From 14509b748ff58df3f0980b1cd70ade0e4a805e99 Mon Sep 17 00:00:00 2001
From: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Date: Tue, 30 Jan 2024 13:21:34 +0900
Subject: null_blk: add configfs variable shared_tags

Allow setting shared_tags through configfs, which could only be set as a
module parameter. For that purpose, delay tag_set initialization from
null_init() to null_add_dev(). Refer tag_set.ops as the flag to check if
tag_set is initialized or not.

The following parameters can not be set through configfs yet:

    timeout
    requeue
    init_hctx

Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240130042134.2463659-1-shinichiro.kawasaki@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c | 38 ++++++++++++++++++++------------------
 1 file changed, 20 insertions(+), 18 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 36755f263e8e..4281371c81fe 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -165,8 +165,8 @@ static bool g_blocking;
 module_param_named(blocking, g_blocking, bool, 0444);
 MODULE_PARM_DESC(blocking, "Register as a blocking blk-mq driver device");
 
-static bool shared_tags;
-module_param(shared_tags, bool, 0444);
+static bool g_shared_tags;
+module_param_named(shared_tags, g_shared_tags, bool, 0444);
 MODULE_PARM_DESC(shared_tags, "Share tag set between devices for blk-mq");
 
 static bool g_shared_tag_bitmap;
@@ -426,6 +426,7 @@ NULLB_DEVICE_ATTR(zone_max_open, uint, NULL);
 NULLB_DEVICE_ATTR(zone_max_active, uint, NULL);
 NULLB_DEVICE_ATTR(virt_boundary, bool, NULL);
 NULLB_DEVICE_ATTR(no_sched, bool, NULL);
+NULLB_DEVICE_ATTR(shared_tags, bool, NULL);
 NULLB_DEVICE_ATTR(shared_tag_bitmap, bool, NULL);
 
 static ssize_t nullb_device_power_show(struct config_item *item, char *page)
@@ -571,6 +572,7 @@ static struct configfs_attribute *nullb_device_attrs[] = {
 	&nullb_device_attr_zone_offline,
 	&nullb_device_attr_virt_boundary,
 	&nullb_device_attr_no_sched,
+	&nullb_device_attr_shared_tags,
 	&nullb_device_attr_shared_tag_bitmap,
 	NULL,
 };
@@ -653,10 +655,11 @@ static ssize_t memb_group_features_show(struct config_item *item, char *page)
 			"badblocks,blocking,blocksize,cache_size,"
 			"completion_nsec,discard,home_node,hw_queue_depth,"
 			"irqmode,max_sectors,mbps,memory_backed,no_sched,"
-			"poll_queues,power,queue_mode,shared_tag_bitmap,size,"
-			"submit_queues,use_per_node_hctx,virt_boundary,zoned,"
-			"zone_capacity,zone_max_active,zone_max_open,"
-			"zone_nr_conv,zone_offline,zone_readonly,zone_size\n");
+			"poll_queues,power,queue_mode,shared_tag_bitmap,"
+			"shared_tags,size,submit_queues,use_per_node_hctx,"
+			"virt_boundary,zoned,zone_capacity,zone_max_active,"
+			"zone_max_open,zone_nr_conv,zone_offline,zone_readonly,"
+			"zone_size\n");
 }
 
 CONFIGFS_ATTR_RO(memb_group_, features);
@@ -738,6 +741,7 @@ static struct nullb_device *null_alloc_dev(void)
 	dev->zone_max_active = g_zone_max_active;
 	dev->virt_boundary = g_virt_boundary;
 	dev->no_sched = g_no_sched;
+	dev->shared_tags = g_shared_tags;
 	dev->shared_tag_bitmap = g_shared_tag_bitmap;
 	return dev;
 }
@@ -2124,7 +2128,14 @@ static int null_add_dev(struct nullb_device *dev)
 		goto out_free_nullb;
 
 	if (dev->queue_mode == NULL_Q_MQ) {
-		if (shared_tags) {
+		if (dev->shared_tags) {
+			if (!tag_set.ops) {
+				rv = null_init_tag_set(NULL, &tag_set);
+				if (rv) {
+					tag_set.ops = NULL;
+					goto out_cleanup_queues;
+				}
+			}
 			nullb->tag_set = &tag_set;
 			rv = 0;
 		} else {
@@ -2311,18 +2322,12 @@ static int __init null_init(void)
 		g_submit_queues = 1;
 	}
 
-	if (g_queue_mode == NULL_Q_MQ && shared_tags) {
-		ret = null_init_tag_set(NULL, &tag_set);
-		if (ret)
-			return ret;
-	}
-
 	config_group_init(&nullb_subsys.su_group);
 	mutex_init(&nullb_subsys.su_mutex);
 
 	ret = configfs_register_subsystem(&nullb_subsys);
 	if (ret)
-		goto err_tagset;
+		return ret;
 
 	mutex_init(&lock);
 
@@ -2349,9 +2354,6 @@ err_dev:
 	unregister_blkdev(null_major, "nullb");
 err_conf:
 	configfs_unregister_subsystem(&nullb_subsys);
-err_tagset:
-	if (g_queue_mode == NULL_Q_MQ && shared_tags)
-		blk_mq_free_tag_set(&tag_set);
 	return ret;
 }
 
@@ -2370,7 +2372,7 @@ static void __exit null_exit(void)
 	}
 	mutex_unlock(&lock);
 
-	if (g_queue_mode == NULL_Q_MQ && shared_tags)
+	if (tag_set.ops)
 		blk_mq_free_tag_set(&tag_set);
 }
 
-- 
cgit v1.2.3


From 27e32cd23fed1ab88098897897dcb9ec2bdba4de Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 13 Feb 2024 08:34:20 +0100
Subject: block: pass a queue_limits argument to blk_mq_alloc_disk

Pass a queue_limits to blk_mq_alloc_disk and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240213073425.1621680-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 arch/um/drivers/ubd_kern.c          | 2 +-
 block/blk-mq.c                      | 5 +++--
 drivers/block/amiflop.c             | 2 +-
 drivers/block/aoe/aoeblk.c          | 2 +-
 drivers/block/ataflop.c             | 2 +-
 drivers/block/floppy.c              | 2 +-
 drivers/block/loop.c                | 2 +-
 drivers/block/mtip32xx/mtip32xx.c   | 2 +-
 drivers/block/nbd.c                 | 2 +-
 drivers/block/null_blk/main.c       | 2 +-
 drivers/block/ps3disk.c             | 2 +-
 drivers/block/rbd.c                 | 2 +-
 drivers/block/rnbd/rnbd-clt.c       | 2 +-
 drivers/block/sunvdc.c              | 2 +-
 drivers/block/swim.c                | 2 +-
 drivers/block/swim3.c               | 2 +-
 drivers/block/ublk_drv.c            | 2 +-
 drivers/block/virtio_blk.c          | 2 +-
 drivers/block/xen-blkfront.c        | 2 +-
 drivers/block/z2ram.c               | 2 +-
 drivers/cdrom/gdrom.c               | 2 +-
 drivers/memstick/core/ms_block.c    | 2 +-
 drivers/memstick/core/mspro_block.c | 2 +-
 drivers/mmc/core/queue.c            | 2 +-
 drivers/mtd/mtd_blkdevs.c           | 2 +-
 drivers/mtd/ubi/block.c             | 2 +-
 drivers/nvme/host/core.c            | 2 +-
 drivers/s390/block/dasd_genhd.c     | 2 +-
 drivers/s390/block/scm_blk.c        | 2 +-
 include/linux/blk-mq.h              | 7 ++++---
 30 files changed, 35 insertions(+), 33 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 92ee2697ff39..25f1b18ce7d4 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -906,7 +906,7 @@ static int ubd_add(int n, char **error_out)
 	if (err)
 		goto out;
 
-	disk = blk_mq_alloc_disk(&ubd_dev->tag_set, ubd_dev);
+	disk = blk_mq_alloc_disk(&ubd_dev->tag_set, NULL, ubd_dev);
 	if (IS_ERR(disk)) {
 		err = PTR_ERR(disk);
 		goto out_cleanup_tags;
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f6499bbd89be..6abb4ce46baa 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -4130,13 +4130,14 @@ void blk_mq_destroy_queue(struct request_queue *q)
 }
 EXPORT_SYMBOL(blk_mq_destroy_queue);
 
-struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata,
+struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set,
+		struct queue_limits *lim, void *queuedata,
 		struct lock_class_key *lkclass)
 {
 	struct request_queue *q;
 	struct gendisk *disk;
 
-	q = blk_mq_alloc_queue(set, NULL, queuedata);
+	q = blk_mq_alloc_queue(set, lim, queuedata);
 	if (IS_ERR(q))
 		return ERR_CAST(q);
 
diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 2b98114a9fe0..a25414228e47 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -1779,7 +1779,7 @@ static int fd_alloc_disk(int drive, int system)
 	struct gendisk *disk;
 	int err;
 
-	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL);
+	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index b1b47d88f5db..2ff6e2da8cc4 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -371,7 +371,7 @@ aoeblk_gdalloc(void *vp)
 		goto err_mempool;
 	}
 
-	gd = blk_mq_alloc_disk(set, d);
+	gd = blk_mq_alloc_disk(set, NULL, d);
 	if (IS_ERR(gd)) {
 		pr_err("aoe: cannot allocate block queue for %ld.%d\n",
 			d->aoemajor, d->aoeminor);
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 50949207798d..cacc4ba942a8 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1994,7 +1994,7 @@ static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
 {
 	struct gendisk *disk;
 
-	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL);
+	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 2ba0ba135951..582cf50c6bf6 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4518,7 +4518,7 @@ static int floppy_alloc_disk(unsigned int drive, unsigned int type)
 {
 	struct gendisk *disk;
 
-	disk = blk_mq_alloc_disk(&tag_sets[drive], NULL);
+	disk = blk_mq_alloc_disk(&tag_sets[drive], NULL, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index f8145499da38..3f855cc79c29 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2025,7 +2025,7 @@ static int loop_add(int i)
 	if (err)
 		goto out_free_idr;
 
-	disk = lo->lo_disk = blk_mq_alloc_disk(&lo->tag_set, lo);
+	disk = lo->lo_disk = blk_mq_alloc_disk(&lo->tag_set, NULL, lo);
 	if (IS_ERR(disk)) {
 		err = PTR_ERR(disk);
 		goto out_cleanup_tags;
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index b200950e8fb5..ac08dea73552 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3431,7 +3431,7 @@ static int mtip_block_initialize(struct driver_data *dd)
 		goto block_queue_alloc_tag_error;
 	}
 
-	dd->disk = blk_mq_alloc_disk(&dd->tags, dd);
+	dd->disk = blk_mq_alloc_disk(&dd->tags, NULL, dd);
 	if (IS_ERR(dd->disk)) {
 		dev_err(&dd->pdev->dev,
 			"Unable to allocate request queue\n");
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 33a8f37bb6a1..30ae3cc12e77 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1823,7 +1823,7 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 	if (err < 0)
 		goto out_free_tags;
 
-	disk = blk_mq_alloc_disk(&nbd->tag_set, NULL);
+	disk = blk_mq_alloc_disk(&nbd->tag_set, NULL, NULL);
 	if (IS_ERR(disk)) {
 		err = PTR_ERR(disk);
 		goto out_free_idr;
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 4281371c81fe..eeb895ec6f34 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -2147,7 +2147,7 @@ static int null_add_dev(struct nullb_device *dev)
 			goto out_cleanup_queues;
 
 		nullb->tag_set->timeout = 5 * HZ;
-		nullb->disk = blk_mq_alloc_disk(nullb->tag_set, nullb);
+		nullb->disk = blk_mq_alloc_disk(nullb->tag_set, NULL, nullb);
 		if (IS_ERR(nullb->disk)) {
 			rv = PTR_ERR(nullb->disk);
 			goto out_cleanup_tags;
diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
index 36d7b36c60c7..dfd3860df4f8 100644
--- a/drivers/block/ps3disk.c
+++ b/drivers/block/ps3disk.c
@@ -431,7 +431,7 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 	if (error)
 		goto fail_teardown;
 
-	gendisk = blk_mq_alloc_disk(&priv->tag_set, dev);
+	gendisk = blk_mq_alloc_disk(&priv->tag_set, NULL, dev);
 	if (IS_ERR(gendisk)) {
 		dev_err(&dev->sbd.core, "%s:%u: blk_mq_alloc_disk failed\n",
 			__func__, __LINE__);
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 00ca8a1d8c46..6b4f1898a722 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -4966,7 +4966,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
 	if (err)
 		return err;
 
-	disk = blk_mq_alloc_disk(&rbd_dev->tag_set, rbd_dev);
+	disk = blk_mq_alloc_disk(&rbd_dev->tag_set, NULL, rbd_dev);
 	if (IS_ERR(disk)) {
 		err = PTR_ERR(disk);
 		goto out_tag_set;
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 4044c369d22a..d51be4f2df61 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1408,7 +1408,7 @@ static int rnbd_client_setup_device(struct rnbd_clt_dev *dev,
 	dev->size = le64_to_cpu(rsp->nsectors) *
 			le16_to_cpu(rsp->logical_block_size);
 
-	dev->gd = blk_mq_alloc_disk(&dev->sess->tag_set, dev);
+	dev->gd = blk_mq_alloc_disk(&dev->sess->tag_set, NULL, dev);
 	if (IS_ERR(dev->gd))
 		return PTR_ERR(dev->gd);
 	dev->queue = dev->gd->queue;
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index 7bf4b48e2282..a1f74dd1eae5 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -824,7 +824,7 @@ static int probe_disk(struct vdc_port *port)
 	if (err)
 		return err;
 
-	g = blk_mq_alloc_disk(&port->tag_set, port);
+	g = blk_mq_alloc_disk(&port->tag_set, NULL, port);
 	if (IS_ERR(g)) {
 		printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 		       port->vio.name);
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index f85b6af414b4..16bdf62067d8 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -820,7 +820,7 @@ static int swim_floppy_init(struct swim_priv *swd)
 			goto exit_put_disks;
 
 		swd->unit[drive].disk =
-			blk_mq_alloc_disk(&swd->unit[drive].tag_set,
+			blk_mq_alloc_disk(&swd->unit[drive].tag_set, NULL,
 					  &swd->unit[drive]);
 		if (IS_ERR(swd->unit[drive].disk)) {
 			blk_mq_free_tag_set(&swd->unit[drive].tag_set);
diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index c2bc85826358..a04756ac778e 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -1210,7 +1210,7 @@ static int swim3_attach(struct macio_dev *mdev,
 	if (rc)
 		goto out_unregister;
 
-	disk = blk_mq_alloc_disk(&fs->tag_set, fs);
+	disk = blk_mq_alloc_disk(&fs->tag_set, NULL, fs);
 	if (IS_ERR(disk)) {
 		rc = PTR_ERR(disk);
 		goto out_free_tag_set;
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 1dfb2e77898b..c5b655270798 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -2222,7 +2222,7 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd)
 		goto out_unlock;
 	}
 
-	disk = blk_mq_alloc_disk(&ub->tag_set, NULL);
+	disk = blk_mq_alloc_disk(&ub->tag_set, NULL, NULL);
 	if (IS_ERR(disk)) {
 		ret = PTR_ERR(disk);
 		goto out_unlock;
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 5bf98fd6a651..a23fce4eca44 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1330,7 +1330,7 @@ static int virtblk_probe(struct virtio_device *vdev)
 	if (err)
 		goto out_free_vq;
 
-	vblk->disk = blk_mq_alloc_disk(&vblk->tag_set, vblk);
+	vblk->disk = blk_mq_alloc_disk(&vblk->tag_set, NULL, vblk);
 	if (IS_ERR(vblk->disk)) {
 		err = PTR_ERR(vblk->disk);
 		goto out_free_tags;
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 434fab306777..4cc2884e7484 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1136,7 +1136,7 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 	if (err)
 		goto out_release_minors;
 
-	gd = blk_mq_alloc_disk(&info->tag_set, info);
+	gd = blk_mq_alloc_disk(&info->tag_set, NULL, info);
 	if (IS_ERR(gd)) {
 		err = PTR_ERR(gd);
 		goto out_free_tag_set;
diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index 11493167b0a8..7c5f4e4d9b50 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -318,7 +318,7 @@ static int z2ram_register_disk(int minor)
 	struct gendisk *disk;
 	int err;
 
-	disk = blk_mq_alloc_disk(&tag_set, NULL);
+	disk = blk_mq_alloc_disk(&tag_set, NULL, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
index d668b174ace9..1d044779f5e4 100644
--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -778,7 +778,7 @@ static int probe_gdrom(struct platform_device *devptr)
 	if (err)
 		goto probe_fail_free_cd_info;
 
-	gd.disk = blk_mq_alloc_disk(&gd.tag_set, NULL);
+	gd.disk = blk_mq_alloc_disk(&gd.tag_set, NULL, NULL);
 	if (IS_ERR(gd.disk)) {
 		err = PTR_ERR(gd.disk);
 		goto probe_fail_free_tag_set;
diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c
index 04115cd92433..d3277c901d16 100644
--- a/drivers/memstick/core/ms_block.c
+++ b/drivers/memstick/core/ms_block.c
@@ -2093,7 +2093,7 @@ static int msb_init_disk(struct memstick_dev *card)
 	if (rc)
 		goto out_release_id;
 
-	msb->disk = blk_mq_alloc_disk(&msb->tag_set, card);
+	msb->disk = blk_mq_alloc_disk(&msb->tag_set, NULL, card);
 	if (IS_ERR(msb->disk)) {
 		rc = PTR_ERR(msb->disk);
 		goto out_free_tag_set;
diff --git a/drivers/memstick/core/mspro_block.c b/drivers/memstick/core/mspro_block.c
index 5a69ed33999b..db0e2a42ca3c 100644
--- a/drivers/memstick/core/mspro_block.c
+++ b/drivers/memstick/core/mspro_block.c
@@ -1138,7 +1138,7 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 	if (rc)
 		goto out_release_id;
 
-	msb->disk = blk_mq_alloc_disk(&msb->tag_set, card);
+	msb->disk = blk_mq_alloc_disk(&msb->tag_set, NULL, card);
 	if (IS_ERR(msb->disk)) {
 		rc = PTR_ERR(msb->disk);
 		goto out_free_tag_set;
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index a0a2412f62a7..67ad186d132a 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -447,7 +447,7 @@ struct gendisk *mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
 		return ERR_PTR(ret);
 		
 
-	disk = blk_mq_alloc_disk(&mq->tag_set, mq);
+	disk = blk_mq_alloc_disk(&mq->tag_set, NULL, mq);
 	if (IS_ERR(disk)) {
 		blk_mq_free_tag_set(&mq->tag_set);
 		return disk;
diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index f0526dcc2162..b8878a2457af 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -333,7 +333,7 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 		goto out_kfree_tag_set;
 
 	/* Create gendisk */
-	gd = blk_mq_alloc_disk(new->tag_set, new);
+	gd = blk_mq_alloc_disk(new->tag_set, NULL, new);
 	if (IS_ERR(gd)) {
 		ret = PTR_ERR(gd);
 		goto out_free_tag_set;
diff --git a/drivers/mtd/ubi/block.c b/drivers/mtd/ubi/block.c
index 654bd7372cd8..9be87c231a2e 100644
--- a/drivers/mtd/ubi/block.c
+++ b/drivers/mtd/ubi/block.c
@@ -393,7 +393,7 @@ int ubiblock_create(struct ubi_volume_info *vi)
 
 
 	/* Initialize the gendisk of this ubiblock device */
-	gd = blk_mq_alloc_disk(&dev->tag_set, dev);
+	gd = blk_mq_alloc_disk(&dev->tag_set, NULL, dev);
 	if (IS_ERR(gd)) {
 		ret = PTR_ERR(gd);
 		goto out_free_tags;
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 5bcdf3654598..eed3e22e24d9 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3694,7 +3694,7 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, struct nvme_ns_info *info)
 	if (!ns)
 		return;
 
-	disk = blk_mq_alloc_disk(ctrl->tagset, ns);
+	disk = blk_mq_alloc_disk(ctrl->tagset, NULL, ns);
 	if (IS_ERR(disk))
 		goto out_free_ns;
 	disk->fops = &nvme_bdev_ops;
diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index 30e8ee583e98..0465b706745f 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -53,7 +53,7 @@ int dasd_gendisk_alloc(struct dasd_block *block)
 	if (rc)
 		return rc;
 
-	gdp = blk_mq_alloc_disk(&block->tag_set, block);
+	gdp = blk_mq_alloc_disk(&block->tag_set, NULL, block);
 	if (IS_ERR(gdp)) {
 		blk_mq_free_tag_set(&block->tag_set);
 		return PTR_ERR(gdp);
diff --git a/drivers/s390/block/scm_blk.c b/drivers/s390/block/scm_blk.c
index ade95e91b3c8..d05b2e2799a4 100644
--- a/drivers/s390/block/scm_blk.c
+++ b/drivers/s390/block/scm_blk.c
@@ -462,7 +462,7 @@ int scm_blk_dev_setup(struct scm_blk_dev *bdev, struct scm_device *scmdev)
 	if (ret)
 		goto out;
 
-	bdev->gendisk = blk_mq_alloc_disk(&bdev->tag_set, scmdev);
+	bdev->gendisk = blk_mq_alloc_disk(&bdev->tag_set, NULL, scmdev);
 	if (IS_ERR(bdev->gendisk)) {
 		ret = PTR_ERR(bdev->gendisk);
 		goto out_tag;
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 7d42c359e2ab..390d35fa0032 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -682,13 +682,14 @@ enum {
 
 #define BLK_MQ_NO_HCTX_IDX	(-1U)
 
-struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set, void *queuedata,
+struct gendisk *__blk_mq_alloc_disk(struct blk_mq_tag_set *set,
+		struct queue_limits *lim, void *queuedata,
 		struct lock_class_key *lkclass);
-#define blk_mq_alloc_disk(set, queuedata)				\
+#define blk_mq_alloc_disk(set, lim, queuedata)				\
 ({									\
 	static struct lock_class_key __key;				\
 									\
-	__blk_mq_alloc_disk(set, queuedata, &__key);			\
+	__blk_mq_alloc_disk(set, lim, queuedata, &__key);		\
 })
 struct gendisk *blk_mq_alloc_disk_for_queue(struct request_queue *q,
 		struct lock_class_key *lkclass);
-- 
cgit v1.2.3


From 74fa8f9c553f7b5ccab7d103acae63cc2e080465 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Thu, 15 Feb 2024 08:10:47 +0100
Subject: block: pass a queue_limits argument to blk_alloc_disk

Pass a queue_limits to blk_alloc_disk and apply it if non-NULL.  This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Also change blk_alloc_disk to return an ERR_PTR instead of just NULL
which can't distinguish errors.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 arch/m68k/emu/nfblock.c             |  6 ++++--
 arch/xtensa/platforms/iss/simdisk.c |  8 +++++---
 block/genhd.c                       | 11 ++++++-----
 drivers/block/brd.c                 |  7 ++++---
 drivers/block/drbd/drbd_main.c      |  6 ++++--
 drivers/block/n64cart.c             |  6 ++++--
 drivers/block/null_blk/main.c       |  7 ++++---
 drivers/block/pktcdvd.c             |  7 ++++---
 drivers/block/ps3vram.c             |  6 +++---
 drivers/block/zram/zram_drv.c       |  6 +++---
 drivers/md/bcache/super.c           |  4 ++--
 drivers/md/dm.c                     |  4 ++--
 drivers/md/md.c                     |  7 ++++---
 drivers/nvdimm/btt.c                |  8 ++++----
 drivers/nvdimm/pmem.c               |  6 +++---
 drivers/nvme/host/multipath.c       |  6 +++---
 drivers/s390/block/dcssblk.c        |  6 +++---
 include/linux/blkdev.h              | 10 +++++++---
 18 files changed, 69 insertions(+), 52 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/arch/m68k/emu/nfblock.c b/arch/m68k/emu/nfblock.c
index a708fbd5a844..539ff56b6968 100644
--- a/arch/m68k/emu/nfblock.c
+++ b/arch/m68k/emu/nfblock.c
@@ -117,9 +117,11 @@ static int __init nfhd_init_one(int id, u32 blocks, u32 bsize)
 	dev->bsize = bsize;
 	dev->bshift = ffs(bsize) - 10;
 
-	dev->disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!dev->disk)
+	dev->disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(dev->disk)) {
+		err = PTR_ERR(dev->disk);
 		goto free_dev;
+	}
 
 	dev->disk->major = major_num;
 	dev->disk->first_minor = dev_id * 16;
diff --git a/arch/xtensa/platforms/iss/simdisk.c b/arch/xtensa/platforms/iss/simdisk.c
index 178cf96ca10a..defc67909a9c 100644
--- a/arch/xtensa/platforms/iss/simdisk.c
+++ b/arch/xtensa/platforms/iss/simdisk.c
@@ -264,16 +264,18 @@ static int __init simdisk_setup(struct simdisk *dev, int which,
 		struct proc_dir_entry *procdir)
 {
 	char tmp[2] = { '0' + which, 0 };
-	int err = -ENOMEM;
+	int err;
 
 	dev->fd = -1;
 	dev->filename = NULL;
 	spin_lock_init(&dev->lock);
 	dev->users = 0;
 
-	dev->gd = blk_alloc_disk(NUMA_NO_NODE);
-	if (!dev->gd)
+	dev->gd = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(dev->gd)) {
+		err = PTR_ERR(dev->gd);
 		goto out;
+	}
 	dev->gd->major = simdisk_major;
 	dev->gd->first_minor = which;
 	dev->gd->minors = SIMDISK_MINORS;
diff --git a/block/genhd.c b/block/genhd.c
index 7a8fd57c51f7..84c822d989da 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1391,20 +1391,21 @@ out_free_disk:
 	return NULL;
 }
 
-struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass)
+struct gendisk *__blk_alloc_disk(struct queue_limits *lim, int node,
+		struct lock_class_key *lkclass)
 {
-	struct queue_limits lim = { };
+	struct queue_limits default_lim = { };
 	struct request_queue *q;
 	struct gendisk *disk;
 
-	q = blk_alloc_queue(&lim, node);
+	q = blk_alloc_queue(lim ? lim : &default_lim, node);
 	if (IS_ERR(q))
-		return NULL;
+		return ERR_CAST(q);
 
 	disk = __alloc_disk_node(q, node, lkclass);
 	if (!disk) {
 		blk_put_queue(q);
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 	}
 	set_bit(GD_OWNS_QUEUE, &disk->state);
 	return disk;
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 970bd6ff38c4..689a3c0c31f8 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -335,10 +335,11 @@ static int brd_alloc(int i)
 		debugfs_create_u64(buf, 0444, brd_debugfs_dir,
 				&brd->brd_nr_pages);
 
-	disk = brd->brd_disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!disk)
+	disk = brd->brd_disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(disk)) {
+		err = PTR_ERR(disk);
 		goto out_free_dev;
-
+	}
 	disk->major		= RAMDISK_MAJOR;
 	disk->first_minor	= i * max_part;
 	disk->minors		= max_part;
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 6bc86106c7b2..cea1e537fd56 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2708,9 +2708,11 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
 
 	drbd_init_set_defaults(device);
 
-	disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!disk)
+	disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(disk)) {
+		err = PTR_ERR(disk);
 		goto out_no_disk;
+	}
 
 	device->vdisk = disk;
 	device->rq_queue = disk->queue;
diff --git a/drivers/block/n64cart.c b/drivers/block/n64cart.c
index d914156db2d8..c64d7ee7a44d 100644
--- a/drivers/block/n64cart.c
+++ b/drivers/block/n64cart.c
@@ -131,9 +131,11 @@ static int __init n64cart_probe(struct platform_device *pdev)
 	if (IS_ERR(reg_base))
 		return PTR_ERR(reg_base);
 
-	disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!disk)
+	disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(disk)) {
+		err = PTR_ERR(disk);
 		goto out;
+	}
 
 	disk->first_minor = 0;
 	disk->flags = GENHD_FL_NO_PART;
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index eeb895ec6f34..baf2b228d008 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -2154,10 +2154,11 @@ static int null_add_dev(struct nullb_device *dev)
 		}
 		nullb->q = nullb->disk->queue;
 	} else if (dev->queue_mode == NULL_Q_BIO) {
-		rv = -ENOMEM;
-		nullb->disk = blk_alloc_disk(nullb->dev->home_node);
-		if (!nullb->disk)
+		nullb->disk = blk_alloc_disk(NULL, nullb->dev->home_node);
+		if (IS_ERR(nullb->disk)) {
+			rv = PTR_ERR(nullb->disk);
 			goto out_cleanup_queues;
+		}
 
 		nullb->q = nullb->disk->queue;
 		rv = init_driver_queues(nullb);
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index d56d972aadb3..abb82926b1c9 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2673,10 +2673,11 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	pd->write_congestion_on  = write_congestion_on;
 	pd->write_congestion_off = write_congestion_off;
 
-	ret = -ENOMEM;
-	disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!disk)
+	disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(disk)) {
+		ret = PTR_ERR(disk);
 		goto out_mem;
+	}
 	pd->disk = disk;
 	disk->major = pktdev_major;
 	disk->first_minor = idx;
diff --git a/drivers/block/ps3vram.c b/drivers/block/ps3vram.c
index 38d42af01b25..bdcf083b45e2 100644
--- a/drivers/block/ps3vram.c
+++ b/drivers/block/ps3vram.c
@@ -730,10 +730,10 @@ static int ps3vram_probe(struct ps3_system_bus_device *dev)
 
 	ps3vram_proc_init(dev);
 
-	gendisk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!gendisk) {
+	gendisk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(gendisk)) {
 		dev_err(&dev->core, "blk_alloc_disk failed\n");
-		error = -ENOMEM;
+		error = PTR_ERR(gendisk);
 		goto out_cache_cleanup;
 	}
 
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 6772e0c654fa..84982221fc66 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -2195,11 +2195,11 @@ static int zram_add(void)
 #endif
 
 	/* gendisk structure */
-	zram->disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!zram->disk) {
+	zram->disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(zram->disk)) {
 		pr_err("Error allocating disk structure for device %d\n",
 			device_id);
-		ret = -ENOMEM;
+		ret = PTR_ERR(zram->disk);
 		goto out_free_idr;
 	}
 
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index dc3f50f69714..9955ecff3839 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -935,8 +935,8 @@ static int bcache_device_init(struct bcache_device *d, unsigned int block_size,
 			BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER))
 		goto out_ida_remove;
 
-	d->disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!d->disk)
+	d->disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(d->disk))
 		goto out_bioset_exit;
 
 	set_capacity(d->disk, sectors);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8dcabf84d866..b5e6a10b9cfd 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2098,8 +2098,8 @@ static struct mapped_device *alloc_dev(int minor)
 	 * established. If request-based table is loaded: blk-mq will
 	 * override accordingly.
 	 */
-	md->disk = blk_alloc_disk(md->numa_node_id);
-	if (!md->disk)
+	md->disk = blk_alloc_disk(NULL, md->numa_node_id);
+	if (IS_ERR(md->disk))
 		goto bad;
 	md->queue = md->disk->queue;
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index e2a5f513dbb7..75266c34b1f9 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5763,10 +5763,11 @@ struct mddev *md_alloc(dev_t dev, char *name)
 		 */
 		mddev->hold_active = UNTIL_STOP;
 
-	error = -ENOMEM;
-	disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!disk)
+	disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(disk)) {
+		error = PTR_ERR(disk);
 		goto out_free_mddev;
+	}
 
 	disk->major = MAJOR(mddev->unit);
 	disk->first_minor = unit << shift;
diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index bb3726b622ad..9a0eae01d598 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -1496,11 +1496,11 @@ static int btt_blk_init(struct btt *btt)
 {
 	struct nd_btt *nd_btt = btt->nd_btt;
 	struct nd_namespace_common *ndns = nd_btt->ndns;
-	int rc = -ENOMEM;
+	int rc;
 
-	btt->btt_disk = blk_alloc_disk(NUMA_NO_NODE);
-	if (!btt->btt_disk)
-		return -ENOMEM;
+	btt->btt_disk = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(btt->btt_disk))
+		return PTR_ERR(btt->btt_disk);
 
 	nvdimm_namespace_disk_name(ndns, btt->btt_disk->disk_name);
 	btt->btt_disk->first_minor = 0;
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 4e8fdcb3f1c8..3a5df8d467c5 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -497,9 +497,9 @@ static int pmem_attach_disk(struct device *dev,
 		return -EBUSY;
 	}
 
-	disk = blk_alloc_disk(nid);
-	if (!disk)
-		return -ENOMEM;
+	disk = blk_alloc_disk(NULL, nid);
+	if (IS_ERR(disk))
+		return PTR_ERR(disk);
 	q = disk->queue;
 
 	pmem->disk = disk;
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 74de1e64aeea..dc5d0d0a82d0 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -532,9 +532,9 @@ int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head)
 	    !nvme_is_unique_nsid(ctrl, head) || !multipath)
 		return 0;
 
-	head->disk = blk_alloc_disk(ctrl->numa_node);
-	if (!head->disk)
-		return -ENOMEM;
+	head->disk = blk_alloc_disk(NULL, ctrl->numa_node);
+	if (IS_ERR(head->disk))
+		return PTR_ERR(head->disk);
 	head->disk->fops = &nvme_ns_head_ops;
 	head->disk->private_data = head;
 	sprintf(head->disk->disk_name, "nvme%dn%d",
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 4b7ecd4fd431..0903b432ea97 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -629,9 +629,9 @@ dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char
 	dev_info->dev.release = dcssblk_release_segment;
 	dev_info->dev.groups = dcssblk_dev_attr_groups;
 	INIT_LIST_HEAD(&dev_info->lh);
-	dev_info->gd = blk_alloc_disk(NUMA_NO_NODE);
-	if (dev_info->gd == NULL) {
-		rc = -ENOMEM;
+	dev_info->gd = blk_alloc_disk(NULL, NUMA_NO_NODE);
+	if (IS_ERR(dev_info->gd)) {
+		rc = PTR_ERR(dev_info->gd);
 		goto seg_list_del;
 	}
 	dev_info->gd->major = dcssblk_major;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 45746ba73670..a14ea9344138 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -766,22 +766,26 @@ static inline u64 sb_bdev_nr_blocks(struct super_block *sb)
 int bdev_disk_changed(struct gendisk *disk, bool invalidate);
 
 void put_disk(struct gendisk *disk);
-struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass);
+struct gendisk *__blk_alloc_disk(struct queue_limits *lim, int node,
+		struct lock_class_key *lkclass);
 
 /**
  * blk_alloc_disk - allocate a gendisk structure
+ * @lim: queue limits to be used for this disk.
  * @node_id: numa node to allocate on
  *
  * Allocate and pre-initialize a gendisk structure for use with BIO based
  * drivers.
  *
+ * Returns an ERR_PTR on error, else the allocated disk.
+ *
  * Context: can sleep
  */
-#define blk_alloc_disk(node_id)						\
+#define blk_alloc_disk(lim, node_id)					\
 ({									\
 	static struct lock_class_key __key;				\
 									\
-	__blk_alloc_disk(node_id, &__key);				\
+	__blk_alloc_disk(lim, node_id, &__key);				\
 })
 
 int __register_blkdev(unsigned int major, const char *name,
-- 
cgit v1.2.3


From 8b631f9cf0b84ac59cd4f0c6dcd2d0cb80dd8a49 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Feb 2024 10:32:44 +0100
Subject: null_blk: remove the bio based I/O path

The bio based I/O path complicates null_blk and also make various
data structures, including the per-command one way bigger than
required for the main request based interface.   As the bio-based
path is mostly used by stacking drivers and simple memory based
drivers, and brd is a good example driver for the latter there is
no need to have a bio based path in null_blk.  Remove the path
to simplify the driver and make future block layer API changes
simpler by not having to deal with the complex two API setup in
null_blk.

Note that the queue_mode field in struct nullb_device is kept as
that is simpler than having two different places to check the
value and fully open coding the debugfs helpers as the existing
ones won't work without a named struct member.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c     | 365 +++++++-------------------------------
 drivers/block/null_blk/null_blk.h |  17 --
 drivers/block/null_blk/trace.h    |   5 +-
 drivers/block/null_blk/zoned.c    |  10 +-
 4 files changed, 69 insertions(+), 328 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index baf2b228d008..d6836327eefb 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -115,6 +115,18 @@ module_param_string(init_hctx, g_init_hctx_str, sizeof(g_init_hctx_str), 0444);
 MODULE_PARM_DESC(init_hctx, "Fault injection to fail hctx init. init_hctx=<interval>,<probability>,<space>,<times>");
 #endif
 
+/*
+ * Historic queue modes.
+ *
+ * These days nothing but NULL_Q_MQ is actually supported, but we keep it the
+ * enum for error reporting.
+ */
+enum {
+	NULL_Q_BIO	= 0,
+	NULL_Q_RQ	= 1,
+	NULL_Q_MQ	= 2,
+};
+
 static int g_queue_mode = NULL_Q_MQ;
 
 static int null_param_store_val(const char *str, int *val, int min, int max)
@@ -756,98 +768,11 @@ static void null_free_dev(struct nullb_device *dev)
 	kfree(dev);
 }
 
-static void put_tag(struct nullb_queue *nq, unsigned int tag)
-{
-	clear_bit_unlock(tag, nq->tag_map);
-
-	if (waitqueue_active(&nq->wait))
-		wake_up(&nq->wait);
-}
-
-static unsigned int get_tag(struct nullb_queue *nq)
-{
-	unsigned int tag;
-
-	do {
-		tag = find_first_zero_bit(nq->tag_map, nq->queue_depth);
-		if (tag >= nq->queue_depth)
-			return -1U;
-	} while (test_and_set_bit_lock(tag, nq->tag_map));
-
-	return tag;
-}
-
-static void free_cmd(struct nullb_cmd *cmd)
-{
-	put_tag(cmd->nq, cmd->tag);
-}
-
-static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer);
-
-static struct nullb_cmd *__alloc_cmd(struct nullb_queue *nq)
-{
-	struct nullb_cmd *cmd;
-	unsigned int tag;
-
-	tag = get_tag(nq);
-	if (tag != -1U) {
-		cmd = &nq->cmds[tag];
-		cmd->tag = tag;
-		cmd->error = BLK_STS_OK;
-		cmd->nq = nq;
-		if (nq->dev->irqmode == NULL_IRQ_TIMER) {
-			hrtimer_init(&cmd->timer, CLOCK_MONOTONIC,
-				     HRTIMER_MODE_REL);
-			cmd->timer.function = null_cmd_timer_expired;
-		}
-		return cmd;
-	}
-
-	return NULL;
-}
-
-static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq, struct bio *bio)
-{
-	struct nullb_cmd *cmd;
-	DEFINE_WAIT(wait);
-
-	do {
-		/*
-		 * This avoids multiple return statements, multiple calls to
-		 * __alloc_cmd() and a fast path call to prepare_to_wait().
-		 */
-		cmd = __alloc_cmd(nq);
-		if (cmd) {
-			cmd->bio = bio;
-			return cmd;
-		}
-		prepare_to_wait(&nq->wait, &wait, TASK_UNINTERRUPTIBLE);
-		io_schedule();
-		finish_wait(&nq->wait, &wait);
-	} while (1);
-}
-
-static void end_cmd(struct nullb_cmd *cmd)
-{
-	int queue_mode = cmd->nq->dev->queue_mode;
-
-	switch (queue_mode)  {
-	case NULL_Q_MQ:
-		blk_mq_end_request(cmd->rq, cmd->error);
-		return;
-	case NULL_Q_BIO:
-		cmd->bio->bi_status = cmd->error;
-		bio_endio(cmd->bio);
-		break;
-	}
-
-	free_cmd(cmd);
-}
-
 static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer)
 {
-	end_cmd(container_of(timer, struct nullb_cmd, timer));
+	struct nullb_cmd *cmd = container_of(timer, struct nullb_cmd, timer);
 
+	blk_mq_end_request(blk_mq_rq_from_pdu(cmd), cmd->error);
 	return HRTIMER_NORESTART;
 }
 
@@ -860,7 +785,9 @@ static void null_cmd_end_timer(struct nullb_cmd *cmd)
 
 static void null_complete_rq(struct request *rq)
 {
-	end_cmd(blk_mq_rq_to_pdu(rq));
+	struct nullb_cmd *cmd = blk_mq_rq_to_pdu(rq);
+
+	blk_mq_end_request(rq, cmd->error);
 }
 
 static struct nullb_page *null_alloc_page(void)
@@ -1277,7 +1204,7 @@ static int null_transfer(struct nullb *nullb, struct page *page,
 
 static int null_handle_rq(struct nullb_cmd *cmd)
 {
-	struct request *rq = cmd->rq;
+	struct request *rq = blk_mq_rq_from_pdu(cmd);
 	struct nullb *nullb = cmd->nq->dev->nullb;
 	int err;
 	unsigned int len;
@@ -1302,63 +1229,21 @@ static int null_handle_rq(struct nullb_cmd *cmd)
 	return 0;
 }
 
-static int null_handle_bio(struct nullb_cmd *cmd)
-{
-	struct bio *bio = cmd->bio;
-	struct nullb *nullb = cmd->nq->dev->nullb;
-	int err;
-	unsigned int len;
-	sector_t sector = bio->bi_iter.bi_sector;
-	struct bio_vec bvec;
-	struct bvec_iter iter;
-
-	spin_lock_irq(&nullb->lock);
-	bio_for_each_segment(bvec, bio, iter) {
-		len = bvec.bv_len;
-		err = null_transfer(nullb, bvec.bv_page, len, bvec.bv_offset,
-				     op_is_write(bio_op(bio)), sector,
-				     bio->bi_opf & REQ_FUA);
-		if (err) {
-			spin_unlock_irq(&nullb->lock);
-			return err;
-		}
-		sector += len >> SECTOR_SHIFT;
-	}
-	spin_unlock_irq(&nullb->lock);
-	return 0;
-}
-
-static void null_stop_queue(struct nullb *nullb)
-{
-	struct request_queue *q = nullb->q;
-
-	if (nullb->dev->queue_mode == NULL_Q_MQ)
-		blk_mq_stop_hw_queues(q);
-}
-
-static void null_restart_queue_async(struct nullb *nullb)
-{
-	struct request_queue *q = nullb->q;
-
-	if (nullb->dev->queue_mode == NULL_Q_MQ)
-		blk_mq_start_stopped_hw_queues(q, true);
-}
-
 static inline blk_status_t null_handle_throttled(struct nullb_cmd *cmd)
 {
 	struct nullb_device *dev = cmd->nq->dev;
 	struct nullb *nullb = dev->nullb;
 	blk_status_t sts = BLK_STS_OK;
-	struct request *rq = cmd->rq;
+	struct request *rq = blk_mq_rq_from_pdu(cmd);
 
 	if (!hrtimer_active(&nullb->bw_timer))
 		hrtimer_restart(&nullb->bw_timer);
 
 	if (atomic_long_sub_return(blk_rq_bytes(rq), &nullb->cur_bytes) < 0) {
-		null_stop_queue(nullb);
+		blk_mq_stop_hw_queues(nullb->q);
 		/* race with timer */
 		if (atomic_long_read(&nullb->cur_bytes) > 0)
-			null_restart_queue_async(nullb);
+			blk_mq_start_stopped_hw_queues(nullb->q, true);
 		/* requeue request */
 		sts = BLK_STS_DEV_RESOURCE;
 	}
@@ -1385,37 +1270,29 @@ static inline blk_status_t null_handle_memory_backed(struct nullb_cmd *cmd,
 						     sector_t nr_sectors)
 {
 	struct nullb_device *dev = cmd->nq->dev;
-	int err;
 
 	if (op == REQ_OP_DISCARD)
 		return null_handle_discard(dev, sector, nr_sectors);
+	return errno_to_blk_status(null_handle_rq(cmd));
 
-	if (dev->queue_mode == NULL_Q_BIO)
-		err = null_handle_bio(cmd);
-	else
-		err = null_handle_rq(cmd);
-
-	return errno_to_blk_status(err);
 }
 
 static void nullb_zero_read_cmd_buffer(struct nullb_cmd *cmd)
 {
+	struct request *rq = blk_mq_rq_from_pdu(cmd);
 	struct nullb_device *dev = cmd->nq->dev;
 	struct bio *bio;
 
-	if (dev->memory_backed)
-		return;
-
-	if (dev->queue_mode == NULL_Q_BIO && bio_op(cmd->bio) == REQ_OP_READ) {
-		zero_fill_bio(cmd->bio);
-	} else if (req_op(cmd->rq) == REQ_OP_READ) {
-		__rq_for_each_bio(bio, cmd->rq)
+	if (!dev->memory_backed && req_op(rq) == REQ_OP_READ) {
+		__rq_for_each_bio(bio, rq)
 			zero_fill_bio(bio);
 	}
 }
 
 static inline void nullb_complete_cmd(struct nullb_cmd *cmd)
 {
+	struct request *rq = blk_mq_rq_from_pdu(cmd);
+
 	/*
 	 * Since root privileges are required to configure the null_blk
 	 * driver, it is fine that this driver does not initialize the
@@ -1429,20 +1306,10 @@ static inline void nullb_complete_cmd(struct nullb_cmd *cmd)
 	/* Complete IO by inline, softirq or timer */
 	switch (cmd->nq->dev->irqmode) {
 	case NULL_IRQ_SOFTIRQ:
-		switch (cmd->nq->dev->queue_mode) {
-		case NULL_Q_MQ:
-			blk_mq_complete_request(cmd->rq);
-			break;
-		case NULL_Q_BIO:
-			/*
-			 * XXX: no proper submitting cpu information available.
-			 */
-			end_cmd(cmd);
-			break;
-		}
+		blk_mq_complete_request(rq);
 		break;
 	case NULL_IRQ_NONE:
-		end_cmd(cmd);
+		blk_mq_end_request(rq, cmd->error);
 		break;
 	case NULL_IRQ_TIMER:
 		null_cmd_end_timer(cmd);
@@ -1503,7 +1370,7 @@ static enum hrtimer_restart nullb_bwtimer_fn(struct hrtimer *timer)
 		return HRTIMER_NORESTART;
 
 	atomic_long_set(&nullb->cur_bytes, mb_per_tick(mbps));
-	null_restart_queue_async(nullb);
+	blk_mq_start_stopped_hw_queues(nullb->q, true);
 
 	hrtimer_forward_now(&nullb->bw_timer, timer_interval);
 
@@ -1520,26 +1387,6 @@ static void nullb_setup_bwtimer(struct nullb *nullb)
 	hrtimer_start(&nullb->bw_timer, timer_interval, HRTIMER_MODE_REL);
 }
 
-static struct nullb_queue *nullb_to_queue(struct nullb *nullb)
-{
-	int index = 0;
-
-	if (nullb->nr_queues != 1)
-		index = raw_smp_processor_id() / ((nr_cpu_ids + nullb->nr_queues - 1) / nullb->nr_queues);
-
-	return &nullb->queues[index];
-}
-
-static void null_submit_bio(struct bio *bio)
-{
-	sector_t sector = bio->bi_iter.bi_sector;
-	sector_t nr_sectors = bio_sectors(bio);
-	struct nullb *nullb = bio->bi_bdev->bd_disk->private_data;
-	struct nullb_queue *nq = nullb_to_queue(nullb);
-
-	null_handle_cmd(alloc_cmd(nq, bio), sector, nr_sectors, bio_op(bio));
-}
-
 #ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION
 
 static bool should_timeout_request(struct request *rq)
@@ -1659,7 +1506,7 @@ static int null_poll(struct blk_mq_hw_ctx *hctx, struct io_comp_batch *iob)
 						blk_rq_sectors(req));
 		if (!blk_mq_add_to_batch(req, iob, (__force int) cmd->error,
 					blk_mq_end_request_batch))
-			end_cmd(cmd);
+			blk_mq_end_request(req, cmd->error);
 		nr++;
 	}
 
@@ -1715,7 +1562,6 @@ static blk_status_t null_queue_rq(struct blk_mq_hw_ctx *hctx,
 		hrtimer_init(&cmd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 		cmd->timer.function = null_cmd_timer_expired;
 	}
-	cmd->rq = rq;
 	cmd->error = BLK_STS_OK;
 	cmd->nq = nq;
 	cmd->fake_timeout = should_timeout_request(rq) ||
@@ -1774,22 +1620,6 @@ static void null_queue_rqs(struct request **rqlist)
 	*rqlist = requeue_list;
 }
 
-static void cleanup_queue(struct nullb_queue *nq)
-{
-	bitmap_free(nq->tag_map);
-	kfree(nq->cmds);
-}
-
-static void cleanup_queues(struct nullb *nullb)
-{
-	int i;
-
-	for (i = 0; i < nullb->nr_queues; i++)
-		cleanup_queue(&nullb->queues[i]);
-
-	kfree(nullb->queues);
-}
-
 static void null_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
 {
 	struct nullb_queue *nq = hctx->driver_data;
@@ -1800,8 +1630,6 @@ static void null_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
 
 static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq)
 {
-	init_waitqueue_head(&nq->wait);
-	nq->queue_depth = nullb->queue_depth;
 	nq->dev = nullb->dev;
 	INIT_LIST_HEAD(&nq->poll_list);
 	spin_lock_init(&nq->poll_lock);
@@ -1853,14 +1681,13 @@ static void null_del_dev(struct nullb *nullb)
 	if (test_bit(NULLB_DEV_FL_THROTTLED, &nullb->dev->flags)) {
 		hrtimer_cancel(&nullb->bw_timer);
 		atomic_long_set(&nullb->cur_bytes, LONG_MAX);
-		null_restart_queue_async(nullb);
+		blk_mq_start_stopped_hw_queues(nullb->q, true);
 	}
 
 	put_disk(nullb->disk);
-	if (dev->queue_mode == NULL_Q_MQ &&
-	    nullb->tag_set == &nullb->__tag_set)
+	if (nullb->tag_set == &nullb->__tag_set)
 		blk_mq_free_tag_set(nullb->tag_set);
-	cleanup_queues(nullb);
+	kfree(nullb->queues);
 	if (null_cache_active(nullb))
 		null_free_device_storage(nullb->dev, true);
 	kfree(nullb);
@@ -1887,40 +1714,11 @@ static void null_config_discard(struct nullb *nullb)
 	blk_queue_max_discard_sectors(nullb->q, UINT_MAX >> 9);
 }
 
-static const struct block_device_operations null_bio_ops = {
+static const struct block_device_operations null_ops = {
 	.owner		= THIS_MODULE,
-	.submit_bio	= null_submit_bio,
 	.report_zones	= null_report_zones,
 };
 
-static const struct block_device_operations null_rq_ops = {
-	.owner		= THIS_MODULE,
-	.report_zones	= null_report_zones,
-};
-
-static int setup_commands(struct nullb_queue *nq)
-{
-	struct nullb_cmd *cmd;
-	int i;
-
-	nq->cmds = kcalloc(nq->queue_depth, sizeof(*cmd), GFP_KERNEL);
-	if (!nq->cmds)
-		return -ENOMEM;
-
-	nq->tag_map = bitmap_zalloc(nq->queue_depth, GFP_KERNEL);
-	if (!nq->tag_map) {
-		kfree(nq->cmds);
-		return -ENOMEM;
-	}
-
-	for (i = 0; i < nq->queue_depth; i++) {
-		cmd = &nq->cmds[i];
-		cmd->tag = -1U;
-	}
-
-	return 0;
-}
-
 static int setup_queues(struct nullb *nullb)
 {
 	int nqueues = nr_cpu_ids;
@@ -1937,24 +1735,6 @@ static int setup_queues(struct nullb *nullb)
 	return 0;
 }
 
-static int init_driver_queues(struct nullb *nullb)
-{
-	struct nullb_queue *nq;
-	int i, ret = 0;
-
-	for (i = 0; i < nullb->dev->submit_queues; i++) {
-		nq = &nullb->queues[i];
-
-		null_init_queue(nullb, nq);
-
-		ret = setup_commands(nq);
-		if (ret)
-			return ret;
-		nullb->nr_queues++;
-	}
-	return 0;
-}
-
 static int null_gendisk_register(struct nullb *nullb)
 {
 	sector_t size = ((sector_t)nullb->dev->size * SZ_1M) >> SECTOR_SHIFT;
@@ -1965,10 +1745,7 @@ static int null_gendisk_register(struct nullb *nullb)
 	disk->major		= null_major;
 	disk->first_minor	= nullb->index;
 	disk->minors		= 1;
-	if (queue_is_mq(nullb->q))
-		disk->fops		= &null_rq_ops;
-	else
-		disk->fops		= &null_bio_ops;
+	disk->fops		= &null_ops;
 	disk->private_data	= nullb;
 	strscpy_pad(disk->disk_name, nullb->disk_name, DISK_NAME_LEN);
 
@@ -2036,11 +1813,15 @@ static int null_validate_conf(struct nullb_device *dev)
 		pr_err("legacy IO path is no longer available\n");
 		return -EINVAL;
 	}
+	if (dev->queue_mode == NULL_Q_BIO) {
+		pr_err("BIO-based IO path is no longer available, using blk-mq instead.\n");
+		dev->queue_mode = NULL_Q_MQ;
+	}
 
 	dev->blocksize = round_down(dev->blocksize, 512);
 	dev->blocksize = clamp_t(unsigned int, dev->blocksize, 512, 4096);
 
-	if (dev->queue_mode == NULL_Q_MQ && dev->use_per_node_hctx) {
+	if (dev->use_per_node_hctx) {
 		if (dev->submit_queues != nr_online_nodes)
 			dev->submit_queues = nr_online_nodes;
 	} else if (dev->submit_queues > nr_cpu_ids)
@@ -2052,8 +1833,6 @@ static int null_validate_conf(struct nullb_device *dev)
 	if (dev->poll_queues > g_poll_queues)
 		dev->poll_queues = g_poll_queues;
 	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);
 
 	/* Do memory allocation, so set blocking */
@@ -2064,9 +1843,6 @@ static int null_validate_conf(struct nullb_device *dev)
 	dev->cache_size = min_t(unsigned long, ULONG_MAX / 1024 / 1024,
 						dev->cache_size);
 	dev->mbps = min_t(unsigned int, 1024 * 40, dev->mbps);
-	/* can not stop a queue */
-	if (dev->queue_mode == NULL_Q_BIO)
-		dev->mbps = 0;
 
 	if (dev->zoned &&
 	    (!dev->zone_size || !is_power_of_2(dev->zone_size))) {
@@ -2127,44 +1903,31 @@ static int null_add_dev(struct nullb_device *dev)
 	if (rv)
 		goto out_free_nullb;
 
-	if (dev->queue_mode == NULL_Q_MQ) {
-		if (dev->shared_tags) {
-			if (!tag_set.ops) {
-				rv = null_init_tag_set(NULL, &tag_set);
-				if (rv) {
-					tag_set.ops = NULL;
-					goto out_cleanup_queues;
-				}
+	if (dev->shared_tags) {
+		if (!tag_set.ops) {
+			rv = null_init_tag_set(NULL, &tag_set);
+			if (rv) {
+				tag_set.ops = NULL;
+				goto out_cleanup_queues;
 			}
-			nullb->tag_set = &tag_set;
-			rv = 0;
-		} else {
-			nullb->tag_set = &nullb->__tag_set;
-			rv = null_init_tag_set(nullb, nullb->tag_set);
 		}
+		nullb->tag_set = &tag_set;
+		rv = 0;
+	} else {
+		nullb->tag_set = &nullb->__tag_set;
+		rv = null_init_tag_set(nullb, nullb->tag_set);
+	}
 
-		if (rv)
-			goto out_cleanup_queues;
-
-		nullb->tag_set->timeout = 5 * HZ;
-		nullb->disk = blk_mq_alloc_disk(nullb->tag_set, NULL, nullb);
-		if (IS_ERR(nullb->disk)) {
-			rv = PTR_ERR(nullb->disk);
-			goto out_cleanup_tags;
-		}
-		nullb->q = nullb->disk->queue;
-	} else if (dev->queue_mode == NULL_Q_BIO) {
-		nullb->disk = blk_alloc_disk(NULL, nullb->dev->home_node);
-		if (IS_ERR(nullb->disk)) {
-			rv = PTR_ERR(nullb->disk);
-			goto out_cleanup_queues;
-		}
+	if (rv)
+		goto out_cleanup_queues;
 
-		nullb->q = nullb->disk->queue;
-		rv = init_driver_queues(nullb);
-		if (rv)
-			goto out_cleanup_disk;
+	nullb->tag_set->timeout = 5 * HZ;
+	nullb->disk = blk_mq_alloc_disk(nullb->tag_set, NULL, nullb);
+	if (IS_ERR(nullb->disk)) {
+		rv = PTR_ERR(nullb->disk);
+		goto out_cleanup_tags;
 	}
+	nullb->q = nullb->disk->queue;
 
 	if (dev->mbps) {
 		set_bit(NULLB_DEV_FL_THROTTLED, &dev->flags);
@@ -2232,10 +1995,10 @@ out_cleanup_zone:
 out_cleanup_disk:
 	put_disk(nullb->disk);
 out_cleanup_tags:
-	if (dev->queue_mode == NULL_Q_MQ && nullb->tag_set == &nullb->__tag_set)
+	if (nullb->tag_set == &nullb->__tag_set)
 		blk_mq_free_tag_set(nullb->tag_set);
 out_cleanup_queues:
-	cleanup_queues(nullb);
+	kfree(nullb->queues);
 out_free_nullb:
 	kfree(nullb);
 	dev->nullb = NULL;
@@ -2311,7 +2074,7 @@ static int __init null_init(void)
 		return -EINVAL;
 	}
 
-	if (g_queue_mode == NULL_Q_MQ && g_use_per_node_hctx) {
+	if (g_use_per_node_hctx) {
 		if (g_submit_queues != nr_online_nodes) {
 			pr_warn("submit_queues param is set to %u.\n",
 				nr_online_nodes);
diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h
index 7bcfc0922ae8..7c618d53d8fd 100644
--- a/drivers/block/null_blk/null_blk.h
+++ b/drivers/block/null_blk/null_blk.h
@@ -16,11 +16,6 @@
 #include <linux/mutex.h>
 
 struct nullb_cmd {
-	union {
-		struct request *rq;
-		struct bio *bio;
-	};
-	unsigned int tag;
 	blk_status_t error;
 	bool fake_timeout;
 	struct nullb_queue *nq;
@@ -28,16 +23,11 @@ struct nullb_cmd {
 };
 
 struct nullb_queue {
-	unsigned long *tag_map;
-	wait_queue_head_t wait;
-	unsigned int queue_depth;
 	struct nullb_device *dev;
 	unsigned int requeue_selection;
 
 	struct list_head poll_list;
 	spinlock_t poll_lock;
-
-	struct nullb_cmd *cmds;
 };
 
 struct nullb_zone {
@@ -60,13 +50,6 @@ struct nullb_zone {
 	unsigned int capacity;
 };
 
-/* Queue modes */
-enum {
-	NULL_Q_BIO	= 0,
-	NULL_Q_RQ	= 1,
-	NULL_Q_MQ	= 2,
-};
-
 struct nullb_device {
 	struct nullb *nullb;
 	struct config_group group;
diff --git a/drivers/block/null_blk/trace.h b/drivers/block/null_blk/trace.h
index 6b2b370e786f..ef2d05d5f0df 100644
--- a/drivers/block/null_blk/trace.h
+++ b/drivers/block/null_blk/trace.h
@@ -41,10 +41,11 @@ TRACE_EVENT(nullb_zone_op,
 		__field(unsigned int, zone_cond)
 	    ),
 	    TP_fast_assign(
-		__entry->op = req_op(cmd->rq);
+		__entry->op = req_op(blk_mq_rq_from_pdu(cmd));
 		__entry->zone_no = zone_no;
 		__entry->zone_cond = zone_cond;
-		__assign_disk_name(__entry->disk, cmd->rq->q->disk);
+		__assign_disk_name(__entry->disk,
+			blk_mq_rq_from_pdu(cmd)->q->disk);
 	    ),
 	    TP_printk("%s req=%-15s zone_no=%u zone_cond=%-10s",
 		      __print_disk_name(__entry->disk),
diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c
index 6f5e0994862e..3605afe105da 100644
--- a/drivers/block/null_blk/zoned.c
+++ b/drivers/block/null_blk/zoned.c
@@ -168,10 +168,7 @@ int null_register_zoned_dev(struct nullb *nullb)
 	disk_set_max_open_zones(nullb->disk, dev->zone_max_open);
 	disk_set_max_active_zones(nullb->disk, dev->zone_max_active);
 
-	if (queue_is_mq(q))
-		return blk_revalidate_disk_zones(nullb->disk, NULL);
-
-	return 0;
+	return blk_revalidate_disk_zones(nullb->disk, NULL);
 }
 
 void null_free_zoned_dev(struct nullb_device *dev)
@@ -394,10 +391,7 @@ static blk_status_t null_zone_write(struct nullb_cmd *cmd, sector_t sector,
 	 */
 	if (append) {
 		sector = zone->wp;
-		if (dev->queue_mode == NULL_Q_MQ)
-			cmd->rq->__sector = sector;
-		else
-			cmd->bio->bi_iter.bi_sector = sector;
+		blk_mq_rq_from_pdu(cmd)->__sector = sector;
 	} else if (sector != zone->wp) {
 		ret = BLK_STS_IOERR;
 		goto unlock;
-- 
cgit v1.2.3


From e32b0855367b65095823b4427aad3da7c6a771a6 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Feb 2024 10:32:45 +0100
Subject: null_blk: initialize the tag_set timeout in null_init_tag_set

Otherwise it will be reset to the always same value when initializing a
device using the shared tag_set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index d6836327eefb..89e63d1c6103 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1797,6 +1797,7 @@ static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set)
 	set->nr_hw_queues = hw_queues;
 	set->queue_depth = queue_depth;
 	set->numa_node = numa_node;
+	set->timeout = 5 * HZ;
 	if (poll_queues) {
 		set->nr_hw_queues += poll_queues;
 		set->nr_maps = 3;
@@ -1921,7 +1922,6 @@ static int null_add_dev(struct nullb_device *dev)
 	if (rv)
 		goto out_cleanup_queues;
 
-	nullb->tag_set->timeout = 5 * HZ;
 	nullb->disk = blk_mq_alloc_disk(nullb->tag_set, NULL, nullb);
 	if (IS_ERR(nullb->disk)) {
 		rv = PTR_ERR(nullb->disk);
-- 
cgit v1.2.3


From 72ca28765fc461c1aeb87372359ec0cfd609448b Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Feb 2024 10:32:46 +0100
Subject: null_blk: refactor tag_set setup

Move the tagset initialization out of null_add_dev into a new
null_setup_tagset helper, and move the shared vs local differences
out of null_init_tag_set into the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c | 106 ++++++++++++++++++++----------------------
 1 file changed, 51 insertions(+), 55 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 89e63d1c6103..03c3917a56fa 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1759,55 +1759,65 @@ static int null_gendisk_register(struct nullb *nullb)
 	return add_disk(disk);
 }
 
-static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set)
+static int null_init_tag_set(struct blk_mq_tag_set *set, int poll_queues)
 {
-	unsigned int flags = BLK_MQ_F_SHOULD_MERGE;
-	int hw_queues, numa_node;
-	unsigned int queue_depth;
-	int poll_queues;
-
-	if (nullb) {
-		hw_queues = nullb->dev->submit_queues;
-		poll_queues = nullb->dev->poll_queues;
-		queue_depth = nullb->dev->hw_queue_depth;
-		numa_node = nullb->dev->home_node;
-		if (nullb->dev->no_sched)
-			flags |= BLK_MQ_F_NO_SCHED;
-		if (nullb->dev->shared_tag_bitmap)
-			flags |= BLK_MQ_F_TAG_HCTX_SHARED;
-		if (nullb->dev->blocking)
-			flags |= BLK_MQ_F_BLOCKING;
-	} else {
-		hw_queues = g_submit_queues;
-		poll_queues = g_poll_queues;
-		queue_depth = g_hw_queue_depth;
-		numa_node = g_home_node;
-		if (g_no_sched)
-			flags |= BLK_MQ_F_NO_SCHED;
-		if (g_shared_tag_bitmap)
-			flags |= BLK_MQ_F_TAG_HCTX_SHARED;
-		if (g_blocking)
-			flags |= BLK_MQ_F_BLOCKING;
-	}
-
 	set->ops = &null_mq_ops;
-	set->cmd_size	= sizeof(struct nullb_cmd);
-	set->flags = flags;
-	set->driver_data = nullb;
-	set->nr_hw_queues = hw_queues;
-	set->queue_depth = queue_depth;
-	set->numa_node = numa_node;
+	set->cmd_size = sizeof(struct nullb_cmd);
 	set->timeout = 5 * HZ;
+	set->nr_maps = 1;
 	if (poll_queues) {
 		set->nr_hw_queues += poll_queues;
-		set->nr_maps = 3;
-	} else {
-		set->nr_maps = 1;
+		set->nr_maps += 2;
 	}
-
 	return blk_mq_alloc_tag_set(set);
 }
 
+static int null_init_global_tag_set(void)
+{
+	int error;
+
+	if (tag_set.ops)
+		return 0;
+
+	tag_set.nr_hw_queues = g_submit_queues;
+	tag_set.queue_depth = g_hw_queue_depth;
+	tag_set.numa_node = g_home_node;
+	tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+	if (g_no_sched)
+		tag_set.flags |= BLK_MQ_F_NO_SCHED;
+	if (g_shared_tag_bitmap)
+		tag_set.flags |= BLK_MQ_F_TAG_HCTX_SHARED;
+	if (g_blocking)
+		tag_set.flags |= BLK_MQ_F_BLOCKING;
+
+	error = null_init_tag_set(&tag_set, g_poll_queues);
+	if (error)
+		tag_set.ops = NULL;
+	return error;
+}
+
+static int null_setup_tagset(struct nullb *nullb)
+{
+	if (nullb->dev->shared_tags) {
+		nullb->tag_set = &tag_set;
+		return null_init_global_tag_set();
+	}
+
+	nullb->tag_set = &nullb->__tag_set;
+	nullb->tag_set->driver_data = nullb;
+	nullb->tag_set->nr_hw_queues = nullb->dev->submit_queues;
+	nullb->tag_set->queue_depth = nullb->dev->hw_queue_depth;
+	nullb->tag_set->numa_node = nullb->dev->home_node;
+	nullb->tag_set->flags = BLK_MQ_F_SHOULD_MERGE;
+	if (nullb->dev->no_sched)
+		nullb->tag_set->flags |= BLK_MQ_F_NO_SCHED;
+	if (nullb->dev->shared_tag_bitmap)
+		nullb->tag_set->flags |= BLK_MQ_F_TAG_HCTX_SHARED;
+	if (nullb->dev->blocking)
+		nullb->tag_set->flags |= BLK_MQ_F_BLOCKING;
+	return null_init_tag_set(nullb->tag_set, nullb->dev->poll_queues);
+}
+
 static int null_validate_conf(struct nullb_device *dev)
 {
 	if (dev->queue_mode == NULL_Q_RQ) {
@@ -1904,21 +1914,7 @@ static int null_add_dev(struct nullb_device *dev)
 	if (rv)
 		goto out_free_nullb;
 
-	if (dev->shared_tags) {
-		if (!tag_set.ops) {
-			rv = null_init_tag_set(NULL, &tag_set);
-			if (rv) {
-				tag_set.ops = NULL;
-				goto out_cleanup_queues;
-			}
-		}
-		nullb->tag_set = &tag_set;
-		rv = 0;
-	} else {
-		nullb->tag_set = &nullb->__tag_set;
-		rv = null_init_tag_set(nullb, nullb->tag_set);
-	}
-
+	rv = null_setup_tagset(nullb);
 	if (rv)
 		goto out_cleanup_queues;
 
-- 
cgit v1.2.3


From 0a39e550c18244cdb9c4e671266a2a1d682d15c2 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Feb 2024 10:32:47 +0100
Subject: null_blk: remove null_gendisk_register

null_gendisk_register isn't a very useful abstraction given that it
doesn't even allocate the gendisk.  Merge it into the only caller
instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c | 41 ++++++++++++++++-------------------------
 1 file changed, 16 insertions(+), 25 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 03c3917a56fa..0c8d50423213 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1735,30 +1735,6 @@ static int setup_queues(struct nullb *nullb)
 	return 0;
 }
 
-static int null_gendisk_register(struct nullb *nullb)
-{
-	sector_t size = ((sector_t)nullb->dev->size * SZ_1M) >> SECTOR_SHIFT;
-	struct gendisk *disk = nullb->disk;
-
-	set_capacity(disk, size);
-
-	disk->major		= null_major;
-	disk->first_minor	= nullb->index;
-	disk->minors		= 1;
-	disk->fops		= &null_ops;
-	disk->private_data	= nullb;
-	strscpy_pad(disk->disk_name, nullb->disk_name, DISK_NAME_LEN);
-
-	if (nullb->dev->zoned) {
-		int ret = null_register_zoned_dev(nullb);
-
-		if (ret)
-			return ret;
-	}
-
-	return add_disk(disk);
-}
-
 static int null_init_tag_set(struct blk_mq_tag_set *set, int poll_queues)
 {
 	set->ops = &null_mq_ops;
@@ -1972,7 +1948,22 @@ static int null_add_dev(struct nullb_device *dev)
 		sprintf(nullb->disk_name, "nullb%d", nullb->index);
 	}
 
-	rv = null_gendisk_register(nullb);
+	set_capacity(nullb->disk,
+		((sector_t)nullb->dev->size * SZ_1M) >> SECTOR_SHIFT);
+	nullb->disk->major = null_major;
+	nullb->disk->first_minor = nullb->index;
+	nullb->disk->minors = 1;
+	nullb->disk->fops = &null_ops;
+	nullb->disk->private_data = nullb;
+	strscpy_pad(nullb->disk->disk_name, nullb->disk_name, DISK_NAME_LEN);
+
+	if (nullb->dev->zoned) {
+		rv = null_register_zoned_dev(nullb);
+		if (rv)
+			goto out_ida_free;
+	}
+
+	rv = add_disk(nullb->disk);
 	if (rv)
 		goto out_ida_free;
 
-- 
cgit v1.2.3


From e440626b1caf3767eda2d78610dfdc0ae7fd5238 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 20 Feb 2024 10:32:48 +0100
Subject: null_blk: pass queue_limits to blk_mq_alloc_disk

Pass the queue limits directly to blk_mq_alloc_disk instead of
setting them one at a time.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240220093248.3290292-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c     | 41 +++++++++++++++++++--------------------
 drivers/block/null_blk/null_blk.h |  4 ++--
 drivers/block/null_blk/zoned.c    | 15 +++++++-------
 3 files changed, 29 insertions(+), 31 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 0c8d50423213..a0b726c8366c 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1694,7 +1694,7 @@ static void null_del_dev(struct nullb *nullb)
 	dev->nullb = NULL;
 }
 
-static void null_config_discard(struct nullb *nullb)
+static void null_config_discard(struct nullb *nullb, struct queue_limits *lim)
 {
 	if (nullb->dev->discard == false)
 		return;
@@ -1711,7 +1711,7 @@ static void null_config_discard(struct nullb *nullb)
 		return;
 	}
 
-	blk_queue_max_discard_sectors(nullb->q, UINT_MAX >> 9);
+	lim->max_hw_discard_sectors = UINT_MAX >> 9;
 }
 
 static const struct block_device_operations null_ops = {
@@ -1869,6 +1869,12 @@ static bool null_setup_fault(void)
 
 static int null_add_dev(struct nullb_device *dev)
 {
+	struct queue_limits lim = {
+		.logical_block_size	= dev->blocksize,
+		.physical_block_size	= dev->blocksize,
+		.max_hw_sectors		= dev->max_sectors,
+	};
+
 	struct nullb *nullb;
 	int rv;
 
@@ -1894,10 +1900,19 @@ static int null_add_dev(struct nullb_device *dev)
 	if (rv)
 		goto out_cleanup_queues;
 
-	nullb->disk = blk_mq_alloc_disk(nullb->tag_set, NULL, nullb);
+	if (dev->virt_boundary)
+		lim.virt_boundary_mask = PAGE_SIZE - 1;
+	null_config_discard(nullb, &lim);
+	if (dev->zoned) {
+		rv = null_init_zoned_dev(dev, &lim);
+		if (rv)
+			goto out_cleanup_tags;
+	}
+
+	nullb->disk = blk_mq_alloc_disk(nullb->tag_set, &lim, nullb);
 	if (IS_ERR(nullb->disk)) {
 		rv = PTR_ERR(nullb->disk);
-		goto out_cleanup_tags;
+		goto out_cleanup_zone;
 	}
 	nullb->q = nullb->disk->queue;
 
@@ -1911,12 +1926,6 @@ static int null_add_dev(struct nullb_device *dev)
 		blk_queue_write_cache(nullb->q, true, true);
 	}
 
-	if (dev->zoned) {
-		rv = null_init_zoned_dev(dev, nullb->q);
-		if (rv)
-			goto out_cleanup_disk;
-	}
-
 	nullb->q->queuedata = nullb;
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, nullb->q);
 
@@ -1924,22 +1933,12 @@ static int null_add_dev(struct nullb_device *dev)
 	rv = ida_alloc(&nullb_indexes, GFP_KERNEL);
 	if (rv < 0) {
 		mutex_unlock(&lock);
-		goto out_cleanup_zone;
+		goto out_cleanup_disk;
 	}
 	nullb->index = rv;
 	dev->index = rv;
 	mutex_unlock(&lock);
 
-	blk_queue_logical_block_size(nullb->q, dev->blocksize);
-	blk_queue_physical_block_size(nullb->q, dev->blocksize);
-	if (dev->max_sectors)
-		blk_queue_max_hw_sectors(nullb->q, dev->max_sectors);
-
-	if (dev->virt_boundary)
-		blk_queue_virt_boundary(nullb->q, PAGE_SIZE - 1);
-
-	null_config_discard(nullb);
-
 	if (config_item_name(&dev->group.cg_item)) {
 		/* Use configfs dir name as the device name */
 		snprintf(nullb->disk_name, sizeof(nullb->disk_name),
diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h
index 7c618d53d8fd..25320fe34bfe 100644
--- a/drivers/block/null_blk/null_blk.h
+++ b/drivers/block/null_blk/null_blk.h
@@ -131,7 +131,7 @@ blk_status_t null_process_cmd(struct nullb_cmd *cmd, enum req_op op,
 			      sector_t sector, unsigned int nr_sectors);
 
 #ifdef CONFIG_BLK_DEV_ZONED
-int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q);
+int null_init_zoned_dev(struct nullb_device *dev, struct queue_limits *lim);
 int null_register_zoned_dev(struct nullb *nullb);
 void null_free_zoned_dev(struct nullb_device *dev);
 int null_report_zones(struct gendisk *disk, sector_t sector,
@@ -144,7 +144,7 @@ ssize_t zone_cond_store(struct nullb_device *dev, const char *page,
 			size_t count, enum blk_zone_cond cond);
 #else
 static inline int null_init_zoned_dev(struct nullb_device *dev,
-				      struct request_queue *q)
+		struct queue_limits *lim)
 {
 	pr_err("CONFIG_BLK_DEV_ZONED not enabled\n");
 	return -EINVAL;
diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c
index 3605afe105da..1689e2584104 100644
--- a/drivers/block/null_blk/zoned.c
+++ b/drivers/block/null_blk/zoned.c
@@ -58,7 +58,8 @@ static inline void null_unlock_zone(struct nullb_device *dev,
 		mutex_unlock(&zone->mutex);
 }
 
-int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
+int null_init_zoned_dev(struct nullb_device *dev,
+			struct queue_limits *lim)
 {
 	sector_t dev_capacity_sects, zone_capacity_sects;
 	struct nullb_zone *zone;
@@ -151,23 +152,21 @@ int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q)
 		sector += dev->zone_size_sects;
 	}
 
+	lim->zoned = true;
+	lim->chunk_sectors = dev->zone_size_sects;
+	lim->max_zone_append_sectors = dev->zone_size_sects;
+	lim->max_open_zones = dev->zone_max_open;
+	lim->max_active_zones = dev->zone_max_active;
 	return 0;
 }
 
 int null_register_zoned_dev(struct nullb *nullb)
 {
-	struct nullb_device *dev = nullb->dev;
 	struct request_queue *q = nullb->q;
 
-	disk_set_zoned(nullb->disk);
 	blk_queue_flag_set(QUEUE_FLAG_ZONE_RESETALL, q);
 	blk_queue_required_elevator_features(q, ELEVATOR_F_ZBD_SEQ_WRITE);
-	blk_queue_chunk_sectors(q, dev->zone_size_sects);
 	nullb->disk->nr_zones = bdev_nr_zones(nullb->disk->part0);
-	blk_queue_max_zone_append_sectors(q, dev->zone_size_sects);
-	disk_set_max_open_zones(nullb->disk, dev->zone_max_open);
-	disk_set_max_active_zones(nullb->disk, dev->zone_max_active);
-
 	return blk_revalidate_disk_zones(nullb->disk, NULL);
 }
 
-- 
cgit v1.2.3


From 0f225f87873ee95dd4cf94dfc6a3249d4289e4ea Mon Sep 17 00:00:00 2001
From: John Garry <john.g.garry@oracle.com>
Date: Thu, 22 Feb 2024 08:34:20 +0000
Subject: null_blk: Delete nullb.{queue_depth, nr_queues}

Since commit 8b631f9cf0b8 ("null_blk: remove the bio based I/O path"),
struct nullb members queue_depth and nr_queues are only ever written, so
delete them.

With that, null_exit_hctx() can also be deleted.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240222083420.6026-1-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 drivers/block/null_blk/main.c     | 11 -----------
 drivers/block/null_blk/null_blk.h |  2 --
 2 files changed, 13 deletions(-)

(limited to 'drivers/block/null_blk/main.c')

diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index a0b726c8366c..71c39bcd872c 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1620,14 +1620,6 @@ static void null_queue_rqs(struct request **rqlist)
 	*rqlist = requeue_list;
 }
 
-static void null_exit_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
-{
-	struct nullb_queue *nq = hctx->driver_data;
-	struct nullb *nullb = nq->dev->nullb;
-
-	nullb->nr_queues--;
-}
-
 static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq)
 {
 	nq->dev = nullb->dev;
@@ -1647,7 +1639,6 @@ static int null_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data,
 	nq = &nullb->queues[hctx_idx];
 	hctx->driver_data = nq;
 	null_init_queue(nullb, nq);
-	nullb->nr_queues++;
 
 	return 0;
 }
@@ -1660,7 +1651,6 @@ static const struct blk_mq_ops null_mq_ops = {
 	.poll		= null_poll,
 	.map_queues	= null_map_queues,
 	.init_hctx	= null_init_hctx,
-	.exit_hctx	= null_exit_hctx,
 };
 
 static void null_del_dev(struct nullb *nullb)
@@ -1731,7 +1721,6 @@ static int setup_queues(struct nullb *nullb)
 	if (!nullb->queues)
 		return -ENOMEM;
 
-	nullb->queue_depth = nullb->dev->hw_queue_depth;
 	return 0;
 }
 
diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h
index 25320fe34bfe..477b97746823 100644
--- a/drivers/block/null_blk/null_blk.h
+++ b/drivers/block/null_blk/null_blk.h
@@ -114,14 +114,12 @@ struct nullb {
 	struct gendisk *disk;
 	struct blk_mq_tag_set *tag_set;
 	struct blk_mq_tag_set __tag_set;
-	unsigned int queue_depth;
 	atomic_long_t cur_bytes;
 	struct hrtimer bw_timer;
 	unsigned long cache_flush_pos;
 	spinlock_t lock;
 
 	struct nullb_queue *queues;
-	unsigned int nr_queues;
 	char disk_name[DISK_NAME_LEN];
 };
 
-- 
cgit v1.2.3