Merge branches 'fixes' and 'ioremap' into for-linus
[deliverable/linux.git] / drivers / media / v4l2-core / videobuf2-dma-sg.c
CommitLineData
5ba3f757
AP
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 <andrzej.p@samsung.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/scatterlist.h>
16#include <linux/sched.h>
17#include <linux/slab.h>
18#include <linux/vmalloc.h>
19
20#include <media/videobuf2-core.h>
21#include <media/videobuf2-memops.h>
22#include <media/videobuf2-dma-sg.h>
23
ffdc78ef
HV
24static int debug;
25module_param(debug, int, 0644);
26
27#define dprintk(level, fmt, arg...) \
28 do { \
29 if (debug >= level) \
30 printk(KERN_DEBUG "vb2-dma-sg: " fmt, ## arg); \
31 } while (0)
32
0c3a14c1
HV
33struct vb2_dma_sg_conf {
34 struct device *dev;
35};
36
5ba3f757 37struct vb2_dma_sg_buf {
0c3a14c1 38 struct device *dev;
5ba3f757
AP
39 void *vaddr;
40 struct page **pages;
5ba3f757 41 int offset;
cd474037 42 enum dma_data_direction dma_dir;
22301247 43 struct sg_table sg_table;
e078b79d
HV
44 /*
45 * This will point to sg_table when used with the MMAP or USERPTR
46 * memory model, and to the dma_buf sglist when used with the
47 * DMABUF memory model.
48 */
49 struct sg_table *dma_sgt;
22301247
RR
50 size_t size;
51 unsigned int num_pages;
5ba3f757
AP
52 atomic_t refcount;
53 struct vb2_vmarea_handler handler;
50ac952d 54 struct vm_area_struct *vma;
e078b79d
HV
55
56 struct dma_buf_attachment *db_attach;
5ba3f757
AP
57};
58
59static void vb2_dma_sg_put(void *buf_priv);
60
df237281
RR
61static int vb2_dma_sg_alloc_compacted(struct vb2_dma_sg_buf *buf,
62 gfp_t gfp_flags)
63{
64 unsigned int last_page = 0;
22301247 65 int size = buf->size;
df237281
RR
66
67 while (size > 0) {
68 struct page *pages;
69 int order;
70 int i;
71
72 order = get_order(size);
73 /* Dont over allocate*/
74 if ((PAGE_SIZE << order) > size)
75 order--;
76
77 pages = NULL;
78 while (!pages) {
79 pages = alloc_pages(GFP_KERNEL | __GFP_ZERO |
80 __GFP_NOWARN | gfp_flags, order);
81 if (pages)
82 break;
83
84 if (order == 0) {
85 while (last_page--)
86 __free_page(buf->pages[last_page]);
87 return -ENOMEM;
88 }
89 order--;
90 }
91
92 split_page(pages, order);
22301247
RR
93 for (i = 0; i < (1 << order); i++)
94 buf->pages[last_page++] = &pages[i];
df237281
RR
95
96 size -= PAGE_SIZE << order;
97 }
98
99 return 0;
100}
101
d935c57e
HV
102static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size,
103 enum dma_data_direction dma_dir, gfp_t gfp_flags)
5ba3f757 104{
0c3a14c1 105 struct vb2_dma_sg_conf *conf = alloc_ctx;
5ba3f757 106 struct vb2_dma_sg_buf *buf;
d790b7ed 107 struct sg_table *sgt;
df237281 108 int ret;
22301247 109 int num_pages;
251a79f8
HV
110 DEFINE_DMA_ATTRS(attrs);
111
112 dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
5ba3f757 113
0c3a14c1
HV
114 if (WARN_ON(alloc_ctx == NULL))
115 return NULL;
5ba3f757
AP
116 buf = kzalloc(sizeof *buf, GFP_KERNEL);
117 if (!buf)
118 return NULL;
119
120 buf->vaddr = NULL;
d935c57e 121 buf->dma_dir = dma_dir;
5ba3f757 122 buf->offset = 0;
22301247 123 buf->size = size;
7f841459 124 /* size is already page aligned */
22301247 125 buf->num_pages = size >> PAGE_SHIFT;
e078b79d 126 buf->dma_sgt = &buf->sg_table;
5ba3f757 127
22301247 128 buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
5ba3f757
AP
129 GFP_KERNEL);
130 if (!buf->pages)
131 goto fail_pages_array_alloc;
132
df237281
RR
133 ret = vb2_dma_sg_alloc_compacted(buf, gfp_flags);
134 if (ret)
135 goto fail_pages_alloc;
5ba3f757 136
e078b79d 137 ret = sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
47bc59c5 138 buf->num_pages, 0, size, GFP_KERNEL);
22301247
RR
139 if (ret)
140 goto fail_table_alloc;
141
0c3a14c1
HV
142 /* Prevent the device from being released while the buffer is used */
143 buf->dev = get_device(conf->dev);
d790b7ed
HV
144
145 sgt = &buf->sg_table;
251a79f8
HV
146 /*
147 * No need to sync to the device, this will happen later when the
148 * prepare() memop is called.
149 */
6a5d77cb
RR
150 sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
151 buf->dma_dir, &attrs);
152 if (!sgt->nents)
d790b7ed 153 goto fail_map;
d790b7ed 154
5ba3f757
AP
155 buf->handler.refcount = &buf->refcount;
156 buf->handler.put = vb2_dma_sg_put;
157 buf->handler.arg = buf;
158
159 atomic_inc(&buf->refcount);
160
ffdc78ef 161 dprintk(1, "%s: Allocated buffer of %d pages\n",
22301247 162 __func__, buf->num_pages);
5ba3f757
AP
163 return buf;
164
d790b7ed
HV
165fail_map:
166 put_device(buf->dev);
e078b79d 167 sg_free_table(buf->dma_sgt);
22301247
RR
168fail_table_alloc:
169 num_pages = buf->num_pages;
170 while (num_pages--)
171 __free_page(buf->pages[num_pages]);
5ba3f757 172fail_pages_alloc:
a9bb36aa 173 kfree(buf->pages);
5ba3f757 174fail_pages_array_alloc:
5ba3f757
AP
175 kfree(buf);
176 return NULL;
177}
178
179static void vb2_dma_sg_put(void *buf_priv)
180{
181 struct vb2_dma_sg_buf *buf = buf_priv;
d790b7ed 182 struct sg_table *sgt = &buf->sg_table;
22301247 183 int i = buf->num_pages;
5ba3f757
AP
184
185 if (atomic_dec_and_test(&buf->refcount)) {
251a79f8
HV
186 DEFINE_DMA_ATTRS(attrs);
187
188 dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
ffdc78ef 189 dprintk(1, "%s: Freeing buffer of %d pages\n", __func__,
22301247 190 buf->num_pages);
6a5d77cb 191 dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
251a79f8 192 buf->dma_dir, &attrs);
5ba3f757 193 if (buf->vaddr)
22301247 194 vm_unmap_ram(buf->vaddr, buf->num_pages);
e078b79d 195 sg_free_table(buf->dma_sgt);
5ba3f757
AP
196 while (--i >= 0)
197 __free_page(buf->pages[i]);
198 kfree(buf->pages);
0c3a14c1 199 put_device(buf->dev);
5ba3f757
AP
200 kfree(buf);
201 }
202}
203
d790b7ed
HV
204static void vb2_dma_sg_prepare(void *buf_priv)
205{
206 struct vb2_dma_sg_buf *buf = buf_priv;
e078b79d
HV
207 struct sg_table *sgt = buf->dma_sgt;
208
209 /* DMABUF exporter will flush the cache for us */
210 if (buf->db_attach)
211 return;
d790b7ed
HV
212
213 dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
214}
215
216static void vb2_dma_sg_finish(void *buf_priv)
217{
218 struct vb2_dma_sg_buf *buf = buf_priv;
e078b79d
HV
219 struct sg_table *sgt = buf->dma_sgt;
220
221 /* DMABUF exporter will flush the cache for us */
222 if (buf->db_attach)
223 return;
d790b7ed
HV
224
225 dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
226}
227
50ac952d
RR
228static inline int vma_is_io(struct vm_area_struct *vma)
229{
230 return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
231}
232
5ba3f757 233static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
cd474037
HV
234 unsigned long size,
235 enum dma_data_direction dma_dir)
5ba3f757 236{
d790b7ed 237 struct vb2_dma_sg_conf *conf = alloc_ctx;
5ba3f757
AP
238 struct vb2_dma_sg_buf *buf;
239 unsigned long first, last;
22301247 240 int num_pages_from_user;
50ac952d 241 struct vm_area_struct *vma;
d790b7ed 242 struct sg_table *sgt;
251a79f8
HV
243 DEFINE_DMA_ATTRS(attrs);
244
245 dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
5ba3f757
AP
246
247 buf = kzalloc(sizeof *buf, GFP_KERNEL);
248 if (!buf)
249 return NULL;
250
251 buf->vaddr = NULL;
d790b7ed 252 buf->dev = conf->dev;
cd474037 253 buf->dma_dir = dma_dir;
5ba3f757 254 buf->offset = vaddr & ~PAGE_MASK;
22301247 255 buf->size = size;
e078b79d 256 buf->dma_sgt = &buf->sg_table;
5ba3f757
AP
257
258 first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
259 last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
22301247 260 buf->num_pages = last - first + 1;
5ba3f757 261
22301247 262 buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
5ba3f757
AP
263 GFP_KERNEL);
264 if (!buf->pages)
64c832a4 265 goto userptr_fail_alloc_pages;
5ba3f757 266
50ac952d
RR
267 vma = find_vma(current->mm, vaddr);
268 if (!vma) {
269 dprintk(1, "no vma for address %lu\n", vaddr);
270 goto userptr_fail_find_vma;
271 }
272
273 if (vma->vm_end < vaddr + size) {
274 dprintk(1, "vma at %lu is too small for %lu bytes\n",
275 vaddr, size);
276 goto userptr_fail_find_vma;
277 }
278
279 buf->vma = vb2_get_vma(vma);
280 if (!buf->vma) {
281 dprintk(1, "failed to copy vma\n");
282 goto userptr_fail_find_vma;
283 }
284
285 if (vma_is_io(buf->vma)) {
286 for (num_pages_from_user = 0;
287 num_pages_from_user < buf->num_pages;
288 ++num_pages_from_user, vaddr += PAGE_SIZE) {
289 unsigned long pfn;
290
227ae227 291 if (follow_pfn(vma, vaddr, &pfn)) {
50ac952d
RR
292 dprintk(1, "no page for address %lu\n", vaddr);
293 break;
294 }
295 buf->pages[num_pages_from_user] = pfn_to_page(pfn);
296 }
297 } else
298 num_pages_from_user = get_user_pages(current, current->mm,
5ba3f757 299 vaddr & PAGE_MASK,
22301247 300 buf->num_pages,
cd474037 301 buf->dma_dir == DMA_FROM_DEVICE,
5ba3f757
AP
302 1, /* force */
303 buf->pages,
304 NULL);
b037c0fd 305
22301247 306 if (num_pages_from_user != buf->num_pages)
5ba3f757
AP
307 goto userptr_fail_get_user_pages;
308
e078b79d 309 if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
22301247
RR
310 buf->num_pages, buf->offset, size, 0))
311 goto userptr_fail_alloc_table_from_pages;
312
d790b7ed 313 sgt = &buf->sg_table;
251a79f8
HV
314 /*
315 * No need to sync to the device, this will happen later when the
316 * prepare() memop is called.
317 */
6a5d77cb
RR
318 sgt->nents = dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents,
319 buf->dma_dir, &attrs);
320 if (!sgt->nents)
d790b7ed 321 goto userptr_fail_map;
6a5d77cb 322
5ba3f757
AP
323 return buf;
324
d790b7ed
HV
325userptr_fail_map:
326 sg_free_table(&buf->sg_table);
22301247 327userptr_fail_alloc_table_from_pages:
5ba3f757 328userptr_fail_get_user_pages:
ffdc78ef 329 dprintk(1, "get_user_pages requested/got: %d/%d]\n",
202dfbdc 330 buf->num_pages, num_pages_from_user);
50ac952d
RR
331 if (!vma_is_io(buf->vma))
332 while (--num_pages_from_user >= 0)
333 put_page(buf->pages[num_pages_from_user]);
334 vb2_put_vma(buf->vma);
335userptr_fail_find_vma:
a9bb36aa 336 kfree(buf->pages);
64c832a4 337userptr_fail_alloc_pages:
5ba3f757
AP
338 kfree(buf);
339 return NULL;
340}
341
342/*
343 * @put_userptr: inform the allocator that a USERPTR buffer will no longer
344 * be used
345 */
346static void vb2_dma_sg_put_userptr(void *buf_priv)
347{
348 struct vb2_dma_sg_buf *buf = buf_priv;
d790b7ed 349 struct sg_table *sgt = &buf->sg_table;
22301247 350 int i = buf->num_pages;
251a79f8
HV
351 DEFINE_DMA_ATTRS(attrs);
352
353 dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
5ba3f757 354
ffdc78ef 355 dprintk(1, "%s: Releasing userspace buffer of %d pages\n",
22301247 356 __func__, buf->num_pages);
6a5d77cb
RR
357 dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->orig_nents, buf->dma_dir,
358 &attrs);
5ba3f757 359 if (buf->vaddr)
22301247 360 vm_unmap_ram(buf->vaddr, buf->num_pages);
e078b79d 361 sg_free_table(buf->dma_sgt);
5ba3f757 362 while (--i >= 0) {
cd474037 363 if (buf->dma_dir == DMA_FROM_DEVICE)
5ba3f757 364 set_page_dirty_lock(buf->pages[i]);
50ac952d
RR
365 if (!vma_is_io(buf->vma))
366 put_page(buf->pages[i]);
5ba3f757 367 }
5ba3f757 368 kfree(buf->pages);
50ac952d 369 vb2_put_vma(buf->vma);
5ba3f757
AP
370 kfree(buf);
371}
372
373static void *vb2_dma_sg_vaddr(void *buf_priv)
374{
375 struct vb2_dma_sg_buf *buf = buf_priv;
376
377 BUG_ON(!buf);
378
e078b79d
HV
379 if (!buf->vaddr) {
380 if (buf->db_attach)
381 buf->vaddr = dma_buf_vmap(buf->db_attach->dmabuf);
382 else
383 buf->vaddr = vm_map_ram(buf->pages,
384 buf->num_pages, -1, PAGE_KERNEL);
385 }
5ba3f757
AP
386
387 /* add offset in case userptr is not page-aligned */
e078b79d 388 return buf->vaddr ? buf->vaddr + buf->offset : NULL;
5ba3f757
AP
389}
390
391static unsigned int vb2_dma_sg_num_users(void *buf_priv)
392{
393 struct vb2_dma_sg_buf *buf = buf_priv;
394
395 return atomic_read(&buf->refcount);
396}
397
398static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma)
399{
400 struct vb2_dma_sg_buf *buf = buf_priv;
401 unsigned long uaddr = vma->vm_start;
402 unsigned long usize = vma->vm_end - vma->vm_start;
403 int i = 0;
404
405 if (!buf) {
406 printk(KERN_ERR "No memory to map\n");
407 return -EINVAL;
408 }
409
410 do {
411 int ret;
412
413 ret = vm_insert_page(vma, uaddr, buf->pages[i++]);
414 if (ret) {
415 printk(KERN_ERR "Remapping memory, error: %d\n", ret);
416 return ret;
417 }
418
419 uaddr += PAGE_SIZE;
420 usize -= PAGE_SIZE;
421 } while (usize > 0);
422
423
424 /*
425 * Use common vm_area operations to track buffer refcount.
426 */
427 vma->vm_private_data = &buf->handler;
428 vma->vm_ops = &vb2_common_vm_ops;
429
430 vma->vm_ops->open(vma);
431
432 return 0;
433}
434
041c7b6a
HV
435/*********************************************/
436/* DMABUF ops for exporters */
437/*********************************************/
438
439struct vb2_dma_sg_attachment {
440 struct sg_table sgt;
441 enum dma_data_direction dma_dir;
442};
443
444static int vb2_dma_sg_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
445 struct dma_buf_attachment *dbuf_attach)
446{
447 struct vb2_dma_sg_attachment *attach;
448 unsigned int i;
449 struct scatterlist *rd, *wr;
450 struct sg_table *sgt;
451 struct vb2_dma_sg_buf *buf = dbuf->priv;
452 int ret;
453
454 attach = kzalloc(sizeof(*attach), GFP_KERNEL);
455 if (!attach)
456 return -ENOMEM;
457
458 sgt = &attach->sgt;
459 /* Copy the buf->base_sgt scatter list to the attachment, as we can't
460 * map the same scatter list to multiple attachments at the same time.
461 */
462 ret = sg_alloc_table(sgt, buf->dma_sgt->orig_nents, GFP_KERNEL);
463 if (ret) {
464 kfree(attach);
465 return -ENOMEM;
466 }
467
468 rd = buf->dma_sgt->sgl;
469 wr = sgt->sgl;
470 for (i = 0; i < sgt->orig_nents; ++i) {
471 sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
472 rd = sg_next(rd);
473 wr = sg_next(wr);
474 }
475
476 attach->dma_dir = DMA_NONE;
477 dbuf_attach->priv = attach;
478
479 return 0;
480}
481
482static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf,
483 struct dma_buf_attachment *db_attach)
484{
485 struct vb2_dma_sg_attachment *attach = db_attach->priv;
486 struct sg_table *sgt;
487
488 if (!attach)
489 return;
490
491 sgt = &attach->sgt;
492
493 /* release the scatterlist cache */
494 if (attach->dma_dir != DMA_NONE)
495 dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
496 attach->dma_dir);
497 sg_free_table(sgt);
498 kfree(attach);
499 db_attach->priv = NULL;
500}
501
502static struct sg_table *vb2_dma_sg_dmabuf_ops_map(
503 struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
504{
505 struct vb2_dma_sg_attachment *attach = db_attach->priv;
506 /* stealing dmabuf mutex to serialize map/unmap operations */
507 struct mutex *lock = &db_attach->dmabuf->lock;
508 struct sg_table *sgt;
041c7b6a
HV
509
510 mutex_lock(lock);
511
512 sgt = &attach->sgt;
513 /* return previously mapped sg table */
514 if (attach->dma_dir == dma_dir) {
515 mutex_unlock(lock);
516 return sgt;
517 }
518
519 /* release any previous cache */
520 if (attach->dma_dir != DMA_NONE) {
521 dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
522 attach->dma_dir);
523 attach->dma_dir = DMA_NONE;
524 }
525
526 /* mapping to the client with new direction */
6a5d77cb
RR
527 sgt->nents = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
528 dma_dir);
529 if (!sgt->nents) {
041c7b6a
HV
530 pr_err("failed to map scatterlist\n");
531 mutex_unlock(lock);
532 return ERR_PTR(-EIO);
533 }
534
535 attach->dma_dir = dma_dir;
536
537 mutex_unlock(lock);
538
539 return sgt;
540}
541
542static void vb2_dma_sg_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
543 struct sg_table *sgt, enum dma_data_direction dma_dir)
544{
545 /* nothing to be done here */
546}
547
548static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf)
549{
550 /* drop reference obtained in vb2_dma_sg_get_dmabuf */
551 vb2_dma_sg_put(dbuf->priv);
552}
553
554static void *vb2_dma_sg_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum)
555{
556 struct vb2_dma_sg_buf *buf = dbuf->priv;
557
558 return buf->vaddr ? buf->vaddr + pgnum * PAGE_SIZE : NULL;
559}
560
561static void *vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf)
562{
563 struct vb2_dma_sg_buf *buf = dbuf->priv;
564
565 return vb2_dma_sg_vaddr(buf);
566}
567
568static int vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf *dbuf,
569 struct vm_area_struct *vma)
570{
571 return vb2_dma_sg_mmap(dbuf->priv, vma);
572}
573
574static struct dma_buf_ops vb2_dma_sg_dmabuf_ops = {
575 .attach = vb2_dma_sg_dmabuf_ops_attach,
576 .detach = vb2_dma_sg_dmabuf_ops_detach,
577 .map_dma_buf = vb2_dma_sg_dmabuf_ops_map,
578 .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap,
579 .kmap = vb2_dma_sg_dmabuf_ops_kmap,
580 .kmap_atomic = vb2_dma_sg_dmabuf_ops_kmap,
581 .vmap = vb2_dma_sg_dmabuf_ops_vmap,
582 .mmap = vb2_dma_sg_dmabuf_ops_mmap,
583 .release = vb2_dma_sg_dmabuf_ops_release,
584};
585
586static struct dma_buf *vb2_dma_sg_get_dmabuf(void *buf_priv, unsigned long flags)
587{
588 struct vb2_dma_sg_buf *buf = buf_priv;
589 struct dma_buf *dbuf;
d8fbe341
SS
590 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
591
592 exp_info.ops = &vb2_dma_sg_dmabuf_ops;
593 exp_info.size = buf->size;
594 exp_info.flags = flags;
595 exp_info.priv = buf;
041c7b6a
HV
596
597 if (WARN_ON(!buf->dma_sgt))
598 return NULL;
599
d8fbe341 600 dbuf = dma_buf_export(&exp_info);
041c7b6a
HV
601 if (IS_ERR(dbuf))
602 return NULL;
603
604 /* dmabuf keeps reference to vb2 buffer */
605 atomic_inc(&buf->refcount);
606
607 return dbuf;
608}
609
e078b79d
HV
610/*********************************************/
611/* callbacks for DMABUF buffers */
612/*********************************************/
613
614static int vb2_dma_sg_map_dmabuf(void *mem_priv)
615{
616 struct vb2_dma_sg_buf *buf = mem_priv;
617 struct sg_table *sgt;
618
619 if (WARN_ON(!buf->db_attach)) {
620 pr_err("trying to pin a non attached buffer\n");
621 return -EINVAL;
622 }
623
624 if (WARN_ON(buf->dma_sgt)) {
625 pr_err("dmabuf buffer is already pinned\n");
626 return 0;
627 }
628
629 /* get the associated scatterlist for this buffer */
630 sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir);
631 if (IS_ERR(sgt)) {
632 pr_err("Error getting dmabuf scatterlist\n");
633 return -EINVAL;
634 }
635
636 buf->dma_sgt = sgt;
637 buf->vaddr = NULL;
638
639 return 0;
640}
641
642static void vb2_dma_sg_unmap_dmabuf(void *mem_priv)
643{
644 struct vb2_dma_sg_buf *buf = mem_priv;
645 struct sg_table *sgt = buf->dma_sgt;
646
647 if (WARN_ON(!buf->db_attach)) {
648 pr_err("trying to unpin a not attached buffer\n");
649 return;
650 }
651
652 if (WARN_ON(!sgt)) {
653 pr_err("dmabuf buffer is already unpinned\n");
654 return;
655 }
656
657 if (buf->vaddr) {
658 dma_buf_vunmap(buf->db_attach->dmabuf, buf->vaddr);
659 buf->vaddr = NULL;
660 }
661 dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir);
662
663 buf->dma_sgt = NULL;
664}
665
666static void vb2_dma_sg_detach_dmabuf(void *mem_priv)
667{
668 struct vb2_dma_sg_buf *buf = mem_priv;
669
670 /* if vb2 works correctly you should never detach mapped buffer */
671 if (WARN_ON(buf->dma_sgt))
672 vb2_dma_sg_unmap_dmabuf(buf);
673
674 /* detach this attachment */
675 dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach);
676 kfree(buf);
677}
678
679static void *vb2_dma_sg_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
680 unsigned long size, enum dma_data_direction dma_dir)
681{
682 struct vb2_dma_sg_conf *conf = alloc_ctx;
683 struct vb2_dma_sg_buf *buf;
684 struct dma_buf_attachment *dba;
685
686 if (dbuf->size < size)
687 return ERR_PTR(-EFAULT);
688
689 buf = kzalloc(sizeof(*buf), GFP_KERNEL);
690 if (!buf)
691 return ERR_PTR(-ENOMEM);
692
693 buf->dev = conf->dev;
694 /* create attachment for the dmabuf with the user device */
695 dba = dma_buf_attach(dbuf, buf->dev);
696 if (IS_ERR(dba)) {
697 pr_err("failed to attach dmabuf\n");
698 kfree(buf);
699 return dba;
700 }
701
702 buf->dma_dir = dma_dir;
703 buf->size = size;
704 buf->db_attach = dba;
705
706 return buf;
707}
708
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709static void *vb2_dma_sg_cookie(void *buf_priv)
710{
711 struct vb2_dma_sg_buf *buf = buf_priv;
712
e078b79d 713 return buf->dma_sgt;
5ba3f757
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714}
715
716const struct vb2_mem_ops vb2_dma_sg_memops = {
717 .alloc = vb2_dma_sg_alloc,
718 .put = vb2_dma_sg_put,
719 .get_userptr = vb2_dma_sg_get_userptr,
720 .put_userptr = vb2_dma_sg_put_userptr,
d790b7ed
HV
721 .prepare = vb2_dma_sg_prepare,
722 .finish = vb2_dma_sg_finish,
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723 .vaddr = vb2_dma_sg_vaddr,
724 .mmap = vb2_dma_sg_mmap,
725 .num_users = vb2_dma_sg_num_users,
041c7b6a 726 .get_dmabuf = vb2_dma_sg_get_dmabuf,
e078b79d
HV
727 .map_dmabuf = vb2_dma_sg_map_dmabuf,
728 .unmap_dmabuf = vb2_dma_sg_unmap_dmabuf,
729 .attach_dmabuf = vb2_dma_sg_attach_dmabuf,
730 .detach_dmabuf = vb2_dma_sg_detach_dmabuf,
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731 .cookie = vb2_dma_sg_cookie,
732};
733EXPORT_SYMBOL_GPL(vb2_dma_sg_memops);
734
0c3a14c1
HV
735void *vb2_dma_sg_init_ctx(struct device *dev)
736{
737 struct vb2_dma_sg_conf *conf;
738
739 conf = kzalloc(sizeof(*conf), GFP_KERNEL);
740 if (!conf)
741 return ERR_PTR(-ENOMEM);
742
743 conf->dev = dev;
744
745 return conf;
746}
747EXPORT_SYMBOL_GPL(vb2_dma_sg_init_ctx);
748
749void vb2_dma_sg_cleanup_ctx(void *alloc_ctx)
750{
751 if (!IS_ERR_OR_NULL(alloc_ctx))
752 kfree(alloc_ctx);
753}
754EXPORT_SYMBOL_GPL(vb2_dma_sg_cleanup_ctx);
755
5ba3f757
AP
756MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2");
757MODULE_AUTHOR("Andrzej Pietrasiewicz");
758MODULE_LICENSE("GPL");
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