Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2000 Takashi Iwai <tiwai@suse.de> |
| 3 | * |
| 4 | * Generic memory management routines for soundcard memory allocation |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 21 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <linux/init.h> |
| 23 | #include <linux/slab.h> |
Paul Gortmaker | da155d5 | 2011-07-15 12:38:28 -0400 | [diff] [blame^] | 24 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <sound/core.h> |
| 26 | #include <sound/util_mem.h> |
| 27 | |
| 28 | MODULE_AUTHOR("Takashi Iwai"); |
| 29 | MODULE_DESCRIPTION("Generic memory management routines for soundcard memory allocation"); |
| 30 | MODULE_LICENSE("GPL"); |
| 31 | |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 32 | #define get_memblk(p) list_entry(p, struct snd_util_memblk, list) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | |
| 34 | /* |
| 35 | * create a new memory manager |
| 36 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 37 | struct snd_util_memhdr * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | snd_util_memhdr_new(int memsize) |
| 39 | { |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 40 | struct snd_util_memhdr *hdr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
Takashi Iwai | 561b220 | 2005-09-09 14:22:34 +0200 | [diff] [blame] | 42 | hdr = kzalloc(sizeof(*hdr), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | if (hdr == NULL) |
| 44 | return NULL; |
| 45 | hdr->size = memsize; |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 46 | mutex_init(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | INIT_LIST_HEAD(&hdr->block); |
| 48 | |
| 49 | return hdr; |
| 50 | } |
| 51 | |
| 52 | /* |
| 53 | * free a memory manager |
| 54 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 55 | void snd_util_memhdr_free(struct snd_util_memhdr *hdr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | { |
| 57 | struct list_head *p; |
| 58 | |
Takashi Iwai | 5e246b8 | 2008-08-08 17:12:47 +0200 | [diff] [blame] | 59 | if (!hdr) |
| 60 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | /* release all blocks */ |
| 62 | while ((p = hdr->block.next) != &hdr->block) { |
| 63 | list_del(p); |
| 64 | kfree(get_memblk(p)); |
| 65 | } |
| 66 | kfree(hdr); |
| 67 | } |
| 68 | |
| 69 | /* |
| 70 | * allocate a memory block (without mutex) |
| 71 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 72 | struct snd_util_memblk * |
| 73 | __snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | { |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 75 | struct snd_util_memblk *blk; |
| 76 | unsigned int units, prev_offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | struct list_head *p; |
| 78 | |
Takashi Iwai | 5e246b8 | 2008-08-08 17:12:47 +0200 | [diff] [blame] | 79 | if (snd_BUG_ON(!hdr || size <= 0)) |
| 80 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | |
| 82 | /* word alignment */ |
| 83 | units = size; |
| 84 | if (units & 1) |
| 85 | units++; |
| 86 | if (units > hdr->size) |
| 87 | return NULL; |
| 88 | |
| 89 | /* look for empty block */ |
| 90 | prev_offset = 0; |
| 91 | list_for_each(p, &hdr->block) { |
| 92 | blk = get_memblk(p); |
| 93 | if (blk->offset - prev_offset >= units) |
| 94 | goto __found; |
| 95 | prev_offset = blk->offset + blk->size; |
| 96 | } |
| 97 | if (hdr->size - prev_offset < units) |
| 98 | return NULL; |
| 99 | |
| 100 | __found: |
| 101 | return __snd_util_memblk_new(hdr, units, p->prev); |
| 102 | } |
| 103 | |
| 104 | |
| 105 | /* |
| 106 | * create a new memory block with the given size |
| 107 | * the block is linked next to prev |
| 108 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 109 | struct snd_util_memblk * |
| 110 | __snd_util_memblk_new(struct snd_util_memhdr *hdr, unsigned int units, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | struct list_head *prev) |
| 112 | { |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 113 | struct snd_util_memblk *blk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 115 | blk = kmalloc(sizeof(struct snd_util_memblk) + hdr->block_extra_size, |
| 116 | GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | if (blk == NULL) |
| 118 | return NULL; |
| 119 | |
Adrian Bunk | 8e6c962 | 2007-07-30 15:40:43 +0200 | [diff] [blame] | 120 | if (prev == &hdr->block) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | blk->offset = 0; |
| 122 | else { |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 123 | struct snd_util_memblk *p = get_memblk(prev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | blk->offset = p->offset + p->size; |
| 125 | } |
| 126 | blk->size = units; |
| 127 | list_add(&blk->list, prev); |
| 128 | hdr->nblocks++; |
| 129 | hdr->used += units; |
| 130 | return blk; |
| 131 | } |
| 132 | |
| 133 | |
| 134 | /* |
| 135 | * allocate a memory block (with mutex) |
| 136 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 137 | struct snd_util_memblk * |
| 138 | snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | { |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 140 | struct snd_util_memblk *blk; |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 141 | mutex_lock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | blk = __snd_util_mem_alloc(hdr, size); |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 143 | mutex_unlock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | return blk; |
| 145 | } |
| 146 | |
| 147 | |
| 148 | /* |
| 149 | * remove the block from linked-list and free resource |
| 150 | * (without mutex) |
| 151 | */ |
| 152 | void |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 153 | __snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | { |
| 155 | list_del(&blk->list); |
| 156 | hdr->nblocks--; |
| 157 | hdr->used -= blk->size; |
| 158 | kfree(blk); |
| 159 | } |
| 160 | |
| 161 | /* |
| 162 | * free a memory block (with mutex) |
| 163 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 164 | int snd_util_mem_free(struct snd_util_memhdr *hdr, struct snd_util_memblk *blk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | { |
Takashi Iwai | 5e246b8 | 2008-08-08 17:12:47 +0200 | [diff] [blame] | 166 | if (snd_BUG_ON(!hdr || !blk)) |
| 167 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 169 | mutex_lock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | __snd_util_mem_free(hdr, blk); |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 171 | mutex_unlock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | return 0; |
| 173 | } |
| 174 | |
| 175 | /* |
| 176 | * return available memory size |
| 177 | */ |
Takashi Iwai | 03da312 | 2005-11-17 14:24:47 +0100 | [diff] [blame] | 178 | int snd_util_mem_avail(struct snd_util_memhdr *hdr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | { |
| 180 | unsigned int size; |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 181 | mutex_lock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | size = hdr->size - hdr->used; |
Ingo Molnar | ef9f0a4 | 2006-01-16 16:31:42 +0100 | [diff] [blame] | 183 | mutex_unlock(&hdr->block_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | return size; |
| 185 | } |
| 186 | |
| 187 | |
| 188 | EXPORT_SYMBOL(snd_util_memhdr_new); |
| 189 | EXPORT_SYMBOL(snd_util_memhdr_free); |
| 190 | EXPORT_SYMBOL(snd_util_mem_alloc); |
| 191 | EXPORT_SYMBOL(snd_util_mem_free); |
| 192 | EXPORT_SYMBOL(snd_util_mem_avail); |
| 193 | EXPORT_SYMBOL(__snd_util_mem_alloc); |
| 194 | EXPORT_SYMBOL(__snd_util_mem_free); |
| 195 | EXPORT_SYMBOL(__snd_util_memblk_new); |
| 196 | |
| 197 | /* |
| 198 | * INIT part |
| 199 | */ |
| 200 | |
| 201 | static int __init alsa_util_mem_init(void) |
| 202 | { |
| 203 | return 0; |
| 204 | } |
| 205 | |
| 206 | static void __exit alsa_util_mem_exit(void) |
| 207 | { |
| 208 | } |
| 209 | |
| 210 | module_init(alsa_util_mem_init) |
| 211 | module_exit(alsa_util_mem_exit) |