xref: /openbmc/linux/sound/core/memalloc.c (revision 31e67366)
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 */
27 static 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 */
45 static 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  */
63 static 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  */
88 static 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 
104 static 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  */
126 int 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 }
184 EXPORT_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  */
201 int 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 }
218 EXPORT_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  */
227 void 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 }
257 EXPORT_SYMBOL(snd_dma_free_pages);
258