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, release number and serial 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.
  73  *
  74  * Requirements are modest; only a bulk-in and a bulk-out endpoint are
  75  * needed (an interrupt-out endpoint is also needed for CBI).  The memory
  76  * requirement amounts to two 16K buffers, size configurable by a parameter.
  77  * Support is included for both full-speed and high-speed operation.
  78  *
  79  * Note that the driver is slightly non-portable in that it assumes a
  80  * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
  81  * interrupt-in endpoints.  With most device controllers this isn't an
  82  * issue, but there may be some with hardware restrictions that prevent
  83  * a buffer from being used by more than one endpoint.
  84  *
  85  * Module options:
  86  *
  87  *      file=filename[,filename...]
  88  *                              Required if "removable" is not set, names of
  89  *                                      the files or block devices used for
  90  *                                      backing storage
  91  *      serial=HHHH...          Required serial number (string of hex chars)
  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  *      nofua=b[,b...]          Default false, booleans for ignore FUA flag
  97  *                                      in SCSI WRITE(10,12) commands
  98  *      stall                   Default determined according to the type of
  99  *                                      USB device controller (usually true),
 100  *                                      boolean to permit the driver to halt
 101  *                                      bulk endpoints
 102  *      cdrom                   Default false, boolean for whether to emulate
 103  *                                      a CD-ROM drive
 104  *      transport=XXX           Default BBB, transport name (CB, CBI, or BBB)
 105  *      protocol=YYY            Default SCSI, protocol name (RBC, 8020 or
 106  *                                      ATAPI, QIC, UFI, 8070, or SCSI;
 107  *                                      also 1 - 6)
 108  *      vendor=0xVVVV           Default 0x0525 (NetChip), USB Vendor ID
 109  *      product=0xPPPP          Default 0xa4a5 (FSG), USB Product ID
 110  *      release=0xRRRR          Override the USB release number (bcdDevice)
 111  *      buflen=N                Default N=16384, buffer size used (will be
 112  *                                      rounded down to a multiple of
 113  *                                      PAGE_CACHE_SIZE)
 114  *
 115  * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "serial", "ro",
 116  * "removable", "luns", "nofua", "stall", and "cdrom" options are available;
 117  * default values are used for everything else.
 118  *
 119  * The pathnames of the backing files and the ro settings are available in
 120  * the attribute files "file", "nofua", and "ro" in the lun<n> subdirectory of
 121  * the gadget's sysfs directory.  If the "removable" option is set, writing to
 122  * these files will simulate ejecting/loading the medium (writing an empty
 123  * line means eject) and adjusting a write-enable tab.  Changes to the ro
 124  * setting are not allowed when the medium is loaded or if CD-ROM emulation
 125  * is being used.
 126  *
 127  * This gadget driver is heavily based on "Gadget Zero" by David Brownell.
 128  * The driver's SCSI command interface was based on the "Information
 129  * technology - Small Computer System Interface - 2" document from
 130  * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at
 131  * <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.  The single exception
 132  * is opcode 0x23 (READ FORMAT CAPACITIES), which was based on the
 133  * "Universal Serial Bus Mass Storage Class UFI Command Specification"
 134  * document, Revision 1.0, December 14, 1998, available at
 135  * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
 136  */
 137
 138
 139 /*
 140  *                              Driver Design
 141  *
 142  * The FSG driver is fairly straightforward.  There is a main kernel
 143  * thread that handles most of the work.  Interrupt routines field
 144  * callbacks from the controller driver: bulk- and interrupt-request
 145  * completion notifications, endpoint-0 events, and disconnect events.
 146  * Completion events are passed to the main thread by wakeup calls.  Many
 147  * ep0 requests are handled at interrupt time, but SetInterface,
 148  * SetConfiguration, and device reset requests are forwarded to the
 149  * thread in the form of "exceptions" using SIGUSR1 signals (since they
 150  * should interrupt any ongoing file I/O operations).
 151  *
 152  * The thread's main routine implements the standard command/data/status
 153  * parts of a SCSI interaction.  It and its subroutines are full of tests
 154  * for pending signals/exceptions -- all this polling is necessary since
 155  * the kernel has no setjmp/longjmp equivalents.  (Maybe this is an
 156  * indication that the driver really wants to be running in userspace.)
 157  * An important point is that so long as the thread is alive it keeps an
 158  * open reference to the backing file.  This will prevent unmounting
 159  * the backing file's underlying filesystem and could cause problems
 160  * during system shutdown, for example.  To prevent such problems, the
 161  * thread catches INT, TERM, and KILL signals and converts them into
 162  * an EXIT exception.
 163  *
 164  * In normal operation the main thread is started during the gadget's
 165  * fsg_bind() callback and stopped during fsg_unbind().  But it can also
 166  * exit when it receives a signal, and there's no point leaving the
 167  * gadget running when the thread is dead.  So just before the thread
 168  * exits, it deregisters the gadget driver.  This makes things a little
 169  * tricky: The driver is deregistered at two places, and the exiting
 170  * thread can indirectly call fsg_unbind() which in turn can tell the
 171  * thread to exit.  The first problem is resolved through the use of the
 172  * REGISTERED atomic bitflag; the driver will only be deregistered once.
 173  * The second problem is resolved by having fsg_unbind() check
 174  * fsg->state; it won't try to stop the thread if the state is already
 175  * FSG_STATE_TERMINATED.
 176  *
 177  * To provide maximum throughput, the driver uses a circular pipeline of
 178  * buffer heads (struct fsg_buffhd).  In principle the pipeline can be
 179  * arbitrarily long; in practice the benefits don't justify having more
 180  * than 2 stages (i.e., double buffering).  But it helps to think of the
 181  * pipeline as being a long one.  Each buffer head contains a bulk-in and
 182  * a bulk-out request pointer (since the buffer can be used for both
 183  * output and input -- directions always are given from the host's
 184  * point of view) as well as a pointer to the buffer and various state
 185  * variables.
 186  *
 187  * Use of the pipeline follows a simple protocol.  There is a variable
 188  * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
 189  * At any time that buffer head may still be in use from an earlier
 190  * request, so each buffer head has a state variable indicating whether
 191  * it is EMPTY, FULL, or BUSY.  Typical use involves waiting for the
 192  * buffer head to be EMPTY, filling the buffer either by file I/O or by
 193  * USB I/O (during which the buffer head is BUSY), and marking the buffer
 194  * head FULL when the I/O is complete.  Then the buffer will be emptied
 195  * (again possibly by USB I/O, during which it is marked BUSY) and
 196  * finally marked EMPTY again (possibly by a completion routine).
 197  *
 198  * A module parameter tells the driver to avoid stalling the bulk
 199  * endpoints wherever the transport specification allows.  This is
 200  * necessary for some UDCs like the SuperH, which cannot reliably clear a
 201  * halt on a bulk endpoint.  However, under certain circumstances the
 202  * Bulk-only specification requires a stall.  In such cases the driver
 203  * will halt the endpoint and set a flag indicating that it should clear
 204  * the halt in software during the next device reset.  Hopefully this
 205  * will permit everything to work correctly.  Furthermore, although the
 206  * specification allows the bulk-out endpoint to halt when the host sends
 207  * too much data, implementing this would cause an unavoidable race.
 208  * The driver will always use the "no-stall" approach for OUT transfers.
 209  *
 210  * One subtle point concerns sending status-stage responses for ep0
 211  * requests.  Some of these requests, such as device reset, can involve
 212  * interrupting an ongoing file I/O operation, which might take an
 213  * arbitrarily long time.  During that delay the host might give up on
 214  * the original ep0 request and issue a new one.  When that happens the
 215  * driver should not notify the host about completion of the original
 216  * request, as the host will no longer be waiting for it.  So the driver
 217  * assigns to each ep0 request a unique tag, and it keeps track of the
 218  * tag value of the request associated with a long-running exception
 219  * (device-reset, interface-change, or configuration-change).  When the
 220  * exception handler is finished, the status-stage response is submitted
 221  * only if the current ep0 request tag is equal to the exception request
 222  * tag.  Thus only the most recently received ep0 request will get a
 223  * status-stage response.
 224  *
 225  * Warning: This driver source file is too long.  It ought to be split up
 226  * into a header file plus about 3 separate .c files, to handle the details
 227  * of the Gadget, USB Mass Storage, and SCSI protocols.
 228  */
 229
 230
 231 /* #define VERBOSE_DEBUG */
 232 /* #define DUMP_MSGS */
 233
 234
 235 #include <linux/blkdev.h>
 236 #include <linux/completion.h>
 237 #include <linux/dcache.h>
 238 #include <linux/delay.h>
 239 #include <linux/device.h>
 240 #include <linux/fcntl.h>
 241 #include <linux/file.h>
 242 #include <linux/fs.h>
 243 #include <linux/kref.h>
 244 #include <linux/kthread.h>
 245 #include <linux/limits.h>
 246 #include <linux/rwsem.h>
 247 #include <linux/slab.h>
 248 #include <linux/spinlock.h>
 249 #include <linux/string.h>
 250 #include <linux/freezer.h>
 251 #include <linux/utsname.h>
 252
 253 #include <linux/usb/ch9.h>
 254 #include <linux/usb/gadget.h>
 255
 256 #include "gadget_chips.h"
 257
 258
 259
 260 /*
 261  * Kbuild is not very cooperative with respect to linking separately
 262  * compiled library objects into one module.  So for now we won't use
 263  * separate compilation ... ensuring init/exit sections work to shrink
 264  * the runtime footprint, and giving us at least some parts of what
 265  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
 266  */
 267 #include "usbstring.c"
 268 #include "config.c"
 269 #include "epautoconf.c"
 270
 271 /*-------------------------------------------------------------------------*/
 272
 273 #define DRIVER_DESC             "File-backed Storage Gadget"
 274 #define DRIVER_NAME             "g_file_storage"
 275 #define DRIVER_VERSION          "1 September 2010"
 276
 277 static       char fsg_string_manufacturer[64];
 278 static const char fsg_string_product[] = DRIVER_DESC;
 279 static const char fsg_string_config[] = "Self-powered";
 280 static const char fsg_string_interface[] = "Mass Storage";
 281
 282
 283 #include "storage_common.c"
 284
 285
 286 MODULE_DESCRIPTION(DRIVER_DESC);
 287 MODULE_AUTHOR("Alan Stern");
 288 MODULE_LICENSE("Dual BSD/GPL");
 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
 300 /* Encapsulate the module parameter settings */
 301
 302 static struct {
 303         char            *file[FSG_MAX_LUNS];
 304         char            *serial;
 305         int             ro[FSG_MAX_LUNS];
 306         int             nofua[FSG_MAX_LUNS];
 307         unsigned int    num_filenames;
 308         unsigned int    num_ros;
 309         unsigned int    num_nofuas;
 310         unsigned int    nluns;
 311
 312         int             removable;
 313         int             can_stall;
 314         int             cdrom;
 315
 316         char            *transport_parm;
 317         char            *protocol_parm;
 318         unsigned short  vendor;
 319         unsigned short  product;
 320         unsigned short  release;
 321         unsigned int    buflen;
 322
 323         int             transport_type;
 324         char            *transport_name;
 325         int             protocol_type;
 326         char            *protocol_name;
 327
 328 } mod_data = {                                  // Default values
 329         .transport_parm         = "BBB",
 330         .protocol_parm          = "SCSI",
 331         .removable              = 0,
 332         .can_stall              = 1,
 333         .cdrom                  = 0,
 334         .vendor                 = FSG_VENDOR_ID,
 335         .product                = FSG_PRODUCT_ID,
 336         .release                = 0xffff,       // Use controller chip type
 337         .buflen                 = 16384,
 338         };
 339
 340
 341 module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
 342                 S_IRUGO);
 343 MODULE_PARM_DESC(file, "names of backing files or devices");
 344
 345 module_param_named(serial, mod_data.serial, charp, S_IRUGO);
 346 MODULE_PARM_DESC(serial, "USB serial number");
 347
 348 module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
 349 MODULE_PARM_DESC(ro, "true to force read-only");
 350
 351 module_param_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas,
 352                 S_IRUGO);
 353 MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit");
 354
 355 module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
 356 MODULE_PARM_DESC(luns, "number of LUNs");
 357
 358 module_param_named(removable, mod_data.removable, bool, S_IRUGO);
 359 MODULE_PARM_DESC(removable, "true to simulate removable media");
 360
 361 module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
 362 MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
 363
 364 module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
 365 MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
 366
 367 /* In the non-TEST version, only the module parameters listed above
 368  * are available. */
 369 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 370
 371 module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
 372 MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
 373
 374 module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
 375 MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
 376                 "8070, or SCSI)");
 377
 378 module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
 379 MODULE_PARM_DESC(vendor, "USB Vendor ID");
 380
 381 module_param_named(product, mod_data.product, ushort, S_IRUGO);
 382 MODULE_PARM_DESC(product, "USB Product ID");
 383
 384 module_param_named(release, mod_data.release, ushort, S_IRUGO);
 385 MODULE_PARM_DESC(release, "USB release number");
 386
 387 module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
 388 MODULE_PARM_DESC(buflen, "I/O buffer size");
 389
 390 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 391
 392
 393 /*
 394  * These definitions will permit the compiler to avoid generating code for
 395  * parts of the driver that aren't used in the non-TEST version.  Even gcc
 396  * can recognize when a test of a constant expression yields a dead code
 397  * path.
 398  */
 399
 400 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 401
 402 #define transport_is_bbb()      (mod_data.transport_type == USB_PR_BULK)
 403 #define transport_is_cbi()      (mod_data.transport_type == USB_PR_CBI)
 404 #define protocol_is_scsi()      (mod_data.protocol_type == USB_SC_SCSI)
 405
 406 #else
 407
 408 #define transport_is_bbb()      1
 409 #define transport_is_cbi()      0
 410 #define protocol_is_scsi()      1
 411
 412 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 413
 414
 415 /*-------------------------------------------------------------------------*/
 416
 417
 418 struct fsg_dev {
 419         /* lock protects: state, all the req_busy's, and cbbuf_cmnd */
 420         spinlock_t              lock;
 421         struct usb_gadget       *gadget;
 422
 423         /* filesem protects: backing files in use */
 424         struct rw_semaphore     filesem;
 425
 426         /* reference counting: wait until all LUNs are released */
 427         struct kref             ref;
 428
 429         struct usb_ep           *ep0;           // Handy copy of gadget->ep0
 430         struct usb_request      *ep0req;        // For control responses
 431         unsigned int            ep0_req_tag;
 432         const char              *ep0req_name;
 433
 434         struct usb_request      *intreq;        // For interrupt responses
 435         int                     intreq_busy;
 436         struct fsg_buffhd       *intr_buffhd;
 437
 438         unsigned int            bulk_out_maxpacket;
 439         enum fsg_state          state;          // For exception handling
 440         unsigned int            exception_req_tag;
 441
 442         u8                      config, new_config;
 443
 444         unsigned int            running : 1;
 445         unsigned int            bulk_in_enabled : 1;
 446         unsigned int            bulk_out_enabled : 1;
 447         unsigned int            intr_in_enabled : 1;
 448         unsigned int            phase_error : 1;
 449         unsigned int            short_packet_received : 1;
 450         unsigned int            bad_lun_okay : 1;
 451
 452         unsigned long           atomic_bitflags;
 453 #define REGISTERED              0
 454 #define IGNORE_BULK_OUT         1
 455 #define SUSPENDED               2
 456
 457         struct usb_ep           *bulk_in;
 458         struct usb_ep           *bulk_out;
 459         struct usb_ep           *intr_in;
 460
 461         struct fsg_buffhd       *next_buffhd_to_fill;
 462         struct fsg_buffhd       *next_buffhd_to_drain;
 463
 464         int                     thread_wakeup_needed;
 465         struct completion       thread_notifier;
 466         struct task_struct      *thread_task;
 467
 468         int                     cmnd_size;
 469         u8                      cmnd[MAX_COMMAND_SIZE];
 470         enum data_direction     data_dir;
 471         u32                     data_size;
 472         u32                     data_size_from_cmnd;
 473         u32                     tag;
 474         unsigned int            lun;
 475         u32                     residue;
 476         u32                     usb_amount_left;
 477
 478         /* The CB protocol offers no way for a host to know when a command
 479          * has completed.  As a result the next command may arrive early,
 480          * and we will still have to handle it.  For that reason we need
 481          * a buffer to store new commands when using CB (or CBI, which
 482          * does not oblige a host to wait for command completion either). */
 483         int                     cbbuf_cmnd_size;
 484         u8                      cbbuf_cmnd[MAX_COMMAND_SIZE];
 485
 486         unsigned int            nluns;
 487         struct fsg_lun          *luns;
 488         struct fsg_lun          *curlun;
 489         /* Must be the last entry */
 490         struct fsg_buffhd       buffhds[];
 491 };
 492
 493 typedef void (*fsg_routine_t)(struct fsg_dev *);
 494
 495 static int exception_in_progress(struct fsg_dev *fsg)
 496 {
 497         return (fsg->state > FSG_STATE_IDLE);
 498 }
 499
 500 /* Make bulk-out requests be divisible by the maxpacket size */
 501 static void set_bulk_out_req_length(struct fsg_dev *fsg,
 502                 struct fsg_buffhd *bh, unsigned int length)
 503 {
 504         unsigned int    rem;
 505
 506         bh->bulk_out_intended_length = length;
 507         rem = length % fsg->bulk_out_maxpacket;
 508         if (rem > 0)
 509                 length += fsg->bulk_out_maxpacket - rem;
 510         bh->outreq->length = length;
 511 }
 512
 513 static struct fsg_dev                   *the_fsg;
 514 static struct usb_gadget_driver         fsg_driver;
 515
 516
 517 /*-------------------------------------------------------------------------*/
 518
 519 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 520 {
 521         const char      *name;
 522
 523         if (ep == fsg->bulk_in)
 524                 name = "bulk-in";
 525         else if (ep == fsg->bulk_out)
 526                 name = "bulk-out";
 527         else
 528                 name = ep->name;
 529         DBG(fsg, "%s set halt\n", name);
 530         return usb_ep_set_halt(ep);
 531 }
 532
 533
 534 /*-------------------------------------------------------------------------*/
 535
 536 /*
 537  * DESCRIPTORS ... most are static, but strings and (full) configuration
 538  * descriptors are built on demand.  Also the (static) config and interface
 539  * descriptors are adjusted during fsg_bind().
 540  */
 541
 542 /* There is only one configuration. */
 543 #define CONFIG_VALUE            1
 544
 545 static struct usb_device_descriptor
 546 device_desc = {
 547         .bLength =              sizeof device_desc,
 548         .bDescriptorType =      USB_DT_DEVICE,
 549
 550         .bcdUSB =               cpu_to_le16(0x0200),
 551         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 552
 553         /* The next three values can be overridden by module parameters */
 554         .idVendor =             cpu_to_le16(FSG_VENDOR_ID),
 555         .idProduct =            cpu_to_le16(FSG_PRODUCT_ID),
 556         .bcdDevice =            cpu_to_le16(0xffff),
 557
 558         .iManufacturer =        FSG_STRING_MANUFACTURER,
 559         .iProduct =             FSG_STRING_PRODUCT,
 560         .iSerialNumber =        FSG_STRING_SERIAL,
 561         .bNumConfigurations =   1,
 562 };
 563
 564 static struct usb_config_descriptor
 565 config_desc = {
 566         .bLength =              sizeof config_desc,
 567         .bDescriptorType =      USB_DT_CONFIG,
 568
 569         /* wTotalLength computed by usb_gadget_config_buf() */
 570         .bNumInterfaces =       1,
 571         .bConfigurationValue =  CONFIG_VALUE,
 572         .iConfiguration =       FSG_STRING_CONFIG,
 573         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 574         .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 575 };
 576
 577
 578 static struct usb_qualifier_descriptor
 579 dev_qualifier = {
 580         .bLength =              sizeof dev_qualifier,
 581         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 582
 583         .bcdUSB =               cpu_to_le16(0x0200),
 584         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 585
 586         .bNumConfigurations =   1,
 587 };
 588
 589 static int populate_bos(struct fsg_dev *fsg, u8 *buf)
 590 {
 591         memcpy(buf, &fsg_bos_desc, USB_DT_BOS_SIZE);
 592         buf += USB_DT_BOS_SIZE;
 593
 594         memcpy(buf, &fsg_ext_cap_desc, USB_DT_USB_EXT_CAP_SIZE);
 595         buf += USB_DT_USB_EXT_CAP_SIZE;
 596
 597         memcpy(buf, &fsg_ss_cap_desc, USB_DT_USB_SS_CAP_SIZE);
 598
 599         return USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE
 600                 + USB_DT_USB_EXT_CAP_SIZE;
 601 }
 602
 603 /*
 604  * Config descriptors must agree with the code that sets configurations
 605  * and with code managing interfaces and their altsettings.  They must
 606  * also handle different speeds and other-speed requests.
 607  */
 608 static int populate_config_buf(struct usb_gadget *gadget,
 609                 u8 *buf, u8 type, unsigned index)
 610 {
 611         enum usb_device_speed                   speed = gadget->speed;
 612         int                                     len;
 613         const struct usb_descriptor_header      **function;
 614
 615         if (index > 0)
 616                 return -EINVAL;
 617
 618         if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
 619                 speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
 620         function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH
 621                 ? (const struct usb_descriptor_header **)fsg_hs_function
 622                 : (const struct usb_descriptor_header **)fsg_fs_function;
 623
 624         /* for now, don't advertise srp-only devices */
 625         if (!gadget_is_otg(gadget))
 626                 function++;
 627
 628         len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
 629         ((struct usb_config_descriptor *) buf)->bDescriptorType = type;
 630         return len;
 631 }
 632
 633
 634 /*-------------------------------------------------------------------------*/
 635
 636 /* These routines may be called in process context or in_irq */
 637
 638 /* Caller must hold fsg->lock */
 639 static void wakeup_thread(struct fsg_dev *fsg)
 640 {
 641         /* Tell the main thread that something has happened */
 642         fsg->thread_wakeup_needed = 1;
 643         if (fsg->thread_task)
 644                 wake_up_process(fsg->thread_task);
 645 }
 646
 647
 648 static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
 649 {
 650         unsigned long           flags;
 651
 652         /* Do nothing if a higher-priority exception is already in progress.
 653          * If a lower-or-equal priority exception is in progress, preempt it
 654          * and notify the main thread by sending it a signal. */
 655         spin_lock_irqsave(&fsg->lock, flags);
 656         if (fsg->state <= new_state) {
 657                 fsg->exception_req_tag = fsg->ep0_req_tag;
 658                 fsg->state = new_state;
 659                 if (fsg->thread_task)
 660                         send_sig_info(SIGUSR1, SEND_SIG_FORCED,
 661                                         fsg->thread_task);
 662         }
 663         spin_unlock_irqrestore(&fsg->lock, flags);
 664 }
 665
 666
 667 /*-------------------------------------------------------------------------*/
 668
 669 /* The disconnect callback and ep0 routines.  These always run in_irq,
 670  * except that ep0_queue() is called in the main thread to acknowledge
 671  * completion of various requests: set config, set interface, and
 672  * Bulk-only device reset. */
 673
 674 static void fsg_disconnect(struct usb_gadget *gadget)
 675 {
 676         struct fsg_dev          *fsg = get_gadget_data(gadget);
 677
 678         DBG(fsg, "disconnect or port reset\n");
 679         raise_exception(fsg, FSG_STATE_DISCONNECT);
 680 }
 681
 682
 683 static int ep0_queue(struct fsg_dev *fsg)
 684 {
 685         int     rc;
 686
 687         rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
 688         if (rc != 0 && rc != -ESHUTDOWN) {
 689
 690                 /* We can't do much more than wait for a reset */
 691                 WARNING(fsg, "error in submission: %s --> %d\n",
 692                                 fsg->ep0->name, rc);
 693         }
 694         return rc;
 695 }
 696
 697 static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
 698 {
 699         struct fsg_dev          *fsg = ep->driver_data;
 700
 701         if (req->actual > 0)
 702                 dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
 703         if (req->status || req->actual != req->length)
 704                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 705                                 req->status, req->actual, req->length);
 706         if (req->status == -ECONNRESET)         // Request was cancelled
 707                 usb_ep_fifo_flush(ep);
 708
 709         if (req->status == 0 && req->context)
 710                 ((fsg_routine_t) (req->context))(fsg);
 711 }
 712
 713
 714 /*-------------------------------------------------------------------------*/
 715
 716 /* Bulk and interrupt endpoint completion handlers.
 717  * These always run in_irq. */
 718
 719 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
 720 {
 721         struct fsg_dev          *fsg = ep->driver_data;
 722         struct fsg_buffhd       *bh = req->context;
 723
 724         if (req->status || req->actual != req->length)
 725                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 726                                 req->status, req->actual, req->length);
 727         if (req->status == -ECONNRESET)         // Request was cancelled
 728                 usb_ep_fifo_flush(ep);
 729
 730         /* Hold the lock while we update the request and buffer states */
 731         smp_wmb();
 732         spin_lock(&fsg->lock);
 733         bh->inreq_busy = 0;
 734         bh->state = BUF_STATE_EMPTY;
 735         wakeup_thread(fsg);
 736         spin_unlock(&fsg->lock);
 737 }
 738
 739 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 740 {
 741         struct fsg_dev          *fsg = ep->driver_data;
 742         struct fsg_buffhd       *bh = req->context;
 743
 744         dump_msg(fsg, "bulk-out", req->buf, req->actual);
 745         if (req->status || req->actual != bh->bulk_out_intended_length)
 746                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 747                                 req->status, req->actual,
 748                                 bh->bulk_out_intended_length);
 749         if (req->status == -ECONNRESET)         // Request was cancelled
 750                 usb_ep_fifo_flush(ep);
 751
 752         /* Hold the lock while we update the request and buffer states */
 753         smp_wmb();
 754         spin_lock(&fsg->lock);
 755         bh->outreq_busy = 0;
 756         bh->state = BUF_STATE_FULL;
 757         wakeup_thread(fsg);
 758         spin_unlock(&fsg->lock);
 759 }
 760
 761
 762 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 763 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
 764 {
 765         struct fsg_dev          *fsg = ep->driver_data;
 766         struct fsg_buffhd       *bh = req->context;
 767
 768         if (req->status || req->actual != req->length)
 769                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 770                                 req->status, req->actual, req->length);
 771         if (req->status == -ECONNRESET)         // Request was cancelled
 772                 usb_ep_fifo_flush(ep);
 773
 774         /* Hold the lock while we update the request and buffer states */
 775         smp_wmb();
 776         spin_lock(&fsg->lock);
 777         fsg->intreq_busy = 0;
 778         bh->state = BUF_STATE_EMPTY;
 779         wakeup_thread(fsg);
 780         spin_unlock(&fsg->lock);
 781 }
 782
 783 #else
 784 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
 785 {}
 786 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 787
 788
 789 /*-------------------------------------------------------------------------*/
 790
 791 /* Ep0 class-specific handlers.  These always run in_irq. */
 792
 793 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 794 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 795 {
 796         struct usb_request      *req = fsg->ep0req;
 797         static u8               cbi_reset_cmnd[6] = {
 798                         SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
 799
 800         /* Error in command transfer? */
 801         if (req->status || req->length != req->actual ||
 802                         req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
 803
 804                 /* Not all controllers allow a protocol stall after
 805                  * receiving control-out data, but we'll try anyway. */
 806                 fsg_set_halt(fsg, fsg->ep0);
 807                 return;                 // Wait for reset
 808         }
 809
 810         /* Is it the special reset command? */
 811         if (req->actual >= sizeof cbi_reset_cmnd &&
 812                         memcmp(req->buf, cbi_reset_cmnd,
 813                                 sizeof cbi_reset_cmnd) == 0) {
 814
 815                 /* Raise an exception to stop the current operation
 816                  * and reinitialize our state. */
 817                 DBG(fsg, "cbi reset request\n");
 818                 raise_exception(fsg, FSG_STATE_RESET);
 819                 return;
 820         }
 821
 822         VDBG(fsg, "CB[I] accept device-specific command\n");
 823         spin_lock(&fsg->lock);
 824
 825         /* Save the command for later */
 826         if (fsg->cbbuf_cmnd_size)
 827                 WARNING(fsg, "CB[I] overwriting previous command\n");
 828         fsg->cbbuf_cmnd_size = req->actual;
 829         memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
 830
 831         wakeup_thread(fsg);
 832         spin_unlock(&fsg->lock);
 833 }
 834
 835 #else
 836 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 837 {}
 838 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 839
 840
 841 static int class_setup_req(struct fsg_dev *fsg,
 842                 const struct usb_ctrlrequest *ctrl)
 843 {
 844         struct usb_request      *req = fsg->ep0req;
 845         int                     value = -EOPNOTSUPP;
 846         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 847         u16                     w_value = le16_to_cpu(ctrl->wValue);
 848         u16                     w_length = le16_to_cpu(ctrl->wLength);
 849
 850         if (!fsg->config)
 851                 return value;
 852
 853         /* Handle Bulk-only class-specific requests */
 854         if (transport_is_bbb()) {
 855                 switch (ctrl->bRequest) {
 856
 857                 case USB_BULK_RESET_REQUEST:
 858                         if (ctrl->bRequestType != (USB_DIR_OUT |
 859                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 860                                 break;
 861                         if (w_index != 0 || w_value != 0) {
 862                                 value = -EDOM;
 863                                 break;
 864                         }
 865
 866                         /* Raise an exception to stop the current operation
 867                          * and reinitialize our state. */
 868                         DBG(fsg, "bulk reset request\n");
 869                         raise_exception(fsg, FSG_STATE_RESET);
 870                         value = DELAYED_STATUS;
 871                         break;
 872
 873                 case USB_BULK_GET_MAX_LUN_REQUEST:
 874                         if (ctrl->bRequestType != (USB_DIR_IN |
 875                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 876                                 break;
 877                         if (w_index != 0 || w_value != 0) {
 878                                 value = -EDOM;
 879                                 break;
 880                         }
 881                         VDBG(fsg, "get max LUN\n");
 882                         *(u8 *) req->buf = fsg->nluns - 1;
 883                         value = 1;
 884                         break;
 885                 }
 886         }
 887
 888         /* Handle CBI class-specific requests */
 889         else {
 890                 switch (ctrl->bRequest) {
 891
 892                 case USB_CBI_ADSC_REQUEST:
 893                         if (ctrl->bRequestType != (USB_DIR_OUT |
 894                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 895                                 break;
 896                         if (w_index != 0 || w_value != 0) {
 897                                 value = -EDOM;
 898                                 break;
 899                         }
 900                         if (w_length > MAX_COMMAND_SIZE) {
 901                                 value = -EOVERFLOW;
 902                                 break;
 903                         }
 904                         value = w_length;
 905                         fsg->ep0req->context = received_cbi_adsc;
 906                         break;
 907                 }
 908         }
 909
 910         if (value == -EOPNOTSUPP)
 911                 VDBG(fsg,
 912                         "unknown class-specific control req "
 913                         "%02x.%02x v%04x i%04x l%u\n",
 914                         ctrl->bRequestType, ctrl->bRequest,
 915                         le16_to_cpu(ctrl->wValue), w_index, w_length);
 916         return value;
 917 }
 918
 919
 920 /*-------------------------------------------------------------------------*/
 921
 922 /* Ep0 standard request handlers.  These always run in_irq. */
 923
 924 static int standard_setup_req(struct fsg_dev *fsg,
 925                 const struct usb_ctrlrequest *ctrl)
 926 {
 927         struct usb_request      *req = fsg->ep0req;
 928         int                     value = -EOPNOTSUPP;
 929         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 930         u16                     w_value = le16_to_cpu(ctrl->wValue);
 931
 932         /* Usually this just stores reply data in the pre-allocated ep0 buffer,
 933          * but config change events will also reconfigure hardware. */
 934         switch (ctrl->bRequest) {
 935
 936         case USB_REQ_GET_DESCRIPTOR:
 937                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
 938                                 USB_RECIP_DEVICE))
 939                         break;
 940                 switch (w_value >> 8) {
 941
 942                 case USB_DT_DEVICE:
 943                         VDBG(fsg, "get device descriptor\n");
 944                         device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
 945                         value = sizeof device_desc;
 946                         memcpy(req->buf, &device_desc, value);
 947                         break;
 948                 case USB_DT_DEVICE_QUALIFIER:
 949                         VDBG(fsg, "get device qualifier\n");
 950                         if (!gadget_is_dualspeed(fsg->gadget) ||
 951                                         fsg->gadget->speed == USB_SPEED_SUPER)
 952                                 break;
 953                         /*
 954                          * Assume ep0 uses the same maxpacket value for both
 955                          * speeds
 956                          */
 957                         dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
 958                         value = sizeof dev_qualifier;
 959                         memcpy(req->buf, &dev_qualifier, value);
 960                         break;
 961
 962                 case USB_DT_OTHER_SPEED_CONFIG:
 963                         VDBG(fsg, "get other-speed config descriptor\n");
 964                         if (!gadget_is_dualspeed(fsg->gadget) ||
 965                                         fsg->gadget->speed == USB_SPEED_SUPER)
 966                                 break;
 967                         goto get_config;
 968                 case USB_DT_CONFIG:
 969                         VDBG(fsg, "get configuration descriptor\n");
 970 get_config:
 971                         value = populate_config_buf(fsg->gadget,
 972                                         req->buf,
 973                                         w_value >> 8,
 974                                         w_value & 0xff);
 975                         break;
 976
 977                 case USB_DT_STRING:
 978                         VDBG(fsg, "get string descriptor\n");
 979
 980                         /* wIndex == language code */
 981                         value = usb_gadget_get_string(&fsg_stringtab,
 982                                         w_value & 0xff, req->buf);
 983                         break;
 984
 985                 case USB_DT_BOS:
 986                         VDBG(fsg, "get bos descriptor\n");
 987
 988                         if (gadget_is_superspeed(fsg->gadget))
 989                                 value = populate_bos(fsg, req->buf);
 990                         break;
 991                 }
 992
 993                 break;
 994
 995         /* One config, two speeds */
 996         case USB_REQ_SET_CONFIGURATION:
 997                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
 998                                 USB_RECIP_DEVICE))
 999                         break;
1000                 VDBG(fsg, "set configuration\n");
1001                 if (w_value == CONFIG_VALUE || w_value == 0) {
1002                         fsg->new_config = w_value;
1003
1004                         /* Raise an exception to wipe out previous transaction
1005                          * state (queued bufs, etc) and set the new config. */
1006                         raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
1007                         value = DELAYED_STATUS;
1008                 }
1009                 break;
1010         case USB_REQ_GET_CONFIGURATION:
1011                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1012                                 USB_RECIP_DEVICE))
1013                         break;
1014                 VDBG(fsg, "get configuration\n");
1015                 *(u8 *) req->buf = fsg->config;
1016                 value = 1;
1017                 break;
1018
1019         case USB_REQ_SET_INTERFACE:
1020                 if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD |
1021                                 USB_RECIP_INTERFACE))
1022                         break;
1023                 if (fsg->config && w_index == 0) {
1024
1025                         /* Raise an exception to wipe out previous transaction
1026                          * state (queued bufs, etc) and install the new
1027                          * interface altsetting. */
1028                         raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE);
1029                         value = DELAYED_STATUS;
1030                 }
1031                 break;
1032         case USB_REQ_GET_INTERFACE:
1033                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1034                                 USB_RECIP_INTERFACE))
1035                         break;
1036                 if (!fsg->config)
1037                         break;
1038                 if (w_index != 0) {
1039                         value = -EDOM;
1040                         break;
1041                 }
1042                 VDBG(fsg, "get interface\n");
1043                 *(u8 *) req->buf = 0;
1044                 value = 1;
1045                 break;
1046
1047         default:
1048                 VDBG(fsg,
1049                         "unknown control req %02x.%02x v%04x i%04x l%u\n",
1050                         ctrl->bRequestType, ctrl->bRequest,
1051                         w_value, w_index, le16_to_cpu(ctrl->wLength));
1052         }
1053
1054         return value;
1055 }
1056
1057
1058 static int fsg_setup(struct usb_gadget *gadget,
1059                 const struct usb_ctrlrequest *ctrl)
1060 {
1061         struct fsg_dev          *fsg = get_gadget_data(gadget);
1062         int                     rc;
1063         int                     w_length = le16_to_cpu(ctrl->wLength);
1064
1065         ++fsg->ep0_req_tag;             // Record arrival of a new request
1066         fsg->ep0req->context = NULL;
1067         fsg->ep0req->length = 0;
1068         dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
1069
1070         if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS)
1071                 rc = class_setup_req(fsg, ctrl);
1072         else
1073                 rc = standard_setup_req(fsg, ctrl);
1074
1075         /* Respond with data/status or defer until later? */
1076         if (rc >= 0 && rc != DELAYED_STATUS) {
1077                 rc = min(rc, w_length);
1078                 fsg->ep0req->length = rc;
1079                 fsg->ep0req->zero = rc < w_length;
1080                 fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
1081                                 "ep0-in" : "ep0-out");
1082                 rc = ep0_queue(fsg);
1083         }
1084
1085         /* Device either stalls (rc < 0) or reports success */
1086         return rc;
1087 }
1088
1089
1090 /*-------------------------------------------------------------------------*/
1091
1092 /* All the following routines run in process context */
1093
1094
1095 /* Use this for bulk or interrupt transfers, not ep0 */
1096 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
1097                 struct usb_request *req, int *pbusy,
1098                 enum fsg_buffer_state *state)
1099 {
1100         int     rc;
1101
1102         if (ep == fsg->bulk_in)
1103                 dump_msg(fsg, "bulk-in", req->buf, req->length);
1104         else if (ep == fsg->intr_in)
1105                 dump_msg(fsg, "intr-in", req->buf, req->length);
1106
1107         spin_lock_irq(&fsg->lock);
1108         *pbusy = 1;
1109         *state = BUF_STATE_BUSY;
1110         spin_unlock_irq(&fsg->lock);
1111         rc = usb_ep_queue(ep, req, GFP_KERNEL);
1112         if (rc != 0) {
1113                 *pbusy = 0;
1114                 *state = BUF_STATE_EMPTY;
1115
1116                 /* We can't do much more than wait for a reset */
1117
1118                 /* Note: currently the net2280 driver fails zero-length
1119                  * submissions if DMA is enabled. */
1120                 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
1121                                                 req->length == 0))
1122                         WARNING(fsg, "error in submission: %s --> %d\n",
1123                                         ep->name, rc);
1124         }
1125 }
1126
1127
1128 static int sleep_thread(struct fsg_dev *fsg)
1129 {
1130         int     rc = 0;
1131
1132         /* Wait until a signal arrives or we are woken up */
1133         for (;;) {
1134                 try_to_freeze();
1135                 set_current_state(TASK_INTERRUPTIBLE);
1136                 if (signal_pending(current)) {
1137                         rc = -EINTR;
1138                         break;
1139                 }
1140                 if (fsg->thread_wakeup_needed)
1141                         break;
1142                 schedule();
1143         }
1144         __set_current_state(TASK_RUNNING);
1145         fsg->thread_wakeup_needed = 0;
1146         return rc;
1147 }
1148
1149
1150 /*-------------------------------------------------------------------------*/
1151
1152 static int do_read(struct fsg_dev *fsg)
1153 {
1154         struct fsg_lun          *curlun = fsg->curlun;
1155         u32                     lba;
1156         struct fsg_buffhd       *bh;
1157         int                     rc;
1158         u32                     amount_left;
1159         loff_t                  file_offset, file_offset_tmp;
1160         unsigned int            amount;
1161         ssize_t                 nread;
1162
1163         /* Get the starting Logical Block Address and check that it's
1164          * not too big */
1165         if (fsg->cmnd[0] == READ_6)
1166                 lba = get_unaligned_be24(&fsg->cmnd[1]);
1167         else {
1168                 lba = get_unaligned_be32(&fsg->cmnd[2]);
1169
1170                 /* We allow DPO (Disable Page Out = don't save data in the
1171                  * cache) and FUA (Force Unit Access = don't read from the
1172                  * cache), but we don't implement them. */
1173                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1174                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1175                         return -EINVAL;
1176                 }
1177         }
1178         if (lba >= curlun->num_sectors) {
1179                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1180                 return -EINVAL;
1181         }
1182         file_offset = ((loff_t) lba) << curlun->blkbits;
1183
1184         /* Carry out the file reads */
1185         amount_left = fsg->data_size_from_cmnd;
1186         if (unlikely(amount_left == 0))
1187                 return -EIO;            // No default reply
1188
1189         for (;;) {
1190
1191                 /* Figure out how much we need to read:
1192                  * Try to read the remaining amount.
1193                  * But don't read more than the buffer size.
1194                  * And don't try to read past the end of the file.
1195                  */
1196                 amount = min((unsigned int) amount_left, mod_data.buflen);
1197                 amount = min((loff_t) amount,
1198                                 curlun->file_length - file_offset);
1199
1200                 /* Wait for the next buffer to become available */
1201                 bh = fsg->next_buffhd_to_fill;
1202                 while (bh->state != BUF_STATE_EMPTY) {
1203                         rc = sleep_thread(fsg);
1204                         if (rc)
1205                                 return rc;
1206                 }
1207
1208                 /* If we were asked to read past the end of file,
1209                  * end with an empty buffer. */
1210                 if (amount == 0) {
1211                         curlun->sense_data =
1212                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1213                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1214                         curlun->info_valid = 1;
1215                         bh->inreq->length = 0;
1216                         bh->state = BUF_STATE_FULL;
1217                         break;
1218                 }
1219
1220                 /* Perform the read */
1221                 file_offset_tmp = file_offset;
1222                 nread = vfs_read(curlun->filp,
1223                                 (char __user *) bh->buf,
1224                                 amount, &file_offset_tmp);
1225                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1226                                 (unsigned long long) file_offset,
1227                                 (int) nread);
1228                 if (signal_pending(current))
1229                         return -EINTR;
1230
1231                 if (nread < 0) {
1232                         LDBG(curlun, "error in file read: %d\n",
1233                                         (int) nread);
1234                         nread = 0;
1235                 } else if (nread < amount) {
1236                         LDBG(curlun, "partial file read: %d/%u\n",
1237                                         (int) nread, amount);
1238                         nread = round_down(nread, curlun->blksize);
1239                 }
1240                 file_offset  += nread;
1241                 amount_left  -= nread;
1242                 fsg->residue -= nread;
1243
1244                 /* Except at the end of the transfer, nread will be
1245                  * equal to the buffer size, which is divisible by the
1246                  * bulk-in maxpacket size.
1247                  */
1248                 bh->inreq->length = nread;
1249                 bh->state = BUF_STATE_FULL;
1250
1251                 /* If an error occurred, report it and its position */
1252                 if (nread < amount) {
1253                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1254                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1255                         curlun->info_valid = 1;
1256                         break;
1257                 }
1258
1259                 if (amount_left == 0)
1260                         break;          // No more left to read
1261
1262                 /* Send this buffer and go read some more */
1263                 bh->inreq->zero = 0;
1264                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1265                                 &bh->inreq_busy, &bh->state);
1266                 fsg->next_buffhd_to_fill = bh->next;
1267         }
1268
1269         return -EIO;            // No default reply
1270 }
1271
1272
1273 /*-------------------------------------------------------------------------*/
1274
1275 static int do_write(struct fsg_dev *fsg)
1276 {
1277         struct fsg_lun          *curlun = fsg->curlun;
1278         u32                     lba;
1279         struct fsg_buffhd       *bh;
1280         int                     get_some_more;
1281         u32                     amount_left_to_req, amount_left_to_write;
1282         loff_t                  usb_offset, file_offset, file_offset_tmp;
1283         unsigned int            amount;
1284         ssize_t                 nwritten;
1285         int                     rc;
1286
1287         if (curlun->ro) {
1288                 curlun->sense_data = SS_WRITE_PROTECTED;
1289                 return -EINVAL;
1290         }
1291         spin_lock(&curlun->filp->f_lock);
1292         curlun->filp->f_flags &= ~O_SYNC;       // Default is not to wait
1293         spin_unlock(&curlun->filp->f_lock);
1294
1295         /* Get the starting Logical Block Address and check that it's
1296          * not too big */
1297         if (fsg->cmnd[0] == WRITE_6)
1298                 lba = get_unaligned_be24(&fsg->cmnd[1]);
1299         else {
1300                 lba = get_unaligned_be32(&fsg->cmnd[2]);
1301
1302                 /* We allow DPO (Disable Page Out = don't save data in the
1303                  * cache) and FUA (Force Unit Access = write directly to the
1304                  * medium).  We don't implement DPO; we implement FUA by
1305                  * performing synchronous output. */
1306                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1307                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1308                         return -EINVAL;
1309                 }
1310                 /* FUA */
1311                 if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) {
1312                         spin_lock(&curlun->filp->f_lock);
1313                         curlun->filp->f_flags |= O_DSYNC;
1314                         spin_unlock(&curlun->filp->f_lock);
1315                 }
1316         }
1317         if (lba >= curlun->num_sectors) {
1318                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1319                 return -EINVAL;
1320         }
1321
1322         /* Carry out the file writes */
1323         get_some_more = 1;
1324         file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
1325         amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd;
1326
1327         while (amount_left_to_write > 0) {
1328
1329                 /* Queue a request for more data from the host */
1330                 bh = fsg->next_buffhd_to_fill;
1331                 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
1332
1333                         /* Figure out how much we want to get:
1334                          * Try to get the remaining amount,
1335                          * but not more than the buffer size.
1336                          */
1337                         amount = min(amount_left_to_req, mod_data.buflen);
1338
1339                         /* Beyond the end of the backing file? */
1340                         if (usb_offset >= curlun->file_length) {
1341                                 get_some_more = 0;
1342                                 curlun->sense_data =
1343                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1344                                 curlun->sense_data_info = usb_offset >> curlun->blkbits;
1345                                 curlun->info_valid = 1;
1346                                 continue;
1347                         }
1348
1349                         /* Get the next buffer */
1350                         usb_offset += amount;
1351                         fsg->usb_amount_left -= amount;
1352                         amount_left_to_req -= amount;
1353                         if (amount_left_to_req == 0)
1354                                 get_some_more = 0;
1355
1356                         /* Except at the end of the transfer, amount will be
1357                          * equal to the buffer size, which is divisible by
1358                          * the bulk-out maxpacket size.
1359                          */
1360                         set_bulk_out_req_length(fsg, bh, amount);
1361                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
1362                                         &bh->outreq_busy, &bh->state);
1363                         fsg->next_buffhd_to_fill = bh->next;
1364                         continue;
1365                 }
1366
1367                 /* Write the received data to the backing file */
1368                 bh = fsg->next_buffhd_to_drain;
1369                 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
1370                         break;                  // We stopped early
1371                 if (bh->state == BUF_STATE_FULL) {
1372                         smp_rmb();
1373                         fsg->next_buffhd_to_drain = bh->next;
1374                         bh->state = BUF_STATE_EMPTY;
1375
1376                         /* Did something go wrong with the transfer? */
1377                         if (bh->outreq->status != 0) {
1378                                 curlun->sense_data = SS_COMMUNICATION_FAILURE;
1379                                 curlun->sense_data_info = file_offset >> curlun->blkbits;
1380                                 curlun->info_valid = 1;
1381                                 break;
1382                         }
1383
1384                         amount = bh->outreq->actual;
1385                         if (curlun->file_length - file_offset < amount) {
1386                                 LERROR(curlun,
1387         "write %u @ %llu beyond end %llu\n",
1388         amount, (unsigned long long) file_offset,
1389         (unsigned long long) curlun->file_length);
1390                                 amount = curlun->file_length - file_offset;
1391                         }
1392
1393                         /* Don't accept excess data.  The spec doesn't say
1394                          * what to do in this case.  We'll ignore the error.
1395                          */
1396                         amount = min(amount, bh->bulk_out_intended_length);
1397
1398                         /* Don't write a partial block */
1399                         amount = round_down(amount, curlun->blksize);
1400                         if (amount == 0)
1401                                 goto empty_write;
1402
1403                         /* Perform the write */
1404                         file_offset_tmp = file_offset;
1405                         nwritten = vfs_write(curlun->filp,
1406                                         (char __user *) bh->buf,
1407                                         amount, &file_offset_tmp);
1408                         VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1409                                         (unsigned long long) file_offset,
1410                                         (int) nwritten);
1411                         if (signal_pending(current))
1412                                 return -EINTR;          // Interrupted!
1413
1414                         if (nwritten < 0) {
1415                                 LDBG(curlun, "error in file write: %d\n",
1416                                                 (int) nwritten);
1417                                 nwritten = 0;
1418                         } else if (nwritten < amount) {
1419                                 LDBG(curlun, "partial file write: %d/%u\n",
1420                                                 (int) nwritten, amount);
1421                                 nwritten = round_down(nwritten, curlun->blksize);
1422                         }
1423                         file_offset += nwritten;
1424                         amount_left_to_write -= nwritten;
1425                         fsg->residue -= nwritten;
1426
1427                         /* If an error occurred, report it and its position */
1428                         if (nwritten < amount) {
1429                                 curlun->sense_data = SS_WRITE_ERROR;
1430                                 curlun->sense_data_info = file_offset >> curlun->blkbits;
1431                                 curlun->info_valid = 1;
1432                                 break;
1433                         }
1434
1435  empty_write:
1436                         /* Did the host decide to stop early? */
1437                         if (bh->outreq->actual < bh->bulk_out_intended_length) {
1438                                 fsg->short_packet_received = 1;
1439                                 break;
1440                         }
1441                         continue;
1442                 }
1443
1444                 /* Wait for something to happen */
1445                 rc = sleep_thread(fsg);
1446                 if (rc)
1447                         return rc;
1448         }
1449
1450         return -EIO;            // No default reply
1451 }
1452
1453
1454 /*-------------------------------------------------------------------------*/
1455
1456 static int do_synchronize_cache(struct fsg_dev *fsg)
1457 {
1458         struct fsg_lun  *curlun = fsg->curlun;
1459         int             rc;
1460
1461         /* We ignore the requested LBA and write out all file's
1462          * dirty data buffers. */
1463         rc = fsg_lun_fsync_sub(curlun);
1464         if (rc)
1465                 curlun->sense_data = SS_WRITE_ERROR;
1466         return 0;
1467 }
1468
1469
1470 /*-------------------------------------------------------------------------*/
1471
1472 static void invalidate_sub(struct fsg_lun *curlun)
1473 {
1474         struct file     *filp = curlun->filp;
1475         struct inode    *inode = filp->f_path.dentry->d_inode;
1476         unsigned long   rc;
1477
1478         rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1479         VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1480 }
1481
1482 static int do_verify(struct fsg_dev *fsg)
1483 {
1484         struct fsg_lun          *curlun = fsg->curlun;
1485         u32                     lba;
1486         u32                     verification_length;
1487         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
1488         loff_t                  file_offset, file_offset_tmp;
1489         u32                     amount_left;
1490         unsigned int            amount;
1491         ssize_t                 nread;
1492
1493         /* Get the starting Logical Block Address and check that it's
1494          * not too big */
1495         lba = get_unaligned_be32(&fsg->cmnd[2]);
1496         if (lba >= curlun->num_sectors) {
1497                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1498                 return -EINVAL;
1499         }
1500
1501         /* We allow DPO (Disable Page Out = don't save data in the
1502          * cache) but we don't implement it. */
1503         if ((fsg->cmnd[1] & ~0x10) != 0) {
1504                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1505                 return -EINVAL;
1506         }
1507
1508         verification_length = get_unaligned_be16(&fsg->cmnd[7]);
1509         if (unlikely(verification_length == 0))
1510                 return -EIO;            // No default reply
1511
1512         /* Prepare to carry out the file verify */
1513         amount_left = verification_length << curlun->blkbits;
1514         file_offset = ((loff_t) lba) << curlun->blkbits;
1515
1516         /* Write out all the dirty buffers before invalidating them */
1517         fsg_lun_fsync_sub(curlun);
1518         if (signal_pending(current))
1519                 return -EINTR;
1520
1521         invalidate_sub(curlun);
1522         if (signal_pending(current))
1523                 return -EINTR;
1524
1525         /* Just try to read the requested blocks */
1526         while (amount_left > 0) {
1527
1528                 /* Figure out how much we need to read:
1529                  * Try to read the remaining amount, but not more than
1530                  * the buffer size.
1531                  * And don't try to read past the end of the file.
1532                  */
1533                 amount = min((unsigned int) amount_left, mod_data.buflen);
1534                 amount = min((loff_t) amount,
1535                                 curlun->file_length - file_offset);
1536                 if (amount == 0) {
1537                         curlun->sense_data =
1538                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1539                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1540                         curlun->info_valid = 1;
1541                         break;
1542                 }
1543
1544                 /* Perform the read */
1545                 file_offset_tmp = file_offset;
1546                 nread = vfs_read(curlun->filp,
1547                                 (char __user *) bh->buf,
1548                                 amount, &file_offset_tmp);
1549                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1550                                 (unsigned long long) file_offset,
1551                                 (int) nread);
1552                 if (signal_pending(current))
1553                         return -EINTR;
1554
1555                 if (nread < 0) {
1556                         LDBG(curlun, "error in file verify: %d\n",
1557                                         (int) nread);
1558                         nread = 0;
1559                 } else if (nread < amount) {
1560                         LDBG(curlun, "partial file verify: %d/%u\n",
1561                                         (int) nread, amount);
1562                         nread = round_down(nread, curlun->blksize);
1563                 }
1564                 if (nread == 0) {
1565                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1566                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1567                         curlun->info_valid = 1;
1568                         break;
1569                 }
1570                 file_offset += nread;
1571                 amount_left -= nread;
1572         }
1573         return 0;
1574 }
1575
1576
1577 /*-------------------------------------------------------------------------*/
1578
1579 static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1580 {
1581         u8      *buf = (u8 *) bh->buf;
1582
1583         static char vendor_id[] = "Linux   ";
1584         static char product_disk_id[] = "File-Stor Gadget";
1585         static char product_cdrom_id[] = "File-CD Gadget  ";
1586
1587         if (!fsg->curlun) {             // Unsupported LUNs are okay
1588                 fsg->bad_lun_okay = 1;
1589                 memset(buf, 0, 36);
1590                 buf[0] = 0x7f;          // Unsupported, no device-type
1591                 buf[4] = 31;            // Additional length
1592                 return 36;
1593         }
1594
1595         memset(buf, 0, 8);
1596         buf[0] = (mod_data.cdrom ? TYPE_ROM : TYPE_DISK);
1597         if (mod_data.removable)
1598                 buf[1] = 0x80;
1599         buf[2] = 2;             // ANSI SCSI level 2
1600         buf[3] = 2;             // SCSI-2 INQUIRY data format
1601         buf[4] = 31;            // Additional length
1602                                 // No special options
1603         sprintf(buf + 8, "%-8s%-16s%04x", vendor_id,
1604                         (mod_data.cdrom ? product_cdrom_id :
1605                                 product_disk_id),
1606                         mod_data.release);
1607         return 36;
1608 }
1609
1610
1611 static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1612 {
1613         struct fsg_lun  *curlun = fsg->curlun;
1614         u8              *buf = (u8 *) bh->buf;
1615         u32             sd, sdinfo;
1616         int             valid;
1617
1618         /*
1619          * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1620          *
1621          * If a REQUEST SENSE command is received from an initiator
1622          * with a pending unit attention condition (before the target
1623          * generates the contingent allegiance condition), then the
1624          * target shall either:
1625          *   a) report any pending sense data and preserve the unit
1626          *      attention condition on the logical unit, or,
1627          *   b) report the unit attention condition, may discard any
1628          *      pending sense data, and clear the unit attention
1629          *      condition on the logical unit for that initiator.
1630          *
1631          * FSG normally uses option a); enable this code to use option b).
1632          */
1633 #if 0
1634         if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1635                 curlun->sense_data = curlun->unit_attention_data;
1636                 curlun->unit_attention_data = SS_NO_SENSE;
1637         }
1638 #endif
1639
1640         if (!curlun) {          // Unsupported LUNs are okay
1641                 fsg->bad_lun_okay = 1;
1642                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1643                 sdinfo = 0;
1644                 valid = 0;
1645         } else {
1646                 sd = curlun->sense_data;
1647                 sdinfo = curlun->sense_data_info;
1648                 valid = curlun->info_valid << 7;
1649                 curlun->sense_data = SS_NO_SENSE;
1650                 curlun->sense_data_info = 0;
1651                 curlun->info_valid = 0;
1652         }
1653
1654         memset(buf, 0, 18);
1655         buf[0] = valid | 0x70;                  // Valid, current error
1656         buf[2] = SK(sd);
1657         put_unaligned_be32(sdinfo, &buf[3]);    /* Sense information */
1658         buf[7] = 18 - 8;                        // Additional sense length
1659         buf[12] = ASC(sd);
1660         buf[13] = ASCQ(sd);
1661         return 18;
1662 }
1663
1664
1665 static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1666 {
1667         struct fsg_lun  *curlun = fsg->curlun;
1668         u32             lba = get_unaligned_be32(&fsg->cmnd[2]);
1669         int             pmi = fsg->cmnd[8];
1670         u8              *buf = (u8 *) bh->buf;
1671
1672         /* Check the PMI and LBA fields */
1673         if (pmi > 1 || (pmi == 0 && lba != 0)) {
1674                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1675                 return -EINVAL;
1676         }
1677
1678         put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1679                                                 /* Max logical block */
1680         put_unaligned_be32(curlun->blksize, &buf[4]);   /* Block length */
1681         return 8;
1682 }
1683
1684
1685 static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1686 {
1687         struct fsg_lun  *curlun = fsg->curlun;
1688         int             msf = fsg->cmnd[1] & 0x02;
1689         u32             lba = get_unaligned_be32(&fsg->cmnd[2]);
1690         u8              *buf = (u8 *) bh->buf;
1691
1692         if ((fsg->cmnd[1] & ~0x02) != 0) {              /* Mask away MSF */
1693                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1694                 return -EINVAL;
1695         }
1696         if (lba >= curlun->num_sectors) {
1697                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1698                 return -EINVAL;
1699         }
1700
1701         memset(buf, 0, 8);
1702         buf[0] = 0x01;          /* 2048 bytes of user data, rest is EC */
1703         store_cdrom_address(&buf[4], msf, lba);
1704         return 8;
1705 }
1706
1707
1708 static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1709 {
1710         struct fsg_lun  *curlun = fsg->curlun;
1711         int             msf = fsg->cmnd[1] & 0x02;
1712         int             start_track = fsg->cmnd[6];
1713         u8              *buf = (u8 *) bh->buf;
1714
1715         if ((fsg->cmnd[1] & ~0x02) != 0 ||              /* Mask away MSF */
1716                         start_track > 1) {
1717                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1718                 return -EINVAL;
1719         }
1720
1721         memset(buf, 0, 20);
1722         buf[1] = (20-2);                /* TOC data length */
1723         buf[2] = 1;                     /* First track number */
1724         buf[3] = 1;                     /* Last track number */
1725         buf[5] = 0x16;                  /* Data track, copying allowed */
1726         buf[6] = 0x01;                  /* Only track is number 1 */
1727         store_cdrom_address(&buf[8], msf, 0);
1728
1729         buf[13] = 0x16;                 /* Lead-out track is data */
1730         buf[14] = 0xAA;                 /* Lead-out track number */
1731         store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1732         return 20;
1733 }
1734
1735
1736 static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1737 {
1738         struct fsg_lun  *curlun = fsg->curlun;
1739         int             mscmnd = fsg->cmnd[0];
1740         u8              *buf = (u8 *) bh->buf;
1741         u8              *buf0 = buf;
1742         int             pc, page_code;
1743         int             changeable_values, all_pages;
1744         int             valid_page = 0;
1745         int             len, limit;
1746
1747         if ((fsg->cmnd[1] & ~0x08) != 0) {              // Mask away DBD
1748                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1749                 return -EINVAL;
1750         }
1751         pc = fsg->cmnd[2] >> 6;
1752         page_code = fsg->cmnd[2] & 0x3f;
1753         if (pc == 3) {
1754                 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1755                 return -EINVAL;
1756         }
1757         changeable_values = (pc == 1);
1758         all_pages = (page_code == 0x3f);
1759
1760         /* Write the mode parameter header.  Fixed values are: default
1761          * medium type, no cache control (DPOFUA), and no block descriptors.
1762          * The only variable value is the WriteProtect bit.  We will fill in
1763          * the mode data length later. */
1764         memset(buf, 0, 8);
1765         if (mscmnd == MODE_SENSE) {
1766                 buf[2] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
1767                 buf += 4;
1768                 limit = 255;
1769         } else {                        // MODE_SENSE_10
1770                 buf[3] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
1771                 buf += 8;
1772                 limit = 65535;          // Should really be mod_data.buflen
1773         }
1774
1775         /* No block descriptors */
1776
1777         /* The mode pages, in numerical order.  The only page we support
1778          * is the Caching page. */
1779         if (page_code == 0x08 || all_pages) {
1780                 valid_page = 1;
1781                 buf[0] = 0x08;          // Page code
1782                 buf[1] = 10;            // Page length
1783                 memset(buf+2, 0, 10);   // None of the fields are changeable
1784
1785                 if (!changeable_values) {
1786                         buf[2] = 0x04;  // Write cache enable,
1787                                         // Read cache not disabled
1788                                         // No cache retention priorities
1789                         put_unaligned_be16(0xffff, &buf[4]);
1790                                         /* Don't disable prefetch */
1791                                         /* Minimum prefetch = 0 */
1792                         put_unaligned_be16(0xffff, &buf[8]);
1793                                         /* Maximum prefetch */
1794                         put_unaligned_be16(0xffff, &buf[10]);
1795                                         /* Maximum prefetch ceiling */
1796                 }
1797                 buf += 12;
1798         }
1799
1800         /* Check that a valid page was requested and the mode data length
1801          * isn't too long. */
1802         len = buf - buf0;
1803         if (!valid_page || len > limit) {
1804                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1805                 return -EINVAL;
1806         }
1807
1808         /*  Store the mode data length */
1809         if (mscmnd == MODE_SENSE)
1810                 buf0[0] = len - 1;
1811         else
1812                 put_unaligned_be16(len - 2, buf0);
1813         return len;
1814 }
1815
1816
1817 static int do_start_stop(struct fsg_dev *fsg)
1818 {
1819         struct fsg_lun  *curlun = fsg->curlun;
1820         int             loej, start;
1821
1822         if (!mod_data.removable) {
1823                 curlun->sense_data = SS_INVALID_COMMAND;
1824                 return -EINVAL;
1825         }
1826
1827         // int immed = fsg->cmnd[1] & 0x01;
1828         loej = fsg->cmnd[4] & 0x02;
1829         start = fsg->cmnd[4] & 0x01;
1830
1831 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1832         if ((fsg->cmnd[1] & ~0x01) != 0 ||              // Mask away Immed
1833                         (fsg->cmnd[4] & ~0x03) != 0) {  // Mask LoEj, Start
1834                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1835                 return -EINVAL;
1836         }
1837
1838         if (!start) {
1839
1840                 /* Are we allowed to unload the media? */
1841                 if (curlun->prevent_medium_removal) {
1842                         LDBG(curlun, "unload attempt prevented\n");
1843                         curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1844                         return -EINVAL;
1845                 }
1846                 if (loej) {             // Simulate an unload/eject
1847                         up_read(&fsg->filesem);
1848                         down_write(&fsg->filesem);
1849                         fsg_lun_close(curlun);
1850                         up_write(&fsg->filesem);
1851                         down_read(&fsg->filesem);
1852                 }
1853         } else {
1854
1855                 /* Our emulation doesn't support mounting; the medium is
1856                  * available for use as soon as it is loaded. */
1857                 if (!fsg_lun_is_open(curlun)) {
1858                         curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1859                         return -EINVAL;
1860                 }
1861         }
1862 #endif
1863         return 0;
1864 }
1865
1866
1867 static int do_prevent_allow(struct fsg_dev *fsg)
1868 {
1869         struct fsg_lun  *curlun = fsg->curlun;
1870         int             prevent;
1871
1872         if (!mod_data.removable) {
1873                 curlun->sense_data = SS_INVALID_COMMAND;
1874                 return -EINVAL;
1875         }
1876
1877         prevent = fsg->cmnd[4] & 0x01;
1878         if ((fsg->cmnd[4] & ~0x01) != 0) {              // Mask away Prevent
1879                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1880                 return -EINVAL;
1881         }
1882
1883         if (curlun->prevent_medium_removal && !prevent)
1884                 fsg_lun_fsync_sub(curlun);
1885         curlun->prevent_medium_removal = prevent;
1886         return 0;
1887 }
1888
1889
1890 static int do_read_format_capacities(struct fsg_dev *fsg,
1891                         struct fsg_buffhd *bh)
1892 {
1893         struct fsg_lun  *curlun = fsg->curlun;
1894         u8              *buf = (u8 *) bh->buf;
1895
1896         buf[0] = buf[1] = buf[2] = 0;
1897         buf[3] = 8;             // Only the Current/Maximum Capacity Descriptor
1898         buf += 4;
1899
1900         put_unaligned_be32(curlun->num_sectors, &buf[0]);
1901                                                 /* Number of blocks */
1902         put_unaligned_be32(curlun->blksize, &buf[4]);   /* Block length */
1903         buf[4] = 0x02;                          /* Current capacity */
1904         return 12;
1905 }
1906
1907
1908 static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1909 {
1910         struct fsg_lun  *curlun = fsg->curlun;
1911
1912         /* We don't support MODE SELECT */
1913         curlun->sense_data = SS_INVALID_COMMAND;
1914         return -EINVAL;
1915 }
1916
1917
1918 /*-------------------------------------------------------------------------*/
1919
1920 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1921 {
1922         int     rc;
1923
1924         rc = fsg_set_halt(fsg, fsg->bulk_in);
1925         if (rc == -EAGAIN)
1926                 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1927         while (rc != 0) {
1928                 if (rc != -EAGAIN) {
1929                         WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1930                         rc = 0;
1931                         break;
1932                 }
1933
1934                 /* Wait for a short time and then try again */
1935                 if (msleep_interruptible(100) != 0)
1936                         return -EINTR;
1937                 rc = usb_ep_set_halt(fsg->bulk_in);
1938         }
1939         return rc;
1940 }
1941
1942 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1943 {
1944         int     rc;
1945
1946         DBG(fsg, "bulk-in set wedge\n");
1947         rc = usb_ep_set_wedge(fsg->bulk_in);
1948         if (rc == -EAGAIN)
1949                 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1950         while (rc != 0) {
1951                 if (rc != -EAGAIN) {
1952                         WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1953                         rc = 0;
1954                         break;
1955                 }
1956
1957                 /* Wait for a short time and then try again */
1958                 if (msleep_interruptible(100) != 0)
1959                         return -EINTR;
1960                 rc = usb_ep_set_wedge(fsg->bulk_in);
1961         }
1962         return rc;
1963 }
1964
1965 static int throw_away_data(struct fsg_dev *fsg)
1966 {
1967         struct fsg_buffhd       *bh;
1968         u32                     amount;
1969         int                     rc;
1970
1971         while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY ||
1972                         fsg->usb_amount_left > 0) {
1973
1974                 /* Throw away the data in a filled buffer */
1975                 if (bh->state == BUF_STATE_FULL) {
1976                         smp_rmb();
1977                         bh->state = BUF_STATE_EMPTY;
1978                         fsg->next_buffhd_to_drain = bh->next;
1979
1980                         /* A short packet or an error ends everything */
1981                         if (bh->outreq->actual < bh->bulk_out_intended_length ||
1982                                         bh->outreq->status != 0) {
1983                                 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
1984                                 return -EINTR;
1985                         }
1986                         continue;
1987                 }
1988
1989                 /* Try to submit another request if we need one */
1990                 bh = fsg->next_buffhd_to_fill;
1991                 if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
1992                         amount = min(fsg->usb_amount_left,
1993                                         (u32) mod_data.buflen);
1994
1995                         /* Except at the end of the transfer, amount will be
1996                          * equal to the buffer size, which is divisible by
1997                          * the bulk-out maxpacket size.
1998                          */
1999                         set_bulk_out_req_length(fsg, bh, amount);
2000                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
2001                                         &bh->outreq_busy, &bh->state);
2002                         fsg->next_buffhd_to_fill = bh->next;
2003                         fsg->usb_amount_left -= amount;
2004                         continue;
2005                 }
2006
2007                 /* Otherwise wait for something to happen */
2008                 rc = sleep_thread(fsg);
2009                 if (rc)
2010                         return rc;
2011         }
2012         return 0;
2013 }
2014
2015
2016 static int finish_reply(struct fsg_dev *fsg)
2017 {
2018         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
2019         int                     rc = 0;
2020
2021         switch (fsg->data_dir) {
2022         case DATA_DIR_NONE:
2023                 break;                  // Nothing to send
2024
2025         /* If we don't know whether the host wants to read or write,
2026          * this must be CB or CBI with an unknown command.  We mustn't
2027          * try to send or receive any data.  So stall both bulk pipes
2028          * if we can and wait for a reset. */
2029         case DATA_DIR_UNKNOWN:
2030                 if (mod_data.can_stall) {
2031                         fsg_set_halt(fsg, fsg->bulk_out);
2032                         rc = halt_bulk_in_endpoint(fsg);
2033                 }
2034                 break;
2035
2036         /* All but the last buffer of data must have already been sent */
2037         case DATA_DIR_TO_HOST:
2038                 if (fsg->data_size == 0)
2039                         ;               // Nothing to send
2040
2041                 /* If there's no residue, simply send the last buffer */
2042                 else if (fsg->residue == 0) {
2043                         bh->inreq->zero = 0;
2044                         start_transfer(fsg, fsg->bulk_in, bh->inreq,
2045                                         &bh->inreq_busy, &bh->state);
2046                         fsg->next_buffhd_to_fill = bh->next;
2047                 }
2048
2049                 /* There is a residue.  For CB and CBI, simply mark the end
2050                  * of the data with a short packet.  However, if we are
2051                  * allowed to stall, there was no data at all (residue ==
2052                  * data_size), and the command failed (invalid LUN or
2053                  * sense data is set), then halt the bulk-in endpoint
2054                  * instead. */
2055                 else if (!transport_is_bbb()) {
2056                         if (mod_data.can_stall &&
2057                                         fsg->residue == fsg->data_size &&
2058         (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) {
2059                                 bh->state = BUF_STATE_EMPTY;
2060                                 rc = halt_bulk_in_endpoint(fsg);
2061                         } else {
2062                                 bh->inreq->zero = 1;
2063                                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2064                                                 &bh->inreq_busy, &bh->state);
2065                                 fsg->next_buffhd_to_fill = bh->next;
2066                         }
2067                 }
2068
2069                 /*
2070                  * For Bulk-only, mark the end of the data with a short
2071                  * packet.  If we are allowed to stall, halt the bulk-in
2072                  * endpoint.  (Note: This violates the Bulk-Only Transport
2073                  * specification, which requires us to pad the data if we
2074                  * don't halt the endpoint.  Presumably nobody will mind.)
2075                  */
2076                 else {
2077                         bh->inreq->zero = 1;
2078                         start_transfer(fsg, fsg->bulk_in, bh->inreq,
2079                                         &bh->inreq_busy, &bh->state);
2080                         fsg->next_buffhd_to_fill = bh->next;
2081                         if (mod_data.can_stall)
2082                                 rc = halt_bulk_in_endpoint(fsg);
2083                 }
2084                 break;
2085
2086         /* We have processed all we want from the data the host has sent.
2087          * There may still be outstanding bulk-out requests. */
2088         case DATA_DIR_FROM_HOST:
2089                 if (fsg->residue == 0)
2090                         ;               // Nothing to receive
2091
2092                 /* Did the host stop sending unexpectedly early? */
2093                 else if (fsg->short_packet_received) {
2094                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2095                         rc = -EINTR;
2096                 }
2097
2098                 /* We haven't processed all the incoming data.  Even though
2099                  * we may be allowed to stall, doing so would cause a race.
2100                  * The controller may already have ACK'ed all the remaining
2101                  * bulk-out packets, in which case the host wouldn't see a
2102                  * STALL.  Not realizing the endpoint was halted, it wouldn't
2103                  * clear the halt -- leading to problems later on. */
2104 #if 0
2105                 else if (mod_data.can_stall) {
2106                         fsg_set_halt(fsg, fsg->bulk_out);
2107                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2108                         rc = -EINTR;
2109                 }
2110 #endif
2111
2112                 /* We can't stall.  Read in the excess data and throw it
2113                  * all away. */
2114                 else
2115                         rc = throw_away_data(fsg);
2116                 break;
2117         }
2118         return rc;
2119 }
2120
2121
2122 static int send_status(struct fsg_dev *fsg)
2123 {
2124         struct fsg_lun          *curlun = fsg->curlun;
2125         struct fsg_buffhd       *bh;
2126         int                     rc;
2127         u8                      status = USB_STATUS_PASS;
2128         u32                     sd, sdinfo = 0;
2129
2130         /* Wait for the next buffer to become available */
2131         bh = fsg->next_buffhd_to_fill;
2132         while (bh->state != BUF_STATE_EMPTY) {
2133                 rc = sleep_thread(fsg);
2134                 if (rc)
2135                         return rc;
2136         }
2137
2138         if (curlun) {
2139                 sd = curlun->sense_data;
2140                 sdinfo = curlun->sense_data_info;
2141         } else if (fsg->bad_lun_okay)
2142                 sd = SS_NO_SENSE;
2143         else
2144                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2145
2146         if (fsg->phase_error) {
2147                 DBG(fsg, "sending phase-error status\n");
2148                 status = USB_STATUS_PHASE_ERROR;
2149                 sd = SS_INVALID_COMMAND;
2150         } else if (sd != SS_NO_SENSE) {
2151                 DBG(fsg, "sending command-failure status\n");
2152                 status = USB_STATUS_FAIL;
2153                 VDBG(fsg, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
2154                                 "  info x%x\n",
2155                                 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
2156         }
2157
2158         if (transport_is_bbb()) {
2159                 struct bulk_cs_wrap     *csw = bh->buf;
2160
2161                 /* Store and send the Bulk-only CSW */
2162                 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
2163                 csw->Tag = fsg->tag;
2164                 csw->Residue = cpu_to_le32(fsg->residue);
2165                 csw->Status = status;
2166
2167                 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
2168                 bh->inreq->zero = 0;
2169                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2170                                 &bh->inreq_busy, &bh->state);
2171
2172         } else if (mod_data.transport_type == USB_PR_CB) {
2173
2174                 /* Control-Bulk transport has no status phase! */
2175                 return 0;
2176
2177         } else {                        // USB_PR_CBI
2178                 struct interrupt_data   *buf = bh->buf;
2179
2180                 /* Store and send the Interrupt data.  UFI sends the ASC
2181                  * and ASCQ bytes.  Everything else sends a Type (which
2182                  * is always 0) and the status Value. */
2183                 if (mod_data.protocol_type == USB_SC_UFI) {
2184                         buf->bType = ASC(sd);
2185                         buf->bValue = ASCQ(sd);
2186                 } else {
2187                         buf->bType = 0;
2188                         buf->bValue = status;
2189                 }
2190                 fsg->intreq->length = CBI_INTERRUPT_DATA_LEN;
2191
2192                 fsg->intr_buffhd = bh;          // Point to the right buffhd
2193                 fsg->intreq->buf = bh->inreq->buf;
2194                 fsg->intreq->context = bh;
2195                 start_transfer(fsg, fsg->intr_in, fsg->intreq,
2196                                 &fsg->intreq_busy, &bh->state);
2197         }
2198
2199         fsg->next_buffhd_to_fill = bh->next;
2200         return 0;
2201 }
2202
2203
2204 /*-------------------------------------------------------------------------*/
2205
2206 /* Check whether the command is properly formed and whether its data size
2207  * and direction agree with the values we already have. */
2208 static int check_command(struct fsg_dev *fsg, int cmnd_size,
2209                 enum data_direction data_dir, unsigned int mask,
2210                 int needs_medium, const char *name)
2211 {
2212         int                     i;
2213         int                     lun = fsg->cmnd[1] >> 5;
2214         static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
2215         char                    hdlen[20];
2216         struct fsg_lun          *curlun;
2217
2218         /* Adjust the expected cmnd_size for protocol encapsulation padding.
2219          * Transparent SCSI doesn't pad. */
2220         if (protocol_is_scsi())
2221                 ;
2222
2223         /* There's some disagreement as to whether RBC pads commands or not.
2224          * We'll play it safe and accept either form. */
2225         else if (mod_data.protocol_type == USB_SC_RBC) {
2226                 if (fsg->cmnd_size == 12)
2227                         cmnd_size = 12;
2228
2229         /* All the other protocols pad to 12 bytes */
2230         } else
2231                 cmnd_size = 12;
2232
2233         hdlen[0] = 0;
2234         if (fsg->data_dir != DATA_DIR_UNKNOWN)
2235                 sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
2236                                 fsg->data_size);
2237         VDBG(fsg, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
2238                         name, cmnd_size, dirletter[(int) data_dir],
2239                         fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen);
2240
2241         /* We can't reply at all until we know the correct data direction
2242          * and size. */
2243         if (fsg->data_size_from_cmnd == 0)
2244                 data_dir = DATA_DIR_NONE;
2245         if (fsg->data_dir == DATA_DIR_UNKNOWN) {        // CB or CBI
2246                 fsg->data_dir = data_dir;
2247                 fsg->data_size = fsg->data_size_from_cmnd;
2248
2249         } else {                                        // Bulk-only
2250                 if (fsg->data_size < fsg->data_size_from_cmnd) {
2251
2252                         /* Host data size < Device data size is a phase error.
2253                          * Carry out the command, but only transfer as much
2254                          * as we are allowed. */
2255                         fsg->data_size_from_cmnd = fsg->data_size;
2256                         fsg->phase_error = 1;
2257                 }
2258         }
2259         fsg->residue = fsg->usb_amount_left = fsg->data_size;
2260
2261         /* Conflicting data directions is a phase error */
2262         if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
2263                 fsg->phase_error = 1;
2264                 return -EINVAL;
2265         }
2266
2267         /* Verify the length of the command itself */
2268         if (cmnd_size != fsg->cmnd_size) {
2269
2270                 /* Special case workaround: There are plenty of buggy SCSI
2271                  * implementations. Many have issues with cbw->Length
2272                  * field passing a wrong command size. For those cases we
2273                  * always try to work around the problem by using the length
2274                  * sent by the host side provided it is at least as large
2275                  * as the correct command length.
2276                  * Examples of such cases would be MS-Windows, which issues
2277                  * REQUEST SENSE with cbw->Length == 12 where it should
2278                  * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
2279                  * REQUEST SENSE with cbw->Length == 10 where it should
2280                  * be 6 as well.
2281                  */
2282                 if (cmnd_size <= fsg->cmnd_size) {
2283                         DBG(fsg, "%s is buggy! Expected length %d "
2284                                         "but we got %d\n", name,
2285                                         cmnd_size, fsg->cmnd_size);
2286                         cmnd_size = fsg->cmnd_size;
2287                 } else {
2288                         fsg->phase_error = 1;
2289                         return -EINVAL;
2290                 }
2291         }
2292
2293         /* Check that the LUN values are consistent */
2294         if (transport_is_bbb()) {
2295                 if (fsg->lun != lun)
2296                         DBG(fsg, "using LUN %d from CBW, "
2297                                         "not LUN %d from CDB\n",
2298                                         fsg->lun, lun);
2299         } else
2300                 fsg->lun = lun;         // Use LUN from the command
2301
2302         /* Check the LUN */
2303         if (fsg->lun < fsg->nluns) {
2304                 fsg->curlun = curlun = &fsg->luns[fsg->lun];
2305                 if (fsg->cmnd[0] != REQUEST_SENSE) {
2306                         curlun->sense_data = SS_NO_SENSE;
2307                         curlun->sense_data_info = 0;
2308                         curlun->info_valid = 0;
2309                 }
2310         } else {
2311                 fsg->curlun = curlun = NULL;
2312                 fsg->bad_lun_okay = 0;
2313
2314                 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
2315                  * to use unsupported LUNs; all others may not. */
2316                 if (fsg->cmnd[0] != INQUIRY &&
2317                                 fsg->cmnd[0] != REQUEST_SENSE) {
2318                         DBG(fsg, "unsupported LUN %d\n", fsg->lun);
2319                         return -EINVAL;
2320                 }
2321         }
2322
2323         /* If a unit attention condition exists, only INQUIRY and
2324          * REQUEST SENSE commands are allowed; anything else must fail. */
2325         if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
2326                         fsg->cmnd[0] != INQUIRY &&
2327                         fsg->cmnd[0] != REQUEST_SENSE) {
2328                 curlun->sense_data = curlun->unit_attention_data;
2329                 curlun->unit_attention_data = SS_NO_SENSE;
2330                 return -EINVAL;
2331         }
2332
2333         /* Check that only command bytes listed in the mask are non-zero */
2334         fsg->cmnd[1] &= 0x1f;                   // Mask away the LUN
2335         for (i = 1; i < cmnd_size; ++i) {
2336                 if (fsg->cmnd[i] && !(mask & (1 << i))) {
2337                         if (curlun)
2338                                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2339                         return -EINVAL;
2340                 }
2341         }
2342
2343         /* If the medium isn't mounted and the command needs to access
2344          * it, return an error. */
2345         if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
2346                 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2347                 return -EINVAL;
2348         }
2349
2350         return 0;
2351 }
2352
2353
2354 static int do_scsi_command(struct fsg_dev *fsg)
2355 {
2356         struct fsg_buffhd       *bh;
2357         int                     rc;
2358         int                     reply = -EINVAL;
2359         int                     i;
2360         static char             unknown[16];
2361
2362         dump_cdb(fsg);
2363
2364         /* Wait for the next buffer to become available for data or status */
2365         bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill;
2366         while (bh->state != BUF_STATE_EMPTY) {
2367                 rc = sleep_thread(fsg);
2368                 if (rc)
2369                         return rc;
2370         }
2371         fsg->phase_error = 0;
2372         fsg->short_packet_received = 0;
2373
2374         down_read(&fsg->filesem);       // We're using the backing file
2375         switch (fsg->cmnd[0]) {
2376
2377         case INQUIRY:
2378                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2379                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2380                                 (1<<4), 0,
2381                                 "INQUIRY")) == 0)
2382                         reply = do_inquiry(fsg, bh);
2383                 break;
2384
2385         case MODE_SELECT:
2386                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2387                 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2388                                 (1<<1) | (1<<4), 0,
2389                                 "MODE SELECT(6)")) == 0)
2390                         reply = do_mode_select(fsg, bh);
2391                 break;
2392
2393         case MODE_SELECT_10:
2394                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2395                 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2396                                 (1<<1) | (3<<7), 0,
2397                                 "MODE SELECT(10)")) == 0)
2398                         reply = do_mode_select(fsg, bh);
2399                 break;
2400
2401         case MODE_SENSE:
2402                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2403                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2404                                 (1<<1) | (1<<2) | (1<<4), 0,
2405                                 "MODE SENSE(6)")) == 0)
2406                         reply = do_mode_sense(fsg, bh);
2407                 break;
2408
2409         case MODE_SENSE_10:
2410                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2411                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2412                                 (1<<1) | (1<<2) | (3<<7), 0,
2413                                 "MODE SENSE(10)")) == 0)
2414                         reply = do_mode_sense(fsg, bh);
2415                 break;
2416
2417         case ALLOW_MEDIUM_REMOVAL:
2418                 fsg->data_size_from_cmnd = 0;
2419                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2420                                 (1<<4), 0,
2421                                 "PREVENT-ALLOW MEDIUM REMOVAL")) == 0)
2422                         reply = do_prevent_allow(fsg);
2423                 break;
2424
2425         case READ_6:
2426                 i = fsg->cmnd[4];
2427                 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << fsg->curlun->blkbits;
2428                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2429                                 (7<<1) | (1<<4), 1,
2430                                 "READ(6)")) == 0)
2431                         reply = do_read(fsg);
2432                 break;
2433
2434         case READ_10:
2435                 fsg->data_size_from_cmnd =
2436                                 get_unaligned_be16(&fsg->cmnd[7]) << fsg->curlun->blkbits;
2437                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2438                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2439                                 "READ(10)")) == 0)
2440                         reply = do_read(fsg);
2441                 break;
2442
2443         case READ_12:
2444                 fsg->data_size_from_cmnd =
2445                                 get_unaligned_be32(&fsg->cmnd[6]) << fsg->curlun->blkbits;
2446                 if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
2447                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2448                                 "READ(12)")) == 0)
2449                         reply = do_read(fsg);
2450                 break;
2451
2452         case READ_CAPACITY:
2453                 fsg->data_size_from_cmnd = 8;
2454                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2455                                 (0xf<<2) | (1<<8), 1,
2456                                 "READ CAPACITY")) == 0)
2457                         reply = do_read_capacity(fsg, bh);
2458                 break;
2459
2460         case READ_HEADER:
2461                 if (!mod_data.cdrom)
2462                         goto unknown_cmnd;
2463                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2464                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2465                                 (3<<7) | (0x1f<<1), 1,
2466                                 "READ HEADER")) == 0)
2467                         reply = do_read_header(fsg, bh);
2468                 break;
2469
2470         case READ_TOC:
2471                 if (!mod_data.cdrom)
2472                         goto unknown_cmnd;
2473                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2474                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2475                                 (7<<6) | (1<<1), 1,
2476                                 "READ TOC")) == 0)
2477                         reply = do_read_toc(fsg, bh);
2478                 break;
2479
2480         case READ_FORMAT_CAPACITIES:
2481                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2482                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2483                                 (3<<7), 1,
2484                                 "READ FORMAT CAPACITIES")) == 0)
2485                         reply = do_read_format_capacities(fsg, bh);
2486                 break;
2487
2488         case REQUEST_SENSE:
2489                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2490                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2491                                 (1<<4), 0,
2492                                 "REQUEST SENSE")) == 0)
2493                         reply = do_request_sense(fsg, bh);
2494                 break;
2495
2496         case START_STOP:
2497                 fsg->data_size_from_cmnd = 0;
2498                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2499                                 (1<<1) | (1<<4), 0,
2500                                 "START-STOP UNIT")) == 0)
2501                         reply = do_start_stop(fsg);
2502                 break;
2503
2504         case SYNCHRONIZE_CACHE:
2505                 fsg->data_size_from_cmnd = 0;
2506                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2507                                 (0xf<<2) | (3<<7), 1,
2508                                 "SYNCHRONIZE CACHE")) == 0)
2509                         reply = do_synchronize_cache(fsg);
2510                 break;
2511
2512         case TEST_UNIT_READY:
2513                 fsg->data_size_from_cmnd = 0;
2514                 reply = check_command(fsg, 6, DATA_DIR_NONE,
2515                                 0, 1,
2516                                 "TEST UNIT READY");
2517                 break;
2518
2519         /* Although optional, this command is used by MS-Windows.  We
2520          * support a minimal version: BytChk must be 0. */
2521         case VERIFY:
2522                 fsg->data_size_from_cmnd = 0;
2523                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2524                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2525                                 "VERIFY")) == 0)
2526                         reply = do_verify(fsg);
2527                 break;
2528
2529         case WRITE_6:
2530                 i = fsg->cmnd[4];
2531                 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << fsg->curlun->blkbits;
2532                 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2533                                 (7<<1) | (1<<4), 1,
2534                                 "WRITE(6)")) == 0)
2535                         reply = do_write(fsg);
2536                 break;
2537
2538         case WRITE_10:
2539                 fsg->data_size_from_cmnd =
2540                                 get_unaligned_be16(&fsg->cmnd[7]) << fsg->curlun->blkbits;
2541                 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2542                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2543                                 "WRITE(10)")) == 0)
2544                         reply = do_write(fsg);
2545                 break;
2546
2547         case WRITE_12:
2548                 fsg->data_size_from_cmnd =
2549                                 get_unaligned_be32(&fsg->cmnd[6]) << fsg->curlun->blkbits;
2550                 if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
2551                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2552                                 "WRITE(12)")) == 0)
2553                         reply = do_write(fsg);
2554                 break;
2555
2556         /* Some mandatory commands that we recognize but don't implement.
2557          * They don't mean much in this setting.  It's left as an exercise
2558          * for anyone interested to implement RESERVE and RELEASE in terms
2559          * of Posix locks. */
2560         case FORMAT_UNIT:
2561         case RELEASE:
2562         case RESERVE:
2563         case SEND_DIAGNOSTIC:
2564                 // Fall through
2565
2566         default:
2567  unknown_cmnd:
2568                 fsg->data_size_from_cmnd = 0;
2569                 sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]);
2570                 if ((reply = check_command(fsg, fsg->cmnd_size,
2571                                 DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) {
2572                         fsg->curlun->sense_data = SS_INVALID_COMMAND;
2573                         reply = -EINVAL;
2574                 }
2575                 break;
2576         }
2577         up_read(&fsg->filesem);
2578
2579         if (reply == -EINTR || signal_pending(current))
2580                 return -EINTR;
2581
2582         /* Set up the single reply buffer for finish_reply() */
2583         if (reply == -EINVAL)
2584                 reply = 0;              // Error reply length
2585         if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
2586                 reply = min((u32) reply, fsg->data_size_from_cmnd);
2587                 bh->inreq->length = reply;
2588                 bh->state = BUF_STATE_FULL;
2589                 fsg->residue -= reply;
2590         }                               // Otherwise it's already set
2591
2592         return 0;
2593 }
2594
2595
2596 /*-------------------------------------------------------------------------*/
2597
2598 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2599 {
2600         struct usb_request              *req = bh->outreq;
2601         struct fsg_bulk_cb_wrap *cbw = req->buf;
2602
2603         /* Was this a real packet?  Should it be ignored? */
2604         if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2605                 return -EINVAL;
2606
2607         /* Is the CBW valid? */
2608         if (req->actual != USB_BULK_CB_WRAP_LEN ||
2609                         cbw->Signature != cpu_to_le32(
2610                                 USB_BULK_CB_SIG)) {
2611                 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2612                                 req->actual,
2613                                 le32_to_cpu(cbw->Signature));
2614
2615                 /* The Bulk-only spec says we MUST stall the IN endpoint
2616                  * (6.6.1), so it's unavoidable.  It also says we must
2617                  * retain this state until the next reset, but there's
2618                  * no way to tell the controller driver it should ignore
2619                  * Clear-Feature(HALT) requests.
2620                  *
2621                  * We aren't required to halt the OUT endpoint; instead
2622                  * we can simply accept and discard any data received
2623                  * until the next reset. */
2624                 wedge_bulk_in_endpoint(fsg);
2625                 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2626                 return -EINVAL;
2627         }
2628
2629         /* Is the CBW meaningful? */
2630         if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2631                         cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2632                 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2633                                 "cmdlen %u\n",
2634                                 cbw->Lun, cbw->Flags, cbw->Length);
2635
2636                 /* We can do anything we want here, so let's stall the
2637                  * bulk pipes if we are allowed to. */
2638                 if (mod_data.can_stall) {
2639                         fsg_set_halt(fsg, fsg->bulk_out);
2640                         halt_bulk_in_endpoint(fsg);
2641                 }
2642                 return -EINVAL;
2643         }
2644
2645         /* Save the command for later */
2646         fsg->cmnd_size = cbw->Length;
2647         memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size);
2648         if (cbw->Flags & USB_BULK_IN_FLAG)
2649                 fsg->data_dir = DATA_DIR_TO_HOST;
2650         else
2651                 fsg->data_dir = DATA_DIR_FROM_HOST;
2652         fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
2653         if (fsg->data_size == 0)
2654                 fsg->data_dir = DATA_DIR_NONE;
2655         fsg->lun = cbw->Lun;
2656         fsg->tag = cbw->Tag;
2657         return 0;
2658 }
2659
2660
2661 static int get_next_command(struct fsg_dev *fsg)
2662 {
2663         struct fsg_buffhd       *bh;
2664         int                     rc = 0;
2665
2666         if (transport_is_bbb()) {
2667
2668                 /* Wait for the next buffer to become available */
2669                 bh = fsg->next_buffhd_to_fill;
2670                 while (bh->state != BUF_STATE_EMPTY) {
2671                         rc = sleep_thread(fsg);
2672                         if (rc)
2673                                 return rc;
2674                 }
2675
2676                 /* Queue a request to read a Bulk-only CBW */
2677                 set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
2678                 start_transfer(fsg, fsg->bulk_out, bh->outreq,
2679                                 &bh->outreq_busy, &bh->state);
2680
2681                 /* We will drain the buffer in software, which means we
2682                  * can reuse it for the next filling.  No need to advance
2683                  * next_buffhd_to_fill. */
2684
2685                 /* Wait for the CBW to arrive */
2686                 while (bh->state != BUF_STATE_FULL) {
2687                         rc = sleep_thread(fsg);
2688                         if (rc)
2689                                 return rc;
2690                 }
2691                 smp_rmb();
2692                 rc = received_cbw(fsg, bh);
2693                 bh->state = BUF_STATE_EMPTY;
2694
2695         } else {                // USB_PR_CB or USB_PR_CBI
2696
2697                 /* Wait for the next command to arrive */
2698                 while (fsg->cbbuf_cmnd_size == 0) {
2699                         rc = sleep_thread(fsg);
2700                         if (rc)
2701                                 return rc;
2702                 }
2703
2704                 /* Is the previous status interrupt request still busy?
2705                  * The host is allowed to skip reading the status,
2706                  * so we must cancel it. */
2707                 if (fsg->intreq_busy)
2708                         usb_ep_dequeue(fsg->intr_in, fsg->intreq);
2709
2710                 /* Copy the command and mark the buffer empty */
2711                 fsg->data_dir = DATA_DIR_UNKNOWN;
2712                 spin_lock_irq(&fsg->lock);
2713                 fsg->cmnd_size = fsg->cbbuf_cmnd_size;
2714                 memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size);
2715                 fsg->cbbuf_cmnd_size = 0;
2716                 spin_unlock_irq(&fsg->lock);
2717         }
2718         return rc;
2719 }
2720
2721
2722 /*-------------------------------------------------------------------------*/
2723
2724 static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
2725                 const struct usb_endpoint_descriptor *d)
2726 {
2727         int     rc;
2728
2729         ep->driver_data = fsg;
2730         ep->desc = d;
2731         rc = usb_ep_enable(ep);
2732         if (rc)
2733                 ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
2734         return rc;
2735 }
2736
2737 static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
2738                 struct usb_request **preq)
2739 {
2740         *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2741         if (*preq)
2742                 return 0;
2743         ERROR(fsg, "can't allocate request for %s\n", ep->name);
2744         return -ENOMEM;
2745 }
2746
2747 /*
2748  * Reset interface setting and re-init endpoint state (toggle etc).
2749  * Call with altsetting < 0 to disable the interface.  The only other
2750  * available altsetting is 0, which enables the interface.
2751  */
2752 static int do_set_interface(struct fsg_dev *fsg, int altsetting)
2753 {
2754         int     rc = 0;
2755         int     i;
2756         const struct usb_endpoint_descriptor    *d;
2757
2758         if (fsg->running)
2759                 DBG(fsg, "reset interface\n");
2760
2761 reset:
2762         /* Deallocate the requests */
2763         for (i = 0; i < fsg_num_buffers; ++i) {
2764                 struct fsg_buffhd *bh = &fsg->buffhds[i];
2765
2766                 if (bh->inreq) {
2767                         usb_ep_free_request(fsg->bulk_in, bh->inreq);
2768                         bh->inreq = NULL;
2769                 }
2770                 if (bh->outreq) {
2771                         usb_ep_free_request(fsg->bulk_out, bh->outreq);
2772                         bh->outreq = NULL;
2773                 }
2774         }
2775         if (fsg->intreq) {
2776                 usb_ep_free_request(fsg->intr_in, fsg->intreq);
2777                 fsg->intreq = NULL;
2778         }
2779
2780         /* Disable the endpoints */
2781         if (fsg->bulk_in_enabled) {
2782                 usb_ep_disable(fsg->bulk_in);
2783                 fsg->bulk_in_enabled = 0;
2784         }
2785         if (fsg->bulk_out_enabled) {
2786                 usb_ep_disable(fsg->bulk_out);
2787                 fsg->bulk_out_enabled = 0;
2788         }
2789         if (fsg->intr_in_enabled) {
2790                 usb_ep_disable(fsg->intr_in);
2791                 fsg->intr_in_enabled = 0;
2792         }
2793
2794         fsg->running = 0;
2795         if (altsetting < 0 || rc != 0)
2796                 return rc;
2797
2798         DBG(fsg, "set interface %d\n", altsetting);
2799
2800         /* Enable the endpoints */
2801         d = fsg_ep_desc(fsg->gadget,
2802                         &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc,
2803                         &fsg_ss_bulk_in_desc);
2804         if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
2805                 goto reset;
2806         fsg->bulk_in_enabled = 1;
2807
2808         d = fsg_ep_desc(fsg->gadget,
2809                         &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc,
2810                         &fsg_ss_bulk_out_desc);
2811         if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0)
2812                 goto reset;
2813         fsg->bulk_out_enabled = 1;
2814         fsg->bulk_out_maxpacket = usb_endpoint_maxp(d);
2815         clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2816
2817         if (transport_is_cbi()) {
2818                 d = fsg_ep_desc(fsg->gadget,
2819                                 &fsg_fs_intr_in_desc, &fsg_hs_intr_in_desc,
2820                                 &fsg_ss_intr_in_desc);
2821                 if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0)
2822                         goto reset;
2823                 fsg->intr_in_enabled = 1;
2824         }
2825
2826         /* Allocate the requests */
2827         for (i = 0; i < fsg_num_buffers; ++i) {
2828                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
2829
2830                 if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0)
2831                         goto reset;
2832                 if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0)
2833                         goto reset;
2834                 bh->inreq->buf = bh->outreq->buf = bh->buf;
2835                 bh->inreq->context = bh->outreq->context = bh;
2836                 bh->inreq->complete = bulk_in_complete;
2837                 bh->outreq->complete = bulk_out_complete;
2838         }
2839         if (transport_is_cbi()) {
2840                 if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0)
2841                         goto reset;
2842                 fsg->intreq->complete = intr_in_complete;
2843         }
2844
2845         fsg->running = 1;
2846         for (i = 0; i < fsg->nluns; ++i)
2847                 fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2848         return rc;
2849 }
2850
2851
2852 /*
2853  * Change our operational configuration.  This code must agree with the code
2854  * that returns config descriptors, and with interface altsetting code.
2855  *
2856  * It's also responsible for power management interactions.  Some
2857  * configurations might not work with our current power sources.
2858  * For now we just assume the gadget is always self-powered.
2859  */
2860 static int do_set_config(struct fsg_dev *fsg, u8 new_config)
2861 {
2862         int     rc = 0;
2863
2864         /* Disable the single interface */
2865         if (fsg->config != 0) {
2866                 DBG(fsg, "reset config\n");
2867                 fsg->config = 0;
2868                 rc = do_set_interface(fsg, -1);
2869         }
2870
2871         /* Enable the interface */
2872         if (new_config != 0) {
2873                 fsg->config = new_config;
2874                 if ((rc = do_set_interface(fsg, 0)) != 0)
2875                         fsg->config = 0;        // Reset on errors
2876                 else
2877                         INFO(fsg, "%s config #%d\n",
2878                              usb_speed_string(fsg->gadget->speed),
2879                              fsg->config);
2880         }
2881         return rc;
2882 }
2883
2884
2885 /*-------------------------------------------------------------------------*/
2886
2887 static void handle_exception(struct fsg_dev *fsg)
2888 {
2889         siginfo_t               info;
2890         int                     sig;
2891         int                     i;
2892         int                     num_active;
2893         struct fsg_buffhd       *bh;
2894         enum fsg_state          old_state;
2895         u8                      new_config;
2896         struct fsg_lun          *curlun;
2897         unsigned int            exception_req_tag;
2898         int                     rc;
2899
2900         /* Clear the existing signals.  Anything but SIGUSR1 is converted
2901          * into a high-priority EXIT exception. */
2902         for (;;) {
2903                 sig = dequeue_signal_lock(current, &current->blocked, &info);
2904                 if (!sig)
2905                         break;
2906                 if (sig != SIGUSR1) {
2907                         if (fsg->state < FSG_STATE_EXIT)
2908                                 DBG(fsg, "Main thread exiting on signal\n");
2909                         raise_exception(fsg, FSG_STATE_EXIT);
2910                 }
2911         }
2912
2913         /* Cancel all the pending transfers */
2914         if (fsg->intreq_busy)
2915                 usb_ep_dequeue(fsg->intr_in, fsg->intreq);
2916         for (i = 0; i < fsg_num_buffers; ++i) {
2917                 bh = &fsg->buffhds[i];
2918                 if (bh->inreq_busy)
2919                         usb_ep_dequeue(fsg->bulk_in, bh->inreq);
2920                 if (bh->outreq_busy)
2921                         usb_ep_dequeue(fsg->bulk_out, bh->outreq);
2922         }
2923
2924         /* Wait until everything is idle */
2925         for (;;) {
2926                 num_active = fsg->intreq_busy;
2927                 for (i = 0; i < fsg_num_buffers; ++i) {
2928                         bh = &fsg->buffhds[i];
2929                         num_active += bh->inreq_busy + bh->outreq_busy;
2930                 }
2931                 if (num_active == 0)
2932                         break;
2933                 if (sleep_thread(fsg))
2934                         return;
2935         }
2936
2937         /* Clear out the controller's fifos */
2938         if (fsg->bulk_in_enabled)
2939                 usb_ep_fifo_flush(fsg->bulk_in);
2940         if (fsg->bulk_out_enabled)
2941                 usb_ep_fifo_flush(fsg->bulk_out);
2942         if (fsg->intr_in_enabled)
2943                 usb_ep_fifo_flush(fsg->intr_in);
2944
2945         /* Reset the I/O buffer states and pointers, the SCSI
2946          * state, and the exception.  Then invoke the handler. */
2947         spin_lock_irq(&fsg->lock);
2948
2949         for (i = 0; i < fsg_num_buffers; ++i) {
2950                 bh = &fsg->buffhds[i];
2951                 bh->state = BUF_STATE_EMPTY;
2952         }
2953         fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain =
2954                         &fsg->buffhds[0];
2955
2956         exception_req_tag = fsg->exception_req_tag;
2957         new_config = fsg->new_config;
2958         old_state = fsg->state;
2959
2960         if (old_state == FSG_STATE_ABORT_BULK_OUT)
2961                 fsg->state = FSG_STATE_STATUS_PHASE;
2962         else {
2963                 for (i = 0; i < fsg->nluns; ++i) {
2964                         curlun = &fsg->luns[i];
2965                         curlun->prevent_medium_removal = 0;
2966                         curlun->sense_data = curlun->unit_attention_data =
2967                                         SS_NO_SENSE;
2968                         curlun->sense_data_info = 0;
2969                         curlun->info_valid = 0;
2970                 }
2971                 fsg->state = FSG_STATE_IDLE;
2972         }
2973         spin_unlock_irq(&fsg->lock);
2974
2975         /* Carry out any extra actions required for the exception */
2976         switch (old_state) {
2977         default:
2978                 break;
2979
2980         case FSG_STATE_ABORT_BULK_OUT:
2981                 send_status(fsg);
2982                 spin_lock_irq(&fsg->lock);
2983                 if (fsg->state == FSG_STATE_STATUS_PHASE)
2984                         fsg->state = FSG_STATE_IDLE;
2985                 spin_unlock_irq(&fsg->lock);
2986                 break;
2987
2988         case FSG_STATE_RESET:
2989                 /* In case we were forced against our will to halt a
2990                  * bulk endpoint, clear the halt now.  (The SuperH UDC
2991                  * requires this.) */
2992                 if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2993                         usb_ep_clear_halt(fsg->bulk_in);
2994
2995                 if (transport_is_bbb()) {
2996                         if (fsg->ep0_req_tag == exception_req_tag)
2997                                 ep0_queue(fsg); // Complete the status stage
2998
2999                 } else if (transport_is_cbi())
3000                         send_status(fsg);       // Status by interrupt pipe
3001
3002                 /* Technically this should go here, but it would only be
3003                  * a waste of time.  Ditto for the INTERFACE_CHANGE and
3004                  * CONFIG_CHANGE cases. */
3005                 // for (i = 0; i < fsg->nluns; ++i)
3006                 //      fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3007                 break;
3008
3009         case FSG_STATE_INTERFACE_CHANGE:
3010                 rc = do_set_interface(fsg, 0);
3011                 if (fsg->ep0_req_tag != exception_req_tag)
3012                         break;
3013                 if (rc != 0)                    // STALL on errors
3014                         fsg_set_halt(fsg, fsg->ep0);
3015                 else                            // Complete the status stage
3016                         ep0_queue(fsg);
3017                 break;
3018
3019         case FSG_STATE_CONFIG_CHANGE:
3020                 rc = do_set_config(fsg, new_config);
3021                 if (fsg->ep0_req_tag != exception_req_tag)
3022                         break;
3023                 if (rc != 0)                    // STALL on errors
3024                         fsg_set_halt(fsg, fsg->ep0);
3025                 else                            // Complete the status stage
3026                         ep0_queue(fsg);
3027                 break;
3028
3029         case FSG_STATE_DISCONNECT:
3030                 for (i = 0; i < fsg->nluns; ++i)
3031                         fsg_lun_fsync_sub(fsg->luns + i);
3032                 do_set_config(fsg, 0);          // Unconfigured state
3033                 break;
3034
3035         case FSG_STATE_EXIT:
3036         case FSG_STATE_TERMINATED:
3037                 do_set_config(fsg, 0);                  // Free resources
3038                 spin_lock_irq(&fsg->lock);
3039                 fsg->state = FSG_STATE_TERMINATED;      // Stop the thread
3040                 spin_unlock_irq(&fsg->lock);
3041                 break;
3042         }
3043 }
3044
3045
3046 /*-------------------------------------------------------------------------*/
3047
3048 static int fsg_main_thread(void *fsg_)
3049 {
3050         struct fsg_dev          *fsg = fsg_;
3051
3052         /* Allow the thread to be killed by a signal, but set the signal mask
3053          * to block everything but INT, TERM, KILL, and USR1. */
3054         allow_signal(SIGINT);
3055         allow_signal(SIGTERM);
3056         allow_signal(SIGKILL);
3057         allow_signal(SIGUSR1);
3058
3059         /* Allow the thread to be frozen */
3060         set_freezable();
3061
3062         /* Arrange for userspace references to be interpreted as kernel
3063          * pointers.  That way we can pass a kernel pointer to a routine
3064          * that expects a __user pointer and it will work okay. */
3065         set_fs(get_ds());
3066
3067         /* The main loop */
3068         while (fsg->state != FSG_STATE_TERMINATED) {
3069                 if (exception_in_progress(fsg) || signal_pending(current)) {
3070                         handle_exception(fsg);
3071                         continue;
3072                 }
3073
3074                 if (!fsg->running) {
3075                         sleep_thread(fsg);
3076                         continue;
3077                 }
3078
3079                 if (get_next_command(fsg))
3080                         continue;
3081
3082                 spin_lock_irq(&fsg->lock);
3083                 if (!exception_in_progress(fsg))
3084                         fsg->state = FSG_STATE_DATA_PHASE;
3085                 spin_unlock_irq(&fsg->lock);
3086
3087                 if (do_scsi_command(fsg) || finish_reply(fsg))
3088                         continue;
3089
3090                 spin_lock_irq(&fsg->lock);
3091                 if (!exception_in_progress(fsg))
3092                         fsg->state = FSG_STATE_STATUS_PHASE;
3093                 spin_unlock_irq(&fsg->lock);
3094
3095                 if (send_status(fsg))
3096                         continue;
3097
3098                 spin_lock_irq(&fsg->lock);
3099                 if (!exception_in_progress(fsg))
3100                         fsg->state = FSG_STATE_IDLE;
3101                 spin_unlock_irq(&fsg->lock);
3102                 }
3103
3104         spin_lock_irq(&fsg->lock);
3105         fsg->thread_task = NULL;
3106         spin_unlock_irq(&fsg->lock);
3107
3108         /* If we are exiting because of a signal, unregister the
3109          * gadget driver. */
3110         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
3111                 usb_gadget_unregister_driver(&fsg_driver);
3112
3113         /* Let the unbind and cleanup routines know the thread has exited */
3114         complete_and_exit(&fsg->thread_notifier, 0);
3115 }
3116
3117
3118 /*-------------------------------------------------------------------------*/
3119
3120
3121 /* The write permissions and store_xxx pointers are set in fsg_bind() */
3122 static DEVICE_ATTR(ro, 0444, fsg_show_ro, NULL);
3123 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, NULL);
3124 static DEVICE_ATTR(file, 0444, fsg_show_file, NULL);
3125
3126
3127 /*-------------------------------------------------------------------------*/
3128
3129 static void fsg_release(struct kref *ref)
3130 {
3131         struct fsg_dev  *fsg = container_of(ref, struct fsg_dev, ref);
3132
3133         kfree(fsg->luns);
3134         kfree(fsg);
3135 }
3136
3137 static void lun_release(struct device *dev)
3138 {
3139         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
3140         struct fsg_dev          *fsg =
3141                 container_of(filesem, struct fsg_dev, filesem);
3142
3143         kref_put(&fsg->ref, fsg_release);
3144 }
3145
3146 static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
3147 {
3148         struct fsg_dev          *fsg = get_gadget_data(gadget);
3149         int                     i;
3150         struct fsg_lun          *curlun;
3151         struct usb_request      *req = fsg->ep0req;
3152
3153         DBG(fsg, "unbind\n");
3154         clear_bit(REGISTERED, &fsg->atomic_bitflags);
3155
3156         /* If the thread isn't already dead, tell it to exit now */
3157         if (fsg->state != FSG_STATE_TERMINATED) {
3158                 raise_exception(fsg, FSG_STATE_EXIT);
3159                 wait_for_completion(&fsg->thread_notifier);
3160
3161                 /* The cleanup routine waits for this completion also */
3162                 complete(&fsg->thread_notifier);
3163         }
3164
3165         /* Unregister the sysfs attribute files and the LUNs */
3166         for (i = 0; i < fsg->nluns; ++i) {
3167                 curlun = &fsg->luns[i];
3168                 if (curlun->registered) {
3169                         device_remove_file(&curlun->dev, &dev_attr_nofua);
3170                         device_remove_file(&curlun->dev, &dev_attr_ro);
3171                         device_remove_file(&curlun->dev, &dev_attr_file);
3172                         fsg_lun_close(curlun);
3173                         device_unregister(&curlun->dev);
3174                         curlun->registered = 0;
3175                 }
3176         }
3177
3178         /* Free the data buffers */
3179         for (i = 0; i < fsg_num_buffers; ++i)
3180                 kfree(fsg->buffhds[i].buf);
3181
3182         /* Free the request and buffer for endpoint 0 */
3183         if (req) {
3184                 kfree(req->buf);
3185                 usb_ep_free_request(fsg->ep0, req);
3186         }
3187
3188         set_gadget_data(gadget, NULL);
3189 }
3190
3191
3192 static int __init check_parameters(struct fsg_dev *fsg)
3193 {
3194         int     prot;
3195         int     gcnum;
3196
3197         /* Store the default values */
3198         mod_data.transport_type = USB_PR_BULK;
3199         mod_data.transport_name = "Bulk-only";
3200         mod_data.protocol_type = USB_SC_SCSI;
3201         mod_data.protocol_name = "Transparent SCSI";
3202
3203         /* Some peripheral controllers are known not to be able to
3204          * halt bulk endpoints correctly.  If one of them is present,
3205          * disable stalls.
3206          */
3207         if (gadget_is_at91(fsg->gadget))
3208                 mod_data.can_stall = 0;
3209
3210         if (mod_data.release == 0xffff) {       // Parameter wasn't set
3211                 gcnum = usb_gadget_controller_number(fsg->gadget);
3212                 if (gcnum >= 0)
3213                         mod_data.release = 0x0300 + gcnum;
3214                 else {
3215                         WARNING(fsg, "controller '%s' not recognized\n",
3216                                 fsg->gadget->name);
3217                         mod_data.release = 0x0399;
3218                 }
3219         }
3220
3221         prot = simple_strtol(mod_data.protocol_parm, NULL, 0);
3222
3223 #ifdef CONFIG_USB_FILE_STORAGE_TEST
3224         if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) {
3225                 ;               // Use default setting
3226         } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) {
3227                 mod_data.transport_type = USB_PR_CB;
3228                 mod_data.transport_name = "Control-Bulk";
3229         } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) {
3230                 mod_data.transport_type = USB_PR_CBI;
3231                 mod_data.transport_name = "Control-Bulk-Interrupt";
3232         } else {
3233                 ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm);
3234                 return -EINVAL;
3235         }
3236
3237         if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 ||
3238                         prot == USB_SC_SCSI) {
3239                 ;               // Use default setting
3240         } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 ||
3241                         prot == USB_SC_RBC) {
3242                 mod_data.protocol_type = USB_SC_RBC;
3243                 mod_data.protocol_name = "RBC";
3244         } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 ||
3245                         strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 ||
3246                         prot == USB_SC_8020) {
3247                 mod_data.protocol_type = USB_SC_8020;
3248                 mod_data.protocol_name = "8020i (ATAPI)";
3249         } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 ||
3250                         prot == USB_SC_QIC) {
3251                 mod_data.protocol_type = USB_SC_QIC;
3252                 mod_data.protocol_name = "QIC-157";
3253         } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 ||
3254                         prot == USB_SC_UFI) {
3255                 mod_data.protocol_type = USB_SC_UFI;
3256                 mod_data.protocol_name = "UFI";
3257         } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 ||
3258                         prot == USB_SC_8070) {
3259                 mod_data.protocol_type = USB_SC_8070;
3260                 mod_data.protocol_name = "8070i";
3261         } else {
3262                 ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm);
3263                 return -EINVAL;
3264         }
3265
3266         mod_data.buflen &= PAGE_CACHE_MASK;
3267         if (mod_data.buflen <= 0) {
3268                 ERROR(fsg, "invalid buflen\n");
3269                 return -ETOOSMALL;
3270         }
3271
3272 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
3273
3274         /* Serial string handling.
3275          * On a real device, the serial string would be loaded
3276          * from permanent storage. */
3277         if (mod_data.serial) {
3278                 const char *ch;
3279                 unsigned len = 0;
3280
3281                 /* Sanity check :
3282                  * The CB[I] specification limits the serial string to
3283                  * 12 uppercase hexadecimal characters.
3284                  * BBB need at least 12 uppercase hexadecimal characters,
3285                  * with a maximum of 126. */
3286                 for (ch = mod_data.serial; *ch; ++ch) {
3287                         ++len;
3288                         if ((*ch < '0' || *ch > '9') &&
3289                             (*ch < 'A' || *ch > 'F')) { /* not uppercase hex */
3290                                 WARNING(fsg,
3291                                         "Invalid serial string character: %c\n",
3292                                         *ch);
3293                                 goto no_serial;
3294                         }
3295                 }
3296                 if (len > 126 ||
3297                     (mod_data.transport_type == USB_PR_BULK && len < 12) ||
3298                     (mod_data.transport_type != USB_PR_BULK && len > 12)) {
3299                         WARNING(fsg, "Invalid serial string length!\n");
3300                         goto no_serial;
3301                 }
3302                 fsg_strings[FSG_STRING_SERIAL - 1].s = mod_data.serial;
3303         } else {
3304                 WARNING(fsg, "No serial-number string provided!\n");
3305  no_serial:
3306                 device_desc.iSerialNumber = 0;
3307         }
3308
3309         return 0;
3310 }
3311
3312
3313 static int __init fsg_bind(struct usb_gadget *gadget)
3314 {
3315         struct fsg_dev          *fsg = the_fsg;
3316         int                     rc;
3317         int                     i;
3318         struct fsg_lun          *curlun;
3319         struct usb_ep           *ep;
3320         struct usb_request      *req;
3321         char                    *pathbuf, *p;
3322
3323         fsg->gadget = gadget;
3324         set_gadget_data(gadget, fsg);
3325         fsg->ep0 = gadget->ep0;
3326         fsg->ep0->driver_data = fsg;
3327
3328         if ((rc = check_parameters(fsg)) != 0)
3329                 goto out;
3330
3331         if (mod_data.removable) {       // Enable the store_xxx attributes
3332                 dev_attr_file.attr.mode = 0644;
3333                 dev_attr_file.store = fsg_store_file;
3334                 if (!mod_data.cdrom) {
3335                         dev_attr_ro.attr.mode = 0644;
3336                         dev_attr_ro.store = fsg_store_ro;
3337                 }
3338         }
3339
3340         /* Only for removable media? */
3341         dev_attr_nofua.attr.mode = 0644;
3342         dev_attr_nofua.store = fsg_store_nofua;
3343
3344         /* Find out how many LUNs there should be */
3345         i = mod_data.nluns;
3346         if (i == 0)
3347                 i = max(mod_data.num_filenames, 1u);
3348         if (i > FSG_MAX_LUNS) {
3349                 ERROR(fsg, "invalid number of LUNs: %d\n", i);
3350                 rc = -EINVAL;
3351                 goto out;
3352         }
3353
3354         /* Create the LUNs, open their backing files, and register the
3355          * LUN devices in sysfs. */
3356         fsg->luns = kzalloc(i * sizeof(struct fsg_lun), GFP_KERNEL);
3357         if (!fsg->luns) {
3358                 rc = -ENOMEM;
3359                 goto out;
3360         }
3361         fsg->nluns = i;
3362
3363         for (i = 0; i < fsg->nluns; ++i) {
3364                 curlun = &fsg->luns[i];
3365                 curlun->cdrom = !!mod_data.cdrom;
3366                 curlun->ro = mod_data.cdrom || mod_data.ro[i];
3367                 curlun->initially_ro = curlun->ro;
3368                 curlun->removable = mod_data.removable;
3369                 curlun->nofua = mod_data.nofua[i];
3370                 curlun->dev.release = lun_release;
3371                 curlun->dev.parent = &gadget->dev;
3372                 curlun->dev.driver = &fsg_driver.driver;
3373                 dev_set_drvdata(&curlun->dev, &fsg->filesem);
3374                 dev_set_name(&curlun->dev,"%s-lun%d",
3375                              dev_name(&gadget->dev), i);
3376
3377                 kref_get(&fsg->ref);
3378                 rc = device_register(&curlun->dev);
3379                 if (rc) {
3380                         INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
3381                         put_device(&curlun->dev);
3382                         goto out;
3383                 }
3384                 curlun->registered = 1;
3385
3386                 rc = device_create_file(&curlun->dev, &dev_attr_ro);
3387                 if (rc)
3388                         goto out;
3389                 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
3390                 if (rc)
3391                         goto out;
3392                 rc = device_create_file(&curlun->dev, &dev_attr_file);
3393                 if (rc)
3394                         goto out;
3395
3396                 if (mod_data.file[i] && *mod_data.file[i]) {
3397                         rc = fsg_lun_open(curlun, mod_data.file[i]);
3398                         if (rc)
3399                                 goto out;
3400                 } else if (!mod_data.removable) {
3401                         ERROR(fsg, "no file given for LUN%d\n", i);
3402                         rc = -EINVAL;
3403                         goto out;
3404                 }
3405         }
3406
3407         /* Find all the endpoints we will use */
3408         usb_ep_autoconfig_reset(gadget);
3409         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3410         if (!ep)
3411                 goto autoconf_fail;
3412         ep->driver_data = fsg;          // claim the endpoint
3413         fsg->bulk_in = ep;
3414
3415         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3416         if (!ep)
3417                 goto autoconf_fail;
3418         ep->driver_data = fsg;          // claim the endpoint
3419         fsg->bulk_out = ep;
3420
3421         if (transport_is_cbi()) {
3422                 ep = usb_ep_autoconfig(gadget, &fsg_fs_intr_in_desc);
3423                 if (!ep)
3424                         goto autoconf_fail;
3425                 ep->driver_data = fsg;          // claim the endpoint
3426                 fsg->intr_in = ep;
3427         }
3428
3429         /* Fix up the descriptors */
3430         device_desc.idVendor = cpu_to_le16(mod_data.vendor);
3431         device_desc.idProduct = cpu_to_le16(mod_data.product);
3432         device_desc.bcdDevice = cpu_to_le16(mod_data.release);
3433
3434         i = (transport_is_cbi() ? 3 : 2);       // Number of endpoints
3435         fsg_intf_desc.bNumEndpoints = i;
3436         fsg_intf_desc.bInterfaceSubClass = mod_data.protocol_type;
3437         fsg_intf_desc.bInterfaceProtocol = mod_data.transport_type;
3438         fsg_fs_function[i + FSG_FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3439
3440         if (gadget_is_dualspeed(gadget)) {
3441                 fsg_hs_function[i + FSG_HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3442
3443                 /* Assume endpoint addresses are the same for both speeds */
3444                 fsg_hs_bulk_in_desc.bEndpointAddress =
3445                         fsg_fs_bulk_in_desc.bEndpointAddress;
3446                 fsg_hs_bulk_out_desc.bEndpointAddress =
3447                         fsg_fs_bulk_out_desc.bEndpointAddress;
3448                 fsg_hs_intr_in_desc.bEndpointAddress =
3449                         fsg_fs_intr_in_desc.bEndpointAddress;
3450         }
3451
3452         if (gadget_is_superspeed(gadget)) {
3453                 unsigned                max_burst;
3454
3455                 fsg_ss_function[i + FSG_SS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3456
3457                 /* Calculate bMaxBurst, we know packet size is 1024 */
3458                 max_burst = min_t(unsigned, mod_data.buflen / 1024, 15);
3459
3460                 /* Assume endpoint addresses are the same for both speeds */
3461                 fsg_ss_bulk_in_desc.bEndpointAddress =
3462                         fsg_fs_bulk_in_desc.bEndpointAddress;
3463                 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3464
3465                 fsg_ss_bulk_out_desc.bEndpointAddress =
3466                         fsg_fs_bulk_out_desc.bEndpointAddress;
3467                 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3468         }
3469
3470         if (gadget_is_otg(gadget))
3471                 fsg_otg_desc.bmAttributes |= USB_OTG_HNP;
3472
3473         rc = -ENOMEM;
3474
3475         /* Allocate the request and buffer for endpoint 0 */
3476         fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL);
3477         if (!req)
3478                 goto out;
3479         req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL);
3480         if (!req->buf)
3481                 goto out;
3482         req->complete = ep0_complete;
3483
3484         /* Allocate the data buffers */
3485         for (i = 0; i < fsg_num_buffers; ++i) {
3486                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
3487
3488                 /* Allocate for the bulk-in endpoint.  We assume that
3489                  * the buffer will also work with the bulk-out (and
3490                  * interrupt-in) endpoint. */
3491                 bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL);
3492                 if (!bh->buf)
3493                         goto out;
3494                 bh->next = bh + 1;
3495         }
3496         fsg->buffhds[fsg_num_buffers - 1].next = &fsg->buffhds[0];
3497
3498         /* This should reflect the actual gadget power source */
3499         usb_gadget_set_selfpowered(gadget);
3500
3501         snprintf(fsg_string_manufacturer, sizeof fsg_string_manufacturer,
3502                         "%s %s with %s",
3503                         init_utsname()->sysname, init_utsname()->release,
3504                         gadget->name);
3505
3506         fsg->thread_task = kthread_create(fsg_main_thread, fsg,
3507                         "file-storage-gadget");
3508         if (IS_ERR(fsg->thread_task)) {
3509                 rc = PTR_ERR(fsg->thread_task);
3510                 goto out;
3511         }
3512
3513         INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
3514         INFO(fsg, "NOTE: This driver is deprecated.  "
3515                         "Consider using g_mass_storage instead.\n");
3516         INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
3517
3518         pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
3519         for (i = 0; i < fsg->nluns; ++i) {
3520                 curlun = &fsg->luns[i];
3521                 if (fsg_lun_is_open(curlun)) {
3522                         p = NULL;
3523                         if (pathbuf) {
3524                                 p = d_path(&curlun->filp->f_path,
3525                                            pathbuf, PATH_MAX);
3526                                 if (IS_ERR(p))
3527                                         p = NULL;
3528                         }
3529                         LINFO(curlun, "ro=%d, nofua=%d, file: %s\n",
3530                               curlun->ro, curlun->nofua, (p ? p : "(error)"));
3531                 }
3532         }
3533         kfree(pathbuf);
3534
3535         DBG(fsg, "transport=%s (x%02x)\n",
3536                         mod_data.transport_name, mod_data.transport_type);
3537         DBG(fsg, "protocol=%s (x%02x)\n",
3538                         mod_data.protocol_name, mod_data.protocol_type);
3539         DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n",
3540                         mod_data.vendor, mod_data.product, mod_data.release);
3541         DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n",
3542                         mod_data.removable, mod_data.can_stall,
3543                         mod_data.cdrom, mod_data.buflen);
3544         DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
3545
3546         set_bit(REGISTERED, &fsg->atomic_bitflags);
3547
3548         /* Tell the thread to start working */
3549         wake_up_process(fsg->thread_task);
3550         return 0;
3551
3552 autoconf_fail:
3553         ERROR(fsg, "unable to autoconfigure all endpoints\n");
3554         rc = -ENOTSUPP;
3555
3556 out:
3557         fsg->state = FSG_STATE_TERMINATED;      // The thread is dead
3558         fsg_unbind(gadget);
3559         complete(&fsg->thread_notifier);
3560         return rc;
3561 }
3562
3563
3564 /*-------------------------------------------------------------------------*/
3565
3566 static void fsg_suspend(struct usb_gadget *gadget)
3567 {
3568         struct fsg_dev          *fsg = get_gadget_data(gadget);
3569
3570         DBG(fsg, "suspend\n");
3571         set_bit(SUSPENDED, &fsg->atomic_bitflags);
3572 }
3573
3574 static void fsg_resume(struct usb_gadget *gadget)
3575 {
3576         struct fsg_dev          *fsg = get_gadget_data(gadget);
3577
3578         DBG(fsg, "resume\n");
3579         clear_bit(SUSPENDED, &fsg->atomic_bitflags);
3580 }
3581
3582
3583 /*-------------------------------------------------------------------------*/
3584
3585 static struct usb_gadget_driver         fsg_driver = {
3586         .speed          = USB_SPEED_SUPER,
3587         .function       = (char *) fsg_string_product,
3588         .unbind         = fsg_unbind,
3589         .disconnect     = fsg_disconnect,
3590         .setup          = fsg_setup,
3591         .suspend        = fsg_suspend,
3592         .resume         = fsg_resume,
3593
3594         .driver         = {
3595                 .name           = DRIVER_NAME,
3596                 .owner          = THIS_MODULE,
3597                 // .release = ...
3598                 // .suspend = ...
3599                 // .resume = ...
3600         },
3601 };
3602
3603
3604 static int __init fsg_alloc(void)
3605 {
3606         struct fsg_dev          *fsg;
3607
3608         fsg = kzalloc(sizeof *fsg +
3609                       fsg_num_buffers * sizeof *(fsg->buffhds), GFP_KERNEL);
3610
3611         if (!fsg)
3612                 return -ENOMEM;
3613         spin_lock_init(&fsg->lock);
3614         init_rwsem(&fsg->filesem);
3615         kref_init(&fsg->ref);
3616         init_completion(&fsg->thread_notifier);
3617
3618         the_fsg = fsg;
3619         return 0;
3620 }
3621
3622
3623 static int __init fsg_init(void)
3624 {
3625         int             rc;
3626         struct fsg_dev  *fsg;
3627
3628         rc = fsg_num_buffers_validate();
3629         if (rc != 0)
3630                 return rc;
3631
3632         if ((rc = fsg_alloc()) != 0)
3633                 return rc;
3634         fsg = the_fsg;
3635         if ((rc = usb_gadget_probe_driver(&fsg_driver, fsg_bind)) != 0)
3636                 kref_put(&fsg->ref, fsg_release);
3637         return rc;
3638 }
3639 module_init(fsg_init);
3640
3641
3642 static void __exit fsg_cleanup(void)
3643 {
3644         struct fsg_dev  *fsg = the_fsg;
3645
3646         /* Unregister the driver iff the thread hasn't already done so */
3647         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
3648                 usb_gadget_unregister_driver(&fsg_driver);
3649
3650         /* Wait for the thread to finish up */
3651         wait_for_completion(&fsg->thread_notifier);
3652
3653         kref_put(&fsg->ref, fsg_release);
3654 }
3655 module_exit(fsg_cleanup);