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 #include "fc_libfc.h"
  43
  44 static struct kmem_cache *scsi_pkt_cachep;
  45
  46 /* SRB state definitions */
  47 #define FC_SRB_FREE             0               /* cmd is free */
  48 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
  49 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
  50 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
  51 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
  52 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
  53 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
  54 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
  55 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
  56
  57 #define FC_SRB_READ             (1 << 1)
  58 #define FC_SRB_WRITE            (1 << 0)
  59
  60 /*
  61  * The SCp.ptr should be tested and set under the host lock. NULL indicates
  62  * that the command has been retruned to the scsi layer.
  63  */
  64 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
  65 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
  66 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
  67 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
  68 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
  69
  70 struct fc_fcp_internal {
  71         mempool_t       *scsi_pkt_pool;
  72         struct list_head scsi_pkt_queue;
  73         u8              throttled;
  74 };
  75
  76 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
  77
  78 /*
  79  * function prototypes
  80  * FC scsi I/O related functions
  81  */
  82 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
  83 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
  84 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
  85 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
  86 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
  87 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
  88 static void fc_timeout_error(struct fc_fcp_pkt *);
  89 static void fc_fcp_timeout(unsigned long data);
  90 static void fc_fcp_rec(struct fc_fcp_pkt *);
  91 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
  92 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
  93 static void fc_io_compl(struct fc_fcp_pkt *);
  94
  95 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
  96 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
  97 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
  98
  99 /*
 100  * command status codes
 101  */
 102 #define FC_COMPLETE             0
 103 #define FC_CMD_ABORTED          1
 104 #define FC_CMD_RESET            2
 105 #define FC_CMD_PLOGO            3
 106 #define FC_SNS_RCV              4
 107 #define FC_TRANS_ERR            5
 108 #define FC_DATA_OVRRUN          6
 109 #define FC_DATA_UNDRUN          7
 110 #define FC_ERROR                8
 111 #define FC_HRD_ERROR            9
 112 #define FC_CMD_TIME_OUT         10
 113
 114 /*
 115  * Error recovery timeout values.
 116  */
 117 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 118 #define FC_SCSI_TM_TOV          (10 * HZ)
 119 #define FC_SCSI_REC_TOV         (2 * HZ)
 120 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 121
 122 #define FC_MAX_ERROR_CNT        5
 123 #define FC_MAX_RECOV_RETRY      3
 124
 125 #define FC_FCP_DFLT_QUEUE_DEPTH 32
 126
 127 /**
 128  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 129  * @lp:         fc lport struct
 130  * @gfp:        gfp flags for allocation
 131  *
 132  * This is used by upper layer scsi driver.
 133  * Return Value : scsi_pkt structure or null on allocation failure.
 134  * Context      : call from process context. no locking required.
 135  */
 136 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
 137 {
 138         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 139         struct fc_fcp_pkt *fsp;
 140
 141         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
 142         if (fsp) {
 143                 memset(fsp, 0, sizeof(*fsp));
 144                 fsp->lp = lp;
 145                 atomic_set(&fsp->ref_cnt, 1);
 146                 init_timer(&fsp->timer);
 147                 INIT_LIST_HEAD(&fsp->list);
 148                 spin_lock_init(&fsp->scsi_pkt_lock);
 149         }
 150         return fsp;
 151 }
 152
 153 /**
 154  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
 155  * @fsp:        fcp packet struct
 156  *
 157  * This is used by upper layer scsi driver.
 158  * Context      : call from process  and interrupt context.
 159  *                no locking required
 160  */
 161 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
 162 {
 163         if (atomic_dec_and_test(&fsp->ref_cnt)) {
 164                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
 165
 166                 mempool_free(fsp, si->scsi_pkt_pool);
 167         }
 168 }
 169
 170 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
 171 {
 172         atomic_inc(&fsp->ref_cnt);
 173 }
 174
 175 /**
 176  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
 177  * @seq:                exchange sequence
 178  * @fsp:        fcp packet struct
 179  *
 180  * Release hold on scsi_pkt packet set to keep scsi_pkt
 181  * till EM layer exch resource is not freed.
 182  * Context      : called from from EM layer.
 183  *                no locking required
 184  */
 185 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
 186 {
 187         fc_fcp_pkt_release(fsp);
 188 }
 189
 190 /**
 191  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
 192  * @fsp:        fcp packet
 193  *
 194  * We should only return error if we return a command to scsi-ml before
 195  * getting a response. This can happen in cases where we send a abort, but
 196  * do not wait for the response and the abort and command can be passing
 197  * each other on the wire/network-layer.
 198  *
 199  * Note: this function locks the packet and gets a reference to allow
 200  * callers to call the completion function while the lock is held and
 201  * not have to worry about the packets refcount.
 202  *
 203  * TODO: Maybe we should just have callers grab/release the lock and
 204  * have a function that they call to verify the fsp and grab a ref if
 205  * needed.
 206  */
 207 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
 208 {
 209         spin_lock_bh(&fsp->scsi_pkt_lock);
 210         if (fsp->state & FC_SRB_COMPL) {
 211                 spin_unlock_bh(&fsp->scsi_pkt_lock);
 212                 return -EPERM;
 213         }
 214
 215         fc_fcp_pkt_hold(fsp);
 216         return 0;
 217 }
 218
 219 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
 220 {
 221         spin_unlock_bh(&fsp->scsi_pkt_lock);
 222         fc_fcp_pkt_release(fsp);
 223 }
 224
 225 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
 226 {
 227         if (!(fsp->state & FC_SRB_COMPL))
 228                 mod_timer(&fsp->timer, jiffies + delay);
 229 }
 230
 231 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 232 {
 233         if (!fsp->seq_ptr)
 234                 return -EINVAL;
 235
 236         fsp->state |= FC_SRB_ABORT_PENDING;
 237         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 238 }
 239
 240 /*
 241  * Retry command.
 242  * An abort isn't needed.
 243  */
 244 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
 245 {
 246         if (fsp->seq_ptr) {
 247                 fsp->lp->tt.exch_done(fsp->seq_ptr);
 248                 fsp->seq_ptr = NULL;
 249         }
 250
 251         fsp->state &= ~FC_SRB_ABORT_PENDING;
 252         fsp->io_status = 0;
 253         fsp->status_code = FC_ERROR;
 254         fc_fcp_complete_locked(fsp);
 255 }
 256
 257 /*
 258  * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
 259  * transfer for a read I/O indicated by the fc_fcp_pkt.
 260  * @fsp: ptr to the fc_fcp_pkt
 261  *
 262  * This is called in exch_seq_send() when we have a newly allocated
 263  * exchange with a valid exchange id to setup ddp.
 264  *
 265  * returns: none
 266  */
 267 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
 268 {
 269         struct fc_lport *lp;
 270
 271         if (!fsp)
 272                 return;
 273
 274         lp = fsp->lp;
 275         if ((fsp->req_flags & FC_SRB_READ) &&
 276             (lp->lro_enabled) && (lp->tt.ddp_setup)) {
 277                 if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
 278                                      scsi_sg_count(fsp->cmd)))
 279                         fsp->xfer_ddp = xid;
 280         }
 281 }
 282
 283 /*
 284  * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
 285  * DDP related resources for this I/O if it is initialized
 286  * as a ddp transfer
 287  * @fsp: ptr to the fc_fcp_pkt
 288  *
 289  * returns: none
 290  */
 291 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
 292 {
 293         struct fc_lport *lp;
 294
 295         if (!fsp)
 296                 return;
 297
 298         if (fsp->xfer_ddp == FC_XID_UNKNOWN)
 299                 return;
 300
 301         lp = fsp->lp;
 302         if (lp->tt.ddp_done) {
 303                 fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
 304                 fsp->xfer_ddp = FC_XID_UNKNOWN;
 305         }
 306 }
 307
 308
 309 /*
 310  * Receive SCSI data from target.
 311  * Called after receiving solicited data.
 312  */
 313 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 314 {
 315         struct scsi_cmnd *sc = fsp->cmd;
 316         struct fc_lport *lp = fsp->lp;
 317         struct fcoe_dev_stats *stats;
 318         struct fc_frame_header *fh;
 319         size_t start_offset;
 320         size_t offset;
 321         u32 crc;
 322         u32 copy_len = 0;
 323         size_t len;
 324         void *buf;
 325         struct scatterlist *sg;
 326         size_t remaining;
 327
 328         fh = fc_frame_header_get(fp);
 329         offset = ntohl(fh->fh_parm_offset);
 330         start_offset = offset;
 331         len = fr_len(fp) - sizeof(*fh);
 332         buf = fc_frame_payload_get(fp, 0);
 333
 334         /* if this I/O is ddped, update xfer len */
 335         fc_fcp_ddp_done(fsp);
 336
 337         if (offset + len > fsp->data_len) {
 338                 /* this should never happen */
 339                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
 340                     fc_frame_crc_check(fp))
 341                         goto crc_err;
 342                 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
 343                            "data_len %x\n", len, offset, fsp->data_len);
 344                 fc_fcp_retry_cmd(fsp);
 345                 return;
 346         }
 347         if (offset != fsp->xfer_len)
 348                 fsp->state |= FC_SRB_DISCONTIG;
 349
 350         crc = 0;
 351         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 352                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
 353
 354         sg = scsi_sglist(sc);
 355         remaining = len;
 356
 357         while (remaining > 0 && sg) {
 358                 size_t off;
 359                 void *page_addr;
 360                 size_t sg_bytes;
 361
 362                 if (offset >= sg->length) {
 363                         offset -= sg->length;
 364                         sg = sg_next(sg);
 365                         continue;
 366                 }
 367                 sg_bytes = min(remaining, sg->length - offset);
 368
 369                 /*
 370                  * The scatterlist item may be bigger than PAGE_SIZE,
 371                  * but we are limited to mapping PAGE_SIZE at a time.
 372                  */
 373                 off = offset + sg->offset;
 374                 sg_bytes = min(sg_bytes, (size_t)
 375                                (PAGE_SIZE - (off & ~PAGE_MASK)));
 376                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
 377                                         KM_SOFTIRQ0);
 378                 if (!page_addr)
 379                         break;          /* XXX panic? */
 380
 381                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 382                         crc = crc32(crc, buf, sg_bytes);
 383                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
 384                        sg_bytes);
 385
 386                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
 387                 buf += sg_bytes;
 388                 offset += sg_bytes;
 389                 remaining -= sg_bytes;
 390                 copy_len += sg_bytes;
 391         }
 392
 393         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
 394                 buf = fc_frame_payload_get(fp, 0);
 395                 if (len % 4) {
 396                         crc = crc32(crc, buf + len, 4 - (len % 4));
 397                         len += 4 - (len % 4);
 398                 }
 399
 400                 if (~crc != le32_to_cpu(fr_crc(fp))) {
 401 crc_err:
 402                         stats = fc_lport_get_stats(lp);
 403                         stats->ErrorFrames++;
 404                         /* FIXME - per cpu count, not total count! */
 405                         if (stats->InvalidCRCCount++ < 5)
 406                                 printk(KERN_WARNING "libfc: CRC error on data "
 407                                        "frame for port (%6x)\n",
 408                                        fc_host_port_id(lp->host));
 409                         /*
 410                          * Assume the frame is total garbage.
 411                          * We may have copied it over the good part
 412                          * of the buffer.
 413                          * If so, we need to retry the entire operation.
 414                          * Otherwise, ignore it.
 415                          */
 416                         if (fsp->state & FC_SRB_DISCONTIG)
 417                                 fc_fcp_retry_cmd(fsp);
 418                         return;
 419                 }
 420         }
 421
 422         if (fsp->xfer_contig_end == start_offset)
 423                 fsp->xfer_contig_end += copy_len;
 424         fsp->xfer_len += copy_len;
 425
 426         /*
 427          * In the very rare event that this data arrived after the response
 428          * and completes the transfer, call the completion handler.
 429          */
 430         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
 431             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
 432                 fc_fcp_complete_locked(fsp);
 433 }
 434
 435 /**
 436  * fc_fcp_send_data() -  Send SCSI data to target.
 437  * @fsp: ptr to fc_fcp_pkt
 438  * @sp: ptr to this sequence
 439  * @offset: starting offset for this data request
 440  * @seq_blen: the burst length for this data request
 441  *
 442  * Called after receiving a Transfer Ready data descriptor.
 443  * if LLD is capable of seq offload then send down seq_blen
 444  * size of data in single frame, otherwise send multiple FC
 445  * frames of max FC frame payload supported by target port.
 446  *
 447  * Returns : 0 for success.
 448  */
 449 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
 450                             size_t offset, size_t seq_blen)
 451 {
 452         struct fc_exch *ep;
 453         struct scsi_cmnd *sc;
 454         struct scatterlist *sg;
 455         struct fc_frame *fp = NULL;
 456         struct fc_lport *lp = fsp->lp;
 457         size_t remaining;
 458         size_t t_blen;
 459         size_t tlen;
 460         size_t sg_bytes;
 461         size_t frame_offset, fh_parm_offset;
 462         int error;
 463         void *data = NULL;
 464         void *page_addr;
 465         int using_sg = lp->sg_supp;
 466         u32 f_ctl;
 467
 468         WARN_ON(seq_blen <= 0);
 469         if (unlikely(offset + seq_blen > fsp->data_len)) {
 470                 /* this should never happen */
 471                 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
 472                            "offset %zx\n", seq_blen, offset);
 473                 fc_fcp_send_abort(fsp);
 474                 return 0;
 475         } else if (offset != fsp->xfer_len) {
 476                 /* Out of Order Data Request - no problem, but unexpected. */
 477                 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
 478                            "seq_blen %zx offset %zx\n", seq_blen, offset);
 479         }
 480
 481         /*
 482          * if LLD is capable of seq_offload then set transport
 483          * burst length (t_blen) to seq_blen, otherwise set t_blen
 484          * to max FC frame payload previously set in fsp->max_payload.
 485          */
 486         t_blen = fsp->max_payload;
 487         if (lp->seq_offload) {
 488                 t_blen = min(seq_blen, (size_t)lp->lso_max);
 489                 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
 490                            fsp, seq_blen, lp->lso_max, t_blen);
 491         }
 492
 493         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
 494         if (t_blen > 512)
 495                 t_blen &= ~(512 - 1);   /* round down to block size */
 496         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
 497         sc = fsp->cmd;
 498
 499         remaining = seq_blen;
 500         fh_parm_offset = frame_offset = offset;
 501         tlen = 0;
 502         seq = lp->tt.seq_start_next(seq);
 503         f_ctl = FC_FC_REL_OFF;
 504         WARN_ON(!seq);
 505
 506         sg = scsi_sglist(sc);
 507
 508         while (remaining > 0 && sg) {
 509                 if (offset >= sg->length) {
 510                         offset -= sg->length;
 511                         sg = sg_next(sg);
 512                         continue;
 513                 }
 514                 if (!fp) {
 515                         tlen = min(t_blen, remaining);
 516
 517                         /*
 518                          * TODO.  Temporary workaround.  fc_seq_send() can't
 519                          * handle odd lengths in non-linear skbs.
 520                          * This will be the final fragment only.
 521                          */
 522                         if (tlen % 4)
 523                                 using_sg = 0;
 524                         if (using_sg) {
 525                                 fp = _fc_frame_alloc(lp, 0);
 526                                 if (!fp)
 527                                         return -ENOMEM;
 528                         } else {
 529                                 fp = fc_frame_alloc(lp, tlen);
 530                                 if (!fp)
 531                                         return -ENOMEM;
 532
 533                                 data = (void *)(fr_hdr(fp)) +
 534                                         sizeof(struct fc_frame_header);
 535                         }
 536                         fh_parm_offset = frame_offset;
 537                         fr_max_payload(fp) = fsp->max_payload;
 538                 }
 539                 sg_bytes = min(tlen, sg->length - offset);
 540                 if (using_sg) {
 541                         get_page(sg_page(sg));
 542                         skb_fill_page_desc(fp_skb(fp),
 543                                            skb_shinfo(fp_skb(fp))->nr_frags,
 544                                            sg_page(sg), sg->offset + offset,
 545                                            sg_bytes);
 546                         fp_skb(fp)->data_len += sg_bytes;
 547                         fr_len(fp) += sg_bytes;
 548                         fp_skb(fp)->truesize += PAGE_SIZE;
 549                 } else {
 550                         size_t off = offset + sg->offset;
 551
 552                         /*
 553                          * The scatterlist item may be bigger than PAGE_SIZE,
 554                          * but we must not cross pages inside the kmap.
 555                          */
 556                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
 557                                                            (off & ~PAGE_MASK)));
 558                         page_addr = kmap_atomic(sg_page(sg) +
 559                                                 (off >> PAGE_SHIFT),
 560                                                 KM_SOFTIRQ0);
 561                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
 562                                sg_bytes);
 563                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
 564                         data += sg_bytes;
 565                 }
 566                 offset += sg_bytes;
 567                 frame_offset += sg_bytes;
 568                 tlen -= sg_bytes;
 569                 remaining -= sg_bytes;
 570
 571                 if ((skb_shinfo(fp_skb(fp))->nr_frags < FC_FRAME_SG_LEN) &&
 572                     (tlen))
 573                         continue;
 574
 575                 /*
 576                  * Send sequence with transfer sequence initiative in case
 577                  * this is last FCP frame of the sequence.
 578                  */
 579                 if (remaining == 0)
 580                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
 581
 582                 ep = fc_seq_exch(seq);
 583                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
 584                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
 585
 586                 /*
 587                  * send fragment using for a sequence.
 588                  */
 589                 error = lp->tt.seq_send(lp, seq, fp);
 590                 if (error) {
 591                         WARN_ON(1);             /* send error should be rare */
 592                         fc_fcp_retry_cmd(fsp);
 593                         return 0;
 594                 }
 595                 fp = NULL;
 596         }
 597         fsp->xfer_len += seq_blen;      /* premature count? */
 598         return 0;
 599 }
 600
 601 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 602 {
 603         int ba_done = 1;
 604         struct fc_ba_rjt *brp;
 605         struct fc_frame_header *fh;
 606
 607         fh = fc_frame_header_get(fp);
 608         switch (fh->fh_r_ctl) {
 609         case FC_RCTL_BA_ACC:
 610                 break;
 611         case FC_RCTL_BA_RJT:
 612                 brp = fc_frame_payload_get(fp, sizeof(*brp));
 613                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
 614                         break;
 615                 /* fall thru */
 616         default:
 617                 /*
 618                  * we will let the command timeout
 619                  * and scsi-ml recover in this case,
 620                  * therefore cleared the ba_done flag.
 621                  */
 622                 ba_done = 0;
 623         }
 624
 625         if (ba_done) {
 626                 fsp->state |= FC_SRB_ABORTED;
 627                 fsp->state &= ~FC_SRB_ABORT_PENDING;
 628
 629                 if (fsp->wait_for_comp)
 630                         complete(&fsp->tm_done);
 631                 else
 632                         fc_fcp_complete_locked(fsp);
 633         }
 634 }
 635
 636 /**
 637  * fc_fcp_reduce_can_queue() - drop can_queue
 638  * @lp: lport to drop queueing for
 639  *
 640  * If we are getting memory allocation failures, then we may
 641  * be trying to execute too many commands. We let the running
 642  * commands complete or timeout, then try again with a reduced
 643  * can_queue. Eventually we will hit the point where we run
 644  * on all reserved structs.
 645  */
 646 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
 647 {
 648         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 649         unsigned long flags;
 650         int can_queue;
 651
 652         spin_lock_irqsave(lp->host->host_lock, flags);
 653         if (si->throttled)
 654                 goto done;
 655         si->throttled = 1;
 656
 657         can_queue = lp->host->can_queue;
 658         can_queue >>= 1;
 659         if (!can_queue)
 660                 can_queue = 1;
 661         lp->host->can_queue = can_queue;
 662         shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n"
 663                      "Reducing can_queue to %d.\n", can_queue);
 664 done:
 665         spin_unlock_irqrestore(lp->host->host_lock, flags);
 666 }
 667
 668 /**
 669  * fc_fcp_recv() - Reveive FCP frames
 670  * @seq: The sequence the frame is on
 671  * @fp: The FC frame
 672  * @arg: The related FCP packet
 673  *
 674  * Return   : None
 675  * Context  : called from Soft IRQ context
 676  *            can not called holding list lock
 677  */
 678 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 679 {
 680         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
 681         struct fc_lport *lport = fsp->lp;
 682         struct fc_frame_header *fh;
 683         struct fcp_txrdy *dd;
 684         u8 r_ctl;
 685         int rc = 0;
 686
 687         if (IS_ERR(fp))
 688                 goto errout;
 689
 690         fh = fc_frame_header_get(fp);
 691         r_ctl = fh->fh_r_ctl;
 692
 693         if (!(lport->state & LPORT_ST_READY))
 694                 goto out;
 695         if (fc_fcp_lock_pkt(fsp))
 696                 goto out;
 697         fsp->last_pkt_time = jiffies;
 698
 699         if (fh->fh_type == FC_TYPE_BLS) {
 700                 fc_fcp_abts_resp(fsp, fp);
 701                 goto unlock;
 702         }
 703
 704         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
 705                 goto unlock;
 706
 707         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
 708                 /*
 709                  * received XFER RDY from the target
 710                  * need to send data to the target
 711                  */
 712                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 713                 dd = fc_frame_payload_get(fp, sizeof(*dd));
 714                 WARN_ON(!dd);
 715
 716                 rc = fc_fcp_send_data(fsp, seq,
 717                                       (size_t) ntohl(dd->ft_data_ro),
 718                                       (size_t) ntohl(dd->ft_burst_len));
 719                 if (!rc)
 720                         seq->rec_data = fsp->xfer_len;
 721                 else if (rc == -ENOMEM)
 722                         fsp->state |= FC_SRB_NOMEM;
 723         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
 724                 /*
 725                  * received a DATA frame
 726                  * next we will copy the data to the system buffer
 727                  */
 728                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
 729                 fc_fcp_recv_data(fsp, fp);
 730                 seq->rec_data = fsp->xfer_contig_end;
 731         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
 732                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 733
 734                 fc_fcp_resp(fsp, fp);
 735         } else {
 736                 FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
 737         }
 738 unlock:
 739         fc_fcp_unlock_pkt(fsp);
 740 out:
 741         fc_frame_free(fp);
 742 errout:
 743         if (IS_ERR(fp))
 744                 fc_fcp_error(fsp, fp);
 745         else if (rc == -ENOMEM)
 746                 fc_fcp_reduce_can_queue(lport);
 747 }
 748
 749 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 750 {
 751         struct fc_frame_header *fh;
 752         struct fcp_resp *fc_rp;
 753         struct fcp_resp_ext *rp_ex;
 754         struct fcp_resp_rsp_info *fc_rp_info;
 755         u32 plen;
 756         u32 expected_len;
 757         u32 respl = 0;
 758         u32 snsl = 0;
 759         u8 flags = 0;
 760
 761         plen = fr_len(fp);
 762         fh = (struct fc_frame_header *)fr_hdr(fp);
 763         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
 764                 goto len_err;
 765         plen -= sizeof(*fh);
 766         fc_rp = (struct fcp_resp *)(fh + 1);
 767         fsp->cdb_status = fc_rp->fr_status;
 768         flags = fc_rp->fr_flags;
 769         fsp->scsi_comp_flags = flags;
 770         expected_len = fsp->data_len;
 771
 772         /* if ddp, update xfer len */
 773         fc_fcp_ddp_done(fsp);
 774
 775         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
 776                 rp_ex = (void *)(fc_rp + 1);
 777                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
 778                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
 779                                 goto len_err;
 780                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
 781                         if (flags & FCP_RSP_LEN_VAL) {
 782                                 respl = ntohl(rp_ex->fr_rsp_len);
 783                                 if (respl != sizeof(*fc_rp_info))
 784                                         goto len_err;
 785                                 if (fsp->wait_for_comp) {
 786                                         /* Abuse cdb_status for rsp code */
 787                                         fsp->cdb_status = fc_rp_info->rsp_code;
 788                                         complete(&fsp->tm_done);
 789                                         /*
 790                                          * tmfs will not have any scsi cmd so
 791                                          * exit here
 792                                          */
 793                                         return;
 794                                 } else
 795                                         goto err;
 796                         }
 797                         if (flags & FCP_SNS_LEN_VAL) {
 798                                 snsl = ntohl(rp_ex->fr_sns_len);
 799                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
 800                                         snsl = SCSI_SENSE_BUFFERSIZE;
 801                                 memcpy(fsp->cmd->sense_buffer,
 802                                        (char *)fc_rp_info + respl, snsl);
 803                         }
 804                 }
 805                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
 806                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
 807                                 goto len_err;
 808                         if (flags & FCP_RESID_UNDER) {
 809                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
 810                                 /*
 811                                  * The cmnd->underflow is the minimum number of
 812                                  * bytes that must be transfered for this
 813                                  * command.  Provided a sense condition is not
 814                                  * present, make sure the actual amount
 815                                  * transferred is at least the underflow value
 816                                  * or fail.
 817                                  */
 818                                 if (!(flags & FCP_SNS_LEN_VAL) &&
 819                                     (fc_rp->fr_status == 0) &&
 820                                     (scsi_bufflen(fsp->cmd) -
 821                                      fsp->scsi_resid) < fsp->cmd->underflow)
 822                                         goto err;
 823                                 expected_len -= fsp->scsi_resid;
 824                         } else {
 825                                 fsp->status_code = FC_ERROR;
 826                         }
 827                 }
 828         }
 829         fsp->state |= FC_SRB_RCV_STATUS;
 830
 831         /*
 832          * Check for missing or extra data frames.
 833          */
 834         if (unlikely(fsp->xfer_len != expected_len)) {
 835                 if (fsp->xfer_len < expected_len) {
 836                         /*
 837                          * Some data may be queued locally,
 838                          * Wait a at least one jiffy to see if it is delivered.
 839                          * If this expires without data, we may do SRR.
 840                          */
 841                         fc_fcp_timer_set(fsp, 2);
 842                         return;
 843                 }
 844                 fsp->status_code = FC_DATA_OVRRUN;
 845                 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
 846                            "len %x, data len %x\n",
 847                            fsp->rport->port_id,
 848                            fsp->xfer_len, expected_len, fsp->data_len);
 849         }
 850         fc_fcp_complete_locked(fsp);
 851         return;
 852
 853 len_err:
 854         FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
 855                    "snsl %u\n", flags, fr_len(fp), respl, snsl);
 856 err:
 857         fsp->status_code = FC_ERROR;
 858         fc_fcp_complete_locked(fsp);
 859 }
 860
 861 /**
 862  * fc_fcp_complete_locked() - complete processing of a fcp packet
 863  * @fsp:        fcp packet
 864  *
 865  * This function may sleep if a timer is pending. The packet lock must be
 866  * held, and the host lock must not be held.
 867  */
 868 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
 869 {
 870         struct fc_lport *lp = fsp->lp;
 871         struct fc_seq *seq;
 872         struct fc_exch *ep;
 873         u32 f_ctl;
 874
 875         if (fsp->state & FC_SRB_ABORT_PENDING)
 876                 return;
 877
 878         if (fsp->state & FC_SRB_ABORTED) {
 879                 if (!fsp->status_code)
 880                         fsp->status_code = FC_CMD_ABORTED;
 881         } else {
 882                 /*
 883                  * Test for transport underrun, independent of response
 884                  * underrun status.
 885                  */
 886                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
 887                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
 888                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
 889                         fsp->status_code = FC_DATA_UNDRUN;
 890                         fsp->io_status = 0;
 891                 }
 892         }
 893
 894         seq = fsp->seq_ptr;
 895         if (seq) {
 896                 fsp->seq_ptr = NULL;
 897                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
 898                         struct fc_frame *conf_frame;
 899                         struct fc_seq *csp;
 900
 901                         csp = lp->tt.seq_start_next(seq);
 902                         conf_frame = fc_frame_alloc(fsp->lp, 0);
 903                         if (conf_frame) {
 904                                 f_ctl = FC_FC_SEQ_INIT;
 905                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
 906                                 ep = fc_seq_exch(seq);
 907                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
 908                                                ep->did, ep->sid,
 909                                                FC_TYPE_FCP, f_ctl, 0);
 910                                 lp->tt.seq_send(lp, csp, conf_frame);
 911                         }
 912                 }
 913                 lp->tt.exch_done(seq);
 914         }
 915         fc_io_compl(fsp);
 916 }
 917
 918 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
 919 {
 920         struct fc_lport *lp = fsp->lp;
 921
 922         if (fsp->seq_ptr) {
 923                 lp->tt.exch_done(fsp->seq_ptr);
 924                 fsp->seq_ptr = NULL;
 925         }
 926         fsp->status_code = error;
 927 }
 928
 929 /**
 930  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
 931  * @lp:         logical port
 932  * @id:         target id
 933  * @lun:        lun
 934  * @error:      fsp status code
 935  *
 936  * If lun or id is -1, they are ignored.
 937  */
 938 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
 939                                     unsigned int lun, int error)
 940 {
 941         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 942         struct fc_fcp_pkt *fsp;
 943         struct scsi_cmnd *sc_cmd;
 944         unsigned long flags;
 945
 946         spin_lock_irqsave(lp->host->host_lock, flags);
 947 restart:
 948         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
 949                 sc_cmd = fsp->cmd;
 950                 if (id != -1 && scmd_id(sc_cmd) != id)
 951                         continue;
 952
 953                 if (lun != -1 && sc_cmd->device->lun != lun)
 954                         continue;
 955
 956                 fc_fcp_pkt_hold(fsp);
 957                 spin_unlock_irqrestore(lp->host->host_lock, flags);
 958
 959                 if (!fc_fcp_lock_pkt(fsp)) {
 960                         fc_fcp_cleanup_cmd(fsp, error);
 961                         fc_io_compl(fsp);
 962                         fc_fcp_unlock_pkt(fsp);
 963                 }
 964
 965                 fc_fcp_pkt_release(fsp);
 966                 spin_lock_irqsave(lp->host->host_lock, flags);
 967                 /*
 968                  * while we dropped the lock multiple pkts could
 969                  * have been released, so we have to start over.
 970                  */
 971                 goto restart;
 972         }
 973         spin_unlock_irqrestore(lp->host->host_lock, flags);
 974 }
 975
 976 static void fc_fcp_abort_io(struct fc_lport *lp)
 977 {
 978         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
 979 }
 980
 981 /**
 982  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
 983  * @lp:         fc lport
 984  * @fsp:        fc packet.
 985  *
 986  * This is called by upper layer protocol.
 987  * Return   : zero for success and -1 for failure
 988  * Context  : called from queuecommand which can be called from process
 989  *            or scsi soft irq.
 990  * Locks    : called with the host lock and irqs disabled.
 991  */
 992 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
 993 {
 994         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 995         int rc;
 996
 997         fsp->cmd->SCp.ptr = (char *)fsp;
 998         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
 999         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1000
1001         int_to_scsilun(fsp->cmd->device->lun,
1002                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1003         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1004         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1005
1006         spin_unlock_irq(lp->host->host_lock);
1007         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
1008         spin_lock_irq(lp->host->host_lock);
1009         if (rc)
1010                 list_del(&fsp->list);
1011
1012         return rc;
1013 }
1014
1015 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1016                            void (*resp)(struct fc_seq *,
1017                                         struct fc_frame *fp,
1018                                         void *arg))
1019 {
1020         struct fc_frame *fp;
1021         struct fc_seq *seq;
1022         struct fc_rport *rport;
1023         struct fc_rport_libfc_priv *rp;
1024         const size_t len = sizeof(fsp->cdb_cmd);
1025         int rc = 0;
1026
1027         if (fc_fcp_lock_pkt(fsp))
1028                 return 0;
1029
1030         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1031         if (!fp) {
1032                 rc = -1;
1033                 goto unlock;
1034         }
1035
1036         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1037         fr_fsp(fp) = fsp;
1038         rport = fsp->rport;
1039         fsp->max_payload = rport->maxframe_size;
1040         rp = rport->dd_data;
1041
1042         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1043                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1044                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1045
1046         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1047         if (!seq) {
1048                 rc = -1;
1049                 goto unlock;
1050         }
1051         fsp->last_pkt_time = jiffies;
1052         fsp->seq_ptr = seq;
1053         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1054
1055         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1056         fc_fcp_timer_set(fsp,
1057                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1058                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1059 unlock:
1060         fc_fcp_unlock_pkt(fsp);
1061         return rc;
1062 }
1063
1064 /*
1065  * transport error handler
1066  */
1067 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1068 {
1069         int error = PTR_ERR(fp);
1070
1071         if (fc_fcp_lock_pkt(fsp))
1072                 return;
1073
1074         if (error == -FC_EX_CLOSED) {
1075                 fc_fcp_retry_cmd(fsp);
1076                 goto unlock;
1077         }
1078
1079         /*
1080          * clear abort pending, because the lower layer
1081          * decided to force completion.
1082          */
1083         fsp->state &= ~FC_SRB_ABORT_PENDING;
1084         fsp->status_code = FC_CMD_PLOGO;
1085         fc_fcp_complete_locked(fsp);
1086 unlock:
1087         fc_fcp_unlock_pkt(fsp);
1088 }
1089
1090 /*
1091  * Scsi abort handler- calls to send an abort
1092  * and then wait for abort completion
1093  */
1094 static int fc_fcp_pkt_abort(struct fc_fcp_pkt *fsp)
1095 {
1096         int rc = FAILED;
1097
1098         if (fc_fcp_send_abort(fsp))
1099                 return FAILED;
1100
1101         init_completion(&fsp->tm_done);
1102         fsp->wait_for_comp = 1;
1103
1104         spin_unlock_bh(&fsp->scsi_pkt_lock);
1105         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1106         spin_lock_bh(&fsp->scsi_pkt_lock);
1107         fsp->wait_for_comp = 0;
1108
1109         if (!rc) {
1110                 FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1111                 rc = FAILED;
1112         } else if (fsp->state & FC_SRB_ABORTED) {
1113                 FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1114                 rc = SUCCESS;
1115                 fc_fcp_complete_locked(fsp);
1116         }
1117
1118         return rc;
1119 }
1120
1121 /*
1122  * Retry LUN reset after resource allocation failed.
1123  */
1124 static void fc_lun_reset_send(unsigned long data)
1125 {
1126         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1127         struct fc_lport *lp = fsp->lp;
1128         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1129                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1130                         return;
1131                 if (fc_fcp_lock_pkt(fsp))
1132                         return;
1133                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1134                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1135                 fc_fcp_unlock_pkt(fsp);
1136         }
1137 }
1138
1139 /*
1140  * Scsi device reset handler- send a LUN RESET to the device
1141  * and wait for reset reply
1142  */
1143 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1144                         unsigned int id, unsigned int lun)
1145 {
1146         int rc;
1147
1148         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1149         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1150         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1151
1152         fsp->wait_for_comp = 1;
1153         init_completion(&fsp->tm_done);
1154
1155         fc_lun_reset_send((unsigned long)fsp);
1156
1157         /*
1158          * wait for completion of reset
1159          * after that make sure all commands are terminated
1160          */
1161         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1162
1163         spin_lock_bh(&fsp->scsi_pkt_lock);
1164         fsp->state |= FC_SRB_COMPL;
1165         spin_unlock_bh(&fsp->scsi_pkt_lock);
1166
1167         del_timer_sync(&fsp->timer);
1168
1169         spin_lock_bh(&fsp->scsi_pkt_lock);
1170         if (fsp->seq_ptr) {
1171                 lp->tt.exch_done(fsp->seq_ptr);
1172                 fsp->seq_ptr = NULL;
1173         }
1174         fsp->wait_for_comp = 0;
1175         spin_unlock_bh(&fsp->scsi_pkt_lock);
1176
1177         if (!rc) {
1178                 FC_SCSI_DBG(lp, "lun reset failed\n");
1179                 return FAILED;
1180         }
1181
1182         /* cdb_status holds the tmf's rsp code */
1183         if (fsp->cdb_status != FCP_TMF_CMPL)
1184                 return FAILED;
1185
1186         FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun);
1187         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1188         return SUCCESS;
1189 }
1190
1191 /*
1192  * Task Managment response handler
1193  */
1194 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1195 {
1196         struct fc_fcp_pkt *fsp = arg;
1197         struct fc_frame_header *fh;
1198
1199         if (IS_ERR(fp)) {
1200                 /*
1201                  * If there is an error just let it timeout or wait
1202                  * for TMF to be aborted if it timedout.
1203                  *
1204                  * scsi-eh will escalate for when either happens.
1205                  */
1206                 return;
1207         }
1208
1209         if (fc_fcp_lock_pkt(fsp))
1210                 return;
1211
1212         /*
1213          * raced with eh timeout handler.
1214          */
1215         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1216                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1217                 return;
1218         }
1219
1220         fh = fc_frame_header_get(fp);
1221         if (fh->fh_type != FC_TYPE_BLS)
1222                 fc_fcp_resp(fsp, fp);
1223         fsp->seq_ptr = NULL;
1224         fsp->lp->tt.exch_done(seq);
1225         fc_frame_free(fp);
1226         fc_fcp_unlock_pkt(fsp);
1227 }
1228
1229 static void fc_fcp_cleanup(struct fc_lport *lp)
1230 {
1231         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1232 }
1233
1234 /*
1235  * fc_fcp_timeout: called by OS timer function.
1236  *
1237  * The timer has been inactivated and must be reactivated if desired
1238  * using fc_fcp_timer_set().
1239  *
1240  * Algorithm:
1241  *
1242  * If REC is supported, just issue it, and return.  The REC exchange will
1243  * complete or time out, and recovery can continue at that point.
1244  *
1245  * Otherwise, if the response has been received without all the data,
1246  * it has been ER_TIMEOUT since the response was received.
1247  *
1248  * If the response has not been received,
1249  * we see if data was received recently.  If it has been, we continue waiting,
1250  * otherwise, we abort the command.
1251  */
1252 static void fc_fcp_timeout(unsigned long data)
1253 {
1254         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1255         struct fc_rport *rport = fsp->rport;
1256         struct fc_rport_libfc_priv *rp = rport->dd_data;
1257
1258         if (fc_fcp_lock_pkt(fsp))
1259                 return;
1260
1261         if (fsp->cdb_cmd.fc_tm_flags)
1262                 goto unlock;
1263
1264         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1265
1266         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1267                 fc_fcp_rec(fsp);
1268         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1269                                jiffies))
1270                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1271         else if (fsp->state & FC_SRB_RCV_STATUS)
1272                 fc_fcp_complete_locked(fsp);
1273         else
1274                 fc_timeout_error(fsp);
1275         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1276 unlock:
1277         fc_fcp_unlock_pkt(fsp);
1278 }
1279
1280 /*
1281  * Send a REC ELS request
1282  */
1283 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1284 {
1285         struct fc_lport *lp;
1286         struct fc_frame *fp;
1287         struct fc_rport *rport;
1288         struct fc_rport_libfc_priv *rp;
1289
1290         lp = fsp->lp;
1291         rport = fsp->rport;
1292         rp = rport->dd_data;
1293         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1294                 fsp->status_code = FC_HRD_ERROR;
1295                 fsp->io_status = 0;
1296                 fc_fcp_complete_locked(fsp);
1297                 return;
1298         }
1299         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1300         if (!fp)
1301                 goto retry;
1302
1303         fr_seq(fp) = fsp->seq_ptr;
1304         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1305                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1306                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1307         if (lp->tt.elsct_send(lp, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp,
1308                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1309                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1310                 return;
1311         }
1312 retry:
1313         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1314                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1315         else
1316                 fc_timeout_error(fsp);
1317 }
1318
1319 /*
1320  * Receive handler for REC ELS frame
1321  * if it is a reject then let the scsi layer to handle
1322  * the timeout. if it is a LS_ACC then if the io was not completed
1323  * then set the timeout and return otherwise complete the exchange
1324  * and tell the scsi layer to restart the I/O.
1325  */
1326 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1327 {
1328         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1329         struct fc_els_rec_acc *recp;
1330         struct fc_els_ls_rjt *rjt;
1331         u32 e_stat;
1332         u8 opcode;
1333         u32 offset;
1334         enum dma_data_direction data_dir;
1335         enum fc_rctl r_ctl;
1336         struct fc_rport_libfc_priv *rp;
1337
1338         if (IS_ERR(fp)) {
1339                 fc_fcp_rec_error(fsp, fp);
1340                 return;
1341         }
1342
1343         if (fc_fcp_lock_pkt(fsp))
1344                 goto out;
1345
1346         fsp->recov_retry = 0;
1347         opcode = fc_frame_payload_op(fp);
1348         if (opcode == ELS_LS_RJT) {
1349                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1350                 switch (rjt->er_reason) {
1351                 default:
1352                         FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1353                                    "reason %d expl %d\n",
1354                                    fsp->rport->port_id, rjt->er_reason,
1355                                    rjt->er_explan);
1356                         /* fall through */
1357                 case ELS_RJT_UNSUP:
1358                         FC_FCP_DBG(fsp, "device does not support REC\n");
1359                         rp = fsp->rport->dd_data;
1360                         /*
1361                          * if we do not spport RECs or got some bogus
1362                          * reason then resetup timer so we check for
1363                          * making progress.
1364                          */
1365                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1366                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1367                         break;
1368                 case ELS_RJT_LOGIC:
1369                 case ELS_RJT_UNAB:
1370                         /*
1371                          * If no data transfer, the command frame got dropped
1372                          * so we just retry.  If data was transferred, we
1373                          * lost the response but the target has no record,
1374                          * so we abort and retry.
1375                          */
1376                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1377                             fsp->xfer_len == 0) {
1378                                 fc_fcp_retry_cmd(fsp);
1379                                 break;
1380                         }
1381                         fc_timeout_error(fsp);
1382                         break;
1383                 }
1384         } else if (opcode == ELS_LS_ACC) {
1385                 if (fsp->state & FC_SRB_ABORTED)
1386                         goto unlock_out;
1387
1388                 data_dir = fsp->cmd->sc_data_direction;
1389                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1390                 offset = ntohl(recp->reca_fc4value);
1391                 e_stat = ntohl(recp->reca_e_stat);
1392
1393                 if (e_stat & ESB_ST_COMPLETE) {
1394
1395                         /*
1396                          * The exchange is complete.
1397                          *
1398                          * For output, we must've lost the response.
1399                          * For input, all data must've been sent.
1400                          * We lost may have lost the response
1401                          * (and a confirmation was requested) and maybe
1402                          * some data.
1403                          *
1404                          * If all data received, send SRR
1405                          * asking for response.  If partial data received,
1406                          * or gaps, SRR requests data at start of gap.
1407                          * Recovery via SRR relies on in-order-delivery.
1408                          */
1409                         if (data_dir == DMA_TO_DEVICE) {
1410                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1411                         } else if (fsp->xfer_contig_end == offset) {
1412                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1413                         } else {
1414                                 offset = fsp->xfer_contig_end;
1415                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1416                         }
1417                         fc_fcp_srr(fsp, r_ctl, offset);
1418                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1419
1420                         /*
1421                          * The remote port has the initiative, so just
1422                          * keep waiting for it to complete.
1423                          */
1424                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1425                 } else {
1426
1427                         /*
1428                          * The exchange is incomplete, we have seq. initiative.
1429                          * Lost response with requested confirmation,
1430                          * lost confirmation, lost transfer ready or
1431                          * lost write data.
1432                          *
1433                          * For output, if not all data was received, ask
1434                          * for transfer ready to be repeated.
1435                          *
1436                          * If we received or sent all the data, send SRR to
1437                          * request response.
1438                          *
1439                          * If we lost a response, we may have lost some read
1440                          * data as well.
1441                          */
1442                         r_ctl = FC_RCTL_DD_SOL_DATA;
1443                         if (data_dir == DMA_TO_DEVICE) {
1444                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1445                                 if (offset < fsp->data_len)
1446                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1447                         } else if (offset == fsp->xfer_contig_end) {
1448                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1449                         } else if (fsp->xfer_contig_end < offset) {
1450                                 offset = fsp->xfer_contig_end;
1451                         }
1452                         fc_fcp_srr(fsp, r_ctl, offset);
1453                 }
1454         }
1455 unlock_out:
1456         fc_fcp_unlock_pkt(fsp);
1457 out:
1458         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1459         fc_frame_free(fp);
1460 }
1461
1462 /*
1463  * Handle error response or timeout for REC exchange.
1464  */
1465 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1466 {
1467         int error = PTR_ERR(fp);
1468
1469         if (fc_fcp_lock_pkt(fsp))
1470                 goto out;
1471
1472         switch (error) {
1473         case -FC_EX_CLOSED:
1474                 fc_fcp_retry_cmd(fsp);
1475                 break;
1476
1477         default:
1478                 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1479                            fsp, fsp->rport->port_id, error);
1480                 fsp->status_code = FC_CMD_PLOGO;
1481                 /* fall through */
1482
1483         case -FC_EX_TIMEOUT:
1484                 /*
1485                  * Assume REC or LS_ACC was lost.
1486                  * The exchange manager will have aborted REC, so retry.
1487                  */
1488                 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1489                            fsp->rport->port_id, error, fsp->recov_retry,
1490                            FC_MAX_RECOV_RETRY);
1491                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1492                         fc_fcp_rec(fsp);
1493                 else
1494                         fc_timeout_error(fsp);
1495                 break;
1496         }
1497         fc_fcp_unlock_pkt(fsp);
1498 out:
1499         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1500 }
1501
1502 /*
1503  * Time out error routine:
1504  * abort's the I/O close the exchange and
1505  * send completion notification to scsi layer
1506  */
1507 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1508 {
1509         fsp->status_code = FC_CMD_TIME_OUT;
1510         fsp->cdb_status = 0;
1511         fsp->io_status = 0;
1512         /*
1513          * if this fails then we let the scsi command timer fire and
1514          * scsi-ml escalate.
1515          */
1516         fc_fcp_send_abort(fsp);
1517 }
1518
1519 /*
1520  * Sequence retransmission request.
1521  * This is called after receiving status but insufficient data, or
1522  * when expecting status but the request has timed out.
1523  */
1524 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1525 {
1526         struct fc_lport *lp = fsp->lp;
1527         struct fc_rport *rport;
1528         struct fc_rport_libfc_priv *rp;
1529         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1530         struct fc_seq *seq;
1531         struct fcp_srr *srr;
1532         struct fc_frame *fp;
1533         u8 cdb_op;
1534
1535         rport = fsp->rport;
1536         rp = rport->dd_data;
1537         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1538
1539         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1540                 goto retry;                     /* shouldn't happen */
1541         fp = fc_frame_alloc(lp, sizeof(*srr));
1542         if (!fp)
1543                 goto retry;
1544
1545         srr = fc_frame_payload_get(fp, sizeof(*srr));
1546         memset(srr, 0, sizeof(*srr));
1547         srr->srr_op = ELS_SRR;
1548         srr->srr_ox_id = htons(ep->oxid);
1549         srr->srr_rx_id = htons(ep->rxid);
1550         srr->srr_r_ctl = r_ctl;
1551         srr->srr_rel_off = htonl(offset);
1552
1553         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1554                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1555                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1556
1557         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1558                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1559         if (!seq)
1560                 goto retry;
1561
1562         fsp->recov_seq = seq;
1563         fsp->xfer_len = offset;
1564         fsp->xfer_contig_end = offset;
1565         fsp->state &= ~FC_SRB_RCV_STATUS;
1566         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1567         return;
1568 retry:
1569         fc_fcp_retry_cmd(fsp);
1570 }
1571
1572 /*
1573  * Handle response from SRR.
1574  */
1575 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1576 {
1577         struct fc_fcp_pkt *fsp = arg;
1578         struct fc_frame_header *fh;
1579
1580         if (IS_ERR(fp)) {
1581                 fc_fcp_srr_error(fsp, fp);
1582                 return;
1583         }
1584
1585         if (fc_fcp_lock_pkt(fsp))
1586                 goto out;
1587
1588         fh = fc_frame_header_get(fp);
1589         /*
1590          * BUG? fc_fcp_srr_error calls exch_done which would release
1591          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1592          * then fc_exch_timeout would be sending an abort. The exch_done
1593          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1594          * an abort response though.
1595          */
1596         if (fh->fh_type == FC_TYPE_BLS) {
1597                 fc_fcp_unlock_pkt(fsp);
1598                 return;
1599         }
1600
1601         fsp->recov_seq = NULL;
1602         switch (fc_frame_payload_op(fp)) {
1603         case ELS_LS_ACC:
1604                 fsp->recov_retry = 0;
1605                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1606                 break;
1607         case ELS_LS_RJT:
1608         default:
1609                 fc_timeout_error(fsp);
1610                 break;
1611         }
1612         fc_fcp_unlock_pkt(fsp);
1613         fsp->lp->tt.exch_done(seq);
1614 out:
1615         fc_frame_free(fp);
1616         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1617 }
1618
1619 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1620 {
1621         if (fc_fcp_lock_pkt(fsp))
1622                 goto out;
1623         fsp->lp->tt.exch_done(fsp->recov_seq);
1624         fsp->recov_seq = NULL;
1625         switch (PTR_ERR(fp)) {
1626         case -FC_EX_TIMEOUT:
1627                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1628                         fc_fcp_rec(fsp);
1629                 else
1630                         fc_timeout_error(fsp);
1631                 break;
1632         case -FC_EX_CLOSED:                     /* e.g., link failure */
1633                 /* fall through */
1634         default:
1635                 fc_fcp_retry_cmd(fsp);
1636                 break;
1637         }
1638         fc_fcp_unlock_pkt(fsp);
1639 out:
1640         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1641 }
1642
1643 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1644 {
1645         /* lock ? */
1646         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1647 }
1648
1649 /**
1650  * fc_queuecommand - The queuecommand function of the scsi template
1651  * @cmd:        struct scsi_cmnd to be executed
1652  * @done:       Callback function to be called when cmd is completed
1653  *
1654  * this is the i/o strategy routine, called by the scsi layer
1655  * this routine is called with holding the host_lock.
1656  */
1657 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1658 {
1659         struct fc_lport *lp;
1660         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1661         struct fc_fcp_pkt *fsp;
1662         struct fc_rport_libfc_priv *rp;
1663         int rval;
1664         int rc = 0;
1665         struct fcoe_dev_stats *stats;
1666
1667         lp = shost_priv(sc_cmd->device->host);
1668
1669         rval = fc_remote_port_chkready(rport);
1670         if (rval) {
1671                 sc_cmd->result = rval;
1672                 done(sc_cmd);
1673                 goto out;
1674         }
1675
1676         if (!*(struct fc_remote_port **)rport->dd_data) {
1677                 /*
1678                  * rport is transitioning from blocked/deleted to
1679                  * online
1680                  */
1681                 sc_cmd->result = DID_IMM_RETRY << 16;
1682                 done(sc_cmd);
1683                 goto out;
1684         }
1685
1686         rp = rport->dd_data;
1687
1688         if (!fc_fcp_lport_queue_ready(lp)) {
1689                 rc = SCSI_MLQUEUE_HOST_BUSY;
1690                 goto out;
1691         }
1692
1693         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1694         if (fsp == NULL) {
1695                 rc = SCSI_MLQUEUE_HOST_BUSY;
1696                 goto out;
1697         }
1698
1699         /*
1700          * build the libfc request pkt
1701          */
1702         fsp->cmd = sc_cmd;      /* save the cmd */
1703         fsp->lp = lp;           /* save the softc ptr */
1704         fsp->rport = rport;     /* set the remote port ptr */
1705         fsp->xfer_ddp = FC_XID_UNKNOWN;
1706         sc_cmd->scsi_done = done;
1707
1708         /*
1709          * set up the transfer length
1710          */
1711         fsp->data_len = scsi_bufflen(sc_cmd);
1712         fsp->xfer_len = 0;
1713
1714         /*
1715          * setup the data direction
1716          */
1717         stats = fc_lport_get_stats(lp);
1718         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1719                 fsp->req_flags = FC_SRB_READ;
1720                 stats->InputRequests++;
1721                 stats->InputMegabytes = fsp->data_len;
1722         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1723                 fsp->req_flags = FC_SRB_WRITE;
1724                 stats->OutputRequests++;
1725                 stats->OutputMegabytes = fsp->data_len;
1726         } else {
1727                 fsp->req_flags = 0;
1728                 stats->ControlRequests++;
1729         }
1730
1731         fsp->tgt_flags = rp->flags;
1732
1733         init_timer(&fsp->timer);
1734         fsp->timer.data = (unsigned long)fsp;
1735
1736         /*
1737          * send it to the lower layer
1738          * if we get -1 return then put the request in the pending
1739          * queue.
1740          */
1741         rval = fc_fcp_pkt_send(lp, fsp);
1742         if (rval != 0) {
1743                 fsp->state = FC_SRB_FREE;
1744                 fc_fcp_pkt_release(fsp);
1745                 rc = SCSI_MLQUEUE_HOST_BUSY;
1746         }
1747 out:
1748         return rc;
1749 }
1750 EXPORT_SYMBOL(fc_queuecommand);
1751
1752 /**
1753  * fc_io_compl() -  Handle responses for completed commands
1754  * @fsp:        scsi packet
1755  *
1756  * Translates a error to a Linux SCSI error.
1757  *
1758  * The fcp packet lock must be held when calling.
1759  */
1760 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1761 {
1762         struct fc_fcp_internal *si;
1763         struct scsi_cmnd *sc_cmd;
1764         struct fc_lport *lp;
1765         unsigned long flags;
1766
1767         /* release outstanding ddp context */
1768         fc_fcp_ddp_done(fsp);
1769
1770         fsp->state |= FC_SRB_COMPL;
1771         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1772                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1773                 del_timer_sync(&fsp->timer);
1774                 spin_lock_bh(&fsp->scsi_pkt_lock);
1775         }
1776
1777         lp = fsp->lp;
1778         si = fc_get_scsi_internal(lp);
1779         spin_lock_irqsave(lp->host->host_lock, flags);
1780         if (!fsp->cmd) {
1781                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1782                 return;
1783         }
1784
1785         /*
1786          * if a command timed out while we had to try and throttle IO
1787          * and it is now getting cleaned up, then we are about to
1788          * try again so clear the throttled flag incase we get more
1789          * time outs.
1790          */
1791         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1792                 si->throttled = 0;
1793
1794         sc_cmd = fsp->cmd;
1795         fsp->cmd = NULL;
1796
1797         if (!sc_cmd->SCp.ptr) {
1798                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1799                 return;
1800         }
1801
1802         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1803         switch (fsp->status_code) {
1804         case FC_COMPLETE:
1805                 if (fsp->cdb_status == 0) {
1806                         /*
1807                          * good I/O status
1808                          */
1809                         sc_cmd->result = DID_OK << 16;
1810                         if (fsp->scsi_resid)
1811                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1812                 } else {
1813                         /*
1814                          * transport level I/O was ok but scsi
1815                          * has non zero status
1816                          */
1817                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1818                 }
1819                 break;
1820         case FC_ERROR:
1821                 sc_cmd->result = DID_ERROR << 16;
1822                 break;
1823         case FC_DATA_UNDRUN:
1824                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1825                         /*
1826                          * scsi status is good but transport level
1827                          * underrun.
1828                          */
1829                         sc_cmd->result = (fsp->state & FC_SRB_RCV_STATUS ?
1830                                           DID_OK : DID_ERROR) << 16;
1831                 } else {
1832                         /*
1833                          * scsi got underrun, this is an error
1834                          */
1835                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1836                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1837                 }
1838                 break;
1839         case FC_DATA_OVRRUN:
1840                 /*
1841                  * overrun is an error
1842                  */
1843                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1844                 break;
1845         case FC_CMD_ABORTED:
1846                 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1847                 break;
1848         case FC_CMD_TIME_OUT:
1849                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1850                 break;
1851         case FC_CMD_RESET:
1852                 sc_cmd->result = (DID_RESET << 16);
1853                 break;
1854         case FC_HRD_ERROR:
1855                 sc_cmd->result = (DID_NO_CONNECT << 16);
1856                 break;
1857         default:
1858                 sc_cmd->result = (DID_ERROR << 16);
1859                 break;
1860         }
1861
1862         list_del(&fsp->list);
1863         sc_cmd->SCp.ptr = NULL;
1864         sc_cmd->scsi_done(sc_cmd);
1865         spin_unlock_irqrestore(lp->host->host_lock, flags);
1866
1867         /* release ref from initial allocation in queue command */
1868         fc_fcp_pkt_release(fsp);
1869 }
1870
1871 /**
1872  * fc_eh_abort() - Abort a command
1873  * @sc_cmd:     scsi command to abort
1874  *
1875  * From scsi host template.
1876  * send ABTS to the target device  and wait for the response
1877  * sc_cmd is the pointer to the command to be aborted.
1878  */
1879 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1880 {
1881         struct fc_fcp_pkt *fsp;
1882         struct fc_lport *lp;
1883         int rc = FAILED;
1884         unsigned long flags;
1885
1886         lp = shost_priv(sc_cmd->device->host);
1887         if (lp->state != LPORT_ST_READY)
1888                 return rc;
1889         else if (!lp->link_up)
1890                 return rc;
1891
1892         spin_lock_irqsave(lp->host->host_lock, flags);
1893         fsp = CMD_SP(sc_cmd);
1894         if (!fsp) {
1895                 /* command completed while scsi eh was setting up */
1896                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1897                 return SUCCESS;
1898         }
1899         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1900         fc_fcp_pkt_hold(fsp);
1901         spin_unlock_irqrestore(lp->host->host_lock, flags);
1902
1903         if (fc_fcp_lock_pkt(fsp)) {
1904                 /* completed while we were waiting for timer to be deleted */
1905                 rc = SUCCESS;
1906                 goto release_pkt;
1907         }
1908
1909         rc = fc_fcp_pkt_abort(fsp);
1910         fc_fcp_unlock_pkt(fsp);
1911
1912 release_pkt:
1913         fc_fcp_pkt_release(fsp);
1914         return rc;
1915 }
1916 EXPORT_SYMBOL(fc_eh_abort);
1917
1918 /**
1919  * fc_eh_device_reset() Reset a single LUN
1920  * @sc_cmd:     scsi command
1921  *
1922  * Set from scsi host template to send tm cmd to the target and wait for the
1923  * response.
1924  */
1925 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1926 {
1927         struct fc_lport *lp;
1928         struct fc_fcp_pkt *fsp;
1929         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1930         int rc = FAILED;
1931         struct fc_rport_libfc_priv *rp;
1932         int rval;
1933
1934         rval = fc_remote_port_chkready(rport);
1935         if (rval)
1936                 goto out;
1937
1938         rp = rport->dd_data;
1939         lp = shost_priv(sc_cmd->device->host);
1940
1941         if (lp->state != LPORT_ST_READY)
1942                 return rc;
1943
1944         FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id);
1945
1946         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
1947         if (fsp == NULL) {
1948                 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
1949                 sc_cmd->result = DID_NO_CONNECT << 16;
1950                 goto out;
1951         }
1952
1953         /*
1954          * Build the libfc request pkt. Do not set the scsi cmnd, because
1955          * the sc passed in is not setup for execution like when sent
1956          * through the queuecommand callout.
1957          */
1958         fsp->lp = lp;           /* save the softc ptr */
1959         fsp->rport = rport;     /* set the remote port ptr */
1960
1961         /*
1962          * flush outstanding commands
1963          */
1964         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
1965         fsp->state = FC_SRB_FREE;
1966         fc_fcp_pkt_release(fsp);
1967
1968 out:
1969         return rc;
1970 }
1971 EXPORT_SYMBOL(fc_eh_device_reset);
1972
1973 /**
1974  * fc_eh_host_reset() - The reset function will reset the ports on the host.
1975  * @sc_cmd:     scsi command
1976  */
1977 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
1978 {
1979         struct Scsi_Host *shost = sc_cmd->device->host;
1980         struct fc_lport *lp = shost_priv(shost);
1981         unsigned long wait_tmo;
1982
1983         FC_SCSI_DBG(lp, "Resetting host\n");
1984
1985         lp->tt.lport_reset(lp);
1986         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
1987         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
1988                 msleep(1000);
1989
1990         if (fc_fcp_lport_queue_ready(lp)) {
1991                 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
1992                              "on port (%6x)\n", fc_host_port_id(lp->host));
1993                 return SUCCESS;
1994         } else {
1995                 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
1996                              "port (%6x) is not ready.\n",
1997                              fc_host_port_id(lp->host));
1998                 return FAILED;
1999         }
2000 }
2001 EXPORT_SYMBOL(fc_eh_host_reset);
2002
2003 /**
2004  * fc_slave_alloc() - configure queue depth
2005  * @sdev:       scsi device
2006  *
2007  * Configures queue depth based on host's cmd_per_len. If not set
2008  * then we use the libfc default.
2009  */
2010 int fc_slave_alloc(struct scsi_device *sdev)
2011 {
2012         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2013
2014         if (!rport || fc_remote_port_chkready(rport))
2015                 return -ENXIO;
2016
2017         if (sdev->tagged_supported)
2018                 scsi_activate_tcq(sdev, FC_FCP_DFLT_QUEUE_DEPTH);
2019         else
2020                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev),
2021                                         FC_FCP_DFLT_QUEUE_DEPTH);
2022
2023         return 0;
2024 }
2025 EXPORT_SYMBOL(fc_slave_alloc);
2026
2027 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth, int reason)
2028 {
2029         switch (reason) {
2030         case SCSI_QDEPTH_DEFAULT:
2031                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2032                 break;
2033         case SCSI_QDEPTH_QFULL:
2034                 scsi_track_queue_full(sdev, qdepth);
2035                 break;
2036         case SCSI_QDEPTH_RAMP_UP:
2037                 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2038                 break;
2039         default:
2040                 return -EOPNOTSUPP;
2041         }
2042         return sdev->queue_depth;
2043 }
2044 EXPORT_SYMBOL(fc_change_queue_depth);
2045
2046 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2047 {
2048         if (sdev->tagged_supported) {
2049                 scsi_set_tag_type(sdev, tag_type);
2050                 if (tag_type)
2051                         scsi_activate_tcq(sdev, sdev->queue_depth);
2052                 else
2053                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2054         } else
2055                 tag_type = 0;
2056
2057         return tag_type;
2058 }
2059 EXPORT_SYMBOL(fc_change_queue_type);
2060
2061 void fc_fcp_destroy(struct fc_lport *lp)
2062 {
2063         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2064
2065         if (!list_empty(&si->scsi_pkt_queue))
2066                 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2067                        "port (%6x)\n", fc_host_port_id(lp->host));
2068
2069         mempool_destroy(si->scsi_pkt_pool);
2070         kfree(si);
2071         lp->scsi_priv = NULL;
2072 }
2073 EXPORT_SYMBOL(fc_fcp_destroy);
2074
2075 int fc_fcp_init(struct fc_lport *lp)
2076 {
2077         int rc;
2078         struct fc_fcp_internal *si;
2079
2080         if (!lp->tt.fcp_cmd_send)
2081                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2082
2083         if (!lp->tt.fcp_cleanup)
2084                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2085
2086         if (!lp->tt.fcp_abort_io)
2087                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2088
2089         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2090         if (!si)
2091                 return -ENOMEM;
2092         lp->scsi_priv = si;
2093         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2094
2095         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2096         if (!si->scsi_pkt_pool) {
2097                 rc = -ENOMEM;
2098                 goto free_internal;
2099         }
2100         return 0;
2101
2102 free_internal:
2103         kfree(si);
2104         return rc;
2105 }
2106 EXPORT_SYMBOL(fc_fcp_init);
2107
2108 static int __init libfc_init(void)
2109 {
2110         int rc;
2111
2112         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2113                                             sizeof(struct fc_fcp_pkt),
2114                                             0, SLAB_HWCACHE_ALIGN, NULL);
2115         if (scsi_pkt_cachep == NULL) {
2116                 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2117                        "module load failed!");
2118                 return -ENOMEM;
2119         }
2120
2121         rc = fc_setup_exch_mgr();
2122         if (rc)
2123                 goto destroy_pkt_cache;
2124
2125         rc = fc_setup_rport();
2126         if (rc)
2127                 goto destroy_em;
2128
2129         return rc;
2130 destroy_em:
2131         fc_destroy_exch_mgr();
2132 destroy_pkt_cache:
2133         kmem_cache_destroy(scsi_pkt_cachep);
2134         return rc;
2135 }
2136
2137 static void __exit libfc_exit(void)
2138 {
2139         kmem_cache_destroy(scsi_pkt_cachep);
2140         fc_destroy_exch_mgr();
2141         fc_destroy_rport();
2142 }
2143
2144 module_init(libfc_init);
2145 module_exit(libfc_exit);