diff options
Diffstat (limited to 'block/genhd.c')
| -rw-r--r-- | block/genhd.c | 266 |
1 files changed, 163 insertions, 103 deletions
diff --git a/block/genhd.c b/block/genhd.c index c2bd86cd09de..8171a6bc3210 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -125,37 +125,46 @@ static void part_stat_read_all(struct block_device *part, } } -unsigned int part_in_flight(struct block_device *part) +static void bdev_count_inflight_rw(struct block_device *part, + unsigned int inflight[2], bool mq_driver) { - unsigned int inflight = 0; int cpu; - for_each_possible_cpu(cpu) { - inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) + - part_stat_local_read_cpu(part, in_flight[1], cpu); + if (mq_driver) { + blk_mq_in_driver_rw(part, inflight); + } else { + for_each_possible_cpu(cpu) { + inflight[READ] += part_stat_local_read_cpu( + part, in_flight[READ], cpu); + inflight[WRITE] += part_stat_local_read_cpu( + part, in_flight[WRITE], cpu); + } } - if ((int)inflight < 0) - inflight = 0; - return inflight; + if (WARN_ON_ONCE((int)inflight[READ] < 0)) + inflight[READ] = 0; + if (WARN_ON_ONCE((int)inflight[WRITE] < 0)) + inflight[WRITE] = 0; } -static void part_in_flight_rw(struct block_device *part, - unsigned int inflight[2]) +/** + * bdev_count_inflight - get the number of inflight IOs for a block device. + * + * @part: the block device. + * + * Inflight here means started IO accounting, from bdev_start_io_acct() for + * bio-based block device, and from blk_account_io_start() for rq-based block + * device. + */ +unsigned int bdev_count_inflight(struct block_device *part) { - int cpu; + unsigned int inflight[2] = {0}; - inflight[0] = 0; - inflight[1] = 0; - for_each_possible_cpu(cpu) { - inflight[0] += part_stat_local_read_cpu(part, in_flight[0], cpu); - inflight[1] += part_stat_local_read_cpu(part, in_flight[1], cpu); - } - if ((int)inflight[0] < 0) - inflight[0] = 0; - if ((int)inflight[1] < 0) - inflight[1] = 0; + bdev_count_inflight_rw(part, inflight, false); + + return inflight[READ] + inflight[WRITE]; } +EXPORT_SYMBOL_GPL(bdev_count_inflight); /* * Can be deleted altogether. Later. @@ -389,19 +398,35 @@ int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode) return ret; } -/** - * add_disk_fwnode - add disk information to kernel list with fwnode - * @parent: parent device for the disk - * @disk: per-device partitioning information - * @groups: Additional per-device sysfs groups - * @fwnode: attached disk fwnode - * - * This function registers the partitioning information in @disk - * with the kernel. Also attach a fwnode to the disk device. - */ -int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, - const struct attribute_group **groups, - struct fwnode_handle *fwnode) +static void add_disk_final(struct gendisk *disk) +{ + struct device *ddev = disk_to_dev(disk); + + if (!(disk->flags & GENHD_FL_HIDDEN)) { + /* Make sure the first partition scan will be proceed */ + if (get_capacity(disk) && disk_has_partscan(disk)) + set_bit(GD_NEED_PART_SCAN, &disk->state); + + bdev_add(disk->part0, ddev->devt); + if (get_capacity(disk)) + disk_scan_partitions(disk, BLK_OPEN_READ); + + /* + * Announce the disk and partitions after all partitions are + * created. (for hidden disks uevents remain suppressed forever) + */ + dev_set_uevent_suppress(ddev, 0); + disk_uevent(disk, KOBJ_ADD); + } + + blk_apply_bdi_limits(disk->bdi, &disk->queue->limits); + disk_add_events(disk); + set_bit(GD_ADDED, &disk->state); +} + +static int __add_disk(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups, + struct fwnode_handle *fwnode) { struct device *ddev = disk_to_dev(disk); @@ -416,12 +441,6 @@ int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, */ if (disk->fops->submit_bio || disk->fops->poll_bio) return -EINVAL; - - /* - * Initialize the I/O scheduler code and pick a default one if - * needed. - */ - elevator_init_mq(disk->queue); } else { if (!disk->fops->submit_bio) return -EINVAL; @@ -438,7 +457,7 @@ int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, ret = -EINVAL; if (disk->major) { if (WARN_ON(!disk->minors)) - goto out_exit_elevator; + goto out; if (disk->minors > DISK_MAX_PARTS) { pr_err("block: can't allocate more than %d partitions\n", @@ -448,14 +467,14 @@ int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, if (disk->first_minor > MINORMASK || disk->minors > MINORMASK + 1 || disk->first_minor + disk->minors > MINORMASK + 1) - goto out_exit_elevator; + goto out; } else { if (WARN_ON(disk->minors)) - goto out_exit_elevator; + goto out; ret = blk_alloc_ext_minor(); if (ret < 0) - goto out_exit_elevator; + goto out; disk->major = BLOCK_EXT_MAJOR; disk->first_minor = ret; } @@ -516,21 +535,6 @@ int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, &disk->bdi->dev->kobj, "bdi"); if (ret) goto out_unregister_bdi; - - /* Make sure the first partition scan will be proceed */ - if (get_capacity(disk) && disk_has_partscan(disk)) - set_bit(GD_NEED_PART_SCAN, &disk->state); - - bdev_add(disk->part0, ddev->devt); - if (get_capacity(disk)) - disk_scan_partitions(disk, BLK_OPEN_READ); - - /* - * Announce the disk and partitions after all partitions are - * created. (for hidden disks uevents remain suppressed forever) - */ - dev_set_uevent_suppress(ddev, 0); - disk_uevent(disk, KOBJ_ADD); } else { /* * Even if the block_device for a hidden gendisk is not @@ -539,10 +543,6 @@ int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, */ disk->part0->bd_dev = MKDEV(disk->major, disk->first_minor); } - - blk_apply_bdi_limits(disk->bdi, &disk->queue->limits); - disk_add_events(disk); - set_bit(GD_ADDED, &disk->state); return 0; out_unregister_bdi: @@ -564,12 +564,46 @@ out_device_del: out_free_ext_minor: if (disk->major == BLOCK_EXT_MAJOR) blk_free_ext_minor(disk->first_minor); -out_exit_elevator: - if (disk->queue->elevator) { - mutex_lock(&disk->queue->elevator_lock); - elevator_exit(disk->queue); - mutex_unlock(&disk->queue->elevator_lock); +out: + return ret; +} + +/** + * add_disk_fwnode - add disk information to kernel list with fwnode + * @parent: parent device for the disk + * @disk: per-device partitioning information + * @groups: Additional per-device sysfs groups + * @fwnode: attached disk fwnode + * + * This function registers the partitioning information in @disk + * with the kernel. Also attach a fwnode to the disk device. + */ +int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups, + struct fwnode_handle *fwnode) +{ + struct blk_mq_tag_set *set; + unsigned int memflags; + int ret; + + if (queue_is_mq(disk->queue)) { + set = disk->queue->tag_set; + memflags = memalloc_noio_save(); + down_read(&set->update_nr_hwq_lock); + ret = __add_disk(parent, disk, groups, fwnode); + up_read(&set->update_nr_hwq_lock); + memalloc_noio_restore(memflags); + } else { + ret = __add_disk(parent, disk, groups, fwnode); } + + /* + * add_disk_final() needn't to read `nr_hw_queues`, so move it out + * of read lock `set->update_nr_hwq_lock` for avoiding unnecessary + * lock dependency on `disk->open_mutex` from scanning partition. + */ + if (!ret) + add_disk_final(disk); return ret; } EXPORT_SYMBOL_GPL(add_disk_fwnode); @@ -652,26 +686,7 @@ void blk_mark_disk_dead(struct gendisk *disk) } EXPORT_SYMBOL_GPL(blk_mark_disk_dead); -/** - * del_gendisk - remove the gendisk - * @disk: the struct gendisk to remove - * - * Removes the gendisk and all its associated resources. This deletes the - * partitions associated with the gendisk, and unregisters the associated - * request_queue. - * - * This is the counter to the respective __device_add_disk() call. - * - * The final removal of the struct gendisk happens when its refcount reaches 0 - * with put_disk(), which should be called after del_gendisk(), if - * __device_add_disk() was used. - * - * Drivers exist which depend on the release of the gendisk to be synchronous, - * it should not be deferred. - * - * Context: can sleep - */ -void del_gendisk(struct gendisk *disk) +static void __del_gendisk(struct gendisk *disk) { struct request_queue *q = disk->queue; struct block_device *part; @@ -743,14 +758,7 @@ void del_gendisk(struct gendisk *disk) if (queue_is_mq(q)) blk_mq_cancel_work_sync(q); - blk_mq_quiesce_queue(q); - if (q->elevator) { - mutex_lock(&q->elevator_lock); - elevator_exit(q); - mutex_unlock(&q->elevator_lock); - } rq_qos_exit(q); - blk_mq_unquiesce_queue(q); /* * If the disk does not own the queue, allow using passthrough requests @@ -764,6 +772,55 @@ void del_gendisk(struct gendisk *disk) if (start_drain) blk_unfreeze_release_lock(q); } + +static void disable_elv_switch(struct request_queue *q) +{ + struct blk_mq_tag_set *set = q->tag_set; + WARN_ON_ONCE(!queue_is_mq(q)); + + down_write(&set->update_nr_hwq_lock); + blk_queue_flag_set(QUEUE_FLAG_NO_ELV_SWITCH, q); + up_write(&set->update_nr_hwq_lock); +} + +/** + * del_gendisk - remove the gendisk + * @disk: the struct gendisk to remove + * + * Removes the gendisk and all its associated resources. This deletes the + * partitions associated with the gendisk, and unregisters the associated + * request_queue. + * + * This is the counter to the respective __device_add_disk() call. + * + * The final removal of the struct gendisk happens when its refcount reaches 0 + * with put_disk(), which should be called after del_gendisk(), if + * __device_add_disk() was used. + * + * Drivers exist which depend on the release of the gendisk to be synchronous, + * it should not be deferred. + * + * Context: can sleep + */ +void del_gendisk(struct gendisk *disk) +{ + struct blk_mq_tag_set *set; + unsigned int memflags; + + if (!queue_is_mq(disk->queue)) { + __del_gendisk(disk); + } else { + set = disk->queue->tag_set; + + disable_elv_switch(disk->queue); + + memflags = memalloc_noio_save(); + down_read(&set->update_nr_hwq_lock); + __del_gendisk(disk); + up_read(&set->update_nr_hwq_lock); + memalloc_noio_restore(memflags); + } +} EXPORT_SYMBOL(del_gendisk); /** @@ -1005,7 +1062,7 @@ ssize_t part_stat_show(struct device *dev, struct disk_stats stat; unsigned int inflight; - inflight = part_in_flight(bdev); + inflight = bdev_count_inflight(bdev); if (inflight) { part_stat_lock(); update_io_ticks(bdev, jiffies, true); @@ -1042,19 +1099,21 @@ ssize_t part_stat_show(struct device *dev, (unsigned int)div_u64(stat.nsecs[STAT_FLUSH], NSEC_PER_MSEC)); } +/* + * Show the number of IOs issued to driver. + * For bio-based device, started from bdev_start_io_acct(); + * For rq-based device, started from blk_mq_start_request(); + */ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr, char *buf) { struct block_device *bdev = dev_to_bdev(dev); struct request_queue *q = bdev_get_queue(bdev); - unsigned int inflight[2]; + unsigned int inflight[2] = {0}; - if (queue_is_mq(q)) - blk_mq_in_flight_rw(q, bdev, inflight); - else - part_in_flight_rw(bdev, inflight); + bdev_count_inflight_rw(bdev, inflight, queue_is_mq(q)); - return sysfs_emit(buf, "%8u %8u\n", inflight[0], inflight[1]); + return sysfs_emit(buf, "%8u %8u\n", inflight[READ], inflight[WRITE]); } static ssize_t disk_capability_show(struct device *dev, @@ -1307,7 +1366,7 @@ static int diskstats_show(struct seq_file *seqf, void *v) if (bdev_is_partition(hd) && !bdev_nr_sectors(hd)) continue; - inflight = part_in_flight(hd); + inflight = bdev_count_inflight(hd); if (inflight) { part_stat_lock(); update_io_ticks(hd, jiffies, true); @@ -1422,6 +1481,7 @@ struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, #ifdef CONFIG_BLOCK_HOLDER_DEPRECATED INIT_LIST_HEAD(&disk->slave_bdevs); #endif + mutex_init(&disk->rqos_state_mutex); return disk; out_erase_part0: |