drivers/usb/gadget/storage_common.c

   1 /*
   2  * storage_common.c -- Common definitions for mass storage functionality
   3  *
   4  * Copyright (C) 2003-2008 Alan Stern
   5  * Copyeight (C) 2009 Samsung Electronics
   6  * Author: Michal Nazarewicz (mina86@mina86.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14
  15 /*
  16  * This file requires the following identifiers used in USB strings to
  17  * be defined (each of type pointer to char):
  18  *  - fsg_string_manufacturer -- name of the manufacturer
  19  *  - fsg_string_product      -- name of the product
  20  *  - fsg_string_config       -- name of the configuration
  21  *  - fsg_string_interface    -- name of the interface
  22  * The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS
  23  * macro is defined prior to including this file.
  24  */
  25
  26 /*
  27  * When FSG_NO_INTR_EP is defined fsg_fs_intr_in_desc and
  28  * fsg_hs_intr_in_desc objects as well as
  29  * FSG_FS_FUNCTION_PRE_EP_ENTRIES and FSG_HS_FUNCTION_PRE_EP_ENTRIES
  30  * macros are not defined.
  31  *
  32  * When FSG_NO_DEVICE_STRINGS is defined FSG_STRING_MANUFACTURER,
  33  * FSG_STRING_PRODUCT, FSG_STRING_SERIAL and FSG_STRING_CONFIG are not
  34  * defined (as well as corresponding entries in string tables are
  35  * missing) and FSG_STRING_INTERFACE has value of zero.
  36  *
  37  * When FSG_NO_OTG is defined fsg_otg_desc won't be defined.
  38  */
  39
  40 /*
  41  * When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included
  42  * the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN
  43  * characters rather then a pointer to void.
  44  */
  45
  46 /*
  47  * When USB_GADGET_DEBUG_FILES is defined the module param num_buffers
  48  * sets the number of pipeline buffers (length of the fsg_buffhd array).
  49  * The valid range of num_buffers is: num >= 2 && num <= 4.
  50  */
  51
  52
  53 #include <linux/usb/storage.h>
  54 #include <scsi/scsi.h>
  55 #include <asm/unaligned.h>
  56
  57
  58 /*
  59  * Thanks to NetChip Technologies for donating this product ID.
  60  *
  61  * DO NOT REUSE THESE IDs with any other driver!!  Ever!!
  62  * Instead:  allocate your own, using normal USB-IF procedures.
  63  */
  64 #define FSG_VENDOR_ID   0x0525  /* NetChip */
  65 #define FSG_PRODUCT_ID  0xa4a5  /* Linux-USB File-backed Storage Gadget */
  66
  67
  68 /*-------------------------------------------------------------------------*/
  69
  70
  71 #ifndef DEBUG
  72 #undef VERBOSE_DEBUG
  73 #undef DUMP_MSGS
  74 #endif /* !DEBUG */
  75
  76 #ifdef VERBOSE_DEBUG
  77 #define VLDBG   LDBG
  78 #else
  79 #define VLDBG(lun, fmt, args...) do { } while (0)
  80 #endif /* VERBOSE_DEBUG */
  81
  82 #define LDBG(lun, fmt, args...)   dev_dbg (&(lun)->dev, fmt, ## args)
  83 #define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args)
  84 #define LWARN(lun, fmt, args...)  dev_warn(&(lun)->dev, fmt, ## args)
  85 #define LINFO(lun, fmt, args...)  dev_info(&(lun)->dev, fmt, ## args)
  86
  87 /*
  88  * Keep those macros in sync with those in
  89  * include/linux/usb/composite.h or else GCC will complain.  If they
  90  * are identical (the same names of arguments, white spaces in the
  91  * same places) GCC will allow redefinition otherwise (even if some
  92  * white space is removed or added) warning will be issued.
  93  *
  94  * Those macros are needed here because File Storage Gadget does not
  95  * include the composite.h header.  For composite gadgets those macros
  96  * are redundant since composite.h is included any way.
  97  *
  98  * One could check whether those macros are already defined (which
  99  * would indicate composite.h had been included) or not (which would
 100  * indicate we were in FSG) but this is not done because a warning is
 101  * desired if definitions here differ from the ones in composite.h.
 102  *
 103  * We want the definitions to match and be the same in File Storage
 104  * Gadget as well as Mass Storage Function (and so composite gadgets
 105  * using MSF).  If someone changes them in composite.h it will produce
 106  * a warning in this file when building MSF.
 107  */
 108 #define DBG(d, fmt, args...)     dev_dbg(&(d)->gadget->dev , fmt , ## args)
 109 #define VDBG(d, fmt, args...)    dev_vdbg(&(d)->gadget->dev , fmt , ## args)
 110 #define ERROR(d, fmt, args...)   dev_err(&(d)->gadget->dev , fmt , ## args)
 111 #define WARNING(d, fmt, args...) dev_warn(&(d)->gadget->dev , fmt , ## args)
 112 #define INFO(d, fmt, args...)    dev_info(&(d)->gadget->dev , fmt , ## args)
 113
 114
 115
 116 #ifdef DUMP_MSGS
 117
 118 #  define dump_msg(fsg, /* const char * */ label,                       \
 119                    /* const u8 * */ buf, /* unsigned */ length) do {    \
 120         if (length < 512) {                                             \
 121                 DBG(fsg, "%s, length %u:\n", label, length);            \
 122                 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,      \
 123                                16, 1, buf, length, 0);                  \
 124         }                                                               \
 125 } while (0)
 126
 127 #  define dump_cdb(fsg) do { } while (0)
 128
 129 #else
 130
 131 #  define dump_msg(fsg, /* const char * */ label, \
 132                    /* const u8 * */ buf, /* unsigned */ length) do { } while (0)
 133
 134 #  ifdef VERBOSE_DEBUG
 135
 136 #    define dump_cdb(fsg)                                               \
 137         print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,      \
 138                        16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0)         \
 139
 140 #  else
 141
 142 #    define dump_cdb(fsg) do { } while (0)
 143
 144 #  endif /* VERBOSE_DEBUG */
 145
 146 #endif /* DUMP_MSGS */
 147
 148 /*-------------------------------------------------------------------------*/
 149
 150 /* CBI Interrupt data structure */
 151 struct interrupt_data {
 152         u8      bType;
 153         u8      bValue;
 154 };
 155
 156 #define CBI_INTERRUPT_DATA_LEN          2
 157
 158 /* CBI Accept Device-Specific Command request */
 159 #define USB_CBI_ADSC_REQUEST            0x00
 160
 161
 162 /* Length of a SCSI Command Data Block */
 163 #define MAX_COMMAND_SIZE        16
 164
 165 /* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
 166 #define SS_NO_SENSE                             0
 167 #define SS_COMMUNICATION_FAILURE                0x040800
 168 #define SS_INVALID_COMMAND                      0x052000
 169 #define SS_INVALID_FIELD_IN_CDB                 0x052400
 170 #define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE   0x052100
 171 #define SS_LOGICAL_UNIT_NOT_SUPPORTED           0x052500
 172 #define SS_MEDIUM_NOT_PRESENT                   0x023a00
 173 #define SS_MEDIUM_REMOVAL_PREVENTED             0x055302
 174 #define SS_NOT_READY_TO_READY_TRANSITION        0x062800
 175 #define SS_RESET_OCCURRED                       0x062900
 176 #define SS_SAVING_PARAMETERS_NOT_SUPPORTED      0x053900
 177 #define SS_UNRECOVERED_READ_ERROR               0x031100
 178 #define SS_WRITE_ERROR                          0x030c02
 179 #define SS_WRITE_PROTECTED                      0x072700
 180
 181 #define SK(x)           ((u8) ((x) >> 16))      /* Sense Key byte, etc. */
 182 #define ASC(x)          ((u8) ((x) >> 8))
 183 #define ASCQ(x)         ((u8) (x))
 184
 185
 186 /*-------------------------------------------------------------------------*/
 187
 188
 189 struct fsg_lun {
 190         struct file     *filp;
 191         loff_t          file_length;
 192         loff_t          num_sectors;
 193
 194         unsigned int    initially_ro:1;
 195         unsigned int    ro:1;
 196         unsigned int    removable:1;
 197         unsigned int    cdrom:1;
 198         unsigned int    prevent_medium_removal:1;
 199         unsigned int    registered:1;
 200         unsigned int    info_valid:1;
 201         unsigned int    nofua:1;
 202
 203         u32             sense_data;
 204         u32             sense_data_info;
 205         u32             unit_attention_data;
 206
 207         unsigned int    blkbits;        /* Bits of logical block size of bound block device */
 208         unsigned int    blksize;        /* logical block size of bound block device */
 209         struct device   dev;
 210 };
 211
 212 #define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
 213
 214 static struct fsg_lun *fsg_lun_from_dev(struct device *dev)
 215 {
 216         return container_of(dev, struct fsg_lun, dev);
 217 }
 218
 219
 220 /* Big enough to hold our biggest descriptor */
 221 #define EP0_BUFSIZE     256
 222 #define DELAYED_STATUS  (EP0_BUFSIZE + 999)     /* An impossibly large value */
 223
 224 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
 225
 226 static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
 227 module_param_named(num_buffers, fsg_num_buffers, uint, S_IRUGO);
 228 MODULE_PARM_DESC(num_buffers, "Number of pipeline buffers");
 229
 230 #else
 231
 232 /*
 233  * Number of buffers we will use.
 234  * 2 is usually enough for good buffering pipeline
 235  */
 236 #define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
 237
 238 #endif /* CONFIG_USB_DEBUG */
 239
 240 /* check if fsg_num_buffers is within a valid range */
 241 static inline int fsg_num_buffers_validate(void)
 242 {
 243         if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
 244                 return 0;
 245         pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
 246                fsg_num_buffers, 2 ,4);
 247         return -EINVAL;
 248 }
 249
 250 /* Default size of buffer length. */
 251 #define FSG_BUFLEN      ((u32)16384)
 252
 253 /* Maximal number of LUNs supported in mass storage function */
 254 #define FSG_MAX_LUNS    8
 255
 256 enum fsg_buffer_state {
 257         BUF_STATE_EMPTY = 0,
 258         BUF_STATE_FULL,
 259         BUF_STATE_BUSY
 260 };
 261
 262 struct fsg_buffhd {
 263 #ifdef FSG_BUFFHD_STATIC_BUFFER
 264         char                            buf[FSG_BUFLEN];
 265 #else
 266         void                            *buf;
 267 #endif
 268         enum fsg_buffer_state           state;
 269         struct fsg_buffhd               *next;
 270
 271         /*
 272          * The NetChip 2280 is faster, and handles some protocol faults
 273          * better, if we don't submit any short bulk-out read requests.
 274          * So we will record the intended request length here.
 275          */
 276         unsigned int                    bulk_out_intended_length;
 277
 278         struct usb_request              *inreq;
 279         int                             inreq_busy;
 280         struct usb_request              *outreq;
 281         int                             outreq_busy;
 282 };
 283
 284 enum fsg_state {
 285         /* This one isn't used anywhere */
 286         FSG_STATE_COMMAND_PHASE = -10,
 287         FSG_STATE_DATA_PHASE,
 288         FSG_STATE_STATUS_PHASE,
 289
 290         FSG_STATE_IDLE = 0,
 291         FSG_STATE_ABORT_BULK_OUT,
 292         FSG_STATE_RESET,
 293         FSG_STATE_INTERFACE_CHANGE,
 294         FSG_STATE_CONFIG_CHANGE,
 295         FSG_STATE_DISCONNECT,
 296         FSG_STATE_EXIT,
 297         FSG_STATE_TERMINATED
 298 };
 299
 300 enum data_direction {
 301         DATA_DIR_UNKNOWN = 0,
 302         DATA_DIR_FROM_HOST,
 303         DATA_DIR_TO_HOST,
 304         DATA_DIR_NONE
 305 };
 306
 307
 308 /*-------------------------------------------------------------------------*/
 309
 310
 311 static inline u32 get_unaligned_be24(u8 *buf)
 312 {
 313         return 0xffffff & (u32) get_unaligned_be32(buf - 1);
 314 }
 315
 316
 317 /*-------------------------------------------------------------------------*/
 318
 319
 320 enum {
 321 #ifndef FSG_NO_DEVICE_STRINGS
 322         FSG_STRING_MANUFACTURER = 1,
 323         FSG_STRING_PRODUCT,
 324         FSG_STRING_SERIAL,
 325         FSG_STRING_CONFIG,
 326 #endif
 327         FSG_STRING_INTERFACE
 328 };
 329
 330
 331 #ifndef FSG_NO_OTG
 332 static struct usb_otg_descriptor
 333 fsg_otg_desc = {
 334         .bLength =              sizeof fsg_otg_desc,
 335         .bDescriptorType =      USB_DT_OTG,
 336
 337         .bmAttributes =         USB_OTG_SRP,
 338 };
 339 #endif
 340
 341 /* There is only one interface. */
 342
 343 static struct usb_interface_descriptor
 344 fsg_intf_desc = {
 345         .bLength =              sizeof fsg_intf_desc,
 346         .bDescriptorType =      USB_DT_INTERFACE,
 347
 348         .bNumEndpoints =        2,              /* Adjusted during fsg_bind() */
 349         .bInterfaceClass =      USB_CLASS_MASS_STORAGE,
 350         .bInterfaceSubClass =   USB_SC_SCSI,    /* Adjusted during fsg_bind() */
 351         .bInterfaceProtocol =   USB_PR_BULK,    /* Adjusted during fsg_bind() */
 352         .iInterface =           FSG_STRING_INTERFACE,
 353 };
 354
 355 /*
 356  * Three full-speed endpoint descriptors: bulk-in, bulk-out, and
 357  * interrupt-in.
 358  */
 359
 360 static struct usb_endpoint_descriptor
 361 fsg_fs_bulk_in_desc = {
 362         .bLength =              USB_DT_ENDPOINT_SIZE,
 363         .bDescriptorType =      USB_DT_ENDPOINT,
 364
 365         .bEndpointAddress =     USB_DIR_IN,
 366         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 367         /* wMaxPacketSize set by autoconfiguration */
 368 };
 369
 370 static struct usb_endpoint_descriptor
 371 fsg_fs_bulk_out_desc = {
 372         .bLength =              USB_DT_ENDPOINT_SIZE,
 373         .bDescriptorType =      USB_DT_ENDPOINT,
 374
 375         .bEndpointAddress =     USB_DIR_OUT,
 376         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 377         /* wMaxPacketSize set by autoconfiguration */
 378 };
 379
 380 #ifndef FSG_NO_INTR_EP
 381
 382 static struct usb_endpoint_descriptor
 383 fsg_fs_intr_in_desc = {
 384         .bLength =              USB_DT_ENDPOINT_SIZE,
 385         .bDescriptorType =      USB_DT_ENDPOINT,
 386
 387         .bEndpointAddress =     USB_DIR_IN,
 388         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 389         .wMaxPacketSize =       cpu_to_le16(2),
 390         .bInterval =            32,     /* frames -> 32 ms */
 391 };
 392
 393 #ifndef FSG_NO_OTG
 394 #  define FSG_FS_FUNCTION_PRE_EP_ENTRIES        2
 395 #else
 396 #  define FSG_FS_FUNCTION_PRE_EP_ENTRIES        1
 397 #endif
 398
 399 #endif
 400
 401 static struct usb_descriptor_header *fsg_fs_function[] = {
 402 #ifndef FSG_NO_OTG
 403         (struct usb_descriptor_header *) &fsg_otg_desc,
 404 #endif
 405         (struct usb_descriptor_header *) &fsg_intf_desc,
 406         (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
 407         (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
 408 #ifndef FSG_NO_INTR_EP
 409         (struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
 410 #endif
 411         NULL,
 412 };
 413
 414
 415 /*
 416  * USB 2.0 devices need to expose both high speed and full speed
 417  * descriptors, unless they only run at full speed.
 418  *
 419  * That means alternate endpoint descriptors (bigger packets)
 420  * and a "device qualifier" ... plus more construction options
 421  * for the configuration descriptor.
 422  */
 423 static struct usb_endpoint_descriptor
 424 fsg_hs_bulk_in_desc = {
 425         .bLength =              USB_DT_ENDPOINT_SIZE,
 426         .bDescriptorType =      USB_DT_ENDPOINT,
 427
 428         /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
 429         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 430         .wMaxPacketSize =       cpu_to_le16(512),
 431 };
 432
 433 static struct usb_endpoint_descriptor
 434 fsg_hs_bulk_out_desc = {
 435         .bLength =              USB_DT_ENDPOINT_SIZE,
 436         .bDescriptorType =      USB_DT_ENDPOINT,
 437
 438         /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
 439         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 440         .wMaxPacketSize =       cpu_to_le16(512),
 441         .bInterval =            1,      /* NAK every 1 uframe */
 442 };
 443
 444 #ifndef FSG_NO_INTR_EP
 445
 446 static struct usb_endpoint_descriptor
 447 fsg_hs_intr_in_desc = {
 448         .bLength =              USB_DT_ENDPOINT_SIZE,
 449         .bDescriptorType =      USB_DT_ENDPOINT,
 450
 451         /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
 452         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 453         .wMaxPacketSize =       cpu_to_le16(2),
 454         .bInterval =            9,      /* 2**(9-1) = 256 uframes -> 32 ms */
 455 };
 456
 457 #ifndef FSG_NO_OTG
 458 #  define FSG_HS_FUNCTION_PRE_EP_ENTRIES        2
 459 #else
 460 #  define FSG_HS_FUNCTION_PRE_EP_ENTRIES        1
 461 #endif
 462
 463 #endif
 464
 465 static struct usb_descriptor_header *fsg_hs_function[] = {
 466 #ifndef FSG_NO_OTG
 467         (struct usb_descriptor_header *) &fsg_otg_desc,
 468 #endif
 469         (struct usb_descriptor_header *) &fsg_intf_desc,
 470         (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
 471         (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
 472 #ifndef FSG_NO_INTR_EP
 473         (struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
 474 #endif
 475         NULL,
 476 };
 477
 478 static struct usb_endpoint_descriptor
 479 fsg_ss_bulk_in_desc = {
 480         .bLength =              USB_DT_ENDPOINT_SIZE,
 481         .bDescriptorType =      USB_DT_ENDPOINT,
 482
 483         /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
 484         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 485         .wMaxPacketSize =       cpu_to_le16(1024),
 486 };
 487
 488 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc = {
 489         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 490         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 491
 492         /*.bMaxBurst =          DYNAMIC, */
 493 };
 494
 495 static struct usb_endpoint_descriptor
 496 fsg_ss_bulk_out_desc = {
 497         .bLength =              USB_DT_ENDPOINT_SIZE,
 498         .bDescriptorType =      USB_DT_ENDPOINT,
 499
 500         /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
 501         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 502         .wMaxPacketSize =       cpu_to_le16(1024),
 503 };
 504
 505 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc = {
 506         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 507         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 508
 509         /*.bMaxBurst =          DYNAMIC, */
 510 };
 511
 512 #ifndef FSG_NO_INTR_EP
 513
 514 static struct usb_endpoint_descriptor
 515 fsg_ss_intr_in_desc = {
 516         .bLength =              USB_DT_ENDPOINT_SIZE,
 517         .bDescriptorType =      USB_DT_ENDPOINT,
 518
 519         /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
 520         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 521         .wMaxPacketSize =       cpu_to_le16(2),
 522         .bInterval =            9,      /* 2**(9-1) = 256 uframes -> 32 ms */
 523 };
 524
 525 static struct usb_ss_ep_comp_descriptor fsg_ss_intr_in_comp_desc = {
 526         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 527         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 528
 529         .wBytesPerInterval =    cpu_to_le16(2),
 530 };
 531
 532 #ifndef FSG_NO_OTG
 533 #  define FSG_SS_FUNCTION_PRE_EP_ENTRIES        2
 534 #else
 535 #  define FSG_SS_FUNCTION_PRE_EP_ENTRIES        1
 536 #endif
 537
 538 #endif
 539
 540 static __maybe_unused struct usb_ext_cap_descriptor fsg_ext_cap_desc = {
 541         .bLength =              USB_DT_USB_EXT_CAP_SIZE,
 542         .bDescriptorType =      USB_DT_DEVICE_CAPABILITY,
 543         .bDevCapabilityType =   USB_CAP_TYPE_EXT,
 544
 545         .bmAttributes =         cpu_to_le32(USB_LPM_SUPPORT),
 546 };
 547
 548 static __maybe_unused struct usb_ss_cap_descriptor fsg_ss_cap_desc = {
 549         .bLength =              USB_DT_USB_SS_CAP_SIZE,
 550         .bDescriptorType =      USB_DT_DEVICE_CAPABILITY,
 551         .bDevCapabilityType =   USB_SS_CAP_TYPE,
 552
 553         /* .bmAttributes = LTM is not supported yet */
 554
 555         .wSpeedSupported =      cpu_to_le16(USB_LOW_SPEED_OPERATION
 556                 | USB_FULL_SPEED_OPERATION
 557                 | USB_HIGH_SPEED_OPERATION
 558                 | USB_5GBPS_OPERATION),
 559         .bFunctionalitySupport = USB_LOW_SPEED_OPERATION,
 560         .bU1devExitLat =        USB_DEFAULT_U1_DEV_EXIT_LAT,
 561         .bU2DevExitLat =        cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT),
 562 };
 563
 564 static __maybe_unused struct usb_bos_descriptor fsg_bos_desc = {
 565         .bLength =              USB_DT_BOS_SIZE,
 566         .bDescriptorType =      USB_DT_BOS,
 567
 568         .wTotalLength =         cpu_to_le16(USB_DT_BOS_SIZE
 569                                 + USB_DT_USB_EXT_CAP_SIZE
 570                                 + USB_DT_USB_SS_CAP_SIZE),
 571
 572         .bNumDeviceCaps =       2,
 573 };
 574
 575 static struct usb_descriptor_header *fsg_ss_function[] = {
 576 #ifndef FSG_NO_OTG
 577         (struct usb_descriptor_header *) &fsg_otg_desc,
 578 #endif
 579         (struct usb_descriptor_header *) &fsg_intf_desc,
 580         (struct usb_descriptor_header *) &fsg_ss_bulk_in_desc,
 581         (struct usb_descriptor_header *) &fsg_ss_bulk_in_comp_desc,
 582         (struct usb_descriptor_header *) &fsg_ss_bulk_out_desc,
 583         (struct usb_descriptor_header *) &fsg_ss_bulk_out_comp_desc,
 584 #ifndef FSG_NO_INTR_EP
 585         (struct usb_descriptor_header *) &fsg_ss_intr_in_desc,
 586         (struct usb_descriptor_header *) &fsg_ss_intr_in_comp_desc,
 587 #endif
 588         NULL,
 589 };
 590
 591 /* Maxpacket and other transfer characteristics vary by speed. */
 592 static __maybe_unused struct usb_endpoint_descriptor *
 593 fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
 594                 struct usb_endpoint_descriptor *hs,
 595                 struct usb_endpoint_descriptor *ss)
 596 {
 597         if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
 598                 return ss;
 599         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 600                 return hs;
 601         return fs;
 602 }
 603
 604
 605 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
 606 static struct usb_string                fsg_strings[] = {
 607 #ifndef FSG_NO_DEVICE_STRINGS
 608         {FSG_STRING_MANUFACTURER,       fsg_string_manufacturer},
 609         {FSG_STRING_PRODUCT,            fsg_string_product},
 610         {FSG_STRING_SERIAL,             ""},
 611         {FSG_STRING_CONFIG,             fsg_string_config},
 612 #endif
 613         {FSG_STRING_INTERFACE,          fsg_string_interface},
 614         {}
 615 };
 616
 617 static struct usb_gadget_strings        fsg_stringtab = {
 618         .language       = 0x0409,               /* en-us */
 619         .strings        = fsg_strings,
 620 };
 621
 622
 623  /*-------------------------------------------------------------------------*/
 624
 625 /*
 626  * If the next two routines are called while the gadget is registered,
 627  * the caller must own fsg->filesem for writing.
 628  */
 629
 630 static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
 631 {
 632         int                             ro;
 633         struct file                     *filp = NULL;
 634         int                             rc = -EINVAL;
 635         struct inode                    *inode = NULL;
 636         loff_t                          size;
 637         loff_t                          num_sectors;
 638         loff_t                          min_sectors;
 639
 640         /* R/W if we can, R/O if we must */
 641         ro = curlun->initially_ro;
 642         if (!ro) {
 643                 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
 644                 if (PTR_ERR(filp) == -EROFS || PTR_ERR(filp) == -EACCES)
 645                         ro = 1;
 646         }
 647         if (ro)
 648                 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
 649         if (IS_ERR(filp)) {
 650                 LINFO(curlun, "unable to open backing file: %s\n", filename);
 651                 return PTR_ERR(filp);
 652         }
 653
 654         if (!(filp->f_mode & FMODE_WRITE))
 655                 ro = 1;
 656
 657         if (filp->f_path.dentry)
 658                 inode = filp->f_path.dentry->d_inode;
 659         if (!inode || (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))) {
 660                 LINFO(curlun, "invalid file type: %s\n", filename);
 661                 goto out;
 662         }
 663
 664         /*
 665          * If we can't read the file, it's no good.
 666          * If we can't write the file, use it read-only.
 667          */
 668         if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
 669                 LINFO(curlun, "file not readable: %s\n", filename);
 670                 goto out;
 671         }
 672         if (!(filp->f_op->write || filp->f_op->aio_write))
 673                 ro = 1;
 674
 675         size = i_size_read(inode->i_mapping->host);
 676         if (size < 0) {
 677                 LINFO(curlun, "unable to find file size: %s\n", filename);
 678                 rc = (int) size;
 679                 goto out;
 680         }
 681
 682         if (curlun->cdrom) {
 683                 curlun->blksize = 2048;
 684                 curlun->blkbits = 11;
 685         } else if (inode->i_bdev) {
 686                 curlun->blksize = bdev_logical_block_size(inode->i_bdev);
 687                 curlun->blkbits = blksize_bits(curlun->blksize);
 688         } else {
 689                 curlun->blksize = 512;
 690                 curlun->blkbits = 9;
 691         }
 692
 693         num_sectors = size >> curlun->blkbits; /* File size in logic-block-size blocks */
 694         min_sectors = 1;
 695         if (curlun->cdrom) {
 696                 min_sectors = 300;      /* Smallest track is 300 frames */
 697                 if (num_sectors >= 256*60*75) {
 698                         num_sectors = 256*60*75 - 1;
 699                         LINFO(curlun, "file too big: %s\n", filename);
 700                         LINFO(curlun, "using only first %d blocks\n",
 701                                         (int) num_sectors);
 702                 }
 703         }
 704         if (num_sectors < min_sectors) {
 705                 LINFO(curlun, "file too small: %s\n", filename);
 706                 rc = -ETOOSMALL;
 707                 goto out;
 708         }
 709
 710         get_file(filp);
 711         curlun->ro = ro;
 712         curlun->filp = filp;
 713         curlun->file_length = size;
 714         curlun->num_sectors = num_sectors;
 715         LDBG(curlun, "open backing file: %s\n", filename);
 716         rc = 0;
 717
 718 out:
 719         filp_close(filp, current->files);
 720         return rc;
 721 }
 722
 723
 724 static void fsg_lun_close(struct fsg_lun *curlun)
 725 {
 726         if (curlun->filp) {
 727                 LDBG(curlun, "close backing file\n");
 728                 fput(curlun->filp);
 729                 curlun->filp = NULL;
 730         }
 731 }
 732
 733
 734 /*-------------------------------------------------------------------------*/
 735
 736 /*
 737  * Sync the file data, don't bother with the metadata.
 738  * This code was copied from fs/buffer.c:sys_fdatasync().
 739  */
 740 static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
 741 {
 742         struct file     *filp = curlun->filp;
 743
 744         if (curlun->ro || !filp)
 745                 return 0;
 746         return vfs_fsync(filp, 1);
 747 }
 748
 749 static void store_cdrom_address(u8 *dest, int msf, u32 addr)
 750 {
 751         if (msf) {
 752                 /* Convert to Minutes-Seconds-Frames */
 753                 addr >>= 2;             /* Convert to 2048-byte frames */
 754                 addr += 2*75;           /* Lead-in occupies 2 seconds */
 755                 dest[3] = addr % 75;    /* Frames */
 756                 addr /= 75;
 757                 dest[2] = addr % 60;    /* Seconds */
 758                 addr /= 60;
 759                 dest[1] = addr;         /* Minutes */
 760                 dest[0] = 0;            /* Reserved */
 761         } else {
 762                 /* Absolute sector */
 763                 put_unaligned_be32(addr, dest);
 764         }
 765 }
 766
 767
 768 /*-------------------------------------------------------------------------*/
 769
 770
 771 static ssize_t fsg_show_ro(struct device *dev, struct device_attribute *attr,
 772                            char *buf)
 773 {
 774         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 775
 776         return sprintf(buf, "%d\n", fsg_lun_is_open(curlun)
 777                                   ? curlun->ro
 778                                   : curlun->initially_ro);
 779 }
 780
 781 static ssize_t fsg_show_nofua(struct device *dev, struct device_attribute *attr,
 782                               char *buf)
 783 {
 784         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 785
 786         return sprintf(buf, "%u\n", curlun->nofua);
 787 }
 788
 789 static ssize_t fsg_show_file(struct device *dev, struct device_attribute *attr,
 790                              char *buf)
 791 {
 792         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 793         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 794         char            *p;
 795         ssize_t         rc;
 796
 797         down_read(filesem);
 798         if (fsg_lun_is_open(curlun)) {  /* Get the complete pathname */
 799                 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
 800                 if (IS_ERR(p))
 801                         rc = PTR_ERR(p);
 802                 else {
 803                         rc = strlen(p);
 804                         memmove(buf, p, rc);
 805                         buf[rc] = '\n';         /* Add a newline */
 806                         buf[++rc] = 0;
 807                 }
 808         } else {                                /* No file, return 0 bytes */
 809                 *buf = 0;
 810                 rc = 0;
 811         }
 812         up_read(filesem);
 813         return rc;
 814 }
 815
 816
 817 static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr,
 818                             const char *buf, size_t count)
 819 {
 820         ssize_t         rc;
 821         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 822         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 823         unsigned        ro;
 824
 825         rc = kstrtouint(buf, 2, &ro);
 826         if (rc)
 827                 return rc;
 828
 829         /*
 830          * Allow the write-enable status to change only while the
 831          * backing file is closed.
 832          */
 833         down_read(filesem);
 834         if (fsg_lun_is_open(curlun)) {
 835                 LDBG(curlun, "read-only status change prevented\n");
 836                 rc = -EBUSY;
 837         } else {
 838                 curlun->ro = ro;
 839                 curlun->initially_ro = ro;
 840                 LDBG(curlun, "read-only status set to %d\n", curlun->ro);
 841                 rc = count;
 842         }
 843         up_read(filesem);
 844         return rc;
 845 }
 846
 847 static ssize_t fsg_store_nofua(struct device *dev,
 848                                struct device_attribute *attr,
 849                                const char *buf, size_t count)
 850 {
 851         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 852         unsigned        nofua;
 853         int             ret;
 854
 855         ret = kstrtouint(buf, 2, &nofua);
 856         if (ret)
 857                 return ret;
 858
 859         /* Sync data when switching from async mode to sync */
 860         if (!nofua && curlun->nofua)
 861                 fsg_lun_fsync_sub(curlun);
 862
 863         curlun->nofua = nofua;
 864
 865         return count;
 866 }
 867
 868 static ssize_t fsg_store_file(struct device *dev, struct device_attribute *attr,
 869                               const char *buf, size_t count)
 870 {
 871         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 872         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 873         int             rc = 0;
 874
 875         if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) {
 876                 LDBG(curlun, "eject attempt prevented\n");
 877                 return -EBUSY;                          /* "Door is locked" */
 878         }
 879
 880         /* Remove a trailing newline */
 881         if (count > 0 && buf[count-1] == '\n')
 882                 ((char *) buf)[count-1] = 0;            /* Ugh! */
 883
 884         /* Eject current medium */
 885         down_write(filesem);
 886         if (fsg_lun_is_open(curlun)) {
 887                 fsg_lun_close(curlun);
 888                 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
 889         }
 890
 891         /* Load new medium */
 892         if (count > 0 && buf[0]) {
 893                 rc = fsg_lun_open(curlun, buf);
 894                 if (rc == 0)
 895                         curlun->unit_attention_data =
 896                                         SS_NOT_READY_TO_READY_TRANSITION;
 897         }
 898         up_write(filesem);
 899         return (rc < 0 ? rc : count);
 900 }