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1/*
2 * f_mass_storage.c -- Mass Storage USB Composite Function
3 *
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The names of the above-listed copyright holders may not be used
19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
21 *
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
25 * later version.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
31 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
32 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
33 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
34 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * The Mass Storage Function acts as a USB Mass Storage device,
42 * appearing to the host as a disk drive or as a CD-ROM drive. In
43 * addition to providing an example of a genuinely useful composite
44 * function for a USB device, it also illustrates a technique of
45 * double-buffering for increased throughput.
46 *
47 * Function supports multiple logical units (LUNs). Backing storage
48 * for each LUN is provided by a regular file or a block device.
49 * Access for each LUN can be limited to read-only. Moreover, the
50 * function can indicate that LUN is removable and/or CD-ROM. (The
51 * later implies read-only access.)
52 *
53 * MSF is configured by specifying a fsg_config structure. It has the
54 * following fields:
55 *
56 * nluns Number of LUNs function have (anywhere from 1
57 * to FSG_MAX_LUNS which is 8).
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
65 * removable.
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
70 * in R/W mode.
71 * ->removable Flag specifying that LUN shall be indicated as
72 * being removable.
73 * ->cdrom Flag specifying that LUN shall be reported as
74 * being a CD-ROM.
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
77 *
78 * lun_name_format A printf-like format for names of the LUN
79 * devices. This determines how the
80 * directory in sysfs will be named.
81 * Unless you are using several MSFs in
82 * a single gadget (as opposed to single
83 * MSF in many configurations) you may
84 * leave it as NULL (in which case
85 * "lun%d" will be used). In the format
86 * you can use "%d" to index LUNs for
87 * MSF's with more than one LUN. (Beware
88 * that there is only one integer given
89 * as an argument for the format and
90 * specifying invalid format may cause
91 * unspecified behaviour.)
92 * thread_name Name of the kernel thread process used by the
93 * MSF. You can safely set it to NULL
94 * (in which case default "file-storage"
95 * will be used).
96 *
97 * vendor_name
98 * product_name
99 * release Information used as a reply to INQUIRY
100 * request. To use default set to NULL,
101 * NULL, 0xffff respectively. The first
102 * field should be 8 and the second 16
103 * characters or less.
104 *
105 * can_stall Set to permit function to halt bulk endpoints.
106 * Disabled on some USB devices known not
107 * to work correctly. You should set it
108 * to true.
109 *
110 * If "removable" is not set for a LUN then a backing file must be
111 * specified. If it is set, then NULL filename means the LUN's medium
112 * is not loaded (an empty string as "filename" in the fsg_config
113 * structure causes error). The CD-ROM emulation includes a single
114 * data track and no audio tracks; hence there need be only one
115 * backing file per LUN. Note also that the CD-ROM block length is
116 * set to 512 rather than the more common value 2048.
117 *
118 *
119 * MSF includes support for module parameters. If gadget using it
120 * decides to use it, the following module parameters will be
121 * available:
122 *
123 * file=filename[,filename...]
124 * Names of the files or block devices used for
125 * backing storage.
126 * ro=b[,b...] Default false, boolean for read-only access.
127 * removable=b[,b...]
128 * Default true, boolean for removable media.
129 * cdrom=b[,b...] Default false, boolean for whether to emulate
130 * a CD-ROM drive.
131 * nofua=b[,b...] Default false, booleans for ignore FUA flag
132 * in SCSI WRITE(10,12) commands
133 * luns=N Default N = number of filenames, number of
134 * LUNs to support.
135 * stall Default determined according to the type of
136 * USB device controller (usually true),
137 * boolean to permit the driver to halt
138 * bulk endpoints.
139 *
140 * The module parameters may be prefixed with some string. You need
141 * to consult gadget's documentation or source to verify whether it is
142 * using those module parameters and if it does what are the prefixes
143 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
144 * the prefix).
145 *
146 *
147 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
148 * needed. The memory requirement amounts to two 16K buffers, size
149 * configurable by a parameter. Support is included for both
150 * full-speed and high-speed operation.
151 *
152 * Note that the driver is slightly non-portable in that it assumes a
153 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
154 * interrupt-in endpoints. With most device controllers this isn't an
155 * issue, but there may be some with hardware restrictions that prevent
156 * a buffer from being used by more than one endpoint.
157 *
158 *
159 * The pathnames of the backing files and the ro settings are
160 * available in the attribute files "file" and "ro" in the lun<n> (or
161 * to be more precise in a directory which name comes from
162 * "lun_name_format" option!) subdirectory of the gadget's sysfs
163 * directory. If the "removable" option is set, writing to these
164 * files will simulate ejecting/loading the medium (writing an empty
165 * line means eject) and adjusting a write-enable tab. Changes to the
166 * ro setting are not allowed when the medium is loaded or if CD-ROM
167 * emulation is being used.
168 *
169 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
170 * if the LUN is removable, the backing file is released to simulate
171 * ejection.
172 *
173 *
174 * This function is heavily based on "File-backed Storage Gadget" by
175 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
176 * Brownell. The driver's SCSI command interface was based on the
177 * "Information technology - Small Computer System Interface - 2"
178 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
179 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
180 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
181 * was based on the "Universal Serial Bus Mass Storage Class UFI
182 * Command Specification" document, Revision 1.0, December 14, 1998,
183 * available at
184 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
185 */
186
187/*
188 * Driver Design
189 *
190 * The MSF is fairly straightforward. There is a main kernel
191 * thread that handles most of the work. Interrupt routines field
192 * callbacks from the controller driver: bulk- and interrupt-request
193 * completion notifications, endpoint-0 events, and disconnect events.
194 * Completion events are passed to the main thread by wakeup calls. Many
195 * ep0 requests are handled at interrupt time, but SetInterface,
196 * SetConfiguration, and device reset requests are forwarded to the
197 * thread in the form of "exceptions" using SIGUSR1 signals (since they
198 * should interrupt any ongoing file I/O operations).
199 *
200 * The thread's main routine implements the standard command/data/status
201 * parts of a SCSI interaction. It and its subroutines are full of tests
202 * for pending signals/exceptions -- all this polling is necessary since
203 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
204 * indication that the driver really wants to be running in userspace.)
205 * An important point is that so long as the thread is alive it keeps an
206 * open reference to the backing file. This will prevent unmounting
207 * the backing file's underlying filesystem and could cause problems
208 * during system shutdown, for example. To prevent such problems, the
209 * thread catches INT, TERM, and KILL signals and converts them into
210 * an EXIT exception.
211 *
212 * In normal operation the main thread is started during the gadget's
213 * fsg_bind() callback and stopped during fsg_unbind(). But it can
214 * also exit when it receives a signal, and there's no point leaving
215 * the gadget running when the thread is dead. At of this moment, MSF
216 * provides no way to deregister the gadget when thread dies -- maybe
217 * a callback functions is needed.
218 *
219 * To provide maximum throughput, the driver uses a circular pipeline of
220 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
221 * arbitrarily long; in practice the benefits don't justify having more
222 * than 2 stages (i.e., double buffering). But it helps to think of the
223 * pipeline as being a long one. Each buffer head contains a bulk-in and
224 * a bulk-out request pointer (since the buffer can be used for both
225 * output and input -- directions always are given from the host's
226 * point of view) as well as a pointer to the buffer and various state
227 * variables.
228 *
229 * Use of the pipeline follows a simple protocol. There is a variable
230 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
231 * At any time that buffer head may still be in use from an earlier
232 * request, so each buffer head has a state variable indicating whether
233 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
234 * buffer head to be EMPTY, filling the buffer either by file I/O or by
235 * USB I/O (during which the buffer head is BUSY), and marking the buffer
236 * head FULL when the I/O is complete. Then the buffer will be emptied
237 * (again possibly by USB I/O, during which it is marked BUSY) and
238 * finally marked EMPTY again (possibly by a completion routine).
239 *
240 * A module parameter tells the driver to avoid stalling the bulk
241 * endpoints wherever the transport specification allows. This is
242 * necessary for some UDCs like the SuperH, which cannot reliably clear a
243 * halt on a bulk endpoint. However, under certain circumstances the
244 * Bulk-only specification requires a stall. In such cases the driver
245 * will halt the endpoint and set a flag indicating that it should clear
246 * the halt in software during the next device reset. Hopefully this
247 * will permit everything to work correctly. Furthermore, although the
248 * specification allows the bulk-out endpoint to halt when the host sends
249 * too much data, implementing this would cause an unavoidable race.
250 * The driver will always use the "no-stall" approach for OUT transfers.
251 *
252 * One subtle point concerns sending status-stage responses for ep0
253 * requests. Some of these requests, such as device reset, can involve
254 * interrupting an ongoing file I/O operation, which might take an
255 * arbitrarily long time. During that delay the host might give up on
256 * the original ep0 request and issue a new one. When that happens the
257 * driver should not notify the host about completion of the original
258 * request, as the host will no longer be waiting for it. So the driver
259 * assigns to each ep0 request a unique tag, and it keeps track of the
260 * tag value of the request associated with a long-running exception
261 * (device-reset, interface-change, or configuration-change). When the
262 * exception handler is finished, the status-stage response is submitted
263 * only if the current ep0 request tag is equal to the exception request
264 * tag. Thus only the most recently received ep0 request will get a
265 * status-stage response.
266 *
267 * Warning: This driver source file is too long. It ought to be split up
268 * into a header file plus about 3 separate .c files, to handle the details
269 * of the Gadget, USB Mass Storage, and SCSI protocols.
270 */
271
272
273/* #define VERBOSE_DEBUG */
274/* #define DUMP_MSGS */
275
276#include <linux/blkdev.h>
277#include <linux/completion.h>
278#include <linux/dcache.h>
279#include <linux/delay.h>
280#include <linux/device.h>
281#include <linux/fcntl.h>
282#include <linux/file.h>
283#include <linux/fs.h>
284#include <linux/kref.h>
285#include <linux/kthread.h>
286#include <linux/limits.h>
287#include <linux/rwsem.h>
288#include <linux/slab.h>
289#include <linux/spinlock.h>
290#include <linux/string.h>
291#include <linux/freezer.h>
292#include <linux/utsname.h>
293
294#include <linux/usb/ch9.h>
295#include <linux/usb/gadget.h>
296#include <linux/usb/composite.h>
297
298#include "gadget_chips.h"
299
300
301/*------------------------------------------------------------------------*/
302
303#define FSG_DRIVER_DESC "Mass Storage Function"
304#define FSG_DRIVER_VERSION "2009/09/11"
305
306static const char fsg_string_interface[] = "Mass Storage";
307
308#define FSG_NO_INTR_EP 1
309#define FSG_NO_DEVICE_STRINGS 1
310#define FSG_NO_OTG 1
311#define FSG_NO_INTR_EP 1
312
313#include "storage_common.c"
314
315
316/*-------------------------------------------------------------------------*/
317
318struct fsg_dev;
319struct fsg_common;
320
321/* FSF callback functions */
322struct fsg_operations {
323 /*
324 * Callback function to call when thread exits. If no
325 * callback is set or it returns value lower then zero MSF
326 * will force eject all LUNs it operates on (including those
327 * marked as non-removable or with prevent_medium_removal flag
328 * set).
329 */
330 int (*thread_exits)(struct fsg_common *common);
331
332 /*
333 * Called prior to ejection. Negative return means error,
334 * zero means to continue with ejection, positive means not to
335 * eject.
336 */
337 int (*pre_eject)(struct fsg_common *common,
338 struct fsg_lun *lun, int num);
339 /*
340 * Called after ejection. Negative return means error, zero
341 * or positive is just a success.
342 */
343 int (*post_eject)(struct fsg_common *common,
344 struct fsg_lun *lun, int num);
345};
346
347/* Data shared by all the FSG instances. */
348struct fsg_common {
349 struct usb_gadget *gadget;
350 struct usb_composite_dev *cdev;
351 struct fsg_dev *fsg, *new_fsg;
352 wait_queue_head_t fsg_wait;
353
354 /* filesem protects: backing files in use */
355 struct rw_semaphore filesem;
356
357 /* lock protects: state, all the req_busy's */
358 spinlock_t lock;
359
360 struct usb_ep *ep0; /* Copy of gadget->ep0 */
361 struct usb_request *ep0req; /* Copy of cdev->req */
362 unsigned int ep0_req_tag;
363
364 struct fsg_buffhd *next_buffhd_to_fill;
365 struct fsg_buffhd *next_buffhd_to_drain;
366 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
367
368 int cmnd_size;
369 u8 cmnd[MAX_COMMAND_SIZE];
370
371 unsigned int nluns;
372 unsigned int lun;
373 struct fsg_lun *luns;
374 struct fsg_lun *curlun;
375
376 unsigned int bulk_out_maxpacket;
377 enum fsg_state state; /* For exception handling */
378 unsigned int exception_req_tag;
379
380 enum data_direction data_dir;
381 u32 data_size;
382 u32 data_size_from_cmnd;
383 u32 tag;
384 u32 residue;
385 u32 usb_amount_left;
386
387 unsigned int can_stall:1;
388 unsigned int free_storage_on_release:1;
389 unsigned int phase_error:1;
390 unsigned int short_packet_received:1;
391 unsigned int bad_lun_okay:1;
392 unsigned int running:1;
393
394 int thread_wakeup_needed;
395 struct completion thread_notifier;
396 struct task_struct *thread_task;
397
398 /* Callback functions. */
399 const struct fsg_operations *ops;
400 /* Gadget's private data. */
401 void *private_data;
402
403 /*
404 * Vendor (8 chars), product (16 chars), release (4
405 * hexadecimal digits) and NUL byte
406 */
407 char inquiry_string[8 + 16 + 4 + 1];
408
409 struct kref ref;
410};
411
412struct fsg_config {
413 unsigned nluns;
414 struct fsg_lun_config {
415 const char *filename;
416 char ro;
417 char removable;
418 char cdrom;
419 char nofua;
420 } luns[FSG_MAX_LUNS];
421
422 const char *lun_name_format;
423 const char *thread_name;
424
425 /* Callback functions. */
426 const struct fsg_operations *ops;
427 /* Gadget's private data. */
428 void *private_data;
429
430 const char *vendor_name; /* 8 characters or less */
431 const char *product_name; /* 16 characters or less */
432 u16 release;
433
434 char can_stall;
435};
436
437struct fsg_dev {
438 struct usb_function function;
439 struct usb_gadget *gadget; /* Copy of cdev->gadget */
440 struct fsg_common *common;
441
442 u16 interface_number;
443
444 unsigned int bulk_in_enabled:1;
445 unsigned int bulk_out_enabled:1;
446
447 unsigned long atomic_bitflags;
448#define IGNORE_BULK_OUT 0
449
450 struct usb_ep *bulk_in;
451 struct usb_ep *bulk_out;
452};
453
454static inline int __fsg_is_set(struct fsg_common *common,
455 const char *func, unsigned line)
456{
457 if (common->fsg)
458 return 1;
459 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
460 WARN_ON(1);
461 return 0;
462}
463
464#define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
465
466static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
467{
468 return container_of(f, struct fsg_dev, function);
469}
470
471typedef void (*fsg_routine_t)(struct fsg_dev *);
472
473static int exception_in_progress(struct fsg_common *common)
474{
475 return common->state > FSG_STATE_IDLE;
476}
477
478/* Make bulk-out requests be divisible by the maxpacket size */
479static void set_bulk_out_req_length(struct fsg_common *common,
480 struct fsg_buffhd *bh, unsigned int length)
481{
482 unsigned int rem;
483
484 bh->bulk_out_intended_length = length;
485 rem = length % common->bulk_out_maxpacket;
486 if (rem > 0)
487 length += common->bulk_out_maxpacket - rem;
488 bh->outreq->length = length;
489}
490
491
492/*-------------------------------------------------------------------------*/
493
494static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
495{
496 const char *name;
497
498 if (ep == fsg->bulk_in)
499 name = "bulk-in";
500 else if (ep == fsg->bulk_out)
501 name = "bulk-out";
502 else
503 name = ep->name;
504 DBG(fsg, "%s set halt\n", name);
505 return usb_ep_set_halt(ep);
506}
507
508
509/*-------------------------------------------------------------------------*/
510
511/* These routines may be called in process context or in_irq */
512
513/* Caller must hold fsg->lock */
514static void wakeup_thread(struct fsg_common *common)
515{
516 /* Tell the main thread that something has happened */
517 common->thread_wakeup_needed = 1;
518 if (common->thread_task)
519 wake_up_process(common->thread_task);
520}
521
522static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
523{
524 unsigned long flags;
525
526 /*
527 * Do nothing if a higher-priority exception is already in progress.
528 * If a lower-or-equal priority exception is in progress, preempt it
529 * and notify the main thread by sending it a signal.
530 */
531 spin_lock_irqsave(&common->lock, flags);
532 if (common->state <= new_state) {
533 common->exception_req_tag = common->ep0_req_tag;
534 common->state = new_state;
535 if (common->thread_task)
536 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
537 common->thread_task);
538 }
539 spin_unlock_irqrestore(&common->lock, flags);
540}
541
542
543/*-------------------------------------------------------------------------*/
544
545static int ep0_queue(struct fsg_common *common)
546{
547 int rc;
548
549 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
550 common->ep0->driver_data = common;
551 if (rc != 0 && rc != -ESHUTDOWN) {
552 /* We can't do much more than wait for a reset */
553 WARNING(common, "error in submission: %s --> %d\n",
554 common->ep0->name, rc);
555 }
556 return rc;
557}
558
559
560/*-------------------------------------------------------------------------*/
561
562/* Completion handlers. These always run in_irq. */
563
564static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
565{
566 struct fsg_common *common = ep->driver_data;
567 struct fsg_buffhd *bh = req->context;
568
569 if (req->status || req->actual != req->length)
570 DBG(common, "%s --> %d, %u/%u\n", __func__,
571 req->status, req->actual, req->length);
572 if (req->status == -ECONNRESET) /* Request was cancelled */
573 usb_ep_fifo_flush(ep);
574
575 /* Hold the lock while we update the request and buffer states */
576 smp_wmb();
577 spin_lock(&common->lock);
578 bh->inreq_busy = 0;
579 bh->state = BUF_STATE_EMPTY;
580 wakeup_thread(common);
581 spin_unlock(&common->lock);
582}
583
584static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
585{
586 struct fsg_common *common = ep->driver_data;
587 struct fsg_buffhd *bh = req->context;
588
589 dump_msg(common, "bulk-out", req->buf, req->actual);
590 if (req->status || req->actual != bh->bulk_out_intended_length)
591 DBG(common, "%s --> %d, %u/%u\n", __func__,
592 req->status, req->actual, bh->bulk_out_intended_length);
593 if (req->status == -ECONNRESET) /* Request was cancelled */
594 usb_ep_fifo_flush(ep);
595
596 /* Hold the lock while we update the request and buffer states */
597 smp_wmb();
598 spin_lock(&common->lock);
599 bh->outreq_busy = 0;
600 bh->state = BUF_STATE_FULL;
601 wakeup_thread(common);
602 spin_unlock(&common->lock);
603}
604
605static int fsg_setup(struct usb_function *f,
606 const struct usb_ctrlrequest *ctrl)
607{
608 struct fsg_dev *fsg = fsg_from_func(f);
609 struct usb_request *req = fsg->common->ep0req;
610 u16 w_index = le16_to_cpu(ctrl->wIndex);
611 u16 w_value = le16_to_cpu(ctrl->wValue);
612 u16 w_length = le16_to_cpu(ctrl->wLength);
613
614 if (!fsg_is_set(fsg->common))
615 return -EOPNOTSUPP;
616
617 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
618 req->context = NULL;
619 req->length = 0;
620 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
621
622 switch (ctrl->bRequest) {
623
624 case USB_BULK_RESET_REQUEST:
625 if (ctrl->bRequestType !=
626 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
627 break;
628 if (w_index != fsg->interface_number || w_value != 0)
629 return -EDOM;
630
631 /*
632 * Raise an exception to stop the current operation
633 * and reinitialize our state.
634 */
635 DBG(fsg, "bulk reset request\n");
636 raise_exception(fsg->common, FSG_STATE_RESET);
637 return DELAYED_STATUS;
638
639 case USB_BULK_GET_MAX_LUN_REQUEST:
640 if (ctrl->bRequestType !=
641 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
642 break;
643 if (w_index != fsg->interface_number || w_value != 0)
644 return -EDOM;
645 VDBG(fsg, "get max LUN\n");
646 *(u8 *)req->buf = fsg->common->nluns - 1;
647
648 /* Respond with data/status */
649 req->length = min((u16)1, w_length);
650 return ep0_queue(fsg->common);
651 }
652
653 VDBG(fsg,
654 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
655 ctrl->bRequestType, ctrl->bRequest,
656 le16_to_cpu(ctrl->wValue), w_index, w_length);
657 return -EOPNOTSUPP;
658}
659
660
661/*-------------------------------------------------------------------------*/
662
663/* All the following routines run in process context */
664
665/* Use this for bulk or interrupt transfers, not ep0 */
666static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
667 struct usb_request *req, int *pbusy,
668 enum fsg_buffer_state *state)
669{
670 int rc;
671
672 if (ep == fsg->bulk_in)
673 dump_msg(fsg, "bulk-in", req->buf, req->length);
674
675 spin_lock_irq(&fsg->common->lock);
676 *pbusy = 1;
677 *state = BUF_STATE_BUSY;
678 spin_unlock_irq(&fsg->common->lock);
679 rc = usb_ep_queue(ep, req, GFP_KERNEL);
680 if (rc != 0) {
681 *pbusy = 0;
682 *state = BUF_STATE_EMPTY;
683
684 /* We can't do much more than wait for a reset */
685
686 /*
687 * Note: currently the net2280 driver fails zero-length
688 * submissions if DMA is enabled.
689 */
690 if (rc != -ESHUTDOWN &&
691 !(rc == -EOPNOTSUPP && req->length == 0))
692 WARNING(fsg, "error in submission: %s --> %d\n",
693 ep->name, rc);
694 }
695}
696
697static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
698{
699 if (!fsg_is_set(common))
700 return false;
701 start_transfer(common->fsg, common->fsg->bulk_in,
702 bh->inreq, &bh->inreq_busy, &bh->state);
703 return true;
704}
705
706static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
707{
708 if (!fsg_is_set(common))
709 return false;
710 start_transfer(common->fsg, common->fsg->bulk_out,
711 bh->outreq, &bh->outreq_busy, &bh->state);
712 return true;
713}
714
715static int sleep_thread(struct fsg_common *common)
716{
717 int rc = 0;
718
719 /* Wait until a signal arrives or we are woken up */
720 for (;;) {
721 try_to_freeze();
722 set_current_state(TASK_INTERRUPTIBLE);
723 if (signal_pending(current)) {
724 rc = -EINTR;
725 break;
726 }
727 if (common->thread_wakeup_needed)
728 break;
729 schedule();
730 }
731 __set_current_state(TASK_RUNNING);
732 common->thread_wakeup_needed = 0;
733 return rc;
734}
735
736
737/*-------------------------------------------------------------------------*/
738
739static int do_read(struct fsg_common *common)
740{
741 struct fsg_lun *curlun = common->curlun;
742 u32 lba;
743 struct fsg_buffhd *bh;
744 int rc;
745 u32 amount_left;
746 loff_t file_offset, file_offset_tmp;
747 unsigned int amount;
748 unsigned int partial_page;
749 ssize_t nread;
750
751 /*
752 * Get the starting Logical Block Address and check that it's
753 * not too big.
754 */
755 if (common->cmnd[0] == READ_6)
756 lba = get_unaligned_be24(&common->cmnd[1]);
757 else {
758 lba = get_unaligned_be32(&common->cmnd[2]);
759
760 /*
761 * We allow DPO (Disable Page Out = don't save data in the
762 * cache) and FUA (Force Unit Access = don't read from the
763 * cache), but we don't implement them.
764 */
765 if ((common->cmnd[1] & ~0x18) != 0) {
766 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
767 return -EINVAL;
768 }
769 }
770 if (lba >= curlun->num_sectors) {
771 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
772 return -EINVAL;
773 }
774 file_offset = ((loff_t) lba) << 9;
775
776 /* Carry out the file reads */
777 amount_left = common->data_size_from_cmnd;
778 if (unlikely(amount_left == 0))
779 return -EIO; /* No default reply */
780
781 for (;;) {
782 /*
783 * Figure out how much we need to read:
784 * Try to read the remaining amount.
785 * But don't read more than the buffer size.
786 * And don't try to read past the end of the file.
787 * Finally, if we're not at a page boundary, don't read past
788 * the next page.
789 * If this means reading 0 then we were asked to read past
790 * the end of file.
791 */
792 amount = min(amount_left, FSG_BUFLEN);
793 amount = min((loff_t)amount,
794 curlun->file_length - file_offset);
795 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
796 if (partial_page > 0)
797 amount = min(amount, (unsigned int)PAGE_CACHE_SIZE -
798 partial_page);
799
800 /* Wait for the next buffer to become available */
801 bh = common->next_buffhd_to_fill;
802 while (bh->state != BUF_STATE_EMPTY) {
803 rc = sleep_thread(common);
804 if (rc)
805 return rc;
806 }
807
808 /*
809 * If we were asked to read past the end of file,
810 * end with an empty buffer.
811 */
812 if (amount == 0) {
813 curlun->sense_data =
814 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
815 curlun->sense_data_info = file_offset >> 9;
816 curlun->info_valid = 1;
817 bh->inreq->length = 0;
818 bh->state = BUF_STATE_FULL;
819 break;
820 }
821
822 /* Perform the read */
823 file_offset_tmp = file_offset;
824 nread = vfs_read(curlun->filp,
825 (char __user *)bh->buf,
826 amount, &file_offset_tmp);
827 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
828 (unsigned long long)file_offset, (int)nread);
829 if (signal_pending(current))
830 return -EINTR;
831
832 if (nread < 0) {
833 LDBG(curlun, "error in file read: %d\n", (int)nread);
834 nread = 0;
835 } else if (nread < amount) {
836 LDBG(curlun, "partial file read: %d/%u\n",
837 (int)nread, amount);
838 nread -= (nread & 511); /* Round down to a block */
839 }
840 file_offset += nread;
841 amount_left -= nread;
842 common->residue -= nread;
843 bh->inreq->length = nread;
844 bh->state = BUF_STATE_FULL;
845
846 /* If an error occurred, report it and its position */
847 if (nread < amount) {
848 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
849 curlun->sense_data_info = file_offset >> 9;
850 curlun->info_valid = 1;
851 break;
852 }
853
854 if (amount_left == 0)
855 break; /* No more left to read */
856
857 /* Send this buffer and go read some more */
858 bh->inreq->zero = 0;
859 if (!start_in_transfer(common, bh))
860 /* Don't know what to do if common->fsg is NULL */
861 return -EIO;
862 common->next_buffhd_to_fill = bh->next;
863 }
864
865 return -EIO; /* No default reply */
866}
867
868
869/*-------------------------------------------------------------------------*/
870
871static int do_write(struct fsg_common *common)
872{
873 struct fsg_lun *curlun = common->curlun;
874 u32 lba;
875 struct fsg_buffhd *bh;
876 int get_some_more;
877 u32 amount_left_to_req, amount_left_to_write;
878 loff_t usb_offset, file_offset, file_offset_tmp;
879 unsigned int amount;
880 unsigned int partial_page;
881 ssize_t nwritten;
882 int rc;
883
884 if (curlun->ro) {
885 curlun->sense_data = SS_WRITE_PROTECTED;
886 return -EINVAL;
887 }
888 spin_lock(&curlun->filp->f_lock);
889 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
890 spin_unlock(&curlun->filp->f_lock);
891
892 /*
893 * Get the starting Logical Block Address and check that it's
894 * not too big
895 */
896 if (common->cmnd[0] == WRITE_6)
897 lba = get_unaligned_be24(&common->cmnd[1]);
898 else {
899 lba = get_unaligned_be32(&common->cmnd[2]);
900
901 /*
902 * We allow DPO (Disable Page Out = don't save data in the
903 * cache) and FUA (Force Unit Access = write directly to the
904 * medium). We don't implement DPO; we implement FUA by
905 * performing synchronous output.
906 */
907 if (common->cmnd[1] & ~0x18) {
908 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
909 return -EINVAL;
910 }
911 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
912 spin_lock(&curlun->filp->f_lock);
913 curlun->filp->f_flags |= O_SYNC;
914 spin_unlock(&curlun->filp->f_lock);
915 }
916 }
917 if (lba >= curlun->num_sectors) {
918 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
919 return -EINVAL;
920 }
921
922 /* Carry out the file writes */
923 get_some_more = 1;
924 file_offset = usb_offset = ((loff_t) lba) << 9;
925 amount_left_to_req = common->data_size_from_cmnd;
926 amount_left_to_write = common->data_size_from_cmnd;
927
928 while (amount_left_to_write > 0) {
929
930 /* Queue a request for more data from the host */
931 bh = common->next_buffhd_to_fill;
932 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
933
934 /*
935 * Figure out how much we want to get:
936 * Try to get the remaining amount.
937 * But don't get more than the buffer size.
938 * And don't try to go past the end of the file.
939 * If we're not at a page boundary,
940 * don't go past the next page.
941 * If this means getting 0, then we were asked
942 * to write past the end of file.
943 * Finally, round down to a block boundary.
944 */
945 amount = min(amount_left_to_req, FSG_BUFLEN);
946 amount = min((loff_t)amount,
947 curlun->file_length - usb_offset);
948 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
949 if (partial_page > 0)
950 amount = min(amount,
951 (unsigned int)PAGE_CACHE_SIZE - partial_page);
952
953 if (amount == 0) {
954 get_some_more = 0;
955 curlun->sense_data =
956 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
957 curlun->sense_data_info = usb_offset >> 9;
958 curlun->info_valid = 1;
959 continue;
960 }
961 amount -= amount & 511;
962 if (amount == 0) {
963
964 /*
965 * Why were we were asked to transfer a
966 * partial block?
967 */
968 get_some_more = 0;
969 continue;
970 }
971
972 /* Get the next buffer */
973 usb_offset += amount;
974 common->usb_amount_left -= amount;
975 amount_left_to_req -= amount;
976 if (amount_left_to_req == 0)
977 get_some_more = 0;
978
979 /*
980 * amount is always divisible by 512, hence by
981 * the bulk-out maxpacket size
982 */
983 bh->outreq->length = amount;
984 bh->bulk_out_intended_length = amount;
985 bh->outreq->short_not_ok = 1;
986 if (!start_out_transfer(common, bh))
987 /* Dunno what to do if common->fsg is NULL */
988 return -EIO;
989 common->next_buffhd_to_fill = bh->next;
990 continue;
991 }
992
993 /* Write the received data to the backing file */
994 bh = common->next_buffhd_to_drain;
995 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
996 break; /* We stopped early */
997 if (bh->state == BUF_STATE_FULL) {
998 smp_rmb();
999 common->next_buffhd_to_drain = bh->next;
1000 bh->state = BUF_STATE_EMPTY;
1001
1002 /* Did something go wrong with the transfer? */
1003 if (bh->outreq->status != 0) {
1004 curlun->sense_data = SS_COMMUNICATION_FAILURE;
1005 curlun->sense_data_info = file_offset >> 9;
1006 curlun->info_valid = 1;
1007 break;
1008 }
1009
1010 amount = bh->outreq->actual;
1011 if (curlun->file_length - file_offset < amount) {
1012 LERROR(curlun,
1013 "write %u @ %llu beyond end %llu\n",
1014 amount, (unsigned long long)file_offset,
1015 (unsigned long long)curlun->file_length);
1016 amount = curlun->file_length - file_offset;
1017 }
1018
1019 /* Perform the write */
1020 file_offset_tmp = file_offset;
1021 nwritten = vfs_write(curlun->filp,
1022 (char __user *)bh->buf,
1023 amount, &file_offset_tmp);
1024 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
1025 (unsigned long long)file_offset, (int)nwritten);
1026 if (signal_pending(current))
1027 return -EINTR; /* Interrupted! */
1028
1029 if (nwritten < 0) {
1030 LDBG(curlun, "error in file write: %d\n",
1031 (int)nwritten);
1032 nwritten = 0;
1033 } else if (nwritten < amount) {
1034 LDBG(curlun, "partial file write: %d/%u\n",
1035 (int)nwritten, amount);
1036 nwritten -= (nwritten & 511);
1037 /* Round down to a block */
1038 }
1039 file_offset += nwritten;
1040 amount_left_to_write -= nwritten;
1041 common->residue -= nwritten;
1042
1043 /* If an error occurred, report it and its position */
1044 if (nwritten < amount) {
1045 curlun->sense_data = SS_WRITE_ERROR;
1046 curlun->sense_data_info = file_offset >> 9;
1047 curlun->info_valid = 1;
1048 break;
1049 }
1050
1051 /* Did the host decide to stop early? */
1052 if (bh->outreq->actual != bh->outreq->length) {
1053 common->short_packet_received = 1;
1054 break;
1055 }
1056 continue;
1057 }
1058
1059 /* Wait for something to happen */
1060 rc = sleep_thread(common);
1061 if (rc)
1062 return rc;
1063 }
1064
1065 return -EIO; /* No default reply */
1066}
1067
1068
1069/*-------------------------------------------------------------------------*/
1070
1071static int do_synchronize_cache(struct fsg_common *common)
1072{
1073 struct fsg_lun *curlun = common->curlun;
1074 int rc;
1075
1076 /* We ignore the requested LBA and write out all file's
1077 * dirty data buffers. */
1078 rc = fsg_lun_fsync_sub(curlun);
1079 if (rc)
1080 curlun->sense_data = SS_WRITE_ERROR;
1081 return 0;
1082}
1083
1084
1085/*-------------------------------------------------------------------------*/
1086
1087static void invalidate_sub(struct fsg_lun *curlun)
1088{
1089 struct file *filp = curlun->filp;
1090 struct inode *inode = filp->f_path.dentry->d_inode;
1091 unsigned long rc;
1092
1093 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1094 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1095}
1096
1097static int do_verify(struct fsg_common *common)
1098{
1099 struct fsg_lun *curlun = common->curlun;
1100 u32 lba;
1101 u32 verification_length;
1102 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1103 loff_t file_offset, file_offset_tmp;
1104 u32 amount_left;
1105 unsigned int amount;
1106 ssize_t nread;
1107
1108 /*
1109 * Get the starting Logical Block Address and check that it's
1110 * not too big.
1111 */
1112 lba = get_unaligned_be32(&common->cmnd[2]);
1113 if (lba >= curlun->num_sectors) {
1114 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1115 return -EINVAL;
1116 }
1117
1118 /*
1119 * We allow DPO (Disable Page Out = don't save data in the
1120 * cache) but we don't implement it.
1121 */
1122 if (common->cmnd[1] & ~0x10) {
1123 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1124 return -EINVAL;
1125 }
1126
1127 verification_length = get_unaligned_be16(&common->cmnd[7]);
1128 if (unlikely(verification_length == 0))
1129 return -EIO; /* No default reply */
1130
1131 /* Prepare to carry out the file verify */
1132 amount_left = verification_length << 9;
1133 file_offset = ((loff_t) lba) << 9;
1134
1135 /* Write out all the dirty buffers before invalidating them */
1136 fsg_lun_fsync_sub(curlun);
1137 if (signal_pending(current))
1138 return -EINTR;
1139
1140 invalidate_sub(curlun);
1141 if (signal_pending(current))
1142 return -EINTR;
1143
1144 /* Just try to read the requested blocks */
1145 while (amount_left > 0) {
1146 /*
1147 * Figure out how much we need to read:
1148 * Try to read the remaining amount, but not more than
1149 * the buffer size.
1150 * And don't try to read past the end of the file.
1151 * If this means reading 0 then we were asked to read
1152 * past the end of file.
1153 */
1154 amount = min(amount_left, FSG_BUFLEN);
1155 amount = min((loff_t)amount,
1156 curlun->file_length - file_offset);
1157 if (amount == 0) {
1158 curlun->sense_data =
1159 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1160 curlun->sense_data_info = file_offset >> 9;
1161 curlun->info_valid = 1;
1162 break;
1163 }
1164
1165 /* Perform the read */
1166 file_offset_tmp = file_offset;
1167 nread = vfs_read(curlun->filp,
1168 (char __user *) bh->buf,
1169 amount, &file_offset_tmp);
1170 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1171 (unsigned long long) file_offset,
1172 (int) nread);
1173 if (signal_pending(current))
1174 return -EINTR;
1175
1176 if (nread < 0) {
1177 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1178 nread = 0;
1179 } else if (nread < amount) {
1180 LDBG(curlun, "partial file verify: %d/%u\n",
1181 (int)nread, amount);
1182 nread -= nread & 511; /* Round down to a sector */
1183 }
1184 if (nread == 0) {
1185 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1186 curlun->sense_data_info = file_offset >> 9;
1187 curlun->info_valid = 1;
1188 break;
1189 }
1190 file_offset += nread;
1191 amount_left -= nread;
1192 }
1193 return 0;
1194}
1195
1196
1197/*-------------------------------------------------------------------------*/
1198
1199static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1200{
1201 struct fsg_lun *curlun = common->curlun;
1202 u8 *buf = (u8 *) bh->buf;
1203
1204 if (!curlun) { /* Unsupported LUNs are okay */
1205 common->bad_lun_okay = 1;
1206 memset(buf, 0, 36);
1207 buf[0] = 0x7f; /* Unsupported, no device-type */
1208 buf[4] = 31; /* Additional length */
1209 return 36;
1210 }
1211
1212 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1213 buf[1] = curlun->removable ? 0x80 : 0;
1214 buf[2] = 2; /* ANSI SCSI level 2 */
1215 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1216 buf[4] = 31; /* Additional length */
1217 buf[5] = 0; /* No special options */
1218 buf[6] = 0;
1219 buf[7] = 0;
1220 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1221 return 36;
1222}
1223
1224static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1225{
1226 struct fsg_lun *curlun = common->curlun;
1227 u8 *buf = (u8 *) bh->buf;
1228 u32 sd, sdinfo;
1229 int valid;
1230
1231 /*
1232 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1233 *
1234 * If a REQUEST SENSE command is received from an initiator
1235 * with a pending unit attention condition (before the target
1236 * generates the contingent allegiance condition), then the
1237 * target shall either:
1238 * a) report any pending sense data and preserve the unit
1239 * attention condition on the logical unit, or,
1240 * b) report the unit attention condition, may discard any
1241 * pending sense data, and clear the unit attention
1242 * condition on the logical unit for that initiator.
1243 *
1244 * FSG normally uses option a); enable this code to use option b).
1245 */
1246#if 0
1247 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1248 curlun->sense_data = curlun->unit_attention_data;
1249 curlun->unit_attention_data = SS_NO_SENSE;
1250 }
1251#endif
1252
1253 if (!curlun) { /* Unsupported LUNs are okay */
1254 common->bad_lun_okay = 1;
1255 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1256 sdinfo = 0;
1257 valid = 0;
1258 } else {
1259 sd = curlun->sense_data;
1260 sdinfo = curlun->sense_data_info;
1261 valid = curlun->info_valid << 7;
1262 curlun->sense_data = SS_NO_SENSE;
1263 curlun->sense_data_info = 0;
1264 curlun->info_valid = 0;
1265 }
1266
1267 memset(buf, 0, 18);
1268 buf[0] = valid | 0x70; /* Valid, current error */
1269 buf[2] = SK(sd);
1270 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1271 buf[7] = 18 - 8; /* Additional sense length */
1272 buf[12] = ASC(sd);
1273 buf[13] = ASCQ(sd);
1274 return 18;
1275}
1276
1277static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1278{
1279 struct fsg_lun *curlun = common->curlun;
1280 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1281 int pmi = common->cmnd[8];
1282 u8 *buf = (u8 *)bh->buf;
1283
1284 /* Check the PMI and LBA fields */
1285 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1286 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1287 return -EINVAL;
1288 }
1289
1290 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1291 /* Max logical block */
1292 put_unaligned_be32(512, &buf[4]); /* Block length */
1293 return 8;
1294}
1295
1296static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1297{
1298 struct fsg_lun *curlun = common->curlun;
1299 int msf = common->cmnd[1] & 0x02;
1300 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1301 u8 *buf = (u8 *)bh->buf;
1302
1303 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1304 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1305 return -EINVAL;
1306 }
1307 if (lba >= curlun->num_sectors) {
1308 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1309 return -EINVAL;
1310 }
1311
1312 memset(buf, 0, 8);
1313 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1314 store_cdrom_address(&buf[4], msf, lba);
1315 return 8;
1316}
1317
1318static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1319{
1320 struct fsg_lun *curlun = common->curlun;
1321 int msf = common->cmnd[1] & 0x02;
1322 int start_track = common->cmnd[6];
1323 u8 *buf = (u8 *)bh->buf;
1324
1325 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1326 start_track > 1) {
1327 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1328 return -EINVAL;
1329 }
1330
1331 memset(buf, 0, 20);
1332 buf[1] = (20-2); /* TOC data length */
1333 buf[2] = 1; /* First track number */
1334 buf[3] = 1; /* Last track number */
1335 buf[5] = 0x16; /* Data track, copying allowed */
1336 buf[6] = 0x01; /* Only track is number 1 */
1337 store_cdrom_address(&buf[8], msf, 0);
1338
1339 buf[13] = 0x16; /* Lead-out track is data */
1340 buf[14] = 0xAA; /* Lead-out track number */
1341 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1342 return 20;
1343}
1344
1345static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1346{
1347 struct fsg_lun *curlun = common->curlun;
1348 int mscmnd = common->cmnd[0];
1349 u8 *buf = (u8 *) bh->buf;
1350 u8 *buf0 = buf;
1351 int pc, page_code;
1352 int changeable_values, all_pages;
1353 int valid_page = 0;
1354 int len, limit;
1355
1356 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1357 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1358 return -EINVAL;
1359 }
1360 pc = common->cmnd[2] >> 6;
1361 page_code = common->cmnd[2] & 0x3f;
1362 if (pc == 3) {
1363 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1364 return -EINVAL;
1365 }
1366 changeable_values = (pc == 1);
1367 all_pages = (page_code == 0x3f);
1368
1369 /*
1370 * Write the mode parameter header. Fixed values are: default
1371 * medium type, no cache control (DPOFUA), and no block descriptors.
1372 * The only variable value is the WriteProtect bit. We will fill in
1373 * the mode data length later.
1374 */
1375 memset(buf, 0, 8);
1376 if (mscmnd == MODE_SENSE) {
1377 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1378 buf += 4;
1379 limit = 255;
1380 } else { /* MODE_SENSE_10 */
1381 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1382 buf += 8;
1383 limit = 65535; /* Should really be FSG_BUFLEN */
1384 }
1385
1386 /* No block descriptors */
1387
1388 /*
1389 * The mode pages, in numerical order. The only page we support
1390 * is the Caching page.
1391 */
1392 if (page_code == 0x08 || all_pages) {
1393 valid_page = 1;
1394 buf[0] = 0x08; /* Page code */
1395 buf[1] = 10; /* Page length */
1396 memset(buf+2, 0, 10); /* None of the fields are changeable */
1397
1398 if (!changeable_values) {
1399 buf[2] = 0x04; /* Write cache enable, */
1400 /* Read cache not disabled */
1401 /* No cache retention priorities */
1402 put_unaligned_be16(0xffff, &buf[4]);
1403 /* Don't disable prefetch */
1404 /* Minimum prefetch = 0 */
1405 put_unaligned_be16(0xffff, &buf[8]);
1406 /* Maximum prefetch */
1407 put_unaligned_be16(0xffff, &buf[10]);
1408 /* Maximum prefetch ceiling */
1409 }
1410 buf += 12;
1411 }
1412
1413 /*
1414 * Check that a valid page was requested and the mode data length
1415 * isn't too long.
1416 */
1417 len = buf - buf0;
1418 if (!valid_page || len > limit) {
1419 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1420 return -EINVAL;
1421 }
1422
1423 /* Store the mode data length */
1424 if (mscmnd == MODE_SENSE)
1425 buf0[0] = len - 1;
1426 else
1427 put_unaligned_be16(len - 2, buf0);
1428 return len;
1429}
1430
1431static int do_start_stop(struct fsg_common *common)
1432{
1433 struct fsg_lun *curlun = common->curlun;
1434 int loej, start;
1435
1436 if (!curlun) {
1437 return -EINVAL;
1438 } else if (!curlun->removable) {
1439 curlun->sense_data = SS_INVALID_COMMAND;
1440 return -EINVAL;
1441 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1442 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1443 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1444 return -EINVAL;
1445 }
1446
1447 loej = common->cmnd[4] & 0x02;
1448 start = common->cmnd[4] & 0x01;
1449
1450 /*
1451 * Our emulation doesn't support mounting; the medium is
1452 * available for use as soon as it is loaded.
1453 */
1454 if (start) {
1455 if (!fsg_lun_is_open(curlun)) {
1456 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1457 return -EINVAL;
1458 }
1459 return 0;
1460 }
1461
1462 /* Are we allowed to unload the media? */
1463 if (curlun->prevent_medium_removal) {
1464 LDBG(curlun, "unload attempt prevented\n");
1465 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1466 return -EINVAL;
1467 }
1468
1469 if (!loej)
1470 return 0;
1471
1472 /* Simulate an unload/eject */
1473 if (common->ops && common->ops->pre_eject) {
1474 int r = common->ops->pre_eject(common, curlun,
1475 curlun - common->luns);
1476 if (unlikely(r < 0))
1477 return r;
1478 else if (r)
1479 return 0;
1480 }
1481
1482 up_read(&common->filesem);
1483 down_write(&common->filesem);
1484 fsg_lun_close(curlun);
1485 up_write(&common->filesem);
1486 down_read(&common->filesem);
1487
1488 return common->ops && common->ops->post_eject
1489 ? min(0, common->ops->post_eject(common, curlun,
1490 curlun - common->luns))
1491 : 0;
1492}
1493
1494static int do_prevent_allow(struct fsg_common *common)
1495{
1496 struct fsg_lun *curlun = common->curlun;
1497 int prevent;
1498
1499 if (!common->curlun) {
1500 return -EINVAL;
1501 } else if (!common->curlun->removable) {
1502 common->curlun->sense_data = SS_INVALID_COMMAND;
1503 return -EINVAL;
1504 }
1505
1506 prevent = common->cmnd[4] & 0x01;
1507 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1508 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1509 return -EINVAL;
1510 }
1511
1512 if (curlun->prevent_medium_removal && !prevent)
1513 fsg_lun_fsync_sub(curlun);
1514 curlun->prevent_medium_removal = prevent;
1515 return 0;
1516}
1517
1518static int do_read_format_capacities(struct fsg_common *common,
1519 struct fsg_buffhd *bh)
1520{
1521 struct fsg_lun *curlun = common->curlun;
1522 u8 *buf = (u8 *) bh->buf;
1523
1524 buf[0] = buf[1] = buf[2] = 0;
1525 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1526 buf += 4;
1527
1528 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1529 /* Number of blocks */
1530 put_unaligned_be32(512, &buf[4]); /* Block length */
1531 buf[4] = 0x02; /* Current capacity */
1532 return 12;
1533}
1534
1535static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1536{
1537 struct fsg_lun *curlun = common->curlun;
1538
1539 /* We don't support MODE SELECT */
1540 if (curlun)
1541 curlun->sense_data = SS_INVALID_COMMAND;
1542 return -EINVAL;
1543}
1544
1545
1546/*-------------------------------------------------------------------------*/
1547
1548static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1549{
1550 int rc;
1551
1552 rc = fsg_set_halt(fsg, fsg->bulk_in);
1553 if (rc == -EAGAIN)
1554 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1555 while (rc != 0) {
1556 if (rc != -EAGAIN) {
1557 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1558 rc = 0;
1559 break;
1560 }
1561
1562 /* Wait for a short time and then try again */
1563 if (msleep_interruptible(100) != 0)
1564 return -EINTR;
1565 rc = usb_ep_set_halt(fsg->bulk_in);
1566 }
1567 return rc;
1568}
1569
1570static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1571{
1572 int rc;
1573
1574 DBG(fsg, "bulk-in set wedge\n");
1575 rc = usb_ep_set_wedge(fsg->bulk_in);
1576 if (rc == -EAGAIN)
1577 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1578 while (rc != 0) {
1579 if (rc != -EAGAIN) {
1580 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1581 rc = 0;
1582 break;
1583 }
1584
1585 /* Wait for a short time and then try again */
1586 if (msleep_interruptible(100) != 0)
1587 return -EINTR;
1588 rc = usb_ep_set_wedge(fsg->bulk_in);
1589 }
1590 return rc;
1591}
1592
1593static int throw_away_data(struct fsg_common *common)
1594{
1595 struct fsg_buffhd *bh;
1596 u32 amount;
1597 int rc;
1598
1599 for (bh = common->next_buffhd_to_drain;
1600 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1601 bh = common->next_buffhd_to_drain) {
1602
1603 /* Throw away the data in a filled buffer */
1604 if (bh->state == BUF_STATE_FULL) {
1605 smp_rmb();
1606 bh->state = BUF_STATE_EMPTY;
1607 common->next_buffhd_to_drain = bh->next;
1608
1609 /* A short packet or an error ends everything */
1610 if (bh->outreq->actual != bh->outreq->length ||
1611 bh->outreq->status != 0) {
1612 raise_exception(common,
1613 FSG_STATE_ABORT_BULK_OUT);
1614 return -EINTR;
1615 }
1616 continue;
1617 }
1618
1619 /* Try to submit another request if we need one */
1620 bh = common->next_buffhd_to_fill;
1621 if (bh->state == BUF_STATE_EMPTY
1622 && common->usb_amount_left > 0) {
1623 amount = min(common->usb_amount_left, FSG_BUFLEN);
1624
1625 /*
1626 * amount is always divisible by 512, hence by
1627 * the bulk-out maxpacket size.
1628 */
1629 bh->outreq->length = amount;
1630 bh->bulk_out_intended_length = amount;
1631 bh->outreq->short_not_ok = 1;
1632 if (!start_out_transfer(common, bh))
1633 /* Dunno what to do if common->fsg is NULL */
1634 return -EIO;
1635 common->next_buffhd_to_fill = bh->next;
1636 common->usb_amount_left -= amount;
1637 continue;
1638 }
1639
1640 /* Otherwise wait for something to happen */
1641 rc = sleep_thread(common);
1642 if (rc)
1643 return rc;
1644 }
1645 return 0;
1646}
1647
1648static int finish_reply(struct fsg_common *common)
1649{
1650 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1651 int rc = 0;
1652
1653 switch (common->data_dir) {
1654 case DATA_DIR_NONE:
1655 break; /* Nothing to send */
1656
1657 /*
1658 * If we don't know whether the host wants to read or write,
1659 * this must be CB or CBI with an unknown command. We mustn't
1660 * try to send or receive any data. So stall both bulk pipes
1661 * if we can and wait for a reset.
1662 */
1663 case DATA_DIR_UNKNOWN:
1664 if (!common->can_stall) {
1665 /* Nothing */
1666 } else if (fsg_is_set(common)) {
1667 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1668 rc = halt_bulk_in_endpoint(common->fsg);
1669 } else {
1670 /* Don't know what to do if common->fsg is NULL */
1671 rc = -EIO;
1672 }
1673 break;
1674
1675 /* All but the last buffer of data must have already been sent */
1676 case DATA_DIR_TO_HOST:
1677 if (common->data_size == 0) {
1678 /* Nothing to send */
1679
1680 /* Don't know what to do if common->fsg is NULL */
1681 } else if (!fsg_is_set(common)) {
1682 rc = -EIO;
1683
1684 /* If there's no residue, simply send the last buffer */
1685 } else if (common->residue == 0) {
1686 bh->inreq->zero = 0;
1687 if (!start_in_transfer(common, bh))
1688 return -EIO;
1689 common->next_buffhd_to_fill = bh->next;
1690
1691 /*
1692 * For Bulk-only, mark the end of the data with a short
1693 * packet. If we are allowed to stall, halt the bulk-in
1694 * endpoint. (Note: This violates the Bulk-Only Transport
1695 * specification, which requires us to pad the data if we
1696 * don't halt the endpoint. Presumably nobody will mind.)
1697 */
1698 } else {
1699 bh->inreq->zero = 1;
1700 if (!start_in_transfer(common, bh))
1701 rc = -EIO;
1702 common->next_buffhd_to_fill = bh->next;
1703 if (common->can_stall)
1704 rc = halt_bulk_in_endpoint(common->fsg);
1705 }
1706 break;
1707
1708 /*
1709 * We have processed all we want from the data the host has sent.
1710 * There may still be outstanding bulk-out requests.
1711 */
1712 case DATA_DIR_FROM_HOST:
1713 if (common->residue == 0) {
1714 /* Nothing to receive */
1715
1716 /* Did the host stop sending unexpectedly early? */
1717 } else if (common->short_packet_received) {
1718 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1719 rc = -EINTR;
1720
1721 /*
1722 * We haven't processed all the incoming data. Even though
1723 * we may be allowed to stall, doing so would cause a race.
1724 * The controller may already have ACK'ed all the remaining
1725 * bulk-out packets, in which case the host wouldn't see a
1726 * STALL. Not realizing the endpoint was halted, it wouldn't
1727 * clear the halt -- leading to problems later on.
1728 */
1729#if 0
1730 } else if (common->can_stall) {
1731 if (fsg_is_set(common))
1732 fsg_set_halt(common->fsg,
1733 common->fsg->bulk_out);
1734 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1735 rc = -EINTR;
1736#endif
1737
1738 /*
1739 * We can't stall. Read in the excess data and throw it
1740 * all away.
1741 */
1742 } else {
1743 rc = throw_away_data(common);
1744 }
1745 break;
1746 }
1747 return rc;
1748}
1749
1750static int send_status(struct fsg_common *common)
1751{
1752 struct fsg_lun *curlun = common->curlun;
1753 struct fsg_buffhd *bh;
1754 struct bulk_cs_wrap *csw;
1755 int rc;
1756 u8 status = USB_STATUS_PASS;
1757 u32 sd, sdinfo = 0;
1758
1759 /* Wait for the next buffer to become available */
1760 bh = common->next_buffhd_to_fill;
1761 while (bh->state != BUF_STATE_EMPTY) {
1762 rc = sleep_thread(common);
1763 if (rc)
1764 return rc;
1765 }
1766
1767 if (curlun) {
1768 sd = curlun->sense_data;
1769 sdinfo = curlun->sense_data_info;
1770 } else if (common->bad_lun_okay)
1771 sd = SS_NO_SENSE;
1772 else
1773 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1774
1775 if (common->phase_error) {
1776 DBG(common, "sending phase-error status\n");
1777 status = USB_STATUS_PHASE_ERROR;
1778 sd = SS_INVALID_COMMAND;
1779 } else if (sd != SS_NO_SENSE) {
1780 DBG(common, "sending command-failure status\n");
1781 status = USB_STATUS_FAIL;
1782 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1783 " info x%x\n",
1784 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1785 }
1786
1787 /* Store and send the Bulk-only CSW */
1788 csw = (void *)bh->buf;
1789
1790 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1791 csw->Tag = common->tag;
1792 csw->Residue = cpu_to_le32(common->residue);
1793 csw->Status = status;
1794
1795 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1796 bh->inreq->zero = 0;
1797 if (!start_in_transfer(common, bh))
1798 /* Don't know what to do if common->fsg is NULL */
1799 return -EIO;
1800
1801 common->next_buffhd_to_fill = bh->next;
1802 return 0;
1803}
1804
1805
1806/*-------------------------------------------------------------------------*/
1807
1808/*
1809 * Check whether the command is properly formed and whether its data size
1810 * and direction agree with the values we already have.
1811 */
1812static int check_command(struct fsg_common *common, int cmnd_size,
1813 enum data_direction data_dir, unsigned int mask,
1814 int needs_medium, const char *name)
1815{
1816 int i;
1817 int lun = common->cmnd[1] >> 5;
1818 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1819 char hdlen[20];
1820 struct fsg_lun *curlun;
1821
1822 hdlen[0] = 0;
1823 if (common->data_dir != DATA_DIR_UNKNOWN)
1824 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1825 common->data_size);
1826 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1827 name, cmnd_size, dirletter[(int) data_dir],
1828 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1829
1830 /*
1831 * We can't reply at all until we know the correct data direction
1832 * and size.
1833 */
1834 if (common->data_size_from_cmnd == 0)
1835 data_dir = DATA_DIR_NONE;
1836 if (common->data_size < common->data_size_from_cmnd) {
1837 /*
1838 * Host data size < Device data size is a phase error.
1839 * Carry out the command, but only transfer as much as
1840 * we are allowed.
1841 */
1842 common->data_size_from_cmnd = common->data_size;
1843 common->phase_error = 1;
1844 }
1845 common->residue = common->data_size;
1846 common->usb_amount_left = common->data_size;
1847
1848 /* Conflicting data directions is a phase error */
1849 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1850 common->phase_error = 1;
1851 return -EINVAL;
1852 }
1853
1854 /* Verify the length of the command itself */
1855 if (cmnd_size != common->cmnd_size) {
1856
1857 /*
1858 * Special case workaround: There are plenty of buggy SCSI
1859 * implementations. Many have issues with cbw->Length
1860 * field passing a wrong command size. For those cases we
1861 * always try to work around the problem by using the length
1862 * sent by the host side provided it is at least as large
1863 * as the correct command length.
1864 * Examples of such cases would be MS-Windows, which issues
1865 * REQUEST SENSE with cbw->Length == 12 where it should
1866 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1867 * REQUEST SENSE with cbw->Length == 10 where it should
1868 * be 6 as well.
1869 */
1870 if (cmnd_size <= common->cmnd_size) {
1871 DBG(common, "%s is buggy! Expected length %d "
1872 "but we got %d\n", name,
1873 cmnd_size, common->cmnd_size);
1874 cmnd_size = common->cmnd_size;
1875 } else {
1876 common->phase_error = 1;
1877 return -EINVAL;
1878 }
1879 }
1880
1881 /* Check that the LUN values are consistent */
1882 if (common->lun != lun)
1883 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1884 common->lun, lun);
1885
1886 /* Check the LUN */
1887 if (common->lun < common->nluns) {
1888 curlun = &common->luns[common->lun];
1889 common->curlun = curlun;
1890 if (common->cmnd[0] != REQUEST_SENSE) {
1891 curlun->sense_data = SS_NO_SENSE;
1892 curlun->sense_data_info = 0;
1893 curlun->info_valid = 0;
1894 }
1895 } else {
1896 common->curlun = NULL;
1897 curlun = NULL;
1898 common->bad_lun_okay = 0;
1899
1900 /*
1901 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1902 * to use unsupported LUNs; all others may not.
1903 */
1904 if (common->cmnd[0] != INQUIRY &&
1905 common->cmnd[0] != REQUEST_SENSE) {
1906 DBG(common, "unsupported LUN %d\n", common->lun);
1907 return -EINVAL;
1908 }
1909 }
1910
1911 /*
1912 * If a unit attention condition exists, only INQUIRY and
1913 * REQUEST SENSE commands are allowed; anything else must fail.
1914 */
1915 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1916 common->cmnd[0] != INQUIRY &&
1917 common->cmnd[0] != REQUEST_SENSE) {
1918 curlun->sense_data = curlun->unit_attention_data;
1919 curlun->unit_attention_data = SS_NO_SENSE;
1920 return -EINVAL;
1921 }
1922
1923 /* Check that only command bytes listed in the mask are non-zero */
1924 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1925 for (i = 1; i < cmnd_size; ++i) {
1926 if (common->cmnd[i] && !(mask & (1 << i))) {
1927 if (curlun)
1928 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1929 return -EINVAL;
1930 }
1931 }
1932
1933 /* If the medium isn't mounted and the command needs to access
1934 * it, return an error. */
1935 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1936 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1937 return -EINVAL;
1938 }
1939
1940 return 0;
1941}
1942
1943static int do_scsi_command(struct fsg_common *common)
1944{
1945 struct fsg_buffhd *bh;
1946 int rc;
1947 int reply = -EINVAL;
1948 int i;
1949 static char unknown[16];
1950
1951 dump_cdb(common);
1952
1953 /* Wait for the next buffer to become available for data or status */
1954 bh = common->next_buffhd_to_fill;
1955 common->next_buffhd_to_drain = bh;
1956 while (bh->state != BUF_STATE_EMPTY) {
1957 rc = sleep_thread(common);
1958 if (rc)
1959 return rc;
1960 }
1961 common->phase_error = 0;
1962 common->short_packet_received = 0;
1963
1964 down_read(&common->filesem); /* We're using the backing file */
1965 switch (common->cmnd[0]) {
1966
1967 case INQUIRY:
1968 common->data_size_from_cmnd = common->cmnd[4];
1969 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1970 (1<<4), 0,
1971 "INQUIRY");
1972 if (reply == 0)
1973 reply = do_inquiry(common, bh);
1974 break;
1975
1976 case MODE_SELECT:
1977 common->data_size_from_cmnd = common->cmnd[4];
1978 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1979 (1<<1) | (1<<4), 0,
1980 "MODE SELECT(6)");
1981 if (reply == 0)
1982 reply = do_mode_select(common, bh);
1983 break;
1984
1985 case MODE_SELECT_10:
1986 common->data_size_from_cmnd =
1987 get_unaligned_be16(&common->cmnd[7]);
1988 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1989 (1<<1) | (3<<7), 0,
1990 "MODE SELECT(10)");
1991 if (reply == 0)
1992 reply = do_mode_select(common, bh);
1993 break;
1994
1995 case MODE_SENSE:
1996 common->data_size_from_cmnd = common->cmnd[4];
1997 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1998 (1<<1) | (1<<2) | (1<<4), 0,
1999 "MODE SENSE(6)");
2000 if (reply == 0)
2001 reply = do_mode_sense(common, bh);
2002 break;
2003
2004 case MODE_SENSE_10:
2005 common->data_size_from_cmnd =
2006 get_unaligned_be16(&common->cmnd[7]);
2007 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2008 (1<<1) | (1<<2) | (3<<7), 0,
2009 "MODE SENSE(10)");
2010 if (reply == 0)
2011 reply = do_mode_sense(common, bh);
2012 break;
2013
2014 case ALLOW_MEDIUM_REMOVAL:
2015 common->data_size_from_cmnd = 0;
2016 reply = check_command(common, 6, DATA_DIR_NONE,
2017 (1<<4), 0,
2018 "PREVENT-ALLOW MEDIUM REMOVAL");
2019 if (reply == 0)
2020 reply = do_prevent_allow(common);
2021 break;
2022
2023 case READ_6:
2024 i = common->cmnd[4];
2025 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2026 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2027 (7<<1) | (1<<4), 1,
2028 "READ(6)");
2029 if (reply == 0)
2030 reply = do_read(common);
2031 break;
2032
2033 case READ_10:
2034 common->data_size_from_cmnd =
2035 get_unaligned_be16(&common->cmnd[7]) << 9;
2036 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2037 (1<<1) | (0xf<<2) | (3<<7), 1,
2038 "READ(10)");
2039 if (reply == 0)
2040 reply = do_read(common);
2041 break;
2042
2043 case READ_12:
2044 common->data_size_from_cmnd =
2045 get_unaligned_be32(&common->cmnd[6]) << 9;
2046 reply = check_command(common, 12, DATA_DIR_TO_HOST,
2047 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2048 "READ(12)");
2049 if (reply == 0)
2050 reply = do_read(common);
2051 break;
2052
2053 case READ_CAPACITY:
2054 common->data_size_from_cmnd = 8;
2055 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2056 (0xf<<2) | (1<<8), 1,
2057 "READ CAPACITY");
2058 if (reply == 0)
2059 reply = do_read_capacity(common, bh);
2060 break;
2061
2062 case READ_HEADER:
2063 if (!common->curlun || !common->curlun->cdrom)
2064 goto unknown_cmnd;
2065 common->data_size_from_cmnd =
2066 get_unaligned_be16(&common->cmnd[7]);
2067 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2068 (3<<7) | (0x1f<<1), 1,
2069 "READ HEADER");
2070 if (reply == 0)
2071 reply = do_read_header(common, bh);
2072 break;
2073
2074 case READ_TOC:
2075 if (!common->curlun || !common->curlun->cdrom)
2076 goto unknown_cmnd;
2077 common->data_size_from_cmnd =
2078 get_unaligned_be16(&common->cmnd[7]);
2079 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2080 (7<<6) | (1<<1), 1,
2081 "READ TOC");
2082 if (reply == 0)
2083 reply = do_read_toc(common, bh);
2084 break;
2085
2086 case READ_FORMAT_CAPACITIES:
2087 common->data_size_from_cmnd =
2088 get_unaligned_be16(&common->cmnd[7]);
2089 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2090 (3<<7), 1,
2091 "READ FORMAT CAPACITIES");
2092 if (reply == 0)
2093 reply = do_read_format_capacities(common, bh);
2094 break;
2095
2096 case REQUEST_SENSE:
2097 common->data_size_from_cmnd = common->cmnd[4];
2098 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2099 (1<<4), 0,
2100 "REQUEST SENSE");
2101 if (reply == 0)
2102 reply = do_request_sense(common, bh);
2103 break;
2104
2105 case START_STOP:
2106 common->data_size_from_cmnd = 0;
2107 reply = check_command(common, 6, DATA_DIR_NONE,
2108 (1<<1) | (1<<4), 0,
2109 "START-STOP UNIT");
2110 if (reply == 0)
2111 reply = do_start_stop(common);
2112 break;
2113
2114 case SYNCHRONIZE_CACHE:
2115 common->data_size_from_cmnd = 0;
2116 reply = check_command(common, 10, DATA_DIR_NONE,
2117 (0xf<<2) | (3<<7), 1,
2118 "SYNCHRONIZE CACHE");
2119 if (reply == 0)
2120 reply = do_synchronize_cache(common);
2121 break;
2122
2123 case TEST_UNIT_READY:
2124 common->data_size_from_cmnd = 0;
2125 reply = check_command(common, 6, DATA_DIR_NONE,
2126 0, 1,
2127 "TEST UNIT READY");
2128 break;
2129
2130 /*
2131 * Although optional, this command is used by MS-Windows. We
2132 * support a minimal version: BytChk must be 0.
2133 */
2134 case VERIFY:
2135 common->data_size_from_cmnd = 0;
2136 reply = check_command(common, 10, DATA_DIR_NONE,
2137 (1<<1) | (0xf<<2) | (3<<7), 1,
2138 "VERIFY");
2139 if (reply == 0)
2140 reply = do_verify(common);
2141 break;
2142
2143 case WRITE_6:
2144 i = common->cmnd[4];
2145 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
2146 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
2147 (7<<1) | (1<<4), 1,
2148 "WRITE(6)");
2149 if (reply == 0)
2150 reply = do_write(common);
2151 break;
2152
2153 case WRITE_10:
2154 common->data_size_from_cmnd =
2155 get_unaligned_be16(&common->cmnd[7]) << 9;
2156 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2157 (1<<1) | (0xf<<2) | (3<<7), 1,
2158 "WRITE(10)");
2159 if (reply == 0)
2160 reply = do_write(common);
2161 break;
2162
2163 case WRITE_12:
2164 common->data_size_from_cmnd =
2165 get_unaligned_be32(&common->cmnd[6]) << 9;
2166 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2167 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2168 "WRITE(12)");
2169 if (reply == 0)
2170 reply = do_write(common);
2171 break;
2172
2173 /*
2174 * Some mandatory commands that we recognize but don't implement.
2175 * They don't mean much in this setting. It's left as an exercise
2176 * for anyone interested to implement RESERVE and RELEASE in terms
2177 * of Posix locks.
2178 */
2179 case FORMAT_UNIT:
2180 case RELEASE:
2181 case RESERVE:
2182 case SEND_DIAGNOSTIC:
2183 /* Fall through */
2184
2185 default:
2186unknown_cmnd:
2187 common->data_size_from_cmnd = 0;
2188 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2189 reply = check_command(common, common->cmnd_size,
2190 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2191 if (reply == 0) {
2192 common->curlun->sense_data = SS_INVALID_COMMAND;
2193 reply = -EINVAL;
2194 }
2195 break;
2196 }
2197 up_read(&common->filesem);
2198
2199 if (reply == -EINTR || signal_pending(current))
2200 return -EINTR;
2201
2202 /* Set up the single reply buffer for finish_reply() */
2203 if (reply == -EINVAL)
2204 reply = 0; /* Error reply length */
2205 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2206 reply = min((u32)reply, common->data_size_from_cmnd);
2207 bh->inreq->length = reply;
2208 bh->state = BUF_STATE_FULL;
2209 common->residue -= reply;
2210 } /* Otherwise it's already set */
2211
2212 return 0;
2213}
2214
2215
2216/*-------------------------------------------------------------------------*/
2217
2218static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2219{
2220 struct usb_request *req = bh->outreq;
2221 struct fsg_bulk_cb_wrap *cbw = req->buf;
2222 struct fsg_common *common = fsg->common;
2223
2224 /* Was this a real packet? Should it be ignored? */
2225 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2226 return -EINVAL;
2227
2228 /* Is the CBW valid? */
2229 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2230 cbw->Signature != cpu_to_le32(
2231 USB_BULK_CB_SIG)) {
2232 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2233 req->actual,
2234 le32_to_cpu(cbw->Signature));
2235
2236 /*
2237 * The Bulk-only spec says we MUST stall the IN endpoint
2238 * (6.6.1), so it's unavoidable. It also says we must
2239 * retain this state until the next reset, but there's
2240 * no way to tell the controller driver it should ignore
2241 * Clear-Feature(HALT) requests.
2242 *
2243 * We aren't required to halt the OUT endpoint; instead
2244 * we can simply accept and discard any data received
2245 * until the next reset.
2246 */
2247 wedge_bulk_in_endpoint(fsg);
2248 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2249 return -EINVAL;
2250 }
2251
2252 /* Is the CBW meaningful? */
2253 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2254 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2255 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2256 "cmdlen %u\n",
2257 cbw->Lun, cbw->Flags, cbw->Length);
2258
2259 /*
2260 * We can do anything we want here, so let's stall the
2261 * bulk pipes if we are allowed to.
2262 */
2263 if (common->can_stall) {
2264 fsg_set_halt(fsg, fsg->bulk_out);
2265 halt_bulk_in_endpoint(fsg);
2266 }
2267 return -EINVAL;
2268 }
2269
2270 /* Save the command for later */
2271 common->cmnd_size = cbw->Length;
2272 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2273 if (cbw->Flags & USB_BULK_IN_FLAG)
2274 common->data_dir = DATA_DIR_TO_HOST;
2275 else
2276 common->data_dir = DATA_DIR_FROM_HOST;
2277 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2278 if (common->data_size == 0)
2279 common->data_dir = DATA_DIR_NONE;
2280 common->lun = cbw->Lun;
2281 common->tag = cbw->Tag;
2282 return 0;
2283}
2284
2285static int get_next_command(struct fsg_common *common)
2286{
2287 struct fsg_buffhd *bh;
2288 int rc = 0;
2289
2290 /* Wait for the next buffer to become available */
2291 bh = common->next_buffhd_to_fill;
2292 while (bh->state != BUF_STATE_EMPTY) {
2293 rc = sleep_thread(common);
2294 if (rc)
2295 return rc;
2296 }
2297
2298 /* Queue a request to read a Bulk-only CBW */
2299 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2300 bh->outreq->short_not_ok = 1;
2301 if (!start_out_transfer(common, bh))
2302 /* Don't know what to do if common->fsg is NULL */
2303 return -EIO;
2304
2305 /*
2306 * We will drain the buffer in software, which means we
2307 * can reuse it for the next filling. No need to advance
2308 * next_buffhd_to_fill.
2309 */
2310
2311 /* Wait for the CBW to arrive */
2312 while (bh->state != BUF_STATE_FULL) {
2313 rc = sleep_thread(common);
2314 if (rc)
2315 return rc;
2316 }
2317 smp_rmb();
2318 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2319 bh->state = BUF_STATE_EMPTY;
2320
2321 return rc;
2322}
2323
2324
2325/*-------------------------------------------------------------------------*/
2326
2327static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2328 struct usb_request **preq)
2329{
2330 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2331 if (*preq)
2332 return 0;
2333 ERROR(common, "can't allocate request for %s\n", ep->name);
2334 return -ENOMEM;
2335}
2336
2337/* Reset interface setting and re-init endpoint state (toggle etc). */
2338static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2339{
2340 struct fsg_dev *fsg;
2341 int i, rc = 0;
2342
2343 if (common->running)
2344 DBG(common, "reset interface\n");
2345
2346reset:
2347 /* Deallocate the requests */
2348 if (common->fsg) {
2349 fsg = common->fsg;
2350
2351 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2352 struct fsg_buffhd *bh = &common->buffhds[i];
2353
2354 if (bh->inreq) {
2355 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2356 bh->inreq = NULL;
2357 }
2358 if (bh->outreq) {
2359 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2360 bh->outreq = NULL;
2361 }
2362 }
2363
2364 /* Disable the endpoints */
2365 if (fsg->bulk_in_enabled) {
2366 usb_ep_disable(fsg->bulk_in);
2367 fsg->bulk_in_enabled = 0;
2368 }
2369 if (fsg->bulk_out_enabled) {
2370 usb_ep_disable(fsg->bulk_out);
2371 fsg->bulk_out_enabled = 0;
2372 }
2373
2374 common->fsg = NULL;
2375 wake_up(&common->fsg_wait);
2376 }
2377
2378 common->running = 0;
2379 if (!new_fsg || rc)
2380 return rc;
2381
2382 common->fsg = new_fsg;
2383 fsg = common->fsg;
2384
2385 /* Enable the endpoints */
2386 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2387 if (rc)
2388 goto reset;
2389 rc = usb_ep_enable(fsg->bulk_in);
2390 if (rc)
2391 goto reset;
2392 fsg->bulk_in->driver_data = common;
2393 fsg->bulk_in_enabled = 1;
2394
2395 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2396 fsg->bulk_out);
2397 if (rc)
2398 goto reset;
2399 rc = usb_ep_enable(fsg->bulk_out);
2400 if (rc)
2401 goto reset;
2402 fsg->bulk_out->driver_data = common;
2403 fsg->bulk_out_enabled = 1;
2404 common->bulk_out_maxpacket =
2405 le16_to_cpu(fsg->bulk_out->desc->wMaxPacketSize);
2406 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2407
2408 /* Allocate the requests */
2409 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2410 struct fsg_buffhd *bh = &common->buffhds[i];
2411
2412 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2413 if (rc)
2414 goto reset;
2415 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2416 if (rc)
2417 goto reset;
2418 bh->inreq->buf = bh->outreq->buf = bh->buf;
2419 bh->inreq->context = bh->outreq->context = bh;
2420 bh->inreq->complete = bulk_in_complete;
2421 bh->outreq->complete = bulk_out_complete;
2422 }
2423
2424 common->running = 1;
2425 for (i = 0; i < common->nluns; ++i)
2426 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2427 return rc;
2428}
2429
2430
2431/****************************** ALT CONFIGS ******************************/
2432
2433static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2434{
2435 struct fsg_dev *fsg = fsg_from_func(f);
2436 fsg->common->new_fsg = fsg;
2437 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2438 return USB_GADGET_DELAYED_STATUS;
2439}
2440
2441static void fsg_disable(struct usb_function *f)
2442{
2443 struct fsg_dev *fsg = fsg_from_func(f);
2444 fsg->common->new_fsg = NULL;
2445 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2446}
2447
2448
2449/*-------------------------------------------------------------------------*/
2450
2451static void handle_exception(struct fsg_common *common)
2452{
2453 siginfo_t info;
2454 int i;
2455 struct fsg_buffhd *bh;
2456 enum fsg_state old_state;
2457 struct fsg_lun *curlun;
2458 unsigned int exception_req_tag;
2459
2460 /*
2461 * Clear the existing signals. Anything but SIGUSR1 is converted
2462 * into a high-priority EXIT exception.
2463 */
2464 for (;;) {
2465 int sig =
2466 dequeue_signal_lock(current, ¤t->blocked, &info);
2467 if (!sig)
2468 break;
2469 if (sig != SIGUSR1) {
2470 if (common->state < FSG_STATE_EXIT)
2471 DBG(common, "Main thread exiting on signal\n");
2472 raise_exception(common, FSG_STATE_EXIT);
2473 }
2474 }
2475
2476 /* Cancel all the pending transfers */
2477 if (likely(common->fsg)) {
2478 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2479 bh = &common->buffhds[i];
2480 if (bh->inreq_busy)
2481 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2482 if (bh->outreq_busy)
2483 usb_ep_dequeue(common->fsg->bulk_out,
2484 bh->outreq);
2485 }
2486
2487 /* Wait until everything is idle */
2488 for (;;) {
2489 int num_active = 0;
2490 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2491 bh = &common->buffhds[i];
2492 num_active += bh->inreq_busy + bh->outreq_busy;
2493 }
2494 if (num_active == 0)
2495 break;
2496 if (sleep_thread(common))
2497 return;
2498 }
2499
2500 /* Clear out the controller's fifos */
2501 if (common->fsg->bulk_in_enabled)
2502 usb_ep_fifo_flush(common->fsg->bulk_in);
2503 if (common->fsg->bulk_out_enabled)
2504 usb_ep_fifo_flush(common->fsg->bulk_out);
2505 }
2506
2507 /*
2508 * Reset the I/O buffer states and pointers, the SCSI
2509 * state, and the exception. Then invoke the handler.
2510 */
2511 spin_lock_irq(&common->lock);
2512
2513 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2514 bh = &common->buffhds[i];
2515 bh->state = BUF_STATE_EMPTY;
2516 }
2517 common->next_buffhd_to_fill = &common->buffhds[0];
2518 common->next_buffhd_to_drain = &common->buffhds[0];
2519 exception_req_tag = common->exception_req_tag;
2520 old_state = common->state;
2521
2522 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2523 common->state = FSG_STATE_STATUS_PHASE;
2524 else {
2525 for (i = 0; i < common->nluns; ++i) {
2526 curlun = &common->luns[i];
2527 curlun->prevent_medium_removal = 0;
2528 curlun->sense_data = SS_NO_SENSE;
2529 curlun->unit_attention_data = SS_NO_SENSE;
2530 curlun->sense_data_info = 0;
2531 curlun->info_valid = 0;
2532 }
2533 common->state = FSG_STATE_IDLE;
2534 }
2535 spin_unlock_irq(&common->lock);
2536
2537 /* Carry out any extra actions required for the exception */
2538 switch (old_state) {
2539 case FSG_STATE_ABORT_BULK_OUT:
2540 send_status(common);
2541 spin_lock_irq(&common->lock);
2542 if (common->state == FSG_STATE_STATUS_PHASE)
2543 common->state = FSG_STATE_IDLE;
2544 spin_unlock_irq(&common->lock);
2545 break;
2546
2547 case FSG_STATE_RESET:
2548 /*
2549 * In case we were forced against our will to halt a
2550 * bulk endpoint, clear the halt now. (The SuperH UDC
2551 * requires this.)
2552 */
2553 if (!fsg_is_set(common))
2554 break;
2555 if (test_and_clear_bit(IGNORE_BULK_OUT,
2556 &common->fsg->atomic_bitflags))
2557 usb_ep_clear_halt(common->fsg->bulk_in);
2558
2559 if (common->ep0_req_tag == exception_req_tag)
2560 ep0_queue(common); /* Complete the status stage */
2561
2562 /*
2563 * Technically this should go here, but it would only be
2564 * a waste of time. Ditto for the INTERFACE_CHANGE and
2565 * CONFIG_CHANGE cases.
2566 */
2567 /* for (i = 0; i < common->nluns; ++i) */
2568 /* common->luns[i].unit_attention_data = */
2569 /* SS_RESET_OCCURRED; */
2570 break;
2571
2572 case FSG_STATE_CONFIG_CHANGE:
2573 do_set_interface(common, common->new_fsg);
2574 if (common->new_fsg)
2575 usb_composite_setup_continue(common->cdev);
2576 break;
2577
2578 case FSG_STATE_EXIT:
2579 case FSG_STATE_TERMINATED:
2580 do_set_interface(common, NULL); /* Free resources */
2581 spin_lock_irq(&common->lock);
2582 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2583 spin_unlock_irq(&common->lock);
2584 break;
2585
2586 case FSG_STATE_INTERFACE_CHANGE:
2587 case FSG_STATE_DISCONNECT:
2588 case FSG_STATE_COMMAND_PHASE:
2589 case FSG_STATE_DATA_PHASE:
2590 case FSG_STATE_STATUS_PHASE:
2591 case FSG_STATE_IDLE:
2592 break;
2593 }
2594}
2595
2596
2597/*-------------------------------------------------------------------------*/
2598
2599static int fsg_main_thread(void *common_)
2600{
2601 struct fsg_common *common = common_;
2602
2603 /*
2604 * Allow the thread to be killed by a signal, but set the signal mask
2605 * to block everything but INT, TERM, KILL, and USR1.
2606 */
2607 allow_signal(SIGINT);
2608 allow_signal(SIGTERM);
2609 allow_signal(SIGKILL);
2610 allow_signal(SIGUSR1);
2611
2612 /* Allow the thread to be frozen */
2613 set_freezable();
2614
2615 /*
2616 * Arrange for userspace references to be interpreted as kernel
2617 * pointers. That way we can pass a kernel pointer to a routine
2618 * that expects a __user pointer and it will work okay.
2619 */
2620 set_fs(get_ds());
2621
2622 /* The main loop */
2623 while (common->state != FSG_STATE_TERMINATED) {
2624 if (exception_in_progress(common) || signal_pending(current)) {
2625 handle_exception(common);
2626 continue;
2627 }
2628
2629 if (!common->running) {
2630 sleep_thread(common);
2631 continue;
2632 }
2633
2634 if (get_next_command(common))
2635 continue;
2636
2637 spin_lock_irq(&common->lock);
2638 if (!exception_in_progress(common))
2639 common->state = FSG_STATE_DATA_PHASE;
2640 spin_unlock_irq(&common->lock);
2641
2642 if (do_scsi_command(common) || finish_reply(common))
2643 continue;
2644
2645 spin_lock_irq(&common->lock);
2646 if (!exception_in_progress(common))
2647 common->state = FSG_STATE_STATUS_PHASE;
2648 spin_unlock_irq(&common->lock);
2649
2650 if (send_status(common))
2651 continue;
2652
2653 spin_lock_irq(&common->lock);
2654 if (!exception_in_progress(common))
2655 common->state = FSG_STATE_IDLE;
2656 spin_unlock_irq(&common->lock);
2657 }
2658
2659 spin_lock_irq(&common->lock);
2660 common->thread_task = NULL;
2661 spin_unlock_irq(&common->lock);
2662
2663 if (!common->ops || !common->ops->thread_exits
2664 || common->ops->thread_exits(common) < 0) {
2665 struct fsg_lun *curlun = common->luns;
2666 unsigned i = common->nluns;
2667
2668 down_write(&common->filesem);
2669 for (; i--; ++curlun) {
2670 if (!fsg_lun_is_open(curlun))
2671 continue;
2672
2673 fsg_lun_close(curlun);
2674 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2675 }
2676 up_write(&common->filesem);
2677 }
2678
2679 /* Let fsg_unbind() know the thread has exited */
2680 complete_and_exit(&common->thread_notifier, 0);
2681}
2682
2683
2684/*************************** DEVICE ATTRIBUTES ***************************/
2685
2686/* Write permission is checked per LUN in store_*() functions. */
2687static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2688static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2689static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2690
2691
2692/****************************** FSG COMMON ******************************/
2693
2694static void fsg_common_release(struct kref *ref);
2695
2696static void fsg_lun_release(struct device *dev)
2697{
2698 /* Nothing needs to be done */
2699}
2700
2701static inline void fsg_common_get(struct fsg_common *common)
2702{
2703 kref_get(&common->ref);
2704}
2705
2706static inline void fsg_common_put(struct fsg_common *common)
2707{
2708 kref_put(&common->ref, fsg_common_release);
2709}
2710
2711static struct fsg_common *fsg_common_init(struct fsg_common *common,
2712 struct usb_composite_dev *cdev,
2713 struct fsg_config *cfg)
2714{
2715 struct usb_gadget *gadget = cdev->gadget;
2716 struct fsg_buffhd *bh;
2717 struct fsg_lun *curlun;
2718 struct fsg_lun_config *lcfg;
2719 int nluns, i, rc;
2720 char *pathbuf;
2721
2722 /* Find out how many LUNs there should be */
2723 nluns = cfg->nluns;
2724 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2725 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2726 return ERR_PTR(-EINVAL);
2727 }
2728
2729 /* Allocate? */
2730 if (!common) {
2731 common = kzalloc(sizeof *common, GFP_KERNEL);
2732 if (!common)
2733 return ERR_PTR(-ENOMEM);
2734 common->free_storage_on_release = 1;
2735 } else {
2736 memset(common, 0, sizeof *common);
2737 common->free_storage_on_release = 0;
2738 }
2739
2740 common->ops = cfg->ops;
2741 common->private_data = cfg->private_data;
2742
2743 common->gadget = gadget;
2744 common->ep0 = gadget->ep0;
2745 common->ep0req = cdev->req;
2746 common->cdev = cdev;
2747
2748 /* Maybe allocate device-global string IDs, and patch descriptors */
2749 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2750 rc = usb_string_id(cdev);
2751 if (unlikely(rc < 0))
2752 goto error_release;
2753 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2754 fsg_intf_desc.iInterface = rc;
2755 }
2756
2757 /*
2758 * Create the LUNs, open their backing files, and register the
2759 * LUN devices in sysfs.
2760 */
2761 curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
2762 if (unlikely(!curlun)) {
2763 rc = -ENOMEM;
2764 goto error_release;
2765 }
2766 common->luns = curlun;
2767
2768 init_rwsem(&common->filesem);
2769
2770 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2771 curlun->cdrom = !!lcfg->cdrom;
2772 curlun->ro = lcfg->cdrom || lcfg->ro;
2773 curlun->initially_ro = curlun->ro;
2774 curlun->removable = lcfg->removable;
2775 curlun->dev.release = fsg_lun_release;
2776 curlun->dev.parent = &gadget->dev;
2777 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2778 dev_set_drvdata(&curlun->dev, &common->filesem);
2779 dev_set_name(&curlun->dev,
2780 cfg->lun_name_format
2781 ? cfg->lun_name_format
2782 : "lun%d",
2783 i);
2784
2785 rc = device_register(&curlun->dev);
2786 if (rc) {
2787 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2788 common->nluns = i;
2789 put_device(&curlun->dev);
2790 goto error_release;
2791 }
2792
2793 rc = device_create_file(&curlun->dev, &dev_attr_ro);
2794 if (rc)
2795 goto error_luns;
2796 rc = device_create_file(&curlun->dev, &dev_attr_file);
2797 if (rc)
2798 goto error_luns;
2799 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2800 if (rc)
2801 goto error_luns;
2802
2803 if (lcfg->filename) {
2804 rc = fsg_lun_open(curlun, lcfg->filename);
2805 if (rc)
2806 goto error_luns;
2807 } else if (!curlun->removable) {
2808 ERROR(common, "no file given for LUN%d\n", i);
2809 rc = -EINVAL;
2810 goto error_luns;
2811 }
2812 }
2813 common->nluns = nluns;
2814
2815 /* Data buffers cyclic list */
2816 bh = common->buffhds;
2817 i = FSG_NUM_BUFFERS;
2818 goto buffhds_first_it;
2819 do {
2820 bh->next = bh + 1;
2821 ++bh;
2822buffhds_first_it:
2823 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2824 if (unlikely(!bh->buf)) {
2825 rc = -ENOMEM;
2826 goto error_release;
2827 }
2828 } while (--i);
2829 bh->next = common->buffhds;
2830
2831 /* Prepare inquiryString */
2832 if (cfg->release != 0xffff) {
2833 i = cfg->release;
2834 } else {
2835 i = usb_gadget_controller_number(gadget);
2836 if (i >= 0) {
2837 i = 0x0300 + i;
2838 } else {
2839 WARNING(common, "controller '%s' not recognized\n",
2840 gadget->name);
2841 i = 0x0399;
2842 }
2843 }
2844 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2845 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2846 /* Assume product name dependent on the first LUN */
2847 cfg->product_name ?: (common->luns->cdrom
2848 ? "File-Stor Gadget"
2849 : "File-CD Gadget"),
2850 i);
2851
2852 /*
2853 * Some peripheral controllers are known not to be able to
2854 * halt bulk endpoints correctly. If one of them is present,
2855 * disable stalls.
2856 */
2857 common->can_stall = cfg->can_stall &&
2858 !(gadget_is_at91(common->gadget));
2859
2860 spin_lock_init(&common->lock);
2861 kref_init(&common->ref);
2862
2863 /* Tell the thread to start working */
2864 common->thread_task =
2865 kthread_create(fsg_main_thread, common,
2866 cfg->thread_name ?: "file-storage");
2867 if (IS_ERR(common->thread_task)) {
2868 rc = PTR_ERR(common->thread_task);
2869 goto error_release;
2870 }
2871 init_completion(&common->thread_notifier);
2872 init_waitqueue_head(&common->fsg_wait);
2873
2874 /* Information */
2875 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2876 INFO(common, "Number of LUNs=%d\n", common->nluns);
2877
2878 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2879 for (i = 0, nluns = common->nluns, curlun = common->luns;
2880 i < nluns;
2881 ++curlun, ++i) {
2882 char *p = "(no medium)";
2883 if (fsg_lun_is_open(curlun)) {
2884 p = "(error)";
2885 if (pathbuf) {
2886 p = d_path(&curlun->filp->f_path,
2887 pathbuf, PATH_MAX);
2888 if (IS_ERR(p))
2889 p = "(error)";
2890 }
2891 }
2892 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2893 curlun->removable ? "removable " : "",
2894 curlun->ro ? "read only " : "",
2895 curlun->cdrom ? "CD-ROM " : "",
2896 p);
2897 }
2898 kfree(pathbuf);
2899
2900 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2901
2902 wake_up_process(common->thread_task);
2903
2904 return common;
2905
2906error_luns:
2907 common->nluns = i + 1;
2908error_release:
2909 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2910 /* Call fsg_common_release() directly, ref might be not initialised. */
2911 fsg_common_release(&common->ref);
2912 return ERR_PTR(rc);
2913}
2914
2915static void fsg_common_release(struct kref *ref)
2916{
2917 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2918
2919 /* If the thread isn't already dead, tell it to exit now */
2920 if (common->state != FSG_STATE_TERMINATED) {
2921 raise_exception(common, FSG_STATE_EXIT);
2922 wait_for_completion(&common->thread_notifier);
2923 }
2924
2925 if (likely(common->luns)) {
2926 struct fsg_lun *lun = common->luns;
2927 unsigned i = common->nluns;
2928
2929 /* In error recovery common->nluns may be zero. */
2930 for (; i; --i, ++lun) {
2931 device_remove_file(&lun->dev, &dev_attr_nofua);
2932 device_remove_file(&lun->dev, &dev_attr_ro);
2933 device_remove_file(&lun->dev, &dev_attr_file);
2934 fsg_lun_close(lun);
2935 device_unregister(&lun->dev);
2936 }
2937
2938 kfree(common->luns);
2939 }
2940
2941 {
2942 struct fsg_buffhd *bh = common->buffhds;
2943 unsigned i = FSG_NUM_BUFFERS;
2944 do {
2945 kfree(bh->buf);
2946 } while (++bh, --i);
2947 }
2948
2949 if (common->free_storage_on_release)
2950 kfree(common);
2951}
2952
2953
2954/*-------------------------------------------------------------------------*/
2955
2956static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2957{
2958 struct fsg_dev *fsg = fsg_from_func(f);
2959 struct fsg_common *common = fsg->common;
2960
2961 DBG(fsg, "unbind\n");
2962 if (fsg->common->fsg == fsg) {
2963 fsg->common->new_fsg = NULL;
2964 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2965 /* FIXME: make interruptible or killable somehow? */
2966 wait_event(common->fsg_wait, common->fsg != fsg);
2967 }
2968
2969 fsg_common_put(common);
2970 usb_free_descriptors(fsg->function.descriptors);
2971 usb_free_descriptors(fsg->function.hs_descriptors);
2972 kfree(fsg);
2973}
2974
2975static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2976{
2977 struct fsg_dev *fsg = fsg_from_func(f);
2978 struct usb_gadget *gadget = c->cdev->gadget;
2979 int i;
2980 struct usb_ep *ep;
2981
2982 fsg->gadget = gadget;
2983
2984 /* New interface */
2985 i = usb_interface_id(c, f);
2986 if (i < 0)
2987 return i;
2988 fsg_intf_desc.bInterfaceNumber = i;
2989 fsg->interface_number = i;
2990
2991 /* Find all the endpoints we will use */
2992 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2993 if (!ep)
2994 goto autoconf_fail;
2995 ep->driver_data = fsg->common; /* claim the endpoint */
2996 fsg->bulk_in = ep;
2997
2998 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2999 if (!ep)
3000 goto autoconf_fail;
3001 ep->driver_data = fsg->common; /* claim the endpoint */
3002 fsg->bulk_out = ep;
3003
3004 /* Copy descriptors */
3005 f->descriptors = usb_copy_descriptors(fsg_fs_function);
3006 if (unlikely(!f->descriptors))
3007 return -ENOMEM;
3008
3009 if (gadget_is_dualspeed(gadget)) {
3010 /* Assume endpoint addresses are the same for both speeds */
3011 fsg_hs_bulk_in_desc.bEndpointAddress =
3012 fsg_fs_bulk_in_desc.bEndpointAddress;
3013 fsg_hs_bulk_out_desc.bEndpointAddress =
3014 fsg_fs_bulk_out_desc.bEndpointAddress;
3015 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
3016 if (unlikely(!f->hs_descriptors)) {
3017 usb_free_descriptors(f->descriptors);
3018 return -ENOMEM;
3019 }
3020 }
3021
3022 return 0;
3023
3024autoconf_fail:
3025 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3026 return -ENOTSUPP;
3027}
3028
3029
3030/****************************** ADD FUNCTION ******************************/
3031
3032static struct usb_gadget_strings *fsg_strings_array[] = {
3033 &fsg_stringtab,
3034 NULL,
3035};
3036
3037static int fsg_bind_config(struct usb_composite_dev *cdev,
3038 struct usb_configuration *c,
3039 struct fsg_common *common)
3040{
3041 struct fsg_dev *fsg;
3042 int rc;
3043
3044 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3045 if (unlikely(!fsg))
3046 return -ENOMEM;
3047
3048 fsg->function.name = FSG_DRIVER_DESC;
3049 fsg->function.strings = fsg_strings_array;
3050 fsg->function.bind = fsg_bind;
3051 fsg->function.unbind = fsg_unbind;
3052 fsg->function.setup = fsg_setup;
3053 fsg->function.set_alt = fsg_set_alt;
3054 fsg->function.disable = fsg_disable;
3055
3056 fsg->common = common;
3057 /*
3058 * Our caller holds a reference to common structure so we
3059 * don't have to be worry about it being freed until we return
3060 * from this function. So instead of incrementing counter now
3061 * and decrement in error recovery we increment it only when
3062 * call to usb_add_function() was successful.
3063 */
3064
3065 rc = usb_add_function(c, &fsg->function);
3066 if (unlikely(rc))
3067 kfree(fsg);
3068 else
3069 fsg_common_get(fsg->common);
3070 return rc;
3071}
3072
3073static inline int __deprecated __maybe_unused
3074fsg_add(struct usb_composite_dev *cdev, struct usb_configuration *c,
3075 struct fsg_common *common)
3076{
3077 return fsg_bind_config(cdev, c, common);
3078}
3079
3080
3081/************************* Module parameters *************************/
3082
3083struct fsg_module_parameters {
3084 char *file[FSG_MAX_LUNS];
3085 int ro[FSG_MAX_LUNS];
3086 int removable[FSG_MAX_LUNS];
3087 int cdrom[FSG_MAX_LUNS];
3088 int nofua[FSG_MAX_LUNS];
3089
3090 unsigned int file_count, ro_count, removable_count, cdrom_count;
3091 unsigned int nofua_count;
3092 unsigned int luns; /* nluns */
3093 int stall; /* can_stall */
3094};
3095
3096#define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3097 module_param_array_named(prefix ## name, params.name, type, \
3098 &prefix ## params.name ## _count, \
3099 S_IRUGO); \
3100 MODULE_PARM_DESC(prefix ## name, desc)
3101
3102#define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3103 module_param_named(prefix ## name, params.name, type, \
3104 S_IRUGO); \
3105 MODULE_PARM_DESC(prefix ## name, desc)
3106
3107#define FSG_MODULE_PARAMETERS(prefix, params) \
3108 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3109 "names of backing files or devices"); \
3110 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3111 "true to force read-only"); \
3112 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3113 "true to simulate removable media"); \
3114 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3115 "true to simulate CD-ROM instead of disk"); \
3116 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3117 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3118 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3119 "number of LUNs"); \
3120 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3121 "false to prevent bulk stalls")
3122
3123static void
3124fsg_config_from_params(struct fsg_config *cfg,
3125 const struct fsg_module_parameters *params)
3126{
3127 struct fsg_lun_config *lun;
3128 unsigned i;
3129
3130 /* Configure LUNs */
3131 cfg->nluns =
3132 min(params->luns ?: (params->file_count ?: 1u),
3133 (unsigned)FSG_MAX_LUNS);
3134 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3135 lun->ro = !!params->ro[i];
3136 lun->cdrom = !!params->cdrom[i];
3137 lun->removable = /* Removable by default */
3138 params->removable_count <= i || params->removable[i];
3139 lun->filename =
3140 params->file_count > i && params->file[i][0]
3141 ? params->file[i]
3142 : 0;
3143 }
3144
3145 /* Let MSF use defaults */
3146 cfg->lun_name_format = 0;
3147 cfg->thread_name = 0;
3148 cfg->vendor_name = 0;
3149 cfg->product_name = 0;
3150 cfg->release = 0xffff;
3151
3152 cfg->ops = NULL;
3153 cfg->private_data = NULL;
3154
3155 /* Finalise */
3156 cfg->can_stall = params->stall;
3157}
3158
3159static inline struct fsg_common *
3160fsg_common_from_params(struct fsg_common *common,
3161 struct usb_composite_dev *cdev,
3162 const struct fsg_module_parameters *params)
3163 __attribute__((unused));
3164static inline struct fsg_common *
3165fsg_common_from_params(struct fsg_common *common,
3166 struct usb_composite_dev *cdev,
3167 const struct fsg_module_parameters *params)
3168{
3169 struct fsg_config cfg;
3170 fsg_config_from_params(&cfg, params);
3171 return fsg_common_init(common, cdev, &cfg);
3172}
3173
1/*
2 * f_mass_storage.c -- Mass Storage USB Composite Function
3 *
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The names of the above-listed copyright holders may not be used
19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
21 *
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
25 * later version.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
31 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
32 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
33 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
34 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 */
39
40/*
41 * The Mass Storage Function acts as a USB Mass Storage device,
42 * appearing to the host as a disk drive or as a CD-ROM drive. In
43 * addition to providing an example of a genuinely useful composite
44 * function for a USB device, it also illustrates a technique of
45 * double-buffering for increased throughput.
46 *
47 * For more information about MSF and in particular its module
48 * parameters and sysfs interface read the
49 * <Documentation/usb/mass-storage.txt> file.
50 */
51
52/*
53 * MSF is configured by specifying a fsg_config structure. It has the
54 * following fields:
55 *
56 * nluns Number of LUNs function have (anywhere from 1
57 * to FSG_MAX_LUNS which is 8).
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
65 * removable.
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
70 * in R/W mode.
71 * ->removable Flag specifying that LUN shall be indicated as
72 * being removable.
73 * ->cdrom Flag specifying that LUN shall be reported as
74 * being a CD-ROM.
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
77 *
78 * vendor_name
79 * product_name
80 * release Information used as a reply to INQUIRY
81 * request. To use default set to NULL,
82 * NULL, 0xffff respectively. The first
83 * field should be 8 and the second 16
84 * characters or less.
85 *
86 * can_stall Set to permit function to halt bulk endpoints.
87 * Disabled on some USB devices known not
88 * to work correctly. You should set it
89 * to true.
90 *
91 * If "removable" is not set for a LUN then a backing file must be
92 * specified. If it is set, then NULL filename means the LUN's medium
93 * is not loaded (an empty string as "filename" in the fsg_config
94 * structure causes error). The CD-ROM emulation includes a single
95 * data track and no audio tracks; hence there need be only one
96 * backing file per LUN.
97 *
98 * This function is heavily based on "File-backed Storage Gadget" by
99 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
100 * Brownell. The driver's SCSI command interface was based on the
101 * "Information technology - Small Computer System Interface - 2"
102 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
103 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
104 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
105 * was based on the "Universal Serial Bus Mass Storage Class UFI
106 * Command Specification" document, Revision 1.0, December 14, 1998,
107 * available at
108 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
109 */
110
111/*
112 * Driver Design
113 *
114 * The MSF is fairly straightforward. There is a main kernel
115 * thread that handles most of the work. Interrupt routines field
116 * callbacks from the controller driver: bulk- and interrupt-request
117 * completion notifications, endpoint-0 events, and disconnect events.
118 * Completion events are passed to the main thread by wakeup calls. Many
119 * ep0 requests are handled at interrupt time, but SetInterface,
120 * SetConfiguration, and device reset requests are forwarded to the
121 * thread in the form of "exceptions" using SIGUSR1 signals (since they
122 * should interrupt any ongoing file I/O operations).
123 *
124 * The thread's main routine implements the standard command/data/status
125 * parts of a SCSI interaction. It and its subroutines are full of tests
126 * for pending signals/exceptions -- all this polling is necessary since
127 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
128 * indication that the driver really wants to be running in userspace.)
129 * An important point is that so long as the thread is alive it keeps an
130 * open reference to the backing file. This will prevent unmounting
131 * the backing file's underlying filesystem and could cause problems
132 * during system shutdown, for example. To prevent such problems, the
133 * thread catches INT, TERM, and KILL signals and converts them into
134 * an EXIT exception.
135 *
136 * In normal operation the main thread is started during the gadget's
137 * fsg_bind() callback and stopped during fsg_unbind(). But it can
138 * also exit when it receives a signal, and there's no point leaving
139 * the gadget running when the thread is dead. As of this moment, MSF
140 * provides no way to deregister the gadget when thread dies -- maybe
141 * a callback functions is needed.
142 *
143 * To provide maximum throughput, the driver uses a circular pipeline of
144 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
145 * arbitrarily long; in practice the benefits don't justify having more
146 * than 2 stages (i.e., double buffering). But it helps to think of the
147 * pipeline as being a long one. Each buffer head contains a bulk-in and
148 * a bulk-out request pointer (since the buffer can be used for both
149 * output and input -- directions always are given from the host's
150 * point of view) as well as a pointer to the buffer and various state
151 * variables.
152 *
153 * Use of the pipeline follows a simple protocol. There is a variable
154 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
155 * At any time that buffer head may still be in use from an earlier
156 * request, so each buffer head has a state variable indicating whether
157 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
158 * buffer head to be EMPTY, filling the buffer either by file I/O or by
159 * USB I/O (during which the buffer head is BUSY), and marking the buffer
160 * head FULL when the I/O is complete. Then the buffer will be emptied
161 * (again possibly by USB I/O, during which it is marked BUSY) and
162 * finally marked EMPTY again (possibly by a completion routine).
163 *
164 * A module parameter tells the driver to avoid stalling the bulk
165 * endpoints wherever the transport specification allows. This is
166 * necessary for some UDCs like the SuperH, which cannot reliably clear a
167 * halt on a bulk endpoint. However, under certain circumstances the
168 * Bulk-only specification requires a stall. In such cases the driver
169 * will halt the endpoint and set a flag indicating that it should clear
170 * the halt in software during the next device reset. Hopefully this
171 * will permit everything to work correctly. Furthermore, although the
172 * specification allows the bulk-out endpoint to halt when the host sends
173 * too much data, implementing this would cause an unavoidable race.
174 * The driver will always use the "no-stall" approach for OUT transfers.
175 *
176 * One subtle point concerns sending status-stage responses for ep0
177 * requests. Some of these requests, such as device reset, can involve
178 * interrupting an ongoing file I/O operation, which might take an
179 * arbitrarily long time. During that delay the host might give up on
180 * the original ep0 request and issue a new one. When that happens the
181 * driver should not notify the host about completion of the original
182 * request, as the host will no longer be waiting for it. So the driver
183 * assigns to each ep0 request a unique tag, and it keeps track of the
184 * tag value of the request associated with a long-running exception
185 * (device-reset, interface-change, or configuration-change). When the
186 * exception handler is finished, the status-stage response is submitted
187 * only if the current ep0 request tag is equal to the exception request
188 * tag. Thus only the most recently received ep0 request will get a
189 * status-stage response.
190 *
191 * Warning: This driver source file is too long. It ought to be split up
192 * into a header file plus about 3 separate .c files, to handle the details
193 * of the Gadget, USB Mass Storage, and SCSI protocols.
194 */
195
196
197/* #define VERBOSE_DEBUG */
198/* #define DUMP_MSGS */
199
200#include <linux/blkdev.h>
201#include <linux/completion.h>
202#include <linux/dcache.h>
203#include <linux/delay.h>
204#include <linux/device.h>
205#include <linux/fcntl.h>
206#include <linux/file.h>
207#include <linux/fs.h>
208#include <linux/kref.h>
209#include <linux/kthread.h>
210#include <linux/limits.h>
211#include <linux/rwsem.h>
212#include <linux/slab.h>
213#include <linux/spinlock.h>
214#include <linux/string.h>
215#include <linux/freezer.h>
216#include <linux/module.h>
217
218#include <linux/usb/ch9.h>
219#include <linux/usb/gadget.h>
220#include <linux/usb/composite.h>
221
222#include "gadget_chips.h"
223#include "configfs.h"
224
225
226/*------------------------------------------------------------------------*/
227
228#define FSG_DRIVER_DESC "Mass Storage Function"
229#define FSG_DRIVER_VERSION "2009/09/11"
230
231static const char fsg_string_interface[] = "Mass Storage";
232
233#include "storage_common.h"
234#include "f_mass_storage.h"
235
236/* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
237static struct usb_string fsg_strings[] = {
238 {FSG_STRING_INTERFACE, fsg_string_interface},
239 {}
240};
241
242static struct usb_gadget_strings fsg_stringtab = {
243 .language = 0x0409, /* en-us */
244 .strings = fsg_strings,
245};
246
247static struct usb_gadget_strings *fsg_strings_array[] = {
248 &fsg_stringtab,
249 NULL,
250};
251
252/*-------------------------------------------------------------------------*/
253
254struct fsg_dev;
255struct fsg_common;
256
257/* Data shared by all the FSG instances. */
258struct fsg_common {
259 struct usb_gadget *gadget;
260 struct usb_composite_dev *cdev;
261 struct fsg_dev *fsg, *new_fsg;
262 wait_queue_head_t fsg_wait;
263
264 /* filesem protects: backing files in use */
265 struct rw_semaphore filesem;
266
267 /* lock protects: state, all the req_busy's */
268 spinlock_t lock;
269
270 struct usb_ep *ep0; /* Copy of gadget->ep0 */
271 struct usb_request *ep0req; /* Copy of cdev->req */
272 unsigned int ep0_req_tag;
273
274 struct fsg_buffhd *next_buffhd_to_fill;
275 struct fsg_buffhd *next_buffhd_to_drain;
276 struct fsg_buffhd *buffhds;
277 unsigned int fsg_num_buffers;
278
279 int cmnd_size;
280 u8 cmnd[MAX_COMMAND_SIZE];
281
282 unsigned int nluns;
283 unsigned int lun;
284 struct fsg_lun **luns;
285 struct fsg_lun *curlun;
286
287 unsigned int bulk_out_maxpacket;
288 enum fsg_state state; /* For exception handling */
289 unsigned int exception_req_tag;
290
291 enum data_direction data_dir;
292 u32 data_size;
293 u32 data_size_from_cmnd;
294 u32 tag;
295 u32 residue;
296 u32 usb_amount_left;
297
298 unsigned int can_stall:1;
299 unsigned int free_storage_on_release:1;
300 unsigned int phase_error:1;
301 unsigned int short_packet_received:1;
302 unsigned int bad_lun_okay:1;
303 unsigned int running:1;
304 unsigned int sysfs:1;
305
306 int thread_wakeup_needed;
307 struct completion thread_notifier;
308 struct task_struct *thread_task;
309
310 /* Callback functions. */
311 const struct fsg_operations *ops;
312 /* Gadget's private data. */
313 void *private_data;
314
315 /*
316 * Vendor (8 chars), product (16 chars), release (4
317 * hexadecimal digits) and NUL byte
318 */
319 char inquiry_string[8 + 16 + 4 + 1];
320
321 struct kref ref;
322};
323
324struct fsg_dev {
325 struct usb_function function;
326 struct usb_gadget *gadget; /* Copy of cdev->gadget */
327 struct fsg_common *common;
328
329 u16 interface_number;
330
331 unsigned int bulk_in_enabled:1;
332 unsigned int bulk_out_enabled:1;
333
334 unsigned long atomic_bitflags;
335#define IGNORE_BULK_OUT 0
336
337 struct usb_ep *bulk_in;
338 struct usb_ep *bulk_out;
339};
340
341static inline int __fsg_is_set(struct fsg_common *common,
342 const char *func, unsigned line)
343{
344 if (common->fsg)
345 return 1;
346 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
347 WARN_ON(1);
348 return 0;
349}
350
351#define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
352
353static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
354{
355 return container_of(f, struct fsg_dev, function);
356}
357
358typedef void (*fsg_routine_t)(struct fsg_dev *);
359
360static int exception_in_progress(struct fsg_common *common)
361{
362 return common->state > FSG_STATE_IDLE;
363}
364
365/* Make bulk-out requests be divisible by the maxpacket size */
366static void set_bulk_out_req_length(struct fsg_common *common,
367 struct fsg_buffhd *bh, unsigned int length)
368{
369 unsigned int rem;
370
371 bh->bulk_out_intended_length = length;
372 rem = length % common->bulk_out_maxpacket;
373 if (rem > 0)
374 length += common->bulk_out_maxpacket - rem;
375 bh->outreq->length = length;
376}
377
378
379/*-------------------------------------------------------------------------*/
380
381static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
382{
383 const char *name;
384
385 if (ep == fsg->bulk_in)
386 name = "bulk-in";
387 else if (ep == fsg->bulk_out)
388 name = "bulk-out";
389 else
390 name = ep->name;
391 DBG(fsg, "%s set halt\n", name);
392 return usb_ep_set_halt(ep);
393}
394
395
396/*-------------------------------------------------------------------------*/
397
398/* These routines may be called in process context or in_irq */
399
400/* Caller must hold fsg->lock */
401static void wakeup_thread(struct fsg_common *common)
402{
403 smp_wmb(); /* ensure the write of bh->state is complete */
404 /* Tell the main thread that something has happened */
405 common->thread_wakeup_needed = 1;
406 if (common->thread_task)
407 wake_up_process(common->thread_task);
408}
409
410static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
411{
412 unsigned long flags;
413
414 /*
415 * Do nothing if a higher-priority exception is already in progress.
416 * If a lower-or-equal priority exception is in progress, preempt it
417 * and notify the main thread by sending it a signal.
418 */
419 spin_lock_irqsave(&common->lock, flags);
420 if (common->state <= new_state) {
421 common->exception_req_tag = common->ep0_req_tag;
422 common->state = new_state;
423 if (common->thread_task)
424 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
425 common->thread_task);
426 }
427 spin_unlock_irqrestore(&common->lock, flags);
428}
429
430
431/*-------------------------------------------------------------------------*/
432
433static int ep0_queue(struct fsg_common *common)
434{
435 int rc;
436
437 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
438 common->ep0->driver_data = common;
439 if (rc != 0 && rc != -ESHUTDOWN) {
440 /* We can't do much more than wait for a reset */
441 WARNING(common, "error in submission: %s --> %d\n",
442 common->ep0->name, rc);
443 }
444 return rc;
445}
446
447
448/*-------------------------------------------------------------------------*/
449
450/* Completion handlers. These always run in_irq. */
451
452static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
453{
454 struct fsg_common *common = ep->driver_data;
455 struct fsg_buffhd *bh = req->context;
456
457 if (req->status || req->actual != req->length)
458 DBG(common, "%s --> %d, %u/%u\n", __func__,
459 req->status, req->actual, req->length);
460 if (req->status == -ECONNRESET) /* Request was cancelled */
461 usb_ep_fifo_flush(ep);
462
463 /* Hold the lock while we update the request and buffer states */
464 smp_wmb();
465 spin_lock(&common->lock);
466 bh->inreq_busy = 0;
467 bh->state = BUF_STATE_EMPTY;
468 wakeup_thread(common);
469 spin_unlock(&common->lock);
470}
471
472static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
473{
474 struct fsg_common *common = ep->driver_data;
475 struct fsg_buffhd *bh = req->context;
476
477 dump_msg(common, "bulk-out", req->buf, req->actual);
478 if (req->status || req->actual != bh->bulk_out_intended_length)
479 DBG(common, "%s --> %d, %u/%u\n", __func__,
480 req->status, req->actual, bh->bulk_out_intended_length);
481 if (req->status == -ECONNRESET) /* Request was cancelled */
482 usb_ep_fifo_flush(ep);
483
484 /* Hold the lock while we update the request and buffer states */
485 smp_wmb();
486 spin_lock(&common->lock);
487 bh->outreq_busy = 0;
488 bh->state = BUF_STATE_FULL;
489 wakeup_thread(common);
490 spin_unlock(&common->lock);
491}
492
493static int fsg_setup(struct usb_function *f,
494 const struct usb_ctrlrequest *ctrl)
495{
496 struct fsg_dev *fsg = fsg_from_func(f);
497 struct usb_request *req = fsg->common->ep0req;
498 u16 w_index = le16_to_cpu(ctrl->wIndex);
499 u16 w_value = le16_to_cpu(ctrl->wValue);
500 u16 w_length = le16_to_cpu(ctrl->wLength);
501
502 if (!fsg_is_set(fsg->common))
503 return -EOPNOTSUPP;
504
505 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
506 req->context = NULL;
507 req->length = 0;
508 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
509
510 switch (ctrl->bRequest) {
511
512 case US_BULK_RESET_REQUEST:
513 if (ctrl->bRequestType !=
514 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
515 break;
516 if (w_index != fsg->interface_number || w_value != 0 ||
517 w_length != 0)
518 return -EDOM;
519
520 /*
521 * Raise an exception to stop the current operation
522 * and reinitialize our state.
523 */
524 DBG(fsg, "bulk reset request\n");
525 raise_exception(fsg->common, FSG_STATE_RESET);
526 return USB_GADGET_DELAYED_STATUS;
527
528 case US_BULK_GET_MAX_LUN:
529 if (ctrl->bRequestType !=
530 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
531 break;
532 if (w_index != fsg->interface_number || w_value != 0 ||
533 w_length != 1)
534 return -EDOM;
535 VDBG(fsg, "get max LUN\n");
536 *(u8 *)req->buf = fsg->common->nluns - 1;
537
538 /* Respond with data/status */
539 req->length = min((u16)1, w_length);
540 return ep0_queue(fsg->common);
541 }
542
543 VDBG(fsg,
544 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
545 ctrl->bRequestType, ctrl->bRequest,
546 le16_to_cpu(ctrl->wValue), w_index, w_length);
547 return -EOPNOTSUPP;
548}
549
550
551/*-------------------------------------------------------------------------*/
552
553/* All the following routines run in process context */
554
555/* Use this for bulk or interrupt transfers, not ep0 */
556static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
557 struct usb_request *req, int *pbusy,
558 enum fsg_buffer_state *state)
559{
560 int rc;
561
562 if (ep == fsg->bulk_in)
563 dump_msg(fsg, "bulk-in", req->buf, req->length);
564
565 spin_lock_irq(&fsg->common->lock);
566 *pbusy = 1;
567 *state = BUF_STATE_BUSY;
568 spin_unlock_irq(&fsg->common->lock);
569 rc = usb_ep_queue(ep, req, GFP_KERNEL);
570 if (rc != 0) {
571 *pbusy = 0;
572 *state = BUF_STATE_EMPTY;
573
574 /* We can't do much more than wait for a reset */
575
576 /*
577 * Note: currently the net2280 driver fails zero-length
578 * submissions if DMA is enabled.
579 */
580 if (rc != -ESHUTDOWN &&
581 !(rc == -EOPNOTSUPP && req->length == 0))
582 WARNING(fsg, "error in submission: %s --> %d\n",
583 ep->name, rc);
584 }
585}
586
587static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
588{
589 if (!fsg_is_set(common))
590 return false;
591 start_transfer(common->fsg, common->fsg->bulk_in,
592 bh->inreq, &bh->inreq_busy, &bh->state);
593 return true;
594}
595
596static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
597{
598 if (!fsg_is_set(common))
599 return false;
600 start_transfer(common->fsg, common->fsg->bulk_out,
601 bh->outreq, &bh->outreq_busy, &bh->state);
602 return true;
603}
604
605static int sleep_thread(struct fsg_common *common, bool can_freeze)
606{
607 int rc = 0;
608
609 /* Wait until a signal arrives or we are woken up */
610 for (;;) {
611 if (can_freeze)
612 try_to_freeze();
613 set_current_state(TASK_INTERRUPTIBLE);
614 if (signal_pending(current)) {
615 rc = -EINTR;
616 break;
617 }
618 if (common->thread_wakeup_needed)
619 break;
620 schedule();
621 }
622 __set_current_state(TASK_RUNNING);
623 common->thread_wakeup_needed = 0;
624 smp_rmb(); /* ensure the latest bh->state is visible */
625 return rc;
626}
627
628
629/*-------------------------------------------------------------------------*/
630
631static int do_read(struct fsg_common *common)
632{
633 struct fsg_lun *curlun = common->curlun;
634 u32 lba;
635 struct fsg_buffhd *bh;
636 int rc;
637 u32 amount_left;
638 loff_t file_offset, file_offset_tmp;
639 unsigned int amount;
640 ssize_t nread;
641
642 /*
643 * Get the starting Logical Block Address and check that it's
644 * not too big.
645 */
646 if (common->cmnd[0] == READ_6)
647 lba = get_unaligned_be24(&common->cmnd[1]);
648 else {
649 lba = get_unaligned_be32(&common->cmnd[2]);
650
651 /*
652 * We allow DPO (Disable Page Out = don't save data in the
653 * cache) and FUA (Force Unit Access = don't read from the
654 * cache), but we don't implement them.
655 */
656 if ((common->cmnd[1] & ~0x18) != 0) {
657 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
658 return -EINVAL;
659 }
660 }
661 if (lba >= curlun->num_sectors) {
662 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
663 return -EINVAL;
664 }
665 file_offset = ((loff_t) lba) << curlun->blkbits;
666
667 /* Carry out the file reads */
668 amount_left = common->data_size_from_cmnd;
669 if (unlikely(amount_left == 0))
670 return -EIO; /* No default reply */
671
672 for (;;) {
673 /*
674 * Figure out how much we need to read:
675 * Try to read the remaining amount.
676 * But don't read more than the buffer size.
677 * And don't try to read past the end of the file.
678 */
679 amount = min(amount_left, FSG_BUFLEN);
680 amount = min((loff_t)amount,
681 curlun->file_length - file_offset);
682
683 /* Wait for the next buffer to become available */
684 bh = common->next_buffhd_to_fill;
685 while (bh->state != BUF_STATE_EMPTY) {
686 rc = sleep_thread(common, false);
687 if (rc)
688 return rc;
689 }
690
691 /*
692 * If we were asked to read past the end of file,
693 * end with an empty buffer.
694 */
695 if (amount == 0) {
696 curlun->sense_data =
697 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
698 curlun->sense_data_info =
699 file_offset >> curlun->blkbits;
700 curlun->info_valid = 1;
701 bh->inreq->length = 0;
702 bh->state = BUF_STATE_FULL;
703 break;
704 }
705
706 /* Perform the read */
707 file_offset_tmp = file_offset;
708 nread = vfs_read(curlun->filp,
709 (char __user *)bh->buf,
710 amount, &file_offset_tmp);
711 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
712 (unsigned long long)file_offset, (int)nread);
713 if (signal_pending(current))
714 return -EINTR;
715
716 if (nread < 0) {
717 LDBG(curlun, "error in file read: %d\n", (int)nread);
718 nread = 0;
719 } else if (nread < amount) {
720 LDBG(curlun, "partial file read: %d/%u\n",
721 (int)nread, amount);
722 nread = round_down(nread, curlun->blksize);
723 }
724 file_offset += nread;
725 amount_left -= nread;
726 common->residue -= nread;
727
728 /*
729 * Except at the end of the transfer, nread will be
730 * equal to the buffer size, which is divisible by the
731 * bulk-in maxpacket size.
732 */
733 bh->inreq->length = nread;
734 bh->state = BUF_STATE_FULL;
735
736 /* If an error occurred, report it and its position */
737 if (nread < amount) {
738 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
739 curlun->sense_data_info =
740 file_offset >> curlun->blkbits;
741 curlun->info_valid = 1;
742 break;
743 }
744
745 if (amount_left == 0)
746 break; /* No more left to read */
747
748 /* Send this buffer and go read some more */
749 bh->inreq->zero = 0;
750 if (!start_in_transfer(common, bh))
751 /* Don't know what to do if common->fsg is NULL */
752 return -EIO;
753 common->next_buffhd_to_fill = bh->next;
754 }
755
756 return -EIO; /* No default reply */
757}
758
759
760/*-------------------------------------------------------------------------*/
761
762static int do_write(struct fsg_common *common)
763{
764 struct fsg_lun *curlun = common->curlun;
765 u32 lba;
766 struct fsg_buffhd *bh;
767 int get_some_more;
768 u32 amount_left_to_req, amount_left_to_write;
769 loff_t usb_offset, file_offset, file_offset_tmp;
770 unsigned int amount;
771 ssize_t nwritten;
772 int rc;
773
774 if (curlun->ro) {
775 curlun->sense_data = SS_WRITE_PROTECTED;
776 return -EINVAL;
777 }
778 spin_lock(&curlun->filp->f_lock);
779 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
780 spin_unlock(&curlun->filp->f_lock);
781
782 /*
783 * Get the starting Logical Block Address and check that it's
784 * not too big
785 */
786 if (common->cmnd[0] == WRITE_6)
787 lba = get_unaligned_be24(&common->cmnd[1]);
788 else {
789 lba = get_unaligned_be32(&common->cmnd[2]);
790
791 /*
792 * We allow DPO (Disable Page Out = don't save data in the
793 * cache) and FUA (Force Unit Access = write directly to the
794 * medium). We don't implement DPO; we implement FUA by
795 * performing synchronous output.
796 */
797 if (common->cmnd[1] & ~0x18) {
798 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
799 return -EINVAL;
800 }
801 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
802 spin_lock(&curlun->filp->f_lock);
803 curlun->filp->f_flags |= O_SYNC;
804 spin_unlock(&curlun->filp->f_lock);
805 }
806 }
807 if (lba >= curlun->num_sectors) {
808 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
809 return -EINVAL;
810 }
811
812 /* Carry out the file writes */
813 get_some_more = 1;
814 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
815 amount_left_to_req = common->data_size_from_cmnd;
816 amount_left_to_write = common->data_size_from_cmnd;
817
818 while (amount_left_to_write > 0) {
819
820 /* Queue a request for more data from the host */
821 bh = common->next_buffhd_to_fill;
822 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
823
824 /*
825 * Figure out how much we want to get:
826 * Try to get the remaining amount,
827 * but not more than the buffer size.
828 */
829 amount = min(amount_left_to_req, FSG_BUFLEN);
830
831 /* Beyond the end of the backing file? */
832 if (usb_offset >= curlun->file_length) {
833 get_some_more = 0;
834 curlun->sense_data =
835 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
836 curlun->sense_data_info =
837 usb_offset >> curlun->blkbits;
838 curlun->info_valid = 1;
839 continue;
840 }
841
842 /* Get the next buffer */
843 usb_offset += amount;
844 common->usb_amount_left -= amount;
845 amount_left_to_req -= amount;
846 if (amount_left_to_req == 0)
847 get_some_more = 0;
848
849 /*
850 * Except at the end of the transfer, amount will be
851 * equal to the buffer size, which is divisible by
852 * the bulk-out maxpacket size.
853 */
854 set_bulk_out_req_length(common, bh, amount);
855 if (!start_out_transfer(common, bh))
856 /* Dunno what to do if common->fsg is NULL */
857 return -EIO;
858 common->next_buffhd_to_fill = bh->next;
859 continue;
860 }
861
862 /* Write the received data to the backing file */
863 bh = common->next_buffhd_to_drain;
864 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
865 break; /* We stopped early */
866 if (bh->state == BUF_STATE_FULL) {
867 smp_rmb();
868 common->next_buffhd_to_drain = bh->next;
869 bh->state = BUF_STATE_EMPTY;
870
871 /* Did something go wrong with the transfer? */
872 if (bh->outreq->status != 0) {
873 curlun->sense_data = SS_COMMUNICATION_FAILURE;
874 curlun->sense_data_info =
875 file_offset >> curlun->blkbits;
876 curlun->info_valid = 1;
877 break;
878 }
879
880 amount = bh->outreq->actual;
881 if (curlun->file_length - file_offset < amount) {
882 LERROR(curlun,
883 "write %u @ %llu beyond end %llu\n",
884 amount, (unsigned long long)file_offset,
885 (unsigned long long)curlun->file_length);
886 amount = curlun->file_length - file_offset;
887 }
888
889 /* Don't accept excess data. The spec doesn't say
890 * what to do in this case. We'll ignore the error.
891 */
892 amount = min(amount, bh->bulk_out_intended_length);
893
894 /* Don't write a partial block */
895 amount = round_down(amount, curlun->blksize);
896 if (amount == 0)
897 goto empty_write;
898
899 /* Perform the write */
900 file_offset_tmp = file_offset;
901 nwritten = vfs_write(curlun->filp,
902 (char __user *)bh->buf,
903 amount, &file_offset_tmp);
904 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
905 (unsigned long long)file_offset, (int)nwritten);
906 if (signal_pending(current))
907 return -EINTR; /* Interrupted! */
908
909 if (nwritten < 0) {
910 LDBG(curlun, "error in file write: %d\n",
911 (int)nwritten);
912 nwritten = 0;
913 } else if (nwritten < amount) {
914 LDBG(curlun, "partial file write: %d/%u\n",
915 (int)nwritten, amount);
916 nwritten = round_down(nwritten, curlun->blksize);
917 }
918 file_offset += nwritten;
919 amount_left_to_write -= nwritten;
920 common->residue -= nwritten;
921
922 /* If an error occurred, report it and its position */
923 if (nwritten < amount) {
924 curlun->sense_data = SS_WRITE_ERROR;
925 curlun->sense_data_info =
926 file_offset >> curlun->blkbits;
927 curlun->info_valid = 1;
928 break;
929 }
930
931 empty_write:
932 /* Did the host decide to stop early? */
933 if (bh->outreq->actual < bh->bulk_out_intended_length) {
934 common->short_packet_received = 1;
935 break;
936 }
937 continue;
938 }
939
940 /* Wait for something to happen */
941 rc = sleep_thread(common, false);
942 if (rc)
943 return rc;
944 }
945
946 return -EIO; /* No default reply */
947}
948
949
950/*-------------------------------------------------------------------------*/
951
952static int do_synchronize_cache(struct fsg_common *common)
953{
954 struct fsg_lun *curlun = common->curlun;
955 int rc;
956
957 /* We ignore the requested LBA and write out all file's
958 * dirty data buffers. */
959 rc = fsg_lun_fsync_sub(curlun);
960 if (rc)
961 curlun->sense_data = SS_WRITE_ERROR;
962 return 0;
963}
964
965
966/*-------------------------------------------------------------------------*/
967
968static void invalidate_sub(struct fsg_lun *curlun)
969{
970 struct file *filp = curlun->filp;
971 struct inode *inode = file_inode(filp);
972 unsigned long rc;
973
974 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
975 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
976}
977
978static int do_verify(struct fsg_common *common)
979{
980 struct fsg_lun *curlun = common->curlun;
981 u32 lba;
982 u32 verification_length;
983 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
984 loff_t file_offset, file_offset_tmp;
985 u32 amount_left;
986 unsigned int amount;
987 ssize_t nread;
988
989 /*
990 * Get the starting Logical Block Address and check that it's
991 * not too big.
992 */
993 lba = get_unaligned_be32(&common->cmnd[2]);
994 if (lba >= curlun->num_sectors) {
995 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
996 return -EINVAL;
997 }
998
999 /*
1000 * We allow DPO (Disable Page Out = don't save data in the
1001 * cache) but we don't implement it.
1002 */
1003 if (common->cmnd[1] & ~0x10) {
1004 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1005 return -EINVAL;
1006 }
1007
1008 verification_length = get_unaligned_be16(&common->cmnd[7]);
1009 if (unlikely(verification_length == 0))
1010 return -EIO; /* No default reply */
1011
1012 /* Prepare to carry out the file verify */
1013 amount_left = verification_length << curlun->blkbits;
1014 file_offset = ((loff_t) lba) << curlun->blkbits;
1015
1016 /* Write out all the dirty buffers before invalidating them */
1017 fsg_lun_fsync_sub(curlun);
1018 if (signal_pending(current))
1019 return -EINTR;
1020
1021 invalidate_sub(curlun);
1022 if (signal_pending(current))
1023 return -EINTR;
1024
1025 /* Just try to read the requested blocks */
1026 while (amount_left > 0) {
1027 /*
1028 * Figure out how much we need to read:
1029 * Try to read the remaining amount, but not more than
1030 * the buffer size.
1031 * And don't try to read past the end of the file.
1032 */
1033 amount = min(amount_left, FSG_BUFLEN);
1034 amount = min((loff_t)amount,
1035 curlun->file_length - file_offset);
1036 if (amount == 0) {
1037 curlun->sense_data =
1038 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1039 curlun->sense_data_info =
1040 file_offset >> curlun->blkbits;
1041 curlun->info_valid = 1;
1042 break;
1043 }
1044
1045 /* Perform the read */
1046 file_offset_tmp = file_offset;
1047 nread = vfs_read(curlun->filp,
1048 (char __user *) bh->buf,
1049 amount, &file_offset_tmp);
1050 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1051 (unsigned long long) file_offset,
1052 (int) nread);
1053 if (signal_pending(current))
1054 return -EINTR;
1055
1056 if (nread < 0) {
1057 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1058 nread = 0;
1059 } else if (nread < amount) {
1060 LDBG(curlun, "partial file verify: %d/%u\n",
1061 (int)nread, amount);
1062 nread = round_down(nread, curlun->blksize);
1063 }
1064 if (nread == 0) {
1065 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1066 curlun->sense_data_info =
1067 file_offset >> curlun->blkbits;
1068 curlun->info_valid = 1;
1069 break;
1070 }
1071 file_offset += nread;
1072 amount_left -= nread;
1073 }
1074 return 0;
1075}
1076
1077
1078/*-------------------------------------------------------------------------*/
1079
1080static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1081{
1082 struct fsg_lun *curlun = common->curlun;
1083 u8 *buf = (u8 *) bh->buf;
1084
1085 if (!curlun) { /* Unsupported LUNs are okay */
1086 common->bad_lun_okay = 1;
1087 memset(buf, 0, 36);
1088 buf[0] = 0x7f; /* Unsupported, no device-type */
1089 buf[4] = 31; /* Additional length */
1090 return 36;
1091 }
1092
1093 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1094 buf[1] = curlun->removable ? 0x80 : 0;
1095 buf[2] = 2; /* ANSI SCSI level 2 */
1096 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1097 buf[4] = 31; /* Additional length */
1098 buf[5] = 0; /* No special options */
1099 buf[6] = 0;
1100 buf[7] = 0;
1101 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1102 return 36;
1103}
1104
1105static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1106{
1107 struct fsg_lun *curlun = common->curlun;
1108 u8 *buf = (u8 *) bh->buf;
1109 u32 sd, sdinfo;
1110 int valid;
1111
1112 /*
1113 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1114 *
1115 * If a REQUEST SENSE command is received from an initiator
1116 * with a pending unit attention condition (before the target
1117 * generates the contingent allegiance condition), then the
1118 * target shall either:
1119 * a) report any pending sense data and preserve the unit
1120 * attention condition on the logical unit, or,
1121 * b) report the unit attention condition, may discard any
1122 * pending sense data, and clear the unit attention
1123 * condition on the logical unit for that initiator.
1124 *
1125 * FSG normally uses option a); enable this code to use option b).
1126 */
1127#if 0
1128 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1129 curlun->sense_data = curlun->unit_attention_data;
1130 curlun->unit_attention_data = SS_NO_SENSE;
1131 }
1132#endif
1133
1134 if (!curlun) { /* Unsupported LUNs are okay */
1135 common->bad_lun_okay = 1;
1136 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1137 sdinfo = 0;
1138 valid = 0;
1139 } else {
1140 sd = curlun->sense_data;
1141 sdinfo = curlun->sense_data_info;
1142 valid = curlun->info_valid << 7;
1143 curlun->sense_data = SS_NO_SENSE;
1144 curlun->sense_data_info = 0;
1145 curlun->info_valid = 0;
1146 }
1147
1148 memset(buf, 0, 18);
1149 buf[0] = valid | 0x70; /* Valid, current error */
1150 buf[2] = SK(sd);
1151 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1152 buf[7] = 18 - 8; /* Additional sense length */
1153 buf[12] = ASC(sd);
1154 buf[13] = ASCQ(sd);
1155 return 18;
1156}
1157
1158static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1159{
1160 struct fsg_lun *curlun = common->curlun;
1161 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1162 int pmi = common->cmnd[8];
1163 u8 *buf = (u8 *)bh->buf;
1164
1165 /* Check the PMI and LBA fields */
1166 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1167 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1168 return -EINVAL;
1169 }
1170
1171 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1172 /* Max logical block */
1173 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1174 return 8;
1175}
1176
1177static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1178{
1179 struct fsg_lun *curlun = common->curlun;
1180 int msf = common->cmnd[1] & 0x02;
1181 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1182 u8 *buf = (u8 *)bh->buf;
1183
1184 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1185 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1186 return -EINVAL;
1187 }
1188 if (lba >= curlun->num_sectors) {
1189 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1190 return -EINVAL;
1191 }
1192
1193 memset(buf, 0, 8);
1194 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1195 store_cdrom_address(&buf[4], msf, lba);
1196 return 8;
1197}
1198
1199static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1200{
1201 struct fsg_lun *curlun = common->curlun;
1202 int msf = common->cmnd[1] & 0x02;
1203 int start_track = common->cmnd[6];
1204 u8 *buf = (u8 *)bh->buf;
1205
1206 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1207 start_track > 1) {
1208 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1209 return -EINVAL;
1210 }
1211
1212 memset(buf, 0, 20);
1213 buf[1] = (20-2); /* TOC data length */
1214 buf[2] = 1; /* First track number */
1215 buf[3] = 1; /* Last track number */
1216 buf[5] = 0x16; /* Data track, copying allowed */
1217 buf[6] = 0x01; /* Only track is number 1 */
1218 store_cdrom_address(&buf[8], msf, 0);
1219
1220 buf[13] = 0x16; /* Lead-out track is data */
1221 buf[14] = 0xAA; /* Lead-out track number */
1222 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1223 return 20;
1224}
1225
1226static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1227{
1228 struct fsg_lun *curlun = common->curlun;
1229 int mscmnd = common->cmnd[0];
1230 u8 *buf = (u8 *) bh->buf;
1231 u8 *buf0 = buf;
1232 int pc, page_code;
1233 int changeable_values, all_pages;
1234 int valid_page = 0;
1235 int len, limit;
1236
1237 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1238 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1239 return -EINVAL;
1240 }
1241 pc = common->cmnd[2] >> 6;
1242 page_code = common->cmnd[2] & 0x3f;
1243 if (pc == 3) {
1244 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1245 return -EINVAL;
1246 }
1247 changeable_values = (pc == 1);
1248 all_pages = (page_code == 0x3f);
1249
1250 /*
1251 * Write the mode parameter header. Fixed values are: default
1252 * medium type, no cache control (DPOFUA), and no block descriptors.
1253 * The only variable value is the WriteProtect bit. We will fill in
1254 * the mode data length later.
1255 */
1256 memset(buf, 0, 8);
1257 if (mscmnd == MODE_SENSE) {
1258 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1259 buf += 4;
1260 limit = 255;
1261 } else { /* MODE_SENSE_10 */
1262 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1263 buf += 8;
1264 limit = 65535; /* Should really be FSG_BUFLEN */
1265 }
1266
1267 /* No block descriptors */
1268
1269 /*
1270 * The mode pages, in numerical order. The only page we support
1271 * is the Caching page.
1272 */
1273 if (page_code == 0x08 || all_pages) {
1274 valid_page = 1;
1275 buf[0] = 0x08; /* Page code */
1276 buf[1] = 10; /* Page length */
1277 memset(buf+2, 0, 10); /* None of the fields are changeable */
1278
1279 if (!changeable_values) {
1280 buf[2] = 0x04; /* Write cache enable, */
1281 /* Read cache not disabled */
1282 /* No cache retention priorities */
1283 put_unaligned_be16(0xffff, &buf[4]);
1284 /* Don't disable prefetch */
1285 /* Minimum prefetch = 0 */
1286 put_unaligned_be16(0xffff, &buf[8]);
1287 /* Maximum prefetch */
1288 put_unaligned_be16(0xffff, &buf[10]);
1289 /* Maximum prefetch ceiling */
1290 }
1291 buf += 12;
1292 }
1293
1294 /*
1295 * Check that a valid page was requested and the mode data length
1296 * isn't too long.
1297 */
1298 len = buf - buf0;
1299 if (!valid_page || len > limit) {
1300 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1301 return -EINVAL;
1302 }
1303
1304 /* Store the mode data length */
1305 if (mscmnd == MODE_SENSE)
1306 buf0[0] = len - 1;
1307 else
1308 put_unaligned_be16(len - 2, buf0);
1309 return len;
1310}
1311
1312static int do_start_stop(struct fsg_common *common)
1313{
1314 struct fsg_lun *curlun = common->curlun;
1315 int loej, start;
1316
1317 if (!curlun) {
1318 return -EINVAL;
1319 } else if (!curlun->removable) {
1320 curlun->sense_data = SS_INVALID_COMMAND;
1321 return -EINVAL;
1322 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1323 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1324 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1325 return -EINVAL;
1326 }
1327
1328 loej = common->cmnd[4] & 0x02;
1329 start = common->cmnd[4] & 0x01;
1330
1331 /*
1332 * Our emulation doesn't support mounting; the medium is
1333 * available for use as soon as it is loaded.
1334 */
1335 if (start) {
1336 if (!fsg_lun_is_open(curlun)) {
1337 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1338 return -EINVAL;
1339 }
1340 return 0;
1341 }
1342
1343 /* Are we allowed to unload the media? */
1344 if (curlun->prevent_medium_removal) {
1345 LDBG(curlun, "unload attempt prevented\n");
1346 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1347 return -EINVAL;
1348 }
1349
1350 if (!loej)
1351 return 0;
1352
1353 up_read(&common->filesem);
1354 down_write(&common->filesem);
1355 fsg_lun_close(curlun);
1356 up_write(&common->filesem);
1357 down_read(&common->filesem);
1358
1359 return 0;
1360}
1361
1362static int do_prevent_allow(struct fsg_common *common)
1363{
1364 struct fsg_lun *curlun = common->curlun;
1365 int prevent;
1366
1367 if (!common->curlun) {
1368 return -EINVAL;
1369 } else if (!common->curlun->removable) {
1370 common->curlun->sense_data = SS_INVALID_COMMAND;
1371 return -EINVAL;
1372 }
1373
1374 prevent = common->cmnd[4] & 0x01;
1375 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1376 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1377 return -EINVAL;
1378 }
1379
1380 if (curlun->prevent_medium_removal && !prevent)
1381 fsg_lun_fsync_sub(curlun);
1382 curlun->prevent_medium_removal = prevent;
1383 return 0;
1384}
1385
1386static int do_read_format_capacities(struct fsg_common *common,
1387 struct fsg_buffhd *bh)
1388{
1389 struct fsg_lun *curlun = common->curlun;
1390 u8 *buf = (u8 *) bh->buf;
1391
1392 buf[0] = buf[1] = buf[2] = 0;
1393 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1394 buf += 4;
1395
1396 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1397 /* Number of blocks */
1398 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1399 buf[4] = 0x02; /* Current capacity */
1400 return 12;
1401}
1402
1403static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1404{
1405 struct fsg_lun *curlun = common->curlun;
1406
1407 /* We don't support MODE SELECT */
1408 if (curlun)
1409 curlun->sense_data = SS_INVALID_COMMAND;
1410 return -EINVAL;
1411}
1412
1413
1414/*-------------------------------------------------------------------------*/
1415
1416static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1417{
1418 int rc;
1419
1420 rc = fsg_set_halt(fsg, fsg->bulk_in);
1421 if (rc == -EAGAIN)
1422 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1423 while (rc != 0) {
1424 if (rc != -EAGAIN) {
1425 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1426 rc = 0;
1427 break;
1428 }
1429
1430 /* Wait for a short time and then try again */
1431 if (msleep_interruptible(100) != 0)
1432 return -EINTR;
1433 rc = usb_ep_set_halt(fsg->bulk_in);
1434 }
1435 return rc;
1436}
1437
1438static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1439{
1440 int rc;
1441
1442 DBG(fsg, "bulk-in set wedge\n");
1443 rc = usb_ep_set_wedge(fsg->bulk_in);
1444 if (rc == -EAGAIN)
1445 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1446 while (rc != 0) {
1447 if (rc != -EAGAIN) {
1448 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1449 rc = 0;
1450 break;
1451 }
1452
1453 /* Wait for a short time and then try again */
1454 if (msleep_interruptible(100) != 0)
1455 return -EINTR;
1456 rc = usb_ep_set_wedge(fsg->bulk_in);
1457 }
1458 return rc;
1459}
1460
1461static int throw_away_data(struct fsg_common *common)
1462{
1463 struct fsg_buffhd *bh;
1464 u32 amount;
1465 int rc;
1466
1467 for (bh = common->next_buffhd_to_drain;
1468 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1469 bh = common->next_buffhd_to_drain) {
1470
1471 /* Throw away the data in a filled buffer */
1472 if (bh->state == BUF_STATE_FULL) {
1473 smp_rmb();
1474 bh->state = BUF_STATE_EMPTY;
1475 common->next_buffhd_to_drain = bh->next;
1476
1477 /* A short packet or an error ends everything */
1478 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1479 bh->outreq->status != 0) {
1480 raise_exception(common,
1481 FSG_STATE_ABORT_BULK_OUT);
1482 return -EINTR;
1483 }
1484 continue;
1485 }
1486
1487 /* Try to submit another request if we need one */
1488 bh = common->next_buffhd_to_fill;
1489 if (bh->state == BUF_STATE_EMPTY
1490 && common->usb_amount_left > 0) {
1491 amount = min(common->usb_amount_left, FSG_BUFLEN);
1492
1493 /*
1494 * Except at the end of the transfer, amount will be
1495 * equal to the buffer size, which is divisible by
1496 * the bulk-out maxpacket size.
1497 */
1498 set_bulk_out_req_length(common, bh, amount);
1499 if (!start_out_transfer(common, bh))
1500 /* Dunno what to do if common->fsg is NULL */
1501 return -EIO;
1502 common->next_buffhd_to_fill = bh->next;
1503 common->usb_amount_left -= amount;
1504 continue;
1505 }
1506
1507 /* Otherwise wait for something to happen */
1508 rc = sleep_thread(common, true);
1509 if (rc)
1510 return rc;
1511 }
1512 return 0;
1513}
1514
1515static int finish_reply(struct fsg_common *common)
1516{
1517 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1518 int rc = 0;
1519
1520 switch (common->data_dir) {
1521 case DATA_DIR_NONE:
1522 break; /* Nothing to send */
1523
1524 /*
1525 * If we don't know whether the host wants to read or write,
1526 * this must be CB or CBI with an unknown command. We mustn't
1527 * try to send or receive any data. So stall both bulk pipes
1528 * if we can and wait for a reset.
1529 */
1530 case DATA_DIR_UNKNOWN:
1531 if (!common->can_stall) {
1532 /* Nothing */
1533 } else if (fsg_is_set(common)) {
1534 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1535 rc = halt_bulk_in_endpoint(common->fsg);
1536 } else {
1537 /* Don't know what to do if common->fsg is NULL */
1538 rc = -EIO;
1539 }
1540 break;
1541
1542 /* All but the last buffer of data must have already been sent */
1543 case DATA_DIR_TO_HOST:
1544 if (common->data_size == 0) {
1545 /* Nothing to send */
1546
1547 /* Don't know what to do if common->fsg is NULL */
1548 } else if (!fsg_is_set(common)) {
1549 rc = -EIO;
1550
1551 /* If there's no residue, simply send the last buffer */
1552 } else if (common->residue == 0) {
1553 bh->inreq->zero = 0;
1554 if (!start_in_transfer(common, bh))
1555 return -EIO;
1556 common->next_buffhd_to_fill = bh->next;
1557
1558 /*
1559 * For Bulk-only, mark the end of the data with a short
1560 * packet. If we are allowed to stall, halt the bulk-in
1561 * endpoint. (Note: This violates the Bulk-Only Transport
1562 * specification, which requires us to pad the data if we
1563 * don't halt the endpoint. Presumably nobody will mind.)
1564 */
1565 } else {
1566 bh->inreq->zero = 1;
1567 if (!start_in_transfer(common, bh))
1568 rc = -EIO;
1569 common->next_buffhd_to_fill = bh->next;
1570 if (common->can_stall)
1571 rc = halt_bulk_in_endpoint(common->fsg);
1572 }
1573 break;
1574
1575 /*
1576 * We have processed all we want from the data the host has sent.
1577 * There may still be outstanding bulk-out requests.
1578 */
1579 case DATA_DIR_FROM_HOST:
1580 if (common->residue == 0) {
1581 /* Nothing to receive */
1582
1583 /* Did the host stop sending unexpectedly early? */
1584 } else if (common->short_packet_received) {
1585 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1586 rc = -EINTR;
1587
1588 /*
1589 * We haven't processed all the incoming data. Even though
1590 * we may be allowed to stall, doing so would cause a race.
1591 * The controller may already have ACK'ed all the remaining
1592 * bulk-out packets, in which case the host wouldn't see a
1593 * STALL. Not realizing the endpoint was halted, it wouldn't
1594 * clear the halt -- leading to problems later on.
1595 */
1596#if 0
1597 } else if (common->can_stall) {
1598 if (fsg_is_set(common))
1599 fsg_set_halt(common->fsg,
1600 common->fsg->bulk_out);
1601 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1602 rc = -EINTR;
1603#endif
1604
1605 /*
1606 * We can't stall. Read in the excess data and throw it
1607 * all away.
1608 */
1609 } else {
1610 rc = throw_away_data(common);
1611 }
1612 break;
1613 }
1614 return rc;
1615}
1616
1617static int send_status(struct fsg_common *common)
1618{
1619 struct fsg_lun *curlun = common->curlun;
1620 struct fsg_buffhd *bh;
1621 struct bulk_cs_wrap *csw;
1622 int rc;
1623 u8 status = US_BULK_STAT_OK;
1624 u32 sd, sdinfo = 0;
1625
1626 /* Wait for the next buffer to become available */
1627 bh = common->next_buffhd_to_fill;
1628 while (bh->state != BUF_STATE_EMPTY) {
1629 rc = sleep_thread(common, true);
1630 if (rc)
1631 return rc;
1632 }
1633
1634 if (curlun) {
1635 sd = curlun->sense_data;
1636 sdinfo = curlun->sense_data_info;
1637 } else if (common->bad_lun_okay)
1638 sd = SS_NO_SENSE;
1639 else
1640 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1641
1642 if (common->phase_error) {
1643 DBG(common, "sending phase-error status\n");
1644 status = US_BULK_STAT_PHASE;
1645 sd = SS_INVALID_COMMAND;
1646 } else if (sd != SS_NO_SENSE) {
1647 DBG(common, "sending command-failure status\n");
1648 status = US_BULK_STAT_FAIL;
1649 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1650 " info x%x\n",
1651 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1652 }
1653
1654 /* Store and send the Bulk-only CSW */
1655 csw = (void *)bh->buf;
1656
1657 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1658 csw->Tag = common->tag;
1659 csw->Residue = cpu_to_le32(common->residue);
1660 csw->Status = status;
1661
1662 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1663 bh->inreq->zero = 0;
1664 if (!start_in_transfer(common, bh))
1665 /* Don't know what to do if common->fsg is NULL */
1666 return -EIO;
1667
1668 common->next_buffhd_to_fill = bh->next;
1669 return 0;
1670}
1671
1672
1673/*-------------------------------------------------------------------------*/
1674
1675/*
1676 * Check whether the command is properly formed and whether its data size
1677 * and direction agree with the values we already have.
1678 */
1679static int check_command(struct fsg_common *common, int cmnd_size,
1680 enum data_direction data_dir, unsigned int mask,
1681 int needs_medium, const char *name)
1682{
1683 int i;
1684 unsigned int lun = common->cmnd[1] >> 5;
1685 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1686 char hdlen[20];
1687 struct fsg_lun *curlun;
1688
1689 hdlen[0] = 0;
1690 if (common->data_dir != DATA_DIR_UNKNOWN)
1691 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1692 common->data_size);
1693 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1694 name, cmnd_size, dirletter[(int) data_dir],
1695 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1696
1697 /*
1698 * We can't reply at all until we know the correct data direction
1699 * and size.
1700 */
1701 if (common->data_size_from_cmnd == 0)
1702 data_dir = DATA_DIR_NONE;
1703 if (common->data_size < common->data_size_from_cmnd) {
1704 /*
1705 * Host data size < Device data size is a phase error.
1706 * Carry out the command, but only transfer as much as
1707 * we are allowed.
1708 */
1709 common->data_size_from_cmnd = common->data_size;
1710 common->phase_error = 1;
1711 }
1712 common->residue = common->data_size;
1713 common->usb_amount_left = common->data_size;
1714
1715 /* Conflicting data directions is a phase error */
1716 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1717 common->phase_error = 1;
1718 return -EINVAL;
1719 }
1720
1721 /* Verify the length of the command itself */
1722 if (cmnd_size != common->cmnd_size) {
1723
1724 /*
1725 * Special case workaround: There are plenty of buggy SCSI
1726 * implementations. Many have issues with cbw->Length
1727 * field passing a wrong command size. For those cases we
1728 * always try to work around the problem by using the length
1729 * sent by the host side provided it is at least as large
1730 * as the correct command length.
1731 * Examples of such cases would be MS-Windows, which issues
1732 * REQUEST SENSE with cbw->Length == 12 where it should
1733 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1734 * REQUEST SENSE with cbw->Length == 10 where it should
1735 * be 6 as well.
1736 */
1737 if (cmnd_size <= common->cmnd_size) {
1738 DBG(common, "%s is buggy! Expected length %d "
1739 "but we got %d\n", name,
1740 cmnd_size, common->cmnd_size);
1741 cmnd_size = common->cmnd_size;
1742 } else {
1743 common->phase_error = 1;
1744 return -EINVAL;
1745 }
1746 }
1747
1748 /* Check that the LUN values are consistent */
1749 if (common->lun != lun)
1750 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1751 common->lun, lun);
1752
1753 /* Check the LUN */
1754 curlun = common->curlun;
1755 if (curlun) {
1756 if (common->cmnd[0] != REQUEST_SENSE) {
1757 curlun->sense_data = SS_NO_SENSE;
1758 curlun->sense_data_info = 0;
1759 curlun->info_valid = 0;
1760 }
1761 } else {
1762 common->bad_lun_okay = 0;
1763
1764 /*
1765 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1766 * to use unsupported LUNs; all others may not.
1767 */
1768 if (common->cmnd[0] != INQUIRY &&
1769 common->cmnd[0] != REQUEST_SENSE) {
1770 DBG(common, "unsupported LUN %u\n", common->lun);
1771 return -EINVAL;
1772 }
1773 }
1774
1775 /*
1776 * If a unit attention condition exists, only INQUIRY and
1777 * REQUEST SENSE commands are allowed; anything else must fail.
1778 */
1779 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1780 common->cmnd[0] != INQUIRY &&
1781 common->cmnd[0] != REQUEST_SENSE) {
1782 curlun->sense_data = curlun->unit_attention_data;
1783 curlun->unit_attention_data = SS_NO_SENSE;
1784 return -EINVAL;
1785 }
1786
1787 /* Check that only command bytes listed in the mask are non-zero */
1788 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1789 for (i = 1; i < cmnd_size; ++i) {
1790 if (common->cmnd[i] && !(mask & (1 << i))) {
1791 if (curlun)
1792 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1793 return -EINVAL;
1794 }
1795 }
1796
1797 /* If the medium isn't mounted and the command needs to access
1798 * it, return an error. */
1799 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1800 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1801 return -EINVAL;
1802 }
1803
1804 return 0;
1805}
1806
1807/* wrapper of check_command for data size in blocks handling */
1808static int check_command_size_in_blocks(struct fsg_common *common,
1809 int cmnd_size, enum data_direction data_dir,
1810 unsigned int mask, int needs_medium, const char *name)
1811{
1812 if (common->curlun)
1813 common->data_size_from_cmnd <<= common->curlun->blkbits;
1814 return check_command(common, cmnd_size, data_dir,
1815 mask, needs_medium, name);
1816}
1817
1818static int do_scsi_command(struct fsg_common *common)
1819{
1820 struct fsg_buffhd *bh;
1821 int rc;
1822 int reply = -EINVAL;
1823 int i;
1824 static char unknown[16];
1825
1826 dump_cdb(common);
1827
1828 /* Wait for the next buffer to become available for data or status */
1829 bh = common->next_buffhd_to_fill;
1830 common->next_buffhd_to_drain = bh;
1831 while (bh->state != BUF_STATE_EMPTY) {
1832 rc = sleep_thread(common, true);
1833 if (rc)
1834 return rc;
1835 }
1836 common->phase_error = 0;
1837 common->short_packet_received = 0;
1838
1839 down_read(&common->filesem); /* We're using the backing file */
1840 switch (common->cmnd[0]) {
1841
1842 case INQUIRY:
1843 common->data_size_from_cmnd = common->cmnd[4];
1844 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1845 (1<<4), 0,
1846 "INQUIRY");
1847 if (reply == 0)
1848 reply = do_inquiry(common, bh);
1849 break;
1850
1851 case MODE_SELECT:
1852 common->data_size_from_cmnd = common->cmnd[4];
1853 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1854 (1<<1) | (1<<4), 0,
1855 "MODE SELECT(6)");
1856 if (reply == 0)
1857 reply = do_mode_select(common, bh);
1858 break;
1859
1860 case MODE_SELECT_10:
1861 common->data_size_from_cmnd =
1862 get_unaligned_be16(&common->cmnd[7]);
1863 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1864 (1<<1) | (3<<7), 0,
1865 "MODE SELECT(10)");
1866 if (reply == 0)
1867 reply = do_mode_select(common, bh);
1868 break;
1869
1870 case MODE_SENSE:
1871 common->data_size_from_cmnd = common->cmnd[4];
1872 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1873 (1<<1) | (1<<2) | (1<<4), 0,
1874 "MODE SENSE(6)");
1875 if (reply == 0)
1876 reply = do_mode_sense(common, bh);
1877 break;
1878
1879 case MODE_SENSE_10:
1880 common->data_size_from_cmnd =
1881 get_unaligned_be16(&common->cmnd[7]);
1882 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1883 (1<<1) | (1<<2) | (3<<7), 0,
1884 "MODE SENSE(10)");
1885 if (reply == 0)
1886 reply = do_mode_sense(common, bh);
1887 break;
1888
1889 case ALLOW_MEDIUM_REMOVAL:
1890 common->data_size_from_cmnd = 0;
1891 reply = check_command(common, 6, DATA_DIR_NONE,
1892 (1<<4), 0,
1893 "PREVENT-ALLOW MEDIUM REMOVAL");
1894 if (reply == 0)
1895 reply = do_prevent_allow(common);
1896 break;
1897
1898 case READ_6:
1899 i = common->cmnd[4];
1900 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1901 reply = check_command_size_in_blocks(common, 6,
1902 DATA_DIR_TO_HOST,
1903 (7<<1) | (1<<4), 1,
1904 "READ(6)");
1905 if (reply == 0)
1906 reply = do_read(common);
1907 break;
1908
1909 case READ_10:
1910 common->data_size_from_cmnd =
1911 get_unaligned_be16(&common->cmnd[7]);
1912 reply = check_command_size_in_blocks(common, 10,
1913 DATA_DIR_TO_HOST,
1914 (1<<1) | (0xf<<2) | (3<<7), 1,
1915 "READ(10)");
1916 if (reply == 0)
1917 reply = do_read(common);
1918 break;
1919
1920 case READ_12:
1921 common->data_size_from_cmnd =
1922 get_unaligned_be32(&common->cmnd[6]);
1923 reply = check_command_size_in_blocks(common, 12,
1924 DATA_DIR_TO_HOST,
1925 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1926 "READ(12)");
1927 if (reply == 0)
1928 reply = do_read(common);
1929 break;
1930
1931 case READ_CAPACITY:
1932 common->data_size_from_cmnd = 8;
1933 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1934 (0xf<<2) | (1<<8), 1,
1935 "READ CAPACITY");
1936 if (reply == 0)
1937 reply = do_read_capacity(common, bh);
1938 break;
1939
1940 case READ_HEADER:
1941 if (!common->curlun || !common->curlun->cdrom)
1942 goto unknown_cmnd;
1943 common->data_size_from_cmnd =
1944 get_unaligned_be16(&common->cmnd[7]);
1945 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1946 (3<<7) | (0x1f<<1), 1,
1947 "READ HEADER");
1948 if (reply == 0)
1949 reply = do_read_header(common, bh);
1950 break;
1951
1952 case READ_TOC:
1953 if (!common->curlun || !common->curlun->cdrom)
1954 goto unknown_cmnd;
1955 common->data_size_from_cmnd =
1956 get_unaligned_be16(&common->cmnd[7]);
1957 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1958 (7<<6) | (1<<1), 1,
1959 "READ TOC");
1960 if (reply == 0)
1961 reply = do_read_toc(common, bh);
1962 break;
1963
1964 case READ_FORMAT_CAPACITIES:
1965 common->data_size_from_cmnd =
1966 get_unaligned_be16(&common->cmnd[7]);
1967 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1968 (3<<7), 1,
1969 "READ FORMAT CAPACITIES");
1970 if (reply == 0)
1971 reply = do_read_format_capacities(common, bh);
1972 break;
1973
1974 case REQUEST_SENSE:
1975 common->data_size_from_cmnd = common->cmnd[4];
1976 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1977 (1<<4), 0,
1978 "REQUEST SENSE");
1979 if (reply == 0)
1980 reply = do_request_sense(common, bh);
1981 break;
1982
1983 case START_STOP:
1984 common->data_size_from_cmnd = 0;
1985 reply = check_command(common, 6, DATA_DIR_NONE,
1986 (1<<1) | (1<<4), 0,
1987 "START-STOP UNIT");
1988 if (reply == 0)
1989 reply = do_start_stop(common);
1990 break;
1991
1992 case SYNCHRONIZE_CACHE:
1993 common->data_size_from_cmnd = 0;
1994 reply = check_command(common, 10, DATA_DIR_NONE,
1995 (0xf<<2) | (3<<7), 1,
1996 "SYNCHRONIZE CACHE");
1997 if (reply == 0)
1998 reply = do_synchronize_cache(common);
1999 break;
2000
2001 case TEST_UNIT_READY:
2002 common->data_size_from_cmnd = 0;
2003 reply = check_command(common, 6, DATA_DIR_NONE,
2004 0, 1,
2005 "TEST UNIT READY");
2006 break;
2007
2008 /*
2009 * Although optional, this command is used by MS-Windows. We
2010 * support a minimal version: BytChk must be 0.
2011 */
2012 case VERIFY:
2013 common->data_size_from_cmnd = 0;
2014 reply = check_command(common, 10, DATA_DIR_NONE,
2015 (1<<1) | (0xf<<2) | (3<<7), 1,
2016 "VERIFY");
2017 if (reply == 0)
2018 reply = do_verify(common);
2019 break;
2020
2021 case WRITE_6:
2022 i = common->cmnd[4];
2023 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2024 reply = check_command_size_in_blocks(common, 6,
2025 DATA_DIR_FROM_HOST,
2026 (7<<1) | (1<<4), 1,
2027 "WRITE(6)");
2028 if (reply == 0)
2029 reply = do_write(common);
2030 break;
2031
2032 case WRITE_10:
2033 common->data_size_from_cmnd =
2034 get_unaligned_be16(&common->cmnd[7]);
2035 reply = check_command_size_in_blocks(common, 10,
2036 DATA_DIR_FROM_HOST,
2037 (1<<1) | (0xf<<2) | (3<<7), 1,
2038 "WRITE(10)");
2039 if (reply == 0)
2040 reply = do_write(common);
2041 break;
2042
2043 case WRITE_12:
2044 common->data_size_from_cmnd =
2045 get_unaligned_be32(&common->cmnd[6]);
2046 reply = check_command_size_in_blocks(common, 12,
2047 DATA_DIR_FROM_HOST,
2048 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2049 "WRITE(12)");
2050 if (reply == 0)
2051 reply = do_write(common);
2052 break;
2053
2054 /*
2055 * Some mandatory commands that we recognize but don't implement.
2056 * They don't mean much in this setting. It's left as an exercise
2057 * for anyone interested to implement RESERVE and RELEASE in terms
2058 * of Posix locks.
2059 */
2060 case FORMAT_UNIT:
2061 case RELEASE:
2062 case RESERVE:
2063 case SEND_DIAGNOSTIC:
2064 /* Fall through */
2065
2066 default:
2067unknown_cmnd:
2068 common->data_size_from_cmnd = 0;
2069 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2070 reply = check_command(common, common->cmnd_size,
2071 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2072 if (reply == 0) {
2073 common->curlun->sense_data = SS_INVALID_COMMAND;
2074 reply = -EINVAL;
2075 }
2076 break;
2077 }
2078 up_read(&common->filesem);
2079
2080 if (reply == -EINTR || signal_pending(current))
2081 return -EINTR;
2082
2083 /* Set up the single reply buffer for finish_reply() */
2084 if (reply == -EINVAL)
2085 reply = 0; /* Error reply length */
2086 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2087 reply = min((u32)reply, common->data_size_from_cmnd);
2088 bh->inreq->length = reply;
2089 bh->state = BUF_STATE_FULL;
2090 common->residue -= reply;
2091 } /* Otherwise it's already set */
2092
2093 return 0;
2094}
2095
2096
2097/*-------------------------------------------------------------------------*/
2098
2099static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2100{
2101 struct usb_request *req = bh->outreq;
2102 struct bulk_cb_wrap *cbw = req->buf;
2103 struct fsg_common *common = fsg->common;
2104
2105 /* Was this a real packet? Should it be ignored? */
2106 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2107 return -EINVAL;
2108
2109 /* Is the CBW valid? */
2110 if (req->actual != US_BULK_CB_WRAP_LEN ||
2111 cbw->Signature != cpu_to_le32(
2112 US_BULK_CB_SIGN)) {
2113 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2114 req->actual,
2115 le32_to_cpu(cbw->Signature));
2116
2117 /*
2118 * The Bulk-only spec says we MUST stall the IN endpoint
2119 * (6.6.1), so it's unavoidable. It also says we must
2120 * retain this state until the next reset, but there's
2121 * no way to tell the controller driver it should ignore
2122 * Clear-Feature(HALT) requests.
2123 *
2124 * We aren't required to halt the OUT endpoint; instead
2125 * we can simply accept and discard any data received
2126 * until the next reset.
2127 */
2128 wedge_bulk_in_endpoint(fsg);
2129 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2130 return -EINVAL;
2131 }
2132
2133 /* Is the CBW meaningful? */
2134 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2135 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2136 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2137 "cmdlen %u\n",
2138 cbw->Lun, cbw->Flags, cbw->Length);
2139
2140 /*
2141 * We can do anything we want here, so let's stall the
2142 * bulk pipes if we are allowed to.
2143 */
2144 if (common->can_stall) {
2145 fsg_set_halt(fsg, fsg->bulk_out);
2146 halt_bulk_in_endpoint(fsg);
2147 }
2148 return -EINVAL;
2149 }
2150
2151 /* Save the command for later */
2152 common->cmnd_size = cbw->Length;
2153 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2154 if (cbw->Flags & US_BULK_FLAG_IN)
2155 common->data_dir = DATA_DIR_TO_HOST;
2156 else
2157 common->data_dir = DATA_DIR_FROM_HOST;
2158 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2159 if (common->data_size == 0)
2160 common->data_dir = DATA_DIR_NONE;
2161 common->lun = cbw->Lun;
2162 if (common->lun < common->nluns)
2163 common->curlun = common->luns[common->lun];
2164 else
2165 common->curlun = NULL;
2166 common->tag = cbw->Tag;
2167 return 0;
2168}
2169
2170static int get_next_command(struct fsg_common *common)
2171{
2172 struct fsg_buffhd *bh;
2173 int rc = 0;
2174
2175 /* Wait for the next buffer to become available */
2176 bh = common->next_buffhd_to_fill;
2177 while (bh->state != BUF_STATE_EMPTY) {
2178 rc = sleep_thread(common, true);
2179 if (rc)
2180 return rc;
2181 }
2182
2183 /* Queue a request to read a Bulk-only CBW */
2184 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2185 if (!start_out_transfer(common, bh))
2186 /* Don't know what to do if common->fsg is NULL */
2187 return -EIO;
2188
2189 /*
2190 * We will drain the buffer in software, which means we
2191 * can reuse it for the next filling. No need to advance
2192 * next_buffhd_to_fill.
2193 */
2194
2195 /* Wait for the CBW to arrive */
2196 while (bh->state != BUF_STATE_FULL) {
2197 rc = sleep_thread(common, true);
2198 if (rc)
2199 return rc;
2200 }
2201 smp_rmb();
2202 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2203 bh->state = BUF_STATE_EMPTY;
2204
2205 return rc;
2206}
2207
2208
2209/*-------------------------------------------------------------------------*/
2210
2211static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2212 struct usb_request **preq)
2213{
2214 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2215 if (*preq)
2216 return 0;
2217 ERROR(common, "can't allocate request for %s\n", ep->name);
2218 return -ENOMEM;
2219}
2220
2221/* Reset interface setting and re-init endpoint state (toggle etc). */
2222static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2223{
2224 struct fsg_dev *fsg;
2225 int i, rc = 0;
2226
2227 if (common->running)
2228 DBG(common, "reset interface\n");
2229
2230reset:
2231 /* Deallocate the requests */
2232 if (common->fsg) {
2233 fsg = common->fsg;
2234
2235 for (i = 0; i < common->fsg_num_buffers; ++i) {
2236 struct fsg_buffhd *bh = &common->buffhds[i];
2237
2238 if (bh->inreq) {
2239 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2240 bh->inreq = NULL;
2241 }
2242 if (bh->outreq) {
2243 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2244 bh->outreq = NULL;
2245 }
2246 }
2247
2248 /* Disable the endpoints */
2249 if (fsg->bulk_in_enabled) {
2250 usb_ep_disable(fsg->bulk_in);
2251 fsg->bulk_in->driver_data = NULL;
2252 fsg->bulk_in_enabled = 0;
2253 }
2254 if (fsg->bulk_out_enabled) {
2255 usb_ep_disable(fsg->bulk_out);
2256 fsg->bulk_out->driver_data = NULL;
2257 fsg->bulk_out_enabled = 0;
2258 }
2259
2260 common->fsg = NULL;
2261 wake_up(&common->fsg_wait);
2262 }
2263
2264 common->running = 0;
2265 if (!new_fsg || rc)
2266 return rc;
2267
2268 common->fsg = new_fsg;
2269 fsg = common->fsg;
2270
2271 /* Enable the endpoints */
2272 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2273 if (rc)
2274 goto reset;
2275 rc = usb_ep_enable(fsg->bulk_in);
2276 if (rc)
2277 goto reset;
2278 fsg->bulk_in->driver_data = common;
2279 fsg->bulk_in_enabled = 1;
2280
2281 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2282 fsg->bulk_out);
2283 if (rc)
2284 goto reset;
2285 rc = usb_ep_enable(fsg->bulk_out);
2286 if (rc)
2287 goto reset;
2288 fsg->bulk_out->driver_data = common;
2289 fsg->bulk_out_enabled = 1;
2290 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2291 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2292
2293 /* Allocate the requests */
2294 for (i = 0; i < common->fsg_num_buffers; ++i) {
2295 struct fsg_buffhd *bh = &common->buffhds[i];
2296
2297 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2298 if (rc)
2299 goto reset;
2300 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2301 if (rc)
2302 goto reset;
2303 bh->inreq->buf = bh->outreq->buf = bh->buf;
2304 bh->inreq->context = bh->outreq->context = bh;
2305 bh->inreq->complete = bulk_in_complete;
2306 bh->outreq->complete = bulk_out_complete;
2307 }
2308
2309 common->running = 1;
2310 for (i = 0; i < common->nluns; ++i)
2311 if (common->luns[i])
2312 common->luns[i]->unit_attention_data =
2313 SS_RESET_OCCURRED;
2314 return rc;
2315}
2316
2317
2318/****************************** ALT CONFIGS ******************************/
2319
2320static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2321{
2322 struct fsg_dev *fsg = fsg_from_func(f);
2323 fsg->common->new_fsg = fsg;
2324 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2325 return USB_GADGET_DELAYED_STATUS;
2326}
2327
2328static void fsg_disable(struct usb_function *f)
2329{
2330 struct fsg_dev *fsg = fsg_from_func(f);
2331 fsg->common->new_fsg = NULL;
2332 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2333}
2334
2335
2336/*-------------------------------------------------------------------------*/
2337
2338static void handle_exception(struct fsg_common *common)
2339{
2340 siginfo_t info;
2341 int i;
2342 struct fsg_buffhd *bh;
2343 enum fsg_state old_state;
2344 struct fsg_lun *curlun;
2345 unsigned int exception_req_tag;
2346
2347 /*
2348 * Clear the existing signals. Anything but SIGUSR1 is converted
2349 * into a high-priority EXIT exception.
2350 */
2351 for (;;) {
2352 int sig =
2353 dequeue_signal_lock(current, ¤t->blocked, &info);
2354 if (!sig)
2355 break;
2356 if (sig != SIGUSR1) {
2357 if (common->state < FSG_STATE_EXIT)
2358 DBG(common, "Main thread exiting on signal\n");
2359 raise_exception(common, FSG_STATE_EXIT);
2360 }
2361 }
2362
2363 /* Cancel all the pending transfers */
2364 if (likely(common->fsg)) {
2365 for (i = 0; i < common->fsg_num_buffers; ++i) {
2366 bh = &common->buffhds[i];
2367 if (bh->inreq_busy)
2368 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2369 if (bh->outreq_busy)
2370 usb_ep_dequeue(common->fsg->bulk_out,
2371 bh->outreq);
2372 }
2373
2374 /* Wait until everything is idle */
2375 for (;;) {
2376 int num_active = 0;
2377 for (i = 0; i < common->fsg_num_buffers; ++i) {
2378 bh = &common->buffhds[i];
2379 num_active += bh->inreq_busy + bh->outreq_busy;
2380 }
2381 if (num_active == 0)
2382 break;
2383 if (sleep_thread(common, true))
2384 return;
2385 }
2386
2387 /* Clear out the controller's fifos */
2388 if (common->fsg->bulk_in_enabled)
2389 usb_ep_fifo_flush(common->fsg->bulk_in);
2390 if (common->fsg->bulk_out_enabled)
2391 usb_ep_fifo_flush(common->fsg->bulk_out);
2392 }
2393
2394 /*
2395 * Reset the I/O buffer states and pointers, the SCSI
2396 * state, and the exception. Then invoke the handler.
2397 */
2398 spin_lock_irq(&common->lock);
2399
2400 for (i = 0; i < common->fsg_num_buffers; ++i) {
2401 bh = &common->buffhds[i];
2402 bh->state = BUF_STATE_EMPTY;
2403 }
2404 common->next_buffhd_to_fill = &common->buffhds[0];
2405 common->next_buffhd_to_drain = &common->buffhds[0];
2406 exception_req_tag = common->exception_req_tag;
2407 old_state = common->state;
2408
2409 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2410 common->state = FSG_STATE_STATUS_PHASE;
2411 else {
2412 for (i = 0; i < common->nluns; ++i) {
2413 curlun = common->luns[i];
2414 if (!curlun)
2415 continue;
2416 curlun->prevent_medium_removal = 0;
2417 curlun->sense_data = SS_NO_SENSE;
2418 curlun->unit_attention_data = SS_NO_SENSE;
2419 curlun->sense_data_info = 0;
2420 curlun->info_valid = 0;
2421 }
2422 common->state = FSG_STATE_IDLE;
2423 }
2424 spin_unlock_irq(&common->lock);
2425
2426 /* Carry out any extra actions required for the exception */
2427 switch (old_state) {
2428 case FSG_STATE_ABORT_BULK_OUT:
2429 send_status(common);
2430 spin_lock_irq(&common->lock);
2431 if (common->state == FSG_STATE_STATUS_PHASE)
2432 common->state = FSG_STATE_IDLE;
2433 spin_unlock_irq(&common->lock);
2434 break;
2435
2436 case FSG_STATE_RESET:
2437 /*
2438 * In case we were forced against our will to halt a
2439 * bulk endpoint, clear the halt now. (The SuperH UDC
2440 * requires this.)
2441 */
2442 if (!fsg_is_set(common))
2443 break;
2444 if (test_and_clear_bit(IGNORE_BULK_OUT,
2445 &common->fsg->atomic_bitflags))
2446 usb_ep_clear_halt(common->fsg->bulk_in);
2447
2448 if (common->ep0_req_tag == exception_req_tag)
2449 ep0_queue(common); /* Complete the status stage */
2450
2451 /*
2452 * Technically this should go here, but it would only be
2453 * a waste of time. Ditto for the INTERFACE_CHANGE and
2454 * CONFIG_CHANGE cases.
2455 */
2456 /* for (i = 0; i < common->nluns; ++i) */
2457 /* if (common->luns[i]) */
2458 /* common->luns[i]->unit_attention_data = */
2459 /* SS_RESET_OCCURRED; */
2460 break;
2461
2462 case FSG_STATE_CONFIG_CHANGE:
2463 do_set_interface(common, common->new_fsg);
2464 if (common->new_fsg)
2465 usb_composite_setup_continue(common->cdev);
2466 break;
2467
2468 case FSG_STATE_EXIT:
2469 case FSG_STATE_TERMINATED:
2470 do_set_interface(common, NULL); /* Free resources */
2471 spin_lock_irq(&common->lock);
2472 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2473 spin_unlock_irq(&common->lock);
2474 break;
2475
2476 case FSG_STATE_INTERFACE_CHANGE:
2477 case FSG_STATE_DISCONNECT:
2478 case FSG_STATE_COMMAND_PHASE:
2479 case FSG_STATE_DATA_PHASE:
2480 case FSG_STATE_STATUS_PHASE:
2481 case FSG_STATE_IDLE:
2482 break;
2483 }
2484}
2485
2486
2487/*-------------------------------------------------------------------------*/
2488
2489static int fsg_main_thread(void *common_)
2490{
2491 struct fsg_common *common = common_;
2492
2493 /*
2494 * Allow the thread to be killed by a signal, but set the signal mask
2495 * to block everything but INT, TERM, KILL, and USR1.
2496 */
2497 allow_signal(SIGINT);
2498 allow_signal(SIGTERM);
2499 allow_signal(SIGKILL);
2500 allow_signal(SIGUSR1);
2501
2502 /* Allow the thread to be frozen */
2503 set_freezable();
2504
2505 /*
2506 * Arrange for userspace references to be interpreted as kernel
2507 * pointers. That way we can pass a kernel pointer to a routine
2508 * that expects a __user pointer and it will work okay.
2509 */
2510 set_fs(get_ds());
2511
2512 /* The main loop */
2513 while (common->state != FSG_STATE_TERMINATED) {
2514 if (exception_in_progress(common) || signal_pending(current)) {
2515 handle_exception(common);
2516 continue;
2517 }
2518
2519 if (!common->running) {
2520 sleep_thread(common, true);
2521 continue;
2522 }
2523
2524 if (get_next_command(common))
2525 continue;
2526
2527 spin_lock_irq(&common->lock);
2528 if (!exception_in_progress(common))
2529 common->state = FSG_STATE_DATA_PHASE;
2530 spin_unlock_irq(&common->lock);
2531
2532 if (do_scsi_command(common) || finish_reply(common))
2533 continue;
2534
2535 spin_lock_irq(&common->lock);
2536 if (!exception_in_progress(common))
2537 common->state = FSG_STATE_STATUS_PHASE;
2538 spin_unlock_irq(&common->lock);
2539
2540 if (send_status(common))
2541 continue;
2542
2543 spin_lock_irq(&common->lock);
2544 if (!exception_in_progress(common))
2545 common->state = FSG_STATE_IDLE;
2546 spin_unlock_irq(&common->lock);
2547 }
2548
2549 spin_lock_irq(&common->lock);
2550 common->thread_task = NULL;
2551 spin_unlock_irq(&common->lock);
2552
2553 if (!common->ops || !common->ops->thread_exits
2554 || common->ops->thread_exits(common) < 0) {
2555 struct fsg_lun **curlun_it = common->luns;
2556 unsigned i = common->nluns;
2557
2558 down_write(&common->filesem);
2559 for (; i--; ++curlun_it) {
2560 struct fsg_lun *curlun = *curlun_it;
2561 if (!curlun || !fsg_lun_is_open(curlun))
2562 continue;
2563
2564 fsg_lun_close(curlun);
2565 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2566 }
2567 up_write(&common->filesem);
2568 }
2569
2570 /* Let fsg_unbind() know the thread has exited */
2571 complete_and_exit(&common->thread_notifier, 0);
2572}
2573
2574
2575/*************************** DEVICE ATTRIBUTES ***************************/
2576
2577static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2578{
2579 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2580
2581 return fsg_show_ro(curlun, buf);
2582}
2583
2584static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2585 char *buf)
2586{
2587 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2588
2589 return fsg_show_nofua(curlun, buf);
2590}
2591
2592static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2593 char *buf)
2594{
2595 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2596 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2597
2598 return fsg_show_file(curlun, filesem, buf);
2599}
2600
2601static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2602 const char *buf, size_t count)
2603{
2604 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2605 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2606
2607 return fsg_store_ro(curlun, filesem, buf, count);
2608}
2609
2610static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2611 const char *buf, size_t count)
2612{
2613 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2614
2615 return fsg_store_nofua(curlun, buf, count);
2616}
2617
2618static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2619 const char *buf, size_t count)
2620{
2621 struct fsg_lun *curlun = fsg_lun_from_dev(dev);
2622 struct rw_semaphore *filesem = dev_get_drvdata(dev);
2623
2624 return fsg_store_file(curlun, filesem, buf, count);
2625}
2626
2627static DEVICE_ATTR_RW(ro);
2628static DEVICE_ATTR_RW(nofua);
2629static DEVICE_ATTR_RW(file);
2630
2631static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro);
2632static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file);
2633
2634
2635/****************************** FSG COMMON ******************************/
2636
2637static void fsg_common_release(struct kref *ref);
2638
2639static void fsg_lun_release(struct device *dev)
2640{
2641 /* Nothing needs to be done */
2642}
2643
2644void fsg_common_get(struct fsg_common *common)
2645{
2646 kref_get(&common->ref);
2647}
2648EXPORT_SYMBOL_GPL(fsg_common_get);
2649
2650void fsg_common_put(struct fsg_common *common)
2651{
2652 kref_put(&common->ref, fsg_common_release);
2653}
2654EXPORT_SYMBOL_GPL(fsg_common_put);
2655
2656/* check if fsg_num_buffers is within a valid range */
2657static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
2658{
2659 if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
2660 return 0;
2661 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
2662 fsg_num_buffers, 2, 4);
2663 return -EINVAL;
2664}
2665
2666static struct fsg_common *fsg_common_setup(struct fsg_common *common)
2667{
2668 if (!common) {
2669 common = kzalloc(sizeof(*common), GFP_KERNEL);
2670 if (!common)
2671 return ERR_PTR(-ENOMEM);
2672 common->free_storage_on_release = 1;
2673 } else {
2674 common->free_storage_on_release = 0;
2675 }
2676 init_rwsem(&common->filesem);
2677 spin_lock_init(&common->lock);
2678 kref_init(&common->ref);
2679 init_completion(&common->thread_notifier);
2680 init_waitqueue_head(&common->fsg_wait);
2681 common->state = FSG_STATE_TERMINATED;
2682
2683 return common;
2684}
2685
2686void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2687{
2688 common->sysfs = sysfs;
2689}
2690EXPORT_SYMBOL_GPL(fsg_common_set_sysfs);
2691
2692static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2693{
2694 if (buffhds) {
2695 struct fsg_buffhd *bh = buffhds;
2696 while (n--) {
2697 kfree(bh->buf);
2698 ++bh;
2699 }
2700 kfree(buffhds);
2701 }
2702}
2703
2704int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2705{
2706 struct fsg_buffhd *bh, *buffhds;
2707 int i, rc;
2708
2709 rc = fsg_num_buffers_validate(n);
2710 if (rc != 0)
2711 return rc;
2712
2713 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2714 if (!buffhds)
2715 return -ENOMEM;
2716
2717 /* Data buffers cyclic list */
2718 bh = buffhds;
2719 i = n;
2720 goto buffhds_first_it;
2721 do {
2722 bh->next = bh + 1;
2723 ++bh;
2724buffhds_first_it:
2725 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2726 if (unlikely(!bh->buf))
2727 goto error_release;
2728 } while (--i);
2729 bh->next = buffhds;
2730
2731 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2732 common->fsg_num_buffers = n;
2733 common->buffhds = buffhds;
2734
2735 return 0;
2736
2737error_release:
2738 /*
2739 * "buf"s pointed to by heads after n - i are NULL
2740 * so releasing them won't hurt
2741 */
2742 _fsg_common_free_buffers(buffhds, n);
2743
2744 return -ENOMEM;
2745}
2746EXPORT_SYMBOL_GPL(fsg_common_set_num_buffers);
2747
2748static inline void fsg_common_remove_sysfs(struct fsg_lun *lun)
2749{
2750 device_remove_file(&lun->dev, &dev_attr_nofua);
2751 /*
2752 * device_remove_file() =>
2753 *
2754 * here the attr (e.g. dev_attr_ro) is only used to be passed to:
2755 *
2756 * sysfs_remove_file() =>
2757 *
2758 * here e.g. both dev_attr_ro_cdrom and dev_attr_ro are in
2759 * the same namespace and
2760 * from here only attr->name is passed to:
2761 *
2762 * sysfs_hash_and_remove()
2763 *
2764 * attr->name is the same for dev_attr_ro_cdrom and
2765 * dev_attr_ro
2766 * attr->name is the same for dev_attr_file and
2767 * dev_attr_file_nonremovable
2768 *
2769 * so we don't differentiate between removing e.g. dev_attr_ro_cdrom
2770 * and dev_attr_ro
2771 */
2772 device_remove_file(&lun->dev, &dev_attr_ro);
2773 device_remove_file(&lun->dev, &dev_attr_file);
2774}
2775
2776void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs)
2777{
2778 if (sysfs) {
2779 fsg_common_remove_sysfs(lun);
2780 device_unregister(&lun->dev);
2781 }
2782 fsg_lun_close(lun);
2783 kfree(lun);
2784}
2785EXPORT_SYMBOL_GPL(fsg_common_remove_lun);
2786
2787static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2788{
2789 int i;
2790
2791 for (i = 0; i < n; ++i)
2792 if (common->luns[i]) {
2793 fsg_common_remove_lun(common->luns[i], common->sysfs);
2794 common->luns[i] = NULL;
2795 }
2796}
2797EXPORT_SYMBOL_GPL(fsg_common_remove_luns);
2798
2799void fsg_common_remove_luns(struct fsg_common *common)
2800{
2801 _fsg_common_remove_luns(common, common->nluns);
2802}
2803
2804void fsg_common_free_luns(struct fsg_common *common)
2805{
2806 fsg_common_remove_luns(common);
2807 kfree(common->luns);
2808 common->luns = NULL;
2809}
2810EXPORT_SYMBOL_GPL(fsg_common_free_luns);
2811
2812int fsg_common_set_nluns(struct fsg_common *common, int nluns)
2813{
2814 struct fsg_lun **curlun;
2815
2816 /* Find out how many LUNs there should be */
2817 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2818 pr_err("invalid number of LUNs: %u\n", nluns);
2819 return -EINVAL;
2820 }
2821
2822 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2823 if (unlikely(!curlun))
2824 return -ENOMEM;
2825
2826 if (common->luns)
2827 fsg_common_free_luns(common);
2828
2829 common->luns = curlun;
2830 common->nluns = nluns;
2831
2832 pr_info("Number of LUNs=%d\n", common->nluns);
2833
2834 return 0;
2835}
2836EXPORT_SYMBOL_GPL(fsg_common_set_nluns);
2837
2838void fsg_common_set_ops(struct fsg_common *common,
2839 const struct fsg_operations *ops)
2840{
2841 common->ops = ops;
2842}
2843EXPORT_SYMBOL_GPL(fsg_common_set_ops);
2844
2845void fsg_common_free_buffers(struct fsg_common *common)
2846{
2847 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2848 common->buffhds = NULL;
2849}
2850EXPORT_SYMBOL_GPL(fsg_common_free_buffers);
2851
2852int fsg_common_set_cdev(struct fsg_common *common,
2853 struct usb_composite_dev *cdev, bool can_stall)
2854{
2855 struct usb_string *us;
2856
2857 common->gadget = cdev->gadget;
2858 common->ep0 = cdev->gadget->ep0;
2859 common->ep0req = cdev->req;
2860 common->cdev = cdev;
2861
2862 us = usb_gstrings_attach(cdev, fsg_strings_array,
2863 ARRAY_SIZE(fsg_strings));
2864 if (IS_ERR(us))
2865 return PTR_ERR(us);
2866
2867 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2868
2869 /*
2870 * Some peripheral controllers are known not to be able to
2871 * halt bulk endpoints correctly. If one of them is present,
2872 * disable stalls.
2873 */
2874 common->can_stall = can_stall && !(gadget_is_at91(common->gadget));
2875
2876 return 0;
2877}
2878EXPORT_SYMBOL_GPL(fsg_common_set_cdev);
2879
2880static inline int fsg_common_add_sysfs(struct fsg_common *common,
2881 struct fsg_lun *lun)
2882{
2883 int rc;
2884
2885 rc = device_register(&lun->dev);
2886 if (rc) {
2887 put_device(&lun->dev);
2888 return rc;
2889 }
2890
2891 rc = device_create_file(&lun->dev,
2892 lun->cdrom
2893 ? &dev_attr_ro_cdrom
2894 : &dev_attr_ro);
2895 if (rc)
2896 goto error;
2897 rc = device_create_file(&lun->dev,
2898 lun->removable
2899 ? &dev_attr_file
2900 : &dev_attr_file_nonremovable);
2901 if (rc)
2902 goto error;
2903 rc = device_create_file(&lun->dev, &dev_attr_nofua);
2904 if (rc)
2905 goto error;
2906
2907 return 0;
2908
2909error:
2910 /* removing nonexistent files is a no-op */
2911 fsg_common_remove_sysfs(lun);
2912 device_unregister(&lun->dev);
2913 return rc;
2914}
2915
2916int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
2917 unsigned int id, const char *name,
2918 const char **name_pfx)
2919{
2920 struct fsg_lun *lun;
2921 char *pathbuf, *p;
2922 int rc = -ENOMEM;
2923
2924 if (!common->nluns || !common->luns)
2925 return -ENODEV;
2926
2927 if (common->luns[id])
2928 return -EBUSY;
2929
2930 if (!cfg->filename && !cfg->removable) {
2931 pr_err("no file given for LUN%d\n", id);
2932 return -EINVAL;
2933 }
2934
2935 lun = kzalloc(sizeof(*lun), GFP_KERNEL);
2936 if (!lun)
2937 return -ENOMEM;
2938
2939 lun->name_pfx = name_pfx;
2940
2941 lun->cdrom = !!cfg->cdrom;
2942 lun->ro = cfg->cdrom || cfg->ro;
2943 lun->initially_ro = lun->ro;
2944 lun->removable = !!cfg->removable;
2945
2946 if (!common->sysfs) {
2947 /* we DON'T own the name!*/
2948 lun->name = name;
2949 } else {
2950 lun->dev.release = fsg_lun_release;
2951 lun->dev.parent = &common->gadget->dev;
2952 dev_set_drvdata(&lun->dev, &common->filesem);
2953 dev_set_name(&lun->dev, "%s", name);
2954 lun->name = dev_name(&lun->dev);
2955
2956 rc = fsg_common_add_sysfs(common, lun);
2957 if (rc) {
2958 pr_info("failed to register LUN%d: %d\n", id, rc);
2959 goto error_sysfs;
2960 }
2961 }
2962
2963 common->luns[id] = lun;
2964
2965 if (cfg->filename) {
2966 rc = fsg_lun_open(lun, cfg->filename);
2967 if (rc)
2968 goto error_lun;
2969 }
2970
2971 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2972 p = "(no medium)";
2973 if (fsg_lun_is_open(lun)) {
2974 p = "(error)";
2975 if (pathbuf) {
2976 p = d_path(&lun->filp->f_path, pathbuf, PATH_MAX);
2977 if (IS_ERR(p))
2978 p = "(error)";
2979 }
2980 }
2981 pr_info("LUN: %s%s%sfile: %s\n",
2982 lun->removable ? "removable " : "",
2983 lun->ro ? "read only " : "",
2984 lun->cdrom ? "CD-ROM " : "",
2985 p);
2986 kfree(pathbuf);
2987
2988 return 0;
2989
2990error_lun:
2991 if (common->sysfs) {
2992 fsg_common_remove_sysfs(lun);
2993 device_unregister(&lun->dev);
2994 }
2995 fsg_lun_close(lun);
2996 common->luns[id] = NULL;
2997error_sysfs:
2998 kfree(lun);
2999 return rc;
3000}
3001EXPORT_SYMBOL_GPL(fsg_common_create_lun);
3002
3003int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
3004{
3005 char buf[8]; /* enough for 100000000 different numbers, decimal */
3006 int i, rc;
3007
3008 for (i = 0; i < common->nluns; ++i) {
3009 snprintf(buf, sizeof(buf), "lun%d", i);
3010 rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
3011 if (rc)
3012 goto fail;
3013 }
3014
3015 pr_info("Number of LUNs=%d\n", common->nluns);
3016
3017 return 0;
3018
3019fail:
3020 _fsg_common_remove_luns(common, i);
3021 return rc;
3022}
3023EXPORT_SYMBOL_GPL(fsg_common_create_luns);
3024
3025void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
3026 const char *pn)
3027{
3028 int i;
3029
3030 /* Prepare inquiryString */
3031 i = get_default_bcdDevice();
3032 snprintf(common->inquiry_string, sizeof(common->inquiry_string),
3033 "%-8s%-16s%04x", vn ?: "Linux",
3034 /* Assume product name dependent on the first LUN */
3035 pn ?: ((*common->luns)->cdrom
3036 ? "File-CD Gadget"
3037 : "File-Stor Gadget"),
3038 i);
3039}
3040EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
3041
3042int fsg_common_run_thread(struct fsg_common *common)
3043{
3044 common->state = FSG_STATE_IDLE;
3045 /* Tell the thread to start working */
3046 common->thread_task =
3047 kthread_create(fsg_main_thread, common, "file-storage");
3048 if (IS_ERR(common->thread_task)) {
3049 common->state = FSG_STATE_TERMINATED;
3050 return PTR_ERR(common->thread_task);
3051 }
3052
3053 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
3054
3055 wake_up_process(common->thread_task);
3056
3057 return 0;
3058}
3059EXPORT_SYMBOL_GPL(fsg_common_run_thread);
3060
3061static void fsg_common_release(struct kref *ref)
3062{
3063 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
3064
3065 /* If the thread isn't already dead, tell it to exit now */
3066 if (common->state != FSG_STATE_TERMINATED) {
3067 raise_exception(common, FSG_STATE_EXIT);
3068 wait_for_completion(&common->thread_notifier);
3069 }
3070
3071 if (likely(common->luns)) {
3072 struct fsg_lun **lun_it = common->luns;
3073 unsigned i = common->nluns;
3074
3075 /* In error recovery common->nluns may be zero. */
3076 for (; i; --i, ++lun_it) {
3077 struct fsg_lun *lun = *lun_it;
3078 if (!lun)
3079 continue;
3080 if (common->sysfs)
3081 fsg_common_remove_sysfs(lun);
3082 fsg_lun_close(lun);
3083 if (common->sysfs)
3084 device_unregister(&lun->dev);
3085 kfree(lun);
3086 }
3087
3088 kfree(common->luns);
3089 }
3090
3091 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
3092 if (common->free_storage_on_release)
3093 kfree(common);
3094}
3095
3096
3097/*-------------------------------------------------------------------------*/
3098
3099static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3100{
3101 struct fsg_dev *fsg = fsg_from_func(f);
3102 struct usb_gadget *gadget = c->cdev->gadget;
3103 int i;
3104 struct usb_ep *ep;
3105 unsigned max_burst;
3106 int ret;
3107 struct fsg_opts *opts;
3108
3109 opts = fsg_opts_from_func_inst(f->fi);
3110 if (!opts->no_configfs) {
3111 ret = fsg_common_set_cdev(fsg->common, c->cdev,
3112 fsg->common->can_stall);
3113 if (ret)
3114 return ret;
3115 fsg_common_set_inquiry_string(fsg->common, NULL, NULL);
3116 ret = fsg_common_run_thread(fsg->common);
3117 if (ret)
3118 return ret;
3119 }
3120
3121 fsg->gadget = gadget;
3122
3123 /* New interface */
3124 i = usb_interface_id(c, f);
3125 if (i < 0)
3126 return i;
3127 fsg_intf_desc.bInterfaceNumber = i;
3128 fsg->interface_number = i;
3129
3130 /* Find all the endpoints we will use */
3131 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3132 if (!ep)
3133 goto autoconf_fail;
3134 ep->driver_data = fsg->common; /* claim the endpoint */
3135 fsg->bulk_in = ep;
3136
3137 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3138 if (!ep)
3139 goto autoconf_fail;
3140 ep->driver_data = fsg->common; /* claim the endpoint */
3141 fsg->bulk_out = ep;
3142
3143 /* Assume endpoint addresses are the same for both speeds */
3144 fsg_hs_bulk_in_desc.bEndpointAddress =
3145 fsg_fs_bulk_in_desc.bEndpointAddress;
3146 fsg_hs_bulk_out_desc.bEndpointAddress =
3147 fsg_fs_bulk_out_desc.bEndpointAddress;
3148
3149 /* Calculate bMaxBurst, we know packet size is 1024 */
3150 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3151
3152 fsg_ss_bulk_in_desc.bEndpointAddress =
3153 fsg_fs_bulk_in_desc.bEndpointAddress;
3154 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3155
3156 fsg_ss_bulk_out_desc.bEndpointAddress =
3157 fsg_fs_bulk_out_desc.bEndpointAddress;
3158 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3159
3160 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3161 fsg_ss_function);
3162 if (ret)
3163 goto autoconf_fail;
3164
3165 return 0;
3166
3167autoconf_fail:
3168 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3169 return -ENOTSUPP;
3170}
3171
3172/****************************** ALLOCATE FUNCTION *************************/
3173
3174static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3175{
3176 struct fsg_dev *fsg = fsg_from_func(f);
3177 struct fsg_common *common = fsg->common;
3178
3179 DBG(fsg, "unbind\n");
3180 if (fsg->common->fsg == fsg) {
3181 fsg->common->new_fsg = NULL;
3182 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
3183 /* FIXME: make interruptible or killable somehow? */
3184 wait_event(common->fsg_wait, common->fsg != fsg);
3185 }
3186
3187 usb_free_all_descriptors(&fsg->function);
3188}
3189
3190static inline struct fsg_lun_opts *to_fsg_lun_opts(struct config_item *item)
3191{
3192 return container_of(to_config_group(item), struct fsg_lun_opts, group);
3193}
3194
3195static inline struct fsg_opts *to_fsg_opts(struct config_item *item)
3196{
3197 return container_of(to_config_group(item), struct fsg_opts,
3198 func_inst.group);
3199}
3200
3201CONFIGFS_ATTR_STRUCT(fsg_lun_opts);
3202CONFIGFS_ATTR_OPS(fsg_lun_opts);
3203
3204static void fsg_lun_attr_release(struct config_item *item)
3205{
3206 struct fsg_lun_opts *lun_opts;
3207
3208 lun_opts = to_fsg_lun_opts(item);
3209 kfree(lun_opts);
3210}
3211
3212static struct configfs_item_operations fsg_lun_item_ops = {
3213 .release = fsg_lun_attr_release,
3214 .show_attribute = fsg_lun_opts_attr_show,
3215 .store_attribute = fsg_lun_opts_attr_store,
3216};
3217
3218static ssize_t fsg_lun_opts_file_show(struct fsg_lun_opts *opts, char *page)
3219{
3220 struct fsg_opts *fsg_opts;
3221
3222 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3223
3224 return fsg_show_file(opts->lun, &fsg_opts->common->filesem, page);
3225}
3226
3227static ssize_t fsg_lun_opts_file_store(struct fsg_lun_opts *opts,
3228 const char *page, size_t len)
3229{
3230 struct fsg_opts *fsg_opts;
3231
3232 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3233
3234 return fsg_store_file(opts->lun, &fsg_opts->common->filesem, page, len);
3235}
3236
3237static struct fsg_lun_opts_attribute fsg_lun_opts_file =
3238 __CONFIGFS_ATTR(file, S_IRUGO | S_IWUSR, fsg_lun_opts_file_show,
3239 fsg_lun_opts_file_store);
3240
3241static ssize_t fsg_lun_opts_ro_show(struct fsg_lun_opts *opts, char *page)
3242{
3243 return fsg_show_ro(opts->lun, page);
3244}
3245
3246static ssize_t fsg_lun_opts_ro_store(struct fsg_lun_opts *opts,
3247 const char *page, size_t len)
3248{
3249 struct fsg_opts *fsg_opts;
3250
3251 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3252
3253 return fsg_store_ro(opts->lun, &fsg_opts->common->filesem, page, len);
3254}
3255
3256static struct fsg_lun_opts_attribute fsg_lun_opts_ro =
3257 __CONFIGFS_ATTR(ro, S_IRUGO | S_IWUSR, fsg_lun_opts_ro_show,
3258 fsg_lun_opts_ro_store);
3259
3260static ssize_t fsg_lun_opts_removable_show(struct fsg_lun_opts *opts,
3261 char *page)
3262{
3263 return fsg_show_removable(opts->lun, page);
3264}
3265
3266static ssize_t fsg_lun_opts_removable_store(struct fsg_lun_opts *opts,
3267 const char *page, size_t len)
3268{
3269 return fsg_store_removable(opts->lun, page, len);
3270}
3271
3272static struct fsg_lun_opts_attribute fsg_lun_opts_removable =
3273 __CONFIGFS_ATTR(removable, S_IRUGO | S_IWUSR,
3274 fsg_lun_opts_removable_show,
3275 fsg_lun_opts_removable_store);
3276
3277static ssize_t fsg_lun_opts_cdrom_show(struct fsg_lun_opts *opts, char *page)
3278{
3279 return fsg_show_cdrom(opts->lun, page);
3280}
3281
3282static ssize_t fsg_lun_opts_cdrom_store(struct fsg_lun_opts *opts,
3283 const char *page, size_t len)
3284{
3285 struct fsg_opts *fsg_opts;
3286
3287 fsg_opts = to_fsg_opts(opts->group.cg_item.ci_parent);
3288
3289 return fsg_store_cdrom(opts->lun, &fsg_opts->common->filesem, page,
3290 len);
3291}
3292
3293static struct fsg_lun_opts_attribute fsg_lun_opts_cdrom =
3294 __CONFIGFS_ATTR(cdrom, S_IRUGO | S_IWUSR, fsg_lun_opts_cdrom_show,
3295 fsg_lun_opts_cdrom_store);
3296
3297static ssize_t fsg_lun_opts_nofua_show(struct fsg_lun_opts *opts, char *page)
3298{
3299 return fsg_show_nofua(opts->lun, page);
3300}
3301
3302static ssize_t fsg_lun_opts_nofua_store(struct fsg_lun_opts *opts,
3303 const char *page, size_t len)
3304{
3305 return fsg_store_nofua(opts->lun, page, len);
3306}
3307
3308static struct fsg_lun_opts_attribute fsg_lun_opts_nofua =
3309 __CONFIGFS_ATTR(nofua, S_IRUGO | S_IWUSR, fsg_lun_opts_nofua_show,
3310 fsg_lun_opts_nofua_store);
3311
3312static struct configfs_attribute *fsg_lun_attrs[] = {
3313 &fsg_lun_opts_file.attr,
3314 &fsg_lun_opts_ro.attr,
3315 &fsg_lun_opts_removable.attr,
3316 &fsg_lun_opts_cdrom.attr,
3317 &fsg_lun_opts_nofua.attr,
3318 NULL,
3319};
3320
3321static struct config_item_type fsg_lun_type = {
3322 .ct_item_ops = &fsg_lun_item_ops,
3323 .ct_attrs = fsg_lun_attrs,
3324 .ct_owner = THIS_MODULE,
3325};
3326
3327static struct config_group *fsg_lun_make(struct config_group *group,
3328 const char *name)
3329{
3330 struct fsg_lun_opts *opts;
3331 struct fsg_opts *fsg_opts;
3332 struct fsg_lun_config config;
3333 char *num_str;
3334 u8 num;
3335 int ret;
3336
3337 num_str = strchr(name, '.');
3338 if (!num_str) {
3339 pr_err("Unable to locate . in LUN.NUMBER\n");
3340 return ERR_PTR(-EINVAL);
3341 }
3342 num_str++;
3343
3344 ret = kstrtou8(num_str, 0, &num);
3345 if (ret)
3346 return ERR_PTR(ret);
3347
3348 fsg_opts = to_fsg_opts(&group->cg_item);
3349 if (num >= FSG_MAX_LUNS)
3350 return ERR_PTR(-ERANGE);
3351
3352 mutex_lock(&fsg_opts->lock);
3353 if (fsg_opts->refcnt || fsg_opts->common->luns[num]) {
3354 ret = -EBUSY;
3355 goto out;
3356 }
3357
3358 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3359 if (!opts) {
3360 ret = -ENOMEM;
3361 goto out;
3362 }
3363
3364 memset(&config, 0, sizeof(config));
3365 config.removable = true;
3366
3367 ret = fsg_common_create_lun(fsg_opts->common, &config, num, name,
3368 (const char **)&group->cg_item.ci_name);
3369 if (ret) {
3370 kfree(opts);
3371 goto out;
3372 }
3373 opts->lun = fsg_opts->common->luns[num];
3374 opts->lun_id = num;
3375 mutex_unlock(&fsg_opts->lock);
3376
3377 config_group_init_type_name(&opts->group, name, &fsg_lun_type);
3378
3379 return &opts->group;
3380out:
3381 mutex_unlock(&fsg_opts->lock);
3382 return ERR_PTR(ret);
3383}
3384
3385static void fsg_lun_drop(struct config_group *group, struct config_item *item)
3386{
3387 struct fsg_lun_opts *lun_opts;
3388 struct fsg_opts *fsg_opts;
3389
3390 lun_opts = to_fsg_lun_opts(item);
3391 fsg_opts = to_fsg_opts(&group->cg_item);
3392
3393 mutex_lock(&fsg_opts->lock);
3394 if (fsg_opts->refcnt) {
3395 struct config_item *gadget;
3396
3397 gadget = group->cg_item.ci_parent->ci_parent;
3398 unregister_gadget_item(gadget);
3399 }
3400
3401 fsg_common_remove_lun(lun_opts->lun, fsg_opts->common->sysfs);
3402 fsg_opts->common->luns[lun_opts->lun_id] = NULL;
3403 lun_opts->lun_id = 0;
3404 mutex_unlock(&fsg_opts->lock);
3405
3406 config_item_put(item);
3407}
3408
3409CONFIGFS_ATTR_STRUCT(fsg_opts);
3410CONFIGFS_ATTR_OPS(fsg_opts);
3411
3412static void fsg_attr_release(struct config_item *item)
3413{
3414 struct fsg_opts *opts = to_fsg_opts(item);
3415
3416 usb_put_function_instance(&opts->func_inst);
3417}
3418
3419static struct configfs_item_operations fsg_item_ops = {
3420 .release = fsg_attr_release,
3421 .show_attribute = fsg_opts_attr_show,
3422 .store_attribute = fsg_opts_attr_store,
3423};
3424
3425static ssize_t fsg_opts_stall_show(struct fsg_opts *opts, char *page)
3426{
3427 int result;
3428
3429 mutex_lock(&opts->lock);
3430 result = sprintf(page, "%d", opts->common->can_stall);
3431 mutex_unlock(&opts->lock);
3432
3433 return result;
3434}
3435
3436static ssize_t fsg_opts_stall_store(struct fsg_opts *opts, const char *page,
3437 size_t len)
3438{
3439 int ret;
3440 bool stall;
3441
3442 mutex_lock(&opts->lock);
3443
3444 if (opts->refcnt) {
3445 mutex_unlock(&opts->lock);
3446 return -EBUSY;
3447 }
3448
3449 ret = strtobool(page, &stall);
3450 if (!ret) {
3451 opts->common->can_stall = stall;
3452 ret = len;
3453 }
3454
3455 mutex_unlock(&opts->lock);
3456
3457 return ret;
3458}
3459
3460static struct fsg_opts_attribute fsg_opts_stall =
3461 __CONFIGFS_ATTR(stall, S_IRUGO | S_IWUSR, fsg_opts_stall_show,
3462 fsg_opts_stall_store);
3463
3464#ifdef CONFIG_USB_GADGET_DEBUG_FILES
3465static ssize_t fsg_opts_num_buffers_show(struct fsg_opts *opts, char *page)
3466{
3467 int result;
3468
3469 mutex_lock(&opts->lock);
3470 result = sprintf(page, "%d", opts->common->fsg_num_buffers);
3471 mutex_unlock(&opts->lock);
3472
3473 return result;
3474}
3475
3476static ssize_t fsg_opts_num_buffers_store(struct fsg_opts *opts,
3477 const char *page, size_t len)
3478{
3479 int ret;
3480 u8 num;
3481
3482 mutex_lock(&opts->lock);
3483 if (opts->refcnt) {
3484 ret = -EBUSY;
3485 goto end;
3486 }
3487 ret = kstrtou8(page, 0, &num);
3488 if (ret)
3489 goto end;
3490
3491 ret = fsg_num_buffers_validate(num);
3492 if (ret)
3493 goto end;
3494
3495 fsg_common_set_num_buffers(opts->common, num);
3496 ret = len;
3497
3498end:
3499 mutex_unlock(&opts->lock);
3500 return ret;
3501}
3502
3503static struct fsg_opts_attribute fsg_opts_num_buffers =
3504 __CONFIGFS_ATTR(num_buffers, S_IRUGO | S_IWUSR,
3505 fsg_opts_num_buffers_show,
3506 fsg_opts_num_buffers_store);
3507
3508#endif
3509
3510static struct configfs_attribute *fsg_attrs[] = {
3511 &fsg_opts_stall.attr,
3512#ifdef CONFIG_USB_GADGET_DEBUG_FILES
3513 &fsg_opts_num_buffers.attr,
3514#endif
3515 NULL,
3516};
3517
3518static struct configfs_group_operations fsg_group_ops = {
3519 .make_group = fsg_lun_make,
3520 .drop_item = fsg_lun_drop,
3521};
3522
3523static struct config_item_type fsg_func_type = {
3524 .ct_item_ops = &fsg_item_ops,
3525 .ct_group_ops = &fsg_group_ops,
3526 .ct_attrs = fsg_attrs,
3527 .ct_owner = THIS_MODULE,
3528};
3529
3530static void fsg_free_inst(struct usb_function_instance *fi)
3531{
3532 struct fsg_opts *opts;
3533
3534 opts = fsg_opts_from_func_inst(fi);
3535 fsg_common_put(opts->common);
3536 kfree(opts);
3537}
3538
3539static struct usb_function_instance *fsg_alloc_inst(void)
3540{
3541 struct fsg_opts *opts;
3542 struct fsg_lun_config config;
3543 int rc;
3544
3545 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3546 if (!opts)
3547 return ERR_PTR(-ENOMEM);
3548 mutex_init(&opts->lock);
3549 opts->func_inst.free_func_inst = fsg_free_inst;
3550 opts->common = fsg_common_setup(opts->common);
3551 if (IS_ERR(opts->common)) {
3552 rc = PTR_ERR(opts->common);
3553 goto release_opts;
3554 }
3555 rc = fsg_common_set_nluns(opts->common, FSG_MAX_LUNS);
3556 if (rc)
3557 goto release_opts;
3558
3559 rc = fsg_common_set_num_buffers(opts->common,
3560 CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
3561 if (rc)
3562 goto release_luns;
3563
3564 pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3565
3566 memset(&config, 0, sizeof(config));
3567 config.removable = true;
3568 rc = fsg_common_create_lun(opts->common, &config, 0, "lun.0",
3569 (const char **)&opts->func_inst.group.cg_item.ci_name);
3570 opts->lun0.lun = opts->common->luns[0];
3571 opts->lun0.lun_id = 0;
3572 config_group_init_type_name(&opts->lun0.group, "lun.0", &fsg_lun_type);
3573 opts->default_groups[0] = &opts->lun0.group;
3574 opts->func_inst.group.default_groups = opts->default_groups;
3575
3576 config_group_init_type_name(&opts->func_inst.group, "", &fsg_func_type);
3577
3578 return &opts->func_inst;
3579
3580release_luns:
3581 kfree(opts->common->luns);
3582release_opts:
3583 kfree(opts);
3584 return ERR_PTR(rc);
3585}
3586
3587static void fsg_free(struct usb_function *f)
3588{
3589 struct fsg_dev *fsg;
3590 struct fsg_opts *opts;
3591
3592 fsg = container_of(f, struct fsg_dev, function);
3593 opts = container_of(f->fi, struct fsg_opts, func_inst);
3594
3595 mutex_lock(&opts->lock);
3596 opts->refcnt--;
3597 mutex_unlock(&opts->lock);
3598
3599 kfree(fsg);
3600}
3601
3602static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
3603{
3604 struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
3605 struct fsg_common *common = opts->common;
3606 struct fsg_dev *fsg;
3607
3608 fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
3609 if (unlikely(!fsg))
3610 return ERR_PTR(-ENOMEM);
3611
3612 mutex_lock(&opts->lock);
3613 opts->refcnt++;
3614 mutex_unlock(&opts->lock);
3615 fsg->function.name = FSG_DRIVER_DESC;
3616 fsg->function.bind = fsg_bind;
3617 fsg->function.unbind = fsg_unbind;
3618 fsg->function.setup = fsg_setup;
3619 fsg->function.set_alt = fsg_set_alt;
3620 fsg->function.disable = fsg_disable;
3621 fsg->function.free_func = fsg_free;
3622
3623 fsg->common = common;
3624
3625 return &fsg->function;
3626}
3627
3628DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
3629MODULE_LICENSE("GPL");
3630MODULE_AUTHOR("Michal Nazarewicz");
3631
3632/************************* Module parameters *************************/
3633
3634
3635void fsg_config_from_params(struct fsg_config *cfg,
3636 const struct fsg_module_parameters *params,
3637 unsigned int fsg_num_buffers)
3638{
3639 struct fsg_lun_config *lun;
3640 unsigned i;
3641
3642 /* Configure LUNs */
3643 cfg->nluns =
3644 min(params->luns ?: (params->file_count ?: 1u),
3645 (unsigned)FSG_MAX_LUNS);
3646 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3647 lun->ro = !!params->ro[i];
3648 lun->cdrom = !!params->cdrom[i];
3649 lun->removable = !!params->removable[i];
3650 lun->filename =
3651 params->file_count > i && params->file[i][0]
3652 ? params->file[i]
3653 : NULL;
3654 }
3655
3656 /* Let MSF use defaults */
3657 cfg->vendor_name = NULL;
3658 cfg->product_name = NULL;
3659
3660 cfg->ops = NULL;
3661 cfg->private_data = NULL;
3662
3663 /* Finalise */
3664 cfg->can_stall = params->stall;
3665 cfg->fsg_num_buffers = fsg_num_buffers;
3666}
3667EXPORT_SYMBOL_GPL(fsg_config_from_params);
3668