drivers/usb/gadget/file_storage.c

   1 /*
   2  * file_storage.c -- File-backed USB Storage Gadget, for USB development
   3  *
   4  * Copyright (C) 2003-2008 Alan Stern
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions, and the following disclaimer,
  12  *    without modification.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. The names of the above-listed copyright holders may not be used
  17  *    to endorse or promote products derived from this software without
  18  *    specific prior written permission.
  19  *
  20  * ALTERNATIVELY, this software may be distributed under the terms of the
  21  * GNU General Public License ("GPL") as published by the Free Software
  22  * Foundation, either version 2 of that License or (at your option) any
  23  * later version.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  26  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  27  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  28  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  29  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  30  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  31  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  32  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  33  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  34  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  35  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38
  39 /*
  40  * The File-backed Storage Gadget acts as a USB Mass Storage device,
  41  * appearing to the host as a disk drive or as a CD-ROM drive.  In addition
  42  * to providing an example of a genuinely useful gadget driver for a USB
  43  * device, it also illustrates a technique of double-buffering for increased
  44  * throughput.  Last but not least, it gives an easy way to probe the
  45  * behavior of the Mass Storage drivers in a USB host.
  46  *
  47  * Backing storage is provided by a regular file or a block device, specified
  48  * by the "file" module parameter.  Access can be limited to read-only by
  49  * setting the optional "ro" module parameter.  (For CD-ROM emulation,
  50  * access is always read-only.)  The gadget will indicate that it has
  51  * removable media if the optional "removable" module parameter is set.
  52  *
  53  * The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI),
  54  * and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected
  55  * by the optional "transport" module parameter.  It also supports the
  56  * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03),
  57  * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by
  58  * the optional "protocol" module parameter.  In addition, the default
  59  * Vendor ID, Product ID, and release number can be overridden.
  60  *
  61  * There is support for multiple logical units (LUNs), each of which has
  62  * its own backing file.  The number of LUNs can be set using the optional
  63  * "luns" module parameter (anywhere from 1 to 8), and the corresponding
  64  * files are specified using comma-separated lists for "file" and "ro".
  65  * The default number of LUNs is taken from the number of "file" elements;
  66  * it is 1 if "file" is not given.  If "removable" is not set then a backing
  67  * file must be specified for each LUN.  If it is set, then an unspecified
  68  * or empty backing filename means the LUN's medium is not loaded.  Ideally
  69  * each LUN would be settable independently as a disk drive or a CD-ROM
  70  * drive, but currently all LUNs have to be the same type.  The CD-ROM
  71  * emulation includes a single data track and no audio tracks; hence there
  72  * need be only one backing file per LUN.  Note also that the CD-ROM block
  73  * length is set to 512 rather than the more common value 2048.
  74  *
  75  * Requirements are modest; only a bulk-in and a bulk-out endpoint are
  76  * needed (an interrupt-out endpoint is also needed for CBI).  The memory
  77  * requirement amounts to two 16K buffers, size configurable by a parameter.
  78  * Support is included for both full-speed and high-speed operation.
  79  *
  80  * Note that the driver is slightly non-portable in that it assumes a
  81  * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
  82  * interrupt-in endpoints.  With most device controllers this isn't an
  83  * issue, but there may be some with hardware restrictions that prevent
  84  * a buffer from being used by more than one endpoint.
  85  *
  86  * Module options:
  87  *
  88  *      file=filename[,filename...]
  89  *                              Required if "removable" is not set, names of
  90  *                                      the files or block devices used for
  91  *                                      backing storage
  92  *      ro=b[,b...]             Default false, booleans for read-only access
  93  *      removable               Default false, boolean for removable media
  94  *      luns=N                  Default N = number of filenames, number of
  95  *                                      LUNs to support
  96  *      stall                   Default determined according to the type of
  97  *                                      USB device controller (usually true),
  98  *                                      boolean to permit the driver to halt
  99  *                                      bulk endpoints
 100  *      cdrom                   Default false, boolean for whether to emulate
 101  *                                      a CD-ROM drive
 102  *      transport=XXX           Default BBB, transport name (CB, CBI, or BBB)
 103  *      protocol=YYY            Default SCSI, protocol name (RBC, 8020 or
 104  *                                      ATAPI, QIC, UFI, 8070, or SCSI;
 105  *                                      also 1 - 6)
 106  *      vendor=0xVVVV           Default 0x0525 (NetChip), USB Vendor ID
 107  *      product=0xPPPP          Default 0xa4a5 (FSG), USB Product ID
 108  *      release=0xRRRR          Override the USB release number (bcdDevice)
 109  *      buflen=N                Default N=16384, buffer size used (will be
 110  *                                      rounded down to a multiple of
 111  *                                      PAGE_CACHE_SIZE)
 112  *
 113  * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro",
 114  * "removable", "luns", "stall", and "cdrom" options are available; default
 115  * values are used for everything else.
 116  *
 117  * The pathnames of the backing files and the ro settings are available in
 118  * the attribute files "file" and "ro" in the lun<n> subdirectory of the
 119  * gadget's sysfs directory.  If the "removable" option is set, writing to
 120  * these files will simulate ejecting/loading the medium (writing an empty
 121  * line means eject) and adjusting a write-enable tab.  Changes to the ro
 122  * setting are not allowed when the medium is loaded or if CD-ROM emulation
 123  * is being used.
 124  *
 125  * This gadget driver is heavily based on "Gadget Zero" by David Brownell.
 126  * The driver's SCSI command interface was based on the "Information
 127  * technology - Small Computer System Interface - 2" document from
 128  * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at
 129  * <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.  The single exception
 130  * is opcode 0x23 (READ FORMAT CAPACITIES), which was based on the
 131  * "Universal Serial Bus Mass Storage Class UFI Command Specification"
 132  * document, Revision 1.0, December 14, 1998, available at
 133  * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
 134  */
 135
 136
 137 /*
 138  *                              Driver Design
 139  *
 140  * The FSG driver is fairly straightforward.  There is a main kernel
 141  * thread that handles most of the work.  Interrupt routines field
 142  * callbacks from the controller driver: bulk- and interrupt-request
 143  * completion notifications, endpoint-0 events, and disconnect events.
 144  * Completion events are passed to the main thread by wakeup calls.  Many
 145  * ep0 requests are handled at interrupt time, but SetInterface,
 146  * SetConfiguration, and device reset requests are forwarded to the
 147  * thread in the form of "exceptions" using SIGUSR1 signals (since they
 148  * should interrupt any ongoing file I/O operations).
 149  *
 150  * The thread's main routine implements the standard command/data/status
 151  * parts of a SCSI interaction.  It and its subroutines are full of tests
 152  * for pending signals/exceptions -- all this polling is necessary since
 153  * the kernel has no setjmp/longjmp equivalents.  (Maybe this is an
 154  * indication that the driver really wants to be running in userspace.)
 155  * An important point is that so long as the thread is alive it keeps an
 156  * open reference to the backing file.  This will prevent unmounting
 157  * the backing file's underlying filesystem and could cause problems
 158  * during system shutdown, for example.  To prevent such problems, the
 159  * thread catches INT, TERM, and KILL signals and converts them into
 160  * an EXIT exception.
 161  *
 162  * In normal operation the main thread is started during the gadget's
 163  * fsg_bind() callback and stopped during fsg_unbind().  But it can also
 164  * exit when it receives a signal, and there's no point leaving the
 165  * gadget running when the thread is dead.  So just before the thread
 166  * exits, it deregisters the gadget driver.  This makes things a little
 167  * tricky: The driver is deregistered at two places, and the exiting
 168  * thread can indirectly call fsg_unbind() which in turn can tell the
 169  * thread to exit.  The first problem is resolved through the use of the
 170  * REGISTERED atomic bitflag; the driver will only be deregistered once.
 171  * The second problem is resolved by having fsg_unbind() check
 172  * fsg->state; it won't try to stop the thread if the state is already
 173  * FSG_STATE_TERMINATED.
 174  *
 175  * To provide maximum throughput, the driver uses a circular pipeline of
 176  * buffer heads (struct fsg_buffhd).  In principle the pipeline can be
 177  * arbitrarily long; in practice the benefits don't justify having more
 178  * than 2 stages (i.e., double buffering).  But it helps to think of the
 179  * pipeline as being a long one.  Each buffer head contains a bulk-in and
 180  * a bulk-out request pointer (since the buffer can be used for both
 181  * output and input -- directions always are given from the host's
 182  * point of view) as well as a pointer to the buffer and various state
 183  * variables.
 184  *
 185  * Use of the pipeline follows a simple protocol.  There is a variable
 186  * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
 187  * At any time that buffer head may still be in use from an earlier
 188  * request, so each buffer head has a state variable indicating whether
 189  * it is EMPTY, FULL, or BUSY.  Typical use involves waiting for the
 190  * buffer head to be EMPTY, filling the buffer either by file I/O or by
 191  * USB I/O (during which the buffer head is BUSY), and marking the buffer
 192  * head FULL when the I/O is complete.  Then the buffer will be emptied
 193  * (again possibly by USB I/O, during which it is marked BUSY) and
 194  * finally marked EMPTY again (possibly by a completion routine).
 195  *
 196  * A module parameter tells the driver to avoid stalling the bulk
 197  * endpoints wherever the transport specification allows.  This is
 198  * necessary for some UDCs like the SuperH, which cannot reliably clear a
 199  * halt on a bulk endpoint.  However, under certain circumstances the
 200  * Bulk-only specification requires a stall.  In such cases the driver
 201  * will halt the endpoint and set a flag indicating that it should clear
 202  * the halt in software during the next device reset.  Hopefully this
 203  * will permit everything to work correctly.  Furthermore, although the
 204  * specification allows the bulk-out endpoint to halt when the host sends
 205  * too much data, implementing this would cause an unavoidable race.
 206  * The driver will always use the "no-stall" approach for OUT transfers.
 207  *
 208  * One subtle point concerns sending status-stage responses for ep0
 209  * requests.  Some of these requests, such as device reset, can involve
 210  * interrupting an ongoing file I/O operation, which might take an
 211  * arbitrarily long time.  During that delay the host might give up on
 212  * the original ep0 request and issue a new one.  When that happens the
 213  * driver should not notify the host about completion of the original
 214  * request, as the host will no longer be waiting for it.  So the driver
 215  * assigns to each ep0 request a unique tag, and it keeps track of the
 216  * tag value of the request associated with a long-running exception
 217  * (device-reset, interface-change, or configuration-change).  When the
 218  * exception handler is finished, the status-stage response is submitted
 219  * only if the current ep0 request tag is equal to the exception request
 220  * tag.  Thus only the most recently received ep0 request will get a
 221  * status-stage response.
 222  *
 223  * Warning: This driver source file is too long.  It ought to be split up
 224  * into a header file plus about 3 separate .c files, to handle the details
 225  * of the Gadget, USB Mass Storage, and SCSI protocols.
 226  */
 227
 228
 229 /* #define VERBOSE_DEBUG */
 230 /* #define DUMP_MSGS */
 231
 232
 233 #include <linux/blkdev.h>
 234 #include <linux/completion.h>
 235 #include <linux/dcache.h>
 236 #include <linux/delay.h>
 237 #include <linux/device.h>
 238 #include <linux/fcntl.h>
 239 #include <linux/file.h>
 240 #include <linux/fs.h>
 241 #include <linux/kref.h>
 242 #include <linux/kthread.h>
 243 #include <linux/limits.h>
 244 #include <linux/rwsem.h>
 245 #include <linux/slab.h>
 246 #include <linux/spinlock.h>
 247 #include <linux/string.h>
 248 #include <linux/freezer.h>
 249 #include <linux/utsname.h>
 250
 251 #include <linux/usb/ch9.h>
 252 #include <linux/usb/gadget.h>
 253
 254 #include "gadget_chips.h"
 255
 256
 257
 258 /*
 259  * Kbuild is not very cooperative with respect to linking separately
 260  * compiled library objects into one module.  So for now we won't use
 261  * separate compilation ... ensuring init/exit sections work to shrink
 262  * the runtime footprint, and giving us at least some parts of what
 263  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
 264  */
 265 #include "usbstring.c"
 266 #include "config.c"
 267 #include "epautoconf.c"
 268
 269 /*-------------------------------------------------------------------------*/
 270
 271 #define DRIVER_DESC             "File-backed Storage Gadget"
 272 #define DRIVER_NAME             "g_file_storage"
 273 #define DRIVER_VERSION          "20 November 2008"
 274
 275 static const char longname[] = DRIVER_DESC;
 276 static const char shortname[] = DRIVER_NAME;
 277
 278 MODULE_DESCRIPTION(DRIVER_DESC);
 279 MODULE_AUTHOR("Alan Stern");
 280 MODULE_LICENSE("Dual BSD/GPL");
 281
 282 /* Thanks to NetChip Technologies for donating this product ID.
 283  *
 284  * DO NOT REUSE THESE IDs with any other driver!!  Ever!!
 285  * Instead:  allocate your own, using normal USB-IF procedures. */
 286 #define DRIVER_VENDOR_ID        0x0525  // NetChip
 287 #define DRIVER_PRODUCT_ID       0xa4a5  // Linux-USB File-backed Storage Gadget
 288
 289
 290 /*
 291  * This driver assumes self-powered hardware and has no way for users to
 292  * trigger remote wakeup.  It uses autoconfiguration to select endpoints
 293  * and endpoint addresses.
 294  */
 295
 296
 297 /*-------------------------------------------------------------------------*/
 298
 299 #define LDBG(lun,fmt,args...) \
 300         dev_dbg(&(lun)->dev , fmt , ## args)
 301 #define MDBG(fmt,args...) \
 302         pr_debug(DRIVER_NAME ": " fmt , ## args)
 303
 304 #ifndef DEBUG
 305 #undef VERBOSE_DEBUG
 306 #undef DUMP_MSGS
 307 #endif /* !DEBUG */
 308
 309 #ifdef VERBOSE_DEBUG
 310 #define VLDBG   LDBG
 311 #else
 312 #define VLDBG(lun,fmt,args...) \
 313         do { } while (0)
 314 #endif /* VERBOSE_DEBUG */
 315
 316 #define LERROR(lun,fmt,args...) \
 317         dev_err(&(lun)->dev , fmt , ## args)
 318 #define LWARN(lun,fmt,args...) \
 319         dev_warn(&(lun)->dev , fmt , ## args)
 320 #define LINFO(lun,fmt,args...) \
 321         dev_info(&(lun)->dev , fmt , ## args)
 322
 323 #define MINFO(fmt,args...) \
 324         pr_info(DRIVER_NAME ": " fmt , ## args)
 325
 326 #define DBG(d, fmt, args...) \
 327         dev_dbg(&(d)->gadget->dev , fmt , ## args)
 328 #define VDBG(d, fmt, args...) \
 329         dev_vdbg(&(d)->gadget->dev , fmt , ## args)
 330 #define ERROR(d, fmt, args...) \
 331         dev_err(&(d)->gadget->dev , fmt , ## args)
 332 #define WARNING(d, fmt, args...) \
 333         dev_warn(&(d)->gadget->dev , fmt , ## args)
 334 #define INFO(d, fmt, args...) \
 335         dev_info(&(d)->gadget->dev , fmt , ## args)
 336
 337
 338 /*-------------------------------------------------------------------------*/
 339
 340 /* Encapsulate the module parameter settings */
 341
 342 #define MAX_LUNS        8
 343
 344 static struct {
 345         char            *file[MAX_LUNS];
 346         int             ro[MAX_LUNS];
 347         unsigned int    num_filenames;
 348         unsigned int    num_ros;
 349         unsigned int    nluns;
 350
 351         int             removable;
 352         int             can_stall;
 353         int             cdrom;
 354
 355         char            *transport_parm;
 356         char            *protocol_parm;
 357         unsigned short  vendor;
 358         unsigned short  product;
 359         unsigned short  release;
 360         unsigned int    buflen;
 361
 362         int             transport_type;
 363         char            *transport_name;
 364         int             protocol_type;
 365         char            *protocol_name;
 366
 367 } mod_data = {                                  // Default values
 368         .transport_parm         = "BBB",
 369         .protocol_parm          = "SCSI",
 370         .removable              = 0,
 371         .can_stall              = 1,
 372         .cdrom                  = 0,
 373         .vendor                 = DRIVER_VENDOR_ID,
 374         .product                = DRIVER_PRODUCT_ID,
 375         .release                = 0xffff,       // Use controller chip type
 376         .buflen                 = 16384,
 377         };
 378
 379
 380 module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
 381                 S_IRUGO);
 382 MODULE_PARM_DESC(file, "names of backing files or devices");
 383
 384 module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
 385 MODULE_PARM_DESC(ro, "true to force read-only");
 386
 387 module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
 388 MODULE_PARM_DESC(luns, "number of LUNs");
 389
 390 module_param_named(removable, mod_data.removable, bool, S_IRUGO);
 391 MODULE_PARM_DESC(removable, "true to simulate removable media");
 392
 393 module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
 394 MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
 395
 396 module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
 397 MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
 398
 399
 400 /* In the non-TEST version, only the module parameters listed above
 401  * are available. */
 402 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 403
 404 module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
 405 MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
 406
 407 module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
 408 MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
 409                 "8070, or SCSI)");
 410
 411 module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
 412 MODULE_PARM_DESC(vendor, "USB Vendor ID");
 413
 414 module_param_named(product, mod_data.product, ushort, S_IRUGO);
 415 MODULE_PARM_DESC(product, "USB Product ID");
 416
 417 module_param_named(release, mod_data.release, ushort, S_IRUGO);
 418 MODULE_PARM_DESC(release, "USB release number");
 419
 420 module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
 421 MODULE_PARM_DESC(buflen, "I/O buffer size");
 422
 423 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 424
 425
 426 /*-------------------------------------------------------------------------*/
 427
 428 /* SCSI device types */
 429 #define TYPE_DISK       0x00
 430 #define TYPE_CDROM      0x05
 431
 432 /* USB protocol value = the transport method */
 433 #define USB_PR_CBI      0x00            // Control/Bulk/Interrupt
 434 #define USB_PR_CB       0x01            // Control/Bulk w/o interrupt
 435 #define USB_PR_BULK     0x50            // Bulk-only
 436
 437 /* USB subclass value = the protocol encapsulation */
 438 #define USB_SC_RBC      0x01            // Reduced Block Commands (flash)
 439 #define USB_SC_8020     0x02            // SFF-8020i, MMC-2, ATAPI (CD-ROM)
 440 #define USB_SC_QIC      0x03            // QIC-157 (tape)
 441 #define USB_SC_UFI      0x04            // UFI (floppy)
 442 #define USB_SC_8070     0x05            // SFF-8070i (removable)
 443 #define USB_SC_SCSI     0x06            // Transparent SCSI
 444
 445 /* Bulk-only data structures */
 446
 447 /* Command Block Wrapper */
 448 struct bulk_cb_wrap {
 449         __le32  Signature;              // Contains 'USBC'
 450         u32     Tag;                    // Unique per command id
 451         __le32  DataTransferLength;     // Size of the data
 452         u8      Flags;                  // Direction in bit 7
 453         u8      Lun;                    // LUN (normally 0)
 454         u8      Length;                 // Of the CDB, <= MAX_COMMAND_SIZE
 455         u8      CDB[16];                // Command Data Block
 456 };
 457
 458 #define USB_BULK_CB_WRAP_LEN    31
 459 #define USB_BULK_CB_SIG         0x43425355      // Spells out USBC
 460 #define USB_BULK_IN_FLAG        0x80
 461
 462 /* Command Status Wrapper */
 463 struct bulk_cs_wrap {
 464         __le32  Signature;              // Should = 'USBS'
 465         u32     Tag;                    // Same as original command
 466         __le32  Residue;                // Amount not transferred
 467         u8      Status;                 // See below
 468 };
 469
 470 #define USB_BULK_CS_WRAP_LEN    13
 471 #define USB_BULK_CS_SIG         0x53425355      // Spells out 'USBS'
 472 #define USB_STATUS_PASS         0
 473 #define USB_STATUS_FAIL         1
 474 #define USB_STATUS_PHASE_ERROR  2
 475
 476 /* Bulk-only class specific requests */
 477 #define USB_BULK_RESET_REQUEST          0xff
 478 #define USB_BULK_GET_MAX_LUN_REQUEST    0xfe
 479
 480
 481 /* CBI Interrupt data structure */
 482 struct interrupt_data {
 483         u8      bType;
 484         u8      bValue;
 485 };
 486
 487 #define CBI_INTERRUPT_DATA_LEN          2
 488
 489 /* CBI Accept Device-Specific Command request */
 490 #define USB_CBI_ADSC_REQUEST            0x00
 491
 492
 493 #define MAX_COMMAND_SIZE        16      // Length of a SCSI Command Data Block
 494
 495 /* SCSI commands that we recognize */
 496 #define SC_FORMAT_UNIT                  0x04
 497 #define SC_INQUIRY                      0x12
 498 #define SC_MODE_SELECT_6                0x15
 499 #define SC_MODE_SELECT_10               0x55
 500 #define SC_MODE_SENSE_6                 0x1a
 501 #define SC_MODE_SENSE_10                0x5a
 502 #define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
 503 #define SC_READ_6                       0x08
 504 #define SC_READ_10                      0x28
 505 #define SC_READ_12                      0xa8
 506 #define SC_READ_CAPACITY                0x25
 507 #define SC_READ_FORMAT_CAPACITIES       0x23
 508 #define SC_READ_HEADER                  0x44
 509 #define SC_READ_TOC                     0x43
 510 #define SC_RELEASE                      0x17
 511 #define SC_REQUEST_SENSE                0x03
 512 #define SC_RESERVE                      0x16
 513 #define SC_SEND_DIAGNOSTIC              0x1d
 514 #define SC_START_STOP_UNIT              0x1b
 515 #define SC_SYNCHRONIZE_CACHE            0x35
 516 #define SC_TEST_UNIT_READY              0x00
 517 #define SC_VERIFY                       0x2f
 518 #define SC_WRITE_6                      0x0a
 519 #define SC_WRITE_10                     0x2a
 520 #define SC_WRITE_12                     0xaa
 521
 522 /* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
 523 #define SS_NO_SENSE                             0
 524 #define SS_COMMUNICATION_FAILURE                0x040800
 525 #define SS_INVALID_COMMAND                      0x052000
 526 #define SS_INVALID_FIELD_IN_CDB                 0x052400
 527 #define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE   0x052100
 528 #define SS_LOGICAL_UNIT_NOT_SUPPORTED           0x052500
 529 #define SS_MEDIUM_NOT_PRESENT                   0x023a00
 530 #define SS_MEDIUM_REMOVAL_PREVENTED             0x055302
 531 #define SS_NOT_READY_TO_READY_TRANSITION        0x062800
 532 #define SS_RESET_OCCURRED                       0x062900
 533 #define SS_SAVING_PARAMETERS_NOT_SUPPORTED      0x053900
 534 #define SS_UNRECOVERED_READ_ERROR               0x031100
 535 #define SS_WRITE_ERROR                          0x030c02
 536 #define SS_WRITE_PROTECTED                      0x072700
 537
 538 #define SK(x)           ((u8) ((x) >> 16))      // Sense Key byte, etc.
 539 #define ASC(x)          ((u8) ((x) >> 8))
 540 #define ASCQ(x)         ((u8) (x))
 541
 542
 543 /*-------------------------------------------------------------------------*/
 544
 545 /*
 546  * These definitions will permit the compiler to avoid generating code for
 547  * parts of the driver that aren't used in the non-TEST version.  Even gcc
 548  * can recognize when a test of a constant expression yields a dead code
 549  * path.
 550  */
 551
 552 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 553
 554 #define transport_is_bbb()      (mod_data.transport_type == USB_PR_BULK)
 555 #define transport_is_cbi()      (mod_data.transport_type == USB_PR_CBI)
 556 #define protocol_is_scsi()      (mod_data.protocol_type == USB_SC_SCSI)
 557
 558 #else
 559
 560 #define transport_is_bbb()      1
 561 #define transport_is_cbi()      0
 562 #define protocol_is_scsi()      1
 563
 564 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 565
 566
 567 struct lun {
 568         struct file     *filp;
 569         loff_t          file_length;
 570         loff_t          num_sectors;
 571
 572         unsigned int    ro : 1;
 573         unsigned int    prevent_medium_removal : 1;
 574         unsigned int    registered : 1;
 575         unsigned int    info_valid : 1;
 576
 577         u32             sense_data;
 578         u32             sense_data_info;
 579         u32             unit_attention_data;
 580
 581         struct device   dev;
 582 };
 583
 584 #define backing_file_is_open(curlun)    ((curlun)->filp != NULL)
 585
 586 static struct lun *dev_to_lun(struct device *dev)
 587 {
 588         return container_of(dev, struct lun, dev);
 589 }
 590
 591
 592 /* Big enough to hold our biggest descriptor */
 593 #define EP0_BUFSIZE     256
 594 #define DELAYED_STATUS  (EP0_BUFSIZE + 999)     // An impossibly large value
 595
 596 /* Number of buffers we will use.  2 is enough for double-buffering */
 597 #define NUM_BUFFERS     2
 598
 599 enum fsg_buffer_state {
 600         BUF_STATE_EMPTY = 0,
 601         BUF_STATE_FULL,
 602         BUF_STATE_BUSY
 603 };
 604
 605 struct fsg_buffhd {
 606         void                            *buf;
 607         enum fsg_buffer_state           state;
 608         struct fsg_buffhd               *next;
 609
 610         /* The NetChip 2280 is faster, and handles some protocol faults
 611          * better, if we don't submit any short bulk-out read requests.
 612          * So we will record the intended request length here. */
 613         unsigned int                    bulk_out_intended_length;
 614
 615         struct usb_request              *inreq;
 616         int                             inreq_busy;
 617         struct usb_request              *outreq;
 618         int                             outreq_busy;
 619 };
 620
 621 enum fsg_state {
 622         FSG_STATE_COMMAND_PHASE = -10,          // This one isn't used anywhere
 623         FSG_STATE_DATA_PHASE,
 624         FSG_STATE_STATUS_PHASE,
 625
 626         FSG_STATE_IDLE = 0,
 627         FSG_STATE_ABORT_BULK_OUT,
 628         FSG_STATE_RESET,
 629         FSG_STATE_INTERFACE_CHANGE,
 630         FSG_STATE_CONFIG_CHANGE,
 631         FSG_STATE_DISCONNECT,
 632         FSG_STATE_EXIT,
 633         FSG_STATE_TERMINATED
 634 };
 635
 636 enum data_direction {
 637         DATA_DIR_UNKNOWN = 0,
 638         DATA_DIR_FROM_HOST,
 639         DATA_DIR_TO_HOST,
 640         DATA_DIR_NONE
 641 };
 642
 643 struct fsg_dev {
 644         /* lock protects: state, all the req_busy's, and cbbuf_cmnd */
 645         spinlock_t              lock;
 646         struct usb_gadget       *gadget;
 647
 648         /* filesem protects: backing files in use */
 649         struct rw_semaphore     filesem;
 650
 651         /* reference counting: wait until all LUNs are released */
 652         struct kref             ref;
 653
 654         struct usb_ep           *ep0;           // Handy copy of gadget->ep0
 655         struct usb_request      *ep0req;        // For control responses
 656         unsigned int            ep0_req_tag;
 657         const char              *ep0req_name;
 658
 659         struct usb_request      *intreq;        // For interrupt responses
 660         int                     intreq_busy;
 661         struct fsg_buffhd       *intr_buffhd;
 662
 663         unsigned int            bulk_out_maxpacket;
 664         enum fsg_state          state;          // For exception handling
 665         unsigned int            exception_req_tag;
 666
 667         u8                      config, new_config;
 668
 669         unsigned int            running : 1;
 670         unsigned int            bulk_in_enabled : 1;
 671         unsigned int            bulk_out_enabled : 1;
 672         unsigned int            intr_in_enabled : 1;
 673         unsigned int            phase_error : 1;
 674         unsigned int            short_packet_received : 1;
 675         unsigned int            bad_lun_okay : 1;
 676
 677         unsigned long           atomic_bitflags;
 678 #define REGISTERED              0
 679 #define IGNORE_BULK_OUT         1
 680 #define SUSPENDED               2
 681
 682         struct usb_ep           *bulk_in;
 683         struct usb_ep           *bulk_out;
 684         struct usb_ep           *intr_in;
 685
 686         struct fsg_buffhd       *next_buffhd_to_fill;
 687         struct fsg_buffhd       *next_buffhd_to_drain;
 688         struct fsg_buffhd       buffhds[NUM_BUFFERS];
 689
 690         int                     thread_wakeup_needed;
 691         struct completion       thread_notifier;
 692         struct task_struct      *thread_task;
 693
 694         int                     cmnd_size;
 695         u8                      cmnd[MAX_COMMAND_SIZE];
 696         enum data_direction     data_dir;
 697         u32                     data_size;
 698         u32                     data_size_from_cmnd;
 699         u32                     tag;
 700         unsigned int            lun;
 701         u32                     residue;
 702         u32                     usb_amount_left;
 703
 704         /* The CB protocol offers no way for a host to know when a command
 705          * has completed.  As a result the next command may arrive early,
 706          * and we will still have to handle it.  For that reason we need
 707          * a buffer to store new commands when using CB (or CBI, which
 708          * does not oblige a host to wait for command completion either). */
 709         int                     cbbuf_cmnd_size;
 710         u8                      cbbuf_cmnd[MAX_COMMAND_SIZE];
 711
 712         unsigned int            nluns;
 713         struct lun              *luns;
 714         struct lun              *curlun;
 715 };
 716
 717 typedef void (*fsg_routine_t)(struct fsg_dev *);
 718
 719 static int exception_in_progress(struct fsg_dev *fsg)
 720 {
 721         return (fsg->state > FSG_STATE_IDLE);
 722 }
 723
 724 /* Make bulk-out requests be divisible by the maxpacket size */
 725 static void set_bulk_out_req_length(struct fsg_dev *fsg,
 726                 struct fsg_buffhd *bh, unsigned int length)
 727 {
 728         unsigned int    rem;
 729
 730         bh->bulk_out_intended_length = length;
 731         rem = length % fsg->bulk_out_maxpacket;
 732         if (rem > 0)
 733                 length += fsg->bulk_out_maxpacket - rem;
 734         bh->outreq->length = length;
 735 }
 736
 737 static struct fsg_dev                   *the_fsg;
 738 static struct usb_gadget_driver         fsg_driver;
 739
 740 static void     close_backing_file(struct lun *curlun);
 741 static void     close_all_backing_files(struct fsg_dev *fsg);
 742
 743
 744 /*-------------------------------------------------------------------------*/
 745
 746 #ifdef DUMP_MSGS
 747
 748 static void dump_msg(struct fsg_dev *fsg, const char *label,
 749                 const u8 *buf, unsigned int length)
 750 {
 751         if (length < 512) {
 752                 DBG(fsg, "%s, length %u:\n", label, length);
 753                 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
 754                                 16, 1, buf, length, 0);
 755         }
 756 }
 757
 758 static void dump_cdb(struct fsg_dev *fsg)
 759 {}
 760
 761 #else
 762
 763 static void dump_msg(struct fsg_dev *fsg, const char *label,
 764                 const u8 *buf, unsigned int length)
 765 {}
 766
 767 #ifdef VERBOSE_DEBUG
 768
 769 static void dump_cdb(struct fsg_dev *fsg)
 770 {
 771         print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,
 772                         16, 1, fsg->cmnd, fsg->cmnd_size, 0);
 773 }
 774
 775 #else
 776
 777 static void dump_cdb(struct fsg_dev *fsg)
 778 {}
 779
 780 #endif /* VERBOSE_DEBUG */
 781 #endif /* DUMP_MSGS */
 782
 783
 784 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 785 {
 786         const char      *name;
 787
 788         if (ep == fsg->bulk_in)
 789                 name = "bulk-in";
 790         else if (ep == fsg->bulk_out)
 791                 name = "bulk-out";
 792         else
 793                 name = ep->name;
 794         DBG(fsg, "%s set halt\n", name);
 795         return usb_ep_set_halt(ep);
 796 }
 797
 798
 799 /*-------------------------------------------------------------------------*/
 800
 801 /* Routines for unaligned data access */
 802
 803 static u16 get_be16(u8 *buf)
 804 {
 805         return ((u16) buf[0] << 8) | ((u16) buf[1]);
 806 }
 807
 808 static u32 get_be32(u8 *buf)
 809 {
 810         return ((u32) buf[0] << 24) | ((u32) buf[1] << 16) |
 811                         ((u32) buf[2] << 8) | ((u32) buf[3]);
 812 }
 813
 814 static void put_be16(u8 *buf, u16 val)
 815 {
 816         buf[0] = val >> 8;
 817         buf[1] = val;
 818 }
 819
 820 static void put_be32(u8 *buf, u32 val)
 821 {
 822         buf[0] = val >> 24;
 823         buf[1] = val >> 16;
 824         buf[2] = val >> 8;
 825         buf[3] = val & 0xff;
 826 }
 827
 828
 829 /*-------------------------------------------------------------------------*/
 830
 831 /*
 832  * DESCRIPTORS ... most are static, but strings and (full) configuration
 833  * descriptors are built on demand.  Also the (static) config and interface
 834  * descriptors are adjusted during fsg_bind().
 835  */
 836 #define STRING_MANUFACTURER     1
 837 #define STRING_PRODUCT          2
 838 #define STRING_SERIAL           3
 839 #define STRING_CONFIG           4
 840 #define STRING_INTERFACE        5
 841
 842 /* There is only one configuration. */
 843 #define CONFIG_VALUE            1
 844
 845 static struct usb_device_descriptor
 846 device_desc = {
 847         .bLength =              sizeof device_desc,
 848         .bDescriptorType =      USB_DT_DEVICE,
 849
 850         .bcdUSB =               __constant_cpu_to_le16(0x0200),
 851         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 852
 853         /* The next three values can be overridden by module parameters */
 854         .idVendor =             __constant_cpu_to_le16(DRIVER_VENDOR_ID),
 855         .idProduct =            __constant_cpu_to_le16(DRIVER_PRODUCT_ID),
 856         .bcdDevice =            __constant_cpu_to_le16(0xffff),
 857
 858         .iManufacturer =        STRING_MANUFACTURER,
 859         .iProduct =             STRING_PRODUCT,
 860         .iSerialNumber =        STRING_SERIAL,
 861         .bNumConfigurations =   1,
 862 };
 863
 864 static struct usb_config_descriptor
 865 config_desc = {
 866         .bLength =              sizeof config_desc,
 867         .bDescriptorType =      USB_DT_CONFIG,
 868
 869         /* wTotalLength computed by usb_gadget_config_buf() */
 870         .bNumInterfaces =       1,
 871         .bConfigurationValue =  CONFIG_VALUE,
 872         .iConfiguration =       STRING_CONFIG,
 873         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 874         .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 875 };
 876
 877 static struct usb_otg_descriptor
 878 otg_desc = {
 879         .bLength =              sizeof(otg_desc),
 880         .bDescriptorType =      USB_DT_OTG,
 881
 882         .bmAttributes =         USB_OTG_SRP,
 883 };
 884
 885 /* There is only one interface. */
 886
 887 static struct usb_interface_descriptor
 888 intf_desc = {
 889         .bLength =              sizeof intf_desc,
 890         .bDescriptorType =      USB_DT_INTERFACE,
 891
 892         .bNumEndpoints =        2,              // Adjusted during fsg_bind()
 893         .bInterfaceClass =      USB_CLASS_MASS_STORAGE,
 894         .bInterfaceSubClass =   USB_SC_SCSI,    // Adjusted during fsg_bind()
 895         .bInterfaceProtocol =   USB_PR_BULK,    // Adjusted during fsg_bind()
 896         .iInterface =           STRING_INTERFACE,
 897 };
 898
 899 /* Three full-speed endpoint descriptors: bulk-in, bulk-out,
 900  * and interrupt-in. */
 901
 902 static struct usb_endpoint_descriptor
 903 fs_bulk_in_desc = {
 904         .bLength =              USB_DT_ENDPOINT_SIZE,
 905         .bDescriptorType =      USB_DT_ENDPOINT,
 906
 907         .bEndpointAddress =     USB_DIR_IN,
 908         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 909         /* wMaxPacketSize set by autoconfiguration */
 910 };
 911
 912 static struct usb_endpoint_descriptor
 913 fs_bulk_out_desc = {
 914         .bLength =              USB_DT_ENDPOINT_SIZE,
 915         .bDescriptorType =      USB_DT_ENDPOINT,
 916
 917         .bEndpointAddress =     USB_DIR_OUT,
 918         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 919         /* wMaxPacketSize set by autoconfiguration */
 920 };
 921
 922 static struct usb_endpoint_descriptor
 923 fs_intr_in_desc = {
 924         .bLength =              USB_DT_ENDPOINT_SIZE,
 925         .bDescriptorType =      USB_DT_ENDPOINT,
 926
 927         .bEndpointAddress =     USB_DIR_IN,
 928         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 929         .wMaxPacketSize =       __constant_cpu_to_le16(2),
 930         .bInterval =            32,     // frames -> 32 ms
 931 };
 932
 933 static const struct usb_descriptor_header *fs_function[] = {
 934         (struct usb_descriptor_header *) &otg_desc,
 935         (struct usb_descriptor_header *) &intf_desc,
 936         (struct usb_descriptor_header *) &fs_bulk_in_desc,
 937         (struct usb_descriptor_header *) &fs_bulk_out_desc,
 938         (struct usb_descriptor_header *) &fs_intr_in_desc,
 939         NULL,
 940 };
 941 #define FS_FUNCTION_PRE_EP_ENTRIES      2
 942
 943
 944 /*
 945  * USB 2.0 devices need to expose both high speed and full speed
 946  * descriptors, unless they only run at full speed.
 947  *
 948  * That means alternate endpoint descriptors (bigger packets)
 949  * and a "device qualifier" ... plus more construction options
 950  * for the config descriptor.
 951  */
 952 static struct usb_qualifier_descriptor
 953 dev_qualifier = {
 954         .bLength =              sizeof dev_qualifier,
 955         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 956
 957         .bcdUSB =               __constant_cpu_to_le16(0x0200),
 958         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 959
 960         .bNumConfigurations =   1,
 961 };
 962
 963 static struct usb_endpoint_descriptor
 964 hs_bulk_in_desc = {
 965         .bLength =              USB_DT_ENDPOINT_SIZE,
 966         .bDescriptorType =      USB_DT_ENDPOINT,
 967
 968         /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
 969         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 970         .wMaxPacketSize =       __constant_cpu_to_le16(512),
 971 };
 972
 973 static struct usb_endpoint_descriptor
 974 hs_bulk_out_desc = {
 975         .bLength =              USB_DT_ENDPOINT_SIZE,
 976         .bDescriptorType =      USB_DT_ENDPOINT,
 977
 978         /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
 979         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 980         .wMaxPacketSize =       __constant_cpu_to_le16(512),
 981         .bInterval =            1,      // NAK every 1 uframe
 982 };
 983
 984 static struct usb_endpoint_descriptor
 985 hs_intr_in_desc = {
 986         .bLength =              USB_DT_ENDPOINT_SIZE,
 987         .bDescriptorType =      USB_DT_ENDPOINT,
 988
 989         /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
 990         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 991         .wMaxPacketSize =       __constant_cpu_to_le16(2),
 992         .bInterval =            9,      // 2**(9-1) = 256 uframes -> 32 ms
 993 };
 994
 995 static const struct usb_descriptor_header *hs_function[] = {
 996         (struct usb_descriptor_header *) &otg_desc,
 997         (struct usb_descriptor_header *) &intf_desc,
 998         (struct usb_descriptor_header *) &hs_bulk_in_desc,
 999         (struct usb_descriptor_header *) &hs_bulk_out_desc,
1000         (struct usb_descriptor_header *) &hs_intr_in_desc,
1001         NULL,
1002 };
1003 #define HS_FUNCTION_PRE_EP_ENTRIES      2
1004
1005 /* Maxpacket and other transfer characteristics vary by speed. */
1006 static struct usb_endpoint_descriptor *
1007 ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
1008                 struct usb_endpoint_descriptor *hs)
1009 {
1010         if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
1011                 return hs;
1012         return fs;
1013 }
1014
1015
1016 /* The CBI specification limits the serial string to 12 uppercase hexadecimal
1017  * characters. */
1018 static char                             manufacturer[64];
1019 static char                             serial[13];
1020
1021 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
1022 static struct usb_string                strings[] = {
1023         {STRING_MANUFACTURER,   manufacturer},
1024         {STRING_PRODUCT,        longname},
1025         {STRING_SERIAL,         serial},
1026         {STRING_CONFIG,         "Self-powered"},
1027         {STRING_INTERFACE,      "Mass Storage"},
1028         {}
1029 };
1030
1031 static struct usb_gadget_strings        stringtab = {
1032         .language       = 0x0409,               // en-us
1033         .strings        = strings,
1034 };
1035
1036
1037 /*
1038  * Config descriptors must agree with the code that sets configurations
1039  * and with code managing interfaces and their altsettings.  They must
1040  * also handle different speeds and other-speed requests.
1041  */
1042 static int populate_config_buf(struct usb_gadget *gadget,
1043                 u8 *buf, u8 type, unsigned index)
1044 {
1045         enum usb_device_speed                   speed = gadget->speed;
1046         int                                     len;
1047         const struct usb_descriptor_header      **function;
1048
1049         if (index > 0)
1050                 return -EINVAL;
1051
1052         if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
1053                 speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
1054         if (gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH)
1055                 function = hs_function;
1056         else
1057                 function = fs_function;
1058
1059         /* for now, don't advertise srp-only devices */
1060         if (!gadget_is_otg(gadget))
1061                 function++;
1062
1063         len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
1064         ((struct usb_config_descriptor *) buf)->bDescriptorType = type;
1065         return len;
1066 }
1067
1068
1069 /*-------------------------------------------------------------------------*/
1070
1071 /* These routines may be called in process context or in_irq */
1072
1073 /* Caller must hold fsg->lock */
1074 static void wakeup_thread(struct fsg_dev *fsg)
1075 {
1076         /* Tell the main thread that something has happened */
1077         fsg->thread_wakeup_needed = 1;
1078         if (fsg->thread_task)
1079                 wake_up_process(fsg->thread_task);
1080 }
1081
1082
1083 static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
1084 {
1085         unsigned long           flags;
1086
1087         /* Do nothing if a higher-priority exception is already in progress.
1088          * If a lower-or-equal priority exception is in progress, preempt it
1089          * and notify the main thread by sending it a signal. */
1090         spin_lock_irqsave(&fsg->lock, flags);
1091         if (fsg->state <= new_state) {
1092                 fsg->exception_req_tag = fsg->ep0_req_tag;
1093                 fsg->state = new_state;
1094                 if (fsg->thread_task)
1095                         send_sig_info(SIGUSR1, SEND_SIG_FORCED,
1096                                         fsg->thread_task);
1097         }
1098         spin_unlock_irqrestore(&fsg->lock, flags);
1099 }
1100
1101
1102 /*-------------------------------------------------------------------------*/
1103
1104 /* The disconnect callback and ep0 routines.  These always run in_irq,
1105  * except that ep0_queue() is called in the main thread to acknowledge
1106  * completion of various requests: set config, set interface, and
1107  * Bulk-only device reset. */
1108
1109 static void fsg_disconnect(struct usb_gadget *gadget)
1110 {
1111         struct fsg_dev          *fsg = get_gadget_data(gadget);
1112
1113         DBG(fsg, "disconnect or port reset\n");
1114         raise_exception(fsg, FSG_STATE_DISCONNECT);
1115 }
1116
1117
1118 static int ep0_queue(struct fsg_dev *fsg)
1119 {
1120         int     rc;
1121
1122         rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
1123         if (rc != 0 && rc != -ESHUTDOWN) {
1124
1125                 /* We can't do much more than wait for a reset */
1126                 WARNING(fsg, "error in submission: %s --> %d\n",
1127                                 fsg->ep0->name, rc);
1128         }
1129         return rc;
1130 }
1131
1132 static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
1133 {
1134         struct fsg_dev          *fsg = ep->driver_data;
1135
1136         if (req->actual > 0)
1137                 dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
1138         if (req->status || req->actual != req->length)
1139                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
1140                                 req->status, req->actual, req->length);
1141         if (req->status == -ECONNRESET)         // Request was cancelled
1142                 usb_ep_fifo_flush(ep);
1143
1144         if (req->status == 0 && req->context)
1145                 ((fsg_routine_t) (req->context))(fsg);
1146 }
1147
1148
1149 /*-------------------------------------------------------------------------*/
1150
1151 /* Bulk and interrupt endpoint completion handlers.
1152  * These always run in_irq. */
1153
1154 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
1155 {
1156         struct fsg_dev          *fsg = ep->driver_data;
1157         struct fsg_buffhd       *bh = req->context;
1158
1159         if (req->status || req->actual != req->length)
1160                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
1161                                 req->status, req->actual, req->length);
1162         if (req->status == -ECONNRESET)         // Request was cancelled
1163                 usb_ep_fifo_flush(ep);
1164
1165         /* Hold the lock while we update the request and buffer states */
1166         smp_wmb();
1167         spin_lock(&fsg->lock);
1168         bh->inreq_busy = 0;
1169         bh->state = BUF_STATE_EMPTY;
1170         wakeup_thread(fsg);
1171         spin_unlock(&fsg->lock);
1172 }
1173
1174 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
1175 {
1176         struct fsg_dev          *fsg = ep->driver_data;
1177         struct fsg_buffhd       *bh = req->context;
1178
1179         dump_msg(fsg, "bulk-out", req->buf, req->actual);
1180         if (req->status || req->actual != bh->bulk_out_intended_length)
1181                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
1182                                 req->status, req->actual,
1183                                 bh->bulk_out_intended_length);
1184         if (req->status == -ECONNRESET)         // Request was cancelled
1185                 usb_ep_fifo_flush(ep);
1186
1187         /* Hold the lock while we update the request and buffer states */
1188         smp_wmb();
1189         spin_lock(&fsg->lock);
1190         bh->outreq_busy = 0;
1191         bh->state = BUF_STATE_FULL;
1192         wakeup_thread(fsg);
1193         spin_unlock(&fsg->lock);
1194 }
1195
1196
1197 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1198 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
1199 {
1200         struct fsg_dev          *fsg = ep->driver_data;
1201         struct fsg_buffhd       *bh = req->context;
1202
1203         if (req->status || req->actual != req->length)
1204                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
1205                                 req->status, req->actual, req->length);
1206         if (req->status == -ECONNRESET)         // Request was cancelled
1207                 usb_ep_fifo_flush(ep);
1208
1209         /* Hold the lock while we update the request and buffer states */
1210         smp_wmb();
1211         spin_lock(&fsg->lock);
1212         fsg->intreq_busy = 0;
1213         bh->state = BUF_STATE_EMPTY;
1214         wakeup_thread(fsg);
1215         spin_unlock(&fsg->lock);
1216 }
1217
1218 #else
1219 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
1220 {}
1221 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
1222
1223
1224 /*-------------------------------------------------------------------------*/
1225
1226 /* Ep0 class-specific handlers.  These always run in_irq. */
1227
1228 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1229 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1230 {
1231         struct usb_request      *req = fsg->ep0req;
1232         static u8               cbi_reset_cmnd[6] = {
1233                         SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
1234
1235         /* Error in command transfer? */
1236         if (req->status || req->length != req->actual ||
1237                         req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
1238
1239                 /* Not all controllers allow a protocol stall after
1240                  * receiving control-out data, but we'll try anyway. */
1241                 fsg_set_halt(fsg, fsg->ep0);
1242                 return;                 // Wait for reset
1243         }
1244
1245         /* Is it the special reset command? */
1246         if (req->actual >= sizeof cbi_reset_cmnd &&
1247                         memcmp(req->buf, cbi_reset_cmnd,
1248                                 sizeof cbi_reset_cmnd) == 0) {
1249
1250                 /* Raise an exception to stop the current operation
1251                  * and reinitialize our state. */
1252                 DBG(fsg, "cbi reset request\n");
1253                 raise_exception(fsg, FSG_STATE_RESET);
1254                 return;
1255         }
1256
1257         VDBG(fsg, "CB[I] accept device-specific command\n");
1258         spin_lock(&fsg->lock);
1259
1260         /* Save the command for later */
1261         if (fsg->cbbuf_cmnd_size)
1262                 WARNING(fsg, "CB[I] overwriting previous command\n");
1263         fsg->cbbuf_cmnd_size = req->actual;
1264         memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
1265
1266         wakeup_thread(fsg);
1267         spin_unlock(&fsg->lock);
1268 }
1269
1270 #else
1271 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1272 {}
1273 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
1274
1275
1276 static int class_setup_req(struct fsg_dev *fsg,
1277                 const struct usb_ctrlrequest *ctrl)
1278 {
1279         struct usb_request      *req = fsg->ep0req;
1280         int                     value = -EOPNOTSUPP;
1281         u16                     w_index = le16_to_cpu(ctrl->wIndex);
1282         u16                     w_value = le16_to_cpu(ctrl->wValue);
1283         u16                     w_length = le16_to_cpu(ctrl->wLength);
1284
1285         if (!fsg->config)
1286                 return value;
1287
1288         /* Handle Bulk-only class-specific requests */
1289         if (transport_is_bbb()) {
1290                 switch (ctrl->bRequest) {
1291
1292                 case USB_BULK_RESET_REQUEST:
1293                         if (ctrl->bRequestType != (USB_DIR_OUT |
1294                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1295                                 break;
1296                         if (w_index != 0 || w_value != 0) {
1297                                 value = -EDOM;
1298                                 break;
1299                         }
1300
1301                         /* Raise an exception to stop the current operation
1302                          * and reinitialize our state. */
1303                         DBG(fsg, "bulk reset request\n");
1304                         raise_exception(fsg, FSG_STATE_RESET);
1305                         value = DELAYED_STATUS;
1306                         break;
1307
1308                 case USB_BULK_GET_MAX_LUN_REQUEST:
1309                         if (ctrl->bRequestType != (USB_DIR_IN |
1310                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1311                                 break;
1312                         if (w_index != 0 || w_value != 0) {
1313                                 value = -EDOM;
1314                                 break;
1315                         }
1316                         VDBG(fsg, "get max LUN\n");
1317                         *(u8 *) req->buf = fsg->nluns - 1;
1318                         value = 1;
1319                         break;
1320                 }
1321         }
1322
1323         /* Handle CBI class-specific requests */
1324         else {
1325                 switch (ctrl->bRequest) {
1326
1327                 case USB_CBI_ADSC_REQUEST:
1328                         if (ctrl->bRequestType != (USB_DIR_OUT |
1329                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1330                                 break;
1331                         if (w_index != 0 || w_value != 0) {
1332                                 value = -EDOM;
1333                                 break;
1334                         }
1335                         if (w_length > MAX_COMMAND_SIZE) {
1336                                 value = -EOVERFLOW;
1337                                 break;
1338                         }
1339                         value = w_length;
1340                         fsg->ep0req->context = received_cbi_adsc;
1341                         break;
1342                 }
1343         }
1344
1345         if (value == -EOPNOTSUPP)
1346                 VDBG(fsg,
1347                         "unknown class-specific control req "
1348                         "%02x.%02x v%04x i%04x l%u\n",
1349                         ctrl->bRequestType, ctrl->bRequest,
1350                         le16_to_cpu(ctrl->wValue), w_index, w_length);
1351         return value;
1352 }
1353
1354
1355 /*-------------------------------------------------------------------------*/
1356
1357 /* Ep0 standard request handlers.  These always run in_irq. */
1358
1359 static int standard_setup_req(struct fsg_dev *fsg,
1360                 const struct usb_ctrlrequest *ctrl)
1361 {
1362         struct usb_request      *req = fsg->ep0req;
1363         int                     value = -EOPNOTSUPP;
1364         u16                     w_index = le16_to_cpu(ctrl->wIndex);
1365         u16                     w_value = le16_to_cpu(ctrl->wValue);
1366
1367         /* Usually this just stores reply data in the pre-allocated ep0 buffer,
1368          * but config change events will also reconfigure hardware. */
1369         switch (ctrl->bRequest) {
1370
1371         case USB_REQ_GET_DESCRIPTOR:
1372                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1373                                 USB_RECIP_DEVICE))
1374                         break;
1375                 switch (w_value >> 8) {
1376
1377                 case USB_DT_DEVICE:
1378                         VDBG(fsg, "get device descriptor\n");
1379                         value = sizeof device_desc;
1380                         memcpy(req->buf, &device_desc, value);
1381                         break;
1382                 case USB_DT_DEVICE_QUALIFIER:
1383                         VDBG(fsg, "get device qualifier\n");
1384                         if (!gadget_is_dualspeed(fsg->gadget))
1385                                 break;
1386                         value = sizeof dev_qualifier;
1387                         memcpy(req->buf, &dev_qualifier, value);
1388                         break;
1389
1390                 case USB_DT_OTHER_SPEED_CONFIG:
1391                         VDBG(fsg, "get other-speed config descriptor\n");
1392                         if (!gadget_is_dualspeed(fsg->gadget))
1393                                 break;
1394                         goto get_config;
1395                 case USB_DT_CONFIG:
1396                         VDBG(fsg, "get configuration descriptor\n");
1397 get_config:
1398                         value = populate_config_buf(fsg->gadget,
1399                                         req->buf,
1400                                         w_value >> 8,
1401                                         w_value & 0xff);
1402                         break;
1403
1404                 case USB_DT_STRING:
1405                         VDBG(fsg, "get string descriptor\n");
1406
1407                         /* wIndex == language code */
1408                         value = usb_gadget_get_string(&stringtab,
1409                                         w_value & 0xff, req->buf);
1410                         break;
1411                 }
1412                 break;
1413
1414         /* One config, two speeds */
1415         case USB_REQ_SET_CONFIGURATION:
1416                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
1417                                 USB_RECIP_DEVICE))
1418                         break;
1419                 VDBG(fsg, "set configuration\n");
1420                 if (w_value == CONFIG_VALUE || w_value == 0) {
1421                         fsg->new_config = w_value;
1422
1423                         /* Raise an exception to wipe out previous transaction
1424                          * state (queued bufs, etc) and set the new config. */
1425                         raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
1426                         value = DELAYED_STATUS;
1427                 }
1428                 break;
1429         case USB_REQ_GET_CONFIGURATION:
1430                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1431                                 USB_RECIP_DEVICE))
1432                         break;
1433                 VDBG(fsg, "get configuration\n");
1434                 *(u8 *) req->buf = fsg->config;
1435                 value = 1;
1436                 break;
1437
1438         case USB_REQ_SET_INTERFACE:
1439                 if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD |
1440                                 USB_RECIP_INTERFACE))
1441                         break;
1442                 if (fsg->config && w_index == 0) {
1443
1444                         /* Raise an exception to wipe out previous transaction
1445                          * state (queued bufs, etc) and install the new
1446                          * interface altsetting. */
1447                         raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE);
1448                         value = DELAYED_STATUS;
1449                 }
1450                 break;
1451         case USB_REQ_GET_INTERFACE:
1452                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1453                                 USB_RECIP_INTERFACE))
1454                         break;
1455                 if (!fsg->config)
1456                         break;
1457                 if (w_index != 0) {
1458                         value = -EDOM;
1459                         break;
1460                 }
1461                 VDBG(fsg, "get interface\n");
1462                 *(u8 *) req->buf = 0;
1463                 value = 1;
1464                 break;
1465
1466         default:
1467                 VDBG(fsg,
1468                         "unknown control req %02x.%02x v%04x i%04x l%u\n",
1469                         ctrl->bRequestType, ctrl->bRequest,
1470                         w_value, w_index, le16_to_cpu(ctrl->wLength));
1471         }
1472
1473         return value;
1474 }
1475
1476
1477 static int fsg_setup(struct usb_gadget *gadget,
1478                 const struct usb_ctrlrequest *ctrl)
1479 {
1480         struct fsg_dev          *fsg = get_gadget_data(gadget);
1481         int                     rc;
1482         int                     w_length = le16_to_cpu(ctrl->wLength);
1483
1484         ++fsg->ep0_req_tag;             // Record arrival of a new request
1485         fsg->ep0req->context = NULL;
1486         fsg->ep0req->length = 0;
1487         dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
1488
1489         if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS)
1490                 rc = class_setup_req(fsg, ctrl);
1491         else
1492                 rc = standard_setup_req(fsg, ctrl);
1493
1494         /* Respond with data/status or defer until later? */
1495         if (rc >= 0 && rc != DELAYED_STATUS) {
1496                 rc = min(rc, w_length);
1497                 fsg->ep0req->length = rc;
1498                 fsg->ep0req->zero = rc < w_length;
1499                 fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
1500                                 "ep0-in" : "ep0-out");
1501                 rc = ep0_queue(fsg);
1502         }
1503
1504         /* Device either stalls (rc < 0) or reports success */
1505         return rc;
1506 }
1507
1508
1509 /*-------------------------------------------------------------------------*/
1510
1511 /* All the following routines run in process context */
1512
1513
1514 /* Use this for bulk or interrupt transfers, not ep0 */
1515 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
1516                 struct usb_request *req, int *pbusy,
1517                 enum fsg_buffer_state *state)
1518 {
1519         int     rc;
1520
1521         if (ep == fsg->bulk_in)
1522                 dump_msg(fsg, "bulk-in", req->buf, req->length);
1523         else if (ep == fsg->intr_in)
1524                 dump_msg(fsg, "intr-in", req->buf, req->length);
1525
1526         spin_lock_irq(&fsg->lock);
1527         *pbusy = 1;
1528         *state = BUF_STATE_BUSY;
1529         spin_unlock_irq(&fsg->lock);
1530         rc = usb_ep_queue(ep, req, GFP_KERNEL);
1531         if (rc != 0) {
1532                 *pbusy = 0;
1533                 *state = BUF_STATE_EMPTY;
1534
1535                 /* We can't do much more than wait for a reset */
1536
1537                 /* Note: currently the net2280 driver fails zero-length
1538                  * submissions if DMA is enabled. */
1539                 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
1540                                                 req->length == 0))
1541                         WARNING(fsg, "error in submission: %s --> %d\n",
1542                                         ep->name, rc);
1543         }
1544 }
1545
1546
1547 static int sleep_thread(struct fsg_dev *fsg)
1548 {
1549         int     rc = 0;
1550
1551         /* Wait until a signal arrives or we are woken up */
1552         for (;;) {
1553                 try_to_freeze();
1554                 set_current_state(TASK_INTERRUPTIBLE);
1555                 if (signal_pending(current)) {
1556                         rc = -EINTR;
1557                         break;
1558                 }
1559                 if (fsg->thread_wakeup_needed)
1560                         break;
1561                 schedule();
1562         }
1563         __set_current_state(TASK_RUNNING);
1564         fsg->thread_wakeup_needed = 0;
1565         return rc;
1566 }
1567
1568
1569 /*-------------------------------------------------------------------------*/
1570
1571 static int do_read(struct fsg_dev *fsg)
1572 {
1573         struct lun              *curlun = fsg->curlun;
1574         u32                     lba;
1575         struct fsg_buffhd       *bh;
1576         int                     rc;
1577         u32                     amount_left;
1578         loff_t                  file_offset, file_offset_tmp;
1579         unsigned int            amount;
1580         unsigned int            partial_page;
1581         ssize_t                 nread;
1582
1583         /* Get the starting Logical Block Address and check that it's
1584          * not too big */
1585         if (fsg->cmnd[0] == SC_READ_6)
1586                 lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
1587         else {
1588                 lba = get_be32(&fsg->cmnd[2]);
1589
1590                 /* We allow DPO (Disable Page Out = don't save data in the
1591                  * cache) and FUA (Force Unit Access = don't read from the
1592                  * cache), but we don't implement them. */
1593                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1594                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1595                         return -EINVAL;
1596                 }
1597         }
1598         if (lba >= curlun->num_sectors) {
1599                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1600                 return -EINVAL;
1601         }
1602         file_offset = ((loff_t) lba) << 9;
1603
1604         /* Carry out the file reads */
1605         amount_left = fsg->data_size_from_cmnd;
1606         if (unlikely(amount_left == 0))
1607                 return -EIO;            // No default reply
1608
1609         for (;;) {
1610
1611                 /* Figure out how much we need to read:
1612                  * Try to read the remaining amount.
1613                  * But don't read more than the buffer size.
1614                  * And don't try to read past the end of the file.
1615                  * Finally, if we're not at a page boundary, don't read past
1616                  *      the next page.
1617                  * If this means reading 0 then we were asked to read past
1618                  *      the end of file. */
1619                 amount = min((unsigned int) amount_left, mod_data.buflen);
1620                 amount = min((loff_t) amount,
1621                                 curlun->file_length - file_offset);
1622                 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
1623                 if (partial_page > 0)
1624                         amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
1625                                         partial_page);
1626
1627                 /* Wait for the next buffer to become available */
1628                 bh = fsg->next_buffhd_to_fill;
1629                 while (bh->state != BUF_STATE_EMPTY) {
1630                         rc = sleep_thread(fsg);
1631                         if (rc)
1632                                 return rc;
1633                 }
1634
1635                 /* If we were asked to read past the end of file,
1636                  * end with an empty buffer. */
1637                 if (amount == 0) {
1638                         curlun->sense_data =
1639                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1640                         curlun->sense_data_info = file_offset >> 9;
1641                         curlun->info_valid = 1;
1642                         bh->inreq->length = 0;
1643                         bh->state = BUF_STATE_FULL;
1644                         break;
1645                 }
1646
1647                 /* Perform the read */
1648                 file_offset_tmp = file_offset;
1649                 nread = vfs_read(curlun->filp,
1650                                 (char __user *) bh->buf,
1651                                 amount, &file_offset_tmp);
1652                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1653                                 (unsigned long long) file_offset,
1654                                 (int) nread);
1655                 if (signal_pending(current))
1656                         return -EINTR;
1657
1658                 if (nread < 0) {
1659                         LDBG(curlun, "error in file read: %d\n",
1660                                         (int) nread);
1661                         nread = 0;
1662                 } else if (nread < amount) {
1663                         LDBG(curlun, "partial file read: %d/%u\n",
1664                                         (int) nread, amount);
1665                         nread -= (nread & 511); // Round down to a block
1666                 }
1667                 file_offset  += nread;
1668                 amount_left  -= nread;
1669                 fsg->residue -= nread;
1670                 bh->inreq->length = nread;
1671                 bh->state = BUF_STATE_FULL;
1672
1673                 /* If an error occurred, report it and its position */
1674                 if (nread < amount) {
1675                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1676                         curlun->sense_data_info = file_offset >> 9;
1677                         curlun->info_valid = 1;
1678                         break;
1679                 }
1680
1681                 if (amount_left == 0)
1682                         break;          // No more left to read
1683
1684                 /* Send this buffer and go read some more */
1685                 bh->inreq->zero = 0;
1686                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1687                                 &bh->inreq_busy, &bh->state);
1688                 fsg->next_buffhd_to_fill = bh->next;
1689         }
1690
1691         return -EIO;            // No default reply
1692 }
1693
1694
1695 /*-------------------------------------------------------------------------*/
1696
1697 static int do_write(struct fsg_dev *fsg)
1698 {
1699         struct lun              *curlun = fsg->curlun;
1700         u32                     lba;
1701         struct fsg_buffhd       *bh;
1702         int                     get_some_more;
1703         u32                     amount_left_to_req, amount_left_to_write;
1704         loff_t                  usb_offset, file_offset, file_offset_tmp;
1705         unsigned int            amount;
1706         unsigned int            partial_page;
1707         ssize_t                 nwritten;
1708         int                     rc;
1709
1710         if (curlun->ro) {
1711                 curlun->sense_data = SS_WRITE_PROTECTED;
1712                 return -EINVAL;
1713         }
1714         curlun->filp->f_flags &= ~O_SYNC;       // Default is not to wait
1715
1716         /* Get the starting Logical Block Address and check that it's
1717          * not too big */
1718         if (fsg->cmnd[0] == SC_WRITE_6)
1719                 lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
1720         else {
1721                 lba = get_be32(&fsg->cmnd[2]);
1722
1723                 /* We allow DPO (Disable Page Out = don't save data in the
1724                  * cache) and FUA (Force Unit Access = write directly to the
1725                  * medium).  We don't implement DPO; we implement FUA by
1726                  * performing synchronous output. */
1727                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1728                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1729                         return -EINVAL;
1730                 }
1731                 if (fsg->cmnd[1] & 0x08)        // FUA
1732                         curlun->filp->f_flags |= O_SYNC;
1733         }
1734         if (lba >= curlun->num_sectors) {
1735                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1736                 return -EINVAL;
1737         }
1738
1739         /* Carry out the file writes */
1740         get_some_more = 1;
1741         file_offset = usb_offset = ((loff_t) lba) << 9;
1742         amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd;
1743
1744         while (amount_left_to_write > 0) {
1745
1746                 /* Queue a request for more data from the host */
1747                 bh = fsg->next_buffhd_to_fill;
1748                 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
1749
1750                         /* Figure out how much we want to get:
1751                          * Try to get the remaining amount.
1752                          * But don't get more than the buffer size.
1753                          * And don't try to go past the end of the file.
1754                          * If we're not at a page boundary,
1755                          *      don't go past the next page.
1756                          * If this means getting 0, then we were asked
1757                          *      to write past the end of file.
1758                          * Finally, round down to a block boundary. */
1759                         amount = min(amount_left_to_req, mod_data.buflen);
1760                         amount = min((loff_t) amount, curlun->file_length -
1761                                         usb_offset);
1762                         partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
1763                         if (partial_page > 0)
1764                                 amount = min(amount,
1765         (unsigned int) PAGE_CACHE_SIZE - partial_page);
1766
1767                         if (amount == 0) {
1768                                 get_some_more = 0;
1769                                 curlun->sense_data =
1770                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1771                                 curlun->sense_data_info = usb_offset >> 9;
1772                                 curlun->info_valid = 1;
1773                                 continue;
1774                         }
1775                         amount -= (amount & 511);
1776                         if (amount == 0) {
1777
1778                                 /* Why were we were asked to transfer a
1779                                  * partial block? */
1780                                 get_some_more = 0;
1781                                 continue;
1782                         }
1783
1784                         /* Get the next buffer */
1785                         usb_offset += amount;
1786                         fsg->usb_amount_left -= amount;
1787                         amount_left_to_req -= amount;
1788                         if (amount_left_to_req == 0)
1789                                 get_some_more = 0;
1790
1791                         /* amount is always divisible by 512, hence by
1792                          * the bulk-out maxpacket size */
1793                         bh->outreq->length = bh->bulk_out_intended_length =
1794                                         amount;
1795                         bh->outreq->short_not_ok = 1;
1796                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
1797                                         &bh->outreq_busy, &bh->state);
1798                         fsg->next_buffhd_to_fill = bh->next;
1799                         continue;
1800                 }
1801
1802                 /* Write the received data to the backing file */
1803                 bh = fsg->next_buffhd_to_drain;
1804                 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
1805                         break;                  // We stopped early
1806                 if (bh->state == BUF_STATE_FULL) {
1807                         smp_rmb();
1808                         fsg->next_buffhd_to_drain = bh->next;
1809                         bh->state = BUF_STATE_EMPTY;
1810
1811                         /* Did something go wrong with the transfer? */
1812                         if (bh->outreq->status != 0) {
1813                                 curlun->sense_data = SS_COMMUNICATION_FAILURE;
1814                                 curlun->sense_data_info = file_offset >> 9;
1815                                 curlun->info_valid = 1;
1816                                 break;
1817                         }
1818
1819                         amount = bh->outreq->actual;
1820                         if (curlun->file_length - file_offset < amount) {
1821                                 LERROR(curlun,
1822         "write %u @ %llu beyond end %llu\n",
1823         amount, (unsigned long long) file_offset,
1824         (unsigned long long) curlun->file_length);
1825                                 amount = curlun->file_length - file_offset;
1826                         }
1827
1828                         /* Perform the write */
1829                         file_offset_tmp = file_offset;
1830                         nwritten = vfs_write(curlun->filp,
1831                                         (char __user *) bh->buf,
1832                                         amount, &file_offset_tmp);
1833                         VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1834                                         (unsigned long long) file_offset,
1835                                         (int) nwritten);
1836                         if (signal_pending(current))
1837                                 return -EINTR;          // Interrupted!
1838
1839                         if (nwritten < 0) {
1840                                 LDBG(curlun, "error in file write: %d\n",
1841                                                 (int) nwritten);
1842                                 nwritten = 0;
1843                         } else if (nwritten < amount) {
1844                                 LDBG(curlun, "partial file write: %d/%u\n",
1845                                                 (int) nwritten, amount);
1846                                 nwritten -= (nwritten & 511);
1847                                                 // Round down to a block
1848                         }
1849                         file_offset += nwritten;
1850                         amount_left_to_write -= nwritten;
1851                         fsg->residue -= nwritten;
1852
1853                         /* If an error occurred, report it and its position */
1854                         if (nwritten < amount) {
1855                                 curlun->sense_data = SS_WRITE_ERROR;
1856                                 curlun->sense_data_info = file_offset >> 9;
1857                                 curlun->info_valid = 1;
1858                                 break;
1859                         }
1860
1861                         /* Did the host decide to stop early? */
1862                         if (bh->outreq->actual != bh->outreq->length) {
1863                                 fsg->short_packet_received = 1;
1864                                 break;
1865                         }
1866                         continue;
1867                 }
1868
1869                 /* Wait for something to happen */
1870                 rc = sleep_thread(fsg);
1871                 if (rc)
1872                         return rc;
1873         }
1874
1875         return -EIO;            // No default reply
1876 }
1877
1878
1879 /*-------------------------------------------------------------------------*/
1880
1881 /* Sync the file data, don't bother with the metadata.
1882  * This code was copied from fs/buffer.c:sys_fdatasync(). */
1883 static int fsync_sub(struct lun *curlun)
1884 {
1885         struct file     *filp = curlun->filp;
1886
1887         if (curlun->ro || !filp)
1888                 return 0;
1889         return vfs_fsync(filp, filp->f_path.dentry, 1);
1890 }
1891
1892 static void fsync_all(struct fsg_dev *fsg)
1893 {
1894         int     i;
1895
1896         for (i = 0; i < fsg->nluns; ++i)
1897                 fsync_sub(&fsg->luns[i]);
1898 }
1899
1900 static int do_synchronize_cache(struct fsg_dev *fsg)
1901 {
1902         struct lun      *curlun = fsg->curlun;
1903         int             rc;
1904
1905         /* We ignore the requested LBA and write out all file's
1906          * dirty data buffers. */
1907         rc = fsync_sub(curlun);
1908         if (rc)
1909                 curlun->sense_data = SS_WRITE_ERROR;
1910         return 0;
1911 }
1912
1913
1914 /*-------------------------------------------------------------------------*/
1915
1916 static void invalidate_sub(struct lun *curlun)
1917 {
1918         struct file     *filp = curlun->filp;
1919         struct inode    *inode = filp->f_path.dentry->d_inode;
1920         unsigned long   rc;
1921
1922         rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1923         VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc);
1924 }
1925
1926 static int do_verify(struct fsg_dev *fsg)
1927 {
1928         struct lun              *curlun = fsg->curlun;
1929         u32                     lba;
1930         u32                     verification_length;
1931         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
1932         loff_t                  file_offset, file_offset_tmp;
1933         u32                     amount_left;
1934         unsigned int            amount;
1935         ssize_t                 nread;
1936
1937         /* Get the starting Logical Block Address and check that it's
1938          * not too big */
1939         lba = get_be32(&fsg->cmnd[2]);
1940         if (lba >= curlun->num_sectors) {
1941                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1942                 return -EINVAL;
1943         }
1944
1945         /* We allow DPO (Disable Page Out = don't save data in the
1946          * cache) but we don't implement it. */
1947         if ((fsg->cmnd[1] & ~0x10) != 0) {
1948                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1949                 return -EINVAL;
1950         }
1951
1952         verification_length = get_be16(&fsg->cmnd[7]);
1953         if (unlikely(verification_length == 0))
1954                 return -EIO;            // No default reply
1955
1956         /* Prepare to carry out the file verify */
1957         amount_left = verification_length << 9;
1958         file_offset = ((loff_t) lba) << 9;
1959
1960         /* Write out all the dirty buffers before invalidating them */
1961         fsync_sub(curlun);
1962         if (signal_pending(current))
1963                 return -EINTR;
1964
1965         invalidate_sub(curlun);
1966         if (signal_pending(current))
1967                 return -EINTR;
1968
1969         /* Just try to read the requested blocks */
1970         while (amount_left > 0) {
1971
1972                 /* Figure out how much we need to read:
1973                  * Try to read the remaining amount, but not more than
1974                  * the buffer size.
1975                  * And don't try to read past the end of the file.
1976                  * If this means reading 0 then we were asked to read
1977                  * past the end of file. */
1978                 amount = min((unsigned int) amount_left, mod_data.buflen);
1979                 amount = min((loff_t) amount,
1980                                 curlun->file_length - file_offset);
1981                 if (amount == 0) {
1982                         curlun->sense_data =
1983                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1984                         curlun->sense_data_info = file_offset >> 9;
1985                         curlun->info_valid = 1;
1986                         break;
1987                 }
1988
1989                 /* Perform the read */
1990                 file_offset_tmp = file_offset;
1991                 nread = vfs_read(curlun->filp,
1992                                 (char __user *) bh->buf,
1993                                 amount, &file_offset_tmp);
1994                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1995                                 (unsigned long long) file_offset,
1996                                 (int) nread);
1997                 if (signal_pending(current))
1998                         return -EINTR;
1999
2000                 if (nread < 0) {
2001                         LDBG(curlun, "error in file verify: %d\n",
2002                                         (int) nread);
2003                         nread = 0;
2004                 } else if (nread < amount) {
2005                         LDBG(curlun, "partial file verify: %d/%u\n",
2006                                         (int) nread, amount);
2007                         nread -= (nread & 511); // Round down to a sector
2008                 }
2009                 if (nread == 0) {
2010                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
2011                         curlun->sense_data_info = file_offset >> 9;
2012                         curlun->info_valid = 1;
2013                         break;
2014                 }
2015                 file_offset += nread;
2016                 amount_left -= nread;
2017         }
2018         return 0;
2019 }
2020
2021
2022 /*-------------------------------------------------------------------------*/
2023
2024 static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2025 {
2026         u8      *buf = (u8 *) bh->buf;
2027
2028         static char vendor_id[] = "Linux   ";
2029         static char product_disk_id[] = "File-Stor Gadget";
2030         static char product_cdrom_id[] = "File-CD Gadget  ";
2031
2032         if (!fsg->curlun) {             // Unsupported LUNs are okay
2033                 fsg->bad_lun_okay = 1;
2034                 memset(buf, 0, 36);
2035                 buf[0] = 0x7f;          // Unsupported, no device-type
2036                 buf[4] = 31;            // Additional length
2037                 return 36;
2038         }
2039
2040         memset(buf, 0, 8);
2041         buf[0] = (mod_data.cdrom ? TYPE_CDROM : TYPE_DISK);
2042         if (mod_data.removable)
2043                 buf[1] = 0x80;
2044         buf[2] = 2;             // ANSI SCSI level 2
2045         buf[3] = 2;             // SCSI-2 INQUIRY data format
2046         buf[4] = 31;            // Additional length
2047                                 // No special options
2048         sprintf(buf + 8, "%-8s%-16s%04x", vendor_id,
2049                         (mod_data.cdrom ? product_cdrom_id :
2050                                 product_disk_id),
2051                         mod_data.release);
2052         return 36;
2053 }
2054
2055
2056 static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2057 {
2058         struct lun      *curlun = fsg->curlun;
2059         u8              *buf = (u8 *) bh->buf;
2060         u32             sd, sdinfo;
2061         int             valid;
2062
2063         /*
2064          * From the SCSI-2 spec., section 7.9 (Unit attention condition):
2065          *
2066          * If a REQUEST SENSE command is received from an initiator
2067          * with a pending unit attention condition (before the target
2068          * generates the contingent allegiance condition), then the
2069          * target shall either:
2070          *   a) report any pending sense data and preserve the unit
2071          *      attention condition on the logical unit, or,
2072          *   b) report the unit attention condition, may discard any
2073          *      pending sense data, and clear the unit attention
2074          *      condition on the logical unit for that initiator.
2075          *
2076          * FSG normally uses option a); enable this code to use option b).
2077          */
2078 #if 0
2079         if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
2080                 curlun->sense_data = curlun->unit_attention_data;
2081                 curlun->unit_attention_data = SS_NO_SENSE;
2082         }
2083 #endif
2084
2085         if (!curlun) {          // Unsupported LUNs are okay
2086                 fsg->bad_lun_okay = 1;
2087                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2088                 sdinfo = 0;
2089                 valid = 0;
2090         } else {
2091                 sd = curlun->sense_data;
2092                 sdinfo = curlun->sense_data_info;
2093                 valid = curlun->info_valid << 7;
2094                 curlun->sense_data = SS_NO_SENSE;
2095                 curlun->sense_data_info = 0;
2096                 curlun->info_valid = 0;
2097         }
2098
2099         memset(buf, 0, 18);
2100         buf[0] = valid | 0x70;                  // Valid, current error
2101         buf[2] = SK(sd);
2102         put_be32(&buf[3], sdinfo);              // Sense information
2103         buf[7] = 18 - 8;                        // Additional sense length
2104         buf[12] = ASC(sd);
2105         buf[13] = ASCQ(sd);
2106         return 18;
2107 }
2108
2109
2110 static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2111 {
2112         struct lun      *curlun = fsg->curlun;
2113         u32             lba = get_be32(&fsg->cmnd[2]);
2114         int             pmi = fsg->cmnd[8];
2115         u8              *buf = (u8 *) bh->buf;
2116
2117         /* Check the PMI and LBA fields */
2118         if (pmi > 1 || (pmi == 0 && lba != 0)) {
2119                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2120                 return -EINVAL;
2121         }
2122
2123         put_be32(&buf[0], curlun->num_sectors - 1);     // Max logical block
2124         put_be32(&buf[4], 512);                         // Block length
2125         return 8;
2126 }
2127
2128
2129 static void store_cdrom_address(u8 *dest, int msf, u32 addr)
2130 {
2131         if (msf) {
2132                 /* Convert to Minutes-Seconds-Frames */
2133                 addr >>= 2;             /* Convert to 2048-byte frames */
2134                 addr += 2*75;           /* Lead-in occupies 2 seconds */
2135                 dest[3] = addr % 75;    /* Frames */
2136                 addr /= 75;
2137                 dest[2] = addr % 60;    /* Seconds */
2138                 addr /= 60;
2139                 dest[1] = addr;         /* Minutes */
2140                 dest[0] = 0;            /* Reserved */
2141         } else {
2142                 /* Absolute sector */
2143                 put_be32(dest, addr);
2144         }
2145 }
2146
2147 static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2148 {
2149         struct lun      *curlun = fsg->curlun;
2150         int             msf = fsg->cmnd[1] & 0x02;
2151         u32             lba = get_be32(&fsg->cmnd[2]);
2152         u8              *buf = (u8 *) bh->buf;
2153
2154         if ((fsg->cmnd[1] & ~0x02) != 0) {              /* Mask away MSF */
2155                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2156                 return -EINVAL;
2157         }
2158         if (lba >= curlun->num_sectors) {
2159                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
2160                 return -EINVAL;
2161         }
2162
2163         memset(buf, 0, 8);
2164         buf[0] = 0x01;          /* 2048 bytes of user data, rest is EC */
2165         store_cdrom_address(&buf[4], msf, lba);
2166         return 8;
2167 }
2168
2169
2170 static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2171 {
2172         struct lun      *curlun = fsg->curlun;
2173         int             msf = fsg->cmnd[1] & 0x02;
2174         int             start_track = fsg->cmnd[6];
2175         u8              *buf = (u8 *) bh->buf;
2176
2177         if ((fsg->cmnd[1] & ~0x02) != 0 ||              /* Mask away MSF */
2178                         start_track > 1) {
2179                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2180                 return -EINVAL;
2181         }
2182
2183         memset(buf, 0, 20);
2184         buf[1] = (20-2);                /* TOC data length */
2185         buf[2] = 1;                     /* First track number */
2186         buf[3] = 1;                     /* Last track number */
2187         buf[5] = 0x16;                  /* Data track, copying allowed */
2188         buf[6] = 0x01;                  /* Only track is number 1 */
2189         store_cdrom_address(&buf[8], msf, 0);
2190
2191         buf[13] = 0x16;                 /* Lead-out track is data */
2192         buf[14] = 0xAA;                 /* Lead-out track number */
2193         store_cdrom_address(&buf[16], msf, curlun->num_sectors);
2194         return 20;
2195 }
2196
2197
2198 static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2199 {
2200         struct lun      *curlun = fsg->curlun;
2201         int             mscmnd = fsg->cmnd[0];
2202         u8              *buf = (u8 *) bh->buf;
2203         u8              *buf0 = buf;
2204         int             pc, page_code;
2205         int             changeable_values, all_pages;
2206         int             valid_page = 0;
2207         int             len, limit;
2208
2209         if ((fsg->cmnd[1] & ~0x08) != 0) {              // Mask away DBD
2210                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2211                 return -EINVAL;
2212         }
2213         pc = fsg->cmnd[2] >> 6;
2214         page_code = fsg->cmnd[2] & 0x3f;
2215         if (pc == 3) {
2216                 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
2217                 return -EINVAL;
2218         }
2219         changeable_values = (pc == 1);
2220         all_pages = (page_code == 0x3f);
2221
2222         /* Write the mode parameter header.  Fixed values are: default
2223          * medium type, no cache control (DPOFUA), and no block descriptors.
2224          * The only variable value is the WriteProtect bit.  We will fill in
2225          * the mode data length later. */
2226         memset(buf, 0, 8);
2227         if (mscmnd == SC_MODE_SENSE_6) {
2228                 buf[2] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
2229                 buf += 4;
2230                 limit = 255;
2231         } else {                        // SC_MODE_SENSE_10
2232                 buf[3] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
2233                 buf += 8;
2234                 limit = 65535;          // Should really be mod_data.buflen
2235         }
2236
2237         /* No block descriptors */
2238
2239         /* The mode pages, in numerical order.  The only page we support
2240          * is the Caching page. */
2241         if (page_code == 0x08 || all_pages) {
2242                 valid_page = 1;
2243                 buf[0] = 0x08;          // Page code
2244                 buf[1] = 10;            // Page length
2245                 memset(buf+2, 0, 10);   // None of the fields are changeable
2246
2247                 if (!changeable_values) {
2248                         buf[2] = 0x04;  // Write cache enable,
2249                                         // Read cache not disabled
2250                                         // No cache retention priorities
2251                         put_be16(&buf[4], 0xffff);  // Don't disable prefetch
2252                                         // Minimum prefetch = 0
2253                         put_be16(&buf[8], 0xffff);  // Maximum prefetch
2254                         put_be16(&buf[10], 0xffff); // Maximum prefetch ceiling
2255                 }
2256                 buf += 12;
2257         }
2258
2259         /* Check that a valid page was requested and the mode data length
2260          * isn't too long. */
2261         len = buf - buf0;
2262         if (!valid_page || len > limit) {
2263                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2264                 return -EINVAL;
2265         }
2266
2267         /*  Store the mode data length */
2268         if (mscmnd == SC_MODE_SENSE_6)
2269                 buf0[0] = len - 1;
2270         else
2271                 put_be16(buf0, len - 2);
2272         return len;
2273 }
2274
2275
2276 static int do_start_stop(struct fsg_dev *fsg)
2277 {
2278         struct lun      *curlun = fsg->curlun;
2279         int             loej, start;
2280
2281         if (!mod_data.removable) {
2282                 curlun->sense_data = SS_INVALID_COMMAND;
2283                 return -EINVAL;
2284         }
2285
2286         // int immed = fsg->cmnd[1] & 0x01;
2287         loej = fsg->cmnd[4] & 0x02;
2288         start = fsg->cmnd[4] & 0x01;
2289
2290 #ifdef CONFIG_USB_FILE_STORAGE_TEST
2291         if ((fsg->cmnd[1] & ~0x01) != 0 ||              // Mask away Immed
2292                         (fsg->cmnd[4] & ~0x03) != 0) {  // Mask LoEj, Start
2293                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2294                 return -EINVAL;
2295         }
2296
2297         if (!start) {
2298
2299                 /* Are we allowed to unload the media? */
2300                 if (curlun->prevent_medium_removal) {
2301                         LDBG(curlun, "unload attempt prevented\n");
2302                         curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
2303                         return -EINVAL;
2304                 }
2305                 if (loej) {             // Simulate an unload/eject
2306                         up_read(&fsg->filesem);
2307                         down_write(&fsg->filesem);
2308                         close_backing_file(curlun);
2309                         up_write(&fsg->filesem);
2310                         down_read(&fsg->filesem);
2311                 }
2312         } else {
2313
2314                 /* Our emulation doesn't support mounting; the medium is
2315                  * available for use as soon as it is loaded. */
2316                 if (!backing_file_is_open(curlun)) {
2317                         curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2318                         return -EINVAL;
2319                 }
2320         }
2321 #endif
2322         return 0;
2323 }
2324
2325
2326 static int do_prevent_allow(struct fsg_dev *fsg)
2327 {
2328         struct lun      *curlun = fsg->curlun;
2329         int             prevent;
2330
2331         if (!mod_data.removable) {
2332                 curlun->sense_data = SS_INVALID_COMMAND;
2333                 return -EINVAL;
2334         }
2335
2336         prevent = fsg->cmnd[4] & 0x01;
2337         if ((fsg->cmnd[4] & ~0x01) != 0) {              // Mask away Prevent
2338                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2339                 return -EINVAL;
2340         }
2341
2342         if (curlun->prevent_medium_removal && !prevent)
2343                 fsync_sub(curlun);
2344         curlun->prevent_medium_removal = prevent;
2345         return 0;
2346 }
2347
2348
2349 static int do_read_format_capacities(struct fsg_dev *fsg,
2350                         struct fsg_buffhd *bh)
2351 {
2352         struct lun      *curlun = fsg->curlun;
2353         u8              *buf = (u8 *) bh->buf;
2354
2355         buf[0] = buf[1] = buf[2] = 0;
2356         buf[3] = 8;             // Only the Current/Maximum Capacity Descriptor
2357         buf += 4;
2358
2359         put_be32(&buf[0], curlun->num_sectors);         // Number of blocks
2360         put_be32(&buf[4], 512);                         // Block length
2361         buf[4] = 0x02;                                  // Current capacity
2362         return 12;
2363 }
2364
2365
2366 static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2367 {
2368         struct lun      *curlun = fsg->curlun;
2369
2370         /* We don't support MODE SELECT */
2371         curlun->sense_data = SS_INVALID_COMMAND;
2372         return -EINVAL;
2373 }
2374
2375
2376 /*-------------------------------------------------------------------------*/
2377
2378 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
2379 {
2380         int     rc;
2381
2382         rc = fsg_set_halt(fsg, fsg->bulk_in);
2383         if (rc == -EAGAIN)
2384                 VDBG(fsg, "delayed bulk-in endpoint halt\n");
2385         while (rc != 0) {
2386                 if (rc != -EAGAIN) {
2387                         WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
2388                         rc = 0;
2389                         break;
2390                 }
2391
2392                 /* Wait for a short time and then try again */
2393                 if (msleep_interruptible(100) != 0)
2394                         return -EINTR;
2395                 rc = usb_ep_set_halt(fsg->bulk_in);
2396         }
2397         return rc;
2398 }
2399
2400 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
2401 {
2402         int     rc;
2403
2404         DBG(fsg, "bulk-in set wedge\n");
2405         rc = usb_ep_set_wedge(fsg->bulk_in);
2406         if (rc == -EAGAIN)
2407                 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
2408         while (rc != 0) {
2409                 if (rc != -EAGAIN) {
2410                         WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
2411                         rc = 0;
2412                         break;
2413                 }
2414
2415                 /* Wait for a short time and then try again */
2416                 if (msleep_interruptible(100) != 0)
2417                         return -EINTR;
2418                 rc = usb_ep_set_wedge(fsg->bulk_in);
2419         }
2420         return rc;
2421 }
2422
2423 static int pad_with_zeros(struct fsg_dev *fsg)
2424 {
2425         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
2426         u32                     nkeep = bh->inreq->length;
2427         u32                     nsend;
2428         int                     rc;
2429
2430         bh->state = BUF_STATE_EMPTY;            // For the first iteration
2431         fsg->usb_amount_left = nkeep + fsg->residue;
2432         while (fsg->usb_amount_left > 0) {
2433
2434                 /* Wait for the next buffer to be free */
2435                 while (bh->state != BUF_STATE_EMPTY) {
2436                         rc = sleep_thread(fsg);
2437                         if (rc)
2438                                 return rc;
2439                 }
2440
2441                 nsend = min(fsg->usb_amount_left, (u32) mod_data.buflen);
2442                 memset(bh->buf + nkeep, 0, nsend - nkeep);
2443                 bh->inreq->length = nsend;
2444                 bh->inreq->zero = 0;
2445                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2446                                 &bh->inreq_busy, &bh->state);
2447                 bh = fsg->next_buffhd_to_fill = bh->next;
2448                 fsg->usb_amount_left -= nsend;
2449                 nkeep = 0;
2450         }
2451         return 0;
2452 }
2453
2454 static int throw_away_data(struct fsg_dev *fsg)
2455 {
2456         struct fsg_buffhd       *bh;
2457         u32                     amount;
2458         int                     rc;
2459
2460         while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY ||
2461                         fsg->usb_amount_left > 0) {
2462
2463                 /* Throw away the data in a filled buffer */
2464                 if (bh->state == BUF_STATE_FULL) {
2465                         smp_rmb();
2466                         bh->state = BUF_STATE_EMPTY;
2467                         fsg->next_buffhd_to_drain = bh->next;
2468
2469                         /* A short packet or an error ends everything */
2470                         if (bh->outreq->actual != bh->outreq->length ||
2471                                         bh->outreq->status != 0) {
2472                                 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2473                                 return -EINTR;
2474                         }
2475                         continue;
2476                 }
2477
2478                 /* Try to submit another request if we need one */
2479                 bh = fsg->next_buffhd_to_fill;
2480                 if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
2481                         amount = min(fsg->usb_amount_left,
2482                                         (u32) mod_data.buflen);
2483
2484                         /* amount is always divisible by 512, hence by
2485                          * the bulk-out maxpacket size */
2486                         bh->outreq->length = bh->bulk_out_intended_length =
2487                                         amount;
2488                         bh->outreq->short_not_ok = 1;
2489                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
2490                                         &bh->outreq_busy, &bh->state);
2491                         fsg->next_buffhd_to_fill = bh->next;
2492                         fsg->usb_amount_left -= amount;
2493                         continue;
2494                 }
2495
2496                 /* Otherwise wait for something to happen */
2497                 rc = sleep_thread(fsg);
2498                 if (rc)
2499                         return rc;
2500         }
2501         return 0;
2502 }
2503
2504
2505 static int finish_reply(struct fsg_dev *fsg)
2506 {
2507         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
2508         int                     rc = 0;
2509
2510         switch (fsg->data_dir) {
2511         case DATA_DIR_NONE:
2512                 break;                  // Nothing to send
2513
2514         /* If we don't know whether the host wants to read or write,
2515          * this must be CB or CBI with an unknown command.  We mustn't
2516          * try to send or receive any data.  So stall both bulk pipes
2517          * if we can and wait for a reset. */
2518         case DATA_DIR_UNKNOWN:
2519                 if (mod_data.can_stall) {
2520                         fsg_set_halt(fsg, fsg->bulk_out);
2521                         rc = halt_bulk_in_endpoint(fsg);
2522                 }
2523                 break;
2524
2525         /* All but the last buffer of data must have already been sent */
2526         case DATA_DIR_TO_HOST:
2527                 if (fsg->data_size == 0)
2528                         ;               // Nothing to send
2529
2530                 /* If there's no residue, simply send the last buffer */
2531                 else if (fsg->residue == 0) {
2532                         bh->inreq->zero = 0;
2533                         start_transfer(fsg, fsg->bulk_in, bh->inreq,
2534                                         &bh->inreq_busy, &bh->state);
2535                         fsg->next_buffhd_to_fill = bh->next;
2536                 }
2537
2538                 /* There is a residue.  For CB and CBI, simply mark the end
2539                  * of the data with a short packet.  However, if we are
2540                  * allowed to stall, there was no data at all (residue ==
2541                  * data_size), and the command failed (invalid LUN or
2542                  * sense data is set), then halt the bulk-in endpoint
2543                  * instead. */
2544                 else if (!transport_is_bbb()) {
2545                         if (mod_data.can_stall &&
2546                                         fsg->residue == fsg->data_size &&
2547         (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) {
2548                                 bh->state = BUF_STATE_EMPTY;
2549                                 rc = halt_bulk_in_endpoint(fsg);
2550                         } else {
2551                                 bh->inreq->zero = 1;
2552                                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2553                                                 &bh->inreq_busy, &bh->state);
2554                                 fsg->next_buffhd_to_fill = bh->next;
2555                         }
2556                 }
2557
2558                 /* For Bulk-only, if we're allowed to stall then send the
2559                  * short packet and halt the bulk-in endpoint.  If we can't
2560                  * stall, pad out the remaining data with 0's. */
2561                 else {
2562                         if (mod_data.can_stall) {
2563                                 bh->inreq->zero = 1;
2564                                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2565                                                 &bh->inreq_busy, &bh->state);
2566                                 fsg->next_buffhd_to_fill = bh->next;
2567                                 rc = halt_bulk_in_endpoint(fsg);
2568                         } else
2569                                 rc = pad_with_zeros(fsg);
2570                 }
2571                 break;
2572
2573         /* We have processed all we want from the data the host has sent.
2574          * There may still be outstanding bulk-out requests. */
2575         case DATA_DIR_FROM_HOST:
2576                 if (fsg->residue == 0)
2577                         ;               // Nothing to receive
2578
2579                 /* Did the host stop sending unexpectedly early? */
2580                 else if (fsg->short_packet_received) {
2581                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2582                         rc = -EINTR;
2583                 }
2584
2585                 /* We haven't processed all the incoming data.  Even though
2586                  * we may be allowed to stall, doing so would cause a race.
2587                  * The controller may already have ACK'ed all the remaining
2588                  * bulk-out packets, in which case the host wouldn't see a
2589                  * STALL.  Not realizing the endpoint was halted, it wouldn't
2590                  * clear the halt -- leading to problems later on. */
2591 #if 0
2592                 else if (mod_data.can_stall) {
2593                         fsg_set_halt(fsg, fsg->bulk_out);
2594                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2595                         rc = -EINTR;
2596                 }
2597 #endif
2598
2599                 /* We can't stall.  Read in the excess data and throw it
2600                  * all away. */
2601                 else
2602                         rc = throw_away_data(fsg);
2603                 break;
2604         }
2605         return rc;
2606 }
2607
2608
2609 static int send_status(struct fsg_dev *fsg)
2610 {
2611         struct lun              *curlun = fsg->curlun;
2612         struct fsg_buffhd       *bh;
2613         int                     rc;
2614         u8                      status = USB_STATUS_PASS;
2615         u32                     sd, sdinfo = 0;
2616
2617         /* Wait for the next buffer to become available */
2618         bh = fsg->next_buffhd_to_fill;
2619         while (bh->state != BUF_STATE_EMPTY) {
2620                 rc = sleep_thread(fsg);
2621                 if (rc)
2622                         return rc;
2623         }
2624
2625         if (curlun) {
2626                 sd = curlun->sense_data;
2627                 sdinfo = curlun->sense_data_info;
2628         } else if (fsg->bad_lun_okay)
2629                 sd = SS_NO_SENSE;
2630         else
2631                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2632
2633         if (fsg->phase_error) {
2634                 DBG(fsg, "sending phase-error status\n");
2635                 status = USB_STATUS_PHASE_ERROR;
2636                 sd = SS_INVALID_COMMAND;
2637         } else if (sd != SS_NO_SENSE) {
2638                 DBG(fsg, "sending command-failure status\n");
2639                 status = USB_STATUS_FAIL;
2640                 VDBG(fsg, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
2641                                 "  info x%x\n",
2642                                 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
2643         }
2644
2645         if (transport_is_bbb()) {
2646                 struct bulk_cs_wrap     *csw = bh->buf;
2647
2648                 /* Store and send the Bulk-only CSW */
2649                 csw->Signature = __constant_cpu_to_le32(USB_BULK_CS_SIG);
2650                 csw->Tag = fsg->tag;
2651                 csw->Residue = cpu_to_le32(fsg->residue);
2652                 csw->Status = status;
2653
2654                 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
2655                 bh->inreq->zero = 0;
2656                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2657                                 &bh->inreq_busy, &bh->state);
2658
2659         } else if (mod_data.transport_type == USB_PR_CB) {
2660
2661                 /* Control-Bulk transport has no status phase! */
2662                 return 0;
2663
2664         } else {                        // USB_PR_CBI
2665                 struct interrupt_data   *buf = bh->buf;
2666
2667                 /* Store and send the Interrupt data.  UFI sends the ASC
2668                  * and ASCQ bytes.  Everything else sends a Type (which
2669                  * is always 0) and the status Value. */
2670                 if (mod_data.protocol_type == USB_SC_UFI) {
2671                         buf->bType = ASC(sd);
2672                         buf->bValue = ASCQ(sd);
2673                 } else {
2674                         buf->bType = 0;
2675                         buf->bValue = status;
2676                 }
2677                 fsg->intreq->length = CBI_INTERRUPT_DATA_LEN;
2678
2679                 fsg->intr_buffhd = bh;          // Point to the right buffhd
2680                 fsg->intreq->buf = bh->inreq->buf;
2681                 fsg->intreq->context = bh;
2682                 start_transfer(fsg, fsg->intr_in, fsg->intreq,
2683                                 &fsg->intreq_busy, &bh->state);
2684         }
2685
2686         fsg->next_buffhd_to_fill = bh->next;
2687         return 0;
2688 }
2689
2690
2691 /*-------------------------------------------------------------------------*/
2692
2693 /* Check whether the command is properly formed and whether its data size
2694  * and direction agree with the values we already have. */
2695 static int check_command(struct fsg_dev *fsg, int cmnd_size,
2696                 enum data_direction data_dir, unsigned int mask,
2697                 int needs_medium, const char *name)
2698 {
2699         int                     i;
2700         int                     lun = fsg->cmnd[1] >> 5;
2701         static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
2702         char                    hdlen[20];
2703         struct lun              *curlun;
2704
2705         /* Adjust the expected cmnd_size for protocol encapsulation padding.
2706          * Transparent SCSI doesn't pad. */
2707         if (protocol_is_scsi())
2708                 ;
2709
2710         /* There's some disagreement as to whether RBC pads commands or not.
2711          * We'll play it safe and accept either form. */
2712         else if (mod_data.protocol_type == USB_SC_RBC) {
2713                 if (fsg->cmnd_size == 12)
2714                         cmnd_size = 12;
2715
2716         /* All the other protocols pad to 12 bytes */
2717         } else
2718                 cmnd_size = 12;
2719
2720         hdlen[0] = 0;
2721         if (fsg->data_dir != DATA_DIR_UNKNOWN)
2722                 sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
2723                                 fsg->data_size);
2724         VDBG(fsg, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
2725                         name, cmnd_size, dirletter[(int) data_dir],
2726                         fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen);
2727
2728         /* We can't reply at all until we know the correct data direction
2729          * and size. */
2730         if (fsg->data_size_from_cmnd == 0)
2731                 data_dir = DATA_DIR_NONE;
2732         if (fsg->data_dir == DATA_DIR_UNKNOWN) {        // CB or CBI
2733                 fsg->data_dir = data_dir;
2734                 fsg->data_size = fsg->data_size_from_cmnd;
2735
2736         } else {                                        // Bulk-only
2737                 if (fsg->data_size < fsg->data_size_from_cmnd) {
2738
2739                         /* Host data size < Device data size is a phase error.
2740                          * Carry out the command, but only transfer as much
2741                          * as we are allowed. */
2742                         fsg->data_size_from_cmnd = fsg->data_size;
2743                         fsg->phase_error = 1;
2744                 }
2745         }
2746         fsg->residue = fsg->usb_amount_left = fsg->data_size;
2747
2748         /* Conflicting data directions is a phase error */
2749         if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
2750                 fsg->phase_error = 1;
2751                 return -EINVAL;
2752         }
2753
2754         /* Verify the length of the command itself */
2755         if (cmnd_size != fsg->cmnd_size) {
2756
2757                 /* Special case workaround: There are plenty of buggy SCSI
2758                  * implementations. Many have issues with cbw->Length
2759                  * field passing a wrong command size. For those cases we
2760                  * always try to work around the problem by using the length
2761                  * sent by the host side provided it is at least as large
2762                  * as the correct command length.
2763                  * Examples of such cases would be MS-Windows, which issues
2764                  * REQUEST SENSE with cbw->Length == 12 where it should
2765                  * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
2766                  * REQUEST SENSE with cbw->Length == 10 where it should
2767                  * be 6 as well.
2768                  */
2769                 if (cmnd_size <= fsg->cmnd_size) {
2770                         DBG(fsg, "%s is buggy! Expected length %d "
2771                                         "but we got %d\n", name,
2772                                         cmnd_size, fsg->cmnd_size);
2773                         cmnd_size = fsg->cmnd_size;
2774                 } else {
2775                         fsg->phase_error = 1;
2776                         return -EINVAL;
2777                 }
2778         }
2779
2780         /* Check that the LUN values are consistent */
2781         if (transport_is_bbb()) {
2782                 if (fsg->lun != lun)
2783                         DBG(fsg, "using LUN %d from CBW, "
2784                                         "not LUN %d from CDB\n",
2785                                         fsg->lun, lun);
2786         } else
2787                 fsg->lun = lun;         // Use LUN from the command
2788
2789         /* Check the LUN */
2790         if (fsg->lun >= 0 && fsg->lun < fsg->nluns) {
2791                 fsg->curlun = curlun = &fsg->luns[fsg->lun];
2792                 if (fsg->cmnd[0] != SC_REQUEST_SENSE) {
2793                         curlun->sense_data = SS_NO_SENSE;
2794                         curlun->sense_data_info = 0;
2795                         curlun->info_valid = 0;
2796                 }
2797         } else {
2798                 fsg->curlun = curlun = NULL;
2799                 fsg->bad_lun_okay = 0;
2800
2801                 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
2802                  * to use unsupported LUNs; all others may not. */
2803                 if (fsg->cmnd[0] != SC_INQUIRY &&
2804                                 fsg->cmnd[0] != SC_REQUEST_SENSE) {
2805                         DBG(fsg, "unsupported LUN %d\n", fsg->lun);
2806                         return -EINVAL;
2807                 }
2808         }
2809
2810         /* If a unit attention condition exists, only INQUIRY and
2811          * REQUEST SENSE commands are allowed; anything else must fail. */
2812         if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
2813                         fsg->cmnd[0] != SC_INQUIRY &&
2814                         fsg->cmnd[0] != SC_REQUEST_SENSE) {
2815                 curlun->sense_data = curlun->unit_attention_data;
2816                 curlun->unit_attention_data = SS_NO_SENSE;
2817                 return -EINVAL;
2818         }
2819
2820         /* Check that only command bytes listed in the mask are non-zero */
2821         fsg->cmnd[1] &= 0x1f;                   // Mask away the LUN
2822         for (i = 1; i < cmnd_size; ++i) {
2823                 if (fsg->cmnd[i] && !(mask & (1 << i))) {
2824                         if (curlun)
2825                                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2826                         return -EINVAL;
2827                 }
2828         }
2829
2830         /* If the medium isn't mounted and the command needs to access
2831          * it, return an error. */
2832         if (curlun && !backing_file_is_open(curlun) && needs_medium) {
2833                 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2834                 return -EINVAL;
2835         }
2836
2837         return 0;
2838 }
2839
2840
2841 static int do_scsi_command(struct fsg_dev *fsg)
2842 {
2843         struct fsg_buffhd       *bh;
2844         int                     rc;
2845         int                     reply = -EINVAL;
2846         int                     i;
2847         static char             unknown[16];
2848
2849         dump_cdb(fsg);
2850
2851         /* Wait for the next buffer to become available for data or status */
2852         bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill;
2853         while (bh->state != BUF_STATE_EMPTY) {
2854                 rc = sleep_thread(fsg);
2855                 if (rc)
2856                         return rc;
2857         }
2858         fsg->phase_error = 0;
2859         fsg->short_packet_received = 0;
2860
2861         down_read(&fsg->filesem);       // We're using the backing file
2862         switch (fsg->cmnd[0]) {
2863
2864         case SC_INQUIRY:
2865                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2866                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2867                                 (1<<4), 0,
2868                                 "INQUIRY")) == 0)
2869                         reply = do_inquiry(fsg, bh);
2870                 break;
2871
2872         case SC_MODE_SELECT_6:
2873                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2874                 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2875                                 (1<<1) | (1<<4), 0,
2876                                 "MODE SELECT(6)")) == 0)
2877                         reply = do_mode_select(fsg, bh);
2878                 break;
2879
2880         case SC_MODE_SELECT_10:
2881                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2882                 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2883                                 (1<<1) | (3<<7), 0,
2884                                 "MODE SELECT(10)")) == 0)
2885                         reply = do_mode_select(fsg, bh);
2886                 break;
2887
2888         case SC_MODE_SENSE_6:
2889                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2890                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2891                                 (1<<1) | (1<<2) | (1<<4), 0,
2892                                 "MODE SENSE(6)")) == 0)
2893                         reply = do_mode_sense(fsg, bh);
2894                 break;
2895
2896         case SC_MODE_SENSE_10:
2897                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2898                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2899                                 (1<<1) | (1<<2) | (3<<7), 0,
2900                                 "MODE SENSE(10)")) == 0)
2901                         reply = do_mode_sense(fsg, bh);
2902                 break;
2903
2904         case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
2905                 fsg->data_size_from_cmnd = 0;
2906                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2907                                 (1<<4), 0,
2908                                 "PREVENT-ALLOW MEDIUM REMOVAL")) == 0)
2909                         reply = do_prevent_allow(fsg);
2910                 break;
2911
2912         case SC_READ_6:
2913                 i = fsg->cmnd[4];
2914                 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2915                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2916                                 (7<<1) | (1<<4), 1,
2917                                 "READ(6)")) == 0)
2918                         reply = do_read(fsg);
2919                 break;
2920
2921         case SC_READ_10:
2922                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
2923                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2924                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2925                                 "READ(10)")) == 0)
2926                         reply = do_read(fsg);
2927                 break;
2928
2929         case SC_READ_12:
2930                 fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
2931                 if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
2932                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2933                                 "READ(12)")) == 0)
2934                         reply = do_read(fsg);
2935                 break;
2936
2937         case SC_READ_CAPACITY:
2938                 fsg->data_size_from_cmnd = 8;
2939                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2940                                 (0xf<<2) | (1<<8), 1,
2941                                 "READ CAPACITY")) == 0)
2942                         reply = do_read_capacity(fsg, bh);
2943                 break;
2944
2945         case SC_READ_HEADER:
2946                 if (!mod_data.cdrom)
2947                         goto unknown_cmnd;
2948                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2949                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2950                                 (3<<7) | (0x1f<<1), 1,
2951                                 "READ HEADER")) == 0)
2952                         reply = do_read_header(fsg, bh);
2953                 break;
2954
2955         case SC_READ_TOC:
2956                 if (!mod_data.cdrom)
2957                         goto unknown_cmnd;
2958                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2959                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2960                                 (7<<6) | (1<<1), 1,
2961                                 "READ TOC")) == 0)
2962                         reply = do_read_toc(fsg, bh);
2963                 break;
2964
2965         case SC_READ_FORMAT_CAPACITIES:
2966                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2967                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2968                                 (3<<7), 1,
2969                                 "READ FORMAT CAPACITIES")) == 0)
2970                         reply = do_read_format_capacities(fsg, bh);
2971                 break;
2972
2973         case SC_REQUEST_SENSE:
2974                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2975                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2976                                 (1<<4), 0,
2977                                 "REQUEST SENSE")) == 0)
2978                         reply = do_request_sense(fsg, bh);
2979                 break;
2980
2981         case SC_START_STOP_UNIT:
2982                 fsg->data_size_from_cmnd = 0;
2983                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2984                                 (1<<1) | (1<<4), 0,
2985                                 "START-STOP UNIT")) == 0)
2986                         reply = do_start_stop(fsg);
2987                 break;
2988
2989         case SC_SYNCHRONIZE_CACHE:
2990                 fsg->data_size_from_cmnd = 0;
2991                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2992                                 (0xf<<2) | (3<<7), 1,
2993                                 "SYNCHRONIZE CACHE")) == 0)
2994                         reply = do_synchronize_cache(fsg);
2995                 break;
2996
2997         case SC_TEST_UNIT_READY:
2998                 fsg->data_size_from_cmnd = 0;
2999                 reply = check_command(fsg, 6, DATA_DIR_NONE,
3000                                 0, 1,
3001                                 "TEST UNIT READY");
3002                 break;
3003
3004         /* Although optional, this command is used by MS-Windows.  We
3005          * support a minimal version: BytChk must be 0. */
3006         case SC_VERIFY:
3007                 fsg->data_size_from_cmnd = 0;
3008                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
3009                                 (1<<1) | (0xf<<2) | (3<<7), 1,
3010                                 "VERIFY")) == 0)
3011                         reply = do_verify(fsg);
3012                 break;
3013
3014         case SC_WRITE_6:
3015                 i = fsg->cmnd[4];
3016                 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
3017                 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
3018                                 (7<<1) | (1<<4), 1,
3019                                 "WRITE(6)")) == 0)
3020                         reply = do_write(fsg);
3021                 break;
3022
3023         case SC_WRITE_10:
3024                 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
3025                 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
3026                                 (1<<1) | (0xf<<2) | (3<<7), 1,
3027                                 "WRITE(10)")) == 0)
3028                         reply = do_write(fsg);
3029                 break;
3030
3031         case SC_WRITE_12:
3032                 fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
3033                 if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
3034                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
3035                                 "WRITE(12)")) == 0)
3036                         reply = do_write(fsg);
3037                 break;
3038
3039         /* Some mandatory commands that we recognize but don't implement.
3040          * They don't mean much in this setting.  It's left as an exercise
3041          * for anyone interested to implement RESERVE and RELEASE in terms
3042          * of Posix locks. */
3043         case SC_FORMAT_UNIT:
3044         case SC_RELEASE:
3045         case SC_RESERVE:
3046         case SC_SEND_DIAGNOSTIC:
3047                 // Fall through
3048
3049         default:
3050  unknown_cmnd:
3051                 fsg->data_size_from_cmnd = 0;
3052                 sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]);
3053                 if ((reply = check_command(fsg, fsg->cmnd_size,
3054                                 DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) {
3055                         fsg->curlun->sense_data = SS_INVALID_COMMAND;
3056                         reply = -EINVAL;
3057                 }
3058                 break;
3059         }
3060         up_read(&fsg->filesem);
3061
3062         if (reply == -EINTR || signal_pending(current))
3063                 return -EINTR;
3064
3065         /* Set up the single reply buffer for finish_reply() */
3066         if (reply == -EINVAL)
3067                 reply = 0;              // Error reply length
3068         if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
3069                 reply = min((u32) reply, fsg->data_size_from_cmnd);
3070                 bh->inreq->length = reply;
3071                 bh->state = BUF_STATE_FULL;
3072                 fsg->residue -= reply;
3073         }                               // Otherwise it's already set
3074
3075         return 0;
3076 }
3077
3078
3079 /*-------------------------------------------------------------------------*/
3080
3081 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
3082 {
3083         struct usb_request      *req = bh->outreq;
3084         struct bulk_cb_wrap     *cbw = req->buf;
3085
3086         /* Was this a real packet?  Should it be ignored? */
3087         if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
3088                 return -EINVAL;
3089
3090         /* Is the CBW valid? */
3091         if (req->actual != USB_BULK_CB_WRAP_LEN ||
3092                         cbw->Signature != __constant_cpu_to_le32(
3093                                 USB_BULK_CB_SIG)) {
3094                 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
3095                                 req->actual,
3096                                 le32_to_cpu(cbw->Signature));
3097
3098                 /* The Bulk-only spec says we MUST stall the IN endpoint
3099                  * (6.6.1), so it's unavoidable.  It also says we must
3100                  * retain this state until the next reset, but there's
3101                  * no way to tell the controller driver it should ignore
3102                  * Clear-Feature(HALT) requests.
3103                  *
3104                  * We aren't required to halt the OUT endpoint; instead
3105                  * we can simply accept and discard any data received
3106                  * until the next reset. */
3107                 wedge_bulk_in_endpoint(fsg);
3108                 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
3109                 return -EINVAL;
3110         }
3111
3112         /* Is the CBW meaningful? */
3113         if (cbw->Lun >= MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
3114                         cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
3115                 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
3116                                 "cmdlen %u\n",
3117                                 cbw->Lun, cbw->Flags, cbw->Length);
3118
3119                 /* We can do anything we want here, so let's stall the
3120                  * bulk pipes if we are allowed to. */
3121                 if (mod_data.can_stall) {
3122                         fsg_set_halt(fsg, fsg->bulk_out);
3123                         halt_bulk_in_endpoint(fsg);
3124                 }
3125                 return -EINVAL;
3126         }
3127
3128         /* Save the command for later */
3129         fsg->cmnd_size = cbw->Length;
3130         memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size);
3131         if (cbw->Flags & USB_BULK_IN_FLAG)
3132                 fsg->data_dir = DATA_DIR_TO_HOST;
3133         else
3134                 fsg->data_dir = DATA_DIR_FROM_HOST;
3135         fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
3136         if (fsg->data_size == 0)
3137                 fsg->data_dir = DATA_DIR_NONE;
3138         fsg->lun = cbw->Lun;
3139         fsg->tag = cbw->Tag;
3140         return 0;
3141 }
3142
3143
3144 static int get_next_command(struct fsg_dev *fsg)
3145 {
3146         struct fsg_buffhd       *bh;
3147         int                     rc = 0;
3148
3149         if (transport_is_bbb()) {
3150
3151                 /* Wait for the next buffer to become available */
3152                 bh = fsg->next_buffhd_to_fill;
3153                 while (bh->state != BUF_STATE_EMPTY) {
3154                         rc = sleep_thread(fsg);
3155                         if (rc)
3156                                 return rc;
3157                 }
3158
3159                 /* Queue a request to read a Bulk-only CBW */
3160                 set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
3161                 bh->outreq->short_not_ok = 1;
3162                 start_transfer(fsg, fsg->bulk_out, bh->outreq,
3163                                 &bh->outreq_busy, &bh->state);
3164
3165                 /* We will drain the buffer in software, which means we
3166                  * can reuse it for the next filling.  No need to advance
3167                  * next_buffhd_to_fill. */
3168
3169                 /* Wait for the CBW to arrive */
3170                 while (bh->state != BUF_STATE_FULL) {
3171                         rc = sleep_thread(fsg);
3172                         if (rc)
3173                                 return rc;
3174                 }
3175                 smp_rmb();
3176                 rc = received_cbw(fsg, bh);
3177                 bh->state = BUF_STATE_EMPTY;
3178
3179         } else {                // USB_PR_CB or USB_PR_CBI
3180
3181                 /* Wait for the next command to arrive */
3182                 while (fsg->cbbuf_cmnd_size == 0) {
3183                         rc = sleep_thread(fsg);
3184                         if (rc)
3185                                 return rc;
3186                 }
3187
3188                 /* Is the previous status interrupt request still busy?
3189                  * The host is allowed to skip reading the status,
3190                  * so we must cancel it. */
3191                 if (fsg->intreq_busy)
3192                         usb_ep_dequeue(fsg->intr_in, fsg->intreq);
3193
3194                 /* Copy the command and mark the buffer empty */
3195                 fsg->data_dir = DATA_DIR_UNKNOWN;
3196                 spin_lock_irq(&fsg->lock);
3197                 fsg->cmnd_size = fsg->cbbuf_cmnd_size;
3198                 memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size);
3199                 fsg->cbbuf_cmnd_size = 0;
3200                 spin_unlock_irq(&fsg->lock);
3201         }
3202         return rc;
3203 }
3204
3205
3206 /*-------------------------------------------------------------------------*/
3207
3208 static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
3209                 const struct usb_endpoint_descriptor *d)
3210 {
3211         int     rc;
3212
3213         ep->driver_data = fsg;
3214         rc = usb_ep_enable(ep, d);
3215         if (rc)
3216                 ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
3217         return rc;
3218 }
3219
3220 static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
3221                 struct usb_request **preq)
3222 {
3223         *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
3224         if (*preq)
3225                 return 0;
3226         ERROR(fsg, "can't allocate request for %s\n", ep->name);
3227         return -ENOMEM;
3228 }
3229
3230 /*
3231  * Reset interface setting and re-init endpoint state (toggle etc).
3232  * Call with altsetting < 0 to disable the interface.  The only other
3233  * available altsetting is 0, which enables the interface.
3234  */
3235 static int do_set_interface(struct fsg_dev *fsg, int altsetting)
3236 {
3237         int     rc = 0;
3238         int     i;
3239         const struct usb_endpoint_descriptor    *d;
3240
3241         if (fsg->running)
3242                 DBG(fsg, "reset interface\n");
3243
3244 reset:
3245         /* Deallocate the requests */
3246         for (i = 0; i < NUM_BUFFERS; ++i) {
3247                 struct fsg_buffhd *bh = &fsg->buffhds[i];
3248
3249                 if (bh->inreq) {
3250                         usb_ep_free_request(fsg->bulk_in, bh->inreq);
3251                         bh->inreq = NULL;
3252                 }
3253                 if (bh->outreq) {
3254                         usb_ep_free_request(fsg->bulk_out, bh->outreq);
3255                         bh->outreq = NULL;
3256                 }
3257         }
3258         if (fsg->intreq) {
3259                 usb_ep_free_request(fsg->intr_in, fsg->intreq);
3260                 fsg->intreq = NULL;
3261         }
3262
3263         /* Disable the endpoints */
3264         if (fsg->bulk_in_enabled) {
3265                 usb_ep_disable(fsg->bulk_in);
3266                 fsg->bulk_in_enabled = 0;
3267         }
3268         if (fsg->bulk_out_enabled) {
3269                 usb_ep_disable(fsg->bulk_out);
3270                 fsg->bulk_out_enabled = 0;
3271         }
3272         if (fsg->intr_in_enabled) {
3273                 usb_ep_disable(fsg->intr_in);
3274                 fsg->intr_in_enabled = 0;
3275         }
3276
3277         fsg->running = 0;
3278         if (altsetting < 0 || rc != 0)
3279                 return rc;
3280
3281         DBG(fsg, "set interface %d\n", altsetting);
3282
3283         /* Enable the endpoints */
3284         d = ep_desc(fsg->gadget, &fs_bulk_in_desc, &hs_bulk_in_desc);
3285         if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
3286                 goto reset;
3287         fsg->bulk_in_enabled = 1;
3288
3289         d = ep_desc(fsg->gadget, &fs_bulk_out_desc, &hs_bulk_out_desc);
3290         if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0)
3291                 goto reset;
3292         fsg->bulk_out_enabled = 1;
3293         fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
3294         clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
3295
3296         if (transport_is_cbi()) {
3297                 d = ep_desc(fsg->gadget, &fs_intr_in_desc, &hs_intr_in_desc);
3298                 if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0)
3299                         goto reset;
3300                 fsg->intr_in_enabled = 1;
3301         }
3302
3303         /* Allocate the requests */
3304         for (i = 0; i < NUM_BUFFERS; ++i) {
3305                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
3306
3307                 if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0)
3308                         goto reset;
3309                 if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0)
3310                         goto reset;
3311                 bh->inreq->buf = bh->outreq->buf = bh->buf;
3312                 bh->inreq->context = bh->outreq->context = bh;
3313                 bh->inreq->complete = bulk_in_complete;
3314                 bh->outreq->complete = bulk_out_complete;
3315         }
3316         if (transport_is_cbi()) {
3317                 if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0)
3318                         goto reset;
3319                 fsg->intreq->complete = intr_in_complete;
3320         }
3321
3322         fsg->running = 1;
3323         for (i = 0; i < fsg->nluns; ++i)
3324                 fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3325         return rc;
3326 }
3327
3328
3329 /*
3330  * Change our operational configuration.  This code must agree with the code
3331  * that returns config descriptors, and with interface altsetting code.
3332  *
3333  * It's also responsible for power management interactions.  Some
3334  * configurations might not work with our current power sources.
3335  * For now we just assume the gadget is always self-powered.
3336  */
3337 static int do_set_config(struct fsg_dev *fsg, u8 new_config)
3338 {
3339         int     rc = 0;
3340
3341         /* Disable the single interface */
3342         if (fsg->config != 0) {
3343                 DBG(fsg, "reset config\n");
3344                 fsg->config = 0;
3345                 rc = do_set_interface(fsg, -1);
3346         }
3347
3348         /* Enable the interface */
3349         if (new_config != 0) {
3350                 fsg->config = new_config;
3351                 if ((rc = do_set_interface(fsg, 0)) != 0)
3352                         fsg->config = 0;        // Reset on errors
3353                 else {
3354                         char *speed;
3355
3356                         switch (fsg->gadget->speed) {
3357                         case USB_SPEED_LOW:     speed = "low";  break;
3358                         case USB_SPEED_FULL:    speed = "full"; break;
3359                         case USB_SPEED_HIGH:    speed = "high"; break;
3360                         default:                speed = "?";    break;
3361                         }
3362                         INFO(fsg, "%s speed config #%d\n", speed, fsg->config);
3363                 }
3364         }
3365         return rc;
3366 }
3367
3368
3369 /*-------------------------------------------------------------------------*/
3370
3371 static void handle_exception(struct fsg_dev *fsg)
3372 {
3373         siginfo_t               info;
3374         int                     sig;
3375         int                     i;
3376         int                     num_active;
3377         struct fsg_buffhd       *bh;
3378         enum fsg_state          old_state;
3379         u8                      new_config;
3380         struct lun              *curlun;
3381         unsigned int            exception_req_tag;
3382         int                     rc;
3383
3384         /* Clear the existing signals.  Anything but SIGUSR1 is converted
3385          * into a high-priority EXIT exception. */
3386         for (;;) {
3387                 sig = dequeue_signal_lock(current, &current->blocked, &info);
3388                 if (!sig)
3389                         break;
3390                 if (sig != SIGUSR1) {
3391                         if (fsg->state < FSG_STATE_EXIT)
3392                                 DBG(fsg, "Main thread exiting on signal\n");
3393                         raise_exception(fsg, FSG_STATE_EXIT);
3394                 }
3395         }
3396
3397         /* Cancel all the pending transfers */
3398         if (fsg->intreq_busy)
3399                 usb_ep_dequeue(fsg->intr_in, fsg->intreq);
3400         for (i = 0; i < NUM_BUFFERS; ++i) {
3401                 bh = &fsg->buffhds[i];
3402                 if (bh->inreq_busy)
3403                         usb_ep_dequeue(fsg->bulk_in, bh->inreq);
3404                 if (bh->outreq_busy)
3405                         usb_ep_dequeue(fsg->bulk_out, bh->outreq);
3406         }
3407
3408         /* Wait until everything is idle */
3409         for (;;) {
3410                 num_active = fsg->intreq_busy;
3411                 for (i = 0; i < NUM_BUFFERS; ++i) {
3412                         bh = &fsg->buffhds[i];
3413                         num_active += bh->inreq_busy + bh->outreq_busy;
3414                 }
3415                 if (num_active == 0)
3416                         break;
3417                 if (sleep_thread(fsg))
3418                         return;
3419         }
3420
3421         /* Clear out the controller's fifos */
3422         if (fsg->bulk_in_enabled)
3423                 usb_ep_fifo_flush(fsg->bulk_in);
3424         if (fsg->bulk_out_enabled)
3425                 usb_ep_fifo_flush(fsg->bulk_out);
3426         if (fsg->intr_in_enabled)
3427                 usb_ep_fifo_flush(fsg->intr_in);
3428
3429         /* Reset the I/O buffer states and pointers, the SCSI
3430          * state, and the exception.  Then invoke the handler. */
3431         spin_lock_irq(&fsg->lock);
3432
3433         for (i = 0; i < NUM_BUFFERS; ++i) {
3434                 bh = &fsg->buffhds[i];
3435                 bh->state = BUF_STATE_EMPTY;
3436         }
3437         fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain =
3438                         &fsg->buffhds[0];
3439
3440         exception_req_tag = fsg->exception_req_tag;
3441         new_config = fsg->new_config;
3442         old_state = fsg->state;
3443
3444         if (old_state == FSG_STATE_ABORT_BULK_OUT)
3445                 fsg->state = FSG_STATE_STATUS_PHASE;
3446         else {
3447                 for (i = 0; i < fsg->nluns; ++i) {
3448                         curlun = &fsg->luns[i];
3449                         curlun->prevent_medium_removal = 0;
3450                         curlun->sense_data = curlun->unit_attention_data =
3451                                         SS_NO_SENSE;
3452                         curlun->sense_data_info = 0;
3453                         curlun->info_valid = 0;
3454                 }
3455                 fsg->state = FSG_STATE_IDLE;
3456         }
3457         spin_unlock_irq(&fsg->lock);
3458
3459         /* Carry out any extra actions required for the exception */
3460         switch (old_state) {
3461         default:
3462                 break;
3463
3464         case FSG_STATE_ABORT_BULK_OUT:
3465                 send_status(fsg);
3466                 spin_lock_irq(&fsg->lock);
3467                 if (fsg->state == FSG_STATE_STATUS_PHASE)
3468                         fsg->state = FSG_STATE_IDLE;
3469                 spin_unlock_irq(&fsg->lock);
3470                 break;
3471
3472         case FSG_STATE_RESET:
3473                 /* In case we were forced against our will to halt a
3474                  * bulk endpoint, clear the halt now.  (The SuperH UDC
3475                  * requires this.) */
3476                 if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
3477                         usb_ep_clear_halt(fsg->bulk_in);
3478
3479                 if (transport_is_bbb()) {
3480                         if (fsg->ep0_req_tag == exception_req_tag)
3481                                 ep0_queue(fsg); // Complete the status stage
3482
3483                 } else if (transport_is_cbi())
3484                         send_status(fsg);       // Status by interrupt pipe
3485
3486                 /* Technically this should go here, but it would only be
3487                  * a waste of time.  Ditto for the INTERFACE_CHANGE and
3488                  * CONFIG_CHANGE cases. */
3489                 // for (i = 0; i < fsg->nluns; ++i)
3490                 //      fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3491                 break;
3492
3493         case FSG_STATE_INTERFACE_CHANGE:
3494                 rc = do_set_interface(fsg, 0);
3495                 if (fsg->ep0_req_tag != exception_req_tag)
3496                         break;
3497                 if (rc != 0)                    // STALL on errors
3498                         fsg_set_halt(fsg, fsg->ep0);
3499                 else                            // Complete the status stage
3500                         ep0_queue(fsg);
3501                 break;
3502
3503         case FSG_STATE_CONFIG_CHANGE:
3504                 rc = do_set_config(fsg, new_config);
3505                 if (fsg->ep0_req_tag != exception_req_tag)
3506                         break;
3507                 if (rc != 0)                    // STALL on errors
3508                         fsg_set_halt(fsg, fsg->ep0);
3509                 else                            // Complete the status stage
3510                         ep0_queue(fsg);
3511                 break;
3512
3513         case FSG_STATE_DISCONNECT:
3514                 fsync_all(fsg);
3515                 do_set_config(fsg, 0);          // Unconfigured state
3516                 break;
3517
3518         case FSG_STATE_EXIT:
3519         case FSG_STATE_TERMINATED:
3520                 do_set_config(fsg, 0);                  // Free resources
3521                 spin_lock_irq(&fsg->lock);
3522                 fsg->state = FSG_STATE_TERMINATED;      // Stop the thread
3523                 spin_unlock_irq(&fsg->lock);
3524                 break;
3525         }
3526 }
3527
3528
3529 /*-------------------------------------------------------------------------*/
3530
3531 static int fsg_main_thread(void *fsg_)
3532 {
3533         struct fsg_dev          *fsg = fsg_;
3534
3535         /* Allow the thread to be killed by a signal, but set the signal mask
3536          * to block everything but INT, TERM, KILL, and USR1. */
3537         allow_signal(SIGINT);
3538         allow_signal(SIGTERM);
3539         allow_signal(SIGKILL);
3540         allow_signal(SIGUSR1);
3541
3542         /* Allow the thread to be frozen */
3543         set_freezable();
3544
3545         /* Arrange for userspace references to be interpreted as kernel
3546          * pointers.  That way we can pass a kernel pointer to a routine
3547          * that expects a __user pointer and it will work okay. */
3548         set_fs(get_ds());
3549
3550         /* The main loop */
3551         while (fsg->state != FSG_STATE_TERMINATED) {
3552                 if (exception_in_progress(fsg) || signal_pending(current)) {
3553                         handle_exception(fsg);
3554                         continue;
3555                 }
3556
3557                 if (!fsg->running) {
3558                         sleep_thread(fsg);
3559                         continue;
3560                 }
3561
3562                 if (get_next_command(fsg))
3563                         continue;
3564
3565                 spin_lock_irq(&fsg->lock);
3566                 if (!exception_in_progress(fsg))
3567                         fsg->state = FSG_STATE_DATA_PHASE;
3568                 spin_unlock_irq(&fsg->lock);
3569
3570                 if (do_scsi_command(fsg) || finish_reply(fsg))
3571                         continue;
3572
3573                 spin_lock_irq(&fsg->lock);
3574                 if (!exception_in_progress(fsg))
3575                         fsg->state = FSG_STATE_STATUS_PHASE;
3576                 spin_unlock_irq(&fsg->lock);
3577
3578                 if (send_status(fsg))
3579                         continue;
3580
3581                 spin_lock_irq(&fsg->lock);
3582                 if (!exception_in_progress(fsg))
3583                         fsg->state = FSG_STATE_IDLE;
3584                 spin_unlock_irq(&fsg->lock);
3585                 }
3586
3587         spin_lock_irq(&fsg->lock);
3588         fsg->thread_task = NULL;
3589         spin_unlock_irq(&fsg->lock);
3590
3591         /* In case we are exiting because of a signal, unregister the
3592          * gadget driver and close the backing file. */
3593         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) {
3594                 usb_gadget_unregister_driver(&fsg_driver);
3595                 close_all_backing_files(fsg);
3596         }
3597
3598         /* Let the unbind and cleanup routines know the thread has exited */
3599         complete_and_exit(&fsg->thread_notifier, 0);
3600 }
3601
3602
3603 /*-------------------------------------------------------------------------*/
3604
3605 /* If the next two routines are called while the gadget is registered,
3606  * the caller must own fsg->filesem for writing. */
3607
3608 static int open_backing_file(struct lun *curlun, const char *filename)
3609 {
3610         int                             ro;
3611         struct file                     *filp = NULL;
3612         int                             rc = -EINVAL;
3613         struct inode                    *inode = NULL;
3614         loff_t                          size;
3615         loff_t                          num_sectors;
3616         loff_t                          min_sectors;
3617
3618         /* R/W if we can, R/O if we must */
3619         ro = curlun->ro;
3620         if (!ro) {
3621                 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
3622                 if (-EROFS == PTR_ERR(filp))
3623                         ro = 1;
3624         }
3625         if (ro)
3626                 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
3627         if (IS_ERR(filp)) {
3628                 LINFO(curlun, "unable to open backing file: %s\n", filename);
3629                 return PTR_ERR(filp);
3630         }
3631
3632         if (!(filp->f_mode & FMODE_WRITE))
3633                 ro = 1;
3634
3635         if (filp->f_path.dentry)
3636                 inode = filp->f_path.dentry->d_inode;
3637         if (inode && S_ISBLK(inode->i_mode)) {
3638                 if (bdev_read_only(inode->i_bdev))
3639                         ro = 1;
3640         } else if (!inode || !S_ISREG(inode->i_mode)) {
3641                 LINFO(curlun, "invalid file type: %s\n", filename);
3642                 goto out;
3643         }
3644
3645         /* If we can't read the file, it's no good.
3646          * If we can't write the file, use it read-only. */
3647         if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
3648                 LINFO(curlun, "file not readable: %s\n", filename);
3649                 goto out;
3650         }
3651         if (!(filp->f_op->write || filp->f_op->aio_write))
3652                 ro = 1;
3653
3654         size = i_size_read(inode->i_mapping->host);
3655         if (size < 0) {
3656                 LINFO(curlun, "unable to find file size: %s\n", filename);
3657                 rc = (int) size;
3658                 goto out;
3659         }
3660         num_sectors = size >> 9;        // File size in 512-byte blocks
3661         min_sectors = 1;
3662         if (mod_data.cdrom) {
3663                 num_sectors &= ~3;      // Reduce to a multiple of 2048
3664                 min_sectors = 300*4;    // Smallest track is 300 frames
3665                 if (num_sectors >= 256*60*75*4) {
3666                         num_sectors = (256*60*75 - 1) * 4;
3667                         LINFO(curlun, "file too big: %s\n", filename);
3668                         LINFO(curlun, "using only first %d blocks\n",
3669                                         (int) num_sectors);
3670                 }
3671         }
3672         if (num_sectors < min_sectors) {
3673                 LINFO(curlun, "file too small: %s\n", filename);
3674                 rc = -ETOOSMALL;
3675                 goto out;
3676         }
3677
3678         get_file(filp);
3679         curlun->ro = ro;
3680         curlun->filp = filp;
3681         curlun->file_length = size;
3682         curlun->num_sectors = num_sectors;
3683         LDBG(curlun, "open backing file: %s\n", filename);
3684         rc = 0;
3685
3686 out:
3687         filp_close(filp, current->files);
3688         return rc;
3689 }
3690
3691
3692 static void close_backing_file(struct lun *curlun)
3693 {
3694         if (curlun->filp) {
3695                 LDBG(curlun, "close backing file\n");
3696                 fput(curlun->filp);
3697                 curlun->filp = NULL;
3698         }
3699 }
3700
3701 static void close_all_backing_files(struct fsg_dev *fsg)
3702 {
3703         int     i;
3704
3705         for (i = 0; i < fsg->nluns; ++i)
3706                 close_backing_file(&fsg->luns[i]);
3707 }
3708
3709
3710 static ssize_t show_ro(struct device *dev, struct device_attribute *attr, char *buf)
3711 {
3712         struct lun      *curlun = dev_to_lun(dev);
3713
3714         return sprintf(buf, "%d\n", curlun->ro);
3715 }
3716
3717 static ssize_t show_file(struct device *dev, struct device_attribute *attr,
3718                 char *buf)
3719 {
3720         struct lun      *curlun = dev_to_lun(dev);
3721         struct fsg_dev  *fsg = dev_get_drvdata(dev);
3722         char            *p;
3723         ssize_t         rc;
3724
3725         down_read(&fsg->filesem);
3726         if (backing_file_is_open(curlun)) {     // Get the complete pathname
3727                 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
3728                 if (IS_ERR(p))
3729                         rc = PTR_ERR(p);
3730                 else {
3731                         rc = strlen(p);
3732                         memmove(buf, p, rc);
3733                         buf[rc] = '\n';         // Add a newline
3734                         buf[++rc] = 0;
3735                 }
3736         } else {                                // No file, return 0 bytes
3737                 *buf = 0;
3738                 rc = 0;
3739         }
3740         up_read(&fsg->filesem);
3741         return rc;
3742 }
3743
3744
3745 static ssize_t store_ro(struct device *dev, struct device_attribute *attr,
3746                 const char *buf, size_t count)
3747 {
3748         ssize_t         rc = count;
3749         struct lun      *curlun = dev_to_lun(dev);
3750         struct fsg_dev  *fsg = dev_get_drvdata(dev);
3751         int             i;
3752
3753         if (sscanf(buf, "%d", &i) != 1)
3754                 return -EINVAL;
3755
3756         /* Allow the write-enable status to change only while the backing file
3757          * is closed. */
3758         down_read(&fsg->filesem);
3759         if (backing_file_is_open(curlun)) {
3760                 LDBG(curlun, "read-only status change prevented\n");
3761                 rc = -EBUSY;
3762         } else {
3763                 curlun->ro = !!i;
3764                 LDBG(curlun, "read-only status set to %d\n", curlun->ro);
3765         }
3766         up_read(&fsg->filesem);
3767         return rc;
3768 }
3769
3770 static ssize_t store_file(struct device *dev, struct device_attribute *attr,
3771                 const char *buf, size_t count)
3772 {
3773         struct lun      *curlun = dev_to_lun(dev);
3774         struct fsg_dev  *fsg = dev_get_drvdata(dev);
3775         int             rc = 0;
3776
3777         if (curlun->prevent_medium_removal && backing_file_is_open(curlun)) {
3778                 LDBG(curlun, "eject attempt prevented\n");
3779                 return -EBUSY;                          // "Door is locked"
3780         }
3781
3782         /* Remove a trailing newline */
3783         if (count > 0 && buf[count-1] == '\n')
3784                 ((char *) buf)[count-1] = 0;            // Ugh!
3785
3786         /* Eject current medium */
3787         down_write(&fsg->filesem);
3788         if (backing_file_is_open(curlun)) {
3789                 close_backing_file(curlun);
3790                 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
3791         }
3792
3793         /* Load new medium */
3794         if (count > 0 && buf[0]) {
3795                 rc = open_backing_file(curlun, buf);
3796                 if (rc == 0)
3797                         curlun->unit_attention_data =
3798                                         SS_NOT_READY_TO_READY_TRANSITION;
3799         }
3800         up_write(&fsg->filesem);
3801         return (rc < 0 ? rc : count);
3802 }
3803
3804
3805 /* The write permissions and store_xxx pointers are set in fsg_bind() */
3806 static DEVICE_ATTR(ro, 0444, show_ro, NULL);
3807 static DEVICE_ATTR(file, 0444, show_file, NULL);
3808
3809
3810 /*-------------------------------------------------------------------------*/
3811
3812 static void fsg_release(struct kref *ref)
3813 {
3814         struct fsg_dev  *fsg = container_of(ref, struct fsg_dev, ref);
3815
3816         kfree(fsg->luns);
3817         kfree(fsg);
3818 }
3819
3820 static void lun_release(struct device *dev)
3821 {
3822         struct fsg_dev  *fsg = dev_get_drvdata(dev);
3823
3824         kref_put(&fsg->ref, fsg_release);
3825 }
3826
3827 static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
3828 {
3829         struct fsg_dev          *fsg = get_gadget_data(gadget);
3830         int                     i;
3831         struct lun              *curlun;
3832         struct usb_request      *req = fsg->ep0req;
3833
3834         DBG(fsg, "unbind\n");
3835         clear_bit(REGISTERED, &fsg->atomic_bitflags);
3836
3837         /* Unregister the sysfs attribute files and the LUNs */
3838         for (i = 0; i < fsg->nluns; ++i) {
3839                 curlun = &fsg->luns[i];
3840                 if (curlun->registered) {
3841                         device_remove_file(&curlun->dev, &dev_attr_ro);
3842                         device_remove_file(&curlun->dev, &dev_attr_file);
3843                         device_unregister(&curlun->dev);
3844                         curlun->registered = 0;
3845                 }
3846         }
3847
3848         /* If the thread isn't already dead, tell it to exit now */
3849         if (fsg->state != FSG_STATE_TERMINATED) {
3850                 raise_exception(fsg, FSG_STATE_EXIT);
3851                 wait_for_completion(&fsg->thread_notifier);
3852
3853                 /* The cleanup routine waits for this completion also */
3854                 complete(&fsg->thread_notifier);
3855         }
3856
3857         /* Free the data buffers */
3858         for (i = 0; i < NUM_BUFFERS; ++i)
3859                 kfree(fsg->buffhds[i].buf);
3860
3861         /* Free the request and buffer for endpoint 0 */
3862         if (req) {
3863                 kfree(req->buf);
3864                 usb_ep_free_request(fsg->ep0, req);
3865         }
3866
3867         set_gadget_data(gadget, NULL);
3868 }
3869
3870
3871 static int __init check_parameters(struct fsg_dev *fsg)
3872 {
3873         int     prot;
3874         int     gcnum;
3875
3876         /* Store the default values */
3877         mod_data.transport_type = USB_PR_BULK;
3878         mod_data.transport_name = "Bulk-only";
3879         mod_data.protocol_type = USB_SC_SCSI;
3880         mod_data.protocol_name = "Transparent SCSI";
3881
3882         /* Some peripheral controllers are known not to be able to
3883          * halt bulk endpoints correctly.  If one of them is present,
3884          * disable stalls.
3885          */
3886         if (gadget_is_sh(fsg->gadget) || gadget_is_at91(fsg->gadget))
3887                 mod_data.can_stall = 0;
3888
3889         if (mod_data.release == 0xffff) {       // Parameter wasn't set
3890                 /* The sa1100 controller is not supported */
3891                 if (gadget_is_sa1100(fsg->gadget))
3892                         gcnum = -1;
3893                 else
3894                         gcnum = usb_gadget_controller_number(fsg->gadget);
3895                 if (gcnum >= 0)
3896                         mod_data.release = 0x0300 + gcnum;
3897                 else {
3898                         WARNING(fsg, "controller '%s' not recognized\n",
3899                                 fsg->gadget->name);
3900                         mod_data.release = 0x0399;
3901                 }
3902         }
3903
3904         prot = simple_strtol(mod_data.protocol_parm, NULL, 0);
3905
3906 #ifdef CONFIG_USB_FILE_STORAGE_TEST
3907         if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) {
3908                 ;               // Use default setting
3909         } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) {
3910                 mod_data.transport_type = USB_PR_CB;
3911                 mod_data.transport_name = "Control-Bulk";
3912         } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) {
3913                 mod_data.transport_type = USB_PR_CBI;
3914                 mod_data.transport_name = "Control-Bulk-Interrupt";
3915         } else {
3916                 ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm);
3917                 return -EINVAL;
3918         }
3919
3920         if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 ||
3921                         prot == USB_SC_SCSI) {
3922                 ;               // Use default setting
3923         } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 ||
3924                         prot == USB_SC_RBC) {
3925                 mod_data.protocol_type = USB_SC_RBC;
3926                 mod_data.protocol_name = "RBC";
3927         } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 ||
3928                         strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 ||
3929                         prot == USB_SC_8020) {
3930                 mod_data.protocol_type = USB_SC_8020;
3931                 mod_data.protocol_name = "8020i (ATAPI)";
3932         } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 ||
3933                         prot == USB_SC_QIC) {
3934                 mod_data.protocol_type = USB_SC_QIC;
3935                 mod_data.protocol_name = "QIC-157";
3936         } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 ||
3937                         prot == USB_SC_UFI) {
3938                 mod_data.protocol_type = USB_SC_UFI;
3939                 mod_data.protocol_name = "UFI";
3940         } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 ||
3941                         prot == USB_SC_8070) {
3942                 mod_data.protocol_type = USB_SC_8070;
3943                 mod_data.protocol_name = "8070i";
3944         } else {
3945                 ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm);
3946                 return -EINVAL;
3947         }
3948
3949         mod_data.buflen &= PAGE_CACHE_MASK;
3950         if (mod_data.buflen <= 0) {
3951                 ERROR(fsg, "invalid buflen\n");
3952                 return -ETOOSMALL;
3953         }
3954 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
3955
3956         return 0;
3957 }
3958
3959
3960 static int __init fsg_bind(struct usb_gadget *gadget)
3961 {
3962         struct fsg_dev          *fsg = the_fsg;
3963         int                     rc;
3964         int                     i;
3965         struct lun              *curlun;
3966         struct usb_ep           *ep;
3967         struct usb_request      *req;
3968         char                    *pathbuf, *p;
3969
3970         fsg->gadget = gadget;
3971         set_gadget_data(gadget, fsg);
3972         fsg->ep0 = gadget->ep0;
3973         fsg->ep0->driver_data = fsg;
3974
3975         if ((rc = check_parameters(fsg)) != 0)
3976                 goto out;
3977
3978         if (mod_data.removable) {       // Enable the store_xxx attributes
3979                 dev_attr_file.attr.mode = 0644;
3980                 dev_attr_file.store = store_file;
3981                 if (!mod_data.cdrom) {
3982                         dev_attr_ro.attr.mode = 0644;
3983                         dev_attr_ro.store = store_ro;
3984                 }
3985         }
3986
3987         /* Find out how many LUNs there should be */
3988         i = mod_data.nluns;
3989         if (i == 0)
3990                 i = max(mod_data.num_filenames, 1u);
3991         if (i > MAX_LUNS) {
3992                 ERROR(fsg, "invalid number of LUNs: %d\n", i);
3993                 rc = -EINVAL;
3994                 goto out;
3995         }
3996
3997         /* Create the LUNs, open their backing files, and register the
3998          * LUN devices in sysfs. */
3999         fsg->luns = kzalloc(i * sizeof(struct lun), GFP_KERNEL);
4000         if (!fsg->luns) {
4001                 rc = -ENOMEM;
4002                 goto out;
4003         }
4004         fsg->nluns = i;
4005
4006         for (i = 0; i < fsg->nluns; ++i) {
4007                 curlun = &fsg->luns[i];
4008                 curlun->ro = mod_data.ro[i];
4009                 if (mod_data.cdrom)
4010                         curlun->ro = 1;
4011                 curlun->dev.release = lun_release;
4012                 curlun->dev.parent = &gadget->dev;
4013                 curlun->dev.driver = &fsg_driver.driver;
4014                 dev_set_drvdata(&curlun->dev, fsg);
4015                 dev_set_name(&curlun->dev,"%s-lun%d",
4016                              dev_name(&gadget->dev), i);
4017
4018                 if ((rc = device_register(&curlun->dev)) != 0) {
4019                         INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
4020                         goto out;
4021                 }
4022                 if ((rc = device_create_file(&curlun->dev,
4023                                         &dev_attr_ro)) != 0 ||
4024                                 (rc = device_create_file(&curlun->dev,
4025                                         &dev_attr_file)) != 0) {
4026                         device_unregister(&curlun->dev);
4027                         goto out;
4028                 }
4029                 curlun->registered = 1;
4030                 kref_get(&fsg->ref);
4031
4032                 if (mod_data.file[i] && *mod_data.file[i]) {
4033                         if ((rc = open_backing_file(curlun,
4034                                         mod_data.file[i])) != 0)
4035                                 goto out;
4036                 } else if (!mod_data.removable) {
4037                         ERROR(fsg, "no file given for LUN%d\n", i);
4038                         rc = -EINVAL;
4039                         goto out;
4040                 }
4041         }
4042
4043         /* Find all the endpoints we will use */
4044         usb_ep_autoconfig_reset(gadget);
4045         ep = usb_ep_autoconfig(gadget, &fs_bulk_in_desc);
4046         if (!ep)
4047                 goto autoconf_fail;
4048         ep->driver_data = fsg;          // claim the endpoint
4049         fsg->bulk_in = ep;
4050
4051         ep = usb_ep_autoconfig(gadget, &fs_bulk_out_desc);
4052         if (!ep)
4053                 goto autoconf_fail;
4054         ep->driver_data = fsg;          // claim the endpoint
4055         fsg->bulk_out = ep;
4056
4057         if (transport_is_cbi()) {
4058                 ep = usb_ep_autoconfig(gadget, &fs_intr_in_desc);
4059                 if (!ep)
4060                         goto autoconf_fail;
4061                 ep->driver_data = fsg;          // claim the endpoint
4062                 fsg->intr_in = ep;
4063         }
4064
4065         /* Fix up the descriptors */
4066         device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
4067         device_desc.idVendor = cpu_to_le16(mod_data.vendor);
4068         device_desc.idProduct = cpu_to_le16(mod_data.product);
4069         device_desc.bcdDevice = cpu_to_le16(mod_data.release);
4070
4071         i = (transport_is_cbi() ? 3 : 2);       // Number of endpoints
4072         intf_desc.bNumEndpoints = i;
4073         intf_desc.bInterfaceSubClass = mod_data.protocol_type;
4074         intf_desc.bInterfaceProtocol = mod_data.transport_type;
4075         fs_function[i + FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
4076
4077         if (gadget_is_dualspeed(gadget)) {
4078                 hs_function[i + HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
4079
4080                 /* Assume ep0 uses the same maxpacket value for both speeds */
4081                 dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
4082
4083                 /* Assume endpoint addresses are the same for both speeds */
4084                 hs_bulk_in_desc.bEndpointAddress =
4085                                 fs_bulk_in_desc.bEndpointAddress;
4086                 hs_bulk_out_desc.bEndpointAddress =
4087                                 fs_bulk_out_desc.bEndpointAddress;
4088                 hs_intr_in_desc.bEndpointAddress =
4089                                 fs_intr_in_desc.bEndpointAddress;
4090         }
4091
4092         if (gadget_is_otg(gadget))
4093                 otg_desc.bmAttributes |= USB_OTG_HNP;
4094
4095         rc = -ENOMEM;
4096
4097         /* Allocate the request and buffer for endpoint 0 */
4098         fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL);
4099         if (!req)
4100                 goto out;
4101         req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL);
4102         if (!req->buf)
4103                 goto out;
4104         req->complete = ep0_complete;
4105
4106         /* Allocate the data buffers */
4107         for (i = 0; i < NUM_BUFFERS; ++i) {
4108                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
4109
4110                 /* Allocate for the bulk-in endpoint.  We assume that
4111                  * the buffer will also work with the bulk-out (and
4112                  * interrupt-in) endpoint. */
4113                 bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL);
4114                 if (!bh->buf)
4115                         goto out;
4116                 bh->next = bh + 1;
4117         }
4118         fsg->buffhds[NUM_BUFFERS - 1].next = &fsg->buffhds[0];
4119
4120         /* This should reflect the actual gadget power source */
4121         usb_gadget_set_selfpowered(gadget);
4122
4123         snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
4124                         init_utsname()->sysname, init_utsname()->release,
4125                         gadget->name);
4126
4127         /* On a real device, serial[] would be loaded from permanent
4128          * storage.  We just encode it from the driver version string. */
4129         for (i = 0; i < sizeof(serial) - 2; i += 2) {
4130                 unsigned char           c = DRIVER_VERSION[i / 2];
4131
4132                 if (!c)
4133                         break;
4134                 sprintf(&serial[i], "%02X", c);
4135         }
4136
4137         fsg->thread_task = kthread_create(fsg_main_thread, fsg,
4138                         "file-storage-gadget");
4139         if (IS_ERR(fsg->thread_task)) {
4140                 rc = PTR_ERR(fsg->thread_task);
4141                 goto out;
4142         }
4143
4144         INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
4145         INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
4146
4147         pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
4148         for (i = 0; i < fsg->nluns; ++i) {
4149                 curlun = &fsg->luns[i];
4150                 if (backing_file_is_open(curlun)) {
4151                         p = NULL;
4152                         if (pathbuf) {
4153                                 p = d_path(&curlun->filp->f_path,
4154                                            pathbuf, PATH_MAX);
4155                                 if (IS_ERR(p))
4156                                         p = NULL;
4157                         }
4158                         LINFO(curlun, "ro=%d, file: %s\n",
4159                                         curlun->ro, (p ? p : "(error)"));
4160                 }
4161         }
4162         kfree(pathbuf);
4163
4164         DBG(fsg, "transport=%s (x%02x)\n",
4165                         mod_data.transport_name, mod_data.transport_type);
4166         DBG(fsg, "protocol=%s (x%02x)\n",
4167                         mod_data.protocol_name, mod_data.protocol_type);
4168         DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n",
4169                         mod_data.vendor, mod_data.product, mod_data.release);
4170         DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n",
4171                         mod_data.removable, mod_data.can_stall,
4172                         mod_data.cdrom, mod_data.buflen);
4173         DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
4174
4175         set_bit(REGISTERED, &fsg->atomic_bitflags);
4176
4177         /* Tell the thread to start working */
4178         wake_up_process(fsg->thread_task);
4179         return 0;
4180
4181 autoconf_fail:
4182         ERROR(fsg, "unable to autoconfigure all endpoints\n");
4183         rc = -ENOTSUPP;
4184
4185 out:
4186         fsg->state = FSG_STATE_TERMINATED;      // The thread is dead
4187         fsg_unbind(gadget);
4188         close_all_backing_files(fsg);
4189         complete(&fsg->thread_notifier);
4190         return rc;
4191 }
4192
4193
4194 /*-------------------------------------------------------------------------*/
4195
4196 static void fsg_suspend(struct usb_gadget *gadget)
4197 {
4198         struct fsg_dev          *fsg = get_gadget_data(gadget);
4199
4200         DBG(fsg, "suspend\n");
4201         set_bit(SUSPENDED, &fsg->atomic_bitflags);
4202 }
4203
4204 static void fsg_resume(struct usb_gadget *gadget)
4205 {
4206         struct fsg_dev          *fsg = get_gadget_data(gadget);
4207
4208         DBG(fsg, "resume\n");
4209         clear_bit(SUSPENDED, &fsg->atomic_bitflags);
4210 }
4211
4212
4213 /*-------------------------------------------------------------------------*/
4214
4215 static struct usb_gadget_driver         fsg_driver = {
4216 #ifdef CONFIG_USB_GADGET_DUALSPEED
4217         .speed          = USB_SPEED_HIGH,
4218 #else
4219         .speed          = USB_SPEED_FULL,
4220 #endif
4221         .function       = (char *) longname,
4222         .bind           = fsg_bind,
4223         .unbind         = fsg_unbind,
4224         .disconnect     = fsg_disconnect,
4225         .setup          = fsg_setup,
4226         .suspend        = fsg_suspend,
4227         .resume         = fsg_resume,
4228
4229         .driver         = {
4230                 .name           = (char *) shortname,
4231                 .owner          = THIS_MODULE,
4232                 // .release = ...
4233                 // .suspend = ...
4234                 // .resume = ...
4235         },
4236 };
4237
4238
4239 static int __init fsg_alloc(void)
4240 {
4241         struct fsg_dev          *fsg;
4242
4243         fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
4244         if (!fsg)
4245                 return -ENOMEM;
4246         spin_lock_init(&fsg->lock);
4247         init_rwsem(&fsg->filesem);
4248         kref_init(&fsg->ref);
4249         init_completion(&fsg->thread_notifier);
4250
4251         the_fsg = fsg;
4252         return 0;
4253 }
4254
4255
4256 static int __init fsg_init(void)
4257 {
4258         int             rc;
4259         struct fsg_dev  *fsg;
4260
4261         if ((rc = fsg_alloc()) != 0)
4262                 return rc;
4263         fsg = the_fsg;
4264         if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0)
4265                 kref_put(&fsg->ref, fsg_release);
4266         return rc;
4267 }
4268 module_init(fsg_init);
4269
4270
4271 static void __exit fsg_cleanup(void)
4272 {
4273         struct fsg_dev  *fsg = the_fsg;
4274
4275         /* Unregister the driver iff the thread hasn't already done so */
4276         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
4277                 usb_gadget_unregister_driver(&fsg_driver);
4278
4279         /* Wait for the thread to finish up */
4280         wait_for_completion(&fsg->thread_notifier);
4281
4282         close_all_backing_files(fsg);
4283         kref_put(&fsg->ref, fsg_release);
4284 }
4285 module_exit(fsg_cleanup);