2 * videobuf2-vmalloc.c - vmalloc memory allocator for videobuf2
4 * Copyright (C) 2010 Samsung Electronics
6 * Author: Pawel Osciak <pawel@osciak.com>
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.
14 #include <linux/module.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/vmalloc.h>
20 #include <media/videobuf2-core.h>
21 #include <media/videobuf2-vmalloc.h>
22 #include <media/videobuf2-memops.h>
24 struct vb2_vmalloc_buf
{
27 struct vm_area_struct
*vma
;
28 enum dma_data_direction dma_dir
;
32 struct vb2_vmarea_handler handler
;
36 static void vb2_vmalloc_put(void *buf_priv
);
38 static void *vb2_vmalloc_alloc(void *alloc_ctx
, unsigned long size
,
39 enum dma_data_direction dma_dir
, gfp_t gfp_flags
)
41 struct vb2_vmalloc_buf
*buf
;
43 buf
= kzalloc(sizeof(*buf
), GFP_KERNEL
| gfp_flags
);
48 buf
->vaddr
= vmalloc_user(buf
->size
);
49 buf
->dma_dir
= dma_dir
;
50 buf
->handler
.refcount
= &buf
->refcount
;
51 buf
->handler
.put
= vb2_vmalloc_put
;
52 buf
->handler
.arg
= buf
;
55 pr_debug("vmalloc of size %ld failed\n", buf
->size
);
60 atomic_inc(&buf
->refcount
);
64 static void vb2_vmalloc_put(void *buf_priv
)
66 struct vb2_vmalloc_buf
*buf
= buf_priv
;
68 if (atomic_dec_and_test(&buf
->refcount
)) {
74 static void *vb2_vmalloc_get_userptr(void *alloc_ctx
, unsigned long vaddr
,
76 enum dma_data_direction dma_dir
)
78 struct vb2_vmalloc_buf
*buf
;
79 unsigned long first
, last
;
81 struct vm_area_struct
*vma
;
84 buf
= kzalloc(sizeof(*buf
), GFP_KERNEL
);
88 buf
->dma_dir
= dma_dir
;
89 offset
= vaddr
& ~PAGE_MASK
;
92 down_read(¤t
->mm
->mmap_sem
);
93 vma
= find_vma(current
->mm
, vaddr
);
94 if (vma
&& (vma
->vm_flags
& VM_PFNMAP
) && (vma
->vm_pgoff
)) {
95 if (vb2_get_contig_userptr(vaddr
, size
, &vma
, &physp
))
96 goto fail_pages_array_alloc
;
98 buf
->vaddr
= (__force
void *)ioremap_nocache(physp
, size
);
100 goto fail_pages_array_alloc
;
102 first
= vaddr
>> PAGE_SHIFT
;
103 last
= (vaddr
+ size
- 1) >> PAGE_SHIFT
;
104 buf
->n_pages
= last
- first
+ 1;
105 buf
->pages
= kzalloc(buf
->n_pages
* sizeof(struct page
*),
108 goto fail_pages_array_alloc
;
110 /* current->mm->mmap_sem is taken by videobuf2 core */
111 n_pages
= get_user_pages(current
, current
->mm
,
112 vaddr
& PAGE_MASK
, buf
->n_pages
,
113 dma_dir
== DMA_FROM_DEVICE
,
116 if (n_pages
!= buf
->n_pages
)
117 goto fail_get_user_pages
;
119 buf
->vaddr
= vm_map_ram(buf
->pages
, buf
->n_pages
, -1,
122 goto fail_get_user_pages
;
124 up_read(¤t
->mm
->mmap_sem
);
126 buf
->vaddr
+= offset
;
130 pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages
,
132 while (--n_pages
>= 0)
133 put_page(buf
->pages
[n_pages
]);
136 fail_pages_array_alloc
:
137 up_read(¤t
->mm
->mmap_sem
);
143 static void vb2_vmalloc_put_userptr(void *buf_priv
)
145 struct vb2_vmalloc_buf
*buf
= buf_priv
;
146 unsigned long vaddr
= (unsigned long)buf
->vaddr
& PAGE_MASK
;
149 down_read(¤t
->mm
->mmap_sem
);
152 vm_unmap_ram((void *)vaddr
, buf
->n_pages
);
153 for (i
= 0; i
< buf
->n_pages
; ++i
) {
154 if (buf
->dma_dir
== DMA_FROM_DEVICE
)
155 set_page_dirty_lock(buf
->pages
[i
]);
156 put_page(buf
->pages
[i
]);
160 vb2_put_vma(buf
->vma
);
161 iounmap((__force
void __iomem
*)buf
->vaddr
);
163 up_read(¤t
->mm
->mmap_sem
);
167 static void *vb2_vmalloc_vaddr(void *buf_priv
)
169 struct vb2_vmalloc_buf
*buf
= buf_priv
;
172 pr_err("Address of an unallocated plane requested "
173 "or cannot map user pointer\n");
180 static unsigned int vb2_vmalloc_num_users(void *buf_priv
)
182 struct vb2_vmalloc_buf
*buf
= buf_priv
;
183 return atomic_read(&buf
->refcount
);
186 static int vb2_vmalloc_mmap(void *buf_priv
, struct vm_area_struct
*vma
)
188 struct vb2_vmalloc_buf
*buf
= buf_priv
;
192 pr_err("No memory to map\n");
196 ret
= remap_vmalloc_range(vma
, buf
->vaddr
, 0);
198 pr_err("Remapping vmalloc memory, error: %d\n", ret
);
203 * Make sure that vm_areas for 2 buffers won't be merged together
205 vma
->vm_flags
|= VM_DONTEXPAND
;
208 * Use common vm_area operations to track buffer refcount.
210 vma
->vm_private_data
= &buf
->handler
;
211 vma
->vm_ops
= &vb2_common_vm_ops
;
213 vma
->vm_ops
->open(vma
);
218 #ifdef CONFIG_HAS_DMA
219 /*********************************************/
220 /* DMABUF ops for exporters */
221 /*********************************************/
223 struct vb2_vmalloc_attachment
{
225 enum dma_data_direction dma_dir
;
228 static int vb2_vmalloc_dmabuf_ops_attach(struct dma_buf
*dbuf
, struct device
*dev
,
229 struct dma_buf_attachment
*dbuf_attach
)
231 struct vb2_vmalloc_attachment
*attach
;
232 struct vb2_vmalloc_buf
*buf
= dbuf
->priv
;
233 int num_pages
= PAGE_ALIGN(buf
->size
) / PAGE_SIZE
;
234 struct sg_table
*sgt
;
235 struct scatterlist
*sg
;
236 void *vaddr
= buf
->vaddr
;
240 attach
= kzalloc(sizeof(*attach
), GFP_KERNEL
);
245 ret
= sg_alloc_table(sgt
, num_pages
, GFP_KERNEL
);
250 for_each_sg(sgt
->sgl
, sg
, sgt
->nents
, i
) {
251 struct page
*page
= vmalloc_to_page(vaddr
);
258 sg_set_page(sg
, page
, PAGE_SIZE
, 0);
262 attach
->dma_dir
= DMA_NONE
;
263 dbuf_attach
->priv
= attach
;
267 static void vb2_vmalloc_dmabuf_ops_detach(struct dma_buf
*dbuf
,
268 struct dma_buf_attachment
*db_attach
)
270 struct vb2_vmalloc_attachment
*attach
= db_attach
->priv
;
271 struct sg_table
*sgt
;
278 /* release the scatterlist cache */
279 if (attach
->dma_dir
!= DMA_NONE
)
280 dma_unmap_sg(db_attach
->dev
, sgt
->sgl
, sgt
->orig_nents
,
284 db_attach
->priv
= NULL
;
287 static struct sg_table
*vb2_vmalloc_dmabuf_ops_map(
288 struct dma_buf_attachment
*db_attach
, enum dma_data_direction dma_dir
)
290 struct vb2_vmalloc_attachment
*attach
= db_attach
->priv
;
291 /* stealing dmabuf mutex to serialize map/unmap operations */
292 struct mutex
*lock
= &db_attach
->dmabuf
->lock
;
293 struct sg_table
*sgt
;
298 /* return previously mapped sg table */
299 if (attach
->dma_dir
== dma_dir
) {
304 /* release any previous cache */
305 if (attach
->dma_dir
!= DMA_NONE
) {
306 dma_unmap_sg(db_attach
->dev
, sgt
->sgl
, sgt
->orig_nents
,
308 attach
->dma_dir
= DMA_NONE
;
311 /* mapping to the client with new direction */
312 sgt
->nents
= dma_map_sg(db_attach
->dev
, sgt
->sgl
, sgt
->orig_nents
,
315 pr_err("failed to map scatterlist\n");
317 return ERR_PTR(-EIO
);
320 attach
->dma_dir
= dma_dir
;
327 static void vb2_vmalloc_dmabuf_ops_unmap(struct dma_buf_attachment
*db_attach
,
328 struct sg_table
*sgt
, enum dma_data_direction dma_dir
)
330 /* nothing to be done here */
333 static void vb2_vmalloc_dmabuf_ops_release(struct dma_buf
*dbuf
)
335 /* drop reference obtained in vb2_vmalloc_get_dmabuf */
336 vb2_vmalloc_put(dbuf
->priv
);
339 static void *vb2_vmalloc_dmabuf_ops_kmap(struct dma_buf
*dbuf
, unsigned long pgnum
)
341 struct vb2_vmalloc_buf
*buf
= dbuf
->priv
;
343 return buf
->vaddr
+ pgnum
* PAGE_SIZE
;
346 static void *vb2_vmalloc_dmabuf_ops_vmap(struct dma_buf
*dbuf
)
348 struct vb2_vmalloc_buf
*buf
= dbuf
->priv
;
353 static int vb2_vmalloc_dmabuf_ops_mmap(struct dma_buf
*dbuf
,
354 struct vm_area_struct
*vma
)
356 return vb2_vmalloc_mmap(dbuf
->priv
, vma
);
359 static struct dma_buf_ops vb2_vmalloc_dmabuf_ops
= {
360 .attach
= vb2_vmalloc_dmabuf_ops_attach
,
361 .detach
= vb2_vmalloc_dmabuf_ops_detach
,
362 .map_dma_buf
= vb2_vmalloc_dmabuf_ops_map
,
363 .unmap_dma_buf
= vb2_vmalloc_dmabuf_ops_unmap
,
364 .kmap
= vb2_vmalloc_dmabuf_ops_kmap
,
365 .kmap_atomic
= vb2_vmalloc_dmabuf_ops_kmap
,
366 .vmap
= vb2_vmalloc_dmabuf_ops_vmap
,
367 .mmap
= vb2_vmalloc_dmabuf_ops_mmap
,
368 .release
= vb2_vmalloc_dmabuf_ops_release
,
371 static struct dma_buf
*vb2_vmalloc_get_dmabuf(void *buf_priv
, unsigned long flags
)
373 struct vb2_vmalloc_buf
*buf
= buf_priv
;
374 struct dma_buf
*dbuf
;
375 DEFINE_DMA_BUF_EXPORT_INFO(exp_info
);
377 exp_info
.ops
= &vb2_vmalloc_dmabuf_ops
;
378 exp_info
.size
= buf
->size
;
379 exp_info
.flags
= flags
;
382 if (WARN_ON(!buf
->vaddr
))
385 dbuf
= dma_buf_export(&exp_info
);
389 /* dmabuf keeps reference to vb2 buffer */
390 atomic_inc(&buf
->refcount
);
394 #endif /* CONFIG_HAS_DMA */
397 /*********************************************/
398 /* callbacks for DMABUF buffers */
399 /*********************************************/
401 static int vb2_vmalloc_map_dmabuf(void *mem_priv
)
403 struct vb2_vmalloc_buf
*buf
= mem_priv
;
405 buf
->vaddr
= dma_buf_vmap(buf
->dbuf
);
407 return buf
->vaddr
? 0 : -EFAULT
;
410 static void vb2_vmalloc_unmap_dmabuf(void *mem_priv
)
412 struct vb2_vmalloc_buf
*buf
= mem_priv
;
414 dma_buf_vunmap(buf
->dbuf
, buf
->vaddr
);
418 static void vb2_vmalloc_detach_dmabuf(void *mem_priv
)
420 struct vb2_vmalloc_buf
*buf
= mem_priv
;
423 dma_buf_vunmap(buf
->dbuf
, buf
->vaddr
);
428 static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx
, struct dma_buf
*dbuf
,
429 unsigned long size
, enum dma_data_direction dma_dir
)
431 struct vb2_vmalloc_buf
*buf
;
433 if (dbuf
->size
< size
)
434 return ERR_PTR(-EFAULT
);
436 buf
= kzalloc(sizeof(*buf
), GFP_KERNEL
);
438 return ERR_PTR(-ENOMEM
);
441 buf
->dma_dir
= dma_dir
;
448 const struct vb2_mem_ops vb2_vmalloc_memops
= {
449 .alloc
= vb2_vmalloc_alloc
,
450 .put
= vb2_vmalloc_put
,
451 .get_userptr
= vb2_vmalloc_get_userptr
,
452 .put_userptr
= vb2_vmalloc_put_userptr
,
453 #ifdef CONFIG_HAS_DMA
454 .get_dmabuf
= vb2_vmalloc_get_dmabuf
,
456 .map_dmabuf
= vb2_vmalloc_map_dmabuf
,
457 .unmap_dmabuf
= vb2_vmalloc_unmap_dmabuf
,
458 .attach_dmabuf
= vb2_vmalloc_attach_dmabuf
,
459 .detach_dmabuf
= vb2_vmalloc_detach_dmabuf
,
460 .vaddr
= vb2_vmalloc_vaddr
,
461 .mmap
= vb2_vmalloc_mmap
,
462 .num_users
= vb2_vmalloc_num_users
,
464 EXPORT_SYMBOL_GPL(vb2_vmalloc_memops
);
466 MODULE_DESCRIPTION("vmalloc memory handling routines for videobuf2");
467 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>");
468 MODULE_LICENSE("GPL");