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