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 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 24/* 25 * This file requires the following identifiers used in USB strings to 26 * be defined (each of type pointer to char): 27 * - fsg_string_manufacturer -- name of the manufacturer 28 * - fsg_string_product -- name of the product 29 * - fsg_string_serial -- product's serial 30 * - fsg_string_config -- name of the configuration 31 * - fsg_string_interface -- name of the interface 32 * The first four are only needed when FSG_DESCRIPTORS_DEVICE_STRINGS 33 * macro is defined prior to including this file. 34 */ 35 36/* 37 * When FSG_NO_INTR_EP is defined fsg_fs_intr_in_desc and 38 * fsg_hs_intr_in_desc objects as well as 39 * FSG_FS_FUNCTION_PRE_EP_ENTRIES and FSG_HS_FUNCTION_PRE_EP_ENTRIES 40 * macros are not defined. 41 * 42 * When FSG_NO_DEVICE_STRINGS is defined FSG_STRING_MANUFACTURER, 43 * FSG_STRING_PRODUCT, FSG_STRING_SERIAL and FSG_STRING_CONFIG are not 44 * defined (as well as corresponding entries in string tables are 45 * missing) and FSG_STRING_INTERFACE has value of zero. 46 * 47 * When FSG_NO_OTG is defined fsg_otg_desc won't be defined. 48 */ 49 50/* 51 * When FSG_BUFFHD_STATIC_BUFFER is defined when this file is included 52 * the fsg_buffhd structure's buf field will be an array of FSG_BUFLEN 53 * characters rather then a pointer to void. 54 */ 55 56 57#include <asm/unaligned.h> 58 59 60/* 61 * Thanks to NetChip Technologies for donating this product ID. 62 * 63 * DO NOT REUSE THESE IDs with any other driver!! Ever!! 64 * Instead: allocate your own, using normal USB-IF procedures. 65 */ 66#define FSG_VENDOR_ID 0x0525 /* NetChip */ 67#define FSG_PRODUCT_ID 0xa4a5 /* Linux-USB File-backed Storage Gadget */ 68 69 70/*-------------------------------------------------------------------------*/ 71 72 73#ifndef DEBUG 74#undef VERBOSE_DEBUG 75#undef DUMP_MSGS 76#endif /* !DEBUG */ 77 78#ifdef VERBOSE_DEBUG 79#define VLDBG LDBG 80#else 81#define VLDBG(lun, fmt, args...) do { } while (0) 82#endif /* VERBOSE_DEBUG */ 83 84#define LDBG(lun, fmt, args...) dev_dbg (&(lun)->dev, fmt, ## args) 85#define LERROR(lun, fmt, args...) dev_err (&(lun)->dev, fmt, ## args) 86#define LWARN(lun, fmt, args...) dev_warn(&(lun)->dev, fmt, ## args) 87#define LINFO(lun, fmt, args...) dev_info(&(lun)->dev, fmt, ## args) 88 89/* 90 * Keep those macros in sync with those in 91 * include/linux/usb/composite.h or else GCC will complain. If they 92 * are identical (the same names of arguments, white spaces in the 93 * same places) GCC will allow redefinition otherwise (even if some 94 * white space is removed or added) warning will be issued. 95 * 96 * Those macros are needed here because File Storage Gadget does not 97 * include the composite.h header. For composite gadgets those macros 98 * are redundant since composite.h is included any way. 99 * 100 * One could check whether those macros are already defined (which 101 * would indicate composite.h had been included) or not (which would 102 * indicate we were in FSG) but this is not done because a warning is 103 * desired if definitions here differ from the ones in composite.h. 104 * 105 * We want the definitions to match and be the same in File Storage 106 * Gadget as well as Mass Storage Function (and so composite gadgets 107 * using MSF). If someone changes them in composite.h it will produce 108 * a warning in this file when building MSF. 109 */ 110#define DBG(d, fmt, args...) dev_dbg(&(d)->gadget->dev , fmt , ## args) 111#define VDBG(d, fmt, args...) dev_vdbg(&(d)->gadget->dev , fmt , ## args) 112#define ERROR(d, fmt, args...) dev_err(&(d)->gadget->dev , fmt , ## args) 113#define WARNING(d, fmt, args...) dev_warn(&(d)->gadget->dev , fmt , ## args) 114#define INFO(d, fmt, args...) dev_info(&(d)->gadget->dev , fmt , ## args) 115 116 117 118#ifdef DUMP_MSGS 119 120# define dump_msg(fsg, /* const char * */ label, \ 121 /* const u8 * */ buf, /* unsigned */ length) do { \ 122 if (length < 512) { \ 123 DBG(fsg, "%s, length %u:\n", label, length); \ 124 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, \ 125 16, 1, buf, length, 0); \ 126 } \ 127} while (0) 128 129# define dump_cdb(fsg) do { } while (0) 130 131#else 132 133# define dump_msg(fsg, /* const char * */ label, \ 134 /* const u8 * */ buf, /* unsigned */ length) do { } while (0) 135 136# ifdef VERBOSE_DEBUG 137 138# define dump_cdb(fsg) \ 139 print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE, \ 140 16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0) \ 141 142# else 143 144# define dump_cdb(fsg) do { } while (0) 145 146# endif /* VERBOSE_DEBUG */ 147 148#endif /* DUMP_MSGS */ 149 150 151 152 153 154/*-------------------------------------------------------------------------*/ 155 156/* SCSI device types */ 157#define TYPE_DISK 0x00 158#define TYPE_CDROM 0x05 159 160/* USB protocol value = the transport method */ 161#define USB_PR_CBI 0x00 /* Control/Bulk/Interrupt */ 162#define USB_PR_CB 0x01 /* Control/Bulk w/o interrupt */ 163#define USB_PR_BULK 0x50 /* Bulk-only */ 164 165/* USB subclass value = the protocol encapsulation */ 166#define USB_SC_RBC 0x01 /* Reduced Block Commands (flash) */ 167#define USB_SC_8020 0x02 /* SFF-8020i, MMC-2, ATAPI (CD-ROM) */ 168#define USB_SC_QIC 0x03 /* QIC-157 (tape) */ 169#define USB_SC_UFI 0x04 /* UFI (floppy) */ 170#define USB_SC_8070 0x05 /* SFF-8070i (removable) */ 171#define USB_SC_SCSI 0x06 /* Transparent SCSI */ 172 173/* Bulk-only data structures */ 174 175/* Command Block Wrapper */ 176struct fsg_bulk_cb_wrap { 177 __le32 Signature; /* Contains 'USBC' */ 178 u32 Tag; /* Unique per command id */ 179 __le32 DataTransferLength; /* Size of the data */ 180 u8 Flags; /* Direction in bit 7 */ 181 u8 Lun; /* LUN (normally 0) */ 182 u8 Length; /* Of the CDB, <= MAX_COMMAND_SIZE */ 183 u8 CDB[16]; /* Command Data Block */ 184}; 185 186#define USB_BULK_CB_WRAP_LEN 31 187#define USB_BULK_CB_SIG 0x43425355 /* Spells out USBC */ 188#define USB_BULK_IN_FLAG 0x80 189 190/* Command Status Wrapper */ 191struct bulk_cs_wrap { 192 __le32 Signature; /* Should = 'USBS' */ 193 u32 Tag; /* Same as original command */ 194 __le32 Residue; /* Amount not transferred */ 195 u8 Status; /* See below */ 196}; 197 198#define USB_BULK_CS_WRAP_LEN 13 199#define USB_BULK_CS_SIG 0x53425355 /* Spells out 'USBS' */ 200#define USB_STATUS_PASS 0 201#define USB_STATUS_FAIL 1 202#define USB_STATUS_PHASE_ERROR 2 203 204/* Bulk-only class specific requests */ 205#define USB_BULK_RESET_REQUEST 0xff 206#define USB_BULK_GET_MAX_LUN_REQUEST 0xfe 207 208 209/* CBI Interrupt data structure */ 210struct interrupt_data { 211 u8 bType; 212 u8 bValue; 213}; 214 215#define CBI_INTERRUPT_DATA_LEN 2 216 217/* CBI Accept Device-Specific Command request */ 218#define USB_CBI_ADSC_REQUEST 0x00 219 220 221/* Length of a SCSI Command Data Block */ 222#define MAX_COMMAND_SIZE 16 223 224/* SCSI commands that we recognize */ 225#define SC_FORMAT_UNIT 0x04 226#define SC_INQUIRY 0x12 227#define SC_MODE_SELECT_6 0x15 228#define SC_MODE_SELECT_10 0x55 229#define SC_MODE_SENSE_6 0x1a 230#define SC_MODE_SENSE_10 0x5a 231#define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e 232#define SC_READ_6 0x08 233#define SC_READ_10 0x28 234#define SC_READ_12 0xa8 235#define SC_READ_CAPACITY 0x25 236#define SC_READ_FORMAT_CAPACITIES 0x23 237#define SC_READ_HEADER 0x44 238#define SC_READ_TOC 0x43 239#define SC_RELEASE 0x17 240#define SC_REQUEST_SENSE 0x03 241#define SC_RESERVE 0x16 242#define SC_SEND_DIAGNOSTIC 0x1d 243#define SC_START_STOP_UNIT 0x1b 244#define SC_SYNCHRONIZE_CACHE 0x35 245#define SC_TEST_UNIT_READY 0x00 246#define SC_VERIFY 0x2f 247#define SC_WRITE_6 0x0a 248#define SC_WRITE_10 0x2a 249#define SC_WRITE_12 0xaa 250 251/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */ 252#define SS_NO_SENSE 0 253#define SS_COMMUNICATION_FAILURE 0x040800 254#define SS_INVALID_COMMAND 0x052000 255#define SS_INVALID_FIELD_IN_CDB 0x052400 256#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100 257#define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500 258#define SS_MEDIUM_NOT_PRESENT 0x023a00 259#define SS_MEDIUM_REMOVAL_PREVENTED 0x055302 260#define SS_NOT_READY_TO_READY_TRANSITION 0x062800 261#define SS_RESET_OCCURRED 0x062900 262#define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900 263#define SS_UNRECOVERED_READ_ERROR 0x031100 264#define SS_WRITE_ERROR 0x030c02 265#define SS_WRITE_PROTECTED 0x072700 266 267#define SK(x) ((u8) ((x) >> 16)) /* Sense Key byte, etc. */ 268#define ASC(x) ((u8) ((x) >> 8)) 269#define ASCQ(x) ((u8) (x)) 270 271 272/*-------------------------------------------------------------------------*/ 273 274 275struct fsg_lun { 276 struct file *filp; 277 loff_t file_length; 278 loff_t num_sectors; 279 280 unsigned int initially_ro:1; 281 unsigned int ro:1; 282 unsigned int removable:1; 283 unsigned int cdrom:1; 284 unsigned int prevent_medium_removal:1; 285 unsigned int registered:1; 286 unsigned int info_valid:1; 287 unsigned int nofua:1; 288 289 u32 sense_data; 290 u32 sense_data_info; 291 u32 unit_attention_data; 292 293 struct device dev; 294}; 295 296#define fsg_lun_is_open(curlun) ((curlun)->filp != NULL) 297 298static struct fsg_lun *fsg_lun_from_dev(struct device *dev) 299{ 300 return container_of(dev, struct fsg_lun, dev); 301} 302 303 304/* Big enough to hold our biggest descriptor */ 305#define EP0_BUFSIZE 256 306#define DELAYED_STATUS (EP0_BUFSIZE + 999) /* An impossibly large value */ 307 308/* Number of buffers we will use. 2 is enough for double-buffering */ 309#define FSG_NUM_BUFFERS 2 310 311/* Default size of buffer length. */ 312#define FSG_BUFLEN ((u32)16384) 313 314/* Maximal number of LUNs supported in mass storage function */ 315#define FSG_MAX_LUNS 8 316 317enum fsg_buffer_state { 318 BUF_STATE_EMPTY = 0, 319 BUF_STATE_FULL, 320 BUF_STATE_BUSY 321}; 322 323struct fsg_buffhd { 324#ifdef FSG_BUFFHD_STATIC_BUFFER 325 char buf[FSG_BUFLEN]; 326#else 327 void *buf; 328#endif 329 enum fsg_buffer_state state; 330 struct fsg_buffhd *next; 331 332 /* 333 * The NetChip 2280 is faster, and handles some protocol faults 334 * better, if we don't submit any short bulk-out read requests. 335 * So we will record the intended request length here. 336 */ 337 unsigned int bulk_out_intended_length; 338 339 struct usb_request *inreq; 340 int inreq_busy; 341 struct usb_request *outreq; 342 int outreq_busy; 343}; 344 345enum fsg_state { 346 /* This one isn't used anywhere */ 347 FSG_STATE_COMMAND_PHASE = -10, 348 FSG_STATE_DATA_PHASE, 349 FSG_STATE_STATUS_PHASE, 350 351 FSG_STATE_IDLE = 0, 352 FSG_STATE_ABORT_BULK_OUT, 353 FSG_STATE_RESET, 354 FSG_STATE_INTERFACE_CHANGE, 355 FSG_STATE_CONFIG_CHANGE, 356 FSG_STATE_DISCONNECT, 357 FSG_STATE_EXIT, 358 FSG_STATE_TERMINATED 359}; 360 361enum data_direction { 362 DATA_DIR_UNKNOWN = 0, 363 DATA_DIR_FROM_HOST, 364 DATA_DIR_TO_HOST, 365 DATA_DIR_NONE 366}; 367 368 369/*-------------------------------------------------------------------------*/ 370 371 372static inline u32 get_unaligned_be24(u8 *buf) 373{ 374 return 0xffffff & (u32) get_unaligned_be32(buf - 1); 375} 376 377 378/*-------------------------------------------------------------------------*/ 379 380 381enum { 382#ifndef FSG_NO_DEVICE_STRINGS 383 FSG_STRING_MANUFACTURER = 1, 384 FSG_STRING_PRODUCT, 385 FSG_STRING_SERIAL, 386 FSG_STRING_CONFIG, 387#endif 388 FSG_STRING_INTERFACE 389}; 390 391 392#ifndef FSG_NO_OTG 393static struct usb_otg_descriptor 394fsg_otg_desc = { 395 .bLength = sizeof fsg_otg_desc, 396 .bDescriptorType = USB_DT_OTG, 397 398 .bmAttributes = USB_OTG_SRP, 399}; 400#endif 401 402/* There is only one interface. */ 403 404static struct usb_interface_descriptor 405fsg_intf_desc = { 406 .bLength = sizeof fsg_intf_desc, 407 .bDescriptorType = USB_DT_INTERFACE, 408 409 .bNumEndpoints = 2, /* Adjusted during fsg_bind() */ 410 .bInterfaceClass = USB_CLASS_MASS_STORAGE, 411 .bInterfaceSubClass = USB_SC_SCSI, /* Adjusted during fsg_bind() */ 412 .bInterfaceProtocol = USB_PR_BULK, /* Adjusted during fsg_bind() */ 413 .iInterface = FSG_STRING_INTERFACE, 414}; 415 416/* 417 * Three full-speed endpoint descriptors: bulk-in, bulk-out, and 418 * interrupt-in. 419 */ 420 421static struct usb_endpoint_descriptor 422fsg_fs_bulk_in_desc = { 423 .bLength = USB_DT_ENDPOINT_SIZE, 424 .bDescriptorType = USB_DT_ENDPOINT, 425 426 .bEndpointAddress = USB_DIR_IN, 427 .bmAttributes = USB_ENDPOINT_XFER_BULK, 428 /* wMaxPacketSize set by autoconfiguration */ 429}; 430 431static struct usb_endpoint_descriptor 432fsg_fs_bulk_out_desc = { 433 .bLength = USB_DT_ENDPOINT_SIZE, 434 .bDescriptorType = USB_DT_ENDPOINT, 435 436 .bEndpointAddress = USB_DIR_OUT, 437 .bmAttributes = USB_ENDPOINT_XFER_BULK, 438 /* wMaxPacketSize set by autoconfiguration */ 439}; 440 441#ifndef FSG_NO_INTR_EP 442 443static struct usb_endpoint_descriptor 444fsg_fs_intr_in_desc = { 445 .bLength = USB_DT_ENDPOINT_SIZE, 446 .bDescriptorType = USB_DT_ENDPOINT, 447 448 .bEndpointAddress = USB_DIR_IN, 449 .bmAttributes = USB_ENDPOINT_XFER_INT, 450 .wMaxPacketSize = cpu_to_le16(2), 451 .bInterval = 32, /* frames -> 32 ms */ 452}; 453 454#ifndef FSG_NO_OTG 455# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 2 456#else 457# define FSG_FS_FUNCTION_PRE_EP_ENTRIES 1 458#endif 459 460#endif 461 462static struct usb_descriptor_header *fsg_fs_function[] = { 463#ifndef FSG_NO_OTG 464 (struct usb_descriptor_header *) &fsg_otg_desc, 465#endif 466 (struct usb_descriptor_header *) &fsg_intf_desc, 467 (struct usb_descriptor_header *) &fsg_fs_bulk_in_desc, 468 (struct usb_descriptor_header *) &fsg_fs_bulk_out_desc, 469#ifndef FSG_NO_INTR_EP 470 (struct usb_descriptor_header *) &fsg_fs_intr_in_desc, 471#endif 472 NULL, 473}; 474 475 476/* 477 * USB 2.0 devices need to expose both high speed and full speed 478 * descriptors, unless they only run at full speed. 479 * 480 * That means alternate endpoint descriptors (bigger packets) 481 * and a "device qualifier" ... plus more construction options 482 * for the configuration descriptor. 483 */ 484static struct usb_endpoint_descriptor 485fsg_hs_bulk_in_desc = { 486 .bLength = USB_DT_ENDPOINT_SIZE, 487 .bDescriptorType = USB_DT_ENDPOINT, 488 489 /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */ 490 .bmAttributes = USB_ENDPOINT_XFER_BULK, 491 .wMaxPacketSize = cpu_to_le16(512), 492}; 493 494static struct usb_endpoint_descriptor 495fsg_hs_bulk_out_desc = { 496 .bLength = USB_DT_ENDPOINT_SIZE, 497 .bDescriptorType = USB_DT_ENDPOINT, 498 499 /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */ 500 .bmAttributes = USB_ENDPOINT_XFER_BULK, 501 .wMaxPacketSize = cpu_to_le16(512), 502 .bInterval = 1, /* NAK every 1 uframe */ 503}; 504 505#ifndef FSG_NO_INTR_EP 506 507static struct usb_endpoint_descriptor 508fsg_hs_intr_in_desc = { 509 .bLength = USB_DT_ENDPOINT_SIZE, 510 .bDescriptorType = USB_DT_ENDPOINT, 511 512 /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */ 513 .bmAttributes = USB_ENDPOINT_XFER_INT, 514 .wMaxPacketSize = cpu_to_le16(2), 515 .bInterval = 9, /* 2**(9-1) = 256 uframes -> 32 ms */ 516}; 517 518#ifndef FSG_NO_OTG 519# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 2 520#else 521# define FSG_HS_FUNCTION_PRE_EP_ENTRIES 1 522#endif 523 524#endif 525 526static struct usb_descriptor_header *fsg_hs_function[] = { 527#ifndef FSG_NO_OTG 528 (struct usb_descriptor_header *) &fsg_otg_desc, 529#endif 530 (struct usb_descriptor_header *) &fsg_intf_desc, 531 (struct usb_descriptor_header *) &fsg_hs_bulk_in_desc, 532 (struct usb_descriptor_header *) &fsg_hs_bulk_out_desc, 533#ifndef FSG_NO_INTR_EP 534 (struct usb_descriptor_header *) &fsg_hs_intr_in_desc, 535#endif 536 NULL, 537}; 538 539/* Maxpacket and other transfer characteristics vary by speed. */ 540static struct usb_endpoint_descriptor * 541fsg_ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs, 542 struct usb_endpoint_descriptor *hs) 543{ 544 if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH) 545 return hs; 546 return fs; 547} 548 549 550/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */ 551static struct usb_string fsg_strings[] = { 552#ifndef FSG_NO_DEVICE_STRINGS 553 {FSG_STRING_MANUFACTURER, fsg_string_manufacturer}, 554 {FSG_STRING_PRODUCT, fsg_string_product}, 555 {FSG_STRING_SERIAL, fsg_string_serial}, 556 {FSG_STRING_CONFIG, fsg_string_config}, 557#endif 558 {FSG_STRING_INTERFACE, fsg_string_interface}, 559 {} 560}; 561 562static struct usb_gadget_strings fsg_stringtab = { 563 .language = 0x0409, /* en-us */ 564 .strings = fsg_strings, 565}; 566 567 568 /*-------------------------------------------------------------------------*/ 569 570/* 571 * If the next two routines are called while the gadget is registered, 572 * the caller must own fsg->filesem for writing. 573 */ 574 575static int fsg_lun_open(struct fsg_lun *curlun, const char *filename) 576{ 577 int ro; 578 struct file *filp = NULL; 579 int rc = -EINVAL; 580 struct inode *inode = NULL; 581 loff_t size; 582 loff_t num_sectors; 583 loff_t min_sectors; 584 585 /* R/W if we can, R/O if we must */ 586 ro = curlun->initially_ro; 587 if (!ro) { 588 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0); 589 if (-EROFS == PTR_ERR(filp)) 590 ro = 1; 591 } 592 if (ro) 593 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0); 594 if (IS_ERR(filp)) { 595 LINFO(curlun, "unable to open backing file: %s\n", filename); 596 return PTR_ERR(filp); 597 } 598 599 if (!(filp->f_mode & FMODE_WRITE)) 600 ro = 1; 601 602 if (filp->f_path.dentry) 603 inode = filp->f_path.dentry->d_inode; 604 if (inode && S_ISBLK(inode->i_mode)) { 605 if (bdev_read_only(inode->i_bdev)) 606 ro = 1; 607 } else if (!inode || !S_ISREG(inode->i_mode)) { 608 LINFO(curlun, "invalid file type: %s\n", filename); 609 goto out; 610 } 611 612 /* 613 * If we can't read the file, it's no good. 614 * If we can't write the file, use it read-only. 615 */ 616 if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) { 617 LINFO(curlun, "file not readable: %s\n", filename); 618 goto out; 619 } 620 if (!(filp->f_op->write || filp->f_op->aio_write)) 621 ro = 1; 622 623 size = i_size_read(inode->i_mapping->host); 624 if (size < 0) { 625 LINFO(curlun, "unable to find file size: %s\n", filename); 626 rc = (int) size; 627 goto out; 628 } 629 num_sectors = size >> 9; /* File size in 512-byte blocks */ 630 min_sectors = 1; 631 if (curlun->cdrom) { 632 num_sectors &= ~3; /* Reduce to a multiple of 2048 */ 633 min_sectors = 300*4; /* Smallest track is 300 frames */ 634 if (num_sectors >= 256*60*75*4) { 635 num_sectors = (256*60*75 - 1) * 4; 636 LINFO(curlun, "file too big: %s\n", filename); 637 LINFO(curlun, "using only first %d blocks\n", 638 (int) num_sectors); 639 } 640 } 641 if (num_sectors < min_sectors) { 642 LINFO(curlun, "file too small: %s\n", filename); 643 rc = -ETOOSMALL; 644 goto out; 645 } 646 647 get_file(filp); 648 curlun->ro = ro; 649 curlun->filp = filp; 650 curlun->file_length = size; 651 curlun->num_sectors = num_sectors; 652 LDBG(curlun, "open backing file: %s\n", filename); 653 rc = 0; 654 655out: 656 filp_close(filp, current->files); 657 return rc; 658} 659 660 661static void fsg_lun_close(struct fsg_lun *curlun) 662{ 663 if (curlun->filp) { 664 LDBG(curlun, "close backing file\n"); 665 fput(curlun->filp); 666 curlun->filp = NULL; 667 } 668} 669 670 671/*-------------------------------------------------------------------------*/ 672 673/* 674 * Sync the file data, don't bother with the metadata. 675 * This code was copied from fs/buffer.c:sys_fdatasync(). 676 */ 677static int fsg_lun_fsync_sub(struct fsg_lun *curlun) 678{ 679 struct file *filp = curlun->filp; 680 681 if (curlun->ro || !filp) 682 return 0; 683 return vfs_fsync(filp, 1); 684} 685 686static void store_cdrom_address(u8 *dest, int msf, u32 addr) 687{ 688 if (msf) { 689 /* Convert to Minutes-Seconds-Frames */ 690 addr >>= 2; /* Convert to 2048-byte frames */ 691 addr += 2*75; /* Lead-in occupies 2 seconds */ 692 dest[3] = addr % 75; /* Frames */ 693 addr /= 75; 694 dest[2] = addr % 60; /* Seconds */ 695 addr /= 60; 696 dest[1] = addr; /* Minutes */ 697 dest[0] = 0; /* Reserved */ 698 } else { 699 /* Absolute sector */ 700 put_unaligned_be32(addr, dest); 701 } 702} 703 704 705/*-------------------------------------------------------------------------*/ 706 707 708static ssize_t fsg_show_ro(struct device *dev, struct device_attribute *attr, 709 char *buf) 710{ 711 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 712 713 return sprintf(buf, "%d\n", fsg_lun_is_open(curlun) 714 ? curlun->ro 715 : curlun->initially_ro); 716} 717 718static ssize_t fsg_show_nofua(struct device *dev, struct device_attribute *attr, 719 char *buf) 720{ 721 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 722 723 return sprintf(buf, "%u\n", curlun->nofua); 724} 725 726static ssize_t fsg_show_file(struct device *dev, struct device_attribute *attr, 727 char *buf) 728{ 729 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 730 struct rw_semaphore *filesem = dev_get_drvdata(dev); 731 char *p; 732 ssize_t rc; 733 734 down_read(filesem); 735 if (fsg_lun_is_open(curlun)) { /* Get the complete pathname */ 736 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1); 737 if (IS_ERR(p)) 738 rc = PTR_ERR(p); 739 else { 740 rc = strlen(p); 741 memmove(buf, p, rc); 742 buf[rc] = '\n'; /* Add a newline */ 743 buf[++rc] = 0; 744 } 745 } else { /* No file, return 0 bytes */ 746 *buf = 0; 747 rc = 0; 748 } 749 up_read(filesem); 750 return rc; 751} 752 753 754static ssize_t fsg_store_ro(struct device *dev, struct device_attribute *attr, 755 const char *buf, size_t count) 756{ 757 ssize_t rc = count; 758 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 759 struct rw_semaphore *filesem = dev_get_drvdata(dev); 760 unsigned long ro; 761 762 if (strict_strtoul(buf, 2, &ro)) 763 return -EINVAL; 764 765 /* 766 * Allow the write-enable status to change only while the 767 * backing file is closed. 768 */ 769 down_read(filesem); 770 if (fsg_lun_is_open(curlun)) { 771 LDBG(curlun, "read-only status change prevented\n"); 772 rc = -EBUSY; 773 } else { 774 curlun->ro = ro; 775 curlun->initially_ro = ro; 776 LDBG(curlun, "read-only status set to %d\n", curlun->ro); 777 } 778 up_read(filesem); 779 return rc; 780} 781 782static ssize_t fsg_store_nofua(struct device *dev, 783 struct device_attribute *attr, 784 const char *buf, size_t count) 785{ 786 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 787 unsigned long nofua; 788 789 if (strict_strtoul(buf, 2, &nofua)) 790 return -EINVAL; 791 792 /* Sync data when switching from async mode to sync */ 793 if (!nofua && curlun->nofua) 794 fsg_lun_fsync_sub(curlun); 795 796 curlun->nofua = nofua; 797 798 return count; 799} 800 801static ssize_t fsg_store_file(struct device *dev, struct device_attribute *attr, 802 const char *buf, size_t count) 803{ 804 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 805 struct rw_semaphore *filesem = dev_get_drvdata(dev); 806 int rc = 0; 807 808 if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) { 809 LDBG(curlun, "eject attempt prevented\n"); 810 return -EBUSY; /* "Door is locked" */ 811 } 812 813 /* Remove a trailing newline */ 814 if (count > 0 && buf[count-1] == '\n') 815 ((char *) buf)[count-1] = 0; /* Ugh! */ 816 817 /* Eject current medium */ 818 down_write(filesem); 819 if (fsg_lun_is_open(curlun)) { 820 fsg_lun_close(curlun); 821 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT; 822 } 823 824 /* Load new medium */ 825 if (count > 0 && buf[0]) { 826 rc = fsg_lun_open(curlun, buf); 827 if (rc == 0) 828 curlun->unit_attention_data = 829 SS_NOT_READY_TO_READY_TRANSITION; 830 } 831 up_write(filesem); 832 return (rc < 0 ? rc : count); 833} 834