1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
2 /*
3 * f_mass_storage.c -- Mass Storage USB Composite Function
4 *
5 * Copyright (C) 2003-2008 Alan Stern
6 * Copyright (C) 2009 Samsung Electronics
7 * Author: Michal Nazarewicz <m.nazarewicz@samsung.com>
8 * All rights reserved.
9 */
10
11 /*
12 * The Mass Storage Function acts as a USB Mass Storage device,
13 * appearing to the host as a disk drive or as a CD-ROM drive. In
14 * addition to providing an example of a genuinely useful composite
15 * function for a USB device, it also illustrates a technique of
16 * double-buffering for increased throughput.
17 *
18 * Function supports multiple logical units (LUNs). Backing storage
19 * for each LUN is provided by a regular file or a block device.
20 * Access for each LUN can be limited to read-only. Moreover, the
21 * function can indicate that LUN is removable and/or CD-ROM. (The
22 * later implies read-only access.)
23 *
24 * MSF is configured by specifying a fsg_config structure. It has the
25 * following fields:
26 *
27 * nluns Number of LUNs function have (anywhere from 1
28 * to FSG_MAX_LUNS which is 8).
29 * luns An array of LUN configuration values. This
30 * should be filled for each LUN that
31 * function will include (ie. for "nluns"
32 * LUNs). Each element of the array has
33 * the following fields:
34 * ->filename The path to the backing file for the LUN.
35 * Required if LUN is not marked as
36 * removable.
37 * ->ro Flag specifying access to the LUN shall be
38 * read-only. This is implied if CD-ROM
39 * emulation is enabled as well as when
40 * it was impossible to open "filename"
41 * in R/W mode.
42 * ->removable Flag specifying that LUN shall be indicated as
43 * being removable.
44 * ->cdrom Flag specifying that LUN shall be reported as
45 * being a CD-ROM.
46 *
47 * lun_name_format A printf-like format for names of the LUN
48 * devices. This determines how the
49 * directory in sysfs will be named.
50 * Unless you are using several MSFs in
51 * a single gadget (as opposed to single
52 * MSF in many configurations) you may
53 * leave it as NULL (in which case
54 * "lun%d" will be used). In the format
55 * you can use "%d" to index LUNs for
56 * MSF's with more than one LUN. (Beware
57 * that there is only one integer given
58 * as an argument for the format and
59 * specifying invalid format may cause
60 * unspecified behaviour.)
61 * thread_name Name of the kernel thread process used by the
62 * MSF. You can safely set it to NULL
63 * (in which case default "file-storage"
64 * will be used).
65 *
66 * vendor_name
67 * product_name
68 * release Information used as a reply to INQUIRY
69 * request. To use default set to NULL,
70 * NULL, 0xffff respectively. The first
71 * field should be 8 and the second 16
72 * characters or less.
73 *
74 * can_stall Set to permit function to halt bulk endpoints.
75 * Disabled on some USB devices known not
76 * to work correctly. You should set it
77 * to true.
78 *
79 * If "removable" is not set for a LUN then a backing file must be
80 * specified. If it is set, then NULL filename means the LUN's medium
81 * is not loaded (an empty string as "filename" in the fsg_config
82 * structure causes error). The CD-ROM emulation includes a single
83 * data track and no audio tracks; hence there need be only one
84 * backing file per LUN. Note also that the CD-ROM block length is
85 * set to 512 rather than the more common value 2048.
86 *
87 *
88 * MSF includes support for module parameters. If gadget using it
89 * decides to use it, the following module parameters will be
90 * available:
91 *
92 * file=filename[,filename...]
93 * Names of the files or block devices used for
94 * backing storage.
95 * ro=b[,b...] Default false, boolean for read-only access.
96 * removable=b[,b...]
97 * Default true, boolean for removable media.
98 * cdrom=b[,b...] Default false, boolean for whether to emulate
99 * a CD-ROM drive.
100 * luns=N Default N = number of filenames, number of
101 * LUNs to support.
102 * stall Default determined according to the type of
103 * USB device controller (usually true),
104 * boolean to permit the driver to halt
105 * bulk endpoints.
106 *
107 * The module parameters may be prefixed with some string. You need
108 * to consult gadget's documentation or source to verify whether it is
109 * using those module parameters and if it does what are the prefixes
110 * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
111 * the prefix).
112 *
113 *
114 * Requirements are modest; only a bulk-in and a bulk-out endpoint are
115 * needed. The memory requirement amounts to two 16K buffers, size
116 * configurable by a parameter. Support is included for both
117 * full-speed and high-speed operation.
118 *
119 * Note that the driver is slightly non-portable in that it assumes a
120 * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
121 * interrupt-in endpoints. With most device controllers this isn't an
122 * issue, but there may be some with hardware restrictions that prevent
123 * a buffer from being used by more than one endpoint.
124 *
125 *
126 * The pathnames of the backing files and the ro settings are
127 * available in the attribute files "file" and "ro" in the lun<n> (or
128 * to be more precise in a directory which name comes from
129 * "lun_name_format" option!) subdirectory of the gadget's sysfs
130 * directory. If the "removable" option is set, writing to these
131 * files will simulate ejecting/loading the medium (writing an empty
132 * line means eject) and adjusting a write-enable tab. Changes to the
133 * ro setting are not allowed when the medium is loaded or if CD-ROM
134 * emulation is being used.
135 *
136 * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
137 * if the LUN is removable, the backing file is released to simulate
138 * ejection.
139 *
140 *
141 * This function is heavily based on "File-backed Storage Gadget" by
142 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
143 * Brownell. The driver's SCSI command interface was based on the
144 * "Information technology - Small Computer System Interface - 2"
145 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
146 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
147 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
148 * was based on the "Universal Serial Bus Mass Storage Class UFI
149 * Command Specification" document, Revision 1.0, December 14, 1998,
150 * available at
151 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
152 */
153
154 /*
155 * Driver Design
156 *
157 * The MSF is fairly straightforward. There is a main kernel
158 * thread that handles most of the work. Interrupt routines field
159 * callbacks from the controller driver: bulk- and interrupt-request
160 * completion notifications, endpoint-0 events, and disconnect events.
161 * Completion events are passed to the main thread by wakeup calls. Many
162 * ep0 requests are handled at interrupt time, but SetInterface,
163 * SetConfiguration, and device reset requests are forwarded to the
164 * thread in the form of "exceptions" using SIGUSR1 signals (since they
165 * should interrupt any ongoing file I/O operations).
166 *
167 * The thread's main routine implements the standard command/data/status
168 * parts of a SCSI interaction. It and its subroutines are full of tests
169 * for pending signals/exceptions -- all this polling is necessary since
170 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
171 * indication that the driver really wants to be running in userspace.)
172 * An important point is that so long as the thread is alive it keeps an
173 * open reference to the backing file. This will prevent unmounting
174 * the backing file's underlying filesystem and could cause problems
175 * during system shutdown, for example. To prevent such problems, the
176 * thread catches INT, TERM, and KILL signals and converts them into
177 * an EXIT exception.
178 *
179 * In normal operation the main thread is started during the gadget's
180 * fsg_bind() callback and stopped during fsg_unbind(). But it can
181 * also exit when it receives a signal, and there's no point leaving
182 * the gadget running when the thread is dead. At of this moment, MSF
183 * provides no way to deregister the gadget when thread dies -- maybe
184 * a callback functions is needed.
185 *
186 * To provide maximum throughput, the driver uses a circular pipeline of
187 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
188 * arbitrarily long; in practice the benefits don't justify having more
189 * than 2 stages (i.e., double buffering). But it helps to think of the
190 * pipeline as being a long one. Each buffer head contains a bulk-in and
191 * a bulk-out request pointer (since the buffer can be used for both
192 * output and input -- directions always are given from the host's
193 * point of view) as well as a pointer to the buffer and various state
194 * variables.
195 *
196 * Use of the pipeline follows a simple protocol. There is a variable
197 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
198 * At any time that buffer head may still be in use from an earlier
199 * request, so each buffer head has a state variable indicating whether
200 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
201 * buffer head to be EMPTY, filling the buffer either by file I/O or by
202 * USB I/O (during which the buffer head is BUSY), and marking the buffer
203 * head FULL when the I/O is complete. Then the buffer will be emptied
204 * (again possibly by USB I/O, during which it is marked BUSY) and
205 * finally marked EMPTY again (possibly by a completion routine).
206 *
207 * A module parameter tells the driver to avoid stalling the bulk
208 * endpoints wherever the transport specification allows. This is
209 * necessary for some UDCs like the SuperH, which cannot reliably clear a
210 * halt on a bulk endpoint. However, under certain circumstances the
211 * Bulk-only specification requires a stall. In such cases the driver
212 * will halt the endpoint and set a flag indicating that it should clear
213 * the halt in software during the next device reset. Hopefully this
214 * will permit everything to work correctly. Furthermore, although the
215 * specification allows the bulk-out endpoint to halt when the host sends
216 * too much data, implementing this would cause an unavoidable race.
217 * The driver will always use the "no-stall" approach for OUT transfers.
218 *
219 * One subtle point concerns sending status-stage responses for ep0
220 * requests. Some of these requests, such as device reset, can involve
221 * interrupting an ongoing file I/O operation, which might take an
222 * arbitrarily long time. During that delay the host might give up on
223 * the original ep0 request and issue a new one. When that happens the
224 * driver should not notify the host about completion of the original
225 * request, as the host will no longer be waiting for it. So the driver
226 * assigns to each ep0 request a unique tag, and it keeps track of the
227 * tag value of the request associated with a long-running exception
228 * (device-reset, interface-change, or configuration-change). When the
229 * exception handler is finished, the status-stage response is submitted
230 * only if the current ep0 request tag is equal to the exception request
231 * tag. Thus only the most recently received ep0 request will get a
232 * status-stage response.
233 *
234 * Warning: This driver source file is too long. It ought to be split up
235 * into a header file plus about 3 separate .c files, to handle the details
236 * of the Gadget, USB Mass Storage, and SCSI protocols.
237 */
238
239 /* #define VERBOSE_DEBUG */
240 /* #define DUMP_MSGS */
241
242 #include <config.h>
243 #include <hexdump.h>
244 #include <malloc.h>
245 #include <common.h>
246 #include <console.h>
247 #include <g_dnl.h>
248
249 #include <linux/err.h>
250 #include <linux/usb/ch9.h>
251 #include <linux/usb/gadget.h>
252 #include <usb_mass_storage.h>
253
254 #include <asm/unaligned.h>
255 #include <linux/bitops.h>
256 #include <linux/usb/gadget.h>
257 #include <linux/usb/gadget.h>
258 #include <linux/usb/composite.h>
259 #include <usb/lin_gadget_compat.h>
260 #include <g_dnl.h>
261
262 /*------------------------------------------------------------------------*/
263
264 #define FSG_DRIVER_DESC "Mass Storage Function"
265 #define FSG_DRIVER_VERSION "2012/06/5"
266
267 static const char fsg_string_interface[] = "Mass Storage";
268
269 #define FSG_NO_INTR_EP 1
270 #define FSG_NO_DEVICE_STRINGS 1
271 #define FSG_NO_OTG 1
272 #define FSG_NO_INTR_EP 1
273
274 #include "storage_common.c"
275
276 /*-------------------------------------------------------------------------*/
277
278 #define GFP_ATOMIC ((gfp_t) 0)
279 #define PAGE_CACHE_SHIFT 12
280 #define PAGE_CACHE_SIZE (1 << PAGE_CACHE_SHIFT)
281 #define kthread_create(...) __builtin_return_address(0)
282 #define wait_for_completion(...) do {} while (0)
283
284 struct kref {int x; };
285 struct completion {int x; };
286
287 struct fsg_dev;
288 struct fsg_common;
289
290 /* Data shared by all the FSG instances. */
291 struct fsg_common {
292 struct usb_gadget *gadget;
293 struct fsg_dev *fsg, *new_fsg;
294
295 struct usb_ep *ep0; /* Copy of gadget->ep0 */
296 struct usb_request *ep0req; /* Copy of cdev->req */
297 unsigned int ep0_req_tag;
298
299 struct fsg_buffhd *next_buffhd_to_fill;
300 struct fsg_buffhd *next_buffhd_to_drain;
301 struct fsg_buffhd buffhds[FSG_NUM_BUFFERS];
302
303 int cmnd_size;
304 u8 cmnd[MAX_COMMAND_SIZE];
305
306 unsigned int nluns;
307 unsigned int lun;
308 struct fsg_lun luns[FSG_MAX_LUNS];
309
310 unsigned int bulk_out_maxpacket;
311 enum fsg_state state; /* For exception handling */
312 unsigned int exception_req_tag;
313
314 enum data_direction data_dir;
315 u32 data_size;
316 u32 data_size_from_cmnd;
317 u32 tag;
318 u32 residue;
319 u32 usb_amount_left;
320
321 unsigned int can_stall:1;
322 unsigned int free_storage_on_release:1;
323 unsigned int phase_error:1;
324 unsigned int short_packet_received:1;
325 unsigned int bad_lun_okay:1;
326 unsigned int running:1;
327
328 int thread_wakeup_needed;
329 struct completion thread_notifier;
330 struct task_struct *thread_task;
331
332 /* Callback functions. */
333 const struct fsg_operations *ops;
334 /* Gadget's private data. */
335 void *private_data;
336
337 const char *vendor_name; /* 8 characters or less */
338 const char *product_name; /* 16 characters or less */
339 u16 release;
340
341 /* Vendor (8 chars), product (16 chars), release (4
342 * hexadecimal digits) and NUL byte */
343 char inquiry_string[8 + 16 + 4 + 1];
344
345 struct kref ref;
346 };
347
348 struct fsg_config {
349 unsigned nluns;
350 struct fsg_lun_config {
351 const char *filename;
352 char ro;
353 char removable;
354 char cdrom;
355 char nofua;
356 } luns[FSG_MAX_LUNS];
357
358 /* Callback functions. */
359 const struct fsg_operations *ops;
360 /* Gadget's private data. */
361 void *private_data;
362
363 const char *vendor_name; /* 8 characters or less */
364 const char *product_name; /* 16 characters or less */
365
366 char can_stall;
367 };
368
369 struct fsg_dev {
370 struct usb_function function;
371 struct usb_gadget *gadget; /* Copy of cdev->gadget */
372 struct fsg_common *common;
373
374 u16 interface_number;
375
376 unsigned int bulk_in_enabled:1;
377 unsigned int bulk_out_enabled:1;
378
379 unsigned long atomic_bitflags;
380 #define IGNORE_BULK_OUT 0
381
382 struct usb_ep *bulk_in;
383 struct usb_ep *bulk_out;
384 };
385
386
__fsg_is_set(struct fsg_common * common,const char * func,unsigned line)387 static inline int __fsg_is_set(struct fsg_common *common,
388 const char *func, unsigned line)
389 {
390 if (common->fsg)
391 return 1;
392 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
393 WARN_ON(1);
394 return 0;
395 }
396
397 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
398
399
fsg_from_func(struct usb_function * f)400 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
401 {
402 return container_of(f, struct fsg_dev, function);
403 }
404
405
406 typedef void (*fsg_routine_t)(struct fsg_dev *);
407
exception_in_progress(struct fsg_common * common)408 static int exception_in_progress(struct fsg_common *common)
409 {
410 return common->state > FSG_STATE_IDLE;
411 }
412
413 /* Make bulk-out requests be divisible by the maxpacket size */
set_bulk_out_req_length(struct fsg_common * common,struct fsg_buffhd * bh,unsigned int length)414 static void set_bulk_out_req_length(struct fsg_common *common,
415 struct fsg_buffhd *bh, unsigned int length)
416 {
417 unsigned int rem;
418
419 bh->bulk_out_intended_length = length;
420 rem = length % common->bulk_out_maxpacket;
421 if (rem > 0)
422 length += common->bulk_out_maxpacket - rem;
423 bh->outreq->length = length;
424 }
425
426 /*-------------------------------------------------------------------------*/
427
428 static struct ums *ums;
429 static int ums_count;
430 static struct fsg_common *the_fsg_common;
431
fsg_set_halt(struct fsg_dev * fsg,struct usb_ep * ep)432 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
433 {
434 const char *name;
435
436 if (ep == fsg->bulk_in)
437 name = "bulk-in";
438 else if (ep == fsg->bulk_out)
439 name = "bulk-out";
440 else
441 name = ep->name;
442 DBG(fsg, "%s set halt\n", name);
443 return usb_ep_set_halt(ep);
444 }
445
446 /*-------------------------------------------------------------------------*/
447
448 /* These routines may be called in process context or in_irq */
449
450 /* Caller must hold fsg->lock */
wakeup_thread(struct fsg_common * common)451 static void wakeup_thread(struct fsg_common *common)
452 {
453 common->thread_wakeup_needed = 1;
454 }
455
raise_exception(struct fsg_common * common,enum fsg_state new_state)456 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
457 {
458 /* Do nothing if a higher-priority exception is already in progress.
459 * If a lower-or-equal priority exception is in progress, preempt it
460 * and notify the main thread by sending it a signal. */
461 if (common->state <= new_state) {
462 common->exception_req_tag = common->ep0_req_tag;
463 common->state = new_state;
464 common->thread_wakeup_needed = 1;
465 }
466 }
467
468 /*-------------------------------------------------------------------------*/
469
ep0_queue(struct fsg_common * common)470 static int ep0_queue(struct fsg_common *common)
471 {
472 int rc;
473
474 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
475 common->ep0->driver_data = common;
476 if (rc != 0 && rc != -ESHUTDOWN) {
477 /* We can't do much more than wait for a reset */
478 WARNING(common, "error in submission: %s --> %d\n",
479 common->ep0->name, rc);
480 }
481 return rc;
482 }
483
484 /*-------------------------------------------------------------------------*/
485
486 /* Bulk and interrupt endpoint completion handlers.
487 * These always run in_irq. */
488
bulk_in_complete(struct usb_ep * ep,struct usb_request * req)489 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
490 {
491 struct fsg_common *common = ep->driver_data;
492 struct fsg_buffhd *bh = req->context;
493
494 if (req->status || req->actual != req->length)
495 DBG(common, "%s --> %d, %u/%u\n", __func__,
496 req->status, req->actual, req->length);
497 if (req->status == -ECONNRESET) /* Request was cancelled */
498 usb_ep_fifo_flush(ep);
499
500 /* Hold the lock while we update the request and buffer states */
501 bh->inreq_busy = 0;
502 bh->state = BUF_STATE_EMPTY;
503 wakeup_thread(common);
504 }
505
bulk_out_complete(struct usb_ep * ep,struct usb_request * req)506 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
507 {
508 struct fsg_common *common = ep->driver_data;
509 struct fsg_buffhd *bh = req->context;
510
511 dump_msg(common, "bulk-out", req->buf, req->actual);
512 if (req->status || req->actual != bh->bulk_out_intended_length)
513 DBG(common, "%s --> %d, %u/%u\n", __func__,
514 req->status, req->actual,
515 bh->bulk_out_intended_length);
516 if (req->status == -ECONNRESET) /* Request was cancelled */
517 usb_ep_fifo_flush(ep);
518
519 /* Hold the lock while we update the request and buffer states */
520 bh->outreq_busy = 0;
521 bh->state = BUF_STATE_FULL;
522 wakeup_thread(common);
523 }
524
525 /*-------------------------------------------------------------------------*/
526
527 /* Ep0 class-specific handlers. These always run in_irq. */
528
fsg_setup(struct usb_function * f,const struct usb_ctrlrequest * ctrl)529 static int fsg_setup(struct usb_function *f,
530 const struct usb_ctrlrequest *ctrl)
531 {
532 struct fsg_dev *fsg = fsg_from_func(f);
533 struct usb_request *req = fsg->common->ep0req;
534 u16 w_index = get_unaligned_le16(&ctrl->wIndex);
535 u16 w_value = get_unaligned_le16(&ctrl->wValue);
536 u16 w_length = get_unaligned_le16(&ctrl->wLength);
537
538 if (!fsg_is_set(fsg->common))
539 return -EOPNOTSUPP;
540
541 switch (ctrl->bRequest) {
542
543 case USB_BULK_RESET_REQUEST:
544 if (ctrl->bRequestType !=
545 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
546 break;
547 if (w_index != fsg->interface_number || w_value != 0)
548 return -EDOM;
549
550 /* Raise an exception to stop the current operation
551 * and reinitialize our state. */
552 DBG(fsg, "bulk reset request\n");
553 raise_exception(fsg->common, FSG_STATE_RESET);
554 return DELAYED_STATUS;
555
556 case USB_BULK_GET_MAX_LUN_REQUEST:
557 if (ctrl->bRequestType !=
558 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
559 break;
560 if (w_index != fsg->interface_number || w_value != 0)
561 return -EDOM;
562 VDBG(fsg, "get max LUN\n");
563 *(u8 *) req->buf = fsg->common->nluns - 1;
564
565 /* Respond with data/status */
566 req->length = min((u16)1, w_length);
567 return ep0_queue(fsg->common);
568 }
569
570 VDBG(fsg,
571 "unknown class-specific control req "
572 "%02x.%02x v%04x i%04x l%u\n",
573 ctrl->bRequestType, ctrl->bRequest,
574 get_unaligned_le16(&ctrl->wValue), w_index, w_length);
575 return -EOPNOTSUPP;
576 }
577
578 /*-------------------------------------------------------------------------*/
579
580 /* All the following routines run in process context */
581
582 /* Use this for bulk or interrupt transfers, not ep0 */
start_transfer(struct fsg_dev * fsg,struct usb_ep * ep,struct usb_request * req,int * pbusy,enum fsg_buffer_state * state)583 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
584 struct usb_request *req, int *pbusy,
585 enum fsg_buffer_state *state)
586 {
587 int rc;
588
589 if (ep == fsg->bulk_in)
590 dump_msg(fsg, "bulk-in", req->buf, req->length);
591
592 *pbusy = 1;
593 *state = BUF_STATE_BUSY;
594 rc = usb_ep_queue(ep, req, GFP_KERNEL);
595 if (rc != 0) {
596 *pbusy = 0;
597 *state = BUF_STATE_EMPTY;
598
599 /* We can't do much more than wait for a reset */
600
601 /* Note: currently the net2280 driver fails zero-length
602 * submissions if DMA is enabled. */
603 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
604 req->length == 0))
605 WARNING(fsg, "error in submission: %s --> %d\n",
606 ep->name, rc);
607 }
608 }
609
610 #define START_TRANSFER_OR(common, ep_name, req, pbusy, state) \
611 if (fsg_is_set(common)) \
612 start_transfer((common)->fsg, (common)->fsg->ep_name, \
613 req, pbusy, state); \
614 else
615
616 #define START_TRANSFER(common, ep_name, req, pbusy, state) \
617 START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
618
busy_indicator(void)619 static void busy_indicator(void)
620 {
621 static int state;
622
623 switch (state) {
624 case 0:
625 puts("\r|"); break;
626 case 1:
627 puts("\r/"); break;
628 case 2:
629 puts("\r-"); break;
630 case 3:
631 puts("\r\\"); break;
632 case 4:
633 puts("\r|"); break;
634 case 5:
635 puts("\r/"); break;
636 case 6:
637 puts("\r-"); break;
638 case 7:
639 puts("\r\\"); break;
640 default:
641 state = 0;
642 }
643 if (state++ == 8)
644 state = 0;
645 }
646
sleep_thread(struct fsg_common * common)647 static int sleep_thread(struct fsg_common *common)
648 {
649 int rc = 0;
650 int i = 0, k = 0;
651
652 /* Wait until a signal arrives or we are woken up */
653 for (;;) {
654 if (common->thread_wakeup_needed)
655 break;
656
657 if (++i == 20000) {
658 busy_indicator();
659 i = 0;
660 k++;
661 }
662
663 if (k == 10) {
664 /* Handle CTRL+C */
665 if (ctrlc())
666 return -EPIPE;
667
668 /* Check cable connection */
669 if (!g_dnl_board_usb_cable_connected())
670 return -EIO;
671
672 k = 0;
673 }
674
675 usb_gadget_handle_interrupts(0);
676 }
677 common->thread_wakeup_needed = 0;
678 return rc;
679 }
680
681 /*-------------------------------------------------------------------------*/
682
do_read(struct fsg_common * common)683 static int do_read(struct fsg_common *common)
684 {
685 struct fsg_lun *curlun = &common->luns[common->lun];
686 u32 lba;
687 struct fsg_buffhd *bh;
688 int rc;
689 u32 amount_left;
690 loff_t file_offset;
691 unsigned int amount;
692 unsigned int partial_page;
693 ssize_t nread;
694
695 /* Get the starting Logical Block Address and check that it's
696 * not too big */
697 if (common->cmnd[0] == SC_READ_6)
698 lba = get_unaligned_be24(&common->cmnd[1]);
699 else {
700 lba = get_unaligned_be32(&common->cmnd[2]);
701
702 /* We allow DPO (Disable Page Out = don't save data in the
703 * cache) and FUA (Force Unit Access = don't read from the
704 * cache), but we don't implement them. */
705 if ((common->cmnd[1] & ~0x18) != 0) {
706 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
707 return -EINVAL;
708 }
709 }
710 if (lba >= curlun->num_sectors) {
711 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
712 return -EINVAL;
713 }
714 file_offset = ((loff_t) lba) << 9;
715
716 /* Carry out the file reads */
717 amount_left = common->data_size_from_cmnd;
718 if (unlikely(amount_left == 0))
719 return -EIO; /* No default reply */
720
721 for (;;) {
722
723 /* Figure out how much we need to read:
724 * Try to read the remaining amount.
725 * But don't read more than the buffer size.
726 * And don't try to read past the end of the file.
727 * Finally, if we're not at a page boundary, don't read past
728 * the next page.
729 * If this means reading 0 then we were asked to read past
730 * the end of file. */
731 amount = min(amount_left, FSG_BUFLEN);
732 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
733 if (partial_page > 0)
734 amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
735 partial_page);
736
737 /* Wait for the next buffer to become available */
738 bh = common->next_buffhd_to_fill;
739 while (bh->state != BUF_STATE_EMPTY) {
740 rc = sleep_thread(common);
741 if (rc)
742 return rc;
743 }
744
745 /* If we were asked to read past the end of file,
746 * end with an empty buffer. */
747 if (amount == 0) {
748 curlun->sense_data =
749 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
750 curlun->info_valid = 1;
751 bh->inreq->length = 0;
752 bh->state = BUF_STATE_FULL;
753 break;
754 }
755
756 /* Perform the read */
757 rc = ums[common->lun].read_sector(&ums[common->lun],
758 file_offset / SECTOR_SIZE,
759 amount / SECTOR_SIZE,
760 (char __user *)bh->buf);
761 if (!rc)
762 return -EIO;
763
764 nread = rc * SECTOR_SIZE;
765
766 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
767 (unsigned long long) file_offset,
768 (int) nread);
769
770 if (nread < 0) {
771 LDBG(curlun, "error in file read: %d\n",
772 (int) nread);
773 nread = 0;
774 } else if (nread < amount) {
775 LDBG(curlun, "partial file read: %d/%u\n",
776 (int) nread, amount);
777 nread -= (nread & 511); /* Round down to a block */
778 }
779 file_offset += nread;
780 amount_left -= nread;
781 common->residue -= nread;
782 bh->inreq->length = nread;
783 bh->state = BUF_STATE_FULL;
784
785 /* If an error occurred, report it and its position */
786 if (nread < amount) {
787 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
788 curlun->info_valid = 1;
789 break;
790 }
791
792 if (amount_left == 0)
793 break; /* No more left to read */
794
795 /* Send this buffer and go read some more */
796 bh->inreq->zero = 0;
797 START_TRANSFER_OR(common, bulk_in, bh->inreq,
798 &bh->inreq_busy, &bh->state)
799 /* Don't know what to do if
800 * common->fsg is NULL */
801 return -EIO;
802 common->next_buffhd_to_fill = bh->next;
803 }
804
805 return -EIO; /* No default reply */
806 }
807
808 /*-------------------------------------------------------------------------*/
809
do_write(struct fsg_common * common)810 static int do_write(struct fsg_common *common)
811 {
812 struct fsg_lun *curlun = &common->luns[common->lun];
813 u32 lba;
814 struct fsg_buffhd *bh;
815 int get_some_more;
816 u32 amount_left_to_req, amount_left_to_write;
817 loff_t usb_offset, file_offset;
818 unsigned int amount;
819 unsigned int partial_page;
820 ssize_t nwritten;
821 int rc;
822
823 if (curlun->ro) {
824 curlun->sense_data = SS_WRITE_PROTECTED;
825 return -EINVAL;
826 }
827
828 /* Get the starting Logical Block Address and check that it's
829 * not too big */
830 if (common->cmnd[0] == SC_WRITE_6)
831 lba = get_unaligned_be24(&common->cmnd[1]);
832 else {
833 lba = get_unaligned_be32(&common->cmnd[2]);
834
835 /* We allow DPO (Disable Page Out = don't save data in the
836 * cache) and FUA (Force Unit Access = write directly to the
837 * medium). We don't implement DPO; we implement FUA by
838 * performing synchronous output. */
839 if (common->cmnd[1] & ~0x18) {
840 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
841 return -EINVAL;
842 }
843 }
844 if (lba >= curlun->num_sectors) {
845 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
846 return -EINVAL;
847 }
848
849 /* Carry out the file writes */
850 get_some_more = 1;
851 file_offset = usb_offset = ((loff_t) lba) << 9;
852 amount_left_to_req = common->data_size_from_cmnd;
853 amount_left_to_write = common->data_size_from_cmnd;
854
855 while (amount_left_to_write > 0) {
856
857 /* Queue a request for more data from the host */
858 bh = common->next_buffhd_to_fill;
859 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
860
861 /* Figure out how much we want to get:
862 * Try to get the remaining amount.
863 * But don't get more than the buffer size.
864 * And don't try to go past the end of the file.
865 * If we're not at a page boundary,
866 * don't go past the next page.
867 * If this means getting 0, then we were asked
868 * to write past the end of file.
869 * Finally, round down to a block boundary. */
870 amount = min(amount_left_to_req, FSG_BUFLEN);
871 partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
872 if (partial_page > 0)
873 amount = min(amount,
874 (unsigned int) PAGE_CACHE_SIZE - partial_page);
875
876 if (amount == 0) {
877 get_some_more = 0;
878 curlun->sense_data =
879 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
880 curlun->info_valid = 1;
881 continue;
882 }
883 amount -= (amount & 511);
884 if (amount == 0) {
885
886 /* Why were we were asked to transfer a
887 * partial block? */
888 get_some_more = 0;
889 continue;
890 }
891
892 /* Get the next buffer */
893 usb_offset += amount;
894 common->usb_amount_left -= amount;
895 amount_left_to_req -= amount;
896 if (amount_left_to_req == 0)
897 get_some_more = 0;
898
899 /* amount is always divisible by 512, hence by
900 * the bulk-out maxpacket size */
901 bh->outreq->length = amount;
902 bh->bulk_out_intended_length = amount;
903 bh->outreq->short_not_ok = 1;
904 START_TRANSFER_OR(common, bulk_out, bh->outreq,
905 &bh->outreq_busy, &bh->state)
906 /* Don't know what to do if
907 * common->fsg is NULL */
908 return -EIO;
909 common->next_buffhd_to_fill = bh->next;
910 continue;
911 }
912
913 /* Write the received data to the backing file */
914 bh = common->next_buffhd_to_drain;
915 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
916 break; /* We stopped early */
917 if (bh->state == BUF_STATE_FULL) {
918 common->next_buffhd_to_drain = bh->next;
919 bh->state = BUF_STATE_EMPTY;
920
921 /* Did something go wrong with the transfer? */
922 if (bh->outreq->status != 0) {
923 curlun->sense_data = SS_COMMUNICATION_FAILURE;
924 curlun->info_valid = 1;
925 break;
926 }
927
928 amount = bh->outreq->actual;
929
930 /* Perform the write */
931 rc = ums[common->lun].write_sector(&ums[common->lun],
932 file_offset / SECTOR_SIZE,
933 amount / SECTOR_SIZE,
934 (char __user *)bh->buf);
935 if (!rc)
936 return -EIO;
937 nwritten = rc * SECTOR_SIZE;
938
939 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
940 (unsigned long long) file_offset,
941 (int) nwritten);
942
943 if (nwritten < 0) {
944 LDBG(curlun, "error in file write: %d\n",
945 (int) nwritten);
946 nwritten = 0;
947 } else if (nwritten < amount) {
948 LDBG(curlun, "partial file write: %d/%u\n",
949 (int) nwritten, amount);
950 nwritten -= (nwritten & 511);
951 /* Round down to a block */
952 }
953 file_offset += nwritten;
954 amount_left_to_write -= nwritten;
955 common->residue -= nwritten;
956
957 /* If an error occurred, report it and its position */
958 if (nwritten < amount) {
959 printf("nwritten:%zd amount:%u\n", nwritten,
960 amount);
961 curlun->sense_data = SS_WRITE_ERROR;
962 curlun->info_valid = 1;
963 break;
964 }
965
966 /* Did the host decide to stop early? */
967 if (bh->outreq->actual != bh->outreq->length) {
968 common->short_packet_received = 1;
969 break;
970 }
971 continue;
972 }
973
974 /* Wait for something to happen */
975 rc = sleep_thread(common);
976 if (rc)
977 return rc;
978 }
979
980 return -EIO; /* No default reply */
981 }
982
983 /*-------------------------------------------------------------------------*/
984
do_synchronize_cache(struct fsg_common * common)985 static int do_synchronize_cache(struct fsg_common *common)
986 {
987 return 0;
988 }
989
990 /*-------------------------------------------------------------------------*/
991
do_verify(struct fsg_common * common)992 static int do_verify(struct fsg_common *common)
993 {
994 struct fsg_lun *curlun = &common->luns[common->lun];
995 u32 lba;
996 u32 verification_length;
997 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
998 loff_t file_offset;
999 u32 amount_left;
1000 unsigned int amount;
1001 ssize_t nread;
1002 int rc;
1003
1004 /* Get the starting Logical Block Address and check that it's
1005 * not too big */
1006 lba = get_unaligned_be32(&common->cmnd[2]);
1007 if (lba >= curlun->num_sectors) {
1008 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1009 return -EINVAL;
1010 }
1011
1012 /* We allow DPO (Disable Page Out = don't save data in the
1013 * cache) but we don't implement it. */
1014 if (common->cmnd[1] & ~0x10) {
1015 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1016 return -EINVAL;
1017 }
1018
1019 verification_length = get_unaligned_be16(&common->cmnd[7]);
1020 if (unlikely(verification_length == 0))
1021 return -EIO; /* No default reply */
1022
1023 /* Prepare to carry out the file verify */
1024 amount_left = verification_length << 9;
1025 file_offset = ((loff_t) lba) << 9;
1026
1027 /* Write out all the dirty buffers before invalidating them */
1028
1029 /* Just try to read the requested blocks */
1030 while (amount_left > 0) {
1031
1032 /* Figure out how much we need to read:
1033 * Try to read the remaining amount, but not more than
1034 * the buffer size.
1035 * And don't try to read past the end of the file.
1036 * If this means reading 0 then we were asked to read
1037 * past the end of file. */
1038 amount = min(amount_left, FSG_BUFLEN);
1039 if (amount == 0) {
1040 curlun->sense_data =
1041 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1042 curlun->info_valid = 1;
1043 break;
1044 }
1045
1046 /* Perform the read */
1047 rc = ums[common->lun].read_sector(&ums[common->lun],
1048 file_offset / SECTOR_SIZE,
1049 amount / SECTOR_SIZE,
1050 (char __user *)bh->buf);
1051 if (!rc)
1052 return -EIO;
1053 nread = rc * SECTOR_SIZE;
1054
1055 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1056 (unsigned long long) file_offset,
1057 (int) nread);
1058 if (nread < 0) {
1059 LDBG(curlun, "error in file verify: %d\n",
1060 (int) nread);
1061 nread = 0;
1062 } else if (nread < amount) {
1063 LDBG(curlun, "partial file verify: %d/%u\n",
1064 (int) nread, amount);
1065 nread -= (nread & 511); /* Round down to a sector */
1066 }
1067 if (nread == 0) {
1068 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1069 curlun->info_valid = 1;
1070 break;
1071 }
1072 file_offset += nread;
1073 amount_left -= nread;
1074 }
1075 return 0;
1076 }
1077
1078 /*-------------------------------------------------------------------------*/
1079
do_inquiry(struct fsg_common * common,struct fsg_buffhd * bh)1080 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1081 {
1082 struct fsg_lun *curlun = &common->luns[common->lun];
1083 static const char vendor_id[] = "Linux ";
1084 u8 *buf = (u8 *) bh->buf;
1085
1086 if (!curlun) { /* Unsupported LUNs are okay */
1087 common->bad_lun_okay = 1;
1088 memset(buf, 0, 36);
1089 buf[0] = 0x7f; /* Unsupported, no device-type */
1090 buf[4] = 31; /* Additional length */
1091 return 36;
1092 }
1093
1094 memset(buf, 0, 8);
1095 buf[0] = TYPE_DISK;
1096 buf[1] = curlun->removable ? 0x80 : 0;
1097 buf[2] = 2; /* ANSI SCSI level 2 */
1098 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1099 buf[4] = 31; /* Additional length */
1100 /* No special options */
1101 sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
1102 ums[common->lun].name, (u16) 0xffff);
1103
1104 return 36;
1105 }
1106
1107
do_request_sense(struct fsg_common * common,struct fsg_buffhd * bh)1108 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1109 {
1110 struct fsg_lun *curlun = &common->luns[common->lun];
1111 u8 *buf = (u8 *) bh->buf;
1112 u32 sd, sdinfo;
1113 int valid;
1114
1115 /*
1116 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1117 *
1118 * If a REQUEST SENSE command is received from an initiator
1119 * with a pending unit attention condition (before the target
1120 * generates the contingent allegiance condition), then the
1121 * target shall either:
1122 * a) report any pending sense data and preserve the unit
1123 * attention condition on the logical unit, or,
1124 * b) report the unit attention condition, may discard any
1125 * pending sense data, and clear the unit attention
1126 * condition on the logical unit for that initiator.
1127 *
1128 * FSG normally uses option a); enable this code to use option b).
1129 */
1130 #if 0
1131 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1132 curlun->sense_data = curlun->unit_attention_data;
1133 curlun->unit_attention_data = SS_NO_SENSE;
1134 }
1135 #endif
1136
1137 if (!curlun) { /* Unsupported LUNs are okay */
1138 common->bad_lun_okay = 1;
1139 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1140 sdinfo = 0;
1141 valid = 0;
1142 } else {
1143 sd = curlun->sense_data;
1144 valid = curlun->info_valid << 7;
1145 curlun->sense_data = SS_NO_SENSE;
1146 curlun->info_valid = 0;
1147 }
1148
1149 memset(buf, 0, 18);
1150 buf[0] = valid | 0x70; /* Valid, current error */
1151 buf[2] = SK(sd);
1152 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1153 buf[7] = 18 - 8; /* Additional sense length */
1154 buf[12] = ASC(sd);
1155 buf[13] = ASCQ(sd);
1156 return 18;
1157 }
1158
do_read_capacity(struct fsg_common * common,struct fsg_buffhd * bh)1159 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1160 {
1161 struct fsg_lun *curlun = &common->luns[common->lun];
1162 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1163 int pmi = common->cmnd[8];
1164 u8 *buf = (u8 *) bh->buf;
1165
1166 /* Check the PMI and LBA fields */
1167 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1168 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1169 return -EINVAL;
1170 }
1171
1172 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1173 /* Max logical block */
1174 put_unaligned_be32(512, &buf[4]); /* Block length */
1175 return 8;
1176 }
1177
do_read_header(struct fsg_common * common,struct fsg_buffhd * bh)1178 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1179 {
1180 struct fsg_lun *curlun = &common->luns[common->lun];
1181 int msf = common->cmnd[1] & 0x02;
1182 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1183 u8 *buf = (u8 *) bh->buf;
1184
1185 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1186 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1187 return -EINVAL;
1188 }
1189 if (lba >= curlun->num_sectors) {
1190 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1191 return -EINVAL;
1192 }
1193
1194 memset(buf, 0, 8);
1195 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1196 store_cdrom_address(&buf[4], msf, lba);
1197 return 8;
1198 }
1199
1200
do_read_toc(struct fsg_common * common,struct fsg_buffhd * bh)1201 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1202 {
1203 struct fsg_lun *curlun = &common->luns[common->lun];
1204 int msf = common->cmnd[1] & 0x02;
1205 int start_track = common->cmnd[6];
1206 u8 *buf = (u8 *) bh->buf;
1207
1208 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1209 start_track > 1) {
1210 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1211 return -EINVAL;
1212 }
1213
1214 memset(buf, 0, 20);
1215 buf[1] = (20-2); /* TOC data length */
1216 buf[2] = 1; /* First track number */
1217 buf[3] = 1; /* Last track number */
1218 buf[5] = 0x16; /* Data track, copying allowed */
1219 buf[6] = 0x01; /* Only track is number 1 */
1220 store_cdrom_address(&buf[8], msf, 0);
1221
1222 buf[13] = 0x16; /* Lead-out track is data */
1223 buf[14] = 0xAA; /* Lead-out track number */
1224 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1225
1226 return 20;
1227 }
1228
do_mode_sense(struct fsg_common * common,struct fsg_buffhd * bh)1229 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1230 {
1231 struct fsg_lun *curlun = &common->luns[common->lun];
1232 int mscmnd = common->cmnd[0];
1233 u8 *buf = (u8 *) bh->buf;
1234 u8 *buf0 = buf;
1235 int pc, page_code;
1236 int changeable_values, all_pages;
1237 int valid_page = 0;
1238 int len, limit;
1239
1240 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1241 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1242 return -EINVAL;
1243 }
1244 pc = common->cmnd[2] >> 6;
1245 page_code = common->cmnd[2] & 0x3f;
1246 if (pc == 3) {
1247 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1248 return -EINVAL;
1249 }
1250 changeable_values = (pc == 1);
1251 all_pages = (page_code == 0x3f);
1252
1253 /* Write the mode parameter header. Fixed values are: default
1254 * medium type, no cache control (DPOFUA), and no block descriptors.
1255 * The only variable value is the WriteProtect bit. We will fill in
1256 * the mode data length later. */
1257 memset(buf, 0, 8);
1258 if (mscmnd == SC_MODE_SENSE_6) {
1259 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1260 buf += 4;
1261 limit = 255;
1262 } else { /* SC_MODE_SENSE_10 */
1263 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1264 buf += 8;
1265 limit = 65535; /* Should really be FSG_BUFLEN */
1266 }
1267
1268 /* No block descriptors */
1269
1270 /* The mode pages, in numerical order. The only page we support
1271 * is the Caching page. */
1272 if (page_code == 0x08 || all_pages) {
1273 valid_page = 1;
1274 buf[0] = 0x08; /* Page code */
1275 buf[1] = 10; /* Page length */
1276 memset(buf+2, 0, 10); /* None of the fields are changeable */
1277
1278 if (!changeable_values) {
1279 buf[2] = 0x04; /* Write cache enable, */
1280 /* Read cache not disabled */
1281 /* No cache retention priorities */
1282 put_unaligned_be16(0xffff, &buf[4]);
1283 /* Don't disable prefetch */
1284 /* Minimum prefetch = 0 */
1285 put_unaligned_be16(0xffff, &buf[8]);
1286 /* Maximum prefetch */
1287 put_unaligned_be16(0xffff, &buf[10]);
1288 /* Maximum prefetch ceiling */
1289 }
1290 buf += 12;
1291 }
1292
1293 /* Check that a valid page was requested and the mode data length
1294 * isn't too long. */
1295 len = buf - buf0;
1296 if (!valid_page || len > limit) {
1297 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1298 return -EINVAL;
1299 }
1300
1301 /* Store the mode data length */
1302 if (mscmnd == SC_MODE_SENSE_6)
1303 buf0[0] = len - 1;
1304 else
1305 put_unaligned_be16(len - 2, buf0);
1306 return len;
1307 }
1308
1309
do_start_stop(struct fsg_common * common)1310 static int do_start_stop(struct fsg_common *common)
1311 {
1312 struct fsg_lun *curlun = &common->luns[common->lun];
1313
1314 if (!curlun) {
1315 return -EINVAL;
1316 } else if (!curlun->removable) {
1317 curlun->sense_data = SS_INVALID_COMMAND;
1318 return -EINVAL;
1319 }
1320
1321 return 0;
1322 }
1323
do_prevent_allow(struct fsg_common * common)1324 static int do_prevent_allow(struct fsg_common *common)
1325 {
1326 struct fsg_lun *curlun = &common->luns[common->lun];
1327 int prevent;
1328
1329 if (!curlun->removable) {
1330 curlun->sense_data = SS_INVALID_COMMAND;
1331 return -EINVAL;
1332 }
1333
1334 prevent = common->cmnd[4] & 0x01;
1335 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1336 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1337 return -EINVAL;
1338 }
1339
1340 if (curlun->prevent_medium_removal && !prevent)
1341 fsg_lun_fsync_sub(curlun);
1342 curlun->prevent_medium_removal = prevent;
1343 return 0;
1344 }
1345
1346
do_read_format_capacities(struct fsg_common * common,struct fsg_buffhd * bh)1347 static int do_read_format_capacities(struct fsg_common *common,
1348 struct fsg_buffhd *bh)
1349 {
1350 struct fsg_lun *curlun = &common->luns[common->lun];
1351 u8 *buf = (u8 *) bh->buf;
1352
1353 buf[0] = buf[1] = buf[2] = 0;
1354 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1355 buf += 4;
1356
1357 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1358 /* Number of blocks */
1359 put_unaligned_be32(512, &buf[4]); /* Block length */
1360 buf[4] = 0x02; /* Current capacity */
1361 return 12;
1362 }
1363
1364
do_mode_select(struct fsg_common * common,struct fsg_buffhd * bh)1365 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1366 {
1367 struct fsg_lun *curlun = &common->luns[common->lun];
1368
1369 /* We don't support MODE SELECT */
1370 if (curlun)
1371 curlun->sense_data = SS_INVALID_COMMAND;
1372 return -EINVAL;
1373 }
1374
1375
1376 /*-------------------------------------------------------------------------*/
1377
halt_bulk_in_endpoint(struct fsg_dev * fsg)1378 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1379 {
1380 int rc;
1381
1382 rc = fsg_set_halt(fsg, fsg->bulk_in);
1383 if (rc == -EAGAIN)
1384 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1385 while (rc != 0) {
1386 if (rc != -EAGAIN) {
1387 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1388 rc = 0;
1389 break;
1390 }
1391
1392 rc = usb_ep_set_halt(fsg->bulk_in);
1393 }
1394 return rc;
1395 }
1396
wedge_bulk_in_endpoint(struct fsg_dev * fsg)1397 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1398 {
1399 int rc;
1400
1401 DBG(fsg, "bulk-in set wedge\n");
1402 rc = 0; /* usb_ep_set_wedge(fsg->bulk_in); */
1403 if (rc == -EAGAIN)
1404 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1405 while (rc != 0) {
1406 if (rc != -EAGAIN) {
1407 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1408 rc = 0;
1409 break;
1410 }
1411 }
1412 return rc;
1413 }
1414
pad_with_zeros(struct fsg_dev * fsg)1415 static int pad_with_zeros(struct fsg_dev *fsg)
1416 {
1417 struct fsg_buffhd *bh = fsg->common->next_buffhd_to_fill;
1418 u32 nkeep = bh->inreq->length;
1419 u32 nsend;
1420 int rc;
1421
1422 bh->state = BUF_STATE_EMPTY; /* For the first iteration */
1423 fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1424 while (fsg->common->usb_amount_left > 0) {
1425
1426 /* Wait for the next buffer to be free */
1427 while (bh->state != BUF_STATE_EMPTY) {
1428 rc = sleep_thread(fsg->common);
1429 if (rc)
1430 return rc;
1431 }
1432
1433 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1434 memset(bh->buf + nkeep, 0, nsend - nkeep);
1435 bh->inreq->length = nsend;
1436 bh->inreq->zero = 0;
1437 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1438 &bh->inreq_busy, &bh->state);
1439 bh = fsg->common->next_buffhd_to_fill = bh->next;
1440 fsg->common->usb_amount_left -= nsend;
1441 nkeep = 0;
1442 }
1443 return 0;
1444 }
1445
throw_away_data(struct fsg_common * common)1446 static int throw_away_data(struct fsg_common *common)
1447 {
1448 struct fsg_buffhd *bh;
1449 u32 amount;
1450 int rc;
1451
1452 for (bh = common->next_buffhd_to_drain;
1453 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1454 bh = common->next_buffhd_to_drain) {
1455
1456 /* Throw away the data in a filled buffer */
1457 if (bh->state == BUF_STATE_FULL) {
1458 bh->state = BUF_STATE_EMPTY;
1459 common->next_buffhd_to_drain = bh->next;
1460
1461 /* A short packet or an error ends everything */
1462 if (bh->outreq->actual != bh->outreq->length ||
1463 bh->outreq->status != 0) {
1464 raise_exception(common,
1465 FSG_STATE_ABORT_BULK_OUT);
1466 return -EINTR;
1467 }
1468 continue;
1469 }
1470
1471 /* Try to submit another request if we need one */
1472 bh = common->next_buffhd_to_fill;
1473 if (bh->state == BUF_STATE_EMPTY
1474 && common->usb_amount_left > 0) {
1475 amount = min(common->usb_amount_left, FSG_BUFLEN);
1476
1477 /* amount is always divisible by 512, hence by
1478 * the bulk-out maxpacket size */
1479 bh->outreq->length = amount;
1480 bh->bulk_out_intended_length = amount;
1481 bh->outreq->short_not_ok = 1;
1482 START_TRANSFER_OR(common, bulk_out, bh->outreq,
1483 &bh->outreq_busy, &bh->state)
1484 /* Don't know what to do if
1485 * common->fsg is NULL */
1486 return -EIO;
1487 common->next_buffhd_to_fill = bh->next;
1488 common->usb_amount_left -= amount;
1489 continue;
1490 }
1491
1492 /* Otherwise wait for something to happen */
1493 rc = sleep_thread(common);
1494 if (rc)
1495 return rc;
1496 }
1497 return 0;
1498 }
1499
1500
finish_reply(struct fsg_common * common)1501 static int finish_reply(struct fsg_common *common)
1502 {
1503 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1504 int rc = 0;
1505
1506 switch (common->data_dir) {
1507 case DATA_DIR_NONE:
1508 break; /* Nothing to send */
1509
1510 /* If we don't know whether the host wants to read or write,
1511 * this must be CB or CBI with an unknown command. We mustn't
1512 * try to send or receive any data. So stall both bulk pipes
1513 * if we can and wait for a reset. */
1514 case DATA_DIR_UNKNOWN:
1515 if (!common->can_stall) {
1516 /* Nothing */
1517 } else if (fsg_is_set(common)) {
1518 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1519 rc = halt_bulk_in_endpoint(common->fsg);
1520 } else {
1521 /* Don't know what to do if common->fsg is NULL */
1522 rc = -EIO;
1523 }
1524 break;
1525
1526 /* All but the last buffer of data must have already been sent */
1527 case DATA_DIR_TO_HOST:
1528 if (common->data_size == 0) {
1529 /* Nothing to send */
1530
1531 /* If there's no residue, simply send the last buffer */
1532 } else if (common->residue == 0) {
1533 bh->inreq->zero = 0;
1534 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1535 &bh->inreq_busy, &bh->state)
1536 return -EIO;
1537 common->next_buffhd_to_fill = bh->next;
1538
1539 /* For Bulk-only, if we're allowed to stall then send the
1540 * short packet and halt the bulk-in endpoint. If we can't
1541 * stall, pad out the remaining data with 0's. */
1542 } else if (common->can_stall) {
1543 bh->inreq->zero = 1;
1544 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1545 &bh->inreq_busy, &bh->state)
1546 /* Don't know what to do if
1547 * common->fsg is NULL */
1548 rc = -EIO;
1549 common->next_buffhd_to_fill = bh->next;
1550 if (common->fsg)
1551 rc = halt_bulk_in_endpoint(common->fsg);
1552 } else if (fsg_is_set(common)) {
1553 rc = pad_with_zeros(common->fsg);
1554 } else {
1555 /* Don't know what to do if common->fsg is NULL */
1556 rc = -EIO;
1557 }
1558 break;
1559
1560 /* We have processed all we want from the data the host has sent.
1561 * There may still be outstanding bulk-out requests. */
1562 case DATA_DIR_FROM_HOST:
1563 if (common->residue == 0) {
1564 /* Nothing to receive */
1565
1566 /* Did the host stop sending unexpectedly early? */
1567 } else if (common->short_packet_received) {
1568 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1569 rc = -EINTR;
1570
1571 /* We haven't processed all the incoming data. Even though
1572 * we may be allowed to stall, doing so would cause a race.
1573 * The controller may already have ACK'ed all the remaining
1574 * bulk-out packets, in which case the host wouldn't see a
1575 * STALL. Not realizing the endpoint was halted, it wouldn't
1576 * clear the halt -- leading to problems later on. */
1577 #if 0
1578 } else if (common->can_stall) {
1579 if (fsg_is_set(common))
1580 fsg_set_halt(common->fsg,
1581 common->fsg->bulk_out);
1582 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1583 rc = -EINTR;
1584 #endif
1585
1586 /* We can't stall. Read in the excess data and throw it
1587 * all away. */
1588 } else {
1589 rc = throw_away_data(common);
1590 }
1591 break;
1592 }
1593 return rc;
1594 }
1595
1596
send_status(struct fsg_common * common)1597 static int send_status(struct fsg_common *common)
1598 {
1599 struct fsg_lun *curlun = &common->luns[common->lun];
1600 struct fsg_buffhd *bh;
1601 struct bulk_cs_wrap *csw;
1602 int rc;
1603 u8 status = USB_STATUS_PASS;
1604 u32 sd, sdinfo = 0;
1605
1606 /* Wait for the next buffer to become available */
1607 bh = common->next_buffhd_to_fill;
1608 while (bh->state != BUF_STATE_EMPTY) {
1609 rc = sleep_thread(common);
1610 if (rc)
1611 return rc;
1612 }
1613
1614 if (curlun)
1615 sd = curlun->sense_data;
1616 else if (common->bad_lun_okay)
1617 sd = SS_NO_SENSE;
1618 else
1619 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1620
1621 if (common->phase_error) {
1622 DBG(common, "sending phase-error status\n");
1623 status = USB_STATUS_PHASE_ERROR;
1624 sd = SS_INVALID_COMMAND;
1625 } else if (sd != SS_NO_SENSE) {
1626 DBG(common, "sending command-failure status\n");
1627 status = USB_STATUS_FAIL;
1628 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1629 " info x%x\n",
1630 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1631 }
1632
1633 /* Store and send the Bulk-only CSW */
1634 csw = (void *)bh->buf;
1635
1636 csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1637 csw->Tag = common->tag;
1638 csw->Residue = cpu_to_le32(common->residue);
1639 csw->Status = status;
1640
1641 bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1642 bh->inreq->zero = 0;
1643 START_TRANSFER_OR(common, bulk_in, bh->inreq,
1644 &bh->inreq_busy, &bh->state)
1645 /* Don't know what to do if common->fsg is NULL */
1646 return -EIO;
1647
1648 common->next_buffhd_to_fill = bh->next;
1649 return 0;
1650 }
1651
1652
1653 /*-------------------------------------------------------------------------*/
1654
1655 /* Check whether the command is properly formed and whether its data size
1656 * and direction agree with the values we already have. */
check_command(struct fsg_common * common,int cmnd_size,enum data_direction data_dir,unsigned int mask,int needs_medium,const char * name)1657 static int check_command(struct fsg_common *common, int cmnd_size,
1658 enum data_direction data_dir, unsigned int mask,
1659 int needs_medium, const char *name)
1660 {
1661 int i;
1662 int lun = common->cmnd[1] >> 5;
1663 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1664 char hdlen[20];
1665 struct fsg_lun *curlun;
1666
1667 hdlen[0] = 0;
1668 if (common->data_dir != DATA_DIR_UNKNOWN)
1669 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1670 common->data_size);
1671 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1672 name, cmnd_size, dirletter[(int) data_dir],
1673 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1674
1675 /* We can't reply at all until we know the correct data direction
1676 * and size. */
1677 if (common->data_size_from_cmnd == 0)
1678 data_dir = DATA_DIR_NONE;
1679 if (common->data_size < common->data_size_from_cmnd) {
1680 /* Host data size < Device data size is a phase error.
1681 * Carry out the command, but only transfer as much as
1682 * we are allowed. */
1683 common->data_size_from_cmnd = common->data_size;
1684 common->phase_error = 1;
1685 }
1686 common->residue = common->data_size;
1687 common->usb_amount_left = common->data_size;
1688
1689 /* Conflicting data directions is a phase error */
1690 if (common->data_dir != data_dir
1691 && common->data_size_from_cmnd > 0) {
1692 common->phase_error = 1;
1693 return -EINVAL;
1694 }
1695
1696 /* Verify the length of the command itself */
1697 if (cmnd_size != common->cmnd_size) {
1698
1699 /* Special case workaround: There are plenty of buggy SCSI
1700 * implementations. Many have issues with cbw->Length
1701 * field passing a wrong command size. For those cases we
1702 * always try to work around the problem by using the length
1703 * sent by the host side provided it is at least as large
1704 * as the correct command length.
1705 * Examples of such cases would be MS-Windows, which issues
1706 * REQUEST SENSE with cbw->Length == 12 where it should
1707 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1708 * REQUEST SENSE with cbw->Length == 10 where it should
1709 * be 6 as well.
1710 */
1711 if (cmnd_size <= common->cmnd_size) {
1712 DBG(common, "%s is buggy! Expected length %d "
1713 "but we got %d\n", name,
1714 cmnd_size, common->cmnd_size);
1715 cmnd_size = common->cmnd_size;
1716 } else {
1717 common->phase_error = 1;
1718 return -EINVAL;
1719 }
1720 }
1721
1722 /* Check that the LUN values are consistent */
1723 if (common->lun != lun)
1724 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1725 common->lun, lun);
1726
1727 /* Check the LUN */
1728 if (common->lun < common->nluns) {
1729 curlun = &common->luns[common->lun];
1730 if (common->cmnd[0] != SC_REQUEST_SENSE) {
1731 curlun->sense_data = SS_NO_SENSE;
1732 curlun->info_valid = 0;
1733 }
1734 } else {
1735 curlun = NULL;
1736 common->bad_lun_okay = 0;
1737
1738 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
1739 * to use unsupported LUNs; all others may not. */
1740 if (common->cmnd[0] != SC_INQUIRY &&
1741 common->cmnd[0] != SC_REQUEST_SENSE) {
1742 DBG(common, "unsupported LUN %d\n", common->lun);
1743 return -EINVAL;
1744 }
1745 }
1746 #if 0
1747 /* If a unit attention condition exists, only INQUIRY and
1748 * REQUEST SENSE commands are allowed; anything else must fail. */
1749 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1750 common->cmnd[0] != SC_INQUIRY &&
1751 common->cmnd[0] != SC_REQUEST_SENSE) {
1752 curlun->sense_data = curlun->unit_attention_data;
1753 curlun->unit_attention_data = SS_NO_SENSE;
1754 return -EINVAL;
1755 }
1756 #endif
1757 /* Check that only command bytes listed in the mask are non-zero */
1758 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1759 for (i = 1; i < cmnd_size; ++i) {
1760 if (common->cmnd[i] && !(mask & (1 << i))) {
1761 if (curlun)
1762 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1763 return -EINVAL;
1764 }
1765 }
1766
1767 return 0;
1768 }
1769
1770
do_scsi_command(struct fsg_common * common)1771 static int do_scsi_command(struct fsg_common *common)
1772 {
1773 struct fsg_buffhd *bh;
1774 int rc;
1775 int reply = -EINVAL;
1776 int i;
1777 static char unknown[16];
1778 struct fsg_lun *curlun = &common->luns[common->lun];
1779
1780 dump_cdb(common);
1781
1782 /* Wait for the next buffer to become available for data or status */
1783 bh = common->next_buffhd_to_fill;
1784 common->next_buffhd_to_drain = bh;
1785 while (bh->state != BUF_STATE_EMPTY) {
1786 rc = sleep_thread(common);
1787 if (rc)
1788 return rc;
1789 }
1790 common->phase_error = 0;
1791 common->short_packet_received = 0;
1792
1793 down_read(&common->filesem); /* We're using the backing file */
1794 switch (common->cmnd[0]) {
1795
1796 case SC_INQUIRY:
1797 common->data_size_from_cmnd = common->cmnd[4];
1798 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1799 (1<<4), 0,
1800 "INQUIRY");
1801 if (reply == 0)
1802 reply = do_inquiry(common, bh);
1803 break;
1804
1805 case SC_MODE_SELECT_6:
1806 common->data_size_from_cmnd = common->cmnd[4];
1807 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1808 (1<<1) | (1<<4), 0,
1809 "MODE SELECT(6)");
1810 if (reply == 0)
1811 reply = do_mode_select(common, bh);
1812 break;
1813
1814 case SC_MODE_SELECT_10:
1815 common->data_size_from_cmnd =
1816 get_unaligned_be16(&common->cmnd[7]);
1817 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1818 (1<<1) | (3<<7), 0,
1819 "MODE SELECT(10)");
1820 if (reply == 0)
1821 reply = do_mode_select(common, bh);
1822 break;
1823
1824 case SC_MODE_SENSE_6:
1825 common->data_size_from_cmnd = common->cmnd[4];
1826 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1827 (1<<1) | (1<<2) | (1<<4), 0,
1828 "MODE SENSE(6)");
1829 if (reply == 0)
1830 reply = do_mode_sense(common, bh);
1831 break;
1832
1833 case SC_MODE_SENSE_10:
1834 common->data_size_from_cmnd =
1835 get_unaligned_be16(&common->cmnd[7]);
1836 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1837 (1<<1) | (1<<2) | (3<<7), 0,
1838 "MODE SENSE(10)");
1839 if (reply == 0)
1840 reply = do_mode_sense(common, bh);
1841 break;
1842
1843 case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
1844 common->data_size_from_cmnd = 0;
1845 reply = check_command(common, 6, DATA_DIR_NONE,
1846 (1<<4), 0,
1847 "PREVENT-ALLOW MEDIUM REMOVAL");
1848 if (reply == 0)
1849 reply = do_prevent_allow(common);
1850 break;
1851
1852 case SC_READ_6:
1853 i = common->cmnd[4];
1854 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1855 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1856 (7<<1) | (1<<4), 1,
1857 "READ(6)");
1858 if (reply == 0)
1859 reply = do_read(common);
1860 break;
1861
1862 case SC_READ_10:
1863 common->data_size_from_cmnd =
1864 get_unaligned_be16(&common->cmnd[7]) << 9;
1865 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1866 (1<<1) | (0xf<<2) | (3<<7), 1,
1867 "READ(10)");
1868 if (reply == 0)
1869 reply = do_read(common);
1870 break;
1871
1872 case SC_READ_12:
1873 common->data_size_from_cmnd =
1874 get_unaligned_be32(&common->cmnd[6]) << 9;
1875 reply = check_command(common, 12, DATA_DIR_TO_HOST,
1876 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1877 "READ(12)");
1878 if (reply == 0)
1879 reply = do_read(common);
1880 break;
1881
1882 case SC_READ_CAPACITY:
1883 common->data_size_from_cmnd = 8;
1884 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1885 (0xf<<2) | (1<<8), 1,
1886 "READ CAPACITY");
1887 if (reply == 0)
1888 reply = do_read_capacity(common, bh);
1889 break;
1890
1891 case SC_READ_HEADER:
1892 if (!common->luns[common->lun].cdrom)
1893 goto unknown_cmnd;
1894 common->data_size_from_cmnd =
1895 get_unaligned_be16(&common->cmnd[7]);
1896 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1897 (3<<7) | (0x1f<<1), 1,
1898 "READ HEADER");
1899 if (reply == 0)
1900 reply = do_read_header(common, bh);
1901 break;
1902
1903 case SC_READ_TOC:
1904 if (!common->luns[common->lun].cdrom)
1905 goto unknown_cmnd;
1906 common->data_size_from_cmnd =
1907 get_unaligned_be16(&common->cmnd[7]);
1908 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1909 (7<<6) | (1<<1), 1,
1910 "READ TOC");
1911 if (reply == 0)
1912 reply = do_read_toc(common, bh);
1913 break;
1914
1915 case SC_READ_FORMAT_CAPACITIES:
1916 common->data_size_from_cmnd =
1917 get_unaligned_be16(&common->cmnd[7]);
1918 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1919 (3<<7), 1,
1920 "READ FORMAT CAPACITIES");
1921 if (reply == 0)
1922 reply = do_read_format_capacities(common, bh);
1923 break;
1924
1925 case SC_REQUEST_SENSE:
1926 common->data_size_from_cmnd = common->cmnd[4];
1927 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1928 (1<<4), 0,
1929 "REQUEST SENSE");
1930 if (reply == 0)
1931 reply = do_request_sense(common, bh);
1932 break;
1933
1934 case SC_START_STOP_UNIT:
1935 common->data_size_from_cmnd = 0;
1936 reply = check_command(common, 6, DATA_DIR_NONE,
1937 (1<<1) | (1<<4), 0,
1938 "START-STOP UNIT");
1939 if (reply == 0)
1940 reply = do_start_stop(common);
1941 break;
1942
1943 case SC_SYNCHRONIZE_CACHE:
1944 common->data_size_from_cmnd = 0;
1945 reply = check_command(common, 10, DATA_DIR_NONE,
1946 (0xf<<2) | (3<<7), 1,
1947 "SYNCHRONIZE CACHE");
1948 if (reply == 0)
1949 reply = do_synchronize_cache(common);
1950 break;
1951
1952 case SC_TEST_UNIT_READY:
1953 common->data_size_from_cmnd = 0;
1954 reply = check_command(common, 6, DATA_DIR_NONE,
1955 0, 1,
1956 "TEST UNIT READY");
1957 break;
1958
1959 /* Although optional, this command is used by MS-Windows. We
1960 * support a minimal version: BytChk must be 0. */
1961 case SC_VERIFY:
1962 common->data_size_from_cmnd = 0;
1963 reply = check_command(common, 10, DATA_DIR_NONE,
1964 (1<<1) | (0xf<<2) | (3<<7), 1,
1965 "VERIFY");
1966 if (reply == 0)
1967 reply = do_verify(common);
1968 break;
1969
1970 case SC_WRITE_6:
1971 i = common->cmnd[4];
1972 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1973 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1974 (7<<1) | (1<<4), 1,
1975 "WRITE(6)");
1976 if (reply == 0)
1977 reply = do_write(common);
1978 break;
1979
1980 case SC_WRITE_10:
1981 common->data_size_from_cmnd =
1982 get_unaligned_be16(&common->cmnd[7]) << 9;
1983 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1984 (1<<1) | (0xf<<2) | (3<<7), 1,
1985 "WRITE(10)");
1986 if (reply == 0)
1987 reply = do_write(common);
1988 break;
1989
1990 case SC_WRITE_12:
1991 common->data_size_from_cmnd =
1992 get_unaligned_be32(&common->cmnd[6]) << 9;
1993 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
1994 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1995 "WRITE(12)");
1996 if (reply == 0)
1997 reply = do_write(common);
1998 break;
1999
2000 /* Some mandatory commands that we recognize but don't implement.
2001 * They don't mean much in this setting. It's left as an exercise
2002 * for anyone interested to implement RESERVE and RELEASE in terms
2003 * of Posix locks. */
2004 case SC_FORMAT_UNIT:
2005 case SC_RELEASE:
2006 case SC_RESERVE:
2007 case SC_SEND_DIAGNOSTIC:
2008 /* Fall through */
2009
2010 default:
2011 unknown_cmnd:
2012 common->data_size_from_cmnd = 0;
2013 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2014 reply = check_command(common, common->cmnd_size,
2015 DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2016 if (reply == 0) {
2017 curlun->sense_data = SS_INVALID_COMMAND;
2018 reply = -EINVAL;
2019 }
2020 break;
2021 }
2022 up_read(&common->filesem);
2023
2024 if (reply == -EINTR)
2025 return -EINTR;
2026
2027 /* Set up the single reply buffer for finish_reply() */
2028 if (reply == -EINVAL)
2029 reply = 0; /* Error reply length */
2030 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2031 reply = min((u32) reply, common->data_size_from_cmnd);
2032 bh->inreq->length = reply;
2033 bh->state = BUF_STATE_FULL;
2034 common->residue -= reply;
2035 } /* Otherwise it's already set */
2036
2037 return 0;
2038 }
2039
2040 /*-------------------------------------------------------------------------*/
2041
received_cbw(struct fsg_dev * fsg,struct fsg_buffhd * bh)2042 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2043 {
2044 struct usb_request *req = bh->outreq;
2045 struct fsg_bulk_cb_wrap *cbw = req->buf;
2046 struct fsg_common *common = fsg->common;
2047
2048 /* Was this a real packet? Should it be ignored? */
2049 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2050 return -EINVAL;
2051
2052 /* Is the CBW valid? */
2053 if (req->actual != USB_BULK_CB_WRAP_LEN ||
2054 cbw->Signature != cpu_to_le32(
2055 USB_BULK_CB_SIG)) {
2056 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2057 req->actual,
2058 le32_to_cpu(cbw->Signature));
2059
2060 /* The Bulk-only spec says we MUST stall the IN endpoint
2061 * (6.6.1), so it's unavoidable. It also says we must
2062 * retain this state until the next reset, but there's
2063 * no way to tell the controller driver it should ignore
2064 * Clear-Feature(HALT) requests.
2065 *
2066 * We aren't required to halt the OUT endpoint; instead
2067 * we can simply accept and discard any data received
2068 * until the next reset. */
2069 wedge_bulk_in_endpoint(fsg);
2070 generic_set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2071 return -EINVAL;
2072 }
2073
2074 /* Is the CBW meaningful? */
2075 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2076 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2077 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2078 "cmdlen %u\n",
2079 cbw->Lun, cbw->Flags, cbw->Length);
2080
2081 /* We can do anything we want here, so let's stall the
2082 * bulk pipes if we are allowed to. */
2083 if (common->can_stall) {
2084 fsg_set_halt(fsg, fsg->bulk_out);
2085 halt_bulk_in_endpoint(fsg);
2086 }
2087 return -EINVAL;
2088 }
2089
2090 /* Save the command for later */
2091 common->cmnd_size = cbw->Length;
2092 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2093 if (cbw->Flags & USB_BULK_IN_FLAG)
2094 common->data_dir = DATA_DIR_TO_HOST;
2095 else
2096 common->data_dir = DATA_DIR_FROM_HOST;
2097 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2098 if (common->data_size == 0)
2099 common->data_dir = DATA_DIR_NONE;
2100 common->lun = cbw->Lun;
2101 common->tag = cbw->Tag;
2102 return 0;
2103 }
2104
2105
get_next_command(struct fsg_common * common)2106 static int get_next_command(struct fsg_common *common)
2107 {
2108 struct fsg_buffhd *bh;
2109 int rc = 0;
2110
2111 /* Wait for the next buffer to become available */
2112 bh = common->next_buffhd_to_fill;
2113 while (bh->state != BUF_STATE_EMPTY) {
2114 rc = sleep_thread(common);
2115 if (rc)
2116 return rc;
2117 }
2118
2119 /* Queue a request to read a Bulk-only CBW */
2120 set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2121 bh->outreq->short_not_ok = 1;
2122 START_TRANSFER_OR(common, bulk_out, bh->outreq,
2123 &bh->outreq_busy, &bh->state)
2124 /* Don't know what to do if common->fsg is NULL */
2125 return -EIO;
2126
2127 /* We will drain the buffer in software, which means we
2128 * can reuse it for the next filling. No need to advance
2129 * next_buffhd_to_fill. */
2130
2131 /* Wait for the CBW to arrive */
2132 while (bh->state != BUF_STATE_FULL) {
2133 rc = sleep_thread(common);
2134 if (rc)
2135 return rc;
2136 }
2137
2138 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2139 bh->state = BUF_STATE_EMPTY;
2140
2141 return rc;
2142 }
2143
2144
2145 /*-------------------------------------------------------------------------*/
2146
enable_endpoint(struct fsg_common * common,struct usb_ep * ep,const struct usb_endpoint_descriptor * d)2147 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2148 const struct usb_endpoint_descriptor *d)
2149 {
2150 int rc;
2151
2152 ep->driver_data = common;
2153 rc = usb_ep_enable(ep, d);
2154 if (rc)
2155 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2156 return rc;
2157 }
2158
alloc_request(struct fsg_common * common,struct usb_ep * ep,struct usb_request ** preq)2159 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2160 struct usb_request **preq)
2161 {
2162 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2163 if (*preq)
2164 return 0;
2165 ERROR(common, "can't allocate request for %s\n", ep->name);
2166 return -ENOMEM;
2167 }
2168
2169 /* Reset interface setting and re-init endpoint state (toggle etc). */
do_set_interface(struct fsg_common * common,struct fsg_dev * new_fsg)2170 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2171 {
2172 const struct usb_endpoint_descriptor *d;
2173 struct fsg_dev *fsg;
2174 int i, rc = 0;
2175
2176 if (common->running)
2177 DBG(common, "reset interface\n");
2178
2179 reset:
2180 /* Deallocate the requests */
2181 if (common->fsg) {
2182 fsg = common->fsg;
2183
2184 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2185 struct fsg_buffhd *bh = &common->buffhds[i];
2186
2187 if (bh->inreq) {
2188 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2189 bh->inreq = NULL;
2190 }
2191 if (bh->outreq) {
2192 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2193 bh->outreq = NULL;
2194 }
2195 }
2196
2197 /* Disable the endpoints */
2198 if (fsg->bulk_in_enabled) {
2199 usb_ep_disable(fsg->bulk_in);
2200 fsg->bulk_in_enabled = 0;
2201 }
2202 if (fsg->bulk_out_enabled) {
2203 usb_ep_disable(fsg->bulk_out);
2204 fsg->bulk_out_enabled = 0;
2205 }
2206
2207 common->fsg = NULL;
2208 /* wake_up(&common->fsg_wait); */
2209 }
2210
2211 common->running = 0;
2212 if (!new_fsg || rc)
2213 return rc;
2214
2215 common->fsg = new_fsg;
2216 fsg = common->fsg;
2217
2218 /* Enable the endpoints */
2219 d = fsg_ep_desc(common->gadget,
2220 &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2221 rc = enable_endpoint(common, fsg->bulk_in, d);
2222 if (rc)
2223 goto reset;
2224 fsg->bulk_in_enabled = 1;
2225
2226 d = fsg_ep_desc(common->gadget,
2227 &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2228 rc = enable_endpoint(common, fsg->bulk_out, d);
2229 if (rc)
2230 goto reset;
2231 fsg->bulk_out_enabled = 1;
2232 common->bulk_out_maxpacket =
2233 le16_to_cpu(get_unaligned(&d->wMaxPacketSize));
2234 generic_clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2235
2236 /* Allocate the requests */
2237 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2238 struct fsg_buffhd *bh = &common->buffhds[i];
2239
2240 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2241 if (rc)
2242 goto reset;
2243 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2244 if (rc)
2245 goto reset;
2246 bh->inreq->buf = bh->outreq->buf = bh->buf;
2247 bh->inreq->context = bh->outreq->context = bh;
2248 bh->inreq->complete = bulk_in_complete;
2249 bh->outreq->complete = bulk_out_complete;
2250 }
2251
2252 common->running = 1;
2253
2254 return rc;
2255 }
2256
2257
2258 /****************************** ALT CONFIGS ******************************/
2259
2260
fsg_set_alt(struct usb_function * f,unsigned intf,unsigned alt)2261 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2262 {
2263 struct fsg_dev *fsg = fsg_from_func(f);
2264 fsg->common->new_fsg = fsg;
2265 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2266 return 0;
2267 }
2268
fsg_disable(struct usb_function * f)2269 static void fsg_disable(struct usb_function *f)
2270 {
2271 struct fsg_dev *fsg = fsg_from_func(f);
2272 fsg->common->new_fsg = NULL;
2273 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2274 }
2275
2276 /*-------------------------------------------------------------------------*/
2277
handle_exception(struct fsg_common * common)2278 static void handle_exception(struct fsg_common *common)
2279 {
2280 int i;
2281 struct fsg_buffhd *bh;
2282 enum fsg_state old_state;
2283 struct fsg_lun *curlun;
2284 unsigned int exception_req_tag;
2285
2286 /* Cancel all the pending transfers */
2287 if (common->fsg) {
2288 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2289 bh = &common->buffhds[i];
2290 if (bh->inreq_busy)
2291 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2292 if (bh->outreq_busy)
2293 usb_ep_dequeue(common->fsg->bulk_out,
2294 bh->outreq);
2295 }
2296
2297 /* Wait until everything is idle */
2298 for (;;) {
2299 int num_active = 0;
2300 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2301 bh = &common->buffhds[i];
2302 num_active += bh->inreq_busy + bh->outreq_busy;
2303 }
2304 if (num_active == 0)
2305 break;
2306 if (sleep_thread(common))
2307 return;
2308 }
2309
2310 /* Clear out the controller's fifos */
2311 if (common->fsg->bulk_in_enabled)
2312 usb_ep_fifo_flush(common->fsg->bulk_in);
2313 if (common->fsg->bulk_out_enabled)
2314 usb_ep_fifo_flush(common->fsg->bulk_out);
2315 }
2316
2317 /* Reset the I/O buffer states and pointers, the SCSI
2318 * state, and the exception. Then invoke the handler. */
2319
2320 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2321 bh = &common->buffhds[i];
2322 bh->state = BUF_STATE_EMPTY;
2323 }
2324 common->next_buffhd_to_fill = &common->buffhds[0];
2325 common->next_buffhd_to_drain = &common->buffhds[0];
2326 exception_req_tag = common->exception_req_tag;
2327 old_state = common->state;
2328
2329 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2330 common->state = FSG_STATE_STATUS_PHASE;
2331 else {
2332 for (i = 0; i < common->nluns; ++i) {
2333 curlun = &common->luns[i];
2334 curlun->sense_data = SS_NO_SENSE;
2335 curlun->info_valid = 0;
2336 }
2337 common->state = FSG_STATE_IDLE;
2338 }
2339
2340 /* Carry out any extra actions required for the exception */
2341 switch (old_state) {
2342 case FSG_STATE_ABORT_BULK_OUT:
2343 send_status(common);
2344
2345 if (common->state == FSG_STATE_STATUS_PHASE)
2346 common->state = FSG_STATE_IDLE;
2347 break;
2348
2349 case FSG_STATE_RESET:
2350 /* In case we were forced against our will to halt a
2351 * bulk endpoint, clear the halt now. (The SuperH UDC
2352 * requires this.) */
2353 if (!fsg_is_set(common))
2354 break;
2355 if (test_and_clear_bit(IGNORE_BULK_OUT,
2356 &common->fsg->atomic_bitflags))
2357 usb_ep_clear_halt(common->fsg->bulk_in);
2358
2359 if (common->ep0_req_tag == exception_req_tag)
2360 ep0_queue(common); /* Complete the status stage */
2361
2362 break;
2363
2364 case FSG_STATE_CONFIG_CHANGE:
2365 do_set_interface(common, common->new_fsg);
2366 break;
2367
2368 case FSG_STATE_EXIT:
2369 case FSG_STATE_TERMINATED:
2370 do_set_interface(common, NULL); /* Free resources */
2371 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2372 break;
2373
2374 case FSG_STATE_INTERFACE_CHANGE:
2375 case FSG_STATE_DISCONNECT:
2376 case FSG_STATE_COMMAND_PHASE:
2377 case FSG_STATE_DATA_PHASE:
2378 case FSG_STATE_STATUS_PHASE:
2379 case FSG_STATE_IDLE:
2380 break;
2381 }
2382 }
2383
2384 /*-------------------------------------------------------------------------*/
2385
fsg_main_thread(void * common_)2386 int fsg_main_thread(void *common_)
2387 {
2388 int ret;
2389 struct fsg_common *common = the_fsg_common;
2390 /* The main loop */
2391 do {
2392 if (exception_in_progress(common)) {
2393 handle_exception(common);
2394 continue;
2395 }
2396
2397 if (!common->running) {
2398 ret = sleep_thread(common);
2399 if (ret)
2400 return ret;
2401
2402 continue;
2403 }
2404
2405 ret = get_next_command(common);
2406 if (ret)
2407 return ret;
2408
2409 if (!exception_in_progress(common))
2410 common->state = FSG_STATE_DATA_PHASE;
2411
2412 if (do_scsi_command(common) || finish_reply(common))
2413 continue;
2414
2415 if (!exception_in_progress(common))
2416 common->state = FSG_STATE_STATUS_PHASE;
2417
2418 if (send_status(common))
2419 continue;
2420
2421 if (!exception_in_progress(common))
2422 common->state = FSG_STATE_IDLE;
2423 } while (0);
2424
2425 common->thread_task = NULL;
2426
2427 return 0;
2428 }
2429
2430 static void fsg_common_release(struct kref *ref);
2431
fsg_common_init(struct fsg_common * common,struct usb_composite_dev * cdev)2432 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2433 struct usb_composite_dev *cdev)
2434 {
2435 struct usb_gadget *gadget = cdev->gadget;
2436 struct fsg_buffhd *bh;
2437 struct fsg_lun *curlun;
2438 int nluns, i, rc;
2439
2440 /* Find out how many LUNs there should be */
2441 nluns = ums_count;
2442 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2443 printf("invalid number of LUNs: %u\n", nluns);
2444 return ERR_PTR(-EINVAL);
2445 }
2446
2447 /* Allocate? */
2448 if (!common) {
2449 common = calloc(sizeof(*common), 1);
2450 if (!common)
2451 return ERR_PTR(-ENOMEM);
2452 common->free_storage_on_release = 1;
2453 } else {
2454 memset(common, 0, sizeof(*common));
2455 common->free_storage_on_release = 0;
2456 }
2457
2458 common->ops = NULL;
2459 common->private_data = NULL;
2460
2461 common->gadget = gadget;
2462 common->ep0 = gadget->ep0;
2463 common->ep0req = cdev->req;
2464
2465 /* Maybe allocate device-global string IDs, and patch descriptors */
2466 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2467 rc = usb_string_id(cdev);
2468 if (unlikely(rc < 0))
2469 goto error_release;
2470 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2471 fsg_intf_desc.iInterface = rc;
2472 }
2473
2474 /* Create the LUNs, open their backing files, and register the
2475 * LUN devices in sysfs. */
2476 curlun = calloc(nluns, sizeof *curlun);
2477 if (!curlun) {
2478 rc = -ENOMEM;
2479 goto error_release;
2480 }
2481 common->nluns = nluns;
2482
2483 for (i = 0; i < nluns; i++) {
2484 common->luns[i].removable = 1;
2485
2486 rc = fsg_lun_open(&common->luns[i], ums[i].num_sectors, "");
2487 if (rc)
2488 goto error_luns;
2489 }
2490 common->lun = 0;
2491
2492 /* Data buffers cyclic list */
2493 bh = common->buffhds;
2494
2495 i = FSG_NUM_BUFFERS;
2496 goto buffhds_first_it;
2497 do {
2498 bh->next = bh + 1;
2499 ++bh;
2500 buffhds_first_it:
2501 bh->inreq_busy = 0;
2502 bh->outreq_busy = 0;
2503 bh->buf = memalign(CONFIG_SYS_CACHELINE_SIZE, FSG_BUFLEN);
2504 if (unlikely(!bh->buf)) {
2505 rc = -ENOMEM;
2506 goto error_release;
2507 }
2508 } while (--i);
2509 bh->next = common->buffhds;
2510
2511 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2512 "%-8s%-16s%04x",
2513 "Linux ",
2514 "File-Store Gadget",
2515 0xffff);
2516
2517 /* Some peripheral controllers are known not to be able to
2518 * halt bulk endpoints correctly. If one of them is present,
2519 * disable stalls.
2520 */
2521
2522 /* Tell the thread to start working */
2523 common->thread_task =
2524 kthread_create(fsg_main_thread, common,
2525 OR(cfg->thread_name, "file-storage"));
2526 if (IS_ERR(common->thread_task)) {
2527 rc = PTR_ERR(common->thread_task);
2528 goto error_release;
2529 }
2530
2531 #undef OR
2532 /* Information */
2533 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2534 INFO(common, "Number of LUNs=%d\n", common->nluns);
2535
2536 return common;
2537
2538 error_luns:
2539 common->nluns = i + 1;
2540 error_release:
2541 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2542 /* Call fsg_common_release() directly, ref might be not
2543 * initialised */
2544 fsg_common_release(&common->ref);
2545 return ERR_PTR(rc);
2546 }
2547
fsg_common_release(struct kref * ref)2548 static void fsg_common_release(struct kref *ref)
2549 {
2550 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2551
2552 /* If the thread isn't already dead, tell it to exit now */
2553 if (common->state != FSG_STATE_TERMINATED) {
2554 raise_exception(common, FSG_STATE_EXIT);
2555 wait_for_completion(&common->thread_notifier);
2556 }
2557
2558 if (likely(common->luns)) {
2559 struct fsg_lun *lun = common->luns;
2560 unsigned i = common->nluns;
2561
2562 /* In error recovery common->nluns may be zero. */
2563 for (; i; --i, ++lun)
2564 fsg_lun_close(lun);
2565
2566 kfree(common->luns);
2567 }
2568
2569 {
2570 struct fsg_buffhd *bh = common->buffhds;
2571 unsigned i = FSG_NUM_BUFFERS;
2572 do {
2573 kfree(bh->buf);
2574 } while (++bh, --i);
2575 }
2576
2577 if (common->free_storage_on_release)
2578 kfree(common);
2579 }
2580
2581
2582 /*-------------------------------------------------------------------------*/
2583
2584 /**
2585 * usb_copy_descriptors - copy a vector of USB descriptors
2586 * @src: null-terminated vector to copy
2587 * Context: initialization code, which may sleep
2588 *
2589 * This makes a copy of a vector of USB descriptors. Its primary use
2590 * is to support usb_function objects which can have multiple copies,
2591 * each needing different descriptors. Functions may have static
2592 * tables of descriptors, which are used as templates and customized
2593 * with identifiers (for interfaces, strings, endpoints, and more)
2594 * as needed by a given function instance.
2595 */
2596 struct usb_descriptor_header **
usb_copy_descriptors(struct usb_descriptor_header ** src)2597 usb_copy_descriptors(struct usb_descriptor_header **src)
2598 {
2599 struct usb_descriptor_header **tmp;
2600 unsigned bytes;
2601 unsigned n_desc;
2602 void *mem;
2603 struct usb_descriptor_header **ret;
2604
2605 /* count descriptors and their sizes; then add vector size */
2606 for (bytes = 0, n_desc = 0, tmp = src; *tmp; tmp++, n_desc++)
2607 bytes += (*tmp)->bLength;
2608 bytes += (n_desc + 1) * sizeof(*tmp);
2609
2610 mem = memalign(CONFIG_SYS_CACHELINE_SIZE, bytes);
2611 if (!mem)
2612 return NULL;
2613
2614 /* fill in pointers starting at "tmp",
2615 * to descriptors copied starting at "mem";
2616 * and return "ret"
2617 */
2618 tmp = mem;
2619 ret = mem;
2620 mem += (n_desc + 1) * sizeof(*tmp);
2621 while (*src) {
2622 memcpy(mem, *src, (*src)->bLength);
2623 *tmp = mem;
2624 tmp++;
2625 mem += (*src)->bLength;
2626 src++;
2627 }
2628 *tmp = NULL;
2629
2630 return ret;
2631 }
2632
fsg_unbind(struct usb_configuration * c,struct usb_function * f)2633 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2634 {
2635 struct fsg_dev *fsg = fsg_from_func(f);
2636
2637 DBG(fsg, "unbind\n");
2638 if (fsg->common->fsg == fsg) {
2639 fsg->common->new_fsg = NULL;
2640 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2641 }
2642
2643 free(fsg->function.descriptors);
2644 free(fsg->function.hs_descriptors);
2645 kfree(fsg);
2646 }
2647
fsg_bind(struct usb_configuration * c,struct usb_function * f)2648 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2649 {
2650 struct fsg_dev *fsg = fsg_from_func(f);
2651 struct usb_gadget *gadget = c->cdev->gadget;
2652 int i;
2653 struct usb_ep *ep;
2654 fsg->gadget = gadget;
2655
2656 /* New interface */
2657 i = usb_interface_id(c, f);
2658 if (i < 0)
2659 return i;
2660 fsg_intf_desc.bInterfaceNumber = i;
2661 fsg->interface_number = i;
2662
2663 /* Find all the endpoints we will use */
2664 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2665 if (!ep)
2666 goto autoconf_fail;
2667 ep->driver_data = fsg->common; /* claim the endpoint */
2668 fsg->bulk_in = ep;
2669
2670 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2671 if (!ep)
2672 goto autoconf_fail;
2673 ep->driver_data = fsg->common; /* claim the endpoint */
2674 fsg->bulk_out = ep;
2675
2676 /* Copy descriptors */
2677 f->descriptors = usb_copy_descriptors(fsg_fs_function);
2678 if (unlikely(!f->descriptors))
2679 return -ENOMEM;
2680
2681 if (gadget_is_dualspeed(gadget)) {
2682 /* Assume endpoint addresses are the same for both speeds */
2683 fsg_hs_bulk_in_desc.bEndpointAddress =
2684 fsg_fs_bulk_in_desc.bEndpointAddress;
2685 fsg_hs_bulk_out_desc.bEndpointAddress =
2686 fsg_fs_bulk_out_desc.bEndpointAddress;
2687 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
2688 if (unlikely(!f->hs_descriptors)) {
2689 free(f->descriptors);
2690 return -ENOMEM;
2691 }
2692 }
2693 return 0;
2694
2695 autoconf_fail:
2696 ERROR(fsg, "unable to autoconfigure all endpoints\n");
2697 return -ENOTSUPP;
2698 }
2699
2700
2701 /****************************** ADD FUNCTION ******************************/
2702
2703 static struct usb_gadget_strings *fsg_strings_array[] = {
2704 &fsg_stringtab,
2705 NULL,
2706 };
2707
fsg_bind_config(struct usb_composite_dev * cdev,struct usb_configuration * c,struct fsg_common * common)2708 static int fsg_bind_config(struct usb_composite_dev *cdev,
2709 struct usb_configuration *c,
2710 struct fsg_common *common)
2711 {
2712 struct fsg_dev *fsg;
2713 int rc;
2714
2715 fsg = calloc(1, sizeof *fsg);
2716 if (!fsg)
2717 return -ENOMEM;
2718 fsg->function.name = FSG_DRIVER_DESC;
2719 fsg->function.strings = fsg_strings_array;
2720 fsg->function.bind = fsg_bind;
2721 fsg->function.unbind = fsg_unbind;
2722 fsg->function.setup = fsg_setup;
2723 fsg->function.set_alt = fsg_set_alt;
2724 fsg->function.disable = fsg_disable;
2725
2726 fsg->common = common;
2727 common->fsg = fsg;
2728 /* Our caller holds a reference to common structure so we
2729 * don't have to be worry about it being freed until we return
2730 * from this function. So instead of incrementing counter now
2731 * and decrement in error recovery we increment it only when
2732 * call to usb_add_function() was successful. */
2733
2734 rc = usb_add_function(c, &fsg->function);
2735
2736 if (rc)
2737 kfree(fsg);
2738
2739 return rc;
2740 }
2741
fsg_add(struct usb_configuration * c)2742 int fsg_add(struct usb_configuration *c)
2743 {
2744 struct fsg_common *fsg_common;
2745
2746 fsg_common = fsg_common_init(NULL, c->cdev);
2747
2748 fsg_common->vendor_name = 0;
2749 fsg_common->product_name = 0;
2750 fsg_common->release = 0xffff;
2751
2752 fsg_common->ops = NULL;
2753 fsg_common->private_data = NULL;
2754
2755 the_fsg_common = fsg_common;
2756
2757 return fsg_bind_config(c->cdev, c, fsg_common);
2758 }
2759
fsg_init(struct ums * ums_devs,int count)2760 int fsg_init(struct ums *ums_devs, int count)
2761 {
2762 ums = ums_devs;
2763 ums_count = count;
2764
2765 return 0;
2766 }
2767
2768 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_ums, fsg_add);
2769