On 3/27/23 17:40, Anuj Gupta wrote: > From: Nitesh Shetty <nj.shetty@xxxxxxxxxxx> > > Add device limits as sysfs entries, > - copy_offload (RW) > - copy_max_bytes (RW) > - copy_max_bytes_hw (RO) > > Above limits help to split the copy payload in block layer. > copy_offload: used for setting copy offload(1) or emulation(0). > copy_max_bytes: maximum total length of copy in single payload. > copy_max_bytes_hw: Reflects the device supported maximum limit. > > Reviewed-by: Hannes Reinecke <hare@xxxxxxx> > Signed-off-by: Nitesh Shetty <nj.shetty@xxxxxxxxxxx> > Signed-off-by: Kanchan Joshi <joshi.k@xxxxxxxxxxx> > Signed-off-by: Anuj Gupta <anuj20.g@xxxxxxxxxxx> > --- > Documentation/ABI/stable/sysfs-block | 36 ++++++++++++++++ > block/blk-settings.c | 24 +++++++++++ > block/blk-sysfs.c | 64 ++++++++++++++++++++++++++++ > include/linux/blkdev.h | 12 ++++++ > include/uapi/linux/fs.h | 3 ++ > 5 files changed, 139 insertions(+) > > diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block > index c57e5b7cb532..f5c56ad91ad6 100644 > --- a/Documentation/ABI/stable/sysfs-block > +++ b/Documentation/ABI/stable/sysfs-block > @@ -155,6 +155,42 @@ Description: > last zone of the device which may be smaller. > > > +What: /sys/block/<disk>/queue/copy_offload > +Date: November 2022 > +Contact: linux-block@xxxxxxxxxxxxxxx > +Description: > + [RW] When read, this file shows whether offloading copy to > + device is enabled (1) or disabled (0). Writing '0' to this ...to a device... > + file will disable offloading copies for this device. > + Writing any '1' value will enable this feature. If device If the device does... > + does not support offloading, then writing 1, will result in > + error. > + > + > +What: /sys/block/<disk>/queue/copy_max_bytes > +Date: November 2022 > +Contact: linux-block@xxxxxxxxxxxxxxx > +Description: > + [RW] While 'copy_max_bytes_hw' is the hardware limit for the > + device, 'copy_max_bytes' setting is the software limit. > + Setting this value lower will make Linux issue smaller size > + copies from block layer. This is the maximum number of bytes that the block layer will allow for a copy request. Must be smaller than or equal to the maximum size allowed by the hardware indicated by copy_max_bytes_hw. Write 0 to use the default kernel settings. > + > + > +What: /sys/block/<disk>/queue/copy_max_bytes_hw > +Date: November 2022 > +Contact: linux-block@xxxxxxxxxxxxxxx > +Description: > + [RO] Devices that support offloading copy functionality may have > + internal limits on the number of bytes that can be offloaded > + in a single operation. The `copy_max_bytes_hw` > + parameter is set by the device driver to the maximum number of > + bytes that can be copied in a single operation. Copy > + requests issued to the device must not exceed this limit. > + A value of 0 means that the device does not > + support copy offload. [RO] This is the maximum number of kilobytes supported in a single data copy offload operation. A value of 0 means that the device does not support copy offload. > + > + > What: /sys/block/<disk>/queue/crypto/ > Date: February 2022 > Contact: linux-block@xxxxxxxxxxxxxxx > diff --git a/block/blk-settings.c b/block/blk-settings.c > index 896b4654ab00..350f3584f691 100644 > --- a/block/blk-settings.c > +++ b/block/blk-settings.c > @@ -59,6 +59,8 @@ void blk_set_default_limits(struct queue_limits *lim) > lim->zoned = BLK_ZONED_NONE; > lim->zone_write_granularity = 0; > lim->dma_alignment = 511; > + lim->max_copy_sectors_hw = 0; > + lim->max_copy_sectors = 0; > } > > /** > @@ -82,6 +84,8 @@ void blk_set_stacking_limits(struct queue_limits *lim) > lim->max_dev_sectors = UINT_MAX; > lim->max_write_zeroes_sectors = UINT_MAX; > lim->max_zone_append_sectors = UINT_MAX; > + lim->max_copy_sectors_hw = ULONG_MAX; > + lim->max_copy_sectors = ULONG_MAX; > } > EXPORT_SYMBOL(blk_set_stacking_limits); > > @@ -183,6 +187,22 @@ void blk_queue_max_discard_sectors(struct request_queue *q, > } > EXPORT_SYMBOL(blk_queue_max_discard_sectors); > > +/** > + * blk_queue_max_copy_sectors_hw - set max sectors for a single copy payload > + * @q: the request queue for the device > + * @max_copy_sectors: maximum number of sectors to copy > + **/ > +void blk_queue_max_copy_sectors_hw(struct request_queue *q, > + unsigned int max_copy_sectors) > +{ > + if (max_copy_sectors >= MAX_COPY_TOTAL_LENGTH) Confusing name as LENGTH may be interpreted as bytes. MAX_COPY_SECTORS would be better. > + max_copy_sectors = MAX_COPY_TOTAL_LENGTH; > + > + q->limits.max_copy_sectors_hw = max_copy_sectors; > + q->limits.max_copy_sectors = max_copy_sectors; > +} > +EXPORT_SYMBOL_GPL(blk_queue_max_copy_sectors_hw); -- Damien Le Moal Western Digital Research