xref: /spdk/CHANGELOG.md (revision 7192849ed24874f3e9cc31e8a33a9b32c49b9506)
1# Changelog
2
3## v20.07: (Upcoming Release)
4
5### nvmf
6
7The NVMe-oF target no longer supports connecting scheduling configuration and instead
8always uses what was previously called "transport" scheduling.
9
10`spdk_nvmf_tgt_accept` no longer takes a function pointer as an argument. New connections
11are automatically assigned to poll groups by the underlying transport. Further,
12`spdk_nvmf_transport_ops` has changed such that the accept function pointer no longer
13takes a function pointer as an argument. Instead, transports should call
14`spdk_nvmf_tgt_new_qpair` whenever they previously would have called that callback.
15
16### nvme
17
18Add `opts_size` in `spdk_nvme_ctrlr_opts` structure in order to solve the compatiblity issue
19for different ABI version.
20
21### RPC
22
23Command line parameters `-r` and `--rpc-socket` will longer accept TCP ports. RPC server
24must now be started on a Unix domain socket. Exposing RPC on the network, as well as providing
25proper authentication (if needed) is now a responsibility of the user.
26
27### build
28
29The fio plugins now compile to `build/fio` and are named `spdk_bdev` and `spdk_nvme`.
30Existing fio configuration files will need to be updated.
31
32### accel
33
34A new API was added `spdk_accel_get_capabilities` that allows applications to
35query the capabilities of the currently enabled accel engine back-end.
36
37A new capability, CRC-32C, was added via `spdk_accel_submit_crc32c`.
38
39The software accel engine implemenation has added support for CRC-32C.
40
41A new capability, compare, was added via `spdk_accel_submit_compare`.
42
43The software accel engine implemenation has added support for compare.
44
45### dpdk
46
47Updated DPDK submodule to DPDK 19.11.2, which includes fixes for DPDK vulnerabilities:
48CVE-2020-10722, CVE-2020-10723, CVE-2020-10724, CVE-2020-10725, CVE-2020-10724.
49
50### idxd
51
52IDXD engine support for CRC-32C has been added.
53
54### rdma
55
56A new `rdma` library has been added. It is an abstraction layer over different RDMA providers.
57Two providers are available - verbs (used by default when RDMA is enabled or enabled explicitly
58using --with-rdma=verbs) and mlx5 Direct Verbs aka DV (enabled by --with-rdma=mlx5_dv).
59Using mlx5_dv requires libmlx5 installed on the system.
60
61### rpc
62
63Parameter `-p` or `--max-qpairs-per-ctrlr` of `nvmf_create_transport` RPC command accepted by the
64rpc.py script is deprecated, new parameter `-m` or `--max-io-qpairs-per-ctrlr` is added.
65
66Parameter `max_qpairs_per_ctrlr` of `nvmf_create_transport` RPC command accepted by the NVMF target
67is deprecated, new parameter `max_io_qpairs_per_ctrlr` is added.
68
69Added `sock_impl_get_options` and `sock_impl_set_options` RPC methods.
70
71### sock
72
73Added `spdk_sock_impl_get_opts` and `spdk_sock_impl_set_opts` functions to set/get socket layer configuration
74options. Options can be set independently for each implementation.
75
76Added `recv_buf_size` and 'send_buf_size' socket layer options. They are used only in posix implementation.
77
78Added `uring` based socket implementation, the code is located in module/sock/uring. This feature is only
79available in Linux which requires kernel version is greater than 5.4.3. Currently, our CI pool added the uring
80based socket tests for iSCSI target and also the tests for SPDK NVMe-oF tcp transport.
81
82### vhost
83
84The function `spdk_vhost_blk_get_dev` has been removed.
85
86## v20.04:
87
88IDXD engine support for compare has been added.
89
90### configuration
91
92Legacy INI style configuration for SPDK applications has been deprecated and will be
93removed in future release.
94Please switch to JSON-RPC configuration files and/or RPC driven run-time configuration.
95
96### copy
97
98The copy engine library, modules and public APIs have been renamed. Use of the word `copy`
99has been replaced with the word `accel` short for accelerator in preparation for adding new
100capabilities in the future. Additionally, APIs for what was previously called the `memcpy`
101engine have been renamed to identify the engine as a software accelerator.
102
103### crypto
104
105Support for AES_XTS was added for the QAT polled mode driver (pmd).  The create RPC
106`bdev_crypto_create` has 2 new optional parameters: cipher and key2. Cipher can be either
107AES_CBC (default) or AES_XTS. AES_XTS is only valid when using the QAT polled mode driver.
108The key2 parameter is the second key required for AES_XTS.
109
110### event
111
112Reactors now accumulate CPU stats and they are retrieved by the RPC `framework_get_reactors`.
113
114### idxd
115
116IDXD support was added in the form of a low level library that can directly
117utilize the IDXD offload engine as well as an accel plug-in module allowing for use
118with the generic accel framework API. IDXD is the first in a family of offload
119engines that share the same interface, specifically DSA is added here. More info
120can be found here: https://01.org/blogs/2019/introducing-intel-data-streaming-accelerator
121
122Much of the implementation models IOAT, however the low level interfaces are very
123different. The RPC to enable IDXD requires a configuration number as well. The
124code includes two pre-defined configurations of IDXD groups/work queues/engines. A future
125version will provide an interface to allow for setting of individual configuration
126parameters.
127
128IDXD is not yet available so this feature should be considered experimental. It will
129be built up with additional documentation as an ongoing activity.
130
131### iscsi
132
133The iSCSI target now creates a lightweight thread per poll group instead of assuming a pool
134of lightweight threads already exist at start up time. A poll group is a collection of
135unrelated iSCSI connections. Each poll group is only accessed from the associated
136lightweight thread.
137
138### ftl
139
140Several changes have been made to the `spdk_ftl_conf`, `spdk_ftl_dev_init_ops`, and
141`spdk_ftl_attrs` structs. Please see `include/spdk/ftl.h` for more details.
142
143### miscellaneous
144
145The `--json-ignore-init-errors` command line parameter has been added to ignore
146initialization errors on JSON config load.
147
148The public header file io_channel.h has been removed. Please use thread.h which has the
149exact same API.
150
151### nvme
152
153Exported internal nvme_ctrlr_cmd_security_receive/send() APIs as public APIs with "the spdk_"
154prefix.
155
156Added `priority` field in `spdk_nvme_transport_id`, this field is used to specify the priority
157of the NVMe-oF connection, and currently it is used for NVMe-oF tcp connection.
158
159A new poll group API has been added to allow for pooling of nvme qpairs across a single
160entity which can be polled for completions. This new API consists of the `spdk_nvme_poll_group`
161family of functions. As a result of this new API, all NVMe transports are expected to implement
162several poll group related functions.
163
164A new flag, `create_only`, has been added to the `spdk_nvme_io_qpair_opts` structure. This flag
165allows a user to call `spdk_nvme_ctrlr_get_default_io_qpair` without also connecting the qpair
166within the context of that call.
167
168As a result of the `create_only` flag, two new API functions, `spdk_nvme_ctrlr_connect_io_qpair`
169and `spdk_nvme_ctrlr_disconnect_io_qpair`, have been added to facilitate connecting newly created
170qpairs (for example, after they have been added to a poll group) and disconnecting qpairs without
171destroying them (for example to disconnect a qpair before migrating it to a new poll group and
172reconnecting it).
173
174The functions `spdk_nvme_ctrlr_alloc_cmb_io_buffer` and `spdk_nvme_ctrlr_free_cmb_io_buffer`
175have been changed to `spdk_nvme_ctrlr_map_cmb` and `spdk_nvme_ctrlr_unmap_cmb` respectively.
176
177An additional function, `spdk_nvme_ctrlr_reserve_cmb`, has been added to facilitate reserving
178the entire size of the controller memory buffer for data transfer.
179
180### nvme_cuse
181
182`spdk_nvme_cuse_get_ctrlr_name` now takes two additional parameters, `char *name` which
183stores the pointer to the controller name, and `size_t *size` which stores the length of
184the name. The return type has also been changed from char * to int.
185
186`spdk_nvme_cuse_get_ns_name` now takes two additional parameters, `char *name` which
187stores the pointer to the namespace name, and `size_t *size` which stores the length of
188the name. The return type has also been changed from char * to int.
189
190### nvme_opal
191
192Several public OPAL structure definitions have been changed since the last release.
193
194### nvmf
195
196`spdk_nvmf_poll_group_destroy()` is now asynchronous and accepts a completion callback.
197
198The NVMe-oF target now creates a lightweight thread per poll group instead of assuming a pool
199of lightweight threads already exist at start up time. A poll group is a collection of
200unrelated NVMe-oF connections. Each poll group is only accessed from the associated
201lightweight thread.
202
203A new struct, `spdk_nvmf_subsystem_listener`, has been added to encapsulate the subsystem specific
204nature of a listener object.
205
206`spdk_nvmf_tgt_listen` no longer accepts a callback function or argument. It also returns an
207int to indicate the status of the listen call.
208
209The execution of `spdk_nvme_poll_group_destroy` is now asynchronous and the function accepts
210a cb_fn and cb_arg to call upon completion.
211
212The execution of `spdk_nvmf_subsystem_add_listener` is now asynchronous and the function accepts
213a cb_fn and cb_arg to call upon completion.
214
215The `nvmf_transport.h` header has been made public to allow custom NVMe-oF transports to integrate
216with NVMe-oF libraries without using internal APIs.
217
218### ocf
219
220Updated the OCF submodule to OCF v20.03
221
222New version of OCF comes with API changes and bug fixes
223
224### rpc
225
226A new RPC `thread_set_cpumask` has been added to set the cpumask of the thread
227to the specified value.
228
229A new RPC `thread_get_pollers` has been added to retrieve pollers from SPDK threads.
230
231A new RPC `thread_get_io_channels` has been added to retrieve I/O channels from SPDK threads.
232
233A new RPC `bdev_rbd_resize` has been added to resize Ceph RBD bdevs.
234
235### sock
236
237The `spdk_sock_set_priority` function has been removed since the feature to set the sock priority
238will be contained in two new functions, i.e., `spdk_sock_listen_ext` and `spdk_sock_connect_ext`.
239Users may now specify the priority of the socket in the opts that they want to use.
240
241### spdk_top
242
243A new application, `spdk_top`, has been added which allows users to monitor resource consumption
244by a running SPDK application. More information on this application can be found in
245`app/spdk_top/README`.
246
247### thread
248
249A new function `spdk_thread_lib_init_ext` has been added, and the function
250`spdk_thread_lib_init` has been deprecated. The user of `spdk_thread_lib_init_ext` is
251expected to implement both functions `spdk_thread_op_fn` and `spdk_thread_op_supported_fn`.
252`spdk_thread_op_supported_fn` is called to check whether the SPDK thread operation
253is supported. `spdk_thread_op_fn` is called to execute the SPDK thread operation.
254Current SPDK operation types are `SPDK_THREAD_OP_NEW` and `SPDK_THREAD_OP_RESCHED`.
255The operation `SPDK_THREAD_OP_NEW` is called each time a new thread is created.
256The operation `SPDK_THREAD_OP_RESCHED` is called when SPDK thread needs to be rescheduled.
257
258A unique ID has been added for each created SPDK thread, it is retrieved by a new function
259`spdk_thread_get_id`, and the SPDK thread which has the specific ID is got by
260a new function `spdk_thread_get_by_id`.
261
262A new function `spdk_thread_cpumask` has been added to set the current thread's cpumask
263to the specified value. The function requires the operation `SPDK_THREAD_OP_RESCHED`
264is supported.
265
266A new function `spdk_poller_register_named` has been added to set arbitrary name to the
267created poller. If NULL, the name is set to the pointer of the poller function.
268
269The function `spdk_thread_poll` now measures run time per call correctly on multiple SPDK
270threads configuration, and a new function `spdk_thread_get_last_tsc` has been added to use together.
271
272Voluntary termination of SPDK thread has been supported by refining the functions `spdk_thread_exit`
273and `spdk_thread_poll`.
274
275### util
276
277New functions `spdk_sn32_lt` and `spdk_sn32_gt` have been added. They compare two sequence
278numbers based on serial number arithmetic.
279
280### vhost
281
282Poll groups per session have been replaced by SPDK threads per vhost controller.
283
284### vmd
285
286A new function, `spdk_vmd_fini`, has been added. It releases all resources acquired by the VMD
287library through the `spdk_vmd_init` call.
288
289## v20.01
290
291### bdev
292
293A new function, `spdk_bdev_set_timeout`, has been added to set per descriptor I/O timeouts.
294
295A new class of functions `spdk_bdev_compare*`, have been added to allow native bdev support
296of block comparisons and compare-and-write.
297
298A new class of bdev events, `SPDK_BDEV_EVENT_MEDIA_MANAGEMENT`, has been added to allow bdevs
299which expose raw media to alert all I/O channels of pending media management events.
300
301A new API was added `spdk_bdev_io_get_aux_buf` allowing the caller to request
302an auxiliary buffer for its own private use. The API is used in the same manner that
303`spdk_bdev_io_get_buf` is used and the length of the buffer is always the same as the
304bdev_io primary buffer. 'spdk_bdev_io_put_aux_buf' frees the allocated auxiliary
305buffer.
306
307### blobfs
308
309Added boolean return value for function spdk_fs_set_cache_size to indicate its operation result.
310
311Added `blobfs_set_cache_size` RPC method to set cache size for blobstore filesystem.
312
313### blobstore
314
315Added new `use_extent_table` option to `spdk_blob_opts` for creating blobs with Extent Table descriptor.
316Using this metadata format, dramatically decreases number of writes required to persist each cluster allocation
317for thin provisioned blobs. Extent Table descriptor is enabled by default.
318See the [Blobstore Programmer's Guide](https://spdk.io/doc/blob.html#blob_pg_cluster_layout) for more details.
319
320### dpdk
321
322Updated DPDK submodule to DPDK 19.11.
323
324### env_dpdk
325
326`spdk_env_dpdk_post_init` now takes a boolean, `legacy_mem`, as an argument.
327
328A new function, `spdk_env_dpdk_dump_mem_stats`, prints information about the memory consumed by DPDK to a file specified by
329the user. A new utility, `scripts/dpdk_mem_info.py`, wraps this function and prints the output in an easy to read way.
330
331### event
332
333The functions `spdk_reactor_enable_framework_monitor_context_switch()` and
334`spdk_reactor_framework_monitor_context_switch_enabled()` have been changed to
335`spdk_framework_enable_context_switch_monitor()` and
336`spdk_framework_context_switch_monitor_enabled()`, respectively.
337
338### ftl
339
340All NVMe dependencies were removed from ftl library.
341From now ftl library is using bdev_zone API.
342bdev_ftl becomes virtual bdev.
343
344`ctrlr` and `trid` fields in `spdk_ftl_dev_init_opts` structure  were replaced by
345`base_bdev_desc`.
346
347`bdev_ftl_create` RPC method `trtype` and `traddr` parameters were replaced by `base_bdev`
348parameter.
349
350`spdk_ftl_module_init` and `spdk_ftl_module_fini` functions were removed.
351
352`spdk_ftl_punit_range` and `ftl_module_init_opts` structures were removed.
353
354### isa-l
355
356Updated ISA-L submodule to commit f3993f5c0b6911 which includes implementation and
357optimization for aarch64.
358
359Enabled ISA-L on aarch64 by default in addition to x86.
360
361### nvme
362
363`delayed_pcie_doorbell` parameter in `spdk_nvme_io_qpair_opts` was renamed to `delay_cmd_submit`
364to allow reuse in other transports.
365
366Added RDMA WR batching to NVMf RDMA initiator. Send and receive WRs are chained together
367and posted with a single call to ibv_post_send(receive) in the next call to qpair completion
368processing function. Batching is controlled by 'delay_cmd_submit' qpair option.
369
370The NVMe-oF initiator now supports plugging out of tree NVMe-oF transports. In order
371to facilitate this feature, several small API changes have been made:
372
373The `spdk_nvme_transport_id` struct now contains a trstring member used to identify the transport.
374A new function, `spdk_nvme_transport_available_by_name`, has been added.
375A function table, `spdk_nvme_transport_ops`, and macro, `SPDK_NVME_TRANSPORT_REGISTER`, have been added which
376enable registering out of tree transports.
377
378A new function, `spdk_nvme_ns_supports_compare`, allows a user to check whether a given namespace supports the compare
379operation.
380
381A new family of functions, `spdk_nvme_ns_compare*`, give the user access to submitting compare commands to NVMe namespaces.
382
383A new function, `spdk_nvme_ctrlr_cmd_get_log_page_ext`, gives users more granular control over the command dwords sent in
384log page requests.
385
386### nvmf
387
388Add SockPriority option in [Transport] section, this can be used for NVMe-oF target
389on TCP transport to set sock priority for the incomming TCP connections.
390
391The NVMe-oF target now supports plugging out of tree NVMe-oF transports. In order
392to facilitate this feature, several small API changes have been made:
393
394The `spdk_nvme_transport_id` struct now contains a trstring member used to identify the transport.
395`spdk_nvmf_tgt_get_transport`, `spdk_nvmf_transport_opts_init`, and `spdk_nvmf_transport_create` all have been
396modified to take a string.
397A function table, `spdk_nvmf_transport_ops`, and macro, `SPDK_NVMF_TRANSPORT_REGISTER`, have been added which
398enable registering out of tree transports.
399
400Add `spdk_nvmf_tgt_stop_listen()` that can be used to stop listening for
401incoming connections for specified target and trid. Listener is not stopped
402implicitly upon destruction of a subsystem any more.
403
404A custom NVMe admin command handler has been added which allows the user to use the real drive
405attributes from one of the target NVMe drives when reporting drive attributes to the initiator.
406This handler can be enabled via the `nvmf_set_config` RPC.
407Note: In a future version of SPDK, this handler will be enabled by default.
408
409The SPDK target and initiator both now include compare-and-write functionality with one caveat. If using the RDMA transport,
410the target expects the initiator to send both the compare command and write command either with, or without inline data. The
411SPDK initiator currently respects this requirement, but this note is included as a flag for other initiators attempting
412compatibility with this version of SPDK.
413
414The `spdk_nvme_ctrlr_opts` struct has been extended with new field `transport_ack_timeout` which allows
415to configure transport ACK timeout. Applicable for RDMA transport only.
416
417### rpc
418
419A new RPC, `bdev_zone_block_create`, enables creating an emulated zoned bdev on top of a standard block device.
420
421A new RPC, `bdev_ocssd_create`, enables creating an emulated zoned bdev on top of an Open Channel SSD.
422
423A new RPC, `blobfs_set_cache_size`, enables managing blobfs cache size.
424
425A new RPC, `env_dpdk_get_mem_stats`, has been added to facilitate reading DPDK related memory
426consumption stats. Please see the env_dpdk section above for more details.
427
428A new RPC, `framework_get_reactors`, has been added to retrieve a list of all reactors.
429
430`bdev_ftl_create` now takes a `base_bdev` argument in lieu of `trtype`, `traddr`, and `punits`.
431
432`bdev_nvme_set_options` now allows users to disable I/O submission batching with the `-d` flag
433
434`bdev_nvme_cuse_register` now accepts a `name` parameter.
435
436`bdev_uring_create` now takes arguments for `bdev_name` and `block_size`
437
438`nvmf_set_config` now takes an argument to enable passthru of identify commands to base NVMe devices.
439Please see the nvmf section above for more details.
440
441### scsi
442
443`spdk_scsi_lun_get_dif_ctx` now takes an additional argument of type `spdk_scsi_task`.
444
445### sock
446
447Added spdk_sock_writev_async for performing asynchronous writes to sockets. This call will
448never return EAGAIN, instead queueing internally until the data has all been sent. This can
449simplify many code flows that create pollers to continue attempting to flush writes
450on sockets.
451
452Added `impl_name` parameter in spdk_sock_listen and spdk_sock_connect functions. Users may now
453specify the sock layer implementation they'd prefer to use. Valid implementations are currently
454"vpp" and "posix" and NULL, where NULL results in the previous behavior of the functions.
455
456### thread
457
458`spdk_thread_send_msg` now returns int indicating if the message was successfully
459sent.
460
461A new function `spdk_thread_send_critical_msg`, has been added to support sending a single message from
462a context that may be interrupted, e.g. a signal handler.
463
464Two new functions, `spdk_poller_pause`, and `spdk_poller_resume`, have been added to give greater control
465of pollers to the application owner.
466
467### util
468
469`spdk_pipe`, a new utility for buffering data from sockets or files for parsing
470has been added. The public API is available at `include/spdk/pipe.h`.
471
472### bdev
473
474Added spdk_bdev_io_get_nvme_fused_status function for translating bdev_io status to NVMe status
475code for fused compare-and-write operation.
476
477Added spdk_bdev_get_acwu function for getting block device atomic compare and write unit size.
478
479## v19.10
480
481### rpc
482
483Many of SPDK's RPCs were renamed to be more consistent and intuitive in this release.
484The old names will continue to function, but will display a deprecation warning.
485
486Added optional parameters '--arbitration-burst' and '--low/medium/high-priority-weight' to
487'bdev_nvme_set_options' RPC method.
488
489Added optional parameter '--md-size' to 'construct_null_bdev' RPC method.
490
491Added optional parameters '--dif-type' and '--dif-is-head-of-md' to 'construct_null_bdev'
492RPC method.
493
494Added `blobfs_detect` RPC method to detect whether a blobfs exists on given bdev.
495
496Added `blobfs_create` RPC method to build blobfs on given bdev.
497
498Added `blobfs_mount` RPC method to mount blobfs on given bdev to a host path by FUSE.
499Then on the host path, user can directly do some file operations which will be mapped
500to blobfs.
501
502### bdev
503
504Added new parameter `cdw0` to `spdk_bdev_io_complete_nvme_status()` and
505`spdk_bdev_io_get_nvme_status()` that allows setting/getting
506the NVMe completion queue DW0 entry. This allows vendor specific IO commands
507to return commmand specific completion info back to the initiator.
508
509Added `spdk_bdev_get_write_unit_size()` function for retrieving required number
510of logical blocks for write operation.
511
512New zone-related fields were added to the result of the `get_bdevs` RPC call:
513
514 - `zoned`: indicates whether the device is zoned or a regular
515   block device
516 - `zone_size`: number of blocks in a single zone
517 - `max_open_zones`: maximum number of open zones
518 - `optimal_open_zones`: optimal number of open zones
519
520The `zoned` field is a boolean and is always present, while the rest is only available for zoned
521bdevs.
522
523A new `spdk_bdev_open_ext` function has been added and `spdk_bdev_open` function has been deprecated.
524The new open function introduces requirement to provide callback function that will be called by
525asynchronous event such as bdev removal. `spdk_bdev_open_ext` function takes bdev name as
526an argument instead of bdev structure to avoid a race condition that can happen when the bdev
527is being removed between a call to get its structure based on a name and actually openning it.
528
529New 'resize' event has been added to notify about change of block count property of block device.
530Event is delivered only if block device was opened with `spdk_bdev_open_ext` function.
531
532### bdev zone
533
534Added new public header for zoned bdev. Zoned bdev is an extension
535of the bdev interface.
536
537`spdk_bdev_get_zone_size()`, `spdk_bdev_get_max_open_zones()`, `spdk_bdev_get_optimal_open_zones()`
538APIs were added for retrieving zoned device information.
539`spdk_bdev_get_zone_info()` API was added for retrieving information about zones in zoned
540device.
541Added `spdk_bdev_zone_management()` API for changing zone state.
542`spdk_bdev_zone_append()` and `spdk_bdev_zone_append_with_md()` APIs were added for
543appending data to a zone.
544Added `spdk_bdev_io_get_append location()` function for retrieving append location for I/O.
545Added `spdk_bdev_is_zoned()` function for checking if bdev supports zoned namespace semantics.
546
547### bdev opal
548
549EXPERIMENTAL: A new opal bdev has been added to support management of
550NVMe self-encrypting drives through the Opal specification. Users can
551create opal bdevs from an NVMe namespace bdev, if the controller
552containing that namespace supports Opal. Currently this is only
553supported for namespace ID=1. The following RPCs have been added to
554support Opal: `bdev_nvme_opal_init`, `bdev_nvme_opal_revert`,
555`bdev_opal_create`, `bdev_opal_delete`, `bdev_opal_get_info`,
556`bdev_opal_new_user`, `bdev_opal_set_lock_state`.
557It does not yet support recreating the opal bdevs after application restart.
558This bdev module should be considered very experimental, and the RPCs may
559change significantly in future releases.
560
561### delay bdev
562
563The `bdev_delay_update_latency` has been added to allow users to update
564a latency value for a given delay bdev.
565
566### compress bdev
567
568A new RPC `bdev_compress_get_orphans` has been added to list compress bdevs
569that were not loaded due to a missing pm metadata file. In this state they
570can only be deleted.
571
572### null bdev
573
574Metadata support has been added to Null bdev module.
575
576Protection information support has been added to Null bdev module.
577
578### nvme
579
580Added `no_shn_notification` to NVMe controller initialization options, users can enable
581it for NVMe controllers.  When the option is enabled, the controller will not do the
582shutdown process and just disable the controller, users can start their application
583later again to initialize the controller to the ready state.
584
585A controller flag `SPDK_NVME_CTRLR_WRR_SUPPORTED` was added to indicate the controller
586can support weighted round robin arbitration feature with submission queue.
587
588Added `arbitration_burst` option for arbitration feature, and added three
589`low/medium/high_priority_weight` options for weighted round robin arbitration.
590
591Added `spdk_nvme_ns_cmd_write_uncorrectable`.
592
593Added new error handling and reporting functionality. This includes several
594new API functions to facilitate applications recovering when a qpair or
595controller fails.
596
597`spdk_nvme_ctrlr_reconnect_io_qpair` - Reconnects a failed I/O qpair.
598`spdk_nvme_ctrlr_set_trid` - Sets the trid of an existing controller. Can be used to
599change the trid for failover cases.
600`spdk_nvme_ctrlr_is_failed` - Returns the failed state of a controller.
601`spdk_nvme_ctrlr_fail` - Forces a controller into a failed state.
602
603Modified the return behavior of several API functions to better indicate to
604applications when a qpair is failed. This list of functions includes:
605
606`spdk_nvme_qpair_process_completions`
607`spdk_nvme_ns_cmd_*`
608`spdk_nvme_ctrlr_process_admin_completions`
609`spdk_nvme_ctrlr_cmd_*`
610
611These functions now return -ENXIO when the qpair or controller on which they
612operate is failed.
613
614EXPERIMENTAL: Added NVMe character device support to allow to create NVMe device nodes in Linux
615kernel for controller as well as for namespace and process ioctl requests as usual
616from linux environment.
617
618### nvmf
619
620The `spdk_nvmf_tgt_create` function now accepts an object of type `spdk_nvmf_target_opts`
621as its only parameter. This new structure contains the max_subsystems parameter previously
622passed into that function.
623
624A new public API function `spdk_nvmf_get_tgt` has been added which allows users to
625retrieve a pointer to an `spdk_nvmf_tgt` object by supplying its name. In the special
626case where an RPC or application only creates a single target, this function can accept
627a null name parameter and will return the only available target.
628
629The majority of the NVMe-oF RPCs now accept an optional tgt_name parameter. This will
630allow those RPCs to work with applications that create more than one target.
631
632Three new NVMe-oF RPCs have been added `nvmf_create_target`, `nvmf_delete_target`, and
633`nvmf_get_targets`. These new RPCs provide a basic interface for managing multiple target
634objects. In SPDK the target object defines a unique discovery service. As of this release,
635these RPCs are not intended to be used with the in-tree SPDK target applications, spdk_tgt and
636nvmf_tgt, which use a single, global target structure. As such, they are not included in scripts/rpc.py
637
638Three new header functions have also been added to help deal with multiple targets.
639`spdk_nvmf_tgt_get_name` takes a target pointer as an argument and returns its human readable name.
640`spdk_nvmf_get_first_target` takes no arguments and returns the first target in the global list.
641`spdk_nvmf_get_next_tgt` takes a target pointer as an argument and returns the next one in the global list.
642
643The `spdk_nvmf_tgt_accept` takes additional argument allowing to pass arbitrary context
644information to the `new_qpair` callback. This will simplify the code when having multiple
645nvmf targets or when retrieving the context information from globals is not suitable.
646
647### blobstore
648
649A new `spdk_bdev_create_bs_dev_from_desc` function has been added and `spdk_bdev_create_bs_dev`
650function has been deprecated.
651The new create function can cowork with `spdk_bdev_open_ext` function, which provides callback
652function that will be called by asynchronous event such as bdev removal.
653
654### blobfs_bdev
655
656A new blobfs module `bdev` has been added to simplify the operations of blobfs on bdev.
657
658Function `spdk_blobfs_bdev_detect` is added to detect whether blobfs exists on the given block device.
659
660Function `spdk_blobfs_bdev_create` is added to create a blobfs on the given block device.
661
662Function `spdk_blobfs_bdev_mount` is added to mount a blobfs on the given block device to
663a host path by FUSE. Then, a new thread is created dedicatedly for one mountpoint to handle
664FUSE request by blobfs API.
665
666### build
667
668Option to build FUSE components into blobfs_bdev module for mounting a blobfs filesystem.
669It requires the installation of libfuse3. By default, it is disabled. And it will be
670enabled if run `./configure` with `--with-fuse` option.
671
672### iSCSI
673
674Portals may no longer be associated with a cpumask. The scheduling of
675connections is moving to a more dynamic model.
676
677An new RPC `iscsi_portal_group_set_auth` has been added to set CHAP authentication
678for discovery sessions specific for the existing iSCSI portal group. This RPC overwrites
679the setting by the global parameters for the iSCSI portal group.
680
681### socket
682
683Added `spdk_sock_is_connected` to check whether the socket is currently connected.
684`spdk_sock_group_poll` now returns number of events on success.
685
686### env
687
688Added `spdk_pci_device_unclaim()` function to cleanup pci claim file.
689
690### event
691
692`framework_start_init` RPC no longer stops the application on error during
693initialization.
694
695### DPDK
696
697Updated DPDK submodule to DPDK 19.08.
698
699### ocf
700
701Updated OCF submodule to OCF v19.06
702
703Along with update, new cache mode 'write only' was added.
704
705New cache modes added to use via RPC, wi - write invalidate and wa - write around.
706
707New version of OCF provides fully asynchronous management API.
708
709## v19.07
710
711### ftl
712
713EXPERIMENTAL: Added ability to mirror writes to persistent write buffer cache
714to allow for recovery from dirty shutdown event.
715
716Added handling of Asynchronous Nand Management Events (ANM).
717
718### vmd
719
720EXPERIMENTAL: Added Intel Volume Management Device (VMD) driver. VMD is an integrated
721controller inside the CPU PCIe root complex. It enables virtual HBAs for the connected
722NVMe SSDs. `spdk_vmd_init()` enumerates NVMe SSDs behind VMD device and hook them into
723SPDK PCI subsystem. `spdk_nvme_probe()` or `spdk_nvme_connect()` can be used to connect
724NVMe driver to the device located at the given transport ID.
725
726To obtain transport ID of NVMe SSD behind VMD `spdk_lspci` can be used.
727
728Current implementation does not support hotplug.
729
730### blobfs
731
732Blobfs file asynchronous operations were added to public APIs.
733
734### util
735
736A new file API `spdk_posix_file_load` was added to load file content into a data buffer.
737
738New APIs `spdk_dif_ctx_set_data_offset`, `spdk_dif_verify_stream`,
739`spdk_dif_get_range_with_md`, `spdk_dif_get_length_with_md` have been added,
740and existing APIs `spdk_dif_ctx_init`, `spdk_dif_set_md_interleave_iovs`, and
741`spdk_dif_generate_stream` have been refined to insert or strip DIF by stream
742fasion with any alignment.
743
744New APIs `spdk_dif_ctx_set_remapped_init_ref_tag`, `spdk_dif_remap_ref_tag`,
745and `spdk_dix_remap_ref_tag` have been added to remap DIF reference tag.
746
747New APIs `spdk_dif_update_crc32c` and `spdk_dif_update_crc32c_stream` have been
748added to compute CRC-32C checksum for extended LBA payload.
749
750Bdevperf and bdevio applications now support starting tests with application specific
751RPCs. Please see helper Python scripts in their respective directories.
752This is a move towards simpler RPC-only configuration for all main
753and auxiliary applications.
754
755Legacy INI style configuration for SPDK applications will become deprecated in SPDK 19.10,
756and removed in SPDK 20.01. Please consider moving to JSON-RPC configuration files and/or
757RPC driven run-time configuration.
758
759### nvmf
760
761EXPERIMENTAL: A Fibre Channel transport that supports Broadcom HBAs has been
762added. This depends on the FC HBA driver at
763https://github.com/ecdufcdrvr/bcmufctdrvr. See [the documentation](https://spdk.io/doc/nvmf.html#nvmf_fc_transport)
764for more information.
765
766Persistent reservation emulation has been added to the NVMe-oF target. Persistent reservation
767state is stored in a JSON file on the local filesystem between target restart. To support this,
768an optional parameter to the RPC method `nvmf_subsystem_add_ns` called `--ptpl-file` was added.
769This allows the user to specify which file to store the persistent reservation state in.  Note
770that this is done per namespace.
771
772The c2h success optimization under which a command capsule response is not sent
773for reads is turned on by default. A config knob was added to allow disabling
774the optimization. This will mostly be used for integration testing with 5.0.x kernels
775while some compatibility fixes make their way down the pipeline for 5.1.x kernels.
776
777The sock priority setting of the TCP connection owned by the tcp transport is added. It is
778used to optimize the TCP connection performance under designated traffic classes. And the
779priority is used to differeniate the sock priority between SPDK NVMe-oF TCP target application
780and other TCP based applications.
781
782Shared receive queue can now be disabled even for NICs that support it using the
783`nvmf_create_transport` RPC method parameter `no_srq`. The actual use of a shared
784receive queue is predicated on hardware support when this flag is not used.
785
786spdk_nvmf_get_optimal_poll_group was added, which is used to return the optimal
787poll group for the qpair. And `ConnectionScheduler` configuration is added into the
788[Nvmf] section in etc/spdk/nvmf.conf.in to demonstrate how to configure the connection
789scheduling strategy among different spdk threads.
790
791Added infrastructure to retrieve global and per poll group NVMf statistics.
792
793DIF strip and insert is now supported for TCP transport. When it is enabled, DIF
794setting is not exposed to the NVMe-oF initiator, and DIF is attached into data
795for write I/O and stripped from data for read I/O.
796
797Added a field `dif_insert_or_strip` to struct spdk_nvmf_transport_opts, and
798updated the related rpc function nvmf_create_transport to make this
799configurable parameter available to users. The `dif_insert_or_strip` is relevant
800for TCP transport for now and used to configure the DIF strip and insert.
801
802Added infrastructure to retrieve NVMf transport statistics.
803
804### notify
805
806The function `spdk_notify_get_types()` and `spdk_notify_get_events()` were
807renamed to `spdk_notify_foreach_type()` and `spdk_notify_foreach_event()`,
808respectively. And update type name of callback accordingly.
809
810### bdev
811
812The format of the data returned by the get_bdevs_iostat RPC has changed to
813make it easier to parse.  It now returns an object with a "ticks" object
814and "bdevs" array with the per-bdev statistics.
815
816A new bdev module `delay` has been added which simulates a drive latency when placed
817on top of a Null bdev. This module is intended only for testing and can be created using
818the new RPC `bdev_delay_create`. That RPC takes the name of the underlying bdev as well
819as average and p99 latency arguments for both read and write operations. Average latency is
820defined as a value close to what you would expect a perf tool such as FIO to report back as
821the mean latency of all I/O submitted to the drive. p99 latency is defined as the value one
822would expect the drive to see the slowest 1% of I/O report. For underlying drives with already
823significant latency, the latency values provided to the drive will be additive. This should be
824taken into account if trying to achieve an artificial latency on top of an nvme drive or aio device.
825
826DIF reference tag remapping is now supported for partition type virtual bdev
827modules. When using partition type virtual bdevs, block address space is
828remapped during I/O processing and DIF reference tag is remapped accordingly.
829
830Added spdk_bdev_*_with_md() functions allowing for IO with metadata being transferred in
831separate buffer. To check support for separatate metadata, use spdk_bdev_is_md_separate().
832
833All bdevs now have a UUID. For devices whose backing hardware does not provide a UUID,
834one is automatically generated. Across runs of SPDK, bdevs whose UUID is automatically
835generated may change.
836
837A new virtual bdev module `compress` has been added to provide compression services on top of
838a thinly provisioned logical volume.  See documentation for complete details.
839
840### nvme
841
842Added an optional parameter `--io-queue-requests` to RPC `set_bdev_nvme_options`, which
843can be used to change the number of requests allocated for one NVMe I/O queue.  For
844very big I/O size, e.g. 128MiB, with this option user will not get an error due to
845limited requests in NVMe driver layer.
846
847Added spdk_nvme_ctrlr_get_transport_id() to get the transport ID from a
848previously attached controller.
849
850Nvme Opal library spdk_opal_cmd deprecated. Adding seperate command APIs.
851NVMe Opal library add support for activating locking SP which will make the transaction
852from "Manufactured-Inactive" state to "Manufactured" state. Upon successfully invoking
853of this method, lock and unlock features will be enabled.
854NVMe Opal library add support for locking/unlocking range and list locking range info.
855NVMe opal library add support for multiuser. Admin can enable user and add user to specific
856locking range and the user can lock/unlock his range.
857
858Added spdk_nvme_ctrlr_io_cmd_raw_no_payload_build() allowing a caller to pass
859a completely formed command to an NVMe submission queue (buffer addresses and all).
860This is supported on the PCIe transport only.
861
862Added spdk_nvme_get_ctrlr_registers() to return a pointer to the virtual address
863of the NVMe controller registers.  This is supported on the PCIe transport only.
864
865Added additional options to the spdk_nvme_ctrlr_alloc_qpair() option parameter
866structure to allow caller to override the virtual and optionally physical address
867of the submission and completion queue pair to be created.  This is supported on
868the PCIe transport only.
869
870Added `disable_error_logging` to struct spdk_nvme_ctrlr_opts, which disables
871logging of failed requests. By default logging is enabled.
872
873Added spdk_nvme_qpair_print_command(), spdk_nvme_qpair_print_completion() and
874spdk_nvme_cpl_get_status_string(). Allowing for easier display of error messages.
875
876Added support for NVMe Sanitize command.
877
878### env
879
880The parameter `free_space` has been added to spdk_ring_enqueue() to wait when
881the ring is almost full and resume when there is enough space available in
882the ring.
883
884A new API `spdk_mempool_lookup` has been added to lookup the memory pool created
885by the primary process.
886
887Added spdk_pci_get_first_device() and spdk_pci_get_next_device() to allow
888iterating over PCI devices detected by SPDK. Because of this, all SPDK APIs
889to attach/detach PCI devices are no longer thread safe. They are now meant to
890be called from only a single thread only, the same only that called spdk_env_init().
891This applies to the newly added APIs as well.
892
893### vpp
894
895SPDK now supports VPP version 19.04.2, up from VPP 18.01.
896
897VPP socket abstraction now uses VPP Session API, instead of VLC (VPP Communications Library).
898This allows for better control over sessions and queues.
899Please see VPP documentation for more details:
900[VPP Host Stack](https://wiki.fd.io/view/VPP/HostStack)
901
902### sock
903
904Add spdk_sock_get_optimal_sock_group(), which returns the optimal sock group for
905this socket. When a socket is created, it is often assigned to a sock group using
906spdk_sock_group_add_sock so that a set of sockets can be polled more efficiently.
907For some network devices, it is optimal to assign particular sockets to specific
908sock groups. This API is intended to provide the user with that information.
909
910spdk_sock_group_get_ctx() was added to return the context of the spdk_sock_group.
911spdk_sock_group_create() is updated to allow input the user provided ctx.
912spdk_sock_set_priority() is added to set the priority of the socket.
913
914### rpc
915
916Added thread_get_stats RPC method to retrieve existing statistics.
917
918Added nvmf_get_stats RPC method to retrieve NVMf susbsystem statistics.
919
920Response buffers for RPC requests are now always pre-allocated, which implies
921that all spdk_jsonrpc_begin_result() calls always succeed and return a valid
922buffer for JSON response. RPC calls no longer need to check if the buffer is
923non-NULL.
924
925Added SPDK_RPC_REGISTER_ALIAS_DEPRECATED to help with deprecation process when
926renaming existing RPC. First time a deprecated alias is used, it will print
927a warning message.
928
929RPC `get_rpc_methods` was renamed `rpc_get_methods`. The old name is still usable,
930but is now deprecated.
931
932### blobstore
933
934A snapshot can now be deleted if there is only a single clone on top of it.
935
936### build
937
938Preliminary support for cross compilation is now available. Targeting an older
939CPU on the same architecture using your native compiler can be accomplished by
940using the `--target-arch` option to `configure` as follows:
941
942~~~
943./configure --target-arch=broadwell
944~~~
945
946Additionally, some support for cross-compiling to other architectures has been
947added via the `--cross-prefix` argument to `configure`. To cross-compile, set CC
948and CXX to the cross compilers, then run configure as follows:
949
950~~~
951./configure --target-arch=aarm64 --cross-prefix=aarch64-linux-gnu
952~~~
953
954### vhost
955
956A security vulnerability has been identified and fixed in SPDK Vhost-SCSI target.
957A malicious client (e.g. a virtual machine) could send a carefully prepared,
958invalid I/O request to crash the entire SPDK process. All users of SPDK Vhost-SCSI
959target are strongly recommended to update. All SPDK versions < 19.07 are affected.
960
961By default, SPDK will now rely on upstream DPDK's rte_vhost instead of its fork
962located inside SPDK repo. The internal fork is still kept around to support older
963DPDK versions, but is considered legacy and will be eventually removed.
964
965`configure` will now automatically use the upstream rte_vhost if the used DPDK
966version is >= 19.05.
967
968spdk_vhost_init() is now asynchronous and accepts a completion callback.
969
970### iscsi target
971
972A security vulnerability has been identified and fixed in SPDK iSCSI target.
973A malicious client (e.g. an iSCSI initiator) could send a carefully prepared,
974invalid I/O request to crash the entire SPDK process. All users of SPDK iSCSI
975target are strongly recommended to update. All SPDK versions < 19.07 are affected.
976
977### thread
978
979Exposed spdk_set_thread() in order for applications to associate
980with SPDK thread when necessary.
981
982Added spdk_thread_destroy() to allow framework polling the thread to
983release resources associated with that thread.
984
985## v19.04
986
987### nvme
988
989Added asynchronous probe support. New APIs spdk_nvme_probe_async(),
990spdk_nvme_connect_async() and spdk_nvme_probe_poll_async() were added to enable
991this feature. spdk_nvme_probe_async() and spdk_nvme_connect_async() return a
992context associated with the specified controllers. Users then call
993spdk_nvme_probe_poll_async() until it returns 0, indicating that the operation
994completed.
995
996A new qpair creation option, delay_pcie_doorbell, was added. This can be passed
997to spdk_nvme_alloc_io_qpair(). This makes the I/O submission functions, such as
998spdk_nvme_ns_writev(), skip ringing the submission queue doorbell. Instead the
999doorbell will be rung as necessary inside spdk_nvme_qpair_process_completions().
1000This can result in significantly fewer MMIO writes to the doorbell register
1001under heavy load, greatly improving performance.
1002
1003spdk_nvme_ctrlr_get_regs_cmbsz() was added to report the size of the controller
1004memory buffer, if available.
1005
1006spdk_nvme_ctrlr_get_flags() was added to return controller feature
1007flags. Two flags are currently tracked:
1008SPDK_NVME_CTRLR_SGL_SUPPORTED
1009SPDK_NVME_CTRLR_SECURITY_SEND_RECV_SUPPORTED
1010
1011The NVMe hotplug poller is now able to detach devices hot-removed from the system
1012via `/sys/bus/pci/devices/<bdf>/remove` and `/sys/bus/pci/devices/<bdf>/driver/unbind`.
1013
1014Opal support was added for scan, take ownership, revert TPer, and dumping device
1015info. The nvme_manage tool can be used to perform these operations. The public
1016API functions are spdk_nvme_ctrlr_security_receive() and
1017spdk_nvme_ctrlr_security_send(). This module should be considered experimental
1018pending additional features and tests.
1019
1020The NVMe-oF initiator is now able to transfer IO whose size is more than 128KiB
1021if the corresponding NVMe-oF target allows.
1022
1023### raid
1024
1025Added new strip_size_kb rpc param on create to replace the more ambiguous
1026strip_size. The strip_size rpc param is deprecated.
1027
1028Changed the raid bdev product_name from "Pooled Device" to "Raid Volume"
1029
1030### thread
1031
1032Added spdk_thread_has_pollers() function to verify if there are any registered
1033pollers to be run on the thread. Added spdk_thread_is_idle() function to check
1034if there are any scheduled operations to be performed on the thread at given
1035time.
1036
1037spdk_thread_create() now takes an optional CPU affinity mask that is passed to
1038the scheduler.
1039
1040spdk_thread_lib_init() now takes an optional context size. For each thread
1041created, an additional region of memory of this size will be allocated. A
1042pointer to this region of memory can be obtained by calling
1043spdk_thread_get_ctx(). The inverse operation is also available via
1044spdk_thread_get_from_ctx().
1045
1046spdk_thread_poll() now optionally accepts the current time, in ticks. This can
1047be used to avoid some calls to spdk_get_ticks() internally.
1048
1049spdk_app_start() now only accepts a single context argument.
1050
1051### bdev
1052
1053An new API `spdk_bdev_get_data_block_size` has been added to get size of data
1054block except for metadata.
1055
1056spdk_vbdev_register() has been deprecated.  spdk_bdev_register() should be used
1057instead.
1058
1059A mechanism for acquiring and releasing data buffers from bdev modules, used
1060to perform zero copy operations, was added.
1061
1062New APIs spdk_bdev_get_md_size(), spdk_bdev_is_md_interleaved(), spdk_bdev_get_dif_type(),
1063spdk_bdev_is_dif_head_of_md(), and spdk_bdev_is_dif_check_enabled() have been
1064added to get metadata and DIF settings.
1065
1066Bdevs claimed by the `examine_config` callback will be now further examined in the
1067`examine_disk` callback.
1068
1069spdk_bdev_io_get_io_channel() was added as a convenient way to get an io_channel
1070from a bdev_io.
1071
1072### ocf
1073
1074Updated OCF submodule to OCF v19.3.2
1075
1076Added support for many-to-one configuration for OCF bdev.
1077Multiple core devices can now be cached on single cache device.
1078
1079Added persistent metadata support, allowing to restore cache state after shutdown.
1080During start of SPDK application, the devices are examined and if OCF metadata
1081is present - appropriate OCF bdevs will be recreated.
1082
1083Added Write-Back mode support. In this mode, data is first written to
1084caching device and periodically synchronized to the core devices.
1085Dirty data is saved as persistent metadata on cache device,
1086allowing for safe restore during application restart.
1087For more details please see OCF documentation:
1088[OpenCAS cache configuration](https://open-cas.github.io/cache_configuration.html)
1089
1090### NVMe-oF Target
1091
1092Support for per-device shared receive queues in the RDMA transport has been added.
1093It is enabled by default for any device that supports it.
1094
1095The size of a shared receive queue is defined by transport configuration file parameter
1096`MaxSRQDepth` and `nvmf_create_transport` RPC method parameter `max_srq_depth`.
1097Default size is 4096.
1098
1099Add model number as parameter to construct_nvmf_subsystem (-d option),
1100rather than using hardcoded define.
1101
1102DIF passthrough feature has been added. DIF setting of the allocated bdevs is
1103exposed to the NVMe-oF initiator and data with DIF from the NVMe-oF initiator is
1104passed through to the allocated bdevs.
1105
1106### env
1107
1108The `phys_addr` parameter in spdk_malloc() and spdk_zmalloc() has been deprecated.
1109For retrieving physical addresses, spdk_vtophys() should be used instead.
1110
1111spdk_realloc() has been added to reallocate DMA/shared memory.
1112
1113spdk_pci_device_is_removed() has been added to let the upper-layer SPDK drivers know
1114that device has a pending external hotremove request.
1115
1116spdk_env_fini() and spdk_env_dpdk_post_fini() were added to release any resources
1117allocated by spdk_env_init() or spdk_env_dpdk_post_init() respectively. It is expected
1118that common usage of those functions is to call them just before terminating the process.
1119
1120Added spdk_iommu_is_enabled() to report if SPDK application is using IOMMU for DMA.
1121
1122### DPDK
1123
1124Dropped support for DPDK 17.07 and earlier, which SPDK won't even compile with right now.
1125
1126Updated DPDK submodule to DPDK 19.02.
1127
1128### rpc
1129
1130New `get_spdk_version` RPC method is introduced to get version info of the running SPDK application.
1131
1132The `start_nbd_disk` RPC method now take nbd_device as an optional parameter. If nbd_device
1133is specified, use that specified nbd device. If it's not specified, pick available one.
1134
1135### iSCSI target
1136
1137DIF strip and insert is now supported. DIF settings are not exposed to the iSCSI initiator.
1138DIF is attached into data for write I/O and stripped from data for read I/O.
1139
1140### vhost
1141
1142Added experimental support for running with the external, upstream rte_vhost library.
1143This can be enabled by configuring SPDK with an `--without-internal-vhost-lib` flag.
1144The minimum supported rte_vhost version (DPDK version) is 19.05-rc1.
1145
1146As a result of fuzz testing, a lot of data races in vhost-scsi LUN hotplug path were identified and
1147fixed. Those data races could have potentially resulted in SPDK crashes, RPC hangs, or memory leaks
1148if Vhost-SCSI LUN hotplug RPCs were executed while connected VMs were in the middle of restarting.
1149
1150The SCSI target id in `add_vhost_scsi_lun` RPC is now optional. If `-1` is passed, the first
1151unoccupied target id will be used.
1152
1153### AIO
1154
1155AIO bdev module can now reap I/O completions directly from userspace, significantly improving
1156the overall performance.
1157
1158### blobfs
1159
1160Synchronous IO operations no longer use spdk_io_channel, but instead use
1161spdk_fs_thread_ctx. The behavior is otherwise identical.
1162
1163### OCF
1164
1165Added support for caching multiple bdevs using a single bdev as a cache.
1166
1167### notify
1168
1169Added the notify library that provides a high performance local event bus
1170between libraries. Example usage was added to bdev module, which reports
1171notifications for added and removed bdevs via RPC.
1172
1173### sock
1174
1175Added new API spdk_sock_readv() to the sock library for performing vectored
1176reads.
1177
1178### event
1179
1180The function spdk_subsystem_init() no longer requires spdk_event as an argument.
1181
1182Changed API of spdk_subsystem_config_json() to no longer be asynchronous.
1183
1184### io_uring
1185
1186A bdev module that issues I/O to kernel block devices using the new io_uring Linux kernel
1187API was added. This module requires liburing.
1188
1189### build
1190
1191Options to easily compile with profile guided optimization have been added to
1192`configure`. To use profile guided optimization with SPDK, run
1193`./configure --with-pgo-capture`, build SPDK, then run a workload of your
1194choosing. Then, simply run `./configure --with-pgo-enable` and recompile to
1195build using the generated profile data. Profile guided optimization can yield
1196very large performance improvements, especially on GCC 8 and clang 7. This may
1197be combined with link time optimization which has been available under the
1198`--enable-lto` configure option for several releases.
1199
1200### compression bdev/reduce library
1201
1202Added "reduce" block compression scheme based on using SSDs for storing
1203compressed blocks of storage and presistent memory for metadata. Please see
1204[compression](https://spdk.io/doc/bdev.html) for more details.
1205
1206## v19.01
1207
1208### ocf bdev
1209
1210New virtual bdev module based on [Open CAS Framework](https://open-cas.github.io/) has been added.
1211This module allows for the use of one bdev to act as a high performance cache in front of another bdev.
1212Please see [documentation](https://spdk.io/doc/bdev.html#bdev_config_cas) for more details.
1213Only write through mode is currently supported and this feature is considered experimental.
1214
1215### event framework
1216
1217For `spdk_app_parse_args`, add return value to the callback which parses application
1218specific command line parameters to protect SPDK applications from crashing by invalid
1219values from user input.
1220
1221By default, all SPDK applications will now reserve all hugepages at runtime. The pre-reserved
1222memory size can be still set with `-s` or `--mem-size` option, although the default value
1223was reduced down to 0.
1224
1225A custom hugetlbfs directory can now be specified via spdk_app_opts.
1226This can be used to configure hugepages with different sizes, a different size limit,
1227or different access permissions than the system's default hugepage pool.
1228SPDK applications can specify a custom hugetlbfs mount with the `--huge-dir` option.
1229
1230### environment
1231
1232spdk_vtophys() has been refactored to accept length of the translated region as a new
1233parameter. The function will now update that parameter with the largest possible value
1234for which the memory is contiguous in the physical memory address space.
1235
1236The following functions were removed:
1237
1238 - spdk_pci_nvme_device_attach()
1239 - spdk_pci_nvme_enumerate()
1240 - spdk_pci_ioat_device_attach()
1241 - spdk_pci_ioat_enumerate()
1242 - spdk_pci_virtio_device_attach()
1243 - spdk_pci_virtio_enumerate()
1244
1245They were replaced with generic spdk_pci_device_attach() and spdk_pci_enumerate() which
1246require a new spdk_pci_driver object to be provided. It can be one of the following:
1247
1248 - spdk_pci_nvme_get_driver()
1249 - spdk_pci_ioat_get_driver()
1250 - spdk_pci_virtio_get_driver()
1251
1252spdk_pci_hook_device() and spdk_pci_unhook_device() were added. Those allow adding a virtual
1253spdk_pci_device into the SPDK PCI subsystem. A virtual device calls provided callbacks for
1254each BAR mapping request or PCI config access. It's attachable with spdk_pci_device_attach()
1255or spdk_pci_enumerate() like any other device.
1256
1257A new spdk_pause() function was added to pause CPU execution for an implementation specific
1258amount of time. Quoting from DPDK function this is based on: "This call is intended for
1259tight loops which poll a shared resource or wait for an event. A short pause within the loop
1260may reduce the power consumption."
1261
1262A new public header file env_dpdk.h has been introduced, and function spdk_env_dpdk_post_init
1263is added into it. If user is using DPDK, and already called rte_eal_init, then include
1264include/spdk/env_dpdk.h, and call spdk_env_dpdk_post_init() instead of spdk_env_init.
1265
1266ISA-L has been added as an SPDK submodule.  ISA-L is enabled by default on x86 architecture
1267to accelerate algorithms such as CRC for iSCSI and NVMe-oF.  Users may still disable ISA-L
1268by explicitly passing --without-isal to the configure script.
1269
1270### util
1271
1272A new uuid API `spdk_uuid_copy` was added to make a copy of the source uuid.
1273
1274An new parameter `init_crc` representing the initial CRC value was added to
1275`spdk_crc16_t10dif`. The parameter can be used to calculate a CRC value spanning
1276multiple separate buffers.
1277
1278New DIF APIs were added to generate and verify DIF by byte granularity for both DIF and DIX
1279formats. Among them, DIF with copy APIs will be usable to emulate DIF operations such as DIF
1280insert and strip.
1281
1282Added `spdk_strtol` and `spdk_strtoll` to provide additional error checking around `strtol`
1283and `strtoll`.
1284
1285Added `spdk_sprintf_append_realloc` and `spdk_vsprintf_append_realloc` for appending a string
1286with automatic buffer re-allocation.
1287
1288### nvme
1289
1290Wrapper functions spdk_nvme_ctrlr_security_send() and spdk_nvme_ctrlr_security_receive() are
1291introduced to support further security protocol development.
1292
1293admin_timeout_ms was added to NVMe controller initialization options, users
1294can change the default value when probing a controller.
1295
1296Add two new fields "header_digest" and "data_digest" in struct spdk_nvme_ctrlr_opts,
1297it will be used to enable the digest support for the NVMe/TCP transport.
1298
1299Add a new TCP/IP transport(located in lib/nvme/nvme_tcp.c) in nvme driver. With
1300this new transport, it can be used to connect the NVMe-oF target with the
1301same TCP/IP support.
1302
1303Added API, spdk_nvme_ctrlr_is_discovery(), to indicate whether the ctrlr
1304arg refers to a Discovery Controller or not.
1305
1306Added an API function `spdk_nvme_host_id_parse` and corresponding object `spdk_nvme_host_id`
1307for parsing host address and host service ID arguments on a per connection basis.
1308
1309The RPC `construct_nvme_bdev` now allows a user to specify a source address and service id for the host to
1310use when connecting to the controller backing the NVMe bdev.
1311
1312### NVMe-oF Target
1313
1314The `spdk_nvmf_tgt_opts` struct has been deprecated in favor of `spdk_nvmf_transport_opts`.
1315Users will no longer be able to specify target wide I/O parameters. `spdk_nvmf_tgt_listen`
1316will also no longer implicitly initialize a transport with the default target options (since
1317there are none). Instead, a user must manually instantiate the transport with `spdk_nvmf_transport_create`
1318prior to calling `spdk_nvmf_tgt_listen`.
1319
1320Related to the previous change, the rpc `set_nvmf_target_options` has been renamed to
1321`set_nvmf_target_max_subsystems` to indicate that this is the only target option available for the user to edit.
1322
1323Added fields `num_shared_buffers` and `buf_cache_size` in struct spdk_nvmf_transport_opts,
1324and also updated the related rpc function nvmf_create_transport, to make this
1325configurable parameter available to users. The `num_shared_buffers` is used to
1326configure the shared buffer numbers of the transport used by RDMA or TCP transport.
1327`buf_cache_size` configures number of shared buffers to cache per poll group.
1328
1329### nvmf
1330
1331Add a new TCP/IP transport (located in lib/nvmf/tcp.c). With this tranport,
1332the SPDK NVMe-oF target can have a new transport, and can serve the NVMe-oF
1333protocol via TCP/IP from the host.
1334
1335Added optional mechanism to modify the RDMA transport's behavior when creating protection domains and registering memory.
1336By default, the RDMA transport will use the ibverbs library to create protection domains and register memory.
1337Using `spdk_nvme_rdma_init_hooks` will subvert that and use an existing registration.
1338
1339### bdev
1340
1341Added `enable_bdev_histogram` and `get_bdev_histogram` RPC commands to allow gathering latency data for specified bdev.
1342Please see [documentation](https://spdk.io/doc/bdev.html#rpc_bdev_histogram) for more details.
1343
1344Added `required_alignment` field to `spdk_bdev`, that specifies an alignment requirement for data buffers associated with an spdk_bdev_io.
1345Bdev layer will automatically double buffer any spdk_bdev_io that violates this alignment, before the spdk_bdev_io is submitted to the bdev module.
1346
1347On shutdown, bdev unregister now proceeds in top-down fashion, with
1348claimed bdevs skipped (these will be unregistered later, when virtual
1349bdev built on top of the respective base bdev unclaims it). This
1350allows virtual bdevs to be shut down cleanly as opposed to the
1351previous behavior that didn't differentiate between hotremove and
1352planned shutdown.
1353
1354The `delete_bdev` RPC is now deprecated. Users should instead use the specific deletion RPC
1355for the bdev type to be removed (i.e. delete_malloc_bdev).
1356
1357Added support for separate bandwidth rate limits for read and write to QoS in bdev layer.
1358
1359Bdev I/O statistics now track unmap opertations.
1360
1361### logical volumes
1362
1363Logical volume bdev can now be marked as read only using `set_read_only_lvol_bdev` RPC.
1364This allows for basing clones on top of lvol_bdev without first creating a snapshot.
1365
1366Added option to change method for data erasure when deleting lvol or resizing down.
1367Default of unmapping clusters can now be changed to writing zeroes or no operation.
1368
1369Added option to change method for erasing data region on lvol store creation.
1370Default of unmapping can now be changed to writing zeroes or no operation.
1371
1372### log
1373
1374"trace flags" are now referred to as "log flags" in the SPDK log API.  The
1375set_trace_flag, clear_trace_flag and get_trace_flags RPCs are now deprecated,
1376and set_log_flag, clear_log_flag and get_log_flags RPCs have been added.
1377
1378### trace
1379
1380New `trace_record` application was added. It can be used to poll spdk trace shm file and
1381append any new trace entries into another specified file. This can help retain those entries
1382that would otherwise be overwritten in the shm file. See
1383[Capturing sufficient trace events](https://spdk.io/doc/nvmf_tgt_tracepoints.html#capture_trace_events)
1384for more details.
1385
1386Number of trace entries in circular buffer per lcore can now be assigned by starting SPDK app
1387with argument "--num-trace-entries <NUM>" provided.
1388
1389New `get_tpoint_group_mask` RPC was added to get current tpoint_group_mask, and
1390each tpoint group status.
1391New `enable_tpoint_group` and `disable_tpoint_group` RPC were added to enable or
1392disable a specific tpoint group.
1393
1394### ftl
1395
1396EXPERIMENTAL: Added basic flash translation layer module allowing for using Open Channel SSDs as
1397block devices. The module is split into the library (located in lib/ftl) and bdev_ftl
1398(lib/bdev/ftl). See the [documentation](https://spdk.io/doc/ftl.html) for more details.
1399
1400### vhost
1401
1402A security vulnerability has been identified and fixed in the SPDK vhost target.  A malicious
1403vhost client (i.e. virtual machine) could carefully construct a circular descriptor chain which
1404would result in a partial denial of service in the SPDK vhost target.  These types of descriptor
1405chains are now properly detected by the vhost target.  All SPDK vhost users serving untrusted
1406vhost clients are strongly recommended to upgrade. (Reported by Dima Stepanov and Evgeny
1407Yakovlev.)
1408
1409Vhost SCSI and Vhost Block devices can now accept multiple connections on the same socket file.
1410Each connection (internally called a vhost session) will have access to the same storage, but
1411will use different virtqueues, different features and possibly different memory.
1412
1413### vhost scsi
1414
1415SCSI target hotremove can now be performed even without the VIRTIO_SCSI_F_HOTPLUG feature negotiated.
1416Regardless of VIRTIO_SCSI_F_HOTPLUG support, the hotremoval will be still reported through SCSI sense codes.
1417
1418### DPDK
1419
1420DPDK submodule was updated to DPDK 18.11. Note that SPDK does not fully leverage the new
1421multi-process device hotplug yet and continues to work the same way it always did.
1422
1423Dropped support for DPDK 16.07 and earlier, which SPDK won't even compile with right now.
1424
1425### RPC
1426
1427The following RPC commands deprecated in the previous release are now removed:
1428
1429 - construct_virtio_user_scsi_bdev
1430 - construct_virtio_pci_scsi_bdev
1431 - construct_virtio_user_blk_bdev
1432 - construct_virtio_pci_blk_bdev
1433 - remove_virtio_scsi_bdev
1434 - construct_nvmf_subsystem
1435
1436### Miscellaneous
1437
1438The configure options `--with-raid` and `--without-raid` that were deprecated in the previous
1439release are now removed.
1440
1441### nbd
1442
1443Starting nbd using `spdk_nbd_start` is now performed asynchronously.
1444
1445### net framework
1446
1447Net framework initialization and finish is now done asynchronously.
1448
1449### rpc
1450
1451Added `spdk_rpc_is_method_allowed` function for checking whether method is permitted in a given state.
1452Added `spdk_rpc_get_state` to check current state of RPC server.
1453RPC `wait_subsystem_init` has been added to allow clients to block untill all subsystems are initialized.
1454
1455### json rpc
1456
1457JSON RPC client is now running in non-blocking mode. Requests are sent and received during spdk_jsonrpc_client_poll.
1458JSON RPC server can now recieve a callback on connection termination or server shutdown using `spdk_jsonrpc_conn_add_close_cb`
1459and `spdk_jsonrpc_conn_del_close_cb`.
1460
1461## v18.10
1462
1463### nvme
1464
1465spdk_nvme_ctrlr_cmd_security_send() and spdk_nvme_ctrlr_cmd_security_receive()
1466were added to support sending or receiving security protocol data to or from
1467nvme controller.
1468
1469spdk_nvme_ns_get_extended_sector_size() was added.  This function includes
1470the metadata size per sector (if any).  spdk_nvme_ns_get_sector_size() still
1471returns only the data size per sector, not including metadata.
1472
1473New `send_nvme_cmd` RPC was added to allow sending NVMe commands directly to NVMe controller.
1474See the [send_nvme_cmd](http://spdk.io/doc/jsonrpc.html#rpc_send_nvme_cmd) documentation
1475for more details.
1476
1477### Build System
1478
1479New `configure` options, `--with-shared` and `--without-shared`
1480[default], provide the capability to build, or not, SPDK shared libraries.
1481This includes the single SPDK shared lib encompassing all of the SPDK
1482static libs as well as individual SPDK shared libs corresponding to
1483each of the SPDK static ones.  Although the production of the shared
1484libs conforms with conventional version naming practices, such naming
1485does not at this time confer any SPDK ABI compatibility claims.
1486
1487### bdev
1488
1489spdk_bdev_alias_del_all() was added to delete all alias from block device.
1490
1491A new virtual bdev module has been added to perform at rest data encryption using the DPDK CryptoDev
1492Framework.  The module initially uses a software AESNI CBC cipher with experimental support for the
1493Intel QAT hardware accelerator also currently implemented with support for CBC cipher. Future work
1494may include additional ciphers as well as consideration for authentication.
1495
1496The RAID virtual bdev module is now always enabled by default.  The configure --with-raid and
1497--without-raid options are now ignored and deprecated and will be removed in the next release.
1498
1499Enforcement of bandwidth limits for quality of service (QoS) has been added to the bdev layer.
1500See the new [set_bdev_qos_limit](http://www.spdk.io/doc/jsonrpc.html#rpc_set_bdev_qos_limit)
1501documentation for more details. The previous set_bdev_qos_limit_iops RPC method introduced at
150218.04 release has been deprecated. The new set_bdev_qos_limit RPC method can support both
1503bandwidth and IOPS limits.
1504
1505spdk_bdev_config_json() and corresponding `get_bdevs_config` RPC was removed.
1506
1507### Environment Abstraction Layer and Event Framework
1508
1509The size parameter of spdk_mem_map_translate is now a pointer. This allows the
1510function to report back the actual size of the translation relative to the original
1511request made by the user.
1512
1513A new structure spdk_mem_map_ops has been introduced to hold memory map related
1514callbacks. This structure is now passed as the second argument of spdk_mem_map_alloc
1515in lieu of the notify callback.
1516
1517### DPDK 18.08
1518
1519The DPDK submodule has been updated to the DPDK 18.08 release. SPDK will now automatically
1520utilize DPDK's dynamic memory management with DPDK versions >= 18.05.1.
1521
1522Hugepages can be still reserved with `[-s|--mem-size <size>]` option at application startup,
1523but once we use them all up, instead of failing user allocations with -ENOMEM, we'll try
1524to dynamically reserve even more. This allows starting SPDK with `--mem-size 0` and using
1525only as many hugepages as it is really needed.
1526
1527Due to this change, the memory buffers returned by `spdk_*malloc()` are no longer guaranteed
1528to be physically contiguous.
1529
1530### I/OAT
1531
1532I/OAT driver can now reinitialize I/OAT channels after encountering DMA errors.
1533
1534### iscsi target
1535
1536Parameter names of `set_iscsi_options` and `get_iscsi_global_params` RPC
1537method for CHAP authentication in discovery sessions have been changed to
1538align with `construct_target_node` RPC method. Old names are still usable
1539but will be removed in future release.
1540
1541`set_iscsi_discovery_auth` and `set_iscsi_target_node_auth` RPC methods have
1542been added to set CHAP authentication for discovery sessions and existing
1543target nodes, respectively.
1544
1545The SPDK iSCSI target supports an AuthFile which can be used to load CHAP
1546shared secrets when the iSCSI target starts. SPDK previously provided a
1547default location for this file (`/usr/local/etc/spdk/auth.conf`) if none was
1548specified. This default has been removed. Users must now explicitly specify
1549the location of this file to load CHAP shared secrets from a file, or use
1550the related iSCSI RPC methods to add them at runtime.
1551
1552### iscsi initiator
1553
1554The SPDK iSCSI initiator is no longer considered experimental and becomes
1555a first-class citizen among bdev modules. The basic usage has been briefly
1556described in the bdev user guide: [iSCSI bdev](https://spdk.io/doc/bdev.html#bdev_config_iscsi)
1557
1558### Miscellaneous
1559
1560The SPDK application framework can now parse long name command line parameters.
1561Most single-character parameters have a long name equivalent now. See the
1562[Command Line Parameters](https://spdk.io/doc/app_overview.html) documentation
1563for details or use the `--help` command line parameter to list all available
1564params.
1565
1566bdevperf `-s` param (io size) was renamed to `-o` as `-s` had been already
1567used by existing apps for memory size.
1568
1569bdevio can now accept all SPDK command line parameters. The config now has to
1570be provided with `-c` or `--config` param.
1571
1572The following ioat/perf and nvme/perf parameters were renamed as well:
1573 `-s` (io size) to `-o`
1574 `-d` (mem size) to `-s`
1575
1576The ReactorMask config file parameter has been deprecated.  Users should
1577use the -m or --cpumask command line option to specify the CPU core mask
1578for the application.
1579
1580Default config file pathnames have been removed from iscsi_tgt, nvmf_tgt
1581and vhost.  Config file pathnames may now only be specified using the
1582-c command line option.
1583
1584Users may no longer set DPDK_DIR in their environment to specify the
1585location of the DPDK installation used to build SPDK.  Using DPDK_DIR
1586has not been the documented nor recommended way to specify the DPDK
1587location for several releases, but removing it ensures no unexpected
1588surprises for users who may have DPDK_DIR defined for other reasons.
1589Users should just use the "configure" script to specify the DPDK
1590location before building SPDK.
1591
1592Although we know that many developers still use Python 2 we are officially
1593switching to Python3 with requirement that all new code must be valid also
1594for Python 2 up to the EOL which is year 2020.
1595
1596Invoking interpreter explicitly is forbidden for executable scripts. There
1597is no need to use syntax like "python ./scripts/rpc.py". All executable
1598scripts must contain proper shebang pointing to the right interpreter.
1599Scripts without shebang musn't be executable.
1600
1601A Python script has been added to enable conversion of old INI config file
1602to new JSON-RPC config file format. This script can be found at
1603scripts/config_converter.py. Example how this script can be used:
1604~~~{.sh}
1605cat old_format.ini | scripts/config_converter.py > new_json_format.json
1606~~~
1607
1608### Sock
1609
1610Two additional parameters were added to spdk_sock_get_addr() for the server
1611port and client port. These parameters are named "sport" and "cport"
1612respectively.
1613
1614### Virtio
1615
1616The following RPC commands have been deprecated:
1617
1618 - construct_virtio_user_scsi_bdev
1619 - construct_virtio_pci_scsi_bdev
1620 - construct_virtio_user_blk_bdev
1621 - construct_virtio_pci_blk_bdev
1622 - remove_virtio_scsi_bdev
1623
1624The `construct_virtio_*` ones were replaced with a single `construct_virtio_dev`
1625command that can create any type of Virtio bdev(s). `remove_virtio_scsi_bdev`
1626was replaced with `remove_virtio_bdev` that can delete both Virtio Block and SCSI
1627devices.
1628
1629### Blobfs
1630
1631spdk_file_get_id() returning unique ID for the file was added.
1632
1633### JSON
1634
1635Added jsonrpc-client C library intended for issuing RPC commands from applications.
1636
1637Added API enabling iteration over JSON object:
1638
1639 - spdk_json_find()
1640 - spdk_json_find_string()
1641 - spdk_json_find_array()
1642 - spdk_json_object_first()
1643 - spdk_json_array_first()
1644 - spdk_json_next()
1645
1646### Blobstore
1647
1648Blobstore I/O operations are now based on io_units, instead of blobstore page size.
1649The io_unit size is now the same as the underlying block device's block size.
1650Logical volumes built on a block device with 512B block size can now be used as boot devices
1651in QEMU.
1652
1653### SPDKCLI
1654
1655The SPDKCLI interactive command tool for managing SPDK is no longer considered experimental.
1656Support for the iSCSI and NVMe-oF targets has been added.
1657
1658## v18.07
1659
1660### bdev
1661
1662A new public header file bdev_module.h has been introduced to facilitate the
1663development of new bdev modules. This header includes an interface for the
1664spdk_bdev_part and spdk_bdev_part_base objects to enable the creation of
1665multiple virtual bdevs on top of a single base bdev and should act as the
1666primary API for module authors.
1667
1668spdk_bdev_get_opts() and spdk_bdev_set_opts() were added to set bdev-wide
1669options.
1670
1671A mechanism for handling out of memory condition errors (ENOMEM) returned from
1672I/O submission requests at the bdev layer has been added. See
1673spdk_bdev_queue_io_wait().
1674
1675The spdk_bdev_get_io_stat() function now returns cumulative totals instead of
1676resetting on each call. This allows multiple callers to query I/O statistics
1677without conflicting with each other. Existing users will need to adjust their
1678code to record the previous I/O statistics to calculate the delta between calls.
1679
1680I/O queue depth tracking and samples options have been added. See
1681spdk_bdev_get_qd(), spdk_bdev_get_qd_sampling_period(), and
1682spdk_bdev_set_qd_sampling_period().
1683
1684### RAID module
1685
1686A new bdev module called "raid" has been added as experimental module which
1687aggregates underlying NVMe bdevs and exposes a single raid bdev. Please note
1688that vhost will not work with this module because it does not yet have support
1689for multi-element io vectors.
1690
1691### Log
1692
1693The debug log component flag available on several SPDK applications has been
1694renamed from `-t` to `-L` to prevent confusion with tracepoints and to allow the
1695option to be added to tools that already use `-t` to mean something else.
1696
1697### Blobstore
1698
1699A new function, spdk_bs_dump(), has been added that dumps all of the contents of
1700a blobstore to a file pointer. This includes the metadata and is very useful for
1701debugging.
1702
1703Two new operations have been added for thin-provisioned blobs.
1704spdk_bs_inflate_blob() will allocate clusters for all thinly provisioned regions
1705of the blob and populate them with the correct data by reading from the backing
1706blob(s). spdk_bs_blob_decouple_parent() works similarly, but will only allocate
1707clusters that correspond to data in the blob's immediate parent. Clusters
1708allocated to grandparents or that aren't allocated at all will remain
1709thin-provisioned.
1710
1711### BlobFS
1712
1713Changed the return type of spdk_file_truncate() from void to int to allow the
1714propagation of `ENOMEM` errors.
1715
1716### NVMe Driver
1717
1718The new API functions spdk_nvme_qpair_add_cmd_error_injection() and
1719spdk_nvme_qpair_remove_cmd_error_injection() have been added for NVMe error
1720emulation. Users can set a specified command to fail with a particular error
1721status.
1722
1723Changed the name `timeout_sec` parameter to `timeout_us` in
1724spdk_nvme_ctrlr_register_timeout_callback(), and also changed the type from
1725uint32_t to uint64_t. This will give users more fine-grained control over the
1726timeout period.
1727
1728Basic support for Open Channel SSDs was added. See nvme_ocssd.h
1729
1730### NVMe Over Fabrics
1731
1732The spdk_nvmf_tgt_destroy() function is now asynchronous and takes a callback
1733as a parameter.
1734
1735spdk_nvmf_qpair_disconnect() was added to allow the user to disconnect qpairs.
1736
1737spdk_nvmf_subsystem_get_max_namespaces() was added to query the maximum allowed
1738number of namespaces for a given subsystem.
1739
1740### Build System
1741
1742The build system now generates a combined shared library (libspdk.so) that may
1743be used in place of the individual static libraries (libspdk_*.a). The combined
1744library includes all components of SPDK and is intended to make linking against
1745SPDK easier. The static libraries are also still provided for users that prefer
1746to link only the minimal set of components required.
1747
1748### git pre-commit and pre-push hooks
1749
1750The pre-commit hook will run `scripts/check_format.sh` and verify there are no
1751formating errors before allowing `git commit` to run. The pre-push hook runs
1752`make CONFIG_WERROR=y` with and without `CONFIG_DEBUG=y` using both the gcc and
1753clang compiler before allowing `git push` to run. Following each DEBUG build
1754`test/unit/unittest.sh` is run and verified. Results are recorded in the
1755`make.log` file.
1756
1757To enable type: 'git config core.hooksPath .githooks'. To override after
1758configuration use the `git --no-verify` flag.
1759
1760### RPC
1761
1762The `start_nbd_disk` RPC method now returns the path to the kernel NBD device node
1763rather than always returning `true`.
1764
1765### DPDK 18.05
1766
1767The DPDK submodule has been rebased on the DPDK 18.05 release.  DPDK 18.05 supports
1768dynamic memory allocation, but due to some issues found after the DPDK 18.05 release,
1769that support is not enabled for SPDK 18.07.  Therefore, SPDK 18.07 will continue to use
1770the legacy memory allocation model.  The plan is to enable dynamic memory allocation
1771after the DPDK 18.08 release which should fix these issues.
1772
1773### Environment Abstraction Layer and Event Framework
1774
1775The spdk_mem_map_translate() function now takes a size parameter to indicate the size of
1776the memory region.  This can be used by environment implementations to validate the
1777requested translation.
1778
1779The I/O Channel implementation has been moved to its own library - lib/thread. The
1780public API that was previously in spdk/io_channel.h is now in spdk/thread.h The
1781file spdk/io_channel.h remains and includes spdk/thread.h.
1782
1783spdk_reactor_get_tsc_stats was added to return interesting statistics for each
1784reactor.
1785
1786### IOAT
1787
1788IOAT for copy engine is disabled by default. It can be enabled by specifying the Enable
1789option with "Yes" in `[Ioat]` section of the configuration file. The Disable option is
1790now deprecated and will be removed in a future release.
1791
1792## v18.04: Logical Volume Snapshot/Clone, iSCSI Initiator, Bdev QoS, VPP Userspace TCP/IP
1793
1794### vhost
1795
1796The SPDK vhost-scsi, vhost-blk and vhost-nvme applications have fixes to address the
1797DPDK rte_vhost vulnerability [CVE-2018-1059](http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-1059).
1798Please see this [security advisory](https://access.redhat.com/security/cve/cve-2018-1059)
1799for additional information on the DPDK vulnerability.
1800
1801Workarounds have been added to ensure vhost compatibility with QEMU 2.12.
1802
1803EXPERIMENTAL: Support for vhost-nvme has been added to the SPDK vhost target. See the
1804[vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
1805
1806### Unified Target Application
1807
1808A new unified SPDK target application, `spdk_tgt`, has been added. This application combines the
1809functionality of several existing SPDK applications, including the iSCSI target, NVMe-oF target,
1810and vhost target. The new application can be managed through the existing configuration file and
1811[JSON-RPC](http://www.spdk.io/doc/jsonrpc.html) methods.
1812
1813### Env
1814
1815spdk_mempool_get_bulk() has been added to wrap DPDK rte_mempool_get_bulk().
1816
1817New memory management functions spdk_malloc(), spdk_zmalloc(), and spdk_free() have been added.
1818These new functions have a `flags` parameter that allows the user to specify whether the allocated
1819memory needs to be suitable for DMA and whether it should be shared across processes with the same
1820shm_id. The new functions are intended to replace spdk_dma_malloc() and related functions, which will
1821eventually be deprecated and removed.
1822
1823### Bdev
1824
1825A new optional bdev module interface function, `init_complete`, has been added to notify bdev modules
1826when the bdev subsystem initialization is complete. This may be useful for virtual bdevs that require
1827notification that the set of initialization examine() calls is complete.
1828
1829The bdev layer now allows modules to provide an optional per-bdev UUID, which can be retrieved with
1830the spdk_bdev_get_uuid() function.
1831
1832Enforcement of IOPS limits for quality of service (QoS) has been added to the bdev layer. See the
1833[set_bdev_qos_limit_iops](http://www.spdk.io/doc/jsonrpc.html#rpc_set_bdev_qos_limit_iops) documentation
1834for more details.
1835
1836### RPC
1837
1838The `[Rpc]` configuration file section, which was deprecated in v18.01, has been removed.
1839Users should switch to the `-r` command-line parameter instead.
1840
1841The JSON-RPC server implementation now allows up to 32 megabyte responses, growing as
1842needed; previously, the response was limited to 32 kilobytes.
1843
1844### SPDKCLI
1845
1846EXPERIMENTAL: New SPDKCLI interactive command tool for managing SPDK is available.
1847See the [SPDKCLI](http://www.spdk.io/doc/spdkcli.html) documentation for more details.
1848
1849### NVMe Driver
1850
1851EXPERIMENTAL: Support for WDS and RDS capable CMBs in NVMe controllers has been added. This support is
1852experimental pending a functional allocator to free and reallocate CMB buffers.
1853
1854spdk_nvme_ns_get_uuid() has been added to allow retrieval of per-namespace UUIDs when available.
1855
1856New API functions spdk_nvme_ctrlr_get_first_active_ns() and spdk_nvme_ctrlr_get_next_active_ns()
1857have been added to iterate active namespaces, as well as spdk_nvme_ctrlr_is_active_ns() to check if
1858a namespace ID is active.
1859
1860### NVMe-oF Target
1861
1862Namespaces may now be assigned unique identifiers via new optional `eui64` and `nguid` parameters
1863to the `nvmf_subsystem_add_ns` RPC method. Additionally, the NVMe-oF target automatically exposes
1864the backing bdev's UUID as the namespace UUID when available.
1865
1866spdk_nvmf_subsystem_remove_ns() is now asynchronous and requires a callback to indicate completion.
1867
1868### Blobstore
1869
1870A number of functions have been renamed:
1871
1872- spdk_bs_io_write_blob() => spdk_blob_io_write()
1873- spdk_bs_io_read_blob() => spdk_blob_io_read()
1874- spdk_bs_io_writev_blob() => spdk_blob_io_writev()
1875- spdk_bs_io_readv_blob() => spdk_blob_io_readv()
1876- spdk_bs_io_unmap_blob() => spdk_blob_io_unmap()
1877- spdk_bs_io_write_zeroes_blob() => spdk_blob_io_write_zeroes()
1878
1879The old names still exist but are deprecated.  They will be removed in the v18.07 release.
1880
1881spdk_blob_resize() is now an asynchronous operation to enable resizing a blob while I/O
1882are in progress to that blob on other threads.  An explicit spdk_blob_sync_md() is still
1883required to sync the updated metadata to disk.
1884
1885### Logical Volumes
1886
1887A new `destroy_lvol_bdev` RPC method to delete logical volumes has been added.
1888
1889Lvols now have their own UUIDs which replace previous LvolStoreUUID_BlobID combination.
1890
1891New Snapshot and Clone functionalities have been added. User may create Snapshots of existing Lvols
1892and Clones of existing Snapshots.
1893See the [lvol snapshots](http://www.spdk.io/doc/logical_volumes.html#lvol_snapshots) documentation
1894for more details.
1895
1896Resizing logical volumes is now supported via the `resize_lvol_bdev` RPC method.
1897
1898### Lib
1899
1900A set of changes were made in the SPDK's lib code altering
1901instances of calls to `exit()` and `abort()` to return a failure instead
1902wherever reasonably possible.
1903
1904spdk_app_start() no longer exit()'s on an internal failure, but
1905instead returns a non-zero error status.
1906
1907spdk_app_parse_args() no longer exit()'s on help, '-h', or an invalid
1908option, but instead returns SPDK_APP_PARSE_ARGS_HELP and
1909SPDK_APP_PARSE_ARGS_FAIL, respectively, and SPDK_APP_PARSE_ARGS_SUCCESS
1910on success.
1911
1912spdk_pci_get_device() has been deprecated and will be removed in SPDK v18.07.
1913
1914### I/O Channels
1915
1916The prototype for spdk_poller_fn() has been modified; it now returns a value indicating
1917whether or not the poller did any work.  Existing pollers will need to be updated to
1918return a value.
1919
1920### iSCSI Target
1921
1922The SPDK iSCSI target now supports the fd.io Vector Packet Processing (VPP) framework userspace
1923TCP/IP stack. See the [iSCSI VPP documentation](http://www.spdk.io/doc/iscsi.html#vpp) for more
1924details.
1925
1926### iSCSI initiator
1927
1928An iSCSI initiator bdev module has been added to SPDK.  This module should be considered
1929experimental pending additional features and tests.  More details can be found in
1930lib/bdev/iscsi/README.
1931
1932### PMDK
1933
1934The persistent memory (PMDK) bdev module is now enabled using `--with-pmdk` instead of
1935`--with-nvml`.  This reflects the renaming of the persistent memory library from NVML to
1936PMDK.
1937
1938### Virtio Block driver
1939
1940A userspace driver for Virtio Block devices has been added. It was built on top of the
1941[Virtio](http://www.spdk.io/doc/virtio.html) library and can be managed similarly to
1942the Virtio SCSI driver. See the
1943[Virtio Block](http://www.spdk.io/doc/bdev.html#bdev_config_virtio_blk) reference for
1944more information.
1945
1946### Virtio with 2MB hugepages
1947
1948The previous 1GB hugepage limitation has now been lifted. A new `-g` command-line option
1949enables SPDK Virtio to work with 2MB hugepages.
1950See [2MB hugepages](http://www.spdk.io/doc/virtio.html#virtio_2mb) for details.
1951
1952## v18.01: Blobstore Thin Provisioning
1953
1954### Build System
1955
1956The build system now includes a `make install` rule, including support for the common
1957`DESTDIR` and `prefix` variables as used in other build systems.  Additionally, the prefix
1958may be set via the configure `--prefix` option.  Example: `make install prefix=/usr`.
1959
1960### RPC
1961
1962A JSON RPC listener is now enabled by default using a UNIX domain socket at /var/run/spdk.sock.
1963A -r option command line option has been added to enable an alternative UNIX domain socket location,
1964or a TCP port in the format ip_addr:tcp_port (i.e. 127.0.0.1:5260).  The Rpc configuration file
1965section is now deprecated and will be removed in the v18.04 release.
1966
1967### I/O Channels
1968
1969spdk_poller_register() and spdk_poller_unregister() were moved from the event
1970framework (include/spdk/event.h) to the I/O channel library
1971(include/spdk/io_channel.h). This allows code that doesn't depend on the event
1972framework to request registration and unregistration of pollers.
1973
1974spdk_for_each_channel() now allows asynchronous operations during iteration.
1975Instead of immediately continuing the interation upon returning from the iteration
1976callback, the user must call spdk_for_each_channel_continue() to resume iteration.
1977
1978### Block Device Abstraction Layer (bdev)
1979
1980The poller abstraction was removed from the bdev layer. There is now a general purpose
1981abstraction for pollers available in include/spdk/io_channel.h
1982
1983### Lib
1984
1985A set of changes were made in the SPDK's lib code altering,
1986instances of calls to `exit()` and `abort()` to return a failure instead
1987wherever reasonably possible.  This has resulted in return type changes of
1988the API for:
1989
1990- spdk_env_init() from type `void` to `int`.
1991- spdk_mem_map_init() from type `void` to `int`.
1992
1993Applications making use of these APIs should be modified to check for
1994a non-zero return value instead of relying on them to fail without return.
1995
1996### NVMe Driver
1997
1998SPDK now supports hotplug for vfio-attached devices. But there is one thing keep in mind:
1999Only physical removal events are supported; removing devices via the sysfs `remove` file will not work.
2000
2001### NVMe-oF Target
2002
2003Subsystems are no longer tied explicitly to CPU cores. Instead, connections are handed out to the available
2004cores round-robin. The "Core" option in the configuration file has been removed.
2005
2006### Blobstore
2007
2008A number of functions have been renamed:
2009
2010- spdk_bs_md_resize_blob() => spdk_blob_resize()
2011- spdk_bs_md_sync_blob() => spdk_blob_sync_md()
2012- spdk_bs_md_close_blob() => spdk_blob_close()
2013- spdk_bs_md_get_xattr_names() => spdk_blob_get_xattr_names()
2014- spdk_bs_md_get_xattr_value() => spdk_blob_get_xattr_value()
2015- spdk_blob_md_set_xattr() => spdk_blob_set_xattr()
2016- spdk_blob_md_remove_xattr() => spdk_blob_remove_xattr()
2017- spdk_bs_md_create_blob() => spdk_bs_create_blob()
2018- spdk_bs_md_open_blob() => spdk_bs_open_blob()
2019- spdk_bs_md_delete_blob() => spdk_bs_delete_blob()
2020- spdk_bs_md_iter_first() => spdk_bs_iter_first()
2021- spdk_bs_md_iter_next() => spdk_bs_iter_next()
2022
2023The function signature of spdk_blob_close() has changed.  It now takes a struct spdk_blob * argument
2024rather than struct spdk_blob **.
2025
2026The function signature of spdk_bs_iter_next() has changed.  It now takes a struct spdk_blob * argument
2027rather than struct spdk_blob **.
2028
2029Thin provisioning support has been added to the blobstore.  It can be enabled by setting the
2030`thin_provision` flag in struct spdk_blob_opts when calling spdk_bs_create_blob_ext().
2031
2032### NBD device
2033
2034The NBD application (test/lib/bdev/nbd) has been removed; Same functionality can now be
2035achieved by using the test/app/bdev_svc application and start_nbd_disk RPC method.
2036See the [GPT](http://www.spdk.io/doc/bdev.html#bdev_config_gpt) documentation for more details.
2037
2038### FIO plugin
2039
2040SPDK `fio_plugin` now supports FIO 3.3. The support for previous FIO 2.21 has been dropped,
2041although it still remains to work for now. The new FIO contains huge amount of bugfixes and
2042it's recommended to do an update.
2043
2044### Virtio library
2045
2046Previously a part of the bdev_virtio module, now a separate library. Virtio is now available
2047via `spdk_internal/virtio.h` file. This is an internal interface to be used when implementing
2048new Virtio backends, namely Virtio-BLK.
2049
2050### iSCSI
2051
2052The MinConnectionIdleInterval parameter has been removed, and connections are no longer migrated
2053to an epoll/kqueue descriptor on the master core when idle.
2054
2055## v17.10: Logical Volumes
2056
2057### New dependencies
2058
2059libuuid was added as new dependency for logical volumes.
2060
2061libnuma is now required unconditionally now that the DPDK submodule has been updated to DPDK 17.08.
2062
2063### Block Device Abstraction Layer (bdev)
2064
2065An [fio](http://github.com/axboe/fio) plugin was added that can route
2066I/O to the bdev layer. See the [plugin documentation](https://github.com/spdk/spdk/tree/master/examples/bdev/fio_plugin/)
2067for more information.
2068
2069spdk_bdev_unmap() was modified to take an offset and a length in bytes as
2070arguments instead of requiring the user to provide an array of SCSI
2071unmap descriptors. This limits unmaps to a single contiguous range.
2072
2073spdk_bdev_write_zeroes() was introduced.  It ensures that all specified blocks will be zeroed out.
2074If a block device doesn't natively support a write zeroes command, the bdev layer emulates it using
2075write commands.
2076
2077New API functions that accept I/O parameters in units of blocks instead of bytes
2078have been added:
2079
2080- spdk_bdev_read_blocks(), spdk_bdev_readv_blocks()
2081- spdk_bdev_write_blocks(), spdk_bdev_writev_blocks()
2082- spdk_bdev_write_zeroes_blocks()
2083- spdk_bdev_unmap_blocks()
2084
2085The bdev layer now handles temporary out-of-memory I/O failures internally by queueing the I/O to be
2086retried later.
2087
2088### Linux AIO bdev
2089
2090The AIO bdev now allows the user to override the auto-detected block size.
2091
2092### NVMe driver
2093
2094The NVMe driver now recognizes the NVMe 1.3 Namespace Optimal I/O Boundary field.
2095NVMe 1.3 devices may report an optimal I/O boundary, which the driver will take
2096into account when splitting I/O requests.
2097
2098The HotplugEnable option in `[Nvme]` sections of the configuration file is now
2099"No" by default. It was previously "Yes".
2100
2101The NVMe library now includes a spdk_nvme_ns_get_ctrlr() function which returns the
2102NVMe Controller associated with a given namespace.
2103
2104The NVMe library now allows the user to specify a host identifier when attaching
2105to a controller.  The host identifier is used as part of the Reservations feature,
2106as well as in the NVMe-oF Connect command.  The default host ID is also now a
2107randomly-generated UUID, and the default host NQN uses the host ID to generate
2108a UUID-based NQN.
2109
2110spdk_nvme_connect() was added to allow the user to connect directly to a single
2111NVMe or NVMe-oF controller.
2112
2113### NVMe-oF Target (nvmf_tgt)
2114
2115The NVMe-oF target no longer requires any in-capsule data buffers to run, and
2116the feature is now entirely optional. Previously, at least 4 KiB in-capsule
2117data buffers were required.
2118
2119NVMe-oF subsytems have a new configuration option, AllowAnyHost, to control
2120whether the host NQN whitelist is enforced when accepting new connections.
2121If no Host options have been specified and AllowAnyHost is disabled, the
2122connection will be denied; this is a behavior change from previous releases,
2123which allowed any host NQN to connect if the Host list was empty.
2124AllowAnyHost is disabled by default.
2125
2126NVMe-oF namespaces may now be assigned arbitrary namespace IDs, and the number
2127of namespaces per subsystem is no longer limited.
2128
2129The NVMe-oF target now supports the Write Zeroes command.
2130
2131### Environment Abstraction Layer
2132
2133A new default value, SPDK_MEMPOOL_DEFAULT_CACHE_SIZE, was added to provide
2134additional clarity when constructing spdk_mempools. Previously, -1 could be
2135passed and the library would choose a reasonable default, but this new value
2136makes it explicit that the default is being used.
2137
2138### Blobstore
2139
2140The blobstore super block now contains a bstype field to identify the type of the blobstore.
2141Existing code should be updated to fill out bstype when calling spdk_bs_init() and spdk_bs_load().
2142
2143spdk_bs_destroy() was added to allow destroying blobstore on device
2144with an initialized blobstore.
2145
2146spdk_bs_io_readv_blob() and spdk_bs_io_writev_blob() were added to enable
2147scattered payloads.
2148
2149A CLI tool for blobstore has been added, allowing basic operations through either command
2150line or shell interface.  See the [blobcli](https://github.com/spdk/spdk/tree/master/examples/blob/cli)
2151documentation for more details.
2152
2153### Event Framework
2154
2155The ability to set a thread name, previously only used by the reactor code, is
2156now part of the spdk_thread_allocate() API.  Users may specify a thread name
2157which will show up in tools like `gdb`.
2158
2159### Log
2160
2161The spdk_trace_dump() function now takes a new parameter to allow the caller to
2162specify an output file handle (stdout or stderr, for example).
2163
2164### Logical Volumes
2165
2166Logical volumes library built on top of SPDK blobstore has been added.
2167It is possible to create logical volumes on top of other devices using RPC.
2168
2169See the [logical volumes](http://www.spdk.io/doc/logical_volumes.html) documentation for more information.
2170
2171### Persistent Memory
2172
2173A new persistent memory bdev type has been added.
2174The persistent memory block device is built on top of [libpmemblk](http://pmem.io/nvml/libpmemblk/).
2175It is possible to create pmem devices on top of pmem pool files using RPC.
2176
2177See the [Pmem Block Device](http://www.spdk.io/doc/bdev.html#bdev_config_pmem) documentation for more information.
2178
2179### Virtio SCSI driver
2180
2181A userspace driver for Virtio SCSI devices has been added.
2182The driver is capable of creating block devices on top of LUNs exposed by another SPDK vhost-scsi application.
2183
2184See the [Virtio SCSI](http://www.spdk.io/doc/virtio.html) documentation and [Getting Started](http://www.spdk.io/doc/bdev.html#bdev_config_virtio_scsi) guide for more information.
2185
2186### Vhost target
2187
2188The vhost target application now supports live migration between QEMU instances.
2189
2190## v17.07: Build system improvements, userspace vhost-blk target, and GPT bdev
2191
2192### Build System
2193
2194A `configure` script has been added to simplify the build configuration process.
2195The existing CONFIG file and `make CONFIG_...` options are also still supported.
2196Run `./configure --help` for information about available configuration options.
2197
2198A DPDK submodule has been added to make building SPDK easier.  If no `--with-dpdk`
2199option is specified to configure, the SPDK build system will automatically build a
2200known-good configuration of DPDK with the minimal options enabled.  See the Building
2201section of README.md for more information.
2202
2203A [Vagrant](https://www.vagrantup.com/) setup has been added to make it easier to
2204develop and use SPDK on systems without suitable NVMe hardware.  See the Vagrant
2205section of README.md for more information.
2206
2207### Userspace vhost-blk target
2208
2209The vhost library and example app have been updated to support the vhost-blk
2210protocol in addition to the existing vhost-scsi protocol.
2211See the [vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
2212
2213### Block device abstraction layer (bdev)
2214
2215A GPT virtual block device has been added, which automatically exposes GPT partitions
2216with a special SPDK-specific partition type as bdevs.
2217See the [GPT bdev documentation](http://www.spdk.io/doc/bdev.md#bdev_config_gpt) for
2218more information.
2219
2220### NVMe driver
2221
2222The NVMe driver has been updated to support recent Intel SSDs, including the Intel®
2223Optane™ SSD DC P4800X series.
2224
2225A workaround has been added for devices that failed to recognize register writes
2226during controller reset.
2227
2228The NVMe driver now allocates request tracking objects on a per-queue basis.  The
2229number of requests allowed on an I/O queue may be set during `spdk_nvme_probe()` by
2230modifying `io_queue_requests` in the opts structure.
2231
2232The SPDK NVMe `fio_plugin` has been updated to support multiple threads (`numjobs`).
2233
2234spdk_nvme_ctrlr_alloc_io_qpair() has been modified to allow the user to override
2235controller-level options for each individual I/O queue pair.
2236Existing callers with qprio == 0 can be updated to:
2237~~~
2238... = spdk_nvme_ctrlr_alloc_io_qpair(ctrlr, NULL, 0);
2239~~~
2240Callers that need to specify a non-default qprio should be updated to:
2241~~~
2242struct spdk_nvme_io_qpair_opts opts;
2243spdk_nvme_ctrlr_get_default_io_qpair_opts(ctrlr, &opts, sizeof(opts));
2244opts.qprio = SPDK_NVME_QPRIO_...;
2245... = spdk_nvme_ctrlr_alloc_io_qpair(ctrlr, &opts, sizeof(opts));
2246~~~
2247
2248### Environment Abstraction Layer
2249
2250The environment abstraction layer has been updated to include several new functions
2251in order to wrap additional DPDK functionality. See `include/spdk/env.h` for the
2252current set of functions.
2253
2254### SPDK Performance Analysis with Intel® VTune™ Amplifier
2255
2256Support for SPDK performance analysis has been added to Intel® VTune™ Amplifier 2018.
2257
2258This analysis provides:
2259
2260- I/O performance monitoring (calculating standard I/O metrics like IOPS, throughput, etc.)
2261- Tuning insights on the interplay of I/O and compute devices by estimating how many cores
2262  would be reasonable to provide for SPDK to keep up with a current storage workload.
2263
2264See the VTune Amplifier documentation for more information.
2265
2266## v17.03: Blobstore and userspace vhost-scsi target
2267
2268### Blobstore and BlobFS
2269
2270The blobstore is a persistent, power-fail safe block allocator designed to be
2271used as the local storage system backing a higher-level storage service.
2272See the [blobstore documentation](http://www.spdk.io/doc/blob.html) for more details.
2273
2274BlobFS adds basic filesystem functionality like filenames on top of the blobstore.
2275This release also includes a RocksDB Env implementation using BlobFS in place of the
2276kernel filesystem.
2277See the [BlobFS documentation](http://www.spdk.io/doc/blobfs.html) for more details.
2278
2279### Userspace vhost-scsi target
2280
2281A userspace implementation of the QEMU vhost-scsi protocol has been added.
2282The vhost target is capable of exporting SPDK bdevs to QEMU-based VMs as virtio devices.
2283See the [vhost documentation](http://www.spdk.io/doc/vhost.html) for more details.
2284
2285### Event framework
2286
2287The overhead of the main reactor event loop was reduced by optimizing the number of
2288calls to spdk_get_ticks() per iteration.
2289
2290### NVMe library
2291
2292The NVMe library will now automatically split readv/writev requests with scatter-gather
2293lists that do not map to valid PRP lists when the NVMe controller does not natively
2294support SGLs.
2295
2296The `identify` and `perf` NVMe examples were modified to add a consistent format for
2297specifying remote NVMe over Fabrics devices via the `-r` option.
2298This is implemented using the new `spdk_nvme_transport_id_parse()` function.
2299
2300### iSCSI Target
2301
2302The [Nvme] section of the configuration file was modified to remove the `BDF` directive
2303and replace it with a `TransportID` directive. Both local (PCIe) and remote (NVMe-oF)
2304devices can now be specified as the backing block device. A script to generate an
2305entire [Nvme] section based on the local NVMe devices attached was added at
2306`scripts/gen_nvme.sh`.
2307
2308### NVMe-oF Target
2309
2310The [Nvme] section of the configuration file was modified to remove the `BDF` directive
2311and replace it with a `TransportID` directive. Both local (PCIe) and remote (NVMe-oF)
2312devices can now be specified as the backing block device. A script to generate an
2313entire [Nvme] section based on the local NVMe devices attached was added at
2314`scripts/gen_nvme.sh`.
2315
2316## v16.12: NVMe over Fabrics host, hotplug, and multi-process
2317
2318### NVMe library
2319
2320The NVMe library has been changed to create its own request memory pool rather than
2321requiring the user to initialize the global `request_mempool` variable.  Apps can be
2322updated by simply removing the initialization of `request_mempool`.  Since the NVMe
2323library user no longer needs to know the size of the internal NVMe request
2324structure to create the pool, the `spdk_nvme_request_size()` function was also removed.
2325
2326The `spdk_nvme_ns_cmd_deallocate()` function was renamed and extended to become
2327`spdk_nvme_ns_cmd_dataset_management()`, which allows access to all of the NVMe
2328Dataset Management command's parameters.  Existing callers can be updated to use
2329`spdk_nvme_ns_cmd_dataset_management()` with `SPDK_NVME_DSM_ATTR_DEALLOCATE` as the
2330`type` parameter.
2331
2332The NVMe library SGL callback prototype has been changed to return virtual addresses
2333rather than physical addresses.  Callers of `spdk_nvme_ns_cmd_readv()` and
2334`spdk_nvme_ns_cmd_writev()` must update their `next_sge_fn` callbacks to match.
2335
2336The NVMe library now supports NVMe over Fabrics devices in addition to the existing
2337support for local PCIe-attached NVMe devices.  For an example of how to enable
2338NVMe over Fabrics support in an application, see `examples/nvme/identify` and
2339`examples/nvme/perf`.
2340
2341Hot insert/remove support for NVMe devices has been added.  To enable NVMe hotplug
2342support, an application should call the `spdk_nvme_probe()` function on a regular
2343basis to probe for new devices (reported via the existing `probe_cb` callback) and
2344removed devices (reported via a new `remove_cb` callback).  Hotplug is currently
2345only supported on Linux with the `uio_pci_generic` driver, and newly-added NVMe
2346devices must be bound to `uio_pci_generic` by an external script or tool.
2347
2348Multiple processes may now coordinate and use a single NVMe device simultaneously
2349using [DPDK Multi-process Support](http://dpdk.org/doc/guides/prog_guide/multi_proc_support.html).
2350
2351### NVMe over Fabrics target (`nvmf_tgt`)
2352
2353The `nvmf_tgt` configuration file format has been updated significantly to enable
2354new features.  See the example configuration file `etc/spdk/nvmf.conf.in` for
2355more details on the new and changed options.
2356
2357The NVMe over Fabrics target now supports virtual mode subsystems, which allow the
2358user to export devices from the SPDK block device abstraction layer as NVMe over
2359Fabrics subsystems.  Direct mode (raw NVMe device access) is also still supported,
2360and a single `nvmf_tgt` may export both types of subsystems simultaneously.
2361
2362### Block device abstraction layer (bdev)
2363
2364The bdev layer now supports scatter/gather read and write I/O APIs, and the NVMe
2365blockdev driver has been updated to support scatter/gather.  Apps can use the
2366new scatter/gather support via the `spdk_bdev_readv()` and `spdk_bdev_writev()`
2367functions.
2368
2369The bdev status returned from each I/O has been extended to pass through NVMe
2370or SCSI status codes directly in cases where the underlying device can provide
2371a more specific status code.
2372
2373A Ceph RBD (RADOS Block Device) blockdev driver has been added.  This allows the
2374`iscsi_tgt` and `nvmf_tgt` apps to export Ceph RBD volumes as iSCSI LUNs or
2375NVMe namespaces.
2376
2377### General changes
2378
2379`libpciaccess` has been removed as a dependency and DPDK PCI enumeration is
2380used instead. Prior to DPDK 16.07 enumeration by class code was not supported,
2381so for earlier DPDK versions, only Intel SSD DC P3x00 devices will be discovered
2382by the NVMe library.
2383
2384The `env` environment abstraction library has been introduced, and a default
2385DPDK-based implementation is provided as part of SPDK.  The goal of the `env`
2386layer is to enable use of alternate user-mode memory allocation and PCI access
2387libraries.  See `doc/porting.md` for more details.
2388
2389The build process has been modified to produce all of the library files in the
2390`build/lib` directory.  This is intended to simplify the use of SPDK from external
2391projects, which can now link to SPDK libraries by adding the `build/lib` directory
2392to the library path via `-L` and linking the SPDK libraries by name (for example,
2393`-lspdk_nvme -lspdk_log -lspdk_util`).
2394
2395`nvmf_tgt` and `iscsi_tgt` now have a JSON-RPC interface, which allows the user
2396to query and modify the configuration at runtime.  The RPC service is disabled by
2397default, since it currently does not provide any authentication or security
2398mechanisms; it should only be enabled on systems with controlled user access
2399behind a firewall. An example RPC client implemented in Python is provided in
2400`scripts/rpc.py`.
2401
2402## v16.08: iSCSI target, NVMe over Fabrics maturity
2403
2404This release adds a userspace iSCSI target. The iSCSI target is capable of exporting
2405NVMe devices over a network using the iSCSI protocol. The application is located
2406in app/iscsi_tgt and a documented configuration file can be found at etc/spdk/spdk.conf.in.
2407
2408This release also significantly improves the existing NVMe over Fabrics target.
2409
2410  - The configuration file format was changed, which will require updates to
2411    any existing nvmf.conf files (see `etc/spdk/nvmf.conf.in`):
2412    - `SubsystemGroup` was renamed to `Subsystem`.
2413    - `AuthFile` was removed (it was unimplemented).
2414    - `nvmf_tgt` was updated to correctly recognize NQN (NVMe Qualified Names)
2415      when naming subsystems.  The default node name was changed to reflect this;
2416      it is now "nqn.2016-06.io.spdk".
2417    - `Port` and `Host` sections were merged into the `Subsystem` section
2418    - Global options to control max queue depth, number of queues, max I/O
2419      size, and max in-capsule data size were added.
2420    - The Nvme section was removed. Now a list of devices is specified by
2421      bus/device/function directly in the Subsystem section.
2422    - Subsystems now have a Mode, which can be Direct or Virtual. This is an attempt
2423      to future-proof the interface, so the only mode supported by this release
2424      is "Direct".
2425  - Many bug fixes and cleanups were applied to the `nvmf_tgt` app and library.
2426  - The target now supports discovery.
2427
2428This release also adds one new feature and provides some better examples and tools
2429for the NVMe driver.
2430
2431  - The Weighted Round Robin arbitration method is now supported. This allows
2432    the user to specify different priorities on a per-I/O-queue basis.  To
2433    enable WRR, set the `arb_mechanism` field during `spdk_nvme_probe()`.
2434  - A simplified "Hello World" example was added to show the proper way to use
2435    the NVMe library API; see `examples/nvme/hello_world/hello_world.c`.
2436  - A test for measuring software overhead was added. See `test/lib/nvme/overhead`.
2437
2438## v16.06: NVMf userspace target
2439
2440This release adds a userspace NVMf (NVMe over Fabrics) target, conforming to the
2441newly-released NVMf 1.0/NVMe 1.2.1 specification.  The NVMf target exports NVMe
2442devices from a host machine over the network via RDMA.  Currently, the target is
2443limited to directly exporting physical NVMe devices, and the discovery subsystem
2444is not supported.
2445
2446This release includes a general API cleanup, including renaming all declarations
2447in public headers to include a `spdk` prefix to prevent namespace clashes with
2448user code.
2449
2450- NVMe
2451  - The `nvme_attach()` API was reworked into a new probe/attach model, which
2452  moves device detection into the NVMe library.  The new API also allows
2453  parallel initialization of NVMe controllers, providing a major reduction in
2454  startup time when using multiple controllers.
2455  - I/O queue allocation was changed to be explicit in the API.  Each function
2456  that generates I/O requests now takes a queue pair (`spdk_nvme_qpair *`)
2457  argument, and I/O queues may be allocated using
2458  `spdk_nvme_ctrlr_alloc_io_qpair()`.  This allows more flexible assignment of
2459  queue pairs than the previous model, which only allowed a single queue
2460  per thread and limited the total number of I/O queues to the lowest number
2461  supported on any attached controller.
2462  - Added support for the Write Zeroes command.
2463  - `examples/nvme/perf` can now report I/O command latency from the
2464   the controller's viewpoint using the Intel vendor-specific read/write latency
2465   log page.
2466  - Added namespace reservation command support, which can be used to coordinate
2467  sharing of a namespace between multiple hosts.
2468  - Added hardware SGL support, which enables use of scattered buffers that
2469   don't conform to the PRP list alignment and length requirements on supported
2470   NVMe controllers.
2471  - Added end-to-end data protection support, including the ability to write and
2472  read metadata in extended LBA (metadata appended to each block of data in the
2473  buffer) and separate metadata buffer modes.
2474  See `spdk_nvme_ns_cmd_write_with_md()` and `spdk_nvme_ns_cmd_read_with_md()`
2475  for details.
2476- IOAT
2477  - The DMA block fill feature is now exposed via the `ioat_submit_fill()`
2478  function.  This is functionally similar to `memset()`, except the memory is
2479  filled with an 8-byte repeating pattern instead of a single byte like memset.
2480- PCI
2481  - Added support for using DPDK for PCI device mapping in addition to the
2482  existing libpciaccess option.  Using the DPDK PCI support also allows use of
2483  the Linux VFIO driver model, which means that SPDK userspace drivers will work
2484  with the IOMMU enabled.  Additionally, SPDK applications may be run as an
2485  unprivileged user with access restricted to a specific set of PCIe devices.
2486  - The PCI library API was made more generic to abstract away differences
2487  between the underlying PCI access implementations.
2488
2489## v1.2.0: IOAT user-space driver
2490
2491This release adds a user-space driver with support for the Intel I/O Acceleration Technology (I/OAT, also known as "Crystal Beach") DMA offload engine.
2492
2493- IOAT
2494  - New user-space driver supporting DMA memory copy offload
2495  - Example programs `ioat/perf` and `ioat/verify`
2496  - Kernel-mode DMA engine test driver `kperf` for performance comparison
2497- NVMe
2498  - Per-I/O flags for Force Unit Access (FUA) and Limited Retry
2499  - Public API for retrieving log pages
2500  - Reservation register/acquire/release/report command support
2501  - Scattered payload support - an alternate API to provide I/O buffers via a sequence of callbacks
2502  - Declarations and `nvme/identify` support for Intel SSD DC P3700 series vendor-specific log pages and features
2503- Updated to support DPDK 2.2.0
2504
2505## v1.0.0: NVMe user-space driver
2506
2507This is the initial open source release of the Storage Performance Development Kit (SPDK).
2508
2509Features:
2510
2511- NVMe user-space driver
2512- NVMe example programs
2513  - `examples/nvme/perf` tests performance (IOPS) using the NVMe user-space driver
2514  - `examples/nvme/identify` displays NVMe controller information in a human-readable format
2515- Linux and FreeBSD support
2516