On Wed, Dec 22, 2021 at 09:23:49AM +0100, Arnaud Pouliquen wrote:
> Migrate from the rvdev device to the rvdev platform device.
> From this patch, when a vdev resource is found in the resource table
> the remoteproc core register a platform device.
>
> All reference to the rvdev->dev has been updated to rvdev-pdev->dev
>
> The use of kref counter is replaced by get/put_device on the remoteproc
> virtio device.
>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>
> ---
> Update vs previous revision:
> - rework comments around virtio platform device creation
> ---
> drivers/remoteproc/remoteproc_core.c | 48 +++++++-----
> drivers/remoteproc/remoteproc_internal.h | 2 -
> drivers/remoteproc/remoteproc_virtio.c | 99 ++++++------------------
> include/linux/remoteproc.h | 4 -
> 4 files changed, 52 insertions(+), 101 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index ca2fe8d9cac8..4f332ec0fdd0 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -465,6 +465,8 @@ static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
> {
> struct fw_rsc_vdev *rsc = ptr;
> struct device *dev = &rproc->dev;
> + struct rproc_vdev_pdata vdev_data;
> + struct platform_device *pdev;
> struct rproc_vdev *rvdev;
> int i, ret;
>
> @@ -484,25 +486,36 @@ static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
> dev_dbg(dev, "vdev rsc: id %d, dfeatures 0x%x, cfg len %d, %d vrings\n",
> rsc->id, rsc->dfeatures, rsc->config_len, rsc->num_of_vrings);
>
> - /* we currently support only two vrings per rvdev */
> - if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) {
> - dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings);
> - return -EINVAL;
> - }
> + /* Register a remoteproc virtio platform device in charge of the virtio device */
> + vdev_data.rsc_offset = offset;
> + vdev_data.id = rsc->id;
> + vdev_data.index = rproc->nb_vdev;
>
> - rvdev = kzalloc(sizeof(*rvdev), GFP_KERNEL);
> - if (!rvdev)
> - return -ENOMEM;
> + pdev = rproc_virtio_register_device(rproc, &vdev_data);
> + if (PTR_ERR_OR_ZERO(pdev)) {
> + dev_err(rproc->dev.parent,
> + "failed to create rproc-virtio device\n");
> + return PTR_ERR_OR_ZERO(pdev);
The error check and dev_err() message is exactly the same as what is found in
rproc_virtio_register_device(). As such two error messages will be printed out
for every single failure. I would call platform_device_register_data() directly
rather than keeping rproc_virtio_register_device() around.
> + }
>
> - kref_init(&rvdev->refcount);
> + /*
> + * At this point the registered remoteproc virtio platform device should has been probed.
s/has been/have been
> + * Get the associated rproc_vdev struct to assign the vrings
> + */
> + rvdev = platform_get_drvdata(pdev);
> + if (WARN_ON(!rvdev)) {
> + ret = -EINVAL;
> + goto free_rvdev;
> + }
>
> - rvdev->id = rsc->id;
> - rvdev->rproc = rproc;
> - rvdev->index = rproc->nb_vdev++;
> + rproc->nb_vdev++;
>
> - ret = rproc_rvdev_add_device(rvdev);
> - if (ret)
> + /* we currently support only two vrings per rvdev */
> + if (rsc->num_of_vrings > ARRAY_SIZE(rvdev->vring)) {
> + dev_err(dev, "too many vrings: %d\n", rsc->num_of_vrings);
> + ret = -EINVAL;
> goto free_rvdev;
> + }
>
> /* parse the vrings */
> for (i = 0; i < rsc->num_of_vrings; i++) {
> @@ -511,9 +524,6 @@ static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
> goto free_rvdev;
> }
>
> - /* remember the resource offset*/
> - rvdev->rsc_offset = offset;
> -
> /* allocate the vring resources */
> for (i = 0; i < rsc->num_of_vrings; i++) {
> ret = rproc_alloc_vring(rvdev, i);
> @@ -527,7 +537,7 @@ static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
> for (i--; i >= 0; i--)
> rproc_free_vring(&rvdev->vring[i]);
> free_rvdev:
> - device_unregister(&rvdev->dev);
> + rproc_virtio_unregister_device(rvdev);
Here too I wouldn't bother with a new function - I would simply call
platform_device_unregister().
> return ret;
> }
>
> @@ -1266,7 +1276,7 @@ void rproc_resource_cleanup(struct rproc *rproc)
>
> /* clean up remote vdev entries */
> list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
> - kref_put(&rvdev->refcount, rproc_vdev_release);
> + rproc_virtio_unregister_device(rvdev);
Same as above.
>
> rproc_coredump_cleanup(rproc);
> }
> diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h
> index 3007d29a26e1..1479c5e33e2e 100644
> --- a/drivers/remoteproc/remoteproc_internal.h
> +++ b/drivers/remoteproc/remoteproc_internal.h
> @@ -36,12 +36,10 @@ int rproc_of_parse_firmware(struct device *dev, int index,
> const char **fw_name);
>
> /* from remoteproc_virtio.c */
> -int rproc_rvdev_add_device(struct rproc_vdev *rvdev);
> struct platform_device *
> rproc_virtio_register_device(struct rproc *rproc, struct rproc_vdev_pdata *vdev_data);
> void rproc_virtio_unregister_device(struct rproc_vdev *rvdev);
> irqreturn_t rproc_vq_interrupt(struct rproc *rproc, int vq_id);
> -void rproc_vdev_release(struct kref *ref);
>
> /* from remoteproc_debugfs.c */
> void rproc_remove_trace_file(struct dentry *tfile);
> diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
> index 5eef679cc520..55e797095bfe 100644
> --- a/drivers/remoteproc/remoteproc_virtio.c
> +++ b/drivers/remoteproc/remoteproc_virtio.c
> @@ -48,7 +48,11 @@ static int copy_dma_range_map(struct device *to, struct device *from)
>
> static struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
> {
> - return container_of(vdev->dev.parent, struct rproc_vdev, dev);
> + struct platform_device *pdev;
> +
> + pdev = container_of(vdev->dev.parent, struct platform_device, dev);
> +
> + return platform_get_drvdata(pdev);
> }
>
> static struct rproc *vdev_to_rproc(struct virtio_device *vdev)
> @@ -343,13 +347,10 @@ static void rproc_virtio_dev_release(struct device *dev)
> {
> struct virtio_device *vdev = dev_to_virtio(dev);
> struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
> - struct rproc *rproc = vdev_to_rproc(vdev);
>
> kfree(vdev);
>
> - kref_put(&rvdev->refcount, rproc_vdev_release);
> -
> - put_device(&rproc->dev);
> + put_device(&rvdev->pdev->dev);
> }
>
> /**
> @@ -365,7 +366,7 @@ static void rproc_virtio_dev_release(struct device *dev)
> static int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
> {
> struct rproc *rproc = rvdev->rproc;
> - struct device *dev = &rvdev->dev;
> + struct device *dev = &rvdev->pdev->dev;
> struct virtio_device *vdev;
> struct rproc_mem_entry *mem;
> int ret;
> @@ -436,17 +437,15 @@ static int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
> vdev->dev.release = rproc_virtio_dev_release;
>
> /*
> - * We're indirectly making a non-temporary copy of the rproc pointer
> + * We're indirectly making a non-temporary copy of the rvdev pointer
> * here, because drivers probed with this vdev will indirectly
> * access the wrapping rproc.
> *
> - * Therefore we must increment the rproc refcount here, and decrement
> + * Therefore we must increment the rvdev refcount here, and decrement
> * it _only_ when the vdev is released.
> */
> - get_device(&rproc->dev);
> + get_device(dev);
>
> - /* Reference the vdev and vring allocations */
> - kref_get(&rvdev->refcount);
>
> ret = register_virtio_device(vdev);
> if (ret) {
> @@ -488,56 +487,30 @@ static int rproc_vdev_do_start(struct rproc_subdev *subdev)
> static void rproc_vdev_do_stop(struct rproc_subdev *subdev, bool crashed)
> {
> struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
> + struct device *dev = &rvdev->pdev->dev;
> int ret;
>
> - ret = device_for_each_child(&rvdev->dev, NULL, rproc_remove_virtio_dev);
> + ret = device_for_each_child(dev, NULL, rproc_remove_virtio_dev);
> if (ret)
> - dev_warn(&rvdev->dev, "can't remove vdev child device: %d\n", ret);
> -}
> -
> -/**
> - * rproc_rvdev_release() - release the existence of a rvdev
> - *
> - * @dev: the subdevice's dev
> - */
> -static void rproc_rvdev_release(struct device *dev)
> -{
> - struct rproc_vdev *rvdev = container_of(dev, struct rproc_vdev, dev);
> -
> - of_reserved_mem_device_release(dev);
> -
> - kfree(rvdev);
> + dev_warn(dev, "can't remove vdev child device: %d\n", ret);
> }
>
> -int rproc_rvdev_add_device(struct rproc_vdev *rvdev)
> +static int rproc_rvdev_add_device(struct rproc_vdev *rvdev)
> {
> struct rproc *rproc = rvdev->rproc;
> - char name[16];
> + struct device *dev = &rvdev->pdev->dev;
> int ret;
>
> - snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
> - rvdev->dev.parent = &rproc->dev;
> - rvdev->dev.release = rproc_rvdev_release;
> - dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev->dev.parent), name);
> - dev_set_drvdata(&rvdev->dev, rvdev);
> -
> - ret = device_register(&rvdev->dev);
> - if (ret) {
> - put_device(&rvdev->dev);
> - return ret;
> - }
> - ret = copy_dma_range_map(&rvdev->dev, rproc->dev.parent);
> + ret = copy_dma_range_map(dev, rproc->dev.parent);
> if (ret)
> - goto free_rvdev;
> + return ret;
>
> /* Make device dma capable by inheriting from parent's capabilities */
> - set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
> + set_dma_ops(dev, get_dma_ops(rproc->dev.parent));
>
> - ret = dma_coerce_mask_and_coherent(&rvdev->dev,
> - dma_get_mask(rproc->dev.parent));
> + ret = dma_coerce_mask_and_coherent(dev, dma_get_mask(rproc->dev.parent));
> if (ret) {
> - dev_warn(&rvdev->dev,
> - "Failed to set DMA mask %llx. Trying to continue... (%pe)\n",
> + dev_warn(dev, "Failed to set DMA mask %llx. Trying to continue... (%pe)\n",
> dma_get_mask(rproc->dev.parent), ERR_PTR(ret));
> }
>
> @@ -548,34 +521,9 @@ int rproc_rvdev_add_device(struct rproc_vdev *rvdev)
>
> rproc_add_subdev(rproc, &rvdev->subdev);
>
> - return 0;
> + dev_dbg(dev, "virtio dev %d added\n", rvdev->index);
>
> -free_rvdev:
> - device_unregister(&rvdev->dev);
> - return ret;
> -}
> -
> -static void rproc_rvdev_remove_device(struct rproc_vdev *rvdev)
> -{
> - struct rproc *rproc = rvdev->rproc;
> -
> - rproc_remove_subdev(rproc, &rvdev->subdev);
> - rproc_unregister_rvdev(rvdev);
> - device_unregister(&rvdev->dev);
> -}
> -
> -void rproc_vdev_release(struct kref *ref)
> -{
> - struct rproc_vdev *rvdev = container_of(ref, struct rproc_vdev, refcount);
> - struct rproc_vring *rvring;
> - int id;
> -
> - for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
> - rvring = &rvdev->vring[id];
> - rproc_free_vring(rvring);
> - }
> -
> - rproc_rvdev_remove_device(rvdev);
> + return 0;
> }
>
> /**
> @@ -594,8 +542,7 @@ rproc_virtio_register_device(struct rproc *rproc, struct rproc_vdev_pdata *vdev_
> pdev = platform_device_register_data(dev, "rproc-virtio", vdev_data->index, vdev_data,
> sizeof(*vdev_data));
> if (PTR_ERR_OR_ZERO(pdev)) {
> - dev_err(rproc->dev.parent,
> - "failed to create rproc-virtio device\n");
> + dev_err(rproc->dev.parent, "failed to create rproc-virtio device\n");
> }
>
> return pdev;
> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> index 542a3d4664f2..7951a3e2b62a 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -614,10 +614,8 @@ struct rproc_vring {
>
> /**
> * struct rproc_vdev - remoteproc state for a supported virtio device
> - * @refcount: reference counter for the vdev and vring allocations
> * @subdev: handle for registering the vdev as a rproc subdevice
> * @pdev: remoteproc virtio platform device
> - * @dev: device struct used for reference count semantics
> * @id: virtio device id (as in virtio_ids.h)
> * @node: list node
> * @rproc: the rproc handle
> @@ -626,11 +624,9 @@ struct rproc_vring {
> * @index: vdev position versus other vdev declared in resource table
> */
> struct rproc_vdev {
> - struct kref refcount;
>
> struct rproc_subdev subdev;
> struct platform_device *pdev;
> - struct device dev;
>
> unsigned int id;
> struct list_head node;
> --
> 2.17.1
>
