Re: [dm-devel] [PATCH v8 1/9] block: Introduce queue limits for copy-offload support
On Wed, Mar 29, 2023 at 09:24:11PM +0900, Damien Le Moal wrote: > On 3/29/23 19:41, Nitesh Shetty wrote: > >>> +What:/sys/block//queue/copy_max_bytes > >>> +Date:November 2022 > >>> +Contact: linux-bl...@vger.kernel.org > >>> +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 > > > > Looks good. Will update in next version. We took reference from discard. > > > >>by copy_max_bytes_hw. Write 0 to use the default kernel > >>settings. > >> > > > > Nack, writing 0 will not set it to default value. (default value is > > copy_max_bytes = copy_max_bytes_hw) > > It is trivial to make it work that way, which would match how max_sectors_kb > works. Write 0 to return copy_max_bytes being equal to the default > copy_max_bytes_hw. > > The other possibility that is also interesting is "write 0 to disable copy > offload and use emulation". This one may actually be more useful. > We were following discard implementation. I feel now both options are good. We can finalize based on community feedback. > > > >>> + > >>> + > >>> +What:/sys/block//queue/copy_max_bytes_hw > >>> +Date:November 2022 > >>> +Contact: linux-bl...@vger.kernel.org > >>> +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. > >> > > > > Nack, value is in bytes. Same as discard. > > Typo. I meant Bytes. Your text is too long an too convoluted, so unclear. > Acked, will update in next version > -- > Damien Le Moal > Western Digital Research > > -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
Re: [dm-devel] [PATCH v8 1/9] block: Introduce queue limits for copy-offload support
On Wed, Mar 29, 2023 at 05:40:09PM +0900, Damien Le Moal wrote: > On 3/27/23 17:40, Anuj Gupta wrote: > > From: Nitesh Shetty > > > > 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 > > Signed-off-by: Nitesh Shetty > > Signed-off-by: Kanchan Joshi > > Signed-off-by: Anuj Gupta > > --- > > 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//queue/copy_offload > > +Date: November 2022 > > +Contact: linux-bl...@vger.kernel.org > > +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... > acked > > + file will disable offloading copies for this device. > > + Writing any '1' value will enable this feature. If device > > If the device does... > acked > > + does not support offloading, then writing 1, will result in > > + error. > > + > > + > > +What: /sys/block//queue/copy_max_bytes > > +Date: November 2022 > > +Contact: linux-bl...@vger.kernel.org > > +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 Looks good. Will update in next version. We took reference from discard. > by copy_max_bytes_hw. Write 0 to use the default kernel > settings. > Nack, writing 0 will not set it to default value. (default value is copy_max_bytes = copy_max_bytes_hw) > > + > > + > > +What: /sys/block//queue/copy_max_bytes_hw > > +Date: November 2022 > > +Contact: linux-bl...@vger.kernel.org > > +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. > Nack, value is in bytes. Same as discard. > > + > > + > > What: /sys/block//queue/crypto/ > > Date: February 2022 > > Contact: linux-bl...@vger.kernel.org > > 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, > > } > >
[dm-devel] [PATCH v8 1/9] block: Introduce queue limits for copy-offload support
From: Nitesh Shetty
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
Signed-off-by: Nitesh Shetty
Signed-off-by: Kanchan Joshi
Signed-off-by: Anuj Gupta
---
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//queue/copy_offload
+Date: November 2022
+Contact: linux-bl...@vger.kernel.org
+Description:
+ [RW] When read, this file shows whether offloading copy to
+ device is enabled (1) or disabled (0). Writing '0' to this
+ file will disable offloading copies for this device.
+ Writing any '1' value will enable this feature. If device
+ does not support offloading, then writing 1, will result in
+ error.
+
+
+What: /sys/block//queue/copy_max_bytes
+Date: November 2022
+Contact: linux-bl...@vger.kernel.org
+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.
+
+
+What: /sys/block//queue/copy_max_bytes_hw
+Date: November 2022
+Contact: linux-bl...@vger.kernel.org
+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.
+
+
What: /sys/block//queue/crypto/
Date: February 2022
Contact: linux-bl...@vger.kernel.org
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)
+ 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);
+
/**
* blk_queue_max_secure_erase_sectors - set max sectors for a secure erase
* @q: the request queue for the device
@@ -578,6 +598,10 @@ 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_copy_sectors = min(t->max_copy_sectors, b->max_copy_sectors);
+ t->max_copy_sectors_hw = min(t->max_copy_sectors_hw,
+ b->max_copy_sectors_hw);
+
t->misaligned |= b->misaligned;
alignment
Re: [dm-devel] [PATCH v8 1/9] block: Introduce queue limits for copy-offload support
On 3/29/23 19:41, Nitesh Shetty wrote: >>> +What: /sys/block//queue/copy_max_bytes >>> +Date: November 2022 >>> +Contact: linux-bl...@vger.kernel.org >>> +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 > > Looks good. Will update in next version. We took reference from discard. > >> by copy_max_bytes_hw. Write 0 to use the default kernel >> settings. >> > > Nack, writing 0 will not set it to default value. (default value is > copy_max_bytes = copy_max_bytes_hw) It is trivial to make it work that way, which would match how max_sectors_kb works. Write 0 to return copy_max_bytes being equal to the default copy_max_bytes_hw. The other possibility that is also interesting is "write 0 to disable copy offload and use emulation". This one may actually be more useful. > >>> + >>> + >>> +What: /sys/block//queue/copy_max_bytes_hw >>> +Date: November 2022 >>> +Contact: linux-bl...@vger.kernel.org >>> +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. >> > > Nack, value is in bytes. Same as discard. Typo. I meant Bytes. Your text is too long an too convoluted, so unclear. -- Damien Le Moal Western Digital Research -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
Re: [dm-devel] [PATCH v8 1/9] block: Introduce queue limits for copy-offload support
On 3/27/23 17:40, Anuj Gupta wrote:
> From: Nitesh Shetty
>
> 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
> Signed-off-by: Nitesh Shetty
> Signed-off-by: Kanchan Joshi
> Signed-off-by: Anuj Gupta
> ---
> 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//queue/copy_offload
> +Date:November 2022
> +Contact: linux-bl...@vger.kernel.org
> +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//queue/copy_max_bytes
> +Date:November 2022
> +Contact: linux-bl...@vger.kernel.org
> +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//queue/copy_max_bytes_hw
> +Date:November 2022
> +Contact: linux-bl...@vger.kernel.org
> +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//queue/crypto/
> Date:February 2022
> Contact: linux-bl...@vger.kernel.org
> 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
