[v3,2/2] uacce: add uacce driver

Message ID 1567484087-8071-2-git-send-email-zhangfei.gao@linaro.org
State New
Headers show
Series
  • Add uacce module for Accelerator
Related show

Commit Message

zhangfei Sept. 3, 2019, 4:14 a.m.
From: Kenneth Lee <liguozhu@hisilicon.com>


Uacce (Unified/User-space-access-intended Accelerator Framework) targets to
provide Shared Virtual Addressing (SVA) between accelerators and processes.
So accelerator can access any data structure of the main cpu.
This differs from the data sharing between cpu and io device, which share
data content rather than address.
Since unified address, hardware and user space of process can share the
same virtual address in the communication.

Uacce create a chrdev for every registration, the queue is allocated to
the process when the chrdev is opened. Then the process can access the
hardware resource by interact with the queue file. By mmap the queue
file space to user space, the process can directly put requests to the
hardware without syscall to the kernel space.

Signed-off-by: Kenneth Lee <liguozhu@hisilicon.com>

Signed-off-by: Zaibo Xu <xuzaibo@huawei.com>

Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>

Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>

---
 Documentation/ABI/testing/sysfs-driver-uacce |   47 ++
 drivers/misc/Kconfig                         |    1 +
 drivers/misc/Makefile                        |    1 +
 drivers/misc/uacce/Kconfig                   |   13 +
 drivers/misc/uacce/Makefile                  |    2 +
 drivers/misc/uacce/uacce.c                   | 1096 ++++++++++++++++++++++++++
 include/linux/uacce.h                        |  172 ++++
 include/uapi/misc/uacce.h                    |   39 +
 8 files changed, 1371 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-uacce
 create mode 100644 drivers/misc/uacce/Kconfig
 create mode 100644 drivers/misc/uacce/Makefile
 create mode 100644 drivers/misc/uacce/uacce.c
 create mode 100644 include/linux/uacce.h
 create mode 100644 include/uapi/misc/uacce.h

-- 
2.7.4

Comments

Greg KH Sept. 4, 2019, 12:38 p.m. | #1
On Tue, Sep 03, 2019 at 12:14:47PM +0800, Zhangfei Gao wrote:
> From: Kenneth Lee <liguozhu@hisilicon.com>

> 

> Uacce (Unified/User-space-access-intended Accelerator Framework) targets to

> provide Shared Virtual Addressing (SVA) between accelerators and processes.

> So accelerator can access any data structure of the main cpu.

> This differs from the data sharing between cpu and io device, which share

> data content rather than address.

> Since unified address, hardware and user space of process can share the

> same virtual address in the communication.

> 

> Uacce create a chrdev for every registration, the queue is allocated to

> the process when the chrdev is opened. Then the process can access the

> hardware resource by interact with the queue file. By mmap the queue

> file space to user space, the process can directly put requests to the

> hardware without syscall to the kernel space.

> 

> Signed-off-by: Kenneth Lee <liguozhu@hisilicon.com>

> Signed-off-by: Zaibo Xu <xuzaibo@huawei.com>

> Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>

> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>

> ---

>  Documentation/ABI/testing/sysfs-driver-uacce |   47 ++

>  drivers/misc/Kconfig                         |    1 +

>  drivers/misc/Makefile                        |    1 +

>  drivers/misc/uacce/Kconfig                   |   13 +

>  drivers/misc/uacce/Makefile                  |    2 +

>  drivers/misc/uacce/uacce.c                   | 1096 ++++++++++++++++++++++++++

>  include/linux/uacce.h                        |  172 ++++

>  include/uapi/misc/uacce.h                    |   39 +

>  8 files changed, 1371 insertions(+)

>  create mode 100644 Documentation/ABI/testing/sysfs-driver-uacce

>  create mode 100644 drivers/misc/uacce/Kconfig

>  create mode 100644 drivers/misc/uacce/Makefile

>  create mode 100644 drivers/misc/uacce/uacce.c

>  create mode 100644 include/linux/uacce.h

>  create mode 100644 include/uapi/misc/uacce.h

> 

> diff --git a/Documentation/ABI/testing/sysfs-driver-uacce b/Documentation/ABI/testing/sysfs-driver-uacce

> new file mode 100644

> index 0000000..ee0a66e

> --- /dev/null

> +++ b/Documentation/ABI/testing/sysfs-driver-uacce

> @@ -0,0 +1,47 @@

> +What:           /sys/class/uacce/hisi_zip-<n>/id

> +Date:           Sep 2019

> +KernelVersion:  5.3


5.3 will be released in a week or so, without this file in it, so that's
not ok here :(
Greg KH Sept. 4, 2019, 12:50 p.m. | #2
On Tue, Sep 03, 2019 at 12:14:47PM +0800, Zhangfei Gao wrote:
> +/**

> + * uacce_wake_up - Wake up the process who is waiting this queue

> + * @q the accelerator queue to wake up

> + */

> +void uacce_wake_up(struct uacce_queue *q)

> +{

> +	wake_up_interruptible(&q->wait);

> +}

> +EXPORT_SYMBOL_GPL(uacce_wake_up);


You are exporting things that have no in-kernel user, which is not
allowed.

Can you redo this patch series with an actual user of this new api you
are creating?  Otherwise we have no way of properly understanding just
what is going on here.

Also, do you really need a function to do the above?  Why?

> +static int uacce_dev_open_check(struct uacce_device *uacce)

> +{

> +	/*

> +	 * The device can be opened once if it dose not support pasid

> +	 */

> +	if (uacce->flags & UACCE_DEV_PASID)

> +		return 0;

> +

> +	if (atomic_cmpxchg(&uacce->state, UACCE_ST_INIT, UACCE_ST_OPENED) !=

> +	    UACCE_ST_INIT) {

> +		dev_info(&uacce->dev, "this device can be openned only once\n");


No, NEVER do this, it's wrong, an easy way to spam the syslog for no
good reason, and flat out does not work at all.

Just let userspace deal with something like this, if they want to open
multiple times, let it deal with the fallout.  Just like a tty device
node.



> +		return -EBUSY;

> +	}

> +

> +	return 0;

> +}

> +

> +static int uacce_fops_open(struct inode *inode, struct file *filep)

> +{

> +	struct uacce_queue *q;

> +	struct iommu_sva *handle = NULL;

> +	struct uacce_device *uacce;

> +	int ret;

> +	int pasid = 0;

> +

> +	uacce = idr_find(&uacce_idr, iminor(inode));

> +	if (!uacce)

> +		return -ENODEV;

> +

> +	if (atomic_read(&uacce->state) == UACCE_ST_RST)

> +		return -EINVAL;


What happens if the state changes _right_ after this check?

> +

> +	if ((!uacce->ops->get_queue) || (!uacce->ops->start_queue))

> +		return -EINVAL;


How would these two functions ever not be NULL?

Why check for them in open()?  Why not when you register the operations?

> +	if (!try_module_get(uacce->pdev->driver->owner))

> +		return -ENODEV;

> +

> +	ret = uacce_dev_open_check(uacce);

> +	if (ret)

> +		goto open_err;

> +

> +#ifdef CONFIG_IOMMU_SVA

> +	if (uacce->flags & UACCE_DEV_PASID) {

> +		handle = iommu_sva_bind_device(uacce->pdev, current->mm, NULL);

> +		if (IS_ERR(handle))

> +			goto open_err;

> +		pasid = iommu_sva_get_pasid(handle);

> +	}

> +#endif

> +	ret = uacce->ops->get_queue(uacce, pasid, &q);

> +	if (ret < 0)

> +		goto open_err;

> +

> +	q->pasid = pasid;

> +	q->handle = handle;

> +	q->uacce = uacce;

> +	q->mm = current->mm;

> +	memset(q->qfrs, 0, sizeof(q->qfrs));

> +	INIT_LIST_HEAD(&q->list);

> +	init_waitqueue_head(&q->wait);

> +	filep->private_data = q;

> +	mutex_lock(&uacce->q_lock);

> +	list_add(&q->q_dev, &uacce->qs);

> +	mutex_unlock(&uacce->q_lock);

> +

> +	return 0;

> +

> +open_err:

> +	module_put(uacce->pdev->driver->owner);

> +	return ret;

> +}

> +

> +static int uacce_fops_release(struct inode *inode, struct file *filep)

> +{

> +	struct uacce_queue *q = filep->private_data;

> +	struct uacce_qfile_region *qfr;

> +	struct uacce_device *uacce = q->uacce;

> +	bool is_to_free_region;

> +	int free_pages = 0;

> +	int i;

> +

> +	mutex_lock(&uacce->q_lock);

> +	list_del(&q->q_dev);

> +	mutex_unlock(&uacce->q_lock);

> +

> +	if (atomic_read(&uacce->state) == UACCE_ST_STARTED &&

> +	    uacce->ops->stop_queue)

> +		uacce->ops->stop_queue(q);


Same question as before, what happens right after this check?

Do not use an atomic value thinking it is how to properly test for state
changes.  Use a "real" lock for this, otherwise it does not work at all.

> +

> +	mutex_lock(&uacce_mutex);

> +

> +	for (i = 0; i < UACCE_QFRT_MAX; i++) {

> +		qfr = q->qfrs[i];

> +		if (!qfr)

> +			continue;

> +

> +		is_to_free_region = false;

> +		uacce_queue_unmap_qfr(q, qfr);

> +		if (i == UACCE_QFRT_SS) {

> +			list_del(&q->list);

> +			if (list_empty(&qfr->qs))

> +				is_to_free_region = true;

> +		} else

> +			is_to_free_region = true;

> +

> +		if (is_to_free_region) {

> +			free_pages += qfr->nr_pages;

> +			uacce_destroy_region(q, qfr);

> +		}

> +

> +		qfr = NULL;

> +	}

> +

> +	mutex_unlock(&uacce_mutex);

> +

> +	if (current->mm == q->mm) {

> +		down_write(&q->mm->mmap_sem);

> +		q->mm->data_vm -= free_pages;

> +		up_write(&q->mm->mmap_sem);

> +	}

> +

> +#ifdef CONFIG_IOMMU_SVA

> +	if (uacce->flags & UACCE_DEV_PASID)

> +		iommu_sva_unbind_device(q->handle);

> +#endif

> +

> +	if (uacce->ops->put_queue)

> +		uacce->ops->put_queue(q);

> +

> +	atomic_set(&uacce->state, UACCE_ST_INIT);

> +	module_put(uacce->pdev->driver->owner);

> +

> +	return 0;

> +}

> +

> +static enum uacce_qfrt uacce_get_region_type(struct uacce_device *uacce,

> +					     struct vm_area_struct *vma)

> +{

> +	enum uacce_qfrt type = UACCE_QFRT_MAX;

> +	size_t next_start = UACCE_QFR_NA;

> +	int i;

> +

> +	for (i = UACCE_QFRT_MAX - 1; i >= 0; i--) {

> +		if (vma->vm_pgoff >= uacce->qf_pg_start[i]) {

> +			type = i;

> +			break;

> +		}

> +	}

> +

> +	switch (type) {

> +	case UACCE_QFRT_MMIO:

> +		if (!uacce->ops->mmap) {

> +			dev_err(&uacce->dev, "no driver mmap!\n");

> +			return UACCE_QFRT_MAX;


You not return an error?

> +		}

> +		break;

> +

> +	case UACCE_QFRT_DKO:

> +		if (uacce->flags & UACCE_DEV_PASID)

> +			return UACCE_QFRT_MAX;


Same here, no error?

> +		break;

> +

> +	case UACCE_QFRT_DUS:

> +		break;

> +

> +	case UACCE_QFRT_SS:

> +		/* todo: this can be valid to protect the process space */

> +		if (uacce->flags & UACCE_DEV_FAULT_FROM_DEV)

> +			return UACCE_QFRT_MAX;


error?

> +		break;

> +

> +	default:

> +		dev_err(&uacce->dev, "uacce bug (%d)!\n", type);


Are you now allowing userspace to spam the kernel log if you send it
random crud?

> +		return UACCE_QFRT_MAX;


Return a proper error here and lots of other places.

> +	}

> +

> +	/* make sure the mapping size is exactly the same as the region */

> +	if (type < UACCE_QFRT_SS) {

> +		for (i = type + 1; i < UACCE_QFRT_MAX; i++)

> +			if (uacce->qf_pg_start[i] != UACCE_QFR_NA) {

> +				next_start = uacce->qf_pg_start[i];

> +				break;

> +			}

> +

> +		if (next_start == UACCE_QFR_NA) {

> +			dev_err(&uacce->dev, "uacce config error: SS offset set improperly\n");

> +			return UACCE_QFRT_MAX;

> +		}

> +

> +		if (vma_pages(vma) !=

> +		    next_start - uacce->qf_pg_start[type]) {

> +			dev_err(&uacce->dev, "invalid mmap size (%ld vs %ld pages) for region %s.\n",

> +				vma_pages(vma),

> +				next_start - uacce->qf_pg_start[type],

> +				qfrt_str[type]);

> +			return UACCE_QFRT_MAX;

> +		}

> +	}

> +

> +	return type;

> +}

> +

> +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;

> +	enum uacce_qfrt type = uacce_get_region_type(uacce, vma);

> +	struct uacce_qfile_region *qfr;

> +	unsigned int flags = 0;

> +	int ret;

> +

> +	if (type == UACCE_QFRT_MAX)

> +		return -EINVAL;

> +

> +	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;

> +

> +	mutex_lock(&uacce_mutex);

> +

> +	/* fixme: if the region need no pages, we don't need to check it */

> +	if (q->mm->data_vm + vma_pages(vma) >

> +	    rlimit(RLIMIT_DATA) >> PAGE_SHIFT) {

> +		ret = -ENOMEM;

> +		goto out_with_lock;

> +	}

> +

> +	if (q->qfrs[type]) {

> +		ret = -EBUSY;

> +		goto out_with_lock;

> +	}

> +

> +	switch (type) {

> +	case UACCE_QFRT_MMIO:

> +		flags = UACCE_QFRF_SELFMT;

> +		break;

> +

> +	case UACCE_QFRT_SS:

> +		if (atomic_read(&uacce->state) != UACCE_ST_STARTED) {

> +			ret = -EINVAL;

> +			goto out_with_lock;

> +		}

> +

> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;

> +

> +		break;

> +

> +	case UACCE_QFRT_DKO:

> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_KMAP;

> +

> +		break;

> +

> +	case UACCE_QFRT_DUS:

> +		if (uacce->flags & UACCE_DEV_PASID) {

> +			flags = UACCE_QFRF_SELFMT;

> +			break;

> +		}

> +

> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;

> +		break;

> +

> +	default:

> +		WARN_ON(&uacce->dev);

> +		break;

> +	}

> +

> +	qfr = uacce_create_region(q, vma, type, flags);

> +	if (IS_ERR(qfr)) {

> +		ret = PTR_ERR(qfr);

> +		goto out_with_lock;

> +	}

> +	q->qfrs[type] = qfr;

> +

> +	if (type == UACCE_QFRT_SS) {

> +		INIT_LIST_HEAD(&qfr->qs);

> +		list_add(&q->list, &q->qfrs[type]->qs);

> +	}

> +

> +	mutex_unlock(&uacce_mutex);

> +

> +	if (qfr->pages)

> +		q->mm->data_vm += qfr->nr_pages;

> +

> +	return 0;

> +

> +out_with_lock:

> +	mutex_unlock(&uacce_mutex);

> +	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 UACCE_FROM_CDEV_ATTR(dev) container_of(dev, struct uacce_device, dev)

> +

> +static ssize_t id_show(struct device *dev,

> +		       struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);


FROM_CDEV?  But that's not a cdev.  I'm confused.  Pick a better name
for your macro please.

> +

> +	return sprintf(buf, "%d\n", uacce->dev_id);

> +}

> +

> +static ssize_t api_show(struct device *dev,

> +			struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +

> +	return sprintf(buf, "%s\n", uacce->api_ver);

> +}

> +

> +static ssize_t numa_distance_show(struct device *dev,

> +				  struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +	int distance;

> +

> +	distance = node_distance(smp_processor_id(), uacce->pdev->numa_node);

> +

> +	return sprintf(buf, "%d\n", abs(distance));

> +}

> +

> +static ssize_t node_id_show(struct device *dev,

> +			    struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +	int node_id;

> +

> +	node_id = dev_to_node(uacce->pdev);

> +

> +	return sprintf(buf, "%d\n", node_id);

> +}

> +

> +static ssize_t flags_show(struct device *dev,

> +			  struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +

> +	return sprintf(buf, "%d\n", uacce->flags);

> +}

> +

> +static ssize_t available_instances_show(struct device *dev,

> +					struct device_attribute *attr,

> +					char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +	int val = 0;

> +

> +	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 = UACCE_FROM_CDEV_ATTR(dev);

> +

> +	return sprintf(buf, "%s", uacce->algs);

> +}

> +

> +static ssize_t qfrs_offset_show(struct device *dev,

> +				struct device_attribute *attr, char *buf)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +	int i, ret;

> +	unsigned long offset;

> +

> +	for (i = 0, ret = 0; i < UACCE_QFRT_MAX; i++) {

> +		offset = uacce->qf_pg_start[i];

> +		if (offset != UACCE_QFR_NA)

> +			offset = offset << PAGE_SHIFT;

> +		if (i == UACCE_QFRT_SS)

> +			break;

> +		ret += sprintf(buf + ret, "%lu\t", offset);

> +	}

> +	ret += sprintf(buf + ret, "%lu\n", offset);

> +

> +	return ret;

> +}

> +

> +static DEVICE_ATTR_RO(id);

> +static DEVICE_ATTR_RO(api);

> +static DEVICE_ATTR_RO(numa_distance);

> +static DEVICE_ATTR_RO(node_id);

> +static DEVICE_ATTR_RO(flags);

> +static DEVICE_ATTR_RO(available_instances);

> +static DEVICE_ATTR_RO(algorithms);

> +static DEVICE_ATTR_RO(qfrs_offset);

> +

> +static struct attribute *uacce_dev_attrs[] = {

> +	&dev_attr_id.attr,

> +	&dev_attr_api.attr,

> +	&dev_attr_node_id.attr,

> +	&dev_attr_numa_distance.attr,

> +	&dev_attr_flags.attr,

> +	&dev_attr_available_instances.attr,

> +	&dev_attr_algorithms.attr,

> +	&dev_attr_qfrs_offset.attr,

> +	NULL,

> +};

> +

> +static const struct attribute_group uacce_dev_attr_group = {

> +	.attrs	= uacce_dev_attrs,

> +};

> +

> +static const struct attribute_group *uacce_dev_attr_groups[] = {

> +	&uacce_dev_attr_group,

> +	NULL

> +};


ATTRIBUTE_GROUPS()?

> +

> +static void uacce_release(struct device *dev)

> +{

> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> +

> +	idr_remove(&uacce_idr, uacce->dev_id);

> +	kfree(uacce);

> +}

> +

> +static int uacce_create_chrdev(struct uacce_device *uacce)


You do more than just that here, you should rename the function.

> +{

> +	int ret;

> +

> +	ret = idr_alloc(&uacce_idr, uacce, 0, 0, GFP_KERNEL);

> +	if (ret < 0)

> +		return ret;

> +

> +	uacce->cdev = cdev_alloc();

> +	uacce->cdev->ops = &uacce_fops;

> +	uacce->dev_id = ret;

> +	uacce->cdev->owner = THIS_MODULE;

> +	device_initialize(&uacce->dev);

> +	uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);

> +	uacce->dev.class = uacce_class;

> +	uacce->dev.groups = uacce_dev_attr_groups;

> +	uacce->dev.parent = uacce->pdev;

> +	uacce->dev.release = uacce_release;

> +	dev_set_name(&uacce->dev, "%s-%d", uacce->drv_name, uacce->dev_id);

> +	ret = cdev_device_add(uacce->cdev, &uacce->dev);

> +	if (ret)

> +		goto err_with_idr;

> +

> +	dev_dbg(&uacce->dev, "create uacce minior=%d\n", uacce->dev_id);

> +

> +	return 0;

> +

> +err_with_idr:

> +	idr_remove(&uacce_idr, uacce->dev_id);

> +	return ret;

> +}

> +

> +static void uacce_destroy_chrdev(struct uacce_device *uacce)

> +{

> +	cdev_device_del(uacce->cdev, &uacce->dev);

> +	put_device(&uacce->dev);


Again, drop the _chrdev in the function name.

> +}

> +

> +static int uacce_dev_match(struct device *dev, void *data)

> +{

> +	if (dev->parent == data)

> +		return -EBUSY;

> +

> +	return 0;


Do you really need this?

> +}

> +

> +/* Borrowed from VFIO to fix msi translation */

> +static bool uacce_iommu_has_sw_msi(struct iommu_group *group,

> +				   phys_addr_t *base)

> +{

> +	struct list_head group_resv_regions;

> +	struct iommu_resv_region *region, *next;

> +	bool ret = false;

> +

> +	INIT_LIST_HEAD(&group_resv_regions);

> +	iommu_get_group_resv_regions(group, &group_resv_regions);

> +	list_for_each_entry(region, &group_resv_regions, list) {

> +		pr_debug("uacce: find a resv region (%d) on %llx\n",

> +			 region->type, region->start);

> +

> +		/*

> +		 * The presence of any 'real' MSI regions should take

> +		 * precedence over the software-managed one if the

> +		 * IOMMU driver happens to advertise both types.

> +		 */

> +		if (region->type == IOMMU_RESV_MSI) {

> +			ret = false;

> +			break;

> +		}

> +

> +		if (region->type == IOMMU_RESV_SW_MSI) {

> +			*base = region->start;

> +			ret = true;

> +		}

> +	}

> +	list_for_each_entry_safe(region, next, &group_resv_regions, list)

> +		kfree(region);

> +

> +	return ret;

> +}

> +

> +static int uacce_set_iommu_domain(struct uacce_device *uacce)

> +{

> +	struct iommu_domain *domain;

> +	struct iommu_group *group;

> +	struct device *dev = uacce->pdev;

> +	bool resv_msi;

> +	phys_addr_t resv_msi_base = 0;

> +	int ret;

> +

> +	if (uacce->flags & UACCE_DEV_PASID)

> +		return 0;

> +

> +	/*

> +	 * We don't support multiple register for the same dev if no pasid

> +	 */

> +	ret = class_for_each_device(uacce_class, NULL, uacce->pdev,

> +				    uacce_dev_match);

> +	if (ret)

> +		return ret;

> +

> +	/* allocate and attach a unmanged domain */

> +	domain = iommu_domain_alloc(uacce->pdev->bus);

> +	if (!domain) {

> +		dev_err(&uacce->dev, "cannot get domain for iommu\n");

> +		return -ENODEV;

> +	}

> +

> +	ret = iommu_attach_device(domain, uacce->pdev);

> +	if (ret)

> +		goto err_with_domain;

> +

> +	if (iommu_capable(dev->bus, IOMMU_CAP_CACHE_COHERENCY))

> +		uacce->prot |= IOMMU_CACHE;

> +

> +	group = iommu_group_get(dev);

> +	if (!group) {

> +		ret = -EINVAL;

> +		goto err_with_domain;

> +	}

> +

> +	resv_msi = uacce_iommu_has_sw_msi(group, &resv_msi_base);

> +	iommu_group_put(group);

> +

> +	if (resv_msi) {

> +		if (!irq_domain_check_msi_remap() &&

> +		    !iommu_capable(dev->bus, IOMMU_CAP_INTR_REMAP)) {

> +			dev_warn(dev, "No interrupt remapping support!");

> +			ret = -EPERM;

> +			goto err_with_domain;

> +		}

> +

> +		ret = iommu_get_msi_cookie(domain, resv_msi_base);

> +		if (ret)

> +			goto err_with_domain;

> +	}

> +

> +	return 0;

> +

> +err_with_domain:

> +	iommu_domain_free(domain);

> +	return ret;

> +}

> +

> +static void uacce_unset_iommu_domain(struct uacce_device *uacce)

> +{

> +	struct iommu_domain *domain;

> +

> +	if (uacce->flags & UACCE_DEV_PASID)

> +		return;

> +

> +	domain = iommu_get_domain_for_dev(uacce->pdev);

> +	if (!domain) {

> +		dev_err(&uacce->dev, "bug: no domain attached to device\n");

> +		return;

> +	}

> +

> +	iommu_detach_device(domain, uacce->pdev);

> +	iommu_domain_free(domain);

> +}

> +

> +/**

> + *	uacce_register - register an accelerator

> + *	@uacce: the accelerator structure

> + */

> +struct uacce_device *uacce_register(struct device *parent,

> +				    struct uacce_interface *interface)

> +{

> +	int ret, i;

> +	struct uacce_device *uacce;

> +	unsigned int flags = interface->flags;

> +

> +	/* if dev support fault-from-dev, it should support pasid */

> +	if ((flags & UACCE_DEV_FAULT_FROM_DEV) && !(flags & UACCE_DEV_PASID)) {

> +		dev_warn(parent, "SVM/SAV device should support PASID\n");

> +		return ERR_PTR(-EINVAL);

> +	}

> +

> +#ifdef CONFIG_IOMMU_SVA

> +	if (flags & UACCE_DEV_PASID) {

> +		ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);

> +		if (ret)

> +			flags &= ~(UACCE_DEV_FAULT_FROM_DEV |

> +				   UACCE_DEV_PASID);

> +	}

> +#endif

> +	uacce = kzalloc(sizeof(struct uacce_device), GFP_KERNEL);

> +	if (!uacce)

> +		return ERR_PTR(-ENOMEM);

> +

> +	uacce->pdev = parent;

> +	uacce->flags = flags;

> +	uacce->ops = interface->ops;

> +	uacce->drv_name = interface->name;

> +

> +	for (i = 0; i < UACCE_QFRT_MAX; i++)

> +		uacce->qf_pg_start[i] = UACCE_QFR_NA;

> +

> +	ret = uacce_set_iommu_domain(uacce);

> +	if (ret)

> +		goto err_free;

> +

> +	mutex_lock(&uacce_mutex);

> +

> +	ret = uacce_create_chrdev(uacce);

> +	if (ret)

> +		goto err_with_lock;

> +

> +	atomic_set(&uacce->state, UACCE_ST_INIT);

> +	INIT_LIST_HEAD(&uacce->qs);

> +	mutex_init(&uacce->q_lock);

> +

> +	mutex_unlock(&uacce_mutex);

> +

> +	return uacce;

> +

> +err_with_lock:

> +	mutex_unlock(&uacce_mutex);

> +err_free:

> +	kfree(uacce);

> +	return ERR_PTR(ret);

> +}

> +EXPORT_SYMBOL_GPL(uacce_register);

> +

> +/**

> + * uacce_unregister - unregisters a uacce

> + * @uacce: the accelerator to unregister

> + *

> + * Unregister an accelerator that wat previously successully registered with

> + * uacce_register().

> + */

> +void uacce_unregister(struct uacce_device *uacce)

> +{

> +	mutex_lock(&uacce_mutex);

> +

> +#ifdef CONFIG_IOMMU_SVA

> +	if (uacce->flags & UACCE_DEV_PASID)

> +		iommu_dev_disable_feature(uacce->pdev, IOMMU_DEV_FEAT_SVA);

> +#endif

> +	uacce_unset_iommu_domain(uacce);

> +	uacce_destroy_chrdev(uacce);

> +

> +	mutex_unlock(&uacce_mutex);

> +}

> +EXPORT_SYMBOL_GPL(uacce_unregister);

> +

> +static int __init uacce_init(void)

> +{

> +	int ret;

> +

> +	uacce_class = class_create(THIS_MODULE, UACCE_NAME);

> +	if (IS_ERR(uacce_class)) {

> +		ret = PTR_ERR(uacce_class);

> +		goto err;

> +	}

> +

> +	ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);

> +	if (ret)

> +		goto err_with_class;

> +

> +	pr_info("uacce init with major number:%d\n", MAJOR(uacce_devt));


When your code works properly, it is totally silent.  Do not spam the
kernel log for no good reason.  Stuff like this is debugging only, if
that as you can see it in the proper /proc/ file.

> +

> +	return 0;

> +

> +err_with_class:

> +	class_destroy(uacce_class);

> +err:

> +	return ret;

> +}

> +

> +static __exit void uacce_exit(void)

> +{

> +	unregister_chrdev_region(uacce_devt, MINORMASK);

> +	class_destroy(uacce_class);

> +	idr_destroy(&uacce_idr);

> +}

> +

> +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..b23a28b

> --- /dev/null

> +++ b/include/linux/uacce.h

> @@ -0,0 +1,172 @@

> +/* SPDX-License-Identifier: GPL-2.0-or-later */

> +#ifndef __UACCE_H

> +#define __UACCE_H

> +

> +#include <linux/cdev.h>

> +#include <linux/device.h>

> +#include <linux/fs.h>

> +#include <linux/list.h>

> +#include <linux/iommu.h>

> +#include <uapi/misc/uacce.h>


Why are all of these needed in this .h file?  Are you sure?

> +

> +#define UACCE_NAME		"uacce"

> +

> +struct uacce_queue;

> +struct uacce_device;

> +

> +/* uacce mode of the driver */

> +#define UACCE_MODE_NOUACCE	0 /* don't use uacce */

> +#define UACCE_MODE_UACCE	1 /* use uacce exclusively */

> +

> +/* uacce queue file flag, requires different operation */

> +#define UACCE_QFRF_MAP		BIT(0)	/* map to current queue */

> +#define UACCE_QFRF_MMAP		BIT(1)	/* map to user space */

> +#define UACCE_QFRF_KMAP		BIT(2)	/* map to kernel space */

> +#define UACCE_QFRF_DMA		BIT(3)	/* use dma api for the region */

> +#define UACCE_QFRF_SELFMT	BIT(4)	/* self maintained qfr */

> +

> +/**

> + * struct uacce_qfile_region - structure of queue file region

> + * @type: type of the qfr

> + * @iova: iova share between user and device space

> + * @pages: pages pointer of the qfr memory

> + * @nr_pages: page numbers of the qfr memory

> + * @prot: qfr protection flag

> + * @flags: flags of qfr

> + * @qs: list sharing the same region, for ss region

> + * @kaddr: kernel addr of the qfr

> + * @dma: dma address, if created by dma api

> + */

> +struct uacce_qfile_region {

> +	enum uacce_qfrt type;

> +	unsigned long iova;

> +	struct page **pages;

> +	int nr_pages;

> +	int prot;

> +	unsigned int flags;

> +	struct list_head qs;

> +	void *kaddr;

> +	dma_addr_t dma;

> +};

> +

> +/**

> + * 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

> + * @mask_notify: mask the task irq of queue

> + * @mmap: mmap addresses of queue to user space

> + * @reset: reset the uacce device

> + * @reset_queue: reset the queue

> + * @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);

> +	void (*mask_notify)(struct uacce_queue *q, int event_mask);

> +	int (*mmap)(struct uacce_queue *q, struct vm_area_struct *vma,

> +		    struct uacce_qfile_region *qfr);

> +	int (*reset)(struct uacce_device *uacce);

> +	int (*reset_queue)(struct uacce_queue *q);

> +	long (*ioctl)(struct uacce_queue *q, unsigned int cmd,

> +		      unsigned long arg);

> +};

> +

> +/**

> + * struct uacce_interface

> + * @name: the uacce device name.  Will show up in sysfs

> + * @flags: uacce device attributes

> + * @ops: pointer to the struct uacce_ops

> + *

> + * This structure is used for the uacce_register()

> + */

> +struct uacce_interface {

> +	char name[32];

> +	unsigned int flags;

> +	struct uacce_ops *ops;

> +};

> +

> +/**

> + * struct uacce_queue

> + * @uacce: pointer to uacce

> + * @priv: private pointer

> + * @wait: wait queue head

> + * @pasid: pasid of the queue

> + * @handle: iommu_sva handle return from iommu_sva_bind_device

> + * @list: share list for qfr->qs

> + * @mm: current->mm

> + * @qfrs: pointer of qfr regions

> + * @q_dev: list for uacce->qs

> + */

> +struct uacce_queue {

> +	struct uacce_device *uacce;

> +	void *priv;

> +	wait_queue_head_t wait;

> +	int pasid;

> +	struct iommu_sva *handle;

> +	struct list_head list;

> +	struct mm_struct *mm;

> +	struct uacce_qfile_region *qfrs[UACCE_QFRT_MAX];

> +	struct list_head q_dev;

> +};

> +

> +/* uacce state */

> +enum {

> +	UACCE_ST_INIT = 0,

> +	UACCE_ST_OPENED,

> +	UACCE_ST_STARTED,

> +	UACCE_ST_RST,

> +};

> +

> +/**

> + * struct uacce_device

> + * @drv_name: the uacce driver name.  Will show up in sysfs

> + * @algs: supported algorithms

> + * @api_ver: api version

> + * @flags: uacce attributes

> + * @qf_pg_start: page start of the queue file regions

> + * @ops: pointer to the struct uacce_ops

> + * @pdev: pointer to the parent device

> + * @is_vf: whether virtual function

> + * @dev_id: id of the uacce device

> + * @cdev: cdev of the uacce

> + * @dev: dev of the uacce

> + * @priv: private pointer of the uacce

> + * @state: uacce state

> + * @prot: uacce protection flag

> + * @q_lock: uacce mutex lock for queue

> + * @qs: uacce list head for share

> + */

> +struct uacce_device {

> +	const char *drv_name;


A driver is bound to a device, and you can get the name there.  No need
for it to be here.

> +	const char *algs;

> +	const char *api_ver;

> +	unsigned int flags;


u64?

> +	unsigned long qf_pg_start[UACCE_QFRT_MAX];

> +	struct uacce_ops *ops;

> +	struct device *pdev;

> +	bool is_vf;

> +	u32 dev_id;

> +	struct cdev *cdev;

> +	struct device dev;

> +	void *priv;

> +	atomic_t state;

> +	int prot;


u32?


> +	struct mutex q_lock;

> +	struct list_head qs;


What's wrong with the list in the device itself?

> +};

> +

> +struct uacce_device *uacce_register(struct device *parent,

> +				    struct uacce_interface *interface);

> +void uacce_unregister(struct uacce_device *uacce);

> +void uacce_wake_up(struct uacce_queue *q);

> +

> +#endif

> diff --git a/include/uapi/misc/uacce.h b/include/uapi/misc/uacce.h

> new file mode 100644

> index 0000000..685b4a1

> --- /dev/null

> +++ b/include/uapi/misc/uacce.h

> @@ -0,0 +1,39 @@

> +/* SPDX-License-Identifier: GPL-2.0-or-later */

> +#ifndef _UAPIUUACCE_H

> +#define _UAPIUUACCE_H

> +

> +#include <linux/types.h>

> +#include <linux/ioctl.h>

> +

> +#define UACCE_CMD_SHARE_SVAS	_IO('W', 0)

> +#define UACCE_CMD_START		_IO('W', 1)

> +

> +/**

> + * UACCE Device Attributes:

> + *

> + * SHARE_DOMAIN: no PASID, can shae sva only for one process and the kernel

> + * PASID: the device has IOMMU which support PASID setting

> + *	  can do share sva, mapped to dev per process

> + * FAULT_FROM_DEV: the device has IOMMU which can do page fault request

> + *		   no need for share sva, should be used with PASID

> + * SVA: full function device

> + */

> +

> +enum {

> +	UACCE_DEV_SHARE_DOMAIN = 0x0,

> +	UACCE_DEV_PASID = 0x1,

> +	UACCE_DEV_FAULT_FROM_DEV = 0x2,

> +	UACCE_DEV_SVA = UACCE_DEV_PASID | UACCE_DEV_FAULT_FROM_DEV,

> +};

> +

> +#define UACCE_QFR_NA ((unsigned long)-1)

> +

> +enum uacce_qfrt {

> +	UACCE_QFRT_MMIO = 0,	/* device mmio region */

> +	UACCE_QFRT_DKO = 1,	/* device kernel-only */

> +	UACCE_QFRT_DUS = 2,	/* device user share */

> +	UACCE_QFRT_SS = 3,	/* static share memory */

> +	UACCE_QFRT_MAX,


You should set this value too, and probably to a big number, otherwise
you just created an api that can never add a value of '4' to its list.

Why is this UACCE_QFRT_MAX even needed?

thanks,

greg k-h
zhangfei Sept. 12, 2019, 2:06 p.m. | #3
Hi, Greg

Thanks for the careful review.

On 2019/9/4 下午8:50, Greg Kroah-Hartman wrote:
> On Tue, Sep 03, 2019 at 12:14:47PM +0800, Zhangfei Gao wrote:

>> +/**

>> + * uacce_wake_up - Wake up the process who is waiting this queue

>> + * @q the accelerator queue to wake up

>> + */

>> +void uacce_wake_up(struct uacce_queue *q)

>> +{

>> +	wake_up_interruptible(&q->wait);

>> +}

>> +EXPORT_SYMBOL_GPL(uacce_wake_up);

> You are exporting things that have no in-kernel user, which is not

> allowed.

>

> Can you redo this patch series with an actual user of this new api you

> are creating?  Otherwise we have no way of properly understanding just

> what is going on here.

>

> Also, do you really need a function to do the above?  Why?

This function is used by other driver to notify the poll_wait can be 
started, like when data in fifo is ready.
I think we can directly use wake_up_interruptible(&q->wait), then the 
exporting is not required.
>> +static int uacce_dev_open_check(struct uacce_device *uacce)

>> +{

>> +	/*

>> +	 * The device can be opened once if it dose not support pasid

>> +	 */

>> +	if (uacce->flags & UACCE_DEV_PASID)

>> +		return 0;

>> +

>> +	if (atomic_cmpxchg(&uacce->state, UACCE_ST_INIT, UACCE_ST_OPENED) !=

>> +	    UACCE_ST_INIT) {

>> +		dev_info(&uacce->dev, "this device can be openned only once\n");

> No, NEVER do this, it's wrong, an easy way to spam the syslog for no

> good reason, and flat out does not work at all.

>

> Just let userspace deal with something like this, if they want to open

> multiple times, let it deal with the fallout.  Just like a tty device

> node.

Yes, understand now, this print can be triggered by user space.
>

>> +		return -EBUSY;

>> +	}

>> +

>> +	return 0;

>> +}

>> +

>> +static int uacce_fops_open(struct inode *inode, struct file *filep)

>> +{

>> +	struct uacce_queue *q;

>> +	struct iommu_sva *handle = NULL;

>> +	struct uacce_device *uacce;

>> +	int ret;

>> +	int pasid = 0;

>> +

>> +	uacce = idr_find(&uacce_idr, iminor(inode));

>> +	if (!uacce)

>> +		return -ENODEV;

>> +

>> +	if (atomic_read(&uacce->state) == UACCE_ST_RST)

>> +		return -EINVAL;

> What happens if the state changes _right_ after this check?

>

>> +

>> +	if ((!uacce->ops->get_queue) || (!uacce->ops->start_queue))

>> +		return -EINVAL;

> How would these two functions ever not be NULL?

>

> Why check for them in open()?  Why not when you register the operations?

OK, make sense.
>

>> +	if (!try_module_get(uacce->pdev->driver->owner))

>> +		return -ENODEV;

>> +

>> +	ret = uacce_dev_open_check(uacce);

>> +	if (ret)

>> +		goto open_err;

>> +

>> +#ifdef CONFIG_IOMMU_SVA

>> +	if (uacce->flags & UACCE_DEV_PASID) {

>> +		handle = iommu_sva_bind_device(uacce->pdev, current->mm, NULL);

>> +		if (IS_ERR(handle))

>> +			goto open_err;

>> +		pasid = iommu_sva_get_pasid(handle);

>> +	}

>> +#endif

>> +	ret = uacce->ops->get_queue(uacce, pasid, &q);

>> +	if (ret < 0)

>> +		goto open_err;

>> +

>> +	q->pasid = pasid;

>> +	q->handle = handle;

>> +	q->uacce = uacce;

>> +	q->mm = current->mm;

>> +	memset(q->qfrs, 0, sizeof(q->qfrs));

>> +	INIT_LIST_HEAD(&q->list);

>> +	init_waitqueue_head(&q->wait);

>> +	filep->private_data = q;

>> +	mutex_lock(&uacce->q_lock);

>> +	list_add(&q->q_dev, &uacce->qs);

>> +	mutex_unlock(&uacce->q_lock);

>> +

>> +	return 0;

>> +

>> +open_err:

>> +	module_put(uacce->pdev->driver->owner);

>> +	return ret;

>> +}

>> +

>> +static int uacce_fops_release(struct inode *inode, struct file *filep)

>> +{

>> +	struct uacce_queue *q = filep->private_data;

>> +	struct uacce_qfile_region *qfr;

>> +	struct uacce_device *uacce = q->uacce;

>> +	bool is_to_free_region;

>> +	int free_pages = 0;

>> +	int i;

>> +

>> +	mutex_lock(&uacce->q_lock);

>> +	list_del(&q->q_dev);

>> +	mutex_unlock(&uacce->q_lock);

>> +

>> +	if (atomic_read(&uacce->state) == UACCE_ST_STARTED &&

>> +	    uacce->ops->stop_queue)

>> +		uacce->ops->stop_queue(q);

> Same question as before, what happens right after this check?

>

> Do not use an atomic value thinking it is how to properly test for state

> changes.  Use a "real" lock for this, otherwise it does not work at all.

Will change this atomic, thanks
>> +

>> +	mutex_lock(&uacce_mutex);

>> +

>> +	for (i = 0; i < UACCE_QFRT_MAX; i++) {

>> +		qfr = q->qfrs[i];

>> +		if (!qfr)

>> +			continue;

>> +

>> +		is_to_free_region = false;

>> +		uacce_queue_unmap_qfr(q, qfr);

>> +		if (i == UACCE_QFRT_SS) {

>> +			list_del(&q->list);

>> +			if (list_empty(&qfr->qs))

>> +				is_to_free_region = true;

>> +		} else

>> +			is_to_free_region = true;

>> +

>> +		if (is_to_free_region) {

>> +			free_pages += qfr->nr_pages;

>> +			uacce_destroy_region(q, qfr);

>> +		}

>> +

>> +		qfr = NULL;

>> +	}

>> +

>> +	mutex_unlock(&uacce_mutex);

>> +

>> +	if (current->mm == q->mm) {

>> +		down_write(&q->mm->mmap_sem);

>> +		q->mm->data_vm -= free_pages;

>> +		up_write(&q->mm->mmap_sem);

>> +	}

>> +

>> +#ifdef CONFIG_IOMMU_SVA

>> +	if (uacce->flags & UACCE_DEV_PASID)

>> +		iommu_sva_unbind_device(q->handle);

>> +#endif

>> +

>> +	if (uacce->ops->put_queue)

>> +		uacce->ops->put_queue(q);

>> +

>> +	atomic_set(&uacce->state, UACCE_ST_INIT);

>> +	module_put(uacce->pdev->driver->owner);

>> +

>> +	return 0;

>> +}

>> +

>> +static enum uacce_qfrt uacce_get_region_type(struct uacce_device *uacce,

>> +					     struct vm_area_struct *vma)

>> +{

>> +	enum uacce_qfrt type = UACCE_QFRT_MAX;

>> +	size_t next_start = UACCE_QFR_NA;

>> +	int i;

>> +

>> +	for (i = UACCE_QFRT_MAX - 1; i >= 0; i--) {

>> +		if (vma->vm_pgoff >= uacce->qf_pg_start[i]) {

>> +			type = i;

>> +			break;

>> +		}

>> +	}

>> +

>> +	switch (type) {

>> +	case UACCE_QFRT_MMIO:

>> +		if (!uacce->ops->mmap) {

>> +			dev_err(&uacce->dev, "no driver mmap!\n");

>> +			return UACCE_QFRT_MAX;

> You not return an error?

>

>> +		}

>> +		break;

>> +

>> +	case UACCE_QFRT_DKO:

>> +		if (uacce->flags & UACCE_DEV_PASID)

>> +			return UACCE_QFRT_MAX;

> Same here, no error?

>

>> +		break;

>> +

>> +	case UACCE_QFRT_DUS:

>> +		break;

>> +

>> +	case UACCE_QFRT_SS:

>> +		/* todo: this can be valid to protect the process space */

>> +		if (uacce->flags & UACCE_DEV_FAULT_FROM_DEV)

>> +			return UACCE_QFRT_MAX;

> error?

>

>> +		break;

>> +

>> +	default:

>> +		dev_err(&uacce->dev, "uacce bug (%d)!\n", type);

> Are you now allowing userspace to spam the kernel log if you send it

> random crud?

Yes, understand, will remove this,
The print can be triggered from user space
>

>> +		return UACCE_QFRT_MAX;

> Return a proper error here and lots of other places.

OK.
>

>> +	}

>> +

>> +	/* make sure the mapping size is exactly the same as the region */

>> +	if (type < UACCE_QFRT_SS) {

>> +		for (i = type + 1; i < UACCE_QFRT_MAX; i++)

>> +			if (uacce->qf_pg_start[i] != UACCE_QFR_NA) {

>> +				next_start = uacce->qf_pg_start[i];

>> +				break;

>> +			}

>> +

>> +		if (next_start == UACCE_QFR_NA) {

>> +			dev_err(&uacce->dev, "uacce config error: SS offset set improperly\n");

>> +			return UACCE_QFRT_MAX;

>> +		}

>> +

>> +		if (vma_pages(vma) !=

>> +		    next_start - uacce->qf_pg_start[type]) {

>> +			dev_err(&uacce->dev, "invalid mmap size (%ld vs %ld pages) for region %s.\n",

>> +				vma_pages(vma),

>> +				next_start - uacce->qf_pg_start[type],

>> +				qfrt_str[type]);

>> +			return UACCE_QFRT_MAX;

>> +		}

>> +	}

>> +

>> +	return type;

>> +}

>> +

>> +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;

>> +	enum uacce_qfrt type = uacce_get_region_type(uacce, vma);

>> +	struct uacce_qfile_region *qfr;

>> +	unsigned int flags = 0;

>> +	int ret;

>> +

>> +	if (type == UACCE_QFRT_MAX)

>> +		return -EINVAL;

>> +

>> +	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;

>> +

>> +	mutex_lock(&uacce_mutex);

>> +

>> +	/* fixme: if the region need no pages, we don't need to check it */

>> +	if (q->mm->data_vm + vma_pages(vma) >

>> +	    rlimit(RLIMIT_DATA) >> PAGE_SHIFT) {

>> +		ret = -ENOMEM;

>> +		goto out_with_lock;

>> +	}

>> +

>> +	if (q->qfrs[type]) {

>> +		ret = -EBUSY;

>> +		goto out_with_lock;

>> +	}

>> +

>> +	switch (type) {

>> +	case UACCE_QFRT_MMIO:

>> +		flags = UACCE_QFRF_SELFMT;

>> +		break;

>> +

>> +	case UACCE_QFRT_SS:

>> +		if (atomic_read(&uacce->state) != UACCE_ST_STARTED) {

>> +			ret = -EINVAL;

>> +			goto out_with_lock;

>> +		}

>> +

>> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;

>> +

>> +		break;

>> +

>> +	case UACCE_QFRT_DKO:

>> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_KMAP;

>> +

>> +		break;

>> +

>> +	case UACCE_QFRT_DUS:

>> +		if (uacce->flags & UACCE_DEV_PASID) {

>> +			flags = UACCE_QFRF_SELFMT;

>> +			break;

>> +		}

>> +

>> +		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;

>> +		break;

>> +

>> +	default:

>> +		WARN_ON(&uacce->dev);

>> +		break;

>> +	}

>> +

>> +	qfr = uacce_create_region(q, vma, type, flags);

>> +	if (IS_ERR(qfr)) {

>> +		ret = PTR_ERR(qfr);

>> +		goto out_with_lock;

>> +	}

>> +	q->qfrs[type] = qfr;

>> +

>> +	if (type == UACCE_QFRT_SS) {

>> +		INIT_LIST_HEAD(&qfr->qs);

>> +		list_add(&q->list, &q->qfrs[type]->qs);

>> +	}

>> +

>> +	mutex_unlock(&uacce_mutex);

>> +

>> +	if (qfr->pages)

>> +		q->mm->data_vm += qfr->nr_pages;

>> +

>> +	return 0;

>> +

>> +out_with_lock:

>> +	mutex_unlock(&uacce_mutex);

>> +	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 UACCE_FROM_CDEV_ATTR(dev) container_of(dev, struct uacce_device, dev)

>> +

>> +static ssize_t id_show(struct device *dev,

>> +		       struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

> FROM_CDEV?  But that's not a cdev.  I'm confused.  Pick a better name

> for your macro please.

Will use to_uacce_device instead.
#define to_uacce_device(dev) container_of(dev, struct uacce_device, dev)
>

>> +

>> +	return sprintf(buf, "%d\n", uacce->dev_id);

>> +}

>> +

>> +static ssize_t api_show(struct device *dev,

>> +			struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +

>> +	return sprintf(buf, "%s\n", uacce->api_ver);

>> +}

>> +

>> +static ssize_t numa_distance_show(struct device *dev,

>> +				  struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +	int distance;

>> +

>> +	distance = node_distance(smp_processor_id(), uacce->pdev->numa_node);

>> +

>> +	return sprintf(buf, "%d\n", abs(distance));

>> +}

>> +

>> +static ssize_t node_id_show(struct device *dev,

>> +			    struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +	int node_id;

>> +

>> +	node_id = dev_to_node(uacce->pdev);

>> +

>> +	return sprintf(buf, "%d\n", node_id);

>> +}

>> +

>> +static ssize_t flags_show(struct device *dev,

>> +			  struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +

>> +	return sprintf(buf, "%d\n", uacce->flags);

>> +}

>> +

>> +static ssize_t available_instances_show(struct device *dev,

>> +					struct device_attribute *attr,

>> +					char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +	int val = 0;

>> +

>> +	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 = UACCE_FROM_CDEV_ATTR(dev);

>> +

>> +	return sprintf(buf, "%s", uacce->algs);

>> +}

>> +

>> +static ssize_t qfrs_offset_show(struct device *dev,

>> +				struct device_attribute *attr, char *buf)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +	int i, ret;

>> +	unsigned long offset;

>> +

>> +	for (i = 0, ret = 0; i < UACCE_QFRT_MAX; i++) {

>> +		offset = uacce->qf_pg_start[i];

>> +		if (offset != UACCE_QFR_NA)

>> +			offset = offset << PAGE_SHIFT;

>> +		if (i == UACCE_QFRT_SS)

>> +			break;

>> +		ret += sprintf(buf + ret, "%lu\t", offset);

>> +	}

>> +	ret += sprintf(buf + ret, "%lu\n", offset);

>> +

>> +	return ret;

>> +}

>> +

>> +static DEVICE_ATTR_RO(id);

>> +static DEVICE_ATTR_RO(api);

>> +static DEVICE_ATTR_RO(numa_distance);

>> +static DEVICE_ATTR_RO(node_id);

>> +static DEVICE_ATTR_RO(flags);

>> +static DEVICE_ATTR_RO(available_instances);

>> +static DEVICE_ATTR_RO(algorithms);

>> +static DEVICE_ATTR_RO(qfrs_offset);

>> +

>> +static struct attribute *uacce_dev_attrs[] = {

>> +	&dev_attr_id.attr,

>> +	&dev_attr_api.attr,

>> +	&dev_attr_node_id.attr,

>> +	&dev_attr_numa_distance.attr,

>> +	&dev_attr_flags.attr,

>> +	&dev_attr_available_instances.attr,

>> +	&dev_attr_algorithms.attr,

>> +	&dev_attr_qfrs_offset.attr,

>> +	NULL,

>> +};

>> +

>> +static const struct attribute_group uacce_dev_attr_group = {

>> +	.attrs	= uacce_dev_attrs,

>> +};

>> +

>> +static const struct attribute_group *uacce_dev_attr_groups[] = {

>> +	&uacce_dev_attr_group,

>> +	NULL

>> +};

> ATTRIBUTE_GROUPS()?

Yes, good idea.
>

>> +

>> +static void uacce_release(struct device *dev)

>> +{

>> +	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);

>> +

>> +	idr_remove(&uacce_idr, uacce->dev_id);

>> +	kfree(uacce);

>> +}

>> +

>> +static int uacce_create_chrdev(struct uacce_device *uacce)

> You do more than just that here, you should rename the function.

OK
>

>> +{

>> +	int ret;

>> +

>> +	ret = idr_alloc(&uacce_idr, uacce, 0, 0, GFP_KERNEL);

>> +	if (ret < 0)

>> +		return ret;

>> +

>> +	uacce->cdev = cdev_alloc();

>> +	uacce->cdev->ops = &uacce_fops;

>> +	uacce->dev_id = ret;

>> +	uacce->cdev->owner = THIS_MODULE;

>> +	device_initialize(&uacce->dev);

>> +	uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);

>> +	uacce->dev.class = uacce_class;

>> +	uacce->dev.groups = uacce_dev_attr_groups;

>> +	uacce->dev.parent = uacce->pdev;

>> +	uacce->dev.release = uacce_release;

>> +	dev_set_name(&uacce->dev, "%s-%d", uacce->drv_name, uacce->dev_id);

>> +	ret = cdev_device_add(uacce->cdev, &uacce->dev);

>> +	if (ret)

>> +		goto err_with_idr;

>> +

>> +	dev_dbg(&uacce->dev, "create uacce minior=%d\n", uacce->dev_id);

>> +

>> +	return 0;

>> +

>> +err_with_idr:

>> +	idr_remove(&uacce_idr, uacce->dev_id);

>> +	return ret;

>> +}

>> +

>> +static void uacce_destroy_chrdev(struct uacce_device *uacce)

>> +{

>> +	cdev_device_del(uacce->cdev, &uacce->dev);

>> +	put_device(&uacce->dev);

> Again, drop the _chrdev in the function name.

OK.
>> +}

>> +

>> +static int uacce_dev_match(struct device *dev, void *data)

>> +{

>> +	if (dev->parent == data)

>> +		return -EBUSY;

>> +

>> +	return 0;

> Do you really need this?

This is preventing multi uacce_register from the same dev, which is not 
supported in non sva case now.
Though we do not have such case now: same device have different 
algorithm and do multi-register.
I think we can remove this, since we have no such case now.
>> +}

>> +

>> +/* Borrowed from VFIO to fix msi translation */

>> +static bool uacce_iommu_has_sw_msi(struct iommu_group *group,

>> +				   phys_addr_t *base)

>> +{

>> +	struct list_head group_resv_regions;

>> +	struct iommu_resv_region *region, *next;

>> +	bool ret = false;

>> +

>> +	INIT_LIST_HEAD(&group_resv_regions);

>> +	iommu_get_group_resv_regions(group, &group_resv_regions);

>> +	list_for_each_entry(region, &group_resv_regions, list) {

>> +		pr_debug("uacce: find a resv region (%d) on %llx\n",

>> +			 region->type, region->start);

>> +

>> +		/*

>> +		 * The presence of any 'real' MSI regions should take

>> +		 * precedence over the software-managed one if the

>> +		 * IOMMU driver happens to advertise both types.

>> +		 */

>> +		if (region->type == IOMMU_RESV_MSI) {

>> +			ret = false;

>> +			break;

>> +		}

>> +

>> +		if (region->type == IOMMU_RESV_SW_MSI) {

>> +			*base = region->start;

>> +			ret = true;

>> +		}

>> +	}

>> +	list_for_each_entry_safe(region, next, &group_resv_regions, list)

>> +		kfree(region);

>> +

>> +	return ret;

>> +}

>> +

>> +static int uacce_set_iommu_domain(struct uacce_device *uacce)

>> +{

>> +	struct iommu_domain *domain;

>> +	struct iommu_group *group;

>> +	struct device *dev = uacce->pdev;

>> +	bool resv_msi;

>> +	phys_addr_t resv_msi_base = 0;

>> +	int ret;

>> +

>> +	if (uacce->flags & UACCE_DEV_PASID)

>> +		return 0;

>> +

>> +	/*

>> +	 * We don't support multiple register for the same dev if no pasid

>> +	 */

>> +	ret = class_for_each_device(uacce_class, NULL, uacce->pdev,

>> +				    uacce_dev_match);

>> +	if (ret)

>> +		return ret;

>> +

>> +	/* allocate and attach a unmanged domain */

>> +	domain = iommu_domain_alloc(uacce->pdev->bus);

>> +	if (!domain) {

>> +		dev_err(&uacce->dev, "cannot get domain for iommu\n");

>> +		return -ENODEV;

>> +	}

>> +

>> +	ret = iommu_attach_device(domain, uacce->pdev);

>> +	if (ret)

>> +		goto err_with_domain;

>> +

>> +	if (iommu_capable(dev->bus, IOMMU_CAP_CACHE_COHERENCY))

>> +		uacce->prot |= IOMMU_CACHE;

>> +

>> +	group = iommu_group_get(dev);

>> +	if (!group) {

>> +		ret = -EINVAL;

>> +		goto err_with_domain;

>> +	}

>> +

>> +	resv_msi = uacce_iommu_has_sw_msi(group, &resv_msi_base);

>> +	iommu_group_put(group);

>> +

>> +	if (resv_msi) {

>> +		if (!irq_domain_check_msi_remap() &&

>> +		    !iommu_capable(dev->bus, IOMMU_CAP_INTR_REMAP)) {

>> +			dev_warn(dev, "No interrupt remapping support!");

>> +			ret = -EPERM;

>> +			goto err_with_domain;

>> +		}

>> +

>> +		ret = iommu_get_msi_cookie(domain, resv_msi_base);

>> +		if (ret)

>> +			goto err_with_domain;

>> +	}

>> +

>> +	return 0;

>> +

>> +err_with_domain:

>> +	iommu_domain_free(domain);

>> +	return ret;

>> +}

>> +

>> +static void uacce_unset_iommu_domain(struct uacce_device *uacce)

>> +{

>> +	struct iommu_domain *domain;

>> +

>> +	if (uacce->flags & UACCE_DEV_PASID)

>> +		return;

>> +

>> +	domain = iommu_get_domain_for_dev(uacce->pdev);

>> +	if (!domain) {

>> +		dev_err(&uacce->dev, "bug: no domain attached to device\n");

>> +		return;

>> +	}

>> +

>> +	iommu_detach_device(domain, uacce->pdev);

>> +	iommu_domain_free(domain);

>> +}

>> +

>> +/**

>> + *	uacce_register - register an accelerator

>> + *	@uacce: the accelerator structure

>> + */

>> +struct uacce_device *uacce_register(struct device *parent,

>> +				    struct uacce_interface *interface)

>> +{

>> +	int ret, i;

>> +	struct uacce_device *uacce;

>> +	unsigned int flags = interface->flags;

>> +

>> +	/* if dev support fault-from-dev, it should support pasid */

>> +	if ((flags & UACCE_DEV_FAULT_FROM_DEV) && !(flags & UACCE_DEV_PASID)) {

>> +		dev_warn(parent, "SVM/SAV device should support PASID\n");

>> +		return ERR_PTR(-EINVAL);

>> +	}

>> +

>> +#ifdef CONFIG_IOMMU_SVA

>> +	if (flags & UACCE_DEV_PASID) {

>> +		ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);

>> +		if (ret)

>> +			flags &= ~(UACCE_DEV_FAULT_FROM_DEV |

>> +				   UACCE_DEV_PASID);

>> +	}

>> +#endif

>> +	uacce = kzalloc(sizeof(struct uacce_device), GFP_KERNEL);

>> +	if (!uacce)

>> +		return ERR_PTR(-ENOMEM);

>> +

>> +	uacce->pdev = parent;

>> +	uacce->flags = flags;

>> +	uacce->ops = interface->ops;

>> +	uacce->drv_name = interface->name;

>> +

>> +	for (i = 0; i < UACCE_QFRT_MAX; i++)

>> +		uacce->qf_pg_start[i] = UACCE_QFR_NA;

>> +

>> +	ret = uacce_set_iommu_domain(uacce);

>> +	if (ret)

>> +		goto err_free;

>> +

>> +	mutex_lock(&uacce_mutex);

>> +

>> +	ret = uacce_create_chrdev(uacce);

>> +	if (ret)

>> +		goto err_with_lock;

>> +

>> +	atomic_set(&uacce->state, UACCE_ST_INIT);

>> +	INIT_LIST_HEAD(&uacce->qs);

>> +	mutex_init(&uacce->q_lock);

>> +

>> +	mutex_unlock(&uacce_mutex);

>> +

>> +	return uacce;

>> +

>> +err_with_lock:

>> +	mutex_unlock(&uacce_mutex);

>> +err_free:

>> +	kfree(uacce);

>> +	return ERR_PTR(ret);

>> +}

>> +EXPORT_SYMBOL_GPL(uacce_register);

>> +

>> +/**

>> + * uacce_unregister - unregisters a uacce

>> + * @uacce: the accelerator to unregister

>> + *

>> + * Unregister an accelerator that wat previously successully registered with

>> + * uacce_register().

>> + */

>> +void uacce_unregister(struct uacce_device *uacce)

>> +{

>> +	mutex_lock(&uacce_mutex);

>> +

>> +#ifdef CONFIG_IOMMU_SVA

>> +	if (uacce->flags & UACCE_DEV_PASID)

>> +		iommu_dev_disable_feature(uacce->pdev, IOMMU_DEV_FEAT_SVA);

>> +#endif

>> +	uacce_unset_iommu_domain(uacce);

>> +	uacce_destroy_chrdev(uacce);

>> +

>> +	mutex_unlock(&uacce_mutex);

>> +}

>> +EXPORT_SYMBOL_GPL(uacce_unregister);

>> +

>> +static int __init uacce_init(void)

>> +{

>> +	int ret;

>> +

>> +	uacce_class = class_create(THIS_MODULE, UACCE_NAME);

>> +	if (IS_ERR(uacce_class)) {

>> +		ret = PTR_ERR(uacce_class);

>> +		goto err;

>> +	}

>> +

>> +	ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);

>> +	if (ret)

>> +		goto err_with_class;

>> +

>> +	pr_info("uacce init with major number:%d\n", MAJOR(uacce_devt));

> When your code works properly, it is totally silent.  Do not spam the

> kernel log for no good reason.  Stuff like this is debugging only, if

> that as you can see it in the proper /proc/ file.

OK, understand.
>

>> +

>> +	return 0;

>> +

>> +err_with_class:

>> +	class_destroy(uacce_class);

>> +err:

>> +	return ret;

>> +}

>> +

>> +static __exit void uacce_exit(void)

>> +{

>> +	unregister_chrdev_region(uacce_devt, MINORMASK);

>> +	class_destroy(uacce_class);

>> +	idr_destroy(&uacce_idr);

>> +}

>> +

>> +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..b23a28b

>> --- /dev/null

>> +++ b/include/linux/uacce.h

>> @@ -0,0 +1,172 @@

>> +/* SPDX-License-Identifier: GPL-2.0-or-later */

>> +#ifndef __UACCE_H

>> +#define __UACCE_H

>> +

>> +#include <linux/cdev.h>

>> +#include <linux/device.h>

>> +#include <linux/fs.h>

>> +#include <linux/list.h>

>> +#include <linux/iommu.h>

>> +#include <uapi/misc/uacce.h>

> Why are all of these needed in this .h file?  Are you sure?

Sorry, only two of them are required.
>

>> +

>> +#define UACCE_NAME		"uacce"

>> +

>> +struct uacce_queue;

>> +struct uacce_device;

>> +

>> +/* uacce mode of the driver */

>> +#define UACCE_MODE_NOUACCE	0 /* don't use uacce */

>> +#define UACCE_MODE_UACCE	1 /* use uacce exclusively */

>> +

>> +/* uacce queue file flag, requires different operation */

>> +#define UACCE_QFRF_MAP		BIT(0)	/* map to current queue */

>> +#define UACCE_QFRF_MMAP		BIT(1)	/* map to user space */

>> +#define UACCE_QFRF_KMAP		BIT(2)	/* map to kernel space */

>> +#define UACCE_QFRF_DMA		BIT(3)	/* use dma api for the region */

>> +#define UACCE_QFRF_SELFMT	BIT(4)	/* self maintained qfr */

>> +

>> +/**

>> + * struct uacce_qfile_region - structure of queue file region

>> + * @type: type of the qfr

>> + * @iova: iova share between user and device space

>> + * @pages: pages pointer of the qfr memory

>> + * @nr_pages: page numbers of the qfr memory

>> + * @prot: qfr protection flag

>> + * @flags: flags of qfr

>> + * @qs: list sharing the same region, for ss region

>> + * @kaddr: kernel addr of the qfr

>> + * @dma: dma address, if created by dma api

>> + */

>> +struct uacce_qfile_region {

>> +	enum uacce_qfrt type;

>> +	unsigned long iova;

>> +	struct page **pages;

>> +	int nr_pages;

>> +	int prot;

>> +	unsigned int flags;

>> +	struct list_head qs;

>> +	void *kaddr;

>> +	dma_addr_t dma;

>> +};

>> +

>> +/**

>> + * 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

>> + * @mask_notify: mask the task irq of queue

>> + * @mmap: mmap addresses of queue to user space

>> + * @reset: reset the uacce device

>> + * @reset_queue: reset the queue

>> + * @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);

>> +	void (*mask_notify)(struct uacce_queue *q, int event_mask);

>> +	int (*mmap)(struct uacce_queue *q, struct vm_area_struct *vma,

>> +		    struct uacce_qfile_region *qfr);

>> +	int (*reset)(struct uacce_device *uacce);

>> +	int (*reset_queue)(struct uacce_queue *q);

>> +	long (*ioctl)(struct uacce_queue *q, unsigned int cmd,

>> +		      unsigned long arg);

>> +};

>> +

>> +/**

>> + * struct uacce_interface

>> + * @name: the uacce device name.  Will show up in sysfs

>> + * @flags: uacce device attributes

>> + * @ops: pointer to the struct uacce_ops

>> + *

>> + * This structure is used for the uacce_register()

>> + */

>> +struct uacce_interface {

>> +	char name[32];

>> +	unsigned int flags;

>> +	struct uacce_ops *ops;

>> +};

>> +

>> +/**

>> + * struct uacce_queue

>> + * @uacce: pointer to uacce

>> + * @priv: private pointer

>> + * @wait: wait queue head

>> + * @pasid: pasid of the queue

>> + * @handle: iommu_sva handle return from iommu_sva_bind_device

>> + * @list: share list for qfr->qs

>> + * @mm: current->mm

>> + * @qfrs: pointer of qfr regions

>> + * @q_dev: list for uacce->qs

>> + */

>> +struct uacce_queue {

>> +	struct uacce_device *uacce;

>> +	void *priv;

>> +	wait_queue_head_t wait;

>> +	int pasid;

>> +	struct iommu_sva *handle;

>> +	struct list_head list;

>> +	struct mm_struct *mm;

>> +	struct uacce_qfile_region *qfrs[UACCE_QFRT_MAX];

>> +	struct list_head q_dev;

>> +};

>> +

>> +/* uacce state */

>> +enum {

>> +	UACCE_ST_INIT = 0,

>> +	UACCE_ST_OPENED,

>> +	UACCE_ST_STARTED,

>> +	UACCE_ST_RST,

>> +};

>> +

>> +/**

>> + * struct uacce_device

>> + * @drv_name: the uacce driver name.  Will show up in sysfs

>> + * @algs: supported algorithms

>> + * @api_ver: api version

>> + * @flags: uacce attributes

>> + * @qf_pg_start: page start of the queue file regions

>> + * @ops: pointer to the struct uacce_ops

>> + * @pdev: pointer to the parent device

>> + * @is_vf: whether virtual function

>> + * @dev_id: id of the uacce device

>> + * @cdev: cdev of the uacce

>> + * @dev: dev of the uacce

>> + * @priv: private pointer of the uacce

>> + * @state: uacce state

>> + * @prot: uacce protection flag

>> + * @q_lock: uacce mutex lock for queue

>> + * @qs: uacce list head for share

>> + */

>> +struct uacce_device {

>> +	const char *drv_name;

> A driver is bound to a device, and you can get the name there.  No need

> for it to be here.

>

>> +	const char *algs;

>> +	const char *api_ver;

>> +	unsigned int flags;

> u64?

>

>> +	unsigned long qf_pg_start[UACCE_QFRT_MAX];

>> +	struct uacce_ops *ops;

>> +	struct device *pdev;

>> +	bool is_vf;

>> +	u32 dev_id;

>> +	struct cdev *cdev;

>> +	struct device dev;

>> +	void *priv;

>> +	atomic_t state;

>> +	int prot;

> u32?

OK.
>

>

>> +	struct mutex q_lock;

>> +	struct list_head qs;

> What's wrong with the list in the device itself?

Double checked, will remove this.
>

>> +};

>> +

>> +struct uacce_device *uacce_register(struct device *parent,

>> +				    struct uacce_interface *interface);

>> +void uacce_unregister(struct uacce_device *uacce);

>> +void uacce_wake_up(struct uacce_queue *q);

>> +

>> +#endif

>> diff --git a/include/uapi/misc/uacce.h b/include/uapi/misc/uacce.h

>> new file mode 100644

>> index 0000000..685b4a1

>> --- /dev/null

>> +++ b/include/uapi/misc/uacce.h

>> @@ -0,0 +1,39 @@

>> +/* SPDX-License-Identifier: GPL-2.0-or-later */

>> +#ifndef _UAPIUUACCE_H

>> +#define _UAPIUUACCE_H

>> +

>> +#include <linux/types.h>

>> +#include <linux/ioctl.h>

>> +

>> +#define UACCE_CMD_SHARE_SVAS	_IO('W', 0)

>> +#define UACCE_CMD_START		_IO('W', 1)

>> +

>> +/**

>> + * UACCE Device Attributes:

>> + *

>> + * SHARE_DOMAIN: no PASID, can shae sva only for one process and the kernel

>> + * PASID: the device has IOMMU which support PASID setting

>> + *	  can do share sva, mapped to dev per process

>> + * FAULT_FROM_DEV: the device has IOMMU which can do page fault request

>> + *		   no need for share sva, should be used with PASID

>> + * SVA: full function device

>> + */

>> +

>> +enum {

>> +	UACCE_DEV_SHARE_DOMAIN = 0x0,

>> +	UACCE_DEV_PASID = 0x1,

>> +	UACCE_DEV_FAULT_FROM_DEV = 0x2,

>> +	UACCE_DEV_SVA = UACCE_DEV_PASID | UACCE_DEV_FAULT_FROM_DEV,

>> +};

>> +

>> +#define UACCE_QFR_NA ((unsigned long)-1)

>> +

>> +enum uacce_qfrt {

>> +	UACCE_QFRT_MMIO = 0,	/* device mmio region */

>> +	UACCE_QFRT_DKO = 1,	/* device kernel-only */

>> +	UACCE_QFRT_DUS = 2,	/* device user share */

>> +	UACCE_QFRT_SS = 3,	/* static share memory */

>> +	UACCE_QFRT_MAX,

> You should set this value too, and probably to a big number, otherwise

> you just created an api that can never add a value of '4' to its list.

>

> Why is this UACCE_QFRT_MAX even needed?

>

Good idea, will use UACCE_QFRT_MAX = 16 instead.
UACCE_QFRT_MAX is required in struct uacce_device and uacce_queue.
Like struct uacce_qfile_region *qfrs[UACCE_QFRT_MAX] to record different 
region.

Thanks
zhangfei Sept. 12, 2019, 2:09 p.m. | #4
On 2019/9/4 下午8:38, Greg Kroah-Hartman wrote:
> On Tue, Sep 03, 2019 at 12:14:47PM +0800, Zhangfei Gao wrote:

>> From: Kenneth Lee <liguozhu@hisilicon.com>

>>

>> Uacce (Unified/User-space-access-intended Accelerator Framework) targets to

>> provide Shared Virtual Addressing (SVA) between accelerators and processes.

>> So accelerator can access any data structure of the main cpu.

>> This differs from the data sharing between cpu and io device, which share

>> data content rather than address.

>> Since unified address, hardware and user space of process can share the

>> same virtual address in the communication.

>>

>> Uacce create a chrdev for every registration, the queue is allocated to

>> the process when the chrdev is opened. Then the process can access the

>> hardware resource by interact with the queue file. By mmap the queue

>> file space to user space, the process can directly put requests to the

>> hardware without syscall to the kernel space.

>>

>> Signed-off-by: Kenneth Lee <liguozhu@hisilicon.com>

>> Signed-off-by: Zaibo Xu <xuzaibo@huawei.com>

>> Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>

>> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>

>> ---

>>   Documentation/ABI/testing/sysfs-driver-uacce |   47 ++

>>   drivers/misc/Kconfig                         |    1 +

>>   drivers/misc/Makefile                        |    1 +

>>   drivers/misc/uacce/Kconfig                   |   13 +

>>   drivers/misc/uacce/Makefile                  |    2 +

>>   drivers/misc/uacce/uacce.c                   | 1096 ++++++++++++++++++++++++++

>>   include/linux/uacce.h                        |  172 ++++

>>   include/uapi/misc/uacce.h                    |   39 +

>>   8 files changed, 1371 insertions(+)

>>   create mode 100644 Documentation/ABI/testing/sysfs-driver-uacce

>>   create mode 100644 drivers/misc/uacce/Kconfig

>>   create mode 100644 drivers/misc/uacce/Makefile

>>   create mode 100644 drivers/misc/uacce/uacce.c

>>   create mode 100644 include/linux/uacce.h

>>   create mode 100644 include/uapi/misc/uacce.h

>>

>> diff --git a/Documentation/ABI/testing/sysfs-driver-uacce b/Documentation/ABI/testing/sysfs-driver-uacce

>> new file mode 100644

>> index 0000000..ee0a66e

>> --- /dev/null

>> +++ b/Documentation/ABI/testing/sysfs-driver-uacce

>> @@ -0,0 +1,47 @@

>> +What:           /sys/class/uacce/hisi_zip-<n>/id

>> +Date:           Sep 2019

>> +KernelVersion:  5.3

> 5.3 will be released in a week or so, without this file in it, so that's

> not ok here :(

>

Thanks, will use 5.4 instead.
Since 5.4-rc1 still need some time, can I send updated version based on 
5.3-rc8 for more review.
And I found smmu in 5.3-rc1 have issue, and rc8 is OK.

Thanks

Patch

diff --git a/Documentation/ABI/testing/sysfs-driver-uacce b/Documentation/ABI/testing/sysfs-driver-uacce
new file mode 100644
index 0000000..ee0a66e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-uacce
@@ -0,0 +1,47 @@ 
+What:           /sys/class/uacce/hisi_zip-<n>/id
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Id of the device.
+
+What:           /sys/class/uacce/hisi_zip-<n>/api
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Api of the device, used by application to match the correct driver
+
+What:           /sys/class/uacce/hisi_zip-<n>/flags
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Attributes of the device, see UACCE_DEV_xxx flag defined in uacce.h
+
+What:           /sys/class/uacce/hisi_zip-<n>/available_instances
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Available instances left of the device
+
+What:           /sys/class/uacce/hisi_zip-<n>/algorithms
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Algorithms supported by this accelerator
+
+What:           /sys/class/uacce/hisi_zip-<n>/qfrs_offset
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Page offsets of each queue file regions
+
+What:           /sys/class/uacce/hisi_zip-<n>/numa_distance
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Distance of device node to cpu node
+
+What:           /sys/class/uacce/hisi_zip-<n>/node_id
+Date:           Sep 2019
+KernelVersion:  5.3
+Contact:        linux-accelerators@lists.ozlabs.org
+Description:    Id of the numa node
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 6abfc8e..8073eb8 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -502,4 +502,5 @@  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 abd8ae2..93a131b 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -58,4 +58,5 @@  obj-$(CONFIG_OCXL)		+= ocxl/
 obj-y				+= cardreader/
 obj-$(CONFIG_PVPANIC)   	+= pvpanic.o
 obj-$(CONFIG_HABANA_AI)		+= habanalabs/
+obj-$(CONFIG_UACCE)		+= uacce/
 obj-$(CONFIG_XILINX_SDFEC)	+= xilinx_sdfec.o
diff --git a/drivers/misc/uacce/Kconfig b/drivers/misc/uacce/Kconfig
new file mode 100644
index 0000000..e854354
--- /dev/null
+++ b/drivers/misc/uacce/Kconfig
@@ -0,0 +1,13 @@ 
+config UACCE
+	tristate "Accelerator Framework for User Land"
+	depends on IOMMU_API
+	help
+	  UACCE provides interface for the user process to access the hardware
+	  without interaction with the kernel space in data path.
+
+	  The user-space interface is described in
+	  include/uapi/misc/uacce.h
+
+	  See Documentation/misc-devices/uacce.rst for more details.
+
+	  If you don't know what to do here, say N.
diff --git a/drivers/misc/uacce/Makefile b/drivers/misc/uacce/Makefile
new file mode 100644
index 0000000..5b4374e
--- /dev/null
+++ b/drivers/misc/uacce/Makefile
@@ -0,0 +1,2 @@ 
+# SPDX-License-Identifier: GPL-2.0-or-later
+obj-$(CONFIG_UACCE) += uacce.o
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
new file mode 100644
index 0000000..344d238
--- /dev/null
+++ b/drivers/misc/uacce/uacce.c
@@ -0,0 +1,1096 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/compat.h>
+#include <linux/dma-iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/file.h>
+#include <linux/idr.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/sched/signal.h>
+#include <linux/uacce.h>
+
+static struct class *uacce_class;
+static DEFINE_IDR(uacce_idr);
+static dev_t uacce_devt;
+static DEFINE_MUTEX(uacce_mutex); /* mutex to protect uacce */
+static const struct file_operations uacce_fops;
+
+/* match with enum uacce_qfrt */
+static const char *const qfrt_str[] = {
+	"mmio",
+	"dko",
+	"dus",
+	"ss",
+	"invalid"
+};
+
+static const char *uacce_qfrt_str(struct uacce_qfile_region *qfr)
+{
+	enum uacce_qfrt type = qfr->type;
+
+	if (type > UACCE_QFRT_MAX)
+		type = UACCE_QFRT_MAX;
+
+	return qfrt_str[type];
+}
+
+/**
+ * uacce_wake_up - Wake up the process who is waiting this queue
+ * @q the accelerator queue to wake up
+ */
+void uacce_wake_up(struct uacce_queue *q)
+{
+	wake_up_interruptible(&q->wait);
+}
+EXPORT_SYMBOL_GPL(uacce_wake_up);
+
+static int uacce_queue_map_qfr(struct uacce_queue *q,
+			       struct uacce_qfile_region *qfr)
+{
+	struct device *dev = q->uacce->pdev;
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+	int i, j, ret;
+
+	if (!(qfr->flags & UACCE_QFRF_MAP) || (qfr->flags & UACCE_QFRF_DMA))
+		return 0;
+
+	if (!domain)
+		return -ENODEV;
+
+	for (i = 0; i < qfr->nr_pages; i++) {
+		ret = iommu_map(domain, qfr->iova + i * PAGE_SIZE,
+				page_to_phys(qfr->pages[i]),
+				PAGE_SIZE, qfr->prot | q->uacce->prot);
+		if (ret) {
+			dev_err(dev, "iommu_map page %i fail %d\n", i, ret);
+			goto err_with_map_pages;
+		}
+		get_page(qfr->pages[i]);
+	}
+
+	return 0;
+
+err_with_map_pages:
+	for (j = i - 1; j >= 0; j--) {
+		iommu_unmap(domain, qfr->iova + j * PAGE_SIZE, PAGE_SIZE);
+		put_page(qfr->pages[j]);
+	}
+	return ret;
+}
+
+static void uacce_queue_unmap_qfr(struct uacce_queue *q,
+				  struct uacce_qfile_region *qfr)
+{
+	struct device *dev = q->uacce->pdev;
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+	int i;
+
+	if (!domain || !qfr)
+		return;
+
+	if (!(qfr->flags & UACCE_QFRF_MAP) || (qfr->flags & UACCE_QFRF_DMA))
+		return;
+
+	for (i = qfr->nr_pages - 1; i >= 0; i--) {
+		iommu_unmap(domain, qfr->iova + i * PAGE_SIZE, PAGE_SIZE);
+		put_page(qfr->pages[i]);
+	}
+}
+
+static int uacce_qfr_alloc_pages(struct uacce_qfile_region *qfr)
+{
+	int i, j;
+
+	qfr->pages = kcalloc(qfr->nr_pages, sizeof(*qfr->pages), GFP_ATOMIC);
+	if (!qfr->pages)
+		return -ENOMEM;
+
+	for (i = 0; i < qfr->nr_pages; i++) {
+		qfr->pages[i] = alloc_page(GFP_ATOMIC | __GFP_ZERO);
+		if (!qfr->pages[i])
+			goto err_with_pages;
+	}
+
+	return 0;
+
+err_with_pages:
+	for (j = i - 1; j >= 0; j--)
+		put_page(qfr->pages[j]);
+
+	kfree(qfr->pages);
+	return -ENOMEM;
+}
+
+static void uacce_qfr_free_pages(struct uacce_qfile_region *qfr)
+{
+	int i;
+
+	for (i = 0; i < qfr->nr_pages; i++)
+		put_page(qfr->pages[i]);
+
+	kfree(qfr->pages);
+}
+
+static inline int uacce_queue_mmap_qfr(struct uacce_queue *q,
+				       struct uacce_qfile_region *qfr,
+				       struct vm_area_struct *vma)
+{
+	int i, ret;
+
+	for (i = 0; i < qfr->nr_pages; i++) {
+		ret = remap_pfn_range(vma, vma->vm_start + (i << PAGE_SHIFT),
+				      page_to_pfn(qfr->pages[i]), PAGE_SIZE,
+				      vma->vm_page_prot);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static struct uacce_qfile_region *
+uacce_create_region(struct uacce_queue *q, struct vm_area_struct *vma,
+		    enum uacce_qfrt type, unsigned int flags)
+{
+	struct uacce_qfile_region *qfr;
+	struct uacce_device *uacce = q->uacce;
+	unsigned long vm_pgoff;
+	int ret = -ENOMEM;
+
+	qfr = kzalloc(sizeof(*qfr), GFP_ATOMIC);
+	if (!qfr)
+		return ERR_PTR(-ENOMEM);
+
+	qfr->type = type;
+	qfr->flags = flags;
+	qfr->iova = vma->vm_start;
+	qfr->nr_pages = vma_pages(vma);
+
+	if (vma->vm_flags & VM_READ)
+		qfr->prot |= IOMMU_READ;
+
+	if (vma->vm_flags & VM_WRITE)
+		qfr->prot |= IOMMU_WRITE;
+
+	if (flags & UACCE_QFRF_SELFMT) {
+		ret = uacce->ops->mmap(q, vma, qfr);
+		if (ret)
+			goto err_with_qfr;
+		return qfr;
+	}
+
+	/* allocate memory */
+	if (flags & UACCE_QFRF_DMA) {
+		qfr->kaddr = dma_alloc_coherent(uacce->pdev,
+						qfr->nr_pages << PAGE_SHIFT,
+						&qfr->dma, GFP_KERNEL);
+		if (!qfr->kaddr) {
+			ret = -ENOMEM;
+			goto err_with_qfr;
+		}
+	} else {
+		ret = uacce_qfr_alloc_pages(qfr);
+		if (ret)
+			goto err_with_qfr;
+	}
+
+	/* map to device */
+	ret = uacce_queue_map_qfr(q, qfr);
+	if (ret)
+		goto err_with_pages;
+
+	/* mmap to user space */
+	if (flags & UACCE_QFRF_MMAP) {
+		if (flags & UACCE_QFRF_DMA) {
+			/* dma_mmap_coherent() requires vm_pgoff as 0
+			 * restore vm_pfoff to initial value for mmap()
+			 */
+			vm_pgoff = vma->vm_pgoff;
+			vma->vm_pgoff = 0;
+			ret = dma_mmap_coherent(uacce->pdev, vma, qfr->kaddr,
+						qfr->dma,
+						qfr->nr_pages << PAGE_SHIFT);
+			vma->vm_pgoff = vm_pgoff;
+		} else {
+			ret = uacce_queue_mmap_qfr(q, qfr, vma);
+		}
+
+		if (ret)
+			goto err_with_mapped_qfr;
+	}
+
+	return qfr;
+
+err_with_mapped_qfr:
+	uacce_queue_unmap_qfr(q, qfr);
+err_with_pages:
+	if (flags & UACCE_QFRF_DMA)
+		dma_free_coherent(uacce->pdev, qfr->nr_pages << PAGE_SHIFT,
+				  qfr->kaddr, qfr->dma);
+	else
+		uacce_qfr_free_pages(qfr);
+err_with_qfr:
+	kfree(qfr);
+
+	return ERR_PTR(ret);
+}
+
+static void uacce_destroy_region(struct uacce_queue *q,
+				 struct uacce_qfile_region *qfr)
+{
+	struct uacce_device *uacce = q->uacce;
+
+	if (qfr->flags & UACCE_QFRF_DMA) {
+		dma_free_coherent(uacce->pdev, qfr->nr_pages << PAGE_SHIFT,
+				  qfr->kaddr, qfr->dma);
+	} else if (qfr->pages) {
+		if (qfr->flags & UACCE_QFRF_KMAP && qfr->kaddr) {
+			vunmap(qfr->kaddr);
+			qfr->kaddr = NULL;
+		}
+
+		uacce_qfr_free_pages(qfr);
+	}
+	kfree(qfr);
+}
+
+static long uacce_cmd_share_qfr(struct uacce_queue *tgt, int fd)
+{
+	struct file *filep;
+	struct uacce_queue *src;
+	int ret = -EINVAL;
+
+	filep = fget(fd);
+	if (!filep)
+		return ret;
+
+	if (filep->f_op != &uacce_fops)
+		goto out_with_fd;
+
+	src = filep->private_data;
+	if (!src)
+		goto out_with_fd;
+
+	/* no share sva is needed if the dev can do fault-from-dev */
+	if (tgt->uacce->flags & UACCE_DEV_FAULT_FROM_DEV)
+		goto out_with_fd;
+
+	mutex_lock(&uacce_mutex);
+	if (!src->qfrs[UACCE_QFRT_SS] || tgt->qfrs[UACCE_QFRT_SS])
+		goto out_with_lock;
+
+	ret = uacce_queue_map_qfr(tgt, src->qfrs[UACCE_QFRT_SS]);
+	if (ret)
+		goto out_with_lock;
+
+	tgt->qfrs[UACCE_QFRT_SS] = src->qfrs[UACCE_QFRT_SS];
+	list_add(&tgt->list, &src->qfrs[UACCE_QFRT_SS]->qs);
+
+out_with_lock:
+	mutex_unlock(&uacce_mutex);
+out_with_fd:
+	fput(filep);
+	return ret;
+}
+
+static int uacce_start_queue(struct uacce_queue *q)
+{
+	int ret, i, j;
+	struct uacce_qfile_region *qfr;
+	struct device *dev = &q->uacce->dev;
+
+	/*
+	 * map KMAP qfr to kernel
+	 * vmap should be done in non-spinlocked context!
+	 */
+	for (i = 0; i < UACCE_QFRT_MAX; i++) {
+		qfr = q->qfrs[i];
+		if (qfr && (qfr->flags & UACCE_QFRF_KMAP) && !qfr->kaddr) {
+			qfr->kaddr = vmap(qfr->pages, qfr->nr_pages, VM_MAP,
+					  PAGE_KERNEL);
+			if (!qfr->kaddr) {
+				ret = -ENOMEM;
+				dev_err(dev, "fail to kmap %s qfr(%d pages)\n",
+					uacce_qfrt_str(qfr), qfr->nr_pages);
+				goto err_with_vmap;
+			}
+		}
+	}
+
+	ret = q->uacce->ops->start_queue(q);
+	if (ret < 0)
+		goto err_with_vmap;
+
+	atomic_set(&q->uacce->state, UACCE_ST_STARTED);
+
+	return 0;
+
+err_with_vmap:
+	for (j = i; j >= 0; j--) {
+		qfr = q->qfrs[j];
+		if (qfr && qfr->kaddr) {
+			vunmap(qfr->kaddr);
+			qfr->kaddr = NULL;
+		}
+	}
+	return ret;
+}
+
+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_SHARE_SVAS:
+		return uacce_cmd_share_qfr(q, arg);
+
+	case UACCE_CMD_START:
+		return uacce_start_queue(q);
+
+	default:
+		if (!uacce->ops->ioctl) {
+			dev_err(&uacce->dev,
+				"ioctl cmd (%d) is not supported!\n", cmd);
+			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_dev_open_check(struct uacce_device *uacce)
+{
+	/*
+	 * The device can be opened once if it dose not support pasid
+	 */
+	if (uacce->flags & UACCE_DEV_PASID)
+		return 0;
+
+	if (atomic_cmpxchg(&uacce->state, UACCE_ST_INIT, UACCE_ST_OPENED) !=
+	    UACCE_ST_INIT) {
+		dev_info(&uacce->dev, "this device can be openned only once\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int uacce_fops_open(struct inode *inode, struct file *filep)
+{
+	struct uacce_queue *q;
+	struct iommu_sva *handle = NULL;
+	struct uacce_device *uacce;
+	int ret;
+	int pasid = 0;
+
+	uacce = idr_find(&uacce_idr, iminor(inode));
+	if (!uacce)
+		return -ENODEV;
+
+	if (atomic_read(&uacce->state) == UACCE_ST_RST)
+		return -EINVAL;
+
+	if ((!uacce->ops->get_queue) || (!uacce->ops->start_queue))
+		return -EINVAL;
+
+	if (!try_module_get(uacce->pdev->driver->owner))
+		return -ENODEV;
+
+	ret = uacce_dev_open_check(uacce);
+	if (ret)
+		goto open_err;
+
+#ifdef CONFIG_IOMMU_SVA
+	if (uacce->flags & UACCE_DEV_PASID) {
+		handle = iommu_sva_bind_device(uacce->pdev, current->mm, NULL);
+		if (IS_ERR(handle))
+			goto open_err;
+		pasid = iommu_sva_get_pasid(handle);
+	}
+#endif
+	ret = uacce->ops->get_queue(uacce, pasid, &q);
+	if (ret < 0)
+		goto open_err;
+
+	q->pasid = pasid;
+	q->handle = handle;
+	q->uacce = uacce;
+	q->mm = current->mm;
+	memset(q->qfrs, 0, sizeof(q->qfrs));
+	INIT_LIST_HEAD(&q->list);
+	init_waitqueue_head(&q->wait);
+	filep->private_data = q;
+	mutex_lock(&uacce->q_lock);
+	list_add(&q->q_dev, &uacce->qs);
+	mutex_unlock(&uacce->q_lock);
+
+	return 0;
+
+open_err:
+	module_put(uacce->pdev->driver->owner);
+	return ret;
+}
+
+static int uacce_fops_release(struct inode *inode, struct file *filep)
+{
+	struct uacce_queue *q = filep->private_data;
+	struct uacce_qfile_region *qfr;
+	struct uacce_device *uacce = q->uacce;
+	bool is_to_free_region;
+	int free_pages = 0;
+	int i;
+
+	mutex_lock(&uacce->q_lock);
+	list_del(&q->q_dev);
+	mutex_unlock(&uacce->q_lock);
+
+	if (atomic_read(&uacce->state) == UACCE_ST_STARTED &&
+	    uacce->ops->stop_queue)
+		uacce->ops->stop_queue(q);
+
+	mutex_lock(&uacce_mutex);
+
+	for (i = 0; i < UACCE_QFRT_MAX; i++) {
+		qfr = q->qfrs[i];
+		if (!qfr)
+			continue;
+
+		is_to_free_region = false;
+		uacce_queue_unmap_qfr(q, qfr);
+		if (i == UACCE_QFRT_SS) {
+			list_del(&q->list);
+			if (list_empty(&qfr->qs))
+				is_to_free_region = true;
+		} else
+			is_to_free_region = true;
+
+		if (is_to_free_region) {
+			free_pages += qfr->nr_pages;
+			uacce_destroy_region(q, qfr);
+		}
+
+		qfr = NULL;
+	}
+
+	mutex_unlock(&uacce_mutex);
+
+	if (current->mm == q->mm) {
+		down_write(&q->mm->mmap_sem);
+		q->mm->data_vm -= free_pages;
+		up_write(&q->mm->mmap_sem);
+	}
+
+#ifdef CONFIG_IOMMU_SVA
+	if (uacce->flags & UACCE_DEV_PASID)
+		iommu_sva_unbind_device(q->handle);
+#endif
+
+	if (uacce->ops->put_queue)
+		uacce->ops->put_queue(q);
+
+	atomic_set(&uacce->state, UACCE_ST_INIT);
+	module_put(uacce->pdev->driver->owner);
+
+	return 0;
+}
+
+static enum uacce_qfrt uacce_get_region_type(struct uacce_device *uacce,
+					     struct vm_area_struct *vma)
+{
+	enum uacce_qfrt type = UACCE_QFRT_MAX;
+	size_t next_start = UACCE_QFR_NA;
+	int i;
+
+	for (i = UACCE_QFRT_MAX - 1; i >= 0; i--) {
+		if (vma->vm_pgoff >= uacce->qf_pg_start[i]) {
+			type = i;
+			break;
+		}
+	}
+
+	switch (type) {
+	case UACCE_QFRT_MMIO:
+		if (!uacce->ops->mmap) {
+			dev_err(&uacce->dev, "no driver mmap!\n");
+			return UACCE_QFRT_MAX;
+		}
+		break;
+
+	case UACCE_QFRT_DKO:
+		if (uacce->flags & UACCE_DEV_PASID)
+			return UACCE_QFRT_MAX;
+		break;
+
+	case UACCE_QFRT_DUS:
+		break;
+
+	case UACCE_QFRT_SS:
+		/* todo: this can be valid to protect the process space */
+		if (uacce->flags & UACCE_DEV_FAULT_FROM_DEV)
+			return UACCE_QFRT_MAX;
+		break;
+
+	default:
+		dev_err(&uacce->dev, "uacce bug (%d)!\n", type);
+		return UACCE_QFRT_MAX;
+	}
+
+	/* make sure the mapping size is exactly the same as the region */
+	if (type < UACCE_QFRT_SS) {
+		for (i = type + 1; i < UACCE_QFRT_MAX; i++)
+			if (uacce->qf_pg_start[i] != UACCE_QFR_NA) {
+				next_start = uacce->qf_pg_start[i];
+				break;
+			}
+
+		if (next_start == UACCE_QFR_NA) {
+			dev_err(&uacce->dev, "uacce config error: SS offset set improperly\n");
+			return UACCE_QFRT_MAX;
+		}
+
+		if (vma_pages(vma) !=
+		    next_start - uacce->qf_pg_start[type]) {
+			dev_err(&uacce->dev, "invalid mmap size (%ld vs %ld pages) for region %s.\n",
+				vma_pages(vma),
+				next_start - uacce->qf_pg_start[type],
+				qfrt_str[type]);
+			return UACCE_QFRT_MAX;
+		}
+	}
+
+	return type;
+}
+
+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;
+	enum uacce_qfrt type = uacce_get_region_type(uacce, vma);
+	struct uacce_qfile_region *qfr;
+	unsigned int flags = 0;
+	int ret;
+
+	if (type == UACCE_QFRT_MAX)
+		return -EINVAL;
+
+	vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND;
+
+	mutex_lock(&uacce_mutex);
+
+	/* fixme: if the region need no pages, we don't need to check it */
+	if (q->mm->data_vm + vma_pages(vma) >
+	    rlimit(RLIMIT_DATA) >> PAGE_SHIFT) {
+		ret = -ENOMEM;
+		goto out_with_lock;
+	}
+
+	if (q->qfrs[type]) {
+		ret = -EBUSY;
+		goto out_with_lock;
+	}
+
+	switch (type) {
+	case UACCE_QFRT_MMIO:
+		flags = UACCE_QFRF_SELFMT;
+		break;
+
+	case UACCE_QFRT_SS:
+		if (atomic_read(&uacce->state) != UACCE_ST_STARTED) {
+			ret = -EINVAL;
+			goto out_with_lock;
+		}
+
+		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;
+
+		break;
+
+	case UACCE_QFRT_DKO:
+		flags = UACCE_QFRF_MAP | UACCE_QFRF_KMAP;
+
+		break;
+
+	case UACCE_QFRT_DUS:
+		if (uacce->flags & UACCE_DEV_PASID) {
+			flags = UACCE_QFRF_SELFMT;
+			break;
+		}
+
+		flags = UACCE_QFRF_MAP | UACCE_QFRF_MMAP;
+		break;
+
+	default:
+		WARN_ON(&uacce->dev);
+		break;
+	}
+
+	qfr = uacce_create_region(q, vma, type, flags);
+	if (IS_ERR(qfr)) {
+		ret = PTR_ERR(qfr);
+		goto out_with_lock;
+	}
+	q->qfrs[type] = qfr;
+
+	if (type == UACCE_QFRT_SS) {
+		INIT_LIST_HEAD(&qfr->qs);
+		list_add(&q->list, &q->qfrs[type]->qs);
+	}
+
+	mutex_unlock(&uacce_mutex);
+
+	if (qfr->pages)
+		q->mm->data_vm += qfr->nr_pages;
+
+	return 0;
+
+out_with_lock:
+	mutex_unlock(&uacce_mutex);
+	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 UACCE_FROM_CDEV_ATTR(dev) container_of(dev, struct uacce_device, dev)
+
+static ssize_t id_show(struct device *dev,
+		       struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+
+	return sprintf(buf, "%d\n", uacce->dev_id);
+}
+
+static ssize_t api_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+
+	return sprintf(buf, "%s\n", uacce->api_ver);
+}
+
+static ssize_t numa_distance_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+	int distance;
+
+	distance = node_distance(smp_processor_id(), uacce->pdev->numa_node);
+
+	return sprintf(buf, "%d\n", abs(distance));
+}
+
+static ssize_t node_id_show(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+	int node_id;
+
+	node_id = dev_to_node(uacce->pdev);
+
+	return sprintf(buf, "%d\n", node_id);
+}
+
+static ssize_t flags_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+
+	return sprintf(buf, "%d\n", uacce->flags);
+}
+
+static ssize_t available_instances_show(struct device *dev,
+					struct device_attribute *attr,
+					char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+	int val = 0;
+
+	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 = UACCE_FROM_CDEV_ATTR(dev);
+
+	return sprintf(buf, "%s", uacce->algs);
+}
+
+static ssize_t qfrs_offset_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+	int i, ret;
+	unsigned long offset;
+
+	for (i = 0, ret = 0; i < UACCE_QFRT_MAX; i++) {
+		offset = uacce->qf_pg_start[i];
+		if (offset != UACCE_QFR_NA)
+			offset = offset << PAGE_SHIFT;
+		if (i == UACCE_QFRT_SS)
+			break;
+		ret += sprintf(buf + ret, "%lu\t", offset);
+	}
+	ret += sprintf(buf + ret, "%lu\n", offset);
+
+	return ret;
+}
+
+static DEVICE_ATTR_RO(id);
+static DEVICE_ATTR_RO(api);
+static DEVICE_ATTR_RO(numa_distance);
+static DEVICE_ATTR_RO(node_id);
+static DEVICE_ATTR_RO(flags);
+static DEVICE_ATTR_RO(available_instances);
+static DEVICE_ATTR_RO(algorithms);
+static DEVICE_ATTR_RO(qfrs_offset);
+
+static struct attribute *uacce_dev_attrs[] = {
+	&dev_attr_id.attr,
+	&dev_attr_api.attr,
+	&dev_attr_node_id.attr,
+	&dev_attr_numa_distance.attr,
+	&dev_attr_flags.attr,
+	&dev_attr_available_instances.attr,
+	&dev_attr_algorithms.attr,
+	&dev_attr_qfrs_offset.attr,
+	NULL,
+};
+
+static const struct attribute_group uacce_dev_attr_group = {
+	.attrs	= uacce_dev_attrs,
+};
+
+static const struct attribute_group *uacce_dev_attr_groups[] = {
+	&uacce_dev_attr_group,
+	NULL
+};
+
+static void uacce_release(struct device *dev)
+{
+	struct uacce_device *uacce = UACCE_FROM_CDEV_ATTR(dev);
+
+	idr_remove(&uacce_idr, uacce->dev_id);
+	kfree(uacce);
+}
+
+static int uacce_create_chrdev(struct uacce_device *uacce)
+{
+	int ret;
+
+	ret = idr_alloc(&uacce_idr, uacce, 0, 0, GFP_KERNEL);
+	if (ret < 0)
+		return ret;
+
+	uacce->cdev = cdev_alloc();
+	uacce->cdev->ops = &uacce_fops;
+	uacce->dev_id = ret;
+	uacce->cdev->owner = THIS_MODULE;
+	device_initialize(&uacce->dev);
+	uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);
+	uacce->dev.class = uacce_class;
+	uacce->dev.groups = uacce_dev_attr_groups;
+	uacce->dev.parent = uacce->pdev;
+	uacce->dev.release = uacce_release;
+	dev_set_name(&uacce->dev, "%s-%d", uacce->drv_name, uacce->dev_id);
+	ret = cdev_device_add(uacce->cdev, &uacce->dev);
+	if (ret)
+		goto err_with_idr;
+
+	dev_dbg(&uacce->dev, "create uacce minior=%d\n", uacce->dev_id);
+
+	return 0;
+
+err_with_idr:
+	idr_remove(&uacce_idr, uacce->dev_id);
+	return ret;
+}
+
+static void uacce_destroy_chrdev(struct uacce_device *uacce)
+{
+	cdev_device_del(uacce->cdev, &uacce->dev);
+	put_device(&uacce->dev);
+}
+
+static int uacce_dev_match(struct device *dev, void *data)
+{
+	if (dev->parent == data)
+		return -EBUSY;
+
+	return 0;
+}
+
+/* Borrowed from VFIO to fix msi translation */
+static bool uacce_iommu_has_sw_msi(struct iommu_group *group,
+				   phys_addr_t *base)
+{
+	struct list_head group_resv_regions;
+	struct iommu_resv_region *region, *next;
+	bool ret = false;
+
+	INIT_LIST_HEAD(&group_resv_regions);
+	iommu_get_group_resv_regions(group, &group_resv_regions);
+	list_for_each_entry(region, &group_resv_regions, list) {
+		pr_debug("uacce: find a resv region (%d) on %llx\n",
+			 region->type, region->start);
+
+		/*
+		 * The presence of any 'real' MSI regions should take
+		 * precedence over the software-managed one if the
+		 * IOMMU driver happens to advertise both types.
+		 */
+		if (region->type == IOMMU_RESV_MSI) {
+			ret = false;
+			break;
+		}
+
+		if (region->type == IOMMU_RESV_SW_MSI) {
+			*base = region->start;
+			ret = true;
+		}
+	}
+	list_for_each_entry_safe(region, next, &group_resv_regions, list)
+		kfree(region);
+
+	return ret;
+}
+
+static int uacce_set_iommu_domain(struct uacce_device *uacce)
+{
+	struct iommu_domain *domain;
+	struct iommu_group *group;
+	struct device *dev = uacce->pdev;
+	bool resv_msi;
+	phys_addr_t resv_msi_base = 0;
+	int ret;
+
+	if (uacce->flags & UACCE_DEV_PASID)
+		return 0;
+
+	/*
+	 * We don't support multiple register for the same dev if no pasid
+	 */
+	ret = class_for_each_device(uacce_class, NULL, uacce->pdev,
+				    uacce_dev_match);
+	if (ret)
+		return ret;
+
+	/* allocate and attach a unmanged domain */
+	domain = iommu_domain_alloc(uacce->pdev->bus);
+	if (!domain) {
+		dev_err(&uacce->dev, "cannot get domain for iommu\n");
+		return -ENODEV;
+	}
+
+	ret = iommu_attach_device(domain, uacce->pdev);
+	if (ret)
+		goto err_with_domain;
+
+	if (iommu_capable(dev->bus, IOMMU_CAP_CACHE_COHERENCY))
+		uacce->prot |= IOMMU_CACHE;
+
+	group = iommu_group_get(dev);
+	if (!group) {
+		ret = -EINVAL;
+		goto err_with_domain;
+	}
+
+	resv_msi = uacce_iommu_has_sw_msi(group, &resv_msi_base);
+	iommu_group_put(group);
+
+	if (resv_msi) {
+		if (!irq_domain_check_msi_remap() &&
+		    !iommu_capable(dev->bus, IOMMU_CAP_INTR_REMAP)) {
+			dev_warn(dev, "No interrupt remapping support!");
+			ret = -EPERM;
+			goto err_with_domain;
+		}
+
+		ret = iommu_get_msi_cookie(domain, resv_msi_base);
+		if (ret)
+			goto err_with_domain;
+	}
+
+	return 0;
+
+err_with_domain:
+	iommu_domain_free(domain);
+	return ret;
+}
+
+static void uacce_unset_iommu_domain(struct uacce_device *uacce)
+{
+	struct iommu_domain *domain;
+
+	if (uacce->flags & UACCE_DEV_PASID)
+		return;
+
+	domain = iommu_get_domain_for_dev(uacce->pdev);
+	if (!domain) {
+		dev_err(&uacce->dev, "bug: no domain attached to device\n");
+		return;
+	}
+
+	iommu_detach_device(domain, uacce->pdev);
+	iommu_domain_free(domain);
+}
+
+/**
+ *	uacce_register - register an accelerator
+ *	@uacce: the accelerator structure
+ */
+struct uacce_device *uacce_register(struct device *parent,
+				    struct uacce_interface *interface)
+{
+	int ret, i;
+	struct uacce_device *uacce;
+	unsigned int flags = interface->flags;
+
+	/* if dev support fault-from-dev, it should support pasid */
+	if ((flags & UACCE_DEV_FAULT_FROM_DEV) && !(flags & UACCE_DEV_PASID)) {
+		dev_warn(parent, "SVM/SAV device should support PASID\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+#ifdef CONFIG_IOMMU_SVA
+	if (flags & UACCE_DEV_PASID) {
+		ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);
+		if (ret)
+			flags &= ~(UACCE_DEV_FAULT_FROM_DEV |
+				   UACCE_DEV_PASID);
+	}
+#endif
+	uacce = kzalloc(sizeof(struct uacce_device), GFP_KERNEL);
+	if (!uacce)
+		return ERR_PTR(-ENOMEM);
+
+	uacce->pdev = parent;
+	uacce->flags = flags;
+	uacce->ops = interface->ops;
+	uacce->drv_name = interface->name;
+
+	for (i = 0; i < UACCE_QFRT_MAX; i++)
+		uacce->qf_pg_start[i] = UACCE_QFR_NA;
+
+	ret = uacce_set_iommu_domain(uacce);
+	if (ret)
+		goto err_free;
+
+	mutex_lock(&uacce_mutex);
+
+	ret = uacce_create_chrdev(uacce);
+	if (ret)
+		goto err_with_lock;
+
+	atomic_set(&uacce->state, UACCE_ST_INIT);
+	INIT_LIST_HEAD(&uacce->qs);
+	mutex_init(&uacce->q_lock);
+
+	mutex_unlock(&uacce_mutex);
+
+	return uacce;
+
+err_with_lock:
+	mutex_unlock(&uacce_mutex);
+err_free:
+	kfree(uacce);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(uacce_register);
+
+/**
+ * uacce_unregister - unregisters a uacce
+ * @uacce: the accelerator to unregister
+ *
+ * Unregister an accelerator that wat previously successully registered with
+ * uacce_register().
+ */
+void uacce_unregister(struct uacce_device *uacce)
+{
+	mutex_lock(&uacce_mutex);
+
+#ifdef CONFIG_IOMMU_SVA
+	if (uacce->flags & UACCE_DEV_PASID)
+		iommu_dev_disable_feature(uacce->pdev, IOMMU_DEV_FEAT_SVA);
+#endif
+	uacce_unset_iommu_domain(uacce);
+	uacce_destroy_chrdev(uacce);
+
+	mutex_unlock(&uacce_mutex);
+}
+EXPORT_SYMBOL_GPL(uacce_unregister);
+
+static int __init uacce_init(void)
+{
+	int ret;
+
+	uacce_class = class_create(THIS_MODULE, UACCE_NAME);
+	if (IS_ERR(uacce_class)) {
+		ret = PTR_ERR(uacce_class);
+		goto err;
+	}
+
+	ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);
+	if (ret)
+		goto err_with_class;
+
+	pr_info("uacce init with major number:%d\n", MAJOR(uacce_devt));
+
+	return 0;
+
+err_with_class:
+	class_destroy(uacce_class);
+err:
+	return ret;
+}
+
+static __exit void uacce_exit(void)
+{
+	unregister_chrdev_region(uacce_devt, MINORMASK);
+	class_destroy(uacce_class);
+	idr_destroy(&uacce_idr);
+}
+
+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..b23a28b
--- /dev/null
+++ b/include/linux/uacce.h
@@ -0,0 +1,172 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __UACCE_H
+#define __UACCE_H
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <linux/iommu.h>
+#include <uapi/misc/uacce.h>
+
+#define UACCE_NAME		"uacce"
+
+struct uacce_queue;
+struct uacce_device;
+
+/* uacce mode of the driver */
+#define UACCE_MODE_NOUACCE	0 /* don't use uacce */
+#define UACCE_MODE_UACCE	1 /* use uacce exclusively */
+
+/* uacce queue file flag, requires different operation */
+#define UACCE_QFRF_MAP		BIT(0)	/* map to current queue */
+#define UACCE_QFRF_MMAP		BIT(1)	/* map to user space */
+#define UACCE_QFRF_KMAP		BIT(2)	/* map to kernel space */
+#define UACCE_QFRF_DMA		BIT(3)	/* use dma api for the region */
+#define UACCE_QFRF_SELFMT	BIT(4)	/* self maintained qfr */
+
+/**
+ * struct uacce_qfile_region - structure of queue file region
+ * @type: type of the qfr
+ * @iova: iova share between user and device space
+ * @pages: pages pointer of the qfr memory
+ * @nr_pages: page numbers of the qfr memory
+ * @prot: qfr protection flag
+ * @flags: flags of qfr
+ * @qs: list sharing the same region, for ss region
+ * @kaddr: kernel addr of the qfr
+ * @dma: dma address, if created by dma api
+ */
+struct uacce_qfile_region {
+	enum uacce_qfrt type;
+	unsigned long iova;
+	struct page **pages;
+	int nr_pages;
+	int prot;
+	unsigned int flags;
+	struct list_head qs;
+	void *kaddr;
+	dma_addr_t dma;
+};
+
+/**
+ * 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
+ * @mask_notify: mask the task irq of queue
+ * @mmap: mmap addresses of queue to user space
+ * @reset: reset the uacce device
+ * @reset_queue: reset the queue
+ * @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);
+	void (*mask_notify)(struct uacce_queue *q, int event_mask);
+	int (*mmap)(struct uacce_queue *q, struct vm_area_struct *vma,
+		    struct uacce_qfile_region *qfr);
+	int (*reset)(struct uacce_device *uacce);
+	int (*reset_queue)(struct uacce_queue *q);
+	long (*ioctl)(struct uacce_queue *q, unsigned int cmd,
+		      unsigned long arg);
+};
+
+/**
+ * struct uacce_interface
+ * @name: the uacce device name.  Will show up in sysfs
+ * @flags: uacce device attributes
+ * @ops: pointer to the struct uacce_ops
+ *
+ * This structure is used for the uacce_register()
+ */
+struct uacce_interface {
+	char name[32];
+	unsigned int flags;
+	struct uacce_ops *ops;
+};
+
+/**
+ * struct uacce_queue
+ * @uacce: pointer to uacce
+ * @priv: private pointer
+ * @wait: wait queue head
+ * @pasid: pasid of the queue
+ * @handle: iommu_sva handle return from iommu_sva_bind_device
+ * @list: share list for qfr->qs
+ * @mm: current->mm
+ * @qfrs: pointer of qfr regions
+ * @q_dev: list for uacce->qs
+ */
+struct uacce_queue {
+	struct uacce_device *uacce;
+	void *priv;
+	wait_queue_head_t wait;
+	int pasid;
+	struct iommu_sva *handle;
+	struct list_head list;
+	struct mm_struct *mm;
+	struct uacce_qfile_region *qfrs[UACCE_QFRT_MAX];
+	struct list_head q_dev;
+};
+
+/* uacce state */
+enum {
+	UACCE_ST_INIT = 0,
+	UACCE_ST_OPENED,
+	UACCE_ST_STARTED,
+	UACCE_ST_RST,
+};
+
+/**
+ * struct uacce_device
+ * @drv_name: the uacce driver name.  Will show up in sysfs
+ * @algs: supported algorithms
+ * @api_ver: api version
+ * @flags: uacce attributes
+ * @qf_pg_start: page start of the queue file regions
+ * @ops: pointer to the struct uacce_ops
+ * @pdev: pointer to the parent device
+ * @is_vf: whether virtual function
+ * @dev_id: id of the uacce device
+ * @cdev: cdev of the uacce
+ * @dev: dev of the uacce
+ * @priv: private pointer of the uacce
+ * @state: uacce state
+ * @prot: uacce protection flag
+ * @q_lock: uacce mutex lock for queue
+ * @qs: uacce list head for share
+ */
+struct uacce_device {
+	const char *drv_name;
+	const char *algs;
+	const char *api_ver;
+	unsigned int flags;
+	unsigned long qf_pg_start[UACCE_QFRT_MAX];
+	struct uacce_ops *ops;
+	struct device *pdev;
+	bool is_vf;
+	u32 dev_id;
+	struct cdev *cdev;
+	struct device dev;
+	void *priv;
+	atomic_t state;
+	int prot;
+	struct mutex q_lock;
+	struct list_head qs;
+};
+
+struct uacce_device *uacce_register(struct device *parent,
+				    struct uacce_interface *interface);
+void uacce_unregister(struct uacce_device *uacce);
+void uacce_wake_up(struct uacce_queue *q);
+
+#endif
diff --git a/include/uapi/misc/uacce.h b/include/uapi/misc/uacce.h
new file mode 100644
index 0000000..685b4a1
--- /dev/null
+++ b/include/uapi/misc/uacce.h
@@ -0,0 +1,39 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _UAPIUUACCE_H
+#define _UAPIUUACCE_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define UACCE_CMD_SHARE_SVAS	_IO('W', 0)
+#define UACCE_CMD_START		_IO('W', 1)
+
+/**
+ * UACCE Device Attributes:
+ *
+ * SHARE_DOMAIN: no PASID, can shae sva only for one process and the kernel
+ * PASID: the device has IOMMU which support PASID setting
+ *	  can do share sva, mapped to dev per process
+ * FAULT_FROM_DEV: the device has IOMMU which can do page fault request
+ *		   no need for share sva, should be used with PASID
+ * SVA: full function device
+ */
+
+enum {
+	UACCE_DEV_SHARE_DOMAIN = 0x0,
+	UACCE_DEV_PASID = 0x1,
+	UACCE_DEV_FAULT_FROM_DEV = 0x2,
+	UACCE_DEV_SVA = UACCE_DEV_PASID | UACCE_DEV_FAULT_FROM_DEV,
+};
+
+#define UACCE_QFR_NA ((unsigned long)-1)
+
+enum uacce_qfrt {
+	UACCE_QFRT_MMIO = 0,	/* device mmio region */
+	UACCE_QFRT_DKO = 1,	/* device kernel-only */
+	UACCE_QFRT_DUS = 2,	/* device user share */
+	UACCE_QFRT_SS = 3,	/* static share memory */
+	UACCE_QFRT_MAX,
+};
+
+#endif