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_devinfo.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
  35struct 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	u64 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
  52enum {
  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 */
  68struct 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 */
  77static int uas_submit_urbs(struct scsi_cmnd *cmnd,
  78				struct uas_dev_info *devinfo);
  79static void uas_do_work(struct work_struct *work);
  80static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller);
  81static void uas_free_streams(struct uas_dev_info *devinfo);
  82static 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 */
  96static struct workqueue_struct *workqueue;
  97
  98static 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 = scsi_cmd_priv(cmnd);
 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	}
 128out:
 129	spin_unlock_irqrestore(&devinfo->lock, flags);
 130}
 131
 132static 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
 143static void uas_add_work(struct scsi_cmnd *cmnd)
 144{
 145	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 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
 153static 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 = scsi_cmd_priv(cmnd);
 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
 177static 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
 200static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
 201			      int status)
 202{
 203	struct uas_cmd_info *ci = scsi_cmd_priv(cmnd);
 204
 205	if (status == -ENODEV) /* too late */
 206		return;
 207
 208	scmd_printk(KERN_INFO, cmnd,
 209		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
 210		    prefix, status, ci->uas_tag,
 211		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
 212		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
 213		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
 214		    (ci->state & ALLOC_DATA_OUT_URB)    ? " a-out" : "",
 215		    (ci->state & SUBMIT_DATA_OUT_URB)   ? " s-out" : "",
 216		    (ci->state & ALLOC_CMD_URB)         ? " a-cmd" : "",
 217		    (ci->state & SUBMIT_CMD_URB)        ? " s-cmd" : "",
 218		    (ci->state & COMMAND_INFLIGHT)      ? " CMD"   : "",
 219		    (ci->state & DATA_IN_URB_INFLIGHT)  ? " IN"    : "",
 220		    (ci->state & DATA_OUT_URB_INFLIGHT) ? " OUT"   : "",
 221		    (ci->state & COMMAND_ABORTED)       ? " abort" : "",
 222		    (ci->state & IS_IN_WORK_LIST)       ? " work"  : "");
 223	scsi_print_command(cmnd);
 224}
 225
 226static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
 227{
 228	struct uas_cmd_info *cmdinfo;
 229
 230	if (!cmnd)
 231		return;
 232
 233	cmdinfo = scsi_cmd_priv(cmnd);
 234
 235	if (cmdinfo->state & SUBMIT_CMD_URB)
 236		usb_free_urb(cmdinfo->cmd_urb);
 237
 238	/* data urbs may have never gotten their submit flag set */
 239	if (!(cmdinfo->state & DATA_IN_URB_INFLIGHT))
 240		usb_free_urb(cmdinfo->data_in_urb);
 241	if (!(cmdinfo->state & DATA_OUT_URB_INFLIGHT))
 242		usb_free_urb(cmdinfo->data_out_urb);
 243}
 244
 245static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
 246{
 247	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 248	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 249
 250	lockdep_assert_held(&devinfo->lock);
 251	if (cmdinfo->state & (COMMAND_INFLIGHT |
 252			      DATA_IN_URB_INFLIGHT |
 253			      DATA_OUT_URB_INFLIGHT |
 254			      COMMAND_ABORTED))
 255		return -EBUSY;
 256	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
 257	uas_free_unsubmitted_urbs(cmnd);
 258	scsi_done(cmnd);
 259	return 0;
 260}
 261
 262static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
 263			  unsigned direction)
 264{
 265	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 266	int err;
 267
 268	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
 269	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
 270	if (err) {
 271		uas_add_work(cmnd);
 272	}
 273}
 274
 275static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *cmnd)
 276{
 277	u8 response_code = riu->response_code;
 278
 279	switch (response_code) {
 280	case RC_INCORRECT_LUN:
 281		set_host_byte(cmnd, DID_BAD_TARGET);
 282		break;
 283	case RC_TMF_SUCCEEDED:
 284		set_host_byte(cmnd, DID_OK);
 285		break;
 286	case RC_TMF_NOT_SUPPORTED:
 287		set_host_byte(cmnd, DID_BAD_TARGET);
 288		break;
 289	default:
 290		uas_log_cmd_state(cmnd, "response iu", response_code);
 291		set_host_byte(cmnd, DID_ERROR);
 292		break;
 293	}
 294
 295	return response_code == RC_TMF_SUCCEEDED;
 296}
 297
 298static void uas_stat_cmplt(struct urb *urb)
 299{
 300	struct iu *iu = urb->transfer_buffer;
 301	struct Scsi_Host *shost = urb->context;
 302	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
 303	struct urb *data_in_urb = NULL;
 304	struct urb *data_out_urb = NULL;
 305	struct scsi_cmnd *cmnd;
 306	struct uas_cmd_info *cmdinfo;
 307	unsigned long flags;
 308	unsigned int idx;
 309	int status = urb->status;
 310	bool success;
 311
 312	if (status) {
 313		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 314			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
 315		goto bail;
 316	}
 317
 318	idx = be16_to_cpup(&iu->tag) - 1;
 319
 320	spin_lock_irqsave(&devinfo->lock, flags);
 321
 322	if (devinfo->resetting)
 323		goto out;
 324	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
 325		dev_err(&urb->dev->dev,
 326			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
 327		goto out;
 328	}
 329
 330	cmnd = devinfo->cmnd[idx];
 331	cmdinfo = scsi_cmd_priv(cmnd);
 332
 333	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
 334		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
 335		goto out;
 336	}
 337
 338	switch (iu->iu_id) {
 339	case IU_ID_STATUS:
 340		uas_sense(urb, cmnd);
 341		if (cmnd->result != 0) {
 342			/* cancel data transfers on error */
 343			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 344			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 345		}
 346		cmdinfo->state &= ~COMMAND_INFLIGHT;
 347		uas_try_complete(cmnd, __func__);
 348		break;
 349	case IU_ID_READ_READY:
 350		if (!cmdinfo->data_in_urb ||
 351				(cmdinfo->state & DATA_IN_URB_INFLIGHT)) {
 352			uas_log_cmd_state(cmnd, "unexpected read rdy", 0);
 353			break;
 354		}
 355		uas_xfer_data(urb, cmnd, SUBMIT_DATA_IN_URB);
 356		break;
 357	case IU_ID_WRITE_READY:
 358		if (!cmdinfo->data_out_urb ||
 359				(cmdinfo->state & DATA_OUT_URB_INFLIGHT)) {
 360			uas_log_cmd_state(cmnd, "unexpected write rdy", 0);
 361			break;
 362		}
 363		uas_xfer_data(urb, cmnd, SUBMIT_DATA_OUT_URB);
 364		break;
 365	case IU_ID_RESPONSE:
 366		cmdinfo->state &= ~COMMAND_INFLIGHT;
 367		success = uas_evaluate_response_iu((struct response_iu *)iu, cmnd);
 368		if (!success) {
 369			/* Error, cancel data transfers */
 370			data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 371			data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 372		}
 373		uas_try_complete(cmnd, __func__);
 374		break;
 375	default:
 376		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
 377	}
 378	spin_unlock_irqrestore(&devinfo->lock, flags);
 379	usb_free_urb(urb);
 380
 381	/* Unlinking of data urbs must be done without holding the lock */
 382	if (data_in_urb) {
 383		usb_unlink_urb(data_in_urb);
 384		usb_put_urb(data_in_urb);
 385	}
 386	if (data_out_urb) {
 387		usb_unlink_urb(data_out_urb);
 388		usb_put_urb(data_out_urb);
 389	}
 390	return;
 391
 392out:
 393	spin_unlock_irqrestore(&devinfo->lock, flags);
 394bail:
 395	usb_free_urb(urb);
 396}
 397
 398static void uas_data_cmplt(struct urb *urb)
 399{
 400	struct scsi_cmnd *cmnd = urb->context;
 401	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 402	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 403	struct scsi_data_buffer *sdb = &cmnd->sdb;
 404	unsigned long flags;
 405	int status = urb->status;
 406
 407	spin_lock_irqsave(&devinfo->lock, flags);
 408
 409	if (cmdinfo->data_in_urb == urb) {
 410		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
 411		cmdinfo->data_in_urb = NULL;
 412	} else if (cmdinfo->data_out_urb == urb) {
 413		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
 414		cmdinfo->data_out_urb = NULL;
 415	}
 416
 417	if (devinfo->resetting)
 418		goto out;
 419
 420	/* Data urbs should not complete before the cmd urb is submitted */
 421	if (cmdinfo->state & SUBMIT_CMD_URB) {
 422		uas_log_cmd_state(cmnd, "unexpected data cmplt", 0);
 423		goto out;
 424	}
 425
 426	if (status) {
 427		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 428			uas_log_cmd_state(cmnd, "data cmplt err", status);
 429		/* error: no data transfered */
 430		scsi_set_resid(cmnd, sdb->length);
 431		set_host_byte(cmnd, DID_ERROR);
 432	} else {
 433		scsi_set_resid(cmnd, sdb->length - urb->actual_length);
 434	}
 435	uas_try_complete(cmnd, __func__);
 436out:
 437	spin_unlock_irqrestore(&devinfo->lock, flags);
 438	usb_free_urb(urb);
 439}
 440
 441static void uas_cmd_cmplt(struct urb *urb)
 442{
 443	if (urb->status)
 444		dev_err(&urb->dev->dev, "cmd cmplt err %d\n", urb->status);
 445
 446	usb_free_urb(urb);
 447}
 448
 449static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 450				      struct scsi_cmnd *cmnd,
 451				      enum dma_data_direction dir)
 452{
 453	struct usb_device *udev = devinfo->udev;
 454	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 455	struct urb *urb = usb_alloc_urb(0, gfp);
 456	struct scsi_data_buffer *sdb = &cmnd->sdb;
 457	unsigned int pipe = (dir == DMA_FROM_DEVICE)
 458		? devinfo->data_in_pipe : devinfo->data_out_pipe;
 459
 460	if (!urb)
 461		goto out;
 462	usb_fill_bulk_urb(urb, udev, pipe, NULL, sdb->length,
 463			  uas_data_cmplt, cmnd);
 464	if (devinfo->use_streams)
 465		urb->stream_id = cmdinfo->uas_tag;
 466	urb->num_sgs = udev->bus->sg_tablesize ? sdb->table.nents : 0;
 467	urb->sg = sdb->table.sgl;
 468 out:
 469	return urb;
 470}
 471
 472static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 473				       struct scsi_cmnd *cmnd)
 474{
 475	struct usb_device *udev = devinfo->udev;
 476	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 477	struct urb *urb = usb_alloc_urb(0, gfp);
 478	struct sense_iu *iu;
 479
 480	if (!urb)
 481		goto out;
 482
 483	iu = kzalloc(sizeof(*iu), gfp);
 484	if (!iu)
 485		goto free;
 486
 487	usb_fill_bulk_urb(urb, udev, devinfo->status_pipe, iu, sizeof(*iu),
 488			  uas_stat_cmplt, cmnd->device->host);
 489	if (devinfo->use_streams)
 490		urb->stream_id = cmdinfo->uas_tag;
 491	urb->transfer_flags |= URB_FREE_BUFFER;
 492 out:
 493	return urb;
 494 free:
 495	usb_free_urb(urb);
 496	return NULL;
 497}
 498
 499static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 500					struct scsi_cmnd *cmnd)
 501{
 502	struct usb_device *udev = devinfo->udev;
 503	struct scsi_device *sdev = cmnd->device;
 504	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 505	struct urb *urb = usb_alloc_urb(0, gfp);
 506	struct command_iu *iu;
 507	int len;
 508
 509	if (!urb)
 510		goto out;
 511
 512	len = cmnd->cmd_len - 16;
 513	if (len < 0)
 514		len = 0;
 515	len = ALIGN(len, 4);
 516	iu = kzalloc(sizeof(*iu) + len, gfp);
 517	if (!iu)
 518		goto free;
 519
 520	iu->iu_id = IU_ID_COMMAND;
 521	iu->tag = cpu_to_be16(cmdinfo->uas_tag);
 522	iu->prio_attr = UAS_SIMPLE_TAG;
 523	iu->len = len;
 524	int_to_scsilun(sdev->lun, &iu->lun);
 525	memcpy(iu->cdb, cmnd->cmnd, cmnd->cmd_len);
 526
 527	usb_fill_bulk_urb(urb, udev, devinfo->cmd_pipe, iu, sizeof(*iu) + len,
 528							uas_cmd_cmplt, NULL);
 529	urb->transfer_flags |= URB_FREE_BUFFER;
 530 out:
 531	return urb;
 532 free:
 533	usb_free_urb(urb);
 534	return NULL;
 535}
 536
 537/*
 538 * Why should I request the Status IU before sending the Command IU?  Spec
 539 * says to, but also says the device may receive them in any order.  Seems
 540 * daft to me.
 541 */
 542
 543static int uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
 544{
 545	struct uas_dev_info *devinfo = cmnd->device->hostdata;
 546	struct urb *urb;
 547	int err;
 548
 549	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
 550	if (!urb)
 551		return -ENOMEM;
 552	usb_anchor_urb(urb, &devinfo->sense_urbs);
 553	err = usb_submit_urb(urb, gfp);
 554	if (err) {
 555		usb_unanchor_urb(urb);
 556		uas_log_cmd_state(cmnd, "sense submit err", err);
 557		usb_free_urb(urb);
 558	}
 559	return err;
 560}
 561
 562static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 563			   struct uas_dev_info *devinfo)
 564{
 565	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 566	int err;
 567
 568	lockdep_assert_held(&devinfo->lock);
 569	if (cmdinfo->state & SUBMIT_STATUS_URB) {
 570		err = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
 571		if (err)
 572			return err;
 573		cmdinfo->state &= ~SUBMIT_STATUS_URB;
 574	}
 575
 576	if (cmdinfo->state & ALLOC_DATA_IN_URB) {
 577		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 578							cmnd, DMA_FROM_DEVICE);
 579		if (!cmdinfo->data_in_urb)
 580			return -ENOMEM;
 581		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
 582	}
 583
 584	if (cmdinfo->state & SUBMIT_DATA_IN_URB) {
 585		usb_anchor_urb(cmdinfo->data_in_urb, &devinfo->data_urbs);
 586		err = usb_submit_urb(cmdinfo->data_in_urb, GFP_ATOMIC);
 587		if (err) {
 588			usb_unanchor_urb(cmdinfo->data_in_urb);
 589			uas_log_cmd_state(cmnd, "data in submit err", err);
 590			return err;
 591		}
 592		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
 593		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
 594	}
 595
 596	if (cmdinfo->state & ALLOC_DATA_OUT_URB) {
 597		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 598							cmnd, DMA_TO_DEVICE);
 599		if (!cmdinfo->data_out_urb)
 600			return -ENOMEM;
 601		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
 602	}
 603
 604	if (cmdinfo->state & SUBMIT_DATA_OUT_URB) {
 605		usb_anchor_urb(cmdinfo->data_out_urb, &devinfo->data_urbs);
 606		err = usb_submit_urb(cmdinfo->data_out_urb, GFP_ATOMIC);
 607		if (err) {
 608			usb_unanchor_urb(cmdinfo->data_out_urb);
 609			uas_log_cmd_state(cmnd, "data out submit err", err);
 610			return err;
 611		}
 612		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
 613		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
 614	}
 615
 616	if (cmdinfo->state & ALLOC_CMD_URB) {
 617		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
 618		if (!cmdinfo->cmd_urb)
 619			return -ENOMEM;
 620		cmdinfo->state &= ~ALLOC_CMD_URB;
 621	}
 622
 623	if (cmdinfo->state & SUBMIT_CMD_URB) {
 624		usb_anchor_urb(cmdinfo->cmd_urb, &devinfo->cmd_urbs);
 625		err = usb_submit_urb(cmdinfo->cmd_urb, GFP_ATOMIC);
 626		if (err) {
 627			usb_unanchor_urb(cmdinfo->cmd_urb);
 628			uas_log_cmd_state(cmnd, "cmd submit err", err);
 629			return err;
 630		}
 631		cmdinfo->cmd_urb = NULL;
 632		cmdinfo->state &= ~SUBMIT_CMD_URB;
 633		cmdinfo->state |= COMMAND_INFLIGHT;
 634	}
 635
 636	return 0;
 637}
 638
 639static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
 640{
 641	struct scsi_device *sdev = cmnd->device;
 642	struct uas_dev_info *devinfo = sdev->hostdata;
 643	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 644	unsigned long flags;
 645	int idx, err;
 646
 647	/* Re-check scsi_block_requests now that we've the host-lock */
 648	if (cmnd->device->host->host_self_blocked)
 649		return SCSI_MLQUEUE_DEVICE_BUSY;
 650
 651	if ((devinfo->flags & US_FL_NO_ATA_1X) &&
 652			(cmnd->cmnd[0] == ATA_12 || cmnd->cmnd[0] == ATA_16)) {
 653		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
 654		       sizeof(usb_stor_sense_invalidCDB));
 655		cmnd->result = SAM_STAT_CHECK_CONDITION;
 656		scsi_done(cmnd);
 657		return 0;
 658	}
 659
 660	spin_lock_irqsave(&devinfo->lock, flags);
 661
 662	if (devinfo->resetting) {
 663		set_host_byte(cmnd, DID_ERROR);
 664		scsi_done(cmnd);
 665		goto zombie;
 666	}
 667
 668	/* Find a free uas-tag */
 669	for (idx = 0; idx < devinfo->qdepth; idx++) {
 670		if (!devinfo->cmnd[idx])
 671			break;
 672	}
 673	if (idx == devinfo->qdepth) {
 674		spin_unlock_irqrestore(&devinfo->lock, flags);
 675		return SCSI_MLQUEUE_DEVICE_BUSY;
 676	}
 677
 678	memset(cmdinfo, 0, sizeof(*cmdinfo));
 679	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
 680	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
 681
 682	switch (cmnd->sc_data_direction) {
 683	case DMA_FROM_DEVICE:
 684		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
 685		break;
 686	case DMA_BIDIRECTIONAL:
 687		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
 688		fallthrough;
 689	case DMA_TO_DEVICE:
 690		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
 691		break;
 692	case DMA_NONE:
 693		break;
 694	}
 695
 696	if (!devinfo->use_streams)
 697		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
 698
 699	err = uas_submit_urbs(cmnd, devinfo);
 700	/*
 701	 * in case of fatal errors the SCSI layer is peculiar
 702	 * a command that has finished is a success for the purpose
 703	 * of queueing, no matter how fatal the error
 704	 */
 705	if (err == -ENODEV) {
 706		if (cmdinfo->state & (COMMAND_INFLIGHT | DATA_IN_URB_INFLIGHT |
 707				DATA_OUT_URB_INFLIGHT))
 708			goto out;
 709
 710		set_host_byte(cmnd, DID_NO_CONNECT);
 711		scsi_done(cmnd);
 712		goto zombie;
 713	}
 714	if (err) {
 715		/* If we did nothing, give up now */
 716		if (cmdinfo->state & SUBMIT_STATUS_URB) {
 717			spin_unlock_irqrestore(&devinfo->lock, flags);
 718			return SCSI_MLQUEUE_DEVICE_BUSY;
 719		}
 720		uas_add_work(cmnd);
 721	}
 722
 723out:
 724	devinfo->cmnd[idx] = cmnd;
 725zombie:
 726	spin_unlock_irqrestore(&devinfo->lock, flags);
 727	return 0;
 728}
 729
 730static DEF_SCSI_QCMD(uas_queuecommand)
 731
 732/*
 733 * For now we do not support actually sending an abort to the device, so
 734 * this eh always fails. Still we must define it to make sure that we've
 735 * dropped all references to the cmnd in question once this function exits.
 736 */
 737static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
 738{
 739	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 740	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 741	struct urb *data_in_urb = NULL;
 742	struct urb *data_out_urb = NULL;
 743	unsigned long flags;
 744
 745	spin_lock_irqsave(&devinfo->lock, flags);
 746
 747	uas_log_cmd_state(cmnd, __func__, 0);
 748
 749	/* Ensure that try_complete does not call scsi_done */
 750	cmdinfo->state |= COMMAND_ABORTED;
 751
 752	/* Drop all refs to this cmnd, kill data urbs to break their ref */
 753	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
 754	if (cmdinfo->state & DATA_IN_URB_INFLIGHT)
 755		data_in_urb = usb_get_urb(cmdinfo->data_in_urb);
 756	if (cmdinfo->state & DATA_OUT_URB_INFLIGHT)
 757		data_out_urb = usb_get_urb(cmdinfo->data_out_urb);
 758
 759	uas_free_unsubmitted_urbs(cmnd);
 760
 761	spin_unlock_irqrestore(&devinfo->lock, flags);
 762
 763	if (data_in_urb) {
 764		usb_kill_urb(data_in_urb);
 765		usb_put_urb(data_in_urb);
 766	}
 767	if (data_out_urb) {
 768		usb_kill_urb(data_out_urb);
 769		usb_put_urb(data_out_urb);
 770	}
 771
 772	return FAILED;
 773}
 774
 775static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
 776{
 777	struct scsi_device *sdev = cmnd->device;
 778	struct uas_dev_info *devinfo = sdev->hostdata;
 779	struct usb_device *udev = devinfo->udev;
 780	unsigned long flags;
 781	int err;
 782
 783	err = usb_lock_device_for_reset(udev, devinfo->intf);
 784	if (err) {
 785		shost_printk(KERN_ERR, sdev->host,
 786			     "%s FAILED to get lock err %d\n", __func__, err);
 787		return FAILED;
 788	}
 789
 790	shost_printk(KERN_INFO, sdev->host, "%s start\n", __func__);
 791
 792	spin_lock_irqsave(&devinfo->lock, flags);
 793	devinfo->resetting = 1;
 794	spin_unlock_irqrestore(&devinfo->lock, flags);
 795
 796	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
 797	usb_kill_anchored_urbs(&devinfo->sense_urbs);
 798	usb_kill_anchored_urbs(&devinfo->data_urbs);
 799	uas_zap_pending(devinfo, DID_RESET);
 800
 801	err = usb_reset_device(udev);
 802
 803	spin_lock_irqsave(&devinfo->lock, flags);
 804	devinfo->resetting = 0;
 805	spin_unlock_irqrestore(&devinfo->lock, flags);
 806
 807	usb_unlock_device(udev);
 808
 809	if (err) {
 810		shost_printk(KERN_INFO, sdev->host, "%s FAILED err %d\n",
 811			     __func__, err);
 812		return FAILED;
 813	}
 814
 815	shost_printk(KERN_INFO, sdev->host, "%s success\n", __func__);
 816	return SUCCESS;
 817}
 818
 819static int uas_target_alloc(struct scsi_target *starget)
 820{
 821	struct uas_dev_info *devinfo = (struct uas_dev_info *)
 822			dev_to_shost(starget->dev.parent)->hostdata;
 823
 824	if (devinfo->flags & US_FL_NO_REPORT_LUNS)
 825		starget->no_report_luns = 1;
 826
 827	return 0;
 828}
 829
 830static int uas_sdev_init(struct scsi_device *sdev)
 831{
 832	struct uas_dev_info *devinfo =
 833		(struct uas_dev_info *)sdev->host->hostdata;
 834
 835	/*
 836	 * Some USB storage devices reset if the IO advice hints grouping mode
 837	 * page is queried. Hence skip that mode page.
 838	 */
 839	sdev->sdev_bflags |= BLIST_SKIP_IO_HINTS;
 840
 841	sdev->hostdata = devinfo;
 842	return 0;
 843}
 844
 845static int uas_sdev_configure(struct scsi_device *sdev,
 846			      struct queue_limits *lim)
 847{
 848	struct uas_dev_info *devinfo = sdev->hostdata;
 849
 850	if (devinfo->flags & US_FL_MAX_SECTORS_64)
 851		lim->max_hw_sectors = 64;
 852	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
 853		lim->max_hw_sectors = 240;
 854
 855	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
 856		sdev->no_report_opcodes = 1;
 857
 858	/* A few buggy USB-ATA bridges don't understand FUA */
 859	if (devinfo->flags & US_FL_BROKEN_FUA)
 860		sdev->broken_fua = 1;
 861
 862	/* UAS also needs to support FL_ALWAYS_SYNC */
 863	if (devinfo->flags & US_FL_ALWAYS_SYNC) {
 864		sdev->skip_ms_page_3f = 1;
 865		sdev->skip_ms_page_8 = 1;
 866		sdev->wce_default_on = 1;
 867	}
 868
 869	/* Some disks cannot handle READ_CAPACITY_16 */
 870	if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
 871		sdev->no_read_capacity_16 = 1;
 872
 873	/* Some disks cannot handle WRITE_SAME */
 874	if (devinfo->flags & US_FL_NO_SAME)
 875		sdev->no_write_same = 1;
 876	/*
 877	 * Some disks return the total number of blocks in response
 878	 * to READ CAPACITY rather than the highest block number.
 879	 * If this device makes that mistake, tell the sd driver.
 880	 */
 881	if (devinfo->flags & US_FL_FIX_CAPACITY)
 882		sdev->fix_capacity = 1;
 883
 884	/*
 885	 * in some cases we have to guess
 886	 */
 887	if (devinfo->flags & US_FL_CAPACITY_HEURISTICS)
 888		sdev->guess_capacity = 1;
 889
 890	/*
 891	 * Some devices report generic values until the media has been
 892	 * accessed. Force a READ(10) prior to querying device
 893	 * characteristics.
 894	 */
 895	sdev->read_before_ms = 1;
 896
 897	/*
 898	 * Some devices don't like MODE SENSE with page=0x3f,
 899	 * which is the command used for checking if a device
 900	 * is write-protected.  Now that we tell the sd driver
 901	 * to do a 192-byte transfer with this command the
 902	 * majority of devices work fine, but a few still can't
 903	 * handle it.  The sd driver will simply assume those
 904	 * devices are write-enabled.
 905	 */
 906	if (devinfo->flags & US_FL_NO_WP_DETECT)
 907		sdev->skip_ms_page_3f = 1;
 908
 909	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
 910	return 0;
 911}
 912
 913static const struct scsi_host_template uas_host_template = {
 914	.module = THIS_MODULE,
 915	.name = "uas",
 916	.queuecommand = uas_queuecommand,
 917	.target_alloc = uas_target_alloc,
 918	.sdev_init = uas_sdev_init,
 919	.sdev_configure = uas_sdev_configure,
 920	.eh_abort_handler = uas_eh_abort_handler,
 921	.eh_device_reset_handler = uas_eh_device_reset_handler,
 922	.this_id = -1,
 923	.skip_settle_delay = 1,
 924	/*
 925	 * The protocol has no requirements on alignment in the strict sense.
 926	 * Controllers may or may not have alignment restrictions.
 927	 * As this is not exported, we use an extremely conservative guess.
 928	 */
 929	.dma_alignment = 511,
 930	.dma_boundary = PAGE_SIZE - 1,
 931	.cmd_size = sizeof(struct uas_cmd_info),
 932};
 933
 934#define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
 935		    vendorName, productName, useProtocol, useTransport, \
 936		    initFunction, flags) \
 937{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
 938	.driver_info = (flags) }
 939
 940static const struct usb_device_id uas_usb_ids[] = {
 941#	include "unusual_uas.h"
 942	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
 943	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
 944	{ }
 945};
 946MODULE_DEVICE_TABLE(usb, uas_usb_ids);
 947
 948#undef UNUSUAL_DEV
 949
 950static int uas_switch_interface(struct usb_device *udev,
 951				struct usb_interface *intf)
 952{
 953	struct usb_host_interface *alt;
 954
 955	alt = uas_find_uas_alt_setting(intf);
 956	if (!alt)
 957		return -ENODEV;
 958
 959	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
 960			alt->desc.bAlternateSetting);
 961}
 962
 963static int uas_configure_endpoints(struct uas_dev_info *devinfo)
 964{
 965	struct usb_host_endpoint *eps[4] = { };
 966	struct usb_device *udev = devinfo->udev;
 967	int r;
 968
 969	r = uas_find_endpoints(devinfo->intf->cur_altsetting, eps);
 970	if (r)
 971		return r;
 972
 973	devinfo->cmd_pipe = usb_sndbulkpipe(udev,
 974					    usb_endpoint_num(&eps[0]->desc));
 975	devinfo->status_pipe = usb_rcvbulkpipe(udev,
 976					    usb_endpoint_num(&eps[1]->desc));
 977	devinfo->data_in_pipe = usb_rcvbulkpipe(udev,
 978					    usb_endpoint_num(&eps[2]->desc));
 979	devinfo->data_out_pipe = usb_sndbulkpipe(udev,
 980					    usb_endpoint_num(&eps[3]->desc));
 981
 982	if (udev->speed < USB_SPEED_SUPER) {
 983		devinfo->qdepth = 32;
 984		devinfo->use_streams = 0;
 985	} else {
 986		devinfo->qdepth = usb_alloc_streams(devinfo->intf, eps + 1,
 987						    3, MAX_CMNDS, GFP_NOIO);
 988		if (devinfo->qdepth < 0)
 989			return devinfo->qdepth;
 990		devinfo->use_streams = 1;
 991	}
 992
 993	return 0;
 994}
 995
 996static void uas_free_streams(struct uas_dev_info *devinfo)
 997{
 998	struct usb_device *udev = devinfo->udev;
 999	struct usb_host_endpoint *eps[3];
1000
1001	eps[0] = usb_pipe_endpoint(udev, devinfo->status_pipe);
1002	eps[1] = usb_pipe_endpoint(udev, devinfo->data_in_pipe);
1003	eps[2] = usb_pipe_endpoint(udev, devinfo->data_out_pipe);
1004	usb_free_streams(devinfo->intf, eps, 3, GFP_NOIO);
1005}
1006
1007static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
1008{
1009	int result = -ENOMEM;
1010	struct Scsi_Host *shost = NULL;
1011	struct uas_dev_info *devinfo;
1012	struct usb_device *udev = interface_to_usbdev(intf);
1013	u64 dev_flags;
1014
1015	if (!uas_use_uas_driver(intf, id, &dev_flags))
1016		return -ENODEV;
1017
1018	if (uas_switch_interface(udev, intf))
1019		return -ENODEV;
1020
1021	shost = scsi_host_alloc(&uas_host_template,
1022				sizeof(struct uas_dev_info));
1023	if (!shost)
1024		goto set_alt0;
1025
1026	shost->max_cmd_len = 16 + 252;
1027	shost->max_id = 1;
1028	shost->max_lun = 256;
1029	shost->max_channel = 0;
1030	shost->sg_tablesize = udev->bus->sg_tablesize;
1031
1032	devinfo = (struct uas_dev_info *)shost->hostdata;
1033	devinfo->intf = intf;
1034	devinfo->udev = udev;
1035	devinfo->resetting = 0;
1036	devinfo->shutdown = 0;
1037	devinfo->flags = dev_flags;
1038	init_usb_anchor(&devinfo->cmd_urbs);
1039	init_usb_anchor(&devinfo->sense_urbs);
1040	init_usb_anchor(&devinfo->data_urbs);
1041	spin_lock_init(&devinfo->lock);
1042	INIT_WORK(&devinfo->work, uas_do_work);
1043	INIT_WORK(&devinfo->scan_work, uas_scan_work);
1044
1045	result = uas_configure_endpoints(devinfo);
1046	if (result)
1047		goto set_alt0;
1048
1049	/*
1050	 * 1 tag is reserved for untagged commands +
1051	 * 1 tag to avoid off by one errors in some bridge firmwares
1052	 */
1053	shost->can_queue = devinfo->qdepth - 2;
1054
1055	usb_set_intfdata(intf, shost);
1056	result = scsi_add_host(shost, &intf->dev);
1057	if (result)
1058		goto free_streams;
1059
1060	/* Submit the delayed_work for SCSI-device scanning */
1061	schedule_work(&devinfo->scan_work);
1062
1063	return result;
1064
1065free_streams:
1066	uas_free_streams(devinfo);
1067	usb_set_intfdata(intf, NULL);
1068set_alt0:
1069	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1070	if (shost)
1071		scsi_host_put(shost);
1072	return result;
1073}
1074
1075static int uas_cmnd_list_empty(struct uas_dev_info *devinfo)
1076{
1077	unsigned long flags;
1078	int i, r = 1;
1079
1080	spin_lock_irqsave(&devinfo->lock, flags);
1081
1082	for (i = 0; i < devinfo->qdepth; i++) {
1083		if (devinfo->cmnd[i]) {
1084			r = 0; /* Not empty */
1085			break;
1086		}
1087	}
1088
1089	spin_unlock_irqrestore(&devinfo->lock, flags);
1090
1091	return r;
1092}
1093
1094/*
1095 * Wait for any pending cmnds to complete, on usb-2 sense_urbs may temporarily
1096 * get empty while there still is more work to do due to sense-urbs completing
1097 * with a READ/WRITE_READY iu code, so keep waiting until the list gets empty.
1098 */
1099static int uas_wait_for_pending_cmnds(struct uas_dev_info *devinfo)
1100{
1101	unsigned long start_time;
1102	int r;
1103
1104	start_time = jiffies;
1105	do {
1106		flush_work(&devinfo->work);
1107
1108		r = usb_wait_anchor_empty_timeout(&devinfo->sense_urbs, 5000);
1109		if (r == 0)
1110			return -ETIME;
1111
1112		r = usb_wait_anchor_empty_timeout(&devinfo->data_urbs, 500);
1113		if (r == 0)
1114			return -ETIME;
1115
1116		if (time_after(jiffies, start_time + 5 * HZ))
1117			return -ETIME;
1118	} while (!uas_cmnd_list_empty(devinfo));
1119
1120	return 0;
1121}
1122
1123static int uas_pre_reset(struct usb_interface *intf)
1124{
1125	struct Scsi_Host *shost = usb_get_intfdata(intf);
1126	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1127	unsigned long flags;
1128
1129	if (devinfo->shutdown)
1130		return 0;
1131
1132	/* Block new requests */
1133	spin_lock_irqsave(shost->host_lock, flags);
1134	scsi_block_requests(shost);
1135	spin_unlock_irqrestore(shost->host_lock, flags);
1136
1137	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1138		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1139		scsi_unblock_requests(shost);
1140		return 1;
1141	}
1142
1143	uas_free_streams(devinfo);
1144
1145	return 0;
1146}
1147
1148static int uas_post_reset(struct usb_interface *intf)
1149{
1150	struct Scsi_Host *shost = usb_get_intfdata(intf);
1151	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1152	unsigned long flags;
1153	int err;
1154
1155	if (devinfo->shutdown)
1156		return 0;
1157
1158	err = uas_configure_endpoints(devinfo);
1159	if (err && err != -ENODEV)
1160		shost_printk(KERN_ERR, shost,
1161			     "%s: alloc streams error %d after reset",
1162			     __func__, err);
1163
1164	/* we must unblock the host in every case lest we deadlock */
1165	spin_lock_irqsave(shost->host_lock, flags);
1166	scsi_report_bus_reset(shost, 0);
1167	spin_unlock_irqrestore(shost->host_lock, flags);
1168
1169	scsi_unblock_requests(shost);
1170
1171	return err ? 1 : 0;
1172}
1173
1174static int uas_suspend(struct usb_interface *intf, pm_message_t message)
1175{
1176	struct Scsi_Host *shost = usb_get_intfdata(intf);
1177	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1178
1179	if (uas_wait_for_pending_cmnds(devinfo) != 0) {
1180		shost_printk(KERN_ERR, shost, "%s: timed out\n", __func__);
1181		return -ETIME;
1182	}
1183
1184	return 0;
1185}
1186
1187static int uas_resume(struct usb_interface *intf)
1188{
1189	return 0;
1190}
1191
1192static int uas_reset_resume(struct usb_interface *intf)
1193{
1194	struct Scsi_Host *shost = usb_get_intfdata(intf);
1195	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1196	unsigned long flags;
1197	int err;
1198
1199	err = uas_configure_endpoints(devinfo);
1200	if (err) {
1201		shost_printk(KERN_ERR, shost,
1202			     "%s: alloc streams error %d after reset",
1203			     __func__, err);
1204		return -EIO;
1205	}
1206
1207	spin_lock_irqsave(shost->host_lock, flags);
1208	scsi_report_bus_reset(shost, 0);
1209	spin_unlock_irqrestore(shost->host_lock, flags);
1210
1211	return 0;
1212}
1213
1214static void uas_disconnect(struct usb_interface *intf)
1215{
1216	struct Scsi_Host *shost = usb_get_intfdata(intf);
1217	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1218	unsigned long flags;
1219
1220	spin_lock_irqsave(&devinfo->lock, flags);
1221	devinfo->resetting = 1;
1222	spin_unlock_irqrestore(&devinfo->lock, flags);
1223
1224	cancel_work_sync(&devinfo->work);
1225	usb_kill_anchored_urbs(&devinfo->cmd_urbs);
1226	usb_kill_anchored_urbs(&devinfo->sense_urbs);
1227	usb_kill_anchored_urbs(&devinfo->data_urbs);
1228	uas_zap_pending(devinfo, DID_NO_CONNECT);
1229
1230	/*
1231	 * Prevent SCSI scanning (if it hasn't started yet)
1232	 * or wait for the SCSI-scanning routine to stop.
1233	 */
1234	cancel_work_sync(&devinfo->scan_work);
1235
1236	scsi_remove_host(shost);
1237	uas_free_streams(devinfo);
1238	scsi_host_put(shost);
1239}
1240
1241/*
1242 * Put the device back in usb-storage mode on shutdown, as some BIOS-es
1243 * hang on reboot when the device is still in uas mode. Note the reset is
1244 * necessary as some devices won't revert to usb-storage mode without it.
1245 */
1246static void uas_shutdown(struct usb_interface *intf)
1247{
1248	struct usb_device *udev = interface_to_usbdev(intf);
1249	struct Scsi_Host *shost = usb_get_intfdata(intf);
1250	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
1251
1252	if (system_state != SYSTEM_RESTART)
1253		return;
1254
1255	devinfo->shutdown = 1;
1256	uas_free_streams(devinfo);
1257	usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
1258	usb_reset_device(udev);
1259}
1260
1261static struct usb_driver uas_driver = {
1262	.name = "uas",
1263	.probe = uas_probe,
1264	.disconnect = uas_disconnect,
1265	.pre_reset = uas_pre_reset,
1266	.post_reset = uas_post_reset,
1267	.suspend = uas_suspend,
1268	.resume = uas_resume,
1269	.reset_resume = uas_reset_resume,
1270	.shutdown = uas_shutdown,
1271	.id_table = uas_usb_ids,
1272};
1273
1274static int __init uas_init(void)
1275{
1276	int rv;
1277
1278	workqueue = alloc_workqueue("uas", WQ_MEM_RECLAIM | WQ_PERCPU, 0);
1279	if (!workqueue)
1280		return -ENOMEM;
1281
1282	rv = usb_register(&uas_driver);
1283	if (rv) {
1284		destroy_workqueue(workqueue);
1285		return -ENOMEM;
1286	}
1287
1288	return 0;
1289}
1290
1291static void __exit uas_exit(void)
1292{
1293	usb_deregister(&uas_driver);
1294	destroy_workqueue(workqueue);
1295}
1296
1297module_init(uas_init);
1298module_exit(uas_exit);
1299
1300MODULE_DESCRIPTION("USB Attached SCSI driver");
1301MODULE_LICENSE("GPL");
1302MODULE_IMPORT_NS("USB_STORAGE");
1303MODULE_AUTHOR(
1304	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");