1 /*
2  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
3  *                   Takashi Iwai <tiwai@suse.de>
4  *
5  *  Generic memory allocators
6  *
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; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  *
22  */
23 
24 #include <linux/module.h>
25 #include <linux/proc_fs.h>
26 #include <linux/init.h>
27 #include <linux/pci.h>
28 #include <linux/slab.h>
29 #include <linux/mm.h>
30 #include <linux/seq_file.h>
31 #include <asm/uaccess.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/moduleparam.h>
34 #include <linux/mutex.h>
35 #include <sound/memalloc.h>
36 
37 
38 MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>");
39 MODULE_DESCRIPTION("Memory allocator for ALSA system.");
40 MODULE_LICENSE("GPL");
41 
42 
43 /*
44  */
45 
46 static DEFINE_MUTEX(list_mutex);
47 static LIST_HEAD(mem_list_head);
48 
49 /* buffer preservation list */
50 struct snd_mem_list {
51 	struct snd_dma_buffer buffer;
52 	unsigned int id;
53 	struct list_head list;
54 };
55 
56 /* id for pre-allocated buffers */
57 #define SNDRV_DMA_DEVICE_UNUSED (unsigned int)-1
58 
59 /*
60  *
61  *  Generic memory allocators
62  *
63  */
64 
65 static long snd_allocated_pages; /* holding the number of allocated pages */
66 
inc_snd_pages(int order)67 static inline void inc_snd_pages(int order)
68 {
69 	snd_allocated_pages += 1 << order;
70 }
71 
dec_snd_pages(int order)72 static inline void dec_snd_pages(int order)
73 {
74 	snd_allocated_pages -= 1 << order;
75 }
76 
77 /**
78  * snd_malloc_pages - allocate pages with the given size
79  * @size: the size to allocate in bytes
80  * @gfp_flags: the allocation conditions, GFP_XXX
81  *
82  * Allocates the physically contiguous pages with the given size.
83  *
84  * Returns the pointer of the buffer, or NULL if no enoguh memory.
85  */
snd_malloc_pages(size_t size,gfp_t gfp_flags)86 void *snd_malloc_pages(size_t size, gfp_t gfp_flags)
87 {
88 	int pg;
89 	void *res;
90 
91 	if (WARN_ON(!size))
92 		return NULL;
93 	if (WARN_ON(!gfp_flags))
94 		return NULL;
95 	gfp_flags |= __GFP_COMP;	/* compound page lets parts be mapped */
96 	pg = get_order(size);
97 	if ((res = (void *) __get_free_pages(gfp_flags, pg)) != NULL)
98 		inc_snd_pages(pg);
99 	return res;
100 }
101 
102 /**
103  * snd_free_pages - release the pages
104  * @ptr: the buffer pointer to release
105  * @size: the allocated buffer size
106  *
107  * Releases the buffer allocated via snd_malloc_pages().
108  */
snd_free_pages(void * ptr,size_t size)109 void snd_free_pages(void *ptr, size_t size)
110 {
111 	int pg;
112 
113 	if (ptr == NULL)
114 		return;
115 	pg = get_order(size);
116 	dec_snd_pages(pg);
117 	free_pages((unsigned long) ptr, pg);
118 }
119 
120 /*
121  *
122  *  Bus-specific memory allocators
123  *
124  */
125 
126 #ifdef CONFIG_HAS_DMA
127 /* allocate the coherent DMA pages */
snd_malloc_dev_pages(struct device * dev,size_t size,dma_addr_t * dma)128 static void *snd_malloc_dev_pages(struct device *dev, size_t size, dma_addr_t *dma)
129 {
130 	int pg;
131 	void *res;
132 	gfp_t gfp_flags;
133 
134 	if (WARN_ON(!dma))
135 		return NULL;
136 	pg = get_order(size);
137 	gfp_flags = GFP_KERNEL
138 		| __GFP_COMP	/* compound page lets parts be mapped */
139 		| __GFP_NORETRY /* don't trigger OOM-killer */
140 		| __GFP_NOWARN; /* no stack trace print - this call is non-critical */
141 	res = dma_alloc_coherent(dev, PAGE_SIZE << pg, dma, gfp_flags);
142 	if (res != NULL)
143 		inc_snd_pages(pg);
144 
145 	return res;
146 }
147 
148 /* free the coherent DMA pages */
snd_free_dev_pages(struct device * dev,size_t size,void * ptr,dma_addr_t dma)149 static void snd_free_dev_pages(struct device *dev, size_t size, void *ptr,
150 			       dma_addr_t dma)
151 {
152 	int pg;
153 
154 	if (ptr == NULL)
155 		return;
156 	pg = get_order(size);
157 	dec_snd_pages(pg);
158 	dma_free_coherent(dev, PAGE_SIZE << pg, ptr, dma);
159 }
160 #endif /* CONFIG_HAS_DMA */
161 
162 /*
163  *
164  *  ALSA generic memory management
165  *
166  */
167 
168 
169 /**
170  * snd_dma_alloc_pages - allocate the buffer area according to the given type
171  * @type: the DMA buffer type
172  * @device: the device pointer
173  * @size: the buffer size to allocate
174  * @dmab: buffer allocation record to store the allocated data
175  *
176  * Calls the memory-allocator function for the corresponding
177  * buffer type.
178  *
179  * Returns zero if the buffer with the given size is allocated successfuly,
180  * other a negative value at error.
181  */
snd_dma_alloc_pages(int type,struct device * device,size_t size,struct snd_dma_buffer * dmab)182 int snd_dma_alloc_pages(int type, struct device *device, size_t size,
183 			struct snd_dma_buffer *dmab)
184 {
185 	if (WARN_ON(!size))
186 		return -ENXIO;
187 	if (WARN_ON(!dmab))
188 		return -ENXIO;
189 
190 	dmab->dev.type = type;
191 	dmab->dev.dev = device;
192 	dmab->bytes = 0;
193 	switch (type) {
194 	case SNDRV_DMA_TYPE_CONTINUOUS:
195 		dmab->area = snd_malloc_pages(size,
196 					(__force gfp_t)(unsigned long)device);
197 		dmab->addr = 0;
198 		break;
199 #ifdef CONFIG_HAS_DMA
200 	case SNDRV_DMA_TYPE_DEV:
201 		dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
202 		break;
203 #endif
204 #ifdef CONFIG_SND_DMA_SGBUF
205 	case SNDRV_DMA_TYPE_DEV_SG:
206 		snd_malloc_sgbuf_pages(device, size, dmab, NULL);
207 		break;
208 #endif
209 	default:
210 		printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
211 		dmab->area = NULL;
212 		dmab->addr = 0;
213 		return -ENXIO;
214 	}
215 	if (! dmab->area)
216 		return -ENOMEM;
217 	dmab->bytes = size;
218 	return 0;
219 }
220 
221 /**
222  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
223  * @type: the DMA buffer type
224  * @device: the device pointer
225  * @size: the buffer size to allocate
226  * @dmab: buffer allocation record to store the allocated data
227  *
228  * Calls the memory-allocator function for the corresponding
229  * buffer type.  When no space is left, this function reduces the size and
230  * tries to allocate again.  The size actually allocated is stored in
231  * res_size argument.
232  *
233  * Returns zero if the buffer with the given size is allocated successfuly,
234  * other a negative value at error.
235  */
snd_dma_alloc_pages_fallback(int type,struct device * device,size_t size,struct snd_dma_buffer * dmab)236 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
237 				 struct snd_dma_buffer *dmab)
238 {
239 	int err;
240 
241 	while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
242 		size_t aligned_size;
243 		if (err != -ENOMEM)
244 			return err;
245 		if (size <= PAGE_SIZE)
246 			return -ENOMEM;
247 		aligned_size = PAGE_SIZE << get_order(size);
248 		if (size != aligned_size)
249 			size = aligned_size;
250 		else
251 			size >>= 1;
252 	}
253 	if (! dmab->area)
254 		return -ENOMEM;
255 	return 0;
256 }
257 
258 
259 /**
260  * snd_dma_free_pages - release the allocated buffer
261  * @dmab: the buffer allocation record to release
262  *
263  * Releases the allocated buffer via snd_dma_alloc_pages().
264  */
snd_dma_free_pages(struct snd_dma_buffer * dmab)265 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
266 {
267 	switch (dmab->dev.type) {
268 	case SNDRV_DMA_TYPE_CONTINUOUS:
269 		snd_free_pages(dmab->area, dmab->bytes);
270 		break;
271 #ifdef CONFIG_HAS_DMA
272 	case SNDRV_DMA_TYPE_DEV:
273 		snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
274 		break;
275 #endif
276 #ifdef CONFIG_SND_DMA_SGBUF
277 	case SNDRV_DMA_TYPE_DEV_SG:
278 		snd_free_sgbuf_pages(dmab);
279 		break;
280 #endif
281 	default:
282 		printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
283 	}
284 }
285 
286 
287 /**
288  * snd_dma_get_reserved - get the reserved buffer for the given device
289  * @dmab: the buffer allocation record to store
290  * @id: the buffer id
291  *
292  * Looks for the reserved-buffer list and re-uses if the same buffer
293  * is found in the list.  When the buffer is found, it's removed from the free list.
294  *
295  * Returns the size of buffer if the buffer is found, or zero if not found.
296  */
snd_dma_get_reserved_buf(struct snd_dma_buffer * dmab,unsigned int id)297 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
298 {
299 	struct snd_mem_list *mem;
300 
301 	if (WARN_ON(!dmab))
302 		return 0;
303 
304 	mutex_lock(&list_mutex);
305 	list_for_each_entry(mem, &mem_list_head, list) {
306 		if (mem->id == id &&
307 		    (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
308 		     ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
309 			struct device *dev = dmab->dev.dev;
310 			list_del(&mem->list);
311 			*dmab = mem->buffer;
312 			if (dmab->dev.dev == NULL)
313 				dmab->dev.dev = dev;
314 			kfree(mem);
315 			mutex_unlock(&list_mutex);
316 			return dmab->bytes;
317 		}
318 	}
319 	mutex_unlock(&list_mutex);
320 	return 0;
321 }
322 
323 /**
324  * snd_dma_reserve_buf - reserve the buffer
325  * @dmab: the buffer to reserve
326  * @id: the buffer id
327  *
328  * Reserves the given buffer as a reserved buffer.
329  *
330  * Returns zero if successful, or a negative code at error.
331  */
snd_dma_reserve_buf(struct snd_dma_buffer * dmab,unsigned int id)332 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
333 {
334 	struct snd_mem_list *mem;
335 
336 	if (WARN_ON(!dmab))
337 		return -EINVAL;
338 	mem = kmalloc(sizeof(*mem), GFP_KERNEL);
339 	if (! mem)
340 		return -ENOMEM;
341 	mutex_lock(&list_mutex);
342 	mem->buffer = *dmab;
343 	mem->id = id;
344 	list_add_tail(&mem->list, &mem_list_head);
345 	mutex_unlock(&list_mutex);
346 	return 0;
347 }
348 
349 /*
350  * purge all reserved buffers
351  */
free_all_reserved_pages(void)352 static void free_all_reserved_pages(void)
353 {
354 	struct list_head *p;
355 	struct snd_mem_list *mem;
356 
357 	mutex_lock(&list_mutex);
358 	while (! list_empty(&mem_list_head)) {
359 		p = mem_list_head.next;
360 		mem = list_entry(p, struct snd_mem_list, list);
361 		list_del(p);
362 		snd_dma_free_pages(&mem->buffer);
363 		kfree(mem);
364 	}
365 	mutex_unlock(&list_mutex);
366 }
367 
368 
369 #ifdef CONFIG_PROC_FS
370 /*
371  * proc file interface
372  */
373 #define SND_MEM_PROC_FILE	"driver/snd-page-alloc"
374 static struct proc_dir_entry *snd_mem_proc;
375 
snd_mem_proc_read(struct seq_file * seq,void * offset)376 static int snd_mem_proc_read(struct seq_file *seq, void *offset)
377 {
378 	long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
379 	struct snd_mem_list *mem;
380 	int devno;
381 	static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG" };
382 
383 	mutex_lock(&list_mutex);
384 	seq_printf(seq, "pages  : %li bytes (%li pages per %likB)\n",
385 		   pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
386 	devno = 0;
387 	list_for_each_entry(mem, &mem_list_head, list) {
388 		devno++;
389 		seq_printf(seq, "buffer %d : ID %08x : type %s\n",
390 			   devno, mem->id, types[mem->buffer.dev.type]);
391 		seq_printf(seq, "  addr = 0x%lx, size = %d bytes\n",
392 			   (unsigned long)mem->buffer.addr,
393 			   (int)mem->buffer.bytes);
394 	}
395 	mutex_unlock(&list_mutex);
396 	return 0;
397 }
398 
snd_mem_proc_open(struct inode * inode,struct file * file)399 static int snd_mem_proc_open(struct inode *inode, struct file *file)
400 {
401 	return single_open(file, snd_mem_proc_read, NULL);
402 }
403 
404 /* FIXME: for pci only - other bus? */
405 #ifdef CONFIG_PCI
406 #define gettoken(bufp) strsep(bufp, " \t\n")
407 
snd_mem_proc_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)408 static ssize_t snd_mem_proc_write(struct file *file, const char __user * buffer,
409 				  size_t count, loff_t * ppos)
410 {
411 	char buf[128];
412 	char *token, *p;
413 
414 	if (count > sizeof(buf) - 1)
415 		return -EINVAL;
416 	if (copy_from_user(buf, buffer, count))
417 		return -EFAULT;
418 	buf[count] = '\0';
419 
420 	p = buf;
421 	token = gettoken(&p);
422 	if (! token || *token == '#')
423 		return count;
424 	if (strcmp(token, "add") == 0) {
425 		char *endp;
426 		int vendor, device, size, buffers;
427 		long mask;
428 		int i, alloced;
429 		struct pci_dev *pci;
430 
431 		if ((token = gettoken(&p)) == NULL ||
432 		    (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
433 		    (token = gettoken(&p)) == NULL ||
434 		    (device = simple_strtol(token, NULL, 0)) <= 0 ||
435 		    (token = gettoken(&p)) == NULL ||
436 		    (mask = simple_strtol(token, NULL, 0)) < 0 ||
437 		    (token = gettoken(&p)) == NULL ||
438 		    (size = memparse(token, &endp)) < 64*1024 ||
439 		    size > 16*1024*1024 /* too big */ ||
440 		    (token = gettoken(&p)) == NULL ||
441 		    (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
442 		    buffers > 4) {
443 			printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
444 			return count;
445 		}
446 		vendor &= 0xffff;
447 		device &= 0xffff;
448 
449 		alloced = 0;
450 		pci = NULL;
451 		while ((pci = pci_get_device(vendor, device, pci)) != NULL) {
452 			if (mask > 0 && mask < 0xffffffff) {
453 				if (pci_set_dma_mask(pci, mask) < 0 ||
454 				    pci_set_consistent_dma_mask(pci, mask) < 0) {
455 					printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
456 					pci_dev_put(pci);
457 					return count;
458 				}
459 			}
460 			for (i = 0; i < buffers; i++) {
461 				struct snd_dma_buffer dmab;
462 				memset(&dmab, 0, sizeof(dmab));
463 				if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
464 							size, &dmab) < 0) {
465 					printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
466 					pci_dev_put(pci);
467 					return count;
468 				}
469 				snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
470 			}
471 			alloced++;
472 		}
473 		if (! alloced) {
474 			for (i = 0; i < buffers; i++) {
475 				struct snd_dma_buffer dmab;
476 				memset(&dmab, 0, sizeof(dmab));
477 				/* FIXME: We can allocate only in ZONE_DMA
478 				 * without a device pointer!
479 				 */
480 				if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
481 							size, &dmab) < 0) {
482 					printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
483 					break;
484 				}
485 				snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
486 			}
487 		}
488 	} else if (strcmp(token, "erase") == 0)
489 		/* FIXME: need for releasing each buffer chunk? */
490 		free_all_reserved_pages();
491 	else
492 		printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
493 	return count;
494 }
495 #endif /* CONFIG_PCI */
496 
497 static const struct file_operations snd_mem_proc_fops = {
498 	.owner		= THIS_MODULE,
499 	.open		= snd_mem_proc_open,
500 	.read		= seq_read,
501 #ifdef CONFIG_PCI
502 	.write		= snd_mem_proc_write,
503 #endif
504 	.llseek		= seq_lseek,
505 	.release	= single_release,
506 };
507 
508 #endif /* CONFIG_PROC_FS */
509 
510 /*
511  * module entry
512  */
513 
snd_mem_init(void)514 static int __init snd_mem_init(void)
515 {
516 #ifdef CONFIG_PROC_FS
517 	snd_mem_proc = proc_create(SND_MEM_PROC_FILE, 0644, NULL,
518 				   &snd_mem_proc_fops);
519 #endif
520 	return 0;
521 }
522 
snd_mem_exit(void)523 static void __exit snd_mem_exit(void)
524 {
525 	remove_proc_entry(SND_MEM_PROC_FILE, NULL);
526 	free_all_reserved_pages();
527 	if (snd_allocated_pages > 0)
528 		printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
529 }
530 
531 
532 module_init(snd_mem_init)
533 module_exit(snd_mem_exit)
534 
535 
536 /*
537  * exports
538  */
539 EXPORT_SYMBOL(snd_dma_alloc_pages);
540 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
541 EXPORT_SYMBOL(snd_dma_free_pages);
542 
543 EXPORT_SYMBOL(snd_dma_get_reserved_buf);
544 EXPORT_SYMBOL(snd_dma_reserve_buf);
545 
546 EXPORT_SYMBOL(snd_malloc_pages);
547 EXPORT_SYMBOL(snd_free_pages);
548