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| -rw-r--r-- | include/linux/nvme-fc-driver.h | 1045 |
1 files changed, 1045 insertions, 0 deletions
diff --git a/include/linux/nvme-fc-driver.h b/include/linux/nvme-fc-driver.h new file mode 100644 index 000000000..2a38f2b47 --- /dev/null +++ b/include/linux/nvme-fc-driver.h @@ -0,0 +1,1045 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2016, Avago Technologies + */ + +#ifndef _NVME_FC_DRIVER_H +#define _NVME_FC_DRIVER_H 1 + +#include <linux/scatterlist.h> + + +/* + * ********************** FC-NVME LS API ******************** + * + * Data structures used by both FC-NVME hosts and FC-NVME + * targets to perform FC-NVME LS requests or transmit + * responses. + * + * *********************************************************** + */ + +/** + * struct nvmefc_ls_req - Request structure passed from the transport + * to the LLDD to perform a NVME-FC LS request and obtain + * a response. + * Used by nvme-fc transport (host) to send LS's such as + * Create Association, Create Connection and Disconnect + * Association. + * Used by the nvmet-fc transport (controller) to send + * LS's such as Disconnect Association. + * + * Values set by the requestor prior to calling the LLDD ls_req entrypoint: + * @rqstaddr: pointer to request buffer + * @rqstdma: PCI DMA address of request buffer + * @rqstlen: Length, in bytes, of request buffer + * @rspaddr: pointer to response buffer + * @rspdma: PCI DMA address of response buffer + * @rsplen: Length, in bytes, of response buffer + * @timeout: Maximum amount of time, in seconds, to wait for the LS response. + * If timeout exceeded, LLDD to abort LS exchange and complete + * LS request with error status. + * @private: pointer to memory allocated alongside the ls request structure + * that is specifically for the LLDD to use while processing the + * request. The length of the buffer corresponds to the + * lsrqst_priv_sz value specified in the xxx_template supplied + * by the LLDD. + * @done: The callback routine the LLDD is to invoke upon completion of + * the LS request. req argument is the pointer to the original LS + * request structure. Status argument must be 0 upon success, a + * negative errno on failure (example: -ENXIO). + */ +struct nvmefc_ls_req { + void *rqstaddr; + dma_addr_t rqstdma; + u32 rqstlen; + void *rspaddr; + dma_addr_t rspdma; + u32 rsplen; + u32 timeout; + + void *private; + + void (*done)(struct nvmefc_ls_req *req, int status); + +} __aligned(sizeof(u64)); /* alignment for other things alloc'd with */ + + +/** + * struct nvmefc_ls_rsp - Structure passed from the transport to the LLDD + * to request the transmit the NVME-FC LS response to a + * NVME-FC LS request. The structure originates in the LLDD + * and is given to the transport via the xxx_rcv_ls_req() + * transport routine. As such, the structure represents the + * FC exchange context for the NVME-FC LS request that was + * received and which the response is to be sent for. + * Used by the LLDD to pass the nvmet-fc transport (controller) + * received LS's such as Create Association, Create Connection + * and Disconnect Association. + * Used by the LLDD to pass the nvme-fc transport (host) + * received LS's such as Disconnect Association or Disconnect + * Connection. + * + * The structure is allocated by the LLDD whenever a LS Request is received + * from the FC link. The address of the structure is passed to the nvmet-fc + * or nvme-fc layer via the xxx_rcv_ls_req() transport routines. + * + * The address of the structure is to be passed back to the LLDD + * when the response is to be transmit. The LLDD will use the address to + * map back to the LLDD exchange structure which maintains information such + * the remote N_Port that sent the LS as well as any FC exchange context. + * Upon completion of the LS response transmit, the LLDD will pass the + * address of the structure back to the transport LS rsp done() routine, + * allowing the transport release dma resources. Upon completion of + * the done() routine, no further access to the structure will be made by + * the transport and the LLDD can de-allocate the structure. + * + * Field initialization: + * At the time of the xxx_rcv_ls_req() call, there is no content that + * is valid in the structure. + * + * When the structure is used for the LLDD->xmt_ls_rsp() call, the + * transport layer will fully set the fields in order to specify the + * response payload buffer and its length as well as the done routine + * to be called upon completion of the transmit. The transport layer + * will also set a private pointer for its own use in the done routine. + * + * Values set by the transport layer prior to calling the LLDD xmt_ls_rsp + * entrypoint: + * @rspbuf: pointer to the LS response buffer + * @rspdma: PCI DMA address of the LS response buffer + * @rsplen: Length, in bytes, of the LS response buffer + * @done: The callback routine the LLDD is to invoke upon completion of + * transmitting the LS response. req argument is the pointer to + * the original ls request. + * @nvme_fc_private: pointer to an internal transport-specific structure + * used as part of the transport done() processing. The LLDD is + * not to access this pointer. + */ +struct nvmefc_ls_rsp { + void *rspbuf; + dma_addr_t rspdma; + u16 rsplen; + + void (*done)(struct nvmefc_ls_rsp *rsp); + void *nvme_fc_private; /* LLDD is not to access !! */ +}; + + + +/* + * ********************** LLDD FC-NVME Host API ******************** + * + * For FC LLDD's that are the NVME Host role. + * + * ****************************************************************** + */ + + +/** + * struct nvme_fc_port_info - port-specific ids and FC connection-specific + * data element used during NVME Host role + * registrations + * + * Static fields describing the port being registered: + * @node_name: FC WWNN for the port + * @port_name: FC WWPN for the port + * @port_role: What NVME roles are supported (see FC_PORT_ROLE_xxx) + * @dev_loss_tmo: maximum delay for reconnects to an association on + * this device. Used only on a remoteport. + * + * Initialization values for dynamic port fields: + * @port_id: FC N_Port_ID currently assigned the port. Upper 8 bits must + * be set to 0. + */ +struct nvme_fc_port_info { + u64 node_name; + u64 port_name; + u32 port_role; + u32 port_id; + u32 dev_loss_tmo; +}; + +enum nvmefc_fcp_datadir { + NVMEFC_FCP_NODATA, /* payload_length and sg_cnt will be zero */ + NVMEFC_FCP_WRITE, + NVMEFC_FCP_READ, +}; + + +/** + * struct nvmefc_fcp_req - Request structure passed from NVME-FC transport + * to LLDD in order to perform a NVME FCP IO operation. + * + * Values set by the NVME-FC layer prior to calling the LLDD fcp_io + * entrypoint. + * @cmdaddr: pointer to the FCP CMD IU buffer + * @rspaddr: pointer to the FCP RSP IU buffer + * @cmddma: PCI DMA address of the FCP CMD IU buffer + * @rspdma: PCI DMA address of the FCP RSP IU buffer + * @cmdlen: Length, in bytes, of the FCP CMD IU buffer + * @rsplen: Length, in bytes, of the FCP RSP IU buffer + * @payload_length: Length of DATA_IN or DATA_OUT payload data to transfer + * @sg_table: scatter/gather structure for payload data + * @first_sgl: memory for 1st scatter/gather list segment for payload data + * @sg_cnt: number of elements in the scatter/gather list + * @io_dir: direction of the FCP request (see NVMEFC_FCP_xxx) + * @sqid: The nvme SQID the command is being issued on + * @done: The callback routine the LLDD is to invoke upon completion of + * the FCP operation. req argument is the pointer to the original + * FCP IO operation. + * @private: pointer to memory allocated alongside the FCP operation + * request structure that is specifically for the LLDD to use + * while processing the operation. The length of the buffer + * corresponds to the fcprqst_priv_sz value specified in the + * nvme_fc_port_template supplied by the LLDD. + * + * Values set by the LLDD indicating completion status of the FCP operation. + * Must be set prior to calling the done() callback. + * @transferred_length: amount of payload data, in bytes, that were + * transferred. Should equal payload_length on success. + * @rcv_rsplen: length, in bytes, of the FCP RSP IU received. + * @status: Completion status of the FCP operation. must be 0 upon success, + * negative errno value upon failure (ex: -EIO). Note: this is + * NOT a reflection of the NVME CQE completion status. Only the + * status of the FCP operation at the NVME-FC level. + */ +struct nvmefc_fcp_req { + void *cmdaddr; + void *rspaddr; + dma_addr_t cmddma; + dma_addr_t rspdma; + u16 cmdlen; + u16 rsplen; + + u32 payload_length; + struct sg_table sg_table; + struct scatterlist *first_sgl; + int sg_cnt; + enum nvmefc_fcp_datadir io_dir; + + __le16 sqid; + + void (*done)(struct nvmefc_fcp_req *req); + + void *private; + + u32 transferred_length; + u16 rcv_rsplen; + u32 status; +} __aligned(sizeof(u64)); /* alignment for other things alloc'd with */ + + +/* + * Direct copy of fc_port_state enum. For later merging + */ +enum nvme_fc_obj_state { + FC_OBJSTATE_UNKNOWN, + FC_OBJSTATE_NOTPRESENT, + FC_OBJSTATE_ONLINE, + FC_OBJSTATE_OFFLINE, /* User has taken Port Offline */ + FC_OBJSTATE_BLOCKED, + FC_OBJSTATE_BYPASSED, + FC_OBJSTATE_DIAGNOSTICS, + FC_OBJSTATE_LINKDOWN, + FC_OBJSTATE_ERROR, + FC_OBJSTATE_LOOPBACK, + FC_OBJSTATE_DELETED, +}; + + +/** + * struct nvme_fc_local_port - structure used between NVME-FC transport and + * a LLDD to reference a local NVME host port. + * Allocated/created by the nvme_fc_register_localport() + * transport interface. + * + * Fields with static values for the port. Initialized by the + * port_info struct supplied to the registration call. + * @port_num: NVME-FC transport host port number + * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx) + * @node_name: FC WWNN for the port + * @port_name: FC WWPN for the port + * @private: pointer to memory allocated alongside the local port + * structure that is specifically for the LLDD to use. + * The length of the buffer corresponds to the local_priv_sz + * value specified in the nvme_fc_port_template supplied by + * the LLDD. + * @dev_loss_tmo: maximum delay for reconnects to an association on + * this device. To modify, lldd must call + * nvme_fc_set_remoteport_devloss(). + * + * Fields with dynamic values. Values may change base on link state. LLDD + * may reference fields directly to change them. Initialized by the + * port_info struct supplied to the registration call. + * @port_id: FC N_Port_ID currently assigned the port. Upper 8 bits must + * be set to 0. + * @port_state: Operational state of the port. + */ +struct nvme_fc_local_port { + /* static/read-only fields */ + u32 port_num; + u32 port_role; + u64 node_name; + u64 port_name; + + void *private; + + /* dynamic fields */ + u32 port_id; + enum nvme_fc_obj_state port_state; +} __aligned(sizeof(u64)); /* alignment for other things alloc'd with */ + + +/** + * struct nvme_fc_remote_port - structure used between NVME-FC transport and + * a LLDD to reference a remote NVME subsystem port. + * Allocated/created by the nvme_fc_register_remoteport() + * transport interface. + * + * Fields with static values for the port. Initialized by the + * port_info struct supplied to the registration call. + * @port_num: NVME-FC transport remote subsystem port number + * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx) + * @node_name: FC WWNN for the port + * @port_name: FC WWPN for the port + * @localport: pointer to the NVME-FC local host port the subsystem is + * connected to. + * @private: pointer to memory allocated alongside the remote port + * structure that is specifically for the LLDD to use. + * The length of the buffer corresponds to the remote_priv_sz + * value specified in the nvme_fc_port_template supplied by + * the LLDD. + * + * Fields with dynamic values. Values may change base on link or login + * state. LLDD may reference fields directly to change them. Initialized by + * the port_info struct supplied to the registration call. + * @port_id: FC N_Port_ID currently assigned the port. Upper 8 bits must + * be set to 0. + * @port_state: Operational state of the remote port. Valid values are + * ONLINE or UNKNOWN. + */ +struct nvme_fc_remote_port { + /* static fields */ + u32 port_num; + u32 port_role; + u64 node_name; + u64 port_name; + struct nvme_fc_local_port *localport; + void *private; + u32 dev_loss_tmo; + + /* dynamic fields */ + u32 port_id; + enum nvme_fc_obj_state port_state; +} __aligned(sizeof(u64)); /* alignment for other things alloc'd with */ + + +/** + * struct nvme_fc_port_template - structure containing static entrypoints and + * operational parameters for an LLDD that supports NVME host + * behavior. Passed by reference in port registrations. + * NVME-FC transport remembers template reference and may + * access it during runtime operation. + * + * Host/Initiator Transport Entrypoints/Parameters: + * + * @localport_delete: The LLDD initiates deletion of a localport via + * nvme_fc_deregister_localport(). However, the teardown is + * asynchronous. This routine is called upon the completion of the + * teardown to inform the LLDD that the localport has been deleted. + * Entrypoint is Mandatory. + * + * @remoteport_delete: The LLDD initiates deletion of a remoteport via + * nvme_fc_deregister_remoteport(). However, the teardown is + * asynchronous. This routine is called upon the completion of the + * teardown to inform the LLDD that the remoteport has been deleted. + * Entrypoint is Mandatory. + * + * @create_queue: Upon creating a host<->controller association, queues are + * created such that they can be affinitized to cpus/cores. This + * callback into the LLDD to notify that a controller queue is being + * created. The LLDD may choose to allocate an associated hw queue + * or map it onto a shared hw queue. Upon return from the call, the + * LLDD specifies a handle that will be given back to it for any + * command that is posted to the controller queue. The handle can + * be used by the LLDD to map quickly to the proper hw queue for + * command execution. The mask of cpu's that will map to this queue + * at the block-level is also passed in. The LLDD should use the + * queue id and/or cpu masks to ensure proper affinitization of the + * controller queue to the hw queue. + * Entrypoint is Optional. + * + * @delete_queue: This is the inverse of the crete_queue. During + * host<->controller association teardown, this routine is called + * when a controller queue is being terminated. Any association with + * a hw queue should be termined. If there is a unique hw queue, the + * hw queue should be torn down. + * Entrypoint is Optional. + * + * @poll_queue: Called to poll for the completion of an io on a blk queue. + * Entrypoint is Optional. + * + * @ls_req: Called to issue a FC-NVME FC-4 LS service request. + * The nvme_fc_ls_req structure will fully describe the buffers for + * the request payload and where to place the response payload. The + * LLDD is to allocate an exchange, issue the LS request, obtain the + * LS response, and call the "done" routine specified in the request + * structure (argument to done is the ls request structure itself). + * Entrypoint is Mandatory. + * + * @fcp_io: called to issue a FC-NVME I/O request. The I/O may be for + * an admin queue or an i/o queue. The nvmefc_fcp_req structure will + * fully describe the io: the buffer containing the FC-NVME CMD IU + * (which contains the SQE), the sg list for the payload if applicable, + * and the buffer to place the FC-NVME RSP IU into. The LLDD will + * complete the i/o, indicating the amount of data transferred or + * any transport error, and call the "done" routine specified in the + * request structure (argument to done is the fcp request structure + * itself). + * Entrypoint is Mandatory. + * + * @ls_abort: called to request the LLDD to abort the indicated ls request. + * The call may return before the abort has completed. After aborting + * the request, the LLDD must still call the ls request done routine + * indicating an FC transport Aborted status. + * Entrypoint is Mandatory. + * + * @fcp_abort: called to request the LLDD to abort the indicated fcp request. + * The call may return before the abort has completed. After aborting + * the request, the LLDD must still call the fcp request done routine + * indicating an FC transport Aborted status. + * Entrypoint is Mandatory. + * + * @xmt_ls_rsp: Called to transmit the response to a FC-NVME FC-4 LS service. + * The nvmefc_ls_rsp structure is the same LLDD-supplied exchange + * structure specified in the nvme_fc_rcv_ls_req() call made when + * the LS request was received. The structure will fully describe + * the buffers for the response payload and the dma address of the + * payload. The LLDD is to transmit the response (or return a + * non-zero errno status), and upon completion of the transmit, call + * the "done" routine specified in the nvmefc_ls_rsp structure + * (argument to done is the address of the nvmefc_ls_rsp structure + * itself). Upon the completion of the done routine, the LLDD shall + * consider the LS handling complete and the nvmefc_ls_rsp structure + * may be freed/released. + * Entrypoint is mandatory if the LLDD calls the nvme_fc_rcv_ls_req() + * entrypoint. + * + * @max_hw_queues: indicates the maximum number of hw queues the LLDD + * supports for cpu affinitization. + * Value is Mandatory. Must be at least 1. + * + * @max_sgl_segments: indicates the maximum number of sgl segments supported + * by the LLDD + * Value is Mandatory. Must be at least 1. Recommend at least 256. + * + * @max_dif_sgl_segments: indicates the maximum number of sgl segments + * supported by the LLDD for DIF operations. + * Value is Mandatory. Must be at least 1. Recommend at least 256. + * + * @dma_boundary: indicates the dma address boundary where dma mappings + * will be split across. + * Value is Mandatory. Typical value is 0xFFFFFFFF to split across + * 4Gig address boundarys + * + * @local_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like fc nvme layer to allocate on the LLDD's + * behalf whenever a localport is allocated. The additional memory + * area solely for the of the LLDD and its location is specified by + * the localport->private pointer. + * Value is Mandatory. Allowed to be zero. + * + * @remote_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like fc nvme layer to allocate on the LLDD's + * behalf whenever a remoteport is allocated. The additional memory + * area solely for the of the LLDD and its location is specified by + * the remoteport->private pointer. + * Value is Mandatory. Allowed to be zero. + * + * @lsrqst_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like fc nvme layer to allocate on the LLDD's + * behalf whenever a ls request structure is allocated. The additional + * memory area is solely for use by the LLDD and its location is + * specified by the ls_request->private pointer. + * Value is Mandatory. Allowed to be zero. + * + * @fcprqst_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like fc nvme layer to allocate on the LLDD's + * behalf whenever a fcp request structure is allocated. The additional + * memory area solely for the of the LLDD and its location is + * specified by the fcp_request->private pointer. + * Value is Mandatory. Allowed to be zero. + */ +struct nvme_fc_port_template { + /* initiator-based functions */ + void (*localport_delete)(struct nvme_fc_local_port *); + void (*remoteport_delete)(struct nvme_fc_remote_port *); + int (*create_queue)(struct nvme_fc_local_port *, + unsigned int qidx, u16 qsize, + void **handle); + void (*delete_queue)(struct nvme_fc_local_port *, + unsigned int qidx, void *handle); + int (*ls_req)(struct nvme_fc_local_port *, + struct nvme_fc_remote_port *, + struct nvmefc_ls_req *); + int (*fcp_io)(struct nvme_fc_local_port *, + struct nvme_fc_remote_port *, + void *hw_queue_handle, + struct nvmefc_fcp_req *); + void (*ls_abort)(struct nvme_fc_local_port *, + struct nvme_fc_remote_port *, + struct nvmefc_ls_req *); + void (*fcp_abort)(struct nvme_fc_local_port *, + struct nvme_fc_remote_port *, + void *hw_queue_handle, + struct nvmefc_fcp_req *); + int (*xmt_ls_rsp)(struct nvme_fc_local_port *localport, + struct nvme_fc_remote_port *rport, + struct nvmefc_ls_rsp *ls_rsp); + + u32 max_hw_queues; + u16 max_sgl_segments; + u16 max_dif_sgl_segments; + u64 dma_boundary; + + /* sizes of additional private data for data structures */ + u32 local_priv_sz; + u32 remote_priv_sz; + u32 lsrqst_priv_sz; + u32 fcprqst_priv_sz; +}; + + +/* + * Initiator/Host functions + */ + +int nvme_fc_register_localport(struct nvme_fc_port_info *pinfo, + struct nvme_fc_port_template *template, + struct device *dev, + struct nvme_fc_local_port **lport_p); + +int nvme_fc_unregister_localport(struct nvme_fc_local_port *localport); + +int nvme_fc_register_remoteport(struct nvme_fc_local_port *localport, + struct nvme_fc_port_info *pinfo, + struct nvme_fc_remote_port **rport_p); + +int nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *remoteport); + +void nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport); + +int nvme_fc_set_remoteport_devloss(struct nvme_fc_remote_port *remoteport, + u32 dev_loss_tmo); + +/* + * Routine called to pass a NVME-FC LS request, received by the lldd, + * to the nvme-fc transport. + * + * If the return value is zero: the LS was successfully accepted by the + * transport. + * If the return value is non-zero: the transport has not accepted the + * LS. The lldd should ABTS-LS the LS. + * + * Note: if the LLDD receives and ABTS for the LS prior to the transport + * calling the ops->xmt_ls_rsp() routine to transmit a response, the LLDD + * shall mark the LS as aborted, and when the xmt_ls_rsp() is called: the + * response shall not be transmit and the struct nvmefc_ls_rsp() done + * routine shall be called. The LLDD may transmit the ABTS response as + * soon as the LS was marked or can delay until the xmt_ls_rsp() call is + * made. + * Note: if an RCV LS was successfully posted to the transport and the + * remoteport is then unregistered before xmt_ls_rsp() was called for + * the lsrsp structure, the transport will still call xmt_ls_rsp() + * afterward to cleanup the outstanding lsrsp structure. The LLDD should + * noop the transmission of the rsp and call the lsrsp->done() routine + * to allow the lsrsp structure to be released. + */ +int nvme_fc_rcv_ls_req(struct nvme_fc_remote_port *remoteport, + struct nvmefc_ls_rsp *lsrsp, + void *lsreqbuf, u32 lsreqbuf_len); + + + +/* + * *************** LLDD FC-NVME Target/Subsystem API *************** + * + * For FC LLDD's that are the NVME Subsystem role + * + * ****************************************************************** + */ + +/** + * struct nvmet_fc_port_info - port-specific ids and FC connection-specific + * data element used during NVME Subsystem role + * registrations + * + * Static fields describing the port being registered: + * @node_name: FC WWNN for the port + * @port_name: FC WWPN for the port + * + * Initialization values for dynamic port fields: + * @port_id: FC N_Port_ID currently assigned the port. Upper 8 bits must + * be set to 0. + */ +struct nvmet_fc_port_info { + u64 node_name; + u64 port_name; + u32 port_id; +}; + + +/* Operations that NVME-FC layer may request the LLDD to perform for FCP */ +enum { + NVMET_FCOP_READDATA = 1, /* xmt data to initiator */ + NVMET_FCOP_WRITEDATA = 2, /* xmt data from initiator */ + NVMET_FCOP_READDATA_RSP = 3, /* xmt data to initiator and send + * rsp as well + */ + NVMET_FCOP_RSP = 4, /* send rsp frame */ +}; + +/** + * struct nvmefc_tgt_fcp_req - Structure used between LLDD and NVMET-FC + * layer to represent the exchange context and + * the specific FC-NVME IU operation(s) to perform + * for a FC-NVME FCP IO. + * + * Structure used between LLDD and nvmet-fc layer to represent the exchange + * context for a FC-NVME FCP I/O operation (e.g. a nvme sqe, the sqe-related + * memory transfers, and its assocated cqe transfer). + * + * The structure is allocated by the LLDD whenever a FCP CMD IU is received + * from the FC link. The address of the structure is passed to the nvmet-fc + * layer via the nvmet_fc_rcv_fcp_req() call. The address of the structure + * will be passed back to the LLDD for the data operations and transmit of + * the response. The LLDD is to use the address to map back to the LLDD + * exchange structure which maintains information such as the targetport + * the FCP I/O was received on, the remote FC NVME initiator that sent the + * FCP I/O, and any FC exchange context. Upon completion of the FCP target + * operation, the address of the structure will be passed back to the FCP + * op done() routine, allowing the nvmet-fc layer to release dma resources. + * Upon completion of the done() routine for either RSP or ABORT ops, no + * further access will be made by the nvmet-fc layer and the LLDD can + * de-allocate the structure. + * + * Field initialization: + * At the time of the nvmet_fc_rcv_fcp_req() call, there is no content that + * is valid in the structure. + * + * When the structure is used for an FCP target operation, the nvmet-fc + * layer will fully set the fields in order to specify the scattergather + * list, the transfer length, as well as the done routine to be called + * upon compeletion of the operation. The nvmet-fc layer will also set a + * private pointer for its own use in the done routine. + * + * Values set by the NVMET-FC layer prior to calling the LLDD fcp_op + * entrypoint. + * @op: Indicates the FCP IU operation to perform (see NVMET_FCOP_xxx) + * @hwqid: Specifies the hw queue index (0..N-1, where N is the + * max_hw_queues value from the LLD's nvmet_fc_target_template) + * that the operation is to use. + * @offset: Indicates the DATA_OUT/DATA_IN payload offset to be tranferred. + * Field is only valid on WRITEDATA, READDATA, or READDATA_RSP ops. + * @timeout: amount of time, in seconds, to wait for a response from the NVME + * host. A value of 0 is an infinite wait. + * Valid only for the following ops: + * WRITEDATA: caps the wait for data reception + * READDATA_RSP & RSP: caps wait for FCP_CONF reception (if used) + * @transfer_length: the length, in bytes, of the DATA_OUT or DATA_IN payload + * that is to be transferred. + * Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops. + * @ba_rjt: Contains the BA_RJT payload that is to be transferred. + * Valid only for the NVMET_FCOP_BA_RJT op. + * @sg: Scatter/gather list for the DATA_OUT/DATA_IN payload data. + * Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops. + * @sg_cnt: Number of valid entries in the scatter/gather list. + * Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops. + * @rspaddr: pointer to the FCP RSP IU buffer to be transmit + * Used by RSP and READDATA_RSP ops + * @rspdma: PCI DMA address of the FCP RSP IU buffer + * Used by RSP and READDATA_RSP ops + * @rsplen: Length, in bytes, of the FCP RSP IU buffer + * Used by RSP and READDATA_RSP ops + * @done: The callback routine the LLDD is to invoke upon completion of + * the operation. req argument is the pointer to the original + * FCP subsystem op request. + * @nvmet_fc_private: pointer to an internal NVMET-FC layer structure used + * as part of the NVMET-FC processing. The LLDD is not to + * reference this field. + * + * Values set by the LLDD indicating completion status of the FCP operation. + * Must be set prior to calling the done() callback. + * @transferred_length: amount of DATA_OUT payload data received by a + * WRITEDATA operation. If not a WRITEDATA operation, value must + * be set to 0. Should equal transfer_length on success. + * @fcp_error: status of the FCP operation. Must be 0 on success; on failure + * must be a NVME_SC_FC_xxxx value. + */ +struct nvmefc_tgt_fcp_req { + u8 op; + u16 hwqid; + u32 offset; + u32 timeout; + u32 transfer_length; + struct fc_ba_rjt ba_rjt; + struct scatterlist *sg; + int sg_cnt; + void *rspaddr; + dma_addr_t rspdma; + u16 rsplen; + + void (*done)(struct nvmefc_tgt_fcp_req *); + + void *nvmet_fc_private; /* LLDD is not to access !! */ + + u32 transferred_length; + int fcp_error; +}; + + +/* Target Features (Bit fields) LLDD supports */ +enum { + NVMET_FCTGTFEAT_READDATA_RSP = (1 << 0), + /* Bit 0: supports the NVMET_FCPOP_READDATA_RSP op, which + * sends (the last) Read Data sequence followed by the RSP + * sequence in one LLDD operation. Errors during Data + * sequence transmit must not allow RSP sequence to be sent. + */ +}; + + +/** + * struct nvmet_fc_target_port - structure used between NVME-FC transport and + * a LLDD to reference a local NVME subsystem port. + * Allocated/created by the nvme_fc_register_targetport() + * transport interface. + * + * Fields with static values for the port. Initialized by the + * port_info struct supplied to the registration call. + * @port_num: NVME-FC transport subsytem port number + * @node_name: FC WWNN for the port + * @port_name: FC WWPN for the port + * @private: pointer to memory allocated alongside the local port + * structure that is specifically for the LLDD to use. + * The length of the buffer corresponds to the target_priv_sz + * value specified in the nvme_fc_target_template supplied by + * the LLDD. + * + * Fields with dynamic values. Values may change base on link state. LLDD + * may reference fields directly to change them. Initialized by the + * port_info struct supplied to the registration call. + * @port_id: FC N_Port_ID currently assigned the port. Upper 8 bits must + * be set to 0. + * @port_state: Operational state of the port. + */ +struct nvmet_fc_target_port { + /* static/read-only fields */ + u32 port_num; + u64 node_name; + u64 port_name; + + void *private; + + /* dynamic fields */ + u32 port_id; + enum nvme_fc_obj_state port_state; +} __aligned(sizeof(u64)); /* alignment for other things alloc'd with */ + + +/** + * struct nvmet_fc_target_template - structure containing static entrypoints + * and operational parameters for an LLDD that supports NVME + * subsystem behavior. Passed by reference in port + * registrations. NVME-FC transport remembers template + * reference and may access it during runtime operation. + * + * Subsystem/Target Transport Entrypoints/Parameters: + * + * @targetport_delete: The LLDD initiates deletion of a targetport via + * nvmet_fc_unregister_targetport(). However, the teardown is + * asynchronous. This routine is called upon the completion of the + * teardown to inform the LLDD that the targetport has been deleted. + * Entrypoint is Mandatory. + * + * @xmt_ls_rsp: Called to transmit the response to a FC-NVME FC-4 LS service. + * The nvmefc_ls_rsp structure is the same LLDD-supplied exchange + * structure specified in the nvmet_fc_rcv_ls_req() call made when + * the LS request was received. The structure will fully describe + * the buffers for the response payload and the dma address of the + * payload. The LLDD is to transmit the response (or return a + * non-zero errno status), and upon completion of the transmit, call + * the "done" routine specified in the nvmefc_ls_rsp structure + * (argument to done is the address of the nvmefc_ls_rsp structure + * itself). Upon the completion of the done() routine, the LLDD shall + * consider the LS handling complete and the nvmefc_ls_rsp structure + * may be freed/released. + * The transport will always call the xmt_ls_rsp() routine for any + * LS received. + * Entrypoint is Mandatory. + * + * @fcp_op: Called to perform a data transfer or transmit a response. + * The nvmefc_tgt_fcp_req structure is the same LLDD-supplied + * exchange structure specified in the nvmet_fc_rcv_fcp_req() call + * made when the FCP CMD IU was received. The op field in the + * structure shall indicate the operation for the LLDD to perform + * relative to the io. + * NVMET_FCOP_READDATA operation: the LLDD is to send the + * payload data (described by sglist) to the host in 1 or + * more FC sequences (preferrably 1). Note: the fc-nvme layer + * may call the READDATA operation multiple times for longer + * payloads. + * NVMET_FCOP_WRITEDATA operation: the LLDD is to receive the + * payload data (described by sglist) from the host via 1 or + * more FC sequences (preferrably 1). The LLDD is to generate + * the XFER_RDY IU(s) corresponding to the data being requested. + * Note: the FC-NVME layer may call the WRITEDATA operation + * multiple times for longer payloads. + * NVMET_FCOP_READDATA_RSP operation: the LLDD is to send the + * payload data (described by sglist) to the host in 1 or + * more FC sequences (preferrably 1). If an error occurs during + * payload data transmission, the LLDD is to set the + * nvmefc_tgt_fcp_req fcp_error and transferred_length field, then + * consider the operation complete. On error, the LLDD is to not + * transmit the FCP_RSP iu. If all payload data is transferred + * successfully, the LLDD is to update the nvmefc_tgt_fcp_req + * transferred_length field and may subsequently transmit the + * FCP_RSP iu payload (described by rspbuf, rspdma, rsplen). + * If FCP_CONF is supported, the LLDD is to await FCP_CONF + * reception to confirm the RSP reception by the host. The LLDD + * may retramsit the FCP_RSP iu if necessary per FC-NVME. Upon + * transmission of the FCP_RSP iu if FCP_CONF is not supported, + * or upon success/failure of FCP_CONF if it is supported, the + * LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and + * consider the operation complete. + * NVMET_FCOP_RSP: the LLDD is to transmit the FCP_RSP iu payload + * (described by rspbuf, rspdma, rsplen). If FCP_CONF is + * supported, the LLDD is to await FCP_CONF reception to confirm + * the RSP reception by the host. The LLDD may retramsit the + * FCP_RSP iu if FCP_CONF is not received per FC-NVME. Upon + * transmission of the FCP_RSP iu if FCP_CONF is not supported, + * or upon success/failure of FCP_CONF if it is supported, the + * LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and + * consider the operation complete. + * Upon completing the indicated operation, the LLDD is to set the + * status fields for the operation (tranferred_length and fcp_error + * status) in the request, then call the "done" routine + * indicated in the fcp request. After the operation completes, + * regardless of whether the FCP_RSP iu was successfully transmit, + * the LLDD-supplied exchange structure must remain valid until the + * transport calls the fcp_req_release() callback to return ownership + * of the exchange structure back to the LLDD so that it may be used + * for another fcp command. + * Note: when calling the done routine for READDATA or WRITEDATA + * operations, the fc-nvme layer may immediate convert, in the same + * thread and before returning to the LLDD, the fcp operation to + * the next operation for the fcp io and call the LLDDs fcp_op + * call again. If fields in the fcp request are to be accessed post + * the done call, the LLDD should save their values prior to calling + * the done routine, and inspect the save values after the done + * routine. + * Returns 0 on success, -<errno> on failure (Ex: -EIO) + * Entrypoint is Mandatory. + * + * @fcp_abort: Called by the transport to abort an active command. + * The command may be in-between operations (nothing active in LLDD) + * or may have an active WRITEDATA operation pending. The LLDD is to + * initiate the ABTS process for the command and return from the + * callback. The ABTS does not need to be complete on the command. + * The fcp_abort callback inherently cannot fail. After the + * fcp_abort() callback completes, the transport will wait for any + * outstanding operation (if there was one) to complete, then will + * call the fcp_req_release() callback to return the command's + * exchange context back to the LLDD. + * Entrypoint is Mandatory. + * + * @fcp_req_release: Called by the transport to return a nvmefc_tgt_fcp_req + * to the LLDD after all operations on the fcp operation are complete. + * This may be due to the command completing or upon completion of + * abort cleanup. + * Entrypoint is Mandatory. + * + * @defer_rcv: Called by the transport to signal the LLLD that it has + * begun processing of a previously received NVME CMD IU. The LLDD + * is now free to re-use the rcv buffer associated with the + * nvmefc_tgt_fcp_req. + * Entrypoint is Optional. + * + * @discovery_event: Called by the transport to generate an RSCN + * change notifications to NVME initiators. The RSCN notifications + * should cause the initiator to rescan the discovery controller + * on the targetport. + * + * @ls_req: Called to issue a FC-NVME FC-4 LS service request. + * The nvme_fc_ls_req structure will fully describe the buffers for + * the request payload and where to place the response payload. + * The targetport that is to issue the LS request is identified by + * the targetport argument. The remote port that is to receive the + * LS request is identified by the hosthandle argument. The nvmet-fc + * transport is only allowed to issue FC-NVME LS's on behalf of an + * association that was created prior by a Create Association LS. + * The hosthandle will originate from the LLDD in the struct + * nvmefc_ls_rsp structure for the Create Association LS that + * was delivered to the transport. The transport will save the + * hosthandle as an attribute of the association. If the LLDD + * loses connectivity with the remote port, it must call the + * nvmet_fc_invalidate_host() routine to remove any references to + * the remote port in the transport. + * The LLDD is to allocate an exchange, issue the LS request, obtain + * the LS response, and call the "done" routine specified in the + * request structure (argument to done is the ls request structure + * itself). + * Entrypoint is Optional - but highly recommended. + * + * @ls_abort: called to request the LLDD to abort the indicated ls request. + * The call may return before the abort has completed. After aborting + * the request, the LLDD must still call the ls request done routine + * indicating an FC transport Aborted status. + * Entrypoint is Mandatory if the ls_req entry point is specified. + * + * @host_release: called to inform the LLDD that the request to invalidate + * the host port indicated by the hosthandle has been fully completed. + * No associations exist with the host port and there will be no + * further references to hosthandle. + * Entrypoint is Mandatory if the lldd calls nvmet_fc_invalidate_host(). + * + * @max_hw_queues: indicates the maximum number of hw queues the LLDD + * supports for cpu affinitization. + * Value is Mandatory. Must be at least 1. + * + * @max_sgl_segments: indicates the maximum number of sgl segments supported + * by the LLDD + * Value is Mandatory. Must be at least 1. Recommend at least 256. + * + * @max_dif_sgl_segments: indicates the maximum number of sgl segments + * supported by the LLDD for DIF operations. + * Value is Mandatory. Must be at least 1. Recommend at least 256. + * + * @dma_boundary: indicates the dma address boundary where dma mappings + * will be split across. + * Value is Mandatory. Typical value is 0xFFFFFFFF to split across + * 4Gig address boundarys + * + * @target_features: The LLDD sets bits in this field to correspond to + * optional features that are supported by the LLDD. + * Refer to the NVMET_FCTGTFEAT_xxx values. + * Value is Mandatory. Allowed to be zero. + * + * @target_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like fc nvme layer to allocate on the LLDD's + * behalf whenever a targetport is allocated. The additional memory + * area solely for the of the LLDD and its location is specified by + * the targetport->private pointer. + * Value is Mandatory. Allowed to be zero. + * + * @lsrqst_priv_sz: The LLDD sets this field to the amount of additional + * memory that it would like nvmet-fc layer to allocate on the LLDD's + * behalf whenever a ls request structure is allocated. The additional + * memory area is solely for use by the LLDD and its location is + * specified by the ls_request->private pointer. + * Value is Mandatory. Allowed to be zero. + * + */ +struct nvmet_fc_target_template { + void (*targetport_delete)(struct nvmet_fc_target_port *tgtport); + int (*xmt_ls_rsp)(struct nvmet_fc_target_port *tgtport, + struct nvmefc_ls_rsp *ls_rsp); + int (*fcp_op)(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq); + void (*fcp_abort)(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq); + void (*fcp_req_release)(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq); + void (*defer_rcv)(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq); + void (*discovery_event)(struct nvmet_fc_target_port *tgtport); + int (*ls_req)(struct nvmet_fc_target_port *targetport, + void *hosthandle, struct nvmefc_ls_req *lsreq); + void (*ls_abort)(struct nvmet_fc_target_port *targetport, + void *hosthandle, struct nvmefc_ls_req *lsreq); + void (*host_release)(void *hosthandle); + + u32 max_hw_queues; + u16 max_sgl_segments; + u16 max_dif_sgl_segments; + u64 dma_boundary; + + u32 target_features; + + /* sizes of additional private data for data structures */ + u32 target_priv_sz; + u32 lsrqst_priv_sz; +}; + + +int nvmet_fc_register_targetport(struct nvmet_fc_port_info *portinfo, + struct nvmet_fc_target_template *template, + struct device *dev, + struct nvmet_fc_target_port **tgtport_p); + +int nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *tgtport); + +/* + * Routine called to pass a NVME-FC LS request, received by the lldd, + * to the nvmet-fc transport. + * + * If the return value is zero: the LS was successfully accepted by the + * transport. + * If the return value is non-zero: the transport has not accepted the + * LS. The lldd should ABTS-LS the LS. + * + * Note: if the LLDD receives and ABTS for the LS prior to the transport + * calling the ops->xmt_ls_rsp() routine to transmit a response, the LLDD + * shall mark the LS as aborted, and when the xmt_ls_rsp() is called: the + * response shall not be transmit and the struct nvmefc_ls_rsp() done + * routine shall be called. The LLDD may transmit the ABTS response as + * soon as the LS was marked or can delay until the xmt_ls_rsp() call is + * made. + * Note: if an RCV LS was successfully posted to the transport and the + * targetport is then unregistered before xmt_ls_rsp() was called for + * the lsrsp structure, the transport will still call xmt_ls_rsp() + * afterward to cleanup the outstanding lsrsp structure. The LLDD should + * noop the transmission of the rsp and call the lsrsp->done() routine + * to allow the lsrsp structure to be released. + */ +int nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *tgtport, + void *hosthandle, + struct nvmefc_ls_rsp *rsp, + void *lsreqbuf, u32 lsreqbuf_len); + +/* + * Routine called by the LLDD whenever it has a logout or loss of + * connectivity to a NVME-FC host port which there had been active + * NVMe controllers for. The host port is indicated by the + * hosthandle. The hosthandle is given to the nvmet-fc transport + * when a NVME LS was received, typically to create a new association. + * The nvmet-fc transport will cache the hostport value with the + * association for use in LS requests for the association. + * When the LLDD calls this routine, the nvmet-fc transport will + * immediately terminate all associations that were created with + * the hosthandle host port. + * The LLDD, after calling this routine and having control returned, + * must assume the transport may subsequently utilize hosthandle as + * part of sending LS's to terminate the association. The LLDD + * should reject the LS's if they are attempted. + * Once the last association has terminated for the hosthandle host + * port, the nvmet-fc transport will call the ops->host_release() + * callback. As of the callback, the nvmet-fc transport will no + * longer reference hosthandle. + */ +void nvmet_fc_invalidate_host(struct nvmet_fc_target_port *tgtport, + void *hosthandle); + +/* + * If nvmet_fc_rcv_fcp_req returns non-zero, the transport has not accepted + * the FCP cmd. The lldd should ABTS-LS the cmd. + */ +int nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq, + void *cmdiubuf, u32 cmdiubuf_len); + +void nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *tgtport, + struct nvmefc_tgt_fcp_req *fcpreq); + +#endif /* _NVME_FC_DRIVER_H */ |