/* * 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/kobject.h> #include <linux/blkdev.h> #include <linux/blk-mq.h> #include <linux/blk-mq-pci.h> #include <linux/pci.h> #include <linux/module.h> /** * blk_mq_pci_map_queues - provide a default queue mapping for PCI device * @set: tagset to provide the mapping for * @pdev: PCI device associated with @set. * * This function assumes the PCI device @pdev 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_pci_map_queues(struct blk_mq_tag_set *set, struct pci_dev *pdev) { const struct cpumask *mask; unsigned int queue, cpu; for (queue = 0; queue < set->nr_hw_queues; queue++) { mask = pci_irq_get_affinity(pdev, queue); if (!mask) return -EINVAL; for_each_cpu(cpu, mask) set->mq_map[cpu] = queue; } return 0; } EXPORT_SYMBOL_GPL(blk_mq_pci_map_queues);