libfc: Add runtime debugging with debug_logging module parameter
[linux-2.6.git] / drivers / scsi / libfc / fc_fcp.c
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
31 #include <scsi/scsi_tcq.h>
32 #include <scsi/scsi.h>
33 #include <scsi/scsi_host.h>
34 #include <scsi/scsi_device.h>
35 #include <scsi/scsi_cmnd.h>
36
37 #include <scsi/fc/fc_fc2.h>
38
39 #include <scsi/libfc.h>
40 #include <scsi/fc_encode.h>
41
42 MODULE_AUTHOR("Open-FCoE.org");
43 MODULE_DESCRIPTION("libfc");
44 MODULE_LICENSE("GPL v2");
45
46 unsigned int fc_debug_logging;
47 module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR);
48 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
49
50 static struct kmem_cache *scsi_pkt_cachep;
51
52 /* SRB state definitions */
53 #define FC_SRB_FREE             0               /* cmd is free */
54 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
55 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
56 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
57 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
58 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
59 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
60 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
61 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
62
63 #define FC_SRB_READ             (1 << 1)
64 #define FC_SRB_WRITE            (1 << 0)
65
66 /*
67  * The SCp.ptr should be tested and set under the host lock. NULL indicates
68  * that the command has been retruned to the scsi layer.
69  */
70 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
71 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
72 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
73 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
74 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
75
76 struct fc_fcp_internal {
77         mempool_t       *scsi_pkt_pool;
78         struct list_head scsi_pkt_queue;
79         u8              throttled;
80 };
81
82 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
83
84 /*
85  * function prototypes
86  * FC scsi I/O related functions
87  */
88 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
89 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
90 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
91 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
92 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
93 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
94 static void fc_timeout_error(struct fc_fcp_pkt *);
95 static void fc_fcp_timeout(unsigned long data);
96 static void fc_fcp_rec(struct fc_fcp_pkt *);
97 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
98 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
99 static void fc_io_compl(struct fc_fcp_pkt *);
100
101 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
102 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
103 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
104
105 /*
106  * command status codes
107  */
108 #define FC_COMPLETE             0
109 #define FC_CMD_ABORTED          1
110 #define FC_CMD_RESET            2
111 #define FC_CMD_PLOGO            3
112 #define FC_SNS_RCV              4
113 #define FC_TRANS_ERR            5
114 #define FC_DATA_OVRRUN          6
115 #define FC_DATA_UNDRUN          7
116 #define FC_ERROR                8
117 #define FC_HRD_ERROR            9
118 #define FC_CMD_TIME_OUT         10
119
120 /*
121  * Error recovery timeout values.
122  */
123 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
124 #define FC_SCSI_TM_TOV          (10 * HZ)
125 #define FC_SCSI_REC_TOV         (2 * HZ)
126 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
127
128 #define FC_MAX_ERROR_CNT        5
129 #define FC_MAX_RECOV_RETRY      3
130
131 #define FC_FCP_DFLT_QUEUE_DEPTH 32
132
133 /**
134  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
135  * @lp:         fc lport struct
136  * @gfp:        gfp flags for allocation
137  *
138  * This is used by upper layer scsi driver.
139  * Return Value : scsi_pkt structure or null on allocation failure.
140  * Context      : call from process context. no locking required.
141  */
142 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
143 {
144         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
145         struct fc_fcp_pkt *fsp;
146
147         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
148         if (fsp) {
149                 memset(fsp, 0, sizeof(*fsp));
150                 fsp->lp = lp;
151                 atomic_set(&fsp->ref_cnt, 1);
152                 init_timer(&fsp->timer);
153                 INIT_LIST_HEAD(&fsp->list);
154                 spin_lock_init(&fsp->scsi_pkt_lock);
155         }
156         return fsp;
157 }
158
159 /**
160  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
161  * @fsp:        fcp packet struct
162  *
163  * This is used by upper layer scsi driver.
164  * Context      : call from process  and interrupt context.
165  *                no locking required
166  */
167 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
168 {
169         if (atomic_dec_and_test(&fsp->ref_cnt)) {
170                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
171
172                 mempool_free(fsp, si->scsi_pkt_pool);
173         }
174 }
175
176 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
177 {
178         atomic_inc(&fsp->ref_cnt);
179 }
180
181 /**
182  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
183  * @seq:                exchange sequence
184  * @fsp:        fcp packet struct
185  *
186  * Release hold on scsi_pkt packet set to keep scsi_pkt
187  * till EM layer exch resource is not freed.
188  * Context      : called from from EM layer.
189  *                no locking required
190  */
191 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
192 {
193         fc_fcp_pkt_release(fsp);
194 }
195
196 /**
197  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
198  * @fsp:        fcp packet
199  *
200  * We should only return error if we return a command to scsi-ml before
201  * getting a response. This can happen in cases where we send a abort, but
202  * do not wait for the response and the abort and command can be passing
203  * each other on the wire/network-layer.
204  *
205  * Note: this function locks the packet and gets a reference to allow
206  * callers to call the completion function while the lock is held and
207  * not have to worry about the packets refcount.
208  *
209  * TODO: Maybe we should just have callers grab/release the lock and
210  * have a function that they call to verify the fsp and grab a ref if
211  * needed.
212  */
213 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
214 {
215         spin_lock_bh(&fsp->scsi_pkt_lock);
216         if (fsp->state & FC_SRB_COMPL) {
217                 spin_unlock_bh(&fsp->scsi_pkt_lock);
218                 return -EPERM;
219         }
220
221         fc_fcp_pkt_hold(fsp);
222         return 0;
223 }
224
225 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
226 {
227         spin_unlock_bh(&fsp->scsi_pkt_lock);
228         fc_fcp_pkt_release(fsp);
229 }
230
231 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
232 {
233         if (!(fsp->state & FC_SRB_COMPL))
234                 mod_timer(&fsp->timer, jiffies + delay);
235 }
236
237 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
238 {
239         if (!fsp->seq_ptr)
240                 return -EINVAL;
241
242         fsp->state |= FC_SRB_ABORT_PENDING;
243         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
244 }
245
246 /*
247  * Retry command.
248  * An abort isn't needed.
249  */
250 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
251 {
252         if (fsp->seq_ptr) {
253                 fsp->lp->tt.exch_done(fsp->seq_ptr);
254                 fsp->seq_ptr = NULL;
255         }
256
257         fsp->state &= ~FC_SRB_ABORT_PENDING;
258         fsp->io_status = 0;
259         fsp->status_code = FC_ERROR;
260         fc_fcp_complete_locked(fsp);
261 }
262
263 /*
264  * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
265  * transfer for a read I/O indicated by the fc_fcp_pkt.
266  * @fsp: ptr to the fc_fcp_pkt
267  *
268  * This is called in exch_seq_send() when we have a newly allocated
269  * exchange with a valid exchange id to setup ddp.
270  *
271  * returns: none
272  */
273 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
274 {
275         struct fc_lport *lp;
276
277         if (!fsp)
278                 return;
279
280         lp = fsp->lp;
281         if ((fsp->req_flags & FC_SRB_READ) &&
282             (lp->lro_enabled) && (lp->tt.ddp_setup)) {
283                 if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
284                                      scsi_sg_count(fsp->cmd)))
285                         fsp->xfer_ddp = xid;
286         }
287 }
288 EXPORT_SYMBOL(fc_fcp_ddp_setup);
289
290 /*
291  * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
292  * DDP related resources for this I/O if it is initialized
293  * as a ddp transfer
294  * @fsp: ptr to the fc_fcp_pkt
295  *
296  * returns: none
297  */
298 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
299 {
300         struct fc_lport *lp;
301
302         if (!fsp)
303                 return;
304
305         lp = fsp->lp;
306         if (fsp->xfer_ddp && lp->tt.ddp_done) {
307                 fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
308                 fsp->xfer_ddp = 0;
309         }
310 }
311
312
313 /*
314  * Receive SCSI data from target.
315  * Called after receiving solicited data.
316  */
317 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
318 {
319         struct scsi_cmnd *sc = fsp->cmd;
320         struct fc_lport *lp = fsp->lp;
321         struct fcoe_dev_stats *stats;
322         struct fc_frame_header *fh;
323         size_t start_offset;
324         size_t offset;
325         u32 crc;
326         u32 copy_len = 0;
327         size_t len;
328         void *buf;
329         struct scatterlist *sg;
330         size_t remaining;
331
332         fh = fc_frame_header_get(fp);
333         offset = ntohl(fh->fh_parm_offset);
334         start_offset = offset;
335         len = fr_len(fp) - sizeof(*fh);
336         buf = fc_frame_payload_get(fp, 0);
337
338         /* if this I/O is ddped, update xfer len */
339         fc_fcp_ddp_done(fsp);
340
341         if (offset + len > fsp->data_len) {
342                 /* this should never happen */
343                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
344                     fc_frame_crc_check(fp))
345                         goto crc_err;
346                 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
347                            "data_len %x\n", len, offset, fsp->data_len);
348                 fc_fcp_retry_cmd(fsp);
349                 return;
350         }
351         if (offset != fsp->xfer_len)
352                 fsp->state |= FC_SRB_DISCONTIG;
353
354         crc = 0;
355         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
356                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
357
358         sg = scsi_sglist(sc);
359         remaining = len;
360
361         while (remaining > 0 && sg) {
362                 size_t off;
363                 void *page_addr;
364                 size_t sg_bytes;
365
366                 if (offset >= sg->length) {
367                         offset -= sg->length;
368                         sg = sg_next(sg);
369                         continue;
370                 }
371                 sg_bytes = min(remaining, sg->length - offset);
372
373                 /*
374                  * The scatterlist item may be bigger than PAGE_SIZE,
375                  * but we are limited to mapping PAGE_SIZE at a time.
376                  */
377                 off = offset + sg->offset;
378                 sg_bytes = min(sg_bytes, (size_t)
379                                (PAGE_SIZE - (off & ~PAGE_MASK)));
380                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
381                                         KM_SOFTIRQ0);
382                 if (!page_addr)
383                         break;          /* XXX panic? */
384
385                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
386                         crc = crc32(crc, buf, sg_bytes);
387                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
388                        sg_bytes);
389
390                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
391                 buf += sg_bytes;
392                 offset += sg_bytes;
393                 remaining -= sg_bytes;
394                 copy_len += sg_bytes;
395         }
396
397         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
398                 buf = fc_frame_payload_get(fp, 0);
399                 if (len % 4) {
400                         crc = crc32(crc, buf + len, 4 - (len % 4));
401                         len += 4 - (len % 4);
402                 }
403
404                 if (~crc != le32_to_cpu(fr_crc(fp))) {
405 crc_err:
406                         stats = fc_lport_get_stats(lp);
407                         stats->ErrorFrames++;
408                         /* FIXME - per cpu count, not total count! */
409                         if (stats->InvalidCRCCount++ < 5)
410                                 printk(KERN_WARNING "libfc: CRC error on data "
411                                        "frame for port (%6x)\n",
412                                        fc_host_port_id(lp->host));
413                         /*
414                          * Assume the frame is total garbage.
415                          * We may have copied it over the good part
416                          * of the buffer.
417                          * If so, we need to retry the entire operation.
418                          * Otherwise, ignore it.
419                          */
420                         if (fsp->state & FC_SRB_DISCONTIG)
421                                 fc_fcp_retry_cmd(fsp);
422                         return;
423                 }
424         }
425
426         if (fsp->xfer_contig_end == start_offset)
427                 fsp->xfer_contig_end += copy_len;
428         fsp->xfer_len += copy_len;
429
430         /*
431          * In the very rare event that this data arrived after the response
432          * and completes the transfer, call the completion handler.
433          */
434         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
435             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
436                 fc_fcp_complete_locked(fsp);
437 }
438
439 /**
440  * fc_fcp_send_data() -  Send SCSI data to target.
441  * @fsp: ptr to fc_fcp_pkt
442  * @sp: ptr to this sequence
443  * @offset: starting offset for this data request
444  * @seq_blen: the burst length for this data request
445  *
446  * Called after receiving a Transfer Ready data descriptor.
447  * if LLD is capable of seq offload then send down seq_blen
448  * size of data in single frame, otherwise send multiple FC
449  * frames of max FC frame payload supported by target port.
450  *
451  * Returns : 0 for success.
452  */
453 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
454                             size_t offset, size_t seq_blen)
455 {
456         struct fc_exch *ep;
457         struct scsi_cmnd *sc;
458         struct scatterlist *sg;
459         struct fc_frame *fp = NULL;
460         struct fc_lport *lp = fsp->lp;
461         size_t remaining;
462         size_t t_blen;
463         size_t tlen;
464         size_t sg_bytes;
465         size_t frame_offset, fh_parm_offset;
466         int error;
467         void *data = NULL;
468         void *page_addr;
469         int using_sg = lp->sg_supp;
470         u32 f_ctl;
471
472         WARN_ON(seq_blen <= 0);
473         if (unlikely(offset + seq_blen > fsp->data_len)) {
474                 /* this should never happen */
475                 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
476                            "offset %zx\n", seq_blen, offset);
477                 fc_fcp_send_abort(fsp);
478                 return 0;
479         } else if (offset != fsp->xfer_len) {
480                 /* Out of Order Data Request - no problem, but unexpected. */
481                 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
482                            "seq_blen %zx offset %zx\n", seq_blen, offset);
483         }
484
485         /*
486          * if LLD is capable of seq_offload then set transport
487          * burst length (t_blen) to seq_blen, otherwise set t_blen
488          * to max FC frame payload previously set in fsp->max_payload.
489          */
490         t_blen = fsp->max_payload;
491         if (lp->seq_offload) {
492                 t_blen = min(seq_blen, (size_t)lp->lso_max);
493                 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
494                            fsp, seq_blen, lp->lso_max, t_blen);
495         }
496
497         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
498         if (t_blen > 512)
499                 t_blen &= ~(512 - 1);   /* round down to block size */
500         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
501         sc = fsp->cmd;
502
503         remaining = seq_blen;
504         fh_parm_offset = frame_offset = offset;
505         tlen = 0;
506         seq = lp->tt.seq_start_next(seq);
507         f_ctl = FC_FC_REL_OFF;
508         WARN_ON(!seq);
509
510         /*
511          * If a get_page()/put_page() will fail, don't use sg lists
512          * in the fc_frame structure.
513          *
514          * The put_page() may be long after the I/O has completed
515          * in the case of FCoE, since the network driver does it
516          * via free_skb().  See the test in free_pages_check().
517          *
518          * Test this case with 'dd </dev/zero >/dev/st0 bs=64k'.
519          */
520         if (using_sg) {
521                 for (sg = scsi_sglist(sc); sg; sg = sg_next(sg)) {
522                         if (page_count(sg_page(sg)) == 0 ||
523                             (sg_page(sg)->flags & (1 << PG_lru |
524                                                    1 << PG_private |
525                                                    1 << PG_locked |
526                                                    1 << PG_active |
527                                                    1 << PG_slab |
528                                                    1 << PG_swapcache |
529                                                    1 << PG_writeback |
530                                                    1 << PG_reserved |
531                                                    1 << PG_buddy))) {
532                                 using_sg = 0;
533                                 break;
534                         }
535                 }
536         }
537         sg = scsi_sglist(sc);
538
539         while (remaining > 0 && sg) {
540                 if (offset >= sg->length) {
541                         offset -= sg->length;
542                         sg = sg_next(sg);
543                         continue;
544                 }
545                 if (!fp) {
546                         tlen = min(t_blen, remaining);
547
548                         /*
549                          * TODO.  Temporary workaround.  fc_seq_send() can't
550                          * handle odd lengths in non-linear skbs.
551                          * This will be the final fragment only.
552                          */
553                         if (tlen % 4)
554                                 using_sg = 0;
555                         if (using_sg) {
556                                 fp = _fc_frame_alloc(lp, 0);
557                                 if (!fp)
558                                         return -ENOMEM;
559                         } else {
560                                 fp = fc_frame_alloc(lp, tlen);
561                                 if (!fp)
562                                         return -ENOMEM;
563
564                                 data = (void *)(fr_hdr(fp)) +
565                                         sizeof(struct fc_frame_header);
566                         }
567                         fh_parm_offset = frame_offset;
568                         fr_max_payload(fp) = fsp->max_payload;
569                 }
570                 sg_bytes = min(tlen, sg->length - offset);
571                 if (using_sg) {
572                         WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags >
573                                 FC_FRAME_SG_LEN);
574                         get_page(sg_page(sg));
575                         skb_fill_page_desc(fp_skb(fp),
576                                            skb_shinfo(fp_skb(fp))->nr_frags,
577                                            sg_page(sg), sg->offset + offset,
578                                            sg_bytes);
579                         fp_skb(fp)->data_len += sg_bytes;
580                         fr_len(fp) += sg_bytes;
581                         fp_skb(fp)->truesize += PAGE_SIZE;
582                 } else {
583                         size_t off = offset + sg->offset;
584
585                         /*
586                          * The scatterlist item may be bigger than PAGE_SIZE,
587                          * but we must not cross pages inside the kmap.
588                          */
589                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
590                                                            (off & ~PAGE_MASK)));
591                         page_addr = kmap_atomic(sg_page(sg) +
592                                                 (off >> PAGE_SHIFT),
593                                                 KM_SOFTIRQ0);
594                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
595                                sg_bytes);
596                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
597                         data += sg_bytes;
598                 }
599                 offset += sg_bytes;
600                 frame_offset += sg_bytes;
601                 tlen -= sg_bytes;
602                 remaining -= sg_bytes;
603
604                 if (tlen)
605                         continue;
606
607                 /*
608                  * Send sequence with transfer sequence initiative in case
609                  * this is last FCP frame of the sequence.
610                  */
611                 if (remaining == 0)
612                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
613
614                 ep = fc_seq_exch(seq);
615                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
616                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
617
618                 /*
619                  * send fragment using for a sequence.
620                  */
621                 error = lp->tt.seq_send(lp, seq, fp);
622                 if (error) {
623                         WARN_ON(1);             /* send error should be rare */
624                         fc_fcp_retry_cmd(fsp);
625                         return 0;
626                 }
627                 fp = NULL;
628         }
629         fsp->xfer_len += seq_blen;      /* premature count? */
630         return 0;
631 }
632
633 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
634 {
635         int ba_done = 1;
636         struct fc_ba_rjt *brp;
637         struct fc_frame_header *fh;
638
639         fh = fc_frame_header_get(fp);
640         switch (fh->fh_r_ctl) {
641         case FC_RCTL_BA_ACC:
642                 break;
643         case FC_RCTL_BA_RJT:
644                 brp = fc_frame_payload_get(fp, sizeof(*brp));
645                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
646                         break;
647                 /* fall thru */
648         default:
649                 /*
650                  * we will let the command timeout
651                  * and scsi-ml recover in this case,
652                  * therefore cleared the ba_done flag.
653                  */
654                 ba_done = 0;
655         }
656
657         if (ba_done) {
658                 fsp->state |= FC_SRB_ABORTED;
659                 fsp->state &= ~FC_SRB_ABORT_PENDING;
660
661                 if (fsp->wait_for_comp)
662                         complete(&fsp->tm_done);
663                 else
664                         fc_fcp_complete_locked(fsp);
665         }
666 }
667
668 /**
669  * fc_fcp_reduce_can_queue() - drop can_queue
670  * @lp: lport to drop queueing for
671  *
672  * If we are getting memory allocation failures, then we may
673  * be trying to execute too many commands. We let the running
674  * commands complete or timeout, then try again with a reduced
675  * can_queue. Eventually we will hit the point where we run
676  * on all reserved structs.
677  */
678 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
679 {
680         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
681         unsigned long flags;
682         int can_queue;
683
684         spin_lock_irqsave(lp->host->host_lock, flags);
685         if (si->throttled)
686                 goto done;
687         si->throttled = 1;
688
689         can_queue = lp->host->can_queue;
690         can_queue >>= 1;
691         if (!can_queue)
692                 can_queue = 1;
693         lp->host->can_queue = can_queue;
694         shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n"
695                      "Reducing can_queue to %d.\n", can_queue);
696 done:
697         spin_unlock_irqrestore(lp->host->host_lock, flags);
698 }
699
700 /**
701  * fc_fcp_recv() - Reveive FCP frames
702  * @seq: The sequence the frame is on
703  * @fp: The FC frame
704  * @arg: The related FCP packet
705  *
706  * Return   : None
707  * Context  : called from Soft IRQ context
708  *            can not called holding list lock
709  */
710 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
711 {
712         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
713         struct fc_lport *lport = fsp->lp;
714         struct fc_frame_header *fh;
715         struct fcp_txrdy *dd;
716         u8 r_ctl;
717         int rc = 0;
718
719         if (IS_ERR(fp))
720                 goto errout;
721
722         fh = fc_frame_header_get(fp);
723         r_ctl = fh->fh_r_ctl;
724
725         if (!(lport->state & LPORT_ST_READY))
726                 goto out;
727         if (fc_fcp_lock_pkt(fsp))
728                 goto out;
729         fsp->last_pkt_time = jiffies;
730
731         if (fh->fh_type == FC_TYPE_BLS) {
732                 fc_fcp_abts_resp(fsp, fp);
733                 goto unlock;
734         }
735
736         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
737                 goto unlock;
738
739         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
740                 /*
741                  * received XFER RDY from the target
742                  * need to send data to the target
743                  */
744                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
745                 dd = fc_frame_payload_get(fp, sizeof(*dd));
746                 WARN_ON(!dd);
747
748                 rc = fc_fcp_send_data(fsp, seq,
749                                       (size_t) ntohl(dd->ft_data_ro),
750                                       (size_t) ntohl(dd->ft_burst_len));
751                 if (!rc)
752                         seq->rec_data = fsp->xfer_len;
753                 else if (rc == -ENOMEM)
754                         fsp->state |= FC_SRB_NOMEM;
755         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
756                 /*
757                  * received a DATA frame
758                  * next we will copy the data to the system buffer
759                  */
760                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
761                 fc_fcp_recv_data(fsp, fp);
762                 seq->rec_data = fsp->xfer_contig_end;
763         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
764                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
765
766                 fc_fcp_resp(fsp, fp);
767         } else {
768                 FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
769         }
770 unlock:
771         fc_fcp_unlock_pkt(fsp);
772 out:
773         fc_frame_free(fp);
774 errout:
775         if (IS_ERR(fp))
776                 fc_fcp_error(fsp, fp);
777         else if (rc == -ENOMEM)
778                 fc_fcp_reduce_can_queue(lport);
779 }
780
781 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
782 {
783         struct fc_frame_header *fh;
784         struct fcp_resp *fc_rp;
785         struct fcp_resp_ext *rp_ex;
786         struct fcp_resp_rsp_info *fc_rp_info;
787         u32 plen;
788         u32 expected_len;
789         u32 respl = 0;
790         u32 snsl = 0;
791         u8 flags = 0;
792
793         plen = fr_len(fp);
794         fh = (struct fc_frame_header *)fr_hdr(fp);
795         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
796                 goto len_err;
797         plen -= sizeof(*fh);
798         fc_rp = (struct fcp_resp *)(fh + 1);
799         fsp->cdb_status = fc_rp->fr_status;
800         flags = fc_rp->fr_flags;
801         fsp->scsi_comp_flags = flags;
802         expected_len = fsp->data_len;
803
804         /* if ddp, update xfer len */
805         fc_fcp_ddp_done(fsp);
806
807         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
808                 rp_ex = (void *)(fc_rp + 1);
809                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
810                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
811                                 goto len_err;
812                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
813                         if (flags & FCP_RSP_LEN_VAL) {
814                                 respl = ntohl(rp_ex->fr_rsp_len);
815                                 if (respl != sizeof(*fc_rp_info))
816                                         goto len_err;
817                                 if (fsp->wait_for_comp) {
818                                         /* Abuse cdb_status for rsp code */
819                                         fsp->cdb_status = fc_rp_info->rsp_code;
820                                         complete(&fsp->tm_done);
821                                         /*
822                                          * tmfs will not have any scsi cmd so
823                                          * exit here
824                                          */
825                                         return;
826                                 } else
827                                         goto err;
828                         }
829                         if (flags & FCP_SNS_LEN_VAL) {
830                                 snsl = ntohl(rp_ex->fr_sns_len);
831                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
832                                         snsl = SCSI_SENSE_BUFFERSIZE;
833                                 memcpy(fsp->cmd->sense_buffer,
834                                        (char *)fc_rp_info + respl, snsl);
835                         }
836                 }
837                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
838                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
839                                 goto len_err;
840                         if (flags & FCP_RESID_UNDER) {
841                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
842                                 /*
843                                  * The cmnd->underflow is the minimum number of
844                                  * bytes that must be transfered for this
845                                  * command.  Provided a sense condition is not
846                                  * present, make sure the actual amount
847                                  * transferred is at least the underflow value
848                                  * or fail.
849                                  */
850                                 if (!(flags & FCP_SNS_LEN_VAL) &&
851                                     (fc_rp->fr_status == 0) &&
852                                     (scsi_bufflen(fsp->cmd) -
853                                      fsp->scsi_resid) < fsp->cmd->underflow)
854                                         goto err;
855                                 expected_len -= fsp->scsi_resid;
856                         } else {
857                                 fsp->status_code = FC_ERROR;
858                         }
859                 }
860         }
861         fsp->state |= FC_SRB_RCV_STATUS;
862
863         /*
864          * Check for missing or extra data frames.
865          */
866         if (unlikely(fsp->xfer_len != expected_len)) {
867                 if (fsp->xfer_len < expected_len) {
868                         /*
869                          * Some data may be queued locally,
870                          * Wait a at least one jiffy to see if it is delivered.
871                          * If this expires without data, we may do SRR.
872                          */
873                         fc_fcp_timer_set(fsp, 2);
874                         return;
875                 }
876                 fsp->status_code = FC_DATA_OVRRUN;
877                 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
878                            "len %x, data len %x\n",
879                            fsp->rport->port_id,
880                            fsp->xfer_len, expected_len, fsp->data_len);
881         }
882         fc_fcp_complete_locked(fsp);
883         return;
884
885 len_err:
886         FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
887                    "snsl %u\n", flags, fr_len(fp), respl, snsl);
888 err:
889         fsp->status_code = FC_ERROR;
890         fc_fcp_complete_locked(fsp);
891 }
892
893 /**
894  * fc_fcp_complete_locked() - complete processing of a fcp packet
895  * @fsp:        fcp packet
896  *
897  * This function may sleep if a timer is pending. The packet lock must be
898  * held, and the host lock must not be held.
899  */
900 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
901 {
902         struct fc_lport *lp = fsp->lp;
903         struct fc_seq *seq;
904         struct fc_exch *ep;
905         u32 f_ctl;
906
907         if (fsp->state & FC_SRB_ABORT_PENDING)
908                 return;
909
910         if (fsp->state & FC_SRB_ABORTED) {
911                 if (!fsp->status_code)
912                         fsp->status_code = FC_CMD_ABORTED;
913         } else {
914                 /*
915                  * Test for transport underrun, independent of response
916                  * underrun status.
917                  */
918                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
919                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
920                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
921                         fsp->status_code = FC_DATA_UNDRUN;
922                         fsp->io_status = 0;
923                 }
924         }
925
926         seq = fsp->seq_ptr;
927         if (seq) {
928                 fsp->seq_ptr = NULL;
929                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
930                         struct fc_frame *conf_frame;
931                         struct fc_seq *csp;
932
933                         csp = lp->tt.seq_start_next(seq);
934                         conf_frame = fc_frame_alloc(fsp->lp, 0);
935                         if (conf_frame) {
936                                 f_ctl = FC_FC_SEQ_INIT;
937                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
938                                 ep = fc_seq_exch(seq);
939                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
940                                                ep->did, ep->sid,
941                                                FC_TYPE_FCP, f_ctl, 0);
942                                 lp->tt.seq_send(lp, csp, conf_frame);
943                         }
944                 }
945                 lp->tt.exch_done(seq);
946         }
947         fc_io_compl(fsp);
948 }
949
950 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
951 {
952         struct fc_lport *lp = fsp->lp;
953
954         if (fsp->seq_ptr) {
955                 lp->tt.exch_done(fsp->seq_ptr);
956                 fsp->seq_ptr = NULL;
957         }
958         fsp->status_code = error;
959 }
960
961 /**
962  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
963  * @lp:         logical port
964  * @id:         target id
965  * @lun:        lun
966  * @error:      fsp status code
967  *
968  * If lun or id is -1, they are ignored.
969  */
970 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
971                                     unsigned int lun, int error)
972 {
973         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
974         struct fc_fcp_pkt *fsp;
975         struct scsi_cmnd *sc_cmd;
976         unsigned long flags;
977
978         spin_lock_irqsave(lp->host->host_lock, flags);
979 restart:
980         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
981                 sc_cmd = fsp->cmd;
982                 if (id != -1 && scmd_id(sc_cmd) != id)
983                         continue;
984
985                 if (lun != -1 && sc_cmd->device->lun != lun)
986                         continue;
987
988                 fc_fcp_pkt_hold(fsp);
989                 spin_unlock_irqrestore(lp->host->host_lock, flags);
990
991                 if (!fc_fcp_lock_pkt(fsp)) {
992                         fc_fcp_cleanup_cmd(fsp, error);
993                         fc_io_compl(fsp);
994                         fc_fcp_unlock_pkt(fsp);
995                 }
996
997                 fc_fcp_pkt_release(fsp);
998                 spin_lock_irqsave(lp->host->host_lock, flags);
999                 /*
1000                  * while we dropped the lock multiple pkts could
1001                  * have been released, so we have to start over.
1002                  */
1003                 goto restart;
1004         }
1005         spin_unlock_irqrestore(lp->host->host_lock, flags);
1006 }
1007
1008 static void fc_fcp_abort_io(struct fc_lport *lp)
1009 {
1010         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
1011 }
1012
1013 /**
1014  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
1015  * @lp:         fc lport
1016  * @fsp:        fc packet.
1017  *
1018  * This is called by upper layer protocol.
1019  * Return   : zero for success and -1 for failure
1020  * Context  : called from queuecommand which can be called from process
1021  *            or scsi soft irq.
1022  * Locks    : called with the host lock and irqs disabled.
1023  */
1024 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1025 {
1026         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
1027         int rc;
1028
1029         fsp->cmd->SCp.ptr = (char *)fsp;
1030         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1031         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1032
1033         int_to_scsilun(fsp->cmd->device->lun,
1034                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1035         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1036         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1037
1038         spin_unlock_irq(lp->host->host_lock);
1039         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
1040         spin_lock_irq(lp->host->host_lock);
1041         if (rc)
1042                 list_del(&fsp->list);
1043
1044         return rc;
1045 }
1046
1047 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1048                            void (*resp)(struct fc_seq *,
1049                                         struct fc_frame *fp,
1050                                         void *arg))
1051 {
1052         struct fc_frame *fp;
1053         struct fc_seq *seq;
1054         struct fc_rport *rport;
1055         struct fc_rport_libfc_priv *rp;
1056         const size_t len = sizeof(fsp->cdb_cmd);
1057         int rc = 0;
1058
1059         if (fc_fcp_lock_pkt(fsp))
1060                 return 0;
1061
1062         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1063         if (!fp) {
1064                 rc = -1;
1065                 goto unlock;
1066         }
1067
1068         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1069         fr_fsp(fp) = fsp;
1070         rport = fsp->rport;
1071         fsp->max_payload = rport->maxframe_size;
1072         rp = rport->dd_data;
1073
1074         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1075                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1076                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1077
1078         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1079         if (!seq) {
1080                 fc_frame_free(fp);
1081                 rc = -1;
1082                 goto unlock;
1083         }
1084         fsp->last_pkt_time = jiffies;
1085         fsp->seq_ptr = seq;
1086         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1087
1088         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1089         fc_fcp_timer_set(fsp,
1090                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1091                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1092 unlock:
1093         fc_fcp_unlock_pkt(fsp);
1094         return rc;
1095 }
1096
1097 /*
1098  * transport error handler
1099  */
1100 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1101 {
1102         int error = PTR_ERR(fp);
1103
1104         if (fc_fcp_lock_pkt(fsp))
1105                 return;
1106
1107         if (error == -FC_EX_CLOSED) {
1108                 fc_fcp_retry_cmd(fsp);
1109                 goto unlock;
1110         }
1111
1112         /*
1113          * clear abort pending, because the lower layer
1114          * decided to force completion.
1115          */
1116         fsp->state &= ~FC_SRB_ABORT_PENDING;
1117         fsp->status_code = FC_CMD_PLOGO;
1118         fc_fcp_complete_locked(fsp);
1119 unlock:
1120         fc_fcp_unlock_pkt(fsp);
1121 }
1122
1123 /*
1124  * Scsi abort handler- calls to send an abort
1125  * and then wait for abort completion
1126  */
1127 static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1128 {
1129         int rc = FAILED;
1130
1131         if (fc_fcp_send_abort(fsp))
1132                 return FAILED;
1133
1134         init_completion(&fsp->tm_done);
1135         fsp->wait_for_comp = 1;
1136
1137         spin_unlock_bh(&fsp->scsi_pkt_lock);
1138         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1139         spin_lock_bh(&fsp->scsi_pkt_lock);
1140         fsp->wait_for_comp = 0;
1141
1142         if (!rc) {
1143                 FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1144                 rc = FAILED;
1145         } else if (fsp->state & FC_SRB_ABORTED) {
1146                 FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1147                 rc = SUCCESS;
1148                 fc_fcp_complete_locked(fsp);
1149         }
1150
1151         return rc;
1152 }
1153
1154 /*
1155  * Retry LUN reset after resource allocation failed.
1156  */
1157 static void fc_lun_reset_send(unsigned long data)
1158 {
1159         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1160         struct fc_lport *lp = fsp->lp;
1161         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1162                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1163                         return;
1164                 if (fc_fcp_lock_pkt(fsp))
1165                         return;
1166                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1167                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1168                 fc_fcp_unlock_pkt(fsp);
1169         }
1170 }
1171
1172 /*
1173  * Scsi device reset handler- send a LUN RESET to the device
1174  * and wait for reset reply
1175  */
1176 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1177                         unsigned int id, unsigned int lun)
1178 {
1179         int rc;
1180
1181         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1182         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1183         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1184
1185         fsp->wait_for_comp = 1;
1186         init_completion(&fsp->tm_done);
1187
1188         fc_lun_reset_send((unsigned long)fsp);
1189
1190         /*
1191          * wait for completion of reset
1192          * after that make sure all commands are terminated
1193          */
1194         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1195
1196         spin_lock_bh(&fsp->scsi_pkt_lock);
1197         fsp->state |= FC_SRB_COMPL;
1198         spin_unlock_bh(&fsp->scsi_pkt_lock);
1199
1200         del_timer_sync(&fsp->timer);
1201
1202         spin_lock_bh(&fsp->scsi_pkt_lock);
1203         if (fsp->seq_ptr) {
1204                 lp->tt.exch_done(fsp->seq_ptr);
1205                 fsp->seq_ptr = NULL;
1206         }
1207         fsp->wait_for_comp = 0;
1208         spin_unlock_bh(&fsp->scsi_pkt_lock);
1209
1210         if (!rc) {
1211                 FC_SCSI_DBG(lp, "lun reset failed\n");
1212                 return FAILED;
1213         }
1214
1215         /* cdb_status holds the tmf's rsp code */
1216         if (fsp->cdb_status != FCP_TMF_CMPL)
1217                 return FAILED;
1218
1219         FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun);
1220         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1221         return SUCCESS;
1222 }
1223
1224 /*
1225  * Task Managment response handler
1226  */
1227 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1228 {
1229         struct fc_fcp_pkt *fsp = arg;
1230         struct fc_frame_header *fh;
1231
1232         if (IS_ERR(fp)) {
1233                 /*
1234                  * If there is an error just let it timeout or wait
1235                  * for TMF to be aborted if it timedout.
1236                  *
1237                  * scsi-eh will escalate for when either happens.
1238                  */
1239                 return;
1240         }
1241
1242         if (fc_fcp_lock_pkt(fsp))
1243                 return;
1244
1245         /*
1246          * raced with eh timeout handler.
1247          */
1248         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1249                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1250                 return;
1251         }
1252
1253         fh = fc_frame_header_get(fp);
1254         if (fh->fh_type != FC_TYPE_BLS)
1255                 fc_fcp_resp(fsp, fp);
1256         fsp->seq_ptr = NULL;
1257         fsp->lp->tt.exch_done(seq);
1258         fc_frame_free(fp);
1259         fc_fcp_unlock_pkt(fsp);
1260 }
1261
1262 static void fc_fcp_cleanup(struct fc_lport *lp)
1263 {
1264         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1265 }
1266
1267 /*
1268  * fc_fcp_timeout: called by OS timer function.
1269  *
1270  * The timer has been inactivated and must be reactivated if desired
1271  * using fc_fcp_timer_set().
1272  *
1273  * Algorithm:
1274  *
1275  * If REC is supported, just issue it, and return.  The REC exchange will
1276  * complete or time out, and recovery can continue at that point.
1277  *
1278  * Otherwise, if the response has been received without all the data,
1279  * it has been ER_TIMEOUT since the response was received.
1280  *
1281  * If the response has not been received,
1282  * we see if data was received recently.  If it has been, we continue waiting,
1283  * otherwise, we abort the command.
1284  */
1285 static void fc_fcp_timeout(unsigned long data)
1286 {
1287         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1288         struct fc_rport *rport = fsp->rport;
1289         struct fc_rport_libfc_priv *rp = rport->dd_data;
1290
1291         if (fc_fcp_lock_pkt(fsp))
1292                 return;
1293
1294         if (fsp->cdb_cmd.fc_tm_flags)
1295                 goto unlock;
1296
1297         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1298
1299         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1300                 fc_fcp_rec(fsp);
1301         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1302                                jiffies))
1303                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1304         else if (fsp->state & FC_SRB_RCV_STATUS)
1305                 fc_fcp_complete_locked(fsp);
1306         else
1307                 fc_timeout_error(fsp);
1308         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1309 unlock:
1310         fc_fcp_unlock_pkt(fsp);
1311 }
1312
1313 /*
1314  * Send a REC ELS request
1315  */
1316 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1317 {
1318         struct fc_lport *lp;
1319         struct fc_frame *fp;
1320         struct fc_rport *rport;
1321         struct fc_rport_libfc_priv *rp;
1322
1323         lp = fsp->lp;
1324         rport = fsp->rport;
1325         rp = rport->dd_data;
1326         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1327                 fsp->status_code = FC_HRD_ERROR;
1328                 fsp->io_status = 0;
1329                 fc_fcp_complete_locked(fsp);
1330                 return;
1331         }
1332         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1333         if (!fp)
1334                 goto retry;
1335
1336         fr_seq(fp) = fsp->seq_ptr;
1337         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1338                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1339                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1340         if (lp->tt.elsct_send(lp, rport, fp, ELS_REC, fc_fcp_rec_resp,
1341                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1342                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1343                 return;
1344         }
1345         fc_frame_free(fp);
1346 retry:
1347         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1348                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1349         else
1350                 fc_timeout_error(fsp);
1351 }
1352
1353 /*
1354  * Receive handler for REC ELS frame
1355  * if it is a reject then let the scsi layer to handle
1356  * the timeout. if it is a LS_ACC then if the io was not completed
1357  * then set the timeout and return otherwise complete the exchange
1358  * and tell the scsi layer to restart the I/O.
1359  */
1360 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1361 {
1362         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1363         struct fc_els_rec_acc *recp;
1364         struct fc_els_ls_rjt *rjt;
1365         u32 e_stat;
1366         u8 opcode;
1367         u32 offset;
1368         enum dma_data_direction data_dir;
1369         enum fc_rctl r_ctl;
1370         struct fc_rport_libfc_priv *rp;
1371
1372         if (IS_ERR(fp)) {
1373                 fc_fcp_rec_error(fsp, fp);
1374                 return;
1375         }
1376
1377         if (fc_fcp_lock_pkt(fsp))
1378                 goto out;
1379
1380         fsp->recov_retry = 0;
1381         opcode = fc_frame_payload_op(fp);
1382         if (opcode == ELS_LS_RJT) {
1383                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1384                 switch (rjt->er_reason) {
1385                 default:
1386                         FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1387                                    "reason %d expl %d\n",
1388                                    fsp->rport->port_id, rjt->er_reason,
1389                                    rjt->er_explan);
1390                         /* fall through */
1391                 case ELS_RJT_UNSUP:
1392                         FC_FCP_DBG(fsp, "device does not support REC\n");
1393                         rp = fsp->rport->dd_data;
1394                         /*
1395                          * if we do not spport RECs or got some bogus
1396                          * reason then resetup timer so we check for
1397                          * making progress.
1398                          */
1399                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1400                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1401                         break;
1402                 case ELS_RJT_LOGIC:
1403                 case ELS_RJT_UNAB:
1404                         /*
1405                          * If no data transfer, the command frame got dropped
1406                          * so we just retry.  If data was transferred, we
1407                          * lost the response but the target has no record,
1408                          * so we abort and retry.
1409                          */
1410                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1411                             fsp->xfer_len == 0) {
1412                                 fc_fcp_retry_cmd(fsp);
1413                                 break;
1414                         }
1415                         fc_timeout_error(fsp);
1416                         break;
1417                 }
1418         } else if (opcode == ELS_LS_ACC) {
1419                 if (fsp->state & FC_SRB_ABORTED)
1420                         goto unlock_out;
1421
1422                 data_dir = fsp->cmd->sc_data_direction;
1423                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1424                 offset = ntohl(recp->reca_fc4value);
1425                 e_stat = ntohl(recp->reca_e_stat);
1426
1427                 if (e_stat & ESB_ST_COMPLETE) {
1428
1429                         /*
1430                          * The exchange is complete.
1431                          *
1432                          * For output, we must've lost the response.
1433                          * For input, all data must've been sent.
1434                          * We lost may have lost the response
1435                          * (and a confirmation was requested) and maybe
1436                          * some data.
1437                          *
1438                          * If all data received, send SRR
1439                          * asking for response.  If partial data received,
1440                          * or gaps, SRR requests data at start of gap.
1441                          * Recovery via SRR relies on in-order-delivery.
1442                          */
1443                         if (data_dir == DMA_TO_DEVICE) {
1444                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1445                         } else if (fsp->xfer_contig_end == offset) {
1446                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1447                         } else {
1448                                 offset = fsp->xfer_contig_end;
1449                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1450                         }
1451                         fc_fcp_srr(fsp, r_ctl, offset);
1452                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1453
1454                         /*
1455                          * The remote port has the initiative, so just
1456                          * keep waiting for it to complete.
1457                          */
1458                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1459                 } else {
1460
1461                         /*
1462                          * The exchange is incomplete, we have seq. initiative.
1463                          * Lost response with requested confirmation,
1464                          * lost confirmation, lost transfer ready or
1465                          * lost write data.
1466                          *
1467                          * For output, if not all data was received, ask
1468                          * for transfer ready to be repeated.
1469                          *
1470                          * If we received or sent all the data, send SRR to
1471                          * request response.
1472                          *
1473                          * If we lost a response, we may have lost some read
1474                          * data as well.
1475                          */
1476                         r_ctl = FC_RCTL_DD_SOL_DATA;
1477                         if (data_dir == DMA_TO_DEVICE) {
1478                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1479                                 if (offset < fsp->data_len)
1480                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1481                         } else if (offset == fsp->xfer_contig_end) {
1482                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1483                         } else if (fsp->xfer_contig_end < offset) {
1484                                 offset = fsp->xfer_contig_end;
1485                         }
1486                         fc_fcp_srr(fsp, r_ctl, offset);
1487                 }
1488         }
1489 unlock_out:
1490         fc_fcp_unlock_pkt(fsp);
1491 out:
1492         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1493         fc_frame_free(fp);
1494 }
1495
1496 /*
1497  * Handle error response or timeout for REC exchange.
1498  */
1499 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1500 {
1501         int error = PTR_ERR(fp);
1502
1503         if (fc_fcp_lock_pkt(fsp))
1504                 goto out;
1505
1506         switch (error) {
1507         case -FC_EX_CLOSED:
1508                 fc_fcp_retry_cmd(fsp);
1509                 break;
1510
1511         default:
1512                 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1513                            fsp, fsp->rport->port_id, error);
1514                 fsp->status_code = FC_CMD_PLOGO;
1515                 /* fall through */
1516
1517         case -FC_EX_TIMEOUT:
1518                 /*
1519                  * Assume REC or LS_ACC was lost.
1520                  * The exchange manager will have aborted REC, so retry.
1521                  */
1522                 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1523                            fsp->rport->port_id, error, fsp->recov_retry,
1524                            FC_MAX_RECOV_RETRY);
1525                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1526                         fc_fcp_rec(fsp);
1527                 else
1528                         fc_timeout_error(fsp);
1529                 break;
1530         }
1531         fc_fcp_unlock_pkt(fsp);
1532 out:
1533         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1534 }
1535
1536 /*
1537  * Time out error routine:
1538  * abort's the I/O close the exchange and
1539  * send completion notification to scsi layer
1540  */
1541 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1542 {
1543         fsp->status_code = FC_CMD_TIME_OUT;
1544         fsp->cdb_status = 0;
1545         fsp->io_status = 0;
1546         /*
1547          * if this fails then we let the scsi command timer fire and
1548          * scsi-ml escalate.
1549          */
1550         fc_fcp_send_abort(fsp);
1551 }
1552
1553 /*
1554  * Sequence retransmission request.
1555  * This is called after receiving status but insufficient data, or
1556  * when expecting status but the request has timed out.
1557  */
1558 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1559 {
1560         struct fc_lport *lp = fsp->lp;
1561         struct fc_rport *rport;
1562         struct fc_rport_libfc_priv *rp;
1563         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1564         struct fc_seq *seq;
1565         struct fcp_srr *srr;
1566         struct fc_frame *fp;
1567         u8 cdb_op;
1568
1569         rport = fsp->rport;
1570         rp = rport->dd_data;
1571         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1572
1573         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1574                 goto retry;                     /* shouldn't happen */
1575         fp = fc_frame_alloc(lp, sizeof(*srr));
1576         if (!fp)
1577                 goto retry;
1578
1579         srr = fc_frame_payload_get(fp, sizeof(*srr));
1580         memset(srr, 0, sizeof(*srr));
1581         srr->srr_op = ELS_SRR;
1582         srr->srr_ox_id = htons(ep->oxid);
1583         srr->srr_rx_id = htons(ep->rxid);
1584         srr->srr_r_ctl = r_ctl;
1585         srr->srr_rel_off = htonl(offset);
1586
1587         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1588                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1589                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1590
1591         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1592                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1593         if (!seq) {
1594                 fc_frame_free(fp);
1595                 goto retry;
1596         }
1597         fsp->recov_seq = seq;
1598         fsp->xfer_len = offset;
1599         fsp->xfer_contig_end = offset;
1600         fsp->state &= ~FC_SRB_RCV_STATUS;
1601         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1602         return;
1603 retry:
1604         fc_fcp_retry_cmd(fsp);
1605 }
1606
1607 /*
1608  * Handle response from SRR.
1609  */
1610 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1611 {
1612         struct fc_fcp_pkt *fsp = arg;
1613         struct fc_frame_header *fh;
1614
1615         if (IS_ERR(fp)) {
1616                 fc_fcp_srr_error(fsp, fp);
1617                 return;
1618         }
1619
1620         if (fc_fcp_lock_pkt(fsp))
1621                 goto out;
1622
1623         fh = fc_frame_header_get(fp);
1624         /*
1625          * BUG? fc_fcp_srr_error calls exch_done which would release
1626          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1627          * then fc_exch_timeout would be sending an abort. The exch_done
1628          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1629          * an abort response though.
1630          */
1631         if (fh->fh_type == FC_TYPE_BLS) {
1632                 fc_fcp_unlock_pkt(fsp);
1633                 return;
1634         }
1635
1636         fsp->recov_seq = NULL;
1637         switch (fc_frame_payload_op(fp)) {
1638         case ELS_LS_ACC:
1639                 fsp->recov_retry = 0;
1640                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1641                 break;
1642         case ELS_LS_RJT:
1643         default:
1644                 fc_timeout_error(fsp);
1645                 break;
1646         }
1647         fc_fcp_unlock_pkt(fsp);
1648         fsp->lp->tt.exch_done(seq);
1649 out:
1650         fc_frame_free(fp);
1651         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1652 }
1653
1654 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1655 {
1656         if (fc_fcp_lock_pkt(fsp))
1657                 goto out;
1658         fsp->lp->tt.exch_done(fsp->recov_seq);
1659         fsp->recov_seq = NULL;
1660         switch (PTR_ERR(fp)) {
1661         case -FC_EX_TIMEOUT:
1662                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1663                         fc_fcp_rec(fsp);
1664                 else
1665                         fc_timeout_error(fsp);
1666                 break;
1667         case -FC_EX_CLOSED:                     /* e.g., link failure */
1668                 /* fall through */
1669         default:
1670                 fc_fcp_retry_cmd(fsp);
1671                 break;
1672         }
1673         fc_fcp_unlock_pkt(fsp);
1674 out:
1675         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1676 }
1677
1678 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1679 {
1680         /* lock ? */
1681         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1682 }
1683
1684 /**
1685  * fc_queuecommand - The queuecommand function of the scsi template
1686  * @cmd:        struct scsi_cmnd to be executed
1687  * @done:       Callback function to be called when cmd is completed
1688  *
1689  * this is the i/o strategy routine, called by the scsi layer
1690  * this routine is called with holding the host_lock.
1691  */
1692 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1693 {
1694         struct fc_lport *lp;
1695         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1696         struct fc_fcp_pkt *fsp;
1697         struct fc_rport_libfc_priv *rp;
1698         int rval;
1699         int rc = 0;
1700         struct fcoe_dev_stats *stats;
1701
1702         lp = shost_priv(sc_cmd->device->host);
1703
1704         rval = fc_remote_port_chkready(rport);
1705         if (rval) {
1706                 sc_cmd->result = rval;
1707                 done(sc_cmd);
1708                 goto out;
1709         }
1710
1711         if (!*(struct fc_remote_port **)rport->dd_data) {
1712                 /*
1713                  * rport is transitioning from blocked/deleted to
1714                  * online
1715                  */
1716                 sc_cmd->result = DID_IMM_RETRY << 16;
1717                 done(sc_cmd);
1718                 goto out;
1719         }
1720
1721         rp = rport->dd_data;
1722
1723         if (!fc_fcp_lport_queue_ready(lp)) {
1724                 rc = SCSI_MLQUEUE_HOST_BUSY;
1725                 goto out;
1726         }
1727
1728         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1729         if (fsp == NULL) {
1730                 rc = SCSI_MLQUEUE_HOST_BUSY;
1731                 goto out;
1732         }
1733
1734         /*
1735          * build the libfc request pkt
1736          */
1737         fsp->cmd = sc_cmd;      /* save the cmd */
1738         fsp->lp = lp;           /* save the softc ptr */
1739         fsp->rport = rport;     /* set the remote port ptr */
1740         sc_cmd->scsi_done = done;
1741
1742         /*
1743          * set up the transfer length
1744          */
1745         fsp->data_len = scsi_bufflen(sc_cmd);
1746         fsp->xfer_len = 0;
1747
1748         /*
1749          * setup the data direction
1750          */
1751         stats = fc_lport_get_stats(lp);
1752         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1753                 fsp->req_flags = FC_SRB_READ;
1754                 stats->InputRequests++;
1755                 stats->InputMegabytes = fsp->data_len;
1756         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1757                 fsp->req_flags = FC_SRB_WRITE;
1758                 stats->OutputRequests++;
1759                 stats->OutputMegabytes = fsp->data_len;
1760         } else {
1761                 fsp->req_flags = 0;
1762                 stats->ControlRequests++;
1763         }
1764
1765         fsp->tgt_flags = rp->flags;
1766
1767         init_timer(&fsp->timer);
1768         fsp->timer.data = (unsigned long)fsp;
1769
1770         /*
1771          * send it to the lower layer
1772          * if we get -1 return then put the request in the pending
1773          * queue.
1774          */
1775         rval = fc_fcp_pkt_send(lp, fsp);
1776         if (rval != 0) {
1777                 fsp->state = FC_SRB_FREE;
1778                 fc_fcp_pkt_release(fsp);
1779                 rc = SCSI_MLQUEUE_HOST_BUSY;
1780         }
1781 out:
1782         return rc;
1783 }
1784 EXPORT_SYMBOL(fc_queuecommand);
1785
1786 /**
1787  * fc_io_compl() -  Handle responses for completed commands
1788  * @fsp:        scsi packet
1789  *
1790  * Translates a error to a Linux SCSI error.
1791  *
1792  * The fcp packet lock must be held when calling.
1793  */
1794 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1795 {
1796         struct fc_fcp_internal *si;
1797         struct scsi_cmnd *sc_cmd;
1798         struct fc_lport *lp;
1799         unsigned long flags;
1800
1801         /* release outstanding ddp context */
1802         fc_fcp_ddp_done(fsp);
1803
1804         fsp->state |= FC_SRB_COMPL;
1805         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1806                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1807                 del_timer_sync(&fsp->timer);
1808                 spin_lock_bh(&fsp->scsi_pkt_lock);
1809         }
1810
1811         lp = fsp->lp;
1812         si = fc_get_scsi_internal(lp);
1813         spin_lock_irqsave(lp->host->host_lock, flags);
1814         if (!fsp->cmd) {
1815                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1816                 return;
1817         }
1818
1819         /*
1820          * if a command timed out while we had to try and throttle IO
1821          * and it is now getting cleaned up, then we are about to
1822          * try again so clear the throttled flag incase we get more
1823          * time outs.
1824          */
1825         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1826                 si->throttled = 0;
1827
1828         sc_cmd = fsp->cmd;
1829         fsp->cmd = NULL;
1830
1831         if (!sc_cmd->SCp.ptr) {
1832                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1833                 return;
1834         }
1835
1836         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1837         switch (fsp->status_code) {
1838         case FC_COMPLETE:
1839                 if (fsp->cdb_status == 0) {
1840                         /*
1841                          * good I/O status
1842                          */
1843                         sc_cmd->result = DID_OK << 16;
1844                         if (fsp->scsi_resid)
1845                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1846                 } else if (fsp->cdb_status == QUEUE_FULL) {
1847                         struct scsi_device *tmp_sdev;
1848                         struct scsi_device *sdev = sc_cmd->device;
1849
1850                         shost_for_each_device(tmp_sdev, sdev->host) {
1851                                 if (tmp_sdev->id != sdev->id)
1852                                         continue;
1853
1854                                 if (tmp_sdev->queue_depth > 1) {
1855                                         scsi_track_queue_full(tmp_sdev,
1856                                                               tmp_sdev->
1857                                                               queue_depth - 1);
1858                                 }
1859                         }
1860                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1861                 } else {
1862                         /*
1863                          * transport level I/O was ok but scsi
1864                          * has non zero status
1865                          */
1866                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1867                 }
1868                 break;
1869         case FC_ERROR:
1870                 sc_cmd->result = DID_ERROR << 16;
1871                 break;
1872         case FC_DATA_UNDRUN:
1873                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1874                         /*
1875                          * scsi status is good but transport level
1876                          * underrun.
1877                          */
1878                         sc_cmd->result = DID_OK << 16;
1879                 } else {
1880                         /*
1881                          * scsi got underrun, this is an error
1882                          */
1883                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1884                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1885                 }
1886                 break;
1887         case FC_DATA_OVRRUN:
1888                 /*
1889                  * overrun is an error
1890                  */
1891                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1892                 break;
1893         case FC_CMD_ABORTED:
1894                 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1895                 break;
1896         case FC_CMD_TIME_OUT:
1897                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1898                 break;
1899         case FC_CMD_RESET:
1900                 sc_cmd->result = (DID_RESET << 16);
1901                 break;
1902         case FC_HRD_ERROR:
1903                 sc_cmd->result = (DID_NO_CONNECT << 16);
1904                 break;
1905         default:
1906                 sc_cmd->result = (DID_ERROR << 16);
1907                 break;
1908         }
1909
1910         list_del(&fsp->list);
1911         sc_cmd->SCp.ptr = NULL;
1912         sc_cmd->scsi_done(sc_cmd);
1913         spin_unlock_irqrestore(lp->host->host_lock, flags);
1914
1915         /* release ref from initial allocation in queue command */
1916         fc_fcp_pkt_release(fsp);
1917 }
1918
1919 /**
1920  * fc_fcp_complete() - complete processing of a fcp packet
1921  * @fsp:        fcp packet
1922  *
1923  * This function may sleep if a fsp timer is pending.
1924  * The host lock must not be held by caller.
1925  */
1926 void fc_fcp_complete(struct fc_fcp_pkt *fsp)
1927 {
1928         if (fc_fcp_lock_pkt(fsp))
1929                 return;
1930
1931         fc_fcp_complete_locked(fsp);
1932         fc_fcp_unlock_pkt(fsp);
1933 }
1934 EXPORT_SYMBOL(fc_fcp_complete);
1935
1936 /**
1937  * fc_eh_abort() - Abort a command
1938  * @sc_cmd:     scsi command to abort
1939  *
1940  * From scsi host template.
1941  * send ABTS to the target device  and wait for the response
1942  * sc_cmd is the pointer to the command to be aborted.
1943  */
1944 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1945 {
1946         struct fc_fcp_pkt *fsp;
1947         struct fc_lport *lp;
1948         int rc = FAILED;
1949         unsigned long flags;
1950
1951         lp = shost_priv(sc_cmd->device->host);
1952         if (lp->state != LPORT_ST_READY)
1953                 return rc;
1954         else if (!lp->link_up)
1955                 return rc;
1956
1957         spin_lock_irqsave(lp->host->host_lock, flags);
1958         fsp = CMD_SP(sc_cmd);
1959         if (!fsp) {
1960                 /* command completed while scsi eh was setting up */
1961                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1962                 return SUCCESS;
1963         }
1964         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1965         fc_fcp_pkt_hold(fsp);
1966         spin_unlock_irqrestore(lp->host->host_lock, flags);
1967
1968         if (fc_fcp_lock_pkt(fsp)) {
1969                 /* completed while we were waiting for timer to be deleted */
1970                 rc = SUCCESS;
1971                 goto release_pkt;
1972         }
1973
1974         rc = fc_fcp_pkt_abort(lp, fsp);
1975         fc_fcp_unlock_pkt(fsp);
1976
1977 release_pkt:
1978         fc_fcp_pkt_release(fsp);
1979         return rc;
1980 }
1981 EXPORT_SYMBOL(fc_eh_abort);
1982
1983 /**
1984  * fc_eh_device_reset() Reset a single LUN
1985  * @sc_cmd:     scsi command
1986  *
1987  * Set from scsi host template to send tm cmd to the target and wait for the
1988  * response.
1989  */
1990 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1991 {
1992         struct fc_lport *lp;
1993         struct fc_fcp_pkt *fsp;
1994         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1995         int rc = FAILED;
1996         struct fc_rport_libfc_priv *rp;
1997         int rval;
1998
1999         rval = fc_remote_port_chkready(rport);
2000         if (rval)
2001                 goto out;
2002
2003         rp = rport->dd_data;
2004         lp = shost_priv(sc_cmd->device->host);
2005
2006         if (lp->state != LPORT_ST_READY)
2007                 return rc;
2008
2009         FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id);
2010
2011         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
2012         if (fsp == NULL) {
2013                 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
2014                 sc_cmd->result = DID_NO_CONNECT << 16;
2015                 goto out;
2016         }
2017
2018         /*
2019          * Build the libfc request pkt. Do not set the scsi cmnd, because
2020          * the sc passed in is not setup for execution like when sent
2021          * through the queuecommand callout.
2022          */
2023         fsp->lp = lp;           /* save the softc ptr */
2024         fsp->rport = rport;     /* set the remote port ptr */
2025
2026         /*
2027          * flush outstanding commands
2028          */
2029         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2030         fsp->state = FC_SRB_FREE;
2031         fc_fcp_pkt_release(fsp);
2032
2033 out:
2034         return rc;
2035 }
2036 EXPORT_SYMBOL(fc_eh_device_reset);
2037
2038 /**
2039  * fc_eh_host_reset() - The reset function will reset the ports on the host.
2040  * @sc_cmd:     scsi command
2041  */
2042 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2043 {
2044         struct Scsi_Host *shost = sc_cmd->device->host;
2045         struct fc_lport *lp = shost_priv(shost);
2046         unsigned long wait_tmo;
2047
2048         FC_SCSI_DBG(lp, "Resetting host\n");
2049
2050         lp->tt.lport_reset(lp);
2051         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2052         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
2053                 msleep(1000);
2054
2055         if (fc_fcp_lport_queue_ready(lp)) {
2056                 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2057                              "on port (%6x)\n", fc_host_port_id(lp->host));
2058                 return SUCCESS;
2059         } else {
2060                 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2061                              "port (%6x) is not ready.\n",
2062                              fc_host_port_id(lp->host));
2063                 return FAILED;
2064         }
2065 }
2066 EXPORT_SYMBOL(fc_eh_host_reset);
2067
2068 /**
2069  * fc_slave_alloc() - configure queue depth
2070  * @sdev:       scsi device
2071  *
2072  * Configures queue depth based on host's cmd_per_len. If not set
2073  * then we use the libfc default.
2074  */
2075 int fc_slave_alloc(struct scsi_device *sdev)
2076 {
2077         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2078         int queue_depth;
2079
2080         if (!rport || fc_remote_port_chkready(rport))
2081                 return -ENXIO;
2082
2083         if (sdev->tagged_supported) {
2084                 if (sdev->host->hostt->cmd_per_lun)
2085                         queue_depth = sdev->host->hostt->cmd_per_lun;
2086                 else
2087                         queue_depth = FC_FCP_DFLT_QUEUE_DEPTH;
2088                 scsi_activate_tcq(sdev, queue_depth);
2089         }
2090         return 0;
2091 }
2092 EXPORT_SYMBOL(fc_slave_alloc);
2093
2094 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
2095 {
2096         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2097         return sdev->queue_depth;
2098 }
2099 EXPORT_SYMBOL(fc_change_queue_depth);
2100
2101 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2102 {
2103         if (sdev->tagged_supported) {
2104                 scsi_set_tag_type(sdev, tag_type);
2105                 if (tag_type)
2106                         scsi_activate_tcq(sdev, sdev->queue_depth);
2107                 else
2108                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2109         } else
2110                 tag_type = 0;
2111
2112         return tag_type;
2113 }
2114 EXPORT_SYMBOL(fc_change_queue_type);
2115
2116 void fc_fcp_destroy(struct fc_lport *lp)
2117 {
2118         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2119
2120         if (!list_empty(&si->scsi_pkt_queue))
2121                 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2122                        "port (%6x)\n", fc_host_port_id(lp->host));
2123
2124         mempool_destroy(si->scsi_pkt_pool);
2125         kfree(si);
2126         lp->scsi_priv = NULL;
2127 }
2128 EXPORT_SYMBOL(fc_fcp_destroy);
2129
2130 int fc_fcp_init(struct fc_lport *lp)
2131 {
2132         int rc;
2133         struct fc_fcp_internal *si;
2134
2135         if (!lp->tt.fcp_cmd_send)
2136                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2137
2138         if (!lp->tt.fcp_cleanup)
2139                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2140
2141         if (!lp->tt.fcp_abort_io)
2142                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2143
2144         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2145         if (!si)
2146                 return -ENOMEM;
2147         lp->scsi_priv = si;
2148         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2149
2150         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2151         if (!si->scsi_pkt_pool) {
2152                 rc = -ENOMEM;
2153                 goto free_internal;
2154         }
2155         return 0;
2156
2157 free_internal:
2158         kfree(si);
2159         return rc;
2160 }
2161 EXPORT_SYMBOL(fc_fcp_init);
2162
2163 static int __init libfc_init(void)
2164 {
2165         int rc;
2166
2167         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2168                                             sizeof(struct fc_fcp_pkt),
2169                                             0, SLAB_HWCACHE_ALIGN, NULL);
2170         if (scsi_pkt_cachep == NULL) {
2171                 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2172                        "module load failed!");
2173                 return -ENOMEM;
2174         }
2175
2176         rc = fc_setup_exch_mgr();
2177         if (rc)
2178                 goto destroy_pkt_cache;
2179
2180         rc = fc_setup_rport();
2181         if (rc)
2182                 goto destroy_em;
2183
2184         return rc;
2185 destroy_em:
2186         fc_destroy_exch_mgr();
2187 destroy_pkt_cache:
2188         kmem_cache_destroy(scsi_pkt_cachep);
2189         return rc;
2190 }
2191
2192 static void __exit libfc_exit(void)
2193 {
2194         kmem_cache_destroy(scsi_pkt_cachep);
2195         fc_destroy_exch_mgr();
2196         fc_destroy_rport();
2197 }
2198
2199 module_init(libfc_init);
2200 module_exit(libfc_exit);