Merge tag 'for-6.4/block-2023-05-06' of git://git.kernel.dk/linux

Pull more block updates from Jens Axboe:

- MD pull request via Song:
- Improve raid5 sequential IO performance on spinning disks, which
fixes a regression since v6.0 (Jan Kara)
- Fix bitmap offset types, which fixes an issue introduced in this
merge window (Jonathan Derrick)

- Cleanup of hweight type used for cgroup writeback (Maxim)

- Fix a regression with the "has_submit_bio" changes across partitions
(Ming)

- Cleanup of QUEUE_FLAG_ADD_RANDOM clearing.

We used to set this flag on queues non blk-mq queues, and hence some
drivers clear it unconditionally. Since all of these have since been
converted to true blk-mq drivers, drop the useless clear as the bit
is not set (Chaitanya)

- Fix the flags being set in a bio for a flush for drbd (Christoph)

- Cleanup and deduplication of the code handling setting block device
capacity (Damien)

- Fix for ublk handling IO timeouts (Ming)

- Fix for a regression in blk-cgroup teardown (Tao)

- NBD documentation and code fixes (Eric)

- Convert blk-integrity to using device_attributes rather than a second
kobject to manage lifetimes (Thomas)

* tag 'for-6.4/block-2023-05-06' of git://git.kernel.dk/linux:
ublk: add timeout handler
drbd: correctly submit flush bio on barrier
mailmap: add mailmap entries for Jens Axboe
block: Skip destroyed blkg when restart in blkg_destroy_all()
writeback: fix call of incorrect macro
md: Fix bitmap offset type in sb writer
md/raid5: Improve performance for sequential IO
docs nbd: userspace NBD now favors github over sourceforge
block nbd: use req.cookie instead of req.handle
uapi nbd: add cookie alias to handle
uapi nbd: improve doc links to userspace spec
blk-integrity: register sysfs attributes on struct device
blk-integrity: convert to struct device_attribute
blk-integrity: use sysfs_emit
block/drivers: remove dead clear of random flag
block: sync part's ->bd_has_submit_bio with disk's
block: Cleanup set_capacity()/bdev_set_nr_sectors()

.mailmap

···
 Jeff Layton <[e-mail]> <[e-mail]>
 Jeff Layton <[e-mail]> <[e-mail]>
 Jeff Layton <[e-mail]> <[e-mail]>
-Jens Axboe <[e-mail]>
+Jens Axboe <[e-mail]> <[e-mail]>
+Jens Axboe <[e-mail]> <[e-mail]>
+Jens Axboe <[e-mail]> <[e-mail]>
+Jens Axboe <[e-mail]> <[e-mail]>
 Jens Osterkamp <[e-mail]>
 Jernej Skrabec <[e-mail]> <[e-mail]>
 Jessica Zhang <[e-mail]> <[e-mail]>

Documentation/admin-guide/blockdev/nbd.rst

···
 Unlike NFS, it is possible to put any filesystem on it, etc.
 
 For more information, or to download the nbd-client and nbd-server
-tools, go to http://nbd.sf.net/.
+tools, go to https://github.com/NetworkBlockDevice/nbd.
 
 The nbd kernel module need only be installed on the client
 system, as the nbd-server is completely in userspace. In fact,

block/bdev.c

···
 	bdev->bd_partno = partno;
 	bdev->bd_inode = inode;
 	bdev->bd_queue = disk->queue;
+	if (partno)
+		bdev->bd_has_submit_bio = disk->part0->bd_has_submit_bio;
+	else
+		bdev->bd_has_submit_bio = false;
 	bdev->bd_stats = alloc_percpu(struct disk_stats);
-	bdev->bd_has_submit_bio = false;
 	if (!bdev->bd_stats) {
 		iput(inode);
 		return NULL;
 	}
 	bdev->bd_disk = disk;
 	return bdev;
+}
+
+void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors)
+{
+	spin_lock(&bdev->bd_size_lock);
+	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
+	bdev->bd_nr_sectors = sectors;
+	spin_unlock(&bdev->bd_size_lock);
 }
 
 void bdev_add(struct block_device *bdev, dev_t dev)

block/blk-cgroup.c

···
 	list_for_each_entry_safe(blkg, n, &q->blkg_list, q_node) {
 		struct blkcg *blkcg = blkg->blkcg;
 
+		if (hlist_unhashed(&blkg->blkcg_node))
+			continue;
+
 		spin_lock(&blkcg->lock);
 		blkg_destroy(blkg);
 		spin_unlock(&blkcg->lock);

block/blk-integrity.c

···
 	return true;
 }
 
-struct integrity_sysfs_entry {
-	struct attribute attr;
-	ssize_t (*show)(struct blk_integrity *, char *);
-	ssize_t (*store)(struct blk_integrity *, const char *, size_t);
-};
-
-static ssize_t integrity_attr_show(struct kobject *kobj, struct attribute *attr,
-				   char *page)
+static inline struct blk_integrity *dev_to_bi(struct device *dev)
 {
-	struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
-	struct blk_integrity *bi = &disk->queue->integrity;
-	struct integrity_sysfs_entry *entry =
-		container_of(attr, struct integrity_sysfs_entry, attr);
-
-	return entry->show(bi, page);
+	return &dev_to_disk(dev)->queue->integrity;
 }
 
-static ssize_t integrity_attr_store(struct kobject *kobj,
-				    struct attribute *attr, const char *page,
-				    size_t count)
+static ssize_t format_show(struct device *dev, struct device_attribute *attr,
+			   char *page)
 {
-	struct gendisk *disk = container_of(kobj, struct gendisk, integrity_kobj);
-	struct blk_integrity *bi = &disk->queue->integrity;
-	struct integrity_sysfs_entry *entry =
-		container_of(attr, struct integrity_sysfs_entry, attr);
-	ssize_t ret = 0;
+	struct blk_integrity *bi = dev_to_bi(dev);
 
-	if (entry->store)
-		ret = entry->store(bi, page, count);
-
-	return ret;
-}
-
-static ssize_t integrity_format_show(struct blk_integrity *bi, char *page)
-{
 	if (bi->profile && bi->profile->name)
-		return sprintf(page, "%s\n", bi->profile->name);
-	else
-		return sprintf(page, "none\n");
+		return sysfs_emit(page, "%s\n", bi->profile->name);
+	return sysfs_emit(page, "none\n");
 }
 
-static ssize_t integrity_tag_size_show(struct blk_integrity *bi, char *page)
+static ssize_t tag_size_show(struct device *dev, struct device_attribute *attr,
+			     char *page)
 {
-	return sprintf(page, "%u\n", bi->tag_size);
+	struct blk_integrity *bi = dev_to_bi(dev);
+
+	return sysfs_emit(page, "%u\n", bi->tag_size);
 }
 
-static ssize_t integrity_interval_show(struct blk_integrity *bi, char *page)
+static ssize_t protection_interval_bytes_show(struct device *dev,
+					      struct device_attribute *attr,
+					      char *page)
 {
-	return sprintf(page, "%u\n",
-		       bi->interval_exp ? 1 << bi->interval_exp : 0);
+	struct blk_integrity *bi = dev_to_bi(dev);
+
+	return sysfs_emit(page, "%u\n",
+			  bi->interval_exp ? 1 << bi->interval_exp : 0);
 }
 
-static ssize_t integrity_verify_store(struct blk_integrity *bi,
-				      const char *page, size_t count)
+static ssize_t read_verify_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *page, size_t count)
 {
+	struct blk_integrity *bi = dev_to_bi(dev);
 	char *p = (char *) page;
 	unsigned long val = simple_strtoul(p, &p, 10);
 
···
 	return count;
 }
 
-static ssize_t integrity_verify_show(struct blk_integrity *bi, char *page)
+static ssize_t read_verify_show(struct device *dev,
+				struct device_attribute *attr, char *page)
 {
-	return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_VERIFY) != 0);
+	struct blk_integrity *bi = dev_to_bi(dev);
+
+	return sysfs_emit(page, "%d\n", !!(bi->flags & BLK_INTEGRITY_VERIFY));
 }
 
-static ssize_t integrity_generate_store(struct blk_integrity *bi,
-					const char *page, size_t count)
+static ssize_t write_generate_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *page, size_t count)
 {
+	struct blk_integrity *bi = dev_to_bi(dev);
+
 	char *p = (char *) page;
 	unsigned long val = simple_strtoul(p, &p, 10);
 
···
 	return count;
 }
 
-static ssize_t integrity_generate_show(struct blk_integrity *bi, char *page)
+static ssize_t write_generate_show(struct device *dev,
+				   struct device_attribute *attr, char *page)
 {
-	return sprintf(page, "%d\n", (bi->flags & BLK_INTEGRITY_GENERATE) != 0);
+	struct blk_integrity *bi = dev_to_bi(dev);
+
+	return sysfs_emit(page, "%d\n", !!(bi->flags & BLK_INTEGRITY_GENERATE));
 }
 
-static ssize_t integrity_device_show(struct blk_integrity *bi, char *page)
+static ssize_t device_is_integrity_capable_show(struct device *dev,
+						struct device_attribute *attr,
+						char *page)
 {
-	return sprintf(page, "%u\n",
-		       (bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE) != 0);
+	struct blk_integrity *bi = dev_to_bi(dev);
+
+	return sysfs_emit(page, "%u\n",
+			  !!(bi->flags & BLK_INTEGRITY_DEVICE_CAPABLE));
 }
 
-static struct integrity_sysfs_entry integrity_format_entry = {
-	.attr = { .name = "format", .mode = 0444 },
-	.show = integrity_format_show,
-};
-
-static struct integrity_sysfs_entry integrity_tag_size_entry = {
-	.attr = { .name = "tag_size", .mode = 0444 },
-	.show = integrity_tag_size_show,
-};
-
-static struct integrity_sysfs_entry integrity_interval_entry = {
-	.attr = { .name = "protection_interval_bytes", .mode = 0444 },
-	.show = integrity_interval_show,
-};
-
-static struct integrity_sysfs_entry integrity_verify_entry = {
-	.attr = { .name = "read_verify", .mode = 0644 },
-	.show = integrity_verify_show,
-	.store = integrity_verify_store,
-};
-
-static struct integrity_sysfs_entry integrity_generate_entry = {
-	.attr = { .name = "write_generate", .mode = 0644 },
-	.show = integrity_generate_show,
-	.store = integrity_generate_store,
-};
-
-static struct integrity_sysfs_entry integrity_device_entry = {
-	.attr = { .name = "device_is_integrity_capable", .mode = 0444 },
-	.show = integrity_device_show,
-};
+static DEVICE_ATTR_RO(format);
+static DEVICE_ATTR_RO(tag_size);
+static DEVICE_ATTR_RO(protection_interval_bytes);
+static DEVICE_ATTR_RW(read_verify);
+static DEVICE_ATTR_RW(write_generate);
+static DEVICE_ATTR_RO(device_is_integrity_capable);
 
 static struct attribute *integrity_attrs[] = {
-	&integrity_format_entry.attr,
-	&integrity_tag_size_entry.attr,
-	&integrity_interval_entry.attr,
-	&integrity_verify_entry.attr,
-	&integrity_generate_entry.attr,
-	&integrity_device_entry.attr,
-	NULL,
-};
-ATTRIBUTE_GROUPS(integrity);
-
-static const struct sysfs_ops integrity_ops = {
-	.show	= &integrity_attr_show,
-	.store	= &integrity_attr_store,
+	&dev_attr_format.attr,
+	&dev_attr_tag_size.attr,
+	&dev_attr_protection_interval_bytes.attr,
+	&dev_attr_read_verify.attr,
+	&dev_attr_write_generate.attr,
+	&dev_attr_device_is_integrity_capable.attr,
+	NULL
 };
 
-static const struct kobj_type integrity_ktype = {
-	.default_groups = integrity_groups,
-	.sysfs_ops	= &integrity_ops,
+const struct attribute_group blk_integrity_attr_group = {
+	.name = "integrity",
+	.attrs = integrity_attrs,
 };
 
 static blk_status_t blk_integrity_nop_fn(struct blk_integrity_iter *iter)
···
 	memset(bi, 0, sizeof(*bi));
 }
 EXPORT_SYMBOL(blk_integrity_unregister);
-
-int blk_integrity_add(struct gendisk *disk)
-{
-	int ret;
-
-	ret = kobject_init_and_add(&disk->integrity_kobj, &integrity_ktype,
-				   &disk_to_dev(disk)->kobj, "%s", "integrity");
-	if (!ret)
-		kobject_uevent(&disk->integrity_kobj, KOBJ_ADD);
-	return ret;
-}
-
-void blk_integrity_del(struct gendisk *disk)
-{
-	kobject_uevent(&disk->integrity_kobj, KOBJ_REMOVE);
-	kobject_del(&disk->integrity_kobj);
-	kobject_put(&disk->integrity_kobj);
-}

block/blk.h

···
 				bip_next->bip_vec[0].bv_offset);
 }
 
-int blk_integrity_add(struct gendisk *disk);
-void blk_integrity_del(struct gendisk *);
+extern const struct attribute_group blk_integrity_attr_group;
 #else /* CONFIG_BLK_DEV_INTEGRITY */
 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
 		struct request *r1, struct request *r2)
···
 	return true;
 }
 static inline void bio_integrity_free(struct bio *bio)
-{
-}
-static inline int blk_integrity_add(struct gendisk *disk)
-{
-	return 0;
-}
-static inline void blk_integrity_del(struct gendisk *disk)
 {
 }
 #endif /* CONFIG_BLK_DEV_INTEGRITY */
···
 int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
 		sector_t length);
 void blk_drop_partitions(struct gendisk *disk);
+
+void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors);
 
 struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
 		struct lock_class_key *lkclass);

block/genhd.c

···
 
 void set_capacity(struct gendisk *disk, sector_t sectors)
 {
-	struct block_device *bdev = disk->part0;
-
-	spin_lock(&bdev->bd_size_lock);
-	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
-	bdev->bd_nr_sectors = sectors;
-	spin_unlock(&bdev->bd_size_lock);
+	bdev_set_nr_sectors(disk->part0, sectors);
 }
 EXPORT_SYMBOL(set_capacity);
 
···
 	 */
 	pm_runtime_set_memalloc_noio(ddev, true);
 
-	ret = blk_integrity_add(disk);
-	if (ret)
-		goto out_del_block_link;
-
 	disk->part0->bd_holder_dir =
 		kobject_create_and_add("holders", &ddev->kobj);
 	if (!disk->part0->bd_holder_dir) {
 		ret = -ENOMEM;
-		goto out_del_integrity;
+		goto out_del_block_link;
 	}
 	disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
 	if (!disk->slave_dir) {
···
 	disk->slave_dir = NULL;
 out_put_holder_dir:
 	kobject_put(disk->part0->bd_holder_dir);
-out_del_integrity:
-	blk_integrity_del(disk);
 out_del_block_link:
 	sysfs_remove_link(block_depr, dev_name(ddev));
 out_device_del:
···
 	if (WARN_ON_ONCE(!disk_live(disk) && !(disk->flags & GENHD_FL_HIDDEN)))
 		return;
 
-	blk_integrity_del(disk);
 	disk_del_events(disk);
 
 	mutex_lock(&disk->open_mutex);
···
 	&disk_attr_group,
 #ifdef CONFIG_BLK_DEV_IO_TRACE
 	&blk_trace_attr_group,
+#endif
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+	&blk_integrity_attr_group,
 #endif
 	NULL
 };

block/partitions/core.c

···
 	NULL
 };
 
-static void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors)
-{
-	spin_lock(&bdev->bd_size_lock);
-	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
-	bdev->bd_nr_sectors = sectors;
-	spin_unlock(&bdev->bd_size_lock);
-}
-
 static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
 {
 	struct parsed_partitions *state;

drivers/block/brd.c

···
 	/* 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_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
 	blk_queue_flag_set(QUEUE_FLAG_NOWAIT, disk->queue);
 	err = add_disk(disk);
 	if (err)

drivers/block/drbd/drbd_receiver.c

···
 static void submit_one_flush(struct drbd_device *device, struct issue_flush_context *ctx)
 {
 	struct bio *bio = bio_alloc(device->ldev->backing_bdev, 0,
-				    REQ_OP_FLUSH | REQ_PREFLUSH, GFP_NOIO);
+				    REQ_OP_WRITE | REQ_PREFLUSH, GFP_NOIO);
 	struct one_flush_context *octx = kmalloc(sizeof(*octx), GFP_NOIO);
 
 	if (!octx) {

drivers/block/nbd.c

···
 		request.len = htonl(size);
 	}
 	handle = nbd_cmd_handle(cmd);
-	memcpy(request.handle, &handle, sizeof(handle));
+	request.cookie = cpu_to_be64(handle);
 
 	trace_nbd_send_request(&request, nbd->index, blk_mq_rq_from_pdu(cmd));
 
···
 	trace_nbd_header_sent(req, handle);
 	if (result < 0) {
 		if (was_interrupted(result)) {
-			/* If we havne't sent anything we can just return BUSY,
+			/* If we haven't sent anything we can just return BUSY,
 			 * however if we have sent something we need to make
 			 * sure we only allow this req to be sent until we are
 			 * completely done.
···
 	u32 tag;
 	int ret = 0;
 
-	memcpy(&handle, reply->handle, sizeof(handle));
+	handle = be64_to_cpu(reply->cookie);
 	tag = nbd_handle_to_tag(handle);
 	hwq = blk_mq_unique_tag_to_hwq(tag);
 	if (hwq < nbd->tag_set.nr_hw_queues)
···
 	 * Tell the block layer that we are not a rotational device
 	 */
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
-	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
 	disk->queue->limits.discard_granularity = 0;
 	blk_queue_max_discard_sectors(disk->queue, 0);
 	blk_queue_max_segment_size(disk->queue, UINT_MAX);

drivers/block/null_blk/main.c

···
 
 	nullb->q->queuedata = nullb;
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, nullb->q);
-	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, nullb->q);
 
 	mutex_lock(&lock);
 	rv = ida_simple_get(&nullb_indexes, 0, 0, GFP_KERNEL);

drivers/block/ublk_drv.c

···
 	unsigned long io_addr;	/* mapped vm address */
 	unsigned int max_io_sz;
 	bool force_abort;
+	bool timeout;
 	unsigned short nr_io_ready;	/* how many ios setup */
 	struct ublk_device *dev;
 	struct ublk_io ios[];
···
 	}
 }
 
+static enum blk_eh_timer_return ublk_timeout(struct request *rq)
+{
+	struct ublk_queue *ubq = rq->mq_hctx->driver_data;
+
+	if (ubq->flags & UBLK_F_UNPRIVILEGED_DEV) {
+		if (!ubq->timeout) {
+			send_sig(SIGKILL, ubq->ubq_daemon, 0);
+			ubq->timeout = true;
+		}
+
+		return BLK_EH_DONE;
+	}
+
+	return BLK_EH_RESET_TIMER;
+}
+
 static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
 		const struct blk_mq_queue_data *bd)
 {
···
 	.queue_rq       = ublk_queue_rq,
 	.init_hctx	= ublk_init_hctx,
 	.init_request   = ublk_init_rq,
+	.timeout	= ublk_timeout,
 };
 
 static int ublk_ch_open(struct inode *inode, struct file *filp)
···
 	else if (!(info.flags & UBLK_F_UNPRIVILEGED_DEV))
 		return -EPERM;
 
+	/*
+	 * unprivileged device can't be trusted, but RECOVERY and
+	 * RECOVERY_REISSUE still may hang error handling, so can't
+	 * support recovery features for unprivileged ublk now
+	 *
+	 * TODO: provide forward progress for RECOVERY handler, so that
+	 * unprivileged device can benefit from it
+	 */
+	if (info.flags & UBLK_F_UNPRIVILEGED_DEV)
+		info.flags &= ~(UBLK_F_USER_RECOVERY_REISSUE |
+				UBLK_F_USER_RECOVERY);
+
 	/* the created device is always owned by current user */
 	ublk_store_owner_uid_gid(&info.owner_uid, &info.owner_gid);
 
···
 	put_task_struct(ubq->ubq_daemon);
 	/* We have to reset it to NULL, otherwise ub won't accept new FETCH_REQ */
 	ubq->ubq_daemon = NULL;
+	ubq->timeout = false;
 
 	for (i = 0; i < ubq->q_depth; i++) {
 		struct ublk_io *io = &ubq->ios[i];

drivers/block/zram/zram_drv.c

···
 	/* 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_clear(QUEUE_FLAG_ADD_RANDOM, zram->disk->queue);
 
 	/*
 	 * To ensure that we always get PAGE_SIZE aligned

drivers/md/bcache/super.c

···
 	}
 
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, d->disk->queue);
-	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, d->disk->queue);
 
 	blk_queue_write_cache(q, true, true);
 

drivers/md/md-bitmap.c

···
 }
 
 static unsigned int bitmap_io_size(unsigned int io_size, unsigned int opt_size,
-				   sector_t start, sector_t boundary)
+				   loff_t start, loff_t boundary)
 {
 	if (io_size != opt_size &&
 	    start + opt_size / SECTOR_SIZE <= boundary)
···
 	struct block_device *bdev;
 	struct mddev *mddev = bitmap->mddev;
 	struct bitmap_storage *store = &bitmap->storage;
-	sector_t offset = mddev->bitmap_info.offset;
-	sector_t ps, sboff, doff;
+	loff_t sboff, offset = mddev->bitmap_info.offset;
+	sector_t ps, doff;
 	unsigned int size = PAGE_SIZE;
 	unsigned int opt_size = PAGE_SIZE;
 

drivers/md/raid5.c

···
 	return ret;
 }
 
+/*
+ * If the bio covers multiple data disks, find sector within the bio that has
+ * the lowest chunk offset in the first chunk.
+ */
+static sector_t raid5_bio_lowest_chunk_sector(struct r5conf *conf,
+					      struct bio *bi)
+{
+	int sectors_per_chunk = conf->chunk_sectors;
+	int raid_disks = conf->raid_disks;
+	int dd_idx;
+	struct stripe_head sh;
+	unsigned int chunk_offset;
+	sector_t r_sector = bi->bi_iter.bi_sector & ~((sector_t)RAID5_STRIPE_SECTORS(conf)-1);
+	sector_t sector;
+
+	/* We pass in fake stripe_head to get back parity disk numbers */
+	sector = raid5_compute_sector(conf, r_sector, 0, &dd_idx, &sh);
+	chunk_offset = sector_div(sector, sectors_per_chunk);
+	if (sectors_per_chunk - chunk_offset >= bio_sectors(bi))
+		return r_sector;
+	/*
+	 * Bio crosses to the next data disk. Check whether it's in the same
+	 * chunk.
+	 */
+	dd_idx++;
+	while (dd_idx == sh.pd_idx || dd_idx == sh.qd_idx)
+		dd_idx++;
+	if (dd_idx >= raid_disks)
+		return r_sector;
+	return r_sector + sectors_per_chunk - chunk_offset;
+}
+
 static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
 {
 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
···
 	}
 	md_account_bio(mddev, &bi);
 
+	/*
+	 * Lets start with the stripe with the lowest chunk offset in the first
+	 * chunk. That has the best chances of creating IOs adjacent to
+	 * previous IOs in case of sequential IO and thus creates the most
+	 * sequential IO pattern. We don't bother with the optimization when
+	 * reshaping as the performance benefit is not worth the complexity.
+	 */
+	if (likely(conf->reshape_progress == MaxSector))
+		logical_sector = raid5_bio_lowest_chunk_sector(conf, bi);
+	s = (logical_sector - ctx.first_sector) >> RAID5_STRIPE_SHIFT(conf);
+
 	add_wait_queue(&conf->wait_for_overlap, &wait);
 	while (1) {
 		res = make_stripe_request(mddev, conf, &ctx, logical_sector,
···
 			continue;
 		}
 
-		s = find_first_bit(ctx.sectors_to_do, stripe_cnt);
+		s = find_next_bit_wrap(ctx.sectors_to_do, stripe_cnt, s);
 		if (s == stripe_cnt)
 			break;
 

fs/fs-writeback.c

···
 		 * is okay.  The main goal is avoiding keeping an inode on
 		 * the wrong wb for an extended period of time.
 		 */
-		if (hweight32(history) > WB_FRN_HIST_THR_SLOTS)
+		if (hweight16(history) > WB_FRN_HIST_THR_SLOTS)
 			inode_switch_wbs(inode, max_id);
 	}
 

include/linux/blkdev.h

···
 	struct timer_rand_state *random;
 	atomic_t sync_io;		/* RAID */
 	struct disk_events *ev;
-#ifdef  CONFIG_BLK_DEV_INTEGRITY
-	struct kobject integrity_kobj;
-#endif	/* CONFIG_BLK_DEV_INTEGRITY */
 
 #ifdef CONFIG_BLK_DEV_ZONED
 	/*

include/uapi/linux/nbd.h

···
  *            Cleanup PARANOIA usage & code.
  * 2004/02/19 Paul Clements
  *            Removed PARANOIA, plus various cleanup and comments
+ * 2023 Copyright Red Hat
+ *            Link to userspace extensions, favor cookie over handle.
  */
 
 #ifndef _UAPILINUX_NBD_H
···
 #define NBD_SET_TIMEOUT _IO( 0xab, 9 )
 #define NBD_SET_FLAGS   _IO( 0xab, 10)
 
+/*
+ * See also https://github.com/NetworkBlockDevice/nbd/blob/master/doc/proto.md
+ * for additional userspace extensions not yet utilized in the kernel module.
+ */
+
 enum {
 	NBD_CMD_READ = 0,
 	NBD_CMD_WRITE = 1,
 	NBD_CMD_DISC = 2,
 	NBD_CMD_FLUSH = 3,
 	NBD_CMD_TRIM = 4
+	/* userspace defines additional extension commands */
 };
 
 /* values for flags field, these are server interaction specific. */
···
 #define NBD_REQUEST_MAGIC 0x25609513
 #define NBD_REPLY_MAGIC 0x67446698
 /* Do *not* use magics: 0x12560953 0x96744668. */
+/* magic 0x668e33ef for structured reply not supported by kernel yet */
 
 /*
  * This is the packet used for communication between client and
  * server. All data are in network byte order.
  */
 struct nbd_request {
-	__be32 magic;
-	__be32 type;	/* == READ || == WRITE 	*/
-	char handle[8];
+	__be32 magic;	/* NBD_REQUEST_MAGIC	*/
+	__be32 type;	/* See NBD_CMD_*	*/
+	union {
+		__be64 cookie;	/* Opaque identifier for request	*/
+		char handle[8];	/* older spelling of cookie		*/
+	};
 	__be64 from;
 	__be32 len;
 } __attribute__((packed));
···
  * it has completed an I/O request (or an error occurs).
  */
 struct nbd_reply {
-	__be32 magic;
+	__be32 magic;		/* NBD_REPLY_MAGIC	*/
 	__be32 error;		/* 0 = ok, else error	*/
-	char handle[8];		/* handle you got from request	*/
+	union {
+		__be64 cookie;	/* Opaque identifier from request	*/
+		char handle[8];	/* older spelling of cookie		*/
+	};
 };
 #endif /* _UAPILINUX_NBD_H */