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Diffstat (limited to 'drivers/usb/gadget/file_storage.c')
| -rw-r--r-- | drivers/usb/gadget/file_storage.c | 3676 |
1 files changed, 3676 insertions, 0 deletions
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c new file mode 100644 index 000000000000..a896d73f7a93 --- /dev/null +++ b/drivers/usb/gadget/file_storage.c @@ -0,0 +1,3676 @@ +/* + * file_storage.c -- File-backed USB Storage Gadget, for USB development + * + * Copyright (C) 2003-2008 Alan Stern + * 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 File-backed Storage Gadget 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 gadget driver for a USB + * device, it also illustrates a technique of double-buffering for increased + * throughput. Last but not least, it gives an easy way to probe the + * behavior of the Mass Storage drivers in a USB host. + * + * Backing storage is provided by a regular file or a block device, specified + * by the "file" module parameter. Access can be limited to read-only by + * setting the optional "ro" module parameter. (For CD-ROM emulation, + * access is always read-only.) The gadget will indicate that it has + * removable media if the optional "removable" module parameter is set. + * + * The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI), + * and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected + * by the optional "transport" module parameter. It also supports the + * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03), + * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by + * the optional "protocol" module parameter. In addition, the default + * Vendor ID, Product ID, release number and serial number can be overridden. + * + * There is support for multiple logical units (LUNs), each of which has + * its own backing file. The number of LUNs can be set using the optional + * "luns" module parameter (anywhere from 1 to 8), and the corresponding + * files are specified using comma-separated lists for "file" and "ro". + * The default number of LUNs is taken from the number of "file" elements; + * it is 1 if "file" is not given. If "removable" is not set then a backing + * file must be specified for each LUN. If it is set, then an unspecified + * or empty backing filename means the LUN's medium is not loaded. Ideally + * each LUN would be settable independently as a disk drive or a CD-ROM + * drive, but currently all LUNs have to be the same type. The CD-ROM + * emulation includes a single data track and no audio tracks; hence there + * need be only one backing file per LUN. + * + * Requirements are modest; only a bulk-in and a bulk-out endpoint are + * needed (an interrupt-out endpoint is also needed for CBI). The memory + * requirement amounts to two 16K buffers, size configurable by a parameter. + * Support is included for both full-speed and high-speed operation. + * + * Note that the driver is slightly non-portable in that it assumes a + * single memory/DMA buffer will be useable for bulk-in, bulk-out, and + * interrupt-in endpoints. With most device controllers this isn't an + * issue, but there may be some with hardware restrictions that prevent + * a buffer from being used by more than one endpoint. + * + * Module options: + * + * file=filename[,filename...] + * Required if "removable" is not set, names of + * the files or block devices used for + * backing storage + * serial=HHHH... Required serial number (string of hex chars) + * ro=b[,b...] Default false, booleans for read-only access + * removable Default false, boolean for removable media + * luns=N Default N = number of filenames, number of + * LUNs to support + * nofua=b[,b...] Default false, booleans for ignore FUA flag + * in SCSI WRITE(10,12) commands + * stall Default determined according to the type of + * USB device controller (usually true), + * boolean to permit the driver to halt + * bulk endpoints + * cdrom Default false, boolean for whether to emulate + * a CD-ROM drive + * transport=XXX Default BBB, transport name (CB, CBI, or BBB) + * protocol=YYY Default SCSI, protocol name (RBC, 8020 or + * ATAPI, QIC, UFI, 8070, or SCSI; + * also 1 - 6) + * vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID + * product=0xPPPP Default 0xa4a5 (FSG), USB Product ID + * release=0xRRRR Override the USB release number (bcdDevice) + * buflen=N Default N=16384, buffer size used (will be + * rounded down to a multiple of + * PAGE_CACHE_SIZE) + * + * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "serial", "ro", + * "removable", "luns", "nofua", "stall", and "cdrom" options are available; + * default values are used for everything else. + * + * The pathnames of the backing files and the ro settings are available in + * the attribute files "file", "nofua", and "ro" in the lun<n> subdirectory of + * the gadget's sysfs directory. If the "removable" option is set, writing to + * these files will simulate ejecting/loading the medium (writing an empty + * line means eject) and adjusting a write-enable tab. Changes to the ro + * setting are not allowed when the medium is loaded or if CD-ROM emulation + * is being used. + * + * This gadget driver 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 FSG driver 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. So just before the thread + * exits, it deregisters the gadget driver. This makes things a little + * tricky: The driver is deregistered at two places, and the exiting + * thread can indirectly call fsg_unbind() which in turn can tell the + * thread to exit. The first problem is resolved through the use of the + * REGISTERED atomic bitflag; the driver will only be deregistered once. + * The second problem is resolved by having fsg_unbind() check + * fsg->state; it won't try to stop the thread if the state is already + * FSG_STATE_TERMINATED. + * + * 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/module.h> +#include <linux/rwsem.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/string.h> +#include <linux/freezer.h> +#include <linux/utsname.h> + +#include <linux/usb/ch9.h> +#include <linux/usb/gadget.h> + +#include "gadget_chips.h" + + + +/* + * Kbuild is not very cooperative with respect to linking separately + * compiled library objects into one module. So for now we won't use + * separate compilation ... ensuring init/exit sections work to shrink + * the runtime footprint, and giving us at least some parts of what + * a "gcc --combine ... part1.c part2.c part3.c ... " build would. + */ +#include "usbstring.c" +#include "config.c" +#include "epautoconf.c" + +/*-------------------------------------------------------------------------*/ + +#define DRIVER_DESC "File-backed Storage Gadget" +#define DRIVER_NAME "g_file_storage" +#define DRIVER_VERSION "1 September 2010" + +static char fsg_string_manufacturer[64]; +static const char fsg_string_product[] = DRIVER_DESC; +static const char fsg_string_config[] = "Self-powered"; +static const char fsg_string_interface[] = "Mass Storage"; + + +#include "storage_common.c" + + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_AUTHOR("Alan Stern"); +MODULE_LICENSE("Dual BSD/GPL"); + +/* + * This driver assumes self-powered hardware and has no way for users to + * trigger remote wakeup. It uses autoconfiguration to select endpoints + * and endpoint addresses. + */ + + +/*-------------------------------------------------------------------------*/ + + +/* Encapsulate the module parameter settings */ + +static struct { + char *file[FSG_MAX_LUNS]; + char *serial; + bool ro[FSG_MAX_LUNS]; + bool nofua[FSG_MAX_LUNS]; + unsigned int num_filenames; + unsigned int num_ros; + unsigned int num_nofuas; + unsigned int nluns; + + bool removable; + bool can_stall; + bool cdrom; + + char *transport_parm; + char *protocol_parm; + unsigned short vendor; + unsigned short product; + unsigned short release; + unsigned int buflen; + + int transport_type; + char *transport_name; + int protocol_type; + char *protocol_name; + +} mod_data = { // Default values + .transport_parm = "BBB", + .protocol_parm = "SCSI", + .removable = 0, + .can_stall = 1, + .cdrom = 0, + .vendor = FSG_VENDOR_ID, + .product = FSG_PRODUCT_ID, + .release = 0xffff, // Use controller chip type + .buflen = 16384, + }; + + +module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames, + S_IRUGO); +MODULE_PARM_DESC(file, "names of backing files or devices"); + +module_param_named(serial, mod_data.serial, charp, S_IRUGO); +MODULE_PARM_DESC(serial, "USB serial number"); + +module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO); +MODULE_PARM_DESC(ro, "true to force read-only"); + +module_param_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas, + S_IRUGO); +MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit"); + +module_param_named(luns, mod_data.nluns, uint, S_IRUGO); +MODULE_PARM_DESC(luns, "number of LUNs"); + +module_param_named(removable, mod_data.removable, bool, S_IRUGO); +MODULE_PARM_DESC(removable, "true to simulate removable media"); + +module_param_named(stall, mod_data.can_stall, bool, S_IRUGO); +MODULE_PARM_DESC(stall, "false to prevent bulk stalls"); + +module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO); +MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk"); + +/* In the non-TEST version, only the module parameters listed above + * are available. */ +#ifdef CONFIG_USB_FILE_STORAGE_TEST + +module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO); +MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)"); + +module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO); +MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, " + "8070, or SCSI)"); + +module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO); +MODULE_PARM_DESC(vendor, "USB Vendor ID"); + +module_param_named(product, mod_data.product, ushort, S_IRUGO); +MODULE_PARM_DESC(product, "USB Product ID"); + +module_param_named(release, mod_data.release, ushort, S_IRUGO); +MODULE_PARM_DESC(release, "USB release number"); + +module_param_named(buflen, mod_data.buflen, uint, S_IRUGO); +MODULE_PARM_DESC(buflen, "I/O buffer size"); + +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + +/* + * These definitions will permit the compiler to avoid generating code for + * parts of the driver that aren't used in the non-TEST version. Even gcc + * can recognize when a test of a constant expression yields a dead code + * path. + */ + +#ifdef CONFIG_USB_FILE_STORAGE_TEST + +#define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK) +#define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI) +#define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI) + +#else + +#define transport_is_bbb() 1 +#define transport_is_cbi() 0 +#define protocol_is_scsi() 1 + +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + +/*-------------------------------------------------------------------------*/ + + +struct fsg_dev { + /* lock protects: state, all the req_busy's, and cbbuf_cmnd */ + spinlock_t lock; + struct usb_gadget *gadget; + + /* filesem protects: backing files in use */ + struct rw_semaphore filesem; + + /* reference counting: wait until all LUNs are released */ + struct kref ref; + + struct usb_ep *ep0; // Handy copy of gadget->ep0 + struct usb_request *ep0req; // For control responses + unsigned int ep0_req_tag; + const char *ep0req_name; + + struct usb_request *intreq; // For interrupt responses + int intreq_busy; + struct fsg_buffhd *intr_buffhd; + + unsigned int bulk_out_maxpacket; + enum fsg_state state; // For exception handling + unsigned int exception_req_tag; + + u8 config, new_config; + + unsigned int running : 1; + unsigned int bulk_in_enabled : 1; + unsigned int bulk_out_enabled : 1; + unsigned int intr_in_enabled : 1; + unsigned int phase_error : 1; + unsigned int short_packet_received : 1; + unsigned int bad_lun_okay : 1; + + unsigned long atomic_bitflags; +#define REGISTERED 0 +#define IGNORE_BULK_OUT 1 +#define SUSPENDED 2 + + struct usb_ep *bulk_in; + struct usb_ep *bulk_out; + struct usb_ep *intr_in; + + struct fsg_buffhd *next_buffhd_to_fill; + struct fsg_buffhd *next_buffhd_to_drain; + + int thread_wakeup_needed; + struct completion thread_notifier; + struct task_struct *thread_task; + + int cmnd_size; + u8 cmnd[MAX_COMMAND_SIZE]; + enum data_direction data_dir; + u32 data_size; + u32 data_size_from_cmnd; + u32 tag; + unsigned int lun; + u32 residue; + u32 usb_amount_left; + + /* The CB protocol offers no way for a host to know when a command + * has completed. As a result the next command may arrive early, + * and we will still have to handle it. For that reason we need + * a buffer to store new commands when using CB (or CBI, which + * does not oblige a host to wait for command completion either). */ + int cbbuf_cmnd_size; + u8 cbbuf_cmnd[MAX_COMMAND_SIZE]; + + unsigned int nluns; + struct fsg_lun *luns; + struct fsg_lun *curlun; + /* Must be the last entry */ + struct fsg_buffhd buffhds[]; +}; + +typedef void (*fsg_routine_t)(struct fsg_dev *); + +static int exception_in_progress(struct fsg_dev *fsg) +{ + return (fsg->state > FSG_STATE_IDLE); +} + +/* Make bulk-out requests be divisible by the maxpacket size */ +static void set_bulk_out_req_length(struct fsg_dev *fsg, + struct fsg_buffhd *bh, unsigned int length) +{ + unsigned int rem; + + bh->bulk_out_intended_length = length; + rem = length % fsg->bulk_out_maxpacket; + if (rem > 0) + length += fsg->bulk_out_maxpacket - rem; + bh->outreq->length = length; +} + +static struct fsg_dev *the_fsg; +static struct usb_gadget_driver fsg_driver; + + +/*-------------------------------------------------------------------------*/ + +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); +} + + +/*-------------------------------------------------------------------------*/ + +/* + * DESCRIPTORS ... most are static, but strings and (full) configuration + * descriptors are built on demand. Also the (static) config and interface + * descriptors are adjusted during fsg_bind(). + */ + +/* There is only one configuration. */ +#define CONFIG_VALUE 1 + +static struct usb_device_descriptor +device_desc = { + .bLength = sizeof device_desc, + .bDescriptorType = USB_DT_DEVICE, + + .bcdUSB = cpu_to_le16(0x0200), + .bDeviceClass = USB_CLASS_PER_INTERFACE, + + /* The next three values can be overridden by module parameters */ + .idVendor = cpu_to_le16(FSG_VENDOR_ID), + .idProduct = cpu_to_le16(FSG_PRODUCT_ID), + .bcdDevice = cpu_to_le16(0xffff), + + .iManufacturer = FSG_STRING_MANUFACTURER, + .iProduct = FSG_STRING_PRODUCT, + .iSerialNumber = FSG_STRING_SERIAL, + .bNumConfigurations = 1, +}; + +static struct usb_config_descriptor +config_desc = { + .bLength = sizeof config_desc, + .bDescriptorType = USB_DT_CONFIG, + + /* wTotalLength computed by usb_gadget_config_buf() */ + .bNumInterfaces = 1, + .bConfigurationValue = CONFIG_VALUE, + .iConfiguration = FSG_STRING_CONFIG, + .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER, + .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2, +}; + + +static struct usb_qualifier_descriptor +dev_qualifier = { + .bLength = sizeof dev_qualifier, + .bDescriptorType = USB_DT_DEVICE_QUALIFIER, + + .bcdUSB = cpu_to_le16(0x0200), + .bDeviceClass = USB_CLASS_PER_INTERFACE, + + .bNumConfigurations = 1, +}; + +static int populate_bos(struct fsg_dev *fsg, u8 *buf) +{ + memcpy(buf, &fsg_bos_desc, USB_DT_BOS_SIZE); + buf += USB_DT_BOS_SIZE; + + memcpy(buf, &fsg_ext_cap_desc, USB_DT_USB_EXT_CAP_SIZE); + buf += USB_DT_USB_EXT_CAP_SIZE; + + memcpy(buf, &fsg_ss_cap_desc, USB_DT_USB_SS_CAP_SIZE); + + return USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE + + USB_DT_USB_EXT_CAP_SIZE; +} + +/* + * Config descriptors must agree with the code that sets configurations + * and with code managing interfaces and their altsettings. They must + * also handle different speeds and other-speed requests. + */ +static int populate_config_buf(struct usb_gadget *gadget, + u8 *buf, u8 type, unsigned index) +{ + enum usb_device_speed speed = gadget->speed; + int len; + const struct usb_descriptor_header **function; + + if (index > 0) + return -EINVAL; + + if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG) + speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed; + function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH + ? (const struct usb_descriptor_header **)fsg_hs_function + : (const struct usb_descriptor_header **)fsg_fs_function; + + /* for now, don't advertise srp-only devices */ + if (!gadget_is_otg(gadget)) + function++; + + len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function); + ((struct usb_config_descriptor *) buf)->bDescriptorType = type; + return len; +} + + +/*-------------------------------------------------------------------------*/ + +/* These routines may be called in process context or in_irq */ + +/* Caller must hold fsg->lock */ +static void wakeup_thread(struct fsg_dev *fsg) +{ + /* Tell the main thread that something has happened */ + fsg->thread_wakeup_needed = 1; + if (fsg->thread_task) + wake_up_process(fsg->thread_task); +} + + +static void raise_exception(struct fsg_dev *fsg, 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(&fsg->lock, flags); + if (fsg->state <= new_state) { + fsg->exception_req_tag = fsg->ep0_req_tag; + fsg->state = new_state; + if (fsg->thread_task) + send_sig_info(SIGUSR1, SEND_SIG_FORCED, + fsg->thread_task); + } + spin_unlock_irqrestore(&fsg->lock, flags); +} + + +/*-------------------------------------------------------------------------*/ + +/* The disconnect callback and ep0 routines. These always run in_irq, + * except that ep0_queue() is called in the main thread to acknowledge + * completion of various requests: set config, set interface, and + * Bulk-only device reset. */ + +static void fsg_disconnect(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + + DBG(fsg, "disconnect or port reset\n"); + raise_exception(fsg, FSG_STATE_DISCONNECT); +} + + +static int ep0_queue(struct fsg_dev *fsg) +{ + int rc; + + rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC); + if (rc != 0 && rc != -ESHUTDOWN) { + + /* We can't do much more than wait for a reset */ + WARNING(fsg, "error in submission: %s --> %d\n", + fsg->ep0->name, rc); + } + return rc; +} + +static void ep0_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = ep->driver_data; + + if (req->actual > 0) + dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual); + if (req->status || req->actual != req->length) + DBG(fsg, "%s --> %d, %u/%u\n", __func__, + req->status, req->actual, req->length); + if (req->status == -ECONNRESET) // Request was cancelled + usb_ep_fifo_flush(ep); + + if (req->status == 0 && req->context) + ((fsg_routine_t) (req->context))(fsg); +} + + +/*-------------------------------------------------------------------------*/ + +/* Bulk and interrupt endpoint completion handlers. + * These always run in_irq. */ + +static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = ep->driver_data; + struct fsg_buffhd *bh = req->context; + + if (req->status || req->actual != req->length) + DBG(fsg, "%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(&fsg->lock); + bh->inreq_busy = 0; + bh->state = BUF_STATE_EMPTY; + wakeup_thread(fsg); + spin_unlock(&fsg->lock); +} + +static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = ep->driver_data; + struct fsg_buffhd *bh = req->context; + + dump_msg(fsg, "bulk-out", req->buf, req->actual); + if (req->status || req->actual != bh->bulk_out_intended_length) + DBG(fsg, "%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(&fsg->lock); + bh->outreq_busy = 0; + bh->state = BUF_STATE_FULL; + wakeup_thread(fsg); + spin_unlock(&fsg->lock); +} + + +#ifdef CONFIG_USB_FILE_STORAGE_TEST +static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = ep->driver_data; + struct fsg_buffhd *bh = req->context; + + if (req->status || req->actual != req->length) + DBG(fsg, "%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(&fsg->lock); + fsg->intreq_busy = 0; + bh->state = BUF_STATE_EMPTY; + wakeup_thread(fsg); + spin_unlock(&fsg->lock); +} + +#else +static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) +{} +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + +/*-------------------------------------------------------------------------*/ + +/* Ep0 class-specific handlers. These always run in_irq. */ + +#ifdef CONFIG_USB_FILE_STORAGE_TEST +static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{ + struct usb_request *req = fsg->ep0req; + static u8 cbi_reset_cmnd[6] = { + SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff}; + + /* Error in command transfer? */ + if (req->status || req->length != req->actual || + req->actual < 6 || req->actual > MAX_COMMAND_SIZE) { + + /* Not all controllers allow a protocol stall after + * receiving control-out data, but we'll try anyway. */ + fsg_set_halt(fsg, fsg->ep0); + return; // Wait for reset + } + + /* Is it the special reset command? */ + if (req->actual >= sizeof cbi_reset_cmnd && + memcmp(req->buf, cbi_reset_cmnd, + sizeof cbi_reset_cmnd) == 0) { + + /* Raise an exception to stop the current operation + * and reinitialize our state. */ + DBG(fsg, "cbi reset request\n"); + raise_exception(fsg, FSG_STATE_RESET); + return; + } + + VDBG(fsg, "CB[I] accept device-specific command\n"); + spin_lock(&fsg->lock); + + /* Save the command for later */ + if (fsg->cbbuf_cmnd_size) + WARNING(fsg, "CB[I] overwriting previous command\n"); + fsg->cbbuf_cmnd_size = req->actual; + memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size); + + wakeup_thread(fsg); + spin_unlock(&fsg->lock); +} + +#else +static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{} +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + +static int class_setup_req(struct fsg_dev *fsg, + const struct usb_ctrlrequest *ctrl) +{ + struct usb_request *req = fsg->ep0req; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + u16 w_length = le16_to_cpu(ctrl->wLength); + + if (!fsg->config) + return value; + + /* Handle Bulk-only class-specific requests */ + if (transport_is_bbb()) { + switch (ctrl->bRequest) { + + case US_BULK_RESET_REQUEST: + if (ctrl->bRequestType != (USB_DIR_OUT | + USB_TYPE_CLASS | USB_RECIP_INTERFACE)) + break; + if (w_index != 0 || w_value != 0 || w_length != 0) { + value = -EDOM; + break; + } + + /* Raise an exception to stop the current operation + * and reinitialize our state. */ + DBG(fsg, "bulk reset request\n"); + raise_exception(fsg, FSG_STATE_RESET); + value = DELAYED_STATUS; + break; + + case US_BULK_GET_MAX_LUN: + if (ctrl->bRequestType != (USB_DIR_IN | + USB_TYPE_CLASS | USB_RECIP_INTERFACE)) + break; + if (w_index != 0 || w_value != 0 || w_length != 1) { + value = -EDOM; + break; + } + VDBG(fsg, "get max LUN\n"); + *(u8 *) req->buf = fsg->nluns - 1; + value = 1; + break; + } + } + + /* Handle CBI class-specific requests */ + else { + switch (ctrl->bRequest) { + + case USB_CBI_ADSC_REQUEST: + if (ctrl->bRequestType != (USB_DIR_OUT | + USB_TYPE_CLASS | USB_RECIP_INTERFACE)) + break; + if (w_index != 0 || w_value != 0) { + value = -EDOM; + break; + } + if (w_length > MAX_COMMAND_SIZE) { + value = -EOVERFLOW; + break; + } + value = w_length; + fsg->ep0req->context = received_cbi_adsc; + break; + } + } + + if (value == -EOPNOTSUPP) + 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 value; +} + + +/*-------------------------------------------------------------------------*/ + +/* Ep0 standard request handlers. These always run in_irq. */ + +static int standard_setup_req(struct fsg_dev *fsg, + const struct usb_ctrlrequest *ctrl) +{ + struct usb_request *req = fsg->ep0req; + int value = -EOPNOTSUPP; + u16 w_index = le16_to_cpu(ctrl->wIndex); + u16 w_value = le16_to_cpu(ctrl->wValue); + + /* Usually this just stores reply data in the pre-allocated ep0 buffer, + * but config change events will also reconfigure hardware. */ + switch (ctrl->bRequest) { + + case USB_REQ_GET_DESCRIPTOR: + if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | + USB_RECIP_DEVICE)) + break; + switch (w_value >> 8) { + + case USB_DT_DEVICE: + VDBG(fsg, "get device descriptor\n"); + device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket; + value = sizeof device_desc; + memcpy(req->buf, &device_desc, value); + break; + case USB_DT_DEVICE_QUALIFIER: + VDBG(fsg, "get device qualifier\n"); + if (!gadget_is_dualspeed(fsg->gadget) || + fsg->gadget->speed == USB_SPEED_SUPER) + break; + /* + * Assume ep0 uses the same maxpacket value for both + * speeds + */ + dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket; + value = sizeof dev_qualifier; + memcpy(req->buf, &dev_qualifier, value); + break; + + case USB_DT_OTHER_SPEED_CONFIG: + VDBG(fsg, "get other-speed config descriptor\n"); + if (!gadget_is_dualspeed(fsg->gadget) || + fsg->gadget->speed == USB_SPEED_SUPER) + break; + goto get_config; + case USB_DT_CONFIG: + VDBG(fsg, "get configuration descriptor\n"); +get_config: + value = populate_config_buf(fsg->gadget, + req->buf, + w_value >> 8, + w_value & 0xff); + break; + + case USB_DT_STRING: + VDBG(fsg, "get string descriptor\n"); + + /* wIndex == language code */ + value = usb_gadget_get_string(&fsg_stringtab, + w_value & 0xff, req->buf); + break; + + case USB_DT_BOS: + VDBG(fsg, "get bos descriptor\n"); + + if (gadget_is_superspeed(fsg->gadget)) + value = populate_bos(fsg, req->buf); + break; + } + + break; + + /* One config, two speeds */ + case USB_REQ_SET_CONFIGURATION: + if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD | + USB_RECIP_DEVICE)) + break; + VDBG(fsg, "set configuration\n"); + if (w_value == CONFIG_VALUE || w_value == 0) { + fsg->new_config = w_value; + + /* Raise an exception to wipe out previous transaction + * state (queued bufs, etc) and set the new config. */ + raise_exception(fsg, FSG_STATE_CONFIG_CHANGE); + value = DELAYED_STATUS; + } + break; + case USB_REQ_GET_CONFIGURATION: + if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | + USB_RECIP_DEVICE)) + break; + VDBG(fsg, "get configuration\n"); + *(u8 *) req->buf = fsg->config; + value = 1; + break; + + case USB_REQ_SET_INTERFACE: + if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD | + USB_RECIP_INTERFACE)) + break; + if (fsg->config && w_index == 0) { + + /* Raise an exception to wipe out previous transaction + * state (queued bufs, etc) and install the new + * interface altsetting. */ + raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE); + value = DELAYED_STATUS; + } + break; + case USB_REQ_GET_INTERFACE: + if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | + USB_RECIP_INTERFACE)) + break; + if (!fsg->config) + break; + if (w_index != 0) { + value = -EDOM; + break; + } + VDBG(fsg, "get interface\n"); + *(u8 *) req->buf = 0; + value = 1; + break; + + default: + VDBG(fsg, + "unknown control req %02x.%02x v%04x i%04x l%u\n", + ctrl->bRequestType, ctrl->bRequest, + w_value, w_index, le16_to_cpu(ctrl->wLength)); + } + + return value; +} + + +static int fsg_setup(struct usb_gadget *gadget, + const struct usb_ctrlrequest *ctrl) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + int rc; + int w_length = le16_to_cpu(ctrl->wLength); + + ++fsg->ep0_req_tag; // Record arrival of a new request + fsg->ep0req->context = NULL; + fsg->ep0req->length = 0; + dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl)); + + if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) + rc = class_setup_req(fsg, ctrl); + else + rc = standard_setup_req(fsg, ctrl); + + /* Respond with data/status or defer until later? */ + if (rc >= 0 && rc != DELAYED_STATUS) { + rc = min(rc, w_length); + fsg->ep0req->length = rc; + fsg->ep0req->zero = rc < w_length; + fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ? + "ep0-in" : "ep0-out"); + rc = ep0_queue(fsg); + } + + /* Device either stalls (rc < 0) or reports success */ + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +/* 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); + else if (ep == fsg->intr_in) + dump_msg(fsg, "intr-in", req->buf, req->length); + + spin_lock_irq(&fsg->lock); + *pbusy = 1; + *state = BUF_STATE_BUSY; + spin_unlock_irq(&fsg->lock); + rc = usb_ep_queue(ep, req, GFP_KERNEL); + if (rc != 0) { + *pbusy = 0; + *state = BUF_STATE_EMPTY; + + /* We can't do much more than wait for a reset */ + + /* Note: currently the net2280 driver fails zero-length + * submissions if DMA is enabled. */ + if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP && + req->length == 0)) + WARNING(fsg, "error in submission: %s --> %d\n", + ep->name, rc); + } +} + + +static int sleep_thread(struct fsg_dev *fsg) +{ + int rc = 0; + + /* Wait until a signal arrives or we are woken up */ + for (;;) { + try_to_freeze(); + set_current_state(TASK_INTERRUPTIBLE); + if (signal_pending(current)) { + rc = -EINTR; + break; + } + if (fsg->thread_wakeup_needed) + break; + schedule(); + } + __set_current_state(TASK_RUNNING); + fsg->thread_wakeup_needed = 0; + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static int do_read(struct fsg_dev *fsg) +{ + struct fsg_lun *curlun = fsg->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 (fsg->cmnd[0] == READ_6) + lba = get_unaligned_be24(&fsg->cmnd[1]); + else { + lba = get_unaligned_be32(&fsg->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 ((fsg->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 = fsg->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((unsigned int) amount_left, mod_data.buflen); + amount = min((loff_t) amount, + curlun->file_length - file_offset); + + /* Wait for the next buffer to become available */ + bh = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + rc = sleep_thread(fsg); + 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; + fsg->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; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + } + + return -EIO; // No default reply +} + + +/*-------------------------------------------------------------------------*/ + +static int do_write(struct fsg_dev *fsg) +{ + struct fsg_lun *curlun = fsg->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 (fsg->cmnd[0] == WRITE_6) + lba = get_unaligned_be24(&fsg->cmnd[1]); + else { + lba = get_unaligned_be32(&fsg->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 ((fsg->cmnd[1] & ~0x18) != 0) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + /* FUA */ + if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) { + spin_lock(&curlun->filp->f_lock); + curlun->filp->f_flags |= O_DSYNC; + 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 = amount_left_to_write = fsg->data_size_from_cmnd; + + while (amount_left_to_write > 0) { + + /* Queue a request for more data from the host */ + bh = fsg->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, mod_data.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; + fsg->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(fsg, bh, amount); + start_transfer(fsg, fsg->bulk_out, bh->outreq, + &bh->outreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + continue; + } + + /* Write the received data to the backing file */ + bh = fsg->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(); + fsg->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; + fsg->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) { + fsg->short_packet_received = 1; + break; + } + continue; + } + + /* Wait for something to happen */ + rc = sleep_thread(fsg); + if (rc) + return rc; + } + + return -EIO; // No default reply +} + + +/*-------------------------------------------------------------------------*/ + +static int do_synchronize_cache(struct fsg_dev *fsg) +{ + struct fsg_lun *curlun = fsg->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 = filp->f_path.dentry->d_inode; + 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_dev *fsg) +{ + struct fsg_lun *curlun = fsg->curlun; + u32 lba; + u32 verification_length; + struct fsg_buffhd *bh = fsg->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(&fsg->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 ((fsg->cmnd[1] & ~0x10) != 0) { + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + verification_length = get_unaligned_be16(&fsg->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((unsigned int) amount_left, mod_data.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_dev *fsg, struct fsg_buffhd *bh) +{ + u8 *buf = (u8 *) bh->buf; + + static char vendor_id[] = "Linux "; + static char product_disk_id[] = "File-Stor Gadget"; + static char product_cdrom_id[] = "File-CD Gadget "; + + if (!fsg->curlun) { // Unsupported LUNs are okay + fsg->bad_lun_okay = 1; + memset(buf, 0, 36); + buf[0] = 0x7f; // Unsupported, no device-type + buf[4] = 31; // Additional length + return 36; + } + + memset(buf, 0, 8); + buf[0] = (mod_data.cdrom ? TYPE_ROM : TYPE_DISK); + if (mod_data.removable) + buf[1] = 0x80; + buf[2] = 2; // ANSI SCSI level 2 + buf[3] = 2; // SCSI-2 INQUIRY data format + buf[4] = 31; // Additional length + // No special options + sprintf(buf + 8, "%-8s%-16s%04x", vendor_id, + (mod_data.cdrom ? product_cdrom_id : + product_disk_id), + mod_data.release); + return 36; +} + + +static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->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 + fsg->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_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->curlun; + u32 lba = get_unaligned_be32(&fsg->cmnd[2]); + int pmi = fsg->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_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->curlun; + int msf = fsg->cmnd[1] & 0x02; + u32 lba = get_unaligned_be32(&fsg->cmnd[2]); + u8 *buf = (u8 *) bh->buf; + + if ((fsg->cmnd[1] & ~0x02) != 0) { /* 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_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->curlun; + int msf = fsg->cmnd[1] & 0x02; + int start_track = fsg->cmnd[6]; + u8 *buf = (u8 *) bh->buf; + + if ((fsg->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_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->curlun; + int mscmnd = fsg->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 ((fsg->cmnd[1] & ~0x08) != 0) { // Mask away DBD + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + pc = fsg->cmnd[2] >> 6; + page_code = fsg->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 mod_data.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_dev *fsg) +{ + struct fsg_lun *curlun = fsg->curlun; + int loej, start; + + if (!mod_data.removable) { + curlun->sense_data = SS_INVALID_COMMAND; + return -EINVAL; + } + + // int immed = fsg->cmnd[1] & 0x01; + loej = fsg->cmnd[4] & 0x02; + start = fsg->cmnd[4] & 0x01; + +#ifdef CONFIG_USB_FILE_STORAGE_TEST + if ((fsg->cmnd[1] & ~0x01) != 0 || // Mask away Immed + (fsg->cmnd[4] & ~0x03) != 0) { // Mask LoEj, Start + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } + + if (!start) { + + /* 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) { // Simulate an unload/eject + up_read(&fsg->filesem); + down_write(&fsg->filesem); + fsg_lun_close(curlun); + up_write(&fsg->filesem); + down_read(&fsg->filesem); + } + } else { + + /* Our emulation doesn't support mounting; the medium is + * available for use as soon as it is loaded. */ + if (!fsg_lun_is_open(curlun)) { + curlun->sense_data = SS_MEDIUM_NOT_PRESENT; + return -EINVAL; + } + } +#endif + return 0; +} + + +static int do_prevent_allow(struct fsg_dev *fsg) +{ + struct fsg_lun *curlun = fsg->curlun; + int prevent; + + if (!mod_data.removable) { + curlun->sense_data = SS_INVALID_COMMAND; + return -EINVAL; + } + + prevent = fsg->cmnd[4] & 0x01; + if ((fsg->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_dev *fsg, + struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->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_dev *fsg, struct fsg_buffhd *bh) +{ + struct fsg_lun *curlun = fsg->curlun; + + /* We don't support MODE SELECT */ + 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_dev *fsg) +{ + struct fsg_buffhd *bh; + u32 amount; + int rc; + + while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY || + fsg->usb_amount_left > 0) { + + /* Throw away the data in a filled buffer */ + if (bh->state == BUF_STATE_FULL) { + smp_rmb(); + bh->state = BUF_STATE_EMPTY; + fsg->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(fsg, FSG_STATE_ABORT_BULK_OUT); + return -EINTR; + } + continue; + } + + /* Try to submit another request if we need one */ + bh = fsg->next_buffhd_to_fill; + if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) { + amount = min(fsg->usb_amount_left, + (u32) mod_data.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(fsg, bh, amount); + start_transfer(fsg, fsg->bulk_out, bh->outreq, + &bh->outreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + fsg->usb_amount_left -= amount; + continue; + } + + /* Otherwise wait for something to happen */ + rc = sleep_thread(fsg); + if (rc) + return rc; + } + return 0; +} + + +static int finish_reply(struct fsg_dev *fsg) +{ + struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; + int rc = 0; + + switch (fsg->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 (mod_data.can_stall) { + fsg_set_halt(fsg, fsg->bulk_out); + rc = halt_bulk_in_endpoint(fsg); + } + break; + + /* All but the last buffer of data must have already been sent */ + case DATA_DIR_TO_HOST: + if (fsg->data_size == 0) + ; // Nothing to send + + /* If there's no residue, simply send the last buffer */ + else if (fsg->residue == 0) { + bh->inreq->zero = 0; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + } + + /* There is a residue. For CB and CBI, simply mark the end + * of the data with a short packet. However, if we are + * allowed to stall, there was no data at all (residue == + * data_size), and the command failed (invalid LUN or + * sense data is set), then halt the bulk-in endpoint + * instead. */ + else if (!transport_is_bbb()) { + if (mod_data.can_stall && + fsg->residue == fsg->data_size && + (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) { + bh->state = BUF_STATE_EMPTY; + rc = halt_bulk_in_endpoint(fsg); + } else { + bh->inreq->zero = 1; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + fsg->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; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + if (mod_data.can_stall) + rc = halt_bulk_in_endpoint(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 (fsg->residue == 0) + ; // Nothing to receive + + /* Did the host stop sending unexpectedly early? */ + else if (fsg->short_packet_received) { + raise_exception(fsg, 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 (mod_data.can_stall) { + fsg_set_halt(fsg, fsg->bulk_out); + raise_exception(fsg, 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(fsg); + break; + } + return rc; +} + + +static int send_status(struct fsg_dev *fsg) +{ + struct fsg_lun *curlun = fsg->curlun; + struct fsg_buffhd *bh; + int rc; + u8 status = US_BULK_STAT_OK; + u32 sd, sdinfo = 0; + + /* Wait for the next buffer to become available */ + bh = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + rc = sleep_thread(fsg); + if (rc) + return rc; + } + + if (curlun) { + sd = curlun->sense_data; + sdinfo = curlun->sense_data_info; + } else if (fsg->bad_lun_okay) + sd = SS_NO_SENSE; + else + sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; + + if (fsg->phase_error) { + DBG(fsg, "sending phase-error status\n"); + status = US_BULK_STAT_PHASE; + sd = SS_INVALID_COMMAND; + } else if (sd != SS_NO_SENSE) { + DBG(fsg, "sending command-failure status\n"); + status = US_BULK_STAT_FAIL; + VDBG(fsg, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;" + " info x%x\n", + SK(sd), ASC(sd), ASCQ(sd), sdinfo); + } + + if (transport_is_bbb()) { + struct bulk_cs_wrap *csw = bh->buf; + + /* Store and send the Bulk-only CSW */ + csw->Signature = cpu_to_le32(US_BULK_CS_SIGN); + csw->Tag = fsg->tag; + csw->Residue = cpu_to_le32(fsg->residue); + csw->Status = status; + + bh->inreq->length = US_BULK_CS_WRAP_LEN; + bh->inreq->zero = 0; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + + } else if (mod_data.transport_type == USB_PR_CB) { + + /* Control-Bulk transport has no status phase! */ + return 0; + + } else { // USB_PR_CBI + struct interrupt_data *buf = bh->buf; + + /* Store and send the Interrupt data. UFI sends the ASC + * and ASCQ bytes. Everything else sends a Type (which + * is always 0) and the status Value. */ + if (mod_data.protocol_type == USB_SC_UFI) { + buf->bType = ASC(sd); + buf->bValue = ASCQ(sd); + } else { + buf->bType = 0; + buf->bValue = status; + } + fsg->intreq->length = CBI_INTERRUPT_DATA_LEN; + + fsg->intr_buffhd = bh; // Point to the right buffhd + fsg->intreq->buf = bh->inreq->buf; + fsg->intreq->context = bh; + start_transfer(fsg, fsg->intr_in, fsg->intreq, + &fsg->intreq_busy, &bh->state); + } + + fsg->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_dev *fsg, int cmnd_size, + enum data_direction data_dir, unsigned int mask, + int needs_medium, const char *name) +{ + int i; + int lun = fsg->cmnd[1] >> 5; + static const char dirletter[4] = {'u', 'o', 'i', 'n'}; + char hdlen[20]; + struct fsg_lun *curlun; + + /* Adjust the expected cmnd_size for protocol encapsulation padding. + * Transparent SCSI doesn't pad. */ + if (protocol_is_scsi()) + ; + + /* There's some disagreement as to whether RBC pads commands or not. + * We'll play it safe and accept either form. */ + else if (mod_data.protocol_type == USB_SC_RBC) { + if (fsg->cmnd_size == 12) + cmnd_size = 12; + + /* All the other protocols pad to 12 bytes */ + } else + cmnd_size = 12; + + hdlen[0] = 0; + if (fsg->data_dir != DATA_DIR_UNKNOWN) + sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir], + fsg->data_size); + VDBG(fsg, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n", + name, cmnd_size, dirletter[(int) data_dir], + fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen); + + /* We can't reply at all until we know the correct data direction + * and size. */ + if (fsg->data_size_from_cmnd == 0) + data_dir = DATA_DIR_NONE; + if (fsg->data_dir == DATA_DIR_UNKNOWN) { // CB or CBI + fsg->data_dir = data_dir; + fsg->data_size = fsg->data_size_from_cmnd; + + } else { // Bulk-only + if (fsg->data_size < fsg->data_size_from_cmnd) { + + /* Host data size < Device data size is a phase error. + * Carry out the command, but only transfer as much + * as we are allowed. */ + fsg->data_size_from_cmnd = fsg->data_size; + fsg->phase_error = 1; + } + } + fsg->residue = fsg->usb_amount_left = fsg->data_size; + + /* Conflicting data directions is a phase error */ + if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) { + fsg->phase_error = 1; + return -EINVAL; + } + + /* Verify the length of the command itself */ + if (cmnd_size != fsg->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 <= fsg->cmnd_size) { + DBG(fsg, "%s is buggy! Expected length %d " + "but we got %d\n", name, + cmnd_size, fsg->cmnd_size); + cmnd_size = fsg->cmnd_size; + } else { + fsg->phase_error = 1; + return -EINVAL; + } + } + + /* Check that the LUN values are consistent */ + if (transport_is_bbb()) { + if (fsg->lun != lun) + DBG(fsg, "using LUN %d from CBW, " + "not LUN %d from CDB\n", + fsg->lun, lun); + } + + /* Check the LUN */ + curlun = fsg->curlun; + if (curlun) { + if (fsg->cmnd[0] != REQUEST_SENSE) { + curlun->sense_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + curlun->info_valid = 0; + } + } else { + fsg->bad_lun_okay = 0; + + /* INQUIRY and REQUEST SENSE commands are explicitly allowed + * to use unsupported LUNs; all others may not. */ + if (fsg->cmnd[0] != INQUIRY && + fsg->cmnd[0] != REQUEST_SENSE) { + DBG(fsg, "unsupported LUN %d\n", fsg->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 && + fsg->cmnd[0] != INQUIRY && + fsg->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 */ + fsg->cmnd[1] &= 0x1f; // Mask away the LUN + for (i = 1; i < cmnd_size; ++i) { + if (fsg->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_dev *fsg, int cmnd_size, + enum data_direction data_dir, unsigned int mask, + int needs_medium, const char *name) +{ + if (fsg->curlun) + fsg->data_size_from_cmnd <<= fsg->curlun->blkbits; + return check_command(fsg, cmnd_size, data_dir, + mask, needs_medium, name); +} + +static int do_scsi_command(struct fsg_dev *fsg) +{ + struct fsg_buffhd *bh; + int rc; + int reply = -EINVAL; + int i; + static char unknown[16]; + + dump_cdb(fsg); + + /* Wait for the next buffer to become available for data or status */ + bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + rc = sleep_thread(fsg); + if (rc) + return rc; + } + fsg->phase_error = 0; + fsg->short_packet_received = 0; + + down_read(&fsg->filesem); // We're using the backing file + switch (fsg->cmnd[0]) { + + case INQUIRY: + fsg->data_size_from_cmnd = fsg->cmnd[4]; + if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<4), 0, + "INQUIRY")) == 0) + reply = do_inquiry(fsg, bh); + break; + + case MODE_SELECT: + fsg->data_size_from_cmnd = fsg->cmnd[4]; + if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, + (1<<1) | (1<<4), 0, + "MODE SELECT(6)")) == 0) + reply = do_mode_select(fsg, bh); + break; + + case MODE_SELECT_10: + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, + (1<<1) | (3<<7), 0, + "MODE SELECT(10)")) == 0) + reply = do_mode_select(fsg, bh); + break; + + case MODE_SENSE: + fsg->data_size_from_cmnd = fsg->cmnd[4]; + if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<1) | (1<<2) | (1<<4), 0, + "MODE SENSE(6)")) == 0) + reply = do_mode_sense(fsg, bh); + break; + + case MODE_SENSE_10: + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (1<<1) | (1<<2) | (3<<7), 0, + "MODE SENSE(10)")) == 0) + reply = do_mode_sense(fsg, bh); + break; + + case ALLOW_MEDIUM_REMOVAL: + fsg->data_size_from_cmnd = 0; + if ((reply = check_command(fsg, 6, DATA_DIR_NONE, + (1<<4), 0, + "PREVENT-ALLOW MEDIUM REMOVAL")) == 0) + reply = do_prevent_allow(fsg); + break; + + case READ_6: + i = fsg->cmnd[4]; + fsg->data_size_from_cmnd = (i == 0) ? 256 : i; + if ((reply = check_command_size_in_blocks(fsg, 6, + DATA_DIR_TO_HOST, + (7<<1) | (1<<4), 1, + "READ(6)")) == 0) + reply = do_read(fsg); + break; + + case READ_10: + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command_size_in_blocks(fsg, 10, + DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "READ(10)")) == 0) + reply = do_read(fsg); + break; + + case READ_12: + fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->cmnd[6]); + if ((reply = check_command_size_in_blocks(fsg, 12, + DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "READ(12)")) == 0) + reply = do_read(fsg); + break; + + case READ_CAPACITY: + fsg->data_size_from_cmnd = 8; + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (0xf<<2) | (1<<8), 1, + "READ CAPACITY")) == 0) + reply = do_read_capacity(fsg, bh); + break; + + case READ_HEADER: + if (!mod_data.cdrom) + goto unknown_cmnd; + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (3<<7) | (0x1f<<1), 1, + "READ HEADER")) == 0) + reply = do_read_header(fsg, bh); + break; + + case READ_TOC: + if (!mod_data.cdrom) + goto unknown_cmnd; + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (7<<6) | (1<<1), 1, + "READ TOC")) == 0) + reply = do_read_toc(fsg, bh); + break; + + case READ_FORMAT_CAPACITIES: + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (3<<7), 1, + "READ FORMAT CAPACITIES")) == 0) + reply = do_read_format_capacities(fsg, bh); + break; + + case REQUEST_SENSE: + fsg->data_size_from_cmnd = fsg->cmnd[4]; + if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (1<<4), 0, + "REQUEST SENSE")) == 0) + reply = do_request_sense(fsg, bh); + break; + + case START_STOP: + fsg->data_size_from_cmnd = 0; + if ((reply = check_command(fsg, 6, DATA_DIR_NONE, + (1<<1) | (1<<4), 0, + "START-STOP UNIT")) == 0) + reply = do_start_stop(fsg); + break; + + case SYNCHRONIZE_CACHE: + fsg->data_size_from_cmnd = 0; + if ((reply = check_command(fsg, 10, DATA_DIR_NONE, + (0xf<<2) | (3<<7), 1, + "SYNCHRONIZE CACHE")) == 0) + reply = do_synchronize_cache(fsg); + break; + + case TEST_UNIT_READY: + fsg->data_size_from_cmnd = 0; + reply = check_command(fsg, 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: + fsg->data_size_from_cmnd = 0; + if ((reply = check_command(fsg, 10, DATA_DIR_NONE, + (1<<1) | (0xf<<2) | (3<<7), 1, + "VERIFY")) == 0) + reply = do_verify(fsg); + break; + + case WRITE_6: + i = fsg->cmnd[4]; + fsg->data_size_from_cmnd = (i == 0) ? 256 : i; + if ((reply = check_command_size_in_blocks(fsg, 6, + DATA_DIR_FROM_HOST, + (7<<1) | (1<<4), 1, + "WRITE(6)")) == 0) + reply = do_write(fsg); + break; + + case WRITE_10: + fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); + if ((reply = check_command_size_in_blocks(fsg, 10, + DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "WRITE(10)")) == 0) + reply = do_write(fsg); + break; + + case WRITE_12: + fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->cmnd[6]); + if ((reply = check_command_size_in_blocks(fsg, 12, + DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "WRITE(12)")) == 0) + reply = do_write(fsg); + 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: + fsg->data_size_from_cmnd = 0; + sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]); + if ((reply = check_command(fsg, fsg->cmnd_size, + DATA_DIR_UNKNOWN, ~0, 0, unknown)) == 0) { + fsg->curlun->sense_data = SS_INVALID_COMMAND; + reply = -EINVAL; + } + break; + } + up_read(&fsg->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 && fsg->data_dir == DATA_DIR_TO_HOST) { + reply = min((u32) reply, fsg->data_size_from_cmnd); + bh->inreq->length = reply; + bh->state = BUF_STATE_FULL; + fsg->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; + + /* 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 (mod_data.can_stall) { + fsg_set_halt(fsg, fsg->bulk_out); + halt_bulk_in_endpoint(fsg); + } + return -EINVAL; + } + + /* Save the command for later */ + fsg->cmnd_size = cbw->Length; + memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size); + if (cbw->Flags & US_BULK_FLAG_IN) + fsg->data_dir = DATA_DIR_TO_HOST; + else + fsg->data_dir = DATA_DIR_FROM_HOST; + fsg->data_size = le32_to_cpu(cbw->DataTransferLength); + if (fsg->data_size == 0) + fsg->data_dir = DATA_DIR_NONE; + fsg->lun = cbw->Lun; + fsg->tag = cbw->Tag; + return 0; +} + + +static int get_next_command(struct fsg_dev *fsg) +{ + struct fsg_buffhd *bh; + int rc = 0; + + if (transport_is_bbb()) { + + /* Wait for the next buffer to become available */ + bh = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + rc = sleep_thread(fsg); + if (rc) + return rc; + } + + /* Queue a request to read a Bulk-only CBW */ + set_bulk_out_req_length(fsg, bh, US_BULK_CB_WRAP_LEN); + start_transfer(fsg, fsg->bulk_out, bh->outreq, + &bh->outreq_busy, &bh->state); + + /* 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(fsg); + if (rc) + return rc; + } + smp_rmb(); + rc = received_cbw(fsg, bh); + bh->state = BUF_STATE_EMPTY; + + } else { // USB_PR_CB or USB_PR_CBI + + /* Wait for the next command to arrive */ + while (fsg->cbbuf_cmnd_size == 0) { + rc = sleep_thread(fsg); + if (rc) + return rc; + } + + /* Is the previous status interrupt request still busy? + * The host is allowed to skip reading the status, + * so we must cancel it. */ + if (fsg->intreq_busy) + usb_ep_dequeue(fsg->intr_in, fsg->intreq); + + /* Copy the command and mark the buffer empty */ + fsg->data_dir = DATA_DIR_UNKNOWN; + spin_lock_irq(&fsg->lock); + fsg->cmnd_size = fsg->cbbuf_cmnd_size; + memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size); + fsg->cbbuf_cmnd_size = 0; + spin_unlock_irq(&fsg->lock); + + /* Use LUN from the command */ + fsg->lun = fsg->cmnd[1] >> 5; + } + + /* Update current lun */ + if (fsg->lun >= 0 && fsg->lun < fsg->nluns) + fsg->curlun = &fsg->luns[fsg->lun]; + else + fsg->curlun = NULL; + + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep, + const struct usb_endpoint_descriptor *d) +{ + int rc; + + ep->driver_data = fsg; + ep->desc = d; + rc = usb_ep_enable(ep); + if (rc) + ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc); + return rc; +} + +static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep, + struct usb_request **preq) +{ + *preq = usb_ep_alloc_request(ep, GFP_ATOMIC); + if (*preq) + return 0; + ERROR(fsg, "can't allocate request for %s\n", ep->name); + return -ENOMEM; +} + +/* + * Reset interface setting and re-init endpoint state (toggle etc). + * Call with altsetting < 0 to disable the interface. The only other + * available altsetting is 0, which enables the interface. + */ +static int do_set_interface(struct fsg_dev *fsg, int altsetting) +{ + int rc = 0; + int i; + const struct usb_endpoint_descriptor *d; + + if (fsg->running) + DBG(fsg, "reset interface\n"); + +reset: + /* Deallocate the requests */ + for (i = 0; i < fsg_num_buffers; ++i) { + struct fsg_buffhd *bh = &fsg->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; + } + } + if (fsg->intreq) { + usb_ep_free_request(fsg->intr_in, fsg->intreq); + fsg->intreq = NULL; + } + + /* Disable the endpoints */ + if (fsg->bulk_in_enabled) { + usb_ep_disable(fsg->bulk_in); + fsg->bulk_in_enabled = 0; + } + if (fsg->bulk_out_enabled) { + usb_ep_disable(fsg->bulk_out); + fsg->bulk_out_enabled = 0; + } + if (fsg->intr_in_enabled) { + usb_ep_disable(fsg->intr_in); + fsg->intr_in_enabled = 0; + } + + fsg->running = 0; + if (altsetting < 0 || rc != 0) + return rc; + + DBG(fsg, "set interface %d\n", altsetting); + + /* Enable the endpoints */ + d = fsg_ep_desc(fsg->gadget, + &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc, + &fsg_ss_bulk_in_desc); + if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0) + goto reset; + fsg->bulk_in_enabled = 1; + + d = fsg_ep_desc(fsg->gadget, + &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc, + &fsg_ss_bulk_out_desc); + if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0) + goto reset; + fsg->bulk_out_enabled = 1; + fsg->bulk_out_maxpacket = usb_endpoint_maxp(d); + clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags); + + if (transport_is_cbi()) { + d = fsg_ep_desc(fsg->gadget, + &fsg_fs_intr_in_desc, &fsg_hs_intr_in_desc, + &fsg_ss_intr_in_desc); + if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0) + goto reset; + fsg->intr_in_enabled = 1; + } + + /* Allocate the requests */ + for (i = 0; i < fsg_num_buffers; ++i) { + struct fsg_buffhd *bh = &fsg->buffhds[i]; + + if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0) + goto reset; + if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0) + 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; + } + if (transport_is_cbi()) { + if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0) + goto reset; + fsg->intreq->complete = intr_in_complete; + } + + fsg->running = 1; + for (i = 0; i < fsg->nluns; ++i) + fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED; + return rc; +} + + +/* + * Change our operational configuration. This code must agree with the code + * that returns config descriptors, and with interface altsetting code. + * + * It's also responsible for power management interactions. Some + * configurations might not work with our current power sources. + * For now we just assume the gadget is always self-powered. + */ +static int do_set_config(struct fsg_dev *fsg, u8 new_config) +{ + int rc = 0; + + /* Disable the single interface */ + if (fsg->config != 0) { + DBG(fsg, "reset config\n"); + fsg->config = 0; + rc = do_set_interface(fsg, -1); + } + + /* Enable the interface */ + if (new_config != 0) { + fsg->config = new_config; + if ((rc = do_set_interface(fsg, 0)) != 0) + fsg->config = 0; // Reset on errors + else + INFO(fsg, "%s config #%d\n", + usb_speed_string(fsg->gadget->speed), + fsg->config); + } + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static void handle_exception(struct fsg_dev *fsg) +{ + siginfo_t info; + int sig; + int i; + int num_active; + struct fsg_buffhd *bh; + enum fsg_state old_state; + u8 new_config; + struct fsg_lun *curlun; + unsigned int exception_req_tag; + int rc; + + /* Clear the existing signals. Anything but SIGUSR1 is converted + * into a high-priority EXIT exception. */ + for (;;) { + sig = dequeue_signal_lock(current, ¤t->blocked, &info); + if (!sig) + break; + if (sig != SIGUSR1) { + if (fsg->state < FSG_STATE_EXIT) + DBG(fsg, "Main thread exiting on signal\n"); + raise_exception(fsg, FSG_STATE_EXIT); + } + } + + /* Cancel all the pending transfers */ + if (fsg->intreq_busy) + usb_ep_dequeue(fsg->intr_in, fsg->intreq); + for (i = 0; i < fsg_num_buffers; ++i) { + bh = &fsg->buffhds[i]; + if (bh->inreq_busy) + usb_ep_dequeue(fsg->bulk_in, bh->inreq); + if (bh->outreq_busy) + usb_ep_dequeue(fsg->bulk_out, bh->outreq); + } + + /* Wait until everything is idle */ + for (;;) { + num_active = fsg->intreq_busy; + for (i = 0; i < fsg_num_buffers; ++i) { + bh = &fsg->buffhds[i]; + num_active += bh->inreq_busy + bh->outreq_busy; + } + if (num_active == 0) + break; + if (sleep_thread(fsg)) + return; + } + + /* Clear out the controller's fifos */ + if (fsg->bulk_in_enabled) + usb_ep_fifo_flush(fsg->bulk_in); + if (fsg->bulk_out_enabled) + usb_ep_fifo_flush(fsg->bulk_out); + if (fsg->intr_in_enabled) + usb_ep_fifo_flush(fsg->intr_in); + + /* Reset the I/O buffer states and pointers, the SCSI + * state, and the exception. Then invoke the handler. */ + spin_lock_irq(&fsg->lock); + + for (i = 0; i < fsg_num_buffers; ++i) { + bh = &fsg->buffhds[i]; + bh->state = BUF_STATE_EMPTY; + } + fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain = + &fsg->buffhds[0]; + + exception_req_tag = fsg->exception_req_tag; + new_config = fsg->new_config; + old_state = fsg->state; + + if (old_state == FSG_STATE_ABORT_BULK_OUT) + fsg->state = FSG_STATE_STATUS_PHASE; + else { + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + curlun->prevent_medium_removal = 0; + curlun->sense_data = curlun->unit_attention_data = + SS_NO_SENSE; + curlun->sense_data_info = 0; + curlun->info_valid = 0; + } + fsg->state = FSG_STATE_IDLE; + } + spin_unlock_irq(&fsg->lock); + + /* Carry out any extra actions required for the exception */ + switch (old_state) { + default: + break; + + case FSG_STATE_ABORT_BULK_OUT: + send_status(fsg); + spin_lock_irq(&fsg->lock); + if (fsg->state == FSG_STATE_STATUS_PHASE) + fsg->state = FSG_STATE_IDLE; + spin_unlock_irq(&fsg->lock); + break; + + case FSG_STATE_RESET: + /* In case we were forced against our will to halt a + * bulk endpoint, clear the halt now. (The SuperH UDC + * requires this.) */ + if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags)) + usb_ep_clear_halt(fsg->bulk_in); + + if (transport_is_bbb()) { + if (fsg->ep0_req_tag == exception_req_tag) + ep0_queue(fsg); // Complete the status stage + + } else if (transport_is_cbi()) + send_status(fsg); // Status by interrupt pipe + + /* Technically this should go here, but it would only be + * a waste of time. Ditto for the INTERFACE_CHANGE and + * CONFIG_CHANGE cases. */ + // for (i = 0; i < fsg->nluns; ++i) + // fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED; + break; + + case FSG_STATE_INTERFACE_CHANGE: + rc = do_set_interface(fsg, 0); + if (fsg->ep0_req_tag != exception_req_tag) + break; + if (rc != 0) // STALL on errors + fsg_set_halt(fsg, fsg->ep0); + else // Complete the status stage + ep0_queue(fsg); + break; + + case FSG_STATE_CONFIG_CHANGE: + rc = do_set_config(fsg, new_config); + if (fsg->ep0_req_tag != exception_req_tag) + break; + if (rc != 0) // STALL on errors + fsg_set_halt(fsg, fsg->ep0); + else // Complete the status stage + ep0_queue(fsg); + break; + + case FSG_STATE_DISCONNECT: + for (i = 0; i < fsg->nluns; ++i) + fsg_lun_fsync_sub(fsg->luns + i); + do_set_config(fsg, 0); // Unconfigured state + break; + + case FSG_STATE_EXIT: + case FSG_STATE_TERMINATED: + do_set_config(fsg, 0); // Free resources + spin_lock_irq(&fsg->lock); + fsg->state = FSG_STATE_TERMINATED; // Stop the thread + spin_unlock_irq(&fsg->lock); + break; + } +} + + +/*-------------------------------------------------------------------------*/ + +static int fsg_main_thread(void *fsg_) +{ + struct fsg_dev *fsg = fsg_; + + /* 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 (fsg->state != FSG_STATE_TERMINATED) { + if (exception_in_progress(fsg) || signal_pending(current)) { + handle_exception(fsg); + continue; + } + + if (!fsg->running) { + sleep_thread(fsg); + continue; + } + + if (get_next_command(fsg)) + continue; + + spin_lock_irq(&fsg->lock); + if (!exception_in_progress(fsg)) + fsg->state = FSG_STATE_DATA_PHASE; + spin_unlock_irq(&fsg->lock); + + if (do_scsi_command(fsg) || finish_reply(fsg)) + continue; + + spin_lock_irq(&fsg->lock); + if (!exception_in_progress(fsg)) + fsg->state = FSG_STATE_STATUS_PHASE; + spin_unlock_irq(&fsg->lock); + + if (send_status(fsg)) + continue; + + spin_lock_irq(&fsg->lock); + if (!exception_in_progress(fsg)) + fsg->state = FSG_STATE_IDLE; + spin_unlock_irq(&fsg->lock); + } + + spin_lock_irq(&fsg->lock); + fsg->thread_task = NULL; + spin_unlock_irq(&fsg->lock); + + /* If we are exiting because of a signal, unregister the + * gadget driver. */ + if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) + usb_gadget_unregister_driver(&fsg_driver); + + /* Let the unbind and cleanup routines know the thread has exited */ + complete_and_exit(&fsg->thread_notifier, 0); +} + + +/*-------------------------------------------------------------------------*/ + + +/* The write permissions and store_xxx pointers are set in fsg_bind() */ +static DEVICE_ATTR(ro, 0444, fsg_show_ro, NULL); +static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, NULL); +static DEVICE_ATTR(file, 0444, fsg_show_file, NULL); + + +/*-------------------------------------------------------------------------*/ + +static void fsg_release(struct kref *ref) +{ + struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref); + + kfree(fsg->luns); + kfree(fsg); +} + +static void lun_release(struct device *dev) +{ + struct rw_semaphore *filesem = dev_get_drvdata(dev); + struct fsg_dev *fsg = + container_of(filesem, struct fsg_dev, filesem); + + kref_put(&fsg->ref, fsg_release); +} + +static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + int i; + struct fsg_lun *curlun; + struct usb_request *req = fsg->ep0req; + + DBG(fsg, "unbind\n"); + clear_bit(REGISTERED, &fsg->atomic_bitflags); + + /* If the thread isn't already dead, tell it to exit now */ + if (fsg->state != FSG_STATE_TERMINATED) { + raise_exception(fsg, FSG_STATE_EXIT); + wait_for_completion(&fsg->thread_notifier); + + /* The cleanup routine waits for this completion also */ + complete(&fsg->thread_notifier); + } + + /* Unregister the sysfs attribute files and the LUNs */ + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + if (curlun->registered) { + device_remove_file(&curlun->dev, &dev_attr_nofua); + device_remove_file(&curlun->dev, &dev_attr_ro); + device_remove_file(&curlun->dev, &dev_attr_file); + fsg_lun_close(curlun); + device_unregister(&curlun->dev); + curlun->registered = 0; + } + } + + /* Free the data buffers */ + for (i = 0; i < fsg_num_buffers; ++i) + kfree(fsg->buffhds[i].buf); + + /* Free the request and buffer for endpoint 0 */ + if (req) { + kfree(req->buf); + usb_ep_free_request(fsg->ep0, req); + } + + set_gadget_data(gadget, NULL); +} + + +static int __init check_parameters(struct fsg_dev *fsg) +{ + int prot; + int gcnum; + + /* Store the default values */ + mod_data.transport_type = USB_PR_BULK; + mod_data.transport_name = "Bulk-only"; + mod_data.protocol_type = USB_SC_SCSI; + mod_data.protocol_name = "Transparent SCSI"; + + /* Some peripheral controllers are known not to be able to + * halt bulk endpoints correctly. If one of them is present, + * disable stalls. + */ + if (gadget_is_at91(fsg->gadget)) + mod_data.can_stall = 0; + + if (mod_data.release == 0xffff) { // Parameter wasn't set + gcnum = usb_gadget_controller_number(fsg->gadget); + if (gcnum >= 0) + mod_data.release = 0x0300 + gcnum; + else { + WARNING(fsg, "controller '%s' not recognized\n", + fsg->gadget->name); + mod_data.release = 0x0399; + } + } + + prot = simple_strtol(mod_data.protocol_parm, NULL, 0); + +#ifdef CONFIG_USB_FILE_STORAGE_TEST + if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) { + ; // Use default setting + } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) { + mod_data.transport_type = USB_PR_CB; + mod_data.transport_name = "Control-Bulk"; + } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) { + mod_data.transport_type = USB_PR_CBI; + mod_data.transport_name = "Control-Bulk-Interrupt"; + } else { + ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm); + return -EINVAL; + } + + if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 || + prot == USB_SC_SCSI) { + ; // Use default setting + } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 || + prot == USB_SC_RBC) { + mod_data.protocol_type = USB_SC_RBC; + mod_data.protocol_name = "RBC"; + } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 || + strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 || + prot == USB_SC_8020) { + mod_data.protocol_type = USB_SC_8020; + mod_data.protocol_name = "8020i (ATAPI)"; + } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 || + prot == USB_SC_QIC) { + mod_data.protocol_type = USB_SC_QIC; + mod_data.protocol_name = "QIC-157"; + } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 || + prot == USB_SC_UFI) { + mod_data.protocol_type = USB_SC_UFI; + mod_data.protocol_name = "UFI"; + } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 || + prot == USB_SC_8070) { + mod_data.protocol_type = USB_SC_8070; + mod_data.protocol_name = "8070i"; + } else { + ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm); + return -EINVAL; + } + + mod_data.buflen &= PAGE_CACHE_MASK; + if (mod_data.buflen <= 0) { + ERROR(fsg, "invalid buflen\n"); + return -ETOOSMALL; + } + +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + /* Serial string handling. + * On a real device, the serial string would be loaded + * from permanent storage. */ + if (mod_data.serial) { + const char *ch; + unsigned len = 0; + + /* Sanity check : + * The CB[I] specification limits the serial string to + * 12 uppercase hexadecimal characters. + * BBB need at least 12 uppercase hexadecimal characters, + * with a maximum of 126. */ + for (ch = mod_data.serial; *ch; ++ch) { + ++len; + if ((*ch < '0' || *ch > '9') && + (*ch < 'A' || *ch > 'F')) { /* not uppercase hex */ + WARNING(fsg, + "Invalid serial string character: %c\n", + *ch); + goto no_serial; + } + } + if (len > 126 || + (mod_data.transport_type == USB_PR_BULK && len < 12) || + (mod_data.transport_type != USB_PR_BULK && len > 12)) { + WARNING(fsg, "Invalid serial string length!\n"); + goto no_serial; + } + fsg_strings[FSG_STRING_SERIAL - 1].s = mod_data.serial; + } else { + WARNING(fsg, "No serial-number string provided!\n"); + no_serial: + device_desc.iSerialNumber = 0; + } + + return 0; +} + + +static int __init fsg_bind(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = the_fsg; + int rc; + int i; + struct fsg_lun *curlun; + struct usb_ep *ep; + struct usb_request *req; + char *pathbuf, *p; + + fsg->gadget = gadget; + set_gadget_data(gadget, fsg); + fsg->ep0 = gadget->ep0; + fsg->ep0->driver_data = fsg; + + if ((rc = check_parameters(fsg)) != 0) + goto out; + + if (mod_data.removable) { // Enable the store_xxx attributes + dev_attr_file.attr.mode = 0644; + dev_attr_file.store = fsg_store_file; + if (!mod_data.cdrom) { + dev_attr_ro.attr.mode = 0644; + dev_attr_ro.store = fsg_store_ro; + } + } + + /* Only for removable media? */ + dev_attr_nofua.attr.mode = 0644; + dev_attr_nofua.store = fsg_store_nofua; + + /* Find out how many LUNs there should be */ + i = mod_data.nluns; + if (i == 0) + i = max(mod_data.num_filenames, 1u); + if (i > FSG_MAX_LUNS) { + ERROR(fsg, "invalid number of LUNs: %d\n", i); + rc = -EINVAL; + goto out; + } + + /* Create the LUNs, open their backing files, and register the + * LUN devices in sysfs. */ + fsg->luns = kzalloc(i * sizeof(struct fsg_lun), GFP_KERNEL); + if (!fsg->luns) { + rc = -ENOMEM; + goto out; + } + fsg->nluns = i; + + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + curlun->cdrom = !!mod_data.cdrom; + curlun->ro = mod_data.cdrom || mod_data.ro[i]; + curlun->initially_ro = curlun->ro; + curlun->removable = mod_data.removable; + curlun->nofua = mod_data.nofua[i]; + curlun->dev.release = lun_release; + curlun->dev.parent = &gadget->dev; + curlun->dev.driver = &fsg_driver.driver; + dev_set_drvdata(&curlun->dev, &fsg->filesem); + dev_set_name(&curlun->dev,"%s-lun%d", + dev_name(&gadget->dev), i); + + kref_get(&fsg->ref); + rc = device_register(&curlun->dev); + if (rc) { + INFO(fsg, "failed to register LUN%d: %d\n", i, rc); + put_device(&curlun->dev); + goto out; + } + curlun->registered = 1; + + rc = device_create_file(&curlun->dev, &dev_attr_ro); + if (rc) + goto out; + rc = device_create_file(&curlun->dev, &dev_attr_nofua); + if (rc) + goto out; + rc = device_create_file(&curlun->dev, &dev_attr_file); + if (rc) + goto out; + + if (mod_data.file[i] && *mod_data.file[i]) { + rc = fsg_lun_open(curlun, mod_data.file[i]); + if (rc) + goto out; + } else if (!mod_data.removable) { + ERROR(fsg, "no file given for LUN%d\n", i); + rc = -EINVAL; + goto out; + } + } + + /* Find all the endpoints we will use */ + usb_ep_autoconfig_reset(gadget); + ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc); + if (!ep) + goto autoconf_fail; + ep->driver_data = fsg; // 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; // claim the endpoint + fsg->bulk_out = ep; + + if (transport_is_cbi()) { + ep = usb_ep_autoconfig(gadget, &fsg_fs_intr_in_desc); + if (!ep) + goto autoconf_fail; + ep->driver_data = fsg; // claim the endpoint + fsg->intr_in = ep; + } + + /* Fix up the descriptors */ + device_desc.idVendor = cpu_to_le16(mod_data.vendor); + device_desc.idProduct = cpu_to_le16(mod_data.product); + device_desc.bcdDevice = cpu_to_le16(mod_data.release); + + i = (transport_is_cbi() ? 3 : 2); // Number of endpoints + fsg_intf_desc.bNumEndpoints = i; + fsg_intf_desc.bInterfaceSubClass = mod_data.protocol_type; + fsg_intf_desc.bInterfaceProtocol = mod_data.transport_type; + fsg_fs_function[i + FSG_FS_FUNCTION_PRE_EP_ENTRIES] = NULL; + + if (gadget_is_dualspeed(gadget)) { + fsg_hs_function[i + FSG_HS_FUNCTION_PRE_EP_ENTRIES] = NULL; + + /* 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; + fsg_hs_intr_in_desc.bEndpointAddress = + fsg_fs_intr_in_desc.bEndpointAddress; + } + + if (gadget_is_superspeed(gadget)) { + unsigned max_burst; + + fsg_ss_function[i + FSG_SS_FUNCTION_PRE_EP_ENTRIES] = NULL; + + /* Calculate bMaxBurst, we know packet size is 1024 */ + max_burst = min_t(unsigned, mod_data.buflen / 1024, 15); + + /* Assume endpoint addresses are the same for both speeds */ + 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; + } + + if (gadget_is_otg(gadget)) + fsg_otg_desc.bmAttributes |= USB_OTG_HNP; + + rc = -ENOMEM; + + /* Allocate the request and buffer for endpoint 0 */ + fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL); + if (!req) + goto out; + req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL); + if (!req->buf) + goto out; + req->complete = ep0_complete; + + /* Allocate the data buffers */ + for (i = 0; i < fsg_num_buffers; ++i) { + struct fsg_buffhd *bh = &fsg->buffhds[i]; + + /* Allocate for the bulk-in endpoint. We assume that + * the buffer will also work with the bulk-out (and + * interrupt-in) endpoint. */ + bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL); + if (!bh->buf) + goto out; + bh->next = bh + 1; + } + fsg->buffhds[fsg_num_buffers - 1].next = &fsg->buffhds[0]; + + /* This should reflect the actual gadget power source */ + usb_gadget_set_selfpowered(gadget); + + snprintf(fsg_string_manufacturer, sizeof fsg_string_manufacturer, + "%s %s with %s", + init_utsname()->sysname, init_utsname()->release, + gadget->name); + + fsg->thread_task = kthread_create(fsg_main_thread, fsg, + "file-storage-gadget"); + if (IS_ERR(fsg->thread_task)) { + rc = PTR_ERR(fsg->thread_task); + goto out; + } + + INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n"); + INFO(fsg, "NOTE: This driver is deprecated. " + "Consider using g_mass_storage instead.\n"); + INFO(fsg, "Number of LUNs=%d\n", fsg->nluns); + + pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + if (fsg_lun_is_open(curlun)) { + p = NULL; + if (pathbuf) { + p = d_path(&curlun->filp->f_path, + pathbuf, PATH_MAX); + if (IS_ERR(p)) + p = NULL; + } + LINFO(curlun, "ro=%d, nofua=%d, file: %s\n", + curlun->ro, curlun->nofua, (p ? p : "(error)")); + } + } + kfree(pathbuf); + + DBG(fsg, "transport=%s (x%02x)\n", + mod_data.transport_name, mod_data.transport_type); + DBG(fsg, "protocol=%s (x%02x)\n", + mod_data.protocol_name, mod_data.protocol_type); + DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n", + mod_data.vendor, mod_data.product, mod_data.release); + DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n", + mod_data.removable, mod_data.can_stall, + mod_data.cdrom, mod_data.buflen); + DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task)); + + set_bit(REGISTERED, &fsg->atomic_bitflags); + + /* Tell the thread to start working */ + wake_up_process(fsg->thread_task); + return 0; + +autoconf_fail: + ERROR(fsg, "unable to autoconfigure all endpoints\n"); + rc = -ENOTSUPP; + +out: + fsg->state = FSG_STATE_TERMINATED; // The thread is dead + fsg_unbind(gadget); + complete(&fsg->thread_notifier); + return rc; +} + + +/*-------------------------------------------------------------------------*/ + +static void fsg_suspend(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + + DBG(fsg, "suspend\n"); + set_bit(SUSPENDED, &fsg->atomic_bitflags); +} + +static void fsg_resume(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + + DBG(fsg, "resume\n"); + clear_bit(SUSPENDED, &fsg->atomic_bitflags); +} + + +/*-------------------------------------------------------------------------*/ + +static struct usb_gadget_driver fsg_driver = { + .max_speed = USB_SPEED_SUPER, + .function = (char *) fsg_string_product, + .unbind = fsg_unbind, + .disconnect = fsg_disconnect, + .setup = fsg_setup, + .suspend = fsg_suspend, + .resume = fsg_resume, + + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + // .release = ... + // .suspend = ... + // .resume = ... + }, +}; + + +static int __init fsg_alloc(void) +{ + struct fsg_dev *fsg; + + fsg = kzalloc(sizeof *fsg + + fsg_num_buffers * sizeof *(fsg->buffhds), GFP_KERNEL); + + if (!fsg) + return -ENOMEM; + spin_lock_init(&fsg->lock); + init_rwsem(&fsg->filesem); + kref_init(&fsg->ref); + init_completion(&fsg->thread_notifier); + + the_fsg = fsg; + return 0; +} + + +static int __init fsg_init(void) +{ + int rc; + struct fsg_dev *fsg; + + rc = fsg_num_buffers_validate(); + if (rc != 0) + return rc; + + if ((rc = fsg_alloc()) != 0) + return rc; + fsg = the_fsg; + if ((rc = usb_gadget_probe_driver(&fsg_driver, fsg_bind)) != 0) + kref_put(&fsg->ref, fsg_release); + return rc; +} +module_init(fsg_init); + + +static void __exit fsg_cleanup(void) +{ + struct fsg_dev *fsg = the_fsg; + + /* Unregister the driver iff the thread hasn't already done so */ + if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) + usb_gadget_unregister_driver(&fsg_driver); + + /* Wait for the thread to finish up */ + wait_for_completion(&fsg->thread_notifier); + + kref_put(&fsg->ref, fsg_release); +} +module_exit(fsg_cleanup); |