1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright(c) 2007 Intel Corporation. All rights reserved.
4 * Copyright(c) 2008 Red Hat, Inc. All rights reserved.
5 * Copyright(c) 2008 Mike Christie
6 *
7 * Maintained at www.Open-FCoE.org
8 */
9
10#include <linux/module.h>
11#include <linux/delay.h>
12#include <linux/kernel.h>
13#include <linux/types.h>
14#include <linux/spinlock.h>
15#include <linux/scatterlist.h>
16#include <linux/err.h>
17#include <linux/crc32.h>
18#include <linux/slab.h>
19
20#include <scsi/scsi_tcq.h>
21#include <scsi/scsi.h>
22#include <scsi/scsi_host.h>
23#include <scsi/scsi_device.h>
24#include <scsi/scsi_cmnd.h>
25
26#include <scsi/fc/fc_fc2.h>
27
28#include <scsi/libfc.h>
29
30#include "fc_encode.h"
31#include "fc_libfc.h"
32
33static struct kmem_cache *scsi_pkt_cachep;
34
35/* SRB state definitions */
36#define FC_SRB_FREE 0 /* cmd is free */
37#define FC_SRB_CMD_SENT (1 << 0) /* cmd has been sent */
38#define FC_SRB_RCV_STATUS (1 << 1) /* response has arrived */
39#define FC_SRB_ABORT_PENDING (1 << 2) /* cmd abort sent to device */
40#define FC_SRB_ABORTED (1 << 3) /* abort acknowledged */
41#define FC_SRB_DISCONTIG (1 << 4) /* non-sequential data recvd */
42#define FC_SRB_COMPL (1 << 5) /* fc_io_compl has been run */
43#define FC_SRB_FCP_PROCESSING_TMO (1 << 6) /* timer function processing */
44
45#define FC_SRB_READ (1 << 1)
46#define FC_SRB_WRITE (1 << 0)
47
48static struct libfc_cmd_priv *libfc_priv(struct scsi_cmnd *cmd)
49{
50 return scsi_cmd_priv(cmd);
51}
52
53/**
54 * struct fc_fcp_internal - FCP layer internal data
55 * @scsi_pkt_pool: Memory pool to draw FCP packets from
56 * @scsi_queue_lock: Protects the scsi_pkt_queue
57 * @scsi_pkt_queue: Current FCP packets
58 * @last_can_queue_ramp_down_time: ramp down time
59 * @last_can_queue_ramp_up_time: ramp up time
60 * @max_can_queue: max can_queue size
61 */
62struct fc_fcp_internal {
63 mempool_t *scsi_pkt_pool;
64 spinlock_t scsi_queue_lock;
65 struct list_head scsi_pkt_queue;
66 unsigned long last_can_queue_ramp_down_time;
67 unsigned long last_can_queue_ramp_up_time;
68 int max_can_queue;
69};
70
71#define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
72
73/*
74 * function prototypes
75 * FC scsi I/O related functions
76 */
77static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
78static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
79static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
80static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
81static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
82static void fc_fcp_error(struct fc_fcp_pkt *, struct fc_frame *);
83static void fc_fcp_recovery(struct fc_fcp_pkt *, u8 code);
84static void fc_fcp_timeout(struct timer_list *);
85static void fc_fcp_rec(struct fc_fcp_pkt *);
86static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
87static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
88static void fc_io_compl(struct fc_fcp_pkt *);
89
90static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
91static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
92static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
93
94/*
95 * command status codes
96 */
97#define FC_COMPLETE 0
98#define FC_CMD_ABORTED 1
99#define FC_CMD_RESET 2
100#define 3
101#define FC_SNS_RCV 4
102#define FC_TRANS_ERR 5
103#define FC_DATA_OVRRUN 6
104#define FC_DATA_UNDRUN 7
105#define FC_ERROR 8
106#define FC_HRD_ERROR 9
107#define FC_CRC_ERROR 10
108#define FC_TIMED_OUT 11
109#define FC_TRANS_RESET 12
110
111/*
112 * Error recovery timeout values.
113 */
114#define FC_SCSI_TM_TOV (10 * HZ)
115#define FC_HOST_RESET_TIMEOUT (30 * HZ)
116#define FC_CAN_QUEUE_PERIOD (60 * HZ)
117
118#define FC_MAX_ERROR_CNT 5
119#define FC_MAX_RECOV_RETRY 3
120
121#define FC_FCP_DFLT_QUEUE_DEPTH 32
122
123/**
124 * fc_fcp_pkt_alloc() - Allocate a fcp_pkt
125 * @lport: The local port that the FCP packet is for
126 * @gfp: GFP flags for allocation
127 *
128 * Return value: fcp_pkt structure or null on allocation failure.
129 * Context: Can be called from process context, no lock is required.
130 */
131static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp)
132{
133 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
134 struct fc_fcp_pkt *fsp;
135
136 fsp = mempool_alloc(pool: si->scsi_pkt_pool, gfp_mask: gfp);
137 if (fsp) {
138 memset(fsp, 0, sizeof(*fsp));
139 fsp->lp = lport;
140 fsp->xfer_ddp = FC_XID_UNKNOWN;
141 refcount_set(r: &fsp->ref_cnt, n: 1);
142 timer_setup(&fsp->timer, NULL, 0);
143 INIT_LIST_HEAD(list: &fsp->list);
144 spin_lock_init(&fsp->scsi_pkt_lock);
145 } else {
146 this_cpu_inc(lport->stats->FcpPktAllocFails);
147 }
148 return fsp;
149}
150
151/**
152 * fc_fcp_pkt_release() - Release hold on a fcp_pkt
153 * @fsp: The FCP packet to be released
154 *
155 * Context: Can be called from process or interrupt context,
156 * no lock is required.
157 */
158static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
159{
160 if (refcount_dec_and_test(r: &fsp->ref_cnt)) {
161 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
162
163 mempool_free(element: fsp, pool: si->scsi_pkt_pool);
164 }
165}
166
167/**
168 * fc_fcp_pkt_hold() - Hold a fcp_pkt
169 * @fsp: The FCP packet to be held
170 */
171static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
172{
173 refcount_inc(r: &fsp->ref_cnt);
174}
175
176/**
177 * fc_fcp_pkt_destroy() - Release hold on a fcp_pkt
178 * @seq: The sequence that the FCP packet is on (required by destructor API)
179 * @fsp: The FCP packet to be released
180 *
181 * This routine is called by a destructor callback in the fc_exch_seq_send()
182 * routine of the libfc Transport Template. The 'struct fc_seq' is a required
183 * argument even though it is not used by this routine.
184 *
185 * Context: No locking required.
186 */
187static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
188{
189 fc_fcp_pkt_release(fsp);
190}
191
192/**
193 * fc_fcp_lock_pkt() - Lock a fcp_pkt and increase its reference count
194 * @fsp: The FCP packet to be locked and incremented
195 *
196 * We should only return error if we return a command to SCSI-ml before
197 * getting a response. This can happen in cases where we send a abort, but
198 * do not wait for the response and the abort and command can be passing
199 * each other on the wire/network-layer.
200 *
201 * Note: this function locks the packet and gets a reference to allow
202 * callers to call the completion function while the lock is held and
203 * not have to worry about the packets refcount.
204 *
205 * TODO: Maybe we should just have callers grab/release the lock and
206 * have a function that they call to verify the fsp and grab a ref if
207 * needed.
208 */
209static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
210{
211 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
212 if (fsp->state & FC_SRB_COMPL) {
213 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
214 return -EPERM;
215 }
216
217 fc_fcp_pkt_hold(fsp);
218 return 0;
219}
220
221/**
222 * fc_fcp_unlock_pkt() - Release a fcp_pkt's lock and decrement its
223 * reference count
224 * @fsp: The FCP packet to be unlocked and decremented
225 */
226static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
227{
228 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
229 fc_fcp_pkt_release(fsp);
230}
231
232/**
233 * fc_fcp_timer_set() - Start a timer for a fcp_pkt
234 * @fsp: The FCP packet to start a timer for
235 * @delay: The timeout period in jiffies
236 */
237static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
238{
239 if (!(fsp->state & FC_SRB_COMPL)) {
240 mod_timer(timer: &fsp->timer, expires: jiffies + delay);
241 fsp->timer_delay = delay;
242 }
243}
244
245static void fc_fcp_abort_done(struct fc_fcp_pkt *fsp)
246{
247 fsp->state |= FC_SRB_ABORTED;
248 fsp->state &= ~FC_SRB_ABORT_PENDING;
249
250 if (fsp->wait_for_comp)
251 complete(&fsp->tm_done);
252 else
253 fc_fcp_complete_locked(fsp);
254}
255
256/**
257 * fc_fcp_send_abort() - Send an abort for exchanges associated with a
258 * fcp_pkt
259 * @fsp: The FCP packet to abort exchanges on
260 */
261static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
262{
263 int rc;
264
265 if (!fsp->seq_ptr)
266 return -EINVAL;
267
268 if (fsp->state & FC_SRB_ABORT_PENDING) {
269 FC_FCP_DBG(fsp, "abort already pending\n");
270 return -EBUSY;
271 }
272
273 this_cpu_inc(fsp->lp->stats->FcpPktAborts);
274
275 fsp->state |= FC_SRB_ABORT_PENDING;
276 rc = fc_seq_exch_abort(fsp->seq_ptr, timer_msec: 0);
277 /*
278 * fc_seq_exch_abort() might return -ENXIO if
279 * the sequence is already completed
280 */
281 if (rc == -ENXIO) {
282 fc_fcp_abort_done(fsp);
283 rc = 0;
284 }
285 return rc;
286}
287
288/**
289 * fc_fcp_retry_cmd() - Retry a fcp_pkt
290 * @fsp: The FCP packet to be retried
291 * @status_code: The FCP status code to set
292 *
293 * Sets the status code to be FC_ERROR and then calls
294 * fc_fcp_complete_locked() which in turn calls fc_io_compl().
295 * fc_io_compl() will notify the SCSI-ml that the I/O is done.
296 * The SCSI-ml will retry the command.
297 */
298static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp, int status_code)
299{
300 if (fsp->seq_ptr) {
301 fc_exch_done(sp: fsp->seq_ptr);
302 fsp->seq_ptr = NULL;
303 }
304
305 fsp->state &= ~FC_SRB_ABORT_PENDING;
306 fsp->io_status = 0;
307 fsp->status_code = status_code;
308 fc_fcp_complete_locked(fsp);
309}
310
311/**
312 * fc_fcp_ddp_setup() - Calls a LLD's ddp_setup routine to set up DDP context
313 * @fsp: The FCP packet that will manage the DDP frames
314 * @xid: The XID that will be used for the DDP exchange
315 */
316void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
317{
318 struct fc_lport *lport;
319
320 lport = fsp->lp;
321 if ((fsp->req_flags & FC_SRB_READ) &&
322 (lport->lro_enabled) && (lport->tt.ddp_setup)) {
323 if (lport->tt.ddp_setup(lport, xid, scsi_sglist(cmd: fsp->cmd),
324 scsi_sg_count(cmd: fsp->cmd)))
325 fsp->xfer_ddp = xid;
326 }
327}
328
329/**
330 * fc_fcp_ddp_done() - Calls a LLD's ddp_done routine to release any
331 * DDP related resources for a fcp_pkt
332 * @fsp: The FCP packet that DDP had been used on
333 */
334void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
335{
336 struct fc_lport *lport;
337
338 if (!fsp)
339 return;
340
341 if (fsp->xfer_ddp == FC_XID_UNKNOWN)
342 return;
343
344 lport = fsp->lp;
345 if (lport->tt.ddp_done) {
346 fsp->xfer_len = lport->tt.ddp_done(lport, fsp->xfer_ddp);
347 fsp->xfer_ddp = FC_XID_UNKNOWN;
348 }
349}
350
351/**
352 * fc_fcp_can_queue_ramp_up() - increases can_queue
353 * @lport: lport to ramp up can_queue
354 */
355static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport)
356{
357 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
358 unsigned long flags;
359 int can_queue;
360
361 spin_lock_irqsave(lport->host->host_lock, flags);
362
363 if (si->last_can_queue_ramp_up_time &&
364 (time_before(jiffies, si->last_can_queue_ramp_up_time +
365 FC_CAN_QUEUE_PERIOD)))
366 goto unlock;
367
368 if (time_before(jiffies, si->last_can_queue_ramp_down_time +
369 FC_CAN_QUEUE_PERIOD))
370 goto unlock;
371
372 si->last_can_queue_ramp_up_time = jiffies;
373
374 can_queue = lport->host->can_queue << 1;
375 if (can_queue >= si->max_can_queue) {
376 can_queue = si->max_can_queue;
377 si->last_can_queue_ramp_down_time = 0;
378 }
379 lport->host->can_queue = can_queue;
380 shost_printk(KERN_ERR, lport->host, "libfc: increased "
381 "can_queue to %d.\n", can_queue);
382
383unlock:
384 spin_unlock_irqrestore(lock: lport->host->host_lock, flags);
385}
386
387/**
388 * fc_fcp_can_queue_ramp_down() - reduces can_queue
389 * @lport: lport to reduce can_queue
390 *
391 * If we are getting memory allocation failures, then we may
392 * be trying to execute too many commands. We let the running
393 * commands complete or timeout, then try again with a reduced
394 * can_queue. Eventually we will hit the point where we run
395 * on all reserved structs.
396 */
397static bool fc_fcp_can_queue_ramp_down(struct fc_lport *lport)
398{
399 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
400 unsigned long flags;
401 int can_queue;
402 bool changed = false;
403
404 spin_lock_irqsave(lport->host->host_lock, flags);
405
406 if (si->last_can_queue_ramp_down_time &&
407 (time_before(jiffies, si->last_can_queue_ramp_down_time +
408 FC_CAN_QUEUE_PERIOD)))
409 goto unlock;
410
411 si->last_can_queue_ramp_down_time = jiffies;
412
413 can_queue = lport->host->can_queue;
414 can_queue >>= 1;
415 if (!can_queue)
416 can_queue = 1;
417 lport->host->can_queue = can_queue;
418 changed = true;
419
420unlock:
421 spin_unlock_irqrestore(lock: lport->host->host_lock, flags);
422 return changed;
423}
424
425/*
426 * fc_fcp_frame_alloc() - Allocates fc_frame structure and buffer.
427 * @lport: fc lport struct
428 * @len: payload length
429 *
430 * Allocates fc_frame structure and buffer but if fails to allocate
431 * then reduce can_queue.
432 */
433static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport,
434 size_t len)
435{
436 struct fc_frame *fp;
437
438 fp = fc_frame_alloc(dev: lport, len);
439 if (likely(fp))
440 return fp;
441
442 this_cpu_inc(lport->stats->FcpFrameAllocFails);
443 /* error case */
444 fc_fcp_can_queue_ramp_down(lport);
445 shost_printk(KERN_ERR, lport->host,
446 "libfc: Could not allocate frame, "
447 "reducing can_queue to %d.\n", lport->host->can_queue);
448 return NULL;
449}
450
451/**
452 * get_fsp_rec_tov() - Helper function to get REC_TOV
453 * @fsp: the FCP packet
454 *
455 * Returns rec tov in jiffies as rpriv->e_d_tov + 1 second
456 */
457static inline unsigned int get_fsp_rec_tov(struct fc_fcp_pkt *fsp)
458{
459 struct fc_rport_libfc_priv *rpriv = fsp->rport->dd_data;
460 unsigned int e_d_tov = FC_DEF_E_D_TOV;
461
462 if (rpriv && rpriv->e_d_tov > e_d_tov)
463 e_d_tov = rpriv->e_d_tov;
464 return msecs_to_jiffies(m: e_d_tov) + HZ;
465}
466
467/**
468 * fc_fcp_recv_data() - Handler for receiving SCSI-FCP data from a target
469 * @fsp: The FCP packet the data is on
470 * @fp: The data frame
471 */
472static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
473{
474 struct scsi_cmnd *sc = fsp->cmd;
475 struct fc_lport *lport = fsp->lp;
476 struct fc_frame_header *fh;
477 size_t start_offset;
478 size_t offset;
479 u32 crc;
480 u32 copy_len = 0;
481 size_t len;
482 void *buf;
483 struct scatterlist *sg;
484 u32 nents;
485 u8 host_bcode = FC_COMPLETE;
486
487 fh = fc_frame_header_get(fp);
488 offset = ntohl(fh->fh_parm_offset);
489 start_offset = offset;
490 len = fr_len(fp) - sizeof(*fh);
491 buf = fc_frame_payload_get(fp, len: 0);
492
493 /*
494 * if this I/O is ddped then clear it and initiate recovery since data
495 * frames are expected to be placed directly in that case.
496 *
497 * Indicate error to scsi-ml because something went wrong with the
498 * ddp handling to get us here.
499 */
500 if (fsp->xfer_ddp != FC_XID_UNKNOWN) {
501 fc_fcp_ddp_done(fsp);
502 FC_FCP_DBG(fsp, "DDP I/O in fc_fcp_recv_data set ERROR\n");
503 host_bcode = FC_ERROR;
504 goto err;
505 }
506 if (offset + len > fsp->data_len) {
507 /* this should never happen */
508 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
509 fc_frame_crc_check(fp))
510 goto crc_err;
511 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
512 "data_len %x\n", len, offset, fsp->data_len);
513
514 /* Data is corrupted indicate scsi-ml should retry */
515 host_bcode = FC_DATA_OVRRUN;
516 goto err;
517 }
518 if (offset != fsp->xfer_len)
519 fsp->state |= FC_SRB_DISCONTIG;
520
521 sg = scsi_sglist(cmd: sc);
522 nents = scsi_sg_count(cmd: sc);
523
524 if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) {
525 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, nents: &nents,
526 offset: &offset, NULL);
527 } else {
528 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
529 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, nents: &nents,
530 offset: &offset, crc: &crc);
531 buf = fc_frame_payload_get(fp, len: 0);
532 if (len % 4)
533 crc = crc32(crc, buf + len, 4 - (len % 4));
534
535 if (~crc != le32_to_cpu(fr_crc(fp))) {
536crc_err:
537 this_cpu_inc(lport->stats->ErrorFrames);
538 /* per cpu count, not total count, but OK for limit */
539 if (this_cpu_inc_return(lport->stats->InvalidCRCCount) < FC_MAX_ERROR_CNT)
540 printk(KERN_WARNING "libfc: CRC error on data "
541 "frame for port (%6.6x)\n",
542 lport->port_id);
543 /*
544 * Assume the frame is total garbage.
545 * We may have copied it over the good part
546 * of the buffer.
547 * If so, we need to retry the entire operation.
548 * Otherwise, ignore it.
549 */
550 if (fsp->state & FC_SRB_DISCONTIG) {
551 host_bcode = FC_CRC_ERROR;
552 goto err;
553 }
554 return;
555 }
556 }
557
558 if (fsp->xfer_contig_end == start_offset)
559 fsp->xfer_contig_end += copy_len;
560 fsp->xfer_len += copy_len;
561
562 /*
563 * In the very rare event that this data arrived after the response
564 * and completes the transfer, call the completion handler.
565 */
566 if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
567 fsp->xfer_len == fsp->data_len - fsp->scsi_resid) {
568 FC_FCP_DBG( fsp, "complete out-of-order sequence\n" );
569 fc_fcp_complete_locked(fsp);
570 }
571 return;
572err:
573 fc_fcp_recovery(fsp, code: host_bcode);
574}
575
576/**
577 * fc_fcp_send_data() - Send SCSI data to a target
578 * @fsp: The FCP packet the data is on
579 * @seq: The sequence the data is to be sent on
580 * @offset: The starting offset for this data request
581 * @seq_blen: The burst length for this data request
582 *
583 * Called after receiving a Transfer Ready data descriptor.
584 * If the LLD is capable of sequence offload then send down the
585 * seq_blen amount of data in single frame, otherwise send
586 * multiple frames of the maximum frame payload supported by
587 * the target port.
588 */
589static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
590 size_t offset, size_t seq_blen)
591{
592 struct fc_exch *ep;
593 struct scsi_cmnd *sc;
594 struct scatterlist *sg;
595 struct fc_frame *fp = NULL;
596 struct fc_lport *lport = fsp->lp;
597 struct page *page;
598 size_t remaining;
599 size_t t_blen;
600 size_t tlen;
601 size_t sg_bytes;
602 size_t frame_offset, fh_parm_offset;
603 size_t off;
604 int error;
605 void *data = NULL;
606 void *page_addr;
607 int using_sg = lport->sg_supp;
608 u32 f_ctl;
609
610 WARN_ON(seq_blen <= 0);
611 if (unlikely(offset + seq_blen > fsp->data_len)) {
612 /* this should never happen */
613 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
614 "offset %zx\n", seq_blen, offset);
615 fc_fcp_send_abort(fsp);
616 return 0;
617 } else if (offset != fsp->xfer_len) {
618 /* Out of Order Data Request - no problem, but unexpected. */
619 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
620 "seq_blen %zx offset %zx\n", seq_blen, offset);
621 }
622
623 /*
624 * if LLD is capable of seq_offload then set transport
625 * burst length (t_blen) to seq_blen, otherwise set t_blen
626 * to max FC frame payload previously set in fsp->max_payload.
627 */
628 t_blen = fsp->max_payload;
629 if (lport->seq_offload) {
630 t_blen = min(seq_blen, (size_t)lport->lso_max);
631 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
632 fsp, seq_blen, lport->lso_max, t_blen);
633 }
634
635 if (t_blen > 512)
636 t_blen &= ~(512 - 1); /* round down to block size */
637 sc = fsp->cmd;
638
639 remaining = seq_blen;
640 fh_parm_offset = frame_offset = offset;
641 tlen = 0;
642 seq = fc_seq_start_next(sp: seq);
643 f_ctl = FC_FC_REL_OFF;
644 WARN_ON(!seq);
645
646 sg = scsi_sglist(cmd: sc);
647
648 while (remaining > 0 && sg) {
649 if (offset >= sg->length) {
650 offset -= sg->length;
651 sg = sg_next(sg);
652 continue;
653 }
654 if (!fp) {
655 tlen = min(t_blen, remaining);
656
657 /*
658 * TODO. Temporary workaround. fc_seq_send() can't
659 * handle odd lengths in non-linear skbs.
660 * This will be the final fragment only.
661 */
662 if (tlen % 4)
663 using_sg = 0;
664 fp = fc_frame_alloc(dev: lport, len: using_sg ? 0 : tlen);
665 if (!fp)
666 return -ENOMEM;
667
668 data = fc_frame_header_get(fp) + 1;
669 fh_parm_offset = frame_offset;
670 fr_max_payload(fp) = fsp->max_payload;
671 }
672
673 off = offset + sg->offset;
674 sg_bytes = min(tlen, sg->length - offset);
675 sg_bytes = min(sg_bytes,
676 (size_t) (PAGE_SIZE - (off & ~PAGE_MASK)));
677 page = sg_page(sg) + (off >> PAGE_SHIFT);
678 if (using_sg) {
679 get_page(page);
680 skb_fill_page_desc(fp_skb(fp),
681 skb_shinfo(fp_skb(fp))->nr_frags,
682 page, off: off & ~PAGE_MASK, size: sg_bytes);
683 fp_skb(fp)->data_len += sg_bytes;
684 fr_len(fp) += sg_bytes;
685 fp_skb(fp)->truesize += PAGE_SIZE;
686 } else {
687 /*
688 * The scatterlist item may be bigger than PAGE_SIZE,
689 * but we must not cross pages inside the kmap.
690 */
691 page_addr = kmap_atomic(page);
692 memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
693 sg_bytes);
694 kunmap_atomic(page_addr);
695 data += sg_bytes;
696 }
697 offset += sg_bytes;
698 frame_offset += sg_bytes;
699 tlen -= sg_bytes;
700 remaining -= sg_bytes;
701
702 if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
703 (tlen))
704 continue;
705
706 /*
707 * Send sequence with transfer sequence initiative in case
708 * this is last FCP frame of the sequence.
709 */
710 if (remaining == 0)
711 f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
712
713 ep = fc_seq_exch(seq);
714 fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_DD_SOL_DATA, did: ep->did, sid: ep->sid,
715 type: FC_TYPE_FCP, f_ctl, parm_offset: fh_parm_offset);
716
717 /*
718 * send fragment using for a sequence.
719 */
720 error = fc_seq_send(lport, sp: seq, fp);
721 if (error) {
722 WARN_ON(1); /* send error should be rare */
723 return error;
724 }
725 fp = NULL;
726 }
727 fsp->xfer_len += seq_blen; /* premature count? */
728 return 0;
729}
730
731/**
732 * fc_fcp_abts_resp() - Receive an ABTS response
733 * @fsp: The FCP packet that is being aborted
734 * @fp: The response frame
735 */
736static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
737{
738 int ba_done = 1;
739 struct fc_ba_rjt *brp;
740 struct fc_frame_header *fh;
741
742 fh = fc_frame_header_get(fp);
743 switch (fh->fh_r_ctl) {
744 case FC_RCTL_BA_ACC:
745 break;
746 case FC_RCTL_BA_RJT:
747 brp = fc_frame_payload_get(fp, len: sizeof(*brp));
748 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
749 break;
750 fallthrough;
751 default:
752 /*
753 * we will let the command timeout
754 * and scsi-ml recover in this case,
755 * therefore cleared the ba_done flag.
756 */
757 ba_done = 0;
758 }
759
760 if (ba_done)
761 fc_fcp_abort_done(fsp);
762}
763
764/**
765 * fc_fcp_recv() - Receive an FCP frame
766 * @seq: The sequence the frame is on
767 * @fp: The received frame
768 * @arg: The related FCP packet
769 *
770 * Context: Called from Soft IRQ context. Can not be called
771 * holding the FCP packet list lock.
772 */
773static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
774{
775 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
776 struct fc_lport *lport = fsp->lp;
777 struct fc_frame_header *fh;
778 struct fcp_txrdy *dd;
779 u8 r_ctl;
780 int rc = 0;
781
782 if (IS_ERR(ptr: fp)) {
783 fc_fcp_error(fsp, fp);
784 return;
785 }
786
787 fh = fc_frame_header_get(fp);
788 r_ctl = fh->fh_r_ctl;
789
790 if (lport->state != LPORT_ST_READY) {
791 FC_FCP_DBG(fsp, "lport state %d, ignoring r_ctl %x\n",
792 lport->state, r_ctl);
793 goto out;
794 }
795 if (fc_fcp_lock_pkt(fsp))
796 goto out;
797
798 if (fh->fh_type == FC_TYPE_BLS) {
799 fc_fcp_abts_resp(fsp, fp);
800 goto unlock;
801 }
802
803 if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING)) {
804 FC_FCP_DBG(fsp, "command aborted, ignoring r_ctl %x\n", r_ctl);
805 goto unlock;
806 }
807
808 if (r_ctl == FC_RCTL_DD_DATA_DESC) {
809 /*
810 * received XFER RDY from the target
811 * need to send data to the target
812 */
813 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
814 dd = fc_frame_payload_get(fp, len: sizeof(*dd));
815 WARN_ON(!dd);
816
817 rc = fc_fcp_send_data(fsp, seq,
818 offset: (size_t) ntohl(dd->ft_data_ro),
819 seq_blen: (size_t) ntohl(dd->ft_burst_len));
820 if (!rc)
821 seq->rec_data = fsp->xfer_len;
822 } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
823 /*
824 * received a DATA frame
825 * next we will copy the data to the system buffer
826 */
827 WARN_ON(fr_len(fp) < sizeof(*fh)); /* len may be 0 */
828 fc_fcp_recv_data(fsp, fp);
829 seq->rec_data = fsp->xfer_contig_end;
830 } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
831 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
832
833 fc_fcp_resp(fsp, fp);
834 } else {
835 FC_FCP_DBG(fsp, "unexpected frame. r_ctl %x\n", r_ctl);
836 }
837unlock:
838 fc_fcp_unlock_pkt(fsp);
839out:
840 fc_frame_free(fp);
841}
842
843/**
844 * fc_fcp_resp() - Handler for FCP responses
845 * @fsp: The FCP packet the response is for
846 * @fp: The response frame
847 */
848static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
849{
850 struct fc_frame_header *fh;
851 struct fcp_resp *fc_rp;
852 struct fcp_resp_ext *rp_ex;
853 struct fcp_resp_rsp_info *fc_rp_info;
854 u32 plen;
855 u32 expected_len;
856 u32 respl = 0;
857 u32 snsl = 0;
858 u8 flags = 0;
859
860 plen = fr_len(fp);
861 fh = (struct fc_frame_header *)fr_hdr(fp);
862 if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
863 goto len_err;
864 plen -= sizeof(*fh);
865 fc_rp = (struct fcp_resp *)(fh + 1);
866 fsp->cdb_status = fc_rp->fr_status;
867 flags = fc_rp->fr_flags;
868 fsp->scsi_comp_flags = flags;
869 expected_len = fsp->data_len;
870
871 /* if ddp, update xfer len */
872 fc_fcp_ddp_done(fsp);
873
874 if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
875 rp_ex = (void *)(fc_rp + 1);
876 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
877 if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
878 goto len_err;
879 fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
880 if (flags & FCP_RSP_LEN_VAL) {
881 respl = ntohl(rp_ex->fr_rsp_len);
882 if ((respl != FCP_RESP_RSP_INFO_LEN4) &&
883 (respl != FCP_RESP_RSP_INFO_LEN8))
884 goto len_err;
885 if (fsp->wait_for_comp) {
886 /* Abuse cdb_status for rsp code */
887 fsp->cdb_status = fc_rp_info->rsp_code;
888 complete(&fsp->tm_done);
889 /*
890 * tmfs will not have any scsi cmd so
891 * exit here
892 */
893 return;
894 }
895 }
896 if (flags & FCP_SNS_LEN_VAL) {
897 snsl = ntohl(rp_ex->fr_sns_len);
898 if (snsl > SCSI_SENSE_BUFFERSIZE)
899 snsl = SCSI_SENSE_BUFFERSIZE;
900 memcpy(fsp->cmd->sense_buffer,
901 (char *)fc_rp_info + respl, snsl);
902 }
903 }
904 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
905 if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
906 goto len_err;
907 if (flags & FCP_RESID_UNDER) {
908 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
909 /*
910 * The cmnd->underflow is the minimum number of
911 * bytes that must be transferred for this
912 * command. Provided a sense condition is not
913 * present, make sure the actual amount
914 * transferred is at least the underflow value
915 * or fail.
916 */
917 if (!(flags & FCP_SNS_LEN_VAL) &&
918 (fc_rp->fr_status == 0) &&
919 (scsi_bufflen(cmd: fsp->cmd) -
920 fsp->scsi_resid) < fsp->cmd->underflow)
921 goto err;
922 expected_len -= fsp->scsi_resid;
923 } else {
924 fsp->status_code = FC_ERROR;
925 }
926 }
927 }
928 fsp->state |= FC_SRB_RCV_STATUS;
929
930 /*
931 * Check for missing or extra data frames.
932 */
933 if (unlikely(fsp->cdb_status == SAM_STAT_GOOD &&
934 fsp->xfer_len != expected_len)) {
935 if (fsp->xfer_len < expected_len) {
936 /*
937 * Some data may be queued locally,
938 * Wait a at least one jiffy to see if it is delivered.
939 * If this expires without data, we may do SRR.
940 */
941 if (fsp->lp->qfull) {
942 FC_FCP_DBG(fsp, "tgt %6.6x queue busy retry\n",
943 fsp->rport->port_id);
944 return;
945 }
946 FC_FCP_DBG(fsp, "tgt %6.6x xfer len %zx data underrun "
947 "len %x, data len %x\n",
948 fsp->rport->port_id,
949 fsp->xfer_len, expected_len, fsp->data_len);
950 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
951 return;
952 }
953 fsp->status_code = FC_DATA_OVRRUN;
954 FC_FCP_DBG(fsp, "tgt %6.6x xfer len %zx greater than expected, "
955 "len %x, data len %x\n",
956 fsp->rport->port_id,
957 fsp->xfer_len, expected_len, fsp->data_len);
958 }
959 fc_fcp_complete_locked(fsp);
960 return;
961
962len_err:
963 FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
964 "snsl %u\n", flags, fr_len(fp), respl, snsl);
965err:
966 fsp->status_code = FC_ERROR;
967 fc_fcp_complete_locked(fsp);
968}
969
970/**
971 * fc_fcp_complete_locked() - Complete processing of a fcp_pkt with the
972 * fcp_pkt lock held
973 * @fsp: The FCP packet to be completed
974 *
975 * This function may sleep if a timer is pending. The packet lock must be
976 * held, and the host lock must not be held.
977 */
978static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
979{
980 struct fc_lport *lport = fsp->lp;
981 struct fc_seq *seq;
982 struct fc_exch *ep;
983 u32 f_ctl;
984
985 if (fsp->state & FC_SRB_ABORT_PENDING)
986 return;
987
988 if (fsp->state & FC_SRB_ABORTED) {
989 if (!fsp->status_code)
990 fsp->status_code = FC_CMD_ABORTED;
991 } else {
992 /*
993 * Test for transport underrun, independent of response
994 * underrun status.
995 */
996 if (fsp->cdb_status == SAM_STAT_GOOD &&
997 fsp->xfer_len < fsp->data_len && !fsp->io_status &&
998 (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
999 fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
1000 FC_FCP_DBG(fsp, "data underrun, xfer %zx data %x\n",
1001 fsp->xfer_len, fsp->data_len);
1002 fsp->status_code = FC_DATA_UNDRUN;
1003 }
1004 }
1005
1006 seq = fsp->seq_ptr;
1007 if (seq) {
1008 fsp->seq_ptr = NULL;
1009 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
1010 struct fc_frame *conf_frame;
1011 struct fc_seq *csp;
1012
1013 csp = fc_seq_start_next(sp: seq);
1014 conf_frame = fc_fcp_frame_alloc(lport: fsp->lp, len: 0);
1015 if (conf_frame) {
1016 f_ctl = FC_FC_SEQ_INIT;
1017 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1018 ep = fc_seq_exch(seq);
1019 fc_fill_fc_hdr(fp: conf_frame, r_ctl: FC_RCTL_DD_SOL_CTL,
1020 did: ep->did, sid: ep->sid,
1021 type: FC_TYPE_FCP, f_ctl, parm_offset: 0);
1022 fc_seq_send(lport, sp: csp, fp: conf_frame);
1023 }
1024 }
1025 fc_exch_done(sp: seq);
1026 }
1027 /*
1028 * Some resets driven by SCSI are not I/Os and do not have
1029 * SCSI commands associated with the requests. We should not
1030 * call I/O completion if we do not have a SCSI command.
1031 */
1032 if (fsp->cmd)
1033 fc_io_compl(fsp);
1034}
1035
1036/**
1037 * fc_fcp_cleanup_cmd() - Cancel the active exchange on a fcp_pkt
1038 * @fsp: The FCP packet whose exchanges should be canceled
1039 * @error: The reason for the cancellation
1040 */
1041static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
1042{
1043 if (fsp->seq_ptr) {
1044 fc_exch_done(sp: fsp->seq_ptr);
1045 fsp->seq_ptr = NULL;
1046 }
1047 fsp->status_code = error;
1048}
1049
1050/**
1051 * fc_fcp_cleanup_each_cmd() - Cancel all exchanges on a local port
1052 * @lport: The local port whose exchanges should be canceled
1053 * @id: The target's ID
1054 * @lun: The LUN
1055 * @error: The reason for cancellation
1056 *
1057 * If lun or id is -1, they are ignored.
1058 */
1059static void fc_fcp_cleanup_each_cmd(struct fc_lport *lport, unsigned int id,
1060 unsigned int lun, int error)
1061{
1062 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1063 struct fc_fcp_pkt *fsp;
1064 struct scsi_cmnd *sc_cmd;
1065 unsigned long flags;
1066
1067 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1068restart:
1069 list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
1070 sc_cmd = fsp->cmd;
1071 if (id != -1 && scmd_id(sc_cmd) != id)
1072 continue;
1073
1074 if (lun != -1 && sc_cmd->device->lun != lun)
1075 continue;
1076
1077 fc_fcp_pkt_hold(fsp);
1078 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
1079
1080 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1081 if (!(fsp->state & FC_SRB_COMPL)) {
1082 fsp->state |= FC_SRB_COMPL;
1083 /*
1084 * TODO: dropping scsi_pkt_lock and then reacquiring
1085 * again around fc_fcp_cleanup_cmd() is required,
1086 * since fc_fcp_cleanup_cmd() calls into
1087 * fc_seq_set_resp() and that func preempts cpu using
1088 * schedule. May be schedule and related code should be
1089 * removed instead of unlocking here to avoid scheduling
1090 * while atomic bug.
1091 */
1092 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1093
1094 fc_fcp_cleanup_cmd(fsp, error);
1095
1096 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1097 fc_io_compl(fsp);
1098 }
1099 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1100
1101 fc_fcp_pkt_release(fsp);
1102 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1103 /*
1104 * while we dropped the lock multiple pkts could
1105 * have been released, so we have to start over.
1106 */
1107 goto restart;
1108 }
1109 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
1110}
1111
1112/**
1113 * fc_fcp_abort_io() - Abort all FCP-SCSI exchanges on a local port
1114 * @lport: The local port whose exchanges are to be aborted
1115 */
1116static void fc_fcp_abort_io(struct fc_lport *lport)
1117{
1118 fc_fcp_cleanup_each_cmd(lport, id: -1, lun: -1, FC_HRD_ERROR);
1119}
1120
1121/**
1122 * fc_fcp_pkt_send() - Send a fcp_pkt
1123 * @lport: The local port to send the FCP packet on
1124 * @fsp: The FCP packet to send
1125 *
1126 * Return: Zero for success and -1 for failure
1127 * Locks: Called without locks held
1128 */
1129static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
1130{
1131 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1132 unsigned long flags;
1133 int rc;
1134
1135 libfc_priv(cmd: fsp->cmd)->fsp = fsp;
1136 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1137 fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1138
1139 int_to_scsilun(fsp->cmd->device->lun, &fsp->cdb_cmd.fc_lun);
1140 memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1141
1142 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1143 list_add_tail(new: &fsp->list, head: &si->scsi_pkt_queue);
1144 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
1145 rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv);
1146 if (unlikely(rc)) {
1147 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1148 libfc_priv(cmd: fsp->cmd)->fsp = NULL;
1149 list_del(entry: &fsp->list);
1150 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
1151 }
1152
1153 return rc;
1154}
1155
1156/**
1157 * fc_fcp_cmd_send() - Send a FCP command
1158 * @lport: The local port to send the command on
1159 * @fsp: The FCP packet the command is on
1160 * @resp: The handler for the response
1161 */
1162static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1163 void (*resp)(struct fc_seq *,
1164 struct fc_frame *fp,
1165 void *arg))
1166{
1167 struct fc_frame *fp;
1168 struct fc_seq *seq;
1169 struct fc_rport *rport;
1170 struct fc_rport_libfc_priv *rpriv;
1171 const size_t len = sizeof(fsp->cdb_cmd);
1172 int rc = 0;
1173
1174 if (fc_fcp_lock_pkt(fsp))
1175 return 0;
1176
1177 fp = fc_fcp_frame_alloc(lport, len: sizeof(fsp->cdb_cmd));
1178 if (!fp) {
1179 rc = -1;
1180 goto unlock;
1181 }
1182
1183 memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1184 fr_fsp(fp) = fsp;
1185 rport = fsp->rport;
1186 fsp->max_payload = rport->maxframe_size;
1187 rpriv = rport->dd_data;
1188
1189 fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_DD_UNSOL_CMD, did: rport->port_id,
1190 sid: rpriv->local_port->port_id, type: FC_TYPE_FCP,
1191 FC_FCTL_REQ, parm_offset: 0);
1192
1193 seq = fc_exch_seq_send(lport, fp, resp, destructor: fc_fcp_pkt_destroy, arg: fsp, timer_msec: 0);
1194 if (!seq) {
1195 rc = -1;
1196 goto unlock;
1197 }
1198 fsp->seq_ptr = seq;
1199 fc_fcp_pkt_hold(fsp); /* hold for fc_fcp_pkt_destroy */
1200
1201 fsp->timer.function = fc_fcp_timeout;
1202 if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
1203 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
1204
1205unlock:
1206 fc_fcp_unlock_pkt(fsp);
1207 return rc;
1208}
1209
1210/**
1211 * fc_fcp_error() - Handler for FCP layer errors
1212 * @fsp: The FCP packet the error is on
1213 * @fp: The frame that has errored
1214 */
1215static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1216{
1217 int error = PTR_ERR(ptr: fp);
1218
1219 if (fc_fcp_lock_pkt(fsp))
1220 return;
1221
1222 if (error == -FC_EX_CLOSED) {
1223 fc_fcp_retry_cmd(fsp, FC_ERROR);
1224 goto unlock;
1225 }
1226
1227 /*
1228 * clear abort pending, because the lower layer
1229 * decided to force completion.
1230 */
1231 fsp->state &= ~FC_SRB_ABORT_PENDING;
1232 fsp->status_code = FC_CMD_PLOGO;
1233 fc_fcp_complete_locked(fsp);
1234unlock:
1235 fc_fcp_unlock_pkt(fsp);
1236}
1237
1238/**
1239 * fc_fcp_pkt_abort() - Abort a fcp_pkt
1240 * @fsp: The FCP packet to abort on
1241 *
1242 * Called to send an abort and then wait for abort completion
1243 */
1244static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1245{
1246 int rc = FAILED;
1247 unsigned long ticks_left;
1248
1249 FC_FCP_DBG(fsp, "pkt abort state %x\n", fsp->state);
1250 if (fc_fcp_send_abort(fsp)) {
1251 FC_FCP_DBG(fsp, "failed to send abort\n");
1252 return FAILED;
1253 }
1254
1255 if (fsp->state & FC_SRB_ABORTED) {
1256 FC_FCP_DBG(fsp, "target abort cmd completed\n");
1257 return SUCCESS;
1258 }
1259
1260 init_completion(x: &fsp->tm_done);
1261 fsp->wait_for_comp = 1;
1262
1263 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1264 ticks_left = wait_for_completion_timeout(x: &fsp->tm_done,
1265 FC_SCSI_TM_TOV);
1266 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1267 fsp->wait_for_comp = 0;
1268
1269 if (!ticks_left) {
1270 FC_FCP_DBG(fsp, "target abort cmd failed\n");
1271 } else if (fsp->state & FC_SRB_ABORTED) {
1272 FC_FCP_DBG(fsp, "target abort cmd passed\n");
1273 rc = SUCCESS;
1274 fc_fcp_complete_locked(fsp);
1275 }
1276
1277 return rc;
1278}
1279
1280/**
1281 * fc_lun_reset_send() - Send LUN reset command
1282 * @t: Timer context used to fetch the FSP packet
1283 */
1284static void fc_lun_reset_send(struct timer_list *t)
1285{
1286 struct fc_fcp_pkt *fsp = from_timer(fsp, t, timer);
1287 struct fc_lport *lport = fsp->lp;
1288
1289 if (lport->tt.fcp_cmd_send(lport, fsp, fc_tm_done)) {
1290 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1291 return;
1292 if (fc_fcp_lock_pkt(fsp))
1293 return;
1294 fsp->timer.function = fc_lun_reset_send;
1295 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
1296 fc_fcp_unlock_pkt(fsp);
1297 }
1298}
1299
1300/**
1301 * fc_lun_reset() - Send a LUN RESET command to a device
1302 * and wait for the reply
1303 * @lport: The local port to sent the command on
1304 * @fsp: The FCP packet that identifies the LUN to be reset
1305 * @id: The SCSI command ID
1306 * @lun: The LUN ID to be reset
1307 */
1308static int fc_lun_reset(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1309 unsigned int id, unsigned int lun)
1310{
1311 int rc;
1312
1313 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1314 fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1315 int_to_scsilun(lun, &fsp->cdb_cmd.fc_lun);
1316
1317 fsp->wait_for_comp = 1;
1318 init_completion(x: &fsp->tm_done);
1319
1320 fc_lun_reset_send(t: &fsp->timer);
1321
1322 /*
1323 * wait for completion of reset
1324 * after that make sure all commands are terminated
1325 */
1326 rc = wait_for_completion_timeout(x: &fsp->tm_done, FC_SCSI_TM_TOV);
1327
1328 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1329 fsp->state |= FC_SRB_COMPL;
1330 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1331
1332 del_timer_sync(timer: &fsp->timer);
1333
1334 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1335 if (fsp->seq_ptr) {
1336 fc_exch_done(sp: fsp->seq_ptr);
1337 fsp->seq_ptr = NULL;
1338 }
1339 fsp->wait_for_comp = 0;
1340 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1341
1342 if (!rc) {
1343 FC_SCSI_DBG(lport, "lun reset failed\n");
1344 return FAILED;
1345 }
1346
1347 /* cdb_status holds the tmf's rsp code */
1348 if (fsp->cdb_status != FCP_TMF_CMPL)
1349 return FAILED;
1350
1351 FC_SCSI_DBG(lport, "lun reset to lun %u completed\n", lun);
1352 fc_fcp_cleanup_each_cmd(lport, id, lun, FC_CMD_ABORTED);
1353 return SUCCESS;
1354}
1355
1356/**
1357 * fc_tm_done() - Task Management response handler
1358 * @seq: The sequence that the response is on
1359 * @fp: The response frame
1360 * @arg: The FCP packet the response is for
1361 */
1362static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1363{
1364 struct fc_fcp_pkt *fsp = arg;
1365 struct fc_frame_header *fh;
1366
1367 if (IS_ERR(ptr: fp)) {
1368 /*
1369 * If there is an error just let it timeout or wait
1370 * for TMF to be aborted if it timedout.
1371 *
1372 * scsi-eh will escalate for when either happens.
1373 */
1374 return;
1375 }
1376
1377 if (fc_fcp_lock_pkt(fsp))
1378 goto out;
1379
1380 /*
1381 * raced with eh timeout handler.
1382 */
1383 if (!fsp->seq_ptr || !fsp->wait_for_comp)
1384 goto out_unlock;
1385
1386 fh = fc_frame_header_get(fp);
1387 if (fh->fh_type != FC_TYPE_BLS)
1388 fc_fcp_resp(fsp, fp);
1389 fsp->seq_ptr = NULL;
1390 fc_exch_done(sp: seq);
1391out_unlock:
1392 fc_fcp_unlock_pkt(fsp);
1393out:
1394 fc_frame_free(fp);
1395}
1396
1397/**
1398 * fc_fcp_cleanup() - Cleanup all FCP exchanges on a local port
1399 * @lport: The local port to be cleaned up
1400 */
1401static void fc_fcp_cleanup(struct fc_lport *lport)
1402{
1403 fc_fcp_cleanup_each_cmd(lport, id: -1, lun: -1, FC_ERROR);
1404}
1405
1406/**
1407 * fc_fcp_timeout() - Handler for fcp_pkt timeouts
1408 * @t: Timer context used to fetch the FSP packet
1409 *
1410 * If REC is supported then just issue it and return. The REC exchange will
1411 * complete or time out and recovery can continue at that point. Otherwise,
1412 * if the response has been received without all the data it has been
1413 * ER_TIMEOUT since the response was received. If the response has not been
1414 * received we see if data was received recently. If it has been then we
1415 * continue waiting, otherwise, we abort the command.
1416 */
1417static void fc_fcp_timeout(struct timer_list *t)
1418{
1419 struct fc_fcp_pkt *fsp = from_timer(fsp, t, timer);
1420 struct fc_rport *rport = fsp->rport;
1421 struct fc_rport_libfc_priv *rpriv = rport->dd_data;
1422
1423 if (fc_fcp_lock_pkt(fsp))
1424 return;
1425
1426 if (fsp->cdb_cmd.fc_tm_flags)
1427 goto unlock;
1428
1429 if (fsp->lp->qfull) {
1430 FC_FCP_DBG(fsp, "fcp timeout, resetting timer delay %d\n",
1431 fsp->timer_delay);
1432 fsp->timer.function = fc_fcp_timeout;
1433 fc_fcp_timer_set(fsp, delay: fsp->timer_delay);
1434 goto unlock;
1435 }
1436 FC_FCP_DBG(fsp, "fcp timeout, delay %d flags %x state %x\n",
1437 fsp->timer_delay, rpriv->flags, fsp->state);
1438 fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1439
1440 if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
1441 fc_fcp_rec(fsp);
1442 else if (fsp->state & FC_SRB_RCV_STATUS)
1443 fc_fcp_complete_locked(fsp);
1444 else
1445 fc_fcp_recovery(fsp, FC_TIMED_OUT);
1446 fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1447unlock:
1448 fc_fcp_unlock_pkt(fsp);
1449}
1450
1451/**
1452 * fc_fcp_rec() - Send a REC ELS request
1453 * @fsp: The FCP packet to send the REC request on
1454 */
1455static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1456{
1457 struct fc_lport *lport;
1458 struct fc_frame *fp;
1459 struct fc_rport *rport;
1460 struct fc_rport_libfc_priv *rpriv;
1461
1462 lport = fsp->lp;
1463 rport = fsp->rport;
1464 rpriv = rport->dd_data;
1465 if (!fsp->seq_ptr || rpriv->rp_state != RPORT_ST_READY) {
1466 fsp->status_code = FC_HRD_ERROR;
1467 fsp->io_status = 0;
1468 fc_fcp_complete_locked(fsp);
1469 return;
1470 }
1471
1472 fp = fc_fcp_frame_alloc(lport, len: sizeof(struct fc_els_rec));
1473 if (!fp)
1474 goto retry;
1475
1476 fr_seq(fp) = fsp->seq_ptr;
1477 fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_ELS_REQ, did: rport->port_id,
1478 sid: rpriv->local_port->port_id, type: FC_TYPE_ELS,
1479 FC_FCTL_REQ, parm_offset: 0);
1480 if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC,
1481 fc_fcp_rec_resp, fsp,
1482 2 * lport->r_a_tov)) {
1483 fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */
1484 return;
1485 }
1486retry:
1487 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1488 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
1489 else
1490 fc_fcp_recovery(fsp, FC_TIMED_OUT);
1491}
1492
1493/**
1494 * fc_fcp_rec_resp() - Handler for REC ELS responses
1495 * @seq: The sequence the response is on
1496 * @fp: The response frame
1497 * @arg: The FCP packet the response is on
1498 *
1499 * If the response is a reject then the scsi layer will handle
1500 * the timeout. If the response is a LS_ACC then if the I/O was not completed
1501 * set the timeout and return. If the I/O was completed then complete the
1502 * exchange and tell the SCSI layer.
1503 */
1504static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1505{
1506 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1507 struct fc_els_rec_acc *recp;
1508 struct fc_els_ls_rjt *rjt;
1509 u32 e_stat;
1510 u8 opcode;
1511 u32 offset;
1512 enum dma_data_direction data_dir;
1513 enum fc_rctl r_ctl;
1514 struct fc_rport_libfc_priv *rpriv;
1515
1516 if (IS_ERR(ptr: fp)) {
1517 fc_fcp_rec_error(fsp, fp);
1518 return;
1519 }
1520
1521 if (fc_fcp_lock_pkt(fsp))
1522 goto out;
1523
1524 fsp->recov_retry = 0;
1525 opcode = fc_frame_payload_op(fp);
1526 if (opcode == ELS_LS_RJT) {
1527 rjt = fc_frame_payload_get(fp, len: sizeof(*rjt));
1528 switch (rjt->er_reason) {
1529 default:
1530 FC_FCP_DBG(fsp,
1531 "device %x invalid REC reject %d/%d\n",
1532 fsp->rport->port_id, rjt->er_reason,
1533 rjt->er_explan);
1534 fallthrough;
1535 case ELS_RJT_UNSUP:
1536 FC_FCP_DBG(fsp, "device does not support REC\n");
1537 rpriv = fsp->rport->dd_data;
1538 /*
1539 * if we do not spport RECs or got some bogus
1540 * reason then resetup timer so we check for
1541 * making progress.
1542 */
1543 rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1544 break;
1545 case ELS_RJT_LOGIC:
1546 case ELS_RJT_UNAB:
1547 FC_FCP_DBG(fsp, "device %x REC reject %d/%d\n",
1548 fsp->rport->port_id, rjt->er_reason,
1549 rjt->er_explan);
1550 /*
1551 * If response got lost or is stuck in the
1552 * queue somewhere we have no idea if and when
1553 * the response will be received. So quarantine
1554 * the xid and retry the command.
1555 */
1556 if (rjt->er_explan == ELS_EXPL_OXID_RXID) {
1557 struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1558 ep->state |= FC_EX_QUARANTINE;
1559 fsp->state |= FC_SRB_ABORTED;
1560 fc_fcp_retry_cmd(fsp, FC_TRANS_RESET);
1561 break;
1562 }
1563 fc_fcp_recovery(fsp, FC_TRANS_RESET);
1564 break;
1565 }
1566 } else if (opcode == ELS_LS_ACC) {
1567 if (fsp->state & FC_SRB_ABORTED)
1568 goto unlock_out;
1569
1570 data_dir = fsp->cmd->sc_data_direction;
1571 recp = fc_frame_payload_get(fp, len: sizeof(*recp));
1572 offset = ntohl(recp->reca_fc4value);
1573 e_stat = ntohl(recp->reca_e_stat);
1574
1575 if (e_stat & ESB_ST_COMPLETE) {
1576
1577 /*
1578 * The exchange is complete.
1579 *
1580 * For output, we must've lost the response.
1581 * For input, all data must've been sent.
1582 * We lost may have lost the response
1583 * (and a confirmation was requested) and maybe
1584 * some data.
1585 *
1586 * If all data received, send SRR
1587 * asking for response. If partial data received,
1588 * or gaps, SRR requests data at start of gap.
1589 * Recovery via SRR relies on in-order-delivery.
1590 */
1591 if (data_dir == DMA_TO_DEVICE) {
1592 r_ctl = FC_RCTL_DD_CMD_STATUS;
1593 } else if (fsp->xfer_contig_end == offset) {
1594 r_ctl = FC_RCTL_DD_CMD_STATUS;
1595 } else {
1596 offset = fsp->xfer_contig_end;
1597 r_ctl = FC_RCTL_DD_SOL_DATA;
1598 }
1599 fc_fcp_srr(fsp, r_ctl, offset);
1600 } else if (e_stat & ESB_ST_SEQ_INIT) {
1601 /*
1602 * The remote port has the initiative, so just
1603 * keep waiting for it to complete.
1604 */
1605 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
1606 } else {
1607
1608 /*
1609 * The exchange is incomplete, we have seq. initiative.
1610 * Lost response with requested confirmation,
1611 * lost confirmation, lost transfer ready or
1612 * lost write data.
1613 *
1614 * For output, if not all data was received, ask
1615 * for transfer ready to be repeated.
1616 *
1617 * If we received or sent all the data, send SRR to
1618 * request response.
1619 *
1620 * If we lost a response, we may have lost some read
1621 * data as well.
1622 */
1623 r_ctl = FC_RCTL_DD_SOL_DATA;
1624 if (data_dir == DMA_TO_DEVICE) {
1625 r_ctl = FC_RCTL_DD_CMD_STATUS;
1626 if (offset < fsp->data_len)
1627 r_ctl = FC_RCTL_DD_DATA_DESC;
1628 } else if (offset == fsp->xfer_contig_end) {
1629 r_ctl = FC_RCTL_DD_CMD_STATUS;
1630 } else if (fsp->xfer_contig_end < offset) {
1631 offset = fsp->xfer_contig_end;
1632 }
1633 fc_fcp_srr(fsp, r_ctl, offset);
1634 }
1635 }
1636unlock_out:
1637 fc_fcp_unlock_pkt(fsp);
1638out:
1639 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1640 fc_frame_free(fp);
1641}
1642
1643/**
1644 * fc_fcp_rec_error() - Handler for REC errors
1645 * @fsp: The FCP packet the error is on
1646 * @fp: The REC frame
1647 */
1648static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1649{
1650 int error = PTR_ERR(ptr: fp);
1651
1652 if (fc_fcp_lock_pkt(fsp))
1653 goto out;
1654
1655 switch (error) {
1656 case -FC_EX_CLOSED:
1657 FC_FCP_DBG(fsp, "REC %p fid %6.6x exchange closed\n",
1658 fsp, fsp->rport->port_id);
1659 fc_fcp_retry_cmd(fsp, FC_ERROR);
1660 break;
1661
1662 default:
1663 FC_FCP_DBG(fsp, "REC %p fid %6.6x error unexpected error %d\n",
1664 fsp, fsp->rport->port_id, error);
1665 fsp->status_code = FC_CMD_PLOGO;
1666 fallthrough;
1667
1668 case -FC_EX_TIMEOUT:
1669 /*
1670 * Assume REC or LS_ACC was lost.
1671 * The exchange manager will have aborted REC, so retry.
1672 */
1673 FC_FCP_DBG(fsp, "REC %p fid %6.6x exchange timeout retry %d/%d\n",
1674 fsp, fsp->rport->port_id, fsp->recov_retry,
1675 FC_MAX_RECOV_RETRY);
1676 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1677 fc_fcp_rec(fsp);
1678 else
1679 fc_fcp_recovery(fsp, FC_TIMED_OUT);
1680 break;
1681 }
1682 fc_fcp_unlock_pkt(fsp);
1683out:
1684 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1685}
1686
1687/**
1688 * fc_fcp_recovery() - Handler for fcp_pkt recovery
1689 * @fsp: The FCP pkt that needs to be aborted
1690 * @code: The FCP status code to set
1691 */
1692static void fc_fcp_recovery(struct fc_fcp_pkt *fsp, u8 code)
1693{
1694 FC_FCP_DBG(fsp, "start recovery code %x\n", code);
1695 fsp->status_code = code;
1696 fsp->cdb_status = 0;
1697 fsp->io_status = 0;
1698 if (!fsp->cmd)
1699 /*
1700 * Only abort non-scsi commands; otherwise let the
1701 * scsi command timer fire and scsi-ml escalate.
1702 */
1703 fc_fcp_send_abort(fsp);
1704}
1705
1706/**
1707 * fc_fcp_srr() - Send a SRR request (Sequence Retransmission Request)
1708 * @fsp: The FCP packet the SRR is to be sent on
1709 * @r_ctl: The R_CTL field for the SRR request
1710 * @offset: The SRR relative offset
1711 * This is called after receiving status but insufficient data, or
1712 * when expecting status but the request has timed out.
1713 */
1714static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1715{
1716 struct fc_lport *lport = fsp->lp;
1717 struct fc_rport *rport;
1718 struct fc_rport_libfc_priv *rpriv;
1719 struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1720 struct fc_seq *seq;
1721 struct fcp_srr *srr;
1722 struct fc_frame *fp;
1723
1724 rport = fsp->rport;
1725 rpriv = rport->dd_data;
1726
1727 if (!(rpriv->flags & FC_RP_FLAGS_RETRY) ||
1728 rpriv->rp_state != RPORT_ST_READY)
1729 goto retry; /* shouldn't happen */
1730 fp = fc_fcp_frame_alloc(lport, len: sizeof(*srr));
1731 if (!fp)
1732 goto retry;
1733
1734 srr = fc_frame_payload_get(fp, len: sizeof(*srr));
1735 memset(srr, 0, sizeof(*srr));
1736 srr->srr_op = ELS_SRR;
1737 srr->srr_ox_id = htons(ep->oxid);
1738 srr->srr_rx_id = htons(ep->rxid);
1739 srr->srr_r_ctl = r_ctl;
1740 srr->srr_rel_off = htonl(offset);
1741
1742 fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_ELS4_REQ, did: rport->port_id,
1743 sid: rpriv->local_port->port_id, type: FC_TYPE_FCP,
1744 FC_FCTL_REQ, parm_offset: 0);
1745
1746 seq = fc_exch_seq_send(lport, fp, resp: fc_fcp_srr_resp,
1747 destructor: fc_fcp_pkt_destroy,
1748 arg: fsp, timer_msec: get_fsp_rec_tov(fsp));
1749 if (!seq)
1750 goto retry;
1751
1752 fsp->recov_seq = seq;
1753 fsp->xfer_len = offset;
1754 fsp->xfer_contig_end = offset;
1755 fsp->state &= ~FC_SRB_RCV_STATUS;
1756 fc_fcp_pkt_hold(fsp); /* hold for outstanding SRR */
1757 return;
1758retry:
1759 fc_fcp_retry_cmd(fsp, FC_TRANS_RESET);
1760}
1761
1762/**
1763 * fc_fcp_srr_resp() - Handler for SRR response
1764 * @seq: The sequence the SRR is on
1765 * @fp: The SRR frame
1766 * @arg: The FCP packet the SRR is on
1767 */
1768static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1769{
1770 struct fc_fcp_pkt *fsp = arg;
1771 struct fc_frame_header *fh;
1772
1773 if (IS_ERR(ptr: fp)) {
1774 fc_fcp_srr_error(fsp, fp);
1775 return;
1776 }
1777
1778 if (fc_fcp_lock_pkt(fsp))
1779 goto out;
1780
1781 fh = fc_frame_header_get(fp);
1782 /*
1783 * BUG? fc_fcp_srr_error calls fc_exch_done which would release
1784 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1785 * then fc_exch_timeout would be sending an abort. The fc_exch_done
1786 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1787 * an abort response though.
1788 */
1789 if (fh->fh_type == FC_TYPE_BLS) {
1790 fc_fcp_unlock_pkt(fsp);
1791 return;
1792 }
1793
1794 switch (fc_frame_payload_op(fp)) {
1795 case ELS_LS_ACC:
1796 fsp->recov_retry = 0;
1797 fc_fcp_timer_set(fsp, delay: get_fsp_rec_tov(fsp));
1798 break;
1799 case ELS_LS_RJT:
1800 default:
1801 fc_fcp_recovery(fsp, FC_ERROR);
1802 break;
1803 }
1804 fc_fcp_unlock_pkt(fsp);
1805out:
1806 fc_exch_done(sp: seq);
1807 fc_frame_free(fp);
1808}
1809
1810/**
1811 * fc_fcp_srr_error() - Handler for SRR errors
1812 * @fsp: The FCP packet that the SRR error is on
1813 * @fp: The SRR frame
1814 */
1815static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1816{
1817 if (fc_fcp_lock_pkt(fsp))
1818 goto out;
1819 switch (PTR_ERR(ptr: fp)) {
1820 case -FC_EX_TIMEOUT:
1821 FC_FCP_DBG(fsp, "SRR timeout, retries %d\n", fsp->recov_retry);
1822 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1823 fc_fcp_rec(fsp);
1824 else
1825 fc_fcp_recovery(fsp, FC_TIMED_OUT);
1826 break;
1827 case -FC_EX_CLOSED: /* e.g., link failure */
1828 FC_FCP_DBG(fsp, "SRR error, exchange closed\n");
1829 fallthrough;
1830 default:
1831 fc_fcp_retry_cmd(fsp, FC_ERROR);
1832 break;
1833 }
1834 fc_fcp_unlock_pkt(fsp);
1835out:
1836 fc_exch_done(sp: fsp->recov_seq);
1837}
1838
1839/**
1840 * fc_fcp_lport_queue_ready() - Determine if the lport and it's queue is ready
1841 * @lport: The local port to be checked
1842 */
1843static inline int fc_fcp_lport_queue_ready(struct fc_lport *lport)
1844{
1845 /* lock ? */
1846 return (lport->state == LPORT_ST_READY) &&
1847 lport->link_up && !lport->qfull;
1848}
1849
1850/**
1851 * fc_queuecommand() - The queuecommand function of the SCSI template
1852 * @shost: The Scsi_Host that the command was issued to
1853 * @sc_cmd: The scsi_cmnd to be executed
1854 *
1855 * This is the i/o strategy routine, called by the SCSI layer.
1856 */
1857int fc_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *sc_cmd)
1858{
1859 struct fc_lport *lport = shost_priv(shost);
1860 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1861 struct fc_fcp_pkt *fsp;
1862 int rval;
1863 int rc = 0;
1864
1865 rval = fc_remote_port_chkready(rport);
1866 if (rval) {
1867 sc_cmd->result = rval;
1868 scsi_done(cmd: sc_cmd);
1869 return 0;
1870 }
1871
1872 if (!*(struct fc_remote_port **)rport->dd_data) {
1873 /*
1874 * rport is transitioning from blocked/deleted to
1875 * online
1876 */
1877 sc_cmd->result = DID_IMM_RETRY << 16;
1878 scsi_done(cmd: sc_cmd);
1879 goto out;
1880 }
1881
1882 if (!fc_fcp_lport_queue_ready(lport)) {
1883 if (lport->qfull) {
1884 if (fc_fcp_can_queue_ramp_down(lport))
1885 shost_printk(KERN_ERR, lport->host,
1886 "libfc: queue full, "
1887 "reducing can_queue to %d.\n",
1888 lport->host->can_queue);
1889 }
1890 rc = SCSI_MLQUEUE_HOST_BUSY;
1891 goto out;
1892 }
1893
1894 fsp = fc_fcp_pkt_alloc(lport, GFP_ATOMIC);
1895 if (fsp == NULL) {
1896 rc = SCSI_MLQUEUE_HOST_BUSY;
1897 goto out;
1898 }
1899
1900 /*
1901 * build the libfc request pkt
1902 */
1903 fsp->cmd = sc_cmd; /* save the cmd */
1904 fsp->rport = rport; /* set the remote port ptr */
1905
1906 /*
1907 * set up the transfer length
1908 */
1909 fsp->data_len = scsi_bufflen(cmd: sc_cmd);
1910 fsp->xfer_len = 0;
1911
1912 /*
1913 * setup the data direction
1914 */
1915 if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1916 fsp->req_flags = FC_SRB_READ;
1917 this_cpu_inc(lport->stats->InputRequests);
1918 this_cpu_add(lport->stats->InputBytes, fsp->data_len);
1919 } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1920 fsp->req_flags = FC_SRB_WRITE;
1921 this_cpu_inc(lport->stats->OutputRequests);
1922 this_cpu_add(lport->stats->OutputBytes, fsp->data_len);
1923 } else {
1924 fsp->req_flags = 0;
1925 this_cpu_inc(lport->stats->ControlRequests);
1926 }
1927
1928 /*
1929 * send it to the lower layer
1930 * if we get -1 return then put the request in the pending
1931 * queue.
1932 */
1933 rval = fc_fcp_pkt_send(lport, fsp);
1934 if (rval != 0) {
1935 fsp->state = FC_SRB_FREE;
1936 fc_fcp_pkt_release(fsp);
1937 rc = SCSI_MLQUEUE_HOST_BUSY;
1938 }
1939out:
1940 return rc;
1941}
1942EXPORT_SYMBOL(fc_queuecommand);
1943
1944/**
1945 * fc_io_compl() - Handle responses for completed commands
1946 * @fsp: The FCP packet that is complete
1947 *
1948 * Translates fcp_pkt errors to a Linux SCSI errors.
1949 * The fcp packet lock must be held when calling.
1950 */
1951static void fc_io_compl(struct fc_fcp_pkt *fsp)
1952{
1953 struct fc_fcp_internal *si;
1954 struct scsi_cmnd *sc_cmd;
1955 struct fc_lport *lport;
1956 unsigned long flags;
1957
1958 /* release outstanding ddp context */
1959 fc_fcp_ddp_done(fsp);
1960
1961 fsp->state |= FC_SRB_COMPL;
1962 if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1963 spin_unlock_bh(lock: &fsp->scsi_pkt_lock);
1964 del_timer_sync(timer: &fsp->timer);
1965 spin_lock_bh(lock: &fsp->scsi_pkt_lock);
1966 }
1967
1968 lport = fsp->lp;
1969 si = fc_get_scsi_internal(lport);
1970
1971 /*
1972 * if can_queue ramp down is done then try can_queue ramp up
1973 * since commands are completing now.
1974 */
1975 if (si->last_can_queue_ramp_down_time)
1976 fc_fcp_can_queue_ramp_up(lport);
1977
1978 sc_cmd = fsp->cmd;
1979 libfc_priv(cmd: sc_cmd)->status = fsp->cdb_status;
1980 switch (fsp->status_code) {
1981 case FC_COMPLETE:
1982 if (fsp->cdb_status == 0) {
1983 /*
1984 * good I/O status
1985 */
1986 sc_cmd->result = DID_OK << 16;
1987 if (fsp->scsi_resid)
1988 libfc_priv(cmd: sc_cmd)->resid_len = fsp->scsi_resid;
1989 } else {
1990 /*
1991 * transport level I/O was ok but scsi
1992 * has non zero status
1993 */
1994 sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1995 }
1996 break;
1997 case FC_ERROR:
1998 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
1999 "due to FC_ERROR\n");
2000 sc_cmd->result = DID_ERROR << 16;
2001 break;
2002 case FC_DATA_UNDRUN:
2003 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
2004 /*
2005 * scsi status is good but transport level
2006 * underrun.
2007 */
2008 if (fsp->state & FC_SRB_RCV_STATUS) {
2009 sc_cmd->result = DID_OK << 16;
2010 } else {
2011 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml"
2012 " due to FC_DATA_UNDRUN (trans)\n");
2013 sc_cmd->result = DID_ERROR << 16;
2014 }
2015 } else {
2016 /*
2017 * scsi got underrun, this is an error
2018 */
2019 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
2020 "due to FC_DATA_UNDRUN (scsi)\n");
2021 libfc_priv(cmd: sc_cmd)->resid_len = fsp->scsi_resid;
2022 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
2023 }
2024 break;
2025 case FC_DATA_OVRRUN:
2026 /*
2027 * overrun is an error
2028 */
2029 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
2030 "due to FC_DATA_OVRRUN\n");
2031 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
2032 break;
2033 case FC_CMD_ABORTED:
2034 if (host_byte(sc_cmd->result) == DID_TIME_OUT)
2035 FC_FCP_DBG(fsp, "Returning DID_TIME_OUT to scsi-ml "
2036 "due to FC_CMD_ABORTED\n");
2037 else {
2038 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
2039 "due to FC_CMD_ABORTED\n");
2040 set_host_byte(cmd: sc_cmd, status: DID_ERROR);
2041 }
2042 sc_cmd->result |= fsp->io_status;
2043 break;
2044 case FC_CMD_RESET:
2045 FC_FCP_DBG(fsp, "Returning DID_RESET to scsi-ml "
2046 "due to FC_CMD_RESET\n");
2047 sc_cmd->result = (DID_RESET << 16);
2048 break;
2049 case FC_TRANS_RESET:
2050 FC_FCP_DBG(fsp, "Returning DID_SOFT_ERROR to scsi-ml "
2051 "due to FC_TRANS_RESET\n");
2052 sc_cmd->result = (DID_SOFT_ERROR << 16);
2053 break;
2054 case FC_HRD_ERROR:
2055 FC_FCP_DBG(fsp, "Returning DID_NO_CONNECT to scsi-ml "
2056 "due to FC_HRD_ERROR\n");
2057 sc_cmd->result = (DID_NO_CONNECT << 16);
2058 break;
2059 case FC_CRC_ERROR:
2060 FC_FCP_DBG(fsp, "Returning DID_PARITY to scsi-ml "
2061 "due to FC_CRC_ERROR\n");
2062 sc_cmd->result = (DID_PARITY << 16);
2063 break;
2064 case FC_TIMED_OUT:
2065 FC_FCP_DBG(fsp, "Returning DID_TIME_OUT to scsi-ml "
2066 "due to FC_TIMED_OUT\n");
2067 sc_cmd->result = (DID_TIME_OUT << 16);
2068 break;
2069 default:
2070 FC_FCP_DBG(fsp, "Returning DID_ERROR to scsi-ml "
2071 "due to unknown error\n");
2072 sc_cmd->result = (DID_ERROR << 16);
2073 break;
2074 }
2075
2076 if (lport->state != LPORT_ST_READY && fsp->status_code != FC_COMPLETE)
2077 sc_cmd->result = (DID_TRANSPORT_DISRUPTED << 16);
2078
2079 spin_lock_irqsave(&si->scsi_queue_lock, flags);
2080 list_del(entry: &fsp->list);
2081 libfc_priv(cmd: sc_cmd)->fsp = NULL;
2082 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
2083 scsi_done(cmd: sc_cmd);
2084
2085 /* release ref from initial allocation in queue command */
2086 fc_fcp_pkt_release(fsp);
2087}
2088
2089/**
2090 * fc_eh_abort() - Abort a command
2091 * @sc_cmd: The SCSI command to abort
2092 *
2093 * From SCSI host template.
2094 * Send an ABTS to the target device and wait for the response.
2095 */
2096int fc_eh_abort(struct scsi_cmnd *sc_cmd)
2097{
2098 struct fc_fcp_pkt *fsp;
2099 struct fc_lport *lport;
2100 struct fc_fcp_internal *si;
2101 int rc = FAILED;
2102 unsigned long flags;
2103 int rval;
2104
2105 rval = fc_block_scsi_eh(cmnd: sc_cmd);
2106 if (rval)
2107 return rval;
2108
2109 lport = shost_priv(shost: sc_cmd->device->host);
2110 if (lport->state != LPORT_ST_READY)
2111 return rc;
2112 else if (!lport->link_up)
2113 return rc;
2114
2115 si = fc_get_scsi_internal(lport);
2116 spin_lock_irqsave(&si->scsi_queue_lock, flags);
2117 fsp = libfc_priv(cmd: sc_cmd)->fsp;
2118 if (!fsp) {
2119 /* command completed while scsi eh was setting up */
2120 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
2121 return SUCCESS;
2122 }
2123 /* grab a ref so the fsp and sc_cmd cannot be released from under us */
2124 fc_fcp_pkt_hold(fsp);
2125 spin_unlock_irqrestore(lock: &si->scsi_queue_lock, flags);
2126
2127 if (fc_fcp_lock_pkt(fsp)) {
2128 /* completed while we were waiting for timer to be deleted */
2129 rc = SUCCESS;
2130 goto release_pkt;
2131 }
2132
2133 rc = fc_fcp_pkt_abort(fsp);
2134 fc_fcp_unlock_pkt(fsp);
2135
2136release_pkt:
2137 fc_fcp_pkt_release(fsp);
2138 return rc;
2139}
2140EXPORT_SYMBOL(fc_eh_abort);
2141
2142/**
2143 * fc_eh_device_reset() - Reset a single LUN
2144 * @sc_cmd: The SCSI command which identifies the device whose
2145 * LUN is to be reset
2146 *
2147 * Set from SCSI host template.
2148 */
2149int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
2150{
2151 struct fc_lport *lport;
2152 struct fc_fcp_pkt *fsp;
2153 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
2154 int rc = FAILED;
2155 int rval;
2156
2157 rval = fc_block_scsi_eh(cmnd: sc_cmd);
2158 if (rval)
2159 return rval;
2160
2161 lport = shost_priv(shost: sc_cmd->device->host);
2162
2163 if (lport->state != LPORT_ST_READY)
2164 return rc;
2165
2166 FC_SCSI_DBG(lport, "Resetting rport (%6.6x)\n", rport->port_id);
2167
2168 fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO);
2169 if (fsp == NULL) {
2170 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
2171 goto out;
2172 }
2173
2174 /*
2175 * Build the libfc request pkt. Do not set the scsi cmnd, because
2176 * the sc passed in is not setup for execution like when sent
2177 * through the queuecommand callout.
2178 */
2179 fsp->rport = rport; /* set the remote port ptr */
2180
2181 /*
2182 * flush outstanding commands
2183 */
2184 rc = fc_lun_reset(lport, fsp, scmd_id(sc_cmd), lun: sc_cmd->device->lun);
2185 fsp->state = FC_SRB_FREE;
2186 fc_fcp_pkt_release(fsp);
2187
2188out:
2189 return rc;
2190}
2191EXPORT_SYMBOL(fc_eh_device_reset);
2192
2193/**
2194 * fc_eh_host_reset() - Reset a Scsi_Host.
2195 * @sc_cmd: The SCSI command that identifies the SCSI host to be reset
2196 */
2197int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2198{
2199 struct Scsi_Host *shost = sc_cmd->device->host;
2200 struct fc_lport *lport = shost_priv(shost);
2201 unsigned long wait_tmo;
2202
2203 FC_SCSI_DBG(lport, "Resetting host\n");
2204
2205 fc_lport_reset(lport);
2206 wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2207 while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies,
2208 wait_tmo))
2209 msleep(msecs: 1000);
2210
2211 if (fc_fcp_lport_queue_ready(lport)) {
2212 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2213 "on port (%6.6x)\n", lport->port_id);
2214 return SUCCESS;
2215 } else {
2216 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2217 "port (%6.6x) is not ready.\n",
2218 lport->port_id);
2219 return FAILED;
2220 }
2221}
2222EXPORT_SYMBOL(fc_eh_host_reset);
2223
2224/**
2225 * fc_slave_alloc() - Configure the queue depth of a Scsi_Host
2226 * @sdev: The SCSI device that identifies the SCSI host
2227 *
2228 * Configures queue depth based on host's cmd_per_len. If not set
2229 * then we use the libfc default.
2230 */
2231int fc_slave_alloc(struct scsi_device *sdev)
2232{
2233 struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2234
2235 if (!rport || fc_remote_port_chkready(rport))
2236 return -ENXIO;
2237
2238 scsi_change_queue_depth(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2239 return 0;
2240}
2241EXPORT_SYMBOL(fc_slave_alloc);
2242
2243/**
2244 * fc_fcp_destroy() - Tear down the FCP layer for a given local port
2245 * @lport: The local port that no longer needs the FCP layer
2246 */
2247void fc_fcp_destroy(struct fc_lport *lport)
2248{
2249 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
2250
2251 if (!list_empty(head: &si->scsi_pkt_queue))
2252 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2253 "port (%6.6x)\n", lport->port_id);
2254
2255 mempool_destroy(pool: si->scsi_pkt_pool);
2256 kfree(objp: si);
2257 lport->scsi_priv = NULL;
2258}
2259EXPORT_SYMBOL(fc_fcp_destroy);
2260
2261int fc_setup_fcp(void)
2262{
2263 int rc = 0;
2264
2265 scsi_pkt_cachep = kmem_cache_create(name: "libfc_fcp_pkt",
2266 size: sizeof(struct fc_fcp_pkt),
2267 align: 0, SLAB_HWCACHE_ALIGN, NULL);
2268 if (!scsi_pkt_cachep) {
2269 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2270 "module load failed!");
2271 rc = -ENOMEM;
2272 }
2273
2274 return rc;
2275}
2276
2277void fc_destroy_fcp(void)
2278{
2279 kmem_cache_destroy(s: scsi_pkt_cachep);
2280}
2281
2282/**
2283 * fc_fcp_init() - Initialize the FCP layer for a local port
2284 * @lport: The local port to initialize the exchange layer for
2285 */
2286int fc_fcp_init(struct fc_lport *lport)
2287{
2288 int rc;
2289 struct fc_fcp_internal *si;
2290
2291 if (!lport->tt.fcp_cmd_send)
2292 lport->tt.fcp_cmd_send = fc_fcp_cmd_send;
2293
2294 if (!lport->tt.fcp_cleanup)
2295 lport->tt.fcp_cleanup = fc_fcp_cleanup;
2296
2297 if (!lport->tt.fcp_abort_io)
2298 lport->tt.fcp_abort_io = fc_fcp_abort_io;
2299
2300 si = kzalloc(size: sizeof(struct fc_fcp_internal), GFP_KERNEL);
2301 if (!si)
2302 return -ENOMEM;
2303 lport->scsi_priv = si;
2304 si->max_can_queue = lport->host->can_queue;
2305 INIT_LIST_HEAD(list: &si->scsi_pkt_queue);
2306 spin_lock_init(&si->scsi_queue_lock);
2307
2308 si->scsi_pkt_pool = mempool_create_slab_pool(min_nr: 2, kc: scsi_pkt_cachep);
2309 if (!si->scsi_pkt_pool) {
2310 rc = -ENOMEM;
2311 goto free_internal;
2312 }
2313 return 0;
2314
2315free_internal:
2316 kfree(objp: si);
2317 return rc;
2318}
2319EXPORT_SYMBOL(fc_fcp_init);
2320

source code of linux/drivers/scsi/libfc/fc_fcp.c