_pci_dev->enclaves_list);
+
+	if (copy_to_user(slot_uid, &ne_enclave->slot_uid, sizeof(ne_enclave->slot_uid))) {
+		/*
+		 * As we're holding the only reference to 'enclave_file', fput()
+		 * will call ne_enclave_release() which will do a proper cleanup
+		 * of all so far allocated resources, leaving only the unused fd
+		 * for us to free.
+		 */
+		fput(enclave_file);
+		put_unused_fd(enclave_fd);
+
+		return -EFAULT;
+	}
+
+	fd_install(enclave_fd, enclave_file);
+
+	return enclave_fd;
+
+put_file:
+	fput(enclave_file);
+put_fd:
+	put_unused_fd(enclave_fd);
+free_cpumask:
+	free_cpumask_var(ne_enclave->vcpu_ids);
+	for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
+		free_cpumask_var(ne_enclave->threads_per_core[i]);
+	kfree(ne_enclave->threads_per_core);
+free_ne_enclave:
+	kfree(ne_enclave);
+
+	return rc;
+}
+
+/**
+ * ne_ioctl() - Ioctl function provided by the NE misc device.
+ * @file:	File associated with this ioctl function.
+ * @cmd:	The command that is set for the ioctl call.
+ * @arg:	The argument that is provided for the ioctl call.
+ *
+ * Context: Process context.
+ * Return:
+ * * Ioctl result (e.g. enclave file descriptor) on success.
+ * * Negative return value on failure.
+ */
+static long ne_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case NE_CREATE_VM: {
+		int enclave_fd = -1;
+		struct ne_pci_dev *ne_pci_dev = ne_devs.ne_pci_dev;
+		u64 __user *slot_uid = (void __user *)arg;
+
+		mutex_lock(&ne_pci_dev->enclaves_list_mutex);
+		enclave_fd = ne_create_vm_ioctl(ne_pci_dev, slot_uid);
+		mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
+
+		return enclave_fd;
+	}
+
+	default:
+		return -ENOTTY;
+	}
+
+	return 0;
+}
+
+static int __init ne_init(void)
+{
+	mutex_init(&ne_cpu_pool.mutex);
+
+	return pci_register_driver(&ne_pci_driver);
+}
+
+static void __exit ne_exit(void)
+{
+	pci_unregister_driver(&ne_pci_driver);
+
+	ne_teardown_cpu_pool();
+}
+
+module_init(ne_init);
+module_exit(ne_exit);
+
+MODULE_AUTHOR("Amazon.com, Inc. or its affiliates");
+MODULE_DESCRIPTION("Nitro Enclaves Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.h b/drivers/virt/nitro_enclaves/ne_misc_dev.h
new file mode 100644
index 000000000..2a4d2224b
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/ne_misc_dev.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+#ifndef _NE_MISC_DEV_H_
+#define _NE_MISC_DEV_H_
+
+#include <linux/cpumask.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+
+#include "ne_pci_dev.h"
+
+/**
+ * struct ne_mem_region - Entry in the enclave user space memory regions list.
+ * @mem_region_list_entry:	Entry in the list of enclave memory regions.
+ * @memory_size:		Size of the user space memory region.
+ * @nr_pages:			Number of pages that make up the memory region.
+ * @pages:			Pages that make up the user space memory region.
+ * @userspace_addr:		User space address of the memory region.
+ */
+struct ne_mem_region {
+	struct list_head	mem_region_list_entry;
+	u64			memory_size;
+	unsigned long		nr_pages;
+	struct page		**pages;
+	u64			userspace_addr;
+};
+
+/**
+ * struct ne_enclave - Per-enclave data used for enclave lifetime management.
+ * @enclave_info_mutex :	Mutex for accessing this internal state.
+ * @enclave_list_entry :	Entry in the list of created enclaves.
+ * @eventq:			Wait queue used for out-of-band event notifications
+ *				triggered from the PCI device event handler to
+ *				the enclave process via the poll function.
+ * @has_event:			Variable used to determine if the out-of-band event
+ *				was triggered.
+ * @max_mem_regions:		The maximum number of memory regions that can be
+ *				handled by the hypervisor.
+ * @mem_regions_list:		Enclave user space memory regions list.
+ * @mem_size:			Enclave memory size.
+ * @mm :			Enclave process abstraction mm data struct.
+ * @nr_mem_regions:		Number of memory regions associated with the enclave.
+ * @nr_parent_vm_cores :	The size of the threads per core array. The
+ *				total number of CPU cores available on the
+ *				parent / primary VM.
+ * @nr_threads_per_core:	The number of threads that a full CPU core has.
+ * @nr_vcpus:			Number of vcpus associated with the enclave.
+ * @numa_node:			NUMA node of the enclave memory and CPUs.
+ * @slot_uid:			Slot unique id mapped to the enclave.
+ * @state:			Enclave state, updated during enclave lifetime.
+ * @threads_per_core:		Enclave full CPU cores array, indexed by core id,
+ *				consisting of cpumasks with all their threads.
+ *				Full CPU cores are taken from the NE CPU pool
+ *				and are available to the enclave.
+ * @vcpu_ids:			Cpumask of the vCPUs that are set for the enclave.
+ */
+struct ne_enclave {
+	struct mutex		enclave_info_mutex;
+	struct list_head	enclave_list_entry;
+	wait_queue_head_t	eventq;
+	bool			has_event;
+	u64			max_mem_regions;
+	struct list_head	mem_regions_list;
+	u64			mem_size;
+	struct mm_struct	*mm;
+	unsigned int		nr_mem_regions;
+	unsigned int		nr_parent_vm_cores;
+	unsigned int		nr_threads_per_core;
+	unsigned int		nr_vcpus;
+	int			numa_node;
+	u64			slot_uid;
+	u16			state;
+	cpumask_var_t		*threads_per_core;
+	cpumask_var_t		vcpu_ids;
+};
+
+/**
+ * enum ne_state - States available for an enclave.
+ * @NE_STATE_INIT:	The enclave has not been started yet.
+ * @NE_STATE_RUNNING:	The enclave was started and is running as expected.
+ * @NE_STATE_STOPPED:	The enclave exited without userspace interaction.
+ */
+enum ne_state {
+	NE_STATE_INIT		= 0,
+	NE_STATE_RUNNING	= 2,
+	NE_STATE_STOPPED	= U16_MAX,
+};
+
+/**
+ * struct ne_devs - Data structure to keep refs to the NE misc and PCI devices.
+ * @ne_misc_dev:	Nitro Enclaves misc device.
+ * @ne_pci_dev :	Nitro Enclaves PCI device.
+ */
+struct ne_devs {
+	struct miscdevice	*ne_misc_dev;
+	struct ne_pci_dev	*ne_pci_dev;
+};
+
+/* Nitro Enclaves (NE) data structure for keeping refs to the NE misc and PCI devices. */
+extern struct ne_devs ne_devs;
+
+#endif /* _NE_MISC_DEV_H_ */
diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c b/drivers/virt/nitro_enclaves/ne_pci_dev.c
new file mode 100644
index 000000000..b9c1de41e
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c
@@ -0,0 +1,625 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+/**
+ * DOC: Nitro Enclaves (NE) PCI device driver.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/nitro_enclaves.h>
+#include <linux/pci.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+
+#include "ne_misc_dev.h"
+#include "ne_pci_dev.h"
+
+/**
+ * NE_DEFAULT_TIMEOUT_MSECS - Default timeout to wait for a reply from
+ *			      the NE PCI device.
+ */
+#define NE_DEFAULT_TIMEOUT_MSECS	(120000) /* 120 sec */
+
+static const struct pci_device_id ne_pci_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, PCI_DEVICE_ID_NE) },
+	{ 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, ne_pci_ids);
+
+/**
+ * ne_submit_request() - Submit command request to the PCI device based on the
+ *			 command type.
+ * @pdev:		PCI device to send the command to.
+ * @cmd_type:		Command type of the request sent to the PCI device.
+ * @cmd_request:	Command request payload.
+ * @cmd_request_size:	Size of the command request payload.
+ *
+ * Context: Process context. This function is called with the ne_pci_dev mutex held.
+ */
+static void ne_submit_request(struct pci_dev *pdev, enum ne_pci_dev_cmd_type cmd_type,
+			      void *cmd_request, size_t cmd_request_size)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	memcpy_toio(ne_pci_dev->iomem_base + NE_SEND_DATA, cmd_request, cmd_request_size);
+
+	iowrite32(cmd_type, ne_pci_dev->iomem_base + NE_COMMAND);
+}
+
+/**
+ * ne_retrieve_reply() - Retrieve reply from the PCI device.
+ * @pdev:		PCI device to receive the reply from.
+ * @cmd_reply:		Command reply payload.
+ * @cmd_reply_size:	Size of the command reply payload.
+ *
+ * Context: Process context. This function is called with the ne_pci_dev mutex held.
+ */
+static void ne_retrieve_reply(struct pci_dev *pdev, struct ne_pci_dev_cmd_reply *cmd_reply,
+			      size_t cmd_reply_size)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	memcpy_fromio(cmd_reply, ne_pci_dev->iomem_base + NE_RECV_DATA, cmd_reply_size);
+}
+
+/**
+ * ne_wait_for_reply() - Wait for a reply of a PCI device command.
+ * @pdev:	PCI device for which a reply is waited.
+ *
+ * Context: Process context. This function is called with the ne_pci_dev mutex held.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_wait_for_reply(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	int rc = -EINVAL;
+
+	/*
+	 * TODO: Update to _interruptible and handle interrupted wait event
+	 * e.g. -ERESTARTSYS, incoming signals + update timeout, if needed.
+	 */
+	rc = wait_event_timeout(ne_pci_dev->cmd_reply_wait_q,
+				atomic_read(&ne_pci_dev->cmd_reply_avail) != 0,
+				msecs_to_jiffies(NE_DEFAULT_TIMEOUT_MSECS));
+	if (!rc)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+int ne_do_request(struct pci_dev *pdev, enum ne_pci_dev_cmd_type cmd_type,
+		  void *cmd_request, size_t cmd_request_size,
+		  struct ne_pci_dev_cmd_reply *cmd_reply, size_t cmd_reply_size)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	int rc = -EINVAL;
+
+	if (cmd_type <= INVALID_CMD || cmd_type >= MAX_CMD) {
+		dev_err_ratelimited(&pdev->dev, "Invalid cmd type=%u\n", cmd_type);
+
+		return -EINVAL;
+	}
+
+	if (!cmd_request) {
+		dev_err_ratelimited(&pdev->dev, "Null cmd request for cmd type=%u\n",
+				    cmd_type);
+
+		return -EINVAL;
+	}
+
+	if (cmd_request_size > NE_SEND_DATA_SIZE) {
+		dev_err_ratelimited(&pdev->dev, "Invalid req size=%zu for cmd type=%u\n",
+				    cmd_request_size, cmd_type);
+
+		return -EINVAL;
+	}
+
+	if (!cmd_reply) {
+		dev_err_ratelimited(&pdev->dev, "Null cmd reply for cmd type=%u\n",
+				    cmd_type);
+
+		return -EINVAL;
+	}
+
+	if (cmd_reply_size > NE_RECV_DATA_SIZE) {
+		dev_err_ratelimited(&pdev->dev, "Invalid reply size=%zu for cmd type=%u\n",
+				    cmd_reply_size, cmd_type);
+
+		return -EINVAL;
+	}
+
+	/*
+	 * Use this mutex so that the PCI device handles one command request at
+	 * a time.
+	 */
+	mutex_lock(&ne_pci_dev->pci_dev_mutex);
+
+	atomic_set(&ne_pci_dev->cmd_reply_avail, 0);
+
+	ne_submit_request(pdev, cmd_type, cmd_request, cmd_request_size);
+
+	rc = ne_wait_for_reply(pdev);
+	if (rc < 0) {
+		dev_err_ratelimited(&pdev->dev, "Error in wait for reply for cmd type=%u [rc=%d]\n",
+				    cmd_type, rc);
+
+		goto unlock_mutex;
+	}
+
+	ne_retrieve_reply(pdev, cmd_reply, cmd_reply_size);
+
+	atomic_set(&ne_pci_dev->cmd_reply_avail, 0);
+
+	if (cmd_reply->rc < 0) {
+		rc = cmd_reply->rc;
+
+		dev_err_ratelimited(&pdev->dev, "Error in cmd process logic, cmd type=%u [rc=%d]\n",
+				    cmd_type, rc);
+
+		goto unlock_mutex;
+	}
+
+	rc = 0;
+
+unlock_mutex:
+	mutex_unlock(&ne_pci_dev->pci_dev_mutex);
+
+	return rc;
+}
+
+/**
+ * ne_reply_handler() - Interrupt handler for retrieving a reply matching a
+ *			request sent to the PCI device for enclave lifetime
+ *			management.
+ * @irq:	Received interrupt for a reply sent by the PCI device.
+ * @args:	PCI device private data structure.
+ *
+ * Context: Interrupt context.
+ * Return:
+ * * IRQ_HANDLED on handled interrupt.
+ */
+static irqreturn_t ne_reply_handler(int irq, void *args)
+{
+	struct ne_pci_dev *ne_pci_dev = (struct ne_pci_dev *)args;
+
+	atomic_set(&ne_pci_dev->cmd_reply_avail, 1);
+
+	/* TODO: Update to _interruptible. */
+	wake_up(&ne_pci_dev->cmd_reply_wait_q);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ne_event_work_handler() - Work queue handler for notifying enclaves on a
+ *			     state change received by the event interrupt
+ *			     handler.
+ * @work:	Item containing the NE PCI device for which an out-of-band event
+ *		was issued.
+ *
+ * An out-of-band event is being issued by the Nitro Hypervisor when at least
+ * one enclave is changing state without client interaction.
+ *
+ * Context: Work queue context.
+ */
+static void ne_event_work_handler(struct work_struct *work)
+{
+	struct ne_pci_dev_cmd_reply cmd_reply = {};
+	struct ne_enclave *ne_enclave = NULL;
+	struct ne_pci_dev *ne_pci_dev =
+		container_of(work, struct ne_pci_dev, notify_work);
+	struct pci_dev *pdev = ne_pci_dev->pdev;
+	int rc = -EINVAL;
+	struct slot_info_req slot_info_req = {};
+
+	mutex_lock(&ne_pci_dev->enclaves_list_mutex);
+
+	/*
+	 * Iterate over all enclaves registered for the Nitro Enclaves
+	 * PCI device and determine for which enclave(s) the out-of-band event
+	 * is corresponding to.
+	 */
+	list_for_each_entry(ne_enclave, &ne_pci_dev->enclaves_list, enclave_list_entry) {
+		mutex_lock(&ne_enclave->enclave_info_mutex);
+
+		/*
+		 * Enclaves that were never started cannot receive out-of-band
+		 * events.
+		 */
+		if (ne_enclave->state != NE_STATE_RUNNING)
+			goto unlock;
+
+		slot_info_req.slot_uid = ne_enclave->slot_uid;
+
+		rc = ne_do_request(pdev, SLOT_INFO,
+				   &slot_info_req, sizeof(slot_info_req),
+				   &cmd_reply, sizeof(cmd_reply));
+		if (rc < 0)
+			dev_err(&pdev->dev, "Error in slot info [rc=%d]\n", rc);
+
+		/* Notify enclave process that the enclave state changed. */
+		if (ne_enclave->state != cmd_reply.state) {
+			ne_enclave->state = cmd_reply.state;
+
+			ne_enclave->has_event = true;
+
+			wake_up_interruptible(&ne_enclave->eventq);
+		}
+
+unlock:
+		 mutex_unlock(&ne_enclave->enclave_info_mutex);
+	}
+
+	mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
+}
+
+/**
+ * ne_event_handler() - Interrupt handler for PCI device out-of-band events.
+ *			This interrupt does not supply any data in the MMIO
+ *			region. It notifies a change in the state of any of
+ *			the launched enclaves.
+ * @irq:	Received interrupt for an out-of-band event.
+ * @args:	PCI device private data structure.
+ *
+ * Context: Interrupt context.
+ * Return:
+ * * IRQ_HANDLED on handled interrupt.
+ */
+static irqreturn_t ne_event_handler(int irq, void *args)
+{
+	struct ne_pci_dev *ne_pci_dev = (struct ne_pci_dev *)args;
+
+	queue_work(ne_pci_dev->event_wq, &ne_pci_dev->notify_work);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * ne_setup_msix() - Setup MSI-X vectors for the PCI device.
+ * @pdev:	PCI device to setup the MSI-X for.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_setup_msix(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	int nr_vecs = 0;
+	int rc = -EINVAL;
+
+	nr_vecs = pci_msix_vec_count(pdev);
+	if (nr_vecs < 0) {
+		rc = nr_vecs;
+
+		dev_err(&pdev->dev, "Error in getting vec count [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in alloc MSI-X vecs [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	/*
+	 * This IRQ gets triggered every time the PCI device responds to a
+	 * command request. The reply is then retrieved, reading from the MMIO
+	 * space of the PCI device.
+	 */
+	rc = request_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_reply_handler,
+			 0, "enclave_cmd", ne_pci_dev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in request irq reply [rc=%d]\n", rc);
+
+		goto free_irq_vectors;
+	}
+
+	ne_pci_dev->event_wq = create_singlethread_workqueue("ne_pci_dev_wq");
+	if (!ne_pci_dev->event_wq) {
+		rc = -ENOMEM;
+
+		dev_err(&pdev->dev, "Cannot get wq for dev events [rc=%d]\n", rc);
+
+		goto free_reply_irq_vec;
+	}
+
+	INIT_WORK(&ne_pci_dev->notify_work, ne_event_work_handler);
+
+	/*
+	 * This IRQ gets triggered every time any enclave's state changes. Its
+	 * handler then scans for the changes and propagates them to the user
+	 * space.
+	 */
+	rc = request_irq(pci_irq_vector(pdev, NE_VEC_EVENT), ne_event_handler,
+			 0, "enclave_evt", ne_pci_dev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in request irq event [rc=%d]\n", rc);
+
+		goto destroy_wq;
+	}
+
+	return 0;
+
+destroy_wq:
+	destroy_workqueue(ne_pci_dev->event_wq);
+free_reply_irq_vec:
+	free_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_pci_dev);
+free_irq_vectors:
+	pci_free_irq_vectors(pdev);
+
+	return rc;
+}
+
+/**
+ * ne_teardown_msix() - Teardown MSI-X vectors for the PCI device.
+ * @pdev:	PCI device to teardown the MSI-X for.
+ *
+ * Context: Process context.
+ */
+static void ne_teardown_msix(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	free_irq(pci_irq_vector(pdev, NE_VEC_EVENT), ne_pci_dev);
+
+	flush_work(&ne_pci_dev->notify_work);
+	flush_workqueue(ne_pci_dev->event_wq);
+	destroy_workqueue(ne_pci_dev->event_wq);
+
+	free_irq(pci_irq_vector(pdev, NE_VEC_REPLY), ne_pci_dev);
+
+	pci_free_irq_vectors(pdev);
+}
+
+/**
+ * ne_pci_dev_enable() - Select the PCI device version and enable it.
+ * @pdev:	PCI device to select version for and then enable.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_pci_dev_enable(struct pci_dev *pdev)
+{
+	u8 dev_enable_reply = 0;
+	u16 dev_version_reply = 0;
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	iowrite16(NE_VERSION_MAX, ne_pci_dev->iomem_base + NE_VERSION);
+
+	dev_version_reply = ioread16(ne_pci_dev->iomem_base + NE_VERSION);
+	if (dev_version_reply != NE_VERSION_MAX) {
+		dev_err(&pdev->dev, "Error in pci dev version cmd\n");
+
+		return -EIO;
+	}
+
+	iowrite8(NE_ENABLE_ON, ne_pci_dev->iomem_base + NE_ENABLE);
+
+	dev_enable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+	if (dev_enable_reply != NE_ENABLE_ON) {
+		dev_err(&pdev->dev, "Error in pci dev enable cmd\n");
+
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_pci_dev_disable() - Disable the PCI device.
+ * @pdev:	PCI device to disable.
+ *
+ * Context: Process context.
+ */
+static void ne_pci_dev_disable(struct pci_dev *pdev)
+{
+	u8 dev_disable_reply = 0;
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	const unsigned int sleep_time = 10; /* 10 ms */
+	unsigned int sleep_time_count = 0;
+
+	iowrite8(NE_ENABLE_OFF, ne_pci_dev->iomem_base + NE_ENABLE);
+
+	/*
+	 * Check for NE_ENABLE_OFF in a loop, to handle cases when the device
+	 * state is not immediately set to disabled and going through a
+	 * transitory state of disabling.
+	 */
+	while (sleep_time_count < NE_DEFAULT_TIMEOUT_MSECS) {
+		dev_disable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+		if (dev_disable_reply == NE_ENABLE_OFF)
+			return;
+
+		msleep_interruptible(sleep_time);
+		sleep_time_count += sleep_time;
+	}
+
+	dev_disable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+	if (dev_disable_reply != NE_ENABLE_OFF)
+		dev_err(&pdev->dev, "Error in pci dev disable cmd\n");
+}
+
+/**
+ * ne_pci_probe() - Probe function for the NE PCI device.
+ * @pdev:	PCI device to match with the NE PCI driver.
+ * @id :	PCI device id table associated with the NE PCI driver.
+ *
+ * Context: Process context.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+static int ne_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct ne_pci_dev *ne_pci_dev = NULL;
+	int rc = -EINVAL;
+
+	ne_pci_dev = kzalloc(sizeof(*ne_pci_dev), GFP_KERNEL);
+	if (!ne_pci_dev)
+		return -ENOMEM;
+
+	rc = pci_enable_device(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci dev enable [rc=%d]\n", rc);
+
+		goto free_ne_pci_dev;
+	}
+
+	rc = pci_request_regions_exclusive(pdev, "nitro_enclaves");
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci request regions [rc=%d]\n", rc);
+
+		goto disable_pci_dev;
+	}
+
+	ne_pci_dev->iomem_base = pci_iomap(pdev, PCI_BAR_NE, 0);
+	if (!ne_pci_dev->iomem_base) {
+		rc = -ENOMEM;
+
+		dev_err(&pdev->dev, "Error in pci iomap [rc=%d]\n", rc);
+
+		goto release_pci_regions;
+	}
+
+	pci_set_drvdata(pdev, ne_pci_dev);
+
+	rc = ne_setup_msix(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci dev msix setup [rc=%d]\n", rc);
+
+		goto iounmap_pci_bar;
+	}
+
+	ne_pci_dev_disable(pdev);
+
+	rc = ne_pci_dev_enable(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in ne_pci_dev enable [rc=%d]\n", rc);
+
+		goto teardown_msix;
+	}
+
+	atomic_set(&ne_pci_dev->cmd_reply_avail, 0);
+	init_waitqueue_head(&ne_pci_dev->cmd_reply_wait_q);
+	INIT_LIST_HEAD(&ne_pci_dev->enclaves_list);
+	mutex_init(&ne_pci_dev->enclaves_list_mutex);
+	mutex_init(&ne_pci_dev->pci_dev_mutex);
+	ne_pci_dev->pdev = pdev;
+
+	ne_devs.ne_pci_dev = ne_pci_dev;
+
+	rc = misc_register(ne_devs.ne_misc_dev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in misc dev register [rc=%d]\n", rc);
+
+		goto disable_ne_pci_dev;
+	}
+
+	return 0;
+
+disable_ne_pci_dev:
+	ne_devs.ne_pci_dev = NULL;
+	ne_pci_dev_disable(pdev);
+teardown_msix:
+	ne_teardown_msix(pdev);
+iounmap_pci_bar:
+	pci_set_drvdata(pdev, NULL);
+	pci_iounmap(pdev, ne_pci_dev->iomem_base);
+release_pci_regions:
+	pci_release_regions(pdev);
+disable_pci_dev:
+	pci_disable_device(pdev);
+free_ne_pci_dev:
+	kfree(ne_pci_dev);
+
+	return rc;
+}
+
+/**
+ * ne_pci_remove() - Remove function for the NE PCI device.
+ * @pdev:	PCI device associated with the NE PCI driver.
+ *
+ * Context: Process context.
+ */
+static void ne_pci_remove(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	misc_deregister(ne_devs.ne_misc_dev);
+
+	ne_devs.ne_pci_dev = NULL;
+
+	ne_pci_dev_disable(pdev);
+
+	ne_teardown_msix(pdev);
+
+	pci_set_drvdata(pdev, NULL);
+
+	pci_iounmap(pdev, ne_pci_dev->iomem_base);
+
+	pci_release_regions(pdev);
+
+	pci_disable_device(pdev);
+
+	kfree(ne_pci_dev);
+}
+
+/**
+ * ne_pci_shutdown() - Shutdown function for the NE PCI device.
+ * @pdev:	PCI device associated with the NE PCI driver.
+ *
+ * Context: Process context.
+ */
+static void ne_pci_shutdown(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	if (!ne_pci_dev)
+		return;
+
+	misc_deregister(ne_devs.ne_misc_dev);
+
+	ne_devs.ne_pci_dev = NULL;
+
+	ne_pci_dev_disable(pdev);
+
+	ne_teardown_msix(pdev);
+
+	pci_set_drvdata(pdev, NULL);
+
+	pci_iounmap(pdev, ne_pci_dev->iomem_base);
+
+	pci_release_regions(pdev);
+
+	pci_disable_device(pdev);
+
+	kfree(ne_pci_dev);
+}
+
+/*
+ * TODO: Add suspend / resume functions for power management w/ CONFIG_PM, if
+ * needed.
+ */
+/* NE PCI device driver. */
+struct pci_driver ne_pci_driver = {
+	.name		= "nitro_enclaves",
+	.id_table	= ne_pci_ids,
+	.probe		= ne_pci_probe,
+	.remove		= ne_pci_remove,
+	.shutdown	= ne_pci_shutdown,
+};
diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.h b/drivers/virt/nitro_enclaves/ne_pci_dev.h
new file mode 100644
index 000000000..8bfbc6607
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/ne_pci_dev.h
@@ -0,0 +1,327 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+#ifndef _NE_PCI_DEV_H_
+#define _NE_PCI_DEV_H_
+
+#include <linux/atomic.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/wait.h>
+
+/**
+ * DOC: Nitro Enclaves (NE) PCI device
+ */
+
+/**
+ * PCI_DEVICE_ID_NE - Nitro Enclaves PCI device id.
+ */
+#define PCI_DEVICE_ID_NE	(0xe4c1)
+/**
+ * PCI_BAR_NE - Nitro Enclaves PCI device MMIO BAR.
+ */
+#define PCI_BAR_NE		(0x03)
+
+/**
+ * DOC: Device registers in the NE PCI device MMIO BAR
+ */
+
+/**
+ * NE_ENABLE - (1 byte) Register to notify the device that the driver is using
+ *	       it (Read/Write).
+ */
+#define NE_ENABLE		(0x0000)
+#define NE_ENABLE_OFF		(0x00)
+#define NE_ENABLE_ON		(0x01)
+
+/**
+ * NE_VERSION - (2 bytes) Register to select the device run-time version
+ *		(Read/Write).
+ */
+#define NE_VERSION		(0x0002)
+#define NE_VERSION_MAX		(0x0001)
+
+/**
+ * NE_COMMAND - (4 bytes) Register to notify the device what command was
+ *		requested (Write-Only).
+ */
+#define NE_COMMAND		(0x0004)
+
+/**
+ * NE_EVTCNT - (4 bytes) Register to notify the driver that a reply or a device
+ *	       event is available (Read-Only):
+ *	       - Lower half  - command reply counter
+ *	       - Higher half - out-of-band device event counter
+ */
+#define NE_EVTCNT		(0x000c)
+#define NE_EVTCNT_REPLY_SHIFT	(0)
+#define NE_EVTCNT_REPLY_MASK	(0x0000ffff)
+#define NE_EVTCNT_REPLY(cnt)	(((cnt) & NE_EVTCNT_REPLY_MASK) >> \
+				NE_EVTCNT_REPLY_SHIFT)
+#define NE_EVTCNT_EVENT_SHIFT	(16)
+#define NE_EVTCNT_EVENT_MASK	(0xffff0000)
+#define NE_EVTCNT_EVENT(cnt)	(((cnt) & NE_EVTCNT_EVENT_MASK) >> \
+				NE_EVTCNT_EVENT_SHIFT)
+
+/**
+ * NE_SEND_DATA - (240 bytes) Buffer for sending the command request payload
+ *		  (Read/Write).
+ */
+#define NE_SEND_DATA		(0x0010)
+
+/**
+ * NE_RECV_DATA - (240 bytes) Buffer for receiving the command reply payload
+ *		  (Read-Only).
+ */
+#define NE_RECV_DATA		(0x0100)
+
+/**
+ * DOC: Device MMIO buffer sizes
+ */
+
+/**
+ * NE_SEND_DATA_SIZE / NE_RECV_DATA_SIZE - 240 bytes for send / recv buffer.
+ */
+#define NE_SEND_DATA_SIZE	(240)
+#define NE_RECV_DATA_SIZE	(240)
+
+/**
+ * DOC: MSI-X interrupt vectors
+ */
+
+/**
+ * NE_VEC_REPLY - MSI-X vector used for command reply notification.
+ */
+#define NE_VEC_REPLY		(0)
+
+/**
+ * NE_VEC_EVENT - MSI-X vector used for out-of-band events e.g. enclave crash.
+ */
+#define NE_VEC_EVENT		(1)
+
+/**
+ * enum ne_pci_dev_cmd_type - Device command types.
+ * @INVALID_CMD:		Invalid command.
+ * @ENCLAVE_START:		Start an enclave, after setting its resources.
+ * @ENCLAVE_GET_SLOT:		Get the slot uid of an enclave.
+ * @ENCLAVE_STOP:		Terminate an enclave.
+ * @SLOT_ALLOC :		Allocate a slot for an enclave.
+ * @SLOT_FREE:			Free the slot allocated for an enclave
+ * @SLOT_ADD_MEM:		Add a memory region to an enclave slot.
+ * @SLOT_ADD_VCPU:		Add a vCPU to an enclave slot.
+ * @SLOT_COUNT :		Get the number of allocated slots.
+ * @NEXT_SLOT:			Get the next slot in the list of allocated slots.
+ * @SLOT_INFO:			Get the info for a slot e.g. slot uid, vCPUs count.
+ * @SLOT_ADD_BULK_VCPUS:	Add a number of vCPUs, not providing CPU ids.
+ * @MAX_CMD:			A gatekeeper for max possible command type.
+ */
+enum ne_pci_dev_cmd_type {
+	INVALID_CMD		= 0,
+	ENCLAVE_START		= 1,
+	ENCLAVE_GET_SLOT	= 2,
+	ENCLAVE_STOP		= 3,
+	SLOT_ALLOC		= 4,
+	SLOT_FREE		= 5,
+	SLOT_ADD_MEM		= 6,
+	SLOT_ADD_VCPU		= 7,
+	SLOT_COUNT		= 8,
+	NEXT_SLOT		= 9,
+	SLOT_INFO		= 10,
+	SLOT_ADD_BULK_VCPUS	= 11,
+	MAX_CMD,
+};
+
+/**
+ * DOC: Device commands - payload structure for requests and replies.
+ */
+
+/**
+ * struct enclave_start_req - ENCLAVE_START request.
+ * @slot_uid:		Slot unique id mapped to the enclave to start.
+ * @enclave_cid:	Context ID (CID) for the enclave vsock device.
+ *			If 0, CID is autogenerated.
+ * @flags:		Flags for the enclave to start with (e.g. debug mode).
+ */
+struct enclave_start_req {
+	u64	slot_uid;
+	u64	enclave_cid;
+	u64	flags;
+};
+
+/**
+ * struct enclave_get_slot_req - ENCLAVE_GET_SLOT request.
+ * @enclave_cid:	Context ID (CID) for the enclave vsock device.
+ */
+struct enclave_get_slot_req {
+	u64	enclave_cid;
+};
+
+/**
+ * struct enclave_stop_req - ENCLAVE_STOP request.
+ * @slot_uid:	Slot unique id mapped to the enclave to stop.
+ */
+struct enclave_stop_req {
+	u64	slot_uid;
+};
+
+/**
+ * struct slot_alloc_req - SLOT_ALLOC request.
+ * @unused:	In order to avoid weird sizeof edge cases.
+ */
+struct slot_alloc_req {
+	u8	unused;
+};
+
+/**
+ * struct slot_free_req - SLOT_FREE request.
+ * @slot_uid:	Slot unique id mapped to the slot to free.
+ */
+struct slot_free_req {
+	u64	slot_uid;
+};
+
+/* TODO: Add flags field to the request to add memory region. */
+/**
+ * struct slot_add_mem_req - SLOT_ADD_MEM request.
+ * @slot_uid:	Slot unique id mapped to the slot to add the memory region to.
+ * @paddr:	Physical address of the memory region to add to the slot.
+ * @size:	Memory size, in bytes, of the memory region to add to the slot.
+ */
+struct slot_add_mem_req {
+	u64	slot_uid;
+	u64	paddr;
+	u64	size;
+};
+
+/**
+ * struct slot_add_vcpu_req - SLOT_ADD_VCPU request.
+ * @slot_uid:	Slot unique id mapped to the slot to add the vCPU to.
+ * @vcpu_id:	vCPU ID of the CPU to add to the enclave.
+ * @padding:	Padding for the overall data structure.
+ */
+struct slot_add_vcpu_req {
+	u64	slot_uid;
+	u32	vcpu_id;
+	u8	padding[4];
+};
+
+/**
+ * struct slot_count_req - SLOT_COUNT request.
+ * @unused:	In order to avoid weird sizeof edge cases.
+ */
+struct slot_count_req {
+	u8	unused;
+};
+
+/**
+ * struct next_slot_req - NEXT_SLOT request.
+ * @slot_uid:	Slot unique id of the next slot in the iteration.
+ */
+struct next_slot_req {
+	u64	slot_uid;
+};
+
+/**
+ * struct slot_info_req - SLOT_INFO request.
+ * @slot_uid:	Slot unique id mapped to the slot to get information about.
+ */
+struct slot_info_req {
+	u64	slot_uid;
+};
+
+/**
+ * struct slot_add_bulk_vcpus_req - SLOT_ADD_BULK_VCPUS request.
+ * @slot_uid:	Slot unique id mapped to the slot to add vCPUs to.
+ * @nr_vcpus:	Number of vCPUs to add to the slot.
+ */
+struct slot_add_bulk_vcpus_req {
+	u64	slot_uid;
+	u64	nr_vcpus;
+};
+
+/**
+ * struct ne_pci_dev_cmd_reply - NE PCI device command reply.
+ * @rc :		Return code of the logic that processed the request.
+ * @padding0:		Padding for the overall data structure.
+ * @slot_uid:		Valid for all commands except SLOT_COUNT.
+ * @enclave_cid:	Valid for ENCLAVE_START command.
+ * @slot_count :	Valid for SLOT_COUNT command.
+ * @mem_regions:	Valid for SLOT_ALLOC and SLOT_INFO commands.
+ * @mem_size:		Valid for SLOT_INFO command.
+ * @nr_vcpus:		Valid for SLOT_INFO command.
+ * @flags:		Valid for SLOT_INFO command.
+ * @state:		Valid for SLOT_INFO command.
+ * @padding1:		Padding for the overall data structure.
+ */
+struct ne_pci_dev_cmd_reply {
+	s32	rc;
+	u8	padding0[4];
+	u64	slot_uid;
+	u64	enclave_cid;
+	u64	slot_count;
+	u64	mem_regions;
+	u64	mem_size;
+	u64	nr_vcpus;
+	u64	flags;
+	u16	state;
+	u8	padding1[6];
+};
+
+/**
+ * struct ne_pci_dev - Nitro Enclaves (NE) PCI device.
+ * @cmd_reply_avail:		Variable set if a reply has been sent by the
+ *				PCI device.
+ * @cmd_reply_wait_q:		Wait queue for handling command reply from the
+ *				PCI device.
+ * @enclaves_list:		List of the enclaves managed by the PCI device.
+ * @enclaves_list_mutex:	Mutex for accessing the list of enclaves.
+ * @event_wq:			Work queue for handling out-of-band events
+ *				triggered by the Nitro Hypervisor which require
+ *				enclave state scanning and propagation to the
+ *				enclave process.
+ * @iomem_base :		MMIO region of the PCI device.
+ * @notify_work:		Work item for every received out-of-band event.
+ * @pci_dev_mutex:		Mutex for accessing the PCI device MMIO space.
+ * @pdev:			PCI device data structure.
+ */
+struct ne_pci_dev {
+	atomic_t		cmd_reply_avail;
+	wait_queue_head_t	cmd_reply_wait_q;
+	struct list_head	enclaves_list;
+	struct mutex		enclaves_list_mutex;
+	struct workqueue_struct	*event_wq;
+	void __iomem		*iomem_base;
+	struct work_struct	notify_work;
+	struct mutex		pci_dev_mutex;
+	struct pci_dev		*pdev;
+};
+
+/**
+ * ne_do_request() - Submit command request to the PCI device based on the command
+ *		     type and retrieve the associated reply.
+ * @pdev:		PCI device to send the command to and receive the reply from.
+ * @cmd_type:		Command type of the request sent to the PCI device.
+ * @cmd_request:	Command request payload.
+ * @cmd_request_size:	Size of the command request payload.
+ * @cmd_reply:		Command reply payload.
+ * @cmd_reply_size:	Size of the command reply payload.
+ *
+ * Context: Process context. This function uses the ne_pci_dev mutex to handle
+ *	    one command at a time.
+ * Return:
+ * * 0 on success.
+ * * Negative return value on failure.
+ */
+int ne_do_request(struct pci_dev *pdev, enum ne_pci_dev_cmd_type cmd_type,
+		  void *cmd_request, size_t cmd_request_size,
+		  struct ne_pci_dev_cmd_reply *cmd_reply,
+		  size_t cmd_reply_size);
+
+/* Nitro Enclaves (NE) PCI device driver */
+extern struct pci_driver ne_pci_driver;
+
+#endif /* _NE_PCI_DEV_H_ */
diff --git a/drivers/virt/vboxguest/Kconfig b/drivers/virt/vboxguest/Kconfig
new file mode 100644
index 000000000..cc329887b
--- /dev/null
+++ b/drivers/virt/vboxguest/Kconfig
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config VBOXGUEST
+	tristate "Virtual Box Guest integration support"
+	depends on X86 && PCI && INPUT
+	help
+	  This is a driver for the Virtual Box Guest PCI device used in
+	  Virtual Box virtual machines. Enabling this driver will add
+	  support for Virtual Box Guest integration features such as
+	  copy-and-paste, seamless mode and OpenGL pass-through.
+
+	  This driver also offers vboxguest IPC functionality which is needed
+	  for the vboxfs driver which offers folder sharing support.
+
+	  If you enable this driver you should also enable the VBOXVIDEO option.
+
+	  Although it is possible to build this module in, it is advised
+	  to build this driver as a module, so that it can be updated
+	  independently of the kernel. Select M to build this driver as a
+	  module.
diff --git a/drivers/virt/vboxguest/Makefile b/drivers/virt/vboxguest/Makefile
new file mode 100644
index 000000000..804279216
--- /dev/null
+++ b/drivers/virt/vboxguest/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vboxguest-y := vboxguest_linux.o vboxguest_core.o vboxguest_utils.o
+
+obj-$(CONFIG_VBOXGUEST) += vboxguest.o
diff --git a/drivers/virt/vboxguest/vboxguest_core.c b/drivers/virt/vboxguest/vboxguest_core.c
new file mode 100644
index 000000000..0b43efdde
--- /dev/null
+++ b/drivers/virt/vboxguest/vboxguest_core.c
@@ -0,0 +1,1826 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
+/*
+ * vboxguest core guest-device handling code, VBoxGuest.cpp in upstream svn.
+ *
+ * Copyright (C) 2007-2016 Oracle Corporation
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/vbox_err.h>
+#include <linux/vbox_utils.h>
+#include <linux/vmalloc.h>
+#include "vboxguest_core.h"
+#include "vboxguest_version.h"
+
+/* Get the pointer to the first HGCM parameter. */
+#define VBG_IOCTL_HGCM_CALL_PARMS(a) \
+	((struct vmmdev_hgcm_function_parameter *)( \
+		(u8 *)(a) + sizeof(struct vbg_ioctl_hgcm_call)))
+/* Get the pointer to the first HGCM parameter in a 32-bit request. */
+#define VBG_IOCTL_HGCM_CALL_PARMS32(a) \
+	((struct vmmdev_hgcm_function_parameter32 *)( \
+		(u8 *)(a) + sizeof(struct vbg_ioctl_hgcm_call)))
+
+#define GUEST_MAPPINGS_TRIES	5
+
+#define VBG_KERNEL_REQUEST \
+	(VMMDEV_REQUESTOR_KERNEL | VMMDEV_REQUESTOR_USR_DRV | \
+	 VMMDEV_REQUESTOR_CON_DONT_KNOW | VMMDEV_REQUESTOR_TRUST_NOT_GIVEN)
+
+/**
+ * Reserves memory in which the VMM can relocate any guest mappings
+ * that are floating around.
+ *
+ * This operation is a little bit tricky since the VMM might not accept
+ * just any address because of address clashes between the three contexts
+ * it operates in, so we try several times.
+ *
+ * Failure to reserve the guest mappings is ignored.
+ *
+ * @gdev:		The Guest extension device.
+ */
+static void vbg_guest_mappings_init(struct vbg_dev *gdev)
+{
+	struct vmmdev_hypervisorinfo *req;
+	void *guest_mappings[GUEST_MAPPINGS_TRIES];
+	struct page **pages = NULL;
+	u32 size, hypervisor_size;
+	int i, rc;
+
+	/* Query the required space. */
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_GET_HYPERVISOR_INFO,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return;
+
+	req->hypervisor_start = 0;
+	req->hypervisor_size = 0;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0)
+		goto out;
+
+	/*
+	 * The VMM will report back if there is nothing it wants to map, like
+	 * for instance in VT-x and AMD-V mode.
+	 */
+	if (req->hypervisor_size == 0)
+		goto out;
+
+	hypervisor_size = req->hypervisor_size;
+	/* Add 4M so that we can align the vmap to 4MiB as the host requires. */
+	size = PAGE_ALIGN(req->hypervisor_size) + SZ_4M;
+
+	pages = kmalloc_array(size >> PAGE_SHIFT, sizeof(*pages), GFP_KERNEL);
+	if (!pages)
+		goto out;
+
+	gdev->guest_mappings_dummy_page = alloc_page(GFP_HIGHUSER);
+	if (!gdev->guest_mappings_dummy_page)
+		goto out;
+
+	for (i = 0; i < (size >> PAGE_SHIFT); i++)
+		pages[i] = gdev->guest_mappings_dummy_page;
+
+	/*
+	 * Try several times, the VMM might not accept some addresses because
+	 * of address clashes between the three contexts.
+	 */
+	for (i = 0; i < GUEST_MAPPINGS_TRIES; i++) {
+		guest_mappings[i] = vmap(pages, (size >> PAGE_SHIFT),
+					 VM_MAP, PAGE_KERNEL_RO);
+		if (!guest_mappings[i])
+			break;
+
+		req->header.request_type = VMMDEVREQ_SET_HYPERVISOR_INFO;
+		req->header.rc = VERR_INTERNAL_ERROR;
+		req->hypervisor_size = hypervisor_size;
+		req->hypervisor_start =
+			(unsigned long)PTR_ALIGN(guest_mappings[i], SZ_4M);
+
+		rc = vbg_req_perform(gdev, req);
+		if (rc >= 0) {
+			gdev->guest_mappings = guest_mappings[i];
+			break;
+		}
+	}
+
+	/* Free vmap's from failed attempts. */
+	while (--i >= 0)
+		vunmap(guest_mappings[i]);
+
+	/* On failure free the dummy-page backing the vmap */
+	if (!gdev->guest_mappings) {
+		__free_page(gdev->guest_mappings_dummy_page);
+		gdev->guest_mappings_dummy_page = NULL;
+	}
+
+out:
+	vbg_req_free(req, sizeof(*req));
+	kfree(pages);
+}
+
+/**
+ * Undo what vbg_guest_mappings_init did.
+ *
+ * @gdev:		The Guest extension device.
+ */
+static void vbg_guest_mappings_exit(struct vbg_dev *gdev)
+{
+	struct vmmdev_hypervisorinfo *req;
+	int rc;
+
+	if (!gdev->guest_mappings)
+		return;
+
+	/*
+	 * Tell the host that we're going to free the memory we reserved for
+	 * it, the free it up. (Leak the memory if anything goes wrong here.)
+	 */
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_HYPERVISOR_INFO,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return;
+
+	req->hypervisor_start = 0;
+	req->hypervisor_size = 0;
+
+	rc = vbg_req_perform(gdev, req);
+
+	vbg_req_free(req, sizeof(*req));
+
+	if (rc < 0) {
+		vbg_err("%s error: %d\n", __func__, rc);
+		return;
+	}
+
+	vunmap(gdev->guest_mappings);
+	gdev->guest_mappings = NULL;
+
+	__free_page(gdev->guest_mappings_dummy_page);
+	gdev->guest_mappings_dummy_page = NULL;
+}
+
+/**
+ * Report the guest information to the host.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ */
+static int vbg_report_guest_info(struct vbg_dev *gdev)
+{
+	/*
+	 * Allocate and fill in the two guest info reports.
+	 */
+	struct vmmdev_guest_info *req1 = NULL;
+	struct vmmdev_guest_info2 *req2 = NULL;
+	int rc, ret = -ENOMEM;
+
+	req1 = vbg_req_alloc(sizeof(*req1), VMMDEVREQ_REPORT_GUEST_INFO,
+			     VBG_KERNEL_REQUEST);
+	req2 = vbg_req_alloc(sizeof(*req2), VMMDEVREQ_REPORT_GUEST_INFO2,
+			     VBG_KERNEL_REQUEST);
+	if (!req1 || !req2)
+		goto out_free;
+
+	req1->interface_version = VMMDEV_VERSION;
+	req1->os_type = VMMDEV_OSTYPE_LINUX26;
+#if __BITS_PER_LONG == 64
+	req1->os_type |= VMMDEV_OSTYPE_X64;
+#endif
+
+	req2->additions_major = VBG_VERSION_MAJOR;
+	req2->additions_minor = VBG_VERSION_MINOR;
+	req2->additions_build = VBG_VERSION_BUILD;
+	req2->additions_revision = VBG_SVN_REV;
+	req2->additions_features =
+		VMMDEV_GUEST_INFO2_ADDITIONS_FEATURES_REQUESTOR_INFO;
+	strlcpy(req2->name, VBG_VERSION_STRING,
+		sizeof(req2->name));
+
+	/*
+	 * There are two protocols here:
+	 *      1. INFO2 + INFO1. Supported by >=3.2.51.
+	 *      2. INFO1 and optionally INFO2. The old protocol.
+	 *
+	 * We try protocol 2 first.  It will fail with VERR_NOT_SUPPORTED
+	 * if not supported by the VMMDev (message ordering requirement).
+	 */
+	rc = vbg_req_perform(gdev, req2);
+	if (rc >= 0) {
+		rc = vbg_req_perform(gdev, req1);
+	} else if (rc == VERR_NOT_SUPPORTED || rc == VERR_NOT_IMPLEMENTED) {
+		rc = vbg_req_perform(gdev, req1);
+		if (rc >= 0) {
+			rc = vbg_req_perform(gdev, req2);
+			if (rc == VERR_NOT_IMPLEMENTED)
+				rc = VINF_SUCCESS;
+		}
+	}
+	ret = vbg_status_code_to_errno(rc);
+
+out_free:
+	vbg_req_free(req2, sizeof(*req2));
+	vbg_req_free(req1, sizeof(*req1));
+	return ret;
+}
+
+/**
+ * Report the guest driver status to the host.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @active:		Flag whether the driver is now active or not.
+ */
+static int vbg_report_driver_status(struct vbg_dev *gdev, bool active)
+{
+	struct vmmdev_guest_status *req;
+	int rc;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_REPORT_GUEST_STATUS,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	req->facility = VBOXGUEST_FACILITY_TYPE_VBOXGUEST_DRIVER;
+	if (active)
+		req->status = VBOXGUEST_FACILITY_STATUS_ACTIVE;
+	else
+		req->status = VBOXGUEST_FACILITY_STATUS_INACTIVE;
+	req->flags = 0;
+
+	rc = vbg_req_perform(gdev, req);
+	if (rc == VERR_NOT_IMPLEMENTED)	/* Compatibility with older hosts. */
+		rc = VINF_SUCCESS;
+
+	vbg_req_free(req, sizeof(*req));
+
+	return vbg_status_code_to_errno(rc);
+}
+
+/**
+ * Inflate the balloon by one chunk. The caller owns the balloon mutex.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @chunk_idx:		Index of the chunk.
+ */
+static int vbg_balloon_inflate(struct vbg_dev *gdev, u32 chunk_idx)
+{
+	struct vmmdev_memballoon_change *req = gdev->mem_balloon.change_req;
+	struct page **pages;
+	int i, rc, ret;
+
+	pages = kmalloc_array(VMMDEV_MEMORY_BALLOON_CHUNK_PAGES,
+			      sizeof(*pages),
+			      GFP_KERNEL | __GFP_NOWARN);
+	if (!pages)
+		return -ENOMEM;
+
+	req->header.size = sizeof(*req);
+	req->inflate = true;
+	req->pages = VMMDEV_MEMORY_BALLOON_CHUNK_PAGES;
+
+	for (i = 0; i < VMMDEV_MEMORY_BALLOON_CHUNK_PAGES; i++) {
+		pages[i] = alloc_page(GFP_KERNEL | __GFP_NOWARN);
+		if (!pages[i]) {
+			ret = -ENOMEM;
+			goto out_error;
+		}
+
+		req->phys_page[i] = page_to_phys(pages[i]);
+	}
+
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0) {
+		vbg_err("%s error, rc: %d\n", __func__, rc);
+		ret = vbg_status_code_to_errno(rc);
+		goto out_error;
+	}
+
+	gdev->mem_balloon.pages[chunk_idx] = pages;
+
+	return 0;
+
+out_error:
+	while (--i >= 0)
+		__free_page(pages[i]);
+	kfree(pages);
+
+	return ret;
+}
+
+/**
+ * Deflate the balloon by one chunk. The caller owns the balloon mutex.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @chunk_idx:		Index of the chunk.
+ */
+static int vbg_balloon_deflate(struct vbg_dev *gdev, u32 chunk_idx)
+{
+	struct vmmdev_memballoon_change *req = gdev->mem_balloon.change_req;
+	struct page **pages = gdev->mem_balloon.pages[chunk_idx];
+	int i, rc;
+
+	req->header.size = sizeof(*req);
+	req->inflate = false;
+	req->pages = VMMDEV_MEMORY_BALLOON_CHUNK_PAGES;
+
+	for (i = 0; i < VMMDEV_MEMORY_BALLOON_CHUNK_PAGES; i++)
+		req->phys_page[i] = page_to_phys(pages[i]);
+
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0) {
+		vbg_err("%s error, rc: %d\n", __func__, rc);
+		return vbg_status_code_to_errno(rc);
+	}
+
+	for (i = 0; i < VMMDEV_MEMORY_BALLOON_CHUNK_PAGES; i++)
+		__free_page(pages[i]);
+	kfree(pages);
+	gdev->mem_balloon.pages[chunk_idx] = NULL;
+
+	return 0;
+}
+
+/**
+ * Respond to VMMDEV_EVENT_BALLOON_CHANGE_REQUEST events, query the size
+ * the host wants the balloon to be and adjust accordingly.
+ */
+static void vbg_balloon_work(struct work_struct *work)
+{
+	struct vbg_dev *gdev =
+		container_of(work, struct vbg_dev, mem_balloon.work);
+	struct vmmdev_memballoon_info *req = gdev->mem_balloon.get_req;
+	u32 i, chunks;
+	int rc, ret;
+
+	/*
+	 * Setting this bit means that we request the value from the host and
+	 * change the guest memory balloon according to the returned value.
+	 */
+	req->event_ack = VMMDEV_EVENT_BALLOON_CHANGE_REQUEST;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0) {
+		vbg_err("%s error, rc: %d)\n", __func__, rc);
+		return;
+	}
+
+	/*
+	 * The host always returns the same maximum amount of chunks, so
+	 * we do this once.
+	 */
+	if (!gdev->mem_balloon.max_chunks) {
+		gdev->mem_balloon.pages =
+			devm_kcalloc(gdev->dev, req->phys_mem_chunks,
+				     sizeof(struct page **), GFP_KERNEL);
+		if (!gdev->mem_balloon.pages)
+			return;
+
+		gdev->mem_balloon.max_chunks = req->phys_mem_chunks;
+	}
+
+	chunks = req->balloon_chunks;
+	if (chunks > gdev->mem_balloon.max_chunks) {
+		vbg_err("%s: illegal balloon size %u (max=%u)\n",
+			__func__, chunks, gdev->mem_balloon.max_chunks);
+		return;
+	}
+
+	if (chunks > gdev->mem_balloon.chunks) {
+		/* inflate */
+		for (i = gdev->mem_balloon.chunks; i < chunks; i++) {
+			ret = vbg_balloon_inflate(gdev, i);
+			if (ret < 0)
+				return;
+
+			gdev->mem_balloon.chunks++;
+		}
+	} else {
+		/* deflate */
+		for (i = gdev->mem_balloon.chunks; i-- > chunks;) {
+			ret = vbg_balloon_deflate(gdev, i);
+			if (ret < 0)
+				return;
+
+			gdev->mem_balloon.chunks--;
+		}
+	}
+}
+
+/**
+ * Callback for heartbeat timer.
+ */
+static void vbg_heartbeat_timer(struct timer_list *t)
+{
+	struct vbg_dev *gdev = from_timer(gdev, t, heartbeat_timer);
+
+	vbg_req_perform(gdev, gdev->guest_heartbeat_req);
+	mod_timer(&gdev->heartbeat_timer,
+		  msecs_to_jiffies(gdev->heartbeat_interval_ms));
+}
+
+/**
+ * Configure the host to check guest's heartbeat
+ * and get heartbeat interval from the host.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @enabled:		Set true to enable guest heartbeat checks on host.
+ */
+static int vbg_heartbeat_host_config(struct vbg_dev *gdev, bool enabled)
+{
+	struct vmmdev_heartbeat *req;
+	int rc;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_HEARTBEAT_CONFIGURE,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	req->enabled = enabled;
+	req->interval_ns = 0;
+	rc = vbg_req_perform(gdev, req);
+	do_div(req->interval_ns, 1000000); /* ns -> ms */
+	gdev->heartbeat_interval_ms = req->interval_ns;
+	vbg_req_free(req, sizeof(*req));
+
+	return vbg_status_code_to_errno(rc);
+}
+
+/**
+ * Initializes the heartbeat timer. This feature may be disabled by the host.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ */
+static int vbg_heartbeat_init(struct vbg_dev *gdev)
+{
+	int ret;
+
+	/* Make sure that heartbeat checking is disabled if we fail. */
+	ret = vbg_heartbeat_host_config(gdev, false);
+	if (ret < 0)
+		return ret;
+
+	ret = vbg_heartbeat_host_config(gdev, true);
+	if (ret < 0)
+		return ret;
+
+	gdev->guest_heartbeat_req = vbg_req_alloc(
+					sizeof(*gdev->guest_heartbeat_req),
+					VMMDEVREQ_GUEST_HEARTBEAT,
+					VBG_KERNEL_REQUEST);
+	if (!gdev->guest_heartbeat_req)
+		return -ENOMEM;
+
+	vbg_info("%s: Setting up heartbeat to trigger every %d milliseconds\n",
+		 __func__, gdev->heartbeat_interval_ms);
+	mod_timer(&gdev->heartbeat_timer, 0);
+
+	return 0;
+}
+
+/**
+ * Cleanup hearbeat code, stop HB timer and disable host heartbeat checking.
+ * @gdev:		The Guest extension device.
+ */
+static void vbg_heartbeat_exit(struct vbg_dev *gdev)
+{
+	del_timer_sync(&gdev->heartbeat_timer);
+	vbg_heartbeat_host_config(gdev, false);
+	vbg_req_free(gdev->guest_heartbeat_req,
+		     sizeof(*gdev->guest_heartbeat_req));
+}
+
+/**
+ * Applies a change to the bit usage tracker.
+ * Return: true if the mask changed, false if not.
+ * @tracker:		The bit usage tracker.
+ * @changed:		The bits to change.
+ * @previous:		The previous value of the bits.
+ */
+static bool vbg_track_bit_usage(struct vbg_bit_usage_tracker *tracker,
+				u32 changed, u32 previous)
+{
+	bool global_change = false;
+
+	while (changed) {
+		u32 bit = ffs(changed) - 1;
+		u32 bitmask = BIT(bit);
+
+		if (bitmask & previous) {
+			tracker->per_bit_usage[bit] -= 1;
+			if (tracker->per_bit_usage[bit] == 0) {
+				global_change = true;
+				tracker->mask &= ~bitmask;
+			}
+		} else {
+			tracker->per_bit_usage[bit] += 1;
+			if (tracker->per_bit_usage[bit] == 1) {
+				global_change = true;
+				tracker->mask |= bitmask;
+			}
+		}
+
+		changed &= ~bitmask;
+	}
+
+	return global_change;
+}
+
+/**
+ * Init and termination worker for resetting the (host) event filter on the host
+ * Return: 0 or negative errno value.
+ * @gdev:		   The Guest extension device.
+ * @fixed_events:	   Fixed events (init time).
+ */
+static int vbg_reset_host_event_filter(struct vbg_dev *gdev,
+				       u32 fixed_events)
+{
+	struct vmmdev_mask *req;
+	int rc;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_CTL_GUEST_FILTER_MASK,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	req->not_mask = U32_MAX & ~fixed_events;
+	req->or_mask = fixed_events;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0)
+		vbg_err("%s error, rc: %d\n", __func__, rc);
+
+	vbg_req_free(req, sizeof(*req));
+	return vbg_status_code_to_errno(rc);
+}
+
+/**
+ * Changes the event filter mask for the given session.
+ *
+ * This is called in response to VBG_IOCTL_CHANGE_FILTER_MASK as well as to
+ * do session cleanup. Takes the session mutex.
+ *
+ * Return: 0 or negative errno value.
+ * @gdev:			The Guest extension device.
+ * @session:			The session.
+ * @or_mask:			The events to add.
+ * @not_mask:			The events to remove.
+ * @session_termination:	Set if we're called by the session cleanup code.
+ *				This tweaks the error handling so we perform
+ *				proper session cleanup even if the host
+ *				misbehaves.
+ */
+static int vbg_set_session_event_filter(struct vbg_dev *gdev,
+					struct vbg_session *session,
+					u32 or_mask, u32 not_mask,
+					bool session_termination)
+{
+	struct vmmdev_mask *req;
+	u32 changed, previous;
+	int rc, ret = 0;
+
+	/*
+	 * Allocate a request buffer before taking the spinlock, when
+	 * the session is being terminated the requestor is the kernel,
+	 * as we're cleaning up.
+	 */
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_CTL_GUEST_FILTER_MASK,
+			    session_termination ? VBG_KERNEL_REQUEST :
+						  session->requestor);
+	if (!req) {
+		if (!session_termination)
+			return -ENOMEM;
+		/* Ignore allocation failure, we must do session cleanup. */
+	}
+
+	mutex_lock(&gdev->session_mutex);
+
+	/* Apply the changes to the session mask. */
+	previous = session->event_filter;
+	session->event_filter |= or_mask;
+	session->event_filter &= ~not_mask;
+
+	/* If anything actually changed, update the global usage counters. */
+	changed = previous ^ session->event_filter;
+	if (!changed)
+		goto out;
+
+	vbg_track_bit_usage(&gdev->event_filter_tracker, changed, previous);
+	or_mask = gdev->fixed_events | gdev->event_filter_tracker.mask;
+
+	if (gdev->event_filter_host == or_mask || !req)
+		goto out;
+
+	gdev->event_filter_host = or_mask;
+	req->or_mask = or_mask;
+	req->not_mask = ~or_mask;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0) {
+		ret = vbg_status_code_to_errno(rc);
+
+		/* Failed, roll back (unless it's session termination time). */
+		gdev->event_filter_host = U32_MAX;
+		if (session_termination)
+			goto out;
+
+		vbg_track_bit_usage(&gdev->event_filter_tracker, changed,
+				    session->event_filter);
+		session->event_filter = previous;
+	}
+
+out:
+	mutex_unlock(&gdev->session_mutex);
+	vbg_req_free(req, sizeof(*req));
+
+	return ret;
+}
+
+/**
+ * Init and termination worker for set guest capabilities to zero on the host.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ */
+static int vbg_reset_host_capabilities(struct vbg_dev *gdev)
+{
+	struct vmmdev_mask *req;
+	int rc;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_GUEST_CAPABILITIES,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	req->not_mask = U32_MAX;
+	req->or_mask = 0;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0)
+		vbg_err("%s error, rc: %d\n", __func__, rc);
+
+	vbg_req_free(req, sizeof(*req));
+	return vbg_status_code_to_errno(rc);
+}
+
+/**
+ * Set guest capabilities on the host.
+ * Must be called with gdev->session_mutex hold.
+ * Return: 0 or negative errno value.
+ * @gdev:			The Guest extension device.
+ * @session:			The session.
+ * @session_termination:	Set if we're called by the session cleanup code.
+ */
+static int vbg_set_host_capabilities(struct vbg_dev *gdev,
+				     struct vbg_session *session,
+				     bool session_termination)
+{
+	struct vmmdev_mask *req;
+	u32 caps;
+	int rc;
+
+	WARN_ON(!mutex_is_locked(&gdev->session_mutex));
+
+	caps = gdev->acquired_guest_caps | gdev->set_guest_caps_tracker.mask;
+
+	if (gdev->guest_caps_host == caps)
+		return 0;
+
+	/* On termination the requestor is the kernel, as we're cleaning up. */
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_GUEST_CAPABILITIES,
+			    session_termination ? VBG_KERNEL_REQUEST :
+						  session->requestor);
+	if (!req) {
+		gdev->guest_caps_host = U32_MAX;
+		return -ENOMEM;
+	}
+
+	req->or_mask = caps;
+	req->not_mask = ~caps;
+	rc = vbg_req_perform(gdev, req);
+	vbg_req_free(req, sizeof(*req));
+
+	gdev->guest_caps_host = (rc >= 0) ? caps : U32_MAX;
+
+	return vbg_status_code_to_errno(rc);
+}
+
+/**
+ * Acquire (get exclusive access) guest capabilities for a session.
+ * Takes the session mutex.
+ * Return: 0 or negative errno value.
+ * @gdev:			The Guest extension device.
+ * @session:			The session.
+ * @flags:			Flags (VBGL_IOC_AGC_FLAGS_XXX).
+ * @or_mask:			The capabilities to add.
+ * @not_mask:			The capabilities to remove.
+ * @session_termination:	Set if we're called by the session cleanup code.
+ *				This tweaks the error handling so we perform
+ *				proper session cleanup even if the host
+ *				misbehaves.
+ */
+static int vbg_acquire_session_capabilities(struct vbg_dev *gdev,
+					    struct vbg_session *session,
+					    u32 or_mask, u32 not_mask,
+					    u32 flags, bool session_termination)
+{
+	unsigned long irqflags;
+	bool wakeup = false;
+	int ret = 0;
+
+	mutex_lock(&gdev->session_mutex);
+
+	if (gdev->set_guest_caps_tracker.mask & or_mask) {
+		vbg_err("%s error: cannot acquire caps which are currently set\n",
+			__func__);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/*
+	 * Mark any caps in the or_mask as now being in acquire-mode. Note
+	 * once caps are in acquire_mode they always stay in this mode.
+	 * This impacts event handling, so we take the event-lock.
+	 */
+	spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+	gdev->acquire_mode_guest_caps |= or_mask;
+	spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+	/* If we only have to switch the caps to acquire mode, we're done. */
+	if (flags & VBGL_IOC_AGC_FLAGS_CONFIG_ACQUIRE_MODE)
+		goto out;
+
+	not_mask &= ~or_mask; /* or_mask takes priority over not_mask */
+	not_mask &= session->acquired_guest_caps;
+	or_mask &= ~session->acquired_guest_caps;
+
+	if (or_mask == 0 && not_mask == 0)
+		goto out;
+
+	if (gdev->acquired_guest_caps & or_mask) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	gdev->acquired_guest_caps |= or_mask;
+	gdev->acquired_guest_caps &= ~not_mask;
+	/* session->acquired_guest_caps impacts event handling, take the lock */
+	spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+	session->acquired_guest_caps |= or_mask;
+	session->acquired_guest_caps &= ~not_mask;
+	spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+	ret = vbg_set_host_capabilities(gdev, session, session_termination);
+	/* Roll back on failure, unless it's session termination time. */
+	if (ret < 0 && !session_termination) {
+		gdev->acquired_guest_caps &= ~or_mask;
+		gdev->acquired_guest_caps |= not_mask;
+		spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+		session->acquired_guest_caps &= ~or_mask;
+		session->acquired_guest_caps |= not_mask;
+		spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+	}
+
+	/*
+	 * If we added a capability, check if that means some other thread in
+	 * our session should be unblocked because there are events pending
+	 * (the result of vbg_get_allowed_event_mask_for_session() may change).
+	 *
+	 * HACK ALERT! When the seamless support capability is added we generate
+	 *	a seamless change event so that the ring-3 client can sync with
+	 *	the seamless state.
+	 */
+	if (ret == 0 && or_mask != 0) {
+		spin_lock_irqsave(&gdev->event_spinlock, irqflags);
+
+		if (or_mask & VMMDEV_GUEST_SUPPORTS_SEAMLESS)
+			gdev->pending_events |=
+				VMMDEV_EVENT_SEAMLESS_MODE_CHANGE_REQUEST;
+
+		if (gdev->pending_events)
+			wakeup = true;
+
+		spin_unlock_irqrestore(&gdev->event_spinlock, irqflags);
+
+		if (wakeup)
+			wake_up(&gdev->event_wq);
+	}
+
+out:
+	mutex_unlock(&gdev->session_mutex);
+
+	return ret;
+}
+
+/**
+ * Sets the guest capabilities for a session. Takes the session mutex.
+ * Return: 0 or negative errno value.
+ * @gdev:			The Guest extension device.
+ * @session:			The session.
+ * @or_mask:			The capabilities to add.
+ * @not_mask:			The capabilities to remove.
+ * @session_termination:	Set if we're called by the session cleanup code.
+ *				This tweaks the error handling so we perform
+ *				proper session cleanup even if the host
+ *				misbehaves.
+ */
+static int vbg_set_session_capabilities(struct vbg_dev *gdev,
+					struct vbg_session *session,
+					u32 or_mask, u32 not_mask,
+					bool session_termination)
+{
+	u32 changed, previous;
+	int ret = 0;
+
+	mutex_lock(&gdev->session_mutex);
+
+	if (gdev->acquire_mode_guest_caps & or_mask) {
+		vbg_err("%s error: cannot set caps which are in acquire_mode\n",
+			__func__);
+		ret = -EBUSY;
+		goto out;
+	}
+
+	/* Apply the changes to the session mask. */
+	previous = session->set_guest_caps;
+	session->set_guest_caps |= or_mask;
+	session->set_guest_caps &= ~not_mask;
+
+	/* If anything actually changed, update the global usage counters. */
+	changed = previous ^ session->set_guest_caps;
+	if (!changed)
+		goto out;
+
+	vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed, previous);
+
+	ret = vbg_set_host_capabilities(gdev, session, session_termination);
+	/* Roll back on failure, unless it's session termination time. */
+	if (ret < 0 && !session_termination) {
+		vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed,
+				    session->set_guest_caps);
+		session->set_guest_caps = previous;
+	}
+
+out:
+	mutex_unlock(&gdev->session_mutex);
+
+	return ret;
+}
+
+/**
+ * vbg_query_host_version get the host feature mask and version information.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ */
+static int vbg_query_host_version(struct vbg_dev *gdev)
+{
+	struct vmmdev_host_version *req;
+	int rc, ret;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_GET_HOST_VERSION,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	rc = vbg_req_perform(gdev, req);
+	ret = vbg_status_code_to_errno(rc);
+	if (ret) {
+		vbg_err("%s error: %d\n", __func__, rc);
+		goto out;
+	}
+
+	snprintf(gdev->host_version, sizeof(gdev->host_version), "%u.%u.%ur%u",
+		 req->major, req->minor, req->build, req->revision);
+	gdev->host_features = req->features;
+
+	vbg_info("vboxguest: host-version: %s %#x\n", gdev->host_version,
+		 gdev->host_features);
+
+	if (!(req->features & VMMDEV_HVF_HGCM_PHYS_PAGE_LIST)) {
+		vbg_err("vboxguest: Error host too old (does not support page-lists)\n");
+		ret = -ENODEV;
+	}
+
+out:
+	vbg_req_free(req, sizeof(*req));
+	return ret;
+}
+
+/**
+ * Initializes the VBoxGuest device extension when the
+ * device driver is loaded.
+ *
+ * The native code locates the VMMDev on the PCI bus and retrieve
+ * the MMIO and I/O port ranges, this function will take care of
+ * mapping the MMIO memory (if present). Upon successful return
+ * the native code should set up the interrupt handler.
+ *
+ * Return: 0 or negative errno value.
+ *
+ * @gdev:		The Guest extension device.
+ * @fixed_events:	Events that will be enabled upon init and no client
+ *			will ever be allowed to mask.
+ */
+int vbg_core_init(struct vbg_dev *gdev, u32 fixed_events)
+{
+	int ret = -ENOMEM;
+
+	gdev->fixed_events = fixed_events | VMMDEV_EVENT_HGCM;
+	gdev->event_filter_host = U32_MAX;	/* forces a report */
+	gdev->guest_caps_host = U32_MAX;	/* forces a report */
+
+	init_waitqueue_head(&gdev->event_wq);
+	init_waitqueue_head(&gdev->hgcm_wq);
+	spin_lock_init(&gdev->event_spinlock);
+	mutex_init(&gdev->session_mutex);
+	mutex_init(&gdev->cancel_req_mutex);
+	timer_setup(&gdev->heartbeat_timer, vbg_heartbeat_timer, 0);
+	INIT_WORK(&gdev->mem_balloon.work, vbg_balloon_work);
+
+	gdev->mem_balloon.get_req =
+		vbg_req_alloc(sizeof(*gdev->mem_balloon.get_req),
+			      VMMDEVREQ_GET_MEMBALLOON_CHANGE_REQ,
+			      VBG_KERNEL_REQUEST);
+	gdev->mem_balloon.change_req =
+		vbg_req_alloc(sizeof(*gdev->mem_balloon.change_req),
+			      VMMDEVREQ_CHANGE_MEMBALLOON,
+			      VBG_KERNEL_REQUEST);
+	gdev->cancel_req =
+		vbg_req_alloc(sizeof(*(gdev->cancel_req)),
+			      VMMDEVREQ_HGCM_CANCEL2,
+			      VBG_KERNEL_REQUEST);
+	gdev->ack_events_req =
+		vbg_req_alloc(sizeof(*gdev->ack_events_req),
+			      VMMDEVREQ_ACKNOWLEDGE_EVENTS,
+			      VBG_KERNEL_REQUEST);
+	gdev->mouse_status_req =
+		vbg_req_alloc(sizeof(*gdev->mouse_status_req),
+			      VMMDEVREQ_GET_MOUSE_STATUS,
+			      VBG_KERNEL_REQUEST);
+
+	if (!gdev->mem_balloon.get_req || !gdev->mem_balloon.change_req ||
+	    !gdev->cancel_req || !gdev->ack_events_req ||
+	    !gdev->mouse_status_req)
+		goto err_free_reqs;
+
+	ret = vbg_query_host_version(gdev);
+	if (ret)
+		goto err_free_reqs;
+
+	ret = vbg_report_guest_info(gdev);
+	if (ret) {
+		vbg_err("vboxguest: vbg_report_guest_info error: %d\n", ret);
+		goto err_free_reqs;
+	}
+
+	ret = vbg_reset_host_event_filter(gdev, gdev->fixed_events);
+	if (ret) {
+		vbg_err("vboxguest: Error setting fixed event filter: %d\n",
+			ret);
+		goto err_free_reqs;
+	}
+
+	ret = vbg_reset_host_capabilities(gdev);
+	if (ret) {
+		vbg_err("vboxguest: Error clearing guest capabilities: %d\n",
+			ret);
+		goto err_free_reqs;
+	}
+
+	ret = vbg_core_set_mouse_status(gdev, 0);
+	if (ret) {
+		vbg_err("vboxguest: Error clearing mouse status: %d\n", ret);
+		goto err_free_reqs;
+	}
+
+	/* These may fail without requiring the driver init to fail. */
+	vbg_guest_mappings_init(gdev);
+	vbg_heartbeat_init(gdev);
+
+	/* All Done! */
+	ret = vbg_report_driver_status(gdev, true);
+	if (ret < 0)
+		vbg_err("vboxguest: Error reporting driver status: %d\n", ret);
+
+	return 0;
+
+err_free_reqs:
+	vbg_req_free(gdev->mouse_status_req,
+		     sizeof(*gdev->mouse_status_req));
+	vbg_req_free(gdev->ack_events_req,
+		     sizeof(*gdev->ack_events_req));
+	vbg_req_free(gdev->cancel_req,
+		     sizeof(*gdev->cancel_req));
+	vbg_req_free(gdev->mem_balloon.change_req,
+		     sizeof(*gdev->mem_balloon.change_req));
+	vbg_req_free(gdev->mem_balloon.get_req,
+		     sizeof(*gdev->mem_balloon.get_req));
+	return ret;
+}
+
+/**
+ * Call this on exit to clean-up vboxguest-core managed resources.
+ *
+ * The native code should call this before the driver is loaded,
+ * but don't call this on shutdown.
+ * @gdev:		The Guest extension device.
+ */
+void vbg_core_exit(struct vbg_dev *gdev)
+{
+	vbg_heartbeat_exit(gdev);
+	vbg_guest_mappings_exit(gdev);
+
+	/* Clear the host flags (mouse status etc). */
+	vbg_reset_host_event_filter(gdev, 0);
+	vbg_reset_host_capabilities(gdev);
+	vbg_core_set_mouse_status(gdev, 0);
+
+	vbg_req_free(gdev->mouse_status_req,
+		     sizeof(*gdev->mouse_status_req));
+	vbg_req_free(gdev->ack_events_req,
+		     sizeof(*gdev->ack_events_req));
+	vbg_req_free(gdev->cancel_req,
+		     sizeof(*gdev->cancel_req));
+	vbg_req_free(gdev->mem_balloon.change_req,
+		     sizeof(*gdev->mem_balloon.change_req));
+	vbg_req_free(gdev->mem_balloon.get_req,
+		     sizeof(*gdev->mem_balloon.get_req));
+}
+
+/**
+ * Creates a VBoxGuest user session.
+ *
+ * vboxguest_linux.c calls this when userspace opens the char-device.
+ * Return: A pointer to the new session or an ERR_PTR on error.
+ * @gdev:		The Guest extension device.
+ * @requestor:		VMMDEV_REQUESTOR_* flags
+ */
+struct vbg_session *vbg_core_open_session(struct vbg_dev *gdev, u32 requestor)
+{
+	struct vbg_session *session;
+
+	session = kzalloc(sizeof(*session), GFP_KERNEL);
+	if (!session)
+		return ERR_PTR(-ENOMEM);
+
+	session->gdev = gdev;
+	session->requestor = requestor;
+
+	return session;
+}
+
+/**
+ * Closes a VBoxGuest session.
+ * @session:		The session to close (and free).
+ */
+void vbg_core_close_session(struct vbg_session *session)
+{
+	struct vbg_dev *gdev = session->gdev;
+	int i, rc;
+
+	vbg_acquire_session_capabilities(gdev, session, 0, U32_MAX, 0, true);
+	vbg_set_session_capabilities(gdev, session, 0, U32_MAX, true);
+	vbg_set_session_event_filter(gdev, session, 0, U32_MAX, true);
+
+	for (i = 0; i < ARRAY_SIZE(session->hgcm_client_ids); i++) {
+		if (!session->hgcm_client_ids[i])
+			continue;
+
+		/* requestor is kernel here, as we're cleaning up. */
+		vbg_hgcm_disconnect(gdev, VBG_KERNEL_REQUEST,
+				    session->hgcm_client_ids[i], &rc);
+	}
+
+	kfree(session);
+}
+
+static int vbg_ioctl_chk(struct vbg_ioctl_hdr *hdr, size_t in_size,
+			 size_t out_size)
+{
+	if (hdr->size_in  != (sizeof(*hdr) + in_size) ||
+	    hdr->size_out != (sizeof(*hdr) + out_size))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int vbg_ioctl_driver_version_info(
+	struct vbg_ioctl_driver_version_info *info)
+{
+	const u16 vbg_maj_version = VBG_IOC_VERSION >> 16;
+	u16 min_maj_version, req_maj_version;
+
+	if (vbg_ioctl_chk(&info->hdr, sizeof(info->u.in), sizeof(info->u.out)))
+		return -EINVAL;
+
+	req_maj_version = info->u.in.req_version >> 16;
+	min_maj_version = info->u.in.min_version >> 16;
+
+	if (info->u.in.min_version > info->u.in.req_version ||
+	    min_maj_version != req_maj_version)
+		return -EINVAL;
+
+	if (info->u.in.min_version <= VBG_IOC_VERSION &&
+	    min_maj_version == vbg_maj_version) {
+		info->u.out.session_version = VBG_IOC_VERSION;
+	} else {
+		info->u.out.session_version = U32_MAX;
+		info->hdr.rc = VERR_VERSION_MISMATCH;
+	}
+
+	info->u.out.driver_version  = VBG_IOC_VERSION;
+	info->u.out.driver_revision = 0;
+	info->u.out.reserved1      = 0;
+	info->u.out.reserved2      = 0;
+
+	return 0;
+}
+
+/* Must be called with the event_lock held */
+static u32 vbg_get_allowed_event_mask_for_session(struct vbg_dev *gdev,
+						  struct vbg_session *session)
+{
+	u32 acquire_mode_caps = gdev->acquire_mode_guest_caps;
+	u32 session_acquired_caps = session->acquired_guest_caps;
+	u32 allowed_events = VMMDEV_EVENT_VALID_EVENT_MASK;
+
+	if ((acquire_mode_caps & VMMDEV_GUEST_SUPPORTS_GRAPHICS) &&
+	    !(session_acquired_caps & VMMDEV_GUEST_SUPPORTS_GRAPHICS))
+		allowed_events &= ~VMMDEV_EVENT_DISPLAY_CHANGE_REQUEST;
+
+	if ((acquire_mode_caps & VMMDEV_GUEST_SUPPORTS_SEAMLESS) &&
+	    !(session_acquired_caps & VMMDEV_GUEST_SUPPORTS_SEAMLESS))
+		allowed_events &= ~VMMDEV_EVENT_SEAMLESS_MODE_CHANGE_REQUEST;
+
+	return allowed_events;
+}
+
+static bool vbg_wait_event_cond(struct vbg_dev *gdev,
+				struct vbg_session *session,
+				u32 event_mask)
+{
+	unsigned long flags;
+	bool wakeup;
+	u32 events;
+
+	spin_lock_irqsave(&gdev->event_spinlock, flags);
+
+	events = gdev->pending_events & event_mask;
+	events &= vbg_get_allowed_event_mask_for_session(gdev, session);
+	wakeup = events || session->cancel_waiters;
+
+	spin_unlock_irqrestore(&gdev->event_spinlock, flags);
+
+	return wakeup;
+}
+
+/* Must be called with the event_lock held */
+static u32 vbg_consume_events_locked(struct vbg_dev *gdev,
+				     struct vbg_session *session,
+				     u32 event_mask)
+{
+	u32 events = gdev->pending_events & event_mask;
+
+	events &= vbg_get_allowed_event_mask_for_session(gdev, session);
+	gdev->pending_events &= ~events;
+	return events;
+}
+
+static int vbg_ioctl_wait_for_events(struct vbg_dev *gdev,
+				     struct vbg_session *session,
+				     struct vbg_ioctl_wait_for_events *wait)
+{
+	u32 timeout_ms = wait->u.in.timeout_ms;
+	u32 event_mask = wait->u.in.events;
+	unsigned long flags;
+	long timeout;
+	int ret = 0;
+
+	if (vbg_ioctl_chk(&wait->hdr, sizeof(wait->u.in), sizeof(wait->u.out)))
+		return -EINVAL;
+
+	if (timeout_ms == U32_MAX)
+		timeout = MAX_SCHEDULE_TIMEOUT;
+	else
+		timeout = msecs_to_jiffies(timeout_ms);
+
+	wait->u.out.events = 0;
+	do {
+		timeout = wait_event_interruptible_timeout(
+				gdev->event_wq,
+				vbg_wait_event_cond(gdev, session, event_mask),
+				timeout);
+
+		spin_lock_irqsave(&gdev->event_spinlock, flags);
+
+		if (timeout < 0 || session->cancel_waiters) {
+			ret = -EINTR;
+		} else if (timeout == 0) {
+			ret = -ETIMEDOUT;
+		} else {
+			wait->u.out.events =
+			   vbg_consume_events_locked(gdev, session, event_mask);
+		}
+
+		spin_unlock_irqrestore(&gdev->event_spinlock, flags);
+
+		/*
+		 * Someone else may have consumed the event(s) first, in
+		 * which case we go back to waiting.
+		 */
+	} while (ret == 0 && wait->u.out.events == 0);
+
+	return ret;
+}
+
+static int vbg_ioctl_interrupt_all_wait_events(struct vbg_dev *gdev,
+					       struct vbg_session *session,
+					       struct vbg_ioctl_hdr *hdr)
+{
+	unsigned long flags;
+
+	if (hdr->size_in != sizeof(*hdr) || hdr->size_out != sizeof(*hdr))
+		return -EINVAL;
+
+	spin_lock_irqsave(&gdev->event_spinlock, flags);
+	session->cancel_waiters = true;
+	spin_unlock_irqrestore(&gdev->event_spinlock, flags);
+
+	wake_up(&gdev->event_wq);
+
+	return 0;
+}
+
+/**
+ * Checks if the VMM request is allowed in the context of the given session.
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @session:		The calling session.
+ * @req:		The request.
+ */
+static int vbg_req_allowed(struct vbg_dev *gdev, struct vbg_session *session,
+			   const struct vmmdev_request_header *req)
+{
+	const struct vmmdev_guest_status *guest_status;
+	bool trusted_apps_only;
+
+	switch (req->request_type) {
+	/* Trusted users apps only. */
+	case VMMDEVREQ_QUERY_CREDENTIALS:
+	case VMMDEVREQ_REPORT_CREDENTIALS_JUDGEMENT:
+	case VMMDEVREQ_REGISTER_SHARED_MODULE:
+	case VMMDEVREQ_UNREGISTER_SHARED_MODULE:
+	case VMMDEVREQ_WRITE_COREDUMP:
+	case VMMDEVREQ_GET_CPU_HOTPLUG_REQ:
+	case VMMDEVREQ_SET_CPU_HOTPLUG_STATUS:
+	case VMMDEVREQ_CHECK_SHARED_MODULES:
+	case VMMDEVREQ_GET_PAGE_SHARING_STATUS:
+	case VMMDEVREQ_DEBUG_IS_PAGE_SHARED:
+	case VMMDEVREQ_REPORT_GUEST_STATS:
+	case VMMDEVREQ_REPORT_GUEST_USER_STATE:
+	case VMMDEVREQ_GET_STATISTICS_CHANGE_REQ:
+		trusted_apps_only = true;
+		break;
+
+	/* Anyone. */
+	case VMMDEVREQ_GET_MOUSE_STATUS:
+	case VMMDEVREQ_SET_MOUSE_STATUS:
+	case VMMDEVREQ_SET_POINTER_SHAPE:
+	case VMMDEVREQ_GET_HOST_VERSION:
+	case VMMDEVREQ_IDLE:
+	case VMMDEVREQ_GET_HOST_TIME:
+	case VMMDEVREQ_SET_POWER_STATUS:
+	case VMMDEVREQ_ACKNOWLEDGE_EVENTS:
+	case VMMDEVREQ_CTL_GUEST_FILTER_MASK:
+	case VMMDEVREQ_REPORT_GUEST_STATUS:
+	case VMMDEVREQ_GET_DISPLAY_CHANGE_REQ:
+	case VMMDEVREQ_VIDEMODE_SUPPORTED:
+	case VMMDEVREQ_GET_HEIGHT_REDUCTION:
+	case VMMDEVREQ_GET_DISPLAY_CHANGE_REQ2:
+	case VMMDEVREQ_VIDEMODE_SUPPORTED2:
+	case VMMDEVREQ_VIDEO_ACCEL_ENABLE:
+	case VMMDEVREQ_VIDEO_ACCEL_FLUSH:
+	case VMMDEVREQ_VIDEO_SET_VISIBLE_REGION:
+	case VMMDEVREQ_VIDEO_UPDATE_MONITOR_POSITIONS:
+	case VMMDEVREQ_GET_DISPLAY_CHANGE_REQEX:
+	case VMMDEVREQ_GET_DISPLAY_CHANGE_REQ_MULTI:
+	case VMMDEVREQ_GET_SEAMLESS_CHANGE_REQ:
+	case VMMDEVREQ_GET_VRDPCHANGE_REQ:
+	case VMMDEVREQ_LOG_STRING:
+	case VMMDEVREQ_GET_SESSION_ID:
+		trusted_apps_only = false;
+		break;
+
+	/* Depends on the request parameters... */
+	case VMMDEVREQ_REPORT_GUEST_CAPABILITIES:
+		guest_status = (const struct vmmdev_guest_status *)req;
+		switch (guest_status->facility) {
+		case VBOXGUEST_FACILITY_TYPE_ALL:
+		case VBOXGUEST_FACILITY_TYPE_VBOXGUEST_DRIVER:
+			vbg_err("Denying userspace vmm report guest cap. call facility %#08x\n",
+				guest_status->facility);
+			return -EPERM;
+		case VBOXGUEST_FACILITY_TYPE_VBOX_SERVICE:
+			trusted_apps_only = true;
+			break;
+		case VBOXGUEST_FACILITY_TYPE_VBOX_TRAY_CLIENT:
+		case VBOXGUEST_FACILITY_TYPE_SEAMLESS:
+		case VBOXGUEST_FACILITY_TYPE_GRAPHICS:
+		default:
+			trusted_apps_only = false;
+			break;
+		}
+		break;
+
+	/* Anything else is not allowed. */
+	default:
+		vbg_err("Denying userspace vmm call type %#08x\n",
+			req->request_type);
+		return -EPERM;
+	}
+
+	if (trusted_apps_only &&
+	    (session->requestor & VMMDEV_REQUESTOR_USER_DEVICE)) {
+		vbg_err("Denying userspace vmm call type %#08x through vboxuser device node\n",
+			req->request_type);
+		return -EPERM;
+	}
+
+	return 0;
+}
+
+static int vbg_ioctl_vmmrequest(struct vbg_dev *gdev,
+				struct vbg_session *session, void *data)
+{
+	struct vbg_ioctl_hdr *hdr = data;
+	int ret;
+
+	if (hdr->size_in != hdr->size_out)
+		return -EINVAL;
+
+	if (hdr->size_in > VMMDEV_MAX_VMMDEVREQ_SIZE)
+		return -E2BIG;
+
+	if (hdr->type == VBG_IOCTL_HDR_TYPE_DEFAULT)
+		return -EINVAL;
+
+	ret = vbg_req_allowed(gdev, session, data);
+	if (ret < 0)
+		return ret;
+
+	vbg_req_perform(gdev, data);
+	WARN_ON(hdr->rc == VINF_HGCM_ASYNC_EXECUTE);
+
+	return 0;
+}
+
+static int vbg_ioctl_hgcm_connect(struct vbg_dev *gdev,
+				  struct vbg_session *session,
+				  struct vbg_ioctl_hgcm_connect *conn)
+{
+	u32 client_id;
+	int i, ret;
+
+	if (vbg_ioctl_chk(&conn->hdr, sizeof(conn->u.in), sizeof(conn->u.out)))
+		return -EINVAL;
+
+	/* Find a free place in the sessions clients array and claim it */
+	mutex_lock(&gdev->session_mutex);
+	for (i = 0; i < ARRAY_SIZE(session->hgcm_client_ids); i++) {
+		if (!session->hgcm_client_ids[i]) {
+			session->hgcm_client_ids[i] = U32_MAX;
+			break;
+		}
+	}
+	mutex_unlock(&gdev->session_mutex);
+
+	if (i >= ARRAY_SIZE(session->hgcm_client_ids))
+		return -EMFILE;
+
+	ret = vbg_hgcm_connect(gdev, session->requestor, &conn->u.in.loc,
+			       &client_id, &conn->hdr.rc);
+
+	mutex_lock(&gdev->session_mutex);
+	if (ret == 0 && conn->hdr.rc >= 0) {
+		conn->u.out.client_id = client_id;
+		session->hgcm_client_ids[i] = client_id;
+	} else {
+		conn->u.out.client_id = 0;
+		session->hgcm_client_ids[i] = 0;
+	}
+	mutex_unlock(&gdev->session_mutex);
+
+	return ret;
+}
+
+static int vbg_ioctl_hgcm_disconnect(struct vbg_dev *gdev,
+				     struct vbg_session *session,
+				     struct vbg_ioctl_hgcm_disconnect *disconn)
+{
+	u32 client_id;
+	int i, ret;
+
+	if (vbg_ioctl_chk(&disconn->hdr, sizeof(disconn->u.in), 0))
+		return -EINVAL;
+
+	client_id = disconn->u.in.client_id;
+	if (client_id == 0 || client_id == U32_MAX)
+		return -EINVAL;
+
+	mutex_lock(&gdev->session_mutex);
+	for (i = 0; i < ARRAY_SIZE(session->hgcm_client_ids); i++) {
+		if (session->hgcm_client_ids[i] == client_id) {
+			session->hgcm_client_ids[i] = U32_MAX;
+			break;
+		}
+	}
+	mutex_unlock(&gdev->session_mutex);
+
+	if (i >= ARRAY_SIZE(session->hgcm_client_ids))
+		return -EINVAL;
+
+	ret = vbg_hgcm_disconnect(gdev, session->requestor, client_id,
+				  &disconn->hdr.rc);
+
+	mutex_lock(&gdev->session_mutex);
+	if (ret == 0 && disconn->hdr.rc >= 0)
+		session->hgcm_client_ids[i] = 0;
+	else
+		session->hgcm_client_ids[i] = client_id;
+	mutex_unlock(&gdev->session_mutex);
+
+	return ret;
+}
+
+static bool vbg_param_valid(enum vmmdev_hgcm_function_parameter_type type)
+{
+	switch (type) {
+	case VMMDEV_HGCM_PARM_TYPE_32BIT:
+	case VMMDEV_HGCM_PARM_TYPE_64BIT:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static int vbg_ioctl_hgcm_call(struct vbg_dev *gdev,
+			       struct vbg_session *session, bool f32bit,
+			       struct vbg_ioctl_hgcm_call *call)
+{
+	size_t actual_size;
+	u32 client_id;
+	int i, ret;
+
+	if (call->hdr.size_in < sizeof(*call))
+		return -EINVAL;
+
+	if (call->hdr.size_in != call->hdr.size_out)
+		return -EINVAL;
+
+	if (call->parm_count > VMMDEV_HGCM_MAX_PARMS)
+		return -E2BIG;
+
+	client_id = call->client_id;
+	if (client_id == 0 || client_id == U32_MAX)
+		return -EINVAL;
+
+	actual_size = sizeof(*call);
+	if (f32bit)
+		actual_size += call->parm_count *
+			       sizeof(struct vmmdev_hgcm_function_parameter32);
+	else
+		actual_size += call->parm_count *
+			       sizeof(struct vmmdev_hgcm_function_parameter);
+	if (call->hdr.size_in < actual_size) {
+		vbg_debug("VBG_IOCTL_HGCM_CALL: hdr.size_in %d required size is %zd\n",
+			  call->hdr.size_in, actual_size);
+		return -EINVAL;
+	}
+	call->hdr.size_out = actual_size;
+
+	/* Validate parameter types */
+	if (f32bit) {
+		struct vmmdev_hgcm_function_parameter32 *parm =
+			VBG_IOCTL_HGCM_CALL_PARMS32(call);
+
+		for (i = 0; i < call->parm_count; i++)
+			if (!vbg_param_valid(parm[i].type))
+				return -EINVAL;
+	} else {
+		struct vmmdev_hgcm_function_parameter *parm =
+			VBG_IOCTL_HGCM_CALL_PARMS(call);
+
+		for (i = 0; i < call->parm_count; i++)
+			if (!vbg_param_valid(parm[i].type))
+				return -EINVAL;
+	}
+
+	/*
+	 * Validate the client id.
+	 */
+	mutex_lock(&gdev->session_mutex);
+	for (i = 0; i < ARRAY_SIZE(session->hgcm_client_ids); i++)
+		if (session->hgcm_client_ids[i] == client_id)
+			break;
+	mutex_unlock(&gdev->session_mutex);
+	if (i >= ARRAY_SIZE(session->hgcm_client_ids)) {
+		vbg_debug("VBG_IOCTL_HGCM_CALL: INVALID handle. u32Client=%#08x\n",
+			  client_id);
+		return -EINVAL;
+	}
+
+	if (IS_ENABLED(CONFIG_COMPAT) && f32bit)
+		ret = vbg_hgcm_call32(gdev, session->requestor, client_id,
+				      call->function, call->timeout_ms,
+				      VBG_IOCTL_HGCM_CALL_PARMS32(call),
+				      call->parm_count, &call->hdr.rc);
+	else
+		ret = vbg_hgcm_call(gdev, session->requestor, client_id,
+				    call->function, call->timeout_ms,
+				    VBG_IOCTL_HGCM_CALL_PARMS(call),
+				    call->parm_count, &call->hdr.rc);
+
+	if (ret == -E2BIG) {
+		/* E2BIG needs to be reported through the hdr.rc field. */
+		call->hdr.rc = VERR_OUT_OF_RANGE;
+		ret = 0;
+	}
+
+	if (ret && ret != -EINTR && ret != -ETIMEDOUT)
+		vbg_err("VBG_IOCTL_HGCM_CALL error: %d\n", ret);
+
+	return ret;
+}
+
+static int vbg_ioctl_log(struct vbg_ioctl_log *log)
+{
+	if (log->hdr.size_out != sizeof(log->hdr))
+		return -EINVAL;
+
+	vbg_info("%.*s", (int)(log->hdr.size_in - sizeof(log->hdr)),
+		 log->u.in.msg);
+
+	return 0;
+}
+
+static int vbg_ioctl_change_filter_mask(struct vbg_dev *gdev,
+					struct vbg_session *session,
+					struct vbg_ioctl_change_filter *filter)
+{
+	u32 or_mask, not_mask;
+
+	if (vbg_ioctl_chk(&filter->hdr, sizeof(filter->u.in), 0))
+		return -EINVAL;
+
+	or_mask = filter->u.in.or_mask;
+	not_mask = filter->u.in.not_mask;
+
+	if ((or_mask | not_mask) & ~VMMDEV_EVENT_VALID_EVENT_MASK)
+		return -EINVAL;
+
+	return vbg_set_session_event_filter(gdev, session, or_mask, not_mask,
+					    false);
+}
+
+static int vbg_ioctl_acquire_guest_capabilities(struct vbg_dev *gdev,
+	     struct vbg_session *session,
+	     struct vbg_ioctl_acquire_guest_caps *caps)
+{
+	u32 flags, or_mask, not_mask;
+
+	if (vbg_ioctl_chk(&caps->hdr, sizeof(caps->u.in), 0))
+		return -EINVAL;
+
+	flags = caps->u.in.flags;
+	or_mask = caps->u.in.or_mask;
+	not_mask = caps->u.in.not_mask;
+
+	if (flags & ~VBGL_IOC_AGC_FLAGS_VALID_MASK)
+		return -EINVAL;
+
+	if ((or_mask | not_mask) & ~VMMDEV_GUEST_CAPABILITIES_MASK)
+		return -EINVAL;
+
+	return vbg_acquire_session_capabilities(gdev, session, or_mask,
+						not_mask, flags, false);
+}
+
+static int vbg_ioctl_change_guest_capabilities(struct vbg_dev *gdev,
+	     struct vbg_session *session, struct vbg_ioctl_set_guest_caps *caps)
+{
+	u32 or_mask, not_mask;
+	int ret;
+
+	if (vbg_ioctl_chk(&caps->hdr, sizeof(caps->u.in), sizeof(caps->u.out)))
+		return -EINVAL;
+
+	or_mask = caps->u.in.or_mask;
+	not_mask = caps->u.in.not_mask;
+
+	if ((or_mask | not_mask) & ~VMMDEV_GUEST_CAPABILITIES_MASK)
+		return -EINVAL;
+
+	ret = vbg_set_session_capabilities(gdev, session, or_mask, not_mask,
+					   false);
+	if (ret)
+		return ret;
+
+	caps->u.out.session_caps = session->set_guest_caps;
+	caps->u.out.global_caps = gdev->guest_caps_host;
+
+	return 0;
+}
+
+static int vbg_ioctl_check_balloon(struct vbg_dev *gdev,
+				   struct vbg_ioctl_check_balloon *balloon_info)
+{
+	if (vbg_ioctl_chk(&balloon_info->hdr, 0, sizeof(balloon_info->u.out)))
+		return -EINVAL;
+
+	balloon_info->u.out.balloon_chunks = gdev->mem_balloon.chunks;
+	/*
+	 * Under Linux we handle VMMDEV_EVENT_BALLOON_CHANGE_REQUEST
+	 * events entirely in the kernel, see vbg_core_isr().
+	 */
+	balloon_info->u.out.handle_in_r3 = false;
+
+	return 0;
+}
+
+static int vbg_ioctl_write_core_dump(struct vbg_dev *gdev,
+				     struct vbg_session *session,
+				     struct vbg_ioctl_write_coredump *dump)
+{
+	struct vmmdev_write_core_dump *req;
+
+	if (vbg_ioctl_chk(&dump->hdr, sizeof(dump->u.in), 0))
+		return -EINVAL;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_WRITE_COREDUMP,
+			    session->requestor);
+	if (!req)
+		return -ENOMEM;
+
+	req->flags = dump->u.in.flags;
+	dump->hdr.rc = vbg_req_perform(gdev, req);
+
+	vbg_req_free(req, sizeof(*req));
+	return 0;
+}
+
+/**
+ * Common IOCtl for user to kernel communication.
+ * Return: 0 or negative errno value.
+ * @session:	The client session.
+ * @req:	The requested function.
+ * @data:	The i/o data buffer, minimum size sizeof(struct vbg_ioctl_hdr).
+ */
+int vbg_core_ioctl(struct vbg_session *session, unsigned int req, void *data)
+{
+	unsigned int req_no_size = req & ~IOCSIZE_MASK;
+	struct vbg_dev *gdev = session->gdev;
+	struct vbg_ioctl_hdr *hdr = data;
+	bool f32bit = false;
+
+	hdr->rc = VINF_SUCCESS;
+	if (!hdr->size_out)
+		hdr->size_out = hdr->size_in;
+
+	/*
+	 * hdr->version and hdr->size_in / hdr->size_out minimum size are
+	 * already checked by vbg_misc_device_ioctl().
+	 */
+
+	/* For VMMDEV_REQUEST hdr->type != VBG_IOCTL_HDR_TYPE_DEFAULT */
+	if (req_no_size == VBG_IOCTL_VMMDEV_REQUEST(0) ||
+	    req == VBG_IOCTL_VMMDEV_REQUEST_BIG ||
+	    req == VBG_IOCTL_VMMDEV_REQUEST_BIG_ALT)
+		return vbg_ioctl_vmmrequest(gdev, session, data);
+
+	if (hdr->type != VBG_IOCTL_HDR_TYPE_DEFAULT)
+		return -EINVAL;
+
+	/* Fixed size requests. */
+	switch (req) {
+	case VBG_IOCTL_DRIVER_VERSION_INFO:
+		return vbg_ioctl_driver_version_info(data);
+	case VBG_IOCTL_HGCM_CONNECT:
+		return vbg_ioctl_hgcm_connect(gdev, session, data);
+	case VBG_IOCTL_HGCM_DISCONNECT:
+		return vbg_ioctl_hgcm_disconnect(gdev, session, data);
+	case VBG_IOCTL_WAIT_FOR_EVENTS:
+		return vbg_ioctl_wait_for_events(gdev, session, data);
+	case VBG_IOCTL_INTERRUPT_ALL_WAIT_FOR_EVENTS:
+		return vbg_ioctl_interrupt_all_wait_events(gdev, session, data);
+	case VBG_IOCTL_CHANGE_FILTER_MASK:
+		return vbg_ioctl_change_filter_mask(gdev, session, data);
+	case VBG_IOCTL_ACQUIRE_GUEST_CAPABILITIES:
+		return vbg_ioctl_acquire_guest_capabilities(gdev, session, data);
+	case VBG_IOCTL_CHANGE_GUEST_CAPABILITIES:
+		return vbg_ioctl_change_guest_capabilities(gdev, session, data);
+	case VBG_IOCTL_CHECK_BALLOON:
+		return vbg_ioctl_check_balloon(gdev, data);
+	case VBG_IOCTL_WRITE_CORE_DUMP:
+		return vbg_ioctl_write_core_dump(gdev, session, data);
+	}
+
+	/* Variable sized requests. */
+	switch (req_no_size) {
+#ifdef CONFIG_COMPAT
+	case VBG_IOCTL_HGCM_CALL_32(0):
+		f32bit = true;
+		fallthrough;
+#endif
+	case VBG_IOCTL_HGCM_CALL(0):
+		return vbg_ioctl_hgcm_call(gdev, session, f32bit, data);
+	case VBG_IOCTL_LOG(0):
+	case VBG_IOCTL_LOG_ALT(0):
+		return vbg_ioctl_log(data);
+	}
+
+	vbg_err_ratelimited("Userspace made an unknown ioctl req %#08x\n", req);
+	return -ENOTTY;
+}
+
+/**
+ * Report guest supported mouse-features to the host.
+ *
+ * Return: 0 or negative errno value.
+ * @gdev:		The Guest extension device.
+ * @features:		The set of features to report to the host.
+ */
+int vbg_core_set_mouse_status(struct vbg_dev *gdev, u32 features)
+{
+	struct vmmdev_mouse_status *req;
+	int rc;
+
+	req = vbg_req_alloc(sizeof(*req), VMMDEVREQ_SET_MOUSE_STATUS,
+			    VBG_KERNEL_REQUEST);
+	if (!req)
+		return -ENOMEM;
+
+	req->mouse_features = features;
+	req->pointer_pos_x = 0;
+	req->pointer_pos_y = 0;
+
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0)
+		vbg_err("%s error, rc: %d\n", __func__, rc);
+
+	vbg_req_free(req, sizeof(*req));
+	return vbg_status_code_to_errno(rc);
+}
+
+/** Core interrupt service routine. */
+irqreturn_t vbg_core_isr(int irq, void *dev_id)
+{
+	struct vbg_dev *gdev = dev_id;
+	struct vmmdev_events *req = gdev->ack_events_req;
+	bool mouse_position_changed = false;
+	unsigned long flags;
+	u32 events = 0;
+	int rc;
+
+	if (!gdev->mmio->V.V1_04.have_events)
+		return IRQ_NONE;
+
+	/* Get and acknowlegde events. */
+	req->header.rc = VERR_INTERNAL_ERROR;
+	req->events = 0;
+	rc = vbg_req_perform(gdev, req);
+	if (rc < 0) {
+		vbg_err("Error performing events req, rc: %d\n", rc);
+		return IRQ_NONE;
+	}
+
+	events = req->events;
+
+	if (events & VMMDEV_EVENT_MOUSE_POSITION_CHANGED) {
+		mouse_position_changed = true;
+		events &= ~VMMDEV_EVENT_MOUSE_POSITION_CHANGED;
+	}
+
+	if (events & VMMDEV_EVENT_HGCM) {
+		wake_up(&gdev->hgcm_wq);
+		events &= ~VMMDEV_EVENT_HGCM;
+	}
+
+	if (events & VMMDEV_EVENT_BALLOON_CHANGE_REQUEST) {
+		schedule_work(&gdev->mem_balloon.work);
+		events &= ~VMMDEV_EVENT_BALLOON_CHANGE_REQUEST;
+	}
+
+	if (events) {
+		spin_lock_irqsave(&gdev->event_spinlock, flags);
+		gdev->pending_events |= events;
+		spin_unlock_irqrestore(&gdev->event_spinlock, flags);
+
+		wake_up(&gdev->event_wq);
+	}
+
+	if (mouse_position_changed)
+		vbg_linux_mouse_event(gdev);
+
+	return IRQ_HANDLED;
+}
diff --git a/drivers/virt/vboxguest/vboxguest_core.h b/drivers/virt/vboxguest/vboxguest_core.h
new file mode 100644
index 000000000..ab4bf64e2
--- /dev/null
+++ b/drivers/virt/vboxguest/vboxguest_core.h
@@ -0,0 +1,214 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
+/* Copyright (C) 2010-2016 Oracle Corporation */
+
+#ifndef __VBOXGUEST_CORE_H__
+#define __VBOXGUEST_CORE_H__
+
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/vboxguest.h>
+#include "vmmdev.h"
+
+/*
+ * The mainline kernel version (this version) of the vboxguest module
+ * contained a bug where it defined VBGL_IOCTL_VMMDEV_REQUEST_BIG and
+ * VBGL_IOCTL_LOG using _IOC(_IOC_READ | _IOC_WRITE, 'V', ...) instead
+ * of _IO(V, ...) as the out of tree VirtualBox upstream version does.
+ *
+ * These _ALT definitions keep compatibility with the wrong defines the
+ * mainline kernel version used for a while.
+ * Note the VirtualBox userspace bits have always been built against
+ * VirtualBox upstream's headers, so this is likely not necessary. But
+ * we must never break our ABI so we keep these around to be 100% sure.
+ */
+#define VBG_IOCTL_VMMDEV_REQUEST_BIG_ALT _IOC(_IOC_READ | _IOC_WRITE, 'V', 3, 0)
+#define VBG_IOCTL_LOG_ALT(s)             _IOC(_IOC_READ | _IOC_WRITE, 'V', 9, s)
+
+struct vbg_session;
+
+/** VBox guest memory balloon. */
+struct vbg_mem_balloon {
+	/** Work handling VMMDEV_EVENT_BALLOON_CHANGE_REQUEST events */
+	struct work_struct work;
+	/** Pre-allocated vmmdev_memballoon_info req for query */
+	struct vmmdev_memballoon_info *get_req;
+	/** Pre-allocated vmmdev_memballoon_change req for inflate / deflate */
+	struct vmmdev_memballoon_change *change_req;
+	/** The current number of chunks in the balloon. */
+	u32 chunks;
+	/** The maximum number of chunks in the balloon. */
+	u32 max_chunks;
+	/**
+	 * Array of pointers to page arrays. A page * array is allocated for
+	 * each chunk when inflating, and freed when the deflating.
+	 */
+	struct page ***pages;
+};
+
+/**
+ * Per bit usage tracker for a u32 mask.
+ *
+ * Used for optimal handling of guest properties and event filter.
+ */
+struct vbg_bit_usage_tracker {
+	/** Per bit usage counters. */
+	u32 per_bit_usage[32];
+	/** The current mask according to per_bit_usage. */
+	u32 mask;
+};
+
+/** VBox guest device (data) extension. */
+struct vbg_dev {
+	struct device *dev;
+	/** The base of the adapter I/O ports. */
+	u16 io_port;
+	/** Pointer to the mapping of the VMMDev adapter memory. */
+	struct vmmdev_memory *mmio;
+	/** Host version */
+	char host_version[64];
+	/** Host features */
+	unsigned int host_features;
+	/**
+	 * Dummy page and vmap address for reserved kernel virtual-address
+	 * space for the guest mappings, only used on hosts lacking vtx.
+	 */
+	struct page *guest_mappings_dummy_page;
+	void *guest_mappings;
+	/** Spinlock protecting pending_events. */
+	spinlock_t event_spinlock;
+	/** Preallocated struct vmmdev_events for the IRQ handler. */
+	struct vmmdev_events *ack_events_req;
+	/** Wait-for-event list for threads waiting for multiple events. */
+	wait_queue_head_t event_wq;
+	/** Mask of pending events. */
+	u32 pending_events;
+	/** Wait-for-event list for threads waiting on HGCM async completion. */
+	wait_queue_head_t hgcm_wq;
+	/** Pre-allocated hgcm cancel2 req. for cancellation on timeout */
+	struct vmmdev_hgcm_cancel2 *cancel_req;
+	/** Mutex protecting cancel_req accesses */
+	struct mutex cancel_req_mutex;
+	/** Pre-allocated mouse-status request for the input-device handling. */
+	struct vmmdev_mouse_status *mouse_status_req;
+	/** Input device for reporting abs mouse coordinates to the guest. */
+	struct input_dev *input;
+
+	/** Memory balloon information. */
+	struct vbg_mem_balloon mem_balloon;
+
+	/** Lock for session related items in vbg_dev and vbg_session */
+	struct mutex session_mutex;
+	/** Events we won't permit anyone to filter out. */
+	u32 fixed_events;
+	/**
+	 * Usage counters for the host events (excludes fixed events),
+	 * Protected by session_mutex.
+	 */
+	struct vbg_bit_usage_tracker event_filter_tracker;
+	/**
+	 * The event filter last reported to the host (or UINT32_MAX).
+	 * Protected by session_mutex.
+	 */
+	u32 event_filter_host;
+
+	/**
+	 * Guest capabilities which have been switched to acquire_mode.
+	 */
+	u32 acquire_mode_guest_caps;
+	/**
+	 * Guest capabilities acquired by vbg_acquire_session_capabilities().
+	 * Only one session can acquire a capability at a time.
+	 */
+	u32 acquired_guest_caps;
+	/**
+	 * Usage counters for guest capabilities requested through
+	 * vbg_set_session_capabilities(). Indexed by capability bit
+	 * number, one count per session using a capability.
+	 * Protected by session_mutex.
+	 */
+	struct vbg_bit_usage_tracker set_guest_caps_tracker;
+	/**
+	 * The guest capabilities last reported to the host (or UINT32_MAX).
+	 * Protected by session_mutex.
+	 */
+	u32 guest_caps_host;
+
+	/**
+	 * Heartbeat timer which fires with interval
+	 * cNsHearbeatInterval and its handler sends
+	 * VMMDEVREQ_GUEST_HEARTBEAT to VMMDev.
+	 */
+	struct timer_list heartbeat_timer;
+	/** Heartbeat timer interval in ms. */
+	int heartbeat_interval_ms;
+	/** Preallocated VMMDEVREQ_GUEST_HEARTBEAT request. */
+	struct vmmdev_request_header *guest_heartbeat_req;
+
+	/** "vboxguest" char-device */
+	struct miscdevice misc_device;
+	/** "vboxuser" char-device */
+	struct miscdevice misc_device_user;
+};
+
+/** The VBoxGuest per session data. */
+struct vbg_session {
+	/** Pointer to the device extension. */
+	struct vbg_dev *gdev;
+
+	/**
+	 * Array containing HGCM client IDs associated with this session.
+	 * These will be automatically disconnected when the session is closed.
+	 * Protected by vbg_gdev.session_mutex.
+	 */
+	u32 hgcm_client_ids[64];
+	/**
+	 * Host events requested by the session.
+	 * An event type requested in any guest session will be added to the
+	 * host filter. Protected by vbg_gdev.session_mutex.
+	 */
+	u32 event_filter;
+	/**
+	 * Guest capabilities acquired by vbg_acquire_session_capabilities().
+	 * Only one session can acquire a capability at a time.
+	 */
+	u32 acquired_guest_caps;
+	/**
+	 * Guest capabilities set through vbg_set_session_capabilities().
+	 * A capability claimed by any guest session will be reported to the
+	 * host. Protected by vbg_gdev.session_mutex.
+	 */
+	u32 set_guest_caps;
+	/** VMMDEV_REQUESTOR_* flags */
+	u32 requestor;
+	/** Set on CANCEL_ALL_WAITEVENTS, protected by vbg_devevent_spinlock. */
+	bool cancel_waiters;
+};
+
+int  vbg_core_init(struct vbg_dev *gdev, u32 fixed_events);
+void vbg_core_exit(struct vbg_dev *gdev);
+struct vbg_session *vbg_core_open_session(struct vbg_dev *gdev, u32 requestor);
+void vbg_core_close_session(struct vbg_session *session);
+int  vbg_core_ioctl(struct vbg_session *session, unsigned int req, void *data);
+int  vbg_core_set_mouse_status(struct vbg_dev *gdev, u32 features);
+
+irqreturn_t vbg_core_isr(int irq, void *dev_id);
+
+void vbg_linux_mouse_event(struct vbg_dev *gdev);
+
+/* Private (non exported) functions form vboxguest_utils.c */
+void *vbg_req_alloc(size_t len, enum vmmdev_request_type req_type,
+		    u32 requestor);
+void vbg_req_free(void *req, size_t len);
+int vbg_req_perform(struct vbg_dev *gdev, void *req);
+int vbg_hgcm_call32(
+	struct vbg_dev *gdev, u32 requestor, u32 client_id, u32 function,
+	u32 timeout_ms, struct vmmdev_hgcm_function_parameter32 *parm32,
+	u32 parm_count, int *vbox_status);
+
+#endif
diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
new file mode 100644
index 000000000..4ccfd30c2
--- /dev/null
+++ b/drivers/virt/vboxguest/vboxguest_linux.c
@@ -0,0 +1,500 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * vboxguest linux pci driver, char-dev and input-device code,
+ *
+ * Copyright (C) 2006-2016 Oracle Corporation
+ */
+
+#include <linux/cred.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/poll.h>
+#include <linux/vbox_utils.h>
+#include "vboxguest_core.h"
+
+/** The device name. */
+#define DEVICE_NAME		"vboxguest"
+/** The device name for the device node open to everyone. */
+#define DEVICE_NAME_USER	"vboxuser"
+/** VirtualBox PCI vendor ID. */
+#define VBOX_VENDORID		0x80ee
+/** VMMDev PCI card product ID. */
+#define VMMDEV_DEVICEID		0xcafe
+
+/** Mutex protecting the global vbg_gdev pointer used by vbg_get/put_gdev. */
+static DEFINE_MUTEX(vbg_gdev_mutex);
+/** Global vbg_gdev pointer used by vbg_get/put_gdev. */
+static struct vbg_dev *vbg_gdev;
+
+static u32 vbg_misc_device_requestor(struct inode *inode)
+{
+	u32 requestor = VMMDEV_REQUESTOR_USERMODE |
+			VMMDEV_REQUESTOR_CON_DONT_KNOW |
+			VMMDEV_REQUESTOR_TRUST_NOT_GIVEN;
+
+	if (from_kuid(current_user_ns(), current_uid()) == 0)
+		requestor |= VMMDEV_REQUESTOR_USR_ROOT;
+	else
+		requestor |= VMMDEV_REQUESTOR_USR_USER;
+
+	if (in_egroup_p(inode->i_gid))
+		requestor |= VMMDEV_REQUESTOR_GRP_VBOX;
+
+	return requestor;
+}
+
+static int vbg_misc_device_open(struct inode *inode, struct file *filp)
+{
+	struct vbg_session *session;
+	struct vbg_dev *gdev;
+
+	/* misc_open sets filp->private_data to our misc device */
+	gdev = container_of(filp->private_data, struct vbg_dev, misc_device);
+
+	session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode));
+	if (IS_ERR(session))
+		return PTR_ERR(session);
+
+	filp->private_data = session;
+	return 0;
+}
+
+static int vbg_misc_device_user_open(struct inode *inode, struct file *filp)
+{
+	struct vbg_session *session;
+	struct vbg_dev *gdev;
+
+	/* misc_open sets filp->private_data to our misc device */
+	gdev = container_of(filp->private_data, struct vbg_dev,
+			    misc_device_user);
+
+	session = vbg_core_open_session(gdev, vbg_misc_device_requestor(inode) |
+					      VMMDEV_REQUESTOR_USER_DEVICE);
+	if (IS_ERR(session))
+		return PTR_ERR(session);
+
+	filp->private_data = session;
+	return 0;
+}
+
+/**
+ * Close device.
+ * Return: 0 on success, negated errno on failure.
+ * @inode:		Pointer to inode info structure.
+ * @filp:		Associated file pointer.
+ */
+static int vbg_misc_device_close(struct inode *inode, struct file *filp)
+{
+	vbg_core_close_session(filp->private_data);
+	filp->private_data = NULL;
+	return 0;
+}
+
+/**
+ * Device I/O Control entry point.
+ * Return: 0 on success, negated errno on failure.
+ * @filp:		Associated file pointer.
+ * @req:		The request specified to ioctl().
+ * @arg:		The argument specified to ioctl().
+ */
+static long vbg_misc_device_ioctl(struct file *filp, unsigned int req,
+				  unsigned long arg)
+{
+	struct vbg_session *session = filp->private_data;
+	size_t returned_size, size;
+	struct vbg_ioctl_hdr hdr;
+	bool is_vmmdev_req;
+	int ret = 0;
+	void *buf;
+
+	if (copy_from_user(&hdr, (void *)arg, sizeof(hdr)))
+		return -EFAULT;
+
+	if (hdr.version != VBG_IOCTL_HDR_VERSION)
+		return -EINVAL;
+
+	if (hdr.size_in < sizeof(hdr) ||
+	    (hdr.size_out && hdr.size_out < sizeof(hdr)))
+		return -EINVAL;
+
+	size = max(hdr.size_in, hdr.size_out);
+	if (_IOC_SIZE(req) && _IOC_SIZE(req) != size)
+		return -EINVAL;
+	if (size > SZ_16M)
+		return -E2BIG;
+
+	/*
+	 * IOCTL_VMMDEV_REQUEST needs the buffer to be below 4G to avoid
+	 * the need for a bounce-buffer and another copy later on.
+	 */
+	is_vmmdev_req = (req & ~IOCSIZE_MASK) == VBG_IOCTL_VMMDEV_REQUEST(0) ||
+			 req == VBG_IOCTL_VMMDEV_REQUEST_BIG ||
+			 req == VBG_IOCTL_VMMDEV_REQUEST_BIG_ALT;
+
+	if (is_vmmdev_req)
+		buf = vbg_req_alloc(size, VBG_IOCTL_HDR_TYPE_DEFAULT,
+				    session->requestor);
+	else
+		buf = kmalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	*((struct vbg_ioctl_hdr *)buf) = hdr;
+	if (copy_from_user(buf + sizeof(hdr), (void *)arg + sizeof(hdr),
+			   hdr.size_in - sizeof(hdr))) {
+		ret = -EFAULT;
+		goto out;
+	}
+	if (hdr.size_in < size)
+		memset(buf + hdr.size_in, 0, size -  hdr.size_in);
+
+	ret = vbg_core_ioctl(session, req, buf);
+	if (ret)
+		goto out;
+
+	returned_size = ((struct vbg_ioctl_hdr *)buf)->size_out;
+	if (returned_size > size) {
+		vbg_debug("%s: too much output data %zu > %zu\n",
+			  __func__, returned_size, size);
+		returned_size = size;
+	}
+	if (copy_to_user((void *)arg, buf, returned_size) != 0)
+		ret = -EFAULT;
+
+out:
+	if (is_vmmdev_req)
+		vbg_req_free(buf, size);
+	else
+		kfree(buf);
+
+	return ret;
+}
+
+/** The file_operations structures. */
+static const struct file_operations vbg_misc_device_fops = {
+	.owner			= THIS_MODULE,
+	.open			= vbg_misc_device_open,
+	.release		= vbg_misc_device_close,
+	.unlocked_ioctl		= vbg_misc_device_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= vbg_misc_device_ioctl,
+#endif
+};
+static const struct file_operations vbg_misc_device_user_fops = {
+	.owner			= THIS_MODULE,
+	.open			= vbg_misc_device_user_open,
+	.release		= vbg_misc_device_close,
+	.unlocked_ioctl		= vbg_misc_device_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= vbg_misc_device_ioctl,
+#endif
+};
+
+/**
+ * Called when the input device is first opened.
+ *
+ * Sets up absolute mouse reporting.
+ */
+static int vbg_input_open(struct input_dev *input)
+{
+	struct vbg_dev *gdev = input_get_drvdata(input);
+	u32 feat = VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE | VMMDEV_MOUSE_NEW_PROTOCOL;
+
+	return vbg_core_set_mouse_status(gdev, feat);
+}
+
+/**
+ * Called if all open handles to the input device are closed.
+ *
+ * Disables absolute reporting.
+ */
+static void vbg_input_close(struct input_dev *input)
+{
+	struct vbg_dev *gdev = input_get_drvdata(input);
+
+	vbg_core_set_mouse_status(gdev, 0);
+}
+
+/**
+ * Creates the kernel input device.
+ *
+ * Return: 0 on success, negated errno on failure.
+ */
+static int vbg_create_input_device(struct vbg_dev *gdev)
+{
+	struct input_dev *input;
+
+	input = devm_input_allocate_device(gdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	input->id.bustype = BUS_PCI;
+	input->id.vendor = VBOX_VENDORID;
+	input->id.product = VMMDEV_DEVICEID;
+	input->open = vbg_input_open;
+	input->close = vbg_input_close;
+	input->dev.parent = gdev->dev;
+	input->name = "VirtualBox mouse integration";
+
+	input_set_abs_params(input, ABS_X, VMMDEV_MOUSE_RANGE_MIN,
+			     VMMDEV_MOUSE_RANGE_MAX, 0, 0);
+	input_set_abs_params(input, ABS_Y, VMMDEV_MOUSE_RANGE_MIN,
+			     VMMDEV_MOUSE_RANGE_MAX, 0, 0);
+	input_set_capability(input, EV_KEY, BTN_MOUSE);
+	input_set_drvdata(input, gdev);
+
+	gdev->input = input;
+
+	return input_register_device(gdev->input);
+}
+
+static ssize_t host_version_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct vbg_dev *gdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", gdev->host_version);
+}
+
+static ssize_t host_features_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct vbg_dev *gdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%#x\n", gdev->host_features);
+}
+
+static DEVICE_ATTR_RO(host_version);
+static DEVICE_ATTR_RO(host_features);
+
+/**
+ * Does the PCI detection and init of the device.
+ *
+ * Return: 0 on success, negated errno on failure.
+ */
+static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
+{
+	struct device *dev = &pci->dev;
+	resource_size_t io, io_len, mmio, mmio_len;
+	struct vmmdev_memory *vmmdev;
+	struct vbg_dev *gdev;
+	int ret;
+
+	gdev = devm_kzalloc(dev, sizeof(*gdev), GFP_KERNEL);
+	if (!gdev)
+		return -ENOMEM;
+
+	ret = pci_enable_device(pci);
+	if (ret != 0) {
+		vbg_err("vboxguest: Error enabling device: %d\n", ret);
+		return ret;
+	}
+
+	ret = -ENODEV;
+
+	io = pci_resource_start(pci, 0);
+	io_len = pci_resource_len(pci, 0);
+	if (!io || !io_len) {
+		vbg_err("vboxguest: Error IO-port resource (0) is missing\n");
+		goto err_disable_pcidev;
+	}
+	if (devm_request_region(dev, io, io_len, DEVICE_NAME) == NULL) {
+		vbg_err("vboxguest: Error could not claim IO resource\n");
+		ret = -EBUSY;
+		goto err_disable_pcidev;
+	}
+
+	mmio = pci_resource_start(pci, 1);
+	mmio_len = pci_resource_len(pci, 1);
+	if (!mmio || !mmio_len) {
+		vbg_err("vboxguest: Error MMIO resource (1) is missing\n");
+		goto err_disable_pcidev;
+	}
+
+	if (devm_request_mem_region(dev, mmio, mmio_len, DEVICE_NAME) == NULL) {
+		vbg_err("vboxguest: Error could not claim MMIO resource\n");
+		ret = -EBUSY;
+		goto err_disable_pcidev;
+	}
+
+	vmmdev = devm_ioremap(dev, mmio, mmio_len);
+	if (!vmmdev) {
+		vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
+			&mmio, &mmio_len);
+		goto err_disable_pcidev;
+	}
+
+	/* Validate MMIO region version and size. */
+	if (vmmdev->version != VMMDEV_MEMORY_VERSION ||
+	    vmmdev->size < 32 || vmmdev->size > mmio_len) {
+		vbg_err("vboxguest: Bogus VMMDev memory; version=%08x (expected %08x) size=%d (expected <= %d)\n",
+			vmmdev->version, VMMDEV_MEMORY_VERSION,
+			vmmdev->size, (int)mmio_len);
+		goto err_disable_pcidev;
+	}
+
+	gdev->io_port = io;
+	gdev->mmio = vmmdev;
+	gdev->dev = dev;
+	gdev->misc_device.minor = MISC_DYNAMIC_MINOR;
+	gdev->misc_device.name = DEVICE_NAME;
+	gdev->misc_device.fops = &vbg_misc_device_fops;
+	gdev->misc_device_user.minor = MISC_DYNAMIC_MINOR;
+	gdev->misc_device_user.name = DEVICE_NAME_USER;
+	gdev->misc_device_user.fops = &vbg_misc_device_user_fops;
+
+	ret = vbg_core_init(gdev, VMMDEV_EVENT_MOUSE_POSITION_CHANGED);
+	if (ret)
+		goto err_disable_pcidev;
+
+	ret = vbg_create_input_device(gdev);
+	if (ret) {
+		vbg_err("vboxguest: Error creating input device: %d\n", ret);
+		goto err_vbg_core_exit;
+	}
+
+	ret = request_irq(pci->irq, vbg_core_isr, IRQF_SHARED, DEVICE_NAME,
+			  gdev);
+	if (ret) {
+		vbg_err("vboxguest: Error requesting irq: %d\n", ret);
+		goto err_vbg_core_exit;
+	}
+
+	ret = misc_register(&gdev->misc_device);
+	if (ret) {
+		vbg_err("vboxguest: Error misc_register %s failed: %d\n",
+			DEVICE_NAME, ret);
+		goto err_free_irq;
+	}
+
+	ret = misc_register(&gdev->misc_device_user);
+	if (ret) {
+		vbg_err("vboxguest: Error misc_register %s failed: %d\n",
+			DEVICE_NAME_USER, ret);
+		goto err_unregister_misc_device;
+	}
+
+	mutex_lock(&vbg_gdev_mutex);
+	if (!vbg_gdev)
+		vbg_gdev = gdev;
+	else
+		ret = -EBUSY;
+	mutex_unlock(&vbg_gdev_mutex);
+
+	if (ret) {
+		vbg_err("vboxguest: Error more then 1 vbox guest pci device\n");
+		goto err_unregister_misc_device_user;
+	}
+
+	pci_set_drvdata(pci, gdev);
+	device_create_file(dev, &dev_attr_host_version);
+	device_create_file(dev, &dev_attr_host_features);
+
+	vbg_info("vboxguest: misc device minor %d, IRQ %d, I/O port %x, MMIO at %pap (size %pap)\n",
+		 gdev->misc_device.minor, pci->irq, gdev->io_port,
+		 &mmio, &mmio_len);
+
+	return 0;
+
+err_unregister_misc_device_user:
+	misc_deregister(&gdev->misc_device_user);
+err_unregister_misc_device:
+	misc_deregister(&gdev->misc_device);
+err_free_irq:
+	free_irq(pci->irq, gdev);
+err_vbg_core_exit:
+	vbg_core_exit(gdev);
+err_disable_pcidev:
+	pci_disable_device(pci);
+
+	return ret;
+}
+
+static void vbg_pci_remove(struct pci_dev *pci)
+{
+	struct vbg_dev *gdev = pci_get_drvdata(pci);
+
+	mutex_lock(&vbg_gdev_mutex);
+	vbg_gdev = NULL;
+	mutex_unlock(&vbg_gdev_mutex);
+
+	free_irq(pci->irq, gdev);
+	device_remove_file(gdev->dev, &dev_attr_host_features);
+	device_remove_file(gdev->dev, &dev_attr_host_version);
+	misc_deregister(&gdev->misc_device_user);
+	misc_deregister(&gdev->misc_device);
+	vbg_core_exit(gdev);
+	pci_disable_device(pci);
+}
+
+struct vbg_dev *vbg_get_gdev(void)
+{
+	mutex_lock(&vbg_gdev_mutex);
+
+	/*
+	 * Note on success we keep the mutex locked until vbg_put_gdev(),
+	 * this stops vbg_pci_remove from removing the device from underneath
+	 * vboxsf. vboxsf will only hold a reference for a short while.
+	 */
+	if (vbg_gdev)
+		return vbg_gdev;
+
+	mutex_unlock(&vbg_gdev_mutex);
+	return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL(vbg_get_gdev);
+
+void vbg_put_gdev(struct vbg_dev *gdev)
+{
+	WARN_ON(gdev != vbg_gdev);
+	mutex_unlock(&vbg_gdev_mutex);
+}
+EXPORT_SYMBOL(vbg_put_gdev);
+
+/**
+ * Callback for mouse events.
+ *
+ * This is called at the end of the ISR, after leaving the event spinlock, if
+ * VMMDEV_EVENT_MOUSE_POSITION_CHANGED was raised by the host.
+ *
+ * @gdev:		The device extension.
+ */
+void vbg_linux_mouse_event(struct vbg_dev *gdev)
+{
+	int rc;
+
+	/* Report events to the kernel input device */
+	gdev->mouse_status_req->mouse_features = 0;
+	gdev->mouse_status_req->pointer_pos_x = 0;
+	gdev->mouse_status_req->pointer_pos_y = 0;
+	rc = vbg_req_perform(gdev, gdev->mouse_status_req);
+	if (rc >= 0) {
+		input_report_abs(gdev->input, ABS_X,
+				 gdev->mouse_status_req->pointer_pos_x);
+		input_report_abs(gdev->input, ABS_Y,
+				 gdev->mouse_status_req->pointer_pos_y);
+		input_sync(gdev->input);
+	}
+}
+
+static const struct pci_device_id vbg_pci_ids[] = {
+	{ .vendor = VBOX_VENDORID, .device = VMMDEV_DEVICEID },
+	{}
+};
+MODULE_DEVICE_TABLE(pci,  vbg_pci_ids);
+
+static struct pci_driver vbg_pci_driver = {
+	.name		= DEVICE_NAME,
+	.id_table	= vbg_pci_ids,
+	.probe		= vbg_pci_probe,
+	.remove		= vbg_pci_remove,
+};
+
+module_pci_driver(vbg_pci_driver);
+
+MODULE_AUTHOR("Oracle Corporation");
+MODULE_DESCRIPTION("Oracle VM VirtualBox Guest Additions for Linux Module");
+MODULE_LICENSE("GPL");
diff --git a/drivers/virt/vboxguest/vboxguest_utils.c b/drivers/virt/vboxguest/vboxguest_utils.c
new file mode 100644
index 000000000..8d195e3f8
--- /dev/null
+++ b/drivers/virt/vboxguest/vboxguest_utils.c
@@ -0,0 +1,825 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
+/*
+ * vboxguest vmm-req and hgcm-call code, VBoxGuestR0LibHGCMInternal.cpp,
+ * VBoxGuestR0LibGenericRequest.cpp and RTErrConvertToErrno.cpp in vbox svn.
+ *
+ * Copyright (C) 2006-2016 Oracle Corporation
+ */
+
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/vbox_err.h>
+#include <linux/vbox_utils.h>
+#include "vboxguest_core.h"
+
+/* Get the pointer to the first parameter of a HGCM call request. */
+#define VMMDEV_HGCM_CALL_PARMS(a) \
+	((struct vmmdev_hgcm_function_parameter *)( \
+		(u8 *)(a) + sizeof(struct vmmdev_hgcm_call)))
+
+/* The max parameter buffer size for a user request. */
+#define VBG_MAX_HGCM_USER_PARM		(24 * SZ_1M)
+/* The max parameter buffer size for a kernel request. */
+#define VBG_MAX_HGCM_KERNEL_PARM	(16 * SZ_1M)
+
+#define VBG_DEBUG_PORT			0x504
+
+/* This protects vbg_log_buf and serializes VBG_DEBUG_PORT accesses */
+static DEFINE_SPINLOCK(vbg_log_lock);
+static char vbg_log_buf[128];
+
+#define VBG_LOG(name, pr_func) \
+void name(const char *fmt, ...)						\
+{									\
+	unsigned long flags;						\
+	va_list args;							\
+	int i, count;							\
+									\
+	va_start(args, fmt);						\
+	spin_lock_irqsave(&vbg_log_lock, flags);			\
+									\
+	count = vscnprintf(vbg_log_buf, sizeof(vbg_log_buf), fmt, args);\
+	for (i = 0; i < count; i++)					\
+		outb(vbg_log_buf[i], VBG_DEBUG_PORT);			\
+									\
+	pr_func("%s", vbg_log_buf);					\
+									\
+	spin_unlock_irqrestore(&vbg_log_lock, flags);			\
+	va_end(args);							\
+}									\
+EXPORT_SYMBOL(name)
+
+VBG_LOG(vbg_info, pr_info);
+VBG_LOG(vbg_warn, pr_warn);
+VBG_LOG(vbg_err, pr_err);
+VBG_LOG(vbg_err_ratelimited, pr_err_ratelimited);
+#if defined(DEBUG) && !defined(CONFIG_DYNAMIC_DEBUG)
+VBG_LOG(vbg_debug, pr_debug);
+#endif
+
+void *vbg_req_alloc(size_t len, enum vmmdev_request_type req_type,
+		    u32 requestor)
+{
+	struct vmmdev_request_header *req;
+	int order = get_order(PAGE_ALIGN(len));
+
+	req = (void *)__get_free_pages(GFP_KERNEL | GFP_DMA32, order);
+	if (!req)
+		return NULL;
+
+	memset(req, 0xaa, len);
+
+	req->size = len;
+	req->version = VMMDEV_REQUEST_HEADER_VERSION;
+	req->request_type = req_type;
+	req->rc = VERR_GENERAL_FAILURE;
+	req->reserved1 = 0;
+	req->requestor = requestor;
+
+	return req;
+}
+
+void vbg_req_free(void *req, size_t len)
+{
+	if (!req)
+		return;
+
+	free_pages((unsigned long)req, get_order(PAGE_ALIGN(len)));
+}
+
+/* Note this function returns a VBox status code, not a negative errno!! */
+int vbg_req_perform(struct vbg_dev *gdev, void *req)
+{
+	unsigned long phys_req = virt_to_phys(req);
+
+	outl(phys_req, gdev->io_port + VMMDEV_PORT_OFF_REQUEST);
+	/*
+	 * The host changes the request as a result of the outl, make sure
+	 * the outl and any reads of the req happen in the correct order.
+	 */
+	mb();
+
+	return ((struct vmmdev_request_header *)req)->rc;
+}
+
+static bool hgcm_req_done(struct vbg_dev *gdev,
+			  struct vmmdev_hgcmreq_header *header)
+{
+	unsigned long flags;
+	bool done;
+
+	spin_lock_irqsave(&gdev->event_spinlock, flags);
+	done = header->flags & VMMDEV_HGCM_REQ_DONE;
+	spin_unlock_irqrestore(&gdev->event_spinlock, flags);
+
+	return done;
+}
+
+int vbg_hgcm_connect(struct vbg_dev *gdev, u32 requestor,
+		     struct vmmdev_hgcm_service_location *loc,
+		     u32 *client_id, int *vbox_status)
+{
+	struct vmmdev_hgcm_connect *hgcm_connect = NULL;
+	int rc;
+
+	hgcm_connect = vbg_req_alloc(sizeof(*hgcm_connect),
+				     VMMDEVREQ_HGCM_CONNECT, requestor);
+	if (!hgcm_connect)
+		return -ENOMEM;
+
+	hgcm_connect->header.flags = 0;
+	memcpy(&hgcm_connect->loc, loc, sizeof(*loc));
+	hgcm_connect->client_id = 0;
+
+	rc = vbg_req_perform(gdev, hgcm_connect);
+
+	if (rc == VINF_HGCM_ASYNC_EXECUTE)
+		wait_event(gdev->hgcm_wq,
+			   hgcm_req_done(gdev, &hgcm_connect->header));
+
+	if (rc >= 0) {
+		*client_id = hgcm_connect->client_id;
+		rc = hgcm_connect->header.result;
+	}
+
+	vbg_req_free(hgcm_connect, sizeof(*hgcm_connect));
+
+	*vbox_status = rc;
+	return 0;
+}
+EXPORT_SYMBOL(vbg_hgcm_connect);
+
+int vbg_hgcm_disconnect(struct vbg_dev *gdev, u32 requestor,
+			u32 client_id, int *vbox_status)
+{
+	struct vmmdev_hgcm_disconnect *hgcm_disconnect = NULL;
+	int rc;
+
+	hgcm_disconnect = vbg_req_alloc(sizeof(*hgcm_disconnect),
+					VMMDEVREQ_HGCM_DISCONNECT,
+					requestor);
+	if (!hgcm_disconnect)
+		return -ENOMEM;
+
+	hgcm_disconnect->header.flags = 0;
+	hgcm_disconnect->client_id = client_id;
+
+	rc = vbg_req_perform(gdev, hgcm_disconnect);
+
+	if (rc == VINF_HGCM_ASYNC_EXECUTE)
+		wait_event(gdev->hgcm_wq,
+			   hgcm_req_done(gdev, &hgcm_disconnect->header));
+
+	if (rc >= 0)
+		rc = hgcm_disconnect->header.result;
+
+	vbg_req_free(hgcm_disconnect, sizeof(*hgcm_disconnect));
+
+	*vbox_status = rc;
+	return 0;
+}
+EXPORT_SYMBOL(vbg_hgcm_disconnect);
+
+static u32 hgcm_call_buf_size_in_pages(void *buf, u32 len)
+{
+	u32 size = PAGE_ALIGN(len + ((unsigned long)buf & ~PAGE_MASK));
+
+	return size >> PAGE_SHIFT;
+}
+
+static void hgcm_call_add_pagelist_size(void *buf, u32 len, size_t *extra)
+{
+	u32 page_count;
+
+	page_count = hgcm_call_buf_size_in_pages(buf, len);
+	*extra += offsetof(struct vmmdev_hgcm_pagelist, pages[page_count]);
+}
+
+static int hgcm_call_preprocess_linaddr(
+	const struct vmmdev_hgcm_function_parameter *src_parm,
+	void **bounce_buf_ret, size_t *extra)
+{
+	void *buf, *bounce_buf;
+	bool copy_in;
+	u32 len;
+	int ret;
+
+	buf = (void *)src_parm->u.pointer.u.linear_addr;
+	len = src_parm->u.pointer.size;
+	copy_in = src_parm->type != VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT;
+
+	if (len > VBG_MAX_HGCM_USER_PARM)
+		return -E2BIG;
+
+	bounce_buf = kvmalloc(len, GFP_KERNEL);
+	if (!bounce_buf)
+		return -ENOMEM;
+
+	*bounce_buf_ret = bounce_buf;
+
+	if (copy_in) {
+		ret = copy_from_user(bounce_buf, (void __user *)buf, len);
+		if (ret)
+			return -EFAULT;
+	} else {
+		memset(bounce_buf, 0, len);
+	}
+
+	hgcm_call_add_pagelist_size(bounce_buf, len, extra);
+	return 0;
+}
+
+/**
+ * Preprocesses the HGCM call, validate parameters, alloc bounce buffers and
+ * figure out how much extra storage we need for page lists.
+ * Return: 0 or negative errno value.
+ * @src_parm:         Pointer to source function call parameters
+ * @parm_count:       Number of function call parameters.
+ * @bounce_bufs_ret:  Where to return the allocated bouncebuffer array
+ * @extra:            Where to return the extra request space needed for
+ *                    physical page lists.
+ */
+static int hgcm_call_preprocess(
+	const struct vmmdev_hgcm_function_parameter *src_parm,
+	u32 parm_count, void ***bounce_bufs_ret, size_t *extra)
+{
+	void *buf, **bounce_bufs = NULL;
+	u32 i, len;
+	int ret;
+
+	for (i = 0; i < parm_count; i++, src_parm++) {
+		switch (src_parm->type) {
+		case VMMDEV_HGCM_PARM_TYPE_32BIT:
+		case VMMDEV_HGCM_PARM_TYPE_64BIT:
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+			if (!bounce_bufs) {
+				bounce_bufs = kcalloc(parm_count,
+						      sizeof(void *),
+						      GFP_KERNEL);
+				if (!bounce_bufs)
+					return -ENOMEM;
+
+				*bounce_bufs_ret = bounce_bufs;
+			}
+
+			ret = hgcm_call_preprocess_linaddr(src_parm,
+							   &bounce_bufs[i],
+							   extra);
+			if (ret)
+				return ret;
+
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
+			buf = (void *)src_parm->u.pointer.u.linear_addr;
+			len = src_parm->u.pointer.size;
+			if (WARN_ON(len > VBG_MAX_HGCM_KERNEL_PARM))
+				return -E2BIG;
+
+			hgcm_call_add_pagelist_size(buf, len, extra);
+			break;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * Translates linear address types to page list direction flags.
+ *
+ * Return: page list flags.
+ * @type:  The type.
+ */
+static u32 hgcm_call_linear_addr_type_to_pagelist_flags(
+	enum vmmdev_hgcm_function_parameter_type type)
+{
+	switch (type) {
+	default:
+		WARN_ON(1);
+		fallthrough;
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
+		return VMMDEV_HGCM_F_PARM_DIRECTION_BOTH;
+
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
+		return VMMDEV_HGCM_F_PARM_DIRECTION_TO_HOST;
+
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
+		return VMMDEV_HGCM_F_PARM_DIRECTION_FROM_HOST;
+	}
+}
+
+static void hgcm_call_init_linaddr(struct vmmdev_hgcm_call *call,
+	struct vmmdev_hgcm_function_parameter *dst_parm, void *buf, u32 len,
+	enum vmmdev_hgcm_function_parameter_type type, u32 *off_extra)
+{
+	struct vmmdev_hgcm_pagelist *dst_pg_lst;
+	struct page *page;
+	bool is_vmalloc;
+	u32 i, page_count;
+
+	dst_parm->type = type;
+
+	if (len == 0) {
+		dst_parm->u.pointer.size = 0;
+		dst_parm->u.pointer.u.linear_addr = 0;
+		return;
+	}
+
+	dst_pg_lst = (void *)call + *off_extra;
+	page_count = hgcm_call_buf_size_in_pages(buf, len);
+	is_vmalloc = is_vmalloc_addr(buf);
+
+	dst_parm->type = VMMDEV_HGCM_PARM_TYPE_PAGELIST;
+	dst_parm->u.page_list.size = len;
+	dst_parm->u.page_list.offset = *off_extra;
+	dst_pg_lst->flags = hgcm_call_linear_addr_type_to_pagelist_flags(type);
+	dst_pg_lst->offset_first_page = (unsigned long)buf & ~PAGE_MASK;
+	dst_pg_lst->page_count = page_count;
+
+	for (i = 0; i < page_count; i++) {
+		if (is_vmalloc)
+			page = vmalloc_to_page(buf);
+		else
+			page = virt_to_page(buf);
+
+		dst_pg_lst->pages[i] = page_to_phys(page);
+		buf += PAGE_SIZE;
+	}
+
+	*off_extra += offsetof(struct vmmdev_hgcm_pagelist, pages[page_count]);
+}
+
+/**
+ * Initializes the call request that we're sending to the host.
+ * @call:            The call to initialize.
+ * @client_id:       The client ID of the caller.
+ * @function:        The function number of the function to call.
+ * @src_parm:        Pointer to source function call parameters.
+ * @parm_count:      Number of function call parameters.
+ * @bounce_bufs:     The bouncebuffer array.
+ */
+static void hgcm_call_init_call(
+	struct vmmdev_hgcm_call *call, u32 client_id, u32 function,
+	const struct vmmdev_hgcm_function_parameter *src_parm,
+	u32 parm_count, void **bounce_bufs)
+{
+	struct vmmdev_hgcm_function_parameter *dst_parm =
+		VMMDEV_HGCM_CALL_PARMS(call);
+	u32 i, off_extra = (uintptr_t)(dst_parm + parm_count) - (uintptr_t)call;
+	void *buf;
+
+	call->header.flags = 0;
+	call->header.result = VINF_SUCCESS;
+	call->client_id = client_id;
+	call->function = function;
+	call->parm_count = parm_count;
+
+	for (i = 0; i < parm_count; i++, src_parm++, dst_parm++) {
+		switch (src_parm->type) {
+		case VMMDEV_HGCM_PARM_TYPE_32BIT:
+		case VMMDEV_HGCM_PARM_TYPE_64BIT:
+			*dst_parm = *src_parm;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+			hgcm_call_init_linaddr(call, dst_parm, bounce_bufs[i],
+					       src_parm->u.pointer.size,
+					       src_parm->type, &off_extra);
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
+			buf = (void *)src_parm->u.pointer.u.linear_addr;
+			hgcm_call_init_linaddr(call, dst_parm, buf,
+					       src_parm->u.pointer.size,
+					       src_parm->type, &off_extra);
+			break;
+
+		default:
+			WARN_ON(1);
+			dst_parm->type = VMMDEV_HGCM_PARM_TYPE_INVALID;
+		}
+	}
+}
+
+/**
+ * Tries to cancel a pending HGCM call.
+ *
+ * Return: VBox status code
+ */
+static int hgcm_cancel_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call)
+{
+	int rc;
+
+	/*
+	 * We use a pre-allocated request for cancellations, which is
+	 * protected by cancel_req_mutex. This means that all cancellations
+	 * get serialized, this should be fine since they should be rare.
+	 */
+	mutex_lock(&gdev->cancel_req_mutex);
+	gdev->cancel_req->phys_req_to_cancel = virt_to_phys(call);
+	rc = vbg_req_perform(gdev, gdev->cancel_req);
+	mutex_unlock(&gdev->cancel_req_mutex);
+
+	if (rc == VERR_NOT_IMPLEMENTED) {
+		call->header.flags |= VMMDEV_HGCM_REQ_CANCELLED;
+		call->header.header.request_type = VMMDEVREQ_HGCM_CANCEL;
+
+		rc = vbg_req_perform(gdev, call);
+		if (rc == VERR_INVALID_PARAMETER)
+			rc = VERR_NOT_FOUND;
+	}
+
+	if (rc >= 0)
+		call->header.flags |= VMMDEV_HGCM_REQ_CANCELLED;
+
+	return rc;
+}
+
+/**
+ * Performs the call and completion wait.
+ * Return: 0 or negative errno value.
+ * @gdev:        The VBoxGuest device extension.
+ * @call:        The call to execute.
+ * @timeout_ms:  Timeout in ms.
+ * @leak_it:     Where to return the leak it / free it, indicator.
+ *               Cancellation fun.
+ */
+static int vbg_hgcm_do_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call,
+			    u32 timeout_ms, bool interruptible, bool *leak_it)
+{
+	int rc, cancel_rc, ret;
+	long timeout;
+
+	*leak_it = false;
+
+	rc = vbg_req_perform(gdev, call);
+
+	/*
+	 * If the call failed, then pretend success. Upper layers will
+	 * interpret the result code in the packet.
+	 */
+	if (rc < 0) {
+		call->header.result = rc;
+		return 0;
+	}
+
+	if (rc != VINF_HGCM_ASYNC_EXECUTE)
+		return 0;
+
+	/* Host decided to process the request asynchronously, wait for it */
+	if (timeout_ms == U32_MAX)
+		timeout = MAX_SCHEDULE_TIMEOUT;
+	else
+		timeout = msecs_to_jiffies(timeout_ms);
+
+	if (interruptible) {
+		timeout = wait_event_interruptible_timeout(gdev->hgcm_wq,
+							   hgcm_req_done(gdev, &call->header),
+							   timeout);
+	} else {
+		timeout = wait_event_timeout(gdev->hgcm_wq,
+					     hgcm_req_done(gdev, &call->header),
+					     timeout);
+	}
+
+	/* timeout > 0 means hgcm_req_done has returned true, so success */
+	if (timeout > 0)
+		return 0;
+
+	if (timeout == 0)
+		ret = -ETIMEDOUT;
+	else
+		ret = -EINTR;
+
+	/* Cancel the request */
+	cancel_rc = hgcm_cancel_call(gdev, call);
+	if (cancel_rc >= 0)
+		return ret;
+
+	/*
+	 * Failed to cancel, this should mean that the cancel has lost the
+	 * race with normal completion, wait while the host completes it.
+	 */
+	if (cancel_rc == VERR_NOT_FOUND || cancel_rc == VERR_SEM_DESTROYED)
+		timeout = msecs_to_jiffies(500);
+	else
+		timeout = msecs_to_jiffies(2000);
+
+	timeout = wait_event_timeout(gdev->hgcm_wq,
+				     hgcm_req_done(gdev, &call->header),
+				     timeout);
+
+	if (WARN_ON(timeout == 0)) {
+		/* We really should never get here */
+		vbg_err("%s: Call timedout and cancellation failed, leaking the request\n",
+			__func__);
+		*leak_it = true;
+		return ret;
+	}
+
+	/* The call has completed normally after all */
+	return 0;
+}
+
+/**
+ * Copies the result of the call back to the caller info structure and user
+ * buffers.
+ * Return: 0 or negative errno value.
+ * @call:            HGCM call request.
+ * @dst_parm:        Pointer to function call parameters destination.
+ * @parm_count:      Number of function call parameters.
+ * @bounce_bufs:     The bouncebuffer array.
+ */
+static int hgcm_call_copy_back_result(
+	const struct vmmdev_hgcm_call *call,
+	struct vmmdev_hgcm_function_parameter *dst_parm,
+	u32 parm_count, void **bounce_bufs)
+{
+	const struct vmmdev_hgcm_function_parameter *src_parm =
+		VMMDEV_HGCM_CALL_PARMS(call);
+	void __user *p;
+	int ret;
+	u32 i;
+
+	/* Copy back parameters. */
+	for (i = 0; i < parm_count; i++, src_parm++, dst_parm++) {
+		switch (dst_parm->type) {
+		case VMMDEV_HGCM_PARM_TYPE_32BIT:
+		case VMMDEV_HGCM_PARM_TYPE_64BIT:
+			*dst_parm = *src_parm;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_PAGELIST:
+			dst_parm->u.page_list.size = src_parm->u.page_list.size;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
+			dst_parm->u.pointer.size = src_parm->u.pointer.size;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+			dst_parm->u.pointer.size = src_parm->u.pointer.size;
+
+			p = (void __user *)dst_parm->u.pointer.u.linear_addr;
+			ret = copy_to_user(p, bounce_bufs[i],
+					   min(src_parm->u.pointer.size,
+					       dst_parm->u.pointer.size));
+			if (ret)
+				return -EFAULT;
+			break;
+
+		default:
+			WARN_ON(1);
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+int vbg_hgcm_call(struct vbg_dev *gdev, u32 requestor, u32 client_id,
+		  u32 function, u32 timeout_ms,
+		  struct vmmdev_hgcm_function_parameter *parms, u32 parm_count,
+		  int *vbox_status)
+{
+	struct vmmdev_hgcm_call *call;
+	void **bounce_bufs = NULL;
+	bool leak_it;
+	size_t size;
+	int i, ret;
+
+	size = sizeof(struct vmmdev_hgcm_call) +
+		   parm_count * sizeof(struct vmmdev_hgcm_function_parameter);
+	/*
+	 * Validate and buffer the parameters for the call. This also increases
+	 * call_size with the amount of extra space needed for page lists.
+	 */
+	ret = hgcm_call_preprocess(parms, parm_count, &bounce_bufs, &size);
+	if (ret) {
+		/* Even on error bounce bufs may still have been allocated */
+		goto free_bounce_bufs;
+	}
+
+	call = vbg_req_alloc(size, VMMDEVREQ_HGCM_CALL, requestor);
+	if (!call) {
+		ret = -ENOMEM;
+		goto free_bounce_bufs;
+	}
+
+	hgcm_call_init_call(call, client_id, function, parms, parm_count,
+			    bounce_bufs);
+
+	ret = vbg_hgcm_do_call(gdev, call, timeout_ms,
+			       requestor & VMMDEV_REQUESTOR_USERMODE, &leak_it);
+	if (ret == 0) {
+		*vbox_status = call->header.result;
+		ret = hgcm_call_copy_back_result(call, parms, parm_count,
+						 bounce_bufs);
+	}
+
+	if (!leak_it)
+		vbg_req_free(call, size);
+
+free_bounce_bufs:
+	if (bounce_bufs) {
+		for (i = 0; i < parm_count; i++)
+			kvfree(bounce_bufs[i]);
+		kfree(bounce_bufs);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(vbg_hgcm_call);
+
+#ifdef CONFIG_COMPAT
+int vbg_hgcm_call32(
+	struct vbg_dev *gdev, u32 requestor, u32 client_id, u32 function,
+	u32 timeout_ms, struct vmmdev_hgcm_function_parameter32 *parm32,
+	u32 parm_count, int *vbox_status)
+{
+	struct vmmdev_hgcm_function_parameter *parm64 = NULL;
+	u32 i, size;
+	int ret = 0;
+
+	/* KISS allocate a temporary request and convert the parameters. */
+	size = parm_count * sizeof(struct vmmdev_hgcm_function_parameter);
+	parm64 = kzalloc(size, GFP_KERNEL);
+	if (!parm64)
+		return -ENOMEM;
+
+	for (i = 0; i < parm_count; i++) {
+		switch (parm32[i].type) {
+		case VMMDEV_HGCM_PARM_TYPE_32BIT:
+			parm64[i].type = VMMDEV_HGCM_PARM_TYPE_32BIT;
+			parm64[i].u.value32 = parm32[i].u.value32;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_64BIT:
+			parm64[i].type = VMMDEV_HGCM_PARM_TYPE_64BIT;
+			parm64[i].u.value64 = parm32[i].u.value64;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+			parm64[i].type = parm32[i].type;
+			parm64[i].u.pointer.size = parm32[i].u.pointer.size;
+			parm64[i].u.pointer.u.linear_addr =
+			    parm32[i].u.pointer.u.linear_addr;
+			break;
+
+		default:
+			ret = -EINVAL;
+		}
+		if (ret < 0)
+			goto out_free;
+	}
+
+	ret = vbg_hgcm_call(gdev, requestor, client_id, function, timeout_ms,
+			    parm64, parm_count, vbox_status);
+	if (ret < 0)
+		goto out_free;
+
+	/* Copy back. */
+	for (i = 0; i < parm_count; i++, parm32++, parm64++) {
+		switch (parm64[i].type) {
+		case VMMDEV_HGCM_PARM_TYPE_32BIT:
+			parm32[i].u.value32 = parm64[i].u.value32;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_64BIT:
+			parm32[i].u.value64 = parm64[i].u.value64;
+			break;
+
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
+		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
+			parm32[i].u.pointer.size = parm64[i].u.pointer.size;
+			break;
+
+		default:
+			WARN_ON(1);
+			ret = -EINVAL;
+		}
+	}
+
+out_free:
+	kfree(parm64);
+	return ret;
+}
+#endif
+
+static const int vbg_status_code_to_errno_table[] = {
+	[-VERR_ACCESS_DENIED]                            = -EPERM,
+	[-VERR_FILE_NOT_FOUND]                           = -ENOENT,
+	[-VERR_PROCESS_NOT_FOUND]                        = -ESRCH,
+	[-VERR_INTERRUPTED]                              = -EINTR,
+	[-VERR_DEV_IO_ERROR]                             = -EIO,
+	[-VERR_TOO_MUCH_DATA]                            = -E2BIG,
+	[-VERR_BAD_EXE_FORMAT]                           = -ENOEXEC,
+	[-VERR_INVALID_HANDLE]                           = -EBADF,
+	[-VERR_TRY_AGAIN]                                = -EAGAIN,
+	[-VERR_NO_MEMORY]                                = -ENOMEM,
+	[-VERR_INVALID_POINTER]                          = -EFAULT,
+	[-VERR_RESOURCE_BUSY]                            = -EBUSY,
+	[-VERR_ALREADY_EXISTS]                           = -EEXIST,
+	[-VERR_NOT_SAME_DEVICE]                          = -EXDEV,
+	[-VERR_NOT_A_DIRECTORY]                          = -ENOTDIR,
+	[-VERR_PATH_NOT_FOUND]                           = -ENOTDIR,
+	[-VERR_INVALID_NAME]                             = -ENOENT,
+	[-VERR_IS_A_DIRECTORY]                           = -EISDIR,
+	[-VERR_INVALID_PARAMETER]                        = -EINVAL,
+	[-VERR_TOO_MANY_OPEN_FILES]                      = -ENFILE,
+	[-VERR_INVALID_FUNCTION]                         = -ENOTTY,
+	[-VERR_SHARING_VIOLATION]                        = -ETXTBSY,
+	[-VERR_FILE_TOO_BIG]                             = -EFBIG,
+	[-VERR_DISK_FULL]                                = -ENOSPC,
+	[-VERR_SEEK_ON_DEVICE]                           = -ESPIPE,
+	[-VERR_WRITE_PROTECT]                            = -EROFS,
+	[-VERR_BROKEN_PIPE]                              = -EPIPE,
+	[-VERR_DEADLOCK]                                 = -EDEADLK,
+	[-VERR_FILENAME_TOO_LONG]                        = -ENAMETOOLONG,
+	[-VERR_FILE_LOCK_FAILED]                         = -ENOLCK,
+	[-VERR_NOT_IMPLEMENTED]                          = -ENOSYS,
+	[-VERR_NOT_SUPPORTED]                            = -ENOSYS,
+	[-VERR_DIR_NOT_EMPTY]                            = -ENOTEMPTY,
+	[-VERR_TOO_MANY_SYMLINKS]                        = -ELOOP,
+	[-VERR_NO_MORE_FILES]				 = -ENODATA,
+	[-VERR_NO_DATA]                                  = -ENODATA,
+	[-VERR_NET_NO_NETWORK]                           = -ENONET,
+	[-VERR_NET_NOT_UNIQUE_NAME]                      = -ENOTUNIQ,
+	[-VERR_NO_TRANSLATION]                           = -EILSEQ,
+	[-VERR_NET_NOT_SOCKET]                           = -ENOTSOCK,
+	[-VERR_NET_DEST_ADDRESS_REQUIRED]                = -EDESTADDRREQ,
+	[-VERR_NET_MSG_SIZE]                             = -EMSGSIZE,
+	[-VERR_NET_PROTOCOL_TYPE]                        = -EPROTOTYPE,
+	[-VERR_NET_PROTOCOL_NOT_AVAILABLE]               = -ENOPROTOOPT,
+	[-VERR_NET_PROTOCOL_NOT_SUPPORTED]               = -EPROTONOSUPPORT,
+	[-VERR_NET_SOCKET_TYPE_NOT_SUPPORTED]            = -ESOCKTNOSUPPORT,
+	[-VERR_NET_OPERATION_NOT_SUPPORTED]              = -EOPNOTSUPP,
+	[-VERR_NET_PROTOCOL_FAMILY_NOT_SUPPORTED]        = -EPFNOSUPPORT,
+	[-VERR_NET_ADDRESS_FAMILY_NOT_SUPPORTED]         = -EAFNOSUPPORT,
+	[-VERR_NET_ADDRESS_IN_USE]                       = -EADDRINUSE,
+	[-VERR_NET_ADDRESS_NOT_AVAILABLE]                = -EADDRNOTAVAIL,
+	[-VERR_NET_DOWN]                                 = -ENETDOWN,
+	[-VERR_NET_UNREACHABLE]                          = -ENETUNREACH,
+	[-VERR_NET_CONNECTION_RESET]                     = -ENETRESET,
+	[-VERR_NET_CONNECTION_ABORTED]                   = -ECONNABORTED,
+	[-VERR_NET_CONNECTION_RESET_BY_PEER]             = -ECONNRESET,
+	[-VERR_NET_NO_BUFFER_SPACE]                      = -ENOBUFS,
+	[-VERR_NET_ALREADY_CONNECTED]                    = -EISCONN,
+	[-VERR_NET_NOT_CONNECTED]                        = -ENOTCONN,
+	[-VERR_NET_SHUTDOWN]                             = -ESHUTDOWN,
+	[-VERR_NET_TOO_MANY_REFERENCES]                  = -ETOOMANYREFS,
+	[-VERR_TIMEOUT]                                  = -ETIMEDOUT,
+	[-VERR_NET_CONNECTION_REFUSED]                   = -ECONNREFUSED,
+	[-VERR_NET_HOST_DOWN]                            = -EHOSTDOWN,
+	[-VERR_NET_HOST_UNREACHABLE]                     = -EHOSTUNREACH,
+	[-VERR_NET_ALREADY_IN_PROGRESS]                  = -EALREADY,
+	[-VERR_NET_IN_PROGRESS]                          = -EINPROGRESS,
+	[-VERR_MEDIA_NOT_PRESENT]                        = -ENOMEDIUM,
+	[-VERR_MEDIA_NOT_RECOGNIZED]                     = -EMEDIUMTYPE,
+};
+
+int vbg_status_code_to_errno(int rc)
+{
+	if (rc >= 0)
+		return 0;
+
+	rc = -rc;
+	if (rc >= ARRAY_SIZE(vbg_status_code_to_errno_table) ||
+	    vbg_status_code_to_errno_table[rc] == 0) {
+		vbg_warn("%s: Unhandled err %d\n", __func__, -rc);
+		return -EPROTO;
+	}
+
+	return vbg_status_code_to_errno_table[rc];
+}
+EXPORT_SYMBOL(vbg_status_code_to_errno);
diff --git a/drivers/virt/vboxguest/vboxguest_version.h b/drivers/virt/vboxguest/vboxguest_version.h
new file mode 100644
index 000000000..84834dad3
--- /dev/null
+++ b/drivers/virt/vboxguest/vboxguest_version.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
+/*
+ * VBox Guest additions version info, this is used by the host to determine
+ * supported guest-addition features in some cases. So this will need to be
+ * synced with vbox upstreams versioning scheme when we implement / port
+ * new features from the upstream out-of-tree vboxguest driver.
+ */
+
+#ifndef __VBOX_VERSION_H__
+#define __VBOX_VERSION_H__
+
+#define VBG_VERSION_MAJOR 6
+#define VBG_VERSION_MINOR 0
+#define VBG_VERSION_BUILD 0
+#define VBG_SVN_REV 127566
+#define VBG_VERSION_STRING "6.0.0"
+
+#endif
diff --git a/drivers/virt/vboxguest/vmmdev.h b/drivers/virt/vboxguest/vmmdev.h
new file mode 100644
index 000000000..21f408120
--- /dev/null
+++ b/drivers/virt/vboxguest/vmmdev.h
@@ -0,0 +1,453 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
+/*
+ * Virtual Device for Guest <-> VMM/Host communication interface
+ *
+ * Copyright (C) 2006-2016 Oracle Corporation
+ */
+
+#ifndef __VBOX_VMMDEV_H__
+#define __VBOX_VMMDEV_H__
+
+#include <asm/bitsperlong.h>
+#include <linux/sizes.h>
+#include <linux/types.h>
+#include <linux/vbox_vmmdev_types.h>
+
+/* Port for generic request interface (relative offset). */
+#define VMMDEV_PORT_OFF_REQUEST                             0
+
+/** Layout of VMMDEV RAM region that contains information for guest. */
+struct vmmdev_memory {
+	/** The size of this structure. */
+	u32 size;
+	/** The structure version. (VMMDEV_MEMORY_VERSION) */
+	u32 version;
+
+	union {
+		struct {
+			/** Flag telling that VMMDev has events pending. */
+			u8 have_events;
+			/** Explicit padding, MBZ. */
+			u8 padding[3];
+		} V1_04;
+
+		struct {
+			/** Pending events flags, set by host. */
+			u32 host_events;
+			/** Mask of events the guest wants, set by guest. */
+			u32 guest_event_mask;
+		} V1_03;
+	} V;
+
+	/* struct vbva_memory, not used */
+};
+VMMDEV_ASSERT_SIZE(vmmdev_memory, 8 + 8);
+
+/** Version of vmmdev_memory structure (vmmdev_memory::version). */
+#define VMMDEV_MEMORY_VERSION   (1)
+
+/* Host mouse capabilities has been changed. */
+#define VMMDEV_EVENT_MOUSE_CAPABILITIES_CHANGED             BIT(0)
+/* HGCM event. */
+#define VMMDEV_EVENT_HGCM                                   BIT(1)
+/* A display change request has been issued. */
+#define VMMDEV_EVENT_DISPLAY_CHANGE_REQUEST                 BIT(2)
+/* Credentials are available for judgement. */
+#define VMMDEV_EVENT_JUDGE_CREDENTIALS                      BIT(3)
+/* The guest has been restored. */
+#define VMMDEV_EVENT_RESTORED                               BIT(4)
+/* Seamless mode state changed. */
+#define VMMDEV_EVENT_SEAMLESS_MODE_CHANGE_REQUEST           BIT(5)
+/* Memory balloon size changed. */
+#define VMMDEV_EVENT_BALLOON_CHANGE_REQUEST                 BIT(6)
+/* Statistics interval changed. */
+#define VMMDEV_EVENT_STATISTICS_INTERVAL_CHANGE_REQUEST     BIT(7)
+/* VRDP status changed. */
+#define VMMDEV_EVENT_VRDP                                   BIT(8)
+/* New mouse position data available. */
+#define VMMDEV_EVENT_MOUSE_POSITION_CHANGED                 BIT(9)
+/* CPU hotplug event occurred. */
+#define VMMDEV_EVENT_CPU_HOTPLUG                            BIT(10)
+/* The mask of valid events, for sanity checking. */
+#define VMMDEV_EVENT_VALID_EVENT_MASK                       0x000007ffU
+
+/*
+ * Additions are allowed to work only if additions_major == vmmdev_current &&
+ * additions_minor <= vmmdev_current. Additions version is reported to host
+ * (VMMDev) by VMMDEVREQ_REPORT_GUEST_INFO.
+ */
+#define VMMDEV_VERSION                      0x00010004
+#define VMMDEV_VERSION_MAJOR                (VMMDEV_VERSION >> 16)
+#define VMMDEV_VERSION_MINOR                (VMMDEV_VERSION & 0xffff)
+
+/* Maximum request packet size. */
+#define VMMDEV_MAX_VMMDEVREQ_SIZE           1048576
+
+/* Version of vmmdev_request_header structure. */
+#define VMMDEV_REQUEST_HEADER_VERSION       0x10001
+
+/** struct vmmdev_request_header - Generic VMMDev request header. */
+struct vmmdev_request_header {
+	/** IN: Size of the structure in bytes (including body). */
+	u32 size;
+	/** IN: Version of the structure.  */
+	u32 version;
+	/** IN: Type of the request. */
+	enum vmmdev_request_type request_type;
+	/** OUT: Return code. */
+	s32 rc;
+	/** Reserved field no.1. MBZ. */
+	u32 reserved1;
+	/** IN: Requestor information (VMMDEV_REQUESTOR_*) */
+	u32 requestor;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_request_header, 24);
+
+/**
+ * struct vmmdev_mouse_status - Mouse status request structure.
+ *
+ * Used by VMMDEVREQ_GET_MOUSE_STATUS and VMMDEVREQ_SET_MOUSE_STATUS.
+ */
+struct vmmdev_mouse_status {
+	/** header */
+	struct vmmdev_request_header header;
+	/** Mouse feature mask. See VMMDEV_MOUSE_*. */
+	u32 mouse_features;
+	/** Mouse x position. */
+	s32 pointer_pos_x;
+	/** Mouse y position. */
+	s32 pointer_pos_y;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_mouse_status, 24 + 12);
+
+/* The guest can (== wants to) handle absolute coordinates.  */
+#define VMMDEV_MOUSE_GUEST_CAN_ABSOLUTE                     BIT(0)
+/*
+ * The host can (== wants to) send absolute coordinates.
+ * (Input not captured.)
+ */
+#define VMMDEV_MOUSE_HOST_WANTS_ABSOLUTE                    BIT(1)
+/*
+ * The guest can *NOT* switch to software cursor and therefore depends on the
+ * host cursor.
+ *
+ * When guest additions are installed and the host has promised to display the
+ * cursor itself, the guest installs a hardware mouse driver. Don't ask the
+ * guest to switch to a software cursor then.
+ */
+#define VMMDEV_MOUSE_GUEST_NEEDS_HOST_CURSOR                BIT(2)
+/* The host does NOT provide support for drawing the cursor itself. */
+#define VMMDEV_MOUSE_HOST_CANNOT_HWPOINTER                  BIT(3)
+/* The guest can read VMMDev events to find out about pointer movement */
+#define VMMDEV_MOUSE_NEW_PROTOCOL                           BIT(4)
+/*
+ * If the guest changes the status of the VMMDEV_MOUSE_GUEST_NEEDS_HOST_CURSOR
+ * bit, the host will honour this.
+ */
+#define VMMDEV_MOUSE_HOST_RECHECKS_NEEDS_HOST_CURSOR        BIT(5)
+/*
+ * The host supplies an absolute pointing device.  The Guest Additions may
+ * wish to use this to decide whether to install their own driver.
+ */
+#define VMMDEV_MOUSE_HOST_HAS_ABS_DEV                       BIT(6)
+
+/* The minimum value our pointing device can return. */
+#define VMMDEV_MOUSE_RANGE_MIN 0
+/* The maximum value our pointing device can return. */
+#define VMMDEV_MOUSE_RANGE_MAX 0xFFFF
+
+/**
+ * struct vmmdev_host_version - VirtualBox host version request structure.
+ *
+ * VBG uses this to detect the precense of new features in the interface.
+ */
+struct vmmdev_host_version {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Major version. */
+	u16 major;
+	/** Minor version. */
+	u16 minor;
+	/** Build number. */
+	u32 build;
+	/** SVN revision. */
+	u32 revision;
+	/** Feature mask. */
+	u32 features;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_host_version, 24 + 16);
+
+/* Physical page lists are supported by HGCM. */
+#define VMMDEV_HVF_HGCM_PHYS_PAGE_LIST  BIT(0)
+
+/**
+ * struct vmmdev_mask - Structure to set / clear bits in a mask used for
+ * VMMDEVREQ_SET_GUEST_CAPABILITIES and VMMDEVREQ_CTL_GUEST_FILTER_MASK.
+ */
+struct vmmdev_mask {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Mask of bits to be set. */
+	u32 or_mask;
+	/** Mask of bits to be cleared. */
+	u32 not_mask;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_mask, 24 + 8);
+
+/* The guest supports seamless display rendering. */
+#define VMMDEV_GUEST_SUPPORTS_SEAMLESS                      BIT(0)
+/* The guest supports mapping guest to host windows. */
+#define VMMDEV_GUEST_SUPPORTS_GUEST_HOST_WINDOW_MAPPING     BIT(1)
+/*
+ * The guest graphical additions are active.
+ * Used for fast activation and deactivation of certain graphical operations
+ * (e.g. resizing & seamless). The legacy VMMDEVREQ_REPORT_GUEST_CAPABILITIES
+ * request sets this automatically, but VMMDEVREQ_SET_GUEST_CAPABILITIES does
+ * not.
+ */
+#define VMMDEV_GUEST_SUPPORTS_GRAPHICS                      BIT(2)
+/* The mask of valid capabilities, for sanity checking. */
+#define VMMDEV_GUEST_CAPABILITIES_MASK                      0x00000007U
+
+/** struct vmmdev_hypervisorinfo - Hypervisor info structure. */
+struct vmmdev_hypervisorinfo {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/**
+	 * Guest virtual address of proposed hypervisor start.
+	 * Not used by VMMDEVREQ_GET_HYPERVISOR_INFO.
+	 */
+	u32 hypervisor_start;
+	/** Hypervisor size in bytes. */
+	u32 hypervisor_size;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hypervisorinfo, 24 + 8);
+
+/** struct vmmdev_events - Pending events structure. */
+struct vmmdev_events {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** OUT: Pending event mask. */
+	u32 events;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_events, 24 + 4);
+
+#define VMMDEV_OSTYPE_LINUX26		0x53000
+#define VMMDEV_OSTYPE_X64		BIT(8)
+
+/** struct vmmdev_guestinfo - Guest information report. */
+struct vmmdev_guest_info {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/**
+	 * The VMMDev interface version expected by additions.
+	 * *Deprecated*, do not use anymore! Will be removed.
+	 */
+	u32 interface_version;
+	/** Guest OS type. */
+	u32 os_type;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_guest_info, 24 + 8);
+
+#define VMMDEV_GUEST_INFO2_ADDITIONS_FEATURES_REQUESTOR_INFO	BIT(0)
+
+/** struct vmmdev_guestinfo2 - Guest information report, version 2. */
+struct vmmdev_guest_info2 {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Major version. */
+	u16 additions_major;
+	/** Minor version. */
+	u16 additions_minor;
+	/** Build number. */
+	u32 additions_build;
+	/** SVN revision. */
+	u32 additions_revision;
+	/** Feature mask. */
+	u32 additions_features;
+	/**
+	 * The intentional meaning of this field was:
+	 * Some additional information, for example 'Beta 1' or something like
+	 * that.
+	 *
+	 * The way it was implemented was implemented: VBG_VERSION_STRING.
+	 *
+	 * This means the first three members are duplicated in this field (if
+	 * the guest build config is sane). So, the user must check this and
+	 * chop it off before usage. There is, because of the Main code's blind
+	 * trust in the field's content, no way back.
+	 */
+	char name[128];
+};
+VMMDEV_ASSERT_SIZE(vmmdev_guest_info2, 24 + 144);
+
+enum vmmdev_guest_facility_type {
+	VBOXGUEST_FACILITY_TYPE_UNKNOWN          = 0,
+	VBOXGUEST_FACILITY_TYPE_VBOXGUEST_DRIVER = 20,
+	/* VBoxGINA / VBoxCredProv / pam_vbox. */
+	VBOXGUEST_FACILITY_TYPE_AUTO_LOGON       = 90,
+	VBOXGUEST_FACILITY_TYPE_VBOX_SERVICE     = 100,
+	/* VBoxTray (Windows), VBoxClient (Linux, Unix). */
+	VBOXGUEST_FACILITY_TYPE_VBOX_TRAY_CLIENT = 101,
+	VBOXGUEST_FACILITY_TYPE_SEAMLESS         = 1000,
+	VBOXGUEST_FACILITY_TYPE_GRAPHICS         = 1100,
+	VBOXGUEST_FACILITY_TYPE_ALL              = 0x7ffffffe,
+	/* Ensure the enum is a 32 bit data-type */
+	VBOXGUEST_FACILITY_TYPE_SIZEHACK         = 0x7fffffff
+};
+
+enum vmmdev_guest_facility_status {
+	VBOXGUEST_FACILITY_STATUS_INACTIVE    = 0,
+	VBOXGUEST_FACILITY_STATUS_PAUSED      = 1,
+	VBOXGUEST_FACILITY_STATUS_PRE_INIT    = 20,
+	VBOXGUEST_FACILITY_STATUS_INIT        = 30,
+	VBOXGUEST_FACILITY_STATUS_ACTIVE      = 50,
+	VBOXGUEST_FACILITY_STATUS_TERMINATING = 100,
+	VBOXGUEST_FACILITY_STATUS_TERMINATED  = 101,
+	VBOXGUEST_FACILITY_STATUS_FAILED      = 800,
+	VBOXGUEST_FACILITY_STATUS_UNKNOWN     = 999,
+	/* Ensure the enum is a 32 bit data-type */
+	VBOXGUEST_FACILITY_STATUS_SIZEHACK    = 0x7fffffff
+};
+
+/** struct vmmdev_guest_status - Guest Additions status structure. */
+struct vmmdev_guest_status {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Facility the status is indicated for. */
+	enum vmmdev_guest_facility_type facility;
+	/** Current guest status. */
+	enum vmmdev_guest_facility_status status;
+	/** Flags, not used at the moment. */
+	u32 flags;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_guest_status, 24 + 12);
+
+#define VMMDEV_MEMORY_BALLOON_CHUNK_SIZE             (1048576)
+#define VMMDEV_MEMORY_BALLOON_CHUNK_PAGES            (1048576 / 4096)
+
+/** struct vmmdev_memballoon_info - Memory-balloon info structure. */
+struct vmmdev_memballoon_info {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Balloon size in megabytes. */
+	u32 balloon_chunks;
+	/** Guest ram size in megabytes. */
+	u32 phys_mem_chunks;
+	/**
+	 * Setting this to VMMDEV_EVENT_BALLOON_CHANGE_REQUEST indicates that
+	 * the request is a response to that event.
+	 * (Don't confuse this with VMMDEVREQ_ACKNOWLEDGE_EVENTS.)
+	 */
+	u32 event_ack;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_memballoon_info, 24 + 12);
+
+/** struct vmmdev_memballoon_change - Change the size of the balloon. */
+struct vmmdev_memballoon_change {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** The number of pages in the array. */
+	u32 pages;
+	/** true = inflate, false = deflate.  */
+	u32 inflate;
+	/** Physical address (u64) of each page. */
+	u64 phys_page[VMMDEV_MEMORY_BALLOON_CHUNK_PAGES];
+};
+
+/** struct vmmdev_write_core_dump - Write Core Dump request data. */
+struct vmmdev_write_core_dump {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** Flags (reserved, MBZ). */
+	u32 flags;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_write_core_dump, 24 + 4);
+
+/** struct vmmdev_heartbeat - Heart beat check state structure. */
+struct vmmdev_heartbeat {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** OUT: Guest heartbeat interval in nanosec. */
+	u64 interval_ns;
+	/** Heartbeat check flag. */
+	u8 enabled;
+	/** Explicit padding, MBZ. */
+	u8 padding[3];
+} __packed;
+VMMDEV_ASSERT_SIZE(vmmdev_heartbeat, 24 + 12);
+
+#define VMMDEV_HGCM_REQ_DONE      BIT(0)
+#define VMMDEV_HGCM_REQ_CANCELLED BIT(1)
+
+/** struct vmmdev_hgcmreq_header - vmmdev HGCM requests header. */
+struct vmmdev_hgcmreq_header {
+	/** Request header. */
+	struct vmmdev_request_header header;
+
+	/** HGCM flags. */
+	u32 flags;
+
+	/** Result code. */
+	s32 result;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hgcmreq_header, 24 + 8);
+
+/** struct vmmdev_hgcm_connect - HGCM connect request structure. */
+struct vmmdev_hgcm_connect {
+	/** HGCM request header. */
+	struct vmmdev_hgcmreq_header header;
+
+	/** IN: Description of service to connect to. */
+	struct vmmdev_hgcm_service_location loc;
+
+	/** OUT: Client identifier assigned by local instance of HGCM. */
+	u32 client_id;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hgcm_connect, 32 + 132 + 4);
+
+/** struct vmmdev_hgcm_disconnect - HGCM disconnect request structure. */
+struct vmmdev_hgcm_disconnect {
+	/** HGCM request header. */
+	struct vmmdev_hgcmreq_header header;
+
+	/** IN: Client identifier. */
+	u32 client_id;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hgcm_disconnect, 32 + 4);
+
+#define VMMDEV_HGCM_MAX_PARMS 32
+
+/** struct vmmdev_hgcm_call - HGCM call request structure. */
+struct vmmdev_hgcm_call {
+	/* request header */
+	struct vmmdev_hgcmreq_header header;
+
+	/** IN: Client identifier. */
+	u32 client_id;
+	/** IN: Service function number. */
+	u32 function;
+	/** IN: Number of parameters. */
+	u32 parm_count;
+	/** Parameters follow in form: HGCMFunctionParameter32|64 parms[X]; */
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hgcm_call, 32 + 12);
+
+/**
+ * struct vmmdev_hgcm_cancel2 - HGCM cancel request structure, version 2.
+ *
+ * After the request header.rc will be:
+ *
+ * VINF_SUCCESS when cancelled.
+ * VERR_NOT_FOUND if the specified request cannot be found.
+ * VERR_INVALID_PARAMETER if the address is invalid valid.
+ */
+struct vmmdev_hgcm_cancel2 {
+	/** Header. */
+	struct vmmdev_request_header header;
+	/** The physical address of the request to cancel. */
+	u32 phys_req_to_cancel;
+};
+VMMDEV_ASSERT_SIZE(vmmdev_hgcm_cancel2, 24 + 4);
+
+#endif