1/*
 2 * Copyright 2014 Advanced Micro Devices, Inc.
 3 *
 4 * Permission is hereby granted, free of charge, to any person obtaining a
 5 * copy of this software and associated documentation files (the "Software"),
 6 * to deal in the Software without restriction, including without limitation
 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 8 * and/or sell copies of the Software, and to permit persons to whom the
 9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 */
22
23#include <linux/slab.h>
24#include <linux/types.h>
25#include "kfd_priv.h"
26
27static unsigned long *pasid_bitmap;
28static unsigned int pasid_limit;
29static DEFINE_MUTEX(pasid_mutex);
30
31int kfd_pasid_init(void)
32{
33	pasid_limit = KFD_MAX_NUM_OF_PROCESSES;
34
35	pasid_bitmap = kcalloc(BITS_TO_LONGS(pasid_limit), sizeof(long), GFP_KERNEL);
36	if (!pasid_bitmap)
37		return -ENOMEM;
38
39	set_bit(0, pasid_bitmap); /* PASID 0 is reserved. */
40
41	return 0;
42}
43
44void kfd_pasid_exit(void)
45{
46	kfree(pasid_bitmap);
47}
48
49bool kfd_set_pasid_limit(unsigned int new_limit)
50{
51	if (new_limit < pasid_limit) {
52		bool ok;
53
54		mutex_lock(&pasid_mutex);
 
 
 
 
 
55
56		/* ensure that no pasids >= new_limit are in-use */
57		ok = (find_next_bit(pasid_bitmap, pasid_limit, new_limit) ==
58								pasid_limit);
59		if (ok)
60			pasid_limit = new_limit;
61
62		mutex_unlock(&pasid_mutex);
63
64		return ok;
65	}
66
67	return true;
68}
69
70inline unsigned int kfd_get_pasid_limit(void)
71{
72	return pasid_limit;
73}
74
75unsigned int kfd_pasid_alloc(void)
76{
77	unsigned int found;
78
79	mutex_lock(&pasid_mutex);
 
 
 
 
 
 
 
 
 
 
 
80
81	found = find_first_zero_bit(pasid_bitmap, pasid_limit);
82	if (found == pasid_limit)
83		found = 0;
84	else
85		set_bit(found, pasid_bitmap);
86
87	mutex_unlock(&pasid_mutex);
88
89	return found;
90}
91
92void kfd_pasid_free(unsigned int pasid)
93{
94	BUG_ON(pasid == 0 || pasid >= pasid_limit);
95	clear_bit(pasid, pasid_bitmap);
96}

 1/*
 2 * Copyright 2014 Advanced Micro Devices, Inc.
 3 *
 4 * Permission is hereby granted, free of charge, to any person obtaining a
 5 * copy of this software and associated documentation files (the "Software"),
 6 * to deal in the Software without restriction, including without limitation
 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 8 * and/or sell copies of the Software, and to permit persons to whom the
 9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 */
22
 
23#include <linux/types.h>
24#include "kfd_priv.h"
25
26static unsigned int pasid_bits = 16;
27static const struct kfd2kgd_calls *kfd2kgd;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
28
29bool kfd_set_pasid_limit(unsigned int new_limit)
30{
31	if (new_limit < 2)
32		return false;
33
34	if (new_limit < (1U << pasid_bits)) {
35		if (kfd2kgd)
36			/* We've already allocated user PASIDs, too late to
37			 * change the limit
38			 */
39			return false;
40
41		while (new_limit < (1U << pasid_bits))
42			pasid_bits--;
 
 
 
 
 
 
 
43	}
44
45	return true;
46}
47
48unsigned int kfd_get_pasid_limit(void)
49{
50	return 1U << pasid_bits;
51}
52
53unsigned int kfd_pasid_alloc(void)
54{
55	int r;
56
57	/* Find the first best KFD device for calling KGD */
58	if (!kfd2kgd) {
59		struct kfd_dev *dev = NULL;
60		unsigned int i = 0;
61
62		while ((kfd_topology_enum_kfd_devices(i, &dev)) == 0) {
63			if (dev && dev->kfd2kgd) {
64				kfd2kgd = dev->kfd2kgd;
65				break;
66			}
67			i++;
68		}
69
70		if (!kfd2kgd)
71			return false;
72	}
 
 
73
74	r = kfd2kgd->alloc_pasid(pasid_bits);
75
76	return r > 0 ? r : 0;
77}
78
79void kfd_pasid_free(unsigned int pasid)
80{
81	if (kfd2kgd)
82		kfd2kgd->free_pasid(pasid);
83}