projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 973c4e37 CH |
1 | /* |
| 2 | * Copyright (c) 2016 Christoph Hellwig. | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify it | |
| 5 | * under the terms and conditions of the GNU General Public License, | |
| 6 | * version 2, as published by the Free Software Foundation. | |
| 7 | * | |
| 8 | * This program is distributed in the hope it will be useful, but WITHOUT | |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
| 11 | * more details. | |
| 12 | */ | |
| 8ec2ef2b SR |
13 | #include <linux/kobject.h> |
| 14 | #include <linux/blkdev.h> | |
| 973c4e37 CH |
15 | #include <linux/blk-mq.h> |
| 16 | #include <linux/blk-mq-pci.h> | |
| 17 | #include <linux/pci.h> | |
| 18 | #include <linux/module.h> | |
| 19 | ||
| 0da73d00 MI |
20 | #include "blk-mq.h" |
| 21 | ||
| 973c4e37 CH |
22 | /** |
| 23 | * blk_mq_pci_map_queues - provide a default queue mapping for PCI device | |
| 24 | * @set: tagset to provide the mapping for | |
| 25 | * @pdev: PCI device associated with @set. | |
| f23f5bec | 26 | * @offset: Offset to use for the pci irq vector |
| 973c4e37 CH |
27 | * |
| 28 | * This function assumes the PCI device @pdev has at least as many available | |
| 018c259b | 29 | * interrupt vectors as @set has queues. It will then query the vector |
| 973c4e37 CH |
30 | * corresponding to each queue for it's affinity mask and built queue mapping |
| 31 | * that maps a queue to the CPUs that have irq affinity for the corresponding | |
| 32 | * vector. | |
| 33 | */ | |
| ed76e329 | 34 | int blk_mq_pci_map_queues(struct blk_mq_queue_map *qmap, struct pci_dev *pdev, |
| f23f5bec | 35 | int offset) |
| 973c4e37 CH |
36 | { |
| 37 | const struct cpumask *mask; | |
| 38 | unsigned int queue, cpu; | |
| 39 | ||
| ed76e329 | 40 | for (queue = 0; queue < qmap->nr_queues; queue++) { |
| f23f5bec | 41 | mask = pci_irq_get_affinity(pdev, queue + offset); |
| 973c4e37 | 42 | if (!mask) |
| c0053903 | 43 | goto fallback; |
| 973c4e37 CH |
44 | |
| 45 | for_each_cpu(cpu, mask) | |
| 843477d4 | 46 | qmap->mq_map[cpu] = qmap->queue_offset + queue; |
| 973c4e37 CH |
47 | } |
| 48 | ||
| 49 | return 0; | |
| c0053903 CH |
50 | |
| 51 | fallback: | |
| ed76e329 JA |
52 | WARN_ON_ONCE(qmap->nr_queues > 1); |
| 53 | blk_mq_clear_mq_map(qmap); | |
| c0053903 | 54 | return 0; |
| 973c4e37 CH |
55 | } |
| 56 | EXPORT_SYMBOL_GPL(blk_mq_pci_map_queues); |