From: Christoph Hellwig <hch@xxxxxx>
Export the granularity that write streams should be discarded with,
as it is essential for making good use of them.
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Reviewed-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Signed-off-by: Kanchan Joshi <joshi.k@xxxxxxxxxxx>
---
Documentation/ABI/stable/sysfs-block | 8 ++++++++
block/blk-sysfs.c | 3 +++
include/linux/blkdev.h | 1 +
3 files changed, 12 insertions(+)
diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
index 8bbe1eca28df..4ba771b56b3b 100644
--- a/Documentation/ABI/stable/sysfs-block
+++ b/Documentation/ABI/stable/sysfs-block
@@ -555,6 +555,14 @@ Description:
supported. If supported, valid values are 1 through
max_write_streams, inclusive.
+What: /sys/block/<disk>/queue/write_stream_granularity
+Date: November 2024
+Contact: linux-block@xxxxxxxxxxxxxxx
+Description:
+ [RO] Granularity of a write stream in bytes. The granularity
+ of a write stream is the size that should be discarded or
+ overwritten together to avoid write amplification in the device.
+
What: /sys/block/<disk>/queue/max_segments
Date: March 2010
Contact: linux-block@xxxxxxxxxxxxxxx
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 986cdba4f550..ed00dedfb9ce 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -135,6 +135,7 @@ 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_streams)
+QUEUE_SYSFS_LIMIT_SHOW(write_stream_granularity)
QUEUE_SYSFS_LIMIT_SHOW(logical_block_size)
QUEUE_SYSFS_LIMIT_SHOW(physical_block_size)
QUEUE_SYSFS_LIMIT_SHOW(chunk_sectors)
@@ -490,6 +491,7 @@ QUEUE_LIM_RO_ENTRY(queue_max_segments, "max_segments");
QUEUE_LIM_RO_ENTRY(queue_max_integrity_segments, "max_integrity_segments");
QUEUE_LIM_RO_ENTRY(queue_max_segment_size, "max_segment_size");
QUEUE_LIM_RO_ENTRY(queue_max_write_streams, "max_write_streams");
+QUEUE_LIM_RO_ENTRY(queue_write_stream_granularity, "write_stream_granularity");
QUEUE_RW_ENTRY(elv_iosched, "scheduler");
QUEUE_LIM_RO_ENTRY(queue_logical_block_size, "logical_block_size");
@@ -645,6 +647,7 @@ static struct attribute *queue_attrs[] = {
&queue_max_integrity_segments_entry.attr,
&queue_max_segment_size_entry.attr,
&queue_max_write_streams_entry.attr,
+ &queue_write_stream_granularity_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 3747fbbd65fa..886009b6c3e5 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -403,6 +403,7 @@ struct queue_limits {
unsigned short max_discard_segments;
unsigned short max_write_streams;
+ unsigned int write_stream_granularity;
unsigned int max_open_zones;
unsigned int max_active_zones;
--
2.25.1
