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/module.h>
 247 #include <linux/rwsem.h>
 248 #include <linux/slab.h>
 249 #include <linux/spinlock.h>
 250 #include <linux/string.h>
 251 #include <linux/freezer.h>
 252 #include <linux/utsname.h>
 253
 254 #include <linux/usb/ch9.h>
 255 #include <linux/usb/gadget.h>
 256
 257 #include "gadget_chips.h"
 258
 259
 260
 261 /*
 262  * Kbuild is not very cooperative with respect to linking separately
 263  * compiled library objects into one module.  So for now we won't use
 264  * separate compilation ... ensuring init/exit sections work to shrink
 265  * the runtime footprint, and giving us at least some parts of what
 266  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
 267  */
 268 #include "usbstring.c"
 269 #include "config.c"
 270 #include "epautoconf.c"
 271
 272 /*-------------------------------------------------------------------------*/
 273
 274 #define DRIVER_DESC             "File-backed Storage Gadget"
 275 #define DRIVER_NAME             "g_file_storage"
 276 #define DRIVER_VERSION          "1 September 2010"
 277
 278 static       char fsg_string_manufacturer[64];
 279 static const char fsg_string_product[] = DRIVER_DESC;
 280 static const char fsg_string_config[] = "Self-powered";
 281 static const char fsg_string_interface[] = "Mass Storage";
 282
 283
 284 #include "storage_common.c"
 285
 286
 287 MODULE_DESCRIPTION(DRIVER_DESC);
 288 MODULE_AUTHOR("Alan Stern");
 289 MODULE_LICENSE("Dual BSD/GPL");
 290
 291 /*
 292  * This driver assumes self-powered hardware and has no way for users to
 293  * trigger remote wakeup.  It uses autoconfiguration to select endpoints
 294  * and endpoint addresses.
 295  */
 296
 297
 298 /*-------------------------------------------------------------------------*/
 299
 300
 301 /* Encapsulate the module parameter settings */
 302
 303 static struct {
 304         char            *file[FSG_MAX_LUNS];
 305         char            *serial;
 306         bool            ro[FSG_MAX_LUNS];
 307         bool            nofua[FSG_MAX_LUNS];
 308         unsigned int    num_filenames;
 309         unsigned int    num_ros;
 310         unsigned int    num_nofuas;
 311         unsigned int    nluns;
 312
 313         bool            removable;
 314         bool            can_stall;
 315         bool            cdrom;
 316
 317         char            *transport_parm;
 318         char            *protocol_parm;
 319         unsigned short  vendor;
 320         unsigned short  product;
 321         unsigned short  release;
 322         unsigned int    buflen;
 323
 324         int             transport_type;
 325         char            *transport_name;
 326         int             protocol_type;
 327         char            *protocol_name;
 328
 329 } mod_data = {                                  // Default values
 330         .transport_parm         = "BBB",
 331         .protocol_parm          = "SCSI",
 332         .removable              = 0,
 333         .can_stall              = 1,
 334         .cdrom                  = 0,
 335         .vendor                 = FSG_VENDOR_ID,
 336         .product                = FSG_PRODUCT_ID,
 337         .release                = 0xffff,       // Use controller chip type
 338         .buflen                 = 16384,
 339         };
 340
 341
 342 module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
 343                 S_IRUGO);
 344 MODULE_PARM_DESC(file, "names of backing files or devices");
 345
 346 module_param_named(serial, mod_data.serial, charp, S_IRUGO);
 347 MODULE_PARM_DESC(serial, "USB serial number");
 348
 349 module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
 350 MODULE_PARM_DESC(ro, "true to force read-only");
 351
 352 module_param_array_named(nofua, mod_data.nofua, bool, &mod_data.num_nofuas,
 353                 S_IRUGO);
 354 MODULE_PARM_DESC(nofua, "true to ignore SCSI WRITE(10,12) FUA bit");
 355
 356 module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
 357 MODULE_PARM_DESC(luns, "number of LUNs");
 358
 359 module_param_named(removable, mod_data.removable, bool, S_IRUGO);
 360 MODULE_PARM_DESC(removable, "true to simulate removable media");
 361
 362 module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
 363 MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
 364
 365 module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO);
 366 MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk");
 367
 368 /* In the non-TEST version, only the module parameters listed above
 369  * are available. */
 370 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 371
 372 module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
 373 MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
 374
 375 module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
 376 MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
 377                 "8070, or SCSI)");
 378
 379 module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
 380 MODULE_PARM_DESC(vendor, "USB Vendor ID");
 381
 382 module_param_named(product, mod_data.product, ushort, S_IRUGO);
 383 MODULE_PARM_DESC(product, "USB Product ID");
 384
 385 module_param_named(release, mod_data.release, ushort, S_IRUGO);
 386 MODULE_PARM_DESC(release, "USB release number");
 387
 388 module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
 389 MODULE_PARM_DESC(buflen, "I/O buffer size");
 390
 391 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 392
 393
 394 /*
 395  * These definitions will permit the compiler to avoid generating code for
 396  * parts of the driver that aren't used in the non-TEST version.  Even gcc
 397  * can recognize when a test of a constant expression yields a dead code
 398  * path.
 399  */
 400
 401 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 402
 403 #define transport_is_bbb()      (mod_data.transport_type == USB_PR_BULK)
 404 #define transport_is_cbi()      (mod_data.transport_type == USB_PR_CBI)
 405 #define protocol_is_scsi()      (mod_data.protocol_type == USB_SC_SCSI)
 406
 407 #else
 408
 409 #define transport_is_bbb()      1
 410 #define transport_is_cbi()      0
 411 #define protocol_is_scsi()      1
 412
 413 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 414
 415
 416 /*-------------------------------------------------------------------------*/
 417
 418
 419 struct fsg_dev {
 420         /* lock protects: state, all the req_busy's, and cbbuf_cmnd */
 421         spinlock_t              lock;
 422         struct usb_gadget       *gadget;
 423
 424         /* filesem protects: backing files in use */
 425         struct rw_semaphore     filesem;
 426
 427         /* reference counting: wait until all LUNs are released */
 428         struct kref             ref;
 429
 430         struct usb_ep           *ep0;           // Handy copy of gadget->ep0
 431         struct usb_request      *ep0req;        // For control responses
 432         unsigned int            ep0_req_tag;
 433         const char              *ep0req_name;
 434
 435         struct usb_request      *intreq;        // For interrupt responses
 436         int                     intreq_busy;
 437         struct fsg_buffhd       *intr_buffhd;
 438
 439         unsigned int            bulk_out_maxpacket;
 440         enum fsg_state          state;          // For exception handling
 441         unsigned int            exception_req_tag;
 442
 443         u8                      config, new_config;
 444
 445         unsigned int            running : 1;
 446         unsigned int            bulk_in_enabled : 1;
 447         unsigned int            bulk_out_enabled : 1;
 448         unsigned int            intr_in_enabled : 1;
 449         unsigned int            phase_error : 1;
 450         unsigned int            short_packet_received : 1;
 451         unsigned int            bad_lun_okay : 1;
 452
 453         unsigned long           atomic_bitflags;
 454 #define REGISTERED              0
 455 #define IGNORE_BULK_OUT         1
 456 #define SUSPENDED               2
 457
 458         struct usb_ep           *bulk_in;
 459         struct usb_ep           *bulk_out;
 460         struct usb_ep           *intr_in;
 461
 462         struct fsg_buffhd       *next_buffhd_to_fill;
 463         struct fsg_buffhd       *next_buffhd_to_drain;
 464
 465         int                     thread_wakeup_needed;
 466         struct completion       thread_notifier;
 467         struct task_struct      *thread_task;
 468
 469         int                     cmnd_size;
 470         u8                      cmnd[MAX_COMMAND_SIZE];
 471         enum data_direction     data_dir;
 472         u32                     data_size;
 473         u32                     data_size_from_cmnd;
 474         u32                     tag;
 475         unsigned int            lun;
 476         u32                     residue;
 477         u32                     usb_amount_left;
 478
 479         /* The CB protocol offers no way for a host to know when a command
 480          * has completed.  As a result the next command may arrive early,
 481          * and we will still have to handle it.  For that reason we need
 482          * a buffer to store new commands when using CB (or CBI, which
 483          * does not oblige a host to wait for command completion either). */
 484         int                     cbbuf_cmnd_size;
 485         u8                      cbbuf_cmnd[MAX_COMMAND_SIZE];
 486
 487         unsigned int            nluns;
 488         struct fsg_lun          *luns;
 489         struct fsg_lun          *curlun;
 490         /* Must be the last entry */
 491         struct fsg_buffhd       buffhds[];
 492 };
 493
 494 typedef void (*fsg_routine_t)(struct fsg_dev *);
 495
 496 static int exception_in_progress(struct fsg_dev *fsg)
 497 {
 498         return (fsg->state > FSG_STATE_IDLE);
 499 }
 500
 501 /* Make bulk-out requests be divisible by the maxpacket size */
 502 static void set_bulk_out_req_length(struct fsg_dev *fsg,
 503                 struct fsg_buffhd *bh, unsigned int length)
 504 {
 505         unsigned int    rem;
 506
 507         bh->bulk_out_intended_length = length;
 508         rem = length % fsg->bulk_out_maxpacket;
 509         if (rem > 0)
 510                 length += fsg->bulk_out_maxpacket - rem;
 511         bh->outreq->length = length;
 512 }
 513
 514 static struct fsg_dev                   *the_fsg;
 515 static struct usb_gadget_driver         fsg_driver;
 516
 517
 518 /*-------------------------------------------------------------------------*/
 519
 520 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
 521 {
 522         const char      *name;
 523
 524         if (ep == fsg->bulk_in)
 525                 name = "bulk-in";
 526         else if (ep == fsg->bulk_out)
 527                 name = "bulk-out";
 528         else
 529                 name = ep->name;
 530         DBG(fsg, "%s set halt\n", name);
 531         return usb_ep_set_halt(ep);
 532 }
 533
 534
 535 /*-------------------------------------------------------------------------*/
 536
 537 /*
 538  * DESCRIPTORS ... most are static, but strings and (full) configuration
 539  * descriptors are built on demand.  Also the (static) config and interface
 540  * descriptors are adjusted during fsg_bind().
 541  */
 542
 543 /* There is only one configuration. */
 544 #define CONFIG_VALUE            1
 545
 546 static struct usb_device_descriptor
 547 device_desc = {
 548         .bLength =              sizeof device_desc,
 549         .bDescriptorType =      USB_DT_DEVICE,
 550
 551         .bcdUSB =               cpu_to_le16(0x0200),
 552         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 553
 554         /* The next three values can be overridden by module parameters */
 555         .idVendor =             cpu_to_le16(FSG_VENDOR_ID),
 556         .idProduct =            cpu_to_le16(FSG_PRODUCT_ID),
 557         .bcdDevice =            cpu_to_le16(0xffff),
 558
 559         .iManufacturer =        FSG_STRING_MANUFACTURER,
 560         .iProduct =             FSG_STRING_PRODUCT,
 561         .iSerialNumber =        FSG_STRING_SERIAL,
 562         .bNumConfigurations =   1,
 563 };
 564
 565 static struct usb_config_descriptor
 566 config_desc = {
 567         .bLength =              sizeof config_desc,
 568         .bDescriptorType =      USB_DT_CONFIG,
 569
 570         /* wTotalLength computed by usb_gadget_config_buf() */
 571         .bNumInterfaces =       1,
 572         .bConfigurationValue =  CONFIG_VALUE,
 573         .iConfiguration =       FSG_STRING_CONFIG,
 574         .bmAttributes =         USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
 575         .bMaxPower =            CONFIG_USB_GADGET_VBUS_DRAW / 2,
 576 };
 577
 578
 579 static struct usb_qualifier_descriptor
 580 dev_qualifier = {
 581         .bLength =              sizeof dev_qualifier,
 582         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 583
 584         .bcdUSB =               cpu_to_le16(0x0200),
 585         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 586
 587         .bNumConfigurations =   1,
 588 };
 589
 590 static int populate_bos(struct fsg_dev *fsg, u8 *buf)
 591 {
 592         memcpy(buf, &fsg_bos_desc, USB_DT_BOS_SIZE);
 593         buf += USB_DT_BOS_SIZE;
 594
 595         memcpy(buf, &fsg_ext_cap_desc, USB_DT_USB_EXT_CAP_SIZE);
 596         buf += USB_DT_USB_EXT_CAP_SIZE;
 597
 598         memcpy(buf, &fsg_ss_cap_desc, USB_DT_USB_SS_CAP_SIZE);
 599
 600         return USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE
 601                 + USB_DT_USB_EXT_CAP_SIZE;
 602 }
 603
 604 /*
 605  * Config descriptors must agree with the code that sets configurations
 606  * and with code managing interfaces and their altsettings.  They must
 607  * also handle different speeds and other-speed requests.
 608  */
 609 static int populate_config_buf(struct usb_gadget *gadget,
 610                 u8 *buf, u8 type, unsigned index)
 611 {
 612         enum usb_device_speed                   speed = gadget->speed;
 613         int                                     len;
 614         const struct usb_descriptor_header      **function;
 615
 616         if (index > 0)
 617                 return -EINVAL;
 618
 619         if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
 620                 speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
 621         function = gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH
 622                 ? (const struct usb_descriptor_header **)fsg_hs_function
 623                 : (const struct usb_descriptor_header **)fsg_fs_function;
 624
 625         /* for now, don't advertise srp-only devices */
 626         if (!gadget_is_otg(gadget))
 627                 function++;
 628
 629         len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
 630         ((struct usb_config_descriptor *) buf)->bDescriptorType = type;
 631         return len;
 632 }
 633
 634
 635 /*-------------------------------------------------------------------------*/
 636
 637 /* These routines may be called in process context or in_irq */
 638
 639 /* Caller must hold fsg->lock */
 640 static void wakeup_thread(struct fsg_dev *fsg)
 641 {
 642         /* Tell the main thread that something has happened */
 643         fsg->thread_wakeup_needed = 1;
 644         if (fsg->thread_task)
 645                 wake_up_process(fsg->thread_task);
 646 }
 647
 648
 649 static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
 650 {
 651         unsigned long           flags;
 652
 653         /* Do nothing if a higher-priority exception is already in progress.
 654          * If a lower-or-equal priority exception is in progress, preempt it
 655          * and notify the main thread by sending it a signal. */
 656         spin_lock_irqsave(&fsg->lock, flags);
 657         if (fsg->state <= new_state) {
 658                 fsg->exception_req_tag = fsg->ep0_req_tag;
 659                 fsg->state = new_state;
 660                 if (fsg->thread_task)
 661                         send_sig_info(SIGUSR1, SEND_SIG_FORCED,
 662                                         fsg->thread_task);
 663         }
 664         spin_unlock_irqrestore(&fsg->lock, flags);
 665 }
 666
 667
 668 /*-------------------------------------------------------------------------*/
 669
 670 /* The disconnect callback and ep0 routines.  These always run in_irq,
 671  * except that ep0_queue() is called in the main thread to acknowledge
 672  * completion of various requests: set config, set interface, and
 673  * Bulk-only device reset. */
 674
 675 static void fsg_disconnect(struct usb_gadget *gadget)
 676 {
 677         struct fsg_dev          *fsg = get_gadget_data(gadget);
 678
 679         DBG(fsg, "disconnect or port reset\n");
 680         raise_exception(fsg, FSG_STATE_DISCONNECT);
 681 }
 682
 683
 684 static int ep0_queue(struct fsg_dev *fsg)
 685 {
 686         int     rc;
 687
 688         rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
 689         if (rc != 0 && rc != -ESHUTDOWN) {
 690
 691                 /* We can't do much more than wait for a reset */
 692                 WARNING(fsg, "error in submission: %s --> %d\n",
 693                                 fsg->ep0->name, rc);
 694         }
 695         return rc;
 696 }
 697
 698 static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
 699 {
 700         struct fsg_dev          *fsg = ep->driver_data;
 701
 702         if (req->actual > 0)
 703                 dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
 704         if (req->status || req->actual != req->length)
 705                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 706                                 req->status, req->actual, req->length);
 707         if (req->status == -ECONNRESET)         // Request was cancelled
 708                 usb_ep_fifo_flush(ep);
 709
 710         if (req->status == 0 && req->context)
 711                 ((fsg_routine_t) (req->context))(fsg);
 712 }
 713
 714
 715 /*-------------------------------------------------------------------------*/
 716
 717 /* Bulk and interrupt endpoint completion handlers.
 718  * These always run in_irq. */
 719
 720 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
 721 {
 722         struct fsg_dev          *fsg = ep->driver_data;
 723         struct fsg_buffhd       *bh = req->context;
 724
 725         if (req->status || req->actual != req->length)
 726                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 727                                 req->status, req->actual, req->length);
 728         if (req->status == -ECONNRESET)         // Request was cancelled
 729                 usb_ep_fifo_flush(ep);
 730
 731         /* Hold the lock while we update the request and buffer states */
 732         smp_wmb();
 733         spin_lock(&fsg->lock);
 734         bh->inreq_busy = 0;
 735         bh->state = BUF_STATE_EMPTY;
 736         wakeup_thread(fsg);
 737         spin_unlock(&fsg->lock);
 738 }
 739
 740 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
 741 {
 742         struct fsg_dev          *fsg = ep->driver_data;
 743         struct fsg_buffhd       *bh = req->context;
 744
 745         dump_msg(fsg, "bulk-out", req->buf, req->actual);
 746         if (req->status || req->actual != bh->bulk_out_intended_length)
 747                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 748                                 req->status, req->actual,
 749                                 bh->bulk_out_intended_length);
 750         if (req->status == -ECONNRESET)         // Request was cancelled
 751                 usb_ep_fifo_flush(ep);
 752
 753         /* Hold the lock while we update the request and buffer states */
 754         smp_wmb();
 755         spin_lock(&fsg->lock);
 756         bh->outreq_busy = 0;
 757         bh->state = BUF_STATE_FULL;
 758         wakeup_thread(fsg);
 759         spin_unlock(&fsg->lock);
 760 }
 761
 762
 763 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 764 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
 765 {
 766         struct fsg_dev          *fsg = ep->driver_data;
 767         struct fsg_buffhd       *bh = req->context;
 768
 769         if (req->status || req->actual != req->length)
 770                 DBG(fsg, "%s --> %d, %u/%u\n", __func__,
 771                                 req->status, req->actual, req->length);
 772         if (req->status == -ECONNRESET)         // Request was cancelled
 773                 usb_ep_fifo_flush(ep);
 774
 775         /* Hold the lock while we update the request and buffer states */
 776         smp_wmb();
 777         spin_lock(&fsg->lock);
 778         fsg->intreq_busy = 0;
 779         bh->state = BUF_STATE_EMPTY;
 780         wakeup_thread(fsg);
 781         spin_unlock(&fsg->lock);
 782 }
 783
 784 #else
 785 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
 786 {}
 787 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 788
 789
 790 /*-------------------------------------------------------------------------*/
 791
 792 /* Ep0 class-specific handlers.  These always run in_irq. */
 793
 794 #ifdef CONFIG_USB_FILE_STORAGE_TEST
 795 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 796 {
 797         struct usb_request      *req = fsg->ep0req;
 798         static u8               cbi_reset_cmnd[6] = {
 799                         SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
 800
 801         /* Error in command transfer? */
 802         if (req->status || req->length != req->actual ||
 803                         req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
 804
 805                 /* Not all controllers allow a protocol stall after
 806                  * receiving control-out data, but we'll try anyway. */
 807                 fsg_set_halt(fsg, fsg->ep0);
 808                 return;                 // Wait for reset
 809         }
 810
 811         /* Is it the special reset command? */
 812         if (req->actual >= sizeof cbi_reset_cmnd &&
 813                         memcmp(req->buf, cbi_reset_cmnd,
 814                                 sizeof cbi_reset_cmnd) == 0) {
 815
 816                 /* Raise an exception to stop the current operation
 817                  * and reinitialize our state. */
 818                 DBG(fsg, "cbi reset request\n");
 819                 raise_exception(fsg, FSG_STATE_RESET);
 820                 return;
 821         }
 822
 823         VDBG(fsg, "CB[I] accept device-specific command\n");
 824         spin_lock(&fsg->lock);
 825
 826         /* Save the command for later */
 827         if (fsg->cbbuf_cmnd_size)
 828                 WARNING(fsg, "CB[I] overwriting previous command\n");
 829         fsg->cbbuf_cmnd_size = req->actual;
 830         memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
 831
 832         wakeup_thread(fsg);
 833         spin_unlock(&fsg->lock);
 834 }
 835
 836 #else
 837 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
 838 {}
 839 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
 840
 841
 842 static int class_setup_req(struct fsg_dev *fsg,
 843                 const struct usb_ctrlrequest *ctrl)
 844 {
 845         struct usb_request      *req = fsg->ep0req;
 846         int                     value = -EOPNOTSUPP;
 847         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 848         u16                     w_value = le16_to_cpu(ctrl->wValue);
 849         u16                     w_length = le16_to_cpu(ctrl->wLength);
 850
 851         if (!fsg->config)
 852                 return value;
 853
 854         /* Handle Bulk-only class-specific requests */
 855         if (transport_is_bbb()) {
 856                 switch (ctrl->bRequest) {
 857
 858                 case US_BULK_RESET_REQUEST:
 859                         if (ctrl->bRequestType != (USB_DIR_OUT |
 860                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 861                                 break;
 862                         if (w_index != 0 || w_value != 0 || w_length != 0) {
 863                                 value = -EDOM;
 864                                 break;
 865                         }
 866
 867                         /* Raise an exception to stop the current operation
 868                          * and reinitialize our state. */
 869                         DBG(fsg, "bulk reset request\n");
 870                         raise_exception(fsg, FSG_STATE_RESET);
 871                         value = DELAYED_STATUS;
 872                         break;
 873
 874                 case US_BULK_GET_MAX_LUN:
 875                         if (ctrl->bRequestType != (USB_DIR_IN |
 876                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 877                                 break;
 878                         if (w_index != 0 || w_value != 0 || w_length != 1) {
 879                                 value = -EDOM;
 880                                 break;
 881                         }
 882                         VDBG(fsg, "get max LUN\n");
 883                         *(u8 *) req->buf = fsg->nluns - 1;
 884                         value = 1;
 885                         break;
 886                 }
 887         }
 888
 889         /* Handle CBI class-specific requests */
 890         else {
 891                 switch (ctrl->bRequest) {
 892
 893                 case USB_CBI_ADSC_REQUEST:
 894                         if (ctrl->bRequestType != (USB_DIR_OUT |
 895                                         USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 896                                 break;
 897                         if (w_index != 0 || w_value != 0) {
 898                                 value = -EDOM;
 899                                 break;
 900                         }
 901                         if (w_length > MAX_COMMAND_SIZE) {
 902                                 value = -EOVERFLOW;
 903                                 break;
 904                         }
 905                         value = w_length;
 906                         fsg->ep0req->context = received_cbi_adsc;
 907                         break;
 908                 }
 909         }
 910
 911         if (value == -EOPNOTSUPP)
 912                 VDBG(fsg,
 913                         "unknown class-specific control req "
 914                         "%02x.%02x v%04x i%04x l%u\n",
 915                         ctrl->bRequestType, ctrl->bRequest,
 916                         le16_to_cpu(ctrl->wValue), w_index, w_length);
 917         return value;
 918 }
 919
 920
 921 /*-------------------------------------------------------------------------*/
 922
 923 /* Ep0 standard request handlers.  These always run in_irq. */
 924
 925 static int standard_setup_req(struct fsg_dev *fsg,
 926                 const struct usb_ctrlrequest *ctrl)
 927 {
 928         struct usb_request      *req = fsg->ep0req;
 929         int                     value = -EOPNOTSUPP;
 930         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 931         u16                     w_value = le16_to_cpu(ctrl->wValue);
 932
 933         /* Usually this just stores reply data in the pre-allocated ep0 buffer,
 934          * but config change events will also reconfigure hardware. */
 935         switch (ctrl->bRequest) {
 936
 937         case USB_REQ_GET_DESCRIPTOR:
 938                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
 939                                 USB_RECIP_DEVICE))
 940                         break;
 941                 switch (w_value >> 8) {
 942
 943                 case USB_DT_DEVICE:
 944                         VDBG(fsg, "get device descriptor\n");
 945                         device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
 946                         value = sizeof device_desc;
 947                         memcpy(req->buf, &device_desc, value);
 948                         break;
 949                 case USB_DT_DEVICE_QUALIFIER:
 950                         VDBG(fsg, "get device qualifier\n");
 951                         if (!gadget_is_dualspeed(fsg->gadget) ||
 952                                         fsg->gadget->speed == USB_SPEED_SUPER)
 953                                 break;
 954                         /*
 955                          * Assume ep0 uses the same maxpacket value for both
 956                          * speeds
 957                          */
 958                         dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
 959                         value = sizeof dev_qualifier;
 960                         memcpy(req->buf, &dev_qualifier, value);
 961                         break;
 962
 963                 case USB_DT_OTHER_SPEED_CONFIG:
 964                         VDBG(fsg, "get other-speed config descriptor\n");
 965                         if (!gadget_is_dualspeed(fsg->gadget) ||
 966                                         fsg->gadget->speed == USB_SPEED_SUPER)
 967                                 break;
 968                         goto get_config;
 969                 case USB_DT_CONFIG:
 970                         VDBG(fsg, "get configuration descriptor\n");
 971 get_config:
 972                         value = populate_config_buf(fsg->gadget,
 973                                         req->buf,
 974                                         w_value >> 8,
 975                                         w_value & 0xff);
 976                         break;
 977
 978                 case USB_DT_STRING:
 979                         VDBG(fsg, "get string descriptor\n");
 980
 981                         /* wIndex == language code */
 982                         value = usb_gadget_get_string(&fsg_stringtab,
 983                                         w_value & 0xff, req->buf);
 984                         break;
 985
 986                 case USB_DT_BOS:
 987                         VDBG(fsg, "get bos descriptor\n");
 988
 989                         if (gadget_is_superspeed(fsg->gadget))
 990                                 value = populate_bos(fsg, req->buf);
 991                         break;
 992                 }
 993
 994                 break;
 995
 996         /* One config, two speeds */
 997         case USB_REQ_SET_CONFIGURATION:
 998                 if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
 999                                 USB_RECIP_DEVICE))
1000                         break;
1001                 VDBG(fsg, "set configuration\n");
1002                 if (w_value == CONFIG_VALUE || w_value == 0) {
1003                         fsg->new_config = w_value;
1004
1005                         /* Raise an exception to wipe out previous transaction
1006                          * state (queued bufs, etc) and set the new config. */
1007                         raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
1008                         value = DELAYED_STATUS;
1009                 }
1010                 break;
1011         case USB_REQ_GET_CONFIGURATION:
1012                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1013                                 USB_RECIP_DEVICE))
1014                         break;
1015                 VDBG(fsg, "get configuration\n");
1016                 *(u8 *) req->buf = fsg->config;
1017                 value = 1;
1018                 break;
1019
1020         case USB_REQ_SET_INTERFACE:
1021                 if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD |
1022                                 USB_RECIP_INTERFACE))
1023                         break;
1024                 if (fsg->config && w_index == 0) {
1025
1026                         /* Raise an exception to wipe out previous transaction
1027                          * state (queued bufs, etc) and install the new
1028                          * interface altsetting. */
1029                         raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE);
1030                         value = DELAYED_STATUS;
1031                 }
1032                 break;
1033         case USB_REQ_GET_INTERFACE:
1034                 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1035                                 USB_RECIP_INTERFACE))
1036                         break;
1037                 if (!fsg->config)
1038                         break;
1039                 if (w_index != 0) {
1040                         value = -EDOM;
1041                         break;
1042                 }
1043                 VDBG(fsg, "get interface\n");
1044                 *(u8 *) req->buf = 0;
1045                 value = 1;
1046                 break;
1047
1048         default:
1049                 VDBG(fsg,
1050                         "unknown control req %02x.%02x v%04x i%04x l%u\n",
1051                         ctrl->bRequestType, ctrl->bRequest,
1052                         w_value, w_index, le16_to_cpu(ctrl->wLength));
1053         }
1054
1055         return value;
1056 }
1057
1058
1059 static int fsg_setup(struct usb_gadget *gadget,
1060                 const struct usb_ctrlrequest *ctrl)
1061 {
1062         struct fsg_dev          *fsg = get_gadget_data(gadget);
1063         int                     rc;
1064         int                     w_length = le16_to_cpu(ctrl->wLength);
1065
1066         ++fsg->ep0_req_tag;             // Record arrival of a new request
1067         fsg->ep0req->context = NULL;
1068         fsg->ep0req->length = 0;
1069         dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
1070
1071         if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS)
1072                 rc = class_setup_req(fsg, ctrl);
1073         else
1074                 rc = standard_setup_req(fsg, ctrl);
1075
1076         /* Respond with data/status or defer until later? */
1077         if (rc >= 0 && rc != DELAYED_STATUS) {
1078                 rc = min(rc, w_length);
1079                 fsg->ep0req->length = rc;
1080                 fsg->ep0req->zero = rc < w_length;
1081                 fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
1082                                 "ep0-in" : "ep0-out");
1083                 rc = ep0_queue(fsg);
1084         }
1085
1086         /* Device either stalls (rc < 0) or reports success */
1087         return rc;
1088 }
1089
1090
1091 /*-------------------------------------------------------------------------*/
1092
1093 /* All the following routines run in process context */
1094
1095
1096 /* Use this for bulk or interrupt transfers, not ep0 */
1097 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
1098                 struct usb_request *req, int *pbusy,
1099                 enum fsg_buffer_state *state)
1100 {
1101         int     rc;
1102
1103         if (ep == fsg->bulk_in)
1104                 dump_msg(fsg, "bulk-in", req->buf, req->length);
1105         else if (ep == fsg->intr_in)
1106                 dump_msg(fsg, "intr-in", req->buf, req->length);
1107
1108         spin_lock_irq(&fsg->lock);
1109         *pbusy = 1;
1110         *state = BUF_STATE_BUSY;
1111         spin_unlock_irq(&fsg->lock);
1112         rc = usb_ep_queue(ep, req, GFP_KERNEL);
1113         if (rc != 0) {
1114                 *pbusy = 0;
1115                 *state = BUF_STATE_EMPTY;
1116
1117                 /* We can't do much more than wait for a reset */
1118
1119                 /* Note: currently the net2280 driver fails zero-length
1120                  * submissions if DMA is enabled. */
1121                 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
1122                                                 req->length == 0))
1123                         WARNING(fsg, "error in submission: %s --> %d\n",
1124                                         ep->name, rc);
1125         }
1126 }
1127
1128
1129 static int sleep_thread(struct fsg_dev *fsg)
1130 {
1131         int     rc = 0;
1132
1133         /* Wait until a signal arrives or we are woken up */
1134         for (;;) {
1135                 try_to_freeze();
1136                 set_current_state(TASK_INTERRUPTIBLE);
1137                 if (signal_pending(current)) {
1138                         rc = -EINTR;
1139                         break;
1140                 }
1141                 if (fsg->thread_wakeup_needed)
1142                         break;
1143                 schedule();
1144         }
1145         __set_current_state(TASK_RUNNING);
1146         fsg->thread_wakeup_needed = 0;
1147         return rc;
1148 }
1149
1150
1151 /*-------------------------------------------------------------------------*/
1152
1153 static int do_read(struct fsg_dev *fsg)
1154 {
1155         struct fsg_lun          *curlun = fsg->curlun;
1156         u32                     lba;
1157         struct fsg_buffhd       *bh;
1158         int                     rc;
1159         u32                     amount_left;
1160         loff_t                  file_offset, file_offset_tmp;
1161         unsigned int            amount;
1162         ssize_t                 nread;
1163
1164         /* Get the starting Logical Block Address and check that it's
1165          * not too big */
1166         if (fsg->cmnd[0] == READ_6)
1167                 lba = get_unaligned_be24(&fsg->cmnd[1]);
1168         else {
1169                 lba = get_unaligned_be32(&fsg->cmnd[2]);
1170
1171                 /* We allow DPO (Disable Page Out = don't save data in the
1172                  * cache) and FUA (Force Unit Access = don't read from the
1173                  * cache), but we don't implement them. */
1174                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1175                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1176                         return -EINVAL;
1177                 }
1178         }
1179         if (lba >= curlun->num_sectors) {
1180                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1181                 return -EINVAL;
1182         }
1183         file_offset = ((loff_t) lba) << curlun->blkbits;
1184
1185         /* Carry out the file reads */
1186         amount_left = fsg->data_size_from_cmnd;
1187         if (unlikely(amount_left == 0))
1188                 return -EIO;            // No default reply
1189
1190         for (;;) {
1191
1192                 /* Figure out how much we need to read:
1193                  * Try to read the remaining amount.
1194                  * But don't read more than the buffer size.
1195                  * And don't try to read past the end of the file.
1196                  */
1197                 amount = min((unsigned int) amount_left, mod_data.buflen);
1198                 amount = min((loff_t) amount,
1199                                 curlun->file_length - file_offset);
1200
1201                 /* Wait for the next buffer to become available */
1202                 bh = fsg->next_buffhd_to_fill;
1203                 while (bh->state != BUF_STATE_EMPTY) {
1204                         rc = sleep_thread(fsg);
1205                         if (rc)
1206                                 return rc;
1207                 }
1208
1209                 /* If we were asked to read past the end of file,
1210                  * end with an empty buffer. */
1211                 if (amount == 0) {
1212                         curlun->sense_data =
1213                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1214                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1215                         curlun->info_valid = 1;
1216                         bh->inreq->length = 0;
1217                         bh->state = BUF_STATE_FULL;
1218                         break;
1219                 }
1220
1221                 /* Perform the read */
1222                 file_offset_tmp = file_offset;
1223                 nread = vfs_read(curlun->filp,
1224                                 (char __user *) bh->buf,
1225                                 amount, &file_offset_tmp);
1226                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1227                                 (unsigned long long) file_offset,
1228                                 (int) nread);
1229                 if (signal_pending(current))
1230                         return -EINTR;
1231
1232                 if (nread < 0) {
1233                         LDBG(curlun, "error in file read: %d\n",
1234                                         (int) nread);
1235                         nread = 0;
1236                 } else if (nread < amount) {
1237                         LDBG(curlun, "partial file read: %d/%u\n",
1238                                         (int) nread, amount);
1239                         nread = round_down(nread, curlun->blksize);
1240                 }
1241                 file_offset  += nread;
1242                 amount_left  -= nread;
1243                 fsg->residue -= nread;
1244
1245                 /* Except at the end of the transfer, nread will be
1246                  * equal to the buffer size, which is divisible by the
1247                  * bulk-in maxpacket size.
1248                  */
1249                 bh->inreq->length = nread;
1250                 bh->state = BUF_STATE_FULL;
1251
1252                 /* If an error occurred, report it and its position */
1253                 if (nread < amount) {
1254                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1255                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1256                         curlun->info_valid = 1;
1257                         break;
1258                 }
1259
1260                 if (amount_left == 0)
1261                         break;          // No more left to read
1262
1263                 /* Send this buffer and go read some more */
1264                 bh->inreq->zero = 0;
1265                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1266                                 &bh->inreq_busy, &bh->state);
1267                 fsg->next_buffhd_to_fill = bh->next;
1268         }
1269
1270         return -EIO;            // No default reply
1271 }
1272
1273
1274 /*-------------------------------------------------------------------------*/
1275
1276 static int do_write(struct fsg_dev *fsg)
1277 {
1278         struct fsg_lun          *curlun = fsg->curlun;
1279         u32                     lba;
1280         struct fsg_buffhd       *bh;
1281         int                     get_some_more;
1282         u32                     amount_left_to_req, amount_left_to_write;
1283         loff_t                  usb_offset, file_offset, file_offset_tmp;
1284         unsigned int            amount;
1285         ssize_t                 nwritten;
1286         int                     rc;
1287
1288         if (curlun->ro) {
1289                 curlun->sense_data = SS_WRITE_PROTECTED;
1290                 return -EINVAL;
1291         }
1292         spin_lock(&curlun->filp->f_lock);
1293         curlun->filp->f_flags &= ~O_SYNC;       // Default is not to wait
1294         spin_unlock(&curlun->filp->f_lock);
1295
1296         /* Get the starting Logical Block Address and check that it's
1297          * not too big */
1298         if (fsg->cmnd[0] == WRITE_6)
1299                 lba = get_unaligned_be24(&fsg->cmnd[1]);
1300         else {
1301                 lba = get_unaligned_be32(&fsg->cmnd[2]);
1302
1303                 /* We allow DPO (Disable Page Out = don't save data in the
1304                  * cache) and FUA (Force Unit Access = write directly to the
1305                  * medium).  We don't implement DPO; we implement FUA by
1306                  * performing synchronous output. */
1307                 if ((fsg->cmnd[1] & ~0x18) != 0) {
1308                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1309                         return -EINVAL;
1310                 }
1311                 /* FUA */
1312                 if (!curlun->nofua && (fsg->cmnd[1] & 0x08)) {
1313                         spin_lock(&curlun->filp->f_lock);
1314                         curlun->filp->f_flags |= O_DSYNC;
1315                         spin_unlock(&curlun->filp->f_lock);
1316                 }
1317         }
1318         if (lba >= curlun->num_sectors) {
1319                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1320                 return -EINVAL;
1321         }
1322
1323         /* Carry out the file writes */
1324         get_some_more = 1;
1325         file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
1326         amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd;
1327
1328         while (amount_left_to_write > 0) {
1329
1330                 /* Queue a request for more data from the host */
1331                 bh = fsg->next_buffhd_to_fill;
1332                 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
1333
1334                         /* Figure out how much we want to get:
1335                          * Try to get the remaining amount,
1336                          * but not more than the buffer size.
1337                          */
1338                         amount = min(amount_left_to_req, mod_data.buflen);
1339
1340                         /* Beyond the end of the backing file? */
1341                         if (usb_offset >= curlun->file_length) {
1342                                 get_some_more = 0;
1343                                 curlun->sense_data =
1344                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1345                                 curlun->sense_data_info = usb_offset >> curlun->blkbits;
1346                                 curlun->info_valid = 1;
1347                                 continue;
1348                         }
1349
1350                         /* Get the next buffer */
1351                         usb_offset += amount;
1352                         fsg->usb_amount_left -= amount;
1353                         amount_left_to_req -= amount;
1354                         if (amount_left_to_req == 0)
1355                                 get_some_more = 0;
1356
1357                         /* Except at the end of the transfer, amount will be
1358                          * equal to the buffer size, which is divisible by
1359                          * the bulk-out maxpacket size.
1360                          */
1361                         set_bulk_out_req_length(fsg, bh, amount);
1362                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
1363                                         &bh->outreq_busy, &bh->state);
1364                         fsg->next_buffhd_to_fill = bh->next;
1365                         continue;
1366                 }
1367
1368                 /* Write the received data to the backing file */
1369                 bh = fsg->next_buffhd_to_drain;
1370                 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
1371                         break;                  // We stopped early
1372                 if (bh->state == BUF_STATE_FULL) {
1373                         smp_rmb();
1374                         fsg->next_buffhd_to_drain = bh->next;
1375                         bh->state = BUF_STATE_EMPTY;
1376
1377                         /* Did something go wrong with the transfer? */
1378                         if (bh->outreq->status != 0) {
1379                                 curlun->sense_data = SS_COMMUNICATION_FAILURE;
1380                                 curlun->sense_data_info = file_offset >> curlun->blkbits;
1381                                 curlun->info_valid = 1;
1382                                 break;
1383                         }
1384
1385                         amount = bh->outreq->actual;
1386                         if (curlun->file_length - file_offset < amount) {
1387                                 LERROR(curlun,
1388         "write %u @ %llu beyond end %llu\n",
1389         amount, (unsigned long long) file_offset,
1390         (unsigned long long) curlun->file_length);
1391                                 amount = curlun->file_length - file_offset;
1392                         }
1393
1394                         /* Don't accept excess data.  The spec doesn't say
1395                          * what to do in this case.  We'll ignore the error.
1396                          */
1397                         amount = min(amount, bh->bulk_out_intended_length);
1398
1399                         /* Don't write a partial block */
1400                         amount = round_down(amount, curlun->blksize);
1401                         if (amount == 0)
1402                                 goto empty_write;
1403
1404                         /* Perform the write */
1405                         file_offset_tmp = file_offset;
1406                         nwritten = vfs_write(curlun->filp,
1407                                         (char __user *) bh->buf,
1408                                         amount, &file_offset_tmp);
1409                         VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1410                                         (unsigned long long) file_offset,
1411                                         (int) nwritten);
1412                         if (signal_pending(current))
1413                                 return -EINTR;          // Interrupted!
1414
1415                         if (nwritten < 0) {
1416                                 LDBG(curlun, "error in file write: %d\n",
1417                                                 (int) nwritten);
1418                                 nwritten = 0;
1419                         } else if (nwritten < amount) {
1420                                 LDBG(curlun, "partial file write: %d/%u\n",
1421                                                 (int) nwritten, amount);
1422                                 nwritten = round_down(nwritten, curlun->blksize);
1423                         }
1424                         file_offset += nwritten;
1425                         amount_left_to_write -= nwritten;
1426                         fsg->residue -= nwritten;
1427
1428                         /* If an error occurred, report it and its position */
1429                         if (nwritten < amount) {
1430                                 curlun->sense_data = SS_WRITE_ERROR;
1431                                 curlun->sense_data_info = file_offset >> curlun->blkbits;
1432                                 curlun->info_valid = 1;
1433                                 break;
1434                         }
1435
1436  empty_write:
1437                         /* Did the host decide to stop early? */
1438                         if (bh->outreq->actual < bh->bulk_out_intended_length) {
1439                                 fsg->short_packet_received = 1;
1440                                 break;
1441                         }
1442                         continue;
1443                 }
1444
1445                 /* Wait for something to happen */
1446                 rc = sleep_thread(fsg);
1447                 if (rc)
1448                         return rc;
1449         }
1450
1451         return -EIO;            // No default reply
1452 }
1453
1454
1455 /*-------------------------------------------------------------------------*/
1456
1457 static int do_synchronize_cache(struct fsg_dev *fsg)
1458 {
1459         struct fsg_lun  *curlun = fsg->curlun;
1460         int             rc;
1461
1462         /* We ignore the requested LBA and write out all file's
1463          * dirty data buffers. */
1464         rc = fsg_lun_fsync_sub(curlun);
1465         if (rc)
1466                 curlun->sense_data = SS_WRITE_ERROR;
1467         return 0;
1468 }
1469
1470
1471 /*-------------------------------------------------------------------------*/
1472
1473 static void invalidate_sub(struct fsg_lun *curlun)
1474 {
1475         struct file     *filp = curlun->filp;
1476         struct inode    *inode = filp->f_path.dentry->d_inode;
1477         unsigned long   rc;
1478
1479         rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1480         VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1481 }
1482
1483 static int do_verify(struct fsg_dev *fsg)
1484 {
1485         struct fsg_lun          *curlun = fsg->curlun;
1486         u32                     lba;
1487         u32                     verification_length;
1488         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
1489         loff_t                  file_offset, file_offset_tmp;
1490         u32                     amount_left;
1491         unsigned int            amount;
1492         ssize_t                 nread;
1493
1494         /* Get the starting Logical Block Address and check that it's
1495          * not too big */
1496         lba = get_unaligned_be32(&fsg->cmnd[2]);
1497         if (lba >= curlun->num_sectors) {
1498                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1499                 return -EINVAL;
1500         }
1501
1502         /* We allow DPO (Disable Page Out = don't save data in the
1503          * cache) but we don't implement it. */
1504         if ((fsg->cmnd[1] & ~0x10) != 0) {
1505                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1506                 return -EINVAL;
1507         }
1508
1509         verification_length = get_unaligned_be16(&fsg->cmnd[7]);
1510         if (unlikely(verification_length == 0))
1511                 return -EIO;            // No default reply
1512
1513         /* Prepare to carry out the file verify */
1514         amount_left = verification_length << curlun->blkbits;
1515         file_offset = ((loff_t) lba) << curlun->blkbits;
1516
1517         /* Write out all the dirty buffers before invalidating them */
1518         fsg_lun_fsync_sub(curlun);
1519         if (signal_pending(current))
1520                 return -EINTR;
1521
1522         invalidate_sub(curlun);
1523         if (signal_pending(current))
1524                 return -EINTR;
1525
1526         /* Just try to read the requested blocks */
1527         while (amount_left > 0) {
1528
1529                 /* Figure out how much we need to read:
1530                  * Try to read the remaining amount, but not more than
1531                  * the buffer size.
1532                  * And don't try to read past the end of the file.
1533                  */
1534                 amount = min((unsigned int) amount_left, mod_data.buflen);
1535                 amount = min((loff_t) amount,
1536                                 curlun->file_length - file_offset);
1537                 if (amount == 0) {
1538                         curlun->sense_data =
1539                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1540                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1541                         curlun->info_valid = 1;
1542                         break;
1543                 }
1544
1545                 /* Perform the read */
1546                 file_offset_tmp = file_offset;
1547                 nread = vfs_read(curlun->filp,
1548                                 (char __user *) bh->buf,
1549                                 amount, &file_offset_tmp);
1550                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1551                                 (unsigned long long) file_offset,
1552                                 (int) nread);
1553                 if (signal_pending(current))
1554                         return -EINTR;
1555
1556                 if (nread < 0) {
1557                         LDBG(curlun, "error in file verify: %d\n",
1558                                         (int) nread);
1559                         nread = 0;
1560                 } else if (nread < amount) {
1561                         LDBG(curlun, "partial file verify: %d/%u\n",
1562                                         (int) nread, amount);
1563                         nread = round_down(nread, curlun->blksize);
1564                 }
1565                 if (nread == 0) {
1566                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1567                         curlun->sense_data_info = file_offset >> curlun->blkbits;
1568                         curlun->info_valid = 1;
1569                         break;
1570                 }
1571                 file_offset += nread;
1572                 amount_left -= nread;
1573         }
1574         return 0;
1575 }
1576
1577
1578 /*-------------------------------------------------------------------------*/
1579
1580 static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1581 {
1582         u8      *buf = (u8 *) bh->buf;
1583
1584         static char vendor_id[] = "Linux   ";
1585         static char product_disk_id[] = "File-Stor Gadget";
1586         static char product_cdrom_id[] = "File-CD Gadget  ";
1587
1588         if (!fsg->curlun) {             // Unsupported LUNs are okay
1589                 fsg->bad_lun_okay = 1;
1590                 memset(buf, 0, 36);
1591                 buf[0] = 0x7f;          // Unsupported, no device-type
1592                 buf[4] = 31;            // Additional length
1593                 return 36;
1594         }
1595
1596         memset(buf, 0, 8);
1597         buf[0] = (mod_data.cdrom ? TYPE_ROM : TYPE_DISK);
1598         if (mod_data.removable)
1599                 buf[1] = 0x80;
1600         buf[2] = 2;             // ANSI SCSI level 2
1601         buf[3] = 2;             // SCSI-2 INQUIRY data format
1602         buf[4] = 31;            // Additional length
1603                                 // No special options
1604         sprintf(buf + 8, "%-8s%-16s%04x", vendor_id,
1605                         (mod_data.cdrom ? product_cdrom_id :
1606                                 product_disk_id),
1607                         mod_data.release);
1608         return 36;
1609 }
1610
1611
1612 static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1613 {
1614         struct fsg_lun  *curlun = fsg->curlun;
1615         u8              *buf = (u8 *) bh->buf;
1616         u32             sd, sdinfo;
1617         int             valid;
1618
1619         /*
1620          * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1621          *
1622          * If a REQUEST SENSE command is received from an initiator
1623          * with a pending unit attention condition (before the target
1624          * generates the contingent allegiance condition), then the
1625          * target shall either:
1626          *   a) report any pending sense data and preserve the unit
1627          *      attention condition on the logical unit, or,
1628          *   b) report the unit attention condition, may discard any
1629          *      pending sense data, and clear the unit attention
1630          *      condition on the logical unit for that initiator.
1631          *
1632          * FSG normally uses option a); enable this code to use option b).
1633          */
1634 #if 0
1635         if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1636                 curlun->sense_data = curlun->unit_attention_data;
1637                 curlun->unit_attention_data = SS_NO_SENSE;
1638         }
1639 #endif
1640
1641         if (!curlun) {          // Unsupported LUNs are okay
1642                 fsg->bad_lun_okay = 1;
1643                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1644                 sdinfo = 0;
1645                 valid = 0;
1646         } else {
1647                 sd = curlun->sense_data;
1648                 sdinfo = curlun->sense_data_info;
1649                 valid = curlun->info_valid << 7;
1650                 curlun->sense_data = SS_NO_SENSE;
1651                 curlun->sense_data_info = 0;
1652                 curlun->info_valid = 0;
1653         }
1654
1655         memset(buf, 0, 18);
1656         buf[0] = valid | 0x70;                  // Valid, current error
1657         buf[2] = SK(sd);
1658         put_unaligned_be32(sdinfo, &buf[3]);    /* Sense information */
1659         buf[7] = 18 - 8;                        // Additional sense length
1660         buf[12] = ASC(sd);
1661         buf[13] = ASCQ(sd);
1662         return 18;
1663 }
1664
1665
1666 static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1667 {
1668         struct fsg_lun  *curlun = fsg->curlun;
1669         u32             lba = get_unaligned_be32(&fsg->cmnd[2]);
1670         int             pmi = fsg->cmnd[8];
1671         u8              *buf = (u8 *) bh->buf;
1672
1673         /* Check the PMI and LBA fields */
1674         if (pmi > 1 || (pmi == 0 && lba != 0)) {
1675                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1676                 return -EINVAL;
1677         }
1678
1679         put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1680                                                 /* Max logical block */
1681         put_unaligned_be32(curlun->blksize, &buf[4]);   /* Block length */
1682         return 8;
1683 }
1684
1685
1686 static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1687 {
1688         struct fsg_lun  *curlun = fsg->curlun;
1689         int             msf = fsg->cmnd[1] & 0x02;
1690         u32             lba = get_unaligned_be32(&fsg->cmnd[2]);
1691         u8              *buf = (u8 *) bh->buf;
1692
1693         if ((fsg->cmnd[1] & ~0x02) != 0) {              /* Mask away MSF */
1694                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1695                 return -EINVAL;
1696         }
1697         if (lba >= curlun->num_sectors) {
1698                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1699                 return -EINVAL;
1700         }
1701
1702         memset(buf, 0, 8);
1703         buf[0] = 0x01;          /* 2048 bytes of user data, rest is EC */
1704         store_cdrom_address(&buf[4], msf, lba);
1705         return 8;
1706 }
1707
1708
1709 static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1710 {
1711         struct fsg_lun  *curlun = fsg->curlun;
1712         int             msf = fsg->cmnd[1] & 0x02;
1713         int             start_track = fsg->cmnd[6];
1714         u8              *buf = (u8 *) bh->buf;
1715
1716         if ((fsg->cmnd[1] & ~0x02) != 0 ||              /* Mask away MSF */
1717                         start_track > 1) {
1718                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1719                 return -EINVAL;
1720         }
1721
1722         memset(buf, 0, 20);
1723         buf[1] = (20-2);                /* TOC data length */
1724         buf[2] = 1;                     /* First track number */
1725         buf[3] = 1;                     /* Last track number */
1726         buf[5] = 0x16;                  /* Data track, copying allowed */
1727         buf[6] = 0x01;                  /* Only track is number 1 */
1728         store_cdrom_address(&buf[8], msf, 0);
1729
1730         buf[13] = 0x16;                 /* Lead-out track is data */
1731         buf[14] = 0xAA;                 /* Lead-out track number */
1732         store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1733         return 20;
1734 }
1735
1736
1737 static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1738 {
1739         struct fsg_lun  *curlun = fsg->curlun;
1740         int             mscmnd = fsg->cmnd[0];
1741         u8              *buf = (u8 *) bh->buf;
1742         u8              *buf0 = buf;
1743         int             pc, page_code;
1744         int             changeable_values, all_pages;
1745         int             valid_page = 0;
1746         int             len, limit;
1747
1748         if ((fsg->cmnd[1] & ~0x08) != 0) {              // Mask away DBD
1749                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1750                 return -EINVAL;
1751         }
1752         pc = fsg->cmnd[2] >> 6;
1753         page_code = fsg->cmnd[2] & 0x3f;
1754         if (pc == 3) {
1755                 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1756                 return -EINVAL;
1757         }
1758         changeable_values = (pc == 1);
1759         all_pages = (page_code == 0x3f);
1760
1761         /* Write the mode parameter header.  Fixed values are: default
1762          * medium type, no cache control (DPOFUA), and no block descriptors.
1763          * The only variable value is the WriteProtect bit.  We will fill in
1764          * the mode data length later. */
1765         memset(buf, 0, 8);
1766         if (mscmnd == MODE_SENSE) {
1767                 buf[2] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
1768                 buf += 4;
1769                 limit = 255;
1770         } else {                        // MODE_SENSE_10
1771                 buf[3] = (curlun->ro ? 0x80 : 0x00);            // WP, DPOFUA
1772                 buf += 8;
1773                 limit = 65535;          // Should really be mod_data.buflen
1774         }
1775
1776         /* No block descriptors */
1777
1778         /* The mode pages, in numerical order.  The only page we support
1779          * is the Caching page. */
1780         if (page_code == 0x08 || all_pages) {
1781                 valid_page = 1;
1782                 buf[0] = 0x08;          // Page code
1783                 buf[1] = 10;            // Page length
1784                 memset(buf+2, 0, 10);   // None of the fields are changeable
1785
1786                 if (!changeable_values) {
1787                         buf[2] = 0x04;  // Write cache enable,
1788                                         // Read cache not disabled
1789                                         // No cache retention priorities
1790                         put_unaligned_be16(0xffff, &buf[4]);
1791                                         /* Don't disable prefetch */
1792                                         /* Minimum prefetch = 0 */
1793                         put_unaligned_be16(0xffff, &buf[8]);
1794                                         /* Maximum prefetch */
1795                         put_unaligned_be16(0xffff, &buf[10]);
1796                                         /* Maximum prefetch ceiling */
1797                 }
1798                 buf += 12;
1799         }
1800
1801         /* Check that a valid page was requested and the mode data length
1802          * isn't too long. */
1803         len = buf - buf0;
1804         if (!valid_page || len > limit) {
1805                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1806                 return -EINVAL;
1807         }
1808
1809         /*  Store the mode data length */
1810         if (mscmnd == MODE_SENSE)
1811                 buf0[0] = len - 1;
1812         else
1813                 put_unaligned_be16(len - 2, buf0);
1814         return len;
1815 }
1816
1817
1818 static int do_start_stop(struct fsg_dev *fsg)
1819 {
1820         struct fsg_lun  *curlun = fsg->curlun;
1821         int             loej, start;
1822
1823         if (!mod_data.removable) {
1824                 curlun->sense_data = SS_INVALID_COMMAND;
1825                 return -EINVAL;
1826         }
1827
1828         // int immed = fsg->cmnd[1] & 0x01;
1829         loej = fsg->cmnd[4] & 0x02;
1830         start = fsg->cmnd[4] & 0x01;
1831
1832 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1833         if ((fsg->cmnd[1] & ~0x01) != 0 ||              // Mask away Immed
1834                         (fsg->cmnd[4] & ~0x03) != 0) {  // Mask LoEj, Start
1835                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1836                 return -EINVAL;
1837         }
1838
1839         if (!start) {
1840
1841                 /* Are we allowed to unload the media? */
1842                 if (curlun->prevent_medium_removal) {
1843                         LDBG(curlun, "unload attempt prevented\n");
1844                         curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1845                         return -EINVAL;
1846                 }
1847                 if (loej) {             // Simulate an unload/eject
1848                         up_read(&fsg->filesem);
1849                         down_write(&fsg->filesem);
1850                         fsg_lun_close(curlun);
1851                         up_write(&fsg->filesem);
1852                         down_read(&fsg->filesem);
1853                 }
1854         } else {
1855
1856                 /* Our emulation doesn't support mounting; the medium is
1857                  * available for use as soon as it is loaded. */
1858                 if (!fsg_lun_is_open(curlun)) {
1859                         curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1860                         return -EINVAL;
1861                 }
1862         }
1863 #endif
1864         return 0;
1865 }
1866
1867
1868 static int do_prevent_allow(struct fsg_dev *fsg)
1869 {
1870         struct fsg_lun  *curlun = fsg->curlun;
1871         int             prevent;
1872
1873         if (!mod_data.removable) {
1874                 curlun->sense_data = SS_INVALID_COMMAND;
1875                 return -EINVAL;
1876         }
1877
1878         prevent = fsg->cmnd[4] & 0x01;
1879         if ((fsg->cmnd[4] & ~0x01) != 0) {              // Mask away Prevent
1880                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1881                 return -EINVAL;
1882         }
1883
1884         if (curlun->prevent_medium_removal && !prevent)
1885                 fsg_lun_fsync_sub(curlun);
1886         curlun->prevent_medium_removal = prevent;
1887         return 0;
1888 }
1889
1890
1891 static int do_read_format_capacities(struct fsg_dev *fsg,
1892                         struct fsg_buffhd *bh)
1893 {
1894         struct fsg_lun  *curlun = fsg->curlun;
1895         u8              *buf = (u8 *) bh->buf;
1896
1897         buf[0] = buf[1] = buf[2] = 0;
1898         buf[3] = 8;             // Only the Current/Maximum Capacity Descriptor
1899         buf += 4;
1900
1901         put_unaligned_be32(curlun->num_sectors, &buf[0]);
1902                                                 /* Number of blocks */
1903         put_unaligned_be32(curlun->blksize, &buf[4]);   /* Block length */
1904         buf[4] = 0x02;                          /* Current capacity */
1905         return 12;
1906 }
1907
1908
1909 static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1910 {
1911         struct fsg_lun  *curlun = fsg->curlun;
1912
1913         /* We don't support MODE SELECT */
1914         curlun->sense_data = SS_INVALID_COMMAND;
1915         return -EINVAL;
1916 }
1917
1918
1919 /*-------------------------------------------------------------------------*/
1920
1921 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1922 {
1923         int     rc;
1924
1925         rc = fsg_set_halt(fsg, fsg->bulk_in);
1926         if (rc == -EAGAIN)
1927                 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1928         while (rc != 0) {
1929                 if (rc != -EAGAIN) {
1930                         WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1931                         rc = 0;
1932                         break;
1933                 }
1934
1935                 /* Wait for a short time and then try again */
1936                 if (msleep_interruptible(100) != 0)
1937                         return -EINTR;
1938                 rc = usb_ep_set_halt(fsg->bulk_in);
1939         }
1940         return rc;
1941 }
1942
1943 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1944 {
1945         int     rc;
1946
1947         DBG(fsg, "bulk-in set wedge\n");
1948         rc = usb_ep_set_wedge(fsg->bulk_in);
1949         if (rc == -EAGAIN)
1950                 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1951         while (rc != 0) {
1952                 if (rc != -EAGAIN) {
1953                         WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1954                         rc = 0;
1955                         break;
1956                 }
1957
1958                 /* Wait for a short time and then try again */
1959                 if (msleep_interruptible(100) != 0)
1960                         return -EINTR;
1961                 rc = usb_ep_set_wedge(fsg->bulk_in);
1962         }
1963         return rc;
1964 }
1965
1966 static int throw_away_data(struct fsg_dev *fsg)
1967 {
1968         struct fsg_buffhd       *bh;
1969         u32                     amount;
1970         int                     rc;
1971
1972         while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY ||
1973                         fsg->usb_amount_left > 0) {
1974
1975                 /* Throw away the data in a filled buffer */
1976                 if (bh->state == BUF_STATE_FULL) {
1977                         smp_rmb();
1978                         bh->state = BUF_STATE_EMPTY;
1979                         fsg->next_buffhd_to_drain = bh->next;
1980
1981                         /* A short packet or an error ends everything */
1982                         if (bh->outreq->actual < bh->bulk_out_intended_length ||
1983                                         bh->outreq->status != 0) {
1984                                 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
1985                                 return -EINTR;
1986                         }
1987                         continue;
1988                 }
1989
1990                 /* Try to submit another request if we need one */
1991                 bh = fsg->next_buffhd_to_fill;
1992                 if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
1993                         amount = min(fsg->usb_amount_left,
1994                                         (u32) mod_data.buflen);
1995
1996                         /* Except at the end of the transfer, amount will be
1997                          * equal to the buffer size, which is divisible by
1998                          * the bulk-out maxpacket size.
1999                          */
2000                         set_bulk_out_req_length(fsg, bh, amount);
2001                         start_transfer(fsg, fsg->bulk_out, bh->outreq,
2002                                         &bh->outreq_busy, &bh->state);
2003                         fsg->next_buffhd_to_fill = bh->next;
2004                         fsg->usb_amount_left -= amount;
2005                         continue;
2006                 }
2007
2008                 /* Otherwise wait for something to happen */
2009                 rc = sleep_thread(fsg);
2010                 if (rc)
2011                         return rc;
2012         }
2013         return 0;
2014 }
2015
2016
2017 static int finish_reply(struct fsg_dev *fsg)
2018 {
2019         struct fsg_buffhd       *bh = fsg->next_buffhd_to_fill;
2020         int                     rc = 0;
2021
2022         switch (fsg->data_dir) {
2023         case DATA_DIR_NONE:
2024                 break;                  // Nothing to send
2025
2026         /* If we don't know whether the host wants to read or write,
2027          * this must be CB or CBI with an unknown command.  We mustn't
2028          * try to send or receive any data.  So stall both bulk pipes
2029          * if we can and wait for a reset. */
2030         case DATA_DIR_UNKNOWN:
2031                 if (mod_data.can_stall) {
2032                         fsg_set_halt(fsg, fsg->bulk_out);
2033                         rc = halt_bulk_in_endpoint(fsg);
2034                 }
2035                 break;
2036
2037         /* All but the last buffer of data must have already been sent */
2038         case DATA_DIR_TO_HOST:
2039                 if (fsg->data_size == 0)
2040                         ;               // Nothing to send
2041
2042                 /* If there's no residue, simply send the last buffer */
2043                 else if (fsg->residue == 0) {
2044                         bh->inreq->zero = 0;
2045                         start_transfer(fsg, fsg->bulk_in, bh->inreq,
2046                                         &bh->inreq_busy, &bh->state);
2047                         fsg->next_buffhd_to_fill = bh->next;
2048                 }
2049
2050                 /* There is a residue.  For CB and CBI, simply mark the end
2051                  * of the data with a short packet.  However, if we are
2052                  * allowed to stall, there was no data at all (residue ==
2053                  * data_size), and the command failed (invalid LUN or
2054                  * sense data is set), then halt the bulk-in endpoint
2055                  * instead. */
2056                 else if (!transport_is_bbb()) {
2057                         if (mod_data.can_stall &&
2058                                         fsg->residue == fsg->data_size &&
2059         (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) {
2060                                 bh->state = BUF_STATE_EMPTY;
2061                                 rc = halt_bulk_in_endpoint(fsg);
2062                         } else {
2063                                 bh->inreq->zero = 1;
2064                                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2065                                                 &bh->inreq_busy, &bh->state);
2066                                 fsg->next_buffhd_to_fill = bh->next;
2067                         }
2068                 }
2069
2070                 /*
2071                  * For Bulk-only, mark the end of the data with a short
2072                  * packet.  If we are allowed to stall, halt the bulk-in
2073                  * endpoint.  (Note: This violates the Bulk-Only Transport
2074                  * specification, which requires us to pad the data if we
2075                  * don't halt the endpoint.  Presumably nobody will mind.)
2076                  */
2077                 else {
2078                         bh->inreq->zero = 1;
2079                         start_transfer(fsg, fsg->bulk_in, bh->inreq,
2080                                         &bh->inreq_busy, &bh->state);
2081                         fsg->next_buffhd_to_fill = bh->next;
2082                         if (mod_data.can_stall)
2083                                 rc = halt_bulk_in_endpoint(fsg);
2084                 }
2085                 break;
2086
2087         /* We have processed all we want from the data the host has sent.
2088          * There may still be outstanding bulk-out requests. */
2089         case DATA_DIR_FROM_HOST:
2090                 if (fsg->residue == 0)
2091                         ;               // Nothing to receive
2092
2093                 /* Did the host stop sending unexpectedly early? */
2094                 else if (fsg->short_packet_received) {
2095                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2096                         rc = -EINTR;
2097                 }
2098
2099                 /* We haven't processed all the incoming data.  Even though
2100                  * we may be allowed to stall, doing so would cause a race.
2101                  * The controller may already have ACK'ed all the remaining
2102                  * bulk-out packets, in which case the host wouldn't see a
2103                  * STALL.  Not realizing the endpoint was halted, it wouldn't
2104                  * clear the halt -- leading to problems later on. */
2105 #if 0
2106                 else if (mod_data.can_stall) {
2107                         fsg_set_halt(fsg, fsg->bulk_out);
2108                         raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2109                         rc = -EINTR;
2110                 }
2111 #endif
2112
2113                 /* We can't stall.  Read in the excess data and throw it
2114                  * all away. */
2115                 else
2116                         rc = throw_away_data(fsg);
2117                 break;
2118         }
2119         return rc;
2120 }
2121
2122
2123 static int send_status(struct fsg_dev *fsg)
2124 {
2125         struct fsg_lun          *curlun = fsg->curlun;
2126         struct fsg_buffhd       *bh;
2127         int                     rc;
2128         u8                      status = US_BULK_STAT_OK;
2129         u32                     sd, sdinfo = 0;
2130
2131         /* Wait for the next buffer to become available */
2132         bh = fsg->next_buffhd_to_fill;
2133         while (bh->state != BUF_STATE_EMPTY) {
2134                 rc = sleep_thread(fsg);
2135                 if (rc)
2136                         return rc;
2137         }
2138
2139         if (curlun) {
2140                 sd = curlun->sense_data;
2141                 sdinfo = curlun->sense_data_info;
2142         } else if (fsg->bad_lun_okay)
2143                 sd = SS_NO_SENSE;
2144         else
2145                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2146
2147         if (fsg->phase_error) {
2148                 DBG(fsg, "sending phase-error status\n");
2149                 status = US_BULK_STAT_PHASE;
2150                 sd = SS_INVALID_COMMAND;
2151         } else if (sd != SS_NO_SENSE) {
2152                 DBG(fsg, "sending command-failure status\n");
2153                 status = US_BULK_STAT_FAIL;
2154                 VDBG(fsg, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
2155                                 "  info x%x\n",
2156                                 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
2157         }
2158
2159         if (transport_is_bbb()) {
2160                 struct bulk_cs_wrap     *csw = bh->buf;
2161
2162                 /* Store and send the Bulk-only CSW */
2163                 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
2164                 csw->Tag = fsg->tag;
2165                 csw->Residue = cpu_to_le32(fsg->residue);
2166                 csw->Status = status;
2167
2168                 bh->inreq->length = US_BULK_CS_WRAP_LEN;
2169                 bh->inreq->zero = 0;
2170                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2171                                 &bh->inreq_busy, &bh->state);
2172
2173         } else if (mod_data.transport_type == USB_PR_CB) {
2174
2175                 /* Control-Bulk transport has no status phase! */
2176                 return 0;
2177
2178         } else {                        // USB_PR_CBI
2179                 struct interrupt_data   *buf = bh->buf;
2180
2181                 /* Store and send the Interrupt data.  UFI sends the ASC
2182                  * and ASCQ bytes.  Everything else sends a Type (which
2183                  * is always 0) and the status Value. */
2184                 if (mod_data.protocol_type == USB_SC_UFI) {
2185                         buf->bType = ASC(sd);
2186                         buf->bValue = ASCQ(sd);
2187                 } else {
2188                         buf->bType = 0;
2189                         buf->bValue = status;
2190                 }
2191                 fsg->intreq->length = CBI_INTERRUPT_DATA_LEN;
2192
2193                 fsg->intr_buffhd = bh;          // Point to the right buffhd
2194                 fsg->intreq->buf = bh->inreq->buf;
2195                 fsg->intreq->context = bh;
2196                 start_transfer(fsg, fsg->intr_in, fsg->intreq,
2197                                 &fsg->intreq_busy, &bh->state);
2198         }
2199
2200         fsg->next_buffhd_to_fill = bh->next;
2201         return 0;
2202 }
2203
2204
2205 /*-------------------------------------------------------------------------*/
2206
2207 /* Check whether the command is properly formed and whether its data size
2208  * and direction agree with the values we already have. */
2209 static int check_command(struct fsg_dev *fsg, int cmnd_size,
2210                 enum data_direction data_dir, unsigned int mask,
2211                 int needs_medium, const char *name)
2212 {
2213         int                     i;
2214         int                     lun = fsg->cmnd[1] >> 5;
2215         static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
2216         char                    hdlen[20];
2217         struct fsg_lun          *curlun;
2218
2219         /* Adjust the expected cmnd_size for protocol encapsulation padding.
2220          * Transparent SCSI doesn't pad. */
2221         if (protocol_is_scsi())
2222                 ;
2223
2224         /* There's some disagreement as to whether RBC pads commands or not.
2225          * We'll play it safe and accept either form. */
2226         else if (mod_data.protocol_type == USB_SC_RBC) {
2227                 if (fsg->cmnd_size == 12)
2228                         cmnd_size = 12;
2229
2230         /* All the other protocols pad to 12 bytes */
2231         } else
2232                 cmnd_size = 12;
2233
2234         hdlen[0] = 0;
2235         if (fsg->data_dir != DATA_DIR_UNKNOWN)
2236                 sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
2237                                 fsg->data_size);
2238         VDBG(fsg, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
2239                         name, cmnd_size, dirletter[(int) data_dir],
2240                         fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen);
2241
2242         /* We can't reply at all until we know the correct data direction
2243          * and size. */
2244         if (fsg->data_size_from_cmnd == 0)
2245                 data_dir = DATA_DIR_NONE;
2246         if (fsg->data_dir == DATA_DIR_UNKNOWN) {        // CB or CBI
2247                 fsg->data_dir = data_dir;
2248                 fsg->data_size = fsg->data_size_from_cmnd;
2249
2250         } else {                                        // Bulk-only
2251                 if (fsg->data_size < fsg->data_size_from_cmnd) {
2252
2253                         /* Host data size < Device data size is a phase error.
2254                          * Carry out the command, but only transfer as much
2255                          * as we are allowed. */
2256                         fsg->data_size_from_cmnd = fsg->data_size;
2257                         fsg->phase_error = 1;
2258                 }
2259         }
2260         fsg->residue = fsg->usb_amount_left = fsg->data_size;
2261
2262         /* Conflicting data directions is a phase error */
2263         if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
2264                 fsg->phase_error = 1;
2265                 return -EINVAL;
2266         }
2267
2268         /* Verify the length of the command itself */
2269         if (cmnd_size != fsg->cmnd_size) {
2270
2271                 /* Special case workaround: There are plenty of buggy SCSI
2272                  * implementations. Many have issues with cbw->Length
2273                  * field passing a wrong command size. For those cases we
2274                  * always try to work around the problem by using the length
2275                  * sent by the host side provided it is at least as large
2276                  * as the correct command length.
2277                  * Examples of such cases would be MS-Windows, which issues
2278                  * REQUEST SENSE with cbw->Length == 12 where it should
2279                  * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
2280                  * REQUEST SENSE with cbw->Length == 10 where it should
2281                  * be 6 as well.
2282                  */
2283                 if (cmnd_size <= fsg->cmnd_size) {
2284                         DBG(fsg, "%s is buggy! Expected length %d "
2285                                         "but we got %d\n", name,
2286                                         cmnd_size, fsg->cmnd_size);
2287                         cmnd_size = fsg->cmnd_size;
2288                 } else {
2289                         fsg->phase_error = 1;
2290                         return -EINVAL;
2291                 }
2292         }
2293
2294         /* Check that the LUN values are consistent */
2295         if (transport_is_bbb()) {
2296                 if (fsg->lun != lun)
2297                         DBG(fsg, "using LUN %d from CBW, "
2298                                         "not LUN %d from CDB\n",
2299                                         fsg->lun, lun);
2300         }
2301
2302         /* Check the LUN */
2303         curlun = fsg->curlun;
2304         if (curlun) {
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->bad_lun_okay = 0;
2312
2313                 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
2314                  * to use unsupported LUNs; all others may not. */
2315                 if (fsg->cmnd[0] != INQUIRY &&
2316                                 fsg->cmnd[0] != REQUEST_SENSE) {
2317                         DBG(fsg, "unsupported LUN %d\n", fsg->lun);
2318                         return -EINVAL;
2319                 }
2320         }
2321
2322         /* If a unit attention condition exists, only INQUIRY and
2323          * REQUEST SENSE commands are allowed; anything else must fail. */
2324         if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
2325                         fsg->cmnd[0] != INQUIRY &&
2326                         fsg->cmnd[0] != REQUEST_SENSE) {
2327                 curlun->sense_data = curlun->unit_attention_data;
2328                 curlun->unit_attention_data = SS_NO_SENSE;
2329                 return -EINVAL;
2330         }
2331
2332         /* Check that only command bytes listed in the mask are non-zero */
2333         fsg->cmnd[1] &= 0x1f;                   // Mask away the LUN
2334         for (i = 1; i < cmnd_size; ++i) {
2335                 if (fsg->cmnd[i] && !(mask & (1 << i))) {
2336                         if (curlun)
2337                                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2338                         return -EINVAL;
2339                 }
2340         }
2341
2342         /* If the medium isn't mounted and the command needs to access
2343          * it, return an error. */
2344         if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
2345                 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2346                 return -EINVAL;
2347         }
2348
2349         return 0;
2350 }
2351
2352 /* wrapper of check_command for data size in blocks handling */
2353 static int check_command_size_in_blocks(struct fsg_dev *fsg, int cmnd_size,
2354                 enum data_direction data_dir, unsigned int mask,
2355                 int needs_medium, const char *name)
2356 {
2357         if (fsg->curlun)
2358                 fsg->data_size_from_cmnd <<= fsg->curlun->blkbits;
2359         return check_command(fsg, cmnd_size, data_dir,
2360                         mask, needs_medium, name);
2361 }
2362
2363 static int do_scsi_command(struct fsg_dev *fsg)
2364 {
2365         struct fsg_buffhd       *bh;
2366         int                     rc;
2367         int                     reply = -EINVAL;
2368         int                     i;
2369         static char             unknown[16];
2370
2371         dump_cdb(fsg);
2372
2373         /* Wait for the next buffer to become available for data or status */
2374         bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill;
2375         while (bh->state != BUF_STATE_EMPTY) {
2376                 rc = sleep_thread(fsg);
2377                 if (rc)
2378                         return rc;
2379         }
2380         fsg->phase_error = 0;
2381         fsg->short_packet_received = 0;
2382
2383         down_read(&fsg->filesem);       // We're using the backing file
2384         switch (fsg->cmnd[0]) {
2385
2386         case INQUIRY:
2387                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2388                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2389                                 (1<<4), 0,
2390                                 "INQUIRY")) == 0)
2391                         reply = do_inquiry(fsg, bh);
2392                 break;
2393
2394         case MODE_SELECT:
2395                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2396                 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2397                                 (1<<1) | (1<<4), 0,
2398                                 "MODE SELECT(6)")) == 0)
2399                         reply = do_mode_select(fsg, bh);
2400                 break;
2401
2402         case MODE_SELECT_10:
2403                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2404                 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2405                                 (1<<1) | (3<<7), 0,
2406                                 "MODE SELECT(10)")) == 0)
2407                         reply = do_mode_select(fsg, bh);
2408                 break;
2409
2410         case MODE_SENSE:
2411                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2412                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2413                                 (1<<1) | (1<<2) | (1<<4), 0,
2414                                 "MODE SENSE(6)")) == 0)
2415                         reply = do_mode_sense(fsg, bh);
2416                 break;
2417
2418         case MODE_SENSE_10:
2419                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2420                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2421                                 (1<<1) | (1<<2) | (3<<7), 0,
2422                                 "MODE SENSE(10)")) == 0)
2423                         reply = do_mode_sense(fsg, bh);
2424                 break;
2425
2426         case ALLOW_MEDIUM_REMOVAL:
2427                 fsg->data_size_from_cmnd = 0;
2428                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2429                                 (1<<4), 0,
2430                                 "PREVENT-ALLOW MEDIUM REMOVAL")) == 0)
2431                         reply = do_prevent_allow(fsg);
2432                 break;
2433
2434         case READ_6:
2435                 i = fsg->cmnd[4];
2436                 fsg->data_size_from_cmnd = (i == 0) ? 256 : i;
2437                 if ((reply = check_command_size_in_blocks(fsg, 6,
2438                                 DATA_DIR_TO_HOST,
2439                                 (7<<1) | (1<<4), 1,
2440                                 "READ(6)")) == 0)
2441                         reply = do_read(fsg);
2442                 break;
2443
2444         case READ_10:
2445                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2446                 if ((reply = check_command_size_in_blocks(fsg, 10,
2447                                 DATA_DIR_TO_HOST,
2448                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2449                                 "READ(10)")) == 0)
2450                         reply = do_read(fsg);
2451                 break;
2452
2453         case READ_12:
2454                 fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->cmnd[6]);
2455                 if ((reply = check_command_size_in_blocks(fsg, 12,
2456                                 DATA_DIR_TO_HOST,
2457                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2458                                 "READ(12)")) == 0)
2459                         reply = do_read(fsg);
2460                 break;
2461
2462         case READ_CAPACITY:
2463                 fsg->data_size_from_cmnd = 8;
2464                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2465                                 (0xf<<2) | (1<<8), 1,
2466                                 "READ CAPACITY")) == 0)
2467                         reply = do_read_capacity(fsg, bh);
2468                 break;
2469
2470         case READ_HEADER:
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                                 (3<<7) | (0x1f<<1), 1,
2476                                 "READ HEADER")) == 0)
2477                         reply = do_read_header(fsg, bh);
2478                 break;
2479
2480         case READ_TOC:
2481                 if (!mod_data.cdrom)
2482                         goto unknown_cmnd;
2483                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2484                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2485                                 (7<<6) | (1<<1), 1,
2486                                 "READ TOC")) == 0)
2487                         reply = do_read_toc(fsg, bh);
2488                 break;
2489
2490         case READ_FORMAT_CAPACITIES:
2491                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2492                 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2493                                 (3<<7), 1,
2494                                 "READ FORMAT CAPACITIES")) == 0)
2495                         reply = do_read_format_capacities(fsg, bh);
2496                 break;
2497
2498         case REQUEST_SENSE:
2499                 fsg->data_size_from_cmnd = fsg->cmnd[4];
2500                 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2501                                 (1<<4), 0,
2502                                 "REQUEST SENSE")) == 0)
2503                         reply = do_request_sense(fsg, bh);
2504                 break;
2505
2506         case START_STOP:
2507                 fsg->data_size_from_cmnd = 0;
2508                 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2509                                 (1<<1) | (1<<4), 0,
2510                                 "START-STOP UNIT")) == 0)
2511                         reply = do_start_stop(fsg);
2512                 break;
2513
2514         case SYNCHRONIZE_CACHE:
2515                 fsg->data_size_from_cmnd = 0;
2516                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2517                                 (0xf<<2) | (3<<7), 1,
2518                                 "SYNCHRONIZE CACHE")) == 0)
2519                         reply = do_synchronize_cache(fsg);
2520                 break;
2521
2522         case TEST_UNIT_READY:
2523                 fsg->data_size_from_cmnd = 0;
2524                 reply = check_command(fsg, 6, DATA_DIR_NONE,
2525                                 0, 1,
2526                                 "TEST UNIT READY");
2527                 break;
2528
2529         /* Although optional, this command is used by MS-Windows.  We
2530          * support a minimal version: BytChk must be 0. */
2531         case VERIFY:
2532                 fsg->data_size_from_cmnd = 0;
2533                 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2534                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2535                                 "VERIFY")) == 0)
2536                         reply = do_verify(fsg);
2537                 break;
2538
2539         case WRITE_6:
2540                 i = fsg->cmnd[4];
2541                 fsg->data_size_from_cmnd = (i == 0) ? 256 : i;
2542                 if ((reply = check_command_size_in_blocks(fsg, 6,
2543                                 DATA_DIR_FROM_HOST,
2544                                 (7<<1) | (1<<4), 1,
2545                                 "WRITE(6)")) == 0)
2546                         reply = do_write(fsg);
2547                 break;
2548
2549         case WRITE_10:
2550                 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]);
2551                 if ((reply = check_command_size_in_blocks(fsg, 10,
2552                                 DATA_DIR_FROM_HOST,
2553                                 (1<<1) | (0xf<<2) | (3<<7), 1,
2554                                 "WRITE(10)")) == 0)
2555                         reply = do_write(fsg);
2556                 break;
2557
2558         case WRITE_12:
2559                 fsg->data_size_from_cmnd = get_unaligned_be32(&fsg->cmnd[6]);
2560                 if ((reply = check_command_size_in_blocks(fsg, 12,
2561                                 DATA_DIR_FROM_HOST,
2562                                 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2563                                 "WRITE(12)")) == 0)
2564                         reply = do_write(fsg);
2565                 break;
2566
2567         /* Some mandatory commands that we recognize but don't implement.
2568          * They don't mean much in this setting.  It's left as an exercise
2569          * for anyone interested to implement RESERVE and RELEASE in terms
2570          * of Posix locks. */
2571         case FORMAT_UNIT:
2572         case RELEASE:
2573         case RESERVE:
2574         case SEND_DIAGNOSTIC:
2575                 // Fall through
2576
2577         default:
2578  unknown_cmnd:
2579                 fsg->data_size_from_cmnd = 0;
2580                 sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]);
2581                 if ((reply = check_command(fsg, fsg->cmnd_size,
2582                                 DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) {
2583                         fsg->curlun->sense_data = SS_INVALID_COMMAND;
2584                         reply = -EINVAL;
2585                 }
2586                 break;
2587         }
2588         up_read(&fsg->filesem);
2589
2590         if (reply == -EINTR || signal_pending(current))
2591                 return -EINTR;
2592
2593         /* Set up the single reply buffer for finish_reply() */
2594         if (reply == -EINVAL)
2595                 reply = 0;              // Error reply length
2596         if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
2597                 reply = min((u32) reply, fsg->data_size_from_cmnd);
2598                 bh->inreq->length = reply;
2599                 bh->state = BUF_STATE_FULL;
2600                 fsg->residue -= reply;
2601         }                               // Otherwise it's already set
2602
2603         return 0;
2604 }
2605
2606
2607 /*-------------------------------------------------------------------------*/
2608
2609 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2610 {
2611         struct usb_request              *req = bh->outreq;
2612         struct bulk_cb_wrap     *cbw = req->buf;
2613
2614         /* Was this a real packet?  Should it be ignored? */
2615         if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2616                 return -EINVAL;
2617
2618         /* Is the CBW valid? */
2619         if (req->actual != US_BULK_CB_WRAP_LEN ||
2620                         cbw->Signature != cpu_to_le32(
2621                                 US_BULK_CB_SIGN)) {
2622                 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2623                                 req->actual,
2624                                 le32_to_cpu(cbw->Signature));
2625
2626                 /* The Bulk-only spec says we MUST stall the IN endpoint
2627                  * (6.6.1), so it's unavoidable.  It also says we must
2628                  * retain this state until the next reset, but there's
2629                  * no way to tell the controller driver it should ignore
2630                  * Clear-Feature(HALT) requests.
2631                  *
2632                  * We aren't required to halt the OUT endpoint; instead
2633                  * we can simply accept and discard any data received
2634                  * until the next reset. */
2635                 wedge_bulk_in_endpoint(fsg);
2636                 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2637                 return -EINVAL;
2638         }
2639
2640         /* Is the CBW meaningful? */
2641         if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2642                         cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2643                 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2644                                 "cmdlen %u\n",
2645                                 cbw->Lun, cbw->Flags, cbw->Length);
2646
2647                 /* We can do anything we want here, so let's stall the
2648                  * bulk pipes if we are allowed to. */
2649                 if (mod_data.can_stall) {
2650                         fsg_set_halt(fsg, fsg->bulk_out);
2651                         halt_bulk_in_endpoint(fsg);
2652                 }
2653                 return -EINVAL;
2654         }
2655
2656         /* Save the command for later */
2657         fsg->cmnd_size = cbw->Length;
2658         memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size);
2659         if (cbw->Flags & US_BULK_FLAG_IN)
2660                 fsg->data_dir = DATA_DIR_TO_HOST;
2661         else
2662                 fsg->data_dir = DATA_DIR_FROM_HOST;
2663         fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
2664         if (fsg->data_size == 0)
2665                 fsg->data_dir = DATA_DIR_NONE;
2666         fsg->lun = cbw->Lun;
2667         fsg->tag = cbw->Tag;
2668         return 0;
2669 }
2670
2671
2672 static int get_next_command(struct fsg_dev *fsg)
2673 {
2674         struct fsg_buffhd       *bh;
2675         int                     rc = 0;
2676
2677         if (transport_is_bbb()) {
2678
2679                 /* Wait for the next buffer to become available */
2680                 bh = fsg->next_buffhd_to_fill;
2681                 while (bh->state != BUF_STATE_EMPTY) {
2682                         rc = sleep_thread(fsg);
2683                         if (rc)
2684                                 return rc;
2685                 }
2686
2687                 /* Queue a request to read a Bulk-only CBW */
2688                 set_bulk_out_req_length(fsg, bh, US_BULK_CB_WRAP_LEN);
2689                 start_transfer(fsg, fsg->bulk_out, bh->outreq,
2690                                 &bh->outreq_busy, &bh->state);
2691
2692                 /* We will drain the buffer in software, which means we
2693                  * can reuse it for the next filling.  No need to advance
2694                  * next_buffhd_to_fill. */
2695
2696                 /* Wait for the CBW to arrive */
2697                 while (bh->state != BUF_STATE_FULL) {
2698                         rc = sleep_thread(fsg);
2699                         if (rc)
2700                                 return rc;
2701                 }
2702                 smp_rmb();
2703                 rc = received_cbw(fsg, bh);
2704                 bh->state = BUF_STATE_EMPTY;
2705
2706         } else {                // USB_PR_CB or USB_PR_CBI
2707
2708                 /* Wait for the next command to arrive */
2709                 while (fsg->cbbuf_cmnd_size == 0) {
2710                         rc = sleep_thread(fsg);
2711                         if (rc)
2712                                 return rc;
2713                 }
2714
2715                 /* Is the previous status interrupt request still busy?
2716                  * The host is allowed to skip reading the status,
2717                  * so we must cancel it. */
2718                 if (fsg->intreq_busy)
2719                         usb_ep_dequeue(fsg->intr_in, fsg->intreq);
2720
2721                 /* Copy the command and mark the buffer empty */
2722                 fsg->data_dir = DATA_DIR_UNKNOWN;
2723                 spin_lock_irq(&fsg->lock);
2724                 fsg->cmnd_size = fsg->cbbuf_cmnd_size;
2725                 memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size);
2726                 fsg->cbbuf_cmnd_size = 0;
2727                 spin_unlock_irq(&fsg->lock);
2728
2729                 /* Use LUN from the command */
2730                 fsg->lun = fsg->cmnd[1] >> 5;
2731         }
2732
2733         /* Update current lun */
2734         if (fsg->lun >= 0 && fsg->lun < fsg->nluns)
2735                 fsg->curlun = &fsg->luns[fsg->lun];
2736         else
2737                 fsg->curlun = NULL;
2738
2739         return rc;
2740 }
2741
2742
2743 /*-------------------------------------------------------------------------*/
2744
2745 static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
2746                 const struct usb_endpoint_descriptor *d)
2747 {
2748         int     rc;
2749
2750         ep->driver_data = fsg;
2751         ep->desc = d;
2752         rc = usb_ep_enable(ep);
2753         if (rc)
2754                 ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
2755         return rc;
2756 }
2757
2758 static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
2759                 struct usb_request **preq)
2760 {
2761         *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2762         if (*preq)
2763                 return 0;
2764         ERROR(fsg, "can't allocate request for %s\n", ep->name);
2765         return -ENOMEM;
2766 }
2767
2768 /*
2769  * Reset interface setting and re-init endpoint state (toggle etc).
2770  * Call with altsetting < 0 to disable the interface.  The only other
2771  * available altsetting is 0, which enables the interface.
2772  */
2773 static int do_set_interface(struct fsg_dev *fsg, int altsetting)
2774 {
2775         int     rc = 0;
2776         int     i;
2777         const struct usb_endpoint_descriptor    *d;
2778
2779         if (fsg->running)
2780                 DBG(fsg, "reset interface\n");
2781
2782 reset:
2783         /* Deallocate the requests */
2784         for (i = 0; i < fsg_num_buffers; ++i) {
2785                 struct fsg_buffhd *bh = &fsg->buffhds[i];
2786
2787                 if (bh->inreq) {
2788                         usb_ep_free_request(fsg->bulk_in, bh->inreq);
2789                         bh->inreq = NULL;
2790                 }
2791                 if (bh->outreq) {
2792                         usb_ep_free_request(fsg->bulk_out, bh->outreq);
2793                         bh->outreq = NULL;
2794                 }
2795         }
2796         if (fsg->intreq) {
2797                 usb_ep_free_request(fsg->intr_in, fsg->intreq);
2798                 fsg->intreq = NULL;
2799         }
2800
2801         /* Disable the endpoints */
2802         if (fsg->bulk_in_enabled) {
2803                 usb_ep_disable(fsg->bulk_in);
2804                 fsg->bulk_in_enabled = 0;
2805         }
2806         if (fsg->bulk_out_enabled) {
2807                 usb_ep_disable(fsg->bulk_out);
2808                 fsg->bulk_out_enabled = 0;
2809         }
2810         if (fsg->intr_in_enabled) {
2811                 usb_ep_disable(fsg->intr_in);
2812                 fsg->intr_in_enabled = 0;
2813         }
2814
2815         fsg->running = 0;
2816         if (altsetting < 0 || rc != 0)
2817                 return rc;
2818
2819         DBG(fsg, "set interface %d\n", altsetting);
2820
2821         /* Enable the endpoints */
2822         d = fsg_ep_desc(fsg->gadget,
2823                         &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc,
2824                         &fsg_ss_bulk_in_desc);
2825         if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
2826                 goto reset;
2827         fsg->bulk_in_enabled = 1;
2828
2829         d = fsg_ep_desc(fsg->gadget,
2830                         &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc,
2831                         &fsg_ss_bulk_out_desc);
2832         if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0)
2833                 goto reset;
2834         fsg->bulk_out_enabled = 1;
2835         fsg->bulk_out_maxpacket = usb_endpoint_maxp(d);
2836         clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2837
2838         if (transport_is_cbi()) {
2839                 d = fsg_ep_desc(fsg->gadget,
2840                                 &fsg_fs_intr_in_desc, &fsg_hs_intr_in_desc,
2841                                 &fsg_ss_intr_in_desc);
2842                 if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0)
2843                         goto reset;
2844                 fsg->intr_in_enabled = 1;
2845         }
2846
2847         /* Allocate the requests */
2848         for (i = 0; i < fsg_num_buffers; ++i) {
2849                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
2850
2851                 if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0)
2852                         goto reset;
2853                 if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0)
2854                         goto reset;
2855                 bh->inreq->buf = bh->outreq->buf = bh->buf;
2856                 bh->inreq->context = bh->outreq->context = bh;
2857                 bh->inreq->complete = bulk_in_complete;
2858                 bh->outreq->complete = bulk_out_complete;
2859         }
2860         if (transport_is_cbi()) {
2861                 if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0)
2862                         goto reset;
2863                 fsg->intreq->complete = intr_in_complete;
2864         }
2865
2866         fsg->running = 1;
2867         for (i = 0; i < fsg->nluns; ++i)
2868                 fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2869         return rc;
2870 }
2871
2872
2873 /*
2874  * Change our operational configuration.  This code must agree with the code
2875  * that returns config descriptors, and with interface altsetting code.
2876  *
2877  * It's also responsible for power management interactions.  Some
2878  * configurations might not work with our current power sources.
2879  * For now we just assume the gadget is always self-powered.
2880  */
2881 static int do_set_config(struct fsg_dev *fsg, u8 new_config)
2882 {
2883         int     rc = 0;
2884
2885         /* Disable the single interface */
2886         if (fsg->config != 0) {
2887                 DBG(fsg, "reset config\n");
2888                 fsg->config = 0;
2889                 rc = do_set_interface(fsg, -1);
2890         }
2891
2892         /* Enable the interface */
2893         if (new_config != 0) {
2894                 fsg->config = new_config;
2895                 if ((rc = do_set_interface(fsg, 0)) != 0)
2896                         fsg->config = 0;        // Reset on errors
2897                 else
2898                         INFO(fsg, "%s config #%d\n",
2899                              usb_speed_string(fsg->gadget->speed),
2900                              fsg->config);
2901         }
2902         return rc;
2903 }
2904
2905
2906 /*-------------------------------------------------------------------------*/
2907
2908 static void handle_exception(struct fsg_dev *fsg)
2909 {
2910         siginfo_t               info;
2911         int                     sig;
2912         int                     i;
2913         int                     num_active;
2914         struct fsg_buffhd       *bh;
2915         enum fsg_state          old_state;
2916         u8                      new_config;
2917         struct fsg_lun          *curlun;
2918         unsigned int            exception_req_tag;
2919         int                     rc;
2920
2921         /* Clear the existing signals.  Anything but SIGUSR1 is converted
2922          * into a high-priority EXIT exception. */
2923         for (;;) {
2924                 sig = dequeue_signal_lock(current, &current->blocked, &info);
2925                 if (!sig)
2926                         break;
2927                 if (sig != SIGUSR1) {
2928                         if (fsg->state < FSG_STATE_EXIT)
2929                                 DBG(fsg, "Main thread exiting on signal\n");
2930                         raise_exception(fsg, FSG_STATE_EXIT);
2931                 }
2932         }
2933
2934         /* Cancel all the pending transfers */
2935         if (fsg->intreq_busy)
2936                 usb_ep_dequeue(fsg->intr_in, fsg->intreq);
2937         for (i = 0; i < fsg_num_buffers; ++i) {
2938                 bh = &fsg->buffhds[i];
2939                 if (bh->inreq_busy)
2940                         usb_ep_dequeue(fsg->bulk_in, bh->inreq);
2941                 if (bh->outreq_busy)
2942                         usb_ep_dequeue(fsg->bulk_out, bh->outreq);
2943         }
2944
2945         /* Wait until everything is idle */
2946         for (;;) {
2947                 num_active = fsg->intreq_busy;
2948                 for (i = 0; i < fsg_num_buffers; ++i) {
2949                         bh = &fsg->buffhds[i];
2950                         num_active += bh->inreq_busy + bh->outreq_busy;
2951                 }
2952                 if (num_active == 0)
2953                         break;
2954                 if (sleep_thread(fsg))
2955                         return;
2956         }
2957
2958         /* Clear out the controller's fifos */
2959         if (fsg->bulk_in_enabled)
2960                 usb_ep_fifo_flush(fsg->bulk_in);
2961         if (fsg->bulk_out_enabled)
2962                 usb_ep_fifo_flush(fsg->bulk_out);
2963         if (fsg->intr_in_enabled)
2964                 usb_ep_fifo_flush(fsg->intr_in);
2965
2966         /* Reset the I/O buffer states and pointers, the SCSI
2967          * state, and the exception.  Then invoke the handler. */
2968         spin_lock_irq(&fsg->lock);
2969
2970         for (i = 0; i < fsg_num_buffers; ++i) {
2971                 bh = &fsg->buffhds[i];
2972                 bh->state = BUF_STATE_EMPTY;
2973         }
2974         fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain =
2975                         &fsg->buffhds[0];
2976
2977         exception_req_tag = fsg->exception_req_tag;
2978         new_config = fsg->new_config;
2979         old_state = fsg->state;
2980
2981         if (old_state == FSG_STATE_ABORT_BULK_OUT)
2982                 fsg->state = FSG_STATE_STATUS_PHASE;
2983         else {
2984                 for (i = 0; i < fsg->nluns; ++i) {
2985                         curlun = &fsg->luns[i];
2986                         curlun->prevent_medium_removal = 0;
2987                         curlun->sense_data = curlun->unit_attention_data =
2988                                         SS_NO_SENSE;
2989                         curlun->sense_data_info = 0;
2990                         curlun->info_valid = 0;
2991                 }
2992                 fsg->state = FSG_STATE_IDLE;
2993         }
2994         spin_unlock_irq(&fsg->lock);
2995
2996         /* Carry out any extra actions required for the exception */
2997         switch (old_state) {
2998         default:
2999                 break;
3000
3001         case FSG_STATE_ABORT_BULK_OUT:
3002                 send_status(fsg);
3003                 spin_lock_irq(&fsg->lock);
3004                 if (fsg->state == FSG_STATE_STATUS_PHASE)
3005                         fsg->state = FSG_STATE_IDLE;
3006                 spin_unlock_irq(&fsg->lock);
3007                 break;
3008
3009         case FSG_STATE_RESET:
3010                 /* In case we were forced against our will to halt a
3011                  * bulk endpoint, clear the halt now.  (The SuperH UDC
3012                  * requires this.) */
3013                 if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
3014                         usb_ep_clear_halt(fsg->bulk_in);
3015
3016                 if (transport_is_bbb()) {
3017                         if (fsg->ep0_req_tag == exception_req_tag)
3018                                 ep0_queue(fsg); // Complete the status stage
3019
3020                 } else if (transport_is_cbi())
3021                         send_status(fsg);       // Status by interrupt pipe
3022
3023                 /* Technically this should go here, but it would only be
3024                  * a waste of time.  Ditto for the INTERFACE_CHANGE and
3025                  * CONFIG_CHANGE cases. */
3026                 // for (i = 0; i < fsg->nluns; ++i)
3027                 //      fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3028                 break;
3029
3030         case FSG_STATE_INTERFACE_CHANGE:
3031                 rc = do_set_interface(fsg, 0);
3032                 if (fsg->ep0_req_tag != exception_req_tag)
3033                         break;
3034                 if (rc != 0)                    // STALL on errors
3035                         fsg_set_halt(fsg, fsg->ep0);
3036                 else                            // Complete the status stage
3037                         ep0_queue(fsg);
3038                 break;
3039
3040         case FSG_STATE_CONFIG_CHANGE:
3041                 rc = do_set_config(fsg, new_config);
3042                 if (fsg->ep0_req_tag != exception_req_tag)
3043                         break;
3044                 if (rc != 0)                    // STALL on errors
3045                         fsg_set_halt(fsg, fsg->ep0);
3046                 else                            // Complete the status stage
3047                         ep0_queue(fsg);
3048                 break;
3049
3050         case FSG_STATE_DISCONNECT:
3051                 for (i = 0; i < fsg->nluns; ++i)
3052                         fsg_lun_fsync_sub(fsg->luns + i);
3053                 do_set_config(fsg, 0);          // Unconfigured state
3054                 break;
3055
3056         case FSG_STATE_EXIT:
3057         case FSG_STATE_TERMINATED:
3058                 do_set_config(fsg, 0);                  // Free resources
3059                 spin_lock_irq(&fsg->lock);
3060                 fsg->state = FSG_STATE_TERMINATED;      // Stop the thread
3061                 spin_unlock_irq(&fsg->lock);
3062                 break;
3063         }
3064 }
3065
3066
3067 /*-------------------------------------------------------------------------*/
3068
3069 static int fsg_main_thread(void *fsg_)
3070 {
3071         struct fsg_dev          *fsg = fsg_;
3072
3073         /* Allow the thread to be killed by a signal, but set the signal mask
3074          * to block everything but INT, TERM, KILL, and USR1. */
3075         allow_signal(SIGINT);
3076         allow_signal(SIGTERM);
3077         allow_signal(SIGKILL);
3078         allow_signal(SIGUSR1);
3079
3080         /* Allow the thread to be frozen */
3081         set_freezable();
3082
3083         /* Arrange for userspace references to be interpreted as kernel
3084          * pointers.  That way we can pass a kernel pointer to a routine
3085          * that expects a __user pointer and it will work okay. */
3086         set_fs(get_ds());
3087
3088         /* The main loop */
3089         while (fsg->state != FSG_STATE_TERMINATED) {
3090                 if (exception_in_progress(fsg) || signal_pending(current)) {
3091                         handle_exception(fsg);
3092                         continue;
3093                 }
3094
3095                 if (!fsg->running) {
3096                         sleep_thread(fsg);
3097                         continue;
3098                 }
3099
3100                 if (get_next_command(fsg))
3101                         continue;
3102
3103                 spin_lock_irq(&fsg->lock);
3104                 if (!exception_in_progress(fsg))
3105                         fsg->state = FSG_STATE_DATA_PHASE;
3106                 spin_unlock_irq(&fsg->lock);
3107
3108                 if (do_scsi_command(fsg) || finish_reply(fsg))
3109                         continue;
3110
3111                 spin_lock_irq(&fsg->lock);
3112                 if (!exception_in_progress(fsg))
3113                         fsg->state = FSG_STATE_STATUS_PHASE;
3114                 spin_unlock_irq(&fsg->lock);
3115
3116                 if (send_status(fsg))
3117                         continue;
3118
3119                 spin_lock_irq(&fsg->lock);
3120                 if (!exception_in_progress(fsg))
3121                         fsg->state = FSG_STATE_IDLE;
3122                 spin_unlock_irq(&fsg->lock);
3123                 }
3124
3125         spin_lock_irq(&fsg->lock);
3126         fsg->thread_task = NULL;
3127         spin_unlock_irq(&fsg->lock);
3128
3129         /* If we are exiting because of a signal, unregister the
3130          * gadget driver. */
3131         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
3132                 usb_gadget_unregister_driver(&fsg_driver);
3133
3134         /* Let the unbind and cleanup routines know the thread has exited */
3135         complete_and_exit(&fsg->thread_notifier, 0);
3136 }
3137
3138
3139 /*-------------------------------------------------------------------------*/
3140
3141
3142 /* The write permissions and store_xxx pointers are set in fsg_bind() */
3143 static DEVICE_ATTR(ro, 0444, fsg_show_ro, NULL);
3144 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, NULL);
3145 static DEVICE_ATTR(file, 0444, fsg_show_file, NULL);
3146
3147
3148 /*-------------------------------------------------------------------------*/
3149
3150 static void fsg_release(struct kref *ref)
3151 {
3152         struct fsg_dev  *fsg = container_of(ref, struct fsg_dev, ref);
3153
3154         kfree(fsg->luns);
3155         kfree(fsg);
3156 }
3157
3158 static void lun_release(struct device *dev)
3159 {
3160         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
3161         struct fsg_dev          *fsg =
3162                 container_of(filesem, struct fsg_dev, filesem);
3163
3164         kref_put(&fsg->ref, fsg_release);
3165 }
3166
3167 static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
3168 {
3169         struct fsg_dev          *fsg = get_gadget_data(gadget);
3170         int                     i;
3171         struct fsg_lun          *curlun;
3172         struct usb_request      *req = fsg->ep0req;
3173
3174         DBG(fsg, "unbind\n");
3175         clear_bit(REGISTERED, &fsg->atomic_bitflags);
3176
3177         /* If the thread isn't already dead, tell it to exit now */
3178         if (fsg->state != FSG_STATE_TERMINATED) {
3179                 raise_exception(fsg, FSG_STATE_EXIT);
3180                 wait_for_completion(&fsg->thread_notifier);
3181
3182                 /* The cleanup routine waits for this completion also */
3183                 complete(&fsg->thread_notifier);
3184         }
3185
3186         /* Unregister the sysfs attribute files and the LUNs */
3187         for (i = 0; i < fsg->nluns; ++i) {
3188                 curlun = &fsg->luns[i];
3189                 if (curlun->registered) {
3190                         device_remove_file(&curlun->dev, &dev_attr_nofua);
3191                         device_remove_file(&curlun->dev, &dev_attr_ro);
3192                         device_remove_file(&curlun->dev, &dev_attr_file);
3193                         fsg_lun_close(curlun);
3194                         device_unregister(&curlun->dev);
3195                         curlun->registered = 0;
3196                 }
3197         }
3198
3199         /* Free the data buffers */
3200         for (i = 0; i < fsg_num_buffers; ++i)
3201                 kfree(fsg->buffhds[i].buf);
3202
3203         /* Free the request and buffer for endpoint 0 */
3204         if (req) {
3205                 kfree(req->buf);
3206                 usb_ep_free_request(fsg->ep0, req);
3207         }
3208
3209         set_gadget_data(gadget, NULL);
3210 }
3211
3212
3213 static int __init check_parameters(struct fsg_dev *fsg)
3214 {
3215         int     prot;
3216         int     gcnum;
3217
3218         /* Store the default values */
3219         mod_data.transport_type = USB_PR_BULK;
3220         mod_data.transport_name = "Bulk-only";
3221         mod_data.protocol_type = USB_SC_SCSI;
3222         mod_data.protocol_name = "Transparent SCSI";
3223
3224         /* Some peripheral controllers are known not to be able to
3225          * halt bulk endpoints correctly.  If one of them is present,
3226          * disable stalls.
3227          */
3228         if (gadget_is_at91(fsg->gadget))
3229                 mod_data.can_stall = 0;
3230
3231         if (mod_data.release == 0xffff) {       // Parameter wasn't set
3232                 gcnum = usb_gadget_controller_number(fsg->gadget);
3233                 if (gcnum >= 0)
3234                         mod_data.release = 0x0300 + gcnum;
3235                 else {
3236                         WARNING(fsg, "controller '%s' not recognized\n",
3237                                 fsg->gadget->name);
3238                         mod_data.release = 0x0399;
3239                 }
3240         }
3241
3242         prot = simple_strtol(mod_data.protocol_parm, NULL, 0);
3243
3244 #ifdef CONFIG_USB_FILE_STORAGE_TEST
3245         if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) {
3246                 ;               // Use default setting
3247         } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) {
3248                 mod_data.transport_type = USB_PR_CB;
3249                 mod_data.transport_name = "Control-Bulk";
3250         } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) {
3251                 mod_data.transport_type = USB_PR_CBI;
3252                 mod_data.transport_name = "Control-Bulk-Interrupt";
3253         } else {
3254                 ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm);
3255                 return -EINVAL;
3256         }
3257
3258         if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 ||
3259                         prot == USB_SC_SCSI) {
3260                 ;               // Use default setting
3261         } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 ||
3262                         prot == USB_SC_RBC) {
3263                 mod_data.protocol_type = USB_SC_RBC;
3264                 mod_data.protocol_name = "RBC";
3265         } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 ||
3266                         strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 ||
3267                         prot == USB_SC_8020) {
3268                 mod_data.protocol_type = USB_SC_8020;
3269                 mod_data.protocol_name = "8020i (ATAPI)";
3270         } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 ||
3271                         prot == USB_SC_QIC) {
3272                 mod_data.protocol_type = USB_SC_QIC;
3273                 mod_data.protocol_name = "QIC-157";
3274         } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 ||
3275                         prot == USB_SC_UFI) {
3276                 mod_data.protocol_type = USB_SC_UFI;
3277                 mod_data.protocol_name = "UFI";
3278         } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 ||
3279                         prot == USB_SC_8070) {
3280                 mod_data.protocol_type = USB_SC_8070;
3281                 mod_data.protocol_name = "8070i";
3282         } else {
3283                 ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm);
3284                 return -EINVAL;
3285         }
3286
3287         mod_data.buflen &= PAGE_CACHE_MASK;
3288         if (mod_data.buflen <= 0) {
3289                 ERROR(fsg, "invalid buflen\n");
3290                 return -ETOOSMALL;
3291         }
3292
3293 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
3294
3295         /* Serial string handling.
3296          * On a real device, the serial string would be loaded
3297          * from permanent storage. */
3298         if (mod_data.serial) {
3299                 const char *ch;
3300                 unsigned len = 0;
3301
3302                 /* Sanity check :
3303                  * The CB[I] specification limits the serial string to
3304                  * 12 uppercase hexadecimal characters.
3305                  * BBB need at least 12 uppercase hexadecimal characters,
3306                  * with a maximum of 126. */
3307                 for (ch = mod_data.serial; *ch; ++ch) {
3308                         ++len;
3309                         if ((*ch < '0' || *ch > '9') &&
3310                             (*ch < 'A' || *ch > 'F')) { /* not uppercase hex */
3311                                 WARNING(fsg,
3312                                         "Invalid serial string character: %c\n",
3313                                         *ch);
3314                                 goto no_serial;
3315                         }
3316                 }
3317                 if (len > 126 ||
3318                     (mod_data.transport_type == USB_PR_BULK && len < 12) ||
3319                     (mod_data.transport_type != USB_PR_BULK && len > 12)) {
3320                         WARNING(fsg, "Invalid serial string length!\n");
3321                         goto no_serial;
3322                 }
3323                 fsg_strings[FSG_STRING_SERIAL - 1].s = mod_data.serial;
3324         } else {
3325                 WARNING(fsg, "No serial-number string provided!\n");
3326  no_serial:
3327                 device_desc.iSerialNumber = 0;
3328         }
3329
3330         return 0;
3331 }
3332
3333
3334 static int __init fsg_bind(struct usb_gadget *gadget)
3335 {
3336         struct fsg_dev          *fsg = the_fsg;
3337         int                     rc;
3338         int                     i;
3339         struct fsg_lun          *curlun;
3340         struct usb_ep           *ep;
3341         struct usb_request      *req;
3342         char                    *pathbuf, *p;
3343
3344         fsg->gadget = gadget;
3345         set_gadget_data(gadget, fsg);
3346         fsg->ep0 = gadget->ep0;
3347         fsg->ep0->driver_data = fsg;
3348
3349         if ((rc = check_parameters(fsg)) != 0)
3350                 goto out;
3351
3352         if (mod_data.removable) {       // Enable the store_xxx attributes
3353                 dev_attr_file.attr.mode = 0644;
3354                 dev_attr_file.store = fsg_store_file;
3355                 if (!mod_data.cdrom) {
3356                         dev_attr_ro.attr.mode = 0644;
3357                         dev_attr_ro.store = fsg_store_ro;
3358                 }
3359         }
3360
3361         /* Only for removable media? */
3362         dev_attr_nofua.attr.mode = 0644;
3363         dev_attr_nofua.store = fsg_store_nofua;
3364
3365         /* Find out how many LUNs there should be */
3366         i = mod_data.nluns;
3367         if (i == 0)
3368                 i = max(mod_data.num_filenames, 1u);
3369         if (i > FSG_MAX_LUNS) {
3370                 ERROR(fsg, "invalid number of LUNs: %d\n", i);
3371                 rc = -EINVAL;
3372                 goto out;
3373         }
3374
3375         /* Create the LUNs, open their backing files, and register the
3376          * LUN devices in sysfs. */
3377         fsg->luns = kzalloc(i * sizeof(struct fsg_lun), GFP_KERNEL);
3378         if (!fsg->luns) {
3379                 rc = -ENOMEM;
3380                 goto out;
3381         }
3382         fsg->nluns = i;
3383
3384         for (i = 0; i < fsg->nluns; ++i) {
3385                 curlun = &fsg->luns[i];
3386                 curlun->cdrom = !!mod_data.cdrom;
3387                 curlun->ro = mod_data.cdrom || mod_data.ro[i];
3388                 curlun->initially_ro = curlun->ro;
3389                 curlun->removable = mod_data.removable;
3390                 curlun->nofua = mod_data.nofua[i];
3391                 curlun->dev.release = lun_release;
3392                 curlun->dev.parent = &gadget->dev;
3393                 curlun->dev.driver = &fsg_driver.driver;
3394                 dev_set_drvdata(&curlun->dev, &fsg->filesem);
3395                 dev_set_name(&curlun->dev,"%s-lun%d",
3396                              dev_name(&gadget->dev), i);
3397
3398                 kref_get(&fsg->ref);
3399                 rc = device_register(&curlun->dev);
3400                 if (rc) {
3401                         INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
3402                         put_device(&curlun->dev);
3403                         goto out;
3404                 }
3405                 curlun->registered = 1;
3406
3407                 rc = device_create_file(&curlun->dev, &dev_attr_ro);
3408                 if (rc)
3409                         goto out;
3410                 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
3411                 if (rc)
3412                         goto out;
3413                 rc = device_create_file(&curlun->dev, &dev_attr_file);
3414                 if (rc)
3415                         goto out;
3416
3417                 if (mod_data.file[i] && *mod_data.file[i]) {
3418                         rc = fsg_lun_open(curlun, mod_data.file[i]);
3419                         if (rc)
3420                                 goto out;
3421                 } else if (!mod_data.removable) {
3422                         ERROR(fsg, "no file given for LUN%d\n", i);
3423                         rc = -EINVAL;
3424                         goto out;
3425                 }
3426         }
3427
3428         /* Find all the endpoints we will use */
3429         usb_ep_autoconfig_reset(gadget);
3430         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3431         if (!ep)
3432                 goto autoconf_fail;
3433         ep->driver_data = fsg;          // claim the endpoint
3434         fsg->bulk_in = ep;
3435
3436         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3437         if (!ep)
3438                 goto autoconf_fail;
3439         ep->driver_data = fsg;          // claim the endpoint
3440         fsg->bulk_out = ep;
3441
3442         if (transport_is_cbi()) {
3443                 ep = usb_ep_autoconfig(gadget, &fsg_fs_intr_in_desc);
3444                 if (!ep)
3445                         goto autoconf_fail;
3446                 ep->driver_data = fsg;          // claim the endpoint
3447                 fsg->intr_in = ep;
3448         }
3449
3450         /* Fix up the descriptors */
3451         device_desc.idVendor = cpu_to_le16(mod_data.vendor);
3452         device_desc.idProduct = cpu_to_le16(mod_data.product);
3453         device_desc.bcdDevice = cpu_to_le16(mod_data.release);
3454
3455         i = (transport_is_cbi() ? 3 : 2);       // Number of endpoints
3456         fsg_intf_desc.bNumEndpoints = i;
3457         fsg_intf_desc.bInterfaceSubClass = mod_data.protocol_type;
3458         fsg_intf_desc.bInterfaceProtocol = mod_data.transport_type;
3459         fsg_fs_function[i + FSG_FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3460
3461         if (gadget_is_dualspeed(gadget)) {
3462                 fsg_hs_function[i + FSG_HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3463
3464                 /* Assume endpoint addresses are the same for both speeds */
3465                 fsg_hs_bulk_in_desc.bEndpointAddress =
3466                         fsg_fs_bulk_in_desc.bEndpointAddress;
3467                 fsg_hs_bulk_out_desc.bEndpointAddress =
3468                         fsg_fs_bulk_out_desc.bEndpointAddress;
3469                 fsg_hs_intr_in_desc.bEndpointAddress =
3470                         fsg_fs_intr_in_desc.bEndpointAddress;
3471         }
3472
3473         if (gadget_is_superspeed(gadget)) {
3474                 unsigned                max_burst;
3475
3476                 fsg_ss_function[i + FSG_SS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3477
3478                 /* Calculate bMaxBurst, we know packet size is 1024 */
3479                 max_burst = min_t(unsigned, mod_data.buflen / 1024, 15);
3480
3481                 /* Assume endpoint addresses are the same for both speeds */
3482                 fsg_ss_bulk_in_desc.bEndpointAddress =
3483                         fsg_fs_bulk_in_desc.bEndpointAddress;
3484                 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3485
3486                 fsg_ss_bulk_out_desc.bEndpointAddress =
3487                         fsg_fs_bulk_out_desc.bEndpointAddress;
3488                 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3489         }
3490
3491         if (gadget_is_otg(gadget))
3492                 fsg_otg_desc.bmAttributes |= USB_OTG_HNP;
3493
3494         rc = -ENOMEM;
3495
3496         /* Allocate the request and buffer for endpoint 0 */
3497         fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL);
3498         if (!req)
3499                 goto out;
3500         req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL);
3501         if (!req->buf)
3502                 goto out;
3503         req->complete = ep0_complete;
3504
3505         /* Allocate the data buffers */
3506         for (i = 0; i < fsg_num_buffers; ++i) {
3507                 struct fsg_buffhd       *bh = &fsg->buffhds[i];
3508
3509                 /* Allocate for the bulk-in endpoint.  We assume that
3510                  * the buffer will also work with the bulk-out (and
3511                  * interrupt-in) endpoint. */
3512                 bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL);
3513                 if (!bh->buf)
3514                         goto out;
3515                 bh->next = bh + 1;
3516         }
3517         fsg->buffhds[fsg_num_buffers - 1].next = &fsg->buffhds[0];
3518
3519         /* This should reflect the actual gadget power source */
3520         usb_gadget_set_selfpowered(gadget);
3521
3522         snprintf(fsg_string_manufacturer, sizeof fsg_string_manufacturer,
3523                         "%s %s with %s",
3524                         init_utsname()->sysname, init_utsname()->release,
3525                         gadget->name);
3526
3527         fsg->thread_task = kthread_create(fsg_main_thread, fsg,
3528                         "file-storage-gadget");
3529         if (IS_ERR(fsg->thread_task)) {
3530                 rc = PTR_ERR(fsg->thread_task);
3531                 goto out;
3532         }
3533
3534         INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
3535         INFO(fsg, "NOTE: This driver is deprecated.  "
3536                         "Consider using g_mass_storage instead.\n");
3537         INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
3538
3539         pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
3540         for (i = 0; i < fsg->nluns; ++i) {
3541                 curlun = &fsg->luns[i];
3542                 if (fsg_lun_is_open(curlun)) {
3543                         p = NULL;
3544                         if (pathbuf) {
3545                                 p = d_path(&curlun->filp->f_path,
3546                                            pathbuf, PATH_MAX);
3547                                 if (IS_ERR(p))
3548                                         p = NULL;
3549                         }
3550                         LINFO(curlun, "ro=%d, nofua=%d, file: %s\n",
3551                               curlun->ro, curlun->nofua, (p ? p : "(error)"));
3552                 }
3553         }
3554         kfree(pathbuf);
3555
3556         DBG(fsg, "transport=%s (x%02x)\n",
3557                         mod_data.transport_name, mod_data.transport_type);
3558         DBG(fsg, "protocol=%s (x%02x)\n",
3559                         mod_data.protocol_name, mod_data.protocol_type);
3560         DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n",
3561                         mod_data.vendor, mod_data.product, mod_data.release);
3562         DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n",
3563                         mod_data.removable, mod_data.can_stall,
3564                         mod_data.cdrom, mod_data.buflen);
3565         DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
3566
3567         set_bit(REGISTERED, &fsg->atomic_bitflags);
3568
3569         /* Tell the thread to start working */
3570         wake_up_process(fsg->thread_task);
3571         return 0;
3572
3573 autoconf_fail:
3574         ERROR(fsg, "unable to autoconfigure all endpoints\n");
3575         rc = -ENOTSUPP;
3576
3577 out:
3578         fsg->state = FSG_STATE_TERMINATED;      // The thread is dead
3579         fsg_unbind(gadget);
3580         complete(&fsg->thread_notifier);
3581         return rc;
3582 }
3583
3584
3585 /*-------------------------------------------------------------------------*/
3586
3587 static void fsg_suspend(struct usb_gadget *gadget)
3588 {
3589         struct fsg_dev          *fsg = get_gadget_data(gadget);
3590
3591         DBG(fsg, "suspend\n");
3592         set_bit(SUSPENDED, &fsg->atomic_bitflags);
3593 }
3594
3595 static void fsg_resume(struct usb_gadget *gadget)
3596 {
3597         struct fsg_dev          *fsg = get_gadget_data(gadget);
3598
3599         DBG(fsg, "resume\n");
3600         clear_bit(SUSPENDED, &fsg->atomic_bitflags);
3601 }
3602
3603
3604 /*-------------------------------------------------------------------------*/
3605
3606 static struct usb_gadget_driver         fsg_driver = {
3607         .max_speed      = USB_SPEED_SUPER,
3608         .function       = (char *) fsg_string_product,
3609         .unbind         = fsg_unbind,
3610         .disconnect     = fsg_disconnect,
3611         .setup          = fsg_setup,
3612         .suspend        = fsg_suspend,
3613         .resume         = fsg_resume,
3614
3615         .driver         = {
3616                 .name           = DRIVER_NAME,
3617                 .owner          = THIS_MODULE,
3618                 // .release = ...
3619                 // .suspend = ...
3620                 // .resume = ...
3621         },
3622 };
3623
3624
3625 static int __init fsg_alloc(void)
3626 {
3627         struct fsg_dev          *fsg;
3628
3629         fsg = kzalloc(sizeof *fsg +
3630                       fsg_num_buffers * sizeof *(fsg->buffhds), GFP_KERNEL);
3631
3632         if (!fsg)
3633                 return -ENOMEM;
3634         spin_lock_init(&fsg->lock);
3635         init_rwsem(&fsg->filesem);
3636         kref_init(&fsg->ref);
3637         init_completion(&fsg->thread_notifier);
3638
3639         the_fsg = fsg;
3640         return 0;
3641 }
3642
3643
3644 static int __init fsg_init(void)
3645 {
3646         int             rc;
3647         struct fsg_dev  *fsg;
3648
3649         rc = fsg_num_buffers_validate();
3650         if (rc != 0)
3651                 return rc;
3652
3653         if ((rc = fsg_alloc()) != 0)
3654                 return rc;
3655         fsg = the_fsg;
3656         if ((rc = usb_gadget_probe_driver(&fsg_driver, fsg_bind)) != 0)
3657                 kref_put(&fsg->ref, fsg_release);
3658         return rc;
3659 }
3660 module_init(fsg_init);
3661
3662
3663 static void __exit fsg_cleanup(void)
3664 {
3665         struct fsg_dev  *fsg = the_fsg;
3666
3667         /* Unregister the driver iff the thread hasn't already done so */
3668         if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
3669                 usb_gadget_unregister_driver(&fsg_driver);
3670
3671         /* Wait for the thread to finish up */
3672         wait_for_completion(&fsg->thread_notifier);
3673
3674         kref_put(&fsg->ref, fsg_release);
3675 }
3676 module_exit(fsg_cleanup);