OMAPDSS: VENC: fix NULL pointer dereference in DSS2 VENC sysfs debug attr on OMAP4
[zen-stable.git] / drivers / gpu / drm / ttm / ttm_bo_manager.c
blob038e947d00f986ef987ef914fd8432f2202c25f3
1 /**************************************************************************
3 * Copyright (c) 2007-2010 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
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:
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.
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.
26 **************************************************************************/
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
31 #include "ttm/ttm_module.h"
32 #include "ttm/ttm_bo_driver.h"
33 #include "ttm/ttm_placement.h"
34 #include "drm_mm.h"
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <linux/module.h>
39 /**
40 * Currently we use a spinlock for the lock, but a mutex *may* be
41 * more appropriate to reduce scheduling latency if the range manager
42 * ends up with very fragmented allocation patterns.
45 struct ttm_range_manager {
46 struct drm_mm mm;
47 spinlock_t lock;
50 static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
51 struct ttm_buffer_object *bo,
52 struct ttm_placement *placement,
53 struct ttm_mem_reg *mem)
55 struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
56 struct drm_mm *mm = &rman->mm;
57 struct drm_mm_node *node = NULL;
58 unsigned long lpfn;
59 int ret;
61 lpfn = placement->lpfn;
62 if (!lpfn)
63 lpfn = man->size;
64 do {
65 ret = drm_mm_pre_get(mm);
66 if (unlikely(ret))
67 return ret;
69 spin_lock(&rman->lock);
70 node = drm_mm_search_free_in_range(mm,
71 mem->num_pages, mem->page_alignment,
72 placement->fpfn, lpfn, 1);
73 if (unlikely(node == NULL)) {
74 spin_unlock(&rman->lock);
75 return 0;
77 node = drm_mm_get_block_atomic_range(node, mem->num_pages,
78 mem->page_alignment,
79 placement->fpfn,
80 lpfn);
81 spin_unlock(&rman->lock);
82 } while (node == NULL);
84 mem->mm_node = node;
85 mem->start = node->start;
86 return 0;
89 static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man,
90 struct ttm_mem_reg *mem)
92 struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
94 if (mem->mm_node) {
95 spin_lock(&rman->lock);
96 drm_mm_put_block(mem->mm_node);
97 spin_unlock(&rman->lock);
98 mem->mm_node = NULL;
102 static int ttm_bo_man_init(struct ttm_mem_type_manager *man,
103 unsigned long p_size)
105 struct ttm_range_manager *rman;
106 int ret;
108 rman = kzalloc(sizeof(*rman), GFP_KERNEL);
109 if (!rman)
110 return -ENOMEM;
112 ret = drm_mm_init(&rman->mm, 0, p_size);
113 if (ret) {
114 kfree(rman);
115 return ret;
118 spin_lock_init(&rman->lock);
119 man->priv = rman;
120 return 0;
123 static int ttm_bo_man_takedown(struct ttm_mem_type_manager *man)
125 struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
126 struct drm_mm *mm = &rman->mm;
128 spin_lock(&rman->lock);
129 if (drm_mm_clean(mm)) {
130 drm_mm_takedown(mm);
131 spin_unlock(&rman->lock);
132 kfree(rman);
133 man->priv = NULL;
134 return 0;
136 spin_unlock(&rman->lock);
137 return -EBUSY;
140 static void ttm_bo_man_debug(struct ttm_mem_type_manager *man,
141 const char *prefix)
143 struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
145 spin_lock(&rman->lock);
146 drm_mm_debug_table(&rman->mm, prefix);
147 spin_unlock(&rman->lock);
150 const struct ttm_mem_type_manager_func ttm_bo_manager_func = {
151 ttm_bo_man_init,
152 ttm_bo_man_takedown,
153 ttm_bo_man_get_node,
154 ttm_bo_man_put_node,
155 ttm_bo_man_debug
157 EXPORT_SYMBOL(ttm_bo_manager_func);