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>

1 files changed, 29 insertions, 18 deletions

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;