rpc

Many of SPDK's RPCs were renamed to be more consistent and intuitive in this release.
The old names will continue to function, but will display a deprecation warning.

Added optional parameters '--arbitration-burst' and '--low/medium/high-priority-weight' to
'bdev_nvme_set_options' RPC method.

Added optional parameter '--md-size' to 'construct_null_bdev' RPC method.

Added optional parameters '--dif-type' and '--dif-is-head-of-md' to 'construct_null_bdev'
RPC method.

Added blobfs_detect RPC method to detect whether a blobfs exists on given bdev.

Added blobfs_create RPC method to build blobfs on given bdev.

Added blobfs_mount RPC method to mount blobfs on given bdev to a host path by FUSE.
Then on the host path, user can directly do some file operations which will be mapped
to blobfs.

bdev

Added new parameter cdw0 to spdk_bdev_io_complete_nvme_status() and
spdk_bdev_io_get_nvme_status() that allows setting/getting
the NVMe completion queue DW0 entry. This allows vendor specific IO commands
to return commmand specific completion info back to the initiator.

Added spdk_bdev_get_write_unit_size() function for retrieving required number
of logical blocks for write operation.

New zone-related fields were added to the result of the get_bdevs RPC call:

• zoned: indicates whether the device is zoned or a regular
  block device
• zone_size: number of blocks in a single zone
• max_open_zones: maximum number of open zones
• optimal_open_zones: optimal number of open zones
  The zoned field is a boolean and is always present, while the rest is only available for zoned
  bdevs.

A new spdk_bdev_open_ext function has been added and spdk_bdev_open function has been deprecated.
The new open function introduces requirement to provide callback function that will be called by
asynchronous event such as bdev removal. spdk_bdev_open_ext function takes bdev name as
an argument instead of bdev structure to avoid a race condition that can happen when the bdev
is being removed between a call to get its structure based on a name and actually openning it.

New 'resize' event has been added to notify about change of block count property of block device.
Event is delivered only if block device was opened with spdk_bdev_open_ext function.

bdev zone

Added new public header for zoned bdev. Zoned bdev is an extension
of the bdev interface.

spdk_bdev_get_zone_size(), spdk_bdev_get_max_open_zones(), spdk_bdev_get_optimal_open_zones()
APIs were added for retrieving zoned device information.
spdk_bdev_get_zone_info() API was added for retrieving information about zones in zoned
device.
Added spdk_bdev_zone_management() API for changing zone state.
spdk_bdev_zone_append() and spdk_bdev_zone_append_with_md() APIs were added for
appending data to a zone.
Added spdk_bdev_io_get_append location() function for retrieving append location for I/O.
Added spdk_bdev_is_zoned() function for checking if bdev supports zoned namespace semantics.

bdev opal

EXPERIMENTAL: A new opal bdev has been added to support management of
NVMe self-encrypting drives through the Opal specification. Users can
create opal bdevs from an NVMe namespace bdev, if the controller
containing that namespace supports Opal. Currently this is only
supported for namespace ID=1. The following RPCs have been added to
support Opal: bdev_nvme_opal_init, bdev_nvme_opal_revert,
bdev_opal_create, bdev_opal_delete, bdev_opal_get_info,
bdev_opal_new_user, bdev_opal_set_lock_state.
It does not yet support recreating the opal bdevs after application restart.
This bdev module should be considered very experimental, and the RPCs may
change significantly in future releases.

delay bdev

The bdev_delay_update_latency has been added to allow users to update
a latency value for a given delay bdev.

compress bdev

A new RPC bdev_compress_get_orphans has been added to list compress bdevs
that were not loaded due to a missing pm metadata file. In this state they
can only be deleted.

null bdev

Metadata support has been added to Null bdev module.

Protection information support has been added to Null bdev module.

nvme

Added no_shn_notification to NVMe controller initialization options, users can enable
it for NVMe controllers. When the option is enabled, the controller will not do the
shutdown process and just disable the controller, users can start their application
later again to initialize the controller to the ready state.

A controller flag SPDK_NVME_CTRLR_WRR_SUPPORTED was added to indicate the controller
can support weighted round robin arbitration feature with submission queue.

Added arbitration_burst option for arbitration feature, and added three
low/medium/high_priority_weight options for weighted round robin arbitration.

Added spdk_nvme_ns_cmd_write_uncorrectable.

Added new error handling and reporting functionality. This includes several
new API functions to facilitate applications recovering when a qpair or
controller fails.

spdk_nvme_ctrlr_reconnect_io_qpair - Reconnects a failed I/O qpair.
spdk_nvme_ctrlr_set_trid - Sets the trid of an existing controller. Can be used to
change the trid for failover cases.
spdk_nvme_ctrlr_is_failed - Returns the failed state of a controller.
spdk_nvme_ctrlr_fail - Forces a controller into a failed state.

Modified the return behavior of several API functions to better indicate to
applications when a qpair is failed. This list of functions includes:

spdk_nvme_qpair_process_completions
spdk_nvme_ns_cmd_*
spdk_nvme_ctrlr_process_admin_completions
spdk_nvme_ctrlr_cmd_*

These functions now return -ENXIO when the qpair or controller on which they
operate is failed.

EXPERIMENTAL: Added NVMe character device support to allow to create NVMe device nodes in Linux
kernel for controller as well as for namespace and process ioctl requests as usual
from linux environment.

nvmf

The spdk_nvmf_tgt_create function now accepts an object of type spdk_nvmf_target_opts
as its only parameter. This new structure contains the max_subsystems parameter previously
passed into that function.

A new public API function spdk_nvmf_get_tgt has been added which allows users to
retrieve a pointer to an spdk_nvmf_tgt object by supplying its name. In the special
case where an RPC or application only creates a single target, this function can accept
a null name parameter and will return the only available target.

The majority of the NVMe-oF RPCs now accept an optional tgt_name parameter. This will
allow those RPCs to work with applications that create more than one target.

Three new NVMe-oF RPCs have been added nvmf_create_target, nvmf_delete_target, and
nvmf_get_targets. These new RPCs provide a basic interface for managing multiple target
objects. In SPDK the target object defines a unique discovery service. As of this release,
these RPCs are not intended to be used with the in-tree SPDK target applications, spdk_tgt and
nvmf_tgt, which use a single, global target structure. As such, they are not included in scripts/rpc.py

Three new header functions have also been added to help deal with multiple targets.
spdk_nvmf_tgt_get_name takes a target pointer as an argument and returns its human readable name.
spdk_nvmf_get_first_target takes no arguments and returns the first target in the global list.
spdk_nvmf_get_next_tgt takes a target pointer as an argument and returns the next one in the global list.

The spdk_nvmf_tgt_accept takes additional argument allowing to pass arbitrary context
information to the new_qpair callback. This will simplify the code when having multiple
nvmf targets or when retrieving the context information from globals is not suitable.

blobstore

A new spdk_bdev_create_bs_dev_from_desc function has been added and spdk_bdev_create_bs_dev
function has been deprecated.
The new create function can cowork with spdk_bdev_open_ext function, which provides callback
function that will be called by asynchronous event such as bdev removal.

blobfs_bdev

A new blobfs module bdev has been added to simplify the operations of blobfs on bdev.

Function spdk_blobfs_bdev_detect is added to detect whether blobfs exists on the given block device.

Function spdk_blobfs_bdev_create is added to create a blobfs on the given block device.

Function spdk_blobfs_bdev_mount is added to mount a blobfs on the given block device to
a host path by FUSE. Then, a new thread is created dedicatedly for one mountpoint to handle
FUSE request by blobfs API.

build

Option to build FUSE components into blobfs_bdev module for mounting a blobfs filesystem.
It requires the installation of libfuse3. By default, it is disabled. And it will be
enabled if run ./configure with --with-fuse option.

iSCSI

Portals may no longer be associated with a cpumask. The scheduling of
connections is moving to a more dynamic model.

An new RPC iscsi_portal_group_set_auth has been added to set CHAP authentication
for discovery sessions specific for the existing iSCSI portal group. This RPC overwrites
the setting by the global parameters for the iSCSI portal group.

socket

Added spdk_sock_is_connected to check whether the socket is currently connected.
spdk_sock_group_poll now returns number of events on success.

env

Added spdk_pci_device_unclaim() function to cleanup pci claim file.

event

framework_start_init RPC no longer stops the application on error during
initialization.

DPDK

Updated DPDK submodule to DPDK 19.08.

ocf

Updated OCF submodule to OCF v19.06

Along with update, new cache mode 'write only' was added.

New cache modes added to use via RPC, wi - write invalidate and wa - write around.

New version of OCF provides fully asynchronous management API.