1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /**************************************************************************
3  *
4  * Copyright 2007-2010 VMware, Inc., Palo Alto, CA., USA
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 /*
28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29  */
30 
31 #include "vmwgfx_drv.h"
32 #include <drm/ttm/ttm_bo_driver.h>
33 #include <drm/ttm/ttm_placement.h>
34 #include <linux/idr.h>
35 #include <linux/spinlock.h>
36 #include <linux/kernel.h>
37 
38 struct vmwgfx_gmrid_man {
39 	struct ttm_resource_manager manager;
40 	spinlock_t lock;
41 	struct ida gmr_ida;
42 	uint32_t max_gmr_ids;
43 	uint32_t max_gmr_pages;
44 	uint32_t used_gmr_pages;
45 };
46 
47 static struct vmwgfx_gmrid_man *to_gmrid_manager(struct ttm_resource_manager *man)
48 {
49 	return container_of(man, struct vmwgfx_gmrid_man, manager);
50 }
51 
52 static int vmw_gmrid_man_get_node(struct ttm_resource_manager *man,
53 				  struct ttm_buffer_object *bo,
54 				  const struct ttm_place *place,
55 				  struct ttm_resource **res)
56 {
57 	struct vmwgfx_gmrid_man *gman = to_gmrid_manager(man);
58 	int id;
59 
60 	*res = kmalloc(sizeof(**res), GFP_KERNEL);
61 	if (!*res)
62 		return -ENOMEM;
63 
64 	ttm_resource_init(bo, place, *res);
65 
66 	id = ida_alloc_max(&gman->gmr_ida, gman->max_gmr_ids - 1, GFP_KERNEL);
67 	if (id < 0)
68 		return id;
69 
70 	spin_lock(&gman->lock);
71 
72 	if (gman->max_gmr_pages > 0) {
73 		gman->used_gmr_pages += (*res)->num_pages;
74 		/*
75 		 * Because the graphics memory is a soft limit we can try to
76 		 * expand it instead of letting the userspace apps crash.
77 		 * We're just going to have a sane limit (half of RAM)
78 		 * on the number of MOB's that we create and will try to keep
79 		 * the system running until we reach that.
80 		 */
81 		if (unlikely(gman->used_gmr_pages > gman->max_gmr_pages)) {
82 			const unsigned long max_graphics_pages = totalram_pages() / 2;
83 			uint32_t new_max_pages = 0;
84 
85 			DRM_WARN("vmwgfx: mob memory overflow. Consider increasing guest RAM and graphicsMemory.\n");
86 			vmw_host_printf("vmwgfx, warning: mob memory overflow. Consider increasing guest RAM and graphicsMemory.\n");
87 
88 			if (gman->max_gmr_pages > (max_graphics_pages / 2)) {
89 				DRM_WARN("vmwgfx: guest requires more than half of RAM for graphics.\n");
90 				new_max_pages = max_graphics_pages;
91 			} else
92 				new_max_pages = gman->max_gmr_pages * 2;
93 			if (new_max_pages > gman->max_gmr_pages && new_max_pages >= gman->used_gmr_pages) {
94 				DRM_WARN("vmwgfx: increasing guest mob limits to %u kB.\n",
95 					 ((new_max_pages) << (PAGE_SHIFT - 10)));
96 
97 				gman->max_gmr_pages = new_max_pages;
98 			} else {
99 				char buf[256];
100 				snprintf(buf, sizeof(buf),
101 					 "vmwgfx, error: guest graphics is out of memory (mob limit at: %ukB).\n",
102 					 ((gman->max_gmr_pages) << (PAGE_SHIFT - 10)));
103 				vmw_host_printf(buf);
104 				DRM_WARN("%s", buf);
105 				goto nospace;
106 			}
107 		}
108 	}
109 
110 	(*res)->start = id;
111 
112 	spin_unlock(&gman->lock);
113 	return 0;
114 
115 nospace:
116 	gman->used_gmr_pages -= (*res)->num_pages;
117 	spin_unlock(&gman->lock);
118 	ida_free(&gman->gmr_ida, id);
119 	kfree(*res);
120 	return -ENOSPC;
121 }
122 
123 static void vmw_gmrid_man_put_node(struct ttm_resource_manager *man,
124 				   struct ttm_resource *res)
125 {
126 	struct vmwgfx_gmrid_man *gman = to_gmrid_manager(man);
127 
128 	ida_free(&gman->gmr_ida, res->start);
129 	spin_lock(&gman->lock);
130 	gman->used_gmr_pages -= res->num_pages;
131 	spin_unlock(&gman->lock);
132 	kfree(res);
133 }
134 
135 static const struct ttm_resource_manager_func vmw_gmrid_manager_func;
136 
137 int vmw_gmrid_man_init(struct vmw_private *dev_priv, int type)
138 {
139 	struct ttm_resource_manager *man;
140 	struct vmwgfx_gmrid_man *gman =
141 		kzalloc(sizeof(*gman), GFP_KERNEL);
142 
143 	if (unlikely(!gman))
144 		return -ENOMEM;
145 
146 	man = &gman->manager;
147 
148 	man->func = &vmw_gmrid_manager_func;
149 	/* TODO: This is most likely not correct */
150 	man->use_tt = true;
151 	ttm_resource_manager_init(man, 0);
152 	spin_lock_init(&gman->lock);
153 	gman->used_gmr_pages = 0;
154 	ida_init(&gman->gmr_ida);
155 
156 	switch (type) {
157 	case VMW_PL_GMR:
158 		gman->max_gmr_ids = dev_priv->max_gmr_ids;
159 		gman->max_gmr_pages = dev_priv->max_gmr_pages;
160 		break;
161 	case VMW_PL_MOB:
162 		gman->max_gmr_ids = VMWGFX_NUM_MOB;
163 		gman->max_gmr_pages = dev_priv->max_mob_pages;
164 		break;
165 	default:
166 		BUG();
167 	}
168 	ttm_set_driver_manager(&dev_priv->bdev, type, &gman->manager);
169 	ttm_resource_manager_set_used(man, true);
170 	return 0;
171 }
172 
173 void vmw_gmrid_man_fini(struct vmw_private *dev_priv, int type)
174 {
175 	struct ttm_resource_manager *man = ttm_manager_type(&dev_priv->bdev, type);
176 	struct vmwgfx_gmrid_man *gman = to_gmrid_manager(man);
177 
178 	ttm_resource_manager_set_used(man, false);
179 
180 	ttm_resource_manager_evict_all(&dev_priv->bdev, man);
181 
182 	ttm_resource_manager_cleanup(man);
183 
184 	ttm_set_driver_manager(&dev_priv->bdev, type, NULL);
185 	ida_destroy(&gman->gmr_ida);
186 	kfree(gman);
187 
188 }
189 
190 static const struct ttm_resource_manager_func vmw_gmrid_manager_func = {
191 	.alloc = vmw_gmrid_man_get_node,
192 	.free = vmw_gmrid_man_put_node,
193 };
194