[v4,08/10] null_blk: Support REQ_OP_ZONE_APPEND
diff mbox series

Message ID 20200403101250.33245-9-johannes.thumshirn@wdc.com
State New
Headers show
Series
  • Introduce Zone Append for writing to zoned block devices
Related show

Commit Message

Johannes Thumshirn April 3, 2020, 10:12 a.m. UTC
From: Damien Le Moal <damien.lemoal@wdc.com>

Support REQ_OP_ZONE_APPEND requests for null_blk devices with zoned
mode enabled. Use the internally tracked zone write pointer position
as the actual write position and return it using the command request
__sector field in the case of an mq device and using the command BIO
sector in the case of a BIO device.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
---
 drivers/block/null_blk_zoned.c | 39 +++++++++++++++++++++++++++-------
 1 file changed, 31 insertions(+), 8 deletions(-)

Comments

Christoph Hellwig April 7, 2020, 5:05 p.m. UTC | #1
On Fri, Apr 03, 2020 at 07:12:48PM +0900, Johannes Thumshirn wrote:
> From: Damien Le Moal <damien.lemoal@wdc.com>
> 
> Support REQ_OP_ZONE_APPEND requests for null_blk devices with zoned
> mode enabled. Use the internally tracked zone write pointer position
> as the actual write position and return it using the command request
> __sector field in the case of an mq device and using the command BIO
> sector in the case of a BIO device.
> 
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Patch
diff mbox series

diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c
index c60b19432a2e..b664be0bbb5e 100644
--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -67,13 +67,22 @@  int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
 
 int null_register_zoned_dev(struct nullb *nullb)
 {
+	struct nullb_device *dev = nullb->dev;
 	struct request_queue *q = nullb->q;
 
-	if (queue_is_mq(q))
-		return blk_revalidate_disk_zones(nullb->disk);
+	if (queue_is_mq(q)) {
+		int ret = blk_revalidate_disk_zones(nullb->disk);
+
+		if (ret)
+			return ret;
+	} else {
+		blk_queue_chunk_sectors(q, dev->zone_size_sects);
+		q->nr_zones = blkdev_nr_zones(nullb->disk);
+	}
 
-	blk_queue_chunk_sectors(q, nullb->dev->zone_size_sects);
-	q->nr_zones = blkdev_nr_zones(nullb->disk);
+	blk_queue_max_zone_append_sectors(q,
+			min_t(sector_t, q->limits.max_hw_sectors,
+			      dev->zone_size_sects));
 
 	return 0;
 }
@@ -133,7 +142,7 @@  size_t null_zone_valid_read_len(struct nullb *nullb,
 }
 
 static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
-		     unsigned int nr_sectors)
+				    unsigned int nr_sectors, bool append)
 {
 	struct nullb_device *dev = cmd->nq->dev;
 	unsigned int zno = null_zone_no(dev, sector);
@@ -151,9 +160,21 @@  static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 	case BLK_ZONE_COND_IMP_OPEN:
 	case BLK_ZONE_COND_EXP_OPEN:
 	case BLK_ZONE_COND_CLOSED:
-		/* Writes must be at the write pointer position */
-		if (sector != zone->wp)
+		/*
+		 * Regular writes must be at the write pointer position.
+		 * Zone append writes are automatically issued at the write
+		 * pointer and the position returned using the request or BIO
+		 * sector.
+		 */
+		if (append) {
+			sector = zone->wp;
+			if (cmd->bio)
+				cmd->bio->bi_iter.bi_sector = sector;
+			else
+				cmd->rq->__sector = sector;
+		} else if (sector != zone->wp) {
 			return BLK_STS_IOERR;
+		}
 
 		if (zone->cond != BLK_ZONE_COND_EXP_OPEN)
 			zone->cond = BLK_ZONE_COND_IMP_OPEN;
@@ -232,7 +253,9 @@  blk_status_t null_handle_zoned(struct nullb_cmd *cmd, enum req_opf op,
 {
 	switch (op) {
 	case REQ_OP_WRITE:
-		return null_zone_write(cmd, sector, nr_sectors);
+		return null_zone_write(cmd, sector, nr_sectors, false);
+	case REQ_OP_ZONE_APPEND:
+		return null_zone_write(cmd, sector, nr_sectors, true);
 	case REQ_OP_ZONE_RESET:
 	case REQ_OP_ZONE_RESET_ALL:
 	case REQ_OP_ZONE_OPEN: