1 /*
2 * Internal Header for the Direct Rendering Manager
3 *
4 * Copyright 2018 Intel Corporation
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
15 * Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26 #ifndef _DRM_UTIL_H_
27 #define _DRM_UTIL_H_
28
29 /**
30 * DOC: drm utils
31 *
32 * Macros and inline functions that does not naturally belong in other places
33 */
34
35 #include <linux/interrupt.h>
36 #include <linux/kgdb.h>
37 #include <linux/preempt.h>
38 #include <linux/smp.h>
39
40 /*
41 * Use EXPORT_SYMBOL_FOR_TESTS_ONLY() for functions that shall
42 * only be visible for drmselftests.
43 */
44 #if defined(CONFIG_DRM_DEBUG_SELFTEST_MODULE)
45 #define EXPORT_SYMBOL_FOR_TESTS_ONLY(x) EXPORT_SYMBOL(x)
46 #else
47 #define EXPORT_SYMBOL_FOR_TESTS_ONLY(x)
48 #endif
49
50 /**
51 * for_each_if - helper for handling conditionals in various for_each macros
52 * @condition: The condition to check
53 *
54 * Typical use::
55 *
56 * #define for_each_foo_bar(x, y) \'
57 * list_for_each_entry(x, y->list, head) \'
58 * for_each_if(x->something == SOMETHING)
59 *
60 * The for_each_if() macro makes the use of for_each_foo_bar() less error
61 * prone.
62 */
63 #define for_each_if(condition) if (!(condition)) {} else
64
65 /**
66 * drm_can_sleep - returns true if currently okay to sleep
67 *
68 * This function shall not be used in new code.
69 * The check for running in atomic context may not work - see linux/preempt.h.
70 *
71 * FIXME: All users of drm_can_sleep should be removed (see todo.rst)
72 *
73 * Returns:
74 * False if kgdb is active, we are in atomic context or irqs are disabled.
75 */
76 static inline bool drm_can_sleep(void)
77 {
78 if (in_atomic() || in_dbg_master() || irqs_disabled())
79 return false;
80 return true;
81 }
82
83 #endif