xref: /openbmc/linux/sound/core/memalloc.c (revision e0d07278)
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(pool, size, &dmab->addr);
81 }
82 
83 /**
84  * snd_free_dev_iram - free allocated specific memory from on-chip internal ram
85  * @dmab: buffer allocation record to store the allocated data
86  */
87 static void snd_free_dev_iram(struct snd_dma_buffer *dmab)
88 {
89 	struct gen_pool *pool = dmab->private_data;
90 
91 	if (pool && dmab->area)
92 		gen_pool_free(pool, (unsigned long)dmab->area, dmab->bytes);
93 }
94 #endif /* CONFIG_GENERIC_ALLOCATOR */
95 #endif /* CONFIG_HAS_DMA */
96 
97 /*
98  *
99  *  ALSA generic memory management
100  *
101  */
102 
103 static inline gfp_t snd_mem_get_gfp_flags(const struct device *dev,
104 					  gfp_t default_gfp)
105 {
106 	if (!dev)
107 		return default_gfp;
108 	else
109 		return (__force gfp_t)(unsigned long)dev;
110 }
111 
112 /**
113  * snd_dma_alloc_pages - allocate the buffer area according to the given type
114  * @type: the DMA buffer type
115  * @device: the device pointer
116  * @size: the buffer size to allocate
117  * @dmab: buffer allocation record to store the allocated data
118  *
119  * Calls the memory-allocator function for the corresponding
120  * buffer type.
121  *
122  * Return: Zero if the buffer with the given size is allocated successfully,
123  * otherwise a negative value on error.
124  */
125 int snd_dma_alloc_pages(int type, struct device *device, size_t size,
126 			struct snd_dma_buffer *dmab)
127 {
128 	gfp_t gfp;
129 
130 	if (WARN_ON(!size))
131 		return -ENXIO;
132 	if (WARN_ON(!dmab))
133 		return -ENXIO;
134 
135 	dmab->dev.type = type;
136 	dmab->dev.dev = device;
137 	dmab->bytes = 0;
138 	dmab->area = NULL;
139 	dmab->addr = 0;
140 	dmab->private_data = NULL;
141 	switch (type) {
142 	case SNDRV_DMA_TYPE_CONTINUOUS:
143 		gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL);
144 		dmab->area = alloc_pages_exact(size, gfp);
145 		break;
146 	case SNDRV_DMA_TYPE_VMALLOC:
147 		gfp = snd_mem_get_gfp_flags(device, GFP_KERNEL | __GFP_HIGHMEM);
148 		dmab->area = __vmalloc(size, gfp);
149 		break;
150 #ifdef CONFIG_HAS_DMA
151 #ifdef CONFIG_GENERIC_ALLOCATOR
152 	case SNDRV_DMA_TYPE_DEV_IRAM:
153 		snd_malloc_dev_iram(dmab, size);
154 		if (dmab->area)
155 			break;
156 		/* Internal memory might have limited size and no enough space,
157 		 * so if we fail to malloc, try to fetch memory traditionally.
158 		 */
159 		dmab->dev.type = SNDRV_DMA_TYPE_DEV;
160 #endif /* CONFIG_GENERIC_ALLOCATOR */
161 		fallthrough;
162 	case SNDRV_DMA_TYPE_DEV:
163 	case SNDRV_DMA_TYPE_DEV_UC:
164 		snd_malloc_dev_pages(dmab, size);
165 		break;
166 #endif
167 #ifdef CONFIG_SND_DMA_SGBUF
168 	case SNDRV_DMA_TYPE_DEV_SG:
169 	case SNDRV_DMA_TYPE_DEV_UC_SG:
170 		snd_malloc_sgbuf_pages(device, size, dmab, NULL);
171 		break;
172 #endif
173 	default:
174 		pr_err("snd-malloc: invalid device type %d\n", type);
175 		return -ENXIO;
176 	}
177 	if (! dmab->area)
178 		return -ENOMEM;
179 	dmab->bytes = size;
180 	return 0;
181 }
182 EXPORT_SYMBOL(snd_dma_alloc_pages);
183 
184 /**
185  * snd_dma_alloc_pages_fallback - allocate the buffer area according to the given type with fallback
186  * @type: the DMA buffer type
187  * @device: the device pointer
188  * @size: the buffer size to allocate
189  * @dmab: buffer allocation record to store the allocated data
190  *
191  * Calls the memory-allocator function for the corresponding
192  * buffer type.  When no space is left, this function reduces the size and
193  * tries to allocate again.  The size actually allocated is stored in
194  * res_size argument.
195  *
196  * Return: Zero if the buffer with the given size is allocated successfully,
197  * otherwise a negative value on error.
198  */
199 int snd_dma_alloc_pages_fallback(int type, struct device *device, size_t size,
200 				 struct snd_dma_buffer *dmab)
201 {
202 	int err;
203 
204 	while ((err = snd_dma_alloc_pages(type, device, size, dmab)) < 0) {
205 		if (err != -ENOMEM)
206 			return err;
207 		if (size <= PAGE_SIZE)
208 			return -ENOMEM;
209 		size >>= 1;
210 		size = PAGE_SIZE << get_order(size);
211 	}
212 	if (! dmab->area)
213 		return -ENOMEM;
214 	return 0;
215 }
216 EXPORT_SYMBOL(snd_dma_alloc_pages_fallback);
217 
218 
219 /**
220  * snd_dma_free_pages - release the allocated buffer
221  * @dmab: the buffer allocation record to release
222  *
223  * Releases the allocated buffer via snd_dma_alloc_pages().
224  */
225 void snd_dma_free_pages(struct snd_dma_buffer *dmab)
226 {
227 	switch (dmab->dev.type) {
228 	case SNDRV_DMA_TYPE_CONTINUOUS:
229 		free_pages_exact(dmab->area, dmab->bytes);
230 		break;
231 	case SNDRV_DMA_TYPE_VMALLOC:
232 		vfree(dmab->area);
233 		break;
234 #ifdef CONFIG_HAS_DMA
235 #ifdef CONFIG_GENERIC_ALLOCATOR
236 	case SNDRV_DMA_TYPE_DEV_IRAM:
237 		snd_free_dev_iram(dmab);
238 		break;
239 #endif /* CONFIG_GENERIC_ALLOCATOR */
240 	case SNDRV_DMA_TYPE_DEV:
241 	case SNDRV_DMA_TYPE_DEV_UC:
242 		snd_free_dev_pages(dmab);
243 		break;
244 #endif
245 #ifdef CONFIG_SND_DMA_SGBUF
246 	case SNDRV_DMA_TYPE_DEV_SG:
247 	case SNDRV_DMA_TYPE_DEV_UC_SG:
248 		snd_free_sgbuf_pages(dmab);
249 		break;
250 #endif
251 	default:
252 		pr_err("snd-malloc: invalid device type %d\n", dmab->dev.type);
253 	}
254 }
255 EXPORT_SYMBOL(snd_dma_free_pages);
256