diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/Kconfig | 5 | ||||
| -rw-r--r-- | block/Makefile | 1 | ||||
| -rw-r--r-- | block/blk-mq-virtio.c | 54 |
3 files changed, 60 insertions, 0 deletions
diff --git a/block/Kconfig b/block/Kconfig index 8bf114a3858a..3523b4f0cd8b 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -165,4 +165,9 @@ config BLK_MQ_PCI depends on BLOCK && PCI default y +config BLK_MQ_VIRTIO + bool + depends on BLOCK && VIRTIO + default y + source block/Kconfig.iosched diff --git a/block/Makefile b/block/Makefile index a827f988c4e6..60691949d28d 100644 --- a/block/Makefile +++ b/block/Makefile @@ -23,5 +23,6 @@ obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o obj-$(CONFIG_BLK_CMDLINE_PARSER) += cmdline-parser.o obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o blk-integrity.o t10-pi.o obj-$(CONFIG_BLK_MQ_PCI) += blk-mq-pci.o +obj-$(CONFIG_BLK_MQ_VIRTIO) += blk-mq-virtio.o obj-$(CONFIG_BLK_DEV_ZONED) += blk-zoned.o obj-$(CONFIG_BLK_WBT) += blk-wbt.o diff --git a/block/blk-mq-virtio.c b/block/blk-mq-virtio.c new file mode 100644 index 000000000000..c3afbca11299 --- /dev/null +++ b/block/blk-mq-virtio.c @@ -0,0 +1,54 @@ +/* + * 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/device.h> +#include <linux/blk-mq.h> +#include <linux/blk-mq-virtio.h> +#include <linux/virtio_config.h> +#include <linux/module.h> +#include "blk-mq.h" + +/** + * blk_mq_virtio_map_queues - provide a default queue mapping for virtio device + * @set: tagset to provide the mapping for + * @vdev: virtio device associated with @set. + * @first_vec: first interrupt vectors to use for queues (usually 0) + * + * This function assumes the virtio device @vdev 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_virtio_map_queues(struct blk_mq_tag_set *set, + struct virtio_device *vdev, int first_vec) +{ + const struct cpumask *mask; + unsigned int queue, cpu; + + if (!vdev->config->get_vq_affinity) + goto fallback; + + for (queue = 0; queue < set->nr_hw_queues; queue++) { + mask = vdev->config->get_vq_affinity(vdev, first_vec + queue); + if (!mask) + goto fallback; + + for_each_cpu(cpu, mask) + set->mq_map[cpu] = queue; + } + + return 0; +fallback: + return blk_mq_map_queues(set); +} +EXPORT_SYMBOL_GPL(blk_mq_virtio_map_queues); |