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