xref: /openbmc/linux/sound/core/memalloc.c (revision a09d2831)
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 
67 static inline void inc_snd_pages(int order)
68 {
69 	snd_allocated_pages += 1 << order;
70 }
71 
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  */
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  */
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 */
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 */
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  */
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, (unsigned long)device);
196 		dmab->addr = 0;
197 		break;
198 #ifdef CONFIG_HAS_DMA
199 	case SNDRV_DMA_TYPE_DEV:
200 		dmab->area = snd_malloc_dev_pages(device, size, &dmab->addr);
201 		break;
202 #endif
203 #ifdef CONFIG_SND_DMA_SGBUF
204 	case SNDRV_DMA_TYPE_DEV_SG:
205 		snd_malloc_sgbuf_pages(device, size, dmab, NULL);
206 		break;
207 #endif
208 	default:
209 		printk(KERN_ERR "snd-malloc: invalid device type %d\n", type);
210 		dmab->area = NULL;
211 		dmab->addr = 0;
212 		return -ENXIO;
213 	}
214 	if (! dmab->area)
215 		return -ENOMEM;
216 	dmab->bytes = size;
217 	return 0;
218 }
219 
220 /**
221  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
222  * @type: the DMA buffer type
223  * @device: the device pointer
224  * @size: the buffer size to allocate
225  * @dmab: buffer allocation record to store the allocated data
226  *
227  * Calls the memory-allocator function for the corresponding
228  * buffer type.  When no space is left, this function reduces the size and
229  * tries to allocate again.  The size actually allocated is stored in
230  * res_size argument.
231  *
232  * Returns zero if the buffer with the given size is allocated successfuly,
233  * other a negative value at error.
234  */
235 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
236 				 struct snd_dma_buffer *dmab)
237 {
238 	int err;
239 
240 	while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
241 		size_t aligned_size;
242 		if (err != -ENOMEM)
243 			return err;
244 		if (size <= PAGE_SIZE)
245 			return -ENOMEM;
246 		aligned_size = PAGE_SIZE << get_order(size);
247 		if (size != aligned_size)
248 			size = aligned_size;
249 		else
250 			size >>= 1;
251 	}
252 	if (! dmab->area)
253 		return -ENOMEM;
254 	return 0;
255 }
256 
257 
258 /**
259  * snd_dma_free_pages - release the allocated buffer
260  * @dmab: the buffer allocation record to release
261  *
262  * Releases the allocated buffer via snd_dma_alloc_pages().
263  */
264 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
265 {
266 	switch (dmab->dev.type) {
267 	case SNDRV_DMA_TYPE_CONTINUOUS:
268 		snd_free_pages(dmab->area, dmab->bytes);
269 		break;
270 #ifdef CONFIG_HAS_DMA
271 	case SNDRV_DMA_TYPE_DEV:
272 		snd_free_dev_pages(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
273 		break;
274 #endif
275 #ifdef CONFIG_SND_DMA_SGBUF
276 	case SNDRV_DMA_TYPE_DEV_SG:
277 		snd_free_sgbuf_pages(dmab);
278 		break;
279 #endif
280 	default:
281 		printk(KERN_ERR "snd-malloc: invalid device type %d\n", dmab->dev.type);
282 	}
283 }
284 
285 
286 /**
287  * snd_dma_get_reserved - get the reserved buffer for the given device
288  * @dmab: the buffer allocation record to store
289  * @id: the buffer id
290  *
291  * Looks for the reserved-buffer list and re-uses if the same buffer
292  * is found in the list.  When the buffer is found, it's removed from the free list.
293  *
294  * Returns the size of buffer if the buffer is found, or zero if not found.
295  */
296 size_t snd_dma_get_reserved_buf(struct snd_dma_buffer *dmab, unsigned int id)
297 {
298 	struct snd_mem_list *mem;
299 
300 	if (WARN_ON(!dmab))
301 		return 0;
302 
303 	mutex_lock(&list_mutex);
304 	list_for_each_entry(mem, &mem_list_head, list) {
305 		if (mem->id == id &&
306 		    (mem->buffer.dev.dev == NULL || dmab->dev.dev == NULL ||
307 		     ! memcmp(&mem->buffer.dev, &dmab->dev, sizeof(dmab->dev)))) {
308 			struct device *dev = dmab->dev.dev;
309 			list_del(&mem->list);
310 			*dmab = mem->buffer;
311 			if (dmab->dev.dev == NULL)
312 				dmab->dev.dev = dev;
313 			kfree(mem);
314 			mutex_unlock(&list_mutex);
315 			return dmab->bytes;
316 		}
317 	}
318 	mutex_unlock(&list_mutex);
319 	return 0;
320 }
321 
322 /**
323  * snd_dma_reserve_buf - reserve the buffer
324  * @dmab: the buffer to reserve
325  * @id: the buffer id
326  *
327  * Reserves the given buffer as a reserved buffer.
328  *
329  * Returns zero if successful, or a negative code at error.
330  */
331 int snd_dma_reserve_buf(struct snd_dma_buffer *dmab, unsigned int id)
332 {
333 	struct snd_mem_list *mem;
334 
335 	if (WARN_ON(!dmab))
336 		return -EINVAL;
337 	mem = kmalloc(sizeof(*mem), GFP_KERNEL);
338 	if (! mem)
339 		return -ENOMEM;
340 	mutex_lock(&list_mutex);
341 	mem->buffer = *dmab;
342 	mem->id = id;
343 	list_add_tail(&mem->list, &mem_list_head);
344 	mutex_unlock(&list_mutex);
345 	return 0;
346 }
347 
348 /*
349  * purge all reserved buffers
350  */
351 static void free_all_reserved_pages(void)
352 {
353 	struct list_head *p;
354 	struct snd_mem_list *mem;
355 
356 	mutex_lock(&list_mutex);
357 	while (! list_empty(&mem_list_head)) {
358 		p = mem_list_head.next;
359 		mem = list_entry(p, struct snd_mem_list, list);
360 		list_del(p);
361 		snd_dma_free_pages(&mem->buffer);
362 		kfree(mem);
363 	}
364 	mutex_unlock(&list_mutex);
365 }
366 
367 
368 #ifdef CONFIG_PROC_FS
369 /*
370  * proc file interface
371  */
372 #define SND_MEM_PROC_FILE	"driver/snd-page-alloc"
373 static struct proc_dir_entry *snd_mem_proc;
374 
375 static int snd_mem_proc_read(struct seq_file *seq, void *offset)
376 {
377 	long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
378 	struct snd_mem_list *mem;
379 	int devno;
380 	static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG" };
381 
382 	mutex_lock(&list_mutex);
383 	seq_printf(seq, "pages  : %li bytes (%li pages per %likB)\n",
384 		   pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
385 	devno = 0;
386 	list_for_each_entry(mem, &mem_list_head, list) {
387 		devno++;
388 		seq_printf(seq, "buffer %d : ID %08x : type %s\n",
389 			   devno, mem->id, types[mem->buffer.dev.type]);
390 		seq_printf(seq, "  addr = 0x%lx, size = %d bytes\n",
391 			   (unsigned long)mem->buffer.addr,
392 			   (int)mem->buffer.bytes);
393 	}
394 	mutex_unlock(&list_mutex);
395 	return 0;
396 }
397 
398 static int snd_mem_proc_open(struct inode *inode, struct file *file)
399 {
400 	return single_open(file, snd_mem_proc_read, NULL);
401 }
402 
403 /* FIXME: for pci only - other bus? */
404 #ifdef CONFIG_PCI
405 #define gettoken(bufp) strsep(bufp, " \t\n")
406 
407 static ssize_t snd_mem_proc_write(struct file *file, const char __user * buffer,
408 				  size_t count, loff_t * ppos)
409 {
410 	char buf[128];
411 	char *token, *p;
412 
413 	if (count > sizeof(buf) - 1)
414 		return -EINVAL;
415 	if (copy_from_user(buf, buffer, count))
416 		return -EFAULT;
417 	buf[count] = '\0';
418 
419 	p = buf;
420 	token = gettoken(&p);
421 	if (! token || *token == '#')
422 		return count;
423 	if (strcmp(token, "add") == 0) {
424 		char *endp;
425 		int vendor, device, size, buffers;
426 		long mask;
427 		int i, alloced;
428 		struct pci_dev *pci;
429 
430 		if ((token = gettoken(&p)) == NULL ||
431 		    (vendor = simple_strtol(token, NULL, 0)) <= 0 ||
432 		    (token = gettoken(&p)) == NULL ||
433 		    (device = simple_strtol(token, NULL, 0)) <= 0 ||
434 		    (token = gettoken(&p)) == NULL ||
435 		    (mask = simple_strtol(token, NULL, 0)) < 0 ||
436 		    (token = gettoken(&p)) == NULL ||
437 		    (size = memparse(token, &endp)) < 64*1024 ||
438 		    size > 16*1024*1024 /* too big */ ||
439 		    (token = gettoken(&p)) == NULL ||
440 		    (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
441 		    buffers > 4) {
442 			printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
443 			return count;
444 		}
445 		vendor &= 0xffff;
446 		device &= 0xffff;
447 
448 		alloced = 0;
449 		pci = NULL;
450 		while ((pci = pci_get_device(vendor, device, pci)) != NULL) {
451 			if (mask > 0 && mask < 0xffffffff) {
452 				if (pci_set_dma_mask(pci, mask) < 0 ||
453 				    pci_set_consistent_dma_mask(pci, mask) < 0) {
454 					printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
455 					pci_dev_put(pci);
456 					return count;
457 				}
458 			}
459 			for (i = 0; i < buffers; i++) {
460 				struct snd_dma_buffer dmab;
461 				memset(&dmab, 0, sizeof(dmab));
462 				if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(pci),
463 							size, &dmab) < 0) {
464 					printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
465 					pci_dev_put(pci);
466 					return count;
467 				}
468 				snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
469 			}
470 			alloced++;
471 		}
472 		if (! alloced) {
473 			for (i = 0; i < buffers; i++) {
474 				struct snd_dma_buffer dmab;
475 				memset(&dmab, 0, sizeof(dmab));
476 				/* FIXME: We can allocate only in ZONE_DMA
477 				 * without a device pointer!
478 				 */
479 				if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, NULL,
480 							size, &dmab) < 0) {
481 					printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
482 					break;
483 				}
484 				snd_dma_reserve_buf(&dmab, (unsigned int)((vendor << 16) | device));
485 			}
486 		}
487 	} else if (strcmp(token, "erase") == 0)
488 		/* FIXME: need for releasing each buffer chunk? */
489 		free_all_reserved_pages();
490 	else
491 		printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
492 	return count;
493 }
494 #endif /* CONFIG_PCI */
495 
496 static const struct file_operations snd_mem_proc_fops = {
497 	.owner		= THIS_MODULE,
498 	.open		= snd_mem_proc_open,
499 	.read		= seq_read,
500 #ifdef CONFIG_PCI
501 	.write		= snd_mem_proc_write,
502 #endif
503 	.llseek		= seq_lseek,
504 	.release	= single_release,
505 };
506 
507 #endif /* CONFIG_PROC_FS */
508 
509 /*
510  * module entry
511  */
512 
513 static int __init snd_mem_init(void)
514 {
515 #ifdef CONFIG_PROC_FS
516 	snd_mem_proc = proc_create(SND_MEM_PROC_FILE, 0644, NULL,
517 				   &snd_mem_proc_fops);
518 #endif
519 	return 0;
520 }
521 
522 static void __exit snd_mem_exit(void)
523 {
524 	remove_proc_entry(SND_MEM_PROC_FILE, NULL);
525 	free_all_reserved_pages();
526 	if (snd_allocated_pages > 0)
527 		printk(KERN_ERR "snd-malloc: Memory leak?  pages not freed = %li\n", snd_allocated_pages);
528 }
529 
530 
531 module_init(snd_mem_init)
532 module_exit(snd_mem_exit)
533 
534 
535 /*
536  * exports
537  */
538 EXPORT_SYMBOL(snd_dma_alloc_pages);
539 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
540 EXPORT_SYMBOL(snd_dma_free_pages);
541 
542 EXPORT_SYMBOL(snd_dma_get_reserved_buf);
543 EXPORT_SYMBOL(snd_dma_reserve_buf);
544 
545 EXPORT_SYMBOL(snd_malloc_pages);
546 EXPORT_SYMBOL(snd_free_pages);
547