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 #include <linux/blk-mq.h>
11 
12 
13 /*
14  * **********************  FC-NVME LS API ********************
15  *
16  *  Data structures used by both FC-NVME hosts and FC-NVME
17  *  targets to perform FC-NVME LS requests or transmit
18  *  responses.
19  *
20  * ***********************************************************
21  */
22 
23 /**
24  * struct nvmefc_ls_req - Request structure passed from the transport
25  *            to the LLDD to perform a NVME-FC LS request and obtain
26  *            a response.
27  *            Used by nvme-fc transport (host) to send LS's such as
28  *              Create Association, Create Connection and Disconnect
29  *              Association.
30  *            Used by the nvmet-fc transport (controller) to send
31  *              LS's such as Disconnect Association.
32  *
33  * Values set by the requestor prior to calling the LLDD ls_req entrypoint:
34  * @rqstaddr: pointer to request buffer
35  * @rqstdma:  PCI DMA address of request buffer
36  * @rqstlen:  Length, in bytes, of request buffer
37  * @rspaddr:  pointer to response buffer
38  * @rspdma:   PCI DMA address of response buffer
39  * @rsplen:   Length, in bytes, of response buffer
40  * @timeout:  Maximum amount of time, in seconds, to wait for the LS response.
41  *            If timeout exceeded, LLDD to abort LS exchange and complete
42  *            LS request with error status.
43  * @private:  pointer to memory allocated alongside the ls request structure
44  *            that is specifically for the LLDD to use while processing the
45  *            request. The length of the buffer corresponds to the
46  *            lsrqst_priv_sz value specified in the xxx_template supplied
47  *            by the LLDD.
48  * @done:     The callback routine the LLDD is to invoke upon completion of
49  *            the LS request. req argument is the pointer to the original LS
50  *            request structure. Status argument must be 0 upon success, a
51  *            negative errno on failure (example: -ENXIO).
52  */
53 struct nvmefc_ls_req {
54 	void			*rqstaddr;
55 	dma_addr_t		rqstdma;
56 	u32			rqstlen;
57 	void			*rspaddr;
58 	dma_addr_t		rspdma;
59 	u32			rsplen;
60 	u32			timeout;
61 
62 	void			*private;
63 
64 	void (*done)(struct nvmefc_ls_req *req, int status);
65 
66 } __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
67 
68 
69 /**
70  * struct nvmefc_ls_rsp - Structure passed from the transport to the LLDD
71  *            to request the transmit the NVME-FC LS response to a
72  *            NVME-FC LS request.   The structure originates in the LLDD
73  *            and is given to the transport via the xxx_rcv_ls_req()
74  *            transport routine. As such, the structure represents the
75  *            FC exchange context for the NVME-FC LS request that was
76  *            received and which the response is to be sent for.
77  *            Used by the LLDD to pass the nvmet-fc transport (controller)
78  *              received LS's such as Create Association, Create Connection
79  *              and Disconnect Association.
80  *            Used by the LLDD to pass the nvme-fc transport (host)
81  *              received LS's such as Disconnect Association or Disconnect
82  *              Connection.
83  *
84  * The structure is allocated by the LLDD whenever a LS Request is received
85  * from the FC link. The address of the structure is passed to the nvmet-fc
86  * or nvme-fc layer via the xxx_rcv_ls_req() transport routines.
87  *
88  * The address of the structure is to be passed back to the LLDD
89  * when the response is to be transmit. The LLDD will use the address to
90  * map back to the LLDD exchange structure which maintains information such
91  * the remote N_Port that sent the LS as well as any FC exchange context.
92  * Upon completion of the LS response transmit, the LLDD will pass the
93  * address of the structure back to the transport LS rsp done() routine,
94  * allowing the transport release dma resources. Upon completion of
95  * the done() routine, no further access to the structure will be made by
96  * the transport and the LLDD can de-allocate the structure.
97  *
98  * Field initialization:
99  *   At the time of the xxx_rcv_ls_req() call, there is no content that
100  *     is valid in the structure.
101  *
102  *   When the structure is used for the LLDD->xmt_ls_rsp() call, the
103  *     transport layer will fully set the fields in order to specify the
104  *     response payload buffer and its length as well as the done routine
105  *     to be called upon completion of the transmit.  The transport layer
106  *     will also set a private pointer for its own use in the done routine.
107  *
108  * Values set by the transport layer prior to calling the LLDD xmt_ls_rsp
109  * entrypoint:
110  * @rspbuf:   pointer to the LS response buffer
111  * @rspdma:   PCI DMA address of the LS response buffer
112  * @rsplen:   Length, in bytes, of the LS response buffer
113  * @done:     The callback routine the LLDD is to invoke upon completion of
114  *            transmitting the LS response. req argument is the pointer to
115  *            the original ls request.
116  * @nvme_fc_private:  pointer to an internal transport-specific structure
117  *            used as part of the transport done() processing. The LLDD is
118  *            not to access this pointer.
119  */
120 struct nvmefc_ls_rsp {
121 	void		*rspbuf;
122 	dma_addr_t	rspdma;
123 	u16		rsplen;
124 
125 	void (*done)(struct nvmefc_ls_rsp *rsp);
126 	void		*nvme_fc_private;	/* LLDD is not to access !! */
127 };
128 
129 
130 
131 /*
132  * **********************  LLDD FC-NVME Host API ********************
133  *
134  *  For FC LLDD's that are the NVME Host role.
135  *
136  * ******************************************************************
137  */
138 
139 
140 /**
141  * struct nvme_fc_port_info - port-specific ids and FC connection-specific
142  *                            data element used during NVME Host role
143  *                            registrations
144  *
145  * Static fields describing the port being registered:
146  * @node_name: FC WWNN for the port
147  * @port_name: FC WWPN for the port
148  * @port_role: What NVME roles are supported (see FC_PORT_ROLE_xxx)
149  * @dev_loss_tmo: maximum delay for reconnects to an association on
150  *             this device. Used only on a remoteport.
151  *
152  * Initialization values for dynamic port fields:
153  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
154  *                be set to 0.
155  */
156 struct nvme_fc_port_info {
157 	u64			node_name;
158 	u64			port_name;
159 	u32			port_role;
160 	u32			port_id;
161 	u32			dev_loss_tmo;
162 };
163 
164 enum nvmefc_fcp_datadir {
165 	NVMEFC_FCP_NODATA,	/* payload_length and sg_cnt will be zero */
166 	NVMEFC_FCP_WRITE,
167 	NVMEFC_FCP_READ,
168 };
169 
170 
171 /**
172  * struct nvmefc_fcp_req - Request structure passed from NVME-FC transport
173  *                         to LLDD in order to perform a NVME FCP IO operation.
174  *
175  * Values set by the NVME-FC layer prior to calling the LLDD fcp_io
176  * entrypoint.
177  * @cmdaddr:   pointer to the FCP CMD IU buffer
178  * @rspaddr:   pointer to the FCP RSP IU buffer
179  * @cmddma:    PCI DMA address of the FCP CMD IU buffer
180  * @rspdma:    PCI DMA address of the FCP RSP IU buffer
181  * @cmdlen:    Length, in bytes, of the FCP CMD IU buffer
182  * @rsplen:    Length, in bytes, of the FCP RSP IU buffer
183  * @payload_length: Length of DATA_IN or DATA_OUT payload data to transfer
184  * @sg_table:  scatter/gather structure for payload data
185  * @first_sgl: memory for 1st scatter/gather list segment for payload data
186  * @sg_cnt:    number of elements in the scatter/gather list
187  * @io_dir:    direction of the FCP request (see NVMEFC_FCP_xxx)
188  * @sqid:      The nvme SQID the command is being issued on
189  * @done:      The callback routine the LLDD is to invoke upon completion of
190  *             the FCP operation. req argument is the pointer to the original
191  *             FCP IO operation.
192  * @private:   pointer to memory allocated alongside the FCP operation
193  *             request structure that is specifically for the LLDD to use
194  *             while processing the operation. The length of the buffer
195  *             corresponds to the fcprqst_priv_sz value specified in the
196  *             nvme_fc_port_template supplied by the LLDD.
197  *
198  * Values set by the LLDD indicating completion status of the FCP operation.
199  * Must be set prior to calling the done() callback.
200  * @transferred_length: amount of payload data, in bytes, that were
201  *             transferred. Should equal payload_length on success.
202  * @rcv_rsplen: length, in bytes, of the FCP RSP IU received.
203  * @status:    Completion status of the FCP operation. must be 0 upon success,
204  *             negative errno value upon failure (ex: -EIO). Note: this is
205  *             NOT a reflection of the NVME CQE completion status. Only the
206  *             status of the FCP operation at the NVME-FC level.
207  */
208 struct nvmefc_fcp_req {
209 	void			*cmdaddr;
210 	void			*rspaddr;
211 	dma_addr_t		cmddma;
212 	dma_addr_t		rspdma;
213 	u16			cmdlen;
214 	u16			rsplen;
215 
216 	u32			payload_length;
217 	struct sg_table		sg_table;
218 	struct scatterlist	*first_sgl;
219 	int			sg_cnt;
220 	enum nvmefc_fcp_datadir	io_dir;
221 
222 	__le16			sqid;
223 
224 	void (*done)(struct nvmefc_fcp_req *req);
225 
226 	void			*private;
227 
228 	u32			transferred_length;
229 	u16			rcv_rsplen;
230 	u32			status;
231 } __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
232 
233 
234 /*
235  * Direct copy of fc_port_state enum. For later merging
236  */
237 enum nvme_fc_obj_state {
238 	FC_OBJSTATE_UNKNOWN,
239 	FC_OBJSTATE_NOTPRESENT,
240 	FC_OBJSTATE_ONLINE,
241 	FC_OBJSTATE_OFFLINE,		/* User has taken Port Offline */
242 	FC_OBJSTATE_BLOCKED,
243 	FC_OBJSTATE_BYPASSED,
244 	FC_OBJSTATE_DIAGNOSTICS,
245 	FC_OBJSTATE_LINKDOWN,
246 	FC_OBJSTATE_ERROR,
247 	FC_OBJSTATE_LOOPBACK,
248 	FC_OBJSTATE_DELETED,
249 };
250 
251 
252 /**
253  * struct nvme_fc_local_port - structure used between NVME-FC transport and
254  *                 a LLDD to reference a local NVME host port.
255  *                 Allocated/created by the nvme_fc_register_localport()
256  *                 transport interface.
257  *
258  * Fields with static values for the port. Initialized by the
259  * port_info struct supplied to the registration call.
260  * @port_num:  NVME-FC transport host port number
261  * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx)
262  * @node_name: FC WWNN for the port
263  * @port_name: FC WWPN for the port
264  * @private:   pointer to memory allocated alongside the local port
265  *             structure that is specifically for the LLDD to use.
266  *             The length of the buffer corresponds to the local_priv_sz
267  *             value specified in the nvme_fc_port_template supplied by
268  *             the LLDD.
269  * @dev_loss_tmo: maximum delay for reconnects to an association on
270  *             this device. To modify, lldd must call
271  *             nvme_fc_set_remoteport_devloss().
272  *
273  * Fields with dynamic values. Values may change base on link state. LLDD
274  * may reference fields directly to change them. Initialized by the
275  * port_info struct supplied to the registration call.
276  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
277  *                be set to 0.
278  * @port_state:   Operational state of the port.
279  */
280 struct nvme_fc_local_port {
281 	/* static/read-only fields */
282 	u32 port_num;
283 	u32 port_role;
284 	u64 node_name;
285 	u64 port_name;
286 
287 	void *private;
288 
289 	/* dynamic fields */
290 	u32 port_id;
291 	enum nvme_fc_obj_state port_state;
292 } __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
293 
294 
295 /**
296  * struct nvme_fc_remote_port - structure used between NVME-FC transport and
297  *                 a LLDD to reference a remote NVME subsystem port.
298  *                 Allocated/created by the nvme_fc_register_remoteport()
299  *                 transport interface.
300  *
301  * Fields with static values for the port. Initialized by the
302  * port_info struct supplied to the registration call.
303  * @port_num:  NVME-FC transport remote subsystem port number
304  * @port_role: NVME roles are supported on the port (see FC_PORT_ROLE_xxx)
305  * @node_name: FC WWNN for the port
306  * @port_name: FC WWPN for the port
307  * @localport: pointer to the NVME-FC local host port the subsystem is
308  *             connected to.
309  * @private:   pointer to memory allocated alongside the remote port
310  *             structure that is specifically for the LLDD to use.
311  *             The length of the buffer corresponds to the remote_priv_sz
312  *             value specified in the nvme_fc_port_template supplied by
313  *             the LLDD.
314  *
315  * Fields with dynamic values. Values may change base on link or login
316  * state. LLDD may reference fields directly to change them. Initialized by
317  * the port_info struct supplied to the registration call.
318  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
319  *                be set to 0.
320  * @port_state:   Operational state of the remote port. Valid values are
321  *                ONLINE or UNKNOWN.
322  */
323 struct nvme_fc_remote_port {
324 	/* static fields */
325 	u32 port_num;
326 	u32 port_role;
327 	u64 node_name;
328 	u64 port_name;
329 	struct nvme_fc_local_port *localport;
330 	void *private;
331 	u32 dev_loss_tmo;
332 
333 	/* dynamic fields */
334 	u32 port_id;
335 	enum nvme_fc_obj_state port_state;
336 } __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
337 
338 
339 /**
340  * struct nvme_fc_port_template - structure containing static entrypoints and
341  *                 operational parameters for an LLDD that supports NVME host
342  *                 behavior. Passed by reference in port registrations.
343  *                 NVME-FC transport remembers template reference and may
344  *                 access it during runtime operation.
345  *
346  * Host/Initiator Transport Entrypoints/Parameters:
347  *
348  * @localport_delete:  The LLDD initiates deletion of a localport via
349  *       nvme_fc_deregister_localport(). However, the teardown is
350  *       asynchronous. This routine is called upon the completion of the
351  *       teardown to inform the LLDD that the localport has been deleted.
352  *       Entrypoint is Mandatory.
353  *
354  * @remoteport_delete:  The LLDD initiates deletion of a remoteport via
355  *       nvme_fc_deregister_remoteport(). However, the teardown is
356  *       asynchronous. This routine is called upon the completion of the
357  *       teardown to inform the LLDD that the remoteport has been deleted.
358  *       Entrypoint is Mandatory.
359  *
360  * @create_queue:  Upon creating a host<->controller association, queues are
361  *       created such that they can be affinitized to cpus/cores. This
362  *       callback into the LLDD to notify that a controller queue is being
363  *       created.  The LLDD may choose to allocate an associated hw queue
364  *       or map it onto a shared hw queue. Upon return from the call, the
365  *       LLDD specifies a handle that will be given back to it for any
366  *       command that is posted to the controller queue.  The handle can
367  *       be used by the LLDD to map quickly to the proper hw queue for
368  *       command execution.  The mask of cpu's that will map to this queue
369  *       at the block-level is also passed in. The LLDD should use the
370  *       queue id and/or cpu masks to ensure proper affinitization of the
371  *       controller queue to the hw queue.
372  *       Entrypoint is Optional.
373  *
374  * @delete_queue:  This is the inverse of the crete_queue. During
375  *       host<->controller association teardown, this routine is called
376  *       when a controller queue is being terminated. Any association with
377  *       a hw queue should be termined. If there is a unique hw queue, the
378  *       hw queue should be torn down.
379  *       Entrypoint is Optional.
380  *
381  * @poll_queue:  Called to poll for the completion of an io on a blk queue.
382  *       Entrypoint is Optional.
383  *
384  * @ls_req:  Called to issue a FC-NVME FC-4 LS service request.
385  *       The nvme_fc_ls_req structure will fully describe the buffers for
386  *       the request payload and where to place the response payload. The
387  *       LLDD is to allocate an exchange, issue the LS request, obtain the
388  *       LS response, and call the "done" routine specified in the request
389  *       structure (argument to done is the ls request structure itself).
390  *       Entrypoint is Mandatory.
391  *
392  * @fcp_io:  called to issue a FC-NVME I/O request.  The I/O may be for
393  *       an admin queue or an i/o queue.  The nvmefc_fcp_req structure will
394  *       fully describe the io: the buffer containing the FC-NVME CMD IU
395  *       (which contains the SQE), the sg list for the payload if applicable,
396  *       and the buffer to place the FC-NVME RSP IU into.  The LLDD will
397  *       complete the i/o, indicating the amount of data transferred or
398  *       any transport error, and call the "done" routine specified in the
399  *       request structure (argument to done is the fcp request structure
400  *       itself).
401  *       Entrypoint is Mandatory.
402  *
403  * @ls_abort: called to request the LLDD to abort the indicated ls request.
404  *       The call may return before the abort has completed. After aborting
405  *       the request, the LLDD must still call the ls request done routine
406  *       indicating an FC transport Aborted status.
407  *       Entrypoint is Mandatory.
408  *
409  * @fcp_abort: called to request the LLDD to abort the indicated fcp request.
410  *       The call may return before the abort has completed. After aborting
411  *       the request, the LLDD must still call the fcp request done routine
412  *       indicating an FC transport Aborted status.
413  *       Entrypoint is Mandatory.
414  *
415  * @xmt_ls_rsp:  Called to transmit the response to a FC-NVME FC-4 LS service.
416  *       The nvmefc_ls_rsp structure is the same LLDD-supplied exchange
417  *       structure specified in the nvme_fc_rcv_ls_req() call made when
418  *       the LS request was received. The structure will fully describe
419  *       the buffers for the response payload and the dma address of the
420  *       payload. The LLDD is to transmit the response (or return a
421  *       non-zero errno status), and upon completion of the transmit, call
422  *       the "done" routine specified in the nvmefc_ls_rsp structure
423  *       (argument to done is the address of the nvmefc_ls_rsp structure
424  *       itself). Upon the completion of the done routine, the LLDD shall
425  *       consider the LS handling complete and the nvmefc_ls_rsp structure
426  *       may be freed/released.
427  *       Entrypoint is mandatory if the LLDD calls the nvme_fc_rcv_ls_req()
428  *       entrypoint.
429  *
430  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
431  *       supports for cpu affinitization.
432  *       Value is Mandatory. Must be at least 1.
433  *
434  * @max_sgl_segments:  indicates the maximum number of sgl segments supported
435  *       by the LLDD
436  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
437  *
438  * @max_dif_sgl_segments:  indicates the maximum number of sgl segments
439  *       supported by the LLDD for DIF operations.
440  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
441  *
442  * @dma_boundary:  indicates the dma address boundary where dma mappings
443  *       will be split across.
444  *       Value is Mandatory. Typical value is 0xFFFFFFFF to split across
445  *       4Gig address boundarys
446  *
447  * @local_priv_sz: The LLDD sets this field to the amount of additional
448  *       memory that it would like fc nvme layer to allocate on the LLDD's
449  *       behalf whenever a localport is allocated.  The additional memory
450  *       area solely for the of the LLDD and its location is specified by
451  *       the localport->private pointer.
452  *       Value is Mandatory. Allowed to be zero.
453  *
454  * @remote_priv_sz: The LLDD sets this field to the amount of additional
455  *       memory that it would like fc nvme layer to allocate on the LLDD's
456  *       behalf whenever a remoteport is allocated.  The additional memory
457  *       area solely for the of the LLDD and its location is specified by
458  *       the remoteport->private pointer.
459  *       Value is Mandatory. Allowed to be zero.
460  *
461  * @lsrqst_priv_sz: The LLDD sets this field to the amount of additional
462  *       memory that it would like fc nvme layer to allocate on the LLDD's
463  *       behalf whenever a ls request structure is allocated. The additional
464  *       memory area is solely for use by the LLDD and its location is
465  *       specified by the ls_request->private pointer.
466  *       Value is Mandatory. Allowed to be zero.
467  *
468  * @fcprqst_priv_sz: The LLDD sets this field to the amount of additional
469  *       memory that it would like fc nvme layer to allocate on the LLDD's
470  *       behalf whenever a fcp request structure is allocated. The additional
471  *       memory area solely for the of the LLDD and its location is
472  *       specified by the fcp_request->private pointer.
473  *       Value is Mandatory. Allowed to be zero.
474  */
475 struct nvme_fc_port_template {
476 	/* initiator-based functions */
477 	void	(*localport_delete)(struct nvme_fc_local_port *);
478 	void	(*remoteport_delete)(struct nvme_fc_remote_port *);
479 	int	(*create_queue)(struct nvme_fc_local_port *,
480 				unsigned int qidx, u16 qsize,
481 				void **handle);
482 	void	(*delete_queue)(struct nvme_fc_local_port *,
483 				unsigned int qidx, void *handle);
484 	int	(*ls_req)(struct nvme_fc_local_port *,
485 				struct nvme_fc_remote_port *,
486 				struct nvmefc_ls_req *);
487 	int	(*fcp_io)(struct nvme_fc_local_port *,
488 				struct nvme_fc_remote_port *,
489 				void *hw_queue_handle,
490 				struct nvmefc_fcp_req *);
491 	void	(*ls_abort)(struct nvme_fc_local_port *,
492 				struct nvme_fc_remote_port *,
493 				struct nvmefc_ls_req *);
494 	void	(*fcp_abort)(struct nvme_fc_local_port *,
495 				struct nvme_fc_remote_port *,
496 				void *hw_queue_handle,
497 				struct nvmefc_fcp_req *);
498 	int	(*xmt_ls_rsp)(struct nvme_fc_local_port *localport,
499 				struct nvme_fc_remote_port *rport,
500 				struct nvmefc_ls_rsp *ls_rsp);
501 	void	(*map_queues)(struct nvme_fc_local_port *localport,
502 			      struct blk_mq_queue_map *map);
503 
504 	u32	max_hw_queues;
505 	u16	max_sgl_segments;
506 	u16	max_dif_sgl_segments;
507 	u64	dma_boundary;
508 
509 	/* sizes of additional private data for data structures */
510 	u32	local_priv_sz;
511 	u32	remote_priv_sz;
512 	u32	lsrqst_priv_sz;
513 	u32	fcprqst_priv_sz;
514 };
515 
516 
517 /*
518  * Initiator/Host functions
519  */
520 
521 int nvme_fc_register_localport(struct nvme_fc_port_info *pinfo,
522 			struct nvme_fc_port_template *template,
523 			struct device *dev,
524 			struct nvme_fc_local_port **lport_p);
525 
526 int nvme_fc_unregister_localport(struct nvme_fc_local_port *localport);
527 
528 int nvme_fc_register_remoteport(struct nvme_fc_local_port *localport,
529 			struct nvme_fc_port_info *pinfo,
530 			struct nvme_fc_remote_port **rport_p);
531 
532 int nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *remoteport);
533 
534 void nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport);
535 
536 int nvme_fc_set_remoteport_devloss(struct nvme_fc_remote_port *remoteport,
537 			u32 dev_loss_tmo);
538 
539 /*
540  * Routine called to pass a NVME-FC LS request, received by the lldd,
541  * to the nvme-fc transport.
542  *
543  * If the return value is zero: the LS was successfully accepted by the
544  *   transport.
545  * If the return value is non-zero: the transport has not accepted the
546  *   LS. The lldd should ABTS-LS the LS.
547  *
548  * Note: if the LLDD receives and ABTS for the LS prior to the transport
549  * calling the ops->xmt_ls_rsp() routine to transmit a response, the LLDD
550  * shall mark the LS as aborted, and when the xmt_ls_rsp() is called: the
551  * response shall not be transmit and the struct nvmefc_ls_rsp() done
552  * routine shall be called.  The LLDD may transmit the ABTS response as
553  * soon as the LS was marked or can delay until the xmt_ls_rsp() call is
554  * made.
555  * Note: if an RCV LS was successfully posted to the transport and the
556  * remoteport is then unregistered before xmt_ls_rsp() was called for
557  * the lsrsp structure, the transport will still call xmt_ls_rsp()
558  * afterward to cleanup the outstanding lsrsp structure. The LLDD should
559  * noop the transmission of the rsp and call the lsrsp->done() routine
560  * to allow the lsrsp structure to be released.
561  */
562 int nvme_fc_rcv_ls_req(struct nvme_fc_remote_port *remoteport,
563 			struct nvmefc_ls_rsp *lsrsp,
564 			void *lsreqbuf, u32 lsreqbuf_len);
565 
566 
567 /*
568  * Routine called to get the appid field associated with request by the lldd
569  *
570  * If the return value is NULL : the user/libvirt has not set the appid to VM
571  * If the return value is non-zero: Returns the appid associated with VM
572  *
573  * @req: IO request from nvme fc to driver
574  */
575 char *nvme_fc_io_getuuid(struct nvmefc_fcp_req *req);
576 
577 /*
578  * ***************  LLDD FC-NVME Target/Subsystem API ***************
579  *
580  *  For FC LLDD's that are the NVME Subsystem role
581  *
582  * ******************************************************************
583  */
584 
585 /**
586  * struct nvmet_fc_port_info - port-specific ids and FC connection-specific
587  *                             data element used during NVME Subsystem role
588  *                             registrations
589  *
590  * Static fields describing the port being registered:
591  * @node_name: FC WWNN for the port
592  * @port_name: FC WWPN for the port
593  *
594  * Initialization values for dynamic port fields:
595  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
596  *                be set to 0.
597  */
598 struct nvmet_fc_port_info {
599 	u64			node_name;
600 	u64			port_name;
601 	u32			port_id;
602 };
603 
604 
605 /* Operations that NVME-FC layer may request the LLDD to perform for FCP */
606 enum {
607 	NVMET_FCOP_READDATA	= 1,	/* xmt data to initiator */
608 	NVMET_FCOP_WRITEDATA	= 2,	/* xmt data from initiator */
609 	NVMET_FCOP_READDATA_RSP	= 3,	/* xmt data to initiator and send
610 					 * rsp as well
611 					 */
612 	NVMET_FCOP_RSP		= 4,	/* send rsp frame */
613 };
614 
615 /**
616  * struct nvmefc_tgt_fcp_req - Structure used between LLDD and NVMET-FC
617  *                            layer to represent the exchange context and
618  *                            the specific FC-NVME IU operation(s) to perform
619  *                            for a FC-NVME FCP IO.
620  *
621  * Structure used between LLDD and nvmet-fc layer to represent the exchange
622  * context for a FC-NVME FCP I/O operation (e.g. a nvme sqe, the sqe-related
623  * memory transfers, and its assocated cqe transfer).
624  *
625  * The structure is allocated by the LLDD whenever a FCP CMD IU is received
626  * from the FC link. The address of the structure is passed to the nvmet-fc
627  * layer via the nvmet_fc_rcv_fcp_req() call. The address of the structure
628  * will be passed back to the LLDD for the data operations and transmit of
629  * the response. The LLDD is to use the address to map back to the LLDD
630  * exchange structure which maintains information such as the targetport
631  * the FCP I/O was received on, the remote FC NVME initiator that sent the
632  * FCP I/O, and any FC exchange context.  Upon completion of the FCP target
633  * operation, the address of the structure will be passed back to the FCP
634  * op done() routine, allowing the nvmet-fc layer to release dma resources.
635  * Upon completion of the done() routine for either RSP or ABORT ops, no
636  * further access will be made by the nvmet-fc layer and the LLDD can
637  * de-allocate the structure.
638  *
639  * Field initialization:
640  *   At the time of the nvmet_fc_rcv_fcp_req() call, there is no content that
641  *     is valid in the structure.
642  *
643  *   When the structure is used for an FCP target operation, the nvmet-fc
644  *     layer will fully set the fields in order to specify the scattergather
645  *     list, the transfer length, as well as the done routine to be called
646  *     upon compeletion of the operation.  The nvmet-fc layer will also set a
647  *     private pointer for its own use in the done routine.
648  *
649  * Values set by the NVMET-FC layer prior to calling the LLDD fcp_op
650  * entrypoint.
651  * @op:       Indicates the FCP IU operation to perform (see NVMET_FCOP_xxx)
652  * @hwqid:    Specifies the hw queue index (0..N-1, where N is the
653  *            max_hw_queues value from the LLD's nvmet_fc_target_template)
654  *            that the operation is to use.
655  * @offset:   Indicates the DATA_OUT/DATA_IN payload offset to be tranferred.
656  *            Field is only valid on WRITEDATA, READDATA, or READDATA_RSP ops.
657  * @timeout:  amount of time, in seconds, to wait for a response from the NVME
658  *            host. A value of 0 is an infinite wait.
659  *            Valid only for the following ops:
660  *              WRITEDATA: caps the wait for data reception
661  *              READDATA_RSP & RSP: caps wait for FCP_CONF reception (if used)
662  * @transfer_length: the length, in bytes, of the DATA_OUT or DATA_IN payload
663  *            that is to be transferred.
664  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
665  * @ba_rjt:   Contains the BA_RJT payload that is to be transferred.
666  *            Valid only for the NVMET_FCOP_BA_RJT op.
667  * @sg:       Scatter/gather list for the DATA_OUT/DATA_IN payload data.
668  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
669  * @sg_cnt:   Number of valid entries in the scatter/gather list.
670  *            Valid only for the WRITEDATA, READDATA, or READDATA_RSP ops.
671  * @rspaddr:  pointer to the FCP RSP IU buffer to be transmit
672  *            Used by RSP and READDATA_RSP ops
673  * @rspdma:   PCI DMA address of the FCP RSP IU buffer
674  *            Used by RSP and READDATA_RSP ops
675  * @rsplen:   Length, in bytes, of the FCP RSP IU buffer
676  *            Used by RSP and READDATA_RSP ops
677  * @done:     The callback routine the LLDD is to invoke upon completion of
678  *            the operation. req argument is the pointer to the original
679  *            FCP subsystem op request.
680  * @nvmet_fc_private:  pointer to an internal NVMET-FC layer structure used
681  *            as part of the NVMET-FC processing. The LLDD is not to
682  *            reference this field.
683  *
684  * Values set by the LLDD indicating completion status of the FCP operation.
685  * Must be set prior to calling the done() callback.
686  * @transferred_length: amount of DATA_OUT payload data received by a
687  *            WRITEDATA operation. If not a WRITEDATA operation, value must
688  *            be set to 0. Should equal transfer_length on success.
689  * @fcp_error: status of the FCP operation. Must be 0 on success; on failure
690  *            must be a NVME_SC_FC_xxxx value.
691  */
692 struct nvmefc_tgt_fcp_req {
693 	u8			op;
694 	u16			hwqid;
695 	u32			offset;
696 	u32			timeout;
697 	u32			transfer_length;
698 	struct fc_ba_rjt	ba_rjt;
699 	struct scatterlist	*sg;
700 	int			sg_cnt;
701 	void			*rspaddr;
702 	dma_addr_t		rspdma;
703 	u16			rsplen;
704 
705 	void (*done)(struct nvmefc_tgt_fcp_req *);
706 
707 	void *nvmet_fc_private;		/* LLDD is not to access !! */
708 
709 	u32			transferred_length;
710 	int			fcp_error;
711 };
712 
713 
714 /* Target Features (Bit fields) LLDD supports */
715 enum {
716 	NVMET_FCTGTFEAT_READDATA_RSP = (1 << 0),
717 		/* Bit 0: supports the NVMET_FCPOP_READDATA_RSP op, which
718 		 * sends (the last) Read Data sequence followed by the RSP
719 		 * sequence in one LLDD operation. Errors during Data
720 		 * sequence transmit must not allow RSP sequence to be sent.
721 		 */
722 };
723 
724 
725 /**
726  * struct nvmet_fc_target_port - structure used between NVME-FC transport and
727  *                 a LLDD to reference a local NVME subsystem port.
728  *                 Allocated/created by the nvme_fc_register_targetport()
729  *                 transport interface.
730  *
731  * Fields with static values for the port. Initialized by the
732  * port_info struct supplied to the registration call.
733  * @port_num:  NVME-FC transport subsystem port number
734  * @node_name: FC WWNN for the port
735  * @port_name: FC WWPN for the port
736  * @private:   pointer to memory allocated alongside the local port
737  *             structure that is specifically for the LLDD to use.
738  *             The length of the buffer corresponds to the target_priv_sz
739  *             value specified in the nvme_fc_target_template supplied by
740  *             the LLDD.
741  *
742  * Fields with dynamic values. Values may change base on link state. LLDD
743  * may reference fields directly to change them. Initialized by the
744  * port_info struct supplied to the registration call.
745  * @port_id:      FC N_Port_ID currently assigned the port. Upper 8 bits must
746  *                be set to 0.
747  * @port_state:   Operational state of the port.
748  */
749 struct nvmet_fc_target_port {
750 	/* static/read-only fields */
751 	u32 port_num;
752 	u64 node_name;
753 	u64 port_name;
754 
755 	void *private;
756 
757 	/* dynamic fields */
758 	u32 port_id;
759 	enum nvme_fc_obj_state port_state;
760 } __aligned(sizeof(u64));	/* alignment for other things alloc'd with */
761 
762 
763 /**
764  * struct nvmet_fc_target_template - structure containing static entrypoints
765  *                 and operational parameters for an LLDD that supports NVME
766  *                 subsystem behavior. Passed by reference in port
767  *                 registrations. NVME-FC transport remembers template
768  *                 reference and may access it during runtime operation.
769  *
770  * Subsystem/Target Transport Entrypoints/Parameters:
771  *
772  * @targetport_delete:  The LLDD initiates deletion of a targetport via
773  *       nvmet_fc_unregister_targetport(). However, the teardown is
774  *       asynchronous. This routine is called upon the completion of the
775  *       teardown to inform the LLDD that the targetport has been deleted.
776  *       Entrypoint is Mandatory.
777  *
778  * @xmt_ls_rsp:  Called to transmit the response to a FC-NVME FC-4 LS service.
779  *       The nvmefc_ls_rsp structure is the same LLDD-supplied exchange
780  *       structure specified in the nvmet_fc_rcv_ls_req() call made when
781  *       the LS request was received. The structure will fully describe
782  *       the buffers for the response payload and the dma address of the
783  *       payload. The LLDD is to transmit the response (or return a
784  *       non-zero errno status), and upon completion of the transmit, call
785  *       the "done" routine specified in the nvmefc_ls_rsp structure
786  *       (argument to done is the address of the nvmefc_ls_rsp structure
787  *       itself). Upon the completion of the done() routine, the LLDD shall
788  *       consider the LS handling complete and the nvmefc_ls_rsp structure
789  *       may be freed/released.
790  *       The transport will always call the xmt_ls_rsp() routine for any
791  *       LS received.
792  *       Entrypoint is Mandatory.
793  *
794  * @map_queues: This functions lets the driver expose the queue mapping
795  *	 to the block layer.
796  *       Entrypoint is Optional.
797  *
798  * @fcp_op:  Called to perform a data transfer or transmit a response.
799  *       The nvmefc_tgt_fcp_req structure is the same LLDD-supplied
800  *       exchange structure specified in the nvmet_fc_rcv_fcp_req() call
801  *       made when the FCP CMD IU was received. The op field in the
802  *       structure shall indicate the operation for the LLDD to perform
803  *       relative to the io.
804  *         NVMET_FCOP_READDATA operation: the LLDD is to send the
805  *           payload data (described by sglist) to the host in 1 or
806  *           more FC sequences (preferrably 1).  Note: the fc-nvme layer
807  *           may call the READDATA operation multiple times for longer
808  *           payloads.
809  *         NVMET_FCOP_WRITEDATA operation: the LLDD is to receive the
810  *           payload data (described by sglist) from the host via 1 or
811  *           more FC sequences (preferrably 1). The LLDD is to generate
812  *           the XFER_RDY IU(s) corresponding to the data being requested.
813  *           Note: the FC-NVME layer may call the WRITEDATA operation
814  *           multiple times for longer payloads.
815  *         NVMET_FCOP_READDATA_RSP operation: the LLDD is to send the
816  *           payload data (described by sglist) to the host in 1 or
817  *           more FC sequences (preferrably 1). If an error occurs during
818  *           payload data transmission, the LLDD is to set the
819  *           nvmefc_tgt_fcp_req fcp_error and transferred_length field, then
820  *           consider the operation complete. On error, the LLDD is to not
821  *           transmit the FCP_RSP iu. If all payload data is transferred
822  *           successfully, the LLDD is to update the nvmefc_tgt_fcp_req
823  *           transferred_length field and may subsequently transmit the
824  *           FCP_RSP iu payload (described by rspbuf, rspdma, rsplen).
825  *           If FCP_CONF is supported, the LLDD is to await FCP_CONF
826  *           reception to confirm the RSP reception by the host. The LLDD
827  *           may retramsit the FCP_RSP iu if necessary per FC-NVME. Upon
828  *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
829  *           or upon success/failure of FCP_CONF if it is supported, the
830  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
831  *           consider the operation complete.
832  *         NVMET_FCOP_RSP: the LLDD is to transmit the FCP_RSP iu payload
833  *           (described by rspbuf, rspdma, rsplen). If FCP_CONF is
834  *           supported, the LLDD is to await FCP_CONF reception to confirm
835  *           the RSP reception by the host. The LLDD may retramsit the
836  *           FCP_RSP iu if FCP_CONF is not received per FC-NVME. Upon
837  *           transmission of the FCP_RSP iu if FCP_CONF is not supported,
838  *           or upon success/failure of FCP_CONF if it is supported, the
839  *           LLDD is to set the nvmefc_tgt_fcp_req fcp_error field and
840  *           consider the operation complete.
841  *       Upon completing the indicated operation, the LLDD is to set the
842  *       status fields for the operation (tranferred_length and fcp_error
843  *       status) in the request, then call the "done" routine
844  *       indicated in the fcp request. After the operation completes,
845  *       regardless of whether the FCP_RSP iu was successfully transmit,
846  *       the LLDD-supplied exchange structure must remain valid until the
847  *       transport calls the fcp_req_release() callback to return ownership
848  *       of the exchange structure back to the LLDD so that it may be used
849  *       for another fcp command.
850  *       Note: when calling the done routine for READDATA or WRITEDATA
851  *       operations, the fc-nvme layer may immediate convert, in the same
852  *       thread and before returning to the LLDD, the fcp operation to
853  *       the next operation for the fcp io and call the LLDDs fcp_op
854  *       call again. If fields in the fcp request are to be accessed post
855  *       the done call, the LLDD should save their values prior to calling
856  *       the done routine, and inspect the save values after the done
857  *       routine.
858  *       Returns 0 on success, -<errno> on failure (Ex: -EIO)
859  *       Entrypoint is Mandatory.
860  *
861  * @fcp_abort:  Called by the transport to abort an active command.
862  *       The command may be in-between operations (nothing active in LLDD)
863  *       or may have an active WRITEDATA operation pending. The LLDD is to
864  *       initiate the ABTS process for the command and return from the
865  *       callback. The ABTS does not need to be complete on the command.
866  *       The fcp_abort callback inherently cannot fail. After the
867  *       fcp_abort() callback completes, the transport will wait for any
868  *       outstanding operation (if there was one) to complete, then will
869  *       call the fcp_req_release() callback to return the command's
870  *       exchange context back to the LLDD.
871  *       Entrypoint is Mandatory.
872  *
873  * @fcp_req_release:  Called by the transport to return a nvmefc_tgt_fcp_req
874  *       to the LLDD after all operations on the fcp operation are complete.
875  *       This may be due to the command completing or upon completion of
876  *       abort cleanup.
877  *       Entrypoint is Mandatory.
878  *
879  * @defer_rcv:  Called by the transport to signal the LLLD that it has
880  *       begun processing of a previously received NVME CMD IU. The LLDD
881  *       is now free to re-use the rcv buffer associated with the
882  *       nvmefc_tgt_fcp_req.
883  *       Entrypoint is Optional.
884  *
885  * @discovery_event:  Called by the transport to generate an RSCN
886  *       change notifications to NVME initiators. The RSCN notifications
887  *       should cause the initiator to rescan the discovery controller
888  *       on the targetport.
889  *
890  * @ls_req:  Called to issue a FC-NVME FC-4 LS service request.
891  *       The nvme_fc_ls_req structure will fully describe the buffers for
892  *       the request payload and where to place the response payload.
893  *       The targetport that is to issue the LS request is identified by
894  *       the targetport argument.  The remote port that is to receive the
895  *       LS request is identified by the hosthandle argument. The nvmet-fc
896  *       transport is only allowed to issue FC-NVME LS's on behalf of an
897  *       association that was created prior by a Create Association LS.
898  *       The hosthandle will originate from the LLDD in the struct
899  *       nvmefc_ls_rsp structure for the Create Association LS that
900  *       was delivered to the transport. The transport will save the
901  *       hosthandle as an attribute of the association.  If the LLDD
902  *       loses connectivity with the remote port, it must call the
903  *       nvmet_fc_invalidate_host() routine to remove any references to
904  *       the remote port in the transport.
905  *       The LLDD is to allocate an exchange, issue the LS request, obtain
906  *       the LS response, and call the "done" routine specified in the
907  *       request structure (argument to done is the ls request structure
908  *       itself).
909  *       Entrypoint is Optional - but highly recommended.
910  *
911  * @ls_abort: called to request the LLDD to abort the indicated ls request.
912  *       The call may return before the abort has completed. After aborting
913  *       the request, the LLDD must still call the ls request done routine
914  *       indicating an FC transport Aborted status.
915  *       Entrypoint is Mandatory if the ls_req entry point is specified.
916  *
917  * @host_release: called to inform the LLDD that the request to invalidate
918  *       the host port indicated by the hosthandle has been fully completed.
919  *       No associations exist with the host port and there will be no
920  *       further references to hosthandle.
921  *       Entrypoint is Mandatory if the lldd calls nvmet_fc_invalidate_host().
922  *
923  * @max_hw_queues:  indicates the maximum number of hw queues the LLDD
924  *       supports for cpu affinitization.
925  *       Value is Mandatory. Must be at least 1.
926  *
927  * @max_sgl_segments:  indicates the maximum number of sgl segments supported
928  *       by the LLDD
929  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
930  *
931  * @max_dif_sgl_segments:  indicates the maximum number of sgl segments
932  *       supported by the LLDD for DIF operations.
933  *       Value is Mandatory. Must be at least 1. Recommend at least 256.
934  *
935  * @dma_boundary:  indicates the dma address boundary where dma mappings
936  *       will be split across.
937  *       Value is Mandatory. Typical value is 0xFFFFFFFF to split across
938  *       4Gig address boundarys
939  *
940  * @target_features: The LLDD sets bits in this field to correspond to
941  *       optional features that are supported by the LLDD.
942  *       Refer to the NVMET_FCTGTFEAT_xxx values.
943  *       Value is Mandatory. Allowed to be zero.
944  *
945  * @target_priv_sz: The LLDD sets this field to the amount of additional
946  *       memory that it would like fc nvme layer to allocate on the LLDD's
947  *       behalf whenever a targetport is allocated.  The additional memory
948  *       area solely for the of the LLDD and its location is specified by
949  *       the targetport->private pointer.
950  *       Value is Mandatory. Allowed to be zero.
951  *
952  * @lsrqst_priv_sz: The LLDD sets this field to the amount of additional
953  *       memory that it would like nvmet-fc layer to allocate on the LLDD's
954  *       behalf whenever a ls request structure is allocated. The additional
955  *       memory area is solely for use by the LLDD and its location is
956  *       specified by the ls_request->private pointer.
957  *       Value is Mandatory. Allowed to be zero.
958  *
959  */
960 struct nvmet_fc_target_template {
961 	void (*targetport_delete)(struct nvmet_fc_target_port *tgtport);
962 	int (*xmt_ls_rsp)(struct nvmet_fc_target_port *tgtport,
963 				struct nvmefc_ls_rsp *ls_rsp);
964 	int (*fcp_op)(struct nvmet_fc_target_port *tgtport,
965 				struct nvmefc_tgt_fcp_req *fcpreq);
966 	void (*fcp_abort)(struct nvmet_fc_target_port *tgtport,
967 				struct nvmefc_tgt_fcp_req *fcpreq);
968 	void (*fcp_req_release)(struct nvmet_fc_target_port *tgtport,
969 				struct nvmefc_tgt_fcp_req *fcpreq);
970 	void (*defer_rcv)(struct nvmet_fc_target_port *tgtport,
971 				struct nvmefc_tgt_fcp_req *fcpreq);
972 	void (*discovery_event)(struct nvmet_fc_target_port *tgtport);
973 	int  (*ls_req)(struct nvmet_fc_target_port *targetport,
974 				void *hosthandle, struct nvmefc_ls_req *lsreq);
975 	void (*ls_abort)(struct nvmet_fc_target_port *targetport,
976 				void *hosthandle, struct nvmefc_ls_req *lsreq);
977 	void (*host_release)(void *hosthandle);
978 
979 	u32	max_hw_queues;
980 	u16	max_sgl_segments;
981 	u16	max_dif_sgl_segments;
982 	u64	dma_boundary;
983 
984 	u32	target_features;
985 
986 	/* sizes of additional private data for data structures */
987 	u32	target_priv_sz;
988 	u32	lsrqst_priv_sz;
989 };
990 
991 
992 int nvmet_fc_register_targetport(struct nvmet_fc_port_info *portinfo,
993 			struct nvmet_fc_target_template *template,
994 			struct device *dev,
995 			struct nvmet_fc_target_port **tgtport_p);
996 
997 int nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *tgtport);
998 
999 /*
1000  * Routine called to pass a NVME-FC LS request, received by the lldd,
1001  * to the nvmet-fc transport.
1002  *
1003  * If the return value is zero: the LS was successfully accepted by the
1004  *   transport.
1005  * If the return value is non-zero: the transport has not accepted the
1006  *   LS. The lldd should ABTS-LS the LS.
1007  *
1008  * Note: if the LLDD receives and ABTS for the LS prior to the transport
1009  * calling the ops->xmt_ls_rsp() routine to transmit a response, the LLDD
1010  * shall mark the LS as aborted, and when the xmt_ls_rsp() is called: the
1011  * response shall not be transmit and the struct nvmefc_ls_rsp() done
1012  * routine shall be called.  The LLDD may transmit the ABTS response as
1013  * soon as the LS was marked or can delay until the xmt_ls_rsp() call is
1014  * made.
1015  * Note: if an RCV LS was successfully posted to the transport and the
1016  * targetport is then unregistered before xmt_ls_rsp() was called for
1017  * the lsrsp structure, the transport will still call xmt_ls_rsp()
1018  * afterward to cleanup the outstanding lsrsp structure. The LLDD should
1019  * noop the transmission of the rsp and call the lsrsp->done() routine
1020  * to allow the lsrsp structure to be released.
1021  */
1022 int nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *tgtport,
1023 			void *hosthandle,
1024 			struct nvmefc_ls_rsp *rsp,
1025 			void *lsreqbuf, u32 lsreqbuf_len);
1026 
1027 /*
1028  * Routine called by the LLDD whenever it has a logout or loss of
1029  * connectivity to a NVME-FC host port which there had been active
1030  * NVMe controllers for.  The host port is indicated by the
1031  * hosthandle. The hosthandle is given to the nvmet-fc transport
1032  * when a NVME LS was received, typically to create a new association.
1033  * The nvmet-fc transport will cache the hostport value with the
1034  * association for use in LS requests for the association.
1035  * When the LLDD calls this routine, the nvmet-fc transport will
1036  * immediately terminate all associations that were created with
1037  * the hosthandle host port.
1038  * The LLDD, after calling this routine and having control returned,
1039  * must assume the transport may subsequently utilize hosthandle as
1040  * part of sending LS's to terminate the association.  The LLDD
1041  * should reject the LS's if they are attempted.
1042  * Once the last association has terminated for the hosthandle host
1043  * port, the nvmet-fc transport will call the ops->host_release()
1044  * callback. As of the callback, the nvmet-fc transport will no
1045  * longer reference hosthandle.
1046  */
1047 void nvmet_fc_invalidate_host(struct nvmet_fc_target_port *tgtport,
1048 			void *hosthandle);
1049 
1050 /*
1051  * If nvmet_fc_rcv_fcp_req returns non-zero, the transport has not accepted
1052  * the FCP cmd. The lldd should ABTS-LS the cmd.
1053  */
1054 int nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *tgtport,
1055 			struct nvmefc_tgt_fcp_req *fcpreq,
1056 			void *cmdiubuf, u32 cmdiubuf_len);
1057 
1058 void nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *tgtport,
1059 			struct nvmefc_tgt_fcp_req *fcpreq);
1060 /*
1061  * add a define, visible to the compiler, that indicates support
1062  * for feature. Allows for conditional compilation in LLDDs.
1063  */
1064 #define NVME_FC_FEAT_UUID	0x0001
1065 
1066 #endif /* _NVME_FC_DRIVER_H */
1067