V4L/DVB (6715): ivtv: Remove unnecessary register update
[linux-2.6/verdex.git] / drivers / usb / gadget / file_storage.c
blob1d174dcb3ac9e6a4ea5ce8133d6e4519d32d9783
1 /*
2 * file_storage.c -- File-backed USB Storage Gadget, for USB development
4 * Copyright (C) 2003-2007 Alan Stern
5 * All rights reserved.
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.
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.
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.
40 * The File-backed Storage Gadget acts as a USB Mass Storage device,
41 * appearing to the host as a disk drive. In addition to providing an
42 * example of a genuinely useful gadget driver for a USB device, it also
43 * illustrates a technique of double-buffering for increased throughput.
44 * Last but not least, it gives an easy way to probe the behavior of the
45 * Mass Storage drivers in a USB host.
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. The gadget will indicate that
50 * it has removable media if the optional "removable" module parameter is set.
52 * The gadget supports the Control-Bulk (CB), Control-Bulk-Interrupt (CBI),
53 * and Bulk-Only (also known as Bulk-Bulk-Bulk or BBB) transports, selected
54 * by the optional "transport" module parameter. It also supports the
55 * following protocols: RBC (0x01), ATAPI or SFF-8020i (0x02), QIC-157 (0c03),
56 * UFI (0x04), SFF-8070i (0x05), and transparent SCSI (0x06), selected by
57 * the optional "protocol" module parameter. In addition, the default
58 * Vendor ID, Product ID, and release number can be overridden.
60 * There is support for multiple logical units (LUNs), each of which has
61 * its own backing file. The number of LUNs can be set using the optional
62 * "luns" module parameter (anywhere from 1 to 8), and the corresponding
63 * files are specified using comma-separated lists for "file" and "ro".
64 * The default number of LUNs is taken from the number of "file" elements;
65 * it is 1 if "file" is not given. If "removable" is not set then a backing
66 * file must be specified for each LUN. If it is set, then an unspecified
67 * or empty backing filename means the LUN's medium is not loaded.
69 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
70 * needed (an interrupt-out endpoint is also needed for CBI). The memory
71 * requirement amounts to two 16K buffers, size configurable by a parameter.
72 * Support is included for both full-speed and high-speed operation.
74 * Note that the driver is slightly non-portable in that it assumes a
75 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
76 * interrupt-in endpoints. With most device controllers this isn't an
77 * issue, but there may be some with hardware restrictions that prevent
78 * a buffer from being used by more than one endpoint.
80 * Module options:
82 * file=filename[,filename...]
83 * Required if "removable" is not set, names of
84 * the files or block devices used for
85 * backing storage
86 * ro=b[,b...] Default false, booleans for read-only access
87 * removable Default false, boolean for removable media
88 * luns=N Default N = number of filenames, number of
89 * LUNs to support
90 * stall Default determined according to the type of
91 * USB device controller (usually true),
92 * boolean to permit the driver to halt
93 * bulk endpoints
94 * transport=XXX Default BBB, transport name (CB, CBI, or BBB)
95 * protocol=YYY Default SCSI, protocol name (RBC, 8020 or
96 * ATAPI, QIC, UFI, 8070, or SCSI;
97 * also 1 - 6)
98 * vendor=0xVVVV Default 0x0525 (NetChip), USB Vendor ID
99 * product=0xPPPP Default 0xa4a5 (FSG), USB Product ID
100 * release=0xRRRR Override the USB release number (bcdDevice)
101 * buflen=N Default N=16384, buffer size used (will be
102 * rounded down to a multiple of
103 * PAGE_CACHE_SIZE)
105 * If CONFIG_USB_FILE_STORAGE_TEST is not set, only the "file", "ro",
106 * "removable", "luns", and "stall" options are available; default values
107 * are used for everything else.
109 * The pathnames of the backing files and the ro settings are available in
110 * the attribute files "file" and "ro" in the lun<n> subdirectory of the
111 * gadget's sysfs directory. If the "removable" option is set, writing to
112 * these files will simulate ejecting/loading the medium (writing an empty
113 * line means eject) and adjusting a write-enable tab. Changes to the ro
114 * setting are not allowed when the medium is loaded.
116 * This gadget driver is heavily based on "Gadget Zero" by David Brownell.
117 * The driver's SCSI command interface was based on the "Information
118 * technology - Small Computer System Interface - 2" document from
119 * X3T9.2 Project 375D, Revision 10L, 7-SEP-93, available at
120 * <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>. The single exception
121 * is opcode 0x23 (READ FORMAT CAPACITIES), which was based on the
122 * "Universal Serial Bus Mass Storage Class UFI Command Specification"
123 * document, Revision 1.0, December 14, 1998, available at
124 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
129 * Driver Design
131 * The FSG driver is fairly straightforward. There is a main kernel
132 * thread that handles most of the work. Interrupt routines field
133 * callbacks from the controller driver: bulk- and interrupt-request
134 * completion notifications, endpoint-0 events, and disconnect events.
135 * Completion events are passed to the main thread by wakeup calls. Many
136 * ep0 requests are handled at interrupt time, but SetInterface,
137 * SetConfiguration, and device reset requests are forwarded to the
138 * thread in the form of "exceptions" using SIGUSR1 signals (since they
139 * should interrupt any ongoing file I/O operations).
141 * The thread's main routine implements the standard command/data/status
142 * parts of a SCSI interaction. It and its subroutines are full of tests
143 * for pending signals/exceptions -- all this polling is necessary since
144 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
145 * indication that the driver really wants to be running in userspace.)
146 * An important point is that so long as the thread is alive it keeps an
147 * open reference to the backing file. This will prevent unmounting
148 * the backing file's underlying filesystem and could cause problems
149 * during system shutdown, for example. To prevent such problems, the
150 * thread catches INT, TERM, and KILL signals and converts them into
151 * an EXIT exception.
153 * In normal operation the main thread is started during the gadget's
154 * fsg_bind() callback and stopped during fsg_unbind(). But it can also
155 * exit when it receives a signal, and there's no point leaving the
156 * gadget running when the thread is dead. So just before the thread
157 * exits, it deregisters the gadget driver. This makes things a little
158 * tricky: The driver is deregistered at two places, and the exiting
159 * thread can indirectly call fsg_unbind() which in turn can tell the
160 * thread to exit. The first problem is resolved through the use of the
161 * REGISTERED atomic bitflag; the driver will only be deregistered once.
162 * The second problem is resolved by having fsg_unbind() check
163 * fsg->state; it won't try to stop the thread if the state is already
164 * FSG_STATE_TERMINATED.
166 * To provide maximum throughput, the driver uses a circular pipeline of
167 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
168 * arbitrarily long; in practice the benefits don't justify having more
169 * than 2 stages (i.e., double buffering). But it helps to think of the
170 * pipeline as being a long one. Each buffer head contains a bulk-in and
171 * a bulk-out request pointer (since the buffer can be used for both
172 * output and input -- directions always are given from the host's
173 * point of view) as well as a pointer to the buffer and various state
174 * variables.
176 * Use of the pipeline follows a simple protocol. There is a variable
177 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
178 * At any time that buffer head may still be in use from an earlier
179 * request, so each buffer head has a state variable indicating whether
180 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
181 * buffer head to be EMPTY, filling the buffer either by file I/O or by
182 * USB I/O (during which the buffer head is BUSY), and marking the buffer
183 * head FULL when the I/O is complete. Then the buffer will be emptied
184 * (again possibly by USB I/O, during which it is marked BUSY) and
185 * finally marked EMPTY again (possibly by a completion routine).
187 * A module parameter tells the driver to avoid stalling the bulk
188 * endpoints wherever the transport specification allows. This is
189 * necessary for some UDCs like the SuperH, which cannot reliably clear a
190 * halt on a bulk endpoint. However, under certain circumstances the
191 * Bulk-only specification requires a stall. In such cases the driver
192 * will halt the endpoint and set a flag indicating that it should clear
193 * the halt in software during the next device reset. Hopefully this
194 * will permit everything to work correctly. Furthermore, although the
195 * specification allows the bulk-out endpoint to halt when the host sends
196 * too much data, implementing this would cause an unavoidable race.
197 * The driver will always use the "no-stall" approach for OUT transfers.
199 * One subtle point concerns sending status-stage responses for ep0
200 * requests. Some of these requests, such as device reset, can involve
201 * interrupting an ongoing file I/O operation, which might take an
202 * arbitrarily long time. During that delay the host might give up on
203 * the original ep0 request and issue a new one. When that happens the
204 * driver should not notify the host about completion of the original
205 * request, as the host will no longer be waiting for it. So the driver
206 * assigns to each ep0 request a unique tag, and it keeps track of the
207 * tag value of the request associated with a long-running exception
208 * (device-reset, interface-change, or configuration-change). When the
209 * exception handler is finished, the status-stage response is submitted
210 * only if the current ep0 request tag is equal to the exception request
211 * tag. Thus only the most recently received ep0 request will get a
212 * status-stage response.
214 * Warning: This driver source file is too long. It ought to be split up
215 * into a header file plus about 3 separate .c files, to handle the details
216 * of the Gadget, USB Mass Storage, and SCSI protocols.
220 /* #define VERBOSE_DEBUG */
221 /* #define DUMP_MSGS */
224 #include <linux/blkdev.h>
225 #include <linux/completion.h>
226 #include <linux/dcache.h>
227 #include <linux/delay.h>
228 #include <linux/device.h>
229 #include <linux/fcntl.h>
230 #include <linux/file.h>
231 #include <linux/fs.h>
232 #include <linux/kref.h>
233 #include <linux/kthread.h>
234 #include <linux/limits.h>
235 #include <linux/rwsem.h>
236 #include <linux/slab.h>
237 #include <linux/spinlock.h>
238 #include <linux/string.h>
239 #include <linux/freezer.h>
240 #include <linux/utsname.h>
242 #include <linux/usb/ch9.h>
243 #include <linux/usb/gadget.h>
245 #include "gadget_chips.h"
248 /*-------------------------------------------------------------------------*/
250 #define DRIVER_DESC "File-backed Storage Gadget"
251 #define DRIVER_NAME "g_file_storage"
252 #define DRIVER_VERSION "7 August 2007"
254 static const char longname[] = DRIVER_DESC;
255 static const char shortname[] = DRIVER_NAME;
257 MODULE_DESCRIPTION(DRIVER_DESC);
258 MODULE_AUTHOR("Alan Stern");
259 MODULE_LICENSE("Dual BSD/GPL");
261 /* Thanks to NetChip Technologies for donating this product ID.
263 * DO NOT REUSE THESE IDs with any other driver!! Ever!!
264 * Instead: allocate your own, using normal USB-IF procedures. */
265 #define DRIVER_VENDOR_ID 0x0525 // NetChip
266 #define DRIVER_PRODUCT_ID 0xa4a5 // Linux-USB File-backed Storage Gadget
270 * This driver assumes self-powered hardware and has no way for users to
271 * trigger remote wakeup. It uses autoconfiguration to select endpoints
272 * and endpoint addresses.
276 /*-------------------------------------------------------------------------*/
278 #ifdef DEBUG
279 #define LDBG(lun,fmt,args...) \
280 dev_dbg(&(lun)->dev , fmt , ## args)
281 #define MDBG(fmt,args...) \
282 printk(KERN_DEBUG DRIVER_NAME ": " fmt , ## args)
283 #else
284 #define LDBG(lun,fmt,args...) \
285 do { } while (0)
286 #define MDBG(fmt,args...) \
287 do { } while (0)
288 #undef VERBOSE_DEBUG
289 #undef DUMP_MSGS
290 #endif /* DEBUG */
292 #ifdef VERBOSE_DEBUG
293 #define VLDBG LDBG
294 #else
295 #define VLDBG(lun,fmt,args...) \
296 do { } while (0)
297 #endif /* VERBOSE_DEBUG */
299 #define LERROR(lun,fmt,args...) \
300 dev_err(&(lun)->dev , fmt , ## args)
301 #define LWARN(lun,fmt,args...) \
302 dev_warn(&(lun)->dev , fmt , ## args)
303 #define LINFO(lun,fmt,args...) \
304 dev_info(&(lun)->dev , fmt , ## args)
306 #define MINFO(fmt,args...) \
307 printk(KERN_INFO DRIVER_NAME ": " fmt , ## args)
309 #define DBG(d, fmt, args...) \
310 dev_dbg(&(d)->gadget->dev , fmt , ## args)
311 #define VDBG(d, fmt, args...) \
312 dev_vdbg(&(d)->gadget->dev , fmt , ## args)
313 #define ERROR(d, fmt, args...) \
314 dev_err(&(d)->gadget->dev , fmt , ## args)
315 #define WARN(d, fmt, args...) \
316 dev_warn(&(d)->gadget->dev , fmt , ## args)
317 #define INFO(d, fmt, args...) \
318 dev_info(&(d)->gadget->dev , fmt , ## args)
321 /*-------------------------------------------------------------------------*/
323 /* Encapsulate the module parameter settings */
325 #define MAX_LUNS 8
327 static struct {
328 char *file[MAX_LUNS];
329 int ro[MAX_LUNS];
330 unsigned int num_filenames;
331 unsigned int num_ros;
332 unsigned int nluns;
334 int removable;
335 int can_stall;
337 char *transport_parm;
338 char *protocol_parm;
339 unsigned short vendor;
340 unsigned short product;
341 unsigned short release;
342 unsigned int buflen;
344 int transport_type;
345 char *transport_name;
346 int protocol_type;
347 char *protocol_name;
349 } mod_data = { // Default values
350 .transport_parm = "BBB",
351 .protocol_parm = "SCSI",
352 .removable = 0,
353 .can_stall = 1,
354 .vendor = DRIVER_VENDOR_ID,
355 .product = DRIVER_PRODUCT_ID,
356 .release = 0xffff, // Use controller chip type
357 .buflen = 16384,
361 module_param_array_named(file, mod_data.file, charp, &mod_data.num_filenames,
362 S_IRUGO);
363 MODULE_PARM_DESC(file, "names of backing files or devices");
365 module_param_array_named(ro, mod_data.ro, bool, &mod_data.num_ros, S_IRUGO);
366 MODULE_PARM_DESC(ro, "true to force read-only");
368 module_param_named(luns, mod_data.nluns, uint, S_IRUGO);
369 MODULE_PARM_DESC(luns, "number of LUNs");
371 module_param_named(removable, mod_data.removable, bool, S_IRUGO);
372 MODULE_PARM_DESC(removable, "true to simulate removable media");
374 module_param_named(stall, mod_data.can_stall, bool, S_IRUGO);
375 MODULE_PARM_DESC(stall, "false to prevent bulk stalls");
378 /* In the non-TEST version, only the module parameters listed above
379 * are available. */
380 #ifdef CONFIG_USB_FILE_STORAGE_TEST
382 module_param_named(transport, mod_data.transport_parm, charp, S_IRUGO);
383 MODULE_PARM_DESC(transport, "type of transport (BBB, CBI, or CB)");
385 module_param_named(protocol, mod_data.protocol_parm, charp, S_IRUGO);
386 MODULE_PARM_DESC(protocol, "type of protocol (RBC, 8020, QIC, UFI, "
387 "8070, or SCSI)");
389 module_param_named(vendor, mod_data.vendor, ushort, S_IRUGO);
390 MODULE_PARM_DESC(vendor, "USB Vendor ID");
392 module_param_named(product, mod_data.product, ushort, S_IRUGO);
393 MODULE_PARM_DESC(product, "USB Product ID");
395 module_param_named(release, mod_data.release, ushort, S_IRUGO);
396 MODULE_PARM_DESC(release, "USB release number");
398 module_param_named(buflen, mod_data.buflen, uint, S_IRUGO);
399 MODULE_PARM_DESC(buflen, "I/O buffer size");
401 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
404 /*-------------------------------------------------------------------------*/
406 /* USB protocol value = the transport method */
407 #define USB_PR_CBI 0x00 // Control/Bulk/Interrupt
408 #define USB_PR_CB 0x01 // Control/Bulk w/o interrupt
409 #define USB_PR_BULK 0x50 // Bulk-only
411 /* USB subclass value = the protocol encapsulation */
412 #define USB_SC_RBC 0x01 // Reduced Block Commands (flash)
413 #define USB_SC_8020 0x02 // SFF-8020i, MMC-2, ATAPI (CD-ROM)
414 #define USB_SC_QIC 0x03 // QIC-157 (tape)
415 #define USB_SC_UFI 0x04 // UFI (floppy)
416 #define USB_SC_8070 0x05 // SFF-8070i (removable)
417 #define USB_SC_SCSI 0x06 // Transparent SCSI
419 /* Bulk-only data structures */
421 /* Command Block Wrapper */
422 struct bulk_cb_wrap {
423 __le32 Signature; // Contains 'USBC'
424 u32 Tag; // Unique per command id
425 __le32 DataTransferLength; // Size of the data
426 u8 Flags; // Direction in bit 7
427 u8 Lun; // LUN (normally 0)
428 u8 Length; // Of the CDB, <= MAX_COMMAND_SIZE
429 u8 CDB[16]; // Command Data Block
432 #define USB_BULK_CB_WRAP_LEN 31
433 #define USB_BULK_CB_SIG 0x43425355 // Spells out USBC
434 #define USB_BULK_IN_FLAG 0x80
436 /* Command Status Wrapper */
437 struct bulk_cs_wrap {
438 __le32 Signature; // Should = 'USBS'
439 u32 Tag; // Same as original command
440 __le32 Residue; // Amount not transferred
441 u8 Status; // See below
444 #define USB_BULK_CS_WRAP_LEN 13
445 #define USB_BULK_CS_SIG 0x53425355 // Spells out 'USBS'
446 #define USB_STATUS_PASS 0
447 #define USB_STATUS_FAIL 1
448 #define USB_STATUS_PHASE_ERROR 2
450 /* Bulk-only class specific requests */
451 #define USB_BULK_RESET_REQUEST 0xff
452 #define USB_BULK_GET_MAX_LUN_REQUEST 0xfe
455 /* CBI Interrupt data structure */
456 struct interrupt_data {
457 u8 bType;
458 u8 bValue;
461 #define CBI_INTERRUPT_DATA_LEN 2
463 /* CBI Accept Device-Specific Command request */
464 #define USB_CBI_ADSC_REQUEST 0x00
467 #define MAX_COMMAND_SIZE 16 // Length of a SCSI Command Data Block
469 /* SCSI commands that we recognize */
470 #define SC_FORMAT_UNIT 0x04
471 #define SC_INQUIRY 0x12
472 #define SC_MODE_SELECT_6 0x15
473 #define SC_MODE_SELECT_10 0x55
474 #define SC_MODE_SENSE_6 0x1a
475 #define SC_MODE_SENSE_10 0x5a
476 #define SC_PREVENT_ALLOW_MEDIUM_REMOVAL 0x1e
477 #define SC_READ_6 0x08
478 #define SC_READ_10 0x28
479 #define SC_READ_12 0xa8
480 #define SC_READ_CAPACITY 0x25
481 #define SC_READ_FORMAT_CAPACITIES 0x23
482 #define SC_RELEASE 0x17
483 #define SC_REQUEST_SENSE 0x03
484 #define SC_RESERVE 0x16
485 #define SC_SEND_DIAGNOSTIC 0x1d
486 #define SC_START_STOP_UNIT 0x1b
487 #define SC_SYNCHRONIZE_CACHE 0x35
488 #define SC_TEST_UNIT_READY 0x00
489 #define SC_VERIFY 0x2f
490 #define SC_WRITE_6 0x0a
491 #define SC_WRITE_10 0x2a
492 #define SC_WRITE_12 0xaa
494 /* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
495 #define SS_NO_SENSE 0
496 #define SS_COMMUNICATION_FAILURE 0x040800
497 #define SS_INVALID_COMMAND 0x052000
498 #define SS_INVALID_FIELD_IN_CDB 0x052400
499 #define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE 0x052100
500 #define SS_LOGICAL_UNIT_NOT_SUPPORTED 0x052500
501 #define SS_MEDIUM_NOT_PRESENT 0x023a00
502 #define SS_MEDIUM_REMOVAL_PREVENTED 0x055302
503 #define SS_NOT_READY_TO_READY_TRANSITION 0x062800
504 #define SS_RESET_OCCURRED 0x062900
505 #define SS_SAVING_PARAMETERS_NOT_SUPPORTED 0x053900
506 #define SS_UNRECOVERED_READ_ERROR 0x031100
507 #define SS_WRITE_ERROR 0x030c02
508 #define SS_WRITE_PROTECTED 0x072700
510 #define SK(x) ((u8) ((x) >> 16)) // Sense Key byte, etc.
511 #define ASC(x) ((u8) ((x) >> 8))
512 #define ASCQ(x) ((u8) (x))
515 /*-------------------------------------------------------------------------*/
518 * These definitions will permit the compiler to avoid generating code for
519 * parts of the driver that aren't used in the non-TEST version. Even gcc
520 * can recognize when a test of a constant expression yields a dead code
521 * path.
524 #ifdef CONFIG_USB_FILE_STORAGE_TEST
526 #define transport_is_bbb() (mod_data.transport_type == USB_PR_BULK)
527 #define transport_is_cbi() (mod_data.transport_type == USB_PR_CBI)
528 #define protocol_is_scsi() (mod_data.protocol_type == USB_SC_SCSI)
530 #else
532 #define transport_is_bbb() 1
533 #define transport_is_cbi() 0
534 #define protocol_is_scsi() 1
536 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
539 struct lun {
540 struct file *filp;
541 loff_t file_length;
542 loff_t num_sectors;
544 unsigned int ro : 1;
545 unsigned int prevent_medium_removal : 1;
546 unsigned int registered : 1;
547 unsigned int info_valid : 1;
549 u32 sense_data;
550 u32 sense_data_info;
551 u32 unit_attention_data;
553 struct device dev;
556 #define backing_file_is_open(curlun) ((curlun)->filp != NULL)
558 static struct lun *dev_to_lun(struct device *dev)
560 return container_of(dev, struct lun, dev);
564 /* Big enough to hold our biggest descriptor */
565 #define EP0_BUFSIZE 256
566 #define DELAYED_STATUS (EP0_BUFSIZE + 999) // An impossibly large value
568 /* Number of buffers we will use. 2 is enough for double-buffering */
569 #define NUM_BUFFERS 2
571 enum fsg_buffer_state {
572 BUF_STATE_EMPTY = 0,
573 BUF_STATE_FULL,
574 BUF_STATE_BUSY
577 struct fsg_buffhd {
578 void *buf;
579 enum fsg_buffer_state state;
580 struct fsg_buffhd *next;
582 /* The NetChip 2280 is faster, and handles some protocol faults
583 * better, if we don't submit any short bulk-out read requests.
584 * So we will record the intended request length here. */
585 unsigned int bulk_out_intended_length;
587 struct usb_request *inreq;
588 int inreq_busy;
589 struct usb_request *outreq;
590 int outreq_busy;
593 enum fsg_state {
594 FSG_STATE_COMMAND_PHASE = -10, // This one isn't used anywhere
595 FSG_STATE_DATA_PHASE,
596 FSG_STATE_STATUS_PHASE,
598 FSG_STATE_IDLE = 0,
599 FSG_STATE_ABORT_BULK_OUT,
600 FSG_STATE_RESET,
601 FSG_STATE_INTERFACE_CHANGE,
602 FSG_STATE_CONFIG_CHANGE,
603 FSG_STATE_DISCONNECT,
604 FSG_STATE_EXIT,
605 FSG_STATE_TERMINATED
608 enum data_direction {
609 DATA_DIR_UNKNOWN = 0,
610 DATA_DIR_FROM_HOST,
611 DATA_DIR_TO_HOST,
612 DATA_DIR_NONE
615 struct fsg_dev {
616 /* lock protects: state, all the req_busy's, and cbbuf_cmnd */
617 spinlock_t lock;
618 struct usb_gadget *gadget;
620 /* filesem protects: backing files in use */
621 struct rw_semaphore filesem;
623 /* reference counting: wait until all LUNs are released */
624 struct kref ref;
626 struct usb_ep *ep0; // Handy copy of gadget->ep0
627 struct usb_request *ep0req; // For control responses
628 unsigned int ep0_req_tag;
629 const char *ep0req_name;
631 struct usb_request *intreq; // For interrupt responses
632 int intreq_busy;
633 struct fsg_buffhd *intr_buffhd;
635 unsigned int bulk_out_maxpacket;
636 enum fsg_state state; // For exception handling
637 unsigned int exception_req_tag;
639 u8 config, new_config;
641 unsigned int running : 1;
642 unsigned int bulk_in_enabled : 1;
643 unsigned int bulk_out_enabled : 1;
644 unsigned int intr_in_enabled : 1;
645 unsigned int phase_error : 1;
646 unsigned int short_packet_received : 1;
647 unsigned int bad_lun_okay : 1;
649 unsigned long atomic_bitflags;
650 #define REGISTERED 0
651 #define CLEAR_BULK_HALTS 1
652 #define SUSPENDED 2
654 struct usb_ep *bulk_in;
655 struct usb_ep *bulk_out;
656 struct usb_ep *intr_in;
658 struct fsg_buffhd *next_buffhd_to_fill;
659 struct fsg_buffhd *next_buffhd_to_drain;
660 struct fsg_buffhd buffhds[NUM_BUFFERS];
662 int thread_wakeup_needed;
663 struct completion thread_notifier;
664 struct task_struct *thread_task;
666 int cmnd_size;
667 u8 cmnd[MAX_COMMAND_SIZE];
668 enum data_direction data_dir;
669 u32 data_size;
670 u32 data_size_from_cmnd;
671 u32 tag;
672 unsigned int lun;
673 u32 residue;
674 u32 usb_amount_left;
676 /* The CB protocol offers no way for a host to know when a command
677 * has completed. As a result the next command may arrive early,
678 * and we will still have to handle it. For that reason we need
679 * a buffer to store new commands when using CB (or CBI, which
680 * does not oblige a host to wait for command completion either). */
681 int cbbuf_cmnd_size;
682 u8 cbbuf_cmnd[MAX_COMMAND_SIZE];
684 unsigned int nluns;
685 struct lun *luns;
686 struct lun *curlun;
689 typedef void (*fsg_routine_t)(struct fsg_dev *);
691 static int exception_in_progress(struct fsg_dev *fsg)
693 return (fsg->state > FSG_STATE_IDLE);
696 /* Make bulk-out requests be divisible by the maxpacket size */
697 static void set_bulk_out_req_length(struct fsg_dev *fsg,
698 struct fsg_buffhd *bh, unsigned int length)
700 unsigned int rem;
702 bh->bulk_out_intended_length = length;
703 rem = length % fsg->bulk_out_maxpacket;
704 if (rem > 0)
705 length += fsg->bulk_out_maxpacket - rem;
706 bh->outreq->length = length;
709 static struct fsg_dev *the_fsg;
710 static struct usb_gadget_driver fsg_driver;
712 static void close_backing_file(struct lun *curlun);
713 static void close_all_backing_files(struct fsg_dev *fsg);
716 /*-------------------------------------------------------------------------*/
718 #ifdef DUMP_MSGS
720 static void dump_msg(struct fsg_dev *fsg, const char *label,
721 const u8 *buf, unsigned int length)
723 if (length < 512) {
724 DBG(fsg, "%s, length %u:\n", label, length);
725 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
726 16, 1, buf, length, 0);
730 static void dump_cdb(struct fsg_dev *fsg)
733 #else
735 static void dump_msg(struct fsg_dev *fsg, const char *label,
736 const u8 *buf, unsigned int length)
739 #ifdef VERBOSE_DEBUG
741 static void dump_cdb(struct fsg_dev *fsg)
743 print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,
744 16, 1, fsg->cmnd, fsg->cmnd_size, 0);
747 #else
749 static void dump_cdb(struct fsg_dev *fsg)
752 #endif /* VERBOSE_DEBUG */
753 #endif /* DUMP_MSGS */
756 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
758 const char *name;
760 if (ep == fsg->bulk_in)
761 name = "bulk-in";
762 else if (ep == fsg->bulk_out)
763 name = "bulk-out";
764 else
765 name = ep->name;
766 DBG(fsg, "%s set halt\n", name);
767 return usb_ep_set_halt(ep);
771 /*-------------------------------------------------------------------------*/
773 /* Routines for unaligned data access */
775 static u16 get_be16(u8 *buf)
777 return ((u16) buf[0] << 8) | ((u16) buf[1]);
780 static u32 get_be32(u8 *buf)
782 return ((u32) buf[0] << 24) | ((u32) buf[1] << 16) |
783 ((u32) buf[2] << 8) | ((u32) buf[3]);
786 static void put_be16(u8 *buf, u16 val)
788 buf[0] = val >> 8;
789 buf[1] = val;
792 static void put_be32(u8 *buf, u32 val)
794 buf[0] = val >> 24;
795 buf[1] = val >> 16;
796 buf[2] = val >> 8;
797 buf[3] = val & 0xff;
801 /*-------------------------------------------------------------------------*/
804 * DESCRIPTORS ... most are static, but strings and (full) configuration
805 * descriptors are built on demand. Also the (static) config and interface
806 * descriptors are adjusted during fsg_bind().
808 #define STRING_MANUFACTURER 1
809 #define STRING_PRODUCT 2
810 #define STRING_SERIAL 3
811 #define STRING_CONFIG 4
812 #define STRING_INTERFACE 5
814 /* There is only one configuration. */
815 #define CONFIG_VALUE 1
817 static struct usb_device_descriptor
818 device_desc = {
819 .bLength = sizeof device_desc,
820 .bDescriptorType = USB_DT_DEVICE,
822 .bcdUSB = __constant_cpu_to_le16(0x0200),
823 .bDeviceClass = USB_CLASS_PER_INTERFACE,
825 /* The next three values can be overridden by module parameters */
826 .idVendor = __constant_cpu_to_le16(DRIVER_VENDOR_ID),
827 .idProduct = __constant_cpu_to_le16(DRIVER_PRODUCT_ID),
828 .bcdDevice = __constant_cpu_to_le16(0xffff),
830 .iManufacturer = STRING_MANUFACTURER,
831 .iProduct = STRING_PRODUCT,
832 .iSerialNumber = STRING_SERIAL,
833 .bNumConfigurations = 1,
836 static struct usb_config_descriptor
837 config_desc = {
838 .bLength = sizeof config_desc,
839 .bDescriptorType = USB_DT_CONFIG,
841 /* wTotalLength computed by usb_gadget_config_buf() */
842 .bNumInterfaces = 1,
843 .bConfigurationValue = CONFIG_VALUE,
844 .iConfiguration = STRING_CONFIG,
845 .bmAttributes = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
846 .bMaxPower = 1, // self-powered
849 static struct usb_otg_descriptor
850 otg_desc = {
851 .bLength = sizeof(otg_desc),
852 .bDescriptorType = USB_DT_OTG,
854 .bmAttributes = USB_OTG_SRP,
857 /* There is only one interface. */
859 static struct usb_interface_descriptor
860 intf_desc = {
861 .bLength = sizeof intf_desc,
862 .bDescriptorType = USB_DT_INTERFACE,
864 .bNumEndpoints = 2, // Adjusted during fsg_bind()
865 .bInterfaceClass = USB_CLASS_MASS_STORAGE,
866 .bInterfaceSubClass = USB_SC_SCSI, // Adjusted during fsg_bind()
867 .bInterfaceProtocol = USB_PR_BULK, // Adjusted during fsg_bind()
868 .iInterface = STRING_INTERFACE,
871 /* Three full-speed endpoint descriptors: bulk-in, bulk-out,
872 * and interrupt-in. */
874 static struct usb_endpoint_descriptor
875 fs_bulk_in_desc = {
876 .bLength = USB_DT_ENDPOINT_SIZE,
877 .bDescriptorType = USB_DT_ENDPOINT,
879 .bEndpointAddress = USB_DIR_IN,
880 .bmAttributes = USB_ENDPOINT_XFER_BULK,
881 /* wMaxPacketSize set by autoconfiguration */
884 static struct usb_endpoint_descriptor
885 fs_bulk_out_desc = {
886 .bLength = USB_DT_ENDPOINT_SIZE,
887 .bDescriptorType = USB_DT_ENDPOINT,
889 .bEndpointAddress = USB_DIR_OUT,
890 .bmAttributes = USB_ENDPOINT_XFER_BULK,
891 /* wMaxPacketSize set by autoconfiguration */
894 static struct usb_endpoint_descriptor
895 fs_intr_in_desc = {
896 .bLength = USB_DT_ENDPOINT_SIZE,
897 .bDescriptorType = USB_DT_ENDPOINT,
899 .bEndpointAddress = USB_DIR_IN,
900 .bmAttributes = USB_ENDPOINT_XFER_INT,
901 .wMaxPacketSize = __constant_cpu_to_le16(2),
902 .bInterval = 32, // frames -> 32 ms
905 static const struct usb_descriptor_header *fs_function[] = {
906 (struct usb_descriptor_header *) &otg_desc,
907 (struct usb_descriptor_header *) &intf_desc,
908 (struct usb_descriptor_header *) &fs_bulk_in_desc,
909 (struct usb_descriptor_header *) &fs_bulk_out_desc,
910 (struct usb_descriptor_header *) &fs_intr_in_desc,
911 NULL,
913 #define FS_FUNCTION_PRE_EP_ENTRIES 2
917 * USB 2.0 devices need to expose both high speed and full speed
918 * descriptors, unless they only run at full speed.
920 * That means alternate endpoint descriptors (bigger packets)
921 * and a "device qualifier" ... plus more construction options
922 * for the config descriptor.
924 static struct usb_qualifier_descriptor
925 dev_qualifier = {
926 .bLength = sizeof dev_qualifier,
927 .bDescriptorType = USB_DT_DEVICE_QUALIFIER,
929 .bcdUSB = __constant_cpu_to_le16(0x0200),
930 .bDeviceClass = USB_CLASS_PER_INTERFACE,
932 .bNumConfigurations = 1,
935 static struct usb_endpoint_descriptor
936 hs_bulk_in_desc = {
937 .bLength = USB_DT_ENDPOINT_SIZE,
938 .bDescriptorType = USB_DT_ENDPOINT,
940 /* bEndpointAddress copied from fs_bulk_in_desc during fsg_bind() */
941 .bmAttributes = USB_ENDPOINT_XFER_BULK,
942 .wMaxPacketSize = __constant_cpu_to_le16(512),
945 static struct usb_endpoint_descriptor
946 hs_bulk_out_desc = {
947 .bLength = USB_DT_ENDPOINT_SIZE,
948 .bDescriptorType = USB_DT_ENDPOINT,
950 /* bEndpointAddress copied from fs_bulk_out_desc during fsg_bind() */
951 .bmAttributes = USB_ENDPOINT_XFER_BULK,
952 .wMaxPacketSize = __constant_cpu_to_le16(512),
953 .bInterval = 1, // NAK every 1 uframe
956 static struct usb_endpoint_descriptor
957 hs_intr_in_desc = {
958 .bLength = USB_DT_ENDPOINT_SIZE,
959 .bDescriptorType = USB_DT_ENDPOINT,
961 /* bEndpointAddress copied from fs_intr_in_desc during fsg_bind() */
962 .bmAttributes = USB_ENDPOINT_XFER_INT,
963 .wMaxPacketSize = __constant_cpu_to_le16(2),
964 .bInterval = 9, // 2**(9-1) = 256 uframes -> 32 ms
967 static const struct usb_descriptor_header *hs_function[] = {
968 (struct usb_descriptor_header *) &otg_desc,
969 (struct usb_descriptor_header *) &intf_desc,
970 (struct usb_descriptor_header *) &hs_bulk_in_desc,
971 (struct usb_descriptor_header *) &hs_bulk_out_desc,
972 (struct usb_descriptor_header *) &hs_intr_in_desc,
973 NULL,
975 #define HS_FUNCTION_PRE_EP_ENTRIES 2
977 /* Maxpacket and other transfer characteristics vary by speed. */
978 static struct usb_endpoint_descriptor *
979 ep_desc(struct usb_gadget *g, struct usb_endpoint_descriptor *fs,
980 struct usb_endpoint_descriptor *hs)
982 if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
983 return hs;
984 return fs;
988 /* The CBI specification limits the serial string to 12 uppercase hexadecimal
989 * characters. */
990 static char manufacturer[64];
991 static char serial[13];
993 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
994 static struct usb_string strings[] = {
995 {STRING_MANUFACTURER, manufacturer},
996 {STRING_PRODUCT, longname},
997 {STRING_SERIAL, serial},
998 {STRING_CONFIG, "Self-powered"},
999 {STRING_INTERFACE, "Mass Storage"},
1003 static struct usb_gadget_strings stringtab = {
1004 .language = 0x0409, // en-us
1005 .strings = strings,
1010 * Config descriptors must agree with the code that sets configurations
1011 * and with code managing interfaces and their altsettings. They must
1012 * also handle different speeds and other-speed requests.
1014 static int populate_config_buf(struct usb_gadget *gadget,
1015 u8 *buf, u8 type, unsigned index)
1017 enum usb_device_speed speed = gadget->speed;
1018 int len;
1019 const struct usb_descriptor_header **function;
1021 if (index > 0)
1022 return -EINVAL;
1024 if (gadget_is_dualspeed(gadget) && type == USB_DT_OTHER_SPEED_CONFIG)
1025 speed = (USB_SPEED_FULL + USB_SPEED_HIGH) - speed;
1026 if (gadget_is_dualspeed(gadget) && speed == USB_SPEED_HIGH)
1027 function = hs_function;
1028 else
1029 function = fs_function;
1031 /* for now, don't advertise srp-only devices */
1032 if (!gadget_is_otg(gadget))
1033 function++;
1035 len = usb_gadget_config_buf(&config_desc, buf, EP0_BUFSIZE, function);
1036 ((struct usb_config_descriptor *) buf)->bDescriptorType = type;
1037 return len;
1041 /*-------------------------------------------------------------------------*/
1043 /* These routines may be called in process context or in_irq */
1045 /* Caller must hold fsg->lock */
1046 static void wakeup_thread(struct fsg_dev *fsg)
1048 /* Tell the main thread that something has happened */
1049 fsg->thread_wakeup_needed = 1;
1050 if (fsg->thread_task)
1051 wake_up_process(fsg->thread_task);
1055 static void raise_exception(struct fsg_dev *fsg, enum fsg_state new_state)
1057 unsigned long flags;
1059 /* Do nothing if a higher-priority exception is already in progress.
1060 * If a lower-or-equal priority exception is in progress, preempt it
1061 * and notify the main thread by sending it a signal. */
1062 spin_lock_irqsave(&fsg->lock, flags);
1063 if (fsg->state <= new_state) {
1064 fsg->exception_req_tag = fsg->ep0_req_tag;
1065 fsg->state = new_state;
1066 if (fsg->thread_task)
1067 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
1068 fsg->thread_task);
1070 spin_unlock_irqrestore(&fsg->lock, flags);
1074 /*-------------------------------------------------------------------------*/
1076 /* The disconnect callback and ep0 routines. These always run in_irq,
1077 * except that ep0_queue() is called in the main thread to acknowledge
1078 * completion of various requests: set config, set interface, and
1079 * Bulk-only device reset. */
1081 static void fsg_disconnect(struct usb_gadget *gadget)
1083 struct fsg_dev *fsg = get_gadget_data(gadget);
1085 DBG(fsg, "disconnect or port reset\n");
1086 raise_exception(fsg, FSG_STATE_DISCONNECT);
1090 static int ep0_queue(struct fsg_dev *fsg)
1092 int rc;
1094 rc = usb_ep_queue(fsg->ep0, fsg->ep0req, GFP_ATOMIC);
1095 if (rc != 0 && rc != -ESHUTDOWN) {
1097 /* We can't do much more than wait for a reset */
1098 WARN(fsg, "error in submission: %s --> %d\n",
1099 fsg->ep0->name, rc);
1101 return rc;
1104 static void ep0_complete(struct usb_ep *ep, struct usb_request *req)
1106 struct fsg_dev *fsg = ep->driver_data;
1108 if (req->actual > 0)
1109 dump_msg(fsg, fsg->ep0req_name, req->buf, req->actual);
1110 if (req->status || req->actual != req->length)
1111 DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
1112 req->status, req->actual, req->length);
1113 if (req->status == -ECONNRESET) // Request was cancelled
1114 usb_ep_fifo_flush(ep);
1116 if (req->status == 0 && req->context)
1117 ((fsg_routine_t) (req->context))(fsg);
1121 /*-------------------------------------------------------------------------*/
1123 /* Bulk and interrupt endpoint completion handlers.
1124 * These always run in_irq. */
1126 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
1128 struct fsg_dev *fsg = ep->driver_data;
1129 struct fsg_buffhd *bh = req->context;
1131 if (req->status || req->actual != req->length)
1132 DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
1133 req->status, req->actual, req->length);
1134 if (req->status == -ECONNRESET) // Request was cancelled
1135 usb_ep_fifo_flush(ep);
1137 /* Hold the lock while we update the request and buffer states */
1138 smp_wmb();
1139 spin_lock(&fsg->lock);
1140 bh->inreq_busy = 0;
1141 bh->state = BUF_STATE_EMPTY;
1142 wakeup_thread(fsg);
1143 spin_unlock(&fsg->lock);
1146 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
1148 struct fsg_dev *fsg = ep->driver_data;
1149 struct fsg_buffhd *bh = req->context;
1151 dump_msg(fsg, "bulk-out", req->buf, req->actual);
1152 if (req->status || req->actual != bh->bulk_out_intended_length)
1153 DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
1154 req->status, req->actual,
1155 bh->bulk_out_intended_length);
1156 if (req->status == -ECONNRESET) // Request was cancelled
1157 usb_ep_fifo_flush(ep);
1159 /* Hold the lock while we update the request and buffer states */
1160 smp_wmb();
1161 spin_lock(&fsg->lock);
1162 bh->outreq_busy = 0;
1163 bh->state = BUF_STATE_FULL;
1164 wakeup_thread(fsg);
1165 spin_unlock(&fsg->lock);
1169 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1170 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
1172 struct fsg_dev *fsg = ep->driver_data;
1173 struct fsg_buffhd *bh = req->context;
1175 if (req->status || req->actual != req->length)
1176 DBG(fsg, "%s --> %d, %u/%u\n", __FUNCTION__,
1177 req->status, req->actual, req->length);
1178 if (req->status == -ECONNRESET) // Request was cancelled
1179 usb_ep_fifo_flush(ep);
1181 /* Hold the lock while we update the request and buffer states */
1182 smp_wmb();
1183 spin_lock(&fsg->lock);
1184 fsg->intreq_busy = 0;
1185 bh->state = BUF_STATE_EMPTY;
1186 wakeup_thread(fsg);
1187 spin_unlock(&fsg->lock);
1190 #else
1191 static void intr_in_complete(struct usb_ep *ep, struct usb_request *req)
1193 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
1196 /*-------------------------------------------------------------------------*/
1198 /* Ep0 class-specific handlers. These always run in_irq. */
1200 #ifdef CONFIG_USB_FILE_STORAGE_TEST
1201 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1203 struct usb_request *req = fsg->ep0req;
1204 static u8 cbi_reset_cmnd[6] = {
1205 SC_SEND_DIAGNOSTIC, 4, 0xff, 0xff, 0xff, 0xff};
1207 /* Error in command transfer? */
1208 if (req->status || req->length != req->actual ||
1209 req->actual < 6 || req->actual > MAX_COMMAND_SIZE) {
1211 /* Not all controllers allow a protocol stall after
1212 * receiving control-out data, but we'll try anyway. */
1213 fsg_set_halt(fsg, fsg->ep0);
1214 return; // Wait for reset
1217 /* Is it the special reset command? */
1218 if (req->actual >= sizeof cbi_reset_cmnd &&
1219 memcmp(req->buf, cbi_reset_cmnd,
1220 sizeof cbi_reset_cmnd) == 0) {
1222 /* Raise an exception to stop the current operation
1223 * and reinitialize our state. */
1224 DBG(fsg, "cbi reset request\n");
1225 raise_exception(fsg, FSG_STATE_RESET);
1226 return;
1229 VDBG(fsg, "CB[I] accept device-specific command\n");
1230 spin_lock(&fsg->lock);
1232 /* Save the command for later */
1233 if (fsg->cbbuf_cmnd_size)
1234 WARN(fsg, "CB[I] overwriting previous command\n");
1235 fsg->cbbuf_cmnd_size = req->actual;
1236 memcpy(fsg->cbbuf_cmnd, req->buf, fsg->cbbuf_cmnd_size);
1238 wakeup_thread(fsg);
1239 spin_unlock(&fsg->lock);
1242 #else
1243 static void received_cbi_adsc(struct fsg_dev *fsg, struct fsg_buffhd *bh)
1245 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
1248 static int class_setup_req(struct fsg_dev *fsg,
1249 const struct usb_ctrlrequest *ctrl)
1251 struct usb_request *req = fsg->ep0req;
1252 int value = -EOPNOTSUPP;
1253 u16 w_index = le16_to_cpu(ctrl->wIndex);
1254 u16 w_value = le16_to_cpu(ctrl->wValue);
1255 u16 w_length = le16_to_cpu(ctrl->wLength);
1257 if (!fsg->config)
1258 return value;
1260 /* Handle Bulk-only class-specific requests */
1261 if (transport_is_bbb()) {
1262 switch (ctrl->bRequest) {
1264 case USB_BULK_RESET_REQUEST:
1265 if (ctrl->bRequestType != (USB_DIR_OUT |
1266 USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1267 break;
1268 if (w_index != 0 || w_value != 0) {
1269 value = -EDOM;
1270 break;
1273 /* Raise an exception to stop the current operation
1274 * and reinitialize our state. */
1275 DBG(fsg, "bulk reset request\n");
1276 raise_exception(fsg, FSG_STATE_RESET);
1277 value = DELAYED_STATUS;
1278 break;
1280 case USB_BULK_GET_MAX_LUN_REQUEST:
1281 if (ctrl->bRequestType != (USB_DIR_IN |
1282 USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1283 break;
1284 if (w_index != 0 || w_value != 0) {
1285 value = -EDOM;
1286 break;
1288 VDBG(fsg, "get max LUN\n");
1289 *(u8 *) req->buf = fsg->nluns - 1;
1290 value = 1;
1291 break;
1295 /* Handle CBI class-specific requests */
1296 else {
1297 switch (ctrl->bRequest) {
1299 case USB_CBI_ADSC_REQUEST:
1300 if (ctrl->bRequestType != (USB_DIR_OUT |
1301 USB_TYPE_CLASS | USB_RECIP_INTERFACE))
1302 break;
1303 if (w_index != 0 || w_value != 0) {
1304 value = -EDOM;
1305 break;
1307 if (w_length > MAX_COMMAND_SIZE) {
1308 value = -EOVERFLOW;
1309 break;
1311 value = w_length;
1312 fsg->ep0req->context = received_cbi_adsc;
1313 break;
1317 if (value == -EOPNOTSUPP)
1318 VDBG(fsg,
1319 "unknown class-specific control req "
1320 "%02x.%02x v%04x i%04x l%u\n",
1321 ctrl->bRequestType, ctrl->bRequest,
1322 le16_to_cpu(ctrl->wValue), w_index, w_length);
1323 return value;
1327 /*-------------------------------------------------------------------------*/
1329 /* Ep0 standard request handlers. These always run in_irq. */
1331 static int standard_setup_req(struct fsg_dev *fsg,
1332 const struct usb_ctrlrequest *ctrl)
1334 struct usb_request *req = fsg->ep0req;
1335 int value = -EOPNOTSUPP;
1336 u16 w_index = le16_to_cpu(ctrl->wIndex);
1337 u16 w_value = le16_to_cpu(ctrl->wValue);
1339 /* Usually this just stores reply data in the pre-allocated ep0 buffer,
1340 * but config change events will also reconfigure hardware. */
1341 switch (ctrl->bRequest) {
1343 case USB_REQ_GET_DESCRIPTOR:
1344 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1345 USB_RECIP_DEVICE))
1346 break;
1347 switch (w_value >> 8) {
1349 case USB_DT_DEVICE:
1350 VDBG(fsg, "get device descriptor\n");
1351 value = sizeof device_desc;
1352 memcpy(req->buf, &device_desc, value);
1353 break;
1354 case USB_DT_DEVICE_QUALIFIER:
1355 VDBG(fsg, "get device qualifier\n");
1356 if (!gadget_is_dualspeed(fsg->gadget))
1357 break;
1358 value = sizeof dev_qualifier;
1359 memcpy(req->buf, &dev_qualifier, value);
1360 break;
1362 case USB_DT_OTHER_SPEED_CONFIG:
1363 VDBG(fsg, "get other-speed config descriptor\n");
1364 if (!gadget_is_dualspeed(fsg->gadget))
1365 break;
1366 goto get_config;
1367 case USB_DT_CONFIG:
1368 VDBG(fsg, "get configuration descriptor\n");
1369 get_config:
1370 value = populate_config_buf(fsg->gadget,
1371 req->buf,
1372 w_value >> 8,
1373 w_value & 0xff);
1374 break;
1376 case USB_DT_STRING:
1377 VDBG(fsg, "get string descriptor\n");
1379 /* wIndex == language code */
1380 value = usb_gadget_get_string(&stringtab,
1381 w_value & 0xff, req->buf);
1382 break;
1384 break;
1386 /* One config, two speeds */
1387 case USB_REQ_SET_CONFIGURATION:
1388 if (ctrl->bRequestType != (USB_DIR_OUT | USB_TYPE_STANDARD |
1389 USB_RECIP_DEVICE))
1390 break;
1391 VDBG(fsg, "set configuration\n");
1392 if (w_value == CONFIG_VALUE || w_value == 0) {
1393 fsg->new_config = w_value;
1395 /* Raise an exception to wipe out previous transaction
1396 * state (queued bufs, etc) and set the new config. */
1397 raise_exception(fsg, FSG_STATE_CONFIG_CHANGE);
1398 value = DELAYED_STATUS;
1400 break;
1401 case USB_REQ_GET_CONFIGURATION:
1402 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1403 USB_RECIP_DEVICE))
1404 break;
1405 VDBG(fsg, "get configuration\n");
1406 *(u8 *) req->buf = fsg->config;
1407 value = 1;
1408 break;
1410 case USB_REQ_SET_INTERFACE:
1411 if (ctrl->bRequestType != (USB_DIR_OUT| USB_TYPE_STANDARD |
1412 USB_RECIP_INTERFACE))
1413 break;
1414 if (fsg->config && w_index == 0) {
1416 /* Raise an exception to wipe out previous transaction
1417 * state (queued bufs, etc) and install the new
1418 * interface altsetting. */
1419 raise_exception(fsg, FSG_STATE_INTERFACE_CHANGE);
1420 value = DELAYED_STATUS;
1422 break;
1423 case USB_REQ_GET_INTERFACE:
1424 if (ctrl->bRequestType != (USB_DIR_IN | USB_TYPE_STANDARD |
1425 USB_RECIP_INTERFACE))
1426 break;
1427 if (!fsg->config)
1428 break;
1429 if (w_index != 0) {
1430 value = -EDOM;
1431 break;
1433 VDBG(fsg, "get interface\n");
1434 *(u8 *) req->buf = 0;
1435 value = 1;
1436 break;
1438 default:
1439 VDBG(fsg,
1440 "unknown control req %02x.%02x v%04x i%04x l%u\n",
1441 ctrl->bRequestType, ctrl->bRequest,
1442 w_value, w_index, le16_to_cpu(ctrl->wLength));
1445 return value;
1449 static int fsg_setup(struct usb_gadget *gadget,
1450 const struct usb_ctrlrequest *ctrl)
1452 struct fsg_dev *fsg = get_gadget_data(gadget);
1453 int rc;
1454 int w_length = le16_to_cpu(ctrl->wLength);
1456 ++fsg->ep0_req_tag; // Record arrival of a new request
1457 fsg->ep0req->context = NULL;
1458 fsg->ep0req->length = 0;
1459 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
1461 if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS)
1462 rc = class_setup_req(fsg, ctrl);
1463 else
1464 rc = standard_setup_req(fsg, ctrl);
1466 /* Respond with data/status or defer until later? */
1467 if (rc >= 0 && rc != DELAYED_STATUS) {
1468 rc = min(rc, w_length);
1469 fsg->ep0req->length = rc;
1470 fsg->ep0req->zero = rc < w_length;
1471 fsg->ep0req_name = (ctrl->bRequestType & USB_DIR_IN ?
1472 "ep0-in" : "ep0-out");
1473 rc = ep0_queue(fsg);
1476 /* Device either stalls (rc < 0) or reports success */
1477 return rc;
1481 /*-------------------------------------------------------------------------*/
1483 /* All the following routines run in process context */
1486 /* Use this for bulk or interrupt transfers, not ep0 */
1487 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
1488 struct usb_request *req, int *pbusy,
1489 enum fsg_buffer_state *state)
1491 int rc;
1493 if (ep == fsg->bulk_in)
1494 dump_msg(fsg, "bulk-in", req->buf, req->length);
1495 else if (ep == fsg->intr_in)
1496 dump_msg(fsg, "intr-in", req->buf, req->length);
1498 spin_lock_irq(&fsg->lock);
1499 *pbusy = 1;
1500 *state = BUF_STATE_BUSY;
1501 spin_unlock_irq(&fsg->lock);
1502 rc = usb_ep_queue(ep, req, GFP_KERNEL);
1503 if (rc != 0) {
1504 *pbusy = 0;
1505 *state = BUF_STATE_EMPTY;
1507 /* We can't do much more than wait for a reset */
1509 /* Note: currently the net2280 driver fails zero-length
1510 * submissions if DMA is enabled. */
1511 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
1512 req->length == 0))
1513 WARN(fsg, "error in submission: %s --> %d\n",
1514 ep->name, rc);
1519 static int sleep_thread(struct fsg_dev *fsg)
1521 int rc = 0;
1523 /* Wait until a signal arrives or we are woken up */
1524 for (;;) {
1525 try_to_freeze();
1526 set_current_state(TASK_INTERRUPTIBLE);
1527 if (signal_pending(current)) {
1528 rc = -EINTR;
1529 break;
1531 if (fsg->thread_wakeup_needed)
1532 break;
1533 schedule();
1535 __set_current_state(TASK_RUNNING);
1536 fsg->thread_wakeup_needed = 0;
1537 return rc;
1541 /*-------------------------------------------------------------------------*/
1543 static int do_read(struct fsg_dev *fsg)
1545 struct lun *curlun = fsg->curlun;
1546 u32 lba;
1547 struct fsg_buffhd *bh;
1548 int rc;
1549 u32 amount_left;
1550 loff_t file_offset, file_offset_tmp;
1551 unsigned int amount;
1552 unsigned int partial_page;
1553 ssize_t nread;
1555 /* Get the starting Logical Block Address and check that it's
1556 * not too big */
1557 if (fsg->cmnd[0] == SC_READ_6)
1558 lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
1559 else {
1560 lba = get_be32(&fsg->cmnd[2]);
1562 /* We allow DPO (Disable Page Out = don't save data in the
1563 * cache) and FUA (Force Unit Access = don't read from the
1564 * cache), but we don't implement them. */
1565 if ((fsg->cmnd[1] & ~0x18) != 0) {
1566 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1567 return -EINVAL;
1570 if (lba >= curlun->num_sectors) {
1571 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1572 return -EINVAL;
1574 file_offset = ((loff_t) lba) << 9;
1576 /* Carry out the file reads */
1577 amount_left = fsg->data_size_from_cmnd;
1578 if (unlikely(amount_left == 0))
1579 return -EIO; // No default reply
1581 for (;;) {
1583 /* Figure out how much we need to read:
1584 * Try to read the remaining amount.
1585 * But don't read more than the buffer size.
1586 * And don't try to read past the end of the file.
1587 * Finally, if we're not at a page boundary, don't read past
1588 * the next page.
1589 * If this means reading 0 then we were asked to read past
1590 * the end of file. */
1591 amount = min((unsigned int) amount_left, mod_data.buflen);
1592 amount = min((loff_t) amount,
1593 curlun->file_length - file_offset);
1594 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
1595 if (partial_page > 0)
1596 amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
1597 partial_page);
1599 /* Wait for the next buffer to become available */
1600 bh = fsg->next_buffhd_to_fill;
1601 while (bh->state != BUF_STATE_EMPTY) {
1602 rc = sleep_thread(fsg);
1603 if (rc)
1604 return rc;
1607 /* If we were asked to read past the end of file,
1608 * end with an empty buffer. */
1609 if (amount == 0) {
1610 curlun->sense_data =
1611 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1612 curlun->sense_data_info = file_offset >> 9;
1613 curlun->info_valid = 1;
1614 bh->inreq->length = 0;
1615 bh->state = BUF_STATE_FULL;
1616 break;
1619 /* Perform the read */
1620 file_offset_tmp = file_offset;
1621 nread = vfs_read(curlun->filp,
1622 (char __user *) bh->buf,
1623 amount, &file_offset_tmp);
1624 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1625 (unsigned long long) file_offset,
1626 (int) nread);
1627 if (signal_pending(current))
1628 return -EINTR;
1630 if (nread < 0) {
1631 LDBG(curlun, "error in file read: %d\n",
1632 (int) nread);
1633 nread = 0;
1634 } else if (nread < amount) {
1635 LDBG(curlun, "partial file read: %d/%u\n",
1636 (int) nread, amount);
1637 nread -= (nread & 511); // Round down to a block
1639 file_offset += nread;
1640 amount_left -= nread;
1641 fsg->residue -= nread;
1642 bh->inreq->length = nread;
1643 bh->state = BUF_STATE_FULL;
1645 /* If an error occurred, report it and its position */
1646 if (nread < amount) {
1647 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1648 curlun->sense_data_info = file_offset >> 9;
1649 curlun->info_valid = 1;
1650 break;
1653 if (amount_left == 0)
1654 break; // No more left to read
1656 /* Send this buffer and go read some more */
1657 bh->inreq->zero = 0;
1658 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1659 &bh->inreq_busy, &bh->state);
1660 fsg->next_buffhd_to_fill = bh->next;
1663 return -EIO; // No default reply
1667 /*-------------------------------------------------------------------------*/
1669 static int do_write(struct fsg_dev *fsg)
1671 struct lun *curlun = fsg->curlun;
1672 u32 lba;
1673 struct fsg_buffhd *bh;
1674 int get_some_more;
1675 u32 amount_left_to_req, amount_left_to_write;
1676 loff_t usb_offset, file_offset, file_offset_tmp;
1677 unsigned int amount;
1678 unsigned int partial_page;
1679 ssize_t nwritten;
1680 int rc;
1682 if (curlun->ro) {
1683 curlun->sense_data = SS_WRITE_PROTECTED;
1684 return -EINVAL;
1686 curlun->filp->f_flags &= ~O_SYNC; // Default is not to wait
1688 /* Get the starting Logical Block Address and check that it's
1689 * not too big */
1690 if (fsg->cmnd[0] == SC_WRITE_6)
1691 lba = (fsg->cmnd[1] << 16) | get_be16(&fsg->cmnd[2]);
1692 else {
1693 lba = get_be32(&fsg->cmnd[2]);
1695 /* We allow DPO (Disable Page Out = don't save data in the
1696 * cache) and FUA (Force Unit Access = write directly to the
1697 * medium). We don't implement DPO; we implement FUA by
1698 * performing synchronous output. */
1699 if ((fsg->cmnd[1] & ~0x18) != 0) {
1700 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1701 return -EINVAL;
1703 if (fsg->cmnd[1] & 0x08) // FUA
1704 curlun->filp->f_flags |= O_SYNC;
1706 if (lba >= curlun->num_sectors) {
1707 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1708 return -EINVAL;
1711 /* Carry out the file writes */
1712 get_some_more = 1;
1713 file_offset = usb_offset = ((loff_t) lba) << 9;
1714 amount_left_to_req = amount_left_to_write = fsg->data_size_from_cmnd;
1716 while (amount_left_to_write > 0) {
1718 /* Queue a request for more data from the host */
1719 bh = fsg->next_buffhd_to_fill;
1720 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
1722 /* Figure out how much we want to get:
1723 * Try to get the remaining amount.
1724 * But don't get more than the buffer size.
1725 * And don't try to go past the end of the file.
1726 * If we're not at a page boundary,
1727 * don't go past the next page.
1728 * If this means getting 0, then we were asked
1729 * to write past the end of file.
1730 * Finally, round down to a block boundary. */
1731 amount = min(amount_left_to_req, mod_data.buflen);
1732 amount = min((loff_t) amount, curlun->file_length -
1733 usb_offset);
1734 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
1735 if (partial_page > 0)
1736 amount = min(amount,
1737 (unsigned int) PAGE_CACHE_SIZE - partial_page);
1739 if (amount == 0) {
1740 get_some_more = 0;
1741 curlun->sense_data =
1742 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1743 curlun->sense_data_info = usb_offset >> 9;
1744 curlun->info_valid = 1;
1745 continue;
1747 amount -= (amount & 511);
1748 if (amount == 0) {
1750 /* Why were we were asked to transfer a
1751 * partial block? */
1752 get_some_more = 0;
1753 continue;
1756 /* Get the next buffer */
1757 usb_offset += amount;
1758 fsg->usb_amount_left -= amount;
1759 amount_left_to_req -= amount;
1760 if (amount_left_to_req == 0)
1761 get_some_more = 0;
1763 /* amount is always divisible by 512, hence by
1764 * the bulk-out maxpacket size */
1765 bh->outreq->length = bh->bulk_out_intended_length =
1766 amount;
1767 bh->outreq->short_not_ok = 1;
1768 start_transfer(fsg, fsg->bulk_out, bh->outreq,
1769 &bh->outreq_busy, &bh->state);
1770 fsg->next_buffhd_to_fill = bh->next;
1771 continue;
1774 /* Write the received data to the backing file */
1775 bh = fsg->next_buffhd_to_drain;
1776 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
1777 break; // We stopped early
1778 if (bh->state == BUF_STATE_FULL) {
1779 smp_rmb();
1780 fsg->next_buffhd_to_drain = bh->next;
1781 bh->state = BUF_STATE_EMPTY;
1783 /* Did something go wrong with the transfer? */
1784 if (bh->outreq->status != 0) {
1785 curlun->sense_data = SS_COMMUNICATION_FAILURE;
1786 curlun->sense_data_info = file_offset >> 9;
1787 curlun->info_valid = 1;
1788 break;
1791 amount = bh->outreq->actual;
1792 if (curlun->file_length - file_offset < amount) {
1793 LERROR(curlun,
1794 "write %u @ %llu beyond end %llu\n",
1795 amount, (unsigned long long) file_offset,
1796 (unsigned long long) curlun->file_length);
1797 amount = curlun->file_length - file_offset;
1800 /* Perform the write */
1801 file_offset_tmp = file_offset;
1802 nwritten = vfs_write(curlun->filp,
1803 (char __user *) bh->buf,
1804 amount, &file_offset_tmp);
1805 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1806 (unsigned long long) file_offset,
1807 (int) nwritten);
1808 if (signal_pending(current))
1809 return -EINTR; // Interrupted!
1811 if (nwritten < 0) {
1812 LDBG(curlun, "error in file write: %d\n",
1813 (int) nwritten);
1814 nwritten = 0;
1815 } else if (nwritten < amount) {
1816 LDBG(curlun, "partial file write: %d/%u\n",
1817 (int) nwritten, amount);
1818 nwritten -= (nwritten & 511);
1819 // Round down to a block
1821 file_offset += nwritten;
1822 amount_left_to_write -= nwritten;
1823 fsg->residue -= nwritten;
1825 /* If an error occurred, report it and its position */
1826 if (nwritten < amount) {
1827 curlun->sense_data = SS_WRITE_ERROR;
1828 curlun->sense_data_info = file_offset >> 9;
1829 curlun->info_valid = 1;
1830 break;
1833 /* Did the host decide to stop early? */
1834 if (bh->outreq->actual != bh->outreq->length) {
1835 fsg->short_packet_received = 1;
1836 break;
1838 continue;
1841 /* Wait for something to happen */
1842 rc = sleep_thread(fsg);
1843 if (rc)
1844 return rc;
1847 return -EIO; // No default reply
1851 /*-------------------------------------------------------------------------*/
1853 /* Sync the file data, don't bother with the metadata.
1854 * This code was copied from fs/buffer.c:sys_fdatasync(). */
1855 static int fsync_sub(struct lun *curlun)
1857 struct file *filp = curlun->filp;
1858 struct inode *inode;
1859 int rc, err;
1861 if (curlun->ro || !filp)
1862 return 0;
1863 if (!filp->f_op->fsync)
1864 return -EINVAL;
1866 inode = filp->f_path.dentry->d_inode;
1867 mutex_lock(&inode->i_mutex);
1868 rc = filemap_fdatawrite(inode->i_mapping);
1869 err = filp->f_op->fsync(filp, filp->f_path.dentry, 1);
1870 if (!rc)
1871 rc = err;
1872 err = filemap_fdatawait(inode->i_mapping);
1873 if (!rc)
1874 rc = err;
1875 mutex_unlock(&inode->i_mutex);
1876 VLDBG(curlun, "fdatasync -> %d\n", rc);
1877 return rc;
1880 static void fsync_all(struct fsg_dev *fsg)
1882 int i;
1884 for (i = 0; i < fsg->nluns; ++i)
1885 fsync_sub(&fsg->luns[i]);
1888 static int do_synchronize_cache(struct fsg_dev *fsg)
1890 struct lun *curlun = fsg->curlun;
1891 int rc;
1893 /* We ignore the requested LBA and write out all file's
1894 * dirty data buffers. */
1895 rc = fsync_sub(curlun);
1896 if (rc)
1897 curlun->sense_data = SS_WRITE_ERROR;
1898 return 0;
1902 /*-------------------------------------------------------------------------*/
1904 static void invalidate_sub(struct lun *curlun)
1906 struct file *filp = curlun->filp;
1907 struct inode *inode = filp->f_path.dentry->d_inode;
1908 unsigned long rc;
1910 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1911 VLDBG(curlun, "invalidate_inode_pages -> %ld\n", rc);
1914 static int do_verify(struct fsg_dev *fsg)
1916 struct lun *curlun = fsg->curlun;
1917 u32 lba;
1918 u32 verification_length;
1919 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill;
1920 loff_t file_offset, file_offset_tmp;
1921 u32 amount_left;
1922 unsigned int amount;
1923 ssize_t nread;
1925 /* Get the starting Logical Block Address and check that it's
1926 * not too big */
1927 lba = get_be32(&fsg->cmnd[2]);
1928 if (lba >= curlun->num_sectors) {
1929 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1930 return -EINVAL;
1933 /* We allow DPO (Disable Page Out = don't save data in the
1934 * cache) but we don't implement it. */
1935 if ((fsg->cmnd[1] & ~0x10) != 0) {
1936 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1937 return -EINVAL;
1940 verification_length = get_be16(&fsg->cmnd[7]);
1941 if (unlikely(verification_length == 0))
1942 return -EIO; // No default reply
1944 /* Prepare to carry out the file verify */
1945 amount_left = verification_length << 9;
1946 file_offset = ((loff_t) lba) << 9;
1948 /* Write out all the dirty buffers before invalidating them */
1949 fsync_sub(curlun);
1950 if (signal_pending(current))
1951 return -EINTR;
1953 invalidate_sub(curlun);
1954 if (signal_pending(current))
1955 return -EINTR;
1957 /* Just try to read the requested blocks */
1958 while (amount_left > 0) {
1960 /* Figure out how much we need to read:
1961 * Try to read the remaining amount, but not more than
1962 * the buffer size.
1963 * And don't try to read past the end of the file.
1964 * If this means reading 0 then we were asked to read
1965 * past the end of file. */
1966 amount = min((unsigned int) amount_left, mod_data.buflen);
1967 amount = min((loff_t) amount,
1968 curlun->file_length - file_offset);
1969 if (amount == 0) {
1970 curlun->sense_data =
1971 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1972 curlun->sense_data_info = file_offset >> 9;
1973 curlun->info_valid = 1;
1974 break;
1977 /* Perform the read */
1978 file_offset_tmp = file_offset;
1979 nread = vfs_read(curlun->filp,
1980 (char __user *) bh->buf,
1981 amount, &file_offset_tmp);
1982 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1983 (unsigned long long) file_offset,
1984 (int) nread);
1985 if (signal_pending(current))
1986 return -EINTR;
1988 if (nread < 0) {
1989 LDBG(curlun, "error in file verify: %d\n",
1990 (int) nread);
1991 nread = 0;
1992 } else if (nread < amount) {
1993 LDBG(curlun, "partial file verify: %d/%u\n",
1994 (int) nread, amount);
1995 nread -= (nread & 511); // Round down to a sector
1997 if (nread == 0) {
1998 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1999 curlun->sense_data_info = file_offset >> 9;
2000 curlun->info_valid = 1;
2001 break;
2003 file_offset += nread;
2004 amount_left -= nread;
2006 return 0;
2010 /*-------------------------------------------------------------------------*/
2012 static int do_inquiry(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2014 u8 *buf = (u8 *) bh->buf;
2016 static char vendor_id[] = "Linux ";
2017 static char product_id[] = "File-Stor Gadget";
2019 if (!fsg->curlun) { // Unsupported LUNs are okay
2020 fsg->bad_lun_okay = 1;
2021 memset(buf, 0, 36);
2022 buf[0] = 0x7f; // Unsupported, no device-type
2023 return 36;
2026 memset(buf, 0, 8); // Non-removable, direct-access device
2027 if (mod_data.removable)
2028 buf[1] = 0x80;
2029 buf[2] = 2; // ANSI SCSI level 2
2030 buf[3] = 2; // SCSI-2 INQUIRY data format
2031 buf[4] = 31; // Additional length
2032 // No special options
2033 sprintf(buf + 8, "%-8s%-16s%04x", vendor_id, product_id,
2034 mod_data.release);
2035 return 36;
2039 static int do_request_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2041 struct lun *curlun = fsg->curlun;
2042 u8 *buf = (u8 *) bh->buf;
2043 u32 sd, sdinfo;
2044 int valid;
2047 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
2049 * If a REQUEST SENSE command is received from an initiator
2050 * with a pending unit attention condition (before the target
2051 * generates the contingent allegiance condition), then the
2052 * target shall either:
2053 * a) report any pending sense data and preserve the unit
2054 * attention condition on the logical unit, or,
2055 * b) report the unit attention condition, may discard any
2056 * pending sense data, and clear the unit attention
2057 * condition on the logical unit for that initiator.
2059 * FSG normally uses option a); enable this code to use option b).
2061 #if 0
2062 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
2063 curlun->sense_data = curlun->unit_attention_data;
2064 curlun->unit_attention_data = SS_NO_SENSE;
2066 #endif
2068 if (!curlun) { // Unsupported LUNs are okay
2069 fsg->bad_lun_okay = 1;
2070 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2071 sdinfo = 0;
2072 valid = 0;
2073 } else {
2074 sd = curlun->sense_data;
2075 sdinfo = curlun->sense_data_info;
2076 valid = curlun->info_valid << 7;
2077 curlun->sense_data = SS_NO_SENSE;
2078 curlun->sense_data_info = 0;
2079 curlun->info_valid = 0;
2082 memset(buf, 0, 18);
2083 buf[0] = valid | 0x70; // Valid, current error
2084 buf[2] = SK(sd);
2085 put_be32(&buf[3], sdinfo); // Sense information
2086 buf[7] = 18 - 8; // Additional sense length
2087 buf[12] = ASC(sd);
2088 buf[13] = ASCQ(sd);
2089 return 18;
2093 static int do_read_capacity(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2095 struct lun *curlun = fsg->curlun;
2096 u32 lba = get_be32(&fsg->cmnd[2]);
2097 int pmi = fsg->cmnd[8];
2098 u8 *buf = (u8 *) bh->buf;
2100 /* Check the PMI and LBA fields */
2101 if (pmi > 1 || (pmi == 0 && lba != 0)) {
2102 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2103 return -EINVAL;
2106 put_be32(&buf[0], curlun->num_sectors - 1); // Max logical block
2107 put_be32(&buf[4], 512); // Block length
2108 return 8;
2112 static int do_mode_sense(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2114 struct lun *curlun = fsg->curlun;
2115 int mscmnd = fsg->cmnd[0];
2116 u8 *buf = (u8 *) bh->buf;
2117 u8 *buf0 = buf;
2118 int pc, page_code;
2119 int changeable_values, all_pages;
2120 int valid_page = 0;
2121 int len, limit;
2123 if ((fsg->cmnd[1] & ~0x08) != 0) { // Mask away DBD
2124 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2125 return -EINVAL;
2127 pc = fsg->cmnd[2] >> 6;
2128 page_code = fsg->cmnd[2] & 0x3f;
2129 if (pc == 3) {
2130 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
2131 return -EINVAL;
2133 changeable_values = (pc == 1);
2134 all_pages = (page_code == 0x3f);
2136 /* Write the mode parameter header. Fixed values are: default
2137 * medium type, no cache control (DPOFUA), and no block descriptors.
2138 * The only variable value is the WriteProtect bit. We will fill in
2139 * the mode data length later. */
2140 memset(buf, 0, 8);
2141 if (mscmnd == SC_MODE_SENSE_6) {
2142 buf[2] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
2143 buf += 4;
2144 limit = 255;
2145 } else { // SC_MODE_SENSE_10
2146 buf[3] = (curlun->ro ? 0x80 : 0x00); // WP, DPOFUA
2147 buf += 8;
2148 limit = 65535; // Should really be mod_data.buflen
2151 /* No block descriptors */
2153 /* The mode pages, in numerical order. The only page we support
2154 * is the Caching page. */
2155 if (page_code == 0x08 || all_pages) {
2156 valid_page = 1;
2157 buf[0] = 0x08; // Page code
2158 buf[1] = 10; // Page length
2159 memset(buf+2, 0, 10); // None of the fields are changeable
2161 if (!changeable_values) {
2162 buf[2] = 0x04; // Write cache enable,
2163 // Read cache not disabled
2164 // No cache retention priorities
2165 put_be16(&buf[4], 0xffff); // Don't disable prefetch
2166 // Minimum prefetch = 0
2167 put_be16(&buf[8], 0xffff); // Maximum prefetch
2168 put_be16(&buf[10], 0xffff); // Maximum prefetch ceiling
2170 buf += 12;
2173 /* Check that a valid page was requested and the mode data length
2174 * isn't too long. */
2175 len = buf - buf0;
2176 if (!valid_page || len > limit) {
2177 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2178 return -EINVAL;
2181 /* Store the mode data length */
2182 if (mscmnd == SC_MODE_SENSE_6)
2183 buf0[0] = len - 1;
2184 else
2185 put_be16(buf0, len - 2);
2186 return len;
2190 static int do_start_stop(struct fsg_dev *fsg)
2192 struct lun *curlun = fsg->curlun;
2193 int loej, start;
2195 if (!mod_data.removable) {
2196 curlun->sense_data = SS_INVALID_COMMAND;
2197 return -EINVAL;
2200 // int immed = fsg->cmnd[1] & 0x01;
2201 loej = fsg->cmnd[4] & 0x02;
2202 start = fsg->cmnd[4] & 0x01;
2204 #ifdef CONFIG_USB_FILE_STORAGE_TEST
2205 if ((fsg->cmnd[1] & ~0x01) != 0 || // Mask away Immed
2206 (fsg->cmnd[4] & ~0x03) != 0) { // Mask LoEj, Start
2207 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2208 return -EINVAL;
2211 if (!start) {
2213 /* Are we allowed to unload the media? */
2214 if (curlun->prevent_medium_removal) {
2215 LDBG(curlun, "unload attempt prevented\n");
2216 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
2217 return -EINVAL;
2219 if (loej) { // Simulate an unload/eject
2220 up_read(&fsg->filesem);
2221 down_write(&fsg->filesem);
2222 close_backing_file(curlun);
2223 up_write(&fsg->filesem);
2224 down_read(&fsg->filesem);
2226 } else {
2228 /* Our emulation doesn't support mounting; the medium is
2229 * available for use as soon as it is loaded. */
2230 if (!backing_file_is_open(curlun)) {
2231 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2232 return -EINVAL;
2235 #endif
2236 return 0;
2240 static int do_prevent_allow(struct fsg_dev *fsg)
2242 struct lun *curlun = fsg->curlun;
2243 int prevent;
2245 if (!mod_data.removable) {
2246 curlun->sense_data = SS_INVALID_COMMAND;
2247 return -EINVAL;
2250 prevent = fsg->cmnd[4] & 0x01;
2251 if ((fsg->cmnd[4] & ~0x01) != 0) { // Mask away Prevent
2252 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2253 return -EINVAL;
2256 if (curlun->prevent_medium_removal && !prevent)
2257 fsync_sub(curlun);
2258 curlun->prevent_medium_removal = prevent;
2259 return 0;
2263 static int do_read_format_capacities(struct fsg_dev *fsg,
2264 struct fsg_buffhd *bh)
2266 struct lun *curlun = fsg->curlun;
2267 u8 *buf = (u8 *) bh->buf;
2269 buf[0] = buf[1] = buf[2] = 0;
2270 buf[3] = 8; // Only the Current/Maximum Capacity Descriptor
2271 buf += 4;
2273 put_be32(&buf[0], curlun->num_sectors); // Number of blocks
2274 put_be32(&buf[4], 512); // Block length
2275 buf[4] = 0x02; // Current capacity
2276 return 12;
2280 static int do_mode_select(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2282 struct lun *curlun = fsg->curlun;
2284 /* We don't support MODE SELECT */
2285 curlun->sense_data = SS_INVALID_COMMAND;
2286 return -EINVAL;
2290 /*-------------------------------------------------------------------------*/
2292 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
2294 int rc;
2296 rc = fsg_set_halt(fsg, fsg->bulk_in);
2297 if (rc == -EAGAIN)
2298 VDBG(fsg, "delayed bulk-in endpoint halt\n");
2299 while (rc != 0) {
2300 if (rc != -EAGAIN) {
2301 WARN(fsg, "usb_ep_set_halt -> %d\n", rc);
2302 rc = 0;
2303 break;
2306 /* Wait for a short time and then try again */
2307 if (msleep_interruptible(100) != 0)
2308 return -EINTR;
2309 rc = usb_ep_set_halt(fsg->bulk_in);
2311 return rc;
2314 static int pad_with_zeros(struct fsg_dev *fsg)
2316 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill;
2317 u32 nkeep = bh->inreq->length;
2318 u32 nsend;
2319 int rc;
2321 bh->state = BUF_STATE_EMPTY; // For the first iteration
2322 fsg->usb_amount_left = nkeep + fsg->residue;
2323 while (fsg->usb_amount_left > 0) {
2325 /* Wait for the next buffer to be free */
2326 while (bh->state != BUF_STATE_EMPTY) {
2327 rc = sleep_thread(fsg);
2328 if (rc)
2329 return rc;
2332 nsend = min(fsg->usb_amount_left, (u32) mod_data.buflen);
2333 memset(bh->buf + nkeep, 0, nsend - nkeep);
2334 bh->inreq->length = nsend;
2335 bh->inreq->zero = 0;
2336 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2337 &bh->inreq_busy, &bh->state);
2338 bh = fsg->next_buffhd_to_fill = bh->next;
2339 fsg->usb_amount_left -= nsend;
2340 nkeep = 0;
2342 return 0;
2345 static int throw_away_data(struct fsg_dev *fsg)
2347 struct fsg_buffhd *bh;
2348 u32 amount;
2349 int rc;
2351 while ((bh = fsg->next_buffhd_to_drain)->state != BUF_STATE_EMPTY ||
2352 fsg->usb_amount_left > 0) {
2354 /* Throw away the data in a filled buffer */
2355 if (bh->state == BUF_STATE_FULL) {
2356 smp_rmb();
2357 bh->state = BUF_STATE_EMPTY;
2358 fsg->next_buffhd_to_drain = bh->next;
2360 /* A short packet or an error ends everything */
2361 if (bh->outreq->actual != bh->outreq->length ||
2362 bh->outreq->status != 0) {
2363 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2364 return -EINTR;
2366 continue;
2369 /* Try to submit another request if we need one */
2370 bh = fsg->next_buffhd_to_fill;
2371 if (bh->state == BUF_STATE_EMPTY && fsg->usb_amount_left > 0) {
2372 amount = min(fsg->usb_amount_left,
2373 (u32) mod_data.buflen);
2375 /* amount is always divisible by 512, hence by
2376 * the bulk-out maxpacket size */
2377 bh->outreq->length = bh->bulk_out_intended_length =
2378 amount;
2379 bh->outreq->short_not_ok = 1;
2380 start_transfer(fsg, fsg->bulk_out, bh->outreq,
2381 &bh->outreq_busy, &bh->state);
2382 fsg->next_buffhd_to_fill = bh->next;
2383 fsg->usb_amount_left -= amount;
2384 continue;
2387 /* Otherwise wait for something to happen */
2388 rc = sleep_thread(fsg);
2389 if (rc)
2390 return rc;
2392 return 0;
2396 static int finish_reply(struct fsg_dev *fsg)
2398 struct fsg_buffhd *bh = fsg->next_buffhd_to_fill;
2399 int rc = 0;
2401 switch (fsg->data_dir) {
2402 case DATA_DIR_NONE:
2403 break; // Nothing to send
2405 /* If we don't know whether the host wants to read or write,
2406 * this must be CB or CBI with an unknown command. We mustn't
2407 * try to send or receive any data. So stall both bulk pipes
2408 * if we can and wait for a reset. */
2409 case DATA_DIR_UNKNOWN:
2410 if (mod_data.can_stall) {
2411 fsg_set_halt(fsg, fsg->bulk_out);
2412 rc = halt_bulk_in_endpoint(fsg);
2414 break;
2416 /* All but the last buffer of data must have already been sent */
2417 case DATA_DIR_TO_HOST:
2418 if (fsg->data_size == 0)
2419 ; // Nothing to send
2421 /* If there's no residue, simply send the last buffer */
2422 else if (fsg->residue == 0) {
2423 bh->inreq->zero = 0;
2424 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2425 &bh->inreq_busy, &bh->state);
2426 fsg->next_buffhd_to_fill = bh->next;
2429 /* There is a residue. For CB and CBI, simply mark the end
2430 * of the data with a short packet. However, if we are
2431 * allowed to stall, there was no data at all (residue ==
2432 * data_size), and the command failed (invalid LUN or
2433 * sense data is set), then halt the bulk-in endpoint
2434 * instead. */
2435 else if (!transport_is_bbb()) {
2436 if (mod_data.can_stall &&
2437 fsg->residue == fsg->data_size &&
2438 (!fsg->curlun || fsg->curlun->sense_data != SS_NO_SENSE)) {
2439 bh->state = BUF_STATE_EMPTY;
2440 rc = halt_bulk_in_endpoint(fsg);
2441 } else {
2442 bh->inreq->zero = 1;
2443 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2444 &bh->inreq_busy, &bh->state);
2445 fsg->next_buffhd_to_fill = bh->next;
2449 /* For Bulk-only, if we're allowed to stall then send the
2450 * short packet and halt the bulk-in endpoint. If we can't
2451 * stall, pad out the remaining data with 0's. */
2452 else {
2453 if (mod_data.can_stall) {
2454 bh->inreq->zero = 1;
2455 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2456 &bh->inreq_busy, &bh->state);
2457 fsg->next_buffhd_to_fill = bh->next;
2458 rc = halt_bulk_in_endpoint(fsg);
2459 } else
2460 rc = pad_with_zeros(fsg);
2462 break;
2464 /* We have processed all we want from the data the host has sent.
2465 * There may still be outstanding bulk-out requests. */
2466 case DATA_DIR_FROM_HOST:
2467 if (fsg->residue == 0)
2468 ; // Nothing to receive
2470 /* Did the host stop sending unexpectedly early? */
2471 else if (fsg->short_packet_received) {
2472 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2473 rc = -EINTR;
2476 /* We haven't processed all the incoming data. Even though
2477 * we may be allowed to stall, doing so would cause a race.
2478 * The controller may already have ACK'ed all the remaining
2479 * bulk-out packets, in which case the host wouldn't see a
2480 * STALL. Not realizing the endpoint was halted, it wouldn't
2481 * clear the halt -- leading to problems later on. */
2482 #if 0
2483 else if (mod_data.can_stall) {
2484 fsg_set_halt(fsg, fsg->bulk_out);
2485 raise_exception(fsg, FSG_STATE_ABORT_BULK_OUT);
2486 rc = -EINTR;
2488 #endif
2490 /* We can't stall. Read in the excess data and throw it
2491 * all away. */
2492 else
2493 rc = throw_away_data(fsg);
2494 break;
2496 return rc;
2500 static int send_status(struct fsg_dev *fsg)
2502 struct lun *curlun = fsg->curlun;
2503 struct fsg_buffhd *bh;
2504 int rc;
2505 u8 status = USB_STATUS_PASS;
2506 u32 sd, sdinfo = 0;
2508 /* Wait for the next buffer to become available */
2509 bh = fsg->next_buffhd_to_fill;
2510 while (bh->state != BUF_STATE_EMPTY) {
2511 rc = sleep_thread(fsg);
2512 if (rc)
2513 return rc;
2516 if (curlun) {
2517 sd = curlun->sense_data;
2518 sdinfo = curlun->sense_data_info;
2519 } else if (fsg->bad_lun_okay)
2520 sd = SS_NO_SENSE;
2521 else
2522 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
2524 if (fsg->phase_error) {
2525 DBG(fsg, "sending phase-error status\n");
2526 status = USB_STATUS_PHASE_ERROR;
2527 sd = SS_INVALID_COMMAND;
2528 } else if (sd != SS_NO_SENSE) {
2529 DBG(fsg, "sending command-failure status\n");
2530 status = USB_STATUS_FAIL;
2531 VDBG(fsg, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
2532 " info x%x\n",
2533 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
2536 if (transport_is_bbb()) {
2537 struct bulk_cs_wrap *csw = bh->buf;
2539 /* Store and send the Bulk-only CSW */
2540 csw->Signature = __constant_cpu_to_le32(USB_BULK_CS_SIG);
2541 csw->Tag = fsg->tag;
2542 csw->Residue = cpu_to_le32(fsg->residue);
2543 csw->Status = status;
2545 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
2546 bh->inreq->zero = 0;
2547 start_transfer(fsg, fsg->bulk_in, bh->inreq,
2548 &bh->inreq_busy, &bh->state);
2550 } else if (mod_data.transport_type == USB_PR_CB) {
2552 /* Control-Bulk transport has no status phase! */
2553 return 0;
2555 } else { // USB_PR_CBI
2556 struct interrupt_data *buf = bh->buf;
2558 /* Store and send the Interrupt data. UFI sends the ASC
2559 * and ASCQ bytes. Everything else sends a Type (which
2560 * is always 0) and the status Value. */
2561 if (mod_data.protocol_type == USB_SC_UFI) {
2562 buf->bType = ASC(sd);
2563 buf->bValue = ASCQ(sd);
2564 } else {
2565 buf->bType = 0;
2566 buf->bValue = status;
2568 fsg->intreq->length = CBI_INTERRUPT_DATA_LEN;
2570 fsg->intr_buffhd = bh; // Point to the right buffhd
2571 fsg->intreq->buf = bh->inreq->buf;
2572 fsg->intreq->context = bh;
2573 start_transfer(fsg, fsg->intr_in, fsg->intreq,
2574 &fsg->intreq_busy, &bh->state);
2577 fsg->next_buffhd_to_fill = bh->next;
2578 return 0;
2582 /*-------------------------------------------------------------------------*/
2584 /* Check whether the command is properly formed and whether its data size
2585 * and direction agree with the values we already have. */
2586 static int check_command(struct fsg_dev *fsg, int cmnd_size,
2587 enum data_direction data_dir, unsigned int mask,
2588 int needs_medium, const char *name)
2590 int i;
2591 int lun = fsg->cmnd[1] >> 5;
2592 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
2593 char hdlen[20];
2594 struct lun *curlun;
2596 /* Adjust the expected cmnd_size for protocol encapsulation padding.
2597 * Transparent SCSI doesn't pad. */
2598 if (protocol_is_scsi())
2601 /* There's some disagreement as to whether RBC pads commands or not.
2602 * We'll play it safe and accept either form. */
2603 else if (mod_data.protocol_type == USB_SC_RBC) {
2604 if (fsg->cmnd_size == 12)
2605 cmnd_size = 12;
2607 /* All the other protocols pad to 12 bytes */
2608 } else
2609 cmnd_size = 12;
2611 hdlen[0] = 0;
2612 if (fsg->data_dir != DATA_DIR_UNKNOWN)
2613 sprintf(hdlen, ", H%c=%u", dirletter[(int) fsg->data_dir],
2614 fsg->data_size);
2615 VDBG(fsg, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
2616 name, cmnd_size, dirletter[(int) data_dir],
2617 fsg->data_size_from_cmnd, fsg->cmnd_size, hdlen);
2619 /* We can't reply at all until we know the correct data direction
2620 * and size. */
2621 if (fsg->data_size_from_cmnd == 0)
2622 data_dir = DATA_DIR_NONE;
2623 if (fsg->data_dir == DATA_DIR_UNKNOWN) { // CB or CBI
2624 fsg->data_dir = data_dir;
2625 fsg->data_size = fsg->data_size_from_cmnd;
2627 } else { // Bulk-only
2628 if (fsg->data_size < fsg->data_size_from_cmnd) {
2630 /* Host data size < Device data size is a phase error.
2631 * Carry out the command, but only transfer as much
2632 * as we are allowed. */
2633 fsg->data_size_from_cmnd = fsg->data_size;
2634 fsg->phase_error = 1;
2637 fsg->residue = fsg->usb_amount_left = fsg->data_size;
2639 /* Conflicting data directions is a phase error */
2640 if (fsg->data_dir != data_dir && fsg->data_size_from_cmnd > 0) {
2641 fsg->phase_error = 1;
2642 return -EINVAL;
2645 /* Verify the length of the command itself */
2646 if (cmnd_size != fsg->cmnd_size) {
2648 /* Special case workaround: MS-Windows issues REQUEST SENSE
2649 * with cbw->Length == 12 (it should be 6). */
2650 if (fsg->cmnd[0] == SC_REQUEST_SENSE && fsg->cmnd_size == 12)
2651 cmnd_size = fsg->cmnd_size;
2652 else {
2653 fsg->phase_error = 1;
2654 return -EINVAL;
2658 /* Check that the LUN values are consistent */
2659 if (transport_is_bbb()) {
2660 if (fsg->lun != lun)
2661 DBG(fsg, "using LUN %d from CBW, "
2662 "not LUN %d from CDB\n",
2663 fsg->lun, lun);
2664 } else
2665 fsg->lun = lun; // Use LUN from the command
2667 /* Check the LUN */
2668 if (fsg->lun >= 0 && fsg->lun < fsg->nluns) {
2669 fsg->curlun = curlun = &fsg->luns[fsg->lun];
2670 if (fsg->cmnd[0] != SC_REQUEST_SENSE) {
2671 curlun->sense_data = SS_NO_SENSE;
2672 curlun->sense_data_info = 0;
2673 curlun->info_valid = 0;
2675 } else {
2676 fsg->curlun = curlun = NULL;
2677 fsg->bad_lun_okay = 0;
2679 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
2680 * to use unsupported LUNs; all others may not. */
2681 if (fsg->cmnd[0] != SC_INQUIRY &&
2682 fsg->cmnd[0] != SC_REQUEST_SENSE) {
2683 DBG(fsg, "unsupported LUN %d\n", fsg->lun);
2684 return -EINVAL;
2688 /* If a unit attention condition exists, only INQUIRY and
2689 * REQUEST SENSE commands are allowed; anything else must fail. */
2690 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
2691 fsg->cmnd[0] != SC_INQUIRY &&
2692 fsg->cmnd[0] != SC_REQUEST_SENSE) {
2693 curlun->sense_data = curlun->unit_attention_data;
2694 curlun->unit_attention_data = SS_NO_SENSE;
2695 return -EINVAL;
2698 /* Check that only command bytes listed in the mask are non-zero */
2699 fsg->cmnd[1] &= 0x1f; // Mask away the LUN
2700 for (i = 1; i < cmnd_size; ++i) {
2701 if (fsg->cmnd[i] && !(mask & (1 << i))) {
2702 if (curlun)
2703 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
2704 return -EINVAL;
2708 /* If the medium isn't mounted and the command needs to access
2709 * it, return an error. */
2710 if (curlun && !backing_file_is_open(curlun) && needs_medium) {
2711 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
2712 return -EINVAL;
2715 return 0;
2719 static int do_scsi_command(struct fsg_dev *fsg)
2721 struct fsg_buffhd *bh;
2722 int rc;
2723 int reply = -EINVAL;
2724 int i;
2725 static char unknown[16];
2727 dump_cdb(fsg);
2729 /* Wait for the next buffer to become available for data or status */
2730 bh = fsg->next_buffhd_to_drain = fsg->next_buffhd_to_fill;
2731 while (bh->state != BUF_STATE_EMPTY) {
2732 rc = sleep_thread(fsg);
2733 if (rc)
2734 return rc;
2736 fsg->phase_error = 0;
2737 fsg->short_packet_received = 0;
2739 down_read(&fsg->filesem); // We're using the backing file
2740 switch (fsg->cmnd[0]) {
2742 case SC_INQUIRY:
2743 fsg->data_size_from_cmnd = fsg->cmnd[4];
2744 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2745 (1<<4), 0,
2746 "INQUIRY")) == 0)
2747 reply = do_inquiry(fsg, bh);
2748 break;
2750 case SC_MODE_SELECT_6:
2751 fsg->data_size_from_cmnd = fsg->cmnd[4];
2752 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2753 (1<<1) | (1<<4), 0,
2754 "MODE SELECT(6)")) == 0)
2755 reply = do_mode_select(fsg, bh);
2756 break;
2758 case SC_MODE_SELECT_10:
2759 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2760 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2761 (1<<1) | (3<<7), 0,
2762 "MODE SELECT(10)")) == 0)
2763 reply = do_mode_select(fsg, bh);
2764 break;
2766 case SC_MODE_SENSE_6:
2767 fsg->data_size_from_cmnd = fsg->cmnd[4];
2768 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2769 (1<<1) | (1<<2) | (1<<4), 0,
2770 "MODE SENSE(6)")) == 0)
2771 reply = do_mode_sense(fsg, bh);
2772 break;
2774 case SC_MODE_SENSE_10:
2775 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2776 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2777 (1<<1) | (1<<2) | (3<<7), 0,
2778 "MODE SENSE(10)")) == 0)
2779 reply = do_mode_sense(fsg, bh);
2780 break;
2782 case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
2783 fsg->data_size_from_cmnd = 0;
2784 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2785 (1<<4), 0,
2786 "PREVENT-ALLOW MEDIUM REMOVAL")) == 0)
2787 reply = do_prevent_allow(fsg);
2788 break;
2790 case SC_READ_6:
2791 i = fsg->cmnd[4];
2792 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2793 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2794 (7<<1) | (1<<4), 1,
2795 "READ(6)")) == 0)
2796 reply = do_read(fsg);
2797 break;
2799 case SC_READ_10:
2800 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
2801 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2802 (1<<1) | (0xf<<2) | (3<<7), 1,
2803 "READ(10)")) == 0)
2804 reply = do_read(fsg);
2805 break;
2807 case SC_READ_12:
2808 fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
2809 if ((reply = check_command(fsg, 12, DATA_DIR_TO_HOST,
2810 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2811 "READ(12)")) == 0)
2812 reply = do_read(fsg);
2813 break;
2815 case SC_READ_CAPACITY:
2816 fsg->data_size_from_cmnd = 8;
2817 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2818 (0xf<<2) | (1<<8), 1,
2819 "READ CAPACITY")) == 0)
2820 reply = do_read_capacity(fsg, bh);
2821 break;
2823 case SC_READ_FORMAT_CAPACITIES:
2824 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]);
2825 if ((reply = check_command(fsg, 10, DATA_DIR_TO_HOST,
2826 (3<<7), 1,
2827 "READ FORMAT CAPACITIES")) == 0)
2828 reply = do_read_format_capacities(fsg, bh);
2829 break;
2831 case SC_REQUEST_SENSE:
2832 fsg->data_size_from_cmnd = fsg->cmnd[4];
2833 if ((reply = check_command(fsg, 6, DATA_DIR_TO_HOST,
2834 (1<<4), 0,
2835 "REQUEST SENSE")) == 0)
2836 reply = do_request_sense(fsg, bh);
2837 break;
2839 case SC_START_STOP_UNIT:
2840 fsg->data_size_from_cmnd = 0;
2841 if ((reply = check_command(fsg, 6, DATA_DIR_NONE,
2842 (1<<1) | (1<<4), 0,
2843 "START-STOP UNIT")) == 0)
2844 reply = do_start_stop(fsg);
2845 break;
2847 case SC_SYNCHRONIZE_CACHE:
2848 fsg->data_size_from_cmnd = 0;
2849 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2850 (0xf<<2) | (3<<7), 1,
2851 "SYNCHRONIZE CACHE")) == 0)
2852 reply = do_synchronize_cache(fsg);
2853 break;
2855 case SC_TEST_UNIT_READY:
2856 fsg->data_size_from_cmnd = 0;
2857 reply = check_command(fsg, 6, DATA_DIR_NONE,
2858 0, 1,
2859 "TEST UNIT READY");
2860 break;
2862 /* Although optional, this command is used by MS-Windows. We
2863 * support a minimal version: BytChk must be 0. */
2864 case SC_VERIFY:
2865 fsg->data_size_from_cmnd = 0;
2866 if ((reply = check_command(fsg, 10, DATA_DIR_NONE,
2867 (1<<1) | (0xf<<2) | (3<<7), 1,
2868 "VERIFY")) == 0)
2869 reply = do_verify(fsg);
2870 break;
2872 case SC_WRITE_6:
2873 i = fsg->cmnd[4];
2874 fsg->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2875 if ((reply = check_command(fsg, 6, DATA_DIR_FROM_HOST,
2876 (7<<1) | (1<<4), 1,
2877 "WRITE(6)")) == 0)
2878 reply = do_write(fsg);
2879 break;
2881 case SC_WRITE_10:
2882 fsg->data_size_from_cmnd = get_be16(&fsg->cmnd[7]) << 9;
2883 if ((reply = check_command(fsg, 10, DATA_DIR_FROM_HOST,
2884 (1<<1) | (0xf<<2) | (3<<7), 1,
2885 "WRITE(10)")) == 0)
2886 reply = do_write(fsg);
2887 break;
2889 case SC_WRITE_12:
2890 fsg->data_size_from_cmnd = get_be32(&fsg->cmnd[6]) << 9;
2891 if ((reply = check_command(fsg, 12, DATA_DIR_FROM_HOST,
2892 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2893 "WRITE(12)")) == 0)
2894 reply = do_write(fsg);
2895 break;
2897 /* Some mandatory commands that we recognize but don't implement.
2898 * They don't mean much in this setting. It's left as an exercise
2899 * for anyone interested to implement RESERVE and RELEASE in terms
2900 * of Posix locks. */
2901 case SC_FORMAT_UNIT:
2902 case SC_RELEASE:
2903 case SC_RESERVE:
2904 case SC_SEND_DIAGNOSTIC:
2905 // Fall through
2907 default:
2908 fsg->data_size_from_cmnd = 0;
2909 sprintf(unknown, "Unknown x%02x", fsg->cmnd[0]);
2910 if ((reply = check_command(fsg, fsg->cmnd_size,
2911 DATA_DIR_UNKNOWN, 0xff, 0, unknown)) == 0) {
2912 fsg->curlun->sense_data = SS_INVALID_COMMAND;
2913 reply = -EINVAL;
2915 break;
2917 up_read(&fsg->filesem);
2919 if (reply == -EINTR || signal_pending(current))
2920 return -EINTR;
2922 /* Set up the single reply buffer for finish_reply() */
2923 if (reply == -EINVAL)
2924 reply = 0; // Error reply length
2925 if (reply >= 0 && fsg->data_dir == DATA_DIR_TO_HOST) {
2926 reply = min((u32) reply, fsg->data_size_from_cmnd);
2927 bh->inreq->length = reply;
2928 bh->state = BUF_STATE_FULL;
2929 fsg->residue -= reply;
2930 } // Otherwise it's already set
2932 return 0;
2936 /*-------------------------------------------------------------------------*/
2938 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2940 struct usb_request *req = bh->outreq;
2941 struct bulk_cb_wrap *cbw = req->buf;
2943 /* Was this a real packet? */
2944 if (req->status)
2945 return -EINVAL;
2947 /* Is the CBW valid? */
2948 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2949 cbw->Signature != __constant_cpu_to_le32(
2950 USB_BULK_CB_SIG)) {
2951 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2952 req->actual,
2953 le32_to_cpu(cbw->Signature));
2955 /* The Bulk-only spec says we MUST stall the bulk pipes!
2956 * If we want to avoid stalls, set a flag so that we will
2957 * clear the endpoint halts at the next reset. */
2958 if (!mod_data.can_stall)
2959 set_bit(CLEAR_BULK_HALTS, &fsg->atomic_bitflags);
2960 fsg_set_halt(fsg, fsg->bulk_out);
2961 halt_bulk_in_endpoint(fsg);
2962 return -EINVAL;
2965 /* Is the CBW meaningful? */
2966 if (cbw->Lun >= MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2967 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2968 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2969 "cmdlen %u\n",
2970 cbw->Lun, cbw->Flags, cbw->Length);
2972 /* We can do anything we want here, so let's stall the
2973 * bulk pipes if we are allowed to. */
2974 if (mod_data.can_stall) {
2975 fsg_set_halt(fsg, fsg->bulk_out);
2976 halt_bulk_in_endpoint(fsg);
2978 return -EINVAL;
2981 /* Save the command for later */
2982 fsg->cmnd_size = cbw->Length;
2983 memcpy(fsg->cmnd, cbw->CDB, fsg->cmnd_size);
2984 if (cbw->Flags & USB_BULK_IN_FLAG)
2985 fsg->data_dir = DATA_DIR_TO_HOST;
2986 else
2987 fsg->data_dir = DATA_DIR_FROM_HOST;
2988 fsg->data_size = le32_to_cpu(cbw->DataTransferLength);
2989 if (fsg->data_size == 0)
2990 fsg->data_dir = DATA_DIR_NONE;
2991 fsg->lun = cbw->Lun;
2992 fsg->tag = cbw->Tag;
2993 return 0;
2997 static int get_next_command(struct fsg_dev *fsg)
2999 struct fsg_buffhd *bh;
3000 int rc = 0;
3002 if (transport_is_bbb()) {
3004 /* Wait for the next buffer to become available */
3005 bh = fsg->next_buffhd_to_fill;
3006 while (bh->state != BUF_STATE_EMPTY) {
3007 rc = sleep_thread(fsg);
3008 if (rc)
3009 return rc;
3012 /* Queue a request to read a Bulk-only CBW */
3013 set_bulk_out_req_length(fsg, bh, USB_BULK_CB_WRAP_LEN);
3014 bh->outreq->short_not_ok = 1;
3015 start_transfer(fsg, fsg->bulk_out, bh->outreq,
3016 &bh->outreq_busy, &bh->state);
3018 /* We will drain the buffer in software, which means we
3019 * can reuse it for the next filling. No need to advance
3020 * next_buffhd_to_fill. */
3022 /* Wait for the CBW to arrive */
3023 while (bh->state != BUF_STATE_FULL) {
3024 rc = sleep_thread(fsg);
3025 if (rc)
3026 return rc;
3028 smp_rmb();
3029 rc = received_cbw(fsg, bh);
3030 bh->state = BUF_STATE_EMPTY;
3032 } else { // USB_PR_CB or USB_PR_CBI
3034 /* Wait for the next command to arrive */
3035 while (fsg->cbbuf_cmnd_size == 0) {
3036 rc = sleep_thread(fsg);
3037 if (rc)
3038 return rc;
3041 /* Is the previous status interrupt request still busy?
3042 * The host is allowed to skip reading the status,
3043 * so we must cancel it. */
3044 if (fsg->intreq_busy)
3045 usb_ep_dequeue(fsg->intr_in, fsg->intreq);
3047 /* Copy the command and mark the buffer empty */
3048 fsg->data_dir = DATA_DIR_UNKNOWN;
3049 spin_lock_irq(&fsg->lock);
3050 fsg->cmnd_size = fsg->cbbuf_cmnd_size;
3051 memcpy(fsg->cmnd, fsg->cbbuf_cmnd, fsg->cmnd_size);
3052 fsg->cbbuf_cmnd_size = 0;
3053 spin_unlock_irq(&fsg->lock);
3055 return rc;
3059 /*-------------------------------------------------------------------------*/
3061 static int enable_endpoint(struct fsg_dev *fsg, struct usb_ep *ep,
3062 const struct usb_endpoint_descriptor *d)
3064 int rc;
3066 ep->driver_data = fsg;
3067 rc = usb_ep_enable(ep, d);
3068 if (rc)
3069 ERROR(fsg, "can't enable %s, result %d\n", ep->name, rc);
3070 return rc;
3073 static int alloc_request(struct fsg_dev *fsg, struct usb_ep *ep,
3074 struct usb_request **preq)
3076 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
3077 if (*preq)
3078 return 0;
3079 ERROR(fsg, "can't allocate request for %s\n", ep->name);
3080 return -ENOMEM;
3084 * Reset interface setting and re-init endpoint state (toggle etc).
3085 * Call with altsetting < 0 to disable the interface. The only other
3086 * available altsetting is 0, which enables the interface.
3088 static int do_set_interface(struct fsg_dev *fsg, int altsetting)
3090 int rc = 0;
3091 int i;
3092 const struct usb_endpoint_descriptor *d;
3094 if (fsg->running)
3095 DBG(fsg, "reset interface\n");
3097 reset:
3098 /* Deallocate the requests */
3099 for (i = 0; i < NUM_BUFFERS; ++i) {
3100 struct fsg_buffhd *bh = &fsg->buffhds[i];
3102 if (bh->inreq) {
3103 usb_ep_free_request(fsg->bulk_in, bh->inreq);
3104 bh->inreq = NULL;
3106 if (bh->outreq) {
3107 usb_ep_free_request(fsg->bulk_out, bh->outreq);
3108 bh->outreq = NULL;
3111 if (fsg->intreq) {
3112 usb_ep_free_request(fsg->intr_in, fsg->intreq);
3113 fsg->intreq = NULL;
3116 /* Disable the endpoints */
3117 if (fsg->bulk_in_enabled) {
3118 usb_ep_disable(fsg->bulk_in);
3119 fsg->bulk_in_enabled = 0;
3121 if (fsg->bulk_out_enabled) {
3122 usb_ep_disable(fsg->bulk_out);
3123 fsg->bulk_out_enabled = 0;
3125 if (fsg->intr_in_enabled) {
3126 usb_ep_disable(fsg->intr_in);
3127 fsg->intr_in_enabled = 0;
3130 fsg->running = 0;
3131 if (altsetting < 0 || rc != 0)
3132 return rc;
3134 DBG(fsg, "set interface %d\n", altsetting);
3136 /* Enable the endpoints */
3137 d = ep_desc(fsg->gadget, &fs_bulk_in_desc, &hs_bulk_in_desc);
3138 if ((rc = enable_endpoint(fsg, fsg->bulk_in, d)) != 0)
3139 goto reset;
3140 fsg->bulk_in_enabled = 1;
3142 d = ep_desc(fsg->gadget, &fs_bulk_out_desc, &hs_bulk_out_desc);
3143 if ((rc = enable_endpoint(fsg, fsg->bulk_out, d)) != 0)
3144 goto reset;
3145 fsg->bulk_out_enabled = 1;
3146 fsg->bulk_out_maxpacket = le16_to_cpu(d->wMaxPacketSize);
3148 if (transport_is_cbi()) {
3149 d = ep_desc(fsg->gadget, &fs_intr_in_desc, &hs_intr_in_desc);
3150 if ((rc = enable_endpoint(fsg, fsg->intr_in, d)) != 0)
3151 goto reset;
3152 fsg->intr_in_enabled = 1;
3155 /* Allocate the requests */
3156 for (i = 0; i < NUM_BUFFERS; ++i) {
3157 struct fsg_buffhd *bh = &fsg->buffhds[i];
3159 if ((rc = alloc_request(fsg, fsg->bulk_in, &bh->inreq)) != 0)
3160 goto reset;
3161 if ((rc = alloc_request(fsg, fsg->bulk_out, &bh->outreq)) != 0)
3162 goto reset;
3163 bh->inreq->buf = bh->outreq->buf = bh->buf;
3164 bh->inreq->context = bh->outreq->context = bh;
3165 bh->inreq->complete = bulk_in_complete;
3166 bh->outreq->complete = bulk_out_complete;
3168 if (transport_is_cbi()) {
3169 if ((rc = alloc_request(fsg, fsg->intr_in, &fsg->intreq)) != 0)
3170 goto reset;
3171 fsg->intreq->complete = intr_in_complete;
3174 fsg->running = 1;
3175 for (i = 0; i < fsg->nluns; ++i)
3176 fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3177 return rc;
3182 * Change our operational configuration. This code must agree with the code
3183 * that returns config descriptors, and with interface altsetting code.
3185 * It's also responsible for power management interactions. Some
3186 * configurations might not work with our current power sources.
3187 * For now we just assume the gadget is always self-powered.
3189 static int do_set_config(struct fsg_dev *fsg, u8 new_config)
3191 int rc = 0;
3193 /* Disable the single interface */
3194 if (fsg->config != 0) {
3195 DBG(fsg, "reset config\n");
3196 fsg->config = 0;
3197 rc = do_set_interface(fsg, -1);
3200 /* Enable the interface */
3201 if (new_config != 0) {
3202 fsg->config = new_config;
3203 if ((rc = do_set_interface(fsg, 0)) != 0)
3204 fsg->config = 0; // Reset on errors
3205 else {
3206 char *speed;
3208 switch (fsg->gadget->speed) {
3209 case USB_SPEED_LOW: speed = "low"; break;
3210 case USB_SPEED_FULL: speed = "full"; break;
3211 case USB_SPEED_HIGH: speed = "high"; break;
3212 default: speed = "?"; break;
3214 INFO(fsg, "%s speed config #%d\n", speed, fsg->config);
3217 return rc;
3221 /*-------------------------------------------------------------------------*/
3223 static void handle_exception(struct fsg_dev *fsg)
3225 siginfo_t info;
3226 int sig;
3227 int i;
3228 int num_active;
3229 struct fsg_buffhd *bh;
3230 enum fsg_state old_state;
3231 u8 new_config;
3232 struct lun *curlun;
3233 unsigned int exception_req_tag;
3234 int rc;
3236 /* Clear the existing signals. Anything but SIGUSR1 is converted
3237 * into a high-priority EXIT exception. */
3238 for (;;) {
3239 sig = dequeue_signal_lock(current, &current->blocked, &info);
3240 if (!sig)
3241 break;
3242 if (sig != SIGUSR1) {
3243 if (fsg->state < FSG_STATE_EXIT)
3244 DBG(fsg, "Main thread exiting on signal\n");
3245 raise_exception(fsg, FSG_STATE_EXIT);
3249 /* Cancel all the pending transfers */
3250 if (fsg->intreq_busy)
3251 usb_ep_dequeue(fsg->intr_in, fsg->intreq);
3252 for (i = 0; i < NUM_BUFFERS; ++i) {
3253 bh = &fsg->buffhds[i];
3254 if (bh->inreq_busy)
3255 usb_ep_dequeue(fsg->bulk_in, bh->inreq);
3256 if (bh->outreq_busy)
3257 usb_ep_dequeue(fsg->bulk_out, bh->outreq);
3260 /* Wait until everything is idle */
3261 for (;;) {
3262 num_active = fsg->intreq_busy;
3263 for (i = 0; i < NUM_BUFFERS; ++i) {
3264 bh = &fsg->buffhds[i];
3265 num_active += bh->inreq_busy + bh->outreq_busy;
3267 if (num_active == 0)
3268 break;
3269 if (sleep_thread(fsg))
3270 return;
3273 /* Clear out the controller's fifos */
3274 if (fsg->bulk_in_enabled)
3275 usb_ep_fifo_flush(fsg->bulk_in);
3276 if (fsg->bulk_out_enabled)
3277 usb_ep_fifo_flush(fsg->bulk_out);
3278 if (fsg->intr_in_enabled)
3279 usb_ep_fifo_flush(fsg->intr_in);
3281 /* Reset the I/O buffer states and pointers, the SCSI
3282 * state, and the exception. Then invoke the handler. */
3283 spin_lock_irq(&fsg->lock);
3285 for (i = 0; i < NUM_BUFFERS; ++i) {
3286 bh = &fsg->buffhds[i];
3287 bh->state = BUF_STATE_EMPTY;
3289 fsg->next_buffhd_to_fill = fsg->next_buffhd_to_drain =
3290 &fsg->buffhds[0];
3292 exception_req_tag = fsg->exception_req_tag;
3293 new_config = fsg->new_config;
3294 old_state = fsg->state;
3296 if (old_state == FSG_STATE_ABORT_BULK_OUT)
3297 fsg->state = FSG_STATE_STATUS_PHASE;
3298 else {
3299 for (i = 0; i < fsg->nluns; ++i) {
3300 curlun = &fsg->luns[i];
3301 curlun->prevent_medium_removal = 0;
3302 curlun->sense_data = curlun->unit_attention_data =
3303 SS_NO_SENSE;
3304 curlun->sense_data_info = 0;
3305 curlun->info_valid = 0;
3307 fsg->state = FSG_STATE_IDLE;
3309 spin_unlock_irq(&fsg->lock);
3311 /* Carry out any extra actions required for the exception */
3312 switch (old_state) {
3313 default:
3314 break;
3316 case FSG_STATE_ABORT_BULK_OUT:
3317 send_status(fsg);
3318 spin_lock_irq(&fsg->lock);
3319 if (fsg->state == FSG_STATE_STATUS_PHASE)
3320 fsg->state = FSG_STATE_IDLE;
3321 spin_unlock_irq(&fsg->lock);
3322 break;
3324 case FSG_STATE_RESET:
3325 /* In case we were forced against our will to halt a
3326 * bulk endpoint, clear the halt now. (The SuperH UDC
3327 * requires this.) */
3328 if (test_and_clear_bit(CLEAR_BULK_HALTS,
3329 &fsg->atomic_bitflags)) {
3330 usb_ep_clear_halt(fsg->bulk_in);
3331 usb_ep_clear_halt(fsg->bulk_out);
3334 if (transport_is_bbb()) {
3335 if (fsg->ep0_req_tag == exception_req_tag)
3336 ep0_queue(fsg); // Complete the status stage
3338 } else if (transport_is_cbi())
3339 send_status(fsg); // Status by interrupt pipe
3341 /* Technically this should go here, but it would only be
3342 * a waste of time. Ditto for the INTERFACE_CHANGE and
3343 * CONFIG_CHANGE cases. */
3344 // for (i = 0; i < fsg->nluns; ++i)
3345 // fsg->luns[i].unit_attention_data = SS_RESET_OCCURRED;
3346 break;
3348 case FSG_STATE_INTERFACE_CHANGE:
3349 rc = do_set_interface(fsg, 0);
3350 if (fsg->ep0_req_tag != exception_req_tag)
3351 break;
3352 if (rc != 0) // STALL on errors
3353 fsg_set_halt(fsg, fsg->ep0);
3354 else // Complete the status stage
3355 ep0_queue(fsg);
3356 break;
3358 case FSG_STATE_CONFIG_CHANGE:
3359 rc = do_set_config(fsg, new_config);
3360 if (fsg->ep0_req_tag != exception_req_tag)
3361 break;
3362 if (rc != 0) // STALL on errors
3363 fsg_set_halt(fsg, fsg->ep0);
3364 else // Complete the status stage
3365 ep0_queue(fsg);
3366 break;
3368 case FSG_STATE_DISCONNECT:
3369 fsync_all(fsg);
3370 do_set_config(fsg, 0); // Unconfigured state
3371 break;
3373 case FSG_STATE_EXIT:
3374 case FSG_STATE_TERMINATED:
3375 do_set_config(fsg, 0); // Free resources
3376 spin_lock_irq(&fsg->lock);
3377 fsg->state = FSG_STATE_TERMINATED; // Stop the thread
3378 spin_unlock_irq(&fsg->lock);
3379 break;
3384 /*-------------------------------------------------------------------------*/
3386 static int fsg_main_thread(void *fsg_)
3388 struct fsg_dev *fsg = fsg_;
3390 /* Allow the thread to be killed by a signal, but set the signal mask
3391 * to block everything but INT, TERM, KILL, and USR1. */
3392 allow_signal(SIGINT);
3393 allow_signal(SIGTERM);
3394 allow_signal(SIGKILL);
3395 allow_signal(SIGUSR1);
3397 /* Allow the thread to be frozen */
3398 set_freezable();
3400 /* Arrange for userspace references to be interpreted as kernel
3401 * pointers. That way we can pass a kernel pointer to a routine
3402 * that expects a __user pointer and it will work okay. */
3403 set_fs(get_ds());
3405 /* The main loop */
3406 while (fsg->state != FSG_STATE_TERMINATED) {
3407 if (exception_in_progress(fsg) || signal_pending(current)) {
3408 handle_exception(fsg);
3409 continue;
3412 if (!fsg->running) {
3413 sleep_thread(fsg);
3414 continue;
3417 if (get_next_command(fsg))
3418 continue;
3420 spin_lock_irq(&fsg->lock);
3421 if (!exception_in_progress(fsg))
3422 fsg->state = FSG_STATE_DATA_PHASE;
3423 spin_unlock_irq(&fsg->lock);
3425 if (do_scsi_command(fsg) || finish_reply(fsg))
3426 continue;
3428 spin_lock_irq(&fsg->lock);
3429 if (!exception_in_progress(fsg))
3430 fsg->state = FSG_STATE_STATUS_PHASE;
3431 spin_unlock_irq(&fsg->lock);
3433 if (send_status(fsg))
3434 continue;
3436 spin_lock_irq(&fsg->lock);
3437 if (!exception_in_progress(fsg))
3438 fsg->state = FSG_STATE_IDLE;
3439 spin_unlock_irq(&fsg->lock);
3442 spin_lock_irq(&fsg->lock);
3443 fsg->thread_task = NULL;
3444 spin_unlock_irq(&fsg->lock);
3446 /* In case we are exiting because of a signal, unregister the
3447 * gadget driver and close the backing file. */
3448 if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags)) {
3449 usb_gadget_unregister_driver(&fsg_driver);
3450 close_all_backing_files(fsg);
3453 /* Let the unbind and cleanup routines know the thread has exited */
3454 complete_and_exit(&fsg->thread_notifier, 0);
3458 /*-------------------------------------------------------------------------*/
3460 /* If the next two routines are called while the gadget is registered,
3461 * the caller must own fsg->filesem for writing. */
3463 static int open_backing_file(struct lun *curlun, const char *filename)
3465 int ro;
3466 struct file *filp = NULL;
3467 int rc = -EINVAL;
3468 struct inode *inode = NULL;
3469 loff_t size;
3470 loff_t num_sectors;
3472 /* R/W if we can, R/O if we must */
3473 ro = curlun->ro;
3474 if (!ro) {
3475 filp = filp_open(filename, O_RDWR | O_LARGEFILE, 0);
3476 if (-EROFS == PTR_ERR(filp))
3477 ro = 1;
3479 if (ro)
3480 filp = filp_open(filename, O_RDONLY | O_LARGEFILE, 0);
3481 if (IS_ERR(filp)) {
3482 LINFO(curlun, "unable to open backing file: %s\n", filename);
3483 return PTR_ERR(filp);
3486 if (!(filp->f_mode & FMODE_WRITE))
3487 ro = 1;
3489 if (filp->f_path.dentry)
3490 inode = filp->f_path.dentry->d_inode;
3491 if (inode && S_ISBLK(inode->i_mode)) {
3492 if (bdev_read_only(inode->i_bdev))
3493 ro = 1;
3494 } else if (!inode || !S_ISREG(inode->i_mode)) {
3495 LINFO(curlun, "invalid file type: %s\n", filename);
3496 goto out;
3499 /* If we can't read the file, it's no good.
3500 * If we can't write the file, use it read-only. */
3501 if (!filp->f_op || !(filp->f_op->read || filp->f_op->aio_read)) {
3502 LINFO(curlun, "file not readable: %s\n", filename);
3503 goto out;
3505 if (!(filp->f_op->write || filp->f_op->aio_write))
3506 ro = 1;
3508 size = i_size_read(inode->i_mapping->host);
3509 if (size < 0) {
3510 LINFO(curlun, "unable to find file size: %s\n", filename);
3511 rc = (int) size;
3512 goto out;
3514 num_sectors = size >> 9; // File size in 512-byte sectors
3515 if (num_sectors == 0) {
3516 LINFO(curlun, "file too small: %s\n", filename);
3517 rc = -ETOOSMALL;
3518 goto out;
3521 get_file(filp);
3522 curlun->ro = ro;
3523 curlun->filp = filp;
3524 curlun->file_length = size;
3525 curlun->num_sectors = num_sectors;
3526 LDBG(curlun, "open backing file: %s\n", filename);
3527 rc = 0;
3529 out:
3530 filp_close(filp, current->files);
3531 return rc;
3535 static void close_backing_file(struct lun *curlun)
3537 if (curlun->filp) {
3538 LDBG(curlun, "close backing file\n");
3539 fput(curlun->filp);
3540 curlun->filp = NULL;
3544 static void close_all_backing_files(struct fsg_dev *fsg)
3546 int i;
3548 for (i = 0; i < fsg->nluns; ++i)
3549 close_backing_file(&fsg->luns[i]);
3553 static ssize_t show_ro(struct device *dev, struct device_attribute *attr, char *buf)
3555 struct lun *curlun = dev_to_lun(dev);
3557 return sprintf(buf, "%d\n", curlun->ro);
3560 static ssize_t show_file(struct device *dev, struct device_attribute *attr,
3561 char *buf)
3563 struct lun *curlun = dev_to_lun(dev);
3564 struct fsg_dev *fsg = dev_get_drvdata(dev);
3565 char *p;
3566 ssize_t rc;
3568 down_read(&fsg->filesem);
3569 if (backing_file_is_open(curlun)) { // Get the complete pathname
3570 p = d_path(curlun->filp->f_path.dentry,
3571 curlun->filp->f_path.mnt, buf, PAGE_SIZE - 1);
3572 if (IS_ERR(p))
3573 rc = PTR_ERR(p);
3574 else {
3575 rc = strlen(p);
3576 memmove(buf, p, rc);
3577 buf[rc] = '\n'; // Add a newline
3578 buf[++rc] = 0;
3580 } else { // No file, return 0 bytes
3581 *buf = 0;
3582 rc = 0;
3584 up_read(&fsg->filesem);
3585 return rc;
3589 static ssize_t store_ro(struct device *dev, struct device_attribute *attr,
3590 const char *buf, size_t count)
3592 ssize_t rc = count;
3593 struct lun *curlun = dev_to_lun(dev);
3594 struct fsg_dev *fsg = dev_get_drvdata(dev);
3595 int i;
3597 if (sscanf(buf, "%d", &i) != 1)
3598 return -EINVAL;
3600 /* Allow the write-enable status to change only while the backing file
3601 * is closed. */
3602 down_read(&fsg->filesem);
3603 if (backing_file_is_open(curlun)) {
3604 LDBG(curlun, "read-only status change prevented\n");
3605 rc = -EBUSY;
3606 } else {
3607 curlun->ro = !!i;
3608 LDBG(curlun, "read-only status set to %d\n", curlun->ro);
3610 up_read(&fsg->filesem);
3611 return rc;
3614 static ssize_t store_file(struct device *dev, struct device_attribute *attr,
3615 const char *buf, size_t count)
3617 struct lun *curlun = dev_to_lun(dev);
3618 struct fsg_dev *fsg = dev_get_drvdata(dev);
3619 int rc = 0;
3621 if (curlun->prevent_medium_removal && backing_file_is_open(curlun)) {
3622 LDBG(curlun, "eject attempt prevented\n");
3623 return -EBUSY; // "Door is locked"
3626 /* Remove a trailing newline */
3627 if (count > 0 && buf[count-1] == '\n')
3628 ((char *) buf)[count-1] = 0; // Ugh!
3630 /* Eject current medium */
3631 down_write(&fsg->filesem);
3632 if (backing_file_is_open(curlun)) {
3633 close_backing_file(curlun);
3634 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
3637 /* Load new medium */
3638 if (count > 0 && buf[0]) {
3639 rc = open_backing_file(curlun, buf);
3640 if (rc == 0)
3641 curlun->unit_attention_data =
3642 SS_NOT_READY_TO_READY_TRANSITION;
3644 up_write(&fsg->filesem);
3645 return (rc < 0 ? rc : count);
3649 /* The write permissions and store_xxx pointers are set in fsg_bind() */
3650 static DEVICE_ATTR(ro, 0444, show_ro, NULL);
3651 static DEVICE_ATTR(file, 0444, show_file, NULL);
3654 /*-------------------------------------------------------------------------*/
3656 static void fsg_release(struct kref *ref)
3658 struct fsg_dev *fsg = container_of(ref, struct fsg_dev, ref);
3660 kfree(fsg->luns);
3661 kfree(fsg);
3664 static void lun_release(struct device *dev)
3666 struct fsg_dev *fsg = dev_get_drvdata(dev);
3668 kref_put(&fsg->ref, fsg_release);
3671 static void /* __init_or_exit */ fsg_unbind(struct usb_gadget *gadget)
3673 struct fsg_dev *fsg = get_gadget_data(gadget);
3674 int i;
3675 struct lun *curlun;
3676 struct usb_request *req = fsg->ep0req;
3678 DBG(fsg, "unbind\n");
3679 clear_bit(REGISTERED, &fsg->atomic_bitflags);
3681 /* Unregister the sysfs attribute files and the LUNs */
3682 for (i = 0; i < fsg->nluns; ++i) {
3683 curlun = &fsg->luns[i];
3684 if (curlun->registered) {
3685 device_remove_file(&curlun->dev, &dev_attr_ro);
3686 device_remove_file(&curlun->dev, &dev_attr_file);
3687 device_unregister(&curlun->dev);
3688 curlun->registered = 0;
3692 /* If the thread isn't already dead, tell it to exit now */
3693 if (fsg->state != FSG_STATE_TERMINATED) {
3694 raise_exception(fsg, FSG_STATE_EXIT);
3695 wait_for_completion(&fsg->thread_notifier);
3697 /* The cleanup routine waits for this completion also */
3698 complete(&fsg->thread_notifier);
3701 /* Free the data buffers */
3702 for (i = 0; i < NUM_BUFFERS; ++i)
3703 kfree(fsg->buffhds[i].buf);
3705 /* Free the request and buffer for endpoint 0 */
3706 if (req) {
3707 kfree(req->buf);
3708 usb_ep_free_request(fsg->ep0, req);
3711 set_gadget_data(gadget, NULL);
3715 static int __init check_parameters(struct fsg_dev *fsg)
3717 int prot;
3718 int gcnum;
3720 /* Store the default values */
3721 mod_data.transport_type = USB_PR_BULK;
3722 mod_data.transport_name = "Bulk-only";
3723 mod_data.protocol_type = USB_SC_SCSI;
3724 mod_data.protocol_name = "Transparent SCSI";
3726 if (gadget_is_sh(fsg->gadget))
3727 mod_data.can_stall = 0;
3729 if (mod_data.release == 0xffff) { // Parameter wasn't set
3730 /* The sa1100 controller is not supported */
3731 if (gadget_is_sa1100(fsg->gadget))
3732 gcnum = -1;
3733 else
3734 gcnum = usb_gadget_controller_number(fsg->gadget);
3735 if (gcnum >= 0)
3736 mod_data.release = 0x0300 + gcnum;
3737 else {
3738 WARN(fsg, "controller '%s' not recognized\n",
3739 fsg->gadget->name);
3740 mod_data.release = 0x0399;
3744 prot = simple_strtol(mod_data.protocol_parm, NULL, 0);
3746 #ifdef CONFIG_USB_FILE_STORAGE_TEST
3747 if (strnicmp(mod_data.transport_parm, "BBB", 10) == 0) {
3748 ; // Use default setting
3749 } else if (strnicmp(mod_data.transport_parm, "CB", 10) == 0) {
3750 mod_data.transport_type = USB_PR_CB;
3751 mod_data.transport_name = "Control-Bulk";
3752 } else if (strnicmp(mod_data.transport_parm, "CBI", 10) == 0) {
3753 mod_data.transport_type = USB_PR_CBI;
3754 mod_data.transport_name = "Control-Bulk-Interrupt";
3755 } else {
3756 ERROR(fsg, "invalid transport: %s\n", mod_data.transport_parm);
3757 return -EINVAL;
3760 if (strnicmp(mod_data.protocol_parm, "SCSI", 10) == 0 ||
3761 prot == USB_SC_SCSI) {
3762 ; // Use default setting
3763 } else if (strnicmp(mod_data.protocol_parm, "RBC", 10) == 0 ||
3764 prot == USB_SC_RBC) {
3765 mod_data.protocol_type = USB_SC_RBC;
3766 mod_data.protocol_name = "RBC";
3767 } else if (strnicmp(mod_data.protocol_parm, "8020", 4) == 0 ||
3768 strnicmp(mod_data.protocol_parm, "ATAPI", 10) == 0 ||
3769 prot == USB_SC_8020) {
3770 mod_data.protocol_type = USB_SC_8020;
3771 mod_data.protocol_name = "8020i (ATAPI)";
3772 } else if (strnicmp(mod_data.protocol_parm, "QIC", 3) == 0 ||
3773 prot == USB_SC_QIC) {
3774 mod_data.protocol_type = USB_SC_QIC;
3775 mod_data.protocol_name = "QIC-157";
3776 } else if (strnicmp(mod_data.protocol_parm, "UFI", 10) == 0 ||
3777 prot == USB_SC_UFI) {
3778 mod_data.protocol_type = USB_SC_UFI;
3779 mod_data.protocol_name = "UFI";
3780 } else if (strnicmp(mod_data.protocol_parm, "8070", 4) == 0 ||
3781 prot == USB_SC_8070) {
3782 mod_data.protocol_type = USB_SC_8070;
3783 mod_data.protocol_name = "8070i";
3784 } else {
3785 ERROR(fsg, "invalid protocol: %s\n", mod_data.protocol_parm);
3786 return -EINVAL;
3789 mod_data.buflen &= PAGE_CACHE_MASK;
3790 if (mod_data.buflen <= 0) {
3791 ERROR(fsg, "invalid buflen\n");
3792 return -ETOOSMALL;
3794 #endif /* CONFIG_USB_FILE_STORAGE_TEST */
3796 return 0;
3800 static int __init fsg_bind(struct usb_gadget *gadget)
3802 struct fsg_dev *fsg = the_fsg;
3803 int rc;
3804 int i;
3805 struct lun *curlun;
3806 struct usb_ep *ep;
3807 struct usb_request *req;
3808 char *pathbuf, *p;
3810 fsg->gadget = gadget;
3811 set_gadget_data(gadget, fsg);
3812 fsg->ep0 = gadget->ep0;
3813 fsg->ep0->driver_data = fsg;
3815 if ((rc = check_parameters(fsg)) != 0)
3816 goto out;
3818 if (mod_data.removable) { // Enable the store_xxx attributes
3819 dev_attr_ro.attr.mode = dev_attr_file.attr.mode = 0644;
3820 dev_attr_ro.store = store_ro;
3821 dev_attr_file.store = store_file;
3824 /* Find out how many LUNs there should be */
3825 i = mod_data.nluns;
3826 if (i == 0)
3827 i = max(mod_data.num_filenames, 1u);
3828 if (i > MAX_LUNS) {
3829 ERROR(fsg, "invalid number of LUNs: %d\n", i);
3830 rc = -EINVAL;
3831 goto out;
3834 /* Create the LUNs, open their backing files, and register the
3835 * LUN devices in sysfs. */
3836 fsg->luns = kzalloc(i * sizeof(struct lun), GFP_KERNEL);
3837 if (!fsg->luns) {
3838 rc = -ENOMEM;
3839 goto out;
3841 fsg->nluns = i;
3843 for (i = 0; i < fsg->nluns; ++i) {
3844 curlun = &fsg->luns[i];
3845 curlun->ro = mod_data.ro[i];
3846 curlun->dev.release = lun_release;
3847 curlun->dev.parent = &gadget->dev;
3848 curlun->dev.driver = &fsg_driver.driver;
3849 dev_set_drvdata(&curlun->dev, fsg);
3850 snprintf(curlun->dev.bus_id, BUS_ID_SIZE,
3851 "%s-lun%d", gadget->dev.bus_id, i);
3853 if ((rc = device_register(&curlun->dev)) != 0) {
3854 INFO(fsg, "failed to register LUN%d: %d\n", i, rc);
3855 goto out;
3857 if ((rc = device_create_file(&curlun->dev,
3858 &dev_attr_ro)) != 0 ||
3859 (rc = device_create_file(&curlun->dev,
3860 &dev_attr_file)) != 0) {
3861 device_unregister(&curlun->dev);
3862 goto out;
3864 curlun->registered = 1;
3865 kref_get(&fsg->ref);
3867 if (mod_data.file[i] && *mod_data.file[i]) {
3868 if ((rc = open_backing_file(curlun,
3869 mod_data.file[i])) != 0)
3870 goto out;
3871 } else if (!mod_data.removable) {
3872 ERROR(fsg, "no file given for LUN%d\n", i);
3873 rc = -EINVAL;
3874 goto out;
3878 /* Find all the endpoints we will use */
3879 usb_ep_autoconfig_reset(gadget);
3880 ep = usb_ep_autoconfig(gadget, &fs_bulk_in_desc);
3881 if (!ep)
3882 goto autoconf_fail;
3883 ep->driver_data = fsg; // claim the endpoint
3884 fsg->bulk_in = ep;
3886 ep = usb_ep_autoconfig(gadget, &fs_bulk_out_desc);
3887 if (!ep)
3888 goto autoconf_fail;
3889 ep->driver_data = fsg; // claim the endpoint
3890 fsg->bulk_out = ep;
3892 if (transport_is_cbi()) {
3893 ep = usb_ep_autoconfig(gadget, &fs_intr_in_desc);
3894 if (!ep)
3895 goto autoconf_fail;
3896 ep->driver_data = fsg; // claim the endpoint
3897 fsg->intr_in = ep;
3900 /* Fix up the descriptors */
3901 device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
3902 device_desc.idVendor = cpu_to_le16(mod_data.vendor);
3903 device_desc.idProduct = cpu_to_le16(mod_data.product);
3904 device_desc.bcdDevice = cpu_to_le16(mod_data.release);
3906 i = (transport_is_cbi() ? 3 : 2); // Number of endpoints
3907 intf_desc.bNumEndpoints = i;
3908 intf_desc.bInterfaceSubClass = mod_data.protocol_type;
3909 intf_desc.bInterfaceProtocol = mod_data.transport_type;
3910 fs_function[i + FS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3912 if (gadget_is_dualspeed(gadget)) {
3913 hs_function[i + HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
3915 /* Assume ep0 uses the same maxpacket value for both speeds */
3916 dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
3918 /* Assume endpoint addresses are the same for both speeds */
3919 hs_bulk_in_desc.bEndpointAddress =
3920 fs_bulk_in_desc.bEndpointAddress;
3921 hs_bulk_out_desc.bEndpointAddress =
3922 fs_bulk_out_desc.bEndpointAddress;
3923 hs_intr_in_desc.bEndpointAddress =
3924 fs_intr_in_desc.bEndpointAddress;
3927 if (gadget_is_otg(gadget))
3928 otg_desc.bmAttributes |= USB_OTG_HNP;
3930 rc = -ENOMEM;
3932 /* Allocate the request and buffer for endpoint 0 */
3933 fsg->ep0req = req = usb_ep_alloc_request(fsg->ep0, GFP_KERNEL);
3934 if (!req)
3935 goto out;
3936 req->buf = kmalloc(EP0_BUFSIZE, GFP_KERNEL);
3937 if (!req->buf)
3938 goto out;
3939 req->complete = ep0_complete;
3941 /* Allocate the data buffers */
3942 for (i = 0; i < NUM_BUFFERS; ++i) {
3943 struct fsg_buffhd *bh = &fsg->buffhds[i];
3945 /* Allocate for the bulk-in endpoint. We assume that
3946 * the buffer will also work with the bulk-out (and
3947 * interrupt-in) endpoint. */
3948 bh->buf = kmalloc(mod_data.buflen, GFP_KERNEL);
3949 if (!bh->buf)
3950 goto out;
3951 bh->next = bh + 1;
3953 fsg->buffhds[NUM_BUFFERS - 1].next = &fsg->buffhds[0];
3955 /* This should reflect the actual gadget power source */
3956 usb_gadget_set_selfpowered(gadget);
3958 snprintf(manufacturer, sizeof manufacturer, "%s %s with %s",
3959 init_utsname()->sysname, init_utsname()->release,
3960 gadget->name);
3962 /* On a real device, serial[] would be loaded from permanent
3963 * storage. We just encode it from the driver version string. */
3964 for (i = 0; i < sizeof(serial) - 2; i += 2) {
3965 unsigned char c = DRIVER_VERSION[i / 2];
3967 if (!c)
3968 break;
3969 sprintf(&serial[i], "%02X", c);
3972 fsg->thread_task = kthread_create(fsg_main_thread, fsg,
3973 "file-storage-gadget");
3974 if (IS_ERR(fsg->thread_task)) {
3975 rc = PTR_ERR(fsg->thread_task);
3976 goto out;
3979 INFO(fsg, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
3980 INFO(fsg, "Number of LUNs=%d\n", fsg->nluns);
3982 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
3983 for (i = 0; i < fsg->nluns; ++i) {
3984 curlun = &fsg->luns[i];
3985 if (backing_file_is_open(curlun)) {
3986 p = NULL;
3987 if (pathbuf) {
3988 p = d_path(curlun->filp->f_path.dentry,
3989 curlun->filp->f_path.mnt,
3990 pathbuf, PATH_MAX);
3991 if (IS_ERR(p))
3992 p = NULL;
3994 LINFO(curlun, "ro=%d, file: %s\n",
3995 curlun->ro, (p ? p : "(error)"));
3998 kfree(pathbuf);
4000 DBG(fsg, "transport=%s (x%02x)\n",
4001 mod_data.transport_name, mod_data.transport_type);
4002 DBG(fsg, "protocol=%s (x%02x)\n",
4003 mod_data.protocol_name, mod_data.protocol_type);
4004 DBG(fsg, "VendorID=x%04x, ProductID=x%04x, Release=x%04x\n",
4005 mod_data.vendor, mod_data.product, mod_data.release);
4006 DBG(fsg, "removable=%d, stall=%d, buflen=%u\n",
4007 mod_data.removable, mod_data.can_stall,
4008 mod_data.buflen);
4009 DBG(fsg, "I/O thread pid: %d\n", task_pid_nr(fsg->thread_task));
4011 set_bit(REGISTERED, &fsg->atomic_bitflags);
4013 /* Tell the thread to start working */
4014 wake_up_process(fsg->thread_task);
4015 return 0;
4017 autoconf_fail:
4018 ERROR(fsg, "unable to autoconfigure all endpoints\n");
4019 rc = -ENOTSUPP;
4021 out:
4022 fsg->state = FSG_STATE_TERMINATED; // The thread is dead
4023 fsg_unbind(gadget);
4024 close_all_backing_files(fsg);
4025 return rc;
4029 /*-------------------------------------------------------------------------*/
4031 static void fsg_suspend(struct usb_gadget *gadget)
4033 struct fsg_dev *fsg = get_gadget_data(gadget);
4035 DBG(fsg, "suspend\n");
4036 set_bit(SUSPENDED, &fsg->atomic_bitflags);
4039 static void fsg_resume(struct usb_gadget *gadget)
4041 struct fsg_dev *fsg = get_gadget_data(gadget);
4043 DBG(fsg, "resume\n");
4044 clear_bit(SUSPENDED, &fsg->atomic_bitflags);
4048 /*-------------------------------------------------------------------------*/
4050 static struct usb_gadget_driver fsg_driver = {
4051 #ifdef CONFIG_USB_GADGET_DUALSPEED
4052 .speed = USB_SPEED_HIGH,
4053 #else
4054 .speed = USB_SPEED_FULL,
4055 #endif
4056 .function = (char *) longname,
4057 .bind = fsg_bind,
4058 .unbind = fsg_unbind,
4059 .disconnect = fsg_disconnect,
4060 .setup = fsg_setup,
4061 .suspend = fsg_suspend,
4062 .resume = fsg_resume,
4064 .driver = {
4065 .name = (char *) shortname,
4066 .owner = THIS_MODULE,
4067 // .release = ...
4068 // .suspend = ...
4069 // .resume = ...
4074 static int __init fsg_alloc(void)
4076 struct fsg_dev *fsg;
4078 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
4079 if (!fsg)
4080 return -ENOMEM;
4081 spin_lock_init(&fsg->lock);
4082 init_rwsem(&fsg->filesem);
4083 kref_init(&fsg->ref);
4084 init_completion(&fsg->thread_notifier);
4086 the_fsg = fsg;
4087 return 0;
4091 static int __init fsg_init(void)
4093 int rc;
4094 struct fsg_dev *fsg;
4096 if ((rc = fsg_alloc()) != 0)
4097 return rc;
4098 fsg = the_fsg;
4099 if ((rc = usb_gadget_register_driver(&fsg_driver)) != 0)
4100 kref_put(&fsg->ref, fsg_release);
4101 return rc;
4103 module_init(fsg_init);
4106 static void __exit fsg_cleanup(void)
4108 struct fsg_dev *fsg = the_fsg;
4110 /* Unregister the driver iff the thread hasn't already done so */
4111 if (test_and_clear_bit(REGISTERED, &fsg->atomic_bitflags))
4112 usb_gadget_unregister_driver(&fsg_driver);
4114 /* Wait for the thread to finish up */
4115 wait_for_completion(&fsg->thread_notifier);
4117 close_all_backing_files(fsg);
4118 kref_put(&fsg->ref, fsg_release);
4120 module_exit(fsg_cleanup);