File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
new file mode 100644
index 0000000..dba5136
--- /dev/null
+++ b/drivers/usb/storage/scsiglue.c
@@ -0,0 +1,607 @@
+/* Driver for USB Mass Storage compliant devices
+ * SCSI layer glue code
+ *
+ * Current development and maintenance by:
+ *   (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
+ *
+ * Developed with the assistance of:
+ *   (c) 2000 David L. Brown, Jr. (usb-storage@davidb.org)
+ *   (c) 2000 Stephen J. Gowdy (SGowdy@lbl.gov)
+ *
+ * Initial work by:
+ *   (c) 1999 Michael Gee (michael@linuxspecific.com)
+ *
+ * This driver is based on the 'USB Mass Storage Class' document. This
+ * describes in detail the protocol used to communicate with such
+ * devices.  Clearly, the designers had SCSI and ATAPI commands in
+ * mind when they created this document.  The commands are all very
+ * similar to commands in the SCSI-II and ATAPI specifications.
+ *
+ * It is important to note that in a number of cases this class
+ * exhibits class-specific exemptions from the USB specification.
+ * Notably the usage of NAK, STALL and ACK differs from the norm, in
+ * that they are used to communicate wait, failed and OK on commands.
+ *
+ * Also, for certain devices, the interrupt endpoint is used to convey
+ * status of a command.
+ *
+ * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
+ * information about this driver.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/mutex.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_devinfo.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+
+#include "usb.h"
+#include "scsiglue.h"
+#include "debug.h"
+#include "transport.h"
+#include "protocol.h"
+
+/* Vendor IDs for companies that seem to include the READ CAPACITY bug
+ * in all their devices
+ */
+#define VENDOR_ID_NOKIA		0x0421
+#define VENDOR_ID_NIKON		0x04b0
+#define VENDOR_ID_PENTAX	0x0a17
+#define VENDOR_ID_MOTOROLA	0x22b8
+
+/***********************************************************************
+ * Host functions 
+ ***********************************************************************/
+
+static const char* host_info(struct Scsi_Host *host)
+{
+	struct us_data *us = host_to_us(host);
+	return us->scsi_name;
+}
+
+static int slave_alloc (struct scsi_device *sdev)
+{
+	struct us_data *us = host_to_us(sdev->host);
+
+	/*
+	 * Set the INQUIRY transfer length to 36.  We don't use any of
+	 * the extra data and many devices choke if asked for more or
+	 * less than 36 bytes.
+	 */
+	sdev->inquiry_len = 36;
+
+	/* 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.
+	 */
+	blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
+
+	/* Tell the SCSI layer if we know there is more than one LUN */
+	if (us->protocol == USB_PR_BULK && us->max_lun > 0)
+		sdev->sdev_bflags |= BLIST_FORCELUN;
+
+	return 0;
+}
+
+static int slave_configure(struct scsi_device *sdev)
+{
+	struct us_data *us = host_to_us(sdev->host);
+
+	/* Many devices have trouble transferring more than 32KB at a time,
+	 * while others have trouble with more than 64K. At this time we
+	 * are limiting both to 32K (64 sectores).
+	 */
+	if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
+		unsigned int max_sectors = 64;
+
+		if (us->fflags & US_FL_MAX_SECTORS_MIN)
+			max_sectors = PAGE_CACHE_SIZE >> 9;
+		if (queue_max_hw_sectors(sdev->request_queue) > max_sectors)
+			blk_queue_max_hw_sectors(sdev->request_queue,
+					      max_sectors);
+	} else if (sdev->type == TYPE_TAPE) {
+		/* Tapes need much higher max_sector limits, so just
+		 * raise it to the maximum possible (4 GB / 512) and
+		 * let the queue segment size sort out the real limit.
+		 */
+		blk_queue_max_hw_sectors(sdev->request_queue, 0x7FFFFF);
+	}
+
+	/* Some USB host controllers can't do DMA; they have to use PIO.
+	 * They indicate this by setting their dma_mask to NULL.  For
+	 * such controllers we need to make sure the block layer sets
+	 * up bounce buffers in addressable memory.
+	 */
+	if (!us->pusb_dev->bus->controller->dma_mask)
+		blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_HIGH);
+
+	/* We can't put these settings in slave_alloc() because that gets
+	 * called before the device type is known.  Consequently these
+	 * settings can't be overridden via the scsi devinfo mechanism. */
+	if (sdev->type == TYPE_DISK) {
+
+		/* Some vendors seem to put the READ CAPACITY bug into
+		 * all their devices -- primarily makers of cell phones
+		 * and digital cameras.  Since these devices always use
+		 * flash media and can be expected to have an even number
+		 * of sectors, we will always enable the CAPACITY_HEURISTICS
+		 * flag unless told otherwise. */
+		switch (le16_to_cpu(us->pusb_dev->descriptor.idVendor)) {
+		case VENDOR_ID_NOKIA:
+		case VENDOR_ID_NIKON:
+		case VENDOR_ID_PENTAX:
+		case VENDOR_ID_MOTOROLA:
+			if (!(us->fflags & (US_FL_FIX_CAPACITY |
+					US_FL_CAPACITY_OK)))
+				us->fflags |= US_FL_CAPACITY_HEURISTICS;
+			break;
+		}
+
+		/* Disk-type devices use MODE SENSE(6) if the protocol
+		 * (SubClass) is Transparent SCSI, otherwise they use
+		 * MODE SENSE(10). */
+		if (us->subclass != USB_SC_SCSI && us->subclass != USB_SC_CYP_ATACB)
+			sdev->use_10_for_ms = 1;
+
+		/* Many disks only accept MODE SENSE transfer lengths of
+		 * 192 bytes (that's what Windows uses). */
+		sdev->use_192_bytes_for_3f = 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 (us->fflags & US_FL_NO_WP_DETECT)
+			sdev->skip_ms_page_3f = 1;
+
+		/* A number of devices have problems with MODE SENSE for
+		 * page x08, so we will skip it. */
+		sdev->skip_ms_page_8 = 1;
+
+		/* Some devices don't handle VPD pages correctly */
+		sdev->skip_vpd_pages = 1;
+
+		/* Do not attempt to use REPORT SUPPORTED OPERATION CODES */
+		sdev->no_report_opcodes = 1;
+
+		/* Do not attempt to use WRITE 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 (us->fflags & US_FL_FIX_CAPACITY)
+			sdev->fix_capacity = 1;
+
+		/* A few disks have two indistinguishable version, one of
+		 * which reports the correct capacity and the other does not.
+		 * The sd driver has to guess which is the case. */
+		if (us->fflags & US_FL_CAPACITY_HEURISTICS)
+			sdev->guess_capacity = 1;
+
+		/* Some devices cannot handle READ_CAPACITY_16 */
+		if (us->fflags & US_FL_NO_READ_CAPACITY_16)
+			sdev->no_read_capacity_16 = 1;
+
+		/*
+		 * Many devices do not respond properly to READ_CAPACITY_16.
+		 * Tell the SCSI layer to try READ_CAPACITY_10 first.
+		 * However some USB 3.0 drive enclosures return capacity
+		 * modulo 2TB. Those must use READ_CAPACITY_16
+		 */
+		if (!(us->fflags & US_FL_NEEDS_CAP16))
+			sdev->try_rc_10_first = 1;
+
+		/* assume SPC3 or latter devices support sense size > 18 */
+		if (sdev->scsi_level > SCSI_SPC_2)
+			us->fflags |= US_FL_SANE_SENSE;
+
+		/* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
+		 * Hardware Error) when any low-level error occurs,
+		 * recoverable or not.  Setting this flag tells the SCSI
+		 * midlayer to retry such commands, which frequently will
+		 * succeed and fix the error.  The worst this can lead to
+		 * is an occasional series of retries that will all fail. */
+		sdev->retry_hwerror = 1;
+
+		/* USB disks should allow restart.  Some drives spin down
+		 * automatically, requiring a START-STOP UNIT command. */
+		sdev->allow_restart = 1;
+
+		/* Some USB cardreaders have trouble reading an sdcard's last
+		 * sector in a larger then 1 sector read, since the performance
+		 * impact is negligible we set this flag for all USB disks */
+		sdev->last_sector_bug = 1;
+
+		/* Enable last-sector hacks for single-target devices using
+		 * the Bulk-only transport, unless we already know the
+		 * capacity will be decremented or is correct. */
+		if (!(us->fflags & (US_FL_FIX_CAPACITY | US_FL_CAPACITY_OK |
+					US_FL_SCM_MULT_TARG)) &&
+				us->protocol == USB_PR_BULK)
+			us->use_last_sector_hacks = 1;
+
+		/* Check if write cache default on flag is set or not */
+		if (us->fflags & US_FL_WRITE_CACHE)
+			sdev->wce_default_on = 1;
+
+		/* A few buggy USB-ATA bridges don't understand FUA */
+		if (us->fflags & US_FL_BROKEN_FUA)
+			sdev->broken_fua = 1;
+
+	} else {
+
+		/* Non-disk-type devices don't need to blacklist any pages
+		 * or to force 192-byte transfer lengths for MODE SENSE.
+		 * But they do need to use MODE SENSE(10). */
+		sdev->use_10_for_ms = 1;
+
+		/* Some (fake) usb cdrom devices don't like READ_DISC_INFO */
+		if (us->fflags & US_FL_NO_READ_DISC_INFO)
+			sdev->no_read_disc_info = 1;
+	}
+
+	/* The CB and CBI transports have no way to pass LUN values
+	 * other than the bits in the second byte of a CDB.  But those
+	 * bits don't get set to the LUN value if the device reports
+	 * scsi_level == 0 (UNKNOWN).  Hence such devices must necessarily
+	 * be single-LUN.
+	 */
+	if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
+			sdev->scsi_level == SCSI_UNKNOWN)
+		us->max_lun = 0;
+
+	/* Some devices choke when they receive a PREVENT-ALLOW MEDIUM
+	 * REMOVAL command, so suppress those commands. */
+	if (us->fflags & US_FL_NOT_LOCKABLE)
+		sdev->lockable = 0;
+
+	/* this is to satisfy the compiler, tho I don't think the 
+	 * return code is ever checked anywhere. */
+	return 0;
+}
+
+static int target_alloc(struct scsi_target *starget)
+{
+	struct us_data *us = host_to_us(dev_to_shost(starget->dev.parent));
+
+	/*
+	 * Some USB drives don't support REPORT LUNS, even though they
+	 * report a SCSI revision level above 2.  Tell the SCSI layer
+	 * not to issue that command; it will perform a normal sequential
+	 * scan instead.
+	 */
+	starget->no_report_luns = 1;
+
+	/*
+	 * The UFI spec treats the Peripheral Qualifier bits in an
+	 * INQUIRY result as reserved and requires devices to set them
+	 * to 0.  However the SCSI spec requires these bits to be set
+	 * to 3 to indicate when a LUN is not present.
+	 *
+	 * Let the scanning code know if this target merely sets
+	 * Peripheral Device Type to 0x1f to indicate no LUN.
+	 */
+	if (us->subclass == USB_SC_UFI)
+		starget->pdt_1f_for_no_lun = 1;
+
+	return 0;
+}
+
+/* queue a command */
+/* This is always called with scsi_lock(host) held */
+static int queuecommand_lck(struct scsi_cmnd *srb,
+			void (*done)(struct scsi_cmnd *))
+{
+	struct us_data *us = host_to_us(srb->device->host);
+
+	/* check for state-transition errors */
+	if (us->srb != NULL) {
+		printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
+			__func__, us->srb);
+		return SCSI_MLQUEUE_HOST_BUSY;
+	}
+
+	/* fail the command if we are disconnecting */
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
+		usb_stor_dbg(us, "Fail command during disconnect\n");
+		srb->result = DID_NO_CONNECT << 16;
+		done(srb);
+		return 0;
+	}
+
+	/* enqueue the command and wake up the control thread */
+	srb->scsi_done = done;
+	us->srb = srb;
+	complete(&us->cmnd_ready);
+
+	return 0;
+}
+
+static DEF_SCSI_QCMD(queuecommand)
+
+/***********************************************************************
+ * Error handling functions
+ ***********************************************************************/
+
+/* Command timeout and abort */
+static int command_abort(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+
+	usb_stor_dbg(us, "%s called\n", __func__);
+
+	/* us->srb together with the TIMED_OUT, RESETTING, and ABORTING
+	 * bits are protected by the host lock. */
+	scsi_lock(us_to_host(us));
+
+	/* Is this command still active? */
+	if (us->srb != srb) {
+		scsi_unlock(us_to_host(us));
+		usb_stor_dbg(us, "-- nothing to abort\n");
+		return FAILED;
+	}
+
+	/* Set the TIMED_OUT bit.  Also set the ABORTING bit, but only if
+	 * a device reset isn't already in progress (to avoid interfering
+	 * with the reset).  Note that we must retain the host lock while
+	 * calling usb_stor_stop_transport(); otherwise it might interfere
+	 * with an auto-reset that begins as soon as we release the lock. */
+	set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
+	if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
+		set_bit(US_FLIDX_ABORTING, &us->dflags);
+		usb_stor_stop_transport(us);
+	}
+	scsi_unlock(us_to_host(us));
+
+	/* Wait for the aborted command to finish */
+	wait_for_completion(&us->notify);
+	return SUCCESS;
+}
+
+/* This invokes the transport reset mechanism to reset the state of the
+ * device */
+static int device_reset(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+	int result;
+
+	usb_stor_dbg(us, "%s called\n", __func__);
+
+	/* lock the device pointers and do the reset */
+	mutex_lock(&(us->dev_mutex));
+	result = us->transport_reset(us);
+	mutex_unlock(&us->dev_mutex);
+
+	return result < 0 ? FAILED : SUCCESS;
+}
+
+/* Simulate a SCSI bus reset by resetting the device's USB port. */
+static int bus_reset(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+	int result;
+
+	usb_stor_dbg(us, "%s called\n", __func__);
+
+	result = usb_stor_port_reset(us);
+	return result < 0 ? FAILED : SUCCESS;
+}
+
+/* Report a driver-initiated device reset to the SCSI layer.
+ * Calling this for a SCSI-initiated reset is unnecessary but harmless.
+ * The caller must own the SCSI host lock. */
+void usb_stor_report_device_reset(struct us_data *us)
+{
+	int i;
+	struct Scsi_Host *host = us_to_host(us);
+
+	scsi_report_device_reset(host, 0, 0);
+	if (us->fflags & US_FL_SCM_MULT_TARG) {
+		for (i = 1; i < host->max_id; ++i)
+			scsi_report_device_reset(host, 0, i);
+	}
+}
+
+/* Report a driver-initiated bus reset to the SCSI layer.
+ * Calling this for a SCSI-initiated reset is unnecessary but harmless.
+ * The caller must not own the SCSI host lock. */
+void usb_stor_report_bus_reset(struct us_data *us)
+{
+	struct Scsi_Host *host = us_to_host(us);
+
+	scsi_lock(host);
+	scsi_report_bus_reset(host, 0);
+	scsi_unlock(host);
+}
+
+/***********************************************************************
+ * /proc/scsi/ functions
+ ***********************************************************************/
+
+static int write_info(struct Scsi_Host *host, char *buffer, int length)
+{
+	/* if someone is sending us data, just throw it away */
+	return length;
+}
+
+static int show_info (struct seq_file *m, struct Scsi_Host *host)
+{
+	struct us_data *us = host_to_us(host);
+	const char *string;
+
+	/* print the controller name */
+	seq_printf(m, "   Host scsi%d: usb-storage\n", host->host_no);
+
+	/* print product, vendor, and serial number strings */
+	if (us->pusb_dev->manufacturer)
+		string = us->pusb_dev->manufacturer;
+	else if (us->unusual_dev->vendorName)
+		string = us->unusual_dev->vendorName;
+	else
+		string = "Unknown";
+	seq_printf(m, "       Vendor: %s\n", string);
+	if (us->pusb_dev->product)
+		string = us->pusb_dev->product;
+	else if (us->unusual_dev->productName)
+		string = us->unusual_dev->productName;
+	else
+		string = "Unknown";
+	seq_printf(m, "      Product: %s\n", string);
+	if (us->pusb_dev->serial)
+		string = us->pusb_dev->serial;
+	else
+		string = "None";
+	seq_printf(m, "Serial Number: %s\n", string);
+
+	/* show the protocol and transport */
+	seq_printf(m, "     Protocol: %s\n", us->protocol_name);
+	seq_printf(m, "    Transport: %s\n", us->transport_name);
+
+	/* show the device flags */
+	seq_printf(m, "       Quirks:");
+
+#define US_FLAG(name, value) \
+	if (us->fflags & value) seq_printf(m, " " #name);
+US_DO_ALL_FLAGS
+#undef US_FLAG
+	seq_putc(m, '\n');
+	return 0;
+}
+
+/***********************************************************************
+ * Sysfs interface
+ ***********************************************************************/
+
+/* Output routine for the sysfs max_sectors file */
+static ssize_t max_sectors_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+
+	return sprintf(buf, "%u\n", queue_max_hw_sectors(sdev->request_queue));
+}
+
+/* Input routine for the sysfs max_sectors file */
+static ssize_t max_sectors_store(struct device *dev, struct device_attribute *attr, const char *buf,
+		size_t count)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	unsigned short ms;
+
+	if (sscanf(buf, "%hu", &ms) > 0) {
+		blk_queue_max_hw_sectors(sdev->request_queue, ms);
+		return count;
+	}
+	return -EINVAL;
+}
+static DEVICE_ATTR_RW(max_sectors);
+
+static struct device_attribute *sysfs_device_attr_list[] = {
+	&dev_attr_max_sectors,
+	NULL,
+};
+
+/*
+ * this defines our host template, with which we'll allocate hosts
+ */
+
+static const struct scsi_host_template usb_stor_host_template = {
+	/* basic userland interface stuff */
+	.name =				"usb-storage",
+	.proc_name =			"usb-storage",
+	.show_info =			show_info,
+	.write_info =			write_info,
+	.info =				host_info,
+
+	/* command interface -- queued only */
+	.queuecommand =			queuecommand,
+
+	/* error and abort handlers */
+	.eh_abort_handler =		command_abort,
+	.eh_device_reset_handler =	device_reset,
+	.eh_bus_reset_handler =		bus_reset,
+
+	/* queue commands only, only one command per LUN */
+	.can_queue =			1,
+
+	/* unknown initiator id */
+	.this_id =			-1,
+
+	.slave_alloc =			slave_alloc,
+	.slave_configure =		slave_configure,
+	.target_alloc =			target_alloc,
+
+	/* lots of sg segments can be handled */
+	.sg_tablesize =			SCSI_MAX_SG_CHAIN_SEGMENTS,
+
+	/* limit the total size of a transfer to 120 KB */
+	.max_sectors =                  240,
+
+	/* merge commands... this seems to help performance, but
+	 * periodically someone should test to see which setting is more
+	 * optimal.
+	 */
+	.use_clustering =		1,
+
+	/* emulated HBA */
+	.emulated =			1,
+
+	/* we do our own delay after a device or bus reset */
+	.skip_settle_delay =		1,
+
+	/* sysfs device attributes */
+	.sdev_attrs =			sysfs_device_attr_list,
+
+	/* module management */
+	.module =			THIS_MODULE
+};
+
+void usb_stor_host_template_init(struct scsi_host_template *sht,
+				 const char *name, struct module *owner)
+{
+	*sht = usb_stor_host_template;
+	sht->name = name;
+	sht->proc_name = name;
+	sht->module = owner;
+}
+EXPORT_SYMBOL_GPL(usb_stor_host_template_init);
+
+/* To Report "Illegal Request: Invalid Field in CDB */
+unsigned char usb_stor_sense_invalidCDB[18] = {
+	[0]	= 0x70,			    /* current error */
+	[2]	= ILLEGAL_REQUEST,	    /* Illegal Request = 0x05 */
+	[7]	= 0x0a,			    /* additional length */
+	[12]	= 0x24			    /* Invalid Field in CDB */
+};
+EXPORT_SYMBOL_GPL(usb_stor_sense_invalidCDB);