1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017 The Linux Foundation. All rights reserved.
3  */
4 
5 #include <linux/kref.h>
6 #include <linux/uaccess.h>
7 
8 #include "msm_gpu.h"
9 
10 void msm_submitqueue_destroy(struct kref *kref)
11 {
12 	struct msm_gpu_submitqueue *queue = container_of(kref,
13 		struct msm_gpu_submitqueue, ref);
14 
15 	kfree(queue);
16 }
17 
18 struct msm_gpu_submitqueue *msm_submitqueue_get(struct msm_file_private *ctx,
19 		u32 id)
20 {
21 	struct msm_gpu_submitqueue *entry;
22 
23 	if (!ctx)
24 		return NULL;
25 
26 	read_lock(&ctx->queuelock);
27 
28 	list_for_each_entry(entry, &ctx->submitqueues, node) {
29 		if (entry->id == id) {
30 			kref_get(&entry->ref);
31 			read_unlock(&ctx->queuelock);
32 
33 			return entry;
34 		}
35 	}
36 
37 	read_unlock(&ctx->queuelock);
38 	return NULL;
39 }
40 
41 void msm_submitqueue_close(struct msm_file_private *ctx)
42 {
43 	struct msm_gpu_submitqueue *entry, *tmp;
44 
45 	if (!ctx)
46 		return;
47 
48 	/*
49 	 * No lock needed in close and there won't
50 	 * be any more user ioctls coming our way
51 	 */
52 	list_for_each_entry_safe(entry, tmp, &ctx->submitqueues, node)
53 		msm_submitqueue_put(entry);
54 }
55 
56 int msm_submitqueue_create(struct drm_device *drm, struct msm_file_private *ctx,
57 		u32 prio, u32 flags, u32 *id)
58 {
59 	struct msm_drm_private *priv = drm->dev_private;
60 	struct msm_gpu_submitqueue *queue;
61 
62 	if (!ctx)
63 		return -ENODEV;
64 
65 	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
66 
67 	if (!queue)
68 		return -ENOMEM;
69 
70 	kref_init(&queue->ref);
71 	queue->flags = flags;
72 
73 	if (priv->gpu) {
74 		if (prio >= priv->gpu->nr_rings) {
75 			kfree(queue);
76 			return -EINVAL;
77 		}
78 
79 		queue->prio = prio;
80 	}
81 
82 	write_lock(&ctx->queuelock);
83 
84 	queue->id = ctx->queueid++;
85 
86 	if (id)
87 		*id = queue->id;
88 
89 	list_add_tail(&queue->node, &ctx->submitqueues);
90 
91 	write_unlock(&ctx->queuelock);
92 
93 	return 0;
94 }
95 
96 int msm_submitqueue_init(struct drm_device *drm, struct msm_file_private *ctx)
97 {
98 	struct msm_drm_private *priv = drm->dev_private;
99 	int default_prio;
100 
101 	if (!ctx)
102 		return 0;
103 
104 	/*
105 	 * Select priority 2 as the "default priority" unless nr_rings is less
106 	 * than 2 and then pick the lowest pirority
107 	 */
108 	default_prio = priv->gpu ?
109 		clamp_t(uint32_t, 2, 0, priv->gpu->nr_rings - 1) : 0;
110 
111 	INIT_LIST_HEAD(&ctx->submitqueues);
112 
113 	rwlock_init(&ctx->queuelock);
114 
115 	return msm_submitqueue_create(drm, ctx, default_prio, 0, NULL);
116 }
117 
118 static int msm_submitqueue_query_faults(struct msm_gpu_submitqueue *queue,
119 		struct drm_msm_submitqueue_query *args)
120 {
121 	size_t size = min_t(size_t, args->len, sizeof(queue->faults));
122 	int ret;
123 
124 	/* If a zero length was passed in, return the data size we expect */
125 	if (!args->len) {
126 		args->len = sizeof(queue->faults);
127 		return 0;
128 	}
129 
130 	/* Set the length to the actual size of the data */
131 	args->len = size;
132 
133 	ret = copy_to_user(u64_to_user_ptr(args->data), &queue->faults, size);
134 
135 	return ret ? -EFAULT : 0;
136 }
137 
138 int msm_submitqueue_query(struct drm_device *drm, struct msm_file_private *ctx,
139 		struct drm_msm_submitqueue_query *args)
140 {
141 	struct msm_gpu_submitqueue *queue;
142 	int ret = -EINVAL;
143 
144 	if (args->pad)
145 		return -EINVAL;
146 
147 	queue = msm_submitqueue_get(ctx, args->id);
148 	if (!queue)
149 		return -ENOENT;
150 
151 	if (args->param == MSM_SUBMITQUEUE_PARAM_FAULTS)
152 		ret = msm_submitqueue_query_faults(queue, args);
153 
154 	msm_submitqueue_put(queue);
155 
156 	return ret;
157 }
158 
159 int msm_submitqueue_remove(struct msm_file_private *ctx, u32 id)
160 {
161 	struct msm_gpu_submitqueue *entry;
162 
163 	if (!ctx)
164 		return 0;
165 
166 	/*
167 	 * id 0 is the "default" queue and can't be destroyed
168 	 * by the user
169 	 */
170 	if (!id)
171 		return -ENOENT;
172 
173 	write_lock(&ctx->queuelock);
174 
175 	list_for_each_entry(entry, &ctx->submitqueues, node) {
176 		if (entry->id == id) {
177 			list_del(&entry->node);
178 			write_unlock(&ctx->queuelock);
179 
180 			msm_submitqueue_put(entry);
181 			return 0;
182 		}
183 	}
184 
185 	write_unlock(&ctx->queuelock);
186 	return -ENOENT;
187 }
188 
189