Message ID | 20190823001528.5673-6-damien.lemoal@wdc.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Elevator cleanups and improvements | expand |
On 23/08/2019 02:15, Damien Le Moal wrote: > Introduce the elevator feature ELEVATOR_F_ZONED_BLOCK_DEV to indicate > that an elevator supports zoned block device write ordering control. > > Mark the mq-deadline as supporting this feature which is implemented > using zone write locking. SCSI zoned block device scan and null_blk > device creation with zoned mode enabled are also modified to require > this feature using the helper blk_queue_required_elevator_features(). > > This requirement can always be satisfied as the mq-deadline scheduler is > always selected for in-kernel compilation when CONFIG_BLK_DEV_ZONED > (zoned block device support) is enabled. Hmm I would have preferred this to be split into two patches, one introducing the features (not just ELEVATOR_F_ZONED_BLOCK_DEV but also the features you describe in 4/7) and mark all schedulers with the feature bits and then one pulling the requirement of ELEVATOR_F_ZONED_BLOCK_DEV in null_blk and sd.
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index 2a2a2e82832e..95e03408f2ac 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -795,6 +795,7 @@ static struct elevator_type mq_deadline = { .elevator_attrs = deadline_attrs, .elevator_name = "mq-deadline", .elevator_alias = "deadline", + .elevator_features = ELEVATOR_F_ZONED_BLOCK_DEV, .elevator_owner = THIS_MODULE, }; MODULE_ALIAS("mq-deadline-iosched"); diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c index 99c56d72ff78..253bb7b4443e 100644 --- a/drivers/block/null_blk_main.c +++ b/drivers/block/null_blk_main.c @@ -1538,6 +1538,9 @@ static int null_gendisk_register(struct nullb *nullb) if (ret != 0) return ret; + + blk_queue_required_elevator_features(disk->queue, + ELEVATOR_F_ZONED_BLOCK_DEV); } add_disk(disk); @@ -1691,6 +1694,8 @@ static int null_add_dev(struct nullb_device *dev) blk_queue_chunk_sectors(nullb->q, dev->zone_size_sects); nullb->q->limits.zoned = BLK_ZONED_HM; blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, nullb->q); + blk_queue_required_elevator_features(nullb->q, + ELEVATOR_F_ZONED_BLOCK_DEV); } nullb->q->queuedata = nullb; diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 367614f0e34f..983f5d0be902 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -490,6 +490,8 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, unsigned char *buf) goto err; /* The drive satisfies the kernel restrictions: set it up */ + blk_queue_required_elevator_features(sdkp->disk->queue, + ELEVATOR_F_ZONED_BLOCK_DEV); blk_queue_chunk_sectors(sdkp->disk->queue, logical_to_sectors(sdkp->device, zone_blocks)); blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, sdkp->disk->queue); diff --git a/include/linux/elevator.h b/include/linux/elevator.h index a99ca9979d71..2b667cb23fc0 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -166,5 +166,12 @@ extern struct request *elv_rb_find(struct rb_root *, sector_t); #define rq_entry_fifo(ptr) list_entry((ptr), struct request, queuelist) #define rq_fifo_clear(rq) list_del_init(&(rq)->queuelist) +/* + * Elevator features. + */ + +/* Supports zoned block devices sequential write */ +#define ELEVATOR_F_ZONED_BLOCK_DEV (1UL << 0) + #endif /* CONFIG_BLOCK */ #endif
Introduce the elevator feature ELEVATOR_F_ZONED_BLOCK_DEV to indicate that an elevator supports zoned block device write ordering control. Mark the mq-deadline as supporting this feature which is implemented using zone write locking. SCSI zoned block device scan and null_blk device creation with zoned mode enabled are also modified to require this feature using the helper blk_queue_required_elevator_features(). This requirement can always be satisfied as the mq-deadline scheduler is always selected for in-kernel compilation when CONFIG_BLK_DEV_ZONED (zoned block device support) is enabled. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> --- block/mq-deadline.c | 1 + drivers/block/null_blk_main.c | 5 +++++ drivers/scsi/sd_zbc.c | 2 ++ include/linux/elevator.h | 7 +++++++ 4 files changed, 15 insertions(+)