Thu, Jul 04, 2024 at 09:47:09AM CEST, [email protected] wrote:
>On Thu, Jul 04, 2024 at 08:43:35AM +0200, Jiri Pirko wrote:
>> From: Jiri Pirko <[email protected]>
>>
>> Introduce a structure virtio_queue_info to carry name, callback and ctx
>> together. In order to allow config implementations to accept config op
>> with array of virtio_queue_info structures, introduce a new
>> find_vqs_info() op. Do the needed conversion in virtio_find_vqs_ctx().
>> Note that whole virtio_find_vqs_ctx() is going to be eventually removed
>> at the and of this patchset.
>>
>> Signed-off-by: Jiri Pirko <[email protected]>
>> ---
>> v1->v2:
>> - fixed comments for struct virtqueue_info
>> - s/virtio_queue_info/virtqueue_info/
>> ---
>> include/linux/virtio_config.h | 51 ++++++++++++++++++++++++++++++++---
>> 1 file changed, 48 insertions(+), 3 deletions(-)
>>
>> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
>> index 82a1d798b2f1..9b975c2830f6 100644
>> --- a/include/linux/virtio_config.h
>> +++ b/include/linux/virtio_config.h
>> @@ -18,6 +18,16 @@ struct virtio_shm_region {
>>
>> typedef void vq_callback_t(struct virtqueue *);
>>
>> +struct virtqueue_info {
>> + const char *name; /* Mainly for debugging, may be NULL for a virtqueue
>> + * unused by driver.
>> + */
>> + vq_callback_t *callback; /* May be NULL for vq that does
>> + * not need a callback.
>> + */
>> + bool ctx;
>
>
> /*
> * Always
> * like this
> * outside of netdev code
> * and it comes before the code being documented
> */
>
> /* Never
> * like this
> */
How about to properly document the struct instead like this:
/**
* struct virtqueue_info - info for a virtqueue passed to find_vqs()
* @name: mainly for debugging, NULL for a virtqueue
* unused by the driver
* @callback: NULL for a virtqueue that does not need a callback
* @ctx: true to allow to maintain extra context per virtqueue
*/
struct virtqueue_info {
const char *name;
vq_callback_t *callback;
bool ctx;
};
>
>
>Also "may be null" is a bit confusing - it has to be null
>for such a vq.
>
>Thus:
>
> /*
> * name: mainly for debugging, NULL for a virtqueue
> * unused by the driver.
> */
> const char *name;
>
>and similarly for the callback.
>
>
>
>> +};
>> +
>> /**
>> * struct virtio_config_ops - operations for configuring a virtio device
>> * Note: Do not assume that a transport implements all of the operations
>> @@ -58,6 +68,12 @@ typedef void vq_callback_t(struct virtqueue *);
>> * names: array of virtqueue names (mainly for debugging)
>> * include a NULL entry for vqs unused by driver
>> * Returns 0 on success or error status
>> + * @find_vqs_info: find virtqueues and instantiate them.
>> + * vdev: the virtio_device
>> + * nvqs: the number of virtqueues to find
>> + * vqs: on success, includes new virtqueues
>> + * vqs_info: array of virtqueue info structures
>> + * Returns 0 on success or error status
>> * @del_vqs: free virtqueues found by find_vqs().
>> * @synchronize_cbs: synchronize with the virtqueue callbacks (optional)
>> * The function guarantees that all memory operations on the
>> @@ -109,6 +125,10 @@ struct virtio_config_ops {
>> struct virtqueue *vqs[], vq_callback_t *callbacks[],
>> const char * const names[], const bool *ctx,
>> struct irq_affinity *desc);
>> + int (*find_vqs_info)(struct virtio_device *vdev, unsigned int nvqs,
>> + struct virtqueue *vqs[],
>> + struct virtqueue_info vqs_info[],
>> + struct irq_affinity *desc);
>> void (*del_vqs)(struct virtio_device *);
>> void (*synchronize_cbs)(struct virtio_device *);
>> u64 (*get_features)(struct virtio_device *vdev);
>> @@ -117,7 +137,7 @@ struct virtio_config_ops {
>> int (*set_vq_affinity)(struct virtqueue *vq,
>> const struct cpumask *cpu_mask);
>> const struct cpumask *(*get_vq_affinity)(struct virtio_device *vdev,
>> - int index);
>> + int index);
>> bool (*get_shm_region)(struct virtio_device *vdev,
>> struct virtio_shm_region *region, u8 id);
>> int (*disable_vq_and_reset)(struct virtqueue *vq);
>> @@ -210,14 +230,39 @@ static inline bool virtio_has_dma_quirk(const struct
>> virtio_device *vdev)
>> return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM);
>> }
>>
>> +static inline
>> +int virtio_find_vqs_info(struct virtio_device *vdev, unsigned int nvqs,
>> + struct virtqueue *vqs[],
>> + struct virtqueue_info vqs_info[],
>> + struct irq_affinity *desc)
>> +{
>> + return vdev->config->find_vqs_info(vdev, nvqs, vqs, vqs_info, desc);
>> +}
>> +
>> static inline
>> int virtio_find_vqs_ctx(struct virtio_device *vdev, unsigned nvqs,
>> struct virtqueue *vqs[], vq_callback_t *callbacks[],
>> const char * const names[], const bool *ctx,
>> struct irq_affinity *desc)
>> {
>> - return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names, ctx,
>> - desc);
>> + struct virtqueue_info *vqs_info;
>> + int err, i;
>> +
>> + if (!vdev->config->find_vqs_info)
>> + return vdev->config->find_vqs(vdev, nvqs, vqs, callbacks,
>> + names, ctx, desc);
>> +
>> + vqs_info = kmalloc_array(nvqs, sizeof(*vqs_info), GFP_KERNEL);
>> + if (!vqs_info)
>> + return -ENOMEM;
>> + for (i = 0; i < nvqs; i++) {
>> + vqs_info[i].name = names[i];
>> + vqs_info[i].callback = callbacks[i];
>> + vqs_info[i].ctx = ctx ? ctx[i] : false;
>> + }
>> + err = virtio_find_vqs_info(vdev, nvqs, vqs, vqs_info, desc);
>> + kfree(vqs_info);
>> + return err;
>> }
>>
>> static inline
>> --
>> 2.45.2
>
