cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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blk-mq-virtio.c (1365B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Copyright (c) 2016 Christoph Hellwig.
      4 */
      5#include <linux/device.h>
      6#include <linux/blk-mq.h>
      7#include <linux/blk-mq-virtio.h>
      8#include <linux/virtio_config.h>
      9#include <linux/module.h>
     10#include "blk-mq.h"
     11
     12/**
     13 * blk_mq_virtio_map_queues - provide a default queue mapping for virtio device
     14 * @qmap:	CPU to hardware queue map.
     15 * @vdev:	virtio device to provide a mapping for.
     16 * @first_vec:	first interrupt vectors to use for queues (usually 0)
     17 *
     18 * This function assumes the virtio device @vdev has at least as many available
     19 * interrupt vectors as @set has queues.  It will then query the vector
     20 * corresponding to each queue for it's affinity mask and built queue mapping
     21 * that maps a queue to the CPUs that have irq affinity for the corresponding
     22 * vector.
     23 */
     24int blk_mq_virtio_map_queues(struct blk_mq_queue_map *qmap,
     25		struct virtio_device *vdev, int first_vec)
     26{
     27	const struct cpumask *mask;
     28	unsigned int queue, cpu;
     29
     30	if (!vdev->config->get_vq_affinity)
     31		goto fallback;
     32
     33	for (queue = 0; queue < qmap->nr_queues; queue++) {
     34		mask = vdev->config->get_vq_affinity(vdev, first_vec + queue);
     35		if (!mask)
     36			goto fallback;
     37
     38		for_each_cpu(cpu, mask)
     39			qmap->mq_map[cpu] = qmap->queue_offset + queue;
     40	}
     41
     42	return 0;
     43fallback:
     44	return blk_mq_map_queues(qmap);
     45}
     46EXPORT_SYMBOL_GPL(blk_mq_virtio_map_queues);