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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2022-07-26 05:25:24 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2022-07-26 05:25:24 +0000 |
commit | acf73199fa227b97217238334236af367c8ab2d7 (patch) | |
tree | b6812bd6cbe6b977884ec94def20de59555983d5 /doc/rst/mi.rst | |
parent | Adding upstream version 1.0. (diff) | |
download | libnvme-acf73199fa227b97217238334236af367c8ab2d7.tar.xz libnvme-acf73199fa227b97217238334236af367c8ab2d7.zip |
Adding upstream version 1.1~rc0.upstream/1.1_rc0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | doc/rst/mi.rst | 1590 |
1 files changed, 1590 insertions, 0 deletions
diff --git a/doc/rst/mi.rst b/doc/rst/mi.rst new file mode 100644 index 0000000..b9f2f84 --- /dev/null +++ b/doc/rst/mi.rst @@ -0,0 +1,1590 @@ +.. _mi.h - NVMe Management Interface library (libnvme-mi) definitions.: + +**mi.h - NVMe Management Interface library (libnvme-mi) definitions.** + + +These provide an abstraction for the MI messaging between controllers +and a host, typically over an MCTP-over-i2c link to a NVMe device, used +as part of the out-of-band management of a system. + +We have a few data structures define here to reflect the topology +of a MI connection with an NVMe subsystem: + + - :c:type:`nvme_mi_ep_t`: an MI endpoint - our mechanism of communication with a + NVMe subsystem. For MCTP, an endpoint will be the component that + holds the MCTP address (EID), and receives our request message. + + endpoints are defined in the NVMe-MI spec, and are specific to the MI + interface. + + Each endpoint will provide access to one or more of: + + - :c:type:`nvme_mi_ctrl_t`: a NVMe controller, as defined by the NVMe base spec. + The controllers are responsible for processing any NVMe standard + commands (eg, the Admin command set). An endpoint (:c:type:`nvme_mi_ep_t`) + may provide access to multiple controllers - so each of the controller- + type commands will require a :c:type:`nvme_mi_ctrl_t` to be specified, rather than + an endpoint + +A couple of conventions with the libnvme-mi API: + + - All types and functions have the nvme_mi prefix, to distinguish from + the libnvme core. + + - We currently support either MI commands and Admin commands. The + former adds a _mi prefix, the latter an _admin prefix. [This does + result in the MI functions having a double _mi, like + :c:type:`nvme_mi_mi_subsystem_health_status_poll`, which is apparently amusing + for our German-speaking readers] + +For return values: unless specified in the per-function documentation, +all functions: + + - return 0 on success + + - return -1, with errno set, for errors communicating with the MI device, + either in request or response data + + - return >1 on MI status errors. This value is the 8-bit MI status + value, represented by :c:type:`enum nvme_mi_resp_status <nvme_mi_resp_status>`. Note that the + status values may be vendor-defined above 0xe0. + +For the second case, we have a few conventions for errno values: + + - EPROTO: response data violated the MI protocol, and libnvme cannot + validly interpret the response + + - EIO: Other I/O error communicating with device (eg., valid but + unexpected response data) + + - EINVAL: invalid input arguments for a command + +In line with the core NVMe API, the Admin command functions take an +`_args` structure to provide the command-specific parameters. However, +for the MI interface, the fd and timeout members of these _args structs +are ignored. + +References to the specifications here will either to be the NVM Express +Management Interface ("NVMe-MI") or the NVM Express Base specification +("NVMe"). At the time of writing, the versions we're referencing here +are: + - NVMe-MI 1.2b + - NVMe 2.0b +with a couple of accommodations for older spec types, particularly NVMe-MI +1.1, where possible. + +.. c:macro:: NVME_MI_MSGTYPE_NVME + +``NVME_MI_MSGTYPE_NVME ()`` + + MCTP message type for NVMe-MI messages. + +**Parameters** + +**Description** + + +This is defined by MCTP, but is referenced as part of the NVMe-MI message +spec. This is the MCTP NVMe message type (0x4), with the message-integrity +bit (0x80) set. + + + + +.. c:enum:: nvme_mi_message_type + + NVMe-MI message type field. + +**Constants** + +``NVME_MI_MT_CONTROL`` + NVME-MI Control Primitive + +``NVME_MI_MT_MI`` + NVMe-MI command + +``NVME_MI_MT_ADMIN`` + NVMe Admin command + +``NVME_MI_MT_PCIE`` + PCIe command + +**Description** + +Used as byte 1 of both request and response messages (NMIMT bits of NMP +byte). Not to be confused with the MCTP message type in byte 0. + + + + +.. c:enum:: nvme_mi_ror + + Request or response field. + +**Constants** + +``NVME_MI_ROR_REQ`` + request message + +``NVME_MI_ROR_RSP`` + response message + + + + +.. c:enum:: nvme_mi_resp_status + + values for the response status field + +**Constants** + +``NVME_MI_RESP_SUCCESS`` + success + +``NVME_MI_RESP_MPR`` + More Processing Required + +``NVME_MI_RESP_INTERNAL_ERR`` + Internal Error + +``NVME_MI_RESP_INVALID_OPCODE`` + Invalid command opcode + +``NVME_MI_RESP_INVALID_PARAM`` + Invalid command parameter + +``NVME_MI_RESP_INVALID_CMD_SIZE`` + Invalid command size + +``NVME_MI_RESP_INVALID_INPUT_SIZE`` + Invalid command input data size + +``NVME_MI_RESP_ACCESS_DENIED`` + Access Denied + +``NVME_MI_RESP_VPD_UPDATES_EXCEEDED`` + More VPD updates than allowed + +``NVME_MI_RESP_PCIE_INACCESSIBLE`` + PCIe functionality currently unavailable + +``NVME_MI_RESP_MEB_SANITIZED`` + MEB has been cleared due to sanitize + +``NVME_MI_RESP_ENC_SERV_FAILURE`` + Enclosure services process failed + +``NVME_MI_RESP_ENC_SERV_XFER_FAILURE`` + Transfer with enclosure services failed + +``NVME_MI_RESP_ENC_FAILURE`` + Unreoverable enclosure failure + +``NVME_MI_RESP_ENC_XFER_REFUSED`` + Enclosure services transfer refused + +``NVME_MI_RESP_ENC_FUNC_UNSUP`` + Unsupported enclosure services function + +``NVME_MI_RESP_ENC_SERV_UNAVAIL`` + Enclosure services unavailable + +``NVME_MI_RESP_ENC_DEGRADED`` + Noncritical failure detected by enc. services + +``NVME_MI_RESP_SANITIZE_IN_PROGRESS`` + Command prohibited during sanitize + + + + +.. c:struct:: nvme_mi_msg_hdr + + General MI message header. + +**Definition** + +:: + + struct nvme_mi_msg_hdr { + __u8 type; + __u8 nmp; + __u8 meb; + __u8 rsvd0; + }; + +**Members** + +``type`` + MCTP message type, will always be NVME_MI_MSGTYPE_NVME + +``nmp`` + NVMe-MI message parameters (including MI message type) + +``meb`` + Management Endpoint Buffer flag; unused for libnvme-mi implementation + +``rsvd0`` + currently reserved + + +**Description** + +Wire format shared by both request and response messages, per NVMe-MI +section 3.1. This is used for all message types, MI and Admin. + + + + +.. c:struct:: nvme_mi_msg_resp + + Generic response type. + +**Definition** + +:: + + struct nvme_mi_msg_resp { + struct nvme_mi_msg_hdr hdr; + __u8 status; + __u8 rsvd0[3]; + }; + +**Members** + +``hdr`` + the general request/response message header + +``status`` + response status value (see :c:type:`enum nvme_mi_resp_status <nvme_mi_resp_status>`) + +``rsvd0`` + reserved data, may be defined by specific response + + +**Description** + +Every response will start with one of these; command-specific responses +will define parts of the reserved data, and may add further fields. + + + + +.. c:enum:: nvme_mi_mi_opcode + + Operation code for supported NVMe-MI commands. + +**Constants** + +``nvme_mi_mi_opcode_mi_data_read`` + Read NVMe-MI Data Structure + +``nvme_mi_mi_opcode_subsys_health_status_poll`` + Subsystem Health Status Poll + +``nvme_mi_mi_opcode_configuration_set`` + MI Configuration Set + +``nvme_mi_mi_opcode_configuration_get`` + MI Configuration Get + + + + +.. c:struct:: nvme_mi_mi_req_hdr + + MI request message header. + +**Definition** + +:: + + struct nvme_mi_mi_req_hdr { + struct nvme_mi_msg_hdr hdr; + __u8 opcode; + __u8 rsvd0[3]; + __le32 cdw0, cdw1; + }; + +**Members** + +``hdr`` + generic MI message header + +``opcode`` + opcode (OPC) for the specific MI command + +``rsvd0`` + reserved bytes + +``cdw0`` + Management Request Doubleword 0 - command specific usage + +``cdw1`` + Management Request Doubleword 1 - command specific usage + + +**Description** + +Wire format for MI request message headers, defined in section 5 of NVMe-MI. + + + + +.. c:struct:: nvme_mi_mi_resp_hdr + + MI response message header. + +**Definition** + +:: + + struct nvme_mi_mi_resp_hdr { + struct nvme_mi_msg_hdr hdr; + __u8 status; + __u8 nmresp[3]; + }; + +**Members** + +``hdr`` + generic MI message header + +``status`` + generic response status from command; non-zero on failure. + +``nmresp`` + NVMe Management Response: command-type-specific response data + + +**Description** + +Wire format for MI response message header, defined in section 5 of NVMe-MI. + + + + +.. c:enum:: nvme_mi_dtyp + + Data Structure Type field. + +**Constants** + +``nvme_mi_dtyp_subsys_info`` + NVM Subsystem Information + +``nvme_mi_dtyp_port_info`` + Port information + +``nvme_mi_dtyp_ctrl_list`` + Controller List + +``nvme_mi_dtyp_ctrl_info`` + Controller Information + +``nvme_mi_dtyp_opt_cmd_support`` + Optionally Supported Command List + +``nvme_mi_dtyp_meb_support`` + Management Endpoint Buffer Command Support List + +**Description** + +Data Structure Type field for Read NVMe-MI Data Structure command, used to +indicate the particular structure to query from the endpoint. + + + + +.. c:enum:: nvme_mi_config_id + + NVMe-MI Configuration identifier. + +**Constants** + +``NVME_MI_CONFIG_SMBUS_FREQ`` + Current SMBus/I2C frequency + +``NVME_MI_CONFIG_HEALTH_STATUS_CHANGE`` + Health Status change - used to clear + health status bits in CCS bits of + status poll. Only for Set ops. + +``NVME_MI_CONFIG_MCTP_MTU`` + MCTP maximum transmission unit size of port + specified in dw 0 + +**Description** + +Configuration parameters for the MI Get/Set Configuration commands. + +See :c:type:`nvme_mi_mi_config_get`() and :c:type:`nvme_mi_config_set`(). + + + + +.. c:enum:: nvme_mi_config_smbus_freq + + SMBus/I2C frequency values + +**Constants** + +``NVME_MI_CONFIG_SMBUS_FREQ_100kHz`` + 100kHz + +``NVME_MI_CONFIG_SMBUS_FREQ_400kHz`` + 400kHz + +``NVME_MI_CONFIG_SMBUS_FREQ_1MHz`` + 1MHz + +**Description** + +Values used in the SMBus Frequency device configuration. See +:c:type:`nvme_mi_mi_config_get_smbus_freq`() and :c:type:`nvme_mi_mi_config_set_smbus_freq`(). + + + + +.. c:struct:: nvme_mi_admin_req_hdr + + Admin command request header. + +**Definition** + +:: + + struct nvme_mi_admin_req_hdr { + struct nvme_mi_msg_hdr hdr; + __u8 opcode; + __u8 flags; + __le16 ctrl_id; + __le32 cdw1, cdw2, cdw3, cdw4, cdw5; + __le32 doff; + __le32 dlen; + __le32 rsvd0, rsvd1; + __le32 cdw10, cdw11, cdw12, cdw13, cdw14, cdw15; + }; + +**Members** + +``hdr`` + Generic MI message header + +``opcode`` + Admin command opcode (using enum nvme_admin_opcode) + +``flags`` + Command Flags, indicating dlen and doff validity; Only defined in + NVMe-MI version 1.1, no fields defined in 1.2 (where the dlen/doff + are always considered valid). + +``ctrl_id`` + Controller ID target of command + +``cdw1`` + Submission Queue Entry doubleword 1 + +``cdw2`` + Submission Queue Entry doubleword 2 + +``cdw3`` + Submission Queue Entry doubleword 3 + +``cdw4`` + Submission Queue Entry doubleword 4 + +``cdw5`` + Submission Queue Entry doubleword 5 + +``doff`` + Offset of data to return from command + +``dlen`` + Length of sent/returned data + +``rsvd0`` + Reserved + +``rsvd1`` + Reserved + +``cdw10`` + Submission Queue Entry doubleword 10 + +``cdw11`` + Submission Queue Entry doubleword 11 + +``cdw12`` + Submission Queue Entry doubleword 12 + +``cdw13`` + Submission Queue Entry doubleword 13 + +``cdw14`` + Submission Queue Entry doubleword 14 + +``cdw15`` + Submission Queue Entry doubleword 15 + + +**Description** + +Wire format for Admin command message headers, defined in section 6 of +NVMe-MI. + + + + +.. c:struct:: nvme_mi_admin_resp_hdr + + Admin command response header. + +**Definition** + +:: + + struct nvme_mi_admin_resp_hdr { + struct nvme_mi_msg_hdr hdr; + __u8 status; + __u8 rsvd0[3]; + __le32 cdw0, cdw1, cdw3; + }; + +**Members** + +``hdr`` + Generic MI message header + +``status`` + Generic response code, non-zero on failure + +``rsvd0`` + Reserved + +``cdw0`` + Completion Queue Entry doubleword 0 + +``cdw1`` + Completion Queue Entry doubleword 1 + +``cdw3`` + Completion Queue Entry doubleword 3 + + +**Description** + +This is the generic response format with the three doublewords of completion +queue data, plus optional response data. + + +.. c:function:: nvme_root_t nvme_mi_create_root (FILE *fp, int log_level) + + Create top-level MI (root) handle. + +**Parameters** + +``FILE *fp`` + File descriptor for logging messages + +``int log_level`` + Logging level to use + +**Description** + +Create the top-level (library) handle for creating subsequent endpoint +objects. Similar to nvme_create_root(), but we provide this to allow linking +without the core libnvme. + +See :c:type:`nvme_create_root`. + +**Return** + +new root object, or NULL on failure. + + +.. c:function:: void nvme_mi_free_root (nvme_root_t root) + + Free root object. + +**Parameters** + +``nvme_root_t root`` + root to free + + + + +.. c:type:: nvme_mi_ep_t + + MI Endpoint object. + +**Description** + + +Represents our communication endpoint on the remote MI-capable device. +To be used for direct MI commands for the endpoint (through the +nvme_mi_mi_* functions(), or to communicate with individual controllers +(see :c:type:`nvme_mi_init_ctrl`). + +Endpoints are created through a transport-specific constructor; currently +only MCTP-connected endpoints are supported, through :c:type:`nvme_mi_open_mctp`. +Subsequent operations on the endpoint (and related controllers) are +transport-independent. + + +.. c:function:: nvme_mi_ep_t nvme_mi_first_endpoint (nvme_root_t m) + + Start endpoint iterator + +**Parameters** + +``nvme_root_t m`` + :c:type:`nvme_root_t` object + +**Return** + +first MI endpoint object under this root, or NULL if no endpoints + are present. + +**Description** + +See: :c:type:`nvme_mi_next_endpoint`, :c:type:`nvme_mi_for_each_endpoint` + + +.. c:function:: nvme_mi_ep_t nvme_mi_next_endpoint (nvme_root_t m, nvme_mi_ep_t e) + + Continue endpoint iterator + +**Parameters** + +``nvme_root_t m`` + :c:type:`nvme_root_t` object + +``nvme_mi_ep_t e`` + :c:type:`nvme_mi_ep_t` current position of iterator + +**Return** + +next endpoint MI endpoint object after **e** under this root, or NULL + if no further endpoints are present. + +**Description** + +See: :c:type:`nvme_mi_first_endpoint`, :c:type:`nvme_mi_for_each_endpoint` + + +.. c:macro:: nvme_mi_for_each_endpoint + +``nvme_mi_for_each_endpoint (m, e)`` + + Iterator for NVMe-MI endpoints. + +**Parameters** + +``m`` + :c:type:`nvme_root_t` containing endpoints + +``e`` + :c:type:`nvme_mi_ep_t` object, set on each iteration + + +.. c:macro:: nvme_mi_for_each_endpoint_safe + +``nvme_mi_for_each_endpoint_safe (m, e, _e)`` + + Iterator for NVMe-MI endpoints, allowing deletion during traversal + +**Parameters** + +``m`` + :c:type:`nvme_root_t` containing endpoints + +``e`` + :c:type:`nvme_mi_ep_t` object, set on each iteration + +``_e`` + :c:type:`nvme_mi_ep_t` object used as temporary storage + + + + +.. c:type:: nvme_mi_ctrl_t + + NVMe-MI Controller object. + +**Description** + + +Provides NVMe command functionality, through the MI interface. + + +.. c:function:: nvme_mi_ctrl_t nvme_mi_first_ctrl (nvme_mi_ep_t ep) + + Start controller iterator + +**Parameters** + +``nvme_mi_ep_t ep`` + :c:type:`nvme_mi_ep_t` object + +**Return** + +first MI controller object under this root, or NULL if no controllers + are present. + +**Description** + +See: :c:type:`nvme_mi_next_ctrl`, :c:type:`nvme_mi_for_each_ctrl` + + +.. c:function:: nvme_mi_ctrl_t nvme_mi_next_ctrl (nvme_mi_ep_t ep, nvme_mi_ctrl_t c) + + Continue ctrl iterator + +**Parameters** + +``nvme_mi_ep_t ep`` + :c:type:`nvme_mi_ep_t` object + +``nvme_mi_ctrl_t c`` + :c:type:`nvme_mi_ctrl_t` current position of iterator + +**Return** + +next MI controller object after **c** under this endpoint, or NULL + if no further controllers are present. + +**Description** + +See: :c:type:`nvme_mi_first_ctrl`, :c:type:`nvme_mi_for_each_ctrl` + + +.. c:macro:: nvme_mi_for_each_ctrl + +``nvme_mi_for_each_ctrl (ep, c)`` + + Iterator for NVMe-MI controllers. + +**Parameters** + +``ep`` + :c:type:`nvme_mi_ep_t` containing endpoints + +``c`` + :c:type:`nvme_mi_ctrl_t` object, set on each iteration + +**Description** + +Allows iteration of the list of controllers behind an endpoint. Unless the +controllers have already been created explicitly, you'll probably want to +call :c:type:`nvme_mi_scan_ep`() to scan for the controllers first. + +See: :c:type:`nvme_mi_scan_ep`() + + +.. c:macro:: nvme_mi_for_each_ctrl_safe + +``nvme_mi_for_each_ctrl_safe (ep, c, _c)`` + + Iterator for NVMe-MI controllers, allowing deletion during traversal + +**Parameters** + +``ep`` + :c:type:`nvme_mi_ep_t` containing controllers + +``c`` + :c:type:`nvme_mi_ctrl_t` object, set on each iteration + +``_c`` + :c:type:`nvme_mi_ctrl_t` object used as temporary storage + +**Description** + +Allows iteration of the list of controllers behind an endpoint, safe against +deletion during iteration. Unless the controllers have already been created +explicitly (or you're just iterating to destroy controllers) you'll probably +want to call :c:type:`nvme_mi_scan_ep`() to scan for the controllers first. + +See: :c:type:`nvme_mi_scan_ep`() + + +.. c:function:: nvme_mi_ep_t nvme_mi_open_mctp (nvme_root_t root, unsigned int netid, uint8_t eid) + + Create an endpoint using a MCTP connection. + +**Parameters** + +``nvme_root_t root`` + root object to create under + +``unsigned int netid`` + MCTP network ID on this system + +``uint8_t eid`` + MCTP endpoint ID + +**Description** + +Transport-specific endpoint initialization for MI-connected endpoints. Once +an endpoint is created, the rest of the API is transport-independent. + +See :c:type:`nvme_mi_close` + +**Return** + +New endpoint object for **netid** & **eid**, or NULL on failure. + + +.. c:function:: void nvme_mi_close (nvme_mi_ep_t ep) + + Close an endpoint connection and release resources, including controller objects. + +**Parameters** + +``nvme_mi_ep_t ep`` + Endpoint object to close + + +.. c:function:: nvme_root_t nvme_mi_scan_mctp (void) + + look for MCTP-connected NVMe-MI endpoints. + +**Parameters** + +``void`` + no arguments + +**Description** + +This function queries the system MCTP daemon ("mctpd") over +D-Bus, to find MCTP endpoints that report support for NVMe-MI over MCTP. + +This requires libvnme-mi to be compiled with D-Bus support; if not, this +will return NULL. + +**Return** + +A **nvme_root_t** populated with a set of MCTP-connected endpoints, + or NULL on failure + + +.. c:function:: int nvme_mi_scan_ep (nvme_mi_ep_t ep, bool force_rescan) + + query an endpoint for its NVMe controllers. + +**Parameters** + +``nvme_mi_ep_t ep`` + Endpoint to scan + +``bool force_rescan`` + close existing controllers and rescan + +**Description** + +This function queries an MI endpoint for the controllers available, by +performing an MI Read MI Data Structure command (requesting the +controller list). The controllers are stored in the endpoint's internal +list, and can be iterated with nvme_mi_for_each_ctrl. + +This will only scan the endpoint once, unless **force_rescan** is set. If +so, all existing controller objects will be freed - the caller must not +hold a reference to those across this call. + +See: :c:type:`nvme_mi_for_each_ctrl` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: nvme_mi_ctrl_t nvme_mi_init_ctrl (nvme_mi_ep_t ep, __u16 ctrl_id) + + initialise a NVMe controller. + +**Parameters** + +``nvme_mi_ep_t ep`` + Endpoint to create under + +``__u16 ctrl_id`` + ID of controller to initialize. + +**Description** + +Create a connection to a controller behind the endpoint specified in **ep**. +Controller IDs may be queried from the endpoint through +:c:type:`nvme_mi_mi_read_mi_data_ctrl_list`. + +See :c:type:`nvme_mi_close_ctrl` + +**Return** + +New controller object, or NULL on failure. + + +.. c:function:: void nvme_mi_close_ctrl (nvme_mi_ctrl_t ctrl) + + free a controller + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + controller to free + + +.. c:function:: char * nvme_mi_endpoint_desc (nvme_mi_ep_t ep) + + Get a string describing a MI endpoint. + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint to describe + +**Description** + +Generates a human-readable string describing the endpoint, with possibly +transport-specific data. The string is allocated during the call, and the +caller is responsible for free()-ing the string. + +**Return** + +a newly-allocated string containing the endpoint description, or + NULL on failure. + + +.. c:function:: int nvme_mi_mi_read_mi_data_subsys (nvme_mi_ep_t ep, struct nvme_mi_read_nvm_ss_info *s) + + Perform a Read MI Data Structure command, retrieving subsystem data. + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``struct nvme_mi_read_nvm_ss_info *s`` + subsystem information to populate + +**Description** + +Retrieves the Subsystem information - number of external ports and +NVMe version information. See :c:type:`struct nvme_mi_read_nvm_ss_info <nvme_mi_read_nvm_ss_info>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_read_mi_data_port (nvme_mi_ep_t ep, __u8 portid, struct nvme_mi_read_port_info *p) + + Perform a Read MI Data Structure command, retrieving port data. + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 portid`` + id of port data to retrieve + +``struct nvme_mi_read_port_info *p`` + port information to populate + +**Description** + +Retrieves the Port information, for the specified port ID. The subsystem +data (from :c:type:`nvme_mi_mi_read_mi_data_subsys`) nmp field contains the allowed +range of port IDs. + +See :c:type:`struct nvme_mi_read_port_info <nvme_mi_read_port_info>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_read_mi_data_ctrl_list (nvme_mi_ep_t ep, __u8 start_ctrlid, struct nvme_ctrl_list *list) + + Perform a Read MI Data Structure command, retrieving the list of attached controllers. + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 start_ctrlid`` + starting controller ID + +``struct nvme_ctrl_list *list`` + controller list to populate + +**Description** + +Retrieves the list of attached controllers, with IDs greater than or +equal to **start_ctrlid**. + +See :c:type:`struct nvme_ctrl_list <nvme_ctrl_list>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_read_mi_data_ctrl (nvme_mi_ep_t ep, __u16 ctrl_id, struct nvme_mi_read_ctrl_info *ctrl) + + Perform a Read MI Data Structure command, retrieving controller information + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u16 ctrl_id`` + ID of controller to query + +``struct nvme_mi_read_ctrl_info *ctrl`` + controller data to populate + +**Description** + +Retrieves the Controller Information Data Structure for the attached +controller with ID **ctrlid**. + +See :c:type:`struct nvme_mi_read_ctrl_info <nvme_mi_read_ctrl_info>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_subsystem_health_status_poll (nvme_mi_ep_t ep, bool clear, struct nvme_mi_nvm_ss_health_status *nshds) + + Read the Subsystem Health Data Structure from the NVM subsystem + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``bool clear`` + flag to clear the Composite Controller Status state + +``struct nvme_mi_nvm_ss_health_status *nshds`` + subsystem health status data to populate + +**Description** + +Retrieves the Subsystem Health Data Structure into **nshds**. If **clear** is +set, requests that the Composite Controller Status bits are cleared after +the read. See NVMe-MI section 5.6 for details on the CCS bits. + +See :c:type:`struct nvme_mi_nvm_ss_health_status <nvme_mi_nvm_ss_health_status>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_get (nvme_mi_ep_t ep, __u32 dw0, __u32 dw1, __u32 *nmresp) + + query a configuration parameter + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u32 dw0`` + management doubleword 0, containing configuration identifier, plus + config-specific fields + +``__u32 dw1`` + management doubleword 0, config-specific. + +``__u32 *nmresp`` + set to queried configuration data in NMRESP field of response. + +**Description** + +Performs a MI Configuration Get command, with the configuration identifier +as the LSB of **dw0**. Other **dw0** and **dw1** data is configuration-identifier +specific. + +On a successful Configuration Get, the **nmresp** pointer will be populated with +the bytes from the 3-byte NMRESP field, converted to native endian. + +See :c:type:`enum nvme_mi_config_id <nvme_mi_config_id>` for identifiers. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_set (nvme_mi_ep_t ep, __u32 dw0, __u32 dw1) + + set a configuration parameter + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u32 dw0`` + management doubleword 0, containing configuration identifier, plus + config-specific fields + +``__u32 dw1`` + management doubleword 0, config-specific. + +**Description** + +Performs a MI Configuration Set command, with the command as the LSB of +**dw0**. Other **dw0** and **dw1** data is configuration-identifier specific. + +See :c:type:`enum nvme_mi_config_id <nvme_mi_config_id>` for identifiers. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_get_smbus_freq (nvme_mi_ep_t ep, __u8 port, enum nvme_mi_config_smbus_freq *freq) + + get configuration: SMBus port frequency + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 port`` + port ID to query + +``enum nvme_mi_config_smbus_freq *freq`` + output value for current frequency configuration + +**Description** + +Performs a MI Configuration Get, to query the current SMBus frequency of +the port specified in **port**. On success, populates **freq** with the port +frequency + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_set_smbus_freq (nvme_mi_ep_t ep, __u8 port, enum nvme_mi_config_smbus_freq freq) + + set configuration: SMBus port frequency + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 port`` + port ID to set + +``enum nvme_mi_config_smbus_freq freq`` + new frequency configuration + +**Description** + +Performs a MI Configuration Set, to update the current SMBus frequency of +the port specified in **port**. + +See :c:type:`struct nvme_mi_read_port_info <nvme_mi_read_port_info>` for the maximum supported SMBus frequency +for the port. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_set_health_status_change (nvme_mi_ep_t ep, __u32 mask) + + clear CCS bits in health status + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u32 mask`` + bitmask to clear + +**Description** + +Performs a MI Configuration Set, to update the current health status poll +values of the Composite Controller Status bits. Bits set in **mask** will +be cleared from future health status poll data, and may be re-triggered by +a future health change event. + +See :c:type:`nvme_mi_mi_subsystem_health_status_poll`(), :c:type:`enum nvme_mi_ccs <nvme_mi_ccs>` for +values in **mask**. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_get_mctp_mtu (nvme_mi_ep_t ep, __u8 port, __u16 *mtu) + + get configuration: MCTP MTU + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 port`` + port ID to query + +``__u16 *mtu`` + output value for current MCTP MTU configuration + +**Description** + +Performs a MI Configuration Get, to query the current MCTP Maximum +Transmission Unit size (MTU) of the port specified in **port**. On success, +populates **mtu** with the MTU. + +The default reset value is 64, corresponding to the MCTP baseline MTU. + +Some controllers may also use this as the maximum receive unit size, and +may not accept MCTP messages larger than the configured MTU. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_mi_config_set_mctp_mtu (nvme_mi_ep_t ep, __u8 port, __u16 mtu) + + set configuration: MCTP MTU + +**Parameters** + +``nvme_mi_ep_t ep`` + endpoint for MI communication + +``__u8 port`` + port ID to set + +``__u16 mtu`` + new MTU configuration + +**Description** + +Performs a MI Configuration Set, to update the current MCTP MTU value for +the port specified in **port**. + +Some controllers may also use this as the maximum receive unit size, and +may not accept MCTP messages larger than the configured MTU. When setting +this value, you will likely need to change the MTU of the local MCTP +interface(s) to match. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_admin_xfer (nvme_mi_ctrl_t ctrl, struct nvme_mi_admin_req_hdr *admin_req, size_t req_data_size, struct nvme_mi_admin_resp_hdr *admin_resp, off_t resp_data_offset, size_t *resp_data_size) + + Raw admin transfer interface. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + controller to send the admin command to + +``struct nvme_mi_admin_req_hdr *admin_req`` + request data + +``size_t req_data_size`` + size of request data payload + +``struct nvme_mi_admin_resp_hdr *admin_resp`` + buffer for response data + +``off_t resp_data_offset`` + offset into request data to retrieve from controller + +``size_t *resp_data_size`` + size of response data buffer, updated to received size + +**Description** + +Performs an arbitrary NVMe Admin command, using the provided request data, +in **admin_req**. The size of the request data *payload* is specified in +**req_data_size** - this does not include the standard header length (so a +header-only request would have a size of 0). + +On success, response data is stored in **admin_resp**, which has an optional +appended payload buffer of **resp_data_size** bytes. The actual payload +transferred will be stored in **resp_data_size**. These sizes do not include +the Admin request header, so 0 represents no payload. + +As with all Admin commands, we can request partial data from the Admin +Response payload, offset by **resp_data_offset**. + +See: :c:type:`struct nvme_mi_admin_req_hdr <nvme_mi_admin_req_hdr>` and :c:type:`struct nvme_mi_admin_resp_hdr <nvme_mi_admin_resp_hdr>`. + +**Return** + +0 on success, non-zero on failure. + + +.. c:function:: int nvme_mi_admin_identify_partial (nvme_mi_ctrl_t ctrl, struct nvme_identify_args *args, off_t offset, size_t size) + + Perform an Admin identify command, and retrieve partial response data. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to process identify command + +``struct nvme_identify_args *args`` + Identify command arguments + +``off_t offset`` + offset of identify data to retrieve from response + +``size_t size`` + size of identify data to return + +**Description** + +Perform an Identify command, using the Identify command parameters in **args**. +The **offset** and **size** arguments allow the caller to retrieve part of +the identify response. See NVMe-MI section 6.2 for the semantics (and some +handy diagrams) of the offset & size parameters. + +Will return an error if the length of the response data (from the controller) +did not match **size**. + +Unless you're performing a vendor-unique identify command, You'll probably +want to use one of the identify helpers (nvme_mi_admin_identify, +nvme_mi_admin_identify_cns_nsid, or nvme_mi_admin_identify_<type>) instead +of this. If the type of your identify command is standardized but not +yet supported by libnvme-mi, please contact the maintainers. + +See: :c:type:`struct nvme_identify_args <nvme_identify_args>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_identify (nvme_mi_ctrl_t ctrl, struct nvme_identify_args *args) + + Perform an Admin identify command. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to process identify command + +``struct nvme_identify_args *args`` + Identify command arguments + +**Description** + +Perform an Identify command, using the Identify command parameters in **args**. +Stores the identify data in ->data, and (if set) the result from cdw0 +into args->result. + +Will return an error if the length of the response data (from the +controller) is not a full :c:type:`NVME_IDENTIFY_DATA_SIZE`. + +See: :c:type:`struct nvme_identify_args <nvme_identify_args>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_identify_cns_nsid (nvme_mi_ctrl_t ctrl, enum nvme_identify_cns cns, __u32 nsid, void *data) + + Perform an Admin identify command using specific CNS/NSID parameters. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to process identify command + +``enum nvme_identify_cns cns`` + Controller or Namespace Structure, specifying identified object + +``__u32 nsid`` + namespace ID + +``void *data`` + buffer for identify data response + +**Description** + +Perform an Identify command, using the CNS specifier **cns**, and the +namespace ID **nsid** if required by the CNS type. + +Stores the identify data in **data**, which is expected to be a buffer of +:c:type:`NVME_IDENTIFY_DATA_SIZE` bytes. + +Will return an error if the length of the response data (from the +controller) is not a full :c:type:`NVME_IDENTIFY_DATA_SIZE`. + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_identify_ctrl (nvme_mi_ctrl_t ctrl, struct nvme_id_ctrl *id) + + Perform an Admin identify for a controller + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to process identify command + +``struct nvme_id_ctrl *id`` + Controller identify data to populate + +**Description** + +Perform an Identify command, for the controller specified by **ctrl**, +writing identify data to **id**. + +Will return an error if the length of the response data (from the +controller) is not a full :c:type:`NVME_IDENTIFY_DATA_SIZE`, so **id** will be +fully populated on success. + +See: :c:type:`struct nvme_id_ctrl <nvme_id_ctrl>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_identify_ctrl_list (nvme_mi_ctrl_t ctrl, __u16 cntid, struct nvme_ctrl_list *list) + + Perform an Admin identify for a controller list. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to process identify command + +``__u16 cntid`` + Controller ID to specify list start + +``struct nvme_ctrl_list *list`` + List data to populate + +**Description** + +Perform an Identify command, for the controller list starting with +IDs greater than or equal to **cntid**. + +Will return an error if the length of the response data (from the +controller) is not a full :c:type:`NVME_IDENTIFY_DATA_SIZE`, so **id** will be +fully populated on success. + +See: :c:type:`struct nvme_ctrl_list <nvme_ctrl_list>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_get_log_page (nvme_mi_ctrl_t ctrl, struct nvme_get_log_args *args) + + Retrieve log page data from controller + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to query + +``struct nvme_get_log_args *args`` + Get Log Page command arguments + +**Description** + +Performs a Get Log Page Admin command as specified by **args**. Response data +is stored in **args->data**, which should be a buffer of **args->data_len** bytes. +Resulting data length is stored in **args->data_len** on successful +command completion. + +This request may be implemented as multiple log page commands, in order +to fit within MI message-size limits. + +See: :c:type:`struct nvme_get_log_args <nvme_get_log_args>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_security_send (nvme_mi_ctrl_t ctrl, struct nvme_security_send_args *args) + + Perform a Security Send command on a controller. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to send command to + +``struct nvme_security_send_args *args`` + Security Send command arguments + +**Description** + +Performs a Security Send Admin command as specified by **args**. Response data +is stored in **args->data**, which should be a buffer of **args->data_len** bytes. +Resulting data length is stored in **args->data_len** on successful +command completion. + +Security Send data length should not be greater than 4096 bytes to +comply with specification limits. + +See: :c:type:`struct nvme_get_log_args <nvme_get_log_args>` + +**Return** + +0 on success, non-zero on failure + + +.. c:function:: int nvme_mi_admin_security_recv (nvme_mi_ctrl_t ctrl, struct nvme_security_receive_args *args) + + Perform a Security Receive command on a controller. + +**Parameters** + +``nvme_mi_ctrl_t ctrl`` + Controller to send command to + +``struct nvme_security_receive_args *args`` + Security Receive command arguments + +**Description** + +Performs a Security Receive Admin command as specified by **args**. Response +data is stored in **args->data**, which should be a buffer of **args->data_len** +bytes. Resulting data length is stored in **args->data_len** on successful +command completion. + +Security Receive data length should not be greater than 4096 bytes to +comply with specification limits. + +See: :c:type:`struct nvme_get_log_args <nvme_get_log_args>` + +**Return** + +0 on success, non-zero on failure + + |