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 	idx = runtime->period_size >= runtime->buffer_size ?
319 					(emu->delay_pcm_irq * 2) : 0;
320 	mutex_lock(&hdr->block_mutex);
321 	blk = search_empty(emu, runtime->dma_bytes + idx);
322 	if (blk == NULL) {
323 		mutex_unlock(&hdr->block_mutex);
324 		return NULL;
325 	}
326 	/* fill buffer addresses but pointers are not stored so that
327 	 * snd_free_pci_page() is not called in in synth_free()
328 	 */
329 	idx = 0;
330 	for (page = blk->first_page; page <= blk->last_page; page++, idx++) {
331 		unsigned long ofs = idx << PAGE_SHIFT;
332 		dma_addr_t addr;
333 		if (ofs >= runtime->dma_bytes)
334 			addr = emu->silent_page.addr;
335 		else
336 			addr = snd_pcm_sgbuf_get_addr(substream, ofs);
337 		if (! is_valid_page(emu, addr)) {
338 			dev_err_ratelimited(emu->card->dev,
339 				"emu: failure page = %d\n", idx);
340 			mutex_unlock(&hdr->block_mutex);
341 			return NULL;
342 		}
343 		emu->page_addr_table[page] = addr;
344 		emu->page_ptr_table[page] = NULL;
345 	}
346 
347 	/* set PTB entries */
348 	blk->map_locked = 1; /* do not unmap this block! */
349 	err = snd_emu10k1_memblk_map(emu, blk);
350 	if (err < 0) {
351 		__snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
352 		mutex_unlock(&hdr->block_mutex);
353 		return NULL;
354 	}
355 	mutex_unlock(&hdr->block_mutex);
356 	return (struct snd_util_memblk *)blk;
357 }
358 
359 
360 /*
361  * release DMA buffer from page table
362  */
snd_emu10k1_free_pages(struct snd_emu10k1 * emu,struct snd_util_memblk * blk)363 int snd_emu10k1_free_pages(struct snd_emu10k1 *emu, struct snd_util_memblk *blk)
364 {
365 	if (snd_BUG_ON(!emu || !blk))
366 		return -EINVAL;
367 	return snd_emu10k1_synth_free(emu, blk);
368 }
369 
370 /*
371  * allocate DMA pages, widening the allocation if necessary
372  *
373  * See the comment above snd_emu10k1_detect_iommu() in emu10k1_main.c why
374  * this might be needed.
375  *
376  * If you modify this function check whether __synth_free_pages() also needs
377  * changes.
378  */
snd_emu10k1_alloc_pages_maybe_wider(struct snd_emu10k1 * emu,size_t size,struct snd_dma_buffer * dmab)379 int snd_emu10k1_alloc_pages_maybe_wider(struct snd_emu10k1 *emu, size_t size,
380 					struct snd_dma_buffer *dmab)
381 {
382 	if (emu->iommu_workaround) {
383 		size_t npages = DIV_ROUND_UP(size, PAGE_SIZE);
384 		size_t size_real = npages * PAGE_SIZE;
385 
386 		/*
387 		 * The device has been observed to accesses up to 256 extra
388 		 * bytes, but use 1k to be safe.
389 		 */
390 		if (size_real < size + 1024)
391 			size += PAGE_SIZE;
392 	}
393 
394 	return snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
395 				   &emu->pci->dev, size, dmab);
396 }
397 
398 /*
399  * memory allocation using multiple pages (for synth)
400  * Unlike the DMA allocation above, non-contiguous pages are assined.
401  */
402 
403 /*
404  * allocate a synth sample area
405  */
406 struct snd_util_memblk *
snd_emu10k1_synth_alloc(struct snd_emu10k1 * hw,unsigned int size)407 snd_emu10k1_synth_alloc(struct snd_emu10k1 *hw, unsigned int size)
408 {
409 	struct snd_emu10k1_memblk *blk;
410 	struct snd_util_memhdr *hdr = hw->memhdr;
411 
412 	mutex_lock(&hdr->block_mutex);
413 	blk = (struct snd_emu10k1_memblk *)__snd_util_mem_alloc(hdr, size);
414 	if (blk == NULL) {
415 		mutex_unlock(&hdr->block_mutex);
416 		return NULL;
417 	}
418 	if (synth_alloc_pages(hw, blk)) {
419 		__snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
420 		mutex_unlock(&hdr->block_mutex);
421 		return NULL;
422 	}
423 	snd_emu10k1_memblk_map(hw, blk);
424 	mutex_unlock(&hdr->block_mutex);
425 	return (struct snd_util_memblk *)blk;
426 }
427 
428 EXPORT_SYMBOL(snd_emu10k1_synth_alloc);
429 
430 /*
431  * free a synth sample area
432  */
433 int
snd_emu10k1_synth_free(struct snd_emu10k1 * emu,struct snd_util_memblk * memblk)434 snd_emu10k1_synth_free(struct snd_emu10k1 *emu, struct snd_util_memblk *memblk)
435 {
436 	struct snd_util_memhdr *hdr = emu->memhdr;
437 	struct snd_emu10k1_memblk *blk = (struct snd_emu10k1_memblk *)memblk;
438 	unsigned long flags;
439 
440 	mutex_lock(&hdr->block_mutex);
441 	spin_lock_irqsave(&emu->memblk_lock, flags);
442 	if (blk->mapped_page >= 0)
443 		unmap_memblk(emu, blk);
444 	spin_unlock_irqrestore(&emu->memblk_lock, flags);
445 	synth_free_pages(emu, blk);
446 	 __snd_util_mem_free(hdr, memblk);
447 	mutex_unlock(&hdr->block_mutex);
448 	return 0;
449 }
450 
451 EXPORT_SYMBOL(snd_emu10k1_synth_free);
452 
453 /* 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)454 static void get_single_page_range(struct snd_util_memhdr *hdr,
455 				  struct snd_emu10k1_memblk *blk,
456 				  int *first_page_ret, int *last_page_ret)
457 {
458 	struct list_head *p;
459 	struct snd_emu10k1_memblk *q;
460 	int first_page, last_page;
461 	first_page = blk->first_page;
462 	p = blk->mem.list.prev;
463 	if (p != &hdr->block) {
464 		q = get_emu10k1_memblk(p, mem.list);
465 		if (q->last_page == first_page)
466 			first_page++;  /* first page was already allocated */
467 	}
468 	last_page = blk->last_page;
469 	p = blk->mem.list.next;
470 	if (p != &hdr->block) {
471 		q = get_emu10k1_memblk(p, mem.list);
472 		if (q->first_page == last_page)
473 			last_page--; /* last page was already allocated */
474 	}
475 	*first_page_ret = first_page;
476 	*last_page_ret = last_page;
477 }
478 
479 /* release allocated pages */
__synth_free_pages(struct snd_emu10k1 * emu,int first_page,int last_page)480 static void __synth_free_pages(struct snd_emu10k1 *emu, int first_page,
481 			       int last_page)
482 {
483 	struct snd_dma_buffer dmab;
484 	int page;
485 
486 	dmab.dev.type = SNDRV_DMA_TYPE_DEV;
487 	dmab.dev.dev = &emu->pci->dev;
488 
489 	for (page = first_page; page <= last_page; page++) {
490 		if (emu->page_ptr_table[page] == NULL)
491 			continue;
492 		dmab.area = emu->page_ptr_table[page];
493 		dmab.addr = emu->page_addr_table[page];
494 
495 		/*
496 		 * please keep me in sync with logic in
497 		 * snd_emu10k1_alloc_pages_maybe_wider()
498 		 */
499 		dmab.bytes = PAGE_SIZE;
500 		if (emu->iommu_workaround)
501 			dmab.bytes *= 2;
502 
503 		snd_dma_free_pages(&dmab);
504 		emu->page_addr_table[page] = 0;
505 		emu->page_ptr_table[page] = NULL;
506 	}
507 }
508 
509 /*
510  * allocate kernel pages
511  */
synth_alloc_pages(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)512 static int synth_alloc_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
513 {
514 	int page, first_page, last_page;
515 	struct snd_dma_buffer dmab;
516 
517 	emu10k1_memblk_init(blk);
518 	get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
519 	/* allocate kernel pages */
520 	for (page = first_page; page <= last_page; page++) {
521 		if (snd_emu10k1_alloc_pages_maybe_wider(emu, PAGE_SIZE,
522 							&dmab) < 0)
523 			goto __fail;
524 		if (!is_valid_page(emu, dmab.addr)) {
525 			snd_dma_free_pages(&dmab);
526 			goto __fail;
527 		}
528 		emu->page_addr_table[page] = dmab.addr;
529 		emu->page_ptr_table[page] = dmab.area;
530 	}
531 	return 0;
532 
533 __fail:
534 	/* release allocated pages */
535 	last_page = page - 1;
536 	__synth_free_pages(emu, first_page, last_page);
537 
538 	return -ENOMEM;
539 }
540 
541 /*
542  * free pages
543  */
synth_free_pages(struct snd_emu10k1 * emu,struct snd_emu10k1_memblk * blk)544 static int synth_free_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
545 {
546 	int first_page, last_page;
547 
548 	get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
549 	__synth_free_pages(emu, first_page, last_page);
550 	return 0;
551 }
552 
553 /* calculate buffer pointer from offset address */
offset_ptr(struct snd_emu10k1 * emu,int page,int offset)554 static inline void *offset_ptr(struct snd_emu10k1 *emu, int page, int offset)
555 {
556 	char *ptr;
557 	if (snd_BUG_ON(page < 0 || page >= emu->max_cache_pages))
558 		return NULL;
559 	ptr = emu->page_ptr_table[page];
560 	if (! ptr) {
561 		dev_err(emu->card->dev,
562 			"access to NULL ptr: page = %d\n", page);
563 		return NULL;
564 	}
565 	ptr += offset & (PAGE_SIZE - 1);
566 	return (void*)ptr;
567 }
568 
569 /*
570  * bzero(blk + offset, size)
571  */
snd_emu10k1_synth_bzero(struct snd_emu10k1 * emu,struct snd_util_memblk * blk,int offset,int size)572 int snd_emu10k1_synth_bzero(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
573 			    int offset, int size)
574 {
575 	int page, nextofs, end_offset, temp, temp1;
576 	void *ptr;
577 	struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
578 
579 	offset += blk->offset & (PAGE_SIZE - 1);
580 	end_offset = offset + size;
581 	page = get_aligned_page(offset);
582 	do {
583 		nextofs = aligned_page_offset(page + 1);
584 		temp = nextofs - offset;
585 		temp1 = end_offset - offset;
586 		if (temp1 < temp)
587 			temp = temp1;
588 		ptr = offset_ptr(emu, page + p->first_page, offset);
589 		if (ptr)
590 			memset(ptr, 0, temp);
591 		offset = nextofs;
592 		page++;
593 	} while (offset < end_offset);
594 	return 0;
595 }
596 
597 EXPORT_SYMBOL(snd_emu10k1_synth_bzero);
598 
599 /*
600  * copy_from_user(blk + offset, data, size)
601  */
snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 * emu,struct snd_util_memblk * blk,int offset,const char __user * data,int size)602 int snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
603 				     int offset, const char __user *data, int size)
604 {
605 	int page, nextofs, end_offset, temp, temp1;
606 	void *ptr;
607 	struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
608 
609 	offset += blk->offset & (PAGE_SIZE - 1);
610 	end_offset = offset + size;
611 	page = get_aligned_page(offset);
612 	do {
613 		nextofs = aligned_page_offset(page + 1);
614 		temp = nextofs - offset;
615 		temp1 = end_offset - offset;
616 		if (temp1 < temp)
617 			temp = temp1;
618 		ptr = offset_ptr(emu, page + p->first_page, offset);
619 		if (ptr && copy_from_user(ptr, data, temp))
620 			return -EFAULT;
621 		offset = nextofs;
622 		data += temp;
623 		page++;
624 	} while (offset < end_offset);
625 	return 0;
626 }
627 
628 EXPORT_SYMBOL(snd_emu10k1_synth_copy_from_user);
629