include/linux/nvme-fc-driver.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (c) 2016, Avago Technologies
   4  */
   5
   6 #ifndef _NVME_FC_DRIVER_H
   7 #define _NVME_FC_DRIVER_H 1
   8
   9 #include <linux/scatterlist.h>
  10
  11
  12 /*
  13  * **********************  LLDD FC-NVME Host API ********************
  14  *
  15  *  For FC LLDD's that are the NVME Host role.
  16  *
  17  * ******************************************************************
  18  */
  19
  20
  21
  22 /**
  23  * struct nvme_fc_port_info - port-specific ids and FC connection-specific
  24  *                            data element used during NVME Host role
  25  *                            registrations
  26  *
  27  * Static fields describing the port being registered:
  28  * @node_name: FC WWNN for the port
  29  * @port_name: FC WWPN for the port
  30  * @port_role: What NVME roles are supported (see FC_PORT_ROLE_xxx)
  31  * @dev_loss_tmo: maximum delay for reconnects to an association on
  32  *             this device. Used only on a remoteport.
  33  *
  34  * Initialization values for dynamic port fields:
  35  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
  36  *                be set to 0.
  37  */
  38 struct nvme_fc_port_info {
  39         u64                     node_name;
  40         u64                     port_name;
  41         u32                     port_role;
  42         u32                     port_id;
  43         u32                     dev_loss_tmo;
  44 };
  45
  46
  47 /**
  48  * struct nvmefc_ls_req - Request structure passed from NVME-FC transport
  49  *                        to LLDD in order to perform a NVME FC-4 LS
  50  *                        request and obtain a response.
  51  *
  52  * Values set by the NVME-FC layer prior to calling the LLDD ls_req
  53  * entrypoint.
  54  * @rqstaddr: pointer to request buffer
  55  * @rqstdma:  PCI DMA address of request buffer
  56  * @rqstlen:  Length, in bytes, of request buffer
  57  * @rspaddr:  pointer to response buffer
  58  * @rspdma:   PCI DMA address of response buffer
  59  * @rsplen:   Length, in bytes, of response buffer
  60  * @timeout:  Maximum amount of time, in seconds, to wait for the LS response.
  61  *            If timeout exceeded, LLDD to abort LS exchange and complete
  62  *            LS request with error status.
  63  * @private:  pointer to memory allocated alongside the ls request structure
  64  *            that is specifically for the LLDD to use while processing the
  65  *            request. The length of the buffer corresponds to the
  66  *            lsrqst_priv_sz value specified in the nvme_fc_port_template
  67  *            supplied by the LLDD.
  68  * @done:     The callback routine the LLDD is to invoke upon completion of
  69  *            the LS request. req argument is the pointer to the original LS
  70  *            request structure. Status argument must be 0 upon success, a
  71  *            negative errno on failure (example: -ENXIO).
  72  */
  73 struct nvmefc_ls_req {
  74         void                    *rqstaddr;
  75         dma_addr_t              rqstdma;
  76         u32                     rqstlen;
  77         void                    *rspaddr;
  78         dma_addr_t              rspdma;
  79         u32                     rsplen;
  80         u32                     timeout;
  81
  82         void                    *private;
  83
  84         void (*done)(struct nvmefc_ls_req *req, int status);
  85
  86 } __aligned(sizeof(u64));       /* alignment for other things alloc'd with */
  87
  88
  89 enum nvmefc_fcp_datadir {
  90         NVMEFC_FCP_NODATA,      /* payload_length and sg_cnt will be zero */
  91         NVMEFC_FCP_WRITE,
  92         NVMEFC_FCP_READ,
  93 };
  94
  95
  96 /**
  97  * struct nvmefc_fcp_req - Request structure passed from NVME-FC transport
  98  *                         to LLDD in order to perform a NVME FCP IO operation.
  99  *
 100  * Values set by the NVME-FC layer prior to calling the LLDD fcp_io
 101  * entrypoint.
 102  * @cmdaddr:   pointer to the FCP CMD IU buffer
 103  * @rspaddr:   pointer to the FCP RSP IU buffer
 104  * @cmddma:    PCI DMA address of the FCP CMD IU buffer
 105  * @rspdma:    PCI DMA address of the FCP RSP IU buffer
 106  * @cmdlen:    Length, in bytes, of the FCP CMD IU buffer
 107  * @rsplen:    Length, in bytes, of the FCP RSP IU buffer
 108  * @payload_length: Length of DATA_IN or DATA_OUT payload data to transfer
 109  * @sg_table:  scatter/gather structure for payload data
 110  * @first_sgl: memory for 1st scatter/gather list segment for payload data
 111  * @sg_cnt:    number of elements in the scatter/gather list
 112  * @io_dir:    direction of the FCP request (see NVMEFC_FCP_xxx)
 113  * @sqid:      The nvme SQID the command is being issued on
 114  * @done:      The callback routine the LLDD is to invoke upon completion of
 115  *             the FCP operation. req argument is the pointer to the original
 116  *             FCP IO operation.
 117  * @private:   pointer to memory allocated alongside the FCP operation
 118  *             request structure that is specifically for the LLDD to use
 119  *             while processing the operation. The length of the buffer
 120  *             corresponds to the fcprqst_priv_sz value specified in the
 121  *             nvme_fc_port_template supplied by the LLDD.
 122  *
 123  * Values set by the LLDD indicating completion status of the FCP operation.
 124  * Must be set prior to calling the done() callback.
 125  * @transferred_length: amount of payload data, in bytes, that were
 126  *             transferred. Should equal payload_length on success.
 127  * @rcv_rsplen: length, in bytes, of the FCP RSP IU received.
 128  * @status:    Completion status of the FCP operation. must be 0 upon success,
 129  *             negative errno value upon failure (ex: -EIO). Note: this is
 130  *             NOT a reflection of the NVME CQE completion status. Only the
 131  *             status of the FCP operation at the NVME-FC level.
 132  */
 133 struct nvmefc_fcp_req {
 134         void                    *cmdaddr;
 135         void                    *rspaddr;
 136         dma_addr_t              cmddma;
 137         dma_addr_t              rspdma;
 138         u16                     cmdlen;
 139         u16                     rsplen;
 140
 141         u32                     payload_length;
 142         struct sg_table         sg_table;
 143         struct scatterlist      *first_sgl;
 144         int                     sg_cnt;
 145         enum nvmefc_fcp_datadir io_dir;
 146
 147         __le16                  sqid;
 148
 149         void (*done)(struct nvmefc_fcp_req *req);
 150
 151         void                    *private;
 152
 153         u32                     transferred_length;
 154         u16                     rcv_rsplen;
 155         u32                     status;
 156 } __aligned(sizeof(u64));       /* alignment for other things alloc'd with */
 157
 158
 159 /*
 160  * Direct copy of fc_port_state enum. For later merging
 161  */
 162 enum nvme_fc_obj_state {
 163         FC_OBJSTATE_UNKNOWN,
 164         FC_OBJSTATE_NOTPRESENT,
 165         FC_OBJSTATE_ONLINE,
 166         FC_OBJSTATE_OFFLINE,            /* User has taken Port Offline */
 167         FC_OBJSTATE_BLOCKED,
 168         FC_OBJSTATE_BYPASSED,
 169         FC_OBJSTATE_DIAGNOSTICS,
 170         FC_OBJSTATE_LINKDOWN,
 171         FC_OBJSTATE_ERROR,
 172         FC_OBJSTATE_LOOPBACK,
 173         FC_OBJSTATE_DELETED,
 174 };
 175
 176
 177 /**
 178  * struct nvme_fc_local_port - structure used between NVME-FC transport and
 179  *                 a LLDD to reference a local NVME host port.
 180  *                 Allocated/created by the nvme_fc_register_localport()
 181  *                 transport interface.
 182  *
 183  * Fields with static values for the port. Initialized by the
 184  * port_info struct supplied to the registration call.
 185  * @port_num:  NVME-FC transport host port number
 186  * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx)
 187  * @node_name: FC WWNN for the port
 188  * @port_name: FC WWPN for the port
 189  * @private:   pointer to memory allocated alongside the local port
 190  *             structure that is specifically for the LLDD to use.
 191  *             The length of the buffer corresponds to the local_priv_sz
 192  *             value specified in the nvme_fc_port_template supplied by
 193  *             the LLDD.
 194  * @dev_loss_tmo: maximum delay for reconnects to an association on
 195  *             this device. To modify, lldd must call
 196  *             nvme_fc_set_remoteport_devloss().
 197  *
 198  * Fields with dynamic values. Values may change base on link state. LLDD
 199  * may reference fields directly to change them. Initialized by the
 200  * port_info struct supplied to the registration call.
 201  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
 202  *                be set to 0.
 203  * @port_state:   Operational state of the port.
 204  */
 205 struct nvme_fc_local_port {
 206         /* static/read-only fields */
 207         u32 port_num;
 208         u32 port_role;
 209         u64 node_name;
 210         u64 port_name;
 211
 212         void *private;
 213
 214         /* dynamic fields */
 215         u32 port_id;
 216         enum nvme_fc_obj_state port_state;
 217 } __aligned(sizeof(u64));       /* alignment for other things alloc'd with */
 218
 219
 220 /**
 221  * struct nvme_fc_remote_port - structure used between NVME-FC transport and
 222  *                 a LLDD to reference a remote NVME subsystem port.
 223  *                 Allocated/created by the nvme_fc_register_remoteport()
 224  *                 transport interface.
 225  *
 226  * Fields with static values for the port. Initialized by the
 227  * port_info struct supplied to the registration call.
 228  * @port_num:  NVME-FC transport remote subsystem port number
 229  * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx)
 230  * @node_name: FC WWNN for the port
 231  * @port_name: FC WWPN for the port
 232  * @localport: pointer to the NVME-FC local host port the subsystem is
 233  *             connected to.
 234  * @private:   pointer to memory allocated alongside the remote port
 235  *             structure that is specifically for the LLDD to use.
 236  *             The length of the buffer corresponds to the remote_priv_sz
 237  *             value specified in the nvme_fc_port_template supplied by
 238  *             the LLDD.
 239  *
 240  * Fields with dynamic values. Values may change base on link or login
 241  * state. LLDD may reference fields directly to change them. Initialized by
 242  * the port_info struct supplied to the registration call.
 243  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
 244  *                be set to 0.
 245  * @port_state:   Operational state of the remote port. Valid values are
 246  *                ONLINE or UNKNOWN.
 247  */
 248 struct nvme_fc_remote_port {
 249         /* static fields */
 250         u32 port_num;
 251         u32 port_role;
 252         u64 node_name;
 253         u64 port_name;
 254         struct nvme_fc_local_port *localport;
 255         void *private;
 256         u32 dev_loss_tmo;
 257
 258         /* dynamic fields */
 259         u32 port_id;
 260         enum nvme_fc_obj_state port_state;
 261 } __aligned(sizeof(u64));       /* alignment for other things alloc'd with */
 262
 263
 264 /**
 265  * struct nvme_fc_port_template - structure containing static entrypoints and
 266  *                 operational parameters for an LLDD that supports NVME host
 267  *                 behavior. Passed by reference in port registrations.
 268  *                 NVME-FC transport remembers template reference and may
 269  *                 access it during runtime operation.
 270  *
 271  * Host/Initiator Transport Entrypoints/Parameters:
 272  *
 273  * @localport_delete:  The LLDD initiates deletion of a localport via
 274  *       nvme_fc_deregister_localport(). However, the teardown is
 275  *       asynchronous. This routine is called upon the completion of the
 276  *       teardown to inform the LLDD that the localport has been deleted.
 277  *       Entrypoint is Mandatory.
 278  *
 279  * @remoteport_delete:  The LLDD initiates deletion of a remoteport via
 280  *       nvme_fc_deregister_remoteport(). However, the teardown is
 281  *       asynchronous. This routine is called upon the completion of the
 282  *       teardown to inform the LLDD that the remoteport has been deleted.
 283  *       Entrypoint is Mandatory.
 284  *
 285  * @create_queue:  Upon creating a host<->controller association, queues are
 286  *       created such that they can be affinitized to cpus/cores. This
 287  *       callback into the LLDD to notify that a controller queue is being
 288  *       created.  The LLDD may choose to allocate an associated hw queue
 289  *       or map it onto a shared hw queue. Upon return from the call, the
 290  *       LLDD specifies a handle that will be given back to it for any
 291  *       command that is posted to the controller queue.  The handle can
 292  *       be used by the LLDD to map quickly to the proper hw queue for
 293  *       command execution.  The mask of cpu's that will map to this queue
 294  *       at the block-level is also passed in. The LLDD should use the
 295  *       queue id and/or cpu masks to ensure proper affinitization of the
 296  *       controller queue to the hw queue.
 297  *       Entrypoint is Optional.
 298  *
 299  * @delete_queue:  This is the inverse of the crete_queue. During
 300  *       host<->controller association teardown, this routine is called
 301  *       when a controller queue is being terminated. Any association with
 302  *       a hw queue should be termined. If there is a unique hw queue, the
 303  *       hw queue should be torn down.
 304  *       Entrypoint is Optional.
 305  *
 306  * @poll_queue:  Called to poll for the completion of an io on a blk queue.
 307  *       Entrypoint is Optional.
 308  *
 309  * @ls_req:  Called to issue a FC-NVME FC-4 LS service request.
 310  *       The nvme_fc_ls_req structure will fully describe the buffers for
 311  *       the request payload and where to place the response payload. The
 312  *       LLDD is to allocate an exchange, issue the LS request, obtain the
 313  *       LS response, and call the "done" routine specified in the request
 314  *       structure (argument to done is the ls request structure itself).
 315  *       Entrypoint is Mandatory.
 316  *
 317  * @fcp_io:  called to issue a FC-NVME I/O request.  The I/O may be for
 318  *       an admin queue or an i/o queue.  The nvmefc_fcp_req structure will
 319  *       fully describe the io: the buffer containing the FC-NVME CMD IU
 320  *       (which contains the SQE), the sg list for the payload if applicable,
 321  *       and the buffer to place the FC-NVME RSP IU into.  The LLDD will
 322  *       complete the i/o, indicating the amount of data transferred or
 323  *       any transport error, and call the "done" routine specified in the
 324  *       request structure (argument to done is the fcp request structure
 325  *       itself).
 326  *       Entrypoint is Mandatory.
 327  *
 328  * @ls_abort: called to request the LLDD to abort the indicated ls request.
 329  *       The call may return before the abort has completed. After aborting
 330  *       the request, the LLDD must still call the ls request done routine
 331  *       indicating an FC transport Aborted status.
 332  *       Entrypoint is Mandatory.
 333  *
 334  * @fcp_abort: called to request the LLDD to abort the indicated fcp request.
 335  *       The call may return before the abort has completed. After aborting
 336  *       the request, the LLDD must still call the fcp request done routine
 337  *       indicating an FC transport Aborted status.
 338  *       Entrypoint is Mandatory.
 339  *
 340  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
 341  *       supports for cpu affinitization.
 342  *       Value is Mandatory. Must be at least 1.
 343  *
 344  * @max_sgl_segments:  indicates the maximum number of sgl segments supported
 345  *       by the LLDD
 346  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
 347  *
 348  * @max_dif_sgl_segments:  indicates the maximum number of sgl segments
 349  *       supported by the LLDD for DIF operations.
 350  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
 351  *
 352  * @dma_boundary:  indicates the dma address boundary where dma mappings
 353  *       will be split across.
 354  *       Value is Mandatory. Typical value is 0xFFFFFFFF to split across
 355  *       4Gig address boundarys
 356  *
 357  * @local_priv_sz: The LLDD sets this field to the amount of additional
 358  *       memory that it would like fc nvme layer to allocate on the LLDD's
 359  *       behalf whenever a localport is allocated.  The additional memory
 360  *       area solely for the of the LLDD and its location is specified by
 361  *       the localport->private pointer.
 362  *       Value is Mandatory. Allowed to be zero.
 363  *
 364  * @remote_priv_sz: The LLDD sets this field to the amount of additional
 365  *       memory that it would like fc nvme layer to allocate on the LLDD's
 366  *       behalf whenever a remoteport is allocated.  The additional memory
 367  *       area solely for the of the LLDD and its location is specified by
 368  *       the remoteport->private pointer.
 369  *       Value is Mandatory. Allowed to be zero.
 370  *
 371  * @lsrqst_priv_sz: The LLDD sets this field to the amount of additional
 372  *       memory that it would like fc nvme layer to allocate on the LLDD's
 373  *       behalf whenever a ls request structure is allocated. The additional
 374  *       memory area solely for the of the LLDD and its location is
 375  *       specified by the ls_request->private pointer.
 376  *       Value is Mandatory. Allowed to be zero.
 377  *
 378  * @fcprqst_priv_sz: The LLDD sets this field to the amount of additional
 379  *       memory that it would like fc nvme layer to allocate on the LLDD's
 380  *       behalf whenever a fcp request structure is allocated. The additional
 381  *       memory area solely for the of the LLDD and its location is
 382  *       specified by the fcp_request->private pointer.
 383  *       Value is Mandatory. Allowed to be zero.
 384  */
 385 struct nvme_fc_port_template {
 386         /* initiator-based functions */
 387         void    (*localport_delete)(struct nvme_fc_local_port *);
 388         void    (*remoteport_delete)(struct nvme_fc_remote_port *);
 389         int     (*create_queue)(struct nvme_fc_local_port *,
 390                                 unsigned int qidx, u16 qsize,
 391                                 void **handle);
 392         void    (*delete_queue)(struct nvme_fc_local_port *,
 393                                 unsigned int qidx, void *handle);
 394         int     (*ls_req)(struct nvme_fc_local_port *,
 395                                 struct nvme_fc_remote_port *,
 396                                 struct nvmefc_ls_req *);
 397         int     (*fcp_io)(struct nvme_fc_local_port *,
 398                                 struct nvme_fc_remote_port *,
 399                                 void *hw_queue_handle,
 400                                 struct nvmefc_fcp_req *);
 401         void    (*ls_abort)(struct nvme_fc_local_port *,
 402                                 struct nvme_fc_remote_port *,
 403                                 struct nvmefc_ls_req *);
 404         void    (*fcp_abort)(struct nvme_fc_local_port *,
 405                                 struct nvme_fc_remote_port *,
 406                                 void *hw_queue_handle,
 407                                 struct nvmefc_fcp_req *);
 408
 409         u32     max_hw_queues;
 410         u16     max_sgl_segments;
 411         u16     max_dif_sgl_segments;
 412         u64     dma_boundary;
 413
 414         /* sizes of additional private data for data structures */
 415         u32     local_priv_sz;
 416         u32     remote_priv_sz;
 417         u32     lsrqst_priv_sz;
 418         u32     fcprqst_priv_sz;
 419 };
 420
 421
 422 /*
 423  * Initiator/Host functions
 424  */
 425
 426 int nvme_fc_register_localport(struct nvme_fc_port_info *pinfo,
 427                         struct nvme_fc_port_template *template,
 428                         struct device *dev,
 429                         struct nvme_fc_local_port **lport_p);
 430
 431 int nvme_fc_unregister_localport(struct nvme_fc_local_port *localport);
 432
 433 int nvme_fc_register_remoteport(struct nvme_fc_local_port *localport,
 434                         struct nvme_fc_port_info *pinfo,
 435                         struct nvme_fc_remote_port **rport_p);
 436
 437 int nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *remoteport);
 438
 439 void nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport);
 440
 441 int nvme_fc_set_remoteport_devloss(struct nvme_fc_remote_port *remoteport,
 442                         u32 dev_loss_tmo);
 443
 444
 445 /*
 446  * ***************  LLDD FC-NVME Target/Subsystem API ***************
 447  *
 448  *  For FC LLDD's that are the NVME Subsystem role
 449  *
 450  * ******************************************************************
 451  */
 452
 453 /**
 454  * struct nvmet_fc_port_info - port-specific ids and FC connection-specific
 455  *                             data element used during NVME Subsystem role
 456  *                             registrations
 457  *
 458  * Static fields describing the port being registered:
 459  * @node_name: FC WWNN for the port
 460  * @port_name: FC WWPN for the port
 461  *
 462  * Initialization values for dynamic port fields:
 463  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
 464  *                be set to 0.
 465  */
 466 struct nvmet_fc_port_info {
 467         u64                     node_name;
 468         u64                     port_name;
 469         u32                     port_id;
 470 };
 471
 472
 473 /**
 474  * struct nvmefc_tgt_ls_req - Structure used between LLDD and NVMET-FC
 475  *                            layer to represent the exchange context for
 476  *                            a FC-NVME Link Service (LS).
 477  *
 478  * The structure is allocated by the LLDD whenever a LS Request is received
 479  * from the FC link. The address of the structure is passed to the nvmet-fc
 480  * layer via the nvmet_fc_rcv_ls_req() call. The address of the structure
 481  * will be passed back to the LLDD when the response is to be transmit.
 482  * The LLDD is to use the address to map back to the LLDD exchange structure
 483  * which maintains information such as the targetport the LS was received
 484  * on, the remote FC NVME initiator that sent the LS, and any FC exchange
 485  * context.  Upon completion of the LS response transmit, the address of the
 486  * structure will be passed back to the LS rsp done() routine, allowing the
 487  * nvmet-fc layer to release dma resources. Upon completion of the done()
 488  * routine, no further access will be made by the nvmet-fc layer and the
 489  * LLDD can de-allocate the structure.
 490  *
 491  * Field initialization:
 492  *   At the time of the nvmet_fc_rcv_ls_req() call, there is no content that
 493  *     is valid in the structure.
 494  *
 495  *   When the structure is used for the LLDD->xmt_ls_rsp() call, the nvmet-fc
 496  *     layer will fully set the fields in order to specify the response
 497  *     payload buffer and its length as well as the done routine to be called
 498  *     upon compeletion of the transmit.  The nvmet-fc layer will also set a
 499  *     private pointer for its own use in the done routine.
 500  *
 501  * Values set by the NVMET-FC layer prior to calling the LLDD xmt_ls_rsp
 502  * entrypoint.
 503  * @rspbuf:   pointer to the LS response buffer
 504  * @rspdma:   PCI DMA address of the LS response buffer
 505  * @rsplen:   Length, in bytes, of the LS response buffer
 506  * @done:     The callback routine the LLDD is to invoke upon completion of
 507  *            transmitting the LS response. req argument is the pointer to
 508  *            the original ls request.
 509  * @nvmet_fc_private:  pointer to an internal NVMET-FC layer structure used
 510  *            as part of the NVMET-FC processing. The LLDD is not to access
 511  *            this pointer.
 512  */
 513 struct nvmefc_tgt_ls_req {
 514         void            *rspbuf;
 515         dma_addr_t      rspdma;
 516         u16             rsplen;
 517
 518         void (*done)(struct nvmefc_tgt_ls_req *req);
 519         void *nvmet_fc_private;         /* LLDD is not to access !! */
 520 };
 521
 522 /* Operations that NVME-FC layer may request the LLDD to perform for FCP */
 523 enum {
 524         NVMET_FCOP_READDATA     = 1,    /* xmt data to initiator */
 525         NVMET_FCOP_WRITEDATA    = 2,    /* xmt data from initiator */
 526         NVMET_FCOP_READDATA_RSP = 3,    /* xmt data to initiator and send
 527                                          * rsp as well
 528                                          */
 529         NVMET_FCOP_RSP          = 4,    /* send rsp frame */
 530 };
 531
 532 /**
 533  * struct nvmefc_tgt_fcp_req - Structure used between LLDD and NVMET-FC
 534  *                            layer to represent the exchange context and
 535  *                            the specific FC-NVME IU operation(s) to perform
 536  *                            for a FC-NVME FCP IO.
 537  *
 538  * Structure used between LLDD and nvmet-fc layer to represent the exchange
 539  * context for a FC-NVME FCP I/O operation (e.g. a nvme sqe, the sqe-related
 540  * memory transfers, and its assocated cqe transfer).
 541  *
 542  * The structure is allocated by the LLDD whenever a FCP CMD IU is received
 543  * from the FC link. The address of the structure is passed to the nvmet-fc
 544  * layer via the nvmet_fc_rcv_fcp_req() call. The address of the structure
 545  * will be passed back to the LLDD for the data operations and transmit of
 546  * the response. The LLDD is to use the address to map back to the LLDD
 547  * exchange structure which maintains information such as the targetport
 548  * the FCP I/O was received on, the remote FC NVME initiator that sent the
 549  * FCP I/O, and any FC exchange context.  Upon completion of the FCP target
 550  * operation, the address of the structure will be passed back to the FCP
 551  * op done() routine, allowing the nvmet-fc layer to release dma resources.
 552  * Upon completion of the done() routine for either RSP or ABORT ops, no
 553  * further access will be made by the nvmet-fc layer and the LLDD can
 554  * de-allocate the structure.
 555  *
 556  * Field initialization:
 557  *   At the time of the nvmet_fc_rcv_fcp_req() call, there is no content that
 558  *     is valid in the structure.
 559  *
 560  *   When the structure is used for an FCP target operation, the nvmet-fc
 561  *     layer will fully set the fields in order to specify the scattergather
 562  *     list, the transfer length, as well as the done routine to be called
 563  *     upon compeletion of the operation.  The nvmet-fc layer will also set a
 564  *     private pointer for its own use in the done routine.
 565  *
 566  * Values set by the NVMET-FC layer prior to calling the LLDD fcp_op
 567  * entrypoint.
 568  * @op:       Indicates the FCP IU operation to perform (see NVMET_FCOP_xxx)
 569  * @hwqid:    Specifies the hw queue index (0..N-1, where N is the
 570  *            max_hw_queues value from the LLD's nvmet_fc_target_template)
 571  *            that the operation is to use.
 572  * @offset:   Indicates the DATA_OUT/DATA_IN payload offset to be tranferred.
 573  *            Field is only valid on WRITEDATA, READDATA, or READDATA_RSP ops.
 574  * @timeout:  amount of time, in seconds, to wait for a response from the NVME
 575  *            host. A value of 0 is an infinite wait.
 576  *            Valid only for the following ops:
 577  *              WRITEDATA: caps the wait for data reception
 578  *              READDATA_RSP & RSP: caps wait for FCP_CONF reception (if used)
 579  * @transfer_length: the length, in bytes, of the DATA_OUT or DATA_IN payload
 580  *            that is to be transferred.
 581  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
 582  * @ba_rjt:   Contains the BA_RJT payload that is to be transferred.
 583  *            Valid only for the NVMET_FCOP_BA_RJT op.
 584  * @sg:       Scatter/gather list for the DATA_OUT/DATA_IN payload data.
 585  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
 586  * @sg_cnt:   Number of valid entries in the scatter/gather list.
 587  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
 588  * @rspaddr:  pointer to the FCP RSP IU buffer to be transmit
 589  *            Used by RSP and READDATA_RSP ops
 590  * @rspdma:   PCI DMA address of the FCP RSP IU buffer
 591  *            Used by RSP and READDATA_RSP ops
 592  * @rsplen:   Length, in bytes, of the FCP RSP IU buffer
 593  *            Used by RSP and READDATA_RSP ops
 594  * @done:     The callback routine the LLDD is to invoke upon completion of
 595  *            the operation. req argument is the pointer to the original
 596  *            FCP subsystem op request.
 597  * @nvmet_fc_private:  pointer to an internal NVMET-FC layer structure used
 598  *            as part of the NVMET-FC processing. The LLDD is not to
 599  *            reference this field.
 600  *
 601  * Values set by the LLDD indicating completion status of the FCP operation.
 602  * Must be set prior to calling the done() callback.
 603  * @transferred_length: amount of DATA_OUT payload data received by a
 604  *            a WRITEDATA operation. If not a WRITEDATA operation, value must
 605  *            be set to 0. Should equal transfer_length on success.
 606  * @fcp_error: status of the FCP operation. Must be 0 on success; on failure
 607  *            must be a NVME_SC_FC_xxxx value.
 608  */
 609 struct nvmefc_tgt_fcp_req {
 610         u8                      op;
 611         u16                     hwqid;
 612         u32                     offset;
 613         u32                     timeout;
 614         u32                     transfer_length;
 615         struct fc_ba_rjt        ba_rjt;
 616         struct scatterlist      *sg;
 617         int                     sg_cnt;
 618         void                    *rspaddr;
 619         dma_addr_t              rspdma;
 620         u16                     rsplen;
 621
 622         void (*done)(struct nvmefc_tgt_fcp_req *);
 623
 624         void *nvmet_fc_private;         /* LLDD is not to access !! */
 625
 626         u32                     transferred_length;
 627         int                     fcp_error;
 628 };
 629
 630
 631 /* Target Features (Bit fields) LLDD supports */
 632 enum {
 633         NVMET_FCTGTFEAT_READDATA_RSP = (1 << 0),
 634                 /* Bit 0: supports the NVMET_FCPOP_READDATA_RSP op, which
 635                  * sends (the last) Read Data sequence followed by the RSP
 636                  * sequence in one LLDD operation. Errors during Data
 637                  * sequence transmit must not allow RSP sequence to be sent.
 638                  */
 639 };
 640
 641
 642 /**
 643  * struct nvmet_fc_target_port - structure used between NVME-FC transport and
 644  *                 a LLDD to reference a local NVME subsystem port.
 645  *                 Allocated/created by the nvme_fc_register_targetport()
 646  *                 transport interface.
 647  *
 648  * Fields with static values for the port. Initialized by the
 649  * port_info struct supplied to the registration call.
 650  * @port_num:  NVME-FC transport subsytem port number
 651  * @node_name: FC WWNN for the port
 652  * @port_name: FC WWPN for the port
 653  * @private:   pointer to memory allocated alongside the local port
 654  *             structure that is specifically for the LLDD to use.
 655  *             The length of the buffer corresponds to the target_priv_sz
 656  *             value specified in the nvme_fc_target_template supplied by
 657  *             the LLDD.
 658  *
 659  * Fields with dynamic values. Values may change base on link state. LLDD
 660  * may reference fields directly to change them. Initialized by the
 661  * port_info struct supplied to the registration call.
 662  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
 663  *                be set to 0.
 664  * @port_state:   Operational state of the port.
 665  */
 666 struct nvmet_fc_target_port {
 667         /* static/read-only fields */
 668         u32 port_num;
 669         u64 node_name;
 670         u64 port_name;
 671
 672         void *private;
 673
 674         /* dynamic fields */
 675         u32 port_id;
 676         enum nvme_fc_obj_state port_state;
 677 } __aligned(sizeof(u64));       /* alignment for other things alloc'd with */
 678
 679
 680 /**
 681  * struct nvmet_fc_target_template - structure containing static entrypoints
 682  *                 and operational parameters for an LLDD that supports NVME
 683  *                 subsystem behavior. Passed by reference in port
 684  *                 registrations. NVME-FC transport remembers template
 685  *                 reference and may access it during runtime operation.
 686  *
 687  * Subsystem/Target Transport Entrypoints/Parameters:
 688  *
 689  * @targetport_delete:  The LLDD initiates deletion of a targetport via
 690  *       nvmet_fc_unregister_targetport(). However, the teardown is
 691  *       asynchronous. This routine is called upon the completion of the
 692  *       teardown to inform the LLDD that the targetport has been deleted.
 693  *       Entrypoint is Mandatory.
 694  *
 695  * @xmt_ls_rsp:  Called to transmit the response to a FC-NVME FC-4 LS service.
 696  *       The nvmefc_tgt_ls_req structure is the same LLDD-supplied exchange
 697  *       structure specified in the nvmet_fc_rcv_ls_req() call made when
 698  *       the LS request was received.  The structure will fully describe
 699  *       the buffers for the response payload and the dma address of the
 700  *       payload. The LLDD is to transmit the response (or return a non-zero
 701  *       errno status), and upon completion of the transmit, call the
 702  *       "done" routine specified in the nvmefc_tgt_ls_req structure
 703  *       (argument to done is the ls reqwuest structure itself).
 704  *       After calling the done routine, the LLDD shall consider the
 705  *       LS handling complete and the nvmefc_tgt_ls_req structure may
 706  *       be freed/released.
 707  *       Entrypoint is Mandatory.
 708  *
 709  * @fcp_op:  Called to perform a data transfer or transmit a response.
 710  *       The nvmefc_tgt_fcp_req structure is the same LLDD-supplied
 711  *       exchange structure specified in the nvmet_fc_rcv_fcp_req() call
 712  *       made when the FCP CMD IU was received. The op field in the
 713  *       structure shall indicate the operation for the LLDD to perform
 714  *       relative to the io.
 715  *         NVMET_FCOP_READDATA operation: the LLDD is to send the
 716  *           payload data (described by sglist) to the host in 1 or
 717  *           more FC sequences (preferrably 1).  Note: the fc-nvme layer
 718  *           may call the READDATA operation multiple times for longer
 719  *           payloads.
 720  *         NVMET_FCOP_WRITEDATA operation: the LLDD is to receive the
 721  *           payload data (described by sglist) from the host via 1 or
 722  *           more FC sequences (preferrably 1). The LLDD is to generate
 723  *           the XFER_RDY IU(s) corresponding to the data being requested.
 724  *           Note: the FC-NVME layer may call the WRITEDATA operation
 725  *           multiple times for longer payloads.
 726  *         NVMET_FCOP_READDATA_RSP operation: the LLDD is to send the
 727  *           payload data (described by sglist) to the host in 1 or
 728  *           more FC sequences (preferrably 1). If an error occurs during
 729  *           payload data transmission, the LLDD is to set the
 730  *           nvmefc_tgt_fcp_req fcp_error and transferred_length field, then
 731  *           consider the operation complete. On error, the LLDD is to not
 732  *           transmit the FCP_RSP iu. If all payload data is transferred
 733  *           successfully, the LLDD is to update the nvmefc_tgt_fcp_req
 734  *           transferred_length field and may subsequently transmit the
 735  *           FCP_RSP iu payload (described by rspbuf, rspdma, rsplen).
 736  *           If FCP_CONF is supported, the LLDD is to await FCP_CONF
 737  *           reception to confirm the RSP reception by the host. The LLDD
 738  *           may retramsit the FCP_RSP iu if necessary per FC-NVME. Upon
 739  *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
 740  *           or upon success/failure of FCP_CONF if it is supported, the
 741  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
 742  *           consider the operation complete.
 743  *         NVMET_FCOP_RSP: the LLDD is to transmit the FCP_RSP iu payload
 744  *           (described by rspbuf, rspdma, rsplen). If FCP_CONF is
 745  *           supported, the LLDD is to await FCP_CONF reception to confirm
 746  *           the RSP reception by the host. The LLDD may retramsit the
 747  *           FCP_RSP iu if FCP_CONF is not received per FC-NVME. Upon
 748  *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
 749  *           or upon success/failure of FCP_CONF if it is supported, the
 750  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
 751  *           consider the operation complete.
 752  *       Upon completing the indicated operation, the LLDD is to set the
 753  *       status fields for the operation (tranferred_length and fcp_error
 754  *       status) in the request, then call the "done" routine
 755  *       indicated in the fcp request. After the operation completes,
 756  *       regardless of whether the FCP_RSP iu was successfully transmit,
 757  *       the LLDD-supplied exchange structure must remain valid until the
 758  *       transport calls the fcp_req_release() callback to return ownership
 759  *       of the exchange structure back to the LLDD so that it may be used
 760  *       for another fcp command.
 761  *       Note: when calling the done routine for READDATA or WRITEDATA
 762  *       operations, the fc-nvme layer may immediate convert, in the same
 763  *       thread and before returning to the LLDD, the fcp operation to
 764  *       the next operation for the fcp io and call the LLDDs fcp_op
 765  *       call again. If fields in the fcp request are to be accessed post
 766  *       the done call, the LLDD should save their values prior to calling
 767  *       the done routine, and inspect the save values after the done
 768  *       routine.
 769  *       Returns 0 on success, -<errno> on failure (Ex: -EIO)
 770  *       Entrypoint is Mandatory.
 771  *
 772  * @fcp_abort:  Called by the transport to abort an active command.
 773  *       The command may be in-between operations (nothing active in LLDD)
 774  *       or may have an active WRITEDATA operation pending. The LLDD is to
 775  *       initiate the ABTS process for the command and return from the
 776  *       callback. The ABTS does not need to be complete on the command.
 777  *       The fcp_abort callback inherently cannot fail. After the
 778  *       fcp_abort() callback completes, the transport will wait for any
 779  *       outstanding operation (if there was one) to complete, then will
 780  *       call the fcp_req_release() callback to return the command's
 781  *       exchange context back to the LLDD.
 782  *       Entrypoint is Mandatory.
 783  *
 784  * @fcp_req_release:  Called by the transport to return a nvmefc_tgt_fcp_req
 785  *       to the LLDD after all operations on the fcp operation are complete.
 786  *       This may be due to the command completing or upon completion of
 787  *       abort cleanup.
 788  *       Entrypoint is Mandatory.
 789  *
 790  * @defer_rcv:  Called by the transport to signal the LLLD that it has
 791  *       begun processing of a previously received NVME CMD IU. The LLDD
 792  *       is now free to re-use the rcv buffer associated with the
 793  *       nvmefc_tgt_fcp_req.
 794  *       Entrypoint is Optional.
 795  *
 796  * @discovery_event:  Called by the transport to generate an RSCN
 797  *       change notifications to NVME initiators. The RSCN notifications
 798  *       should cause the initiator to rescan the discovery controller
 799  *       on the targetport.
 800  *
 801  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
 802  *       supports for cpu affinitization.
 803  *       Value is Mandatory. Must be at least 1.
 804  *
 805  * @max_sgl_segments:  indicates the maximum number of sgl segments supported
 806  *       by the LLDD
 807  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
 808  *
 809  * @max_dif_sgl_segments:  indicates the maximum number of sgl segments
 810  *       supported by the LLDD for DIF operations.
 811  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
 812  *
 813  * @dma_boundary:  indicates the dma address boundary where dma mappings
 814  *       will be split across.
 815  *       Value is Mandatory. Typical value is 0xFFFFFFFF to split across
 816  *       4Gig address boundarys
 817  *
 818  * @target_features: The LLDD sets bits in this field to correspond to
 819  *       optional features that are supported by the LLDD.
 820  *       Refer to the NVMET_FCTGTFEAT_xxx values.
 821  *       Value is Mandatory. Allowed to be zero.
 822  *
 823  * @target_priv_sz: The LLDD sets this field to the amount of additional
 824  *       memory that it would like fc nvme layer to allocate on the LLDD's
 825  *       behalf whenever a targetport is allocated.  The additional memory
 826  *       area solely for the of the LLDD and its location is specified by
 827  *       the targetport->private pointer.
 828  *       Value is Mandatory. Allowed to be zero.
 829  */
 830 struct nvmet_fc_target_template {
 831         void (*targetport_delete)(struct nvmet_fc_target_port *tgtport);
 832         int (*xmt_ls_rsp)(struct nvmet_fc_target_port *tgtport,
 833                                 struct nvmefc_tgt_ls_req *tls_req);
 834         int (*fcp_op)(struct nvmet_fc_target_port *tgtport,
 835                                 struct nvmefc_tgt_fcp_req *fcpreq);
 836         void (*fcp_abort)(struct nvmet_fc_target_port *tgtport,
 837                                 struct nvmefc_tgt_fcp_req *fcpreq);
 838         void (*fcp_req_release)(struct nvmet_fc_target_port *tgtport,
 839                                 struct nvmefc_tgt_fcp_req *fcpreq);
 840         void (*defer_rcv)(struct nvmet_fc_target_port *tgtport,
 841                                 struct nvmefc_tgt_fcp_req *fcpreq);
 842         void (*discovery_event)(struct nvmet_fc_target_port *tgtport);
 843
 844         u32     max_hw_queues;
 845         u16     max_sgl_segments;
 846         u16     max_dif_sgl_segments;
 847         u64     dma_boundary;
 848
 849         u32     target_features;
 850
 851         u32     target_priv_sz;
 852 };
 853
 854
 855 int nvmet_fc_register_targetport(struct nvmet_fc_port_info *portinfo,
 856                         struct nvmet_fc_target_template *template,
 857                         struct device *dev,
 858                         struct nvmet_fc_target_port **tgtport_p);
 859
 860 int nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *tgtport);
 861
 862 int nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *tgtport,
 863                         struct nvmefc_tgt_ls_req *lsreq,
 864                         void *lsreqbuf, u32 lsreqbuf_len);
 865
 866 int nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *tgtport,
 867                         struct nvmefc_tgt_fcp_req *fcpreq,
 868                         void *cmdiubuf, u32 cmdiubuf_len);
 869
 870 void nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *tgtport,
 871                         struct nvmefc_tgt_fcp_req *fcpreq);
 872
 873 #endif /* _NVME_FC_DRIVER_H */