USB: g_mass_storage: most data moved to fsg_common
authorMichal Nazarewicz <m.nazarewicz@samsung.com>
Mon, 9 Nov 2009 13:15:24 +0000 (14:15 +0100)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 11 Dec 2009 19:55:23 +0000 (11:55 -0800)
Most of the data from fsg_dev have been moved to fsg_common
structure.  The fsg_dev structure holds only endpoint dependent
data.  The fsg_common structure has a fsg pointer which points
to active fsg_dev structure -- endpoints are referenced via this
pointer.

This fixes the problem of several threads created when a single
instance of MSF is used in several USB configurations.

Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/gadget/f_mass_storage.c

index 5eaf22db7fccc9ce2de99d2fe825fdef6c8be952..a6cec37768a9edbf4dd51345e86cb17383976930 100644 (file)
@@ -312,14 +312,26 @@ static const char fsg_string_interface[] = "Mass Storage";
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
+struct fsg_dev;
+
 
 /* Data shared by all the FSG instances. */
 struct fsg_common {
        struct usb_gadget       *gadget;
 
 /* Data shared by all the FSG instances. */
 struct fsg_common {
        struct usb_gadget       *gadget;
+       struct fsg_dev          *fsg;
+       struct fsg_dev          *prev_fsg;
 
        /* filesem protects: backing files in use */
        struct rw_semaphore     filesem;
 
 
        /* 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;
+       const char              *ep0req_name;
+
        struct fsg_buffhd       *next_buffhd_to_fill;
        struct fsg_buffhd       *next_buffhd_to_drain;
        struct fsg_buffhd       buffhds[FSG_NUM_BUFFERS];
        struct fsg_buffhd       *next_buffhd_to_fill;
        struct fsg_buffhd       *next_buffhd_to_drain;
        struct fsg_buffhd       buffhds[FSG_NUM_BUFFERS];
@@ -332,10 +344,28 @@ struct fsg_common {
        struct fsg_lun          *luns;
        struct fsg_lun          *curlun;
 
        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;
+
+       u8                      config, new_config;
+       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            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;
 
 
-       const char              *thread_name;
+       int                     thread_wakeup_needed;
+       struct completion       thread_notifier;
+       struct task_struct      *thread_task;
 
        /* Vendor (8 chars), product (16 chars), release (4
         * hexadecimal digits) and NUL byte */
 
        /* Vendor (8 chars), product (16 chars), release (4
         * hexadecimal digits) and NUL byte */
@@ -367,52 +397,32 @@ struct fsg_config {
 
 struct fsg_dev {
        struct usb_function     function;
 
 struct fsg_dev {
        struct usb_function     function;
-       struct usb_composite_dev *cdev;
        struct usb_gadget       *gadget;        /* Copy of cdev->gadget */
        struct fsg_common       *common;
 
        u16                     interface_number;
 
        struct usb_gadget       *gadget;        /* Copy of cdev->gadget */
        struct fsg_common       *common;
 
        u16                     interface_number;
 
-       /* 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;
-       const char              *ep0req_name;
-
-       unsigned int            bulk_out_maxpacket;
-       enum fsg_state          state;          /* For exception handling */
-       unsigned int            exception_req_tag;
-
-       u8                      config, new_config;
-
-       unsigned int            running:1;
        unsigned int            bulk_in_enabled:1;
        unsigned int            bulk_out_enabled:1;
        unsigned int            bulk_in_enabled:1;
        unsigned int            bulk_out_enabled:1;
-       unsigned int            phase_error:1;
-       unsigned int            short_packet_received:1;
-       unsigned int            bad_lun_okay:1;
-       unsigned int            can_stall:1;
 
        unsigned long           atomic_bitflags;
 
        unsigned long           atomic_bitflags;
-#define REGISTERED             0
-#define IGNORE_BULK_OUT                1
+#define IGNORE_BULK_OUT                0
 
        struct usb_ep           *bulk_in;
        struct usb_ep           *bulk_out;
 
        struct usb_ep           *bulk_in;
        struct usb_ep           *bulk_out;
+};
 
 
-       int                     thread_wakeup_needed;
-       struct completion       thread_notifier;
-       struct task_struct      *thread_task;
 
 
-       enum data_direction     data_dir;
-       u32                     data_size;
-       u32                     data_size_from_cmnd;
-       u32                     tag;
-       u32                     residue;
-       u32                     usb_amount_left;
-};
+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);
+       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)
 
 
 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
@@ -423,21 +433,21 @@ static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
 
 typedef void (*fsg_routine_t)(struct fsg_dev *);
 
 
 typedef void (*fsg_routine_t)(struct fsg_dev *);
 
-static int exception_in_progress(struct fsg_dev *fsg)
+static int exception_in_progress(struct fsg_common *common)
 {
 {
-       return (fsg->state > FSG_STATE_IDLE);
+       return common->state > FSG_STATE_IDLE;
 }
 
 /* Make bulk-out requests be divisible by the maxpacket size */
 }
 
 /* Make bulk-out requests be divisible by the maxpacket size */
-static void set_bulk_out_req_length(struct fsg_dev *fsg,
+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;
                struct fsg_buffhd *bh, unsigned int length)
 {
        unsigned int    rem;
 
        bh->bulk_out_intended_length = length;
-       rem = length % fsg->bulk_out_maxpacket;
+       rem = length % common->bulk_out_maxpacket;
        if (rem > 0)
        if (rem > 0)
-               length += fsg->bulk_out_maxpacket - rem;
+               length += common->bulk_out_maxpacket - rem;
        bh->outreq->length = length;
 }
 
        bh->outreq->length = length;
 }
 
@@ -463,47 +473,46 @@ static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 /* These routines may be called in process context or in_irq */
 
 /* Caller must hold fsg->lock */
 /* These routines may be called in process context or in_irq */
 
 /* Caller must hold fsg->lock */
-static void wakeup_thread(struct fsg_dev *fsg)
+static void wakeup_thread(struct fsg_common *common)
 {
        /* Tell the main thread that something has happened */
 {
        /* Tell the main thread that something has happened */
-       fsg->thread_wakeup_needed = 1;
-       if (fsg->thread_task)
-               wake_up_process(fsg->thread_task);
+       common->thread_wakeup_needed = 1;
+       if (common->thread_task)
+               wake_up_process(common->thread_task);
 }
 
 
 }
 
 
-static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
+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. */
 {
        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(&fsg->lock, flags);
-       if (fsg->state <= new_state) {
-               fsg->exception_req_tag = fsg->ep0_req_tag;
-               fsg->state = new_state;
-               if (fsg->thread_task)
+       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,
                        send_sig_info(SIGUSR1, SEND_SIG_FORCED,
-                                       fsg->thread_task);
+                                     common->thread_task);
        }
        }
-       spin_unlock_irqrestore(&fsg->lock, flags);
+       spin_unlock_irqrestore(&common->lock, flags);
 }
 
 
 /*-------------------------------------------------------------------------*/
 
 }
 
 
 /*-------------------------------------------------------------------------*/
 
-static int ep0_queue(struct fsg_dev *fsg)
+static int ep0_queue(struct fsg_common *common)
 {
        int     rc;
 
 {
        int     rc;
 
-       rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
-       fsg->ep0->driver_data = fsg;
+       rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
+       common->ep0->driver_data = common;
        if (rc != 0 && rc != -ESHUTDOWN) {
        if (rc != 0 && rc != -ESHUTDOWN) {
-
                /* We can't do much more than wait for a reset */
                /* We can't do much more than wait for a reset */
-               WARNING(fsg, "error in submission: %s --> %d\n",
-                               fsg->ep0->name, rc);
+               WARNING(common, "error in submission: %s --> %d\n",
+                       common->ep0->name, rc);
        }
        return rc;
 }
        }
        return rc;
 }
@@ -515,32 +524,32 @@ static int ep0_queue(struct fsg_dev *fsg)
 
 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
 {
 
 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
 {
-       struct fsg_dev          *fsg = ep->driver_data;
+       struct fsg_common       *common = ep->driver_data;
        struct fsg_buffhd       *bh = req->context;
 
        if (req->status || req->actual != req->length)
        struct fsg_buffhd       *bh = req->context;
 
        if (req->status || req->actual != req->length)
-               DBG(fsg, "%s --> %d, %u/%u\n", __func__,
+               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();
                                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(&fsg->lock);
+       spin_lock(&common->lock);
        bh->inreq_busy = 0;
        bh->state = BUF_STATE_EMPTY;
        bh->inreq_busy = 0;
        bh->state = BUF_STATE_EMPTY;
-       wakeup_thread(fsg);
-       spin_unlock(&fsg->lock);
+       wakeup_thread(common);
+       spin_unlock(&common->lock);
 }
 
 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 {
 }
 
 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 {
-       struct fsg_dev          *fsg = ep->driver_data;
+       struct fsg_common       *common = ep->driver_data;
        struct fsg_buffhd       *bh = req->context;
 
        struct fsg_buffhd       *bh = req->context;
 
-       dump_msg(fsg, "bulk-out", req->buf, req->actual);
+       dump_msg(common, "bulk-out", req->buf, req->actual);
        if (req->status || req->actual != bh->bulk_out_intended_length)
        if (req->status || req->actual != bh->bulk_out_intended_length)
-               DBG(fsg, "%s --> %d, %u/%u\n", __func__,
+               DBG(common, "%s --> %d, %u/%u\n", __func__,
                                req->status, req->actual,
                                bh->bulk_out_intended_length);
        if (req->status == -ECONNRESET)         /* Request was cancelled */
                                req->status, req->actual,
                                bh->bulk_out_intended_length);
        if (req->status == -ECONNRESET)         /* Request was cancelled */
@@ -548,11 +557,11 @@ static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 
        /* Hold the lock while we update the request and buffer states */
        smp_wmb();
 
        /* Hold the lock while we update the request and buffer states */
        smp_wmb();
-       spin_lock(&fsg->lock);
+       spin_lock(&common->lock);
        bh->outreq_busy = 0;
        bh->state = BUF_STATE_FULL;
        bh->outreq_busy = 0;
        bh->state = BUF_STATE_FULL;
-       wakeup_thread(fsg);
-       spin_unlock(&fsg->lock);
+       wakeup_thread(common);
+       spin_unlock(&common->lock);
 }
 
 
 }
 
 
@@ -564,12 +573,12 @@ static int fsg_setup(struct usb_function *f,
                const struct usb_ctrlrequest *ctrl)
 {
        struct fsg_dev          *fsg = fsg_from_func(f);
                const struct usb_ctrlrequest *ctrl)
 {
        struct fsg_dev          *fsg = fsg_from_func(f);
-       struct usb_request      *req = fsg->ep0req;
+       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);
 
        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->config)
+       if (!fsg->common->config)
                return -EOPNOTSUPP;
 
        switch (ctrl->bRequest) {
                return -EOPNOTSUPP;
 
        switch (ctrl->bRequest) {
@@ -584,7 +593,7 @@ static int fsg_setup(struct usb_function *f,
                /* Raise an exception to stop the current operation
                 * and reinitialize our state. */
                DBG(fsg, "bulk reset request\n");
                /* Raise an exception to stop the current operation
                 * and reinitialize our state. */
                DBG(fsg, "bulk reset request\n");
-               raise_exception(fsg, FSG_STATE_RESET);
+               raise_exception(fsg->common, FSG_STATE_RESET);
                return DELAYED_STATUS;
 
        case USB_BULK_GET_MAX_LUN_REQUEST:
                return DELAYED_STATUS;
 
        case USB_BULK_GET_MAX_LUN_REQUEST:
@@ -622,10 +631,10 @@ static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
        if (ep == fsg->bulk_in)
                dump_msg(fsg, "bulk-in", req->buf, req->length);
 
        if (ep == fsg->bulk_in)
                dump_msg(fsg, "bulk-in", req->buf, req->length);
 
-       spin_lock_irq(&fsg->lock);
+       spin_lock_irq(&fsg->common->lock);
        *pbusy = 1;
        *state = BUF_STATE_BUSY;
        *pbusy = 1;
        *state = BUF_STATE_BUSY;
-       spin_unlock_irq(&fsg->lock);
+       spin_unlock_irq(&fsg->common->lock);
        rc = usb_ep_queue(ep, req, GFP_KERNEL);
        if (rc != 0) {
                *pbusy = 0;
        rc = usb_ep_queue(ep, req, GFP_KERNEL);
        if (rc != 0) {
                *pbusy = 0;
@@ -642,8 +651,18 @@ static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
        }
 }
 
        }
 }
 
+#define START_TRANSFER_OR(common, ep_name, req, pbusy, state)          \
+       if (fsg_is_set(common))                                         \
+               start_transfer((common)->fsg, (common)->fsg->ep_name,   \
+                              req, pbusy, state);                      \
+       else
+
+#define START_TRANSFER(common, ep_name, req, pbusy, state)             \
+       START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
+
+
 
 
-static int sleep_thread(struct fsg_dev *fsg)
+static int sleep_thread(struct fsg_common *common)
 {
        int     rc = 0;
 
 {
        int     rc = 0;
 
@@ -655,21 +674,21 @@ static int sleep_thread(struct fsg_dev *fsg)
                        rc = -EINTR;
                        break;
                }
                        rc = -EINTR;
                        break;
                }
-               if (fsg->thread_wakeup_needed)
+               if (common->thread_wakeup_needed)
                        break;
                schedule();
        }
        __set_current_state(TASK_RUNNING);
                        break;
                schedule();
        }
        __set_current_state(TASK_RUNNING);
-       fsg->thread_wakeup_needed = 0;
+       common->thread_wakeup_needed = 0;
        return rc;
 }
 
 
 /*-------------------------------------------------------------------------*/
 
        return rc;
 }
 
 
 /*-------------------------------------------------------------------------*/
 
-static int do_read(struct fsg_dev *fsg)
+static int do_read(struct fsg_common *common)
 {
 {
-       struct fsg_lun          *curlun = fsg->common->curlun;
+       struct fsg_lun          *curlun = common->curlun;
        u32                     lba;
        struct fsg_buffhd       *bh;
        int                     rc;
        u32                     lba;
        struct fsg_buffhd       *bh;
        int                     rc;
@@ -681,15 +700,15 @@ static int do_read(struct fsg_dev *fsg)
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
-       if (fsg->common->cmnd[0] == SC_READ_6)
-               lba = get_unaligned_be24(&fsg->common->cmnd[1]);
+       if (common->cmnd[0] == SC_READ_6)
+               lba = get_unaligned_be24(&common->cmnd[1]);
        else {
        else {
-               lba = get_unaligned_be32(&fsg->common->cmnd[2]);
+               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. */
 
                /* 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 ((fsg->common->cmnd[1] & ~0x18) != 0) {
+               if ((common->cmnd[1] & ~0x18) != 0) {
                        curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
                }
                        curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
                }
@@ -701,7 +720,7 @@ static int do_read(struct fsg_dev *fsg)
        file_offset = ((loff_t) lba) << 9;
 
        /* Carry out the file reads */
        file_offset = ((loff_t) lba) << 9;
 
        /* Carry out the file reads */
-       amount_left = fsg->data_size_from_cmnd;
+       amount_left = common->data_size_from_cmnd;
        if (unlikely(amount_left == 0))
                return -EIO;            /* No default reply */
 
        if (unlikely(amount_left == 0))
                return -EIO;            /* No default reply */
 
@@ -724,9 +743,9 @@ static int do_read(struct fsg_dev *fsg)
                                        partial_page);
 
                /* Wait for the next buffer to become available */
                                        partial_page);
 
                /* Wait for the next buffer to become available */
-               bh = fsg->common->next_buffhd_to_fill;
+               bh = common->next_buffhd_to_fill;
                while (bh->state != BUF_STATE_EMPTY) {
                while (bh->state != BUF_STATE_EMPTY) {
-                       rc = sleep_thread(fsg);
+                       rc = sleep_thread(common);
                        if (rc)
                                return rc;
                }
                        if (rc)
                                return rc;
                }
@@ -765,7 +784,7 @@ static int do_read(struct fsg_dev *fsg)
                }
                file_offset  += nread;
                amount_left  -= nread;
                }
                file_offset  += nread;
                amount_left  -= nread;
-               fsg->residue -= nread;
+               common->residue -= nread;
                bh->inreq->length = nread;
                bh->state = BUF_STATE_FULL;
 
                bh->inreq->length = nread;
                bh->state = BUF_STATE_FULL;
 
@@ -782,9 +801,12 @@ static int do_read(struct fsg_dev *fsg)
 
                /* Send this buffer and go read some more */
                bh->inreq->zero = 0;
 
                /* Send this buffer and go read some more */
                bh->inreq->zero = 0;
-               start_transfer(fsg, fsg->bulk_in, bh->inreq,
-                               &bh->inreq_busy, &bh->state);
-               fsg->common->next_buffhd_to_fill = bh->next;
+               START_TRANSFER_OR(common, bulk_in, bh->inreq,
+                              &bh->inreq_busy, &bh->state)
+                       /* 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 */
        }
 
        return -EIO;            /* No default reply */
@@ -793,9 +815,9 @@ static int do_read(struct fsg_dev *fsg)
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
-static int do_write(struct fsg_dev *fsg)
+static int do_write(struct fsg_common *common)
 {
 {
-       struct fsg_lun          *curlun = fsg->common->curlun;
+       struct fsg_lun          *curlun = common->curlun;
        u32                     lba;
        struct fsg_buffhd       *bh;
        int                     get_some_more;
        u32                     lba;
        struct fsg_buffhd       *bh;
        int                     get_some_more;
@@ -816,20 +838,20 @@ static int do_write(struct fsg_dev *fsg)
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
-       if (fsg->common->cmnd[0] == SC_WRITE_6)
-               lba = get_unaligned_be24(&fsg->common->cmnd[1]);
+       if (common->cmnd[0] == SC_WRITE_6)
+               lba = get_unaligned_be24(&common->cmnd[1]);
        else {
        else {
-               lba = get_unaligned_be32(&fsg->common->cmnd[2]);
+               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. */
 
                /* 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 ((fsg->common->cmnd[1] & ~0x18) != 0) {
+               if (common->cmnd[1] & ~0x18) {
                        curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
                }
                        curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
                }
-               if (fsg->common->cmnd[1] & 0x08) {      /* FUA */
+               if (common->cmnd[1] & 0x08) {   /* FUA */
                        spin_lock(&curlun->filp->f_lock);
                        curlun->filp->f_flags |= O_SYNC;
                        spin_unlock(&curlun->filp->f_lock);
                        spin_lock(&curlun->filp->f_lock);
                        curlun->filp->f_flags |= O_SYNC;
                        spin_unlock(&curlun->filp->f_lock);
@@ -843,12 +865,13 @@ static int do_write(struct fsg_dev *fsg)
        /* Carry out the file writes */
        get_some_more = 1;
        file_offset = usb_offset = ((loff_t) lba) << 9;
        /* Carry out the file writes */
        get_some_more = 1;
        file_offset = usb_offset = ((loff_t) lba) << 9;
-       amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd;
+       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 */
 
        while (amount_left_to_write > 0) {
 
                /* Queue a request for more data from the host */
-               bh = fsg->common->next_buffhd_to_fill;
+               bh = common->next_buffhd_to_fill;
                if (bh->state == BUF_STATE_EMPTY && get_some_more) {
 
                        /* Figure out how much we want to get:
                if (bh->state == BUF_STATE_EMPTY && get_some_more) {
 
                        /* Figure out how much we want to get:
@@ -887,7 +910,7 @@ static int do_write(struct fsg_dev *fsg)
 
                        /* Get the next buffer */
                        usb_offset += amount;
 
                        /* Get the next buffer */
                        usb_offset += amount;
-                       fsg->usb_amount_left -= amount;
+                       common->usb_amount_left -= amount;
                        amount_left_to_req -= amount;
                        if (amount_left_to_req == 0)
                                get_some_more = 0;
                        amount_left_to_req -= amount;
                        if (amount_left_to_req == 0)
                                get_some_more = 0;
@@ -897,19 +920,22 @@ static int do_write(struct fsg_dev *fsg)
                        bh->outreq->length = amount;
                        bh->bulk_out_intended_length = amount;
                        bh->outreq->short_not_ok = 1;
                        bh->outreq->length = amount;
                        bh->bulk_out_intended_length = amount;
                        bh->outreq->short_not_ok = 1;
-                       start_transfer(fsg, fsg->bulk_out, bh->outreq,
-                                       &bh->outreq_busy, &bh->state);
-                       fsg->common->next_buffhd_to_fill = bh->next;
+                       START_TRANSFER_OR(common, bulk_out, bh->outreq,
+                                         &bh->outreq_busy, &bh->state)
+                               /* Don't know 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 */
                        continue;
                }
 
                /* Write the received data to the backing file */
-               bh = fsg->common->next_buffhd_to_drain;
+               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();
                if (bh->state == BUF_STATE_EMPTY && !get_some_more)
                        break;                  /* We stopped early */
                if (bh->state == BUF_STATE_FULL) {
                        smp_rmb();
-                       fsg->common->next_buffhd_to_drain = bh->next;
+                       common->next_buffhd_to_drain = bh->next;
                        bh->state = BUF_STATE_EMPTY;
 
                        /* Did something go wrong with the transfer? */
                        bh->state = BUF_STATE_EMPTY;
 
                        /* Did something go wrong with the transfer? */
@@ -952,7 +978,7 @@ static int do_write(struct fsg_dev *fsg)
                        }
                        file_offset += nwritten;
                        amount_left_to_write -= nwritten;
                        }
                        file_offset += nwritten;
                        amount_left_to_write -= nwritten;
-                       fsg->residue -= nwritten;
+                       common->residue -= nwritten;
 
                        /* If an error occurred, report it and its position */
                        if (nwritten < amount) {
 
                        /* If an error occurred, report it and its position */
                        if (nwritten < amount) {
@@ -964,14 +990,14 @@ static int do_write(struct fsg_dev *fsg)
 
                        /* Did the host decide to stop early? */
                        if (bh->outreq->actual != bh->outreq->length) {
 
                        /* Did the host decide to stop early? */
                        if (bh->outreq->actual != bh->outreq->length) {
-                               fsg->short_packet_received = 1;
+                               common->short_packet_received = 1;
                                break;
                        }
                        continue;
                }
 
                /* Wait for something to happen */
                                break;
                        }
                        continue;
                }
 
                /* Wait for something to happen */
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
                if (rc)
                        return rc;
        }
@@ -982,9 +1008,9 @@ static int do_write(struct fsg_dev *fsg)
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
-static int do_synchronize_cache(struct fsg_dev *fsg)
+static int do_synchronize_cache(struct fsg_common *common)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
+       struct fsg_lun  *curlun = common->curlun;
        int             rc;
 
        /* We ignore the requested LBA and write out all file's
        int             rc;
 
        /* We ignore the requested LBA and write out all file's
@@ -1008,12 +1034,12 @@ static void invalidate_sub(struct fsg_lun *curlun)
        VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc);
 }
 
        VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc);
 }
 
-static int do_verify(struct fsg_dev *fsg)
+static int do_verify(struct fsg_common *common)
 {
 {
-       struct fsg_lun          *curlun = fsg->common->curlun;
+       struct fsg_lun          *curlun = common->curlun;
        u32                     lba;
        u32                     verification_length;
        u32                     lba;
        u32                     verification_length;
-       struct fsg_buffhd       *bh = fsg->common->next_buffhd_to_fill;
+       struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
        loff_t                  file_offset, file_offset_tmp;
        u32                     amount_left;
        unsigned int            amount;
        loff_t                  file_offset, file_offset_tmp;
        u32                     amount_left;
        unsigned int            amount;
@@ -1021,7 +1047,7 @@ static int do_verify(struct fsg_dev *fsg)
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
 
        /* Get the starting Logical Block Address and check that it's
         * not too big */
-       lba = get_unaligned_be32(&fsg->common->cmnd[2]);
+       lba = get_unaligned_be32(&common->cmnd[2]);
        if (lba >= curlun->num_sectors) {
                curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
                return -EINVAL;
        if (lba >= curlun->num_sectors) {
                curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
                return -EINVAL;
@@ -1029,12 +1055,12 @@ static int do_verify(struct fsg_dev *fsg)
 
        /* We allow DPO (Disable Page Out = don't save data in the
         * cache) but we don't implement it. */
 
        /* We allow DPO (Disable Page Out = don't save data in the
         * cache) but we don't implement it. */
-       if ((fsg->common->cmnd[1] & ~0x10) != 0) {
+       if (common->cmnd[1] & ~0x10) {
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
 
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
 
-       verification_length = get_unaligned_be16(&fsg->common->cmnd[7]);
+       verification_length = get_unaligned_be16(&common->cmnd[7]);
        if (unlikely(verification_length == 0))
                return -EIO;            /* No default reply */
 
        if (unlikely(verification_length == 0))
                return -EIO;            /* No default reply */
 
@@ -1106,13 +1132,13 @@ static int do_verify(struct fsg_dev *fsg)
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
-static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun *curlun = fsg->common->curlun;
+       struct fsg_lun *curlun = common->curlun;
        u8      *buf = (u8 *) bh->buf;
 
        if (!curlun) {          /* Unsupported LUNs are okay */
        u8      *buf = (u8 *) bh->buf;
 
        if (!curlun) {          /* Unsupported LUNs are okay */
-               fsg->bad_lun_okay = 1;
+               common->bad_lun_okay = 1;
                memset(buf, 0, 36);
                buf[0] = 0x7f;          /* Unsupported, no device-type */
                buf[4] = 31;            /* Additional length */
                memset(buf, 0, 36);
                buf[0] = 0x7f;          /* Unsupported, no device-type */
                buf[4] = 31;            /* Additional length */
@@ -1127,15 +1153,14 @@ static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
        buf[5] = 0;             /* No special options */
        buf[6] = 0;
        buf[7] = 0;
        buf[5] = 0;             /* No special options */
        buf[6] = 0;
        buf[7] = 0;
-       memcpy(buf + 8, fsg->common->inquiry_string,
-              sizeof fsg->common->inquiry_string);
+       memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
        return 36;
 }
 
 
        return 36;
 }
 
 
-static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
+       struct fsg_lun  *curlun = common->curlun;
        u8              *buf = (u8 *) bh->buf;
        u32             sd, sdinfo;
        int             valid;
        u8              *buf = (u8 *) bh->buf;
        u32             sd, sdinfo;
        int             valid;
@@ -1163,7 +1188,7 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 #endif
 
        if (!curlun) {          /* Unsupported LUNs are okay */
 #endif
 
        if (!curlun) {          /* Unsupported LUNs are okay */
-               fsg->bad_lun_okay = 1;
+               common->bad_lun_okay = 1;
                sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
                sdinfo = 0;
                valid = 0;
                sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
                sdinfo = 0;
                valid = 0;
@@ -1187,11 +1212,11 @@ static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 }
 
 
 }
 
 
-static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
-       u32             lba = get_unaligned_be32(&fsg->common->cmnd[2]);
-       int             pmi = fsg->common->cmnd[8];
+       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 */
        u8              *buf = (u8 *) bh->buf;
 
        /* Check the PMI and LBA fields */
@@ -1207,14 +1232,14 @@ static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 }
 
 
 }
 
 
-static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
-       int             msf = fsg->common->cmnd[1] & 0x02;
-       u32             lba = get_unaligned_be32(&fsg->common->cmnd[2]);
+       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;
 
        u8              *buf = (u8 *) bh->buf;
 
-       if ((fsg->common->cmnd[1] & ~0x02) != 0) {      /* Mask away MSF */
+       if (common->cmnd[1] & ~0x02) {          /* Mask away MSF */
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
@@ -1230,14 +1255,14 @@ static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 }
 
 
 }
 
 
-static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
-       int             msf = fsg->common->cmnd[1] & 0x02;
-       int             start_track = fsg->common->cmnd[6];
+       struct fsg_lun  *curlun = common->curlun;
+       int             msf = common->cmnd[1] & 0x02;
+       int             start_track = common->cmnd[6];
        u8              *buf = (u8 *) bh->buf;
 
        u8              *buf = (u8 *) bh->buf;
 
-       if ((fsg->common->cmnd[1] & ~0x02) != 0 ||      /* Mask away MSF */
+       if ((common->cmnd[1] & ~0x02) != 0 ||   /* Mask away MSF */
                        start_track > 1) {
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
                        start_track > 1) {
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
@@ -1258,10 +1283,10 @@ static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 }
 
 
 }
 
 
-static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
-       int             mscmnd = fsg->common->cmnd[0];
+       struct fsg_lun  *curlun = common->curlun;
+       int             mscmnd = common->cmnd[0];
        u8              *buf = (u8 *) bh->buf;
        u8              *buf0 = buf;
        int             pc, page_code;
        u8              *buf = (u8 *) bh->buf;
        u8              *buf0 = buf;
        int             pc, page_code;
@@ -1269,12 +1294,12 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
        int             valid_page = 0;
        int             len, limit;
 
        int             valid_page = 0;
        int             len, limit;
 
-       if ((fsg->common->cmnd[1] & ~0x08) != 0) {      /* Mask away DBD */
+       if ((common->cmnd[1] & ~0x08) != 0) {   /* Mask away DBD */
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
-       pc = fsg->common->cmnd[2] >> 6;
-       page_code = fsg->common->cmnd[2] & 0x3f;
+       pc = common->cmnd[2] >> 6;
+       page_code = common->cmnd[2] & 0x3f;
        if (pc == 3) {
                curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
                return -EINVAL;
        if (pc == 3) {
                curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
                return -EINVAL;
@@ -1339,32 +1364,32 @@ static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 }
 
 
 }
 
 
-static int do_start_stop(struct fsg_dev *fsg)
+static int do_start_stop(struct fsg_common *common)
 {
 {
-       if (!fsg->common->curlun) {
+       if (!common->curlun) {
                return -EINVAL;
                return -EINVAL;
-       } else if (!fsg->common->curlun->removable) {
-               fsg->common->curlun->sense_data = SS_INVALID_COMMAND;
+       } else if (!common->curlun->removable) {
+               common->curlun->sense_data = SS_INVALID_COMMAND;
                return -EINVAL;
        }
        return 0;
 }
 
 
                return -EINVAL;
        }
        return 0;
 }
 
 
-static int do_prevent_allow(struct fsg_dev *fsg)
+static int do_prevent_allow(struct fsg_common *common)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
+       struct fsg_lun  *curlun = common->curlun;
        int             prevent;
 
        int             prevent;
 
-       if (!fsg->common->curlun) {
+       if (!common->curlun) {
                return -EINVAL;
                return -EINVAL;
-       } else if (!fsg->common->curlun->removable) {
-               fsg->common->curlun->sense_data = SS_INVALID_COMMAND;
+       } else if (!common->curlun->removable) {
+               common->curlun->sense_data = SS_INVALID_COMMAND;
                return -EINVAL;
        }
 
                return -EINVAL;
        }
 
-       prevent = fsg->common->cmnd[4] & 0x01;
-       if ((fsg->common->cmnd[4] & ~0x01) != 0) {      /* Mask away Prevent */
+       prevent = common->cmnd[4] & 0x01;
+       if ((common->cmnd[4] & ~0x01) != 0) {   /* Mask away Prevent */
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                return -EINVAL;
        }
@@ -1376,10 +1401,10 @@ static int do_prevent_allow(struct fsg_dev *fsg)
 }
 
 
 }
 
 
-static int do_read_format_capacities(struct fsg_dev *fsg,
+static int do_read_format_capacities(struct fsg_common *common,
                        struct fsg_buffhd *bh)
 {
                        struct fsg_buffhd *bh)
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
+       struct fsg_lun  *curlun = common->curlun;
        u8              *buf = (u8 *) bh->buf;
 
        buf[0] = buf[1] = buf[2] = 0;
        u8              *buf = (u8 *) bh->buf;
 
        buf[0] = buf[1] = buf[2] = 0;
@@ -1394,12 +1419,13 @@ static int do_read_format_capacities(struct fsg_dev *fsg,
 }
 
 
 }
 
 
-static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
+static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
 {
 {
-       struct fsg_lun  *curlun = fsg->common->curlun;
+       struct fsg_lun  *curlun = common->curlun;
 
        /* We don't support MODE SELECT */
 
        /* We don't support MODE SELECT */
-       curlun->sense_data = SS_INVALID_COMMAND;
+       if (curlun)
+               curlun->sense_data = SS_INVALID_COMMAND;
        return -EINVAL;
 }
 
        return -EINVAL;
 }
 
@@ -1459,73 +1485,78 @@ static int pad_with_zeros(struct fsg_dev *fsg)
        int                     rc;
 
        bh->state = BUF_STATE_EMPTY;            /* For the first iteration */
        int                     rc;
 
        bh->state = BUF_STATE_EMPTY;            /* For the first iteration */
-       fsg->usb_amount_left = nkeep + fsg->residue;
-       while (fsg->usb_amount_left > 0) {
+       fsg->common->usb_amount_left = nkeep + fsg->common->residue;
+       while (fsg->common->usb_amount_left > 0) {
 
                /* Wait for the next buffer to be free */
                while (bh->state != BUF_STATE_EMPTY) {
 
                /* Wait for the next buffer to be free */
                while (bh->state != BUF_STATE_EMPTY) {
-                       rc = sleep_thread(fsg);
+                       rc = sleep_thread(fsg->common);
                        if (rc)
                                return rc;
                }
 
                        if (rc)
                                return rc;
                }
 
-               nsend = min(fsg->usb_amount_left, FSG_BUFLEN);
+               nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
                memset(bh->buf + nkeep, 0, nsend - nkeep);
                bh->inreq->length = nsend;
                bh->inreq->zero = 0;
                start_transfer(fsg, fsg->bulk_in, bh->inreq,
                                &bh->inreq_busy, &bh->state);
                bh = fsg->common->next_buffhd_to_fill = bh->next;
                memset(bh->buf + nkeep, 0, nsend - nkeep);
                bh->inreq->length = nsend;
                bh->inreq->zero = 0;
                start_transfer(fsg, fsg->bulk_in, bh->inreq,
                                &bh->inreq_busy, &bh->state);
                bh = fsg->common->next_buffhd_to_fill = bh->next;
-               fsg->usb_amount_left -= nsend;
+               fsg->common->usb_amount_left -= nsend;
                nkeep = 0;
        }
        return 0;
 }
 
                nkeep = 0;
        }
        return 0;
 }
 
-static int throw_away_data(struct fsg_dev *fsg)
+static int throw_away_data(struct fsg_common *common)
 {
        struct fsg_buffhd       *bh;
        u32                     amount;
        int                     rc;
 
 {
        struct fsg_buffhd       *bh;
        u32                     amount;
        int                     rc;
 
-       for (bh = fsg->common->next_buffhd_to_drain;
-            bh->state != BUF_STATE_EMPTY || fsg->usb_amount_left > 0;
-            bh = fsg->common->next_buffhd_to_drain) {
+       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;
 
                /* Throw away the data in a filled buffer */
                if (bh->state == BUF_STATE_FULL) {
                        smp_rmb();
                        bh->state = BUF_STATE_EMPTY;
-                       fsg->common->next_buffhd_to_drain = bh->next;
+                       common->next_buffhd_to_drain = bh->next;
 
                        /* A short packet or an error ends everything */
                        if (bh->outreq->actual != bh->outreq->length ||
                                        bh->outreq->status != 0) {
 
                        /* A short packet or an error ends everything */
                        if (bh->outreq->actual != bh->outreq->length ||
                                        bh->outreq->status != 0) {
-                               raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
+                               raise_exception(common,
+                                               FSG_STATE_ABORT_BULK_OUT);
                                return -EINTR;
                        }
                        continue;
                }
 
                /* Try to submit another request if we need one */
                                return -EINTR;
                        }
                        continue;
                }
 
                /* Try to submit another request if we need one */
-               bh = fsg->common->next_buffhd_to_fill;
-               if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
-                       amount = min(fsg->usb_amount_left, FSG_BUFLEN);
+               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);
 
                        /* amount is always divisible by 512, hence by
                         * the bulk-out maxpacket size */
                        bh->outreq->length = amount;
                        bh->bulk_out_intended_length = amount;
                        bh->outreq->short_not_ok = 1;
 
                        /* amount is always divisible by 512, hence by
                         * the bulk-out maxpacket size */
                        bh->outreq->length = amount;
                        bh->bulk_out_intended_length = amount;
                        bh->outreq->short_not_ok = 1;
-                       start_transfer(fsg, fsg->bulk_out, bh->outreq,
-                                       &bh->outreq_busy, &bh->state);
-                       fsg->common->next_buffhd_to_fill = bh->next;
-                       fsg->usb_amount_left -= amount;
+                       START_TRANSFER_OR(common, bulk_out, bh->outreq,
+                                         &bh->outreq_busy, &bh->state)
+                               /* Don't know 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 */
                        continue;
                }
 
                /* Otherwise wait for something to happen */
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
                if (rc)
                        return rc;
        }
@@ -1533,12 +1564,12 @@ static int throw_away_data(struct fsg_dev *fsg)
 }
 
 
 }
 
 
-static int finish_reply(struct fsg_dev *fsg)
+static int finish_reply(struct fsg_common *common)
 {
 {
-       struct fsg_buffhd       *bh = fsg->common->next_buffhd_to_fill;
+       struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
        int                     rc = 0;
 
        int                     rc = 0;
 
-       switch (fsg->data_dir) {
+       switch (common->data_dir) {
        case DATA_DIR_NONE:
                break;                  /* Nothing to send */
 
        case DATA_DIR_NONE:
                break;                  /* Nothing to send */
 
@@ -1547,47 +1578,60 @@ static int finish_reply(struct fsg_dev *fsg)
         * try to send or receive any data.  So stall both bulk pipes
         * if we can and wait for a reset. */
        case DATA_DIR_UNKNOWN:
         * 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 (fsg->can_stall) {
-                       fsg_set_halt(fsg, fsg->bulk_out);
-                       rc = halt_bulk_in_endpoint(fsg);
+               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:
                }
                break;
 
        /* All but the last buffer of data must have already been sent */
        case DATA_DIR_TO_HOST:
-               if (fsg->data_size == 0) {
+               if (common->data_size == 0) {
                        /* Nothing to send */
 
                /* If there's no residue, simply send the last buffer */
                        /* Nothing to send */
 
                /* If there's no residue, simply send the last buffer */
-               } else if (fsg->residue == 0) {
+               } else if (common->residue == 0) {
                        bh->inreq->zero = 0;
                        bh->inreq->zero = 0;
-                       start_transfer(fsg, fsg->bulk_in, bh->inreq,
-                                       &bh->inreq_busy, &bh->state);
-                       fsg->common->next_buffhd_to_fill = bh->next;
+                       START_TRANSFER_OR(common, bulk_in, bh->inreq,
+                                         &bh->inreq_busy, &bh->state)
+                               return -EIO;
+                       common->next_buffhd_to_fill = bh->next;
 
                /* For Bulk-only, if we're allowed to stall then send the
                 * short packet and halt the bulk-in endpoint.  If we can't
                 * stall, pad out the remaining data with 0's. */
 
                /* For Bulk-only, if we're allowed to stall then send the
                 * short packet and halt the bulk-in endpoint.  If we can't
                 * stall, pad out the remaining data with 0's. */
-               } else if (fsg->can_stall) {
+               } else if (common->can_stall) {
                        bh->inreq->zero = 1;
                        bh->inreq->zero = 1;
-                       start_transfer(fsg, fsg->bulk_in, bh->inreq,
-                                      &bh->inreq_busy, &bh->state);
-                       fsg->common->next_buffhd_to_fill = bh->next;
-                       rc = halt_bulk_in_endpoint(fsg);
+                       START_TRANSFER_OR(common, bulk_in, bh->inreq,
+                                         &bh->inreq_busy, &bh->state)
+                               /* Don't know what to do if
+                                * common->fsg is NULL */
+                               rc = -EIO;
+                       common->next_buffhd_to_fill = bh->next;
+                       if (common->fsg)
+                               rc = halt_bulk_in_endpoint(common->fsg);
+               } else if (fsg_is_set(common)) {
+                       rc = pad_with_zeros(common->fsg);
                } else {
                } else {
-                       rc = pad_with_zeros(fsg);
+                       /* Don't know what to do if common->fsg is NULL */
+                       rc = -EIO;
                }
                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:
                }
                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 (fsg->residue == 0) {
+               if (common->residue == 0) {
                        /* Nothing to receive */
 
                /* Did the host stop sending unexpectedly early? */
                        /* Nothing to receive */
 
                /* Did the host stop sending unexpectedly early? */
-               } else if (fsg->short_packet_received) {
-                       raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
+               } 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
                        rc = -EINTR;
 
                /* We haven't processed all the incoming data.  Even though
@@ -1597,16 +1641,18 @@ static int finish_reply(struct fsg_dev *fsg)
                 * STALL.  Not realizing the endpoint was halted, it wouldn't
                 * clear the halt -- leading to problems later on. */
 #if 0
                 * STALL.  Not realizing the endpoint was halted, it wouldn't
                 * clear the halt -- leading to problems later on. */
 #if 0
-               } else if (fsg->can_stall) {
-                       fsg_set_halt(fsg, fsg->bulk_out);
-                       raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
+               } 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 = -EINTR;
 #endif
 
                /* We can't stall.  Read in the excess data and throw it
                 * all away. */
                } else {
-                       rc = throw_away_data(fsg);
+                       rc = throw_away_data(common);
                }
                break;
        }
                }
                break;
        }
@@ -1614,9 +1660,9 @@ static int finish_reply(struct fsg_dev *fsg)
 }
 
 
 }
 
 
-static int send_status(struct fsg_dev *fsg)
+static int send_status(struct fsg_common *common)
 {
 {
-       struct fsg_lun          *curlun = fsg->common->curlun;
+       struct fsg_lun          *curlun = common->curlun;
        struct fsg_buffhd       *bh;
        struct bulk_cs_wrap     *csw;
        int                     rc;
        struct fsg_buffhd       *bh;
        struct bulk_cs_wrap     *csw;
        int                     rc;
@@ -1624,9 +1670,9 @@ static int send_status(struct fsg_dev *fsg)
        u32                     sd, sdinfo = 0;
 
        /* Wait for the next buffer to become available */
        u32                     sd, sdinfo = 0;
 
        /* Wait for the next buffer to become available */
-       bh = fsg->common->next_buffhd_to_fill;
+       bh = common->next_buffhd_to_fill;
        while (bh->state != BUF_STATE_EMPTY) {
        while (bh->state != BUF_STATE_EMPTY) {
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
                if (rc)
                        return rc;
        }
@@ -1634,19 +1680,19 @@ static int send_status(struct fsg_dev *fsg)
        if (curlun) {
                sd = curlun->sense_data;
                sdinfo = curlun->sense_data_info;
        if (curlun) {
                sd = curlun->sense_data;
                sdinfo = curlun->sense_data_info;
-       } else if (fsg->bad_lun_okay)
+       } else if (common->bad_lun_okay)
                sd = SS_NO_SENSE;
        else
                sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
 
                sd = SS_NO_SENSE;
        else
                sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
 
-       if (fsg->phase_error) {
-               DBG(fsg, "sending phase-error status\n");
+       if (common->phase_error) {
+               DBG(common, "sending phase-error status\n");
                status = USB_STATUS_PHASE_ERROR;
                sd = SS_INVALID_COMMAND;
        } else if (sd != SS_NO_SENSE) {
                status = USB_STATUS_PHASE_ERROR;
                sd = SS_INVALID_COMMAND;
        } else if (sd != SS_NO_SENSE) {
-               DBG(fsg, "sending command-failure status\n");
+               DBG(common, "sending command-failure status\n");
                status = USB_STATUS_FAIL;
                status = USB_STATUS_FAIL;
-               VDBG(fsg, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
+               VDBG(common, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
                                "  info x%x\n",
                                SK(sd), ASC(sd), ASCQ(sd), sdinfo);
        }
                                "  info x%x\n",
                                SK(sd), ASC(sd), ASCQ(sd), sdinfo);
        }
@@ -1655,16 +1701,18 @@ static int send_status(struct fsg_dev *fsg)
        csw = (void *)bh->buf;
 
        csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
        csw = (void *)bh->buf;
 
        csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
-       csw->Tag = fsg->tag;
-       csw->Residue = cpu_to_le32(fsg->residue);
+       csw->Tag = common->tag;
+       csw->Residue = cpu_to_le32(common->residue);
        csw->Status = status;
 
        bh->inreq->length = USB_BULK_CS_WRAP_LEN;
        bh->inreq->zero = 0;
        csw->Status = status;
 
        bh->inreq->length = USB_BULK_CS_WRAP_LEN;
        bh->inreq->zero = 0;
-       start_transfer(fsg, fsg->bulk_in, bh->inreq,
-                      &bh->inreq_busy, &bh->state);
+       START_TRANSFER_OR(common, bulk_in, bh->inreq,
+                         &bh->inreq_busy, &bh->state)
+               /* Don't know what to do if common->fsg is NULL */
+               return -EIO;
 
 
-       fsg->common->next_buffhd_to_fill = bh->next;
+       common->next_buffhd_to_fill = bh->next;
        return 0;
 }
 
        return 0;
 }
 
@@ -1673,52 +1721,47 @@ static int send_status(struct fsg_dev *fsg)
 
 /* Check whether the command is properly formed and whether its data size
  * and direction agree with the values we already have. */
 
 /* 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_dev *fsg, int cmnd_size,
+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;
                enum data_direction data_dir, unsigned int mask,
                int needs_medium, const char *name)
 {
        int                     i;
-       int                     lun = fsg->common->cmnd[1] >> 5;
+       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;
        static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
        char                    hdlen[20];
        struct fsg_lun          *curlun;
 
        hdlen[0] = 0;
-       if (fsg->data_dir != DATA_DIR_UNKNOWN)
-               sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
-                               fsg->data_size);
-       VDBG(fsg, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
+       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],
             name, cmnd_size, dirletter[(int) data_dir],
-            fsg->data_size_from_cmnd, fsg->common->cmnd_size, hdlen);
+            common->data_size_from_cmnd, common->cmnd_size, hdlen);
 
        /* We can't reply at all until we know the correct data direction
         * and size. */
 
        /* We can't reply at all until we know the correct data direction
         * and size. */
-       if (fsg->data_size_from_cmnd == 0)
+       if (common->data_size_from_cmnd == 0)
                data_dir = DATA_DIR_NONE;
                data_dir = DATA_DIR_NONE;
-       if (fsg->data_dir == DATA_DIR_UNKNOWN) {        /* CB or CBI */
-               fsg->data_dir = data_dir;
-               fsg->data_size = fsg->data_size_from_cmnd;
-
-       } else {                                        /* Bulk-only */
-               if (fsg->data_size < fsg->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. */
-                       fsg->data_size_from_cmnd = fsg->data_size;
-                       fsg->phase_error = 1;
-               }
+       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;
        }
        }
-       fsg->residue = fsg->usb_amount_left = fsg->data_size;
+       common->residue = common->data_size;
+       common->usb_amount_left = common->data_size;
 
        /* Conflicting data directions is a phase error */
 
        /* Conflicting data directions is a phase error */
-       if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
-               fsg->phase_error = 1;
+       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 */
                return -EINVAL;
        }
 
        /* Verify the length of the command itself */
-       if (cmnd_size != fsg->common->cmnd_size) {
+       if (cmnd_size != common->cmnd_size) {
 
                /* Special case workaround: There are plenty of buggy SCSI
                 * implementations. Many have issues with cbw->Length
 
                /* Special case workaround: There are plenty of buggy SCSI
                 * implementations. Many have issues with cbw->Length
@@ -1732,40 +1775,41 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size,
                 * REQUEST SENSE with cbw->Length == 10 where it should
                 * be 6 as well.
                 */
                 * REQUEST SENSE with cbw->Length == 10 where it should
                 * be 6 as well.
                 */
-               if (cmnd_size <= fsg->common->cmnd_size) {
-                       DBG(fsg, "%s is buggy! Expected length %d "
+               if (cmnd_size <= common->cmnd_size) {
+                       DBG(common, "%s is buggy! Expected length %d "
                            "but we got %d\n", name,
                            "but we got %d\n", name,
-                           cmnd_size, fsg->common->cmnd_size);
-                       cmnd_size = fsg->common->cmnd_size;
+                           cmnd_size, common->cmnd_size);
+                       cmnd_size = common->cmnd_size;
                } else {
                } else {
-                       fsg->phase_error = 1;
+                       common->phase_error = 1;
                        return -EINVAL;
                }
        }
 
        /* Check that the LUN values are consistent */
                        return -EINVAL;
                }
        }
 
        /* Check that the LUN values are consistent */
-       if (fsg->common->lun != lun)
-               DBG(fsg, "using LUN %d from CBW, not LUN %d from CDB\n",
-                   fsg->common->lun, lun);
+       if (common->lun != lun)
+               DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
+                   common->lun, lun);
 
        /* Check the LUN */
 
        /* Check the LUN */
-       if (fsg->common->lun >= 0 && fsg->common->lun < fsg->common->nluns) {
-               curlun = &fsg->common->luns[fsg->common->lun];
-               fsg->common->curlun = curlun;
-               if (fsg->common->cmnd[0] != SC_REQUEST_SENSE) {
+       if (common->lun >= 0 && common->lun < common->nluns) {
+               curlun = &common->luns[common->lun];
+               common->curlun = curlun;
+               if (common->cmnd[0] != SC_REQUEST_SENSE) {
                        curlun->sense_data = SS_NO_SENSE;
                        curlun->sense_data_info = 0;
                        curlun->info_valid = 0;
                }
        } else {
                        curlun->sense_data = SS_NO_SENSE;
                        curlun->sense_data_info = 0;
                        curlun->info_valid = 0;
                }
        } else {
-               fsg->common->curlun = curlun = NULL;
-               fsg->bad_lun_okay = 0;
+               common->curlun = NULL;
+               curlun = NULL;
+               common->bad_lun_okay = 0;
 
                /* INQUIRY and REQUEST SENSE commands are explicitly allowed
                 * to use unsupported LUNs; all others may not. */
 
                /* INQUIRY and REQUEST SENSE commands are explicitly allowed
                 * to use unsupported LUNs; all others may not. */
-               if (fsg->common->cmnd[0] != SC_INQUIRY &&
-                   fsg->common->cmnd[0] != SC_REQUEST_SENSE) {
-                       DBG(fsg, "unsupported LUN %d\n", fsg->common->lun);
+               if (common->cmnd[0] != SC_INQUIRY &&
+                   common->cmnd[0] != SC_REQUEST_SENSE) {
+                       DBG(common, "unsupported LUN %d\n", common->lun);
                        return -EINVAL;
                }
        }
                        return -EINVAL;
                }
        }
@@ -1773,17 +1817,17 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size,
        /* 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 &&
        /* 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 &&
-                       fsg->common->cmnd[0] != SC_INQUIRY &&
-                       fsg->common->cmnd[0] != SC_REQUEST_SENSE) {
+                       common->cmnd[0] != SC_INQUIRY &&
+                       common->cmnd[0] != SC_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 */
                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 */
-       fsg->common->cmnd[1] &= 0x1f;                   /* Mask away the LUN */
+       common->cmnd[1] &= 0x1f;                        /* Mask away the LUN */
        for (i = 1; i < cmnd_size; ++i) {
        for (i = 1; i < cmnd_size; ++i) {
-               if (fsg->common->cmnd[i] && !(mask & (1 << i))) {
+               if (common->cmnd[i] && !(mask & (1 << i))) {
                        if (curlun)
                                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
                        if (curlun)
                                curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
                        return -EINVAL;
@@ -1801,7 +1845,7 @@ static int check_command(struct fsg_dev *fsg, int cmnd_size,
 }
 
 
 }
 
 
-static int do_scsi_command(struct fsg_dev *fsg)
+static int do_scsi_command(struct fsg_common *common)
 {
        struct fsg_buffhd       *bh;
        int                     rc;
 {
        struct fsg_buffhd       *bh;
        int                     rc;
@@ -1809,182 +1853,181 @@ static int do_scsi_command(struct fsg_dev *fsg)
        int                     i;
        static char             unknown[16];
 
        int                     i;
        static char             unknown[16];
 
-       dump_cdb(fsg->common);
+       dump_cdb(common);
 
        /* Wait for the next buffer to become available for data or status */
 
        /* Wait for the next buffer to become available for data or status */
-       bh = fsg->common->next_buffhd_to_fill;
-       fsg->common->next_buffhd_to_drain = bh;
+       bh = common->next_buffhd_to_fill;
+       common->next_buffhd_to_drain = bh;
        while (bh->state != BUF_STATE_EMPTY) {
        while (bh->state != BUF_STATE_EMPTY) {
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
                if (rc)
                        return rc;
        }
-       fsg->phase_error = 0;
-       fsg->short_packet_received = 0;
+       common->phase_error = 0;
+       common->short_packet_received = 0;
 
 
-       /* We're using the backing file */
-       down_read(&fsg->common->filesem);
-       switch (fsg->common->cmnd[0]) {
+       down_read(&common->filesem);    /* We're using the backing file */
+       switch (common->cmnd[0]) {
 
        case SC_INQUIRY:
 
        case SC_INQUIRY:
-               fsg->data_size_from_cmnd = fsg->common->cmnd[4];
-               reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
+               common->data_size_from_cmnd = common->cmnd[4];
+               reply = check_command(common, 6, DATA_DIR_TO_HOST,
                                      (1<<4), 0,
                                      "INQUIRY");
                if (reply == 0)
                                      (1<<4), 0,
                                      "INQUIRY");
                if (reply == 0)
-                       reply = do_inquiry(fsg, bh);
+                       reply = do_inquiry(common, bh);
                break;
 
        case SC_MODE_SELECT_6:
                break;
 
        case SC_MODE_SELECT_6:
-               fsg->data_size_from_cmnd = fsg->common->cmnd[4];
-               reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
+               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)
                                      (1<<1) | (1<<4), 0,
                                      "MODE SELECT(6)");
                if (reply == 0)
-                       reply = do_mode_select(fsg, bh);
+                       reply = do_mode_select(common, bh);
                break;
 
        case SC_MODE_SELECT_10:
                break;
 
        case SC_MODE_SELECT_10:
-               fsg->data_size_from_cmnd =
-                       get_unaligned_be16(&fsg->common->cmnd[7]);
-               reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
+               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)
                                      (1<<1) | (3<<7), 0,
                                      "MODE SELECT(10)");
                if (reply == 0)
-                       reply = do_mode_select(fsg, bh);
+                       reply = do_mode_select(common, bh);
                break;
 
        case SC_MODE_SENSE_6:
                break;
 
        case SC_MODE_SENSE_6:
-               fsg->data_size_from_cmnd = fsg->common->cmnd[4];
-               reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
+               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)
                                      (1<<1) | (1<<2) | (1<<4), 0,
                                      "MODE SENSE(6)");
                if (reply == 0)
-                       reply = do_mode_sense(fsg, bh);
+                       reply = do_mode_sense(common, bh);
                break;
 
        case SC_MODE_SENSE_10:
                break;
 
        case SC_MODE_SENSE_10:
-               fsg->data_size_from_cmnd =
-                       get_unaligned_be16(&fsg->common->cmnd[7]);
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               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)
                                      (1<<1) | (1<<2) | (3<<7), 0,
                                      "MODE SENSE(10)");
                if (reply == 0)
-                       reply = do_mode_sense(fsg, bh);
+                       reply = do_mode_sense(common, bh);
                break;
 
        case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
                break;
 
        case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
-               fsg->data_size_from_cmnd = 0;
-               reply = check_command(fsg, 6, DATA_DIR_NONE,
+               common->data_size_from_cmnd = 0;
+               reply = check_command(common, 6, DATA_DIR_NONE,
                                      (1<<4), 0,
                                      "PREVENT-ALLOW MEDIUM REMOVAL");
                if (reply == 0)
                                      (1<<4), 0,
                                      "PREVENT-ALLOW MEDIUM REMOVAL");
                if (reply == 0)
-                       reply = do_prevent_allow(fsg);
+                       reply = do_prevent_allow(common);
                break;
 
        case SC_READ_6:
                break;
 
        case SC_READ_6:
-               i = fsg->common->cmnd[4];
-               fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
-               reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
+               i = common->cmnd[4];
+               common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
+               reply = check_command(common, 6, DATA_DIR_TO_HOST,
                                      (7<<1) | (1<<4), 1,
                                      "READ(6)");
                if (reply == 0)
                                      (7<<1) | (1<<4), 1,
                                      "READ(6)");
                if (reply == 0)
-                       reply = do_read(fsg);
+                       reply = do_read(common);
                break;
 
        case SC_READ_10:
                break;
 
        case SC_READ_10:
-               fsg->data_size_from_cmnd =
-                               get_unaligned_be16(&fsg->common->cmnd[7]) << 9;
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               common->data_size_from_cmnd =
+                               get_unaligned_be16(&common->cmnd[7]) << 9;
+               reply = check_command(common, 10, DATA_DIR_TO_HOST,
                                      (1<<1) | (0xf<<2) | (3<<7), 1,
                                      "READ(10)");
                if (reply == 0)
                                      (1<<1) | (0xf<<2) | (3<<7), 1,
                                      "READ(10)");
                if (reply == 0)
-                       reply = do_read(fsg);
+                       reply = do_read(common);
                break;
 
        case SC_READ_12:
                break;
 
        case SC_READ_12:
-               fsg->data_size_from_cmnd =
-                               get_unaligned_be32(&fsg->common->cmnd[6]) << 9;
-               reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
+               common->data_size_from_cmnd =
+                               get_unaligned_be32(&common->cmnd[6]) << 9;
+               reply = check_command(common, 12, DATA_DIR_TO_HOST,
                                      (1<<1) | (0xf<<2) | (0xf<<6), 1,
                                      "READ(12)");
                if (reply == 0)
                                      (1<<1) | (0xf<<2) | (0xf<<6), 1,
                                      "READ(12)");
                if (reply == 0)
-                       reply = do_read(fsg);
+                       reply = do_read(common);
                break;
 
        case SC_READ_CAPACITY:
                break;
 
        case SC_READ_CAPACITY:
-               fsg->data_size_from_cmnd = 8;
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               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)
                                      (0xf<<2) | (1<<8), 1,
                                      "READ CAPACITY");
                if (reply == 0)
-                       reply = do_read_capacity(fsg, bh);
+                       reply = do_read_capacity(common, bh);
                break;
 
        case SC_READ_HEADER:
                break;
 
        case SC_READ_HEADER:
-               if (!fsg->common->curlun || !fsg->common->curlun->cdrom)
+               if (!common->curlun || !common->curlun->cdrom)
                        goto unknown_cmnd;
                        goto unknown_cmnd;
-               fsg->data_size_from_cmnd =
-                       get_unaligned_be16(&fsg->common->cmnd[7]);
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               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)
                                      (3<<7) | (0x1f<<1), 1,
                                      "READ HEADER");
                if (reply == 0)
-                       reply = do_read_header(fsg, bh);
+                       reply = do_read_header(common, bh);
                break;
 
        case SC_READ_TOC:
                break;
 
        case SC_READ_TOC:
-               if (!fsg->common->curlun || !fsg->common->curlun->cdrom)
+               if (!common->curlun || !common->curlun->cdrom)
                        goto unknown_cmnd;
                        goto unknown_cmnd;
-               fsg->data_size_from_cmnd =
-                       get_unaligned_be16(&fsg->common->cmnd[7]);
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               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)
                                      (7<<6) | (1<<1), 1,
                                      "READ TOC");
                if (reply == 0)
-                       reply = do_read_toc(fsg, bh);
+                       reply = do_read_toc(common, bh);
                break;
 
        case SC_READ_FORMAT_CAPACITIES:
                break;
 
        case SC_READ_FORMAT_CAPACITIES:
-               fsg->data_size_from_cmnd =
-                       get_unaligned_be16(&fsg->common->cmnd[7]);
-               reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
+               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)
                                      (3<<7), 1,
                                      "READ FORMAT CAPACITIES");
                if (reply == 0)
-                       reply = do_read_format_capacities(fsg, bh);
+                       reply = do_read_format_capacities(common, bh);
                break;
 
        case SC_REQUEST_SENSE:
                break;
 
        case SC_REQUEST_SENSE:
-               fsg->data_size_from_cmnd = fsg->common->cmnd[4];
-               reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
+               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)
                                      (1<<4), 0,
                                      "REQUEST SENSE");
                if (reply == 0)
-                       reply = do_request_sense(fsg, bh);
+                       reply = do_request_sense(common, bh);
                break;
 
        case SC_START_STOP_UNIT:
                break;
 
        case SC_START_STOP_UNIT:
-               fsg->data_size_from_cmnd = 0;
-               reply = check_command(fsg, 6, DATA_DIR_NONE,
+               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)
                                      (1<<1) | (1<<4), 0,
                                      "START-STOP UNIT");
                if (reply == 0)
-                       reply = do_start_stop(fsg);
+                       reply = do_start_stop(common);
                break;
 
        case SC_SYNCHRONIZE_CACHE:
                break;
 
        case SC_SYNCHRONIZE_CACHE:
-               fsg->data_size_from_cmnd = 0;
-               reply = check_command(fsg, 10, DATA_DIR_NONE,
+               common->data_size_from_cmnd = 0;
+               reply = check_command(common, 10, DATA_DIR_NONE,
                                      (0xf<<2) | (3<<7), 1,
                                      "SYNCHRONIZE CACHE");
                if (reply == 0)
                                      (0xf<<2) | (3<<7), 1,
                                      "SYNCHRONIZE CACHE");
                if (reply == 0)
-                       reply = do_synchronize_cache(fsg);
+                       reply = do_synchronize_cache(common);
                break;
 
        case SC_TEST_UNIT_READY:
                break;
 
        case SC_TEST_UNIT_READY:
-               fsg->data_size_from_cmnd = 0;
-               reply = check_command(fsg, 6, DATA_DIR_NONE,
+               common->data_size_from_cmnd = 0;
+               reply = check_command(common, 6, DATA_DIR_NONE,
                                0, 1,
                                "TEST UNIT READY");
                break;
                                0, 1,
                                "TEST UNIT READY");
                break;
@@ -1992,42 +2035,42 @@ static int do_scsi_command(struct fsg_dev *fsg)
        /* Although optional, this command is used by MS-Windows.  We
         * support a minimal version: BytChk must be 0. */
        case SC_VERIFY:
        /* Although optional, this command is used by MS-Windows.  We
         * support a minimal version: BytChk must be 0. */
        case SC_VERIFY:
-               fsg->data_size_from_cmnd = 0;
-               reply = check_command(fsg, 10, DATA_DIR_NONE,
+               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)
                                      (1<<1) | (0xf<<2) | (3<<7), 1,
                                      "VERIFY");
                if (reply == 0)
-                       reply = do_verify(fsg);
+                       reply = do_verify(common);
                break;
 
        case SC_WRITE_6:
                break;
 
        case SC_WRITE_6:
-               i = fsg->common->cmnd[4];
-               fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
-               reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
+               i = common->cmnd[4];
+               common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
+               reply = check_command(common, 6, DATA_DIR_FROM_HOST,
                                      (7<<1) | (1<<4), 1,
                                      "WRITE(6)");
                if (reply == 0)
                                      (7<<1) | (1<<4), 1,
                                      "WRITE(6)");
                if (reply == 0)
-                       reply = do_write(fsg);
+                       reply = do_write(common);
                break;
 
        case SC_WRITE_10:
                break;
 
        case SC_WRITE_10:
-               fsg->data_size_from_cmnd =
-                               get_unaligned_be16(&fsg->common->cmnd[7]) << 9;
-               reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
+               common->data_size_from_cmnd =
+                               get_unaligned_be16(&common->cmnd[7]) << 9;
+               reply = check_command(common, 10, DATA_DIR_FROM_HOST,
                                      (1<<1) | (0xf<<2) | (3<<7), 1,
                                      "WRITE(10)");
                if (reply == 0)
                                      (1<<1) | (0xf<<2) | (3<<7), 1,
                                      "WRITE(10)");
                if (reply == 0)
-                       reply = do_write(fsg);
+                       reply = do_write(common);
                break;
 
        case SC_WRITE_12:
                break;
 
        case SC_WRITE_12:
-               fsg->data_size_from_cmnd =
-                               get_unaligned_be32(&fsg->common->cmnd[6]) << 9;
-               reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
+               common->data_size_from_cmnd =
+                               get_unaligned_be32(&common->cmnd[6]) << 9;
+               reply = check_command(common, 12, DATA_DIR_FROM_HOST,
                                      (1<<1) | (0xf<<2) | (0xf<<6), 1,
                                      "WRITE(12)");
                if (reply == 0)
                                      (1<<1) | (0xf<<2) | (0xf<<6), 1,
                                      "WRITE(12)");
                if (reply == 0)
-                       reply = do_write(fsg);
+                       reply = do_write(common);
                break;
 
        /* Some mandatory commands that we recognize but don't implement.
                break;
 
        /* Some mandatory commands that we recognize but don't implement.
@@ -2042,17 +2085,17 @@ static int do_scsi_command(struct fsg_dev *fsg)
 
        default:
 unknown_cmnd:
 
        default:
 unknown_cmnd:
-               fsg->data_size_from_cmnd = 0;
-               sprintf(unknown, "Unknown x%02x", fsg->common->cmnd[0]);
-               reply = check_command(fsg, fsg->common->cmnd_size,
+               common->data_size_from_cmnd = 0;
+               sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
+               reply = check_command(common, common->cmnd_size,
                                      DATA_DIR_UNKNOWN, 0xff, 0, unknown);
                if (reply == 0) {
                                      DATA_DIR_UNKNOWN, 0xff, 0, unknown);
                if (reply == 0) {
-                       fsg->common->curlun->sense_data = SS_INVALID_COMMAND;
+                       common->curlun->sense_data = SS_INVALID_COMMAND;
                        reply = -EINVAL;
                }
                break;
        }
                        reply = -EINVAL;
                }
                break;
        }
-       up_read(&fsg->common->filesem);
+       up_read(&common->filesem);
 
        if (reply == -EINTR || signal_pending(current))
                return -EINTR;
 
        if (reply == -EINTR || signal_pending(current))
                return -EINTR;
@@ -2060,11 +2103,11 @@ unknown_cmnd:
        /* Set up the single reply buffer for finish_reply() */
        if (reply == -EINVAL)
                reply = 0;              /* Error reply length */
        /* Set up the single reply buffer for finish_reply() */
        if (reply == -EINVAL)
                reply = 0;              /* Error reply length */
-       if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
-               reply = min((u32) reply, fsg->data_size_from_cmnd);
+       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;
                bh->inreq->length = reply;
                bh->state = BUF_STATE_FULL;
-               fsg->residue -= reply;
+               common->residue -= reply;
        }                               /* Otherwise it's already set */
 
        return 0;
        }                               /* Otherwise it's already set */
 
        return 0;
@@ -2075,8 +2118,9 @@ unknown_cmnd:
 
 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 {
 
 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 {
-       struct usb_request              *req = bh->outreq;
+       struct usb_request      *req = bh->outreq;
        struct fsg_bulk_cb_wrap *cbw = req->buf;
        struct fsg_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))
 
        /* Was this a real packet?  Should it be ignored? */
        if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
@@ -2113,7 +2157,7 @@ static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 
                /* We can do anything we want here, so let's stall the
                 * bulk pipes if we are allowed to. */
 
                /* We can do anything we want here, so let's stall the
                 * bulk pipes if we are allowed to. */
-               if (fsg->can_stall) {
+               if (common->can_stall) {
                        fsg_set_halt(fsg, fsg->bulk_out);
                        halt_bulk_in_endpoint(fsg);
                }
                        fsg_set_halt(fsg, fsg->bulk_out);
                        halt_bulk_in_endpoint(fsg);
                }
@@ -2121,39 +2165,41 @@ static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
        }
 
        /* Save the command for later */
        }
 
        /* Save the command for later */
-       fsg->common->cmnd_size = cbw->Length;
-       memcpy(fsg->common->cmnd, cbw->CDB, fsg->common->cmnd_size);
+       common->cmnd_size = cbw->Length;
+       memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
        if (cbw->Flags & USB_BULK_IN_FLAG)
        if (cbw->Flags & USB_BULK_IN_FLAG)
-               fsg->data_dir = DATA_DIR_TO_HOST;
+               common->data_dir = DATA_DIR_TO_HOST;
        else
        else
-               fsg->data_dir = DATA_DIR_FROM_HOST;
-       fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
-       if (fsg->data_size == 0)
-               fsg->data_dir = DATA_DIR_NONE;
-       fsg->common->lun = cbw->Lun;
-       fsg->tag = cbw->Tag;
+               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;
+       common->tag = cbw->Tag;
        return 0;
 }
 
 
        return 0;
 }
 
 
-static int get_next_command(struct fsg_dev *fsg)
+static int get_next_command(struct fsg_common *common)
 {
        struct fsg_buffhd       *bh;
        int                     rc = 0;
 
        /* Wait for the next buffer to become available */
 {
        struct fsg_buffhd       *bh;
        int                     rc = 0;
 
        /* Wait for the next buffer to become available */
-       bh = fsg->common->next_buffhd_to_fill;
+       bh = common->next_buffhd_to_fill;
        while (bh->state != BUF_STATE_EMPTY) {
        while (bh->state != BUF_STATE_EMPTY) {
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
 
        /* Queue a request to read a Bulk-only CBW */
                if (rc)
                        return rc;
        }
 
        /* Queue a request to read a Bulk-only CBW */
-       set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
+       set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
        bh->outreq->short_not_ok = 1;
        bh->outreq->short_not_ok = 1;
-       start_transfer(fsg, fsg->bulk_out, bh->outreq,
-                      &bh->outreq_busy, &bh->state);
+       START_TRANSFER_OR(common, bulk_out, bh->outreq,
+                         &bh->outreq_busy, &bh->state)
+               /* 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
 
        /* We will drain the buffer in software, which means we
         * can reuse it for the next filling.  No need to advance
@@ -2161,12 +2207,12 @@ static int get_next_command(struct fsg_dev *fsg)
 
        /* Wait for the CBW to arrive */
        while (bh->state != BUF_STATE_FULL) {
 
        /* Wait for the CBW to arrive */
        while (bh->state != BUF_STATE_FULL) {
-               rc = sleep_thread(fsg);
+               rc = sleep_thread(common);
                if (rc)
                        return rc;
        }
        smp_rmb();
                if (rc)
                        return rc;
        }
        smp_rmb();
-       rc = received_cbw(fsg, bh);
+       rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
        bh->state = BUF_STATE_EMPTY;
 
        return rc;
        bh->state = BUF_STATE_EMPTY;
 
        return rc;
@@ -2175,25 +2221,25 @@ static int get_next_command(struct fsg_dev *fsg)
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
-static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
+static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
                const struct usb_endpoint_descriptor *d)
 {
        int     rc;
 
                const struct usb_endpoint_descriptor *d)
 {
        int     rc;
 
-       ep->driver_data = fsg;
+       ep->driver_data = common;
        rc = usb_ep_enable(ep, d);
        if (rc)
        rc = usb_ep_enable(ep, d);
        if (rc)
-               ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
+               ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
        return rc;
 }
 
        return rc;
 }
 
-static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
+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;
                struct usb_request **preq)
 {
        *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
        if (*preq)
                return 0;
-       ERROR(fsg, "can't allocate request for %s\n", ep->name);
+       ERROR(common, "can't allocate request for %s\n", ep->name);
        return -ENOMEM;
 }
 
        return -ENOMEM;
 }
 
@@ -2202,83 +2248,96 @@ static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
  * Call with altsetting < 0 to disable the interface.  The only other
  * available altsetting is 0, which enables the interface.
  */
  * Call with altsetting < 0 to disable the interface.  The only other
  * available altsetting is 0, which enables the interface.
  */
-static int do_set_interface(struct fsg_dev *fsg, int altsetting)
+static int do_set_interface(struct fsg_common *common, int altsetting)
 {
        int     rc = 0;
        int     i;
        const struct usb_endpoint_descriptor    *d;
 
 {
        int     rc = 0;
        int     i;
        const struct usb_endpoint_descriptor    *d;
 
-       if (fsg->running)
-               DBG(fsg, "reset interface\n");
+       if (common->running)
+               DBG(common, "reset interface\n");
 
 reset:
        /* Deallocate the requests */
 
 reset:
        /* Deallocate the requests */
-       for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-               struct fsg_buffhd *bh = &fsg->common->buffhds[i];
+       if (common->prev_fsg) {
+               struct fsg_dev *fsg = common->prev_fsg;
+
+               for (i = 0; i < 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->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;
+                       }
                }
                }
-               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_enabled = 0;
+               }
+               if (fsg->bulk_out_enabled) {
+                       usb_ep_disable(fsg->bulk_out);
+                       fsg->bulk_out_enabled = 0;
                }
                }
-       }
 
 
-       /* Disable the endpoints */
-       if (fsg->bulk_in_enabled) {
-               usb_ep_disable(fsg->bulk_in);
-               fsg->bulk_in_enabled = 0;
-       }
-       if (fsg->bulk_out_enabled) {
-               usb_ep_disable(fsg->bulk_out);
-               fsg->bulk_out_enabled = 0;
+               common->prev_fsg = 0;
        }
 
        }
 
-       fsg->running = 0;
+       common->running = 0;
        if (altsetting < 0 || rc != 0)
                return rc;
 
        if (altsetting < 0 || rc != 0)
                return rc;
 
-       DBG(fsg, "set interface %d\n", altsetting);
-
-       /* Enable the endpoints */
-       d = fsg_ep_desc(fsg->gadget,
-                       &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
-       rc = enable_endpoint(fsg, fsg->bulk_in, d);
-       if (rc != 0)
-               goto reset;
-       fsg->bulk_in_enabled = 1;
-
-       d = fsg_ep_desc(fsg->gadget,
-                       &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
-       rc = enable_endpoint(fsg, fsg->bulk_out, d);
-       if (rc != 0)
-               goto reset;
-       fsg->bulk_out_enabled = 1;
-       fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
-       clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
-
-       /* Allocate the requests */
-       for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-               struct fsg_buffhd       *bh = &fsg->common->buffhds[i];
+       DBG(common, "set interface %d\n", altsetting);
 
 
-               rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq);
-               if (rc != 0)
+       if (fsg_is_set(common)) {
+               struct fsg_dev *fsg = common->fsg;
+               common->prev_fsg = common->fsg;
+
+               /* Enable the endpoints */
+               d = fsg_ep_desc(common->gadget,
+                               &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
+               rc = enable_endpoint(common, fsg->bulk_in, d);
+               if (rc)
                        goto reset;
                        goto reset;
-               rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq);
-               if (rc != 0)
+               fsg->bulk_in_enabled = 1;
+
+               d = fsg_ep_desc(common->gadget,
+                               &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
+               rc = enable_endpoint(common, fsg->bulk_out, d);
+               if (rc)
                        goto reset;
                        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;
-       }
+               fsg->bulk_out_enabled = 1;
+               common->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
+               clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
 
 
-       fsg->running = 1;
-       for (i = 0; i < fsg->common->nluns; ++i)
-               fsg->common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
-       return rc;
+               /* Allocate the requests */
+               for (i = 0; i < 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)
+                       common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
+               return rc;
+       } else {
+               return -EIO;
+       }
 }
 
 
 }
 
 
@@ -2290,23 +2349,23 @@ reset:
  * configurations might not work with our current power sources.
  * For now we just assume the gadget is always self-powered.
  */
  * configurations might not work with our current power sources.
  * For now we just assume the gadget is always self-powered.
  */
-static int do_set_config(struct fsg_dev *fsg, u8 new_config)
+static int do_set_config(struct fsg_common *common, u8 new_config)
 {
        int     rc = 0;
 
        /* Disable the single interface */
 {
        int     rc = 0;
 
        /* Disable the single interface */
-       if (fsg->config != 0) {
-               DBG(fsg, "reset config\n");
-               fsg->config = 0;
-               rc = do_set_interface(fsg, -1);
+       if (common->config != 0) {
+               DBG(common, "reset config\n");
+               common->config = 0;
+               rc = do_set_interface(common, -1);
        }
 
        /* Enable the interface */
        if (new_config != 0) {
        }
 
        /* Enable the interface */
        if (new_config != 0) {
-               fsg->config = new_config;
-               rc = do_set_interface(fsg, 0);
+               common->config = new_config;
+               rc = do_set_interface(common, 0);
                if (rc != 0)
                if (rc != 0)
-                       fsg->config = 0;        /* Reset on errors */
+                       common->config = 0;     /* Reset on errors */
        }
        return rc;
 }
        }
        return rc;
 }
@@ -2318,22 +2377,26 @@ static int do_set_config(struct fsg_dev *fsg, u8 new_config)
 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
        struct fsg_dev *fsg = fsg_from_func(f);
 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
        struct fsg_dev *fsg = fsg_from_func(f);
-       fsg->new_config = 1;
-       raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
+       fsg->common->prev_fsg = fsg->common->fsg;
+       fsg->common->fsg = fsg;
+       fsg->common->new_config = 1;
+       raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
        return 0;
 }
 
 static void fsg_disable(struct usb_function *f)
 {
        struct fsg_dev *fsg = fsg_from_func(f);
        return 0;
 }
 
 static void fsg_disable(struct usb_function *f)
 {
        struct fsg_dev *fsg = fsg_from_func(f);
-       fsg->new_config = 0;
-       raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
+       fsg->common->prev_fsg = fsg->common->fsg;
+       fsg->common->fsg = fsg;
+       fsg->common->new_config = 0;
+       raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
 }
 
 
 /*-------------------------------------------------------------------------*/
 
 }
 
 
 /*-------------------------------------------------------------------------*/
 
-static void handle_exception(struct fsg_dev *fsg)
+static void handle_exception(struct fsg_common *common)
 {
        siginfo_t               info;
        int                     sig;
 {
        siginfo_t               info;
        int                     sig;
@@ -2352,113 +2415,121 @@ static void handle_exception(struct fsg_dev *fsg)
                if (!sig)
                        break;
                if (sig != SIGUSR1) {
                if (!sig)
                        break;
                if (sig != SIGUSR1) {
-                       if (fsg->state < FSG_STATE_EXIT)
-                               DBG(fsg, "Main thread exiting on signal\n");
-                       raise_exception(fsg, FSG_STATE_EXIT);
+                       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 */
                }
        }
 
        /* Cancel all the pending transfers */
-       for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-               bh = &fsg->common->buffhds[i];
-               if (bh->inreq_busy)
-                       usb_ep_dequeue(fsg->bulk_in, bh->inreq);
-               if (bh->outreq_busy)
-                       usb_ep_dequeue(fsg->bulk_out, bh->outreq);
-       }
-
-       /* Wait until everything is idle */
-       for (;;) {
-               int num_active = 0;
+       if (fsg_is_set(common)) {
                for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
                for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-                       bh = &fsg->common->buffhds[i];
-                       num_active += bh->inreq_busy + bh->outreq_busy;
+                       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);
                }
                }
-               if (num_active == 0)
-                       break;
-               if (sleep_thread(fsg))
-                       return;
-       }
 
 
-       /* Clear out the controller's fifos */
-       if (fsg->bulk_in_enabled)
-               usb_ep_fifo_flush(fsg->bulk_in);
-       if (fsg->bulk_out_enabled)
-               usb_ep_fifo_flush(fsg->bulk_out);
+               /* Wait until everything is idle */
+               for (;;) {
+                       int num_active = 0;
+                       for (i = 0; i < 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))
+                               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. */
 
        /* Reset the I/O buffer states and pointers, the SCSI
         * state, and the exception.  Then invoke the handler. */
-       spin_lock_irq(&fsg->lock);
+       spin_lock_irq(&common->lock);
 
        for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
 
        for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
-               bh = &fsg->common->buffhds[i];
+               bh = &common->buffhds[i];
                bh->state = BUF_STATE_EMPTY;
        }
                bh->state = BUF_STATE_EMPTY;
        }
-       fsg->common->next_buffhd_to_fill = &fsg->common->buffhds[0];
-       fsg->common->next_buffhd_to_drain = &fsg->common->buffhds[0];
-       exception_req_tag = fsg->exception_req_tag;
-       new_config = fsg->new_config;
-       old_state = fsg->state;
+       common->next_buffhd_to_fill = &common->buffhds[0];
+       common->next_buffhd_to_drain = &common->buffhds[0];
+       exception_req_tag = common->exception_req_tag;
+       new_config = common->new_config;
+       old_state = common->state;
 
        if (old_state == FSG_STATE_ABORT_BULK_OUT)
 
        if (old_state == FSG_STATE_ABORT_BULK_OUT)
-               fsg->state = FSG_STATE_STATUS_PHASE;
+               common->state = FSG_STATE_STATUS_PHASE;
        else {
        else {
-               for (i = 0; i < fsg->common->nluns; ++i) {
-                       curlun = &fsg->common->luns[i];
+               for (i = 0; i < common->nluns; ++i) {
+                       curlun = &common->luns[i];
                        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;
                }
                        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;
                }
-               fsg->state = FSG_STATE_IDLE;
+               common->state = FSG_STATE_IDLE;
        }
        }
-       spin_unlock_irq(&fsg->lock);
+       spin_unlock_irq(&common->lock);
 
        /* Carry out any extra actions required for the exception */
        switch (old_state) {
        case FSG_STATE_ABORT_BULK_OUT:
 
        /* Carry out any extra actions required for the exception */
        switch (old_state) {
        case FSG_STATE_ABORT_BULK_OUT:
-               send_status(fsg);
-               spin_lock_irq(&fsg->lock);
-               if (fsg->state == FSG_STATE_STATUS_PHASE)
-                       fsg->state = FSG_STATE_IDLE;
-               spin_unlock_irq(&fsg->lock);
+               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.) */
                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 (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
-                       usb_ep_clear_halt(fsg->bulk_in);
+               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 (fsg->ep0_req_tag == exception_req_tag)
-                       ep0_queue(fsg); /* Complete the status stage */
+               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. */
 
                /* 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 < fsg->common->nluns; ++i) */
-               /*      fsg->common->luns[i].unit_attention_data = */
+               /* for (i = 0; i < common->nluns; ++i) */
+               /*      common->luns[i].unit_attention_data = */
                /*              SS_RESET_OCCURRED;  */
                break;
 
        case FSG_STATE_CONFIG_CHANGE:
                /*              SS_RESET_OCCURRED;  */
                break;
 
        case FSG_STATE_CONFIG_CHANGE:
-               rc = do_set_config(fsg, new_config);
-               if (fsg->ep0_req_tag != exception_req_tag)
+               rc = do_set_config(common, new_config);
+               if (common->ep0_req_tag != exception_req_tag)
                        break;
                        break;
-               if (rc != 0)                    /* STALL on errors */
-                       fsg_set_halt(fsg, fsg->ep0);
-               else                            /* Complete the status stage */
-                       ep0_queue(fsg);
+               if (rc != 0) {                  /* STALL on errors */
+                       DBG(common, "ep0 set halt\n");
+                       usb_ep_set_halt(common->ep0);
+               } else {                        /* Complete the status stage */
+                       ep0_queue(common);
+               }
                break;
 
        case FSG_STATE_EXIT:
        case FSG_STATE_TERMINATED:
                break;
 
        case FSG_STATE_EXIT:
        case FSG_STATE_TERMINATED:
-               do_set_config(fsg, 0);                  /* Free resources */
-               spin_lock_irq(&fsg->lock);
-               fsg->state = FSG_STATE_TERMINATED;      /* Stop the thread */
-               spin_unlock_irq(&fsg->lock);
+               do_set_config(common, 0);               /* 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:
                break;
 
        case FSG_STATE_INTERFACE_CHANGE:
@@ -2474,9 +2545,9 @@ static void handle_exception(struct fsg_dev *fsg)
 
 /*-------------------------------------------------------------------------*/
 
 
 /*-------------------------------------------------------------------------*/
 
-static int fsg_main_thread(void *fsg_)
+static int fsg_main_thread(void *common_)
 {
 {
-       struct fsg_dev          *fsg = fsg_;
+       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 the thread to be killed by a signal, but set the signal mask
         * to block everything but INT, TERM, KILL, and USR1. */
@@ -2494,45 +2565,45 @@ static int fsg_main_thread(void *fsg_)
        set_fs(get_ds());
 
        /* The main loop */
        set_fs(get_ds());
 
        /* The main loop */
-       while (fsg->state != FSG_STATE_TERMINATED) {
-               if (exception_in_progress(fsg) || signal_pending(current)) {
-                       handle_exception(fsg);
+       while (common->state != FSG_STATE_TERMINATED) {
+               if (exception_in_progress(common) || signal_pending(current)) {
+                       handle_exception(common);
                        continue;
                }
 
                        continue;
                }
 
-               if (!fsg->running) {
-                       sleep_thread(fsg);
+               if (!common->running) {
+                       sleep_thread(common);
                        continue;
                }
 
                        continue;
                }
 
-               if (get_next_command(fsg))
+               if (get_next_command(common))
                        continue;
 
                        continue;
 
-               spin_lock_irq(&fsg->lock);
-               if (!exception_in_progress(fsg))
-                       fsg->state = FSG_STATE_DATA_PHASE;
-               spin_unlock_irq(&fsg->lock);
+               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(fsg) || finish_reply(fsg))
+               if (do_scsi_command(common) || finish_reply(common))
                        continue;
 
                        continue;
 
-               spin_lock_irq(&fsg->lock);
-               if (!exception_in_progress(fsg))
-                       fsg->state = FSG_STATE_STATUS_PHASE;
-               spin_unlock_irq(&fsg->lock);
+               spin_lock_irq(&common->lock);
+               if (!exception_in_progress(common))
+                       common->state = FSG_STATE_STATUS_PHASE;
+               spin_unlock_irq(&common->lock);
 
 
-               if (send_status(fsg))
+               if (send_status(common))
                        continue;
 
                        continue;
 
-               spin_lock_irq(&fsg->lock);
-               if (!exception_in_progress(fsg))
-                       fsg->state = FSG_STATE_IDLE;
-               spin_unlock_irq(&fsg->lock);
+               spin_lock_irq(&common->lock);
+               if (!exception_in_progress(common))
+                       common->state = FSG_STATE_IDLE;
+               spin_unlock_irq(&common->lock);
        }
 
        }
 
-       spin_lock_irq(&fsg->lock);
-       fsg->thread_task = NULL;
-       spin_unlock_irq(&fsg->lock);
+       spin_lock_irq(&common->lock);
+       common->thread_task = NULL;
+       spin_unlock_irq(&common->lock);
 
        /* XXX */
        /* If we are exiting because of a signal, unregister the
 
        /* XXX */
        /* If we are exiting because of a signal, unregister the
@@ -2541,7 +2612,7 @@ static int fsg_main_thread(void *fsg_)
        /*      usb_gadget_unregister_driver(&fsg_driver); */
 
        /* Let the unbind and cleanup routines know the thread has exited */
        /*      usb_gadget_unregister_driver(&fsg_driver); */
 
        /* Let the unbind and cleanup routines know the thread has exited */
-       complete_and_exit(&fsg->thread_notifier, 0);
+       complete_and_exit(&common->thread_notifier, 0);
 }
 
 
 }
 
 
@@ -2600,7 +2671,21 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
                memset(common, 0, sizeof common);
                common->free_storage_on_release = 0;
        }
                memset(common, 0, sizeof common);
                common->free_storage_on_release = 0;
        }
+
        common->gadget = gadget;
        common->gadget = gadget;
+       common->ep0 = gadget->ep0;
+       common->ep0req = cdev->req;
+
+       /* Maybe allocate device-global string IDs, and patch descriptors */
+       if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
+               rc = usb_string_id(cdev);
+               if (rc < 0) {
+                       kfree(common);
+                       return ERR_PTR(rc);
+               }
+               fsg_strings[FSG_STRING_INTERFACE].id = rc;
+               fsg_intf_desc.iInterface = rc;
+       }
 
        /* Create the LUNs, open their backing files, and register the
         * LUN devices in sysfs. */
 
        /* Create the LUNs, open their backing files, and register the
         * LUN devices in sysfs. */
@@ -2697,11 +2782,23 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
         * disable stalls.
         */
        common->can_stall = cfg->can_stall &&
         * disable stalls.
         */
        common->can_stall = cfg->can_stall &&
-               !(gadget_is_sh(fsg->gadget) || gadget_is_at91(fsg->gadget));
+               !(gadget_is_sh(common->gadget) ||
+                 gadget_is_at91(common->gadget));
 
 
 
 
-       common->thread_name = OR(cfg->thread_name, "file-storage");
+       spin_lock_init(&common->lock);
        kref_init(&common->ref);
        kref_init(&common->ref);
+
+
+       /* Tell the thread to start working */
+       common->thread_task =
+               kthread_create(fsg_main_thread, common,
+                              OR(cfg->thread_name, "file-storage"));
+       if (IS_ERR(common->thread_task)) {
+               rc = PTR_ERR(common->thread_task);
+               goto error_release;
+       }
+       init_completion(&common->thread_notifier);
 #undef OR
 
 
 #undef OR
 
 
@@ -2731,15 +2828,21 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
        }
        kfree(pathbuf);
 
        }
        kfree(pathbuf);
 
+       DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
+
+       wake_up_process(common->thread_task);
+
        return common;
 
 
 error_luns:
        common->nluns = i + 1;
 error_release:
        return common;
 
 
 error_luns:
        common->nluns = i + 1;
 error_release:
+       common->state = FSG_STATE_TERMINATED;   /* The thread is dead */
        /* Call fsg_common_release() directly, ref might be not
         * initialised */
        fsg_common_release(&common->ref);
        /* Call fsg_common_release() directly, ref might be not
         * initialised */
        fsg_common_release(&common->ref);
+       complete(&common->thread_notifier);
        return ERR_PTR(rc);
 }
 
        return ERR_PTR(rc);
 }
 
@@ -2751,6 +2854,15 @@ static void fsg_common_release(struct kref *ref)
        unsigned i = common->nluns;
        struct fsg_lun *lun = common->luns;
 
        unsigned i = common->nluns;
        struct fsg_lun *lun = common->luns;
 
+       /* 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);
+
+               /* The cleanup routine waits for this completion also */
+               complete(&common->thread_notifier);
+       }
+
        /* Beware tempting for -> do-while optimization: when in error
         * recovery nluns may be zero. */
 
        /* Beware tempting for -> do-while optimization: when in error
         * recovery nluns may be zero. */
 
@@ -2775,17 +2887,6 @@ static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
        struct fsg_dev          *fsg = fsg_from_func(f);
 
        DBG(fsg, "unbind\n");
        struct fsg_dev          *fsg = fsg_from_func(f);
 
        DBG(fsg, "unbind\n");
-       clear_bit(REGISTERED, &fsg->atomic_bitflags);
-
-       /* If the thread isn't already dead, tell it to exit now */
-       if (fsg->state != FSG_STATE_TERMINATED) {
-               raise_exception(fsg, FSG_STATE_EXIT);
-               wait_for_completion(&fsg->thread_notifier);
-
-               /* The cleanup routine waits for this completion also */
-               complete(&fsg->thread_notifier);
-       }
-
        fsg_common_put(fsg->common);
        kfree(fsg);
 }
        fsg_common_put(fsg->common);
        kfree(fsg);
 }
@@ -2800,8 +2901,6 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
        struct usb_ep           *ep;
 
        fsg->gadget = gadget;
        struct usb_ep           *ep;
 
        fsg->gadget = gadget;
-       fsg->ep0 = gadget->ep0;
-       fsg->ep0req = c->cdev->req;
 
        /* New interface */
        i = usb_interface_id(c, f);
 
        /* New interface */
        i = usb_interface_id(c, f);
@@ -2814,13 +2913,13 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
        ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
        if (!ep)
                goto autoconf_fail;
        ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
        if (!ep)
                goto autoconf_fail;
-       ep->driver_data = fsg;          /* claim the endpoint */
+       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;
        fsg->bulk_in = ep;
 
        ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
        if (!ep)
                goto autoconf_fail;
-       ep->driver_data = fsg;          /* claim the endpoint */
+       ep->driver_data = fsg->common;  /* claim the endpoint */
        fsg->bulk_out = ep;
 
        if (gadget_is_dualspeed(gadget)) {
        fsg->bulk_out = ep;
 
        if (gadget_is_dualspeed(gadget)) {
@@ -2832,40 +2931,12 @@ static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
                f->hs_descriptors = fsg_hs_function;
        }
 
                f->hs_descriptors = fsg_hs_function;
        }
 
-
-       /* maybe allocate device-global string IDs, and patch descriptors */
-       if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
-               i = usb_string_id(c->cdev);
-               if (i < 0)
-                       return i;
-               fsg_strings[FSG_STRING_INTERFACE].id = i;
-               fsg_intf_desc.iInterface = i;
-       }
-
-
-       fsg->thread_task = kthread_create(fsg_main_thread, fsg,
-                                         fsg->common->thread_name);
-       if (IS_ERR(fsg->thread_task)) {
-               rc = PTR_ERR(fsg->thread_task);
-               goto out;
-       }
-
-       DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
-
-       set_bit(REGISTERED, &fsg->atomic_bitflags);
-
-       /* Tell the thread to start working */
-       wake_up_process(fsg->thread_task);
        return 0;
 
 autoconf_fail:
        ERROR(fsg, "unable to autoconfigure all endpoints\n");
        rc = -ENOTSUPP;
        return 0;
 
 autoconf_fail:
        ERROR(fsg, "unable to autoconfigure all endpoints\n");
        rc = -ENOTSUPP;
-
-out:
-       fsg->state = FSG_STATE_TERMINATED;      /* The thread is dead */
        fsg_unbind(c, f);
        fsg_unbind(c, f);
-       complete(&fsg->thread_notifier);
        return rc;
 }
 
        return rc;
 }
 
@@ -2888,10 +2959,6 @@ static int fsg_add(struct usb_composite_dev *cdev,
        if (unlikely(!fsg))
                return -ENOMEM;
 
        if (unlikely(!fsg))
                return -ENOMEM;
 
-       spin_lock_init(&fsg->lock);
-       init_completion(&fsg->thread_notifier);
-
-       fsg->cdev                 = cdev;
        fsg->function.name        = FSG_DRIVER_DESC;
        fsg->function.strings     = fsg_strings_array;
        fsg->function.descriptors = fsg_fs_function;
        fsg->function.name        = FSG_DRIVER_DESC;
        fsg->function.strings     = fsg_strings_array;
        fsg->function.descriptors = fsg_fs_function;
@@ -2907,7 +2974,6 @@ static int fsg_add(struct usb_composite_dev *cdev,
         * from this function.  So instead of incrementing counter now
         * and decrement in error recovery we increment it only when
         * call to usb_add_function() was successful. */
         * from this function.  So instead of incrementing counter now
         * and decrement in error recovery we increment it only when
         * call to usb_add_function() was successful. */
-       fsg->can_stall = common->can_stall;
 
        rc = usb_add_function(c, &fsg->function);
 
 
        rc = usb_add_function(c, &fsg->function);