Re: [PATCH v10 03/14] drm/amdgpu: add new IOCTL for usermode queue

["Sharma, Shashank" <shashank.sharma@amd.com>]

On 02/05/2024 23:25, Alex Deucher wrote:
> On Thu, May 2, 2024 at 1:27 PM Shashank Sharma <shashank.sharma@amd.com> wrote:
>> This patch adds:
>> - A new IOCTL function to create and destroy
>> - A new structure to keep all the user queue data in one place.
>> - A function to generate unique index for the queue.
>>
>> V1: Worked on review comments from RFC patch series:
>>    - Alex: Keep a list of queues, instead of single queue per process.
>>    - Christian: Use the queue manager instead of global ptrs,
>>             Don't keep the queue structure in amdgpu_ctx
>>
>> V2: Worked on review comments:
>>   - Christian:
>>     - Formatting of text
>>     - There is no need for queuing of userqueues, with idr in place
>>   - Alex:
>>     - Remove use_doorbell, its unnecessary
>>     - Reuse amdgpu_mqd_props for saving mqd fields
>>
>>   - Code formatting and re-arrangement
>>
>> V3:
>>   - Integration with doorbell manager
>>
>> V4:
>>   - Accommodate MQD union related changes in UAPI (Alex)
>>   - Do not set the queue size twice (Bas)
>>
>> V5:
>>   - Remove wrapper functions for queue indexing (Christian)
>>   - Do not save the queue id/idr in queue itself (Christian)
>>   - Move the idr allocation in the IP independent generic space
>>    (Christian)
>>
>> V6:
>>   - Check the validity of input IP type (Christian)
>>
>> V7:
>>   - Move uq_func from uq_mgr to adev (Alex)
>>   - Add missing free(queue) for error cases (Yifan)
>>
>> V9:
>>   - Rebase
>>
>> V10: Addressed review comments from Christian, and added R-B:
>>   - Do not initialize the local variable
>>   - Convert DRM_ERROR to DEBUG.
>>
>> Cc: Alex Deucher <alexander.deucher@amd.com>
>> Cc: Christian Koenig <christian.koenig@amd.com>
>> Reviewed-by: Christian Koenig <christian.koenig@amd.com>
>> Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c       |   1 +
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c | 121 ++++++++++++++++++
>>   .../gpu/drm/amd/include/amdgpu_userqueue.h    |   2 +
>>   3 files changed, 124 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> index b52442e2d04a..551e13693100 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> @@ -2929,6 +2929,7 @@ const struct drm_ioctl_desc amdgpu_ioctls_kms[] = {
>>          DRM_IOCTL_DEF_DRV(AMDGPU_GEM_VA, amdgpu_gem_va_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
>>          DRM_IOCTL_DEF_DRV(AMDGPU_GEM_OP, amdgpu_gem_op_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
>>          DRM_IOCTL_DEF_DRV(AMDGPU_GEM_USERPTR, amdgpu_gem_userptr_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
>> +       DRM_IOCTL_DEF_DRV(AMDGPU_USERQ, amdgpu_userq_ioctl, DRM_AUTH|DRM_RENDER_ALLOW),
>>   };
>>
>>   static const struct drm_driver amdgpu_kms_driver = {
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> index effc0c7c02cf..ce9b25b82e94 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userqueue.c
>> @@ -23,6 +23,127 @@
>>    */
>>
>>   #include "amdgpu.h"
>> +#include "amdgpu_vm.h"
>> +#include "amdgpu_userqueue.h"
>> +
>> +static struct amdgpu_usermode_queue *
>> +amdgpu_userqueue_find(struct amdgpu_userq_mgr *uq_mgr, int qid)
>> +{
>> +       return idr_find(&uq_mgr->userq_idr, qid);
>> +}
>> +
>> +static int
>> +amdgpu_userqueue_destroy(struct drm_file *filp, int queue_id)
>> +{
>> +       struct amdgpu_fpriv *fpriv = filp->driver_priv;
>> +       struct amdgpu_userq_mgr *uq_mgr = &fpriv->userq_mgr;
>> +       struct amdgpu_device *adev = uq_mgr->adev;
>> +       const struct amdgpu_userq_funcs *uq_funcs;
>> +       struct amdgpu_usermode_queue *queue;
>> +
>> +       mutex_lock(&uq_mgr->userq_mutex);
>> +
>> +       queue = amdgpu_userqueue_find(uq_mgr, queue_id);
>> +       if (!queue) {
>> +               DRM_DEBUG_DRIVER("Invalid queue id to destroy\n");
>> +               mutex_unlock(&uq_mgr->userq_mutex);
>> +               return -EINVAL;
>> +       }
>> +
>> +       uq_funcs = adev->userq_funcs[queue->queue_type];
>> +       uq_funcs->mqd_destroy(uq_mgr, queue);
>> +       idr_remove(&uq_mgr->userq_idr, queue_id);
>> +       kfree(queue);
>> +
>> +       mutex_unlock(&uq_mgr->userq_mutex);
>> +       return 0;
>> +}
>> +
>> +static int
>> +amdgpu_userqueue_create(struct drm_file *filp, union drm_amdgpu_userq *args)
>> +{
>> +       struct amdgpu_fpriv *fpriv = filp->driver_priv;
>> +       struct amdgpu_userq_mgr *uq_mgr = &fpriv->userq_mgr;
>> +       struct amdgpu_device *adev = uq_mgr->adev;
>> +       const struct amdgpu_userq_funcs *uq_funcs;
>> +       struct amdgpu_usermode_queue *queue;
>> +       int qid, r = 0;
>> +
>> +       /* Usermode queues are only supported for GFX/SDMA engines as of now */
>> +       if (args->in.ip_type != AMDGPU_HW_IP_GFX) {
>> +               DRM_ERROR("Usermode queue doesn't support IP type %u\n", args->in.ip_type);
>> +               return -EINVAL;
>> +       }
>> +
>> +       mutex_lock(&uq_mgr->userq_mutex);
>> +
>> +       uq_funcs = adev->userq_funcs[args->in.ip_type];
>> +       if (!uq_funcs) {
>> +               DRM_ERROR("Usermode queue is not supported for this IP (%u)\n", args->in.ip_type);
>> +               r = -EINVAL;
>> +               goto unlock;
>> +       }
>> +
>> +       queue = kzalloc(sizeof(struct amdgpu_usermode_queue), GFP_KERNEL);
>> +       if (!queue) {
>> +               DRM_ERROR("Failed to allocate memory for queue\n");
>> +               r = -ENOMEM;
>> +               goto unlock;
>> +       }
>> +       queue->doorbell_handle = args->in.doorbell_handle;
>> +       queue->doorbell_index = args->in.doorbell_offset;
>> +       queue->queue_type = args->in.ip_type;
> Validate that ip_type is valid here.
It has been validated at the entry of the function.
>> +       queue->flags = args->in.flags;
> Validate that flags is 0 until we actually implement support for the flags.

Noted

- Shashank

>
>> +       queue->vm = &fpriv->vm;
>> +
>> +       r = uq_funcs->mqd_create(uq_mgr, &args->in, queue);
>> +       if (r) {
>> +               DRM_ERROR("Failed to create Queue\n");
>> +               kfree(queue);
>> +               goto unlock;
>> +       }
>> +
>> +       qid = idr_alloc(&uq_mgr->userq_idr, queue, 1, AMDGPU_MAX_USERQ_COUNT, GFP_KERNEL);
>> +       if (qid < 0) {
>> +               DRM_ERROR("Failed to allocate a queue id\n");
>> +               uq_funcs->mqd_destroy(uq_mgr, queue);
>> +               kfree(queue);
>> +               r = -ENOMEM;
>> +               goto unlock;
>> +       }
>> +       args->out.queue_id = qid;
>> +
>> +unlock:
>> +       mutex_unlock(&uq_mgr->userq_mutex);
>> +       return r;
>> +}
>> +
>> +int amdgpu_userq_ioctl(struct drm_device *dev, void *data,
>> +                      struct drm_file *filp)
>> +{
>> +       union drm_amdgpu_userq *args = data;
>> +       int r;
>> +
>> +       switch (args->in.op) {
>> +       case AMDGPU_USERQ_OP_CREATE:
>> +               r = amdgpu_userqueue_create(filp, args);
>> +               if (r)
>> +                       DRM_ERROR("Failed to create usermode queue\n");
>> +               break;
>> +
>> +       case AMDGPU_USERQ_OP_FREE:
>> +               r = amdgpu_userqueue_destroy(filp, args->in.queue_id);
>> +               if (r)
>> +                       DRM_ERROR("Failed to destroy usermode queue\n");
>> +               break;
>> +
>> +       default:
>> +               DRM_DEBUG_DRIVER("Invalid user queue op specified: %d\n", args->in.op);
>> +               return -EINVAL;
>> +       }
>> +
>> +       return r;
>> +}
>>
>>   int amdgpu_userq_mgr_init(struct amdgpu_userq_mgr *userq_mgr, struct amdgpu_device *adev)
>>   {
>> diff --git a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> index 93ebe4b61682..b739274c72e1 100644
>> --- a/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> +++ b/drivers/gpu/drm/amd/include/amdgpu_userqueue.h
>> @@ -54,6 +54,8 @@ struct amdgpu_userq_mgr {
>>          struct amdgpu_device            *adev;
>>   };
>>
>> +int amdgpu_userq_ioctl(struct drm_device *dev, void *data, struct drm_file *filp);
>> +
>>   int amdgpu_userq_mgr_init(struct amdgpu_userq_mgr *userq_mgr, struct amdgpu_device *adev);
>>
>>   void amdgpu_userq_mgr_fini(struct amdgpu_userq_mgr *userq_mgr);
>> --
>> 2.43.2
>>