v3d_bo.c

  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
 18#include <linux/dma-buf.h>
 19#include <linux/vmalloc.h>
 20
 21#include <drm/drm_print.h>
 22
 23#include "v3d_drv.h"
 24#include "uapi/drm/v3d_drm.h"
 25
 26static enum drm_gem_object_status v3d_gem_status(struct drm_gem_object *obj)
 27{
 28	struct v3d_bo *bo = to_v3d_bo(obj);
 29	enum drm_gem_object_status res = 0;
 30
 31	if (bo->base.pages)
 32		res |= DRM_GEM_OBJECT_RESIDENT;
 33
 34	return res;
 35}
 36
 37/* Called DRM core on the last userspace/kernel unreference of the
 38 * BO.
 39 */
 40void v3d_free_object(struct drm_gem_object *obj)
 41{
 42	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
 43	struct v3d_bo *bo = to_v3d_bo(obj);
 44
 45	if (bo->vaddr)
 46		v3d_put_bo_vaddr(bo);
 47
 48	v3d_mmu_remove_ptes(bo);
 49
 50	mutex_lock(&v3d->bo_lock);
 51	v3d->bo_stats.num_allocated--;
 52	v3d->bo_stats.pages_allocated -= obj->size >> V3D_MMU_PAGE_SHIFT;
 53	mutex_unlock(&v3d->bo_lock);
 54
 55	spin_lock(&v3d->mm_lock);
 56	drm_mm_remove_node(&bo->node);
 57	spin_unlock(&v3d->mm_lock);
 58
 59	/* GPU execution may have dirtied any pages in the BO. */
 60	bo->base.pages_mark_dirty_on_put = true;
 61
 62	drm_gem_shmem_free(&bo->base);
 63}
 64
 65static const struct drm_gem_object_funcs v3d_gem_funcs = {
 66	.free = v3d_free_object,
 67	.print_info = drm_gem_shmem_object_print_info,
 68	.pin = drm_gem_shmem_object_pin,
 69	.unpin = drm_gem_shmem_object_unpin,
 70	.get_sg_table = drm_gem_shmem_object_get_sg_table,
 71	.vmap = drm_gem_shmem_object_vmap,
 72	.vunmap = drm_gem_shmem_object_vunmap,
 73	.mmap = drm_gem_shmem_object_mmap,
 74	.status = v3d_gem_status,
 75	.vm_ops = &drm_gem_shmem_vm_ops,
 76};
 77
 78/* gem_create_object function for allocating a BO struct and doing
 79 * early setup.
 80 */
 81struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
 82{
 83	struct v3d_bo *bo;
 84	struct drm_gem_object *obj;
 85
 86	if (size == 0)
 87		return ERR_PTR(-EINVAL);
 88
 89	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
 90	if (!bo)
 91		return ERR_PTR(-ENOMEM);
 92	obj = &bo->base.base;
 93
 94	obj->funcs = &v3d_gem_funcs;
 95	bo->base.map_wc = true;
 96	INIT_LIST_HEAD(&bo->unref_head);
 97
 98	return &bo->base.base;
 99}
100
101static int
102v3d_bo_create_finish(struct drm_gem_object *obj)
103{
104	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
105	struct v3d_bo *bo = to_v3d_bo(obj);
106	struct sg_table *sgt;
107	u64 align;
108	int ret;
109
110	/* So far we pin the BO in the MMU for its lifetime, so use
111	 * shmem's helper for getting a lifetime sgt.
112	 */
113	sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
114	if (IS_ERR(sgt))
115		return PTR_ERR(sgt);
116
117	if (!v3d->gemfs)
118		align = SZ_4K;
119	else if (obj->size >= SZ_1M)
120		align = SZ_1M;
121	else if (obj->size >= SZ_64K)
122		align = SZ_64K;
123	else
124		align = SZ_4K;
125
126	spin_lock(&v3d->mm_lock);
127	/* Allocate the object's space in the GPU's page tables.
128	 * Inserting PTEs will happen later, but the offset is for the
129	 * lifetime of the BO.
130	 */
131	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
132					 obj->size >> V3D_MMU_PAGE_SHIFT,
133					 align >> V3D_MMU_PAGE_SHIFT, 0, 0);
134	spin_unlock(&v3d->mm_lock);
135	if (ret)
136		return ret;
137
138	/* Track stats for /debug/dri/n/bo_stats. */
139	mutex_lock(&v3d->bo_lock);
140	v3d->bo_stats.num_allocated++;
141	v3d->bo_stats.pages_allocated += obj->size >> V3D_MMU_PAGE_SHIFT;
142	mutex_unlock(&v3d->bo_lock);
143
144	v3d_mmu_insert_ptes(bo);
145
146	return 0;
147}
148
149struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
150			     size_t unaligned_size)
151{
152	struct drm_gem_shmem_object *shmem_obj;
153	struct v3d_dev *v3d = to_v3d_dev(dev);
154	struct v3d_bo *bo;
155	int ret;
156
157	shmem_obj = drm_gem_shmem_create_with_mnt(dev, unaligned_size,
158						  v3d->gemfs);
159	if (IS_ERR(shmem_obj))
160		return ERR_CAST(shmem_obj);
161	bo = to_v3d_bo(&shmem_obj->base);
162	bo->vaddr = NULL;
163
164	ret = v3d_bo_create_finish(&shmem_obj->base);
165	if (ret)
166		goto free_obj;
167
168	return bo;
169
170free_obj:
171	drm_gem_shmem_free(shmem_obj);
172	return ERR_PTR(ret);
173}
174
175struct drm_gem_object *
176v3d_prime_import_sg_table(struct drm_device *dev,
177			  struct dma_buf_attachment *attach,
178			  struct sg_table *sgt)
179{
180	struct drm_gem_object *obj;
181	int ret;
182
183	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
184	if (IS_ERR(obj))
185		return obj;
186
187	ret = v3d_bo_create_finish(obj);
188	if (ret) {
189		drm_gem_shmem_free(&to_v3d_bo(obj)->base);
190		return ERR_PTR(ret);
191	}
192
193	return obj;
194}
195
196void v3d_get_bo_vaddr(struct v3d_bo *bo)
197{
198	struct drm_gem_shmem_object *obj = &bo->base;
199
200	bo->vaddr = vmap(obj->pages, obj->base.size >> PAGE_SHIFT, VM_MAP,
201			 pgprot_writecombine(PAGE_KERNEL));
202}
203
204void v3d_put_bo_vaddr(struct v3d_bo *bo)
205{
206	vunmap(bo->vaddr);
207	bo->vaddr = NULL;
208}
209
210int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
211			struct drm_file *file_priv)
212{
213	struct drm_v3d_create_bo *args = data;
214	struct v3d_bo *bo = NULL;
215	int ret;
216
217	if (args->flags != 0) {
218		DRM_INFO("unknown create_bo flags: %d\n", args->flags);
219		return -EINVAL;
220	}
221
222	bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
223	if (IS_ERR(bo))
224		return PTR_ERR(bo);
225
226	args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
227
228	ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
229	drm_gem_object_put(&bo->base.base);
230
231	return ret;
232}
233
234int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
235		      struct drm_file *file_priv)
236{
237	struct drm_v3d_mmap_bo *args = data;
238	struct drm_gem_object *gem_obj;
239
240	if (args->flags != 0) {
241		DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
242		return -EINVAL;
243	}
244
245	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
246	if (!gem_obj) {
247		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
248		return -ENOENT;
249	}
250
251	args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
252	drm_gem_object_put(gem_obj);
253
254	return 0;
255}
256
257int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
258			    struct drm_file *file_priv)
259{
260	struct drm_v3d_get_bo_offset *args = data;
261	struct drm_gem_object *gem_obj;
262	struct v3d_bo *bo;
263
264	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
265	if (!gem_obj) {
266		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
267		return -ENOENT;
268	}
269	bo = to_v3d_bo(gem_obj);
270
271	args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
272
273	drm_gem_object_put(gem_obj);
274	return 0;
275}
276
277int
278v3d_wait_bo_ioctl(struct drm_device *dev, void *data,
279		  struct drm_file *file_priv)
280{
281	int ret;
282	struct drm_v3d_wait_bo *args = data;
283	ktime_t start = ktime_get();
284	u64 delta_ns;
285	unsigned long timeout_jiffies =
286		nsecs_to_jiffies_timeout(args->timeout_ns);
287
288	if (args->pad != 0)
289		return -EINVAL;
290
291	ret = drm_gem_dma_resv_wait(file_priv, args->handle,
292				    true, timeout_jiffies);
293
294	/* Decrement the user's timeout, in case we got interrupted
295	 * such that the ioctl will be restarted.
296	 */
297	delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start));
298	if (delta_ns < args->timeout_ns)
299		args->timeout_ns -= delta_ns;
300	else
301		args->timeout_ns = 0;
302
303	/* Asked to wait beyond the jiffy/scheduler precision? */
304	if (ret == -ETIME && args->timeout_ns)
305		ret = -EAGAIN;
306
307	return ret;
308}