xref: /linux/drivers/nvme/target/fc.c (revision e91c37f1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2016 Avago Technologies.  All rights reserved.
4  */
5 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
6 #include <linux/module.h>
7 #include <linux/slab.h>
8 #include <linux/blk-mq.h>
9 #include <linux/parser.h>
10 #include <linux/random.h>
11 #include <uapi/scsi/fc/fc_fs.h>
12 #include <uapi/scsi/fc/fc_els.h>
13 
14 #include "nvmet.h"
15 #include <linux/nvme-fc-driver.h>
16 #include <linux/nvme-fc.h>
17 #include "../host/fc.h"
18 
19 
20 /* *************************** Data Structures/Defines ****************** */
21 
22 
23 #define NVMET_LS_CTX_COUNT		256
24 
25 struct nvmet_fc_tgtport;
26 struct nvmet_fc_tgt_assoc;
27 
28 struct nvmet_fc_ls_iod {		/* for an LS RQST RCV */
29 	struct nvmefc_ls_rsp		*lsrsp;
30 	struct nvmefc_tgt_fcp_req	*fcpreq;	/* only if RS */
31 
32 	struct list_head		ls_rcv_list; /* tgtport->ls_rcv_list */
33 
34 	struct nvmet_fc_tgtport		*tgtport;
35 	struct nvmet_fc_tgt_assoc	*assoc;
36 	void				*hosthandle;
37 
38 	union nvmefc_ls_requests	*rqstbuf;
39 	union nvmefc_ls_responses	*rspbuf;
40 	u16				rqstdatalen;
41 	dma_addr_t			rspdma;
42 
43 	struct scatterlist		sg[2];
44 
45 	struct work_struct		work;
46 } __aligned(sizeof(unsigned long long));
47 
48 struct nvmet_fc_ls_req_op {		/* for an LS RQST XMT */
49 	struct nvmefc_ls_req		ls_req;
50 
51 	struct nvmet_fc_tgtport		*tgtport;
52 	void				*hosthandle;
53 
54 	int				ls_error;
55 	struct list_head		lsreq_list; /* tgtport->ls_req_list */
56 	bool				req_queued;
57 };
58 
59 
60 /* desired maximum for a single sequence - if sg list allows it */
61 #define NVMET_FC_MAX_SEQ_LENGTH		(256 * 1024)
62 
63 enum nvmet_fcp_datadir {
64 	NVMET_FCP_NODATA,
65 	NVMET_FCP_WRITE,
66 	NVMET_FCP_READ,
67 	NVMET_FCP_ABORTED,
68 };
69 
70 struct nvmet_fc_fcp_iod {
71 	struct nvmefc_tgt_fcp_req	*fcpreq;
72 
73 	struct nvme_fc_cmd_iu		cmdiubuf;
74 	struct nvme_fc_ersp_iu		rspiubuf;
75 	dma_addr_t			rspdma;
76 	struct scatterlist		*next_sg;
77 	struct scatterlist		*data_sg;
78 	int				data_sg_cnt;
79 	u32				offset;
80 	enum nvmet_fcp_datadir		io_dir;
81 	bool				active;
82 	bool				abort;
83 	bool				aborted;
84 	bool				writedataactive;
85 	spinlock_t			flock;
86 
87 	struct nvmet_req		req;
88 	struct work_struct		defer_work;
89 
90 	struct nvmet_fc_tgtport		*tgtport;
91 	struct nvmet_fc_tgt_queue	*queue;
92 
93 	struct list_head		fcp_list;	/* tgtport->fcp_list */
94 };
95 
96 struct nvmet_fc_tgtport {
97 	struct nvmet_fc_target_port	fc_target_port;
98 
99 	struct list_head		tgt_list; /* nvmet_fc_target_list */
100 	struct device			*dev;	/* dev for dma mapping */
101 	struct nvmet_fc_target_template	*ops;
102 
103 	struct nvmet_fc_ls_iod		*iod;
104 	spinlock_t			lock;
105 	struct list_head		ls_rcv_list;
106 	struct list_head		ls_req_list;
107 	struct list_head		ls_busylist;
108 	struct list_head		assoc_list;
109 	struct list_head		host_list;
110 	struct ida			assoc_cnt;
111 	struct nvmet_fc_port_entry	*pe;
112 	struct kref			ref;
113 	u32				max_sg_cnt;
114 
115 	struct work_struct		put_work;
116 };
117 
118 struct nvmet_fc_port_entry {
119 	struct nvmet_fc_tgtport		*tgtport;
120 	struct nvmet_port		*port;
121 	u64				node_name;
122 	u64				port_name;
123 	struct list_head		pe_list;
124 };
125 
126 struct nvmet_fc_defer_fcp_req {
127 	struct list_head		req_list;
128 	struct nvmefc_tgt_fcp_req	*fcp_req;
129 };
130 
131 struct nvmet_fc_tgt_queue {
132 	bool				ninetypercent;
133 	u16				qid;
134 	u16				sqsize;
135 	u16				ersp_ratio;
136 	__le16				sqhd;
137 	atomic_t			connected;
138 	atomic_t			sqtail;
139 	atomic_t			zrspcnt;
140 	atomic_t			rsn;
141 	spinlock_t			qlock;
142 	struct nvmet_cq			nvme_cq;
143 	struct nvmet_sq			nvme_sq;
144 	struct nvmet_fc_tgt_assoc	*assoc;
145 	struct list_head		fod_list;
146 	struct list_head		pending_cmd_list;
147 	struct list_head		avail_defer_list;
148 	struct workqueue_struct		*work_q;
149 	struct kref			ref;
150 	/* array of fcp_iods */
151 	struct nvmet_fc_fcp_iod		fod[] __counted_by(sqsize);
152 } __aligned(sizeof(unsigned long long));
153 
154 struct nvmet_fc_hostport {
155 	struct nvmet_fc_tgtport		*tgtport;
156 	void				*hosthandle;
157 	struct list_head		host_list;
158 	struct kref			ref;
159 	u8				invalid;
160 };
161 
162 struct nvmet_fc_tgt_assoc {
163 	u64				association_id;
164 	u32				a_id;
165 	atomic_t			terminating;
166 	struct nvmet_fc_tgtport		*tgtport;
167 	struct nvmet_fc_hostport	*hostport;
168 	struct nvmet_fc_ls_iod		*rcv_disconn;
169 	struct list_head		a_list;
170 	struct nvmet_fc_tgt_queue 	*queues[NVMET_NR_QUEUES + 1];
171 	struct kref			ref;
172 	struct work_struct		del_work;
173 };
174 
175 
176 static inline int
177 nvmet_fc_iodnum(struct nvmet_fc_ls_iod *iodptr)
178 {
179 	return (iodptr - iodptr->tgtport->iod);
180 }
181 
182 static inline int
183 nvmet_fc_fodnum(struct nvmet_fc_fcp_iod *fodptr)
184 {
185 	return (fodptr - fodptr->queue->fod);
186 }
187 
188 
189 /*
190  * Association and Connection IDs:
191  *
192  * Association ID will have random number in upper 6 bytes and zero
193  *   in lower 2 bytes
194  *
195  * Connection IDs will be Association ID with QID or'd in lower 2 bytes
196  *
197  * note: Association ID = Connection ID for queue 0
198  */
199 #define BYTES_FOR_QID			sizeof(u16)
200 #define BYTES_FOR_QID_SHIFT		(BYTES_FOR_QID * 8)
201 #define NVMET_FC_QUEUEID_MASK		((u64)((1 << BYTES_FOR_QID_SHIFT) - 1))
202 
203 static inline u64
204 nvmet_fc_makeconnid(struct nvmet_fc_tgt_assoc *assoc, u16 qid)
205 {
206 	return (assoc->association_id | qid);
207 }
208 
209 static inline u64
210 nvmet_fc_getassociationid(u64 connectionid)
211 {
212 	return connectionid & ~NVMET_FC_QUEUEID_MASK;
213 }
214 
215 static inline u16
216 nvmet_fc_getqueueid(u64 connectionid)
217 {
218 	return (u16)(connectionid & NVMET_FC_QUEUEID_MASK);
219 }
220 
221 static inline struct nvmet_fc_tgtport *
222 targetport_to_tgtport(struct nvmet_fc_target_port *targetport)
223 {
224 	return container_of(targetport, struct nvmet_fc_tgtport,
225 				 fc_target_port);
226 }
227 
228 static inline struct nvmet_fc_fcp_iod *
229 nvmet_req_to_fod(struct nvmet_req *nvme_req)
230 {
231 	return container_of(nvme_req, struct nvmet_fc_fcp_iod, req);
232 }
233 
234 
235 /* *************************** Globals **************************** */
236 
237 
238 static DEFINE_SPINLOCK(nvmet_fc_tgtlock);
239 
240 static LIST_HEAD(nvmet_fc_target_list);
241 static DEFINE_IDA(nvmet_fc_tgtport_cnt);
242 static LIST_HEAD(nvmet_fc_portentry_list);
243 
244 
245 static void nvmet_fc_handle_ls_rqst_work(struct work_struct *work);
246 static void nvmet_fc_fcp_rqst_op_defer_work(struct work_struct *work);
247 static void nvmet_fc_tgt_a_put(struct nvmet_fc_tgt_assoc *assoc);
248 static int nvmet_fc_tgt_a_get(struct nvmet_fc_tgt_assoc *assoc);
249 static void nvmet_fc_tgt_q_put(struct nvmet_fc_tgt_queue *queue);
250 static int nvmet_fc_tgt_q_get(struct nvmet_fc_tgt_queue *queue);
251 static void nvmet_fc_tgtport_put(struct nvmet_fc_tgtport *tgtport);
252 static void nvmet_fc_put_tgtport_work(struct work_struct *work)
253 {
254 	struct nvmet_fc_tgtport *tgtport =
255 		container_of(work, struct nvmet_fc_tgtport, put_work);
256 
257 	nvmet_fc_tgtport_put(tgtport);
258 }
259 static int nvmet_fc_tgtport_get(struct nvmet_fc_tgtport *tgtport);
260 static void nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
261 					struct nvmet_fc_fcp_iod *fod);
262 static void nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc);
263 static void nvmet_fc_xmt_ls_rsp(struct nvmet_fc_tgtport *tgtport,
264 				struct nvmet_fc_ls_iod *iod);
265 
266 
267 /* *********************** FC-NVME DMA Handling **************************** */
268 
269 /*
270  * The fcloop device passes in a NULL device pointer. Real LLD's will
271  * pass in a valid device pointer. If NULL is passed to the dma mapping
272  * routines, depending on the platform, it may or may not succeed, and
273  * may crash.
274  *
275  * As such:
276  * Wrapper all the dma routines and check the dev pointer.
277  *
278  * If simple mappings (return just a dma address, we'll noop them,
279  * returning a dma address of 0.
280  *
281  * On more complex mappings (dma_map_sg), a pseudo routine fills
282  * in the scatter list, setting all dma addresses to 0.
283  */
284 
285 static inline dma_addr_t
286 fc_dma_map_single(struct device *dev, void *ptr, size_t size,
287 		enum dma_data_direction dir)
288 {
289 	return dev ? dma_map_single(dev, ptr, size, dir) : (dma_addr_t)0L;
290 }
291 
292 static inline int
293 fc_dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
294 {
295 	return dev ? dma_mapping_error(dev, dma_addr) : 0;
296 }
297 
298 static inline void
299 fc_dma_unmap_single(struct device *dev, dma_addr_t addr, size_t size,
300 	enum dma_data_direction dir)
301 {
302 	if (dev)
303 		dma_unmap_single(dev, addr, size, dir);
304 }
305 
306 static inline void
307 fc_dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
308 		enum dma_data_direction dir)
309 {
310 	if (dev)
311 		dma_sync_single_for_cpu(dev, addr, size, dir);
312 }
313 
314 static inline void
315 fc_dma_sync_single_for_device(struct device *dev, dma_addr_t addr, size_t size,
316 		enum dma_data_direction dir)
317 {
318 	if (dev)
319 		dma_sync_single_for_device(dev, addr, size, dir);
320 }
321 
322 /* pseudo dma_map_sg call */
323 static int
324 fc_map_sg(struct scatterlist *sg, int nents)
325 {
326 	struct scatterlist *s;
327 	int i;
328 
329 	WARN_ON(nents == 0 || sg[0].length == 0);
330 
331 	for_each_sg(sg, s, nents, i) {
332 		s->dma_address = 0L;
333 #ifdef CONFIG_NEED_SG_DMA_LENGTH
334 		s->dma_length = s->length;
335 #endif
336 	}
337 	return nents;
338 }
339 
340 static inline int
341 fc_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
342 		enum dma_data_direction dir)
343 {
344 	return dev ? dma_map_sg(dev, sg, nents, dir) : fc_map_sg(sg, nents);
345 }
346 
347 static inline void
348 fc_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
349 		enum dma_data_direction dir)
350 {
351 	if (dev)
352 		dma_unmap_sg(dev, sg, nents, dir);
353 }
354 
355 
356 /* ********************** FC-NVME LS XMT Handling ************************* */
357 
358 
359 static void
360 __nvmet_fc_finish_ls_req(struct nvmet_fc_ls_req_op *lsop)
361 {
362 	struct nvmet_fc_tgtport *tgtport = lsop->tgtport;
363 	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
364 	unsigned long flags;
365 
366 	spin_lock_irqsave(&tgtport->lock, flags);
367 
368 	if (!lsop->req_queued) {
369 		spin_unlock_irqrestore(&tgtport->lock, flags);
370 		goto out_putwork;
371 	}
372 
373 	list_del(&lsop->lsreq_list);
374 
375 	lsop->req_queued = false;
376 
377 	spin_unlock_irqrestore(&tgtport->lock, flags);
378 
379 	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
380 				  (lsreq->rqstlen + lsreq->rsplen),
381 				  DMA_BIDIRECTIONAL);
382 
383 out_putwork:
384 	queue_work(nvmet_wq, &tgtport->put_work);
385 }
386 
387 static int
388 __nvmet_fc_send_ls_req(struct nvmet_fc_tgtport *tgtport,
389 		struct nvmet_fc_ls_req_op *lsop,
390 		void (*done)(struct nvmefc_ls_req *req, int status))
391 {
392 	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
393 	unsigned long flags;
394 	int ret = 0;
395 
396 	if (!tgtport->ops->ls_req)
397 		return -EOPNOTSUPP;
398 
399 	if (!nvmet_fc_tgtport_get(tgtport))
400 		return -ESHUTDOWN;
401 
402 	lsreq->done = done;
403 	lsop->req_queued = false;
404 	INIT_LIST_HEAD(&lsop->lsreq_list);
405 
406 	lsreq->rqstdma = fc_dma_map_single(tgtport->dev, lsreq->rqstaddr,
407 				  lsreq->rqstlen + lsreq->rsplen,
408 				  DMA_BIDIRECTIONAL);
409 	if (fc_dma_mapping_error(tgtport->dev, lsreq->rqstdma)) {
410 		ret = -EFAULT;
411 		goto out_puttgtport;
412 	}
413 	lsreq->rspdma = lsreq->rqstdma + lsreq->rqstlen;
414 
415 	spin_lock_irqsave(&tgtport->lock, flags);
416 
417 	list_add_tail(&lsop->lsreq_list, &tgtport->ls_req_list);
418 
419 	lsop->req_queued = true;
420 
421 	spin_unlock_irqrestore(&tgtport->lock, flags);
422 
423 	ret = tgtport->ops->ls_req(&tgtport->fc_target_port, lsop->hosthandle,
424 				   lsreq);
425 	if (ret)
426 		goto out_unlink;
427 
428 	return 0;
429 
430 out_unlink:
431 	lsop->ls_error = ret;
432 	spin_lock_irqsave(&tgtport->lock, flags);
433 	lsop->req_queued = false;
434 	list_del(&lsop->lsreq_list);
435 	spin_unlock_irqrestore(&tgtport->lock, flags);
436 	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
437 				  (lsreq->rqstlen + lsreq->rsplen),
438 				  DMA_BIDIRECTIONAL);
439 out_puttgtport:
440 	nvmet_fc_tgtport_put(tgtport);
441 
442 	return ret;
443 }
444 
445 static int
446 nvmet_fc_send_ls_req_async(struct nvmet_fc_tgtport *tgtport,
447 		struct nvmet_fc_ls_req_op *lsop,
448 		void (*done)(struct nvmefc_ls_req *req, int status))
449 {
450 	/* don't wait for completion */
451 
452 	return __nvmet_fc_send_ls_req(tgtport, lsop, done);
453 }
454 
455 static void
456 nvmet_fc_disconnect_assoc_done(struct nvmefc_ls_req *lsreq, int status)
457 {
458 	struct nvmet_fc_ls_req_op *lsop =
459 		container_of(lsreq, struct nvmet_fc_ls_req_op, ls_req);
460 
461 	__nvmet_fc_finish_ls_req(lsop);
462 
463 	/* fc-nvme target doesn't care about success or failure of cmd */
464 
465 	kfree(lsop);
466 }
467 
468 /*
469  * This routine sends a FC-NVME LS to disconnect (aka terminate)
470  * the FC-NVME Association.  Terminating the association also
471  * terminates the FC-NVME connections (per queue, both admin and io
472  * queues) that are part of the association. E.g. things are torn
473  * down, and the related FC-NVME Association ID and Connection IDs
474  * become invalid.
475  *
476  * The behavior of the fc-nvme target is such that it's
477  * understanding of the association and connections will implicitly
478  * be torn down. The action is implicit as it may be due to a loss of
479  * connectivity with the fc-nvme host, so the target may never get a
480  * response even if it tried.  As such, the action of this routine
481  * is to asynchronously send the LS, ignore any results of the LS, and
482  * continue on with terminating the association. If the fc-nvme host
483  * is present and receives the LS, it too can tear down.
484  */
485 static void
486 nvmet_fc_xmt_disconnect_assoc(struct nvmet_fc_tgt_assoc *assoc)
487 {
488 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
489 	struct fcnvme_ls_disconnect_assoc_rqst *discon_rqst;
490 	struct fcnvme_ls_disconnect_assoc_acc *discon_acc;
491 	struct nvmet_fc_ls_req_op *lsop;
492 	struct nvmefc_ls_req *lsreq;
493 	int ret;
494 
495 	/*
496 	 * If ls_req is NULL or no hosthandle, it's an older lldd and no
497 	 * message is normal. Otherwise, send unless the hostport has
498 	 * already been invalidated by the lldd.
499 	 */
500 	if (!tgtport->ops->ls_req || assoc->hostport->invalid)
501 		return;
502 
503 	lsop = kzalloc((sizeof(*lsop) +
504 			sizeof(*discon_rqst) + sizeof(*discon_acc) +
505 			tgtport->ops->lsrqst_priv_sz), GFP_KERNEL);
506 	if (!lsop) {
507 		dev_info(tgtport->dev,
508 			"{%d:%d} send Disconnect Association failed: ENOMEM\n",
509 			tgtport->fc_target_port.port_num, assoc->a_id);
510 		return;
511 	}
512 
513 	discon_rqst = (struct fcnvme_ls_disconnect_assoc_rqst *)&lsop[1];
514 	discon_acc = (struct fcnvme_ls_disconnect_assoc_acc *)&discon_rqst[1];
515 	lsreq = &lsop->ls_req;
516 	if (tgtport->ops->lsrqst_priv_sz)
517 		lsreq->private = (void *)&discon_acc[1];
518 	else
519 		lsreq->private = NULL;
520 
521 	lsop->tgtport = tgtport;
522 	lsop->hosthandle = assoc->hostport->hosthandle;
523 
524 	nvmefc_fmt_lsreq_discon_assoc(lsreq, discon_rqst, discon_acc,
525 				assoc->association_id);
526 
527 	ret = nvmet_fc_send_ls_req_async(tgtport, lsop,
528 				nvmet_fc_disconnect_assoc_done);
529 	if (ret) {
530 		dev_info(tgtport->dev,
531 			"{%d:%d} XMT Disconnect Association failed: %d\n",
532 			tgtport->fc_target_port.port_num, assoc->a_id, ret);
533 		kfree(lsop);
534 	}
535 }
536 
537 
538 /* *********************** FC-NVME Port Management ************************ */
539 
540 
541 static int
542 nvmet_fc_alloc_ls_iodlist(struct nvmet_fc_tgtport *tgtport)
543 {
544 	struct nvmet_fc_ls_iod *iod;
545 	int i;
546 
547 	iod = kcalloc(NVMET_LS_CTX_COUNT, sizeof(struct nvmet_fc_ls_iod),
548 			GFP_KERNEL);
549 	if (!iod)
550 		return -ENOMEM;
551 
552 	tgtport->iod = iod;
553 
554 	for (i = 0; i < NVMET_LS_CTX_COUNT; iod++, i++) {
555 		INIT_WORK(&iod->work, nvmet_fc_handle_ls_rqst_work);
556 		iod->tgtport = tgtport;
557 		list_add_tail(&iod->ls_rcv_list, &tgtport->ls_rcv_list);
558 
559 		iod->rqstbuf = kzalloc(sizeof(union nvmefc_ls_requests) +
560 				       sizeof(union nvmefc_ls_responses),
561 				       GFP_KERNEL);
562 		if (!iod->rqstbuf)
563 			goto out_fail;
564 
565 		iod->rspbuf = (union nvmefc_ls_responses *)&iod->rqstbuf[1];
566 
567 		iod->rspdma = fc_dma_map_single(tgtport->dev, iod->rspbuf,
568 						sizeof(*iod->rspbuf),
569 						DMA_TO_DEVICE);
570 		if (fc_dma_mapping_error(tgtport->dev, iod->rspdma))
571 			goto out_fail;
572 	}
573 
574 	return 0;
575 
576 out_fail:
577 	kfree(iod->rqstbuf);
578 	list_del(&iod->ls_rcv_list);
579 	for (iod--, i--; i >= 0; iod--, i--) {
580 		fc_dma_unmap_single(tgtport->dev, iod->rspdma,
581 				sizeof(*iod->rspbuf), DMA_TO_DEVICE);
582 		kfree(iod->rqstbuf);
583 		list_del(&iod->ls_rcv_list);
584 	}
585 
586 	kfree(iod);
587 
588 	return -EFAULT;
589 }
590 
591 static void
592 nvmet_fc_free_ls_iodlist(struct nvmet_fc_tgtport *tgtport)
593 {
594 	struct nvmet_fc_ls_iod *iod = tgtport->iod;
595 	int i;
596 
597 	for (i = 0; i < NVMET_LS_CTX_COUNT; iod++, i++) {
598 		fc_dma_unmap_single(tgtport->dev,
599 				iod->rspdma, sizeof(*iod->rspbuf),
600 				DMA_TO_DEVICE);
601 		kfree(iod->rqstbuf);
602 		list_del(&iod->ls_rcv_list);
603 	}
604 	kfree(tgtport->iod);
605 }
606 
607 static struct nvmet_fc_ls_iod *
608 nvmet_fc_alloc_ls_iod(struct nvmet_fc_tgtport *tgtport)
609 {
610 	struct nvmet_fc_ls_iod *iod;
611 	unsigned long flags;
612 
613 	spin_lock_irqsave(&tgtport->lock, flags);
614 	iod = list_first_entry_or_null(&tgtport->ls_rcv_list,
615 					struct nvmet_fc_ls_iod, ls_rcv_list);
616 	if (iod)
617 		list_move_tail(&iod->ls_rcv_list, &tgtport->ls_busylist);
618 	spin_unlock_irqrestore(&tgtport->lock, flags);
619 	return iod;
620 }
621 
622 
623 static void
624 nvmet_fc_free_ls_iod(struct nvmet_fc_tgtport *tgtport,
625 			struct nvmet_fc_ls_iod *iod)
626 {
627 	unsigned long flags;
628 
629 	spin_lock_irqsave(&tgtport->lock, flags);
630 	list_move(&iod->ls_rcv_list, &tgtport->ls_rcv_list);
631 	spin_unlock_irqrestore(&tgtport->lock, flags);
632 }
633 
634 static void
635 nvmet_fc_prep_fcp_iodlist(struct nvmet_fc_tgtport *tgtport,
636 				struct nvmet_fc_tgt_queue *queue)
637 {
638 	struct nvmet_fc_fcp_iod *fod = queue->fod;
639 	int i;
640 
641 	for (i = 0; i < queue->sqsize; fod++, i++) {
642 		INIT_WORK(&fod->defer_work, nvmet_fc_fcp_rqst_op_defer_work);
643 		fod->tgtport = tgtport;
644 		fod->queue = queue;
645 		fod->active = false;
646 		fod->abort = false;
647 		fod->aborted = false;
648 		fod->fcpreq = NULL;
649 		list_add_tail(&fod->fcp_list, &queue->fod_list);
650 		spin_lock_init(&fod->flock);
651 
652 		fod->rspdma = fc_dma_map_single(tgtport->dev, &fod->rspiubuf,
653 					sizeof(fod->rspiubuf), DMA_TO_DEVICE);
654 		if (fc_dma_mapping_error(tgtport->dev, fod->rspdma)) {
655 			list_del(&fod->fcp_list);
656 			for (fod--, i--; i >= 0; fod--, i--) {
657 				fc_dma_unmap_single(tgtport->dev, fod->rspdma,
658 						sizeof(fod->rspiubuf),
659 						DMA_TO_DEVICE);
660 				fod->rspdma = 0L;
661 				list_del(&fod->fcp_list);
662 			}
663 
664 			return;
665 		}
666 	}
667 }
668 
669 static void
670 nvmet_fc_destroy_fcp_iodlist(struct nvmet_fc_tgtport *tgtport,
671 				struct nvmet_fc_tgt_queue *queue)
672 {
673 	struct nvmet_fc_fcp_iod *fod = queue->fod;
674 	int i;
675 
676 	for (i = 0; i < queue->sqsize; fod++, i++) {
677 		if (fod->rspdma)
678 			fc_dma_unmap_single(tgtport->dev, fod->rspdma,
679 				sizeof(fod->rspiubuf), DMA_TO_DEVICE);
680 	}
681 }
682 
683 static struct nvmet_fc_fcp_iod *
684 nvmet_fc_alloc_fcp_iod(struct nvmet_fc_tgt_queue *queue)
685 {
686 	struct nvmet_fc_fcp_iod *fod;
687 
688 	lockdep_assert_held(&queue->qlock);
689 
690 	fod = list_first_entry_or_null(&queue->fod_list,
691 					struct nvmet_fc_fcp_iod, fcp_list);
692 	if (fod) {
693 		list_del(&fod->fcp_list);
694 		fod->active = true;
695 		/*
696 		 * no queue reference is taken, as it was taken by the
697 		 * queue lookup just prior to the allocation. The iod
698 		 * will "inherit" that reference.
699 		 */
700 	}
701 	return fod;
702 }
703 
704 
705 static void
706 nvmet_fc_queue_fcp_req(struct nvmet_fc_tgtport *tgtport,
707 		       struct nvmet_fc_tgt_queue *queue,
708 		       struct nvmefc_tgt_fcp_req *fcpreq)
709 {
710 	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
711 
712 	/*
713 	 * put all admin cmds on hw queue id 0. All io commands go to
714 	 * the respective hw queue based on a modulo basis
715 	 */
716 	fcpreq->hwqid = queue->qid ?
717 			((queue->qid - 1) % tgtport->ops->max_hw_queues) : 0;
718 
719 	nvmet_fc_handle_fcp_rqst(tgtport, fod);
720 }
721 
722 static void
723 nvmet_fc_fcp_rqst_op_defer_work(struct work_struct *work)
724 {
725 	struct nvmet_fc_fcp_iod *fod =
726 		container_of(work, struct nvmet_fc_fcp_iod, defer_work);
727 
728 	/* Submit deferred IO for processing */
729 	nvmet_fc_queue_fcp_req(fod->tgtport, fod->queue, fod->fcpreq);
730 
731 }
732 
733 static void
734 nvmet_fc_free_fcp_iod(struct nvmet_fc_tgt_queue *queue,
735 			struct nvmet_fc_fcp_iod *fod)
736 {
737 	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
738 	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
739 	struct nvmet_fc_defer_fcp_req *deferfcp;
740 	unsigned long flags;
741 
742 	fc_dma_sync_single_for_cpu(tgtport->dev, fod->rspdma,
743 				sizeof(fod->rspiubuf), DMA_TO_DEVICE);
744 
745 	fcpreq->nvmet_fc_private = NULL;
746 
747 	fod->active = false;
748 	fod->abort = false;
749 	fod->aborted = false;
750 	fod->writedataactive = false;
751 	fod->fcpreq = NULL;
752 
753 	tgtport->ops->fcp_req_release(&tgtport->fc_target_port, fcpreq);
754 
755 	/* release the queue lookup reference on the completed IO */
756 	nvmet_fc_tgt_q_put(queue);
757 
758 	spin_lock_irqsave(&queue->qlock, flags);
759 	deferfcp = list_first_entry_or_null(&queue->pending_cmd_list,
760 				struct nvmet_fc_defer_fcp_req, req_list);
761 	if (!deferfcp) {
762 		list_add_tail(&fod->fcp_list, &fod->queue->fod_list);
763 		spin_unlock_irqrestore(&queue->qlock, flags);
764 		return;
765 	}
766 
767 	/* Re-use the fod for the next pending cmd that was deferred */
768 	list_del(&deferfcp->req_list);
769 
770 	fcpreq = deferfcp->fcp_req;
771 
772 	/* deferfcp can be reused for another IO at a later date */
773 	list_add_tail(&deferfcp->req_list, &queue->avail_defer_list);
774 
775 	spin_unlock_irqrestore(&queue->qlock, flags);
776 
777 	/* Save NVME CMD IO in fod */
778 	memcpy(&fod->cmdiubuf, fcpreq->rspaddr, fcpreq->rsplen);
779 
780 	/* Setup new fcpreq to be processed */
781 	fcpreq->rspaddr = NULL;
782 	fcpreq->rsplen  = 0;
783 	fcpreq->nvmet_fc_private = fod;
784 	fod->fcpreq = fcpreq;
785 	fod->active = true;
786 
787 	/* inform LLDD IO is now being processed */
788 	tgtport->ops->defer_rcv(&tgtport->fc_target_port, fcpreq);
789 
790 	/*
791 	 * Leave the queue lookup get reference taken when
792 	 * fod was originally allocated.
793 	 */
794 
795 	queue_work(queue->work_q, &fod->defer_work);
796 }
797 
798 static struct nvmet_fc_tgt_queue *
799 nvmet_fc_alloc_target_queue(struct nvmet_fc_tgt_assoc *assoc,
800 			u16 qid, u16 sqsize)
801 {
802 	struct nvmet_fc_tgt_queue *queue;
803 	int ret;
804 
805 	if (qid > NVMET_NR_QUEUES)
806 		return NULL;
807 
808 	queue = kzalloc(struct_size(queue, fod, sqsize), GFP_KERNEL);
809 	if (!queue)
810 		return NULL;
811 
812 	queue->work_q = alloc_workqueue("ntfc%d.%d.%d", 0, 0,
813 				assoc->tgtport->fc_target_port.port_num,
814 				assoc->a_id, qid);
815 	if (!queue->work_q)
816 		goto out_free_queue;
817 
818 	queue->qid = qid;
819 	queue->sqsize = sqsize;
820 	queue->assoc = assoc;
821 	INIT_LIST_HEAD(&queue->fod_list);
822 	INIT_LIST_HEAD(&queue->avail_defer_list);
823 	INIT_LIST_HEAD(&queue->pending_cmd_list);
824 	atomic_set(&queue->connected, 0);
825 	atomic_set(&queue->sqtail, 0);
826 	atomic_set(&queue->rsn, 1);
827 	atomic_set(&queue->zrspcnt, 0);
828 	spin_lock_init(&queue->qlock);
829 	kref_init(&queue->ref);
830 
831 	nvmet_fc_prep_fcp_iodlist(assoc->tgtport, queue);
832 
833 	ret = nvmet_sq_init(&queue->nvme_sq);
834 	if (ret)
835 		goto out_fail_iodlist;
836 
837 	WARN_ON(assoc->queues[qid]);
838 	assoc->queues[qid] = queue;
839 
840 	return queue;
841 
842 out_fail_iodlist:
843 	nvmet_fc_destroy_fcp_iodlist(assoc->tgtport, queue);
844 	destroy_workqueue(queue->work_q);
845 out_free_queue:
846 	kfree(queue);
847 	return NULL;
848 }
849 
850 
851 static void
852 nvmet_fc_tgt_queue_free(struct kref *ref)
853 {
854 	struct nvmet_fc_tgt_queue *queue =
855 		container_of(ref, struct nvmet_fc_tgt_queue, ref);
856 
857 	nvmet_fc_destroy_fcp_iodlist(queue->assoc->tgtport, queue);
858 
859 	destroy_workqueue(queue->work_q);
860 
861 	kfree(queue);
862 }
863 
864 static void
865 nvmet_fc_tgt_q_put(struct nvmet_fc_tgt_queue *queue)
866 {
867 	kref_put(&queue->ref, nvmet_fc_tgt_queue_free);
868 }
869 
870 static int
871 nvmet_fc_tgt_q_get(struct nvmet_fc_tgt_queue *queue)
872 {
873 	return kref_get_unless_zero(&queue->ref);
874 }
875 
876 
877 static void
878 nvmet_fc_delete_target_queue(struct nvmet_fc_tgt_queue *queue)
879 {
880 	struct nvmet_fc_tgtport *tgtport = queue->assoc->tgtport;
881 	struct nvmet_fc_fcp_iod *fod = queue->fod;
882 	struct nvmet_fc_defer_fcp_req *deferfcp, *tempptr;
883 	unsigned long flags;
884 	int i;
885 	bool disconnect;
886 
887 	disconnect = atomic_xchg(&queue->connected, 0);
888 
889 	/* if not connected, nothing to do */
890 	if (!disconnect)
891 		return;
892 
893 	spin_lock_irqsave(&queue->qlock, flags);
894 	/* abort outstanding io's */
895 	for (i = 0; i < queue->sqsize; fod++, i++) {
896 		if (fod->active) {
897 			spin_lock(&fod->flock);
898 			fod->abort = true;
899 			/*
900 			 * only call lldd abort routine if waiting for
901 			 * writedata. other outstanding ops should finish
902 			 * on their own.
903 			 */
904 			if (fod->writedataactive) {
905 				fod->aborted = true;
906 				spin_unlock(&fod->flock);
907 				tgtport->ops->fcp_abort(
908 					&tgtport->fc_target_port, fod->fcpreq);
909 			} else
910 				spin_unlock(&fod->flock);
911 		}
912 	}
913 
914 	/* Cleanup defer'ed IOs in queue */
915 	list_for_each_entry_safe(deferfcp, tempptr, &queue->avail_defer_list,
916 				req_list) {
917 		list_del(&deferfcp->req_list);
918 		kfree(deferfcp);
919 	}
920 
921 	for (;;) {
922 		deferfcp = list_first_entry_or_null(&queue->pending_cmd_list,
923 				struct nvmet_fc_defer_fcp_req, req_list);
924 		if (!deferfcp)
925 			break;
926 
927 		list_del(&deferfcp->req_list);
928 		spin_unlock_irqrestore(&queue->qlock, flags);
929 
930 		tgtport->ops->defer_rcv(&tgtport->fc_target_port,
931 				deferfcp->fcp_req);
932 
933 		tgtport->ops->fcp_abort(&tgtport->fc_target_port,
934 				deferfcp->fcp_req);
935 
936 		tgtport->ops->fcp_req_release(&tgtport->fc_target_port,
937 				deferfcp->fcp_req);
938 
939 		/* release the queue lookup reference */
940 		nvmet_fc_tgt_q_put(queue);
941 
942 		kfree(deferfcp);
943 
944 		spin_lock_irqsave(&queue->qlock, flags);
945 	}
946 	spin_unlock_irqrestore(&queue->qlock, flags);
947 
948 	flush_workqueue(queue->work_q);
949 
950 	nvmet_sq_destroy(&queue->nvme_sq);
951 
952 	nvmet_fc_tgt_q_put(queue);
953 }
954 
955 static struct nvmet_fc_tgt_queue *
956 nvmet_fc_find_target_queue(struct nvmet_fc_tgtport *tgtport,
957 				u64 connection_id)
958 {
959 	struct nvmet_fc_tgt_assoc *assoc;
960 	struct nvmet_fc_tgt_queue *queue;
961 	u64 association_id = nvmet_fc_getassociationid(connection_id);
962 	u16 qid = nvmet_fc_getqueueid(connection_id);
963 
964 	if (qid > NVMET_NR_QUEUES)
965 		return NULL;
966 
967 	rcu_read_lock();
968 	list_for_each_entry_rcu(assoc, &tgtport->assoc_list, a_list) {
969 		if (association_id == assoc->association_id) {
970 			queue = assoc->queues[qid];
971 			if (queue &&
972 			    (!atomic_read(&queue->connected) ||
973 			     !nvmet_fc_tgt_q_get(queue)))
974 				queue = NULL;
975 			rcu_read_unlock();
976 			return queue;
977 		}
978 	}
979 	rcu_read_unlock();
980 	return NULL;
981 }
982 
983 static void
984 nvmet_fc_hostport_free(struct kref *ref)
985 {
986 	struct nvmet_fc_hostport *hostport =
987 		container_of(ref, struct nvmet_fc_hostport, ref);
988 	struct nvmet_fc_tgtport *tgtport = hostport->tgtport;
989 	unsigned long flags;
990 
991 	spin_lock_irqsave(&tgtport->lock, flags);
992 	list_del(&hostport->host_list);
993 	spin_unlock_irqrestore(&tgtport->lock, flags);
994 	if (tgtport->ops->host_release && hostport->invalid)
995 		tgtport->ops->host_release(hostport->hosthandle);
996 	kfree(hostport);
997 	nvmet_fc_tgtport_put(tgtport);
998 }
999 
1000 static void
1001 nvmet_fc_hostport_put(struct nvmet_fc_hostport *hostport)
1002 {
1003 	kref_put(&hostport->ref, nvmet_fc_hostport_free);
1004 }
1005 
1006 static int
1007 nvmet_fc_hostport_get(struct nvmet_fc_hostport *hostport)
1008 {
1009 	return kref_get_unless_zero(&hostport->ref);
1010 }
1011 
1012 static void
1013 nvmet_fc_free_hostport(struct nvmet_fc_hostport *hostport)
1014 {
1015 	/* if LLDD not implemented, leave as NULL */
1016 	if (!hostport || !hostport->hosthandle)
1017 		return;
1018 
1019 	nvmet_fc_hostport_put(hostport);
1020 }
1021 
1022 static struct nvmet_fc_hostport *
1023 nvmet_fc_match_hostport(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
1024 {
1025 	struct nvmet_fc_hostport *host;
1026 
1027 	lockdep_assert_held(&tgtport->lock);
1028 
1029 	list_for_each_entry(host, &tgtport->host_list, host_list) {
1030 		if (host->hosthandle == hosthandle && !host->invalid) {
1031 			if (nvmet_fc_hostport_get(host))
1032 				return host;
1033 		}
1034 	}
1035 
1036 	return NULL;
1037 }
1038 
1039 static struct nvmet_fc_hostport *
1040 nvmet_fc_alloc_hostport(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
1041 {
1042 	struct nvmet_fc_hostport *newhost, *match = NULL;
1043 	unsigned long flags;
1044 
1045 	/* if LLDD not implemented, leave as NULL */
1046 	if (!hosthandle)
1047 		return NULL;
1048 
1049 	/*
1050 	 * take reference for what will be the newly allocated hostport if
1051 	 * we end up using a new allocation
1052 	 */
1053 	if (!nvmet_fc_tgtport_get(tgtport))
1054 		return ERR_PTR(-EINVAL);
1055 
1056 	spin_lock_irqsave(&tgtport->lock, flags);
1057 	match = nvmet_fc_match_hostport(tgtport, hosthandle);
1058 	spin_unlock_irqrestore(&tgtport->lock, flags);
1059 
1060 	if (match) {
1061 		/* no new allocation - release reference */
1062 		nvmet_fc_tgtport_put(tgtport);
1063 		return match;
1064 	}
1065 
1066 	newhost = kzalloc(sizeof(*newhost), GFP_KERNEL);
1067 	if (!newhost) {
1068 		/* no new allocation - release reference */
1069 		nvmet_fc_tgtport_put(tgtport);
1070 		return ERR_PTR(-ENOMEM);
1071 	}
1072 
1073 	spin_lock_irqsave(&tgtport->lock, flags);
1074 	match = nvmet_fc_match_hostport(tgtport, hosthandle);
1075 	if (match) {
1076 		/* new allocation not needed */
1077 		kfree(newhost);
1078 		newhost = match;
1079 	} else {
1080 		newhost->tgtport = tgtport;
1081 		newhost->hosthandle = hosthandle;
1082 		INIT_LIST_HEAD(&newhost->host_list);
1083 		kref_init(&newhost->ref);
1084 
1085 		list_add_tail(&newhost->host_list, &tgtport->host_list);
1086 	}
1087 	spin_unlock_irqrestore(&tgtport->lock, flags);
1088 
1089 	return newhost;
1090 }
1091 
1092 static void
1093 nvmet_fc_delete_assoc(struct nvmet_fc_tgt_assoc *assoc)
1094 {
1095 	nvmet_fc_delete_target_assoc(assoc);
1096 	nvmet_fc_tgt_a_put(assoc);
1097 }
1098 
1099 static void
1100 nvmet_fc_delete_assoc_work(struct work_struct *work)
1101 {
1102 	struct nvmet_fc_tgt_assoc *assoc =
1103 		container_of(work, struct nvmet_fc_tgt_assoc, del_work);
1104 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
1105 
1106 	nvmet_fc_delete_assoc(assoc);
1107 	nvmet_fc_tgtport_put(tgtport);
1108 }
1109 
1110 static void
1111 nvmet_fc_schedule_delete_assoc(struct nvmet_fc_tgt_assoc *assoc)
1112 {
1113 	nvmet_fc_tgtport_get(assoc->tgtport);
1114 	queue_work(nvmet_wq, &assoc->del_work);
1115 }
1116 
1117 static bool
1118 nvmet_fc_assoc_exits(struct nvmet_fc_tgtport *tgtport, u64 association_id)
1119 {
1120 	struct nvmet_fc_tgt_assoc *a;
1121 
1122 	list_for_each_entry_rcu(a, &tgtport->assoc_list, a_list) {
1123 		if (association_id == a->association_id)
1124 			return true;
1125 	}
1126 
1127 	return false;
1128 }
1129 
1130 static struct nvmet_fc_tgt_assoc *
1131 nvmet_fc_alloc_target_assoc(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
1132 {
1133 	struct nvmet_fc_tgt_assoc *assoc;
1134 	unsigned long flags;
1135 	bool done;
1136 	u64 ran;
1137 	int idx;
1138 
1139 	if (!tgtport->pe)
1140 		return NULL;
1141 
1142 	assoc = kzalloc(sizeof(*assoc), GFP_KERNEL);
1143 	if (!assoc)
1144 		return NULL;
1145 
1146 	idx = ida_alloc(&tgtport->assoc_cnt, GFP_KERNEL);
1147 	if (idx < 0)
1148 		goto out_free_assoc;
1149 
1150 	assoc->hostport = nvmet_fc_alloc_hostport(tgtport, hosthandle);
1151 	if (IS_ERR(assoc->hostport))
1152 		goto out_ida;
1153 
1154 	assoc->tgtport = tgtport;
1155 	assoc->a_id = idx;
1156 	INIT_LIST_HEAD(&assoc->a_list);
1157 	kref_init(&assoc->ref);
1158 	INIT_WORK(&assoc->del_work, nvmet_fc_delete_assoc_work);
1159 	atomic_set(&assoc->terminating, 0);
1160 
1161 	done = false;
1162 	do {
1163 		get_random_bytes(&ran, sizeof(ran) - BYTES_FOR_QID);
1164 		ran = ran << BYTES_FOR_QID_SHIFT;
1165 
1166 		spin_lock_irqsave(&tgtport->lock, flags);
1167 		rcu_read_lock();
1168 		if (!nvmet_fc_assoc_exits(tgtport, ran)) {
1169 			assoc->association_id = ran;
1170 			list_add_tail_rcu(&assoc->a_list, &tgtport->assoc_list);
1171 			done = true;
1172 		}
1173 		rcu_read_unlock();
1174 		spin_unlock_irqrestore(&tgtport->lock, flags);
1175 	} while (!done);
1176 
1177 	return assoc;
1178 
1179 out_ida:
1180 	ida_free(&tgtport->assoc_cnt, idx);
1181 out_free_assoc:
1182 	kfree(assoc);
1183 	return NULL;
1184 }
1185 
1186 static void
1187 nvmet_fc_target_assoc_free(struct kref *ref)
1188 {
1189 	struct nvmet_fc_tgt_assoc *assoc =
1190 		container_of(ref, struct nvmet_fc_tgt_assoc, ref);
1191 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
1192 	struct nvmet_fc_ls_iod	*oldls;
1193 	unsigned long flags;
1194 	int i;
1195 
1196 	for (i = NVMET_NR_QUEUES; i >= 0; i--) {
1197 		if (assoc->queues[i])
1198 			nvmet_fc_delete_target_queue(assoc->queues[i]);
1199 	}
1200 
1201 	/* Send Disconnect now that all i/o has completed */
1202 	nvmet_fc_xmt_disconnect_assoc(assoc);
1203 
1204 	nvmet_fc_free_hostport(assoc->hostport);
1205 	spin_lock_irqsave(&tgtport->lock, flags);
1206 	oldls = assoc->rcv_disconn;
1207 	spin_unlock_irqrestore(&tgtport->lock, flags);
1208 	/* if pending Rcv Disconnect Association LS, send rsp now */
1209 	if (oldls)
1210 		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
1211 	ida_free(&tgtport->assoc_cnt, assoc->a_id);
1212 	dev_info(tgtport->dev,
1213 		"{%d:%d} Association freed\n",
1214 		tgtport->fc_target_port.port_num, assoc->a_id);
1215 	kfree(assoc);
1216 }
1217 
1218 static void
1219 nvmet_fc_tgt_a_put(struct nvmet_fc_tgt_assoc *assoc)
1220 {
1221 	kref_put(&assoc->ref, nvmet_fc_target_assoc_free);
1222 }
1223 
1224 static int
1225 nvmet_fc_tgt_a_get(struct nvmet_fc_tgt_assoc *assoc)
1226 {
1227 	return kref_get_unless_zero(&assoc->ref);
1228 }
1229 
1230 static void
1231 nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc)
1232 {
1233 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
1234 	unsigned long flags;
1235 	int i, terminating;
1236 
1237 	terminating = atomic_xchg(&assoc->terminating, 1);
1238 
1239 	/* if already terminating, do nothing */
1240 	if (terminating)
1241 		return;
1242 
1243 	spin_lock_irqsave(&tgtport->lock, flags);
1244 	list_del_rcu(&assoc->a_list);
1245 	spin_unlock_irqrestore(&tgtport->lock, flags);
1246 
1247 	synchronize_rcu();
1248 
1249 	/* ensure all in-flight I/Os have been processed */
1250 	for (i = NVMET_NR_QUEUES; i >= 0; i--) {
1251 		if (assoc->queues[i])
1252 			flush_workqueue(assoc->queues[i]->work_q);
1253 	}
1254 
1255 	dev_info(tgtport->dev,
1256 		"{%d:%d} Association deleted\n",
1257 		tgtport->fc_target_port.port_num, assoc->a_id);
1258 }
1259 
1260 static struct nvmet_fc_tgt_assoc *
1261 nvmet_fc_find_target_assoc(struct nvmet_fc_tgtport *tgtport,
1262 				u64 association_id)
1263 {
1264 	struct nvmet_fc_tgt_assoc *assoc;
1265 	struct nvmet_fc_tgt_assoc *ret = NULL;
1266 
1267 	rcu_read_lock();
1268 	list_for_each_entry_rcu(assoc, &tgtport->assoc_list, a_list) {
1269 		if (association_id == assoc->association_id) {
1270 			ret = assoc;
1271 			if (!nvmet_fc_tgt_a_get(assoc))
1272 				ret = NULL;
1273 			break;
1274 		}
1275 	}
1276 	rcu_read_unlock();
1277 
1278 	return ret;
1279 }
1280 
1281 static void
1282 nvmet_fc_portentry_bind(struct nvmet_fc_tgtport *tgtport,
1283 			struct nvmet_fc_port_entry *pe,
1284 			struct nvmet_port *port)
1285 {
1286 	lockdep_assert_held(&nvmet_fc_tgtlock);
1287 
1288 	pe->tgtport = tgtport;
1289 	tgtport->pe = pe;
1290 
1291 	pe->port = port;
1292 	port->priv = pe;
1293 
1294 	pe->node_name = tgtport->fc_target_port.node_name;
1295 	pe->port_name = tgtport->fc_target_port.port_name;
1296 	INIT_LIST_HEAD(&pe->pe_list);
1297 
1298 	list_add_tail(&pe->pe_list, &nvmet_fc_portentry_list);
1299 }
1300 
1301 static void
1302 nvmet_fc_portentry_unbind(struct nvmet_fc_port_entry *pe)
1303 {
1304 	unsigned long flags;
1305 
1306 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1307 	if (pe->tgtport)
1308 		pe->tgtport->pe = NULL;
1309 	list_del(&pe->pe_list);
1310 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1311 }
1312 
1313 /*
1314  * called when a targetport deregisters. Breaks the relationship
1315  * with the nvmet port, but leaves the port_entry in place so that
1316  * re-registration can resume operation.
1317  */
1318 static void
1319 nvmet_fc_portentry_unbind_tgt(struct nvmet_fc_tgtport *tgtport)
1320 {
1321 	struct nvmet_fc_port_entry *pe;
1322 	unsigned long flags;
1323 
1324 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1325 	pe = tgtport->pe;
1326 	if (pe)
1327 		pe->tgtport = NULL;
1328 	tgtport->pe = NULL;
1329 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1330 }
1331 
1332 /*
1333  * called when a new targetport is registered. Looks in the
1334  * existing nvmet port_entries to see if the nvmet layer is
1335  * configured for the targetport's wwn's. (the targetport existed,
1336  * nvmet configured, the lldd unregistered the tgtport, and is now
1337  * reregistering the same targetport).  If so, set the nvmet port
1338  * port entry on the targetport.
1339  */
1340 static void
1341 nvmet_fc_portentry_rebind_tgt(struct nvmet_fc_tgtport *tgtport)
1342 {
1343 	struct nvmet_fc_port_entry *pe;
1344 	unsigned long flags;
1345 
1346 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1347 	list_for_each_entry(pe, &nvmet_fc_portentry_list, pe_list) {
1348 		if (tgtport->fc_target_port.node_name == pe->node_name &&
1349 		    tgtport->fc_target_port.port_name == pe->port_name) {
1350 			WARN_ON(pe->tgtport);
1351 			tgtport->pe = pe;
1352 			pe->tgtport = tgtport;
1353 			break;
1354 		}
1355 	}
1356 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1357 }
1358 
1359 /**
1360  * nvmet_fc_register_targetport - transport entry point called by an
1361  *                              LLDD to register the existence of a local
1362  *                              NVME subystem FC port.
1363  * @pinfo:     pointer to information about the port to be registered
1364  * @template:  LLDD entrypoints and operational parameters for the port
1365  * @dev:       physical hardware device node port corresponds to. Will be
1366  *             used for DMA mappings
1367  * @portptr:   pointer to a local port pointer. Upon success, the routine
1368  *             will allocate a nvme_fc_local_port structure and place its
1369  *             address in the local port pointer. Upon failure, local port
1370  *             pointer will be set to NULL.
1371  *
1372  * Returns:
1373  * a completion status. Must be 0 upon success; a negative errno
1374  * (ex: -ENXIO) upon failure.
1375  */
1376 int
1377 nvmet_fc_register_targetport(struct nvmet_fc_port_info *pinfo,
1378 			struct nvmet_fc_target_template *template,
1379 			struct device *dev,
1380 			struct nvmet_fc_target_port **portptr)
1381 {
1382 	struct nvmet_fc_tgtport *newrec;
1383 	unsigned long flags;
1384 	int ret, idx;
1385 
1386 	if (!template->xmt_ls_rsp || !template->fcp_op ||
1387 	    !template->fcp_abort ||
1388 	    !template->fcp_req_release || !template->targetport_delete ||
1389 	    !template->max_hw_queues || !template->max_sgl_segments ||
1390 	    !template->max_dif_sgl_segments || !template->dma_boundary) {
1391 		ret = -EINVAL;
1392 		goto out_regtgt_failed;
1393 	}
1394 
1395 	newrec = kzalloc((sizeof(*newrec) + template->target_priv_sz),
1396 			 GFP_KERNEL);
1397 	if (!newrec) {
1398 		ret = -ENOMEM;
1399 		goto out_regtgt_failed;
1400 	}
1401 
1402 	idx = ida_alloc(&nvmet_fc_tgtport_cnt, GFP_KERNEL);
1403 	if (idx < 0) {
1404 		ret = -ENOSPC;
1405 		goto out_fail_kfree;
1406 	}
1407 
1408 	if (!get_device(dev) && dev) {
1409 		ret = -ENODEV;
1410 		goto out_ida_put;
1411 	}
1412 
1413 	newrec->fc_target_port.node_name = pinfo->node_name;
1414 	newrec->fc_target_port.port_name = pinfo->port_name;
1415 	if (template->target_priv_sz)
1416 		newrec->fc_target_port.private = &newrec[1];
1417 	else
1418 		newrec->fc_target_port.private = NULL;
1419 	newrec->fc_target_port.port_id = pinfo->port_id;
1420 	newrec->fc_target_port.port_num = idx;
1421 	INIT_LIST_HEAD(&newrec->tgt_list);
1422 	newrec->dev = dev;
1423 	newrec->ops = template;
1424 	spin_lock_init(&newrec->lock);
1425 	INIT_LIST_HEAD(&newrec->ls_rcv_list);
1426 	INIT_LIST_HEAD(&newrec->ls_req_list);
1427 	INIT_LIST_HEAD(&newrec->ls_busylist);
1428 	INIT_LIST_HEAD(&newrec->assoc_list);
1429 	INIT_LIST_HEAD(&newrec->host_list);
1430 	kref_init(&newrec->ref);
1431 	ida_init(&newrec->assoc_cnt);
1432 	newrec->max_sg_cnt = template->max_sgl_segments;
1433 	INIT_WORK(&newrec->put_work, nvmet_fc_put_tgtport_work);
1434 
1435 	ret = nvmet_fc_alloc_ls_iodlist(newrec);
1436 	if (ret) {
1437 		ret = -ENOMEM;
1438 		goto out_free_newrec;
1439 	}
1440 
1441 	nvmet_fc_portentry_rebind_tgt(newrec);
1442 
1443 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1444 	list_add_tail(&newrec->tgt_list, &nvmet_fc_target_list);
1445 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1446 
1447 	*portptr = &newrec->fc_target_port;
1448 	return 0;
1449 
1450 out_free_newrec:
1451 	put_device(dev);
1452 out_ida_put:
1453 	ida_free(&nvmet_fc_tgtport_cnt, idx);
1454 out_fail_kfree:
1455 	kfree(newrec);
1456 out_regtgt_failed:
1457 	*portptr = NULL;
1458 	return ret;
1459 }
1460 EXPORT_SYMBOL_GPL(nvmet_fc_register_targetport);
1461 
1462 
1463 static void
1464 nvmet_fc_free_tgtport(struct kref *ref)
1465 {
1466 	struct nvmet_fc_tgtport *tgtport =
1467 		container_of(ref, struct nvmet_fc_tgtport, ref);
1468 	struct device *dev = tgtport->dev;
1469 	unsigned long flags;
1470 
1471 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1472 	list_del(&tgtport->tgt_list);
1473 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1474 
1475 	nvmet_fc_free_ls_iodlist(tgtport);
1476 
1477 	/* let the LLDD know we've finished tearing it down */
1478 	tgtport->ops->targetport_delete(&tgtport->fc_target_port);
1479 
1480 	ida_free(&nvmet_fc_tgtport_cnt,
1481 			tgtport->fc_target_port.port_num);
1482 
1483 	ida_destroy(&tgtport->assoc_cnt);
1484 
1485 	kfree(tgtport);
1486 
1487 	put_device(dev);
1488 }
1489 
1490 static void
1491 nvmet_fc_tgtport_put(struct nvmet_fc_tgtport *tgtport)
1492 {
1493 	kref_put(&tgtport->ref, nvmet_fc_free_tgtport);
1494 }
1495 
1496 static int
1497 nvmet_fc_tgtport_get(struct nvmet_fc_tgtport *tgtport)
1498 {
1499 	return kref_get_unless_zero(&tgtport->ref);
1500 }
1501 
1502 static void
1503 __nvmet_fc_free_assocs(struct nvmet_fc_tgtport *tgtport)
1504 {
1505 	struct nvmet_fc_tgt_assoc *assoc;
1506 
1507 	rcu_read_lock();
1508 	list_for_each_entry_rcu(assoc, &tgtport->assoc_list, a_list) {
1509 		if (!nvmet_fc_tgt_a_get(assoc))
1510 			continue;
1511 		nvmet_fc_schedule_delete_assoc(assoc);
1512 		nvmet_fc_tgt_a_put(assoc);
1513 	}
1514 	rcu_read_unlock();
1515 }
1516 
1517 /**
1518  * nvmet_fc_invalidate_host - transport entry point called by an LLDD
1519  *                       to remove references to a hosthandle for LS's.
1520  *
1521  * The nvmet-fc layer ensures that any references to the hosthandle
1522  * on the targetport are forgotten (set to NULL).  The LLDD will
1523  * typically call this when a login with a remote host port has been
1524  * lost, thus LS's for the remote host port are no longer possible.
1525  *
1526  * If an LS request is outstanding to the targetport/hosthandle (or
1527  * issued concurrently with the call to invalidate the host), the
1528  * LLDD is responsible for terminating/aborting the LS and completing
1529  * the LS request. It is recommended that these terminations/aborts
1530  * occur after calling to invalidate the host handle to avoid additional
1531  * retries by the nvmet-fc transport. The nvmet-fc transport may
1532  * continue to reference host handle while it cleans up outstanding
1533  * NVME associations. The nvmet-fc transport will call the
1534  * ops->host_release() callback to notify the LLDD that all references
1535  * are complete and the related host handle can be recovered.
1536  * Note: if there are no references, the callback may be called before
1537  * the invalidate host call returns.
1538  *
1539  * @target_port: pointer to the (registered) target port that a prior
1540  *              LS was received on and which supplied the transport the
1541  *              hosthandle.
1542  * @hosthandle: the handle (pointer) that represents the host port
1543  *              that no longer has connectivity and that LS's should
1544  *              no longer be directed to.
1545  */
1546 void
1547 nvmet_fc_invalidate_host(struct nvmet_fc_target_port *target_port,
1548 			void *hosthandle)
1549 {
1550 	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
1551 	struct nvmet_fc_tgt_assoc *assoc, *next;
1552 	unsigned long flags;
1553 	bool noassoc = true;
1554 
1555 	spin_lock_irqsave(&tgtport->lock, flags);
1556 	list_for_each_entry_safe(assoc, next,
1557 				&tgtport->assoc_list, a_list) {
1558 		if (assoc->hostport->hosthandle != hosthandle)
1559 			continue;
1560 		if (!nvmet_fc_tgt_a_get(assoc))
1561 			continue;
1562 		assoc->hostport->invalid = 1;
1563 		noassoc = false;
1564 		nvmet_fc_schedule_delete_assoc(assoc);
1565 		nvmet_fc_tgt_a_put(assoc);
1566 	}
1567 	spin_unlock_irqrestore(&tgtport->lock, flags);
1568 
1569 	/* if there's nothing to wait for - call the callback */
1570 	if (noassoc && tgtport->ops->host_release)
1571 		tgtport->ops->host_release(hosthandle);
1572 }
1573 EXPORT_SYMBOL_GPL(nvmet_fc_invalidate_host);
1574 
1575 /*
1576  * nvmet layer has called to terminate an association
1577  */
1578 static void
1579 nvmet_fc_delete_ctrl(struct nvmet_ctrl *ctrl)
1580 {
1581 	struct nvmet_fc_tgtport *tgtport, *next;
1582 	struct nvmet_fc_tgt_assoc *assoc;
1583 	struct nvmet_fc_tgt_queue *queue;
1584 	unsigned long flags;
1585 	bool found_ctrl = false;
1586 
1587 	/* this is a bit ugly, but don't want to make locks layered */
1588 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1589 	list_for_each_entry_safe(tgtport, next, &nvmet_fc_target_list,
1590 			tgt_list) {
1591 		if (!nvmet_fc_tgtport_get(tgtport))
1592 			continue;
1593 		spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1594 
1595 		rcu_read_lock();
1596 		list_for_each_entry_rcu(assoc, &tgtport->assoc_list, a_list) {
1597 			queue = assoc->queues[0];
1598 			if (queue && queue->nvme_sq.ctrl == ctrl) {
1599 				if (nvmet_fc_tgt_a_get(assoc))
1600 					found_ctrl = true;
1601 				break;
1602 			}
1603 		}
1604 		rcu_read_unlock();
1605 
1606 		nvmet_fc_tgtport_put(tgtport);
1607 
1608 		if (found_ctrl) {
1609 			nvmet_fc_schedule_delete_assoc(assoc);
1610 			nvmet_fc_tgt_a_put(assoc);
1611 			return;
1612 		}
1613 
1614 		spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
1615 	}
1616 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
1617 }
1618 
1619 /**
1620  * nvmet_fc_unregister_targetport - transport entry point called by an
1621  *                              LLDD to deregister/remove a previously
1622  *                              registered a local NVME subsystem FC port.
1623  * @target_port: pointer to the (registered) target port that is to be
1624  *               deregistered.
1625  *
1626  * Returns:
1627  * a completion status. Must be 0 upon success; a negative errno
1628  * (ex: -ENXIO) upon failure.
1629  */
1630 int
1631 nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *target_port)
1632 {
1633 	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
1634 
1635 	nvmet_fc_portentry_unbind_tgt(tgtport);
1636 
1637 	/* terminate any outstanding associations */
1638 	__nvmet_fc_free_assocs(tgtport);
1639 
1640 	flush_workqueue(nvmet_wq);
1641 
1642 	/*
1643 	 * should terminate LS's as well. However, LS's will be generated
1644 	 * at the tail end of association termination, so they likely don't
1645 	 * exist yet. And even if they did, it's worthwhile to just let
1646 	 * them finish and targetport ref counting will clean things up.
1647 	 */
1648 
1649 	nvmet_fc_tgtport_put(tgtport);
1650 
1651 	return 0;
1652 }
1653 EXPORT_SYMBOL_GPL(nvmet_fc_unregister_targetport);
1654 
1655 
1656 /* ********************** FC-NVME LS RCV Handling ************************* */
1657 
1658 
1659 static void
1660 nvmet_fc_ls_create_association(struct nvmet_fc_tgtport *tgtport,
1661 			struct nvmet_fc_ls_iod *iod)
1662 {
1663 	struct fcnvme_ls_cr_assoc_rqst *rqst = &iod->rqstbuf->rq_cr_assoc;
1664 	struct fcnvme_ls_cr_assoc_acc *acc = &iod->rspbuf->rsp_cr_assoc;
1665 	struct nvmet_fc_tgt_queue *queue;
1666 	int ret = 0;
1667 
1668 	memset(acc, 0, sizeof(*acc));
1669 
1670 	/*
1671 	 * FC-NVME spec changes. There are initiators sending different
1672 	 * lengths as padding sizes for Create Association Cmd descriptor
1673 	 * was incorrect.
1674 	 * Accept anything of "minimum" length. Assume format per 1.15
1675 	 * spec (with HOSTID reduced to 16 bytes), ignore how long the
1676 	 * trailing pad length is.
1677 	 */
1678 	if (iod->rqstdatalen < FCNVME_LSDESC_CRA_RQST_MINLEN)
1679 		ret = VERR_CR_ASSOC_LEN;
1680 	else if (be32_to_cpu(rqst->desc_list_len) <
1681 			FCNVME_LSDESC_CRA_RQST_MIN_LISTLEN)
1682 		ret = VERR_CR_ASSOC_RQST_LEN;
1683 	else if (rqst->assoc_cmd.desc_tag !=
1684 			cpu_to_be32(FCNVME_LSDESC_CREATE_ASSOC_CMD))
1685 		ret = VERR_CR_ASSOC_CMD;
1686 	else if (be32_to_cpu(rqst->assoc_cmd.desc_len) <
1687 			FCNVME_LSDESC_CRA_CMD_DESC_MIN_DESCLEN)
1688 		ret = VERR_CR_ASSOC_CMD_LEN;
1689 	else if (!rqst->assoc_cmd.ersp_ratio ||
1690 		 (be16_to_cpu(rqst->assoc_cmd.ersp_ratio) >=
1691 				be16_to_cpu(rqst->assoc_cmd.sqsize)))
1692 		ret = VERR_ERSP_RATIO;
1693 
1694 	else {
1695 		/* new association w/ admin queue */
1696 		iod->assoc = nvmet_fc_alloc_target_assoc(
1697 						tgtport, iod->hosthandle);
1698 		if (!iod->assoc)
1699 			ret = VERR_ASSOC_ALLOC_FAIL;
1700 		else {
1701 			queue = nvmet_fc_alloc_target_queue(iod->assoc, 0,
1702 					be16_to_cpu(rqst->assoc_cmd.sqsize));
1703 			if (!queue) {
1704 				ret = VERR_QUEUE_ALLOC_FAIL;
1705 				nvmet_fc_tgt_a_put(iod->assoc);
1706 			}
1707 		}
1708 	}
1709 
1710 	if (ret) {
1711 		dev_err(tgtport->dev,
1712 			"Create Association LS failed: %s\n",
1713 			validation_errors[ret]);
1714 		iod->lsrsp->rsplen = nvme_fc_format_rjt(acc,
1715 				sizeof(*acc), rqst->w0.ls_cmd,
1716 				FCNVME_RJT_RC_LOGIC,
1717 				FCNVME_RJT_EXP_NONE, 0);
1718 		return;
1719 	}
1720 
1721 	queue->ersp_ratio = be16_to_cpu(rqst->assoc_cmd.ersp_ratio);
1722 	atomic_set(&queue->connected, 1);
1723 	queue->sqhd = 0;	/* best place to init value */
1724 
1725 	dev_info(tgtport->dev,
1726 		"{%d:%d} Association created\n",
1727 		tgtport->fc_target_port.port_num, iod->assoc->a_id);
1728 
1729 	/* format a response */
1730 
1731 	iod->lsrsp->rsplen = sizeof(*acc);
1732 
1733 	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
1734 			fcnvme_lsdesc_len(
1735 				sizeof(struct fcnvme_ls_cr_assoc_acc)),
1736 			FCNVME_LS_CREATE_ASSOCIATION);
1737 	acc->associd.desc_tag = cpu_to_be32(FCNVME_LSDESC_ASSOC_ID);
1738 	acc->associd.desc_len =
1739 			fcnvme_lsdesc_len(
1740 				sizeof(struct fcnvme_lsdesc_assoc_id));
1741 	acc->associd.association_id =
1742 			cpu_to_be64(nvmet_fc_makeconnid(iod->assoc, 0));
1743 	acc->connectid.desc_tag = cpu_to_be32(FCNVME_LSDESC_CONN_ID);
1744 	acc->connectid.desc_len =
1745 			fcnvme_lsdesc_len(
1746 				sizeof(struct fcnvme_lsdesc_conn_id));
1747 	acc->connectid.connection_id = acc->associd.association_id;
1748 }
1749 
1750 static void
1751 nvmet_fc_ls_create_connection(struct nvmet_fc_tgtport *tgtport,
1752 			struct nvmet_fc_ls_iod *iod)
1753 {
1754 	struct fcnvme_ls_cr_conn_rqst *rqst = &iod->rqstbuf->rq_cr_conn;
1755 	struct fcnvme_ls_cr_conn_acc *acc = &iod->rspbuf->rsp_cr_conn;
1756 	struct nvmet_fc_tgt_queue *queue;
1757 	int ret = 0;
1758 
1759 	memset(acc, 0, sizeof(*acc));
1760 
1761 	if (iod->rqstdatalen < sizeof(struct fcnvme_ls_cr_conn_rqst))
1762 		ret = VERR_CR_CONN_LEN;
1763 	else if (rqst->desc_list_len !=
1764 			fcnvme_lsdesc_len(
1765 				sizeof(struct fcnvme_ls_cr_conn_rqst)))
1766 		ret = VERR_CR_CONN_RQST_LEN;
1767 	else if (rqst->associd.desc_tag != cpu_to_be32(FCNVME_LSDESC_ASSOC_ID))
1768 		ret = VERR_ASSOC_ID;
1769 	else if (rqst->associd.desc_len !=
1770 			fcnvme_lsdesc_len(
1771 				sizeof(struct fcnvme_lsdesc_assoc_id)))
1772 		ret = VERR_ASSOC_ID_LEN;
1773 	else if (rqst->connect_cmd.desc_tag !=
1774 			cpu_to_be32(FCNVME_LSDESC_CREATE_CONN_CMD))
1775 		ret = VERR_CR_CONN_CMD;
1776 	else if (rqst->connect_cmd.desc_len !=
1777 			fcnvme_lsdesc_len(
1778 				sizeof(struct fcnvme_lsdesc_cr_conn_cmd)))
1779 		ret = VERR_CR_CONN_CMD_LEN;
1780 	else if (!rqst->connect_cmd.ersp_ratio ||
1781 		 (be16_to_cpu(rqst->connect_cmd.ersp_ratio) >=
1782 				be16_to_cpu(rqst->connect_cmd.sqsize)))
1783 		ret = VERR_ERSP_RATIO;
1784 
1785 	else {
1786 		/* new io queue */
1787 		iod->assoc = nvmet_fc_find_target_assoc(tgtport,
1788 				be64_to_cpu(rqst->associd.association_id));
1789 		if (!iod->assoc)
1790 			ret = VERR_NO_ASSOC;
1791 		else {
1792 			queue = nvmet_fc_alloc_target_queue(iod->assoc,
1793 					be16_to_cpu(rqst->connect_cmd.qid),
1794 					be16_to_cpu(rqst->connect_cmd.sqsize));
1795 			if (!queue)
1796 				ret = VERR_QUEUE_ALLOC_FAIL;
1797 
1798 			/* release get taken in nvmet_fc_find_target_assoc */
1799 			nvmet_fc_tgt_a_put(iod->assoc);
1800 		}
1801 	}
1802 
1803 	if (ret) {
1804 		dev_err(tgtport->dev,
1805 			"Create Connection LS failed: %s\n",
1806 			validation_errors[ret]);
1807 		iod->lsrsp->rsplen = nvme_fc_format_rjt(acc,
1808 				sizeof(*acc), rqst->w0.ls_cmd,
1809 				(ret == VERR_NO_ASSOC) ?
1810 					FCNVME_RJT_RC_INV_ASSOC :
1811 					FCNVME_RJT_RC_LOGIC,
1812 				FCNVME_RJT_EXP_NONE, 0);
1813 		return;
1814 	}
1815 
1816 	queue->ersp_ratio = be16_to_cpu(rqst->connect_cmd.ersp_ratio);
1817 	atomic_set(&queue->connected, 1);
1818 	queue->sqhd = 0;	/* best place to init value */
1819 
1820 	/* format a response */
1821 
1822 	iod->lsrsp->rsplen = sizeof(*acc);
1823 
1824 	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
1825 			fcnvme_lsdesc_len(sizeof(struct fcnvme_ls_cr_conn_acc)),
1826 			FCNVME_LS_CREATE_CONNECTION);
1827 	acc->connectid.desc_tag = cpu_to_be32(FCNVME_LSDESC_CONN_ID);
1828 	acc->connectid.desc_len =
1829 			fcnvme_lsdesc_len(
1830 				sizeof(struct fcnvme_lsdesc_conn_id));
1831 	acc->connectid.connection_id =
1832 			cpu_to_be64(nvmet_fc_makeconnid(iod->assoc,
1833 				be16_to_cpu(rqst->connect_cmd.qid)));
1834 }
1835 
1836 /*
1837  * Returns true if the LS response is to be transmit
1838  * Returns false if the LS response is to be delayed
1839  */
1840 static int
1841 nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
1842 			struct nvmet_fc_ls_iod *iod)
1843 {
1844 	struct fcnvme_ls_disconnect_assoc_rqst *rqst =
1845 						&iod->rqstbuf->rq_dis_assoc;
1846 	struct fcnvme_ls_disconnect_assoc_acc *acc =
1847 						&iod->rspbuf->rsp_dis_assoc;
1848 	struct nvmet_fc_tgt_assoc *assoc = NULL;
1849 	struct nvmet_fc_ls_iod *oldls = NULL;
1850 	unsigned long flags;
1851 	int ret = 0;
1852 
1853 	memset(acc, 0, sizeof(*acc));
1854 
1855 	ret = nvmefc_vldt_lsreq_discon_assoc(iod->rqstdatalen, rqst);
1856 	if (!ret) {
1857 		/* match an active association - takes an assoc ref if !NULL */
1858 		assoc = nvmet_fc_find_target_assoc(tgtport,
1859 				be64_to_cpu(rqst->associd.association_id));
1860 		iod->assoc = assoc;
1861 		if (!assoc)
1862 			ret = VERR_NO_ASSOC;
1863 	}
1864 
1865 	if (ret || !assoc) {
1866 		dev_err(tgtport->dev,
1867 			"Disconnect LS failed: %s\n",
1868 			validation_errors[ret]);
1869 		iod->lsrsp->rsplen = nvme_fc_format_rjt(acc,
1870 				sizeof(*acc), rqst->w0.ls_cmd,
1871 				(ret == VERR_NO_ASSOC) ?
1872 					FCNVME_RJT_RC_INV_ASSOC :
1873 					FCNVME_RJT_RC_LOGIC,
1874 				FCNVME_RJT_EXP_NONE, 0);
1875 		return true;
1876 	}
1877 
1878 	/* format a response */
1879 
1880 	iod->lsrsp->rsplen = sizeof(*acc);
1881 
1882 	nvme_fc_format_rsp_hdr(acc, FCNVME_LS_ACC,
1883 			fcnvme_lsdesc_len(
1884 				sizeof(struct fcnvme_ls_disconnect_assoc_acc)),
1885 			FCNVME_LS_DISCONNECT_ASSOC);
1886 
1887 	/*
1888 	 * The rules for LS response says the response cannot
1889 	 * go back until ABTS's have been sent for all outstanding
1890 	 * I/O and a Disconnect Association LS has been sent.
1891 	 * So... save off the Disconnect LS to send the response
1892 	 * later. If there was a prior LS already saved, replace
1893 	 * it with the newer one and send a can't perform reject
1894 	 * on the older one.
1895 	 */
1896 	spin_lock_irqsave(&tgtport->lock, flags);
1897 	oldls = assoc->rcv_disconn;
1898 	assoc->rcv_disconn = iod;
1899 	spin_unlock_irqrestore(&tgtport->lock, flags);
1900 
1901 	if (oldls) {
1902 		dev_info(tgtport->dev,
1903 			"{%d:%d} Multiple Disconnect Association LS's "
1904 			"received\n",
1905 			tgtport->fc_target_port.port_num, assoc->a_id);
1906 		/* overwrite good response with bogus failure */
1907 		oldls->lsrsp->rsplen = nvme_fc_format_rjt(oldls->rspbuf,
1908 						sizeof(*iod->rspbuf),
1909 						/* ok to use rqst, LS is same */
1910 						rqst->w0.ls_cmd,
1911 						FCNVME_RJT_RC_UNAB,
1912 						FCNVME_RJT_EXP_NONE, 0);
1913 		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
1914 	}
1915 
1916 	nvmet_fc_schedule_delete_assoc(assoc);
1917 	nvmet_fc_tgt_a_put(assoc);
1918 
1919 	return false;
1920 }
1921 
1922 
1923 /* *********************** NVME Ctrl Routines **************************** */
1924 
1925 
1926 static void nvmet_fc_fcp_nvme_cmd_done(struct nvmet_req *nvme_req);
1927 
1928 static const struct nvmet_fabrics_ops nvmet_fc_tgt_fcp_ops;
1929 
1930 static void
1931 nvmet_fc_xmt_ls_rsp_done(struct nvmefc_ls_rsp *lsrsp)
1932 {
1933 	struct nvmet_fc_ls_iod *iod = lsrsp->nvme_fc_private;
1934 	struct nvmet_fc_tgtport *tgtport = iod->tgtport;
1935 
1936 	fc_dma_sync_single_for_cpu(tgtport->dev, iod->rspdma,
1937 				sizeof(*iod->rspbuf), DMA_TO_DEVICE);
1938 	nvmet_fc_free_ls_iod(tgtport, iod);
1939 	nvmet_fc_tgtport_put(tgtport);
1940 }
1941 
1942 static void
1943 nvmet_fc_xmt_ls_rsp(struct nvmet_fc_tgtport *tgtport,
1944 				struct nvmet_fc_ls_iod *iod)
1945 {
1946 	int ret;
1947 
1948 	fc_dma_sync_single_for_device(tgtport->dev, iod->rspdma,
1949 				  sizeof(*iod->rspbuf), DMA_TO_DEVICE);
1950 
1951 	ret = tgtport->ops->xmt_ls_rsp(&tgtport->fc_target_port, iod->lsrsp);
1952 	if (ret)
1953 		nvmet_fc_xmt_ls_rsp_done(iod->lsrsp);
1954 }
1955 
1956 /*
1957  * Actual processing routine for received FC-NVME LS Requests from the LLD
1958  */
1959 static void
1960 nvmet_fc_handle_ls_rqst(struct nvmet_fc_tgtport *tgtport,
1961 			struct nvmet_fc_ls_iod *iod)
1962 {
1963 	struct fcnvme_ls_rqst_w0 *w0 = &iod->rqstbuf->rq_cr_assoc.w0;
1964 	bool sendrsp = true;
1965 
1966 	iod->lsrsp->nvme_fc_private = iod;
1967 	iod->lsrsp->rspbuf = iod->rspbuf;
1968 	iod->lsrsp->rspdma = iod->rspdma;
1969 	iod->lsrsp->done = nvmet_fc_xmt_ls_rsp_done;
1970 	/* Be preventative. handlers will later set to valid length */
1971 	iod->lsrsp->rsplen = 0;
1972 
1973 	iod->assoc = NULL;
1974 
1975 	/*
1976 	 * handlers:
1977 	 *   parse request input, execute the request, and format the
1978 	 *   LS response
1979 	 */
1980 	switch (w0->ls_cmd) {
1981 	case FCNVME_LS_CREATE_ASSOCIATION:
1982 		/* Creates Association and initial Admin Queue/Connection */
1983 		nvmet_fc_ls_create_association(tgtport, iod);
1984 		break;
1985 	case FCNVME_LS_CREATE_CONNECTION:
1986 		/* Creates an IO Queue/Connection */
1987 		nvmet_fc_ls_create_connection(tgtport, iod);
1988 		break;
1989 	case FCNVME_LS_DISCONNECT_ASSOC:
1990 		/* Terminate a Queue/Connection or the Association */
1991 		sendrsp = nvmet_fc_ls_disconnect(tgtport, iod);
1992 		break;
1993 	default:
1994 		iod->lsrsp->rsplen = nvme_fc_format_rjt(iod->rspbuf,
1995 				sizeof(*iod->rspbuf), w0->ls_cmd,
1996 				FCNVME_RJT_RC_INVAL, FCNVME_RJT_EXP_NONE, 0);
1997 	}
1998 
1999 	if (sendrsp)
2000 		nvmet_fc_xmt_ls_rsp(tgtport, iod);
2001 }
2002 
2003 /*
2004  * Actual processing routine for received FC-NVME LS Requests from the LLD
2005  */
2006 static void
2007 nvmet_fc_handle_ls_rqst_work(struct work_struct *work)
2008 {
2009 	struct nvmet_fc_ls_iod *iod =
2010 		container_of(work, struct nvmet_fc_ls_iod, work);
2011 	struct nvmet_fc_tgtport *tgtport = iod->tgtport;
2012 
2013 	nvmet_fc_handle_ls_rqst(tgtport, iod);
2014 }
2015 
2016 
2017 /**
2018  * nvmet_fc_rcv_ls_req - transport entry point called by an LLDD
2019  *                       upon the reception of a NVME LS request.
2020  *
2021  * The nvmet-fc layer will copy payload to an internal structure for
2022  * processing.  As such, upon completion of the routine, the LLDD may
2023  * immediately free/reuse the LS request buffer passed in the call.
2024  *
2025  * If this routine returns error, the LLDD should abort the exchange.
2026  *
2027  * @target_port: pointer to the (registered) target port the LS was
2028  *              received on.
2029  * @hosthandle: pointer to the host specific data, gets stored in iod.
2030  * @lsrsp:      pointer to a lsrsp structure to be used to reference
2031  *              the exchange corresponding to the LS.
2032  * @lsreqbuf:   pointer to the buffer containing the LS Request
2033  * @lsreqbuf_len: length, in bytes, of the received LS request
2034  */
2035 int
2036 nvmet_fc_rcv_ls_req(struct nvmet_fc_target_port *target_port,
2037 			void *hosthandle,
2038 			struct nvmefc_ls_rsp *lsrsp,
2039 			void *lsreqbuf, u32 lsreqbuf_len)
2040 {
2041 	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
2042 	struct nvmet_fc_ls_iod *iod;
2043 	struct fcnvme_ls_rqst_w0 *w0 = (struct fcnvme_ls_rqst_w0 *)lsreqbuf;
2044 
2045 	if (lsreqbuf_len > sizeof(union nvmefc_ls_requests)) {
2046 		dev_info(tgtport->dev,
2047 			"RCV %s LS failed: payload too large (%d)\n",
2048 			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
2049 				nvmefc_ls_names[w0->ls_cmd] : "",
2050 			lsreqbuf_len);
2051 		return -E2BIG;
2052 	}
2053 
2054 	if (!nvmet_fc_tgtport_get(tgtport)) {
2055 		dev_info(tgtport->dev,
2056 			"RCV %s LS failed: target deleting\n",
2057 			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
2058 				nvmefc_ls_names[w0->ls_cmd] : "");
2059 		return -ESHUTDOWN;
2060 	}
2061 
2062 	iod = nvmet_fc_alloc_ls_iod(tgtport);
2063 	if (!iod) {
2064 		dev_info(tgtport->dev,
2065 			"RCV %s LS failed: context allocation failed\n",
2066 			(w0->ls_cmd <= NVME_FC_LAST_LS_CMD_VALUE) ?
2067 				nvmefc_ls_names[w0->ls_cmd] : "");
2068 		nvmet_fc_tgtport_put(tgtport);
2069 		return -ENOENT;
2070 	}
2071 
2072 	iod->lsrsp = lsrsp;
2073 	iod->fcpreq = NULL;
2074 	memcpy(iod->rqstbuf, lsreqbuf, lsreqbuf_len);
2075 	iod->rqstdatalen = lsreqbuf_len;
2076 	iod->hosthandle = hosthandle;
2077 
2078 	queue_work(nvmet_wq, &iod->work);
2079 
2080 	return 0;
2081 }
2082 EXPORT_SYMBOL_GPL(nvmet_fc_rcv_ls_req);
2083 
2084 
2085 /*
2086  * **********************
2087  * Start of FCP handling
2088  * **********************
2089  */
2090 
2091 static int
2092 nvmet_fc_alloc_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
2093 {
2094 	struct scatterlist *sg;
2095 	unsigned int nent;
2096 
2097 	sg = sgl_alloc(fod->req.transfer_len, GFP_KERNEL, &nent);
2098 	if (!sg)
2099 		goto out;
2100 
2101 	fod->data_sg = sg;
2102 	fod->data_sg_cnt = nent;
2103 	fod->data_sg_cnt = fc_dma_map_sg(fod->tgtport->dev, sg, nent,
2104 				((fod->io_dir == NVMET_FCP_WRITE) ?
2105 					DMA_FROM_DEVICE : DMA_TO_DEVICE));
2106 				/* note: write from initiator perspective */
2107 	fod->next_sg = fod->data_sg;
2108 
2109 	return 0;
2110 
2111 out:
2112 	return NVME_SC_INTERNAL;
2113 }
2114 
2115 static void
2116 nvmet_fc_free_tgt_pgs(struct nvmet_fc_fcp_iod *fod)
2117 {
2118 	if (!fod->data_sg || !fod->data_sg_cnt)
2119 		return;
2120 
2121 	fc_dma_unmap_sg(fod->tgtport->dev, fod->data_sg, fod->data_sg_cnt,
2122 				((fod->io_dir == NVMET_FCP_WRITE) ?
2123 					DMA_FROM_DEVICE : DMA_TO_DEVICE));
2124 	sgl_free(fod->data_sg);
2125 	fod->data_sg = NULL;
2126 	fod->data_sg_cnt = 0;
2127 }
2128 
2129 
2130 static bool
2131 queue_90percent_full(struct nvmet_fc_tgt_queue *q, u32 sqhd)
2132 {
2133 	u32 sqtail, used;
2134 
2135 	/* egad, this is ugly. And sqtail is just a best guess */
2136 	sqtail = atomic_read(&q->sqtail) % q->sqsize;
2137 
2138 	used = (sqtail < sqhd) ? (sqtail + q->sqsize - sqhd) : (sqtail - sqhd);
2139 	return ((used * 10) >= (((u32)(q->sqsize - 1) * 9)));
2140 }
2141 
2142 /*
2143  * Prep RSP payload.
2144  * May be a NVMET_FCOP_RSP or NVMET_FCOP_READDATA_RSP op
2145  */
2146 static void
2147 nvmet_fc_prep_fcp_rsp(struct nvmet_fc_tgtport *tgtport,
2148 				struct nvmet_fc_fcp_iod *fod)
2149 {
2150 	struct nvme_fc_ersp_iu *ersp = &fod->rspiubuf;
2151 	struct nvme_common_command *sqe = &fod->cmdiubuf.sqe.common;
2152 	struct nvme_completion *cqe = &ersp->cqe;
2153 	u32 *cqewd = (u32 *)cqe;
2154 	bool send_ersp = false;
2155 	u32 rsn, rspcnt, xfr_length;
2156 
2157 	if (fod->fcpreq->op == NVMET_FCOP_READDATA_RSP)
2158 		xfr_length = fod->req.transfer_len;
2159 	else
2160 		xfr_length = fod->offset;
2161 
2162 	/*
2163 	 * check to see if we can send a 0's rsp.
2164 	 *   Note: to send a 0's response, the NVME-FC host transport will
2165 	 *   recreate the CQE. The host transport knows: sq id, SQHD (last
2166 	 *   seen in an ersp), and command_id. Thus it will create a
2167 	 *   zero-filled CQE with those known fields filled in. Transport
2168 	 *   must send an ersp for any condition where the cqe won't match
2169 	 *   this.
2170 	 *
2171 	 * Here are the FC-NVME mandated cases where we must send an ersp:
2172 	 *  every N responses, where N=ersp_ratio
2173 	 *  force fabric commands to send ersp's (not in FC-NVME but good
2174 	 *    practice)
2175 	 *  normal cmds: any time status is non-zero, or status is zero
2176 	 *     but words 0 or 1 are non-zero.
2177 	 *  the SQ is 90% or more full
2178 	 *  the cmd is a fused command
2179 	 *  transferred data length not equal to cmd iu length
2180 	 */
2181 	rspcnt = atomic_inc_return(&fod->queue->zrspcnt);
2182 	if (!(rspcnt % fod->queue->ersp_ratio) ||
2183 	    nvme_is_fabrics((struct nvme_command *) sqe) ||
2184 	    xfr_length != fod->req.transfer_len ||
2185 	    (le16_to_cpu(cqe->status) & 0xFFFE) || cqewd[0] || cqewd[1] ||
2186 	    (sqe->flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND)) ||
2187 	    queue_90percent_full(fod->queue, le16_to_cpu(cqe->sq_head)))
2188 		send_ersp = true;
2189 
2190 	/* re-set the fields */
2191 	fod->fcpreq->rspaddr = ersp;
2192 	fod->fcpreq->rspdma = fod->rspdma;
2193 
2194 	if (!send_ersp) {
2195 		memset(ersp, 0, NVME_FC_SIZEOF_ZEROS_RSP);
2196 		fod->fcpreq->rsplen = NVME_FC_SIZEOF_ZEROS_RSP;
2197 	} else {
2198 		ersp->iu_len = cpu_to_be16(sizeof(*ersp)/sizeof(u32));
2199 		rsn = atomic_inc_return(&fod->queue->rsn);
2200 		ersp->rsn = cpu_to_be32(rsn);
2201 		ersp->xfrd_len = cpu_to_be32(xfr_length);
2202 		fod->fcpreq->rsplen = sizeof(*ersp);
2203 	}
2204 
2205 	fc_dma_sync_single_for_device(tgtport->dev, fod->rspdma,
2206 				  sizeof(fod->rspiubuf), DMA_TO_DEVICE);
2207 }
2208 
2209 static void nvmet_fc_xmt_fcp_op_done(struct nvmefc_tgt_fcp_req *fcpreq);
2210 
2211 static void
2212 nvmet_fc_abort_op(struct nvmet_fc_tgtport *tgtport,
2213 				struct nvmet_fc_fcp_iod *fod)
2214 {
2215 	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
2216 
2217 	/* data no longer needed */
2218 	nvmet_fc_free_tgt_pgs(fod);
2219 
2220 	/*
2221 	 * if an ABTS was received or we issued the fcp_abort early
2222 	 * don't call abort routine again.
2223 	 */
2224 	/* no need to take lock - lock was taken earlier to get here */
2225 	if (!fod->aborted)
2226 		tgtport->ops->fcp_abort(&tgtport->fc_target_port, fcpreq);
2227 
2228 	nvmet_fc_free_fcp_iod(fod->queue, fod);
2229 }
2230 
2231 static void
2232 nvmet_fc_xmt_fcp_rsp(struct nvmet_fc_tgtport *tgtport,
2233 				struct nvmet_fc_fcp_iod *fod)
2234 {
2235 	int ret;
2236 
2237 	fod->fcpreq->op = NVMET_FCOP_RSP;
2238 	fod->fcpreq->timeout = 0;
2239 
2240 	nvmet_fc_prep_fcp_rsp(tgtport, fod);
2241 
2242 	ret = tgtport->ops->fcp_op(&tgtport->fc_target_port, fod->fcpreq);
2243 	if (ret)
2244 		nvmet_fc_abort_op(tgtport, fod);
2245 }
2246 
2247 static void
2248 nvmet_fc_transfer_fcp_data(struct nvmet_fc_tgtport *tgtport,
2249 				struct nvmet_fc_fcp_iod *fod, u8 op)
2250 {
2251 	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
2252 	struct scatterlist *sg = fod->next_sg;
2253 	unsigned long flags;
2254 	u32 remaininglen = fod->req.transfer_len - fod->offset;
2255 	u32 tlen = 0;
2256 	int ret;
2257 
2258 	fcpreq->op = op;
2259 	fcpreq->offset = fod->offset;
2260 	fcpreq->timeout = NVME_FC_TGTOP_TIMEOUT_SEC;
2261 
2262 	/*
2263 	 * for next sequence:
2264 	 *  break at a sg element boundary
2265 	 *  attempt to keep sequence length capped at
2266 	 *    NVMET_FC_MAX_SEQ_LENGTH but allow sequence to
2267 	 *    be longer if a single sg element is larger
2268 	 *    than that amount. This is done to avoid creating
2269 	 *    a new sg list to use for the tgtport api.
2270 	 */
2271 	fcpreq->sg = sg;
2272 	fcpreq->sg_cnt = 0;
2273 	while (tlen < remaininglen &&
2274 	       fcpreq->sg_cnt < tgtport->max_sg_cnt &&
2275 	       tlen + sg_dma_len(sg) < NVMET_FC_MAX_SEQ_LENGTH) {
2276 		fcpreq->sg_cnt++;
2277 		tlen += sg_dma_len(sg);
2278 		sg = sg_next(sg);
2279 	}
2280 	if (tlen < remaininglen && fcpreq->sg_cnt == 0) {
2281 		fcpreq->sg_cnt++;
2282 		tlen += min_t(u32, sg_dma_len(sg), remaininglen);
2283 		sg = sg_next(sg);
2284 	}
2285 	if (tlen < remaininglen)
2286 		fod->next_sg = sg;
2287 	else
2288 		fod->next_sg = NULL;
2289 
2290 	fcpreq->transfer_length = tlen;
2291 	fcpreq->transferred_length = 0;
2292 	fcpreq->fcp_error = 0;
2293 	fcpreq->rsplen = 0;
2294 
2295 	/*
2296 	 * If the last READDATA request: check if LLDD supports
2297 	 * combined xfr with response.
2298 	 */
2299 	if ((op == NVMET_FCOP_READDATA) &&
2300 	    ((fod->offset + fcpreq->transfer_length) == fod->req.transfer_len) &&
2301 	    (tgtport->ops->target_features & NVMET_FCTGTFEAT_READDATA_RSP)) {
2302 		fcpreq->op = NVMET_FCOP_READDATA_RSP;
2303 		nvmet_fc_prep_fcp_rsp(tgtport, fod);
2304 	}
2305 
2306 	ret = tgtport->ops->fcp_op(&tgtport->fc_target_port, fod->fcpreq);
2307 	if (ret) {
2308 		/*
2309 		 * should be ok to set w/o lock as its in the thread of
2310 		 * execution (not an async timer routine) and doesn't
2311 		 * contend with any clearing action
2312 		 */
2313 		fod->abort = true;
2314 
2315 		if (op == NVMET_FCOP_WRITEDATA) {
2316 			spin_lock_irqsave(&fod->flock, flags);
2317 			fod->writedataactive = false;
2318 			spin_unlock_irqrestore(&fod->flock, flags);
2319 			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
2320 		} else /* NVMET_FCOP_READDATA or NVMET_FCOP_READDATA_RSP */ {
2321 			fcpreq->fcp_error = ret;
2322 			fcpreq->transferred_length = 0;
2323 			nvmet_fc_xmt_fcp_op_done(fod->fcpreq);
2324 		}
2325 	}
2326 }
2327 
2328 static inline bool
2329 __nvmet_fc_fod_op_abort(struct nvmet_fc_fcp_iod *fod, bool abort)
2330 {
2331 	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
2332 	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
2333 
2334 	/* if in the middle of an io and we need to tear down */
2335 	if (abort) {
2336 		if (fcpreq->op == NVMET_FCOP_WRITEDATA) {
2337 			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
2338 			return true;
2339 		}
2340 
2341 		nvmet_fc_abort_op(tgtport, fod);
2342 		return true;
2343 	}
2344 
2345 	return false;
2346 }
2347 
2348 /*
2349  * actual done handler for FCP operations when completed by the lldd
2350  */
2351 static void
2352 nvmet_fc_fod_op_done(struct nvmet_fc_fcp_iod *fod)
2353 {
2354 	struct nvmefc_tgt_fcp_req *fcpreq = fod->fcpreq;
2355 	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
2356 	unsigned long flags;
2357 	bool abort;
2358 
2359 	spin_lock_irqsave(&fod->flock, flags);
2360 	abort = fod->abort;
2361 	fod->writedataactive = false;
2362 	spin_unlock_irqrestore(&fod->flock, flags);
2363 
2364 	switch (fcpreq->op) {
2365 
2366 	case NVMET_FCOP_WRITEDATA:
2367 		if (__nvmet_fc_fod_op_abort(fod, abort))
2368 			return;
2369 		if (fcpreq->fcp_error ||
2370 		    fcpreq->transferred_length != fcpreq->transfer_length) {
2371 			spin_lock_irqsave(&fod->flock, flags);
2372 			fod->abort = true;
2373 			spin_unlock_irqrestore(&fod->flock, flags);
2374 
2375 			nvmet_req_complete(&fod->req, NVME_SC_INTERNAL);
2376 			return;
2377 		}
2378 
2379 		fod->offset += fcpreq->transferred_length;
2380 		if (fod->offset != fod->req.transfer_len) {
2381 			spin_lock_irqsave(&fod->flock, flags);
2382 			fod->writedataactive = true;
2383 			spin_unlock_irqrestore(&fod->flock, flags);
2384 
2385 			/* transfer the next chunk */
2386 			nvmet_fc_transfer_fcp_data(tgtport, fod,
2387 						NVMET_FCOP_WRITEDATA);
2388 			return;
2389 		}
2390 
2391 		/* data transfer complete, resume with nvmet layer */
2392 		fod->req.execute(&fod->req);
2393 		break;
2394 
2395 	case NVMET_FCOP_READDATA:
2396 	case NVMET_FCOP_READDATA_RSP:
2397 		if (__nvmet_fc_fod_op_abort(fod, abort))
2398 			return;
2399 		if (fcpreq->fcp_error ||
2400 		    fcpreq->transferred_length != fcpreq->transfer_length) {
2401 			nvmet_fc_abort_op(tgtport, fod);
2402 			return;
2403 		}
2404 
2405 		/* success */
2406 
2407 		if (fcpreq->op == NVMET_FCOP_READDATA_RSP) {
2408 			/* data no longer needed */
2409 			nvmet_fc_free_tgt_pgs(fod);
2410 			nvmet_fc_free_fcp_iod(fod->queue, fod);
2411 			return;
2412 		}
2413 
2414 		fod->offset += fcpreq->transferred_length;
2415 		if (fod->offset != fod->req.transfer_len) {
2416 			/* transfer the next chunk */
2417 			nvmet_fc_transfer_fcp_data(tgtport, fod,
2418 						NVMET_FCOP_READDATA);
2419 			return;
2420 		}
2421 
2422 		/* data transfer complete, send response */
2423 
2424 		/* data no longer needed */
2425 		nvmet_fc_free_tgt_pgs(fod);
2426 
2427 		nvmet_fc_xmt_fcp_rsp(tgtport, fod);
2428 
2429 		break;
2430 
2431 	case NVMET_FCOP_RSP:
2432 		if (__nvmet_fc_fod_op_abort(fod, abort))
2433 			return;
2434 		nvmet_fc_free_fcp_iod(fod->queue, fod);
2435 		break;
2436 
2437 	default:
2438 		break;
2439 	}
2440 }
2441 
2442 static void
2443 nvmet_fc_xmt_fcp_op_done(struct nvmefc_tgt_fcp_req *fcpreq)
2444 {
2445 	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
2446 
2447 	nvmet_fc_fod_op_done(fod);
2448 }
2449 
2450 /*
2451  * actual completion handler after execution by the nvmet layer
2452  */
2453 static void
2454 __nvmet_fc_fcp_nvme_cmd_done(struct nvmet_fc_tgtport *tgtport,
2455 			struct nvmet_fc_fcp_iod *fod, int status)
2456 {
2457 	struct nvme_common_command *sqe = &fod->cmdiubuf.sqe.common;
2458 	struct nvme_completion *cqe = &fod->rspiubuf.cqe;
2459 	unsigned long flags;
2460 	bool abort;
2461 
2462 	spin_lock_irqsave(&fod->flock, flags);
2463 	abort = fod->abort;
2464 	spin_unlock_irqrestore(&fod->flock, flags);
2465 
2466 	/* if we have a CQE, snoop the last sq_head value */
2467 	if (!status)
2468 		fod->queue->sqhd = cqe->sq_head;
2469 
2470 	if (abort) {
2471 		nvmet_fc_abort_op(tgtport, fod);
2472 		return;
2473 	}
2474 
2475 	/* if an error handling the cmd post initial parsing */
2476 	if (status) {
2477 		/* fudge up a failed CQE status for our transport error */
2478 		memset(cqe, 0, sizeof(*cqe));
2479 		cqe->sq_head = fod->queue->sqhd;	/* echo last cqe sqhd */
2480 		cqe->sq_id = cpu_to_le16(fod->queue->qid);
2481 		cqe->command_id = sqe->command_id;
2482 		cqe->status = cpu_to_le16(status);
2483 	} else {
2484 
2485 		/*
2486 		 * try to push the data even if the SQE status is non-zero.
2487 		 * There may be a status where data still was intended to
2488 		 * be moved
2489 		 */
2490 		if ((fod->io_dir == NVMET_FCP_READ) && (fod->data_sg_cnt)) {
2491 			/* push the data over before sending rsp */
2492 			nvmet_fc_transfer_fcp_data(tgtport, fod,
2493 						NVMET_FCOP_READDATA);
2494 			return;
2495 		}
2496 
2497 		/* writes & no data - fall thru */
2498 	}
2499 
2500 	/* data no longer needed */
2501 	nvmet_fc_free_tgt_pgs(fod);
2502 
2503 	nvmet_fc_xmt_fcp_rsp(tgtport, fod);
2504 }
2505 
2506 
2507 static void
2508 nvmet_fc_fcp_nvme_cmd_done(struct nvmet_req *nvme_req)
2509 {
2510 	struct nvmet_fc_fcp_iod *fod = nvmet_req_to_fod(nvme_req);
2511 	struct nvmet_fc_tgtport *tgtport = fod->tgtport;
2512 
2513 	__nvmet_fc_fcp_nvme_cmd_done(tgtport, fod, 0);
2514 }
2515 
2516 
2517 /*
2518  * Actual processing routine for received FC-NVME I/O Requests from the LLD
2519  */
2520 static void
2521 nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
2522 			struct nvmet_fc_fcp_iod *fod)
2523 {
2524 	struct nvme_fc_cmd_iu *cmdiu = &fod->cmdiubuf;
2525 	u32 xfrlen = be32_to_cpu(cmdiu->data_len);
2526 	int ret;
2527 
2528 	/*
2529 	 * Fused commands are currently not supported in the linux
2530 	 * implementation.
2531 	 *
2532 	 * As such, the implementation of the FC transport does not
2533 	 * look at the fused commands and order delivery to the upper
2534 	 * layer until we have both based on csn.
2535 	 */
2536 
2537 	fod->fcpreq->done = nvmet_fc_xmt_fcp_op_done;
2538 
2539 	if (cmdiu->flags & FCNVME_CMD_FLAGS_WRITE) {
2540 		fod->io_dir = NVMET_FCP_WRITE;
2541 		if (!nvme_is_write(&cmdiu->sqe))
2542 			goto transport_error;
2543 	} else if (cmdiu->flags & FCNVME_CMD_FLAGS_READ) {
2544 		fod->io_dir = NVMET_FCP_READ;
2545 		if (nvme_is_write(&cmdiu->sqe))
2546 			goto transport_error;
2547 	} else {
2548 		fod->io_dir = NVMET_FCP_NODATA;
2549 		if (xfrlen)
2550 			goto transport_error;
2551 	}
2552 
2553 	fod->req.cmd = &fod->cmdiubuf.sqe;
2554 	fod->req.cqe = &fod->rspiubuf.cqe;
2555 	if (!tgtport->pe)
2556 		goto transport_error;
2557 	fod->req.port = tgtport->pe->port;
2558 
2559 	/* clear any response payload */
2560 	memset(&fod->rspiubuf, 0, sizeof(fod->rspiubuf));
2561 
2562 	fod->data_sg = NULL;
2563 	fod->data_sg_cnt = 0;
2564 
2565 	ret = nvmet_req_init(&fod->req,
2566 				&fod->queue->nvme_cq,
2567 				&fod->queue->nvme_sq,
2568 				&nvmet_fc_tgt_fcp_ops);
2569 	if (!ret) {
2570 		/* bad SQE content or invalid ctrl state */
2571 		/* nvmet layer has already called op done to send rsp. */
2572 		return;
2573 	}
2574 
2575 	fod->req.transfer_len = xfrlen;
2576 
2577 	/* keep a running counter of tail position */
2578 	atomic_inc(&fod->queue->sqtail);
2579 
2580 	if (fod->req.transfer_len) {
2581 		ret = nvmet_fc_alloc_tgt_pgs(fod);
2582 		if (ret) {
2583 			nvmet_req_complete(&fod->req, ret);
2584 			return;
2585 		}
2586 	}
2587 	fod->req.sg = fod->data_sg;
2588 	fod->req.sg_cnt = fod->data_sg_cnt;
2589 	fod->offset = 0;
2590 
2591 	if (fod->io_dir == NVMET_FCP_WRITE) {
2592 		/* pull the data over before invoking nvmet layer */
2593 		nvmet_fc_transfer_fcp_data(tgtport, fod, NVMET_FCOP_WRITEDATA);
2594 		return;
2595 	}
2596 
2597 	/*
2598 	 * Reads or no data:
2599 	 *
2600 	 * can invoke the nvmet_layer now. If read data, cmd completion will
2601 	 * push the data
2602 	 */
2603 	fod->req.execute(&fod->req);
2604 	return;
2605 
2606 transport_error:
2607 	nvmet_fc_abort_op(tgtport, fod);
2608 }
2609 
2610 /**
2611  * nvmet_fc_rcv_fcp_req - transport entry point called by an LLDD
2612  *                       upon the reception of a NVME FCP CMD IU.
2613  *
2614  * Pass a FC-NVME FCP CMD IU received from the FC link to the nvmet-fc
2615  * layer for processing.
2616  *
2617  * The nvmet_fc layer allocates a local job structure (struct
2618  * nvmet_fc_fcp_iod) from the queue for the io and copies the
2619  * CMD IU buffer to the job structure. As such, on a successful
2620  * completion (returns 0), the LLDD may immediately free/reuse
2621  * the CMD IU buffer passed in the call.
2622  *
2623  * However, in some circumstances, due to the packetized nature of FC
2624  * and the api of the FC LLDD which may issue a hw command to send the
2625  * response, but the LLDD may not get the hw completion for that command
2626  * and upcall the nvmet_fc layer before a new command may be
2627  * asynchronously received - its possible for a command to be received
2628  * before the LLDD and nvmet_fc have recycled the job structure. It gives
2629  * the appearance of more commands received than fits in the sq.
2630  * To alleviate this scenario, a temporary queue is maintained in the
2631  * transport for pending LLDD requests waiting for a queue job structure.
2632  * In these "overrun" cases, a temporary queue element is allocated
2633  * the LLDD request and CMD iu buffer information remembered, and the
2634  * routine returns a -EOVERFLOW status. Subsequently, when a queue job
2635  * structure is freed, it is immediately reallocated for anything on the
2636  * pending request list. The LLDDs defer_rcv() callback is called,
2637  * informing the LLDD that it may reuse the CMD IU buffer, and the io
2638  * is then started normally with the transport.
2639  *
2640  * The LLDD, when receiving an -EOVERFLOW completion status, is to treat
2641  * the completion as successful but must not reuse the CMD IU buffer
2642  * until the LLDD's defer_rcv() callback has been called for the
2643  * corresponding struct nvmefc_tgt_fcp_req pointer.
2644  *
2645  * If there is any other condition in which an error occurs, the
2646  * transport will return a non-zero status indicating the error.
2647  * In all cases other than -EOVERFLOW, the transport has not accepted the
2648  * request and the LLDD should abort the exchange.
2649  *
2650  * @target_port: pointer to the (registered) target port the FCP CMD IU
2651  *              was received on.
2652  * @fcpreq:     pointer to a fcpreq request structure to be used to reference
2653  *              the exchange corresponding to the FCP Exchange.
2654  * @cmdiubuf:   pointer to the buffer containing the FCP CMD IU
2655  * @cmdiubuf_len: length, in bytes, of the received FCP CMD IU
2656  */
2657 int
2658 nvmet_fc_rcv_fcp_req(struct nvmet_fc_target_port *target_port,
2659 			struct nvmefc_tgt_fcp_req *fcpreq,
2660 			void *cmdiubuf, u32 cmdiubuf_len)
2661 {
2662 	struct nvmet_fc_tgtport *tgtport = targetport_to_tgtport(target_port);
2663 	struct nvme_fc_cmd_iu *cmdiu = cmdiubuf;
2664 	struct nvmet_fc_tgt_queue *queue;
2665 	struct nvmet_fc_fcp_iod *fod;
2666 	struct nvmet_fc_defer_fcp_req *deferfcp;
2667 	unsigned long flags;
2668 
2669 	/* validate iu, so the connection id can be used to find the queue */
2670 	if ((cmdiubuf_len != sizeof(*cmdiu)) ||
2671 			(cmdiu->format_id != NVME_CMD_FORMAT_ID) ||
2672 			(cmdiu->fc_id != NVME_CMD_FC_ID) ||
2673 			(be16_to_cpu(cmdiu->iu_len) != (sizeof(*cmdiu)/4)))
2674 		return -EIO;
2675 
2676 	queue = nvmet_fc_find_target_queue(tgtport,
2677 				be64_to_cpu(cmdiu->connection_id));
2678 	if (!queue)
2679 		return -ENOTCONN;
2680 
2681 	/*
2682 	 * note: reference taken by find_target_queue
2683 	 * After successful fod allocation, the fod will inherit the
2684 	 * ownership of that reference and will remove the reference
2685 	 * when the fod is freed.
2686 	 */
2687 
2688 	spin_lock_irqsave(&queue->qlock, flags);
2689 
2690 	fod = nvmet_fc_alloc_fcp_iod(queue);
2691 	if (fod) {
2692 		spin_unlock_irqrestore(&queue->qlock, flags);
2693 
2694 		fcpreq->nvmet_fc_private = fod;
2695 		fod->fcpreq = fcpreq;
2696 
2697 		memcpy(&fod->cmdiubuf, cmdiubuf, cmdiubuf_len);
2698 
2699 		nvmet_fc_queue_fcp_req(tgtport, queue, fcpreq);
2700 
2701 		return 0;
2702 	}
2703 
2704 	if (!tgtport->ops->defer_rcv) {
2705 		spin_unlock_irqrestore(&queue->qlock, flags);
2706 		/* release the queue lookup reference */
2707 		nvmet_fc_tgt_q_put(queue);
2708 		return -ENOENT;
2709 	}
2710 
2711 	deferfcp = list_first_entry_or_null(&queue->avail_defer_list,
2712 			struct nvmet_fc_defer_fcp_req, req_list);
2713 	if (deferfcp) {
2714 		/* Just re-use one that was previously allocated */
2715 		list_del(&deferfcp->req_list);
2716 	} else {
2717 		spin_unlock_irqrestore(&queue->qlock, flags);
2718 
2719 		/* Now we need to dynamically allocate one */
2720 		deferfcp = kmalloc(sizeof(*deferfcp), GFP_KERNEL);
2721 		if (!deferfcp) {
2722 			/* release the queue lookup reference */
2723 			nvmet_fc_tgt_q_put(queue);
2724 			return -ENOMEM;
2725 		}
2726 		spin_lock_irqsave(&queue->qlock, flags);
2727 	}
2728 
2729 	/* For now, use rspaddr / rsplen to save payload information */
2730 	fcpreq->rspaddr = cmdiubuf;
2731 	fcpreq->rsplen  = cmdiubuf_len;
2732 	deferfcp->fcp_req = fcpreq;
2733 
2734 	/* defer processing till a fod becomes available */
2735 	list_add_tail(&deferfcp->req_list, &queue->pending_cmd_list);
2736 
2737 	/* NOTE: the queue lookup reference is still valid */
2738 
2739 	spin_unlock_irqrestore(&queue->qlock, flags);
2740 
2741 	return -EOVERFLOW;
2742 }
2743 EXPORT_SYMBOL_GPL(nvmet_fc_rcv_fcp_req);
2744 
2745 /**
2746  * nvmet_fc_rcv_fcp_abort - transport entry point called by an LLDD
2747  *                       upon the reception of an ABTS for a FCP command
2748  *
2749  * Notify the transport that an ABTS has been received for a FCP command
2750  * that had been given to the transport via nvmet_fc_rcv_fcp_req(). The
2751  * LLDD believes the command is still being worked on
2752  * (template_ops->fcp_req_release() has not been called).
2753  *
2754  * The transport will wait for any outstanding work (an op to the LLDD,
2755  * which the lldd should complete with error due to the ABTS; or the
2756  * completion from the nvmet layer of the nvme command), then will
2757  * stop processing and call the nvmet_fc_rcv_fcp_req() callback to
2758  * return the i/o context to the LLDD.  The LLDD may send the BA_ACC
2759  * to the ABTS either after return from this function (assuming any
2760  * outstanding op work has been terminated) or upon the callback being
2761  * called.
2762  *
2763  * @target_port: pointer to the (registered) target port the FCP CMD IU
2764  *              was received on.
2765  * @fcpreq:     pointer to the fcpreq request structure that corresponds
2766  *              to the exchange that received the ABTS.
2767  */
2768 void
2769 nvmet_fc_rcv_fcp_abort(struct nvmet_fc_target_port *target_port,
2770 			struct nvmefc_tgt_fcp_req *fcpreq)
2771 {
2772 	struct nvmet_fc_fcp_iod *fod = fcpreq->nvmet_fc_private;
2773 	struct nvmet_fc_tgt_queue *queue;
2774 	unsigned long flags;
2775 
2776 	if (!fod || fod->fcpreq != fcpreq)
2777 		/* job appears to have already completed, ignore abort */
2778 		return;
2779 
2780 	queue = fod->queue;
2781 
2782 	spin_lock_irqsave(&queue->qlock, flags);
2783 	if (fod->active) {
2784 		/*
2785 		 * mark as abort. The abort handler, invoked upon completion
2786 		 * of any work, will detect the aborted status and do the
2787 		 * callback.
2788 		 */
2789 		spin_lock(&fod->flock);
2790 		fod->abort = true;
2791 		fod->aborted = true;
2792 		spin_unlock(&fod->flock);
2793 	}
2794 	spin_unlock_irqrestore(&queue->qlock, flags);
2795 }
2796 EXPORT_SYMBOL_GPL(nvmet_fc_rcv_fcp_abort);
2797 
2798 
2799 struct nvmet_fc_traddr {
2800 	u64	nn;
2801 	u64	pn;
2802 };
2803 
2804 static int
2805 __nvme_fc_parse_u64(substring_t *sstr, u64 *val)
2806 {
2807 	u64 token64;
2808 
2809 	if (match_u64(sstr, &token64))
2810 		return -EINVAL;
2811 	*val = token64;
2812 
2813 	return 0;
2814 }
2815 
2816 /*
2817  * This routine validates and extracts the WWN's from the TRADDR string.
2818  * As kernel parsers need the 0x to determine number base, universally
2819  * build string to parse with 0x prefix before parsing name strings.
2820  */
2821 static int
2822 nvme_fc_parse_traddr(struct nvmet_fc_traddr *traddr, char *buf, size_t blen)
2823 {
2824 	char name[2 + NVME_FC_TRADDR_HEXNAMELEN + 1];
2825 	substring_t wwn = { name, &name[sizeof(name)-1] };
2826 	int nnoffset, pnoffset;
2827 
2828 	/* validate if string is one of the 2 allowed formats */
2829 	if (strnlen(buf, blen) == NVME_FC_TRADDR_MAXLENGTH &&
2830 			!strncmp(buf, "nn-0x", NVME_FC_TRADDR_OXNNLEN) &&
2831 			!strncmp(&buf[NVME_FC_TRADDR_MAX_PN_OFFSET],
2832 				"pn-0x", NVME_FC_TRADDR_OXNNLEN)) {
2833 		nnoffset = NVME_FC_TRADDR_OXNNLEN;
2834 		pnoffset = NVME_FC_TRADDR_MAX_PN_OFFSET +
2835 						NVME_FC_TRADDR_OXNNLEN;
2836 	} else if ((strnlen(buf, blen) == NVME_FC_TRADDR_MINLENGTH &&
2837 			!strncmp(buf, "nn-", NVME_FC_TRADDR_NNLEN) &&
2838 			!strncmp(&buf[NVME_FC_TRADDR_MIN_PN_OFFSET],
2839 				"pn-", NVME_FC_TRADDR_NNLEN))) {
2840 		nnoffset = NVME_FC_TRADDR_NNLEN;
2841 		pnoffset = NVME_FC_TRADDR_MIN_PN_OFFSET + NVME_FC_TRADDR_NNLEN;
2842 	} else
2843 		goto out_einval;
2844 
2845 	name[0] = '0';
2846 	name[1] = 'x';
2847 	name[2 + NVME_FC_TRADDR_HEXNAMELEN] = 0;
2848 
2849 	memcpy(&name[2], &buf[nnoffset], NVME_FC_TRADDR_HEXNAMELEN);
2850 	if (__nvme_fc_parse_u64(&wwn, &traddr->nn))
2851 		goto out_einval;
2852 
2853 	memcpy(&name[2], &buf[pnoffset], NVME_FC_TRADDR_HEXNAMELEN);
2854 	if (__nvme_fc_parse_u64(&wwn, &traddr->pn))
2855 		goto out_einval;
2856 
2857 	return 0;
2858 
2859 out_einval:
2860 	pr_warn("%s: bad traddr string\n", __func__);
2861 	return -EINVAL;
2862 }
2863 
2864 static int
2865 nvmet_fc_add_port(struct nvmet_port *port)
2866 {
2867 	struct nvmet_fc_tgtport *tgtport;
2868 	struct nvmet_fc_port_entry *pe;
2869 	struct nvmet_fc_traddr traddr = { 0L, 0L };
2870 	unsigned long flags;
2871 	int ret;
2872 
2873 	/* validate the address info */
2874 	if ((port->disc_addr.trtype != NVMF_TRTYPE_FC) ||
2875 	    (port->disc_addr.adrfam != NVMF_ADDR_FAMILY_FC))
2876 		return -EINVAL;
2877 
2878 	/* map the traddr address info to a target port */
2879 
2880 	ret = nvme_fc_parse_traddr(&traddr, port->disc_addr.traddr,
2881 			sizeof(port->disc_addr.traddr));
2882 	if (ret)
2883 		return ret;
2884 
2885 	pe = kzalloc(sizeof(*pe), GFP_KERNEL);
2886 	if (!pe)
2887 		return -ENOMEM;
2888 
2889 	ret = -ENXIO;
2890 	spin_lock_irqsave(&nvmet_fc_tgtlock, flags);
2891 	list_for_each_entry(tgtport, &nvmet_fc_target_list, tgt_list) {
2892 		if ((tgtport->fc_target_port.node_name == traddr.nn) &&
2893 		    (tgtport->fc_target_port.port_name == traddr.pn)) {
2894 			/* a FC port can only be 1 nvmet port id */
2895 			if (!tgtport->pe) {
2896 				nvmet_fc_portentry_bind(tgtport, pe, port);
2897 				ret = 0;
2898 			} else
2899 				ret = -EALREADY;
2900 			break;
2901 		}
2902 	}
2903 	spin_unlock_irqrestore(&nvmet_fc_tgtlock, flags);
2904 
2905 	if (ret)
2906 		kfree(pe);
2907 
2908 	return ret;
2909 }
2910 
2911 static void
2912 nvmet_fc_remove_port(struct nvmet_port *port)
2913 {
2914 	struct nvmet_fc_port_entry *pe = port->priv;
2915 
2916 	nvmet_fc_portentry_unbind(pe);
2917 
2918 	/* terminate any outstanding associations */
2919 	__nvmet_fc_free_assocs(pe->tgtport);
2920 
2921 	kfree(pe);
2922 }
2923 
2924 static void
2925 nvmet_fc_discovery_chg(struct nvmet_port *port)
2926 {
2927 	struct nvmet_fc_port_entry *pe = port->priv;
2928 	struct nvmet_fc_tgtport *tgtport = pe->tgtport;
2929 
2930 	if (tgtport && tgtport->ops->discovery_event)
2931 		tgtport->ops->discovery_event(&tgtport->fc_target_port);
2932 }
2933 
2934 static const struct nvmet_fabrics_ops nvmet_fc_tgt_fcp_ops = {
2935 	.owner			= THIS_MODULE,
2936 	.type			= NVMF_TRTYPE_FC,
2937 	.msdbd			= 1,
2938 	.add_port		= nvmet_fc_add_port,
2939 	.remove_port		= nvmet_fc_remove_port,
2940 	.queue_response		= nvmet_fc_fcp_nvme_cmd_done,
2941 	.delete_ctrl		= nvmet_fc_delete_ctrl,
2942 	.discovery_chg		= nvmet_fc_discovery_chg,
2943 };
2944 
2945 static int __init nvmet_fc_init_module(void)
2946 {
2947 	return nvmet_register_transport(&nvmet_fc_tgt_fcp_ops);
2948 }
2949 
2950 static void __exit nvmet_fc_exit_module(void)
2951 {
2952 	/* ensure any shutdown operation, e.g. delete ctrls have finished */
2953 	flush_workqueue(nvmet_wq);
2954 
2955 	/* sanity check - all lports should be removed */
2956 	if (!list_empty(&nvmet_fc_target_list))
2957 		pr_warn("%s: targetport list not empty\n", __func__);
2958 
2959 	nvmet_unregister_transport(&nvmet_fc_tgt_fcp_ops);
2960 
2961 	ida_destroy(&nvmet_fc_tgtport_cnt);
2962 }
2963 
2964 module_init(nvmet_fc_init_module);
2965 module_exit(nvmet_fc_exit_module);
2966 
2967 MODULE_DESCRIPTION("NVMe target FC transport driver");
2968 MODULE_LICENSE("GPL v2");
2969