From f70291411ba20d50008db90a6f0731efac27872c Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Wed, 25 Jun 2025 18:33:24 +0900 Subject: block: Introduce bio_needs_zone_write_plugging() In preparation for fixing device mapper zone write handling, introduce the inline helper function bio_needs_zone_write_plugging() to test if a BIO requires handling through zone write plugging using the function blk_zone_plug_bio(). This function returns true for any write (op_is_write(bio) == true) operation directed at a zoned block device using zone write plugging, that is, a block device with a disk that has a zone write plug hash table. This helper allows simplifying the check on entry to blk_zone_plug_bio() and used in to protect calls to it for blk-mq devices and DM devices. Fixes: f211268ed1f9 ("dm: Use the block layer zone append emulation") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250625093327.548866-3-dlemoal@kernel.org Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) (limited to 'include') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5c626d23cbb2..a51f92b6c340 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -837,6 +837,55 @@ static inline unsigned int disk_nr_zones(struct gendisk *disk) { return disk->nr_zones; } + +/** + * bio_needs_zone_write_plugging - Check if a BIO needs to be handled with zone + * write plugging + * @bio: The BIO being submitted + * + * Return true whenever @bio execution needs to be handled through zone + * write plugging (using blk_zone_plug_bio()). Return false otherwise. + */ +static inline bool bio_needs_zone_write_plugging(struct bio *bio) +{ + enum req_op op = bio_op(bio); + + /* + * Only zoned block devices have a zone write plug hash table. But not + * all of them have one (e.g. DM devices may not need one). + */ + if (!bio->bi_bdev->bd_disk->zone_wplugs_hash) + return false; + + /* Only write operations need zone write plugging. */ + if (!op_is_write(op)) + return false; + + /* Ignore empty flush */ + if (op_is_flush(bio->bi_opf) && !bio_sectors(bio)) + return false; + + /* Ignore BIOs that already have been handled by zone write plugging. */ + if (bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING)) + return false; + + /* + * All zone write operations must be handled through zone write plugging + * using blk_zone_plug_bio(). + */ + switch (op) { + case REQ_OP_ZONE_APPEND: + case REQ_OP_WRITE: + case REQ_OP_WRITE_ZEROES: + case REQ_OP_ZONE_FINISH: + case REQ_OP_ZONE_RESET: + case REQ_OP_ZONE_RESET_ALL: + return true; + default: + return false; + } +} + bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs); /** @@ -866,6 +915,12 @@ static inline unsigned int disk_nr_zones(struct gendisk *disk) { return 0; } + +static inline bool bio_needs_zone_write_plugging(struct bio *bio) +{ + return false; +} + static inline bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs) { return false; -- cgit v1.2.3