Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 * Takashi Iwai <tiwai@suse.de>
5 *
6 * Generic memory allocators
7 */
8
9#include <linux/slab.h>
10#include <linux/mm.h>
11#include <linux/dma-mapping.h>
12#include <linux/genalloc.h>
13#include <linux/vmalloc.h>
14#ifdef CONFIG_X86
15#include <asm/set_memory.h>
16#endif
17#include <sound/memalloc.h>
18
19/*
20 *
21 * Bus-specific memory allocators
22 *
23 */
24
25#ifdef CONFIG_HAS_DMA
26/* allocate the coherent DMA pages */
27static void snd_malloc_dev_pages(struct snd_dma_buffer *dmab, size_t size)
28{
29 gfp_t gfp_flags;
30
31 gfp_flags = GFP_KERNEL
32 | __GFP_COMP /* compound page lets parts be mapped */
33 | __GFP_NORETRY /* don't trigger OOM-killer */
34 | __GFP_NOWARN; /* no stack trace print - this call is non-critical */
35 dmab->area = dma_alloc_coherent(dmab->dev.dev, size, &dmab->addr,
36 gfp_flags);
37#ifdef CONFIG_X86
38 if (dmab->area && dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
39 set_memory_wc((unsigned long)dmab->area,
40 PAGE_ALIGN(size) >> PAGE_SHIFT);
41#endif
42}
43
44/* free the coherent DMA pages */
45static void snd_free_dev_pages(struct snd_dma_buffer *dmab)
46{
47#ifdef CONFIG_X86
48 if (dmab->dev.type == SNDRV_DMA_TYPE_DEV_UC)
49 set_memory_wb((unsigned long)dmab->area,
50 PAGE_ALIGN(dmab->bytes) >> PAGE_SHIFT);
51#endif
52 dma_free_coherent(dmab->dev.dev, dmab->bytes, dmab->area, dmab->addr);
53}
54
55#ifdef CONFIG_GENERIC_ALLOCATOR
56/**
57 * snd_malloc_dev_iram - allocate memory from on-chip internal ram
58 * @dmab: buffer allocation record to store the allocated data
59 * @size: number of bytes to allocate from the iram
60 *
61 * This function requires iram phandle provided via of_node
62 */
63static void snd_malloc_dev_iram(struct snd_dma_buffer *dmab, size_t size)
64{
65 struct device *dev = dmab->dev.dev;
66 struct gen_pool *pool = NULL;
67
68 dmab->area = NULL;
69 dmab->addr = 0;
70
71 if (dev->of_node)
72 pool = of_gen_pool_get(dev->of_node, "iram", 0);
73
74 if (!pool)
75 return;
76
77 /* Assign the pool into private_data field */
78 dmab->private_data = pool;
79
80 dmab->area = gen_pool_dma_alloc_align(pool, size, &dmab->addr,
81 PAGE_SIZE);
82}
83
84/**
85 * snd_free_dev_iram - free allocated specific memory from on-chip internal ram
86 * @dmab: buffer allocation record to store the allocated data
87 */
88static void snd_free_dev_iram(struct snd_dma_buffer *dmab)
89{
90 struct gen_pool *pool = dmab->private_data;
91
92 if (pool && dmab->area)
93 gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
94}
95#endif /* CONFIG_GENERIC_ALLOCATOR */
96#endif /* CONFIG_HAS_DMA */
97
98/*
99 *
100 * ALSA generic memory management
101 *
102 */
103
104static inline gfp_t snd_mem_get_gfp_flags(const struct device *dev,
105 gfp_t default_gfp)
106{
107 if (!dev)
108 return default_gfp;
109 else
110 return (__force gfp_t)(unsigned long)dev;
111}
112
113/**
114 * snd_dma_alloc_pages - allocate the buffer area according to the given type
115 * @type: the DMA buffer type
116 * @device: the device pointer
117 * @size: the buffer size to allocate
118 * @dmab: buffer allocation record to store the allocated data
119 *
120 * Calls the memory-allocator function for the corresponding
121 * buffer type.
122 *
123 * Return: Zero if the buffer with the given size is allocated successfully,
124 * otherwise a negative value on error.
125 */
126int snd_dma_alloc_pages(int type, struct device *device, size_t size,
127 struct snd_dma_buffer *dmab)
128{
129 gfp_t gfp;
130
131 if (WARN_ON(!size))
132 return -ENXIO;
133 if (WARN_ON(!dmab))
134 return -ENXIO;
135
136 size = PAGE_ALIGN(size);
137 dmab->dev.type = type;
138 dmab->dev.dev = device;
139 dmab->bytes = 0;
140 dmab->area = NULL;
141 dmab->addr = 0;
142 dmab->private_data = NULL;
143 switch (type) {
144 case SNDRV_DMA_TYPE_CONTINUOUS:
145 gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL);
146 dmab->area = alloc_pages_exact(size, gfp);
147 break;
148 case SNDRV_DMA_TYPE_VMALLOC:
149 gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL | __GFP_HIGHMEM);
150 dmab->area = __vmalloc(size, gfp);
151 break;
152#ifdef CONFIG_HAS_DMA
153#ifdef CONFIG_GENERIC_ALLOCATOR
154 case SNDRV_DMA_TYPE_DEV_IRAM:
155 snd_malloc_dev_iram(dmab, size);
156 if (dmab->area)
157 break;
158 /* Internal memory might have limited size and no enough space,
159 * so if we fail to malloc, try to fetch memory traditionally.
160 */
161 dmab->dev.type = SNDRV_DMA_TYPE_DEV;
162 fallthrough;
163#endif /* CONFIG_GENERIC_ALLOCATOR */
164 case SNDRV_DMA_TYPE_DEV:
165 case SNDRV_DMA_TYPE_DEV_UC:
166 snd_malloc_dev_pages(dmab, size);
167 break;
168#endif
169#ifdef CONFIG_SND_DMA_SGBUF
170 case SNDRV_DMA_TYPE_DEV_SG:
171 case SNDRV_DMA_TYPE_DEV_UC_SG:
172 snd_malloc_sgbuf_pages(device, size, dmab, NULL);
173 break;
174#endif
175 default:
176 pr_err("snd-malloc: invalid device type %d\n", type);
177 return -ENXIO;
178 }
179 if (! dmab->area)
180 return -ENOMEM;
181 dmab->bytes = size;
182 return 0;
183}
184EXPORT_SYMBOL(snd_dma_alloc_pages);
185
186/**
187 * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
188 * @type: the DMA buffer type
189 * @device: the device pointer
190 * @size: the buffer size to allocate
191 * @dmab: buffer allocation record to store the allocated data
192 *
193 * Calls the memory-allocator function for the corresponding
194 * buffer type. When no space is left, this function reduces the size and
195 * tries to allocate again. The size actually allocated is stored in
196 * res_size argument.
197 *
198 * Return: Zero if the buffer with the given size is allocated successfully,
199 * otherwise a negative value on error.
200 */
201int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
202 struct snd_dma_buffer *dmab)
203{
204 int err;
205
206 while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
207 if (err != -ENOMEM)
208 return err;
209 if (size <= PAGE_SIZE)
210 return -ENOMEM;
211 size >>= 1;
212 size = PAGE_SIZE << get_order(size);
213 }
214 if (! dmab->area)
215 return -ENOMEM;
216 return 0;
217}
218EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
219
220
221/**
222 * snd_dma_free_pages - release the allocated buffer
223 * @dmab: the buffer allocation record to release
224 *
225 * Releases the allocated buffer via snd_dma_alloc_pages().
226 */
227void snd_dma_free_pages(struct snd_dma_buffer *dmab)
228{
229 switch (dmab->dev.type) {
230 case SNDRV_DMA_TYPE_CONTINUOUS:
231 free_pages_exact(dmab->area, dmab->bytes);
232 break;
233 case SNDRV_DMA_TYPE_VMALLOC:
234 vfree(dmab->area);
235 break;
236#ifdef CONFIG_HAS_DMA
237#ifdef CONFIG_GENERIC_ALLOCATOR
238 case SNDRV_DMA_TYPE_DEV_IRAM:
239 snd_free_dev_iram(dmab);
240 break;
241#endif /* CONFIG_GENERIC_ALLOCATOR */
242 case SNDRV_DMA_TYPE_DEV:
243 case SNDRV_DMA_TYPE_DEV_UC:
244 snd_free_dev_pages(dmab);
245 break;
246#endif
247#ifdef CONFIG_SND_DMA_SGBUF
248 case SNDRV_DMA_TYPE_DEV_SG:
249 case SNDRV_DMA_TYPE_DEV_UC_SG:
250 snd_free_sgbuf_pages(dmab);
251 break;
252#endif
253 default:
254 pr_err("snd-malloc: invalid device type %d\n", dmab->dev.type);
255 }
256}
257EXPORT_SYMBOL(snd_dma_free_pages);