1 // SPDX-License-Identifier: GPL-2.0-or-later
32 	hdr->size = memsize;  in snd_util_memhdr_new()
33 	mutex_init(&hdr->block_mutex);  in snd_util_memhdr_new()
34 	INIT_LIST_HEAD(&hdr->block);  in snd_util_memhdr_new()
49 	while ((p = hdr->block.next) != &hdr->block) {  in snd_util_memhdr_free()
57  * allocate a memory block (without mutex)
60 __snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size)  in __snd_util_mem_alloc()  argument
66 	if (snd_BUG_ON(!hdr || size <= 0))  in __snd_util_mem_alloc()
70 	units = size;  in __snd_util_mem_alloc()
73 	if (units > hdr->size)  in __snd_util_mem_alloc()
76 	/* look for empty block */  in __snd_util_mem_alloc()
78 	list_for_each(p, &hdr->block) {  in __snd_util_mem_alloc()
80 		if (blk->offset - prev_offset >= units)  in __snd_util_mem_alloc()
82 		prev_offset = blk->offset + blk->size;  in __snd_util_mem_alloc()
84 	if (hdr->size - prev_offset < units)  in __snd_util_mem_alloc()
88 	return __snd_util_memblk_new(hdr, units, p->prev);  in __snd_util_mem_alloc()
93  * create a new memory block with the given size
94  * the block is linked next to prev
102 	blk = kmalloc(sizeof(struct snd_util_memblk) + hdr->block_extra_size,  in __snd_util_memblk_new()
107 	if (prev == &hdr->block)  in __snd_util_memblk_new()
108 		blk->offset = 0;  in __snd_util_memblk_new()
111 		blk->offset = p->offset + p->size;  in __snd_util_memblk_new()
113 	blk->size = units;  in __snd_util_memblk_new()
114 	list_add(&blk->list, prev);  in __snd_util_memblk_new()
115 	hdr->nblocks++;  in __snd_util_memblk_new()
116 	hdr->used += units;  in __snd_util_memblk_new()
122  * allocate a memory block (with mutex)
125 snd_util_mem_alloc(struct snd_util_memhdr *hdr, int size)  in snd_util_mem_alloc()  argument
128 	mutex_lock(&hdr->block_mutex);  in snd_util_mem_alloc()
129 	blk = __snd_util_mem_alloc(hdr, size);  in snd_util_mem_alloc()
130 	mutex_unlock(&hdr->block_mutex);  in snd_util_mem_alloc()
136  * remove the block from linked-list and free resource
142 	list_del(&blk->list);  in __snd_util_mem_free()
143 	hdr->nblocks--;  in __snd_util_mem_free()
144 	hdr->used -= blk->size;  in __snd_util_mem_free()
149  * free a memory block (with mutex)
154 		return -EINVAL;  in snd_util_mem_free()
156 	mutex_lock(&hdr->block_mutex);  in snd_util_mem_free()
158 	mutex_unlock(&hdr->block_mutex);  in snd_util_mem_free()
163  * return available memory size
167 	unsigned int size;  in snd_util_mem_avail()  local
168 	mutex_lock(&hdr->block_mutex);  in snd_util_mem_avail()
169 	size = hdr->size - hdr->used;  in snd_util_mem_avail()
170 	mutex_unlock(&hdr->block_mutex);  in snd_util_mem_avail()
171 	return size;  in snd_util_mem_avail()