vfio: Make vfio_device_ops pass a 'struct vfio_device *' instead of 'void *'

This is the standard kernel pattern, the ops associated with a struct get
the struct pointer in for typesafety. The expected design is to use
container_of to cleanly go from the subsystem level type to the driver
level type without having any type erasure in a void *.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <12-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

5 files changed, 99 insertions, 70 deletions

diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index ad6c6feeeb4b..45f397c04a89 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -135,9 +135,10 @@ static void vfio_fsl_mc_regions_cleanup(struct vfio_fsl_mc_device *vdev)
 	kfree(vdev->regions);
 }
 
-static int vfio_fsl_mc_open(void *device_data)
+static int vfio_fsl_mc_open(struct vfio_device *core_vdev)
 {
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	int ret;
 
 	if (!try_module_get(THIS_MODULE))
@@ -161,9 +162,10 @@ err_reg_init:
 	return ret;
 }
 
-static void vfio_fsl_mc_release(void *device_data)
+static void vfio_fsl_mc_release(struct vfio_device *core_vdev)
 {
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	int ret;
 
 	mutex_lock(&vdev->reflck->lock);
@@ -197,11 +199,12 @@ static void vfio_fsl_mc_release(void *device_data)
 	module_put(THIS_MODULE);
 }
 
-static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
-			      unsigned long arg)
+static long vfio_fsl_mc_ioctl(struct vfio_device *core_vdev,
+			      unsigned int cmd, unsigned long arg)
 {
 	unsigned long minsz;
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 
 	switch (cmd) {
@@ -327,10 +330,11 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 	}
 }
 
-static ssize_t vfio_fsl_mc_read(void *device_data, char __user *buf,
+static ssize_t vfio_fsl_mc_read(struct vfio_device *core_vdev, char __user *buf,
 				size_t count, loff_t *ppos)
 {
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	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;
@@ -404,10 +408,12 @@ static int vfio_fsl_mc_send_command(void __iomem *ioaddr, uint64_t *cmd_data)
 	return 0;
 }
 
-static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf,
-				 size_t count, loff_t *ppos)
+static ssize_t vfio_fsl_mc_write(struct vfio_device *core_vdev,
+				 const char __user *buf, size_t count,
+				 loff_t *ppos)
 {
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	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;
@@ -468,9 +474,11 @@ static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region,
 			       size, vma->vm_page_prot);
 }
 
-static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma)
+static int vfio_fsl_mc_mmap(struct vfio_device *core_vdev,
+			    struct vm_area_struct *vma)
 {
-	struct vfio_fsl_mc_device *vdev = device_data;
+	struct vfio_fsl_mc_device *vdev =
+		container_of(core_vdev, struct vfio_fsl_mc_device, vdev);
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	unsigned int index;
 
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
index 4043cc91f952..11b3e15403ba 100644
--- a/drivers/vfio/mdev/vfio_mdev.c
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -21,10 +21,11 @@
 #define DRIVER_AUTHOR   "NVIDIA Corporation"
 #define DRIVER_DESC     "VFIO based driver for Mediated device"
 
-static int vfio_mdev_open(void *device_data)
+static int vfio_mdev_open(struct vfio_device *core_vdev)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
+
 	int ret;
 
 	if (unlikely(!parent->ops->open))
@@ -40,9 +41,9 @@ static int vfio_mdev_open(void *device_data)
 	return ret;
 }
 
-static void vfio_mdev_release(void *device_data)
+static void vfio_mdev_release(struct vfio_device *core_vdev)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (likely(parent->ops->release))
@@ -51,10 +52,10 @@ static void vfio_mdev_release(void *device_data)
 	module_put(THIS_MODULE);
 }
 
-static long vfio_mdev_unlocked_ioctl(void *device_data,
+static long vfio_mdev_unlocked_ioctl(struct vfio_device *core_vdev,
 				     unsigned int cmd, unsigned long arg)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (unlikely(!parent->ops->ioctl))
@@ -63,10 +64,10 @@ static long vfio_mdev_unlocked_ioctl(void *device_data,
 	return parent->ops->ioctl(mdev, cmd, arg);
 }
 
-static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
+static ssize_t vfio_mdev_read(struct vfio_device *core_vdev, char __user *buf,
 			      size_t count, loff_t *ppos)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (unlikely(!parent->ops->read))
@@ -75,10 +76,11 @@ static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
 	return parent->ops->read(mdev, buf, count, ppos);
 }
 
-static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
-			       size_t count, loff_t *ppos)
+static ssize_t vfio_mdev_write(struct vfio_device *core_vdev,
+			       const char __user *buf, size_t count,
+			       loff_t *ppos)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (unlikely(!parent->ops->write))
@@ -87,9 +89,10 @@ static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
 	return parent->ops->write(mdev, buf, count, ppos);
 }
 
-static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
+static int vfio_mdev_mmap(struct vfio_device *core_vdev,
+			  struct vm_area_struct *vma)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (unlikely(!parent->ops->mmap))
@@ -98,9 +101,9 @@ static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
 	return parent->ops->mmap(mdev, vma);
 }
 
-static void vfio_mdev_request(void *device_data, unsigned int count)
+static void vfio_mdev_request(struct vfio_device *core_vdev, unsigned int count)
 {
-	struct mdev_device *mdev = device_data;
+	struct mdev_device *mdev = to_mdev_device(core_vdev->dev);
 	struct mdev_parent *parent = mdev->parent;
 
 	if (parent->ops->request)
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index a0ac20a499cf..5f1a782d1c65 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -553,9 +553,10 @@ static void vfio_pci_vf_token_user_add(struct vfio_pci_device *vdev, int val)
 	vfio_device_put(pf_dev);
 }
 
-static void vfio_pci_release(void *device_data)
+static void vfio_pci_release(struct vfio_device *core_vdev)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 
 	mutex_lock(&vdev->reflck->lock);
 
@@ -581,9 +582,10 @@ static void vfio_pci_release(void *device_data)
 	module_put(THIS_MODULE);
 }
 
-static int vfio_pci_open(void *device_data)
+static int vfio_pci_open(struct vfio_device *core_vdev)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 	int ret = 0;
 
 	if (!try_module_get(THIS_MODULE))
@@ -797,10 +799,11 @@ struct vfio_devices {
 	int max_index;
 };
 
-static long vfio_pci_ioctl(void *device_data,
+static long vfio_pci_ioctl(struct vfio_device *core_vdev,
 			   unsigned int cmd, unsigned long arg)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 	unsigned long minsz;
 
 	if (cmd == VFIO_DEVICE_GET_INFO) {
@@ -1402,11 +1405,10 @@ hot_reset_release:
 	return -ENOTTY;
 }
 
-static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
+static ssize_t vfio_pci_rw(struct vfio_pci_device *vdev, char __user *buf,
 			   size_t count, loff_t *ppos, bool iswrite)
 {
 	unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos);
-	struct vfio_pci_device *vdev = device_data;
 
 	if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions)
 		return -EINVAL;
@@ -1434,22 +1436,28 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf,
 	return -EINVAL;
 }
 
-static ssize_t vfio_pci_read(void *device_data, char __user *buf,
+static ssize_t vfio_pci_read(struct vfio_device *core_vdev, char __user *buf,
 			     size_t count, loff_t *ppos)
 {
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
+
 	if (!count)
 		return 0;
 
-	return vfio_pci_rw(device_data, buf, count, ppos, false);
+	return vfio_pci_rw(vdev, buf, count, ppos, false);
 }
 
-static ssize_t vfio_pci_write(void *device_data, const char __user *buf,
+static ssize_t vfio_pci_write(struct vfio_device *core_vdev, const char __user *buf,
 			      size_t count, loff_t *ppos)
 {
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
+
 	if (!count)
 		return 0;
 
-	return vfio_pci_rw(device_data, (char __user *)buf, count, ppos, true);
+	return vfio_pci_rw(vdev, (char __user *)buf, count, ppos, true);
 }
 
 /* Return 1 on zap and vma_lock acquired, 0 on contention (only with @try) */
@@ -1646,9 +1654,10 @@ static const struct vm_operations_struct vfio_pci_mmap_ops = {
 	.fault = vfio_pci_mmap_fault,
 };
 
-static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
+static int vfio_pci_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 	struct pci_dev *pdev = vdev->pdev;
 	unsigned int index;
 	u64 phys_len, req_len, pgoff, req_start;
@@ -1714,9 +1723,10 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma)
 	return 0;
 }
 
-static void vfio_pci_request(void *device_data, unsigned int count)
+static void vfio_pci_request(struct vfio_device *core_vdev, unsigned int count)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 	struct pci_dev *pdev = vdev->pdev;
 
 	mutex_lock(&vdev->igate);
@@ -1830,9 +1840,10 @@ static int vfio_pci_validate_vf_token(struct vfio_pci_device *vdev,
 
 #define VF_TOKEN_ARG "vf_token="
 
-static int vfio_pci_match(void *device_data, char *buf)
+static int vfio_pci_match(struct vfio_device *core_vdev, char *buf)
 {
-	struct vfio_pci_device *vdev = device_data;
+	struct vfio_pci_device *vdev =
+		container_of(core_vdev, struct vfio_pci_device, vdev);
 	bool vf_token = false;
 	uuid_t uuid;
 	int ret;
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 6eb749250ee4..f5f6b537084a 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -218,9 +218,10 @@ static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
 	return -EINVAL;
 }
 
-static void vfio_platform_release(void *device_data)
+static void vfio_platform_release(struct vfio_device *core_vdev)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
 
 	mutex_lock(&driver_lock);
 
@@ -244,9 +245,10 @@ static void vfio_platform_release(void *device_data)
 	module_put(vdev->parent_module);
 }
 
-static int vfio_platform_open(void *device_data)
+static int vfio_platform_open(struct vfio_device *core_vdev)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
 	int ret;
 
 	if (!try_module_get(vdev->parent_module))
@@ -293,10 +295,12 @@ err_reg:
 	return ret;
 }
 
-static long vfio_platform_ioctl(void *device_data,
+static long vfio_platform_ioctl(struct vfio_device *core_vdev,
 				unsigned int cmd, unsigned long arg)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
+
 	unsigned long minsz;
 
 	if (cmd == VFIO_DEVICE_GET_INFO) {
@@ -455,10 +459,11 @@ err:
 	return -EFAULT;
 }
 
-static ssize_t vfio_platform_read(void *device_data, char __user *buf,
-				  size_t count, loff_t *ppos)
+static ssize_t vfio_platform_read(struct vfio_device *core_vdev,
+				  char __user *buf, size_t count, loff_t *ppos)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
 	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 
@@ -531,10 +536,11 @@ err:
 	return -EFAULT;
 }
 
-static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
+static ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
 				   size_t count, loff_t *ppos)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
 	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
 	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
 
@@ -573,9 +579,10 @@ static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
 			       req_len, vma->vm_page_prot);
 }
 
-static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
+static int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
 {
-	struct vfio_platform_device *vdev = device_data;
+	struct vfio_platform_device *vdev =
+		container_of(core_vdev, struct vfio_platform_device, vdev);
 	unsigned int index;
 
 	index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 180b4ab02d11..e6f5109fba48 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -832,7 +832,7 @@ static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group,
 		int ret;
 
 		if (it->ops->match) {
-			ret = it->ops->match(it->device_data, buf);
+			ret = it->ops->match(it, buf);
 			if (ret < 0) {
 				device = ERR_PTR(ret);
 				break;
@@ -893,7 +893,7 @@ void vfio_unregister_group_dev(struct vfio_device *device)
 	rc = try_wait_for_completion(&device->comp);
 	while (rc <= 0) {
 		if (device->ops->request)
-			device->ops->request(device->device_data, i++);
+			device->ops->request(device, i++);
 
 		if (interrupted) {
 			rc = wait_for_completion_timeout(&device->comp,
@@ -1379,7 +1379,7 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
 	if (IS_ERR(device))
 		return PTR_ERR(device);
 
-	ret = device->ops->open(device->device_data);
+	ret = device->ops->open(device);
 	if (ret) {
 		vfio_device_put(device);
 		return ret;
@@ -1391,7 +1391,7 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
 	 */
 	ret = get_unused_fd_flags(O_CLOEXEC);
 	if (ret < 0) {
-		device->ops->release(device->device_data);
+		device->ops->release(device);
 		vfio_device_put(device);
 		return ret;
 	}
@@ -1401,7 +1401,7 @@ static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
 	if (IS_ERR(filep)) {
 		put_unused_fd(ret);
 		ret = PTR_ERR(filep);
-		device->ops->release(device->device_data);
+		device->ops->release(device);
 		vfio_device_put(device);
 		return ret;
 	}
@@ -1558,7 +1558,7 @@ static int vfio_device_fops_release(struct inode *inode, struct file *filep)
 {
 	struct vfio_device *device = filep->private_data;
 
-	device->ops->release(device->device_data);
+	device->ops->release(device);
 
 	vfio_group_try_dissolve_container(device->group);
 
@@ -1575,7 +1575,7 @@ static long vfio_device_fops_unl_ioctl(struct file *filep,
 	if (unlikely(!device->ops->ioctl))
 		return -EINVAL;
 
-	return device->ops->ioctl(device->device_data, cmd, arg);
+	return device->ops->ioctl(device, cmd, arg);
 }
 
 static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf,
@@ -1586,7 +1586,7 @@ static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf,
 	if (unlikely(!device->ops->read))
 		return -EINVAL;
 
-	return device->ops->read(device->device_data, buf, count, ppos);
+	return device->ops->read(device, buf, count, ppos);
 }
 
 static ssize_t vfio_device_fops_write(struct file *filep,
@@ -1598,7 +1598,7 @@ static ssize_t vfio_device_fops_write(struct file *filep,
 	if (unlikely(!device->ops->write))
 		return -EINVAL;
 
-	return device->ops->write(device->device_data, buf, count, ppos);
+	return device->ops->write(device, buf, count, ppos);
 }
 
 static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
@@ -1608,7 +1608,7 @@ static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
 	if (unlikely(!device->ops->mmap))
 		return -EINVAL;
 
-	return device->ops->mmap(device->device_data, vma);
+	return device->ops->mmap(device, vma);
 }
 
 static const struct file_operations vfio_device_fops = {