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// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/* Copyright (c) 2010-2012 Broadcom. All rights reserved. */
#include "vchiq_util.h"
static inline int is_pow2(int i)
{
return i && !(i & (i - 1));
}
int vchiu_queue_init(struct vchiu_queue *queue, int size)
{
WARN_ON(!is_pow2(size));
queue->size = size;
queue->read = 0;
queue->write = 0;
queue->initialized = 1;
init_completion(&queue->pop);
init_completion(&queue->push);
queue->storage = kcalloc(size, sizeof(struct vchiq_header *),
GFP_KERNEL);
if (!queue->storage) {
vchiu_queue_delete(queue);
return 0;
}
return 1;
}
void vchiu_queue_delete(struct vchiu_queue *queue)
{
kfree(queue->storage);
}
int vchiu_queue_is_empty(struct vchiu_queue *queue)
{
return queue->read == queue->write;
}
void vchiu_queue_push(struct vchiu_queue *queue, struct vchiq_header *header)
{
if (!queue->initialized)
return;
while (queue->write == queue->read + queue->size) {
if (wait_for_completion_interruptible(&queue->pop))
flush_signals(current);
}
queue->storage[queue->write & (queue->size - 1)] = header;
queue->write++;
complete(&queue->push);
}
struct vchiq_header *vchiu_queue_peek(struct vchiu_queue *queue)
{
while (queue->write == queue->read) {
if (wait_for_completion_interruptible(&queue->push))
flush_signals(current);
}
complete(&queue->push); // We haven't removed anything from the queue.
return queue->storage[queue->read & (queue->size - 1)];
}
struct vchiq_header *vchiu_queue_pop(struct vchiu_queue *queue)
{
struct vchiq_header *header;
while (queue->write == queue->read) {
if (wait_for_completion_interruptible(&queue->push))
flush_signals(current);
}
header = queue->storage[queue->read & (queue->size - 1)];
queue->read++;
complete(&queue->pop);
return header;
}
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