[Intel-gfx] [PATCH 09/10] vfio/mdpy: Convert to use vfio_register_group_dev()

Christoph Hellwig
2021-06-15T13:43:20Z

From: Jason Gunthorpe <jgg@nvidia.com>

This is straightforward conversion, the mdev_state is actually serving as
the vfio_device and we can replace all the mdev_get_drvdata()'s and the
wonky dead code with a simple container_of().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
samples/vfio-mdev/mdpy.c | 159 ++++++++++++++++++++++-----------------
1 file changed, 88 insertions(+), 71 deletions(-)

diff --git a/samples/vfio-mdev/mdpy.c b/samples/vfio-mdev/mdpy.c
index e889c1cf8fd1..7e9c9df0f05b 100644
--- a/samples/vfio-mdev/mdpy.c
+++ b/samples/vfio-mdev/mdpy.c
@@ -85,9 +85,11 @@ static struct class *mdpy_class;
static struct cdev mdpy_cdev;
static struct device mdpy_dev;
static u32 mdpy_count;
+static const struct vfio_device_ops mdpy_dev_ops;

/* State of each mdev device */
struct mdev_state {
+ struct vfio_device vdev;
u8 *vconfig;
u32 bar_mask;
struct mutex ops_lock;
@@ -162,11 +164,9 @@ static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
}
}

-static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
- loff_t pos, bool is_write)
+static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
+ size_t count, loff_t pos, bool is_write)
{
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
- struct device *dev = mdev_dev(mdev);
int ret = 0;

mutex_lock(&mdev_state->ops_lock);
@@ -187,8 +187,9 @@ static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
memcpy(buf, mdev_state->memblk, count);

} else {
- dev_info(dev, "%s: %s @0x%llx (unhandled)\n",
- __func__, is_write ? "WR" : "RD", pos);
+ dev_info(mdev_state->vdev.dev,
+ "%s: %s @0x%llx (unhandled)\n", __func__,
+ is_write ? "WR" : "RD", pos);
ret = -1;
goto accessfailed;
}
@@ -202,9 +203,8 @@ static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
return ret;
}

-static int mdpy_reset(struct mdev_device *mdev)
+static int mdpy_reset(struct mdev_state *mdev_state)
{
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
u32 stride, i;

/* initialize with gray gradient */
@@ -216,13 +216,14 @@ static int mdpy_reset(struct mdev_device *mdev)
return 0;
}

-static int mdpy_create(struct mdev_device *mdev)
+static int mdpy_probe(struct mdev_device *mdev)
{
const struct mdpy_type *type =
&mdpy_types[mdev_get_type_group_id(mdev)];
struct device *dev = mdev_dev(mdev);
struct mdev_state *mdev_state;
u32 fbsize;
+ int ret;

if (mdpy_count >= max_devices)
return -ENOMEM;
@@ -230,6 +231,7 @@ static int mdpy_create(struct mdev_device *mdev)
mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
if (mdev_state == NULL)
return -ENOMEM;
+ vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mdpy_dev_ops);

mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL);
if (mdev_state->vconfig == NULL) {
@@ -250,36 +252,41 @@ static int mdpy_create(struct mdev_device *mdev)

mutex_init(&mdev_state->ops_lock);
mdev_state->mdev = mdev;
- mdev_set_drvdata(mdev, mdev_state);
-
mdev_state->type = type;
mdev_state->memsize = fbsize;
mdpy_create_config_space(mdev_state);
- mdpy_reset(mdev);
+ mdpy_reset(mdev_state);

mdpy_count++;
+
+ ret = vfio_register_group_dev(&mdev_state->vdev);
+ if (ret) {
+ kfree(mdev_state);
+ return ret;
+ }
+ dev_set_drvdata(&mdev->dev, mdev_state);
return 0;
}

-static int mdpy_remove(struct mdev_device *mdev)
+static void mdpy_remove(struct mdev_device *mdev)
{
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
- struct device *dev = mdev_dev(mdev);
+ struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);

- dev_info(dev, "%s\n", __func__);
+ dev_info(&mdev->dev, "%s\n", __func__);

- mdev_set_drvdata(mdev, NULL);
+ vfio_unregister_group_dev(&mdev_state->vdev);
vfree(mdev_state->memblk);
kfree(mdev_state->vconfig);
kfree(mdev_state);

mdpy_count--;
- return 0;
}

-static ssize_t mdpy_read(struct mdev_device *mdev, char __user *buf,
+static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf,
size_t count, loff_t *ppos)
{
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);
unsigned int done = 0;
int ret;

@@ -289,8 +296,8 @@ static ssize_t mdpy_read(struct mdev_device *mdev, char __user *buf,
if (count >= 4 && !(*ppos % 4)) {
u32 val;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
- *ppos, false);
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
+ *ppos, false);
if (ret <= 0)
goto read_err;

@@ -301,7 +308,7 @@ static ssize_t mdpy_read(struct mdev_device *mdev, char __user *buf,
} else if (count >= 2 && !(*ppos % 2)) {
u16 val;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, false);
if (ret <= 0)
goto read_err;
@@ -313,7 +320,7 @@ static ssize_t mdpy_read(struct mdev_device *mdev, char __user *buf,
} else {
u8 val;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, false);
if (ret <= 0)
goto read_err;
@@ -336,9 +343,11 @@ static ssize_t mdpy_read(struct mdev_device *mdev, char __user *buf,
return -EFAULT;
}

-static ssize_t mdpy_write(struct mdev_device *mdev, const char __user *buf,
+static ssize_t mdpy_write(struct vfio_device *vdev, const char __user *buf,
size_t count, loff_t *ppos)
{
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);
unsigned int done = 0;
int ret;

@@ -351,7 +360,7 @@ static ssize_t mdpy_write(struct mdev_device *mdev, const char __user *buf,
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
@@ -363,7 +372,7 @@ static ssize_t mdpy_write(struct mdev_device *mdev, const char __user *buf,
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
@@ -375,7 +384,7 @@ static ssize_t mdpy_write(struct mdev_device *mdev, const char __user *buf,
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;

- ret = mdev_access(mdev, (char *)&val, sizeof(val),
+ ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
@@ -393,9 +402,10 @@ static ssize_t mdpy_write(struct mdev_device *mdev, const char __user *buf,
return -EFAULT;
}

-static int mdpy_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
+static int mdpy_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
{
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);

if (vma->vm_pgoff != MDPY_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
return -EINVAL;
@@ -409,16 +419,10 @@ static int mdpy_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
return remap_vmalloc_range(vma, mdev_state->memblk, 0);
}

-static int mdpy_get_region_info(struct mdev_device *mdev,
+static int mdpy_get_region_info(struct mdev_state *mdev_state,
struct vfio_region_info *region_info,
u16 *cap_type_id, void **cap_type)
{
- struct mdev_state *mdev_state;
-
- mdev_state = mdev_get_drvdata(mdev);
- if (!mdev_state)
- return -EINVAL;
-
if (region_info->index >= VFIO_PCI_NUM_REGIONS &&
region_info->index != MDPY_DISPLAY_REGION)
return -EINVAL;
@@ -447,15 +451,13 @@ static int mdpy_get_region_info(struct mdev_device *mdev,
return 0;
}

-static int mdpy_get_irq_info(struct mdev_device *mdev,
- struct vfio_irq_info *irq_info)
+static int mdpy_get_irq_info(struct vfio_irq_info *irq_info)
{
irq_info->count = 0;
return 0;
}

-static int mdpy_get_device_info(struct mdev_device *mdev,
- struct vfio_device_info *dev_info)
+static int mdpy_get_device_info(struct vfio_device_info *dev_info)
{
dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
@@ -463,11 +465,9 @@ static int mdpy_get_device_info(struct mdev_device *mdev,
return 0;
}

-static int mdpy_query_gfx_plane(struct mdev_device *mdev,
+static int mdpy_query_gfx_plane(struct mdev_state *mdev_state,
struct vfio_device_gfx_plane_info *plane)
{
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
-
if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
VFIO_GFX_PLANE_TYPE_REGION))
@@ -496,14 +496,13 @@ static int mdpy_query_gfx_plane(struct mdev_device *mdev,
return 0;
}

-static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
+static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd,
unsigned long arg)
{
int ret = 0;
unsigned long minsz;
- struct mdev_state *mdev_state;
-
- mdev_state = mdev_get_drvdata(mdev);
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);

switch (cmd) {
case VFIO_DEVICE_GET_INFO:
@@ -518,7 +517,7 @@ static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
if (info.argsz < minsz)
return -EINVAL;

- ret = mdpy_get_device_info(mdev, &info);
+ ret = mdpy_get_device_info(&info);
if (ret)
return ret;

@@ -543,7 +542,7 @@ static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
if (info.argsz < minsz)
return -EINVAL;

- ret = mdpy_get_region_info(mdev, &info, &cap_type_id,
+ ret = mdpy_get_region_info(mdev_state, &info, &cap_type_id,
&cap_type);
if (ret)
return ret;
@@ -567,7 +566,7 @@ static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
(info.index >= mdev_state->dev_info.num_irqs))
return -EINVAL;

- ret = mdpy_get_irq_info(mdev, &info);
+ ret = mdpy_get_irq_info(&info);
if (ret)
return ret;

@@ -590,7 +589,7 @@ static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
if (plane.argsz < minsz)
return -EINVAL;

- ret = mdpy_query_gfx_plane(mdev, &plane);
+ ret = mdpy_query_gfx_plane(mdev_state, &plane);
if (ret)
return ret;

@@ -604,12 +603,12 @@ static long mdpy_ioctl(struct mdev_device *mdev, unsigned int cmd,
return -EINVAL;

case VFIO_DEVICE_RESET:
- return mdpy_reset(mdev);
+ return mdpy_reset(mdev_state);
}
return -ENOTTY;
}

-static int mdpy_open(struct mdev_device *mdev)
+static int mdpy_open(struct vfio_device *vdev)
{
if (!try_module_get(THIS_MODULE))
return -ENODEV;
@@ -617,7 +616,7 @@ static int mdpy_open(struct mdev_device *mdev)
return 0;
}

-static void mdpy_close(struct mdev_device *mdev)
+static void mdpy_close(struct vfio_device *vdev)
{
module_put(THIS_MODULE);
}
@@ -626,8 +625,7 @@ static ssize_t
resolution_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- struct mdev_device *mdev = mdev_from_dev(dev);
- struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+ struct mdev_state *mdev_state = dev_get_drvdata(dev);

return sprintf(buf, "%dx%d\n",
mdev_state->type->width,
@@ -716,18 +714,30 @@ static struct attribute_group *mdev_type_groups[] = {
NULL,
};

+static const struct vfio_device_ops mdpy_dev_ops = {
+ .open = mdpy_open,
+ .release = mdpy_close,
+ .read = mdpy_read,
+ .write = mdpy_write,
+ .ioctl = mdpy_ioctl,
+ .mmap = mdpy_mmap,
+};
+
+static struct mdev_driver mdpy_driver = {
+ .driver = {
+ .name = "mdpy",
+ .owner = THIS_MODULE,
+ .mod_name = KBUILD_MODNAME,
+ .dev_groups = mdev_dev_groups,
+ },
+ .probe = mdpy_probe,
+ .remove = mdpy_remove,
+};
+
static const struct mdev_parent_ops mdev_fops = {
.owner = THIS_MODULE,
- .mdev_attr_groups = mdev_dev_groups,
+ .device_driver = &mdpy_driver,
.supported_type_groups = mdev_type_groups,
- .create = mdpy_create,
- .remove = mdpy_remove,
- .open = mdpy_open,
- .release = mdpy_close,
- .read = mdpy_read,
- .write = mdpy_write,
- .ioctl = mdpy_ioctl,
- .mmap = mdpy_mmap,
};

static const struct file_operations vd_fops = {
@@ -752,11 +762,15 @@ static int __init mdpy_dev_init(void)
cdev_add(&mdpy_cdev, mdpy_devt, MINORMASK + 1);
pr_info("%s: major %d\n", __func__, MAJOR(mdpy_devt));

+ ret = mdev_register_driver(&mdpy_driver);
+ if (ret)
+ goto err_cdev;
+
mdpy_class = class_create(THIS_MODULE, MDPY_CLASS_NAME);
if (IS_ERR(mdpy_class)) {
pr_err("Error: failed to register mdpy_dev class\n");
ret = PTR_ERR(mdpy_class);
- goto failed1;
+ goto err_driver;
}
mdpy_dev.class = mdpy_class;
mdpy_dev.release = mdpy_device_release;
@@ -764,19 +778,21 @@ static int __init mdpy_dev_init(void)

ret = device_register(&mdpy_dev);
if (ret)
- goto failed2;
+ goto err_class;

ret = mdev_register_device(&mdpy_dev, &mdev_fops);
if (ret)
- goto failed3;
+ goto err_device;

return 0;

-failed3:
+err_device:
device_unregister(&mdpy_dev);
-failed2:
+err_class:
class_destroy(mdpy_class);
-failed1:
+err_driver:
+ mdev_unregister_driver(&mdpy_driver);
+err_cdev:
cdev_del(&mdpy_cdev);
unregister_chrdev_region(mdpy_devt, MINORMASK + 1);
return ret;
@@ -788,6 +804,7 @@ static void __exit mdpy_dev_exit(void)
mdev_unregister_device(&mdpy_dev);

device_unregister(&mdpy_dev);
+ mdev_unregister_driver(&mdpy_driver);
cdev_del(&mdpy_cdev);
unregister_chrdev_region(mdpy_devt, MINORMASK + 1);
class_destroy(mdpy_class);
--
2.30.2