1 files changed, 84 insertions, 417 deletions

diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
index eb9832b22b14..8e6bcb0d786a 100644
--- a/drivers/md/dm-zone.c
+++ b/drivers/md/dm-zone.c
@@ -60,16 +60,23 @@ int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
 	struct dm_table *map;
 	int srcu_idx, ret;
 
-	if (dm_suspended_md(md))
-		return -EAGAIN;
+	if (!md->zone_revalidate_map) {
+		/* Regular user context */
+		if (dm_suspended_md(md))
+			return -EAGAIN;
 
-	map = dm_get_live_table(md, &srcu_idx);
-	if (!map)
-		return -EIO;
+		map = dm_get_live_table(md, &srcu_idx);
+		if (!map)
+			return -EIO;
+	} else {
+		/* Zone revalidation during __bind() */
+		map = md->zone_revalidate_map;
+	}
 
 	ret = dm_blk_do_report_zones(md, map, sector, nr_zones, cb, data);
 
-	dm_put_live_table(md, srcu_idx);
+	if (!md->zone_revalidate_map)
+		dm_put_live_table(md, srcu_idx);
 
 	return ret;
 }
@@ -138,80 +145,47 @@ bool dm_is_zone_write(struct mapped_device *md, struct bio *bio)
 	}
 }
 
-void dm_cleanup_zoned_dev(struct mapped_device *md)
+/*
+ * Count conventional zones of a mapped zoned device. If the device
+ * only has conventional zones, do not expose it as zoned.
+ */
+static int dm_check_zoned_cb(struct blk_zone *zone, unsigned int idx,
+			     void *data)
 {
-	if (md->disk) {
-		bitmap_free(md->disk->conv_zones_bitmap);
-		md->disk->conv_zones_bitmap = NULL;
-		bitmap_free(md->disk->seq_zones_wlock);
-		md->disk->seq_zones_wlock = NULL;
-	}
+	unsigned int *nr_conv_zones = data;
 
-	kvfree(md->zwp_offset);
-	md->zwp_offset = NULL;
-	md->nr_zones = 0;
-}
+	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
+		(*nr_conv_zones)++;
 
-static unsigned int dm_get_zone_wp_offset(struct blk_zone *zone)
-{
-	switch (zone->cond) {
-	case BLK_ZONE_COND_IMP_OPEN:
-	case BLK_ZONE_COND_EXP_OPEN:
-	case BLK_ZONE_COND_CLOSED:
-		return zone->wp - zone->start;
-	case BLK_ZONE_COND_FULL:
-		return zone->len;
-	case BLK_ZONE_COND_EMPTY:
-	case BLK_ZONE_COND_NOT_WP:
-	case BLK_ZONE_COND_OFFLINE:
-	case BLK_ZONE_COND_READONLY:
-	default:
-		/*
-		 * Conventional, offline and read-only zones do not have a valid
-		 * write pointer. Use 0 as for an empty zone.
-		 */
-		return 0;
-	}
+	return 0;
 }
 
-static int dm_zone_revalidate_cb(struct blk_zone *zone, unsigned int idx,
-				 void *data)
+static int dm_check_zoned(struct mapped_device *md, struct dm_table *t)
 {
-	struct mapped_device *md = data;
 	struct gendisk *disk = md->disk;
+	unsigned int nr_conv_zones = 0;
+	int ret;
 
-	switch (zone->type) {
-	case BLK_ZONE_TYPE_CONVENTIONAL:
-		if (!disk->conv_zones_bitmap) {
-			disk->conv_zones_bitmap = bitmap_zalloc(disk->nr_zones,
-								GFP_NOIO);
-			if (!disk->conv_zones_bitmap)
-				return -ENOMEM;
-		}
-		set_bit(idx, disk->conv_zones_bitmap);
-		break;
-	case BLK_ZONE_TYPE_SEQWRITE_REQ:
-	case BLK_ZONE_TYPE_SEQWRITE_PREF:
-		if (!disk->seq_zones_wlock) {
-			disk->seq_zones_wlock = bitmap_zalloc(disk->nr_zones,
-							      GFP_NOIO);
-			if (!disk->seq_zones_wlock)
-				return -ENOMEM;
-		}
-		if (!md->zwp_offset) {
-			md->zwp_offset =
-				kvcalloc(disk->nr_zones, sizeof(unsigned int),
-					 GFP_KERNEL);
-			if (!md->zwp_offset)
-				return -ENOMEM;
-		}
-		md->zwp_offset[idx] = dm_get_zone_wp_offset(zone);
-
-		break;
-	default:
-		DMERR("Invalid zone type 0x%x at sectors %llu",
-		      (int)zone->type, zone->start);
-		return -ENODEV;
+	/* Count conventional zones */
+	md->zone_revalidate_map = t;
+	ret = dm_blk_report_zones(disk, 0, UINT_MAX,
+				  dm_check_zoned_cb, &nr_conv_zones);
+	md->zone_revalidate_map = NULL;
+	if (ret < 0) {
+		DMERR("Check zoned failed %d", ret);
+		return ret;
+	}
+
+	/*
+	 * If we only have conventional zones, expose the mapped device as
+	 * a regular device.
+	 */
+	if (nr_conv_zones >= ret) {
+		disk->queue->limits.max_open_zones = 0;
+		disk->queue->limits.max_active_zones = 0;
+		disk->queue->limits.zoned = false;
+		clear_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
+		disk->nr_zones = 0;
 	}
 
 	return 0;
@@ -226,41 +200,32 @@ static int dm_zone_revalidate_cb(struct blk_zone *zone, unsigned int idx,
 static int dm_revalidate_zones(struct mapped_device *md, struct dm_table *t)
 {
 	struct gendisk *disk = md->disk;
-	unsigned int noio_flag;
 	int ret;
 
-	/*
-	 * Check if something changed. If yes, cleanup the current resources
-	 * and reallocate everything.
-	 */
+	/* Revalidate only if something changed. */
 	if (!disk->nr_zones || disk->nr_zones != md->nr_zones)
-		dm_cleanup_zoned_dev(md);
+		md->nr_zones = 0;
+
 	if (md->nr_zones)
 		return 0;
 
 	/*
-	 * Scan all zones to initialize everything. Ensure that all vmalloc
-	 * operations in this context are done as if GFP_NOIO was specified.
+	 * Our table is not live yet. So the call to dm_get_live_table()
+	 * in dm_blk_report_zones() will fail. Set a temporary pointer to
+	 * our table for dm_blk_report_zones() to use directly.
 	 */
-	noio_flag = memalloc_noio_save();
-	ret = dm_blk_do_report_zones(md, t, 0, disk->nr_zones,
-				     dm_zone_revalidate_cb, md);
-	memalloc_noio_restore(noio_flag);
-	if (ret < 0)
-		goto err;
-	if (ret != disk->nr_zones) {
-		ret = -EIO;
-		goto err;
+	md->zone_revalidate_map = t;
+	ret = blk_revalidate_disk_zones(disk);
+	md->zone_revalidate_map = NULL;
+
+	if (ret) {
+		DMERR("Revalidate zones failed %d", ret);
+		return ret;
 	}
 
 	md->nr_zones = disk->nr_zones;
 
 	return 0;
-
-err:
-	DMERR("Revalidate zones failed %d", ret);
-	dm_cleanup_zoned_dev(md);
-	return ret;
 }
 
 static int device_not_zone_append_capable(struct dm_target *ti,
@@ -289,294 +254,40 @@ static bool dm_table_supports_zone_append(struct dm_table *t)
 int dm_set_zones_restrictions(struct dm_table *t, struct request_queue *q)
 {
 	struct mapped_device *md = t->md;
+	int ret;
 
 	/*
-	 * For a zoned target, the number of zones should be updated for the
-	 * correct value to be exposed in sysfs queue/nr_zones.
+	 * Check if zone append is natively supported, and if not, set the
+	 * mapped device queue as needing zone append emulation.
 	 */
 	WARN_ON_ONCE(queue_is_mq(q));
-	md->disk->nr_zones = bdev_nr_zones(md->disk->part0);
-
-	/* Check if zone append is natively supported */
 	if (dm_table_supports_zone_append(t)) {
 		clear_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
-		dm_cleanup_zoned_dev(md);
-		return 0;
+	} else {
+		set_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
+		blk_queue_max_zone_append_sectors(q, 0);
 	}
 
-	/*
-	 * Mark the mapped device as needing zone append emulation and
-	 * initialize the emulation resources once the capacity is set.
-	 */
-	set_bit(DMF_EMULATE_ZONE_APPEND, &md->flags);
 	if (!get_capacity(md->disk))
 		return 0;
 
-	return dm_revalidate_zones(md, t);
-}
-
-static int dm_update_zone_wp_offset_cb(struct blk_zone *zone, unsigned int idx,
-				       void *data)
-{
-	unsigned int *wp_offset = data;
-
-	*wp_offset = dm_get_zone_wp_offset(zone);
-
-	return 0;
-}
-
-static int dm_update_zone_wp_offset(struct mapped_device *md, unsigned int zno,
-				    unsigned int *wp_ofst)
-{
-	sector_t sector = zno * bdev_zone_sectors(md->disk->part0);
-	unsigned int noio_flag;
-	struct dm_table *t;
-	int srcu_idx, ret;
-
-	t = dm_get_live_table(md, &srcu_idx);
-	if (!t)
-		return -EIO;
-
-	/*
-	 * Ensure that all memory allocations in this context are done as if
-	 * GFP_NOIO was specified.
-	 */
-	noio_flag = memalloc_noio_save();
-	ret = dm_blk_do_report_zones(md, t, sector, 1,
-				     dm_update_zone_wp_offset_cb, wp_ofst);
-	memalloc_noio_restore(noio_flag);
-
-	dm_put_live_table(md, srcu_idx);
-
-	if (ret != 1)
-		return -EIO;
-
-	return 0;
-}
-
-struct orig_bio_details {
-	enum req_op op;
-	unsigned int nr_sectors;
-};
-
-/*
- * First phase of BIO mapping for targets with zone append emulation:
- * check all BIO that change a zone writer pointer and change zone
- * append operations into regular write operations.
- */
-static bool dm_zone_map_bio_begin(struct mapped_device *md,
-				  unsigned int zno, struct bio *clone)
-{
-	sector_t zsectors = bdev_zone_sectors(md->disk->part0);
-	unsigned int zwp_offset = READ_ONCE(md->zwp_offset[zno]);
-
-	/*
-	 * If the target zone is in an error state, recover by inspecting the
-	 * zone to get its current write pointer position. Note that since the
-	 * target zone is already locked, a BIO issuing context should never
-	 * see the zone write in the DM_ZONE_UPDATING_WP_OFST state.
-	 */
-	if (zwp_offset == DM_ZONE_INVALID_WP_OFST) {
-		if (dm_update_zone_wp_offset(md, zno, &zwp_offset))
-			return false;
-		WRITE_ONCE(md->zwp_offset[zno], zwp_offset);
-	}
-
-	switch (bio_op(clone)) {
-	case REQ_OP_ZONE_RESET:
-	case REQ_OP_ZONE_FINISH:
-		return true;
-	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE:
-		/* Writes must be aligned to the zone write pointer */
-		if ((clone->bi_iter.bi_sector & (zsectors - 1)) != zwp_offset)
-			return false;
-		break;
-	case REQ_OP_ZONE_APPEND:
-		/*
-		 * Change zone append operations into a non-mergeable regular
-		 * writes directed at the current write pointer position of the
-		 * target zone.
-		 */
-		clone->bi_opf = REQ_OP_WRITE | REQ_NOMERGE |
-			(clone->bi_opf & (~REQ_OP_MASK));
-		clone->bi_iter.bi_sector += zwp_offset;
-		break;
-	default:
-		DMWARN_LIMIT("Invalid BIO operation");
-		return false;
-	}
-
-	/* Cannot write to a full zone */
-	if (zwp_offset >= zsectors)
-		return false;
-
-	return true;
-}
-
-/*
- * Second phase of BIO mapping for targets with zone append emulation:
- * update the zone write pointer offset array to account for the additional
- * data written to a zone. Note that at this point, the remapped clone BIO
- * may already have completed, so we do not touch it.
- */
-static blk_status_t dm_zone_map_bio_end(struct mapped_device *md, unsigned int zno,
-					struct orig_bio_details *orig_bio_details,
-					unsigned int nr_sectors)
-{
-	unsigned int zwp_offset = READ_ONCE(md->zwp_offset[zno]);
-
-	/* The clone BIO may already have been completed and failed */
-	if (zwp_offset == DM_ZONE_INVALID_WP_OFST)
-		return BLK_STS_IOERR;
-
-	/* Update the zone wp offset */
-	switch (orig_bio_details->op) {
-	case REQ_OP_ZONE_RESET:
-		WRITE_ONCE(md->zwp_offset[zno], 0);
-		return BLK_STS_OK;
-	case REQ_OP_ZONE_FINISH:
-		WRITE_ONCE(md->zwp_offset[zno],
-			   bdev_zone_sectors(md->disk->part0));
-		return BLK_STS_OK;
-	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE:
-		WRITE_ONCE(md->zwp_offset[zno], zwp_offset + nr_sectors);
-		return BLK_STS_OK;
-	case REQ_OP_ZONE_APPEND:
-		/*
-		 * Check that the target did not truncate the write operation
-		 * emulating a zone append.
-		 */
-		if (nr_sectors != orig_bio_details->nr_sectors) {
-			DMWARN_LIMIT("Truncated write for zone append");
-			return BLK_STS_IOERR;
-		}
-		WRITE_ONCE(md->zwp_offset[zno], zwp_offset + nr_sectors);
-		return BLK_STS_OK;
-	default:
-		DMWARN_LIMIT("Invalid BIO operation");
-		return BLK_STS_IOERR;
-	}
-}
-
-static inline void dm_zone_lock(struct gendisk *disk, unsigned int zno,
-				struct bio *clone)
-{
-	if (WARN_ON_ONCE(bio_flagged(clone, BIO_ZONE_WRITE_LOCKED)))
-		return;
-
-	wait_on_bit_lock_io(disk->seq_zones_wlock, zno, TASK_UNINTERRUPTIBLE);
-	bio_set_flag(clone, BIO_ZONE_WRITE_LOCKED);
-}
-
-static inline void dm_zone_unlock(struct gendisk *disk, unsigned int zno,
-				  struct bio *clone)
-{
-	if (!bio_flagged(clone, BIO_ZONE_WRITE_LOCKED))
-		return;
-
-	WARN_ON_ONCE(!test_bit(zno, disk->seq_zones_wlock));
-	clear_bit_unlock(zno, disk->seq_zones_wlock);
-	smp_mb__after_atomic();
-	wake_up_bit(disk->seq_zones_wlock, zno);
-
-	bio_clear_flag(clone, BIO_ZONE_WRITE_LOCKED);
-}
-
-static bool dm_need_zone_wp_tracking(struct bio *bio)
-{
 	/*
-	 * Special processing is not needed for operations that do not need the
-	 * zone write lock, that is, all operations that target conventional
-	 * zones and all operations that do not modify directly a sequential
-	 * zone write pointer.
+	 * Check that the mapped device will indeed be zoned, that is, that it
+	 * has sequential write required zones.
 	 */
-	if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
-		return false;
-	switch (bio_op(bio)) {
-	case REQ_OP_WRITE_ZEROES:
-	case REQ_OP_WRITE:
-	case REQ_OP_ZONE_RESET:
-	case REQ_OP_ZONE_FINISH:
-	case REQ_OP_ZONE_APPEND:
-		return bio_zone_is_seq(bio);
-	default:
-		return false;
-	}
-}
-
-/*
- * Special IO mapping for targets needing zone append emulation.
- */
-int dm_zone_map_bio(struct dm_target_io *tio)
-{
-	struct dm_io *io = tio->io;
-	struct dm_target *ti = tio->ti;
-	struct mapped_device *md = io->md;
-	struct bio *clone = &tio->clone;
-	struct orig_bio_details orig_bio_details;
-	unsigned int zno;
-	blk_status_t sts;
-	int r;
-
-	/*
-	 * IOs that do not change a zone write pointer do not need
-	 * any additional special processing.
-	 */
-	if (!dm_need_zone_wp_tracking(clone))
-		return ti->type->map(ti, clone);
-
-	/* Lock the target zone */
-	zno = bio_zone_no(clone);
-	dm_zone_lock(md->disk, zno, clone);
-
-	orig_bio_details.nr_sectors = bio_sectors(clone);
-	orig_bio_details.op = bio_op(clone);
+	ret = dm_check_zoned(md, t);
+	if (ret)
+		return ret;
+	if (!blk_queue_is_zoned(q))
+		return 0;
 
-	/*
-	 * Check that the bio and the target zone write pointer offset are
-	 * both valid, and if the bio is a zone append, remap it to a write.
-	 */
-	if (!dm_zone_map_bio_begin(md, zno, clone)) {
-		dm_zone_unlock(md->disk, zno, clone);
-		return DM_MAPIO_KILL;
+	if (!md->disk->nr_zones) {
+		DMINFO("%s using %s zone append",
+		       md->disk->disk_name,
+		       queue_emulates_zone_append(q) ? "emulated" : "native");
 	}
 
-	/* Let the target do its work */
-	r = ti->type->map(ti, clone);
-	switch (r) {
-	case DM_MAPIO_SUBMITTED:
-		/*
-		 * The target submitted the clone BIO. The target zone will
-		 * be unlocked on completion of the clone.
-		 */
-		sts = dm_zone_map_bio_end(md, zno, &orig_bio_details,
-					  *tio->len_ptr);
-		break;
-	case DM_MAPIO_REMAPPED:
-		/*
-		 * The target only remapped the clone BIO. In case of error,
-		 * unlock the target zone here as the clone will not be
-		 * submitted.
-		 */
-		sts = dm_zone_map_bio_end(md, zno, &orig_bio_details,
-					  *tio->len_ptr);
-		if (sts != BLK_STS_OK)
-			dm_zone_unlock(md->disk, zno, clone);
-		break;
-	case DM_MAPIO_REQUEUE:
-	case DM_MAPIO_KILL:
-	default:
-		dm_zone_unlock(md->disk, zno, clone);
-		sts = BLK_STS_IOERR;
-		break;
-	}
-
-	if (sts != BLK_STS_OK)
-		return DM_MAPIO_KILL;
-
-	return r;
+	return dm_revalidate_zones(md, t);
 }
 
 /*
@@ -587,61 +298,17 @@ void dm_zone_endio(struct dm_io *io, struct bio *clone)
 	struct mapped_device *md = io->md;
 	struct gendisk *disk = md->disk;
 	struct bio *orig_bio = io->orig_bio;
-	unsigned int zwp_offset;
-	unsigned int zno;
 
 	/*
-	 * For targets that do not emulate zone append, we only need to
-	 * handle native zone-append bios.
+	 * Get the offset within the zone of the written sector
+	 * and add that to the original bio sector position.
 	 */
-	if (!dm_emulate_zone_append(md)) {
-		/*
-		 * Get the offset within the zone of the written sector
-		 * and add that to the original bio sector position.
-		 */
-		if (clone->bi_status == BLK_STS_OK &&
-		    bio_op(clone) == REQ_OP_ZONE_APPEND) {
-			sector_t mask =
-				(sector_t)bdev_zone_sectors(disk->part0) - 1;
-
-			orig_bio->bi_iter.bi_sector +=
-				clone->bi_iter.bi_sector & mask;
-		}
-
-		return;
-	}
+	if (clone->bi_status == BLK_STS_OK &&
+	    bio_op(clone) == REQ_OP_ZONE_APPEND) {
+		sector_t mask = bdev_zone_sectors(disk->part0) - 1;
 
-	/*
-	 * For targets that do emulate zone append, if the clone BIO does not
-	 * own the target zone write lock, we have nothing to do.
-	 */
-	if (!bio_flagged(clone, BIO_ZONE_WRITE_LOCKED))
-		return;
-
-	zno = bio_zone_no(orig_bio);
-
-	if (clone->bi_status != BLK_STS_OK) {
-		/*
-		 * BIOs that modify a zone write pointer may leave the zone
-		 * in an unknown state in case of failure (e.g. the write
-		 * pointer was only partially advanced). In this case, set
-		 * the target zone write pointer as invalid unless it is
-		 * already being updated.
-		 */
-		WRITE_ONCE(md->zwp_offset[zno], DM_ZONE_INVALID_WP_OFST);
-	} else if (bio_op(orig_bio) == REQ_OP_ZONE_APPEND) {
-		/*
-		 * Get the written sector for zone append operation that were
-		 * emulated using regular write operations.
-		 */
-		zwp_offset = READ_ONCE(md->zwp_offset[zno]);
-		if (WARN_ON_ONCE(zwp_offset < bio_sectors(orig_bio)))
-			WRITE_ONCE(md->zwp_offset[zno],
-				   DM_ZONE_INVALID_WP_OFST);
-		else
-			orig_bio->bi_iter.bi_sector +=
-				zwp_offset - bio_sectors(orig_bio);
+		orig_bio->bi_iter.bi_sector += clone->bi_iter.bi_sector & mask;
 	}
 
-	dm_zone_unlock(disk, zno, clone);
+	return;
 }