fc_fcp.c revision 7b2787ec15b9d1c2f716da61b0eec21a3f5e6520
1/*
2 * Copyright(c) 2007 Intel Corporation. All rights reserved.
3 * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
4 * Copyright(c) 2008 Mike Christie
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Maintained at www.Open-FCoE.org
20 */
21
22#include <linux/module.h>
23#include <linux/delay.h>
24#include <linux/kernel.h>
25#include <linux/types.h>
26#include <linux/spinlock.h>
27#include <linux/scatterlist.h>
28#include <linux/err.h>
29#include <linux/crc32.h>
30#include <linux/slab.h>
31
32#include <scsi/scsi_tcq.h>
33#include <scsi/scsi.h>
34#include <scsi/scsi_host.h>
35#include <scsi/scsi_device.h>
36#include <scsi/scsi_cmnd.h>
37
38#include <scsi/fc/fc_fc2.h>
39
40#include <scsi/libfc.h>
41#include <scsi/fc_encode.h>
42
43#include "fc_libfc.h"
44
45struct kmem_cache *scsi_pkt_cachep;
46
47/* SRB state definitions */
48#define FC_SRB_FREE		0		/* cmd is free */
49#define FC_SRB_CMD_SENT		(1 << 0)	/* cmd has been sent */
50#define FC_SRB_RCV_STATUS	(1 << 1)	/* response has arrived */
51#define FC_SRB_ABORT_PENDING	(1 << 2)	/* cmd abort sent to device */
52#define FC_SRB_ABORTED		(1 << 3)	/* abort acknowledged */
53#define FC_SRB_DISCONTIG	(1 << 4)	/* non-sequential data recvd */
54#define FC_SRB_COMPL		(1 << 5)	/* fc_io_compl has been run */
55#define FC_SRB_FCP_PROCESSING_TMO (1 << 6)	/* timer function processing */
56
57#define FC_SRB_READ		(1 << 1)
58#define FC_SRB_WRITE		(1 << 0)
59
60/*
61 * The SCp.ptr should be tested and set under the host lock. NULL indicates
62 * that the command has been retruned to the scsi layer.
63 */
64#define CMD_SP(Cmnd)		    ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
65#define CMD_ENTRY_STATUS(Cmnd)	    ((Cmnd)->SCp.have_data_in)
66#define CMD_COMPL_STATUS(Cmnd)	    ((Cmnd)->SCp.this_residual)
67#define CMD_SCSI_STATUS(Cmnd)	    ((Cmnd)->SCp.Status)
68#define CMD_RESID_LEN(Cmnd)	    ((Cmnd)->SCp.buffers_residual)
69
70/**
71 * struct fc_fcp_internal - FCP layer internal data
72 * @scsi_pkt_pool: Memory pool to draw FCP packets from
73 * @scsi_queue_lock: Protects the scsi_pkt_queue
74 * @scsi_pkt_queue: Current FCP packets
75 * @last_can_queue_ramp_down_time: ramp down time
76 * @last_can_queue_ramp_up_time: ramp up time
77 * @max_can_queue: max can_queue size
78 */
79struct fc_fcp_internal {
80	mempool_t		*scsi_pkt_pool;
81	spinlock_t		scsi_queue_lock;
82	struct list_head	scsi_pkt_queue;
83	unsigned long		last_can_queue_ramp_down_time;
84	unsigned long		last_can_queue_ramp_up_time;
85	int			max_can_queue;
86};
87
88#define fc_get_scsi_internal(x)	((struct fc_fcp_internal *)(x)->scsi_priv)
89
90/*
91 * function prototypes
92 * FC scsi I/O related functions
93 */
94static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
95static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
96static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
97static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
98static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
99static void fc_fcp_error(struct fc_fcp_pkt *, struct fc_frame *);
100static void fc_fcp_recovery(struct fc_fcp_pkt *);
101static void fc_fcp_timeout(unsigned long);
102static void fc_fcp_rec(struct fc_fcp_pkt *);
103static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
104static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
105static void fc_io_compl(struct fc_fcp_pkt *);
106
107static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
108static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
109static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
110
111/*
112 * command status codes
113 */
114#define FC_COMPLETE		0
115#define FC_CMD_ABORTED		1
116#define FC_CMD_RESET		2
117#define FC_CMD_PLOGO		3
118#define FC_SNS_RCV		4
119#define FC_TRANS_ERR		5
120#define FC_DATA_OVRRUN		6
121#define FC_DATA_UNDRUN		7
122#define FC_ERROR		8
123#define FC_HRD_ERROR		9
124#define FC_CMD_RECOVERY		10
125
126/*
127 * Error recovery timeout values.
128 */
129#define FC_SCSI_ER_TIMEOUT	(10 * HZ)
130#define FC_SCSI_TM_TOV		(10 * HZ)
131#define FC_SCSI_REC_TOV		(2 * HZ)
132#define FC_HOST_RESET_TIMEOUT	(30 * HZ)
133#define FC_CAN_QUEUE_PERIOD	(60 * HZ)
134
135#define FC_MAX_ERROR_CNT	5
136#define FC_MAX_RECOV_RETRY	3
137
138#define FC_FCP_DFLT_QUEUE_DEPTH 32
139
140/**
141 * fc_fcp_pkt_alloc() - Allocate a fcp_pkt
142 * @lport: The local port that the FCP packet is for
143 * @gfp:   GFP flags for allocation
144 *
145 * Return value: fcp_pkt structure or null on allocation failure.
146 * Context:	 Can be called from process context, no lock is required.
147 */
148static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp)
149{
150	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
151	struct fc_fcp_pkt *fsp;
152
153	fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
154	if (fsp) {
155		memset(fsp, 0, sizeof(*fsp));
156		fsp->lp = lport;
157		atomic_set(&fsp->ref_cnt, 1);
158		init_timer(&fsp->timer);
159		INIT_LIST_HEAD(&fsp->list);
160		spin_lock_init(&fsp->scsi_pkt_lock);
161	}
162	return fsp;
163}
164
165/**
166 * fc_fcp_pkt_release() - Release hold on a fcp_pkt
167 * @fsp: The FCP packet to be released
168 *
169 * Context: Can be called from process or interrupt context,
170 *	    no lock is required.
171 */
172static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
173{
174	if (atomic_dec_and_test(&fsp->ref_cnt)) {
175		struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
176
177		mempool_free(fsp, si->scsi_pkt_pool);
178	}
179}
180
181/**
182 * fc_fcp_pkt_hold() - Hold a fcp_pkt
183 * @fsp: The FCP packet to be held
184 */
185static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
186{
187	atomic_inc(&fsp->ref_cnt);
188}
189
190/**
191 * fc_fcp_pkt_destory() - Release hold on a fcp_pkt
192 * @seq: The sequence that the FCP packet is on (required by destructor API)
193 * @fsp: The FCP packet to be released
194 *
195 * This routine is called by a destructor callback in the exch_seq_send()
196 * routine of the libfc Transport Template. The 'struct fc_seq' is a required
197 * argument even though it is not used by this routine.
198 *
199 * Context: No locking required.
200 */
201static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
202{
203	fc_fcp_pkt_release(fsp);
204}
205
206/**
207 * fc_fcp_lock_pkt() - Lock a fcp_pkt and increase its reference count
208 * @fsp: The FCP packet to be locked and incremented
209 *
210 * We should only return error if we return a command to SCSI-ml before
211 * getting a response. This can happen in cases where we send a abort, but
212 * do not wait for the response and the abort and command can be passing
213 * each other on the wire/network-layer.
214 *
215 * Note: this function locks the packet and gets a reference to allow
216 * callers to call the completion function while the lock is held and
217 * not have to worry about the packets refcount.
218 *
219 * TODO: Maybe we should just have callers grab/release the lock and
220 * have a function that they call to verify the fsp and grab a ref if
221 * needed.
222 */
223static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
224{
225	spin_lock_bh(&fsp->scsi_pkt_lock);
226	if (fsp->state & FC_SRB_COMPL) {
227		spin_unlock_bh(&fsp->scsi_pkt_lock);
228		return -EPERM;
229	}
230
231	fc_fcp_pkt_hold(fsp);
232	return 0;
233}
234
235/**
236 * fc_fcp_unlock_pkt() - Release a fcp_pkt's lock and decrement its
237 *			 reference count
238 * @fsp: The FCP packet to be unlocked and decremented
239 */
240static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
241{
242	spin_unlock_bh(&fsp->scsi_pkt_lock);
243	fc_fcp_pkt_release(fsp);
244}
245
246/**
247 * fc_fcp_timer_set() - Start a timer for a fcp_pkt
248 * @fsp:   The FCP packet to start a timer for
249 * @delay: The timeout period for the timer
250 */
251static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
252{
253	if (!(fsp->state & FC_SRB_COMPL))
254		mod_timer(&fsp->timer, jiffies + delay);
255}
256
257/**
258 * fc_fcp_send_abort() - Send an abort for exchanges associated with a
259 *			 fcp_pkt
260 * @fsp: The FCP packet to abort exchanges on
261 */
262static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
263{
264	if (!fsp->seq_ptr)
265		return -EINVAL;
266
267	fsp->state |= FC_SRB_ABORT_PENDING;
268	return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
269}
270
271/**
272 * fc_fcp_retry_cmd() - Retry a fcp_pkt
273 * @fsp: The FCP packet to be retried
274 *
275 * Sets the status code to be FC_ERROR and then calls
276 * fc_fcp_complete_locked() which in turn calls fc_io_compl().
277 * fc_io_compl() will notify the SCSI-ml that the I/O is done.
278 * The SCSI-ml will retry the command.
279 */
280static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
281{
282	if (fsp->seq_ptr) {
283		fsp->lp->tt.exch_done(fsp->seq_ptr);
284		fsp->seq_ptr = NULL;
285	}
286
287	fsp->state &= ~FC_SRB_ABORT_PENDING;
288	fsp->io_status = 0;
289	fsp->status_code = FC_ERROR;
290	fc_fcp_complete_locked(fsp);
291}
292
293/**
294 * fc_fcp_ddp_setup() - Calls a LLD's ddp_setup routine to set up DDP context
295 * @fsp: The FCP packet that will manage the DDP frames
296 * @xid: The XID that will be used for the DDP exchange
297 */
298void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
299{
300	struct fc_lport *lport;
301
302	lport = fsp->lp;
303	if ((fsp->req_flags & FC_SRB_READ) &&
304	    (lport->lro_enabled) && (lport->tt.ddp_setup)) {
305		if (lport->tt.ddp_setup(lport, xid, scsi_sglist(fsp->cmd),
306					scsi_sg_count(fsp->cmd)))
307			fsp->xfer_ddp = xid;
308	}
309}
310
311/**
312 * fc_fcp_ddp_done() - Calls a LLD's ddp_done routine to release any
313 *		       DDP related resources for a fcp_pkt
314 * @fsp: The FCP packet that DDP had been used on
315 */
316static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
317{
318	struct fc_lport *lport;
319
320	if (!fsp)
321		return;
322
323	if (fsp->xfer_ddp == FC_XID_UNKNOWN)
324		return;
325
326	lport = fsp->lp;
327	if (lport->tt.ddp_done) {
328		fsp->xfer_len = lport->tt.ddp_done(lport, fsp->xfer_ddp);
329		fsp->xfer_ddp = FC_XID_UNKNOWN;
330	}
331}
332
333/**
334 * fc_fcp_can_queue_ramp_up() - increases can_queue
335 * @lport: lport to ramp up can_queue
336 *
337 * Locking notes: Called with Scsi_Host lock held
338 */
339static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport)
340{
341	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
342	int can_queue;
343
344	if (si->last_can_queue_ramp_up_time &&
345	    (time_before(jiffies, si->last_can_queue_ramp_up_time +
346			 FC_CAN_QUEUE_PERIOD)))
347		return;
348
349	if (time_before(jiffies, si->last_can_queue_ramp_down_time +
350			FC_CAN_QUEUE_PERIOD))
351		return;
352
353	si->last_can_queue_ramp_up_time = jiffies;
354
355	can_queue = lport->host->can_queue << 1;
356	if (can_queue >= si->max_can_queue) {
357		can_queue = si->max_can_queue;
358		si->last_can_queue_ramp_down_time = 0;
359	}
360	lport->host->can_queue = can_queue;
361	shost_printk(KERN_ERR, lport->host, "libfc: increased "
362		     "can_queue to %d.\n", can_queue);
363}
364
365/**
366 * fc_fcp_can_queue_ramp_down() - reduces can_queue
367 * @lport: lport to reduce can_queue
368 *
369 * If we are getting memory allocation failures, then we may
370 * be trying to execute too many commands. We let the running
371 * commands complete or timeout, then try again with a reduced
372 * can_queue. Eventually we will hit the point where we run
373 * on all reserved structs.
374 *
375 * Locking notes: Called with Scsi_Host lock held
376 */
377static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport)
378{
379	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
380	int can_queue;
381
382	if (si->last_can_queue_ramp_down_time &&
383	    (time_before(jiffies, si->last_can_queue_ramp_down_time +
384			 FC_CAN_QUEUE_PERIOD)))
385		return;
386
387	si->last_can_queue_ramp_down_time = jiffies;
388
389	can_queue = lport->host->can_queue;
390	can_queue >>= 1;
391	if (!can_queue)
392		can_queue = 1;
393	lport->host->can_queue = can_queue;
394	shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n"
395		     "Reducing can_queue to %d.\n", can_queue);
396}
397
398/*
399 * fc_fcp_frame_alloc() -  Allocates fc_frame structure and buffer.
400 * @lport:	fc lport struct
401 * @len:	payload length
402 *
403 * Allocates fc_frame structure and buffer but if fails to allocate
404 * then reduce can_queue.
405 */
406static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport,
407						  size_t len)
408{
409	struct fc_frame *fp;
410	unsigned long flags;
411
412	fp = fc_frame_alloc(lport, len);
413	if (likely(fp))
414		return fp;
415
416	/* error case */
417	spin_lock_irqsave(lport->host->host_lock, flags);
418	fc_fcp_can_queue_ramp_down(lport);
419	spin_unlock_irqrestore(lport->host->host_lock, flags);
420	return NULL;
421}
422
423/**
424 * fc_fcp_recv_data() - Handler for receiving SCSI-FCP data from a target
425 * @fsp: The FCP packet the data is on
426 * @fp:	 The data frame
427 */
428static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
429{
430	struct scsi_cmnd *sc = fsp->cmd;
431	struct fc_lport *lport = fsp->lp;
432	struct fcoe_dev_stats *stats;
433	struct fc_frame_header *fh;
434	size_t start_offset;
435	size_t offset;
436	u32 crc;
437	u32 copy_len = 0;
438	size_t len;
439	void *buf;
440	struct scatterlist *sg;
441	u32 nents;
442
443	fh = fc_frame_header_get(fp);
444	offset = ntohl(fh->fh_parm_offset);
445	start_offset = offset;
446	len = fr_len(fp) - sizeof(*fh);
447	buf = fc_frame_payload_get(fp, 0);
448
449	/*
450	 * if this I/O is ddped then clear it
451	 * and initiate recovery since data
452	 * frames are expected to be placed
453	 * directly in that case.
454	 */
455	if (fsp->xfer_ddp != FC_XID_UNKNOWN) {
456		fc_fcp_ddp_done(fsp);
457		goto err;
458	}
459	if (offset + len > fsp->data_len) {
460		/* this should never happen */
461		if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
462		    fc_frame_crc_check(fp))
463			goto crc_err;
464		FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
465			   "data_len %x\n", len, offset, fsp->data_len);
466		goto err;
467	}
468	if (offset != fsp->xfer_len)
469		fsp->state |= FC_SRB_DISCONTIG;
470
471	sg = scsi_sglist(sc);
472	nents = scsi_sg_count(sc);
473
474	if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) {
475		copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
476						    &offset, KM_SOFTIRQ0, NULL);
477	} else {
478		crc = crc32(~0, (u8 *) fh, sizeof(*fh));
479		copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
480						    &offset, KM_SOFTIRQ0, &crc);
481		buf = fc_frame_payload_get(fp, 0);
482		if (len % 4)
483			crc = crc32(crc, buf + len, 4 - (len % 4));
484
485		if (~crc != le32_to_cpu(fr_crc(fp))) {
486crc_err:
487			stats = per_cpu_ptr(lport->dev_stats, get_cpu());
488			stats->ErrorFrames++;
489			/* per cpu count, not total count, but OK for limit */
490			if (stats->InvalidCRCCount++ < 5)
491				printk(KERN_WARNING "libfc: CRC error on data "
492				       "frame for port (%6.6x)\n",
493				       lport->port_id);
494			put_cpu();
495			/*
496			 * Assume the frame is total garbage.
497			 * We may have copied it over the good part
498			 * of the buffer.
499			 * If so, we need to retry the entire operation.
500			 * Otherwise, ignore it.
501			 */
502			if (fsp->state & FC_SRB_DISCONTIG)
503				goto err;
504			return;
505		}
506	}
507
508	if (fsp->xfer_contig_end == start_offset)
509		fsp->xfer_contig_end += copy_len;
510	fsp->xfer_len += copy_len;
511
512	/*
513	 * In the very rare event that this data arrived after the response
514	 * and completes the transfer, call the completion handler.
515	 */
516	if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
517	    fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
518		fc_fcp_complete_locked(fsp);
519	return;
520err:
521	fc_fcp_recovery(fsp);
522}
523
524/**
525 * fc_fcp_send_data() - Send SCSI data to a target
526 * @fsp:      The FCP packet the data is on
527 * @sp:	      The sequence the data is to be sent on
528 * @offset:   The starting offset for this data request
529 * @seq_blen: The burst length for this data request
530 *
531 * Called after receiving a Transfer Ready data descriptor.
532 * If the LLD is capable of sequence offload then send down the
533 * seq_blen amount of data in single frame, otherwise send
534 * multiple frames of the maximum frame payload supported by
535 * the target port.
536 */
537static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
538			    size_t offset, size_t seq_blen)
539{
540	struct fc_exch *ep;
541	struct scsi_cmnd *sc;
542	struct scatterlist *sg;
543	struct fc_frame *fp = NULL;
544	struct fc_lport *lport = fsp->lp;
545	struct page *page;
546	size_t remaining;
547	size_t t_blen;
548	size_t tlen;
549	size_t sg_bytes;
550	size_t frame_offset, fh_parm_offset;
551	size_t off;
552	int error;
553	void *data = NULL;
554	void *page_addr;
555	int using_sg = lport->sg_supp;
556	u32 f_ctl;
557
558	WARN_ON(seq_blen <= 0);
559	if (unlikely(offset + seq_blen > fsp->data_len)) {
560		/* this should never happen */
561		FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
562			   "offset %zx\n", seq_blen, offset);
563		fc_fcp_send_abort(fsp);
564		return 0;
565	} else if (offset != fsp->xfer_len) {
566		/* Out of Order Data Request - no problem, but unexpected. */
567		FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
568			   "seq_blen %zx offset %zx\n", seq_blen, offset);
569	}
570
571	/*
572	 * if LLD is capable of seq_offload then set transport
573	 * burst length (t_blen) to seq_blen, otherwise set t_blen
574	 * to max FC frame payload previously set in fsp->max_payload.
575	 */
576	t_blen = fsp->max_payload;
577	if (lport->seq_offload) {
578		t_blen = min(seq_blen, (size_t)lport->lso_max);
579		FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
580			   fsp, seq_blen, lport->lso_max, t_blen);
581	}
582
583	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
584	if (t_blen > 512)
585		t_blen &= ~(512 - 1);	/* round down to block size */
586	WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);	/* won't go below 256 */
587	sc = fsp->cmd;
588
589	remaining = seq_blen;
590	fh_parm_offset = frame_offset = offset;
591	tlen = 0;
592	seq = lport->tt.seq_start_next(seq);
593	f_ctl = FC_FC_REL_OFF;
594	WARN_ON(!seq);
595
596	sg = scsi_sglist(sc);
597
598	while (remaining > 0 && sg) {
599		if (offset >= sg->length) {
600			offset -= sg->length;
601			sg = sg_next(sg);
602			continue;
603		}
604		if (!fp) {
605			tlen = min(t_blen, remaining);
606
607			/*
608			 * TODO.  Temporary workaround.	 fc_seq_send() can't
609			 * handle odd lengths in non-linear skbs.
610			 * This will be the final fragment only.
611			 */
612			if (tlen % 4)
613				using_sg = 0;
614			fp = fc_frame_alloc(lport, using_sg ? 0 : tlen);
615			if (!fp)
616				return -ENOMEM;
617
618			data = fc_frame_header_get(fp) + 1;
619			fh_parm_offset = frame_offset;
620			fr_max_payload(fp) = fsp->max_payload;
621		}
622
623		off = offset + sg->offset;
624		sg_bytes = min(tlen, sg->length - offset);
625		sg_bytes = min(sg_bytes,
626			       (size_t) (PAGE_SIZE - (off & ~PAGE_MASK)));
627		page = sg_page(sg) + (off >> PAGE_SHIFT);
628		if (using_sg) {
629			get_page(page);
630			skb_fill_page_desc(fp_skb(fp),
631					   skb_shinfo(fp_skb(fp))->nr_frags,
632					   page, off & ~PAGE_MASK, sg_bytes);
633			fp_skb(fp)->data_len += sg_bytes;
634			fr_len(fp) += sg_bytes;
635			fp_skb(fp)->truesize += PAGE_SIZE;
636		} else {
637			/*
638			 * The scatterlist item may be bigger than PAGE_SIZE,
639			 * but we must not cross pages inside the kmap.
640			 */
641			page_addr = kmap_atomic(page, KM_SOFTIRQ0);
642			memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
643			       sg_bytes);
644			kunmap_atomic(page_addr, KM_SOFTIRQ0);
645			data += sg_bytes;
646		}
647		offset += sg_bytes;
648		frame_offset += sg_bytes;
649		tlen -= sg_bytes;
650		remaining -= sg_bytes;
651
652		if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
653		    (tlen))
654			continue;
655
656		/*
657		 * Send sequence with transfer sequence initiative in case
658		 * this is last FCP frame of the sequence.
659		 */
660		if (remaining == 0)
661			f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
662
663		ep = fc_seq_exch(seq);
664		fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
665			       FC_TYPE_FCP, f_ctl, fh_parm_offset);
666
667		/*
668		 * send fragment using for a sequence.
669		 */
670		error = lport->tt.seq_send(lport, seq, fp);
671		if (error) {
672			WARN_ON(1);		/* send error should be rare */
673			fc_fcp_retry_cmd(fsp);
674			return 0;
675		}
676		fp = NULL;
677	}
678	fsp->xfer_len += seq_blen;	/* premature count? */
679	return 0;
680}
681
682/**
683 * fc_fcp_abts_resp() - Send an ABTS response
684 * @fsp: The FCP packet that is being aborted
685 * @fp:	 The response frame
686 */
687static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
688{
689	int ba_done = 1;
690	struct fc_ba_rjt *brp;
691	struct fc_frame_header *fh;
692
693	fh = fc_frame_header_get(fp);
694	switch (fh->fh_r_ctl) {
695	case FC_RCTL_BA_ACC:
696		break;
697	case FC_RCTL_BA_RJT:
698		brp = fc_frame_payload_get(fp, sizeof(*brp));
699		if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
700			break;
701		/* fall thru */
702	default:
703		/*
704		 * we will let the command timeout
705		 * and scsi-ml recover in this case,
706		 * therefore cleared the ba_done flag.
707		 */
708		ba_done = 0;
709	}
710
711	if (ba_done) {
712		fsp->state |= FC_SRB_ABORTED;
713		fsp->state &= ~FC_SRB_ABORT_PENDING;
714
715		if (fsp->wait_for_comp)
716			complete(&fsp->tm_done);
717		else
718			fc_fcp_complete_locked(fsp);
719	}
720}
721
722/**
723 * fc_fcp_recv() - Reveive an FCP frame
724 * @seq: The sequence the frame is on
725 * @fp:	 The received frame
726 * @arg: The related FCP packet
727 *
728 * Context: Called from Soft IRQ context. Can not be called
729 *	    holding the FCP packet list lock.
730 */
731static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
732{
733	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
734	struct fc_lport *lport = fsp->lp;
735	struct fc_frame_header *fh;
736	struct fcp_txrdy *dd;
737	u8 r_ctl;
738	int rc = 0;
739
740	if (IS_ERR(fp)) {
741		fc_fcp_error(fsp, fp);
742		return;
743	}
744
745	fh = fc_frame_header_get(fp);
746	r_ctl = fh->fh_r_ctl;
747
748	if (!(lport->state & LPORT_ST_READY))
749		goto out;
750	if (fc_fcp_lock_pkt(fsp))
751		goto out;
752	fsp->last_pkt_time = jiffies;
753
754	if (fh->fh_type == FC_TYPE_BLS) {
755		fc_fcp_abts_resp(fsp, fp);
756		goto unlock;
757	}
758
759	if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
760		goto unlock;
761
762	if (r_ctl == FC_RCTL_DD_DATA_DESC) {
763		/*
764		 * received XFER RDY from the target
765		 * need to send data to the target
766		 */
767		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
768		dd = fc_frame_payload_get(fp, sizeof(*dd));
769		WARN_ON(!dd);
770
771		rc = fc_fcp_send_data(fsp, seq,
772				      (size_t) ntohl(dd->ft_data_ro),
773				      (size_t) ntohl(dd->ft_burst_len));
774		if (!rc)
775			seq->rec_data = fsp->xfer_len;
776	} else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
777		/*
778		 * received a DATA frame
779		 * next we will copy the data to the system buffer
780		 */
781		WARN_ON(fr_len(fp) < sizeof(*fh));	/* len may be 0 */
782		fc_fcp_recv_data(fsp, fp);
783		seq->rec_data = fsp->xfer_contig_end;
784	} else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
785		WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
786
787		fc_fcp_resp(fsp, fp);
788	} else {
789		FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
790	}
791unlock:
792	fc_fcp_unlock_pkt(fsp);
793out:
794	fc_frame_free(fp);
795}
796
797/**
798 * fc_fcp_resp() - Handler for FCP responses
799 * @fsp: The FCP packet the response is for
800 * @fp:	 The response frame
801 */
802static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
803{
804	struct fc_frame_header *fh;
805	struct fcp_resp *fc_rp;
806	struct fcp_resp_ext *rp_ex;
807	struct fcp_resp_rsp_info *fc_rp_info;
808	u32 plen;
809	u32 expected_len;
810	u32 respl = 0;
811	u32 snsl = 0;
812	u8 flags = 0;
813
814	plen = fr_len(fp);
815	fh = (struct fc_frame_header *)fr_hdr(fp);
816	if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
817		goto len_err;
818	plen -= sizeof(*fh);
819	fc_rp = (struct fcp_resp *)(fh + 1);
820	fsp->cdb_status = fc_rp->fr_status;
821	flags = fc_rp->fr_flags;
822	fsp->scsi_comp_flags = flags;
823	expected_len = fsp->data_len;
824
825	/* if ddp, update xfer len */
826	fc_fcp_ddp_done(fsp);
827
828	if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
829		rp_ex = (void *)(fc_rp + 1);
830		if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
831			if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
832				goto len_err;
833			fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
834			if (flags & FCP_RSP_LEN_VAL) {
835				respl = ntohl(rp_ex->fr_rsp_len);
836				if (respl != sizeof(*fc_rp_info))
837					goto len_err;
838				if (fsp->wait_for_comp) {
839					/* Abuse cdb_status for rsp code */
840					fsp->cdb_status = fc_rp_info->rsp_code;
841					complete(&fsp->tm_done);
842					/*
843					 * tmfs will not have any scsi cmd so
844					 * exit here
845					 */
846					return;
847				}
848			}
849			if (flags & FCP_SNS_LEN_VAL) {
850				snsl = ntohl(rp_ex->fr_sns_len);
851				if (snsl > SCSI_SENSE_BUFFERSIZE)
852					snsl = SCSI_SENSE_BUFFERSIZE;
853				memcpy(fsp->cmd->sense_buffer,
854				       (char *)fc_rp_info + respl, snsl);
855			}
856		}
857		if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
858			if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
859				goto len_err;
860			if (flags & FCP_RESID_UNDER) {
861				fsp->scsi_resid = ntohl(rp_ex->fr_resid);
862				/*
863				 * The cmnd->underflow is the minimum number of
864				 * bytes that must be transfered for this
865				 * command.  Provided a sense condition is not
866				 * present, make sure the actual amount
867				 * transferred is at least the underflow value
868				 * or fail.
869				 */
870				if (!(flags & FCP_SNS_LEN_VAL) &&
871				    (fc_rp->fr_status == 0) &&
872				    (scsi_bufflen(fsp->cmd) -
873				     fsp->scsi_resid) < fsp->cmd->underflow)
874					goto err;
875				expected_len -= fsp->scsi_resid;
876			} else {
877				fsp->status_code = FC_ERROR;
878			}
879		}
880	}
881	fsp->state |= FC_SRB_RCV_STATUS;
882
883	/*
884	 * Check for missing or extra data frames.
885	 */
886	if (unlikely(fsp->xfer_len != expected_len)) {
887		if (fsp->xfer_len < expected_len) {
888			/*
889			 * Some data may be queued locally,
890			 * Wait a at least one jiffy to see if it is delivered.
891			 * If this expires without data, we may do SRR.
892			 */
893			fc_fcp_timer_set(fsp, 2);
894			return;
895		}
896		fsp->status_code = FC_DATA_OVRRUN;
897		FC_FCP_DBG(fsp, "tgt %6.6x xfer len %zx greater than expected, "
898			   "len %x, data len %x\n",
899			   fsp->rport->port_id,
900			   fsp->xfer_len, expected_len, fsp->data_len);
901	}
902	fc_fcp_complete_locked(fsp);
903	return;
904
905len_err:
906	FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
907		   "snsl %u\n", flags, fr_len(fp), respl, snsl);
908err:
909	fsp->status_code = FC_ERROR;
910	fc_fcp_complete_locked(fsp);
911}
912
913/**
914 * fc_fcp_complete_locked() - Complete processing of a fcp_pkt with the
915 *			      fcp_pkt lock held
916 * @fsp: The FCP packet to be completed
917 *
918 * This function may sleep if a timer is pending. The packet lock must be
919 * held, and the host lock must not be held.
920 */
921static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
922{
923	struct fc_lport *lport = fsp->lp;
924	struct fc_seq *seq;
925	struct fc_exch *ep;
926	u32 f_ctl;
927
928	if (fsp->state & FC_SRB_ABORT_PENDING)
929		return;
930
931	if (fsp->state & FC_SRB_ABORTED) {
932		if (!fsp->status_code)
933			fsp->status_code = FC_CMD_ABORTED;
934	} else {
935		/*
936		 * Test for transport underrun, independent of response
937		 * underrun status.
938		 */
939		if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
940		    (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
941		     fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
942			fsp->status_code = FC_DATA_UNDRUN;
943			fsp->io_status = 0;
944		}
945	}
946
947	seq = fsp->seq_ptr;
948	if (seq) {
949		fsp->seq_ptr = NULL;
950		if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
951			struct fc_frame *conf_frame;
952			struct fc_seq *csp;
953
954			csp = lport->tt.seq_start_next(seq);
955			conf_frame = fc_fcp_frame_alloc(fsp->lp, 0);
956			if (conf_frame) {
957				f_ctl = FC_FC_SEQ_INIT;
958				f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
959				ep = fc_seq_exch(seq);
960				fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
961					       ep->did, ep->sid,
962					       FC_TYPE_FCP, f_ctl, 0);
963				lport->tt.seq_send(lport, csp, conf_frame);
964			}
965		}
966		lport->tt.exch_done(seq);
967	}
968	fc_io_compl(fsp);
969}
970
971/**
972 * fc_fcp_cleanup_cmd() - Cancel the active exchange on a fcp_pkt
973 * @fsp:   The FCP packet whose exchanges should be canceled
974 * @error: The reason for the cancellation
975 */
976static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
977{
978	struct fc_lport *lport = fsp->lp;
979
980	if (fsp->seq_ptr) {
981		lport->tt.exch_done(fsp->seq_ptr);
982		fsp->seq_ptr = NULL;
983	}
984	fsp->status_code = error;
985}
986
987/**
988 * fc_fcp_cleanup_each_cmd() - Cancel all exchanges on a local port
989 * @lport: The local port whose exchanges should be canceled
990 * @id:	   The target's ID
991 * @lun:   The LUN
992 * @error: The reason for cancellation
993 *
994 * If lun or id is -1, they are ignored.
995 */
996static void fc_fcp_cleanup_each_cmd(struct fc_lport *lport, unsigned int id,
997				    unsigned int lun, int error)
998{
999	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1000	struct fc_fcp_pkt *fsp;
1001	struct scsi_cmnd *sc_cmd;
1002	unsigned long flags;
1003
1004	spin_lock_irqsave(&si->scsi_queue_lock, flags);
1005restart:
1006	list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
1007		sc_cmd = fsp->cmd;
1008		if (id != -1 && scmd_id(sc_cmd) != id)
1009			continue;
1010
1011		if (lun != -1 && sc_cmd->device->lun != lun)
1012			continue;
1013
1014		fc_fcp_pkt_hold(fsp);
1015		spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1016
1017		if (!fc_fcp_lock_pkt(fsp)) {
1018			fc_fcp_cleanup_cmd(fsp, error);
1019			fc_io_compl(fsp);
1020			fc_fcp_unlock_pkt(fsp);
1021		}
1022
1023		fc_fcp_pkt_release(fsp);
1024		spin_lock_irqsave(&si->scsi_queue_lock, flags);
1025		/*
1026		 * while we dropped the lock multiple pkts could
1027		 * have been released, so we have to start over.
1028		 */
1029		goto restart;
1030	}
1031	spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1032}
1033
1034/**
1035 * fc_fcp_abort_io() - Abort all FCP-SCSI exchanges on a local port
1036 * @lport: The local port whose exchanges are to be aborted
1037 */
1038static void fc_fcp_abort_io(struct fc_lport *lport)
1039{
1040	fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_HRD_ERROR);
1041}
1042
1043/**
1044 * fc_fcp_pkt_send() - Send a fcp_pkt
1045 * @lport: The local port to send the FCP packet on
1046 * @fsp:   The FCP packet to send
1047 *
1048 * Return:  Zero for success and -1 for failure
1049 * Locks:   Called without locks held
1050 */
1051static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
1052{
1053	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1054	unsigned long flags;
1055	int rc;
1056
1057	fsp->cmd->SCp.ptr = (char *)fsp;
1058	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1059	fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1060
1061	int_to_scsilun(fsp->cmd->device->lun,
1062		       (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1063	memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1064
1065	spin_lock_irqsave(&si->scsi_queue_lock, flags);
1066	list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1067	spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1068	rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv);
1069	if (unlikely(rc)) {
1070		spin_lock_irqsave(&si->scsi_queue_lock, flags);
1071		list_del(&fsp->list);
1072		spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1073	}
1074
1075	return rc;
1076}
1077
1078/**
1079 * fc_fcp_cmd_send() - Send a FCP command
1080 * @lport: The local port to send the command on
1081 * @fsp:   The FCP packet the command is on
1082 * @resp:  The handler for the response
1083 */
1084static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1085			   void (*resp)(struct fc_seq *,
1086					struct fc_frame *fp,
1087					void *arg))
1088{
1089	struct fc_frame *fp;
1090	struct fc_seq *seq;
1091	struct fc_rport *rport;
1092	struct fc_rport_libfc_priv *rpriv;
1093	const size_t len = sizeof(fsp->cdb_cmd);
1094	int rc = 0;
1095
1096	if (fc_fcp_lock_pkt(fsp))
1097		return 0;
1098
1099	fp = fc_fcp_frame_alloc(lport, sizeof(fsp->cdb_cmd));
1100	if (!fp) {
1101		rc = -1;
1102		goto unlock;
1103	}
1104
1105	memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1106	fr_fsp(fp) = fsp;
1107	rport = fsp->rport;
1108	fsp->max_payload = rport->maxframe_size;
1109	rpriv = rport->dd_data;
1110
1111	fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1112		       rpriv->local_port->port_id, FC_TYPE_FCP,
1113		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1114
1115	seq = lport->tt.exch_seq_send(lport, fp, resp, fc_fcp_pkt_destroy,
1116				      fsp, 0);
1117	if (!seq) {
1118		rc = -1;
1119		goto unlock;
1120	}
1121	fsp->last_pkt_time = jiffies;
1122	fsp->seq_ptr = seq;
1123	fc_fcp_pkt_hold(fsp);	/* hold for fc_fcp_pkt_destroy */
1124
1125	setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1126	fc_fcp_timer_set(fsp,
1127			 (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1128			 FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1129unlock:
1130	fc_fcp_unlock_pkt(fsp);
1131	return rc;
1132}
1133
1134/**
1135 * fc_fcp_error() - Handler for FCP layer errors
1136 * @fsp: The FCP packet the error is on
1137 * @fp:	 The frame that has errored
1138 */
1139static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1140{
1141	int error = PTR_ERR(fp);
1142
1143	if (fc_fcp_lock_pkt(fsp))
1144		return;
1145
1146	if (error == -FC_EX_CLOSED) {
1147		fc_fcp_retry_cmd(fsp);
1148		goto unlock;
1149	}
1150
1151	/*
1152	 * clear abort pending, because the lower layer
1153	 * decided to force completion.
1154	 */
1155	fsp->state &= ~FC_SRB_ABORT_PENDING;
1156	fsp->status_code = FC_CMD_PLOGO;
1157	fc_fcp_complete_locked(fsp);
1158unlock:
1159	fc_fcp_unlock_pkt(fsp);
1160}
1161
1162/**
1163 * fc_fcp_pkt_abort() - Abort a fcp_pkt
1164 * @fsp:   The FCP packet to abort on
1165 *
1166 * Called to send an abort and then wait for abort completion
1167 */
1168static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1169{
1170	int rc = FAILED;
1171
1172	if (fc_fcp_send_abort(fsp))
1173		return FAILED;
1174
1175	init_completion(&fsp->tm_done);
1176	fsp->wait_for_comp = 1;
1177
1178	spin_unlock_bh(&fsp->scsi_pkt_lock);
1179	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1180	spin_lock_bh(&fsp->scsi_pkt_lock);
1181	fsp->wait_for_comp = 0;
1182
1183	if (!rc) {
1184		FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1185		rc = FAILED;
1186	} else if (fsp->state & FC_SRB_ABORTED) {
1187		FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1188		rc = SUCCESS;
1189		fc_fcp_complete_locked(fsp);
1190	}
1191
1192	return rc;
1193}
1194
1195/**
1196 * fc_lun_reset_send() - Send LUN reset command
1197 * @data: The FCP packet that identifies the LUN to be reset
1198 */
1199static void fc_lun_reset_send(unsigned long data)
1200{
1201	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1202	struct fc_lport *lport = fsp->lp;
1203	if (lport->tt.fcp_cmd_send(lport, fsp, fc_tm_done)) {
1204		if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1205			return;
1206		if (fc_fcp_lock_pkt(fsp))
1207			return;
1208		setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1209		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1210		fc_fcp_unlock_pkt(fsp);
1211	}
1212}
1213
1214/**
1215 * fc_lun_reset() - Send a LUN RESET command to a device
1216 *		    and wait for the reply
1217 * @lport: The local port to sent the comand on
1218 * @fsp:   The FCP packet that identifies the LUN to be reset
1219 * @id:	   The SCSI command ID
1220 * @lun:   The LUN ID to be reset
1221 */
1222static int fc_lun_reset(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1223			unsigned int id, unsigned int lun)
1224{
1225	int rc;
1226
1227	fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1228	fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1229	int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1230
1231	fsp->wait_for_comp = 1;
1232	init_completion(&fsp->tm_done);
1233
1234	fc_lun_reset_send((unsigned long)fsp);
1235
1236	/*
1237	 * wait for completion of reset
1238	 * after that make sure all commands are terminated
1239	 */
1240	rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1241
1242	spin_lock_bh(&fsp->scsi_pkt_lock);
1243	fsp->state |= FC_SRB_COMPL;
1244	spin_unlock_bh(&fsp->scsi_pkt_lock);
1245
1246	del_timer_sync(&fsp->timer);
1247
1248	spin_lock_bh(&fsp->scsi_pkt_lock);
1249	if (fsp->seq_ptr) {
1250		lport->tt.exch_done(fsp->seq_ptr);
1251		fsp->seq_ptr = NULL;
1252	}
1253	fsp->wait_for_comp = 0;
1254	spin_unlock_bh(&fsp->scsi_pkt_lock);
1255
1256	if (!rc) {
1257		FC_SCSI_DBG(lport, "lun reset failed\n");
1258		return FAILED;
1259	}
1260
1261	/* cdb_status holds the tmf's rsp code */
1262	if (fsp->cdb_status != FCP_TMF_CMPL)
1263		return FAILED;
1264
1265	FC_SCSI_DBG(lport, "lun reset to lun %u completed\n", lun);
1266	fc_fcp_cleanup_each_cmd(lport, id, lun, FC_CMD_ABORTED);
1267	return SUCCESS;
1268}
1269
1270/**
1271 * fc_tm_done() - Task Managment response handler
1272 * @seq: The sequence that the response is on
1273 * @fp:	 The response frame
1274 * @arg: The FCP packet the response is for
1275 */
1276static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1277{
1278	struct fc_fcp_pkt *fsp = arg;
1279	struct fc_frame_header *fh;
1280
1281	if (IS_ERR(fp)) {
1282		/*
1283		 * If there is an error just let it timeout or wait
1284		 * for TMF to be aborted if it timedout.
1285		 *
1286		 * scsi-eh will escalate for when either happens.
1287		 */
1288		return;
1289	}
1290
1291	if (fc_fcp_lock_pkt(fsp))
1292		return;
1293
1294	/*
1295	 * raced with eh timeout handler.
1296	 */
1297	if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1298		spin_unlock_bh(&fsp->scsi_pkt_lock);
1299		return;
1300	}
1301
1302	fh = fc_frame_header_get(fp);
1303	if (fh->fh_type != FC_TYPE_BLS)
1304		fc_fcp_resp(fsp, fp);
1305	fsp->seq_ptr = NULL;
1306	fsp->lp->tt.exch_done(seq);
1307	fc_frame_free(fp);
1308	fc_fcp_unlock_pkt(fsp);
1309}
1310
1311/**
1312 * fc_fcp_cleanup() - Cleanup all FCP exchanges on a local port
1313 * @lport: The local port to be cleaned up
1314 */
1315static void fc_fcp_cleanup(struct fc_lport *lport)
1316{
1317	fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_ERROR);
1318}
1319
1320/**
1321 * fc_fcp_timeout() - Handler for fcp_pkt timeouts
1322 * @data: The FCP packet that has timed out
1323 *
1324 * If REC is supported then just issue it and return. The REC exchange will
1325 * complete or time out and recovery can continue at that point. Otherwise,
1326 * if the response has been received without all the data it has been
1327 * ER_TIMEOUT since the response was received. If the response has not been
1328 * received we see if data was received recently. If it has been then we
1329 * continue waiting, otherwise, we abort the command.
1330 */
1331static void fc_fcp_timeout(unsigned long data)
1332{
1333	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1334	struct fc_rport *rport = fsp->rport;
1335	struct fc_rport_libfc_priv *rpriv = rport->dd_data;
1336
1337	if (fc_fcp_lock_pkt(fsp))
1338		return;
1339
1340	if (fsp->cdb_cmd.fc_tm_flags)
1341		goto unlock;
1342
1343	fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1344
1345	if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
1346		fc_fcp_rec(fsp);
1347	else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1348			       jiffies))
1349		fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1350	else if (fsp->state & FC_SRB_RCV_STATUS)
1351		fc_fcp_complete_locked(fsp);
1352	else
1353		fc_fcp_recovery(fsp);
1354	fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1355unlock:
1356	fc_fcp_unlock_pkt(fsp);
1357}
1358
1359/**
1360 * fc_fcp_rec() - Send a REC ELS request
1361 * @fsp: The FCP packet to send the REC request on
1362 */
1363static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1364{
1365	struct fc_lport *lport;
1366	struct fc_frame *fp;
1367	struct fc_rport *rport;
1368	struct fc_rport_libfc_priv *rpriv;
1369
1370	lport = fsp->lp;
1371	rport = fsp->rport;
1372	rpriv = rport->dd_data;
1373	if (!fsp->seq_ptr || rpriv->rp_state != RPORT_ST_READY) {
1374		fsp->status_code = FC_HRD_ERROR;
1375		fsp->io_status = 0;
1376		fc_fcp_complete_locked(fsp);
1377		return;
1378	}
1379	fp = fc_fcp_frame_alloc(lport, sizeof(struct fc_els_rec));
1380	if (!fp)
1381		goto retry;
1382
1383	fr_seq(fp) = fsp->seq_ptr;
1384	fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1385		       rpriv->local_port->port_id, FC_TYPE_ELS,
1386		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1387	if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC,
1388				 fc_fcp_rec_resp, fsp,
1389				 jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1390		fc_fcp_pkt_hold(fsp);		/* hold while REC outstanding */
1391		return;
1392	}
1393retry:
1394	if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1395		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1396	else
1397		fc_fcp_recovery(fsp);
1398}
1399
1400/**
1401 * fc_fcp_rec_resp() - Handler for REC ELS responses
1402 * @seq: The sequence the response is on
1403 * @fp:	 The response frame
1404 * @arg: The FCP packet the response is on
1405 *
1406 * If the response is a reject then the scsi layer will handle
1407 * the timeout. If the response is a LS_ACC then if the I/O was not completed
1408 * set the timeout and return. If the I/O was completed then complete the
1409 * exchange and tell the SCSI layer.
1410 */
1411static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1412{
1413	struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1414	struct fc_els_rec_acc *recp;
1415	struct fc_els_ls_rjt *rjt;
1416	u32 e_stat;
1417	u8 opcode;
1418	u32 offset;
1419	enum dma_data_direction data_dir;
1420	enum fc_rctl r_ctl;
1421	struct fc_rport_libfc_priv *rpriv;
1422
1423	if (IS_ERR(fp)) {
1424		fc_fcp_rec_error(fsp, fp);
1425		return;
1426	}
1427
1428	if (fc_fcp_lock_pkt(fsp))
1429		goto out;
1430
1431	fsp->recov_retry = 0;
1432	opcode = fc_frame_payload_op(fp);
1433	if (opcode == ELS_LS_RJT) {
1434		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1435		switch (rjt->er_reason) {
1436		default:
1437			FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1438				   "reason %d expl %d\n",
1439				   fsp->rport->port_id, rjt->er_reason,
1440				   rjt->er_explan);
1441			/* fall through */
1442		case ELS_RJT_UNSUP:
1443			FC_FCP_DBG(fsp, "device does not support REC\n");
1444			rpriv = fsp->rport->dd_data;
1445			/*
1446			 * if we do not spport RECs or got some bogus
1447			 * reason then resetup timer so we check for
1448			 * making progress.
1449			 */
1450			rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1451			fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1452			break;
1453		case ELS_RJT_LOGIC:
1454		case ELS_RJT_UNAB:
1455			/*
1456			 * If no data transfer, the command frame got dropped
1457			 * so we just retry.  If data was transferred, we
1458			 * lost the response but the target has no record,
1459			 * so we abort and retry.
1460			 */
1461			if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1462			    fsp->xfer_len == 0) {
1463				fc_fcp_retry_cmd(fsp);
1464				break;
1465			}
1466			fc_fcp_recovery(fsp);
1467			break;
1468		}
1469	} else if (opcode == ELS_LS_ACC) {
1470		if (fsp->state & FC_SRB_ABORTED)
1471			goto unlock_out;
1472
1473		data_dir = fsp->cmd->sc_data_direction;
1474		recp = fc_frame_payload_get(fp, sizeof(*recp));
1475		offset = ntohl(recp->reca_fc4value);
1476		e_stat = ntohl(recp->reca_e_stat);
1477
1478		if (e_stat & ESB_ST_COMPLETE) {
1479
1480			/*
1481			 * The exchange is complete.
1482			 *
1483			 * For output, we must've lost the response.
1484			 * For input, all data must've been sent.
1485			 * We lost may have lost the response
1486			 * (and a confirmation was requested) and maybe
1487			 * some data.
1488			 *
1489			 * If all data received, send SRR
1490			 * asking for response.	 If partial data received,
1491			 * or gaps, SRR requests data at start of gap.
1492			 * Recovery via SRR relies on in-order-delivery.
1493			 */
1494			if (data_dir == DMA_TO_DEVICE) {
1495				r_ctl = FC_RCTL_DD_CMD_STATUS;
1496			} else if (fsp->xfer_contig_end == offset) {
1497				r_ctl = FC_RCTL_DD_CMD_STATUS;
1498			} else {
1499				offset = fsp->xfer_contig_end;
1500				r_ctl = FC_RCTL_DD_SOL_DATA;
1501			}
1502			fc_fcp_srr(fsp, r_ctl, offset);
1503		} else if (e_stat & ESB_ST_SEQ_INIT) {
1504
1505			/*
1506			 * The remote port has the initiative, so just
1507			 * keep waiting for it to complete.
1508			 */
1509			fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1510		} else {
1511
1512			/*
1513			 * The exchange is incomplete, we have seq. initiative.
1514			 * Lost response with requested confirmation,
1515			 * lost confirmation, lost transfer ready or
1516			 * lost write data.
1517			 *
1518			 * For output, if not all data was received, ask
1519			 * for transfer ready to be repeated.
1520			 *
1521			 * If we received or sent all the data, send SRR to
1522			 * request response.
1523			 *
1524			 * If we lost a response, we may have lost some read
1525			 * data as well.
1526			 */
1527			r_ctl = FC_RCTL_DD_SOL_DATA;
1528			if (data_dir == DMA_TO_DEVICE) {
1529				r_ctl = FC_RCTL_DD_CMD_STATUS;
1530				if (offset < fsp->data_len)
1531					r_ctl = FC_RCTL_DD_DATA_DESC;
1532			} else if (offset == fsp->xfer_contig_end) {
1533				r_ctl = FC_RCTL_DD_CMD_STATUS;
1534			} else if (fsp->xfer_contig_end < offset) {
1535				offset = fsp->xfer_contig_end;
1536			}
1537			fc_fcp_srr(fsp, r_ctl, offset);
1538		}
1539	}
1540unlock_out:
1541	fc_fcp_unlock_pkt(fsp);
1542out:
1543	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
1544	fc_frame_free(fp);
1545}
1546
1547/**
1548 * fc_fcp_rec_error() - Handler for REC errors
1549 * @fsp: The FCP packet the error is on
1550 * @fp:	 The REC frame
1551 */
1552static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1553{
1554	int error = PTR_ERR(fp);
1555
1556	if (fc_fcp_lock_pkt(fsp))
1557		goto out;
1558
1559	switch (error) {
1560	case -FC_EX_CLOSED:
1561		fc_fcp_retry_cmd(fsp);
1562		break;
1563
1564	default:
1565		FC_FCP_DBG(fsp, "REC %p fid %6.6x error unexpected error %d\n",
1566			   fsp, fsp->rport->port_id, error);
1567		fsp->status_code = FC_CMD_PLOGO;
1568		/* fall through */
1569
1570	case -FC_EX_TIMEOUT:
1571		/*
1572		 * Assume REC or LS_ACC was lost.
1573		 * The exchange manager will have aborted REC, so retry.
1574		 */
1575		FC_FCP_DBG(fsp, "REC fid %6.6x error error %d retry %d/%d\n",
1576			   fsp->rport->port_id, error, fsp->recov_retry,
1577			   FC_MAX_RECOV_RETRY);
1578		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1579			fc_fcp_rec(fsp);
1580		else
1581			fc_fcp_recovery(fsp);
1582		break;
1583	}
1584	fc_fcp_unlock_pkt(fsp);
1585out:
1586	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding REC */
1587}
1588
1589/**
1590 * fc_fcp_recovery() - Handler for fcp_pkt recovery
1591 * @fsp: The FCP pkt that needs to be aborted
1592 */
1593static void fc_fcp_recovery(struct fc_fcp_pkt *fsp)
1594{
1595	fsp->status_code = FC_CMD_RECOVERY;
1596	fsp->cdb_status = 0;
1597	fsp->io_status = 0;
1598	/*
1599	 * if this fails then we let the scsi command timer fire and
1600	 * scsi-ml escalate.
1601	 */
1602	fc_fcp_send_abort(fsp);
1603}
1604
1605/**
1606 * fc_fcp_srr() - Send a SRR request (Sequence Retransmission Request)
1607 * @fsp:   The FCP packet the SRR is to be sent on
1608 * @r_ctl: The R_CTL field for the SRR request
1609 * This is called after receiving status but insufficient data, or
1610 * when expecting status but the request has timed out.
1611 */
1612static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1613{
1614	struct fc_lport *lport = fsp->lp;
1615	struct fc_rport *rport;
1616	struct fc_rport_libfc_priv *rpriv;
1617	struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1618	struct fc_seq *seq;
1619	struct fcp_srr *srr;
1620	struct fc_frame *fp;
1621	u8 cdb_op;
1622
1623	rport = fsp->rport;
1624	rpriv = rport->dd_data;
1625	cdb_op = fsp->cdb_cmd.fc_cdb[0];
1626
1627	if (!(rpriv->flags & FC_RP_FLAGS_RETRY) ||
1628	    rpriv->rp_state != RPORT_ST_READY)
1629		goto retry;			/* shouldn't happen */
1630	fp = fc_fcp_frame_alloc(lport, sizeof(*srr));
1631	if (!fp)
1632		goto retry;
1633
1634	srr = fc_frame_payload_get(fp, sizeof(*srr));
1635	memset(srr, 0, sizeof(*srr));
1636	srr->srr_op = ELS_SRR;
1637	srr->srr_ox_id = htons(ep->oxid);
1638	srr->srr_rx_id = htons(ep->rxid);
1639	srr->srr_r_ctl = r_ctl;
1640	srr->srr_rel_off = htonl(offset);
1641
1642	fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1643		       rpriv->local_port->port_id, FC_TYPE_FCP,
1644		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1645
1646	seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, NULL,
1647				      fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1648	if (!seq)
1649		goto retry;
1650
1651	fsp->recov_seq = seq;
1652	fsp->xfer_len = offset;
1653	fsp->xfer_contig_end = offset;
1654	fsp->state &= ~FC_SRB_RCV_STATUS;
1655	fc_fcp_pkt_hold(fsp);		/* hold for outstanding SRR */
1656	return;
1657retry:
1658	fc_fcp_retry_cmd(fsp);
1659}
1660
1661/**
1662 * fc_fcp_srr_resp() - Handler for SRR response
1663 * @seq: The sequence the SRR is on
1664 * @fp:	 The SRR frame
1665 * @arg: The FCP packet the SRR is on
1666 */
1667static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1668{
1669	struct fc_fcp_pkt *fsp = arg;
1670	struct fc_frame_header *fh;
1671
1672	if (IS_ERR(fp)) {
1673		fc_fcp_srr_error(fsp, fp);
1674		return;
1675	}
1676
1677	if (fc_fcp_lock_pkt(fsp))
1678		goto out;
1679
1680	fh = fc_frame_header_get(fp);
1681	/*
1682	 * BUG? fc_fcp_srr_error calls exch_done which would release
1683	 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1684	 * then fc_exch_timeout would be sending an abort. The exch_done
1685	 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1686	 * an abort response though.
1687	 */
1688	if (fh->fh_type == FC_TYPE_BLS) {
1689		fc_fcp_unlock_pkt(fsp);
1690		return;
1691	}
1692
1693	fsp->recov_seq = NULL;
1694	switch (fc_frame_payload_op(fp)) {
1695	case ELS_LS_ACC:
1696		fsp->recov_retry = 0;
1697		fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1698		break;
1699	case ELS_LS_RJT:
1700	default:
1701		fc_fcp_recovery(fsp);
1702		break;
1703	}
1704	fc_fcp_unlock_pkt(fsp);
1705	fsp->lp->tt.exch_done(seq);
1706out:
1707	fc_frame_free(fp);
1708	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
1709}
1710
1711/**
1712 * fc_fcp_srr_error() - Handler for SRR errors
1713 * @fsp: The FCP packet that the SRR error is on
1714 * @fp:	 The SRR frame
1715 */
1716static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1717{
1718	if (fc_fcp_lock_pkt(fsp))
1719		goto out;
1720	fsp->lp->tt.exch_done(fsp->recov_seq);
1721	fsp->recov_seq = NULL;
1722	switch (PTR_ERR(fp)) {
1723	case -FC_EX_TIMEOUT:
1724		if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1725			fc_fcp_rec(fsp);
1726		else
1727			fc_fcp_recovery(fsp);
1728		break;
1729	case -FC_EX_CLOSED:			/* e.g., link failure */
1730		/* fall through */
1731	default:
1732		fc_fcp_retry_cmd(fsp);
1733		break;
1734	}
1735	fc_fcp_unlock_pkt(fsp);
1736out:
1737	fc_fcp_pkt_release(fsp);	/* drop hold for outstanding SRR */
1738}
1739
1740/**
1741 * fc_fcp_lport_queue_ready() - Determine if the lport and it's queue is ready
1742 * @lport: The local port to be checked
1743 */
1744static inline int fc_fcp_lport_queue_ready(struct fc_lport *lport)
1745{
1746	/* lock ? */
1747	return (lport->state == LPORT_ST_READY) &&
1748		lport->link_up && !lport->qfull;
1749}
1750
1751/**
1752 * fc_queuecommand() - The queuecommand function of the SCSI template
1753 * @cmd:   The scsi_cmnd to be executed
1754 * @done:  The callback function to be called when the scsi_cmnd is complete
1755 *
1756 * This is the i/o strategy routine, called by the SCSI layer. This routine
1757 * is called with the host_lock held.
1758 */
1759int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1760{
1761	struct fc_lport *lport;
1762	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1763	struct fc_fcp_pkt *fsp;
1764	struct fc_rport_libfc_priv *rpriv;
1765	int rval;
1766	int rc = 0;
1767	struct fcoe_dev_stats *stats;
1768
1769	lport = shost_priv(sc_cmd->device->host);
1770	spin_unlock_irq(lport->host->host_lock);
1771
1772	rval = fc_remote_port_chkready(rport);
1773	if (rval) {
1774		sc_cmd->result = rval;
1775		done(sc_cmd);
1776		goto out;
1777	}
1778
1779	if (!*(struct fc_remote_port **)rport->dd_data) {
1780		/*
1781		 * rport is transitioning from blocked/deleted to
1782		 * online
1783		 */
1784		sc_cmd->result = DID_IMM_RETRY << 16;
1785		done(sc_cmd);
1786		goto out;
1787	}
1788
1789	rpriv = rport->dd_data;
1790
1791	if (!fc_fcp_lport_queue_ready(lport)) {
1792		if (lport->qfull)
1793			fc_fcp_can_queue_ramp_down(lport);
1794		rc = SCSI_MLQUEUE_HOST_BUSY;
1795		goto out;
1796	}
1797
1798	fsp = fc_fcp_pkt_alloc(lport, GFP_ATOMIC);
1799	if (fsp == NULL) {
1800		rc = SCSI_MLQUEUE_HOST_BUSY;
1801		goto out;
1802	}
1803
1804	/*
1805	 * build the libfc request pkt
1806	 */
1807	fsp->cmd = sc_cmd;	/* save the cmd */
1808	fsp->lp = lport;	/* save the softc ptr */
1809	fsp->rport = rport;	/* set the remote port ptr */
1810	fsp->xfer_ddp = FC_XID_UNKNOWN;
1811	sc_cmd->scsi_done = done;
1812
1813	/*
1814	 * set up the transfer length
1815	 */
1816	fsp->data_len = scsi_bufflen(sc_cmd);
1817	fsp->xfer_len = 0;
1818
1819	/*
1820	 * setup the data direction
1821	 */
1822	stats = per_cpu_ptr(lport->dev_stats, get_cpu());
1823	if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1824		fsp->req_flags = FC_SRB_READ;
1825		stats->InputRequests++;
1826		stats->InputMegabytes = fsp->data_len;
1827	} else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1828		fsp->req_flags = FC_SRB_WRITE;
1829		stats->OutputRequests++;
1830		stats->OutputMegabytes = fsp->data_len;
1831	} else {
1832		fsp->req_flags = 0;
1833		stats->ControlRequests++;
1834	}
1835	put_cpu();
1836
1837	fsp->tgt_flags = rpriv->flags;
1838
1839	init_timer(&fsp->timer);
1840	fsp->timer.data = (unsigned long)fsp;
1841
1842	/*
1843	 * send it to the lower layer
1844	 * if we get -1 return then put the request in the pending
1845	 * queue.
1846	 */
1847	rval = fc_fcp_pkt_send(lport, fsp);
1848	if (rval != 0) {
1849		fsp->state = FC_SRB_FREE;
1850		fc_fcp_pkt_release(fsp);
1851		rc = SCSI_MLQUEUE_HOST_BUSY;
1852	}
1853out:
1854	spin_lock_irq(lport->host->host_lock);
1855	return rc;
1856}
1857EXPORT_SYMBOL(fc_queuecommand);
1858
1859/**
1860 * fc_io_compl() - Handle responses for completed commands
1861 * @fsp: The FCP packet that is complete
1862 *
1863 * Translates fcp_pkt errors to a Linux SCSI errors.
1864 * The fcp packet lock must be held when calling.
1865 */
1866static void fc_io_compl(struct fc_fcp_pkt *fsp)
1867{
1868	struct fc_fcp_internal *si;
1869	struct scsi_cmnd *sc_cmd;
1870	struct fc_lport *lport;
1871	unsigned long flags;
1872
1873	/* release outstanding ddp context */
1874	fc_fcp_ddp_done(fsp);
1875
1876	fsp->state |= FC_SRB_COMPL;
1877	if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1878		spin_unlock_bh(&fsp->scsi_pkt_lock);
1879		del_timer_sync(&fsp->timer);
1880		spin_lock_bh(&fsp->scsi_pkt_lock);
1881	}
1882
1883	lport = fsp->lp;
1884	si = fc_get_scsi_internal(lport);
1885	if (!fsp->cmd)
1886		return;
1887
1888	/*
1889	 * if can_queue ramp down is done then try can_queue ramp up
1890	 * since commands are completing now.
1891	 */
1892	if (si->last_can_queue_ramp_down_time)
1893		fc_fcp_can_queue_ramp_up(lport);
1894
1895	sc_cmd = fsp->cmd;
1896	fsp->cmd = NULL;
1897
1898	if (!sc_cmd->SCp.ptr)
1899		return;
1900
1901	CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1902	switch (fsp->status_code) {
1903	case FC_COMPLETE:
1904		if (fsp->cdb_status == 0) {
1905			/*
1906			 * good I/O status
1907			 */
1908			sc_cmd->result = DID_OK << 16;
1909			if (fsp->scsi_resid)
1910				CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1911		} else {
1912			/*
1913			 * transport level I/O was ok but scsi
1914			 * has non zero status
1915			 */
1916			sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1917		}
1918		break;
1919	case FC_ERROR:
1920		FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1921			   "due to FC_ERROR\n");
1922		sc_cmd->result = DID_ERROR << 16;
1923		break;
1924	case FC_DATA_UNDRUN:
1925		if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1926			/*
1927			 * scsi status is good but transport level
1928			 * underrun.
1929			 */
1930			if (fsp->state & FC_SRB_RCV_STATUS) {
1931				sc_cmd->result = DID_OK << 16;
1932			} else {
1933				FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml"
1934					   " due to FC_DATA_UNDRUN (trans)\n");
1935				sc_cmd->result = DID_ERROR << 16;
1936			}
1937		} else {
1938			/*
1939			 * scsi got underrun, this is an error
1940			 */
1941			FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1942				   "due to FC_DATA_UNDRUN (scsi)\n");
1943			CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1944			sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1945		}
1946		break;
1947	case FC_DATA_OVRRUN:
1948		/*
1949		 * overrun is an error
1950		 */
1951		FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1952			   "due to FC_DATA_OVRRUN\n");
1953		sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1954		break;
1955	case FC_CMD_ABORTED:
1956		FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1957			   "due to FC_CMD_ABORTED\n");
1958		sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1959		break;
1960	case FC_CMD_RECOVERY:
1961		sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1962		break;
1963	case FC_CMD_RESET:
1964		sc_cmd->result = (DID_RESET << 16);
1965		break;
1966	case FC_HRD_ERROR:
1967		sc_cmd->result = (DID_NO_CONNECT << 16);
1968		break;
1969	default:
1970		FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1971			   "due to unknown error\n");
1972		sc_cmd->result = (DID_ERROR << 16);
1973		break;
1974	}
1975
1976	spin_lock_irqsave(&si->scsi_queue_lock, flags);
1977	list_del(&fsp->list);
1978	spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1979	sc_cmd->SCp.ptr = NULL;
1980	sc_cmd->scsi_done(sc_cmd);
1981
1982	/* release ref from initial allocation in queue command */
1983	fc_fcp_pkt_release(fsp);
1984}
1985
1986/**
1987 * fc_eh_abort() - Abort a command
1988 * @sc_cmd: The SCSI command to abort
1989 *
1990 * From SCSI host template.
1991 * Send an ABTS to the target device and wait for the response.
1992 */
1993int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1994{
1995	struct fc_fcp_pkt *fsp;
1996	struct fc_lport *lport;
1997	int rc = FAILED;
1998	unsigned long flags;
1999
2000	lport = shost_priv(sc_cmd->device->host);
2001	if (lport->state != LPORT_ST_READY)
2002		return rc;
2003	else if (!lport->link_up)
2004		return rc;
2005
2006	spin_lock_irqsave(lport->host->host_lock, flags);
2007	fsp = CMD_SP(sc_cmd);
2008	if (!fsp) {
2009		/* command completed while scsi eh was setting up */
2010		spin_unlock_irqrestore(lport->host->host_lock, flags);
2011		return SUCCESS;
2012	}
2013	/* grab a ref so the fsp and sc_cmd cannot be relased from under us */
2014	fc_fcp_pkt_hold(fsp);
2015	spin_unlock_irqrestore(lport->host->host_lock, flags);
2016
2017	if (fc_fcp_lock_pkt(fsp)) {
2018		/* completed while we were waiting for timer to be deleted */
2019		rc = SUCCESS;
2020		goto release_pkt;
2021	}
2022
2023	rc = fc_fcp_pkt_abort(fsp);
2024	fc_fcp_unlock_pkt(fsp);
2025
2026release_pkt:
2027	fc_fcp_pkt_release(fsp);
2028	return rc;
2029}
2030EXPORT_SYMBOL(fc_eh_abort);
2031
2032/**
2033 * fc_eh_device_reset() - Reset a single LUN
2034 * @sc_cmd: The SCSI command which identifies the device whose
2035 *	    LUN is to be reset
2036 *
2037 * Set from SCSI host template.
2038 */
2039int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
2040{
2041	struct fc_lport *lport;
2042	struct fc_fcp_pkt *fsp;
2043	struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
2044	int rc = FAILED;
2045	int rval;
2046
2047	rval = fc_remote_port_chkready(rport);
2048	if (rval)
2049		goto out;
2050
2051	lport = shost_priv(sc_cmd->device->host);
2052
2053	if (lport->state != LPORT_ST_READY)
2054		return rc;
2055
2056	FC_SCSI_DBG(lport, "Resetting rport (%6.6x)\n", rport->port_id);
2057
2058	fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO);
2059	if (fsp == NULL) {
2060		printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
2061		goto out;
2062	}
2063
2064	/*
2065	 * Build the libfc request pkt. Do not set the scsi cmnd, because
2066	 * the sc passed in is not setup for execution like when sent
2067	 * through the queuecommand callout.
2068	 */
2069	fsp->lp = lport;	/* save the softc ptr */
2070	fsp->rport = rport;	/* set the remote port ptr */
2071
2072	/*
2073	 * flush outstanding commands
2074	 */
2075	rc = fc_lun_reset(lport, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2076	fsp->state = FC_SRB_FREE;
2077	fc_fcp_pkt_release(fsp);
2078
2079out:
2080	return rc;
2081}
2082EXPORT_SYMBOL(fc_eh_device_reset);
2083
2084/**
2085 * fc_eh_host_reset() - Reset a Scsi_Host.
2086 * @sc_cmd: The SCSI command that identifies the SCSI host to be reset
2087 */
2088int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2089{
2090	struct Scsi_Host *shost = sc_cmd->device->host;
2091	struct fc_lport *lport = shost_priv(shost);
2092	unsigned long wait_tmo;
2093
2094	FC_SCSI_DBG(lport, "Resetting host\n");
2095
2096	lport->tt.lport_reset(lport);
2097	wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2098	while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies,
2099							       wait_tmo))
2100		msleep(1000);
2101
2102	if (fc_fcp_lport_queue_ready(lport)) {
2103		shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2104			     "on port (%6.6x)\n", lport->port_id);
2105		return SUCCESS;
2106	} else {
2107		shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2108			     "port (%6.6x) is not ready.\n",
2109			     lport->port_id);
2110		return FAILED;
2111	}
2112}
2113EXPORT_SYMBOL(fc_eh_host_reset);
2114
2115/**
2116 * fc_slave_alloc() - Configure the queue depth of a Scsi_Host
2117 * @sdev: The SCSI device that identifies the SCSI host
2118 *
2119 * Configures queue depth based on host's cmd_per_len. If not set
2120 * then we use the libfc default.
2121 */
2122int fc_slave_alloc(struct scsi_device *sdev)
2123{
2124	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2125
2126	if (!rport || fc_remote_port_chkready(rport))
2127		return -ENXIO;
2128
2129	if (sdev->tagged_supported)
2130		scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2131	else
2132		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
2133					FC_FCP_DFLT_QUEUE_DEPTH);
2134
2135	return 0;
2136}
2137EXPORT_SYMBOL(fc_slave_alloc);
2138
2139/**
2140 * fc_change_queue_depth() - Change a device's queue depth
2141 * @sdev:   The SCSI device whose queue depth is to change
2142 * @qdepth: The new queue depth
2143 * @reason: The resason for the change
2144 */
2145int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
2146{
2147	switch (reason) {
2148	case SCSI_QDEPTH_DEFAULT:
2149		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2150		break;
2151	case SCSI_QDEPTH_QFULL:
2152		scsi_track_queue_full(sdev, qdepth);
2153		break;
2154	case SCSI_QDEPTH_RAMP_UP:
2155		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2156		break;
2157	default:
2158		return -EOPNOTSUPP;
2159	}
2160	return sdev->queue_depth;
2161}
2162EXPORT_SYMBOL(fc_change_queue_depth);
2163
2164/**
2165 * fc_change_queue_type() - Change a device's queue type
2166 * @sdev:     The SCSI device whose queue depth is to change
2167 * @tag_type: Identifier for queue type
2168 */
2169int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2170{
2171	if (sdev->tagged_supported) {
2172		scsi_set_tag_type(sdev, tag_type);
2173		if (tag_type)
2174			scsi_activate_tcq(sdev, sdev->queue_depth);
2175		else
2176			scsi_deactivate_tcq(sdev, sdev->queue_depth);
2177	} else
2178		tag_type = 0;
2179
2180	return tag_type;
2181}
2182EXPORT_SYMBOL(fc_change_queue_type);
2183
2184/**
2185 * fc_fcp_destory() - Tear down the FCP layer for a given local port
2186 * @lport: The local port that no longer needs the FCP layer
2187 */
2188void fc_fcp_destroy(struct fc_lport *lport)
2189{
2190	struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
2191
2192	if (!list_empty(&si->scsi_pkt_queue))
2193		printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2194		       "port (%6.6x)\n", lport->port_id);
2195
2196	mempool_destroy(si->scsi_pkt_pool);
2197	kfree(si);
2198	lport->scsi_priv = NULL;
2199}
2200EXPORT_SYMBOL(fc_fcp_destroy);
2201
2202int fc_setup_fcp()
2203{
2204	int rc = 0;
2205
2206	scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2207					    sizeof(struct fc_fcp_pkt),
2208					    0, SLAB_HWCACHE_ALIGN, NULL);
2209	if (!scsi_pkt_cachep) {
2210		printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2211		       "module load failed!");
2212		rc = -ENOMEM;
2213	}
2214
2215	return rc;
2216}
2217
2218void fc_destroy_fcp()
2219{
2220	if (scsi_pkt_cachep)
2221		kmem_cache_destroy(scsi_pkt_cachep);
2222}
2223
2224/**
2225 * fc_fcp_init() - Initialize the FCP layer for a local port
2226 * @lport: The local port to initialize the exchange layer for
2227 */
2228int fc_fcp_init(struct fc_lport *lport)
2229{
2230	int rc;
2231	struct fc_fcp_internal *si;
2232
2233	if (!lport->tt.fcp_cmd_send)
2234		lport->tt.fcp_cmd_send = fc_fcp_cmd_send;
2235
2236	if (!lport->tt.fcp_cleanup)
2237		lport->tt.fcp_cleanup = fc_fcp_cleanup;
2238
2239	if (!lport->tt.fcp_abort_io)
2240		lport->tt.fcp_abort_io = fc_fcp_abort_io;
2241
2242	si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2243	if (!si)
2244		return -ENOMEM;
2245	lport->scsi_priv = si;
2246	si->max_can_queue = lport->host->can_queue;
2247	INIT_LIST_HEAD(&si->scsi_pkt_queue);
2248	spin_lock_init(&si->scsi_queue_lock);
2249
2250	si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2251	if (!si->scsi_pkt_pool) {
2252		rc = -ENOMEM;
2253		goto free_internal;
2254	}
2255	return 0;
2256
2257free_internal:
2258	kfree(si);
2259	return rc;
2260}
2261EXPORT_SYMBOL(fc_fcp_init);
2262