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 v2");
  45
  46 unsigned int fc_debug_logging;
  47 module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR);
  48 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
  49
  50 static struct kmem_cache *scsi_pkt_cachep;
  51
  52 /* SRB state definitions */
  53 #define FC_SRB_FREE             0               /* cmd is free */
  54 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
  55 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
  56 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
  57 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
  58 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
  59 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
  60 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
  61 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
  62
  63 #define FC_SRB_READ             (1 << 1)
  64 #define FC_SRB_WRITE            (1 << 0)
  65
  66 /*
  67  * The SCp.ptr should be tested and set under the host lock. NULL indicates
  68  * that the command has been retruned to the scsi layer.
  69  */
  70 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
  71 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
  72 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
  73 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
  74 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
  75
  76 struct fc_fcp_internal {
  77         mempool_t       *scsi_pkt_pool;
  78         struct list_head scsi_pkt_queue;
  79         u8              throttled;
  80 };
  81
  82 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
  83
  84 /*
  85  * function prototypes
  86  * FC scsi I/O related functions
  87  */
  88 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
  89 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
  90 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
  91 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
  92 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
  93 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
  94 static void fc_timeout_error(struct fc_fcp_pkt *);
  95 static void fc_fcp_timeout(unsigned long data);
  96 static void fc_fcp_rec(struct fc_fcp_pkt *);
  97 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
  98 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
  99 static void fc_io_compl(struct fc_fcp_pkt *);
 100
 101 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
 102 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
 103 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
 104
 105 /*
 106  * command status codes
 107  */
 108 #define FC_COMPLETE             0
 109 #define FC_CMD_ABORTED          1
 110 #define FC_CMD_RESET            2
 111 #define FC_CMD_PLOGO            3
 112 #define FC_SNS_RCV              4
 113 #define FC_TRANS_ERR            5
 114 #define FC_DATA_OVRRUN          6
 115 #define FC_DATA_UNDRUN          7
 116 #define FC_ERROR                8
 117 #define FC_HRD_ERROR            9
 118 #define FC_CMD_TIME_OUT         10
 119
 120 /*
 121  * Error recovery timeout values.
 122  */
 123 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 124 #define FC_SCSI_TM_TOV          (10 * HZ)
 125 #define FC_SCSI_REC_TOV         (2 * HZ)
 126 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 127
 128 #define FC_MAX_ERROR_CNT        5
 129 #define FC_MAX_RECOV_RETRY      3
 130
 131 #define FC_FCP_DFLT_QUEUE_DEPTH 32
 132
 133 /**
 134  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 135  * @lp:         fc lport struct
 136  * @gfp:        gfp flags for allocation
 137  *
 138  * This is used by upper layer scsi driver.
 139  * Return Value : scsi_pkt structure or null on allocation failure.
 140  * Context      : call from process context. no locking required.
 141  */
 142 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
 143 {
 144         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 145         struct fc_fcp_pkt *fsp;
 146
 147         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
 148         if (fsp) {
 149                 memset(fsp, 0, sizeof(*fsp));
 150                 fsp->lp = lp;
 151                 atomic_set(&fsp->ref_cnt, 1);
 152                 init_timer(&fsp->timer);
 153                 INIT_LIST_HEAD(&fsp->list);
 154                 spin_lock_init(&fsp->scsi_pkt_lock);
 155         }
 156         return fsp;
 157 }
 158
 159 /**
 160  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
 161  * @fsp:        fcp packet struct
 162  *
 163  * This is used by upper layer scsi driver.
 164  * Context      : call from process  and interrupt context.
 165  *                no locking required
 166  */
 167 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
 168 {
 169         if (atomic_dec_and_test(&fsp->ref_cnt)) {
 170                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
 171
 172                 mempool_free(fsp, si->scsi_pkt_pool);
 173         }
 174 }
 175
 176 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
 177 {
 178         atomic_inc(&fsp->ref_cnt);
 179 }
 180
 181 /**
 182  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
 183  * @seq:                exchange sequence
 184  * @fsp:        fcp packet struct
 185  *
 186  * Release hold on scsi_pkt packet set to keep scsi_pkt
 187  * till EM layer exch resource is not freed.
 188  * Context      : called from from EM layer.
 189  *                no locking required
 190  */
 191 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
 192 {
 193         fc_fcp_pkt_release(fsp);
 194 }
 195
 196 /**
 197  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
 198  * @fsp:        fcp packet
 199  *
 200  * We should only return error if we return a command to scsi-ml before
 201  * getting a response. This can happen in cases where we send a abort, but
 202  * do not wait for the response and the abort and command can be passing
 203  * each other on the wire/network-layer.
 204  *
 205  * Note: this function locks the packet and gets a reference to allow
 206  * callers to call the completion function while the lock is held and
 207  * not have to worry about the packets refcount.
 208  *
 209  * TODO: Maybe we should just have callers grab/release the lock and
 210  * have a function that they call to verify the fsp and grab a ref if
 211  * needed.
 212  */
 213 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
 214 {
 215         spin_lock_bh(&fsp->scsi_pkt_lock);
 216         if (fsp->state & FC_SRB_COMPL) {
 217                 spin_unlock_bh(&fsp->scsi_pkt_lock);
 218                 return -EPERM;
 219         }
 220
 221         fc_fcp_pkt_hold(fsp);
 222         return 0;
 223 }
 224
 225 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
 226 {
 227         spin_unlock_bh(&fsp->scsi_pkt_lock);
 228         fc_fcp_pkt_release(fsp);
 229 }
 230
 231 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
 232 {
 233         if (!(fsp->state & FC_SRB_COMPL))
 234                 mod_timer(&fsp->timer, jiffies + delay);
 235 }
 236
 237 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 238 {
 239         if (!fsp->seq_ptr)
 240                 return -EINVAL;
 241
 242         fsp->state |= FC_SRB_ABORT_PENDING;
 243         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 244 }
 245
 246 /*
 247  * Retry command.
 248  * An abort isn't needed.
 249  */
 250 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
 251 {
 252         if (fsp->seq_ptr) {
 253                 fsp->lp->tt.exch_done(fsp->seq_ptr);
 254                 fsp->seq_ptr = NULL;
 255         }
 256
 257         fsp->state &= ~FC_SRB_ABORT_PENDING;
 258         fsp->io_status = 0;
 259         fsp->status_code = FC_ERROR;
 260         fc_fcp_complete_locked(fsp);
 261 }
 262
 263 /*
 264  * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
 265  * transfer for a read I/O indicated by the fc_fcp_pkt.
 266  * @fsp: ptr to the fc_fcp_pkt
 267  *
 268  * This is called in exch_seq_send() when we have a newly allocated
 269  * exchange with a valid exchange id to setup ddp.
 270  *
 271  * returns: none
 272  */
 273 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
 274 {
 275         struct fc_lport *lp;
 276
 277         if (!fsp)
 278                 return;
 279
 280         lp = fsp->lp;
 281         if ((fsp->req_flags & FC_SRB_READ) &&
 282             (lp->lro_enabled) && (lp->tt.ddp_setup)) {
 283                 if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
 284                                      scsi_sg_count(fsp->cmd)))
 285                         fsp->xfer_ddp = xid;
 286         }
 287 }
 288 EXPORT_SYMBOL(fc_fcp_ddp_setup);
 289
 290 /*
 291  * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
 292  * DDP related resources for this I/O if it is initialized
 293  * as a ddp transfer
 294  * @fsp: ptr to the fc_fcp_pkt
 295  *
 296  * returns: none
 297  */
 298 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
 299 {
 300         struct fc_lport *lp;
 301
 302         if (!fsp)
 303                 return;
 304
 305         if (fsp->xfer_ddp == FC_XID_UNKNOWN)
 306                 return;
 307
 308         lp = fsp->lp;
 309         if (lp->tt.ddp_done) {
 310                 fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
 311                 fsp->xfer_ddp = FC_XID_UNKNOWN;
 312         }
 313 }
 314
 315
 316 /*
 317  * Receive SCSI data from target.
 318  * Called after receiving solicited data.
 319  */
 320 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 321 {
 322         struct scsi_cmnd *sc = fsp->cmd;
 323         struct fc_lport *lp = fsp->lp;
 324         struct fcoe_dev_stats *stats;
 325         struct fc_frame_header *fh;
 326         size_t start_offset;
 327         size_t offset;
 328         u32 crc;
 329         u32 copy_len = 0;
 330         size_t len;
 331         void *buf;
 332         struct scatterlist *sg;
 333         size_t remaining;
 334
 335         fh = fc_frame_header_get(fp);
 336         offset = ntohl(fh->fh_parm_offset);
 337         start_offset = offset;
 338         len = fr_len(fp) - sizeof(*fh);
 339         buf = fc_frame_payload_get(fp, 0);
 340
 341         /* if this I/O is ddped, update xfer len */
 342         fc_fcp_ddp_done(fsp);
 343
 344         if (offset + len > fsp->data_len) {
 345                 /* this should never happen */
 346                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
 347                     fc_frame_crc_check(fp))
 348                         goto crc_err;
 349                 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
 350                            "data_len %x\n", len, offset, fsp->data_len);
 351                 fc_fcp_retry_cmd(fsp);
 352                 return;
 353         }
 354         if (offset != fsp->xfer_len)
 355                 fsp->state |= FC_SRB_DISCONTIG;
 356
 357         crc = 0;
 358         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 359                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
 360
 361         sg = scsi_sglist(sc);
 362         remaining = len;
 363
 364         while (remaining > 0 && sg) {
 365                 size_t off;
 366                 void *page_addr;
 367                 size_t sg_bytes;
 368
 369                 if (offset >= sg->length) {
 370                         offset -= sg->length;
 371                         sg = sg_next(sg);
 372                         continue;
 373                 }
 374                 sg_bytes = min(remaining, sg->length - offset);
 375
 376                 /*
 377                  * The scatterlist item may be bigger than PAGE_SIZE,
 378                  * but we are limited to mapping PAGE_SIZE at a time.
 379                  */
 380                 off = offset + sg->offset;
 381                 sg_bytes = min(sg_bytes, (size_t)
 382                                (PAGE_SIZE - (off & ~PAGE_MASK)));
 383                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
 384                                         KM_SOFTIRQ0);
 385                 if (!page_addr)
 386                         break;          /* XXX panic? */
 387
 388                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 389                         crc = crc32(crc, buf, sg_bytes);
 390                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
 391                        sg_bytes);
 392
 393                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
 394                 buf += sg_bytes;
 395                 offset += sg_bytes;
 396                 remaining -= sg_bytes;
 397                 copy_len += sg_bytes;
 398         }
 399
 400         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
 401                 buf = fc_frame_payload_get(fp, 0);
 402                 if (len % 4) {
 403                         crc = crc32(crc, buf + len, 4 - (len % 4));
 404                         len += 4 - (len % 4);
 405                 }
 406
 407                 if (~crc != le32_to_cpu(fr_crc(fp))) {
 408 crc_err:
 409                         stats = fc_lport_get_stats(lp);
 410                         stats->ErrorFrames++;
 411                         /* FIXME - per cpu count, not total count! */
 412                         if (stats->InvalidCRCCount++ < 5)
 413                                 printk(KERN_WARNING "libfc: CRC error on data "
 414                                        "frame for port (%6x)\n",
 415                                        fc_host_port_id(lp->host));
 416                         /*
 417                          * Assume the frame is total garbage.
 418                          * We may have copied it over the good part
 419                          * of the buffer.
 420                          * If so, we need to retry the entire operation.
 421                          * Otherwise, ignore it.
 422                          */
 423                         if (fsp->state & FC_SRB_DISCONTIG)
 424                                 fc_fcp_retry_cmd(fsp);
 425                         return;
 426                 }
 427         }
 428
 429         if (fsp->xfer_contig_end == start_offset)
 430                 fsp->xfer_contig_end += copy_len;
 431         fsp->xfer_len += copy_len;
 432
 433         /*
 434          * In the very rare event that this data arrived after the response
 435          * and completes the transfer, call the completion handler.
 436          */
 437         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
 438             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
 439                 fc_fcp_complete_locked(fsp);
 440 }
 441
 442 /**
 443  * fc_fcp_send_data() -  Send SCSI data to target.
 444  * @fsp: ptr to fc_fcp_pkt
 445  * @sp: ptr to this sequence
 446  * @offset: starting offset for this data request
 447  * @seq_blen: the burst length for this data request
 448  *
 449  * Called after receiving a Transfer Ready data descriptor.
 450  * if LLD is capable of seq offload then send down seq_blen
 451  * size of data in single frame, otherwise send multiple FC
 452  * frames of max FC frame payload supported by target port.
 453  *
 454  * Returns : 0 for success.
 455  */
 456 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
 457                             size_t offset, size_t seq_blen)
 458 {
 459         struct fc_exch *ep;
 460         struct scsi_cmnd *sc;
 461         struct scatterlist *sg;
 462         struct fc_frame *fp = NULL;
 463         struct fc_lport *lp = fsp->lp;
 464         size_t remaining;
 465         size_t t_blen;
 466         size_t tlen;
 467         size_t sg_bytes;
 468         size_t frame_offset, fh_parm_offset;
 469         int error;
 470         void *data = NULL;
 471         void *page_addr;
 472         int using_sg = lp->sg_supp;
 473         u32 f_ctl;
 474
 475         WARN_ON(seq_blen <= 0);
 476         if (unlikely(offset + seq_blen > fsp->data_len)) {
 477                 /* this should never happen */
 478                 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
 479                            "offset %zx\n", seq_blen, offset);
 480                 fc_fcp_send_abort(fsp);
 481                 return 0;
 482         } else if (offset != fsp->xfer_len) {
 483                 /* Out of Order Data Request - no problem, but unexpected. */
 484                 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
 485                            "seq_blen %zx offset %zx\n", seq_blen, offset);
 486         }
 487
 488         /*
 489          * if LLD is capable of seq_offload then set transport
 490          * burst length (t_blen) to seq_blen, otherwise set t_blen
 491          * to max FC frame payload previously set in fsp->max_payload.
 492          */
 493         t_blen = fsp->max_payload;
 494         if (lp->seq_offload) {
 495                 t_blen = min(seq_blen, (size_t)lp->lso_max);
 496                 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
 497                            fsp, seq_blen, lp->lso_max, t_blen);
 498         }
 499
 500         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
 501         if (t_blen > 512)
 502                 t_blen &= ~(512 - 1);   /* round down to block size */
 503         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
 504         sc = fsp->cmd;
 505
 506         remaining = seq_blen;
 507         fh_parm_offset = frame_offset = offset;
 508         tlen = 0;
 509         seq = lp->tt.seq_start_next(seq);
 510         f_ctl = FC_FC_REL_OFF;
 511         WARN_ON(!seq);
 512
 513         sg = scsi_sglist(sc);
 514
 515         while (remaining > 0 && sg) {
 516                 if (offset >= sg->length) {
 517                         offset -= sg->length;
 518                         sg = sg_next(sg);
 519                         continue;
 520                 }
 521                 if (!fp) {
 522                         tlen = min(t_blen, remaining);
 523
 524                         /*
 525                          * TODO.  Temporary workaround.  fc_seq_send() can't
 526                          * handle odd lengths in non-linear skbs.
 527                          * This will be the final fragment only.
 528                          */
 529                         if (tlen % 4)
 530                                 using_sg = 0;
 531                         if (using_sg) {
 532                                 fp = _fc_frame_alloc(lp, 0);
 533                                 if (!fp)
 534                                         return -ENOMEM;
 535                         } else {
 536                                 fp = fc_frame_alloc(lp, tlen);
 537                                 if (!fp)
 538                                         return -ENOMEM;
 539
 540                                 data = (void *)(fr_hdr(fp)) +
 541                                         sizeof(struct fc_frame_header);
 542                         }
 543                         fh_parm_offset = frame_offset;
 544                         fr_max_payload(fp) = fsp->max_payload;
 545                 }
 546                 sg_bytes = min(tlen, sg->length - offset);
 547                 if (using_sg) {
 548                         get_page(sg_page(sg));
 549                         skb_fill_page_desc(fp_skb(fp),
 550                                            skb_shinfo(fp_skb(fp))->nr_frags,
 551                                            sg_page(sg), sg->offset + offset,
 552                                            sg_bytes);
 553                         fp_skb(fp)->data_len += sg_bytes;
 554                         fr_len(fp) += sg_bytes;
 555                         fp_skb(fp)->truesize += PAGE_SIZE;
 556                 } else {
 557                         size_t off = offset + sg->offset;
 558
 559                         /*
 560                          * The scatterlist item may be bigger than PAGE_SIZE,
 561                          * but we must not cross pages inside the kmap.
 562                          */
 563                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
 564                                                            (off & ~PAGE_MASK)));
 565                         page_addr = kmap_atomic(sg_page(sg) +
 566                                                 (off >> PAGE_SHIFT),
 567                                                 KM_SOFTIRQ0);
 568                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
 569                                sg_bytes);
 570                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
 571                         data += sg_bytes;
 572                 }
 573                 offset += sg_bytes;
 574                 frame_offset += sg_bytes;
 575                 tlen -= sg_bytes;
 576                 remaining -= sg_bytes;
 577
 578                 if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
 579                     (tlen))
 580                         continue;
 581
 582                 /*
 583                  * Send sequence with transfer sequence initiative in case
 584                  * this is last FCP frame of the sequence.
 585                  */
 586                 if (remaining == 0)
 587                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
 588
 589                 ep = fc_seq_exch(seq);
 590                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
 591                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
 592
 593                 /*
 594                  * send fragment using for a sequence.
 595                  */
 596                 error = lp->tt.seq_send(lp, seq, fp);
 597                 if (error) {
 598                         WARN_ON(1);             /* send error should be rare */
 599                         fc_fcp_retry_cmd(fsp);
 600                         return 0;
 601                 }
 602                 fp = NULL;
 603         }
 604         fsp->xfer_len += seq_blen;      /* premature count? */
 605         return 0;
 606 }
 607
 608 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 609 {
 610         int ba_done = 1;
 611         struct fc_ba_rjt *brp;
 612         struct fc_frame_header *fh;
 613
 614         fh = fc_frame_header_get(fp);
 615         switch (fh->fh_r_ctl) {
 616         case FC_RCTL_BA_ACC:
 617                 break;
 618         case FC_RCTL_BA_RJT:
 619                 brp = fc_frame_payload_get(fp, sizeof(*brp));
 620                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
 621                         break;
 622                 /* fall thru */
 623         default:
 624                 /*
 625                  * we will let the command timeout
 626                  * and scsi-ml recover in this case,
 627                  * therefore cleared the ba_done flag.
 628                  */
 629                 ba_done = 0;
 630         }
 631
 632         if (ba_done) {
 633                 fsp->state |= FC_SRB_ABORTED;
 634                 fsp->state &= ~FC_SRB_ABORT_PENDING;
 635
 636                 if (fsp->wait_for_comp)
 637                         complete(&fsp->tm_done);
 638                 else
 639                         fc_fcp_complete_locked(fsp);
 640         }
 641 }
 642
 643 /**
 644  * fc_fcp_reduce_can_queue() - drop can_queue
 645  * @lp: lport to drop queueing for
 646  *
 647  * If we are getting memory allocation failures, then we may
 648  * be trying to execute too many commands. We let the running
 649  * commands complete or timeout, then try again with a reduced
 650  * can_queue. Eventually we will hit the point where we run
 651  * on all reserved structs.
 652  */
 653 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
 654 {
 655         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 656         unsigned long flags;
 657         int can_queue;
 658
 659         spin_lock_irqsave(lp->host->host_lock, flags);
 660         if (si->throttled)
 661                 goto done;
 662         si->throttled = 1;
 663
 664         can_queue = lp->host->can_queue;
 665         can_queue >>= 1;
 666         if (!can_queue)
 667                 can_queue = 1;
 668         lp->host->can_queue = can_queue;
 669         shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n"
 670                      "Reducing can_queue to %d.\n", can_queue);
 671 done:
 672         spin_unlock_irqrestore(lp->host->host_lock, flags);
 673 }
 674
 675 /**
 676  * fc_fcp_recv() - Reveive FCP frames
 677  * @seq: The sequence the frame is on
 678  * @fp: The FC frame
 679  * @arg: The related FCP packet
 680  *
 681  * Return   : None
 682  * Context  : called from Soft IRQ context
 683  *            can not called holding list lock
 684  */
 685 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 686 {
 687         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
 688         struct fc_lport *lport = fsp->lp;
 689         struct fc_frame_header *fh;
 690         struct fcp_txrdy *dd;
 691         u8 r_ctl;
 692         int rc = 0;
 693
 694         if (IS_ERR(fp))
 695                 goto errout;
 696
 697         fh = fc_frame_header_get(fp);
 698         r_ctl = fh->fh_r_ctl;
 699
 700         if (!(lport->state & LPORT_ST_READY))
 701                 goto out;
 702         if (fc_fcp_lock_pkt(fsp))
 703                 goto out;
 704         fsp->last_pkt_time = jiffies;
 705
 706         if (fh->fh_type == FC_TYPE_BLS) {
 707                 fc_fcp_abts_resp(fsp, fp);
 708                 goto unlock;
 709         }
 710
 711         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
 712                 goto unlock;
 713
 714         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
 715                 /*
 716                  * received XFER RDY from the target
 717                  * need to send data to the target
 718                  */
 719                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 720                 dd = fc_frame_payload_get(fp, sizeof(*dd));
 721                 WARN_ON(!dd);
 722
 723                 rc = fc_fcp_send_data(fsp, seq,
 724                                       (size_t) ntohl(dd->ft_data_ro),
 725                                       (size_t) ntohl(dd->ft_burst_len));
 726                 if (!rc)
 727                         seq->rec_data = fsp->xfer_len;
 728                 else if (rc == -ENOMEM)
 729                         fsp->state |= FC_SRB_NOMEM;
 730         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
 731                 /*
 732                  * received a DATA frame
 733                  * next we will copy the data to the system buffer
 734                  */
 735                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
 736                 fc_fcp_recv_data(fsp, fp);
 737                 seq->rec_data = fsp->xfer_contig_end;
 738         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
 739                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 740
 741                 fc_fcp_resp(fsp, fp);
 742         } else {
 743                 FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
 744         }
 745 unlock:
 746         fc_fcp_unlock_pkt(fsp);
 747 out:
 748         fc_frame_free(fp);
 749 errout:
 750         if (IS_ERR(fp))
 751                 fc_fcp_error(fsp, fp);
 752         else if (rc == -ENOMEM)
 753                 fc_fcp_reduce_can_queue(lport);
 754 }
 755
 756 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 757 {
 758         struct fc_frame_header *fh;
 759         struct fcp_resp *fc_rp;
 760         struct fcp_resp_ext *rp_ex;
 761         struct fcp_resp_rsp_info *fc_rp_info;
 762         u32 plen;
 763         u32 expected_len;
 764         u32 respl = 0;
 765         u32 snsl = 0;
 766         u8 flags = 0;
 767
 768         plen = fr_len(fp);
 769         fh = (struct fc_frame_header *)fr_hdr(fp);
 770         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
 771                 goto len_err;
 772         plen -= sizeof(*fh);
 773         fc_rp = (struct fcp_resp *)(fh + 1);
 774         fsp->cdb_status = fc_rp->fr_status;
 775         flags = fc_rp->fr_flags;
 776         fsp->scsi_comp_flags = flags;
 777         expected_len = fsp->data_len;
 778
 779         /* if ddp, update xfer len */
 780         fc_fcp_ddp_done(fsp);
 781
 782         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
 783                 rp_ex = (void *)(fc_rp + 1);
 784                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
 785                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
 786                                 goto len_err;
 787                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
 788                         if (flags & FCP_RSP_LEN_VAL) {
 789                                 respl = ntohl(rp_ex->fr_rsp_len);
 790                                 if (respl != sizeof(*fc_rp_info))
 791                                         goto len_err;
 792                                 if (fsp->wait_for_comp) {
 793                                         /* Abuse cdb_status for rsp code */
 794                                         fsp->cdb_status = fc_rp_info->rsp_code;
 795                                         complete(&fsp->tm_done);
 796                                         /*
 797                                          * tmfs will not have any scsi cmd so
 798                                          * exit here
 799                                          */
 800                                         return;
 801                                 } else
 802                                         goto err;
 803                         }
 804                         if (flags & FCP_SNS_LEN_VAL) {
 805                                 snsl = ntohl(rp_ex->fr_sns_len);
 806                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
 807                                         snsl = SCSI_SENSE_BUFFERSIZE;
 808                                 memcpy(fsp->cmd->sense_buffer,
 809                                        (char *)fc_rp_info + respl, snsl);
 810                         }
 811                 }
 812                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
 813                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
 814                                 goto len_err;
 815                         if (flags & FCP_RESID_UNDER) {
 816                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
 817                                 /*
 818                                  * The cmnd->underflow is the minimum number of
 819                                  * bytes that must be transfered for this
 820                                  * command.  Provided a sense condition is not
 821                                  * present, make sure the actual amount
 822                                  * transferred is at least the underflow value
 823                                  * or fail.
 824                                  */
 825                                 if (!(flags & FCP_SNS_LEN_VAL) &&
 826                                     (fc_rp->fr_status == 0) &&
 827                                     (scsi_bufflen(fsp->cmd) -
 828                                      fsp->scsi_resid) < fsp->cmd->underflow)
 829                                         goto err;
 830                                 expected_len -= fsp->scsi_resid;
 831                         } else {
 832                                 fsp->status_code = FC_ERROR;
 833                         }
 834                 }
 835         }
 836         fsp->state |= FC_SRB_RCV_STATUS;
 837
 838         /*
 839          * Check for missing or extra data frames.
 840          */
 841         if (unlikely(fsp->xfer_len != expected_len)) {
 842                 if (fsp->xfer_len < expected_len) {
 843                         /*
 844                          * Some data may be queued locally,
 845                          * Wait a at least one jiffy to see if it is delivered.
 846                          * If this expires without data, we may do SRR.
 847                          */
 848                         fc_fcp_timer_set(fsp, 2);
 849                         return;
 850                 }
 851                 fsp->status_code = FC_DATA_OVRRUN;
 852                 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
 853                            "len %x, data len %x\n",
 854                            fsp->rport->port_id,
 855                            fsp->xfer_len, expected_len, fsp->data_len);
 856         }
 857         fc_fcp_complete_locked(fsp);
 858         return;
 859
 860 len_err:
 861         FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
 862                    "snsl %u\n", flags, fr_len(fp), respl, snsl);
 863 err:
 864         fsp->status_code = FC_ERROR;
 865         fc_fcp_complete_locked(fsp);
 866 }
 867
 868 /**
 869  * fc_fcp_complete_locked() - complete processing of a fcp packet
 870  * @fsp:        fcp packet
 871  *
 872  * This function may sleep if a timer is pending. The packet lock must be
 873  * held, and the host lock must not be held.
 874  */
 875 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
 876 {
 877         struct fc_lport *lp = fsp->lp;
 878         struct fc_seq *seq;
 879         struct fc_exch *ep;
 880         u32 f_ctl;
 881
 882         if (fsp->state & FC_SRB_ABORT_PENDING)
 883                 return;
 884
 885         if (fsp->state & FC_SRB_ABORTED) {
 886                 if (!fsp->status_code)
 887                         fsp->status_code = FC_CMD_ABORTED;
 888         } else {
 889                 /*
 890                  * Test for transport underrun, independent of response
 891                  * underrun status.
 892                  */
 893                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
 894                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
 895                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
 896                         fsp->status_code = FC_DATA_UNDRUN;
 897                         fsp->io_status = 0;
 898                 }
 899         }
 900
 901         seq = fsp->seq_ptr;
 902         if (seq) {
 903                 fsp->seq_ptr = NULL;
 904                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
 905                         struct fc_frame *conf_frame;
 906                         struct fc_seq *csp;
 907
 908                         csp = lp->tt.seq_start_next(seq);
 909                         conf_frame = fc_frame_alloc(fsp->lp, 0);
 910                         if (conf_frame) {
 911                                 f_ctl = FC_FC_SEQ_INIT;
 912                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
 913                                 ep = fc_seq_exch(seq);
 914                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
 915                                                ep->did, ep->sid,
 916                                                FC_TYPE_FCP, f_ctl, 0);
 917                                 lp->tt.seq_send(lp, csp, conf_frame);
 918                         }
 919                 }
 920                 lp->tt.exch_done(seq);
 921         }
 922         fc_io_compl(fsp);
 923 }
 924
 925 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
 926 {
 927         struct fc_lport *lp = fsp->lp;
 928
 929         if (fsp->seq_ptr) {
 930                 lp->tt.exch_done(fsp->seq_ptr);
 931                 fsp->seq_ptr = NULL;
 932         }
 933         fsp->status_code = error;
 934 }
 935
 936 /**
 937  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
 938  * @lp:         logical port
 939  * @id:         target id
 940  * @lun:        lun
 941  * @error:      fsp status code
 942  *
 943  * If lun or id is -1, they are ignored.
 944  */
 945 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
 946                                     unsigned int lun, int error)
 947 {
 948         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 949         struct fc_fcp_pkt *fsp;
 950         struct scsi_cmnd *sc_cmd;
 951         unsigned long flags;
 952
 953         spin_lock_irqsave(lp->host->host_lock, flags);
 954 restart:
 955         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
 956                 sc_cmd = fsp->cmd;
 957                 if (id != -1 && scmd_id(sc_cmd) != id)
 958                         continue;
 959
 960                 if (lun != -1 && sc_cmd->device->lun != lun)
 961                         continue;
 962
 963                 fc_fcp_pkt_hold(fsp);
 964                 spin_unlock_irqrestore(lp->host->host_lock, flags);
 965
 966                 if (!fc_fcp_lock_pkt(fsp)) {
 967                         fc_fcp_cleanup_cmd(fsp, error);
 968                         fc_io_compl(fsp);
 969                         fc_fcp_unlock_pkt(fsp);
 970                 }
 971
 972                 fc_fcp_pkt_release(fsp);
 973                 spin_lock_irqsave(lp->host->host_lock, flags);
 974                 /*
 975                  * while we dropped the lock multiple pkts could
 976                  * have been released, so we have to start over.
 977                  */
 978                 goto restart;
 979         }
 980         spin_unlock_irqrestore(lp->host->host_lock, flags);
 981 }
 982
 983 static void fc_fcp_abort_io(struct fc_lport *lp)
 984 {
 985         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
 986 }
 987
 988 /**
 989  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
 990  * @lp:         fc lport
 991  * @fsp:        fc packet.
 992  *
 993  * This is called by upper layer protocol.
 994  * Return   : zero for success and -1 for failure
 995  * Context  : called from queuecommand which can be called from process
 996  *            or scsi soft irq.
 997  * Locks    : called with the host lock and irqs disabled.
 998  */
 999 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1000 {
1001         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
1002         int rc;
1003
1004         fsp->cmd->SCp.ptr = (char *)fsp;
1005         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1006         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1007
1008         int_to_scsilun(fsp->cmd->device->lun,
1009                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1010         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1011         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1012
1013         spin_unlock_irq(lp->host->host_lock);
1014         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
1015         spin_lock_irq(lp->host->host_lock);
1016         if (rc)
1017                 list_del(&fsp->list);
1018
1019         return rc;
1020 }
1021
1022 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1023                            void (*resp)(struct fc_seq *,
1024                                         struct fc_frame *fp,
1025                                         void *arg))
1026 {
1027         struct fc_frame *fp;
1028         struct fc_seq *seq;
1029         struct fc_rport *rport;
1030         struct fc_rport_libfc_priv *rp;
1031         const size_t len = sizeof(fsp->cdb_cmd);
1032         int rc = 0;
1033
1034         if (fc_fcp_lock_pkt(fsp))
1035                 return 0;
1036
1037         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1038         if (!fp) {
1039                 rc = -1;
1040                 goto unlock;
1041         }
1042
1043         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1044         fr_fsp(fp) = fsp;
1045         rport = fsp->rport;
1046         fsp->max_payload = rport->maxframe_size;
1047         rp = rport->dd_data;
1048
1049         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1050                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1051                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1052
1053         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1054         if (!seq) {
1055                 rc = -1;
1056                 goto unlock;
1057         }
1058         fsp->last_pkt_time = jiffies;
1059         fsp->seq_ptr = seq;
1060         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1061
1062         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1063         fc_fcp_timer_set(fsp,
1064                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1065                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1066 unlock:
1067         fc_fcp_unlock_pkt(fsp);
1068         return rc;
1069 }
1070
1071 /*
1072  * transport error handler
1073  */
1074 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1075 {
1076         int error = PTR_ERR(fp);
1077
1078         if (fc_fcp_lock_pkt(fsp))
1079                 return;
1080
1081         if (error == -FC_EX_CLOSED) {
1082                 fc_fcp_retry_cmd(fsp);
1083                 goto unlock;
1084         }
1085
1086         /*
1087          * clear abort pending, because the lower layer
1088          * decided to force completion.
1089          */
1090         fsp->state &= ~FC_SRB_ABORT_PENDING;
1091         fsp->status_code = FC_CMD_PLOGO;
1092         fc_fcp_complete_locked(fsp);
1093 unlock:
1094         fc_fcp_unlock_pkt(fsp);
1095 }
1096
1097 /*
1098  * Scsi abort handler- calls to send an abort
1099  * and then wait for abort completion
1100  */
1101 static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1102 {
1103         int rc = FAILED;
1104
1105         if (fc_fcp_send_abort(fsp))
1106                 return FAILED;
1107
1108         init_completion(&fsp->tm_done);
1109         fsp->wait_for_comp = 1;
1110
1111         spin_unlock_bh(&fsp->scsi_pkt_lock);
1112         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1113         spin_lock_bh(&fsp->scsi_pkt_lock);
1114         fsp->wait_for_comp = 0;
1115
1116         if (!rc) {
1117                 FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1118                 rc = FAILED;
1119         } else if (fsp->state & FC_SRB_ABORTED) {
1120                 FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1121                 rc = SUCCESS;
1122                 fc_fcp_complete_locked(fsp);
1123         }
1124
1125         return rc;
1126 }
1127
1128 /*
1129  * Retry LUN reset after resource allocation failed.
1130  */
1131 static void fc_lun_reset_send(unsigned long data)
1132 {
1133         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1134         struct fc_lport *lp = fsp->lp;
1135         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1136                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1137                         return;
1138                 if (fc_fcp_lock_pkt(fsp))
1139                         return;
1140                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1141                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1142                 fc_fcp_unlock_pkt(fsp);
1143         }
1144 }
1145
1146 /*
1147  * Scsi device reset handler- send a LUN RESET to the device
1148  * and wait for reset reply
1149  */
1150 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1151                         unsigned int id, unsigned int lun)
1152 {
1153         int rc;
1154
1155         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1156         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1157         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1158
1159         fsp->wait_for_comp = 1;
1160         init_completion(&fsp->tm_done);
1161
1162         fc_lun_reset_send((unsigned long)fsp);
1163
1164         /*
1165          * wait for completion of reset
1166          * after that make sure all commands are terminated
1167          */
1168         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1169
1170         spin_lock_bh(&fsp->scsi_pkt_lock);
1171         fsp->state |= FC_SRB_COMPL;
1172         spin_unlock_bh(&fsp->scsi_pkt_lock);
1173
1174         del_timer_sync(&fsp->timer);
1175
1176         spin_lock_bh(&fsp->scsi_pkt_lock);
1177         if (fsp->seq_ptr) {
1178                 lp->tt.exch_done(fsp->seq_ptr);
1179                 fsp->seq_ptr = NULL;
1180         }
1181         fsp->wait_for_comp = 0;
1182         spin_unlock_bh(&fsp->scsi_pkt_lock);
1183
1184         if (!rc) {
1185                 FC_SCSI_DBG(lp, "lun reset failed\n");
1186                 return FAILED;
1187         }
1188
1189         /* cdb_status holds the tmf's rsp code */
1190         if (fsp->cdb_status != FCP_TMF_CMPL)
1191                 return FAILED;
1192
1193         FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun);
1194         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1195         return SUCCESS;
1196 }
1197
1198 /*
1199  * Task Managment response handler
1200  */
1201 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1202 {
1203         struct fc_fcp_pkt *fsp = arg;
1204         struct fc_frame_header *fh;
1205
1206         if (IS_ERR(fp)) {
1207                 /*
1208                  * If there is an error just let it timeout or wait
1209                  * for TMF to be aborted if it timedout.
1210                  *
1211                  * scsi-eh will escalate for when either happens.
1212                  */
1213                 return;
1214         }
1215
1216         if (fc_fcp_lock_pkt(fsp))
1217                 return;
1218
1219         /*
1220          * raced with eh timeout handler.
1221          */
1222         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1223                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1224                 return;
1225         }
1226
1227         fh = fc_frame_header_get(fp);
1228         if (fh->fh_type != FC_TYPE_BLS)
1229                 fc_fcp_resp(fsp, fp);
1230         fsp->seq_ptr = NULL;
1231         fsp->lp->tt.exch_done(seq);
1232         fc_frame_free(fp);
1233         fc_fcp_unlock_pkt(fsp);
1234 }
1235
1236 static void fc_fcp_cleanup(struct fc_lport *lp)
1237 {
1238         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1239 }
1240
1241 /*
1242  * fc_fcp_timeout: called by OS timer function.
1243  *
1244  * The timer has been inactivated and must be reactivated if desired
1245  * using fc_fcp_timer_set().
1246  *
1247  * Algorithm:
1248  *
1249  * If REC is supported, just issue it, and return.  The REC exchange will
1250  * complete or time out, and recovery can continue at that point.
1251  *
1252  * Otherwise, if the response has been received without all the data,
1253  * it has been ER_TIMEOUT since the response was received.
1254  *
1255  * If the response has not been received,
1256  * we see if data was received recently.  If it has been, we continue waiting,
1257  * otherwise, we abort the command.
1258  */
1259 static void fc_fcp_timeout(unsigned long data)
1260 {
1261         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1262         struct fc_rport *rport = fsp->rport;
1263         struct fc_rport_libfc_priv *rp = rport->dd_data;
1264
1265         if (fc_fcp_lock_pkt(fsp))
1266                 return;
1267
1268         if (fsp->cdb_cmd.fc_tm_flags)
1269                 goto unlock;
1270
1271         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1272
1273         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1274                 fc_fcp_rec(fsp);
1275         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1276                                jiffies))
1277                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1278         else if (fsp->state & FC_SRB_RCV_STATUS)
1279                 fc_fcp_complete_locked(fsp);
1280         else
1281                 fc_timeout_error(fsp);
1282         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1283 unlock:
1284         fc_fcp_unlock_pkt(fsp);
1285 }
1286
1287 /*
1288  * Send a REC ELS request
1289  */
1290 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1291 {
1292         struct fc_lport *lp;
1293         struct fc_frame *fp;
1294         struct fc_rport *rport;
1295         struct fc_rport_libfc_priv *rp;
1296
1297         lp = fsp->lp;
1298         rport = fsp->rport;
1299         rp = rport->dd_data;
1300         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1301                 fsp->status_code = FC_HRD_ERROR;
1302                 fsp->io_status = 0;
1303                 fc_fcp_complete_locked(fsp);
1304                 return;
1305         }
1306         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1307         if (!fp)
1308                 goto retry;
1309
1310         fr_seq(fp) = fsp->seq_ptr;
1311         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1312                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1313                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1314         if (lp->tt.elsct_send(lp, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp,
1315                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1316                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1317                 return;
1318         }
1319 retry:
1320         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1321                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1322         else
1323                 fc_timeout_error(fsp);
1324 }
1325
1326 /*
1327  * Receive handler for REC ELS frame
1328  * if it is a reject then let the scsi layer to handle
1329  * the timeout. if it is a LS_ACC then if the io was not completed
1330  * then set the timeout and return otherwise complete the exchange
1331  * and tell the scsi layer to restart the I/O.
1332  */
1333 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1334 {
1335         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1336         struct fc_els_rec_acc *recp;
1337         struct fc_els_ls_rjt *rjt;
1338         u32 e_stat;
1339         u8 opcode;
1340         u32 offset;
1341         enum dma_data_direction data_dir;
1342         enum fc_rctl r_ctl;
1343         struct fc_rport_libfc_priv *rp;
1344
1345         if (IS_ERR(fp)) {
1346                 fc_fcp_rec_error(fsp, fp);
1347                 return;
1348         }
1349
1350         if (fc_fcp_lock_pkt(fsp))
1351                 goto out;
1352
1353         fsp->recov_retry = 0;
1354         opcode = fc_frame_payload_op(fp);
1355         if (opcode == ELS_LS_RJT) {
1356                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1357                 switch (rjt->er_reason) {
1358                 default:
1359                         FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1360                                    "reason %d expl %d\n",
1361                                    fsp->rport->port_id, rjt->er_reason,
1362                                    rjt->er_explan);
1363                         /* fall through */
1364                 case ELS_RJT_UNSUP:
1365                         FC_FCP_DBG(fsp, "device does not support REC\n");
1366                         rp = fsp->rport->dd_data;
1367                         /*
1368                          * if we do not spport RECs or got some bogus
1369                          * reason then resetup timer so we check for
1370                          * making progress.
1371                          */
1372                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1373                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1374                         break;
1375                 case ELS_RJT_LOGIC:
1376                 case ELS_RJT_UNAB:
1377                         /*
1378                          * If no data transfer, the command frame got dropped
1379                          * so we just retry.  If data was transferred, we
1380                          * lost the response but the target has no record,
1381                          * so we abort and retry.
1382                          */
1383                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1384                             fsp->xfer_len == 0) {
1385                                 fc_fcp_retry_cmd(fsp);
1386                                 break;
1387                         }
1388                         fc_timeout_error(fsp);
1389                         break;
1390                 }
1391         } else if (opcode == ELS_LS_ACC) {
1392                 if (fsp->state & FC_SRB_ABORTED)
1393                         goto unlock_out;
1394
1395                 data_dir = fsp->cmd->sc_data_direction;
1396                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1397                 offset = ntohl(recp->reca_fc4value);
1398                 e_stat = ntohl(recp->reca_e_stat);
1399
1400                 if (e_stat & ESB_ST_COMPLETE) {
1401
1402                         /*
1403                          * The exchange is complete.
1404                          *
1405                          * For output, we must've lost the response.
1406                          * For input, all data must've been sent.
1407                          * We lost may have lost the response
1408                          * (and a confirmation was requested) and maybe
1409                          * some data.
1410                          *
1411                          * If all data received, send SRR
1412                          * asking for response.  If partial data received,
1413                          * or gaps, SRR requests data at start of gap.
1414                          * Recovery via SRR relies on in-order-delivery.
1415                          */
1416                         if (data_dir == DMA_TO_DEVICE) {
1417                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1418                         } else if (fsp->xfer_contig_end == offset) {
1419                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1420                         } else {
1421                                 offset = fsp->xfer_contig_end;
1422                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1423                         }
1424                         fc_fcp_srr(fsp, r_ctl, offset);
1425                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1426
1427                         /*
1428                          * The remote port has the initiative, so just
1429                          * keep waiting for it to complete.
1430                          */
1431                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1432                 } else {
1433
1434                         /*
1435                          * The exchange is incomplete, we have seq. initiative.
1436                          * Lost response with requested confirmation,
1437                          * lost confirmation, lost transfer ready or
1438                          * lost write data.
1439                          *
1440                          * For output, if not all data was received, ask
1441                          * for transfer ready to be repeated.
1442                          *
1443                          * If we received or sent all the data, send SRR to
1444                          * request response.
1445                          *
1446                          * If we lost a response, we may have lost some read
1447                          * data as well.
1448                          */
1449                         r_ctl = FC_RCTL_DD_SOL_DATA;
1450                         if (data_dir == DMA_TO_DEVICE) {
1451                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1452                                 if (offset < fsp->data_len)
1453                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1454                         } else if (offset == fsp->xfer_contig_end) {
1455                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1456                         } else if (fsp->xfer_contig_end < offset) {
1457                                 offset = fsp->xfer_contig_end;
1458                         }
1459                         fc_fcp_srr(fsp, r_ctl, offset);
1460                 }
1461         }
1462 unlock_out:
1463         fc_fcp_unlock_pkt(fsp);
1464 out:
1465         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1466         fc_frame_free(fp);
1467 }
1468
1469 /*
1470  * Handle error response or timeout for REC exchange.
1471  */
1472 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1473 {
1474         int error = PTR_ERR(fp);
1475
1476         if (fc_fcp_lock_pkt(fsp))
1477                 goto out;
1478
1479         switch (error) {
1480         case -FC_EX_CLOSED:
1481                 fc_fcp_retry_cmd(fsp);
1482                 break;
1483
1484         default:
1485                 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1486                            fsp, fsp->rport->port_id, error);
1487                 fsp->status_code = FC_CMD_PLOGO;
1488                 /* fall through */
1489
1490         case -FC_EX_TIMEOUT:
1491                 /*
1492                  * Assume REC or LS_ACC was lost.
1493                  * The exchange manager will have aborted REC, so retry.
1494                  */
1495                 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1496                            fsp->rport->port_id, error, fsp->recov_retry,
1497                            FC_MAX_RECOV_RETRY);
1498                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1499                         fc_fcp_rec(fsp);
1500                 else
1501                         fc_timeout_error(fsp);
1502                 break;
1503         }
1504         fc_fcp_unlock_pkt(fsp);
1505 out:
1506         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1507 }
1508
1509 /*
1510  * Time out error routine:
1511  * abort's the I/O close the exchange and
1512  * send completion notification to scsi layer
1513  */
1514 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1515 {
1516         fsp->status_code = FC_CMD_TIME_OUT;
1517         fsp->cdb_status = 0;
1518         fsp->io_status = 0;
1519         /*
1520          * if this fails then we let the scsi command timer fire and
1521          * scsi-ml escalate.
1522          */
1523         fc_fcp_send_abort(fsp);
1524 }
1525
1526 /*
1527  * Sequence retransmission request.
1528  * This is called after receiving status but insufficient data, or
1529  * when expecting status but the request has timed out.
1530  */
1531 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1532 {
1533         struct fc_lport *lp = fsp->lp;
1534         struct fc_rport *rport;
1535         struct fc_rport_libfc_priv *rp;
1536         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1537         struct fc_seq *seq;
1538         struct fcp_srr *srr;
1539         struct fc_frame *fp;
1540         u8 cdb_op;
1541
1542         rport = fsp->rport;
1543         rp = rport->dd_data;
1544         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1545
1546         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1547                 goto retry;                     /* shouldn't happen */
1548         fp = fc_frame_alloc(lp, sizeof(*srr));
1549         if (!fp)
1550                 goto retry;
1551
1552         srr = fc_frame_payload_get(fp, sizeof(*srr));
1553         memset(srr, 0, sizeof(*srr));
1554         srr->srr_op = ELS_SRR;
1555         srr->srr_ox_id = htons(ep->oxid);
1556         srr->srr_rx_id = htons(ep->rxid);
1557         srr->srr_r_ctl = r_ctl;
1558         srr->srr_rel_off = htonl(offset);
1559
1560         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1561                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1562                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1563
1564         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1565                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1566         if (!seq)
1567                 goto retry;
1568
1569         fsp->recov_seq = seq;
1570         fsp->xfer_len = offset;
1571         fsp->xfer_contig_end = offset;
1572         fsp->state &= ~FC_SRB_RCV_STATUS;
1573         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1574         return;
1575 retry:
1576         fc_fcp_retry_cmd(fsp);
1577 }
1578
1579 /*
1580  * Handle response from SRR.
1581  */
1582 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1583 {
1584         struct fc_fcp_pkt *fsp = arg;
1585         struct fc_frame_header *fh;
1586
1587         if (IS_ERR(fp)) {
1588                 fc_fcp_srr_error(fsp, fp);
1589                 return;
1590         }
1591
1592         if (fc_fcp_lock_pkt(fsp))
1593                 goto out;
1594
1595         fh = fc_frame_header_get(fp);
1596         /*
1597          * BUG? fc_fcp_srr_error calls exch_done which would release
1598          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1599          * then fc_exch_timeout would be sending an abort. The exch_done
1600          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1601          * an abort response though.
1602          */
1603         if (fh->fh_type == FC_TYPE_BLS) {
1604                 fc_fcp_unlock_pkt(fsp);
1605                 return;
1606         }
1607
1608         fsp->recov_seq = NULL;
1609         switch (fc_frame_payload_op(fp)) {
1610         case ELS_LS_ACC:
1611                 fsp->recov_retry = 0;
1612                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1613                 break;
1614         case ELS_LS_RJT:
1615         default:
1616                 fc_timeout_error(fsp);
1617                 break;
1618         }
1619         fc_fcp_unlock_pkt(fsp);
1620         fsp->lp->tt.exch_done(seq);
1621 out:
1622         fc_frame_free(fp);
1623         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1624 }
1625
1626 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1627 {
1628         if (fc_fcp_lock_pkt(fsp))
1629                 goto out;
1630         fsp->lp->tt.exch_done(fsp->recov_seq);
1631         fsp->recov_seq = NULL;
1632         switch (PTR_ERR(fp)) {
1633         case -FC_EX_TIMEOUT:
1634                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1635                         fc_fcp_rec(fsp);
1636                 else
1637                         fc_timeout_error(fsp);
1638                 break;
1639         case -FC_EX_CLOSED:                     /* e.g., link failure */
1640                 /* fall through */
1641         default:
1642                 fc_fcp_retry_cmd(fsp);
1643                 break;
1644         }
1645         fc_fcp_unlock_pkt(fsp);
1646 out:
1647         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1648 }
1649
1650 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1651 {
1652         /* lock ? */
1653         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1654 }
1655
1656 /**
1657  * fc_queuecommand - The queuecommand function of the scsi template
1658  * @cmd:        struct scsi_cmnd to be executed
1659  * @done:       Callback function to be called when cmd is completed
1660  *
1661  * this is the i/o strategy routine, called by the scsi layer
1662  * this routine is called with holding the host_lock.
1663  */
1664 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1665 {
1666         struct fc_lport *lp;
1667         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1668         struct fc_fcp_pkt *fsp;
1669         struct fc_rport_libfc_priv *rp;
1670         int rval;
1671         int rc = 0;
1672         struct fcoe_dev_stats *stats;
1673
1674         lp = shost_priv(sc_cmd->device->host);
1675
1676         rval = fc_remote_port_chkready(rport);
1677         if (rval) {
1678                 sc_cmd->result = rval;
1679                 done(sc_cmd);
1680                 goto out;
1681         }
1682
1683         if (!*(struct fc_remote_port **)rport->dd_data) {
1684                 /*
1685                  * rport is transitioning from blocked/deleted to
1686                  * online
1687                  */
1688                 sc_cmd->result = DID_IMM_RETRY << 16;
1689                 done(sc_cmd);
1690                 goto out;
1691         }
1692
1693         rp = rport->dd_data;
1694
1695         if (!fc_fcp_lport_queue_ready(lp)) {
1696                 rc = SCSI_MLQUEUE_HOST_BUSY;
1697                 goto out;
1698         }
1699
1700         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1701         if (fsp == NULL) {
1702                 rc = SCSI_MLQUEUE_HOST_BUSY;
1703                 goto out;
1704         }
1705
1706         /*
1707          * build the libfc request pkt
1708          */
1709         fsp->cmd = sc_cmd;      /* save the cmd */
1710         fsp->lp = lp;           /* save the softc ptr */
1711         fsp->rport = rport;     /* set the remote port ptr */
1712         fsp->xfer_ddp = FC_XID_UNKNOWN;
1713         sc_cmd->scsi_done = done;
1714
1715         /*
1716          * set up the transfer length
1717          */
1718         fsp->data_len = scsi_bufflen(sc_cmd);
1719         fsp->xfer_len = 0;
1720
1721         /*
1722          * setup the data direction
1723          */
1724         stats = fc_lport_get_stats(lp);
1725         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1726                 fsp->req_flags = FC_SRB_READ;
1727                 stats->InputRequests++;
1728                 stats->InputMegabytes = fsp->data_len;
1729         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1730                 fsp->req_flags = FC_SRB_WRITE;
1731                 stats->OutputRequests++;
1732                 stats->OutputMegabytes = fsp->data_len;
1733         } else {
1734                 fsp->req_flags = 0;
1735                 stats->ControlRequests++;
1736         }
1737
1738         fsp->tgt_flags = rp->flags;
1739
1740         init_timer(&fsp->timer);
1741         fsp->timer.data = (unsigned long)fsp;
1742
1743         /*
1744          * send it to the lower layer
1745          * if we get -1 return then put the request in the pending
1746          * queue.
1747          */
1748         rval = fc_fcp_pkt_send(lp, fsp);
1749         if (rval != 0) {
1750                 fsp->state = FC_SRB_FREE;
1751                 fc_fcp_pkt_release(fsp);
1752                 rc = SCSI_MLQUEUE_HOST_BUSY;
1753         }
1754 out:
1755         return rc;
1756 }
1757 EXPORT_SYMBOL(fc_queuecommand);
1758
1759 /**
1760  * fc_io_compl() -  Handle responses for completed commands
1761  * @fsp:        scsi packet
1762  *
1763  * Translates a error to a Linux SCSI error.
1764  *
1765  * The fcp packet lock must be held when calling.
1766  */
1767 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1768 {
1769         struct fc_fcp_internal *si;
1770         struct scsi_cmnd *sc_cmd;
1771         struct fc_lport *lp;
1772         unsigned long flags;
1773
1774         /* release outstanding ddp context */
1775         fc_fcp_ddp_done(fsp);
1776
1777         fsp->state |= FC_SRB_COMPL;
1778         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1779                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1780                 del_timer_sync(&fsp->timer);
1781                 spin_lock_bh(&fsp->scsi_pkt_lock);
1782         }
1783
1784         lp = fsp->lp;
1785         si = fc_get_scsi_internal(lp);
1786         spin_lock_irqsave(lp->host->host_lock, flags);
1787         if (!fsp->cmd) {
1788                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1789                 return;
1790         }
1791
1792         /*
1793          * if a command timed out while we had to try and throttle IO
1794          * and it is now getting cleaned up, then we are about to
1795          * try again so clear the throttled flag incase we get more
1796          * time outs.
1797          */
1798         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1799                 si->throttled = 0;
1800
1801         sc_cmd = fsp->cmd;
1802         fsp->cmd = NULL;
1803
1804         if (!sc_cmd->SCp.ptr) {
1805                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1806                 return;
1807         }
1808
1809         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1810         switch (fsp->status_code) {
1811         case FC_COMPLETE:
1812                 if (fsp->cdb_status == 0) {
1813                         /*
1814                          * good I/O status
1815                          */
1816                         sc_cmd->result = DID_OK << 16;
1817                         if (fsp->scsi_resid)
1818                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1819                 } else if (fsp->cdb_status == QUEUE_FULL) {
1820                         struct scsi_device *tmp_sdev;
1821                         struct scsi_device *sdev = sc_cmd->device;
1822
1823                         shost_for_each_device(tmp_sdev, sdev->host) {
1824                                 if (tmp_sdev->id != sdev->id)
1825                                         continue;
1826
1827                                 if (tmp_sdev->queue_depth > 1) {
1828                                         scsi_track_queue_full(tmp_sdev,
1829                                                               tmp_sdev->
1830                                                               queue_depth - 1);
1831                                 }
1832                         }
1833                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1834                 } else {
1835                         /*
1836                          * transport level I/O was ok but scsi
1837                          * has non zero status
1838                          */
1839                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1840                 }
1841                 break;
1842         case FC_ERROR:
1843                 sc_cmd->result = DID_ERROR << 16;
1844                 break;
1845         case FC_DATA_UNDRUN:
1846                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1847                         /*
1848                          * scsi status is good but transport level
1849                          * underrun.
1850                          */
1851                         sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ?
1852                                           DID_OK : DID_ERROR) << 16;
1853                 } else {
1854                         /*
1855                          * scsi got underrun, this is an error
1856                          */
1857                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1858                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1859                 }
1860                 break;
1861         case FC_DATA_OVRRUN:
1862                 /*
1863                  * overrun is an error
1864                  */
1865                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1866                 break;
1867         case FC_CMD_ABORTED:
1868                 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1869                 break;
1870         case FC_CMD_TIME_OUT:
1871                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1872                 break;
1873         case FC_CMD_RESET:
1874                 sc_cmd->result = (DID_RESET << 16);
1875                 break;
1876         case FC_HRD_ERROR:
1877                 sc_cmd->result = (DID_NO_CONNECT << 16);
1878                 break;
1879         default:
1880                 sc_cmd->result = (DID_ERROR << 16);
1881                 break;
1882         }
1883
1884         list_del(&fsp->list);
1885         sc_cmd->SCp.ptr = NULL;
1886         sc_cmd->scsi_done(sc_cmd);
1887         spin_unlock_irqrestore(lp->host->host_lock, flags);
1888
1889         /* release ref from initial allocation in queue command */
1890         fc_fcp_pkt_release(fsp);
1891 }
1892
1893 /**
1894  * fc_fcp_complete() - complete processing of a fcp packet
1895  * @fsp:        fcp packet
1896  *
1897  * This function may sleep if a fsp timer is pending.
1898  * The host lock must not be held by caller.
1899  */
1900 void fc_fcp_complete(struct fc_fcp_pkt *fsp)
1901 {
1902         if (fc_fcp_lock_pkt(fsp))
1903                 return;
1904
1905         fc_fcp_complete_locked(fsp);
1906         fc_fcp_unlock_pkt(fsp);
1907 }
1908 EXPORT_SYMBOL(fc_fcp_complete);
1909
1910 /**
1911  * fc_eh_abort() - Abort a command
1912  * @sc_cmd:     scsi command to abort
1913  *
1914  * From scsi host template.
1915  * send ABTS to the target device  and wait for the response
1916  * sc_cmd is the pointer to the command to be aborted.
1917  */
1918 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1919 {
1920         struct fc_fcp_pkt *fsp;
1921         struct fc_lport *lp;
1922         int rc = FAILED;
1923         unsigned long flags;
1924
1925         lp = shost_priv(sc_cmd->device->host);
1926         if (lp->state != LPORT_ST_READY)
1927                 return rc;
1928         else if (!lp->link_up)
1929                 return rc;
1930
1931         spin_lock_irqsave(lp->host->host_lock, flags);
1932         fsp = CMD_SP(sc_cmd);
1933         if (!fsp) {
1934                 /* command completed while scsi eh was setting up */
1935                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1936                 return SUCCESS;
1937         }
1938         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1939         fc_fcp_pkt_hold(fsp);
1940         spin_unlock_irqrestore(lp->host->host_lock, flags);
1941
1942         if (fc_fcp_lock_pkt(fsp)) {
1943                 /* completed while we were waiting for timer to be deleted */
1944                 rc = SUCCESS;
1945                 goto release_pkt;
1946         }
1947
1948         rc = fc_fcp_pkt_abort(lp, fsp);
1949         fc_fcp_unlock_pkt(fsp);
1950
1951 release_pkt:
1952         fc_fcp_pkt_release(fsp);
1953         return rc;
1954 }
1955 EXPORT_SYMBOL(fc_eh_abort);
1956
1957 /**
1958  * fc_eh_device_reset() Reset a single LUN
1959  * @sc_cmd:     scsi command
1960  *
1961  * Set from scsi host template to send tm cmd to the target and wait for the
1962  * response.
1963  */
1964 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1965 {
1966         struct fc_lport *lp;
1967         struct fc_fcp_pkt *fsp;
1968         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1969         int rc = FAILED;
1970         struct fc_rport_libfc_priv *rp;
1971         int rval;
1972
1973         rval = fc_remote_port_chkready(rport);
1974         if (rval)
1975                 goto out;
1976
1977         rp = rport->dd_data;
1978         lp = shost_priv(sc_cmd->device->host);
1979
1980         if (lp->state != LPORT_ST_READY)
1981                 return rc;
1982
1983         FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id);
1984
1985         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
1986         if (fsp == NULL) {
1987                 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
1988                 sc_cmd->result = DID_NO_CONNECT << 16;
1989                 goto out;
1990         }
1991
1992         /*
1993          * Build the libfc request pkt. Do not set the scsi cmnd, because
1994          * the sc passed in is not setup for execution like when sent
1995          * through the queuecommand callout.
1996          */
1997         fsp->lp = lp;           /* save the softc ptr */
1998         fsp->rport = rport;     /* set the remote port ptr */
1999
2000         /*
2001          * flush outstanding commands
2002          */
2003         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2004         fsp->state = FC_SRB_FREE;
2005         fc_fcp_pkt_release(fsp);
2006
2007 out:
2008         return rc;
2009 }
2010 EXPORT_SYMBOL(fc_eh_device_reset);
2011
2012 /**
2013  * fc_eh_host_reset() - The reset function will reset the ports on the host.
2014  * @sc_cmd:     scsi command
2015  */
2016 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2017 {
2018         struct Scsi_Host *shost = sc_cmd->device->host;
2019         struct fc_lport *lp = shost_priv(shost);
2020         unsigned long wait_tmo;
2021
2022         FC_SCSI_DBG(lp, "Resetting host\n");
2023
2024         lp->tt.lport_reset(lp);
2025         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2026         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
2027                 msleep(1000);
2028
2029         if (fc_fcp_lport_queue_ready(lp)) {
2030                 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2031                              "on port (%6x)\n", fc_host_port_id(lp->host));
2032                 return SUCCESS;
2033         } else {
2034                 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2035                              "port (%6x) is not ready.\n",
2036                              fc_host_port_id(lp->host));
2037                 return FAILED;
2038         }
2039 }
2040 EXPORT_SYMBOL(fc_eh_host_reset);
2041
2042 /**
2043  * fc_slave_alloc() - configure queue depth
2044  * @sdev:       scsi device
2045  *
2046  * Configures queue depth based on host's cmd_per_len. If not set
2047  * then we use the libfc default.
2048  */
2049 int fc_slave_alloc(struct scsi_device *sdev)
2050 {
2051         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2052
2053         if (!rport || fc_remote_port_chkready(rport))
2054                 return -ENXIO;
2055
2056         if (sdev->tagged_supported)
2057                 scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2058         else
2059                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
2060                                         FC_FCP_DFLT_QUEUE_DEPTH);
2061
2062         return 0;
2063 }
2064 EXPORT_SYMBOL(fc_slave_alloc);
2065
2066 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
2067 {
2068         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2069         return sdev->queue_depth;
2070 }
2071 EXPORT_SYMBOL(fc_change_queue_depth);
2072
2073 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2074 {
2075         if (sdev->tagged_supported) {
2076                 scsi_set_tag_type(sdev, tag_type);
2077                 if (tag_type)
2078                         scsi_activate_tcq(sdev, sdev->queue_depth);
2079                 else
2080                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2081         } else
2082                 tag_type = 0;
2083
2084         return tag_type;
2085 }
2086 EXPORT_SYMBOL(fc_change_queue_type);
2087
2088 void fc_fcp_destroy(struct fc_lport *lp)
2089 {
2090         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2091
2092         if (!list_empty(&si->scsi_pkt_queue))
2093                 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2094                        "port (%6x)\n", fc_host_port_id(lp->host));
2095
2096         mempool_destroy(si->scsi_pkt_pool);
2097         kfree(si);
2098         lp->scsi_priv = NULL;
2099 }
2100 EXPORT_SYMBOL(fc_fcp_destroy);
2101
2102 int fc_fcp_init(struct fc_lport *lp)
2103 {
2104         int rc;
2105         struct fc_fcp_internal *si;
2106
2107         if (!lp->tt.fcp_cmd_send)
2108                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2109
2110         if (!lp->tt.fcp_cleanup)
2111                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2112
2113         if (!lp->tt.fcp_abort_io)
2114                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2115
2116         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2117         if (!si)
2118                 return -ENOMEM;
2119         lp->scsi_priv = si;
2120         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2121
2122         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2123         if (!si->scsi_pkt_pool) {
2124                 rc = -ENOMEM;
2125                 goto free_internal;
2126         }
2127         return 0;
2128
2129 free_internal:
2130         kfree(si);
2131         return rc;
2132 }
2133 EXPORT_SYMBOL(fc_fcp_init);
2134
2135 static int __init libfc_init(void)
2136 {
2137         int rc;
2138
2139         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2140                                             sizeof(struct fc_fcp_pkt),
2141                                             0, SLAB_HWCACHE_ALIGN, NULL);
2142         if (scsi_pkt_cachep == NULL) {
2143                 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2144                        "module load failed!");
2145                 return -ENOMEM;
2146         }
2147
2148         rc = fc_setup_exch_mgr();
2149         if (rc)
2150                 goto destroy_pkt_cache;
2151
2152         rc = fc_setup_rport();
2153         if (rc)
2154                 goto destroy_em;
2155
2156         return rc;
2157 destroy_em:
2158         fc_destroy_exch_mgr();
2159 destroy_pkt_cache:
2160         kmem_cache_destroy(scsi_pkt_cachep);
2161         return rc;
2162 }
2163
2164 static void __exit libfc_exit(void)
2165 {
2166         kmem_cache_destroy(scsi_pkt_cachep);
2167         fc_destroy_exch_mgr();
2168         fc_destroy_rport();
2169 }
2170
2171 module_init(libfc_init);
2172 module_exit(libfc_exit);