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Diffstat (limited to 'drivers/usb/gadget/file_storage.c')
-rw-r--r-- | drivers/usb/gadget/file_storage.c | 4139 |
1 files changed, 4139 insertions, 0 deletions
diff --git a/drivers/usb/gadget/file_storage.c b/drivers/usb/gadget/file_storage.c new file mode 100644 index 00000000000..4857f0e4ef4 --- /dev/null +++ b/drivers/usb/gadget/file_storage.c @@ -0,0 +1,4139 @@ +/* + * file_storage.c -- File-backed USB Storage Gadget, for USB development + * + * Copyright (C) 2003-2005 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. 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. 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, and release 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. + * + * 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. + * + * Module options: + * + * file=filename[,filename...] + * Required if "removable" is not set, names of + * the files or block devices used for + * backing storage + * 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 + * 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) + * stall Default determined according to the type of + * USB device controller (usually true), + * boolean to permit the driver to halt + * bulk endpoints + * + * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro", + * "removable", and "luns" 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" 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. + * + * This gadget driver is heavily based on "Gadget Zero" by David Brownell. + */ + + +/* + * 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. + */ + + +#undef DEBUG +#undef VERBOSE +#undef DUMP_MSGS + +#include <linux/config.h> + +#include <asm/system.h> +#include <asm/uaccess.h> + +#include <linux/bitops.h> +#include <linux/blkdev.h> +#include <linux/compiler.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/init.h> +#include <linux/kernel.h> +#include <linux/limits.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/pagemap.h> +#include <linux/rwsem.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/string.h> +#include <linux/suspend.h> +#include <linux/utsname.h> +#include <linux/wait.h> + +#include <linux/usb_ch9.h> +#include <linux/usb_gadget.h> + +#include "gadget_chips.h" + + +/*-------------------------------------------------------------------------*/ + +#define DRIVER_DESC "File-backed Storage Gadget" +#define DRIVER_NAME "g_file_storage" +#define DRIVER_VERSION "20 October 2004" + +static const char longname[] = DRIVER_DESC; +static const char shortname[] = DRIVER_NAME; + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_AUTHOR("Alan Stern"); +MODULE_LICENSE("Dual BSD/GPL"); + +/* Thanks to NetChip Technologies for donating this product ID. + * + * DO NOT REUSE THESE IDs with any other driver!! Ever!! + * Instead: allocate your own, using normal USB-IF procedures. */ +#define DRIVER_VENDOR_ID 0x0525 // NetChip +#define DRIVER_PRODUCT_ID 0xa4a5 // Linux-USB File-backed Storage Gadget + + +/* + * 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. + */ + + +/*-------------------------------------------------------------------------*/ + +#define xprintk(f,level,fmt,args...) \ + dev_printk(level , &(f)->gadget->dev , fmt , ## args) +#define yprintk(l,level,fmt,args...) \ + dev_printk(level , &(l)->dev , fmt , ## args) + +#ifdef DEBUG +#define DBG(fsg,fmt,args...) \ + xprintk(fsg , KERN_DEBUG , fmt , ## args) +#define LDBG(lun,fmt,args...) \ + yprintk(lun , KERN_DEBUG , fmt , ## args) +#define MDBG(fmt,args...) \ + printk(KERN_DEBUG DRIVER_NAME ": " fmt , ## args) +#else +#define DBG(fsg,fmt,args...) \ + do { } while (0) +#define LDBG(lun,fmt,args...) \ + do { } while (0) +#define MDBG(fmt,args...) \ + do { } while (0) +#undef VERBOSE +#undef DUMP_MSGS +#endif /* DEBUG */ + +#ifdef VERBOSE +#define VDBG DBG +#define VLDBG LDBG +#else +#define VDBG(fsg,fmt,args...) \ + do { } while (0) +#define VLDBG(lun,fmt,args...) \ + do { } while (0) +#endif /* VERBOSE */ + +#define ERROR(fsg,fmt,args...) \ + xprintk(fsg , KERN_ERR , fmt , ## args) +#define LERROR(lun,fmt,args...) \ + yprintk(lun , KERN_ERR , fmt , ## args) + +#define WARN(fsg,fmt,args...) \ + xprintk(fsg , KERN_WARNING , fmt , ## args) +#define LWARN(lun,fmt,args...) \ + yprintk(lun , KERN_WARNING , fmt , ## args) + +#define INFO(fsg,fmt,args...) \ + xprintk(fsg , KERN_INFO , fmt , ## args) +#define LINFO(lun,fmt,args...) \ + yprintk(lun , KERN_INFO , fmt , ## args) + +#define MINFO(fmt,args...) \ + printk(KERN_INFO DRIVER_NAME ": " fmt , ## args) + + +/*-------------------------------------------------------------------------*/ + +/* Encapsulate the module parameter settings */ + +#define MAX_LUNS 8 + + /* Arggh! There should be a module_param_array_named macro! */ +static char *file[MAX_LUNS] = {NULL, }; +static int ro[MAX_LUNS] = {0, }; + +static struct { + int num_filenames; + int num_ros; + unsigned int nluns; + + char *transport_parm; + char *protocol_parm; + int removable; + unsigned short vendor; + unsigned short product; + unsigned short release; + unsigned int buflen; + int can_stall; + + int transport_type; + char *transport_name; + int protocol_type; + char *protocol_name; + +} mod_data = { // Default values + .transport_parm = "BBB", + .protocol_parm = "SCSI", + .removable = 0, + .vendor = DRIVER_VENDOR_ID, + .product = DRIVER_PRODUCT_ID, + .release = 0xffff, // Use controller chip type + .buflen = 16384, + .can_stall = 1, + }; + + +module_param_array(file, charp, &mod_data.num_filenames, S_IRUGO); +MODULE_PARM_DESC(file, "names of backing files or devices"); + +module_param_array(ro, bool, &mod_data.num_ros, S_IRUGO); +MODULE_PARM_DESC(ro, "true to force read-only"); + +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"); + + +/* 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"); + +module_param_named(stall, mod_data.can_stall, bool, S_IRUGO); +MODULE_PARM_DESC(stall, "false to prevent bulk stalls"); + +#endif /* CONFIG_USB_FILE_STORAGE_TEST */ + + +/*-------------------------------------------------------------------------*/ + +/* USB protocol value = the transport method */ +#define USB_PR_CBI 0x00 // Control/Bulk/Interrupt +#define USB_PR_CB 0x01 // Control/Bulk w/o interrupt +#define USB_PR_BULK 0x50 // Bulk-only + +/* USB subclass value = the protocol encapsulation */ +#define USB_SC_RBC 0x01 // Reduced Block Commands (flash) +#define USB_SC_8020 0x02 // SFF-8020i, MMC-2, ATAPI (CD-ROM) +#define USB_SC_QIC 0x03 // QIC-157 (tape) +#define USB_SC_UFI 0x04 // UFI (floppy) +#define USB_SC_8070 0x05 // SFF-8070i (removable) +#define USB_SC_SCSI 0x06 // Transparent SCSI + +/* Bulk-only data structures */ + +/* Command Block Wrapper */ +struct bulk_cb_wrap { + __le32 Signature; // Contains 'USBC' + u32 Tag; // Unique per command id + __le32 DataTransferLength; // Size of the data + u8 Flags; // Direction in bit 7 + u8 Lun; // LUN (normally 0) + u8 Length; // Of the CDB, <= MAX_COMMAND_SIZE + u8 CDB[16]; // Command Data Block +}; + +#define USB_BULK_CB_WRAP_LEN 31 +#define USB_BULK_CB_SIG 0x43425355 // Spells out USBC +#define USB_BULK_IN_FLAG 0x80 + +/* Command Status Wrapper */ +struct bulk_cs_wrap { + __le32 Signature; // Should = 'USBS' + u32 Tag; // Same as original command + __le32 Residue; // Amount not transferred + u8 Status; // See below +}; + +#define USB_BULK_CS_WRAP_LEN 13 +#define USB_BULK_CS_SIG 0x53425355 // Spells out 'USBS' +#define USB_STATUS_PASS 0 +#define USB_STATUS_FAIL 1 +#define USB_STATUS_PHASE_ERROR 2 + +/* Bulk-only class specific requests */ +#define USB_BULK_RESET_REQUEST 0xff +#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe + + +/* CBI Interrupt data structure */ +struct interrupt_data { + u8 bType; + u8 bValue; +}; + +#define CBI_INTERRUPT_DATA_LEN 2 + +/* CBI Accept Device-Specific Command request */ +#define USB_CBI_ADSC_REQUEST 0x00 + + +#define MAX_COMMAND_SIZE 16 // Length of a SCSI Command Data Block + +/* SCSI commands that we recognize */ +#define SC_FORMAT_UNIT 0x04 +#define SC_INQUIRY 0x12 +#define SC_MODE_SELECT_6 0x15 +#define SC_MODE_SELECT_10 0x55 +#define SC_MODE_SENSE_6 0x1a +#define SC_MODE_SENSE_10 0x5a +#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e +#define SC_READ_6 0x08 +#define SC_READ_10 0x28 +#define SC_READ_12 0xa8 +#define SC_READ_CAPACITY 0x25 +#define SC_READ_FORMAT_CAPACITIES 0x23 +#define SC_RELEASE 0x17 +#define SC_REQUEST_SENSE 0x03 +#define SC_RESERVE 0x16 +#define SC_SEND_DIAGNOSTIC 0x1d +#define SC_START_STOP_UNIT 0x1b +#define SC_SYNCHRONIZE_CACHE 0x35 +#define SC_TEST_UNIT_READY 0x00 +#define SC_VERIFY 0x2f +#define SC_WRITE_6 0x0a +#define SC_WRITE_10 0x2a +#define SC_WRITE_12 0xaa + +/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */ +#define SS_NO_SENSE 0 +#define SS_COMMUNICATION_FAILURE 0x040800 +#define SS_INVALID_COMMAND 0x052000 +#define SS_INVALID_FIELD_IN_CDB 0x052400 +#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100 +#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500 +#define SS_MEDIUM_NOT_PRESENT 0x023a00 +#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302 +#define SS_NOT_READY_TO_READY_TRANSITION 0x062800 +#define SS_RESET_OCCURRED 0x062900 +#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900 +#define SS_UNRECOVERED_READ_ERROR 0x031100 +#define SS_WRITE_ERROR 0x030c02 +#define SS_WRITE_PROTECTED 0x072700 + +#define SK(x) ((u8) ((x) >> 16)) // Sense Key byte, etc. +#define ASC(x) ((u8) ((x) >> 8)) +#define ASCQ(x) ((u8) (x)) + + +/*-------------------------------------------------------------------------*/ + +/* + * 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 lun { + struct file *filp; + loff_t file_length; + loff_t num_sectors; + + unsigned int ro : 1; + unsigned int prevent_medium_removal : 1; + unsigned int registered : 1; + + u32 sense_data; + u32 sense_data_info; + u32 unit_attention_data; + + struct device dev; +}; + +#define backing_file_is_open(curlun) ((curlun)->filp != NULL) + +static inline struct lun *dev_to_lun(struct device *dev) +{ + return container_of(dev, struct lun, dev); +} + + +/* Big enough to hold our biggest descriptor */ +#define EP0_BUFSIZE 256 +#define DELAYED_STATUS (EP0_BUFSIZE + 999) // An impossibly large value + +/* Number of buffers we will use. 2 is enough for double-buffering */ +#define NUM_BUFFERS 2 + +enum fsg_buffer_state { + BUF_STATE_EMPTY = 0, + BUF_STATE_FULL, + BUF_STATE_BUSY +}; + +struct fsg_buffhd { + void *buf; + dma_addr_t dma; + volatile enum fsg_buffer_state state; + struct fsg_buffhd *next; + + /* The NetChip 2280 is faster, and handles some protocol faults + * better, if we don't submit any short bulk-out read requests. + * So we will record the intended request length here. */ + unsigned int bulk_out_intended_length; + + struct usb_request *inreq; + volatile int inreq_busy; + struct usb_request *outreq; + volatile int outreq_busy; +}; + +enum fsg_state { + FSG_STATE_COMMAND_PHASE = -10, // This one isn't used anywhere + FSG_STATE_DATA_PHASE, + FSG_STATE_STATUS_PHASE, + + FSG_STATE_IDLE = 0, + FSG_STATE_ABORT_BULK_OUT, + FSG_STATE_RESET, + FSG_STATE_INTERFACE_CHANGE, + FSG_STATE_CONFIG_CHANGE, + FSG_STATE_DISCONNECT, + FSG_STATE_EXIT, + FSG_STATE_TERMINATED +}; + +enum data_direction { + DATA_DIR_UNKNOWN = 0, + DATA_DIR_FROM_HOST, + DATA_DIR_TO_HOST, + DATA_DIR_NONE +}; + +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; + + struct usb_ep *ep0; // Handy copy of gadget->ep0 + struct usb_request *ep0req; // For control responses + volatile unsigned int ep0_req_tag; + const char *ep0req_name; + + struct usb_request *intreq; // For interrupt responses + volatile 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 CLEAR_BULK_HALTS 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; + struct fsg_buffhd buffhds[NUM_BUFFERS]; + + wait_queue_head_t thread_wqh; + int thread_wakeup_needed; + struct completion thread_notifier; + int thread_pid; + struct task_struct *thread_task; + sigset_t thread_signal_mask; + + 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 lun *luns; + struct lun *curlun; + struct completion lun_released; +}; + +typedef void (*fsg_routine_t)(struct fsg_dev *); + +static int inline 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 inline 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 void close_backing_file(struct lun *curlun); +static void close_all_backing_files(struct fsg_dev *fsg); + + +/*-------------------------------------------------------------------------*/ + +#ifdef DUMP_MSGS + +static void dump_msg(struct fsg_dev *fsg, const char *label, + const u8 *buf, unsigned int length) +{ + unsigned int start, num, i; + char line[52], *p; + + if (length >= 512) + return; + DBG(fsg, "%s, length %u:\n", label, length); + + start = 0; + while (length > 0) { + num = min(length, 16u); + p = line; + for (i = 0; i < num; ++i) { + if (i == 8) + *p++ = ' '; + sprintf(p, " %02x", buf[i]); + p += 3; + } + *p = 0; + printk(KERN_DEBUG "%6x: %s\n", start, line); + buf += num; + start += num; + length -= num; + } +} + +static void inline dump_cdb(struct fsg_dev *fsg) +{} + +#else + +static void inline dump_msg(struct fsg_dev *fsg, const char *label, + const u8 *buf, unsigned int length) +{} + +static void inline dump_cdb(struct fsg_dev *fsg) +{ + int i; + char cmdbuf[3*MAX_COMMAND_SIZE + 1]; + + for (i = 0; i < fsg->cmnd_size; ++i) + sprintf(cmdbuf + i*3, " %02x", fsg->cmnd[i]); + VDBG(fsg, "SCSI CDB: %s\n", cmdbuf); +} + +#endif /* DUMP_MSGS */ + + +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); +} + + +/*-------------------------------------------------------------------------*/ + +/* Routines for unaligned data access */ + +static u16 inline get_be16(u8 *buf) +{ + return ((u16) buf[0] << 8) | ((u16) buf[1]); +} + +static u32 inline get_be32(u8 *buf) +{ + return ((u32) buf[0] << 24) | ((u32) buf[1] << 16) | + ((u32) buf[2] << 8) | ((u32) buf[3]); +} + +static void inline put_be16(u8 *buf, u16 val) +{ + buf[0] = val >> 8; + buf[1] = val; +} + +static void inline put_be32(u8 *buf, u32 val) +{ + buf[0] = val >> 24; + buf[1] = val >> 16; + buf[2] = val >> 8; + buf[3] = val; +} + + +/*-------------------------------------------------------------------------*/ + +/* + * 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(). + */ +#define STRING_MANUFACTURER 1 +#define STRING_PRODUCT 2 +#define STRING_SERIAL 3 +#define STRING_CONFIG 4 +#define STRING_INTERFACE 5 + +/* 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 = __constant_cpu_to_le16(0x0200), + .bDeviceClass = USB_CLASS_PER_INTERFACE, + + /* The next three values can be overridden by module parameters */ + .idVendor = __constant_cpu_to_le16(DRIVER_VENDOR_ID), + .idProduct = __constant_cpu_to_le16(DRIVER_PRODUCT_ID), + .bcdDevice = __constant_cpu_to_le16(0xffff), + + .iManufacturer = STRING_MANUFACTURER, + .iProduct = STRING_PRODUCT, + .iSerialNumber = 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 = STRING_CONFIG, + .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER, + .bMaxPower = 1, // self-powered +}; + +static struct usb_otg_descriptor +otg_desc = { + .bLength = sizeof(otg_desc), + .bDescriptorType = USB_DT_OTG, + + .bmAttributes = USB_OTG_SRP, +}; + +/* There is only one interface. */ + +static struct usb_interface_descriptor +intf_desc = { + .bLength = sizeof intf_desc, + .bDescriptorType = USB_DT_INTERFACE, + + .bNumEndpoints = 2, // Adjusted during fsg_bind() + .bInterfaceClass = USB_CLASS_MASS_STORAGE, + .bInterfaceSubClass = USB_SC_SCSI, // Adjusted during fsg_bind() + .bInterfaceProtocol = USB_PR_BULK, // Adjusted during fsg_bind() + .iInterface = STRING_INTERFACE, +}; + +/* Three full-speed endpoint descriptors: bulk-in, bulk-out, + * and interrupt-in. */ + +static struct usb_endpoint_descriptor +fs_bulk_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + /* wMaxPacketSize set by autoconfiguration */ +}; + +static struct usb_endpoint_descriptor +fs_bulk_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + /* wMaxPacketSize set by autoconfiguration */ +}; + +static struct usb_endpoint_descriptor +fs_intr_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_INT, + .wMaxPacketSize = __constant_cpu_to_le16(2), + .bInterval = 32, // frames -> 32 ms +}; + +static const struct usb_descriptor_header *fs_function[] = { + (struct usb_descriptor_header *) &otg_desc, + (struct usb_descriptor_header *) &intf_desc, + (struct usb_descriptor_header *) &fs_bulk_in_desc, + (struct usb_descriptor_header *) &fs_bulk_out_desc, + (struct usb_descriptor_header *) &fs_intr_in_desc, + NULL, +}; +#define FS_FUNCTION_PRE_EP_ENTRIES 2 + + +#ifdef CONFIG_USB_GADGET_DUALSPEED + +/* + * USB 2.0 devices need to expose both high speed and full speed + * descriptors, unless they only run at full speed. + * + * That means alternate endpoint descriptors (bigger packets) + * and a "device qualifier" ... plus more construction options + * for the config descriptor. + */ +static struct usb_qualifier_descriptor +dev_qualifier = { + .bLength = sizeof dev_qualifier, + .bDescriptorType = USB_DT_DEVICE_QUALIFIER, + + .bcdUSB = __constant_cpu_to_le16(0x0200), + .bDeviceClass = USB_CLASS_PER_INTERFACE, + + .bNumConfigurations = 1, +}; + +static struct usb_endpoint_descriptor +hs_bulk_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */ + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = __constant_cpu_to_le16(512), +}; + +static struct usb_endpoint_descriptor +hs_bulk_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */ + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = __constant_cpu_to_le16(512), + .bInterval = 1, // NAK every 1 uframe +}; + +static struct usb_endpoint_descriptor +hs_intr_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */ + .bmAttributes = USB_ENDPOINT_XFER_INT, + .wMaxPacketSize = __constant_cpu_to_le16(2), + .bInterval = 9, // 2**(9-1) = 256 uframes -> 32 ms +}; + +static const struct usb_descriptor_header *hs_function[] = { + (struct usb_descriptor_header *) &otg_desc, + (struct usb_descriptor_header *) &intf_desc, + (struct usb_descriptor_header *) &hs_bulk_in_desc, + (struct usb_descriptor_header *) &hs_bulk_out_desc, + (struct usb_descriptor_header *) &hs_intr_in_desc, + NULL, +}; +#define HS_FUNCTION_PRE_EP_ENTRIES 2 + +/* Maxpacket and other transfer characteristics vary by speed. */ +#define ep_desc(g,fs,hs) (((g)->speed==USB_SPEED_HIGH) ? (hs) : (fs)) + +#else + +/* If there's no high speed support, always use the full-speed descriptor. */ +#define ep_desc(g,fs,hs) fs + +#endif /* !CONFIG_USB_GADGET_DUALSPEED */ + + +/* The CBI specification limits the serial string to 12 uppercase hexadecimal + * characters. */ +static char manufacturer[64]; +static char serial[13]; + +/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */ +static struct usb_string strings[] = { + {STRING_MANUFACTURER, manufacturer}, + {STRING_PRODUCT, longname}, + {STRING_SERIAL, serial}, + {STRING_CONFIG, "Self-powered"}, + {STRING_INTERFACE, "Mass Storage"}, + {} +}; + +static struct usb_gadget_strings stringtab = { + .language = 0x0409, // en-us + .strings = strings, +}; + + +/* + * 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) +{ +#ifdef CONFIG_USB_GADGET_DUALSPEED + enum usb_device_speed speed = gadget->speed; +#endif + int len; + const struct usb_descriptor_header **function; + + if (index > 0) + return -EINVAL; + +#ifdef CONFIG_USB_GADGET_DUALSPEED + if (type == USB_DT_OTHER_SPEED_CONFIG) + speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed; + if (speed == USB_SPEED_HIGH) + function = hs_function; + else +#endif + function = fs_function; + + /* for now, don't advertise srp-only devices */ + if (!gadget->is_otg) + 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 */ + +static void wakeup_thread(struct fsg_dev *fsg) +{ + /* Tell the main thread that something has happened */ + fsg->thread_wakeup_needed = 1; + wake_up_all(&fsg->thread_wqh); +} + + +static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state) +{ + unsigned long flags; + struct task_struct *thread_task; + + /* 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; + thread_task = fsg->thread_task; + if (thread_task) + send_sig_info(SIGUSR1, SEND_SIG_FORCED, 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 */ + WARN(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 = (struct fsg_dev *) 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", __FUNCTION__, + 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 = (struct fsg_dev *) ep->driver_data; + struct fsg_buffhd *bh = (struct fsg_buffhd *) req->context; + + if (req->status || req->actual != req->length) + DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__, + 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 */ + spin_lock(&fsg->lock); + bh->inreq_busy = 0; + bh->state = BUF_STATE_EMPTY; + spin_unlock(&fsg->lock); + wakeup_thread(fsg); +} + +static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = (struct fsg_dev *) ep->driver_data; + struct fsg_buffhd *bh = (struct fsg_buffhd *) 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", __FUNCTION__, + 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 */ + spin_lock(&fsg->lock); + bh->outreq_busy = 0; + bh->state = BUF_STATE_FULL; + spin_unlock(&fsg->lock); + wakeup_thread(fsg); +} + + +#ifdef CONFIG_USB_FILE_STORAGE_TEST +static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct fsg_dev *fsg = (struct fsg_dev *) ep->driver_data; + struct fsg_buffhd *bh = (struct fsg_buffhd *) req->context; + + if (req->status || req->actual != req->length) + DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__, + 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 */ + spin_lock(&fsg->lock); + fsg->intreq_busy = 0; + bh->state = BUF_STATE_EMPTY; + spin_unlock(&fsg->lock); + wakeup_thread(fsg); +} + +#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] = { + SC_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) + WARN(fsg, "CB[I] overwriting previous command\n"); + fsg->cbbuf_cmnd_size = req->actual; + memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size); + + spin_unlock(&fsg->lock); + wakeup_thread(fsg); +} + +#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 = ctrl->wIndex; + u16 w_length = ctrl->wLength; + + if (!fsg->config) + return value; + + /* Handle Bulk-only class-specific requests */ + if (transport_is_bbb()) { + switch (ctrl->bRequest) { + + case USB_BULK_RESET_REQUEST: + if (ctrl->bRequestType != (USB_DIR_OUT | + USB_TYPE_CLASS | USB_RECIP_INTERFACE)) + break; + if (w_index != 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 USB_BULK_GET_MAX_LUN_REQUEST: + if (ctrl->bRequestType != (USB_DIR_IN | + USB_TYPE_CLASS | USB_RECIP_INTERFACE)) + break; + if (w_index != 0) { + value = -EDOM; + break; + } + VDBG(fsg, "get max LUN\n"); + *(u8 *) req->buf = fsg->nluns - 1; + value = min(w_length, (u16) 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) { + 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, + 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 = ctrl->wIndex; + u16 w_value = ctrl->wValue; + u16 w_length = ctrl->wLength; + + /* 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"); + value = min(w_length, (u16) sizeof device_desc); + memcpy(req->buf, &device_desc, value); + break; +#ifdef CONFIG_USB_GADGET_DUALSPEED + case USB_DT_DEVICE_QUALIFIER: + VDBG(fsg, "get device qualifier\n"); + if (!fsg->gadget->is_dualspeed) + break; + value = min(w_length, (u16) 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 (!fsg->gadget->is_dualspeed) + break; + goto get_config; +#endif + case USB_DT_CONFIG: + VDBG(fsg, "get configuration descriptor\n"); +#ifdef CONFIG_USB_GADGET_DUALSPEED + get_config: +#endif + value = populate_config_buf(fsg->gadget, + req->buf, + w_value >> 8, + w_value & 0xff); + if (value >= 0) + value = min(w_length, (u16) value); + break; + + case USB_DT_STRING: + VDBG(fsg, "get string descriptor\n"); + + /* wIndex == language code */ + value = usb_gadget_get_string(&stringtab, + w_value & 0xff, req->buf); + if (value >= 0) + value = min(w_length, (u16) value); + 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 = min(w_length, (u16) 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 = min(w_length, (u16) 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, w_length); + } + + 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; + + ++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) { + fsg->ep0req->length = rc; + fsg->ep0req->zero = (rc < ctrl->wLength && + (rc % gadget->ep0->maxpacket) == 0); + 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, volatile int *pbusy, + volatile 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); + *pbusy = 1; + *state = BUF_STATE_BUSY; + 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)) + WARN(fsg, "error in submission: %s --> %d\n", + ep->name, rc); + } +} + + +static int sleep_thread(struct fsg_dev *fsg) +{ + int rc; + + /* Wait until a signal arrives or we are woken up */ + rc = wait_event_interruptible(fsg->thread_wqh, + fsg->thread_wakeup_needed); + fsg->thread_wakeup_needed = 0; + if (current->flags & PF_FREEZE) + refrigerator(PF_FREEZE); + return (rc ? -EINTR : 0); +} + + +/*-------------------------------------------------------------------------*/ + +static int do_read(struct fsg_dev *fsg) +{ + struct 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; + unsigned int partial_page; + ssize_t nread; + + /* Get the starting Logical Block Address and check that it's + * not too big */ + if (fsg->cmnd[0] == SC_READ_6) + lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]); + else { + lba = get_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) << 9; + + /* 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. + * Finally, if we're not at a page boundary, don't read past + * the next page. + * If this means reading 0 then we were asked to read past + * the end of file. */ + amount = min((unsigned int) amount_left, mod_data.buflen); + amount = min((loff_t) amount, + curlun->file_length - file_offset); + partial_page = file_offset & (PAGE_CACHE_SIZE - 1); + if (partial_page > 0) + amount = min(amount, (unsigned int) PAGE_CACHE_SIZE - + partial_page); + + /* Wait for the next buffer to become available */ + bh = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + if ((rc = sleep_thread(fsg)) != 0) + 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 >> 9; + 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 -= (nread & 511); // Round down to a block + } + file_offset += nread; + amount_left -= nread; + fsg->residue -= nread; + 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 >> 9; + 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 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; + unsigned int partial_page; + ssize_t nwritten; + int rc; + + if (curlun->ro) { + curlun->sense_data = SS_WRITE_PROTECTED; + return -EINVAL; + } + curlun->filp->f_flags &= ~O_SYNC; // Default is not to wait + + /* Get the starting Logical Block Address and check that it's + * not too big */ + if (fsg->cmnd[0] == SC_WRITE_6) + lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]); + else { + lba = get_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; + } + if (fsg->cmnd[1] & 0x08) // FUA + curlun->filp->f_flags |= O_SYNC; + } + 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) << 9; + 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 don't get more than the buffer size. + * And don't try to go past the end of the file. + * If we're not at a page boundary, + * don't go past the next page. + * If this means getting 0, then we were asked + * to write past the end of file. + * Finally, round down to a block boundary. */ + amount = min(amount_left_to_req, mod_data.buflen); + amount = min((loff_t) amount, curlun->file_length - + usb_offset); + partial_page = usb_offset & (PAGE_CACHE_SIZE - 1); + if (partial_page > 0) + amount = min(amount, + (unsigned int) PAGE_CACHE_SIZE - partial_page); + + if (amount == 0) { + get_some_more = 0; + curlun->sense_data = + SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; + curlun->sense_data_info = usb_offset >> 9; + continue; + } + amount -= (amount & 511); + if (amount == 0) { + + /* Why were we were asked to transfer a + * partial block? */ + get_some_more = 0; + 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; + + /* amount is always divisible by 512, hence by + * the bulk-out maxpacket size */ + bh->outreq->length = bh->bulk_out_intended_length = + 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) { + 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 >> 9; + 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; + } + + /* 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 -= (nwritten & 511); + // Round down to a block + } + 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 >> 9; + break; + } + + /* Did the host decide to stop early? */ + if (bh->outreq->actual != bh->outreq->length) { + fsg->short_packet_received = 1; + break; + } + continue; + } + + /* Wait for something to happen */ + if ((rc = sleep_thread(fsg)) != 0) + return rc; + } + + return -EIO; // No default reply +} + + +/*-------------------------------------------------------------------------*/ + +/* Sync the file data, don't bother with the metadata. + * This code was copied from fs/buffer.c:sys_fdatasync(). */ +static int fsync_sub(struct lun *curlun) +{ + struct file *filp = curlun->filp; + struct inode *inode; + int rc, err; + + if (curlun->ro || !filp) + return 0; + if (!filp->f_op->fsync) + return -EINVAL; + + inode = filp->f_dentry->d_inode; + down(&inode->i_sem); + current->flags |= PF_SYNCWRITE; + rc = filemap_fdatawrite(inode->i_mapping); + err = filp->f_op->fsync(filp, filp->f_dentry, 1); + if (!rc) + rc = err; + err = filemap_fdatawait(inode->i_mapping); + if (!rc) + rc = err; + current->flags &= ~PF_SYNCWRITE; + up(&inode->i_sem); + VLDBG(curlun, "fdatasync -> %d\n", rc); + return rc; +} + +static void fsync_all(struct fsg_dev *fsg) +{ + int i; + + for (i = 0; i < fsg->nluns; ++i) + fsync_sub(&fsg->luns[i]); +} + +static int do_synchronize_cache(struct fsg_dev *fsg) +{ + struct lun *curlun = fsg->curlun; + int rc; + + /* We ignore the requested LBA and write out all file's + * dirty data buffers. */ + rc = fsync_sub(curlun); + if (rc) + curlun->sense_data = SS_WRITE_ERROR; + return 0; +} + + +/*-------------------------------------------------------------------------*/ + +static void invalidate_sub(struct lun *curlun) +{ + struct file *filp = curlun->filp; + struct inode *inode = filp->f_dentry->d_inode; + unsigned long rc; + + rc = invalidate_inode_pages(inode->i_mapping); + VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc); +} + +static int do_verify(struct fsg_dev *fsg) +{ + struct 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_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_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 << 9; + file_offset = ((loff_t) lba) << 9; + + /* Write out all the dirty buffers before invalidating them */ + 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. + * If this means reading 0 then we were asked to read + * past the end of 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 >> 9; + 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 -= (nread & 511); // Round down to a sector + } + if (nread == 0) { + curlun->sense_data = SS_UNRECOVERED_READ_ERROR; + curlun->sense_data_info = file_offset >> 9; + 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_id[] = "File-Stor Gadget"; + + if (!fsg->curlun) { // Unsupported LUNs are okay + fsg->bad_lun_okay = 1; + memset(buf, 0, 36); + buf[0] = 0x7f; // Unsupported, no device-type + return 36; + } + + memset(buf, 0, 8); // Non-removable, direct-access device + 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, product_id, + mod_data.release); + return 36; +} + + +static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{ + struct lun *curlun = fsg->curlun; + u8 *buf = (u8 *) bh->buf; + u32 sd, sdinfo; + + /* + * 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; + } else { + sd = curlun->sense_data; + sdinfo = curlun->sense_data_info; + curlun->sense_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + } + + memset(buf, 0, 18); + buf[0] = 0x80 | 0x70; // Valid, current error + buf[2] = SK(sd); + put_be32(&buf[3], sdinfo); // 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 lun *curlun = fsg->curlun; + u32 lba = get_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_be32(&buf[0], curlun->num_sectors - 1); // Max logical block + put_be32(&buf[4], 512); // Block length + return 8; +} + + +static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{ + struct 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 == SC_MODE_SENSE_6) { + buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA + buf += 4; + limit = 255; + } else { // SC_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_be16(&buf[4], 0xffff); // Don't disable prefetch + // Minimum prefetch = 0 + put_be16(&buf[8], 0xffff); // Maximum prefetch + put_be16(&buf[10], 0xffff); // 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 == SC_MODE_SENSE_6) + buf0[0] = len - 1; + else + put_be16(buf0, len - 2); + return len; +} + + +static int do_start_stop(struct fsg_dev *fsg) +{ + struct 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); + close_backing_file(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 (!backing_file_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 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) + 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 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_be32(&buf[0], curlun->num_sectors); // Number of blocks + put_be32(&buf[4], 512); // Block length + buf[4] = 0x02; // Current capacity + return 12; +} + + +static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh) +{ + struct 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) { + WARN(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 pad_with_zeros(struct fsg_dev *fsg) +{ + struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; + u32 nkeep = bh->inreq->length; + u32 nsend; + int rc; + + bh->state = BUF_STATE_EMPTY; // For the first iteration + fsg->usb_amount_left = nkeep + fsg->residue; + while (fsg->usb_amount_left > 0) { + + /* Wait for the next buffer to be free */ + while (bh->state != BUF_STATE_EMPTY) { + if ((rc = sleep_thread(fsg)) != 0) + return rc; + } + + nsend = min(fsg->usb_amount_left, (u32) mod_data.buflen); + memset(bh->buf + nkeep, 0, nsend - nkeep); + bh->inreq->length = nsend; + bh->inreq->zero = 0; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + bh = fsg->next_buffhd_to_fill = bh->next; + fsg->usb_amount_left -= nsend; + nkeep = 0; + } + return 0; +} + +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) { + 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->outreq->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); + + /* amount is always divisible by 512, hence by + * the bulk-out maxpacket size */ + bh->outreq->length = bh->bulk_out_intended_length = + 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 */ + if ((rc = sleep_thread(fsg)) != 0) + 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, if we're allowed to stall then send the + * short packet and halt the bulk-in endpoint. If we can't + * stall, pad out the remaining data with 0's. */ + else { + if (mod_data.can_stall) { + bh->inreq->zero = 1; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + fsg->next_buffhd_to_fill = bh->next; + rc = halt_bulk_in_endpoint(fsg); + } else + rc = pad_with_zeros(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 lun *curlun = fsg->curlun; + struct fsg_buffhd *bh; + int rc; + u8 status = USB_STATUS_PASS; + u32 sd, sdinfo = 0; + + /* Wait for the next buffer to become available */ + bh = fsg->next_buffhd_to_fill; + while (bh->state != BUF_STATE_EMPTY) { + if ((rc = sleep_thread(fsg)) != 0) + 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 = USB_STATUS_PHASE_ERROR; + sd = SS_INVALID_COMMAND; + } else if (sd != SS_NO_SENSE) { + DBG(fsg, "sending command-failure status\n"); + status = USB_STATUS_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 = (struct bulk_cs_wrap *) bh->buf; + + /* Store and send the Bulk-only CSW */ + csw->Signature = __constant_cpu_to_le32(USB_BULK_CS_SIG); + csw->Tag = fsg->tag; + csw->Residue = cpu_to_le32(fsg->residue); + csw->Status = status; + + bh->inreq->length = USB_BULK_CS_WRAP_LEN; + bh->inreq->zero = 0; + start_transfer(fsg, fsg->bulk_in, bh->inreq, + &bh->inreq_busy, &bh->state); + + } 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 = (struct interrupt_data *) + 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->dma = bh->inreq->dma; + 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 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: MS-Windows issues REQUEST SENSE + * with cbw->Length == 12 (it should be 6). */ + if (fsg->cmnd[0] == SC_REQUEST_SENSE && fsg->cmnd_size == 12) + cmnd_size = fsg->cmnd_size; + else { + fsg->phase_error = 1; + return -EINVAL; + } + } + + /* Check that the LUN values are oonsistent */ + if (transport_is_bbb()) { + if (fsg->lun != lun) + DBG(fsg, "using LUN %d from CBW, " + "not LUN %d from CDB\n", + fsg->lun, lun); + } else + fsg->lun = lun; // Use LUN from the command + + /* Check the LUN */ + if (fsg->lun >= 0 && fsg->lun < fsg->nluns) { + fsg->curlun = curlun = &fsg->luns[fsg->lun]; + if (fsg->cmnd[0] != SC_REQUEST_SENSE) { + curlun->sense_data = SS_NO_SENSE; + curlun->sense_data_info = 0; + } + } else { + fsg->curlun = curlun = NULL; + 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] != SC_INQUIRY && + fsg->cmnd[0] != SC_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] != SC_INQUIRY && + fsg->cmnd[0] != SC_REQUEST_SENSE) { + curlun->sense_data = curlun->unit_attention_data; + curlun->unit_attention_data = SS_NO_SENSE; + return -EINVAL; + } + + /* Check that only command bytes listed in the mask are non-zero */ + 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 && !backing_file_is_open(curlun) && needs_medium) { + curlun->sense_data = SS_MEDIUM_NOT_PRESENT; + return -EINVAL; + } + + return 0; +} + + +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) { + if ((rc = sleep_thread(fsg)) != 0) + 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 SC_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 SC_MODE_SELECT_6: + 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 SC_MODE_SELECT_10: + fsg->data_size_from_cmnd = get_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 SC_MODE_SENSE_6: + 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 SC_MODE_SENSE_10: + fsg->data_size_from_cmnd = get_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 SC_PREVENT_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 SC_READ_6: + i = fsg->cmnd[4]; + fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; + if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, + (7<<1) | (1<<4), 1, + "READ(6)")) == 0) + reply = do_read(fsg); + break; + + case SC_READ_10: + fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9; + if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "READ(10)")) == 0) + reply = do_read(fsg); + break; + + case SC_READ_12: + fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9; + if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST, + (1<<1) | (0xf<<2) | (0xf<<6), 1, + "READ(12)")) == 0) + reply = do_read(fsg); + break; + + case SC_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 SC_READ_FORMAT_CAPACITIES: + fsg->data_size_from_cmnd = get_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 SC_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 SC_START_STOP_UNIT: + 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 SC_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 SC_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 SC_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 SC_WRITE_6: + i = fsg->cmnd[4]; + fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; + if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, + (7<<1) | (1<<4), 1, + "WRITE(6)")) == 0) + reply = do_write(fsg); + break; + + case SC_WRITE_10: + fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9; + if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, + (1<<1) | (0xf<<2) | (3<<7), 1, + "WRITE(10)")) == 0) + reply = do_write(fsg); + break; + + case SC_WRITE_12: + fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9; + if ((reply = check_command(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 SC_FORMAT_UNIT: + case SC_RELEASE: + case SC_RESERVE: + case SC_SEND_DIAGNOSTIC: + // Fall through + + default: + 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, 0xff, 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 = (struct bulk_cb_wrap *) req->buf; + + /* Was this a real packet? */ + if (req->status) + return -EINVAL; + + /* Is the CBW valid? */ + if (req->actual != USB_BULK_CB_WRAP_LEN || + cbw->Signature != __constant_cpu_to_le32( + USB_BULK_CB_SIG)) { + 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 bulk pipes! + * If we want to avoid stalls, set a flag so that we will + * clear the endpoint halts at the next reset. */ + if (!mod_data.can_stall) + set_bit(CLEAR_BULK_HALTS, &fsg->atomic_bitflags); + fsg_set_halt(fsg, fsg->bulk_out); + halt_bulk_in_endpoint(fsg); + return -EINVAL; + } + + /* Is the CBW meaningful? */ + if (cbw->Lun >= MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG || + cbw->Length < 6 || 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 & USB_BULK_IN_FLAG) + 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) { + if ((rc = sleep_thread(fsg)) != 0) + return rc; + } + + /* Queue a request to read a Bulk-only CBW */ + set_bulk_out_req_length(fsg, bh, USB_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) { + if ((rc = sleep_thread(fsg)) != 0) + return rc; + } + 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) { + if ((rc = sleep_thread(fsg)) != 0) + 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); + } + 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; + rc = usb_ep_enable(ep, d); + 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 < 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 = ep_desc(fsg->gadget, &fs_bulk_in_desc, &hs_bulk_in_desc); + if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0) + goto reset; + fsg->bulk_in_enabled = 1; + + d = ep_desc(fsg->gadget, &fs_bulk_out_desc, &hs_bulk_out_desc); + if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0) + goto reset; + fsg->bulk_out_enabled = 1; + fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize); + + if (transport_is_cbi()) { + d = ep_desc(fsg->gadget, &fs_intr_in_desc, &hs_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 < 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->dma = bh->outreq->dma = bh->dma; + 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 { + char *speed; + + switch (fsg->gadget->speed) { + case USB_SPEED_LOW: speed = "low"; break; + case USB_SPEED_FULL: speed = "full"; break; + case USB_SPEED_HIGH: speed = "high"; break; + default: speed = "?"; break; + } + INFO(fsg, "%s speed config #%d\n", 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 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, &fsg->thread_signal_mask, + &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 < 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 < 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 < 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; + } + 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(CLEAR_BULK_HALTS, + &fsg->atomic_bitflags)) { + usb_ep_clear_halt(fsg->bulk_in); + usb_ep_clear_halt(fsg->bulk_out); + } + + 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: + fsync_all(fsg); + 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 = (struct fsg_dev *) fsg_; + + fsg->thread_task = current; + + /* Release all our userspace resources */ + daemonize("file-storage-gadget"); + + /* Allow the thread to be killed by a signal, but set the signal mask + * to block everything but INT, TERM, KILL, and USR1. */ + siginitsetinv(&fsg->thread_signal_mask, sigmask(SIGINT) | + sigmask(SIGTERM) | sigmask(SIGKILL) | + sigmask(SIGUSR1)); + sigprocmask(SIG_SETMASK, &fsg->thread_signal_mask, NULL); + + /* 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()); + + /* Wait for the gadget registration to finish up */ + wait_for_completion(&fsg->thread_notifier); + + /* 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); + } + + fsg->thread_task = NULL; + flush_signals(current); + + /* In case we are exiting because of a signal, unregister the + * gadget driver and close the backing file. */ + if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) { + usb_gadget_unregister_driver(&fsg_driver); + close_all_backing_files(fsg); + } + + /* Let the unbind and cleanup routines know the thread has exited */ + complete_and_exit(&fsg->thread_notifier, 0); +} + + +/*-------------------------------------------------------------------------*/ + +/* If the next two routines are called while the gadget is registered, + * the caller must own fsg->filesem for writing. */ + +static int open_backing_file(struct lun *curlun, const char *filename) +{ + int ro; + struct file *filp = NULL; + int rc = -EINVAL; + struct inode *inode = NULL; + loff_t size; + loff_t num_sectors; + + /* R/W if we can, R/O if we must */ + ro = curlun->ro; + if (!ro) { + filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0); + if (-EROFS == PTR_ERR(filp)) + ro = 1; + } + if (ro) + filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0); + if (IS_ERR(filp)) { + LINFO(curlun, "unable to open backing file: %s\n", filename); + return PTR_ERR(filp); + } + + if (!(filp->f_mode & FMODE_WRITE)) + ro = 1; + + if (filp->f_dentry) + inode = filp->f_dentry->d_inode; + if (inode && S_ISBLK(inode->i_mode)) { + if (bdev_read_only(inode->i_bdev)) + ro = 1; + } else if (!inode || !S_ISREG(inode->i_mode)) { + LINFO(curlun, "invalid file type: %s\n", filename); + goto out; + } + + /* If we can't read the file, it's no good. + * If we can't write the file, use it read-only. */ + if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) { + LINFO(curlun, "file not readable: %s\n", filename); + goto out; + } + if (!(filp->f_op->write || filp->f_op->aio_write)) + ro = 1; + + size = i_size_read(inode->i_mapping->host); + if (size < 0) { + LINFO(curlun, "unable to find file size: %s\n", filename); + rc = (int) size; + goto out; + } + num_sectors = size >> 9; // File size in 512-byte sectors + if (num_sectors == 0) { + LINFO(curlun, "file too small: %s\n", filename); + rc = -ETOOSMALL; + goto out; + } + + get_file(filp); + curlun->ro = ro; + curlun->filp = filp; + curlun->file_length = size; + curlun->num_sectors = num_sectors; + LDBG(curlun, "open backing file: %s\n", filename); + rc = 0; + +out: + filp_close(filp, current->files); + return rc; +} + + +static void close_backing_file(struct lun *curlun) +{ + if (curlun->filp) { + LDBG(curlun, "close backing file\n"); + fput(curlun->filp); + curlun->filp = NULL; + } +} + +static void close_all_backing_files(struct fsg_dev *fsg) +{ + int i; + + for (i = 0; i < fsg->nluns; ++i) + close_backing_file(&fsg->luns[i]); +} + + +static ssize_t show_ro(struct device *dev, char *buf) +{ + struct lun *curlun = dev_to_lun(dev); + + return sprintf(buf, "%d\n", curlun->ro); +} + +static ssize_t show_file(struct device *dev, char *buf) +{ + struct lun *curlun = dev_to_lun(dev); + struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev); + char *p; + ssize_t rc; + + down_read(&fsg->filesem); + if (backing_file_is_open(curlun)) { // Get the complete pathname + p = d_path(curlun->filp->f_dentry, curlun->filp->f_vfsmnt, + buf, PAGE_SIZE - 1); + if (IS_ERR(p)) + rc = PTR_ERR(p); + else { + rc = strlen(p); + memmove(buf, p, rc); + buf[rc] = '\n'; // Add a newline + buf[++rc] = 0; + } + } else { // No file, return 0 bytes + *buf = 0; + rc = 0; + } + up_read(&fsg->filesem); + return rc; +} + + +static ssize_t store_ro(struct device *dev, const char *buf, size_t count) +{ + ssize_t rc = count; + struct lun *curlun = dev_to_lun(dev); + struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev); + int i; + + if (sscanf(buf, "%d", &i) != 1) + return -EINVAL; + + /* Allow the write-enable status to change only while the backing file + * is closed. */ + down_read(&fsg->filesem); + if (backing_file_is_open(curlun)) { + LDBG(curlun, "read-only status change prevented\n"); + rc = -EBUSY; + } else { + curlun->ro = !!i; + LDBG(curlun, "read-only status set to %d\n", curlun->ro); + } + up_read(&fsg->filesem); + return rc; +} + +static ssize_t store_file(struct device *dev, const char *buf, size_t count) +{ + struct lun *curlun = dev_to_lun(dev); + struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev); + int rc = 0; + + if (curlun->prevent_medium_removal && backing_file_is_open(curlun)) { + LDBG(curlun, "eject attempt prevented\n"); + return -EBUSY; // "Door is locked" + } + + /* Remove a trailing newline */ + if (count > 0 && buf[count-1] == '\n') + ((char *) buf)[count-1] = 0; // Ugh! + + /* Eject current medium */ + down_write(&fsg->filesem); + if (backing_file_is_open(curlun)) { + close_backing_file(curlun); + curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT; + } + + /* Load new medium */ + if (count > 0 && buf[0]) { + rc = open_backing_file(curlun, buf); + if (rc == 0) + curlun->unit_attention_data = + SS_NOT_READY_TO_READY_TRANSITION; + } + up_write(&fsg->filesem); + return (rc < 0 ? rc : count); +} + + +/* The write permissions and store_xxx pointers are set in fsg_bind() */ +static DEVICE_ATTR(ro, 0444, show_ro, NULL); +static DEVICE_ATTR(file, 0444, show_file, NULL); + + +/*-------------------------------------------------------------------------*/ + +static void lun_release(struct device *dev) +{ + struct fsg_dev *fsg = (struct fsg_dev *) dev_get_drvdata(dev); + + complete(&fsg->lun_released); +} + +static void fsg_unbind(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = get_gadget_data(gadget); + int i; + struct lun *curlun; + struct usb_request *req = fsg->ep0req; + + DBG(fsg, "unbind\n"); + clear_bit(REGISTERED, &fsg->atomic_bitflags); + + /* Unregister the sysfs attribute files and the LUNs */ + init_completion(&fsg->lun_released); + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + if (curlun->registered) { + device_remove_file(&curlun->dev, &dev_attr_ro); + device_remove_file(&curlun->dev, &dev_attr_file); + device_unregister(&curlun->dev); + wait_for_completion(&fsg->lun_released); + curlun->registered = 0; + } + } + + /* 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); + } + + /* Free the data buffers */ + for (i = 0; i < NUM_BUFFERS; ++i) { + struct fsg_buffhd *bh = &fsg->buffhds[i]; + + if (bh->buf) + usb_ep_free_buffer(fsg->bulk_in, bh->buf, bh->dma, + mod_data.buflen); + } + + /* Free the request and buffer for endpoint 0 */ + if (req) { + if (req->buf) + usb_ep_free_buffer(fsg->ep0, req->buf, + req->dma, EP0_BUFSIZE); + usb_ep_free_request(fsg->ep0, req); + } + + set_gadget_data(gadget, NULL); +} + + +static int __init check_parameters(struct fsg_dev *fsg) +{ + int prot; + + /* 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"; + + if (gadget_is_sh(fsg->gadget)) + mod_data.can_stall = 0; + + if (mod_data.release == 0xffff) { // Parameter wasn't set + if (gadget_is_net2280(fsg->gadget)) + mod_data.release = 0x0301; + else if (gadget_is_dummy(fsg->gadget)) + mod_data.release = 0x0302; + else if (gadget_is_pxa(fsg->gadget)) + mod_data.release = 0x0303; + else if (gadget_is_sh(fsg->gadget)) + mod_data.release = 0x0304; + + /* The sa1100 controller is not supported */ + + else if (gadget_is_goku(fsg->gadget)) + mod_data.release = 0x0306; + else if (gadget_is_mq11xx(fsg->gadget)) + mod_data.release = 0x0307; + else if (gadget_is_omap(fsg->gadget)) + mod_data.release = 0x0308; + else if (gadget_is_lh7a40x(fsg->gadget)) + mod_data.release = 0x0309; + else if (gadget_is_n9604(fsg->gadget)) + mod_data.release = 0x0310; + else if (gadget_is_pxa27x(fsg->gadget)) + mod_data.release = 0x0311; + else if (gadget_is_s3c2410(gadget)) + mod_data.release = 0x0312; + else if (gadget_is_at91(fsg->gadget)) + mod_data.release = 0x0313; + else { + WARN(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 */ + + return 0; +} + + +static int __init fsg_bind(struct usb_gadget *gadget) +{ + struct fsg_dev *fsg = the_fsg; + int rc; + int i; + struct 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_ro.attr.mode = dev_attr_file.attr.mode = 0644; + dev_attr_ro.store = store_ro; + dev_attr_file.store = store_file; + } + + /* Find out how many LUNs there should be */ + i = mod_data.nluns; + if (i == 0) + i = max(mod_data.num_filenames, 1); + if (i > 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 = kmalloc(i * sizeof(struct lun), GFP_KERNEL); + if (!fsg->luns) { + rc = -ENOMEM; + goto out; + } + memset(fsg->luns, 0, i * sizeof(struct lun)); + fsg->nluns = i; + + for (i = 0; i < fsg->nluns; ++i) { + curlun = &fsg->luns[i]; + curlun->ro = ro[i]; + curlun->dev.parent = &gadget->dev; + curlun->dev.driver = &fsg_driver.driver; + dev_set_drvdata(&curlun->dev, fsg); + snprintf(curlun->dev.bus_id, BUS_ID_SIZE, + "%s-lun%d", gadget->dev.bus_id, i); + + if ((rc = device_register(&curlun->dev)) != 0) + INFO(fsg, "failed to register LUN%d: %d\n", i, rc); + else { + curlun->registered = 1; + curlun->dev.release = lun_release; + device_create_file(&curlun->dev, &dev_attr_ro); + device_create_file(&curlun->dev, &dev_attr_file); + } + + if (file[i] && *file[i]) { + if ((rc = open_backing_file(curlun, file[i])) != 0) + 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, &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, &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, &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.bMaxPacketSize0 = fsg->ep0->maxpacket; + 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 + intf_desc.bNumEndpoints = i; + intf_desc.bInterfaceSubClass = mod_data.protocol_type; + intf_desc.bInterfaceProtocol = mod_data.transport_type; + fs_function[i + FS_FUNCTION_PRE_EP_ENTRIES] = NULL; + +#ifdef CONFIG_USB_GADGET_DUALSPEED + hs_function[i + HS_FUNCTION_PRE_EP_ENTRIES] = NULL; + + /* Assume ep0 uses the same maxpacket value for both speeds */ + dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket; + + /* Assume that all endpoint addresses are the same for both speeds */ + hs_bulk_in_desc.bEndpointAddress = fs_bulk_in_desc.bEndpointAddress; + hs_bulk_out_desc.bEndpointAddress = fs_bulk_out_desc.bEndpointAddress; + hs_intr_in_desc.bEndpointAddress = fs_intr_in_desc.bEndpointAddress; +#endif + + if (gadget->is_otg) { + otg_desc.bmAttributes |= USB_OTG_HNP, + config_desc.bmAttributes |= USB_CONFIG_ATT_WAKEUP; + } + + 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 = usb_ep_alloc_buffer(fsg->ep0, EP0_BUFSIZE, + &req->dma, GFP_KERNEL); + if (!req->buf) + goto out; + req->complete = ep0_complete; + + /* Allocate the data buffers */ + for (i = 0; i < NUM_BUFFERS; ++i) { + struct fsg_buffhd *bh = &fsg->buffhds[i]; + + bh->buf = usb_ep_alloc_buffer(fsg->bulk_in, mod_data.buflen, + &bh->dma, GFP_KERNEL); + if (!bh->buf) + goto out; + bh->next = bh + 1; + } + fsg->buffhds[NUM_BUFFERS - 1].next = &fsg->buffhds[0]; + + /* This should reflect the actual gadget power source */ + usb_gadget_set_selfpowered(gadget); + + snprintf(manufacturer, sizeof manufacturer, "%s %s with %s", + system_utsname.sysname, system_utsname.release, + gadget->name); + + /* On a real device, serial[] would be loaded from permanent + * storage. We just encode it from the driver version string. */ + for (i = 0; i < sizeof(serial) - 2; i += 2) { + unsigned char c = DRIVER_VERSION[i / 2]; + + if (!c) + break; + sprintf(&serial[i], "%02X", c); + } + + if ((rc = kernel_thread(fsg_main_thread, fsg, (CLONE_VM | CLONE_FS | + CLONE_FILES))) < 0) + goto out; + fsg->thread_pid = rc; + + INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\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 (backing_file_is_open(curlun)) { + p = NULL; + if (pathbuf) { + p = d_path(curlun->filp->f_dentry, + curlun->filp->f_vfsmnt, + pathbuf, PATH_MAX); + if (IS_ERR(p)) + p = NULL; + } + LINFO(curlun, "ro=%d, file: %s\n", + curlun->ro, (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, buflen=%u\n", + mod_data.removable, mod_data.can_stall, + mod_data.buflen); + DBG(fsg, "I/O thread pid: %d\n", fsg->thread_pid); + 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); + close_all_backing_files(fsg); + 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 = { +#ifdef CONFIG_USB_GADGET_DUALSPEED + .speed = USB_SPEED_HIGH, +#else + .speed = USB_SPEED_FULL, +#endif + .function = (char *) longname, + .bind = fsg_bind, + .unbind = fsg_unbind, + .disconnect = fsg_disconnect, + .setup = fsg_setup, + .suspend = fsg_suspend, + .resume = fsg_resume, + + .driver = { + .name = (char *) shortname, + // .release = ... + // .suspend = ... + // .resume = ... + }, +}; + + +static int __init fsg_alloc(void) +{ + struct fsg_dev *fsg; + + fsg = kmalloc(sizeof *fsg, GFP_KERNEL); + if (!fsg) + return -ENOMEM; + memset(fsg, 0, sizeof *fsg); + spin_lock_init(&fsg->lock); + init_rwsem(&fsg->filesem); + init_waitqueue_head(&fsg->thread_wqh); + init_completion(&fsg->thread_notifier); + + the_fsg = fsg; + return 0; +} + + +static void fsg_free(struct fsg_dev *fsg) +{ + kfree(fsg->luns); + kfree(fsg); +} + + +static int __init fsg_init(void) +{ + int rc; + struct fsg_dev *fsg; + + if ((rc = fsg_alloc()) != 0) + return rc; + fsg = the_fsg; + if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0) { + fsg_free(fsg); + return rc; + } + set_bit(REGISTERED, &fsg->atomic_bitflags); + + /* Tell the thread to start working */ + complete(&fsg->thread_notifier); + return 0; +} +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); + + close_all_backing_files(fsg); + fsg_free(fsg); +} +module_exit(fsg_cleanup); |