sound/core/memalloc.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
0004  *                   Takashi Iwai <tiwai@suse.de>
0005  *
0006  *  Generic memory allocators
0007  */
0008
0009 #include <linux/slab.h>
0010 #include <linux/mm.h>
0011 #include <linux/dma-mapping.h>
0012 #include <linux/genalloc.h>
0013 #include <linux/highmem.h>
0014 #include <linux/vmalloc.h>
0015 #ifdef CONFIG_X86
0016 #include <asm/set_memory.h>
0017 #endif
0018 #include <sound/memalloc.h>
0019 #include "memalloc_local.h"
0020
0021 static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab);
0022
0023 #ifdef CONFIG_SND_DMA_SGBUF
0024 static void *do_alloc_fallback_pages(struct device *dev, size_t size,
0025                      dma_addr_t *addr, bool wc);
0026 static void do_free_fallback_pages(void *p, size_t size, bool wc);
0027 static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size);
0028 #endif
0029
0030 /* a cast to gfp flag from the dev pointer; for CONTINUOUS and VMALLOC types */
0031 static inline gfp_t snd_mem_get_gfp_flags(const struct snd_dma_buffer *dmab,
0032                       gfp_t default_gfp)
0033 {
0034     if (!dmab->dev.dev)
0035         return default_gfp;
0036     else
0037         return (__force gfp_t)(unsigned long)dmab->dev.dev;
0038 }
0039
0040 static void *__snd_dma_alloc_pages(struct snd_dma_buffer *dmab, size_t size)
0041 {
0042     const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
0043
0044     if (WARN_ON_ONCE(!ops || !ops->alloc))
0045         return NULL;
0046     return ops->alloc(dmab, size);
0047 }
0048
0049 /**
0050  * snd_dma_alloc_dir_pages - allocate the buffer area according to the given
0051  *  type and direction
0052  * @type: the DMA buffer type
0053  * @device: the device pointer
0054  * @dir: DMA direction
0055  * @size: the buffer size to allocate
0056  * @dmab: buffer allocation record to store the allocated data
0057  *
0058  * Calls the memory-allocator function for the corresponding
0059  * buffer type.
0060  *
0061  * Return: Zero if the buffer with the given size is allocated successfully,
0062  * otherwise a negative value on error.
0063  */
0064 int snd_dma_alloc_dir_pages(int type, struct device *device,
0065                 enum dma_data_direction dir, size_t size,
0066                 struct snd_dma_buffer *dmab)
0067 {
0068     if (WARN_ON(!size))
0069         return -ENXIO;
0070     if (WARN_ON(!dmab))
0071         return -ENXIO;
0072
0073     size = PAGE_ALIGN(size);
0074     dmab->dev.type = type;
0075     dmab->dev.dev = device;
0076     dmab->dev.dir = dir;
0077     dmab->bytes = 0;
0078     dmab->addr = 0;
0079     dmab->private_data = NULL;
0080     dmab->area = __snd_dma_alloc_pages(dmab, size);
0081     if (!dmab->area)
0082         return -ENOMEM;
0083     dmab->bytes = size;
0084     return 0;
0085 }
0086 EXPORT_SYMBOL(snd_dma_alloc_dir_pages);
0087
0088 /**
0089  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
0090  * @type: the DMA buffer type
0091  * @device: the device pointer
0092  * @size: the buffer size to allocate
0093  * @dmab: buffer allocation record to store the allocated data
0094  *
0095  * Calls the memory-allocator function for the corresponding
0096  * buffer type.  When no space is left, this function reduces the size and
0097  * tries to allocate again.  The size actually allocated is stored in
0098  * res_size argument.
0099  *
0100  * Return: Zero if the buffer with the given size is allocated successfully,
0101  * otherwise a negative value on error.
0102  */
0103 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
0104                  struct snd_dma_buffer *dmab)
0105 {
0106     int err;
0107
0108     while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
0109         if (err != -ENOMEM)
0110             return err;
0111         if (size <= PAGE_SIZE)
0112             return -ENOMEM;
0113         size >>= 1;
0114         size = PAGE_SIZE << get_order(size);
0115     }
0116     if (! dmab->area)
0117         return -ENOMEM;
0118     return 0;
0119 }
0120 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
0121
0122 /**
0123  * snd_dma_free_pages - release the allocated buffer
0124  * @dmab: the buffer allocation record to release
0125  *
0126  * Releases the allocated buffer via snd_dma_alloc_pages().
0127  */
0128 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
0129 {
0130     const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
0131
0132     if (ops && ops->free)
0133         ops->free(dmab);
0134 }
0135 EXPORT_SYMBOL(snd_dma_free_pages);
0136
0137 /* called by devres */
0138 static void __snd_release_pages(struct device *dev, void *res)
0139 {
0140     snd_dma_free_pages(res);
0141 }
0142
0143 /**
0144  * snd_devm_alloc_dir_pages - allocate the buffer and manage with devres
0145  * @dev: the device pointer
0146  * @type: the DMA buffer type
0147  * @dir: DMA direction
0148  * @size: the buffer size to allocate
0149  *
0150  * Allocate buffer pages depending on the given type and manage using devres.
0151  * The pages will be released automatically at the device removal.
0152  *
0153  * Unlike snd_dma_alloc_pages(), this function requires the real device pointer,
0154  * hence it can't work with SNDRV_DMA_TYPE_CONTINUOUS or
0155  * SNDRV_DMA_TYPE_VMALLOC type.
0156  *
0157  * Return: the snd_dma_buffer object at success, or NULL if failed
0158  */
0159 struct snd_dma_buffer *
0160 snd_devm_alloc_dir_pages(struct device *dev, int type,
0161              enum dma_data_direction dir, size_t size)
0162 {
0163     struct snd_dma_buffer *dmab;
0164     int err;
0165
0166     if (WARN_ON(type == SNDRV_DMA_TYPE_CONTINUOUS ||
0167             type == SNDRV_DMA_TYPE_VMALLOC))
0168         return NULL;
0169
0170     dmab = devres_alloc(__snd_release_pages, sizeof(*dmab), GFP_KERNEL);
0171     if (!dmab)
0172         return NULL;
0173
0174     err = snd_dma_alloc_dir_pages(type, dev, dir, size, dmab);
0175     if (err < 0) {
0176         devres_free(dmab);
0177         return NULL;
0178     }
0179
0180     devres_add(dev, dmab);
0181     return dmab;
0182 }
0183 EXPORT_SYMBOL_GPL(snd_devm_alloc_dir_pages);
0184
0185 /**
0186  * snd_dma_buffer_mmap - perform mmap of the given DMA buffer
0187  * @dmab: buffer allocation information
0188  * @area: VM area information
0189  *
0190  * Return: zero if successful, or a negative error code
0191  */
0192 int snd_dma_buffer_mmap(struct snd_dma_buffer *dmab,
0193             struct vm_area_struct *area)
0194 {
0195     const struct snd_malloc_ops *ops;
0196
0197     if (!dmab)
0198         return -ENOENT;
0199     ops = snd_dma_get_ops(dmab);
0200     if (ops && ops->mmap)
0201         return ops->mmap(dmab, area);
0202     else
0203         return -ENOENT;
0204 }
0205 EXPORT_SYMBOL(snd_dma_buffer_mmap);
0206
0207 #ifdef CONFIG_HAS_DMA
0208 /**
0209  * snd_dma_buffer_sync - sync DMA buffer between CPU and device
0210  * @dmab: buffer allocation information
0211  * @mode: sync mode
0212  */
0213 void snd_dma_buffer_sync(struct snd_dma_buffer *dmab,
0214              enum snd_dma_sync_mode mode)
0215 {
0216     const struct snd_malloc_ops *ops;
0217
0218     if (!dmab || !dmab->dev.need_sync)
0219         return;
0220     ops = snd_dma_get_ops(dmab);
0221     if (ops && ops->sync)
0222         ops->sync(dmab, mode);
0223 }
0224 EXPORT_SYMBOL_GPL(snd_dma_buffer_sync);
0225 #endif /* CONFIG_HAS_DMA */
0226
0227 /**
0228  * snd_sgbuf_get_addr - return the physical address at the corresponding offset
0229  * @dmab: buffer allocation information
0230  * @offset: offset in the ring buffer
0231  *
0232  * Return: the physical address
0233  */
0234 dma_addr_t snd_sgbuf_get_addr(struct snd_dma_buffer *dmab, size_t offset)
0235 {
0236     const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
0237
0238     if (ops && ops->get_addr)
0239         return ops->get_addr(dmab, offset);
0240     else
0241         return dmab->addr + offset;
0242 }
0243 EXPORT_SYMBOL(snd_sgbuf_get_addr);
0244
0245 /**
0246  * snd_sgbuf_get_page - return the physical page at the corresponding offset
0247  * @dmab: buffer allocation information
0248  * @offset: offset in the ring buffer
0249  *
0250  * Return: the page pointer
0251  */
0252 struct page *snd_sgbuf_get_page(struct snd_dma_buffer *dmab, size_t offset)
0253 {
0254     const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
0255
0256     if (ops && ops->get_page)
0257         return ops->get_page(dmab, offset);
0258     else
0259         return virt_to_page(dmab->area + offset);
0260 }
0261 EXPORT_SYMBOL(snd_sgbuf_get_page);
0262
0263 /**
0264  * snd_sgbuf_get_chunk_size - compute the max chunk size with continuous pages
0265  *  on sg-buffer
0266  * @dmab: buffer allocation information
0267  * @ofs: offset in the ring buffer
0268  * @size: the requested size
0269  *
0270  * Return: the chunk size
0271  */
0272 unsigned int snd_sgbuf_get_chunk_size(struct snd_dma_buffer *dmab,
0273                       unsigned int ofs, unsigned int size)
0274 {
0275     const struct snd_malloc_ops *ops = snd_dma_get_ops(dmab);
0276
0277     if (ops && ops->get_chunk_size)
0278         return ops->get_chunk_size(dmab, ofs, size);
0279     else
0280         return size;
0281 }
0282 EXPORT_SYMBOL(snd_sgbuf_get_chunk_size);
0283
0284 /*
0285  * Continuous pages allocator
0286  */
0287 static void *do_alloc_pages(size_t size, dma_addr_t *addr, gfp_t gfp)
0288 {
0289     void *p = alloc_pages_exact(size, gfp);
0290
0291     if (p)
0292         *addr = page_to_phys(virt_to_page(p));
0293     return p;
0294 }
0295
0296 static void *snd_dma_continuous_alloc(struct snd_dma_buffer *dmab, size_t size)
0297 {
0298     return do_alloc_pages(size, &dmab->addr,
0299                   snd_mem_get_gfp_flags(dmab, GFP_KERNEL));
0300 }
0301
0302 static void snd_dma_continuous_free(struct snd_dma_buffer *dmab)
0303 {
0304     free_pages_exact(dmab->area, dmab->bytes);
0305 }
0306
0307 static int snd_dma_continuous_mmap(struct snd_dma_buffer *dmab,
0308                    struct vm_area_struct *area)
0309 {
0310     return remap_pfn_range(area, area->vm_start,
0311                    dmab->addr >> PAGE_SHIFT,
0312                    area->vm_end - area->vm_start,
0313                    area->vm_page_prot);
0314 }
0315
0316 static const struct snd_malloc_ops snd_dma_continuous_ops = {
0317     .alloc = snd_dma_continuous_alloc,
0318     .free = snd_dma_continuous_free,
0319     .mmap = snd_dma_continuous_mmap,
0320 };
0321
0322 /*
0323  * VMALLOC allocator
0324  */
0325 static void *snd_dma_vmalloc_alloc(struct snd_dma_buffer *dmab, size_t size)
0326 {
0327     gfp_t gfp = snd_mem_get_gfp_flags(dmab, GFP_KERNEL | __GFP_HIGHMEM);
0328
0329     return __vmalloc(size, gfp);
0330 }
0331
0332 static void snd_dma_vmalloc_free(struct snd_dma_buffer *dmab)
0333 {
0334     vfree(dmab->area);
0335 }
0336
0337 static int snd_dma_vmalloc_mmap(struct snd_dma_buffer *dmab,
0338                 struct vm_area_struct *area)
0339 {
0340     return remap_vmalloc_range(area, dmab->area, 0);
0341 }
0342
0343 #define get_vmalloc_page_addr(dmab, offset) \
0344     page_to_phys(vmalloc_to_page((dmab)->area + (offset)))
0345
0346 static dma_addr_t snd_dma_vmalloc_get_addr(struct snd_dma_buffer *dmab,
0347                        size_t offset)
0348 {
0349     return get_vmalloc_page_addr(dmab, offset) + offset % PAGE_SIZE;
0350 }
0351
0352 static struct page *snd_dma_vmalloc_get_page(struct snd_dma_buffer *dmab,
0353                          size_t offset)
0354 {
0355     return vmalloc_to_page(dmab->area + offset);
0356 }
0357
0358 static unsigned int
0359 snd_dma_vmalloc_get_chunk_size(struct snd_dma_buffer *dmab,
0360                    unsigned int ofs, unsigned int size)
0361 {
0362     unsigned int start, end;
0363     unsigned long addr;
0364
0365     start = ALIGN_DOWN(ofs, PAGE_SIZE);
0366     end = ofs + size - 1; /* the last byte address */
0367     /* check page continuity */
0368     addr = get_vmalloc_page_addr(dmab, start);
0369     for (;;) {
0370         start += PAGE_SIZE;
0371         if (start > end)
0372             break;
0373         addr += PAGE_SIZE;
0374         if (get_vmalloc_page_addr(dmab, start) != addr)
0375             return start - ofs;
0376     }
0377     /* ok, all on continuous pages */
0378     return size;
0379 }
0380
0381 static const struct snd_malloc_ops snd_dma_vmalloc_ops = {
0382     .alloc = snd_dma_vmalloc_alloc,
0383     .free = snd_dma_vmalloc_free,
0384     .mmap = snd_dma_vmalloc_mmap,
0385     .get_addr = snd_dma_vmalloc_get_addr,
0386     .get_page = snd_dma_vmalloc_get_page,
0387     .get_chunk_size = snd_dma_vmalloc_get_chunk_size,
0388 };
0389
0390 #ifdef CONFIG_HAS_DMA
0391 /*
0392  * IRAM allocator
0393  */
0394 #ifdef CONFIG_GENERIC_ALLOCATOR
0395 static void *snd_dma_iram_alloc(struct snd_dma_buffer *dmab, size_t size)
0396 {
0397     struct device *dev = dmab->dev.dev;
0398     struct gen_pool *pool;
0399     void *p;
0400
0401     if (dev->of_node) {
0402         pool = of_gen_pool_get(dev->of_node, "iram", 0);
0403         /* Assign the pool into private_data field */
0404         dmab->private_data = pool;
0405
0406         p = gen_pool_dma_alloc_align(pool, size, &dmab->addr, PAGE_SIZE);
0407         if (p)
0408             return p;
0409     }
0410
0411     /* Internal memory might have limited size and no enough space,
0412      * so if we fail to malloc, try to fetch memory traditionally.
0413      */
0414     dmab->dev.type = SNDRV_DMA_TYPE_DEV;
0415     return __snd_dma_alloc_pages(dmab, size);
0416 }
0417
0418 static void snd_dma_iram_free(struct snd_dma_buffer *dmab)
0419 {
0420     struct gen_pool *pool = dmab->private_data;
0421
0422     if (pool && dmab->area)
0423         gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
0424 }
0425
0426 static int snd_dma_iram_mmap(struct snd_dma_buffer *dmab,
0427                  struct vm_area_struct *area)
0428 {
0429     area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
0430     return remap_pfn_range(area, area->vm_start,
0431                    dmab->addr >> PAGE_SHIFT,
0432                    area->vm_end - area->vm_start,
0433                    area->vm_page_prot);
0434 }
0435
0436 static const struct snd_malloc_ops snd_dma_iram_ops = {
0437     .alloc = snd_dma_iram_alloc,
0438     .free = snd_dma_iram_free,
0439     .mmap = snd_dma_iram_mmap,
0440 };
0441 #endif /* CONFIG_GENERIC_ALLOCATOR */
0442
0443 #define DEFAULT_GFP \
0444     (GFP_KERNEL | \
0445      __GFP_COMP |    /* compound page lets parts be mapped */ \
0446      __GFP_NORETRY | /* don't trigger OOM-killer */ \
0447      __GFP_NOWARN)   /* no stack trace print - this call is non-critical */
0448
0449 /*
0450  * Coherent device pages allocator
0451  */
0452 static void *snd_dma_dev_alloc(struct snd_dma_buffer *dmab, size_t size)
0453 {
0454     return dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP);
0455 }
0456
0457 static void snd_dma_dev_free(struct snd_dma_buffer *dmab)
0458 {
0459     dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
0460 }
0461
0462 static int snd_dma_dev_mmap(struct snd_dma_buffer *dmab,
0463                 struct vm_area_struct *area)
0464 {
0465     return dma_mmap_coherent(dmab->dev.dev, area,
0466                  dmab->area, dmab->addr, dmab->bytes);
0467 }
0468
0469 static const struct snd_malloc_ops snd_dma_dev_ops = {
0470     .alloc = snd_dma_dev_alloc,
0471     .free = snd_dma_dev_free,
0472     .mmap = snd_dma_dev_mmap,
0473 };
0474
0475 /*
0476  * Write-combined pages
0477  */
0478 /* x86-specific allocations */
0479 #ifdef CONFIG_SND_DMA_SGBUF
0480 static void *snd_dma_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
0481 {
0482     return do_alloc_fallback_pages(dmab->dev.dev, size, &dmab->addr, true);
0483 }
0484
0485 static void snd_dma_wc_free(struct snd_dma_buffer *dmab)
0486 {
0487     do_free_fallback_pages(dmab->area, dmab->bytes, true);
0488 }
0489
0490 static int snd_dma_wc_mmap(struct snd_dma_buffer *dmab,
0491                struct vm_area_struct *area)
0492 {
0493     area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
0494     return snd_dma_continuous_mmap(dmab, area);
0495 }
0496 #else
0497 static void *snd_dma_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
0498 {
0499     return dma_alloc_wc(dmab->dev.dev, size, &dmab->addr, DEFAULT_GFP);
0500 }
0501
0502 static void snd_dma_wc_free(struct snd_dma_buffer *dmab)
0503 {
0504     dma_free_wc(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
0505 }
0506
0507 static int snd_dma_wc_mmap(struct snd_dma_buffer *dmab,
0508                struct vm_area_struct *area)
0509 {
0510     return dma_mmap_wc(dmab->dev.dev, area,
0511                dmab->area, dmab->addr, dmab->bytes);
0512 }
0513 #endif /* CONFIG_SND_DMA_SGBUF */
0514
0515 static const struct snd_malloc_ops snd_dma_wc_ops = {
0516     .alloc = snd_dma_wc_alloc,
0517     .free = snd_dma_wc_free,
0518     .mmap = snd_dma_wc_mmap,
0519 };
0520
0521 /*
0522  * Non-contiguous pages allocator
0523  */
0524 static void *snd_dma_noncontig_alloc(struct snd_dma_buffer *dmab, size_t size)
0525 {
0526     struct sg_table *sgt;
0527     void *p;
0528
0529     sgt = dma_alloc_noncontiguous(dmab->dev.dev, size, dmab->dev.dir,
0530                       DEFAULT_GFP, 0);
0531     if (!sgt) {
0532 #ifdef CONFIG_SND_DMA_SGBUF
0533         if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG)
0534             dmab->dev.type = SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK;
0535         else
0536             dmab->dev.type = SNDRV_DMA_TYPE_DEV_SG_FALLBACK;
0537         return snd_dma_sg_fallback_alloc(dmab, size);
0538 #else
0539         return NULL;
0540 #endif
0541     }
0542
0543     dmab->dev.need_sync = dma_need_sync(dmab->dev.dev,
0544                         sg_dma_address(sgt->sgl));
0545     p = dma_vmap_noncontiguous(dmab->dev.dev, size, sgt);
0546     if (p) {
0547         dmab->private_data = sgt;
0548         /* store the first page address for convenience */
0549         dmab->addr = snd_sgbuf_get_addr(dmab, 0);
0550     } else {
0551         dma_free_noncontiguous(dmab->dev.dev, size, sgt, dmab->dev.dir);
0552     }
0553     return p;
0554 }
0555
0556 static void snd_dma_noncontig_free(struct snd_dma_buffer *dmab)
0557 {
0558     dma_vunmap_noncontiguous(dmab->dev.dev, dmab->area);
0559     dma_free_noncontiguous(dmab->dev.dev, dmab->bytes, dmab->private_data,
0560                    dmab->dev.dir);
0561 }
0562
0563 static int snd_dma_noncontig_mmap(struct snd_dma_buffer *dmab,
0564                   struct vm_area_struct *area)
0565 {
0566     return dma_mmap_noncontiguous(dmab->dev.dev, area,
0567                       dmab->bytes, dmab->private_data);
0568 }
0569
0570 static void snd_dma_noncontig_sync(struct snd_dma_buffer *dmab,
0571                    enum snd_dma_sync_mode mode)
0572 {
0573     if (mode == SNDRV_DMA_SYNC_CPU) {
0574         if (dmab->dev.dir == DMA_TO_DEVICE)
0575             return;
0576         invalidate_kernel_vmap_range(dmab->area, dmab->bytes);
0577         dma_sync_sgtable_for_cpu(dmab->dev.dev, dmab->private_data,
0578                      dmab->dev.dir);
0579     } else {
0580         if (dmab->dev.dir == DMA_FROM_DEVICE)
0581             return;
0582         flush_kernel_vmap_range(dmab->area, dmab->bytes);
0583         dma_sync_sgtable_for_device(dmab->dev.dev, dmab->private_data,
0584                         dmab->dev.dir);
0585     }
0586 }
0587
0588 static inline void snd_dma_noncontig_iter_set(struct snd_dma_buffer *dmab,
0589                           struct sg_page_iter *piter,
0590                           size_t offset)
0591 {
0592     struct sg_table *sgt = dmab->private_data;
0593
0594     __sg_page_iter_start(piter, sgt->sgl, sgt->orig_nents,
0595                  offset >> PAGE_SHIFT);
0596 }
0597
0598 static dma_addr_t snd_dma_noncontig_get_addr(struct snd_dma_buffer *dmab,
0599                          size_t offset)
0600 {
0601     struct sg_dma_page_iter iter;
0602
0603     snd_dma_noncontig_iter_set(dmab, &iter.base, offset);
0604     __sg_page_iter_dma_next(&iter);
0605     return sg_page_iter_dma_address(&iter) + offset % PAGE_SIZE;
0606 }
0607
0608 static struct page *snd_dma_noncontig_get_page(struct snd_dma_buffer *dmab,
0609                            size_t offset)
0610 {
0611     struct sg_page_iter iter;
0612
0613     snd_dma_noncontig_iter_set(dmab, &iter, offset);
0614     __sg_page_iter_next(&iter);
0615     return sg_page_iter_page(&iter);
0616 }
0617
0618 static unsigned int
0619 snd_dma_noncontig_get_chunk_size(struct snd_dma_buffer *dmab,
0620                  unsigned int ofs, unsigned int size)
0621 {
0622     struct sg_dma_page_iter iter;
0623     unsigned int start, end;
0624     unsigned long addr;
0625
0626     start = ALIGN_DOWN(ofs, PAGE_SIZE);
0627     end = ofs + size - 1; /* the last byte address */
0628     snd_dma_noncontig_iter_set(dmab, &iter.base, start);
0629     if (!__sg_page_iter_dma_next(&iter))
0630         return 0;
0631     /* check page continuity */
0632     addr = sg_page_iter_dma_address(&iter);
0633     for (;;) {
0634         start += PAGE_SIZE;
0635         if (start > end)
0636             break;
0637         addr += PAGE_SIZE;
0638         if (!__sg_page_iter_dma_next(&iter) ||
0639             sg_page_iter_dma_address(&iter) != addr)
0640             return start - ofs;
0641     }
0642     /* ok, all on continuous pages */
0643     return size;
0644 }
0645
0646 static const struct snd_malloc_ops snd_dma_noncontig_ops = {
0647     .alloc = snd_dma_noncontig_alloc,
0648     .free = snd_dma_noncontig_free,
0649     .mmap = snd_dma_noncontig_mmap,
0650     .sync = snd_dma_noncontig_sync,
0651     .get_addr = snd_dma_noncontig_get_addr,
0652     .get_page = snd_dma_noncontig_get_page,
0653     .get_chunk_size = snd_dma_noncontig_get_chunk_size,
0654 };
0655
0656 /* x86-specific SG-buffer with WC pages */
0657 #ifdef CONFIG_SND_DMA_SGBUF
0658 #define sg_wc_address(it) ((unsigned long)page_address(sg_page_iter_page(it)))
0659
0660 static void *snd_dma_sg_wc_alloc(struct snd_dma_buffer *dmab, size_t size)
0661 {
0662     void *p = snd_dma_noncontig_alloc(dmab, size);
0663     struct sg_table *sgt = dmab->private_data;
0664     struct sg_page_iter iter;
0665
0666     if (!p)
0667         return NULL;
0668     if (dmab->dev.type != SNDRV_DMA_TYPE_DEV_WC_SG)
0669         return p;
0670     for_each_sgtable_page(sgt, &iter, 0)
0671         set_memory_wc(sg_wc_address(&iter), 1);
0672     return p;
0673 }
0674
0675 static void snd_dma_sg_wc_free(struct snd_dma_buffer *dmab)
0676 {
0677     struct sg_table *sgt = dmab->private_data;
0678     struct sg_page_iter iter;
0679
0680     for_each_sgtable_page(sgt, &iter, 0)
0681         set_memory_wb(sg_wc_address(&iter), 1);
0682     snd_dma_noncontig_free(dmab);
0683 }
0684
0685 static int snd_dma_sg_wc_mmap(struct snd_dma_buffer *dmab,
0686                   struct vm_area_struct *area)
0687 {
0688     area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
0689     return dma_mmap_noncontiguous(dmab->dev.dev, area,
0690                       dmab->bytes, dmab->private_data);
0691 }
0692
0693 static const struct snd_malloc_ops snd_dma_sg_wc_ops = {
0694     .alloc = snd_dma_sg_wc_alloc,
0695     .free = snd_dma_sg_wc_free,
0696     .mmap = snd_dma_sg_wc_mmap,
0697     .sync = snd_dma_noncontig_sync,
0698     .get_addr = snd_dma_noncontig_get_addr,
0699     .get_page = snd_dma_noncontig_get_page,
0700     .get_chunk_size = snd_dma_noncontig_get_chunk_size,
0701 };
0702
0703 /* manual page allocations with wc setup */
0704 static void *do_alloc_fallback_pages(struct device *dev, size_t size,
0705                      dma_addr_t *addr, bool wc)
0706 {
0707     gfp_t gfp = GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN;
0708     void *p;
0709
0710  again:
0711     p = do_alloc_pages(size, addr, gfp);
0712     if (!p || (*addr + size - 1) & ~dev->coherent_dma_mask) {
0713         if (IS_ENABLED(CONFIG_ZONE_DMA32) && !(gfp & GFP_DMA32)) {
0714             gfp |= GFP_DMA32;
0715             goto again;
0716         }
0717         if (IS_ENABLED(CONFIG_ZONE_DMA) && !(gfp & GFP_DMA)) {
0718             gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
0719             goto again;
0720         }
0721     }
0722     if (p && wc)
0723         set_memory_wc((unsigned long)(p), size >> PAGE_SHIFT);
0724     return p;
0725 }
0726
0727 static void do_free_fallback_pages(void *p, size_t size, bool wc)
0728 {
0729     if (wc)
0730         set_memory_wb((unsigned long)(p), size >> PAGE_SHIFT);
0731     free_pages_exact(p, size);
0732 }
0733
0734 /* Fallback SG-buffer allocations for x86 */
0735 struct snd_dma_sg_fallback {
0736     size_t count;
0737     struct page **pages;
0738     dma_addr_t *addrs;
0739 };
0740
0741 static void __snd_dma_sg_fallback_free(struct snd_dma_buffer *dmab,
0742                        struct snd_dma_sg_fallback *sgbuf)
0743 {
0744     bool wc = dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK;
0745     size_t i;
0746
0747     for (i = 0; i < sgbuf->count && sgbuf->pages[i]; i++)
0748         do_free_fallback_pages(page_address(sgbuf->pages[i]), PAGE_SIZE, wc);
0749     kvfree(sgbuf->pages);
0750     kvfree(sgbuf->addrs);
0751     kfree(sgbuf);
0752 }
0753
0754 static void *snd_dma_sg_fallback_alloc(struct snd_dma_buffer *dmab, size_t size)
0755 {
0756     struct snd_dma_sg_fallback *sgbuf;
0757     struct page **pages;
0758     size_t i, count;
0759     void *p;
0760     bool wc = dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK;
0761
0762     sgbuf = kzalloc(sizeof(*sgbuf), GFP_KERNEL);
0763     if (!sgbuf)
0764         return NULL;
0765     count = PAGE_ALIGN(size) >> PAGE_SHIFT;
0766     pages = kvcalloc(count, sizeof(*pages), GFP_KERNEL);
0767     if (!pages)
0768         goto error;
0769     sgbuf->pages = pages;
0770     sgbuf->addrs = kvcalloc(count, sizeof(*sgbuf->addrs), GFP_KERNEL);
0771     if (!sgbuf->addrs)
0772         goto error;
0773
0774     for (i = 0; i < count; sgbuf->count++, i++) {
0775         p = do_alloc_fallback_pages(dmab->dev.dev, PAGE_SIZE,
0776                         &sgbuf->addrs[i], wc);
0777         if (!p)
0778             goto error;
0779         sgbuf->pages[i] = virt_to_page(p);
0780     }
0781
0782     p = vmap(pages, count, VM_MAP, PAGE_KERNEL);
0783     if (!p)
0784         goto error;
0785     dmab->private_data = sgbuf;
0786     /* store the first page address for convenience */
0787     dmab->addr = snd_sgbuf_get_addr(dmab, 0);
0788     return p;
0789
0790  error:
0791     __snd_dma_sg_fallback_free(dmab, sgbuf);
0792     return NULL;
0793 }
0794
0795 static void snd_dma_sg_fallback_free(struct snd_dma_buffer *dmab)
0796 {
0797     vunmap(dmab->area);
0798     __snd_dma_sg_fallback_free(dmab, dmab->private_data);
0799 }
0800
0801 static int snd_dma_sg_fallback_mmap(struct snd_dma_buffer *dmab,
0802                     struct vm_area_struct *area)
0803 {
0804     struct snd_dma_sg_fallback *sgbuf = dmab->private_data;
0805
0806     if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK)
0807         area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
0808     return vm_map_pages(area, sgbuf->pages, sgbuf->count);
0809 }
0810
0811 static const struct snd_malloc_ops snd_dma_sg_fallback_ops = {
0812     .alloc = snd_dma_sg_fallback_alloc,
0813     .free = snd_dma_sg_fallback_free,
0814     .mmap = snd_dma_sg_fallback_mmap,
0815     /* reuse vmalloc helpers */
0816     .get_addr = snd_dma_vmalloc_get_addr,
0817     .get_page = snd_dma_vmalloc_get_page,
0818     .get_chunk_size = snd_dma_vmalloc_get_chunk_size,
0819 };
0820 #endif /* CONFIG_SND_DMA_SGBUF */
0821
0822 /*
0823  * Non-coherent pages allocator
0824  */
0825 static void *snd_dma_noncoherent_alloc(struct snd_dma_buffer *dmab, size_t size)
0826 {
0827     void *p;
0828
0829     p = dma_alloc_noncoherent(dmab->dev.dev, size, &dmab->addr,
0830                   dmab->dev.dir, DEFAULT_GFP);
0831     if (p)
0832         dmab->dev.need_sync = dma_need_sync(dmab->dev.dev, dmab->addr);
0833     return p;
0834 }
0835
0836 static void snd_dma_noncoherent_free(struct snd_dma_buffer *dmab)
0837 {
0838     dma_free_noncoherent(dmab->dev.dev, dmab->bytes, dmab->area,
0839                  dmab->addr, dmab->dev.dir);
0840 }
0841
0842 static int snd_dma_noncoherent_mmap(struct snd_dma_buffer *dmab,
0843                     struct vm_area_struct *area)
0844 {
0845     area->vm_page_prot = vm_get_page_prot(area->vm_flags);
0846     return dma_mmap_pages(dmab->dev.dev, area,
0847                   area->vm_end - area->vm_start,
0848                   virt_to_page(dmab->area));
0849 }
0850
0851 static void snd_dma_noncoherent_sync(struct snd_dma_buffer *dmab,
0852                      enum snd_dma_sync_mode mode)
0853 {
0854     if (mode == SNDRV_DMA_SYNC_CPU) {
0855         if (dmab->dev.dir != DMA_TO_DEVICE)
0856             dma_sync_single_for_cpu(dmab->dev.dev, dmab->addr,
0857                         dmab->bytes, dmab->dev.dir);
0858     } else {
0859         if (dmab->dev.dir != DMA_FROM_DEVICE)
0860             dma_sync_single_for_device(dmab->dev.dev, dmab->addr,
0861                            dmab->bytes, dmab->dev.dir);
0862     }
0863 }
0864
0865 static const struct snd_malloc_ops snd_dma_noncoherent_ops = {
0866     .alloc = snd_dma_noncoherent_alloc,
0867     .free = snd_dma_noncoherent_free,
0868     .mmap = snd_dma_noncoherent_mmap,
0869     .sync = snd_dma_noncoherent_sync,
0870 };
0871
0872 #endif /* CONFIG_HAS_DMA */
0873
0874 /*
0875  * Entry points
0876  */
0877 static const struct snd_malloc_ops *dma_ops[] = {
0878     [SNDRV_DMA_TYPE_CONTINUOUS] = &snd_dma_continuous_ops,
0879     [SNDRV_DMA_TYPE_VMALLOC] = &snd_dma_vmalloc_ops,
0880 #ifdef CONFIG_HAS_DMA
0881     [SNDRV_DMA_TYPE_DEV] = &snd_dma_dev_ops,
0882     [SNDRV_DMA_TYPE_DEV_WC] = &snd_dma_wc_ops,
0883     [SNDRV_DMA_TYPE_NONCONTIG] = &snd_dma_noncontig_ops,
0884     [SNDRV_DMA_TYPE_NONCOHERENT] = &snd_dma_noncoherent_ops,
0885 #ifdef CONFIG_SND_DMA_SGBUF
0886     [SNDRV_DMA_TYPE_DEV_WC_SG] = &snd_dma_sg_wc_ops,
0887 #endif
0888 #ifdef CONFIG_GENERIC_ALLOCATOR
0889     [SNDRV_DMA_TYPE_DEV_IRAM] = &snd_dma_iram_ops,
0890 #endif /* CONFIG_GENERIC_ALLOCATOR */
0891 #ifdef CONFIG_SND_DMA_SGBUF
0892     [SNDRV_DMA_TYPE_DEV_SG_FALLBACK] = &snd_dma_sg_fallback_ops,
0893     [SNDRV_DMA_TYPE_DEV_WC_SG_FALLBACK] = &snd_dma_sg_fallback_ops,
0894 #endif
0895 #endif /* CONFIG_HAS_DMA */
0896 };
0897
0898 static const struct snd_malloc_ops *snd_dma_get_ops(struct snd_dma_buffer *dmab)
0899 {
0900     if (WARN_ON_ONCE(!dmab))
0901         return NULL;
0902     if (WARN_ON_ONCE(dmab->dev.type <= SNDRV_DMA_TYPE_UNKNOWN ||
0903              dmab->dev.type >= ARRAY_SIZE(dma_ops)))
0904         return NULL;
0905     return dma_ops[dmab->dev.type];
0906 }