55 lines
1.7 KiB
C
55 lines
1.7 KiB
C
|
/*
|
||
|
|
* Copyright (c) 2016 Christoph Hellwig.
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify it
|
||
|
|
* under the terms and conditions of the GNU General Public License,
|
||
|
|
* version 2, as published by the Free Software Foundation.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope it will be useful, but WITHOUT
|
||
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
||
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
||
|
|
* more details.
|
||
|
|
*/
|
||
|
|
#include <linux/device.h>
|
||
|
|
#include <linux/blk-mq.h>
|
||
|
|
#include <linux/blk-mq-virtio.h>
|
||
|
|
#include <linux/virtio_config.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include "blk-mq.h"
|
||
|
|
|
||
|
|
/**
|
||
|
|
* blk_mq_virtio_map_queues - provide a default queue mapping for virtio device
|
||
|
|
* @set: tagset to provide the mapping for
|
||
|
|
* @vdev: virtio device associated with @set.
|
||
|
|
* @first_vec: first interrupt vectors to use for queues (usually 0)
|
||
|
|
*
|
||
|
|
* This function assumes the virtio device @vdev has at least as many available
|
||
|
|
* interrupt vetors as @set has queues. It will then queuery the vector
|
||
|
|
* corresponding to each queue for it's affinity mask and built queue mapping
|
||
|
|
* that maps a queue to the CPUs that have irq affinity for the corresponding
|
||
|
|
* vector.
|
||
|
|
*/
|
||
|
|
int blk_mq_virtio_map_queues(struct blk_mq_tag_set *set,
|
||
|
|
struct virtio_device *vdev, int first_vec)
|
||
|
|
{
|
||
|
|
const struct cpumask *mask;
|
||
|
|
unsigned int queue, cpu;
|
||
|
|
|
||
|
|
if (!vdev->config->get_vq_affinity)
|
||
|
|
goto fallback;
|
||
|
|
|
||
|
|
for (queue = 0; queue < set->nr_hw_queues; queue++) {
|
||
|
|
mask = vdev->config->get_vq_affinity(vdev, first_vec + queue);
|
||
|
|
if (!mask)
|
||
|
|
goto fallback;
|
||
|
|
|
||
|
|
for_each_cpu(cpu, mask)
|
||
|
|
set->mq_map[cpu] = queue;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
fallback:
|
||
|
|
return blk_mq_map_queues(set);
|
||
|
|
}
|
||
|
|
EXPORT_SYMBOL_GPL(blk_mq_virtio_map_queues);
|