// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2017 Sagi Grimberg. */ #include <linux/blk-mq.h> #include <linux/blk-mq-rdma.h> #include <rdma/ib_verbs.h> /** * blk_mq_rdma_map_queues - provide a default queue mapping for rdma device * @map: CPU to hardware queue map. * @dev: rdma device to provide a mapping for. * @first_vec: first interrupt vectors to use for queues (usually 0) * * This function assumes the rdma device @dev has at least as many available * interrupt vetors as @set has queues. It will then query it's affinity mask * and built queue mapping that maps a queue to the CPUs that have irq affinity * for the corresponding vector. * * In case either the driver passed a @dev with less vectors than * @set->nr_hw_queues, or @dev does not provide an affinity mask for a * vector, we fallback to the naive mapping. */ int blk_mq_rdma_map_queues(struct blk_mq_queue_map *map, struct ib_device *dev, int first_vec) { const struct cpumask *mask; unsigned int queue, cpu; for (queue = 0; queue < map->nr_queues; queue++) { mask = ib_get_vector_affinity(dev, first_vec + queue); if (!mask) goto fallback; for_each_cpu(cpu, mask) map->mq_map[cpu] = map->queue_offset + queue; } return 0; fallback: return blk_mq_map_queues(map); } EXPORT_SYMBOL_GPL(blk_mq_rdma_map_queues);