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Linux/sound/pci/emu10k1/memory.c

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  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 */
 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 }
 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 */
 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  */
 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  */
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  */
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         if ((p = blk->mapped_link.prev) != &emu->mapped_link_head) {
173                 q = get_emu10k1_memblk(p, mapped_link);
174                 start_page = q->mapped_page + q->pages;
175         } else
176                 start_page = 1;
177         if ((p = blk->mapped_link.next) != &emu->mapped_link_head) {
178                 q = get_emu10k1_memblk(p, mapped_link);
179                 end_page = q->mapped_page;
180         } else
181                 end_page = (emu->address_mode ? MAX_ALIGN_PAGES1 : MAX_ALIGN_PAGES0);
182 
183         /* remove links */
184         list_del(&blk->mapped_link);
185         list_del(&blk->mapped_order_link);
186         /* clear PTB */
187         mpage = blk->mapped_page;
188         for (pg = blk->first_page; pg <= blk->last_page; pg++) {
189                 set_silent_ptb(emu, mpage);
190                 mpage++;
191         }
192         blk->mapped_page = -1;
193         return end_page - start_page; /* return the new empty size */
194 }
195 
196 /*
197  * search empty pages with the given size, and create a memory block
198  *
199  * unlike synth_alloc the memory block is aligned to the page start
200  */
201 static struct snd_emu10k1_memblk *
202 search_empty(struct snd_emu10k1 *emu, int size)
203 {
204         struct list_head *p;
205         struct snd_emu10k1_memblk *blk;
206         int page, psize;
207 
208         psize = get_aligned_page(size + PAGE_SIZE -1);
209         page = 0;
210         list_for_each(p, &emu->memhdr->block) {
211                 blk = get_emu10k1_memblk(p, mem.list);
212                 if (page + psize <= blk->first_page)
213                         goto __found_pages;
214                 page = blk->last_page + 1;
215         }
216         if (page + psize > emu->max_cache_pages)
217                 return NULL;
218 
219 __found_pages:
220         /* create a new memory block */
221         blk = (struct snd_emu10k1_memblk *)__snd_util_memblk_new(emu->memhdr, psize << PAGE_SHIFT, p->prev);
222         if (blk == NULL)
223                 return NULL;
224         blk->mem.offset = aligned_page_offset(page); /* set aligned offset */
225         emu10k1_memblk_init(blk);
226         return blk;
227 }
228 
229 
230 /*
231  * check if the given pointer is valid for pages
232  */
233 static int is_valid_page(struct snd_emu10k1 *emu, dma_addr_t addr)
234 {
235         if (addr & ~emu->dma_mask) {
236                 dev_err_ratelimited(emu->card->dev,
237                         "max memory size is 0x%lx (addr = 0x%lx)!!\n",
238                         emu->dma_mask, (unsigned long)addr);
239                 return 0;
240         }
241         if (addr & (EMUPAGESIZE-1)) {
242                 dev_err_ratelimited(emu->card->dev, "page is not aligned\n");
243                 return 0;
244         }
245         return 1;
246 }
247 
248 /*
249  * map the given memory block on PTB.
250  * if the block is already mapped, update the link order.
251  * if no empty pages are found, tries to release unused memory blocks
252  * and retry the mapping.
253  */
254 int snd_emu10k1_memblk_map(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
255 {
256         int err;
257         int size;
258         struct list_head *p, *nextp;
259         struct snd_emu10k1_memblk *deleted;
260         unsigned long flags;
261 
262         spin_lock_irqsave(&emu->memblk_lock, flags);
263         if (blk->mapped_page >= 0) {
264                 /* update order link */
265                 list_move_tail(&blk->mapped_order_link,
266                                &emu->mapped_order_link_head);
267                 spin_unlock_irqrestore(&emu->memblk_lock, flags);
268                 return 0;
269         }
270         if ((err = map_memblk(emu, blk)) < 0) {
271                 /* no enough page - try to unmap some blocks */
272                 /* starting from the oldest block */
273                 p = emu->mapped_order_link_head.next;
274                 for (; p != &emu->mapped_order_link_head; p = nextp) {
275                         nextp = p->next;
276                         deleted = get_emu10k1_memblk(p, mapped_order_link);
277                         if (deleted->map_locked)
278                                 continue;
279                         size = unmap_memblk(emu, deleted);
280                         if (size >= blk->pages) {
281                                 /* ok the empty region is enough large */
282                                 err = map_memblk(emu, blk);
283                                 break;
284                         }
285                 }
286         }
287         spin_unlock_irqrestore(&emu->memblk_lock, flags);
288         return err;
289 }
290 
291 EXPORT_SYMBOL(snd_emu10k1_memblk_map);
292 
293 /*
294  * page allocation for DMA
295  */
296 struct snd_util_memblk *
297 snd_emu10k1_alloc_pages(struct snd_emu10k1 *emu, struct snd_pcm_substream *substream)
298 {
299         struct snd_pcm_runtime *runtime = substream->runtime;
300         struct snd_util_memhdr *hdr;
301         struct snd_emu10k1_memblk *blk;
302         int page, err, idx;
303 
304         if (snd_BUG_ON(!emu))
305                 return NULL;
306         if (snd_BUG_ON(runtime->dma_bytes <= 0 ||
307                        runtime->dma_bytes >= (emu->address_mode ? MAXPAGES1 : MAXPAGES0) * EMUPAGESIZE))
308                 return NULL;
309         hdr = emu->memhdr;
310         if (snd_BUG_ON(!hdr))
311                 return NULL;
312 
313         idx = runtime->period_size >= runtime->buffer_size ?
314                                         (emu->delay_pcm_irq * 2) : 0;
315         mutex_lock(&hdr->block_mutex);
316         blk = search_empty(emu, runtime->dma_bytes + idx);
317         if (blk == NULL) {
318                 mutex_unlock(&hdr->block_mutex);
319                 return NULL;
320         }
321         /* fill buffer addresses but pointers are not stored so that
322          * snd_free_pci_page() is not called in in synth_free()
323          */
324         idx = 0;
325         for (page = blk->first_page; page <= blk->last_page; page++, idx++) {
326                 unsigned long ofs = idx << PAGE_SHIFT;
327                 dma_addr_t addr;
328                 if (ofs >= runtime->dma_bytes)
329                         addr = emu->silent_page.addr;
330                 else
331                         addr = snd_pcm_sgbuf_get_addr(substream, ofs);
332                 if (! is_valid_page(emu, addr)) {
333                         dev_err_ratelimited(emu->card->dev,
334                                 "emu: failure page = %d\n", idx);
335                         mutex_unlock(&hdr->block_mutex);
336                         return NULL;
337                 }
338                 emu->page_addr_table[page] = addr;
339                 emu->page_ptr_table[page] = NULL;
340         }
341 
342         /* set PTB entries */
343         blk->map_locked = 1; /* do not unmap this block! */
344         err = snd_emu10k1_memblk_map(emu, blk);
345         if (err < 0) {
346                 __snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
347                 mutex_unlock(&hdr->block_mutex);
348                 return NULL;
349         }
350         mutex_unlock(&hdr->block_mutex);
351         return (struct snd_util_memblk *)blk;
352 }
353 
354 
355 /*
356  * release DMA buffer from page table
357  */
358 int snd_emu10k1_free_pages(struct snd_emu10k1 *emu, struct snd_util_memblk *blk)
359 {
360         if (snd_BUG_ON(!emu || !blk))
361                 return -EINVAL;
362         return snd_emu10k1_synth_free(emu, blk);
363 }
364 
365 /*
366  * allocate DMA pages, widening the allocation if necessary
367  *
368  * See the comment above snd_emu10k1_detect_iommu() in emu10k1_main.c why
369  * this might be needed.
370  *
371  * If you modify this function check whether __synth_free_pages() also needs
372  * changes.
373  */
374 int snd_emu10k1_alloc_pages_maybe_wider(struct snd_emu10k1 *emu, size_t size,
375                                         struct snd_dma_buffer *dmab)
376 {
377         if (emu->iommu_workaround) {
378                 size_t npages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
379                 size_t size_real = npages * PAGE_SIZE;
380 
381                 /*
382                  * The device has been observed to accesses up to 256 extra
383                  * bytes, but use 1k to be safe.
384                  */
385                 if (size_real < size + 1024)
386                         size += PAGE_SIZE;
387         }
388 
389         return snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
390                                    snd_dma_pci_data(emu->pci), size, dmab);
391 }
392 
393 /*
394  * memory allocation using multiple pages (for synth)
395  * Unlike the DMA allocation above, non-contiguous pages are assined.
396  */
397 
398 /*
399  * allocate a synth sample area
400  */
401 struct snd_util_memblk *
402 snd_emu10k1_synth_alloc(struct snd_emu10k1 *hw, unsigned int size)
403 {
404         struct snd_emu10k1_memblk *blk;
405         struct snd_util_memhdr *hdr = hw->memhdr; 
406 
407         mutex_lock(&hdr->block_mutex);
408         blk = (struct snd_emu10k1_memblk *)__snd_util_mem_alloc(hdr, size);
409         if (blk == NULL) {
410                 mutex_unlock(&hdr->block_mutex);
411                 return NULL;
412         }
413         if (synth_alloc_pages(hw, blk)) {
414                 __snd_util_mem_free(hdr, (struct snd_util_memblk *)blk);
415                 mutex_unlock(&hdr->block_mutex);
416                 return NULL;
417         }
418         snd_emu10k1_memblk_map(hw, blk);
419         mutex_unlock(&hdr->block_mutex);
420         return (struct snd_util_memblk *)blk;
421 }
422 
423 EXPORT_SYMBOL(snd_emu10k1_synth_alloc);
424 
425 /*
426  * free a synth sample area
427  */
428 int
429 snd_emu10k1_synth_free(struct snd_emu10k1 *emu, struct snd_util_memblk *memblk)
430 {
431         struct snd_util_memhdr *hdr = emu->memhdr; 
432         struct snd_emu10k1_memblk *blk = (struct snd_emu10k1_memblk *)memblk;
433         unsigned long flags;
434 
435         mutex_lock(&hdr->block_mutex);
436         spin_lock_irqsave(&emu->memblk_lock, flags);
437         if (blk->mapped_page >= 0)
438                 unmap_memblk(emu, blk);
439         spin_unlock_irqrestore(&emu->memblk_lock, flags);
440         synth_free_pages(emu, blk);
441          __snd_util_mem_free(hdr, memblk);
442         mutex_unlock(&hdr->block_mutex);
443         return 0;
444 }
445 
446 EXPORT_SYMBOL(snd_emu10k1_synth_free);
447 
448 /* check new allocation range */
449 static void get_single_page_range(struct snd_util_memhdr *hdr,
450                                   struct snd_emu10k1_memblk *blk,
451                                   int *first_page_ret, int *last_page_ret)
452 {
453         struct list_head *p;
454         struct snd_emu10k1_memblk *q;
455         int first_page, last_page;
456         first_page = blk->first_page;
457         if ((p = blk->mem.list.prev) != &hdr->block) {
458                 q = get_emu10k1_memblk(p, mem.list);
459                 if (q->last_page == first_page)
460                         first_page++;  /* first page was already allocated */
461         }
462         last_page = blk->last_page;
463         if ((p = blk->mem.list.next) != &hdr->block) {
464                 q = get_emu10k1_memblk(p, mem.list);
465                 if (q->first_page == last_page)
466                         last_page--; /* last page was already allocated */
467         }
468         *first_page_ret = first_page;
469         *last_page_ret = last_page;
470 }
471 
472 /* release allocated pages */
473 static void __synth_free_pages(struct snd_emu10k1 *emu, int first_page,
474                                int last_page)
475 {
476         struct snd_dma_buffer dmab;
477         int page;
478 
479         dmab.dev.type = SNDRV_DMA_TYPE_DEV;
480         dmab.dev.dev = snd_dma_pci_data(emu->pci);
481 
482         for (page = first_page; page <= last_page; page++) {
483                 if (emu->page_ptr_table[page] == NULL)
484                         continue;
485                 dmab.area = emu->page_ptr_table[page];
486                 dmab.addr = emu->page_addr_table[page];
487 
488                 /*
489                  * please keep me in sync with logic in
490                  * snd_emu10k1_alloc_pages_maybe_wider()
491                  */
492                 dmab.bytes = PAGE_SIZE;
493                 if (emu->iommu_workaround)
494                         dmab.bytes *= 2;
495 
496                 snd_dma_free_pages(&dmab);
497                 emu->page_addr_table[page] = 0;
498                 emu->page_ptr_table[page] = NULL;
499         }
500 }
501 
502 /*
503  * allocate kernel pages
504  */
505 static int synth_alloc_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
506 {
507         int page, first_page, last_page;
508         struct snd_dma_buffer dmab;
509 
510         emu10k1_memblk_init(blk);
511         get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
512         /* allocate kernel pages */
513         for (page = first_page; page <= last_page; page++) {
514                 if (snd_emu10k1_alloc_pages_maybe_wider(emu, PAGE_SIZE,
515                                                         &dmab) < 0)
516                         goto __fail;
517                 if (!is_valid_page(emu, dmab.addr)) {
518                         snd_dma_free_pages(&dmab);
519                         goto __fail;
520                 }
521                 emu->page_addr_table[page] = dmab.addr;
522                 emu->page_ptr_table[page] = dmab.area;
523         }
524         return 0;
525 
526 __fail:
527         /* release allocated pages */
528         last_page = page - 1;
529         __synth_free_pages(emu, first_page, last_page);
530 
531         return -ENOMEM;
532 }
533 
534 /*
535  * free pages
536  */
537 static int synth_free_pages(struct snd_emu10k1 *emu, struct snd_emu10k1_memblk *blk)
538 {
539         int first_page, last_page;
540 
541         get_single_page_range(emu->memhdr, blk, &first_page, &last_page);
542         __synth_free_pages(emu, first_page, last_page);
543         return 0;
544 }
545 
546 /* calculate buffer pointer from offset address */
547 static inline void *offset_ptr(struct snd_emu10k1 *emu, int page, int offset)
548 {
549         char *ptr;
550         if (snd_BUG_ON(page < 0 || page >= emu->max_cache_pages))
551                 return NULL;
552         ptr = emu->page_ptr_table[page];
553         if (! ptr) {
554                 dev_err(emu->card->dev,
555                         "access to NULL ptr: page = %d\n", page);
556                 return NULL;
557         }
558         ptr += offset & (PAGE_SIZE - 1);
559         return (void*)ptr;
560 }
561 
562 /*
563  * bzero(blk + offset, size)
564  */
565 int snd_emu10k1_synth_bzero(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
566                             int offset, int size)
567 {
568         int page, nextofs, end_offset, temp, temp1;
569         void *ptr;
570         struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
571 
572         offset += blk->offset & (PAGE_SIZE - 1);
573         end_offset = offset + size;
574         page = get_aligned_page(offset);
575         do {
576                 nextofs = aligned_page_offset(page + 1);
577                 temp = nextofs - offset;
578                 temp1 = end_offset - offset;
579                 if (temp1 < temp)
580                         temp = temp1;
581                 ptr = offset_ptr(emu, page + p->first_page, offset);
582                 if (ptr)
583                         memset(ptr, 0, temp);
584                 offset = nextofs;
585                 page++;
586         } while (offset < end_offset);
587         return 0;
588 }
589 
590 EXPORT_SYMBOL(snd_emu10k1_synth_bzero);
591 
592 /*
593  * copy_from_user(blk + offset, data, size)
594  */
595 int snd_emu10k1_synth_copy_from_user(struct snd_emu10k1 *emu, struct snd_util_memblk *blk,
596                                      int offset, const char __user *data, int size)
597 {
598         int page, nextofs, end_offset, temp, temp1;
599         void *ptr;
600         struct snd_emu10k1_memblk *p = (struct snd_emu10k1_memblk *)blk;
601 
602         offset += blk->offset & (PAGE_SIZE - 1);
603         end_offset = offset + size;
604         page = get_aligned_page(offset);
605         do {
606                 nextofs = aligned_page_offset(page + 1);
607                 temp = nextofs - offset;
608                 temp1 = end_offset - offset;
609                 if (temp1 < temp)
610                         temp = temp1;
611                 ptr = offset_ptr(emu, page + p->first_page, offset);
612                 if (ptr && copy_from_user(ptr, data, temp))
613                         return -EFAULT;
614                 offset = nextofs;
615                 data += temp;
616                 page++;
617         } while (offset < end_offset);
618         return 0;
619 }
620 
621 EXPORT_SYMBOL(snd_emu10k1_synth_copy_from_user);
622 

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