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-rw-r--r--Documentation/ABI/stable/sysfs-block50
1 files changed, 49 insertions, 1 deletions
diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
index 3879963f0f01..803f578dc023 100644
--- a/Documentation/ABI/stable/sysfs-block
+++ b/Documentation/ABI/stable/sysfs-block
@@ -77,7 +77,7 @@ Description:
What: /sys/block/<disk>/diskseq
Date: February 2021
-Contact: Matteo Croce <mcroce@microsoft.com>
+Contact: Matteo Croce <teknoraver@meta.com>
Description:
The /sys/block/<disk>/diskseq files reports the disk
sequence number, which is a monotonically increasing
@@ -547,6 +547,21 @@ Description:
[RO] Maximum size in bytes of a single element in a DMA
scatter/gather list.
+What: /sys/block/<disk>/queue/max_write_streams
+Date: November 2024
+Contact: linux-block@vger.kernel.org
+Description:
+ [RO] Maximum number of write streams supported, 0 if not
+ 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@vger.kernel.org
+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
@@ -763,6 +778,39 @@ Description:
0, write zeroes is not supported by the device.
+What: /sys/block/<disk>/queue/write_zeroes_unmap_max_hw_bytes
+Date: January 2025
+Contact: Zhang Yi <yi.zhang@huawei.com>
+Description:
+ [RO] This file indicates whether a device supports zeroing data
+ in a specified block range without incurring the cost of
+ physically writing zeroes to the media for each individual
+ block. If this parameter is set to write_zeroes_max_bytes, the
+ device implements a zeroing operation which opportunistically
+ avoids writing zeroes to media while still guaranteeing that
+ subsequent reads from the specified block range will return
+ zeroed data. This operation is a best-effort optimization, a
+ device may fall back to physically writing zeroes to the media
+ due to other factors such as misalignment or being asked to
+ clear a block range smaller than the device's internal
+ allocation unit. If this parameter is set to 0, the device may
+ have to write each logical block media during a zeroing
+ operation.
+
+
+What: /sys/block/<disk>/queue/write_zeroes_unmap_max_bytes
+Date: January 2025
+Contact: Zhang Yi <yi.zhang@huawei.com>
+Description:
+ [RW] While write_zeroes_unmap_max_hw_bytes is the hardware limit
+ for the device, this setting is the software limit. Since the
+ unmap write zeroes operation is a best-effort optimization, some
+ devices may still physically writing zeroes to media. So the
+ speed of this operation is not guaranteed. Writing a value of
+ '0' to this file disables this operation. Otherwise, this
+ parameter should be equal to write_zeroes_unmap_max_hw_bytes.
+
+
What: /sys/block/<disk>/queue/zone_append_max_bytes
Date: May 2020
Contact: linux-block@vger.kernel.org