1 files changed, 500 insertions, 0 deletions
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
new file mode 100644
index 00000000000..22e48a2b0bd
--- /dev/null
+++ b/drivers/usb/storage/scsiglue.c
@@ -0,0 +1,500 @@
+/* Driver for USB Mass Storage compliant devices
+ * SCSI layer glue code
+ *
+ * $Id: scsiglue.c,v 1.26 2002/04/22 03:39:43 mdharm Exp $
+ *
+ * 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/slab.h>
+#include <linux/module.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"
+
+/***********************************************************************
+ * Host functions 
+ ***********************************************************************/
+
+static const char* host_info(struct Scsi_Host *host)
+{
+	return "SCSI emulation for USB Mass Storage devices";
+}
+
+static int slave_alloc (struct scsi_device *sdev)
+{
+	/*
+	 * 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;
+	return 0;
+}
+
+static int slave_configure(struct scsi_device *sdev)
+{
+	struct us_data *us = host_to_us(sdev->host);
+
+	/* Scatter-gather buffers (all but the last) must have a length
+	 * divisible by the bulk maxpacket size.  Otherwise a data packet
+	 * would end up being short, causing a premature end to the data
+	 * transfer.  Since high-speed bulk pipes have a maxpacket size
+	 * of 512, we'll use that as the scsi device queue's DMA alignment
+	 * mask.  Guaranteeing proper alignment of the first buffer will
+	 * have the desired effect because, except at the beginning and
+	 * the end, scatter-gather buffers follow page boundaries. */
+	blk_queue_dma_alignment(sdev->request_queue, (512 - 1));
+
+	/* Set the SCSI level to at least 2.  We'll leave it at 3 if that's
+	 * what is originally reported.  We need this to avoid confusing
+	 * the SCSI layer with devices that report 0 or 1, but need 10-byte
+	 * commands (ala ATAPI devices behind certain bridges, or devices
+	 * which simply have broken INQUIRY data).
+	 *
+	 * NOTE: This means /dev/sg programs (ala cdrecord) will get the
+	 * actual information.  This seems to be the preference for
+	 * programs like that.
+	 *
+	 * NOTE: This also means that /proc/scsi/scsi and sysfs may report
+	 * the actual value or the modified one, depending on where the
+	 * data comes from.
+	 */
+	if (sdev->scsi_level < SCSI_2)
+		sdev->scsi_level = SCSI_2;
+
+	/* According to the technical support people at Genesys Logic,
+	 * devices using their chips have problems transferring more than
+	 * 32 KB at a time.  In practice people have found that 64 KB
+	 * works okay and that's what Windows does.  But we'll be
+	 * conservative; people can always use the sysfs interface to
+	 * increase max_sectors. */
+	if (le16_to_cpu(us->pusb_dev->descriptor.idVendor) == USB_VENDOR_ID_GENESYS &&
+			sdev->request_queue->max_sectors > 64)
+		blk_queue_max_sectors(sdev->request_queue, 64);
+
+	/* 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) {
+
+		/* Disk-type devices use MODE SENSE(6) if the protocol
+		 * (SubClass) is Transparent SCSI, otherwise they use
+		 * MODE SENSE(10). */
+		if (us->subclass != US_SC_SCSI)
+			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->flags & 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 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->flags & US_FL_FIX_CAPACITY)
+			sdev->fix_capacity = 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 devices choke when they receive a PREVENT-ALLOW MEDIUM
+	 * REMOVAL command, so suppress those commands. */
+	if (us->flags & 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;
+}
+
+/* queue a command */
+/* This is always called with scsi_lock(host) held */
+static int queuecommand(struct scsi_cmnd *srb,
+			void (*done)(struct scsi_cmnd *))
+{
+	struct us_data *us = host_to_us(srb->device->host);
+
+	US_DEBUGP("%s called\n", __FUNCTION__);
+
+	/* check for state-transition errors */
+	if (us->srb != NULL) {
+		printk(KERN_ERR USB_STORAGE "Error in %s: us->srb = %p\n",
+			__FUNCTION__, us->srb);
+		return SCSI_MLQUEUE_HOST_BUSY;
+	}
+
+	/* fail the command if we are disconnecting */
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+		US_DEBUGP("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;
+	up(&(us->sema));
+
+	return 0;
+}
+
+/***********************************************************************
+ * Error handling functions
+ ***********************************************************************/
+
+/* Command timeout and abort */
+/* This is always called with scsi_lock(host) held */
+static int command_abort(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+
+	US_DEBUGP("%s called\n", __FUNCTION__);
+
+	/* Is this command still active? */
+	if (us->srb != srb) {
+		US_DEBUGP ("-- 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).  To prevent races with auto-reset, we must
+	 * stop any ongoing USB transfers while still holding the host
+	 * lock. */
+	set_bit(US_FLIDX_TIMED_OUT, &us->flags);
+	if (!test_bit(US_FLIDX_RESETTING, &us->flags)) {
+		set_bit(US_FLIDX_ABORTING, &us->flags);
+		usb_stor_stop_transport(us);
+	}
+	scsi_unlock(us_to_host(us));
+
+	/* Wait for the aborted command to finish */
+	wait_for_completion(&us->notify);
+
+	/* Reacquire the lock and allow USB transfers to resume */
+	scsi_lock(us_to_host(us));
+	clear_bit(US_FLIDX_ABORTING, &us->flags);
+	clear_bit(US_FLIDX_TIMED_OUT, &us->flags);
+	return SUCCESS;
+}
+
+/* This invokes the transport reset mechanism to reset the state of the
+ * device */
+/* This is always called with scsi_lock(host) held */
+static int device_reset(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+	int result;
+
+	US_DEBUGP("%s called\n", __FUNCTION__);
+
+	scsi_unlock(us_to_host(us));
+
+	/* lock the device pointers and do the reset */
+	down(&(us->dev_semaphore));
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+		result = FAILED;
+		US_DEBUGP("No reset during disconnect\n");
+	} else
+		result = us->transport_reset(us);
+	up(&(us->dev_semaphore));
+
+	/* lock the host for the return */
+	scsi_lock(us_to_host(us));
+	return result;
+}
+
+/* This resets the device's USB port. */
+/* It refuses to work if there's more than one interface in
+ * the device, so that other users are not affected. */
+/* This is always called with scsi_lock(host) held */
+static int bus_reset(struct scsi_cmnd *srb)
+{
+	struct us_data *us = host_to_us(srb->device->host);
+	int result, rc;
+
+	US_DEBUGP("%s called\n", __FUNCTION__);
+
+	scsi_unlock(us_to_host(us));
+
+	/* The USB subsystem doesn't handle synchronisation between
+	 * a device's several drivers. Therefore we reset only devices
+	 * with just one interface, which we of course own. */
+
+	down(&(us->dev_semaphore));
+	if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+		result = -EIO;
+		US_DEBUGP("No reset during disconnect\n");
+	} else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) {
+		result = -EBUSY;
+		US_DEBUGP("Refusing to reset a multi-interface device\n");
+	} else {
+		rc = usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
+		if (rc < 0) {
+			US_DEBUGP("unable to lock device for reset: %d\n", rc);
+			result = rc;
+		} else {
+			result = usb_reset_device(us->pusb_dev);
+			if (rc)
+				usb_unlock_device(us->pusb_dev);
+			US_DEBUGP("usb_reset_device returns %d\n", result);
+		}
+	}
+	up(&(us->dev_semaphore));
+
+	/* lock the host for the return */
+	scsi_lock(us_to_host(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->flags & US_FL_SCM_MULT_TARG) {
+		for (i = 1; i < host->max_id; ++i)
+			scsi_report_device_reset(host, 0, i);
+	}
+}
+
+/***********************************************************************
+ * /proc/scsi/ functions
+ ***********************************************************************/
+
+/* we use this macro to help us write into the buffer */
+#undef SPRINTF
+#define SPRINTF(args...) \
+	do { if (pos < buffer+length) pos += sprintf(pos, ## args); } while (0)
+
+static int proc_info (struct Scsi_Host *host, char *buffer,
+		char **start, off_t offset, int length, int inout)
+{
+	struct us_data *us = host_to_us(host);
+	char *pos = buffer;
+	const char *string;
+
+	/* if someone is sending us data, just throw it away */
+	if (inout)
+		return length;
+
+	/* print the controller name */
+	SPRINTF("   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";
+	SPRINTF("       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";
+	SPRINTF("      Product: %s\n", string);
+	if (us->pusb_dev->serial)
+		string = us->pusb_dev->serial;
+	else
+		string = "None";
+	SPRINTF("Serial Number: %s\n", string);
+
+	/* show the protocol and transport */
+	SPRINTF("     Protocol: %s\n", us->protocol_name);
+	SPRINTF("    Transport: %s\n", us->transport_name);
+
+	/* show the device flags */
+	if (pos < buffer + length) {
+		pos += sprintf(pos, "       Quirks:");
+
+#define US_FLAG(name, value) \
+	if (us->flags & value) pos += sprintf(pos, " " #name);
+US_DO_ALL_FLAGS
+#undef US_FLAG
+
+		*(pos++) = '\n';
+	}
+
+	/*
+	 * Calculate start of next buffer, and return value.
+	 */
+	*start = buffer + offset;
+
+	if ((pos - buffer) < offset)
+		return (0);
+	else if ((pos - buffer - offset) < length)
+		return (pos - buffer - offset);
+	else
+		return (length);
+}
+
+/***********************************************************************
+ * Sysfs interface
+ ***********************************************************************/
+
+/* Output routine for the sysfs max_sectors file */
+static ssize_t show_max_sectors(struct device *dev, char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+
+	return sprintf(buf, "%u\n", sdev->request_queue->max_sectors);
+}
+
+/* Input routine for the sysfs max_sectors file */
+static ssize_t store_max_sectors(struct device *dev, const char *buf,
+		size_t count)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	unsigned short ms;
+
+	if (sscanf(buf, "%hu", &ms) > 0 && ms <= SCSI_DEFAULT_MAX_SECTORS) {
+		blk_queue_max_sectors(sdev->request_queue, ms);
+		return strlen(buf);
+	}
+	return -EINVAL;	
+}
+
+static DEVICE_ATTR(max_sectors, S_IRUGO | S_IWUSR, show_max_sectors,
+		store_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
+ */
+
+struct scsi_host_template usb_stor_host_template = {
+	/* basic userland interface stuff */
+	.name =				"usb-storage",
+	.proc_name =			"usb-storage",
+	.proc_info =			proc_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,
+	.cmd_per_lun =			1,
+
+	/* unknown initiator id */
+	.this_id =			-1,
+
+	.slave_alloc =			slave_alloc,
+	.slave_configure =		slave_configure,
+
+	/* lots of sg segments can be handled */
+	.sg_tablesize =			SG_ALL,
+
+	/* 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
+};
+
+/* 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 */
+};
+