linux/block/blk-mq-virtio.c
Bart Van Assche a4e1d0b76e block: Change the return type of blk_mq_map_queues() into void
Since blk_mq_map_queues() and the .map_queues() callbacks always return 0,
change their return type into void. Most callers ignore the returned value
anyway.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20220815170043.19489-3-bvanassche@acm.org
[axboe: fold in fix from Bart]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-22 10:07:53 -06:00

48 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2016 Christoph Hellwig.
*/
#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
* @qmap: CPU to hardware queue map.
* @vdev: virtio device to provide a mapping for.
* @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 vectors as @set has queues. It will then query 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.
*/
void blk_mq_virtio_map_queues(struct blk_mq_queue_map *qmap,
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 < qmap->nr_queues; queue++) {
mask = vdev->config->get_vq_affinity(vdev, first_vec + queue);
if (!mask)
goto fallback;
for_each_cpu(cpu, mask)
qmap->mq_map[cpu] = qmap->queue_offset + queue;
}
return;
fallback:
blk_mq_map_queues(qmap);
}
EXPORT_SYMBOL_GPL(blk_mq_virtio_map_queues);