Re: [RFC 02/18] remoteproc: Introduce virtio device add/remove functions in core.

From: Mathieu Poirier
Date: Wed Apr 22 2020 - 12:57:28 EST


This morning I'm attempting to take a fresh look at this set...

On Thu, Apr 16, 2020 at 06:13:15PM +0200, Arnaud Pouliquen wrote:
> In preparation of the migration of the management of rvdev in
> rproc_virtio, this patch spins off new functions to manage the
> virtio device.
>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
> ---
> drivers/remoteproc/remoteproc_core.c | 149 +++++++++++++++------------
> 1 file changed, 83 insertions(+), 66 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 2a0425ab82a7..5c90d569c0f7 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -441,6 +441,86 @@ static void rproc_rvdev_release(struct device *dev)
> kfree(rvdev);
> }
>
> +static int rproc_rvdev_add_device(struct rproc_vdev *rvdev)
> +{
> + struct rproc *rproc = rvdev->rproc;
> + struct fw_rsc_vdev *rsc = rvdev->rsc;
> + char name[16];
> + int ret, i;
> +
> + /* Initialise vdev subdevice */
> + snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
> + rvdev->dev.parent = &rproc->dev;
> + rvdev->dev.dma_pfn_offset = rproc->dev.parent->dma_pfn_offset;
> + 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;
> + }
> + /* Make device dma capable by inheriting from parent's capabilities */
> + set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
> +
> + ret = dma_coerce_mask_and_coherent(&rvdev->dev,
> + dma_get_mask(rproc->dev.parent));
> + if (ret) {
> + dev_warn(&rvdev->dev,
> + "Failed to set DMA mask %llx. Trying to continue... %x\n",
> + dma_get_mask(rproc->dev.parent), ret);
> + }
> +
> + /* parse the vrings */
> + for (i = 0; i < rsc->num_of_vrings; i++) {
> + ret = rproc_parse_vring(rvdev, rsc, i);
> + if (ret)
> + goto free_rvdev;
> + }
> +
> + /* allocate the vring resources */
> + for (i = 0; i < rsc->num_of_vrings; i++) {
> + ret = rproc_alloc_vring(rvdev, i);
> + if (ret)
> + goto free_vg;
> + }
> +
> + rvdev->subdev.start = rproc_vdev_do_start;
> + rvdev->subdev.stop = rproc_vdev_do_stop;
> +
> + rproc_add_subdev(rproc, &rvdev->subdev);
> +
> + return 0;
> +
> +free_vg:
> + for (i--; i >= 0; i--) {
> + struct rproc_vring *rvring = &rvdev->vring[i];
> +
> + rproc_free_vring(rvring);
> + }
> +
> +free_rvdev:
> + device_unregister(&rvdev->dev);
> +
> + return ret;
> +}
> +
> +static void rproc_rvdev_remove_device(struct rproc_vdev *rvdev)
> +{
> + struct rproc *rproc = rvdev->rproc;
> + struct rproc_vring *rvring;
> + int id;
> +
> + for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
> + rvring = &rvdev->vring[id];
> + rproc_free_vring(rvring);
> + }
> +
> + rproc_remove_subdev(rproc, &rvdev->subdev);
> + device_unregister(&rvdev->dev);
> +}
> +
> /**
> * rproc_handle_vdev() - handle a vdev fw resource
> * @rproc: the remote processor
> @@ -473,8 +553,6 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
> {
> struct device *dev = &rproc->dev;
> struct rproc_vdev *rvdev;
> - int i, ret;
> - char name[16];
>
> /* make sure resource isn't truncated */
> if (struct_size(rsc, vring, rsc->num_of_vrings) + rsc->config_len >
> @@ -505,83 +583,22 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
> kref_init(&rvdev->refcount);
>
> rvdev->rsc = rsc;
> + rvdev->rsc_offset = offset;
> rvdev->id = rsc->id;
> rvdev->rproc = rproc;
> rvdev->index = rproc->nb_vdev++;
>
> - /* Initialise vdev subdevice */
> - snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
> - rvdev->dev.parent = rproc->dev.parent;
> - rvdev->dev.dma_pfn_offset = rproc->dev.parent->dma_pfn_offset;
> - 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;
> - }
> - /* Make device dma capable by inheriting from parent's capabilities */
> - set_dma_ops(&rvdev->dev, get_dma_ops(rproc->dev.parent));
> -
> - ret = dma_coerce_mask_and_coherent(&rvdev->dev,
> - dma_get_mask(rproc->dev.parent));
> - if (ret) {
> - dev_warn(dev,
> - "Failed to set DMA mask %llx. Trying to continue... %x\n",
> - dma_get_mask(rproc->dev.parent), ret);
> - }
> -
> - /* parse the vrings */
> - for (i = 0; i < rsc->num_of_vrings; i++) {
> - ret = rproc_parse_vring(rvdev, rsc, i);
> - if (ret)
> - 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);
> - if (ret)
> - goto unwind_vring_allocations;
> - }
> -
> list_add_tail(&rvdev->node, &rproc->rvdevs);

This should go in rproc_rvdev_add_device()

>
> - rvdev->subdev.start = rproc_vdev_do_start;
> - rvdev->subdev.stop = rproc_vdev_do_stop;
> -
> - rproc_add_subdev(rproc, &rvdev->subdev);
> -
> - return 0;
> -
> -unwind_vring_allocations:
> - for (i--; i >= 0; i--)
> - rproc_free_vring(&rvdev->vring[i]);
> -free_rvdev:
> - device_unregister(&rvdev->dev);
> - return ret;
> + return rproc_rvdev_add_device(rvdev);
> }
>
> void rproc_vdev_release(struct kref *ref)
> {
> struct rproc_vdev *rvdev = container_of(ref, struct rproc_vdev, refcount);
> - struct rproc_vring *rvring;
> - struct rproc *rproc = rvdev->rproc;
> - int id;
> -
> - for (id = 0; id < ARRAY_SIZE(rvdev->vring); id++) {
> - rvring = &rvdev->vring[id];
> - rproc_free_vring(rvring);
> - }
>
> - rproc_remove_subdev(rproc, &rvdev->subdev);
> + rproc_rvdev_remove_device(rvdev);
> list_del(&rvdev->node);
> - device_unregister(&rvdev->dev);

Keep this function intact, rename it rproc_rvdev_remove_device() to balance out
rproc_rvdev_add_device() and modify rproc_resource_cleanup() to reflect the
change. I suppose we have nothing to loose since rproc_handle_vdev() and
rproc_vdev_release(), from a syntactic point of view, didn't balance each other
out.

> }
>
> /**
> --
> 2.17.1
>