diff options
| -rw-r--r-- | drivers/block/null_blk/main.c | 102 | ||||
| -rw-r--r-- | drivers/block/null_blk/null_blk.h | 2 |
2 files changed, 87 insertions, 17 deletions
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index f4af95c2f9a9..323af5c9c802 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -328,30 +328,69 @@ nullb_device_##NAME##_store(struct config_item *item, const char *page, \ } \ CONFIGFS_ATTR(nullb_device_, NAME); -static int nullb_apply_submit_queues(struct nullb_device *dev, - unsigned int submit_queues) +static int nullb_update_nr_hw_queues(struct nullb_device *dev, + unsigned int submit_queues, + unsigned int poll_queues) + { - struct nullb *nullb = dev->nullb; struct blk_mq_tag_set *set; + int ret, nr_hw_queues; - if (!nullb) + if (!dev->nullb) return 0; /* + * Make sure at least one queue exists for each of submit and poll. + */ + if (!submit_queues || !poll_queues) + return -EINVAL; + + /* * Make sure that null_init_hctx() does not access nullb->queues[] past * the end of that array. */ - if (submit_queues > nr_cpu_ids) + if (submit_queues > nr_cpu_ids || poll_queues > g_poll_queues) return -EINVAL; - set = nullb->tag_set; - blk_mq_update_nr_hw_queues(set, submit_queues); - return set->nr_hw_queues == submit_queues ? 0 : -ENOMEM; + + /* + * Keep previous and new queue numbers in nullb_device for reference in + * the call back function null_map_queues(). + */ + dev->prev_submit_queues = dev->submit_queues; + dev->prev_poll_queues = dev->poll_queues; + dev->submit_queues = submit_queues; + dev->poll_queues = poll_queues; + + set = dev->nullb->tag_set; + nr_hw_queues = submit_queues + poll_queues; + blk_mq_update_nr_hw_queues(set, nr_hw_queues); + ret = set->nr_hw_queues == nr_hw_queues ? 0 : -ENOMEM; + + if (ret) { + /* on error, revert the queue numbers */ + dev->submit_queues = dev->prev_submit_queues; + dev->poll_queues = dev->prev_poll_queues; + } + + return ret; +} + +static int nullb_apply_submit_queues(struct nullb_device *dev, + unsigned int submit_queues) +{ + return nullb_update_nr_hw_queues(dev, submit_queues, dev->poll_queues); +} + +static int nullb_apply_poll_queues(struct nullb_device *dev, + unsigned int poll_queues) +{ + return nullb_update_nr_hw_queues(dev, dev->submit_queues, poll_queues); } NULLB_DEVICE_ATTR(size, ulong, NULL); NULLB_DEVICE_ATTR(completion_nsec, ulong, NULL); NULLB_DEVICE_ATTR(submit_queues, uint, nullb_apply_submit_queues); -NULLB_DEVICE_ATTR(poll_queues, uint, nullb_apply_submit_queues); +NULLB_DEVICE_ATTR(poll_queues, uint, nullb_apply_poll_queues); NULLB_DEVICE_ATTR(home_node, uint, NULL); NULLB_DEVICE_ATTR(queue_mode, uint, NULL); NULLB_DEVICE_ATTR(blocksize, uint, NULL); @@ -599,7 +638,9 @@ static struct nullb_device *null_alloc_dev(void) dev->size = g_gb * 1024; dev->completion_nsec = g_completion_nsec; dev->submit_queues = g_submit_queues; + dev->prev_submit_queues = g_submit_queues; dev->poll_queues = g_poll_queues; + dev->prev_poll_queues = g_poll_queues; dev->home_node = g_home_node; dev->queue_mode = g_queue_mode; dev->blocksize = g_bs; @@ -1465,25 +1506,45 @@ static int null_map_queues(struct blk_mq_tag_set *set) { struct nullb *nullb = set->driver_data; int i, qoff; + unsigned int submit_queues = g_submit_queues; + unsigned int poll_queues = g_poll_queues; + + if (nullb) { + struct nullb_device *dev = nullb->dev; + + /* + * Refer nr_hw_queues of the tag set to check if the expected + * number of hardware queues are prepared. If block layer failed + * to prepare them, use previous numbers of submit queues and + * poll queues to map queues. + */ + if (set->nr_hw_queues == + dev->submit_queues + dev->poll_queues) { + submit_queues = dev->submit_queues; + poll_queues = dev->poll_queues; + } else if (set->nr_hw_queues == + dev->prev_submit_queues + dev->prev_poll_queues) { + submit_queues = dev->prev_submit_queues; + poll_queues = dev->prev_poll_queues; + } else { + pr_warn("tag set has unexpected nr_hw_queues: %d\n", + set->nr_hw_queues); + return -EINVAL; + } + } for (i = 0, qoff = 0; i < set->nr_maps; i++) { struct blk_mq_queue_map *map = &set->map[i]; switch (i) { case HCTX_TYPE_DEFAULT: - if (nullb) - map->nr_queues = nullb->dev->submit_queues; - else - map->nr_queues = g_submit_queues; + map->nr_queues = submit_queues; break; case HCTX_TYPE_READ: map->nr_queues = 0; continue; case HCTX_TYPE_POLL: - if (nullb) - map->nr_queues = nullb->dev->poll_queues; - else - map->nr_queues = g_poll_queues; + map->nr_queues = poll_queues; break; } map->queue_offset = qoff; @@ -1853,6 +1914,13 @@ static int null_validate_conf(struct nullb_device *dev) dev->submit_queues = nr_cpu_ids; else if (dev->submit_queues == 0) dev->submit_queues = 1; + dev->prev_submit_queues = dev->submit_queues; + + if (dev->poll_queues > g_poll_queues) + dev->poll_queues = g_poll_queues; + else if (dev->poll_queues == 0) + dev->poll_queues = 1; + dev->prev_poll_queues = dev->poll_queues; dev->queue_mode = min_t(unsigned int, dev->queue_mode, NULL_Q_MQ); dev->irqmode = min_t(unsigned int, dev->irqmode, NULL_IRQ_TIMER); diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h index 90c3eefb3ca3..78eb56b0ca55 100644 --- a/drivers/block/null_blk/null_blk.h +++ b/drivers/block/null_blk/null_blk.h @@ -86,7 +86,9 @@ struct nullb_device { unsigned int zone_max_open; /* max number of open zones */ unsigned int zone_max_active; /* max number of active zones */ unsigned int submit_queues; /* number of submission queues */ + unsigned int prev_submit_queues; /* number of submission queues before change */ unsigned int poll_queues; /* number of IOPOLL submission queues */ + unsigned int prev_poll_queues; /* number of IOPOLL submission queues before change */ unsigned int home_node; /* home node for the device */ unsigned int queue_mode; /* block interface */ unsigned int blocksize; /* block size */ |