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  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
 38MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>, Jaroslav Kysela <perex@perex.cz>");
 39MODULE_DESCRIPTION("Memory allocator for ALSA system.");
 40MODULE_LICENSE("GPL");
 41
 42
 43/*
 44 */
 45
 46static DEFINE_MUTEX(list_mutex);
 47static LIST_HEAD(mem_list_head);
 48
 49/* buffer preservation list */
 50struct 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
 65static long snd_allocated_pages; /* holding the number of allocated pages */
 66
 67static inline void inc_snd_pages(int order)
 68{
 69	snd_allocated_pages += 1 << order;
 70}
 71
 72static 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 */
 86void *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 */
109void 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 */
128static 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 */
149static 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 successfully,
180 * other a negative value at error.
181 */
182int 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 successfully,
234 * other a negative value at error.
235 */
236int 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 */
265void 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 */
297size_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 */
332int 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 */
352static 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"
374static struct proc_dir_entry *snd_mem_proc;
375
376static 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
399static 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
408static 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
497static 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
514static 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
523static 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
532module_init(snd_mem_init)
533module_exit(snd_mem_exit)
534
535
536/*
537 * exports
538 */
539EXPORT_SYMBOL(snd_dma_alloc_pages);
540EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
541EXPORT_SYMBOL(snd_dma_free_pages);
542
543EXPORT_SYMBOL(snd_dma_get_reserved_buf);
544EXPORT_SYMBOL(snd_dma_reserve_buf);
545
546EXPORT_SYMBOL(snd_malloc_pages);
547EXPORT_SYMBOL(snd_free_pages);