file_storage.c revision d6181702f510302dce5666a50344b5acb196ab4e
1/* 2 * file_storage.c -- File-backed USB Storage Gadget, for USB development 3 * 4 * Copyright (C) 2003-2008 Alan Stern 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer, 12 * without modification. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The names of the above-listed copyright holders may not be used 17 * to endorse or promote products derived from this software without 18 * specific prior written permission. 19 * 20 * ALTERNATIVELY, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") as published by the Free Software 22 * Foundation, either version 2 of that License or (at your option) any 23 * later version. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 26 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 27 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 29 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 30 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 32 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 39/* 40 * The File-backed Storage Gadget acts as a USB Mass Storage device, 41 * appearing to the host as a disk drive or as a CD-ROM drive. In addition 42 * to providing an example of a genuinely useful gadget driver for a USB 43 * device, it also illustrates a technique of double-buffering for increased 44 * throughput. Last but not least, it gives an easy way to probe the 45 * behavior of the Mass Storage drivers in a USB host. 46 * 47 * Backing storage is provided by a regular file or a block device, specified 48 * by the "file" module parameter. Access can be limited to read-only by 49 * setting the optional "ro" module parameter. (For CD-ROM emulation, 50 * access is always read-only.) The gadget will indicate that it has 51 * removable media if the optional "removable" module parameter is set. 52 * 53 * The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI), 54 * and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected 55 * by the optional "transport" module parameter. It also supports the 56 * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03), 57 * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by 58 * the optional "protocol" module parameter. In addition, the default 59 * Vendor ID, Product ID, and release number can be overridden. 60 * 61 * There is support for multiple logical units (LUNs), each of which has 62 * its own backing file. The number of LUNs can be set using the optional 63 * "luns" module parameter (anywhere from 1 to 8), and the corresponding 64 * files are specified using comma-separated lists for "file" and "ro". 65 * The default number of LUNs is taken from the number of "file" elements; 66 * it is 1 if "file" is not given. If "removable" is not set then a backing 67 * file must be specified for each LUN. If it is set, then an unspecified 68 * or empty backing filename means the LUN's medium is not loaded. Ideally 69 * each LUN would be settable independently as a disk drive or a CD-ROM 70 * drive, but currently all LUNs have to be the same type. The CD-ROM 71 * emulation includes a single data track and no audio tracks; hence there 72 * need be only one backing file per LUN. Note also that the CD-ROM block 73 * length is set to 512 rather than the more common value 2048. 74 * 75 * Requirements are modest; only a bulk-in and a bulk-out endpoint are 76 * needed (an interrupt-out endpoint is also needed for CBI). The memory 77 * requirement amounts to two 16K buffers, size configurable by a parameter. 78 * Support is included for both full-speed and high-speed operation. 79 * 80 * Note that the driver is slightly non-portable in that it assumes a 81 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and 82 * interrupt-in endpoints. With most device controllers this isn't an 83 * issue, but there may be some with hardware restrictions that prevent 84 * a buffer from being used by more than one endpoint. 85 * 86 * Module options: 87 * 88 * file=filename[,filename...] 89 * Required if "removable" is not set, names of 90 * the files or block devices used for 91 * backing storage 92 * ro=b[,b...] Default false, booleans for read-only access 93 * removable Default false, boolean for removable media 94 * luns=N Default N = number of filenames, number of 95 * LUNs to support 96 * stall Default determined according to the type of 97 * USB device controller (usually true), 98 * boolean to permit the driver to halt 99 * bulk endpoints 100 * cdrom Default false, boolean for whether to emulate 101 * a CD-ROM drive 102 * transport=XXX Default BBB, transport name (CB, CBI, or BBB) 103 * protocol=YYY Default SCSI, protocol name (RBC, 8020 or 104 * ATAPI, QIC, UFI, 8070, or SCSI; 105 * also 1 - 6) 106 * vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID 107 * product=0xPPPP Default 0xa4a5 (FSG), USB Product ID 108 * release=0xRRRR Override the USB release number (bcdDevice) 109 * buflen=N Default N=16384, buffer size used (will be 110 * rounded down to a multiple of 111 * PAGE_CACHE_SIZE) 112 * 113 * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro", 114 * "removable", "luns", "stall", and "cdrom" options are available; default 115 * values are used for everything else. 116 * 117 * The pathnames of the backing files and the ro settings are available in 118 * the attribute files "file" and "ro" in the lun<n> subdirectory of the 119 * gadget's sysfs directory. If the "removable" option is set, writing to 120 * these files will simulate ejecting/loading the medium (writing an empty 121 * line means eject) and adjusting a write-enable tab. Changes to the ro 122 * setting are not allowed when the medium is loaded or if CD-ROM emulation 123 * is being used. 124 * 125 * This gadget driver is heavily based on "Gadget Zero" by David Brownell. 126 * The driver's SCSI command interface was based on the "Information 127 * technology - Small Computer System Interface - 2" document from 128 * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at 129 * <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>. The single exception 130 * is opcode 0x23 (READ FORMAT CAPACITIES), which was based on the 131 * "Universal Serial Bus Mass Storage Class UFI Command Specification" 132 * document, Revision 1.0, December 14, 1998, available at 133 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>. 134 */ 135 136 137/* 138 * Driver Design 139 * 140 * The FSG driver is fairly straightforward. There is a main kernel 141 * thread that handles most of the work. Interrupt routines field 142 * callbacks from the controller driver: bulk- and interrupt-request 143 * completion notifications, endpoint-0 events, and disconnect events. 144 * Completion events are passed to the main thread by wakeup calls. Many 145 * ep0 requests are handled at interrupt time, but SetInterface, 146 * SetConfiguration, and device reset requests are forwarded to the 147 * thread in the form of "exceptions" using SIGUSR1 signals (since they 148 * should interrupt any ongoing file I/O operations). 149 * 150 * The thread's main routine implements the standard command/data/status 151 * parts of a SCSI interaction. It and its subroutines are full of tests 152 * for pending signals/exceptions -- all this polling is necessary since 153 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an 154 * indication that the driver really wants to be running in userspace.) 155 * An important point is that so long as the thread is alive it keeps an 156 * open reference to the backing file. This will prevent unmounting 157 * the backing file's underlying filesystem and could cause problems 158 * during system shutdown, for example. To prevent such problems, the 159 * thread catches INT, TERM, and KILL signals and converts them into 160 * an EXIT exception. 161 * 162 * In normal operation the main thread is started during the gadget's 163 * fsg_bind() callback and stopped during fsg_unbind(). But it can also 164 * exit when it receives a signal, and there's no point leaving the 165 * gadget running when the thread is dead. So just before the thread 166 * exits, it deregisters the gadget driver. This makes things a little 167 * tricky: The driver is deregistered at two places, and the exiting 168 * thread can indirectly call fsg_unbind() which in turn can tell the 169 * thread to exit. The first problem is resolved through the use of the 170 * REGISTERED atomic bitflag; the driver will only be deregistered once. 171 * The second problem is resolved by having fsg_unbind() check 172 * fsg->state; it won't try to stop the thread if the state is already 173 * FSG_STATE_TERMINATED. 174 * 175 * To provide maximum throughput, the driver uses a circular pipeline of 176 * buffer heads (struct fsg_buffhd). In principle the pipeline can be 177 * arbitrarily long; in practice the benefits don't justify having more 178 * than 2 stages (i.e., double buffering). But it helps to think of the 179 * pipeline as being a long one. Each buffer head contains a bulk-in and 180 * a bulk-out request pointer (since the buffer can be used for both 181 * output and input -- directions always are given from the host's 182 * point of view) as well as a pointer to the buffer and various state 183 * variables. 184 * 185 * Use of the pipeline follows a simple protocol. There is a variable 186 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use. 187 * At any time that buffer head may still be in use from an earlier 188 * request, so each buffer head has a state variable indicating whether 189 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the 190 * buffer head to be EMPTY, filling the buffer either by file I/O or by 191 * USB I/O (during which the buffer head is BUSY), and marking the buffer 192 * head FULL when the I/O is complete. Then the buffer will be emptied 193 * (again possibly by USB I/O, during which it is marked BUSY) and 194 * finally marked EMPTY again (possibly by a completion routine). 195 * 196 * A module parameter tells the driver to avoid stalling the bulk 197 * endpoints wherever the transport specification allows. This is 198 * necessary for some UDCs like the SuperH, which cannot reliably clear a 199 * halt on a bulk endpoint. However, under certain circumstances the 200 * Bulk-only specification requires a stall. In such cases the driver 201 * will halt the endpoint and set a flag indicating that it should clear 202 * the halt in software during the next device reset. Hopefully this 203 * will permit everything to work correctly. Furthermore, although the 204 * specification allows the bulk-out endpoint to halt when the host sends 205 * too much data, implementing this would cause an unavoidable race. 206 * The driver will always use the "no-stall" approach for OUT transfers. 207 * 208 * One subtle point concerns sending status-stage responses for ep0 209 * requests. Some of these requests, such as device reset, can involve 210 * interrupting an ongoing file I/O operation, which might take an 211 * arbitrarily long time. During that delay the host might give up on 212 * the original ep0 request and issue a new one. When that happens the 213 * driver should not notify the host about completion of the original 214 * request, as the host will no longer be waiting for it. So the driver 215 * assigns to each ep0 request a unique tag, and it keeps track of the 216 * tag value of the request associated with a long-running exception 217 * (device-reset, interface-change, or configuration-change). When the 218 * exception handler is finished, the status-stage response is submitted 219 * only if the current ep0 request tag is equal to the exception request 220 * tag. Thus only the most recently received ep0 request will get a 221 * status-stage response. 222 * 223 * Warning: This driver source file is too long. It ought to be split up 224 * into a header file plus about 3 separate .c files, to handle the details 225 * of the Gadget, USB Mass Storage, and SCSI protocols. 226 */ 227 228 229/* #define VERBOSE_DEBUG */ 230/* #define DUMP_MSGS */ 231 232 233#include <linux/blkdev.h> 234#include <linux/completion.h> 235#include <linux/dcache.h> 236#include <linux/delay.h> 237#include <linux/device.h> 238#include <linux/fcntl.h> 239#include <linux/file.h> 240#include <linux/fs.h> 241#include <linux/kref.h> 242#include <linux/kthread.h> 243#include <linux/limits.h> 244#include <linux/rwsem.h> 245#include <linux/slab.h> 246#include <linux/spinlock.h> 247#include <linux/string.h> 248#include <linux/freezer.h> 249#include <linux/utsname.h> 250 251#include <linux/usb/ch9.h> 252#include <linux/usb/gadget.h> 253 254#include "gadget_chips.h" 255 256 257 258/* 259 * Kbuild is not very cooperative with respect to linking separately 260 * compiled library objects into one module. So for now we won't use 261 * separate compilation ... ensuring init/exit sections work to shrink 262 * the runtime footprint, and giving us at least some parts of what 263 * a "gcc --combine ... part1.c part2.c part3.c ... " build would. 264 */ 265#include "usbstring.c" 266#include "config.c" 267#include "epautoconf.c" 268 269/*-------------------------------------------------------------------------*/ 270 271#define DRIVER_DESC "File-backed Storage Gadget" 272#define DRIVER_NAME "g_file_storage" 273#define DRIVER_VERSION "20 November 2008" 274 275static char fsg_string_manufacturer[64]; 276static const char fsg_string_product[] = DRIVER_DESC; 277static char fsg_string_serial[13]; 278static const char fsg_string_config[] = "Self-powered"; 279static const char fsg_string_interface[] = "Mass Storage"; 280 281MODULE_DESCRIPTION(DRIVER_DESC); 282MODULE_AUTHOR("Alan Stern"); 283MODULE_LICENSE("Dual BSD/GPL"); 284 285/* Thanks to NetChip Technologies for donating this product ID. 286 * 287 * DO NOT REUSE THESE IDs with any other driver!! Ever!! 288 * Instead: allocate your own, using normal USB-IF procedures. */ 289#define FSG_VENDOR_ID 0x0525 // NetChip 290#define FSG_PRODUCT_ID 0xa4a5 // Linux-USB File-backed Storage Gadget 291 292 293/* 294 * This driver assumes self-powered hardware and has no way for users to 295 * trigger remote wakeup. It uses autoconfiguration to select endpoints 296 * and endpoint addresses. 297 */ 298 299 300/*-------------------------------------------------------------------------*/ 301 302 303/* Encapsulate the module parameter settings */ 304 305#define FSG_MAX_LUNS 8 306 307static struct { 308 char *file[FSG_MAX_LUNS]; 309 int ro[FSG_MAX_LUNS]; 310 unsigned int num_filenames; 311 unsigned int num_ros; 312 unsigned int nluns; 313 314 int removable; 315 int can_stall; 316 int cdrom; 317 318 char *transport_parm; 319 char *protocol_parm; 320 unsigned short vendor; 321 unsigned short product; 322 unsigned short release; 323 unsigned int buflen; 324 325 int transport_type; 326 char *transport_name; 327 int protocol_type; 328 char *protocol_name; 329 330} mod_data = { // Default values 331 .transport_parm = "BBB", 332 .protocol_parm = "SCSI", 333 .removable = 0, 334 .can_stall = 1, 335 .cdrom = 0, 336 .vendor = FSG_VENDOR_ID, 337 .product = FSG_PRODUCT_ID, 338 .release = 0xffff, // Use controller chip type 339 .buflen = 16384, 340 }; 341 342 343module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames, 344 S_IRUGO); 345MODULE_PARM_DESC(file, "names of backing files or devices"); 346 347module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO); 348MODULE_PARM_DESC(ro, "true to force read-only"); 349 350module_param_named(luns, mod_data.nluns, uint, S_IRUGO); 351MODULE_PARM_DESC(luns, "number of LUNs"); 352 353module_param_named(removable, mod_data.removable, bool, S_IRUGO); 354MODULE_PARM_DESC(removable, "true to simulate removable media"); 355 356module_param_named(stall, mod_data.can_stall, bool, S_IRUGO); 357MODULE_PARM_DESC(stall, "false to prevent bulk stalls"); 358 359module_param_named(cdrom, mod_data.cdrom, bool, S_IRUGO); 360MODULE_PARM_DESC(cdrom, "true to emulate cdrom instead of disk"); 361 362 363/* In the non-TEST version, only the module parameters listed above 364 * are available. */ 365#ifdef CONFIG_USB_FILE_STORAGE_TEST 366 367module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO); 368MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)"); 369 370module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO); 371MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, " 372 "8070, or SCSI)"); 373 374module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO); 375MODULE_PARM_DESC(vendor, "USB Vendor ID"); 376 377module_param_named(product, mod_data.product, ushort, S_IRUGO); 378MODULE_PARM_DESC(product, "USB Product ID"); 379 380module_param_named(release, mod_data.release, ushort, S_IRUGO); 381MODULE_PARM_DESC(release, "USB release number"); 382 383module_param_named(buflen, mod_data.buflen, uint, S_IRUGO); 384MODULE_PARM_DESC(buflen, "I/O buffer size"); 385 386#endif /* CONFIG_USB_FILE_STORAGE_TEST */ 387 388 389/* 390 * These definitions will permit the compiler to avoid generating code for 391 * parts of the driver that aren't used in the non-TEST version. Even gcc 392 * can recognize when a test of a constant expression yields a dead code 393 * path. 394 */ 395 396#ifdef CONFIG_USB_FILE_STORAGE_TEST 397 398#define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK) 399#define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI) 400#define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI) 401 402#else 403 404#define transport_is_bbb() 1 405#define transport_is_cbi() 0 406#define protocol_is_scsi() 1 407 408#endif /* CONFIG_USB_FILE_STORAGE_TEST */ 409 410 411/*-------------------------------------------------------------------------*/ 412 413#include "storage_common.c" 414 415/*-------------------------------------------------------------------------*/ 416 417 418struct fsg_dev { 419 /* lock protects: state, all the req_busy's, and cbbuf_cmnd */ 420 spinlock_t lock; 421 struct usb_gadget *gadget; 422 423 /* filesem protects: backing files in use */ 424 struct rw_semaphore filesem; 425 426 /* reference counting: wait until all LUNs are released */ 427 struct kref ref; 428 429 struct usb_ep *ep0; // Handy copy of gadget->ep0 430 struct usb_request *ep0req; // For control responses 431 unsigned int ep0_req_tag; 432 const char *ep0req_name; 433 434 struct usb_request *intreq; // For interrupt responses 435 int intreq_busy; 436 struct fsg_buffhd *intr_buffhd; 437 438 unsigned int bulk_out_maxpacket; 439 enum fsg_state state; // For exception handling 440 unsigned int exception_req_tag; 441 442 u8 config, new_config; 443 444 unsigned int running : 1; 445 unsigned int bulk_in_enabled : 1; 446 unsigned int bulk_out_enabled : 1; 447 unsigned int intr_in_enabled : 1; 448 unsigned int phase_error : 1; 449 unsigned int short_packet_received : 1; 450 unsigned int bad_lun_okay : 1; 451 452 unsigned long atomic_bitflags; 453#define REGISTERED 0 454#define IGNORE_BULK_OUT 1 455#define SUSPENDED 2 456 457 struct usb_ep *bulk_in; 458 struct usb_ep *bulk_out; 459 struct usb_ep *intr_in; 460 461 struct fsg_buffhd *next_buffhd_to_fill; 462 struct fsg_buffhd *next_buffhd_to_drain; 463 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS]; 464 465 int thread_wakeup_needed; 466 struct completion thread_notifier; 467 struct task_struct *thread_task; 468 469 int cmnd_size; 470 u8 cmnd[MAX_COMMAND_SIZE]; 471 enum data_direction data_dir; 472 u32 data_size; 473 u32 data_size_from_cmnd; 474 u32 tag; 475 unsigned int lun; 476 u32 residue; 477 u32 usb_amount_left; 478 479 /* The CB protocol offers no way for a host to know when a command 480 * has completed. As a result the next command may arrive early, 481 * and we will still have to handle it. For that reason we need 482 * a buffer to store new commands when using CB (or CBI, which 483 * does not oblige a host to wait for command completion either). */ 484 int cbbuf_cmnd_size; 485 u8 cbbuf_cmnd[MAX_COMMAND_SIZE]; 486 487 unsigned int nluns; 488 struct fsg_lun *luns; 489 struct fsg_lun *curlun; 490}; 491 492typedef void (*fsg_routine_t)(struct fsg_dev *); 493 494static int exception_in_progress(struct fsg_dev *fsg) 495{ 496 return (fsg->state > FSG_STATE_IDLE); 497} 498 499/* Make bulk-out requests be divisible by the maxpacket size */ 500static void set_bulk_out_req_length(struct fsg_dev *fsg, 501 struct fsg_buffhd *bh, unsigned int length) 502{ 503 unsigned int rem; 504 505 bh->bulk_out_intended_length = length; 506 rem = length % fsg->bulk_out_maxpacket; 507 if (rem > 0) 508 length += fsg->bulk_out_maxpacket - rem; 509 bh->outreq->length = length; 510} 511 512static struct fsg_dev *the_fsg; 513static struct usb_gadget_driver fsg_driver; 514 515 516/*-------------------------------------------------------------------------*/ 517 518static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep) 519{ 520 const char *name; 521 522 if (ep == fsg->bulk_in) 523 name = "bulk-in"; 524 else if (ep == fsg->bulk_out) 525 name = "bulk-out"; 526 else 527 name = ep->name; 528 DBG(fsg, "%s set halt\n", name); 529 return usb_ep_set_halt(ep); 530} 531 532 533/*-------------------------------------------------------------------------*/ 534 535/* 536 * DESCRIPTORS ... most are static, but strings and (full) configuration 537 * descriptors are built on demand. Also the (static) config and interface 538 * descriptors are adjusted during fsg_bind(). 539 */ 540 541/* There is only one configuration. */ 542#define CONFIG_VALUE 1 543 544static struct usb_device_descriptor 545device_desc = { 546 .bLength = sizeof device_desc, 547 .bDescriptorType = USB_DT_DEVICE, 548 549 .bcdUSB = cpu_to_le16(0x0200), 550 .bDeviceClass = USB_CLASS_PER_INTERFACE, 551 552 /* The next three values can be overridden by module parameters */ 553 .idVendor = cpu_to_le16(FSG_VENDOR_ID), 554 .idProduct = cpu_to_le16(FSG_PRODUCT_ID), 555 .bcdDevice = cpu_to_le16(0xffff), 556 557 .iManufacturer = FSG_STRING_MANUFACTURER, 558 .iProduct = FSG_STRING_PRODUCT, 559 .iSerialNumber = FSG_STRING_SERIAL, 560 .bNumConfigurations = 1, 561}; 562 563static struct usb_config_descriptor 564config_desc = { 565 .bLength = sizeof config_desc, 566 .bDescriptorType = USB_DT_CONFIG, 567 568 /* wTotalLength computed by usb_gadget_config_buf() */ 569 .bNumInterfaces = 1, 570 .bConfigurationValue = CONFIG_VALUE, 571 .iConfiguration = FSG_STRING_CONFIG, 572 .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER, 573 .bMaxPower = CONFIG_USB_GADGET_VBUS_DRAW / 2, 574}; 575 576 577static struct usb_qualifier_descriptor 578dev_qualifier = { 579 .bLength = sizeof dev_qualifier, 580 .bDescriptorType = USB_DT_DEVICE_QUALIFIER, 581 582 .bcdUSB = cpu_to_le16(0x0200), 583 .bDeviceClass = USB_CLASS_PER_INTERFACE, 584 585 .bNumConfigurations = 1, 586}; 587 588 589 590/* 591 * Config descriptors must agree with the code that sets configurations 592 * and with code managing interfaces and their altsettings. They must 593 * also handle different speeds and other-speed requests. 594 */ 595static int populate_config_buf(struct usb_gadget *gadget, 596 u8 *buf, u8 type, unsigned index) 597{ 598 enum usb_device_speed speed = gadget->speed; 599 int len; 600 const struct usb_descriptor_header **function; 601 602 if (index > 0) 603 return -EINVAL; 604 605 if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG) 606 speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed; 607 if (gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH) 608 function = fsg_hs_function; 609 else 610 function = fsg_fs_function; 611 612 /* for now, don't advertise srp-only devices */ 613 if (!gadget_is_otg(gadget)) 614 function++; 615 616 len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function); 617 ((struct usb_config_descriptor *) buf)->bDescriptorType = type; 618 return len; 619} 620 621 622/*-------------------------------------------------------------------------*/ 623 624/* These routines may be called in process context or in_irq */ 625 626/* Caller must hold fsg->lock */ 627static void wakeup_thread(struct fsg_dev *fsg) 628{ 629 /* Tell the main thread that something has happened */ 630 fsg->thread_wakeup_needed = 1; 631 if (fsg->thread_task) 632 wake_up_process(fsg->thread_task); 633} 634 635 636static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state) 637{ 638 unsigned long flags; 639 640 /* Do nothing if a higher-priority exception is already in progress. 641 * If a lower-or-equal priority exception is in progress, preempt it 642 * and notify the main thread by sending it a signal. */ 643 spin_lock_irqsave(&fsg->lock, flags); 644 if (fsg->state <= new_state) { 645 fsg->exception_req_tag = fsg->ep0_req_tag; 646 fsg->state = new_state; 647 if (fsg->thread_task) 648 send_sig_info(SIGUSR1, SEND_SIG_FORCED, 649 fsg->thread_task); 650 } 651 spin_unlock_irqrestore(&fsg->lock, flags); 652} 653 654 655/*-------------------------------------------------------------------------*/ 656 657/* The disconnect callback and ep0 routines. These always run in_irq, 658 * except that ep0_queue() is called in the main thread to acknowledge 659 * completion of various requests: set config, set interface, and 660 * Bulk-only device reset. */ 661 662static void fsg_disconnect(struct usb_gadget *gadget) 663{ 664 struct fsg_dev *fsg = get_gadget_data(gadget); 665 666 DBG(fsg, "disconnect or port reset\n"); 667 raise_exception(fsg, FSG_STATE_DISCONNECT); 668} 669 670 671static int ep0_queue(struct fsg_dev *fsg) 672{ 673 int rc; 674 675 rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC); 676 if (rc != 0 && rc != -ESHUTDOWN) { 677 678 /* We can't do much more than wait for a reset */ 679 WARNING(fsg, "error in submission: %s --> %d\n", 680 fsg->ep0->name, rc); 681 } 682 return rc; 683} 684 685static void ep0_complete(struct usb_ep *ep, struct usb_request *req) 686{ 687 struct fsg_dev *fsg = ep->driver_data; 688 689 if (req->actual > 0) 690 dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual); 691 if (req->status || req->actual != req->length) 692 DBG(fsg, "%s --> %d, %u/%u\n", __func__, 693 req->status, req->actual, req->length); 694 if (req->status == -ECONNRESET) // Request was cancelled 695 usb_ep_fifo_flush(ep); 696 697 if (req->status == 0 && req->context) 698 ((fsg_routine_t) (req->context))(fsg); 699} 700 701 702/*-------------------------------------------------------------------------*/ 703 704/* Bulk and interrupt endpoint completion handlers. 705 * These always run in_irq. */ 706 707static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req) 708{ 709 struct fsg_dev *fsg = ep->driver_data; 710 struct fsg_buffhd *bh = req->context; 711 712 if (req->status || req->actual != req->length) 713 DBG(fsg, "%s --> %d, %u/%u\n", __func__, 714 req->status, req->actual, req->length); 715 if (req->status == -ECONNRESET) // Request was cancelled 716 usb_ep_fifo_flush(ep); 717 718 /* Hold the lock while we update the request and buffer states */ 719 smp_wmb(); 720 spin_lock(&fsg->lock); 721 bh->inreq_busy = 0; 722 bh->state = BUF_STATE_EMPTY; 723 wakeup_thread(fsg); 724 spin_unlock(&fsg->lock); 725} 726 727static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req) 728{ 729 struct fsg_dev *fsg = ep->driver_data; 730 struct fsg_buffhd *bh = req->context; 731 732 dump_msg(fsg, "bulk-out", req->buf, req->actual); 733 if (req->status || req->actual != bh->bulk_out_intended_length) 734 DBG(fsg, "%s --> %d, %u/%u\n", __func__, 735 req->status, req->actual, 736 bh->bulk_out_intended_length); 737 if (req->status == -ECONNRESET) // Request was cancelled 738 usb_ep_fifo_flush(ep); 739 740 /* Hold the lock while we update the request and buffer states */ 741 smp_wmb(); 742 spin_lock(&fsg->lock); 743 bh->outreq_busy = 0; 744 bh->state = BUF_STATE_FULL; 745 wakeup_thread(fsg); 746 spin_unlock(&fsg->lock); 747} 748 749 750#ifdef CONFIG_USB_FILE_STORAGE_TEST 751static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) 752{ 753 struct fsg_dev *fsg = ep->driver_data; 754 struct fsg_buffhd *bh = req->context; 755 756 if (req->status || req->actual != req->length) 757 DBG(fsg, "%s --> %d, %u/%u\n", __func__, 758 req->status, req->actual, req->length); 759 if (req->status == -ECONNRESET) // Request was cancelled 760 usb_ep_fifo_flush(ep); 761 762 /* Hold the lock while we update the request and buffer states */ 763 smp_wmb(); 764 spin_lock(&fsg->lock); 765 fsg->intreq_busy = 0; 766 bh->state = BUF_STATE_EMPTY; 767 wakeup_thread(fsg); 768 spin_unlock(&fsg->lock); 769} 770 771#else 772static void intr_in_complete(struct usb_ep *ep, struct usb_request *req) 773{} 774#endif /* CONFIG_USB_FILE_STORAGE_TEST */ 775 776 777/*-------------------------------------------------------------------------*/ 778 779/* Ep0 class-specific handlers. These always run in_irq. */ 780 781#ifdef CONFIG_USB_FILE_STORAGE_TEST 782static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) 783{ 784 struct usb_request *req = fsg->ep0req; 785 static u8 cbi_reset_cmnd[6] = { 786 SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff}; 787 788 /* Error in command transfer? */ 789 if (req->status || req->length != req->actual || 790 req->actual < 6 || req->actual > MAX_COMMAND_SIZE) { 791 792 /* Not all controllers allow a protocol stall after 793 * receiving control-out data, but we'll try anyway. */ 794 fsg_set_halt(fsg, fsg->ep0); 795 return; // Wait for reset 796 } 797 798 /* Is it the special reset command? */ 799 if (req->actual >= sizeof cbi_reset_cmnd && 800 memcmp(req->buf, cbi_reset_cmnd, 801 sizeof cbi_reset_cmnd) == 0) { 802 803 /* Raise an exception to stop the current operation 804 * and reinitialize our state. */ 805 DBG(fsg, "cbi reset request\n"); 806 raise_exception(fsg, FSG_STATE_RESET); 807 return; 808 } 809 810 VDBG(fsg, "CB[I] accept device-specific command\n"); 811 spin_lock(&fsg->lock); 812 813 /* Save the command for later */ 814 if (fsg->cbbuf_cmnd_size) 815 WARNING(fsg, "CB[I] overwriting previous command\n"); 816 fsg->cbbuf_cmnd_size = req->actual; 817 memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size); 818 819 wakeup_thread(fsg); 820 spin_unlock(&fsg->lock); 821} 822 823#else 824static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh) 825{} 826#endif /* CONFIG_USB_FILE_STORAGE_TEST */ 827 828 829static int class_setup_req(struct fsg_dev *fsg, 830 const struct usb_ctrlrequest *ctrl) 831{ 832 struct usb_request *req = fsg->ep0req; 833 int value = -EOPNOTSUPP; 834 u16 w_index = le16_to_cpu(ctrl->wIndex); 835 u16 w_value = le16_to_cpu(ctrl->wValue); 836 u16 w_length = le16_to_cpu(ctrl->wLength); 837 838 if (!fsg->config) 839 return value; 840 841 /* Handle Bulk-only class-specific requests */ 842 if (transport_is_bbb()) { 843 switch (ctrl->bRequest) { 844 845 case USB_BULK_RESET_REQUEST: 846 if (ctrl->bRequestType != (USB_DIR_OUT | 847 USB_TYPE_CLASS | USB_RECIP_INTERFACE)) 848 break; 849 if (w_index != 0 || w_value != 0) { 850 value = -EDOM; 851 break; 852 } 853 854 /* Raise an exception to stop the current operation 855 * and reinitialize our state. */ 856 DBG(fsg, "bulk reset request\n"); 857 raise_exception(fsg, FSG_STATE_RESET); 858 value = DELAYED_STATUS; 859 break; 860 861 case USB_BULK_GET_MAX_LUN_REQUEST: 862 if (ctrl->bRequestType != (USB_DIR_IN | 863 USB_TYPE_CLASS | USB_RECIP_INTERFACE)) 864 break; 865 if (w_index != 0 || w_value != 0) { 866 value = -EDOM; 867 break; 868 } 869 VDBG(fsg, "get max LUN\n"); 870 *(u8 *) req->buf = fsg->nluns - 1; 871 value = 1; 872 break; 873 } 874 } 875 876 /* Handle CBI class-specific requests */ 877 else { 878 switch (ctrl->bRequest) { 879 880 case USB_CBI_ADSC_REQUEST: 881 if (ctrl->bRequestType != (USB_DIR_OUT | 882 USB_TYPE_CLASS | USB_RECIP_INTERFACE)) 883 break; 884 if (w_index != 0 || w_value != 0) { 885 value = -EDOM; 886 break; 887 } 888 if (w_length > MAX_COMMAND_SIZE) { 889 value = -EOVERFLOW; 890 break; 891 } 892 value = w_length; 893 fsg->ep0req->context = received_cbi_adsc; 894 break; 895 } 896 } 897 898 if (value == -EOPNOTSUPP) 899 VDBG(fsg, 900 "unknown class-specific control req " 901 "%02x.%02x v%04x i%04x l%u\n", 902 ctrl->bRequestType, ctrl->bRequest, 903 le16_to_cpu(ctrl->wValue), w_index, w_length); 904 return value; 905} 906 907 908/*-------------------------------------------------------------------------*/ 909 910/* Ep0 standard request handlers. These always run in_irq. */ 911 912static int standard_setup_req(struct fsg_dev *fsg, 913 const struct usb_ctrlrequest *ctrl) 914{ 915 struct usb_request *req = fsg->ep0req; 916 int value = -EOPNOTSUPP; 917 u16 w_index = le16_to_cpu(ctrl->wIndex); 918 u16 w_value = le16_to_cpu(ctrl->wValue); 919 920 /* Usually this just stores reply data in the pre-allocated ep0 buffer, 921 * but config change events will also reconfigure hardware. */ 922 switch (ctrl->bRequest) { 923 924 case USB_REQ_GET_DESCRIPTOR: 925 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | 926 USB_RECIP_DEVICE)) 927 break; 928 switch (w_value >> 8) { 929 930 case USB_DT_DEVICE: 931 VDBG(fsg, "get device descriptor\n"); 932 value = sizeof device_desc; 933 memcpy(req->buf, &device_desc, value); 934 break; 935 case USB_DT_DEVICE_QUALIFIER: 936 VDBG(fsg, "get device qualifier\n"); 937 if (!gadget_is_dualspeed(fsg->gadget)) 938 break; 939 value = sizeof dev_qualifier; 940 memcpy(req->buf, &dev_qualifier, value); 941 break; 942 943 case USB_DT_OTHER_SPEED_CONFIG: 944 VDBG(fsg, "get other-speed config descriptor\n"); 945 if (!gadget_is_dualspeed(fsg->gadget)) 946 break; 947 goto get_config; 948 case USB_DT_CONFIG: 949 VDBG(fsg, "get configuration descriptor\n"); 950get_config: 951 value = populate_config_buf(fsg->gadget, 952 req->buf, 953 w_value >> 8, 954 w_value & 0xff); 955 break; 956 957 case USB_DT_STRING: 958 VDBG(fsg, "get string descriptor\n"); 959 960 /* wIndex == language code */ 961 value = usb_gadget_get_string(&fsg_stringtab, 962 w_value & 0xff, req->buf); 963 break; 964 } 965 break; 966 967 /* One config, two speeds */ 968 case USB_REQ_SET_CONFIGURATION: 969 if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD | 970 USB_RECIP_DEVICE)) 971 break; 972 VDBG(fsg, "set configuration\n"); 973 if (w_value == CONFIG_VALUE || w_value == 0) { 974 fsg->new_config = w_value; 975 976 /* Raise an exception to wipe out previous transaction 977 * state (queued bufs, etc) and set the new config. */ 978 raise_exception(fsg, FSG_STATE_CONFIG_CHANGE); 979 value = DELAYED_STATUS; 980 } 981 break; 982 case USB_REQ_GET_CONFIGURATION: 983 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | 984 USB_RECIP_DEVICE)) 985 break; 986 VDBG(fsg, "get configuration\n"); 987 *(u8 *) req->buf = fsg->config; 988 value = 1; 989 break; 990 991 case USB_REQ_SET_INTERFACE: 992 if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD | 993 USB_RECIP_INTERFACE)) 994 break; 995 if (fsg->config && w_index == 0) { 996 997 /* Raise an exception to wipe out previous transaction 998 * state (queued bufs, etc) and install the new 999 * interface altsetting. */ 1000 raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE); 1001 value = DELAYED_STATUS; 1002 } 1003 break; 1004 case USB_REQ_GET_INTERFACE: 1005 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD | 1006 USB_RECIP_INTERFACE)) 1007 break; 1008 if (!fsg->config) 1009 break; 1010 if (w_index != 0) { 1011 value = -EDOM; 1012 break; 1013 } 1014 VDBG(fsg, "get interface\n"); 1015 *(u8 *) req->buf = 0; 1016 value = 1; 1017 break; 1018 1019 default: 1020 VDBG(fsg, 1021 "unknown control req %02x.%02x v%04x i%04x l%u\n", 1022 ctrl->bRequestType, ctrl->bRequest, 1023 w_value, w_index, le16_to_cpu(ctrl->wLength)); 1024 } 1025 1026 return value; 1027} 1028 1029 1030static int fsg_setup(struct usb_gadget *gadget, 1031 const struct usb_ctrlrequest *ctrl) 1032{ 1033 struct fsg_dev *fsg = get_gadget_data(gadget); 1034 int rc; 1035 int w_length = le16_to_cpu(ctrl->wLength); 1036 1037 ++fsg->ep0_req_tag; // Record arrival of a new request 1038 fsg->ep0req->context = NULL; 1039 fsg->ep0req->length = 0; 1040 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl)); 1041 1042 if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) 1043 rc = class_setup_req(fsg, ctrl); 1044 else 1045 rc = standard_setup_req(fsg, ctrl); 1046 1047 /* Respond with data/status or defer until later? */ 1048 if (rc >= 0 && rc != DELAYED_STATUS) { 1049 rc = min(rc, w_length); 1050 fsg->ep0req->length = rc; 1051 fsg->ep0req->zero = rc < w_length; 1052 fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ? 1053 "ep0-in" : "ep0-out"); 1054 rc = ep0_queue(fsg); 1055 } 1056 1057 /* Device either stalls (rc < 0) or reports success */ 1058 return rc; 1059} 1060 1061 1062/*-------------------------------------------------------------------------*/ 1063 1064/* All the following routines run in process context */ 1065 1066 1067/* Use this for bulk or interrupt transfers, not ep0 */ 1068static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep, 1069 struct usb_request *req, int *pbusy, 1070 enum fsg_buffer_state *state) 1071{ 1072 int rc; 1073 1074 if (ep == fsg->bulk_in) 1075 dump_msg(fsg, "bulk-in", req->buf, req->length); 1076 else if (ep == fsg->intr_in) 1077 dump_msg(fsg, "intr-in", req->buf, req->length); 1078 1079 spin_lock_irq(&fsg->lock); 1080 *pbusy = 1; 1081 *state = BUF_STATE_BUSY; 1082 spin_unlock_irq(&fsg->lock); 1083 rc = usb_ep_queue(ep, req, GFP_KERNEL); 1084 if (rc != 0) { 1085 *pbusy = 0; 1086 *state = BUF_STATE_EMPTY; 1087 1088 /* We can't do much more than wait for a reset */ 1089 1090 /* Note: currently the net2280 driver fails zero-length 1091 * submissions if DMA is enabled. */ 1092 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP && 1093 req->length == 0)) 1094 WARNING(fsg, "error in submission: %s --> %d\n", 1095 ep->name, rc); 1096 } 1097} 1098 1099 1100static int sleep_thread(struct fsg_dev *fsg) 1101{ 1102 int rc = 0; 1103 1104 /* Wait until a signal arrives or we are woken up */ 1105 for (;;) { 1106 try_to_freeze(); 1107 set_current_state(TASK_INTERRUPTIBLE); 1108 if (signal_pending(current)) { 1109 rc = -EINTR; 1110 break; 1111 } 1112 if (fsg->thread_wakeup_needed) 1113 break; 1114 schedule(); 1115 } 1116 __set_current_state(TASK_RUNNING); 1117 fsg->thread_wakeup_needed = 0; 1118 return rc; 1119} 1120 1121 1122/*-------------------------------------------------------------------------*/ 1123 1124static int do_read(struct fsg_dev *fsg) 1125{ 1126 struct fsg_lun *curlun = fsg->curlun; 1127 u32 lba; 1128 struct fsg_buffhd *bh; 1129 int rc; 1130 u32 amount_left; 1131 loff_t file_offset, file_offset_tmp; 1132 unsigned int amount; 1133 unsigned int partial_page; 1134 ssize_t nread; 1135 1136 /* Get the starting Logical Block Address and check that it's 1137 * not too big */ 1138 if (fsg->cmnd[0] == SC_READ_6) 1139 lba = get_unaligned_be24(&fsg->cmnd[1]); 1140 else { 1141 lba = get_unaligned_be32(&fsg->cmnd[2]); 1142 1143 /* We allow DPO (Disable Page Out = don't save data in the 1144 * cache) and FUA (Force Unit Access = don't read from the 1145 * cache), but we don't implement them. */ 1146 if ((fsg->cmnd[1] & ~0x18) != 0) { 1147 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1148 return -EINVAL; 1149 } 1150 } 1151 if (lba >= curlun->num_sectors) { 1152 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1153 return -EINVAL; 1154 } 1155 file_offset = ((loff_t) lba) << 9; 1156 1157 /* Carry out the file reads */ 1158 amount_left = fsg->data_size_from_cmnd; 1159 if (unlikely(amount_left == 0)) 1160 return -EIO; // No default reply 1161 1162 for (;;) { 1163 1164 /* Figure out how much we need to read: 1165 * Try to read the remaining amount. 1166 * But don't read more than the buffer size. 1167 * And don't try to read past the end of the file. 1168 * Finally, if we're not at a page boundary, don't read past 1169 * the next page. 1170 * If this means reading 0 then we were asked to read past 1171 * the end of file. */ 1172 amount = min((unsigned int) amount_left, mod_data.buflen); 1173 amount = min((loff_t) amount, 1174 curlun->file_length - file_offset); 1175 partial_page = file_offset & (PAGE_CACHE_SIZE - 1); 1176 if (partial_page > 0) 1177 amount = min(amount, (unsigned int) PAGE_CACHE_SIZE - 1178 partial_page); 1179 1180 /* Wait for the next buffer to become available */ 1181 bh = fsg->next_buffhd_to_fill; 1182 while (bh->state != BUF_STATE_EMPTY) { 1183 rc = sleep_thread(fsg); 1184 if (rc) 1185 return rc; 1186 } 1187 1188 /* If we were asked to read past the end of file, 1189 * end with an empty buffer. */ 1190 if (amount == 0) { 1191 curlun->sense_data = 1192 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1193 curlun->sense_data_info = file_offset >> 9; 1194 curlun->info_valid = 1; 1195 bh->inreq->length = 0; 1196 bh->state = BUF_STATE_FULL; 1197 break; 1198 } 1199 1200 /* Perform the read */ 1201 file_offset_tmp = file_offset; 1202 nread = vfs_read(curlun->filp, 1203 (char __user *) bh->buf, 1204 amount, &file_offset_tmp); 1205 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount, 1206 (unsigned long long) file_offset, 1207 (int) nread); 1208 if (signal_pending(current)) 1209 return -EINTR; 1210 1211 if (nread < 0) { 1212 LDBG(curlun, "error in file read: %d\n", 1213 (int) nread); 1214 nread = 0; 1215 } else if (nread < amount) { 1216 LDBG(curlun, "partial file read: %d/%u\n", 1217 (int) nread, amount); 1218 nread -= (nread & 511); // Round down to a block 1219 } 1220 file_offset += nread; 1221 amount_left -= nread; 1222 fsg->residue -= nread; 1223 bh->inreq->length = nread; 1224 bh->state = BUF_STATE_FULL; 1225 1226 /* If an error occurred, report it and its position */ 1227 if (nread < amount) { 1228 curlun->sense_data = SS_UNRECOVERED_READ_ERROR; 1229 curlun->sense_data_info = file_offset >> 9; 1230 curlun->info_valid = 1; 1231 break; 1232 } 1233 1234 if (amount_left == 0) 1235 break; // No more left to read 1236 1237 /* Send this buffer and go read some more */ 1238 bh->inreq->zero = 0; 1239 start_transfer(fsg, fsg->bulk_in, bh->inreq, 1240 &bh->inreq_busy, &bh->state); 1241 fsg->next_buffhd_to_fill = bh->next; 1242 } 1243 1244 return -EIO; // No default reply 1245} 1246 1247 1248/*-------------------------------------------------------------------------*/ 1249 1250static int do_write(struct fsg_dev *fsg) 1251{ 1252 struct fsg_lun *curlun = fsg->curlun; 1253 u32 lba; 1254 struct fsg_buffhd *bh; 1255 int get_some_more; 1256 u32 amount_left_to_req, amount_left_to_write; 1257 loff_t usb_offset, file_offset, file_offset_tmp; 1258 unsigned int amount; 1259 unsigned int partial_page; 1260 ssize_t nwritten; 1261 int rc; 1262 1263 if (curlun->ro) { 1264 curlun->sense_data = SS_WRITE_PROTECTED; 1265 return -EINVAL; 1266 } 1267 spin_lock(&curlun->filp->f_lock); 1268 curlun->filp->f_flags &= ~O_SYNC; // Default is not to wait 1269 spin_unlock(&curlun->filp->f_lock); 1270 1271 /* Get the starting Logical Block Address and check that it's 1272 * not too big */ 1273 if (fsg->cmnd[0] == SC_WRITE_6) 1274 lba = get_unaligned_be24(&fsg->cmnd[1]); 1275 else { 1276 lba = get_unaligned_be32(&fsg->cmnd[2]); 1277 1278 /* We allow DPO (Disable Page Out = don't save data in the 1279 * cache) and FUA (Force Unit Access = write directly to the 1280 * medium). We don't implement DPO; we implement FUA by 1281 * performing synchronous output. */ 1282 if ((fsg->cmnd[1] & ~0x18) != 0) { 1283 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1284 return -EINVAL; 1285 } 1286 if (fsg->cmnd[1] & 0x08) { // FUA 1287 spin_lock(&curlun->filp->f_lock); 1288 curlun->filp->f_flags |= O_SYNC; 1289 spin_unlock(&curlun->filp->f_lock); 1290 } 1291 } 1292 if (lba >= curlun->num_sectors) { 1293 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1294 return -EINVAL; 1295 } 1296 1297 /* Carry out the file writes */ 1298 get_some_more = 1; 1299 file_offset = usb_offset = ((loff_t) lba) << 9; 1300 amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd; 1301 1302 while (amount_left_to_write > 0) { 1303 1304 /* Queue a request for more data from the host */ 1305 bh = fsg->next_buffhd_to_fill; 1306 if (bh->state == BUF_STATE_EMPTY && get_some_more) { 1307 1308 /* Figure out how much we want to get: 1309 * Try to get the remaining amount. 1310 * But don't get more than the buffer size. 1311 * And don't try to go past the end of the file. 1312 * If we're not at a page boundary, 1313 * don't go past the next page. 1314 * If this means getting 0, then we were asked 1315 * to write past the end of file. 1316 * Finally, round down to a block boundary. */ 1317 amount = min(amount_left_to_req, mod_data.buflen); 1318 amount = min((loff_t) amount, curlun->file_length - 1319 usb_offset); 1320 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1); 1321 if (partial_page > 0) 1322 amount = min(amount, 1323 (unsigned int) PAGE_CACHE_SIZE - partial_page); 1324 1325 if (amount == 0) { 1326 get_some_more = 0; 1327 curlun->sense_data = 1328 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1329 curlun->sense_data_info = usb_offset >> 9; 1330 curlun->info_valid = 1; 1331 continue; 1332 } 1333 amount -= (amount & 511); 1334 if (amount == 0) { 1335 1336 /* Why were we were asked to transfer a 1337 * partial block? */ 1338 get_some_more = 0; 1339 continue; 1340 } 1341 1342 /* Get the next buffer */ 1343 usb_offset += amount; 1344 fsg->usb_amount_left -= amount; 1345 amount_left_to_req -= amount; 1346 if (amount_left_to_req == 0) 1347 get_some_more = 0; 1348 1349 /* amount is always divisible by 512, hence by 1350 * the bulk-out maxpacket size */ 1351 bh->outreq->length = bh->bulk_out_intended_length = 1352 amount; 1353 bh->outreq->short_not_ok = 1; 1354 start_transfer(fsg, fsg->bulk_out, bh->outreq, 1355 &bh->outreq_busy, &bh->state); 1356 fsg->next_buffhd_to_fill = bh->next; 1357 continue; 1358 } 1359 1360 /* Write the received data to the backing file */ 1361 bh = fsg->next_buffhd_to_drain; 1362 if (bh->state == BUF_STATE_EMPTY && !get_some_more) 1363 break; // We stopped early 1364 if (bh->state == BUF_STATE_FULL) { 1365 smp_rmb(); 1366 fsg->next_buffhd_to_drain = bh->next; 1367 bh->state = BUF_STATE_EMPTY; 1368 1369 /* Did something go wrong with the transfer? */ 1370 if (bh->outreq->status != 0) { 1371 curlun->sense_data = SS_COMMUNICATION_FAILURE; 1372 curlun->sense_data_info = file_offset >> 9; 1373 curlun->info_valid = 1; 1374 break; 1375 } 1376 1377 amount = bh->outreq->actual; 1378 if (curlun->file_length - file_offset < amount) { 1379 LERROR(curlun, 1380 "write %u @ %llu beyond end %llu\n", 1381 amount, (unsigned long long) file_offset, 1382 (unsigned long long) curlun->file_length); 1383 amount = curlun->file_length - file_offset; 1384 } 1385 1386 /* Perform the write */ 1387 file_offset_tmp = file_offset; 1388 nwritten = vfs_write(curlun->filp, 1389 (char __user *) bh->buf, 1390 amount, &file_offset_tmp); 1391 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount, 1392 (unsigned long long) file_offset, 1393 (int) nwritten); 1394 if (signal_pending(current)) 1395 return -EINTR; // Interrupted! 1396 1397 if (nwritten < 0) { 1398 LDBG(curlun, "error in file write: %d\n", 1399 (int) nwritten); 1400 nwritten = 0; 1401 } else if (nwritten < amount) { 1402 LDBG(curlun, "partial file write: %d/%u\n", 1403 (int) nwritten, amount); 1404 nwritten -= (nwritten & 511); 1405 // Round down to a block 1406 } 1407 file_offset += nwritten; 1408 amount_left_to_write -= nwritten; 1409 fsg->residue -= nwritten; 1410 1411 /* If an error occurred, report it and its position */ 1412 if (nwritten < amount) { 1413 curlun->sense_data = SS_WRITE_ERROR; 1414 curlun->sense_data_info = file_offset >> 9; 1415 curlun->info_valid = 1; 1416 break; 1417 } 1418 1419 /* Did the host decide to stop early? */ 1420 if (bh->outreq->actual != bh->outreq->length) { 1421 fsg->short_packet_received = 1; 1422 break; 1423 } 1424 continue; 1425 } 1426 1427 /* Wait for something to happen */ 1428 rc = sleep_thread(fsg); 1429 if (rc) 1430 return rc; 1431 } 1432 1433 return -EIO; // No default reply 1434} 1435 1436 1437/*-------------------------------------------------------------------------*/ 1438 1439static int do_synchronize_cache(struct fsg_dev *fsg) 1440{ 1441 struct fsg_lun *curlun = fsg->curlun; 1442 int rc; 1443 1444 /* We ignore the requested LBA and write out all file's 1445 * dirty data buffers. */ 1446 rc = fsg_lun_fsync_sub(curlun); 1447 if (rc) 1448 curlun->sense_data = SS_WRITE_ERROR; 1449 return 0; 1450} 1451 1452 1453/*-------------------------------------------------------------------------*/ 1454 1455static void invalidate_sub(struct fsg_lun *curlun) 1456{ 1457 struct file *filp = curlun->filp; 1458 struct inode *inode = filp->f_path.dentry->d_inode; 1459 unsigned long rc; 1460 1461 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1); 1462 VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc); 1463} 1464 1465static int do_verify(struct fsg_dev *fsg) 1466{ 1467 struct fsg_lun *curlun = fsg->curlun; 1468 u32 lba; 1469 u32 verification_length; 1470 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; 1471 loff_t file_offset, file_offset_tmp; 1472 u32 amount_left; 1473 unsigned int amount; 1474 ssize_t nread; 1475 1476 /* Get the starting Logical Block Address and check that it's 1477 * not too big */ 1478 lba = get_unaligned_be32(&fsg->cmnd[2]); 1479 if (lba >= curlun->num_sectors) { 1480 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1481 return -EINVAL; 1482 } 1483 1484 /* We allow DPO (Disable Page Out = don't save data in the 1485 * cache) but we don't implement it. */ 1486 if ((fsg->cmnd[1] & ~0x10) != 0) { 1487 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1488 return -EINVAL; 1489 } 1490 1491 verification_length = get_unaligned_be16(&fsg->cmnd[7]); 1492 if (unlikely(verification_length == 0)) 1493 return -EIO; // No default reply 1494 1495 /* Prepare to carry out the file verify */ 1496 amount_left = verification_length << 9; 1497 file_offset = ((loff_t) lba) << 9; 1498 1499 /* Write out all the dirty buffers before invalidating them */ 1500 fsg_lun_fsync_sub(curlun); 1501 if (signal_pending(current)) 1502 return -EINTR; 1503 1504 invalidate_sub(curlun); 1505 if (signal_pending(current)) 1506 return -EINTR; 1507 1508 /* Just try to read the requested blocks */ 1509 while (amount_left > 0) { 1510 1511 /* Figure out how much we need to read: 1512 * Try to read the remaining amount, but not more than 1513 * the buffer size. 1514 * And don't try to read past the end of the file. 1515 * If this means reading 0 then we were asked to read 1516 * past the end of file. */ 1517 amount = min((unsigned int) amount_left, mod_data.buflen); 1518 amount = min((loff_t) amount, 1519 curlun->file_length - file_offset); 1520 if (amount == 0) { 1521 curlun->sense_data = 1522 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1523 curlun->sense_data_info = file_offset >> 9; 1524 curlun->info_valid = 1; 1525 break; 1526 } 1527 1528 /* Perform the read */ 1529 file_offset_tmp = file_offset; 1530 nread = vfs_read(curlun->filp, 1531 (char __user *) bh->buf, 1532 amount, &file_offset_tmp); 1533 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount, 1534 (unsigned long long) file_offset, 1535 (int) nread); 1536 if (signal_pending(current)) 1537 return -EINTR; 1538 1539 if (nread < 0) { 1540 LDBG(curlun, "error in file verify: %d\n", 1541 (int) nread); 1542 nread = 0; 1543 } else if (nread < amount) { 1544 LDBG(curlun, "partial file verify: %d/%u\n", 1545 (int) nread, amount); 1546 nread -= (nread & 511); // Round down to a sector 1547 } 1548 if (nread == 0) { 1549 curlun->sense_data = SS_UNRECOVERED_READ_ERROR; 1550 curlun->sense_data_info = file_offset >> 9; 1551 curlun->info_valid = 1; 1552 break; 1553 } 1554 file_offset += nread; 1555 amount_left -= nread; 1556 } 1557 return 0; 1558} 1559 1560 1561/*-------------------------------------------------------------------------*/ 1562 1563static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1564{ 1565 u8 *buf = (u8 *) bh->buf; 1566 1567 static char vendor_id[] = "Linux "; 1568 static char product_disk_id[] = "File-Stor Gadget"; 1569 static char product_cdrom_id[] = "File-CD Gadget "; 1570 1571 if (!fsg->curlun) { // Unsupported LUNs are okay 1572 fsg->bad_lun_okay = 1; 1573 memset(buf, 0, 36); 1574 buf[0] = 0x7f; // Unsupported, no device-type 1575 buf[4] = 31; // Additional length 1576 return 36; 1577 } 1578 1579 memset(buf, 0, 8); 1580 buf[0] = (mod_data.cdrom ? TYPE_CDROM : TYPE_DISK); 1581 if (mod_data.removable) 1582 buf[1] = 0x80; 1583 buf[2] = 2; // ANSI SCSI level 2 1584 buf[3] = 2; // SCSI-2 INQUIRY data format 1585 buf[4] = 31; // Additional length 1586 // No special options 1587 sprintf(buf + 8, "%-8s%-16s%04x", vendor_id, 1588 (mod_data.cdrom ? product_cdrom_id : 1589 product_disk_id), 1590 mod_data.release); 1591 return 36; 1592} 1593 1594 1595static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1596{ 1597 struct fsg_lun *curlun = fsg->curlun; 1598 u8 *buf = (u8 *) bh->buf; 1599 u32 sd, sdinfo; 1600 int valid; 1601 1602 /* 1603 * From the SCSI-2 spec., section 7.9 (Unit attention condition): 1604 * 1605 * If a REQUEST SENSE command is received from an initiator 1606 * with a pending unit attention condition (before the target 1607 * generates the contingent allegiance condition), then the 1608 * target shall either: 1609 * a) report any pending sense data and preserve the unit 1610 * attention condition on the logical unit, or, 1611 * b) report the unit attention condition, may discard any 1612 * pending sense data, and clear the unit attention 1613 * condition on the logical unit for that initiator. 1614 * 1615 * FSG normally uses option a); enable this code to use option b). 1616 */ 1617#if 0 1618 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) { 1619 curlun->sense_data = curlun->unit_attention_data; 1620 curlun->unit_attention_data = SS_NO_SENSE; 1621 } 1622#endif 1623 1624 if (!curlun) { // Unsupported LUNs are okay 1625 fsg->bad_lun_okay = 1; 1626 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; 1627 sdinfo = 0; 1628 valid = 0; 1629 } else { 1630 sd = curlun->sense_data; 1631 sdinfo = curlun->sense_data_info; 1632 valid = curlun->info_valid << 7; 1633 curlun->sense_data = SS_NO_SENSE; 1634 curlun->sense_data_info = 0; 1635 curlun->info_valid = 0; 1636 } 1637 1638 memset(buf, 0, 18); 1639 buf[0] = valid | 0x70; // Valid, current error 1640 buf[2] = SK(sd); 1641 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */ 1642 buf[7] = 18 - 8; // Additional sense length 1643 buf[12] = ASC(sd); 1644 buf[13] = ASCQ(sd); 1645 return 18; 1646} 1647 1648 1649static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1650{ 1651 struct fsg_lun *curlun = fsg->curlun; 1652 u32 lba = get_unaligned_be32(&fsg->cmnd[2]); 1653 int pmi = fsg->cmnd[8]; 1654 u8 *buf = (u8 *) bh->buf; 1655 1656 /* Check the PMI and LBA fields */ 1657 if (pmi > 1 || (pmi == 0 && lba != 0)) { 1658 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1659 return -EINVAL; 1660 } 1661 1662 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]); 1663 /* Max logical block */ 1664 put_unaligned_be32(512, &buf[4]); /* Block length */ 1665 return 8; 1666} 1667 1668 1669static int do_read_header(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1670{ 1671 struct fsg_lun *curlun = fsg->curlun; 1672 int msf = fsg->cmnd[1] & 0x02; 1673 u32 lba = get_unaligned_be32(&fsg->cmnd[2]); 1674 u8 *buf = (u8 *) bh->buf; 1675 1676 if ((fsg->cmnd[1] & ~0x02) != 0) { /* Mask away MSF */ 1677 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1678 return -EINVAL; 1679 } 1680 if (lba >= curlun->num_sectors) { 1681 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE; 1682 return -EINVAL; 1683 } 1684 1685 memset(buf, 0, 8); 1686 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */ 1687 store_cdrom_address(&buf[4], msf, lba); 1688 return 8; 1689} 1690 1691 1692static int do_read_toc(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1693{ 1694 struct fsg_lun *curlun = fsg->curlun; 1695 int msf = fsg->cmnd[1] & 0x02; 1696 int start_track = fsg->cmnd[6]; 1697 u8 *buf = (u8 *) bh->buf; 1698 1699 if ((fsg->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */ 1700 start_track > 1) { 1701 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1702 return -EINVAL; 1703 } 1704 1705 memset(buf, 0, 20); 1706 buf[1] = (20-2); /* TOC data length */ 1707 buf[2] = 1; /* First track number */ 1708 buf[3] = 1; /* Last track number */ 1709 buf[5] = 0x16; /* Data track, copying allowed */ 1710 buf[6] = 0x01; /* Only track is number 1 */ 1711 store_cdrom_address(&buf[8], msf, 0); 1712 1713 buf[13] = 0x16; /* Lead-out track is data */ 1714 buf[14] = 0xAA; /* Lead-out track number */ 1715 store_cdrom_address(&buf[16], msf, curlun->num_sectors); 1716 return 20; 1717} 1718 1719 1720static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1721{ 1722 struct fsg_lun *curlun = fsg->curlun; 1723 int mscmnd = fsg->cmnd[0]; 1724 u8 *buf = (u8 *) bh->buf; 1725 u8 *buf0 = buf; 1726 int pc, page_code; 1727 int changeable_values, all_pages; 1728 int valid_page = 0; 1729 int len, limit; 1730 1731 if ((fsg->cmnd[1] & ~0x08) != 0) { // Mask away DBD 1732 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1733 return -EINVAL; 1734 } 1735 pc = fsg->cmnd[2] >> 6; 1736 page_code = fsg->cmnd[2] & 0x3f; 1737 if (pc == 3) { 1738 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED; 1739 return -EINVAL; 1740 } 1741 changeable_values = (pc == 1); 1742 all_pages = (page_code == 0x3f); 1743 1744 /* Write the mode parameter header. Fixed values are: default 1745 * medium type, no cache control (DPOFUA), and no block descriptors. 1746 * The only variable value is the WriteProtect bit. We will fill in 1747 * the mode data length later. */ 1748 memset(buf, 0, 8); 1749 if (mscmnd == SC_MODE_SENSE_6) { 1750 buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA 1751 buf += 4; 1752 limit = 255; 1753 } else { // SC_MODE_SENSE_10 1754 buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA 1755 buf += 8; 1756 limit = 65535; // Should really be mod_data.buflen 1757 } 1758 1759 /* No block descriptors */ 1760 1761 /* The mode pages, in numerical order. The only page we support 1762 * is the Caching page. */ 1763 if (page_code == 0x08 || all_pages) { 1764 valid_page = 1; 1765 buf[0] = 0x08; // Page code 1766 buf[1] = 10; // Page length 1767 memset(buf+2, 0, 10); // None of the fields are changeable 1768 1769 if (!changeable_values) { 1770 buf[2] = 0x04; // Write cache enable, 1771 // Read cache not disabled 1772 // No cache retention priorities 1773 put_unaligned_be16(0xffff, &buf[4]); 1774 /* Don't disable prefetch */ 1775 /* Minimum prefetch = 0 */ 1776 put_unaligned_be16(0xffff, &buf[8]); 1777 /* Maximum prefetch */ 1778 put_unaligned_be16(0xffff, &buf[10]); 1779 /* Maximum prefetch ceiling */ 1780 } 1781 buf += 12; 1782 } 1783 1784 /* Check that a valid page was requested and the mode data length 1785 * isn't too long. */ 1786 len = buf - buf0; 1787 if (!valid_page || len > limit) { 1788 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1789 return -EINVAL; 1790 } 1791 1792 /* Store the mode data length */ 1793 if (mscmnd == SC_MODE_SENSE_6) 1794 buf0[0] = len - 1; 1795 else 1796 put_unaligned_be16(len - 2, buf0); 1797 return len; 1798} 1799 1800 1801static int do_start_stop(struct fsg_dev *fsg) 1802{ 1803 struct fsg_lun *curlun = fsg->curlun; 1804 int loej, start; 1805 1806 if (!mod_data.removable) { 1807 curlun->sense_data = SS_INVALID_COMMAND; 1808 return -EINVAL; 1809 } 1810 1811 // int immed = fsg->cmnd[1] & 0x01; 1812 loej = fsg->cmnd[4] & 0x02; 1813 start = fsg->cmnd[4] & 0x01; 1814 1815#ifdef CONFIG_USB_FILE_STORAGE_TEST 1816 if ((fsg->cmnd[1] & ~0x01) != 0 || // Mask away Immed 1817 (fsg->cmnd[4] & ~0x03) != 0) { // Mask LoEj, Start 1818 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1819 return -EINVAL; 1820 } 1821 1822 if (!start) { 1823 1824 /* Are we allowed to unload the media? */ 1825 if (curlun->prevent_medium_removal) { 1826 LDBG(curlun, "unload attempt prevented\n"); 1827 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED; 1828 return -EINVAL; 1829 } 1830 if (loej) { // Simulate an unload/eject 1831 up_read(&fsg->filesem); 1832 down_write(&fsg->filesem); 1833 fsg_lun_close(curlun); 1834 up_write(&fsg->filesem); 1835 down_read(&fsg->filesem); 1836 } 1837 } else { 1838 1839 /* Our emulation doesn't support mounting; the medium is 1840 * available for use as soon as it is loaded. */ 1841 if (!fsg_lun_is_open(curlun)) { 1842 curlun->sense_data = SS_MEDIUM_NOT_PRESENT; 1843 return -EINVAL; 1844 } 1845 } 1846#endif 1847 return 0; 1848} 1849 1850 1851static int do_prevent_allow(struct fsg_dev *fsg) 1852{ 1853 struct fsg_lun *curlun = fsg->curlun; 1854 int prevent; 1855 1856 if (!mod_data.removable) { 1857 curlun->sense_data = SS_INVALID_COMMAND; 1858 return -EINVAL; 1859 } 1860 1861 prevent = fsg->cmnd[4] & 0x01; 1862 if ((fsg->cmnd[4] & ~0x01) != 0) { // Mask away Prevent 1863 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 1864 return -EINVAL; 1865 } 1866 1867 if (curlun->prevent_medium_removal && !prevent) 1868 fsg_lun_fsync_sub(curlun); 1869 curlun->prevent_medium_removal = prevent; 1870 return 0; 1871} 1872 1873 1874static int do_read_format_capacities(struct fsg_dev *fsg, 1875 struct fsg_buffhd *bh) 1876{ 1877 struct fsg_lun *curlun = fsg->curlun; 1878 u8 *buf = (u8 *) bh->buf; 1879 1880 buf[0] = buf[1] = buf[2] = 0; 1881 buf[3] = 8; // Only the Current/Maximum Capacity Descriptor 1882 buf += 4; 1883 1884 put_unaligned_be32(curlun->num_sectors, &buf[0]); 1885 /* Number of blocks */ 1886 put_unaligned_be32(512, &buf[4]); /* Block length */ 1887 buf[4] = 0x02; /* Current capacity */ 1888 return 12; 1889} 1890 1891 1892static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh) 1893{ 1894 struct fsg_lun *curlun = fsg->curlun; 1895 1896 /* We don't support MODE SELECT */ 1897 curlun->sense_data = SS_INVALID_COMMAND; 1898 return -EINVAL; 1899} 1900 1901 1902/*-------------------------------------------------------------------------*/ 1903 1904static int halt_bulk_in_endpoint(struct fsg_dev *fsg) 1905{ 1906 int rc; 1907 1908 rc = fsg_set_halt(fsg, fsg->bulk_in); 1909 if (rc == -EAGAIN) 1910 VDBG(fsg, "delayed bulk-in endpoint halt\n"); 1911 while (rc != 0) { 1912 if (rc != -EAGAIN) { 1913 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc); 1914 rc = 0; 1915 break; 1916 } 1917 1918 /* Wait for a short time and then try again */ 1919 if (msleep_interruptible(100) != 0) 1920 return -EINTR; 1921 rc = usb_ep_set_halt(fsg->bulk_in); 1922 } 1923 return rc; 1924} 1925 1926static int wedge_bulk_in_endpoint(struct fsg_dev *fsg) 1927{ 1928 int rc; 1929 1930 DBG(fsg, "bulk-in set wedge\n"); 1931 rc = usb_ep_set_wedge(fsg->bulk_in); 1932 if (rc == -EAGAIN) 1933 VDBG(fsg, "delayed bulk-in endpoint wedge\n"); 1934 while (rc != 0) { 1935 if (rc != -EAGAIN) { 1936 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc); 1937 rc = 0; 1938 break; 1939 } 1940 1941 /* Wait for a short time and then try again */ 1942 if (msleep_interruptible(100) != 0) 1943 return -EINTR; 1944 rc = usb_ep_set_wedge(fsg->bulk_in); 1945 } 1946 return rc; 1947} 1948 1949static int pad_with_zeros(struct fsg_dev *fsg) 1950{ 1951 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; 1952 u32 nkeep = bh->inreq->length; 1953 u32 nsend; 1954 int rc; 1955 1956 bh->state = BUF_STATE_EMPTY; // For the first iteration 1957 fsg->usb_amount_left = nkeep + fsg->residue; 1958 while (fsg->usb_amount_left > 0) { 1959 1960 /* Wait for the next buffer to be free */ 1961 while (bh->state != BUF_STATE_EMPTY) { 1962 rc = sleep_thread(fsg); 1963 if (rc) 1964 return rc; 1965 } 1966 1967 nsend = min(fsg->usb_amount_left, (u32) mod_data.buflen); 1968 memset(bh->buf + nkeep, 0, nsend - nkeep); 1969 bh->inreq->length = nsend; 1970 bh->inreq->zero = 0; 1971 start_transfer(fsg, fsg->bulk_in, bh->inreq, 1972 &bh->inreq_busy, &bh->state); 1973 bh = fsg->next_buffhd_to_fill = bh->next; 1974 fsg->usb_amount_left -= nsend; 1975 nkeep = 0; 1976 } 1977 return 0; 1978} 1979 1980static int throw_away_data(struct fsg_dev *fsg) 1981{ 1982 struct fsg_buffhd *bh; 1983 u32 amount; 1984 int rc; 1985 1986 while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY || 1987 fsg->usb_amount_left > 0) { 1988 1989 /* Throw away the data in a filled buffer */ 1990 if (bh->state == BUF_STATE_FULL) { 1991 smp_rmb(); 1992 bh->state = BUF_STATE_EMPTY; 1993 fsg->next_buffhd_to_drain = bh->next; 1994 1995 /* A short packet or an error ends everything */ 1996 if (bh->outreq->actual != bh->outreq->length || 1997 bh->outreq->status != 0) { 1998 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); 1999 return -EINTR; 2000 } 2001 continue; 2002 } 2003 2004 /* Try to submit another request if we need one */ 2005 bh = fsg->next_buffhd_to_fill; 2006 if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) { 2007 amount = min(fsg->usb_amount_left, 2008 (u32) mod_data.buflen); 2009 2010 /* amount is always divisible by 512, hence by 2011 * the bulk-out maxpacket size */ 2012 bh->outreq->length = bh->bulk_out_intended_length = 2013 amount; 2014 bh->outreq->short_not_ok = 1; 2015 start_transfer(fsg, fsg->bulk_out, bh->outreq, 2016 &bh->outreq_busy, &bh->state); 2017 fsg->next_buffhd_to_fill = bh->next; 2018 fsg->usb_amount_left -= amount; 2019 continue; 2020 } 2021 2022 /* Otherwise wait for something to happen */ 2023 rc = sleep_thread(fsg); 2024 if (rc) 2025 return rc; 2026 } 2027 return 0; 2028} 2029 2030 2031static int finish_reply(struct fsg_dev *fsg) 2032{ 2033 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill; 2034 int rc = 0; 2035 2036 switch (fsg->data_dir) { 2037 case DATA_DIR_NONE: 2038 break; // Nothing to send 2039 2040 /* If we don't know whether the host wants to read or write, 2041 * this must be CB or CBI with an unknown command. We mustn't 2042 * try to send or receive any data. So stall both bulk pipes 2043 * if we can and wait for a reset. */ 2044 case DATA_DIR_UNKNOWN: 2045 if (mod_data.can_stall) { 2046 fsg_set_halt(fsg, fsg->bulk_out); 2047 rc = halt_bulk_in_endpoint(fsg); 2048 } 2049 break; 2050 2051 /* All but the last buffer of data must have already been sent */ 2052 case DATA_DIR_TO_HOST: 2053 if (fsg->data_size == 0) 2054 ; // Nothing to send 2055 2056 /* If there's no residue, simply send the last buffer */ 2057 else if (fsg->residue == 0) { 2058 bh->inreq->zero = 0; 2059 start_transfer(fsg, fsg->bulk_in, bh->inreq, 2060 &bh->inreq_busy, &bh->state); 2061 fsg->next_buffhd_to_fill = bh->next; 2062 } 2063 2064 /* There is a residue. For CB and CBI, simply mark the end 2065 * of the data with a short packet. However, if we are 2066 * allowed to stall, there was no data at all (residue == 2067 * data_size), and the command failed (invalid LUN or 2068 * sense data is set), then halt the bulk-in endpoint 2069 * instead. */ 2070 else if (!transport_is_bbb()) { 2071 if (mod_data.can_stall && 2072 fsg->residue == fsg->data_size && 2073 (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) { 2074 bh->state = BUF_STATE_EMPTY; 2075 rc = halt_bulk_in_endpoint(fsg); 2076 } else { 2077 bh->inreq->zero = 1; 2078 start_transfer(fsg, fsg->bulk_in, bh->inreq, 2079 &bh->inreq_busy, &bh->state); 2080 fsg->next_buffhd_to_fill = bh->next; 2081 } 2082 } 2083 2084 /* For Bulk-only, if we're allowed to stall then send the 2085 * short packet and halt the bulk-in endpoint. If we can't 2086 * stall, pad out the remaining data with 0's. */ 2087 else { 2088 if (mod_data.can_stall) { 2089 bh->inreq->zero = 1; 2090 start_transfer(fsg, fsg->bulk_in, bh->inreq, 2091 &bh->inreq_busy, &bh->state); 2092 fsg->next_buffhd_to_fill = bh->next; 2093 rc = halt_bulk_in_endpoint(fsg); 2094 } else 2095 rc = pad_with_zeros(fsg); 2096 } 2097 break; 2098 2099 /* We have processed all we want from the data the host has sent. 2100 * There may still be outstanding bulk-out requests. */ 2101 case DATA_DIR_FROM_HOST: 2102 if (fsg->residue == 0) 2103 ; // Nothing to receive 2104 2105 /* Did the host stop sending unexpectedly early? */ 2106 else if (fsg->short_packet_received) { 2107 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); 2108 rc = -EINTR; 2109 } 2110 2111 /* We haven't processed all the incoming data. Even though 2112 * we may be allowed to stall, doing so would cause a race. 2113 * The controller may already have ACK'ed all the remaining 2114 * bulk-out packets, in which case the host wouldn't see a 2115 * STALL. Not realizing the endpoint was halted, it wouldn't 2116 * clear the halt -- leading to problems later on. */ 2117#if 0 2118 else if (mod_data.can_stall) { 2119 fsg_set_halt(fsg, fsg->bulk_out); 2120 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT); 2121 rc = -EINTR; 2122 } 2123#endif 2124 2125 /* We can't stall. Read in the excess data and throw it 2126 * all away. */ 2127 else 2128 rc = throw_away_data(fsg); 2129 break; 2130 } 2131 return rc; 2132} 2133 2134 2135static int send_status(struct fsg_dev *fsg) 2136{ 2137 struct fsg_lun *curlun = fsg->curlun; 2138 struct fsg_buffhd *bh; 2139 int rc; 2140 u8 status = USB_STATUS_PASS; 2141 u32 sd, sdinfo = 0; 2142 2143 /* Wait for the next buffer to become available */ 2144 bh = fsg->next_buffhd_to_fill; 2145 while (bh->state != BUF_STATE_EMPTY) { 2146 rc = sleep_thread(fsg); 2147 if (rc) 2148 return rc; 2149 } 2150 2151 if (curlun) { 2152 sd = curlun->sense_data; 2153 sdinfo = curlun->sense_data_info; 2154 } else if (fsg->bad_lun_okay) 2155 sd = SS_NO_SENSE; 2156 else 2157 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED; 2158 2159 if (fsg->phase_error) { 2160 DBG(fsg, "sending phase-error status\n"); 2161 status = USB_STATUS_PHASE_ERROR; 2162 sd = SS_INVALID_COMMAND; 2163 } else if (sd != SS_NO_SENSE) { 2164 DBG(fsg, "sending command-failure status\n"); 2165 status = USB_STATUS_FAIL; 2166 VDBG(fsg, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;" 2167 " info x%x\n", 2168 SK(sd), ASC(sd), ASCQ(sd), sdinfo); 2169 } 2170 2171 if (transport_is_bbb()) { 2172 struct bulk_cs_wrap *csw = bh->buf; 2173 2174 /* Store and send the Bulk-only CSW */ 2175 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG); 2176 csw->Tag = fsg->tag; 2177 csw->Residue = cpu_to_le32(fsg->residue); 2178 csw->Status = status; 2179 2180 bh->inreq->length = USB_BULK_CS_WRAP_LEN; 2181 bh->inreq->zero = 0; 2182 start_transfer(fsg, fsg->bulk_in, bh->inreq, 2183 &bh->inreq_busy, &bh->state); 2184 2185 } else if (mod_data.transport_type == USB_PR_CB) { 2186 2187 /* Control-Bulk transport has no status phase! */ 2188 return 0; 2189 2190 } else { // USB_PR_CBI 2191 struct interrupt_data *buf = bh->buf; 2192 2193 /* Store and send the Interrupt data. UFI sends the ASC 2194 * and ASCQ bytes. Everything else sends a Type (which 2195 * is always 0) and the status Value. */ 2196 if (mod_data.protocol_type == USB_SC_UFI) { 2197 buf->bType = ASC(sd); 2198 buf->bValue = ASCQ(sd); 2199 } else { 2200 buf->bType = 0; 2201 buf->bValue = status; 2202 } 2203 fsg->intreq->length = CBI_INTERRUPT_DATA_LEN; 2204 2205 fsg->intr_buffhd = bh; // Point to the right buffhd 2206 fsg->intreq->buf = bh->inreq->buf; 2207 fsg->intreq->context = bh; 2208 start_transfer(fsg, fsg->intr_in, fsg->intreq, 2209 &fsg->intreq_busy, &bh->state); 2210 } 2211 2212 fsg->next_buffhd_to_fill = bh->next; 2213 return 0; 2214} 2215 2216 2217/*-------------------------------------------------------------------------*/ 2218 2219/* Check whether the command is properly formed and whether its data size 2220 * and direction agree with the values we already have. */ 2221static int check_command(struct fsg_dev *fsg, int cmnd_size, 2222 enum data_direction data_dir, unsigned int mask, 2223 int needs_medium, const char *name) 2224{ 2225 int i; 2226 int lun = fsg->cmnd[1] >> 5; 2227 static const char dirletter[4] = {'u', 'o', 'i', 'n'}; 2228 char hdlen[20]; 2229 struct fsg_lun *curlun; 2230 2231 /* Adjust the expected cmnd_size for protocol encapsulation padding. 2232 * Transparent SCSI doesn't pad. */ 2233 if (protocol_is_scsi()) 2234 ; 2235 2236 /* There's some disagreement as to whether RBC pads commands or not. 2237 * We'll play it safe and accept either form. */ 2238 else if (mod_data.protocol_type == USB_SC_RBC) { 2239 if (fsg->cmnd_size == 12) 2240 cmnd_size = 12; 2241 2242 /* All the other protocols pad to 12 bytes */ 2243 } else 2244 cmnd_size = 12; 2245 2246 hdlen[0] = 0; 2247 if (fsg->data_dir != DATA_DIR_UNKNOWN) 2248 sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir], 2249 fsg->data_size); 2250 VDBG(fsg, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n", 2251 name, cmnd_size, dirletter[(int) data_dir], 2252 fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen); 2253 2254 /* We can't reply at all until we know the correct data direction 2255 * and size. */ 2256 if (fsg->data_size_from_cmnd == 0) 2257 data_dir = DATA_DIR_NONE; 2258 if (fsg->data_dir == DATA_DIR_UNKNOWN) { // CB or CBI 2259 fsg->data_dir = data_dir; 2260 fsg->data_size = fsg->data_size_from_cmnd; 2261 2262 } else { // Bulk-only 2263 if (fsg->data_size < fsg->data_size_from_cmnd) { 2264 2265 /* Host data size < Device data size is a phase error. 2266 * Carry out the command, but only transfer as much 2267 * as we are allowed. */ 2268 fsg->data_size_from_cmnd = fsg->data_size; 2269 fsg->phase_error = 1; 2270 } 2271 } 2272 fsg->residue = fsg->usb_amount_left = fsg->data_size; 2273 2274 /* Conflicting data directions is a phase error */ 2275 if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) { 2276 fsg->phase_error = 1; 2277 return -EINVAL; 2278 } 2279 2280 /* Verify the length of the command itself */ 2281 if (cmnd_size != fsg->cmnd_size) { 2282 2283 /* Special case workaround: There are plenty of buggy SCSI 2284 * implementations. Many have issues with cbw->Length 2285 * field passing a wrong command size. For those cases we 2286 * always try to work around the problem by using the length 2287 * sent by the host side provided it is at least as large 2288 * as the correct command length. 2289 * Examples of such cases would be MS-Windows, which issues 2290 * REQUEST SENSE with cbw->Length == 12 where it should 2291 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and 2292 * REQUEST SENSE with cbw->Length == 10 where it should 2293 * be 6 as well. 2294 */ 2295 if (cmnd_size <= fsg->cmnd_size) { 2296 DBG(fsg, "%s is buggy! Expected length %d " 2297 "but we got %d\n", name, 2298 cmnd_size, fsg->cmnd_size); 2299 cmnd_size = fsg->cmnd_size; 2300 } else { 2301 fsg->phase_error = 1; 2302 return -EINVAL; 2303 } 2304 } 2305 2306 /* Check that the LUN values are consistent */ 2307 if (transport_is_bbb()) { 2308 if (fsg->lun != lun) 2309 DBG(fsg, "using LUN %d from CBW, " 2310 "not LUN %d from CDB\n", 2311 fsg->lun, lun); 2312 } else 2313 fsg->lun = lun; // Use LUN from the command 2314 2315 /* Check the LUN */ 2316 if (fsg->lun >= 0 && fsg->lun < fsg->nluns) { 2317 fsg->curlun = curlun = &fsg->luns[fsg->lun]; 2318 if (fsg->cmnd[0] != SC_REQUEST_SENSE) { 2319 curlun->sense_data = SS_NO_SENSE; 2320 curlun->sense_data_info = 0; 2321 curlun->info_valid = 0; 2322 } 2323 } else { 2324 fsg->curlun = curlun = NULL; 2325 fsg->bad_lun_okay = 0; 2326 2327 /* INQUIRY and REQUEST SENSE commands are explicitly allowed 2328 * to use unsupported LUNs; all others may not. */ 2329 if (fsg->cmnd[0] != SC_INQUIRY && 2330 fsg->cmnd[0] != SC_REQUEST_SENSE) { 2331 DBG(fsg, "unsupported LUN %d\n", fsg->lun); 2332 return -EINVAL; 2333 } 2334 } 2335 2336 /* If a unit attention condition exists, only INQUIRY and 2337 * REQUEST SENSE commands are allowed; anything else must fail. */ 2338 if (curlun && curlun->unit_attention_data != SS_NO_SENSE && 2339 fsg->cmnd[0] != SC_INQUIRY && 2340 fsg->cmnd[0] != SC_REQUEST_SENSE) { 2341 curlun->sense_data = curlun->unit_attention_data; 2342 curlun->unit_attention_data = SS_NO_SENSE; 2343 return -EINVAL; 2344 } 2345 2346 /* Check that only command bytes listed in the mask are non-zero */ 2347 fsg->cmnd[1] &= 0x1f; // Mask away the LUN 2348 for (i = 1; i < cmnd_size; ++i) { 2349 if (fsg->cmnd[i] && !(mask & (1 << i))) { 2350 if (curlun) 2351 curlun->sense_data = SS_INVALID_FIELD_IN_CDB; 2352 return -EINVAL; 2353 } 2354 } 2355 2356 /* If the medium isn't mounted and the command needs to access 2357 * it, return an error. */ 2358 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) { 2359 curlun->sense_data = SS_MEDIUM_NOT_PRESENT; 2360 return -EINVAL; 2361 } 2362 2363 return 0; 2364} 2365 2366 2367static int do_scsi_command(struct fsg_dev *fsg) 2368{ 2369 struct fsg_buffhd *bh; 2370 int rc; 2371 int reply = -EINVAL; 2372 int i; 2373 static char unknown[16]; 2374 2375 dump_cdb(fsg); 2376 2377 /* Wait for the next buffer to become available for data or status */ 2378 bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill; 2379 while (bh->state != BUF_STATE_EMPTY) { 2380 rc = sleep_thread(fsg); 2381 if (rc) 2382 return rc; 2383 } 2384 fsg->phase_error = 0; 2385 fsg->short_packet_received = 0; 2386 2387 down_read(&fsg->filesem); // We're using the backing file 2388 switch (fsg->cmnd[0]) { 2389 2390 case SC_INQUIRY: 2391 fsg->data_size_from_cmnd = fsg->cmnd[4]; 2392 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, 2393 (1<<4), 0, 2394 "INQUIRY")) == 0) 2395 reply = do_inquiry(fsg, bh); 2396 break; 2397 2398 case SC_MODE_SELECT_6: 2399 fsg->data_size_from_cmnd = fsg->cmnd[4]; 2400 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, 2401 (1<<1) | (1<<4), 0, 2402 "MODE SELECT(6)")) == 0) 2403 reply = do_mode_select(fsg, bh); 2404 break; 2405 2406 case SC_MODE_SELECT_10: 2407 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); 2408 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, 2409 (1<<1) | (3<<7), 0, 2410 "MODE SELECT(10)")) == 0) 2411 reply = do_mode_select(fsg, bh); 2412 break; 2413 2414 case SC_MODE_SENSE_6: 2415 fsg->data_size_from_cmnd = fsg->cmnd[4]; 2416 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, 2417 (1<<1) | (1<<2) | (1<<4), 0, 2418 "MODE SENSE(6)")) == 0) 2419 reply = do_mode_sense(fsg, bh); 2420 break; 2421 2422 case SC_MODE_SENSE_10: 2423 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); 2424 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2425 (1<<1) | (1<<2) | (3<<7), 0, 2426 "MODE SENSE(10)")) == 0) 2427 reply = do_mode_sense(fsg, bh); 2428 break; 2429 2430 case SC_PREVENT_ALLOW_MEDIUM_REMOVAL: 2431 fsg->data_size_from_cmnd = 0; 2432 if ((reply = check_command(fsg, 6, DATA_DIR_NONE, 2433 (1<<4), 0, 2434 "PREVENT-ALLOW MEDIUM REMOVAL")) == 0) 2435 reply = do_prevent_allow(fsg); 2436 break; 2437 2438 case SC_READ_6: 2439 i = fsg->cmnd[4]; 2440 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; 2441 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, 2442 (7<<1) | (1<<4), 1, 2443 "READ(6)")) == 0) 2444 reply = do_read(fsg); 2445 break; 2446 2447 case SC_READ_10: 2448 fsg->data_size_from_cmnd = 2449 get_unaligned_be16(&fsg->cmnd[7]) << 9; 2450 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2451 (1<<1) | (0xf<<2) | (3<<7), 1, 2452 "READ(10)")) == 0) 2453 reply = do_read(fsg); 2454 break; 2455 2456 case SC_READ_12: 2457 fsg->data_size_from_cmnd = 2458 get_unaligned_be32(&fsg->cmnd[6]) << 9; 2459 if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST, 2460 (1<<1) | (0xf<<2) | (0xf<<6), 1, 2461 "READ(12)")) == 0) 2462 reply = do_read(fsg); 2463 break; 2464 2465 case SC_READ_CAPACITY: 2466 fsg->data_size_from_cmnd = 8; 2467 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2468 (0xf<<2) | (1<<8), 1, 2469 "READ CAPACITY")) == 0) 2470 reply = do_read_capacity(fsg, bh); 2471 break; 2472 2473 case SC_READ_HEADER: 2474 if (!mod_data.cdrom) 2475 goto unknown_cmnd; 2476 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); 2477 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2478 (3<<7) | (0x1f<<1), 1, 2479 "READ HEADER")) == 0) 2480 reply = do_read_header(fsg, bh); 2481 break; 2482 2483 case SC_READ_TOC: 2484 if (!mod_data.cdrom) 2485 goto unknown_cmnd; 2486 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); 2487 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2488 (7<<6) | (1<<1), 1, 2489 "READ TOC")) == 0) 2490 reply = do_read_toc(fsg, bh); 2491 break; 2492 2493 case SC_READ_FORMAT_CAPACITIES: 2494 fsg->data_size_from_cmnd = get_unaligned_be16(&fsg->cmnd[7]); 2495 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST, 2496 (3<<7), 1, 2497 "READ FORMAT CAPACITIES")) == 0) 2498 reply = do_read_format_capacities(fsg, bh); 2499 break; 2500 2501 case SC_REQUEST_SENSE: 2502 fsg->data_size_from_cmnd = fsg->cmnd[4]; 2503 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST, 2504 (1<<4), 0, 2505 "REQUEST SENSE")) == 0) 2506 reply = do_request_sense(fsg, bh); 2507 break; 2508 2509 case SC_START_STOP_UNIT: 2510 fsg->data_size_from_cmnd = 0; 2511 if ((reply = check_command(fsg, 6, DATA_DIR_NONE, 2512 (1<<1) | (1<<4), 0, 2513 "START-STOP UNIT")) == 0) 2514 reply = do_start_stop(fsg); 2515 break; 2516 2517 case SC_SYNCHRONIZE_CACHE: 2518 fsg->data_size_from_cmnd = 0; 2519 if ((reply = check_command(fsg, 10, DATA_DIR_NONE, 2520 (0xf<<2) | (3<<7), 1, 2521 "SYNCHRONIZE CACHE")) == 0) 2522 reply = do_synchronize_cache(fsg); 2523 break; 2524 2525 case SC_TEST_UNIT_READY: 2526 fsg->data_size_from_cmnd = 0; 2527 reply = check_command(fsg, 6, DATA_DIR_NONE, 2528 0, 1, 2529 "TEST UNIT READY"); 2530 break; 2531 2532 /* Although optional, this command is used by MS-Windows. We 2533 * support a minimal version: BytChk must be 0. */ 2534 case SC_VERIFY: 2535 fsg->data_size_from_cmnd = 0; 2536 if ((reply = check_command(fsg, 10, DATA_DIR_NONE, 2537 (1<<1) | (0xf<<2) | (3<<7), 1, 2538 "VERIFY")) == 0) 2539 reply = do_verify(fsg); 2540 break; 2541 2542 case SC_WRITE_6: 2543 i = fsg->cmnd[4]; 2544 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9; 2545 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST, 2546 (7<<1) | (1<<4), 1, 2547 "WRITE(6)")) == 0) 2548 reply = do_write(fsg); 2549 break; 2550 2551 case SC_WRITE_10: 2552 fsg->data_size_from_cmnd = 2553 get_unaligned_be16(&fsg->cmnd[7]) << 9; 2554 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST, 2555 (1<<1) | (0xf<<2) | (3<<7), 1, 2556 "WRITE(10)")) == 0) 2557 reply = do_write(fsg); 2558 break; 2559 2560 case SC_WRITE_12: 2561 fsg->data_size_from_cmnd = 2562 get_unaligned_be32(&fsg->cmnd[6]) << 9; 2563 if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST, 2564 (1<<1) | (0xf<<2) | (0xf<<6), 1, 2565 "WRITE(12)")) == 0) 2566 reply = do_write(fsg); 2567 break; 2568 2569 /* Some mandatory commands that we recognize but don't implement. 2570 * They don't mean much in this setting. It's left as an exercise 2571 * for anyone interested to implement RESERVE and RELEASE in terms 2572 * of Posix locks. */ 2573 case SC_FORMAT_UNIT: 2574 case SC_RELEASE: 2575 case SC_RESERVE: 2576 case SC_SEND_DIAGNOSTIC: 2577 // Fall through 2578 2579 default: 2580 unknown_cmnd: 2581 fsg->data_size_from_cmnd = 0; 2582 sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]); 2583 if ((reply = check_command(fsg, fsg->cmnd_size, 2584 DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) { 2585 fsg->curlun->sense_data = SS_INVALID_COMMAND; 2586 reply = -EINVAL; 2587 } 2588 break; 2589 } 2590 up_read(&fsg->filesem); 2591 2592 if (reply == -EINTR || signal_pending(current)) 2593 return -EINTR; 2594 2595 /* Set up the single reply buffer for finish_reply() */ 2596 if (reply == -EINVAL) 2597 reply = 0; // Error reply length 2598 if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) { 2599 reply = min((u32) reply, fsg->data_size_from_cmnd); 2600 bh->inreq->length = reply; 2601 bh->state = BUF_STATE_FULL; 2602 fsg->residue -= reply; 2603 } // Otherwise it's already set 2604 2605 return 0; 2606} 2607 2608 2609/*-------------------------------------------------------------------------*/ 2610 2611static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh) 2612{ 2613 struct usb_request *req = bh->outreq; 2614 struct fsg_bulk_cb_wrap *cbw = req->buf; 2615 2616 /* Was this a real packet? Should it be ignored? */ 2617 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags)) 2618 return -EINVAL; 2619 2620 /* Is the CBW valid? */ 2621 if (req->actual != USB_BULK_CB_WRAP_LEN || 2622 cbw->Signature != cpu_to_le32( 2623 USB_BULK_CB_SIG)) { 2624 DBG(fsg, "invalid CBW: len %u sig 0x%x\n", 2625 req->actual, 2626 le32_to_cpu(cbw->Signature)); 2627 2628 /* The Bulk-only spec says we MUST stall the IN endpoint 2629 * (6.6.1), so it's unavoidable. It also says we must 2630 * retain this state until the next reset, but there's 2631 * no way to tell the controller driver it should ignore 2632 * Clear-Feature(HALT) requests. 2633 * 2634 * We aren't required to halt the OUT endpoint; instead 2635 * we can simply accept and discard any data received 2636 * until the next reset. */ 2637 wedge_bulk_in_endpoint(fsg); 2638 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags); 2639 return -EINVAL; 2640 } 2641 2642 /* Is the CBW meaningful? */ 2643 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG || 2644 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) { 2645 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, " 2646 "cmdlen %u\n", 2647 cbw->Lun, cbw->Flags, cbw->Length); 2648 2649 /* We can do anything we want here, so let's stall the 2650 * bulk pipes if we are allowed to. */ 2651 if (mod_data.can_stall) { 2652 fsg_set_halt(fsg, fsg->bulk_out); 2653 halt_bulk_in_endpoint(fsg); 2654 } 2655 return -EINVAL; 2656 } 2657 2658 /* Save the command for later */ 2659 fsg->cmnd_size = cbw->Length; 2660 memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size); 2661 if (cbw->Flags & USB_BULK_IN_FLAG) 2662 fsg->data_dir = DATA_DIR_TO_HOST; 2663 else 2664 fsg->data_dir = DATA_DIR_FROM_HOST; 2665 fsg->data_size = le32_to_cpu(cbw->DataTransferLength); 2666 if (fsg->data_size == 0) 2667 fsg->data_dir = DATA_DIR_NONE; 2668 fsg->lun = cbw->Lun; 2669 fsg->tag = cbw->Tag; 2670 return 0; 2671} 2672 2673 2674static int get_next_command(struct fsg_dev *fsg) 2675{ 2676 struct fsg_buffhd *bh; 2677 int rc = 0; 2678 2679 if (transport_is_bbb()) { 2680 2681 /* Wait for the next buffer to become available */ 2682 bh = fsg->next_buffhd_to_fill; 2683 while (bh->state != BUF_STATE_EMPTY) { 2684 rc = sleep_thread(fsg); 2685 if (rc) 2686 return rc; 2687 } 2688 2689 /* Queue a request to read a Bulk-only CBW */ 2690 set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN); 2691 bh->outreq->short_not_ok = 1; 2692 start_transfer(fsg, fsg->bulk_out, bh->outreq, 2693 &bh->outreq_busy, &bh->state); 2694 2695 /* We will drain the buffer in software, which means we 2696 * can reuse it for the next filling. No need to advance 2697 * next_buffhd_to_fill. */ 2698 2699 /* Wait for the CBW to arrive */ 2700 while (bh->state != BUF_STATE_FULL) { 2701 rc = sleep_thread(fsg); 2702 if (rc) 2703 return rc; 2704 } 2705 smp_rmb(); 2706 rc = received_cbw(fsg, bh); 2707 bh->state = BUF_STATE_EMPTY; 2708 2709 } else { // USB_PR_CB or USB_PR_CBI 2710 2711 /* Wait for the next command to arrive */ 2712 while (fsg->cbbuf_cmnd_size == 0) { 2713 rc = sleep_thread(fsg); 2714 if (rc) 2715 return rc; 2716 } 2717 2718 /* Is the previous status interrupt request still busy? 2719 * The host is allowed to skip reading the status, 2720 * so we must cancel it. */ 2721 if (fsg->intreq_busy) 2722 usb_ep_dequeue(fsg->intr_in, fsg->intreq); 2723 2724 /* Copy the command and mark the buffer empty */ 2725 fsg->data_dir = DATA_DIR_UNKNOWN; 2726 spin_lock_irq(&fsg->lock); 2727 fsg->cmnd_size = fsg->cbbuf_cmnd_size; 2728 memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size); 2729 fsg->cbbuf_cmnd_size = 0; 2730 spin_unlock_irq(&fsg->lock); 2731 } 2732 return rc; 2733} 2734 2735 2736/*-------------------------------------------------------------------------*/ 2737 2738static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep, 2739 const struct usb_endpoint_descriptor *d) 2740{ 2741 int rc; 2742 2743 ep->driver_data = fsg; 2744 rc = usb_ep_enable(ep, d); 2745 if (rc) 2746 ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc); 2747 return rc; 2748} 2749 2750static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep, 2751 struct usb_request **preq) 2752{ 2753 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC); 2754 if (*preq) 2755 return 0; 2756 ERROR(fsg, "can't allocate request for %s\n", ep->name); 2757 return -ENOMEM; 2758} 2759 2760/* 2761 * Reset interface setting and re-init endpoint state (toggle etc). 2762 * Call with altsetting < 0 to disable the interface. The only other 2763 * available altsetting is 0, which enables the interface. 2764 */ 2765static int do_set_interface(struct fsg_dev *fsg, int altsetting) 2766{ 2767 int rc = 0; 2768 int i; 2769 const struct usb_endpoint_descriptor *d; 2770 2771 if (fsg->running) 2772 DBG(fsg, "reset interface\n"); 2773 2774reset: 2775 /* Deallocate the requests */ 2776 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 2777 struct fsg_buffhd *bh = &fsg->buffhds[i]; 2778 2779 if (bh->inreq) { 2780 usb_ep_free_request(fsg->bulk_in, bh->inreq); 2781 bh->inreq = NULL; 2782 } 2783 if (bh->outreq) { 2784 usb_ep_free_request(fsg->bulk_out, bh->outreq); 2785 bh->outreq = NULL; 2786 } 2787 } 2788 if (fsg->intreq) { 2789 usb_ep_free_request(fsg->intr_in, fsg->intreq); 2790 fsg->intreq = NULL; 2791 } 2792 2793 /* Disable the endpoints */ 2794 if (fsg->bulk_in_enabled) { 2795 usb_ep_disable(fsg->bulk_in); 2796 fsg->bulk_in_enabled = 0; 2797 } 2798 if (fsg->bulk_out_enabled) { 2799 usb_ep_disable(fsg->bulk_out); 2800 fsg->bulk_out_enabled = 0; 2801 } 2802 if (fsg->intr_in_enabled) { 2803 usb_ep_disable(fsg->intr_in); 2804 fsg->intr_in_enabled = 0; 2805 } 2806 2807 fsg->running = 0; 2808 if (altsetting < 0 || rc != 0) 2809 return rc; 2810 2811 DBG(fsg, "set interface %d\n", altsetting); 2812 2813 /* Enable the endpoints */ 2814 d = fsg_ep_desc(fsg->gadget, 2815 &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc); 2816 if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0) 2817 goto reset; 2818 fsg->bulk_in_enabled = 1; 2819 2820 d = fsg_ep_desc(fsg->gadget, 2821 &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc); 2822 if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0) 2823 goto reset; 2824 fsg->bulk_out_enabled = 1; 2825 fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize); 2826 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags); 2827 2828 if (transport_is_cbi()) { 2829 d = fsg_ep_desc(fsg->gadget, 2830 &fsg_fs_intr_in_desc, &fsg_hs_intr_in_desc); 2831 if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0) 2832 goto reset; 2833 fsg->intr_in_enabled = 1; 2834 } 2835 2836 /* Allocate the requests */ 2837 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 2838 struct fsg_buffhd *bh = &fsg->buffhds[i]; 2839 2840 if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0) 2841 goto reset; 2842 if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0) 2843 goto reset; 2844 bh->inreq->buf = bh->outreq->buf = bh->buf; 2845 bh->inreq->context = bh->outreq->context = bh; 2846 bh->inreq->complete = bulk_in_complete; 2847 bh->outreq->complete = bulk_out_complete; 2848 } 2849 if (transport_is_cbi()) { 2850 if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0) 2851 goto reset; 2852 fsg->intreq->complete = intr_in_complete; 2853 } 2854 2855 fsg->running = 1; 2856 for (i = 0; i < fsg->nluns; ++i) 2857 fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED; 2858 return rc; 2859} 2860 2861 2862/* 2863 * Change our operational configuration. This code must agree with the code 2864 * that returns config descriptors, and with interface altsetting code. 2865 * 2866 * It's also responsible for power management interactions. Some 2867 * configurations might not work with our current power sources. 2868 * For now we just assume the gadget is always self-powered. 2869 */ 2870static int do_set_config(struct fsg_dev *fsg, u8 new_config) 2871{ 2872 int rc = 0; 2873 2874 /* Disable the single interface */ 2875 if (fsg->config != 0) { 2876 DBG(fsg, "reset config\n"); 2877 fsg->config = 0; 2878 rc = do_set_interface(fsg, -1); 2879 } 2880 2881 /* Enable the interface */ 2882 if (new_config != 0) { 2883 fsg->config = new_config; 2884 if ((rc = do_set_interface(fsg, 0)) != 0) 2885 fsg->config = 0; // Reset on errors 2886 else { 2887 char *speed; 2888 2889 switch (fsg->gadget->speed) { 2890 case USB_SPEED_LOW: speed = "low"; break; 2891 case USB_SPEED_FULL: speed = "full"; break; 2892 case USB_SPEED_HIGH: speed = "high"; break; 2893 default: speed = "?"; break; 2894 } 2895 INFO(fsg, "%s speed config #%d\n", speed, fsg->config); 2896 } 2897 } 2898 return rc; 2899} 2900 2901 2902/*-------------------------------------------------------------------------*/ 2903 2904static void handle_exception(struct fsg_dev *fsg) 2905{ 2906 siginfo_t info; 2907 int sig; 2908 int i; 2909 int num_active; 2910 struct fsg_buffhd *bh; 2911 enum fsg_state old_state; 2912 u8 new_config; 2913 struct fsg_lun *curlun; 2914 unsigned int exception_req_tag; 2915 int rc; 2916 2917 /* Clear the existing signals. Anything but SIGUSR1 is converted 2918 * into a high-priority EXIT exception. */ 2919 for (;;) { 2920 sig = dequeue_signal_lock(current, ¤t->blocked, &info); 2921 if (!sig) 2922 break; 2923 if (sig != SIGUSR1) { 2924 if (fsg->state < FSG_STATE_EXIT) 2925 DBG(fsg, "Main thread exiting on signal\n"); 2926 raise_exception(fsg, FSG_STATE_EXIT); 2927 } 2928 } 2929 2930 /* Cancel all the pending transfers */ 2931 if (fsg->intreq_busy) 2932 usb_ep_dequeue(fsg->intr_in, fsg->intreq); 2933 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 2934 bh = &fsg->buffhds[i]; 2935 if (bh->inreq_busy) 2936 usb_ep_dequeue(fsg->bulk_in, bh->inreq); 2937 if (bh->outreq_busy) 2938 usb_ep_dequeue(fsg->bulk_out, bh->outreq); 2939 } 2940 2941 /* Wait until everything is idle */ 2942 for (;;) { 2943 num_active = fsg->intreq_busy; 2944 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 2945 bh = &fsg->buffhds[i]; 2946 num_active += bh->inreq_busy + bh->outreq_busy; 2947 } 2948 if (num_active == 0) 2949 break; 2950 if (sleep_thread(fsg)) 2951 return; 2952 } 2953 2954 /* Clear out the controller's fifos */ 2955 if (fsg->bulk_in_enabled) 2956 usb_ep_fifo_flush(fsg->bulk_in); 2957 if (fsg->bulk_out_enabled) 2958 usb_ep_fifo_flush(fsg->bulk_out); 2959 if (fsg->intr_in_enabled) 2960 usb_ep_fifo_flush(fsg->intr_in); 2961 2962 /* Reset the I/O buffer states and pointers, the SCSI 2963 * state, and the exception. Then invoke the handler. */ 2964 spin_lock_irq(&fsg->lock); 2965 2966 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 2967 bh = &fsg->buffhds[i]; 2968 bh->state = BUF_STATE_EMPTY; 2969 } 2970 fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain = 2971 &fsg->buffhds[0]; 2972 2973 exception_req_tag = fsg->exception_req_tag; 2974 new_config = fsg->new_config; 2975 old_state = fsg->state; 2976 2977 if (old_state == FSG_STATE_ABORT_BULK_OUT) 2978 fsg->state = FSG_STATE_STATUS_PHASE; 2979 else { 2980 for (i = 0; i < fsg->nluns; ++i) { 2981 curlun = &fsg->luns[i]; 2982 curlun->prevent_medium_removal = 0; 2983 curlun->sense_data = curlun->unit_attention_data = 2984 SS_NO_SENSE; 2985 curlun->sense_data_info = 0; 2986 curlun->info_valid = 0; 2987 } 2988 fsg->state = FSG_STATE_IDLE; 2989 } 2990 spin_unlock_irq(&fsg->lock); 2991 2992 /* Carry out any extra actions required for the exception */ 2993 switch (old_state) { 2994 default: 2995 break; 2996 2997 case FSG_STATE_ABORT_BULK_OUT: 2998 send_status(fsg); 2999 spin_lock_irq(&fsg->lock); 3000 if (fsg->state == FSG_STATE_STATUS_PHASE) 3001 fsg->state = FSG_STATE_IDLE; 3002 spin_unlock_irq(&fsg->lock); 3003 break; 3004 3005 case FSG_STATE_RESET: 3006 /* In case we were forced against our will to halt a 3007 * bulk endpoint, clear the halt now. (The SuperH UDC 3008 * requires this.) */ 3009 if (test_and_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags)) 3010 usb_ep_clear_halt(fsg->bulk_in); 3011 3012 if (transport_is_bbb()) { 3013 if (fsg->ep0_req_tag == exception_req_tag) 3014 ep0_queue(fsg); // Complete the status stage 3015 3016 } else if (transport_is_cbi()) 3017 send_status(fsg); // Status by interrupt pipe 3018 3019 /* Technically this should go here, but it would only be 3020 * a waste of time. Ditto for the INTERFACE_CHANGE and 3021 * CONFIG_CHANGE cases. */ 3022 // for (i = 0; i < fsg->nluns; ++i) 3023 // fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED; 3024 break; 3025 3026 case FSG_STATE_INTERFACE_CHANGE: 3027 rc = do_set_interface(fsg, 0); 3028 if (fsg->ep0_req_tag != exception_req_tag) 3029 break; 3030 if (rc != 0) // STALL on errors 3031 fsg_set_halt(fsg, fsg->ep0); 3032 else // Complete the status stage 3033 ep0_queue(fsg); 3034 break; 3035 3036 case FSG_STATE_CONFIG_CHANGE: 3037 rc = do_set_config(fsg, new_config); 3038 if (fsg->ep0_req_tag != exception_req_tag) 3039 break; 3040 if (rc != 0) // STALL on errors 3041 fsg_set_halt(fsg, fsg->ep0); 3042 else // Complete the status stage 3043 ep0_queue(fsg); 3044 break; 3045 3046 case FSG_STATE_DISCONNECT: 3047 for (i = 0; i < fsg->nluns; ++i) 3048 fsg_lun_fsync_sub(fsg->luns + i); 3049 do_set_config(fsg, 0); // Unconfigured state 3050 break; 3051 3052 case FSG_STATE_EXIT: 3053 case FSG_STATE_TERMINATED: 3054 do_set_config(fsg, 0); // Free resources 3055 spin_lock_irq(&fsg->lock); 3056 fsg->state = FSG_STATE_TERMINATED; // Stop the thread 3057 spin_unlock_irq(&fsg->lock); 3058 break; 3059 } 3060} 3061 3062 3063/*-------------------------------------------------------------------------*/ 3064 3065static int fsg_main_thread(void *fsg_) 3066{ 3067 struct fsg_dev *fsg = fsg_; 3068 3069 /* Allow the thread to be killed by a signal, but set the signal mask 3070 * to block everything but INT, TERM, KILL, and USR1. */ 3071 allow_signal(SIGINT); 3072 allow_signal(SIGTERM); 3073 allow_signal(SIGKILL); 3074 allow_signal(SIGUSR1); 3075 3076 /* Allow the thread to be frozen */ 3077 set_freezable(); 3078 3079 /* Arrange for userspace references to be interpreted as kernel 3080 * pointers. That way we can pass a kernel pointer to a routine 3081 * that expects a __user pointer and it will work okay. */ 3082 set_fs(get_ds()); 3083 3084 /* The main loop */ 3085 while (fsg->state != FSG_STATE_TERMINATED) { 3086 if (exception_in_progress(fsg) || signal_pending(current)) { 3087 handle_exception(fsg); 3088 continue; 3089 } 3090 3091 if (!fsg->running) { 3092 sleep_thread(fsg); 3093 continue; 3094 } 3095 3096 if (get_next_command(fsg)) 3097 continue; 3098 3099 spin_lock_irq(&fsg->lock); 3100 if (!exception_in_progress(fsg)) 3101 fsg->state = FSG_STATE_DATA_PHASE; 3102 spin_unlock_irq(&fsg->lock); 3103 3104 if (do_scsi_command(fsg) || finish_reply(fsg)) 3105 continue; 3106 3107 spin_lock_irq(&fsg->lock); 3108 if (!exception_in_progress(fsg)) 3109 fsg->state = FSG_STATE_STATUS_PHASE; 3110 spin_unlock_irq(&fsg->lock); 3111 3112 if (send_status(fsg)) 3113 continue; 3114 3115 spin_lock_irq(&fsg->lock); 3116 if (!exception_in_progress(fsg)) 3117 fsg->state = FSG_STATE_IDLE; 3118 spin_unlock_irq(&fsg->lock); 3119 } 3120 3121 spin_lock_irq(&fsg->lock); 3122 fsg->thread_task = NULL; 3123 spin_unlock_irq(&fsg->lock); 3124 3125 /* If we are exiting because of a signal, unregister the 3126 * gadget driver. */ 3127 if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) 3128 usb_gadget_unregister_driver(&fsg_driver); 3129 3130 /* Let the unbind and cleanup routines know the thread has exited */ 3131 complete_and_exit(&fsg->thread_notifier, 0); 3132} 3133 3134 3135/*-------------------------------------------------------------------------*/ 3136 3137static ssize_t show_ro(struct device *dev, struct device_attribute *attr, char *buf) 3138{ 3139 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 3140 3141 return sprintf(buf, "%d\n", curlun->ro); 3142} 3143 3144static ssize_t show_file(struct device *dev, struct device_attribute *attr, 3145 char *buf) 3146{ 3147 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 3148 struct fsg_dev *fsg = dev_get_drvdata(dev); 3149 char *p; 3150 ssize_t rc; 3151 3152 down_read(&fsg->filesem); 3153 if (fsg_lun_is_open(curlun)) { // Get the complete pathname 3154 p = d_path(&curlun->filp->f_path, buf, PAGE_SIZE - 1); 3155 if (IS_ERR(p)) 3156 rc = PTR_ERR(p); 3157 else { 3158 rc = strlen(p); 3159 memmove(buf, p, rc); 3160 buf[rc] = '\n'; // Add a newline 3161 buf[++rc] = 0; 3162 } 3163 } else { // No file, return 0 bytes 3164 *buf = 0; 3165 rc = 0; 3166 } 3167 up_read(&fsg->filesem); 3168 return rc; 3169} 3170 3171 3172static ssize_t store_ro(struct device *dev, struct device_attribute *attr, 3173 const char *buf, size_t count) 3174{ 3175 ssize_t rc = count; 3176 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 3177 struct fsg_dev *fsg = dev_get_drvdata(dev); 3178 int i; 3179 3180 if (sscanf(buf, "%d", &i) != 1) 3181 return -EINVAL; 3182 3183 /* Allow the write-enable status to change only while the backing file 3184 * is closed. */ 3185 down_read(&fsg->filesem); 3186 if (fsg_lun_is_open(curlun)) { 3187 LDBG(curlun, "read-only status change prevented\n"); 3188 rc = -EBUSY; 3189 } else { 3190 curlun->ro = !!i; 3191 LDBG(curlun, "read-only status set to %d\n", curlun->ro); 3192 } 3193 up_read(&fsg->filesem); 3194 return rc; 3195} 3196 3197static ssize_t store_file(struct device *dev, struct device_attribute *attr, 3198 const char *buf, size_t count) 3199{ 3200 struct fsg_lun *curlun = fsg_lun_from_dev(dev); 3201 struct fsg_dev *fsg = dev_get_drvdata(dev); 3202 int rc = 0; 3203 3204 if (curlun->prevent_medium_removal && fsg_lun_is_open(curlun)) { 3205 LDBG(curlun, "eject attempt prevented\n"); 3206 return -EBUSY; // "Door is locked" 3207 } 3208 3209 /* Remove a trailing newline */ 3210 if (count > 0 && buf[count-1] == '\n') 3211 ((char *) buf)[count-1] = 0; // Ugh! 3212 3213 /* Eject current medium */ 3214 down_write(&fsg->filesem); 3215 if (fsg_lun_is_open(curlun)) { 3216 fsg_lun_close(curlun); 3217 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT; 3218 } 3219 3220 /* Load new medium */ 3221 if (count > 0 && buf[0]) { 3222 rc = fsg_lun_open(curlun, buf); 3223 if (rc == 0) 3224 curlun->unit_attention_data = 3225 SS_NOT_READY_TO_READY_TRANSITION; 3226 } 3227 up_write(&fsg->filesem); 3228 return (rc < 0 ? rc : count); 3229} 3230 3231 3232/* The write permissions and store_xxx pointers are set in fsg_bind() */ 3233static DEVICE_ATTR(ro, 0444, show_ro, NULL); 3234static DEVICE_ATTR(file, 0444, show_file, NULL); 3235 3236 3237/*-------------------------------------------------------------------------*/ 3238 3239static void fsg_release(struct kref *ref) 3240{ 3241 struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref); 3242 3243 kfree(fsg->luns); 3244 kfree(fsg); 3245} 3246 3247static void lun_release(struct device *dev) 3248{ 3249 struct fsg_dev *fsg = dev_get_drvdata(dev); 3250 3251 kref_put(&fsg->ref, fsg_release); 3252} 3253 3254static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget) 3255{ 3256 struct fsg_dev *fsg = get_gadget_data(gadget); 3257 int i; 3258 struct fsg_lun *curlun; 3259 struct usb_request *req = fsg->ep0req; 3260 3261 DBG(fsg, "unbind\n"); 3262 clear_bit(REGISTERED, &fsg->atomic_bitflags); 3263 3264 /* Unregister the sysfs attribute files and the LUNs */ 3265 for (i = 0; i < fsg->nluns; ++i) { 3266 curlun = &fsg->luns[i]; 3267 if (curlun->registered) { 3268 device_remove_file(&curlun->dev, &dev_attr_ro); 3269 device_remove_file(&curlun->dev, &dev_attr_file); 3270 fsg_lun_close(curlun); 3271 device_unregister(&curlun->dev); 3272 curlun->registered = 0; 3273 } 3274 } 3275 3276 /* If the thread isn't already dead, tell it to exit now */ 3277 if (fsg->state != FSG_STATE_TERMINATED) { 3278 raise_exception(fsg, FSG_STATE_EXIT); 3279 wait_for_completion(&fsg->thread_notifier); 3280 3281 /* The cleanup routine waits for this completion also */ 3282 complete(&fsg->thread_notifier); 3283 } 3284 3285 /* Free the data buffers */ 3286 for (i = 0; i < FSG_NUM_BUFFERS; ++i) 3287 kfree(fsg->buffhds[i].buf); 3288 3289 /* Free the request and buffer for endpoint 0 */ 3290 if (req) { 3291 kfree(req->buf); 3292 usb_ep_free_request(fsg->ep0, req); 3293 } 3294 3295 set_gadget_data(gadget, NULL); 3296} 3297 3298 3299static int __init check_parameters(struct fsg_dev *fsg) 3300{ 3301 int prot; 3302 int gcnum; 3303 3304 /* Store the default values */ 3305 mod_data.transport_type = USB_PR_BULK; 3306 mod_data.transport_name = "Bulk-only"; 3307 mod_data.protocol_type = USB_SC_SCSI; 3308 mod_data.protocol_name = "Transparent SCSI"; 3309 3310 /* Some peripheral controllers are known not to be able to 3311 * halt bulk endpoints correctly. If one of them is present, 3312 * disable stalls. 3313 */ 3314 if (gadget_is_sh(fsg->gadget) || gadget_is_at91(fsg->gadget)) 3315 mod_data.can_stall = 0; 3316 3317 if (mod_data.release == 0xffff) { // Parameter wasn't set 3318 /* The sa1100 controller is not supported */ 3319 if (gadget_is_sa1100(fsg->gadget)) 3320 gcnum = -1; 3321 else 3322 gcnum = usb_gadget_controller_number(fsg->gadget); 3323 if (gcnum >= 0) 3324 mod_data.release = 0x0300 + gcnum; 3325 else { 3326 WARNING(fsg, "controller '%s' not recognized\n", 3327 fsg->gadget->name); 3328 mod_data.release = 0x0399; 3329 } 3330 } 3331 3332 prot = simple_strtol(mod_data.protocol_parm, NULL, 0); 3333 3334#ifdef CONFIG_USB_FILE_STORAGE_TEST 3335 if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) { 3336 ; // Use default setting 3337 } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) { 3338 mod_data.transport_type = USB_PR_CB; 3339 mod_data.transport_name = "Control-Bulk"; 3340 } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) { 3341 mod_data.transport_type = USB_PR_CBI; 3342 mod_data.transport_name = "Control-Bulk-Interrupt"; 3343 } else { 3344 ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm); 3345 return -EINVAL; 3346 } 3347 3348 if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 || 3349 prot == USB_SC_SCSI) { 3350 ; // Use default setting 3351 } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 || 3352 prot == USB_SC_RBC) { 3353 mod_data.protocol_type = USB_SC_RBC; 3354 mod_data.protocol_name = "RBC"; 3355 } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 || 3356 strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 || 3357 prot == USB_SC_8020) { 3358 mod_data.protocol_type = USB_SC_8020; 3359 mod_data.protocol_name = "8020i (ATAPI)"; 3360 } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 || 3361 prot == USB_SC_QIC) { 3362 mod_data.protocol_type = USB_SC_QIC; 3363 mod_data.protocol_name = "QIC-157"; 3364 } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 || 3365 prot == USB_SC_UFI) { 3366 mod_data.protocol_type = USB_SC_UFI; 3367 mod_data.protocol_name = "UFI"; 3368 } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 || 3369 prot == USB_SC_8070) { 3370 mod_data.protocol_type = USB_SC_8070; 3371 mod_data.protocol_name = "8070i"; 3372 } else { 3373 ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm); 3374 return -EINVAL; 3375 } 3376 3377 mod_data.buflen &= PAGE_CACHE_MASK; 3378 if (mod_data.buflen <= 0) { 3379 ERROR(fsg, "invalid buflen\n"); 3380 return -ETOOSMALL; 3381 } 3382#endif /* CONFIG_USB_FILE_STORAGE_TEST */ 3383 3384 return 0; 3385} 3386 3387 3388static int __init fsg_bind(struct usb_gadget *gadget) 3389{ 3390 struct fsg_dev *fsg = the_fsg; 3391 int rc; 3392 int i; 3393 struct fsg_lun *curlun; 3394 struct usb_ep *ep; 3395 struct usb_request *req; 3396 char *pathbuf, *p; 3397 3398 fsg->gadget = gadget; 3399 set_gadget_data(gadget, fsg); 3400 fsg->ep0 = gadget->ep0; 3401 fsg->ep0->driver_data = fsg; 3402 3403 if ((rc = check_parameters(fsg)) != 0) 3404 goto out; 3405 3406 if (mod_data.removable) { // Enable the store_xxx attributes 3407 dev_attr_file.attr.mode = 0644; 3408 dev_attr_file.store = store_file; 3409 if (!mod_data.cdrom) { 3410 dev_attr_ro.attr.mode = 0644; 3411 dev_attr_ro.store = store_ro; 3412 } 3413 } 3414 3415 /* Find out how many LUNs there should be */ 3416 i = mod_data.nluns; 3417 if (i == 0) 3418 i = max(mod_data.num_filenames, 1u); 3419 if (i > FSG_MAX_LUNS) { 3420 ERROR(fsg, "invalid number of LUNs: %d\n", i); 3421 rc = -EINVAL; 3422 goto out; 3423 } 3424 3425 /* Create the LUNs, open their backing files, and register the 3426 * LUN devices in sysfs. */ 3427 fsg->luns = kzalloc(i * sizeof(struct fsg_lun), GFP_KERNEL); 3428 if (!fsg->luns) { 3429 rc = -ENOMEM; 3430 goto out; 3431 } 3432 fsg->nluns = i; 3433 3434 for (i = 0; i < fsg->nluns; ++i) { 3435 curlun = &fsg->luns[i]; 3436 curlun->ro = mod_data.ro[i]; 3437 if (mod_data.cdrom) 3438 curlun->ro = 1; 3439 curlun->dev.release = lun_release; 3440 curlun->dev.parent = &gadget->dev; 3441 curlun->dev.driver = &fsg_driver.driver; 3442 dev_set_drvdata(&curlun->dev, fsg); 3443 dev_set_name(&curlun->dev,"%s-lun%d", 3444 dev_name(&gadget->dev), i); 3445 3446 if ((rc = device_register(&curlun->dev)) != 0) { 3447 INFO(fsg, "failed to register LUN%d: %d\n", i, rc); 3448 goto out; 3449 } 3450 if ((rc = device_create_file(&curlun->dev, 3451 &dev_attr_ro)) != 0 || 3452 (rc = device_create_file(&curlun->dev, 3453 &dev_attr_file)) != 0) { 3454 device_unregister(&curlun->dev); 3455 goto out; 3456 } 3457 curlun->registered = 1; 3458 kref_get(&fsg->ref); 3459 3460 if (mod_data.file[i] && *mod_data.file[i]) { 3461 if ((rc = fsg_lun_open(curlun, 3462 mod_data.file[i])) != 0) 3463 goto out; 3464 } else if (!mod_data.removable) { 3465 ERROR(fsg, "no file given for LUN%d\n", i); 3466 rc = -EINVAL; 3467 goto out; 3468 } 3469 } 3470 3471 /* Find all the endpoints we will use */ 3472 usb_ep_autoconfig_reset(gadget); 3473 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc); 3474 if (!ep) 3475 goto autoconf_fail; 3476 ep->driver_data = fsg; // claim the endpoint 3477 fsg->bulk_in = ep; 3478 3479 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc); 3480 if (!ep) 3481 goto autoconf_fail; 3482 ep->driver_data = fsg; // claim the endpoint 3483 fsg->bulk_out = ep; 3484 3485 if (transport_is_cbi()) { 3486 ep = usb_ep_autoconfig(gadget, &fsg_fs_intr_in_desc); 3487 if (!ep) 3488 goto autoconf_fail; 3489 ep->driver_data = fsg; // claim the endpoint 3490 fsg->intr_in = ep; 3491 } 3492 3493 /* Fix up the descriptors */ 3494 device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket; 3495 device_desc.idVendor = cpu_to_le16(mod_data.vendor); 3496 device_desc.idProduct = cpu_to_le16(mod_data.product); 3497 device_desc.bcdDevice = cpu_to_le16(mod_data.release); 3498 3499 i = (transport_is_cbi() ? 3 : 2); // Number of endpoints 3500 fsg_intf_desc.bNumEndpoints = i; 3501 fsg_intf_desc.bInterfaceSubClass = mod_data.protocol_type; 3502 fsg_intf_desc.bInterfaceProtocol = mod_data.transport_type; 3503 fsg_fs_function[i + FSG_FS_FUNCTION_PRE_EP_ENTRIES] = NULL; 3504 3505 if (gadget_is_dualspeed(gadget)) { 3506 fsg_hs_function[i + FSG_HS_FUNCTION_PRE_EP_ENTRIES] = NULL; 3507 3508 /* Assume ep0 uses the same maxpacket value for both speeds */ 3509 dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket; 3510 3511 /* Assume endpoint addresses are the same for both speeds */ 3512 fsg_hs_bulk_in_desc.bEndpointAddress = 3513 fsg_fs_bulk_in_desc.bEndpointAddress; 3514 fsg_hs_bulk_out_desc.bEndpointAddress = 3515 fsg_fs_bulk_out_desc.bEndpointAddress; 3516 fsg_hs_intr_in_desc.bEndpointAddress = 3517 fsg_fs_intr_in_desc.bEndpointAddress; 3518 } 3519 3520 if (gadget_is_otg(gadget)) 3521 fsg_otg_desc.bmAttributes |= USB_OTG_HNP; 3522 3523 rc = -ENOMEM; 3524 3525 /* Allocate the request and buffer for endpoint 0 */ 3526 fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL); 3527 if (!req) 3528 goto out; 3529 req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL); 3530 if (!req->buf) 3531 goto out; 3532 req->complete = ep0_complete; 3533 3534 /* Allocate the data buffers */ 3535 for (i = 0; i < FSG_NUM_BUFFERS; ++i) { 3536 struct fsg_buffhd *bh = &fsg->buffhds[i]; 3537 3538 /* Allocate for the bulk-in endpoint. We assume that 3539 * the buffer will also work with the bulk-out (and 3540 * interrupt-in) endpoint. */ 3541 bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL); 3542 if (!bh->buf) 3543 goto out; 3544 bh->next = bh + 1; 3545 } 3546 fsg->buffhds[FSG_NUM_BUFFERS - 1].next = &fsg->buffhds[0]; 3547 3548 /* This should reflect the actual gadget power source */ 3549 usb_gadget_set_selfpowered(gadget); 3550 3551 snprintf(fsg_string_manufacturer, sizeof fsg_string_manufacturer, 3552 "%s %s with %s", 3553 init_utsname()->sysname, init_utsname()->release, 3554 gadget->name); 3555 3556 /* On a real device, serial[] would be loaded from permanent 3557 * storage. We just encode it from the driver version string. */ 3558 for (i = 0; i < sizeof fsg_string_serial - 2; i += 2) { 3559 unsigned char c = DRIVER_VERSION[i / 2]; 3560 3561 if (!c) 3562 break; 3563 sprintf(&fsg_string_serial[i], "%02X", c); 3564 } 3565 3566 fsg->thread_task = kthread_create(fsg_main_thread, fsg, 3567 "file-storage-gadget"); 3568 if (IS_ERR(fsg->thread_task)) { 3569 rc = PTR_ERR(fsg->thread_task); 3570 goto out; 3571 } 3572 3573 INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n"); 3574 INFO(fsg, "Number of LUNs=%d\n", fsg->nluns); 3575 3576 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); 3577 for (i = 0; i < fsg->nluns; ++i) { 3578 curlun = &fsg->luns[i]; 3579 if (fsg_lun_is_open(curlun)) { 3580 p = NULL; 3581 if (pathbuf) { 3582 p = d_path(&curlun->filp->f_path, 3583 pathbuf, PATH_MAX); 3584 if (IS_ERR(p)) 3585 p = NULL; 3586 } 3587 LINFO(curlun, "ro=%d, file: %s\n", 3588 curlun->ro, (p ? p : "(error)")); 3589 } 3590 } 3591 kfree(pathbuf); 3592 3593 DBG(fsg, "transport=%s (x%02x)\n", 3594 mod_data.transport_name, mod_data.transport_type); 3595 DBG(fsg, "protocol=%s (x%02x)\n", 3596 mod_data.protocol_name, mod_data.protocol_type); 3597 DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n", 3598 mod_data.vendor, mod_data.product, mod_data.release); 3599 DBG(fsg, "removable=%d, stall=%d, cdrom=%d, buflen=%u\n", 3600 mod_data.removable, mod_data.can_stall, 3601 mod_data.cdrom, mod_data.buflen); 3602 DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task)); 3603 3604 set_bit(REGISTERED, &fsg->atomic_bitflags); 3605 3606 /* Tell the thread to start working */ 3607 wake_up_process(fsg->thread_task); 3608 return 0; 3609 3610autoconf_fail: 3611 ERROR(fsg, "unable to autoconfigure all endpoints\n"); 3612 rc = -ENOTSUPP; 3613 3614out: 3615 fsg->state = FSG_STATE_TERMINATED; // The thread is dead 3616 fsg_unbind(gadget); 3617 complete(&fsg->thread_notifier); 3618 return rc; 3619} 3620 3621 3622/*-------------------------------------------------------------------------*/ 3623 3624static void fsg_suspend(struct usb_gadget *gadget) 3625{ 3626 struct fsg_dev *fsg = get_gadget_data(gadget); 3627 3628 DBG(fsg, "suspend\n"); 3629 set_bit(SUSPENDED, &fsg->atomic_bitflags); 3630} 3631 3632static void fsg_resume(struct usb_gadget *gadget) 3633{ 3634 struct fsg_dev *fsg = get_gadget_data(gadget); 3635 3636 DBG(fsg, "resume\n"); 3637 clear_bit(SUSPENDED, &fsg->atomic_bitflags); 3638} 3639 3640 3641/*-------------------------------------------------------------------------*/ 3642 3643static struct usb_gadget_driver fsg_driver = { 3644#ifdef CONFIG_USB_GADGET_DUALSPEED 3645 .speed = USB_SPEED_HIGH, 3646#else 3647 .speed = USB_SPEED_FULL, 3648#endif 3649 .function = (char *) fsg_string_product, 3650 .bind = fsg_bind, 3651 .unbind = fsg_unbind, 3652 .disconnect = fsg_disconnect, 3653 .setup = fsg_setup, 3654 .suspend = fsg_suspend, 3655 .resume = fsg_resume, 3656 3657 .driver = { 3658 .name = DRIVER_NAME, 3659 .owner = THIS_MODULE, 3660 // .release = ... 3661 // .suspend = ... 3662 // .resume = ... 3663 }, 3664}; 3665 3666 3667static int __init fsg_alloc(void) 3668{ 3669 struct fsg_dev *fsg; 3670 3671 fsg = kzalloc(sizeof *fsg, GFP_KERNEL); 3672 if (!fsg) 3673 return -ENOMEM; 3674 spin_lock_init(&fsg->lock); 3675 init_rwsem(&fsg->filesem); 3676 kref_init(&fsg->ref); 3677 init_completion(&fsg->thread_notifier); 3678 3679 the_fsg = fsg; 3680 return 0; 3681} 3682 3683 3684static int __init fsg_init(void) 3685{ 3686 int rc; 3687 struct fsg_dev *fsg; 3688 3689 if ((rc = fsg_alloc()) != 0) 3690 return rc; 3691 fsg = the_fsg; 3692 if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0) 3693 kref_put(&fsg->ref, fsg_release); 3694 return rc; 3695} 3696module_init(fsg_init); 3697 3698 3699static void __exit fsg_cleanup(void) 3700{ 3701 struct fsg_dev *fsg = the_fsg; 3702 3703 /* Unregister the driver iff the thread hasn't already done so */ 3704 if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) 3705 usb_gadget_unregister_driver(&fsg_driver); 3706 3707 /* Wait for the thread to finish up */ 3708 wait_for_completion(&fsg->thread_notifier); 3709 3710 kref_put(&fsg->ref, fsg_release); 3711} 3712module_exit(fsg_cleanup); 3713