xref: /spdk/CHANGELOG.md (revision ec6d94b67409a852cb576cdcdb446ba028295041)
1# Changelog
2
3## v23.01: (Upcoming Release)
4
5### bdev
6
7Both of interleaved and separated metadata are now supported by the malloc bdev module.
8
9Protection information is now supported by the malloc bdev module.
10
11A new API `spkd_bdev_part_submit_request_ext` was added to specify a custom completion callback.
12
13### scheduler
14
15Changing scheduler from dynamic back to static is no longer possible,
16as there is no way of saving original SPDK thread distribution on reactors.
17
18### bdev
19
20New APIs `spdk_bdev_for_each_channel` and `spdk_bdev_for_each_channel_continue` and
21associated function pointers were added to iterate each channel of the required bdev.
22
23The RPC `bdev_get_iostat` now allows a user to query the per channel IO statistics for
24required bdev.
25
26New `spdk_bdev_copy_blocks` and `spdk_bdev_get_max_copy` APIs to support copy commands.
27
28A new API `spdk_bdev_io_get_submit_tsc` was added to get the submit_tsc of the bdev I/O.
29
30Bdevs will no longer have UUIDs generated based on timestamp and are responsible for
31setting this field themselves. Generation of UUIDs for NVMe bdevs may be enabled by
32running `bdev_nvme_set_options` RPC with `--generate-uuids` option. These identifiers
33are based on serial number and namespace ID and will always be the same for a given
34device.
35
36A new API `spdk_bdev_channel_get_histogram` was added to get the histogram of a specified
37channel for a bdev.
38
39Converted internal use of `pthread_mutex_t` to `struct spdk_spinlock`. Consumers of bdev
40API functions must be on an SPDK thread or the program will abort. It is now enforced
41that no internal bdev locks can be held when a poller or message goes off CPU.
42
43### event
44
45Added core lock file mechanism to prevent the same CPU cores from being used by multiple
46SPDK application instances.
47
48Added a command line switch to disable CPU locks on SPDK startup.
49
50Added RPCs framework_enable_cpumask_locks and framework_disable_cpumask_locks to enable
51and disable CPU core locks in runtime.
52
53Added --rpcs-allowed command line option. Users can specify a comma-separated list of RPC
54names with this option to restrict allowed RPCs to only that list.
55
56### rpc
57
58Added spdk_rpc_set_allowlist to restrict allowed RPCs to the specified list.
59
60Changed `bdev_raid_get_bdevs` RPC output format to include raid_bdev details.
61
62### bdevperf
63
64Promoted the application to example to match similar programs: fio_plugin and perf.
65It can now be found inside `examples/bdev/bdevperf`.
66
67### trace
68
69New `trace_get_info` RPC was added to get name of shared memory file, list of the
70available trace point groups and mask of the available trace points for each group.
71
72### util
73
74New API `spdk_fd_group_get_epoll_event` that returns the epoll(7) event that
75caused a function callback in file descriptor group to execute.
76
77### json
78
79Added API `spdk_json_write_double` and `spdk_json_write_named_double` to allow
80for writing and decoding of the the double data type.
81
82### thread
83
84Added `spdk_thread_get_app_thread` which returns the first thread that was created using
85`spdk_thread_create`.
86
87Added `spdk_thread_is_running`.  This returns `true` for a running thread, or `false` if
88its exit process has started using `spdk_thread_exit`.
89
90Added API `spdk_spin_init`, `spdk_spin_destroy`, `spdk_spin_lock`, `spdk_spin_unlock`, and
91`spdk_spin_held` to support spinlocks that are aware of the SPDK concurrency model.
92
93## v22.09
94
95### accel
96
97Many names were changed in the accel framework to make them consistent both with themselves and
98the rest of SPDK. The primary public header file is now named `include/spdk/accel.h`.
99
100Added a new runtime RPC `accel_get_opc_assignments` to get a list of current opcode to engine
101assignments.
102
103Added a new startup RPC `accel_assign_opc` to assign/override a specific opcode to
104an engine.
105
106### bdev
107
108New RPCs `bdev_xnvme_create` and `bdev_xnvme_delete` were added to support the xNVMe bdev.
109
110A new API `spdk_bdev_for_each_bdev_io` was added to execute the function on the appropriate
111thread for each bdev_io submitted to the bdev.
112
113A new API `spdk_bdev_get_current_qd` was added to measure and return the queue depth from a
114bdev. This API is available even when queue depth sampling is disabled.
115
116Added `spdk_bdev_seek_data`, `spdk_bdev_seek_hole` and `spdk_bdev_io_get_seek_offset` functions
117that start from a given offset and seek for next data or for next hole. At this time only
118supported by lvol bdev module.
119
120A new parameter `io_drain_timeout` has been added to `spdk_bdev` structure. It controls how long
121a bdev reset must wait for IO to complete prior to issuing a reset to the underlying device.
122If there is no outstanding IO at the end of that period, the reset is skipped.
123Best defined for bdevs that share an underlying bdev, such as multiple lvol bdevs sharing
124an nvme device, to avoid unnecessarily resetting the underlying bdev and affecting other
125bdevs that are sharing it.
126Modifying this field is optional. Setting the value to 0 keeps the original behavior
127to always send resets immediately, even if there is no I/O outstanding.
128
129### blobstore
130
131Reserve space for `used_clusters` bitmap. The reserved space could be used for blobstore growing
132in the future.
133
134Added `is_zeroes` operation to `spdk_bs_dev`. It allows to detect if logical blocks are backed
135by zeroes device and do a shortcut in copy-on-write flow by excluding copy part from zeroes device.
136
137Added `spdk_blob_get_next_allocated_io_unit` and `spdk_blob_get_next_unallocated_io_unit` functions
138that start from a given offset and seek for first io_unit belonging to an allocated cluster
139or first io_unit belonging to an unallocated cluster.
140
141Added `spdk_bs_grow` function to grow blobstore size if the underlying bdev size is increased.
142This is used by lvol bdev via `bdev_lvol_grow_lvstore` RPC.
143
144### daos
145
146Added new DAOS bdev module, that creates SPDK block device on top of DAOS DFS.
147Please see [documentation](https://spdk.io/doc/bdev.html#bdev_config_daos) for more details.
148
149### env
150
151Added `spdk_pci_register_device_provider` and matching `SPDK_PCI_REGISTER_DEVICE_PROVIDER`
152functions for registering PCI device providers. That allow the VMD driver to be notified
153when users want to attach a device under a given BDF and when a device is detached.
154
155### init
156
157`spdk_subsystem_init_from_json_config` now fails if the JSON configuration file is not
158an object with an array named "subsystems".
159
160### iscsi
161
162Added `bdev_iscsi_set_options` RPC to modify options of the iSCSI bdev module.
163
164### json
165
166Added `spdk_json_find` API return errcode: EPROTOTYPE - json not enclosed in {}.
167`spdk_json_find` now returns -EPROTOTYPE instead of -ENOENT if the object parameter
168does not point to a JSON object (i.e. is not enclosed with {}).
169
170### lvol
171
172Add `num_md_pages_per_cluster_ratio` parameter to the `bdev_lvol_create_lvstore` RPC.
173Calculate `num_md_pages` from `num_md_pages_per_cluster_ratio`, and pass it to `spdk_bs_opts`.
174
175### nvme
176
177Added SPDK_NVME_TRANSPORT_CUSTOM_FABRICS to enum `spdk_nvme_transport_type` to support custom
178fabric transport. SPDK_NVME_TRANSPORT_CUSTOM was intended to be non-fabric custom transport.
179
180Added a new function `spdk_nvme_ns_cmd_verify` to submit a Verify Command to a Namespace.
181
182Added `spdk_nvme_ctrlr_disable_read_changed_ns_list_log_page` to allow an application to
183tell the driver to not read the CHANGED_NS_LIST log page in response to a NS_ATTR_CHANGED
184AEN.  When called the application is required to read this log page instead to clear the
185AEN.
186
187Added `psk` field to `spdk_nvme_ctrlr_opts` struct in order to enable SSL socket implementation
188of TCP connection and set the PSK. Applicable for TCP transport only.
189
190### raid
191
192Renamed the `raid5` module to `raid5f` to reflect that it is not a traditional
193RAID5 implementation - only full stripe writes are supported, partial stripe
194writes (read-modify-write) are not.
195
196### rpc
197
198Added `psk` parameter to `bdev_nvme_attach_controller` RPC in order to enable SSL socket implementation
199of TCP connection and set the PSK. Applicable for TCP transport only.
200
201New options `enable_ktls` and `tls_version` were added to the `sock_impl_set_options` structure.
202New options `psk_key` and `psk_identity` were added to the `sock_impl_set_options` structure.
203
204Added warning message for `bdev_rbd_create`, if it is used without -c.
205`bdev_rbd_create()` API without specifying -c is deprecated and will be removed in future release.
206
207Renamed `enable_vmd` RPC to `vmd_enable` to make it consistent with our naming scheme of
208`<subsystem>_<action>`.  For now, the old name is still available, but is marked as deprecated.
209
210New function `spdk_rpc_get_method_state_mask` was added to RPC library.
211
212### sma
213
214Extended `VolumeParameters` with crypto parameters allowing the user to configure crypto when
215attaching a volume to a device.  This interface is now supported by all upstream device types
216(nvmf-tcp, virtio-blk, vfio-user) using `bdev_crypto`.  Users must specify the crypto engine to use
217under `crypto` section in config.  It is also possible to register out-of-tree crypto engines by
218inheriting from the `CryptoEngine` class.
219
220Added two new methods: `SetQos` and `GetQosCapabilities` allowing the user to configure QoS on a
221per-device or per-volume level.  Not all QoS settings have to be supported by each device, so users
222can use `GetQosCapabilities` to query them for that.  All upstream device types support QoS on a
223per-volume level using bdev layer's QoS mechanism.
224
225### sock
226
227Added new `ssl` based socket implementation, the code is located in `module/sock/posix`.
228For now we are using hard-coded PSK and only support TLS 1.3.
229
230### util
231
232Added new functions: `spdk_hexlify` and `spdk_unhexlify`.
233
234A new API `spdk_xor_gen` was added to generate XOR from multiple source buffers. It is going to be
235used by `raid5f` for calculating parity.
236
237### vfu_tgt
238
239Added vfu_tgt library abstraction based on libvfio-user for PCI device emulation.
240Besides the NVMe device emulation, its now possible to emulate virtio-blk and virtio-scsi
241devices.
242
243### virtio
244
245virtio-vhost-user no longer tries to support dynamic memory allocation.  The vhost target does
246not support the high rate of SET_MEM_TABLE vhost messages that result from dynamic memory
247allocation, so a virtio-vhost-user device will now present an ERRLOG, assert, and skip the
248SET_MEM_TABLE vhost message if a memory notification is received outside of the normal device
249start/stop. Applications using the virtio library in vhost-user mode should now pre-allocate
250the application's memory using the -s/--mem-size option and use single shared memory file
251segments using the -g/--single-file-segments option.
252
253Added `vfio-user` transport type for virtio-blk and virtio-scsi devices.
254
255### vmd
256
257Fixed hotplug when a device is inserted in a slot in which a disk was already enumerated previously.
258Added two new RPCs: `vmd_remove_device` simulating a hotremove, and `vmd_rescan`, which rescans all
259buses managed by the VMD driver and hotplugs all newfound devices.
260
261## v22.05
262
263### sock
264
265A new option `ack_timeout` was added to the `spdk_sock_opts` structure.
266
267### util
268
269A new parameter `bounce_iovcnt` was added to `spdk_dif_generate_copy` and `spdk_dif_verify_copy`.
270The `bounce_iovcnt` is used to specify the number of bounce_iov to support multiple block-aligned
271fragment copies.
272
273A new API `spdk_copy_iovs_to_buf` and `spdk_copy_buf_to_iovs` were added to copy iovs to buf or
274copy buf to iovs. There're many cases need to use these two APIs.
275
276### bdev
277
278Removed deprecated spdk_bdev_module_finish_done(). Use spdk_bdev_module_fini_done() instead.
279
280A new API `spdk_bdev_unregister_by_name` was added to handle race conditions correctly.
281
282New APIs, `spdk_for_each_bdev` and `spdk_for_each_bdev_leaf`, were added to provide iteration
283safe for race conditions.
284
285A new RPC `bdev_nvme_get_io_paths` was added to get all active I/O paths.
286
287A new RPC `bdev_nvme_set_preferred_path` was added to set preferred I/O path for an NVMe bdev
288when in multipath mode. This RPC does not support NVMe bdevs in failover mode.
289
290A new RPC `bdev_nvme_set_multipath_policy` was added to set multipath policy of a NVMe bdev
291in multipath mode.
292
293A new option `disable_auto_failback` was added to the `bdev_nvme_set_options` RPC to disable
294automatic failback.
295
296### idxd / dsa
297
298A new parameter `flags` was added to all low level submission and preparation
299APIs to enable the caller to pass operation flags per the DSA specification.
300
301A new flag 'SPDK_IDXD_FLAG_PERSISTENT' was added to let DSA know that
302the destination is persistent.
303
304The RPC `idxd_scan_accel_engine` has been renamed to `dsa_scan_accel_engine`
305
306The RPC `iaa_scan_accel_engine` has been added.
307
308Many HW related structs/functions with the name `idxd` have been renamed `dsa`
309to more accurately represent the HW they are associated with.
310
311Two new functions were added to the library `spdk_idxd_submit_compress` and
312`spdk_idxd_submit_decompress`
313
314### accel_fw
315
316A new parameter `flags` was added to accel API.
317The APIs include:
318`spdk_accel_submit_copy`
319`spdk_accel_submit_dualcast`
320`spdk_accel_submit_fill`
321`spdk_accel_submit_copy_crc32c`
322`spdk_accel_submit_copy_crc32cv`
323`spdk_accel_submit_compress`
324`spdk_accel_submit_decompress`
325
326A new flag `ACCEL_FLAG_PERSISTENT` was added to indicate the target memory is PMEM.
327
328The API `spdk_accel_get_capabilities` has been removed.
329
330### crypto
331
332Support for AES_XTS was added for MLX5 polled mode driver (pmd).
333
334bdev_crypto_create RPC now requires hexlified 'key' and 'key2' params for all pmd drivers.
335Unhexlifying is performed during RPC command processing and the vbdev crypto module runs on
336binary keys as before.
337
338### bdev
339
340Added a timeout option to the `bdev_get_bdevs` RPC.  It allows the user to specify the amount of
341time to wait until a bdev with a given name appears in the system.
342
343### bdev_nvme
344
345Added `bdev_nvme_add_error_injection` and `bdev_nvme_remove_error_injection` RPCs to add and
346remove NVMe error injections.
347
348New parameters, `ctrlr_loss_timeout_sec`, `reconnect_delay_sec`, and `fast_io_fail_timeout_sec`, are
349added to the RPC `bdev_nvme_set_options`. They can be overridden if they are given by the RPC
350`bdev_nvme_attach_controller`.
351
352### blobstore
353
354New functions `spdk_blob_io_writev_ext` and `spdk_blob_io_readv_ext` are added. The new functions accept
355`spdk_blob_ext_io_opts` structure with extended IO request options.
356
357### event
358
359Added `msg_mempool_size` parameter to `spdk_reactors_init` and `spdk_thread_lib_init_ext`.
360The size of `g_spdk_msg_mempool` can now be controlled through the same-named
361user option of `spdk_app_opts` structure.
362
363### nvme
364
365The API `spdk_nvme_ctrlr_prepare_for_reset()` was deprecated. The functionality provided by the
366`spdk_nvme_ctrlr_prepare_for_reset()` was merged into the API `spdk_nvme_ctrlr_disconnect()`.
367
368### nvmf
369
370Removed deprecated max_qpairs_per_ctrlr parameter from nvmf_create_transport RPC. Use
371max_io_qpairs_per_ctrlr instead.
372
373Deprecated the ability for hosts to connect to the discovery subsystem automatically on any
374existing listener. Users should now explicitly add listeners for the discovery subsystem.
375Host can still connect to the discovery subsystem as before, but a warning message will be
376emitted if no listener was configured for the transport ID of the incoming connection.
377
378Added adaptive interrupt feature for vfio-user transport. New parameter `disable_adaptive_irq`
379is added to the RPC `nvmf_create_transport`.
380
381### thread
382
383Added `spdk_thread_exec_msg()` API.
384
385### scheduler
386
387`framework_set_scheduler` can now be called after application initialization.
388Added callbacks to set custom parameters specific for each scheduler implementation
389and `framework_get_scheduler` to retrieve them.
390
391Added `dynamic` scheduler options: load_limit, core_limit, core_busy. Their descriptions
392are available in JSON-RPC document, in section
393[framework_set_scheduler](jsonrpc.html#rpc_framework_set_scheduler).
394
395### raid
396
397Add concat as a special raid module. The concat module could create a virtual bdev.  The
398virtual bdev combines multiple underlying bdevs together. The layout of the underlying
399bdevs is one after another. The concat bdev is extendable. When the free space of the
400concat bdev is not enough, the user can deconstruct the concat bdev, then reconstruct it
401with an additional underlying bdev.
402
403### sock
404
405Allow MSG_ZEROCOPY flag to be set or not according to data size, which can be enabled and
406set by setting "zerocopy_threshold". zerocopy_threshold = 0 means disable this function;
407zerocopy_threshold > 0 means enable it and use this value as the threshold.
408
409### rpc
410
411Introduced `zerocopy_threshold` to enable zerocopy on send for server sockets according to
412data size to be flushed.
413
414## v22.01
415
416### accel
417
418The batching capability was removed. Batching is now considered an implementation
419detail of the low level drivers.
420
421### bdev
422
423The NVMe bdev module supports multipath and improved I/O error resiliency.
424
425The parameter `retry_count` of the RPC `bdev_nvme_set_options` was deprecated and will be
426removed in SPDK 22.04, and the parameter `transport_retry_count` is added and used instead.
427
428An new parameter `bdev_retry_count` is added to the RPC `bdev_nvme_set_options`.
429
430New parameters, `ctrlr_loss_timeout_sec`, `reconnect_delay_sec`, and `fast_io_fail_timeout_sec`, are
431added to the RPC `bdev_nvme_attach_controller`.
432
433An new parameter `num_io_queues` is added to `bdev_nvme_attach_controller` RPC to allow specifying amount
434of requested IO queues.
435
436Added `key_file` parameter to the `rbd_register_cluster` RPC.  It is an optional parameter to
437specify a keyring file to connect to a RADOS cluster.
438
439Added `spdk_bdev_get_zone_id` API to retrieve zone_id for a certain LBA.
440
441### bdev_aio
442
443Added `bdev_aio_rescan` RPC to allow rescanning the size of aio bdev.
444
445### bdev_nvme
446
447Added discovery service to bdev_nvme module, which now can connect to a discovery controller.
448bdev_nvme will connect to all current and future subsystems in the discovery controller.
449Added `bdev_nvme_start_discovery` and `bdev_nvme_stop_discovery` RPC.
450
451### dpdk
452
453Updated DPDK submodule to DPDK 21.11.
454
455### env
456
457Added `spdk_pci_for_each_device`.
458
459Removed `spdk_pci_get_first_device` and `spdk_pci_get_next_device`.  These APIs were unsafe, because
460they did not account for PCI devices being inserted or removed while the caller was using handles
461returned from these APIs.  Existing users of these APIs should switch to `spdk_pci_for_each_device`
462instead.
463
464Added 3 experimental APIs to handle PCI device interrupts (`spdk_pci_device_enable_interrupt`,
465`spdk_pci_device_disable_interrupt`, `spdk_pci_device_get_interrupt_efd`).
466
467Added `framework_get_pci_devices` RPC to list PCIe devices attached to an SPDK application.
468
469### idxd
470
471Many APIs are now vectored rather than scalar, meaning they take iovecs instead of individual pointers.
472
473### json
474
475Added `spdk_json_write_bytearray` API to serialize a buffer as a hex string.
476
477### nvme
478
479API `spdk_nvme_trtype_is_fabrics` was added to return existing transport type
480is fabric or not.
481
482API `spdk_nvme_poll_group_remove` was limited to be available only for a
483disconnected qpair in the group.
484
485New APIs, `spdk_nvme_ctrlr_disconnect`, `spdk_nvme_ctrlr_reconnect_async`, and
486`spdk_nvme_ctrlr_reconnect_poll_async`, have been added to improve error recovery, and
487the existing APIs,`spdk_nvme_ctrlr_reset_async` and `spdk_nvme_ctrlr_reset_poll_async`
488were deprecated.
489
490Added `spdk_nvme_ctrlr_get_discovery_log_page` API for getting the full discovery log page
491from a discovery controller.
492
493### nvmf
494
495Added support for zero-copy operations in the NVMe-oF TCP target. It can be enabled via
496the `zcopy` parameter when creating a transport. The zero-copy operations are only used
497for requests not using in-capsule data.
498
499Added a `subsystem` parameter to `spdk_nvmf_transport_stop_listen_async`. When not NULL,
500it will only disconnect qpairs for controllers associated with the specified subsystem.
501
502Removed accept poller from transport layer. Each transport can have its own policy of
503handling new connections. To notify transport layer `spdk_nvmf_poll_group_add` and
504`spdk_nvmf_tgt_new_qpair` can be used.
505
506### scsi
507
508Structure `spdk_scsi_lun` has been extended with new member `resizing` so that SCSI layer now reports
509unit attention for disk resize.
510
511### trace
512
513Added `spdk_trace_create_tpoint_group_mask` to return tracepoint group mask from
514a tracepoint group name.
515
516Added `trace_set_tpoint_mask` and `trace_clear_tpoint_mask` RPC to allow enabling
517individual traces.
518
519### util
520
521Added `spdk_ioviter_first` and `spdk_ioviter_next` to iterate over two iovecs and
522yield pointers to common length segments.
523
524### sock
525
526A new parameter `hint` is added to `spdk_sock_get_optimal_sock_group`. It allows to suggest
527a poll group when no optimal poll group is found.
528
529## v21.10
530
531Structure `spdk_nvmf_target_opts` has been extended with new member `discovery_filter` which allows to specify
532filtering rules applied during discovery log generation. Refer to `enum spdk_nvmf_tgt_discovery_filter` for more info.
533
534### bdev
535
536New API `spdk_bdev_get_memory_domains` has been added, it allows to get SPDK memory domains used by bdev.
537
538New API functions `spdk_bdev_readv_blocks_ext` and `spdk_bdev_writev_blocks_ext` have been added.
539These functions accept `spdk_bdev_ext_io_opts` structure with extended IO request
540options, e.g. DMA memory domain which describes data that may belong to another memory domain and
541can't be accessed directly.
542
543Added `async_fini_start` to allow bdev modules to complete the `fini_start` asynchronously,
544with new `spdk_bdev_module_fini_start_done` API.
545
546Deprecated `spdk_bdev_module_finish_done()` API, which will be removed in SPDK 22.01.
547Bdev modules should use `spdk_bdev_module_fini_done()` instead.
548
549The `ocssd` bdev has been removed. The Open Channel specification has been largely superseded by
550zoned namespaces, few if any devices have been brought to market, and there is little reason to
551continue to support this. OCSSD support in the nvme driver will remain for now.
552
553### dma
554
555A new library, lib/dma, has been added. This library provides the necessary infrastructure for
556handling systems and devices with multiple memory domains. For example, a PCIe add-in card with an
557SoC may be running SPDK on the SoC. That SoC has its own local memory, but SPDK may be controlling
558devices that can also access the host system memory. This library provides infrastructure to enumerate
559the memory domains and request hardware perform DMA transfers between them.
560
561### dpdk
562
563Updated DPDK submodule to DPDK 21.08.
564
565### event
566
567Added the `disable_signal_handlers` flag to the `spdk_app_opts` struct.
568
569### idxd
570
571Added `spdk_idxd_get_socket` to query the socket that the idxd device
572is on.
573
574### json
575
576Added API to allow for writing and decoding of new types:
577
578- `spdk_json_write_named_uint16`
579- `spdk_json_write_named_uint8`
580- `spdk_json_write_uint16`
581- `spdk_json_write_uint8`
582- `spdk_json_number_to_uint8`
583- `spdk_json_decode_uint8`
584
585### log
586
587Added API `spdk_log_to_syslog_level` to return syslog level based on SPDK's
588log level.
589
590### nvme
591
592Added new functions `spdk_nvme_zns_set_zone_desc_ext` and `spdk_nvme_zns_ext_report_zones`
593to set zone descriptor extension and to get extended zone report respectively.
594
595New API `spdk_nvme_ctrlr_get_memory_domains` has been added, it allows to get SPDK memory domains used by nvme controller.
596
597New API functions `spdk_nvme_ns_cmd_readv_ext` and `spdk_nvme_ns_cmd_writev_ext`
598have been added. These functions accept `spdk_nvme_ns_cmd_ext_io_opts` structure with extended IO request
599options, e.g. DMA memory domain which describes data that may belong to another memory domain and
600can't be accessed directly.
601
602Added a new function `spdk_nvme_ctrlr_get_regs_bpinfo` to get boot partition info of a controller.
603Added new functions `spdk_nvme_ctrlr_write_boot_partition`,
604`spdk_nvme_ctrlr_read_boot_partition_start` and `spdk_nvme_ctrlr_read_boot_partition_poll`
605to write and read the boot partitions of a controller.
606
607Added `spdk_nvme_ctrlr_get_opts` to retrieve the current controller options.
608
609Added `async_mode` to `spdk_nvme_io_qpair_opts` to enable creation of submission and completion
610queues asynchronously. This mode is currently supported at PCIe layer,
611which tracks the qpair creation with state machine and returns to the user immediately.
612Default mode is set to false to create io qpairs synchronously.
613
614Added `spdk_nvme_ctrlr_get_regs_cc` to retrieve NVMe controller CC (Configuration) register.
615
616Added `spdk_nvme_ctrlr_prepare_for_reset` to inform the driver that the application is preparing
617to reset the specified NVMe controller. This function allows the driver to make decisions
618knowing that a reset is about to happen.
619
620### nvmf
621
622Added `oncs` to `struct spdk_nvmf_ctrlr_data` so that the transport layer
623can decide support RESERVATION feature or not.
624
625An `opts_size` element was added in the `spdk_nvmf_ns_opts` structure to solve the
626ABI compatibility issue between different SPDK version. An new option `anagrpid` was
627added in the `spdk_nvmf_ns_opts` structure.
628
629An new parameter `anagrpid` was added to the RPC `nvmf_subsystem_add_ns`.
630
631An new parameter `anagrpid` was added to the RPC `nvmf_subsystem_listener_set_ana_state`.
632
633`spdk_nvmf_subsystem_destroy` is now can be asynchronous, it accepts a callback and callback argument.
634
635A new parameter, `poll_groups_mask` was added to the `nvmf_set_config` RPC that allows specifying
636a subset of cores for the nvmf poll groups. This helps to avoid imbalances when some cores are
637busy with periodic timer tasks that run very frequently.
638
639A new parameter, `commit` was added to `nvmf_bdev_ctrlr_end_zcopy` that allows indicating whether
640the buffers should be committed.
641
642Added `listen_dump_opts` to `spdk_nvmf_transport_ops` so that the transport layer can display
643listen opts.
644
645Added `fabrics_connect_timeout_us` to `bdev_nvme_attach_controller` RPC to allow specifying
646timeout for connect operation.
647
648Added `multipath` to `bdev_nvme_attach_controller` RPC to allow specifying multipath behavior.
649
650### scheduler
651
652New API for implementing schedulers and governors. Please see `include/spdk/scheduler.h` for details.
653
654### scsi
655
656New functions, `spdk_scsi_dev_get_first_lun` and `spdk_scsi_dev_get_next_lun`
657have been added to iterate LUNs of a SCSI device.
658
659Each SCSI device supports 256 LUNs at the maximum now and the macro constant
660`SPDK_SCSI_DEV_MAX_LUN` was removed.
661
662### trace_parser
663
664A new library, lib/trace_parser, has been added. This library provides functions that parse traces
665recorded by an SPDK application. That includes merging traces from multiple cores,
666sorting them by their timestamp and constructing trace entries spanning across multiple buffers.
667
668### util
669
670The `spdk_fd_group_add` API now takes a `name` parameter.
671
672## v21.07
673
674### accel_fw
675
676Added API `spdk_accel_submit_copy_crc32c` to perform a CRC32C while copying data.
677
678Added API `spdk_accel_batch_prep_copy_crc32c` to batch CRC32C + copy commands.
679
680Added API `spdk_accel_submit_copy_crc32cv` to submit chained CRC32C + copy commands.
681
682### bdev
683
684Change `spdk_bdev_read_blocks_with_md` arg offset definition from int64_t to uint64_t.
685
686Red-black tree has been used to organize the bdev names and aliases uniformly
687to provide faster lookup.
688
689Removed ZCOPY emulation: The bdev module can be checked to see if it supports ZCOPY
690and if not supported then use existing READ/WRITE commands.
691
692Added iov to spdk_bdev_zcopy_start.
693
694### dpdk
695
696Updated DPDK submodule to DPDK 21.05.
697
698### idxd
699
700Remove the `probe_cb` parameter in `spdk_idxd_probe` function. And remove the definition
701of `spdk_idxd_probe_cb` function pointer. It should be implemented in idxd_user.c.
702
703Added API `spdk_idxd_submit_copy_crc32c` to perform a CRC32C while copying data.
704
705Added API `spdk_idxd_batch_prep_copy_crc32c` to prepare a batch operation to perform
706a CRC32C while copying data.
707
708We have userspace idxd driver under accel_engine library (module/accel/idxd/accel_engine).
709And kernel idxd driver usage is also added under the accel_engine library. This approach
710implemented a wrapper library to use IDXD device by leveraging the kernel DSA driver in
711SPDK idxd library (lib/idxd). Then users can leverage the RPC later to configure how to
712use the DSA device by user space driver or kernel driver.
713
714### init
715
716Added new `init` library that initializes the SPDK subsystems, which previously was
717internal to application framework. That functionality has been made public and for
718use by applications which don't leverage SPDK's application framework.
719
720### iscsi
721
722New parameters, `pdu_pool_size`, `immediate_data_pool_size`, and `data_out_pool_size`,
723were added to the RPC `iscsi_set_options` to run iSCSI target with varying amount of
724available memory.
725
726### json
727
728Added API `spdk_json_write_named_uint128` and `spdk_json_write_uint128` to perform
729the uint128 related data.
730
731### net
732
733Removed deprecated `net` library.
734
735Added support for ZCOPY.  ZCOPY is used in preference to READ and WRITE if the
736bdev module supports ZCOPY and the bdev module has ZCOPY enabled.
737
738### nvme
739
740`spdk_nvme_map_prps` and `spdk_nvme_map_cmd` were moved to nvmf/vfio-user as internal APIs
741as vfio-user is the only user for the above two APIs.
742
743Added a new function `spdk_nvme_ns_cmd_copy` to submit a Simple Copy Command to a Namespace.
744
745Update the `spdk_nvme_generic_command_status_code` structure with new status code
746according to the definition in NVMe 1.4 spec.
747
748`spdk_nvme_ctrlr_get_default_ctrlr_opts` now sets `use_cmb_sqs` to false. This means
749that if a controller has a CMB and supports SQs in the CMB, SPDK will not use
750the CMB for SQs by default - the user must set `use_cmb_sqs` to true in
751the `spdk_nvme_ctrlr_opts` structure prior to controller attach.
752
753Add a new function `spdk_nvme_detach_poll` to simplify a common use case to continue
754polling until all detachments complete.
755
756Added new argument `timeout_admin_us` to `spdk_nvme_ctrlr_register_timeout_callback` so callers
757can specify a different timeout for admin commands vs. io commands.
758
759An existing function `spdk_nvme_detach_async` was updated to add one or more detachments
760to an active context while it is being polled.
761
762Rename a variable in the member `cmic` of the struct `spdk_nvme_ctrlr_data` from
763`multi_host` to `multi_ctrlr`. The variable means that the NVM subsystem may have two or
764more controllers if set to 1. However `multi_host` had indicated a particular use case
765such that the NVM subsystem is used by multiple hosts.
766
767A new option `disable_read_ana_log_page` was added to struct `spdk_nvme_ctrlr_opts` to disable
768reading ANA log page. The upper layer is expected to read ANA log page instead if `true`.
769The default value is `false`.
770
771New APIs, `spdk_nvme_ctrlr_reset_async` and `spdk_nvme_ctrlr_reset_poll_async`, have been added to
772reset a controller asynchronously.
773
774New RPC `bdev_nvme_reset_controller` was added, to reset an NVMe controller.
775
776Added `spdk_nvme_ns_get_nguid` function to get NGUID for the given namespace.
777
778Added `spdk_nvme_ctrlr_is_fabrics` function to indicate whether a ctrlr handle
779is associated with a fabrics controller.
780
781### nvmf
782
783Added `min_cntlid` and `max_cntlid` to `nvmf_create_subsystem` to limit the controller ID range.
784Added `spdk_nvmf_subsystem_get_min_cntlid` and `spdk_nvmf_subsystem_get_max_cntlid` to request those values.
785
786`spdk_nvmf_request_get_buffers_multi` API is removed.
787
788Added the `nvmf_set_crdt` RPC for setting command retry delay times.
789
790Expanded `spdk_nvmf_poll_group_stat` with current qpair count statistics.
791
792Removed following deprecated APIs:
793
794- `spdk_nvmf_poll_group_get_stat` (function in `nvmf.h`),
795- `spdk_nvmf_transport_poll_group_get_stat` (function in `nvmf.h`),
796- `spdk_nvmf_transport_poll_group_free_stat`(function in `nvmf.h`),
797- `spdk_nvmf_rdma_device_stat` (struct in `nvmf.h`),
798- `spdk_nvmf_transport_poll_group_stat` (struct in `nvmf.h`),
799- `poll_group_get_stat` (transport op in `nvmf_transport.h`),
800- `poll_group_free_stat` (transport op in `nvmf_transport.h`).
801
802### rpc
803
804New RPC `bdev_rbd_register_cluster` and `bdev_rbd_unregister_cluster` was added, it allows to create
805and delete the rados object cluster, then users can choose the cluster to create related rbd
806device.
807
808Revised `bdev_rbd_create` parameter, it allows to use an optional parameter `--cluster-name`
809to create a rbd bdev with  an already registered Rados Cluster Object.
810
811New RPC `bdev_rbd_get_clusters_info` was added, it allows to get the info of the registered
812Rados Cluster names.
813
814New optional parameter, `timeout_admin_us`, added to the bdev_nvme_set_options RPC.
815
816Revised a parameter `--stripe-size_kb` to `--stripe-size-kb` of `bdev_raid_create` method
817provided in `scripts/rpc.py` for consistency.
818
819An new optional parameter `config_kernel_mode` was added to the RPC `idxd_scan_accel_engine`,
820and this is used to enable using the kernel mode IDXD driver.
821
822Removed deprecated parameter `enable-zerocopy-send` of RPC `sock_impl_set_options`,
823use `enable-zerocopy-send-server` or `enable-zerocopy-send-client` instead.
824Removed deprecated parameter `disable-zerocopy-send` of RPC `sock_impl_set_options`,
825use `disable-zerocopy-send-server` or `disable-zerocopy-send-client` instead.
826
827### rpm
828
829Removed deprecated `pkg/spdk.spec`, please use `rpmbuild/spdk.spec` instead.
830See [RPM documentation](https://spdk.io/doc/rpm.html) for more details.
831
832### thread
833
834Red-black tree has been used for timed pollers to provide faster insertion and deletion
835and for io_devices to provide faster lookup.
836
837Removed `spdk_io_channel` structure from public header and moved it to thread_internal.h.
838
839### trace
840
841Added `spdk_trace_register_description_ext` function to register variable number of tracepoint arguments.
842
843Added ability to chain multiple trace entries together to extend the size of the argument buffer.
844
845### util
846
847Red-black tree macros has been added by using the macros provided by the FreeBSD operating system
848under the same BSD license.
849
850Add an new macro `SPDK_SIZEOF_MEMBER` to get the size of a member of a struct.
851
852`spdk_crc32c_iov_update` function was added to support calculating the crc32c of the iovs.
853
854Added zipf random number generator with power law probability distribution.
855When applied to performance testing of block devices, it will select blocks over
856the full range of LBAs, but will more frequently select lower-numbered LBAs.
857
858## v21.04
859
860### accel
861
862Two new accelerated crc32 functions `spdk_accel_submit_crc32cv` and
863`spdk_accel_batch_prep_crc32cv` are added in order to provide the
864chained accelerated CRC32 computation support.
865
866### bdev
867
868For `bdev_ocssd_create` RPC, the optional parameter `range` was removed.
869Only one OCSSD bdev can be created for one OCSSD namespace.
870
871Removed the `spdk_bdev_open` from bdev library API.
872Removed the `spdk_vbdev_register` and `spdk_bdev_part_base_construct` from bdev module API.
873Removed the `config_text` function for bdev modules to report legacy config.
874
875Added `spdk_bdev_get_max_active_zones` API to display maximum number active zones of a given bdev.
876
877Added `spdk_bdev_get_max_zone_append_size` API to display maximum zone append data transfer size.
878
879### bdev_nvme
880
881Added support for zoned namespaces.
882
883### blobstore
884
885Removed the `spdk_bdev_create_bs_dev_from_desc` and `spdk_bdev_create_bs_dev` API.
886
887### env
888
889Added `spdk_pci_device_allow` API to allow applications to add PCI addresses to
890the allowed list after the application has started.
891
892Removed the `pci_whitelist`, `pci_blacklist` and `master_core` members of struct `spdk_env_opts`.
893
894Added hotplug support based on uevent in `pci_event.c`. Added usage of this functionality in
895nvme, virtio-scsi and virtio_blk libraries. Please see the new API `spdk_pci_event_listen`,
896`spdk_pci_get_event`, `spdk_pci_register_error_handler` and `spdk_pci_unregister_error_handler`.
897
898### event
899
900Removed the `config_file`, `max_delay_us`, `pci_whitelist`
901and `pci_blacklist` members of struct `spdk_app_opts`.
902
903### idxd
904
905A new API `spdk_idxd_device_needs_rebalance` was added so that users of the library
906can know whether they need to rebalance the flow control for the channel
907that was just added/removed.  This is based on how the low level library
908shares devices amongst channels.
909
910The API `spdk_idxd_reconfigure_chan` had the `num_channels` removed as this
911is now tracked in the library.  The app makes use the new API above to
912determine whether to rebalance or not. This applies to `spdk_idxd_configure_chan`
913as well.
914
915The API `spdk_idxd_put_channel` now returns the rebalance state for the
916underlying device.
917
918### iscsi
919
920A security vulnerability has been identified and fixed in the SPDK iSCSI target.
921A TEXT PDU with no data, but CONTINUE flag set, would result in a NULL pointer dereference
922and crash the SPDK iSCSI target process. All users of the SPDK iSCSI target
923are recommended to update. All SPDK versions <= v21.01 are affected.
924
925### net
926
927The net library is deprecated and will be removed in the 21.07 release.
928
929### nvme
930
931Added a new function `spdk_nvme_ctrlr_get_regs_pmrcap` to get the PMR capabilities.
932
933Added an accelerated table pointer in `spdk_nvme_poll_group`
934which can be used to provide the accelerated functions by users with
935hardware engine, such as crc32c accelerated function.
936
937Added new functions `spdk_nvme_ctrlr_get_pmrsz`, `spdk_nvme_ctrlr_enable_pmr`,
938`spdk_nvme_ctrlr_disable_pmr`, `spdk_nvme_ctrlr_map_pmr` and `spdk_nvme_ctrlr_unmap_pmr`.
939
940Added NVMe transport operations to enable, disable, map and unmap the PMR.
941
942Added `spdk_nvme_qpair_get_optimal_poll_group` function and `qpair_get_optimal_poll_group`
943function pointer in spdk_nvmf_transport_ops structure in order to add the qpair to the most
944suitable polling group.
945
946Added OPTPERF and namespace optimal performance fields to nvme_spec.h.
947
948Added `spdk_nvme_set_hotplug_filter` API to allow applications to choose which
949hot-inserted SSDs should be probed. This is useful for use cases where multiple
950independent SPDK processes are running on one node. The filter function can
951then be implemented in these processes to decide which SSDs to probe based on
952the new SSD's PCI address.
953
954New functions `spdk_nvme_poll_group_get_stats` and `spdk_nvme_poll_group_free_stats`
955were added. These functions allow to get transport statistics per NVME poll group.
956
957Added `spdk_nvme_map_cmd` API to map the NVMe command with SGL cases.
958
959Added support for vector variant of ZNS zone append commands with new API
960`spdk_nvme_zns_zone_appendv` and `spdk_nvme_zns_zone_appendv_with_md`.
961
962Added `spdk_nvme_zns_ns_get_max_open_zones` and `spdk_nvme_zns_ns_get_max_active_zones` API,
963to display maximum number of open and active zones of the given namespace.
964
965Added `spdk_nvme_zns_ns_get_zone_size_sectors` API to provide size of zone in number of
966sectors.
967
968Added `spdk_nvme_qpair_get_id` API to display the ID of the specified qpair.
969
970### nvmf
971
972Removed the `spdk_nvmf_tgt_listen` and `spdk_nvmf_subsystem_add_ns` API.
973
974Added new APIs:
975
976- `spdk_nvmf_poll_group_dump_stat` (function in `nvmf.h`).
977- `poll_group_dump_stat` (transport op in `nvmf_transport.h`).
978
979The following APIs have been deprecated and will be removed in SPDK 21.07:
980
981- `spdk_nvmf_poll_group_get_stat` (function in `nvmf.h`),
982- `spdk_nvmf_transport_poll_group_get_stat` (function in `nvmf.h`),
983- `spdk_nvmf_transport_poll_group_free_stat`(function in `nvmf.h`),
984- `spdk_nvmf_rdma_device_stat` (struct in `nvmf.h`),
985- `spdk_nvmf_transport_poll_group_stat` (struct in `nvmf.h`),
986- `poll_group_get_stat` (transport op in `nvmf_transport.h`),
987- `poll_group_free_stat` (transport op in `nvmf_transport.h`).
988
989See header files for details.
990
991The `trtype` field in JSON returned by `nvmf_get_stats` RPC contains now the name of the transport,
992which is the same as the type for defined transports and more informative for a custom transport.
993
994Added `hdgst` and `ddgst` parameters to `bdev_nvme_attach_controller` RPC in order change
995state of TCP header and data digest.
996
997Added `num_cqe` parameter to `nvmf_create_transport` RPC to set number of completion queues (CQ)
998for RDMA transport. Useful when CQ resize operation is not supported, for example iWARP.
999
1000### ocf
1001
1002Updated OCF submodule to v20.12.2
1003
1004Added `bdev_ocf_set_cache_mode` RPC to dynamically switch cache mode of OCF bdev.
1005
1006### opal
1007
1008Removed the `spdk_opal_supported` API.
1009
1010### raid
1011
1012For `bdev_raid_create` RPC, the deprecated parameter `strip_size` was removed.
1013
1014### rpc
1015
1016New RPC `bdev_nvme_get_transport_statistics` was added, it allows to get transport statistics
1017of nvme poll groups.
1018
1019Parameter `enable-zerocopy-send` of RPC `sock_impl_set_options` is deprecated and will be removed in SPDK 21.07,
1020use `enable-zerocopy-send-server` or `enable-zerocopy-send-client` instead.
1021Parameter `disable-zerocopy-send` of RPC `sock_impl_set_options` is deprecated and will be removed in SPDK 21.07,
1022use `disable-zerocopy-send-server` or `disable-zerocopy-send-client` instead.
1023
1024Added cmd_parser.py used to parse the args from argparse. There are
1025two benefit to use command parser:
1026
1027- Simplify the definition of rpc method. It will reduce the rpc method code.
1028- Make the rpc call more versatile. User can add private args into rpc method.
1029
1030### rpm
1031
1032Added support for new RPM spec, rpmbuild/spdk.spec, which can be used for packaging the
1033SPDK. The pkg/spdk.spec is considered to be deprecated and scheduled for removal in SPDK 21.07.
1034See [RPM documentation](https://spdk.io/doc/rpm.html) for more details.
1035
1036### sock
1037
1038The type of `enable_placement_id` in struct `spdk_sock_impl_opts` is changed from
1039bool to int. We can use RPC to configure different value of `enable_placement_id`.
1040Then we can leverage SO_INCOMING_CPU to get placement_id, which aims to utilize
1041CPU cache locality, enabled by setting enable_placement_id=2.
1042
1043A new socket placement mode called PLACEMENT_MARK has been added. Some NICs allow
1044sockets to be marked using the SO_MARK socket option as a hint for which hardware
1045queue they should be associated with. This mode leverages that by setting the same
1046value for all sockets within a poll group.
1047
1048New parameters `enable_zerocopy_send_server` and `enable_zerocopy_send_client` were added
1049to struct spdk_sock_impl_opts, these parameters enable or disable zero copy send for server
1050and client sockets which are created using `spdk_sock_listen` and `spdk_sock_listen_ext` (server);
1051`spdk_sock_connect` and `spdk_sock_connect_ext` (client) functions. Existing parameter
1052`enable_zerocopy_send`  enables or disables zero copy send for both server and client sockets.
1053
1054### thread
1055
1056A new API `spdk_io_channel_get_io_device` was added to get the io_device for the specified
1057I/O channel.
1058
1059Added `spdk_thread_set_interrupt_mode` function in order to set present spdk_thread into
1060interrupt mode or back to poll mode. It is valid only when thread interrupt facility is
1061enabled by `spdk_interrupt_mode_enable`.
1062
1063Added `spdk_poller_register_interrupt` function to mark that the poller is capable of
1064entering interrupt mode. Callback function will be called when the poller must transition
1065into or out of interrupt mode.
1066
1067### virtio
1068
1069Added the `bdev_virtio_blk_set_hotplug` RPC for the virtio blk pci device.
1070
1071## v21.01
1072
1073### bdev
1074
1075An `opts_size` element was added in the `spdk_bdev_opts` structure to solve the
1076ABI compatibility issue between different SPDK version. And also add `opts_size`
1077parameter in spdk_bdev_get_opts function. Two fields `small_buf_pool_size` and
1078`large_buf_pool_size` were added into spdk_bdev_opts, which were used to determine
1079the small and large buffer pool size of the whole bdev module.
1080
1081A new API `spdk_bdev_wait_for_examine` was added to allow for checking state of
1082examine process. Along with corresponding `bdev_wait_for_examine` RPC, which
1083is now always called during `spdk_bdev_subsystem_config_json` making sure
1084every bdev is ready to be used.
1085
1086A new API `spdk_bdev_io_get_aio_status` was added for getting the status of
1087bdev_io as Linux AIO errno. Also `spdk_bdev_io_complete_aio_status` function
1088and `SPDK_BDEV_IO_STATUS_AIO_ERROR` were added for bdev module to complete
1089a bdev_io with Linux AIO errno.
1090
1091A new API `spdk_bdev_get_module_name` was added for getting block device module name.
1092Also `spdk_bdev_get_module_ctx` was added to obtain a bdev module context for
1093the block device opened by the specified descriptor.
1094
1095Added `max_segment_size` and `max_num_segments` to `spdk_bdev` structure for
1096bdev modules to specify splitting requirements.
1097
1098### blob
1099
1100An `opts_size` element was added in the `spdk_bs_opts` structure to solve the
1101ABI compatibility issue between different SPDK version. And also add `opts_size`
1102parameter in `spdk_bs_opts_init` function.
1103
1104An `opts_size` element was added in the `spdk_blob_opts` structure to solve the
1105ABI compatibility issue between different SPDK version. And also add `opts_size`
1106parameter in `spdk_blob_opts_init` function.
1107
1108An `opts_size` element was added in the `spdk_blob_open_opts` structure to solve the
1109ABI compatibility issue between different SPDK version. And also add `opts_size`
1110parameter in `spdk_blob_open_opts_init` function.
1111
1112### build
1113
1114SPDK now generates pkg-config files to simplify the process of determining which
1115libraries must be linked into an SPDK application.
1116
1117### dpdk
1118
1119Updated DPDK submodule to DPDK 20.11.
1120
1121Removed `--with-igb-uio-driver` configure option. Since DPDK 20.11 igb_uio driver
1122was moved to separate dpdk-kmods repository. If required, users need to refer to
1123dpdk-kmods repository to build the driver.
1124
1125### env
1126
1127The `pci_whitelist`, `pci_blacklist` and `master_core` members of struct `spdk_env_opts`
1128have been deprecated.  The new members are named `pci_allowed`, `pci_blocked` and
1129`main_core` respectively.
1130
1131An `opts_size` element was added in the `spdk_app_opts` structure
1132to solve the ABI compatibility issue between different SPDK version. An `opts_size`
1133parameter is added into `spdk_app_opts_init` function.
1134
1135### event
1136
1137The `pci_whitelist` and `pci_blacklist` members of struct `spdk_app_opts` have been
1138deprecated.  The new members are named `pci_allowed` and `pci_blocked` respectively.
1139
1140The `--pci-blacklist` command line option has been deprecated, replaced with
1141`--pci-blocked`.
1142
1143The `--pci-whitelist/-W` command line options have been deprecated, replaced with
1144`--pci-allowed/-A`.
1145
1146Added new experimental `dynamic` scheduler that rebalances idle threads, adjusts CPU frequency
1147using dpdk_governor and turns idle reactor cores to interrupt mode. Please see
1148[scheduler documentation](https://www.spdk.io/doc/scheduler.html) for details.
1149
1150## ioat
1151
1152The PCI BDF whitelist option has been removed from the `ioat_scan_accel_engine` RPC.
1153IOAT PCI functions can still be allowed or denied using SPDK application command
1154line options.
1155
1156### isa-l
1157
1158Updated ISA-L submodule to v2.30.0.
1159
1160### json
1161
1162A new API `spdk_jsonrpc_send_bool_response` was added to allow sending response for
1163writing json bool results into one function.
1164Update API `bdev_nvme_set_options` and add a `keep_alive_timeout_ms` parameter. Now you
1165can specify the `keep_alive_timeout` before creating NVMe bdev.
1166
1167### nbd
1168
1169Change the return type of function `spdk_nbd_stop` from void to int. And update the
1170`spdk_nbd_fini` with two parameters to make its behavior from sync to async.
1171
1172### nvme
1173
1174Directives support was added to the NVMe driver.
1175
1176Two async APIs `spdk_nvme_ctrlr_cmd_directive_receive` and `spdk_nvme_ctrlr_cmd_directive_send`
1177are added for Directive Send and Directive Receive command, respectively.
1178
1179Added a new function `spdk_nvme_ctrlr_reset_subsystem` to perform a NVMe
1180subsystem reset. Note: The NVMe-oF target does not support the subsystem reset yet.
1181
1182Add a new function `spdk_nvme_bytes_to_numd` to transfer bytes to number of
1183dwords.
1184
1185Added a new custom transport `SPDK_NVME_TRANSPORT_VFIOUSER` to enable NVMe
1186driver running with NVMe over vfio-user target.
1187
1188Added the vfio-user custom transport implementation in NVMe driver which can connect
1189to NVMe over vfio-user target via vfio-user transport.
1190
1191Added a new function `spdk_nvme_ctrlr_set_remove_cb` to remove or override
1192`remove_cb` and `remove_ctx` specified when the controller was probed.
1193
1194Added support for ZNS zone append command with new API `spdk_nvme_zns_zone_append` and
1195`spdk_nvme_zns_zone_append_with_md`.
1196
1197### nvmf
1198
1199`nvmf_fc_lld_fini` now takes callback and hence updating FC Broadcom LLD driver
1200to the latest is required.
1201
1202FC transport supported primary tagging and VMID.
1203
1204Broadcom FC LLD driver and SPDK NVMe-oF FC transport consolidated one LLD API,
1205`nvmf_fc_init_poller_queues` into another LLD API `nvmf_fc_init_q`.
1206Hence updating Broadcom FC LLD driver to the latest is required.
1207
1208The functions `destroy` and `qpair_fini` in the transport interface now accept a
1209`cb_fn` and `cb_arg` to call upon completion, and their execution can be asynchronous.
1210
1211The SPDK NVMe-oF target now supports async event notification for discovery log changes.
1212This allows the initiator to create persistent connection to discovery controller and
1213be notified of any discovery log changes.
1214
1215An `opts_size` element was added in the `spdk_nvmf_transport_opts` structure
1216to solve the ABI compatibility issue between different SPDK version. And also add
1217`opts_size` parameter in `spdk_nvmf_transport_opts_init` function.
1218
1219Added a new custom vfio-user transport implementation in NVMe-oF which can provide
1220emulated NVMe devices to QEMU and SPDK NVMe driver.
1221
1222Added new API `spdk_nvmf_tgt_listen_ext` that uses `spdk_nvmf_listen_opts` to allow
1223passing generic options to specific transport. This functionality replaces one provided
1224with `nvmf_subsystem_set_options`. Also removed `nvmf_subsystem_set_options` RPC
1225that allowed transport specific options within subsystem.
1226
1227The `trsvcid` in `nvmf_subsystem_add_listener` RPC is now optional.
1228
1229Pausing a subsystem now only pauses all admin queues. This allows for the
1230management of hosts and listeners, plus the addition of namespaces without a
1231full subsystem pause. Additionally, the target now allows for pausing
1232individual namespaces within a subsystem. To remove a namespace from a
1233subsystem, only the specific namespace must be paused. I/O will continue to
1234other namespaces while these operations execute.
1235
1236### rpc
1237
1238An new optional parameter `wait` was added to the RPC `iscsi_create_portal_group`,
1239and an new RPC `iscsi_start_portal_group` was added. They will be used not to start
1240listening on portals for a portal group until all associated target nodes are created
1241at startup, otherwise some iSCSI initiators may fail to re-login when SPDK iSCSI
1242target application restarts.
1243
1244Two optional parameter `--small-buf-pool-size` and `--large-buf-pool-size` were added
1245into `bdev_set_options` function.
1246
1247### vhost
1248
1249Added optional `packed_ring_recovery` parameter to `vhost_create_blk_controller` RPC
1250enabling packed ring live recovery.
1251
1252## v20.10
1253
1254### accel
1255
1256New APIs `spdk_accel_batch_cancel` and `spdk_idxd_batch_cancel` were added to allow
1257cancelling a batch sequence.
1258
1259### bdev
1260
1261A new `spdk_bdev_part_base_construct_ext` function has been added and the
1262`spdk_bdev_part_base_construct` has been deprecated.  The
1263`spdk_bdev_part_base_construct_ext` function takes bdev name as an argument instead
1264of bdev structure to avoid a race condition that can happen when the bdev is being
1265removed between a call to get its structure based on a name and actually opening it.
1266
1267Removed `spdk_bdev_config_text` function for bdev modules to report legacy config.
1268
1269### blobstore
1270
1271A new `spdk_bdev_create_bs_dev_ext` function has been added and `spdk_bdev_create_bs_dev_from_desc`
1272function has been deprecated.
1273
1274### dpdk
1275
1276Updated DPDK submodule to DPDK 20.08.
1277
1278### env
1279
1280A new API `spdk_mem_get_fd_and_offset` was added to get file descriptor and offset for
1281a given virtual address.
1282
1283### event
1284
1285Removed `spdk_subsystem_config` callback for submodules as part of legacy config removal.
1286
1287Removed `spdk_app_get_running_config` function that printed configuration in legacy format,
1288and removed `usr1_handler` from `struct spdk_app_opts` callback that was used to call it.
1289
1290Added SPDK thread scheduler framework which is used to rebalance load among CPU cores.
1291The scheduler implementation is pluggable and two schedulers are added first, `static` scheduler
1292and `gscheduler` scheduler.
1293
1294`static` scheduler is used by default and does not reschedule threads and keeps the initial
1295assignments.
1296
1297CPU frequency governor framework and implementation are also added.
1298`dpdk_governor` is the first implementation and is based on rte_power library of DPDK.
1299`gscheduler` scheduler utilizes the CPU frequency governor.
1300
1301Scheduler and governor frameworks are experimental features.
1302
1303### fio
1304
1305Bdev fio_plugin no longer supports legacy configuration files. Options `spdk_conf` and
1306`spdk_json_conf` have to point to valid JSON configuration.
1307
1308### gpt
1309
1310Removed option to disable GPT probing via legacy configuration. Please use generic
1311bdev functionality to replicate the behavior. See `bdev_set_options --disable-auto-examine`
1312and `bdev_examine` RPC.
1313
1314### intel-ipsec-mb
1315
1316Updated intel-ipsec-mb submodule to v0.54
1317
1318### isa-l
1319
1320Updated ISA-L submodule to v2.29.0.
1321
1322### iscsi
1323
1324The iSCSI target supports iSCSI login redirection feature to achieve fault tolerance
1325and load balancing particularly in scale out iSCSI target system, which runs multiple
1326SPDK iSCSI targets.
1327
1328### json
1329
1330A new API `spdk_json_decode_object_relaxed` was added to allow parsing json values
1331even if decoder for a given key is not found.
1332
1333A new API `spdk_json_free_object` was added to free memory allocated by `spdk_json_decode_object`.
1334
1335### log
1336
1337A log flag structure, `spdk_log_register_flag`, `spdk_log_get_first_flag`,
1338`spdk_log_get_next_flag` and macro `SPDK_LOG_REGISTER_COMPONENT`, have been added which
1339enable registering and interacting with log flags. Added `SPDK_INFOLOG`, `SPDK_DEBUGLOG`
1340and `SPDK_LOGDUMP` macros to display logs for specified log flag.
1341
1342The log flags in the event framework `-L` and several SPDK applications has been enabled on
1343release builds of SPDK. On debug builds this option will additionally set
1344log print level to `SPDK_LOG_DEBUG`.
1345
1346A new API `spdk_log_enable_timestamps` and new RPC `log_enable_timestamps` was added to
1347toggle log timestamps.
1348
1349### miscellaneous
1350
1351The contents of the log_rpc library have been moved to the event library. The log_rpc
1352library now no longer exists.
1353
1354The contents of the app_rpc library have been moved to the event library. The app_rpc
1355library now no longer exists.
1356
1357The contents of the bdev_rpc library have been moved to the bdev library. The app_rpc
1358library now no longer exists.
1359
1360The bdevperf application now disables the zcopy API by default. Prior to this change,
1361bdevperf enabled using the zcopy API by default which caused a performance impact of
1362up to 25% on bdevs that don't natively support zcopy because the API emulates zero-copy
1363by allocating a buffer. The bdevperf `-x` param was renamed to `-Z` and the default
1364value changed to false. For bdevs that support zcopy, use the -Z flag to enable
1365using zcopy API.
1366
1367### net
1368
1369Net framework intended for use by user-space TCP stacks was removed.
1370
1371### nvme
1372
1373Zoned Namespace Command Set support has been added to NVMe driver, see `nvme_zns.h` for details.
1374
1375New APIs, `spdk_nvme_detach_async` and `spdk_nvme_detach_poll_async`, have been added to
1376detach multiple controllers in parallel to mitigate lengthy shutdown notification of
1377a few NVMe SSDs.
1378
1379New APIs, `spdk_nvme_ns_get_ana_group_id` and `spdk_nvme_ns_get_ana_state`, have been
1380added to get ANA group ID and ANA state of the given namespace, respectively.
1381
1382If no specific command set is requested (by setting the command_set member in the
1383`spdk_nvme_ctrlr_opts` structure), SPDK will automatically select the most appropriate
1384command set based on what the controller supports.
1385
1386### nvmf
1387
1388A new API `spdk_nvmf_subsystem_add_ns_ext` has been added and the API `spdk_nvmf_subsystem_add_ns`
1389has been deprecated.
1390
1391The NVMe-oF target now supports Asymmetric Namespace Access (ANA) Reporting to provide
1392multipath to NVMe-oF initiator.
1393
1394Add `no_wr_batching` parameter to `spdk_nvmf_transport_opts` struct to disable
1395Work Requests batching in RDMA transport.
1396
1397NVMf Target transports can now parse any additional JSON params in the nvmf_create_transport RPC
1398through the JSON context provided via spdk_nvmf_target_opts->transport_specific.
1399
1400A new RPC `nvmf_subsystem_set_options` was added to allow transport specific options within subsystem.
1401
1402A new API `spdk_nvmf_transport_stop_listen_async` was added to stop accepting new connections
1403at the provided address. `nvmf_subsystem_remove_listener` RPC now uses this function.
1404
1405A new API `spdk_nvmf_subsystem_disconnect_host` was added to disconnect all connections
1406originating from the provided hostnqn. `nvmf_subsystem_remove_host` RPC now uses this function.
1407
1408### ocf
1409
1410Updated OCF submodule to v20.03.1
1411
1412### rpc
1413
1414New optional parameters, `enable_placement_id` and `enable_quickack` were added to the
1415`sock_impl_set_options` RPC.
1416
1417A new RPC `bdev_examine_bdev` was added to allow users to examine a bdev explicitly.
1418It can be used only if bdev_auto_examine is set to false by the RPC `bdev_set_options`.
1419
1420New optional parameters `no_wr_batching` and `control_msg_num` were added to the RPC
1421'nvmf_create_transport'.
1422
1423New RPCs, `iscsi_target_node_set_redirect` and `iscsi_target_node_request_logout`, have
1424been added, and a new optional parameter `private` has been added to the RPC
1425`iscsi_create_portal_group` to support iSCSI login redirection feature.
1426
1427A new optional parameter `ana_reporting` was added to the RPC `nvmf_create_subsystem`, and
1428a new RPC `nvmf_subsystem_listener_set_ana_state` was added for ANA reporting.
1429
1430New RPCs, `nvmf_subsystem_get_listeners` and `nvmf_subsystem_get_qpairs`, were added to
1431retrieve configuration of the NVMe-oF subsystem.
1432
1433### scsi
1434
1435Two new APIs have been added `spdk_scsi_dev_construct_ext` and
1436`spdk_scsi_dev_add_lun_ext` that allow the upper layer(e.g. vhost-scsi) to
1437receive the notification when the scsi bdev has been resized.
1438
1439The `spdk_scsi_dev_construct` and `spdk_scsi_dev_add_lun` eventually may be
1440deprecated and removed.
1441
1442### sock
1443
1444The `enable_placement_id` field was added in the `struct spdk_sock_impl_opts` to
1445make the placement_id feature configurable by users. The default setting is
1446not enabled.
1447
1448The `enable_quick_ack` field was added in the `struct spdk_sock_impl_opts` to enable
1449or disable quick ack for the POSIX sock module. The default setting is not enabled.
1450
1451### thread
1452
1453`fd_group` is applied to support interrupt mode.
1454New APIs were added to support an experimental interrupt mode.  This allows modules or
1455libraries to selectively register file descriptors that the spdk_thread can wait on,
1456as an alternative to polling. In v20.10, this functionality is enabled in a very small
1457subset of SPDK libraries and modules.
1458
1459### util
1460
1461A new utility named `fd_group` was add. It is now
1462implemented by epoll on Linux platform. It can be used by
1463spdk_thread and reactor to implement interrupt mode.
1464
1465Added `spdk_bit_pool` utility, see `bit_pool.h` for details.
1466
1467### vhost
1468
1469SPDK has switched to DPDK's rte_vhost library since 19.07 release, removed the internal
1470rte_vhost library which is used for DPDK older than 19.05, removed the experimental vhost
1471nvme target which depends on the internal rte_vhost library.
1472
1473### vpp
1474
1475Removed socket abstraction for VPP.
1476
1477## v20.07: SPDK CSI driver, new accel_fw commands, I/O abort support
1478
1479spdk_json_free_object() was added to free memory allocated by spdk_json_decode_object().
1480
1481### accel
1482
1483A new API was added `spdk_accel_get_capabilities` that allows applications to
1484query the capabilities of the currently enabled accel engine back-end.
1485
1486A new capability, CRC-32C, was added via `spdk_accel_submit_crc32c`.
1487
1488The software accel engine implementation has added support for CRC-32C.
1489
1490A new capability, compare, was added via `spdk_accel_submit_compare`.
1491
1492The software accel engine implementation has added support for compare.
1493
1494Several APIs were added to `accel_engine.h` to support batched submission
1495of operations.
1496
1497Several APIs were added to `accel_engine.h` to support dualcast operations.
1498
1499### accel_fw
1500
1501The accel_fw was updated to no longer require the app to allocate an
1502accel_task on its behalf. All public APIs now take a callback arg as
1503the parameter that used to be the accel_task.
1504
1505The accel_fw API `spdk_accel_task_size` was removed as it is no longer
1506required.
1507
1508The accel_fw was updated to support compare, dualcast, crc32c.
1509
1510The accel_fw introduced batching support for all commands in all plug-ins.
1511See docs for detailed information.
1512
1513### bdev
1514
1515A new API `spdk_bdev_abort` has been added to submit abort requests to abort all I/Os
1516whose callback context match to the bdev on the given channel.
1517
1518### build
1519
1520The fio plugins now compile to `build/fio` and are named `spdk_bdev` and `spdk_nvme`.
1521Existing fio configuration files will need to be updated.
1522
1523### dpdk
1524
1525Updated DPDK submodule to DPDK 20.05.
1526
1527### env
1528
1529Several new APIs have been added to provide greater flexibility in registering and
1530accessing polled mode PCI drivers. See `env.h` for more details.
1531
1532### idxd
1533
1534The idxd library and plug-in module for the accel_fw were updated to support
1535all accel_fw commands as well as batching.  Batching is supported both
1536through the library and the plug-in module.
1537
1538IDXD engine support for CRC-32C has been added.
1539
1540### ioat
1541
1542A new API `spdk_ioat_get_max_descriptors` was added.
1543
1544### nvme
1545
1546An `opts_size`element was added in the  `spdk_nvme_ctrlr_opts` structure
1547to solve the ABI compatibility issue between different SPDK version.
1548
1549A new API `spdk_nvme_ctrlr_cmd_abort_ext` has been added to abort previously submitted
1550commands whose callback argument match.
1551
1552Convenience functions, `spdk_nvme_print_command` and `spdk_nvme-print_completion` were added
1553to the public API.
1554
1555A new function, `spdk_nvmf_cuse_update_namespaces`, updates the cuse representation of an NVMe
1556controller.
1557
1558A new function `qpair_iterate_requests` has been added to the nvme transport interface. ALl
1559implementations of the transport interface will have to implement that function.
1560
1561### nvmf
1562
1563The NVMe-oF target no longer supports connecting scheduling configuration and instead
1564always uses what was previously called "transport" scheduling.
1565
1566`spdk_nvmf_tgt_accept` no longer exists. The accept process now occurs automatically after
1567the creation of an nvmf target and queue pairs are assigned to poll groups by the underlying
1568transport. Further, `spdk_nvmf_transport_ops` has changed such that the accept function
1569pointer no longer takes a function pointer as an argument. Instead, transports should call
1570`spdk_nvmf_tgt_new_qpair` whenever they previously would have called that callback.
1571
1572The NVMe-oF target now supports aborting any submitted NVM or Admin command. Previously,
1573the NVMe-oF target could abort only Asynchronous Event Request commands.
1574
1575### rdma
1576
1577A new `rdma` library has been added. It is an abstraction layer over different RDMA providers.
1578Two providers are available - verbs (used by default when RDMA is enabled or enabled explicitly
1579using --with-rdma=verbs) and mlx5 Direct Verbs aka DV (enabled by --with-rdma=mlx5_dv).
1580Using mlx5_dv requires libmlx5 installed on the system.
1581
1582### rpc
1583
1584Parameter `-p` or `--max-qpairs-per-ctrlr` of `nvmf_create_transport` RPC command accepted by the
1585rpc.py script is deprecated, new parameter `-m` or `--max-io-qpairs-per-ctrlr` was added.
1586
1587Added `sock_impl_get_options` and `sock_impl_set_options` RPC methods.
1588
1589Command line parameters `-r` and `--rpc-socket` will longer accept TCP ports. RPC server
1590must now be started on a Unix domain socket. Exposing RPC on the network, as well as providing
1591proper authentication (if needed) is now a responsibility of the user.
1592
1593The `bdev_set_options` RPC has a new option, `bdev_auto_examine` to control the auto examine function
1594of bdev modules.
1595
1596New RPCs `sock_impl_get_options` and `sock_impl_set_options` been added to expose new socket features.
1597See `sock` section for more details.
1598
1599### sock
1600
1601Added `spdk_sock_impl_get_opts` and `spdk_sock_impl_set_opts` functions to set/get socket layer configuration
1602options. Options can be set independently for each implementation.
1603
1604Added `recv_buf_size` and 'send_buf_size' socket layer options. They are used only in posix implementation.
1605
1606Added `uring` based socket implementation, the code is located in module/sock/uring. This feature is only
1607available in Linux which requires kernel version is greater than 5.4.3. Currently, our CI pool added the uring
1608based socket tests for iSCSI target and also the tests for SPDK NVMe-oF tcp transport.
1609
1610Added `enable_recv_pipe` socket layer option to allow disabling of double buffering on receive.
1611New option is used only in posix implementation.
1612
1613Added `enable_zerocopy_send` socket layer option to allow disabling of zero copy flow on send.
1614New option is used only in posix implementation.
1615
1616### util
1617
1618Some previously exposed CRC32 functions have been removed from the public API -
1619`spdk_crc32_update`, `spdk_crc32_table_init`, and the `spdk_crc32_table` struct.
1620
1621### vhost
1622
1623The function `spdk_vhost_blk_get_dev` has been removed.
1624
1625## v20.04: SPDK Top, IDXD, NVMe qpair groups
1626
1627IDXD engine support for compare has been added.
1628
1629### configuration
1630
1631Legacy INI style configuration for SPDK applications has been deprecated and will be
1632removed in future release.
1633Please switch to JSON-RPC configuration files and/or RPC driven run-time configuration.
1634
1635### copy
1636
1637The copy engine library, modules and public APIs have been renamed. Use of the word `copy`
1638has been replaced with the word `accel` short for accelerator in preparation for adding new
1639capabilities in the future. Additionally, APIs for what was previously called the `memcpy`
1640engine have been renamed to identify the engine as a software accelerator.
1641
1642### crypto
1643
1644Support for AES_XTS was added for the QAT polled mode driver (pmd).  The create RPC
1645`bdev_crypto_create` has 2 new optional parameters: cipher and key2. Cipher can be either
1646AES_CBC (default) or AES_XTS. AES_XTS is only valid when using the QAT polled mode driver.
1647The key2 parameter is the second key required for AES_XTS.
1648
1649### event
1650
1651Reactors now accumulate CPU stats and they are retrieved by the RPC `framework_get_reactors`.
1652
1653### idxd
1654
1655IDXD support was added in the form of a low level library that can directly
1656utilize the IDXD offload engine as well as an accel plug-in module allowing for use
1657with the generic accel framework API. IDXD is the first in a family of offload
1658engines that share the same interface, specifically DSA is added here. More info
1659can be found here: https://01.org/blogs/2019/introducing-intel-data-streaming-accelerator
1660
1661Much of the implementation models IOAT, however the low level interfaces are very
1662different. The RPC to enable IDXD requires a configuration number as well. The
1663code includes two pre-defined configurations of IDXD groups/work queues/engines. A future
1664version will provide an interface to allow for setting of individual configuration
1665parameters.
1666
1667IDXD is not yet available so this feature should be considered experimental. It will
1668be built up with additional documentation as an ongoing activity.
1669
1670### iscsi
1671
1672The iSCSI target now creates a lightweight thread per poll group instead of assuming a pool
1673of lightweight threads already exist at start up time. A poll group is a collection of
1674unrelated iSCSI connections. Each poll group is only accessed from the associated
1675lightweight thread.
1676
1677### ftl
1678
1679Several changes have been made to the `spdk_ftl_conf`, `spdk_ftl_dev_init_ops`, and
1680`spdk_ftl_attrs` structs. Please see `include/spdk/ftl.h` for more details.
1681
1682### miscellaneous
1683
1684The `--json-ignore-init-errors` command line parameter has been added to ignore
1685initialization errors on JSON config load.
1686
1687The public header file io_channel.h has been removed. Please use thread.h which has the
1688exact same API.
1689
1690### nvme
1691
1692Exported internal nvme_ctrlr_cmd_security_receive/send() APIs as public APIs with "the spdk_"
1693prefix.
1694
1695Added `priority` field in `spdk_nvme_transport_id`, this field is used to specify the priority
1696of the NVMe-oF connection, and currently it is used for NVMe-oF tcp connection.
1697
1698A new poll group API has been added to allow for pooling of nvme qpairs across a single
1699entity which can be polled for completions. This new API consists of the `spdk_nvme_poll_group`
1700family of functions. As a result of this new API, all NVMe transports are expected to implement
1701several poll group related functions.
1702
1703A new flag, `create_only`, has been added to the `spdk_nvme_io_qpair_opts` structure. This flag
1704allows a user to call `spdk_nvme_ctrlr_get_default_io_qpair` without also connecting the qpair
1705within the context of that call.
1706
1707As a result of the `create_only` flag, two new API functions, `spdk_nvme_ctrlr_connect_io_qpair`
1708and `spdk_nvme_ctrlr_disconnect_io_qpair`, have been added to facilitate connecting newly created
1709qpairs (for example, after they have been added to a poll group) and disconnecting qpairs without
1710destroying them (for example to disconnect a qpair before migrating it to a new poll group and
1711reconnecting it).
1712
1713The functions `spdk_nvme_ctrlr_alloc_cmb_io_buffer` and `spdk_nvme_ctrlr_free_cmb_io_buffer`
1714have been changed to `spdk_nvme_ctrlr_map_cmb` and `spdk_nvme_ctrlr_unmap_cmb` respectively.
1715
1716An additional function, `spdk_nvme_ctrlr_reserve_cmb`, has been added to facilitate reserving
1717the entire size of the controller memory buffer for data transfer.
1718
1719### nvme_cuse
1720
1721`spdk_nvme_cuse_get_ctrlr_name` now takes two additional parameters, `char *name` which
1722stores the pointer to the controller name, and `size_t *size` which stores the length of
1723the name. The return type has also been changed from char * to int.
1724
1725`spdk_nvme_cuse_get_ns_name` now takes two additional parameters, `char *name` which
1726stores the pointer to the namespace name, and `size_t *size` which stores the length of
1727the name. The return type has also been changed from char * to int.
1728
1729### nvme_opal
1730
1731Several public OPAL structure definitions have been changed since the last release.
1732
1733### nvmf
1734
1735`spdk_nvmf_poll_group_destroy()` is now asynchronous and accepts a completion callback.
1736
1737The NVMe-oF target now creates a lightweight thread per poll group instead of assuming a pool
1738of lightweight threads already exist at start up time. A poll group is a collection of
1739unrelated NVMe-oF connections. Each poll group is only accessed from the associated
1740lightweight thread.
1741
1742A new struct, `spdk_nvmf_subsystem_listener`, has been added to encapsulate the subsystem specific
1743nature of a listener object.
1744
1745`spdk_nvmf_tgt_listen` no longer accepts a callback function or argument. It also returns an
1746int to indicate the status of the listen call.
1747
1748The execution of `spdk_nvme_poll_group_destroy` is now asynchronous and the function accepts
1749a cb_fn and cb_arg to call upon completion.
1750
1751The execution of `spdk_nvmf_subsystem_add_listener` is now asynchronous and the function accepts
1752a cb_fn and cb_arg to call upon completion.
1753
1754The `nvmf_transport.h` header has been made public to allow custom NVMe-oF transports to integrate
1755with NVMe-oF libraries without using internal APIs.
1756
1757### ocf
1758
1759Updated the OCF submodule to OCF v20.03
1760
1761New version of OCF comes with API changes and bug fixes
1762
1763### rpc
1764
1765A new RPC `thread_set_cpumask` has been added to set the cpumask of the thread
1766to the specified value.
1767
1768A new RPC `thread_get_pollers` has been added to retrieve pollers from SPDK threads.
1769
1770A new RPC `thread_get_io_channels` has been added to retrieve I/O channels from SPDK threads.
1771
1772A new RPC `bdev_rbd_resize` has been added to resize Ceph RBD bdevs.
1773
1774### sock
1775
1776The `spdk_sock_set_priority` function has been removed since the feature to set the sock priority
1777will be contained in two new functions, i.e., `spdk_sock_listen_ext` and `spdk_sock_connect_ext`.
1778Users may now specify the priority of the socket in the opts that they want to use.
1779
1780### spdk_top
1781
1782A new application, `spdk_top`, has been added which allows users to monitor resource consumption
1783by a running SPDK application. More information on this application can be found in
1784`app/spdk_top/README`.
1785
1786### thread
1787
1788A new function `spdk_thread_lib_init_ext` has been added, and the function
1789`spdk_thread_lib_init` has been deprecated. The user of `spdk_thread_lib_init_ext` is
1790expected to implement both functions `spdk_thread_op_fn` and `spdk_thread_op_supported_fn`.
1791`spdk_thread_op_supported_fn` is called to check whether the SPDK thread operation
1792is supported. `spdk_thread_op_fn` is called to execute the SPDK thread operation.
1793Current SPDK operation types are `SPDK_THREAD_OP_NEW` and `SPDK_THREAD_OP_RESCHED`.
1794The operation `SPDK_THREAD_OP_NEW` is called each time a new thread is created.
1795The operation `SPDK_THREAD_OP_RESCHED` is called when SPDK thread needs to be rescheduled.
1796
1797A unique ID has been added for each created SPDK thread, it is retrieved by a new function
1798`spdk_thread_get_id`, and the SPDK thread which has the specific ID is got by
1799a new function `spdk_thread_get_by_id`.
1800
1801A new function `spdk_thread_cpumask` has been added to set the current thread's cpumask
1802to the specified value. The function requires the operation `SPDK_THREAD_OP_RESCHED`
1803is supported.
1804
1805A new function `spdk_poller_register_named` has been added to set arbitrary name to the
1806created poller. If NULL, the name is set to the pointer of the poller function.
1807
1808The function `spdk_thread_poll` now measures run time per call correctly on multiple SPDK
1809threads configuration, and a new function `spdk_thread_get_last_tsc` has been added to use together.
1810
1811Voluntary termination of SPDK thread has been supported by refining the functions `spdk_thread_exit`
1812and `spdk_thread_poll`.
1813
1814### util
1815
1816New functions `spdk_sn32_lt` and `spdk_sn32_gt` have been added. They compare two sequence
1817numbers based on serial number arithmetic.
1818
1819### vhost
1820
1821Poll groups per session have been replaced by SPDK threads per vhost controller.
1822
1823### vmd
1824
1825A new function, `spdk_vmd_fini`, has been added. It releases all resources acquired by the VMD
1826library through the `spdk_vmd_init` call.
1827
1828## v20.01: Optimized thin provisioning, FTL bdev, VMD hot plug, FUSED support
1829
1830### bdev
1831
1832A new function, `spdk_bdev_set_timeout`, has been added to set per descriptor I/O timeouts.
1833
1834A new class of functions `spdk_bdev_compare*`, have been added to allow native bdev support
1835of block comparisons and compare-and-write.
1836
1837A new class of bdev events, `SPDK_BDEV_EVENT_MEDIA_MANAGEMENT`, has been added to allow bdevs
1838which expose raw media to alert all I/O channels of pending media management events.
1839
1840A new API was added `spdk_bdev_io_get_aux_buf` allowing the caller to request
1841an auxiliary buffer for its own private use. The API is used in the same manner that
1842`spdk_bdev_io_get_buf` is used and the length of the buffer is always the same as the
1843bdev_io primary buffer. 'spdk_bdev_io_put_aux_buf' frees the allocated auxiliary
1844buffer.
1845
1846### blobfs
1847
1848Added boolean return value for function spdk_fs_set_cache_size to indicate its operation result.
1849
1850Added `blobfs_set_cache_size` RPC method to set cache size for blobstore filesystem.
1851
1852### blobstore
1853
1854Added new `use_extent_table` option to `spdk_blob_opts` for creating blobs with Extent Table descriptor.
1855Using this metadata format, dramatically decreases number of writes required to persist each cluster allocation
1856for thin provisioned blobs. Extent Table descriptor is enabled by default.
1857See the [Blobstore Programmer's Guide](https://spdk.io/doc/blob.html#blob_pg_cluster_layout) for more details.
1858
1859### dpdk
1860
1861Updated DPDK submodule to DPDK 19.11.
1862
1863### env_dpdk
1864
1865`spdk_env_dpdk_post_init` now takes a boolean, `legacy_mem`, as an argument.
1866
1867A new function, `spdk_env_dpdk_dump_mem_stats`, prints information about the memory consumed by DPDK to a file specified by
1868the user. A new utility, `scripts/dpdk_mem_info.py`, wraps this function and prints the output in an easy to read way.
1869
1870### event
1871
1872The functions `spdk_reactor_enable_framework_monitor_context_switch()` and
1873`spdk_reactor_framework_monitor_context_switch_enabled()` have been changed to
1874`spdk_framework_enable_context_switch_monitor()` and
1875`spdk_framework_context_switch_monitor_enabled()`, respectively.
1876
1877### ftl
1878
1879All NVMe dependencies were removed from ftl library.
1880From now ftl library is using bdev_zone API.
1881bdev_ftl becomes virtual bdev.
1882
1883`ctrlr` and `trid` fields in `spdk_ftl_dev_init_opts` structure  were replaced by
1884`base_bdev_desc`.
1885
1886`bdev_ftl_create` RPC method `trtype` and `traddr` parameters were replaced by `base_bdev`
1887parameter.
1888
1889`spdk_ftl_module_init` and `spdk_ftl_module_fini` functions were removed.
1890
1891`spdk_ftl_punit_range` and `ftl_module_init_opts` structures were removed.
1892
1893### isa-l
1894
1895Updated ISA-L submodule to commit f3993f5c0b6911 which includes implementation and
1896optimization for aarch64.
1897
1898Enabled ISA-L on aarch64 by default in addition to x86.
1899
1900### nvme
1901
1902`delayed_pcie_doorbell` parameter in `spdk_nvme_io_qpair_opts` was renamed to `delay_cmd_submit`
1903to allow reuse in other transports.
1904
1905Added RDMA WR batching to NVMf RDMA initiator. Send and receive WRs are chained together
1906and posted with a single call to ibv_post_send(receive) in the next call to qpair completion
1907processing function. Batching is controlled by 'delay_cmd_submit' qpair option.
1908
1909The NVMe-oF initiator now supports plugging out of tree NVMe-oF transports. In order
1910to facilitate this feature, several small API changes have been made:
1911
1912The `spdk_nvme_transport_id` struct now contains a trstring member used to identify the transport.
1913A new function, `spdk_nvme_transport_available_by_name`, has been added.
1914A function table, `spdk_nvme_transport_ops`, and macro, `SPDK_NVME_TRANSPORT_REGISTER`, have been added which
1915enable registering out of tree transports.
1916
1917A new function, `spdk_nvme_ns_supports_compare`, allows a user to check whether a given namespace supports the compare
1918operation.
1919
1920A new family of functions, `spdk_nvme_ns_compare*`, give the user access to submitting compare commands to NVMe namespaces.
1921
1922A new function, `spdk_nvme_ctrlr_cmd_get_log_page_ext`, gives users more granular control over the command dwords sent in
1923log page requests.
1924
1925### nvmf
1926
1927Add SockPriority option in [Transport] section, this can be used for NVMe-oF target
1928on TCP transport to set sock priority for the incoming TCP connections.
1929
1930The NVMe-oF target now supports plugging out of tree NVMe-oF transports. In order
1931to facilitate this feature, several small API changes have been made:
1932
1933The `spdk_nvme_transport_id` struct now contains a trstring member used to identify the transport.
1934`spdk_nvmf_tgt_get_transport`, `spdk_nvmf_transport_opts_init`, and `spdk_nvmf_transport_create` all have been
1935modified to take a string.
1936A function table, `spdk_nvmf_transport_ops`, and macro, `SPDK_NVMF_TRANSPORT_REGISTER`, have been added which
1937enable registering out of tree transports.
1938
1939Add `spdk_nvmf_tgt_stop_listen()` that can be used to stop listening for
1940incoming connections for specified target and trid. Listener is not stopped
1941implicitly upon destruction of a subsystem any more.
1942
1943A custom NVMe admin command handler has been added which allows the user to use the real drive
1944attributes from one of the target NVMe drives when reporting drive attributes to the initiator.
1945This handler can be enabled via the `nvmf_set_config` RPC.
1946Note: In a future version of SPDK, this handler will be enabled by default.
1947
1948The SPDK target and initiator both now include compare-and-write functionality with one caveat. If using the RDMA transport,
1949the target expects the initiator to send both the compare command and write command either with, or without inline data. The
1950SPDK initiator currently respects this requirement, but this note is included as a flag for other initiators attempting
1951compatibility with this version of SPDK.
1952
1953The `spdk_nvme_ctrlr_opts` struct has been extended with new field `transport_ack_timeout` which allows
1954to configure transport ACK timeout. Applicable for RDMA transport only.
1955
1956### rpc
1957
1958A new RPC, `bdev_zone_block_create`, enables creating an emulated zoned bdev on top of a standard block device.
1959
1960A new RPC, `bdev_ocssd_create`, enables creating an emulated zoned bdev on top of an Open Channel SSD.
1961
1962A new RPC, `blobfs_set_cache_size`, enables managing blobfs cache size.
1963
1964A new RPC, `env_dpdk_get_mem_stats`, has been added to facilitate reading DPDK related memory
1965consumption stats. Please see the env_dpdk section above for more details.
1966
1967A new RPC, `framework_get_reactors`, has been added to retrieve a list of all reactors.
1968
1969`bdev_ftl_create` now takes a `base_bdev` argument in lieu of `trtype`, `traddr`, and `punits`.
1970
1971`bdev_nvme_set_options` now allows users to disable I/O submission batching with the `-d` flag
1972
1973`bdev_nvme_cuse_register` now accepts a `name` parameter.
1974
1975`bdev_uring_create` now takes arguments for `bdev_name` and `block_size`
1976
1977`nvmf_set_config` now takes an argument to enable passthru of identify commands to base NVMe devices.
1978Please see the nvmf section above for more details.
1979
1980### scsi
1981
1982`spdk_scsi_lun_get_dif_ctx` now takes an additional argument of type `spdk_scsi_task`.
1983
1984### sock
1985
1986Added spdk_sock_writev_async for performing asynchronous writes to sockets. This call will
1987never return EAGAIN, instead queueing internally until the data has all been sent. This can
1988simplify many code flows that create pollers to continue attempting to flush writes
1989on sockets.
1990
1991Added `impl_name` parameter in spdk_sock_listen and spdk_sock_connect functions. Users may now
1992specify the sock layer implementation they'd prefer to use. Valid implementations are currently
1993"vpp" and "posix" and NULL, where NULL results in the previous behavior of the functions.
1994
1995### thread
1996
1997`spdk_thread_send_msg` now returns int indicating if the message was successfully
1998sent.
1999
2000A new function `spdk_thread_send_critical_msg`, has been added to support sending a single message from
2001a context that may be interrupted, e.g. a signal handler.
2002
2003Two new functions, `spdk_poller_pause`, and `spdk_poller_resume`, have been added to give greater control
2004of pollers to the application owner.
2005
2006### util
2007
2008`spdk_pipe`, a new utility for buffering data from sockets or files for parsing
2009has been added. The public API is available at `include/spdk/pipe.h`.
2010
2011### bdev
2012
2013Added spdk_bdev_io_get_nvme_fused_status function for translating bdev_io status to NVMe status
2014code for fused compare-and-write operation.
2015
2016Added spdk_bdev_get_acwu function for getting block device atomic compare and write unit size.
2017
2018## v19.10: Zoned bdev API, Opal bdev, NVMe character devices
2019
2020### rpc
2021
2022Many of SPDK's RPCs were renamed to be more consistent and intuitive in this release.
2023The old names will continue to function, but will display a deprecation warning.
2024
2025Added optional parameters '--arbitration-burst' and '--low/medium/high-priority-weight' to
2026'bdev_nvme_set_options' RPC method.
2027
2028Added optional parameter '--md-size' to 'construct_null_bdev' RPC method.
2029
2030Added optional parameters '--dif-type' and '--dif-is-head-of-md' to 'construct_null_bdev'
2031RPC method.
2032
2033Added `blobfs_detect` RPC method to detect whether a blobfs exists on given bdev.
2034
2035Added `blobfs_create` RPC method to build blobfs on given bdev.
2036
2037Added `blobfs_mount` RPC method to mount blobfs on given bdev to a host path by FUSE.
2038Then on the host path, user can directly do some file operations which will be mapped
2039to blobfs.
2040
2041### bdev
2042
2043Added new parameter `cdw0` to `spdk_bdev_io_complete_nvme_status()` and
2044`spdk_bdev_io_get_nvme_status()` that allows setting/getting
2045the NVMe completion queue DW0 entry. This allows vendor specific IO commands
2046to return command specific completion info back to the initiator.
2047
2048Added `spdk_bdev_get_write_unit_size()` function for retrieving required number
2049of logical blocks for write operation.
2050
2051New zone-related fields were added to the result of the `get_bdevs` RPC call:
2052
2053- `zoned`: indicates whether the device is zoned or a regular
2054  block device
2055- `zone_size`: number of blocks in a single zone
2056- `max_open_zones`: maximum number of open zones
2057- `optimal_open_zones`: optimal number of open zones
2058
2059The `zoned` field is a boolean and is always present, while the rest is only available for zoned
2060bdevs.
2061
2062A new `spdk_bdev_open_ext` function has been added and `spdk_bdev_open` function has been deprecated.
2063The new open function introduces requirement to provide callback function that will be called by
2064asynchronous event such as bdev removal. `spdk_bdev_open_ext` function takes bdev name as
2065an argument instead of bdev structure to avoid a race condition that can happen when the bdev
2066is being removed between a call to get its structure based on a name and actually openning it.
2067
2068New 'resize' event has been added to notify about change of block count property of block device.
2069Event is delivered only if block device was opened with `spdk_bdev_open_ext` function.
2070
2071### bdev zone
2072
2073Added new public header for zoned bdev. Zoned bdev is an extension
2074of the bdev interface.
2075
2076`spdk_bdev_get_zone_size()`, `spdk_bdev_get_max_open_zones()`, `spdk_bdev_get_optimal_open_zones()`
2077APIs were added for retrieving zoned device information.
2078`spdk_bdev_get_zone_info()` API was added for retrieving information about zones in zoned
2079device.
2080Added `spdk_bdev_zone_management()` API for changing zone state.
2081`spdk_bdev_zone_append()` and `spdk_bdev_zone_append_with_md()` APIs were added for
2082appending data to a zone.
2083Added `spdk_bdev_io_get_append location()` function for retrieving append location for I/O.
2084Added `spdk_bdev_is_zoned()` function for checking if bdev supports zoned namespace semantics.
2085
2086### bdev opal
2087
2088EXPERIMENTAL: A new opal bdev has been added to support management of
2089NVMe self-encrypting drives through the Opal specification. Users can
2090create opal bdevs from an NVMe namespace bdev, if the controller
2091containing that namespace supports Opal. Currently this is only
2092supported for namespace ID=1. The following RPCs have been added to
2093support Opal: `bdev_nvme_opal_init`, `bdev_nvme_opal_revert`,
2094`bdev_opal_create`, `bdev_opal_delete`, `bdev_opal_get_info`,
2095`bdev_opal_new_user`, `bdev_opal_set_lock_state`.
2096It does not yet support recreating the opal bdevs after application restart.
2097This bdev module should be considered very experimental, and the RPCs may
2098change significantly in future releases.
2099
2100### delay bdev
2101
2102The `bdev_delay_update_latency` has been added to allow users to update
2103a latency value for a given delay bdev.
2104
2105### compress bdev
2106
2107A new RPC `bdev_compress_get_orphans` has been added to list compress bdevs
2108that were not loaded due to a missing pm metadata file. In this state they
2109can only be deleted.
2110
2111### null bdev
2112
2113Metadata support has been added to Null bdev module.
2114
2115Protection information support has been added to Null bdev module.
2116
2117### nvme
2118
2119Added `no_shn_notification` to NVMe controller initialization options, users can enable
2120it for NVMe controllers.  When the option is enabled, the controller will not do the
2121shutdown process and just disable the controller, users can start their application
2122later again to initialize the controller to the ready state.
2123
2124A controller flag `SPDK_NVME_CTRLR_WRR_SUPPORTED` was added to indicate the controller
2125can support weighted round robin arbitration feature with submission queue.
2126
2127Added `arbitration_burst` option for arbitration feature, and added three
2128`low/medium/high_priority_weight` options for weighted round robin arbitration.
2129
2130Added `spdk_nvme_ns_cmd_write_uncorrectable`.
2131
2132Added new error handling and reporting functionality. This includes several
2133new API functions to facilitate applications recovering when a qpair or
2134controller fails.
2135
2136`spdk_nvme_ctrlr_reconnect_io_qpair` - Reconnects a failed I/O qpair.
2137`spdk_nvme_ctrlr_set_trid` - Sets the trid of an existing controller. Can be used to
2138change the trid for failover cases.
2139`spdk_nvme_ctrlr_is_failed` - Returns the failed state of a controller.
2140`spdk_nvme_ctrlr_fail` - Forces a controller into a failed state.
2141
2142Modified the return behavior of several API functions to better indicate to
2143applications when a qpair is failed. This list of functions includes:
2144
2145`spdk_nvme_qpair_process_completions`
2146`spdk_nvme_ns_cmd_*`
2147`spdk_nvme_ctrlr_process_admin_completions`
2148`spdk_nvme_ctrlr_cmd_*`
2149
2150These functions now return -ENXIO when the qpair or controller on which they
2151operate is failed.
2152
2153EXPERIMENTAL: Added NVMe character device support to allow to create NVMe device nodes in Linux
2154kernel for controller as well as for namespace and process ioctl requests as usual
2155from linux environment.
2156
2157### nvmf
2158
2159The `spdk_nvmf_tgt_create` function now accepts an object of type `spdk_nvmf_target_opts`
2160as its only parameter. This new structure contains the max_subsystems parameter previously
2161passed into that function.
2162
2163A new public API function `spdk_nvmf_get_tgt` has been added which allows users to
2164retrieve a pointer to an `spdk_nvmf_tgt` object by supplying its name. In the special
2165case where an RPC or application only creates a single target, this function can accept
2166a null name parameter and will return the only available target.
2167
2168The majority of the NVMe-oF RPCs now accept an optional tgt_name parameter. This will
2169allow those RPCs to work with applications that create more than one target.
2170
2171Three new NVMe-oF RPCs have been added `nvmf_create_target`, `nvmf_delete_target`, and
2172`nvmf_get_targets`. These new RPCs provide a basic interface for managing multiple target
2173objects. In SPDK the target object defines a unique discovery service. As of this release,
2174these RPCs are not intended to be used with the in-tree SPDK target applications, spdk_tgt and
2175nvmf_tgt, which use a single, global target structure. As such, they are not included in scripts/rpc.py
2176
2177Three new header functions have also been added to help deal with multiple targets.
2178`spdk_nvmf_tgt_get_name` takes a target pointer as an argument and returns its human readable name.
2179`spdk_nvmf_get_first_target` takes no arguments and returns the first target in the global list.
2180`spdk_nvmf_get_next_tgt` takes a target pointer as an argument and returns the next one in the global list.
2181
2182The `spdk_nvmf_tgt_accept` takes additional argument allowing to pass arbitrary context
2183information to the `new_qpair` callback. This will simplify the code when having multiple
2184nvmf targets or when retrieving the context information from globals is not suitable.
2185
2186### blobstore
2187
2188A new `spdk_bdev_create_bs_dev_from_desc` function has been added and `spdk_bdev_create_bs_dev`
2189function has been deprecated.
2190The new create function can cowork with `spdk_bdev_open_ext` function, which provides callback
2191function that will be called by asynchronous event such as bdev removal.
2192
2193### blobfs_bdev
2194
2195A new blobfs module `bdev` has been added to simplify the operations of blobfs on bdev.
2196
2197Function `spdk_blobfs_bdev_detect` is added to detect whether blobfs exists on the given block device.
2198
2199Function `spdk_blobfs_bdev_create` is added to create a blobfs on the given block device.
2200
2201Function `spdk_blobfs_bdev_mount` is added to mount a blobfs on the given block device to
2202a host path by FUSE. Then, a new thread is created dedicatedly for one mountpoint to handle
2203FUSE request by blobfs API.
2204
2205### build
2206
2207Option to build FUSE components into blobfs_bdev module for mounting a blobfs filesystem.
2208It requires the installation of libfuse3. By default, it is disabled. And it will be
2209enabled if run `./configure` with `--with-fuse` option.
2210
2211### iSCSI
2212
2213Portals may no longer be associated with a cpumask. The scheduling of
2214connections is moving to a more dynamic model.
2215
2216An new RPC `iscsi_portal_group_set_auth` has been added to set CHAP authentication
2217for discovery sessions specific for the existing iSCSI portal group. This RPC overwrites
2218the setting by the global parameters for the iSCSI portal group.
2219
2220### socket
2221
2222Added `spdk_sock_is_connected` to check whether the socket is currently connected.
2223`spdk_sock_group_poll` now returns number of events on success.
2224
2225### env
2226
2227Added `spdk_pci_device_unclaim()` function to cleanup pci claim file.
2228
2229### event
2230
2231`framework_start_init` RPC no longer stops the application on error during
2232initialization.
2233
2234### DPDK
2235
2236Updated DPDK submodule to DPDK 19.08.
2237
2238### ocf
2239
2240Updated OCF submodule to OCF v19.06
2241
2242Along with update, new cache mode 'write only' was added.
2243
2244New cache modes added to use via RPC, wi - write invalidate and wa - write around.
2245
2246New version of OCF provides fully asynchronous management API.
2247
2248## v19.07: NVMe-oF FC Transport, VMD, NVMe-oF Persistent reservations, Bdev I/O with separate metadata
2249
2250### ftl
2251
2252EXPERIMENTAL: Added ability to mirror writes to persistent write buffer cache
2253to allow for recovery from dirty shutdown event.
2254
2255Added handling of Asynchronous Nand Management Events (ANM).
2256
2257### vmd
2258
2259EXPERIMENTAL: Added Intel Volume Management Device (VMD) driver. VMD is an integrated
2260controller inside the CPU PCIe root complex. It enables virtual HBAs for the connected
2261NVMe SSDs. `spdk_vmd_init()` enumerates NVMe SSDs behind VMD device and hook them into
2262SPDK PCI subsystem. `spdk_nvme_probe()` or `spdk_nvme_connect()` can be used to connect
2263NVMe driver to the device located at the given transport ID.
2264
2265To obtain transport ID of NVMe SSD behind VMD `spdk_lspci` can be used.
2266
2267Current implementation does not support hotplug.
2268
2269### blobfs
2270
2271Blobfs file asynchronous operations were added to public APIs.
2272
2273### util
2274
2275A new file API `spdk_posix_file_load` was added to load file content into a data buffer.
2276
2277New APIs `spdk_dif_ctx_set_data_offset`, `spdk_dif_verify_stream`,
2278`spdk_dif_get_range_with_md`, `spdk_dif_get_length_with_md` have been added,
2279and existing APIs `spdk_dif_ctx_init`, `spdk_dif_set_md_interleave_iovs`, and
2280`spdk_dif_generate_stream` have been refined to insert or strip DIF into iovs
2281windows of any alignment.
2282
2283New APIs `spdk_dif_ctx_set_remapped_init_ref_tag`, `spdk_dif_remap_ref_tag`,
2284and `spdk_dix_remap_ref_tag` have been added to remap DIF reference tag.
2285
2286New APIs `spdk_dif_update_crc32c` and `spdk_dif_update_crc32c_stream` have been
2287added to compute CRC-32C checksum for extended LBA payload.
2288
2289Bdevperf and bdevio applications now support starting tests with application specific
2290RPCs. Please see helper Python scripts in their respective directories.
2291This is a move towards simpler RPC-only configuration for all main
2292and auxiliary applications.
2293
2294Legacy INI style configuration for SPDK applications will become deprecated in SPDK 19.10,
2295and removed in SPDK 20.01. Please consider moving to JSON-RPC configuration files and/or
2296RPC driven run-time configuration.
2297
2298### nvmf
2299
2300EXPERIMENTAL: A Fibre Channel transport that supports Broadcom HBAs has been
2301added. This depends on the FC HBA driver at
2302https://github.com/ecdufcdrvr/bcmufctdrvr. See [the documentation](https://spdk.io/doc/nvmf.html#nvmf_fc_transport)
2303for more information.
2304
2305Persistent reservation emulation has been added to the NVMe-oF target. Persistent reservation
2306state is stored in a JSON file on the local filesystem between target restart. To support this,
2307an optional parameter to the RPC method `nvmf_subsystem_add_ns` called `--ptpl-file` was added.
2308This allows the user to specify which file to store the persistent reservation state in.  Note
2309that this is done per namespace.
2310
2311The c2h success optimization under which a command capsule response is not sent
2312for reads is turned on by default. A config knob was added to allow disabling
2313the optimization. This will mostly be used for integration testing with 5.0.x kernels
2314while some compatibility fixes make their way down the pipeline for 5.1.x kernels.
2315
2316The sock priority setting of the TCP connection owned by the tcp transport is added. It is
2317used to optimize the TCP connection performance under designated traffic classes. And the
2318priority is used to differentiate the sock priority between SPDK NVMe-oF TCP target application
2319and other TCP based applications.
2320
2321Shared receive queue can now be disabled even for NICs that support it using the
2322`nvmf_create_transport` RPC method parameter `no_srq`. The actual use of a shared
2323receive queue is predicated on hardware support when this flag is not used.
2324
2325spdk_nvmf_get_optimal_poll_group was added, which is used to return the optimal
2326poll group for the qpair. And `ConnectionScheduler` configuration is added into the
2327[Nvmf] section in etc/spdk/nvmf.conf.in to demonstrate how to configure the connection
2328scheduling strategy among different spdk threads.
2329
2330Added infrastructure to retrieve global and per poll group NVMf statistics.
2331
2332DIF strip and insert is now supported for TCP transport. When it is enabled, DIF
2333setting is not exposed to the NVMe-oF initiator, and DIF is attached into data
2334for write I/O and stripped from data for read I/O.
2335
2336Added a field `dif_insert_or_strip` to struct spdk_nvmf_transport_opts, and
2337updated the related rpc function nvmf_create_transport to make this
2338configurable parameter available to users. The `dif_insert_or_strip` is relevant
2339for TCP transport for now and used to configure the DIF strip and insert.
2340
2341Added infrastructure to retrieve NVMf transport statistics.
2342
2343### notify
2344
2345The function `spdk_notify_get_types()` and `spdk_notify_get_events()` were
2346renamed to `spdk_notify_foreach_type()` and `spdk_notify_foreach_event()`,
2347respectively. And update type name of callback accordingly.
2348
2349### bdev
2350
2351The format of the data returned by the get_bdevs_iostat RPC has changed to
2352make it easier to parse.  It now returns an object with a "ticks" object
2353and "bdevs" array with the per-bdev statistics.
2354
2355A new bdev module `delay` has been added which simulates a drive latency when placed
2356on top of a Null bdev. This module is intended only for testing and can be created using
2357the new RPC `bdev_delay_create`. That RPC takes the name of the underlying bdev as well
2358as average and p99 latency arguments for both read and write operations. Average latency is
2359defined as a value close to what you would expect a perf tool such as FIO to report back as
2360the mean latency of all I/O submitted to the drive. p99 latency is defined as the value one
2361would expect the drive to see the slowest 1% of I/O report. For underlying drives with already
2362significant latency, the latency values provided to the drive will be additive. This should be
2363taken into account if trying to achieve an artificial latency on top of an nvme drive or aio device.
2364
2365DIF reference tag remapping is now supported for partition type virtual bdev
2366modules. When using partition type virtual bdevs, block address space is
2367remapped during I/O processing and DIF reference tag is remapped accordingly.
2368
2369Added spdk_bdev_*_with_md() functions allowing for IO with metadata being transferred in
2370separate buffer. To check support for separate metadata, use spdk_bdev_is_md_separate().
2371
2372All bdevs now have a UUID. For devices whose backing hardware does not provide a UUID,
2373one is automatically generated. Across runs of SPDK, bdevs whose UUID is automatically
2374generated may change.
2375
2376A new virtual bdev module `compress` has been added to provide compression services on top of
2377a thinly provisioned logical volume.  See documentation for complete details.
2378
2379### nvme
2380
2381Added an optional parameter `--io-queue-requests` to RPC `set_bdev_nvme_options`, which
2382can be used to change the number of requests allocated for one NVMe I/O queue.  For
2383very big I/O size, e.g. 128MiB, with this option user will not get an error due to
2384limited requests in NVMe driver layer.
2385
2386Added spdk_nvme_ctrlr_get_transport_id() to get the transport ID from a
2387previously attached controller.
2388
2389Nvme Opal library spdk_opal_cmd deprecated. Adding separate command APIs.
2390NVMe Opal library add support for activating locking SP which will make the transaction
2391from "Manufactured-Inactive" state to "Manufactured" state. Upon successfully invoking
2392of this method, lock and unlock features will be enabled.
2393NVMe Opal library add support for locking/unlocking range and list locking range info.
2394NVMe opal library add support for multiuser. Admin can enable user and add user to specific
2395locking range and the user can lock/unlock his range.
2396
2397Added spdk_nvme_ctrlr_io_cmd_raw_no_payload_build() allowing a caller to pass
2398a completely formed command to an NVMe submission queue (buffer addresses and all).
2399This is supported on the PCIe transport only.
2400
2401Added spdk_nvme_get_ctrlr_registers() to return a pointer to the virtual address
2402of the NVMe controller registers.  This is supported on the PCIe transport only.
2403
2404Added additional options to the spdk_nvme_ctrlr_alloc_qpair() option parameter
2405structure to allow caller to override the virtual and optionally physical address
2406of the submission and completion queue pair to be created.  This is supported on
2407the PCIe transport only.
2408
2409Added `disable_error_logging` to struct spdk_nvme_ctrlr_opts, which disables
2410logging of failed requests. By default logging is enabled.
2411
2412Added spdk_nvme_qpair_print_command(), spdk_nvme_qpair_print_completion() and
2413spdk_nvme_cpl_get_status_string(). Allowing for easier display of error messages.
2414
2415Added support for NVMe Sanitize command.
2416
2417### env
2418
2419The parameter `free_space` has been added to spdk_ring_enqueue() to wait when
2420the ring is almost full and resume when there is enough space available in
2421the ring.
2422
2423A new API `spdk_mempool_lookup` has been added to lookup the memory pool created
2424by the primary process.
2425
2426Added spdk_pci_get_first_device() and spdk_pci_get_next_device() to allow
2427iterating over PCI devices detected by SPDK. Because of this, all SPDK APIs
2428to attach/detach PCI devices are no longer thread safe. They are now meant to
2429be called from only a single thread only, the same only that called spdk_env_init().
2430This applies to the newly added APIs as well.
2431
2432### vpp
2433
2434SPDK now supports VPP version 19.04.2, up from VPP 18.01.
2435
2436VPP socket abstraction now uses VPP Session API, instead of VLC (VPP Communications Library).
2437This allows for better control over sessions and queues.
2438Please see VPP documentation for more details:
2439[VPP Host Stack](https://wiki.fd.io/view/VPP/HostStack)
2440
2441### sock
2442
2443Add spdk_sock_get_optimal_sock_group(), which returns the optimal sock group for
2444this socket. When a socket is created, it is often assigned to a sock group using
2445spdk_sock_group_add_sock so that a set of sockets can be polled more efficiently.
2446For some network devices, it is optimal to assign particular sockets to specific
2447sock groups. This API is intended to provide the user with that information.
2448
2449spdk_sock_group_get_ctx() was added to return the context of the spdk_sock_group.
2450spdk_sock_group_create() is updated to allow input the user provided ctx.
2451spdk_sock_set_priority() is added to set the priority of the socket.
2452
2453### rpc
2454
2455Added thread_get_stats RPC method to retrieve existing statistics.
2456
2457Added nvmf_get_stats RPC method to retrieve NVMf subsystem statistics.
2458
2459Response buffers for RPC requests are now always pre-allocated, which implies
2460that all spdk_jsonrpc_begin_result() calls always succeed and return a valid
2461buffer for JSON response. RPC calls no longer need to check if the buffer is
2462non-NULL.
2463
2464Added SPDK_RPC_REGISTER_ALIAS_DEPRECATED to help with deprecation process when
2465renaming existing RPC. First time a deprecated alias is used, it will print
2466a warning message.
2467
2468RPC `get_rpc_methods` was renamed `rpc_get_methods`. The old name is still usable,
2469but is now deprecated.
2470
2471### blobstore
2472
2473A snapshot can now be deleted if there is only a single clone on top of it.
2474
2475### build
2476
2477Preliminary support for cross compilation is now available. Targeting an older
2478CPU on the same architecture using your native compiler can be accomplished by
2479using the `--target-arch` option to `configure` as follows:
2480
2481~~~bash
2482./configure --target-arch=broadwell
2483~~~
2484
2485Additionally, some support for cross-compiling to other architectures has been
2486added via the `--cross-prefix` argument to `configure`. To cross-compile, set CC
2487and CXX to the cross compilers, then run configure as follows:
2488
2489~~~bash
2490./configure --target-arch=aarm64 --cross-prefix=aarch64-linux-gnu
2491~~~
2492
2493### vhost
2494
2495A security vulnerability has been identified and fixed in SPDK Vhost-SCSI target.
2496A malicious client (e.g. a virtual machine) could send a carefully prepared,
2497invalid I/O request to crash the entire SPDK process. All users of SPDK Vhost-SCSI
2498target are strongly recommended to update. All SPDK versions < 19.07 are affected.
2499
2500By default, SPDK will now rely on upstream DPDK's rte_vhost instead of its fork
2501located inside SPDK repo. The internal fork is still kept around to support older
2502DPDK versions, but is considered legacy and will be eventually removed.
2503
2504`configure` will now automatically use the upstream rte_vhost if the used DPDK
2505version is >= 19.05.
2506
2507spdk_vhost_init() is now asynchronous and accepts a completion callback.
2508
2509### iscsi target
2510
2511A security vulnerability has been identified and fixed in SPDK iSCSI target.
2512A malicious client (e.g. an iSCSI initiator) could send a carefully prepared,
2513invalid I/O request to crash the entire SPDK process. All users of SPDK iSCSI
2514target are strongly recommended to update. All SPDK versions < 19.07 are affected.
2515
2516### thread
2517
2518Exposed spdk_set_thread() in order for applications to associate
2519with SPDK thread when necessary.
2520
2521Added spdk_thread_destroy() to allow framework polling the thread to
2522release resources associated with that thread.
2523
2524## v19.04: Compression bdev, Notification library, NVMe Opal support
2525
2526### nvme
2527
2528Added asynchronous probe support. New APIs spdk_nvme_probe_async(),
2529spdk_nvme_connect_async() and spdk_nvme_probe_poll_async() were added to enable
2530this feature. spdk_nvme_probe_async() and spdk_nvme_connect_async() return a
2531context associated with the specified controllers. Users then call
2532spdk_nvme_probe_poll_async() until it returns 0, indicating that the operation
2533completed.
2534
2535A new qpair creation option, delay_pcie_doorbell, was added. This can be passed
2536to spdk_nvme_alloc_io_qpair(). This makes the I/O submission functions, such as
2537spdk_nvme_ns_writev(), skip ringing the submission queue doorbell. Instead the
2538doorbell will be rung as necessary inside spdk_nvme_qpair_process_completions().
2539This can result in significantly fewer MMIO writes to the doorbell register
2540under heavy load, greatly improving performance.
2541
2542spdk_nvme_ctrlr_get_regs_cmbsz() was added to report the size of the controller
2543memory buffer, if available.
2544
2545spdk_nvme_ctrlr_get_flags() was added to return controller feature
2546flags. Two flags are currently tracked:
2547SPDK_NVME_CTRLR_SGL_SUPPORTED
2548SPDK_NVME_CTRLR_SECURITY_SEND_RECV_SUPPORTED
2549
2550The NVMe hotplug poller is now able to detach devices hot-removed from the system
2551via `/sys/bus/pci/devices/<bdf>/remove` and `/sys/bus/pci/devices/<bdf>/driver/unbind`.
2552
2553Opal support was added for scan, take ownership, revert TPer, and dumping device
2554info. The nvme_manage tool can be used to perform these operations. The public
2555API functions are spdk_nvme_ctrlr_security_receive() and
2556spdk_nvme_ctrlr_security_send(). This module should be considered experimental
2557pending additional features and tests.
2558
2559The NVMe-oF initiator is now able to transfer IO whose size is more than 128KiB
2560if the corresponding NVMe-oF target allows.
2561
2562### raid
2563
2564Added new strip_size_kb rpc param on create to replace the more ambiguous
2565strip_size. The strip_size rpc param is deprecated.
2566
2567Changed the raid bdev product_name from "Pooled Device" to "Raid Volume"
2568
2569### thread
2570
2571Added spdk_thread_has_pollers() function to verify if there are any registered
2572pollers to be run on the thread. Added spdk_thread_is_idle() function to check
2573if there are any scheduled operations to be performed on the thread at given
2574time.
2575
2576spdk_thread_create() now takes an optional CPU affinity mask that is passed to
2577the scheduler.
2578
2579spdk_thread_lib_init() now takes an optional context size. For each thread
2580created, an additional region of memory of this size will be allocated. A
2581pointer to this region of memory can be obtained by calling
2582spdk_thread_get_ctx(). The inverse operation is also available via
2583spdk_thread_get_from_ctx().
2584
2585spdk_thread_poll() now optionally accepts the current time, in ticks. This can
2586be used to avoid some calls to spdk_get_ticks() internally.
2587
2588spdk_app_start() now only accepts a single context argument.
2589
2590### bdev
2591
2592An new API `spdk_bdev_get_data_block_size` has been added to get size of data
2593block except for metadata.
2594
2595spdk_vbdev_register() has been deprecated.  spdk_bdev_register() should be used
2596instead.
2597
2598A mechanism for acquiring and releasing data buffers from bdev modules, used
2599to perform zero copy operations, was added.
2600
2601New APIs spdk_bdev_get_md_size(), spdk_bdev_is_md_interleaved(), spdk_bdev_get_dif_type(),
2602spdk_bdev_is_dif_head_of_md(), and spdk_bdev_is_dif_check_enabled() have been
2603added to get metadata and DIF settings.
2604
2605Bdevs claimed by the `examine_config` callback will be now further examined in the
2606`examine_disk` callback.
2607
2608spdk_bdev_io_get_io_channel() was added as a convenient way to get an io_channel
2609from a bdev_io.
2610
2611### ocf
2612
2613Updated OCF submodule to OCF v19.3.2
2614
2615Added support for many-to-one configuration for OCF bdev.
2616Multiple core devices can now be cached on single cache device.
2617
2618Added persistent metadata support, allowing to restore cache state after shutdown.
2619During start of SPDK application, the devices are examined and if OCF metadata
2620is present - appropriate OCF bdevs will be recreated.
2621
2622Added Write-Back mode support. In this mode, data is first written to
2623caching device and periodically synchronized to the core devices.
2624Dirty data is saved as persistent metadata on cache device,
2625allowing for safe restore during application restart.
2626For more details please see OCF documentation:
2627[OpenCAS cache configuration](https://open-cas.github.io/cache_configuration.html)
2628
2629### NVMe-oF Target
2630
2631Support for per-device shared receive queues in the RDMA transport has been added.
2632It is enabled by default for any device that supports it.
2633
2634The size of a shared receive queue is defined by transport configuration file parameter
2635`MaxSRQDepth` and `nvmf_create_transport` RPC method parameter `max_srq_depth`.
2636Default size is 4096.
2637
2638Add model number as parameter to construct_nvmf_subsystem (-d option),
2639rather than using hardcoded define.
2640
2641DIF passthrough feature has been added. DIF setting of the allocated bdevs is
2642exposed to the NVMe-oF initiator and data with DIF from the NVMe-oF initiator is
2643passed through to the allocated bdevs.
2644
2645### env
2646
2647The `phys_addr` parameter in spdk_malloc() and spdk_zmalloc() has been deprecated.
2648For retrieving physical addresses, spdk_vtophys() should be used instead.
2649
2650spdk_realloc() has been added to reallocate DMA/shared memory.
2651
2652spdk_pci_device_is_removed() has been added to let the upper-layer SPDK drivers know
2653that device has a pending external hotremove request.
2654
2655spdk_env_fini() and spdk_env_dpdk_post_fini() were added to release any resources
2656allocated by spdk_env_init() or spdk_env_dpdk_post_init() respectively. It is expected
2657that common usage of those functions is to call them just before terminating the process.
2658
2659Added spdk_iommu_is_enabled() to report if SPDK application is using IOMMU for DMA.
2660
2661### DPDK
2662
2663Dropped support for DPDK 17.07 and earlier, which SPDK won't even compile with right now.
2664
2665Updated DPDK submodule to DPDK 19.02.
2666
2667### rpc
2668
2669New `get_spdk_version` RPC method is introduced to get version info of the running SPDK application.
2670
2671The `start_nbd_disk` RPC method now take nbd_device as an optional parameter. If nbd_device
2672is specified, use that specified nbd device. If it's not specified, pick available one.
2673
2674### iSCSI target
2675
2676DIF strip and insert is now supported. DIF settings are not exposed to the iSCSI initiator.
2677DIF is attached into data for write I/O and stripped from data for read I/O.
2678
2679### vhost
2680
2681Added experimental support for running with the external, upstream rte_vhost library.
2682This can be enabled by configuring SPDK with an `--without-internal-vhost-lib` flag.
2683The minimum supported rte_vhost version (DPDK version) is 19.05-rc1.
2684
2685As a result of fuzz testing, a lot of data races in vhost-scsi LUN hotplug path were identified and
2686fixed. Those data races could have potentially resulted in SPDK crashes, RPC hangs, or memory leaks
2687if Vhost-SCSI LUN hotplug RPCs were executed while connected VMs were in the middle of restarting.
2688
2689The SCSI target id in `add_vhost_scsi_lun` RPC is now optional. If `-1` is passed, the first
2690unoccupied target id will be used.
2691
2692### AIO
2693
2694AIO bdev module can now reap I/O completions directly from userspace, significantly improving
2695the overall performance.
2696
2697### blobfs
2698
2699Synchronous IO operations no longer use spdk_io_channel, but instead use
2700spdk_fs_thread_ctx. The behavior is otherwise identical.
2701
2702### OCF
2703
2704Added support for caching multiple bdevs using a single bdev as a cache.
2705
2706### notify
2707
2708Added the notify library that provides a high performance local event bus
2709between libraries. Example usage was added to bdev module, which reports
2710notifications for added and removed bdevs via RPC.
2711
2712### sock
2713
2714Added new API spdk_sock_readv() to the sock library for performing vectored
2715reads.
2716
2717### event
2718
2719The function spdk_subsystem_init() no longer requires spdk_event as an argument.
2720
2721Changed API of spdk_subsystem_config_json() to no longer be asynchronous.
2722
2723### io_uring
2724
2725A bdev module that issues I/O to kernel block devices using the new io_uring Linux kernel
2726API was added. This module requires liburing.
2727
2728### build
2729
2730Options to easily compile with profile guided optimization have been added to
2731`configure`. To use profile guided optimization with SPDK, run
2732`./configure --with-pgo-capture`, build SPDK, then run a workload of your
2733choosing. Then, simply run `./configure --with-pgo-enable` and recompile to
2734build using the generated profile data. Profile guided optimization can yield
2735very large performance improvements, especially on GCC 8 and clang 7. This may
2736be combined with link time optimization which has been available under the
2737`--enable-lto` configure option for several releases.
2738
2739### compression bdev/reduce library
2740
2741Added "reduce" block compression scheme based on using SSDs for storing
2742compressed blocks of storage and persistent memory for metadata. Please see
2743[compression](https://spdk.io/doc/bdev.html) for more details.
2744
2745## v19.01: NVMe-oF TCP/IP Transport, Open Channel SSD Flash Translation Layer, Caching bdev based on OCF, ISA-L Support, DIF/DIX library
2746
2747### ocf bdev
2748
2749New virtual bdev module based on [Open CAS Framework](https://open-cas.github.io/) has been added.
2750This module allows for the use of one bdev to act as a high performance cache in front of another bdev.
2751Please see [documentation](https://spdk.io/doc/bdev.html#bdev_config_cas) for more details.
2752Only write through mode is currently supported and this feature is considered experimental.
2753
2754### event framework
2755
2756For `spdk_app_parse_args`, add return value to the callback which parses application
2757specific command line parameters to protect SPDK applications from crashing by invalid
2758values from user input.
2759
2760By default, all SPDK applications will now reserve all hugepages at runtime. The pre-reserved
2761memory size can be still set with `-s` or `--mem-size` option, although the default value
2762was reduced down to 0.
2763
2764A custom hugetlbfs directory can now be specified via spdk_app_opts.
2765This can be used to configure hugepages with different sizes, a different size limit,
2766or different access permissions than the system's default hugepage pool.
2767SPDK applications can specify a custom hugetlbfs mount with the `--huge-dir` option.
2768
2769### environment
2770
2771spdk_vtophys() has been refactored to accept length of the translated region as a new
2772parameter. The function will now update that parameter with the largest possible value
2773for which the memory is contiguous in the physical memory address space.
2774
2775The following functions were removed:
2776
2777- spdk_pci_nvme_device_attach()
2778- spdk_pci_nvme_enumerate()
2779- spdk_pci_ioat_device_attach()
2780- spdk_pci_ioat_enumerate()
2781- spdk_pci_virtio_device_attach()
2782- spdk_pci_virtio_enumerate()
2783
2784They were replaced with generic spdk_pci_device_attach() and spdk_pci_enumerate() which
2785require a new spdk_pci_driver object to be provided. It can be one of the following:
2786
2787- spdk_pci_nvme_get_driver()
2788- spdk_pci_ioat_get_driver()
2789- spdk_pci_virtio_get_driver()
2790
2791spdk_pci_hook_device() and spdk_pci_unhook_device() were added. Those allow adding a virtual
2792spdk_pci_device into the SPDK PCI subsystem. A virtual device calls provided callbacks for
2793each BAR mapping request or PCI config access. It's attachable with spdk_pci_device_attach()
2794or spdk_pci_enumerate() like any other device.
2795
2796A new spdk_pause() function was added to pause CPU execution for an implementation specific
2797amount of time. Quoting from DPDK function this is based on: "This call is intended for
2798tight loops which poll a shared resource or wait for an event. A short pause within the loop
2799may reduce the power consumption."
2800
2801A new public header file env_dpdk.h has been introduced, and function spdk_env_dpdk_post_init
2802is added into it. If user is using DPDK, and already called rte_eal_init, then include
2803include/spdk/env_dpdk.h, and call spdk_env_dpdk_post_init() instead of spdk_env_init.
2804
2805ISA-L has been added as an SPDK submodule.  ISA-L is enabled by default on x86 architecture
2806to accelerate algorithms such as CRC for iSCSI and NVMe-oF.  Users may still disable ISA-L
2807by explicitly passing --without-isal to the configure script.
2808
2809### util
2810
2811A new uuid API `spdk_uuid_copy` was added to make a copy of the source uuid.
2812
2813An new parameter `init_crc` representing the initial CRC value was added to
2814`spdk_crc16_t10dif`. The parameter can be used to calculate a CRC value spanning
2815multiple separate buffers.
2816
2817New DIF APIs were added to generate and verify DIF by byte granularity for both DIF and DIX
2818formats. Among them, DIF with copy APIs will be usable to emulate DIF operations such as DIF
2819insert and strip.
2820
2821Added `spdk_strtol` and `spdk_strtoll` to provide additional error checking around `strtol`
2822and `strtoll`.
2823
2824Added `spdk_sprintf_append_realloc` and `spdk_vsprintf_append_realloc` for appending a string
2825with automatic buffer re-allocation.
2826
2827### nvme
2828
2829Wrapper functions spdk_nvme_ctrlr_security_send() and spdk_nvme_ctrlr_security_receive() are
2830introduced to support further security protocol development.
2831
2832admin_timeout_ms was added to NVMe controller initialization options, users
2833can change the default value when probing a controller.
2834
2835Add two new fields "header_digest" and "data_digest" in struct spdk_nvme_ctrlr_opts,
2836it will be used to enable the digest support for the NVMe/TCP transport.
2837
2838Add a new TCP/IP transport(located in lib/nvme/nvme_tcp.c) in nvme driver. With
2839this new transport, it can be used to connect the NVMe-oF target with the
2840same TCP/IP support.
2841
2842Added API, spdk_nvme_ctrlr_is_discovery(), to indicate whether the ctrlr
2843arg refers to a Discovery Controller or not.
2844
2845Added an API function `spdk_nvme_host_id_parse` and corresponding object `spdk_nvme_host_id`
2846for parsing host address and host service ID arguments on a per connection basis.
2847
2848The RPC `construct_nvme_bdev` now allows a user to specify a source address and service id for the host to
2849use when connecting to the controller backing the NVMe bdev.
2850
2851### NVMe-oF Target
2852
2853The `spdk_nvmf_tgt_opts` struct has been deprecated in favor of `spdk_nvmf_transport_opts`.
2854Users will no longer be able to specify target wide I/O parameters. `spdk_nvmf_tgt_listen`
2855will also no longer implicitly initialize a transport with the default target options (since
2856there are none). Instead, a user must manually instantiate the transport with `spdk_nvmf_transport_create`
2857prior to calling `spdk_nvmf_tgt_listen`.
2858
2859Related to the previous change, the rpc `set_nvmf_target_options` has been renamed to
2860`set_nvmf_target_max_subsystems` to indicate that this is the only target option available for the user to edit.
2861
2862Added fields `num_shared_buffers` and `buf_cache_size` in struct spdk_nvmf_transport_opts,
2863and also updated the related rpc function nvmf_create_transport, to make this
2864configurable parameter available to users. The `num_shared_buffers` is used to
2865configure the shared buffer numbers of the transport used by RDMA or TCP transport.
2866`buf_cache_size` configures number of shared buffers to cache per poll group.
2867
2868### nvmf
2869
2870Add a new TCP/IP transport (located in lib/nvmf/tcp.c). With this transport,
2871the SPDK NVMe-oF target can have a new transport, and can serve the NVMe-oF
2872protocol via TCP/IP from the host.
2873
2874Added optional mechanism to modify the RDMA transport's behavior when creating protection domains and registering memory.
2875By default, the RDMA transport will use the ibverbs library to create protection domains and register memory.
2876Using `spdk_nvme_rdma_init_hooks` will subvert that and use an existing registration.
2877
2878### bdev
2879
2880Added `enable_bdev_histogram` and `get_bdev_histogram` RPC commands to allow gathering latency data for specified bdev.
2881Please see [documentation](https://spdk.io/doc/bdev.html#rpc_bdev_histogram) for more details.
2882
2883Added `required_alignment` field to `spdk_bdev`, that specifies an alignment requirement for data buffers associated with an spdk_bdev_io.
2884Bdev layer will automatically double buffer any spdk_bdev_io that violates this alignment, before the spdk_bdev_io is submitted to the bdev module.
2885
2886On shutdown, bdev unregister now proceeds in top-down fashion, with
2887claimed bdevs skipped (these will be unregistered later, when virtual
2888bdev built on top of the respective base bdev unclaims it). This
2889allows virtual bdevs to be shut down cleanly as opposed to the
2890previous behavior that didn't differentiate between hotremove and
2891planned shutdown.
2892
2893The `delete_bdev` RPC is now deprecated. Users should instead use the specific deletion RPC
2894for the bdev type to be removed (i.e. delete_malloc_bdev).
2895
2896Added support for separate bandwidth rate limits for read and write to QoS in bdev layer.
2897
2898Bdev I/O statistics now track unmap operations.
2899
2900### logical volumes
2901
2902Logical volume bdev can now be marked as read only using `set_read_only_lvol_bdev` RPC.
2903This allows for basing clones on top of lvol_bdev without first creating a snapshot.
2904
2905Added option to change method for data erasure when deleting lvol or resizing down.
2906Default of unmapping clusters can now be changed to writing zeroes or no operation.
2907
2908Added option to change method for erasing data region on lvol store creation.
2909Default of unmapping can now be changed to writing zeroes or no operation.
2910
2911### log
2912
2913"trace flags" are now referred to as "log flags" in the SPDK log API.  The
2914set_trace_flag, clear_trace_flag and get_trace_flags RPCs are now deprecated,
2915and set_log_flag, clear_log_flag and get_log_flags RPCs have been added.
2916
2917### trace
2918
2919New `trace_record` application was added. It can be used to poll spdk trace shm file and
2920append any new trace entries into another specified file. This can help retain those entries
2921that would otherwise be overwritten in the shm file. See
2922[Capturing sufficient trace events](https://spdk.io/doc/nvmf_tgt_tracepoints.html#capture_trace_events)
2923for more details.
2924
2925Number of trace entries in circular buffer per lcore can now be assigned by starting SPDK app
2926with argument "--num-trace-entries <NUM>" provided.
2927
2928New `get_tpoint_group_mask` RPC was added to get current tpoint_group_mask, and
2929each tpoint group status.
2930New `enable_tpoint_group` and `disable_tpoint_group` RPC were added to enable or
2931disable a specific tpoint group.
2932
2933### ftl
2934
2935EXPERIMENTAL: Added basic flash translation layer module allowing for using Open Channel SSDs as
2936block devices. The module is split into the library (located in lib/ftl) and bdev_ftl
2937(lib/bdev/ftl). See the [documentation](https://spdk.io/doc/ftl.html) for more details.
2938
2939### vhost
2940
2941A security vulnerability has been identified and fixed in the SPDK vhost target.  A malicious
2942vhost client (i.e. virtual machine) could carefully construct a circular descriptor chain which
2943would result in a partial denial of service in the SPDK vhost target.  These types of descriptor
2944chains are now properly detected by the vhost target.  All SPDK vhost users serving untrusted
2945vhost clients are strongly recommended to upgrade. (Reported by Dima Stepanov and Evgeny
2946Yakovlev.)
2947
2948Vhost SCSI and Vhost Block devices can now accept multiple connections on the same socket file.
2949Each connection (internally called a vhost session) will have access to the same storage, but
2950will use different virtqueues, different features and possibly different memory.
2951
2952### vhost scsi
2953
2954SCSI target hotremove can now be performed even without the VIRTIO_SCSI_F_HOTPLUG feature negotiated.
2955Regardless of VIRTIO_SCSI_F_HOTPLUG support, the hotremoval will be still reported through SCSI sense codes.
2956
2957### DPDK
2958
2959DPDK submodule was updated to DPDK 18.11. Note that SPDK does not fully leverage the new
2960multi-process device hotplug yet and continues to work the same way it always did.
2961
2962Dropped support for DPDK 16.07 and earlier, which SPDK won't even compile with right now.
2963
2964### RPC
2965
2966The following RPC commands deprecated in the previous release are now removed:
2967
2968- construct_virtio_user_scsi_bdev
2969- construct_virtio_pci_scsi_bdev
2970- construct_virtio_user_blk_bdev
2971- construct_virtio_pci_blk_bdev
2972- remove_virtio_scsi_bdev
2973- construct_nvmf_subsystem
2974
2975### Miscellaneous
2976
2977The configure options `--with-raid` and `--without-raid` that were deprecated in the previous
2978release are now removed.
2979
2980### nbd
2981
2982Starting nbd using `spdk_nbd_start` is now performed asynchronously.
2983
2984### net framework
2985
2986Net framework initialization and finish is now done asynchronously.
2987
2988### rpc
2989
2990Added `spdk_rpc_is_method_allowed` function for checking whether method is permitted in a given state.
2991Added `spdk_rpc_get_state` to check current state of RPC server.
2992RPC `wait_subsystem_init` has been added to allow clients to block untill all subsystems are initialized.
2993
2994### json rpc
2995
2996JSON RPC client is now running in non-blocking mode. Requests are sent and received during spdk_jsonrpc_client_poll.
2997JSON RPC server can now receive a callback on connection termination or server shutdown using `spdk_jsonrpc_conn_add_close_cb`
2998and `spdk_jsonrpc_conn_del_close_cb`.
2999
3000## v18.10: Dynamic memory allocation, Crypto Virtual Bdev, jsonrpc-client, SPDKCLI iSCSI and NVMe-oF support
3001
3002### nvme
3003
3004spdk_nvme_ctrlr_cmd_security_send() and spdk_nvme_ctrlr_cmd_security_receive()
3005were added to support sending or receiving security protocol data to or from
3006nvme controller.
3007
3008spdk_nvme_ns_get_extended_sector_size() was added.  This function includes
3009the metadata size per sector (if any).  spdk_nvme_ns_get_sector_size() still
3010returns only the data size per sector, not including metadata.
3011
3012New `send_nvme_cmd` RPC was added to allow sending NVMe commands directly to NVMe controller.
3013See the [send_nvme_cmd](http://spdk.io/doc/jsonrpc.html#rpc_send_nvme_cmd) documentation
3014for more details.
3015
3016### Build System
3017
3018New `configure` options, `--with-shared` and `--without-shared`
3019[default], provide the capability to build, or not, SPDK shared libraries.
3020This includes the single SPDK shared lib encompassing all of the SPDK
3021static libs as well as individual SPDK shared libs corresponding to
3022each of the SPDK static ones.  Although the production of the shared
3023libs conforms with conventional version naming practices, such naming
3024does not at this time confer any SPDK ABI compatibility claims.
3025
3026### bdev
3027
3028spdk_bdev_alias_del_all() was added to delete all alias from block device.
3029
3030A new virtual bdev module has been added to perform at rest data encryption using the DPDK CryptoDev
3031Framework.  The module initially uses a software AESNI CBC cipher with experimental support for the
3032Intel QAT hardware accelerator also currently implemented with support for CBC cipher. Future work
3033may include additional ciphers as well as consideration for authentication.
3034
3035The RAID virtual bdev module is now always enabled by default.  The configure --with-raid and
3036--without-raid options are now ignored and deprecated and will be removed in the next release.
3037
3038Enforcement of bandwidth limits for quality of service (QoS) has been added to the bdev layer.
3039See the new [set_bdev_qos_limit](http://www.spdk.io/doc/jsonrpc.html#rpc_set_bdev_qos_limit)
3040documentation for more details. The previous set_bdev_qos_limit_iops RPC method introduced at
304118.04 release has been deprecated. The new set_bdev_qos_limit RPC method can support both
3042bandwidth and IOPS limits.
3043
3044spdk_bdev_config_json() and corresponding `get_bdevs_config` RPC was removed.
3045
3046### Environment Abstraction Layer and Event Framework
3047
3048The size parameter of spdk_mem_map_translate is now a pointer. This allows the
3049function to report back the actual size of the translation relative to the original
3050request made by the user.
3051
3052A new structure spdk_mem_map_ops has been introduced to hold memory map related
3053callbacks. This structure is now passed as the second argument of spdk_mem_map_alloc
3054in lieu of the notify callback.
3055
3056### DPDK 18.08
3057
3058The DPDK submodule has been updated to the DPDK 18.08 release. SPDK will now automatically
3059utilize DPDK's dynamic memory management with DPDK versions >= 18.05.1.
3060
3061Hugepages can be still reserved with `[-s|--mem-size <size>]` option at application startup,
3062but once we use them all up, instead of failing user allocations with -ENOMEM, we'll try
3063to dynamically reserve even more. This allows starting SPDK with `--mem-size 0` and using
3064only as many hugepages as it is really needed.
3065
3066Due to this change, the memory buffers returned by `spdk_*malloc()` are no longer guaranteed
3067to be physically contiguous.
3068
3069### I/OAT
3070
3071I/OAT driver can now reinitialize I/OAT channels after encountering DMA errors.
3072
3073### iscsi target
3074
3075Parameter names of `set_iscsi_options` and `get_iscsi_global_params` RPC
3076method for CHAP authentication in discovery sessions have been changed to
3077align with `construct_target_node` RPC method. Old names are still usable
3078but will be removed in future release.
3079
3080`set_iscsi_discovery_auth` and `set_iscsi_target_node_auth` RPC methods have
3081been added to set CHAP authentication for discovery sessions and existing
3082target nodes, respectively.
3083
3084The SPDK iSCSI target supports an AuthFile which can be used to load CHAP
3085shared secrets when the iSCSI target starts. SPDK previously provided a
3086default location for this file (`/usr/local/etc/spdk/auth.conf`) if none was
3087specified. This default has been removed. Users must now explicitly specify
3088the location of this file to load CHAP shared secrets from a file, or use
3089the related iSCSI RPC methods to add them at runtime.
3090
3091### iscsi initiator
3092
3093The SPDK iSCSI initiator is no longer considered experimental and becomes
3094a first-class citizen among bdev modules. The basic usage has been briefly
3095described in the bdev user guide: [iSCSI bdev](https://spdk.io/doc/bdev.html#bdev_config_iscsi)
3096
3097### Miscellaneous
3098
3099The SPDK application framework can now parse long name command line parameters.
3100Most single-character parameters have a long name equivalent now. See the
3101[Command Line Parameters](https://spdk.io/doc/app_overview.html) documentation
3102for details or use the `--help` command line parameter to list all available
3103params.
3104
3105bdevperf `-s` param (io size) was renamed to `-o` as `-s` had been already
3106used by existing apps for memory size.
3107
3108bdevio can now accept all SPDK command line parameters. The config now has to
3109be provided with `-c` or `--config` param.
3110
3111The following ioat/perf and nvme/perf parameters were renamed as well:
3112 `-s` (io size) to `-o`
3113 `-d` (mem size) to `-s`
3114
3115The ReactorMask config file parameter has been deprecated.  Users should
3116use the -m or --cpumask command line option to specify the CPU core mask
3117for the application.
3118
3119Default config file pathnames have been removed from iscsi_tgt, nvmf_tgt
3120and vhost.  Config file pathnames may now only be specified using the
3121-c command line option.
3122
3123Users may no longer set DPDK_DIR in their environment to specify the
3124location of the DPDK installation used to build SPDK.  Using DPDK_DIR
3125has not been the documented nor recommended way to specify the DPDK
3126location for several releases, but removing it ensures no unexpected
3127surprises for users who may have DPDK_DIR defined for other reasons.
3128Users should just use the "configure" script to specify the DPDK
3129location before building SPDK.
3130
3131Although we know that many developers still use Python 2 we are officially
3132switching to Python3 with requirement that all new code must be valid also
3133for Python 2 up to the EOL which is year 2020.
3134
3135Invoking interpreter explicitly is forbidden for executable scripts. There
3136is no need to use syntax like "python ./scripts/rpc.py". All executable
3137scripts must contain proper shebang pointing to the right interpreter.
3138Scripts without shebang mustn't be executable.
3139
3140A Python script has been added to enable conversion of old INI config file
3141to new JSON-RPC config file format. This script can be found at
3142scripts/config_converter.py. Example how this script can be used:
3143~~~{.sh}
3144cat old_format.ini | scripts/config_converter.py > new_json_format.json
3145~~~
3146
3147### Sock
3148
3149Two additional parameters were added to spdk_sock_get_addr() for the server
3150port and client port. These parameters are named "sport" and "cport"
3151respectively.
3152
3153### Virtio
3154
3155The following RPC commands have been deprecated:
3156
3157- construct_virtio_user_scsi_bdev
3158- construct_virtio_pci_scsi_bdev
3159- construct_virtio_user_blk_bdev
3160- construct_virtio_pci_blk_bdev
3161- remove_virtio_scsi_bdev
3162
3163The `construct_virtio_*` ones were replaced with a single `construct_virtio_dev`
3164command that can create any type of Virtio bdev(s). `remove_virtio_scsi_bdev`
3165was replaced with `remove_virtio_bdev` that can delete both Virtio Block and SCSI
3166devices.
3167
3168### Blobfs
3169
3170spdk_file_get_id() returning unique ID for the file was added.
3171
3172### JSON
3173
3174Added jsonrpc-client C library intended for issuing RPC commands from applications.
3175
3176Added API enabling iteration over JSON object:
3177
3178- spdk_json_find()
3179- spdk_json_find_string()
3180- spdk_json_find_array()
3181- spdk_json_object_first()
3182- spdk_json_array_first()
3183- spdk_json_next()
3184
3185### Blobstore
3186
3187Blobstore I/O operations are now based on io_units, instead of blobstore page size.
3188The io_unit size is now the same as the underlying block device's block size.
3189Logical volumes built on a block device with 512B block size can now be used as boot devices
3190in QEMU.
3191
3192### SPDKCLI
3193
3194The SPDKCLI interactive command tool for managing SPDK is no longer considered experimental.
3195Support for the iSCSI and NVMe-oF targets has been added.
3196
3197## v18.07: Raid, Infrastructure Improvements, Bug Fixes
3198
3199### bdev
3200
3201A new public header file bdev_module.h has been introduced to facilitate the
3202development of new bdev modules. This header includes an interface for the
3203spdk_bdev_part and spdk_bdev_part_base objects to enable the creation of
3204multiple virtual bdevs on top of a single base bdev and should act as the
3205primary API for module authors.
3206
3207spdk_bdev_get_opts() and spdk_bdev_set_opts() were added to set bdev-wide
3208options.
3209
3210A mechanism for handling out of memory condition errors (ENOMEM) returned from
3211I/O submission requests at the bdev layer has been added. See
3212spdk_bdev_queue_io_wait().
3213
3214The spdk_bdev_get_io_stat() function now returns cumulative totals instead of
3215resetting on each call. This allows multiple callers to query I/O statistics
3216without conflicting with each other. Existing users will need to adjust their
3217code to record the previous I/O statistics to calculate the delta between calls.
3218
3219I/O queue depth tracking and samples options have been added. See
3220spdk_bdev_get_qd(), spdk_bdev_get_qd_sampling_period(), and
3221spdk_bdev_set_qd_sampling_period().
3222
3223### RAID module
3224
3225A new bdev module called "raid" has been added as experimental module which
3226aggregates underlying NVMe bdevs and exposes a single raid bdev. Please note
3227that vhost will not work with this module because it does not yet have support
3228for multi-element io vectors.
3229
3230### Log
3231
3232The debug log component flag available on several SPDK applications has been
3233renamed from `-t` to `-L` to prevent confusion with tracepoints and to allow the
3234option to be added to tools that already use `-t` to mean something else.
3235
3236### Blobstore
3237
3238A new function, spdk_bs_dump(), has been added that dumps all of the contents of
3239a blobstore to a file pointer. This includes the metadata and is very useful for
3240debugging.
3241
3242Two new operations have been added for thin-provisioned blobs.
3243spdk_bs_inflate_blob() will allocate clusters for all thinly provisioned regions
3244of the blob and populate them with the correct data by reading from the backing
3245blob(s). spdk_bs_blob_decouple_parent() works similarly, but will only allocate
3246clusters that correspond to data in the blob's immediate parent. Clusters
3247allocated to grandparents or that aren't allocated at all will remain
3248thin-provisioned.
3249
3250### BlobFS
3251
3252Changed the return type of spdk_file_truncate() from void to int to allow the
3253propagation of `ENOMEM` errors.
3254
3255### NVMe Driver
3256
3257The new API functions spdk_nvme_qpair_add_cmd_error_injection() and
3258spdk_nvme_qpair_remove_cmd_error_injection() have been added for NVMe error
3259emulation. Users can set a specified command to fail with a particular error
3260status.
3261
3262Changed the name `timeout_sec` parameter to `timeout_us` in
3263spdk_nvme_ctrlr_register_timeout_callback(), and also changed the type from
3264uint32_t to uint64_t. This will give users more fine-grained control over the
3265timeout period.
3266
3267Basic support for Open Channel SSDs was added. See nvme_ocssd.h
3268
3269### NVMe Over Fabrics
3270
3271The spdk_nvmf_tgt_destroy() function is now asynchronous and takes a callback
3272as a parameter.
3273
3274spdk_nvmf_qpair_disconnect() was added to allow the user to disconnect qpairs.
3275
3276spdk_nvmf_subsystem_get_max_namespaces() was added to query the maximum allowed
3277number of namespaces for a given subsystem.
3278
3279### Build System
3280
3281The build system now generates a combined shared library (libspdk.so) that may
3282be used in place of the individual static libraries (libspdk_*.a). The combined
3283library includes all components of SPDK and is intended to make linking against
3284SPDK easier. The static libraries are also still provided for users that prefer
3285to link only the minimal set of components required.
3286
3287### git pre-commit and pre-push hooks
3288
3289The pre-commit hook will run `scripts/check_format.sh` and verify there are no
3290formating errors before allowing `git commit` to run. The pre-push hook runs
3291`make CONFIG_WERROR=y` with and without `CONFIG_DEBUG=y` using both the gcc and
3292clang compiler before allowing `git push` to run. Following each DEBUG build
3293`test/unit/unittest.sh` is run and verified. Results are recorded in the
3294`make.log` file.
3295
3296To enable type: 'git config core.hooksPath .githooks'. To override after
3297configuration use the `git --no-verify` flag.
3298
3299### RPC
3300
3301The `start_nbd_disk` RPC method now returns the path to the kernel NBD device node
3302rather than always returning `true`.
3303
3304### DPDK 18.05
3305
3306The DPDK submodule has been rebased on the DPDK 18.05 release.  DPDK 18.05 supports
3307dynamic memory allocation, but due to some issues found after the DPDK 18.05 release,
3308that support is not enabled for SPDK 18.07.  Therefore, SPDK 18.07 will continue to use
3309the legacy memory allocation model.  The plan is to enable dynamic memory allocation
3310after the DPDK 18.08 release which should fix these issues.
3311
3312### Environment Abstraction Layer and Event Framework
3313
3314The spdk_mem_map_translate() function now takes a size parameter to indicate the size of
3315the memory region.  This can be used by environment implementations to validate the
3316requested translation.
3317
3318The I/O Channel implementation has been moved to its own library - lib/thread. The
3319public API that was previously in spdk/io_channel.h is now in spdk/thread.h The
3320file spdk/io_channel.h remains and includes spdk/thread.h.
3321
3322spdk_reactor_get_tsc_stats was added to return interesting statistics for each
3323reactor.
3324
3325### IOAT
3326
3327IOAT for copy engine is disabled by default. It can be enabled by specifying the Enable
3328option with "Yes" in `[Ioat]` section of the configuration file. The Disable option is
3329now deprecated and will be removed in a future release.
3330
3331## v18.04: Logical Volume Snapshot/Clone, iSCSI Initiator, Bdev QoS, VPP Userspace TCP/IP
3332
3333### vhost
3334
3335The SPDK vhost-scsi, vhost-blk and vhost-nvme applications have fixes to address the
3336DPDK rte_vhost vulnerability [CVE-2018-1059](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-1059).
3337Please see this [security advisory](https://access.redhat.com/security/cve/cve-2018-1059)
3338for additional information on the DPDK vulnerability.
3339
3340Workarounds have been added to ensure vhost compatibility with QEMU 2.12.
3341
3342EXPERIMENTAL: Support for vhost-nvme has been added to the SPDK vhost target. See the
3343[vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
3344
3345### Unified Target Application
3346
3347A new unified SPDK target application, `spdk_tgt`, has been added. This application combines the
3348functionality of several existing SPDK applications, including the iSCSI target, NVMe-oF target,
3349and vhost target. The new application can be managed through the existing configuration file and
3350[JSON-RPC](http://www.spdk.io/doc/jsonrpc.html) methods.
3351
3352### Env
3353
3354spdk_mempool_get_bulk() has been added to wrap DPDK rte_mempool_get_bulk().
3355
3356New memory management functions spdk_malloc(), spdk_zmalloc(), and spdk_free() have been added.
3357These new functions have a `flags` parameter that allows the user to specify whether the allocated
3358memory needs to be suitable for DMA and whether it should be shared across processes with the same
3359shm_id. The new functions are intended to replace spdk_dma_malloc() and related functions, which will
3360eventually be deprecated and removed.
3361
3362### Bdev
3363
3364A new optional bdev module interface function, `init_complete`, has been added to notify bdev modules
3365when the bdev subsystem initialization is complete. This may be useful for virtual bdevs that require
3366notification that the set of initialization examine() calls is complete.
3367
3368The bdev layer now allows modules to provide an optional per-bdev UUID, which can be retrieved with
3369the spdk_bdev_get_uuid() function.
3370
3371Enforcement of IOPS limits for quality of service (QoS) has been added to the bdev layer. See the
3372[set_bdev_qos_limit_iops](http://www.spdk.io/doc/jsonrpc.html#rpc_set_bdev_qos_limit_iops) documentation
3373for more details.
3374
3375### RPC
3376
3377The `[Rpc]` configuration file section, which was deprecated in v18.01, has been removed.
3378Users should switch to the `-r` command-line parameter instead.
3379
3380The JSON-RPC server implementation now allows up to 32 megabyte responses, growing as
3381needed; previously, the response was limited to 32 kilobytes.
3382
3383### SPDKCLI
3384
3385EXPERIMENTAL: New SPDKCLI interactive command tool for managing SPDK is available.
3386See the [SPDKCLI](http://www.spdk.io/doc/spdkcli.html) documentation for more details.
3387
3388### NVMe Driver
3389
3390EXPERIMENTAL: Support for WDS and RDS capable CMBs in NVMe controllers has been added. This support is
3391experimental pending a functional allocator to free and reallocate CMB buffers.
3392
3393spdk_nvme_ns_get_uuid() has been added to allow retrieval of per-namespace UUIDs when available.
3394
3395New API functions spdk_nvme_ctrlr_get_first_active_ns() and spdk_nvme_ctrlr_get_next_active_ns()
3396have been added to iterate active namespaces, as well as spdk_nvme_ctrlr_is_active_ns() to check if
3397a namespace ID is active.
3398
3399### NVMe-oF Target
3400
3401Namespaces may now be assigned unique identifiers via new optional `eui64` and `nguid` parameters
3402to the `nvmf_subsystem_add_ns` RPC method. Additionally, the NVMe-oF target automatically exposes
3403the backing bdev's UUID as the namespace UUID when available.
3404
3405spdk_nvmf_subsystem_remove_ns() is now asynchronous and requires a callback to indicate completion.
3406
3407### Blobstore
3408
3409A number of functions have been renamed:
3410
3411- spdk_bs_io_write_blob() => spdk_blob_io_write()
3412- spdk_bs_io_read_blob() => spdk_blob_io_read()
3413- spdk_bs_io_writev_blob() => spdk_blob_io_writev()
3414- spdk_bs_io_readv_blob() => spdk_blob_io_readv()
3415- spdk_bs_io_unmap_blob() => spdk_blob_io_unmap()
3416- spdk_bs_io_write_zeroes_blob() => spdk_blob_io_write_zeroes()
3417
3418The old names still exist but are deprecated.  They will be removed in the v18.07 release.
3419
3420spdk_blob_resize() is now an asynchronous operation to enable resizing a blob while I/O
3421are in progress to that blob on other threads.  An explicit spdk_blob_sync_md() is still
3422required to sync the updated metadata to disk.
3423
3424### Logical Volumes
3425
3426A new `destroy_lvol_bdev` RPC method to delete logical volumes has been added.
3427
3428Lvols now have their own UUIDs which replace previous LvolStoreUUID_BlobID combination.
3429
3430New Snapshot and Clone functionalities have been added. User may create Snapshots of existing Lvols
3431and Clones of existing Snapshots.
3432See the [lvol snapshots](http://www.spdk.io/doc/logical_volumes.html#lvol_snapshots) documentation
3433for more details.
3434
3435Resizing logical volumes is now supported via the `resize_lvol_bdev` RPC method.
3436
3437### Lib
3438
3439A set of changes were made in the SPDK's lib code altering
3440instances of calls to `exit()` and `abort()` to return a failure instead
3441wherever reasonably possible.
3442
3443spdk_app_start() no longer exit()'s on an internal failure, but
3444instead returns a non-zero error status.
3445
3446spdk_app_parse_args() no longer exit()'s on help, '-h', or an invalid
3447option, but instead returns SPDK_APP_PARSE_ARGS_HELP and
3448SPDK_APP_PARSE_ARGS_FAIL, respectively, and SPDK_APP_PARSE_ARGS_SUCCESS
3449on success.
3450
3451spdk_pci_get_device() has been deprecated and will be removed in SPDK v18.07.
3452
3453### I/O Channels
3454
3455The prototype for spdk_poller_fn() has been modified; it now returns a value indicating
3456whether or not the poller did any work.  Existing pollers will need to be updated to
3457return a value.
3458
3459### iSCSI Target
3460
3461The SPDK iSCSI target now supports the fd.io Vector Packet Processing (VPP) framework userspace
3462TCP/IP stack. See the [iSCSI VPP documentation](http://www.spdk.io/doc/iscsi.html#vpp) for more
3463details.
3464
3465### iSCSI initiator
3466
3467An iSCSI initiator bdev module has been added to SPDK.  This module should be considered
3468experimental pending additional features and tests.  More details can be found in
3469lib/bdev/iscsi/README.
3470
3471### PMDK
3472
3473The persistent memory (PMDK) bdev module is now enabled using `--with-pmdk` instead of
3474`--with-nvml`.  This reflects the renaming of the persistent memory library from NVML to
3475PMDK.
3476
3477### Virtio Block driver
3478
3479A userspace driver for Virtio Block devices has been added. It was built on top of the
3480[Virtio](http://www.spdk.io/doc/virtio.html) library and can be managed similarly to
3481the Virtio SCSI driver. See the
3482[Virtio Block](http://www.spdk.io/doc/bdev.html#bdev_config_virtio_blk) reference for
3483more information.
3484
3485### Virtio with 2MB hugepages
3486
3487The previous 1GB hugepage limitation has now been lifted. A new `-g` command-line option
3488enables SPDK Virtio to work with 2MB hugepages.
3489See [2MB hugepages](http://www.spdk.io/doc/virtio.html#virtio_2mb) for details.
3490
3491## v18.01: Blobstore Thin Provisioning
3492
3493### Build System
3494
3495The build system now includes a `make install` rule, including support for the common
3496`DESTDIR` and `prefix` variables as used in other build systems.  Additionally, the prefix
3497may be set via the configure `--prefix` option.  Example: `make install prefix=/usr`.
3498
3499### RPC
3500
3501A JSON RPC listener is now enabled by default using a UNIX domain socket at /var/tmp/spdk.sock.
3502A -r option command line option has been added to enable an alternative UNIX domain socket location,
3503or a TCP port in the format ip_addr:tcp_port (i.e. 127.0.0.1:5260).  The Rpc configuration file
3504section is now deprecated and will be removed in the v18.04 release.
3505
3506### I/O Channels
3507
3508spdk_poller_register() and spdk_poller_unregister() were moved from the event
3509framework (include/spdk/event.h) to the I/O channel library
3510(include/spdk/io_channel.h). This allows code that doesn't depend on the event
3511framework to request registration and unregistration of pollers.
3512
3513spdk_for_each_channel() now allows asynchronous operations during iteration.
3514Instead of immediately continuing the interaction upon returning from the iteration
3515callback, the user must call spdk_for_each_channel_continue() to resume iteration.
3516
3517### Block Device Abstraction Layer (bdev)
3518
3519The poller abstraction was removed from the bdev layer. There is now a general purpose
3520abstraction for pollers available in include/spdk/io_channel.h
3521
3522### Lib
3523
3524A set of changes were made in the SPDK's lib code altering,
3525instances of calls to `exit()` and `abort()` to return a failure instead
3526wherever reasonably possible.  This has resulted in return type changes of
3527the API for:
3528
3529- spdk_env_init() from type `void` to `int`.
3530- spdk_mem_map_init() from type `void` to `int`.
3531
3532Applications making use of these APIs should be modified to check for
3533a non-zero return value instead of relying on them to fail without return.
3534
3535### NVMe Driver
3536
3537SPDK now supports hotplug for vfio-attached devices. But there is one thing keep in mind:
3538Only physical removal events are supported; removing devices via the sysfs `remove` file will not work.
3539
3540### NVMe-oF Target
3541
3542Subsystems are no longer tied explicitly to CPU cores. Instead, connections are handed out to the available
3543cores round-robin. The "Core" option in the configuration file has been removed.
3544
3545### Blobstore
3546
3547A number of functions have been renamed:
3548
3549- spdk_bs_md_resize_blob() => spdk_blob_resize()
3550- spdk_bs_md_sync_blob() => spdk_blob_sync_md()
3551- spdk_bs_md_close_blob() => spdk_blob_close()
3552- spdk_bs_md_get_xattr_names() => spdk_blob_get_xattr_names()
3553- spdk_bs_md_get_xattr_value() => spdk_blob_get_xattr_value()
3554- spdk_blob_md_set_xattr() => spdk_blob_set_xattr()
3555- spdk_blob_md_remove_xattr() => spdk_blob_remove_xattr()
3556- spdk_bs_md_create_blob() => spdk_bs_create_blob()
3557- spdk_bs_md_open_blob() => spdk_bs_open_blob()
3558- spdk_bs_md_delete_blob() => spdk_bs_delete_blob()
3559- spdk_bs_md_iter_first() => spdk_bs_iter_first()
3560- spdk_bs_md_iter_next() => spdk_bs_iter_next()
3561
3562The function signature of spdk_blob_close() has changed.  It now takes a struct spdk_blob * argument
3563rather than struct spdk_blob **.
3564
3565The function signature of spdk_bs_iter_next() has changed.  It now takes a struct spdk_blob * argument
3566rather than struct spdk_blob **.
3567
3568Thin provisioning support has been added to the blobstore.  It can be enabled by setting the
3569`thin_provision` flag in struct spdk_blob_opts when calling spdk_bs_create_blob_ext().
3570
3571### NBD device
3572
3573The NBD application (test/lib/bdev/nbd) has been removed; Same functionality can now be
3574achieved by using the test/app/bdev_svc application and start_nbd_disk RPC method.
3575See the [GPT](http://www.spdk.io/doc/bdev.html#bdev_config_gpt) documentation for more details.
3576
3577### FIO plugin
3578
3579SPDK `fio_plugin` now supports FIO 3.3. The support for previous FIO 2.21 has been dropped,
3580although it still remains to work for now. The new FIO contains huge amount of bugfixes and
3581it's recommended to do an update.
3582
3583### Virtio library
3584
3585Previously a part of the bdev_virtio module, now a separate library. Virtio is now available
3586via `spdk_internal/virtio.h` file. This is an internal interface to be used when implementing
3587new Virtio backends, namely Virtio-BLK.
3588
3589### iSCSI
3590
3591The MinConnectionIdleInterval parameter has been removed, and connections are no longer migrated
3592to an epoll/kqueue descriptor on the master core when idle.
3593
3594## v17.10: Logical Volumes
3595
3596### New dependencies
3597
3598libuuid was added as new dependency for logical volumes.
3599
3600libnuma is now required unconditionally now that the DPDK submodule has been updated to DPDK 17.08.
3601
3602### Block Device Abstraction Layer (bdev)
3603
3604An [fio](http://github.com/axboe/fio) plugin was added that can route
3605I/O to the bdev layer. See the [plugin documentation](https://github.com/spdk/spdk/tree/master/examples/bdev/fio_plugin/)
3606for more information.
3607
3608spdk_bdev_unmap() was modified to take an offset and a length in bytes as
3609arguments instead of requiring the user to provide an array of SCSI
3610unmap descriptors. This limits unmaps to a single contiguous range.
3611
3612spdk_bdev_write_zeroes() was introduced.  It ensures that all specified blocks will be zeroed out.
3613If a block device doesn't natively support a write zeroes command, the bdev layer emulates it using
3614write commands.
3615
3616New API functions that accept I/O parameters in units of blocks instead of bytes
3617have been added:
3618
3619- spdk_bdev_read_blocks(), spdk_bdev_readv_blocks()
3620- spdk_bdev_write_blocks(), spdk_bdev_writev_blocks()
3621- spdk_bdev_write_zeroes_blocks()
3622- spdk_bdev_unmap_blocks()
3623
3624The bdev layer now handles temporary out-of-memory I/O failures internally by queueing the I/O to be
3625retried later.
3626
3627### Linux AIO bdev
3628
3629The AIO bdev now allows the user to override the auto-detected block size.
3630
3631### NVMe driver
3632
3633The NVMe driver now recognizes the NVMe 1.3 Namespace Optimal I/O Boundary field.
3634NVMe 1.3 devices may report an optimal I/O boundary, which the driver will take
3635into account when splitting I/O requests.
3636
3637The HotplugEnable option in `[Nvme]` sections of the configuration file is now
3638"No" by default. It was previously "Yes".
3639
3640The NVMe library now includes a spdk_nvme_ns_get_ctrlr() function which returns the
3641NVMe Controller associated with a given namespace.
3642
3643The NVMe library now allows the user to specify a host identifier when attaching
3644to a controller.  The host identifier is used as part of the Reservations feature,
3645as well as in the NVMe-oF Connect command.  The default host ID is also now a
3646randomly-generated UUID, and the default host NQN uses the host ID to generate
3647a UUID-based NQN.
3648
3649spdk_nvme_connect() was added to allow the user to connect directly to a single
3650NVMe or NVMe-oF controller.
3651
3652### NVMe-oF Target (nvmf_tgt)
3653
3654The NVMe-oF target no longer requires any in-capsule data buffers to run, and
3655the feature is now entirely optional. Previously, at least 4 KiB in-capsule
3656data buffers were required.
3657
3658NVMe-oF subsystems have a new configuration option, AllowAnyHost, to control
3659whether the host NQN whitelist is enforced when accepting new connections.
3660If no Host options have been specified and AllowAnyHost is disabled, the
3661connection will be denied; this is a behavior change from previous releases,
3662which allowed any host NQN to connect if the Host list was empty.
3663AllowAnyHost is disabled by default.
3664
3665NVMe-oF namespaces may now be assigned arbitrary namespace IDs, and the number
3666of namespaces per subsystem is no longer limited.
3667
3668The NVMe-oF target now supports the Write Zeroes command.
3669
3670### Environment Abstraction Layer
3671
3672A new default value, SPDK_MEMPOOL_DEFAULT_CACHE_SIZE, was added to provide
3673additional clarity when constructing spdk_mempools. Previously, -1 could be
3674passed and the library would choose a reasonable default, but this new value
3675makes it explicit that the default is being used.
3676
3677### Blobstore
3678
3679The blobstore super block now contains a bstype field to identify the type of the blobstore.
3680Existing code should be updated to fill out bstype when calling spdk_bs_init() and spdk_bs_load().
3681
3682spdk_bs_destroy() was added to allow destroying blobstore on device
3683with an initialized blobstore.
3684
3685spdk_bs_io_readv_blob() and spdk_bs_io_writev_blob() were added to enable
3686scattered payloads.
3687
3688A CLI tool for blobstore has been added, allowing basic operations through either command
3689line or shell interface.  See the [blobcli](https://github.com/spdk/spdk/tree/master/examples/blob/cli)
3690documentation for more details.
3691
3692### Event Framework
3693
3694The ability to set a thread name, previously only used by the reactor code, is
3695now part of the spdk_thread_allocate() API.  Users may specify a thread name
3696which will show up in tools like `gdb`.
3697
3698### Log
3699
3700The spdk_trace_dump() function now takes a new parameter to allow the caller to
3701specify an output file handle (stdout or stderr, for example).
3702
3703### Logical Volumes
3704
3705Logical volumes library built on top of SPDK blobstore has been added.
3706It is possible to create logical volumes on top of other devices using RPC.
3707
3708See the [logical volumes](http://www.spdk.io/doc/logical_volumes.html) documentation for more information.
3709
3710### Persistent Memory
3711
3712A new persistent memory bdev type has been added.
3713The persistent memory block device is built on top of [libpmemblk](http://pmem.io/nvml/libpmemblk/).
3714It is possible to create pmem devices on top of pmem pool files using RPC.
3715
3716See the [Pmem Block Device](http://www.spdk.io/doc/bdev.html#bdev_config_pmem) documentation for more information.
3717
3718### Virtio SCSI driver
3719
3720A userspace driver for Virtio SCSI devices has been added.
3721The driver is capable of creating block devices on top of LUNs exposed by another SPDK vhost-scsi application.
3722
3723See the [Virtio SCSI](http://www.spdk.io/doc/virtio.html) documentation and
3724[Getting Started](http://www.spdk.io/doc/bdev.html#bdev_config_virtio_scsi) guide for more information.
3725
3726### Vhost target
3727
3728The vhost target application now supports live migration between QEMU instances.
3729
3730## v17.07: Build system improvements, userspace vhost-blk target, and GPT bdev
3731
3732### Build System
3733
3734A `configure` script has been added to simplify the build configuration process.
3735The existing CONFIG file and `make CONFIG_...` options are also still supported.
3736Run `./configure --help` for information about available configuration options.
3737
3738A DPDK submodule has been added to make building SPDK easier.  If no `--with-dpdk`
3739option is specified to configure, the SPDK build system will automatically build a
3740known-good configuration of DPDK with the minimal options enabled.  See the Building
3741section of README.md for more information.
3742
3743A [Vagrant](https://www.vagrantup.com/) setup has been added to make it easier to
3744develop and use SPDK on systems without suitable NVMe hardware.  See the Vagrant
3745section of README.md for more information.
3746
3747### Userspace vhost-blk target
3748
3749The vhost library and example app have been updated to support the vhost-blk
3750protocol in addition to the existing vhost-scsi protocol.
3751See the [vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
3752
3753### Block device abstraction layer (bdev)
3754
3755A GPT virtual block device has been added, which automatically exposes GPT partitions
3756with a special SPDK-specific partition type as bdevs.
3757See the [GPT bdev documentation](http://www.spdk.io/doc/bdev.md#bdev_config_gpt) for
3758more information.
3759
3760### NVMe driver
3761
3762The NVMe driver has been updated to support recent Intel SSDs, including the Intel®
3763Optane™ SSD DC P4800X series.
3764
3765A workaround has been added for devices that failed to recognize register writes
3766during controller reset.
3767
3768The NVMe driver now allocates request tracking objects on a per-queue basis.  The
3769number of requests allowed on an I/O queue may be set during `spdk_nvme_probe()` by
3770modifying `io_queue_requests` in the opts structure.
3771
3772The SPDK NVMe `fio_plugin` has been updated to support multiple threads (`numjobs`).
3773
3774spdk_nvme_ctrlr_alloc_io_qpair() has been modified to allow the user to override
3775controller-level options for each individual I/O queue pair.
3776Existing callers with qprio == 0 can be updated to:
3777~~~
3778... = spdk_nvme_ctrlr_alloc_io_qpair(ctrlr, NULL, 0);
3779~~~
3780Callers that need to specify a non-default qprio should be updated to:
3781~~~
3782struct spdk_nvme_io_qpair_opts opts;
3783spdk_nvme_ctrlr_get_default_io_qpair_opts(ctrlr, &opts, sizeof(opts));
3784opts.qprio = SPDK_NVME_QPRIO_...;
3785... = spdk_nvme_ctrlr_alloc_io_qpair(ctrlr, &opts, sizeof(opts));
3786~~~
3787
3788### Environment Abstraction Layer
3789
3790The environment abstraction layer has been updated to include several new functions
3791in order to wrap additional DPDK functionality. See `include/spdk/env.h` for the
3792current set of functions.
3793
3794### SPDK Performance Analysis with Intel® VTune™ Amplifier
3795
3796Support for SPDK performance analysis has been added to Intel® VTune™ Amplifier 2018.
3797
3798This analysis provides:
3799
3800- I/O performance monitoring (calculating standard I/O metrics like IOPS, throughput, etc.)
3801- Tuning insights on the interplay of I/O and compute devices by estimating how many cores
3802  would be reasonable to provide for SPDK to keep up with a current storage workload.
3803
3804See the VTune Amplifier documentation for more information.
3805
3806## v17.03: Blobstore and userspace vhost-scsi target
3807
3808### Blobstore and BlobFS
3809
3810The blobstore is a persistent, power-fail safe block allocator designed to be
3811used as the local storage system backing a higher-level storage service.
3812See the [blobstore documentation](http://www.spdk.io/doc/blob.html) for more details.
3813
3814BlobFS adds basic filesystem functionality like filenames on top of the blobstore.
3815This release also includes a RocksDB Env implementation using BlobFS in place of the
3816kernel filesystem.
3817See the [BlobFS documentation](http://www.spdk.io/doc/blobfs.html) for more details.
3818
3819### Userspace vhost-scsi target
3820
3821A userspace implementation of the QEMU vhost-scsi protocol has been added.
3822The vhost target is capable of exporting SPDK bdevs to QEMU-based VMs as virtio devices.
3823See the [vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
3824
3825### Event framework
3826
3827The overhead of the main reactor event loop was reduced by optimizing the number of
3828calls to spdk_get_ticks() per iteration.
3829
3830### NVMe library
3831
3832The NVMe library will now automatically split readv/writev requests with scatter-gather
3833lists that do not map to valid PRP lists when the NVMe controller does not natively
3834support SGLs.
3835
3836The `identify` and `perf` NVMe examples were modified to add a consistent format for
3837specifying remote NVMe over Fabrics devices via the `-r` option.
3838This is implemented using the new `spdk_nvme_transport_id_parse()` function.
3839
3840### iSCSI Target
3841
3842The [Nvme] section of the configuration file was modified to remove the `BDF` directive
3843and replace it with a `TransportID` directive. Both local (PCIe) and remote (NVMe-oF)
3844devices can now be specified as the backing block device. A script to generate an
3845entire [Nvme] section based on the local NVMe devices attached was added at
3846`scripts/gen_nvme.sh`.
3847
3848### NVMe-oF Target
3849
3850The [Nvme] section of the configuration file was modified to remove the `BDF` directive
3851and replace it with a `TransportID` directive. Both local (PCIe) and remote (NVMe-oF)
3852devices can now be specified as the backing block device. A script to generate an
3853entire [Nvme] section based on the local NVMe devices attached was added at
3854`scripts/gen_nvme.sh`.
3855
3856## v16.12: NVMe over Fabrics host, hotplug, and multi-process
3857
3858### NVMe library
3859
3860The NVMe library has been changed to create its own request memory pool rather than
3861requiring the user to initialize the global `request_mempool` variable.  Apps can be
3862updated by simply removing the initialization of `request_mempool`.  Since the NVMe
3863library user no longer needs to know the size of the internal NVMe request
3864structure to create the pool, the `spdk_nvme_request_size()` function was also removed.
3865
3866The `spdk_nvme_ns_cmd_deallocate()` function was renamed and extended to become
3867`spdk_nvme_ns_cmd_dataset_management()`, which allows access to all of the NVMe
3868Dataset Management command's parameters.  Existing callers can be updated to use
3869`spdk_nvme_ns_cmd_dataset_management()` with `SPDK_NVME_DSM_ATTR_DEALLOCATE` as the
3870`type` parameter.
3871
3872The NVMe library SGL callback prototype has been changed to return virtual addresses
3873rather than physical addresses.  Callers of `spdk_nvme_ns_cmd_readv()` and
3874`spdk_nvme_ns_cmd_writev()` must update their `next_sge_fn` callbacks to match.
3875
3876The NVMe library now supports NVMe over Fabrics devices in addition to the existing
3877support for local PCIe-attached NVMe devices.  For an example of how to enable
3878NVMe over Fabrics support in an application, see `examples/nvme/identify` and
3879`examples/nvme/perf`.
3880
3881Hot insert/remove support for NVMe devices has been added.  To enable NVMe hotplug
3882support, an application should call the `spdk_nvme_probe()` function on a regular
3883basis to probe for new devices (reported via the existing `probe_cb` callback) and
3884removed devices (reported via a new `remove_cb` callback).  Hotplug is currently
3885only supported on Linux with the `uio_pci_generic` driver, and newly-added NVMe
3886devices must be bound to `uio_pci_generic` by an external script or tool.
3887
3888Multiple processes may now coordinate and use a single NVMe device simultaneously
3889using [DPDK Multi-process Support](http://dpdk.org/doc/guides/prog_guide/multi_proc_support.html).
3890
3891### NVMe over Fabrics target (`nvmf_tgt`)
3892
3893The `nvmf_tgt` configuration file format has been updated significantly to enable
3894new features.  See the example configuration file `etc/spdk/nvmf.conf.in` for
3895more details on the new and changed options.
3896
3897The NVMe over Fabrics target now supports virtual mode subsystems, which allow the
3898user to export devices from the SPDK block device abstraction layer as NVMe over
3899Fabrics subsystems.  Direct mode (raw NVMe device access) is also still supported,
3900and a single `nvmf_tgt` may export both types of subsystems simultaneously.
3901
3902### Block device abstraction layer (bdev)
3903
3904The bdev layer now supports scatter/gather read and write I/O APIs, and the NVMe
3905blockdev driver has been updated to support scatter/gather.  Apps can use the
3906new scatter/gather support via the `spdk_bdev_readv()` and `spdk_bdev_writev()`
3907functions.
3908
3909The bdev status returned from each I/O has been extended to pass through NVMe
3910or SCSI status codes directly in cases where the underlying device can provide
3911a more specific status code.
3912
3913A Ceph RBD (RADOS Block Device) blockdev driver has been added.  This allows the
3914`iscsi_tgt` and `nvmf_tgt` apps to export Ceph RBD volumes as iSCSI LUNs or
3915NVMe namespaces.
3916
3917### General changes
3918
3919`libpciaccess` has been removed as a dependency and DPDK PCI enumeration is
3920used instead. Prior to DPDK 16.07 enumeration by class code was not supported,
3921so for earlier DPDK versions, only Intel SSD DC P3x00 devices will be discovered
3922by the NVMe library.
3923
3924The `env` environment abstraction library has been introduced, and a default
3925DPDK-based implementation is provided as part of SPDK.  The goal of the `env`
3926layer is to enable use of alternate user-mode memory allocation and PCI access
3927libraries.  See `doc/porting.md` for more details.
3928
3929The build process has been modified to produce all of the library files in the
3930`build/lib` directory.  This is intended to simplify the use of SPDK from external
3931projects, which can now link to SPDK libraries by adding the `build/lib` directory
3932to the library path via `-L` and linking the SPDK libraries by name (for example,
3933`-lspdk_nvme -lspdk_log -lspdk_util`).
3934
3935`nvmf_tgt` and `iscsi_tgt` now have a JSON-RPC interface, which allows the user
3936to query and modify the configuration at runtime.  The RPC service is disabled by
3937default, since it currently does not provide any authentication or security
3938mechanisms; it should only be enabled on systems with controlled user access
3939behind a firewall. An example RPC client implemented in Python is provided in
3940`scripts/rpc.py`.
3941
3942## v16.08: iSCSI target, NVMe over Fabrics maturity
3943
3944This release adds a userspace iSCSI target. The iSCSI target is capable of exporting
3945NVMe devices over a network using the iSCSI protocol. The application is located
3946in app/iscsi_tgt and a documented configuration file can be found at etc/spdk/spdk.conf.in.
3947
3948This release also significantly improves the existing NVMe over Fabrics target.
3949
3950- The configuration file format was changed, which will require updates to
3951  any existing nvmf.conf files (see `etc/spdk/nvmf.conf.in`):
3952  - `SubsystemGroup` was renamed to `Subsystem`.
3953  - `AuthFile` was removed (it was unimplemented).
3954  - `nvmf_tgt` was updated to correctly recognize NQN (NVMe Qualified Names)
3955    when naming subsystems.  The default node name was changed to reflect this;
3956    it is now "nqn.2016-06.io.spdk".
3957  - `Port` and `Host` sections were merged into the `Subsystem` section
3958  - Global options to control max queue depth, number of queues, max I/O
3959    size, and max in-capsule data size were added.
3960  - The Nvme section was removed. Now a list of devices is specified by
3961    bus/device/function directly in the Subsystem section.
3962  - Subsystems now have a Mode, which can be Direct or Virtual. This is an attempt
3963    to future-proof the interface, so the only mode supported by this release
3964    is "Direct".
3965- Many bug fixes and cleanups were applied to the `nvmf_tgt` app and library.
3966- The target now supports discovery.
3967
3968This release also adds one new feature and provides some better examples and tools
3969for the NVMe driver.
3970
3971- The Weighted Round Robin arbitration method is now supported. This allows
3972  the user to specify different priorities on a per-I/O-queue basis.  To
3973  enable WRR, set the `arb_mechanism` field during `spdk_nvme_probe()`.
3974- A simplified "Hello World" example was added to show the proper way to use
3975  the NVMe library API; see `examples/nvme/hello_world/hello_world.c`.
3976- A test for measuring software overhead was added. See `test/lib/nvme/overhead`.
3977
3978## v16.06: NVMf userspace target
3979
3980This release adds a userspace NVMf (NVMe over Fabrics) target, conforming to the
3981newly-released NVMf 1.0/NVMe 1.2.1 specification.  The NVMf target exports NVMe
3982devices from a host machine over the network via RDMA.  Currently, the target is
3983limited to directly exporting physical NVMe devices, and the discovery subsystem
3984is not supported.
3985
3986This release includes a general API cleanup, including renaming all declarations
3987in public headers to include a `spdk` prefix to prevent namespace clashes with
3988user code.
3989
3990- NVMe
3991  - The `nvme_attach()` API was reworked into a new probe/attach model, which
3992  moves device detection into the NVMe library.  The new API also allows
3993  parallel initialization of NVMe controllers, providing a major reduction in
3994  startup time when using multiple controllers.
3995  - I/O queue allocation was changed to be explicit in the API.  Each function
3996  that generates I/O requests now takes a queue pair (`spdk_nvme_qpair *`)
3997  argument, and I/O queues may be allocated using
3998  `spdk_nvme_ctrlr_alloc_io_qpair()`.  This allows more flexible assignment of
3999  queue pairs than the previous model, which only allowed a single queue
4000  per thread and limited the total number of I/O queues to the lowest number
4001  supported on any attached controller.
4002  - Added support for the Write Zeroes command.
4003  - `examples/nvme/perf` can now report I/O command latency from the
4004  the controller's viewpoint using the Intel vendor-specific read/write latency
4005  log page.
4006  - Added namespace reservation command support, which can be used to coordinate
4007  sharing of a namespace between multiple hosts.
4008  - Added hardware SGL support, which enables use of scattered buffers that
4009  don't conform to the PRP list alignment and length requirements on supported
4010  NVMe controllers.
4011  - Added end-to-end data protection support, including the ability to write and
4012  read metadata in extended LBA (metadata appended to each block of data in the
4013  buffer) and separate metadata buffer modes.
4014  See `spdk_nvme_ns_cmd_write_with_md()` and `spdk_nvme_ns_cmd_read_with_md()`
4015  for details.
4016- IOAT
4017  - The DMA block fill feature is now exposed via the `ioat_submit_fill()`
4018  function.  This is functionally similar to `memset()`, except the memory is
4019  filled with an 8-byte repeating pattern instead of a single byte like memset.
4020- PCI
4021  - Added support for using DPDK for PCI device mapping in addition to the
4022  existing libpciaccess option.  Using the DPDK PCI support also allows use of
4023  the Linux VFIO driver model, which means that SPDK userspace drivers will work
4024  with the IOMMU enabled.  Additionally, SPDK applications may be run as an
4025  unprivileged user with access restricted to a specific set of PCIe devices.
4026  - The PCI library API was made more generic to abstract away differences
4027  between the underlying PCI access implementations.
4028
4029## v1.2.0: IOAT user-space driver
4030
4031This release adds a user-space driver with support for the Intel I/O Acceleration Technology
4032(I/OAT, also known as "Crystal Beach") DMA offload engine.
4033
4034- IOAT
4035  - New user-space driver supporting DMA memory copy offload
4036  - Example programs `ioat/perf` and `ioat/verify`
4037  - Kernel-mode DMA engine test driver `kperf` for performance comparison
4038- NVMe
4039  - Per-I/O flags for Force Unit Access (FUA) and Limited Retry
4040  - Public API for retrieving log pages
4041  - Reservation register/acquire/release/report command support
4042  - Scattered payload support - an alternate API to provide I/O buffers via a sequence of callbacks
4043  - Declarations and `nvme/identify` support for Intel SSD DC P3700 series vendor-specific log pages and features
4044- Updated to support DPDK 2.2.0
4045
4046## v1.0.0: NVMe user-space driver
4047
4048This is the initial open source release of the Storage Performance Development Kit (SPDK).
4049
4050Features:
4051
4052- NVMe user-space driver
4053- NVMe example programs
4054  - `examples/nvme/perf` tests performance (IOPS) using the NVMe user-space driver
4055  - `examples/nvme/identify` displays NVMe controller information in a human-readable format
4056- Linux and FreeBSD support
4057