1// SPDX-License-Identifier: GPL-2.0+
2/* Copyright (C) 2015-2018 Broadcom */
3
4/**
5 * DOC: V3D GEM BO management support
6 *
7 * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
8 * GPU and the bus, allowing us to use shmem objects for our storage
9 * instead of CMA.
10 *
11 * Physically contiguous objects may still be imported to V3D, but the
12 * driver doesn't allocate physically contiguous objects on its own.
13 * Display engines requiring physically contiguous allocations should
14 * look into Mesa's "renderonly" support (as used by the Mesa pl111
15 * driver) for an example of how to integrate with V3D.
16 *
17 * Long term, we should support evicting pages from the MMU when under
18 * memory pressure (thus the v3d_bo_get_pages() refcounting), but
19 * that's not a high priority since our systems tend to not have swap.
20 */
21
22#include <linux/dma-buf.h>
23#include <linux/pfn_t.h>
24
25#include "v3d_drv.h"
26#include "uapi/drm/v3d_drm.h"
27
28/* Called DRM core on the last userspace/kernel unreference of the
29 * BO.
30 */
31void v3d_free_object(struct drm_gem_object *obj)
32{
33 struct v3d_dev *v3d = to_v3d_dev(dev: obj->dev);
34 struct v3d_bo *bo = to_v3d_bo(bo: obj);
35
36 v3d_mmu_remove_ptes(bo);
37
38 mutex_lock(&v3d->bo_lock);
39 v3d->bo_stats.num_allocated--;
40 v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
41 mutex_unlock(lock: &v3d->bo_lock);
42
43 spin_lock(lock: &v3d->mm_lock);
44 drm_mm_remove_node(node: &bo->node);
45 spin_unlock(lock: &v3d->mm_lock);
46
47 /* GPU execution may have dirtied any pages in the BO. */
48 bo->base.pages_mark_dirty_on_put = true;
49
50 drm_gem_shmem_free(shmem: &bo->base);
51}
52
53static const struct drm_gem_object_funcs v3d_gem_funcs = {
54 .free = v3d_free_object,
55 .print_info = drm_gem_shmem_object_print_info,
56 .pin = drm_gem_shmem_object_pin,
57 .unpin = drm_gem_shmem_object_unpin,
58 .get_sg_table = drm_gem_shmem_object_get_sg_table,
59 .vmap = drm_gem_shmem_object_vmap,
60 .vunmap = drm_gem_shmem_object_vunmap,
61 .mmap = drm_gem_shmem_object_mmap,
62 .vm_ops = &drm_gem_shmem_vm_ops,
63};
64
65/* gem_create_object function for allocating a BO struct and doing
66 * early setup.
67 */
68struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
69{
70 struct v3d_bo *bo;
71 struct drm_gem_object *obj;
72
73 if (size == 0)
74 return ERR_PTR(error: -EINVAL);
75
76 bo = kzalloc(size: sizeof(*bo), GFP_KERNEL);
77 if (!bo)
78 return ERR_PTR(error: -ENOMEM);
79 obj = &bo->base.base;
80
81 obj->funcs = &v3d_gem_funcs;
82 bo->base.map_wc = true;
83 INIT_LIST_HEAD(list: &bo->unref_head);
84
85 return &bo->base.base;
86}
87
88static int
89v3d_bo_create_finish(struct drm_gem_object *obj)
90{
91 struct v3d_dev *v3d = to_v3d_dev(dev: obj->dev);
92 struct v3d_bo *bo = to_v3d_bo(bo: obj);
93 struct sg_table *sgt;
94 int ret;
95
96 /* So far we pin the BO in the MMU for its lifetime, so use
97 * shmem's helper for getting a lifetime sgt.
98 */
99 sgt = drm_gem_shmem_get_pages_sgt(shmem: &bo->base);
100 if (IS_ERR(ptr: sgt))
101 return PTR_ERR(ptr: sgt);
102
103 spin_lock(lock: &v3d->mm_lock);
104 /* Allocate the object's space in the GPU's page tables.
105 * Inserting PTEs will happen later, but the offset is for the
106 * lifetime of the BO.
107 */
108 ret = drm_mm_insert_node_generic(mm: &v3d->mm, node: &bo->node,
109 size: obj->size >> PAGE_SHIFT,
110 GMP_GRANULARITY >> PAGE_SHIFT, color: 0, mode: 0);
111 spin_unlock(lock: &v3d->mm_lock);
112 if (ret)
113 return ret;
114
115 /* Track stats for /debug/dri/n/bo_stats. */
116 mutex_lock(&v3d->bo_lock);
117 v3d->bo_stats.num_allocated++;
118 v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
119 mutex_unlock(lock: &v3d->bo_lock);
120
121 v3d_mmu_insert_ptes(bo);
122
123 return 0;
124}
125
126struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
127 size_t unaligned_size)
128{
129 struct drm_gem_shmem_object *shmem_obj;
130 struct v3d_bo *bo;
131 int ret;
132
133 shmem_obj = drm_gem_shmem_create(dev, size: unaligned_size);
134 if (IS_ERR(ptr: shmem_obj))
135 return ERR_CAST(ptr: shmem_obj);
136 bo = to_v3d_bo(bo: &shmem_obj->base);
137
138 ret = v3d_bo_create_finish(obj: &shmem_obj->base);
139 if (ret)
140 goto free_obj;
141
142 return bo;
143
144free_obj:
145 drm_gem_shmem_free(shmem: shmem_obj);
146 return ERR_PTR(error: ret);
147}
148
149struct drm_gem_object *
150v3d_prime_import_sg_table(struct drm_device *dev,
151 struct dma_buf_attachment *attach,
152 struct sg_table *sgt)
153{
154 struct drm_gem_object *obj;
155 int ret;
156
157 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
158 if (IS_ERR(ptr: obj))
159 return obj;
160
161 ret = v3d_bo_create_finish(obj);
162 if (ret) {
163 drm_gem_shmem_free(shmem: &to_v3d_bo(bo: obj)->base);
164 return ERR_PTR(error: ret);
165 }
166
167 return obj;
168}
169
170int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
171 struct drm_file *file_priv)
172{
173 struct drm_v3d_create_bo *args = data;
174 struct v3d_bo *bo = NULL;
175 int ret;
176
177 if (args->flags != 0) {
178 DRM_INFO("unknown create_bo flags: %d\n", args->flags);
179 return -EINVAL;
180 }
181
182 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
183 if (IS_ERR(ptr: bo))
184 return PTR_ERR(ptr: bo);
185
186 args->offset = bo->node.start << PAGE_SHIFT;
187
188 ret = drm_gem_handle_create(file_priv, obj: &bo->base.base, handlep: &args->handle);
189 drm_gem_object_put(obj: &bo->base.base);
190
191 return ret;
192}
193
194int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
195 struct drm_file *file_priv)
196{
197 struct drm_v3d_mmap_bo *args = data;
198 struct drm_gem_object *gem_obj;
199
200 if (args->flags != 0) {
201 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
202 return -EINVAL;
203 }
204
205 gem_obj = drm_gem_object_lookup(filp: file_priv, handle: args->handle);
206 if (!gem_obj) {
207 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
208 return -ENOENT;
209 }
210
211 args->offset = drm_vma_node_offset_addr(node: &gem_obj->vma_node);
212 drm_gem_object_put(obj: gem_obj);
213
214 return 0;
215}
216
217int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
218 struct drm_file *file_priv)
219{
220 struct drm_v3d_get_bo_offset *args = data;
221 struct drm_gem_object *gem_obj;
222 struct v3d_bo *bo;
223
224 gem_obj = drm_gem_object_lookup(filp: file_priv, handle: args->handle);
225 if (!gem_obj) {
226 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
227 return -ENOENT;
228 }
229 bo = to_v3d_bo(bo: gem_obj);
230
231 args->offset = bo->node.start << PAGE_SHIFT;
232
233 drm_gem_object_put(obj: gem_obj);
234 return 0;
235}
236

source code of linux/drivers/gpu/drm/v3d/v3d_bo.c