Hi, On 3/26/24 06:38, John Garry wrote: > diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block > index 1fe9a553c37b..4c775f4bdefe 100644 > --- a/Documentation/ABI/stable/sysfs-block > +++ b/Documentation/ABI/stable/sysfs-block > @@ -21,6 +21,58 @@ Description: > device is offset from the internal allocation unit's > natural alignment. > > +What: /sys/block/<disk>/atomic_write_max_bytes > +Date: February 2024 > +Contact: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> > +Description: > + [RO] This parameter specifies the maximum atomic write > + size reported by the device. This parameter is relevant > + for merging of writes, where a merged atomic write > + operation must not exceed this number of bytes. > + This parameter may be greater to the value in than > + atomic_write_unit_max_bytes as > + atomic_write_unit_max_bytes will be rounded down to a > + power-of-two and atomic_write_unit_max_bytes may also be > + limited by some other queue limits, such as max_segments. > + This parameter - along with atomic_write_unit_min_bytes > + and atomic_write_unit_max_bytes - will not be larger than > + max_hw_sectors_kb, but may be larger than max_sectors_kb. > + > + > +What: /sys/block/<disk>/atomic_write_unit_min_bytes > +Date: February 2024 > +Contact: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> > +Description: > + [RO] This parameter specifies the smallest block which can > + be written atomically with an atomic write operation. All > + atomic write operations must begin at a > + atomic_write_unit_min boundary and must be multiples of > + atomic_write_unit_min. This value must be a power-of-two. > + > + > +What: /sys/block/<disk>/atomic_write_unit_max_bytes > +Date: February 2024 > +Contact: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> > +Description: > + [RO] This parameter defines the largest block which can be > + written atomically with an atomic write operation. This > + value must be a multiple of atomic_write_unit_min and must > + be a power-of-two. This value will not be larger than > + atomic_write_max_bytes. > + > + > +What: /sys/block/<disk>/atomic_write_boundary_bytes > +Date: February 2024 > +Contact: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> > +Description: > + [RO] A device may need to internally split I/Os which > + straddle a given logical block address boundary. In that > + case a single atomic write operation will be processed as > + one of more sub-operations which each complete atomically. or > + This parameter specifies the size in bytes of the atomic > + boundary if one is reported by the device. This value must > + be a power-of-two. -- #Randy