SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/scsi/libfc/fc_fcp.c

   1 /*
   2  * Copyright(c) 2007 Intel Corporation. All rights reserved.
   3  * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
   4  * Copyright(c) 2008 Mike Christie
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Maintained at www.Open-FCoE.org
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/delay.h>
  24 #include <linux/kernel.h>
  25 #include <linux/types.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/scatterlist.h>
  28 #include <linux/err.h>
  29 #include <linux/crc32.h>
  30
  31 #include <scsi/scsi_tcq.h>
  32 #include <scsi/scsi.h>
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi_device.h>
  35 #include <scsi/scsi_cmnd.h>
  36
  37 #include <scsi/fc/fc_fc2.h>
  38
  39 #include <scsi/libfc.h>
  40 #include <scsi/fc_encode.h>
  41
  42 MODULE_AUTHOR("Open-FCoE.org");
  43 MODULE_DESCRIPTION("libfc");
  44 MODULE_LICENSE("GPL");
  45
  46 static int fc_fcp_debug;
  47
  48 #define FC_DEBUG_FCP(fmt...)                    \
  49         do {                                    \
  50                 if (fc_fcp_debug)               \
  51                         FC_DBG(fmt);            \
  52         } while (0)
  53
  54 static struct kmem_cache *scsi_pkt_cachep;
  55
  56 /* SRB state definitions */
  57 #define FC_SRB_FREE             0               /* cmd is free */
  58 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
  59 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
  60 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
  61 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
  62 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
  63 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
  64 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
  65 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
  66
  67 #define FC_SRB_READ             (1 << 1)
  68 #define FC_SRB_WRITE            (1 << 0)
  69
  70 /*
  71  * The SCp.ptr should be tested and set under the host lock. NULL indicates
  72  * that the command has been retruned to the scsi layer.
  73  */
  74 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
  75 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
  76 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
  77 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
  78 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
  79
  80 struct fc_fcp_internal {
  81         mempool_t       *scsi_pkt_pool;
  82         struct list_head scsi_pkt_queue;
  83         u8              throttled;
  84 };
  85
  86 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
  87
  88 /*
  89  * function prototypes
  90  * FC scsi I/O related functions
  91  */
  92 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
  93 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
  94 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
  95 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
  96 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
  97 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
  98 static void fc_timeout_error(struct fc_fcp_pkt *);
  99 static void fc_fcp_timeout(unsigned long data);
 100 static void fc_fcp_rec(struct fc_fcp_pkt *);
 101 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
 102 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
 103 static void fc_io_compl(struct fc_fcp_pkt *);
 104
 105 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
 106 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
 107 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
 108
 109 /*
 110  * command status codes
 111  */
 112 #define FC_COMPLETE             0
 113 #define FC_CMD_ABORTED          1
 114 #define FC_CMD_RESET            2
 115 #define FC_CMD_PLOGO            3
 116 #define FC_SNS_RCV              4
 117 #define FC_TRANS_ERR            5
 118 #define FC_DATA_OVRRUN          6
 119 #define FC_DATA_UNDRUN          7
 120 #define FC_ERROR                8
 121 #define FC_HRD_ERROR            9
 122 #define FC_CMD_TIME_OUT         10
 123
 124 /*
 125  * Error recovery timeout values.
 126  */
 127 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 128 #define FC_SCSI_TM_TOV          (10 * HZ)
 129 #define FC_SCSI_REC_TOV         (2 * HZ)
 130 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 131
 132 #define FC_MAX_ERROR_CNT        5
 133 #define FC_MAX_RECOV_RETRY      3
 134
 135 #define FC_FCP_DFLT_QUEUE_DEPTH 32
 136
 137 /**
 138  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 139  * @lp:         fc lport struct
 140  * @gfp:        gfp flags for allocation
 141  *
 142  * This is used by upper layer scsi driver.
 143  * Return Value : scsi_pkt structure or null on allocation failure.
 144  * Context      : call from process context. no locking required.
 145  */
 146 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
 147 {
 148         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 149         struct fc_fcp_pkt *fsp;
 150
 151         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
 152         if (fsp) {
 153                 memset(fsp, 0, sizeof(*fsp));
 154                 fsp->lp = lp;
 155                 atomic_set(&fsp->ref_cnt, 1);
 156                 init_timer(&fsp->timer);
 157                 INIT_LIST_HEAD(&fsp->list);
 158                 spin_lock_init(&fsp->scsi_pkt_lock);
 159         }
 160         return fsp;
 161 }
 162
 163 /**
 164  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
 165  * @fsp:        fcp packet struct
 166  *
 167  * This is used by upper layer scsi driver.
 168  * Context      : call from process  and interrupt context.
 169  *                no locking required
 170  */
 171 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
 172 {
 173         if (atomic_dec_and_test(&fsp->ref_cnt)) {
 174                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
 175
 176                 mempool_free(fsp, si->scsi_pkt_pool);
 177         }
 178 }
 179
 180 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
 181 {
 182         atomic_inc(&fsp->ref_cnt);
 183 }
 184
 185 /**
 186  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
 187  * @seq:                exchange sequence
 188  * @fsp:        fcp packet struct
 189  *
 190  * Release hold on scsi_pkt packet set to keep scsi_pkt
 191  * till EM layer exch resource is not freed.
 192  * Context      : called from from EM layer.
 193  *                no locking required
 194  */
 195 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
 196 {
 197         fc_fcp_pkt_release(fsp);
 198 }
 199
 200 /**
 201  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
 202  * @fsp:        fcp packet
 203  *
 204  * We should only return error if we return a command to scsi-ml before
 205  * getting a response. This can happen in cases where we send a abort, but
 206  * do not wait for the response and the abort and command can be passing
 207  * each other on the wire/network-layer.
 208  *
 209  * Note: this function locks the packet and gets a reference to allow
 210  * callers to call the completion function while the lock is held and
 211  * not have to worry about the packets refcount.
 212  *
 213  * TODO: Maybe we should just have callers grab/release the lock and
 214  * have a function that they call to verify the fsp and grab a ref if
 215  * needed.
 216  */
 217 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
 218 {
 219         spin_lock_bh(&fsp->scsi_pkt_lock);
 220         if (fsp->state & FC_SRB_COMPL) {
 221                 spin_unlock_bh(&fsp->scsi_pkt_lock);
 222                 return -EPERM;
 223         }
 224
 225         fc_fcp_pkt_hold(fsp);
 226         return 0;
 227 }
 228
 229 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
 230 {
 231         spin_unlock_bh(&fsp->scsi_pkt_lock);
 232         fc_fcp_pkt_release(fsp);
 233 }
 234
 235 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
 236 {
 237         if (!(fsp->state & FC_SRB_COMPL))
 238                 mod_timer(&fsp->timer, jiffies + delay);
 239 }
 240
 241 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 242 {
 243         if (!fsp->seq_ptr)
 244                 return -EINVAL;
 245
 246         fsp->state |= FC_SRB_ABORT_PENDING;
 247         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 248 }
 249
 250 /*
 251  * Retry command.
 252  * An abort isn't needed.
 253  */
 254 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
 255 {
 256         if (fsp->seq_ptr) {
 257                 fsp->lp->tt.exch_done(fsp->seq_ptr);
 258                 fsp->seq_ptr = NULL;
 259         }
 260
 261         fsp->state &= ~FC_SRB_ABORT_PENDING;
 262         fsp->io_status = 0;
 263         fsp->status_code = FC_ERROR;
 264         fc_fcp_complete_locked(fsp);
 265 }
 266
 267 /*
 268  * Receive SCSI data from target.
 269  * Called after receiving solicited data.
 270  */
 271 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 272 {
 273         struct scsi_cmnd *sc = fsp->cmd;
 274         struct fc_lport *lp = fsp->lp;
 275         struct fcoe_dev_stats *stats;
 276         struct fc_frame_header *fh;
 277         size_t start_offset;
 278         size_t offset;
 279         u32 crc;
 280         u32 copy_len = 0;
 281         size_t len;
 282         void *buf;
 283         struct scatterlist *sg;
 284         size_t remaining;
 285
 286         fh = fc_frame_header_get(fp);
 287         offset = ntohl(fh->fh_parm_offset);
 288         start_offset = offset;
 289         len = fr_len(fp) - sizeof(*fh);
 290         buf = fc_frame_payload_get(fp, 0);
 291
 292         if (offset + len > fsp->data_len) {
 293                 /* this should never happen */
 294                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
 295                     fc_frame_crc_check(fp))
 296                         goto crc_err;
 297                 FC_DEBUG_FCP("data received past end. len %zx offset %zx "
 298                              "data_len %x\n", len, offset, fsp->data_len);
 299                 fc_fcp_retry_cmd(fsp);
 300                 return;
 301         }
 302         if (offset != fsp->xfer_len)
 303                 fsp->state |= FC_SRB_DISCONTIG;
 304
 305         crc = 0;
 306         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 307                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
 308
 309         sg = scsi_sglist(sc);
 310         remaining = len;
 311
 312         while (remaining > 0 && sg) {
 313                 size_t off;
 314                 void *page_addr;
 315                 size_t sg_bytes;
 316
 317                 if (offset >= sg->length) {
 318                         offset -= sg->length;
 319                         sg = sg_next(sg);
 320                         continue;
 321                 }
 322                 sg_bytes = min(remaining, sg->length - offset);
 323
 324                 /*
 325                  * The scatterlist item may be bigger than PAGE_SIZE,
 326                  * but we are limited to mapping PAGE_SIZE at a time.
 327                  */
 328                 off = offset + sg->offset;
 329                 sg_bytes = min(sg_bytes, (size_t)
 330                                (PAGE_SIZE - (off & ~PAGE_MASK)));
 331                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
 332                                         KM_SOFTIRQ0);
 333                 if (!page_addr)
 334                         break;          /* XXX panic? */
 335
 336                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 337                         crc = crc32(crc, buf, sg_bytes);
 338                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
 339                        sg_bytes);
 340
 341                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
 342                 buf += sg_bytes;
 343                 offset += sg_bytes;
 344                 remaining -= sg_bytes;
 345                 copy_len += sg_bytes;
 346         }
 347
 348         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
 349                 buf = fc_frame_payload_get(fp, 0);
 350                 if (len % 4) {
 351                         crc = crc32(crc, buf + len, 4 - (len % 4));
 352                         len += 4 - (len % 4);
 353                 }
 354
 355                 if (~crc != le32_to_cpu(fr_crc(fp))) {
 356 crc_err:
 357                         stats = lp->dev_stats[smp_processor_id()];
 358                         stats->ErrorFrames++;
 359                         if (stats->InvalidCRCCount++ < 5)
 360                                 FC_DBG("CRC error on data frame\n");
 361                         /*
 362                          * Assume the frame is total garbage.
 363                          * We may have copied it over the good part
 364                          * of the buffer.
 365                          * If so, we need to retry the entire operation.
 366                          * Otherwise, ignore it.
 367                          */
 368                         if (fsp->state & FC_SRB_DISCONTIG)
 369                                 fc_fcp_retry_cmd(fsp);
 370                         return;
 371                 }
 372         }
 373
 374         if (fsp->xfer_contig_end == start_offset)
 375                 fsp->xfer_contig_end += copy_len;
 376         fsp->xfer_len += copy_len;
 377
 378         /*
 379          * In the very rare event that this data arrived after the response
 380          * and completes the transfer, call the completion handler.
 381          */
 382         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
 383             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
 384                 fc_fcp_complete_locked(fsp);
 385 }
 386
 387 /**
 388  * fc_fcp_send_data() -  Send SCSI data to target.
 389  * @fsp: ptr to fc_fcp_pkt
 390  * @sp: ptr to this sequence
 391  * @offset: starting offset for this data request
 392  * @seq_blen: the burst length for this data request
 393  *
 394  * Called after receiving a Transfer Ready data descriptor.
 395  * if LLD is capable of seq offload then send down seq_blen
 396  * size of data in single frame, otherwise send multiple FC
 397  * frames of max FC frame payload supported by target port.
 398  *
 399  * Returns : 0 for success.
 400  */
 401 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
 402                             size_t offset, size_t seq_blen)
 403 {
 404         struct fc_exch *ep;
 405         struct scsi_cmnd *sc;
 406         struct scatterlist *sg;
 407         struct fc_frame *fp = NULL;
 408         struct fc_lport *lp = fsp->lp;
 409         size_t remaining;
 410         size_t t_blen;
 411         size_t tlen;
 412         size_t sg_bytes;
 413         size_t frame_offset, fh_parm_offset;
 414         int error;
 415         void *data = NULL;
 416         void *page_addr;
 417         int using_sg = lp->sg_supp;
 418         u32 f_ctl;
 419
 420         WARN_ON(seq_blen <= 0);
 421         if (unlikely(offset + seq_blen > fsp->data_len)) {
 422                 /* this should never happen */
 423                 FC_DEBUG_FCP("xfer-ready past end. seq_blen %zx offset %zx\n",
 424                              seq_blen, offset);
 425                 fc_fcp_send_abort(fsp);
 426                 return 0;
 427         } else if (offset != fsp->xfer_len) {
 428                 /* Out of Order Data Request - no problem, but unexpected. */
 429                 FC_DEBUG_FCP("xfer-ready non-contiguous. "
 430                              "seq_blen %zx offset %zx\n", seq_blen, offset);
 431         }
 432
 433         /*
 434          * if LLD is capable of seq_offload then set transport
 435          * burst length (t_blen) to seq_blen, otherwise set t_blen
 436          * to max FC frame payload previously set in fsp->max_payload.
 437          */
 438         t_blen = lp->seq_offload ? seq_blen : fsp->max_payload;
 439         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
 440         if (t_blen > 512)
 441                 t_blen &= ~(512 - 1);   /* round down to block size */
 442         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
 443         sc = fsp->cmd;
 444
 445         remaining = seq_blen;
 446         fh_parm_offset = frame_offset = offset;
 447         tlen = 0;
 448         seq = lp->tt.seq_start_next(seq);
 449         f_ctl = FC_FC_REL_OFF;
 450         WARN_ON(!seq);
 451
 452         /*
 453          * If a get_page()/put_page() will fail, don't use sg lists
 454          * in the fc_frame structure.
 455          *
 456          * The put_page() may be long after the I/O has completed
 457          * in the case of FCoE, since the network driver does it
 458          * via free_skb().  See the test in free_pages_check().
 459          *
 460          * Test this case with 'dd </dev/zero >/dev/st0 bs=64k'.
 461          */
 462         if (using_sg) {
 463                 for (sg = scsi_sglist(sc); sg; sg = sg_next(sg)) {
 464                         if (page_count(sg_page(sg)) == 0 ||
 465                             (sg_page(sg)->flags & (1 << PG_lru |
 466                                                    1 << PG_private |
 467                                                    1 << PG_locked |
 468                                                    1 << PG_active |
 469                                                    1 << PG_slab |
 470                                                    1 << PG_swapcache |
 471                                                    1 << PG_writeback |
 472                                                    1 << PG_reserved |
 473                                                    1 << PG_buddy))) {
 474                                 using_sg = 0;
 475                                 break;
 476                         }
 477                 }
 478         }
 479         sg = scsi_sglist(sc);
 480
 481         while (remaining > 0 && sg) {
 482                 if (offset >= sg->length) {
 483                         offset -= sg->length;
 484                         sg = sg_next(sg);
 485                         continue;
 486                 }
 487                 if (!fp) {
 488                         tlen = min(t_blen, remaining);
 489
 490                         /*
 491                          * TODO.  Temporary workaround.  fc_seq_send() can't
 492                          * handle odd lengths in non-linear skbs.
 493                          * This will be the final fragment only.
 494                          */
 495                         if (tlen % 4)
 496                                 using_sg = 0;
 497                         if (using_sg) {
 498                                 fp = _fc_frame_alloc(lp, 0);
 499                                 if (!fp)
 500                                         return -ENOMEM;
 501                         } else {
 502                                 fp = fc_frame_alloc(lp, tlen);
 503                                 if (!fp)
 504                                         return -ENOMEM;
 505
 506                                 data = (void *)(fr_hdr(fp)) +
 507                                         sizeof(struct fc_frame_header);
 508                         }
 509                         fh_parm_offset = frame_offset;
 510                         fr_max_payload(fp) = fsp->max_payload;
 511                 }
 512                 sg_bytes = min(tlen, sg->length - offset);
 513                 if (using_sg) {
 514                         WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags >
 515                                 FC_FRAME_SG_LEN);
 516                         get_page(sg_page(sg));
 517                         skb_fill_page_desc(fp_skb(fp),
 518                                            skb_shinfo(fp_skb(fp))->nr_frags,
 519                                            sg_page(sg), sg->offset + offset,
 520                                            sg_bytes);
 521                         fp_skb(fp)->data_len += sg_bytes;
 522                         fr_len(fp) += sg_bytes;
 523                         fp_skb(fp)->truesize += PAGE_SIZE;
 524                 } else {
 525                         size_t off = offset + sg->offset;
 526
 527                         /*
 528                          * The scatterlist item may be bigger than PAGE_SIZE,
 529                          * but we must not cross pages inside the kmap.
 530                          */
 531                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
 532                                                            (off & ~PAGE_MASK)));
 533                         page_addr = kmap_atomic(sg_page(sg) +
 534                                                 (off >> PAGE_SHIFT),
 535                                                 KM_SOFTIRQ0);
 536                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
 537                                sg_bytes);
 538                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
 539                         data += sg_bytes;
 540                 }
 541                 offset += sg_bytes;
 542                 frame_offset += sg_bytes;
 543                 tlen -= sg_bytes;
 544                 remaining -= sg_bytes;
 545
 546                 if (tlen)
 547                         continue;
 548
 549                 /*
 550                  * Send sequence with transfer sequence initiative in case
 551                  * this is last FCP frame of the sequence.
 552                  */
 553                 if (remaining == 0)
 554                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
 555
 556                 ep = fc_seq_exch(seq);
 557                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
 558                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
 559
 560                 /*
 561                  * send fragment using for a sequence.
 562                  */
 563                 error = lp->tt.seq_send(lp, seq, fp);
 564                 if (error) {
 565                         WARN_ON(1);             /* send error should be rare */
 566                         fc_fcp_retry_cmd(fsp);
 567                         return 0;
 568                 }
 569                 fp = NULL;
 570         }
 571         fsp->xfer_len += seq_blen;      /* premature count? */
 572         return 0;
 573 }
 574
 575 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 576 {
 577         int ba_done = 1;
 578         struct fc_ba_rjt *brp;
 579         struct fc_frame_header *fh;
 580
 581         fh = fc_frame_header_get(fp);
 582         switch (fh->fh_r_ctl) {
 583         case FC_RCTL_BA_ACC:
 584                 break;
 585         case FC_RCTL_BA_RJT:
 586                 brp = fc_frame_payload_get(fp, sizeof(*brp));
 587                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
 588                         break;
 589                 /* fall thru */
 590         default:
 591                 /*
 592                  * we will let the command timeout
 593                  * and scsi-ml recover in this case,
 594                  * therefore cleared the ba_done flag.
 595                  */
 596                 ba_done = 0;
 597         }
 598
 599         if (ba_done) {
 600                 fsp->state |= FC_SRB_ABORTED;
 601                 fsp->state &= ~FC_SRB_ABORT_PENDING;
 602
 603                 if (fsp->wait_for_comp)
 604                         complete(&fsp->tm_done);
 605                 else
 606                         fc_fcp_complete_locked(fsp);
 607         }
 608 }
 609
 610 /**
 611  * fc_fcp_reduce_can_queue() - drop can_queue
 612  * @lp: lport to drop queueing for
 613  *
 614  * If we are getting memory allocation failures, then we may
 615  * be trying to execute too many commands. We let the running
 616  * commands complete or timeout, then try again with a reduced
 617  * can_queue. Eventually we will hit the point where we run
 618  * on all reserved structs.
 619  */
 620 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
 621 {
 622         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 623         unsigned long flags;
 624         int can_queue;
 625
 626         spin_lock_irqsave(lp->host->host_lock, flags);
 627         if (si->throttled)
 628                 goto done;
 629         si->throttled = 1;
 630
 631         can_queue = lp->host->can_queue;
 632         can_queue >>= 1;
 633         if (!can_queue)
 634                 can_queue = 1;
 635         lp->host->can_queue = can_queue;
 636         shost_printk(KERN_ERR, lp->host, "Could not allocate frame.\n"
 637                      "Reducing can_queue to %d.\n", can_queue);
 638 done:
 639         spin_unlock_irqrestore(lp->host->host_lock, flags);
 640 }
 641
 642 /**
 643  * fc_fcp_recv() - Reveive FCP frames
 644  * @seq: The sequence the frame is on
 645  * @fp: The FC frame
 646  * @arg: The related FCP packet
 647  *
 648  * Return   : None
 649  * Context  : called from Soft IRQ context
 650  *            can not called holding list lock
 651  */
 652 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 653 {
 654         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
 655         struct fc_lport *lp;
 656         struct fc_frame_header *fh;
 657         struct fcp_txrdy *dd;
 658         u8 r_ctl;
 659         int rc = 0;
 660
 661         if (IS_ERR(fp))
 662                 goto errout;
 663
 664         fh = fc_frame_header_get(fp);
 665         r_ctl = fh->fh_r_ctl;
 666         lp = fsp->lp;
 667
 668         if (!(lp->state & LPORT_ST_READY))
 669                 goto out;
 670         if (fc_fcp_lock_pkt(fsp))
 671                 goto out;
 672         fsp->last_pkt_time = jiffies;
 673
 674         if (fh->fh_type == FC_TYPE_BLS) {
 675                 fc_fcp_abts_resp(fsp, fp);
 676                 goto unlock;
 677         }
 678
 679         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
 680                 goto unlock;
 681
 682         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
 683                 /*
 684                  * received XFER RDY from the target
 685                  * need to send data to the target
 686                  */
 687                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 688                 dd = fc_frame_payload_get(fp, sizeof(*dd));
 689                 WARN_ON(!dd);
 690
 691                 rc = fc_fcp_send_data(fsp, seq,
 692                                       (size_t) ntohl(dd->ft_data_ro),
 693                                       (size_t) ntohl(dd->ft_burst_len));
 694                 if (!rc)
 695                         seq->rec_data = fsp->xfer_len;
 696                 else if (rc == -ENOMEM)
 697                         fsp->state |= FC_SRB_NOMEM;
 698         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
 699                 /*
 700                  * received a DATA frame
 701                  * next we will copy the data to the system buffer
 702                  */
 703                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
 704                 fc_fcp_recv_data(fsp, fp);
 705                 seq->rec_data = fsp->xfer_contig_end;
 706         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
 707                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 708
 709                 fc_fcp_resp(fsp, fp);
 710         } else {
 711                 FC_DBG("unexpected frame.  r_ctl %x\n", r_ctl);
 712         }
 713 unlock:
 714         fc_fcp_unlock_pkt(fsp);
 715 out:
 716         fc_frame_free(fp);
 717 errout:
 718         if (IS_ERR(fp))
 719                 fc_fcp_error(fsp, fp);
 720         else if (rc == -ENOMEM)
 721                 fc_fcp_reduce_can_queue(lp);
 722 }
 723
 724 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 725 {
 726         struct fc_frame_header *fh;
 727         struct fcp_resp *fc_rp;
 728         struct fcp_resp_ext *rp_ex;
 729         struct fcp_resp_rsp_info *fc_rp_info;
 730         u32 plen;
 731         u32 expected_len;
 732         u32 respl = 0;
 733         u32 snsl = 0;
 734         u8 flags = 0;
 735
 736         plen = fr_len(fp);
 737         fh = (struct fc_frame_header *)fr_hdr(fp);
 738         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
 739                 goto len_err;
 740         plen -= sizeof(*fh);
 741         fc_rp = (struct fcp_resp *)(fh + 1);
 742         fsp->cdb_status = fc_rp->fr_status;
 743         flags = fc_rp->fr_flags;
 744         fsp->scsi_comp_flags = flags;
 745         expected_len = fsp->data_len;
 746
 747         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
 748                 rp_ex = (void *)(fc_rp + 1);
 749                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
 750                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
 751                                 goto len_err;
 752                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
 753                         if (flags & FCP_RSP_LEN_VAL) {
 754                                 respl = ntohl(rp_ex->fr_rsp_len);
 755                                 if (respl != sizeof(*fc_rp_info))
 756                                         goto len_err;
 757                                 if (fsp->wait_for_comp) {
 758                                         /* Abuse cdb_status for rsp code */
 759                                         fsp->cdb_status = fc_rp_info->rsp_code;
 760                                         complete(&fsp->tm_done);
 761                                         /*
 762                                          * tmfs will not have any scsi cmd so
 763                                          * exit here
 764                                          */
 765                                         return;
 766                                 } else
 767                                         goto err;
 768                         }
 769                         if (flags & FCP_SNS_LEN_VAL) {
 770                                 snsl = ntohl(rp_ex->fr_sns_len);
 771                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
 772                                         snsl = SCSI_SENSE_BUFFERSIZE;
 773                                 memcpy(fsp->cmd->sense_buffer,
 774                                        (char *)fc_rp_info + respl, snsl);
 775                         }
 776                 }
 777                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
 778                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
 779                                 goto len_err;
 780                         if (flags & FCP_RESID_UNDER) {
 781                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
 782                                 /*
 783                                  * The cmnd->underflow is the minimum number of
 784                                  * bytes that must be transfered for this
 785                                  * command.  Provided a sense condition is not
 786                                  * present, make sure the actual amount
 787                                  * transferred is at least the underflow value
 788                                  * or fail.
 789                                  */
 790                                 if (!(flags & FCP_SNS_LEN_VAL) &&
 791                                     (fc_rp->fr_status == 0) &&
 792                                     (scsi_bufflen(fsp->cmd) -
 793                                      fsp->scsi_resid) < fsp->cmd->underflow)
 794                                         goto err;
 795                                 expected_len -= fsp->scsi_resid;
 796                         } else {
 797                                 fsp->status_code = FC_ERROR;
 798                         }
 799                 }
 800         }
 801         fsp->state |= FC_SRB_RCV_STATUS;
 802
 803         /*
 804          * Check for missing or extra data frames.
 805          */
 806         if (unlikely(fsp->xfer_len != expected_len)) {
 807                 if (fsp->xfer_len < expected_len) {
 808                         /*
 809                          * Some data may be queued locally,
 810                          * Wait a at least one jiffy to see if it is delivered.
 811                          * If this expires without data, we may do SRR.
 812                          */
 813                         fc_fcp_timer_set(fsp, 2);
 814                         return;
 815                 }
 816                 fsp->status_code = FC_DATA_OVRRUN;
 817                 FC_DBG("tgt %6x xfer len %zx greater than expected len %x. "
 818                        "data len %x\n",
 819                        fsp->rport->port_id,
 820                        fsp->xfer_len, expected_len, fsp->data_len);
 821         }
 822         fc_fcp_complete_locked(fsp);
 823         return;
 824
 825 len_err:
 826         FC_DBG("short FCP response. flags 0x%x len %u respl %u snsl %u\n",
 827                flags, fr_len(fp), respl, snsl);
 828 err:
 829         fsp->status_code = FC_ERROR;
 830         fc_fcp_complete_locked(fsp);
 831 }
 832
 833 /**
 834  * fc_fcp_complete_locked() - complete processing of a fcp packet
 835  * @fsp:        fcp packet
 836  *
 837  * This function may sleep if a timer is pending. The packet lock must be
 838  * held, and the host lock must not be held.
 839  */
 840 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
 841 {
 842         struct fc_lport *lp = fsp->lp;
 843         struct fc_seq *seq;
 844         struct fc_exch *ep;
 845         u32 f_ctl;
 846
 847         if (fsp->state & FC_SRB_ABORT_PENDING)
 848                 return;
 849
 850         if (fsp->state & FC_SRB_ABORTED) {
 851                 if (!fsp->status_code)
 852                         fsp->status_code = FC_CMD_ABORTED;
 853         } else {
 854                 /*
 855                  * Test for transport underrun, independent of response
 856                  * underrun status.
 857                  */
 858                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
 859                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
 860                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
 861                         fsp->status_code = FC_DATA_UNDRUN;
 862                         fsp->io_status = 0;
 863                 }
 864         }
 865
 866         seq = fsp->seq_ptr;
 867         if (seq) {
 868                 fsp->seq_ptr = NULL;
 869                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
 870                         struct fc_frame *conf_frame;
 871                         struct fc_seq *csp;
 872
 873                         csp = lp->tt.seq_start_next(seq);
 874                         conf_frame = fc_frame_alloc(fsp->lp, 0);
 875                         if (conf_frame) {
 876                                 f_ctl = FC_FC_SEQ_INIT;
 877                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
 878                                 ep = fc_seq_exch(seq);
 879                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
 880                                                ep->did, ep->sid,
 881                                                FC_TYPE_FCP, f_ctl, 0);
 882                                 lp->tt.seq_send(lp, csp, conf_frame);
 883                         }
 884                 }
 885                 lp->tt.exch_done(seq);
 886         }
 887         fc_io_compl(fsp);
 888 }
 889
 890 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
 891 {
 892         struct fc_lport *lp = fsp->lp;
 893
 894         if (fsp->seq_ptr) {
 895                 lp->tt.exch_done(fsp->seq_ptr);
 896                 fsp->seq_ptr = NULL;
 897         }
 898         fsp->status_code = error;
 899 }
 900
 901 /**
 902  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
 903  * @lp:         logical port
 904  * @id:         target id
 905  * @lun:        lun
 906  * @error:      fsp status code
 907  *
 908  * If lun or id is -1, they are ignored.
 909  */
 910 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
 911                                     unsigned int lun, int error)
 912 {
 913         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 914         struct fc_fcp_pkt *fsp;
 915         struct scsi_cmnd *sc_cmd;
 916         unsigned long flags;
 917
 918         spin_lock_irqsave(lp->host->host_lock, flags);
 919 restart:
 920         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
 921                 sc_cmd = fsp->cmd;
 922                 if (id != -1 && scmd_id(sc_cmd) != id)
 923                         continue;
 924
 925                 if (lun != -1 && sc_cmd->device->lun != lun)
 926                         continue;
 927
 928                 fc_fcp_pkt_hold(fsp);
 929                 spin_unlock_irqrestore(lp->host->host_lock, flags);
 930
 931                 if (!fc_fcp_lock_pkt(fsp)) {
 932                         fc_fcp_cleanup_cmd(fsp, error);
 933                         fc_io_compl(fsp);
 934                         fc_fcp_unlock_pkt(fsp);
 935                 }
 936
 937                 fc_fcp_pkt_release(fsp);
 938                 spin_lock_irqsave(lp->host->host_lock, flags);
 939                 /*
 940                  * while we dropped the lock multiple pkts could
 941                  * have been released, so we have to start over.
 942                  */
 943                 goto restart;
 944         }
 945         spin_unlock_irqrestore(lp->host->host_lock, flags);
 946 }
 947
 948 static void fc_fcp_abort_io(struct fc_lport *lp)
 949 {
 950         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
 951 }
 952
 953 /**
 954  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
 955  * @lp:         fc lport
 956  * @fsp:        fc packet.
 957  *
 958  * This is called by upper layer protocol.
 959  * Return   : zero for success and -1 for failure
 960  * Context  : called from queuecommand which can be called from process
 961  *            or scsi soft irq.
 962  * Locks    : called with the host lock and irqs disabled.
 963  */
 964 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
 965 {
 966         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 967         int rc;
 968
 969         fsp->cmd->SCp.ptr = (char *)fsp;
 970         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
 971         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
 972
 973         int_to_scsilun(fsp->cmd->device->lun,
 974                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
 975         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
 976         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
 977
 978         spin_unlock_irq(lp->host->host_lock);
 979         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
 980         spin_lock_irq(lp->host->host_lock);
 981         if (rc)
 982                 list_del(&fsp->list);
 983
 984         return rc;
 985 }
 986
 987 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
 988                            void (*resp)(struct fc_seq *,
 989                                         struct fc_frame *fp,
 990                                         void *arg))
 991 {
 992         struct fc_frame *fp;
 993         struct fc_seq *seq;
 994         struct fc_rport *rport;
 995         struct fc_rport_libfc_priv *rp;
 996         const size_t len = sizeof(fsp->cdb_cmd);
 997         int rc = 0;
 998
 999         if (fc_fcp_lock_pkt(fsp))
1000                 return 0;
1001
1002         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1003         if (!fp) {
1004                 rc = -1;
1005                 goto unlock;
1006         }
1007
1008         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1009         fr_cmd(fp) = fsp->cmd;
1010         rport = fsp->rport;
1011         fsp->max_payload = rport->maxframe_size;
1012         rp = rport->dd_data;
1013
1014         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1015                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1016                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1017
1018         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1019         if (!seq) {
1020                 fc_frame_free(fp);
1021                 rc = -1;
1022                 goto unlock;
1023         }
1024         fsp->last_pkt_time = jiffies;
1025         fsp->seq_ptr = seq;
1026         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1027
1028         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1029         fc_fcp_timer_set(fsp,
1030                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1031                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1032 unlock:
1033         fc_fcp_unlock_pkt(fsp);
1034         return rc;
1035 }
1036
1037 /*
1038  * transport error handler
1039  */
1040 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1041 {
1042         int error = PTR_ERR(fp);
1043
1044         if (fc_fcp_lock_pkt(fsp))
1045                 return;
1046
1047         switch (error) {
1048         case -FC_EX_CLOSED:
1049                 fc_fcp_retry_cmd(fsp);
1050                 goto unlock;
1051         default:
1052                 FC_DBG("unknown error %ld\n", PTR_ERR(fp));
1053         }
1054         /*
1055          * clear abort pending, because the lower layer
1056          * decided to force completion.
1057          */
1058         fsp->state &= ~FC_SRB_ABORT_PENDING;
1059         fsp->status_code = FC_CMD_PLOGO;
1060         fc_fcp_complete_locked(fsp);
1061 unlock:
1062         fc_fcp_unlock_pkt(fsp);
1063 }
1064
1065 /*
1066  * Scsi abort handler- calls to send an abort
1067  * and then wait for abort completion
1068  */
1069 static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1070 {
1071         int rc = FAILED;
1072
1073         if (fc_fcp_send_abort(fsp))
1074                 return FAILED;
1075
1076         init_completion(&fsp->tm_done);
1077         fsp->wait_for_comp = 1;
1078
1079         spin_unlock_bh(&fsp->scsi_pkt_lock);
1080         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1081         spin_lock_bh(&fsp->scsi_pkt_lock);
1082         fsp->wait_for_comp = 0;
1083
1084         if (!rc) {
1085                 FC_DBG("target abort cmd  failed\n");
1086                 rc = FAILED;
1087         } else if (fsp->state & FC_SRB_ABORTED) {
1088                 FC_DBG("target abort cmd  passed\n");
1089                 rc = SUCCESS;
1090                 fc_fcp_complete_locked(fsp);
1091         }
1092
1093         return rc;
1094 }
1095
1096 /*
1097  * Retry LUN reset after resource allocation failed.
1098  */
1099 static void fc_lun_reset_send(unsigned long data)
1100 {
1101         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1102         struct fc_lport *lp = fsp->lp;
1103         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1104                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1105                         return;
1106                 if (fc_fcp_lock_pkt(fsp))
1107                         return;
1108                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1109                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1110                 fc_fcp_unlock_pkt(fsp);
1111         }
1112 }
1113
1114 /*
1115  * Scsi device reset handler- send a LUN RESET to the device
1116  * and wait for reset reply
1117  */
1118 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1119                         unsigned int id, unsigned int lun)
1120 {
1121         int rc;
1122
1123         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1124         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1125         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1126
1127         fsp->wait_for_comp = 1;
1128         init_completion(&fsp->tm_done);
1129
1130         fc_lun_reset_send((unsigned long)fsp);
1131
1132         /*
1133          * wait for completion of reset
1134          * after that make sure all commands are terminated
1135          */
1136         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1137
1138         spin_lock_bh(&fsp->scsi_pkt_lock);
1139         fsp->state |= FC_SRB_COMPL;
1140         spin_unlock_bh(&fsp->scsi_pkt_lock);
1141
1142         del_timer_sync(&fsp->timer);
1143
1144         spin_lock_bh(&fsp->scsi_pkt_lock);
1145         if (fsp->seq_ptr) {
1146                 lp->tt.exch_done(fsp->seq_ptr);
1147                 fsp->seq_ptr = NULL;
1148         }
1149         fsp->wait_for_comp = 0;
1150         spin_unlock_bh(&fsp->scsi_pkt_lock);
1151
1152         if (!rc) {
1153                 FC_DBG("lun reset failed\n");
1154                 return FAILED;
1155         }
1156
1157         /* cdb_status holds the tmf's rsp code */
1158         if (fsp->cdb_status != FCP_TMF_CMPL)
1159                 return FAILED;
1160
1161         FC_DBG("lun reset to lun %u completed\n", lun);
1162         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1163         return SUCCESS;
1164 }
1165
1166 /*
1167  * Task Managment response handler
1168  */
1169 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1170 {
1171         struct fc_fcp_pkt *fsp = arg;
1172         struct fc_frame_header *fh;
1173
1174         if (IS_ERR(fp)) {
1175                 /*
1176                  * If there is an error just let it timeout or wait
1177                  * for TMF to be aborted if it timedout.
1178                  *
1179                  * scsi-eh will escalate for when either happens.
1180                  */
1181                 return;
1182         }
1183
1184         if (fc_fcp_lock_pkt(fsp))
1185                 return;
1186
1187         /*
1188          * raced with eh timeout handler.
1189          */
1190         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1191                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1192                 return;
1193         }
1194
1195         fh = fc_frame_header_get(fp);
1196         if (fh->fh_type != FC_TYPE_BLS)
1197                 fc_fcp_resp(fsp, fp);
1198         fsp->seq_ptr = NULL;
1199         fsp->lp->tt.exch_done(seq);
1200         fc_frame_free(fp);
1201         fc_fcp_unlock_pkt(fsp);
1202 }
1203
1204 static void fc_fcp_cleanup(struct fc_lport *lp)
1205 {
1206         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1207 }
1208
1209 /*
1210  * fc_fcp_timeout: called by OS timer function.
1211  *
1212  * The timer has been inactivated and must be reactivated if desired
1213  * using fc_fcp_timer_set().
1214  *
1215  * Algorithm:
1216  *
1217  * If REC is supported, just issue it, and return.  The REC exchange will
1218  * complete or time out, and recovery can continue at that point.
1219  *
1220  * Otherwise, if the response has been received without all the data,
1221  * it has been ER_TIMEOUT since the response was received.
1222  *
1223  * If the response has not been received,
1224  * we see if data was received recently.  If it has been, we continue waiting,
1225  * otherwise, we abort the command.
1226  */
1227 static void fc_fcp_timeout(unsigned long data)
1228 {
1229         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1230         struct fc_rport *rport = fsp->rport;
1231         struct fc_rport_libfc_priv *rp = rport->dd_data;
1232
1233         if (fc_fcp_lock_pkt(fsp))
1234                 return;
1235
1236         if (fsp->cdb_cmd.fc_tm_flags)
1237                 goto unlock;
1238
1239         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1240
1241         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1242                 fc_fcp_rec(fsp);
1243         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1244                                jiffies))
1245                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1246         else if (fsp->state & FC_SRB_RCV_STATUS)
1247                 fc_fcp_complete_locked(fsp);
1248         else
1249                 fc_timeout_error(fsp);
1250         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1251 unlock:
1252         fc_fcp_unlock_pkt(fsp);
1253 }
1254
1255 /*
1256  * Send a REC ELS request
1257  */
1258 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1259 {
1260         struct fc_lport *lp;
1261         struct fc_frame *fp;
1262         struct fc_rport *rport;
1263         struct fc_rport_libfc_priv *rp;
1264
1265         lp = fsp->lp;
1266         rport = fsp->rport;
1267         rp = rport->dd_data;
1268         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1269                 fsp->status_code = FC_HRD_ERROR;
1270                 fsp->io_status = 0;
1271                 fc_fcp_complete_locked(fsp);
1272                 return;
1273         }
1274         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1275         if (!fp)
1276                 goto retry;
1277
1278         fr_seq(fp) = fsp->seq_ptr;
1279         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1280                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1281                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1282         if (lp->tt.elsct_send(lp, rport, fp, ELS_REC, fc_fcp_rec_resp,
1283                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1284                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1285                 return;
1286         }
1287         fc_frame_free(fp);
1288 retry:
1289         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1290                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1291         else
1292                 fc_timeout_error(fsp);
1293 }
1294
1295 /*
1296  * Receive handler for REC ELS frame
1297  * if it is a reject then let the scsi layer to handle
1298  * the timeout. if it is a LS_ACC then if the io was not completed
1299  * then set the timeout and return otherwise complete the exchange
1300  * and tell the scsi layer to restart the I/O.
1301  */
1302 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1303 {
1304         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1305         struct fc_els_rec_acc *recp;
1306         struct fc_els_ls_rjt *rjt;
1307         u32 e_stat;
1308         u8 opcode;
1309         u32 offset;
1310         enum dma_data_direction data_dir;
1311         enum fc_rctl r_ctl;
1312         struct fc_rport_libfc_priv *rp;
1313
1314         if (IS_ERR(fp)) {
1315                 fc_fcp_rec_error(fsp, fp);
1316                 return;
1317         }
1318
1319         if (fc_fcp_lock_pkt(fsp))
1320                 goto out;
1321
1322         fsp->recov_retry = 0;
1323         opcode = fc_frame_payload_op(fp);
1324         if (opcode == ELS_LS_RJT) {
1325                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1326                 switch (rjt->er_reason) {
1327                 default:
1328                         FC_DEBUG_FCP("device %x unexpected REC reject "
1329                                      "reason %d expl %d\n",
1330                                      fsp->rport->port_id, rjt->er_reason,
1331                                      rjt->er_explan);
1332                         /* fall through */
1333                 case ELS_RJT_UNSUP:
1334                         FC_DEBUG_FCP("device does not support REC\n");
1335                         rp = fsp->rport->dd_data;
1336                         /*
1337                          * if we do not spport RECs or got some bogus
1338                          * reason then resetup timer so we check for
1339                          * making progress.
1340                          */
1341                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1342                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1343                         break;
1344                 case ELS_RJT_LOGIC:
1345                 case ELS_RJT_UNAB:
1346                         /*
1347                          * If no data transfer, the command frame got dropped
1348                          * so we just retry.  If data was transferred, we
1349                          * lost the response but the target has no record,
1350                          * so we abort and retry.
1351                          */
1352                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1353                             fsp->xfer_len == 0) {
1354                                 fc_fcp_retry_cmd(fsp);
1355                                 break;
1356                         }
1357                         fc_timeout_error(fsp);
1358                         break;
1359                 }
1360         } else if (opcode == ELS_LS_ACC) {
1361                 if (fsp->state & FC_SRB_ABORTED)
1362                         goto unlock_out;
1363
1364                 data_dir = fsp->cmd->sc_data_direction;
1365                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1366                 offset = ntohl(recp->reca_fc4value);
1367                 e_stat = ntohl(recp->reca_e_stat);
1368
1369                 if (e_stat & ESB_ST_COMPLETE) {
1370
1371                         /*
1372                          * The exchange is complete.
1373                          *
1374                          * For output, we must've lost the response.
1375                          * For input, all data must've been sent.
1376                          * We lost may have lost the response
1377                          * (and a confirmation was requested) and maybe
1378                          * some data.
1379                          *
1380                          * If all data received, send SRR
1381                          * asking for response.  If partial data received,
1382                          * or gaps, SRR requests data at start of gap.
1383                          * Recovery via SRR relies on in-order-delivery.
1384                          */
1385                         if (data_dir == DMA_TO_DEVICE) {
1386                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1387                         } else if (fsp->xfer_contig_end == offset) {
1388                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1389                         } else {
1390                                 offset = fsp->xfer_contig_end;
1391                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1392                         }
1393                         fc_fcp_srr(fsp, r_ctl, offset);
1394                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1395
1396                         /*
1397                          * The remote port has the initiative, so just
1398                          * keep waiting for it to complete.
1399                          */
1400                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1401                 } else {
1402
1403                         /*
1404                          * The exchange is incomplete, we have seq. initiative.
1405                          * Lost response with requested confirmation,
1406                          * lost confirmation, lost transfer ready or
1407                          * lost write data.
1408                          *
1409                          * For output, if not all data was received, ask
1410                          * for transfer ready to be repeated.
1411                          *
1412                          * If we received or sent all the data, send SRR to
1413                          * request response.
1414                          *
1415                          * If we lost a response, we may have lost some read
1416                          * data as well.
1417                          */
1418                         r_ctl = FC_RCTL_DD_SOL_DATA;
1419                         if (data_dir == DMA_TO_DEVICE) {
1420                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1421                                 if (offset < fsp->data_len)
1422                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1423                         } else if (offset == fsp->xfer_contig_end) {
1424                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1425                         } else if (fsp->xfer_contig_end < offset) {
1426                                 offset = fsp->xfer_contig_end;
1427                         }
1428                         fc_fcp_srr(fsp, r_ctl, offset);
1429                 }
1430         }
1431 unlock_out:
1432         fc_fcp_unlock_pkt(fsp);
1433 out:
1434         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1435         fc_frame_free(fp);
1436 }
1437
1438 /*
1439  * Handle error response or timeout for REC exchange.
1440  */
1441 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1442 {
1443         int error = PTR_ERR(fp);
1444
1445         if (fc_fcp_lock_pkt(fsp))
1446                 goto out;
1447
1448         switch (error) {
1449         case -FC_EX_CLOSED:
1450                 fc_fcp_retry_cmd(fsp);
1451                 break;
1452
1453         default:
1454                 FC_DBG("REC %p fid %x error unexpected error %d\n",
1455                        fsp, fsp->rport->port_id, error);
1456                 fsp->status_code = FC_CMD_PLOGO;
1457                 /* fall through */
1458
1459         case -FC_EX_TIMEOUT:
1460                 /*
1461                  * Assume REC or LS_ACC was lost.
1462                  * The exchange manager will have aborted REC, so retry.
1463                  */
1464                 FC_DBG("REC fid %x error error %d retry %d/%d\n",
1465                        fsp->rport->port_id, error, fsp->recov_retry,
1466                        FC_MAX_RECOV_RETRY);
1467                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1468                         fc_fcp_rec(fsp);
1469                 else
1470                         fc_timeout_error(fsp);
1471                 break;
1472         }
1473         fc_fcp_unlock_pkt(fsp);
1474 out:
1475         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1476 }
1477
1478 /*
1479  * Time out error routine:
1480  * abort's the I/O close the exchange and
1481  * send completion notification to scsi layer
1482  */
1483 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1484 {
1485         fsp->status_code = FC_CMD_TIME_OUT;
1486         fsp->cdb_status = 0;
1487         fsp->io_status = 0;
1488         /*
1489          * if this fails then we let the scsi command timer fire and
1490          * scsi-ml escalate.
1491          */
1492         fc_fcp_send_abort(fsp);
1493 }
1494
1495 /*
1496  * Sequence retransmission request.
1497  * This is called after receiving status but insufficient data, or
1498  * when expecting status but the request has timed out.
1499  */
1500 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1501 {
1502         struct fc_lport *lp = fsp->lp;
1503         struct fc_rport *rport;
1504         struct fc_rport_libfc_priv *rp;
1505         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1506         struct fc_seq *seq;
1507         struct fcp_srr *srr;
1508         struct fc_frame *fp;
1509         u8 cdb_op;
1510
1511         rport = fsp->rport;
1512         rp = rport->dd_data;
1513         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1514
1515         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1516                 goto retry;                     /* shouldn't happen */
1517         fp = fc_frame_alloc(lp, sizeof(*srr));
1518         if (!fp)
1519                 goto retry;
1520
1521         srr = fc_frame_payload_get(fp, sizeof(*srr));
1522         memset(srr, 0, sizeof(*srr));
1523         srr->srr_op = ELS_SRR;
1524         srr->srr_ox_id = htons(ep->oxid);
1525         srr->srr_rx_id = htons(ep->rxid);
1526         srr->srr_r_ctl = r_ctl;
1527         srr->srr_rel_off = htonl(offset);
1528
1529         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1530                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1531                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1532
1533         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1534                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1535         if (!seq) {
1536                 fc_frame_free(fp);
1537                 goto retry;
1538         }
1539         fsp->recov_seq = seq;
1540         fsp->xfer_len = offset;
1541         fsp->xfer_contig_end = offset;
1542         fsp->state &= ~FC_SRB_RCV_STATUS;
1543         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1544         return;
1545 retry:
1546         fc_fcp_retry_cmd(fsp);
1547 }
1548
1549 /*
1550  * Handle response from SRR.
1551  */
1552 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1553 {
1554         struct fc_fcp_pkt *fsp = arg;
1555         struct fc_frame_header *fh;
1556
1557         if (IS_ERR(fp)) {
1558                 fc_fcp_srr_error(fsp, fp);
1559                 return;
1560         }
1561
1562         if (fc_fcp_lock_pkt(fsp))
1563                 goto out;
1564
1565         fh = fc_frame_header_get(fp);
1566         /*
1567          * BUG? fc_fcp_srr_error calls exch_done which would release
1568          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1569          * then fc_exch_timeout would be sending an abort. The exch_done
1570          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1571          * an abort response though.
1572          */
1573         if (fh->fh_type == FC_TYPE_BLS) {
1574                 fc_fcp_unlock_pkt(fsp);
1575                 return;
1576         }
1577
1578         fsp->recov_seq = NULL;
1579         switch (fc_frame_payload_op(fp)) {
1580         case ELS_LS_ACC:
1581                 fsp->recov_retry = 0;
1582                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1583                 break;
1584         case ELS_LS_RJT:
1585         default:
1586                 fc_timeout_error(fsp);
1587                 break;
1588         }
1589         fc_fcp_unlock_pkt(fsp);
1590         fsp->lp->tt.exch_done(seq);
1591 out:
1592         fc_frame_free(fp);
1593         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1594 }
1595
1596 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1597 {
1598         if (fc_fcp_lock_pkt(fsp))
1599                 goto out;
1600         fsp->lp->tt.exch_done(fsp->recov_seq);
1601         fsp->recov_seq = NULL;
1602         switch (PTR_ERR(fp)) {
1603         case -FC_EX_TIMEOUT:
1604                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1605                         fc_fcp_rec(fsp);
1606                 else
1607                         fc_timeout_error(fsp);
1608                 break;
1609         case -FC_EX_CLOSED:                     /* e.g., link failure */
1610                 /* fall through */
1611         default:
1612                 fc_fcp_retry_cmd(fsp);
1613                 break;
1614         }
1615         fc_fcp_unlock_pkt(fsp);
1616 out:
1617         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1618 }
1619
1620 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1621 {
1622         /* lock ? */
1623         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1624 }
1625
1626 /**
1627  * fc_queuecommand - The queuecommand function of the scsi template
1628  * @cmd:        struct scsi_cmnd to be executed
1629  * @done:       Callback function to be called when cmd is completed
1630  *
1631  * this is the i/o strategy routine, called by the scsi layer
1632  * this routine is called with holding the host_lock.
1633  */
1634 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1635 {
1636         struct fc_lport *lp;
1637         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1638         struct fc_fcp_pkt *fsp;
1639         struct fc_rport_libfc_priv *rp;
1640         int rval;
1641         int rc = 0;
1642         struct fcoe_dev_stats *stats;
1643
1644         lp = shost_priv(sc_cmd->device->host);
1645
1646         rval = fc_remote_port_chkready(rport);
1647         if (rval) {
1648                 sc_cmd->result = rval;
1649                 done(sc_cmd);
1650                 goto out;
1651         }
1652
1653         if (!*(struct fc_remote_port **)rport->dd_data) {
1654                 /*
1655                  * rport is transitioning from blocked/deleted to
1656                  * online
1657                  */
1658                 sc_cmd->result = DID_IMM_RETRY << 16;
1659                 done(sc_cmd);
1660                 goto out;
1661         }
1662
1663         rp = rport->dd_data;
1664
1665         if (!fc_fcp_lport_queue_ready(lp)) {
1666                 rc = SCSI_MLQUEUE_HOST_BUSY;
1667                 goto out;
1668         }
1669
1670         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1671         if (fsp == NULL) {
1672                 rc = SCSI_MLQUEUE_HOST_BUSY;
1673                 goto out;
1674         }
1675
1676         /*
1677          * build the libfc request pkt
1678          */
1679         fsp->cmd = sc_cmd;      /* save the cmd */
1680         fsp->lp = lp;           /* save the softc ptr */
1681         fsp->rport = rport;     /* set the remote port ptr */
1682         sc_cmd->scsi_done = done;
1683
1684         /*
1685          * set up the transfer length
1686          */
1687         fsp->data_len = scsi_bufflen(sc_cmd);
1688         fsp->xfer_len = 0;
1689
1690         /*
1691          * setup the data direction
1692          */
1693         stats = lp->dev_stats[smp_processor_id()];
1694         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1695                 fsp->req_flags = FC_SRB_READ;
1696                 stats->InputRequests++;
1697                 stats->InputMegabytes = fsp->data_len;
1698         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1699                 fsp->req_flags = FC_SRB_WRITE;
1700                 stats->OutputRequests++;
1701                 stats->OutputMegabytes = fsp->data_len;
1702         } else {
1703                 fsp->req_flags = 0;
1704                 stats->ControlRequests++;
1705         }
1706
1707         fsp->tgt_flags = rp->flags;
1708
1709         init_timer(&fsp->timer);
1710         fsp->timer.data = (unsigned long)fsp;
1711
1712         /*
1713          * send it to the lower layer
1714          * if we get -1 return then put the request in the pending
1715          * queue.
1716          */
1717         rval = fc_fcp_pkt_send(lp, fsp);
1718         if (rval != 0) {
1719                 fsp->state = FC_SRB_FREE;
1720                 fc_fcp_pkt_release(fsp);
1721                 rc = SCSI_MLQUEUE_HOST_BUSY;
1722         }
1723 out:
1724         return rc;
1725 }
1726 EXPORT_SYMBOL(fc_queuecommand);
1727
1728 /**
1729  * fc_io_compl() -  Handle responses for completed commands
1730  * @fsp:        scsi packet
1731  *
1732  * Translates a error to a Linux SCSI error.
1733  *
1734  * The fcp packet lock must be held when calling.
1735  */
1736 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1737 {
1738         struct fc_fcp_internal *si;
1739         struct scsi_cmnd *sc_cmd;
1740         struct fc_lport *lp;
1741         unsigned long flags;
1742
1743         fsp->state |= FC_SRB_COMPL;
1744         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1745                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1746                 del_timer_sync(&fsp->timer);
1747                 spin_lock_bh(&fsp->scsi_pkt_lock);
1748         }
1749
1750         lp = fsp->lp;
1751         si = fc_get_scsi_internal(lp);
1752         spin_lock_irqsave(lp->host->host_lock, flags);
1753         if (!fsp->cmd) {
1754                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1755                 return;
1756         }
1757
1758         /*
1759          * if a command timed out while we had to try and throttle IO
1760          * and it is now getting cleaned up, then we are about to
1761          * try again so clear the throttled flag incase we get more
1762          * time outs.
1763          */
1764         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1765                 si->throttled = 0;
1766
1767         sc_cmd = fsp->cmd;
1768         fsp->cmd = NULL;
1769
1770         if (!sc_cmd->SCp.ptr) {
1771                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1772                 return;
1773         }
1774
1775         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1776         switch (fsp->status_code) {
1777         case FC_COMPLETE:
1778                 if (fsp->cdb_status == 0) {
1779                         /*
1780                          * good I/O status
1781                          */
1782                         sc_cmd->result = DID_OK << 16;
1783                         if (fsp->scsi_resid)
1784                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1785                 } else if (fsp->cdb_status == QUEUE_FULL) {
1786                         struct scsi_device *tmp_sdev;
1787                         struct scsi_device *sdev = sc_cmd->device;
1788
1789                         shost_for_each_device(tmp_sdev, sdev->host) {
1790                                 if (tmp_sdev->id != sdev->id)
1791                                         continue;
1792
1793                                 if (tmp_sdev->queue_depth > 1) {
1794                                         scsi_track_queue_full(tmp_sdev,
1795                                                               tmp_sdev->
1796                                                               queue_depth - 1);
1797                                 }
1798                         }
1799                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1800                 } else {
1801                         /*
1802                          * transport level I/O was ok but scsi
1803                          * has non zero status
1804                          */
1805                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1806                 }
1807                 break;
1808         case FC_ERROR:
1809                 sc_cmd->result = DID_ERROR << 16;
1810                 break;
1811         case FC_DATA_UNDRUN:
1812                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1813                         /*
1814                          * scsi status is good but transport level
1815                          * underrun.
1816                          */
1817                         sc_cmd->result = DID_OK << 16;
1818                 } else {
1819                         /*
1820                          * scsi got underrun, this is an error
1821                          */
1822                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1823                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1824                 }
1825                 break;
1826         case FC_DATA_OVRRUN:
1827                 /*
1828                  * overrun is an error
1829                  */
1830                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1831                 break;
1832         case FC_CMD_ABORTED:
1833                 sc_cmd->result = (DID_ABORT << 16) | fsp->io_status;
1834                 break;
1835         case FC_CMD_TIME_OUT:
1836                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1837                 break;
1838         case FC_CMD_RESET:
1839                 sc_cmd->result = (DID_RESET << 16);
1840                 break;
1841         case FC_HRD_ERROR:
1842                 sc_cmd->result = (DID_NO_CONNECT << 16);
1843                 break;
1844         default:
1845                 sc_cmd->result = (DID_ERROR << 16);
1846                 break;
1847         }
1848
1849         list_del(&fsp->list);
1850         sc_cmd->SCp.ptr = NULL;
1851         sc_cmd->scsi_done(sc_cmd);
1852         spin_unlock_irqrestore(lp->host->host_lock, flags);
1853
1854         /* release ref from initial allocation in queue command */
1855         fc_fcp_pkt_release(fsp);
1856 }
1857
1858 /**
1859  * fc_fcp_complete() - complete processing of a fcp packet
1860  * @fsp:        fcp packet
1861  *
1862  * This function may sleep if a fsp timer is pending.
1863  * The host lock must not be held by caller.
1864  */
1865 void fc_fcp_complete(struct fc_fcp_pkt *fsp)
1866 {
1867         if (fc_fcp_lock_pkt(fsp))
1868                 return;
1869
1870         fc_fcp_complete_locked(fsp);
1871         fc_fcp_unlock_pkt(fsp);
1872 }
1873 EXPORT_SYMBOL(fc_fcp_complete);
1874
1875 /**
1876  * fc_eh_abort() - Abort a command
1877  * @sc_cmd:     scsi command to abort
1878  *
1879  * From scsi host template.
1880  * send ABTS to the target device  and wait for the response
1881  * sc_cmd is the pointer to the command to be aborted.
1882  */
1883 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1884 {
1885         struct fc_fcp_pkt *fsp;
1886         struct fc_lport *lp;
1887         int rc = FAILED;
1888         unsigned long flags;
1889
1890         lp = shost_priv(sc_cmd->device->host);
1891         if (lp->state != LPORT_ST_READY)
1892                 return rc;
1893         else if (!lp->link_up)
1894                 return rc;
1895
1896         spin_lock_irqsave(lp->host->host_lock, flags);
1897         fsp = CMD_SP(sc_cmd);
1898         if (!fsp) {
1899                 /* command completed while scsi eh was setting up */
1900                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1901                 return SUCCESS;
1902         }
1903         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1904         fc_fcp_pkt_hold(fsp);
1905         spin_unlock_irqrestore(lp->host->host_lock, flags);
1906
1907         if (fc_fcp_lock_pkt(fsp)) {
1908                 /* completed while we were waiting for timer to be deleted */
1909                 rc = SUCCESS;
1910                 goto release_pkt;
1911         }
1912
1913         rc = fc_fcp_pkt_abort(lp, fsp);
1914         fc_fcp_unlock_pkt(fsp);
1915
1916 release_pkt:
1917         fc_fcp_pkt_release(fsp);
1918         return rc;
1919 }
1920 EXPORT_SYMBOL(fc_eh_abort);
1921
1922 /**
1923  * fc_eh_device_reset() Reset a single LUN
1924  * @sc_cmd:     scsi command
1925  *
1926  * Set from scsi host template to send tm cmd to the target and wait for the
1927  * response.
1928  */
1929 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1930 {
1931         struct fc_lport *lp;
1932         struct fc_fcp_pkt *fsp;
1933         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1934         int rc = FAILED;
1935         struct fc_rport_libfc_priv *rp;
1936         int rval;
1937
1938         rval = fc_remote_port_chkready(rport);
1939         if (rval)
1940                 goto out;
1941
1942         rp = rport->dd_data;
1943         lp = shost_priv(sc_cmd->device->host);
1944
1945         if (lp->state != LPORT_ST_READY)
1946                 return rc;
1947
1948         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
1949         if (fsp == NULL) {
1950                 FC_DBG("could not allocate scsi_pkt\n");
1951                 sc_cmd->result = DID_NO_CONNECT << 16;
1952                 goto out;
1953         }
1954
1955         /*
1956          * Build the libfc request pkt. Do not set the scsi cmnd, because
1957          * the sc passed in is not setup for execution like when sent
1958          * through the queuecommand callout.
1959          */
1960         fsp->lp = lp;           /* save the softc ptr */
1961         fsp->rport = rport;     /* set the remote port ptr */
1962
1963         /*
1964          * flush outstanding commands
1965          */
1966         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
1967         fsp->state = FC_SRB_FREE;
1968         fc_fcp_pkt_release(fsp);
1969
1970 out:
1971         return rc;
1972 }
1973 EXPORT_SYMBOL(fc_eh_device_reset);
1974
1975 /**
1976  * fc_eh_host_reset() - The reset function will reset the ports on the host.
1977  * @sc_cmd:     scsi command
1978  */
1979 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
1980 {
1981         struct Scsi_Host *shost = sc_cmd->device->host;
1982         struct fc_lport *lp = shost_priv(shost);
1983         unsigned long wait_tmo;
1984
1985         lp->tt.lport_reset(lp);
1986         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
1987         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
1988                 msleep(1000);
1989
1990         if (fc_fcp_lport_queue_ready(lp)) {
1991                 shost_printk(KERN_INFO, shost, "Host reset succeeded.\n");
1992                 return SUCCESS;
1993         } else {
1994                 shost_printk(KERN_INFO, shost, "Host reset failed. "
1995                              "lport not ready.\n");
1996                 return FAILED;
1997         }
1998 }
1999 EXPORT_SYMBOL(fc_eh_host_reset);
2000
2001 /**
2002  * fc_slave_alloc() - configure queue depth
2003  * @sdev:       scsi device
2004  *
2005  * Configures queue depth based on host's cmd_per_len. If not set
2006  * then we use the libfc default.
2007  */
2008 int fc_slave_alloc(struct scsi_device *sdev)
2009 {
2010         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2011         int queue_depth;
2012
2013         if (!rport || fc_remote_port_chkready(rport))
2014                 return -ENXIO;
2015
2016         if (sdev->tagged_supported) {
2017                 if (sdev->host->hostt->cmd_per_lun)
2018                         queue_depth = sdev->host->hostt->cmd_per_lun;
2019                 else
2020                         queue_depth = FC_FCP_DFLT_QUEUE_DEPTH;
2021                 scsi_activate_tcq(sdev, queue_depth);
2022         }
2023         return 0;
2024 }
2025 EXPORT_SYMBOL(fc_slave_alloc);
2026
2027 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
2028 {
2029         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2030         return sdev->queue_depth;
2031 }
2032 EXPORT_SYMBOL(fc_change_queue_depth);
2033
2034 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2035 {
2036         if (sdev->tagged_supported) {
2037                 scsi_set_tag_type(sdev, tag_type);
2038                 if (tag_type)
2039                         scsi_activate_tcq(sdev, sdev->queue_depth);
2040                 else
2041                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2042         } else
2043                 tag_type = 0;
2044
2045         return tag_type;
2046 }
2047 EXPORT_SYMBOL(fc_change_queue_type);
2048
2049 void fc_fcp_destroy(struct fc_lport *lp)
2050 {
2051         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2052
2053         if (!list_empty(&si->scsi_pkt_queue))
2054                 printk(KERN_ERR "Leaked scsi packets.\n");
2055
2056         mempool_destroy(si->scsi_pkt_pool);
2057         kfree(si);
2058         lp->scsi_priv = NULL;
2059 }
2060 EXPORT_SYMBOL(fc_fcp_destroy);
2061
2062 int fc_fcp_init(struct fc_lport *lp)
2063 {
2064         int rc;
2065         struct fc_fcp_internal *si;
2066
2067         if (!lp->tt.fcp_cmd_send)
2068                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2069
2070         if (!lp->tt.fcp_cleanup)
2071                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2072
2073         if (!lp->tt.fcp_abort_io)
2074                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2075
2076         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2077         if (!si)
2078                 return -ENOMEM;
2079         lp->scsi_priv = si;
2080         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2081
2082         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2083         if (!si->scsi_pkt_pool) {
2084                 rc = -ENOMEM;
2085                 goto free_internal;
2086         }
2087         return 0;
2088
2089 free_internal:
2090         kfree(si);
2091         return rc;
2092 }
2093 EXPORT_SYMBOL(fc_fcp_init);
2094
2095 static int __init libfc_init(void)
2096 {
2097         int rc;
2098
2099         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2100                                             sizeof(struct fc_fcp_pkt),
2101                                             0, SLAB_HWCACHE_ALIGN, NULL);
2102         if (scsi_pkt_cachep == NULL) {
2103                 FC_DBG("Unable to allocate SRB cache...module load failed!");
2104                 return -ENOMEM;
2105         }
2106
2107         rc = fc_setup_exch_mgr();
2108         if (rc)
2109                 goto destroy_pkt_cache;
2110
2111         rc = fc_setup_rport();
2112         if (rc)
2113                 goto destroy_em;
2114
2115         return rc;
2116 destroy_em:
2117         fc_destroy_exch_mgr();
2118 destroy_pkt_cache:
2119         kmem_cache_destroy(scsi_pkt_cachep);
2120         return rc;
2121 }
2122
2123 static void __exit libfc_exit(void)
2124 {
2125         kmem_cache_destroy(scsi_pkt_cachep);
2126         fc_destroy_exch_mgr();
2127         fc_destroy_rport();
2128 }
2129
2130 module_init(libfc_init);
2131 module_exit(libfc_exit);