vfio/mbochs: Convert to use vfio_register_group_dev()

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>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210617142218.1877096-11-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/samples/vfio-mdev/mbochs.c b/samples/vfio-mdev/mbochs.c
index 881ef9a7296f23ee6a26bc2bbd0f6f207c101b5a..6c0f229db36a1a2a5d30cccfb0a73c97ca6afe36 100644 (file)
--- a/samples/vfio-mdev/mbochs.c
+++ b/samples/vfio-mdev/mbochs.c
@@ -130,6 +130,7 @@ static struct class *mbochs_class;
 static struct cdev     mbochs_cdev;
 static struct device   mbochs_dev;
 static int             mbochs_used_mbytes;
+static const struct vfio_device_ops mbochs_dev_ops;
 
 struct vfio_region_info_ext {
        struct vfio_region_info          base;
@@ -160,6 +161,7 @@ struct mbochs_dmabuf {
 
 /* State of each mdev device */
 struct mdev_state {
+       struct vfio_device vdev;
        u8 *vconfig;
        u64 bar_mask[3];
        u32 memory_bar_mask;
@@ -425,11 +427,9 @@ static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
                memcpy(buf, mdev_state->edid_blob + offset, count);
 }
 
-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);
        struct page *pg;
        loff_t poff;
        char *map;
@@ -478,7 +478,7 @@ static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
                put_page(pg);
 
        } else {
-               dev_dbg(dev, "%s: %s @0x%llx (unhandled)\n",
+               dev_dbg(mdev_state->vdev.dev, "%s: %s @0x%llx (unhandled)\n",
                        __func__, is_write ? "WR" : "RD", pos);
                ret = -1;
                goto accessfailed;
@@ -493,9 +493,8 @@ accessfailed:
        return ret;
 }
 
-static int mbochs_reset(struct mdev_device *mdev)
+static int mbochs_reset(struct mdev_state *mdev_state)
 {
-       struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
        u32 size64k = mdev_state->memsize / (64 * 1024);
        int i;
 
@@ -506,12 +505,13 @@ static int mbochs_reset(struct mdev_device *mdev)
        return 0;
 }
 
-static int mbochs_create(struct mdev_device *mdev)
+static int mbochs_probe(struct mdev_device *mdev)
 {
        const struct mbochs_type *type =
                &mbochs_types[mdev_get_type_group_id(mdev)];
        struct device *dev = mdev_dev(mdev);
        struct mdev_state *mdev_state;
+       int ret = -ENOMEM;
 
        if (type->mbytes + mbochs_used_mbytes > max_mbytes)
                return -ENOMEM;
@@ -519,6 +519,7 @@ static int mbochs_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, &mbochs_dev_ops);
 
        mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
        if (mdev_state->vconfig == NULL)
@@ -537,7 +538,6 @@ static int mbochs_create(struct mdev_device *mdev)
 
        mutex_init(&mdev_state->ops_lock);
        mdev_state->mdev = mdev;
-       mdev_set_drvdata(mdev, mdev_state);
        INIT_LIST_HEAD(&mdev_state->dmabufs);
        mdev_state->next_id = 1;
 
@@ -547,32 +547,38 @@ static int mbochs_create(struct mdev_device *mdev)
        mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
        mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
        mbochs_create_config_space(mdev_state);
-       mbochs_reset(mdev);
+       mbochs_reset(mdev_state);
 
        mbochs_used_mbytes += type->mbytes;
+
+       ret = vfio_register_group_dev(&mdev_state->vdev);
+       if (ret)
+               goto err_mem;
+       dev_set_drvdata(&mdev->dev, mdev_state);
        return 0;
 
 err_mem:
        kfree(mdev_state->vconfig);
        kfree(mdev_state);
-       return -ENOMEM;
+       return ret;
 }
 
-static int mbochs_remove(struct mdev_device *mdev)
+static void mbochs_remove(struct mdev_device *mdev)
 {
-       struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+       struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 
        mbochs_used_mbytes -= mdev_state->type->mbytes;
-       mdev_set_drvdata(mdev, NULL);
+       vfio_unregister_group_dev(&mdev_state->vdev);
        kfree(mdev_state->pages);
        kfree(mdev_state->vconfig);
        kfree(mdev_state);
-       return 0;
 }
 
-static ssize_t mbochs_read(struct mdev_device *mdev, char __user *buf,
+static ssize_t mbochs_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;
 
@@ -582,7 +588,7 @@ static ssize_t mbochs_read(struct mdev_device *mdev, char __user *buf,
                if (count >= 4 && !(*ppos % 4)) {
                        u32 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;
@@ -594,7 +600,7 @@ static ssize_t mbochs_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;
@@ -606,7 +612,7 @@ static ssize_t mbochs_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;
@@ -629,9 +635,11 @@ read_err:
        return -EFAULT;
 }
 
-static ssize_t mbochs_write(struct mdev_device *mdev, const char __user *buf,
+static ssize_t mbochs_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;
 
@@ -644,7 +652,7 @@ static ssize_t mbochs_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;
@@ -656,7 +664,7 @@ static ssize_t mbochs_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;
@@ -668,7 +676,7 @@ static ssize_t mbochs_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;
@@ -754,9 +762,10 @@ static const struct vm_operations_struct mbochs_region_vm_ops = {
        .fault = mbochs_region_vm_fault,
 };
 
-static int mbochs_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
+static int mbochs_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 != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
                return -EINVAL;
@@ -963,7 +972,7 @@ mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
 static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
 {
        struct mdev_state *mdev_state = dmabuf->mdev_state;
-       struct device *dev = mdev_dev(mdev_state->mdev);
+       struct device *dev = mdev_state->vdev.dev;
        DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
        struct dma_buf *buf;
 
@@ -991,15 +1000,10 @@ static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
        return 0;
 }
 
-static int mbochs_get_region_info(struct mdev_device *mdev,
+static int mbochs_get_region_info(struct mdev_state *mdev_state,
                                  struct vfio_region_info_ext *ext)
 {
        struct vfio_region_info *region_info = &ext->base;
-       struct mdev_state *mdev_state;
-
-       mdev_state = mdev_get_drvdata(mdev);
-       if (!mdev_state)
-               return -EINVAL;
 
        if (region_info->index >= MBOCHS_NUM_REGIONS)
                return -EINVAL;
@@ -1047,15 +1051,13 @@ static int mbochs_get_region_info(struct mdev_device *mdev,
        return 0;
 }
 
-static int mbochs_get_irq_info(struct mdev_device *mdev,
-                              struct vfio_irq_info *irq_info)
+static int mbochs_get_irq_info(struct vfio_irq_info *irq_info)
 {
        irq_info->count = 0;
        return 0;
 }
 
-static int mbochs_get_device_info(struct mdev_device *mdev,
-                                 struct vfio_device_info *dev_info)
+static int mbochs_get_device_info(struct vfio_device_info *dev_info)
 {
        dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
        dev_info->num_regions = MBOCHS_NUM_REGIONS;
@@ -1063,11 +1065,9 @@ static int mbochs_get_device_info(struct mdev_device *mdev,
        return 0;
 }
 
-static int mbochs_query_gfx_plane(struct mdev_device *mdev,
+static int mbochs_query_gfx_plane(struct mdev_state *mdev_state,
                                  struct vfio_device_gfx_plane_info *plane)
 {
-       struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
-       struct device *dev = mdev_dev(mdev);
        struct mbochs_dmabuf *dmabuf;
        struct mbochs_mode mode;
        int ret;
@@ -1121,18 +1121,16 @@ static int mbochs_query_gfx_plane(struct mdev_device *mdev,
 done:
        if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
            mdev_state->active_id != plane->dmabuf_id) {
-               dev_dbg(dev, "%s: primary: %d => %d\n", __func__,
-                       mdev_state->active_id, plane->dmabuf_id);
+               dev_dbg(mdev_state->vdev.dev, "%s: primary: %d => %d\n",
+                       __func__, mdev_state->active_id, plane->dmabuf_id);
                mdev_state->active_id = plane->dmabuf_id;
        }
        mutex_unlock(&mdev_state->ops_lock);
        return 0;
 }
 
-static int mbochs_get_gfx_dmabuf(struct mdev_device *mdev,
-                                u32 id)
+static int mbochs_get_gfx_dmabuf(struct mdev_state *mdev_state, u32 id)
 {
-       struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
        struct mbochs_dmabuf *dmabuf;
 
        mutex_lock(&mdev_state->ops_lock);
@@ -1154,9 +1152,11 @@ static int mbochs_get_gfx_dmabuf(struct mdev_device *mdev,
        return dma_buf_fd(dmabuf->buf, 0);
 }
 
-static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
-                       unsigned long arg)
+static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd,
+                        unsigned long arg)
 {
+       struct mdev_state *mdev_state =
+               container_of(vdev, struct mdev_state, vdev);
        int ret = 0;
        unsigned long minsz, outsz;
 
@@ -1173,7 +1173,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                if (info.argsz < minsz)
                        return -EINVAL;
 
-               ret = mbochs_get_device_info(mdev, &info);
+               ret = mbochs_get_device_info(&info);
                if (ret)
                        return ret;
 
@@ -1197,7 +1197,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                if (outsz > sizeof(info))
                        return -EINVAL;
 
-               ret = mbochs_get_region_info(mdev, &info);
+               ret = mbochs_get_region_info(mdev_state, &info);
                if (ret)
                        return ret;
 
@@ -1220,7 +1220,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                    (info.index >= VFIO_PCI_NUM_IRQS))
                        return -EINVAL;
 
-               ret = mbochs_get_irq_info(mdev, &info);
+               ret = mbochs_get_irq_info(&info);
                if (ret)
                        return ret;
 
@@ -1243,7 +1243,7 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                if (plane.argsz < minsz)
                        return -EINVAL;
 
-               ret = mbochs_query_gfx_plane(mdev, &plane);
+               ret = mbochs_query_gfx_plane(mdev_state, &plane);
                if (ret)
                        return ret;
 
@@ -1260,19 +1260,19 @@ static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
                if (get_user(dmabuf_id, (__u32 __user *)arg))
                        return -EFAULT;
 
-               return mbochs_get_gfx_dmabuf(mdev, dmabuf_id);
+               return mbochs_get_gfx_dmabuf(mdev_state, dmabuf_id);
        }
 
        case VFIO_DEVICE_SET_IRQS:
                return -EINVAL;
 
        case VFIO_DEVICE_RESET:
-               return mbochs_reset(mdev);
+               return mbochs_reset(mdev_state);
        }
        return -ENOTTY;
 }
 
-static int mbochs_open(struct mdev_device *mdev)
+static int mbochs_open(struct vfio_device *vdev)
 {
        if (!try_module_get(THIS_MODULE))
                return -ENODEV;
@@ -1280,9 +1280,10 @@ static int mbochs_open(struct mdev_device *mdev)
        return 0;
 }
 
-static void mbochs_close(struct mdev_device *mdev)
+static void mbochs_close(struct vfio_device *vdev)
 {
-       struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
+       struct mdev_state *mdev_state =
+               container_of(vdev, struct mdev_state, vdev);
        struct mbochs_dmabuf *dmabuf, *tmp;
 
        mutex_lock(&mdev_state->ops_lock);
@@ -1306,8 +1307,7 @@ static ssize_t
 memory_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, "%d MB\n", mdev_state->type->mbytes);
 }
@@ -1398,18 +1398,30 @@ static struct attribute_group *mdev_type_groups[] = {
        NULL,
 };
 
+static const struct vfio_device_ops mbochs_dev_ops = {
+       .open = mbochs_open,
+       .release = mbochs_close,
+       .read = mbochs_read,
+       .write = mbochs_write,
+       .ioctl = mbochs_ioctl,
+       .mmap = mbochs_mmap,
+};
+
+static struct mdev_driver mbochs_driver = {
+       .driver = {
+               .name = "mbochs",
+               .owner = THIS_MODULE,
+               .mod_name = KBUILD_MODNAME,
+               .dev_groups = mdev_dev_groups,
+       },
+       .probe = mbochs_probe,
+       .remove = mbochs_remove,
+};
+
 static const struct mdev_parent_ops mdev_fops = {
        .owner                  = THIS_MODULE,
-       .mdev_attr_groups       = mdev_dev_groups,
+       .device_driver          = &mbochs_driver,
        .supported_type_groups  = mdev_type_groups,
-       .create                 = mbochs_create,
-       .remove                 = mbochs_remove,
-       .open                   = mbochs_open,
-       .release                = mbochs_close,
-       .read                   = mbochs_read,
-       .write                  = mbochs_write,
-       .ioctl                  = mbochs_ioctl,
-       .mmap                   = mbochs_mmap,
 };
 
 static const struct file_operations vd_fops = {
@@ -1434,11 +1446,15 @@ static int __init mbochs_dev_init(void)
        cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK + 1);
        pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
 
+       ret = mdev_register_driver(&mbochs_driver);
+       if (ret)
+               goto err_cdev;
+
        mbochs_class = class_create(THIS_MODULE, MBOCHS_CLASS_NAME);
        if (IS_ERR(mbochs_class)) {
                pr_err("Error: failed to register mbochs_dev class\n");
                ret = PTR_ERR(mbochs_class);
-               goto failed1;
+               goto err_driver;
        }
        mbochs_dev.class = mbochs_class;
        mbochs_dev.release = mbochs_device_release;
@@ -1446,19 +1462,21 @@ static int __init mbochs_dev_init(void)
 
        ret = device_register(&mbochs_dev);
        if (ret)
-               goto failed2;
+               goto err_class;
 
        ret = mdev_register_device(&mbochs_dev, &mdev_fops);
        if (ret)
-               goto failed3;
+               goto err_device;
 
        return 0;
 
-failed3:
+err_device:
        device_unregister(&mbochs_dev);
-failed2:
+err_class:
        class_destroy(mbochs_class);
-failed1:
+err_driver:
+       mdev_unregister_driver(&mbochs_driver);
+err_cdev:
        cdev_del(&mbochs_cdev);
        unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
        return ret;
@@ -1470,6 +1488,7 @@ static void __exit mbochs_dev_exit(void)
        mdev_unregister_device(&mbochs_dev);
 
        device_unregister(&mbochs_dev);
+       mdev_unregister_driver(&mbochs_driver);
        cdev_del(&mbochs_cdev);
        unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
        class_destroy(mbochs_class);