usb: gadget: Gadget directory cleanup - group usb functions

The drivers/usb/gadget directory contains many files.
Files which are related can be distributed into separate directories.
This patch moves the USB functions implementations into a separate directory.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 0 insertions, 3668 deletions

diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
deleted file mode 100644
index b96393908860..000000000000
--- a/drivers/usb/gadget/f_mass_storage.c
+++ /dev/null
@@ -1,3668 +0,0 @@
-/*
- * f_mass_storage.c -- Mass Storage USB Composite Function
- *
- * Copyright (C) 2003-2008 Alan Stern
- * Copyright (C) 2009 Samsung Electronics
- *                    Author: Michal Nazarewicz <mina86@mina86.com>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions, and the following disclaimer,
- *    without modification.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. The names of the above-listed copyright holders may not be used
- *    to endorse or promote products derived from this software without
- *    specific prior written permission.
- *
- * ALTERNATIVELY, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") as published by the Free Software
- * Foundation, either version 2 of that License or (at your option) any
- * later version.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
- * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-/*
- * The Mass Storage Function acts as a USB Mass Storage device,
- * appearing to the host as a disk drive or as a CD-ROM drive.  In
- * addition to providing an example of a genuinely useful composite
- * function for a USB device, it also illustrates a technique of
- * double-buffering for increased throughput.
- *
- * For more information about MSF and in particular its module
- * parameters and sysfs interface read the
- * <Documentation/usb/mass-storage.txt> file.
- */
-
-/*
- * MSF is configured by specifying a fsg_config structure.  It has the
- * following fields:
- *
- *	nluns		Number of LUNs function have (anywhere from 1
- *				to FSG_MAX_LUNS which is 8).
- *	luns		An array of LUN configuration values.  This
- *				should be filled for each LUN that
- *				function will include (ie. for "nluns"
- *				LUNs).  Each element of the array has
- *				the following fields:
- *	->filename	The path to the backing file for the LUN.
- *				Required if LUN is not marked as
- *				removable.
- *	->ro		Flag specifying access to the LUN shall be
- *				read-only.  This is implied if CD-ROM
- *				emulation is enabled as well as when
- *				it was impossible to open "filename"
- *				in R/W mode.
- *	->removable	Flag specifying that LUN shall be indicated as
- *				being removable.
- *	->cdrom		Flag specifying that LUN shall be reported as
- *				being a CD-ROM.
- *	->nofua		Flag specifying that FUA flag in SCSI WRITE(10,12)
- *				commands for this LUN shall be ignored.
- *
- *	vendor_name
- *	product_name
- *	release		Information used as a reply to INQUIRY
- *				request.  To use default set to NULL,
- *				NULL, 0xffff respectively.  The first
- *				field should be 8 and the second 16
- *				characters or less.
- *
- *	can_stall	Set to permit function to halt bulk endpoints.
- *				Disabled on some USB devices known not
- *				to work correctly.  You should set it
- *				to true.
- *
- * If "removable" is not set for a LUN then a backing file must be
- * specified.  If it is set, then NULL filename means the LUN's medium
- * is not loaded (an empty string as "filename" in the fsg_config
- * structure causes error).  The CD-ROM emulation includes a single
- * data track and no audio tracks; hence there need be only one
- * backing file per LUN.
- *
- * This function is heavily based on "File-backed Storage Gadget" by
- * Alan Stern which in turn is heavily based on "Gadget Zero" by David
- * Brownell.  The driver's SCSI command interface was based on the
- * "Information technology - Small Computer System Interface - 2"
- * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
- * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
- * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
- * was based on the "Universal Serial Bus Mass Storage Class UFI
- * Command Specification" document, Revision 1.0, December 14, 1998,
- * available at
- * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
- */
-
-/*
- *				Driver Design
- *
- * The MSF is fairly straightforward.  There is a main kernel
- * thread that handles most of the work.  Interrupt routines field
- * callbacks from the controller driver: bulk- and interrupt-request
- * completion notifications, endpoint-0 events, and disconnect events.
- * Completion events are passed to the main thread by wakeup calls.  Many
- * ep0 requests are handled at interrupt time, but SetInterface,
- * SetConfiguration, and device reset requests are forwarded to the
- * thread in the form of "exceptions" using SIGUSR1 signals (since they
- * should interrupt any ongoing file I/O operations).
- *
- * The thread's main routine implements the standard command/data/status
- * parts of a SCSI interaction.  It and its subroutines are full of tests
- * for pending signals/exceptions -- all this polling is necessary since
- * the kernel has no setjmp/longjmp equivalents.  (Maybe this is an
- * indication that the driver really wants to be running in userspace.)
- * An important point is that so long as the thread is alive it keeps an
- * open reference to the backing file.  This will prevent unmounting
- * the backing file's underlying filesystem and could cause problems
- * during system shutdown, for example.  To prevent such problems, the
- * thread catches INT, TERM, and KILL signals and converts them into
- * an EXIT exception.
- *
- * In normal operation the main thread is started during the gadget's
- * fsg_bind() callback and stopped during fsg_unbind().  But it can
- * also exit when it receives a signal, and there's no point leaving
- * the gadget running when the thread is dead.  As of this moment, MSF
- * provides no way to deregister the gadget when thread dies -- maybe
- * a callback functions is needed.
- *
- * To provide maximum throughput, the driver uses a circular pipeline of
- * buffer heads (struct fsg_buffhd).  In principle the pipeline can be
- * arbitrarily long; in practice the benefits don't justify having more
- * than 2 stages (i.e., double buffering).  But it helps to think of the
- * pipeline as being a long one.  Each buffer head contains a bulk-in and
- * a bulk-out request pointer (since the buffer can be used for both
- * output and input -- directions always are given from the host's
- * point of view) as well as a pointer to the buffer and various state
- * variables.
- *
- * Use of the pipeline follows a simple protocol.  There is a variable
- * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
- * At any time that buffer head may still be in use from an earlier
- * request, so each buffer head has a state variable indicating whether
- * it is EMPTY, FULL, or BUSY.  Typical use involves waiting for the
- * buffer head to be EMPTY, filling the buffer either by file I/O or by
- * USB I/O (during which the buffer head is BUSY), and marking the buffer
- * head FULL when the I/O is complete.  Then the buffer will be emptied
- * (again possibly by USB I/O, during which it is marked BUSY) and
- * finally marked EMPTY again (possibly by a completion routine).
- *
- * A module parameter tells the driver to avoid stalling the bulk
- * endpoints wherever the transport specification allows.  This is
- * necessary for some UDCs like the SuperH, which cannot reliably clear a
- * halt on a bulk endpoint.  However, under certain circumstances the
- * Bulk-only specification requires a stall.  In such cases the driver
- * will halt the endpoint and set a flag indicating that it should clear
- * the halt in software during the next device reset.  Hopefully this
- * will permit everything to work correctly.  Furthermore, although the
- * specification allows the bulk-out endpoint to halt when the host sends
- * too much data, implementing this would cause an unavoidable race.
- * The driver will always use the "no-stall" approach for OUT transfers.
- *
- * One subtle point concerns sending status-stage responses for ep0
- * requests.  Some of these requests, such as device reset, can involve
- * interrupting an ongoing file I/O operation, which might take an
- * arbitrarily long time.  During that delay the host might give up on
- * the original ep0 request and issue a new one.  When that happens the
- * driver should not notify the host about completion of the original
- * request, as the host will no longer be waiting for it.  So the driver
- * assigns to each ep0 request a unique tag, and it keeps track of the
- * tag value of the request associated with a long-running exception
- * (device-reset, interface-change, or configuration-change).  When the
- * exception handler is finished, the status-stage response is submitted
- * only if the current ep0 request tag is equal to the exception request
- * tag.  Thus only the most recently received ep0 request will get a
- * status-stage response.
- *
- * Warning: This driver source file is too long.  It ought to be split up
- * into a header file plus about 3 separate .c files, to handle the details
- * of the Gadget, USB Mass Storage, and SCSI protocols.
- */
-
-
-/* #define VERBOSE_DEBUG */
-/* #define DUMP_MSGS */
-
-#include <linux/blkdev.h>
-#include <linux/completion.h>
-#include <linux/dcache.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/fcntl.h>
-#include <linux/file.h>
-#include <linux/fs.h>
-#include <linux/kref.h>
-#include <linux/kthread.h>
-#include <linux/limits.h>
-#include <linux/rwsem.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/string.h>
-#include <linux/freezer.h>
-#include <linux/module.h>
-
-#include <linux/usb/ch9.h>
-#include <linux/usb/gadget.h>
-#include <linux/usb/composite.h>
-
-#include "gadget_chips.h"
-#include "configfs.h"
-
-
-/*------------------------------------------------------------------------*/
-
-#define FSG_DRIVER_DESC		"Mass Storage Function"
-#define FSG_DRIVER_VERSION	"2009/09/11"
-
-static const char fsg_string_interface[] = "Mass Storage";
-
-#include "storage_common.h"
-#include "f_mass_storage.h"
-
-/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
-static struct usb_string		fsg_strings[] = {
-	{FSG_STRING_INTERFACE,		fsg_string_interface},
-	{}
-};
-
-static struct usb_gadget_strings	fsg_stringtab = {
-	.language	= 0x0409,		/* en-us */
-	.strings	= fsg_strings,
-};
-
-static struct usb_gadget_strings *fsg_strings_array[] = {
-	&fsg_stringtab,
-	NULL,
-};
-
-/*-------------------------------------------------------------------------*/
-
-struct fsg_dev;
-struct fsg_common;
-
-/* Data shared by all the FSG instances. */
-struct fsg_common {
-	struct usb_gadget	*gadget;
-	struct usb_composite_dev *cdev;
-	struct fsg_dev		*fsg, *new_fsg;
-	wait_queue_head_t	fsg_wait;
-
-	/* filesem protects: backing files in use */
-	struct rw_semaphore	filesem;
-
-	/* lock protects: state, all the req_busy's */
-	spinlock_t		lock;
-
-	struct usb_ep		*ep0;		/* Copy of gadget->ep0 */
-	struct usb_request	*ep0req;	/* Copy of cdev->req */
-	unsigned int		ep0_req_tag;
-
-	struct fsg_buffhd	*next_buffhd_to_fill;
-	struct fsg_buffhd	*next_buffhd_to_drain;
-	struct fsg_buffhd	*buffhds;
-	unsigned int		fsg_num_buffers;
-
-	int			cmnd_size;
-	u8			cmnd[MAX_COMMAND_SIZE];
-
-	unsigned int		nluns;
-	unsigned int		lun;
-	struct fsg_lun		**luns;
-	struct fsg_lun		*curlun;
-
-	unsigned int		bulk_out_maxpacket;
-	enum fsg_state		state;		/* For exception handling */
-	unsigned int		exception_req_tag;
-
-	enum data_direction	data_dir;
-	u32			data_size;
-	u32			data_size_from_cmnd;
-	u32			tag;
-	u32			residue;
-	u32			usb_amount_left;
-
-	unsigned int		can_stall:1;
-	unsigned int		free_storage_on_release:1;
-	unsigned int		phase_error:1;
-	unsigned int		short_packet_received:1;
-	unsigned int		bad_lun_okay:1;
-	unsigned int		running:1;
-	unsigned int		sysfs:1;
-
-	int			thread_wakeup_needed;
-	struct completion	thread_notifier;
-	struct task_struct	*thread_task;
-
-	/* Callback functions. */
-	const struct fsg_operations	*ops;
-	/* Gadget's private data. */
-	void			*private_data;
-
-	/*
-	 * Vendor (8 chars), product (16 chars), release (4
-	 * hexadecimal digits) and NUL byte
-	 */
-	char inquiry_string[8 + 16 + 4 + 1];
-
-	struct kref		ref;
-};
-
-struct fsg_dev {
-	struct usb_function	function;
-	struct usb_gadget	*gadget;	/* Copy of cdev->gadget */
-	struct fsg_common	*common;
-
-	u16			interface_number;
-
-	unsigned int		bulk_in_enabled:1;
-	unsigned int		bulk_out_enabled:1;
-
-	unsigned long		atomic_bitflags;
-#define IGNORE_BULK_OUT		0
-
-	struct usb_ep		*bulk_in;
-	struct usb_ep		*bulk_out;
-};
-
-static inline int __fsg_is_set(struct fsg_common *common,
-			       const char *func, unsigned line)
-{
-	if (common->fsg)
-		return 1;
-	ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
-	WARN_ON(1);
-	return 0;
-}
-
-#define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
-
-static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
-{
-	return container_of(f, struct fsg_dev, function);
-}
-
-typedef void (*fsg_routine_t)(struct fsg_dev *);
-
-static int exception_in_progress(struct fsg_common *common)
-{
-	return common->state > FSG_STATE_IDLE;
-}
-
-/* Make bulk-out requests be divisible by the maxpacket size */
-static void set_bulk_out_req_length(struct fsg_common *common,
-				    struct fsg_buffhd *bh, unsigned int length)
-{
-	unsigned int	rem;
-
-	bh->bulk_out_intended_length = length;
-	rem = length % common->bulk_out_maxpacket;
-	if (rem > 0)
-		length += common->bulk_out_maxpacket - rem;
-	bh->outreq->length = length;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
-{
-	const char	*name;
-
-	if (ep == fsg->bulk_in)
-		name = "bulk-in";
-	else if (ep == fsg->bulk_out)
-		name = "bulk-out";
-	else
-		name = ep->name;
-	DBG(fsg, "%s set halt\n", name);
-	return usb_ep_set_halt(ep);
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-/* These routines may be called in process context or in_irq */
-
-/* Caller must hold fsg->lock */
-static void wakeup_thread(struct fsg_common *common)
-{
-	smp_wmb();	/* ensure the write of bh->state is complete */
-	/* Tell the main thread that something has happened */
-	common->thread_wakeup_needed = 1;
-	if (common->thread_task)
-		wake_up_process(common->thread_task);
-}
-
-static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
-{
-	unsigned long		flags;
-
-	/*
-	 * Do nothing if a higher-priority exception is already in progress.
-	 * If a lower-or-equal priority exception is in progress, preempt it
-	 * and notify the main thread by sending it a signal.
-	 */
-	spin_lock_irqsave(&common->lock, flags);
-	if (common->state <= new_state) {
-		common->exception_req_tag = common->ep0_req_tag;
-		common->state = new_state;
-		if (common->thread_task)
-			send_sig_info(SIGUSR1, SEND_SIG_FORCED,
-				      common->thread_task);
-	}
-	spin_unlock_irqrestore(&common->lock, flags);
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int ep0_queue(struct fsg_common *common)
-{
-	int	rc;
-
-	rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
-	common->ep0->driver_data = common;
-	if (rc != 0 && rc != -ESHUTDOWN) {
-		/* We can't do much more than wait for a reset */
-		WARNING(common, "error in submission: %s --> %d\n",
-			common->ep0->name, rc);
-	}
-	return rc;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-/* Completion handlers. These always run in_irq. */
-
-static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct fsg_common	*common = ep->driver_data;
-	struct fsg_buffhd	*bh = req->context;
-
-	if (req->status || req->actual != req->length)
-		DBG(common, "%s --> %d, %u/%u\n", __func__,
-		    req->status, req->actual, req->length);
-	if (req->status == -ECONNRESET)		/* Request was cancelled */
-		usb_ep_fifo_flush(ep);
-
-	/* Hold the lock while we update the request and buffer states */
-	smp_wmb();
-	spin_lock(&common->lock);
-	bh->inreq_busy = 0;
-	bh->state = BUF_STATE_EMPTY;
-	wakeup_thread(common);
-	spin_unlock(&common->lock);
-}
-
-static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
-{
-	struct fsg_common	*common = ep->driver_data;
-	struct fsg_buffhd	*bh = req->context;
-
-	dump_msg(common, "bulk-out", req->buf, req->actual);
-	if (req->status || req->actual != bh->bulk_out_intended_length)
-		DBG(common, "%s --> %d, %u/%u\n", __func__,
-		    req->status, req->actual, bh->bulk_out_intended_length);
-	if (req->status == -ECONNRESET)		/* Request was cancelled */
-		usb_ep_fifo_flush(ep);
-
-	/* Hold the lock while we update the request and buffer states */
-	smp_wmb();
-	spin_lock(&common->lock);
-	bh->outreq_busy = 0;
-	bh->state = BUF_STATE_FULL;
-	wakeup_thread(common);
-	spin_unlock(&common->lock);
-}
-
-static int fsg_setup(struct usb_function *f,
-		     const struct usb_ctrlrequest *ctrl)
-{
-	struct fsg_dev		*fsg = fsg_from_func(f);
-	struct usb_request	*req = fsg->common->ep0req;
-	u16			w_index = le16_to_cpu(ctrl->wIndex);
-	u16			w_value = le16_to_cpu(ctrl->wValue);
-	u16			w_length = le16_to_cpu(ctrl->wLength);
-
-	if (!fsg_is_set(fsg->common))
-		return -EOPNOTSUPP;
-
-	++fsg->common->ep0_req_tag;	/* Record arrival of a new request */
-	req->context = NULL;
-	req->length = 0;
-	dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
-
-	switch (ctrl->bRequest) {
-
-	case US_BULK_RESET_REQUEST:
-		if (ctrl->bRequestType !=
-		    (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
-			break;
-		if (w_index != fsg->interface_number || w_value != 0 ||
-				w_length != 0)
-			return -EDOM;
-
-		/*
-		 * Raise an exception to stop the current operation
-		 * and reinitialize our state.
-		 */
-		DBG(fsg, "bulk reset request\n");
-		raise_exception(fsg->common, FSG_STATE_RESET);
-		return USB_GADGET_DELAYED_STATUS;
-
-	case US_BULK_GET_MAX_LUN:
-		if (ctrl->bRequestType !=
-		    (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
-			break;
-		if (w_index != fsg->interface_number || w_value != 0 ||
-				w_length != 1)
-			return -EDOM;
-		VDBG(fsg, "get max LUN\n");
-		*(u8 *)req->buf = fsg->common->nluns - 1;
-
-		/* Respond with data/status */
-		req->length = min((u16)1, w_length);
-		return ep0_queue(fsg->common);
-	}
-
-	VDBG(fsg,
-	     "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
-	     ctrl->bRequestType, ctrl->bRequest,
-	     le16_to_cpu(ctrl->wValue), w_index, w_length);
-	return -EOPNOTSUPP;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-/* All the following routines run in process context */
-
-/* Use this for bulk or interrupt transfers, not ep0 */
-static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
-			   struct usb_request *req, int *pbusy,
-			   enum fsg_buffer_state *state)
-{
-	int	rc;
-
-	if (ep == fsg->bulk_in)
-		dump_msg(fsg, "bulk-in", req->buf, req->length);
-
-	spin_lock_irq(&fsg->common->lock);
-	*pbusy = 1;
-	*state = BUF_STATE_BUSY;
-	spin_unlock_irq(&fsg->common->lock);
-	rc = usb_ep_queue(ep, req, GFP_KERNEL);
-	if (rc != 0) {
-		*pbusy = 0;
-		*state = BUF_STATE_EMPTY;
-
-		/* We can't do much more than wait for a reset */
-
-		/*
-		 * Note: currently the net2280 driver fails zero-length
-		 * submissions if DMA is enabled.
-		 */
-		if (rc != -ESHUTDOWN &&
-		    !(rc == -EOPNOTSUPP && req->length == 0))
-			WARNING(fsg, "error in submission: %s --> %d\n",
-				ep->name, rc);
-	}
-}
-
-static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	if (!fsg_is_set(common))
-		return false;
-	start_transfer(common->fsg, common->fsg->bulk_in,
-		       bh->inreq, &bh->inreq_busy, &bh->state);
-	return true;
-}
-
-static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	if (!fsg_is_set(common))
-		return false;
-	start_transfer(common->fsg, common->fsg->bulk_out,
-		       bh->outreq, &bh->outreq_busy, &bh->state);
-	return true;
-}
-
-static int sleep_thread(struct fsg_common *common, bool can_freeze)
-{
-	int	rc = 0;
-
-	/* Wait until a signal arrives or we are woken up */
-	for (;;) {
-		if (can_freeze)
-			try_to_freeze();
-		set_current_state(TASK_INTERRUPTIBLE);
-		if (signal_pending(current)) {
-			rc = -EINTR;
-			break;
-		}
-		if (common->thread_wakeup_needed)
-			break;
-		schedule();
-	}
-	__set_current_state(TASK_RUNNING);
-	common->thread_wakeup_needed = 0;
-	smp_rmb();	/* ensure the latest bh->state is visible */
-	return rc;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int do_read(struct fsg_common *common)
-{
-	struct fsg_lun		*curlun = common->curlun;
-	u32			lba;
-	struct fsg_buffhd	*bh;
-	int			rc;
-	u32			amount_left;
-	loff_t			file_offset, file_offset_tmp;
-	unsigned int		amount;
-	ssize_t			nread;
-
-	/*
-	 * Get the starting Logical Block Address and check that it's
-	 * not too big.
-	 */
-	if (common->cmnd[0] == READ_6)
-		lba = get_unaligned_be24(&common->cmnd[1]);
-	else {
-		lba = get_unaligned_be32(&common->cmnd[2]);
-
-		/*
-		 * We allow DPO (Disable Page Out = don't save data in the
-		 * cache) and FUA (Force Unit Access = don't read from the
-		 * cache), but we don't implement them.
-		 */
-		if ((common->cmnd[1] & ~0x18) != 0) {
-			curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-			return -EINVAL;
-		}
-	}
-	if (lba >= curlun->num_sectors) {
-		curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-		return -EINVAL;
-	}
-	file_offset = ((loff_t) lba) << curlun->blkbits;
-
-	/* Carry out the file reads */
-	amount_left = common->data_size_from_cmnd;
-	if (unlikely(amount_left == 0))
-		return -EIO;		/* No default reply */
-
-	for (;;) {
-		/*
-		 * Figure out how much we need to read:
-		 * Try to read the remaining amount.
-		 * But don't read more than the buffer size.
-		 * And don't try to read past the end of the file.
-		 */
-		amount = min(amount_left, FSG_BUFLEN);
-		amount = min((loff_t)amount,
-			     curlun->file_length - file_offset);
-
-		/* Wait for the next buffer to become available */
-		bh = common->next_buffhd_to_fill;
-		while (bh->state != BUF_STATE_EMPTY) {
-			rc = sleep_thread(common, false);
-			if (rc)
-				return rc;
-		}
-
-		/*
-		 * If we were asked to read past the end of file,
-		 * end with an empty buffer.
-		 */
-		if (amount == 0) {
-			curlun->sense_data =
-					SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-			curlun->sense_data_info =
-					file_offset >> curlun->blkbits;
-			curlun->info_valid = 1;
-			bh->inreq->length = 0;
-			bh->state = BUF_STATE_FULL;
-			break;
-		}
-
-		/* Perform the read */
-		file_offset_tmp = file_offset;
-		nread = vfs_read(curlun->filp,
-				 (char __user *)bh->buf,
-				 amount, &file_offset_tmp);
-		VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
-		      (unsigned long long)file_offset, (int)nread);
-		if (signal_pending(current))
-			return -EINTR;
-
-		if (nread < 0) {
-			LDBG(curlun, "error in file read: %d\n", (int)nread);
-			nread = 0;
-		} else if (nread < amount) {
-			LDBG(curlun, "partial file read: %d/%u\n",
-			     (int)nread, amount);
-			nread = round_down(nread, curlun->blksize);
-		}
-		file_offset  += nread;
-		amount_left  -= nread;
-		common->residue -= nread;
-
-		/*
-		 * Except at the end of the transfer, nread will be
-		 * equal to the buffer size, which is divisible by the
-		 * bulk-in maxpacket size.
-		 */
-		bh->inreq->length = nread;
-		bh->state = BUF_STATE_FULL;
-
-		/* If an error occurred, report it and its position */
-		if (nread < amount) {
-			curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
-			curlun->sense_data_info =
-					file_offset >> curlun->blkbits;
-			curlun->info_valid = 1;
-			break;
-		}
-
-		if (amount_left == 0)
-			break;		/* No more left to read */
-
-		/* Send this buffer and go read some more */
-		bh->inreq->zero = 0;
-		if (!start_in_transfer(common, bh))
-			/* Don't know what to do if common->fsg is NULL */
-			return -EIO;
-		common->next_buffhd_to_fill = bh->next;
-	}
-
-	return -EIO;		/* No default reply */
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int do_write(struct fsg_common *common)
-{
-	struct fsg_lun		*curlun = common->curlun;
-	u32			lba;
-	struct fsg_buffhd	*bh;
-	int			get_some_more;
-	u32			amount_left_to_req, amount_left_to_write;
-	loff_t			usb_offset, file_offset, file_offset_tmp;
-	unsigned int		amount;
-	ssize_t			nwritten;
-	int			rc;
-
-	if (curlun->ro) {
-		curlun->sense_data = SS_WRITE_PROTECTED;
-		return -EINVAL;
-	}
-	spin_lock(&curlun->filp->f_lock);
-	curlun->filp->f_flags &= ~O_SYNC;	/* Default is not to wait */
-	spin_unlock(&curlun->filp->f_lock);
-
-	/*
-	 * Get the starting Logical Block Address and check that it's
-	 * not too big
-	 */
-	if (common->cmnd[0] == WRITE_6)
-		lba = get_unaligned_be24(&common->cmnd[1]);
-	else {
-		lba = get_unaligned_be32(&common->cmnd[2]);
-
-		/*
-		 * We allow DPO (Disable Page Out = don't save data in the
-		 * cache) and FUA (Force Unit Access = write directly to the
-		 * medium).  We don't implement DPO; we implement FUA by
-		 * performing synchronous output.
-		 */
-		if (common->cmnd[1] & ~0x18) {
-			curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-			return -EINVAL;
-		}
-		if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
-			spin_lock(&curlun->filp->f_lock);
-			curlun->filp->f_flags |= O_SYNC;
-			spin_unlock(&curlun->filp->f_lock);
-		}
-	}
-	if (lba >= curlun->num_sectors) {
-		curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-		return -EINVAL;
-	}
-
-	/* Carry out the file writes */
-	get_some_more = 1;
-	file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
-	amount_left_to_req = common->data_size_from_cmnd;
-	amount_left_to_write = common->data_size_from_cmnd;
-
-	while (amount_left_to_write > 0) {
-
-		/* Queue a request for more data from the host */
-		bh = common->next_buffhd_to_fill;
-		if (bh->state == BUF_STATE_EMPTY && get_some_more) {
-
-			/*
-			 * Figure out how much we want to get:
-			 * Try to get the remaining amount,
-			 * but not more than the buffer size.
-			 */
-			amount = min(amount_left_to_req, FSG_BUFLEN);
-
-			/* Beyond the end of the backing file? */
-			if (usb_offset >= curlun->file_length) {
-				get_some_more = 0;
-				curlun->sense_data =
-					SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-				curlun->sense_data_info =
-					usb_offset >> curlun->blkbits;
-				curlun->info_valid = 1;
-				continue;
-			}
-
-			/* Get the next buffer */
-			usb_offset += amount;
-			common->usb_amount_left -= amount;
-			amount_left_to_req -= amount;
-			if (amount_left_to_req == 0)
-				get_some_more = 0;
-
-			/*
-			 * Except at the end of the transfer, amount will be
-			 * equal to the buffer size, which is divisible by
-			 * the bulk-out maxpacket size.
-			 */
-			set_bulk_out_req_length(common, bh, amount);
-			if (!start_out_transfer(common, bh))
-				/* Dunno what to do if common->fsg is NULL */
-				return -EIO;
-			common->next_buffhd_to_fill = bh->next;
-			continue;
-		}
-
-		/* Write the received data to the backing file */
-		bh = common->next_buffhd_to_drain;
-		if (bh->state == BUF_STATE_EMPTY && !get_some_more)
-			break;			/* We stopped early */
-		if (bh->state == BUF_STATE_FULL) {
-			smp_rmb();
-			common->next_buffhd_to_drain = bh->next;
-			bh->state = BUF_STATE_EMPTY;
-
-			/* Did something go wrong with the transfer? */
-			if (bh->outreq->status != 0) {
-				curlun->sense_data = SS_COMMUNICATION_FAILURE;
-				curlun->sense_data_info =
-					file_offset >> curlun->blkbits;
-				curlun->info_valid = 1;
-				break;
-			}
-
-			amount = bh->outreq->actual;
-			if (curlun->file_length - file_offset < amount) {
-				LERROR(curlun,
-				       "write %u @ %llu beyond end %llu\n",
-				       amount, (unsigned long long)file_offset,
-				       (unsigned long long)curlun->file_length);
-				amount = curlun->file_length - file_offset;
-			}
-
-			/* Don't accept excess data.  The spec doesn't say
-			 * what to do in this case.  We'll ignore the error.
-			 */
-			amount = min(amount, bh->bulk_out_intended_length);
-
-			/* Don't write a partial block */
-			amount = round_down(amount, curlun->blksize);
-			if (amount == 0)
-				goto empty_write;
-
-			/* Perform the write */
-			file_offset_tmp = file_offset;
-			nwritten = vfs_write(curlun->filp,
-					     (char __user *)bh->buf,
-					     amount, &file_offset_tmp);
-			VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
-			      (unsigned long long)file_offset, (int)nwritten);
-			if (signal_pending(current))
-				return -EINTR;		/* Interrupted! */
-
-			if (nwritten < 0) {
-				LDBG(curlun, "error in file write: %d\n",
-				     (int)nwritten);
-				nwritten = 0;
-			} else if (nwritten < amount) {
-				LDBG(curlun, "partial file write: %d/%u\n",
-				     (int)nwritten, amount);
-				nwritten = round_down(nwritten, curlun->blksize);
-			}
-			file_offset += nwritten;
-			amount_left_to_write -= nwritten;
-			common->residue -= nwritten;
-
-			/* If an error occurred, report it and its position */
-			if (nwritten < amount) {
-				curlun->sense_data = SS_WRITE_ERROR;
-				curlun->sense_data_info =
-					file_offset >> curlun->blkbits;
-				curlun->info_valid = 1;
-				break;
-			}
-
- empty_write:
-			/* Did the host decide to stop early? */
-			if (bh->outreq->actual < bh->bulk_out_intended_length) {
-				common->short_packet_received = 1;
-				break;
-			}
-			continue;
-		}
-
-		/* Wait for something to happen */
-		rc = sleep_thread(common, false);
-		if (rc)
-			return rc;
-	}
-
-	return -EIO;		/* No default reply */
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int do_synchronize_cache(struct fsg_common *common)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		rc;
-
-	/* We ignore the requested LBA and write out all file's
-	 * dirty data buffers. */
-	rc = fsg_lun_fsync_sub(curlun);
-	if (rc)
-		curlun->sense_data = SS_WRITE_ERROR;
-	return 0;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static void invalidate_sub(struct fsg_lun *curlun)
-{
-	struct file	*filp = curlun->filp;
-	struct inode	*inode = file_inode(filp);
-	unsigned long	rc;
-
-	rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
-	VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
-}
-
-static int do_verify(struct fsg_common *common)
-{
-	struct fsg_lun		*curlun = common->curlun;
-	u32			lba;
-	u32			verification_length;
-	struct fsg_buffhd	*bh = common->next_buffhd_to_fill;
-	loff_t			file_offset, file_offset_tmp;
-	u32			amount_left;
-	unsigned int		amount;
-	ssize_t			nread;
-
-	/*
-	 * Get the starting Logical Block Address and check that it's
-	 * not too big.
-	 */
-	lba = get_unaligned_be32(&common->cmnd[2]);
-	if (lba >= curlun->num_sectors) {
-		curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-		return -EINVAL;
-	}
-
-	/*
-	 * We allow DPO (Disable Page Out = don't save data in the
-	 * cache) but we don't implement it.
-	 */
-	if (common->cmnd[1] & ~0x10) {
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	verification_length = get_unaligned_be16(&common->cmnd[7]);
-	if (unlikely(verification_length == 0))
-		return -EIO;		/* No default reply */
-
-	/* Prepare to carry out the file verify */
-	amount_left = verification_length << curlun->blkbits;
-	file_offset = ((loff_t) lba) << curlun->blkbits;
-
-	/* Write out all the dirty buffers before invalidating them */
-	fsg_lun_fsync_sub(curlun);
-	if (signal_pending(current))
-		return -EINTR;
-
-	invalidate_sub(curlun);
-	if (signal_pending(current))
-		return -EINTR;
-
-	/* Just try to read the requested blocks */
-	while (amount_left > 0) {
-		/*
-		 * Figure out how much we need to read:
-		 * Try to read the remaining amount, but not more than
-		 * the buffer size.
-		 * And don't try to read past the end of the file.
-		 */
-		amount = min(amount_left, FSG_BUFLEN);
-		amount = min((loff_t)amount,
-			     curlun->file_length - file_offset);
-		if (amount == 0) {
-			curlun->sense_data =
-					SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-			curlun->sense_data_info =
-				file_offset >> curlun->blkbits;
-			curlun->info_valid = 1;
-			break;
-		}
-
-		/* Perform the read */
-		file_offset_tmp = file_offset;
-		nread = vfs_read(curlun->filp,
-				(char __user *) bh->buf,
-				amount, &file_offset_tmp);
-		VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
-				(unsigned long long) file_offset,
-				(int) nread);
-		if (signal_pending(current))
-			return -EINTR;
-
-		if (nread < 0) {
-			LDBG(curlun, "error in file verify: %d\n", (int)nread);
-			nread = 0;
-		} else if (nread < amount) {
-			LDBG(curlun, "partial file verify: %d/%u\n",
-			     (int)nread, amount);
-			nread = round_down(nread, curlun->blksize);
-		}
-		if (nread == 0) {
-			curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
-			curlun->sense_data_info =
-				file_offset >> curlun->blkbits;
-			curlun->info_valid = 1;
-			break;
-		}
-		file_offset += nread;
-		amount_left -= nread;
-	}
-	return 0;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun *curlun = common->curlun;
-	u8	*buf = (u8 *) bh->buf;
-
-	if (!curlun) {		/* Unsupported LUNs are okay */
-		common->bad_lun_okay = 1;
-		memset(buf, 0, 36);
-		buf[0] = 0x7f;		/* Unsupported, no device-type */
-		buf[4] = 31;		/* Additional length */
-		return 36;
-	}
-
-	buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
-	buf[1] = curlun->removable ? 0x80 : 0;
-	buf[2] = 2;		/* ANSI SCSI level 2 */
-	buf[3] = 2;		/* SCSI-2 INQUIRY data format */
-	buf[4] = 31;		/* Additional length */
-	buf[5] = 0;		/* No special options */
-	buf[6] = 0;
-	buf[7] = 0;
-	memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
-	return 36;
-}
-
-static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	u8		*buf = (u8 *) bh->buf;
-	u32		sd, sdinfo;
-	int		valid;
-
-	/*
-	 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
-	 *
-	 * If a REQUEST SENSE command is received from an initiator
-	 * with a pending unit attention condition (before the target
-	 * generates the contingent allegiance condition), then the
-	 * target shall either:
-	 *   a) report any pending sense data and preserve the unit
-	 *	attention condition on the logical unit, or,
-	 *   b) report the unit attention condition, may discard any
-	 *	pending sense data, and clear the unit attention
-	 *	condition on the logical unit for that initiator.
-	 *
-	 * FSG normally uses option a); enable this code to use option b).
-	 */
-#if 0
-	if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
-		curlun->sense_data = curlun->unit_attention_data;
-		curlun->unit_attention_data = SS_NO_SENSE;
-	}
-#endif
-
-	if (!curlun) {		/* Unsupported LUNs are okay */
-		common->bad_lun_okay = 1;
-		sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
-		sdinfo = 0;
-		valid = 0;
-	} else {
-		sd = curlun->sense_data;
-		sdinfo = curlun->sense_data_info;
-		valid = curlun->info_valid << 7;
-		curlun->sense_data = SS_NO_SENSE;
-		curlun->sense_data_info = 0;
-		curlun->info_valid = 0;
-	}
-
-	memset(buf, 0, 18);
-	buf[0] = valid | 0x70;			/* Valid, current error */
-	buf[2] = SK(sd);
-	put_unaligned_be32(sdinfo, &buf[3]);	/* Sense information */
-	buf[7] = 18 - 8;			/* Additional sense length */
-	buf[12] = ASC(sd);
-	buf[13] = ASCQ(sd);
-	return 18;
-}
-
-static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	u32		lba = get_unaligned_be32(&common->cmnd[2]);
-	int		pmi = common->cmnd[8];
-	u8		*buf = (u8 *)bh->buf;
-
-	/* Check the PMI and LBA fields */
-	if (pmi > 1 || (pmi == 0 && lba != 0)) {
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
-						/* Max logical block */
-	put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
-	return 8;
-}
-
-static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		msf = common->cmnd[1] & 0x02;
-	u32		lba = get_unaligned_be32(&common->cmnd[2]);
-	u8		*buf = (u8 *)bh->buf;
-
-	if (common->cmnd[1] & ~0x02) {		/* Mask away MSF */
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-	if (lba >= curlun->num_sectors) {
-		curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
-		return -EINVAL;
-	}
-
-	memset(buf, 0, 8);
-	buf[0] = 0x01;		/* 2048 bytes of user data, rest is EC */
-	store_cdrom_address(&buf[4], msf, lba);
-	return 8;
-}
-
-static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		msf = common->cmnd[1] & 0x02;
-	int		start_track = common->cmnd[6];
-	u8		*buf = (u8 *)bh->buf;
-
-	if ((common->cmnd[1] & ~0x02) != 0 ||	/* Mask away MSF */
-			start_track > 1) {
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	memset(buf, 0, 20);
-	buf[1] = (20-2);		/* TOC data length */
-	buf[2] = 1;			/* First track number */
-	buf[3] = 1;			/* Last track number */
-	buf[5] = 0x16;			/* Data track, copying allowed */
-	buf[6] = 0x01;			/* Only track is number 1 */
-	store_cdrom_address(&buf[8], msf, 0);
-
-	buf[13] = 0x16;			/* Lead-out track is data */
-	buf[14] = 0xAA;			/* Lead-out track number */
-	store_cdrom_address(&buf[16], msf, curlun->num_sectors);
-	return 20;
-}
-
-static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		mscmnd = common->cmnd[0];
-	u8		*buf = (u8 *) bh->buf;
-	u8		*buf0 = buf;
-	int		pc, page_code;
-	int		changeable_values, all_pages;
-	int		valid_page = 0;
-	int		len, limit;
-
-	if ((common->cmnd[1] & ~0x08) != 0) {	/* Mask away DBD */
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-	pc = common->cmnd[2] >> 6;
-	page_code = common->cmnd[2] & 0x3f;
-	if (pc == 3) {
-		curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
-		return -EINVAL;
-	}
-	changeable_values = (pc == 1);
-	all_pages = (page_code == 0x3f);
-
-	/*
-	 * Write the mode parameter header.  Fixed values are: default
-	 * medium type, no cache control (DPOFUA), and no block descriptors.
-	 * The only variable value is the WriteProtect bit.  We will fill in
-	 * the mode data length later.
-	 */
-	memset(buf, 0, 8);
-	if (mscmnd == MODE_SENSE) {
-		buf[2] = (curlun->ro ? 0x80 : 0x00);		/* WP, DPOFUA */
-		buf += 4;
-		limit = 255;
-	} else {			/* MODE_SENSE_10 */
-		buf[3] = (curlun->ro ? 0x80 : 0x00);		/* WP, DPOFUA */
-		buf += 8;
-		limit = 65535;		/* Should really be FSG_BUFLEN */
-	}
-
-	/* No block descriptors */
-
-	/*
-	 * The mode pages, in numerical order.  The only page we support
-	 * is the Caching page.
-	 */
-	if (page_code == 0x08 || all_pages) {
-		valid_page = 1;
-		buf[0] = 0x08;		/* Page code */
-		buf[1] = 10;		/* Page length */
-		memset(buf+2, 0, 10);	/* None of the fields are changeable */
-
-		if (!changeable_values) {
-			buf[2] = 0x04;	/* Write cache enable, */
-					/* Read cache not disabled */
-					/* No cache retention priorities */
-			put_unaligned_be16(0xffff, &buf[4]);
-					/* Don't disable prefetch */
-					/* Minimum prefetch = 0 */
-			put_unaligned_be16(0xffff, &buf[8]);
-					/* Maximum prefetch */
-			put_unaligned_be16(0xffff, &buf[10]);
-					/* Maximum prefetch ceiling */
-		}
-		buf += 12;
-	}
-
-	/*
-	 * Check that a valid page was requested and the mode data length
-	 * isn't too long.
-	 */
-	len = buf - buf0;
-	if (!valid_page || len > limit) {
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	/*  Store the mode data length */
-	if (mscmnd == MODE_SENSE)
-		buf0[0] = len - 1;
-	else
-		put_unaligned_be16(len - 2, buf0);
-	return len;
-}
-
-static int do_start_stop(struct fsg_common *common)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		loej, start;
-
-	if (!curlun) {
-		return -EINVAL;
-	} else if (!curlun->removable) {
-		curlun->sense_data = SS_INVALID_COMMAND;
-		return -EINVAL;
-	} else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
-		   (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	loej  = common->cmnd[4] & 0x02;
-	start = common->cmnd[4] & 0x01;
-
-	/*
-	 * Our emulation doesn't support mounting; the medium is
-	 * available for use as soon as it is loaded.
-	 */
-	if (start) {
-		if (!fsg_lun_is_open(curlun)) {
-			curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
-			return -EINVAL;
-		}
-		return 0;
-	}
-
-	/* Are we allowed to unload the media? */
-	if (curlun->prevent_medium_removal) {
-		LDBG(curlun, "unload attempt prevented\n");
-		curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
-		return -EINVAL;
-	}
-
-	if (!loej)
-		return 0;
-
-	up_read(&common->filesem);
-	down_write(&common->filesem);
-	fsg_lun_close(curlun);
-	up_write(&common->filesem);
-	down_read(&common->filesem);
-
-	return 0;
-}
-
-static int do_prevent_allow(struct fsg_common *common)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	int		prevent;
-
-	if (!common->curlun) {
-		return -EINVAL;
-	} else if (!common->curlun->removable) {
-		common->curlun->sense_data = SS_INVALID_COMMAND;
-		return -EINVAL;
-	}
-
-	prevent = common->cmnd[4] & 0x01;
-	if ((common->cmnd[4] & ~0x01) != 0) {	/* Mask away Prevent */
-		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-		return -EINVAL;
-	}
-
-	if (curlun->prevent_medium_removal && !prevent)
-		fsg_lun_fsync_sub(curlun);
-	curlun->prevent_medium_removal = prevent;
-	return 0;
-}
-
-static int do_read_format_capacities(struct fsg_common *common,
-			struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-	u8		*buf = (u8 *) bh->buf;
-
-	buf[0] = buf[1] = buf[2] = 0;
-	buf[3] = 8;	/* Only the Current/Maximum Capacity Descriptor */
-	buf += 4;
-
-	put_unaligned_be32(curlun->num_sectors, &buf[0]);
-						/* Number of blocks */
-	put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
-	buf[4] = 0x02;				/* Current capacity */
-	return 12;
-}
-
-static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
-{
-	struct fsg_lun	*curlun = common->curlun;
-
-	/* We don't support MODE SELECT */
-	if (curlun)
-		curlun->sense_data = SS_INVALID_COMMAND;
-	return -EINVAL;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
-{
-	int	rc;
-
-	rc = fsg_set_halt(fsg, fsg->bulk_in);
-	if (rc == -EAGAIN)
-		VDBG(fsg, "delayed bulk-in endpoint halt\n");
-	while (rc != 0) {
-		if (rc != -EAGAIN) {
-			WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
-			rc = 0;
-			break;
-		}
-
-		/* Wait for a short time and then try again */
-		if (msleep_interruptible(100) != 0)
-			return -EINTR;
-		rc = usb_ep_set_halt(fsg->bulk_in);
-	}
-	return rc;
-}
-
-static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
-{
-	int	rc;
-
-	DBG(fsg, "bulk-in set wedge\n");
-	rc = usb_ep_set_wedge(fsg->bulk_in);
-	if (rc == -EAGAIN)
-		VDBG(fsg, "delayed bulk-in endpoint wedge\n");
-	while (rc != 0) {
-		if (rc != -EAGAIN) {
-			WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
-			rc = 0;
-			break;
-		}
-
-		/* Wait for a short time and then try again */
-		if (msleep_interruptible(100) != 0)
-			return -EINTR;
-		rc = usb_ep_set_wedge(fsg->bulk_in);
-	}
-	return rc;
-}
-
-static int throw_away_data(struct fsg_common *common)
-{
-	struct fsg_buffhd	*bh;
-	u32			amount;
-	int			rc;
-
-	for (bh = common->next_buffhd_to_drain;
-	     bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
-	     bh = common->next_buffhd_to_drain) {
-
-		/* Throw away the data in a filled buffer */
-		if (bh->state == BUF_STATE_FULL) {
-			smp_rmb();
-			bh->state = BUF_STATE_EMPTY;
-			common->next_buffhd_to_drain = bh->next;
-
-			/* A short packet or an error ends everything */
-			if (bh->outreq->actual < bh->bulk_out_intended_length ||
-			    bh->outreq->status != 0) {
-				raise_exception(common,
-						FSG_STATE_ABORT_BULK_OUT);
-				return -EINTR;
-			}
-			continue;
-		}
-
-		/* Try to submit another request if we need one */
-		bh = common->next_buffhd_to_fill;
-		if (bh->state == BUF_STATE_EMPTY
-		 && common->usb_amount_left > 0) {
-			amount = min(common->usb_amount_left, FSG_BUFLEN);
-
-			/*
-			 * Except at the end of the transfer, amount will be
-			 * equal to the buffer size, which is divisible by
-			 * the bulk-out maxpacket size.
-			 */
-			set_bulk_out_req_length(common, bh, amount);
-			if (!start_out_transfer(common, bh))
-				/* Dunno what to do if common->fsg is NULL */
-				return -EIO;
-			common->next_buffhd_to_fill = bh->next;
-			common->usb_amount_left -= amount;
-			continue;
-		}
-
-		/* Otherwise wait for something to happen */
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-	return 0;
-}
-
-static int finish_reply(struct fsg_common *common)
-{
-	struct fsg_buffhd	*bh = common->next_buffhd_to_fill;
-	int			rc = 0;
-
-	switch (common->data_dir) {
-	case DATA_DIR_NONE:
-		break;			/* Nothing to send */
-
-	/*
-	 * If we don't know whether the host wants to read or write,
-	 * this must be CB or CBI with an unknown command.  We mustn't
-	 * try to send or receive any data.  So stall both bulk pipes
-	 * if we can and wait for a reset.
-	 */
-	case DATA_DIR_UNKNOWN:
-		if (!common->can_stall) {
-			/* Nothing */
-		} else if (fsg_is_set(common)) {
-			fsg_set_halt(common->fsg, common->fsg->bulk_out);
-			rc = halt_bulk_in_endpoint(common->fsg);
-		} else {
-			/* Don't know what to do if common->fsg is NULL */
-			rc = -EIO;
-		}
-		break;
-
-	/* All but the last buffer of data must have already been sent */
-	case DATA_DIR_TO_HOST:
-		if (common->data_size == 0) {
-			/* Nothing to send */
-
-		/* Don't know what to do if common->fsg is NULL */
-		} else if (!fsg_is_set(common)) {
-			rc = -EIO;
-
-		/* If there's no residue, simply send the last buffer */
-		} else if (common->residue == 0) {
-			bh->inreq->zero = 0;
-			if (!start_in_transfer(common, bh))
-				return -EIO;
-			common->next_buffhd_to_fill = bh->next;
-
-		/*
-		 * For Bulk-only, mark the end of the data with a short
-		 * packet.  If we are allowed to stall, halt the bulk-in
-		 * endpoint.  (Note: This violates the Bulk-Only Transport
-		 * specification, which requires us to pad the data if we
-		 * don't halt the endpoint.  Presumably nobody will mind.)
-		 */
-		} else {
-			bh->inreq->zero = 1;
-			if (!start_in_transfer(common, bh))
-				rc = -EIO;
-			common->next_buffhd_to_fill = bh->next;
-			if (common->can_stall)
-				rc = halt_bulk_in_endpoint(common->fsg);
-		}
-		break;
-
-	/*
-	 * We have processed all we want from the data the host has sent.
-	 * There may still be outstanding bulk-out requests.
-	 */
-	case DATA_DIR_FROM_HOST:
-		if (common->residue == 0) {
-			/* Nothing to receive */
-
-		/* Did the host stop sending unexpectedly early? */
-		} else if (common->short_packet_received) {
-			raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
-			rc = -EINTR;
-
-		/*
-		 * We haven't processed all the incoming data.  Even though
-		 * we may be allowed to stall, doing so would cause a race.
-		 * The controller may already have ACK'ed all the remaining
-		 * bulk-out packets, in which case the host wouldn't see a
-		 * STALL.  Not realizing the endpoint was halted, it wouldn't
-		 * clear the halt -- leading to problems later on.
-		 */
-#if 0
-		} else if (common->can_stall) {
-			if (fsg_is_set(common))
-				fsg_set_halt(common->fsg,
-					     common->fsg->bulk_out);
-			raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
-			rc = -EINTR;
-#endif
-
-		/*
-		 * We can't stall.  Read in the excess data and throw it
-		 * all away.
-		 */
-		} else {
-			rc = throw_away_data(common);
-		}
-		break;
-	}
-	return rc;
-}
-
-static int send_status(struct fsg_common *common)
-{
-	struct fsg_lun		*curlun = common->curlun;
-	struct fsg_buffhd	*bh;
-	struct bulk_cs_wrap	*csw;
-	int			rc;
-	u8			status = US_BULK_STAT_OK;
-	u32			sd, sdinfo = 0;
-
-	/* Wait for the next buffer to become available */
-	bh = common->next_buffhd_to_fill;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-
-	if (curlun) {
-		sd = curlun->sense_data;
-		sdinfo = curlun->sense_data_info;
-	} else if (common->bad_lun_okay)
-		sd = SS_NO_SENSE;
-	else
-		sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
-
-	if (common->phase_error) {
-		DBG(common, "sending phase-error status\n");
-		status = US_BULK_STAT_PHASE;
-		sd = SS_INVALID_COMMAND;
-	} else if (sd != SS_NO_SENSE) {
-		DBG(common, "sending command-failure status\n");
-		status = US_BULK_STAT_FAIL;
-		VDBG(common, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
-				"  info x%x\n",
-				SK(sd), ASC(sd), ASCQ(sd), sdinfo);
-	}
-
-	/* Store and send the Bulk-only CSW */
-	csw = (void *)bh->buf;
-
-	csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
-	csw->Tag = common->tag;
-	csw->Residue = cpu_to_le32(common->residue);
-	csw->Status = status;
-
-	bh->inreq->length = US_BULK_CS_WRAP_LEN;
-	bh->inreq->zero = 0;
-	if (!start_in_transfer(common, bh))
-		/* Don't know what to do if common->fsg is NULL */
-		return -EIO;
-
-	common->next_buffhd_to_fill = bh->next;
-	return 0;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-/*
- * Check whether the command is properly formed and whether its data size
- * and direction agree with the values we already have.
- */
-static int check_command(struct fsg_common *common, int cmnd_size,
-			 enum data_direction data_dir, unsigned int mask,
-			 int needs_medium, const char *name)
-{
-	int			i;
-	unsigned int		lun = common->cmnd[1] >> 5;
-	static const char	dirletter[4] = {'u', 'o', 'i', 'n'};
-	char			hdlen[20];
-	struct fsg_lun		*curlun;
-
-	hdlen[0] = 0;
-	if (common->data_dir != DATA_DIR_UNKNOWN)
-		sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
-			common->data_size);
-	VDBG(common, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
-	     name, cmnd_size, dirletter[(int) data_dir],
-	     common->data_size_from_cmnd, common->cmnd_size, hdlen);
-
-	/*
-	 * We can't reply at all until we know the correct data direction
-	 * and size.
-	 */
-	if (common->data_size_from_cmnd == 0)
-		data_dir = DATA_DIR_NONE;
-	if (common->data_size < common->data_size_from_cmnd) {
-		/*
-		 * Host data size < Device data size is a phase error.
-		 * Carry out the command, but only transfer as much as
-		 * we are allowed.
-		 */
-		common->data_size_from_cmnd = common->data_size;
-		common->phase_error = 1;
-	}
-	common->residue = common->data_size;
-	common->usb_amount_left = common->data_size;
-
-	/* Conflicting data directions is a phase error */
-	if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
-		common->phase_error = 1;
-		return -EINVAL;
-	}
-
-	/* Verify the length of the command itself */
-	if (cmnd_size != common->cmnd_size) {
-
-		/*
-		 * Special case workaround: There are plenty of buggy SCSI
-		 * implementations. Many have issues with cbw->Length
-		 * field passing a wrong command size. For those cases we
-		 * always try to work around the problem by using the length
-		 * sent by the host side provided it is at least as large
-		 * as the correct command length.
-		 * Examples of such cases would be MS-Windows, which issues
-		 * REQUEST SENSE with cbw->Length == 12 where it should
-		 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
-		 * REQUEST SENSE with cbw->Length == 10 where it should
-		 * be 6 as well.
-		 */
-		if (cmnd_size <= common->cmnd_size) {
-			DBG(common, "%s is buggy! Expected length %d "
-			    "but we got %d\n", name,
-			    cmnd_size, common->cmnd_size);
-			cmnd_size = common->cmnd_size;
-		} else {
-			common->phase_error = 1;
-			return -EINVAL;
-		}
-	}
-
-	/* Check that the LUN values are consistent */
-	if (common->lun != lun)
-		DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
-		    common->lun, lun);
-
-	/* Check the LUN */
-	curlun = common->curlun;
-	if (curlun) {
-		if (common->cmnd[0] != REQUEST_SENSE) {
-			curlun->sense_data = SS_NO_SENSE;
-			curlun->sense_data_info = 0;
-			curlun->info_valid = 0;
-		}
-	} else {
-		common->bad_lun_okay = 0;
-
-		/*
-		 * INQUIRY and REQUEST SENSE commands are explicitly allowed
-		 * to use unsupported LUNs; all others may not.
-		 */
-		if (common->cmnd[0] != INQUIRY &&
-		    common->cmnd[0] != REQUEST_SENSE) {
-			DBG(common, "unsupported LUN %u\n", common->lun);
-			return -EINVAL;
-		}
-	}
-
-	/*
-	 * If a unit attention condition exists, only INQUIRY and
-	 * REQUEST SENSE commands are allowed; anything else must fail.
-	 */
-	if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
-	    common->cmnd[0] != INQUIRY &&
-	    common->cmnd[0] != REQUEST_SENSE) {
-		curlun->sense_data = curlun->unit_attention_data;
-		curlun->unit_attention_data = SS_NO_SENSE;
-		return -EINVAL;
-	}
-
-	/* Check that only command bytes listed in the mask are non-zero */
-	common->cmnd[1] &= 0x1f;			/* Mask away the LUN */
-	for (i = 1; i < cmnd_size; ++i) {
-		if (common->cmnd[i] && !(mask & (1 << i))) {
-			if (curlun)
-				curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
-			return -EINVAL;
-		}
-	}
-
-	/* If the medium isn't mounted and the command needs to access
-	 * it, return an error. */
-	if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
-		curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-/* wrapper of check_command for data size in blocks handling */
-static int check_command_size_in_blocks(struct fsg_common *common,
-		int cmnd_size, enum data_direction data_dir,
-		unsigned int mask, int needs_medium, const char *name)
-{
-	if (common->curlun)
-		common->data_size_from_cmnd <<= common->curlun->blkbits;
-	return check_command(common, cmnd_size, data_dir,
-			mask, needs_medium, name);
-}
-
-static int do_scsi_command(struct fsg_common *common)
-{
-	struct fsg_buffhd	*bh;
-	int			rc;
-	int			reply = -EINVAL;
-	int			i;
-	static char		unknown[16];
-
-	dump_cdb(common);
-
-	/* Wait for the next buffer to become available for data or status */
-	bh = common->next_buffhd_to_fill;
-	common->next_buffhd_to_drain = bh;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-	common->phase_error = 0;
-	common->short_packet_received = 0;
-
-	down_read(&common->filesem);	/* We're using the backing file */
-	switch (common->cmnd[0]) {
-
-	case INQUIRY:
-		common->data_size_from_cmnd = common->cmnd[4];
-		reply = check_command(common, 6, DATA_DIR_TO_HOST,
-				      (1<<4), 0,
-				      "INQUIRY");
-		if (reply == 0)
-			reply = do_inquiry(common, bh);
-		break;
-
-	case MODE_SELECT:
-		common->data_size_from_cmnd = common->cmnd[4];
-		reply = check_command(common, 6, DATA_DIR_FROM_HOST,
-				      (1<<1) | (1<<4), 0,
-				      "MODE SELECT(6)");
-		if (reply == 0)
-			reply = do_mode_select(common, bh);
-		break;
-
-	case MODE_SELECT_10:
-		common->data_size_from_cmnd =
-			get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command(common, 10, DATA_DIR_FROM_HOST,
-				      (1<<1) | (3<<7), 0,
-				      "MODE SELECT(10)");
-		if (reply == 0)
-			reply = do_mode_select(common, bh);
-		break;
-
-	case MODE_SENSE:
-		common->data_size_from_cmnd = common->cmnd[4];
-		reply = check_command(common, 6, DATA_DIR_TO_HOST,
-				      (1<<1) | (1<<2) | (1<<4), 0,
-				      "MODE SENSE(6)");
-		if (reply == 0)
-			reply = do_mode_sense(common, bh);
-		break;
-
-	case MODE_SENSE_10:
-		common->data_size_from_cmnd =
-			get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command(common, 10, DATA_DIR_TO_HOST,
-				      (1<<1) | (1<<2) | (3<<7), 0,
-				      "MODE SENSE(10)");
-		if (reply == 0)
-			reply = do_mode_sense(common, bh);
-		break;
-
-	case ALLOW_MEDIUM_REMOVAL:
-		common->data_size_from_cmnd = 0;
-		reply = check_command(common, 6, DATA_DIR_NONE,
-				      (1<<4), 0,
-				      "PREVENT-ALLOW MEDIUM REMOVAL");
-		if (reply == 0)
-			reply = do_prevent_allow(common);
-		break;
-
-	case READ_6:
-		i = common->cmnd[4];
-		common->data_size_from_cmnd = (i == 0) ? 256 : i;
-		reply = check_command_size_in_blocks(common, 6,
-				      DATA_DIR_TO_HOST,
-				      (7<<1) | (1<<4), 1,
-				      "READ(6)");
-		if (reply == 0)
-			reply = do_read(common);
-		break;
-
-	case READ_10:
-		common->data_size_from_cmnd =
-				get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command_size_in_blocks(common, 10,
-				      DATA_DIR_TO_HOST,
-				      (1<<1) | (0xf<<2) | (3<<7), 1,
-				      "READ(10)");
-		if (reply == 0)
-			reply = do_read(common);
-		break;
-
-	case READ_12:
-		common->data_size_from_cmnd =
-				get_unaligned_be32(&common->cmnd[6]);
-		reply = check_command_size_in_blocks(common, 12,
-				      DATA_DIR_TO_HOST,
-				      (1<<1) | (0xf<<2) | (0xf<<6), 1,
-				      "READ(12)");
-		if (reply == 0)
-			reply = do_read(common);
-		break;
-
-	case READ_CAPACITY:
-		common->data_size_from_cmnd = 8;
-		reply = check_command(common, 10, DATA_DIR_TO_HOST,
-				      (0xf<<2) | (1<<8), 1,
-				      "READ CAPACITY");
-		if (reply == 0)
-			reply = do_read_capacity(common, bh);
-		break;
-
-	case READ_HEADER:
-		if (!common->curlun || !common->curlun->cdrom)
-			goto unknown_cmnd;
-		common->data_size_from_cmnd =
-			get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command(common, 10, DATA_DIR_TO_HOST,
-				      (3<<7) | (0x1f<<1), 1,
-				      "READ HEADER");
-		if (reply == 0)
-			reply = do_read_header(common, bh);
-		break;
-
-	case READ_TOC:
-		if (!common->curlun || !common->curlun->cdrom)
-			goto unknown_cmnd;
-		common->data_size_from_cmnd =
-			get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command(common, 10, DATA_DIR_TO_HOST,
-				      (7<<6) | (1<<1), 1,
-				      "READ TOC");
-		if (reply == 0)
-			reply = do_read_toc(common, bh);
-		break;
-
-	case READ_FORMAT_CAPACITIES:
-		common->data_size_from_cmnd =
-			get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command(common, 10, DATA_DIR_TO_HOST,
-				      (3<<7), 1,
-				      "READ FORMAT CAPACITIES");
-		if (reply == 0)
-			reply = do_read_format_capacities(common, bh);
-		break;
-
-	case REQUEST_SENSE:
-		common->data_size_from_cmnd = common->cmnd[4];
-		reply = check_command(common, 6, DATA_DIR_TO_HOST,
-				      (1<<4), 0,
-				      "REQUEST SENSE");
-		if (reply == 0)
-			reply = do_request_sense(common, bh);
-		break;
-
-	case START_STOP:
-		common->data_size_from_cmnd = 0;
-		reply = check_command(common, 6, DATA_DIR_NONE,
-				      (1<<1) | (1<<4), 0,
-				      "START-STOP UNIT");
-		if (reply == 0)
-			reply = do_start_stop(common);
-		break;
-
-	case SYNCHRONIZE_CACHE:
-		common->data_size_from_cmnd = 0;
-		reply = check_command(common, 10, DATA_DIR_NONE,
-				      (0xf<<2) | (3<<7), 1,
-				      "SYNCHRONIZE CACHE");
-		if (reply == 0)
-			reply = do_synchronize_cache(common);
-		break;
-
-	case TEST_UNIT_READY:
-		common->data_size_from_cmnd = 0;
-		reply = check_command(common, 6, DATA_DIR_NONE,
-				0, 1,
-				"TEST UNIT READY");
-		break;
-
-	/*
-	 * Although optional, this command is used by MS-Windows.  We
-	 * support a minimal version: BytChk must be 0.
-	 */
-	case VERIFY:
-		common->data_size_from_cmnd = 0;
-		reply = check_command(common, 10, DATA_DIR_NONE,
-				      (1<<1) | (0xf<<2) | (3<<7), 1,
-				      "VERIFY");
-		if (reply == 0)
-			reply = do_verify(common);
-		break;
-
-	case WRITE_6:
-		i = common->cmnd[4];
-		common->data_size_from_cmnd = (i == 0) ? 256 : i;
-		reply = check_command_size_in_blocks(common, 6,
-				      DATA_DIR_FROM_HOST,
-				      (7<<1) | (1<<4), 1,
-				      "WRITE(6)");
-		if (reply == 0)
-			reply = do_write(common);
-		break;
-
-	case WRITE_10:
-		common->data_size_from_cmnd =
-				get_unaligned_be16(&common->cmnd[7]);
-		reply = check_command_size_in_blocks(common, 10,
-				      DATA_DIR_FROM_HOST,
-				      (1<<1) | (0xf<<2) | (3<<7), 1,
-				      "WRITE(10)");
-		if (reply == 0)
-			reply = do_write(common);
-		break;
-
-	case WRITE_12:
-		common->data_size_from_cmnd =
-				get_unaligned_be32(&common->cmnd[6]);
-		reply = check_command_size_in_blocks(common, 12,
-				      DATA_DIR_FROM_HOST,
-				      (1<<1) | (0xf<<2) | (0xf<<6), 1,
-				      "WRITE(12)");
-		if (reply == 0)
-			reply = do_write(common);
-		break;
-
-	/*
-	 * Some mandatory commands that we recognize but don't implement.
-	 * They don't mean much in this setting.  It's left as an exercise
-	 * for anyone interested to implement RESERVE and RELEASE in terms
-	 * of Posix locks.
-	 */
-	case FORMAT_UNIT:
-	case RELEASE:
-	case RESERVE:
-	case SEND_DIAGNOSTIC:
-		/* Fall through */
-
-	default:
-unknown_cmnd:
-		common->data_size_from_cmnd = 0;
-		sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
-		reply = check_command(common, common->cmnd_size,
-				      DATA_DIR_UNKNOWN, ~0, 0, unknown);
-		if (reply == 0) {
-			common->curlun->sense_data = SS_INVALID_COMMAND;
-			reply = -EINVAL;
-		}
-		break;
-	}
-	up_read(&common->filesem);
-
-	if (reply == -EINTR || signal_pending(current))
-		return -EINTR;
-
-	/* Set up the single reply buffer for finish_reply() */
-	if (reply == -EINVAL)
-		reply = 0;		/* Error reply length */
-	if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
-		reply = min((u32)reply, common->data_size_from_cmnd);
-		bh->inreq->length = reply;
-		bh->state = BUF_STATE_FULL;
-		common->residue -= reply;
-	}				/* Otherwise it's already set */
-
-	return 0;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
-{
-	struct usb_request	*req = bh->outreq;
-	struct bulk_cb_wrap	*cbw = req->buf;
-	struct fsg_common	*common = fsg->common;
-
-	/* Was this a real packet?  Should it be ignored? */
-	if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
-		return -EINVAL;
-
-	/* Is the CBW valid? */
-	if (req->actual != US_BULK_CB_WRAP_LEN ||
-			cbw->Signature != cpu_to_le32(
-				US_BULK_CB_SIGN)) {
-		DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
-				req->actual,
-				le32_to_cpu(cbw->Signature));
-
-		/*
-		 * The Bulk-only spec says we MUST stall the IN endpoint
-		 * (6.6.1), so it's unavoidable.  It also says we must
-		 * retain this state until the next reset, but there's
-		 * no way to tell the controller driver it should ignore
-		 * Clear-Feature(HALT) requests.
-		 *
-		 * We aren't required to halt the OUT endpoint; instead
-		 * we can simply accept and discard any data received
-		 * until the next reset.
-		 */
-		wedge_bulk_in_endpoint(fsg);
-		set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-		return -EINVAL;
-	}
-
-	/* Is the CBW meaningful? */
-	if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
-			cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
-		DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
-				"cmdlen %u\n",
-				cbw->Lun, cbw->Flags, cbw->Length);
-
-		/*
-		 * We can do anything we want here, so let's stall the
-		 * bulk pipes if we are allowed to.
-		 */
-		if (common->can_stall) {
-			fsg_set_halt(fsg, fsg->bulk_out);
-			halt_bulk_in_endpoint(fsg);
-		}
-		return -EINVAL;
-	}
-
-	/* Save the command for later */
-	common->cmnd_size = cbw->Length;
-	memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
-	if (cbw->Flags & US_BULK_FLAG_IN)
-		common->data_dir = DATA_DIR_TO_HOST;
-	else
-		common->data_dir = DATA_DIR_FROM_HOST;
-	common->data_size = le32_to_cpu(cbw->DataTransferLength);
-	if (common->data_size == 0)
-		common->data_dir = DATA_DIR_NONE;
-	common->lun = cbw->Lun;
-	if (common->lun < common->nluns)
-		common->curlun = common->luns[common->lun];
-	else
-		common->curlun = NULL;
-	common->tag = cbw->Tag;
-	return 0;
-}
-
-static int get_next_command(struct fsg_common *common)
-{
-	struct fsg_buffhd	*bh;
-	int			rc = 0;
-
-	/* Wait for the next buffer to become available */
-	bh = common->next_buffhd_to_fill;
-	while (bh->state != BUF_STATE_EMPTY) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-
-	/* Queue a request to read a Bulk-only CBW */
-	set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
-	if (!start_out_transfer(common, bh))
-		/* Don't know what to do if common->fsg is NULL */
-		return -EIO;
-
-	/*
-	 * We will drain the buffer in software, which means we
-	 * can reuse it for the next filling.  No need to advance
-	 * next_buffhd_to_fill.
-	 */
-
-	/* Wait for the CBW to arrive */
-	while (bh->state != BUF_STATE_FULL) {
-		rc = sleep_thread(common, true);
-		if (rc)
-			return rc;
-	}
-	smp_rmb();
-	rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
-	bh->state = BUF_STATE_EMPTY;
-
-	return rc;
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
-		struct usb_request **preq)
-{
-	*preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
-	if (*preq)
-		return 0;
-	ERROR(common, "can't allocate request for %s\n", ep->name);
-	return -ENOMEM;
-}
-
-/* Reset interface setting and re-init endpoint state (toggle etc). */
-static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
-{
-	struct fsg_dev *fsg;
-	int i, rc = 0;
-
-	if (common->running)
-		DBG(common, "reset interface\n");
-
-reset:
-	/* Deallocate the requests */
-	if (common->fsg) {
-		fsg = common->fsg;
-
-		for (i = 0; i < common->fsg_num_buffers; ++i) {
-			struct fsg_buffhd *bh = &common->buffhds[i];
-
-			if (bh->inreq) {
-				usb_ep_free_request(fsg->bulk_in, bh->inreq);
-				bh->inreq = NULL;
-			}
-			if (bh->outreq) {
-				usb_ep_free_request(fsg->bulk_out, bh->outreq);
-				bh->outreq = NULL;
-			}
-		}
-
-		/* Disable the endpoints */
-		if (fsg->bulk_in_enabled) {
-			usb_ep_disable(fsg->bulk_in);
-			fsg->bulk_in->driver_data = NULL;
-			fsg->bulk_in_enabled = 0;
-		}
-		if (fsg->bulk_out_enabled) {
-			usb_ep_disable(fsg->bulk_out);
-			fsg->bulk_out->driver_data = NULL;
-			fsg->bulk_out_enabled = 0;
-		}
-
-		common->fsg = NULL;
-		wake_up(&common->fsg_wait);
-	}
-
-	common->running = 0;
-	if (!new_fsg || rc)
-		return rc;
-
-	common->fsg = new_fsg;
-	fsg = common->fsg;
-
-	/* Enable the endpoints */
-	rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
-	if (rc)
-		goto reset;
-	rc = usb_ep_enable(fsg->bulk_in);
-	if (rc)
-		goto reset;
-	fsg->bulk_in->driver_data = common;
-	fsg->bulk_in_enabled = 1;
-
-	rc = config_ep_by_speed(common->gadget, &(fsg->function),
-				fsg->bulk_out);
-	if (rc)
-		goto reset;
-	rc = usb_ep_enable(fsg->bulk_out);
-	if (rc)
-		goto reset;
-	fsg->bulk_out->driver_data = common;
-	fsg->bulk_out_enabled = 1;
-	common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
-	clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-
-	/* Allocate the requests */
-	for (i = 0; i < common->fsg_num_buffers; ++i) {
-		struct fsg_buffhd	*bh = &common->buffhds[i];
-
-		rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
-		if (rc)
-			goto reset;
-		rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
-		if (rc)
-			goto reset;
-		bh->inreq->buf = bh->outreq->buf = bh->buf;
-		bh->inreq->context = bh->outreq->context = bh;
-		bh->inreq->complete = bulk_in_complete;
-		bh->outreq->complete = bulk_out_complete;
-	}
-
-	common->running = 1;
-	for (i = 0; i < common->nluns; ++i)
-		if (common->luns[i])
-			common->luns[i]->unit_attention_data =
-				SS_RESET_OCCURRED;
-	return rc;
-}
-
-
-/****************************** ALT CONFIGS ******************************/
-
-static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
-{
-	struct fsg_dev *fsg = fsg_from_func(f);
-	fsg->common->new_fsg = fsg;
-	raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
-	return USB_GADGET_DELAYED_STATUS;
-}
-
-static void fsg_disable(struct usb_function *f)
-{
-	struct fsg_dev *fsg = fsg_from_func(f);
-	fsg->common->new_fsg = NULL;
-	raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static void handle_exception(struct fsg_common *common)
-{
-	siginfo_t		info;
-	int			i;
-	struct fsg_buffhd	*bh;
-	enum fsg_state		old_state;
-	struct fsg_lun		*curlun;
-	unsigned int		exception_req_tag;
-
-	/*
-	 * Clear the existing signals.  Anything but SIGUSR1 is converted
-	 * into a high-priority EXIT exception.
-	 */
-	for (;;) {
-		int sig =
-			dequeue_signal_lock(current, &current->blocked, &info);
-		if (!sig)
-			break;
-		if (sig != SIGUSR1) {
-			if (common->state < FSG_STATE_EXIT)
-				DBG(common, "Main thread exiting on signal\n");
-			raise_exception(common, FSG_STATE_EXIT);
-		}
-	}
-
-	/* Cancel all the pending transfers */
-	if (likely(common->fsg)) {
-		for (i = 0; i < common->fsg_num_buffers; ++i) {
-			bh = &common->buffhds[i];
-			if (bh->inreq_busy)
-				usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
-			if (bh->outreq_busy)
-				usb_ep_dequeue(common->fsg->bulk_out,
-					       bh->outreq);
-		}
-
-		/* Wait until everything is idle */
-		for (;;) {
-			int num_active = 0;
-			for (i = 0; i < common->fsg_num_buffers; ++i) {
-				bh = &common->buffhds[i];
-				num_active += bh->inreq_busy + bh->outreq_busy;
-			}
-			if (num_active == 0)
-				break;
-			if (sleep_thread(common, true))
-				return;
-		}
-
-		/* Clear out the controller's fifos */
-		if (common->fsg->bulk_in_enabled)
-			usb_ep_fifo_flush(common->fsg->bulk_in);
-		if (common->fsg->bulk_out_enabled)
-			usb_ep_fifo_flush(common->fsg->bulk_out);
-	}
-
-	/*
-	 * Reset the I/O buffer states and pointers, the SCSI
-	 * state, and the exception.  Then invoke the handler.
-	 */
-	spin_lock_irq(&common->lock);
-
-	for (i = 0; i < common->fsg_num_buffers; ++i) {
-		bh = &common->buffhds[i];
-		bh->state = BUF_STATE_EMPTY;
-	}
-	common->next_buffhd_to_fill = &common->buffhds[0];
-	common->next_buffhd_to_drain = &common->buffhds[0];
-	exception_req_tag = common->exception_req_tag;
-	old_state = common->state;
-
-	if (old_state == FSG_STATE_ABORT_BULK_OUT)
-		common->state = FSG_STATE_STATUS_PHASE;
-	else {
-		for (i = 0; i < common->nluns; ++i) {
-			curlun = common->luns[i];
-			if (!curlun)
-				continue;
-			curlun->prevent_medium_removal = 0;
-			curlun->sense_data = SS_NO_SENSE;
-			curlun->unit_attention_data = SS_NO_SENSE;
-			curlun->sense_data_info = 0;
-			curlun->info_valid = 0;
-		}
-		common->state = FSG_STATE_IDLE;
-	}
-	spin_unlock_irq(&common->lock);
-
-	/* Carry out any extra actions required for the exception */
-	switch (old_state) {
-	case FSG_STATE_ABORT_BULK_OUT:
-		send_status(common);
-		spin_lock_irq(&common->lock);
-		if (common->state == FSG_STATE_STATUS_PHASE)
-			common->state = FSG_STATE_IDLE;
-		spin_unlock_irq(&common->lock);
-		break;
-
-	case FSG_STATE_RESET:
-		/*
-		 * In case we were forced against our will to halt a
-		 * bulk endpoint, clear the halt now.  (The SuperH UDC
-		 * requires this.)
-		 */
-		if (!fsg_is_set(common))
-			break;
-		if (test_and_clear_bit(IGNORE_BULK_OUT,
-				       &common->fsg->atomic_bitflags))
-			usb_ep_clear_halt(common->fsg->bulk_in);
-
-		if (common->ep0_req_tag == exception_req_tag)
-			ep0_queue(common);	/* Complete the status stage */
-
-		/*
-		 * Technically this should go here, but it would only be
-		 * a waste of time.  Ditto for the INTERFACE_CHANGE and
-		 * CONFIG_CHANGE cases.
-		 */
-		/* for (i = 0; i < common->nluns; ++i) */
-		/*	if (common->luns[i]) */
-		/*		common->luns[i]->unit_attention_data = */
-		/*			SS_RESET_OCCURRED;  */
-		break;
-
-	case FSG_STATE_CONFIG_CHANGE:
-		do_set_interface(common, common->new_fsg);
-		if (common->new_fsg)
-			usb_composite_setup_continue(common->cdev);
-		break;
-
-	case FSG_STATE_EXIT:
-	case FSG_STATE_TERMINATED:
-		do_set_interface(common, NULL);		/* Free resources */
-		spin_lock_irq(&common->lock);
-		common->state = FSG_STATE_TERMINATED;	/* Stop the thread */
-		spin_unlock_irq(&common->lock);
-		break;
-
-	case FSG_STATE_INTERFACE_CHANGE:
-	case FSG_STATE_DISCONNECT:
-	case FSG_STATE_COMMAND_PHASE:
-	case FSG_STATE_DATA_PHASE:
-	case FSG_STATE_STATUS_PHASE:
-	case FSG_STATE_IDLE:
-		break;
-	}
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int fsg_main_thread(void *common_)
-{
-	struct fsg_common	*common = common_;
-
-	/*
-	 * Allow the thread to be killed by a signal, but set the signal mask
-	 * to block everything but INT, TERM, KILL, and USR1.
-	 */
-	allow_signal(SIGINT);
-	allow_signal(SIGTERM);
-	allow_signal(SIGKILL);
-	allow_signal(SIGUSR1);
-
-	/* Allow the thread to be frozen */
-	set_freezable();
-
-	/*
-	 * Arrange for userspace references to be interpreted as kernel
-	 * pointers.  That way we can pass a kernel pointer to a routine
-	 * that expects a __user pointer and it will work okay.
-	 */
-	set_fs(get_ds());
-
-	/* The main loop */
-	while (common->state != FSG_STATE_TERMINATED) {
-		if (exception_in_progress(common) || signal_pending(current)) {
-			handle_exception(common);
-			continue;
-		}
-
-		if (!common->running) {
-			sleep_thread(common, true);
-			continue;
-		}
-
-		if (get_next_command(common))
-			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_DATA_PHASE;
-		spin_unlock_irq(&common->lock);
-
-		if (do_scsi_command(common) || finish_reply(common))
-			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_STATUS_PHASE;
-		spin_unlock_irq(&common->lock);
-
-		if (send_status(common))
-			continue;
-
-		spin_lock_irq(&common->lock);
-		if (!exception_in_progress(common))
-			common->state = FSG_STATE_IDLE;
-		spin_unlock_irq(&common->lock);
-	}
-
-	spin_lock_irq(&common->lock);
-	common->thread_task = NULL;
-	spin_unlock_irq(&common->lock);
-
-	if (!common->ops || !common->ops->thread_exits
-	 || common->ops->thread_exits(common) < 0) {
-		struct fsg_lun **curlun_it = common->luns;
-		unsigned i = common->nluns;
-
-		down_write(&common->filesem);
-		for (; i--; ++curlun_it) {
-			struct fsg_lun *curlun = *curlun_it;
-			if (!curlun || !fsg_lun_is_open(curlun))
-				continue;
-
-			fsg_lun_close(curlun);
-			curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
-		}
-		up_write(&common->filesem);
-	}
-
-	/* Let fsg_unbind() know the thread has exited */
-	complete_and_exit(&common->thread_notifier, 0);
-}
-
-
-/*************************** DEVICE ATTRIBUTES ***************************/
-
-static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-
-	return fsg_show_ro(curlun, buf);
-}
-
-static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
-			  char *buf)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-
-	return fsg_show_nofua(curlun, buf);
-}
-
-static ssize_t file_show(struct device *dev, struct device_attribute *attr,
-			 char *buf)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-	struct rw_semaphore	*filesem = dev_get_drvdata(dev);
-
-	return fsg_show_file(curlun, filesem, buf);
-}
-
-static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
-			const char *buf, size_t count)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-	struct rw_semaphore	*filesem = dev_get_drvdata(dev);
-
-	return fsg_store_ro(curlun, filesem, buf, count);
-}
-
-static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
-			   const char *buf, size_t count)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-
-	return fsg_store_nofua(curlun, buf, count);
-}
-
-static ssize_t file_store(struct device *dev, struct device_attribute *attr,
-			  const char *buf, size_t count)
-{
-	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
-	struct rw_semaphore	*filesem = dev_get_drvdata(dev);
-
-	return fsg_store_file(curlun, filesem, buf, count);
-}
-
-static DEVICE_ATTR_RW(ro);
-static DEVICE_ATTR_RW(nofua);
-static DEVICE_ATTR_RW(file);
-
-static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro);
-static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file);
-
-
-/****************************** FSG COMMON ******************************/
-
-static void fsg_common_release(struct kref *ref);
-
-static void fsg_lun_release(struct device *dev)
-{
-	/* Nothing needs to be done */
-}
-
-void fsg_common_get(struct fsg_common *common)
-{
-	kref_get(&common->ref);
-}
-EXPORT_SYMBOL_GPL(fsg_common_get);
-
-void fsg_common_put(struct fsg_common *common)
-{
-	kref_put(&common->ref, fsg_common_release);
-}
-EXPORT_SYMBOL_GPL(fsg_common_put);
-
-/* check if fsg_num_buffers is within a valid range */
-static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
-{
-	if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
-		return 0;
-	pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
-	       fsg_num_buffers, 2, 4);
-	return -EINVAL;
-}
-
-static struct fsg_common *fsg_common_setup(struct fsg_common *common)
-{
-	if (!common) {
-		common = kzalloc(sizeof(*common), GFP_KERNEL);
-		if (!common)
-			return ERR_PTR(-ENOMEM);
-		common->free_storage_on_release = 1;
-	} else {
-		common->free_storage_on_release = 0;
-	}
-	init_rwsem(&common->filesem);
-	spin_lock_init(&common->lock);
-	kref_init(&common->ref);
-	init_completion(&common->thread_notifier);
-	init_waitqueue_head(&common->fsg_wait);
-	common->state = FSG_STATE_TERMINATED;
-
-	return common;
-}
-
-void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
-{
-	common->sysfs = sysfs;
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_sysfs);
-
-static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
-{
-	if (buffhds) {
-		struct fsg_buffhd *bh = buffhds;
-		while (n--) {
-			kfree(bh->buf);
-			++bh;
-		}
-		kfree(buffhds);
-	}
-}
-
-int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
-{
-	struct fsg_buffhd *bh, *buffhds;
-	int i, rc;
-
-	rc = fsg_num_buffers_validate(n);
-	if (rc != 0)
-		return rc;
-
-	buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
-	if (!buffhds)
-		return -ENOMEM;
-
-	/* Data buffers cyclic list */
-	bh = buffhds;
-	i = n;
-	goto buffhds_first_it;
-	do {
-		bh->next = bh + 1;
-		++bh;
-buffhds_first_it:
-		bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
-		if (unlikely(!bh->buf))
-			goto error_release;
-	} while (--i);
-	bh->next = buffhds;
-
-	_fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
-	common->fsg_num_buffers = n;
-	common->buffhds = buffhds;
-
-	return 0;
-
-error_release:
-	/*
-	 * "buf"s pointed to by heads after n - i are NULL
-	 * so releasing them won't hurt
-	 */
-	_fsg_common_free_buffers(buffhds, n);
-
-	return -ENOMEM;
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers);
-
-static inline void fsg_common_remove_sysfs(struct fsg_lun *lun)
-{
-	device_remove_file(&lun->dev, &dev_attr_nofua);
-	/*
-	 * device_remove_file() =>
-	 *
-	 * here the attr (e.g. dev_attr_ro) is only used to be passed to:
-	 *
-	 *	sysfs_remove_file() =>
-	 *
-	 *	here e.g. both dev_attr_ro_cdrom and dev_attr_ro are in
-	 *	the same namespace and
-	 *	from here only attr->name is passed to:
-	 *
-	 *		sysfs_hash_and_remove()
-	 *
-	 *		attr->name is the same for dev_attr_ro_cdrom and
-	 *		dev_attr_ro
-	 *		attr->name is the same for dev_attr_file and
-	 *		dev_attr_file_nonremovable
-	 *
-	 * so we don't differentiate between removing e.g. dev_attr_ro_cdrom
-	 * and dev_attr_ro
-	 */
-	device_remove_file(&lun->dev, &dev_attr_ro);
-	device_remove_file(&lun->dev, &dev_attr_file);
-}
-
-void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs)
-{
-	if (sysfs) {
-		fsg_common_remove_sysfs(lun);
-		device_unregister(&lun->dev);
-	}
-	fsg_lun_close(lun);
-	kfree(lun);
-}
-EXPORT_SYMBOL_GPL(fsg_common_remove_lun);
-
-static void _fsg_common_remove_luns(struct fsg_common *common, int n)
-{
-	int i;
-
-	for (i = 0; i < n; ++i)
-		if (common->luns[i]) {
-			fsg_common_remove_lun(common->luns[i], common->sysfs);
-			common->luns[i] = NULL;
-		}
-}
-EXPORT_SYMBOL_GPL(fsg_common_remove_luns);
-
-void fsg_common_remove_luns(struct fsg_common *common)
-{
-	_fsg_common_remove_luns(common, common->nluns);
-}
-
-void fsg_common_free_luns(struct fsg_common *common)
-{
-	fsg_common_remove_luns(common);
-	kfree(common->luns);
-	common->luns = NULL;
-}
-EXPORT_SYMBOL_GPL(fsg_common_free_luns);
-
-int fsg_common_set_nluns(struct fsg_common *common, int nluns)
-{
-	struct fsg_lun **curlun;
-
-	/* Find out how many LUNs there should be */
-	if (nluns < 1 || nluns > FSG_MAX_LUNS) {
-		pr_err("invalid number of LUNs: %u\n", nluns);
-		return -EINVAL;
-	}
-
-	curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
-	if (unlikely(!curlun))
-		return -ENOMEM;
-
-	if (common->luns)
-		fsg_common_free_luns(common);
-
-	common->luns = curlun;
-	common->nluns = nluns;
-
-	pr_info("Number of LUNs=%d\n", common->nluns);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_nluns);
-
-void fsg_common_set_ops(struct fsg_common *common,
-			const struct fsg_operations *ops)
-{
-	common->ops = ops;
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_ops);
-
-void fsg_common_free_buffers(struct fsg_common *common)
-{
-	_fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
-	common->buffhds = NULL;
-}
-EXPORT_SYMBOL_GPL(fsg_common_free_buffers);
-
-int fsg_common_set_cdev(struct fsg_common *common,
-			 struct usb_composite_dev *cdev, bool can_stall)
-{
-	struct usb_string *us;
-
-	common->gadget = cdev->gadget;
-	common->ep0 = cdev->gadget->ep0;
-	common->ep0req = cdev->req;
-	common->cdev = cdev;
-
-	us = usb_gstrings_attach(cdev, fsg_strings_array,
-				 ARRAY_SIZE(fsg_strings));
-	if (IS_ERR(us))
-		return PTR_ERR(us);
-
-	fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
-
-	/*
-	 * Some peripheral controllers are known not to be able to
-	 * halt bulk endpoints correctly.  If one of them is present,
-	 * disable stalls.
-	 */
-	common->can_stall = can_stall && !(gadget_is_at91(common->gadget));
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_cdev);
-
-static inline int fsg_common_add_sysfs(struct fsg_common *common,
-				       struct fsg_lun *lun)
-{
-	int rc;
-
-	rc = device_register(&lun->dev);
-	if (rc) {
-		put_device(&lun->dev);
-		return rc;
-	}
-
-	rc = device_create_file(&lun->dev,
-				lun->cdrom
-			      ? &dev_attr_ro_cdrom
-			      : &dev_attr_ro);
-	if (rc)
-		goto error;
-	rc = device_create_file(&lun->dev,
-				lun->removable
-			      ? &dev_attr_file
-			      : &dev_attr_file_nonremovable);
-	if (rc)
-		goto error;
-	rc = device_create_file(&lun->dev, &dev_attr_nofua);
-	if (rc)
-		goto error;
-
-	return 0;
-
-error:
-	/* removing nonexistent files is a no-op */
-	fsg_common_remove_sysfs(lun);
-	device_unregister(&lun->dev);
-	return rc;
-}
-
-int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
-			  unsigned int id, const char *name,
-			  const char **name_pfx)
-{
-	struct fsg_lun *lun;
-	char *pathbuf, *p;
-	int rc = -ENOMEM;
-
-	if (!common->nluns || !common->luns)
-		return -ENODEV;
-
-	if (common->luns[id])
-		return -EBUSY;
-
-	if (!cfg->filename && !cfg->removable) {
-		pr_err("no file given for LUN%d\n", id);
-		return -EINVAL;
-	}
-
-	lun = kzalloc(sizeof(*lun), GFP_KERNEL);
-	if (!lun)
-		return -ENOMEM;
-
-	lun->name_pfx = name_pfx;
-
-	lun->cdrom = !!cfg->cdrom;
-	lun->ro = cfg->cdrom || cfg->ro;
-	lun->initially_ro = lun->ro;
-	lun->removable = !!cfg->removable;
-
-	if (!common->sysfs) {
-		/* we DON'T own the name!*/
-		lun->name = name;
-	} else {
-		lun->dev.release = fsg_lun_release;
-		lun->dev.parent = &common->gadget->dev;
-		dev_set_drvdata(&lun->dev, &common->filesem);
-		dev_set_name(&lun->dev, "%s", name);
-		lun->name = dev_name(&lun->dev);
-
-		rc = fsg_common_add_sysfs(common, lun);
-		if (rc) {
-			pr_info("failed to register LUN%d: %d\n", id, rc);
-			goto error_sysfs;
-		}
-	}
-
-	common->luns[id] = lun;
-
-	if (cfg->filename) {
-		rc = fsg_lun_open(lun, cfg->filename);
-		if (rc)
-			goto error_lun;
-	}
-
-	pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
-	p = "(no medium)";
-	if (fsg_lun_is_open(lun)) {
-		p = "(error)";
-		if (pathbuf) {
-			p = d_path(&lun->filp->f_path, pathbuf, PATH_MAX);
-			if (IS_ERR(p))
-				p = "(error)";
-		}
-	}
-	pr_info("LUN: %s%s%sfile: %s\n",
-	      lun->removable ? "removable " : "",
-	      lun->ro ? "read only " : "",
-	      lun->cdrom ? "CD-ROM " : "",
-	      p);
-	kfree(pathbuf);
-
-	return 0;
-
-error_lun:
-	if (common->sysfs) {
-		fsg_common_remove_sysfs(lun);
-		device_unregister(&lun->dev);
-	}
-	fsg_lun_close(lun);
-	common->luns[id] = NULL;
-error_sysfs:
-	kfree(lun);
-	return rc;
-}
-EXPORT_SYMBOL_GPL(fsg_common_create_lun);
-
-int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
-{
-	char buf[8]; /* enough for 100000000 different numbers, decimal */
-	int i, rc;
-
-	for (i = 0; i < common->nluns; ++i) {
-		snprintf(buf, sizeof(buf), "lun%d", i);
-		rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
-		if (rc)
-			goto fail;
-	}
-
-	pr_info("Number of LUNs=%d\n", common->nluns);
-
-	return 0;
-
-fail:
-	_fsg_common_remove_luns(common, i);
-	return rc;
-}
-EXPORT_SYMBOL_GPL(fsg_common_create_luns);
-
-void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
-				   const char *pn)
-{
-	int i;
-
-	/* Prepare inquiryString */
-	i = get_default_bcdDevice();
-	snprintf(common->inquiry_string, sizeof(common->inquiry_string),
-		 "%-8s%-16s%04x", vn ?: "Linux",
-		 /* Assume product name dependent on the first LUN */
-		 pn ?: ((*common->luns)->cdrom
-		     ? "File-CD Gadget"
-		     : "File-Stor Gadget"),
-		 i);
-}
-EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
-
-int fsg_common_run_thread(struct fsg_common *common)
-{
-	common->state = FSG_STATE_IDLE;
-	/* Tell the thread to start working */
-	common->thread_task =
-		kthread_create(fsg_main_thread, common, "file-storage");
-	if (IS_ERR(common->thread_task)) {
-		common->state = FSG_STATE_TERMINATED;
-		return PTR_ERR(common->thread_task);
-	}
-
-	DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
-
-	wake_up_process(common->thread_task);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(fsg_common_run_thread);
-
-static void fsg_common_release(struct kref *ref)
-{
-	struct fsg_common *common = container_of(ref, struct fsg_common, ref);
-
-	/* If the thread isn't already dead, tell it to exit now */
-	if (common->state != FSG_STATE_TERMINATED) {
-		raise_exception(common, FSG_STATE_EXIT);
-		wait_for_completion(&common->thread_notifier);
-	}
-
-	if (likely(common->luns)) {
-		struct fsg_lun **lun_it = common->luns;
-		unsigned i = common->nluns;
-
-		/* In error recovery common->nluns may be zero. */
-		for (; i; --i, ++lun_it) {
-			struct fsg_lun *lun = *lun_it;
-			if (!lun)
-				continue;
-			if (common->sysfs)
-				fsg_common_remove_sysfs(lun);
-			fsg_lun_close(lun);
-			if (common->sysfs)
-				device_unregister(&lun->dev);
-			kfree(lun);
-		}
-
-		kfree(common->luns);
-	}
-
-	_fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
-	if (common->free_storage_on_release)
-		kfree(common);
-}
-
-
-/*-------------------------------------------------------------------------*/
-
-static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
-{
-	struct fsg_dev		*fsg = fsg_from_func(f);
-	struct usb_gadget	*gadget = c->cdev->gadget;
-	int			i;
-	struct usb_ep		*ep;
-	unsigned		max_burst;
-	int			ret;
-	struct fsg_opts		*opts;
-
-	opts = fsg_opts_from_func_inst(f->fi);
-	if (!opts->no_configfs) {
-		ret = fsg_common_set_cdev(fsg->common, c->cdev,
-					  fsg->common->can_stall);
-		if (ret)
-			return ret;
-		fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
-		ret = fsg_common_run_thread(fsg->common);
-		if (ret)
-			return ret;
-	}
-
-	fsg->gadget = gadget;
-
-	/* New interface */
-	i = usb_interface_id(c, f);
-	if (i < 0)
-		return i;
-	fsg_intf_desc.bInterfaceNumber = i;
-	fsg->interface_number = i;
-
-	/* Find all the endpoints we will use */
-	ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
-	if (!ep)
-		goto autoconf_fail;
-	ep->driver_data = fsg->common;	/* claim the endpoint */
-	fsg->bulk_in = ep;
-
-	ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
-	if (!ep)
-		goto autoconf_fail;
-	ep->driver_data = fsg->common;	/* claim the endpoint */
-	fsg->bulk_out = ep;
-
-	/* Assume endpoint addresses are the same for both speeds */
-	fsg_hs_bulk_in_desc.bEndpointAddress =
-		fsg_fs_bulk_in_desc.bEndpointAddress;
-	fsg_hs_bulk_out_desc.bEndpointAddress =
-		fsg_fs_bulk_out_desc.bEndpointAddress;
-
-	/* Calculate bMaxBurst, we know packet size is 1024 */
-	max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
-
-	fsg_ss_bulk_in_desc.bEndpointAddress =
-		fsg_fs_bulk_in_desc.bEndpointAddress;
-	fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
-
-	fsg_ss_bulk_out_desc.bEndpointAddress =
-		fsg_fs_bulk_out_desc.bEndpointAddress;
-	fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
-
-	ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
-			fsg_ss_function);
-	if (ret)
-		goto autoconf_fail;
-
-	return 0;
-
-autoconf_fail:
-	ERROR(fsg, "unable to autoconfigure all endpoints\n");
-	return -ENOTSUPP;
-}
-
-/****************************** ALLOCATE FUNCTION *************************/
-
-static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
-{
-	struct fsg_dev		*fsg = fsg_from_func(f);
-	struct fsg_common	*common = fsg->common;
-
-	DBG(fsg, "unbind\n");
-	if (fsg->common->fsg == fsg) {
-		fsg->common->new_fsg = NULL;
-		raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
-		/* FIXME: make interruptible or killable somehow? */
-		wait_event(common->fsg_wait, common->fsg != fsg);
-	}
-
-	usb_free_all_descriptors(&fsg->function);
-}
-
-static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item)
-{
-	return container_of(to_config_group(item), struct fsg_lun_opts, group);
-}
-
-static inline struct fsg_opts *to_fsg_opts(struct config_item *item)
-{
-	return container_of(to_config_group(item), struct fsg_opts,
-			    func_inst.group);
-}
-
-CONFIGFS_ATTR_STRUCT(fsg_lun_opts);
-CONFIGFS_ATTR_OPS(fsg_lun_opts);
-
-static void fsg_lun_attr_release(struct config_item *item)
-{
-	struct fsg_lun_opts *lun_opts;
-
-	lun_opts = to_fsg_lun_opts(item);
-	kfree(lun_opts);
-}
-
-static struct configfs_item_operations fsg_lun_item_ops = {
-	.release		= fsg_lun_attr_release,
-	.show_attribute		= fsg_lun_opts_attr_show,
-	.store_attribute	= fsg_lun_opts_attr_store,
-};
-
-static ssize_t fsg_lun_opts_file_show(struct fsg_lun_opts *opts, char *page)
-{
-	struct fsg_opts *fsg_opts;
-
-	fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
-
-	return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page);
-}
-
-static ssize_t fsg_lun_opts_file_store(struct fsg_lun_opts *opts,
-				       const char *page, size_t len)
-{
-	struct fsg_opts *fsg_opts;
-
-	fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
-
-	return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len);
-}
-
-static struct fsg_lun_opts_attribute fsg_lun_opts_file =
-	__CONFIGFS_ATTR(file, S_IRUGO | S_IWUSR, fsg_lun_opts_file_show,
-			fsg_lun_opts_file_store);
-
-static ssize_t fsg_lun_opts_ro_show(struct fsg_lun_opts *opts, char *page)
-{
-	return fsg_show_ro(opts->lun, page);
-}
-
-static ssize_t fsg_lun_opts_ro_store(struct fsg_lun_opts *opts,
-				       const char *page, size_t len)
-{
-	struct fsg_opts *fsg_opts;
-
-	fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
-
-	return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len);
-}
-
-static struct fsg_lun_opts_attribute fsg_lun_opts_ro =
-	__CONFIGFS_ATTR(ro, S_IRUGO | S_IWUSR, fsg_lun_opts_ro_show,
-			fsg_lun_opts_ro_store);
-
-static ssize_t fsg_lun_opts_removable_show(struct fsg_lun_opts *opts,
-					   char *page)
-{
-	return fsg_show_removable(opts->lun, page);
-}
-
-static ssize_t fsg_lun_opts_removable_store(struct fsg_lun_opts *opts,
-				       const char *page, size_t len)
-{
-	return fsg_store_removable(opts->lun, page, len);
-}
-
-static struct fsg_lun_opts_attribute fsg_lun_opts_removable =
-	__CONFIGFS_ATTR(removable, S_IRUGO | S_IWUSR,
-			fsg_lun_opts_removable_show,
-			fsg_lun_opts_removable_store);
-
-static ssize_t fsg_lun_opts_cdrom_show(struct fsg_lun_opts *opts, char *page)
-{
-	return fsg_show_cdrom(opts->lun, page);
-}
-
-static ssize_t fsg_lun_opts_cdrom_store(struct fsg_lun_opts *opts,
-				       const char *page, size_t len)
-{
-	struct fsg_opts *fsg_opts;
-
-	fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
-
-	return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page,
-			       len);
-}
-
-static struct fsg_lun_opts_attribute fsg_lun_opts_cdrom =
-	__CONFIGFS_ATTR(cdrom, S_IRUGO | S_IWUSR, fsg_lun_opts_cdrom_show,
-			fsg_lun_opts_cdrom_store);
-
-static ssize_t fsg_lun_opts_nofua_show(struct fsg_lun_opts *opts, char *page)
-{
-	return fsg_show_nofua(opts->lun, page);
-}
-
-static ssize_t fsg_lun_opts_nofua_store(struct fsg_lun_opts *opts,
-				       const char *page, size_t len)
-{
-	return fsg_store_nofua(opts->lun, page, len);
-}
-
-static struct fsg_lun_opts_attribute fsg_lun_opts_nofua =
-	__CONFIGFS_ATTR(nofua, S_IRUGO | S_IWUSR, fsg_lun_opts_nofua_show,
-			fsg_lun_opts_nofua_store);
-
-static struct configfs_attribute *fsg_lun_attrs[] = {
-	&fsg_lun_opts_file.attr,
-	&fsg_lun_opts_ro.attr,
-	&fsg_lun_opts_removable.attr,
-	&fsg_lun_opts_cdrom.attr,
-	&fsg_lun_opts_nofua.attr,
-	NULL,
-};
-
-static struct config_item_type fsg_lun_type = {
-	.ct_item_ops	= &fsg_lun_item_ops,
-	.ct_attrs	= fsg_lun_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-static struct config_group *fsg_lun_make(struct config_group *group,
-					 const char *name)
-{
-	struct fsg_lun_opts *opts;
-	struct fsg_opts *fsg_opts;
-	struct fsg_lun_config config;
-	char *num_str;
-	u8 num;
-	int ret;
-
-	num_str = strchr(name, '.');
-	if (!num_str) {
-		pr_err("Unable to locate . in LUN.NUMBER\n");
-		return ERR_PTR(-EINVAL);
-	}
-	num_str++;
-
-	ret = kstrtou8(num_str, 0, &num);
-	if (ret)
-		return ERR_PTR(ret);
-
-	fsg_opts = to_fsg_opts(&group->cg_item);
-	if (num >= FSG_MAX_LUNS)
-		return ERR_PTR(-ERANGE);
-
-	mutex_lock(&fsg_opts->lock);
-	if (fsg_opts->refcnt || fsg_opts->common->luns[num]) {
-		ret = -EBUSY;
-		goto out;
-	}
-
-	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
-	if (!opts) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	memset(&config, 0, sizeof(config));
-	config.removable = true;
-
-	ret = fsg_common_create_lun(fsg_opts->common, &config, num, name,
-				    (const char **)&group->cg_item.ci_name);
-	if (ret) {
-		kfree(opts);
-		goto out;
-	}
-	opts->lun = fsg_opts->common->luns[num];
-	opts->lun_id = num;
-	mutex_unlock(&fsg_opts->lock);
-
-	config_group_init_type_name(&opts->group, name, &fsg_lun_type);
-
-	return &opts->group;
-out:
-	mutex_unlock(&fsg_opts->lock);
-	return ERR_PTR(ret);
-}
-
-static void fsg_lun_drop(struct config_group *group, struct config_item *item)
-{
-	struct fsg_lun_opts *lun_opts;
-	struct fsg_opts *fsg_opts;
-
-	lun_opts = to_fsg_lun_opts(item);
-	fsg_opts = to_fsg_opts(&group->cg_item);
-
-	mutex_lock(&fsg_opts->lock);
-	if (fsg_opts->refcnt) {
-		struct config_item *gadget;
-
-		gadget = group->cg_item.ci_parent->ci_parent;
-		unregister_gadget_item(gadget);
-	}
-
-	fsg_common_remove_lun(lun_opts->lun, fsg_opts->common->sysfs);
-	fsg_opts->common->luns[lun_opts->lun_id] = NULL;
-	lun_opts->lun_id = 0;
-	mutex_unlock(&fsg_opts->lock);
-
-	config_item_put(item);
-}
-
-CONFIGFS_ATTR_STRUCT(fsg_opts);
-CONFIGFS_ATTR_OPS(fsg_opts);
-
-static void fsg_attr_release(struct config_item *item)
-{
-	struct fsg_opts *opts = to_fsg_opts(item);
-
-	usb_put_function_instance(&opts->func_inst);
-}
-
-static struct configfs_item_operations fsg_item_ops = {
-	.release		= fsg_attr_release,
-	.show_attribute		= fsg_opts_attr_show,
-	.store_attribute	= fsg_opts_attr_store,
-};
-
-static ssize_t fsg_opts_stall_show(struct fsg_opts *opts, char *page)
-{
-	int result;
-
-	mutex_lock(&opts->lock);
-	result = sprintf(page, "%d", opts->common->can_stall);
-	mutex_unlock(&opts->lock);
-
-	return result;
-}
-
-static ssize_t fsg_opts_stall_store(struct fsg_opts *opts, const char *page,
-				    size_t len)
-{
-	int ret;
-	bool stall;
-
-	mutex_lock(&opts->lock);
-
-	if (opts->refcnt) {
-		mutex_unlock(&opts->lock);
-		return -EBUSY;
-	}
-
-	ret = strtobool(page, &stall);
-	if (!ret) {
-		opts->common->can_stall = stall;
-		ret = len;
-	}
-
-	mutex_unlock(&opts->lock);
-
-	return ret;
-}
-
-static struct fsg_opts_attribute fsg_opts_stall =
-	__CONFIGFS_ATTR(stall, S_IRUGO | S_IWUSR, fsg_opts_stall_show,
-			fsg_opts_stall_store);
-
-#ifdef CONFIG_USB_GADGET_DEBUG_FILES
-static ssize_t fsg_opts_num_buffers_show(struct fsg_opts *opts, char *page)
-{
-	int result;
-
-	mutex_lock(&opts->lock);
-	result = sprintf(page, "%d", opts->common->fsg_num_buffers);
-	mutex_unlock(&opts->lock);
-
-	return result;
-}
-
-static ssize_t fsg_opts_num_buffers_store(struct fsg_opts *opts,
-					  const char *page, size_t len)
-{
-	int ret;
-	u8 num;
-
-	mutex_lock(&opts->lock);
-	if (opts->refcnt) {
-		ret = -EBUSY;
-		goto end;
-	}
-	ret = kstrtou8(page, 0, &num);
-	if (ret)
-		goto end;
-
-	ret = fsg_num_buffers_validate(num);
-	if (ret)
-		goto end;
-
-	fsg_common_set_num_buffers(opts->common, num);
-	ret = len;
-
-end:
-	mutex_unlock(&opts->lock);
-	return ret;
-}
-
-static struct fsg_opts_attribute fsg_opts_num_buffers =
-	__CONFIGFS_ATTR(num_buffers, S_IRUGO | S_IWUSR,
-			fsg_opts_num_buffers_show,
-			fsg_opts_num_buffers_store);
-
-#endif
-
-static struct configfs_attribute *fsg_attrs[] = {
-	&fsg_opts_stall.attr,
-#ifdef CONFIG_USB_GADGET_DEBUG_FILES
-	&fsg_opts_num_buffers.attr,
-#endif
-	NULL,
-};
-
-static struct configfs_group_operations fsg_group_ops = {
-	.make_group	= fsg_lun_make,
-	.drop_item	= fsg_lun_drop,
-};
-
-static struct config_item_type fsg_func_type = {
-	.ct_item_ops	= &fsg_item_ops,
-	.ct_group_ops	= &fsg_group_ops,
-	.ct_attrs	= fsg_attrs,
-	.ct_owner	= THIS_MODULE,
-};
-
-static void fsg_free_inst(struct usb_function_instance *fi)
-{
-	struct fsg_opts *opts;
-
-	opts = fsg_opts_from_func_inst(fi);
-	fsg_common_put(opts->common);
-	kfree(opts);
-}
-
-static struct usb_function_instance *fsg_alloc_inst(void)
-{
-	struct fsg_opts *opts;
-	struct fsg_lun_config config;
-	int rc;
-
-	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
-	if (!opts)
-		return ERR_PTR(-ENOMEM);
-	mutex_init(&opts->lock);
-	opts->func_inst.free_func_inst = fsg_free_inst;
-	opts->common = fsg_common_setup(opts->common);
-	if (IS_ERR(opts->common)) {
-		rc = PTR_ERR(opts->common);
-		goto release_opts;
-	}
-	rc = fsg_common_set_nluns(opts->common, FSG_MAX_LUNS);
-	if (rc)
-		goto release_opts;
-
-	rc = fsg_common_set_num_buffers(opts->common,
-					CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
-	if (rc)
-		goto release_luns;
-
-	pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
-
-	memset(&config, 0, sizeof(config));
-	config.removable = true;
-	rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0",
-			(const char **)&opts->func_inst.group.cg_item.ci_name);
-	opts->lun0.lun = opts->common->luns[0];
-	opts->lun0.lun_id = 0;
-	config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type);
-	opts->default_groups[0] = &opts->lun0.group;
-	opts->func_inst.group.default_groups = opts->default_groups;
-
-	config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type);
-
-	return &opts->func_inst;
-
-release_luns:
-	kfree(opts->common->luns);
-release_opts:
-	kfree(opts);
-	return ERR_PTR(rc);
-}
-
-static void fsg_free(struct usb_function *f)
-{
-	struct fsg_dev *fsg;
-	struct fsg_opts *opts;
-
-	fsg = container_of(f, struct fsg_dev, function);
-	opts = container_of(f->fi, struct fsg_opts, func_inst);
-
-	mutex_lock(&opts->lock);
-	opts->refcnt--;
-	mutex_unlock(&opts->lock);
-
-	kfree(fsg);
-}
-
-static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
-{
-	struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
-	struct fsg_common *common = opts->common;
-	struct fsg_dev *fsg;
-
-	fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
-	if (unlikely(!fsg))
-		return ERR_PTR(-ENOMEM);
-
-	mutex_lock(&opts->lock);
-	opts->refcnt++;
-	mutex_unlock(&opts->lock);
-	fsg->function.name	= FSG_DRIVER_DESC;
-	fsg->function.bind	= fsg_bind;
-	fsg->function.unbind	= fsg_unbind;
-	fsg->function.setup	= fsg_setup;
-	fsg->function.set_alt	= fsg_set_alt;
-	fsg->function.disable	= fsg_disable;
-	fsg->function.free_func	= fsg_free;
-
-	fsg->common               = common;
-
-	return &fsg->function;
-}
-
-DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Michal Nazarewicz");
-
-/************************* Module parameters *************************/
-
-
-void fsg_config_from_params(struct fsg_config *cfg,
-		       const struct fsg_module_parameters *params,
-		       unsigned int fsg_num_buffers)
-{
-	struct fsg_lun_config *lun;
-	unsigned i;
-
-	/* Configure LUNs */
-	cfg->nluns =
-		min(params->luns ?: (params->file_count ?: 1u),
-		    (unsigned)FSG_MAX_LUNS);
-	for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
-		lun->ro = !!params->ro[i];
-		lun->cdrom = !!params->cdrom[i];
-		lun->removable = !!params->removable[i];
-		lun->filename =
-			params->file_count > i && params->file[i][0]
-			? params->file[i]
-			: NULL;
-	}
-
-	/* Let MSF use defaults */
-	cfg->vendor_name = NULL;
-	cfg->product_name = NULL;
-
-	cfg->ops = NULL;
-	cfg->private_data = NULL;
-
-	/* Finalise */
-	cfg->can_stall = params->stall;
-	cfg->fsg_num_buffers = fsg_num_buffers;
-}
-EXPORT_SYMBOL_GPL(fsg_config_from_params);
-