From: Keith Busch <kbusch@xxxxxxxxxx> Drivers with hardware that support write streams need a way to export how many are available so applications can generically query this. Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx> --- Documentation/ABI/stable/sysfs-block | 7 +++++++ block/blk-settings.c | 3 +++ block/blk-sysfs.c | 3 +++ include/linux/blkdev.h | 12 ++++++++++++ 4 files changed, 25 insertions(+) diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block index 8353611107154..f2db2cabb8e75 100644 --- a/Documentation/ABI/stable/sysfs-block +++ b/Documentation/ABI/stable/sysfs-block @@ -506,6 +506,13 @@ Description: [RO] Maximum size in bytes of a single element in a DMA scatter/gather list. +What: /sys/block/<disk>/queue/max_write_hints +Date: October 2024 +Contact: linux-block@xxxxxxxxxxxxxxx +Description: + [RO] Maximum number of write hints supported, 0 if not + supported. If supported, valid values are 1 through + max_write_hints, inclusive. What: /sys/block/<disk>/queue/max_segments Date: March 2010 diff --git a/block/blk-settings.c b/block/blk-settings.c index a446654ddee5e..921fb4d334fa4 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -43,6 +43,7 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; /* Inherit limits from component devices */ + lim->max_write_hints = USHRT_MAX; lim->max_segments = USHRT_MAX; lim->max_discard_segments = USHRT_MAX; lim->max_hw_sectors = UINT_MAX; @@ -544,6 +545,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, t->max_segment_size = min_not_zero(t->max_segment_size, b->max_segment_size); + t->max_write_hints = min(t->max_write_hints, b->max_write_hints); + alignment = queue_limit_alignment_offset(b, start); /* Bottom device has different alignment. Check that it is diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 741b95dfdbf6f..85f48ca461049 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -104,6 +104,7 @@ QUEUE_SYSFS_LIMIT_SHOW(max_segments) QUEUE_SYSFS_LIMIT_SHOW(max_discard_segments) QUEUE_SYSFS_LIMIT_SHOW(max_integrity_segments) QUEUE_SYSFS_LIMIT_SHOW(max_segment_size) +QUEUE_SYSFS_LIMIT_SHOW(max_write_hints) QUEUE_SYSFS_LIMIT_SHOW(logical_block_size) QUEUE_SYSFS_LIMIT_SHOW(physical_block_size) QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors) @@ -457,6 +458,7 @@ QUEUE_RO_ENTRY(queue_max_hw_sectors, "max_hw_sectors_kb"); QUEUE_RO_ENTRY(queue_max_segments, "max_segments"); QUEUE_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments"); QUEUE_RO_ENTRY(queue_max_segment_size, "max_segment_size"); +QUEUE_RO_ENTRY(queue_max_write_hints, "max_write_hints"); QUEUE_RW_LOAD_MODULE_ENTRY(elv_iosched, "scheduler"); QUEUE_RO_ENTRY(queue_logical_block_size, "logical_block_size"); @@ -591,6 +593,7 @@ static struct attribute *queue_attrs[] = { &queue_max_discard_segments_entry.attr, &queue_max_integrity_segments_entry.attr, &queue_max_segment_size_entry.attr, + &queue_max_write_hints_entry.attr, &queue_hw_sector_size_entry.attr, &queue_logical_block_size_entry.attr, &queue_physical_block_size_entry.attr, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index d0a52ed05e60c..90a19ea889276 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -394,6 +394,8 @@ struct queue_limits { unsigned short max_integrity_segments; unsigned short max_discard_segments; + unsigned short max_write_hints; + unsigned int max_open_zones; unsigned int max_active_zones; @@ -1189,6 +1191,11 @@ static inline unsigned short queue_max_segments(const struct request_queue *q) return q->limits.max_segments; } +static inline unsigned short queue_max_write_hints(struct request_queue *q) +{ + return q->limits.max_write_hints; +} + static inline unsigned short queue_max_discard_segments(const struct request_queue *q) { return q->limits.max_discard_segments; @@ -1236,6 +1243,11 @@ static inline unsigned int bdev_max_segments(struct block_device *bdev) return queue_max_segments(bdev_get_queue(bdev)); } +static inline unsigned short bdev_max_write_hints(struct block_device *bdev) +{ + return queue_max_write_hints(bdev_get_queue(bdev)); +} + static inline unsigned queue_logical_block_size(const struct request_queue *q) { return q->limits.logical_block_size; -- 2.43.5