[PATCH v3 06/15] vfio/mtty: Use the new device life cycle helpers

From: Kevin Tian
Date: Thu Sep 08 2022 - 23:05:01 EST


From: Yi Liu <yi.l.liu@xxxxxxxxx>

and manage available ports inside @init/@release.

Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
Signed-off-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
---
samples/vfio-mdev/mtty.c | 67 +++++++++++++++++++++++-----------------
1 file changed, 39 insertions(+), 28 deletions(-)

diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
index f42a59ed2e3f..41301d50b247 100644
--- a/samples/vfio-mdev/mtty.c
+++ b/samples/vfio-mdev/mtty.c
@@ -703,9 +703,11 @@ static ssize_t mdev_access(struct mdev_state *mdev_state, u8 *buf, size_t count,
return ret;
}

-static int mtty_probe(struct mdev_device *mdev)
+static int mtty_init_dev(struct vfio_device *vdev)
{
- struct mdev_state *mdev_state;
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);
+ struct mdev_device *mdev = to_mdev_device(vdev->dev);
int nr_ports = mdev_get_type_group_id(mdev) + 1;
int avail_ports = atomic_read(&mdev_avail_ports);
int ret;
@@ -716,58 +718,65 @@ static int mtty_probe(struct mdev_device *mdev)
} while (!atomic_try_cmpxchg(&mdev_avail_ports,
&avail_ports, avail_ports - nr_ports));

- mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
- if (mdev_state == NULL) {
- ret = -ENOMEM;
- goto err_nr_ports;
- }
-
- vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mtty_dev_ops);
-
mdev_state->nr_ports = nr_ports;
mdev_state->irq_index = -1;
mdev_state->s[0].max_fifo_size = MAX_FIFO_SIZE;
mdev_state->s[1].max_fifo_size = MAX_FIFO_SIZE;
mutex_init(&mdev_state->rxtx_lock);
- mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);

- if (mdev_state->vconfig == NULL) {
+ mdev_state->vconfig = kzalloc(MTTY_CONFIG_SPACE_SIZE, GFP_KERNEL);
+ if (!mdev_state->vconfig) {
ret = -ENOMEM;
- goto err_state;
+ goto err_nr_ports;
}

mutex_init(&mdev_state->ops_lock);
mdev_state->mdev = mdev;
-
mtty_create_config_space(mdev_state);
+ return 0;
+
+err_nr_ports:
+ atomic_add(nr_ports, &mdev_avail_ports);
+ return ret;
+}
+
+static int mtty_probe(struct mdev_device *mdev)
+{
+ struct mdev_state *mdev_state;
+ int ret;
+
+ mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev,
+ &mtty_dev_ops);
+ if (IS_ERR(mdev_state))
+ return PTR_ERR(mdev_state);

ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
if (ret)
- goto err_vconfig;
+ goto err_put_vdev;
dev_set_drvdata(&mdev->dev, mdev_state);
return 0;

-err_vconfig:
- kfree(mdev_state->vconfig);
-err_state:
- vfio_uninit_group_dev(&mdev_state->vdev);
- kfree(mdev_state);
-err_nr_ports:
- atomic_add(nr_ports, &mdev_avail_ports);
+err_put_vdev:
+ vfio_put_device(&mdev_state->vdev);
return ret;
}

+static void mtty_release_dev(struct vfio_device *vdev)
+{
+ struct mdev_state *mdev_state =
+ container_of(vdev, struct mdev_state, vdev);
+
+ kfree(mdev_state->vconfig);
+ vfio_free_device(vdev);
+ atomic_add(mdev_state->nr_ports, &mdev_avail_ports);
+}
+
static void mtty_remove(struct mdev_device *mdev)
{
struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
- int nr_ports = mdev_state->nr_ports;

vfio_unregister_group_dev(&mdev_state->vdev);
-
- kfree(mdev_state->vconfig);
- vfio_uninit_group_dev(&mdev_state->vdev);
- kfree(mdev_state);
- atomic_add(nr_ports, &mdev_avail_ports);
+ vfio_put_device(&mdev_state->vdev);
}

static int mtty_reset(struct mdev_state *mdev_state)
@@ -1287,6 +1296,8 @@ static struct attribute_group *mdev_type_groups[] = {

static const struct vfio_device_ops mtty_dev_ops = {
.name = "vfio-mtty",
+ .init = mtty_init_dev,
+ .release = mtty_release_dev,
.read = mtty_read,
.write = mtty_write,
.ioctl = mtty_ioctl,
--
2.21.3