[RESEND,v9,2/4] uacce: add uacce driver

diff --git a/Documentation/ABI/testing/sysfs-driver-uacce b/Documentation/ABI/testing/sysfs-driver-uacce
new file mode 100644
index 0000000..8520d68
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-uacce
@@ -0,0 +1,37 @@ 
+What:           /sys/class/uacce/<dev_name>/api
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Api of the device, no requirement of the format
+                Application use the api to match the correct driver
+
+What:           /sys/class/uacce/<dev_name>/flags
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Attributes of the device, see UACCE_DEV_xxx flag defined in uacce.h
+
+What:           /sys/class/uacce/<dev_name>/available_instances
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Available instances left of the device
+                Return -ENODEV if uacce_ops get_available_instances is not provided
+
+What:           /sys/class/uacce/<dev_name>/algorithms
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Algorithms supported by this accelerator, separated by new line.
+
+What:           /sys/class/uacce/<dev_name>/region_mmio_size
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Size (bytes) of mmio region queue file
+
+What:           /sys/class/uacce/<dev_name>/region_dus_size
+Date:           Dec 2019
+KernelVersion:  5.6
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Size (bytes) of dus region queue file
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 7f0d48f..99e1514 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -480,4 +480,5 @@  source "drivers/misc/cxl/Kconfig"
 source "drivers/misc/ocxl/Kconfig"
 source "drivers/misc/cardreader/Kconfig"
 source "drivers/misc/habanalabs/Kconfig"
+source "drivers/misc/uacce/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index c1860d3..9abf292 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -56,4 +56,5 @@  obj-$(CONFIG_OCXL)		+= ocxl/
 obj-y				+= cardreader/
 obj-$(CONFIG_PVPANIC)   	+= pvpanic.o
 obj-$(CONFIG_HABANA_AI)		+= habanalabs/
+obj-$(CONFIG_UACCE)		+= uacce/
 obj-$(CONFIG_XILINX_SDFEC)	+= xilinx_sdfec.o
diff --git a/drivers/misc/uacce/Kconfig b/drivers/misc/uacce/Kconfig
new file mode 100644
index 0000000..5e39b60
--- /dev/null
+++ b/drivers/misc/uacce/Kconfig
@@ -0,0 +1,13 @@ 
+config UACCE
+	tristate "Accelerator Framework for User Land"
+	depends on IOMMU_API
+	help
+	  UACCE provides interface for the user process to access the hardware
+	  without interaction with the kernel space in data path.
+
+	  The user-space interface is described in
+	  include/uapi/misc/uacce/uacce.h
+
+	  See Documentation/misc-devices/uacce.rst for more details.
+
+	  If you don't know what to do here, say N.
diff --git a/drivers/misc/uacce/Makefile b/drivers/misc/uacce/Makefile
new file mode 100644
index 0000000..5b4374e
--- /dev/null
+++ b/drivers/misc/uacce/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0-or-later
+obj-$(CONFIG_UACCE) += uacce.o
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
new file mode 100644
index 0000000..d7452b1
--- /dev/null
+++ b/drivers/misc/uacce/uacce.c
@@ -0,0 +1,627 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/compat.h>
+#include <linux/dma-iommu.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/uacce.h>
+
+static struct class *uacce_class;
+static dev_t uacce_devt;
+static DEFINE_MUTEX(uacce_mutex);
+static DEFINE_XARRAY_ALLOC(uacce_xa);
+
+static int uacce_start_queue(struct uacce_queue *q)
+{
+	int ret = 0;
+
+	mutex_lock(&uacce_mutex);
+
+	if (q->state != UACCE_Q_INIT) {
+		ret = -EINVAL;
+		goto out_with_lock;
+	}
+
+	if (q->uacce->ops->start_queue) {
+		ret = q->uacce->ops->start_queue(q);
+		if (ret < 0)
+			goto out_with_lock;
+	}
+
+	q->state = UACCE_Q_STARTED;
+
+out_with_lock:
+	mutex_unlock(&uacce_mutex);
+
+	return ret;
+}
+
+static int uacce_put_queue(struct uacce_queue *q)
+{
+	struct uacce_device *uacce = q->uacce;
+
+	mutex_lock(&uacce_mutex);
+
+	if (q->state == UACCE_Q_ZOMBIE)
+		goto out;
+
+	if ((q->state == UACCE_Q_STARTED) && uacce->ops->stop_queue)
+		uacce->ops->stop_queue(q);
+
+	if ((q->state == UACCE_Q_INIT || q->state == UACCE_Q_STARTED) &&
+	     uacce->ops->put_queue)
+		uacce->ops->put_queue(q);
+
+	q->state = UACCE_Q_ZOMBIE;
+out:
+	mutex_unlock(&uacce_mutex);
+
+	return 0;
+}
+
+static long uacce_fops_unl_ioctl(struct file *filep,
+				 unsigned int cmd, unsigned long arg)
+{
+	struct uacce_queue *q = filep->private_data;
+	struct uacce_device *uacce = q->uacce;
+
+	switch (cmd) {
+	case UACCE_CMD_START_Q:
+		return uacce_start_queue(q);
+
+	case UACCE_CMD_PUT_Q:
+		return uacce_put_queue(q);
+
+	default:
+		if (!uacce->ops->ioctl)
+			return -EINVAL;
+
+		return uacce->ops->ioctl(q, cmd, arg);
+	}
+}
+
+#ifdef CONFIG_COMPAT
+static long uacce_fops_compat_ioctl(struct file *filep,
+				   unsigned int cmd, unsigned long arg)
+{
+	arg = (unsigned long)compat_ptr(arg);
+
+	return uacce_fops_unl_ioctl(filep, cmd, arg);
+}
+#endif
+
+static int uacce_sva_exit(struct device *dev, struct iommu_sva *handle,
+			  void *data)
+{
+	struct uacce_mm *uacce_mm = data;
+	struct uacce_queue *q;
+
+	/*
+	 * No new queue can be added concurrently because no caller can have a
+	 * reference to this mm. But there may be concurrent calls to
+	 * uacce_mm_put(), so we need the lock.
+	 */
+	mutex_lock(&uacce_mm->lock);
+	list_for_each_entry(q, &uacce_mm->queues, list)
+		uacce_put_queue(q);
+	uacce_mm->mm = NULL;
+	mutex_unlock(&uacce_mm->lock);
+
+	return 0;
+}
+
+static struct iommu_sva_ops uacce_sva_ops = {
+	.mm_exit = uacce_sva_exit,
+};
+
+static struct uacce_mm *uacce_mm_get(struct uacce_device *uacce,
+				     struct uacce_queue *q,
+				     struct mm_struct *mm)
+{
+	struct uacce_mm *uacce_mm = NULL;
+	struct iommu_sva *handle = NULL;
+	int ret;
+
+	lockdep_assert_held(&uacce->mm_lock);
+
+	list_for_each_entry(uacce_mm, &uacce->mm_list, list) {
+		if (uacce_mm->mm == mm) {
+			mutex_lock(&uacce_mm->lock);
+			list_add(&q->list, &uacce_mm->queues);
+			mutex_unlock(&uacce_mm->lock);
+			return uacce_mm;
+		}
+	}
+
+	uacce_mm = kzalloc(sizeof(*uacce_mm), GFP_KERNEL);
+	if (!uacce_mm)
+		return NULL;
+
+	if (uacce->flags & UACCE_DEV_SVA) {
+		/*
+		 * Safe to pass an incomplete uacce_mm, since mm_exit cannot
+		 * fire while we hold a reference to the mm.
+		 */
+		handle = iommu_sva_bind_device(uacce->parent, mm, uacce_mm);
+		if (IS_ERR(handle))
+			goto err_free;
+
+		ret = iommu_sva_set_ops(handle, &uacce_sva_ops);
+		if (ret)
+			goto err_unbind;
+
+		uacce_mm->pasid = iommu_sva_get_pasid(handle);
+		if (uacce_mm->pasid == IOMMU_PASID_INVALID)
+			goto err_unbind;
+	}
+
+	uacce_mm->mm = mm;
+	uacce_mm->handle = handle;
+	INIT_LIST_HEAD(&uacce_mm->queues);
+	mutex_init(&uacce_mm->lock);
+	list_add(&q->list, &uacce_mm->queues);
+	list_add(&uacce_mm->list, &uacce->mm_list);
+
+	return uacce_mm;
+
+err_unbind:
+	if (handle)
+		iommu_sva_unbind_device(handle);
+err_free:
+	kfree(uacce_mm);
+	return NULL;
+}
+
+static void uacce_mm_put(struct uacce_queue *q)
+{
+	struct uacce_mm *uacce_mm = q->uacce_mm;
+
+	lockdep_assert_held(&q->uacce->mm_lock);
+
+	mutex_lock(&uacce_mm->lock);
+	list_del(&q->list);
+	mutex_unlock(&uacce_mm->lock);
+
+	if (list_empty(&uacce_mm->queues)) {
+		if (uacce_mm->handle)
+			iommu_sva_unbind_device(uacce_mm->handle);
+		list_del(&uacce_mm->list);
+		kfree(uacce_mm);
+	}
+}
+
+static int uacce_fops_open(struct inode *inode, struct file *filep)
+{
+	struct uacce_mm *uacce_mm = NULL;
+	struct uacce_device *uacce;
+	struct uacce_queue *q;
+	int ret = 0;
+
+	uacce = xa_load(&uacce_xa, iminor(inode));
+	if (!uacce)
+		return -ENODEV;
+
+	if (!try_module_get(uacce->parent->driver->owner))
+		return -ENODEV;
+
+	q = kzalloc(sizeof(struct uacce_queue), GFP_KERNEL);
+	if (!q) {
+		ret = -ENOMEM;
+		goto out_with_module;
+	}
+
+	mutex_lock(&uacce->mm_lock);
+	uacce_mm = uacce_mm_get(uacce, q, current->mm);
+	mutex_unlock(&uacce->mm_lock);
+	if (!uacce_mm) {
+		ret = -ENOMEM;
+		goto out_with_mem;
+	}
+
+	q->uacce = uacce;
+	q->uacce_mm = uacce_mm;
+
+	if (uacce->ops->get_queue) {
+		ret = uacce->ops->get_queue(uacce, uacce_mm->pasid, q);
+		if (ret < 0)
+			goto out_with_mm;
+	}
+
+	init_waitqueue_head(&q->wait);
+	filep->private_data = q;
+	q->state = UACCE_Q_INIT;
+
+	return 0;
+
+out_with_mm:
+	mutex_lock(&uacce->mm_lock);
+	uacce_mm_put(q);
+	mutex_unlock(&uacce->mm_lock);
+out_with_mem:
+	kfree(q);
+out_with_module:
+	module_put(uacce->parent->driver->owner);
+	return ret;
+}
+
+static int uacce_fops_release(struct inode *inode, struct file *filep)
+{
+	struct uacce_queue *q = filep->private_data;
+	struct uacce_device *uacce = q->uacce;
+
+	uacce_put_queue(q);
+
+	mutex_lock(&uacce->mm_lock);
+	uacce_mm_put(q);
+	mutex_unlock(&uacce->mm_lock);
+
+	kfree(q);
+	module_put(uacce->parent->driver->owner);
+
+	return 0;
+}
+
+static void uacce_vma_close(struct vm_area_struct *vma)
+{
+	struct uacce_queue *q = vma->vm_private_data;
+	struct uacce_qfile_region *qfr = NULL;
+
+	if (vma->vm_pgoff < UACCE_MAX_REGION)
+		qfr = q->qfrs[vma->vm_pgoff];
+
+	kfree(qfr);
+}
+
+static const struct vm_operations_struct uacce_vm_ops = {
+	.close = uacce_vma_close,
+};
+
+static int uacce_fops_mmap(struct file *filep, struct vm_area_struct *vma)
+{
+	struct uacce_queue *q = filep->private_data;
+	struct uacce_device *uacce = q->uacce;
+	struct uacce_qfile_region *qfr;
+	enum uacce_qfrt type = UACCE_MAX_REGION;
+	int ret = 0;
+
+	if (vma->vm_pgoff < UACCE_MAX_REGION)
+		type = vma->vm_pgoff;
+	else
+		return -EINVAL;
+
+	qfr = kzalloc(sizeof(*qfr), GFP_KERNEL);
+	if (!qfr)
+		return -ENOMEM;
+
+	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_WIPEONFORK;
+	vma->vm_ops = &uacce_vm_ops;
+	vma->vm_private_data = q;
+	qfr->type = type;
+
+	mutex_lock(&uacce_mutex);
+
+	if (q->state != UACCE_Q_INIT && q->state != UACCE_Q_STARTED) {
+		ret = -EINVAL;
+		goto out_with_lock;
+	}
+
+	if (q->qfrs[type]) {
+		ret = -EEXIST;
+		goto out_with_lock;
+	}
+
+	switch (type) {
+	case UACCE_QFRT_MMIO:
+		if (!uacce->ops->mmap) {
+			ret = -EINVAL;
+			goto out_with_lock;
+		}
+
+		ret = uacce->ops->mmap(q, vma, qfr);
+		if (ret)
+			goto out_with_lock;
+
+		break;
+
+	case UACCE_QFRT_DUS:
+		if (uacce->flags & UACCE_DEV_SVA) {
+			if (!uacce->ops->mmap) {
+				ret = -EINVAL;
+				goto out_with_lock;
+			}
+
+			ret = uacce->ops->mmap(q, vma, qfr);
+			if (ret)
+				goto out_with_lock;
+		}
+		break;
+
+	default:
+		ret = -EINVAL;
+		goto out_with_lock;
+	}
+
+	q->qfrs[type] = qfr;
+	mutex_unlock(&uacce_mutex);
+
+	return ret;
+
+out_with_lock:
+	mutex_unlock(&uacce_mutex);
+	kfree(qfr);
+	return ret;
+}
+
+static __poll_t uacce_fops_poll(struct file *file, poll_table *wait)
+{
+	struct uacce_queue *q = file->private_data;
+	struct uacce_device *uacce = q->uacce;
+
+	poll_wait(file, &q->wait, wait);
+	if (uacce->ops->is_q_updated && uacce->ops->is_q_updated(q))
+		return EPOLLIN | EPOLLRDNORM;
+
+	return 0;
+}
+
+static const struct file_operations uacce_fops = {
+	.owner		= THIS_MODULE,
+	.open		= uacce_fops_open,
+	.release	= uacce_fops_release,
+	.unlocked_ioctl	= uacce_fops_unl_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= uacce_fops_compat_ioctl,
+#endif
+	.mmap		= uacce_fops_mmap,
+	.poll		= uacce_fops_poll,
+};
+
+#define to_uacce_device(dev) container_of(dev, struct uacce_device, dev)
+
+static ssize_t api_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	return sprintf(buf, "%s\n", uacce->api_ver);
+}
+
+static ssize_t flags_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	return sprintf(buf, "%u\n", uacce->flags);
+}
+
+static ssize_t available_instances_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+	int val = -ENODEV;
+
+	if (uacce->ops->get_available_instances)
+		val = uacce->ops->get_available_instances(uacce);
+
+	return sprintf(buf, "%d\n", val);
+}
+
+static ssize_t algorithms_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	return sprintf(buf, "%s\n", uacce->algs);
+}
+
+static ssize_t region_mmio_size_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	return sprintf(buf, "%lu\n",
+		       uacce->qf_pg_num[UACCE_QFRT_MMIO] << PAGE_SHIFT);
+}
+
+static ssize_t region_dus_size_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	return sprintf(buf, "%lu\n",
+		       uacce->qf_pg_num[UACCE_QFRT_DUS] << PAGE_SHIFT);
+}
+
+static DEVICE_ATTR_RO(api);
+static DEVICE_ATTR_RO(flags);
+static DEVICE_ATTR_RO(available_instances);
+static DEVICE_ATTR_RO(algorithms);
+static DEVICE_ATTR_RO(region_mmio_size);
+static DEVICE_ATTR_RO(region_dus_size);
+
+static struct attribute *uacce_dev_attrs[] = {
+	&dev_attr_api.attr,
+	&dev_attr_flags.attr,
+	&dev_attr_available_instances.attr,
+	&dev_attr_algorithms.attr,
+	&dev_attr_region_mmio_size.attr,
+	&dev_attr_region_dus_size.attr,
+	NULL,
+};
+
+static umode_t uacce_dev_is_visible(struct kobject *kobj,
+				    struct attribute *attr, int n)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	if (((attr == &dev_attr_region_mmio_size.attr) &&
+	    (!uacce->qf_pg_num[UACCE_QFRT_MMIO])) ||
+	    ((attr == &dev_attr_region_dus_size.attr) &&
+	    (!uacce->qf_pg_num[UACCE_QFRT_DUS])))
+		return 0;
+
+	return attr->mode;
+}
+
+static struct attribute_group uacce_dev_group = {
+	.is_visible	= uacce_dev_is_visible,
+	.attrs		= uacce_dev_attrs,
+};
+
+__ATTRIBUTE_GROUPS(uacce_dev);
+
+static void uacce_release(struct device *dev)
+{
+	struct uacce_device *uacce = to_uacce_device(dev);
+
+	kfree(uacce);
+	uacce = NULL;
+}
+
+/**
+ * uacce_alloc() - alloc an accelerator
+ * @parent: pointer of uacce parent device
+ * @interface: pointer of uacce_interface for register
+ *
+ * Returns uacce pointer if success and ERR_PTR if not
+ * Need check returned negotiated uacce->flags
+ */
+struct uacce_device *uacce_alloc(struct device *parent,
+				 struct uacce_interface *interface)
+{
+	unsigned int flags = interface->flags;
+	struct uacce_device *uacce;
+	int ret;
+
+	uacce = kzalloc(sizeof(struct uacce_device), GFP_KERNEL);
+	if (!uacce)
+		return ERR_PTR(-ENOMEM);
+
+	if (flags & UACCE_DEV_SVA) {
+		ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);
+		if (ret)
+			flags &= ~UACCE_DEV_SVA;
+	}
+
+	uacce->parent = parent;
+	uacce->flags = flags;
+	uacce->ops = interface->ops;
+
+	ret = xa_alloc(&uacce_xa, &uacce->dev_id, uacce, xa_limit_32b,
+		       GFP_KERNEL);
+	if (ret < 0)
+		goto err_with_uacce;
+
+	INIT_LIST_HEAD(&uacce->mm_list);
+	mutex_init(&uacce->mm_lock);
+	device_initialize(&uacce->dev);
+	uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);
+	uacce->dev.class = uacce_class;
+	uacce->dev.groups = uacce_dev_groups;
+	uacce->dev.parent = uacce->parent;
+	uacce->dev.release = uacce_release;
+	dev_set_name(&uacce->dev, "%s-%d", interface->name, uacce->dev_id);
+
+	return uacce;
+
+err_with_uacce:
+	if (flags & UACCE_DEV_SVA)
+		iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+	kfree(uacce);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(uacce_alloc);
+
+/**
+ * uacce_register() - add the accelerator to cdev and export to user space
+ * @uacce: The initialized uacce device
+ *
+ * Return 0 if register succeeded, or an error.
+ */
+int uacce_register(struct uacce_device *uacce)
+{
+	if (!uacce)
+		return -ENODEV;
+
+	uacce->cdev = cdev_alloc();
+	if (!uacce->cdev)
+		return -ENOMEM;
+
+	uacce->cdev->ops = &uacce_fops;
+	uacce->cdev->owner = THIS_MODULE;
+
+	return cdev_device_add(uacce->cdev, &uacce->dev);
+}
+EXPORT_SYMBOL_GPL(uacce_register);
+
+/**
+ * uacce_remove() - remove the accelerator
+ * @uacce: the accelerator to remove
+ */
+void uacce_remove(struct uacce_device *uacce)
+{
+	struct uacce_mm *uacce_mm;
+	struct uacce_queue *q;
+
+	if (!uacce)
+		return;
+
+	/* ensure no open queue remains */
+	mutex_lock(&uacce->mm_lock);
+	list_for_each_entry(uacce_mm, &uacce->mm_list, list) {
+		/*
+		 * We don't take the uacce_mm->lock here. Since we hold the
+		 * device's mm_lock, no queue can be added to or removed from
+		 * this uacce_mm. We may run concurrently with mm_exit, but
+		 * uacce_put_queue() is serialized and iommu_sva_unbind_device()
+		 * waits for the lock that mm_exit is holding.
+		 */
+		list_for_each_entry(q, &uacce_mm->queues, list)
+			uacce_put_queue(q);
+
+		if (uacce->flags & UACCE_DEV_SVA) {
+			iommu_sva_unbind_device(uacce_mm->handle);
+			uacce_mm->handle = NULL;
+		}
+	}
+	mutex_unlock(&uacce->mm_lock);
+
+	/* disable sva now since no opened queues */
+	if (uacce->flags & UACCE_DEV_SVA)
+		iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+
+	if (uacce->cdev)
+		cdev_device_del(uacce->cdev, &uacce->dev);
+	xa_erase(&uacce_xa, uacce->dev_id);
+	put_device(&uacce->dev);
+}
+EXPORT_SYMBOL_GPL(uacce_remove);
+
+static int __init uacce_init(void)
+{
+	int ret;
+
+	uacce_class = class_create(THIS_MODULE, UACCE_NAME);
+	if (IS_ERR(uacce_class))
+		return PTR_ERR(uacce_class);
+
+	ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);
+	if (ret)
+		class_destroy(uacce_class);
+
+	return ret;
+}
+
+static __exit void uacce_exit(void)
+{
+	unregister_chrdev_region(uacce_devt, MINORMASK);
+	class_destroy(uacce_class);
+}
+
+subsys_initcall(uacce_init);
+module_exit(uacce_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hisilicon Tech. Co., Ltd.");
+MODULE_DESCRIPTION("Accelerator interface for Userland applications");
diff --git a/include/linux/uacce.h b/include/linux/uacce.h
new file mode 100644
index 0000000..904a461
--- /dev/null
+++ b/include/linux/uacce.h
@@ -0,0 +1,161 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _LINUX_UACCE_H
+#define _LINUX_UACCE_H
+
+#include <linux/cdev.h>
+#include <uapi/misc/uacce/uacce.h>
+
+#define UACCE_NAME		"uacce"
+#define UACCE_MAX_REGION	2
+#define UACCE_MAX_NAME_SIZE	64
+
+struct uacce_queue;
+struct uacce_device;
+
+/**
+ * struct uacce_qfile_region - structure of queue file region
+ * @type: type of the region
+ */
+struct uacce_qfile_region {
+	enum uacce_qfrt type;
+};
+
+/**
+ * struct uacce_ops - uacce device operations
+ * @get_available_instances:  get available instances left of the device
+ * @get_queue: get a queue from the device
+ * @put_queue: free a queue to the device
+ * @start_queue: make the queue start work after get_queue
+ * @stop_queue: make the queue stop work before put_queue
+ * @is_q_updated: check whether the task is finished
+ * @mmap: mmap addresses of queue to user space
+ * @ioctl: ioctl for user space users of the queue
+ */
+struct uacce_ops {
+	int (*get_available_instances)(struct uacce_device *uacce);
+	int (*get_queue)(struct uacce_device *uacce, unsigned long arg,
+			 struct uacce_queue *q);
+	void (*put_queue)(struct uacce_queue *q);
+	int (*start_queue)(struct uacce_queue *q);
+	void (*stop_queue)(struct uacce_queue *q);
+	int (*is_q_updated)(struct uacce_queue *q);
+	int (*mmap)(struct uacce_queue *q, struct vm_area_struct *vma,
+		    struct uacce_qfile_region *qfr);
+	long (*ioctl)(struct uacce_queue *q, unsigned int cmd,
+		      unsigned long arg);
+};
+
+/**
+ * struct uacce_interface - interface required for uacce_register()
+ * @name: the uacce device name.  Will show up in sysfs
+ * @flags: uacce device attributes
+ * @ops: pointer to the struct uacce_ops
+ */
+struct uacce_interface {
+	char name[UACCE_MAX_NAME_SIZE];
+	unsigned int flags;
+	const struct uacce_ops *ops;
+};
+
+enum uacce_q_state {
+	UACCE_Q_ZOMBIE = 0,
+	UACCE_Q_INIT,
+	UACCE_Q_STARTED,
+};
+
+/**
+ * struct uacce_queue
+ * @uacce: pointer to uacce
+ * @priv: private pointer
+ * @wait: wait queue head
+ * @list: index into uacce_mm
+ * @uacce_mm: the corresponding mm
+ * @qfrs: pointer of qfr regions
+ * @state: queue state machine
+ */
+struct uacce_queue {
+	struct uacce_device *uacce;
+	void *priv;
+	wait_queue_head_t wait;
+	struct list_head list;
+	struct uacce_mm *uacce_mm;
+	struct uacce_qfile_region *qfrs[UACCE_MAX_REGION];
+	enum uacce_q_state state;
+};
+
+/**
+ * struct uacce_device
+ * @algs: supported algorithms
+ * @api_ver: api version
+ * @ops: pointer to the struct uacce_ops
+ * @qf_pg_num: page numbers of the queue file regions
+ * @parent: pointer to the parent device
+ * @is_vf: whether virtual function
+ * @flags: uacce attributes
+ * @dev_id: id of the uacce device
+ * @cdev: cdev of the uacce
+ * @dev: dev of the uacce
+ * @priv: private pointer of the uacce
+ * @mm_list: list head of uacce_mm->list
+ * @mm_lock: lock for mm_list
+ */
+struct uacce_device {
+	const char *algs;
+	const char *api_ver;
+	const struct uacce_ops *ops;
+	unsigned long qf_pg_num[UACCE_MAX_REGION];
+	struct device *parent;
+	bool is_vf;
+	u32 flags;
+	u32 dev_id;
+	struct cdev *cdev;
+	struct device dev;
+	void *priv;
+	struct list_head mm_list;
+	struct mutex mm_lock;
+};
+
+/**
+ * struct uacce_mm - keep track of queues bound to a process
+ * @list: index into uacce_device
+ * @queues: list of queues
+ * @mm: the mm struct
+ * @lock: protects the list of queues
+ * @pasid: pasid of the uacce_mm
+ * @handle: iommu_sva handle return from iommu_sva_bind_device
+ */
+struct uacce_mm {
+	struct list_head list;
+	struct list_head queues;
+	struct mm_struct *mm;
+	struct mutex lock;
+	int pasid;
+	struct iommu_sva *handle;
+};
+
+#if IS_ENABLED(CONFIG_UACCE)
+
+struct uacce_device *uacce_alloc(struct device *parent,
+				 struct uacce_interface *interface);
+int uacce_register(struct uacce_device *uacce);
+void uacce_remove(struct uacce_device *uacce);
+
+#else /* CONFIG_UACCE */
+
+static inline
+struct uacce_device *uacce_alloc(struct device *parent,
+				 struct uacce_interface *interface)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline int uacce_register(struct uacce_device *uacce)
+{
+	return -EINVAL;
+}
+
+static inline void uacce_remove(struct uacce_device *uacce) {}
+
+#endif /* CONFIG_UACCE */
+
+#endif /* _LINUX_UACCE_H */
diff --git a/include/uapi/misc/uacce/uacce.h b/include/uapi/misc/uacce/uacce.h
new file mode 100644
index 0000000..cc71856
--- /dev/null
+++ b/include/uapi/misc/uacce/uacce.h
@@ -0,0 +1,38 @@ 
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+#ifndef _UAPIUUACCE_H
+#define _UAPIUUACCE_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/*
+ * UACCE_CMD_START_Q: Start queue
+ */
+#define UACCE_CMD_START_Q	_IO('W', 0)
+
+/*
+ * UACCE_CMD_PUT_Q:
+ * User actively stop queue and free queue resource immediately
+ * Optimization method since close fd may delay
+ */
+#define UACCE_CMD_PUT_Q		_IO('W', 1)
+
+/*
+ * UACCE Device flags:
+ * UACCE_DEV_SVA: Shared Virtual Addresses
+ *		  Support PASID
+ *		  Support device page faults (PCI PRI or SMMU Stall)
+ */
+#define UACCE_DEV_SVA		BIT(0)
+
+/**
+ * enum uacce_qfrt: queue file region type
+ * @UACCE_QFRT_MMIO: device mmio region
+ * @UACCE_QFRT_DUS: device user share region
+ */
+enum uacce_qfrt {
+	UACCE_QFRT_MMIO = 0,
+	UACCE_QFRT_DUS = 1,
+};
+
+#endif