CHANGELOG: refactor initial changelog entries

## v21.04: (Upcoming Release)

### accel

### virtio

Add the bdev_virtio_blk_set_hotplug rpc for the virtio blk pci device.

### ocf

Updated OCF submodule to v20.12.2

### nvme

Added an accelerated table pointer in spdk_nvme_poll_group

which can be used provide the accelerated functions by users with

hardware engine, such as crc32c accelerated function.

Added `spdk_nvme_map_cmd` API to map the NVMe command with SGL cases.

### raid

For `bdev_raid_create` RPC, the deprecated parameter `strip_size` was removed.

Two new accelerated crc32 functions `spdk_accel_submit_crc32cv` and

`spdk_accel_batch_prep_crc32cv` are added in order to provide the

chained accelerated CRC32 computation support.

### bdev

### env

Added spdk_pci_device_allow API to allow applications to add PCI addresses to

Added `spdk_pci_device_allow` API to allow applications to add PCI addresses to

the allowed list after the application has started.

Removed the `pci_whitelist`, `pci_blacklist` and `master_core` members of struct `spdk_env_opts`.

Removed the `config_file`, `max_delay_us`, `pci_whitelist`

and `pci_blacklist` members of struct `spdk_app_opts`.

### thread

### idxd

Added `spdk_thread_set_interrupt_mode` function in order to set present spdk_thead into

interrupt mode or back to poll mode. It is valid only when thread interrupt facility is

enabled by spdk_interrupt_mode_enable().

A new API `spdk_idxd_get_rebalance` was added so that users of the library

can know whether they need to rebalance the flow control for the channel

that was just added/removed.  This is based on how the low level library

shares devices amongst channels.

Added `spdk_poller_register_interrupt` function to mark that the poller is capable of

entering interrupt mode. Callback function will be called when the poller must transition

into or out of interrupt mode.

The API `spdk_idxd_reconfigure_chan` had the `num_channels` removed as this

is now tracked in the library.  The app makes use the new API above to

determine whether to rebalance or not. This applies to `spdk_idxd_configure_chan`

as well.

The API `spdk_idxd_put_channel` now returns the rebalance state for the

underlying device.

### iscsi

and crash the SPDK iSCSI target process. All users of the SPDK iSCSI target

are recommended to update. All SPDK versions <= v21.01 are affected.

### accel

Two new accelerated crc32 functions 'spdk_accel_submit_crc32cv' and

'spdk_accel_batch_prep_crc32cv' are added in order to provide the

chained accelerated CRC32 computation support.

### net

The net library is deprecated and will be removed in the 21.07 release.

### nvme

Added a new function `spdk_nvme_ctrlr_get_regs_pmrcap` to get the PMR capabilities.

Added an accelerated table pointer in `spdk_nvme_poll_group`

which can be used to provide the accelerated functions by users with

hardware engine, such as crc32c accelerated function.

Added new functions `spdk_nvme_ctrlr_get_pmrsz`, `spdk_nvme_ctrlr_enable_pmr`,

`spdk_nvme_ctrlr_disable_pmr`, `spdk_nvme_ctrlr_map_pmr` and `spdk_nvme_ctrlr_unmap_pmr`.

function pointer in spdk_nvmf_transport_ops structure in order to add the qpair to the most

suitable polling group.

Add OPTPERF and namespace optimal performance fields to nvme_spec.h.

Added OPTPERF and namespace optimal performance fields to nvme_spec.h.

Added spdk_nvme_set_hotplug_filter API to allow applications to choose which

Added `spdk_nvme_set_hotplug_filter` API to allow applications to choose which

hot-inserted SSDs should be probed. This is useful for use cases where multiple

independent SPDK processes are running on one node. The filter function can

then be implemented in these processes to decide which SSDs to probe based on

the new SSD's PCI address.

New functions `spdk_nvme_poll_group_get_stats` and `spdk_nvme_poll_group_free_stats`

added. These functions allow to get transport statistics per NVME poll group.

were added. These functions allow to get transport statistics per NVME poll group.

Added `spdk_nvme_map_cmd` API to map the NVMe command with SGL cases.

### nvmf

Removed the `spdk_nvmf_tgt_listen` and `spdk_nvmf_subsystem_add_ns` API.

Added new APIs:

- `spdk_nvmf_poll_group_dump_stat` (function in `nvmf.h`).

- `poll_group_dump_stat` (transport op in `nvmf_transport.h`).

The following APIs have been deprecated and will be removed in a future release:

- `spdk_nvmf_poll_group_get_stat` (function in `nvmf.h`),

- `spdk_nvmf_transport_poll_group_get_stat` (function in `nvmf.h`),

- `spdk_nvmf_transport_poll_group_free_stat`(function in `nvmf.h`),

The `trtype` field in JSON returned by `nvmf_get_stats` RPC contains now the name of the transport,

which is the same as the type for defined transports and more informative for a custom transport.

### opal

### ocf

Removed the `spdk_opal_supported` API.

Updated OCF submodule to v20.12.2

### sock

### opal

The type of enable_placement_id in struct spdk_sock_impl_opts is changed from

bool to int. We can use RPC to configure different value of enable_placement_id.

Then we can leverage SO_INCOMING_CPU to get placement_id, which aims to utilize

CPU cache locality, enabled by setting enable_placement_id=2.

Removed the `spdk_opal_supported` API.

### thread

### raid

A new API `spdk_io_channel_get_io_device` was added to get the io_device for the specified

I/O channel.

For `bdev_raid_create` RPC, the deprecated parameter `strip_size` was removed.

### rpc

SPDK. The pkg/spdk.spec is considered to be deprecated and scheduled for removal. See

[RPM documentation](https://spdk.io/doc/rpm.html) for more details.

## v21.01:

### sock

### idxd

The type of `enable_placement_id` in struct `spdk_sock_impl_opts` is changed from

bool to int. We can use RPC to configure different value of `enable_placement_id`.

Then we can leverage SO_INCOMING_CPU to get placement_id, which aims to utilize

CPU cache locality, enabled by setting enable_placement_id=2.

A new API `spdk_idxd_get_rebalance` was added so that users of the library

can know whether they need to rebalance the flow control for the channel

that was just added/removed.  This is based on how the low level library

shares devices amongst channels.

### thread

The API `spdk_idxd_reconfigure_chan` had the `num_channels` removed as this

is now tracked in the library.  The app makes use the new API above to

determine whether to rebalance or not. This applies to `spdk_idxd_configure_chan`

as well.

A new API `spdk_io_channel_get_io_device` was added to get the io_device for the specified

I/O channel.

The API `spdk_idxd_put_channel` now returns the rebalance state for the

underlying device.

Added `spdk_thread_set_interrupt_mode` function in order to set present spdk_thread into

interrupt mode or back to poll mode. It is valid only when thread interrupt facility is

enabled by `spdk_interrupt_mode_enable`.

Added `spdk_poller_register_interrupt` function to mark that the poller is capable of

entering interrupt mode. Callback function will be called when the poller must transition

into or out of interrupt mode.

### virtio

Added the `bdev_virtio_blk_set_hotplug` RPC for the virtio blk pci device.

## v21.01:

### bdev

### nvme

Added a new function `spdk_nvme_ctrlr_get_regs_pmrcap` to get the PMR capabilities.

Directives support was added to the NVMe driver.

Two async APIs `spdk_nvme_ctrlr_cmd_directive_receive` and `spdk_nvme_ctrlr_cmd_directive_send`