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87b9ad07 MCC |
1 | /* |
2 | * helper functions for vmalloc video4linux capture buffers | |
3 | * | |
4 | * The functions expect the hardware being able to scatter gatter | |
5 | * (i.e. the buffers are not linear in physical memory, but fragmented | |
6 | * into PAGE_SIZE chunks). They also assume the driver does not need | |
7 | * to touch the video data. | |
8 | * | |
9 | * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org> | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2 | |
14 | */ | |
15 | ||
16 | #include <linux/init.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/moduleparam.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/interrupt.h> | |
21 | ||
22 | #include <linux/pci.h> | |
23 | #include <linux/vmalloc.h> | |
24 | #include <linux/pagemap.h> | |
25 | #include <asm/page.h> | |
26 | #include <asm/pgtable.h> | |
27 | ||
28 | #include <media/videobuf-vmalloc.h> | |
29 | ||
30 | #define MAGIC_DMABUF 0x17760309 | |
31 | #define MAGIC_VMAL_MEM 0x18221223 | |
32 | ||
33 | #define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \ | |
34 | { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); } | |
35 | ||
36 | static int debug = 0; | |
37 | module_param(debug, int, 0644); | |
38 | ||
39 | MODULE_DESCRIPTION("helper module to manage video4linux vmalloc buffers"); | |
40 | MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>"); | |
41 | MODULE_LICENSE("GPL"); | |
42 | ||
43 | #define dprintk(level, fmt, arg...) if (debug >= level) \ | |
44 | printk(KERN_DEBUG "vbuf-sg: " fmt , ## arg) | |
45 | ||
46 | ||
47 | /***************************************************************************/ | |
48 | ||
49 | static void | |
50 | videobuf_vm_open(struct vm_area_struct *vma) | |
51 | { | |
52 | struct videobuf_mapping *map = vma->vm_private_data; | |
53 | ||
54 | dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map, | |
55 | map->count,vma->vm_start,vma->vm_end); | |
56 | ||
57 | map->count++; | |
58 | } | |
59 | ||
60 | static void | |
61 | videobuf_vm_close(struct vm_area_struct *vma) | |
62 | { | |
63 | struct videobuf_mapping *map = vma->vm_private_data; | |
64 | struct videobuf_queue *q = map->q; | |
65 | struct videbuf_vmalloc_memory *mem; | |
66 | int i; | |
67 | ||
68 | dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map, | |
69 | map->count,vma->vm_start,vma->vm_end); | |
70 | ||
71 | map->count--; | |
72 | if (0 == map->count) { | |
73 | dprintk(1,"munmap %p q=%p\n",map,q); | |
74 | mutex_lock(&q->lock); | |
75 | for (i = 0; i < VIDEO_MAX_FRAME; i++) { | |
76 | if (NULL == q->bufs[i]) | |
77 | continue; | |
78 | mem=q->bufs[i]->priv; | |
79 | ||
80 | if (!mem) | |
81 | continue; | |
82 | ||
83 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
84 | ||
85 | if (mem->map != map) | |
86 | continue; | |
123f8ef6 MCC |
87 | |
88 | q->ops->buf_release(q,q->bufs[i]); | |
89 | ||
87b9ad07 MCC |
90 | mem->map = NULL; |
91 | q->bufs[i]->baddr = 0; | |
87b9ad07 MCC |
92 | } |
93 | mutex_unlock(&q->lock); | |
94 | kfree(map); | |
95 | } | |
96 | return; | |
97 | } | |
98 | ||
99 | static struct vm_operations_struct videobuf_vm_ops = | |
100 | { | |
101 | .open = videobuf_vm_open, | |
102 | .close = videobuf_vm_close, | |
103 | }; | |
104 | ||
105 | /* --------------------------------------------------------------------- | |
106 | * vmalloc handlers for the generic methods | |
107 | */ | |
108 | ||
109 | /* Allocated area consists on 3 parts: | |
110 | struct video_buffer | |
111 | struct <driver>_buffer (cx88_buffer, saa7134_buf, ...) | |
112 | struct videobuf_pci_sg_memory | |
113 | */ | |
114 | ||
115 | static void *__videobuf_alloc(size_t size) | |
116 | { | |
117 | struct videbuf_vmalloc_memory *mem; | |
118 | struct videobuf_buffer *vb; | |
119 | ||
120 | vb = kzalloc(size+sizeof(*mem),GFP_KERNEL); | |
121 | ||
122 | mem = vb->priv = ((char *)vb)+size; | |
123 | mem->magic=MAGIC_VMAL_MEM; | |
124 | ||
125 | dprintk(1,"%s: allocated at %p(%ld+%ld) & %p(%ld)\n", | |
126 | __FUNCTION__,vb,(long)sizeof(*vb),(long)size-sizeof(*vb), | |
127 | mem,(long)sizeof(*mem)); | |
128 | ||
129 | return vb; | |
130 | } | |
131 | ||
132 | static int __videobuf_iolock (struct videobuf_queue* q, | |
133 | struct videobuf_buffer *vb, | |
134 | struct v4l2_framebuffer *fbuf) | |
135 | { | |
136 | int pages; | |
137 | ||
138 | struct videbuf_vmalloc_memory *mem=vb->priv; | |
139 | ||
140 | ||
141 | BUG_ON(!mem); | |
142 | ||
143 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
144 | ||
87b9ad07 MCC |
145 | pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT; |
146 | ||
147 | /* Currently, doesn't support V4L2_MEMORY_OVERLAY */ | |
148 | if ((vb->memory != V4L2_MEMORY_MMAP) && | |
149 | (vb->memory != V4L2_MEMORY_USERPTR) ) { | |
150 | printk(KERN_ERR "Method currently unsupported.\n"); | |
151 | return -EINVAL; | |
152 | } | |
153 | ||
154 | /* FIXME: should be tested with kernel mmap mem */ | |
155 | mem->vmalloc=vmalloc_user (PAGE_ALIGN(vb->size)); | |
156 | if (NULL == mem->vmalloc) { | |
e78dcf55 | 157 | printk(KERN_ERR "vmalloc (%d pages) failed\n",pages); |
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158 | return -ENOMEM; |
159 | } | |
160 | ||
161 | dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n", | |
162 | (unsigned long)mem->vmalloc, | |
163 | pages << PAGE_SHIFT); | |
164 | ||
165 | /* It seems that some kernel versions need to do remap *after* | |
166 | the mmap() call | |
167 | */ | |
168 | if (mem->vma) { | |
169 | int retval=remap_vmalloc_range(mem->vma, mem->vmalloc,0); | |
170 | kfree(mem->vma); | |
171 | mem->vma=NULL; | |
172 | if (retval<0) { | |
173 | dprintk(1,"mmap app bug: remap_vmalloc_range area %p error %d\n", | |
174 | mem->vmalloc,retval); | |
175 | return retval; | |
176 | } | |
177 | } | |
178 | ||
179 | return 0; | |
180 | } | |
181 | ||
182 | static int __videobuf_sync(struct videobuf_queue *q, | |
183 | struct videobuf_buffer *buf) | |
184 | { | |
185 | return 0; | |
186 | } | |
187 | ||
188 | static int __videobuf_mmap_free(struct videobuf_queue *q) | |
189 | { | |
190 | unsigned int i; | |
191 | ||
192 | for (i = 0; i < VIDEO_MAX_FRAME; i++) { | |
193 | if (q->bufs[i]) { | |
194 | struct videbuf_vmalloc_memory *mem=q->bufs[i]->priv; | |
195 | if (mem && mem->map) | |
196 | return -EBUSY; | |
197 | } | |
198 | } | |
199 | ||
200 | return 0; | |
201 | } | |
202 | ||
203 | static int __videobuf_mmap_mapper(struct videobuf_queue *q, | |
204 | struct vm_area_struct *vma) | |
205 | { | |
206 | struct videbuf_vmalloc_memory *mem; | |
207 | struct videobuf_mapping *map; | |
208 | unsigned int first; | |
209 | int retval; | |
210 | unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; | |
211 | ||
212 | if (! (vma->vm_flags & VM_WRITE) || ! (vma->vm_flags & VM_SHARED)) | |
213 | return -EINVAL; | |
214 | ||
215 | /* look for first buffer to map */ | |
216 | for (first = 0; first < VIDEO_MAX_FRAME; first++) { | |
217 | if (NULL == q->bufs[first]) | |
218 | continue; | |
219 | ||
220 | if (V4L2_MEMORY_MMAP != q->bufs[first]->memory) | |
221 | continue; | |
222 | if (q->bufs[first]->boff == offset) | |
223 | break; | |
224 | } | |
225 | if (VIDEO_MAX_FRAME == first) { | |
226 | dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n", | |
227 | (vma->vm_pgoff << PAGE_SHIFT)); | |
228 | return -EINVAL; | |
229 | } | |
230 | mem=q->bufs[first]->priv; | |
231 | BUG_ON (!mem); | |
232 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
233 | ||
234 | /* create mapping + update buffer list */ | |
235 | map = mem->map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL); | |
236 | if (NULL == map) | |
237 | return -ENOMEM; | |
238 | ||
239 | map->start = vma->vm_start; | |
240 | map->end = vma->vm_end; | |
241 | map->q = q; | |
242 | ||
243 | q->bufs[first]->baddr = vma->vm_start; | |
244 | ||
245 | vma->vm_ops = &videobuf_vm_ops; | |
246 | vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED; | |
247 | vma->vm_private_data = map; | |
248 | ||
249 | /* Try to remap memory */ | |
250 | retval=remap_vmalloc_range(vma, mem->vmalloc,0); | |
251 | if (retval<0) { | |
252 | dprintk(1,"mmap: postponing remap_vmalloc_range\n"); | |
253 | mem->vma=kmalloc(sizeof(*vma),GFP_KERNEL); | |
254 | if (!mem->vma) { | |
255 | kfree(map); | |
256 | mem->map=NULL; | |
257 | return -ENOMEM; | |
258 | } | |
259 | memcpy(mem->vma,vma,sizeof(*vma)); | |
260 | } | |
261 | ||
262 | dprintk(1,"mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n", | |
263 | map,q,vma->vm_start,vma->vm_end, | |
264 | (long int) q->bufs[first]->bsize, | |
265 | vma->vm_pgoff,first); | |
266 | ||
267 | videobuf_vm_open(vma); | |
268 | ||
269 | return (0); | |
270 | } | |
271 | ||
272 | static int __videobuf_is_mmapped (struct videobuf_buffer *buf) | |
273 | { | |
274 | struct videbuf_vmalloc_memory *mem=buf->priv; | |
275 | BUG_ON (!mem); | |
276 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
277 | ||
278 | return (mem->map)?1:0; | |
279 | } | |
280 | ||
281 | static int __videobuf_copy_to_user ( struct videobuf_queue *q, | |
282 | char __user *data, size_t count, | |
283 | int nonblocking ) | |
284 | { | |
285 | struct videbuf_vmalloc_memory *mem=q->read_buf->priv; | |
286 | BUG_ON (!mem); | |
287 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
288 | ||
289 | BUG_ON (!mem->vmalloc); | |
290 | ||
291 | /* copy to userspace */ | |
292 | if (count > q->read_buf->size - q->read_off) | |
293 | count = q->read_buf->size - q->read_off; | |
294 | ||
295 | if (copy_to_user(data, mem->vmalloc+q->read_off, count)) | |
296 | return -EFAULT; | |
297 | ||
298 | return count; | |
299 | } | |
300 | ||
301 | static int __videobuf_copy_stream ( struct videobuf_queue *q, | |
302 | char __user *data, size_t count, size_t pos, | |
303 | int vbihack, int nonblocking ) | |
304 | { | |
305 | unsigned int *fc; | |
306 | struct videbuf_vmalloc_memory *mem=q->read_buf->priv; | |
307 | BUG_ON (!mem); | |
308 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
309 | ||
310 | if (vbihack) { | |
311 | /* dirty, undocumented hack -- pass the frame counter | |
312 | * within the last four bytes of each vbi data block. | |
313 | * We need that one to maintain backward compatibility | |
314 | * to all vbi decoding software out there ... */ | |
315 | fc = (unsigned int*)mem->vmalloc; | |
316 | fc += (q->read_buf->size>>2) -1; | |
317 | *fc = q->read_buf->field_count >> 1; | |
318 | dprintk(1,"vbihack: %d\n",*fc); | |
319 | } | |
320 | ||
321 | /* copy stuff using the common method */ | |
322 | count = __videobuf_copy_to_user (q,data,count,nonblocking); | |
323 | ||
324 | if ( (count==-EFAULT) && (0 == pos) ) | |
325 | return -EFAULT; | |
326 | ||
327 | return count; | |
328 | } | |
329 | ||
330 | static struct videobuf_qtype_ops qops = { | |
331 | .magic = MAGIC_QTYPE_OPS, | |
332 | ||
333 | .alloc = __videobuf_alloc, | |
334 | .iolock = __videobuf_iolock, | |
335 | .sync = __videobuf_sync, | |
336 | .mmap_free = __videobuf_mmap_free, | |
337 | .mmap_mapper = __videobuf_mmap_mapper, | |
338 | .is_mmapped = __videobuf_is_mmapped, | |
339 | .copy_to_user = __videobuf_copy_to_user, | |
340 | .copy_stream = __videobuf_copy_stream, | |
341 | }; | |
342 | ||
343 | void videobuf_queue_vmalloc_init(struct videobuf_queue* q, | |
344 | struct videobuf_queue_ops *ops, | |
345 | void *dev, | |
346 | spinlock_t *irqlock, | |
347 | enum v4l2_buf_type type, | |
348 | enum v4l2_field field, | |
349 | unsigned int msize, | |
350 | void *priv) | |
351 | { | |
352 | videobuf_queue_init(q, ops, dev, irqlock, type, field, msize, priv); | |
353 | q->int_ops=&qops; | |
354 | } | |
355 | ||
356 | EXPORT_SYMBOL_GPL(videobuf_queue_vmalloc_init); | |
357 | ||
358 | void *videobuf_to_vmalloc (struct videobuf_buffer *buf) | |
359 | { | |
360 | struct videbuf_vmalloc_memory *mem=buf->priv; | |
361 | BUG_ON (!mem); | |
362 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
363 | ||
364 | return mem->vmalloc; | |
365 | } | |
366 | EXPORT_SYMBOL_GPL(videobuf_to_vmalloc); | |
367 | ||
368 | void videobuf_vmalloc_free (struct videobuf_buffer *buf) | |
369 | { | |
370 | struct videbuf_vmalloc_memory *mem=buf->priv; | |
371 | BUG_ON (!mem); | |
372 | ||
373 | MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM); | |
374 | ||
375 | vfree(mem->vmalloc); | |
c520a497 | 376 | mem->vmalloc=NULL; |
87b9ad07 MCC |
377 | |
378 | return; | |
379 | } | |
380 | EXPORT_SYMBOL_GPL(videobuf_vmalloc_free); | |
381 | ||
382 | /* | |
383 | * Local variables: | |
384 | * c-basic-offset: 8 | |
385 | * End: | |
386 | */ |