xref: /openbmc/linux/drivers/gpu/drm/msm/msm_gem_vma.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2016 Red Hat
4  * Author: Rob Clark <robdclark@gmail.com>
5  */
6 
7 #include "msm_drv.h"
8 #include "msm_gem.h"
9 #include "msm_mmu.h"
10 
11 static void
12 msm_gem_address_space_destroy(struct kref *kref)
13 {
14 	struct msm_gem_address_space *aspace = container_of(kref,
15 			struct msm_gem_address_space, kref);
16 
17 	drm_mm_takedown(&aspace->mm);
18 	if (aspace->mmu)
19 		aspace->mmu->funcs->destroy(aspace->mmu);
20 	put_pid(aspace->pid);
21 	kfree(aspace);
22 }
23 
24 
25 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
26 {
27 	if (aspace)
28 		kref_put(&aspace->kref, msm_gem_address_space_destroy);
29 }
30 
31 struct msm_gem_address_space *
32 msm_gem_address_space_get(struct msm_gem_address_space *aspace)
33 {
34 	if (!IS_ERR_OR_NULL(aspace))
35 		kref_get(&aspace->kref);
36 
37 	return aspace;
38 }
39 
40 /* Actually unmap memory for the vma */
41 void msm_gem_purge_vma(struct msm_gem_address_space *aspace,
42 		struct msm_gem_vma *vma)
43 {
44 	unsigned size = vma->node.size << PAGE_SHIFT;
45 
46 	/* Print a message if we try to purge a vma in use */
47 	if (WARN_ON(vma->inuse > 0))
48 		return;
49 
50 	/* Don't do anything if the memory isn't mapped */
51 	if (!vma->mapped)
52 		return;
53 
54 	if (aspace->mmu)
55 		aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, size);
56 
57 	vma->mapped = false;
58 }
59 
60 /* Remove reference counts for the mapping */
61 void msm_gem_unmap_vma(struct msm_gem_address_space *aspace,
62 		struct msm_gem_vma *vma)
63 {
64 	if (!WARN_ON(!vma->iova))
65 		vma->inuse--;
66 }
67 
68 int
69 msm_gem_map_vma(struct msm_gem_address_space *aspace,
70 		struct msm_gem_vma *vma, int prot,
71 		struct sg_table *sgt, int npages)
72 {
73 	unsigned size = npages << PAGE_SHIFT;
74 	int ret = 0;
75 
76 	if (WARN_ON(!vma->iova))
77 		return -EINVAL;
78 
79 	/* Increase the usage counter */
80 	vma->inuse++;
81 
82 	if (vma->mapped)
83 		return 0;
84 
85 	vma->mapped = true;
86 
87 	if (aspace && aspace->mmu)
88 		ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt,
89 				size, prot);
90 
91 	if (ret) {
92 		vma->mapped = false;
93 		vma->inuse--;
94 	}
95 
96 	return ret;
97 }
98 
99 /* Close an iova.  Warn if it is still in use */
100 void msm_gem_close_vma(struct msm_gem_address_space *aspace,
101 		struct msm_gem_vma *vma)
102 {
103 	if (WARN_ON(vma->inuse > 0 || vma->mapped))
104 		return;
105 
106 	spin_lock(&aspace->lock);
107 	if (vma->iova)
108 		drm_mm_remove_node(&vma->node);
109 	spin_unlock(&aspace->lock);
110 
111 	vma->iova = 0;
112 
113 	msm_gem_address_space_put(aspace);
114 }
115 
116 /* Initialize a new vma and allocate an iova for it */
117 int msm_gem_init_vma(struct msm_gem_address_space *aspace,
118 		struct msm_gem_vma *vma, int npages,
119 		u64 range_start, u64 range_end)
120 {
121 	int ret;
122 
123 	if (WARN_ON(vma->iova))
124 		return -EBUSY;
125 
126 	spin_lock(&aspace->lock);
127 	ret = drm_mm_insert_node_in_range(&aspace->mm, &vma->node, npages, 0,
128 		0, range_start, range_end, 0);
129 	spin_unlock(&aspace->lock);
130 
131 	if (ret)
132 		return ret;
133 
134 	vma->iova = vma->node.start << PAGE_SHIFT;
135 	vma->mapped = false;
136 
137 	kref_get(&aspace->kref);
138 
139 	return 0;
140 }
141 
142 struct msm_gem_address_space *
143 msm_gem_address_space_create(struct msm_mmu *mmu, const char *name,
144 		u64 va_start, u64 size)
145 {
146 	struct msm_gem_address_space *aspace;
147 
148 	if (IS_ERR(mmu))
149 		return ERR_CAST(mmu);
150 
151 	aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
152 	if (!aspace)
153 		return ERR_PTR(-ENOMEM);
154 
155 	spin_lock_init(&aspace->lock);
156 	aspace->name = name;
157 	aspace->mmu = mmu;
158 
159 	drm_mm_init(&aspace->mm, va_start >> PAGE_SHIFT, size >> PAGE_SHIFT);
160 
161 	kref_init(&aspace->kref);
162 
163 	return aspace;
164 }
165