From ccdbf0aad2523ca133cceb22ce0f8306730e7ac3 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Mon, 8 Apr 2024 10:41:09 +0900 Subject: block: Allow zero value of max_zone_append_sectors queue limit In preparation for adding a generic zone append emulation using zone write plugging, allow device drivers supporting zoned block device to set a the max_zone_append_sectors queue limit of a device to 0 to indicate the lack of native support for zone append operations and that the block layer should emulate these operations using regular write operations. blk_queue_max_zone_append_sectors() is modified to allow passing 0 as the max_zone_append_sectors argument. The function queue_max_zone_append_sectors() is also modified to ensure that the minimum of the max_hw_sectors and chunk_sectors limit is used whenever the max_zone_append_sectors limit is 0. This minimum is consistent with the value set for the max_zone_append_sectors limit by the function blk_validate_zoned_limits() when limits for a queue are validated. The helper functions queue_emulates_zone_append() and bdev_emulates_zone_append() are added to test if a queue (or block device) emulates zone append operations. In order for blk_revalidate_disk_zones() to accept zoned block devices relying on zone append emulation, the direct check to the max_zone_append_sectors queue limit of the disk is replaced by a check using the value returned by queue_max_zone_append_sectors(). Similarly, queue_zone_append_max_show() is modified to use the same accessor so that the sysfs attribute advertizes the non-zero limit that will be used, regardless if it is for native or emulated commands. For stacking drivers, a top device should not need to care if the underlying devices have native or emulated zone append operations. blk_stack_limits() is thus modified to set the top device max_zone_append_sectors limit using the new accessor queue_limits_max_zone_append_sectors(). queue_max_zone_append_sectors() is modified to use this function as well. Stacking drivers that require zone append emulation, e.g. dm-crypt, can still request this feature by calling blk_queue_max_zone_append_sectors() with a 0 limit. Signed-off-by: Damien Le Moal Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Reviewed-by: Bart Van Assche Tested-by: Hans Holmberg Tested-by: Dennis Maisenbacher Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20240408014128.205141-10-dlemoal@kernel.org Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 348b57ca0425..46613bf6a402 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1173,12 +1173,29 @@ static inline unsigned int queue_max_segment_size(const struct request_queue *q) return q->limits.max_segment_size; } -static inline unsigned int queue_max_zone_append_sectors(const struct request_queue *q) +static inline unsigned int queue_limits_max_zone_append_sectors(struct queue_limits *l) { + unsigned int max_sectors = min(l->chunk_sectors, l->max_hw_sectors); - const struct queue_limits *l = &q->limits; + return min_not_zero(l->max_zone_append_sectors, max_sectors); +} + +static inline unsigned int queue_max_zone_append_sectors(struct request_queue *q) +{ + if (!blk_queue_is_zoned(q)) + return 0; - return min(l->max_zone_append_sectors, l->max_sectors); + return queue_limits_max_zone_append_sectors(&q->limits); +} + +static inline bool queue_emulates_zone_append(struct request_queue *q) +{ + return blk_queue_is_zoned(q) && !q->limits.max_zone_append_sectors; +} + +static inline bool bdev_emulates_zone_append(struct block_device *bdev) +{ + return queue_emulates_zone_append(bdev_get_queue(bdev)); } static inline unsigned int -- cgit v1.2.3