xref: /openbmc/linux/drivers/gpu/drm/msm/msm_gem_vma.c (revision f97769fd)
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 	kfree(aspace);
21 }
22 
23 
24 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
25 {
26 	if (aspace)
27 		kref_put(&aspace->kref, msm_gem_address_space_destroy);
28 }
29 
30 /* Actually unmap memory for the vma */
31 void msm_gem_purge_vma(struct msm_gem_address_space *aspace,
32 		struct msm_gem_vma *vma)
33 {
34 	unsigned size = vma->node.size << PAGE_SHIFT;
35 
36 	/* Print a message if we try to purge a vma in use */
37 	if (WARN_ON(vma->inuse > 0))
38 		return;
39 
40 	/* Don't do anything if the memory isn't mapped */
41 	if (!vma->mapped)
42 		return;
43 
44 	if (aspace->mmu)
45 		aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, size);
46 
47 	vma->mapped = false;
48 }
49 
50 /* Remove reference counts for the mapping */
51 void msm_gem_unmap_vma(struct msm_gem_address_space *aspace,
52 		struct msm_gem_vma *vma)
53 {
54 	if (!WARN_ON(!vma->iova))
55 		vma->inuse--;
56 }
57 
58 int
59 msm_gem_map_vma(struct msm_gem_address_space *aspace,
60 		struct msm_gem_vma *vma, int prot,
61 		struct sg_table *sgt, int npages)
62 {
63 	unsigned size = npages << PAGE_SHIFT;
64 	int ret = 0;
65 
66 	if (WARN_ON(!vma->iova))
67 		return -EINVAL;
68 
69 	/* Increase the usage counter */
70 	vma->inuse++;
71 
72 	if (vma->mapped)
73 		return 0;
74 
75 	vma->mapped = true;
76 
77 	if (aspace && aspace->mmu)
78 		ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt,
79 				size, prot);
80 
81 	if (ret)
82 		vma->mapped = false;
83 
84 	return ret;
85 }
86 
87 /* Close an iova.  Warn if it is still in use */
88 void msm_gem_close_vma(struct msm_gem_address_space *aspace,
89 		struct msm_gem_vma *vma)
90 {
91 	if (WARN_ON(vma->inuse > 0 || vma->mapped))
92 		return;
93 
94 	spin_lock(&aspace->lock);
95 	if (vma->iova)
96 		drm_mm_remove_node(&vma->node);
97 	spin_unlock(&aspace->lock);
98 
99 	vma->iova = 0;
100 
101 	msm_gem_address_space_put(aspace);
102 }
103 
104 /* Initialize a new vma and allocate an iova for it */
105 int msm_gem_init_vma(struct msm_gem_address_space *aspace,
106 		struct msm_gem_vma *vma, int npages,
107 		u64 range_start, u64 range_end)
108 {
109 	int ret;
110 
111 	if (WARN_ON(vma->iova))
112 		return -EBUSY;
113 
114 	spin_lock(&aspace->lock);
115 	ret = drm_mm_insert_node_in_range(&aspace->mm, &vma->node, npages, 0,
116 		0, range_start, range_end, 0);
117 	spin_unlock(&aspace->lock);
118 
119 	if (ret)
120 		return ret;
121 
122 	vma->iova = vma->node.start << PAGE_SHIFT;
123 	vma->mapped = false;
124 
125 	kref_get(&aspace->kref);
126 
127 	return 0;
128 }
129 
130 struct msm_gem_address_space *
131 msm_gem_address_space_create(struct msm_mmu *mmu, const char *name,
132 		u64 va_start, u64 size)
133 {
134 	struct msm_gem_address_space *aspace;
135 
136 	if (IS_ERR(mmu))
137 		return ERR_CAST(mmu);
138 
139 	aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
140 	if (!aspace)
141 		return ERR_PTR(-ENOMEM);
142 
143 	spin_lock_init(&aspace->lock);
144 	aspace->name = name;
145 	aspace->mmu = mmu;
146 
147 	drm_mm_init(&aspace->mm, va_start >> PAGE_SHIFT, size >> PAGE_SHIFT);
148 
149 	kref_init(&aspace->kref);
150 
151 	return aspace;
152 }
153