1 /*
2 * videobuf2-dma-sg.c - dma scatter/gather memory allocator for videobuf2
3 *
4 * Copyright (C) 2010 Samsung Electronics
5 *
6 * Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation.
11 */
12
13 #include <linux/module.h>
14 #include <linux/mm.h>
15 #include <linux/refcount.h>
16 #include <linux/scatterlist.h>
17 #include <linux/sched.h>
18 #include <linux/slab.h>
19 #include <linux/vmalloc.h>
20
21 #include <media/videobuf2-v4l2.h>
22 #include <media/videobuf2-memops.h>
23 #include <media/videobuf2-dma-sg.h>
24
25 static int debug;
26 module_param(debug, int, 0644);
27
28 #define dprintk(level, fmt, arg...) \
29 do { \
30 if (debug >= level) \
31 printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg); \
32 } while (0)
33
34 struct vb2_dma_sg_buf {
35 struct device *dev;
36 void *vaddr;
37 struct page **pages;
38 struct frame_vector *vec;
39 int offset;
40 enum dma_data_direction dma_dir;
41 struct sg_table sg_table;
42 /*
43 * This will point to sg_table when used with the MMAP or USERPTR
44 * memory model, and to the dma_buf sglist when used with the
45 * DMABUF memory model.
46 */
47 struct sg_table *dma_sgt;
48 size_t size;
49 unsigned int num_pages;
50 refcount_t refcount;
51 struct vb2_vmarea_handler handler;
52
53 struct dma_buf_attachment *db_attach;
54
55 struct vb2_buffer *vb;
56 };
57
58 static void vb2_dma_sg_put(void *buf_priv);
59
vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf * buf,gfp_t gfp_flags)60 static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf,
61 gfp_t gfp_flags)
62 {
63 unsigned int last_page = 0;
64 unsigned long size = buf->size;
65
66 while (size > 0) {
67 struct page *pages;
68 int order;
69 int i;
70
71 order = get_order(size);
72 /* Don't over allocate*/
73 if ((PAGE_SIZE << order) > size)
74 order--;
75
76 pages = NULL;
77 while (!pages) {
78 pages = alloc_pages(GFP_KERNEL | __GFP_ZERO |
79 __GFP_NOWARN | gfp_flags, order);
80 if (pages)
81 break;
82
83 if (order == 0) {
84 while (last_page--)
85 __free_page(buf->pages[last_page]);
86 return -ENOMEM;
87 }
88 order--;
89 }
90
91 split_page(pages, order);
92 for (i = 0; i < (1 << order); i++)
93 buf->pages[last_page++] = &pages[i];
94
95 size -= PAGE_SIZE << order;
96 }
97
98 return 0;
99 }
100
vb2_dma_sg_alloc(struct vb2_buffer * vb,struct device * dev,unsigned long size)101 static void *vb2_dma_sg_alloc(struct vb2_buffer *vb, struct device *dev,
102 unsigned long size)
103 {
104 struct vb2_dma_sg_buf *buf;
105 struct sg_table *sgt;
106 int ret;
107 int num_pages;
108
109 if (WARN_ON(!dev) || WARN_ON(!size))
110 return ERR_PTR(-EINVAL);
111
112 buf = kzalloc(sizeof *buf, GFP_KERNEL);
113 if (!buf)
114 return ERR_PTR(-ENOMEM);
115
116 buf->vaddr = NULL;
117 buf->dma_dir = vb->vb2_queue->dma_dir;
118 buf->offset = 0;
119 buf->size = size;
120 /* size is already page aligned */
121 buf->num_pages = size >> PAGE_SHIFT;
122 buf->dma_sgt = &buf->sg_table;
123
124 /*
125 * NOTE: dma-sg allocates memory using the page allocator directly, so
126 * there is no memory consistency guarantee, hence dma-sg ignores DMA
127 * attributes passed from the upper layer.
128 */
129 buf->pages = kvcalloc(buf->num_pages, sizeof(struct page *), GFP_KERNEL);
130 if (!buf->pages)
131 goto fail_pages_array_alloc;
132
133 ret = vb2_dma_sg_alloc_compacted(buf, vb->vb2_queue->gfp_flags);
134 if (ret)
135 goto fail_pages_alloc;
136
137 ret = sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
138 buf->num_pages, 0, size, GFP_KERNEL);
139 if (ret)
140 goto fail_table_alloc;
141
142 /* Prevent the device from being released while the buffer is used */
143 buf->dev = get_device(dev);
144
145 sgt = &buf->sg_table;
146 /*
147 * No need to sync to the device, this will happen later when the
148 * prepare() memop is called.
149 */
150 if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
151 DMA_ATTR_SKIP_CPU_SYNC))
152 goto fail_map;
153
154 buf->handler.refcount = &buf->refcount;
155 buf->handler.put = vb2_dma_sg_put;
156 buf->handler.arg = buf;
157 buf->vb = vb;
158
159 refcount_set(&buf->refcount, 1);
160
161 dprintk(1, "%s: Allocated buffer of %d pages\n",
162 __func__, buf->num_pages);
163 return buf;
164
165 fail_map:
166 put_device(buf->dev);
167 sg_free_table(buf->dma_sgt);
168 fail_table_alloc:
169 num_pages = buf->num_pages;
170 while (num_pages--)
171 __free_page(buf->pages[num_pages]);
172 fail_pages_alloc:
173 kvfree(buf->pages);
174 fail_pages_array_alloc:
175 kfree(buf);
176 return ERR_PTR(-ENOMEM);
177 }
178
vb2_dma_sg_put(void * buf_priv)179 static void vb2_dma_sg_put(void *buf_priv)
180 {
181 struct vb2_dma_sg_buf *buf = buf_priv;
182 struct sg_table *sgt = &buf->sg_table;
183 int i = buf->num_pages;
184
185 if (refcount_dec_and_test(&buf->refcount)) {
186 dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
187 buf->num_pages);
188 dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir,
189 DMA_ATTR_SKIP_CPU_SYNC);
190 if (buf->vaddr)
191 vm_unmap_ram(buf->vaddr, buf->num_pages);
192 sg_free_table(buf->dma_sgt);
193 while (--i >= 0)
194 __free_page(buf->pages[i]);
195 kvfree(buf->pages);
196 put_device(buf->dev);
197 kfree(buf);
198 }
199 }
200
vb2_dma_sg_prepare(void * buf_priv)201 static void vb2_dma_sg_prepare(void *buf_priv)
202 {
203 struct vb2_dma_sg_buf *buf = buf_priv;
204 struct sg_table *sgt = buf->dma_sgt;
205
206 if (buf->vb->skip_cache_sync_on_prepare)
207 return;
208
209 dma_sync_sgtable_for_device(buf->dev, sgt, buf->dma_dir);
210 }
211
vb2_dma_sg_finish(void * buf_priv)212 static void vb2_dma_sg_finish(void *buf_priv)
213 {
214 struct vb2_dma_sg_buf *buf = buf_priv;
215 struct sg_table *sgt = buf->dma_sgt;
216
217 if (buf->vb->skip_cache_sync_on_finish)
218 return;
219
220 dma_sync_sgtable_for_cpu(buf->dev, sgt, buf->dma_dir);
221 }
222
vb2_dma_sg_get_userptr(struct vb2_buffer * vb,struct device * dev,unsigned long vaddr,unsigned long size)223 static void *vb2_dma_sg_get_userptr(struct vb2_buffer *vb, struct device *dev,
224 unsigned long vaddr, unsigned long size)
225 {
226 struct vb2_dma_sg_buf *buf;
227 struct sg_table *sgt;
228 struct frame_vector *vec;
229
230 if (WARN_ON(!dev))
231 return ERR_PTR(-EINVAL);
232
233 buf = kzalloc(sizeof *buf, GFP_KERNEL);
234 if (!buf)
235 return ERR_PTR(-ENOMEM);
236
237 buf->vaddr = NULL;
238 buf->dev = dev;
239 buf->dma_dir = vb->vb2_queue->dma_dir;
240 buf->offset = vaddr & ~PAGE_MASK;
241 buf->size = size;
242 buf->dma_sgt = &buf->sg_table;
243 buf->vb = vb;
244 vec = vb2_create_framevec(vaddr, size);
245 if (IS_ERR(vec))
246 goto userptr_fail_pfnvec;
247 buf->vec = vec;
248
249 buf->pages = frame_vector_pages(vec);
250 if (IS_ERR(buf->pages))
251 goto userptr_fail_sgtable;
252 buf->num_pages = frame_vector_count(vec);
253
254 if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
255 buf->num_pages, buf->offset, size, 0))
256 goto userptr_fail_sgtable;
257
258 sgt = &buf->sg_table;
259 /*
260 * No need to sync to the device, this will happen later when the
261 * prepare() memop is called.
262 */
263 if (dma_map_sgtable(buf->dev, sgt, buf->dma_dir,
264 DMA_ATTR_SKIP_CPU_SYNC))
265 goto userptr_fail_map;
266
267 return buf;
268
269 userptr_fail_map:
270 sg_free_table(&buf->sg_table);
271 userptr_fail_sgtable:
272 vb2_destroy_framevec(vec);
273 userptr_fail_pfnvec:
274 kfree(buf);
275 return ERR_PTR(-ENOMEM);
276 }
277
278 /*
279 * @put_userptr: inform the allocator that a USERPTR buffer will no longer
280 * be used
281 */
vb2_dma_sg_put_userptr(void * buf_priv)282 static void vb2_dma_sg_put_userptr(void *buf_priv)
283 {
284 struct vb2_dma_sg_buf *buf = buf_priv;
285 struct sg_table *sgt = &buf->sg_table;
286 int i = buf->num_pages;
287
288 dprintk(1, "%s: Releasing userspace buffer of %d pages\n",
289 __func__, buf->num_pages);
290 dma_unmap_sgtable(buf->dev, sgt, buf->dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
291 if (buf->vaddr)
292 vm_unmap_ram(buf->vaddr, buf->num_pages);
293 sg_free_table(buf->dma_sgt);
294 if (buf->dma_dir == DMA_FROM_DEVICE ||
295 buf->dma_dir == DMA_BIDIRECTIONAL)
296 while (--i >= 0)
297 set_page_dirty_lock(buf->pages[i]);
298 vb2_destroy_framevec(buf->vec);
299 kfree(buf);
300 }
301
vb2_dma_sg_vaddr(struct vb2_buffer * vb,void * buf_priv)302 static void *vb2_dma_sg_vaddr(struct vb2_buffer *vb, void *buf_priv)
303 {
304 struct vb2_dma_sg_buf *buf = buf_priv;
305 struct iosys_map map;
306 int ret;
307
308 BUG_ON(!buf);
309
310 if (!buf->vaddr) {
311 if (buf->db_attach) {
312 ret = dma_buf_vmap(buf->db_attach->dmabuf, &map);
313 buf->vaddr = ret ? NULL : map.vaddr;
314 } else {
315 buf->vaddr = vm_map_ram(buf->pages, buf->num_pages, -1);
316 }
317 }
318
319 /* add offset in case userptr is not page-aligned */
320 return buf->vaddr ? buf->vaddr + buf->offset : NULL;
321 }
322
vb2_dma_sg_num_users(void * buf_priv)323 static unsigned int vb2_dma_sg_num_users(void *buf_priv)
324 {
325 struct vb2_dma_sg_buf *buf = buf_priv;
326
327 return refcount_read(&buf->refcount);
328 }
329
vb2_dma_sg_mmap(void * buf_priv,struct vm_area_struct * vma)330 static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma)
331 {
332 struct vb2_dma_sg_buf *buf = buf_priv;
333 int err;
334
335 if (!buf) {
336 printk(KERN_ERR "No memory to map\n");
337 return -EINVAL;
338 }
339
340 err = vm_map_pages(vma, buf->pages, buf->num_pages);
341 if (err) {
342 printk(KERN_ERR "Remapping memory, error: %d\n", err);
343 return err;
344 }
345
346 /*
347 * Use common vm_area operations to track buffer refcount.
348 */
349 vma->vm_private_data = &buf->handler;
350 vma->vm_ops = &vb2_common_vm_ops;
351
352 vma->vm_ops->open(vma);
353
354 return 0;
355 }
356
357 /*********************************************/
358 /* DMABUF ops for exporters */
359 /*********************************************/
360
361 struct vb2_dma_sg_attachment {
362 struct sg_table sgt;
363 enum dma_data_direction dma_dir;
364 };
365
vb2_dma_sg_dmabuf_ops_attach(struct dma_buf * dbuf,struct dma_buf_attachment * dbuf_attach)366 static int vb2_dma_sg_dmabuf_ops_attach(struct dma_buf *dbuf,
367 struct dma_buf_attachment *dbuf_attach)
368 {
369 struct vb2_dma_sg_attachment *attach;
370 unsigned int i;
371 struct scatterlist *rd, *wr;
372 struct sg_table *sgt;
373 struct vb2_dma_sg_buf *buf = dbuf->priv;
374 int ret;
375
376 attach = kzalloc(sizeof(*attach), GFP_KERNEL);
377 if (!attach)
378 return -ENOMEM;
379
380 sgt = &attach->sgt;
381 /* Copy the buf->base_sgt scatter list to the attachment, as we can't
382 * map the same scatter list to multiple attachments at the same time.
383 */
384 ret = sg_alloc_table(sgt, buf->dma_sgt->orig_nents, GFP_KERNEL);
385 if (ret) {
386 kfree(attach);
387 return -ENOMEM;
388 }
389
390 rd = buf->dma_sgt->sgl;
391 wr = sgt->sgl;
392 for (i = 0; i < sgt->orig_nents; ++i) {
393 sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
394 rd = sg_next(rd);
395 wr = sg_next(wr);
396 }
397
398 attach->dma_dir = DMA_NONE;
399 dbuf_attach->priv = attach;
400
401 return 0;
402 }
403
vb2_dma_sg_dmabuf_ops_detach(struct dma_buf * dbuf,struct dma_buf_attachment * db_attach)404 static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf,
405 struct dma_buf_attachment *db_attach)
406 {
407 struct vb2_dma_sg_attachment *attach = db_attach->priv;
408 struct sg_table *sgt;
409
410 if (!attach)
411 return;
412
413 sgt = &attach->sgt;
414
415 /* release the scatterlist cache */
416 if (attach->dma_dir != DMA_NONE)
417 dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir, 0);
418 sg_free_table(sgt);
419 kfree(attach);
420 db_attach->priv = NULL;
421 }
422
vb2_dma_sg_dmabuf_ops_map(struct dma_buf_attachment * db_attach,enum dma_data_direction dma_dir)423 static struct sg_table *vb2_dma_sg_dmabuf_ops_map(
424 struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
425 {
426 struct vb2_dma_sg_attachment *attach = db_attach->priv;
427 /* stealing dmabuf mutex to serialize map/unmap operations */
428 struct mutex *lock = &db_attach->dmabuf->lock;
429 struct sg_table *sgt;
430
431 mutex_lock(lock);
432
433 sgt = &attach->sgt;
434 /* return previously mapped sg table */
435 if (attach->dma_dir == dma_dir) {
436 mutex_unlock(lock);
437 return sgt;
438 }
439
440 /* release any previous cache */
441 if (attach->dma_dir != DMA_NONE) {
442 dma_unmap_sgtable(db_attach->dev, sgt, attach->dma_dir, 0);
443 attach->dma_dir = DMA_NONE;
444 }
445
446 /* mapping to the client with new direction */
447 if (dma_map_sgtable(db_attach->dev, sgt, dma_dir, 0)) {
448 pr_err("failed to map scatterlist\n");
449 mutex_unlock(lock);
450 return ERR_PTR(-EIO);
451 }
452
453 attach->dma_dir = dma_dir;
454
455 mutex_unlock(lock);
456
457 return sgt;
458 }
459
vb2_dma_sg_dmabuf_ops_unmap(struct dma_buf_attachment * db_attach,struct sg_table * sgt,enum dma_data_direction dma_dir)460 static void vb2_dma_sg_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
461 struct sg_table *sgt, enum dma_data_direction dma_dir)
462 {
463 /* nothing to be done here */
464 }
465
vb2_dma_sg_dmabuf_ops_release(struct dma_buf * dbuf)466 static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf)
467 {
468 /* drop reference obtained in vb2_dma_sg_get_dmabuf */
469 vb2_dma_sg_put(dbuf->priv);
470 }
471
472 static int
vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf * dbuf,enum dma_data_direction direction)473 vb2_dma_sg_dmabuf_ops_begin_cpu_access(struct dma_buf *dbuf,
474 enum dma_data_direction direction)
475 {
476 struct vb2_dma_sg_buf *buf = dbuf->priv;
477 struct sg_table *sgt = buf->dma_sgt;
478
479 dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
480 return 0;
481 }
482
483 static int
vb2_dma_sg_dmabuf_ops_end_cpu_access(struct dma_buf * dbuf,enum dma_data_direction direction)484 vb2_dma_sg_dmabuf_ops_end_cpu_access(struct dma_buf *dbuf,
485 enum dma_data_direction direction)
486 {
487 struct vb2_dma_sg_buf *buf = dbuf->priv;
488 struct sg_table *sgt = buf->dma_sgt;
489
490 dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
491 return 0;
492 }
493
vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf * dbuf,struct iosys_map * map)494 static int vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf,
495 struct iosys_map *map)
496 {
497 struct vb2_dma_sg_buf *buf = dbuf->priv;
498
499 iosys_map_set_vaddr(map, buf->vaddr);
500
501 return 0;
502 }
503
vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf * dbuf,struct vm_area_struct * vma)504 static int vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf *dbuf,
505 struct vm_area_struct *vma)
506 {
507 return vb2_dma_sg_mmap(dbuf->priv, vma);
508 }
509
510 static const struct dma_buf_ops vb2_dma_sg_dmabuf_ops = {
511 .attach = vb2_dma_sg_dmabuf_ops_attach,
512 .detach = vb2_dma_sg_dmabuf_ops_detach,
513 .map_dma_buf = vb2_dma_sg_dmabuf_ops_map,
514 .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap,
515 .begin_cpu_access = vb2_dma_sg_dmabuf_ops_begin_cpu_access,
516 .end_cpu_access = vb2_dma_sg_dmabuf_ops_end_cpu_access,
517 .vmap = vb2_dma_sg_dmabuf_ops_vmap,
518 .mmap = vb2_dma_sg_dmabuf_ops_mmap,
519 .release = vb2_dma_sg_dmabuf_ops_release,
520 };
521
vb2_dma_sg_get_dmabuf(struct vb2_buffer * vb,void * buf_priv,unsigned long flags)522 static struct dma_buf *vb2_dma_sg_get_dmabuf(struct vb2_buffer *vb,
523 void *buf_priv,
524 unsigned long flags)
525 {
526 struct vb2_dma_sg_buf *buf = buf_priv;
527 struct dma_buf *dbuf;
528 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
529
530 exp_info.ops = &vb2_dma_sg_dmabuf_ops;
531 exp_info.size = buf->size;
532 exp_info.flags = flags;
533 exp_info.priv = buf;
534
535 if (WARN_ON(!buf->dma_sgt))
536 return NULL;
537
538 dbuf = dma_buf_export(&exp_info);
539 if (IS_ERR(dbuf))
540 return NULL;
541
542 /* dmabuf keeps reference to vb2 buffer */
543 refcount_inc(&buf->refcount);
544
545 return dbuf;
546 }
547
548 /*********************************************/
549 /* callbacks for DMABUF buffers */
550 /*********************************************/
551
vb2_dma_sg_map_dmabuf(void * mem_priv)552 static int vb2_dma_sg_map_dmabuf(void *mem_priv)
553 {
554 struct vb2_dma_sg_buf *buf = mem_priv;
555 struct sg_table *sgt;
556
557 if (WARN_ON(!buf->db_attach)) {
558 pr_err("trying to pin a non attached buffer\n");
559 return -EINVAL;
560 }
561
562 if (WARN_ON(buf->dma_sgt)) {
563 pr_err("dmabuf buffer is already pinned\n");
564 return 0;
565 }
566
567 /* get the associated scatterlist for this buffer */
568 sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir);
569 if (IS_ERR(sgt)) {
570 pr_err("Error getting dmabuf scatterlist\n");
571 return -EINVAL;
572 }
573
574 buf->dma_sgt = sgt;
575 buf->vaddr = NULL;
576
577 return 0;
578 }
579
vb2_dma_sg_unmap_dmabuf(void * mem_priv)580 static void vb2_dma_sg_unmap_dmabuf(void *mem_priv)
581 {
582 struct vb2_dma_sg_buf *buf = mem_priv;
583 struct sg_table *sgt = buf->dma_sgt;
584 struct iosys_map map = IOSYS_MAP_INIT_VADDR(buf->vaddr);
585
586 if (WARN_ON(!buf->db_attach)) {
587 pr_err("trying to unpin a not attached buffer\n");
588 return;
589 }
590
591 if (WARN_ON(!sgt)) {
592 pr_err("dmabuf buffer is already unpinned\n");
593 return;
594 }
595
596 if (buf->vaddr) {
597 dma_buf_vunmap(buf->db_attach->dmabuf, &map);
598 buf->vaddr = NULL;
599 }
600 dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir);
601
602 buf->dma_sgt = NULL;
603 }
604
vb2_dma_sg_detach_dmabuf(void * mem_priv)605 static void vb2_dma_sg_detach_dmabuf(void *mem_priv)
606 {
607 struct vb2_dma_sg_buf *buf = mem_priv;
608
609 /* if vb2 works correctly you should never detach mapped buffer */
610 if (WARN_ON(buf->dma_sgt))
611 vb2_dma_sg_unmap_dmabuf(buf);
612
613 /* detach this attachment */
614 dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach);
615 kfree(buf);
616 }
617
vb2_dma_sg_attach_dmabuf(struct vb2_buffer * vb,struct device * dev,struct dma_buf * dbuf,unsigned long size)618 static void *vb2_dma_sg_attach_dmabuf(struct vb2_buffer *vb, struct device *dev,
619 struct dma_buf *dbuf, unsigned long size)
620 {
621 struct vb2_dma_sg_buf *buf;
622 struct dma_buf_attachment *dba;
623
624 if (WARN_ON(!dev))
625 return ERR_PTR(-EINVAL);
626
627 if (dbuf->size < size)
628 return ERR_PTR(-EFAULT);
629
630 buf = kzalloc(sizeof(*buf), GFP_KERNEL);
631 if (!buf)
632 return ERR_PTR(-ENOMEM);
633
634 buf->dev = dev;
635 /* create attachment for the dmabuf with the user device */
636 dba = dma_buf_attach(dbuf, buf->dev);
637 if (IS_ERR(dba)) {
638 pr_err("failed to attach dmabuf\n");
639 kfree(buf);
640 return dba;
641 }
642
643 buf->dma_dir = vb->vb2_queue->dma_dir;
644 buf->size = size;
645 buf->db_attach = dba;
646 buf->vb = vb;
647
648 return buf;
649 }
650
vb2_dma_sg_cookie(struct vb2_buffer * vb,void * buf_priv)651 static void *vb2_dma_sg_cookie(struct vb2_buffer *vb, void *buf_priv)
652 {
653 struct vb2_dma_sg_buf *buf = buf_priv;
654
655 return buf->dma_sgt;
656 }
657
658 const struct vb2_mem_ops vb2_dma_sg_memops = {
659 .alloc = vb2_dma_sg_alloc,
660 .put = vb2_dma_sg_put,
661 .get_userptr = vb2_dma_sg_get_userptr,
662 .put_userptr = vb2_dma_sg_put_userptr,
663 .prepare = vb2_dma_sg_prepare,
664 .finish = vb2_dma_sg_finish,
665 .vaddr = vb2_dma_sg_vaddr,
666 .mmap = vb2_dma_sg_mmap,
667 .num_users = vb2_dma_sg_num_users,
668 .get_dmabuf = vb2_dma_sg_get_dmabuf,
669 .map_dmabuf = vb2_dma_sg_map_dmabuf,
670 .unmap_dmabuf = vb2_dma_sg_unmap_dmabuf,
671 .attach_dmabuf = vb2_dma_sg_attach_dmabuf,
672 .detach_dmabuf = vb2_dma_sg_detach_dmabuf,
673 .cookie = vb2_dma_sg_cookie,
674 };
675 EXPORT_SYMBOL_GPL(vb2_dma_sg_memops);
676
677 MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2");
678 MODULE_AUTHOR("Andrzej Pietrasiewicz");
679 MODULE_LICENSE("GPL");
680 MODULE_IMPORT_NS(DMA_BUF);
681