drivers/usb/storage/uas.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * USB Attached SCSI
   4  * Note that this is not the same as the USB Mass Storage driver
   5  *
   6  * Copyright Hans de Goede <hdegoede@redhat.com> for Red Hat, Inc. 2013 - 2016
   7  * Copyright Matthew Wilcox for Intel Corp, 2010
   8  * Copyright Sarah Sharp for Intel Corp, 2010
   9  */
  10
  11 #include <linux/blkdev.h>
  12 #include <linux/slab.h>
  13 #include <linux/types.h>
  14 #include <linux/module.h>
  15 #include <linux/usb.h>
  16 #include <linux/usb_usual.h>
  17 #include <linux/usb/hcd.h>
  18 #include <linux/usb/storage.h>
  19 #include <linux/usb/uas.h>
  20
  21 #include <scsi/scsi.h>
  22 #include <scsi/scsi_eh.h>
  23 #include <scsi/scsi_dbg.h>
  24 #include <scsi/scsi_cmnd.h>
  25 #include <scsi/scsi_device.h>
  26 #include <scsi/scsi_host.h>
  27 #include <scsi/scsi_tcq.h>
  28
  29 #include "uas-detect.h"
  30 #include "scsiglue.h"
  31
  32 #define MAX_CMNDS 256
  33
  34 struct uas_dev_info {
  35         struct usb_interface *intf;
  36         struct usb_device *udev;
  37         struct usb_anchor cmd_urbs;
  38         struct usb_anchor sense_urbs;
  39         struct usb_anchor data_urbs;
  40         unsigned long flags;
  41         int qdepth, resetting;
  42         unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
  43         unsigned use_streams:1;
  44         unsigned shutdown:1;
  45         struct scsi_cmnd *cmnd[MAX_CMNDS];
  46         spinlock_t lock;
  47         struct work_struct work;
  48         struct work_struct scan_work;      /* for async scanning */
  49 };
  50
  51 enum {
  52         SUBMIT_STATUS_URB       = BIT(1),
  53         ALLOC_DATA_IN_URB       = BIT(2),
  54         SUBMIT_DATA_IN_URB      = BIT(3),
  55         ALLOC_DATA_OUT_URB      = BIT(4),
  56         SUBMIT_DATA_OUT_URB     = BIT(5),
  57         ALLOC_CMD_URB           = BIT(6),
  58         SUBMIT_CMD_URB          = BIT(7),
  59         COMMAND_INFLIGHT        = BIT(8),
  60         DATA_IN_URB_INFLIGHT    = BIT(9),
  61         DATA_OUT_URB_INFLIGHT   = BIT(10),
  62         COMMAND_ABORTED         = BIT(11),
  63         IS_IN_WORK_LIST         = BIT(12),
  64 };
  65
  66 /* Overrides scsi_pointer */
  67 struct uas_cmd_info {
  68         unsigned int state;
  69         unsigned int uas_tag;
  70         struct urb *cmd_urb;
  71         struct urb *data_in_urb;
  72         struct urb *data_out_urb;
  73 };
  74
  75 /* I hate forward declarations, but I actually have a loop */
  76 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
  77                                 struct uas_dev_info *devinfo);
  78 static void uas_do_work(struct work_struct *work);
  79 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
  80 static void uas_free_streams(struct uas_dev_info *devinfo);
  81 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
  82                                 int status);
  83
  84 /*
  85  * This driver needs its own workqueue, as we need to control memory allocation.
  86  *
  87  * In the course of error handling and power management uas_wait_for_pending_cmnds()
  88  * needs to flush pending work items. In these contexts we cannot allocate memory
  89  * by doing block IO as we would deadlock. For the same reason we cannot wait
  90  * for anything allocating memory not heeding these constraints.
  91  *
  92  * So we have to control all work items that can be on the workqueue we flush.
  93  * Hence we cannot share a queue and need our own.
  94  */
  95 static struct workqueue_struct *workqueue;
  96
  97 static void uas_do_work(struct work_struct *work)
  98 {
  99         struct uas_dev_info *devinfo =
 100                 container_of(work, struct uas_dev_info, work);
 101         struct uas_cmd_info *cmdinfo;
 102         struct scsi_cmnd *cmnd;
 103         unsigned long flags;
 104         int i, err;
 105
 106         spin_lock_irqsave(&devinfo->lock, flags);
 107
 108         if (devinfo->resetting)
 109                 goto out;
 110
 111         for (i = 0; i < devinfo->qdepth; i++) {
 112                 if (!devinfo->cmnd[i])
 113                         continue;
 114
 115                 cmnd = devinfo->cmnd[i];
 116                 cmdinfo = (void *)&cmnd->SCp;
 117
 118                 if (!(cmdinfo->state & IS_IN_WORK_LIST))
 119                         continue;
 120
 121                 err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
 122                 if (!err)
 123                         cmdinfo->state &= ~IS_IN_WORK_LIST;
 124                 else
 125                         queue_work(workqueue, &devinfo->work);
 126         }
 127 out:
 128         spin_unlock_irqrestore(&devinfo->lock, flags);
 129 }
 130
 131 static void uas_scan_work(struct work_struct *work)
 132 {
 133         struct uas_dev_info *devinfo =
 134                 container_of(work, struct uas_dev_info, scan_work);
 135         struct Scsi_Host *shost = usb_get_intfdata(devinfo->intf);
 136
 137         dev_dbg(&devinfo->intf->dev, "starting scan\n");
 138         scsi_scan_host(shost);
 139         dev_dbg(&devinfo->intf->dev, "scan complete\n");
 140 }
 141
 142 static void uas_add_work(struct uas_cmd_info *cmdinfo)
 143 {
 144         struct scsi_pointer *scp = (void *)cmdinfo;
 145         struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
 146         struct uas_dev_info *devinfo = cmnd->device->hostdata;
 147
 148         lockdep_assert_held(&devinfo->lock);
 149         cmdinfo->state |= IS_IN_WORK_LIST;
 150         queue_work(workqueue, &devinfo->work);
 151 }
 152
 153 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
 154 {
 155         struct uas_cmd_info *cmdinfo;
 156         struct scsi_cmnd *cmnd;
 157         unsigned long flags;
 158         int i, err;
 159
 160         spin_lock_irqsave(&devinfo->lock, flags);
 161         for (i = 0; i < devinfo->qdepth; i++) {
 162                 if (!devinfo->cmnd[i])
 163                         continue;
 164
 165                 cmnd = devinfo->cmnd[i];
 166                 cmdinfo = (void *)&cmnd->SCp;
 167                 uas_log_cmd_state(cmnd, __func__, 0);
 168                 /* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
 169                 cmdinfo->state &= ~COMMAND_INFLIGHT;
 170                 cmnd->result = result << 16;
 171                 err = uas_try_complete(cmnd, __func__);
 172                 WARN_ON(err != 0);
 173         }
 174         spin_unlock_irqrestore(&devinfo->lock, flags);
 175 }
 176
 177 static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
 178 {
 179         struct sense_iu *sense_iu = urb->transfer_buffer;
 180         struct scsi_device *sdev = cmnd->device;
 181
 182         if (urb->actual_length > 16) {
 183                 unsigned len = be16_to_cpup(&sense_iu->len);
 184                 if (len + 16 != urb->actual_length) {
 185                         int newlen = min(len + 16, urb->actual_length) - 16;
 186                         if (newlen < 0)
 187                                 newlen = 0;
 188                         sdev_printk(KERN_INFO, sdev, "%s: urb length %d "
 189                                 "disagrees with IU sense data length %d, "
 190                                 "using %d bytes of sense data\n", __func__,
 191                                         urb->actual_length, len, newlen);
 192                         len = newlen;
 193                 }
 194                 memcpy(cmnd->sense_buffer, sense_iu->sense, len);
 195         }
 196
 197         cmnd->result = sense_iu->status;
 198 }
 199
 200 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
 201                               int status)
 202 {
 203         struct uas_cmd_info *ci = (void *)&cmnd->SCp;
 204         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 205
 206         if (status == -ENODEV) /* too late */
 207                 return;
 208
 209         scmd_printk(KERN_INFO, cmnd,
 210                     "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
 211                     prefix, status, cmdinfo->uas_tag,
 212                     (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
 213                     (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
 214                     (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
 215                     (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
 216                     (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
 217                     (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
 218                     (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
 219                     (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
 220                     (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
 221                     (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
 222                     (ci->state & COMMAND_ABORTED)       ? " abort" : "",
 223                     (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
 224         scsi_print_command(cmnd);
 225 }
 226
 227 static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
 228 {
 229         struct uas_cmd_info *cmdinfo;
 230
 231         if (!cmnd)
 232                 return;
 233
 234         cmdinfo = (void *)&cmnd->SCp;
 235
 236         if (cmdinfo->state & SUBMIT_CMD_URB)
 237                 usb_free_urb(cmdinfo->cmd_urb);
 238
 239         /* data urbs may have never gotten their submit flag set */
 240         if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
 241                 usb_free_urb(cmdinfo->data_in_urb);
 242         if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
 243                 usb_free_urb(cmdinfo->data_out_urb);
 244 }
 245
 246 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
 247 {
 248         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 249         struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 250
 251         lockdep_assert_held(&devinfo->lock);
 252         if (cmdinfo->state & (COMMAND_INFLIGHT |
 253                               DATA_IN_URB_INFLIGHT |
 254                               DATA_OUT_URB_INFLIGHT |
 255                               COMMAND_ABORTED))
 256                 return -EBUSY;
 257         devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
 258         uas_free_unsubmitted_urbs(cmnd);
 259         cmnd->scsi_done(cmnd);
 260         return 0;
 261 }
 262
 263 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
 264                           unsigned direction)
 265 {
 266         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 267         int err;
 268
 269         cmdinfo->state |= direction | SUBMIT_STATUS_URB;
 270         err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
 271         if (err) {
 272                 uas_add_work(cmdinfo);
 273         }
 274 }
 275
 276 static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
 277 {
 278         u8 response_code = riu->response_code;
 279
 280         switch (response_code) {
 281         case RC_INCORRECT_LUN:
 282                 cmnd->result = DID_BAD_TARGET << 16;
 283                 break;
 284         case RC_TMF_SUCCEEDED:
 285                 cmnd->result = DID_OK << 16;
 286                 break;
 287         case RC_TMF_NOT_SUPPORTED:
 288                 cmnd->result = DID_TARGET_FAILURE << 16;
 289                 break;
 290         default:
 291                 uas_log_cmd_state(cmnd, "response iu", response_code);
 292                 cmnd->result = DID_ERROR << 16;
 293                 break;
 294         }
 295
 296         return response_code == RC_TMF_SUCCEEDED;
 297 }
 298
 299 static void uas_stat_cmplt(struct urb *urb)
 300 {
 301         struct iu *iu = urb->transfer_buffer;
 302         struct Scsi_Host *shost = urb->context;
 303         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
 304         struct urb *data_in_urb = NULL;
 305         struct urb *data_out_urb = NULL;
 306         struct scsi_cmnd *cmnd;
 307         struct uas_cmd_info *cmdinfo;
 308         unsigned long flags;
 309         unsigned int idx;
 310         int status = urb->status;
 311         bool success;
 312
 313         spin_lock_irqsave(&devinfo->lock, flags);
 314
 315         if (devinfo->resetting)
 316                 goto out;
 317
 318         if (status) {
 319                 if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 320                         dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
 321                 goto out;
 322         }
 323
 324         idx = be16_to_cpup(&iu->tag) - 1;
 325         if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
 326                 dev_err(&urb->dev->dev,
 327                         "stat urb: no pending cmd for uas-tag %d\n", idx + 1);
 328                 goto out;
 329         }
 330
 331         cmnd = devinfo->cmnd[idx];
 332         cmdinfo = (void *)&cmnd->SCp;
 333
 334         if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
 335                 uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
 336                 goto out;
 337         }
 338
 339         switch (iu->iu_id) {
 340         case IU_ID_STATUS:
 341                 uas_sense(urb, cmnd);
 342                 if (cmnd->result != 0) {
 343                         /* cancel data transfers on error */
 344                         data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 345                         data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 346                 }
 347                 cmdinfo->state &= ~COMMAND_INFLIGHT;
 348                 uas_try_complete(cmnd, __func__);
 349                 break;
 350         case IU_ID_READ_READY:
 351                 if (!cmdinfo->data_in_urb ||
 352                                 (cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
 353                         uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
 354                         break;
 355                 }
 356                 uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
 357                 break;
 358         case IU_ID_WRITE_READY:
 359                 if (!cmdinfo->data_out_urb ||
 360                                 (cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
 361                         uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
 362                         break;
 363                 }
 364                 uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
 365                 break;
 366         case IU_ID_RESPONSE:
 367                 cmdinfo->state &= ~COMMAND_INFLIGHT;
 368                 success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
 369                 if (!success) {
 370                         /* Error, cancel data transfers */
 371                         data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 372                         data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 373                 }
 374                 uas_try_complete(cmnd, __func__);
 375                 break;
 376         default:
 377                 uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
 378         }
 379 out:
 380         usb_free_urb(urb);
 381         spin_unlock_irqrestore(&devinfo->lock, flags);
 382
 383         /* Unlinking of data urbs must be done without holding the lock */
 384         if (data_in_urb) {
 385                 usb_unlink_urb(data_in_urb);
 386                 usb_put_urb(data_in_urb);
 387         }
 388         if (data_out_urb) {
 389                 usb_unlink_urb(data_out_urb);
 390                 usb_put_urb(data_out_urb);
 391         }
 392 }
 393
 394 static void uas_data_cmplt(struct urb *urb)
 395 {
 396         struct scsi_cmnd *cmnd = urb->context;
 397         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 398         struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 399         struct scsi_data_buffer *sdb = NULL;
 400         unsigned long flags;
 401         int status = urb->status;
 402
 403         spin_lock_irqsave(&devinfo->lock, flags);
 404
 405         if (cmdinfo->data_in_urb == urb) {
 406                 sdb = scsi_in(cmnd);
 407                 cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
 408                 cmdinfo->data_in_urb = NULL;
 409         } else if (cmdinfo->data_out_urb == urb) {
 410                 sdb = scsi_out(cmnd);
 411                 cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
 412                 cmdinfo->data_out_urb = NULL;
 413         }
 414         if (sdb == NULL) {
 415                 WARN_ON_ONCE(1);
 416                 goto out;
 417         }
 418
 419         if (devinfo->resetting)
 420                 goto out;
 421
 422         /* Data urbs should not complete before the cmd urb is submitted */
 423         if (cmdinfo->state & SUBMIT_CMD_URB) {
 424                 uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
 425                 goto out;
 426         }
 427
 428         if (status) {
 429                 if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 430                         uas_log_cmd_state(cmnd, "data cmplt err", status);
 431                 /* error: no data transfered */
 432                 sdb->resid = sdb->length;
 433         } else {
 434                 sdb->resid = sdb->length - urb->actual_length;
 435         }
 436         uas_try_complete(cmnd, __func__);
 437 out:
 438         usb_free_urb(urb);
 439         spin_unlock_irqrestore(&devinfo->lock, flags);
 440 }
 441
 442 static void uas_cmd_cmplt(struct urb *urb)
 443 {
 444         if (urb->status)
 445                 dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
 446
 447         usb_free_urb(urb);
 448 }
 449
 450 static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 451                                       struct scsi_cmnd *cmnd,
 452                                       enum dma_data_direction dir)
 453 {
 454         struct usb_device *udev = devinfo->udev;
 455         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 456         struct urb *urb = usb_alloc_urb(0, gfp);
 457         struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
 458                 ? scsi_in(cmnd) : scsi_out(cmnd);
 459         unsigned int pipe = (dir == DMA_FROM_DEVICE)
 460                 ? devinfo->data_in_pipe : devinfo->data_out_pipe;
 461
 462         if (!urb)
 463                 goto out;
 464         usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
 465                           uas_data_cmplt, cmnd);
 466         if (devinfo->use_streams)
 467                 urb->stream_id = cmdinfo->uas_tag;
 468         urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
 469         urb->sg = sdb->table.sgl;
 470  out:
 471         return urb;
 472 }
 473
 474 static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 475                                        struct scsi_cmnd *cmnd)
 476 {
 477         struct usb_device *udev = devinfo->udev;
 478         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 479         struct urb *urb = usb_alloc_urb(0, gfp);
 480         struct sense_iu *iu;
 481
 482         if (!urb)
 483                 goto out;
 484
 485         iu = kzalloc(sizeof(*iu), gfp);
 486         if (!iu)
 487                 goto free;
 488
 489         usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
 490                           uas_stat_cmplt, cmnd->device->host);
 491         if (devinfo->use_streams)
 492                 urb->stream_id = cmdinfo->uas_tag;
 493         urb->transfer_flags |= URB_FREE_BUFFER;
 494  out:
 495         return urb;
 496  free:
 497         usb_free_urb(urb);
 498         return NULL;
 499 }
 500
 501 static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 502                                         struct scsi_cmnd *cmnd)
 503 {
 504         struct usb_device *udev = devinfo->udev;
 505         struct scsi_device *sdev = cmnd->device;
 506         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 507         struct urb *urb = usb_alloc_urb(0, gfp);
 508         struct command_iu *iu;
 509         int len;
 510
 511         if (!urb)
 512                 goto out;
 513
 514         len = cmnd->cmd_len - 16;
 515         if (len < 0)
 516                 len = 0;
 517         len = ALIGN(len, 4);
 518         iu = kzalloc(sizeof(*iu) + len, gfp);
 519         if (!iu)
 520                 goto free;
 521
 522         iu->iu_id = IU_ID_COMMAND;
 523         iu->tag = cpu_to_be16(cmdinfo->uas_tag);
 524         iu->prio_attr = UAS_SIMPLE_TAG;
 525         iu->len = len;
 526         int_to_scsilun(sdev->lun, &iu->lun);
 527         memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
 528
 529         usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
 530                                                         uas_cmd_cmplt, NULL);
 531         urb->transfer_flags |= URB_FREE_BUFFER;
 532  out:
 533         return urb;
 534  free:
 535         usb_free_urb(urb);
 536         return NULL;
 537 }
 538
 539 /*
 540  * Why should I request the Status IU before sending the Command IU?  Spec
 541  * says to, but also says the device may receive them in any order.  Seems
 542  * daft to me.
 543  */
 544
 545 static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
 546 {
 547         struct uas_dev_info *devinfo = cmnd->device->hostdata;
 548         struct urb *urb;
 549         int err;
 550
 551         urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
 552         if (!urb)
 553                 return NULL;
 554         usb_anchor_urb(urb, &devinfo->sense_urbs);
 555         err = usb_submit_urb(urb, gfp);
 556         if (err) {
 557                 usb_unanchor_urb(urb);
 558                 uas_log_cmd_state(cmnd, "sense submit err", err);
 559                 usb_free_urb(urb);
 560                 return NULL;
 561         }
 562         return urb;
 563 }
 564
 565 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 566                            struct uas_dev_info *devinfo)
 567 {
 568         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 569         struct urb *urb;
 570         int err;
 571
 572         lockdep_assert_held(&devinfo->lock);
 573         if (cmdinfo->state & SUBMIT_STATUS_URB) {
 574                 urb = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
 575                 if (!urb)
 576                         return SCSI_MLQUEUE_DEVICE_BUSY;
 577                 cmdinfo->state &= ~SUBMIT_STATUS_URB;
 578         }
 579
 580         if (cmdinfo->state & ALLOC_DATA_IN_URB) {
 581                 cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 582                                                         cmnd, DMA_FROM_DEVICE);
 583                 if (!cmdinfo->data_in_urb)
 584                         return SCSI_MLQUEUE_DEVICE_BUSY;
 585                 cmdinfo->state &= ~ALLOC_DATA_IN_URB;
 586         }
 587
 588         if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
 589                 usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
 590                 err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
 591                 if (err) {
 592                         usb_unanchor_urb(cmdinfo->data_in_urb);
 593                         uas_log_cmd_state(cmnd, "data in submit err", err);
 594                         return SCSI_MLQUEUE_DEVICE_BUSY;
 595                 }
 596                 cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
 597                 cmdinfo->state |= DATA_IN_URB_INFLIGHT;
 598         }
 599
 600         if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
 601                 cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 602                                                         cmnd, DMA_TO_DEVICE);
 603                 if (!cmdinfo->data_out_urb)
 604                         return SCSI_MLQUEUE_DEVICE_BUSY;
 605                 cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
 606         }
 607
 608         if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
 609                 usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
 610                 err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
 611                 if (err) {
 612                         usb_unanchor_urb(cmdinfo->data_out_urb);
 613                         uas_log_cmd_state(cmnd, "data out submit err", err);
 614                         return SCSI_MLQUEUE_DEVICE_BUSY;
 615                 }
 616                 cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
 617                 cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
 618         }
 619
 620         if (cmdinfo->state & ALLOC_CMD_URB) {
 621                 cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
 622                 if (!cmdinfo->cmd_urb)
 623                         return SCSI_MLQUEUE_DEVICE_BUSY;
 624                 cmdinfo->state &= ~ALLOC_CMD_URB;
 625         }
 626
 627         if (cmdinfo->state & SUBMIT_CMD_URB) {
 628                 usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
 629                 err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
 630                 if (err) {
 631                         usb_unanchor_urb(cmdinfo->cmd_urb);
 632                         uas_log_cmd_state(cmnd, "cmd submit err", err);
 633                         return SCSI_MLQUEUE_DEVICE_BUSY;
 634                 }
 635                 cmdinfo->cmd_urb = NULL;
 636                 cmdinfo->state &= ~SUBMIT_CMD_URB;
 637                 cmdinfo->state |= COMMAND_INFLIGHT;
 638         }
 639
 640         return 0;
 641 }
 642
 643 static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 644                                         void (*done)(struct scsi_cmnd *))
 645 {
 646         struct scsi_device *sdev = cmnd->device;
 647         struct uas_dev_info *devinfo = sdev->hostdata;
 648         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 649         unsigned long flags;
 650         int idx, err;
 651
 652         BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
 653
 654         /* Re-check scsi_block_requests now that we've the host-lock */
 655         if (cmnd->device->host->host_self_blocked)
 656                 return SCSI_MLQUEUE_DEVICE_BUSY;
 657
 658         if ((devinfo->flags & US_FL_NO_ATA_1X) &&
 659                         (cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
 660                 memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
 661                        sizeof(usb_stor_sense_invalidCDB));
 662                 cmnd->result = SAM_STAT_CHECK_CONDITION;
 663                 cmnd->scsi_done(cmnd);
 664                 return 0;
 665         }
 666
 667         spin_lock_irqsave(&devinfo->lock, flags);
 668
 669         if (devinfo->resetting) {
 670                 cmnd->result = DID_ERROR << 16;
 671                 cmnd->scsi_done(cmnd);
 672                 goto zombie;
 673         }
 674
 675         /* Find a free uas-tag */
 676         for (idx = 0; idx < devinfo->qdepth; idx++) {
 677                 if (!devinfo->cmnd[idx])
 678                         break;
 679         }
 680         if (idx == devinfo->qdepth) {
 681                 spin_unlock_irqrestore(&devinfo->lock, flags);
 682                 return SCSI_MLQUEUE_DEVICE_BUSY;
 683         }
 684
 685         cmnd->scsi_done = done;
 686
 687         memset(cmdinfo, 0, sizeof(*cmdinfo));
 688         cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
 689         cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
 690
 691         switch (cmnd->sc_data_direction) {
 692         case DMA_FROM_DEVICE:
 693                 cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
 694                 break;
 695         case DMA_BIDIRECTIONAL:
 696                 cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
 697                 /* fall through */
 698         case DMA_TO_DEVICE:
 699                 cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
 700         case DMA_NONE:
 701                 break;
 702         }
 703
 704         if (!devinfo->use_streams)
 705                 cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
 706
 707         err = uas_submit_urbs(cmnd, devinfo);
 708         /*
 709          * in case of fatal errors the SCSI layer is peculiar
 710          * a command that has finished is a success for the purpose
 711          * of queueing, no matter how fatal the error
 712          */
 713         if (err == -ENODEV) {
 714                 cmnd->result = DID_ERROR << 16;
 715                 cmnd->scsi_done(cmnd);
 716                 goto zombie;
 717         }
 718         if (err) {
 719                 /* If we did nothing, give up now */
 720                 if (cmdinfo->state & SUBMIT_STATUS_URB) {
 721                         spin_unlock_irqrestore(&devinfo->lock, flags);
 722                         return SCSI_MLQUEUE_DEVICE_BUSY;
 723                 }
 724                 uas_add_work(cmdinfo);
 725         }
 726
 727         devinfo->cmnd[idx] = cmnd;
 728 zombie:
 729         spin_unlock_irqrestore(&devinfo->lock, flags);
 730         return 0;
 731 }
 732
 733 static DEF_SCSI_QCMD(uas_queuecommand)
 734
 735 /*
 736  * For now we do not support actually sending an abort to the device, so
 737  * this eh always fails. Still we must define it to make sure that we've
 738  * dropped all references to the cmnd in question once this function exits.
 739  */
 740 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
 741 {
 742         struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
 743         struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 744         struct urb *data_in_urb = NULL;
 745         struct urb *data_out_urb = NULL;
 746         unsigned long flags;
 747
 748         spin_lock_irqsave(&devinfo->lock, flags);
 749
 750         uas_log_cmd_state(cmnd, __func__, 0);
 751
 752         /* Ensure that try_complete does not call scsi_done */
 753         cmdinfo->state |= COMMAND_ABORTED;
 754
 755         /* Drop all refs to this cmnd, kill data urbs to break their ref */
 756         devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
 757         if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
 758                 data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 759         if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
 760                 data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 761
 762         uas_free_unsubmitted_urbs(cmnd);
 763
 764         spin_unlock_irqrestore(&devinfo->lock, flags);
 765
 766         if (data_in_urb) {
 767                 usb_kill_urb(data_in_urb);
 768                 usb_put_urb(data_in_urb);
 769         }
 770         if (data_out_urb) {
 771                 usb_kill_urb(data_out_urb);
 772                 usb_put_urb(data_out_urb);
 773         }
 774
 775         return FAILED;
 776 }
 777
 778 static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
 779 {
 780         struct scsi_device *sdev = cmnd->device;
 781         struct uas_dev_info *devinfo = sdev->hostdata;
 782         struct usb_device *udev = devinfo->udev;
 783         unsigned long flags;
 784         int err;
 785
 786         err = usb_lock_device_for_reset(udev, devinfo->intf);
 787         if (err) {
 788                 shost_printk(KERN_ERR, sdev->host,
 789                              "%s FAILED to get lock err %d\n", __func__, err);
 790                 return FAILED;
 791         }
 792
 793         shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
 794
 795         spin_lock_irqsave(&devinfo->lock, flags);
 796         devinfo->resetting = 1;
 797         spin_unlock_irqrestore(&devinfo->lock, flags);
 798
 799         usb_kill_anchored_urbs(&devinfo->cmd_urbs);
 800         usb_kill_anchored_urbs(&devinfo->sense_urbs);
 801         usb_kill_anchored_urbs(&devinfo->data_urbs);
 802         uas_zap_pending(devinfo, DID_RESET);
 803
 804         err = usb_reset_device(udev);
 805
 806         spin_lock_irqsave(&devinfo->lock, flags);
 807         devinfo->resetting = 0;
 808         spin_unlock_irqrestore(&devinfo->lock, flags);
 809
 810         usb_unlock_device(udev);
 811
 812         if (err) {
 813                 shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
 814                              __func__, err);
 815                 return FAILED;
 816         }
 817
 818         shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
 819         return SUCCESS;
 820 }
 821
 822 static int uas_target_alloc(struct scsi_target *starget)
 823 {
 824         struct uas_dev_info *devinfo = (struct uas_dev_info *)
 825                         dev_to_shost(starget->dev.parent)->hostdata;
 826
 827         if (devinfo->flags & US_FL_NO_REPORT_LUNS)
 828                 starget->no_report_luns = 1;
 829
 830         return 0;
 831 }
 832
 833 static int uas_slave_alloc(struct scsi_device *sdev)
 834 {
 835         struct uas_dev_info *devinfo =
 836                 (struct uas_dev_info *)sdev->host->hostdata;
 837
 838         sdev->hostdata = devinfo;
 839
 840         /*
 841          * The protocol has no requirements on alignment in the strict sense.
 842          * Controllers may or may not have alignment restrictions.
 843          * As this is not exported, we use an extremely conservative guess.
 844          */
 845         blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
 846
 847         if (devinfo->flags & US_FL_MAX_SECTORS_64)
 848                 blk_queue_max_hw_sectors(sdev->request_queue, 64);
 849         else if (devinfo->flags & US_FL_MAX_SECTORS_240)
 850                 blk_queue_max_hw_sectors(sdev->request_queue, 240);
 851
 852         return 0;
 853 }
 854
 855 static int uas_slave_configure(struct scsi_device *sdev)
 856 {
 857         struct uas_dev_info *devinfo = sdev->hostdata;
 858
 859         if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
 860                 sdev->no_report_opcodes = 1;
 861
 862         /* A few buggy USB-ATA bridges don't understand FUA */
 863         if (devinfo->flags & US_FL_BROKEN_FUA)
 864                 sdev->broken_fua = 1;
 865
 866         /* UAS also needs to support FL_ALWAYS_SYNC */
 867         if (devinfo->flags & US_FL_ALWAYS_SYNC) {
 868                 sdev->skip_ms_page_3f = 1;
 869                 sdev->skip_ms_page_8 = 1;
 870                 sdev->wce_default_on = 1;
 871         }
 872
 873         /* Some disks cannot handle READ_CAPACITY_16 */
 874         if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
 875                 sdev->no_read_capacity_16 = 1;
 876
 877         /* Some disks cannot handle WRITE_SAME */
 878         if (devinfo->flags & US_FL_NO_SAME)
 879                 sdev->no_write_same = 1;
 880         /*
 881          * Some disks return the total number of blocks in response
 882          * to READ CAPACITY rather than the highest block number.
 883          * If this device makes that mistake, tell the sd driver.
 884          */
 885         if (devinfo->flags & US_FL_FIX_CAPACITY)
 886                 sdev->fix_capacity = 1;
 887
 888         /*
 889          * in some cases we have to guess
 890          */
 891         if (devinfo->flags & US_FL_CAPACITY_HEURISTICS)
 892                 sdev->guess_capacity = 1;
 893
 894         /*
 895          * Some devices don't like MODE SENSE with page=0x3f,
 896          * which is the command used for checking if a device
 897          * is write-protected.  Now that we tell the sd driver
 898          * to do a 192-byte transfer with this command the
 899          * majority of devices work fine, but a few still can't
 900          * handle it.  The sd driver will simply assume those
 901          * devices are write-enabled.
 902          */
 903         if (devinfo->flags & US_FL_NO_WP_DETECT)
 904                 sdev->skip_ms_page_3f = 1;
 905
 906         scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
 907         return 0;
 908 }
 909
 910 static struct scsi_host_template uas_host_template = {
 911         .module = THIS_MODULE,
 912         .name = "uas",
 913         .queuecommand = uas_queuecommand,
 914         .target_alloc = uas_target_alloc,
 915         .slave_alloc = uas_slave_alloc,
 916         .slave_configure = uas_slave_configure,
 917         .eh_abort_handler = uas_eh_abort_handler,
 918         .eh_device_reset_handler = uas_eh_device_reset_handler,
 919         .this_id = -1,
 920         .sg_tablesize = SG_NONE,
 921         .skip_settle_delay = 1,
 922 };
 923
 924 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
 925                     vendorName, productName, useProtocol, useTransport, \
 926                     initFunction, flags) \
 927 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
 928         .driver_info = (flags) }
 929
 930 static struct usb_device_id uas_usb_ids[] = {
 931 #       include "unusual_uas.h"
 932         { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
 933         { USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
 934         { }
 935 };
 936 MODULE_DEVICE_TABLE(usb, uas_usb_ids);
 937
 938 #undef UNUSUAL_DEV
 939
 940 static int uas_switch_interface(struct usb_device *udev,
 941                                 struct usb_interface *intf)
 942 {
 943         struct usb_host_interface *alt;
 944
 945         alt = uas_find_uas_alt_setting(intf);
 946         if (!alt)
 947                 return -ENODEV;
 948
 949         return usb_set_interface(udev, alt->desc.bInterfaceNumber,
 950                         alt->desc.bAlternateSetting);
 951 }
 952
 953 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
 954 {
 955         struct usb_host_endpoint *eps[4] = { };
 956         struct usb_device *udev = devinfo->udev;
 957         int r;
 958
 959         r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
 960         if (r)
 961                 return r;
 962
 963         devinfo->cmd_pipe = usb_sndbulkpipe(udev,
 964                                             usb_endpoint_num(&eps[0]->desc));
 965         devinfo->status_pipe = usb_rcvbulkpipe(udev,
 966                                             usb_endpoint_num(&eps[1]->desc));
 967         devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
 968                                             usb_endpoint_num(&eps[2]->desc));
 969         devinfo->data_out_pipe = usb_sndbulkpipe(udev,
 970                                             usb_endpoint_num(&eps[3]->desc));
 971
 972         if (udev->speed < USB_SPEED_SUPER) {
 973                 devinfo->qdepth = 32;
 974                 devinfo->use_streams = 0;
 975         } else {
 976                 devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
 977                                                     3, MAX_CMNDS, GFP_NOIO);
 978                 if (devinfo->qdepth < 0)
 979                         return devinfo->qdepth;
 980                 devinfo->use_streams = 1;
 981         }
 982
 983         return 0;
 984 }
 985
 986 static void uas_free_streams(struct uas_dev_info *devinfo)
 987 {
 988         struct usb_device *udev = devinfo->udev;
 989         struct usb_host_endpoint *eps[3];
 990
 991         eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
 992         eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
 993         eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
 994         usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
 995 }
 996
 997 static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
 998 {
 999         int result = -ENOMEM;
1000         struct Scsi_Host *shost = NULL;
1001         struct uas_dev_info *devinfo;
1002         struct usb_device *udev = interface_to_usbdev(intf);
1003         unsigned long dev_flags;
1004
1005         if (!uas_use_uas_driver(intf, id, &dev_flags))
1006                 return -ENODEV;
1007
1008         if (uas_switch_interface(udev, intf))
1009                 return -ENODEV;
1010
1011         shost = scsi_host_alloc(&uas_host_template,
1012                                 sizeof(struct uas_dev_info));
1013         if (!shost)
1014                 goto set_alt0;
1015
1016         shost->max_cmd_len = 16 + 252;
1017         shost->max_id = 1;
1018         shost->max_lun = 256;
1019         shost->max_channel = 0;
1020         shost->sg_tablesize = udev->bus->sg_tablesize;
1021
1022         devinfo = (struct uas_dev_info *)shost->hostdata;
1023         devinfo->intf = intf;
1024         devinfo->udev = udev;
1025         devinfo->resetting = 0;
1026         devinfo->shutdown = 0;
1027         devinfo->flags = dev_flags;
1028         init_usb_anchor(&devinfo->cmd_urbs);
1029         init_usb_anchor(&devinfo->sense_urbs);
1030         init_usb_anchor(&devinfo->data_urbs);
1031         spin_lock_init(&devinfo->lock);
1032         INIT_WORK(&devinfo->work, uas_do_work);
1033         INIT_WORK(&devinfo->scan_work, uas_scan_work);
1034
1035         result = uas_configure_endpoints(devinfo);
1036         if (result)
1037                 goto set_alt0;
1038
1039         /*
1040          * 1 tag is reserved for untagged commands +
1041          * 1 tag to avoid off by one errors in some bridge firmwares
1042          */
1043         shost->can_queue = devinfo->qdepth - 2;
1044
1045         usb_set_intfdata(intf, shost);
1046         result = scsi_add_host(shost, &intf->dev);
1047         if (result)
1048                 goto free_streams;
1049
1050         /* Submit the delayed_work for SCSI-device scanning */
1051         schedule_work(&devinfo->scan_work);
1052
1053         return result;
1054
1055 free_streams:
1056         uas_free_streams(devinfo);
1057         usb_set_intfdata(intf, NULL);
1058 set_alt0:
1059         usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1060         if (shost)
1061                 scsi_host_put(shost);
1062         return result;
1063 }
1064
1065 static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
1066 {
1067         unsigned long flags;
1068         int i, r = 1;
1069
1070         spin_lock_irqsave(&devinfo->lock, flags);
1071
1072         for (i = 0; i < devinfo->qdepth; i++) {
1073                 if (devinfo->cmnd[i]) {
1074                         r = 0; /* Not empty */
1075                         break;
1076                 }
1077         }
1078
1079         spin_unlock_irqrestore(&devinfo->lock, flags);
1080
1081         return r;
1082 }
1083
1084 /*
1085  * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1086  * get empty while there still is more work to do due to sense-urbs completing
1087  * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1088  */
1089 static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1090 {
1091         unsigned long start_time;
1092         int r;
1093
1094         start_time = jiffies;
1095         do {
1096                 flush_work(&devinfo->work);
1097
1098                 r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1099                 if (r == 0)
1100                         return -ETIME;
1101
1102                 r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1103                 if (r == 0)
1104                         return -ETIME;
1105
1106                 if (time_after(jiffies, start_time + 5 * HZ))
1107                         return -ETIME;
1108         } while (!uas_cmnd_list_empty(devinfo));
1109
1110         return 0;
1111 }
1112
1113 static int uas_pre_reset(struct usb_interface *intf)
1114 {
1115         struct Scsi_Host *shost = usb_get_intfdata(intf);
1116         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1117         unsigned long flags;
1118
1119         if (devinfo->shutdown)
1120                 return 0;
1121
1122         /* Block new requests */
1123         spin_lock_irqsave(shost->host_lock, flags);
1124         scsi_block_requests(shost);
1125         spin_unlock_irqrestore(shost->host_lock, flags);
1126
1127         if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1128                 shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1129                 scsi_unblock_requests(shost);
1130                 return 1;
1131         }
1132
1133         uas_free_streams(devinfo);
1134
1135         return 0;
1136 }
1137
1138 static int uas_post_reset(struct usb_interface *intf)
1139 {
1140         struct Scsi_Host *shost = usb_get_intfdata(intf);
1141         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1142         unsigned long flags;
1143         int err;
1144
1145         if (devinfo->shutdown)
1146                 return 0;
1147
1148         err = uas_configure_endpoints(devinfo);
1149         if (err && err != -ENODEV)
1150                 shost_printk(KERN_ERR, shost,
1151                              "%s: alloc streams error %d after reset",
1152                              __func__, err);
1153
1154         /* we must unblock the host in every case lest we deadlock */
1155         spin_lock_irqsave(shost->host_lock, flags);
1156         scsi_report_bus_reset(shost, 0);
1157         spin_unlock_irqrestore(shost->host_lock, flags);
1158
1159         scsi_unblock_requests(shost);
1160
1161         return err ? 1 : 0;
1162 }
1163
1164 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1165 {
1166         struct Scsi_Host *shost = usb_get_intfdata(intf);
1167         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1168
1169         if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1170                 shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1171                 return -ETIME;
1172         }
1173
1174         return 0;
1175 }
1176
1177 static int uas_resume(struct usb_interface *intf)
1178 {
1179         return 0;
1180 }
1181
1182 static int uas_reset_resume(struct usb_interface *intf)
1183 {
1184         struct Scsi_Host *shost = usb_get_intfdata(intf);
1185         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1186         unsigned long flags;
1187         int err;
1188
1189         err = uas_configure_endpoints(devinfo);
1190         if (err) {
1191                 shost_printk(KERN_ERR, shost,
1192                              "%s: alloc streams error %d after reset",
1193                              __func__, err);
1194                 return -EIO;
1195         }
1196
1197         spin_lock_irqsave(shost->host_lock, flags);
1198         scsi_report_bus_reset(shost, 0);
1199         spin_unlock_irqrestore(shost->host_lock, flags);
1200
1201         return 0;
1202 }
1203
1204 static void uas_disconnect(struct usb_interface *intf)
1205 {
1206         struct Scsi_Host *shost = usb_get_intfdata(intf);
1207         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1208         unsigned long flags;
1209
1210         spin_lock_irqsave(&devinfo->lock, flags);
1211         devinfo->resetting = 1;
1212         spin_unlock_irqrestore(&devinfo->lock, flags);
1213
1214         cancel_work_sync(&devinfo->work);
1215         usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1216         usb_kill_anchored_urbs(&devinfo->sense_urbs);
1217         usb_kill_anchored_urbs(&devinfo->data_urbs);
1218         uas_zap_pending(devinfo, DID_NO_CONNECT);
1219
1220         /*
1221          * Prevent SCSI scanning (if it hasn't started yet)
1222          * or wait for the SCSI-scanning routine to stop.
1223          */
1224         cancel_work_sync(&devinfo->scan_work);
1225
1226         scsi_remove_host(shost);
1227         uas_free_streams(devinfo);
1228         scsi_host_put(shost);
1229 }
1230
1231 /*
1232  * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1233  * hang on reboot when the device is still in uas mode. Note the reset is
1234  * necessary as some devices won't revert to usb-storage mode without it.
1235  */
1236 static void uas_shutdown(struct device *dev)
1237 {
1238         struct usb_interface *intf = to_usb_interface(dev);
1239         struct usb_device *udev = interface_to_usbdev(intf);
1240         struct Scsi_Host *shost = usb_get_intfdata(intf);
1241         struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1242
1243         if (system_state != SYSTEM_RESTART)
1244                 return;
1245
1246         devinfo->shutdown = 1;
1247         uas_free_streams(devinfo);
1248         usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1249         usb_reset_device(udev);
1250 }
1251
1252 static struct usb_driver uas_driver = {
1253         .name = "uas",
1254         .probe = uas_probe,
1255         .disconnect = uas_disconnect,
1256         .pre_reset = uas_pre_reset,
1257         .post_reset = uas_post_reset,
1258         .suspend = uas_suspend,
1259         .resume = uas_resume,
1260         .reset_resume = uas_reset_resume,
1261         .drvwrap.driver.shutdown = uas_shutdown,
1262         .id_table = uas_usb_ids,
1263 };
1264
1265 static int __init uas_init(void)
1266 {
1267         int rv;
1268
1269         workqueue = alloc_workqueue("uas", WQ_MEM_RECLAIM, 0);
1270         if (!workqueue)
1271                 return -ENOMEM;
1272
1273         rv = usb_register(&uas_driver);
1274         if (rv) {
1275                 destroy_workqueue(workqueue);
1276                 return -ENOMEM;
1277         }
1278
1279         return 0;
1280 }
1281
1282 static void __exit uas_exit(void)
1283 {
1284         usb_deregister(&uas_driver);
1285         destroy_workqueue(workqueue);
1286 }
1287
1288 module_init(uas_init);
1289 module_exit(uas_exit);
1290
1291 MODULE_LICENSE("GPL");
1292 MODULE_AUTHOR(
1293         "Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");