xref: /openbmc/linux/sound/pci/emu10k1/memory.c (revision 1e5323bd)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4  *  Copyright (c) by Takashi Iwai <tiwai@suse.de>
5  *
6  *  EMU10K1 memory page allocation (PTB area)
7  */
8 
9 #include <linux/pci.h>
10 #include <linux/gfp.h>
11 #include <linux/time.h>
12 #include <linux/mutex.h>
13 #include <linux/export.h>
14 
15 #include <sound/core.h>
16 #include <sound/emu10k1.h>
17 
18 /* page arguments of these two macros are Emu page (4096 bytes), not like
19  * aligned pages in others
20  */
21 #define __set_ptb_entry(emu,page,addr) \
22 	(((__le32 *)(emu)->ptb_pages.area)[page] = \
23 	 cpu_to_le32(((addr) << (emu->address_mode)) | (page)))
24 #define __get_ptb_entry(emu, page) \
25 	(le32_to_cpu(((__le32 *)(emu)->ptb_pages.area)[page]))
26 
27 #define UNIT_PAGES		(PAGE_SIZE / EMUPAGESIZE)
28 #define MAX_ALIGN_PAGES0		(MAXPAGES0 / UNIT_PAGES)
29 #define MAX_ALIGN_PAGES1		(MAXPAGES1 / UNIT_PAGES)
30 /* get aligned page from offset address */
31 #define get_aligned_page(offset)	((offset) >> PAGE_SHIFT)
32 /* get offset address from aligned page */
33 #define aligned_page_offset(page)	((page) << PAGE_SHIFT)
34 
35 #if PAGE_SIZE == EMUPAGESIZE && !IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
36 /* fill PTB entrie(s) corresponding to page with addr */
37 #define set_ptb_entry(emu,page,addr)	__set_ptb_entry(emu,page,addr)
38 /* fill PTB entrie(s) corresponding to page with silence pointer */
39 #define set_silent_ptb(emu,page)	__set_ptb_entry(emu,page,emu->silent_page.addr)
40 #else
41 /* fill PTB entries -- we need to fill UNIT_PAGES entries */
set_ptb_entry(struct snd_emu10k1 * emu,int page,dma_addr_t addr)42 static inline void set_ptb_entry(struct snd_emu10k1 *emu, int page, dma_addr_t addr)
43 {
44 	int i;
45 	page *= UNIT_PAGES;
46 	for (i = 0; i < UNIT_PAGES; i++, page++) {
47 		__set_ptb_entry(emu, page, addr);
48 		dev_dbg(emu->card->dev, "mapped page %d to entry %.8x\n", page,
49 			(unsigned int)__get_ptb_entry(emu, page));
50 		addr += EMUPAGESIZE;
51 	}
52 }
set_silent_ptb(struct snd_emu10k1 * emu,int page)53 static inline void set_silent_ptb(struct snd_emu10k1 *emu, int page)
54 {
55 	int i;
56 	page *= UNIT_PAGES;
57 	for (i = 0; i < UNIT_PAGES; i++, page++) {
58 		/* do not increment ptr */
59 		__set_ptb_entry(emu, page, emu->silent_page.addr);
60 		dev_dbg(emu->card->dev, "mapped silent page %d to entry %.8x\n",
61 			page, (unsigned int)__get_ptb_entry(emu, page));
62 	}
63 }
64 #endif /* PAGE_SIZE */
65 
66 
67 /*
68  */
69 static int synth_alloc_pages(struct snd_emu10k1 *hw, struct snd_emu10k1_memblk *blk);
70 static int synth_free_pages(struct snd_emu10k1 *hw, struct snd_emu10k1_memblk *blk);
71 
72 #define get_emu10k1_memblk(l,member)	list_entry(l, struct snd_emu10k1_memblk, member)
73 
74 
75 /* initialize emu10k1 part */
emu10k1_memblk_init(struct snd_emu10k1_memblk * blk)76 static void emu10k1_memblk_init(struct snd_emu10k1_memblk *blk)
77 {
78 	blk->mapped_page = -1;
79 	INIT_LIST_HEAD(&blk->mapped_link);
80 	INIT_LIST_HEAD(&blk->mapped_order_link);
81 	blk->map_locked = 0;
82 
83 	blk->first_page = get_aligned_page(blk->mem.offset);
84 	blk->last_page = get_aligned_page(blk->mem.offset + blk->mem.size - 1);
85 	blk->pages = blk->last_page - blk->first_page + 1;
86 }
87 
88 /*
89  * search empty region on PTB with the given size
90  *
91  * if an empty region is found, return the page and store the next mapped block
92  * in nextp
93  * if not found, return a negative error code.
94  */
search_empty_map_area(struct snd_emu10k1 * emu,int npages,struct list_head ** nextp)95 static int search_empty_map_area(struct snd_emu10k1 *emu, int npages, struct list_head **nextp)
96 {
97 	int page = 1, found_page = -ENOMEM;
98 	int max_size = npages;
99 	int size;
100 	struct list_head *candidate = &emu->mapped_link_head;
101 	struct list_head *pos;
102 
103 	list_for_each (pos, &emu->mapped_link_head) {
104 		struct snd_emu10k1_memblk *blk = get_emu10k1_memblk(pos, mapped_link);
105 		if (blk->mapped_page < 0)
106 			continue;
107 		size = blk->mapped_page - page;
108 		if (size == npages) {
109 			*nextp = pos;
110 			return page;
111 		}
112 		else if (size > max_size) {
113 			/* we look for the maximum empty hole */
114 			max_size = size;
115 			candidate = pos;
116 			found_page = page;
117 		}
118 		page = blk->mapped_page + blk->pages;
119 	}
120 	size = (emu->address_mode ? MAX_ALIGN_PAGES1 : MAX_ALIGN_PAGES0) - page;
121 	if (size >= max_size) {
122 		*nextp = pos;
123 		return page;
124 	}
125 	*nextp = candidate;
126 	return found_page;
127 }
128 
129 /*
130  * map a memory block onto emu10k1's PTB
131  *
132  * call with memblk_lock held
133  */
map_memblk(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)134 static int map_memblk(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
135 {
136 	int page, pg;
137 	struct list_head *next;
138 
139 	page = search_empty_map_area(emu, blk->pages, &next);
140 	if (page < 0) /* not found */
141 		return page;
142 	if (page == 0) {
143 		dev_err(emu->card->dev, "trying to map zero (reserved) page\n");
144 		return -EINVAL;
145 	}
146 	/* insert this block in the proper position of mapped list */
147 	list_add_tail(&blk->mapped_link, next);
148 	/* append this as a newest block in order list */
149 	list_add_tail(&blk->mapped_order_link, &emu->mapped_order_link_head);
150 	blk->mapped_page = page;
151 	/* fill PTB */
152 	for (pg = blk->first_page; pg <= blk->last_page; pg++) {
153 		set_ptb_entry(emu, page, emu->page_addr_table[pg]);
154 		page++;
155 	}
156 	return 0;
157 }
158 
159 /*
160  * unmap the block
161  * return the size of resultant empty pages
162  *
163  * call with memblk_lock held
164  */
unmap_memblk(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)165 static int unmap_memblk(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
166 {
167 	int start_page, end_page, mpage, pg;
168 	struct list_head *p;
169 	struct snd_emu10k1_memblk *q;
170 
171 	/* calculate the expected size of empty region */
172 	p = blk->mapped_link.prev;
173 	if (p != &emu->mapped_link_head) {
174 		q = get_emu10k1_memblk(p, mapped_link);
175 		start_page = q->mapped_page + q->pages;
176 	} else {
177 		start_page = 1;
178 	}
179 	p = blk->mapped_link.next;
180 	if (p != &emu->mapped_link_head) {
181 		q = get_emu10k1_memblk(p, mapped_link);
182 		end_page = q->mapped_page;
183 	} else {
184 		end_page = (emu->address_mode ? MAX_ALIGN_PAGES1 : MAX_ALIGN_PAGES0);
185 	}
186 
187 	/* remove links */
188 	list_del(&blk->mapped_link);
189 	list_del(&blk->mapped_order_link);
190 	/* clear PTB */
191 	mpage = blk->mapped_page;
192 	for (pg = blk->first_page; pg <= blk->last_page; pg++) {
193 		set_silent_ptb(emu, mpage);
194 		mpage++;
195 	}
196 	blk->mapped_page = -1;
197 	return end_page - start_page; /* return the new empty size */
198 }
199 
200 /*
201  * search empty pages with the given size, and create a memory block
202  *
203  * unlike synth_alloc the memory block is aligned to the page start
204  */
205 static struct snd_emu10k1_memblk *
search_empty(struct snd_emu10k1 * emu,int size)206 search_empty(struct snd_emu10k1 *emu, int size)
207 {
208 	struct list_head *p;
209 	struct snd_emu10k1_memblk *blk;
210 	int page, psize;
211 
212 	psize = get_aligned_page(size + PAGE_SIZE -1);
213 	page = 0;
214 	list_for_each(p, &emu->memhdr->block) {
215 		blk = get_emu10k1_memblk(p, mem.list);
216 		if (page + psize <= blk->first_page)
217 			goto __found_pages;
218 		page = blk->last_page + 1;
219 	}
220 	if (page + psize > emu->max_cache_pages)
221 		return NULL;
222 
223 __found_pages:
224 	/* create a new memory block */
225 	blk = (struct snd_emu10k1_memblk *)__snd_util_memblk_new(emu->memhdr, psize << PAGE_SHIFT, p->prev);
226 	if (blk == NULL)
227 		return NULL;
228 	blk->mem.offset = aligned_page_offset(page); /* set aligned offset */
229 	emu10k1_memblk_init(blk);
230 	return blk;
231 }
232 
233 
234 /*
235  * check if the given pointer is valid for pages
236  */
is_valid_page(struct snd_emu10k1 * emu,dma_addr_t addr)237 static int is_valid_page(struct snd_emu10k1 *emu, dma_addr_t addr)
238 {
239 	if (addr & ~emu->dma_mask) {
240 		dev_err_ratelimited(emu->card->dev,
241 			"max memory size is 0x%lx (addr = 0x%lx)!!\n",
242 			emu->dma_mask, (unsigned long)addr);
243 		return 0;
244 	}
245 	if (addr & (EMUPAGESIZE-1)) {
246 		dev_err_ratelimited(emu->card->dev, "page is not aligned\n");
247 		return 0;
248 	}
249 	return 1;
250 }
251 
252 /*
253  * map the given memory block on PTB.
254  * if the block is already mapped, update the link order.
255  * if no empty pages are found, tries to release unused memory blocks
256  * and retry the mapping.
257  */
snd_emu10k1_memblk_map(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)258 int snd_emu10k1_memblk_map(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
259 {
260 	int err;
261 	int size;
262 	struct list_head *p, *nextp;
263 	struct snd_emu10k1_memblk *deleted;
264 	unsigned long flags;
265 
266 	spin_lock_irqsave(&emu->memblk_lock, flags);
267 	if (blk->mapped_page >= 0) {
268 		/* update order link */
269 		list_move_tail(&blk->mapped_order_link,
270 			       &emu->mapped_order_link_head);
271 		spin_unlock_irqrestore(&emu->memblk_lock, flags);
272 		return 0;
273 	}
274 	err = map_memblk(emu, blk);
275 	if (err < 0) {
276 		/* no enough page - try to unmap some blocks */
277 		/* starting from the oldest block */
278 		p = emu->mapped_order_link_head.next;
279 		for (; p != &emu->mapped_order_link_head; p = nextp) {
280 			nextp = p->next;
281 			deleted = get_emu10k1_memblk(p, mapped_order_link);
282 			if (deleted->map_locked)
283 				continue;
284 			size = unmap_memblk(emu, deleted);
285 			if (size >= blk->pages) {
286 				/* ok the empty region is enough large */
287 				err = map_memblk(emu, blk);
288 				break;
289 			}
290 		}
291 	}
292 	spin_unlock_irqrestore(&emu->memblk_lock, flags);
293 	return err;
294 }
295 
296 EXPORT_SYMBOL(snd_emu10k1_memblk_map);
297 
298 /*
299  * page allocation for DMA
300  */
301 struct snd_util_memblk *
snd_emu10k1_alloc_pages(struct snd_emu10k1 * emu,struct snd_pcm_substream * substream)302 snd_emu10k1_alloc_pages(struct snd_emu10k1 *emu, struct snd_pcm_substream *substream)
303 {
304 	struct snd_pcm_runtime *runtime = substream->runtime;
305 	struct snd_util_memhdr *hdr;
306 	struct snd_emu10k1_memblk *blk;
307 	int page, err, idx;
308 
309 	if (snd_BUG_ON(!emu))
310 		return NULL;
311 	if (snd_BUG_ON(runtime->dma_bytes <= 0 ||
312 		       runtime->dma_bytes >= (emu->address_mode ? MAXPAGES1 : MAXPAGES0) * EMUPAGESIZE))
313 		return NULL;
314 	hdr = emu->memhdr;
315 	if (snd_BUG_ON(!hdr))
316 		return NULL;
317 
318 	mutex_lock(&hdr->block_mutex);
319 	blk = search_empty(emu, runtime->dma_bytes);
320 	if (blk == NULL) {
321 		mutex_unlock(&hdr->block_mutex);
322 		return NULL;
323 	}
324 	/* fill buffer addresses but pointers are not stored so that
325 	 * snd_free_pci_page() is not called in synth_free()
326 	 */
327 	idx = 0;
328 	for (page = blk->first_page; page <= blk->last_page; page++, idx++) {
329 		unsigned long ofs = idx << PAGE_SHIFT;
330 		dma_addr_t addr;
331 		if (ofs >= runtime->dma_bytes)
332 			addr = emu->silent_page.addr;
333 		else
334 			addr = snd_pcm_sgbuf_get_addr(substream, ofs);
335 		if (! is_valid_page(emu, addr)) {
336 			dev_err_ratelimited(emu->card->dev,
337 				"emu: failure page = %d\n", idx);
338 			mutex_unlock(&hdr->block_mutex);
339 			return NULL;
340 		}
341 		emu->page_addr_table[page] = addr;
342 		emu->page_ptr_table[page] = NULL;
343 	}
344 
345 	/* set PTB entries */
346 	blk->map_locked = 1; /* do not unmap this block! */
347 	err = snd_emu10k1_memblk_map(emu, blk);
348 	if (err < 0) {
349 		__snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
350 		mutex_unlock(&hdr->block_mutex);
351 		return NULL;
352 	}
353 	mutex_unlock(&hdr->block_mutex);
354 	return (struct snd_util_memblk *)blk;
355 }
356 
357 
358 /*
359  * release DMA buffer from page table
360  */
snd_emu10k1_free_pages(struct snd_emu10k1 * emu,struct snd_util_memblk * blk)361 int snd_emu10k1_free_pages(struct snd_emu10k1 *emu, struct snd_util_memblk *blk)
362 {
363 	if (snd_BUG_ON(!emu || !blk))
364 		return -EINVAL;
365 	return snd_emu10k1_synth_free(emu, blk);
366 }
367 
368 /*
369  * allocate DMA pages, widening the allocation if necessary
370  *
371  * See the comment above snd_emu10k1_detect_iommu() in emu10k1_main.c why
372  * this might be needed.
373  *
374  * If you modify this function check whether __synth_free_pages() also needs
375  * changes.
376  */
snd_emu10k1_alloc_pages_maybe_wider(struct snd_emu10k1 * emu,size_t size,struct snd_dma_buffer * dmab)377 int snd_emu10k1_alloc_pages_maybe_wider(struct snd_emu10k1 *emu, size_t size,
378 					struct snd_dma_buffer *dmab)
379 {
380 	if (emu->iommu_workaround) {
381 		size_t npages = DIV_ROUND_UP(size, PAGE_SIZE);
382 		size_t size_real = npages * PAGE_SIZE;
383 
384 		/*
385 		 * The device has been observed to accesses up to 256 extra
386 		 * bytes, but use 1k to be safe.
387 		 */
388 		if (size_real < size + 1024)
389 			size += PAGE_SIZE;
390 	}
391 
392 	return snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
393 				   &emu->pci->dev, size, dmab);
394 }
395 
396 /*
397  * memory allocation using multiple pages (for synth)
398  * Unlike the DMA allocation above, non-contiguous pages are assined.
399  */
400 
401 /*
402  * allocate a synth sample area
403  */
404 struct snd_util_memblk *
snd_emu10k1_synth_alloc(struct snd_emu10k1 * hw,unsigned int size)405 snd_emu10k1_synth_alloc(struct snd_emu10k1 *hw, unsigned int size)
406 {
407 	struct snd_emu10k1_memblk *blk;
408 	struct snd_util_memhdr *hdr = hw->memhdr;
409 
410 	mutex_lock(&hdr->block_mutex);
411 	blk = (struct snd_emu10k1_memblk *)__snd_util_mem_alloc(hdr, size);
412 	if (blk == NULL) {
413 		mutex_unlock(&hdr->block_mutex);
414 		return NULL;
415 	}
416 	if (synth_alloc_pages(hw, blk)) {
417 		__snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
418 		mutex_unlock(&hdr->block_mutex);
419 		return NULL;
420 	}
421 	snd_emu10k1_memblk_map(hw, blk);
422 	mutex_unlock(&hdr->block_mutex);
423 	return (struct snd_util_memblk *)blk;
424 }
425 
426 EXPORT_SYMBOL(snd_emu10k1_synth_alloc);
427 
428 /*
429  * free a synth sample area
430  */
431 int
snd_emu10k1_synth_free(struct snd_emu10k1 * emu,struct snd_util_memblk * memblk)432 snd_emu10k1_synth_free(struct snd_emu10k1 *emu, struct snd_util_memblk *memblk)
433 {
434 	struct snd_util_memhdr *hdr = emu->memhdr;
435 	struct snd_emu10k1_memblk *blk = (struct snd_emu10k1_memblk *)memblk;
436 	unsigned long flags;
437 
438 	mutex_lock(&hdr->block_mutex);
439 	spin_lock_irqsave(&emu->memblk_lock, flags);
440 	if (blk->mapped_page >= 0)
441 		unmap_memblk(emu, blk);
442 	spin_unlock_irqrestore(&emu->memblk_lock, flags);
443 	synth_free_pages(emu, blk);
444 	 __snd_util_mem_free(hdr, memblk);
445 	mutex_unlock(&hdr->block_mutex);
446 	return 0;
447 }
448 
449 EXPORT_SYMBOL(snd_emu10k1_synth_free);
450 
451 /* check new allocation range */
get_single_page_range(struct snd_util_memhdr * hdr,struct snd_emu10k1_memblk * blk,int * first_page_ret,int * last_page_ret)452 static void get_single_page_range(struct snd_util_memhdr *hdr,
453 				  struct snd_emu10k1_memblk *blk,
454 				  int *first_page_ret, int *last_page_ret)
455 {
456 	struct list_head *p;
457 	struct snd_emu10k1_memblk *q;
458 	int first_page, last_page;
459 	first_page = blk->first_page;
460 	p = blk->mem.list.prev;
461 	if (p != &hdr->block) {
462 		q = get_emu10k1_memblk(p, mem.list);
463 		if (q->last_page == first_page)
464 			first_page++;  /* first page was already allocated */
465 	}
466 	last_page = blk->last_page;
467 	p = blk->mem.list.next;
468 	if (p != &hdr->block) {
469 		q = get_emu10k1_memblk(p, mem.list);
470 		if (q->first_page == last_page)
471 			last_page--; /* last page was already allocated */
472 	}
473 	*first_page_ret = first_page;
474 	*last_page_ret = last_page;
475 }
476 
477 /* release allocated pages */
__synth_free_pages(struct snd_emu10k1 * emu,int first_page,int last_page)478 static void __synth_free_pages(struct snd_emu10k1 *emu, int first_page,
479 			       int last_page)
480 {
481 	struct snd_dma_buffer dmab;
482 	int page;
483 
484 	dmab.dev.type = SNDRV_DMA_TYPE_DEV;
485 	dmab.dev.dev = &emu->pci->dev;
486 
487 	for (page = first_page; page <= last_page; page++) {
488 		if (emu->page_ptr_table[page] == NULL)
489 			continue;
490 		dmab.area = emu->page_ptr_table[page];
491 		dmab.addr = emu->page_addr_table[page];
492 
493 		/*
494 		 * please keep me in sync with logic in
495 		 * snd_emu10k1_alloc_pages_maybe_wider()
496 		 */
497 		dmab.bytes = PAGE_SIZE;
498 		if (emu->iommu_workaround)
499 			dmab.bytes *= 2;
500 
501 		snd_dma_free_pages(&dmab);
502 		emu->page_addr_table[page] = 0;
503 		emu->page_ptr_table[page] = NULL;
504 	}
505 }
506 
507 /*
508  * allocate kernel pages
509  */
synth_alloc_pages(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)510 static int synth_alloc_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
511 {
512 	int page, first_page, last_page;
513 	struct snd_dma_buffer dmab;
514 
515 	emu10k1_memblk_init(blk);
516 	get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
517 	/* allocate kernel pages */
518 	for (page = first_page; page <= last_page; page++) {
519 		if (snd_emu10k1_alloc_pages_maybe_wider(emu, PAGE_SIZE,
520 							&dmab) < 0)
521 			goto __fail;
522 		if (!is_valid_page(emu, dmab.addr)) {
523 			snd_dma_free_pages(&dmab);
524 			goto __fail;
525 		}
526 		emu->page_addr_table[page] = dmab.addr;
527 		emu->page_ptr_table[page] = dmab.area;
528 	}
529 	return 0;
530 
531 __fail:
532 	/* release allocated pages */
533 	last_page = page - 1;
534 	__synth_free_pages(emu, first_page, last_page);
535 
536 	return -ENOMEM;
537 }
538 
539 /*
540  * free pages
541  */
synth_free_pages(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)542 static int synth_free_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
543 {
544 	int first_page, last_page;
545 
546 	get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
547 	__synth_free_pages(emu, first_page, last_page);
548 	return 0;
549 }
550 
551 /* calculate buffer pointer from offset address */
offset_ptr(struct snd_emu10k1 * emu,int page,int offset)552 static inline void *offset_ptr(struct snd_emu10k1 *emu, int page, int offset)
553 {
554 	char *ptr;
555 	if (snd_BUG_ON(page < 0 || page >= emu->max_cache_pages))
556 		return NULL;
557 	ptr = emu->page_ptr_table[page];
558 	if (! ptr) {
559 		dev_err(emu->card->dev,
560 			"access to NULL ptr: page = %d\n", page);
561 		return NULL;
562 	}
563 	ptr += offset & (PAGE_SIZE - 1);
564 	return (void*)ptr;
565 }
566 
567 /*
568  * bzero(blk + offset, size)
569  */
snd_emu10k1_synth_bzero(struct snd_emu10k1 * emu,struct snd_util_memblk * blk,int offset,int size)570 int snd_emu10k1_synth_bzero(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
571 			    int offset, int size)
572 {
573 	int page, nextofs, end_offset, temp, temp1;
574 	void *ptr;
575 	struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
576 
577 	offset += blk->offset & (PAGE_SIZE - 1);
578 	end_offset = offset + size;
579 	page = get_aligned_page(offset);
580 	do {
581 		nextofs = aligned_page_offset(page + 1);
582 		temp = nextofs - offset;
583 		temp1 = end_offset - offset;
584 		if (temp1 < temp)
585 			temp = temp1;
586 		ptr = offset_ptr(emu, page + p->first_page, offset);
587 		if (ptr)
588 			memset(ptr, 0, temp);
589 		offset = nextofs;
590 		page++;
591 	} while (offset < end_offset);
592 	return 0;
593 }
594 
595 EXPORT_SYMBOL(snd_emu10k1_synth_bzero);
596 
597 /*
598  * copy_from_user(blk + offset, data, size)
599  */
snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 * emu,struct snd_util_memblk * blk,int offset,const char __user * data,int size)600 int snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
601 				     int offset, const char __user *data, int size)
602 {
603 	int page, nextofs, end_offset, temp, temp1;
604 	void *ptr;
605 	struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
606 
607 	offset += blk->offset & (PAGE_SIZE - 1);
608 	end_offset = offset + size;
609 	page = get_aligned_page(offset);
610 	do {
611 		nextofs = aligned_page_offset(page + 1);
612 		temp = nextofs - offset;
613 		temp1 = end_offset - offset;
614 		if (temp1 < temp)
615 			temp = temp1;
616 		ptr = offset_ptr(emu, page + p->first_page, offset);
617 		if (ptr && copy_from_user(ptr, data, temp))
618 			return -EFAULT;
619 		offset = nextofs;
620 		data += temp;
621 		page++;
622 	} while (offset < end_offset);
623 	return 0;
624 }
625 
626 EXPORT_SYMBOL(snd_emu10k1_synth_copy_from_user);
627