drivers/scsi/libfc/fc_fcp.c

   1 /*
   2  * Copyright(c) 2007 Intel Corporation. All rights reserved.
   3  * Copyright(c) 2008 Red Hat, Inc.  All rights reserved.
   4  * Copyright(c) 2008 Mike Christie
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Maintained at www.Open-FCoE.org
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/delay.h>
  24 #include <linux/kernel.h>
  25 #include <linux/types.h>
  26 #include <linux/spinlock.h>
  27 #include <linux/scatterlist.h>
  28 #include <linux/err.h>
  29 #include <linux/crc32.h>
  30
  31 #include <scsi/scsi_tcq.h>
  32 #include <scsi/scsi.h>
  33 #include <scsi/scsi_host.h>
  34 #include <scsi/scsi_device.h>
  35 #include <scsi/scsi_cmnd.h>
  36
  37 #include <scsi/fc/fc_fc2.h>
  38
  39 #include <scsi/libfc.h>
  40 #include <scsi/fc_encode.h>
  41
  42 MODULE_AUTHOR("Open-FCoE.org");
  43 MODULE_DESCRIPTION("libfc");
  44 MODULE_LICENSE("GPL v2");
  45
  46 unsigned int fc_debug_logging;
  47 module_param_named(debug_logging, fc_debug_logging, int, S_IRUGO|S_IWUSR);
  48 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
  49
  50 static struct kmem_cache *scsi_pkt_cachep;
  51
  52 /* SRB state definitions */
  53 #define FC_SRB_FREE             0               /* cmd is free */
  54 #define FC_SRB_CMD_SENT         (1 << 0)        /* cmd has been sent */
  55 #define FC_SRB_RCV_STATUS       (1 << 1)        /* response has arrived */
  56 #define FC_SRB_ABORT_PENDING    (1 << 2)        /* cmd abort sent to device */
  57 #define FC_SRB_ABORTED          (1 << 3)        /* abort acknowleged */
  58 #define FC_SRB_DISCONTIG        (1 << 4)        /* non-sequential data recvd */
  59 #define FC_SRB_COMPL            (1 << 5)        /* fc_io_compl has been run */
  60 #define FC_SRB_FCP_PROCESSING_TMO (1 << 6)      /* timer function processing */
  61 #define FC_SRB_NOMEM            (1 << 7)        /* dropped to out of mem */
  62
  63 #define FC_SRB_READ             (1 << 1)
  64 #define FC_SRB_WRITE            (1 << 0)
  65
  66 /*
  67  * The SCp.ptr should be tested and set under the host lock. NULL indicates
  68  * that the command has been retruned to the scsi layer.
  69  */
  70 #define CMD_SP(Cmnd)                ((struct fc_fcp_pkt *)(Cmnd)->SCp.ptr)
  71 #define CMD_ENTRY_STATUS(Cmnd)      ((Cmnd)->SCp.have_data_in)
  72 #define CMD_COMPL_STATUS(Cmnd)      ((Cmnd)->SCp.this_residual)
  73 #define CMD_SCSI_STATUS(Cmnd)       ((Cmnd)->SCp.Status)
  74 #define CMD_RESID_LEN(Cmnd)         ((Cmnd)->SCp.buffers_residual)
  75
  76 struct fc_fcp_internal {
  77         mempool_t       *scsi_pkt_pool;
  78         struct list_head scsi_pkt_queue;
  79         u8              throttled;
  80 };
  81
  82 #define fc_get_scsi_internal(x) ((struct fc_fcp_internal *)(x)->scsi_priv)
  83
  84 /*
  85  * function prototypes
  86  * FC scsi I/O related functions
  87  */
  88 static void fc_fcp_recv_data(struct fc_fcp_pkt *, struct fc_frame *);
  89 static void fc_fcp_recv(struct fc_seq *, struct fc_frame *, void *);
  90 static void fc_fcp_resp(struct fc_fcp_pkt *, struct fc_frame *);
  91 static void fc_fcp_complete_locked(struct fc_fcp_pkt *);
  92 static void fc_tm_done(struct fc_seq *, struct fc_frame *, void *);
  93 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp);
  94 static void fc_timeout_error(struct fc_fcp_pkt *);
  95 static void fc_fcp_timeout(unsigned long data);
  96 static void fc_fcp_rec(struct fc_fcp_pkt *);
  97 static void fc_fcp_rec_error(struct fc_fcp_pkt *, struct fc_frame *);
  98 static void fc_fcp_rec_resp(struct fc_seq *, struct fc_frame *, void *);
  99 static void fc_io_compl(struct fc_fcp_pkt *);
 100
 101 static void fc_fcp_srr(struct fc_fcp_pkt *, enum fc_rctl, u32);
 102 static void fc_fcp_srr_resp(struct fc_seq *, struct fc_frame *, void *);
 103 static void fc_fcp_srr_error(struct fc_fcp_pkt *, struct fc_frame *);
 104
 105 /*
 106  * command status codes
 107  */
 108 #define FC_COMPLETE             0
 109 #define FC_CMD_ABORTED          1
 110 #define FC_CMD_RESET            2
 111 #define FC_CMD_PLOGO            3
 112 #define FC_SNS_RCV              4
 113 #define FC_TRANS_ERR            5
 114 #define FC_DATA_OVRRUN          6
 115 #define FC_DATA_UNDRUN          7
 116 #define FC_ERROR                8
 117 #define FC_HRD_ERROR            9
 118 #define FC_CMD_TIME_OUT         10
 119
 120 /*
 121  * Error recovery timeout values.
 122  */
 123 #define FC_SCSI_ER_TIMEOUT      (10 * HZ)
 124 #define FC_SCSI_TM_TOV          (10 * HZ)
 125 #define FC_SCSI_REC_TOV         (2 * HZ)
 126 #define FC_HOST_RESET_TIMEOUT   (30 * HZ)
 127
 128 #define FC_MAX_ERROR_CNT        5
 129 #define FC_MAX_RECOV_RETRY      3
 130
 131 #define FC_FCP_DFLT_QUEUE_DEPTH 32
 132
 133 /**
 134  * fc_fcp_pkt_alloc - allocation routine for scsi_pkt packet
 135  * @lp:         fc lport struct
 136  * @gfp:        gfp flags for allocation
 137  *
 138  * This is used by upper layer scsi driver.
 139  * Return Value : scsi_pkt structure or null on allocation failure.
 140  * Context      : call from process context. no locking required.
 141  */
 142 static struct fc_fcp_pkt *fc_fcp_pkt_alloc(struct fc_lport *lp, gfp_t gfp)
 143 {
 144         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 145         struct fc_fcp_pkt *fsp;
 146
 147         fsp = mempool_alloc(si->scsi_pkt_pool, gfp);
 148         if (fsp) {
 149                 memset(fsp, 0, sizeof(*fsp));
 150                 fsp->lp = lp;
 151                 atomic_set(&fsp->ref_cnt, 1);
 152                 init_timer(&fsp->timer);
 153                 INIT_LIST_HEAD(&fsp->list);
 154                 spin_lock_init(&fsp->scsi_pkt_lock);
 155         }
 156         return fsp;
 157 }
 158
 159 /**
 160  * fc_fcp_pkt_release() - release hold on scsi_pkt packet
 161  * @fsp:        fcp packet struct
 162  *
 163  * This is used by upper layer scsi driver.
 164  * Context      : call from process  and interrupt context.
 165  *                no locking required
 166  */
 167 static void fc_fcp_pkt_release(struct fc_fcp_pkt *fsp)
 168 {
 169         if (atomic_dec_and_test(&fsp->ref_cnt)) {
 170                 struct fc_fcp_internal *si = fc_get_scsi_internal(fsp->lp);
 171
 172                 mempool_free(fsp, si->scsi_pkt_pool);
 173         }
 174 }
 175
 176 static void fc_fcp_pkt_hold(struct fc_fcp_pkt *fsp)
 177 {
 178         atomic_inc(&fsp->ref_cnt);
 179 }
 180
 181 /**
 182  * fc_fcp_pkt_destory() - release hold on scsi_pkt packet
 183  * @seq:                exchange sequence
 184  * @fsp:        fcp packet struct
 185  *
 186  * Release hold on scsi_pkt packet set to keep scsi_pkt
 187  * till EM layer exch resource is not freed.
 188  * Context      : called from from EM layer.
 189  *                no locking required
 190  */
 191 static void fc_fcp_pkt_destroy(struct fc_seq *seq, void *fsp)
 192 {
 193         fc_fcp_pkt_release(fsp);
 194 }
 195
 196 /**
 197  * fc_fcp_lock_pkt() - lock a packet and get a ref to it.
 198  * @fsp:        fcp packet
 199  *
 200  * We should only return error if we return a command to scsi-ml before
 201  * getting a response. This can happen in cases where we send a abort, but
 202  * do not wait for the response and the abort and command can be passing
 203  * each other on the wire/network-layer.
 204  *
 205  * Note: this function locks the packet and gets a reference to allow
 206  * callers to call the completion function while the lock is held and
 207  * not have to worry about the packets refcount.
 208  *
 209  * TODO: Maybe we should just have callers grab/release the lock and
 210  * have a function that they call to verify the fsp and grab a ref if
 211  * needed.
 212  */
 213 static inline int fc_fcp_lock_pkt(struct fc_fcp_pkt *fsp)
 214 {
 215         spin_lock_bh(&fsp->scsi_pkt_lock);
 216         if (fsp->state & FC_SRB_COMPL) {
 217                 spin_unlock_bh(&fsp->scsi_pkt_lock);
 218                 return -EPERM;
 219         }
 220
 221         fc_fcp_pkt_hold(fsp);
 222         return 0;
 223 }
 224
 225 static inline void fc_fcp_unlock_pkt(struct fc_fcp_pkt *fsp)
 226 {
 227         spin_unlock_bh(&fsp->scsi_pkt_lock);
 228         fc_fcp_pkt_release(fsp);
 229 }
 230
 231 static void fc_fcp_timer_set(struct fc_fcp_pkt *fsp, unsigned long delay)
 232 {
 233         if (!(fsp->state & FC_SRB_COMPL))
 234                 mod_timer(&fsp->timer, jiffies + delay);
 235 }
 236
 237 static int fc_fcp_send_abort(struct fc_fcp_pkt *fsp)
 238 {
 239         if (!fsp->seq_ptr)
 240                 return -EINVAL;
 241
 242         fsp->state |= FC_SRB_ABORT_PENDING;
 243         return fsp->lp->tt.seq_exch_abort(fsp->seq_ptr, 0);
 244 }
 245
 246 /*
 247  * Retry command.
 248  * An abort isn't needed.
 249  */
 250 static void fc_fcp_retry_cmd(struct fc_fcp_pkt *fsp)
 251 {
 252         if (fsp->seq_ptr) {
 253                 fsp->lp->tt.exch_done(fsp->seq_ptr);
 254                 fsp->seq_ptr = NULL;
 255         }
 256
 257         fsp->state &= ~FC_SRB_ABORT_PENDING;
 258         fsp->io_status = 0;
 259         fsp->status_code = FC_ERROR;
 260         fc_fcp_complete_locked(fsp);
 261 }
 262
 263 /*
 264  * fc_fcp_ddp_setup - calls to LLD's ddp_setup to set up DDP
 265  * transfer for a read I/O indicated by the fc_fcp_pkt.
 266  * @fsp: ptr to the fc_fcp_pkt
 267  *
 268  * This is called in exch_seq_send() when we have a newly allocated
 269  * exchange with a valid exchange id to setup ddp.
 270  *
 271  * returns: none
 272  */
 273 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid)
 274 {
 275         struct fc_lport *lp;
 276
 277         if (!fsp)
 278                 return;
 279
 280         lp = fsp->lp;
 281         if ((fsp->req_flags & FC_SRB_READ) &&
 282             (lp->lro_enabled) && (lp->tt.ddp_setup)) {
 283                 if (lp->tt.ddp_setup(lp, xid, scsi_sglist(fsp->cmd),
 284                                      scsi_sg_count(fsp->cmd)))
 285                         fsp->xfer_ddp = xid;
 286         }
 287 }
 288 EXPORT_SYMBOL(fc_fcp_ddp_setup);
 289
 290 /*
 291  * fc_fcp_ddp_done - calls to LLD's ddp_done to release any
 292  * DDP related resources for this I/O if it is initialized
 293  * as a ddp transfer
 294  * @fsp: ptr to the fc_fcp_pkt
 295  *
 296  * returns: none
 297  */
 298 static void fc_fcp_ddp_done(struct fc_fcp_pkt *fsp)
 299 {
 300         struct fc_lport *lp;
 301
 302         if (!fsp)
 303                 return;
 304
 305         lp = fsp->lp;
 306         if (fsp->xfer_ddp && lp->tt.ddp_done) {
 307                 fsp->xfer_len = lp->tt.ddp_done(lp, fsp->xfer_ddp);
 308                 fsp->xfer_ddp = 0;
 309         }
 310 }
 311
 312
 313 /*
 314  * Receive SCSI data from target.
 315  * Called after receiving solicited data.
 316  */
 317 static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 318 {
 319         struct scsi_cmnd *sc = fsp->cmd;
 320         struct fc_lport *lp = fsp->lp;
 321         struct fcoe_dev_stats *stats;
 322         struct fc_frame_header *fh;
 323         size_t start_offset;
 324         size_t offset;
 325         u32 crc;
 326         u32 copy_len = 0;
 327         size_t len;
 328         void *buf;
 329         struct scatterlist *sg;
 330         size_t remaining;
 331
 332         fh = fc_frame_header_get(fp);
 333         offset = ntohl(fh->fh_parm_offset);
 334         start_offset = offset;
 335         len = fr_len(fp) - sizeof(*fh);
 336         buf = fc_frame_payload_get(fp, 0);
 337
 338         /* if this I/O is ddped, update xfer len */
 339         fc_fcp_ddp_done(fsp);
 340
 341         if (offset + len > fsp->data_len) {
 342                 /* this should never happen */
 343                 if ((fr_flags(fp) & FCPHF_CRC_UNCHECKED) &&
 344                     fc_frame_crc_check(fp))
 345                         goto crc_err;
 346                 FC_FCP_DBG(fsp, "data received past end. len %zx offset %zx "
 347                            "data_len %x\n", len, offset, fsp->data_len);
 348                 fc_fcp_retry_cmd(fsp);
 349                 return;
 350         }
 351         if (offset != fsp->xfer_len)
 352                 fsp->state |= FC_SRB_DISCONTIG;
 353
 354         crc = 0;
 355         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 356                 crc = crc32(~0, (u8 *) fh, sizeof(*fh));
 357
 358         sg = scsi_sglist(sc);
 359         remaining = len;
 360
 361         while (remaining > 0 && sg) {
 362                 size_t off;
 363                 void *page_addr;
 364                 size_t sg_bytes;
 365
 366                 if (offset >= sg->length) {
 367                         offset -= sg->length;
 368                         sg = sg_next(sg);
 369                         continue;
 370                 }
 371                 sg_bytes = min(remaining, sg->length - offset);
 372
 373                 /*
 374                  * The scatterlist item may be bigger than PAGE_SIZE,
 375                  * but we are limited to mapping PAGE_SIZE at a time.
 376                  */
 377                 off = offset + sg->offset;
 378                 sg_bytes = min(sg_bytes, (size_t)
 379                                (PAGE_SIZE - (off & ~PAGE_MASK)));
 380                 page_addr = kmap_atomic(sg_page(sg) + (off >> PAGE_SHIFT),
 381                                         KM_SOFTIRQ0);
 382                 if (!page_addr)
 383                         break;          /* XXX panic? */
 384
 385                 if (fr_flags(fp) & FCPHF_CRC_UNCHECKED)
 386                         crc = crc32(crc, buf, sg_bytes);
 387                 memcpy((char *)page_addr + (off & ~PAGE_MASK), buf,
 388                        sg_bytes);
 389
 390                 kunmap_atomic(page_addr, KM_SOFTIRQ0);
 391                 buf += sg_bytes;
 392                 offset += sg_bytes;
 393                 remaining -= sg_bytes;
 394                 copy_len += sg_bytes;
 395         }
 396
 397         if (fr_flags(fp) & FCPHF_CRC_UNCHECKED) {
 398                 buf = fc_frame_payload_get(fp, 0);
 399                 if (len % 4) {
 400                         crc = crc32(crc, buf + len, 4 - (len % 4));
 401                         len += 4 - (len % 4);
 402                 }
 403
 404                 if (~crc != le32_to_cpu(fr_crc(fp))) {
 405 crc_err:
 406                         stats = fc_lport_get_stats(lp);
 407                         stats->ErrorFrames++;
 408                         /* FIXME - per cpu count, not total count! */
 409                         if (stats->InvalidCRCCount++ < 5)
 410                                 printk(KERN_WARNING "libfc: CRC error on data "
 411                                        "frame for port (%6x)\n",
 412                                        fc_host_port_id(lp->host));
 413                         /*
 414                          * Assume the frame is total garbage.
 415                          * We may have copied it over the good part
 416                          * of the buffer.
 417                          * If so, we need to retry the entire operation.
 418                          * Otherwise, ignore it.
 419                          */
 420                         if (fsp->state & FC_SRB_DISCONTIG)
 421                                 fc_fcp_retry_cmd(fsp);
 422                         return;
 423                 }
 424         }
 425
 426         if (fsp->xfer_contig_end == start_offset)
 427                 fsp->xfer_contig_end += copy_len;
 428         fsp->xfer_len += copy_len;
 429
 430         /*
 431          * In the very rare event that this data arrived after the response
 432          * and completes the transfer, call the completion handler.
 433          */
 434         if (unlikely(fsp->state & FC_SRB_RCV_STATUS) &&
 435             fsp->xfer_len == fsp->data_len - fsp->scsi_resid)
 436                 fc_fcp_complete_locked(fsp);
 437 }
 438
 439 /**
 440  * fc_fcp_send_data() -  Send SCSI data to target.
 441  * @fsp: ptr to fc_fcp_pkt
 442  * @sp: ptr to this sequence
 443  * @offset: starting offset for this data request
 444  * @seq_blen: the burst length for this data request
 445  *
 446  * Called after receiving a Transfer Ready data descriptor.
 447  * if LLD is capable of seq offload then send down seq_blen
 448  * size of data in single frame, otherwise send multiple FC
 449  * frames of max FC frame payload supported by target port.
 450  *
 451  * Returns : 0 for success.
 452  */
 453 static int fc_fcp_send_data(struct fc_fcp_pkt *fsp, struct fc_seq *seq,
 454                             size_t offset, size_t seq_blen)
 455 {
 456         struct fc_exch *ep;
 457         struct scsi_cmnd *sc;
 458         struct scatterlist *sg;
 459         struct fc_frame *fp = NULL;
 460         struct fc_lport *lp = fsp->lp;
 461         size_t remaining;
 462         size_t t_blen;
 463         size_t tlen;
 464         size_t sg_bytes;
 465         size_t frame_offset, fh_parm_offset;
 466         int error;
 467         void *data = NULL;
 468         void *page_addr;
 469         int using_sg = lp->sg_supp;
 470         u32 f_ctl;
 471
 472         WARN_ON(seq_blen <= 0);
 473         if (unlikely(offset + seq_blen > fsp->data_len)) {
 474                 /* this should never happen */
 475                 FC_FCP_DBG(fsp, "xfer-ready past end. seq_blen %zx "
 476                            "offset %zx\n", seq_blen, offset);
 477                 fc_fcp_send_abort(fsp);
 478                 return 0;
 479         } else if (offset != fsp->xfer_len) {
 480                 /* Out of Order Data Request - no problem, but unexpected. */
 481                 FC_FCP_DBG(fsp, "xfer-ready non-contiguous. "
 482                            "seq_blen %zx offset %zx\n", seq_blen, offset);
 483         }
 484
 485         /*
 486          * if LLD is capable of seq_offload then set transport
 487          * burst length (t_blen) to seq_blen, otherwise set t_blen
 488          * to max FC frame payload previously set in fsp->max_payload.
 489          */
 490         t_blen = fsp->max_payload;
 491         if (lp->seq_offload) {
 492                 t_blen = min(seq_blen, (size_t)lp->lso_max);
 493                 FC_FCP_DBG(fsp, "fsp=%p:lso:blen=%zx lso_max=0x%x t_blen=%zx\n",
 494                            fsp, seq_blen, lp->lso_max, t_blen);
 495         }
 496
 497         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);
 498         if (t_blen > 512)
 499                 t_blen &= ~(512 - 1);   /* round down to block size */
 500         WARN_ON(t_blen < FC_MIN_MAX_PAYLOAD);   /* won't go below 256 */
 501         sc = fsp->cmd;
 502
 503         remaining = seq_blen;
 504         fh_parm_offset = frame_offset = offset;
 505         tlen = 0;
 506         seq = lp->tt.seq_start_next(seq);
 507         f_ctl = FC_FC_REL_OFF;
 508         WARN_ON(!seq);
 509
 510         sg = scsi_sglist(sc);
 511
 512         while (remaining > 0 && sg) {
 513                 if (offset >= sg->length) {
 514                         offset -= sg->length;
 515                         sg = sg_next(sg);
 516                         continue;
 517                 }
 518                 if (!fp) {
 519                         tlen = min(t_blen, remaining);
 520
 521                         /*
 522                          * TODO.  Temporary workaround.  fc_seq_send() can't
 523                          * handle odd lengths in non-linear skbs.
 524                          * This will be the final fragment only.
 525                          */
 526                         if (tlen % 4)
 527                                 using_sg = 0;
 528                         if (using_sg) {
 529                                 fp = _fc_frame_alloc(lp, 0);
 530                                 if (!fp)
 531                                         return -ENOMEM;
 532                         } else {
 533                                 fp = fc_frame_alloc(lp, tlen);
 534                                 if (!fp)
 535                                         return -ENOMEM;
 536
 537                                 data = (void *)(fr_hdr(fp)) +
 538                                         sizeof(struct fc_frame_header);
 539                         }
 540                         fh_parm_offset = frame_offset;
 541                         fr_max_payload(fp) = fsp->max_payload;
 542                 }
 543                 sg_bytes = min(tlen, sg->length - offset);
 544                 if (using_sg) {
 545                         get_page(sg_page(sg));
 546                         skb_fill_page_desc(fp_skb(fp),
 547                                            skb_shinfo(fp_skb(fp))->nr_frags,
 548                                            sg_page(sg), sg->offset + offset,
 549                                            sg_bytes);
 550                         fp_skb(fp)->data_len += sg_bytes;
 551                         fr_len(fp) += sg_bytes;
 552                         fp_skb(fp)->truesize += PAGE_SIZE;
 553                 } else {
 554                         size_t off = offset + sg->offset;
 555
 556                         /*
 557                          * The scatterlist item may be bigger than PAGE_SIZE,
 558                          * but we must not cross pages inside the kmap.
 559                          */
 560                         sg_bytes = min(sg_bytes, (size_t) (PAGE_SIZE -
 561                                                            (off & ~PAGE_MASK)));
 562                         page_addr = kmap_atomic(sg_page(sg) +
 563                                                 (off >> PAGE_SHIFT),
 564                                                 KM_SOFTIRQ0);
 565                         memcpy(data, (char *)page_addr + (off & ~PAGE_MASK),
 566                                sg_bytes);
 567                         kunmap_atomic(page_addr, KM_SOFTIRQ0);
 568                         data += sg_bytes;
 569                 }
 570                 offset += sg_bytes;
 571                 frame_offset += sg_bytes;
 572                 tlen -= sg_bytes;
 573                 remaining -= sg_bytes;
 574
 575                 if (tlen)
 576                         continue;
 577
 578                 /*
 579                  * Send sequence with transfer sequence initiative in case
 580                  * this is last FCP frame of the sequence.
 581                  */
 582                 if (remaining == 0)
 583                         f_ctl |= FC_FC_SEQ_INIT | FC_FC_END_SEQ;
 584
 585                 ep = fc_seq_exch(seq);
 586                 fc_fill_fc_hdr(fp, FC_RCTL_DD_SOL_DATA, ep->did, ep->sid,
 587                                FC_TYPE_FCP, f_ctl, fh_parm_offset);
 588
 589                 /*
 590                  * send fragment using for a sequence.
 591                  */
 592                 error = lp->tt.seq_send(lp, seq, fp);
 593                 if (error) {
 594                         WARN_ON(1);             /* send error should be rare */
 595                         fc_fcp_retry_cmd(fsp);
 596                         return 0;
 597                 }
 598                 fp = NULL;
 599         }
 600         fsp->xfer_len += seq_blen;      /* premature count? */
 601         return 0;
 602 }
 603
 604 static void fc_fcp_abts_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 605 {
 606         int ba_done = 1;
 607         struct fc_ba_rjt *brp;
 608         struct fc_frame_header *fh;
 609
 610         fh = fc_frame_header_get(fp);
 611         switch (fh->fh_r_ctl) {
 612         case FC_RCTL_BA_ACC:
 613                 break;
 614         case FC_RCTL_BA_RJT:
 615                 brp = fc_frame_payload_get(fp, sizeof(*brp));
 616                 if (brp && brp->br_reason == FC_BA_RJT_LOG_ERR)
 617                         break;
 618                 /* fall thru */
 619         default:
 620                 /*
 621                  * we will let the command timeout
 622                  * and scsi-ml recover in this case,
 623                  * therefore cleared the ba_done flag.
 624                  */
 625                 ba_done = 0;
 626         }
 627
 628         if (ba_done) {
 629                 fsp->state |= FC_SRB_ABORTED;
 630                 fsp->state &= ~FC_SRB_ABORT_PENDING;
 631
 632                 if (fsp->wait_for_comp)
 633                         complete(&fsp->tm_done);
 634                 else
 635                         fc_fcp_complete_locked(fsp);
 636         }
 637 }
 638
 639 /**
 640  * fc_fcp_reduce_can_queue() - drop can_queue
 641  * @lp: lport to drop queueing for
 642  *
 643  * If we are getting memory allocation failures, then we may
 644  * be trying to execute too many commands. We let the running
 645  * commands complete or timeout, then try again with a reduced
 646  * can_queue. Eventually we will hit the point where we run
 647  * on all reserved structs.
 648  */
 649 static void fc_fcp_reduce_can_queue(struct fc_lport *lp)
 650 {
 651         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 652         unsigned long flags;
 653         int can_queue;
 654
 655         spin_lock_irqsave(lp->host->host_lock, flags);
 656         if (si->throttled)
 657                 goto done;
 658         si->throttled = 1;
 659
 660         can_queue = lp->host->can_queue;
 661         can_queue >>= 1;
 662         if (!can_queue)
 663                 can_queue = 1;
 664         lp->host->can_queue = can_queue;
 665         shost_printk(KERN_ERR, lp->host, "libfc: Could not allocate frame.\n"
 666                      "Reducing can_queue to %d.\n", can_queue);
 667 done:
 668         spin_unlock_irqrestore(lp->host->host_lock, flags);
 669 }
 670
 671 /**
 672  * fc_fcp_recv() - Reveive FCP frames
 673  * @seq: The sequence the frame is on
 674  * @fp: The FC frame
 675  * @arg: The related FCP packet
 676  *
 677  * Return   : None
 678  * Context  : called from Soft IRQ context
 679  *            can not called holding list lock
 680  */
 681 static void fc_fcp_recv(struct fc_seq *seq, struct fc_frame *fp, void *arg)
 682 {
 683         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
 684         struct fc_lport *lport = fsp->lp;
 685         struct fc_frame_header *fh;
 686         struct fcp_txrdy *dd;
 687         u8 r_ctl;
 688         int rc = 0;
 689
 690         if (IS_ERR(fp))
 691                 goto errout;
 692
 693         fh = fc_frame_header_get(fp);
 694         r_ctl = fh->fh_r_ctl;
 695
 696         if (!(lport->state & LPORT_ST_READY))
 697                 goto out;
 698         if (fc_fcp_lock_pkt(fsp))
 699                 goto out;
 700         fsp->last_pkt_time = jiffies;
 701
 702         if (fh->fh_type == FC_TYPE_BLS) {
 703                 fc_fcp_abts_resp(fsp, fp);
 704                 goto unlock;
 705         }
 706
 707         if (fsp->state & (FC_SRB_ABORTED | FC_SRB_ABORT_PENDING))
 708                 goto unlock;
 709
 710         if (r_ctl == FC_RCTL_DD_DATA_DESC) {
 711                 /*
 712                  * received XFER RDY from the target
 713                  * need to send data to the target
 714                  */
 715                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 716                 dd = fc_frame_payload_get(fp, sizeof(*dd));
 717                 WARN_ON(!dd);
 718
 719                 rc = fc_fcp_send_data(fsp, seq,
 720                                       (size_t) ntohl(dd->ft_data_ro),
 721                                       (size_t) ntohl(dd->ft_burst_len));
 722                 if (!rc)
 723                         seq->rec_data = fsp->xfer_len;
 724                 else if (rc == -ENOMEM)
 725                         fsp->state |= FC_SRB_NOMEM;
 726         } else if (r_ctl == FC_RCTL_DD_SOL_DATA) {
 727                 /*
 728                  * received a DATA frame
 729                  * next we will copy the data to the system buffer
 730                  */
 731                 WARN_ON(fr_len(fp) < sizeof(*fh));      /* len may be 0 */
 732                 fc_fcp_recv_data(fsp, fp);
 733                 seq->rec_data = fsp->xfer_contig_end;
 734         } else if (r_ctl == FC_RCTL_DD_CMD_STATUS) {
 735                 WARN_ON(fr_flags(fp) & FCPHF_CRC_UNCHECKED);
 736
 737                 fc_fcp_resp(fsp, fp);
 738         } else {
 739                 FC_FCP_DBG(fsp, "unexpected frame.  r_ctl %x\n", r_ctl);
 740         }
 741 unlock:
 742         fc_fcp_unlock_pkt(fsp);
 743 out:
 744         fc_frame_free(fp);
 745 errout:
 746         if (IS_ERR(fp))
 747                 fc_fcp_error(fsp, fp);
 748         else if (rc == -ENOMEM)
 749                 fc_fcp_reduce_can_queue(lport);
 750 }
 751
 752 static void fc_fcp_resp(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 753 {
 754         struct fc_frame_header *fh;
 755         struct fcp_resp *fc_rp;
 756         struct fcp_resp_ext *rp_ex;
 757         struct fcp_resp_rsp_info *fc_rp_info;
 758         u32 plen;
 759         u32 expected_len;
 760         u32 respl = 0;
 761         u32 snsl = 0;
 762         u8 flags = 0;
 763
 764         plen = fr_len(fp);
 765         fh = (struct fc_frame_header *)fr_hdr(fp);
 766         if (unlikely(plen < sizeof(*fh) + sizeof(*fc_rp)))
 767                 goto len_err;
 768         plen -= sizeof(*fh);
 769         fc_rp = (struct fcp_resp *)(fh + 1);
 770         fsp->cdb_status = fc_rp->fr_status;
 771         flags = fc_rp->fr_flags;
 772         fsp->scsi_comp_flags = flags;
 773         expected_len = fsp->data_len;
 774
 775         /* if ddp, update xfer len */
 776         fc_fcp_ddp_done(fsp);
 777
 778         if (unlikely((flags & ~FCP_CONF_REQ) || fc_rp->fr_status)) {
 779                 rp_ex = (void *)(fc_rp + 1);
 780                 if (flags & (FCP_RSP_LEN_VAL | FCP_SNS_LEN_VAL)) {
 781                         if (plen < sizeof(*fc_rp) + sizeof(*rp_ex))
 782                                 goto len_err;
 783                         fc_rp_info = (struct fcp_resp_rsp_info *)(rp_ex + 1);
 784                         if (flags & FCP_RSP_LEN_VAL) {
 785                                 respl = ntohl(rp_ex->fr_rsp_len);
 786                                 if (respl != sizeof(*fc_rp_info))
 787                                         goto len_err;
 788                                 if (fsp->wait_for_comp) {
 789                                         /* Abuse cdb_status for rsp code */
 790                                         fsp->cdb_status = fc_rp_info->rsp_code;
 791                                         complete(&fsp->tm_done);
 792                                         /*
 793                                          * tmfs will not have any scsi cmd so
 794                                          * exit here
 795                                          */
 796                                         return;
 797                                 } else
 798                                         goto err;
 799                         }
 800                         if (flags & FCP_SNS_LEN_VAL) {
 801                                 snsl = ntohl(rp_ex->fr_sns_len);
 802                                 if (snsl > SCSI_SENSE_BUFFERSIZE)
 803                                         snsl = SCSI_SENSE_BUFFERSIZE;
 804                                 memcpy(fsp->cmd->sense_buffer,
 805                                        (char *)fc_rp_info + respl, snsl);
 806                         }
 807                 }
 808                 if (flags & (FCP_RESID_UNDER | FCP_RESID_OVER)) {
 809                         if (plen < sizeof(*fc_rp) + sizeof(rp_ex->fr_resid))
 810                                 goto len_err;
 811                         if (flags & FCP_RESID_UNDER) {
 812                                 fsp->scsi_resid = ntohl(rp_ex->fr_resid);
 813                                 /*
 814                                  * The cmnd->underflow is the minimum number of
 815                                  * bytes that must be transfered for this
 816                                  * command.  Provided a sense condition is not
 817                                  * present, make sure the actual amount
 818                                  * transferred is at least the underflow value
 819                                  * or fail.
 820                                  */
 821                                 if (!(flags & FCP_SNS_LEN_VAL) &&
 822                                     (fc_rp->fr_status == 0) &&
 823                                     (scsi_bufflen(fsp->cmd) -
 824                                      fsp->scsi_resid) < fsp->cmd->underflow)
 825                                         goto err;
 826                                 expected_len -= fsp->scsi_resid;
 827                         } else {
 828                                 fsp->status_code = FC_ERROR;
 829                         }
 830                 }
 831         }
 832         fsp->state |= FC_SRB_RCV_STATUS;
 833
 834         /*
 835          * Check for missing or extra data frames.
 836          */
 837         if (unlikely(fsp->xfer_len != expected_len)) {
 838                 if (fsp->xfer_len < expected_len) {
 839                         /*
 840                          * Some data may be queued locally,
 841                          * Wait a at least one jiffy to see if it is delivered.
 842                          * If this expires without data, we may do SRR.
 843                          */
 844                         fc_fcp_timer_set(fsp, 2);
 845                         return;
 846                 }
 847                 fsp->status_code = FC_DATA_OVRRUN;
 848                 FC_FCP_DBG(fsp, "tgt %6x xfer len %zx greater than expected, "
 849                            "len %x, data len %x\n",
 850                            fsp->rport->port_id,
 851                            fsp->xfer_len, expected_len, fsp->data_len);
 852         }
 853         fc_fcp_complete_locked(fsp);
 854         return;
 855
 856 len_err:
 857         FC_FCP_DBG(fsp, "short FCP response. flags 0x%x len %u respl %u "
 858                    "snsl %u\n", flags, fr_len(fp), respl, snsl);
 859 err:
 860         fsp->status_code = FC_ERROR;
 861         fc_fcp_complete_locked(fsp);
 862 }
 863
 864 /**
 865  * fc_fcp_complete_locked() - complete processing of a fcp packet
 866  * @fsp:        fcp packet
 867  *
 868  * This function may sleep if a timer is pending. The packet lock must be
 869  * held, and the host lock must not be held.
 870  */
 871 static void fc_fcp_complete_locked(struct fc_fcp_pkt *fsp)
 872 {
 873         struct fc_lport *lp = fsp->lp;
 874         struct fc_seq *seq;
 875         struct fc_exch *ep;
 876         u32 f_ctl;
 877
 878         if (fsp->state & FC_SRB_ABORT_PENDING)
 879                 return;
 880
 881         if (fsp->state & FC_SRB_ABORTED) {
 882                 if (!fsp->status_code)
 883                         fsp->status_code = FC_CMD_ABORTED;
 884         } else {
 885                 /*
 886                  * Test for transport underrun, independent of response
 887                  * underrun status.
 888                  */
 889                 if (fsp->xfer_len < fsp->data_len && !fsp->io_status &&
 890                     (!(fsp->scsi_comp_flags & FCP_RESID_UNDER) ||
 891                      fsp->xfer_len < fsp->data_len - fsp->scsi_resid)) {
 892                         fsp->status_code = FC_DATA_UNDRUN;
 893                         fsp->io_status = 0;
 894                 }
 895         }
 896
 897         seq = fsp->seq_ptr;
 898         if (seq) {
 899                 fsp->seq_ptr = NULL;
 900                 if (unlikely(fsp->scsi_comp_flags & FCP_CONF_REQ)) {
 901                         struct fc_frame *conf_frame;
 902                         struct fc_seq *csp;
 903
 904                         csp = lp->tt.seq_start_next(seq);
 905                         conf_frame = fc_frame_alloc(fsp->lp, 0);
 906                         if (conf_frame) {
 907                                 f_ctl = FC_FC_SEQ_INIT;
 908                                 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
 909                                 ep = fc_seq_exch(seq);
 910                                 fc_fill_fc_hdr(conf_frame, FC_RCTL_DD_SOL_CTL,
 911                                                ep->did, ep->sid,
 912                                                FC_TYPE_FCP, f_ctl, 0);
 913                                 lp->tt.seq_send(lp, csp, conf_frame);
 914                         }
 915                 }
 916                 lp->tt.exch_done(seq);
 917         }
 918         fc_io_compl(fsp);
 919 }
 920
 921 static void fc_fcp_cleanup_cmd(struct fc_fcp_pkt *fsp, int error)
 922 {
 923         struct fc_lport *lp = fsp->lp;
 924
 925         if (fsp->seq_ptr) {
 926                 lp->tt.exch_done(fsp->seq_ptr);
 927                 fsp->seq_ptr = NULL;
 928         }
 929         fsp->status_code = error;
 930 }
 931
 932 /**
 933  * fc_fcp_cleanup_each_cmd() - Cleanup active commads
 934  * @lp:         logical port
 935  * @id:         target id
 936  * @lun:        lun
 937  * @error:      fsp status code
 938  *
 939  * If lun or id is -1, they are ignored.
 940  */
 941 static void fc_fcp_cleanup_each_cmd(struct fc_lport *lp, unsigned int id,
 942                                     unsigned int lun, int error)
 943 {
 944         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 945         struct fc_fcp_pkt *fsp;
 946         struct scsi_cmnd *sc_cmd;
 947         unsigned long flags;
 948
 949         spin_lock_irqsave(lp->host->host_lock, flags);
 950 restart:
 951         list_for_each_entry(fsp, &si->scsi_pkt_queue, list) {
 952                 sc_cmd = fsp->cmd;
 953                 if (id != -1 && scmd_id(sc_cmd) != id)
 954                         continue;
 955
 956                 if (lun != -1 && sc_cmd->device->lun != lun)
 957                         continue;
 958
 959                 fc_fcp_pkt_hold(fsp);
 960                 spin_unlock_irqrestore(lp->host->host_lock, flags);
 961
 962                 if (!fc_fcp_lock_pkt(fsp)) {
 963                         fc_fcp_cleanup_cmd(fsp, error);
 964                         fc_io_compl(fsp);
 965                         fc_fcp_unlock_pkt(fsp);
 966                 }
 967
 968                 fc_fcp_pkt_release(fsp);
 969                 spin_lock_irqsave(lp->host->host_lock, flags);
 970                 /*
 971                  * while we dropped the lock multiple pkts could
 972                  * have been released, so we have to start over.
 973                  */
 974                 goto restart;
 975         }
 976         spin_unlock_irqrestore(lp->host->host_lock, flags);
 977 }
 978
 979 static void fc_fcp_abort_io(struct fc_lport *lp)
 980 {
 981         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_HRD_ERROR);
 982 }
 983
 984 /**
 985  * fc_fcp_pkt_send() - send a fcp packet to the lower level.
 986  * @lp:         fc lport
 987  * @fsp:        fc packet.
 988  *
 989  * This is called by upper layer protocol.
 990  * Return   : zero for success and -1 for failure
 991  * Context  : called from queuecommand which can be called from process
 992  *            or scsi soft irq.
 993  * Locks    : called with the host lock and irqs disabled.
 994  */
 995 static int fc_fcp_pkt_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
 996 {
 997         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
 998         int rc;
 999
1000         fsp->cmd->SCp.ptr = (char *)fsp;
1001         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1002         fsp->cdb_cmd.fc_flags = fsp->req_flags & ~FCP_CFL_LEN_MASK;
1003
1004         int_to_scsilun(fsp->cmd->device->lun,
1005                        (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1006         memcpy(fsp->cdb_cmd.fc_cdb, fsp->cmd->cmnd, fsp->cmd->cmd_len);
1007         list_add_tail(&fsp->list, &si->scsi_pkt_queue);
1008
1009         spin_unlock_irq(lp->host->host_lock);
1010         rc = lp->tt.fcp_cmd_send(lp, fsp, fc_fcp_recv);
1011         spin_lock_irq(lp->host->host_lock);
1012         if (rc)
1013                 list_del(&fsp->list);
1014
1015         return rc;
1016 }
1017
1018 static int fc_fcp_cmd_send(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1019                            void (*resp)(struct fc_seq *,
1020                                         struct fc_frame *fp,
1021                                         void *arg))
1022 {
1023         struct fc_frame *fp;
1024         struct fc_seq *seq;
1025         struct fc_rport *rport;
1026         struct fc_rport_libfc_priv *rp;
1027         const size_t len = sizeof(fsp->cdb_cmd);
1028         int rc = 0;
1029
1030         if (fc_fcp_lock_pkt(fsp))
1031                 return 0;
1032
1033         fp = fc_frame_alloc(lp, sizeof(fsp->cdb_cmd));
1034         if (!fp) {
1035                 rc = -1;
1036                 goto unlock;
1037         }
1038
1039         memcpy(fc_frame_payload_get(fp, len), &fsp->cdb_cmd, len);
1040         fr_fsp(fp) = fsp;
1041         rport = fsp->rport;
1042         fsp->max_payload = rport->maxframe_size;
1043         rp = rport->dd_data;
1044
1045         fc_fill_fc_hdr(fp, FC_RCTL_DD_UNSOL_CMD, rport->port_id,
1046                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1047                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1048
1049         seq = lp->tt.exch_seq_send(lp, fp, resp, fc_fcp_pkt_destroy, fsp, 0);
1050         if (!seq) {
1051                 fc_frame_free(fp);
1052                 rc = -1;
1053                 goto unlock;
1054         }
1055         fsp->last_pkt_time = jiffies;
1056         fsp->seq_ptr = seq;
1057         fc_fcp_pkt_hold(fsp);   /* hold for fc_fcp_pkt_destroy */
1058
1059         setup_timer(&fsp->timer, fc_fcp_timeout, (unsigned long)fsp);
1060         fc_fcp_timer_set(fsp,
1061                          (fsp->tgt_flags & FC_RP_FLAGS_REC_SUPPORTED) ?
1062                          FC_SCSI_REC_TOV : FC_SCSI_ER_TIMEOUT);
1063 unlock:
1064         fc_fcp_unlock_pkt(fsp);
1065         return rc;
1066 }
1067
1068 /*
1069  * transport error handler
1070  */
1071 static void fc_fcp_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1072 {
1073         int error = PTR_ERR(fp);
1074
1075         if (fc_fcp_lock_pkt(fsp))
1076                 return;
1077
1078         if (error == -FC_EX_CLOSED) {
1079                 fc_fcp_retry_cmd(fsp);
1080                 goto unlock;
1081         }
1082
1083         /*
1084          * clear abort pending, because the lower layer
1085          * decided to force completion.
1086          */
1087         fsp->state &= ~FC_SRB_ABORT_PENDING;
1088         fsp->status_code = FC_CMD_PLOGO;
1089         fc_fcp_complete_locked(fsp);
1090 unlock:
1091         fc_fcp_unlock_pkt(fsp);
1092 }
1093
1094 /*
1095  * Scsi abort handler- calls to send an abort
1096  * and then wait for abort completion
1097  */
1098 static int fc_fcp_pkt_abort(struct fc_lport *lp, struct fc_fcp_pkt *fsp)
1099 {
1100         int rc = FAILED;
1101
1102         if (fc_fcp_send_abort(fsp))
1103                 return FAILED;
1104
1105         init_completion(&fsp->tm_done);
1106         fsp->wait_for_comp = 1;
1107
1108         spin_unlock_bh(&fsp->scsi_pkt_lock);
1109         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1110         spin_lock_bh(&fsp->scsi_pkt_lock);
1111         fsp->wait_for_comp = 0;
1112
1113         if (!rc) {
1114                 FC_FCP_DBG(fsp, "target abort cmd  failed\n");
1115                 rc = FAILED;
1116         } else if (fsp->state & FC_SRB_ABORTED) {
1117                 FC_FCP_DBG(fsp, "target abort cmd  passed\n");
1118                 rc = SUCCESS;
1119                 fc_fcp_complete_locked(fsp);
1120         }
1121
1122         return rc;
1123 }
1124
1125 /*
1126  * Retry LUN reset after resource allocation failed.
1127  */
1128 static void fc_lun_reset_send(unsigned long data)
1129 {
1130         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1131         struct fc_lport *lp = fsp->lp;
1132         if (lp->tt.fcp_cmd_send(lp, fsp, fc_tm_done)) {
1133                 if (fsp->recov_retry++ >= FC_MAX_RECOV_RETRY)
1134                         return;
1135                 if (fc_fcp_lock_pkt(fsp))
1136                         return;
1137                 setup_timer(&fsp->timer, fc_lun_reset_send, (unsigned long)fsp);
1138                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1139                 fc_fcp_unlock_pkt(fsp);
1140         }
1141 }
1142
1143 /*
1144  * Scsi device reset handler- send a LUN RESET to the device
1145  * and wait for reset reply
1146  */
1147 static int fc_lun_reset(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
1148                         unsigned int id, unsigned int lun)
1149 {
1150         int rc;
1151
1152         fsp->cdb_cmd.fc_dl = htonl(fsp->data_len);
1153         fsp->cdb_cmd.fc_tm_flags = FCP_TMF_LUN_RESET;
1154         int_to_scsilun(lun, (struct scsi_lun *)fsp->cdb_cmd.fc_lun);
1155
1156         fsp->wait_for_comp = 1;
1157         init_completion(&fsp->tm_done);
1158
1159         fc_lun_reset_send((unsigned long)fsp);
1160
1161         /*
1162          * wait for completion of reset
1163          * after that make sure all commands are terminated
1164          */
1165         rc = wait_for_completion_timeout(&fsp->tm_done, FC_SCSI_TM_TOV);
1166
1167         spin_lock_bh(&fsp->scsi_pkt_lock);
1168         fsp->state |= FC_SRB_COMPL;
1169         spin_unlock_bh(&fsp->scsi_pkt_lock);
1170
1171         del_timer_sync(&fsp->timer);
1172
1173         spin_lock_bh(&fsp->scsi_pkt_lock);
1174         if (fsp->seq_ptr) {
1175                 lp->tt.exch_done(fsp->seq_ptr);
1176                 fsp->seq_ptr = NULL;
1177         }
1178         fsp->wait_for_comp = 0;
1179         spin_unlock_bh(&fsp->scsi_pkt_lock);
1180
1181         if (!rc) {
1182                 FC_SCSI_DBG(lp, "lun reset failed\n");
1183                 return FAILED;
1184         }
1185
1186         /* cdb_status holds the tmf's rsp code */
1187         if (fsp->cdb_status != FCP_TMF_CMPL)
1188                 return FAILED;
1189
1190         FC_SCSI_DBG(lp, "lun reset to lun %u completed\n", lun);
1191         fc_fcp_cleanup_each_cmd(lp, id, lun, FC_CMD_ABORTED);
1192         return SUCCESS;
1193 }
1194
1195 /*
1196  * Task Managment response handler
1197  */
1198 static void fc_tm_done(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1199 {
1200         struct fc_fcp_pkt *fsp = arg;
1201         struct fc_frame_header *fh;
1202
1203         if (IS_ERR(fp)) {
1204                 /*
1205                  * If there is an error just let it timeout or wait
1206                  * for TMF to be aborted if it timedout.
1207                  *
1208                  * scsi-eh will escalate for when either happens.
1209                  */
1210                 return;
1211         }
1212
1213         if (fc_fcp_lock_pkt(fsp))
1214                 return;
1215
1216         /*
1217          * raced with eh timeout handler.
1218          */
1219         if (!fsp->seq_ptr || !fsp->wait_for_comp) {
1220                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1221                 return;
1222         }
1223
1224         fh = fc_frame_header_get(fp);
1225         if (fh->fh_type != FC_TYPE_BLS)
1226                 fc_fcp_resp(fsp, fp);
1227         fsp->seq_ptr = NULL;
1228         fsp->lp->tt.exch_done(seq);
1229         fc_frame_free(fp);
1230         fc_fcp_unlock_pkt(fsp);
1231 }
1232
1233 static void fc_fcp_cleanup(struct fc_lport *lp)
1234 {
1235         fc_fcp_cleanup_each_cmd(lp, -1, -1, FC_ERROR);
1236 }
1237
1238 /*
1239  * fc_fcp_timeout: called by OS timer function.
1240  *
1241  * The timer has been inactivated and must be reactivated if desired
1242  * using fc_fcp_timer_set().
1243  *
1244  * Algorithm:
1245  *
1246  * If REC is supported, just issue it, and return.  The REC exchange will
1247  * complete or time out, and recovery can continue at that point.
1248  *
1249  * Otherwise, if the response has been received without all the data,
1250  * it has been ER_TIMEOUT since the response was received.
1251  *
1252  * If the response has not been received,
1253  * we see if data was received recently.  If it has been, we continue waiting,
1254  * otherwise, we abort the command.
1255  */
1256 static void fc_fcp_timeout(unsigned long data)
1257 {
1258         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)data;
1259         struct fc_rport *rport = fsp->rport;
1260         struct fc_rport_libfc_priv *rp = rport->dd_data;
1261
1262         if (fc_fcp_lock_pkt(fsp))
1263                 return;
1264
1265         if (fsp->cdb_cmd.fc_tm_flags)
1266                 goto unlock;
1267
1268         fsp->state |= FC_SRB_FCP_PROCESSING_TMO;
1269
1270         if (rp->flags & FC_RP_FLAGS_REC_SUPPORTED)
1271                 fc_fcp_rec(fsp);
1272         else if (time_after_eq(fsp->last_pkt_time + (FC_SCSI_ER_TIMEOUT / 2),
1273                                jiffies))
1274                 fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1275         else if (fsp->state & FC_SRB_RCV_STATUS)
1276                 fc_fcp_complete_locked(fsp);
1277         else
1278                 fc_timeout_error(fsp);
1279         fsp->state &= ~FC_SRB_FCP_PROCESSING_TMO;
1280 unlock:
1281         fc_fcp_unlock_pkt(fsp);
1282 }
1283
1284 /*
1285  * Send a REC ELS request
1286  */
1287 static void fc_fcp_rec(struct fc_fcp_pkt *fsp)
1288 {
1289         struct fc_lport *lp;
1290         struct fc_frame *fp;
1291         struct fc_rport *rport;
1292         struct fc_rport_libfc_priv *rp;
1293
1294         lp = fsp->lp;
1295         rport = fsp->rport;
1296         rp = rport->dd_data;
1297         if (!fsp->seq_ptr || rp->rp_state != RPORT_ST_READY) {
1298                 fsp->status_code = FC_HRD_ERROR;
1299                 fsp->io_status = 0;
1300                 fc_fcp_complete_locked(fsp);
1301                 return;
1302         }
1303         fp = fc_frame_alloc(lp, sizeof(struct fc_els_rec));
1304         if (!fp)
1305                 goto retry;
1306
1307         fr_seq(fp) = fsp->seq_ptr;
1308         fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, rport->port_id,
1309                        fc_host_port_id(rp->local_port->host), FC_TYPE_ELS,
1310                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1311         if (lp->tt.elsct_send(lp, rport->port_id, fp, ELS_REC, fc_fcp_rec_resp,
1312                               fsp, jiffies_to_msecs(FC_SCSI_REC_TOV))) {
1313                 fc_fcp_pkt_hold(fsp);           /* hold while REC outstanding */
1314                 return;
1315         }
1316         fc_frame_free(fp);
1317 retry:
1318         if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1319                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1320         else
1321                 fc_timeout_error(fsp);
1322 }
1323
1324 /*
1325  * Receive handler for REC ELS frame
1326  * if it is a reject then let the scsi layer to handle
1327  * the timeout. if it is a LS_ACC then if the io was not completed
1328  * then set the timeout and return otherwise complete the exchange
1329  * and tell the scsi layer to restart the I/O.
1330  */
1331 static void fc_fcp_rec_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1332 {
1333         struct fc_fcp_pkt *fsp = (struct fc_fcp_pkt *)arg;
1334         struct fc_els_rec_acc *recp;
1335         struct fc_els_ls_rjt *rjt;
1336         u32 e_stat;
1337         u8 opcode;
1338         u32 offset;
1339         enum dma_data_direction data_dir;
1340         enum fc_rctl r_ctl;
1341         struct fc_rport_libfc_priv *rp;
1342
1343         if (IS_ERR(fp)) {
1344                 fc_fcp_rec_error(fsp, fp);
1345                 return;
1346         }
1347
1348         if (fc_fcp_lock_pkt(fsp))
1349                 goto out;
1350
1351         fsp->recov_retry = 0;
1352         opcode = fc_frame_payload_op(fp);
1353         if (opcode == ELS_LS_RJT) {
1354                 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1355                 switch (rjt->er_reason) {
1356                 default:
1357                         FC_FCP_DBG(fsp, "device %x unexpected REC reject "
1358                                    "reason %d expl %d\n",
1359                                    fsp->rport->port_id, rjt->er_reason,
1360                                    rjt->er_explan);
1361                         /* fall through */
1362                 case ELS_RJT_UNSUP:
1363                         FC_FCP_DBG(fsp, "device does not support REC\n");
1364                         rp = fsp->rport->dd_data;
1365                         /*
1366                          * if we do not spport RECs or got some bogus
1367                          * reason then resetup timer so we check for
1368                          * making progress.
1369                          */
1370                         rp->flags &= ~FC_RP_FLAGS_REC_SUPPORTED;
1371                         fc_fcp_timer_set(fsp, FC_SCSI_ER_TIMEOUT);
1372                         break;
1373                 case ELS_RJT_LOGIC:
1374                 case ELS_RJT_UNAB:
1375                         /*
1376                          * If no data transfer, the command frame got dropped
1377                          * so we just retry.  If data was transferred, we
1378                          * lost the response but the target has no record,
1379                          * so we abort and retry.
1380                          */
1381                         if (rjt->er_explan == ELS_EXPL_OXID_RXID &&
1382                             fsp->xfer_len == 0) {
1383                                 fc_fcp_retry_cmd(fsp);
1384                                 break;
1385                         }
1386                         fc_timeout_error(fsp);
1387                         break;
1388                 }
1389         } else if (opcode == ELS_LS_ACC) {
1390                 if (fsp->state & FC_SRB_ABORTED)
1391                         goto unlock_out;
1392
1393                 data_dir = fsp->cmd->sc_data_direction;
1394                 recp = fc_frame_payload_get(fp, sizeof(*recp));
1395                 offset = ntohl(recp->reca_fc4value);
1396                 e_stat = ntohl(recp->reca_e_stat);
1397
1398                 if (e_stat & ESB_ST_COMPLETE) {
1399
1400                         /*
1401                          * The exchange is complete.
1402                          *
1403                          * For output, we must've lost the response.
1404                          * For input, all data must've been sent.
1405                          * We lost may have lost the response
1406                          * (and a confirmation was requested) and maybe
1407                          * some data.
1408                          *
1409                          * If all data received, send SRR
1410                          * asking for response.  If partial data received,
1411                          * or gaps, SRR requests data at start of gap.
1412                          * Recovery via SRR relies on in-order-delivery.
1413                          */
1414                         if (data_dir == DMA_TO_DEVICE) {
1415                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1416                         } else if (fsp->xfer_contig_end == offset) {
1417                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1418                         } else {
1419                                 offset = fsp->xfer_contig_end;
1420                                 r_ctl = FC_RCTL_DD_SOL_DATA;
1421                         }
1422                         fc_fcp_srr(fsp, r_ctl, offset);
1423                 } else if (e_stat & ESB_ST_SEQ_INIT) {
1424
1425                         /*
1426                          * The remote port has the initiative, so just
1427                          * keep waiting for it to complete.
1428                          */
1429                         fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1430                 } else {
1431
1432                         /*
1433                          * The exchange is incomplete, we have seq. initiative.
1434                          * Lost response with requested confirmation,
1435                          * lost confirmation, lost transfer ready or
1436                          * lost write data.
1437                          *
1438                          * For output, if not all data was received, ask
1439                          * for transfer ready to be repeated.
1440                          *
1441                          * If we received or sent all the data, send SRR to
1442                          * request response.
1443                          *
1444                          * If we lost a response, we may have lost some read
1445                          * data as well.
1446                          */
1447                         r_ctl = FC_RCTL_DD_SOL_DATA;
1448                         if (data_dir == DMA_TO_DEVICE) {
1449                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1450                                 if (offset < fsp->data_len)
1451                                         r_ctl = FC_RCTL_DD_DATA_DESC;
1452                         } else if (offset == fsp->xfer_contig_end) {
1453                                 r_ctl = FC_RCTL_DD_CMD_STATUS;
1454                         } else if (fsp->xfer_contig_end < offset) {
1455                                 offset = fsp->xfer_contig_end;
1456                         }
1457                         fc_fcp_srr(fsp, r_ctl, offset);
1458                 }
1459         }
1460 unlock_out:
1461         fc_fcp_unlock_pkt(fsp);
1462 out:
1463         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1464         fc_frame_free(fp);
1465 }
1466
1467 /*
1468  * Handle error response or timeout for REC exchange.
1469  */
1470 static void fc_fcp_rec_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1471 {
1472         int error = PTR_ERR(fp);
1473
1474         if (fc_fcp_lock_pkt(fsp))
1475                 goto out;
1476
1477         switch (error) {
1478         case -FC_EX_CLOSED:
1479                 fc_fcp_retry_cmd(fsp);
1480                 break;
1481
1482         default:
1483                 FC_FCP_DBG(fsp, "REC %p fid %x error unexpected error %d\n",
1484                            fsp, fsp->rport->port_id, error);
1485                 fsp->status_code = FC_CMD_PLOGO;
1486                 /* fall through */
1487
1488         case -FC_EX_TIMEOUT:
1489                 /*
1490                  * Assume REC or LS_ACC was lost.
1491                  * The exchange manager will have aborted REC, so retry.
1492                  */
1493                 FC_FCP_DBG(fsp, "REC fid %x error error %d retry %d/%d\n",
1494                            fsp->rport->port_id, error, fsp->recov_retry,
1495                            FC_MAX_RECOV_RETRY);
1496                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1497                         fc_fcp_rec(fsp);
1498                 else
1499                         fc_timeout_error(fsp);
1500                 break;
1501         }
1502         fc_fcp_unlock_pkt(fsp);
1503 out:
1504         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding REC */
1505 }
1506
1507 /*
1508  * Time out error routine:
1509  * abort's the I/O close the exchange and
1510  * send completion notification to scsi layer
1511  */
1512 static void fc_timeout_error(struct fc_fcp_pkt *fsp)
1513 {
1514         fsp->status_code = FC_CMD_TIME_OUT;
1515         fsp->cdb_status = 0;
1516         fsp->io_status = 0;
1517         /*
1518          * if this fails then we let the scsi command timer fire and
1519          * scsi-ml escalate.
1520          */
1521         fc_fcp_send_abort(fsp);
1522 }
1523
1524 /*
1525  * Sequence retransmission request.
1526  * This is called after receiving status but insufficient data, or
1527  * when expecting status but the request has timed out.
1528  */
1529 static void fc_fcp_srr(struct fc_fcp_pkt *fsp, enum fc_rctl r_ctl, u32 offset)
1530 {
1531         struct fc_lport *lp = fsp->lp;
1532         struct fc_rport *rport;
1533         struct fc_rport_libfc_priv *rp;
1534         struct fc_exch *ep = fc_seq_exch(fsp->seq_ptr);
1535         struct fc_seq *seq;
1536         struct fcp_srr *srr;
1537         struct fc_frame *fp;
1538         u8 cdb_op;
1539
1540         rport = fsp->rport;
1541         rp = rport->dd_data;
1542         cdb_op = fsp->cdb_cmd.fc_cdb[0];
1543
1544         if (!(rp->flags & FC_RP_FLAGS_RETRY) || rp->rp_state != RPORT_ST_READY)
1545                 goto retry;                     /* shouldn't happen */
1546         fp = fc_frame_alloc(lp, sizeof(*srr));
1547         if (!fp)
1548                 goto retry;
1549
1550         srr = fc_frame_payload_get(fp, sizeof(*srr));
1551         memset(srr, 0, sizeof(*srr));
1552         srr->srr_op = ELS_SRR;
1553         srr->srr_ox_id = htons(ep->oxid);
1554         srr->srr_rx_id = htons(ep->rxid);
1555         srr->srr_r_ctl = r_ctl;
1556         srr->srr_rel_off = htonl(offset);
1557
1558         fc_fill_fc_hdr(fp, FC_RCTL_ELS4_REQ, rport->port_id,
1559                        fc_host_port_id(rp->local_port->host), FC_TYPE_FCP,
1560                        FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1561
1562         seq = lp->tt.exch_seq_send(lp, fp, fc_fcp_srr_resp, NULL,
1563                                    fsp, jiffies_to_msecs(FC_SCSI_REC_TOV));
1564         if (!seq) {
1565                 fc_frame_free(fp);
1566                 goto retry;
1567         }
1568         fsp->recov_seq = seq;
1569         fsp->xfer_len = offset;
1570         fsp->xfer_contig_end = offset;
1571         fsp->state &= ~FC_SRB_RCV_STATUS;
1572         fc_fcp_pkt_hold(fsp);           /* hold for outstanding SRR */
1573         return;
1574 retry:
1575         fc_fcp_retry_cmd(fsp);
1576 }
1577
1578 /*
1579  * Handle response from SRR.
1580  */
1581 static void fc_fcp_srr_resp(struct fc_seq *seq, struct fc_frame *fp, void *arg)
1582 {
1583         struct fc_fcp_pkt *fsp = arg;
1584         struct fc_frame_header *fh;
1585
1586         if (IS_ERR(fp)) {
1587                 fc_fcp_srr_error(fsp, fp);
1588                 return;
1589         }
1590
1591         if (fc_fcp_lock_pkt(fsp))
1592                 goto out;
1593
1594         fh = fc_frame_header_get(fp);
1595         /*
1596          * BUG? fc_fcp_srr_error calls exch_done which would release
1597          * the ep. But if fc_fcp_srr_error had got -FC_EX_TIMEOUT,
1598          * then fc_exch_timeout would be sending an abort. The exch_done
1599          * call by fc_fcp_srr_error would prevent fc_exch.c from seeing
1600          * an abort response though.
1601          */
1602         if (fh->fh_type == FC_TYPE_BLS) {
1603                 fc_fcp_unlock_pkt(fsp);
1604                 return;
1605         }
1606
1607         fsp->recov_seq = NULL;
1608         switch (fc_frame_payload_op(fp)) {
1609         case ELS_LS_ACC:
1610                 fsp->recov_retry = 0;
1611                 fc_fcp_timer_set(fsp, FC_SCSI_REC_TOV);
1612                 break;
1613         case ELS_LS_RJT:
1614         default:
1615                 fc_timeout_error(fsp);
1616                 break;
1617         }
1618         fc_fcp_unlock_pkt(fsp);
1619         fsp->lp->tt.exch_done(seq);
1620 out:
1621         fc_frame_free(fp);
1622         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1623 }
1624
1625 static void fc_fcp_srr_error(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
1626 {
1627         if (fc_fcp_lock_pkt(fsp))
1628                 goto out;
1629         fsp->lp->tt.exch_done(fsp->recov_seq);
1630         fsp->recov_seq = NULL;
1631         switch (PTR_ERR(fp)) {
1632         case -FC_EX_TIMEOUT:
1633                 if (fsp->recov_retry++ < FC_MAX_RECOV_RETRY)
1634                         fc_fcp_rec(fsp);
1635                 else
1636                         fc_timeout_error(fsp);
1637                 break;
1638         case -FC_EX_CLOSED:                     /* e.g., link failure */
1639                 /* fall through */
1640         default:
1641                 fc_fcp_retry_cmd(fsp);
1642                 break;
1643         }
1644         fc_fcp_unlock_pkt(fsp);
1645 out:
1646         fc_fcp_pkt_release(fsp);        /* drop hold for outstanding SRR */
1647 }
1648
1649 static inline int fc_fcp_lport_queue_ready(struct fc_lport *lp)
1650 {
1651         /* lock ? */
1652         return (lp->state == LPORT_ST_READY) && lp->link_up && !lp->qfull;
1653 }
1654
1655 /**
1656  * fc_queuecommand - The queuecommand function of the scsi template
1657  * @cmd:        struct scsi_cmnd to be executed
1658  * @done:       Callback function to be called when cmd is completed
1659  *
1660  * this is the i/o strategy routine, called by the scsi layer
1661  * this routine is called with holding the host_lock.
1662  */
1663 int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
1664 {
1665         struct fc_lport *lp;
1666         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1667         struct fc_fcp_pkt *fsp;
1668         struct fc_rport_libfc_priv *rp;
1669         int rval;
1670         int rc = 0;
1671         struct fcoe_dev_stats *stats;
1672
1673         lp = shost_priv(sc_cmd->device->host);
1674
1675         rval = fc_remote_port_chkready(rport);
1676         if (rval) {
1677                 sc_cmd->result = rval;
1678                 done(sc_cmd);
1679                 goto out;
1680         }
1681
1682         if (!*(struct fc_remote_port **)rport->dd_data) {
1683                 /*
1684                  * rport is transitioning from blocked/deleted to
1685                  * online
1686                  */
1687                 sc_cmd->result = DID_IMM_RETRY << 16;
1688                 done(sc_cmd);
1689                 goto out;
1690         }
1691
1692         rp = rport->dd_data;
1693
1694         if (!fc_fcp_lport_queue_ready(lp)) {
1695                 rc = SCSI_MLQUEUE_HOST_BUSY;
1696                 goto out;
1697         }
1698
1699         fsp = fc_fcp_pkt_alloc(lp, GFP_ATOMIC);
1700         if (fsp == NULL) {
1701                 rc = SCSI_MLQUEUE_HOST_BUSY;
1702                 goto out;
1703         }
1704
1705         /*
1706          * build the libfc request pkt
1707          */
1708         fsp->cmd = sc_cmd;      /* save the cmd */
1709         fsp->lp = lp;           /* save the softc ptr */
1710         fsp->rport = rport;     /* set the remote port ptr */
1711         sc_cmd->scsi_done = done;
1712
1713         /*
1714          * set up the transfer length
1715          */
1716         fsp->data_len = scsi_bufflen(sc_cmd);
1717         fsp->xfer_len = 0;
1718
1719         /*
1720          * setup the data direction
1721          */
1722         stats = fc_lport_get_stats(lp);
1723         if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
1724                 fsp->req_flags = FC_SRB_READ;
1725                 stats->InputRequests++;
1726                 stats->InputMegabytes = fsp->data_len;
1727         } else if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
1728                 fsp->req_flags = FC_SRB_WRITE;
1729                 stats->OutputRequests++;
1730                 stats->OutputMegabytes = fsp->data_len;
1731         } else {
1732                 fsp->req_flags = 0;
1733                 stats->ControlRequests++;
1734         }
1735
1736         fsp->tgt_flags = rp->flags;
1737
1738         init_timer(&fsp->timer);
1739         fsp->timer.data = (unsigned long)fsp;
1740
1741         /*
1742          * send it to the lower layer
1743          * if we get -1 return then put the request in the pending
1744          * queue.
1745          */
1746         rval = fc_fcp_pkt_send(lp, fsp);
1747         if (rval != 0) {
1748                 fsp->state = FC_SRB_FREE;
1749                 fc_fcp_pkt_release(fsp);
1750                 rc = SCSI_MLQUEUE_HOST_BUSY;
1751         }
1752 out:
1753         return rc;
1754 }
1755 EXPORT_SYMBOL(fc_queuecommand);
1756
1757 /**
1758  * fc_io_compl() -  Handle responses for completed commands
1759  * @fsp:        scsi packet
1760  *
1761  * Translates a error to a Linux SCSI error.
1762  *
1763  * The fcp packet lock must be held when calling.
1764  */
1765 static void fc_io_compl(struct fc_fcp_pkt *fsp)
1766 {
1767         struct fc_fcp_internal *si;
1768         struct scsi_cmnd *sc_cmd;
1769         struct fc_lport *lp;
1770         unsigned long flags;
1771
1772         /* release outstanding ddp context */
1773         fc_fcp_ddp_done(fsp);
1774
1775         fsp->state |= FC_SRB_COMPL;
1776         if (!(fsp->state & FC_SRB_FCP_PROCESSING_TMO)) {
1777                 spin_unlock_bh(&fsp->scsi_pkt_lock);
1778                 del_timer_sync(&fsp->timer);
1779                 spin_lock_bh(&fsp->scsi_pkt_lock);
1780         }
1781
1782         lp = fsp->lp;
1783         si = fc_get_scsi_internal(lp);
1784         spin_lock_irqsave(lp->host->host_lock, flags);
1785         if (!fsp->cmd) {
1786                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1787                 return;
1788         }
1789
1790         /*
1791          * if a command timed out while we had to try and throttle IO
1792          * and it is now getting cleaned up, then we are about to
1793          * try again so clear the throttled flag incase we get more
1794          * time outs.
1795          */
1796         if (si->throttled && fsp->state & FC_SRB_NOMEM)
1797                 si->throttled = 0;
1798
1799         sc_cmd = fsp->cmd;
1800         fsp->cmd = NULL;
1801
1802         if (!sc_cmd->SCp.ptr) {
1803                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1804                 return;
1805         }
1806
1807         CMD_SCSI_STATUS(sc_cmd) = fsp->cdb_status;
1808         switch (fsp->status_code) {
1809         case FC_COMPLETE:
1810                 if (fsp->cdb_status == 0) {
1811                         /*
1812                          * good I/O status
1813                          */
1814                         sc_cmd->result = DID_OK << 16;
1815                         if (fsp->scsi_resid)
1816                                 CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1817                 } else if (fsp->cdb_status == QUEUE_FULL) {
1818                         struct scsi_device *tmp_sdev;
1819                         struct scsi_device *sdev = sc_cmd->device;
1820
1821                         shost_for_each_device(tmp_sdev, sdev->host) {
1822                                 if (tmp_sdev->id != sdev->id)
1823                                         continue;
1824
1825                                 if (tmp_sdev->queue_depth > 1) {
1826                                         scsi_track_queue_full(tmp_sdev,
1827                                                               tmp_sdev->
1828                                                               queue_depth - 1);
1829                                 }
1830                         }
1831                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1832                 } else {
1833                         /*
1834                          * transport level I/O was ok but scsi
1835                          * has non zero status
1836                          */
1837                         sc_cmd->result = (DID_OK << 16) | fsp->cdb_status;
1838                 }
1839                 break;
1840         case FC_ERROR:
1841                 sc_cmd->result = DID_ERROR << 16;
1842                 break;
1843         case FC_DATA_UNDRUN:
1844                 if ((fsp->cdb_status == 0) && !(fsp->req_flags & FC_SRB_READ)) {
1845                         /*
1846                          * scsi status is good but transport level
1847                          * underrun.
1848                          */
1849                         sc_cmd->result = DID_OK << 16;
1850                 } else {
1851                         /*
1852                          * scsi got underrun, this is an error
1853                          */
1854                         CMD_RESID_LEN(sc_cmd) = fsp->scsi_resid;
1855                         sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1856                 }
1857                 break;
1858         case FC_DATA_OVRRUN:
1859                 /*
1860                  * overrun is an error
1861                  */
1862                 sc_cmd->result = (DID_ERROR << 16) | fsp->cdb_status;
1863                 break;
1864         case FC_CMD_ABORTED:
1865                 sc_cmd->result = (DID_ERROR << 16) | fsp->io_status;
1866                 break;
1867         case FC_CMD_TIME_OUT:
1868                 sc_cmd->result = (DID_BUS_BUSY << 16) | fsp->io_status;
1869                 break;
1870         case FC_CMD_RESET:
1871                 sc_cmd->result = (DID_RESET << 16);
1872                 break;
1873         case FC_HRD_ERROR:
1874                 sc_cmd->result = (DID_NO_CONNECT << 16);
1875                 break;
1876         default:
1877                 sc_cmd->result = (DID_ERROR << 16);
1878                 break;
1879         }
1880
1881         list_del(&fsp->list);
1882         sc_cmd->SCp.ptr = NULL;
1883         sc_cmd->scsi_done(sc_cmd);
1884         spin_unlock_irqrestore(lp->host->host_lock, flags);
1885
1886         /* release ref from initial allocation in queue command */
1887         fc_fcp_pkt_release(fsp);
1888 }
1889
1890 /**
1891  * fc_fcp_complete() - complete processing of a fcp packet
1892  * @fsp:        fcp packet
1893  *
1894  * This function may sleep if a fsp timer is pending.
1895  * The host lock must not be held by caller.
1896  */
1897 void fc_fcp_complete(struct fc_fcp_pkt *fsp)
1898 {
1899         if (fc_fcp_lock_pkt(fsp))
1900                 return;
1901
1902         fc_fcp_complete_locked(fsp);
1903         fc_fcp_unlock_pkt(fsp);
1904 }
1905 EXPORT_SYMBOL(fc_fcp_complete);
1906
1907 /**
1908  * fc_eh_abort() - Abort a command
1909  * @sc_cmd:     scsi command to abort
1910  *
1911  * From scsi host template.
1912  * send ABTS to the target device  and wait for the response
1913  * sc_cmd is the pointer to the command to be aborted.
1914  */
1915 int fc_eh_abort(struct scsi_cmnd *sc_cmd)
1916 {
1917         struct fc_fcp_pkt *fsp;
1918         struct fc_lport *lp;
1919         int rc = FAILED;
1920         unsigned long flags;
1921
1922         lp = shost_priv(sc_cmd->device->host);
1923         if (lp->state != LPORT_ST_READY)
1924                 return rc;
1925         else if (!lp->link_up)
1926                 return rc;
1927
1928         spin_lock_irqsave(lp->host->host_lock, flags);
1929         fsp = CMD_SP(sc_cmd);
1930         if (!fsp) {
1931                 /* command completed while scsi eh was setting up */
1932                 spin_unlock_irqrestore(lp->host->host_lock, flags);
1933                 return SUCCESS;
1934         }
1935         /* grab a ref so the fsp and sc_cmd cannot be relased from under us */
1936         fc_fcp_pkt_hold(fsp);
1937         spin_unlock_irqrestore(lp->host->host_lock, flags);
1938
1939         if (fc_fcp_lock_pkt(fsp)) {
1940                 /* completed while we were waiting for timer to be deleted */
1941                 rc = SUCCESS;
1942                 goto release_pkt;
1943         }
1944
1945         rc = fc_fcp_pkt_abort(lp, fsp);
1946         fc_fcp_unlock_pkt(fsp);
1947
1948 release_pkt:
1949         fc_fcp_pkt_release(fsp);
1950         return rc;
1951 }
1952 EXPORT_SYMBOL(fc_eh_abort);
1953
1954 /**
1955  * fc_eh_device_reset() Reset a single LUN
1956  * @sc_cmd:     scsi command
1957  *
1958  * Set from scsi host template to send tm cmd to the target and wait for the
1959  * response.
1960  */
1961 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd)
1962 {
1963         struct fc_lport *lp;
1964         struct fc_fcp_pkt *fsp;
1965         struct fc_rport *rport = starget_to_rport(scsi_target(sc_cmd->device));
1966         int rc = FAILED;
1967         struct fc_rport_libfc_priv *rp;
1968         int rval;
1969
1970         rval = fc_remote_port_chkready(rport);
1971         if (rval)
1972                 goto out;
1973
1974         rp = rport->dd_data;
1975         lp = shost_priv(sc_cmd->device->host);
1976
1977         if (lp->state != LPORT_ST_READY)
1978                 return rc;
1979
1980         FC_SCSI_DBG(lp, "Resetting rport (%6x)\n", rport->port_id);
1981
1982         fsp = fc_fcp_pkt_alloc(lp, GFP_NOIO);
1983         if (fsp == NULL) {
1984                 printk(KERN_WARNING "libfc: could not allocate scsi_pkt\n");
1985                 sc_cmd->result = DID_NO_CONNECT << 16;
1986                 goto out;
1987         }
1988
1989         /*
1990          * Build the libfc request pkt. Do not set the scsi cmnd, because
1991          * the sc passed in is not setup for execution like when sent
1992          * through the queuecommand callout.
1993          */
1994         fsp->lp = lp;           /* save the softc ptr */
1995         fsp->rport = rport;     /* set the remote port ptr */
1996
1997         /*
1998          * flush outstanding commands
1999          */
2000         rc = fc_lun_reset(lp, fsp, scmd_id(sc_cmd), sc_cmd->device->lun);
2001         fsp->state = FC_SRB_FREE;
2002         fc_fcp_pkt_release(fsp);
2003
2004 out:
2005         return rc;
2006 }
2007 EXPORT_SYMBOL(fc_eh_device_reset);
2008
2009 /**
2010  * fc_eh_host_reset() - The reset function will reset the ports on the host.
2011  * @sc_cmd:     scsi command
2012  */
2013 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd)
2014 {
2015         struct Scsi_Host *shost = sc_cmd->device->host;
2016         struct fc_lport *lp = shost_priv(shost);
2017         unsigned long wait_tmo;
2018
2019         FC_SCSI_DBG(lp, "Resetting host\n");
2020
2021         lp->tt.lport_reset(lp);
2022         wait_tmo = jiffies + FC_HOST_RESET_TIMEOUT;
2023         while (!fc_fcp_lport_queue_ready(lp) && time_before(jiffies, wait_tmo))
2024                 msleep(1000);
2025
2026         if (fc_fcp_lport_queue_ready(lp)) {
2027                 shost_printk(KERN_INFO, shost, "libfc: Host reset succeeded "
2028                              "on port (%6x)\n", fc_host_port_id(lp->host));
2029                 return SUCCESS;
2030         } else {
2031                 shost_printk(KERN_INFO, shost, "libfc: Host reset failed, "
2032                              "port (%6x) is not ready.\n",
2033                              fc_host_port_id(lp->host));
2034                 return FAILED;
2035         }
2036 }
2037 EXPORT_SYMBOL(fc_eh_host_reset);
2038
2039 /**
2040  * fc_slave_alloc() - configure queue depth
2041  * @sdev:       scsi device
2042  *
2043  * Configures queue depth based on host's cmd_per_len. If not set
2044  * then we use the libfc default.
2045  */
2046 int fc_slave_alloc(struct scsi_device *sdev)
2047 {
2048         struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
2049         int queue_depth;
2050
2051         if (!rport || fc_remote_port_chkready(rport))
2052                 return -ENXIO;
2053
2054         if (sdev->tagged_supported) {
2055                 if (sdev->host->hostt->cmd_per_lun)
2056                         queue_depth = sdev->host->hostt->cmd_per_lun;
2057                 else
2058                         queue_depth = FC_FCP_DFLT_QUEUE_DEPTH;
2059                 scsi_activate_tcq(sdev, queue_depth);
2060         }
2061         return 0;
2062 }
2063 EXPORT_SYMBOL(fc_slave_alloc);
2064
2065 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth)
2066 {
2067         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
2068         return sdev->queue_depth;
2069 }
2070 EXPORT_SYMBOL(fc_change_queue_depth);
2071
2072 int fc_change_queue_type(struct scsi_device *sdev, int tag_type)
2073 {
2074         if (sdev->tagged_supported) {
2075                 scsi_set_tag_type(sdev, tag_type);
2076                 if (tag_type)
2077                         scsi_activate_tcq(sdev, sdev->queue_depth);
2078                 else
2079                         scsi_deactivate_tcq(sdev, sdev->queue_depth);
2080         } else
2081                 tag_type = 0;
2082
2083         return tag_type;
2084 }
2085 EXPORT_SYMBOL(fc_change_queue_type);
2086
2087 void fc_fcp_destroy(struct fc_lport *lp)
2088 {
2089         struct fc_fcp_internal *si = fc_get_scsi_internal(lp);
2090
2091         if (!list_empty(&si->scsi_pkt_queue))
2092                 printk(KERN_ERR "libfc: Leaked SCSI packets when destroying "
2093                        "port (%6x)\n", fc_host_port_id(lp->host));
2094
2095         mempool_destroy(si->scsi_pkt_pool);
2096         kfree(si);
2097         lp->scsi_priv = NULL;
2098 }
2099 EXPORT_SYMBOL(fc_fcp_destroy);
2100
2101 int fc_fcp_init(struct fc_lport *lp)
2102 {
2103         int rc;
2104         struct fc_fcp_internal *si;
2105
2106         if (!lp->tt.fcp_cmd_send)
2107                 lp->tt.fcp_cmd_send = fc_fcp_cmd_send;
2108
2109         if (!lp->tt.fcp_cleanup)
2110                 lp->tt.fcp_cleanup = fc_fcp_cleanup;
2111
2112         if (!lp->tt.fcp_abort_io)
2113                 lp->tt.fcp_abort_io = fc_fcp_abort_io;
2114
2115         si = kzalloc(sizeof(struct fc_fcp_internal), GFP_KERNEL);
2116         if (!si)
2117                 return -ENOMEM;
2118         lp->scsi_priv = si;
2119         INIT_LIST_HEAD(&si->scsi_pkt_queue);
2120
2121         si->scsi_pkt_pool = mempool_create_slab_pool(2, scsi_pkt_cachep);
2122         if (!si->scsi_pkt_pool) {
2123                 rc = -ENOMEM;
2124                 goto free_internal;
2125         }
2126         return 0;
2127
2128 free_internal:
2129         kfree(si);
2130         return rc;
2131 }
2132 EXPORT_SYMBOL(fc_fcp_init);
2133
2134 static int __init libfc_init(void)
2135 {
2136         int rc;
2137
2138         scsi_pkt_cachep = kmem_cache_create("libfc_fcp_pkt",
2139                                             sizeof(struct fc_fcp_pkt),
2140                                             0, SLAB_HWCACHE_ALIGN, NULL);
2141         if (scsi_pkt_cachep == NULL) {
2142                 printk(KERN_ERR "libfc: Unable to allocate SRB cache, "
2143                        "module load failed!");
2144                 return -ENOMEM;
2145         }
2146
2147         rc = fc_setup_exch_mgr();
2148         if (rc)
2149                 goto destroy_pkt_cache;
2150
2151         rc = fc_setup_rport();
2152         if (rc)
2153                 goto destroy_em;
2154
2155         return rc;
2156 destroy_em:
2157         fc_destroy_exch_mgr();
2158 destroy_pkt_cache:
2159         kmem_cache_destroy(scsi_pkt_cachep);
2160         return rc;
2161 }
2162
2163 static void __exit libfc_exit(void)
2164 {
2165         kmem_cache_destroy(scsi_pkt_cachep);
2166         fc_destroy_exch_mgr();
2167         fc_destroy_rport();
2168 }
2169
2170 module_init(libfc_init);
2171 module_exit(libfc_exit);