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 			return -EINVAL;
76 
77 		queue->prio = prio;
78 	}
79 
80 	write_lock(&ctx->queuelock);
81 
82 	queue->id = ctx->queueid++;
83 
84 	if (id)
85 		*id = queue->id;
86 
87 	list_add_tail(&queue->node, &ctx->submitqueues);
88 
89 	write_unlock(&ctx->queuelock);
90 
91 	return 0;
92 }
93 
94 int msm_submitqueue_init(struct drm_device *drm, struct msm_file_private *ctx)
95 {
96 	struct msm_drm_private *priv = drm->dev_private;
97 	int default_prio;
98 
99 	if (!ctx)
100 		return 0;
101 
102 	/*
103 	 * Select priority 2 as the "default priority" unless nr_rings is less
104 	 * than 2 and then pick the lowest pirority
105 	 */
106 	default_prio = priv->gpu ?
107 		clamp_t(uint32_t, 2, 0, priv->gpu->nr_rings - 1) : 0;
108 
109 	INIT_LIST_HEAD(&ctx->submitqueues);
110 
111 	rwlock_init(&ctx->queuelock);
112 
113 	return msm_submitqueue_create(drm, ctx, default_prio, 0, NULL);
114 }
115 
116 static int msm_submitqueue_query_faults(struct msm_gpu_submitqueue *queue,
117 		struct drm_msm_submitqueue_query *args)
118 {
119 	size_t size = min_t(size_t, args->len, sizeof(queue->faults));
120 	int ret;
121 
122 	/* If a zero length was passed in, return the data size we expect */
123 	if (!args->len) {
124 		args->len = sizeof(queue->faults);
125 		return 0;
126 	}
127 
128 	/* Set the length to the actual size of the data */
129 	args->len = size;
130 
131 	ret = copy_to_user(u64_to_user_ptr(args->data), &queue->faults, size);
132 
133 	return ret ? -EFAULT : 0;
134 }
135 
136 int msm_submitqueue_query(struct drm_device *drm, struct msm_file_private *ctx,
137 		struct drm_msm_submitqueue_query *args)
138 {
139 	struct msm_gpu_submitqueue *queue;
140 	int ret = -EINVAL;
141 
142 	if (args->pad)
143 		return -EINVAL;
144 
145 	queue = msm_submitqueue_get(ctx, args->id);
146 	if (!queue)
147 		return -ENOENT;
148 
149 	if (args->param == MSM_SUBMITQUEUE_PARAM_FAULTS)
150 		ret = msm_submitqueue_query_faults(queue, args);
151 
152 	msm_submitqueue_put(queue);
153 
154 	return ret;
155 }
156 
157 int msm_submitqueue_remove(struct msm_file_private *ctx, u32 id)
158 {
159 	struct msm_gpu_submitqueue *entry;
160 
161 	if (!ctx)
162 		return 0;
163 
164 	/*
165 	 * id 0 is the "default" queue and can't be destroyed
166 	 * by the user
167 	 */
168 	if (!id)
169 		return -ENOENT;
170 
171 	write_lock(&ctx->queuelock);
172 
173 	list_for_each_entry(entry, &ctx->submitqueues, node) {
174 		if (entry->id == id) {
175 			list_del(&entry->node);
176 			write_unlock(&ctx->queuelock);
177 
178 			msm_submitqueue_put(entry);
179 			return 0;
180 		}
181 	}
182 
183 	write_unlock(&ctx->queuelock);
184 	return -ENOENT;
185 }
186 
187