1 files changed, 232 insertions, 122 deletions

diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 5ef014ba6ae8..73b1981cb1d5 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * USB Attached SCSI
  * Note that this is not the same as the USB Mass Storage driver
@@ -5,8 +6,6 @@
  * Copyright Hans de Goede <hdegoede@redhat.com> for Red Hat, Inc. 2013 - 2016
  * Copyright Matthew Wilcox for Intel Corp, 2010
  * Copyright Sarah Sharp for Intel Corp, 2010
- *
- * Distributed under the terms of the GNU GPL, version two.
  */
 
 #include <linux/blkdev.h>
@@ -22,6 +21,7 @@
 #include <scsi/scsi.h>
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_dbg.h>
+#include <scsi/scsi_devinfo.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_host.h>
@@ -38,7 +38,7 @@ struct uas_dev_info {
 	struct usb_anchor cmd_urbs;
 	struct usb_anchor sense_urbs;
 	struct usb_anchor data_urbs;
-	unsigned long flags;
+	u64 flags;
 	int qdepth, resetting;
 	unsigned cmd_pipe, status_pipe, data_in_pipe, data_out_pipe;
 	unsigned use_streams:1;
@@ -46,6 +46,7 @@ struct uas_dev_info {
 	struct scsi_cmnd *cmnd[MAX_CMNDS];
 	spinlock_t lock;
 	struct work_struct work;
+	struct work_struct scan_work;      /* for async scanning */
 };
 
 enum {
@@ -81,6 +82,19 @@ static void uas_free_streams(struct uas_dev_info *devinfo);
 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
 				int status);
 
+/*
+ * This driver needs its own workqueue, as we need to control memory allocation.
+ *
+ * In the course of error handling and power management uas_wait_for_pending_cmnds()
+ * needs to flush pending work items. In these contexts we cannot allocate memory
+ * by doing block IO as we would deadlock. For the same reason we cannot wait
+ * for anything allocating memory not heeding these constraints.
+ *
+ * So we have to control all work items that can be on the workqueue we flush.
+ * Hence we cannot share a queue and need our own.
+ */
+static struct workqueue_struct *workqueue;
+
 static void uas_do_work(struct work_struct *work)
 {
 	struct uas_dev_info *devinfo =
@@ -100,7 +114,7 @@ static void uas_do_work(struct work_struct *work)
 			continue;
 
 		cmnd = devinfo->cmnd[i];
-		cmdinfo = (void *)&cmnd->SCp;
+		cmdinfo = scsi_cmd_priv(cmnd);
 
 		if (!(cmdinfo->state & IS_IN_WORK_LIST))
 			continue;
@@ -109,21 +123,31 @@ static void uas_do_work(struct work_struct *work)
 		if (!err)
 			cmdinfo->state &= ~IS_IN_WORK_LIST;
 		else
-			schedule_work(&devinfo->work);
+			queue_work(workqueue, &devinfo->work);
 	}
 out:
 	spin_unlock_irqrestore(&devinfo->lock, flags);
 }
 
-static void uas_add_work(struct uas_cmd_info *cmdinfo)
+static void uas_scan_work(struct work_struct *work)
+{
+	struct uas_dev_info *devinfo =
+		container_of(work, struct uas_dev_info, scan_work);
+	struct Scsi_Host *shost = usb_get_intfdata(devinfo->intf);
+
+	dev_dbg(&devinfo->intf->dev, "starting scan\n");
+	scsi_scan_host(shost);
+	dev_dbg(&devinfo->intf->dev, "scan complete\n");
+}
+
+static void uas_add_work(struct scsi_cmnd *cmnd)
 {
-	struct scsi_pointer *scp = (void *)cmdinfo;
-	struct scsi_cmnd *cmnd = container_of(scp, struct scsi_cmnd, SCp);
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
 
 	lockdep_assert_held(&devinfo->lock);
 	cmdinfo->state |= IS_IN_WORK_LIST;
-	schedule_work(&devinfo->work);
+	queue_work(workqueue, &devinfo->work);
 }
 
 static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
@@ -139,7 +163,7 @@ static void uas_zap_pending(struct uas_dev_info *devinfo, int result)
 			continue;
 
 		cmnd = devinfo->cmnd[i];
-		cmdinfo = (void *)&cmnd->SCp;
+		cmdinfo = scsi_cmd_priv(cmnd);
 		uas_log_cmd_state(cmnd, __func__, 0);
 		/* Sense urbs were killed, clear COMMAND_INFLIGHT manually */
 		cmdinfo->state &= ~COMMAND_INFLIGHT;
@@ -176,12 +200,14 @@ static void uas_sense(struct urb *urb, struct scsi_cmnd *cmnd)
 static void uas_log_cmd_state(struct scsi_cmnd *cmnd, const char *prefix,
 			      int status)
 {
-	struct uas_cmd_info *ci = (void *)&cmnd->SCp;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *ci = scsi_cmd_priv(cmnd);
+
+	if (status == -ENODEV) /* too late */
+		return;
 
 	scmd_printk(KERN_INFO, cmnd,
 		    "%s %d uas-tag %d inflight:%s%s%s%s%s%s%s%s%s%s%s%s ",
-		    prefix, status, cmdinfo->uas_tag,
+		    prefix, status, ci->uas_tag,
 		    (ci->state & SUBMIT_STATUS_URB)     ? " s-st"  : "",
 		    (ci->state & ALLOC_DATA_IN_URB)     ? " a-in"  : "",
 		    (ci->state & SUBMIT_DATA_IN_URB)    ? " s-in"  : "",
@@ -204,7 +230,7 @@ static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
 	if (!cmnd)
 		return;
 
-	cmdinfo = (void *)&cmnd->SCp;
+	cmdinfo = scsi_cmd_priv(cmnd);
 
 	if (cmdinfo->state & SUBMIT_CMD_URB)
 		usb_free_urb(cmdinfo->cmd_urb);
@@ -218,7 +244,7 @@ static void uas_free_unsubmitted_urbs(struct scsi_cmnd *cmnd)
 
 static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
 {
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 
 	lockdep_assert_held(&devinfo->lock);
@@ -229,20 +255,20 @@ static int uas_try_complete(struct scsi_cmnd *cmnd, const char *caller)
 		return -EBUSY;
 	devinfo->cmnd[cmdinfo->uas_tag - 1] = NULL;
 	uas_free_unsubmitted_urbs(cmnd);
-	cmnd->scsi_done(cmnd);
+	scsi_done(cmnd);
 	return 0;
 }
 
 static void uas_xfer_data(struct urb *urb, struct scsi_cmnd *cmnd,
 			  unsigned direction)
 {
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	int err;
 
 	cmdinfo->state |= direction | SUBMIT_STATUS_URB;
 	err = uas_submit_urbs(cmnd, cmnd->device->hostdata);
 	if (err) {
-		uas_add_work(cmdinfo);
+		uas_add_work(cmnd);
 	}
 }
 
@@ -252,17 +278,17 @@ static bool uas_evaluate_response_iu(struct response_iu *riu, struct scsi_cmnd *
 
 	switch (response_code) {
 	case RC_INCORRECT_LUN:
-		cmnd->result = DID_BAD_TARGET << 16;
+		set_host_byte(cmnd, DID_BAD_TARGET);
 		break;
 	case RC_TMF_SUCCEEDED:
-		cmnd->result = DID_OK << 16;
+		set_host_byte(cmnd, DID_OK);
 		break;
 	case RC_TMF_NOT_SUPPORTED:
-		cmnd->result = DID_TARGET_FAILURE << 16;
+		set_host_byte(cmnd, DID_BAD_TARGET);
 		break;
 	default:
 		uas_log_cmd_state(cmnd, "response iu", response_code);
-		cmnd->result = DID_ERROR << 16;
+		set_host_byte(cmnd, DID_ERROR);
 		break;
 	}
 
@@ -283,18 +309,18 @@ static void uas_stat_cmplt(struct urb *urb)
 	int status = urb->status;
 	bool success;
 
-	spin_lock_irqsave(&devinfo->lock, flags);
-
-	if (devinfo->resetting)
-		goto out;
-
 	if (status) {
 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 			dev_err(&urb->dev->dev, "stat urb: status %d\n", status);
-		goto out;
+		goto bail;
 	}
 
 	idx = be16_to_cpup(&iu->tag) - 1;
+
+	spin_lock_irqsave(&devinfo->lock, flags);
+
+	if (devinfo->resetting)
+		goto out;
 	if (idx >= MAX_CMNDS || !devinfo->cmnd[idx]) {
 		dev_err(&urb->dev->dev,
 			"stat urb: no pending cmd for uas-tag %d\n", idx + 1);
@@ -302,7 +328,7 @@ static void uas_stat_cmplt(struct urb *urb)
 	}
 
 	cmnd = devinfo->cmnd[idx];
-	cmdinfo = (void *)&cmnd->SCp;
+	cmdinfo = scsi_cmd_priv(cmnd);
 
 	if (!(cmdinfo->state & COMMAND_INFLIGHT)) {
 		uas_log_cmd_state(cmnd, "unexpected status cmplt", 0);
@@ -349,9 +375,8 @@ static void uas_stat_cmplt(struct urb *urb)
 	default:
 		uas_log_cmd_state(cmnd, "bogus IU", iu->iu_id);
 	}
-out:
-	usb_free_urb(urb);
 	spin_unlock_irqrestore(&devinfo->lock, flags);
+	usb_free_urb(urb);
 
 	/* Unlinking of data urbs must be done without holding the lock */
 	if (data_in_urb) {
@@ -362,32 +387,32 @@ out:
 		usb_unlink_urb(data_out_urb);
 		usb_put_urb(data_out_urb);
 	}
+	return;
+
+out:
+	spin_unlock_irqrestore(&devinfo->lock, flags);
+bail:
+	usb_free_urb(urb);
 }
 
 static void uas_data_cmplt(struct urb *urb)
 {
 	struct scsi_cmnd *cmnd = urb->context;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
-	struct scsi_data_buffer *sdb = NULL;
+	struct scsi_data_buffer *sdb = &cmnd->sdb;
 	unsigned long flags;
 	int status = urb->status;
 
 	spin_lock_irqsave(&devinfo->lock, flags);
 
 	if (cmdinfo->data_in_urb == urb) {
-		sdb = scsi_in(cmnd);
 		cmdinfo->state &= ~DATA_IN_URB_INFLIGHT;
 		cmdinfo->data_in_urb = NULL;
 	} else if (cmdinfo->data_out_urb == urb) {
-		sdb = scsi_out(cmnd);
 		cmdinfo->state &= ~DATA_OUT_URB_INFLIGHT;
 		cmdinfo->data_out_urb = NULL;
 	}
-	if (sdb == NULL) {
-		WARN_ON_ONCE(1);
-		goto out;
-	}
 
 	if (devinfo->resetting)
 		goto out;
@@ -402,14 +427,15 @@ static void uas_data_cmplt(struct urb *urb)
 		if (status != -ENOENT && status != -ECONNRESET && status != -ESHUTDOWN)
 			uas_log_cmd_state(cmnd, "data cmplt err", status);
 		/* error: no data transfered */
-		sdb->resid = sdb->length;
+		scsi_set_resid(cmnd, sdb->length);
+		set_host_byte(cmnd, DID_ERROR);
 	} else {
-		sdb->resid = sdb->length - urb->actual_length;
+		scsi_set_resid(cmnd, sdb->length - urb->actual_length);
 	}
 	uas_try_complete(cmnd, __func__);
 out:
-	usb_free_urb(urb);
 	spin_unlock_irqrestore(&devinfo->lock, flags);
+	usb_free_urb(urb);
 }
 
 static void uas_cmd_cmplt(struct urb *urb)
@@ -425,10 +451,9 @@ static struct urb *uas_alloc_data_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 				      enum dma_data_direction dir)
 {
 	struct usb_device *udev = devinfo->udev;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct urb *urb = usb_alloc_urb(0, gfp);
-	struct scsi_data_buffer *sdb = (dir == DMA_FROM_DEVICE)
-		? scsi_in(cmnd) : scsi_out(cmnd);
+	struct scsi_data_buffer *sdb = &cmnd->sdb;
 	unsigned int pipe = (dir == DMA_FROM_DEVICE)
 		? devinfo->data_in_pipe : devinfo->data_out_pipe;
 
@@ -448,7 +473,7 @@ static struct urb *uas_alloc_sense_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 				       struct scsi_cmnd *cmnd)
 {
 	struct usb_device *udev = devinfo->udev;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct urb *urb = usb_alloc_urb(0, gfp);
 	struct sense_iu *iu;
 
@@ -476,7 +501,7 @@ static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
 {
 	struct usb_device *udev = devinfo->udev;
 	struct scsi_device *sdev = cmnd->device;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct urb *urb = usb_alloc_urb(0, gfp);
 	struct command_iu *iu;
 	int len;
@@ -515,7 +540,7 @@ static struct urb *uas_alloc_cmd_urb(struct uas_dev_info *devinfo, gfp_t gfp,
  * daft to me.
  */
 
-static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
+static int uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
 {
 	struct uas_dev_info *devinfo = cmnd->device->hostdata;
 	struct urb *urb;
@@ -523,30 +548,28 @@ static struct urb *uas_submit_sense_urb(struct scsi_cmnd *cmnd, gfp_t gfp)
 
 	urb = uas_alloc_sense_urb(devinfo, gfp, cmnd);
 	if (!urb)
-		return NULL;
+		return -ENOMEM;
 	usb_anchor_urb(urb, &devinfo->sense_urbs);
 	err = usb_submit_urb(urb, gfp);
 	if (err) {
 		usb_unanchor_urb(urb);
 		uas_log_cmd_state(cmnd, "sense submit err", err);
 		usb_free_urb(urb);
-		return NULL;
 	}
-	return urb;
+	return err;
 }
 
 static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 			   struct uas_dev_info *devinfo)
 {
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
-	struct urb *urb;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	int err;
 
 	lockdep_assert_held(&devinfo->lock);
 	if (cmdinfo->state & SUBMIT_STATUS_URB) {
-		urb = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
-		if (!urb)
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+		err = uas_submit_sense_urb(cmnd, GFP_ATOMIC);
+		if (err)
+			return err;
 		cmdinfo->state &= ~SUBMIT_STATUS_URB;
 	}
 
@@ -554,7 +577,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 		cmdinfo->data_in_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 							cmnd, DMA_FROM_DEVICE);
 		if (!cmdinfo->data_in_urb)
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return -ENOMEM;
 		cmdinfo->state &= ~ALLOC_DATA_IN_URB;
 	}
 
@@ -564,7 +587,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 		if (err) {
 			usb_unanchor_urb(cmdinfo->data_in_urb);
 			uas_log_cmd_state(cmnd, "data in submit err", err);
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return err;
 		}
 		cmdinfo->state &= ~SUBMIT_DATA_IN_URB;
 		cmdinfo->state |= DATA_IN_URB_INFLIGHT;
@@ -574,7 +597,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 		cmdinfo->data_out_urb = uas_alloc_data_urb(devinfo, GFP_ATOMIC,
 							cmnd, DMA_TO_DEVICE);
 		if (!cmdinfo->data_out_urb)
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return -ENOMEM;
 		cmdinfo->state &= ~ALLOC_DATA_OUT_URB;
 	}
 
@@ -584,7 +607,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 		if (err) {
 			usb_unanchor_urb(cmdinfo->data_out_urb);
 			uas_log_cmd_state(cmnd, "data out submit err", err);
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return err;
 		}
 		cmdinfo->state &= ~SUBMIT_DATA_OUT_URB;
 		cmdinfo->state |= DATA_OUT_URB_INFLIGHT;
@@ -593,7 +616,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 	if (cmdinfo->state & ALLOC_CMD_URB) {
 		cmdinfo->cmd_urb = uas_alloc_cmd_urb(devinfo, GFP_ATOMIC, cmnd);
 		if (!cmdinfo->cmd_urb)
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return -ENOMEM;
 		cmdinfo->state &= ~ALLOC_CMD_URB;
 	}
 
@@ -603,7 +626,7 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 		if (err) {
 			usb_unanchor_urb(cmdinfo->cmd_urb);
 			uas_log_cmd_state(cmnd, "cmd submit err", err);
-			return SCSI_MLQUEUE_DEVICE_BUSY;
+			return err;
 		}
 		cmdinfo->cmd_urb = NULL;
 		cmdinfo->state &= ~SUBMIT_CMD_URB;
@@ -613,17 +636,14 @@ static int uas_submit_urbs(struct scsi_cmnd *cmnd,
 	return 0;
 }
 
-static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
-					void (*done)(struct scsi_cmnd *))
+static int uas_queuecommand_lck(struct scsi_cmnd *cmnd)
 {
 	struct scsi_device *sdev = cmnd->device;
 	struct uas_dev_info *devinfo = sdev->hostdata;
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	unsigned long flags;
 	int idx, err;
 
-	BUILD_BUG_ON(sizeof(struct uas_cmd_info) > sizeof(struct scsi_pointer));
-
 	/* Re-check scsi_block_requests now that we've the host-lock */
 	if (cmnd->device->host->host_self_blocked)
 		return SCSI_MLQUEUE_DEVICE_BUSY;
@@ -633,17 +653,16 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 		memcpy(cmnd->sense_buffer, usb_stor_sense_invalidCDB,
 		       sizeof(usb_stor_sense_invalidCDB));
 		cmnd->result = SAM_STAT_CHECK_CONDITION;
-		cmnd->scsi_done(cmnd);
+		scsi_done(cmnd);
 		return 0;
 	}
 
 	spin_lock_irqsave(&devinfo->lock, flags);
 
 	if (devinfo->resetting) {
-		cmnd->result = DID_ERROR << 16;
-		cmnd->scsi_done(cmnd);
-		spin_unlock_irqrestore(&devinfo->lock, flags);
-		return 0;
+		set_host_byte(cmnd, DID_ERROR);
+		scsi_done(cmnd);
+		goto zombie;
 	}
 
 	/* Find a free uas-tag */
@@ -656,8 +675,6 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 		return SCSI_MLQUEUE_DEVICE_BUSY;
 	}
 
-	cmnd->scsi_done = done;
-
 	memset(cmdinfo, 0, sizeof(*cmdinfo));
 	cmdinfo->uas_tag = idx + 1; /* uas-tag == usb-stream-id, so 1 based */
 	cmdinfo->state = SUBMIT_STATUS_URB | ALLOC_CMD_URB | SUBMIT_CMD_URB;
@@ -668,8 +685,10 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 		break;
 	case DMA_BIDIRECTIONAL:
 		cmdinfo->state |= ALLOC_DATA_IN_URB | SUBMIT_DATA_IN_URB;
+		fallthrough;
 	case DMA_TO_DEVICE:
 		cmdinfo->state |= ALLOC_DATA_OUT_URB | SUBMIT_DATA_OUT_URB;
+		break;
 	case DMA_NONE:
 		break;
 	}
@@ -678,16 +697,32 @@ static int uas_queuecommand_lck(struct scsi_cmnd *cmnd,
 		cmdinfo->state &= ~(SUBMIT_DATA_IN_URB | SUBMIT_DATA_OUT_URB);
 
 	err = uas_submit_urbs(cmnd, devinfo);
+	/*
+	 * in case of fatal errors the SCSI layer is peculiar
+	 * a command that has finished is a success for the purpose
+	 * of queueing, no matter how fatal the error
+	 */
+	if (err == -ENODEV) {
+		if (cmdinfo->state & (COMMAND_INFLIGHT | DATA_IN_URB_INFLIGHT |
+				DATA_OUT_URB_INFLIGHT))
+			goto out;
+
+		set_host_byte(cmnd, DID_NO_CONNECT);
+		scsi_done(cmnd);
+		goto zombie;
+	}
 	if (err) {
 		/* If we did nothing, give up now */
 		if (cmdinfo->state & SUBMIT_STATUS_URB) {
 			spin_unlock_irqrestore(&devinfo->lock, flags);
 			return SCSI_MLQUEUE_DEVICE_BUSY;
 		}
-		uas_add_work(cmdinfo);
+		uas_add_work(cmnd);
 	}
 
+out:
 	devinfo->cmnd[idx] = cmnd;
+zombie:
 	spin_unlock_irqrestore(&devinfo->lock, flags);
 	return 0;
 }
@@ -701,7 +736,7 @@ static DEF_SCSI_QCMD(uas_queuecommand)
  */
 static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
 {
-	struct uas_cmd_info *cmdinfo = (void *)&cmnd->SCp;
+	struct uas_cmd_info *cmdinfo = scsi_cmd_priv(cmnd);
 	struct uas_dev_info *devinfo = (void *)cmnd->device->hostdata;
 	struct urb *data_in_urb = NULL;
 	struct urb *data_out_urb = NULL;
@@ -737,7 +772,7 @@ static int uas_eh_abort_handler(struct scsi_cmnd *cmnd)
 	return FAILED;
 }
 
-static int uas_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
+static int uas_eh_device_reset_handler(struct scsi_cmnd *cmnd)
 {
 	struct scsi_device *sdev = cmnd->device;
 	struct uas_dev_info *devinfo = sdev->hostdata;
@@ -792,43 +827,31 @@ static int uas_target_alloc(struct scsi_target *starget)
 	return 0;
 }
 
-static int uas_slave_alloc(struct scsi_device *sdev)
+static int uas_sdev_init(struct scsi_device *sdev)
 {
 	struct uas_dev_info *devinfo =
 		(struct uas_dev_info *)sdev->host->hostdata;
 
-	sdev->hostdata = devinfo;
-
 	/*
-	 * USB has unusual DMA-alignment requirements: Although the
-	 * starting address of each scatter-gather element doesn't matter,
-	 * the length of each element except the last must be divisible
-	 * by the Bulk maxpacket value.  There's currently no way to
-	 * express this by block-layer constraints, so we'll cop out
-	 * and simply require addresses to be aligned at 512-byte
-	 * boundaries.  This is okay since most block I/O involves
-	 * hardware sectors that are multiples of 512 bytes in length,
-	 * and since host controllers up through USB 2.0 have maxpacket
-	 * values no larger than 512.
-	 *
-	 * But it doesn't suffice for Wireless USB, where Bulk maxpacket
-	 * values can be as large as 2048.  To make that work properly
-	 * will require changes to the block layer.
+	 * Some USB storage devices reset if the IO advice hints grouping mode
+	 * page is queried. Hence skip that mode page.
 	 */
-	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
-
-	if (devinfo->flags & US_FL_MAX_SECTORS_64)
-		blk_queue_max_hw_sectors(sdev->request_queue, 64);
-	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
-		blk_queue_max_hw_sectors(sdev->request_queue, 240);
+	sdev->sdev_bflags |= BLIST_SKIP_IO_HINTS;
 
+	sdev->hostdata = devinfo;
 	return 0;
 }
 
-static int uas_slave_configure(struct scsi_device *sdev)
+static int uas_sdev_configure(struct scsi_device *sdev,
+			      struct queue_limits *lim)
 {
 	struct uas_dev_info *devinfo = sdev->hostdata;
 
+	if (devinfo->flags & US_FL_MAX_SECTORS_64)
+		lim->max_hw_sectors = 64;
+	else if (devinfo->flags & US_FL_MAX_SECTORS_240)
+		lim->max_hw_sectors = 240;
+
 	if (devinfo->flags & US_FL_NO_REPORT_OPCODES)
 		sdev->no_report_opcodes = 1;
 
@@ -836,22 +859,76 @@ static int uas_slave_configure(struct scsi_device *sdev)
 	if (devinfo->flags & US_FL_BROKEN_FUA)
 		sdev->broken_fua = 1;
 
+	/* UAS also needs to support FL_ALWAYS_SYNC */
+	if (devinfo->flags & US_FL_ALWAYS_SYNC) {
+		sdev->skip_ms_page_3f = 1;
+		sdev->skip_ms_page_8 = 1;
+		sdev->wce_default_on = 1;
+	}
+
+	/* Some disks cannot handle READ_CAPACITY_16 */
+	if (devinfo->flags & US_FL_NO_READ_CAPACITY_16)
+		sdev->no_read_capacity_16 = 1;
+
+	/* Some disks cannot handle WRITE_SAME */
+	if (devinfo->flags & US_FL_NO_SAME)
+		sdev->no_write_same = 1;
+	/*
+	 * Some disks return the total number of blocks in response
+	 * to READ CAPACITY rather than the highest block number.
+	 * If this device makes that mistake, tell the sd driver.
+	 */
+	if (devinfo->flags & US_FL_FIX_CAPACITY)
+		sdev->fix_capacity = 1;
+
+	/*
+	 * in some cases we have to guess
+	 */
+	if (devinfo->flags & US_FL_CAPACITY_HEURISTICS)
+		sdev->guess_capacity = 1;
+
+	/*
+	 * Some devices report generic values until the media has been
+	 * accessed. Force a READ(10) prior to querying device
+	 * characteristics.
+	 */
+	sdev->read_before_ms = 1;
+
+	/*
+	 * Some devices don't like MODE SENSE with page=0x3f,
+	 * which is the command used for checking if a device
+	 * is write-protected.  Now that we tell the sd driver
+	 * to do a 192-byte transfer with this command the
+	 * majority of devices work fine, but a few still can't
+	 * handle it.  The sd driver will simply assume those
+	 * devices are write-enabled.
+	 */
+	if (devinfo->flags & US_FL_NO_WP_DETECT)
+		sdev->skip_ms_page_3f = 1;
+
 	scsi_change_queue_depth(sdev, devinfo->qdepth - 2);
 	return 0;
 }
 
-static struct scsi_host_template uas_host_template = {
+static const struct scsi_host_template uas_host_template = {
 	.module = THIS_MODULE,
 	.name = "uas",
 	.queuecommand = uas_queuecommand,
 	.target_alloc = uas_target_alloc,
-	.slave_alloc = uas_slave_alloc,
-	.slave_configure = uas_slave_configure,
+	.sdev_init = uas_sdev_init,
+	.sdev_configure = uas_sdev_configure,
 	.eh_abort_handler = uas_eh_abort_handler,
-	.eh_bus_reset_handler = uas_eh_bus_reset_handler,
+	.eh_device_reset_handler = uas_eh_device_reset_handler,
 	.this_id = -1,
-	.sg_tablesize = SG_NONE,
 	.skip_settle_delay = 1,
+	/*
+	 * The protocol has no requirements on alignment in the strict sense.
+	 * Controllers may or may not have alignment restrictions.
+	 * As this is not exported, we use an extremely conservative guess.
+	 */
+	.dma_alignment = 511,
+	.dma_boundary = PAGE_SIZE - 1,
+	.cmd_size = sizeof(struct uas_cmd_info),
 };
 
 #define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
@@ -860,7 +937,7 @@ static struct scsi_host_template uas_host_template = {
 { USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
 	.driver_info = (flags) }
 
-static struct usb_device_id uas_usb_ids[] = {
+static const struct usb_device_id uas_usb_ids[] = {
 #	include "unusual_uas.h"
 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_BULK) },
 	{ USB_INTERFACE_INFO(USB_CLASS_MASS_STORAGE, USB_SC_SCSI, USB_PR_UAS) },
@@ -873,14 +950,14 @@ MODULE_DEVICE_TABLE(usb, uas_usb_ids);
 static int uas_switch_interface(struct usb_device *udev,
 				struct usb_interface *intf)
 {
-	int alt;
+	struct usb_host_interface *alt;
 
 	alt = uas_find_uas_alt_setting(intf);
-	if (alt < 0)
-		return alt;
+	if (!alt)
+		return -ENODEV;
 
-	return usb_set_interface(udev,
-			intf->altsetting[0].desc.bInterfaceNumber, alt);
+	return usb_set_interface(udev, alt->desc.bInterfaceNumber,
+			alt->desc.bAlternateSetting);
 }
 
 static int uas_configure_endpoints(struct uas_dev_info *devinfo)
@@ -933,7 +1010,7 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	struct Scsi_Host *shost = NULL;
 	struct uas_dev_info *devinfo;
 	struct usb_device *udev = interface_to_usbdev(intf);
-	unsigned long dev_flags;
+	u64 dev_flags;
 
 	if (!uas_use_uas_driver(intf, id, &dev_flags))
 		return -ENODEV;
@@ -963,6 +1040,7 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	init_usb_anchor(&devinfo->data_urbs);
 	spin_lock_init(&devinfo->lock);
 	INIT_WORK(&devinfo->work, uas_do_work);
+	INIT_WORK(&devinfo->scan_work, uas_scan_work);
 
 	result = uas_configure_endpoints(devinfo);
 	if (result)
@@ -979,7 +1057,9 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	if (result)
 		goto free_streams;
 
-	scsi_scan_host(shost);
+	/* Submit the delayed_work for SCSI-device scanning */
+	schedule_work(&devinfo->scan_work);
+
 	return result;
 
 free_streams:
@@ -1076,20 +1156,19 @@ static int uas_post_reset(struct usb_interface *intf)
 		return 0;
 
 	err = uas_configure_endpoints(devinfo);
-	if (err) {
+	if (err && err != -ENODEV)
 		shost_printk(KERN_ERR, shost,
 			     "%s: alloc streams error %d after reset",
 			     __func__, err);
-		return 1;
-	}
 
+	/* we must unblock the host in every case lest we deadlock */
 	spin_lock_irqsave(shost->host_lock, flags);
 	scsi_report_bus_reset(shost, 0);
 	spin_unlock_irqrestore(shost->host_lock, flags);
 
 	scsi_unblock_requests(shost);
 
-	return 0;
+	return err ? 1 : 0;
 }
 
 static int uas_suspend(struct usb_interface *intf, pm_message_t message)
@@ -1148,6 +1227,12 @@ static void uas_disconnect(struct usb_interface *intf)
 	usb_kill_anchored_urbs(&devinfo->data_urbs);
 	uas_zap_pending(devinfo, DID_NO_CONNECT);
 
+	/*
+	 * Prevent SCSI scanning (if it hasn't started yet)
+	 * or wait for the SCSI-scanning routine to stop.
+	 */
+	cancel_work_sync(&devinfo->scan_work);
+
 	scsi_remove_host(shost);
 	uas_free_streams(devinfo);
 	scsi_host_put(shost);
@@ -1158,9 +1243,8 @@ static void uas_disconnect(struct usb_interface *intf)
  * hang on reboot when the device is still in uas mode. Note the reset is
  * necessary as some devices won't revert to usb-storage mode without it.
  */
-static void uas_shutdown(struct device *dev)
+static void uas_shutdown(struct usb_interface *intf)
 {
-	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_device *udev = interface_to_usbdev(intf);
 	struct Scsi_Host *shost = usb_get_intfdata(intf);
 	struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
@@ -1183,12 +1267,38 @@ static struct usb_driver uas_driver = {
 	.suspend = uas_suspend,
 	.resume = uas_resume,
 	.reset_resume = uas_reset_resume,
-	.drvwrap.driver.shutdown = uas_shutdown,
+	.shutdown = uas_shutdown,
 	.id_table = uas_usb_ids,
 };
 
-module_usb_driver(uas_driver);
+static int __init uas_init(void)
+{
+	int rv;
+
+	workqueue = alloc_workqueue("uas", WQ_MEM_RECLAIM | WQ_PERCPU, 0);
+	if (!workqueue)
+		return -ENOMEM;
+
+	rv = usb_register(&uas_driver);
+	if (rv) {
+		destroy_workqueue(workqueue);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void __exit uas_exit(void)
+{
+	usb_deregister(&uas_driver);
+	destroy_workqueue(workqueue);
+}
+
+module_init(uas_init);
+module_exit(uas_exit);
 
+MODULE_DESCRIPTION("USB Attached SCSI driver");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("USB_STORAGE");
 MODULE_AUTHOR(
 	"Hans de Goede <hdegoede@redhat.com>, Matthew Wilcox and Sarah Sharp");