[PATCH v4 6/6] drm/amdgpu: add MODIFY operation for compute queues

[Jesse.Zhang <Jesse.Zhang@amd.com>]

Implement the AMDGPU_USERQ_OP_MODIFY ioctl operation to enable runtime updates
of compute queues.

v2: move queue size validate to a separate patch
    remove the check for AMDGPU_HW_IP_COMPUTE  (Alex)

Suggested-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jesse Zhang <jesse.zhang@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 61 +++++++++++++++++++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h |  3 ++
 include/uapi/drm/amdgpu_drm.h             |  1 +
 3 files changed, 65 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
index 256ceca6d429..3003aba22e1d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c
@@ -837,6 +837,7 @@ static int amdgpu_userq_input_args_validate(struct drm_device *dev,
 
 	switch (args->in.op) {
 	case AMDGPU_USERQ_OP_CREATE:
+	case AMDGPU_USERQ_OP_MODIFY:
 		if (args->in.flags & ~(AMDGPU_USERQ_CREATE_FLAGS_QUEUE_PRIORITY_MASK |
 				       AMDGPU_USERQ_CREATE_FLAGS_QUEUE_SECURE))
 			return -EINVAL;
@@ -901,6 +902,60 @@ bool amdgpu_userq_enabled(struct drm_device *dev)
 	return false;
 }
 
+static int amdgpu_modify_queue(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;
+	struct amdgpu_usermode_queue *queue;
+	const struct amdgpu_userq_funcs *userq_funcs;
+	int r;
+
+	mutex_lock(&uq_mgr->userq_mutex);
+	queue = amdgpu_userq_find(uq_mgr, args->in.queue_id);
+	if (!queue) {
+		drm_file_err(uq_mgr->file, "Queue %u not found\n", args->in.queue_id);
+		r = -EINVAL;
+		goto unlock;
+	}
+
+	userq_funcs = adev->userq_funcs[queue->queue_type];
+
+	/*
+	 * Unmap the queue if it's mapped or preempted to ensure a clean update.
+	 * If the queue is already unmapped or hung, we skip this step.
+	 */
+	if (queue->state == AMDGPU_USERQ_STATE_MAPPED ||
+	    queue->state == AMDGPU_USERQ_STATE_PREEMPTED) {
+		r = amdgpu_userq_unmap_helper(queue);
+		if (r) {
+			drm_file_err(uq_mgr->file, "Failed to unmap queue %llu\n",
+					queue->doorbell_index);
+			goto unlock;
+		}
+	}
+
+	r = userq_funcs->mqd_update(queue, &args->in);
+	if (r)
+		goto unlock;
+	/*
+	 * If the queue is considered active (has valid size, address, and percentage),
+	 * we attempt to map it. This effectively starts the queue or restarts it
+	 * if it was previously running.
+	 */
+	if (AMDGPU_USERQ_IS_ACTIVE(queue)) {
+		r = amdgpu_userq_map_helper(queue);
+		if (r)
+			drm_file_err(uq_mgr->file, "Failed to remap queue %llu after update\n",
+				queue->doorbell_index);
+	}
+
+unlock:
+	mutex_unlock(&uq_mgr->userq_mutex);
+
+	return r;
+}
+
 int amdgpu_userq_ioctl(struct drm_device *dev, void *data,
 		       struct drm_file *filp)
 {
@@ -920,6 +975,12 @@ int amdgpu_userq_ioctl(struct drm_device *dev, void *data,
 			drm_file_err(filp, "Failed to create usermode queue\n");
 		break;
 
+
+	case AMDGPU_USERQ_OP_MODIFY:
+		r = amdgpu_modify_queue(filp, args);
+		if (r)
+			drm_file_err(filp, "Failed to modify usermode queue\n");
+		break;
 	case AMDGPU_USERQ_OP_FREE:
 		r = amdgpu_userq_destroy(filp, args->in.queue_id);
 		if (r)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h
index 833468b58603..7cd1ea94e368 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h
@@ -31,6 +31,9 @@
 #define to_ev_fence(f) container_of(f, struct amdgpu_eviction_fence, base)
 #define uq_mgr_to_fpriv(u) container_of(u, struct amdgpu_fpriv, userq_mgr)
 #define work_to_uq_mgr(w, name) container_of(w, struct amdgpu_userq_mgr, name)
+#define AMDGPU_USERQ_IS_ACTIVE(q) ((q)->userq_prop->queue_size > 0 &&  \
+                           (q)->userq_prop->hqd_base_gpu_addr != 0 &&  \
+                           (q)->userq_prop->queue_percentage > 0)
 
 enum amdgpu_userq_state {
 	AMDGPU_USERQ_STATE_UNMAPPED = 0,
diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
index c52949ea8c1e..aa9b31578c6b 100644
--- a/include/uapi/drm/amdgpu_drm.h
+++ b/include/uapi/drm/amdgpu_drm.h
@@ -330,6 +330,7 @@ union drm_amdgpu_ctx {
 /* user queue IOCTL operations */
 #define AMDGPU_USERQ_OP_CREATE	1
 #define AMDGPU_USERQ_OP_FREE	2
+#define AMDGPU_USERQ_OP_MODIFY 3
 
 /* queue priority levels */
 /* low < normal low < normal high < high */
-- 
2.49.0