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