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_fence.h"
9 #include "msm_gem.h"
10 #include "msm_mmu.h"
11 
12 static void
msm_gem_address_space_destroy(struct kref * kref)13 msm_gem_address_space_destroy(struct kref *kref)
14 {
15 	struct msm_gem_address_space *aspace = container_of(kref,
16 			struct msm_gem_address_space, kref);
17 
18 	drm_mm_takedown(&aspace->mm);
19 	if (aspace->mmu)
20 		aspace->mmu->funcs->destroy(aspace->mmu);
21 	put_pid(aspace->pid);
22 	kfree(aspace);
23 }
24 
25 
msm_gem_address_space_put(struct msm_gem_address_space * aspace)26 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
27 {
28 	if (aspace)
29 		kref_put(&aspace->kref, msm_gem_address_space_destroy);
30 }
31 
32 struct msm_gem_address_space *
msm_gem_address_space_get(struct msm_gem_address_space * aspace)33 msm_gem_address_space_get(struct msm_gem_address_space *aspace)
34 {
35 	if (!IS_ERR_OR_NULL(aspace))
36 		kref_get(&aspace->kref);
37 
38 	return aspace;
39 }
40 
msm_gem_vma_inuse(struct msm_gem_vma * vma)41 bool msm_gem_vma_inuse(struct msm_gem_vma *vma)
42 {
43 	if (vma->inuse > 0)
44 		return true;
45 
46 	while (vma->fence_mask) {
47 		unsigned idx = ffs(vma->fence_mask) - 1;
48 
49 		if (!msm_fence_completed(vma->fctx[idx], vma->fence[idx]))
50 			return true;
51 
52 		vma->fence_mask &= ~BIT(idx);
53 	}
54 
55 	return false;
56 }
57 
58 /* Actually unmap memory for the vma */
msm_gem_purge_vma(struct msm_gem_address_space * aspace,struct msm_gem_vma * vma)59 void msm_gem_purge_vma(struct msm_gem_address_space *aspace,
60 		struct msm_gem_vma *vma)
61 {
62 	unsigned size = vma->node.size;
63 
64 	/* Print a message if we try to purge a vma in use */
65 	GEM_WARN_ON(msm_gem_vma_inuse(vma));
66 
67 	/* Don't do anything if the memory isn't mapped */
68 	if (!vma->mapped)
69 		return;
70 
71 	if (aspace->mmu)
72 		aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, size);
73 
74 	vma->mapped = false;
75 }
76 
77 /* Remove reference counts for the mapping */
msm_gem_unpin_vma(struct msm_gem_vma * vma)78 void msm_gem_unpin_vma(struct msm_gem_vma *vma)
79 {
80 	if (GEM_WARN_ON(!vma->inuse))
81 		return;
82 	if (!GEM_WARN_ON(!vma->iova))
83 		vma->inuse--;
84 }
85 
86 /* Replace pin reference with fence: */
msm_gem_unpin_vma_fenced(struct msm_gem_vma * vma,struct msm_fence_context * fctx)87 void msm_gem_unpin_vma_fenced(struct msm_gem_vma *vma, struct msm_fence_context *fctx)
88 {
89 	vma->fctx[fctx->index] = fctx;
90 	vma->fence[fctx->index] = fctx->last_fence;
91 	vma->fence_mask |= BIT(fctx->index);
92 	msm_gem_unpin_vma(vma);
93 }
94 
95 /* Map and pin vma: */
96 int
msm_gem_map_vma(struct msm_gem_address_space * aspace,struct msm_gem_vma * vma,int prot,struct sg_table * sgt,int size)97 msm_gem_map_vma(struct msm_gem_address_space *aspace,
98 		struct msm_gem_vma *vma, int prot,
99 		struct sg_table *sgt, int size)
100 {
101 	int ret = 0;
102 
103 	if (GEM_WARN_ON(!vma->iova))
104 		return -EINVAL;
105 
106 	/* Increase the usage counter */
107 	vma->inuse++;
108 
109 	if (vma->mapped)
110 		return 0;
111 
112 	vma->mapped = true;
113 
114 	if (aspace && aspace->mmu)
115 		ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt,
116 				size, prot);
117 
118 	if (ret) {
119 		vma->mapped = false;
120 		vma->inuse--;
121 	}
122 
123 	return ret;
124 }
125 
126 /* Close an iova.  Warn if it is still in use */
msm_gem_close_vma(struct msm_gem_address_space * aspace,struct msm_gem_vma * vma)127 void msm_gem_close_vma(struct msm_gem_address_space *aspace,
128 		struct msm_gem_vma *vma)
129 {
130 	GEM_WARN_ON(msm_gem_vma_inuse(vma) || vma->mapped);
131 
132 	spin_lock(&aspace->lock);
133 	if (vma->iova)
134 		drm_mm_remove_node(&vma->node);
135 	spin_unlock(&aspace->lock);
136 
137 	vma->iova = 0;
138 
139 	msm_gem_address_space_put(aspace);
140 }
141 
142 /* Initialize a new vma and allocate an iova for it */
msm_gem_init_vma(struct msm_gem_address_space * aspace,struct msm_gem_vma * vma,int size,u64 range_start,u64 range_end)143 int msm_gem_init_vma(struct msm_gem_address_space *aspace,
144 		struct msm_gem_vma *vma, int size,
145 		u64 range_start, u64 range_end)
146 {
147 	int ret;
148 
149 	if (GEM_WARN_ON(vma->iova))
150 		return -EBUSY;
151 
152 	spin_lock(&aspace->lock);
153 	ret = drm_mm_insert_node_in_range(&aspace->mm, &vma->node,
154 					  size, PAGE_SIZE, 0,
155 					  range_start, range_end, 0);
156 	spin_unlock(&aspace->lock);
157 
158 	if (ret)
159 		return ret;
160 
161 	vma->iova = vma->node.start;
162 	vma->mapped = false;
163 
164 	kref_get(&aspace->kref);
165 
166 	return 0;
167 }
168 
169 struct msm_gem_address_space *
msm_gem_address_space_create(struct msm_mmu * mmu,const char * name,u64 va_start,u64 size)170 msm_gem_address_space_create(struct msm_mmu *mmu, const char *name,
171 		u64 va_start, u64 size)
172 {
173 	struct msm_gem_address_space *aspace;
174 
175 	if (IS_ERR(mmu))
176 		return ERR_CAST(mmu);
177 
178 	aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
179 	if (!aspace)
180 		return ERR_PTR(-ENOMEM);
181 
182 	spin_lock_init(&aspace->lock);
183 	aspace->name = name;
184 	aspace->mmu = mmu;
185 	aspace->va_start = va_start;
186 	aspace->va_size  = size;
187 
188 	drm_mm_init(&aspace->mm, va_start, size);
189 
190 	kref_init(&aspace->kref);
191 
192 	return aspace;
193 }
194