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path: root/drivers/misc/uacce/uacce.c
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Diffstat (limited to 'drivers/misc/uacce/uacce.c')
-rw-r--r--drivers/misc/uacce/uacce.c633
1 files changed, 633 insertions, 0 deletions
diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
new file mode 100644
index 000000000000..d39307f060bd
--- /dev/null
+++ b/drivers/misc/uacce/uacce.c
@@ -0,0 +1,633 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/compat.h>
+#include <linux/dma-mapping.h>
+#include <linux/iommu.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/uacce.h>
+
+static struct class *uacce_class;
+static dev_t uacce_devt;
+static DEFINE_MUTEX(uacce_mutex);
+static DEFINE_XARRAY_ALLOC(uacce_xa);
+
+static int uacce_start_queue(struct uacce_queue *q)
+{
+ int ret = 0;
+
+ mutex_lock(&uacce_mutex);
+
+ if (q->state != UACCE_Q_INIT) {
+ ret = -EINVAL;
+ goto out_with_lock;
+ }
+
+ if (q->uacce->ops->start_queue) {
+ ret = q->uacce->ops->start_queue(q);
+ if (ret < 0)
+ goto out_with_lock;
+ }
+
+ q->state = UACCE_Q_STARTED;
+
+out_with_lock:
+ mutex_unlock(&uacce_mutex);
+
+ return ret;
+}
+
+static int uacce_put_queue(struct uacce_queue *q)
+{
+ struct uacce_device *uacce = q->uacce;
+
+ mutex_lock(&uacce_mutex);
+
+ if (q->state == UACCE_Q_ZOMBIE)
+ goto out;
+
+ if ((q->state == UACCE_Q_STARTED) && uacce->ops->stop_queue)
+ uacce->ops->stop_queue(q);
+
+ if ((q->state == UACCE_Q_INIT || q->state == UACCE_Q_STARTED) &&
+ uacce->ops->put_queue)
+ uacce->ops->put_queue(q);
+
+ q->state = UACCE_Q_ZOMBIE;
+out:
+ mutex_unlock(&uacce_mutex);
+
+ return 0;
+}
+
+static long uacce_fops_unl_ioctl(struct file *filep,
+ unsigned int cmd, unsigned long arg)
+{
+ struct uacce_queue *q = filep->private_data;
+ struct uacce_device *uacce = q->uacce;
+
+ switch (cmd) {
+ case UACCE_CMD_START_Q:
+ return uacce_start_queue(q);
+
+ case UACCE_CMD_PUT_Q:
+ return uacce_put_queue(q);
+
+ default:
+ if (!uacce->ops->ioctl)
+ return -EINVAL;
+
+ return uacce->ops->ioctl(q, cmd, arg);
+ }
+}
+
+#ifdef CONFIG_COMPAT
+static long uacce_fops_compat_ioctl(struct file *filep,
+ unsigned int cmd, unsigned long arg)
+{
+ arg = (unsigned long)compat_ptr(arg);
+
+ return uacce_fops_unl_ioctl(filep, cmd, arg);
+}
+#endif
+
+static int uacce_sva_exit(struct device *dev, struct iommu_sva *handle,
+ void *data)
+{
+ struct uacce_mm *uacce_mm = data;
+ struct uacce_queue *q;
+
+ /*
+ * No new queue can be added concurrently because no caller can have a
+ * reference to this mm. But there may be concurrent calls to
+ * uacce_mm_put(), so we need the lock.
+ */
+ mutex_lock(&uacce_mm->lock);
+ list_for_each_entry(q, &uacce_mm->queues, list)
+ uacce_put_queue(q);
+ uacce_mm->mm = NULL;
+ mutex_unlock(&uacce_mm->lock);
+
+ return 0;
+}
+
+static struct iommu_sva_ops uacce_sva_ops = {
+ .mm_exit = uacce_sva_exit,
+};
+
+static struct uacce_mm *uacce_mm_get(struct uacce_device *uacce,
+ struct uacce_queue *q,
+ struct mm_struct *mm)
+{
+ struct uacce_mm *uacce_mm = NULL;
+ struct iommu_sva *handle = NULL;
+ int ret;
+
+ lockdep_assert_held(&uacce->mm_lock);
+
+ list_for_each_entry(uacce_mm, &uacce->mm_list, list) {
+ if (uacce_mm->mm == mm) {
+ mutex_lock(&uacce_mm->lock);
+ list_add(&q->list, &uacce_mm->queues);
+ mutex_unlock(&uacce_mm->lock);
+ return uacce_mm;
+ }
+ }
+
+ uacce_mm = kzalloc(sizeof(*uacce_mm), GFP_KERNEL);
+ if (!uacce_mm)
+ return NULL;
+
+ if (uacce->flags & UACCE_DEV_SVA) {
+ /*
+ * Safe to pass an incomplete uacce_mm, since mm_exit cannot
+ * fire while we hold a reference to the mm.
+ */
+ handle = iommu_sva_bind_device(uacce->parent, mm, uacce_mm);
+ if (IS_ERR(handle))
+ goto err_free;
+
+ ret = iommu_sva_set_ops(handle, &uacce_sva_ops);
+ if (ret)
+ goto err_unbind;
+
+ uacce_mm->pasid = iommu_sva_get_pasid(handle);
+ if (uacce_mm->pasid == IOMMU_PASID_INVALID)
+ goto err_unbind;
+ }
+
+ uacce_mm->mm = mm;
+ uacce_mm->handle = handle;
+ INIT_LIST_HEAD(&uacce_mm->queues);
+ mutex_init(&uacce_mm->lock);
+ list_add(&q->list, &uacce_mm->queues);
+ list_add(&uacce_mm->list, &uacce->mm_list);
+
+ return uacce_mm;
+
+err_unbind:
+ if (handle)
+ iommu_sva_unbind_device(handle);
+err_free:
+ kfree(uacce_mm);
+ return NULL;
+}
+
+static void uacce_mm_put(struct uacce_queue *q)
+{
+ struct uacce_mm *uacce_mm = q->uacce_mm;
+
+ lockdep_assert_held(&q->uacce->mm_lock);
+
+ mutex_lock(&uacce_mm->lock);
+ list_del(&q->list);
+ mutex_unlock(&uacce_mm->lock);
+
+ if (list_empty(&uacce_mm->queues)) {
+ if (uacce_mm->handle)
+ iommu_sva_unbind_device(uacce_mm->handle);
+ list_del(&uacce_mm->list);
+ kfree(uacce_mm);
+ }
+}
+
+static int uacce_fops_open(struct inode *inode, struct file *filep)
+{
+ struct uacce_mm *uacce_mm = NULL;
+ struct uacce_device *uacce;
+ struct uacce_queue *q;
+ int ret = 0;
+
+ uacce = xa_load(&uacce_xa, iminor(inode));
+ if (!uacce)
+ return -ENODEV;
+
+ q = kzalloc(sizeof(struct uacce_queue), GFP_KERNEL);
+ if (!q)
+ return -ENOMEM;
+
+ mutex_lock(&uacce->mm_lock);
+ uacce_mm = uacce_mm_get(uacce, q, current->mm);
+ mutex_unlock(&uacce->mm_lock);
+ if (!uacce_mm) {
+ ret = -ENOMEM;
+ goto out_with_mem;
+ }
+
+ q->uacce = uacce;
+ q->uacce_mm = uacce_mm;
+
+ if (uacce->ops->get_queue) {
+ ret = uacce->ops->get_queue(uacce, uacce_mm->pasid, q);
+ if (ret < 0)
+ goto out_with_mm;
+ }
+
+ init_waitqueue_head(&q->wait);
+ filep->private_data = q;
+ uacce->inode = inode;
+ q->state = UACCE_Q_INIT;
+
+ return 0;
+
+out_with_mm:
+ mutex_lock(&uacce->mm_lock);
+ uacce_mm_put(q);
+ mutex_unlock(&uacce->mm_lock);
+out_with_mem:
+ kfree(q);
+ return ret;
+}
+
+static int uacce_fops_release(struct inode *inode, struct file *filep)
+{
+ struct uacce_queue *q = filep->private_data;
+ struct uacce_device *uacce = q->uacce;
+
+ uacce_put_queue(q);
+
+ mutex_lock(&uacce->mm_lock);
+ uacce_mm_put(q);
+ mutex_unlock(&uacce->mm_lock);
+
+ kfree(q);
+
+ return 0;
+}
+
+static vm_fault_t uacce_vma_fault(struct vm_fault *vmf)
+{
+ if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
+ return VM_FAULT_SIGBUS;
+
+ return 0;
+}
+
+static void uacce_vma_close(struct vm_area_struct *vma)
+{
+ struct uacce_queue *q = vma->vm_private_data;
+ struct uacce_qfile_region *qfr = NULL;
+
+ if (vma->vm_pgoff < UACCE_MAX_REGION)
+ qfr = q->qfrs[vma->vm_pgoff];
+
+ kfree(qfr);
+}
+
+static const struct vm_operations_struct uacce_vm_ops = {
+ .fault = uacce_vma_fault,
+ .close = uacce_vma_close,
+};
+
+static int uacce_fops_mmap(struct file *filep, struct vm_area_struct *vma)
+{
+ struct uacce_queue *q = filep->private_data;
+ struct uacce_device *uacce = q->uacce;
+ struct uacce_qfile_region *qfr;
+ enum uacce_qfrt type = UACCE_MAX_REGION;
+ int ret = 0;
+
+ if (vma->vm_pgoff < UACCE_MAX_REGION)
+ type = vma->vm_pgoff;
+ else
+ return -EINVAL;
+
+ qfr = kzalloc(sizeof(*qfr), GFP_KERNEL);
+ if (!qfr)
+ return -ENOMEM;
+
+ vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_WIPEONFORK;
+ vma->vm_ops = &uacce_vm_ops;
+ vma->vm_private_data = q;
+ qfr->type = type;
+
+ mutex_lock(&uacce_mutex);
+
+ if (q->state != UACCE_Q_INIT && q->state != UACCE_Q_STARTED) {
+ ret = -EINVAL;
+ goto out_with_lock;
+ }
+
+ if (q->qfrs[type]) {
+ ret = -EEXIST;
+ goto out_with_lock;
+ }
+
+ switch (type) {
+ case UACCE_QFRT_MMIO:
+ if (!uacce->ops->mmap) {
+ ret = -EINVAL;
+ goto out_with_lock;
+ }
+
+ ret = uacce->ops->mmap(q, vma, qfr);
+ if (ret)
+ goto out_with_lock;
+
+ break;
+
+ case UACCE_QFRT_DUS:
+ if (!uacce->ops->mmap) {
+ ret = -EINVAL;
+ goto out_with_lock;
+ }
+
+ ret = uacce->ops->mmap(q, vma, qfr);
+ if (ret)
+ goto out_with_lock;
+ break;
+
+ default:
+ ret = -EINVAL;
+ goto out_with_lock;
+ }
+
+ q->qfrs[type] = qfr;
+ mutex_unlock(&uacce_mutex);
+
+ return ret;
+
+out_with_lock:
+ mutex_unlock(&uacce_mutex);
+ kfree(qfr);
+ return ret;
+}
+
+static __poll_t uacce_fops_poll(struct file *file, poll_table *wait)
+{
+ struct uacce_queue *q = file->private_data;
+ struct uacce_device *uacce = q->uacce;
+
+ poll_wait(file, &q->wait, wait);
+ if (uacce->ops->is_q_updated && uacce->ops->is_q_updated(q))
+ return EPOLLIN | EPOLLRDNORM;
+
+ return 0;
+}
+
+static const struct file_operations uacce_fops = {
+ .owner = THIS_MODULE,
+ .open = uacce_fops_open,
+ .release = uacce_fops_release,
+ .unlocked_ioctl = uacce_fops_unl_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = uacce_fops_compat_ioctl,
+#endif
+ .mmap = uacce_fops_mmap,
+ .poll = uacce_fops_poll,
+};
+
+#define to_uacce_device(dev) container_of(dev, struct uacce_device, dev)
+
+static ssize_t api_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ return sprintf(buf, "%s\n", uacce->api_ver);
+}
+
+static ssize_t flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ return sprintf(buf, "%u\n", uacce->flags);
+}
+
+static ssize_t available_instances_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ if (!uacce->ops->get_available_instances)
+ return -ENODEV;
+
+ return sprintf(buf, "%d\n",
+ uacce->ops->get_available_instances(uacce));
+}
+
+static ssize_t algorithms_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ return sprintf(buf, "%s\n", uacce->algs);
+}
+
+static ssize_t region_mmio_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ return sprintf(buf, "%lu\n",
+ uacce->qf_pg_num[UACCE_QFRT_MMIO] << PAGE_SHIFT);
+}
+
+static ssize_t region_dus_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ return sprintf(buf, "%lu\n",
+ uacce->qf_pg_num[UACCE_QFRT_DUS] << PAGE_SHIFT);
+}
+
+static DEVICE_ATTR_RO(api);
+static DEVICE_ATTR_RO(flags);
+static DEVICE_ATTR_RO(available_instances);
+static DEVICE_ATTR_RO(algorithms);
+static DEVICE_ATTR_RO(region_mmio_size);
+static DEVICE_ATTR_RO(region_dus_size);
+
+static struct attribute *uacce_dev_attrs[] = {
+ &dev_attr_api.attr,
+ &dev_attr_flags.attr,
+ &dev_attr_available_instances.attr,
+ &dev_attr_algorithms.attr,
+ &dev_attr_region_mmio_size.attr,
+ &dev_attr_region_dus_size.attr,
+ NULL,
+};
+
+static umode_t uacce_dev_is_visible(struct kobject *kobj,
+ struct attribute *attr, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ if (((attr == &dev_attr_region_mmio_size.attr) &&
+ (!uacce->qf_pg_num[UACCE_QFRT_MMIO])) ||
+ ((attr == &dev_attr_region_dus_size.attr) &&
+ (!uacce->qf_pg_num[UACCE_QFRT_DUS])))
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute_group uacce_dev_group = {
+ .is_visible = uacce_dev_is_visible,
+ .attrs = uacce_dev_attrs,
+};
+
+__ATTRIBUTE_GROUPS(uacce_dev);
+
+static void uacce_release(struct device *dev)
+{
+ struct uacce_device *uacce = to_uacce_device(dev);
+
+ kfree(uacce);
+}
+
+/**
+ * uacce_alloc() - alloc an accelerator
+ * @parent: pointer of uacce parent device
+ * @interface: pointer of uacce_interface for register
+ *
+ * Returns uacce pointer if success and ERR_PTR if not
+ * Need check returned negotiated uacce->flags
+ */
+struct uacce_device *uacce_alloc(struct device *parent,
+ struct uacce_interface *interface)
+{
+ unsigned int flags = interface->flags;
+ struct uacce_device *uacce;
+ int ret;
+
+ uacce = kzalloc(sizeof(struct uacce_device), GFP_KERNEL);
+ if (!uacce)
+ return ERR_PTR(-ENOMEM);
+
+ if (flags & UACCE_DEV_SVA) {
+ ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);
+ if (ret)
+ flags &= ~UACCE_DEV_SVA;
+ }
+
+ uacce->parent = parent;
+ uacce->flags = flags;
+ uacce->ops = interface->ops;
+
+ ret = xa_alloc(&uacce_xa, &uacce->dev_id, uacce, xa_limit_32b,
+ GFP_KERNEL);
+ if (ret < 0)
+ goto err_with_uacce;
+
+ INIT_LIST_HEAD(&uacce->mm_list);
+ mutex_init(&uacce->mm_lock);
+ device_initialize(&uacce->dev);
+ uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);
+ uacce->dev.class = uacce_class;
+ uacce->dev.groups = uacce_dev_groups;
+ uacce->dev.parent = uacce->parent;
+ uacce->dev.release = uacce_release;
+ dev_set_name(&uacce->dev, "%s-%d", interface->name, uacce->dev_id);
+
+ return uacce;
+
+err_with_uacce:
+ if (flags & UACCE_DEV_SVA)
+ iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+ kfree(uacce);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(uacce_alloc);
+
+/**
+ * uacce_register() - add the accelerator to cdev and export to user space
+ * @uacce: The initialized uacce device
+ *
+ * Return 0 if register succeeded, or an error.
+ */
+int uacce_register(struct uacce_device *uacce)
+{
+ if (!uacce)
+ return -ENODEV;
+
+ uacce->cdev = cdev_alloc();
+ if (!uacce->cdev)
+ return -ENOMEM;
+
+ uacce->cdev->ops = &uacce_fops;
+ uacce->cdev->owner = THIS_MODULE;
+
+ return cdev_device_add(uacce->cdev, &uacce->dev);
+}
+EXPORT_SYMBOL_GPL(uacce_register);
+
+/**
+ * uacce_remove() - remove the accelerator
+ * @uacce: the accelerator to remove
+ */
+void uacce_remove(struct uacce_device *uacce)
+{
+ struct uacce_mm *uacce_mm;
+ struct uacce_queue *q;
+
+ if (!uacce)
+ return;
+ /*
+ * unmap remaining mapping from user space, preventing user still
+ * access the mmaped area while parent device is already removed
+ */
+ if (uacce->inode)
+ unmap_mapping_range(uacce->inode->i_mapping, 0, 0, 1);
+
+ /* ensure no open queue remains */
+ mutex_lock(&uacce->mm_lock);
+ list_for_each_entry(uacce_mm, &uacce->mm_list, list) {
+ /*
+ * We don't take the uacce_mm->lock here. Since we hold the
+ * device's mm_lock, no queue can be added to or removed from
+ * this uacce_mm. We may run concurrently with mm_exit, but
+ * uacce_put_queue() is serialized and iommu_sva_unbind_device()
+ * waits for the lock that mm_exit is holding.
+ */
+ list_for_each_entry(q, &uacce_mm->queues, list)
+ uacce_put_queue(q);
+
+ if (uacce->flags & UACCE_DEV_SVA) {
+ iommu_sva_unbind_device(uacce_mm->handle);
+ uacce_mm->handle = NULL;
+ }
+ }
+ mutex_unlock(&uacce->mm_lock);
+
+ /* disable sva now since no opened queues */
+ if (uacce->flags & UACCE_DEV_SVA)
+ iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
+
+ if (uacce->cdev)
+ cdev_device_del(uacce->cdev, &uacce->dev);
+ xa_erase(&uacce_xa, uacce->dev_id);
+ put_device(&uacce->dev);
+}
+EXPORT_SYMBOL_GPL(uacce_remove);
+
+static int __init uacce_init(void)
+{
+ int ret;
+
+ uacce_class = class_create(THIS_MODULE, UACCE_NAME);
+ if (IS_ERR(uacce_class))
+ return PTR_ERR(uacce_class);
+
+ ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);
+ if (ret)
+ class_destroy(uacce_class);
+
+ return ret;
+}
+
+static __exit void uacce_exit(void)
+{
+ unregister_chrdev_region(uacce_devt, MINORMASK);
+ class_destroy(uacce_class);
+}
+
+subsys_initcall(uacce_init);
+module_exit(uacce_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hisilicon Tech. Co., Ltd.");
+MODULE_DESCRIPTION("Accelerator interface for Userland applications");