block: pre-calculate max_zone_append_sectors
max_zone_append_sectors differs from all other queue limits in that the
final value used is not stored in the queue_limits but needs to be
obtained using queue_limits_max_zone_append_sectors helper. This not
only adds (tiny) extra overhead to the I/O path, but also can be easily
forgotten in file system code.
Add a new max_hw_zone_append_sectors value to queue_limits which is
set by the driver, and calculate max_zone_append_sectors from that and
the other inputs in blk_validate_zoned_limits, similar to how
max_sectors is calculated to fix this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20241108154657.845768-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 859875a..7b0af83 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -392,11 +392,10 @@ struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
struct bio *bio_split_zone_append(struct bio *bio,
const struct queue_limits *lim, unsigned *nr_segs)
{
- unsigned int max_sectors = queue_limits_max_zone_append_sectors(lim);
int split_sectors;
split_sectors = bio_split_rw_at(bio, lim, nr_segs,
- max_sectors << SECTOR_SHIFT);
+ lim->max_zone_append_sectors << SECTOR_SHIFT);
if (WARN_ON_ONCE(split_sectors > 0))
split_sectors = -EINVAL;
return bio_submit_split(bio, split_sectors);
