usb: f_mass_storage: sleep_thread: retrigger watchdog
[karo-tx-uboot.git] / drivers / usb / gadget / f_mass_storage.c
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  * SPDX-License-Identifier: GPL-2.0+    BSD-3-Clause
10  */
11
12 /*
13  * The Mass Storage Function acts as a USB Mass Storage device,
14  * appearing to the host as a disk drive or as a CD-ROM drive.  In
15  * addition to providing an example of a genuinely useful composite
16  * function for a USB device, it also illustrates a technique of
17  * double-buffering for increased throughput.
18  *
19  * Function supports multiple logical units (LUNs).  Backing storage
20  * for each LUN is provided by a regular file or a block device.
21  * Access for each LUN can be limited to read-only.  Moreover, the
22  * function can indicate that LUN is removable and/or CD-ROM.  (The
23  * later implies read-only access.)
24  *
25  * MSF is configured by specifying a fsg_config structure.  It has the
26  * following fields:
27  *
28  *      nluns           Number of LUNs function have (anywhere from 1
29  *                              to FSG_MAX_LUNS which is 8).
30  *      luns            An array of LUN configuration values.  This
31  *                              should be filled for each LUN that
32  *                              function will include (ie. for "nluns"
33  *                              LUNs).  Each element of the array has
34  *                              the following fields:
35  *      ->filename      The path to the backing file for the LUN.
36  *                              Required if LUN is not marked as
37  *                              removable.
38  *      ->ro            Flag specifying access to the LUN shall be
39  *                              read-only.  This is implied if CD-ROM
40  *                              emulation is enabled as well as when
41  *                              it was impossible to open "filename"
42  *                              in R/W mode.
43  *      ->removable     Flag specifying that LUN shall be indicated as
44  *                              being removable.
45  *      ->cdrom         Flag specifying that LUN shall be reported as
46  *                              being a CD-ROM.
47  *
48  *      lun_name_format A printf-like format for names of the LUN
49  *                              devices.  This determines how the
50  *                              directory in sysfs will be named.
51  *                              Unless you are using several MSFs in
52  *                              a single gadget (as opposed to single
53  *                              MSF in many configurations) you may
54  *                              leave it as NULL (in which case
55  *                              "lun%d" will be used).  In the format
56  *                              you can use "%d" to index LUNs for
57  *                              MSF's with more than one LUN.  (Beware
58  *                              that there is only one integer given
59  *                              as an argument for the format and
60  *                              specifying invalid format may cause
61  *                              unspecified behaviour.)
62  *      thread_name     Name of the kernel thread process used by the
63  *                              MSF.  You can safely set it to NULL
64  *                              (in which case default "file-storage"
65  *                              will be used).
66  *
67  *      vendor_name
68  *      product_name
69  *      release         Information used as a reply to INQUIRY
70  *                              request.  To use default set to NULL,
71  *                              NULL, 0xffff respectively.  The first
72  *                              field should be 8 and the second 16
73  *                              characters or less.
74  *
75  *      can_stall       Set to permit function to halt bulk endpoints.
76  *                              Disabled on some USB devices known not
77  *                              to work correctly.  You should set it
78  *                              to true.
79  *
80  * If "removable" is not set for a LUN then a backing file must be
81  * specified.  If it is set, then NULL filename means the LUN's medium
82  * is not loaded (an empty string as "filename" in the fsg_config
83  * structure causes error).  The CD-ROM emulation includes a single
84  * data track and no audio tracks; hence there need be only one
85  * backing file per LUN.  Note also that the CD-ROM block length is
86  * set to 512 rather than the more common value 2048.
87  *
88  *
89  * MSF includes support for module parameters.  If gadget using it
90  * decides to use it, the following module parameters will be
91  * available:
92  *
93  *      file=filename[,filename...]
94  *                      Names of the files or block devices used for
95  *                              backing storage.
96  *      ro=b[,b...]     Default false, boolean for read-only access.
97  *      removable=b[,b...]
98  *                      Default true, boolean for removable media.
99  *      cdrom=b[,b...]  Default false, boolean for whether to emulate
100  *                              a CD-ROM drive.
101  *      luns=N          Default N = number of filenames, number of
102  *                              LUNs to support.
103  *      stall           Default determined according to the type of
104  *                              USB device controller (usually true),
105  *                              boolean to permit the driver to halt
106  *                              bulk endpoints.
107  *
108  * The module parameters may be prefixed with some string.  You need
109  * to consult gadget's documentation or source to verify whether it is
110  * using those module parameters and if it does what are the prefixes
111  * (look for FSG_MODULE_PARAMETERS() macro usage, what's inside it is
112  * the prefix).
113  *
114  *
115  * Requirements are modest; only a bulk-in and a bulk-out endpoint are
116  * needed.  The memory requirement amounts to two 16K buffers, size
117  * configurable by a parameter.  Support is included for both
118  * full-speed and high-speed operation.
119  *
120  * Note that the driver is slightly non-portable in that it assumes a
121  * single memory/DMA buffer will be useable for bulk-in, bulk-out, and
122  * interrupt-in endpoints.  With most device controllers this isn't an
123  * issue, but there may be some with hardware restrictions that prevent
124  * a buffer from being used by more than one endpoint.
125  *
126  *
127  * The pathnames of the backing files and the ro settings are
128  * available in the attribute files "file" and "ro" in the lun<n> (or
129  * to be more precise in a directory which name comes from
130  * "lun_name_format" option!) subdirectory of the gadget's sysfs
131  * directory.  If the "removable" option is set, writing to these
132  * files will simulate ejecting/loading the medium (writing an empty
133  * line means eject) and adjusting a write-enable tab.  Changes to the
134  * ro setting are not allowed when the medium is loaded or if CD-ROM
135  * emulation is being used.
136  *
137  * When a LUN receive an "eject" SCSI request (Start/Stop Unit),
138  * if the LUN is removable, the backing file is released to simulate
139  * ejection.
140  *
141  *
142  * This function is heavily based on "File-backed Storage Gadget" by
143  * Alan Stern which in turn is heavily based on "Gadget Zero" by David
144  * Brownell.  The driver's SCSI command interface was based on the
145  * "Information technology - Small Computer System Interface - 2"
146  * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
147  * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
148  * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
149  * was based on the "Universal Serial Bus Mass Storage Class UFI
150  * Command Specification" document, Revision 1.0, December 14, 1998,
151  * available at
152  * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
153  */
154
155 /*
156  *                              Driver Design
157  *
158  * The MSF is fairly straightforward.  There is a main kernel
159  * thread that handles most of the work.  Interrupt routines field
160  * callbacks from the controller driver: bulk- and interrupt-request
161  * completion notifications, endpoint-0 events, and disconnect events.
162  * Completion events are passed to the main thread by wakeup calls.  Many
163  * ep0 requests are handled at interrupt time, but SetInterface,
164  * SetConfiguration, and device reset requests are forwarded to the
165  * thread in the form of "exceptions" using SIGUSR1 signals (since they
166  * should interrupt any ongoing file I/O operations).
167  *
168  * The thread's main routine implements the standard command/data/status
169  * parts of a SCSI interaction.  It and its subroutines are full of tests
170  * for pending signals/exceptions -- all this polling is necessary since
171  * the kernel has no setjmp/longjmp equivalents.  (Maybe this is an
172  * indication that the driver really wants to be running in userspace.)
173  * An important point is that so long as the thread is alive it keeps an
174  * open reference to the backing file.  This will prevent unmounting
175  * the backing file's underlying filesystem and could cause problems
176  * during system shutdown, for example.  To prevent such problems, the
177  * thread catches INT, TERM, and KILL signals and converts them into
178  * an EXIT exception.
179  *
180  * In normal operation the main thread is started during the gadget's
181  * fsg_bind() callback and stopped during fsg_unbind().  But it can
182  * also exit when it receives a signal, and there's no point leaving
183  * the gadget running when the thread is dead.  At of this moment, MSF
184  * provides no way to deregister the gadget when thread dies -- maybe
185  * a callback functions is needed.
186  *
187  * To provide maximum throughput, the driver uses a circular pipeline of
188  * buffer heads (struct fsg_buffhd).  In principle the pipeline can be
189  * arbitrarily long; in practice the benefits don't justify having more
190  * than 2 stages (i.e., double buffering).  But it helps to think of the
191  * pipeline as being a long one.  Each buffer head contains a bulk-in and
192  * a bulk-out request pointer (since the buffer can be used for both
193  * output and input -- directions always are given from the host's
194  * point of view) as well as a pointer to the buffer and various state
195  * variables.
196  *
197  * Use of the pipeline follows a simple protocol.  There is a variable
198  * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
199  * At any time that buffer head may still be in use from an earlier
200  * request, so each buffer head has a state variable indicating whether
201  * it is EMPTY, FULL, or BUSY.  Typical use involves waiting for the
202  * buffer head to be EMPTY, filling the buffer either by file I/O or by
203  * USB I/O (during which the buffer head is BUSY), and marking the buffer
204  * head FULL when the I/O is complete.  Then the buffer will be emptied
205  * (again possibly by USB I/O, during which it is marked BUSY) and
206  * finally marked EMPTY again (possibly by a completion routine).
207  *
208  * A module parameter tells the driver to avoid stalling the bulk
209  * endpoints wherever the transport specification allows.  This is
210  * necessary for some UDCs like the SuperH, which cannot reliably clear a
211  * halt on a bulk endpoint.  However, under certain circumstances the
212  * Bulk-only specification requires a stall.  In such cases the driver
213  * will halt the endpoint and set a flag indicating that it should clear
214  * the halt in software during the next device reset.  Hopefully this
215  * will permit everything to work correctly.  Furthermore, although the
216  * specification allows the bulk-out endpoint to halt when the host sends
217  * too much data, implementing this would cause an unavoidable race.
218  * The driver will always use the "no-stall" approach for OUT transfers.
219  *
220  * One subtle point concerns sending status-stage responses for ep0
221  * requests.  Some of these requests, such as device reset, can involve
222  * interrupting an ongoing file I/O operation, which might take an
223  * arbitrarily long time.  During that delay the host might give up on
224  * the original ep0 request and issue a new one.  When that happens the
225  * driver should not notify the host about completion of the original
226  * request, as the host will no longer be waiting for it.  So the driver
227  * assigns to each ep0 request a unique tag, and it keeps track of the
228  * tag value of the request associated with a long-running exception
229  * (device-reset, interface-change, or configuration-change).  When the
230  * exception handler is finished, the status-stage response is submitted
231  * only if the current ep0 request tag is equal to the exception request
232  * tag.  Thus only the most recently received ep0 request will get a
233  * status-stage response.
234  *
235  * Warning: This driver source file is too long.  It ought to be split up
236  * into a header file plus about 3 separate .c files, to handle the details
237  * of the Gadget, USB Mass Storage, and SCSI protocols.
238  */
239
240 /* #define VERBOSE_DEBUG */
241 /* #define DUMP_MSGS */
242
243 #include <config.h>
244 #include <malloc.h>
245 #include <common.h>
246 #include <g_dnl.h>
247 #include <watchdog.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/usb/gadget.h>
256 #include <linux/usb/gadget.h>
257 #include <linux/usb/composite.h>
258 #include <usb/lin_gadget_compat.h>
259 #include <g_dnl.h>
260
261 /*------------------------------------------------------------------------*/
262
263 #define FSG_DRIVER_DESC "Mass Storage Function"
264 #define FSG_DRIVER_VERSION      "2012/06/5"
265
266 static const char fsg_string_interface[] = "Mass Storage";
267
268 #define FSG_NO_INTR_EP 1
269 #define FSG_NO_DEVICE_STRINGS    1
270 #define FSG_NO_OTG               1
271 #define FSG_NO_INTR_EP           1
272
273 #include "storage_common.c"
274
275 /*-------------------------------------------------------------------------*/
276
277 #define GFP_ATOMIC ((gfp_t) 0)
278 #define PAGE_CACHE_SHIFT        12
279 #define PAGE_CACHE_SIZE         (1 << PAGE_CACHE_SHIFT)
280 #define kthread_create(...)     __builtin_return_address(0)
281 #define wait_for_completion(...) do {} while (0)
282
283 struct kref {int x; };
284 struct completion {int x; };
285
286 inline void set_bit(int nr, volatile void *addr)
287 {
288         int     mask;
289         unsigned int *a = (unsigned int *) addr;
290
291         a += nr >> 5;
292         mask = 1 << (nr & 0x1f);
293         *a |= mask;
294 }
295
296 inline void clear_bit(int nr, volatile void *addr)
297 {
298         int     mask;
299         unsigned int *a = (unsigned int *) addr;
300
301         a += nr >> 5;
302         mask = 1 << (nr & 0x1f);
303         *a &= ~mask;
304 }
305
306 struct fsg_dev;
307 struct fsg_common;
308
309 /* Data shared by all the FSG instances. */
310 struct fsg_common {
311         struct usb_gadget       *gadget;
312         struct fsg_dev          *fsg, *new_fsg;
313
314         struct usb_ep           *ep0;           /* Copy of gadget->ep0 */
315         struct usb_request      *ep0req;        /* Copy of cdev->req */
316         unsigned int            ep0_req_tag;
317
318         struct fsg_buffhd       *next_buffhd_to_fill;
319         struct fsg_buffhd       *next_buffhd_to_drain;
320         struct fsg_buffhd       buffhds[FSG_NUM_BUFFERS];
321
322         int                     cmnd_size;
323         u8                      cmnd[MAX_COMMAND_SIZE];
324
325         unsigned int            nluns;
326         unsigned int            lun;
327         struct fsg_lun          luns[FSG_MAX_LUNS];
328
329         unsigned int            bulk_out_maxpacket;
330         enum fsg_state          state;          /* For exception handling */
331         unsigned int            exception_req_tag;
332
333         enum data_direction     data_dir;
334         u32                     data_size;
335         u32                     data_size_from_cmnd;
336         u32                     tag;
337         u32                     residue;
338         u32                     usb_amount_left;
339
340         unsigned int            can_stall:1;
341         unsigned int            free_storage_on_release:1;
342         unsigned int            phase_error:1;
343         unsigned int            short_packet_received:1;
344         unsigned int            bad_lun_okay:1;
345         unsigned int            running:1;
346
347         int                     thread_wakeup_needed;
348         struct completion       thread_notifier;
349         struct task_struct      *thread_task;
350
351         /* Callback functions. */
352         const struct fsg_operations     *ops;
353         /* Gadget's private data. */
354         void                    *private_data;
355
356         const char *vendor_name;                /*  8 characters or less */
357         const char *product_name;               /* 16 characters or less */
358         u16 release;
359
360         /* Vendor (8 chars), product (16 chars), release (4
361          * hexadecimal digits) and NUL byte */
362         char inquiry_string[8 + 16 + 4 + 1];
363
364         struct kref             ref;
365 };
366
367 struct fsg_config {
368         unsigned nluns;
369         struct fsg_lun_config {
370                 const char *filename;
371                 char ro;
372                 char removable;
373                 char cdrom;
374                 char nofua;
375         } luns[FSG_MAX_LUNS];
376
377         /* Callback functions. */
378         const struct fsg_operations     *ops;
379         /* Gadget's private data. */
380         void                    *private_data;
381
382         const char *vendor_name;                /*  8 characters or less */
383         const char *product_name;               /* 16 characters or less */
384
385         char                    can_stall;
386 };
387
388 struct fsg_dev {
389         struct usb_function     function;
390         struct usb_gadget       *gadget;        /* Copy of cdev->gadget */
391         struct fsg_common       *common;
392
393         u16                     interface_number;
394
395         unsigned int            bulk_in_enabled:1;
396         unsigned int            bulk_out_enabled:1;
397
398         unsigned long           atomic_bitflags;
399 #define IGNORE_BULK_OUT         0
400
401         struct usb_ep           *bulk_in;
402         struct usb_ep           *bulk_out;
403 };
404
405
406 static inline int __fsg_is_set(struct fsg_common *common,
407                                const char *func, unsigned line)
408 {
409         if (common->fsg)
410                 return 1;
411         ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
412         WARN_ON(1);
413         return 0;
414 }
415
416 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
417
418
419 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
420 {
421         return container_of(f, struct fsg_dev, function);
422 }
423
424
425 typedef void (*fsg_routine_t)(struct fsg_dev *);
426
427 static int exception_in_progress(struct fsg_common *common)
428 {
429         return common->state > FSG_STATE_IDLE;
430 }
431
432 /* Make bulk-out requests be divisible by the maxpacket size */
433 static void set_bulk_out_req_length(struct fsg_common *common,
434                 struct fsg_buffhd *bh, unsigned int length)
435 {
436         unsigned int    rem;
437
438         bh->bulk_out_intended_length = length;
439         rem = length % common->bulk_out_maxpacket;
440         if (rem > 0)
441                 length += common->bulk_out_maxpacket - rem;
442         bh->outreq->length = length;
443 }
444
445 /*-------------------------------------------------------------------------*/
446
447 struct ums *ums;
448 struct fsg_common *the_fsg_common;
449
450 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
451 {
452         const char      *name;
453
454         if (ep == fsg->bulk_in)
455                 name = "bulk-in";
456         else if (ep == fsg->bulk_out)
457                 name = "bulk-out";
458         else
459                 name = ep->name;
460         DBG(fsg, "%s set halt\n", name);
461         return usb_ep_set_halt(ep);
462 }
463
464 /*-------------------------------------------------------------------------*/
465
466 /* These routines may be called in process context or in_irq */
467
468 /* Caller must hold fsg->lock */
469 static void wakeup_thread(struct fsg_common *common)
470 {
471         common->thread_wakeup_needed = 1;
472 }
473
474 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
475 {
476         /* Do nothing if a higher-priority exception is already in progress.
477          * If a lower-or-equal priority exception is in progress, preempt it
478          * and notify the main thread by sending it a signal. */
479         if (common->state <= new_state) {
480                 common->exception_req_tag = common->ep0_req_tag;
481                 common->state = new_state;
482                 common->thread_wakeup_needed = 1;
483         }
484 }
485
486 /*-------------------------------------------------------------------------*/
487
488 static int ep0_queue(struct fsg_common *common)
489 {
490         int     rc;
491
492         rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
493         common->ep0->driver_data = common;
494         if (rc != 0 && rc != -ESHUTDOWN) {
495                 /* We can't do much more than wait for a reset */
496                 WARNING(common, "error in submission: %s --> %d\n",
497                         common->ep0->name, rc);
498         }
499         return rc;
500 }
501
502 /*-------------------------------------------------------------------------*/
503
504 /* Bulk and interrupt endpoint completion handlers.
505  * These always run in_irq. */
506
507 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
508 {
509         struct fsg_common       *common = ep->driver_data;
510         struct fsg_buffhd       *bh = req->context;
511
512         if (req->status || req->actual != req->length)
513                 DBG(common, "%s --> %d, %u/%u\n", __func__,
514                                 req->status, req->actual, req->length);
515         if (req->status == -ECONNRESET)         /* Request was cancelled */
516                 usb_ep_fifo_flush(ep);
517
518         /* Hold the lock while we update the request and buffer states */
519         bh->inreq_busy = 0;
520         bh->state = BUF_STATE_EMPTY;
521         wakeup_thread(common);
522 }
523
524 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
525 {
526         struct fsg_common       *common = ep->driver_data;
527         struct fsg_buffhd       *bh = req->context;
528
529         dump_msg(common, "bulk-out", req->buf, req->actual);
530         if (req->status || req->actual != bh->bulk_out_intended_length)
531                 DBG(common, "%s --> %d, %u/%u\n", __func__,
532                                 req->status, req->actual,
533                                 bh->bulk_out_intended_length);
534         if (req->status == -ECONNRESET)         /* Request was cancelled */
535                 usb_ep_fifo_flush(ep);
536
537         /* Hold the lock while we update the request and buffer states */
538         bh->outreq_busy = 0;
539         bh->state = BUF_STATE_FULL;
540         wakeup_thread(common);
541 }
542
543 /*-------------------------------------------------------------------------*/
544
545 /* Ep0 class-specific handlers.  These always run in_irq. */
546
547 static int fsg_setup(struct usb_function *f,
548                 const struct usb_ctrlrequest *ctrl)
549 {
550         struct fsg_dev          *fsg = fsg_from_func(f);
551         struct usb_request      *req = fsg->common->ep0req;
552         u16                     w_index = get_unaligned_le16(&ctrl->wIndex);
553         u16                     w_value = get_unaligned_le16(&ctrl->wValue);
554         u16                     w_length = get_unaligned_le16(&ctrl->wLength);
555
556         if (!fsg_is_set(fsg->common))
557                 return -EOPNOTSUPP;
558
559         switch (ctrl->bRequest) {
560
561         case USB_BULK_RESET_REQUEST:
562                 if (ctrl->bRequestType !=
563                     (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
564                         break;
565                 if (w_index != fsg->interface_number || w_value != 0)
566                         return -EDOM;
567
568                 /* Raise an exception to stop the current operation
569                  * and reinitialize our state. */
570                 DBG(fsg, "bulk reset request\n");
571                 raise_exception(fsg->common, FSG_STATE_RESET);
572                 return DELAYED_STATUS;
573
574         case USB_BULK_GET_MAX_LUN_REQUEST:
575                 if (ctrl->bRequestType !=
576                     (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
577                         break;
578                 if (w_index != fsg->interface_number || w_value != 0)
579                         return -EDOM;
580                 VDBG(fsg, "get max LUN\n");
581                 *(u8 *) req->buf = fsg->common->nluns - 1;
582
583                 /* Respond with data/status */
584                 req->length = min((u16)1, w_length);
585                 return ep0_queue(fsg->common);
586         }
587
588         VDBG(fsg,
589              "unknown class-specific control req "
590              "%02x.%02x v%04x i%04x l%u\n",
591              ctrl->bRequestType, ctrl->bRequest,
592              get_unaligned_le16(&ctrl->wValue), w_index, w_length);
593         return -EOPNOTSUPP;
594 }
595
596 /*-------------------------------------------------------------------------*/
597
598 /* All the following routines run in process context */
599
600 /* Use this for bulk or interrupt transfers, not ep0 */
601 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
602                 struct usb_request *req, int *pbusy,
603                 enum fsg_buffer_state *state)
604 {
605         int     rc;
606
607         if (ep == fsg->bulk_in)
608                 dump_msg(fsg, "bulk-in", req->buf, req->length);
609
610         *pbusy = 1;
611         *state = BUF_STATE_BUSY;
612         rc = usb_ep_queue(ep, req, GFP_KERNEL);
613         if (rc != 0) {
614                 *pbusy = 0;
615                 *state = BUF_STATE_EMPTY;
616
617                 /* We can't do much more than wait for a reset */
618
619                 /* Note: currently the net2280 driver fails zero-length
620                  * submissions if DMA is enabled. */
621                 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
622                                                 req->length == 0))
623                         WARNING(fsg, "error in submission: %s --> %d\n",
624                                         ep->name, rc);
625         }
626 }
627
628 #define START_TRANSFER_OR(common, ep_name, req, pbusy, state)           \
629         if (fsg_is_set(common))                                         \
630                 start_transfer((common)->fsg, (common)->fsg->ep_name,   \
631                                req, pbusy, state);                      \
632         else
633
634 #define START_TRANSFER(common, ep_name, req, pbusy, state)              \
635         START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
636
637 static void busy_indicator(void)
638 {
639         static int state;
640
641         switch (state) {
642         case 0:
643                 puts("\r|"); break;
644         case 1:
645                 puts("\r/"); break;
646         case 2:
647                 puts("\r-"); break;
648         case 3:
649                 puts("\r\\"); break;
650         case 4:
651                 puts("\r|"); break;
652         case 5:
653                 puts("\r/"); break;
654         case 6:
655                 puts("\r-"); break;
656         case 7:
657                 puts("\r\\"); break;
658         default:
659                 state = 0;
660         }
661         if (state++ == 8)
662                 state = 0;
663 }
664
665 static int sleep_thread(struct fsg_common *common)
666 {
667         int     rc = 0;
668         int i = 0, k = 0;
669
670         /* Wait until a signal arrives or we are woken up */
671         for (;;) {
672                 if (common->thread_wakeup_needed)
673                         break;
674
675                 if (++i == 20000) {
676                         busy_indicator();
677                         i = 0;
678                         k++;
679                 }
680
681                 if (k == 10) {
682                         /* Handle CTRL+C */
683                         if (ctrlc())
684                                 return -EPIPE;
685
686                         WATCHDOG_RESET();
687
688                         /* Check cable connection */
689                         if (!g_dnl_board_usb_cable_connected())
690                                 return -EIO;
691
692                         k = 0;
693                 }
694
695                 usb_gadget_handle_interrupts(0);
696         }
697         common->thread_wakeup_needed = 0;
698         return rc;
699 }
700
701 /*-------------------------------------------------------------------------*/
702
703 static int do_read(struct fsg_common *common)
704 {
705         struct fsg_lun          *curlun = &common->luns[common->lun];
706         u32                     lba;
707         struct fsg_buffhd       *bh;
708         int                     rc;
709         u32                     amount_left;
710         loff_t                  file_offset;
711         unsigned int            amount;
712         unsigned int            partial_page;
713         ssize_t                 nread;
714
715         /* Get the starting Logical Block Address and check that it's
716          * not too big */
717         if (common->cmnd[0] == SC_READ_6)
718                 lba = get_unaligned_be24(&common->cmnd[1]);
719         else {
720                 lba = get_unaligned_be32(&common->cmnd[2]);
721
722                 /* We allow DPO (Disable Page Out = don't save data in the
723                  * cache) and FUA (Force Unit Access = don't read from the
724                  * cache), but we don't implement them. */
725                 if ((common->cmnd[1] & ~0x18) != 0) {
726                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
727                         return -EINVAL;
728                 }
729         }
730         if (lba >= curlun->num_sectors) {
731                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
732                 return -EINVAL;
733         }
734         file_offset = ((loff_t) lba) << 9;
735
736         /* Carry out the file reads */
737         amount_left = common->data_size_from_cmnd;
738         if (unlikely(amount_left == 0))
739                 return -EIO;            /* No default reply */
740
741         for (;;) {
742
743                 /* Figure out how much we need to read:
744                  * Try to read the remaining amount.
745                  * But don't read more than the buffer size.
746                  * And don't try to read past the end of the file.
747                  * Finally, if we're not at a page boundary, don't read past
748                  *      the next page.
749                  * If this means reading 0 then we were asked to read past
750                  *      the end of file. */
751                 amount = min(amount_left, FSG_BUFLEN);
752                 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
753                 if (partial_page > 0)
754                         amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
755                                         partial_page);
756
757                 /* Wait for the next buffer to become available */
758                 bh = common->next_buffhd_to_fill;
759                 while (bh->state != BUF_STATE_EMPTY) {
760                         rc = sleep_thread(common);
761                         if (rc)
762                                 return rc;
763                 }
764
765                 /* If we were asked to read past the end of file,
766                  * end with an empty buffer. */
767                 if (amount == 0) {
768                         curlun->sense_data =
769                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
770                         curlun->info_valid = 1;
771                         bh->inreq->length = 0;
772                         bh->state = BUF_STATE_FULL;
773                         break;
774                 }
775
776                 /* Perform the read */
777                 rc = ums->read_sector(ums,
778                                       file_offset / SECTOR_SIZE,
779                                       amount / SECTOR_SIZE,
780                                       (char __user *)bh->buf);
781                 if (!rc)
782                         return -EIO;
783
784                 nread = rc * SECTOR_SIZE;
785
786                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
787                                 (unsigned long long) file_offset,
788                                 (int) nread);
789
790                 if (nread < 0) {
791                         LDBG(curlun, "error in file read: %d\n",
792                                         (int) nread);
793                         nread = 0;
794                 } else if (nread < amount) {
795                         LDBG(curlun, "partial file read: %d/%u\n",
796                                         (int) nread, amount);
797                         nread -= (nread & 511); /* Round down to a block */
798                 }
799                 file_offset  += nread;
800                 amount_left  -= nread;
801                 common->residue -= nread;
802                 bh->inreq->length = nread;
803                 bh->state = BUF_STATE_FULL;
804
805                 /* If an error occurred, report it and its position */
806                 if (nread < amount) {
807                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
808                         curlun->info_valid = 1;
809                         break;
810                 }
811
812                 if (amount_left == 0)
813                         break;          /* No more left to read */
814
815                 /* Send this buffer and go read some more */
816                 bh->inreq->zero = 0;
817                 START_TRANSFER_OR(common, bulk_in, bh->inreq,
818                                &bh->inreq_busy, &bh->state)
819                         /* Don't know what to do if
820                          * common->fsg is NULL */
821                         return -EIO;
822                 common->next_buffhd_to_fill = bh->next;
823         }
824
825         return -EIO;            /* No default reply */
826 }
827
828 /*-------------------------------------------------------------------------*/
829
830 static int do_write(struct fsg_common *common)
831 {
832         struct fsg_lun          *curlun = &common->luns[common->lun];
833         u32                     lba;
834         struct fsg_buffhd       *bh;
835         int                     get_some_more;
836         u32                     amount_left_to_req, amount_left_to_write;
837         loff_t                  usb_offset, file_offset;
838         unsigned int            amount;
839         unsigned int            partial_page;
840         ssize_t                 nwritten;
841         int                     rc;
842
843         if (curlun->ro) {
844                 curlun->sense_data = SS_WRITE_PROTECTED;
845                 return -EINVAL;
846         }
847
848         /* Get the starting Logical Block Address and check that it's
849          * not too big */
850         if (common->cmnd[0] == SC_WRITE_6)
851                 lba = get_unaligned_be24(&common->cmnd[1]);
852         else {
853                 lba = get_unaligned_be32(&common->cmnd[2]);
854
855                 /* We allow DPO (Disable Page Out = don't save data in the
856                  * cache) and FUA (Force Unit Access = write directly to the
857                  * medium).  We don't implement DPO; we implement FUA by
858                  * performing synchronous output. */
859                 if (common->cmnd[1] & ~0x18) {
860                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
861                         return -EINVAL;
862                 }
863         }
864         if (lba >= curlun->num_sectors) {
865                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
866                 return -EINVAL;
867         }
868
869         /* Carry out the file writes */
870         get_some_more = 1;
871         file_offset = usb_offset = ((loff_t) lba) << 9;
872         amount_left_to_req = common->data_size_from_cmnd;
873         amount_left_to_write = common->data_size_from_cmnd;
874
875         while (amount_left_to_write > 0) {
876
877                 /* Queue a request for more data from the host */
878                 bh = common->next_buffhd_to_fill;
879                 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
880
881                         /* Figure out how much we want to get:
882                          * Try to get the remaining amount.
883                          * But don't get more than the buffer size.
884                          * And don't try to go past the end of the file.
885                          * If we're not at a page boundary,
886                          *      don't go past the next page.
887                          * If this means getting 0, then we were asked
888                          *      to write past the end of file.
889                          * Finally, round down to a block boundary. */
890                         amount = min(amount_left_to_req, FSG_BUFLEN);
891                         partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
892                         if (partial_page > 0)
893                                 amount = min(amount,
894         (unsigned int) PAGE_CACHE_SIZE - partial_page);
895
896                         if (amount == 0) {
897                                 get_some_more = 0;
898                                 curlun->sense_data =
899                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
900                                 curlun->info_valid = 1;
901                                 continue;
902                         }
903                         amount -= (amount & 511);
904                         if (amount == 0) {
905
906                                 /* Why were we were asked to transfer a
907                                  * partial block? */
908                                 get_some_more = 0;
909                                 continue;
910                         }
911
912                         /* Get the next buffer */
913                         usb_offset += amount;
914                         common->usb_amount_left -= amount;
915                         amount_left_to_req -= amount;
916                         if (amount_left_to_req == 0)
917                                 get_some_more = 0;
918
919                         /* amount is always divisible by 512, hence by
920                          * the bulk-out maxpacket size */
921                         bh->outreq->length = amount;
922                         bh->bulk_out_intended_length = amount;
923                         bh->outreq->short_not_ok = 1;
924                         START_TRANSFER_OR(common, bulk_out, bh->outreq,
925                                           &bh->outreq_busy, &bh->state)
926                                 /* Don't know what to do if
927                                  * common->fsg is NULL */
928                                 return -EIO;
929                         common->next_buffhd_to_fill = bh->next;
930                         continue;
931                 }
932
933                 /* Write the received data to the backing file */
934                 bh = common->next_buffhd_to_drain;
935                 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
936                         break;                  /* We stopped early */
937                 if (bh->state == BUF_STATE_FULL) {
938                         common->next_buffhd_to_drain = bh->next;
939                         bh->state = BUF_STATE_EMPTY;
940
941                         /* Did something go wrong with the transfer? */
942                         if (bh->outreq->status != 0) {
943                                 curlun->sense_data = SS_COMMUNICATION_FAILURE;
944                                 curlun->info_valid = 1;
945                                 break;
946                         }
947
948                         amount = bh->outreq->actual;
949
950                         /* Perform the write */
951                         rc = ums->write_sector(ums,
952                                                file_offset / SECTOR_SIZE,
953                                                amount / SECTOR_SIZE,
954                                                (char __user *)bh->buf);
955                         if (!rc)
956                                 return -EIO;
957                         nwritten = rc * SECTOR_SIZE;
958
959                         VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
960                                         (unsigned long long) file_offset,
961                                         (int) nwritten);
962
963                         if (nwritten < 0) {
964                                 LDBG(curlun, "error in file write: %d\n",
965                                                 (int) nwritten);
966                                 nwritten = 0;
967                         } else if (nwritten < amount) {
968                                 LDBG(curlun, "partial file write: %d/%u\n",
969                                                 (int) nwritten, amount);
970                                 nwritten -= (nwritten & 511);
971                                 /* Round down to a block */
972                         }
973                         file_offset += nwritten;
974                         amount_left_to_write -= nwritten;
975                         common->residue -= nwritten;
976
977                         /* If an error occurred, report it and its position */
978                         if (nwritten < amount) {
979                                 printf("nwritten:%zd amount:%u\n", nwritten,
980                                        amount);
981                                 curlun->sense_data = SS_WRITE_ERROR;
982                                 curlun->info_valid = 1;
983                                 break;
984                         }
985
986                         /* Did the host decide to stop early? */
987                         if (bh->outreq->actual != bh->outreq->length) {
988                                 common->short_packet_received = 1;
989                                 break;
990                         }
991                         continue;
992                 }
993
994                 /* Wait for something to happen */
995                 rc = sleep_thread(common);
996                 if (rc)
997                         return rc;
998         }
999
1000         return -EIO;            /* No default reply */
1001 }
1002
1003 /*-------------------------------------------------------------------------*/
1004
1005 static int do_synchronize_cache(struct fsg_common *common)
1006 {
1007         return 0;
1008 }
1009
1010 /*-------------------------------------------------------------------------*/
1011
1012 static int do_verify(struct fsg_common *common)
1013 {
1014         struct fsg_lun          *curlun = &common->luns[common->lun];
1015         u32                     lba;
1016         u32                     verification_length;
1017         struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
1018         loff_t                  file_offset;
1019         u32                     amount_left;
1020         unsigned int            amount;
1021         ssize_t                 nread;
1022         int                     rc;
1023
1024         /* Get the starting Logical Block Address and check that it's
1025          * not too big */
1026         lba = get_unaligned_be32(&common->cmnd[2]);
1027         if (lba >= curlun->num_sectors) {
1028                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1029                 return -EINVAL;
1030         }
1031
1032         /* We allow DPO (Disable Page Out = don't save data in the
1033          * cache) but we don't implement it. */
1034         if (common->cmnd[1] & ~0x10) {
1035                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1036                 return -EINVAL;
1037         }
1038
1039         verification_length = get_unaligned_be16(&common->cmnd[7]);
1040         if (unlikely(verification_length == 0))
1041                 return -EIO;            /* No default reply */
1042
1043         /* Prepare to carry out the file verify */
1044         amount_left = verification_length << 9;
1045         file_offset = ((loff_t) lba) << 9;
1046
1047         /* Write out all the dirty buffers before invalidating them */
1048
1049         /* Just try to read the requested blocks */
1050         while (amount_left > 0) {
1051
1052                 /* Figure out how much we need to read:
1053                  * Try to read the remaining amount, but not more than
1054                  * the buffer size.
1055                  * And don't try to read past the end of the file.
1056                  * If this means reading 0 then we were asked to read
1057                  * past the end of file. */
1058                 amount = min(amount_left, FSG_BUFLEN);
1059                 if (amount == 0) {
1060                         curlun->sense_data =
1061                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1062                         curlun->info_valid = 1;
1063                         break;
1064                 }
1065
1066                 /* Perform the read */
1067                 rc = ums->read_sector(ums,
1068                                       file_offset / SECTOR_SIZE,
1069                                       amount / SECTOR_SIZE,
1070                                       (char __user *)bh->buf);
1071                 if (!rc)
1072                         return -EIO;
1073                 nread = rc * SECTOR_SIZE;
1074
1075                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1076                                 (unsigned long long) file_offset,
1077                                 (int) nread);
1078                 if (nread < 0) {
1079                         LDBG(curlun, "error in file verify: %d\n",
1080                                         (int) nread);
1081                         nread = 0;
1082                 } else if (nread < amount) {
1083                         LDBG(curlun, "partial file verify: %d/%u\n",
1084                                         (int) nread, amount);
1085                         nread -= (nread & 511); /* Round down to a sector */
1086                 }
1087                 if (nread == 0) {
1088                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1089                         curlun->info_valid = 1;
1090                         break;
1091                 }
1092                 file_offset += nread;
1093                 amount_left -= nread;
1094         }
1095         return 0;
1096 }
1097
1098 /*-------------------------------------------------------------------------*/
1099
1100 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1101 {
1102         struct fsg_lun *curlun = &common->luns[common->lun];
1103         static const char vendor_id[] = "Linux   ";
1104         u8      *buf = (u8 *) bh->buf;
1105
1106         if (!curlun) {          /* Unsupported LUNs are okay */
1107                 common->bad_lun_okay = 1;
1108                 memset(buf, 0, 36);
1109                 buf[0] = 0x7f;          /* Unsupported, no device-type */
1110                 buf[4] = 31;            /* Additional length */
1111                 return 36;
1112         }
1113
1114         memset(buf, 0, 8);
1115         buf[0] = TYPE_DISK;
1116         buf[1] = curlun->removable ? 0x80 : 0;
1117         buf[2] = 2;             /* ANSI SCSI level 2 */
1118         buf[3] = 2;             /* SCSI-2 INQUIRY data format */
1119         buf[4] = 31;            /* Additional length */
1120                                 /* No special options */
1121         sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
1122                         ums->name, (u16) 0xffff);
1123
1124         return 36;
1125 }
1126
1127
1128 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1129 {
1130         struct fsg_lun  *curlun = &common->luns[common->lun];
1131         u8              *buf = (u8 *) bh->buf;
1132         u32             sd, sdinfo;
1133         int             valid;
1134
1135         /*
1136          * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1137          *
1138          * If a REQUEST SENSE command is received from an initiator
1139          * with a pending unit attention condition (before the target
1140          * generates the contingent allegiance condition), then the
1141          * target shall either:
1142          *   a) report any pending sense data and preserve the unit
1143          *      attention condition on the logical unit, or,
1144          *   b) report the unit attention condition, may discard any
1145          *      pending sense data, and clear the unit attention
1146          *      condition on the logical unit for that initiator.
1147          *
1148          * FSG normally uses option a); enable this code to use option b).
1149          */
1150 #if 0
1151         if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1152                 curlun->sense_data = curlun->unit_attention_data;
1153                 curlun->unit_attention_data = SS_NO_SENSE;
1154         }
1155 #endif
1156
1157         if (!curlun) {          /* Unsupported LUNs are okay */
1158                 common->bad_lun_okay = 1;
1159                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1160                 sdinfo = 0;
1161                 valid = 0;
1162         } else {
1163                 sd = curlun->sense_data;
1164                 valid = curlun->info_valid << 7;
1165                 curlun->sense_data = SS_NO_SENSE;
1166                 curlun->info_valid = 0;
1167         }
1168
1169         memset(buf, 0, 18);
1170         buf[0] = valid | 0x70;                  /* Valid, current error */
1171         buf[2] = SK(sd);
1172         put_unaligned_be32(sdinfo, &buf[3]);    /* Sense information */
1173         buf[7] = 18 - 8;                        /* Additional sense length */
1174         buf[12] = ASC(sd);
1175         buf[13] = ASCQ(sd);
1176         return 18;
1177 }
1178
1179 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1180 {
1181         struct fsg_lun  *curlun = &common->luns[common->lun];
1182         u32             lba = get_unaligned_be32(&common->cmnd[2]);
1183         int             pmi = common->cmnd[8];
1184         u8              *buf = (u8 *) bh->buf;
1185
1186         /* Check the PMI and LBA fields */
1187         if (pmi > 1 || (pmi == 0 && lba != 0)) {
1188                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1189                 return -EINVAL;
1190         }
1191
1192         put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1193                                                 /* Max logical block */
1194         put_unaligned_be32(512, &buf[4]);       /* Block length */
1195         return 8;
1196 }
1197
1198 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1199 {
1200         struct fsg_lun  *curlun = &common->luns[common->lun];
1201         int             msf = common->cmnd[1] & 0x02;
1202         u32             lba = get_unaligned_be32(&common->cmnd[2]);
1203         u8              *buf = (u8 *) bh->buf;
1204
1205         if (common->cmnd[1] & ~0x02) {          /* Mask away MSF */
1206                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1207                 return -EINVAL;
1208         }
1209         if (lba >= curlun->num_sectors) {
1210                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1211                 return -EINVAL;
1212         }
1213
1214         memset(buf, 0, 8);
1215         buf[0] = 0x01;          /* 2048 bytes of user data, rest is EC */
1216         store_cdrom_address(&buf[4], msf, lba);
1217         return 8;
1218 }
1219
1220
1221 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1222 {
1223         struct fsg_lun  *curlun = &common->luns[common->lun];
1224         int             msf = common->cmnd[1] & 0x02;
1225         int             start_track = common->cmnd[6];
1226         u8              *buf = (u8 *) bh->buf;
1227
1228         if ((common->cmnd[1] & ~0x02) != 0 ||   /* Mask away MSF */
1229                         start_track > 1) {
1230                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1231                 return -EINVAL;
1232         }
1233
1234         memset(buf, 0, 20);
1235         buf[1] = (20-2);                /* TOC data length */
1236         buf[2] = 1;                     /* First track number */
1237         buf[3] = 1;                     /* Last track number */
1238         buf[5] = 0x16;                  /* Data track, copying allowed */
1239         buf[6] = 0x01;                  /* Only track is number 1 */
1240         store_cdrom_address(&buf[8], msf, 0);
1241
1242         buf[13] = 0x16;                 /* Lead-out track is data */
1243         buf[14] = 0xAA;                 /* Lead-out track number */
1244         store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1245
1246         return 20;
1247 }
1248
1249 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1250 {
1251         struct fsg_lun  *curlun = &common->luns[common->lun];
1252         int             mscmnd = common->cmnd[0];
1253         u8              *buf = (u8 *) bh->buf;
1254         u8              *buf0 = buf;
1255         int             pc, page_code;
1256         int             changeable_values, all_pages;
1257         int             valid_page = 0;
1258         int             len, limit;
1259
1260         if ((common->cmnd[1] & ~0x08) != 0) {   /* Mask away DBD */
1261                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1262                 return -EINVAL;
1263         }
1264         pc = common->cmnd[2] >> 6;
1265         page_code = common->cmnd[2] & 0x3f;
1266         if (pc == 3) {
1267                 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1268                 return -EINVAL;
1269         }
1270         changeable_values = (pc == 1);
1271         all_pages = (page_code == 0x3f);
1272
1273         /* Write the mode parameter header.  Fixed values are: default
1274          * medium type, no cache control (DPOFUA), and no block descriptors.
1275          * The only variable value is the WriteProtect bit.  We will fill in
1276          * the mode data length later. */
1277         memset(buf, 0, 8);
1278         if (mscmnd == SC_MODE_SENSE_6) {
1279                 buf[2] = (curlun->ro ? 0x80 : 0x00);            /* WP, DPOFUA */
1280                 buf += 4;
1281                 limit = 255;
1282         } else {                        /* SC_MODE_SENSE_10 */
1283                 buf[3] = (curlun->ro ? 0x80 : 0x00);            /* WP, DPOFUA */
1284                 buf += 8;
1285                 limit = 65535;          /* Should really be FSG_BUFLEN */
1286         }
1287
1288         /* No block descriptors */
1289
1290         /* The mode pages, in numerical order.  The only page we support
1291          * is the Caching page. */
1292         if (page_code == 0x08 || all_pages) {
1293                 valid_page = 1;
1294                 buf[0] = 0x08;          /* Page code */
1295                 buf[1] = 10;            /* Page length */
1296                 memset(buf+2, 0, 10);   /* None of the fields are changeable */
1297
1298                 if (!changeable_values) {
1299                         buf[2] = 0x04;  /* Write cache enable, */
1300                                         /* Read cache not disabled */
1301                                         /* No cache retention priorities */
1302                         put_unaligned_be16(0xffff, &buf[4]);
1303                                         /* Don't disable prefetch */
1304                                         /* Minimum prefetch = 0 */
1305                         put_unaligned_be16(0xffff, &buf[8]);
1306                                         /* Maximum prefetch */
1307                         put_unaligned_be16(0xffff, &buf[10]);
1308                                         /* Maximum prefetch ceiling */
1309                 }
1310                 buf += 12;
1311         }
1312
1313         /* Check that a valid page was requested and the mode data length
1314          * isn't too long. */
1315         len = buf - buf0;
1316         if (!valid_page || len > limit) {
1317                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1318                 return -EINVAL;
1319         }
1320
1321         /*  Store the mode data length */
1322         if (mscmnd == SC_MODE_SENSE_6)
1323                 buf0[0] = len - 1;
1324         else
1325                 put_unaligned_be16(len - 2, buf0);
1326         return len;
1327 }
1328
1329
1330 static int do_start_stop(struct fsg_common *common)
1331 {
1332         struct fsg_lun  *curlun = &common->luns[common->lun];
1333
1334         if (!curlun) {
1335                 return -EINVAL;
1336         } else if (!curlun->removable) {
1337                 curlun->sense_data = SS_INVALID_COMMAND;
1338                 return -EINVAL;
1339         }
1340
1341         return 0;
1342 }
1343
1344 static int do_prevent_allow(struct fsg_common *common)
1345 {
1346         struct fsg_lun  *curlun = &common->luns[common->lun];
1347         int             prevent;
1348
1349         if (!curlun->removable) {
1350                 curlun->sense_data = SS_INVALID_COMMAND;
1351                 return -EINVAL;
1352         }
1353
1354         prevent = common->cmnd[4] & 0x01;
1355         if ((common->cmnd[4] & ~0x01) != 0) {   /* Mask away Prevent */
1356                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1357                 return -EINVAL;
1358         }
1359
1360         if (curlun->prevent_medium_removal && !prevent)
1361                 fsg_lun_fsync_sub(curlun);
1362         curlun->prevent_medium_removal = prevent;
1363         return 0;
1364 }
1365
1366
1367 static int do_read_format_capacities(struct fsg_common *common,
1368                         struct fsg_buffhd *bh)
1369 {
1370         struct fsg_lun  *curlun = &common->luns[common->lun];
1371         u8              *buf = (u8 *) bh->buf;
1372
1373         buf[0] = buf[1] = buf[2] = 0;
1374         buf[3] = 8;     /* Only the Current/Maximum Capacity Descriptor */
1375         buf += 4;
1376
1377         put_unaligned_be32(curlun->num_sectors, &buf[0]);
1378                                                 /* Number of blocks */
1379         put_unaligned_be32(512, &buf[4]);       /* Block length */
1380         buf[4] = 0x02;                          /* Current capacity */
1381         return 12;
1382 }
1383
1384
1385 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1386 {
1387         struct fsg_lun  *curlun = &common->luns[common->lun];
1388
1389         /* We don't support MODE SELECT */
1390         if (curlun)
1391                 curlun->sense_data = SS_INVALID_COMMAND;
1392         return -EINVAL;
1393 }
1394
1395
1396 /*-------------------------------------------------------------------------*/
1397
1398 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1399 {
1400         int     rc;
1401
1402         rc = fsg_set_halt(fsg, fsg->bulk_in);
1403         if (rc == -EAGAIN)
1404                 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1405         while (rc != 0) {
1406                 if (rc != -EAGAIN) {
1407                         WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1408                         rc = 0;
1409                         break;
1410                 }
1411
1412                 rc = usb_ep_set_halt(fsg->bulk_in);
1413         }
1414         return rc;
1415 }
1416
1417 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1418 {
1419         int     rc;
1420
1421         DBG(fsg, "bulk-in set wedge\n");
1422         rc = 0; /* usb_ep_set_wedge(fsg->bulk_in); */
1423         if (rc == -EAGAIN)
1424                 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1425         while (rc != 0) {
1426                 if (rc != -EAGAIN) {
1427                         WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1428                         rc = 0;
1429                         break;
1430                 }
1431         }
1432         return rc;
1433 }
1434
1435 static int pad_with_zeros(struct fsg_dev *fsg)
1436 {
1437         struct fsg_buffhd       *bh = fsg->common->next_buffhd_to_fill;
1438         u32                     nkeep = bh->inreq->length;
1439         u32                     nsend;
1440         int                     rc;
1441
1442         bh->state = BUF_STATE_EMPTY;            /* For the first iteration */
1443         fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1444         while (fsg->common->usb_amount_left > 0) {
1445
1446                 /* Wait for the next buffer to be free */
1447                 while (bh->state != BUF_STATE_EMPTY) {
1448                         rc = sleep_thread(fsg->common);
1449                         if (rc)
1450                                 return rc;
1451                 }
1452
1453                 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1454                 memset(bh->buf + nkeep, 0, nsend - nkeep);
1455                 bh->inreq->length = nsend;
1456                 bh->inreq->zero = 0;
1457                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1458                                 &bh->inreq_busy, &bh->state);
1459                 bh = fsg->common->next_buffhd_to_fill = bh->next;
1460                 fsg->common->usb_amount_left -= nsend;
1461                 nkeep = 0;
1462         }
1463         return 0;
1464 }
1465
1466 static int throw_away_data(struct fsg_common *common)
1467 {
1468         struct fsg_buffhd       *bh;
1469         u32                     amount;
1470         int                     rc;
1471
1472         for (bh = common->next_buffhd_to_drain;
1473              bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1474              bh = common->next_buffhd_to_drain) {
1475
1476                 /* Throw away the data in a filled buffer */
1477                 if (bh->state == BUF_STATE_FULL) {
1478                         bh->state = BUF_STATE_EMPTY;
1479                         common->next_buffhd_to_drain = bh->next;
1480
1481                         /* A short packet or an error ends everything */
1482                         if (bh->outreq->actual != bh->outreq->length ||
1483                                         bh->outreq->status != 0) {
1484                                 raise_exception(common,
1485                                                 FSG_STATE_ABORT_BULK_OUT);
1486                                 return -EINTR;
1487                         }
1488                         continue;
1489                 }
1490
1491                 /* Try to submit another request if we need one */
1492                 bh = common->next_buffhd_to_fill;
1493                 if (bh->state == BUF_STATE_EMPTY
1494                  && common->usb_amount_left > 0) {
1495                         amount = min(common->usb_amount_left, FSG_BUFLEN);
1496
1497                         /* amount is always divisible by 512, hence by
1498                          * the bulk-out maxpacket size */
1499                         bh->outreq->length = amount;
1500                         bh->bulk_out_intended_length = amount;
1501                         bh->outreq->short_not_ok = 1;
1502                         START_TRANSFER_OR(common, bulk_out, bh->outreq,
1503                                           &bh->outreq_busy, &bh->state)
1504                                 /* Don't know what to do if
1505                                  * common->fsg is NULL */
1506                                 return -EIO;
1507                         common->next_buffhd_to_fill = bh->next;
1508                         common->usb_amount_left -= amount;
1509                         continue;
1510                 }
1511
1512                 /* Otherwise wait for something to happen */
1513                 rc = sleep_thread(common);
1514                 if (rc)
1515                         return rc;
1516         }
1517         return 0;
1518 }
1519
1520
1521 static int finish_reply(struct fsg_common *common)
1522 {
1523         struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
1524         int                     rc = 0;
1525
1526         switch (common->data_dir) {
1527         case DATA_DIR_NONE:
1528                 break;                  /* Nothing to send */
1529
1530         /* If we don't know whether the host wants to read or write,
1531          * this must be CB or CBI with an unknown command.  We mustn't
1532          * try to send or receive any data.  So stall both bulk pipes
1533          * if we can and wait for a reset. */
1534         case DATA_DIR_UNKNOWN:
1535                 if (!common->can_stall) {
1536                         /* Nothing */
1537                 } else if (fsg_is_set(common)) {
1538                         fsg_set_halt(common->fsg, common->fsg->bulk_out);
1539                         rc = halt_bulk_in_endpoint(common->fsg);
1540                 } else {
1541                         /* Don't know what to do if common->fsg is NULL */
1542                         rc = -EIO;
1543                 }
1544                 break;
1545
1546         /* All but the last buffer of data must have already been sent */
1547         case DATA_DIR_TO_HOST:
1548                 if (common->data_size == 0) {
1549                         /* Nothing to send */
1550
1551                 /* If there's no residue, simply send the last buffer */
1552                 } else if (common->residue == 0) {
1553                         bh->inreq->zero = 0;
1554                         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1555                                           &bh->inreq_busy, &bh->state)
1556                                 return -EIO;
1557                         common->next_buffhd_to_fill = bh->next;
1558
1559                 /* For Bulk-only, if we're allowed to stall then send the
1560                  * short packet and halt the bulk-in endpoint.  If we can't
1561                  * stall, pad out the remaining data with 0's. */
1562                 } else if (common->can_stall) {
1563                         bh->inreq->zero = 1;
1564                         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1565                                           &bh->inreq_busy, &bh->state)
1566                                 /* Don't know what to do if
1567                                  * common->fsg is NULL */
1568                                 rc = -EIO;
1569                         common->next_buffhd_to_fill = bh->next;
1570                         if (common->fsg)
1571                                 rc = halt_bulk_in_endpoint(common->fsg);
1572                 } else if (fsg_is_set(common)) {
1573                         rc = pad_with_zeros(common->fsg);
1574                 } else {
1575                         /* Don't know what to do if common->fsg is NULL */
1576                         rc = -EIO;
1577                 }
1578                 break;
1579
1580         /* We have processed all we want from the data the host has sent.
1581          * There may still be outstanding bulk-out requests. */
1582         case DATA_DIR_FROM_HOST:
1583                 if (common->residue == 0) {
1584                         /* Nothing to receive */
1585
1586                 /* Did the host stop sending unexpectedly early? */
1587                 } else if (common->short_packet_received) {
1588                         raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1589                         rc = -EINTR;
1590
1591                 /* We haven't processed all the incoming data.  Even though
1592                  * we may be allowed to stall, doing so would cause a race.
1593                  * The controller may already have ACK'ed all the remaining
1594                  * bulk-out packets, in which case the host wouldn't see a
1595                  * STALL.  Not realizing the endpoint was halted, it wouldn't
1596                  * clear the halt -- leading to problems later on. */
1597 #if 0
1598                 } else if (common->can_stall) {
1599                         if (fsg_is_set(common))
1600                                 fsg_set_halt(common->fsg,
1601                                              common->fsg->bulk_out);
1602                         raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1603                         rc = -EINTR;
1604 #endif
1605
1606                 /* We can't stall.  Read in the excess data and throw it
1607                  * all away. */
1608                 } else {
1609                         rc = throw_away_data(common);
1610                 }
1611                 break;
1612         }
1613         return rc;
1614 }
1615
1616
1617 static int send_status(struct fsg_common *common)
1618 {
1619         struct fsg_lun          *curlun = &common->luns[common->lun];
1620         struct fsg_buffhd       *bh;
1621         struct bulk_cs_wrap     *csw;
1622         int                     rc;
1623         u8                      status = USB_STATUS_PASS;
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);
1630                 if (rc)
1631                         return rc;
1632         }
1633
1634         if (curlun)
1635                 sd = curlun->sense_data;
1636         else if (common->bad_lun_okay)
1637                 sd = SS_NO_SENSE;
1638         else
1639                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1640
1641         if (common->phase_error) {
1642                 DBG(common, "sending phase-error status\n");
1643                 status = USB_STATUS_PHASE_ERROR;
1644                 sd = SS_INVALID_COMMAND;
1645         } else if (sd != SS_NO_SENSE) {
1646                 DBG(common, "sending command-failure status\n");
1647                 status = USB_STATUS_FAIL;
1648                 VDBG(common, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1649                         "  info x%x\n",
1650                         SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1651         }
1652
1653         /* Store and send the Bulk-only CSW */
1654         csw = (void *)bh->buf;
1655
1656         csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1657         csw->Tag = common->tag;
1658         csw->Residue = cpu_to_le32(common->residue);
1659         csw->Status = status;
1660
1661         bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1662         bh->inreq->zero = 0;
1663         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1664                           &bh->inreq_busy, &bh->state)
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 /* Check whether the command is properly formed and whether its data size
1676  * and direction agree with the values we already have. */
1677 static int check_command(struct fsg_common *common, int cmnd_size,
1678                 enum data_direction data_dir, unsigned int mask,
1679                 int needs_medium, const char *name)
1680 {
1681         int                     i;
1682         int                     lun = common->cmnd[1] >> 5;
1683         static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
1684         char                    hdlen[20];
1685         struct fsg_lun          *curlun;
1686
1687         hdlen[0] = 0;
1688         if (common->data_dir != DATA_DIR_UNKNOWN)
1689                 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1690                                 common->data_size);
1691         VDBG(common, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
1692              name, cmnd_size, dirletter[(int) data_dir],
1693              common->data_size_from_cmnd, common->cmnd_size, hdlen);
1694
1695         /* We can't reply at all until we know the correct data direction
1696          * and size. */
1697         if (common->data_size_from_cmnd == 0)
1698                 data_dir = DATA_DIR_NONE;
1699         if (common->data_size < common->data_size_from_cmnd) {
1700                 /* Host data size < Device data size is a phase error.
1701                  * Carry out the command, but only transfer as much as
1702                  * we are allowed. */
1703                 common->data_size_from_cmnd = common->data_size;
1704                 common->phase_error = 1;
1705         }
1706         common->residue = common->data_size;
1707         common->usb_amount_left = common->data_size;
1708
1709         /* Conflicting data directions is a phase error */
1710         if (common->data_dir != data_dir
1711          && common->data_size_from_cmnd > 0) {
1712                 common->phase_error = 1;
1713                 return -EINVAL;
1714         }
1715
1716         /* Verify the length of the command itself */
1717         if (cmnd_size != common->cmnd_size) {
1718
1719                 /* Special case workaround: There are plenty of buggy SCSI
1720                  * implementations. Many have issues with cbw->Length
1721                  * field passing a wrong command size. For those cases we
1722                  * always try to work around the problem by using the length
1723                  * sent by the host side provided it is at least as large
1724                  * as the correct command length.
1725                  * Examples of such cases would be MS-Windows, which issues
1726                  * REQUEST SENSE with cbw->Length == 12 where it should
1727                  * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1728                  * REQUEST SENSE with cbw->Length == 10 where it should
1729                  * be 6 as well.
1730                  */
1731                 if (cmnd_size <= common->cmnd_size) {
1732                         DBG(common, "%s is buggy! Expected length %d "
1733                             "but we got %d\n", name,
1734                             cmnd_size, common->cmnd_size);
1735                         cmnd_size = common->cmnd_size;
1736                 } else {
1737                         common->phase_error = 1;
1738                         return -EINVAL;
1739                 }
1740         }
1741
1742         /* Check that the LUN values are consistent */
1743         if (common->lun != lun)
1744                 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1745                     common->lun, lun);
1746
1747         /* Check the LUN */
1748         if (common->lun >= 0 && common->lun < common->nluns) {
1749                 curlun = &common->luns[common->lun];
1750                 if (common->cmnd[0] != SC_REQUEST_SENSE) {
1751                         curlun->sense_data = SS_NO_SENSE;
1752                         curlun->info_valid = 0;
1753                 }
1754         } else {
1755                 curlun = NULL;
1756                 common->bad_lun_okay = 0;
1757
1758                 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
1759                  * to use unsupported LUNs; all others may not. */
1760                 if (common->cmnd[0] != SC_INQUIRY &&
1761                     common->cmnd[0] != SC_REQUEST_SENSE) {
1762                         DBG(common, "unsupported LUN %d\n", common->lun);
1763                         return -EINVAL;
1764                 }
1765         }
1766 #if 0
1767         /* If a unit attention condition exists, only INQUIRY and
1768          * REQUEST SENSE commands are allowed; anything else must fail. */
1769         if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1770                         common->cmnd[0] != SC_INQUIRY &&
1771                         common->cmnd[0] != SC_REQUEST_SENSE) {
1772                 curlun->sense_data = curlun->unit_attention_data;
1773                 curlun->unit_attention_data = SS_NO_SENSE;
1774                 return -EINVAL;
1775         }
1776 #endif
1777         /* Check that only command bytes listed in the mask are non-zero */
1778         common->cmnd[1] &= 0x1f;                        /* Mask away the LUN */
1779         for (i = 1; i < cmnd_size; ++i) {
1780                 if (common->cmnd[i] && !(mask & (1 << i))) {
1781                         if (curlun)
1782                                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1783                         return -EINVAL;
1784                 }
1785         }
1786
1787         return 0;
1788 }
1789
1790
1791 static int do_scsi_command(struct fsg_common *common)
1792 {
1793         struct fsg_buffhd       *bh;
1794         int                     rc;
1795         int                     reply = -EINVAL;
1796         int                     i;
1797         static char             unknown[16];
1798         struct fsg_lun          *curlun = &common->luns[common->lun];
1799
1800         dump_cdb(common);
1801
1802         /* Wait for the next buffer to become available for data or status */
1803         bh = common->next_buffhd_to_fill;
1804         common->next_buffhd_to_drain = bh;
1805         while (bh->state != BUF_STATE_EMPTY) {
1806                 rc = sleep_thread(common);
1807                 if (rc)
1808                         return rc;
1809         }
1810         common->phase_error = 0;
1811         common->short_packet_received = 0;
1812
1813         down_read(&common->filesem);    /* We're using the backing file */
1814         switch (common->cmnd[0]) {
1815
1816         case SC_INQUIRY:
1817                 common->data_size_from_cmnd = common->cmnd[4];
1818                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1819                                       (1<<4), 0,
1820                                       "INQUIRY");
1821                 if (reply == 0)
1822                         reply = do_inquiry(common, bh);
1823                 break;
1824
1825         case SC_MODE_SELECT_6:
1826                 common->data_size_from_cmnd = common->cmnd[4];
1827                 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1828                                       (1<<1) | (1<<4), 0,
1829                                       "MODE SELECT(6)");
1830                 if (reply == 0)
1831                         reply = do_mode_select(common, bh);
1832                 break;
1833
1834         case SC_MODE_SELECT_10:
1835                 common->data_size_from_cmnd =
1836                         get_unaligned_be16(&common->cmnd[7]);
1837                 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1838                                       (1<<1) | (3<<7), 0,
1839                                       "MODE SELECT(10)");
1840                 if (reply == 0)
1841                         reply = do_mode_select(common, bh);
1842                 break;
1843
1844         case SC_MODE_SENSE_6:
1845                 common->data_size_from_cmnd = common->cmnd[4];
1846                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1847                                       (1<<1) | (1<<2) | (1<<4), 0,
1848                                       "MODE SENSE(6)");
1849                 if (reply == 0)
1850                         reply = do_mode_sense(common, bh);
1851                 break;
1852
1853         case SC_MODE_SENSE_10:
1854                 common->data_size_from_cmnd =
1855                         get_unaligned_be16(&common->cmnd[7]);
1856                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1857                                       (1<<1) | (1<<2) | (3<<7), 0,
1858                                       "MODE SENSE(10)");
1859                 if (reply == 0)
1860                         reply = do_mode_sense(common, bh);
1861                 break;
1862
1863         case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
1864                 common->data_size_from_cmnd = 0;
1865                 reply = check_command(common, 6, DATA_DIR_NONE,
1866                                       (1<<4), 0,
1867                                       "PREVENT-ALLOW MEDIUM REMOVAL");
1868                 if (reply == 0)
1869                         reply = do_prevent_allow(common);
1870                 break;
1871
1872         case SC_READ_6:
1873                 i = common->cmnd[4];
1874                 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1875                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1876                                       (7<<1) | (1<<4), 1,
1877                                       "READ(6)");
1878                 if (reply == 0)
1879                         reply = do_read(common);
1880                 break;
1881
1882         case SC_READ_10:
1883                 common->data_size_from_cmnd =
1884                                 get_unaligned_be16(&common->cmnd[7]) << 9;
1885                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1886                                       (1<<1) | (0xf<<2) | (3<<7), 1,
1887                                       "READ(10)");
1888                 if (reply == 0)
1889                         reply = do_read(common);
1890                 break;
1891
1892         case SC_READ_12:
1893                 common->data_size_from_cmnd =
1894                                 get_unaligned_be32(&common->cmnd[6]) << 9;
1895                 reply = check_command(common, 12, DATA_DIR_TO_HOST,
1896                                       (1<<1) | (0xf<<2) | (0xf<<6), 1,
1897                                       "READ(12)");
1898                 if (reply == 0)
1899                         reply = do_read(common);
1900                 break;
1901
1902         case SC_READ_CAPACITY:
1903                 common->data_size_from_cmnd = 8;
1904                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1905                                       (0xf<<2) | (1<<8), 1,
1906                                       "READ CAPACITY");
1907                 if (reply == 0)
1908                         reply = do_read_capacity(common, bh);
1909                 break;
1910
1911         case SC_READ_HEADER:
1912                 if (!common->luns[common->lun].cdrom)
1913                         goto unknown_cmnd;
1914                 common->data_size_from_cmnd =
1915                         get_unaligned_be16(&common->cmnd[7]);
1916                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1917                                       (3<<7) | (0x1f<<1), 1,
1918                                       "READ HEADER");
1919                 if (reply == 0)
1920                         reply = do_read_header(common, bh);
1921                 break;
1922
1923         case SC_READ_TOC:
1924                 if (!common->luns[common->lun].cdrom)
1925                         goto unknown_cmnd;
1926                 common->data_size_from_cmnd =
1927                         get_unaligned_be16(&common->cmnd[7]);
1928                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1929                                       (7<<6) | (1<<1), 1,
1930                                       "READ TOC");
1931                 if (reply == 0)
1932                         reply = do_read_toc(common, bh);
1933                 break;
1934
1935         case SC_READ_FORMAT_CAPACITIES:
1936                 common->data_size_from_cmnd =
1937                         get_unaligned_be16(&common->cmnd[7]);
1938                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1939                                       (3<<7), 1,
1940                                       "READ FORMAT CAPACITIES");
1941                 if (reply == 0)
1942                         reply = do_read_format_capacities(common, bh);
1943                 break;
1944
1945         case SC_REQUEST_SENSE:
1946                 common->data_size_from_cmnd = common->cmnd[4];
1947                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1948                                       (1<<4), 0,
1949                                       "REQUEST SENSE");
1950                 if (reply == 0)
1951                         reply = do_request_sense(common, bh);
1952                 break;
1953
1954         case SC_START_STOP_UNIT:
1955                 common->data_size_from_cmnd = 0;
1956                 reply = check_command(common, 6, DATA_DIR_NONE,
1957                                       (1<<1) | (1<<4), 0,
1958                                       "START-STOP UNIT");
1959                 if (reply == 0)
1960                         reply = do_start_stop(common);
1961                 break;
1962
1963         case SC_SYNCHRONIZE_CACHE:
1964                 common->data_size_from_cmnd = 0;
1965                 reply = check_command(common, 10, DATA_DIR_NONE,
1966                                       (0xf<<2) | (3<<7), 1,
1967                                       "SYNCHRONIZE CACHE");
1968                 if (reply == 0)
1969                         reply = do_synchronize_cache(common);
1970                 break;
1971
1972         case SC_TEST_UNIT_READY:
1973                 common->data_size_from_cmnd = 0;
1974                 reply = check_command(common, 6, DATA_DIR_NONE,
1975                                 0, 1,
1976                                 "TEST UNIT READY");
1977                 break;
1978
1979         /* Although optional, this command is used by MS-Windows.  We
1980          * support a minimal version: BytChk must be 0. */
1981         case SC_VERIFY:
1982                 common->data_size_from_cmnd = 0;
1983                 reply = check_command(common, 10, DATA_DIR_NONE,
1984                                       (1<<1) | (0xf<<2) | (3<<7), 1,
1985                                       "VERIFY");
1986                 if (reply == 0)
1987                         reply = do_verify(common);
1988                 break;
1989
1990         case SC_WRITE_6:
1991                 i = common->cmnd[4];
1992                 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1993                 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1994                                       (7<<1) | (1<<4), 1,
1995                                       "WRITE(6)");
1996                 if (reply == 0)
1997                         reply = do_write(common);
1998                 break;
1999
2000         case SC_WRITE_10:
2001                 common->data_size_from_cmnd =
2002                                 get_unaligned_be16(&common->cmnd[7]) << 9;
2003                 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
2004                                       (1<<1) | (0xf<<2) | (3<<7), 1,
2005                                       "WRITE(10)");
2006                 if (reply == 0)
2007                         reply = do_write(common);
2008                 break;
2009
2010         case SC_WRITE_12:
2011                 common->data_size_from_cmnd =
2012                                 get_unaligned_be32(&common->cmnd[6]) << 9;
2013                 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
2014                                       (1<<1) | (0xf<<2) | (0xf<<6), 1,
2015                                       "WRITE(12)");
2016                 if (reply == 0)
2017                         reply = do_write(common);
2018                 break;
2019
2020         /* Some mandatory commands that we recognize but don't implement.
2021          * They don't mean much in this setting.  It's left as an exercise
2022          * for anyone interested to implement RESERVE and RELEASE in terms
2023          * of Posix locks. */
2024         case SC_FORMAT_UNIT:
2025         case SC_RELEASE:
2026         case SC_RESERVE:
2027         case SC_SEND_DIAGNOSTIC:
2028                 /* Fall through */
2029
2030         default:
2031 unknown_cmnd:
2032                 common->data_size_from_cmnd = 0;
2033                 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2034                 reply = check_command(common, common->cmnd_size,
2035                                       DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2036                 if (reply == 0) {
2037                         curlun->sense_data = SS_INVALID_COMMAND;
2038                         reply = -EINVAL;
2039                 }
2040                 break;
2041         }
2042         up_read(&common->filesem);
2043
2044         if (reply == -EINTR)
2045                 return -EINTR;
2046
2047         /* Set up the single reply buffer for finish_reply() */
2048         if (reply == -EINVAL)
2049                 reply = 0;              /* Error reply length */
2050         if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2051                 reply = min((u32) reply, common->data_size_from_cmnd);
2052                 bh->inreq->length = reply;
2053                 bh->state = BUF_STATE_FULL;
2054                 common->residue -= reply;
2055         }                               /* Otherwise it's already set */
2056
2057         return 0;
2058 }
2059
2060 /*-------------------------------------------------------------------------*/
2061
2062 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2063 {
2064         struct usb_request      *req = bh->outreq;
2065         struct fsg_bulk_cb_wrap *cbw = req->buf;
2066         struct fsg_common       *common = fsg->common;
2067
2068         /* Was this a real packet?  Should it be ignored? */
2069         if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2070                 return -EINVAL;
2071
2072         /* Is the CBW valid? */
2073         if (req->actual != USB_BULK_CB_WRAP_LEN ||
2074                         cbw->Signature != cpu_to_le32(
2075                                 USB_BULK_CB_SIG)) {
2076                 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2077                                 req->actual,
2078                                 le32_to_cpu(cbw->Signature));
2079
2080                 /* The Bulk-only spec says we MUST stall the IN endpoint
2081                  * (6.6.1), so it's unavoidable.  It also says we must
2082                  * retain this state until the next reset, but there's
2083                  * no way to tell the controller driver it should ignore
2084                  * Clear-Feature(HALT) requests.
2085                  *
2086                  * We aren't required to halt the OUT endpoint; instead
2087                  * we can simply accept and discard any data received
2088                  * until the next reset. */
2089                 wedge_bulk_in_endpoint(fsg);
2090                 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2091                 return -EINVAL;
2092         }
2093
2094         /* Is the CBW meaningful? */
2095         if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2096                         cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2097                 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2098                                 "cmdlen %u\n",
2099                                 cbw->Lun, cbw->Flags, cbw->Length);
2100
2101                 /* We can do anything we want here, so let's stall the
2102                  * bulk pipes if we are allowed to. */
2103                 if (common->can_stall) {
2104                         fsg_set_halt(fsg, fsg->bulk_out);
2105                         halt_bulk_in_endpoint(fsg);
2106                 }
2107                 return -EINVAL;
2108         }
2109
2110         /* Save the command for later */
2111         common->cmnd_size = cbw->Length;
2112         memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2113         if (cbw->Flags & USB_BULK_IN_FLAG)
2114                 common->data_dir = DATA_DIR_TO_HOST;
2115         else
2116                 common->data_dir = DATA_DIR_FROM_HOST;
2117         common->data_size = le32_to_cpu(cbw->DataTransferLength);
2118         if (common->data_size == 0)
2119                 common->data_dir = DATA_DIR_NONE;
2120         common->lun = cbw->Lun;
2121         common->tag = cbw->Tag;
2122         return 0;
2123 }
2124
2125
2126 static int get_next_command(struct fsg_common *common)
2127 {
2128         struct fsg_buffhd       *bh;
2129         int                     rc = 0;
2130
2131         /* Wait for the next buffer to become available */
2132         bh = common->next_buffhd_to_fill;
2133         while (bh->state != BUF_STATE_EMPTY) {
2134                 rc = sleep_thread(common);
2135                 if (rc)
2136                         return rc;
2137         }
2138
2139         /* Queue a request to read a Bulk-only CBW */
2140         set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2141         bh->outreq->short_not_ok = 1;
2142         START_TRANSFER_OR(common, bulk_out, bh->outreq,
2143                           &bh->outreq_busy, &bh->state)
2144                 /* Don't know what to do if common->fsg is NULL */
2145                 return -EIO;
2146
2147         /* We will drain the buffer in software, which means we
2148          * can reuse it for the next filling.  No need to advance
2149          * next_buffhd_to_fill. */
2150
2151         /* Wait for the CBW to arrive */
2152         while (bh->state != BUF_STATE_FULL) {
2153                 rc = sleep_thread(common);
2154                 if (rc)
2155                         return rc;
2156         }
2157
2158         rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2159         bh->state = BUF_STATE_EMPTY;
2160
2161         return rc;
2162 }
2163
2164
2165 /*-------------------------------------------------------------------------*/
2166
2167 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2168                 const struct usb_endpoint_descriptor *d)
2169 {
2170         int     rc;
2171
2172         ep->driver_data = common;
2173         rc = usb_ep_enable(ep, d);
2174         if (rc)
2175                 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2176         return rc;
2177 }
2178
2179 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2180                 struct usb_request **preq)
2181 {
2182         *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2183         if (*preq)
2184                 return 0;
2185         ERROR(common, "can't allocate request for %s\n", ep->name);
2186         return -ENOMEM;
2187 }
2188
2189 /* Reset interface setting and re-init endpoint state (toggle etc). */
2190 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2191 {
2192         const struct usb_endpoint_descriptor *d;
2193         struct fsg_dev *fsg;
2194         int i, rc = 0;
2195
2196         if (common->running)
2197                 DBG(common, "reset interface\n");
2198
2199 reset:
2200         /* Deallocate the requests */
2201         if (common->fsg) {
2202                 fsg = common->fsg;
2203
2204                 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2205                         struct fsg_buffhd *bh = &common->buffhds[i];
2206
2207                         if (bh->inreq) {
2208                                 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2209                                 bh->inreq = NULL;
2210                         }
2211                         if (bh->outreq) {
2212                                 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2213                                 bh->outreq = NULL;
2214                         }
2215                 }
2216
2217                 /* Disable the endpoints */
2218                 if (fsg->bulk_in_enabled) {
2219                         usb_ep_disable(fsg->bulk_in);
2220                         fsg->bulk_in_enabled = 0;
2221                 }
2222                 if (fsg->bulk_out_enabled) {
2223                         usb_ep_disable(fsg->bulk_out);
2224                         fsg->bulk_out_enabled = 0;
2225                 }
2226
2227                 common->fsg = NULL;
2228                 /* wake_up(&common->fsg_wait); */
2229         }
2230
2231         common->running = 0;
2232         if (!new_fsg || rc)
2233                 return rc;
2234
2235         common->fsg = new_fsg;
2236         fsg = common->fsg;
2237
2238         /* Enable the endpoints */
2239         d = fsg_ep_desc(common->gadget,
2240                         &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2241         rc = enable_endpoint(common, fsg->bulk_in, d);
2242         if (rc)
2243                 goto reset;
2244         fsg->bulk_in_enabled = 1;
2245
2246         d = fsg_ep_desc(common->gadget,
2247                         &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2248         rc = enable_endpoint(common, fsg->bulk_out, d);
2249         if (rc)
2250                 goto reset;
2251         fsg->bulk_out_enabled = 1;
2252         common->bulk_out_maxpacket =
2253                                 le16_to_cpu(get_unaligned(&d->wMaxPacketSize));
2254         clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2255
2256         /* Allocate the requests */
2257         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2258                 struct fsg_buffhd       *bh = &common->buffhds[i];
2259
2260                 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2261                 if (rc)
2262                         goto reset;
2263                 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2264                 if (rc)
2265                         goto reset;
2266                 bh->inreq->buf = bh->outreq->buf = bh->buf;
2267                 bh->inreq->context = bh->outreq->context = bh;
2268                 bh->inreq->complete = bulk_in_complete;
2269                 bh->outreq->complete = bulk_out_complete;
2270         }
2271
2272         common->running = 1;
2273
2274         return rc;
2275 }
2276
2277
2278 /****************************** ALT CONFIGS ******************************/
2279
2280
2281 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2282 {
2283         struct fsg_dev *fsg = fsg_from_func(f);
2284         fsg->common->new_fsg = fsg;
2285         raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2286         return 0;
2287 }
2288
2289 static void fsg_disable(struct usb_function *f)
2290 {
2291         struct fsg_dev *fsg = fsg_from_func(f);
2292         fsg->common->new_fsg = NULL;
2293         raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2294 }
2295
2296 /*-------------------------------------------------------------------------*/
2297
2298 static void handle_exception(struct fsg_common *common)
2299 {
2300         int                     i;
2301         struct fsg_buffhd       *bh;
2302         enum fsg_state          old_state;
2303         struct fsg_lun          *curlun;
2304         unsigned int            exception_req_tag;
2305
2306         /* Cancel all the pending transfers */
2307         if (common->fsg) {
2308                 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2309                         bh = &common->buffhds[i];
2310                         if (bh->inreq_busy)
2311                                 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2312                         if (bh->outreq_busy)
2313                                 usb_ep_dequeue(common->fsg->bulk_out,
2314                                                bh->outreq);
2315                 }
2316
2317                 /* Wait until everything is idle */
2318                 for (;;) {
2319                         int num_active = 0;
2320                         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2321                                 bh = &common->buffhds[i];
2322                                 num_active += bh->inreq_busy + bh->outreq_busy;
2323                         }
2324                         if (num_active == 0)
2325                                 break;
2326                         if (sleep_thread(common))
2327                                 return;
2328                 }
2329
2330                 /* Clear out the controller's fifos */
2331                 if (common->fsg->bulk_in_enabled)
2332                         usb_ep_fifo_flush(common->fsg->bulk_in);
2333                 if (common->fsg->bulk_out_enabled)
2334                         usb_ep_fifo_flush(common->fsg->bulk_out);
2335         }
2336
2337         /* Reset the I/O buffer states and pointers, the SCSI
2338          * state, and the exception.  Then invoke the handler. */
2339
2340         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2341                 bh = &common->buffhds[i];
2342                 bh->state = BUF_STATE_EMPTY;
2343         }
2344         common->next_buffhd_to_fill = &common->buffhds[0];
2345         common->next_buffhd_to_drain = &common->buffhds[0];
2346         exception_req_tag = common->exception_req_tag;
2347         old_state = common->state;
2348
2349         if (old_state == FSG_STATE_ABORT_BULK_OUT)
2350                 common->state = FSG_STATE_STATUS_PHASE;
2351         else {
2352                 for (i = 0; i < common->nluns; ++i) {
2353                         curlun = &common->luns[i];
2354                         curlun->sense_data = SS_NO_SENSE;
2355                         curlun->info_valid = 0;
2356                 }
2357                 common->state = FSG_STATE_IDLE;
2358         }
2359
2360         /* Carry out any extra actions required for the exception */
2361         switch (old_state) {
2362         case FSG_STATE_ABORT_BULK_OUT:
2363                 send_status(common);
2364
2365                 if (common->state == FSG_STATE_STATUS_PHASE)
2366                         common->state = FSG_STATE_IDLE;
2367                 break;
2368
2369         case FSG_STATE_RESET:
2370                 /* In case we were forced against our will to halt a
2371                  * bulk endpoint, clear the halt now.  (The SuperH UDC
2372                  * requires this.) */
2373                 if (!fsg_is_set(common))
2374                         break;
2375                 if (test_and_clear_bit(IGNORE_BULK_OUT,
2376                                        &common->fsg->atomic_bitflags))
2377                         usb_ep_clear_halt(common->fsg->bulk_in);
2378
2379                 if (common->ep0_req_tag == exception_req_tag)
2380                         ep0_queue(common);      /* Complete the status stage */
2381
2382                 break;
2383
2384         case FSG_STATE_CONFIG_CHANGE:
2385                 do_set_interface(common, common->new_fsg);
2386                 break;
2387
2388         case FSG_STATE_EXIT:
2389         case FSG_STATE_TERMINATED:
2390                 do_set_interface(common, NULL);         /* Free resources */
2391                 common->state = FSG_STATE_TERMINATED;   /* Stop the thread */
2392                 break;
2393
2394         case FSG_STATE_INTERFACE_CHANGE:
2395         case FSG_STATE_DISCONNECT:
2396         case FSG_STATE_COMMAND_PHASE:
2397         case FSG_STATE_DATA_PHASE:
2398         case FSG_STATE_STATUS_PHASE:
2399         case FSG_STATE_IDLE:
2400                 break;
2401         }
2402 }
2403
2404 /*-------------------------------------------------------------------------*/
2405
2406 int fsg_main_thread(void *common_)
2407 {
2408         int ret;
2409         struct fsg_common       *common = the_fsg_common;
2410         /* The main loop */
2411         do {
2412                 if (exception_in_progress(common)) {
2413                         handle_exception(common);
2414                         continue;
2415                 }
2416
2417                 if (!common->running) {
2418                         ret = sleep_thread(common);
2419                         if (ret)
2420                                 return ret;
2421
2422                         continue;
2423                 }
2424
2425                 ret = get_next_command(common);
2426                 if (ret)
2427                         return ret;
2428
2429                 if (!exception_in_progress(common))
2430                         common->state = FSG_STATE_DATA_PHASE;
2431
2432                 if (do_scsi_command(common) || finish_reply(common))
2433                         continue;
2434
2435                 if (!exception_in_progress(common))
2436                         common->state = FSG_STATE_STATUS_PHASE;
2437
2438                 if (send_status(common))
2439                         continue;
2440
2441                 if (!exception_in_progress(common))
2442                         common->state = FSG_STATE_IDLE;
2443         } while (0);
2444
2445         common->thread_task = NULL;
2446
2447         return 0;
2448 }
2449
2450 static void fsg_common_release(struct kref *ref);
2451
2452 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2453                                           struct usb_composite_dev *cdev)
2454 {
2455         struct usb_gadget *gadget = cdev->gadget;
2456         struct fsg_buffhd *bh;
2457         struct fsg_lun *curlun;
2458         int nluns, i, rc;
2459
2460         /* Find out how many LUNs there should be */
2461         nluns = 1;
2462         if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2463                 printf("invalid number of LUNs: %u\n", nluns);
2464                 return ERR_PTR(-EINVAL);
2465         }
2466
2467         /* Allocate? */
2468         if (!common) {
2469                 common = calloc(sizeof(*common), 1);
2470                 if (!common)
2471                         return ERR_PTR(-ENOMEM);
2472                 common->free_storage_on_release = 1;
2473         } else {
2474                 memset(common, 0, sizeof(*common));
2475                 common->free_storage_on_release = 0;
2476         }
2477
2478         common->ops = NULL;
2479         common->private_data = NULL;
2480
2481         common->gadget = gadget;
2482         common->ep0 = gadget->ep0;
2483         common->ep0req = cdev->req;
2484
2485         /* Maybe allocate device-global string IDs, and patch descriptors */
2486         if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2487                 rc = usb_string_id(cdev);
2488                 if (unlikely(rc < 0))
2489                         goto error_release;
2490                 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2491                 fsg_intf_desc.iInterface = rc;
2492         }
2493
2494         /* Create the LUNs, open their backing files, and register the
2495          * LUN devices in sysfs. */
2496         curlun = calloc(nluns, sizeof *curlun);
2497         if (!curlun) {
2498                 rc = -ENOMEM;
2499                 goto error_release;
2500         }
2501         common->nluns = nluns;
2502
2503         for (i = 0; i < nluns; i++) {
2504                 common->luns[i].removable = 1;
2505
2506                 rc = fsg_lun_open(&common->luns[i], "");
2507                 if (rc)
2508                         goto error_luns;
2509         }
2510         common->lun = 0;
2511
2512         /* Data buffers cyclic list */
2513         bh = common->buffhds;
2514
2515         i = FSG_NUM_BUFFERS;
2516         goto buffhds_first_it;
2517         do {
2518                 bh->next = bh + 1;
2519                 ++bh;
2520 buffhds_first_it:
2521                 bh->inreq_busy = 0;
2522                 bh->outreq_busy = 0;
2523                 bh->buf = memalign(CONFIG_SYS_CACHELINE_SIZE, FSG_BUFLEN);
2524                 if (unlikely(!bh->buf)) {
2525                         rc = -ENOMEM;
2526                         goto error_release;
2527                 }
2528         } while (--i);
2529         bh->next = common->buffhds;
2530
2531         snprintf(common->inquiry_string, sizeof common->inquiry_string,
2532                  "%-8s%-16s%04x",
2533                  "Linux   ",
2534                  "File-Store Gadget",
2535                  0xffff);
2536
2537         /* Some peripheral controllers are known not to be able to
2538          * halt bulk endpoints correctly.  If one of them is present,
2539          * disable stalls.
2540          */
2541
2542         /* Tell the thread to start working */
2543         common->thread_task =
2544                 kthread_create(fsg_main_thread, common,
2545                                OR(cfg->thread_name, "file-storage"));
2546         if (IS_ERR(common->thread_task)) {
2547                 rc = PTR_ERR(common->thread_task);
2548                 goto error_release;
2549         }
2550
2551 #undef OR
2552         /* Information */
2553         INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2554         INFO(common, "Number of LUNs=%d\n", common->nluns);
2555
2556         return common;
2557
2558 error_luns:
2559         common->nluns = i + 1;
2560 error_release:
2561         common->state = FSG_STATE_TERMINATED;   /* The thread is dead */
2562         /* Call fsg_common_release() directly, ref might be not
2563          * initialised */
2564         fsg_common_release(&common->ref);
2565         return ERR_PTR(rc);
2566 }
2567
2568 static void fsg_common_release(struct kref *ref)
2569 {
2570         struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2571
2572         /* If the thread isn't already dead, tell it to exit now */
2573         if (common->state != FSG_STATE_TERMINATED) {
2574                 raise_exception(common, FSG_STATE_EXIT);
2575                 wait_for_completion(&common->thread_notifier);
2576         }
2577
2578         if (likely(common->luns)) {
2579                 struct fsg_lun *lun = common->luns;
2580                 unsigned i = common->nluns;
2581
2582                 /* In error recovery common->nluns may be zero. */
2583                 for (; i; --i, ++lun)
2584                         fsg_lun_close(lun);
2585
2586                 kfree(common->luns);
2587         }
2588
2589         {
2590                 struct fsg_buffhd *bh = common->buffhds;
2591                 unsigned i = FSG_NUM_BUFFERS;
2592                 do {
2593                         kfree(bh->buf);
2594                 } while (++bh, --i);
2595         }
2596
2597         if (common->free_storage_on_release)
2598                 kfree(common);
2599 }
2600
2601
2602 /*-------------------------------------------------------------------------*/
2603
2604 /**
2605  * usb_copy_descriptors - copy a vector of USB descriptors
2606  * @src: null-terminated vector to copy
2607  * Context: initialization code, which may sleep
2608  *
2609  * This makes a copy of a vector of USB descriptors.  Its primary use
2610  * is to support usb_function objects which can have multiple copies,
2611  * each needing different descriptors.  Functions may have static
2612  * tables of descriptors, which are used as templates and customized
2613  * with identifiers (for interfaces, strings, endpoints, and more)
2614  * as needed by a given function instance.
2615  */
2616 struct usb_descriptor_header **
2617 usb_copy_descriptors(struct usb_descriptor_header **src)
2618 {
2619         struct usb_descriptor_header **tmp;
2620         unsigned bytes;
2621         unsigned n_desc;
2622         void *mem;
2623         struct usb_descriptor_header **ret;
2624
2625         /* count descriptors and their sizes; then add vector size */
2626         for (bytes = 0, n_desc = 0, tmp = src; *tmp; tmp++, n_desc++)
2627                 bytes += (*tmp)->bLength;
2628         bytes += (n_desc + 1) * sizeof(*tmp);
2629
2630         mem = memalign(CONFIG_SYS_CACHELINE_SIZE, bytes);
2631         if (!mem)
2632                 return NULL;
2633
2634         /* fill in pointers starting at "tmp",
2635          * to descriptors copied starting at "mem";
2636          * and return "ret"
2637          */
2638         tmp = mem;
2639         ret = mem;
2640         mem += (n_desc + 1) * sizeof(*tmp);
2641         while (*src) {
2642                 memcpy(mem, *src, (*src)->bLength);
2643                 *tmp = mem;
2644                 tmp++;
2645                 mem += (*src)->bLength;
2646                 src++;
2647         }
2648         *tmp = NULL;
2649
2650         return ret;
2651 }
2652
2653 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2654 {
2655         struct fsg_dev          *fsg = fsg_from_func(f);
2656
2657         DBG(fsg, "unbind\n");
2658         if (fsg->common->fsg == fsg) {
2659                 fsg->common->new_fsg = NULL;
2660                 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2661         }
2662
2663         free(fsg->function.descriptors);
2664         free(fsg->function.hs_descriptors);
2665         kfree(fsg);
2666 }
2667
2668 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2669 {
2670         struct fsg_dev          *fsg = fsg_from_func(f);
2671         struct usb_gadget       *gadget = c->cdev->gadget;
2672         int                     i;
2673         struct usb_ep           *ep;
2674         fsg->gadget = gadget;
2675
2676         /* New interface */
2677         i = usb_interface_id(c, f);
2678         if (i < 0)
2679                 return i;
2680         fsg_intf_desc.bInterfaceNumber = i;
2681         fsg->interface_number = i;
2682
2683         /* Find all the endpoints we will use */
2684         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2685         if (!ep)
2686                 goto autoconf_fail;
2687         ep->driver_data = fsg->common;  /* claim the endpoint */
2688         fsg->bulk_in = ep;
2689
2690         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2691         if (!ep)
2692                 goto autoconf_fail;
2693         ep->driver_data = fsg->common;  /* claim the endpoint */
2694         fsg->bulk_out = ep;
2695
2696         /* Copy descriptors */
2697         f->descriptors = usb_copy_descriptors(fsg_fs_function);
2698         if (unlikely(!f->descriptors))
2699                 return -ENOMEM;
2700
2701         if (gadget_is_dualspeed(gadget)) {
2702                 /* Assume endpoint addresses are the same for both speeds */
2703                 fsg_hs_bulk_in_desc.bEndpointAddress =
2704                         fsg_fs_bulk_in_desc.bEndpointAddress;
2705                 fsg_hs_bulk_out_desc.bEndpointAddress =
2706                         fsg_fs_bulk_out_desc.bEndpointAddress;
2707                 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
2708                 if (unlikely(!f->hs_descriptors)) {
2709                         free(f->descriptors);
2710                         return -ENOMEM;
2711                 }
2712         }
2713         return 0;
2714
2715 autoconf_fail:
2716         ERROR(fsg, "unable to autoconfigure all endpoints\n");
2717         return -ENOTSUPP;
2718 }
2719
2720
2721 /****************************** ADD FUNCTION ******************************/
2722
2723 static struct usb_gadget_strings *fsg_strings_array[] = {
2724         &fsg_stringtab,
2725         NULL,
2726 };
2727
2728 static int fsg_bind_config(struct usb_composite_dev *cdev,
2729                            struct usb_configuration *c,
2730                            struct fsg_common *common)
2731 {
2732         struct fsg_dev *fsg;
2733         int rc;
2734
2735         fsg = calloc(1, sizeof *fsg);
2736         if (!fsg)
2737                 return -ENOMEM;
2738         fsg->function.name        = FSG_DRIVER_DESC;
2739         fsg->function.strings     = fsg_strings_array;
2740         fsg->function.bind        = fsg_bind;
2741         fsg->function.unbind      = fsg_unbind;
2742         fsg->function.setup       = fsg_setup;
2743         fsg->function.set_alt     = fsg_set_alt;
2744         fsg->function.disable     = fsg_disable;
2745
2746         fsg->common               = common;
2747         common->fsg               = fsg;
2748         /* Our caller holds a reference to common structure so we
2749          * don't have to be worry about it being freed until we return
2750          * from this function.  So instead of incrementing counter now
2751          * and decrement in error recovery we increment it only when
2752          * call to usb_add_function() was successful. */
2753
2754         rc = usb_add_function(c, &fsg->function);
2755
2756         if (rc)
2757                 kfree(fsg);
2758
2759         return rc;
2760 }
2761
2762 int fsg_add(struct usb_configuration *c)
2763 {
2764         struct fsg_common *fsg_common;
2765
2766         fsg_common = fsg_common_init(NULL, c->cdev);
2767
2768         fsg_common->vendor_name = 0;
2769         fsg_common->product_name = 0;
2770         fsg_common->release = 0xffff;
2771
2772         fsg_common->ops = NULL;
2773         fsg_common->private_data = NULL;
2774
2775         the_fsg_common = fsg_common;
2776
2777         return fsg_bind_config(c->cdev, c, fsg_common);
2778 }
2779
2780 int fsg_init(struct ums *ums_dev)
2781 {
2782         ums = ums_dev;
2783
2784         return 0;
2785 }
2786
2787 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_ums, fsg_add);