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

   1 /*
   2  * Copyright(c) 2007 Intel Corporation. All rights reserved.
   3  * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
   4  * Copyright(c) 2008 Mike Christie
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Maintained at www.Open-FCoE.org
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/delay.h>
  24 #include <linux/kernel.h>
  25 #include <linux/types.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/scatterlist.h>
  28 #include <linux/err.h>
  29 #include <linux/crc32.h>
  30
  31 #include <scsi/scsi_tcq.h>
  32 #include <scsi/scsi.h>
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi_device.h>
  35 #include <scsi/scsi_cmnd.h>
  36
  37 #include <scsi/fc/fc_fc2.h>
  38
  39 #include <scsi/libfc.h>
  40 #include <scsi/fc_encode.h>
  41
  42 MODULE_AUTHOR("Open-FCoE.org");
  43 MODULE_DESCRIPTION("libfc");
  44 MODULE_LICENSE("GPL");
  45
  46 static int fc_fcp_debug;
  47
  48 #define FC_DEBUG_FCP(fmt...)                    \
  49         do {                                    \
  50                 if (fc_fcp_debug)               \
  51                         FC_DBG(fmt);            \
  52         } while (0)
  53
  54 static struct kmem_cache *scsi_pkt_cachep;
  55
  56 /* SRB state definitions */
  57 #define FC_SRB_FREE             0               /* cmd is free */
  58 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
  59 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
  60 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
  61 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
  62 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
  63 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
  64 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
  65 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
  66
  67 #define FC_SRB_READ             (1 << 1)
  68 #define FC_SRB_WRITE            (1 << 0)
  69
  70 /*
  71  * The SCp.ptr should be tested and set under the host lock. NULL indicates
  72  * that the command has been retruned to the scsi layer.
  73  */
  74 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
  75 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
  76 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
  77 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
  78 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
  79
  80 struct fc_fcp_internal {
  81         mempool_t       *scsi_pkt_pool;
  82         struct list_head scsi_pkt_queue;
  83         u8              throttled;
  84 };
  85
  86 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
  87
  88 /*
  89  * function prototypes
  90  * FC scsi I/O related functions
  91  */
  92 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
  93 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
  94 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
  95 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
  96 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
  97 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
  98 static void fc_timeout_error(struct fc_fcp_pkt *);
  99 static void fc_fcp_timeout(unsigned long data);
 100 static void fc_fcp_rec(struct fc_fcp_pkt *);
 101 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
 102 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
 103 static void fc_io_compl(struct fc_fcp_pkt *);
 104
 105 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
 106 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
 107 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
 108
 109 /*
 110  * command status codes
 111  */
 112 #define FC_COMPLETE             0
 113 #define FC_CMD_ABORTED          1
 114 #define FC_CMD_RESET            2
 115 #define FC_CMD_PLOGO            3
 116 #define FC_SNS_RCV              4
 117 #define FC_TRANS_ERR            5
 118 #define FC_DATA_OVRRUN          6
 119 #define FC_DATA_UNDRUN          7
 120 #define FC_ERROR                8
 121 #define FC_HRD_ERROR            9
 122 #define FC_CMD_TIME_OUT         10
 123
 124 /*
 125  * Error recovery timeout values.
 126  */
 127 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 128 #define FC_SCSI_TM_TOV          (10 * HZ)
 129 #define FC_SCSI_REC_TOV         (2 * HZ)
 130 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 131
 132 #define FC_MAX_ERROR_CNT        5
 133 #define FC_MAX_RECOV_RETRY      3
 134
 135 #define FC_FCP_DFLT_QUEUE_DEPTH 32
 136
 137 /**
 138  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 139  * @lp:         fc lport struct
 140  * @gfp:        gfp flags for allocation
 141  *
 142  * This is used by upper layer scsi driver.
 143  * Return Value : scsi_pkt structure or null on allocation failure.
 144  * Context      : call from process context. no locking required.
 145  */
 146 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
 147 {
 148         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 149         struct fc_fcp_pkt *fsp;
 150
 151         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
 152         if (fsp) {
 153                 memset(fsp, 0, sizeof(*fsp));
 154                 fsp->lp = lp;
 155                 atomic_set(&fsp->ref_cnt, 1);
 156                 init_timer(&fsp->timer);
 157                 INIT_LIST_HEAD(&fsp->list);
 158                 spin_lock_init(&fsp->scsi_pkt_lock);
 159         }
 160         return fsp;
 161 }
 162
 163 /**
 164  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
 165  * @fsp:        fcp packet struct
 166  *
 167  * This is used by upper layer scsi driver.
 168  * Context      : call from process  and interrupt context.
 169  *                no locking required
 170  */
 171 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
 172 {
 173         if (atomic_dec_and_test(&fsp->ref_cnt)) {
 174                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
 175
 176                 mempool_free(fsp, si->scsi_pkt_pool);
 177         }
 178 }
 179
 180 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
 181 {
 182         atomic_inc(&fsp->ref_cnt);
 183 }
 184
 185 /**
 186  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
 187  * @seq:                exchange sequence
 188  * @fsp:        fcp packet struct
 189  *
 190  * Release hold on scsi_pkt packet set to keep scsi_pkt
 191  * till EM layer exch resource is not freed.
 192  * Context      : called from from EM layer.
 193  *                no locking required
 194  */
 195 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
 196 {
 197         fc_fcp_pkt_release(fsp);
 198 }
 199
 200 /**
 201  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
 202  * @fsp:        fcp packet
 203  *
 204  * We should only return error if we return a command to scsi-ml before
 205  * getting a response. This can happen in cases where we send a abort, but
 206  * do not wait for the response and the abort and command can be passing
 207  * each other on the wire/network-layer.
 208  *
 209  * Note: this function locks the packet and gets a reference to allow
 210  * callers to call the completion function while the lock is held and
 211  * not have to worry about the packets refcount.
 212  *
 213  * TODO: Maybe we should just have callers grab/release the lock and
 214  * have a function that they call to verify the fsp and grab a ref if
 215  * needed.
 216  */
 217 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
 218 {
 219         spin_lock_bh(&fsp->scsi_pkt_lock);
 220         if (fsp->state & FC_SRB_COMPL) {
 221                 spin_unlock_bh(&fsp->scsi_pkt_lock);
 222                 return -EPERM;
 223         }
 224
 225         fc_fcp_pkt_hold(fsp);
 226         return 0;
 227 }
 228
 229 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
 230 {
 231         spin_unlock_bh(&fsp->scsi_pkt_lock);
 232         fc_fcp_pkt_release(fsp);
 233 }
 234
 235 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
 236 {
 237         if (!(fsp->state & FC_SRB_COMPL))
 238                 mod_timer(&fsp->timer, jiffies + delay);
 239 }
 240
 241 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 242 {
 243         if (!fsp->seq_ptr)
 244                 return -EINVAL;
 245
 246         fsp->state |= FC_SRB_ABORT_PENDING;
 247         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 248 }
 249
 250 /*
 251  * Retry command.
 252  * An abort isn't needed.
 253  */
 254 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
 255 {
 256         if (fsp->seq_ptr) {
 257                 fsp->lp->tt.exch_done(fsp->seq_ptr);
 258                 fsp->seq_ptr = NULL;
 259         }
 260
 261         fsp->state &= ~FC_SRB_ABORT_PENDING;
 262         fsp->io_status = 0;
 263         fsp->status_code = FC_ERROR;
 264         fc_fcp_complete_locked(fsp);
 265 }
 266
 267 /*
 268  * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
 269  * transfer for a read I/O indicated by the fc_fcp_pkt.
 270  * @fsp: ptr to the fc_fcp_pkt
 271  *
 272  * This is called in exch_seq_send() when we have a newly allocated
 273  * exchange with a valid exchange id to setup ddp.
 274  *
 275  * returns: none
 276  */
 277 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
 278 {
 279         struct fc_lport *lp;
 280
 281         if (!fsp)
 282                 return;
 283
 284         lp = fsp->lp;
 285         if ((fsp->req_flags & FC_SRB_READ) &&
 286             (lp->lro_enabled) && (lp->tt.ddp_setup)) {
 287                 if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
 288                                      scsi_sg_count(fsp->cmd)))
 289                         fsp->xfer_ddp = xid;
 290         }
 291 }
 292 EXPORT_SYMBOL(fc_fcp_ddp_setup);
 293
 294 /*
 295  * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
 296  * DDP related resources for this I/O if it is initialized
 297  * as a ddp transfer
 298  * @fsp: ptr to the fc_fcp_pkt
 299  *
 300  * returns: none
 301  */
 302 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
 303 {
 304         struct fc_lport *lp;
 305
 306         if (!fsp)
 307                 return;
 308
 309         lp = fsp->lp;
 310         if (fsp->xfer_ddp && lp->tt.ddp_done) {
 311                 fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
 312                 fsp->xfer_ddp = 0;
 313         }
 314 }
 315
 316
 317 /*
 318  * Receive SCSI data from target.
 319  * Called after receiving solicited data.
 320  */
 321 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 322 {
 323         struct scsi_cmnd *sc = fsp->cmd;
 324         struct fc_lport *lp = fsp->lp;
 325         struct fcoe_dev_stats *stats;
 326         struct fc_frame_header *fh;
 327         size_t start_offset;
 328         size_t offset;
 329         u32 crc;
 330         u32 copy_len = 0;
 331         size_t len;
 332         void *buf;
 333         struct scatterlist *sg;
 334         size_t remaining;
 335
 336         fh = fc_frame_header_get(fp);
 337         offset = ntohl(fh->fh_parm_offset);
 338         start_offset = offset;
 339         len = fr_len(fp) - sizeof(*fh);
 340         buf = fc_frame_payload_get(fp, 0);
 341
 342         /* if this I/O is ddped, update xfer len */
 343         fc_fcp_ddp_done(fsp);
 344
 345         if (offset + len > fsp->data_len) {
 346                 /* this should never happen */
 347                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
 348                     fc_frame_crc_check(fp))
 349                         goto crc_err;
 350                 FC_DEBUG_FCP("data received past end. len %zx offset %zx "
 351                              "data_len %x\n", len, offset, fsp->data_len);
 352                 fc_fcp_retry_cmd(fsp);
 353                 return;
 354         }
 355         if (offset != fsp->xfer_len)
 356                 fsp->state |= FC_SRB_DISCONTIG;
 357
 358         crc = 0;
 359         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 360                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
 361
 362         sg = scsi_sglist(sc);
 363         remaining = len;
 364
 365         while (remaining > 0 && sg) {
 366                 size_t off;
 367                 void *page_addr;
 368                 size_t sg_bytes;
 369
 370                 if (offset >= sg->length) {
 371                         offset -= sg->length;
 372                         sg = sg_next(sg);
 373                         continue;
 374                 }
 375                 sg_bytes = min(remaining, sg->length - offset);
 376
 377                 /*
 378                  * The scatterlist item may be bigger than PAGE_SIZE,
 379                  * but we are limited to mapping PAGE_SIZE at a time.
 380                  */
 381                 off = offset + sg->offset;
 382                 sg_bytes = min(sg_bytes, (size_t)
 383                                (PAGE_SIZE - (off & ~PAGE_MASK)));
 384                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
 385                                         KM_SOFTIRQ0);
 386                 if (!page_addr)
 387                         break;          /* XXX panic? */
 388
 389                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 390                         crc = crc32(crc, buf, sg_bytes);
 391                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
 392                        sg_bytes);
 393
 394                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
 395                 buf += sg_bytes;
 396                 offset += sg_bytes;
 397                 remaining -= sg_bytes;
 398                 copy_len += sg_bytes;
 399         }
 400
 401         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
 402                 buf = fc_frame_payload_get(fp, 0);
 403                 if (len % 4) {
 404                         crc = crc32(crc, buf + len, 4 - (len % 4));
 405                         len += 4 - (len % 4);
 406                 }
 407
 408                 if (~crc != le32_to_cpu(fr_crc(fp))) {
 409 crc_err:
 410                         stats = lp->dev_stats[smp_processor_id()];
 411                         stats->ErrorFrames++;
 412                         if (stats->InvalidCRCCount++ < 5)
 413                                 FC_DBG("CRC error on data frame\n");
 414                         /*
 415                          * Assume the frame is total garbage.
 416                          * We may have copied it over the good part
 417                          * of the buffer.
 418                          * If so, we need to retry the entire operation.
 419                          * Otherwise, ignore it.
 420                          */
 421                         if (fsp->state & FC_SRB_DISCONTIG)
 422                                 fc_fcp_retry_cmd(fsp);
 423                         return;
 424                 }
 425         }
 426
 427         if (fsp->xfer_contig_end == start_offset)
 428                 fsp->xfer_contig_end += copy_len;
 429         fsp->xfer_len += copy_len;
 430
 431         /*
 432          * In the very rare event that this data arrived after the response
 433          * and completes the transfer, call the completion handler.
 434          */
 435         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
 436             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
 437                 fc_fcp_complete_locked(fsp);
 438 }
 439
 440 /**
 441  * fc_fcp_send_data() -  Send SCSI data to target.
 442  * @fsp: ptr to fc_fcp_pkt
 443  * @sp: ptr to this sequence
 444  * @offset: starting offset for this data request
 445  * @seq_blen: the burst length for this data request
 446  *
 447  * Called after receiving a Transfer Ready data descriptor.
 448  * if LLD is capable of seq offload then send down seq_blen
 449  * size of data in single frame, otherwise send multiple FC
 450  * frames of max FC frame payload supported by target port.
 451  *
 452  * Returns : 0 for success.
 453  */
 454 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
 455                             size_t offset, size_t seq_blen)
 456 {
 457         struct fc_exch *ep;
 458         struct scsi_cmnd *sc;
 459         struct scatterlist *sg;
 460         struct fc_frame *fp = NULL;
 461         struct fc_lport *lp = fsp->lp;
 462         size_t remaining;
 463         size_t t_blen;
 464         size_t tlen;
 465         size_t sg_bytes;
 466         size_t frame_offset, fh_parm_offset;
 467         int error;
 468         void *data = NULL;
 469         void *page_addr;
 470         int using_sg = lp->sg_supp;
 471         u32 f_ctl;
 472
 473         WARN_ON(seq_blen <= 0);
 474         if (unlikely(offset + seq_blen > fsp->data_len)) {
 475                 /* this should never happen */
 476                 FC_DEBUG_FCP("xfer-ready past end. seq_blen %zx offset %zx\n",
 477                              seq_blen, offset);
 478                 fc_fcp_send_abort(fsp);
 479                 return 0;
 480         } else if (offset != fsp->xfer_len) {
 481                 /* Out of Order Data Request - no problem, but unexpected. */
 482                 FC_DEBUG_FCP("xfer-ready non-contiguous. "
 483                              "seq_blen %zx offset %zx\n", seq_blen, offset);
 484         }
 485
 486         /*
 487          * if LLD is capable of seq_offload then set transport
 488          * burst length (t_blen) to seq_blen, otherwise set t_blen
 489          * to max FC frame payload previously set in fsp->max_payload.
 490          */
 491         t_blen = fsp->max_payload;
 492         if (lp->seq_offload) {
 493                 t_blen = min(seq_blen, (size_t)lp->lso_max);
 494                 FC_DEBUG_FCP("fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
 495                            fsp, seq_blen, lp->lso_max, t_blen);
 496         }
 497
 498         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
 499         if (t_blen > 512)
 500                 t_blen &= ~(512 - 1);   /* round down to block size */
 501         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
 502         sc = fsp->cmd;
 503
 504         remaining = seq_blen;
 505         fh_parm_offset = frame_offset = offset;
 506         tlen = 0;
 507         seq = lp->tt.seq_start_next(seq);
 508         f_ctl = FC_FC_REL_OFF;
 509         WARN_ON(!seq);
 510
 511         /*
 512          * If a get_page()/put_page() will fail, don't use sg lists
 513          * in the fc_frame structure.
 514          *
 515          * The put_page() may be long after the I/O has completed
 516          * in the case of FCoE, since the network driver does it
 517          * via free_skb().  See the test in free_pages_check().
 518          *
 519          * Test this case with 'dd </dev/zero >/dev/st0 bs=64k'.
 520          */
 521         if (using_sg) {
 522                 for (sg = scsi_sglist(sc); sg; sg = sg_next(sg)) {
 523                         if (page_count(sg_page(sg)) == 0 ||
 524                             (sg_page(sg)->flags & (1 << PG_lru |
 525                                                    1 << PG_private |
 526                                                    1 << PG_locked |
 527                                                    1 << PG_active |
 528                                                    1 << PG_slab |
 529                                                    1 << PG_swapcache |
 530                                                    1 << PG_writeback |
 531                                                    1 << PG_reserved |
 532                                                    1 << PG_buddy))) {
 533                                 using_sg = 0;
 534                                 break;
 535                         }
 536                 }
 537         }
 538         sg = scsi_sglist(sc);
 539
 540         while (remaining > 0 && sg) {
 541                 if (offset >= sg->length) {
 542                         offset -= sg->length;
 543                         sg = sg_next(sg);
 544                         continue;
 545                 }
 546                 if (!fp) {
 547                         tlen = min(t_blen, remaining);
 548
 549                         /*
 550                          * TODO.  Temporary workaround.  fc_seq_send() can't
 551                          * handle odd lengths in non-linear skbs.
 552                          * This will be the final fragment only.
 553                          */
 554                         if (tlen % 4)
 555                                 using_sg = 0;
 556                         if (using_sg) {
 557                                 fp = _fc_frame_alloc(lp, 0);
 558                                 if (!fp)
 559                                         return -ENOMEM;
 560                         } else {
 561                                 fp = fc_frame_alloc(lp, tlen);
 562                                 if (!fp)
 563                                         return -ENOMEM;
 564
 565                                 data = (void *)(fr_hdr(fp)) +
 566                                         sizeof(struct fc_frame_header);
 567                         }
 568                         fh_parm_offset = frame_offset;
 569                         fr_max_payload(fp) = fsp->max_payload;
 570                 }
 571                 sg_bytes = min(tlen, sg->length - offset);
 572                 if (using_sg) {
 573                         WARN_ON(skb_shinfo(fp_skb(fp))->nr_frags >
 574                                 FC_FRAME_SG_LEN);
 575                         get_page(sg_page(sg));
 576                         skb_fill_page_desc(fp_skb(fp),
 577                                            skb_shinfo(fp_skb(fp))->nr_frags,
 578                                            sg_page(sg), sg->offset + offset,
 579                                            sg_bytes);
 580                         fp_skb(fp)->data_len += sg_bytes;
 581                         fr_len(fp) += sg_bytes;
 582                         fp_skb(fp)->truesize += PAGE_SIZE;
 583                 } else {
 584                         size_t off = offset + sg->offset;
 585
 586                         /*
 587                          * The scatterlist item may be bigger than PAGE_SIZE,
 588                          * but we must not cross pages inside the kmap.
 589                          */
 590                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
 591                                                            (off & ~PAGE_MASK)));
 592                         page_addr = kmap_atomic(sg_page(sg) +
 593                                                 (off >> PAGE_SHIFT),
 594                                                 KM_SOFTIRQ0);
 595                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
 596                                sg_bytes);
 597                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
 598                         data += sg_bytes;
 599                 }
 600                 offset += sg_bytes;
 601                 frame_offset += sg_bytes;
 602                 tlen -= sg_bytes;
 603                 remaining -= sg_bytes;
 604
 605                 if (tlen)
 606                         continue;
 607
 608                 /*
 609                  * Send sequence with transfer sequence initiative in case
 610                  * this is last FCP frame of the sequence.
 611                  */
 612                 if (remaining == 0)
 613                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
 614
 615                 ep = fc_seq_exch(seq);
 616                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
 617                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
 618
 619                 /*
 620                  * send fragment using for a sequence.
 621                  */
 622                 error = lp->tt.seq_send(lp, seq, fp);
 623                 if (error) {
 624                         WARN_ON(1);             /* send error should be rare */
 625                         fc_fcp_retry_cmd(fsp);
 626                         return 0;
 627                 }
 628                 fp = NULL;
 629         }
 630         fsp->xfer_len += seq_blen;      /* premature count? */
 631         return 0;
 632 }
 633
 634 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 635 {
 636         int ba_done = 1;
 637         struct fc_ba_rjt *brp;
 638         struct fc_frame_header *fh;
 639
 640         fh = fc_frame_header_get(fp);
 641         switch (fh->fh_r_ctl) {
 642         case FC_RCTL_BA_ACC:
 643                 break;
 644         case FC_RCTL_BA_RJT:
 645                 brp = fc_frame_payload_get(fp, sizeof(*brp));
 646                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
 647                         break;
 648                 /* fall thru */
 649         default:
 650                 /*
 651                  * we will let the command timeout
 652                  * and scsi-ml recover in this case,
 653                  * therefore cleared the ba_done flag.
 654                  */
 655                 ba_done = 0;
 656         }
 657
 658         if (ba_done) {
 659                 fsp->state |= FC_SRB_ABORTED;
 660                 fsp->state &= ~FC_SRB_ABORT_PENDING;
 661
 662                 if (fsp->wait_for_comp)
 663                         complete(&fsp->tm_done);
 664                 else
 665                         fc_fcp_complete_locked(fsp);
 666         }
 667 }
 668
 669 /**
 670  * fc_fcp_reduce_can_queue() - drop can_queue
 671  * @lp: lport to drop queueing for
 672  *
 673  * If we are getting memory allocation failures, then we may
 674  * be trying to execute too many commands. We let the running
 675  * commands complete or timeout, then try again with a reduced
 676  * can_queue. Eventually we will hit the point where we run
 677  * on all reserved structs.
 678  */
 679 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
 680 {
 681         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 682         unsigned long flags;
 683         int can_queue;
 684
 685         spin_lock_irqsave(lp->host->host_lock, flags);
 686         if (si->throttled)
 687                 goto done;
 688         si->throttled = 1;
 689
 690         can_queue = lp->host->can_queue;
 691         can_queue >>= 1;
 692         if (!can_queue)
 693                 can_queue = 1;
 694         lp->host->can_queue = can_queue;
 695         shost_printk(KERN_ERR, lp->host, "Could not allocate frame.\n"
 696                      "Reducing can_queue to %d.\n", can_queue);
 697 done:
 698         spin_unlock_irqrestore(lp->host->host_lock, flags);
 699 }
 700
 701 /**
 702  * fc_fcp_recv() - Reveive FCP frames
 703  * @seq: The sequence the frame is on
 704  * @fp: The FC frame
 705  * @arg: The related FCP packet
 706  *
 707  * Return   : None
 708  * Context  : called from Soft IRQ context
 709  *            can not called holding list lock
 710  */
 711 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 712 {
 713         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
 714         struct fc_lport *lp;
 715         struct fc_frame_header *fh;
 716         struct fcp_txrdy *dd;
 717         u8 r_ctl;
 718         int rc = 0;
 719
 720         if (IS_ERR(fp))
 721                 goto errout;
 722
 723         fh = fc_frame_header_get(fp);
 724         r_ctl = fh->fh_r_ctl;
 725         lp = fsp->lp;
 726
 727         if (!(lp->state & LPORT_ST_READY))
 728                 goto out;
 729         if (fc_fcp_lock_pkt(fsp))
 730                 goto out;
 731         fsp->last_pkt_time = jiffies;
 732
 733         if (fh->fh_type == FC_TYPE_BLS) {
 734                 fc_fcp_abts_resp(fsp, fp);
 735                 goto unlock;
 736         }
 737
 738         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
 739                 goto unlock;
 740
 741         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
 742                 /*
 743                  * received XFER RDY from the target
 744                  * need to send data to the target
 745                  */
 746                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 747                 dd = fc_frame_payload_get(fp, sizeof(*dd));
 748                 WARN_ON(!dd);
 749
 750                 rc = fc_fcp_send_data(fsp, seq,
 751                                       (size_t) ntohl(dd->ft_data_ro),
 752                                       (size_t) ntohl(dd->ft_burst_len));
 753                 if (!rc)
 754                         seq->rec_data = fsp->xfer_len;
 755                 else if (rc == -ENOMEM)
 756                         fsp->state |= FC_SRB_NOMEM;
 757         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
 758                 /*
 759                  * received a DATA frame
 760                  * next we will copy the data to the system buffer
 761                  */
 762                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
 763                 fc_fcp_recv_data(fsp, fp);
 764                 seq->rec_data = fsp->xfer_contig_end;
 765         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
 766                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 767
 768                 fc_fcp_resp(fsp, fp);
 769         } else {
 770                 FC_DBG("unexpected frame.  r_ctl %x\n", r_ctl);
 771         }
 772 unlock:
 773         fc_fcp_unlock_pkt(fsp);
 774 out:
 775         fc_frame_free(fp);
 776 errout:
 777         if (IS_ERR(fp))
 778                 fc_fcp_error(fsp, fp);
 779         else if (rc == -ENOMEM)
 780                 fc_fcp_reduce_can_queue(lp);
 781 }
 782
 783 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 784 {
 785         struct fc_frame_header *fh;
 786         struct fcp_resp *fc_rp;
 787         struct fcp_resp_ext *rp_ex;
 788         struct fcp_resp_rsp_info *fc_rp_info;
 789         u32 plen;
 790         u32 expected_len;
 791         u32 respl = 0;
 792         u32 snsl = 0;
 793         u8 flags = 0;
 794
 795         plen = fr_len(fp);
 796         fh = (struct fc_frame_header *)fr_hdr(fp);
 797         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
 798                 goto len_err;
 799         plen -= sizeof(*fh);
 800         fc_rp = (struct fcp_resp *)(fh + 1);
 801         fsp->cdb_status = fc_rp->fr_status;
 802         flags = fc_rp->fr_flags;
 803         fsp->scsi_comp_flags = flags;
 804         expected_len = fsp->data_len;
 805
 806         /* if ddp, update xfer len */
 807         fc_fcp_ddp_done(fsp);
 808
 809         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
 810                 rp_ex = (void *)(fc_rp + 1);
 811                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
 812                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
 813                                 goto len_err;
 814                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
 815                         if (flags & FCP_RSP_LEN_VAL) {
 816                                 respl = ntohl(rp_ex->fr_rsp_len);
 817                                 if (respl != sizeof(*fc_rp_info))
 818                                         goto len_err;
 819                                 if (fsp->wait_for_comp) {
 820                                         /* Abuse cdb_status for rsp code */
 821                                         fsp->cdb_status = fc_rp_info->rsp_code;
 822                                         complete(&fsp->tm_done);
 823                                         /*
 824                                          * tmfs will not have any scsi cmd so
 825                                          * exit here
 826                                          */
 827                                         return;
 828                                 } else
 829                                         goto err;
 830                         }
 831                         if (flags & FCP_SNS_LEN_VAL) {
 832                                 snsl = ntohl(rp_ex->fr_sns_len);
 833                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
 834                                         snsl = SCSI_SENSE_BUFFERSIZE;
 835                                 memcpy(fsp->cmd->sense_buffer,
 836                                        (char *)fc_rp_info + respl, snsl);
 837                         }
 838                 }
 839                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
 840                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
 841                                 goto len_err;
 842                         if (flags & FCP_RESID_UNDER) {
 843                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
 844                                 /*
 845                                  * The cmnd->underflow is the minimum number of
 846                                  * bytes that must be transfered for this
 847                                  * command.  Provided a sense condition is not
 848                                  * present, make sure the actual amount
 849                                  * transferred is at least the underflow value
 850                                  * or fail.
 851                                  */
 852                                 if (!(flags & FCP_SNS_LEN_VAL) &&
 853                                     (fc_rp->fr_status == 0) &&
 854                                     (scsi_bufflen(fsp->cmd) -
 855                                      fsp->scsi_resid) < fsp->cmd->underflow)
 856                                         goto err;
 857                                 expected_len -= fsp->scsi_resid;
 858                         } else {
 859                                 fsp->status_code = FC_ERROR;
 860                         }
 861                 }
 862         }
 863         fsp->state |= FC_SRB_RCV_STATUS;
 864
 865         /*
 866          * Check for missing or extra data frames.
 867          */
 868         if (unlikely(fsp->xfer_len != expected_len)) {
 869                 if (fsp->xfer_len < expected_len) {
 870                         /*
 871                          * Some data may be queued locally,
 872                          * Wait a at least one jiffy to see if it is delivered.
 873                          * If this expires without data, we may do SRR.
 874                          */
 875                         fc_fcp_timer_set(fsp, 2);
 876                         return;
 877                 }
 878                 fsp->status_code = FC_DATA_OVRRUN;
 879                 FC_DBG("tgt %6x xfer len %zx greater than expected len %x. "
 880                        "data len %x\n",
 881                        fsp->rport->port_id,
 882                        fsp->xfer_len, expected_len, fsp->data_len);
 883         }
 884         fc_fcp_complete_locked(fsp);
 885         return;
 886
 887 len_err:
 888         FC_DBG("short FCP response. flags 0x%x len %u respl %u snsl %u\n",
 889                flags, fr_len(fp), respl, snsl);
 890 err:
 891         fsp->status_code = FC_ERROR;
 892         fc_fcp_complete_locked(fsp);
 893 }
 894
 895 /**
 896  * fc_fcp_complete_locked() - complete processing of a fcp packet
 897  * @fsp:        fcp packet
 898  *
 899  * This function may sleep if a timer is pending. The packet lock must be
 900  * held, and the host lock must not be held.
 901  */
 902 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
 903 {
 904         struct fc_lport *lp = fsp->lp;
 905         struct fc_seq *seq;
 906         struct fc_exch *ep;
 907         u32 f_ctl;
 908
 909         if (fsp->state & FC_SRB_ABORT_PENDING)
 910                 return;
 911
 912         if (fsp->state & FC_SRB_ABORTED) {
 913                 if (!fsp->status_code)
 914                         fsp->status_code = FC_CMD_ABORTED;
 915         } else {
 916                 /*
 917                  * Test for transport underrun, independent of response
 918                  * underrun status.
 919                  */
 920                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
 921                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
 922                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
 923                         fsp->status_code = FC_DATA_UNDRUN;
 924                         fsp->io_status = 0;
 925                 }
 926         }
 927
 928         seq = fsp->seq_ptr;
 929         if (seq) {
 930                 fsp->seq_ptr = NULL;
 931                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
 932                         struct fc_frame *conf_frame;
 933                         struct fc_seq *csp;
 934
 935                         csp = lp->tt.seq_start_next(seq);
 936                         conf_frame = fc_frame_alloc(fsp->lp, 0);
 937                         if (conf_frame) {
 938                                 f_ctl = FC_FC_SEQ_INIT;
 939                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
 940                                 ep = fc_seq_exch(seq);
 941                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
 942                                                ep->did, ep->sid,
 943                                                FC_TYPE_FCP, f_ctl, 0);
 944                                 lp->tt.seq_send(lp, csp, conf_frame);
 945                         }
 946                 }
 947                 lp->tt.exch_done(seq);
 948         }
 949         fc_io_compl(fsp);
 950 }
 951
 952 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
 953 {
 954         struct fc_lport *lp = fsp->lp;
 955
 956         if (fsp->seq_ptr) {
 957                 lp->tt.exch_done(fsp->seq_ptr);
 958                 fsp->seq_ptr = NULL;
 959         }
 960         fsp->status_code = error;
 961 }
 962
 963 /**
 964  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
 965  * @lp:         logical port
 966  * @id:         target id
 967  * @lun:        lun
 968  * @error:      fsp status code
 969  *
 970  * If lun or id is -1, they are ignored.
 971  */
 972 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
 973                                     unsigned int lun, int error)
 974 {
 975         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 976         struct fc_fcp_pkt *fsp;
 977         struct scsi_cmnd *sc_cmd;
 978         unsigned long flags;
 979
 980         spin_lock_irqsave(lp->host->host_lock, flags);
 981 restart:
 982         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
 983                 sc_cmd = fsp->cmd;
 984                 if (id != -1 && scmd_id(sc_cmd) != id)
 985                         continue;
 986
 987                 if (lun != -1 && sc_cmd->device->lun != lun)
 988                         continue;
 989
 990                 fc_fcp_pkt_hold(fsp);
 991                 spin_unlock_irqrestore(lp->host->host_lock, flags);
 992
 993                 if (!fc_fcp_lock_pkt(fsp)) {
 994                         fc_fcp_cleanup_cmd(fsp, error);
 995                         fc_io_compl(fsp);
 996                         fc_fcp_unlock_pkt(fsp);
 997                 }
 998
 999                 fc_fcp_pkt_release(fsp);
1000                 spin_lock_irqsave(lp->host->host_lock, flags);
1001                 /*
1002                  * while we dropped the lock multiple pkts could
1003                  * have been released, so we have to start over.
1004                  */
1005                 goto restart;
1006         }
1007         spin_unlock_irqrestore(lp->host->host_lock, flags);
1008 }
1009
1010 static void fc_fcp_abort_io(struct fc_lport *lp)
1011 {
1012         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
1013 }
1014
1015 /**
1016  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
1017  * @lp:         fc lport
1018  * @fsp:        fc packet.
1019  *
1020  * This is called by upper layer protocol.
1021  * Return   : zero for success and -1 for failure
1022  * Context  : called from queuecommand which can be called from process
1023  *            or scsi soft irq.
1024  * Locks    : called with the host lock and irqs disabled.
1025  */
1026 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1027 {
1028         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
1029         int rc;
1030
1031         fsp->cmd->SCp.ptr = (char *)fsp;
1032         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1033         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1034
1035         int_to_scsilun(fsp->cmd->device->lun,
1036                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1037         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1038         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1039
1040         spin_unlock_irq(lp->host->host_lock);
1041         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
1042         spin_lock_irq(lp->host->host_lock);
1043         if (rc)
1044                 list_del(&fsp->list);
1045
1046         return rc;
1047 }
1048
1049 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1050                            void (*resp)(struct fc_seq *,
1051                                         struct fc_frame *fp,
1052                                         void *arg))
1053 {
1054         struct fc_frame *fp;
1055         struct fc_seq *seq;
1056         struct fc_rport *rport;
1057         struct fc_rport_libfc_priv *rp;
1058         const size_t len = sizeof(fsp->cdb_cmd);
1059         int rc = 0;
1060
1061         if (fc_fcp_lock_pkt(fsp))
1062                 return 0;
1063
1064         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1065         if (!fp) {
1066                 rc = -1;
1067                 goto unlock;
1068         }
1069
1070         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1071         fr_fsp(fp) = fsp;
1072         rport = fsp->rport;
1073         fsp->max_payload = rport->maxframe_size;
1074         rp = rport->dd_data;
1075
1076         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1077                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1078                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1079
1080         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1081         if (!seq) {
1082                 fc_frame_free(fp);
1083                 rc = -1;
1084                 goto unlock;
1085         }
1086         fsp->last_pkt_time = jiffies;
1087         fsp->seq_ptr = seq;
1088         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1089
1090         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1091         fc_fcp_timer_set(fsp,
1092                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1093                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1094 unlock:
1095         fc_fcp_unlock_pkt(fsp);
1096         return rc;
1097 }
1098
1099 /*
1100  * transport error handler
1101  */
1102 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1103 {
1104         int error = PTR_ERR(fp);
1105
1106         if (fc_fcp_lock_pkt(fsp))
1107                 return;
1108
1109         switch (error) {
1110         case -FC_EX_CLOSED:
1111                 fc_fcp_retry_cmd(fsp);
1112                 goto unlock;
1113         default:
1114                 FC_DBG("unknown error %ld\n", PTR_ERR(fp));
1115         }
1116         /*
1117          * clear abort pending, because the lower layer
1118          * decided to force completion.
1119          */
1120         fsp->state &= ~FC_SRB_ABORT_PENDING;
1121         fsp->status_code = FC_CMD_PLOGO;
1122         fc_fcp_complete_locked(fsp);
1123 unlock:
1124         fc_fcp_unlock_pkt(fsp);
1125 }
1126
1127 /*
1128  * Scsi abort handler- calls to send an abort
1129  * and then wait for abort completion
1130  */
1131 static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1132 {
1133         int rc = FAILED;
1134
1135         if (fc_fcp_send_abort(fsp))
1136                 return FAILED;
1137
1138         init_completion(&fsp->tm_done);
1139         fsp->wait_for_comp = 1;
1140
1141         spin_unlock_bh(&fsp->scsi_pkt_lock);
1142         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1143         spin_lock_bh(&fsp->scsi_pkt_lock);
1144         fsp->wait_for_comp = 0;
1145
1146         if (!rc) {
1147                 FC_DBG("target abort cmd  failed\n");
1148                 rc = FAILED;
1149         } else if (fsp->state & FC_SRB_ABORTED) {
1150                 FC_DBG("target abort cmd  passed\n");
1151                 rc = SUCCESS;
1152                 fc_fcp_complete_locked(fsp);
1153         }
1154
1155         return rc;
1156 }
1157
1158 /*
1159  * Retry LUN reset after resource allocation failed.
1160  */
1161 static void fc_lun_reset_send(unsigned long data)
1162 {
1163         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1164         struct fc_lport *lp = fsp->lp;
1165         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1166                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1167                         return;
1168                 if (fc_fcp_lock_pkt(fsp))
1169                         return;
1170                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1171                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1172                 fc_fcp_unlock_pkt(fsp);
1173         }
1174 }
1175
1176 /*
1177  * Scsi device reset handler- send a LUN RESET to the device
1178  * and wait for reset reply
1179  */
1180 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1181                         unsigned int id, unsigned int lun)
1182 {
1183         int rc;
1184
1185         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1186         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1187         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1188
1189         fsp->wait_for_comp = 1;
1190         init_completion(&fsp->tm_done);
1191
1192         fc_lun_reset_send((unsigned long)fsp);
1193
1194         /*
1195          * wait for completion of reset
1196          * after that make sure all commands are terminated
1197          */
1198         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1199
1200         spin_lock_bh(&fsp->scsi_pkt_lock);
1201         fsp->state |= FC_SRB_COMPL;
1202         spin_unlock_bh(&fsp->scsi_pkt_lock);
1203
1204         del_timer_sync(&fsp->timer);
1205
1206         spin_lock_bh(&fsp->scsi_pkt_lock);
1207         if (fsp->seq_ptr) {
1208                 lp->tt.exch_done(fsp->seq_ptr);
1209                 fsp->seq_ptr = NULL;
1210         }
1211         fsp->wait_for_comp = 0;
1212         spin_unlock_bh(&fsp->scsi_pkt_lock);
1213
1214         if (!rc) {
1215                 FC_DBG("lun reset failed\n");
1216                 return FAILED;
1217         }
1218
1219         /* cdb_status holds the tmf's rsp code */
1220         if (fsp->cdb_status != FCP_TMF_CMPL)
1221                 return FAILED;
1222
1223         FC_DBG("lun reset to lun %u completed\n", lun);
1224         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1225         return SUCCESS;
1226 }
1227
1228 /*
1229  * Task Managment response handler
1230  */
1231 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1232 {
1233         struct fc_fcp_pkt *fsp = arg;
1234         struct fc_frame_header *fh;
1235
1236         if (IS_ERR(fp)) {
1237                 /*
1238                  * If there is an error just let it timeout or wait
1239                  * for TMF to be aborted if it timedout.
1240                  *
1241                  * scsi-eh will escalate for when either happens.
1242                  */
1243                 return;
1244         }
1245
1246         if (fc_fcp_lock_pkt(fsp))
1247                 return;
1248
1249         /*
1250          * raced with eh timeout handler.
1251          */
1252         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1253                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1254                 return;
1255         }
1256
1257         fh = fc_frame_header_get(fp);
1258         if (fh->fh_type != FC_TYPE_BLS)
1259                 fc_fcp_resp(fsp, fp);
1260         fsp->seq_ptr = NULL;
1261         fsp->lp->tt.exch_done(seq);
1262         fc_frame_free(fp);
1263         fc_fcp_unlock_pkt(fsp);
1264 }
1265
1266 static void fc_fcp_cleanup(struct fc_lport *lp)
1267 {
1268         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1269 }
1270
1271 /*
1272  * fc_fcp_timeout: called by OS timer function.
1273  *
1274  * The timer has been inactivated and must be reactivated if desired
1275  * using fc_fcp_timer_set().
1276  *
1277  * Algorithm:
1278  *
1279  * If REC is supported, just issue it, and return.  The REC exchange will
1280  * complete or time out, and recovery can continue at that point.
1281  *
1282  * Otherwise, if the response has been received without all the data,
1283  * it has been ER_TIMEOUT since the response was received.
1284  *
1285  * If the response has not been received,
1286  * we see if data was received recently.  If it has been, we continue waiting,
1287  * otherwise, we abort the command.
1288  */
1289 static void fc_fcp_timeout(unsigned long data)
1290 {
1291         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1292         struct fc_rport *rport = fsp->rport;
1293         struct fc_rport_libfc_priv *rp = rport->dd_data;
1294
1295         if (fc_fcp_lock_pkt(fsp))
1296                 return;
1297
1298         if (fsp->cdb_cmd.fc_tm_flags)
1299                 goto unlock;
1300
1301         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1302
1303         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1304                 fc_fcp_rec(fsp);
1305         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1306                                jiffies))
1307                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1308         else if (fsp->state & FC_SRB_RCV_STATUS)
1309                 fc_fcp_complete_locked(fsp);
1310         else
1311                 fc_timeout_error(fsp);
1312         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1313 unlock:
1314         fc_fcp_unlock_pkt(fsp);
1315 }
1316
1317 /*
1318  * Send a REC ELS request
1319  */
1320 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1321 {
1322         struct fc_lport *lp;
1323         struct fc_frame *fp;
1324         struct fc_rport *rport;
1325         struct fc_rport_libfc_priv *rp;
1326
1327         lp = fsp->lp;
1328         rport = fsp->rport;
1329         rp = rport->dd_data;
1330         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1331                 fsp->status_code = FC_HRD_ERROR;
1332                 fsp->io_status = 0;
1333                 fc_fcp_complete_locked(fsp);
1334                 return;
1335         }
1336         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1337         if (!fp)
1338                 goto retry;
1339
1340         fr_seq(fp) = fsp->seq_ptr;
1341         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1342                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1343                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1344         if (lp->tt.elsct_send(lp, rport, fp, ELS_REC, fc_fcp_rec_resp,
1345                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1346                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1347                 return;
1348         }
1349         fc_frame_free(fp);
1350 retry:
1351         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1352                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1353         else
1354                 fc_timeout_error(fsp);
1355 }
1356
1357 /*
1358  * Receive handler for REC ELS frame
1359  * if it is a reject then let the scsi layer to handle
1360  * the timeout. if it is a LS_ACC then if the io was not completed
1361  * then set the timeout and return otherwise complete the exchange
1362  * and tell the scsi layer to restart the I/O.
1363  */
1364 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1365 {
1366         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1367         struct fc_els_rec_acc *recp;
1368         struct fc_els_ls_rjt *rjt;
1369         u32 e_stat;
1370         u8 opcode;
1371         u32 offset;
1372         enum dma_data_direction data_dir;
1373         enum fc_rctl r_ctl;
1374         struct fc_rport_libfc_priv *rp;
1375
1376         if (IS_ERR(fp)) {
1377                 fc_fcp_rec_error(fsp, fp);
1378                 return;
1379         }
1380
1381         if (fc_fcp_lock_pkt(fsp))
1382                 goto out;
1383
1384         fsp->recov_retry = 0;
1385         opcode = fc_frame_payload_op(fp);
1386         if (opcode == ELS_LS_RJT) {
1387                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1388                 switch (rjt->er_reason) {
1389                 default:
1390                         FC_DEBUG_FCP("device %x unexpected REC reject "
1391                                      "reason %d expl %d\n",
1392                                      fsp->rport->port_id, rjt->er_reason,
1393                                      rjt->er_explan);
1394                         /* fall through */
1395                 case ELS_RJT_UNSUP:
1396                         FC_DEBUG_FCP("device does not support REC\n");
1397                         rp = fsp->rport->dd_data;
1398                         /*
1399                          * if we do not spport RECs or got some bogus
1400                          * reason then resetup timer so we check for
1401                          * making progress.
1402                          */
1403                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1404                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1405                         break;
1406                 case ELS_RJT_LOGIC:
1407                 case ELS_RJT_UNAB:
1408                         /*
1409                          * If no data transfer, the command frame got dropped
1410                          * so we just retry.  If data was transferred, we
1411                          * lost the response but the target has no record,
1412                          * so we abort and retry.
1413                          */
1414                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1415                             fsp->xfer_len == 0) {
1416                                 fc_fcp_retry_cmd(fsp);
1417                                 break;
1418                         }
1419                         fc_timeout_error(fsp);
1420                         break;
1421                 }
1422         } else if (opcode == ELS_LS_ACC) {
1423                 if (fsp->state & FC_SRB_ABORTED)
1424                         goto unlock_out;
1425
1426                 data_dir = fsp->cmd->sc_data_direction;
1427                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1428                 offset = ntohl(recp->reca_fc4value);
1429                 e_stat = ntohl(recp->reca_e_stat);
1430
1431                 if (e_stat & ESB_ST_COMPLETE) {
1432
1433                         /*
1434                          * The exchange is complete.
1435                          *
1436                          * For output, we must've lost the response.
1437                          * For input, all data must've been sent.
1438                          * We lost may have lost the response
1439                          * (and a confirmation was requested) and maybe
1440                          * some data.
1441                          *
1442                          * If all data received, send SRR
1443                          * asking for response.  If partial data received,
1444                          * or gaps, SRR requests data at start of gap.
1445                          * Recovery via SRR relies on in-order-delivery.
1446                          */
1447                         if (data_dir == DMA_TO_DEVICE) {
1448                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1449                         } else if (fsp->xfer_contig_end == offset) {
1450                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1451                         } else {
1452                                 offset = fsp->xfer_contig_end;
1453                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1454                         }
1455                         fc_fcp_srr(fsp, r_ctl, offset);
1456                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1457
1458                         /*
1459                          * The remote port has the initiative, so just
1460                          * keep waiting for it to complete.
1461                          */
1462                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1463                 } else {
1464
1465                         /*
1466                          * The exchange is incomplete, we have seq. initiative.
1467                          * Lost response with requested confirmation,
1468                          * lost confirmation, lost transfer ready or
1469                          * lost write data.
1470                          *
1471                          * For output, if not all data was received, ask
1472                          * for transfer ready to be repeated.
1473                          *
1474                          * If we received or sent all the data, send SRR to
1475                          * request response.
1476                          *
1477                          * If we lost a response, we may have lost some read
1478                          * data as well.
1479                          */
1480                         r_ctl = FC_RCTL_DD_SOL_DATA;
1481                         if (data_dir == DMA_TO_DEVICE) {
1482                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1483                                 if (offset < fsp->data_len)
1484                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1485                         } else if (offset == fsp->xfer_contig_end) {
1486                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1487                         } else if (fsp->xfer_contig_end < offset) {
1488                                 offset = fsp->xfer_contig_end;
1489                         }
1490                         fc_fcp_srr(fsp, r_ctl, offset);
1491                 }
1492         }
1493 unlock_out:
1494         fc_fcp_unlock_pkt(fsp);
1495 out:
1496         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1497         fc_frame_free(fp);
1498 }
1499
1500 /*
1501  * Handle error response or timeout for REC exchange.
1502  */
1503 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1504 {
1505         int error = PTR_ERR(fp);
1506
1507         if (fc_fcp_lock_pkt(fsp))
1508                 goto out;
1509
1510         switch (error) {
1511         case -FC_EX_CLOSED:
1512                 fc_fcp_retry_cmd(fsp);
1513                 break;
1514
1515         default:
1516                 FC_DBG("REC %p fid %x error unexpected error %d\n",
1517                        fsp, fsp->rport->port_id, error);
1518                 fsp->status_code = FC_CMD_PLOGO;
1519                 /* fall through */
1520
1521         case -FC_EX_TIMEOUT:
1522                 /*
1523                  * Assume REC or LS_ACC was lost.
1524                  * The exchange manager will have aborted REC, so retry.
1525                  */
1526                 FC_DBG("REC fid %x error error %d retry %d/%d\n",
1527                        fsp->rport->port_id, error, fsp->recov_retry,
1528                        FC_MAX_RECOV_RETRY);
1529                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1530                         fc_fcp_rec(fsp);
1531                 else
1532                         fc_timeout_error(fsp);
1533                 break;
1534         }
1535         fc_fcp_unlock_pkt(fsp);
1536 out:
1537         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1538 }
1539
1540 /*
1541  * Time out error routine:
1542  * abort's the I/O close the exchange and
1543  * send completion notification to scsi layer
1544  */
1545 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1546 {
1547         fsp->status_code = FC_CMD_TIME_OUT;
1548         fsp->cdb_status = 0;
1549         fsp->io_status = 0;
1550         /*
1551          * if this fails then we let the scsi command timer fire and
1552          * scsi-ml escalate.
1553          */
1554         fc_fcp_send_abort(fsp);
1555 }
1556
1557 /*
1558  * Sequence retransmission request.
1559  * This is called after receiving status but insufficient data, or
1560  * when expecting status but the request has timed out.
1561  */
1562 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1563 {
1564         struct fc_lport *lp = fsp->lp;
1565         struct fc_rport *rport;
1566         struct fc_rport_libfc_priv *rp;
1567         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1568         struct fc_seq *seq;
1569         struct fcp_srr *srr;
1570         struct fc_frame *fp;
1571         u8 cdb_op;
1572
1573         rport = fsp->rport;
1574         rp = rport->dd_data;
1575         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1576
1577         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1578                 goto retry;                     /* shouldn't happen */
1579         fp = fc_frame_alloc(lp, sizeof(*srr));
1580         if (!fp)
1581                 goto retry;
1582
1583         srr = fc_frame_payload_get(fp, sizeof(*srr));
1584         memset(srr, 0, sizeof(*srr));
1585         srr->srr_op = ELS_SRR;
1586         srr->srr_ox_id = htons(ep->oxid);
1587         srr->srr_rx_id = htons(ep->rxid);
1588         srr->srr_r_ctl = r_ctl;
1589         srr->srr_rel_off = htonl(offset);
1590
1591         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1592                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1593                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1594
1595         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1596                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1597         if (!seq) {
1598                 fc_frame_free(fp);
1599                 goto retry;
1600         }
1601         fsp->recov_seq = seq;
1602         fsp->xfer_len = offset;
1603         fsp->xfer_contig_end = offset;
1604         fsp->state &= ~FC_SRB_RCV_STATUS;
1605         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1606         return;
1607 retry:
1608         fc_fcp_retry_cmd(fsp);
1609 }
1610
1611 /*
1612  * Handle response from SRR.
1613  */
1614 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1615 {
1616         struct fc_fcp_pkt *fsp = arg;
1617         struct fc_frame_header *fh;
1618
1619         if (IS_ERR(fp)) {
1620                 fc_fcp_srr_error(fsp, fp);
1621                 return;
1622         }
1623
1624         if (fc_fcp_lock_pkt(fsp))
1625                 goto out;
1626
1627         fh = fc_frame_header_get(fp);
1628         /*
1629          * BUG? fc_fcp_srr_error calls exch_done which would release
1630          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1631          * then fc_exch_timeout would be sending an abort. The exch_done
1632          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1633          * an abort response though.
1634          */
1635         if (fh->fh_type == FC_TYPE_BLS) {
1636                 fc_fcp_unlock_pkt(fsp);
1637                 return;
1638         }
1639
1640         fsp->recov_seq = NULL;
1641         switch (fc_frame_payload_op(fp)) {
1642         case ELS_LS_ACC:
1643                 fsp->recov_retry = 0;
1644                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1645                 break;
1646         case ELS_LS_RJT:
1647         default:
1648                 fc_timeout_error(fsp);
1649                 break;
1650         }
1651         fc_fcp_unlock_pkt(fsp);
1652         fsp->lp->tt.exch_done(seq);
1653 out:
1654         fc_frame_free(fp);
1655         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1656 }
1657
1658 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1659 {
1660         if (fc_fcp_lock_pkt(fsp))
1661                 goto out;
1662         fsp->lp->tt.exch_done(fsp->recov_seq);
1663         fsp->recov_seq = NULL;
1664         switch (PTR_ERR(fp)) {
1665         case -FC_EX_TIMEOUT:
1666                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1667                         fc_fcp_rec(fsp);
1668                 else
1669                         fc_timeout_error(fsp);
1670                 break;
1671         case -FC_EX_CLOSED:                     /* e.g., link failure */
1672                 /* fall through */
1673         default:
1674                 fc_fcp_retry_cmd(fsp);
1675                 break;
1676         }
1677         fc_fcp_unlock_pkt(fsp);
1678 out:
1679         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1680 }
1681
1682 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1683 {
1684         /* lock ? */
1685         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1686 }
1687
1688 /**
1689  * fc_queuecommand - The queuecommand function of the scsi template
1690  * @cmd:        struct scsi_cmnd to be executed
1691  * @done:       Callback function to be called when cmd is completed
1692  *
1693  * this is the i/o strategy routine, called by the scsi layer
1694  * this routine is called with holding the host_lock.
1695  */
1696 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1697 {
1698         struct fc_lport *lp;
1699         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1700         struct fc_fcp_pkt *fsp;
1701         struct fc_rport_libfc_priv *rp;
1702         int rval;
1703         int rc = 0;
1704         struct fcoe_dev_stats *stats;
1705
1706         lp = shost_priv(sc_cmd->device->host);
1707
1708         rval = fc_remote_port_chkready(rport);
1709         if (rval) {
1710                 sc_cmd->result = rval;
1711                 done(sc_cmd);
1712                 goto out;
1713         }
1714
1715         if (!*(struct fc_remote_port **)rport->dd_data) {
1716                 /*
1717                  * rport is transitioning from blocked/deleted to
1718                  * online
1719                  */
1720                 sc_cmd->result = DID_IMM_RETRY << 16;
1721                 done(sc_cmd);
1722                 goto out;
1723         }
1724
1725         rp = rport->dd_data;
1726
1727         if (!fc_fcp_lport_queue_ready(lp)) {
1728                 rc = SCSI_MLQUEUE_HOST_BUSY;
1729                 goto out;
1730         }
1731
1732         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1733         if (fsp == NULL) {
1734                 rc = SCSI_MLQUEUE_HOST_BUSY;
1735                 goto out;
1736         }
1737
1738         /*
1739          * build the libfc request pkt
1740          */
1741         fsp->cmd = sc_cmd;      /* save the cmd */
1742         fsp->lp = lp;           /* save the softc ptr */
1743         fsp->rport = rport;     /* set the remote port ptr */
1744         sc_cmd->scsi_done = done;
1745
1746         /*
1747          * set up the transfer length
1748          */
1749         fsp->data_len = scsi_bufflen(sc_cmd);
1750         fsp->xfer_len = 0;
1751
1752         /*
1753          * setup the data direction
1754          */
1755         stats = lp->dev_stats[smp_processor_id()];
1756         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1757                 fsp->req_flags = FC_SRB_READ;
1758                 stats->InputRequests++;
1759                 stats->InputMegabytes = fsp->data_len;
1760         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1761                 fsp->req_flags = FC_SRB_WRITE;
1762                 stats->OutputRequests++;
1763                 stats->OutputMegabytes = fsp->data_len;
1764         } else {
1765                 fsp->req_flags = 0;
1766                 stats->ControlRequests++;
1767         }
1768
1769         fsp->tgt_flags = rp->flags;
1770
1771         init_timer(&fsp->timer);
1772         fsp->timer.data = (unsigned long)fsp;
1773
1774         /*
1775          * send it to the lower layer
1776          * if we get -1 return then put the request in the pending
1777          * queue.
1778          */
1779         rval = fc_fcp_pkt_send(lp, fsp);
1780         if (rval != 0) {
1781                 fsp->state = FC_SRB_FREE;
1782                 fc_fcp_pkt_release(fsp);
1783                 rc = SCSI_MLQUEUE_HOST_BUSY;
1784         }
1785 out:
1786         return rc;
1787 }
1788 EXPORT_SYMBOL(fc_queuecommand);
1789
1790 /**
1791  * fc_io_compl() -  Handle responses for completed commands
1792  * @fsp:        scsi packet
1793  *
1794  * Translates a error to a Linux SCSI error.
1795  *
1796  * The fcp packet lock must be held when calling.
1797  */
1798 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1799 {
1800         struct fc_fcp_internal *si;
1801         struct scsi_cmnd *sc_cmd;
1802         struct fc_lport *lp;
1803         unsigned long flags;
1804
1805         /* release outstanding ddp context */
1806         fc_fcp_ddp_done(fsp);
1807
1808         fsp->state |= FC_SRB_COMPL;
1809         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1810                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1811                 del_timer_sync(&fsp->timer);
1812                 spin_lock_bh(&fsp->scsi_pkt_lock);
1813         }
1814
1815         lp = fsp->lp;
1816         si = fc_get_scsi_internal(lp);
1817         spin_lock_irqsave(lp->host->host_lock, flags);
1818         if (!fsp->cmd) {
1819                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1820                 return;
1821         }
1822
1823         /*
1824          * if a command timed out while we had to try and throttle IO
1825          * and it is now getting cleaned up, then we are about to
1826          * try again so clear the throttled flag incase we get more
1827          * time outs.
1828          */
1829         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1830                 si->throttled = 0;
1831
1832         sc_cmd = fsp->cmd;
1833         fsp->cmd = NULL;
1834
1835         if (!sc_cmd->SCp.ptr) {
1836                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1837                 return;
1838         }
1839
1840         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1841         switch (fsp->status_code) {
1842         case FC_COMPLETE:
1843                 if (fsp->cdb_status == 0) {
1844                         /*
1845                          * good I/O status
1846                          */
1847                         sc_cmd->result = DID_OK << 16;
1848                         if (fsp->scsi_resid)
1849                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1850                 } else if (fsp->cdb_status == QUEUE_FULL) {
1851                         struct scsi_device *tmp_sdev;
1852                         struct scsi_device *sdev = sc_cmd->device;
1853
1854                         shost_for_each_device(tmp_sdev, sdev->host) {
1855                                 if (tmp_sdev->id != sdev->id)
1856                                         continue;
1857
1858                                 if (tmp_sdev->queue_depth > 1) {
1859                                         scsi_track_queue_full(tmp_sdev,
1860                                                               tmp_sdev->
1861                                                               queue_depth - 1);
1862                                 }
1863                         }
1864                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1865                 } else {
1866                         /*
1867                          * transport level I/O was ok but scsi
1868                          * has non zero status
1869                          */
1870                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1871                 }
1872                 break;
1873         case FC_ERROR:
1874                 sc_cmd->result = DID_ERROR << 16;
1875                 break;
1876         case FC_DATA_UNDRUN:
1877                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1878                         /*
1879                          * scsi status is good but transport level
1880                          * underrun.
1881                          */
1882                         sc_cmd->result = DID_OK << 16;
1883                 } else {
1884                         /*
1885                          * scsi got underrun, this is an error
1886                          */
1887                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1888                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1889                 }
1890                 break;
1891         case FC_DATA_OVRRUN:
1892                 /*
1893                  * overrun is an error
1894                  */
1895                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1896                 break;
1897         case FC_CMD_ABORTED:
1898                 sc_cmd->result = (DID_ABORT << 16) | fsp->io_status;
1899                 break;
1900         case FC_CMD_TIME_OUT:
1901                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1902                 break;
1903         case FC_CMD_RESET:
1904                 sc_cmd->result = (DID_RESET << 16);
1905                 break;
1906         case FC_HRD_ERROR:
1907                 sc_cmd->result = (DID_NO_CONNECT << 16);
1908                 break;
1909         default:
1910                 sc_cmd->result = (DID_ERROR << 16);
1911                 break;
1912         }
1913
1914         list_del(&fsp->list);
1915         sc_cmd->SCp.ptr = NULL;
1916         sc_cmd->scsi_done(sc_cmd);
1917         spin_unlock_irqrestore(lp->host->host_lock, flags);
1918
1919         /* release ref from initial allocation in queue command */
1920         fc_fcp_pkt_release(fsp);
1921 }
1922
1923 /**
1924  * fc_fcp_complete() - complete processing of a fcp packet
1925  * @fsp:        fcp packet
1926  *
1927  * This function may sleep if a fsp timer is pending.
1928  * The host lock must not be held by caller.
1929  */
1930 void fc_fcp_complete(struct fc_fcp_pkt *fsp)
1931 {
1932         if (fc_fcp_lock_pkt(fsp))
1933                 return;
1934
1935         fc_fcp_complete_locked(fsp);
1936         fc_fcp_unlock_pkt(fsp);
1937 }
1938 EXPORT_SYMBOL(fc_fcp_complete);
1939
1940 /**
1941  * fc_eh_abort() - Abort a command
1942  * @sc_cmd:     scsi command to abort
1943  *
1944  * From scsi host template.
1945  * send ABTS to the target device  and wait for the response
1946  * sc_cmd is the pointer to the command to be aborted.
1947  */
1948 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1949 {
1950         struct fc_fcp_pkt *fsp;
1951         struct fc_lport *lp;
1952         int rc = FAILED;
1953         unsigned long flags;
1954
1955         lp = shost_priv(sc_cmd->device->host);
1956         if (lp->state != LPORT_ST_READY)
1957                 return rc;
1958         else if (!lp->link_up)
1959                 return rc;
1960
1961         spin_lock_irqsave(lp->host->host_lock, flags);
1962         fsp = CMD_SP(sc_cmd);
1963         if (!fsp) {
1964                 /* command completed while scsi eh was setting up */
1965                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1966                 return SUCCESS;
1967         }
1968         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1969         fc_fcp_pkt_hold(fsp);
1970         spin_unlock_irqrestore(lp->host->host_lock, flags);
1971
1972         if (fc_fcp_lock_pkt(fsp)) {
1973                 /* completed while we were waiting for timer to be deleted */
1974                 rc = SUCCESS;
1975                 goto release_pkt;
1976         }
1977
1978         rc = fc_fcp_pkt_abort(lp, fsp);
1979         fc_fcp_unlock_pkt(fsp);
1980
1981 release_pkt:
1982         fc_fcp_pkt_release(fsp);
1983         return rc;
1984 }
1985 EXPORT_SYMBOL(fc_eh_abort);
1986
1987 /**
1988  * fc_eh_device_reset() Reset a single LUN
1989  * @sc_cmd:     scsi command
1990  *
1991  * Set from scsi host template to send tm cmd to the target and wait for the
1992  * response.
1993  */
1994 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1995 {
1996         struct fc_lport *lp;
1997         struct fc_fcp_pkt *fsp;
1998         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1999         int rc = FAILED;
2000         struct fc_rport_libfc_priv *rp;
2001         int rval;
2002
2003         rval = fc_remote_port_chkready(rport);
2004         if (rval)
2005                 goto out;
2006
2007         rp = rport->dd_data;
2008         lp = shost_priv(sc_cmd->device->host);
2009
2010         if (lp->state != LPORT_ST_READY)
2011                 return rc;
2012
2013         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
2014         if (fsp == NULL) {
2015                 FC_DBG("could not allocate scsi_pkt\n");
2016                 sc_cmd->result = DID_NO_CONNECT << 16;
2017                 goto out;
2018         }
2019
2020         /*
2021          * Build the libfc request pkt. Do not set the scsi cmnd, because
2022          * the sc passed in is not setup for execution like when sent
2023          * through the queuecommand callout.
2024          */
2025         fsp->lp = lp;           /* save the softc ptr */
2026         fsp->rport = rport;     /* set the remote port ptr */
2027
2028         /*
2029          * flush outstanding commands
2030          */
2031         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2032         fsp->state = FC_SRB_FREE;
2033         fc_fcp_pkt_release(fsp);
2034
2035 out:
2036         return rc;
2037 }
2038 EXPORT_SYMBOL(fc_eh_device_reset);
2039
2040 /**
2041  * fc_eh_host_reset() - The reset function will reset the ports on the host.
2042  * @sc_cmd:     scsi command
2043  */
2044 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2045 {
2046         struct Scsi_Host *shost = sc_cmd->device->host;
2047         struct fc_lport *lp = shost_priv(shost);
2048         unsigned long wait_tmo;
2049
2050         lp->tt.lport_reset(lp);
2051         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2052         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
2053                 msleep(1000);
2054
2055         if (fc_fcp_lport_queue_ready(lp)) {
2056                 shost_printk(KERN_INFO, shost, "Host reset succeeded.\n");
2057                 return SUCCESS;
2058         } else {
2059                 shost_printk(KERN_INFO, shost, "Host reset failed. "
2060                              "lport not ready.\n");
2061                 return FAILED;
2062         }
2063 }
2064 EXPORT_SYMBOL(fc_eh_host_reset);
2065
2066 /**
2067  * fc_slave_alloc() - configure queue depth
2068  * @sdev:       scsi device
2069  *
2070  * Configures queue depth based on host's cmd_per_len. If not set
2071  * then we use the libfc default.
2072  */
2073 int fc_slave_alloc(struct scsi_device *sdev)
2074 {
2075         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2076         int queue_depth;
2077
2078         if (!rport || fc_remote_port_chkready(rport))
2079                 return -ENXIO;
2080
2081         if (sdev->tagged_supported) {
2082                 if (sdev->host->hostt->cmd_per_lun)
2083                         queue_depth = sdev->host->hostt->cmd_per_lun;
2084                 else
2085                         queue_depth = FC_FCP_DFLT_QUEUE_DEPTH;
2086                 scsi_activate_tcq(sdev, queue_depth);
2087         }
2088         return 0;
2089 }
2090 EXPORT_SYMBOL(fc_slave_alloc);
2091
2092 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
2093 {
2094         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2095         return sdev->queue_depth;
2096 }
2097 EXPORT_SYMBOL(fc_change_queue_depth);
2098
2099 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2100 {
2101         if (sdev->tagged_supported) {
2102                 scsi_set_tag_type(sdev, tag_type);
2103                 if (tag_type)
2104                         scsi_activate_tcq(sdev, sdev->queue_depth);
2105                 else
2106                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2107         } else
2108                 tag_type = 0;
2109
2110         return tag_type;
2111 }
2112 EXPORT_SYMBOL(fc_change_queue_type);
2113
2114 void fc_fcp_destroy(struct fc_lport *lp)
2115 {
2116         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2117
2118         if (!list_empty(&si->scsi_pkt_queue))
2119                 printk(KERN_ERR "Leaked scsi packets.\n");
2120
2121         mempool_destroy(si->scsi_pkt_pool);
2122         kfree(si);
2123         lp->scsi_priv = NULL;
2124 }
2125 EXPORT_SYMBOL(fc_fcp_destroy);
2126
2127 int fc_fcp_init(struct fc_lport *lp)
2128 {
2129         int rc;
2130         struct fc_fcp_internal *si;
2131
2132         if (!lp->tt.fcp_cmd_send)
2133                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2134
2135         if (!lp->tt.fcp_cleanup)
2136                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2137
2138         if (!lp->tt.fcp_abort_io)
2139                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2140
2141         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2142         if (!si)
2143                 return -ENOMEM;
2144         lp->scsi_priv = si;
2145         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2146
2147         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2148         if (!si->scsi_pkt_pool) {
2149                 rc = -ENOMEM;
2150                 goto free_internal;
2151         }
2152         return 0;
2153
2154 free_internal:
2155         kfree(si);
2156         return rc;
2157 }
2158 EXPORT_SYMBOL(fc_fcp_init);
2159
2160 static int __init libfc_init(void)
2161 {
2162         int rc;
2163
2164         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2165                                             sizeof(struct fc_fcp_pkt),
2166                                             0, SLAB_HWCACHE_ALIGN, NULL);
2167         if (scsi_pkt_cachep == NULL) {
2168                 FC_DBG("Unable to allocate SRB cache...module load failed!");
2169                 return -ENOMEM;
2170         }
2171
2172         rc = fc_setup_exch_mgr();
2173         if (rc)
2174                 goto destroy_pkt_cache;
2175
2176         rc = fc_setup_rport();
2177         if (rc)
2178                 goto destroy_em;
2179
2180         return rc;
2181 destroy_em:
2182         fc_destroy_exch_mgr();
2183 destroy_pkt_cache:
2184         kmem_cache_destroy(scsi_pkt_cachep);
2185         return rc;
2186 }
2187
2188 static void __exit libfc_exit(void)
2189 {
2190         kmem_cache_destroy(scsi_pkt_cachep);
2191         fc_destroy_exch_mgr();
2192         fc_destroy_rport();
2193 }
2194
2195 module_init(libfc_init);
2196 module_exit(libfc_exit);