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-rdma.c (1332B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Copyright (c) 2017 Sagi Grimberg.
      4 */
      5#include <linux/blk-mq.h>
      6#include <linux/blk-mq-rdma.h>
      7#include <rdma/ib_verbs.h>
      8
      9/**
     10 * blk_mq_rdma_map_queues - provide a default queue mapping for rdma device
     11 * @map:	CPU to hardware queue map.
     12 * @dev:	rdma device to provide a mapping for.
     13 * @first_vec:	first interrupt vectors to use for queues (usually 0)
     14 *
     15 * This function assumes the rdma device @dev has at least as many available
     16 * interrupt vetors as @set has queues.  It will then query it's affinity mask
     17 * and built queue mapping that maps a queue to the CPUs that have irq affinity
     18 * for the corresponding vector.
     19 *
     20 * In case either the driver passed a @dev with less vectors than
     21 * @set->nr_hw_queues, or @dev does not provide an affinity mask for a
     22 * vector, we fallback to the naive mapping.
     23 */
     24int blk_mq_rdma_map_queues(struct blk_mq_queue_map *map,
     25		struct ib_device *dev, int first_vec)
     26{
     27	const struct cpumask *mask;
     28	unsigned int queue, cpu;
     29
     30	for (queue = 0; queue < map->nr_queues; queue++) {
     31		mask = ib_get_vector_affinity(dev, first_vec + queue);
     32		if (!mask)
     33			goto fallback;
     34
     35		for_each_cpu(cpu, mask)
     36			map->mq_map[cpu] = map->queue_offset + queue;
     37	}
     38
     39	return 0;
     40
     41fallback:
     42	return blk_mq_map_queues(map);
     43}
     44EXPORT_SYMBOL_GPL(blk_mq_rdma_map_queues);