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 acknowleged */
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 */
55 #define FC_SRB_NOMEM (1 << 7) /* dropped to out of mem */
57 #define FC_SRB_READ (1 << 1)
58 #define FC_SRB_WRITE (1 << 0)
61 * The SCp.ptr should be tested and set under the host lock. NULL indicates
62 * that the command has been retruned to the scsi layer.
64 #define CMD_SP(Cmnd) ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
65 #define CMD_ENTRY_STATUS(Cmnd) ((Cmnd)->SCp.have_data_in)
66 #define CMD_COMPL_STATUS(Cmnd) ((Cmnd)->SCp.this_residual)
67 #define CMD_SCSI_STATUS(Cmnd) ((Cmnd)->SCp.Status)
68 #define CMD_RESID_LEN(Cmnd) ((Cmnd)->SCp.buffers_residual)
71 * struct fc_fcp_internal - FCP layer internal data
72 * @scsi_pkt_pool: Memory pool to draw FCP packets from
73 * @scsi_pkt_queue: Current FCP packets
74 * @throttled: The FCP packet queue is throttled
76 struct fc_fcp_internal {
77 mempool_t *scsi_pkt_pool;
78 struct list_head scsi_pkt_queue;
82 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
86 * FC scsi I/O related functions
88 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
89 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
90 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
91 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
92 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
93 static void fc_fcp_error(struct fc_fcp_pkt *, struct fc_frame *);
94 static void fc_timeout_error(struct fc_fcp_pkt *);
95 static void fc_fcp_timeout(unsigned long);
96 static void fc_fcp_rec(struct fc_fcp_pkt *);
97 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
98 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
99 static void fc_io_compl(struct fc_fcp_pkt *);
101 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
102 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
103 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
106 * command status codes
108 #define FC_COMPLETE 0
109 #define FC_CMD_ABORTED 1
110 #define FC_CMD_RESET 2
111 #define FC_CMD_PLOGO 3
113 #define FC_TRANS_ERR 5
114 #define FC_DATA_OVRRUN 6
115 #define FC_DATA_UNDRUN 7
117 #define FC_HRD_ERROR 9
118 #define FC_CMD_TIME_OUT 10
121 * Error recovery timeout values.
123 #define FC_SCSI_ER_TIMEOUT (10 * HZ)
124 #define FC_SCSI_TM_TOV (10 * HZ)
125 #define FC_SCSI_REC_TOV (2 * HZ)
126 #define FC_HOST_RESET_TIMEOUT (30 * HZ)
128 #define FC_MAX_ERROR_CNT 5
129 #define FC_MAX_RECOV_RETRY 3
131 #define FC_FCP_DFLT_QUEUE_DEPTH 32
134 * fc_fcp_pkt_alloc() - Allocate a fcp_pkt
135 * @lport: The local port that the FCP packet is for
136 * @gfp: GFP flags for allocation
138 * Return value: fcp_pkt structure or null on allocation failure.
139 * Context: Can be called from process context, no lock is required.
141 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lport, gfp_t gfp)
143 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
144 struct fc_fcp_pkt *fsp;
146 fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
148 memset(fsp, 0, sizeof(*fsp));
150 atomic_set(&fsp->ref_cnt, 1);
151 init_timer(&fsp->timer);
152 INIT_LIST_HEAD(&fsp->list);
153 spin_lock_init(&fsp->scsi_pkt_lock);
159 * fc_fcp_pkt_release() - Release hold on a fcp_pkt
160 * @fsp: The FCP packet to be released
162 * Context: Can be called from process or interrupt context,
163 * no lock is required.
165 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
167 if (atomic_dec_and_test(&fsp->ref_cnt)) {
168 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
170 mempool_free(fsp, si->scsi_pkt_pool);
175 * fc_fcp_pkt_hold() - Hold a fcp_pkt
176 * @fsp: The FCP packet to be held
178 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
180 atomic_inc(&fsp->ref_cnt);
184 * fc_fcp_pkt_destory() - Release hold on a fcp_pkt
185 * @seq: The sequence that the FCP packet is on (required by destructor API)
186 * @fsp: The FCP packet to be released
188 * This routine is called by a destructor callback in the exch_seq_send()
189 * routine of the libfc Transport Template. The 'struct fc_seq' is a required
190 * argument even though it is not used by this routine.
192 * Context: No locking required.
194 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
196 fc_fcp_pkt_release(fsp);
200 * fc_fcp_lock_pkt() - Lock a fcp_pkt and increase its reference count
201 * @fsp: The FCP packet to be locked and incremented
203 * We should only return error if we return a command to SCSI-ml before
204 * getting a response. This can happen in cases where we send a abort, but
205 * do not wait for the response and the abort and command can be passing
206 * each other on the wire/network-layer.
208 * Note: this function locks the packet and gets a reference to allow
209 * callers to call the completion function while the lock is held and
210 * not have to worry about the packets refcount.
212 * TODO: Maybe we should just have callers grab/release the lock and
213 * have a function that they call to verify the fsp and grab a ref if
216 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
218 spin_lock_bh(&fsp->scsi_pkt_lock);
219 if (fsp->state & FC_SRB_COMPL) {
220 spin_unlock_bh(&fsp->scsi_pkt_lock);
224 fc_fcp_pkt_hold(fsp);
229 * fc_fcp_unlock_pkt() - Release a fcp_pkt's lock and decrement its
231 * @fsp: The FCP packet to be unlocked and decremented
233 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
235 spin_unlock_bh(&fsp->scsi_pkt_lock);
236 fc_fcp_pkt_release(fsp);
240 * fc_fcp_timer_set() - Start a timer for a fcp_pkt
241 * @fsp: The FCP packet to start a timer for
242 * @delay: The timeout period for the timer
244 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
246 if (!(fsp->state & FC_SRB_COMPL))
247 mod_timer(&fsp->timer, jiffies + delay);
251 * fc_fcp_send_abort() - Send an abort for exchanges associated with a
253 * @fsp: The FCP packet to abort exchanges on
255 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
260 fsp->state |= FC_SRB_ABORT_PENDING;
261 return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
265 * fc_fcp_retry_cmd() - Retry a fcp_pkt
266 * @fsp: The FCP packet to be retried
268 * Sets the status code to be FC_ERROR and then calls
269 * fc_fcp_complete_locked() which in turn calls fc_io_compl().
270 * fc_io_compl() will notify the SCSI-ml that the I/O is done.
271 * The SCSI-ml will retry the command.
273 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
276 fsp->lp->tt.exch_done(fsp->seq_ptr);
280 fsp->state &= ~FC_SRB_ABORT_PENDING;
282 fsp->status_code = FC_ERROR;
283 fc_fcp_complete_locked(fsp);
287 * fc_fcp_ddp_setup() - Calls a LLD's ddp_setup routine to set up DDP context
288 * @fsp: The FCP packet that will manage the DDP frames
289 * @xid: The XID that will be used for the DDP exchange
291 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
293 struct fc_lport *lport;
299 if ((fsp->req_flags & FC_SRB_READ) &&
300 (lport->lro_enabled) && (lport->tt.ddp_setup)) {
301 if (lport->tt.ddp_setup(lport, xid, scsi_sglist(fsp->cmd),
302 scsi_sg_count(fsp->cmd)))
308 * fc_fcp_ddp_done() - Calls a LLD's ddp_done routine to release any
309 * DDP related resources for a fcp_pkt
310 * @fsp: The FCP packet that DDP had been used on
312 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
314 struct fc_lport *lport;
319 if (fsp->xfer_ddp == FC_XID_UNKNOWN)
323 if (lport->tt.ddp_done) {
324 fsp->xfer_len = lport->tt.ddp_done(lport, fsp->xfer_ddp);
325 fsp->xfer_ddp = FC_XID_UNKNOWN;
330 * fc_fcp_can_queue_ramp_down() - reduces can_queue
331 * @lport: lport to reduce can_queue
333 * If we are getting memory allocation failures, then we may
334 * be trying to execute too many commands. We let the running
335 * commands complete or timeout, then try again with a reduced
336 * can_queue. Eventually we will hit the point where we run
337 * on all reserved structs.
339 static void fc_fcp_can_queue_ramp_down(struct fc_lport *lport)
341 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
345 spin_lock_irqsave(lport->host->host_lock, flags);
350 can_queue = lport->host->can_queue;
354 lport->host->can_queue = can_queue;
355 shost_printk(KERN_ERR, lport->host, "libfc: Could not allocate frame.\n"
356 "Reducing can_queue to %d.\n", can_queue);
358 spin_unlock_irqrestore(lport->host->host_lock, flags);
362 * fc_fcp_frame_alloc() - Allocates fc_frame structure and buffer.
363 * @lport: fc lport struct
364 * @len: payload length
366 * Allocates fc_frame structure and buffer but if fails to allocate
367 * then reduce can_queue.
369 static inline struct fc_frame *fc_fcp_frame_alloc(struct fc_lport *lport,
374 fp = fc_frame_alloc(lport, len);
376 fc_fcp_can_queue_ramp_down(lport);
381 * fc_fcp_recv_data() - Handler for receiving SCSI-FCP data from a target
382 * @fsp: The FCP packet the data is on
383 * @fp: The data frame
385 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
387 struct scsi_cmnd *sc = fsp->cmd;
388 struct fc_lport *lport = fsp->lp;
389 struct fcoe_dev_stats *stats;
390 struct fc_frame_header *fh;
397 struct scatterlist *sg;
400 fh = fc_frame_header_get(fp);
401 offset = ntohl(fh->fh_parm_offset);
402 start_offset = offset;
403 len = fr_len(fp) - sizeof(*fh);
404 buf = fc_frame_payload_get(fp, 0);
406 /* if this I/O is ddped, update xfer len */
407 fc_fcp_ddp_done(fsp);
409 if (offset + len > fsp->data_len) {
410 /* this should never happen */
411 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
412 fc_frame_crc_check(fp))
414 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
415 "data_len %x\n", len, offset, fsp->data_len);
416 fc_fcp_retry_cmd(fsp);
419 if (offset != fsp->xfer_len)
420 fsp->state |= FC_SRB_DISCONTIG;
422 sg = scsi_sglist(sc);
423 nents = scsi_sg_count(sc);
425 if (!(fr_flags(fp) & FCPHF_CRC_UNCHECKED)) {
426 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
427 &offset, KM_SOFTIRQ0, NULL);
429 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
430 copy_len = fc_copy_buffer_to_sglist(buf, len, sg, &nents,
431 &offset, KM_SOFTIRQ0, &crc);
432 buf = fc_frame_payload_get(fp, 0);
434 crc = crc32(crc, buf + len, 4 - (len % 4));
436 if (~crc != le32_to_cpu(fr_crc(fp))) {
438 stats = fc_lport_get_stats(lport);
439 stats->ErrorFrames++;
440 /* FIXME - per cpu count, not total count! */
441 if (stats->InvalidCRCCount++ < 5)
442 printk(KERN_WARNING "libfc: CRC error on data "
443 "frame for port (%6x)\n",
444 fc_host_port_id(lport->host));
446 * Assume the frame is total garbage.
447 * We may have copied it over the good part
449 * If so, we need to retry the entire operation.
450 * Otherwise, ignore it.
452 if (fsp->state & FC_SRB_DISCONTIG)
453 fc_fcp_retry_cmd(fsp);
458 if (fsp->xfer_contig_end == start_offset)
459 fsp->xfer_contig_end += copy_len;
460 fsp->xfer_len += copy_len;
463 * In the very rare event that this data arrived after the response
464 * and completes the transfer, call the completion handler.
466 if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
467 fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
468 fc_fcp_complete_locked(fsp);
472 * fc_fcp_send_data() - Send SCSI data to a target
473 * @fsp: The FCP packet the data is on
474 * @sp: The sequence the data is to be sent on
475 * @offset: The starting offset for this data request
476 * @seq_blen: The burst length for this data request
478 * Called after receiving a Transfer Ready data descriptor.
479 * If the LLD is capable of sequence offload then send down the
480 * seq_blen ammount of data in single frame, otherwise send
481 * multiple frames of the maximum frame payload supported by
484 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
485 size_t offset, size_t seq_blen)
488 struct scsi_cmnd *sc;
489 struct scatterlist *sg;
490 struct fc_frame *fp = NULL;
491 struct fc_lport *lport = fsp->lp;
496 size_t frame_offset, fh_parm_offset;
500 int using_sg = lport->sg_supp;
503 WARN_ON(seq_blen <= 0);
504 if (unlikely(offset + seq_blen > fsp->data_len)) {
505 /* this should never happen */
506 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
507 "offset %zx\n", seq_blen, offset);
508 fc_fcp_send_abort(fsp);
510 } else if (offset != fsp->xfer_len) {
511 /* Out of Order Data Request - no problem, but unexpected. */
512 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
513 "seq_blen %zx offset %zx\n", seq_blen, offset);
517 * if LLD is capable of seq_offload then set transport
518 * burst length (t_blen) to seq_blen, otherwise set t_blen
519 * to max FC frame payload previously set in fsp->max_payload.
521 t_blen = fsp->max_payload;
522 if (lport->seq_offload) {
523 t_blen = min(seq_blen, (size_t)lport->lso_max);
524 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
525 fsp, seq_blen, lport->lso_max, t_blen);
528 WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
530 t_blen &= ~(512 - 1); /* round down to block size */
531 WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD); /* won't go below 256 */
534 remaining = seq_blen;
535 fh_parm_offset = frame_offset = offset;
537 seq = lport->tt.seq_start_next(seq);
538 f_ctl = FC_FC_REL_OFF;
541 sg = scsi_sglist(sc);
543 while (remaining > 0 && sg) {
544 if (offset >= sg->length) {
545 offset -= sg->length;
550 tlen = min(t_blen, remaining);
553 * TODO. Temporary workaround. fc_seq_send() can't
554 * handle odd lengths in non-linear skbs.
555 * This will be the final fragment only.
559 fp = fc_frame_alloc(lport, using_sg ? 0 : tlen);
563 data = fc_frame_header_get(fp) + 1;
564 fh_parm_offset = frame_offset;
565 fr_max_payload(fp) = fsp->max_payload;
567 sg_bytes = min(tlen, sg->length - offset);
569 get_page(sg_page(sg));
570 skb_fill_page_desc(fp_skb(fp),
571 skb_shinfo(fp_skb(fp))->nr_frags,
572 sg_page(sg), sg->offset + offset,
574 fp_skb(fp)->data_len += sg_bytes;
575 fr_len(fp) += sg_bytes;
576 fp_skb(fp)->truesize += PAGE_SIZE;
578 size_t off = offset + sg->offset;
581 * The scatterlist item may be bigger than PAGE_SIZE,
582 * but we must not cross pages inside the kmap.
584 sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
585 (off & ~PAGE_MASK)));
586 page_addr = kmap_atomic(sg_page(sg) +
589 memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
591 kunmap_atomic(page_addr, KM_SOFTIRQ0);
595 frame_offset += sg_bytes;
597 remaining -= sg_bytes;
599 if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
604 * Send sequence with transfer sequence initiative in case
605 * this is last FCP frame of the sequence.
608 f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
610 ep = fc_seq_exch(seq);
611 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
612 FC_TYPE_FCP, f_ctl, fh_parm_offset);
615 * send fragment using for a sequence.
617 error = lport->tt.seq_send(lport, seq, fp);
619 WARN_ON(1); /* send error should be rare */
620 fc_fcp_retry_cmd(fsp);
625 fsp->xfer_len += seq_blen; /* premature count? */
630 * fc_fcp_abts_resp() - Send an ABTS response
631 * @fsp: The FCP packet that is being aborted
632 * @fp: The response frame
634 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
637 struct fc_ba_rjt *brp;
638 struct fc_frame_header *fh;
640 fh = fc_frame_header_get(fp);
641 switch (fh->fh_r_ctl) {
645 brp = fc_frame_payload_get(fp, sizeof(*brp));
646 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
651 * we will let the command timeout
652 * and scsi-ml recover in this case,
653 * therefore cleared the ba_done flag.
659 fsp->state |= FC_SRB_ABORTED;
660 fsp->state &= ~FC_SRB_ABORT_PENDING;
662 if (fsp->wait_for_comp)
663 complete(&fsp->tm_done);
665 fc_fcp_complete_locked(fsp);
670 * fc_fcp_recv() - Reveive an FCP frame
671 * @seq: The sequence the frame is on
672 * @fp: The received frame
673 * @arg: The related FCP packet
675 * Context: Called from Soft IRQ context. Can not be called
676 * holding the FCP packet list lock.
678 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
680 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
681 struct fc_lport *lport = fsp->lp;
682 struct fc_frame_header *fh;
683 struct fcp_txrdy *dd;
688 fc_fcp_error(fsp, fp);
692 fh = fc_frame_header_get(fp);
693 r_ctl = fh->fh_r_ctl;
695 if (!(lport->state & LPORT_ST_READY))
697 if (fc_fcp_lock_pkt(fsp))
699 fsp->last_pkt_time = jiffies;
701 if (fh->fh_type == FC_TYPE_BLS) {
702 fc_fcp_abts_resp(fsp, fp);
706 if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
709 if (r_ctl == FC_RCTL_DD_DATA_DESC) {
711 * received XFER RDY from the target
712 * need to send data to the target
714 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
715 dd = fc_frame_payload_get(fp, sizeof(*dd));
718 rc = fc_fcp_send_data(fsp, seq,
719 (size_t) ntohl(dd->ft_data_ro),
720 (size_t) ntohl(dd->ft_burst_len));
722 seq->rec_data = fsp->xfer_len;
723 else if (rc == -ENOMEM)
724 fsp->state |= FC_SRB_NOMEM;
725 } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
727 * received a DATA frame
728 * next we will copy the data to the system buffer
730 WARN_ON(fr_len(fp) < sizeof(*fh)); /* len may be 0 */
731 fc_fcp_recv_data(fsp, fp);
732 seq->rec_data = fsp->xfer_contig_end;
733 } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
734 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
736 fc_fcp_resp(fsp, fp);
738 FC_FCP_DBG(fsp, "unexpected frame. r_ctl %x\n", r_ctl);
741 fc_fcp_unlock_pkt(fsp);
747 * fc_fcp_resp() - Handler for FCP responses
748 * @fsp: The FCP packet the response is for
749 * @fp: The response frame
751 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
753 struct fc_frame_header *fh;
754 struct fcp_resp *fc_rp;
755 struct fcp_resp_ext *rp_ex;
756 struct fcp_resp_rsp_info *fc_rp_info;
764 fh = (struct fc_frame_header *)fr_hdr(fp);
765 if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
768 fc_rp = (struct fcp_resp *)(fh + 1);
769 fsp->cdb_status = fc_rp->fr_status;
770 flags = fc_rp->fr_flags;
771 fsp->scsi_comp_flags = flags;
772 expected_len = fsp->data_len;
774 /* if ddp, update xfer len */
775 fc_fcp_ddp_done(fsp);
777 if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
778 rp_ex = (void *)(fc_rp + 1);
779 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
780 if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
782 fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
783 if (flags & FCP_RSP_LEN_VAL) {
784 respl = ntohl(rp_ex->fr_rsp_len);
785 if (respl != sizeof(*fc_rp_info))
787 if (fsp->wait_for_comp) {
788 /* Abuse cdb_status for rsp code */
789 fsp->cdb_status = fc_rp_info->rsp_code;
790 complete(&fsp->tm_done);
792 * tmfs will not have any scsi cmd so
799 if (flags & FCP_SNS_LEN_VAL) {
800 snsl = ntohl(rp_ex->fr_sns_len);
801 if (snsl > SCSI_SENSE_BUFFERSIZE)
802 snsl = SCSI_SENSE_BUFFERSIZE;
803 memcpy(fsp->cmd->sense_buffer,
804 (char *)fc_rp_info + respl, snsl);
807 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
808 if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
810 if (flags & FCP_RESID_UNDER) {
811 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
813 * The cmnd->underflow is the minimum number of
814 * bytes that must be transfered for this
815 * command. Provided a sense condition is not
816 * present, make sure the actual amount
817 * transferred is at least the underflow value
820 if (!(flags & FCP_SNS_LEN_VAL) &&
821 (fc_rp->fr_status == 0) &&
822 (scsi_bufflen(fsp->cmd) -
823 fsp->scsi_resid) < fsp->cmd->underflow)
825 expected_len -= fsp->scsi_resid;
827 fsp->status_code = FC_ERROR;
831 fsp->state |= FC_SRB_RCV_STATUS;
834 * Check for missing or extra data frames.
836 if (unlikely(fsp->xfer_len != expected_len)) {
837 if (fsp->xfer_len < expected_len) {
839 * Some data may be queued locally,
840 * Wait a at least one jiffy to see if it is delivered.
841 * If this expires without data, we may do SRR.
843 fc_fcp_timer_set(fsp, 2);
846 fsp->status_code = FC_DATA_OVRRUN;
847 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
848 "len %x, data len %x\n",
850 fsp->xfer_len, expected_len, fsp->data_len);
852 fc_fcp_complete_locked(fsp);
856 FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
857 "snsl %u\n", flags, fr_len(fp), respl, snsl);
859 fsp->status_code = FC_ERROR;
860 fc_fcp_complete_locked(fsp);
864 * fc_fcp_complete_locked() - Complete processing of a fcp_pkt with the
866 * @fsp: The FCP packet to be completed
868 * This function may sleep if a timer is pending. The packet lock must be
869 * held, and the host lock must not be held.
871 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
873 struct fc_lport *lport = fsp->lp;
878 if (fsp->state & FC_SRB_ABORT_PENDING)
881 if (fsp->state & FC_SRB_ABORTED) {
882 if (!fsp->status_code)
883 fsp->status_code = FC_CMD_ABORTED;
886 * Test for transport underrun, independent of response
889 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
890 (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
891 fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
892 fsp->status_code = FC_DATA_UNDRUN;
900 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
901 struct fc_frame *conf_frame;
904 csp = lport->tt.seq_start_next(seq);
905 conf_frame = fc_fcp_frame_alloc(fsp->lp, 0);
907 f_ctl = FC_FC_SEQ_INIT;
908 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
909 ep = fc_seq_exch(seq);
910 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
912 FC_TYPE_FCP, f_ctl, 0);
913 lport->tt.seq_send(lport, csp, conf_frame);
916 lport->tt.exch_done(seq);
922 * fc_fcp_cleanup_cmd() - Cancel the active exchange on a fcp_pkt
923 * @fsp: The FCP packet whose exchanges should be canceled
924 * @error: The reason for the cancellation
926 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
928 struct fc_lport *lport = fsp->lp;
931 lport->tt.exch_done(fsp->seq_ptr);
934 fsp->status_code = error;
938 * fc_fcp_cleanup_each_cmd() - Cancel all exchanges on a local port
939 * @lport: The local port whose exchanges should be canceled
940 * @id: The target's ID
942 * @error: The reason for cancellation
944 * If lun or id is -1, they are ignored.
946 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lport, unsigned int id,
947 unsigned int lun, int error)
949 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
950 struct fc_fcp_pkt *fsp;
951 struct scsi_cmnd *sc_cmd;
954 spin_lock_irqsave(lport->host->host_lock, flags);
956 list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
958 if (id != -1 && scmd_id(sc_cmd) != id)
961 if (lun != -1 && sc_cmd->device->lun != lun)
964 fc_fcp_pkt_hold(fsp);
965 spin_unlock_irqrestore(lport->host->host_lock, flags);
967 if (!fc_fcp_lock_pkt(fsp)) {
968 fc_fcp_cleanup_cmd(fsp, error);
970 fc_fcp_unlock_pkt(fsp);
973 fc_fcp_pkt_release(fsp);
974 spin_lock_irqsave(lport->host->host_lock, flags);
976 * while we dropped the lock multiple pkts could
977 * have been released, so we have to start over.
981 spin_unlock_irqrestore(lport->host->host_lock, flags);
985 * fc_fcp_abort_io() - Abort all FCP-SCSI exchanges on a local port
986 * @lport: The local port whose exchanges are to be aborted
988 static void fc_fcp_abort_io(struct fc_lport *lport)
990 fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_HRD_ERROR);
994 * fc_fcp_pkt_send() - Send a fcp_pkt
995 * @lport: The local port to send the FCP packet on
996 * @fsp: The FCP packet to send
998 * Return: Zero for success and -1 for failure
999 * Locks: Called with the host lock and irqs disabled.
1001 static int fc_fcp_pkt_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp)
1003 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
1006 fsp->cmd->SCp.ptr = (char *)fsp;
1007 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1008 fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1010 int_to_scsilun(fsp->cmd->device->lun,
1011 (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1012 memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1013 list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1015 spin_unlock_irq(lport->host->host_lock);
1016 rc = lport->tt.fcp_cmd_send(lport, fsp, fc_fcp_recv);
1017 spin_lock_irq(lport->host->host_lock);
1019 list_del(&fsp->list);
1025 * fc_fcp_cmd_send() - Send a FCP command
1026 * @lport: The local port to send the command on
1027 * @fsp: The FCP packet the command is on
1028 * @resp: The handler for the response
1030 static int fc_fcp_cmd_send(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1031 void (*resp)(struct fc_seq *,
1032 struct fc_frame *fp,
1035 struct fc_frame *fp;
1037 struct fc_rport *rport;
1038 struct fc_rport_libfc_priv *rpriv;
1039 const size_t len = sizeof(fsp->cdb_cmd);
1042 if (fc_fcp_lock_pkt(fsp))
1045 fp = fc_fcp_frame_alloc(lport, sizeof(fsp->cdb_cmd));
1051 memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1054 fsp->max_payload = rport->maxframe_size;
1055 rpriv = rport->dd_data;
1057 fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1058 fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP,
1059 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1061 seq = lport->tt.exch_seq_send(lport, fp, resp, fc_fcp_pkt_destroy,
1067 fsp->last_pkt_time = jiffies;
1069 fc_fcp_pkt_hold(fsp); /* hold for fc_fcp_pkt_destroy */
1071 setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1072 fc_fcp_timer_set(fsp,
1073 (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1074 FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1076 fc_fcp_unlock_pkt(fsp);
1081 * fc_fcp_error() - Handler for FCP layer errors
1082 * @fsp: The FCP packet the error is on
1083 * @fp: The frame that has errored
1085 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1087 int error = PTR_ERR(fp);
1089 if (fc_fcp_lock_pkt(fsp))
1092 if (error == -FC_EX_CLOSED) {
1093 fc_fcp_retry_cmd(fsp);
1098 * clear abort pending, because the lower layer
1099 * decided to force completion.
1101 fsp->state &= ~FC_SRB_ABORT_PENDING;
1102 fsp->status_code = FC_CMD_PLOGO;
1103 fc_fcp_complete_locked(fsp);
1105 fc_fcp_unlock_pkt(fsp);
1109 * fc_fcp_pkt_abort() - Abort a fcp_pkt
1110 * @fsp: The FCP packet to abort on
1112 * Called to send an abort and then wait for abort completion
1114 static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1118 if (fc_fcp_send_abort(fsp))
1121 init_completion(&fsp->tm_done);
1122 fsp->wait_for_comp = 1;
1124 spin_unlock_bh(&fsp->scsi_pkt_lock);
1125 rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1126 spin_lock_bh(&fsp->scsi_pkt_lock);
1127 fsp->wait_for_comp = 0;
1130 FC_FCP_DBG(fsp, "target abort cmd failed\n");
1132 } else if (fsp->state & FC_SRB_ABORTED) {
1133 FC_FCP_DBG(fsp, "target abort cmd passed\n");
1135 fc_fcp_complete_locked(fsp);
1142 * fc_lun_reset_send() - Send LUN reset command
1143 * @data: The FCP packet that identifies the LUN to be reset
1145 static void fc_lun_reset_send(unsigned long data)
1147 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1148 struct fc_lport *lport = fsp->lp;
1149 if (lport->tt.fcp_cmd_send(lport, fsp, fc_tm_done)) {
1150 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1152 if (fc_fcp_lock_pkt(fsp))
1154 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1155 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1156 fc_fcp_unlock_pkt(fsp);
1161 * fc_lun_reset() - Send a LUN RESET command to a device
1162 * and wait for the reply
1163 * @lport: The local port to sent the comand on
1164 * @fsp: The FCP packet that identifies the LUN to be reset
1165 * @id: The SCSI command ID
1166 * @lun: The LUN ID to be reset
1168 static int fc_lun_reset(struct fc_lport *lport, struct fc_fcp_pkt *fsp,
1169 unsigned int id, unsigned int lun)
1173 fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1174 fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1175 int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1177 fsp->wait_for_comp = 1;
1178 init_completion(&fsp->tm_done);
1180 fc_lun_reset_send((unsigned long)fsp);
1183 * wait for completion of reset
1184 * after that make sure all commands are terminated
1186 rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1188 spin_lock_bh(&fsp->scsi_pkt_lock);
1189 fsp->state |= FC_SRB_COMPL;
1190 spin_unlock_bh(&fsp->scsi_pkt_lock);
1192 del_timer_sync(&fsp->timer);
1194 spin_lock_bh(&fsp->scsi_pkt_lock);
1196 lport->tt.exch_done(fsp->seq_ptr);
1197 fsp->seq_ptr = NULL;
1199 fsp->wait_for_comp = 0;
1200 spin_unlock_bh(&fsp->scsi_pkt_lock);
1203 FC_SCSI_DBG(lport, "lun reset failed\n");
1207 /* cdb_status holds the tmf's rsp code */
1208 if (fsp->cdb_status != FCP_TMF_CMPL)
1211 FC_SCSI_DBG(lport, "lun reset to lun %u completed\n", lun);
1212 fc_fcp_cleanup_each_cmd(lport, id, lun, FC_CMD_ABORTED);
1217 * fc_tm_done() - Task Managment response handler
1218 * @seq: The sequence that the response is on
1219 * @fp: The response frame
1220 * @arg: The FCP packet the response is for
1222 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1224 struct fc_fcp_pkt *fsp = arg;
1225 struct fc_frame_header *fh;
1229 * If there is an error just let it timeout or wait
1230 * for TMF to be aborted if it timedout.
1232 * scsi-eh will escalate for when either happens.
1237 if (fc_fcp_lock_pkt(fsp))
1241 * raced with eh timeout handler.
1243 if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1244 spin_unlock_bh(&fsp->scsi_pkt_lock);
1248 fh = fc_frame_header_get(fp);
1249 if (fh->fh_type != FC_TYPE_BLS)
1250 fc_fcp_resp(fsp, fp);
1251 fsp->seq_ptr = NULL;
1252 fsp->lp->tt.exch_done(seq);
1254 fc_fcp_unlock_pkt(fsp);
1258 * fc_fcp_cleanup() - Cleanup all FCP exchanges on a local port
1259 * @lport: The local port to be cleaned up
1261 static void fc_fcp_cleanup(struct fc_lport *lport)
1263 fc_fcp_cleanup_each_cmd(lport, -1, -1, FC_ERROR);
1267 * fc_fcp_timeout() - Handler for fcp_pkt timeouts
1268 * @data: The FCP packet that has timed out
1270 * If REC is supported then just issue it and return. The REC exchange will
1271 * complete or time out and recovery can continue at that point. Otherwise,
1272 * if the response has been received without all the data it has been
1273 * ER_TIMEOUT since the response was received. If the response has not been
1274 * received we see if data was received recently. If it has been then we
1275 * continue waiting, otherwise, we abort the command.
1277 static void fc_fcp_timeout(unsigned long data)
1279 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1280 struct fc_rport *rport = fsp->rport;
1281 struct fc_rport_libfc_priv *rpriv = rport->dd_data;
1283 if (fc_fcp_lock_pkt(fsp))
1286 if (fsp->cdb_cmd.fc_tm_flags)
1289 fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1291 if (rpriv->flags & FC_RP_FLAGS_REC_SUPPORTED)
1293 else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1295 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1296 else if (fsp->state & FC_SRB_RCV_STATUS)
1297 fc_fcp_complete_locked(fsp);
1299 fc_timeout_error(fsp);
1300 fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1302 fc_fcp_unlock_pkt(fsp);
1306 * fc_fcp_rec() - Send a REC ELS request
1307 * @fsp: The FCP packet to send the REC request on
1309 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1311 struct fc_lport *lport;
1312 struct fc_frame *fp;
1313 struct fc_rport *rport;
1314 struct fc_rport_libfc_priv *rpriv;
1318 rpriv = rport->dd_data;
1319 if (!fsp->seq_ptr || rpriv->rp_state != RPORT_ST_READY) {
1320 fsp->status_code = FC_HRD_ERROR;
1322 fc_fcp_complete_locked(fsp);
1325 fp = fc_fcp_frame_alloc(lport, sizeof(struct fc_els_rec));
1329 fr_seq(fp) = fsp->seq_ptr;
1330 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1331 fc_host_port_id(rpriv->local_port->host), FC_TYPE_ELS,
1332 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1333 if (lport->tt.elsct_send(lport, rport->port_id, fp, ELS_REC,
1334 fc_fcp_rec_resp, fsp,
1335 jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1336 fc_fcp_pkt_hold(fsp); /* hold while REC outstanding */
1340 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1341 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1343 fc_timeout_error(fsp);
1347 * fc_fcp_rec_resp() - Handler for REC ELS responses
1348 * @seq: The sequence the response is on
1349 * @fp: The response frame
1350 * @arg: The FCP packet the response is on
1352 * If the response is a reject then the scsi layer will handle
1353 * the timeout. If the response is a LS_ACC then if the I/O was not completed
1354 * set the timeout and return. If the I/O was completed then complete the
1355 * exchange and tell the SCSI layer.
1357 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1359 struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1360 struct fc_els_rec_acc *recp;
1361 struct fc_els_ls_rjt *rjt;
1365 enum dma_data_direction data_dir;
1367 struct fc_rport_libfc_priv *rpriv;
1370 fc_fcp_rec_error(fsp, fp);
1374 if (fc_fcp_lock_pkt(fsp))
1377 fsp->recov_retry = 0;
1378 opcode = fc_frame_payload_op(fp);
1379 if (opcode == ELS_LS_RJT) {
1380 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1381 switch (rjt->er_reason) {
1383 FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1384 "reason %d expl %d\n",
1385 fsp->rport->port_id, rjt->er_reason,
1389 FC_FCP_DBG(fsp, "device does not support REC\n");
1390 rpriv = fsp->rport->dd_data;
1392 * if we do not spport RECs or got some bogus
1393 * reason then resetup timer so we check for
1396 rpriv->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1397 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1402 * If no data transfer, the command frame got dropped
1403 * so we just retry. If data was transferred, we
1404 * lost the response but the target has no record,
1405 * so we abort and retry.
1407 if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1408 fsp->xfer_len == 0) {
1409 fc_fcp_retry_cmd(fsp);
1412 fc_timeout_error(fsp);
1415 } else if (opcode == ELS_LS_ACC) {
1416 if (fsp->state & FC_SRB_ABORTED)
1419 data_dir = fsp->cmd->sc_data_direction;
1420 recp = fc_frame_payload_get(fp, sizeof(*recp));
1421 offset = ntohl(recp->reca_fc4value);
1422 e_stat = ntohl(recp->reca_e_stat);
1424 if (e_stat & ESB_ST_COMPLETE) {
1427 * The exchange is complete.
1429 * For output, we must've lost the response.
1430 * For input, all data must've been sent.
1431 * We lost may have lost the response
1432 * (and a confirmation was requested) and maybe
1435 * If all data received, send SRR
1436 * asking for response. If partial data received,
1437 * or gaps, SRR requests data at start of gap.
1438 * Recovery via SRR relies on in-order-delivery.
1440 if (data_dir == DMA_TO_DEVICE) {
1441 r_ctl = FC_RCTL_DD_CMD_STATUS;
1442 } else if (fsp->xfer_contig_end == offset) {
1443 r_ctl = FC_RCTL_DD_CMD_STATUS;
1445 offset = fsp->xfer_contig_end;
1446 r_ctl = FC_RCTL_DD_SOL_DATA;
1448 fc_fcp_srr(fsp, r_ctl, offset);
1449 } else if (e_stat & ESB_ST_SEQ_INIT) {
1452 * The remote port has the initiative, so just
1453 * keep waiting for it to complete.
1455 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1459 * The exchange is incomplete, we have seq. initiative.
1460 * Lost response with requested confirmation,
1461 * lost confirmation, lost transfer ready or
1464 * For output, if not all data was received, ask
1465 * for transfer ready to be repeated.
1467 * If we received or sent all the data, send SRR to
1470 * If we lost a response, we may have lost some read
1473 r_ctl = FC_RCTL_DD_SOL_DATA;
1474 if (data_dir == DMA_TO_DEVICE) {
1475 r_ctl = FC_RCTL_DD_CMD_STATUS;
1476 if (offset < fsp->data_len)
1477 r_ctl = FC_RCTL_DD_DATA_DESC;
1478 } else if (offset == fsp->xfer_contig_end) {
1479 r_ctl = FC_RCTL_DD_CMD_STATUS;
1480 } else if (fsp->xfer_contig_end < offset) {
1481 offset = fsp->xfer_contig_end;
1483 fc_fcp_srr(fsp, r_ctl, offset);
1487 fc_fcp_unlock_pkt(fsp);
1489 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1494 * fc_fcp_rec_error() - Handler for REC errors
1495 * @fsp: The FCP packet the error is on
1496 * @fp: The REC frame
1498 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1500 int error = PTR_ERR(fp);
1502 if (fc_fcp_lock_pkt(fsp))
1507 fc_fcp_retry_cmd(fsp);
1511 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1512 fsp, fsp->rport->port_id, error);
1513 fsp->status_code = FC_CMD_PLOGO;
1516 case -FC_EX_TIMEOUT:
1518 * Assume REC or LS_ACC was lost.
1519 * The exchange manager will have aborted REC, so retry.
1521 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1522 fsp->rport->port_id, error, fsp->recov_retry,
1523 FC_MAX_RECOV_RETRY);
1524 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1527 fc_timeout_error(fsp);
1530 fc_fcp_unlock_pkt(fsp);
1532 fc_fcp_pkt_release(fsp); /* drop hold for outstanding REC */
1536 * fc_timeout_error() - Handler for fcp_pkt timeouts
1537 * @fsp: The FCP packt that has timed out
1539 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1541 fsp->status_code = FC_CMD_TIME_OUT;
1542 fsp->cdb_status = 0;
1545 * if this fails then we let the scsi command timer fire and
1548 fc_fcp_send_abort(fsp);
1552 * fc_fcp_srr() - Send a SRR request (Sequence Retransmission Request)
1553 * @fsp: The FCP packet the SRR is to be sent on
1554 * @r_ctl: The R_CTL field for the SRR request
1555 * This is called after receiving status but insufficient data, or
1556 * when expecting status but the request has timed out.
1558 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1560 struct fc_lport *lport = fsp->lp;
1561 struct fc_rport *rport;
1562 struct fc_rport_libfc_priv *rpriv;
1563 struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1565 struct fcp_srr *srr;
1566 struct fc_frame *fp;
1570 rpriv = rport->dd_data;
1571 cdb_op = fsp->cdb_cmd.fc_cdb[0];
1573 if (!(rpriv->flags & FC_RP_FLAGS_RETRY) ||
1574 rpriv->rp_state != RPORT_ST_READY)
1575 goto retry; /* shouldn't happen */
1576 fp = fc_fcp_frame_alloc(lport, sizeof(*srr));
1580 srr = fc_frame_payload_get(fp, sizeof(*srr));
1581 memset(srr, 0, sizeof(*srr));
1582 srr->srr_op = ELS_SRR;
1583 srr->srr_ox_id = htons(ep->oxid);
1584 srr->srr_rx_id = htons(ep->rxid);
1585 srr->srr_r_ctl = r_ctl;
1586 srr->srr_rel_off = htonl(offset);
1588 fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1589 fc_host_port_id(rpriv->local_port->host), FC_TYPE_FCP,
1590 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1592 seq = lport->tt.exch_seq_send(lport, fp, fc_fcp_srr_resp, NULL,
1593 fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1597 fsp->recov_seq = seq;
1598 fsp->xfer_len = offset;
1599 fsp->xfer_contig_end = offset;
1600 fsp->state &= ~FC_SRB_RCV_STATUS;
1601 fc_fcp_pkt_hold(fsp); /* hold for outstanding SRR */
1604 fc_fcp_retry_cmd(fsp);
1608 * fc_fcp_srr_resp() - Handler for SRR response
1609 * @seq: The sequence the SRR is on
1610 * @fp: The SRR frame
1611 * @arg: The FCP packet the SRR is on
1613 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1615 struct fc_fcp_pkt *fsp = arg;
1616 struct fc_frame_header *fh;
1619 fc_fcp_srr_error(fsp, fp);
1623 if (fc_fcp_lock_pkt(fsp))
1626 fh = fc_frame_header_get(fp);
1628 * BUG? fc_fcp_srr_error calls exch_done which would release
1629 * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1630 * then fc_exch_timeout would be sending an abort. The exch_done
1631 * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1632 * an abort response though.
1634 if (fh->fh_type == FC_TYPE_BLS) {
1635 fc_fcp_unlock_pkt(fsp);
1639 fsp->recov_seq = NULL;
1640 switch (fc_frame_payload_op(fp)) {
1642 fsp->recov_retry = 0;
1643 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1647 fc_timeout_error(fsp);
1650 fc_fcp_unlock_pkt(fsp);
1651 fsp->lp->tt.exch_done(seq);
1654 fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */
1658 * fc_fcp_srr_error() - Handler for SRR errors
1659 * @fsp: The FCP packet that the SRR error is on
1660 * @fp: The SRR frame
1662 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1664 if (fc_fcp_lock_pkt(fsp))
1666 fsp->lp->tt.exch_done(fsp->recov_seq);
1667 fsp->recov_seq = NULL;
1668 switch (PTR_ERR(fp)) {
1669 case -FC_EX_TIMEOUT:
1670 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1673 fc_timeout_error(fsp);
1675 case -FC_EX_CLOSED: /* e.g., link failure */
1678 fc_fcp_retry_cmd(fsp);
1681 fc_fcp_unlock_pkt(fsp);
1683 fc_fcp_pkt_release(fsp); /* drop hold for outstanding SRR */
1687 * fc_fcp_lport_queue_ready() - Determine if the lport and it's queue is ready
1688 * @lport: The local port to be checked
1690 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lport)
1693 return (lport->state == LPORT_ST_READY) &&
1694 lport->link_up && !lport->qfull;
1698 * fc_queuecommand() - The queuecommand function of the SCSI template
1699 * @cmd: The scsi_cmnd to be executed
1700 * @done: The callback function to be called when the scsi_cmnd is complete
1702 * This is the i/o strategy routine, called by the SCSI layer. This routine
1703 * is called with the host_lock held.
1705 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1707 struct fc_lport *lport;
1708 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1709 struct fc_fcp_pkt *fsp;
1710 struct fc_rport_libfc_priv *rpriv;
1713 struct fcoe_dev_stats *stats;
1715 lport = shost_priv(sc_cmd->device->host);
1717 rval = fc_remote_port_chkready(rport);
1719 sc_cmd->result = rval;
1724 if (!*(struct fc_remote_port **)rport->dd_data) {
1726 * rport is transitioning from blocked/deleted to
1729 sc_cmd->result = DID_IMM_RETRY << 16;
1734 rpriv = rport->dd_data;
1736 if (!fc_fcp_lport_queue_ready(lport)) {
1737 rc = SCSI_MLQUEUE_HOST_BUSY;
1741 fsp = fc_fcp_pkt_alloc(lport, GFP_ATOMIC);
1743 rc = SCSI_MLQUEUE_HOST_BUSY;
1748 * build the libfc request pkt
1750 fsp->cmd = sc_cmd; /* save the cmd */
1751 fsp->lp = lport; /* save the softc ptr */
1752 fsp->rport = rport; /* set the remote port ptr */
1753 fsp->xfer_ddp = FC_XID_UNKNOWN;
1754 sc_cmd->scsi_done = done;
1757 * set up the transfer length
1759 fsp->data_len = scsi_bufflen(sc_cmd);
1763 * setup the data direction
1765 stats = fc_lport_get_stats(lport);
1766 if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1767 fsp->req_flags = FC_SRB_READ;
1768 stats->InputRequests++;
1769 stats->InputMegabytes = fsp->data_len;
1770 } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1771 fsp->req_flags = FC_SRB_WRITE;
1772 stats->OutputRequests++;
1773 stats->OutputMegabytes = fsp->data_len;
1776 stats->ControlRequests++;
1779 fsp->tgt_flags = rpriv->flags;
1781 init_timer(&fsp->timer);
1782 fsp->timer.data = (unsigned long)fsp;
1785 * send it to the lower layer
1786 * if we get -1 return then put the request in the pending
1789 rval = fc_fcp_pkt_send(lport, fsp);
1791 fsp->state = FC_SRB_FREE;
1792 fc_fcp_pkt_release(fsp);
1793 rc = SCSI_MLQUEUE_HOST_BUSY;
1798 EXPORT_SYMBOL(fc_queuecommand);
1801 * fc_io_compl() - Handle responses for completed commands
1802 * @fsp: The FCP packet that is complete
1804 * Translates fcp_pkt errors to a Linux SCSI errors.
1805 * The fcp packet lock must be held when calling.
1807 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1809 struct fc_fcp_internal *si;
1810 struct scsi_cmnd *sc_cmd;
1811 struct fc_lport *lport;
1812 unsigned long flags;
1814 /* release outstanding ddp context */
1815 fc_fcp_ddp_done(fsp);
1817 fsp->state |= FC_SRB_COMPL;
1818 if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1819 spin_unlock_bh(&fsp->scsi_pkt_lock);
1820 del_timer_sync(&fsp->timer);
1821 spin_lock_bh(&fsp->scsi_pkt_lock);
1825 si = fc_get_scsi_internal(lport);
1826 spin_lock_irqsave(lport->host->host_lock, flags);
1828 spin_unlock_irqrestore(lport->host->host_lock, flags);
1833 * if a command timed out while we had to try and throttle IO
1834 * and it is now getting cleaned up, then we are about to
1835 * try again so clear the throttled flag incase we get more
1838 if (si->throttled && fsp->state & FC_SRB_NOMEM)
1844 if (!sc_cmd->SCp.ptr) {
1845 spin_unlock_irqrestore(lport->host->host_lock, flags);
1849 CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1850 switch (fsp->status_code) {
1852 if (fsp->cdb_status == 0) {
1856 sc_cmd->result = DID_OK << 16;
1857 if (fsp->scsi_resid)
1858 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1861 * transport level I/O was ok but scsi
1862 * has non zero status
1864 sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1868 sc_cmd->result = DID_ERROR << 16;
1870 case FC_DATA_UNDRUN:
1871 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1873 * scsi status is good but transport level
1876 sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ?
1877 DID_OK : DID_ERROR) << 16;
1880 * scsi got underrun, this is an error
1882 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1883 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1886 case FC_DATA_OVRRUN:
1888 * overrun is an error
1890 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1892 case FC_CMD_ABORTED:
1893 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1895 case FC_CMD_TIME_OUT:
1896 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1899 sc_cmd->result = (DID_RESET << 16);
1902 sc_cmd->result = (DID_NO_CONNECT << 16);
1905 sc_cmd->result = (DID_ERROR << 16);
1909 list_del(&fsp->list);
1910 sc_cmd->SCp.ptr = NULL;
1911 sc_cmd->scsi_done(sc_cmd);
1912 spin_unlock_irqrestore(lport->host->host_lock, flags);
1914 /* release ref from initial allocation in queue command */
1915 fc_fcp_pkt_release(fsp);
1919 * fc_eh_abort() - Abort a command
1920 * @sc_cmd: The SCSI command to abort
1922 * From SCSI host template.
1923 * Send an ABTS to the target device and wait for the response.
1925 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1927 struct fc_fcp_pkt *fsp;
1928 struct fc_lport *lport;
1930 unsigned long flags;
1932 lport = shost_priv(sc_cmd->device->host);
1933 if (lport->state != LPORT_ST_READY)
1935 else if (!lport->link_up)
1938 spin_lock_irqsave(lport->host->host_lock, flags);
1939 fsp = CMD_SP(sc_cmd);
1941 /* command completed while scsi eh was setting up */
1942 spin_unlock_irqrestore(lport->host->host_lock, flags);
1945 /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1946 fc_fcp_pkt_hold(fsp);
1947 spin_unlock_irqrestore(lport->host->host_lock, flags);
1949 if (fc_fcp_lock_pkt(fsp)) {
1950 /* completed while we were waiting for timer to be deleted */
1955 rc = fc_fcp_pkt_abort(fsp);
1956 fc_fcp_unlock_pkt(fsp);
1959 fc_fcp_pkt_release(fsp);
1962 EXPORT_SYMBOL(fc_eh_abort);
1965 * fc_eh_device_reset() - Reset a single LUN
1966 * @sc_cmd: The SCSI command which identifies the device whose
1967 * LUN is to be reset
1969 * Set from SCSI host template.
1971 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1973 struct fc_lport *lport;
1974 struct fc_fcp_pkt *fsp;
1975 struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1979 rval = fc_remote_port_chkready(rport);
1983 lport = shost_priv(sc_cmd->device->host);
1985 if (lport->state != LPORT_ST_READY)
1988 FC_SCSI_DBG(lport, "Resetting rport (%6x)\n", rport->port_id);
1990 fsp = fc_fcp_pkt_alloc(lport, GFP_NOIO);
1992 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
1993 sc_cmd->result = DID_NO_CONNECT << 16;
1998 * Build the libfc request pkt. Do not set the scsi cmnd, because
1999 * the sc passed in is not setup for execution like when sent
2000 * through the queuecommand callout.
2002 fsp->lp = lport; /* save the softc ptr */
2003 fsp->rport = rport; /* set the remote port ptr */
2006 * flush outstanding commands
2008 rc = fc_lun_reset(lport, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2009 fsp->state = FC_SRB_FREE;
2010 fc_fcp_pkt_release(fsp);
2015 EXPORT_SYMBOL(fc_eh_device_reset);
2018 * fc_eh_host_reset() - Reset a Scsi_Host.
2019 * @sc_cmd: The SCSI command that identifies the SCSI host to be reset
2021 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2023 struct Scsi_Host *shost = sc_cmd->device->host;
2024 struct fc_lport *lport = shost_priv(shost);
2025 unsigned long wait_tmo;
2027 FC_SCSI_DBG(lport, "Resetting host\n");
2029 lport->tt.lport_reset(lport);
2030 wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2031 while (!fc_fcp_lport_queue_ready(lport) && time_before(jiffies,
2035 if (fc_fcp_lport_queue_ready(lport)) {
2036 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2037 "on port (%6x)\n", fc_host_port_id(lport->host));
2040 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2041 "port (%6x) is not ready.\n",
2042 fc_host_port_id(lport->host));
2046 EXPORT_SYMBOL(fc_eh_host_reset);
2049 * fc_slave_alloc() - Configure the queue depth of a Scsi_Host
2050 * @sdev: The SCSI device that identifies the SCSI host
2052 * Configures queue depth based on host's cmd_per_len. If not set
2053 * then we use the libfc default.
2055 int fc_slave_alloc(struct scsi_device *sdev)
2057 struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2059 if (!rport || fc_remote_port_chkready(rport))
2062 if (sdev->tagged_supported)
2063 scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2065 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
2066 FC_FCP_DFLT_QUEUE_DEPTH);
2070 EXPORT_SYMBOL(fc_slave_alloc);
2073 * fc_change_queue_depth() - Change a device's queue depth
2074 * @sdev: The SCSI device whose queue depth is to change
2075 * @qdepth: The new queue depth
2076 * @reason: The resason for the change
2078 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
2081 case SCSI_QDEPTH_DEFAULT:
2082 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2084 case SCSI_QDEPTH_QFULL:
2085 scsi_track_queue_full(sdev, qdepth);
2087 case SCSI_QDEPTH_RAMP_UP:
2088 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2093 return sdev->queue_depth;
2095 EXPORT_SYMBOL(fc_change_queue_depth);
2098 * fc_change_queue_type() - Change a device's queue type
2099 * @sdev: The SCSI device whose queue depth is to change
2100 * @tag_type: Identifier for queue type
2102 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2104 if (sdev->tagged_supported) {
2105 scsi_set_tag_type(sdev, tag_type);
2107 scsi_activate_tcq(sdev, sdev->queue_depth);
2109 scsi_deactivate_tcq(sdev, sdev->queue_depth);
2115 EXPORT_SYMBOL(fc_change_queue_type);
2118 * fc_fcp_destory() - Tear down the FCP layer for a given local port
2119 * @lport: The local port that no longer needs the FCP layer
2121 void fc_fcp_destroy(struct fc_lport *lport)
2123 struct fc_fcp_internal *si = fc_get_scsi_internal(lport);
2125 if (!list_empty(&si->scsi_pkt_queue))
2126 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2127 "port (%6x)\n", fc_host_port_id(lport->host));
2129 mempool_destroy(si->scsi_pkt_pool);
2131 lport->scsi_priv = NULL;
2133 EXPORT_SYMBOL(fc_fcp_destroy);
2139 scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2140 sizeof(struct fc_fcp_pkt),
2141 0, SLAB_HWCACHE_ALIGN, NULL);
2142 if (!scsi_pkt_cachep) {
2143 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2144 "module load failed!");
2151 void fc_destroy_fcp()
2153 if (scsi_pkt_cachep)
2154 kmem_cache_destroy(scsi_pkt_cachep);
2158 * fc_fcp_init() - Initialize the FCP layer for a local port
2159 * @lport: The local port to initialize the exchange layer for
2161 int fc_fcp_init(struct fc_lport *lport)
2164 struct fc_fcp_internal *si;
2166 if (!lport->tt.fcp_cmd_send)
2167 lport->tt.fcp_cmd_send = fc_fcp_cmd_send;
2169 if (!lport->tt.fcp_cleanup)
2170 lport->tt.fcp_cleanup = fc_fcp_cleanup;
2172 if (!lport->tt.fcp_abort_io)
2173 lport->tt.fcp_abort_io = fc_fcp_abort_io;
2175 si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2178 lport->scsi_priv = si;
2179 INIT_LIST_HEAD(&si->scsi_pkt_queue);
2181 si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2182 if (!si->scsi_pkt_pool) {
2192 EXPORT_SYMBOL(fc_fcp_init);