block: move the nonrot flag to queue_limits

Move the nonrot flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.

Use the chance to switch to defaulting to non-rotational and require
the driver to opt into rotational, which matches the polarity of the
sysfs interface.

For the z2ram, ps3vram, 2x memstick, ubiblock and dcssblk the new
rotational flag is not set as they clearly are not rotational despite
this being a behavior change.  There are some other drivers that
unconditionally set the rotational flag to keep the existing behavior
as they arguably can be used on rotational devices even if that is
probably not their main use today (e.g. virtio_blk and drbd).

The flag is automatically inherited in blk_stack_limits matching the
existing behavior in dm and md.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

22 files changed, 34 insertions, 40 deletions

diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index a25414228e47..ff45701f7a5e 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -1776,10 +1776,13 @@ static const struct blk_mq_ops amiflop_mq_ops = {
 
 static int fd_alloc_disk(int drive, int system)
 {
+	struct queue_limits lim = {
+		.features		= BLK_FEAT_ROTATIONAL,
+	};
 	struct gendisk *disk;
 	int err;
 
-	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL, NULL);
+	disk = blk_mq_alloc_disk(&unit[drive].tag_set, &lim, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index b6dac8cee70f..2028795ec61c 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -337,6 +337,7 @@ aoeblk_gdalloc(void *vp)
 	struct queue_limits lim = {
 		.max_hw_sectors		= aoe_maxsectors,
 		.io_opt			= SZ_2M,
+		.features		= BLK_FEAT_ROTATIONAL,
 	};
 	ulong flags;
 	int late = 0;
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index cacc4ba942a8..4ee10a742bdb 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1992,9 +1992,12 @@ static const struct blk_mq_ops ataflop_mq_ops = {
 
 static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
 {
+	struct queue_limits lim = {
+		.features		= BLK_FEAT_ROTATIONAL,
+	};
 	struct gendisk *disk;
 
-	disk = blk_mq_alloc_disk(&unit[drive].tag_set, NULL, NULL);
+	disk = blk_mq_alloc_disk(&unit[drive].tag_set, &lim, NULL);
 	if (IS_ERR(disk))
 		return PTR_ERR(disk);
 
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 558d8e670566..b25dc463b5e3 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -366,8 +366,6 @@ static int brd_alloc(int i)
 	strscpy(disk->disk_name, buf, DISK_NAME_LEN);
 	set_capacity(disk, rd_size * 2);
 	
-	/* Tell the block layer that this is not a rotational device */
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
 	blk_queue_flag_set(QUEUE_FLAG_SYNCHRONOUS, disk->queue);
 	blk_queue_flag_set(QUEUE_FLAG_NOWAIT, disk->queue);
 	err = add_disk(disk);
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index bf42a46781fa..2ef29a478075 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2697,7 +2697,8 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig
 		 * connect.
 		 */
 		.max_hw_sectors		= DRBD_MAX_BIO_SIZE_SAFE >> 8,
-		.features		= BLK_FEAT_WRITE_CACHE | BLK_FEAT_FUA,
+		.features		= BLK_FEAT_WRITE_CACHE | BLK_FEAT_FUA |
+					  BLK_FEAT_ROTATIONAL,
 	};
 
 	device = minor_to_device(minor);
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 25c9d85667f1..6d7f7df97c3a 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4516,7 +4516,8 @@ static bool floppy_available(int drive)
 static int floppy_alloc_disk(unsigned int drive, unsigned int type)
 {
 	struct queue_limits lim = {
-		.max_hw_sectors = 64,
+		.max_hw_sectors		= 64,
+		.features		= BLK_FEAT_ROTATIONAL,
 	};
 	struct gendisk *disk;
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 08d0fc7f17b7..86b5d956dc4e 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -985,13 +985,11 @@ static int loop_reconfigure_limits(struct loop_device *lo, unsigned short bsize)
 	lim.logical_block_size = bsize;
 	lim.physical_block_size = bsize;
 	lim.io_min = bsize;
-	lim.features &= ~BLK_FEAT_WRITE_CACHE;
+	lim.features &= ~(BLK_FEAT_WRITE_CACHE | BLK_FEAT_ROTATIONAL);
 	if (file->f_op->fsync && !(lo->lo_flags & LO_FLAGS_READ_ONLY))
 		lim.features |= BLK_FEAT_WRITE_CACHE;
-	if (!backing_bdev || bdev_nonrot(backing_bdev))
-		blk_queue_flag_set(QUEUE_FLAG_NONROT, lo->lo_queue);
-	else
-		blk_queue_flag_clear(QUEUE_FLAG_NONROT, lo->lo_queue);
+	if (backing_bdev && !bdev_nonrot(backing_bdev))
+		lim.features |= BLK_FEAT_ROTATIONAL;
 	loop_config_discard(lo, &lim);
 	return queue_limits_commit_update(lo->lo_queue, &lim);
 }
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 43a187609ef7..1dbbf72659d5 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3485,7 +3485,6 @@ skip_create_disk:
 		goto start_service_thread;
 
 	/* Set device limits. */
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, dd->queue);
 	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, dd->queue);
 	dma_set_max_seg_size(&dd->pdev->dev, 0x400000);
 
diff --git a/drivers/block/n64cart.c b/drivers/block/n64cart.c
index 27b2187e7a6d..b9fdeff31caf 100644
--- a/drivers/block/n64cart.c
+++ b/drivers/block/n64cart.c
@@ -150,8 +150,6 @@ static int __init n64cart_probe(struct platform_device *pdev)
 	set_capacity(disk, size >> SECTOR_SHIFT);
 	set_disk_ro(disk, 1);
 
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
-
 	err = add_disk(disk);
 	if (err)
 		goto out_cleanup_disk;
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index cb1c86a6a3fb..6cddf5baffe0 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1867,11 +1867,6 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 		goto out_err_disk;
 	}
 
-	/*
-	 * Tell the block layer that we are not a rotational device
-	 */
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
-
 	mutex_init(&nbd->config_lock);
 	refcount_set(&nbd->config_refs, 0);
 	/*
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c
index 21f9d256e884..83a4ebe4763a 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1948,7 +1948,6 @@ static int null_add_dev(struct nullb_device *dev)
 	}
 
 	nullb->q->queuedata = nullb;
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, nullb->q);
 
 	rv = ida_alloc(&nullb_indexes, GFP_KERNEL);
 	if (rv < 0)
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 8a2ce8070010..7cece5884b9c 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2622,6 +2622,7 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	struct queue_limits lim = {
 		.max_hw_sectors		= PACKET_MAX_SECTORS,
 		.logical_block_size	= CD_FRAMESIZE,
+		.features		= BLK_FEAT_ROTATIONAL,
 	};
 	int idx;
 	int ret = -ENOMEM;
diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
index 8b73cf459b59..ff45ed766469 100644
--- a/drivers/block/ps3disk.c
+++ b/drivers/block/ps3disk.c
@@ -388,7 +388,8 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 		.max_segments		= -1,
 		.max_segment_size	= dev->bounce_size,
 		.dma_alignment		= dev->blk_size - 1,
-		.features		= BLK_FEAT_WRITE_CACHE,
+		.features		= BLK_FEAT_WRITE_CACHE |
+					  BLK_FEAT_ROTATIONAL,
 	};
 	struct gendisk *gendisk;
 
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 22ad704f81d8..ec1f1c7d4275 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -4997,9 +4997,6 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
 	disk->fops = &rbd_bd_ops;
 	disk->private_data = rbd_dev;
 
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
-	/* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
-
 	if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
 		blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
 
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 02c4b1731827..4918b0f68b46 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -1352,10 +1352,6 @@ static int rnbd_clt_setup_gen_disk(struct rnbd_clt_dev *dev,
 	if (dev->access_mode == RNBD_ACCESS_RO)
 		set_disk_ro(dev->gd, true);
 
-	/*
-	 * Network device does not need rotational
-	 */
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, dev->queue);
 	err = add_disk(dev->gd);
 	if (err)
 		put_disk(dev->gd);
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index 5286cb8e0824..2d38331ee667 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -791,6 +791,7 @@ static int probe_disk(struct vdc_port *port)
 		.seg_boundary_mask		= PAGE_SIZE - 1,
 		.max_segment_size		= PAGE_SIZE,
 		.max_segments			= port->ring_cookies,
+		.features			= BLK_FEAT_ROTATIONAL,
 	};
 	struct request_queue *q;
 	struct gendisk *g;
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 6731678f3a41..126f151c4f2c 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -787,6 +787,9 @@ static void swim_cleanup_floppy_disk(struct floppy_state *fs)
 
 static int swim_floppy_init(struct swim_priv *swd)
 {
+	struct queue_limits lim = {
+		.features		= BLK_FEAT_ROTATIONAL,
+	};
 	int err;
 	int drive;
 	struct swim __iomem *base = swd->base;
@@ -820,7 +823,7 @@ 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, NULL,
+			blk_mq_alloc_disk(&swd->unit[drive].tag_set, &lim,
 					  &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 a04756ac778e..90be1017f7bf 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -1189,6 +1189,9 @@ static int swim3_add_device(struct macio_dev *mdev, int index)
 static int swim3_attach(struct macio_dev *mdev,
 			const struct of_device_id *match)
 {
+	struct queue_limits lim = {
+		.features		= BLK_FEAT_ROTATIONAL,
+	};
 	struct floppy_state *fs;
 	struct gendisk *disk;
 	int rc;
@@ -1210,7 +1213,7 @@ static int swim3_attach(struct macio_dev *mdev,
 	if (rc)
 		goto out_unregister;
 
-	disk = blk_mq_alloc_disk(&fs->tag_set, NULL, fs);
+	disk = blk_mq_alloc_disk(&fs->tag_set, &lim, 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 e45c65c1848d..4fcde0999358 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -484,14 +484,8 @@ static inline unsigned ublk_pos_to_tag(loff_t pos)
 
 static void ublk_dev_param_basic_apply(struct ublk_device *ub)
 {
-	struct request_queue *q = ub->ub_disk->queue;
 	const struct ublk_param_basic *p = &ub->params.basic;
 
-	if (p->attrs & UBLK_ATTR_ROTATIONAL)
-		blk_queue_flag_clear(QUEUE_FLAG_NONROT, q);
-	else
-		blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
-
 	if (p->attrs & UBLK_ATTR_READ_ONLY)
 		set_disk_ro(ub->ub_disk, true);
 
@@ -2214,6 +2208,9 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd)
 			lim.features |= BLK_FEAT_FUA;
 	}
 
+	if (ub->params.basic.attrs & UBLK_ATTR_ROTATIONAL)
+		lim.features |= BLK_FEAT_ROTATIONAL;
+
 	if (wait_for_completion_interruptible(&ub->completion) != 0)
 		return -EINTR;
 
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index b1a3c2935285..13a2f24f1766 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -1451,7 +1451,9 @@ static int virtblk_read_limits(struct virtio_blk *vblk,
 static int virtblk_probe(struct virtio_device *vdev)
 {
 	struct virtio_blk *vblk;
-	struct queue_limits lim = { };
+	struct queue_limits lim = {
+		.features		= BLK_FEAT_ROTATIONAL,
+	};
 	int err, index;
 	unsigned int queue_depth;
 
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 9aafce3e5987..fa3a2ba52545 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1146,7 +1146,6 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 		err = PTR_ERR(gd);
 		goto out_free_tag_set;
 	}
-	blk_queue_flag_set(QUEUE_FLAG_VIRT, gd->queue);
 
 	strcpy(gd->disk_name, DEV_NAME);
 	ptr = encode_disk_name(gd->disk_name + sizeof(DEV_NAME) - 1, offset);
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 3acd7006ad2c..aad840fc7e18 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -2245,8 +2245,6 @@ static int zram_add(void)
 
 	/* Actual capacity set using sysfs (/sys/block/zram<id>/disksize */
 	set_capacity(zram->disk, 0);
-	/* zram devices sort of resembles non-rotational disks */
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, zram->disk->queue);
 	blk_queue_flag_set(QUEUE_FLAG_SYNCHRONOUS, zram->disk->queue);
 	blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, zram->disk->queue);
 	ret = device_add_disk(NULL, zram->disk, zram_disk_groups);