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
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.
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
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.
19 * Maintained at www.Open-FCoE.org
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>
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>
37 #include <scsi/fc/fc_fc2.h>
39 #include <scsi/libfc.h>
40 #include <scsi/fc_encode.h>
44 struct kmem_cache *scsi_pkt_cachep;
46 /* SRB state definitions */
47 #define FC_SRB_FREE 0 /* cmd is free */
48 #define FC_SRB_CMD_SENT (1 << 0) /* cmd has been sent */
49 #define FC_SRB_RCV_STATUS (1 << 1) /* response has arrived */
50 #define FC_SRB_ABORT_PENDING (1 << 2) /* cmd abort sent to device */
51 #define FC_SRB_ABORTED (1 << 3) /* abort acknowledged */
52 #define FC_SRB_DISCONTIG (1 << 4) /* non-sequential data recvd */
53 #define FC_SRB_COMPL (1 << 5) /* fc_io_compl has been run */
54 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6) /* timer function processing */
56 #define FC_SRB_READ (1 << 1)
57 #define FC_SRB_WRITE (1 << 0)
60 * The SCp.ptr should be tested and set under the host lock. NULL indicates
61 * that the command has been retruned to the scsi layer.
63 #define CMD_SP(Cmnd) ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
64 #define CMD_ENTRY_STATUS(Cmnd) ((Cmnd)->SCp.have_data_in)
65 #define CMD_COMPL_STATUS(Cmnd) ((Cmnd)->SCp.this_residual)
66 #define CMD_SCSI_STATUS(Cmnd) ((Cmnd)->SCp.Status)
67 #define CMD_RESID_LEN(Cmnd) ((Cmnd)->SCp.buffers_residual)
70 * struct fc_fcp_internal - FCP layer internal data
71 * @scsi_pkt_pool: Memory pool to draw FCP packets from
72 * @scsi_queue_lock: Protects the scsi_pkt_queue
73 * @scsi_pkt_queue: Current FCP packets
74 * @last_can_queue_ramp_down_time: ramp down time
75 * @last_can_queue_ramp_up_time: ramp up time
76 * @max_can_queue: max can_queue size
78 struct fc_fcp_internal {
79 mempool_t *scsi_pkt_pool;
80 spinlock_t scsi_queue_lock;
81 struct list_head scsi_pkt_queue;
82 unsigned long last_can_queue_ramp_down_time;
83 unsigned long last_can_queue_ramp_up_time;
87 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
91 * FC scsi I/O related functions
93 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
94 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
95 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
96 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
97 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
98 static void fc_fcp_error(struct fc_fcp_pkt *, struct fc_frame *);
99 static void fc_timeout_error(struct fc_fcp_pkt *);
100 static void fc_fcp_timeout(unsigned long);
101 static void fc_fcp_rec(struct fc_fcp_pkt *);
102 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
103 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
104 static void fc_io_compl(struct fc_fcp_pkt *);
106 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
107 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
108 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
111 * command status codes
113 #define FC_COMPLETE 0
114 #define FC_CMD_ABORTED 1
115 #define FC_CMD_RESET 2
116 #define FC_CMD_PLOGO 3
118 #define FC_TRANS_ERR 5
119 #define FC_DATA_OVRRUN 6
120 #define FC_DATA_UNDRUN 7
122 #define FC_HRD_ERROR 9
123 #define FC_CMD_TIME_OUT 10
126 * Error recovery timeout values.
128 #define FC_SCSI_ER_TIMEOUT (10 * HZ)
129 #define FC_SCSI_TM_TOV (10 * HZ)
130 #define FC_SCSI_REC_TOV (2 * HZ)
131 #define FC_HOST_RESET_TIMEOUT (30 * HZ)
132 #define FC_CAN_QUEUE_PERIOD (60 * HZ)
134 #define FC_MAX_ERROR_CNT 5
135 #define FC_MAX_RECOV_RETRY 3
137 #define FC_FCP_DFLT_QUEUE_DEPTH 32
140 * fc_fcp_pkt_alloc() - Allocate a fcp_pkt
141 * @lport: The local port that the FCP packet is for
142 * @gfp: GFP flags for allocation
144 * Return value: fcp_pkt structure or null on allocation failure.
145 * Context: Can be called from process context, no lock is required.
147 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp)
149 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
150 struct fc_fcp_pkt *fsp;
152 fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
154 memset(fsp, 0, sizeof(*fsp));
156 atomic_set(&fsp->ref_cnt, 1);
157 init_timer(&fsp->timer);
158 INIT_LIST_HEAD(&fsp->list);
159 spin_lock_init(&fsp->scsi_pkt_lock);
165 * fc_fcp_pkt_release() - Release hold on a fcp_pkt
166 * @fsp: The FCP packet to be released
168 * Context: Can be called from process or interrupt context,
169 * no lock is required.
171 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
173 if (atomic_dec_and_test(&fsp->ref_cnt)) {
174 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
176 mempool_free(fsp, si->scsi_pkt_pool);
181 * fc_fcp_pkt_hold() - Hold a fcp_pkt
182 * @fsp: The FCP packet to be held
184 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
186 atomic_inc(&fsp->ref_cnt);
190 * fc_fcp_pkt_destory() - Release hold on a fcp_pkt
191 * @seq: The sequence that the FCP packet is on (required by destructor API)
192 * @fsp: The FCP packet to be released
194 * This routine is called by a destructor callback in the exch_seq_send()
195 * routine of the libfc Transport Template. The 'struct fc_seq' is a required
196 * argument even though it is not used by this routine.
198 * Context: No locking required.
200 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
202 fc_fcp_pkt_release(fsp);
206 * fc_fcp_lock_pkt() - Lock a fcp_pkt and increase its reference count
207 * @fsp: The FCP packet to be locked and incremented
209 * We should only return error if we return a command to SCSI-ml before
210 * getting a response. This can happen in cases where we send a abort, but
211 * do not wait for the response and the abort and command can be passing
212 * each other on the wire/network-layer.
214 * Note: this function locks the packet and gets a reference to allow
215 * callers to call the completion function while the lock is held and
216 * not have to worry about the packets refcount.
218 * TODO: Maybe we should just have callers grab/release the lock and
219 * have a function that they call to verify the fsp and grab a ref if
222 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
224 spin_lock_bh(&fsp->scsi_pkt_lock);
225 if (fsp->state & FC_SRB_COMPL) {
226 spin_unlock_bh(&fsp->scsi_pkt_lock);
230 fc_fcp_pkt_hold(fsp);
235 * fc_fcp_unlock_pkt() - Release a fcp_pkt's lock and decrement its
237 * @fsp: The FCP packet to be unlocked and decremented
239 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
241 spin_unlock_bh(&fsp->scsi_pkt_lock);
242 fc_fcp_pkt_release(fsp);
246 * fc_fcp_timer_set() - Start a timer for a fcp_pkt
247 * @fsp: The FCP packet to start a timer for
248 * @delay: The timeout period for the timer
250 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
252 if (!(fsp->state & FC_SRB_COMPL))
253 mod_timer(&fsp->timer, jiffies + delay);
257 * fc_fcp_send_abort() - Send an abort for exchanges associated with a
259 * @fsp: The FCP packet to abort exchanges on
261 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
266 fsp->state |= FC_SRB_ABORT_PENDING;
267 return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
271 * fc_fcp_retry_cmd() - Retry a fcp_pkt
272 * @fsp: The FCP packet to be retried
274 * Sets the status code to be FC_ERROR and then calls
275 * fc_fcp_complete_locked() which in turn calls fc_io_compl().
276 * fc_io_compl() will notify the SCSI-ml that the I/O is done.
277 * The SCSI-ml will retry the command.
279 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
282 fsp->lp->tt.exch_done(fsp->seq_ptr);
286 fsp->state &= ~FC_SRB_ABORT_PENDING;
288 fsp->status_code = FC_ERROR;
289 fc_fcp_complete_locked(fsp);
293 * fc_fcp_ddp_setup() - Calls a LLD's ddp_setup routine to set up DDP context
294 * @fsp: The FCP packet that will manage the DDP frames
295 * @xid: The XID that will be used for the DDP exchange
297 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
299 struct fc_lport *lport;
302 if ((fsp->req_flags & FC_SRB_READ) &&
303 (lport->lro_enabled) && (lport->tt.ddp_setup)) {
304 if (lport->tt.ddp_setup(lport, xid, scsi_sglist(fsp->cmd),
305 scsi_sg_count(fsp->cmd)))
311 * fc_fcp_ddp_done() - Calls a LLD's ddp_done routine to release any
312 * DDP related resources for a fcp_pkt
313 * @fsp: The FCP packet that DDP had been used on
315 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
317 struct fc_lport *lport;
322 if (fsp->xfer_ddp == FC_XID_UNKNOWN)
326 if (lport->tt.ddp_done) {
327 fsp->xfer_len = lport->tt.ddp_done(lport, fsp->xfer_ddp);
328 fsp->xfer_ddp = FC_XID_UNKNOWN;
333 * fc_fcp_can_queue_ramp_up() - increases can_queue
334 * @lport: lport to ramp up can_queue
336 * Locking notes: Called with Scsi_Host lock held
338 static void fc_fcp_can_queue_ramp_up(struct fc_lport *lport)
340 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
343 if (si->last_can_queue_ramp_up_time &&
344 (time_before(jiffies, si->last_can_queue_ramp_up_time +
345 FC_CAN_QUEUE_PERIOD)))
348 if (time_before(jiffies, si->last_can_queue_ramp_down_time +
349 FC_CAN_QUEUE_PERIOD))
352 si->last_can_queue_ramp_up_time = jiffies;
354 can_queue = lport->host->can_queue << 1;
355 if (can_queue >= si->max_can_queue) {
356 can_queue = si->max_can_queue;
357 si->last_can_queue_ramp_down_time = 0;
359 lport->host->can_queue = can_queue;
360 shost_printk(KERN_ERR, lport->host, "libfc: increased "
361 "can_queue to %d.\n", can_queue);
365 * fc_fcp_can_queue_ramp_down() - reduces can_queue
366 * @lport: lport to reduce can_queue
368 * If we are getting memory allocation failures, then we may
369 * be trying to execute too many commands. We let the running
370 * commands complete or timeout, then try again with a reduced
371 * can_queue. Eventually we will hit the point where we run
372 * on all reserved structs.
374 * Locking notes: Called with Scsi_Host lock held
376 static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport)
378 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
381 if (si->last_can_queue_ramp_down_time &&
382 (time_before(jiffies, si->last_can_queue_ramp_down_time +
383 FC_CAN_QUEUE_PERIOD)))
386 si->last_can_queue_ramp_down_time = jiffies;
388 can_queue = lport->host->can_queue;
392 lport->host->can_queue = can_queue;
393 shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n"
394 "Reducing can_queue to %d.\n", can_queue);
398 * fc_fcp_frame_alloc() - Allocates fc_frame structure and buffer.
399 * @lport: fc lport struct
400 * @len: payload length
402 * Allocates fc_frame structure and buffer but if fails to allocate
403 * then reduce can_queue.
405 static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport,
411 fp = fc_frame_alloc(lport, len);
416 spin_lock_irqsave(lport->host->host_lock, flags);
417 fc_fcp_can_queue_ramp_down(lport);
418 spin_unlock_irqrestore(lport->host->host_lock, flags);
423 * fc_fcp_recv_data() - Handler for receiving SCSI-FCP data from a target
424 * @fsp: The FCP packet the data is on
425 * @fp: The data frame
427 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
429 struct scsi_cmnd *sc = fsp->cmd;
430 struct fc_lport *lport = fsp->lp;
431 struct fcoe_dev_stats *stats;
432 struct fc_frame_header *fh;
439 struct scatterlist *sg;
442 fh = fc_frame_header_get(fp);
443 offset = ntohl(fh->fh_parm_offset);
444 start_offset = offset;
445 len = fr_len(fp) - sizeof(*fh);
446 buf = fc_frame_payload_get(fp, 0);
448 /* if this I/O is ddped, update xfer len */
449 fc_fcp_ddp_done(fsp);
451 if (offset + len > fsp->data_len) {
452 /* this should never happen */
453 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
454 fc_frame_crc_check(fp))
456 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
457 "data_len %x\n", len, offset, fsp->data_len);
458 fc_fcp_retry_cmd(fsp);
461 if (offset != fsp->xfer_len)
462 fsp->state |= FC_SRB_DISCONTIG;
464 sg = scsi_sglist(sc);
465 nents = scsi_sg_count(sc);
467 if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) {
468 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
469 &offset, KM_SOFTIRQ0, NULL);
471 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
472 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
473 &offset, KM_SOFTIRQ0, &crc);
474 buf = fc_frame_payload_get(fp, 0);
476 crc = crc32(crc, buf + len, 4 - (len % 4));
478 if (~crc != le32_to_cpu(fr_crc(fp))) {
480 stats = fc_lport_get_stats(lport);
481 stats->ErrorFrames++;
482 /* FIXME - per cpu count, not total count! */
483 if (stats->InvalidCRCCount++ < 5)
484 printk(KERN_WARNING "libfc: CRC error on data "
485 "frame for port (%6x)\n",
486 fc_host_port_id(lport->host));
488 * Assume the frame is total garbage.
489 * We may have copied it over the good part
491 * If so, we need to retry the entire operation.
492 * Otherwise, ignore it.
494 if (fsp->state & FC_SRB_DISCONTIG)
495 fc_fcp_retry_cmd(fsp);
500 if (fsp->xfer_contig_end == start_offset)
501 fsp->xfer_contig_end += copy_len;
502 fsp->xfer_len += copy_len;
505 * In the very rare event that this data arrived after the response
506 * and completes the transfer, call the completion handler.
508 if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
509 fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
510 fc_fcp_complete_locked(fsp);
514 * fc_fcp_send_data() - Send SCSI data to a target
515 * @fsp: The FCP packet the data is on
516 * @sp: The sequence the data is to be sent on
517 * @offset: The starting offset for this data request
518 * @seq_blen: The burst length for this data request
520 * Called after receiving a Transfer Ready data descriptor.
521 * If the LLD is capable of sequence offload then send down the
522 * seq_blen amount of data in single frame, otherwise send
523 * multiple frames of the maximum frame payload supported by
526 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
527 size_t offset, size_t seq_blen)
530 struct scsi_cmnd *sc;
531 struct scatterlist *sg;
532 struct fc_frame *fp = NULL;
533 struct fc_lport *lport = fsp->lp;
539 size_t frame_offset, fh_parm_offset;
544 int using_sg = lport->sg_supp;
547 WARN_ON(seq_blen <= 0);
548 if (unlikely(offset + seq_blen > fsp->data_len)) {
549 /* this should never happen */
550 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
551 "offset %zx\n", seq_blen, offset);
552 fc_fcp_send_abort(fsp);
554 } else if (offset != fsp->xfer_len) {
555 /* Out of Order Data Request - no problem, but unexpected. */
556 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
557 "seq_blen %zx offset %zx\n", seq_blen, offset);
561 * if LLD is capable of seq_offload then set transport
562 * burst length (t_blen) to seq_blen, otherwise set t_blen
563 * to max FC frame payload previously set in fsp->max_payload.
565 t_blen = fsp->max_payload;
566 if (lport->seq_offload) {
567 t_blen = min(seq_blen, (size_t)lport->lso_max);
568 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
569 fsp, seq_blen, lport->lso_max, t_blen);
572 WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
574 t_blen &= ~(512 - 1); /* round down to block size */
575 WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD); /* won't go below 256 */
578 remaining = seq_blen;
579 fh_parm_offset = frame_offset = offset;
581 seq = lport->tt.seq_start_next(seq);
582 f_ctl = FC_FC_REL_OFF;
585 sg = scsi_sglist(sc);
587 while (remaining > 0 && sg) {
588 if (offset >= sg->length) {
589 offset -= sg->length;
594 tlen = min(t_blen, remaining);
597 * TODO. Temporary workaround. fc_seq_send() can't
598 * handle odd lengths in non-linear skbs.
599 * This will be the final fragment only.
603 fp = fc_frame_alloc(lport, using_sg ? 0 : tlen);
607 data = fc_frame_header_get(fp) + 1;
608 fh_parm_offset = frame_offset;
609 fr_max_payload(fp) = fsp->max_payload;
612 off = offset + sg->offset;
613 sg_bytes = min(tlen, sg->length - offset);
614 sg_bytes = min(sg_bytes,
615 (size_t) (PAGE_SIZE - (off & ~PAGE_MASK)));
616 page = sg_page(sg) + (off >> PAGE_SHIFT);
619 skb_fill_page_desc(fp_skb(fp),
620 skb_shinfo(fp_skb(fp))->nr_frags,
621 page, off & ~PAGE_MASK, sg_bytes);
622 fp_skb(fp)->data_len += sg_bytes;
623 fr_len(fp) += sg_bytes;
624 fp_skb(fp)->truesize += PAGE_SIZE;
627 * The scatterlist item may be bigger than PAGE_SIZE,
628 * but we must not cross pages inside the kmap.
630 page_addr = kmap_atomic(page, KM_SOFTIRQ0);
631 memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
633 kunmap_atomic(page_addr, KM_SOFTIRQ0);
637 frame_offset += sg_bytes;
639 remaining -= sg_bytes;
641 if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
646 * Send sequence with transfer sequence initiative in case
647 * this is last FCP frame of the sequence.
650 f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
652 ep = fc_seq_exch(seq);
653 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
654 FC_TYPE_FCP, f_ctl, fh_parm_offset);
657 * send fragment using for a sequence.
659 error = lport->tt.seq_send(lport, seq, fp);
661 WARN_ON(1); /* send error should be rare */
662 fc_fcp_retry_cmd(fsp);
667 fsp->xfer_len += seq_blen; /* premature count? */
672 * fc_fcp_abts_resp() - Send an ABTS response
673 * @fsp: The FCP packet that is being aborted
674 * @fp: The response frame
676 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
679 struct fc_ba_rjt *brp;
680 struct fc_frame_header *fh;
682 fh = fc_frame_header_get(fp);
683 switch (fh->fh_r_ctl) {
687 brp = fc_frame_payload_get(fp, sizeof(*brp));
688 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
693 * we will let the command timeout
694 * and scsi-ml recover in this case,
695 * therefore cleared the ba_done flag.
701 fsp->state |= FC_SRB_ABORTED;
702 fsp->state &= ~FC_SRB_ABORT_PENDING;
704 if (fsp->wait_for_comp)
705 complete(&fsp->tm_done);
707 fc_fcp_complete_locked(fsp);
712 * fc_fcp_recv() - Reveive an FCP frame
713 * @seq: The sequence the frame is on
714 * @fp: The received frame
715 * @arg: The related FCP packet
717 * Context: Called from Soft IRQ context. Can not be called
718 * holding the FCP packet list lock.
720 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
722 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
723 struct fc_lport *lport = fsp->lp;
724 struct fc_frame_header *fh;
725 struct fcp_txrdy *dd;
730 fc_fcp_error(fsp, fp);
734 fh = fc_frame_header_get(fp);
735 r_ctl = fh->fh_r_ctl;
737 if (!(lport->state & LPORT_ST_READY))
739 if (fc_fcp_lock_pkt(fsp))
741 fsp->last_pkt_time = jiffies;
743 if (fh->fh_type == FC_TYPE_BLS) {
744 fc_fcp_abts_resp(fsp, fp);
748 if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
751 if (r_ctl == FC_RCTL_DD_DATA_DESC) {
753 * received XFER RDY from the target
754 * need to send data to the target
756 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
757 dd = fc_frame_payload_get(fp, sizeof(*dd));
760 rc = fc_fcp_send_data(fsp, seq,
761 (size_t) ntohl(dd->ft_data_ro),
762 (size_t) ntohl(dd->ft_burst_len));
764 seq->rec_data = fsp->xfer_len;
765 } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
767 * received a DATA frame
768 * next we will copy the data to the system buffer
770 WARN_ON(fr_len(fp) < sizeof(*fh)); /* len may be 0 */
771 fc_fcp_recv_data(fsp, fp);
772 seq->rec_data = fsp->xfer_contig_end;
773 } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
774 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
776 fc_fcp_resp(fsp, fp);
778 FC_FCP_DBG(fsp, "unexpected frame. r_ctl %x\n", r_ctl);
781 fc_fcp_unlock_pkt(fsp);
787 * fc_fcp_resp() - Handler for FCP responses
788 * @fsp: The FCP packet the response is for
789 * @fp: The response frame
791 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
793 struct fc_frame_header *fh;
794 struct fcp_resp *fc_rp;
795 struct fcp_resp_ext *rp_ex;
796 struct fcp_resp_rsp_info *fc_rp_info;
804 fh = (struct fc_frame_header *)fr_hdr(fp);
805 if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
808 fc_rp = (struct fcp_resp *)(fh + 1);
809 fsp->cdb_status = fc_rp->fr_status;
810 flags = fc_rp->fr_flags;
811 fsp->scsi_comp_flags = flags;
812 expected_len = fsp->data_len;
814 /* if ddp, update xfer len */
815 fc_fcp_ddp_done(fsp);
817 if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
818 rp_ex = (void *)(fc_rp + 1);
819 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
820 if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
822 fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
823 if (flags & FCP_RSP_LEN_VAL) {
824 respl = ntohl(rp_ex->fr_rsp_len);
825 if (respl != sizeof(*fc_rp_info))
827 if (fsp->wait_for_comp) {
828 /* Abuse cdb_status for rsp code */
829 fsp->cdb_status = fc_rp_info->rsp_code;
830 complete(&fsp->tm_done);
832 * tmfs will not have any scsi cmd so
839 if (flags & FCP_SNS_LEN_VAL) {
840 snsl = ntohl(rp_ex->fr_sns_len);
841 if (snsl > SCSI_SENSE_BUFFERSIZE)
842 snsl = SCSI_SENSE_BUFFERSIZE;
843 memcpy(fsp->cmd->sense_buffer,
844 (char *)fc_rp_info + respl, snsl);
847 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
848 if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
850 if (flags & FCP_RESID_UNDER) {
851 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
853 * The cmnd->underflow is the minimum number of
854 * bytes that must be transfered for this
855 * command. Provided a sense condition is not
856 * present, make sure the actual amount
857 * transferred is at least the underflow value
860 if (!(flags & FCP_SNS_LEN_VAL) &&
861 (fc_rp->fr_status == 0) &&
862 (scsi_bufflen(fsp->cmd) -
863 fsp->scsi_resid) < fsp->cmd->underflow)
865 expected_len -= fsp->scsi_resid;
867 fsp->status_code = FC_ERROR;
871 fsp->state |= FC_SRB_RCV_STATUS;
874 * Check for missing or extra data frames.
876 if (unlikely(fsp->xfer_len != expected_len)) {
877 if (fsp->xfer_len < expected_len) {
879 * Some data may be queued locally,
880 * Wait a at least one jiffy to see if it is delivered.
881 * If this expires without data, we may do SRR.
883 fc_fcp_timer_set(fsp, 2);
886 fsp->status_code = FC_DATA_OVRRUN;
887 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
888 "len %x, data len %x\n",
890 fsp->xfer_len, expected_len, fsp->data_len);
892 fc_fcp_complete_locked(fsp);
896 FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
897 "snsl %u\n", flags, fr_len(fp), respl, snsl);
899 fsp->status_code = FC_ERROR;
900 fc_fcp_complete_locked(fsp);
904 * fc_fcp_complete_locked() - Complete processing of a fcp_pkt with the
906 * @fsp: The FCP packet to be completed
908 * This function may sleep if a timer is pending. The packet lock must be
909 * held, and the host lock must not be held.
911 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
913 struct fc_lport *lport = fsp->lp;
918 if (fsp->state & FC_SRB_ABORT_PENDING)
921 if (fsp->state & FC_SRB_ABORTED) {
922 if (!fsp->status_code)
923 fsp->status_code = FC_CMD_ABORTED;
926 * Test for transport underrun, independent of response
929 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
930 (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
931 fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
932 fsp->status_code = FC_DATA_UNDRUN;
940 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
941 struct fc_frame *conf_frame;
944 csp = lport->tt.seq_start_next(seq);
945 conf_frame = fc_fcp_frame_alloc(fsp->lp, 0);
947 f_ctl = FC_FC_SEQ_INIT;
948 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
949 ep = fc_seq_exch(seq);
950 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
952 FC_TYPE_FCP, f_ctl, 0);
953 lport->tt.seq_send(lport, csp, conf_frame);
956 lport->tt.exch_done(seq);
962 * fc_fcp_cleanup_cmd() - Cancel the active exchange on a fcp_pkt
963 * @fsp: The FCP packet whose exchanges should be canceled
964 * @error: The reason for the cancellation
966 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
968 struct fc_lport *lport = fsp->lp;
971 lport->tt.exch_done(fsp->seq_ptr);
974 fsp->status_code = error;
978 * fc_fcp_cleanup_each_cmd() - Cancel all exchanges on a local port
979 * @lport: The local port whose exchanges should be canceled
980 * @id: The target's ID
982 * @error: The reason for cancellation
984 * If lun or id is -1, they are ignored.
986 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lport, unsigned int id,
987 unsigned int lun, int error)
989 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
990 struct fc_fcp_pkt *fsp;
991 struct scsi_cmnd *sc_cmd;
994 spin_lock_irqsave(&si->scsi_queue_lock, flags);
996 list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
998 if (id != -1 && scmd_id(sc_cmd) != id)
1001 if (lun != -1 && sc_cmd->device->lun != lun)
1004 fc_fcp_pkt_hold(fsp);
1005 spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1007 if (!fc_fcp_lock_pkt(fsp)) {
1008 fc_fcp_cleanup_cmd(fsp, error);
1010 fc_fcp_unlock_pkt(fsp);
1013 fc_fcp_pkt_release(fsp);
1014 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1016 * while we dropped the lock multiple pkts could
1017 * have been released, so we have to start over.
1021 spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1025 * fc_fcp_abort_io() - Abort all FCP-SCSI exchanges on a local port
1026 * @lport: The local port whose exchanges are to be aborted
1028 static void fc_fcp_abort_io(struct fc_lport *lport)
1030 fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_HRD_ERROR);
1034 * fc_fcp_pkt_send() - Send a fcp_pkt
1035 * @lport: The local port to send the FCP packet on
1036 * @fsp: The FCP packet to send
1038 * Return: Zero for success and -1 for failure
1039 * Locks: Called without locks held
1041 static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
1043 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1044 unsigned long flags;
1047 fsp->cmd->SCp.ptr = (char *)fsp;
1048 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1049 fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1051 int_to_scsilun(fsp->cmd->device->lun,
1052 (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1053 memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1055 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1056 list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1057 spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1058 rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv);
1060 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1061 list_del(&fsp->list);
1062 spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1069 * fc_fcp_cmd_send() - Send a FCP command
1070 * @lport: The local port to send the command on
1071 * @fsp: The FCP packet the command is on
1072 * @resp: The handler for the response
1074 static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1075 void (*resp)(struct fc_seq *,
1076 struct fc_frame *fp,
1079 struct fc_frame *fp;
1081 struct fc_rport *rport;
1082 struct fc_rport_libfc_priv *rpriv;
1083 const size_t len = sizeof(fsp->cdb_cmd);
1086 if (fc_fcp_lock_pkt(fsp))
1089 fp = fc_fcp_frame_alloc(lport, sizeof(fsp->cdb_cmd));
1095 memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1098 fsp->max_payload = rport->maxframe_size;
1099 rpriv = rport->dd_data;
1101 fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1102 fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP,
1103 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1105 seq = lport->tt.exch_seq_send(lport, fp, resp, fc_fcp_pkt_destroy,
1111 fsp->last_pkt_time = jiffies;
1113 fc_fcp_pkt_hold(fsp); /* hold for fc_fcp_pkt_destroy */
1115 setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1116 fc_fcp_timer_set(fsp,
1117 (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1118 FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1120 fc_fcp_unlock_pkt(fsp);
1125 * fc_fcp_error() - Handler for FCP layer errors
1126 * @fsp: The FCP packet the error is on
1127 * @fp: The frame that has errored
1129 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1131 int error = PTR_ERR(fp);
1133 if (fc_fcp_lock_pkt(fsp))
1136 if (error == -FC_EX_CLOSED) {
1137 fc_fcp_retry_cmd(fsp);
1142 * clear abort pending, because the lower layer
1143 * decided to force completion.
1145 fsp->state &= ~FC_SRB_ABORT_PENDING;
1146 fsp->status_code = FC_CMD_PLOGO;
1147 fc_fcp_complete_locked(fsp);
1149 fc_fcp_unlock_pkt(fsp);
1153 * fc_fcp_pkt_abort() - Abort a fcp_pkt
1154 * @fsp: The FCP packet to abort on
1156 * Called to send an abort and then wait for abort completion
1158 static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1162 if (fc_fcp_send_abort(fsp))
1165 init_completion(&fsp->tm_done);
1166 fsp->wait_for_comp = 1;
1168 spin_unlock_bh(&fsp->scsi_pkt_lock);
1169 rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1170 spin_lock_bh(&fsp->scsi_pkt_lock);
1171 fsp->wait_for_comp = 0;
1174 FC_FCP_DBG(fsp, "target abort cmd failed\n");
1176 } else if (fsp->state & FC_SRB_ABORTED) {
1177 FC_FCP_DBG(fsp, "target abort cmd passed\n");
1179 fc_fcp_complete_locked(fsp);
1186 * fc_lun_reset_send() - Send LUN reset command
1187 * @data: The FCP packet that identifies the LUN to be reset
1189 static void fc_lun_reset_send(unsigned long data)
1191 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1192 struct fc_lport *lport = fsp->lp;
1193 if (lport->tt.fcp_cmd_send(lport, fsp, fc_tm_done)) {
1194 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1196 if (fc_fcp_lock_pkt(fsp))
1198 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1199 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1200 fc_fcp_unlock_pkt(fsp);
1205 * fc_lun_reset() - Send a LUN RESET command to a device
1206 * and wait for the reply
1207 * @lport: The local port to sent the comand on
1208 * @fsp: The FCP packet that identifies the LUN to be reset
1209 * @id: The SCSI command ID
1210 * @lun: The LUN ID to be reset
1212 static int fc_lun_reset(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1213 unsigned int id, unsigned int lun)
1217 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1218 fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1219 int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1221 fsp->wait_for_comp = 1;
1222 init_completion(&fsp->tm_done);
1224 fc_lun_reset_send((unsigned long)fsp);
1227 * wait for completion of reset
1228 * after that make sure all commands are terminated
1230 rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1232 spin_lock_bh(&fsp->scsi_pkt_lock);
1233 fsp->state |= FC_SRB_COMPL;
1234 spin_unlock_bh(&fsp->scsi_pkt_lock);
1236 del_timer_sync(&fsp->timer);
1238 spin_lock_bh(&fsp->scsi_pkt_lock);
1240 lport->tt.exch_done(fsp->seq_ptr);
1241 fsp->seq_ptr = NULL;
1243 fsp->wait_for_comp = 0;
1244 spin_unlock_bh(&fsp->scsi_pkt_lock);
1247 FC_SCSI_DBG(lport, "lun reset failed\n");
1251 /* cdb_status holds the tmf's rsp code */
1252 if (fsp->cdb_status != FCP_TMF_CMPL)
1255 FC_SCSI_DBG(lport, "lun reset to lun %u completed\n", lun);
1256 fc_fcp_cleanup_each_cmd(lport, id, lun, FC_CMD_ABORTED);
1261 * fc_tm_done() - Task Managment response handler
1262 * @seq: The sequence that the response is on
1263 * @fp: The response frame
1264 * @arg: The FCP packet the response is for
1266 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1268 struct fc_fcp_pkt *fsp = arg;
1269 struct fc_frame_header *fh;
1273 * If there is an error just let it timeout or wait
1274 * for TMF to be aborted if it timedout.
1276 * scsi-eh will escalate for when either happens.
1281 if (fc_fcp_lock_pkt(fsp))
1285 * raced with eh timeout handler.
1287 if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1288 spin_unlock_bh(&fsp->scsi_pkt_lock);
1292 fh = fc_frame_header_get(fp);
1293 if (fh->fh_type != FC_TYPE_BLS)
1294 fc_fcp_resp(fsp, fp);
1295 fsp->seq_ptr = NULL;
1296 fsp->lp->tt.exch_done(seq);
1298 fc_fcp_unlock_pkt(fsp);
1302 * fc_fcp_cleanup() - Cleanup all FCP exchanges on a local port
1303 * @lport: The local port to be cleaned up
1305 static void fc_fcp_cleanup(struct fc_lport *lport)
1307 fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_ERROR);
1311 * fc_fcp_timeout() - Handler for fcp_pkt timeouts
1312 * @data: The FCP packet that has timed out
1314 * If REC is supported then just issue it and return. The REC exchange will
1315 * complete or time out and recovery can continue at that point. Otherwise,
1316 * if the response has been received without all the data it has been
1317 * ER_TIMEOUT since the response was received. If the response has not been
1318 * received we see if data was received recently. If it has been then we
1319 * continue waiting, otherwise, we abort the command.
1321 static void fc_fcp_timeout(unsigned long data)
1323 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1324 struct fc_rport *rport = fsp->rport;
1325 struct fc_rport_libfc_priv *rpriv = rport->dd_data;
1327 if (fc_fcp_lock_pkt(fsp))
1330 if (fsp->cdb_cmd.fc_tm_flags)
1333 fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1335 if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
1337 else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1339 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1340 else if (fsp->state & FC_SRB_RCV_STATUS)
1341 fc_fcp_complete_locked(fsp);
1343 fc_timeout_error(fsp);
1344 fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1346 fc_fcp_unlock_pkt(fsp);
1350 * fc_fcp_rec() - Send a REC ELS request
1351 * @fsp: The FCP packet to send the REC request on
1353 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1355 struct fc_lport *lport;
1356 struct fc_frame *fp;
1357 struct fc_rport *rport;
1358 struct fc_rport_libfc_priv *rpriv;
1362 rpriv = rport->dd_data;
1363 if (!fsp->seq_ptr || rpriv->rp_state != RPORT_ST_READY) {
1364 fsp->status_code = FC_HRD_ERROR;
1366 fc_fcp_complete_locked(fsp);
1369 fp = fc_fcp_frame_alloc(lport, sizeof(struct fc_els_rec));
1373 fr_seq(fp) = fsp->seq_ptr;
1374 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1375 fc_host_port_id(rpriv->local_port->host), FC_TYPE_ELS,
1376 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1377 if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC,
1378 fc_fcp_rec_resp, fsp,
1379 jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1380 fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */
1384 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1385 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1387 fc_timeout_error(fsp);
1391 * fc_fcp_rec_resp() - Handler for REC ELS responses
1392 * @seq: The sequence the response is on
1393 * @fp: The response frame
1394 * @arg: The FCP packet the response is on
1396 * If the response is a reject then the scsi layer will handle
1397 * the timeout. If the response is a LS_ACC then if the I/O was not completed
1398 * set the timeout and return. If the I/O was completed then complete the
1399 * exchange and tell the SCSI layer.
1401 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1403 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1404 struct fc_els_rec_acc *recp;
1405 struct fc_els_ls_rjt *rjt;
1409 enum dma_data_direction data_dir;
1411 struct fc_rport_libfc_priv *rpriv;
1414 fc_fcp_rec_error(fsp, fp);
1418 if (fc_fcp_lock_pkt(fsp))
1421 fsp->recov_retry = 0;
1422 opcode = fc_frame_payload_op(fp);
1423 if (opcode == ELS_LS_RJT) {
1424 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1425 switch (rjt->er_reason) {
1427 FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1428 "reason %d expl %d\n",
1429 fsp->rport->port_id, rjt->er_reason,
1433 FC_FCP_DBG(fsp, "device does not support REC\n");
1434 rpriv = fsp->rport->dd_data;
1436 * if we do not spport RECs or got some bogus
1437 * reason then resetup timer so we check for
1440 rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1441 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1446 * If no data transfer, the command frame got dropped
1447 * so we just retry. If data was transferred, we
1448 * lost the response but the target has no record,
1449 * so we abort and retry.
1451 if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1452 fsp->xfer_len == 0) {
1453 fc_fcp_retry_cmd(fsp);
1456 fc_timeout_error(fsp);
1459 } else if (opcode == ELS_LS_ACC) {
1460 if (fsp->state & FC_SRB_ABORTED)
1463 data_dir = fsp->cmd->sc_data_direction;
1464 recp = fc_frame_payload_get(fp, sizeof(*recp));
1465 offset = ntohl(recp->reca_fc4value);
1466 e_stat = ntohl(recp->reca_e_stat);
1468 if (e_stat & ESB_ST_COMPLETE) {
1471 * The exchange is complete.
1473 * For output, we must've lost the response.
1474 * For input, all data must've been sent.
1475 * We lost may have lost the response
1476 * (and a confirmation was requested) and maybe
1479 * If all data received, send SRR
1480 * asking for response. If partial data received,
1481 * or gaps, SRR requests data at start of gap.
1482 * Recovery via SRR relies on in-order-delivery.
1484 if (data_dir == DMA_TO_DEVICE) {
1485 r_ctl = FC_RCTL_DD_CMD_STATUS;
1486 } else if (fsp->xfer_contig_end == offset) {
1487 r_ctl = FC_RCTL_DD_CMD_STATUS;
1489 offset = fsp->xfer_contig_end;
1490 r_ctl = FC_RCTL_DD_SOL_DATA;
1492 fc_fcp_srr(fsp, r_ctl, offset);
1493 } else if (e_stat & ESB_ST_SEQ_INIT) {
1496 * The remote port has the initiative, so just
1497 * keep waiting for it to complete.
1499 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1503 * The exchange is incomplete, we have seq. initiative.
1504 * Lost response with requested confirmation,
1505 * lost confirmation, lost transfer ready or
1508 * For output, if not all data was received, ask
1509 * for transfer ready to be repeated.
1511 * If we received or sent all the data, send SRR to
1514 * If we lost a response, we may have lost some read
1517 r_ctl = FC_RCTL_DD_SOL_DATA;
1518 if (data_dir == DMA_TO_DEVICE) {
1519 r_ctl = FC_RCTL_DD_CMD_STATUS;
1520 if (offset < fsp->data_len)
1521 r_ctl = FC_RCTL_DD_DATA_DESC;
1522 } else if (offset == fsp->xfer_contig_end) {
1523 r_ctl = FC_RCTL_DD_CMD_STATUS;
1524 } else if (fsp->xfer_contig_end < offset) {
1525 offset = fsp->xfer_contig_end;
1527 fc_fcp_srr(fsp, r_ctl, offset);
1531 fc_fcp_unlock_pkt(fsp);
1533 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1538 * fc_fcp_rec_error() - Handler for REC errors
1539 * @fsp: The FCP packet the error is on
1540 * @fp: The REC frame
1542 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1544 int error = PTR_ERR(fp);
1546 if (fc_fcp_lock_pkt(fsp))
1551 fc_fcp_retry_cmd(fsp);
1555 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1556 fsp, fsp->rport->port_id, error);
1557 fsp->status_code = FC_CMD_PLOGO;
1560 case -FC_EX_TIMEOUT:
1562 * Assume REC or LS_ACC was lost.
1563 * The exchange manager will have aborted REC, so retry.
1565 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1566 fsp->rport->port_id, error, fsp->recov_retry,
1567 FC_MAX_RECOV_RETRY);
1568 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1571 fc_timeout_error(fsp);
1574 fc_fcp_unlock_pkt(fsp);
1576 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1580 * fc_timeout_error() - Handler for fcp_pkt timeouts
1581 * @fsp: The FCP packt that has timed out
1583 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1585 fsp->status_code = FC_CMD_TIME_OUT;
1586 fsp->cdb_status = 0;
1589 * if this fails then we let the scsi command timer fire and
1592 fc_fcp_send_abort(fsp);
1596 * fc_fcp_srr() - Send a SRR request (Sequence Retransmission Request)
1597 * @fsp: The FCP packet the SRR is to be sent on
1598 * @r_ctl: The R_CTL field for the SRR request
1599 * This is called after receiving status but insufficient data, or
1600 * when expecting status but the request has timed out.
1602 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1604 struct fc_lport *lport = fsp->lp;
1605 struct fc_rport *rport;
1606 struct fc_rport_libfc_priv *rpriv;
1607 struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1609 struct fcp_srr *srr;
1610 struct fc_frame *fp;
1614 rpriv = rport->dd_data;
1615 cdb_op = fsp->cdb_cmd.fc_cdb[0];
1617 if (!(rpriv->flags & FC_RP_FLAGS_RETRY) ||
1618 rpriv->rp_state != RPORT_ST_READY)
1619 goto retry; /* shouldn't happen */
1620 fp = fc_fcp_frame_alloc(lport, sizeof(*srr));
1624 srr = fc_frame_payload_get(fp, sizeof(*srr));
1625 memset(srr, 0, sizeof(*srr));
1626 srr->srr_op = ELS_SRR;
1627 srr->srr_ox_id = htons(ep->oxid);
1628 srr->srr_rx_id = htons(ep->rxid);
1629 srr->srr_r_ctl = r_ctl;
1630 srr->srr_rel_off = htonl(offset);
1632 fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1633 fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP,
1634 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1636 seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, NULL,
1637 fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1641 fsp->recov_seq = seq;
1642 fsp->xfer_len = offset;
1643 fsp->xfer_contig_end = offset;
1644 fsp->state &= ~FC_SRB_RCV_STATUS;
1645 fc_fcp_pkt_hold(fsp); /* hold for outstanding SRR */
1648 fc_fcp_retry_cmd(fsp);
1652 * fc_fcp_srr_resp() - Handler for SRR response
1653 * @seq: The sequence the SRR is on
1654 * @fp: The SRR frame
1655 * @arg: The FCP packet the SRR is on
1657 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1659 struct fc_fcp_pkt *fsp = arg;
1660 struct fc_frame_header *fh;
1663 fc_fcp_srr_error(fsp, fp);
1667 if (fc_fcp_lock_pkt(fsp))
1670 fh = fc_frame_header_get(fp);
1672 * BUG? fc_fcp_srr_error calls exch_done which would release
1673 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1674 * then fc_exch_timeout would be sending an abort. The exch_done
1675 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1676 * an abort response though.
1678 if (fh->fh_type == FC_TYPE_BLS) {
1679 fc_fcp_unlock_pkt(fsp);
1683 fsp->recov_seq = NULL;
1684 switch (fc_frame_payload_op(fp)) {
1686 fsp->recov_retry = 0;
1687 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1691 fc_timeout_error(fsp);
1694 fc_fcp_unlock_pkt(fsp);
1695 fsp->lp->tt.exch_done(seq);
1698 fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */
1702 * fc_fcp_srr_error() - Handler for SRR errors
1703 * @fsp: The FCP packet that the SRR error is on
1704 * @fp: The SRR frame
1706 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1708 if (fc_fcp_lock_pkt(fsp))
1710 fsp->lp->tt.exch_done(fsp->recov_seq);
1711 fsp->recov_seq = NULL;
1712 switch (PTR_ERR(fp)) {
1713 case -FC_EX_TIMEOUT:
1714 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1717 fc_timeout_error(fsp);
1719 case -FC_EX_CLOSED: /* e.g., link failure */
1722 fc_fcp_retry_cmd(fsp);
1725 fc_fcp_unlock_pkt(fsp);
1727 fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */
1731 * fc_fcp_lport_queue_ready() - Determine if the lport and it's queue is ready
1732 * @lport: The local port to be checked
1734 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lport)
1737 return (lport->state == LPORT_ST_READY) &&
1738 lport->link_up && !lport->qfull;
1742 * fc_queuecommand() - The queuecommand function of the SCSI template
1743 * @cmd: The scsi_cmnd to be executed
1744 * @done: The callback function to be called when the scsi_cmnd is complete
1746 * This is the i/o strategy routine, called by the SCSI layer. This routine
1747 * is called with the host_lock held.
1749 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1751 struct fc_lport *lport;
1752 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1753 struct fc_fcp_pkt *fsp;
1754 struct fc_rport_libfc_priv *rpriv;
1757 struct fcoe_dev_stats *stats;
1759 lport = shost_priv(sc_cmd->device->host);
1760 spin_unlock_irq(lport->host->host_lock);
1762 rval = fc_remote_port_chkready(rport);
1764 sc_cmd->result = rval;
1769 if (!*(struct fc_remote_port **)rport->dd_data) {
1771 * rport is transitioning from blocked/deleted to
1774 sc_cmd->result = DID_IMM_RETRY << 16;
1779 rpriv = rport->dd_data;
1781 if (!fc_fcp_lport_queue_ready(lport)) {
1783 fc_fcp_can_queue_ramp_down(lport);
1784 rc = SCSI_MLQUEUE_HOST_BUSY;
1788 fsp = fc_fcp_pkt_alloc(lport, GFP_ATOMIC);
1790 rc = SCSI_MLQUEUE_HOST_BUSY;
1795 * build the libfc request pkt
1797 fsp->cmd = sc_cmd; /* save the cmd */
1798 fsp->lp = lport; /* save the softc ptr */
1799 fsp->rport = rport; /* set the remote port ptr */
1800 fsp->xfer_ddp = FC_XID_UNKNOWN;
1801 sc_cmd->scsi_done = done;
1804 * set up the transfer length
1806 fsp->data_len = scsi_bufflen(sc_cmd);
1810 * setup the data direction
1812 stats = fc_lport_get_stats(lport);
1813 if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1814 fsp->req_flags = FC_SRB_READ;
1815 stats->InputRequests++;
1816 stats->InputMegabytes = fsp->data_len;
1817 } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1818 fsp->req_flags = FC_SRB_WRITE;
1819 stats->OutputRequests++;
1820 stats->OutputMegabytes = fsp->data_len;
1823 stats->ControlRequests++;
1826 fsp->tgt_flags = rpriv->flags;
1828 init_timer(&fsp->timer);
1829 fsp->timer.data = (unsigned long)fsp;
1832 * send it to the lower layer
1833 * if we get -1 return then put the request in the pending
1836 rval = fc_fcp_pkt_send(lport, fsp);
1838 fsp->state = FC_SRB_FREE;
1839 fc_fcp_pkt_release(fsp);
1840 rc = SCSI_MLQUEUE_HOST_BUSY;
1843 spin_lock_irq(lport->host->host_lock);
1846 EXPORT_SYMBOL(fc_queuecommand);
1849 * fc_io_compl() - Handle responses for completed commands
1850 * @fsp: The FCP packet that is complete
1852 * Translates fcp_pkt errors to a Linux SCSI errors.
1853 * The fcp packet lock must be held when calling.
1855 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1857 struct fc_fcp_internal *si;
1858 struct scsi_cmnd *sc_cmd;
1859 struct fc_lport *lport;
1860 unsigned long flags;
1862 /* release outstanding ddp context */
1863 fc_fcp_ddp_done(fsp);
1865 fsp->state |= FC_SRB_COMPL;
1866 if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1867 spin_unlock_bh(&fsp->scsi_pkt_lock);
1868 del_timer_sync(&fsp->timer);
1869 spin_lock_bh(&fsp->scsi_pkt_lock);
1873 si = fc_get_scsi_internal(lport);
1878 * if can_queue ramp down is done then try can_queue ramp up
1879 * since commands are completing now.
1881 if (si->last_can_queue_ramp_down_time)
1882 fc_fcp_can_queue_ramp_up(lport);
1887 if (!sc_cmd->SCp.ptr)
1890 CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1891 switch (fsp->status_code) {
1893 if (fsp->cdb_status == 0) {
1897 sc_cmd->result = DID_OK << 16;
1898 if (fsp->scsi_resid)
1899 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1902 * transport level I/O was ok but scsi
1903 * has non zero status
1905 sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1909 sc_cmd->result = DID_ERROR << 16;
1911 case FC_DATA_UNDRUN:
1912 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1914 * scsi status is good but transport level
1917 sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ?
1918 DID_OK : DID_ERROR) << 16;
1921 * scsi got underrun, this is an error
1923 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1924 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1927 case FC_DATA_OVRRUN:
1929 * overrun is an error
1931 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1933 case FC_CMD_ABORTED:
1934 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1936 case FC_CMD_TIME_OUT:
1937 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1940 sc_cmd->result = (DID_RESET << 16);
1943 sc_cmd->result = (DID_NO_CONNECT << 16);
1946 sc_cmd->result = (DID_ERROR << 16);
1950 spin_lock_irqsave(&si->scsi_queue_lock, flags);
1951 list_del(&fsp->list);
1952 spin_unlock_irqrestore(&si->scsi_queue_lock, flags);
1953 sc_cmd->SCp.ptr = NULL;
1954 sc_cmd->scsi_done(sc_cmd);
1956 /* release ref from initial allocation in queue command */
1957 fc_fcp_pkt_release(fsp);
1961 * fc_eh_abort() - Abort a command
1962 * @sc_cmd: The SCSI command to abort
1964 * From SCSI host template.
1965 * Send an ABTS to the target device and wait for the response.
1967 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1969 struct fc_fcp_pkt *fsp;
1970 struct fc_lport *lport;
1972 unsigned long flags;
1974 lport = shost_priv(sc_cmd->device->host);
1975 if (lport->state != LPORT_ST_READY)
1977 else if (!lport->link_up)
1980 spin_lock_irqsave(lport->host->host_lock, flags);
1981 fsp = CMD_SP(sc_cmd);
1983 /* command completed while scsi eh was setting up */
1984 spin_unlock_irqrestore(lport->host->host_lock, flags);
1987 /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1988 fc_fcp_pkt_hold(fsp);
1989 spin_unlock_irqrestore(lport->host->host_lock, flags);
1991 if (fc_fcp_lock_pkt(fsp)) {
1992 /* completed while we were waiting for timer to be deleted */
1997 rc = fc_fcp_pkt_abort(fsp);
1998 fc_fcp_unlock_pkt(fsp);
2001 fc_fcp_pkt_release(fsp);
2004 EXPORT_SYMBOL(fc_eh_abort);
2007 * fc_eh_device_reset() - Reset a single LUN
2008 * @sc_cmd: The SCSI command which identifies the device whose
2009 * LUN is to be reset
2011 * Set from SCSI host template.
2013 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
2015 struct fc_lport *lport;
2016 struct fc_fcp_pkt *fsp;
2017 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
2021 rval = fc_remote_port_chkready(rport);
2025 lport = shost_priv(sc_cmd->device->host);
2027 if (lport->state != LPORT_ST_READY)
2030 FC_SCSI_DBG(lport, "Resetting rport (%6x)\n", rport->port_id);
2032 fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO);
2034 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
2039 * Build the libfc request pkt. Do not set the scsi cmnd, because
2040 * the sc passed in is not setup for execution like when sent
2041 * through the queuecommand callout.
2043 fsp->lp = lport; /* save the softc ptr */
2044 fsp->rport = rport; /* set the remote port ptr */
2047 * flush outstanding commands
2049 rc = fc_lun_reset(lport, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2050 fsp->state = FC_SRB_FREE;
2051 fc_fcp_pkt_release(fsp);
2056 EXPORT_SYMBOL(fc_eh_device_reset);
2059 * fc_eh_host_reset() - Reset a Scsi_Host.
2060 * @sc_cmd: The SCSI command that identifies the SCSI host to be reset
2062 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2064 struct Scsi_Host *shost = sc_cmd->device->host;
2065 struct fc_lport *lport = shost_priv(shost);
2066 unsigned long wait_tmo;
2068 FC_SCSI_DBG(lport, "Resetting host\n");
2070 lport->tt.lport_reset(lport);
2071 wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2072 while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies,
2076 if (fc_fcp_lport_queue_ready(lport)) {
2077 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2078 "on port (%6x)\n", fc_host_port_id(lport->host));
2081 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2082 "port (%6x) is not ready.\n",
2083 fc_host_port_id(lport->host));
2087 EXPORT_SYMBOL(fc_eh_host_reset);
2090 * fc_slave_alloc() - Configure the queue depth of a Scsi_Host
2091 * @sdev: The SCSI device that identifies the SCSI host
2093 * Configures queue depth based on host's cmd_per_len. If not set
2094 * then we use the libfc default.
2096 int fc_slave_alloc(struct scsi_device *sdev)
2098 struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2100 if (!rport || fc_remote_port_chkready(rport))
2103 if (sdev->tagged_supported)
2104 scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2106 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
2107 FC_FCP_DFLT_QUEUE_DEPTH);
2111 EXPORT_SYMBOL(fc_slave_alloc);
2114 * fc_change_queue_depth() - Change a device's queue depth
2115 * @sdev: The SCSI device whose queue depth is to change
2116 * @qdepth: The new queue depth
2117 * @reason: The resason for the change
2119 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
2122 case SCSI_QDEPTH_DEFAULT:
2123 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2125 case SCSI_QDEPTH_QFULL:
2126 scsi_track_queue_full(sdev, qdepth);
2128 case SCSI_QDEPTH_RAMP_UP:
2129 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2134 return sdev->queue_depth;
2136 EXPORT_SYMBOL(fc_change_queue_depth);
2139 * fc_change_queue_type() - Change a device's queue type
2140 * @sdev: The SCSI device whose queue depth is to change
2141 * @tag_type: Identifier for queue type
2143 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2145 if (sdev->tagged_supported) {
2146 scsi_set_tag_type(sdev, tag_type);
2148 scsi_activate_tcq(sdev, sdev->queue_depth);
2150 scsi_deactivate_tcq(sdev, sdev->queue_depth);
2156 EXPORT_SYMBOL(fc_change_queue_type);
2159 * fc_fcp_destory() - Tear down the FCP layer for a given local port
2160 * @lport: The local port that no longer needs the FCP layer
2162 void fc_fcp_destroy(struct fc_lport *lport)
2164 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
2166 if (!list_empty(&si->scsi_pkt_queue))
2167 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2168 "port (%6x)\n", fc_host_port_id(lport->host));
2170 mempool_destroy(si->scsi_pkt_pool);
2172 lport->scsi_priv = NULL;
2174 EXPORT_SYMBOL(fc_fcp_destroy);
2180 scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2181 sizeof(struct fc_fcp_pkt),
2182 0, SLAB_HWCACHE_ALIGN, NULL);
2183 if (!scsi_pkt_cachep) {
2184 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2185 "module load failed!");
2192 void fc_destroy_fcp()
2194 if (scsi_pkt_cachep)
2195 kmem_cache_destroy(scsi_pkt_cachep);
2199 * fc_fcp_init() - Initialize the FCP layer for a local port
2200 * @lport: The local port to initialize the exchange layer for
2202 int fc_fcp_init(struct fc_lport *lport)
2205 struct fc_fcp_internal *si;
2207 if (!lport->tt.fcp_cmd_send)
2208 lport->tt.fcp_cmd_send = fc_fcp_cmd_send;
2210 if (!lport->tt.fcp_cleanup)
2211 lport->tt.fcp_cleanup = fc_fcp_cleanup;
2213 if (!lport->tt.fcp_abort_io)
2214 lport->tt.fcp_abort_io = fc_fcp_abort_io;
2216 si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2219 lport->scsi_priv = si;
2220 si->max_can_queue = lport->host->can_queue;
2221 INIT_LIST_HEAD(&si->scsi_pkt_queue);
2222 spin_lock_init(&si->scsi_queue_lock);
2224 si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2225 if (!si->scsi_pkt_pool) {
2235 EXPORT_SYMBOL(fc_fcp_init);