2 files changed, 144 insertions, 63 deletions

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index f07f5ab31b06..1284cc8cc367 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -40,6 +40,103 @@ static const char *const zone_cond_name[] = {
 #undef ZONE_COND_NAME
 
 /*
+ * Internal and compact representation of enum blk_zone_cond values for zone
+ * conditions. All these values fit into 4-bits, allowing using the high order
+ * bits as the zone type.
+ */
+enum blk_zstate {
+	BLK_ZSTATE_NOT_WP	= 0x00,
+	BLK_ZSTATE_EMPTY	= 0x01,
+	BLK_ZSTATE_IMP_OPEN	= 0x02,
+	BLK_ZSTATE_EXP_OPEN	= 0x03,
+	BLK_ZSTATE_CLOSED	= 0x04,
+	BLK_ZSTATE_READONLY	= 0x05,
+	BLK_ZSTATE_FULL		= 0x06,
+	BLK_ZSTATE_OFFLINE	= 0x07,
+	BLK_ZSTATE_ACTIVE	= 0x08,
+
+	BLK_ZSTATE_COND_MASK	= 0x0F,
+
+	/* Conventional zone. */
+	BLK_ZFLAG_CONV		= 0x80,
+	BLK_ZSTATE_FLAGS_MASK	= ~BLK_ZSTATE_COND_MASK,
+};
+
+/*
+ * Lookup table and helper to convert enum blk_zstate conditions into enum
+ * blk_zone_condition values.
+ */
+static const u8 blk_zstate2zcond[] = {
+	[BLK_ZSTATE_NOT_WP]	= BLK_ZONE_COND_NOT_WP,
+	[BLK_ZSTATE_EMPTY]	= BLK_ZONE_COND_EMPTY,
+	[BLK_ZSTATE_IMP_OPEN]	= BLK_ZONE_COND_IMP_OPEN,
+	[BLK_ZSTATE_EXP_OPEN]	= BLK_ZONE_COND_EXP_OPEN,
+	[BLK_ZSTATE_CLOSED]	= BLK_ZONE_COND_CLOSED,
+	[BLK_ZSTATE_READONLY]	= BLK_ZONE_COND_READONLY,
+	[BLK_ZSTATE_FULL]	= BLK_ZONE_COND_FULL,
+	[BLK_ZSTATE_OFFLINE]	= BLK_ZONE_COND_OFFLINE,
+	[BLK_ZSTATE_ACTIVE]	= BLK_ZONE_COND_ACTIVE,
+};
+
+static inline enum blk_zone_cond blk_zstate_to_zone_cond(enum blk_zstate zs)
+{
+	u8 idx = zs & BLK_ZSTATE_COND_MASK;
+
+	if (WARN_ON_ONCE(idx >= ARRAY_SIZE(blk_zstate2zcond)))
+		return 0;
+
+	return blk_zstate2zcond[idx];
+}
+
+/*
+ * Lookup table and helper to convert an enum blk_zone_condition into an enum
+ * blk_zstate condition value. To keep the lookup table small, the
+ * BLK_ZONE_COND_ACTIVE condition is not added and handled separately.
+ */
+static const u8 blk_zcond2zstate[] = {
+	[BLK_ZONE_COND_NOT_WP]		= BLK_ZSTATE_NOT_WP,
+	[BLK_ZONE_COND_EMPTY]		= BLK_ZSTATE_EMPTY,
+	[BLK_ZONE_COND_IMP_OPEN]	= BLK_ZSTATE_ACTIVE,
+	[BLK_ZONE_COND_EXP_OPEN]	= BLK_ZSTATE_ACTIVE,
+	[BLK_ZONE_COND_CLOSED]		= BLK_ZSTATE_ACTIVE,
+	[BLK_ZONE_COND_READONLY]	= BLK_ZSTATE_READONLY,
+	[BLK_ZONE_COND_FULL]		= BLK_ZSTATE_FULL,
+	[BLK_ZONE_COND_OFFLINE]		= BLK_ZSTATE_OFFLINE,
+};
+
+static inline enum blk_zstate blk_zone_cond_to_zstate(enum blk_zone_cond cond)
+{
+	if (cond == BLK_ZONE_COND_ACTIVE)
+		return BLK_ZSTATE_ACTIVE;
+
+	if (WARN_ON_ONCE(cond >= ARRAY_SIZE(blk_zcond2zstate)))
+		return 0;
+
+	return blk_zcond2zstate[cond];
+}
+
+/*
+ * Combine an enum blk_zone_condition and zone flags into a zones_state array
+ * entry.
+ */
+static inline void blk_zstate_set(u8 *zones_state, unsigned int nr_zones,
+			unsigned int zno, enum blk_zone_cond cond, u8 flags)
+{
+	if (zones_state && zno < nr_zones)
+		zones_state[zno] = flags | blk_zone_cond_to_zstate(cond);
+}
+
+static inline u8 blk_zstate_flags(enum blk_zstate zs)
+{
+	return zs & BLK_ZSTATE_FLAGS_MASK;
+}
+
+static inline bool blk_zstate_is_conv(enum blk_zstate zs)
+{
+	return blk_zstate_flags(zs) & BLK_ZFLAG_CONV;
+}
+
+/*
  * Per-zone write plug.
  * @node: hlist_node structure for managing the plug using a hash table.
  * @entry: list_head structure for listing the plug in the disk list of active
@@ -135,51 +232,28 @@ const char *blk_zone_cond_str(enum blk_zone_cond zone_cond)
 }
 EXPORT_SYMBOL_GPL(blk_zone_cond_str);
 
-static void blk_zone_set_cond(u8 *zones_cond, unsigned int zno,
-			      enum blk_zone_cond cond)
-{
-	if (!zones_cond)
-		return;
-
-	switch (cond) {
-	case BLK_ZONE_COND_IMP_OPEN:
-	case BLK_ZONE_COND_EXP_OPEN:
-	case BLK_ZONE_COND_CLOSED:
-		zones_cond[zno] = BLK_ZONE_COND_ACTIVE;
-		return;
-	case BLK_ZONE_COND_NOT_WP:
-	case BLK_ZONE_COND_EMPTY:
-	case BLK_ZONE_COND_FULL:
-	case BLK_ZONE_COND_OFFLINE:
-	case BLK_ZONE_COND_READONLY:
-	default:
-		zones_cond[zno] = cond;
-		return;
-	}
-}
-
 static void disk_zone_set_cond(struct gendisk *disk, sector_t sector,
 			       enum blk_zone_cond cond)
 {
-	u8 *zones_cond;
+	unsigned int zno = disk_zone_no(disk, sector);
+	u8 *zones_state;
 
 	rcu_read_lock();
-	zones_cond = rcu_dereference(disk->zones_cond);
-	if (zones_cond) {
-		unsigned int zno = disk_zone_no(disk, sector);
-
+	zones_state = rcu_dereference(disk->zones_state);
+	if (zones_state && zno < disk->nr_zones) {
 		/*
 		 * The condition of a conventional, readonly and offline zones
 		 * never changes, so do nothing if the target zone is in one of
 		 * these conditions.
 		 */
-		switch (zones_cond[zno]) {
-		case BLK_ZONE_COND_NOT_WP:
-		case BLK_ZONE_COND_READONLY:
-		case BLK_ZONE_COND_OFFLINE:
+		switch (zones_state[zno] & BLK_ZSTATE_COND_MASK) {
+		case BLK_ZSTATE_NOT_WP:
+		case BLK_ZSTATE_READONLY:
+		case BLK_ZSTATE_OFFLINE:
 			break;
 		default:
-			blk_zone_set_cond(zones_cond, zno, cond);
+			blk_zstate_set(zones_state, disk->nr_zones, zno, cond,
+				       blk_zstate_flags(zones_state[zno]));
 			break;
 		}
 	}
@@ -198,15 +272,15 @@ bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector)
 	struct gendisk *disk = bdev->bd_disk;
 	unsigned int zno = disk_zone_no(disk, sector);
 	bool is_seq = false;
-	u8 *zones_cond;
+	u8 *zones_state;
 
 	if (!bdev_is_zoned(bdev))
 		return false;
 
 	rcu_read_lock();
-	zones_cond = rcu_dereference(disk->zones_cond);
-	if (zones_cond && zno < disk->nr_zones)
-		is_seq = zones_cond[zno] != BLK_ZONE_COND_NOT_WP;
+	zones_state = rcu_dereference(disk->zones_state);
+	if (zones_state && zno < disk->nr_zones)
+		is_seq = !blk_zstate_is_conv(zones_state[zno]);
 	rcu_read_unlock();
 
 	return is_seq;
@@ -505,7 +579,7 @@ static bool disk_insert_zone_wplug(struct gendisk *disk,
 {
 	struct blk_zone_wplug *zwplg;
 	unsigned long flags;
-	u8 *zones_cond;
+	u8 *zones_state;
 	unsigned int idx =
 		hash_32(zwplug->zone_no, disk->zone_wplugs_hash_bits);
 
@@ -524,15 +598,16 @@ static bool disk_insert_zone_wplug(struct gendisk *disk,
 	}
 
 	/*
-	 * Set the zone condition: if we do not yet have a zones_cond array
+	 * Set the zone condition: if we do not yet have a zones_state array
 	 * attached to the disk, then this is a zone write plug insert from the
 	 * first call to blk_revalidate_disk_zones(), in which case the zone is
 	 * necessarilly in the active condition.
 	 */
-	zones_cond = rcu_dereference_check(disk->zones_cond,
+	zones_state = rcu_dereference_check(disk->zones_state,
 				lockdep_is_held(&disk->zone_wplugs_hash_lock));
-	if (zones_cond)
-		zwplug->cond = zones_cond[zwplug->zone_no];
+	if (zones_state)
+		zwplug->cond =
+			blk_zstate_to_zone_cond(zones_state[zwplug->zone_no]);
 	else
 		zwplug->cond = BLK_ZONE_COND_ACTIVE;
 
@@ -592,9 +667,9 @@ static void disk_free_zone_wplug(struct blk_zone_wplug *zwplug)
 	WARN_ON_ONCE(!bio_list_empty(&zwplug->bio_list));
 
 	spin_lock_irqsave(&disk->zone_wplugs_hash_lock, flags);
-	blk_zone_set_cond(rcu_dereference_check(disk->zones_cond,
+	blk_zstate_set(rcu_dereference_check(disk->zones_state,
 				lockdep_is_held(&disk->zone_wplugs_hash_lock)),
-			  zwplug->zone_no, zwplug->cond);
+		       disk->nr_zones, zwplug->zone_no, zwplug->cond, 0);
 	hlist_del_init_rcu(&zwplug->node);
 	atomic_dec(&disk->nr_zone_wplugs);
 	spin_unlock_irqrestore(&disk->zone_wplugs_hash_lock, flags);
@@ -940,7 +1015,7 @@ int blkdev_get_zone_info(struct block_device *bdev, sector_t sector,
 	sector_t zone_sectors = bdev_zone_sectors(bdev);
 	struct blk_zone_wplug *zwplug;
 	unsigned long flags;
-	u8 *zones_cond;
+	u8 *zones_state, zs;
 
 	if (!bdev_is_zoned(bdev))
 		return -EOPNOTSUPP;
@@ -955,12 +1030,18 @@ int blkdev_get_zone_info(struct block_device *bdev, sector_t sector,
 		return blkdev_report_zone_fallback(bdev, sector, zone);
 
 	rcu_read_lock();
-	zones_cond = rcu_dereference(disk->zones_cond);
-	if (!disk->zone_wplugs_hash || !zones_cond) {
+	zones_state = rcu_dereference(disk->zones_state);
+	if (!disk->zone_wplugs_hash || !zones_state) {
 		rcu_read_unlock();
 		return blkdev_report_zone_fallback(bdev, sector, zone);
 	}
-	zone->cond = zones_cond[disk_zone_no(disk, sector)];
+
+	zs = zones_state[disk_zone_no(disk, sector)];
+	zone->cond = blk_zstate_to_zone_cond(zs);
+	if (blk_zstate_is_conv(zs))
+		zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
+	else
+		zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
 	rcu_read_unlock();
 
 	zone->start = sector;
@@ -970,8 +1051,7 @@ int blkdev_get_zone_info(struct block_device *bdev, sector_t sector,
 	 * If this is a conventional zone, we do not have a zone write plug and
 	 * can report the zone immediately.
 	 */
-	if (zone->cond == BLK_ZONE_COND_NOT_WP) {
-		zone->type = BLK_ZONE_TYPE_CONVENTIONAL;
+	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
 		zone->capacity = zone_sectors;
 		zone->wp = ULLONG_MAX;
 		return 0;
@@ -982,7 +1062,6 @@ int blkdev_get_zone_info(struct block_device *bdev, sector_t sector,
 	 * offline, only set the zone write pointer to an invalid value and
 	 * report the zone.
 	 */
-	zone->type = BLK_ZONE_TYPE_SEQWRITE_REQ;
 	if (disk_zone_is_last(disk, zone))
 		zone->capacity = disk->last_zone_capacity;
 	else
@@ -1980,16 +2059,16 @@ static void disk_destroy_zone_wplugs_hash_table(struct gendisk *disk)
 	disk->zone_wplugs_pool = NULL;
 }
 
-static void disk_set_zones_cond_array(struct gendisk *disk, u8 *zones_cond)
+static void disk_set_zones_state_array(struct gendisk *disk, u8 *zones_state)
 {
 	unsigned long flags;
 
 	spin_lock_irqsave(&disk->zone_wplugs_hash_lock, flags);
-	zones_cond = rcu_replace_pointer(disk->zones_cond, zones_cond,
+	zones_state = rcu_replace_pointer(disk->zones_state, zones_state,
 				lockdep_is_held(&disk->zone_wplugs_hash_lock));
 	spin_unlock_irqrestore(&disk->zone_wplugs_hash_lock, flags);
 
-	kfree_rcu_mightsleep(zones_cond);
+	kfree_rcu_mightsleep(zones_state);
 }
 
 void disk_release_zone_resources(struct gendisk *disk)
@@ -2007,7 +2086,7 @@ void disk_release_zone_resources(struct gendisk *disk)
 
 	disk_destroy_zone_wplugs_hash_table(disk);
 
-	disk_set_zones_cond_array(disk, NULL);
+	disk_set_zones_state_array(disk, NULL);
 	disk->zone_capacity = 0;
 	disk->last_zone_capacity = 0;
 	disk->nr_zones = 0;
@@ -2016,7 +2095,7 @@ void disk_release_zone_resources(struct gendisk *disk)
 struct blk_revalidate_zone_args {
 	struct gendisk	*disk;
 	sector_t	capacity;
-	u8		*zones_cond;
+	u8		*zones_state;
 	unsigned int	nr_zones;
 	unsigned int	nr_conv_zones;
 	unsigned int	zone_capacity;
@@ -2031,8 +2110,8 @@ static int disk_init_revalidate_args(struct gendisk *disk,
 	args->nr_zones = disk_get_nr_zones(disk, args->capacity);
 
 	/* Cached zone conditions: 1 byte per zone */
-	args->zones_cond = kzalloc(args->nr_zones, GFP_NOIO);
-	if (!args->zones_cond)
+	args->zones_state = kzalloc(args->nr_zones, GFP_NOIO);
+	if (!args->zones_state)
 		return -ENOMEM;
 
 	return 0;
@@ -2086,8 +2165,8 @@ static int disk_revalidate_zone_resources(struct gendisk *disk,
 	disk->nr_zones = args->nr_zones;
 	disk->zone_capacity = args->zone_capacity;
 	disk->last_zone_capacity = args->last_zone_capacity;
-	disk_set_zones_cond_array(disk, args->zones_cond);
-	args->zones_cond = NULL;
+	disk_set_zones_state_array(disk, args->zones_state);
+	args->zones_state = NULL;
 
 	/*
 	 * Some devices can advertise zone resource limits that are larger than
@@ -2139,12 +2218,14 @@ static int blk_revalidate_zone_cond(struct blk_zone *zone, unsigned int idx,
 				    struct blk_revalidate_zone_args *args)
 {
 	enum blk_zone_cond cond = zone->cond;
+	u8 flags = 0;
 
 	/* Check that the zone condition is consistent with the zone type. */
 	switch (cond) {
 	case BLK_ZONE_COND_NOT_WP:
 		if (zone->type != BLK_ZONE_TYPE_CONVENTIONAL)
 			goto invalid_condition;
+		flags = BLK_ZFLAG_CONV;
 		break;
 	case BLK_ZONE_COND_IMP_OPEN:
 	case BLK_ZONE_COND_EXP_OPEN:
@@ -2162,7 +2243,7 @@ static int blk_revalidate_zone_cond(struct blk_zone *zone, unsigned int idx,
 		return -ENODEV;
 	}
 
-	blk_zone_set_cond(args->zones_cond, idx, cond);
+	blk_zstate_set(args->zones_state, args->nr_zones, idx, cond, flags);
 
 	return 0;
 
@@ -2390,7 +2471,7 @@ int blk_revalidate_disk_zones(struct gendisk *disk)
 free_args:
 	pr_warn("%s: failed to revalidate zones\n", disk->disk_name);
 
-	kfree(args.zones_cond);
+	kfree(args.zones_state);
 
 	return ret;
 }
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 098a65f3e48b..b91511bfbfbd 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -198,7 +198,7 @@ struct gendisk {
 	unsigned int		nr_zones;
 	unsigned int		zone_capacity;
 	unsigned int		last_zone_capacity;
-	u8 __rcu		*zones_cond;
+	u8 __rcu		*zones_state;
 	unsigned int		zone_wplugs_hash_bits;
 	atomic_t		nr_zone_wplugs;
 	spinlock_t		zone_wplugs_hash_lock;