Merge branch 'cached-zones' into for-6.19/block

This patch series implements a cached report zones using information
from the block layer zone write plugs and a new zone condition tracking.
This avoids having to execute slow report zones commands on the device
when for instance mounting file systems, which can significantly speed
things up, especially in setups with multiple SMR HDDs (e.g. a BTRFS
RAID volume).

The first patch improves handling of zone management commands. Patch 2
fixes zone resource updates and the following 3 patches cleanup the zone
code in preparation for introducing cached zone report support.
From patch 6 to 13, cached report zones is implemented and made
available to users with a new ioctl() command.

Finally, patches 14 and 15 introduce the use of cached report zones in
the mount operation of XFS and BTRFS.

Link: https://lore.kernel.org/linux-block/20251104212249.1075412-1-dlemoal@kernel.org/
Signed-off-by: Jens Axboe <axboe@kernel.dk>

* cached-zones:
  xfs: use blkdev_report_zones_cached()
  btrfs: use blkdev_report_zones_cached()
  block: add zone write plug condition to debugfs zone_wplugs
  block: improve zone_wplugs debugfs attribute output
  block: introduce BLKREPORTZONESV2 ioctl
  block: introduce blkdev_report_zones_cached()
  block: introduce blkdev_get_zone_info()
  block: refactor blkdev_report_zones() code
  block: track zone conditions
  block: use zone condition to determine conventional zones
  block: reorganize struct blk_zone_wplug
  block: introduce disk_report_zone()
  block: cleanup blkdev_report_zones()
  block: freeze queue when updating zone resources
  block: handle zone management operations completions

1 files changed, 20 insertions, 29 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 99be263b31ab..f0ab02e0a673 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -38,6 +38,7 @@ struct blk_flush_queue;
 struct kiocb;
 struct pr_ops;
 struct rq_qos;
+struct blk_report_zones_args;
 struct blk_queue_stats;
 struct blk_stat_callback;
 struct blk_crypto_profile;
@@ -195,7 +196,7 @@ struct gendisk {
 	unsigned int		nr_zones;
 	unsigned int		zone_capacity;
 	unsigned int		last_zone_capacity;
-	unsigned long __rcu	*conv_zones_bitmap;
+	u8 __rcu		*zones_cond;
 	unsigned int		zone_wplugs_hash_bits;
 	atomic_t		nr_zone_wplugs;
 	spinlock_t		zone_wplugs_lock;
@@ -432,9 +433,17 @@ struct queue_limits {
 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
 			       void *data);
 
+int disk_report_zone(struct gendisk *disk, struct blk_zone *zone,
+		     unsigned int idx, struct blk_report_zones_args *args);
+
+int blkdev_get_zone_info(struct block_device *bdev, sector_t sector,
+			 struct blk_zone *zone);
+
 #define BLK_ALL_ZONES  ((unsigned int)-1)
 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
 		unsigned int nr_zones, report_zones_cb cb, void *data);
+int blkdev_report_zones_cached(struct block_device *bdev, sector_t sector,
+		unsigned int nr_zones, report_zones_cb cb, void *data);
 int blkdev_zone_mgmt(struct block_device *bdev, enum req_op op,
 		sector_t sectors, sector_t nr_sectors);
 int blk_revalidate_disk_zones(struct gendisk *disk);
@@ -921,12 +930,20 @@ static inline unsigned int bdev_zone_capacity(struct block_device *bdev,
 {
 	return disk_zone_capacity(bdev->bd_disk, pos);
 }
+
+bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector);
+
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline unsigned int disk_nr_zones(struct gendisk *disk)
 {
 	return 0;
 }
 
+static inline bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector)
+{
+	return false;
+}
+
 static inline bool bio_needs_zone_write_plugging(struct bio *bio)
 {
 	return false;
@@ -1529,33 +1546,6 @@ static inline bool bdev_is_zone_aligned(struct block_device *bdev,
 	return bdev_is_zone_start(bdev, sector);
 }
 
-/**
- * bdev_zone_is_seq - check if a sector belongs to a sequential write zone
- * @bdev:	block device to check
- * @sector:	sector number
- *
- * Check if @sector on @bdev is contained in a sequential write required zone.
- */
-static inline bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector)
-{
-	bool is_seq = false;
-
-#if IS_ENABLED(CONFIG_BLK_DEV_ZONED)
-	if (bdev_is_zoned(bdev)) {
-		struct gendisk *disk = bdev->bd_disk;
-		unsigned long *bitmap;
-
-		rcu_read_lock();
-		bitmap = rcu_dereference(disk->conv_zones_bitmap);
-		is_seq = !bitmap ||
-			!test_bit(disk_zone_no(disk, sector), bitmap);
-		rcu_read_unlock();
-	}
-#endif
-
-	return is_seq;
-}
-
 int blk_zone_issue_zeroout(struct block_device *bdev, sector_t sector,
 			   sector_t nr_sects, gfp_t gfp_mask);
 
@@ -1662,7 +1652,8 @@ struct block_device_operations {
 	/* this callback is with swap_lock and sometimes page table lock held */
 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
 	int (*report_zones)(struct gendisk *, sector_t sector,
-			unsigned int nr_zones, report_zones_cb cb, void *data);
+			    unsigned int nr_zones,
+			    struct blk_report_zones_args *args);
 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
 	/* returns the length of the identifier or a negative errno: */
 	int (*get_unique_id)(struct gendisk *disk, u8 id[16],