1// SPDX-License-Identifier: GPL-2.0 OR MIT
 2/*
 3 * Copyright 2014-2022 Advanced Micro Devices, Inc.
 4 *
 5 * Permission is hereby granted, free of charge, to any person obtaining a
 6 * copy of this software and associated documentation files (the "Software"),
 7 * to deal in the Software without restriction, including without limitation
 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 */
23
 
24#include <linux/types.h>
25#include "kfd_priv.h"
26#include "amdgpu_ids.h"
27
28static unsigned int pasid_bits = 16;
29static bool pasids_allocated; /* = false */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
30
31bool kfd_set_pasid_limit(unsigned int new_limit)
32{
33	if (new_limit < 2)
34		return false;
 
 
 
 
 
 
 
 
35
36	if (new_limit < (1U << pasid_bits)) {
37		if (pasids_allocated)
38			/* We've already allocated user PASIDs, too late to
39			 * change the limit
40			 */
41			return false;
42
43		while (new_limit < (1U << pasid_bits))
44			pasid_bits--;
45	}
46
47	return true;
48}
49
50unsigned int kfd_get_pasid_limit(void)
51{
52	return 1U << pasid_bits;
53}
54
55u32 kfd_pasid_alloc(void)
56{
57	int r = amdgpu_pasid_alloc(pasid_bits);
58
59	if (r > 0) {
60		pasids_allocated = true;
61		return r;
62	}
63
64	return 0;
 
 
 
 
 
 
 
 
65}
66
67void kfd_pasid_free(u32 pasid)
68{
69	amdgpu_pasid_free(pasid);
 
70}

 
 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}