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 (m.nazarewicz@samsung.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
 151
 152 /*-------------------------------------------------------------------------*/
 153
 154 /* Bulk-only data structures */
 155
 156 /* Command Block Wrapper */
 157 struct fsg_bulk_cb_wrap {
 158         __le32  Signature;              /* Contains 'USBC' */
 159         u32     Tag;                    /* Unique per command id */
 160         __le32  DataTransferLength;     /* Size of the data */
 161         u8      Flags;                  /* Direction in bit 7 */
 162         u8      Lun;                    /* LUN (normally 0) */
 163         u8      Length;                 /* Of the CDB, <= MAX_COMMAND_SIZE */
 164         u8      CDB[16];                /* Command Data Block */
 165 };
 166
 167 #define USB_BULK_CB_WRAP_LEN    31
 168 #define USB_BULK_CB_SIG         0x43425355      /* Spells out USBC */
 169 #define USB_BULK_IN_FLAG        0x80
 170
 171 /* Command Status Wrapper */
 172 struct bulk_cs_wrap {
 173         __le32  Signature;              /* Should = 'USBS' */
 174         u32     Tag;                    /* Same as original command */
 175         __le32  Residue;                /* Amount not transferred */
 176         u8      Status;                 /* See below */
 177 };
 178
 179 #define USB_BULK_CS_WRAP_LEN    13
 180 #define USB_BULK_CS_SIG         0x53425355      /* Spells out 'USBS' */
 181 #define USB_STATUS_PASS         0
 182 #define USB_STATUS_FAIL         1
 183 #define USB_STATUS_PHASE_ERROR  2
 184
 185 /* Bulk-only class specific requests */
 186 #define USB_BULK_RESET_REQUEST          0xff
 187 #define USB_BULK_GET_MAX_LUN_REQUEST    0xfe
 188
 189
 190 /* CBI Interrupt data structure */
 191 struct interrupt_data {
 192         u8      bType;
 193         u8      bValue;
 194 };
 195
 196 #define CBI_INTERRUPT_DATA_LEN          2
 197
 198 /* CBI Accept Device-Specific Command request */
 199 #define USB_CBI_ADSC_REQUEST            0x00
 200
 201
 202 /* Length of a SCSI Command Data Block */
 203 #define MAX_COMMAND_SIZE        16
 204
 205 /* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
 206 #define SS_NO_SENSE                             0
 207 #define SS_COMMUNICATION_FAILURE                0x040800
 208 #define SS_INVALID_COMMAND                      0x052000
 209 #define SS_INVALID_FIELD_IN_CDB                 0x052400
 210 #define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE   0x052100
 211 #define SS_LOGICAL_UNIT_NOT_SUPPORTED           0x052500
 212 #define SS_MEDIUM_NOT_PRESENT                   0x023a00
 213 #define SS_MEDIUM_REMOVAL_PREVENTED             0x055302
 214 #define SS_NOT_READY_TO_READY_TRANSITION        0x062800
 215 #define SS_RESET_OCCURRED                       0x062900
 216 #define SS_SAVING_PARAMETERS_NOT_SUPPORTED      0x053900
 217 #define SS_UNRECOVERED_READ_ERROR               0x031100
 218 #define SS_WRITE_ERROR                          0x030c02
 219 #define SS_WRITE_PROTECTED                      0x072700
 220
 221 #define SK(x)           ((u8) ((x) >> 16))      /* Sense Key byte, etc. */
 222 #define ASC(x)          ((u8) ((x) >> 8))
 223 #define ASCQ(x)         ((u8) (x))
 224
 225
 226 /*-------------------------------------------------------------------------*/
 227
 228
 229 struct fsg_lun {
 230         struct file     *filp;
 231         loff_t          file_length;
 232         loff_t          num_sectors;
 233
 234         unsigned int    initially_ro:1;
 235         unsigned int    ro:1;
 236         unsigned int    removable:1;
 237         unsigned int    cdrom:1;
 238         unsigned int    prevent_medium_removal:1;
 239         unsigned int    registered:1;
 240         unsigned int    info_valid:1;
 241         unsigned int    nofua:1;
 242
 243         u32             sense_data;
 244         u32             sense_data_info;
 245         u32             unit_attention_data;
 246
 247         unsigned int    blkbits;        /* Bits of logical block size of bound block device */
 248         unsigned int    blksize;        /* logical block size of bound block device */
 249         struct device   dev;
 250 };
 251
 252 #define fsg_lun_is_open(curlun) ((curlun)->filp != NULL)
 253
 254 static struct fsg_lun *fsg_lun_from_dev(struct device *dev)
 255 {
 256         return container_of(dev, struct fsg_lun, dev);
 257 }
 258
 259
 260 /* Big enough to hold our biggest descriptor */
 261 #define EP0_BUFSIZE     256
 262 #define DELAYED_STATUS  (EP0_BUFSIZE + 999)     /* An impossibly large value */
 263
 264 #ifdef CONFIG_USB_GADGET_DEBUG_FILES
 265
 266 static unsigned int fsg_num_buffers = CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS;
 267 module_param_named(num_buffers, fsg_num_buffers, uint, S_IRUGO);
 268 MODULE_PARM_DESC(num_buffers, "Number of pipeline buffers");
 269
 270 #else
 271
 272 /*
 273  * Number of buffers we will use.
 274  * 2 is usually enough for good buffering pipeline
 275  */
 276 #define fsg_num_buffers CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS
 277
 278 #endif /* CONFIG_USB_DEBUG */
 279
 280 /* check if fsg_num_buffers is within a valid range */
 281 static inline int fsg_num_buffers_validate(void)
 282 {
 283         if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
 284                 return 0;
 285         pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
 286                fsg_num_buffers, 2 ,4);
 287         return -EINVAL;
 288 }
 289
 290 /* Default size of buffer length. */
 291 #define FSG_BUFLEN      ((u32)16384)
 292
 293 /* Maximal number of LUNs supported in mass storage function */
 294 #define FSG_MAX_LUNS    8
 295
 296 enum fsg_buffer_state {
 297         BUF_STATE_EMPTY = 0,
 298         BUF_STATE_FULL,
 299         BUF_STATE_BUSY
 300 };
 301
 302 struct fsg_buffhd {
 303 #ifdef FSG_BUFFHD_STATIC_BUFFER
 304         char                            buf[FSG_BUFLEN];
 305 #else
 306         void                            *buf;
 307 #endif
 308         enum fsg_buffer_state           state;
 309         struct fsg_buffhd               *next;
 310
 311         /*
 312          * The NetChip 2280 is faster, and handles some protocol faults
 313          * better, if we don't submit any short bulk-out read requests.
 314          * So we will record the intended request length here.
 315          */
 316         unsigned int                    bulk_out_intended_length;
 317
 318         struct usb_request              *inreq;
 319         int                             inreq_busy;
 320         struct usb_request              *outreq;
 321         int                             outreq_busy;
 322 };
 323
 324 enum fsg_state {
 325         /* This one isn't used anywhere */
 326         FSG_STATE_COMMAND_PHASE = -10,
 327         FSG_STATE_DATA_PHASE,
 328         FSG_STATE_STATUS_PHASE,
 329
 330         FSG_STATE_IDLE = 0,
 331         FSG_STATE_ABORT_BULK_OUT,
 332         FSG_STATE_RESET,
 333         FSG_STATE_INTERFACE_CHANGE,
 334         FSG_STATE_CONFIG_CHANGE,
 335         FSG_STATE_DISCONNECT,
 336         FSG_STATE_EXIT,
 337         FSG_STATE_TERMINATED
 338 };
 339
 340 enum data_direction {
 341         DATA_DIR_UNKNOWN = 0,
 342         DATA_DIR_FROM_HOST,
 343         DATA_DIR_TO_HOST,
 344         DATA_DIR_NONE
 345 };
 346
 347
 348 /*-------------------------------------------------------------------------*/
 349
 350
 351 static inline u32 get_unaligned_be24(u8 *buf)
 352 {
 353         return 0xffffff & (u32) get_unaligned_be32(buf - 1);
 354 }
 355
 356
 357 /*-------------------------------------------------------------------------*/
 358
 359
 360 enum {
 361 #ifndef FSG_NO_DEVICE_STRINGS
 362         FSG_STRING_MANUFACTURER = 1,
 363         FSG_STRING_PRODUCT,
 364         FSG_STRING_SERIAL,
 365         FSG_STRING_CONFIG,
 366 #endif
 367         FSG_STRING_INTERFACE
 368 };
 369
 370
 371 #ifndef FSG_NO_OTG
 372 static struct usb_otg_descriptor
 373 fsg_otg_desc = {
 374         .bLength =              sizeof fsg_otg_desc,
 375         .bDescriptorType =      USB_DT_OTG,
 376
 377         .bmAttributes =         USB_OTG_SRP,
 378 };
 379 #endif
 380
 381 /* There is only one interface. */
 382
 383 static struct usb_interface_descriptor
 384 fsg_intf_desc = {
 385         .bLength =              sizeof fsg_intf_desc,
 386         .bDescriptorType =      USB_DT_INTERFACE,
 387
 388         .bNumEndpoints =        2,              /* Adjusted during fsg_bind() */
 389         .bInterfaceClass =      USB_CLASS_MASS_STORAGE,
 390         .bInterfaceSubClass =   USB_SC_SCSI,    /* Adjusted during fsg_bind() */
 391         .bInterfaceProtocol =   USB_PR_BULK,    /* Adjusted during fsg_bind() */
 392         .iInterface =           FSG_STRING_INTERFACE,
 393 };
 394
 395 /*
 396  * Three full-speed endpoint descriptors: bulk-in, bulk-out, and
 397  * interrupt-in.
 398  */
 399
 400 static struct usb_endpoint_descriptor
 401 fsg_fs_bulk_in_desc = {
 402         .bLength =              USB_DT_ENDPOINT_SIZE,
 403         .bDescriptorType =      USB_DT_ENDPOINT,
 404
 405         .bEndpointAddress =     USB_DIR_IN,
 406         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 407         /* wMaxPacketSize set by autoconfiguration */
 408 };
 409
 410 static struct usb_endpoint_descriptor
 411 fsg_fs_bulk_out_desc = {
 412         .bLength =              USB_DT_ENDPOINT_SIZE,
 413         .bDescriptorType =      USB_DT_ENDPOINT,
 414
 415         .bEndpointAddress =     USB_DIR_OUT,
 416         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 417         /* wMaxPacketSize set by autoconfiguration */
 418 };
 419
 420 #ifndef FSG_NO_INTR_EP
 421
 422 static struct usb_endpoint_descriptor
 423 fsg_fs_intr_in_desc = {
 424         .bLength =              USB_DT_ENDPOINT_SIZE,
 425         .bDescriptorType =      USB_DT_ENDPOINT,
 426
 427         .bEndpointAddress =     USB_DIR_IN,
 428         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 429         .wMaxPacketSize =       cpu_to_le16(2),
 430         .bInterval =            32,     /* frames -> 32 ms */
 431 };
 432
 433 #ifndef FSG_NO_OTG
 434 #  define FSG_FS_FUNCTION_PRE_EP_ENTRIES        2
 435 #else
 436 #  define FSG_FS_FUNCTION_PRE_EP_ENTRIES        1
 437 #endif
 438
 439 #endif
 440
 441 static struct usb_descriptor_header *fsg_fs_function[] = {
 442 #ifndef FSG_NO_OTG
 443         (struct usb_descriptor_header *) &fsg_otg_desc,
 444 #endif
 445         (struct usb_descriptor_header *) &fsg_intf_desc,
 446         (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc,
 447         (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc,
 448 #ifndef FSG_NO_INTR_EP
 449         (struct usb_descriptor_header *) &fsg_fs_intr_in_desc,
 450 #endif
 451         NULL,
 452 };
 453
 454
 455 /*
 456  * USB 2.0 devices need to expose both high speed and full speed
 457  * descriptors, unless they only run at full speed.
 458  *
 459  * That means alternate endpoint descriptors (bigger packets)
 460  * and a "device qualifier" ... plus more construction options
 461  * for the configuration descriptor.
 462  */
 463 static struct usb_endpoint_descriptor
 464 fsg_hs_bulk_in_desc = {
 465         .bLength =              USB_DT_ENDPOINT_SIZE,
 466         .bDescriptorType =      USB_DT_ENDPOINT,
 467
 468         /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
 469         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 470         .wMaxPacketSize =       cpu_to_le16(512),
 471 };
 472
 473 static struct usb_endpoint_descriptor
 474 fsg_hs_bulk_out_desc = {
 475         .bLength =              USB_DT_ENDPOINT_SIZE,
 476         .bDescriptorType =      USB_DT_ENDPOINT,
 477
 478         /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
 479         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 480         .wMaxPacketSize =       cpu_to_le16(512),
 481         .bInterval =            1,      /* NAK every 1 uframe */
 482 };
 483
 484 #ifndef FSG_NO_INTR_EP
 485
 486 static struct usb_endpoint_descriptor
 487 fsg_hs_intr_in_desc = {
 488         .bLength =              USB_DT_ENDPOINT_SIZE,
 489         .bDescriptorType =      USB_DT_ENDPOINT,
 490
 491         /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
 492         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 493         .wMaxPacketSize =       cpu_to_le16(2),
 494         .bInterval =            9,      /* 2**(9-1) = 256 uframes -> 32 ms */
 495 };
 496
 497 #ifndef FSG_NO_OTG
 498 #  define FSG_HS_FUNCTION_PRE_EP_ENTRIES        2
 499 #else
 500 #  define FSG_HS_FUNCTION_PRE_EP_ENTRIES        1
 501 #endif
 502
 503 #endif
 504
 505 static struct usb_descriptor_header *fsg_hs_function[] = {
 506 #ifndef FSG_NO_OTG
 507         (struct usb_descriptor_header *) &fsg_otg_desc,
 508 #endif
 509         (struct usb_descriptor_header *) &fsg_intf_desc,
 510         (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc,
 511         (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc,
 512 #ifndef FSG_NO_INTR_EP
 513         (struct usb_descriptor_header *) &fsg_hs_intr_in_desc,
 514 #endif
 515         NULL,
 516 };
 517
 518 static struct usb_endpoint_descriptor
 519 fsg_ss_bulk_in_desc = {
 520         .bLength =              USB_DT_ENDPOINT_SIZE,
 521         .bDescriptorType =      USB_DT_ENDPOINT,
 522
 523         /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
 524         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 525         .wMaxPacketSize =       cpu_to_le16(1024),
 526 };
 527
 528 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc = {
 529         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 530         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 531
 532         /*.bMaxBurst =          DYNAMIC, */
 533 };
 534
 535 static struct usb_endpoint_descriptor
 536 fsg_ss_bulk_out_desc = {
 537         .bLength =              USB_DT_ENDPOINT_SIZE,
 538         .bDescriptorType =      USB_DT_ENDPOINT,
 539
 540         /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
 541         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 542         .wMaxPacketSize =       cpu_to_le16(1024),
 543 };
 544
 545 static struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc = {
 546         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 547         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 548
 549         /*.bMaxBurst =          DYNAMIC, */
 550 };
 551
 552 #ifndef FSG_NO_INTR_EP
 553
 554 static struct usb_endpoint_descriptor
 555 fsg_ss_intr_in_desc = {
 556         .bLength =              USB_DT_ENDPOINT_SIZE,
 557         .bDescriptorType =      USB_DT_ENDPOINT,
 558
 559         /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
 560         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 561         .wMaxPacketSize =       cpu_to_le16(2),
 562         .bInterval =            9,      /* 2**(9-1) = 256 uframes -> 32 ms */
 563 };
 564
 565 static struct usb_ss_ep_comp_descriptor fsg_ss_intr_in_comp_desc = {
 566         .bLength =              sizeof(fsg_ss_bulk_in_comp_desc),
 567         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 568
 569         .wBytesPerInterval =    cpu_to_le16(2),
 570 };
 571
 572 #ifndef FSG_NO_OTG
 573 #  define FSG_SS_FUNCTION_PRE_EP_ENTRIES        2
 574 #else
 575 #  define FSG_SS_FUNCTION_PRE_EP_ENTRIES        1
 576 #endif
 577
 578 #endif
 579
 580 static __maybe_unused struct usb_ext_cap_descriptor fsg_ext_cap_desc = {
 581         .bLength =              USB_DT_USB_EXT_CAP_SIZE,
 582         .bDescriptorType =      USB_DT_DEVICE_CAPABILITY,
 583         .bDevCapabilityType =   USB_CAP_TYPE_EXT,
 584
 585         .bmAttributes =         cpu_to_le32(USB_LPM_SUPPORT),
 586 };
 587
 588 static __maybe_unused struct usb_ss_cap_descriptor fsg_ss_cap_desc = {
 589         .bLength =              USB_DT_USB_SS_CAP_SIZE,
 590         .bDescriptorType =      USB_DT_DEVICE_CAPABILITY,
 591         .bDevCapabilityType =   USB_SS_CAP_TYPE,
 592
 593         /* .bmAttributes = LTM is not supported yet */
 594
 595         .wSpeedSupported =      cpu_to_le16(USB_LOW_SPEED_OPERATION
 596                 | USB_FULL_SPEED_OPERATION
 597                 | USB_HIGH_SPEED_OPERATION
 598                 | USB_5GBPS_OPERATION),
 599         .bFunctionalitySupport = USB_LOW_SPEED_OPERATION,
 600         .bU1devExitLat =        USB_DEFAULT_U1_DEV_EXIT_LAT,
 601         .bU2DevExitLat =        cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT),
 602 };
 603
 604 static __maybe_unused struct usb_bos_descriptor fsg_bos_desc = {
 605         .bLength =              USB_DT_BOS_SIZE,
 606         .bDescriptorType =      USB_DT_BOS,
 607
 608         .wTotalLength =         cpu_to_le16(USB_DT_BOS_SIZE
 609                                 + USB_DT_USB_EXT_CAP_SIZE
 610                                 + USB_DT_USB_SS_CAP_SIZE),
 611
 612         .bNumDeviceCaps =       2,
 613 };
 614
 615 static struct usb_descriptor_header *fsg_ss_function[] = {
 616 #ifndef FSG_NO_OTG
 617         (struct usb_descriptor_header *) &fsg_otg_desc,
 618 #endif
 619         (struct usb_descriptor_header *) &fsg_intf_desc,
 620         (struct usb_descriptor_header *) &fsg_ss_bulk_in_desc,
 621         (struct usb_descriptor_header *) &fsg_ss_bulk_in_comp_desc,
 622         (struct usb_descriptor_header *) &fsg_ss_bulk_out_desc,
 623         (struct usb_descriptor_header *) &fsg_ss_bulk_out_comp_desc,
 624 #ifndef FSG_NO_INTR_EP
 625         (struct usb_descriptor_header *) &fsg_ss_intr_in_desc,
 626         (struct usb_descriptor_header *) &fsg_ss_intr_in_comp_desc,
 627 #endif
 628         NULL,
 629 };
 630
 631 /* Maxpacket and other transfer characteristics vary by speed. */
 632 static __maybe_unused struct usb_endpoint_descriptor *
 633 fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
 634                 struct usb_endpoint_descriptor *hs,
 635                 struct usb_endpoint_descriptor *ss)
 636 {
 637         if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
 638                 return ss;
 639         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 640                 return hs;
 641         return fs;
 642 }
 643
 644
 645 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
 646 static struct usb_string                fsg_strings[] = {
 647 #ifndef FSG_NO_DEVICE_STRINGS
 648         {FSG_STRING_MANUFACTURER,       fsg_string_manufacturer},
 649         {FSG_STRING_PRODUCT,            fsg_string_product},
 650         {FSG_STRING_SERIAL,             ""},
 651         {FSG_STRING_CONFIG,             fsg_string_config},
 652 #endif
 653         {FSG_STRING_INTERFACE,          fsg_string_interface},
 654         {}
 655 };
 656
 657 static struct usb_gadget_strings        fsg_stringtab = {
 658         .language       = 0x0409,               /* en-us */
 659         .strings        = fsg_strings,
 660 };
 661
 662
 663  /*-------------------------------------------------------------------------*/
 664
 665 /*
 666  * If the next two routines are called while the gadget is registered,
 667  * the caller must own fsg->filesem for writing.
 668  */
 669
 670 static int fsg_lun_open(struct fsg_lun *curlun, const char *filename)
 671 {
 672         int                             ro;
 673         struct file                     *filp = NULL;
 674         int                             rc = -EINVAL;
 675         struct inode                    *inode = NULL;
 676         loff_t                          size;
 677         loff_t                          num_sectors;
 678         loff_t                          min_sectors;
 679
 680         /* R/W if we can, R/O if we must */
 681         ro = curlun->initially_ro;
 682         if (!ro) {
 683                 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
 684                 if (PTR_ERR(filp) == -EROFS || PTR_ERR(filp) == -EACCES)
 685                         ro = 1;
 686         }
 687         if (ro)
 688                 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
 689         if (IS_ERR(filp)) {
 690                 LINFO(curlun, "unable to open backing file: %s\n", filename);
 691                 return PTR_ERR(filp);
 692         }
 693
 694         if (!(filp->f_mode & FMODE_WRITE))
 695                 ro = 1;
 696
 697         if (filp->f_path.dentry)
 698                 inode = filp->f_path.dentry->d_inode;
 699         if (!inode || (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))) {
 700                 LINFO(curlun, "invalid file type: %s\n", filename);
 701                 goto out;
 702         }
 703
 704         /*
 705          * If we can't read the file, it's no good.
 706          * If we can't write the file, use it read-only.
 707          */
 708         if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
 709                 LINFO(curlun, "file not readable: %s\n", filename);
 710                 goto out;
 711         }
 712         if (!(filp->f_op->write || filp->f_op->aio_write))
 713                 ro = 1;
 714
 715         size = i_size_read(inode->i_mapping->host);
 716         if (size < 0) {
 717                 LINFO(curlun, "unable to find file size: %s\n", filename);
 718                 rc = (int) size;
 719                 goto out;
 720         }
 721
 722         if (curlun->cdrom) {
 723                 curlun->blksize = 2048;
 724                 curlun->blkbits = 11;
 725         } else if (inode->i_bdev) {
 726                 curlun->blksize = bdev_logical_block_size(inode->i_bdev);
 727                 curlun->blkbits = blksize_bits(curlun->blksize);
 728         } else {
 729                 curlun->blksize = 512;
 730                 curlun->blkbits = 9;
 731         }
 732
 733         num_sectors = size >> curlun->blkbits; /* File size in logic-block-size blocks */
 734         min_sectors = 1;
 735         if (curlun->cdrom) {
 736                 min_sectors = 300;      /* Smallest track is 300 frames */
 737                 if (num_sectors >= 256*60*75) {
 738                         num_sectors = 256*60*75 - 1;
 739                         LINFO(curlun, "file too big: %s\n", filename);
 740                         LINFO(curlun, "using only first %d blocks\n",
 741                                         (int) num_sectors);
 742                 }
 743         }
 744         if (num_sectors < min_sectors) {
 745                 LINFO(curlun, "file too small: %s\n", filename);
 746                 rc = -ETOOSMALL;
 747                 goto out;
 748         }
 749
 750         get_file(filp);
 751         curlun->ro = ro;
 752         curlun->filp = filp;
 753         curlun->file_length = size;
 754         curlun->num_sectors = num_sectors;
 755         LDBG(curlun, "open backing file: %s\n", filename);
 756         rc = 0;
 757
 758 out:
 759         filp_close(filp, current->files);
 760         return rc;
 761 }
 762
 763
 764 static void fsg_lun_close(struct fsg_lun *curlun)
 765 {
 766         if (curlun->filp) {
 767                 LDBG(curlun, "close backing file\n");
 768                 fput(curlun->filp);
 769                 curlun->filp = NULL;
 770         }
 771 }
 772
 773
 774 /*-------------------------------------------------------------------------*/
 775
 776 /*
 777  * Sync the file data, don't bother with the metadata.
 778  * This code was copied from fs/buffer.c:sys_fdatasync().
 779  */
 780 static int fsg_lun_fsync_sub(struct fsg_lun *curlun)
 781 {
 782         struct file     *filp = curlun->filp;
 783
 784         if (curlun->ro || !filp)
 785                 return 0;
 786         return vfs_fsync(filp, 1);
 787 }
 788
 789 static void store_cdrom_address(u8 *dest, int msf, u32 addr)
 790 {
 791         if (msf) {
 792                 /* Convert to Minutes-Seconds-Frames */
 793                 addr >>= 2;             /* Convert to 2048-byte frames */
 794                 addr += 2*75;           /* Lead-in occupies 2 seconds */
 795                 dest[3] = addr % 75;    /* Frames */
 796                 addr /= 75;
 797                 dest[2] = addr % 60;    /* Seconds */
 798                 addr /= 60;
 799                 dest[1] = addr;         /* Minutes */
 800                 dest[0] = 0;            /* Reserved */
 801         } else {
 802                 /* Absolute sector */
 803                 put_unaligned_be32(addr, dest);
 804         }
 805 }
 806
 807
 808 /*-------------------------------------------------------------------------*/
 809
 810
 811 static ssize_t fsg_show_ro(struct device *dev, struct device_attribute *attr,
 812                            char *buf)
 813 {
 814         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 815
 816         return sprintf(buf, "%d\n", fsg_lun_is_open(curlun)
 817                                   ? curlun->ro
 818                                   : curlun->initially_ro);
 819 }
 820
 821 static ssize_t fsg_show_nofua(struct device *dev, struct device_attribute *attr,
 822                               char *buf)
 823 {
 824         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 825
 826         return sprintf(buf, "%u\n", curlun->nofua);
 827 }
 828
 829 static ssize_t fsg_show_file(struct device *dev, struct device_attribute *attr,
 830                              char *buf)
 831 {
 832         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 833         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 834         char            *p;
 835         ssize_t         rc;
 836
 837         down_read(filesem);
 838         if (fsg_lun_is_open(curlun)) {  /* Get the complete pathname */
 839                 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1);
 840                 if (IS_ERR(p))
 841                         rc = PTR_ERR(p);
 842                 else {
 843                         rc = strlen(p);
 844                         memmove(buf, p, rc);
 845                         buf[rc] = '\n';         /* Add a newline */
 846                         buf[++rc] = 0;
 847                 }
 848         } else {                                /* No file, return 0 bytes */
 849                 *buf = 0;
 850                 rc = 0;
 851         }
 852         up_read(filesem);
 853         return rc;
 854 }
 855
 856
 857 static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr,
 858                             const char *buf, size_t count)
 859 {
 860         ssize_t         rc;
 861         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 862         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 863         unsigned        ro;
 864
 865         rc = kstrtouint(buf, 2, &ro);
 866         if (rc)
 867                 return rc;
 868
 869         /*
 870          * Allow the write-enable status to change only while the
 871          * backing file is closed.
 872          */
 873         down_read(filesem);
 874         if (fsg_lun_is_open(curlun)) {
 875                 LDBG(curlun, "read-only status change prevented\n");
 876                 rc = -EBUSY;
 877         } else {
 878                 curlun->ro = ro;
 879                 curlun->initially_ro = ro;
 880                 LDBG(curlun, "read-only status set to %d\n", curlun->ro);
 881                 rc = count;
 882         }
 883         up_read(filesem);
 884         return rc;
 885 }
 886
 887 static ssize_t fsg_store_nofua(struct device *dev,
 888                                struct device_attribute *attr,
 889                                const char *buf, size_t count)
 890 {
 891         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 892         unsigned        nofua;
 893         int             ret;
 894
 895         ret = kstrtouint(buf, 2, &nofua);
 896         if (ret)
 897                 return ret;
 898
 899         /* Sync data when switching from async mode to sync */
 900         if (!nofua && curlun->nofua)
 901                 fsg_lun_fsync_sub(curlun);
 902
 903         curlun->nofua = nofua;
 904
 905         return count;
 906 }
 907
 908 static ssize_t fsg_store_file(struct device *dev, struct device_attribute *attr,
 909                               const char *buf, size_t count)
 910 {
 911         struct fsg_lun  *curlun = fsg_lun_from_dev(dev);
 912         struct rw_semaphore     *filesem = dev_get_drvdata(dev);
 913         int             rc = 0;
 914
 915         if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) {
 916                 LDBG(curlun, "eject attempt prevented\n");
 917                 return -EBUSY;                          /* "Door is locked" */
 918         }
 919
 920         /* Remove a trailing newline */
 921         if (count > 0 && buf[count-1] == '\n')
 922                 ((char *) buf)[count-1] = 0;            /* Ugh! */
 923
 924         /* Eject current medium */
 925         down_write(filesem);
 926         if (fsg_lun_is_open(curlun)) {
 927                 fsg_lun_close(curlun);
 928                 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
 929         }
 930
 931         /* Load new medium */
 932         if (count > 0 && buf[0]) {
 933                 rc = fsg_lun_open(curlun, buf);
 934                 if (rc == 0)
 935                         curlun->unit_attention_data =
 936                                         SS_NOT_READY_TO_READY_TRANSITION;
 937         }
 938         up_write(filesem);
 939         return (rc < 0 ? rc : count);
 940 }