Commit | Line | Data |
---|---|---|
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 |
24 | static int debug; |
25 | module_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 |
33 | struct vb2_dma_sg_conf { |
34 | struct device *dev; | |
35 | }; | |
36 | ||
5ba3f757 | 37 | struct 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 | ||
59 | static void vb2_dma_sg_put(void *buf_priv); | |
60 | ||
df237281 RR |
61 | static 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 |
102 | static 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 | */ | |
150 | if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents, | |
151 | buf->dma_dir, &attrs) == 0) | |
d790b7ed | 152 | goto fail_map; |
d790b7ed | 153 | |
5ba3f757 AP |
154 | buf->handler.refcount = &buf->refcount; |
155 | buf->handler.put = vb2_dma_sg_put; | |
156 | buf->handler.arg = buf; | |
157 | ||
158 | atomic_inc(&buf->refcount); | |
159 | ||
ffdc78ef | 160 | dprintk(1, "%s: Allocated buffer of %d pages\n", |
22301247 | 161 | __func__, buf->num_pages); |
5ba3f757 AP |
162 | return buf; |
163 | ||
d790b7ed HV |
164 | fail_map: |
165 | put_device(buf->dev); | |
e078b79d | 166 | sg_free_table(buf->dma_sgt); |
22301247 RR |
167 | fail_table_alloc: |
168 | num_pages = buf->num_pages; | |
169 | while (num_pages--) | |
170 | __free_page(buf->pages[num_pages]); | |
5ba3f757 | 171 | fail_pages_alloc: |
a9bb36aa | 172 | kfree(buf->pages); |
5ba3f757 | 173 | fail_pages_array_alloc: |
5ba3f757 AP |
174 | kfree(buf); |
175 | return NULL; | |
176 | } | |
177 | ||
178 | static void vb2_dma_sg_put(void *buf_priv) | |
179 | { | |
180 | struct vb2_dma_sg_buf *buf = buf_priv; | |
d790b7ed | 181 | struct sg_table *sgt = &buf->sg_table; |
22301247 | 182 | int i = buf->num_pages; |
5ba3f757 AP |
183 | |
184 | if (atomic_dec_and_test(&buf->refcount)) { | |
251a79f8 HV |
185 | DEFINE_DMA_ATTRS(attrs); |
186 | ||
187 | dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); | |
ffdc78ef | 188 | dprintk(1, "%s: Freeing buffer of %d pages\n", __func__, |
22301247 | 189 | buf->num_pages); |
251a79f8 HV |
190 | dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents, |
191 | buf->dma_dir, &attrs); | |
5ba3f757 | 192 | if (buf->vaddr) |
22301247 | 193 | vm_unmap_ram(buf->vaddr, buf->num_pages); |
e078b79d | 194 | sg_free_table(buf->dma_sgt); |
5ba3f757 AP |
195 | while (--i >= 0) |
196 | __free_page(buf->pages[i]); | |
197 | kfree(buf->pages); | |
0c3a14c1 | 198 | put_device(buf->dev); |
5ba3f757 AP |
199 | kfree(buf); |
200 | } | |
201 | } | |
202 | ||
d790b7ed HV |
203 | static void vb2_dma_sg_prepare(void *buf_priv) |
204 | { | |
205 | struct vb2_dma_sg_buf *buf = buf_priv; | |
e078b79d HV |
206 | struct sg_table *sgt = buf->dma_sgt; |
207 | ||
208 | /* DMABUF exporter will flush the cache for us */ | |
209 | if (buf->db_attach) | |
210 | return; | |
d790b7ed HV |
211 | |
212 | dma_sync_sg_for_device(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); | |
213 | } | |
214 | ||
215 | static void vb2_dma_sg_finish(void *buf_priv) | |
216 | { | |
217 | struct vb2_dma_sg_buf *buf = buf_priv; | |
e078b79d HV |
218 | struct sg_table *sgt = buf->dma_sgt; |
219 | ||
220 | /* DMABUF exporter will flush the cache for us */ | |
221 | if (buf->db_attach) | |
222 | return; | |
d790b7ed HV |
223 | |
224 | dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir); | |
225 | } | |
226 | ||
50ac952d RR |
227 | static inline int vma_is_io(struct vm_area_struct *vma) |
228 | { | |
229 | return !!(vma->vm_flags & (VM_IO | VM_PFNMAP)); | |
230 | } | |
231 | ||
5ba3f757 | 232 | static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr, |
cd474037 HV |
233 | unsigned long size, |
234 | enum dma_data_direction dma_dir) | |
5ba3f757 | 235 | { |
d790b7ed | 236 | struct vb2_dma_sg_conf *conf = alloc_ctx; |
5ba3f757 AP |
237 | struct vb2_dma_sg_buf *buf; |
238 | unsigned long first, last; | |
22301247 | 239 | int num_pages_from_user; |
50ac952d | 240 | struct vm_area_struct *vma; |
d790b7ed | 241 | struct sg_table *sgt; |
251a79f8 HV |
242 | DEFINE_DMA_ATTRS(attrs); |
243 | ||
244 | dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); | |
5ba3f757 AP |
245 | |
246 | buf = kzalloc(sizeof *buf, GFP_KERNEL); | |
247 | if (!buf) | |
248 | return NULL; | |
249 | ||
250 | buf->vaddr = NULL; | |
d790b7ed | 251 | buf->dev = conf->dev; |
cd474037 | 252 | buf->dma_dir = dma_dir; |
5ba3f757 | 253 | buf->offset = vaddr & ~PAGE_MASK; |
22301247 | 254 | buf->size = size; |
e078b79d | 255 | buf->dma_sgt = &buf->sg_table; |
5ba3f757 AP |
256 | |
257 | first = (vaddr & PAGE_MASK) >> PAGE_SHIFT; | |
258 | last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT; | |
22301247 | 259 | buf->num_pages = last - first + 1; |
5ba3f757 | 260 | |
22301247 | 261 | buf->pages = kzalloc(buf->num_pages * sizeof(struct page *), |
5ba3f757 AP |
262 | GFP_KERNEL); |
263 | if (!buf->pages) | |
64c832a4 | 264 | goto userptr_fail_alloc_pages; |
5ba3f757 | 265 | |
48b25a3a | 266 | down_read(¤t->mm->mmap_sem); |
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); | |
48b25a3a | 305 | up_read(¤t->mm->mmap_sem); |
b037c0fd | 306 | |
22301247 | 307 | if (num_pages_from_user != buf->num_pages) |
5ba3f757 AP |
308 | goto userptr_fail_get_user_pages; |
309 | ||
e078b79d | 310 | if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages, |
22301247 RR |
311 | buf->num_pages, buf->offset, size, 0)) |
312 | goto userptr_fail_alloc_table_from_pages; | |
313 | ||
d790b7ed | 314 | sgt = &buf->sg_table; |
251a79f8 HV |
315 | /* |
316 | * No need to sync to the device, this will happen later when the | |
317 | * prepare() memop is called. | |
318 | */ | |
319 | if (dma_map_sg_attrs(buf->dev, sgt->sgl, sgt->nents, | |
320 | buf->dma_dir, &attrs) == 0) | |
d790b7ed | 321 | goto userptr_fail_map; |
5ba3f757 AP |
322 | return buf; |
323 | ||
d790b7ed HV |
324 | userptr_fail_map: |
325 | sg_free_table(&buf->sg_table); | |
22301247 | 326 | userptr_fail_alloc_table_from_pages: |
5ba3f757 | 327 | userptr_fail_get_user_pages: |
ffdc78ef | 328 | dprintk(1, "get_user_pages requested/got: %d/%d]\n", |
202dfbdc | 329 | buf->num_pages, num_pages_from_user); |
50ac952d RR |
330 | if (!vma_is_io(buf->vma)) |
331 | while (--num_pages_from_user >= 0) | |
332 | put_page(buf->pages[num_pages_from_user]); | |
48b25a3a | 333 | down_read(¤t->mm->mmap_sem); |
50ac952d RR |
334 | vb2_put_vma(buf->vma); |
335 | userptr_fail_find_vma: | |
48b25a3a | 336 | up_read(¤t->mm->mmap_sem); |
a9bb36aa | 337 | kfree(buf->pages); |
64c832a4 | 338 | userptr_fail_alloc_pages: |
5ba3f757 AP |
339 | kfree(buf); |
340 | return NULL; | |
341 | } | |
342 | ||
343 | /* | |
344 | * @put_userptr: inform the allocator that a USERPTR buffer will no longer | |
345 | * be used | |
346 | */ | |
347 | static void vb2_dma_sg_put_userptr(void *buf_priv) | |
348 | { | |
349 | struct vb2_dma_sg_buf *buf = buf_priv; | |
d790b7ed | 350 | struct sg_table *sgt = &buf->sg_table; |
22301247 | 351 | int i = buf->num_pages; |
251a79f8 HV |
352 | DEFINE_DMA_ATTRS(attrs); |
353 | ||
354 | dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs); | |
5ba3f757 | 355 | |
ffdc78ef | 356 | dprintk(1, "%s: Releasing userspace buffer of %d pages\n", |
22301247 | 357 | __func__, buf->num_pages); |
251a79f8 | 358 | dma_unmap_sg_attrs(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir, &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); |
48b25a3a | 369 | down_read(¤t->mm->mmap_sem); |
50ac952d | 370 | vb2_put_vma(buf->vma); |
48b25a3a | 371 | up_read(¤t->mm->mmap_sem); |
5ba3f757 AP |
372 | kfree(buf); |
373 | } | |
374 | ||
375 | static void *vb2_dma_sg_vaddr(void *buf_priv) | |
376 | { | |
377 | struct vb2_dma_sg_buf *buf = buf_priv; | |
378 | ||
379 | BUG_ON(!buf); | |
380 | ||
e078b79d HV |
381 | if (!buf->vaddr) { |
382 | if (buf->db_attach) | |
383 | buf->vaddr = dma_buf_vmap(buf->db_attach->dmabuf); | |
384 | else | |
385 | buf->vaddr = vm_map_ram(buf->pages, | |
386 | buf->num_pages, -1, PAGE_KERNEL); | |
387 | } | |
5ba3f757 AP |
388 | |
389 | /* add offset in case userptr is not page-aligned */ | |
e078b79d | 390 | return buf->vaddr ? buf->vaddr + buf->offset : NULL; |
5ba3f757 AP |
391 | } |
392 | ||
393 | static unsigned int vb2_dma_sg_num_users(void *buf_priv) | |
394 | { | |
395 | struct vb2_dma_sg_buf *buf = buf_priv; | |
396 | ||
397 | return atomic_read(&buf->refcount); | |
398 | } | |
399 | ||
400 | static int vb2_dma_sg_mmap(void *buf_priv, struct vm_area_struct *vma) | |
401 | { | |
402 | struct vb2_dma_sg_buf *buf = buf_priv; | |
403 | unsigned long uaddr = vma->vm_start; | |
404 | unsigned long usize = vma->vm_end - vma->vm_start; | |
405 | int i = 0; | |
406 | ||
407 | if (!buf) { | |
408 | printk(KERN_ERR "No memory to map\n"); | |
409 | return -EINVAL; | |
410 | } | |
411 | ||
412 | do { | |
413 | int ret; | |
414 | ||
415 | ret = vm_insert_page(vma, uaddr, buf->pages[i++]); | |
416 | if (ret) { | |
417 | printk(KERN_ERR "Remapping memory, error: %d\n", ret); | |
418 | return ret; | |
419 | } | |
420 | ||
421 | uaddr += PAGE_SIZE; | |
422 | usize -= PAGE_SIZE; | |
423 | } while (usize > 0); | |
424 | ||
425 | ||
426 | /* | |
427 | * Use common vm_area operations to track buffer refcount. | |
428 | */ | |
429 | vma->vm_private_data = &buf->handler; | |
430 | vma->vm_ops = &vb2_common_vm_ops; | |
431 | ||
432 | vma->vm_ops->open(vma); | |
433 | ||
434 | return 0; | |
435 | } | |
436 | ||
041c7b6a HV |
437 | /*********************************************/ |
438 | /* DMABUF ops for exporters */ | |
439 | /*********************************************/ | |
440 | ||
441 | struct vb2_dma_sg_attachment { | |
442 | struct sg_table sgt; | |
443 | enum dma_data_direction dma_dir; | |
444 | }; | |
445 | ||
446 | static int vb2_dma_sg_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev, | |
447 | struct dma_buf_attachment *dbuf_attach) | |
448 | { | |
449 | struct vb2_dma_sg_attachment *attach; | |
450 | unsigned int i; | |
451 | struct scatterlist *rd, *wr; | |
452 | struct sg_table *sgt; | |
453 | struct vb2_dma_sg_buf *buf = dbuf->priv; | |
454 | int ret; | |
455 | ||
456 | attach = kzalloc(sizeof(*attach), GFP_KERNEL); | |
457 | if (!attach) | |
458 | return -ENOMEM; | |
459 | ||
460 | sgt = &attach->sgt; | |
461 | /* Copy the buf->base_sgt scatter list to the attachment, as we can't | |
462 | * map the same scatter list to multiple attachments at the same time. | |
463 | */ | |
464 | ret = sg_alloc_table(sgt, buf->dma_sgt->orig_nents, GFP_KERNEL); | |
465 | if (ret) { | |
466 | kfree(attach); | |
467 | return -ENOMEM; | |
468 | } | |
469 | ||
470 | rd = buf->dma_sgt->sgl; | |
471 | wr = sgt->sgl; | |
472 | for (i = 0; i < sgt->orig_nents; ++i) { | |
473 | sg_set_page(wr, sg_page(rd), rd->length, rd->offset); | |
474 | rd = sg_next(rd); | |
475 | wr = sg_next(wr); | |
476 | } | |
477 | ||
478 | attach->dma_dir = DMA_NONE; | |
479 | dbuf_attach->priv = attach; | |
480 | ||
481 | return 0; | |
482 | } | |
483 | ||
484 | static void vb2_dma_sg_dmabuf_ops_detach(struct dma_buf *dbuf, | |
485 | struct dma_buf_attachment *db_attach) | |
486 | { | |
487 | struct vb2_dma_sg_attachment *attach = db_attach->priv; | |
488 | struct sg_table *sgt; | |
489 | ||
490 | if (!attach) | |
491 | return; | |
492 | ||
493 | sgt = &attach->sgt; | |
494 | ||
495 | /* release the scatterlist cache */ | |
496 | if (attach->dma_dir != DMA_NONE) | |
497 | dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, | |
498 | attach->dma_dir); | |
499 | sg_free_table(sgt); | |
500 | kfree(attach); | |
501 | db_attach->priv = NULL; | |
502 | } | |
503 | ||
504 | static struct sg_table *vb2_dma_sg_dmabuf_ops_map( | |
505 | struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir) | |
506 | { | |
507 | struct vb2_dma_sg_attachment *attach = db_attach->priv; | |
508 | /* stealing dmabuf mutex to serialize map/unmap operations */ | |
509 | struct mutex *lock = &db_attach->dmabuf->lock; | |
510 | struct sg_table *sgt; | |
511 | int ret; | |
512 | ||
513 | mutex_lock(lock); | |
514 | ||
515 | sgt = &attach->sgt; | |
516 | /* return previously mapped sg table */ | |
517 | if (attach->dma_dir == dma_dir) { | |
518 | mutex_unlock(lock); | |
519 | return sgt; | |
520 | } | |
521 | ||
522 | /* release any previous cache */ | |
523 | if (attach->dma_dir != DMA_NONE) { | |
524 | dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, | |
525 | attach->dma_dir); | |
526 | attach->dma_dir = DMA_NONE; | |
527 | } | |
528 | ||
529 | /* mapping to the client with new direction */ | |
530 | ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dma_dir); | |
531 | if (ret <= 0) { | |
532 | pr_err("failed to map scatterlist\n"); | |
533 | mutex_unlock(lock); | |
534 | return ERR_PTR(-EIO); | |
535 | } | |
536 | ||
537 | attach->dma_dir = dma_dir; | |
538 | ||
539 | mutex_unlock(lock); | |
540 | ||
541 | return sgt; | |
542 | } | |
543 | ||
544 | static void vb2_dma_sg_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, | |
545 | struct sg_table *sgt, enum dma_data_direction dma_dir) | |
546 | { | |
547 | /* nothing to be done here */ | |
548 | } | |
549 | ||
550 | static void vb2_dma_sg_dmabuf_ops_release(struct dma_buf *dbuf) | |
551 | { | |
552 | /* drop reference obtained in vb2_dma_sg_get_dmabuf */ | |
553 | vb2_dma_sg_put(dbuf->priv); | |
554 | } | |
555 | ||
556 | static void *vb2_dma_sg_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum) | |
557 | { | |
558 | struct vb2_dma_sg_buf *buf = dbuf->priv; | |
559 | ||
560 | return buf->vaddr ? buf->vaddr + pgnum * PAGE_SIZE : NULL; | |
561 | } | |
562 | ||
563 | static void *vb2_dma_sg_dmabuf_ops_vmap(struct dma_buf *dbuf) | |
564 | { | |
565 | struct vb2_dma_sg_buf *buf = dbuf->priv; | |
566 | ||
567 | return vb2_dma_sg_vaddr(buf); | |
568 | } | |
569 | ||
570 | static int vb2_dma_sg_dmabuf_ops_mmap(struct dma_buf *dbuf, | |
571 | struct vm_area_struct *vma) | |
572 | { | |
573 | return vb2_dma_sg_mmap(dbuf->priv, vma); | |
574 | } | |
575 | ||
576 | static struct dma_buf_ops vb2_dma_sg_dmabuf_ops = { | |
577 | .attach = vb2_dma_sg_dmabuf_ops_attach, | |
578 | .detach = vb2_dma_sg_dmabuf_ops_detach, | |
579 | .map_dma_buf = vb2_dma_sg_dmabuf_ops_map, | |
580 | .unmap_dma_buf = vb2_dma_sg_dmabuf_ops_unmap, | |
581 | .kmap = vb2_dma_sg_dmabuf_ops_kmap, | |
582 | .kmap_atomic = vb2_dma_sg_dmabuf_ops_kmap, | |
583 | .vmap = vb2_dma_sg_dmabuf_ops_vmap, | |
584 | .mmap = vb2_dma_sg_dmabuf_ops_mmap, | |
585 | .release = vb2_dma_sg_dmabuf_ops_release, | |
586 | }; | |
587 | ||
588 | static struct dma_buf *vb2_dma_sg_get_dmabuf(void *buf_priv, unsigned long flags) | |
589 | { | |
590 | struct vb2_dma_sg_buf *buf = buf_priv; | |
591 | struct dma_buf *dbuf; | |
d8fbe341 SS |
592 | DEFINE_DMA_BUF_EXPORT_INFO(exp_info); |
593 | ||
594 | exp_info.ops = &vb2_dma_sg_dmabuf_ops; | |
595 | exp_info.size = buf->size; | |
596 | exp_info.flags = flags; | |
597 | exp_info.priv = buf; | |
041c7b6a HV |
598 | |
599 | if (WARN_ON(!buf->dma_sgt)) | |
600 | return NULL; | |
601 | ||
d8fbe341 | 602 | dbuf = dma_buf_export(&exp_info); |
041c7b6a HV |
603 | if (IS_ERR(dbuf)) |
604 | return NULL; | |
605 | ||
606 | /* dmabuf keeps reference to vb2 buffer */ | |
607 | atomic_inc(&buf->refcount); | |
608 | ||
609 | return dbuf; | |
610 | } | |
611 | ||
e078b79d HV |
612 | /*********************************************/ |
613 | /* callbacks for DMABUF buffers */ | |
614 | /*********************************************/ | |
615 | ||
616 | static int vb2_dma_sg_map_dmabuf(void *mem_priv) | |
617 | { | |
618 | struct vb2_dma_sg_buf *buf = mem_priv; | |
619 | struct sg_table *sgt; | |
620 | ||
621 | if (WARN_ON(!buf->db_attach)) { | |
622 | pr_err("trying to pin a non attached buffer\n"); | |
623 | return -EINVAL; | |
624 | } | |
625 | ||
626 | if (WARN_ON(buf->dma_sgt)) { | |
627 | pr_err("dmabuf buffer is already pinned\n"); | |
628 | return 0; | |
629 | } | |
630 | ||
631 | /* get the associated scatterlist for this buffer */ | |
632 | sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir); | |
633 | if (IS_ERR(sgt)) { | |
634 | pr_err("Error getting dmabuf scatterlist\n"); | |
635 | return -EINVAL; | |
636 | } | |
637 | ||
638 | buf->dma_sgt = sgt; | |
639 | buf->vaddr = NULL; | |
640 | ||
641 | return 0; | |
642 | } | |
643 | ||
644 | static void vb2_dma_sg_unmap_dmabuf(void *mem_priv) | |
645 | { | |
646 | struct vb2_dma_sg_buf *buf = mem_priv; | |
647 | struct sg_table *sgt = buf->dma_sgt; | |
648 | ||
649 | if (WARN_ON(!buf->db_attach)) { | |
650 | pr_err("trying to unpin a not attached buffer\n"); | |
651 | return; | |
652 | } | |
653 | ||
654 | if (WARN_ON(!sgt)) { | |
655 | pr_err("dmabuf buffer is already unpinned\n"); | |
656 | return; | |
657 | } | |
658 | ||
659 | if (buf->vaddr) { | |
660 | dma_buf_vunmap(buf->db_attach->dmabuf, buf->vaddr); | |
661 | buf->vaddr = NULL; | |
662 | } | |
663 | dma_buf_unmap_attachment(buf->db_attach, sgt, buf->dma_dir); | |
664 | ||
665 | buf->dma_sgt = NULL; | |
666 | } | |
667 | ||
668 | static void vb2_dma_sg_detach_dmabuf(void *mem_priv) | |
669 | { | |
670 | struct vb2_dma_sg_buf *buf = mem_priv; | |
671 | ||
672 | /* if vb2 works correctly you should never detach mapped buffer */ | |
673 | if (WARN_ON(buf->dma_sgt)) | |
674 | vb2_dma_sg_unmap_dmabuf(buf); | |
675 | ||
676 | /* detach this attachment */ | |
677 | dma_buf_detach(buf->db_attach->dmabuf, buf->db_attach); | |
678 | kfree(buf); | |
679 | } | |
680 | ||
681 | static void *vb2_dma_sg_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, | |
682 | unsigned long size, enum dma_data_direction dma_dir) | |
683 | { | |
684 | struct vb2_dma_sg_conf *conf = alloc_ctx; | |
685 | struct vb2_dma_sg_buf *buf; | |
686 | struct dma_buf_attachment *dba; | |
687 | ||
688 | if (dbuf->size < size) | |
689 | return ERR_PTR(-EFAULT); | |
690 | ||
691 | buf = kzalloc(sizeof(*buf), GFP_KERNEL); | |
692 | if (!buf) | |
693 | return ERR_PTR(-ENOMEM); | |
694 | ||
695 | buf->dev = conf->dev; | |
696 | /* create attachment for the dmabuf with the user device */ | |
697 | dba = dma_buf_attach(dbuf, buf->dev); | |
698 | if (IS_ERR(dba)) { | |
699 | pr_err("failed to attach dmabuf\n"); | |
700 | kfree(buf); | |
701 | return dba; | |
702 | } | |
703 | ||
704 | buf->dma_dir = dma_dir; | |
705 | buf->size = size; | |
706 | buf->db_attach = dba; | |
707 | ||
708 | return buf; | |
709 | } | |
710 | ||
5ba3f757 AP |
711 | static void *vb2_dma_sg_cookie(void *buf_priv) |
712 | { | |
713 | struct vb2_dma_sg_buf *buf = buf_priv; | |
714 | ||
e078b79d | 715 | return buf->dma_sgt; |
5ba3f757 AP |
716 | } |
717 | ||
718 | const struct vb2_mem_ops vb2_dma_sg_memops = { | |
719 | .alloc = vb2_dma_sg_alloc, | |
720 | .put = vb2_dma_sg_put, | |
721 | .get_userptr = vb2_dma_sg_get_userptr, | |
722 | .put_userptr = vb2_dma_sg_put_userptr, | |
d790b7ed HV |
723 | .prepare = vb2_dma_sg_prepare, |
724 | .finish = vb2_dma_sg_finish, | |
5ba3f757 AP |
725 | .vaddr = vb2_dma_sg_vaddr, |
726 | .mmap = vb2_dma_sg_mmap, | |
727 | .num_users = vb2_dma_sg_num_users, | |
041c7b6a | 728 | .get_dmabuf = vb2_dma_sg_get_dmabuf, |
e078b79d HV |
729 | .map_dmabuf = vb2_dma_sg_map_dmabuf, |
730 | .unmap_dmabuf = vb2_dma_sg_unmap_dmabuf, | |
731 | .attach_dmabuf = vb2_dma_sg_attach_dmabuf, | |
732 | .detach_dmabuf = vb2_dma_sg_detach_dmabuf, | |
5ba3f757 AP |
733 | .cookie = vb2_dma_sg_cookie, |
734 | }; | |
735 | EXPORT_SYMBOL_GPL(vb2_dma_sg_memops); | |
736 | ||
0c3a14c1 HV |
737 | void *vb2_dma_sg_init_ctx(struct device *dev) |
738 | { | |
739 | struct vb2_dma_sg_conf *conf; | |
740 | ||
741 | conf = kzalloc(sizeof(*conf), GFP_KERNEL); | |
742 | if (!conf) | |
743 | return ERR_PTR(-ENOMEM); | |
744 | ||
745 | conf->dev = dev; | |
746 | ||
747 | return conf; | |
748 | } | |
749 | EXPORT_SYMBOL_GPL(vb2_dma_sg_init_ctx); | |
750 | ||
751 | void vb2_dma_sg_cleanup_ctx(void *alloc_ctx) | |
752 | { | |
753 | if (!IS_ERR_OR_NULL(alloc_ctx)) | |
754 | kfree(alloc_ctx); | |
755 | } | |
756 | EXPORT_SYMBOL_GPL(vb2_dma_sg_cleanup_ctx); | |
757 | ||
5ba3f757 AP |
758 | MODULE_DESCRIPTION("dma scatter/gather memory handling routines for videobuf2"); |
759 | MODULE_AUTHOR("Andrzej Pietrasiewicz"); | |
760 | MODULE_LICENSE("GPL"); |