drivers/usb/storage/uas.c

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