[RFC PATCH 0/2] add simple copy support

From: SelvaKumar S
Date: Tue Dec 01 2020 - 02:12:55 EST


This patchset tries to add support for TP4065a ("Simple Copy Command"),
v2020.05.04 ("Ratified")

The Specification can be found in following link.
https://nvmexpress.org/wp-content/uploads/NVM-Express-1.4-Ratified-TPs-1.zip

This is an RFC. Looking forward for any feedbacks or other alternate
designs for plumbing simple copy to IO stack.

Simple copy command is a copy offloading operation and is used to copy
multiple contiguous ranges (source_ranges) of LBA's to a single destination
LBA within the device reducing traffic between host and device.

This implementation accepts destination, no of sources and arrays of
source ranges from application and attach it as payload to the bio and
submits to the device.

Following limits are added to queue limits and are exposed in sysfs
to userspace
- *max_copy_sectors* limits the sum of all source_range length
- *max_copy_nr_ranges* limits the number of source ranges
- *max_copy_range_sectors* limit the maximum number of sectors
that can constitute a single source range.


SelvaKumar S (2):
block: add simple copy support
nvme: add simple copy support

block/blk-core.c | 104 +++++++++++++++++++++++++++++++---
block/blk-lib.c | 116 ++++++++++++++++++++++++++++++++++++++
block/blk-merge.c | 2 +
block/blk-settings.c | 11 ++++
block/blk-sysfs.c | 23 ++++++++
block/blk-zoned.c | 1 +
block/bounce.c | 1 +
block/ioctl.c | 43 ++++++++++++++
drivers/nvme/host/core.c | 91 ++++++++++++++++++++++++++++++
drivers/nvme/host/nvme.h | 4 ++
include/linux/bio.h | 1 +
include/linux/blk_types.h | 7 +++
include/linux/blkdev.h | 15 +++++
include/linux/nvme.h | 45 +++++++++++++--
include/uapi/linux/fs.h | 21 +++++++
15 files changed, 473 insertions(+), 12 deletions(-)

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2.25.1