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