drivers/vfio/fsl-mc/vfio_fsl_mc.c - linux - Git at Google

 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
 /*
  * Copyright 2013-2016 Freescale Semiconductor Inc.
  * Copyright 2016-2017,2019-2020 NXP
  */

 #include <linux/device.h>
 #include <linux/iommu.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/vfio.h>
 #include <linux/fsl/mc.h>
 #include <linux/delay.h>
 #include <linux/io-64-nonatomic-hi-lo.h>

 #include "vfio_fsl_mc_private.h"

 static struct fsl_mc_driver vfio_fsl_mc_driver;

 static DEFINE_MUTEX(reflck_lock);

 static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
 {
 	kref_get(&reflck->kref);
 }

 static void vfio_fsl_mc_reflck_release(struct kref *kref)
 {
 	struct vfio_fsl_mc_reflck *reflck = container_of(kref,
 						      struct vfio_fsl_mc_reflck,
 						      kref);

 	mutex_destroy(&reflck->lock);
 	kfree(reflck);
 	mutex_unlock(&reflck_lock);
 }

 static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
 {
 	kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
 }

 static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
 {
 	struct vfio_fsl_mc_reflck *reflck;

 	reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
 	if (!reflck)
 		return ERR_PTR(-ENOMEM);

 	kref_init(&reflck->kref);
 	mutex_init(&reflck->lock);

 	return reflck;
 }

 static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
 {
 	int ret = 0;

 	mutex_lock(&reflck_lock);
 	if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
 		vdev->reflck = vfio_fsl_mc_reflck_alloc();
 		ret = PTR_ERR_OR_ZERO(vdev->reflck);
 	} else {
 		struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
 		struct vfio_device *device;
 		struct vfio_fsl_mc_device *cont_vdev;

 		device = vfio_device_get_from_dev(mc_cont_dev);
 		if (!device) {
 			ret = -ENODEV;
 			goto unlock;
 		}

 		cont_vdev = vfio_device_data(device);
 		if (!cont_vdev || !cont_vdev->reflck) {
 			vfio_device_put(device);
 			ret = -ENODEV;
 			goto unlock;
 		}
 		vfio_fsl_mc_reflck_get(cont_vdev->reflck);
 		vdev->reflck = cont_vdev->reflck;
 		vfio_device_put(device);
 	}

 unlock:
 	mutex_unlock(&reflck_lock);
 	return ret;
 }

 static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
 {
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	int count = mc_dev->obj_desc.region_count;
 	int i;

 	vdev->regions = kcalloc(count, sizeof(struct vfio_fsl_mc_region),
 				GFP_KERNEL);
 	if (!vdev->regions)
 		return -ENOMEM;

 	for (i = 0; i < count; i++) {
 		struct resource *res = &mc_dev->regions[i];
 		int no_mmap = is_fsl_mc_bus_dprc(mc_dev);

 		vdev->regions[i].addr = res->start;
 		vdev->regions[i].size = resource_size(res);
 		vdev->regions[i].type = mc_dev->regions[i].flags & IORESOURCE_BITS;
 		/*
 		 * Only regions addressed with PAGE granularity may be
 		 * MMAPed securely.
 		 */
 		if (!no_mmap && !(vdev->regions[i].addr & ~PAGE_MASK) &&
 				!(vdev->regions[i].size & ~PAGE_MASK))
 			vdev->regions[i].flags |=
 					VFIO_REGION_INFO_FLAG_MMAP;
 		vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
 		if (!(mc_dev->regions[i].flags & IORESOURCE_READONLY))
 			vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_WRITE;
 	}

 	return 0;
 }

 static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
 {
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	int i;

 	for (i = 0; i < mc_dev->obj_desc.region_count; i++)
 		iounmap(vdev->regions[i].ioaddr);
 	kfree(vdev->regions);
 }

 static int vfio_fsl_mc_open(void *device_data)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 	int ret;

 	if (!try_module_get(THIS_MODULE))
 		return -ENODEV;

 	mutex_lock(&vdev->reflck->lock);
 	if (!vdev->refcnt) {
 		ret = vfio_fsl_mc_regions_init(vdev);
 		if (ret)
 			goto err_reg_init;
 	}
 	vdev->refcnt++;

 	mutex_unlock(&vdev->reflck->lock);

 	return 0;

 err_reg_init:
 	mutex_unlock(&vdev->reflck->lock);
 	module_put(THIS_MODULE);
 	return ret;
 }

 static void vfio_fsl_mc_release(void *device_data)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 	int ret;

 	mutex_lock(&vdev->reflck->lock);

 	if (!(--vdev->refcnt)) {
 		struct fsl_mc_device *mc_dev = vdev->mc_dev;
 		struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
 		struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);

 		vfio_fsl_mc_regions_cleanup(vdev);

 		/* reset the device before cleaning up the interrupts */
 		ret = dprc_reset_container(mc_cont->mc_io, 0,
 		      mc_cont->mc_handle,
 			  mc_cont->obj_desc.id,
 			  DPRC_RESET_OPTION_NON_RECURSIVE);

 		if (ret) {
 			dev_warn(&mc_cont->dev, "VFIO_FLS_MC: reset device has failed (%d)\n",
 				 ret);
 			WARN_ON(1);
 		}

 		vfio_fsl_mc_irqs_cleanup(vdev);

 		fsl_mc_cleanup_irq_pool(mc_cont);
 	}

 	mutex_unlock(&vdev->reflck->lock);

 	module_put(THIS_MODULE);
 }

 static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 			      unsigned long arg)
 {
 	unsigned long minsz;
 	struct vfio_fsl_mc_device *vdev = device_data;
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;

 	switch (cmd) {
 	case VFIO_DEVICE_GET_INFO:
 	{
 		struct vfio_device_info info;

 		minsz = offsetofend(struct vfio_device_info, num_irqs);

 		if (copy_from_user(&info, (void __user *)arg, minsz))
 			return -EFAULT;

 		if (info.argsz < minsz)
 			return -EINVAL;

 		info.flags = VFIO_DEVICE_FLAGS_FSL_MC;

 		if (is_fsl_mc_bus_dprc(mc_dev))
 			info.flags |= VFIO_DEVICE_FLAGS_RESET;

 		info.num_regions = mc_dev->obj_desc.region_count;
 		info.num_irqs = mc_dev->obj_desc.irq_count;

 		return copy_to_user((void __user *)arg, &info, minsz) ?
 			-EFAULT : 0;
 	}
 	case VFIO_DEVICE_GET_REGION_INFO:
 	{
 		struct vfio_region_info info;

 		minsz = offsetofend(struct vfio_region_info, offset);

 		if (copy_from_user(&info, (void __user *)arg, minsz))
 			return -EFAULT;

 		if (info.argsz < minsz)
 			return -EINVAL;

 		if (info.index >= mc_dev->obj_desc.region_count)
 			return -EINVAL;

 		/* map offset to the physical address  */
 		info.offset = VFIO_FSL_MC_INDEX_TO_OFFSET(info.index);
 		info.size = vdev->regions[info.index].size;
 		info.flags = vdev->regions[info.index].flags;

 		if (copy_to_user((void __user *)arg, &info, minsz))
 			return -EFAULT;
 		return 0;
 	}
 	case VFIO_DEVICE_GET_IRQ_INFO:
 	{
 		struct vfio_irq_info info;

 		minsz = offsetofend(struct vfio_irq_info, count);
 		if (copy_from_user(&info, (void __user *)arg, minsz))
 			return -EFAULT;

 		if (info.argsz < minsz)
 			return -EINVAL;

 		if (info.index >= mc_dev->obj_desc.irq_count)
 			return -EINVAL;

 		info.flags = VFIO_IRQ_INFO_EVENTFD;
 		info.count = 1;

 		if (copy_to_user((void __user *)arg, &info, minsz))
 			return -EFAULT;
 		return 0;
 	}
 	case VFIO_DEVICE_SET_IRQS:
 	{
 		struct vfio_irq_set hdr;
 		u8 *data = NULL;
 		int ret = 0;
 		size_t data_size = 0;

 		minsz = offsetofend(struct vfio_irq_set, count);

 		if (copy_from_user(&hdr, (void __user *)arg, minsz))
 			return -EFAULT;

 		ret = vfio_set_irqs_validate_and_prepare(&hdr, mc_dev->obj_desc.irq_count,
 					mc_dev->obj_desc.irq_count, &data_size);
 		if (ret)
 			return ret;

 		if (data_size) {
 			data = memdup_user((void __user *)(arg + minsz),
 				   data_size);
 			if (IS_ERR(data))
 				return PTR_ERR(data);
 		}

 		mutex_lock(&vdev->igate);
 		ret = vfio_fsl_mc_set_irqs_ioctl(vdev, hdr.flags,
 						 hdr.index, hdr.start,
 						 hdr.count, data);
 		mutex_unlock(&vdev->igate);
 		kfree(data);

 		return ret;
 	}
 	case VFIO_DEVICE_RESET:
 	{
 		int ret;
 		struct fsl_mc_device *mc_dev = vdev->mc_dev;

 		/* reset is supported only for the DPRC */
 		if (!is_fsl_mc_bus_dprc(mc_dev))
 			return -ENOTTY;

 		ret = dprc_reset_container(mc_dev->mc_io, 0,
 					   mc_dev->mc_handle,
 					   mc_dev->obj_desc.id,
 					   DPRC_RESET_OPTION_NON_RECURSIVE);
 		return ret;

 	}
 	default:
 		return -ENOTTY;
 	}
 }

 static ssize_t vfio_fsl_mc_read(void *device_data, char __user *buf,
 				size_t count, loff_t *ppos)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
 	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	struct vfio_fsl_mc_region *region;
 	u64 data[8];
 	int i;

 	if (index >= mc_dev->obj_desc.region_count)
 		return -EINVAL;

 	region = &vdev->regions[index];

 	if (!(region->flags & VFIO_REGION_INFO_FLAG_READ))
 		return -EINVAL;

 	if (!region->ioaddr) {
 		region->ioaddr = ioremap(region->addr, region->size);
 		if (!region->ioaddr)
 			return -ENOMEM;
 	}

 	if (count != 64 || off != 0)
 		return -EINVAL;

 	for (i = 7; i >= 0; i--)
 		data[i] = readq(region->ioaddr + i * sizeof(uint64_t));

 	if (copy_to_user(buf, data, 64))
 		return -EFAULT;

 	return count;
 }

 #define MC_CMD_COMPLETION_TIMEOUT_MS    5000
 #define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS    500

 static int vfio_fsl_mc_send_command(void __iomem *ioaddr, uint64_t *cmd_data)
 {
 	int i;
 	enum mc_cmd_status status;
 	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;

 	/* Write at command parameter into portal */
 	for (i = 7; i >= 1; i--)
 		writeq_relaxed(cmd_data[i], ioaddr + i * sizeof(uint64_t));

 	/* Write command header in the end */
 	writeq(cmd_data[0], ioaddr);

 	/* Wait for response before returning to user-space
 	 * This can be optimized in future to even prepare response
 	 * before returning to user-space and avoid read ioctl.
 	 */
 	for (;;) {
 		u64 header;
 		struct mc_cmd_header *resp_hdr;

 		header = cpu_to_le64(readq_relaxed(ioaddr));

 		resp_hdr = (struct mc_cmd_header *)&header;
 		status = (enum mc_cmd_status)resp_hdr->status;
 		if (status != MC_CMD_STATUS_READY)
 			break;

 		udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
 		timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
 		if (timeout_usecs == 0)
 			return -ETIMEDOUT;
 	}

 	return 0;
 }

 static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf,
 				 size_t count, loff_t *ppos)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
 	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	struct vfio_fsl_mc_region *region;
 	u64 data[8];
 	int ret;

 	if (index >= mc_dev->obj_desc.region_count)
 		return -EINVAL;

 	region = &vdev->regions[index];

 	if (!(region->flags & VFIO_REGION_INFO_FLAG_WRITE))
 		return -EINVAL;

 	if (!region->ioaddr) {
 		region->ioaddr = ioremap(region->addr, region->size);
 		if (!region->ioaddr)
 			return -ENOMEM;
 	}

 	if (count != 64 || off != 0)
 		return -EINVAL;

 	if (copy_from_user(&data, buf, 64))
 		return -EFAULT;

 	ret = vfio_fsl_mc_send_command(region->ioaddr, data);
 	if (ret)
 		return ret;

 	return count;

 }

 static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region,
 				 struct vm_area_struct *vma)
 {
 	u64 size = vma->vm_end - vma->vm_start;
 	u64 pgoff, base;
 	u8 region_cacheable;

 	pgoff = vma->vm_pgoff &
 		((1U << (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
 	base = pgoff << PAGE_SHIFT;

 	if (region.size < PAGE_SIZE || base + size > region.size)
 		return -EINVAL;

 	region_cacheable = (region.type & FSL_MC_REGION_CACHEABLE) &&
 			   (region.type & FSL_MC_REGION_SHAREABLE);
 	if (!region_cacheable)
 		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

 	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;

 	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 			       size, vma->vm_page_prot);
 }

 static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
 {
 	struct vfio_fsl_mc_device *vdev = device_data;
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	unsigned int index;

 	index = vma->vm_pgoff >> (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT);

 	if (vma->vm_end < vma->vm_start)
 		return -EINVAL;
 	if (vma->vm_start & ~PAGE_MASK)
 		return -EINVAL;
 	if (vma->vm_end & ~PAGE_MASK)
 		return -EINVAL;
 	if (!(vma->vm_flags & VM_SHARED))
 		return -EINVAL;
 	if (index >= mc_dev->obj_desc.region_count)
 		return -EINVAL;

 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
 		return -EINVAL;

 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
 			&& (vma->vm_flags & VM_READ))
 		return -EINVAL;

 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
 			&& (vma->vm_flags & VM_WRITE))
 		return -EINVAL;

 	vma->vm_private_data = mc_dev;

 	return vfio_fsl_mc_mmap_mmio(vdev->regions[index], vma);
 }

 static const struct vfio_device_ops vfio_fsl_mc_ops = {
 	.name		= "vfio-fsl-mc",
 	.open		= vfio_fsl_mc_open,
 	.release	= vfio_fsl_mc_release,
 	.ioctl		= vfio_fsl_mc_ioctl,
 	.read		= vfio_fsl_mc_read,
 	.write		= vfio_fsl_mc_write,
 	.mmap		= vfio_fsl_mc_mmap,
 };

 static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb,
 				    unsigned long action, void *data)
 {
 	struct vfio_fsl_mc_device *vdev = container_of(nb,
 					struct vfio_fsl_mc_device, nb);
 	struct device *dev = data;
 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
 	struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);

 	if (action == BUS_NOTIFY_ADD_DEVICE &&
 	    vdev->mc_dev == mc_cont) {
 		mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s",
 						    vfio_fsl_mc_ops.name);
 		if (!mc_dev->driver_override)
 			dev_warn(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s failed\n",
 				 dev_name(&mc_cont->dev));
 		else
 			dev_info(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s\n",
 				 dev_name(&mc_cont->dev));
 	} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
 		vdev->mc_dev == mc_cont) {
 		struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);

 		if (mc_drv && mc_drv != &vfio_fsl_mc_driver)
 			dev_warn(dev, "VFIO_FSL_MC: Object %s bound to driver %s while DPRC bound to vfio-fsl-mc\n",
 				 dev_name(dev), mc_drv->driver.name);
 	}

 	return 0;
 }

 static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
 {
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	int ret;

 	/* Non-dprc devices share mc_io from parent */
 	if (!is_fsl_mc_bus_dprc(mc_dev)) {
 		struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);

 		mc_dev->mc_io = mc_cont->mc_io;
 		return 0;
 	}

 	vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier;
 	ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb);
 	if (ret)
 		return ret;

 	/* open DPRC, allocate a MC portal */
 	ret = dprc_setup(mc_dev);
 	if (ret) {
 		dev_err(&mc_dev->dev, "VFIO_FSL_MC: Failed to setup DPRC (%d)\n", ret);
 		goto out_nc_unreg;
 	}

 	ret = dprc_scan_container(mc_dev, false);
 	if (ret) {
 		dev_err(&mc_dev->dev, "VFIO_FSL_MC: Container scanning failed (%d)\n", ret);
 		goto out_dprc_cleanup;
 	}

 	return 0;

 out_dprc_cleanup:
 	dprc_remove_devices(mc_dev, NULL, 0);
 	dprc_cleanup(mc_dev);
 out_nc_unreg:
 	bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
 	vdev->nb.notifier_call = NULL;

 	return ret;
 }

 static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 {
 	struct iommu_group *group;
 	struct vfio_fsl_mc_device *vdev;
 	struct device *dev = &mc_dev->dev;
 	int ret;

 	group = vfio_iommu_group_get(dev);
 	if (!group) {
 		dev_err(dev, "VFIO_FSL_MC: No IOMMU group\n");
 		return -EINVAL;
 	}

 	vdev = devm_kzalloc(dev, sizeof(*vdev), GFP_KERNEL);
 	if (!vdev) {
 		ret = -ENOMEM;
 		goto out_group_put;
 	}

 	vdev->mc_dev = mc_dev;

 	ret = vfio_add_group_dev(dev, &vfio_fsl_mc_ops, vdev);
 	if (ret) {
 		dev_err(dev, "VFIO_FSL_MC: Failed to add to vfio group\n");
 		goto out_group_put;
 	}

 	ret = vfio_fsl_mc_reflck_attach(vdev);
 	if (ret)
 		goto out_group_dev;

 	ret = vfio_fsl_mc_init_device(vdev);
 	if (ret)
 		goto out_reflck;

 	mutex_init(&vdev->igate);

 	return 0;

 out_reflck:
 	vfio_fsl_mc_reflck_put(vdev->reflck);
 out_group_dev:
 	vfio_del_group_dev(dev);
 out_group_put:
 	vfio_iommu_group_put(group, dev);
 	return ret;
 }

 static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 {
 	struct vfio_fsl_mc_device *vdev;
 	struct device *dev = &mc_dev->dev;

 	vdev = vfio_del_group_dev(dev);
 	if (!vdev)
 		return -EINVAL;

 	mutex_destroy(&vdev->igate);

 	vfio_fsl_mc_reflck_put(vdev->reflck);

 	if (is_fsl_mc_bus_dprc(mc_dev)) {
 		dprc_remove_devices(mc_dev, NULL, 0);
 		dprc_cleanup(mc_dev);
 	}

 	if (vdev->nb.notifier_call)
 		bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);

 	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);

 	return 0;
 }

 static struct fsl_mc_driver vfio_fsl_mc_driver = {
 	.probe		= vfio_fsl_mc_probe,
 	.remove		= vfio_fsl_mc_remove,
 	.driver	= {
 		.name	= "vfio-fsl-mc",
 		.owner	= THIS_MODULE,
 	},
 };

 static int __init vfio_fsl_mc_driver_init(void)
 {
 	return fsl_mc_driver_register(&vfio_fsl_mc_driver);
 }

 static void __exit vfio_fsl_mc_driver_exit(void)
 {
 	fsl_mc_driver_unregister(&vfio_fsl_mc_driver);
 }

 module_init(vfio_fsl_mc_driver_init);
 module_exit(vfio_fsl_mc_driver_exit);

 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_DESCRIPTION("VFIO for FSL-MC devices - User Level meta-driver");
	// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
	/*
	* Copyright 2013-2016 Freescale Semiconductor Inc.
	* Copyright 2016-2017,2019-2020 NXP
	*/

	#include <linux/device.h>
	#include <linux/iommu.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/slab.h>
	#include <linux/types.h>
	#include <linux/vfio.h>
	#include <linux/fsl/mc.h>
	#include <linux/delay.h>
	#include <linux/io-64-nonatomic-hi-lo.h>

	#include "vfio_fsl_mc_private.h"

	static struct fsl_mc_driver vfio_fsl_mc_driver;

	static DEFINE_MUTEX(reflck_lock);

	static void vfio_fsl_mc_reflck_get(struct vfio_fsl_mc_reflck *reflck)
	{
	kref_get(&reflck->kref);
	}

	static void vfio_fsl_mc_reflck_release(struct kref *kref)
	{
	struct vfio_fsl_mc_reflck *reflck = container_of(kref,
	struct vfio_fsl_mc_reflck,
	kref);

	mutex_destroy(&reflck->lock);
	kfree(reflck);
	mutex_unlock(&reflck_lock);
	}

	static void vfio_fsl_mc_reflck_put(struct vfio_fsl_mc_reflck *reflck)
	{
	kref_put_mutex(&reflck->kref, vfio_fsl_mc_reflck_release, &reflck_lock);
	}

	static struct vfio_fsl_mc_reflck *vfio_fsl_mc_reflck_alloc(void)
	{
	struct vfio_fsl_mc_reflck *reflck;

	reflck = kzalloc(sizeof(*reflck), GFP_KERNEL);
	if (!reflck)
	return ERR_PTR(-ENOMEM);

	kref_init(&reflck->kref);
	mutex_init(&reflck->lock);

	return reflck;
	}

	static int vfio_fsl_mc_reflck_attach(struct vfio_fsl_mc_device *vdev)
	{
	int ret = 0;

	mutex_lock(&reflck_lock);
	if (is_fsl_mc_bus_dprc(vdev->mc_dev)) {
	vdev->reflck = vfio_fsl_mc_reflck_alloc();
	ret = PTR_ERR_OR_ZERO(vdev->reflck);
	} else {
	struct device *mc_cont_dev = vdev->mc_dev->dev.parent;
	struct vfio_device *device;
	struct vfio_fsl_mc_device *cont_vdev;

	device = vfio_device_get_from_dev(mc_cont_dev);
	if (!device) {
	ret = -ENODEV;
	goto unlock;
	}

	cont_vdev = vfio_device_data(device);
	if (!cont_vdev \|\| !cont_vdev->reflck) {
	vfio_device_put(device);
	ret = -ENODEV;
	goto unlock;
	}
	vfio_fsl_mc_reflck_get(cont_vdev->reflck);
	vdev->reflck = cont_vdev->reflck;
	vfio_device_put(device);
	}

	unlock:
	mutex_unlock(&reflck_lock);
	return ret;
	}

	static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev)
	{
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	int count = mc_dev->obj_desc.region_count;
	int i;

	vdev->regions = kcalloc(count, sizeof(struct vfio_fsl_mc_region),
	GFP_KERNEL);
	if (!vdev->regions)
	return -ENOMEM;

	for (i = 0; i < count; i++) {
	struct resource *res = &mc_dev->regions[i];
	int no_mmap = is_fsl_mc_bus_dprc(mc_dev);

	vdev->regions[i].addr = res->start;
	vdev->regions[i].size = resource_size(res);
	vdev->regions[i].type = mc_dev->regions[i].flags & IORESOURCE_BITS;
	/*
	* Only regions addressed with PAGE granularity may be
	* MMAPed securely.
	*/
	if (!no_mmap && !(vdev->regions[i].addr & ~PAGE_MASK) &&
	!(vdev->regions[i].size & ~PAGE_MASK))
	vdev->regions[i].flags \|=
	VFIO_REGION_INFO_FLAG_MMAP;
	vdev->regions[i].flags \|= VFIO_REGION_INFO_FLAG_READ;
	if (!(mc_dev->regions[i].flags & IORESOURCE_READONLY))
	vdev->regions[i].flags \|= VFIO_REGION_INFO_FLAG_WRITE;
	}

	return 0;
	}

	static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
	{
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	int i;

	for (i = 0; i < mc_dev->obj_desc.region_count; i++)
	iounmap(vdev->regions[i].ioaddr);
	kfree(vdev->regions);
	}

	static int vfio_fsl_mc_open(void *device_data)
	{
	struct vfio_fsl_mc_device *vdev = device_data;
	int ret;

	if (!try_module_get(THIS_MODULE))
	return -ENODEV;

	mutex_lock(&vdev->reflck->lock);
	if (!vdev->refcnt) {
	ret = vfio_fsl_mc_regions_init(vdev);
	if (ret)
	goto err_reg_init;
	}
	vdev->refcnt++;

	mutex_unlock(&vdev->reflck->lock);

	return 0;

	err_reg_init:
	mutex_unlock(&vdev->reflck->lock);
	module_put(THIS_MODULE);
	return ret;
	}

	static void vfio_fsl_mc_release(void *device_data)
	{
	struct vfio_fsl_mc_device *vdev = device_data;
	int ret;

	mutex_lock(&vdev->reflck->lock);

	if (!(--vdev->refcnt)) {
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
	struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);

	vfio_fsl_mc_regions_cleanup(vdev);

	/* reset the device before cleaning up the interrupts */
	ret = dprc_reset_container(mc_cont->mc_io, 0,
	mc_cont->mc_handle,
	mc_cont->obj_desc.id,
	DPRC_RESET_OPTION_NON_RECURSIVE);

	if (ret) {
	dev_warn(&mc_cont->dev, "VFIO_FLS_MC: reset device has failed (%d)\n",
	ret);
	WARN_ON(1);
	}

	vfio_fsl_mc_irqs_cleanup(vdev);

	fsl_mc_cleanup_irq_pool(mc_cont);
	}

	mutex_unlock(&vdev->reflck->lock);

	module_put(THIS_MODULE);
	}

	static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
	unsigned long arg)
	{
	unsigned long minsz;
	struct vfio_fsl_mc_device *vdev = device_data;
	struct fsl_mc_device *mc_dev = vdev->mc_dev;

	switch (cmd) {
	case VFIO_DEVICE_GET_INFO:
	{
	struct vfio_device_info info;

	minsz = offsetofend(struct vfio_device_info, num_irqs);

	if (copy_from_user(&info, (void __user *)arg, minsz))
	return -EFAULT;

	if (info.argsz < minsz)
	return -EINVAL;

	info.flags = VFIO_DEVICE_FLAGS_FSL_MC;

	if (is_fsl_mc_bus_dprc(mc_dev))
	info.flags \|= VFIO_DEVICE_FLAGS_RESET;

	info.num_regions = mc_dev->obj_desc.region_count;
	info.num_irqs = mc_dev->obj_desc.irq_count;

	return copy_to_user((void __user *)arg, &info, minsz) ?
	-EFAULT : 0;
	}
	case VFIO_DEVICE_GET_REGION_INFO:
	{
	struct vfio_region_info info;

	minsz = offsetofend(struct vfio_region_info, offset);

	if (copy_from_user(&info, (void __user *)arg, minsz))
	return -EFAULT;

	if (info.argsz < minsz)
	return -EINVAL;

	if (info.index >= mc_dev->obj_desc.region_count)
	return -EINVAL;

	/* map offset to the physical address */
	info.offset = VFIO_FSL_MC_INDEX_TO_OFFSET(info.index);
	info.size = vdev->regions[info.index].size;
	info.flags = vdev->regions[info.index].flags;

	if (copy_to_user((void __user *)arg, &info, minsz))
	return -EFAULT;
	return 0;
	}
	case VFIO_DEVICE_GET_IRQ_INFO:
	{
	struct vfio_irq_info info;

	minsz = offsetofend(struct vfio_irq_info, count);
	if (copy_from_user(&info, (void __user *)arg, minsz))
	return -EFAULT;

	if (info.argsz < minsz)
	return -EINVAL;

	if (info.index >= mc_dev->obj_desc.irq_count)
	return -EINVAL;

	info.flags = VFIO_IRQ_INFO_EVENTFD;
	info.count = 1;

	if (copy_to_user((void __user *)arg, &info, minsz))
	return -EFAULT;
	return 0;
	}
	case VFIO_DEVICE_SET_IRQS:
	{
	struct vfio_irq_set hdr;
	u8 *data = NULL;
	int ret = 0;
	size_t data_size = 0;

	minsz = offsetofend(struct vfio_irq_set, count);

	if (copy_from_user(&hdr, (void __user *)arg, minsz))
	return -EFAULT;

	ret = vfio_set_irqs_validate_and_prepare(&hdr, mc_dev->obj_desc.irq_count,
	mc_dev->obj_desc.irq_count, &data_size);
	if (ret)
	return ret;

	if (data_size) {
	data = memdup_user((void __user *)(arg + minsz),
	data_size);
	if (IS_ERR(data))
	return PTR_ERR(data);
	}

	mutex_lock(&vdev->igate);
	ret = vfio_fsl_mc_set_irqs_ioctl(vdev, hdr.flags,
	hdr.index, hdr.start,
	hdr.count, data);
	mutex_unlock(&vdev->igate);
	kfree(data);

	return ret;
	}
	case VFIO_DEVICE_RESET:
	{
	int ret;
	struct fsl_mc_device *mc_dev = vdev->mc_dev;

	/* reset is supported only for the DPRC */
	if (!is_fsl_mc_bus_dprc(mc_dev))
	return -ENOTTY;

	ret = dprc_reset_container(mc_dev->mc_io, 0,
	mc_dev->mc_handle,
	mc_dev->obj_desc.id,
	DPRC_RESET_OPTION_NON_RECURSIVE);
	return ret;

	}
	default:
	return -ENOTTY;
	}
	}

	static ssize_t vfio_fsl_mc_read(void device_data, char __user buf,
	size_t count, loff_t *ppos)
	{
	struct vfio_fsl_mc_device *vdev = device_data;
	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	struct vfio_fsl_mc_region *region;
	u64 data[8];
	int i;

	if (index >= mc_dev->obj_desc.region_count)
	return -EINVAL;

	region = &vdev->regions[index];

	if (!(region->flags & VFIO_REGION_INFO_FLAG_READ))
	return -EINVAL;

	if (!region->ioaddr) {
	region->ioaddr = ioremap(region->addr, region->size);
	if (!region->ioaddr)
	return -ENOMEM;
	}

	if (count != 64 \|\| off != 0)
	return -EINVAL;

	for (i = 7; i >= 0; i--)
	data[i] = readq(region->ioaddr + i * sizeof(uint64_t));

	if (copy_to_user(buf, data, 64))
	return -EFAULT;

	return count;
	}

	#define MC_CMD_COMPLETION_TIMEOUT_MS 5000
	#define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS 500

	static int vfio_fsl_mc_send_command(void __iomem ioaddr, uint64_t cmd_data)
	{
	int i;
	enum mc_cmd_status status;
	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;

	/* Write at command parameter into portal */
	for (i = 7; i >= 1; i--)
	writeq_relaxed(cmd_data[i], ioaddr + i * sizeof(uint64_t));

	/* Write command header in the end */
	writeq(cmd_data[0], ioaddr);

	/* Wait for response before returning to user-space
	* This can be optimized in future to even prepare response
	* before returning to user-space and avoid read ioctl.
	*/
	for (;;) {
	u64 header;
	struct mc_cmd_header *resp_hdr;

	header = cpu_to_le64(readq_relaxed(ioaddr));

	resp_hdr = (struct mc_cmd_header *)&header;
	status = (enum mc_cmd_status)resp_hdr->status;
	if (status != MC_CMD_STATUS_READY)
	break;

	udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
	timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
	if (timeout_usecs == 0)
	return -ETIMEDOUT;
	}

	return 0;
	}

	static ssize_t vfio_fsl_mc_write(void device_data, const char __user buf,
	size_t count, loff_t *ppos)
	{
	struct vfio_fsl_mc_device *vdev = device_data;
	unsigned int index = VFIO_FSL_MC_OFFSET_TO_INDEX(*ppos);
	loff_t off = *ppos & VFIO_FSL_MC_OFFSET_MASK;
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	struct vfio_fsl_mc_region *region;
	u64 data[8];
	int ret;

	if (index >= mc_dev->obj_desc.region_count)
	return -EINVAL;

	region = &vdev->regions[index];

	if (!(region->flags & VFIO_REGION_INFO_FLAG_WRITE))
	return -EINVAL;

	if (!region->ioaddr) {
	region->ioaddr = ioremap(region->addr, region->size);
	if (!region->ioaddr)
	return -ENOMEM;
	}

	if (count != 64 \|\| off != 0)
	return -EINVAL;

	if (copy_from_user(&data, buf, 64))
	return -EFAULT;

	ret = vfio_fsl_mc_send_command(region->ioaddr, data);
	if (ret)
	return ret;

	return count;

	}

	static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region,
	struct vm_area_struct *vma)
	{
	u64 size = vma->vm_end - vma->vm_start;
	u64 pgoff, base;
	u8 region_cacheable;

	pgoff = vma->vm_pgoff &
	((1U << (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
	base = pgoff << PAGE_SHIFT;

	if (region.size < PAGE_SIZE \|\| base + size > region.size)
	return -EINVAL;

	region_cacheable = (region.type & FSL_MC_REGION_CACHEABLE) &&
	(region.type & FSL_MC_REGION_SHAREABLE);
	if (!region_cacheable)
	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;

	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
	size, vma->vm_page_prot);
	}

	static int vfio_fsl_mc_mmap(void device_data, struct vm_area_struct vma)
	{
	struct vfio_fsl_mc_device *vdev = device_data;
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	unsigned int index;

	index = vma->vm_pgoff >> (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT);

	if (vma->vm_end < vma->vm_start)
	return -EINVAL;
	if (vma->vm_start & ~PAGE_MASK)
	return -EINVAL;
	if (vma->vm_end & ~PAGE_MASK)
	return -EINVAL;
	if (!(vma->vm_flags & VM_SHARED))
	return -EINVAL;
	if (index >= mc_dev->obj_desc.region_count)
	return -EINVAL;

	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
	return -EINVAL;

	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
	&& (vma->vm_flags & VM_READ))
	return -EINVAL;

	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
	&& (vma->vm_flags & VM_WRITE))
	return -EINVAL;

	vma->vm_private_data = mc_dev;

	return vfio_fsl_mc_mmap_mmio(vdev->regions[index], vma);
	}

	static const struct vfio_device_ops vfio_fsl_mc_ops = {
	.name = "vfio-fsl-mc",
	.open = vfio_fsl_mc_open,
	.release = vfio_fsl_mc_release,
	.ioctl = vfio_fsl_mc_ioctl,
	.read = vfio_fsl_mc_read,
	.write = vfio_fsl_mc_write,
	.mmap = vfio_fsl_mc_mmap,
	};

	static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb,
	unsigned long action, void *data)
	{
	struct vfio_fsl_mc_device *vdev = container_of(nb,
	struct vfio_fsl_mc_device, nb);
	struct device *dev = data;
	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
	struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);

	if (action == BUS_NOTIFY_ADD_DEVICE &&
	vdev->mc_dev == mc_cont) {
	mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s",
	vfio_fsl_mc_ops.name);
	if (!mc_dev->driver_override)
	dev_warn(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s failed\n",
	dev_name(&mc_cont->dev));
	else
	dev_info(dev, "VFIO_FSL_MC: Setting driver override for device in dprc %s\n",
	dev_name(&mc_cont->dev));
	} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
	vdev->mc_dev == mc_cont) {
	struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);

	if (mc_drv && mc_drv != &vfio_fsl_mc_driver)
	dev_warn(dev, "VFIO_FSL_MC: Object %s bound to driver %s while DPRC bound to vfio-fsl-mc\n",
	dev_name(dev), mc_drv->driver.name);
	}

	return 0;
	}

	static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev)
	{
	struct fsl_mc_device *mc_dev = vdev->mc_dev;
	int ret;

	/* Non-dprc devices share mc_io from parent */
	if (!is_fsl_mc_bus_dprc(mc_dev)) {
	struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent);

	mc_dev->mc_io = mc_cont->mc_io;
	return 0;
	}

	vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier;
	ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb);
	if (ret)
	return ret;

	/* open DPRC, allocate a MC portal */
	ret = dprc_setup(mc_dev);
	if (ret) {
	dev_err(&mc_dev->dev, "VFIO_FSL_MC: Failed to setup DPRC (%d)\n", ret);
	goto out_nc_unreg;
	}

	ret = dprc_scan_container(mc_dev, false);
	if (ret) {
	dev_err(&mc_dev->dev, "VFIO_FSL_MC: Container scanning failed (%d)\n", ret);
	goto out_dprc_cleanup;
	}

	return 0;

	out_dprc_cleanup:
	dprc_remove_devices(mc_dev, NULL, 0);
	dprc_cleanup(mc_dev);
	out_nc_unreg:
	bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);
	vdev->nb.notifier_call = NULL;

	return ret;
	}

	static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
	{
	struct iommu_group *group;
	struct vfio_fsl_mc_device *vdev;
	struct device *dev = &mc_dev->dev;
	int ret;

	group = vfio_iommu_group_get(dev);
	if (!group) {
	dev_err(dev, "VFIO_FSL_MC: No IOMMU group\n");
	return -EINVAL;
	}

	vdev = devm_kzalloc(dev, sizeof(*vdev), GFP_KERNEL);
	if (!vdev) {
	ret = -ENOMEM;
	goto out_group_put;
	}

	vdev->mc_dev = mc_dev;

	ret = vfio_add_group_dev(dev, &vfio_fsl_mc_ops, vdev);
	if (ret) {
	dev_err(dev, "VFIO_FSL_MC: Failed to add to vfio group\n");
	goto out_group_put;
	}

	ret = vfio_fsl_mc_reflck_attach(vdev);
	if (ret)
	goto out_group_dev;

	ret = vfio_fsl_mc_init_device(vdev);
	if (ret)
	goto out_reflck;

	mutex_init(&vdev->igate);

	return 0;

	out_reflck:
	vfio_fsl_mc_reflck_put(vdev->reflck);
	out_group_dev:
	vfio_del_group_dev(dev);
	out_group_put:
	vfio_iommu_group_put(group, dev);
	return ret;
	}

	static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
	{
	struct vfio_fsl_mc_device *vdev;
	struct device *dev = &mc_dev->dev;

	vdev = vfio_del_group_dev(dev);
	if (!vdev)
	return -EINVAL;

	mutex_destroy(&vdev->igate);

	vfio_fsl_mc_reflck_put(vdev->reflck);

	if (is_fsl_mc_bus_dprc(mc_dev)) {
	dprc_remove_devices(mc_dev, NULL, 0);
	dprc_cleanup(mc_dev);
	}

	if (vdev->nb.notifier_call)
	bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb);

	vfio_iommu_group_put(mc_dev->dev.iommu_group, dev);

	return 0;
	}

	static struct fsl_mc_driver vfio_fsl_mc_driver = {
	.probe = vfio_fsl_mc_probe,
	.remove = vfio_fsl_mc_remove,
	.driver = {
	.name = "vfio-fsl-mc",
	.owner = THIS_MODULE,
	},
	};

	static int __init vfio_fsl_mc_driver_init(void)
	{
	return fsl_mc_driver_register(&vfio_fsl_mc_driver);
	}

	static void __exit vfio_fsl_mc_driver_exit(void)
	{
	fsl_mc_driver_unregister(&vfio_fsl_mc_driver);
	}

	module_init(vfio_fsl_mc_driver_init);
	module_exit(vfio_fsl_mc_driver_exit);

	MODULE_LICENSE("Dual BSD/GPL");
	MODULE_DESCRIPTION("VFIO for FSL-MC devices - User Level meta-driver");