sandbox: convert to common time functions
[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
247 #include <linux/err.h>
248 #include <linux/usb/ch9.h>
249 #include <linux/usb/gadget.h>
250 #include <usb_mass_storage.h>
251
252 #include <asm/unaligned.h>
253 #include <linux/usb/gadget.h>
254 #include <linux/usb/gadget.h>
255 #include <linux/usb/composite.h>
256 #include <usb/lin_gadget_compat.h>
257
258 /*------------------------------------------------------------------------*/
259
260 #define FSG_DRIVER_DESC "Mass Storage Function"
261 #define FSG_DRIVER_VERSION      "2012/06/5"
262
263 static const char fsg_string_interface[] = "Mass Storage";
264
265 #define FSG_NO_INTR_EP 1
266 #define FSG_NO_DEVICE_STRINGS    1
267 #define FSG_NO_OTG               1
268 #define FSG_NO_INTR_EP           1
269
270 #include "storage_common.c"
271
272 /*-------------------------------------------------------------------------*/
273
274 #define GFP_ATOMIC ((gfp_t) 0)
275 #define PAGE_CACHE_SHIFT        12
276 #define PAGE_CACHE_SIZE         (1 << PAGE_CACHE_SHIFT)
277 #define kthread_create(...)     __builtin_return_address(0)
278 #define wait_for_completion(...) do {} while (0)
279
280 struct kref {int x; };
281 struct completion {int x; };
282
283 inline void set_bit(int nr, volatile void *addr)
284 {
285         int     mask;
286         unsigned int *a = (unsigned int *) addr;
287
288         a += nr >> 5;
289         mask = 1 << (nr & 0x1f);
290         *a |= mask;
291 }
292
293 inline void clear_bit(int nr, volatile void *addr)
294 {
295         int     mask;
296         unsigned int *a = (unsigned int *) addr;
297
298         a += nr >> 5;
299         mask = 1 << (nr & 0x1f);
300         *a &= ~mask;
301 }
302
303 struct fsg_dev;
304 struct fsg_common;
305
306 /* Data shared by all the FSG instances. */
307 struct fsg_common {
308         struct usb_gadget       *gadget;
309         struct fsg_dev          *fsg, *new_fsg;
310
311         struct usb_ep           *ep0;           /* Copy of gadget->ep0 */
312         struct usb_request      *ep0req;        /* Copy of cdev->req */
313         unsigned int            ep0_req_tag;
314
315         struct fsg_buffhd       *next_buffhd_to_fill;
316         struct fsg_buffhd       *next_buffhd_to_drain;
317         struct fsg_buffhd       buffhds[FSG_NUM_BUFFERS];
318
319         int                     cmnd_size;
320         u8                      cmnd[MAX_COMMAND_SIZE];
321
322         unsigned int            nluns;
323         unsigned int            lun;
324         struct fsg_lun          luns[FSG_MAX_LUNS];
325
326         unsigned int            bulk_out_maxpacket;
327         enum fsg_state          state;          /* For exception handling */
328         unsigned int            exception_req_tag;
329
330         enum data_direction     data_dir;
331         u32                     data_size;
332         u32                     data_size_from_cmnd;
333         u32                     tag;
334         u32                     residue;
335         u32                     usb_amount_left;
336
337         unsigned int            can_stall:1;
338         unsigned int            free_storage_on_release:1;
339         unsigned int            phase_error:1;
340         unsigned int            short_packet_received:1;
341         unsigned int            bad_lun_okay:1;
342         unsigned int            running:1;
343
344         int                     thread_wakeup_needed;
345         struct completion       thread_notifier;
346         struct task_struct      *thread_task;
347
348         /* Callback functions. */
349         const struct fsg_operations     *ops;
350         /* Gadget's private data. */
351         void                    *private_data;
352
353         const char *vendor_name;                /*  8 characters or less */
354         const char *product_name;               /* 16 characters or less */
355         u16 release;
356
357         /* Vendor (8 chars), product (16 chars), release (4
358          * hexadecimal digits) and NUL byte */
359         char inquiry_string[8 + 16 + 4 + 1];
360
361         struct kref             ref;
362 };
363
364 struct fsg_config {
365         unsigned nluns;
366         struct fsg_lun_config {
367                 const char *filename;
368                 char ro;
369                 char removable;
370                 char cdrom;
371                 char nofua;
372         } luns[FSG_MAX_LUNS];
373
374         /* Callback functions. */
375         const struct fsg_operations     *ops;
376         /* Gadget's private data. */
377         void                    *private_data;
378
379         const char *vendor_name;                /*  8 characters or less */
380         const char *product_name;               /* 16 characters or less */
381
382         char                    can_stall;
383 };
384
385 struct fsg_dev {
386         struct usb_function     function;
387         struct usb_gadget       *gadget;        /* Copy of cdev->gadget */
388         struct fsg_common       *common;
389
390         u16                     interface_number;
391
392         unsigned int            bulk_in_enabled:1;
393         unsigned int            bulk_out_enabled:1;
394
395         unsigned long           atomic_bitflags;
396 #define IGNORE_BULK_OUT         0
397
398         struct usb_ep           *bulk_in;
399         struct usb_ep           *bulk_out;
400 };
401
402
403 static inline int __fsg_is_set(struct fsg_common *common,
404                                const char *func, unsigned line)
405 {
406         if (common->fsg)
407                 return 1;
408         ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
409         WARN_ON(1);
410         return 0;
411 }
412
413 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
414
415
416 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
417 {
418         return container_of(f, struct fsg_dev, function);
419 }
420
421
422 typedef void (*fsg_routine_t)(struct fsg_dev *);
423
424 static int exception_in_progress(struct fsg_common *common)
425 {
426         return common->state > FSG_STATE_IDLE;
427 }
428
429 /* Make bulk-out requests be divisible by the maxpacket size */
430 static void set_bulk_out_req_length(struct fsg_common *common,
431                 struct fsg_buffhd *bh, unsigned int length)
432 {
433         unsigned int    rem;
434
435         bh->bulk_out_intended_length = length;
436         rem = length % common->bulk_out_maxpacket;
437         if (rem > 0)
438                 length += common->bulk_out_maxpacket - rem;
439         bh->outreq->length = length;
440 }
441
442 /*-------------------------------------------------------------------------*/
443
444 struct ums_board_info                   *ums_info;
445 struct fsg_common *the_fsg_common;
446
447 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
448 {
449         const char      *name;
450
451         if (ep == fsg->bulk_in)
452                 name = "bulk-in";
453         else if (ep == fsg->bulk_out)
454                 name = "bulk-out";
455         else
456                 name = ep->name;
457         DBG(fsg, "%s set halt\n", name);
458         return usb_ep_set_halt(ep);
459 }
460
461 /*-------------------------------------------------------------------------*/
462
463 /* These routines may be called in process context or in_irq */
464
465 /* Caller must hold fsg->lock */
466 static void wakeup_thread(struct fsg_common *common)
467 {
468         common->thread_wakeup_needed = 1;
469 }
470
471 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
472 {
473         /* Do nothing if a higher-priority exception is already in progress.
474          * If a lower-or-equal priority exception is in progress, preempt it
475          * and notify the main thread by sending it a signal. */
476         if (common->state <= new_state) {
477                 common->exception_req_tag = common->ep0_req_tag;
478                 common->state = new_state;
479                 common->thread_wakeup_needed = 1;
480         }
481 }
482
483 /*-------------------------------------------------------------------------*/
484
485 static int ep0_queue(struct fsg_common *common)
486 {
487         int     rc;
488
489         rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
490         common->ep0->driver_data = common;
491         if (rc != 0 && rc != -ESHUTDOWN) {
492                 /* We can't do much more than wait for a reset */
493                 WARNING(common, "error in submission: %s --> %d\n",
494                         common->ep0->name, rc);
495         }
496         return rc;
497 }
498
499 /*-------------------------------------------------------------------------*/
500
501 /* Bulk and interrupt endpoint completion handlers.
502  * These always run in_irq. */
503
504 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
505 {
506         struct fsg_common       *common = ep->driver_data;
507         struct fsg_buffhd       *bh = req->context;
508
509         if (req->status || req->actual != req->length)
510                 DBG(common, "%s --> %d, %u/%u\n", __func__,
511                                 req->status, req->actual, req->length);
512         if (req->status == -ECONNRESET)         /* Request was cancelled */
513                 usb_ep_fifo_flush(ep);
514
515         /* Hold the lock while we update the request and buffer states */
516         bh->inreq_busy = 0;
517         bh->state = BUF_STATE_EMPTY;
518         wakeup_thread(common);
519 }
520
521 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
522 {
523         struct fsg_common       *common = ep->driver_data;
524         struct fsg_buffhd       *bh = req->context;
525
526         dump_msg(common, "bulk-out", req->buf, req->actual);
527         if (req->status || req->actual != bh->bulk_out_intended_length)
528                 DBG(common, "%s --> %d, %u/%u\n", __func__,
529                                 req->status, req->actual,
530                                 bh->bulk_out_intended_length);
531         if (req->status == -ECONNRESET)         /* Request was cancelled */
532                 usb_ep_fifo_flush(ep);
533
534         /* Hold the lock while we update the request and buffer states */
535         bh->outreq_busy = 0;
536         bh->state = BUF_STATE_FULL;
537         wakeup_thread(common);
538 }
539
540 /*-------------------------------------------------------------------------*/
541
542 /* Ep0 class-specific handlers.  These always run in_irq. */
543
544 static int fsg_setup(struct usb_function *f,
545                 const struct usb_ctrlrequest *ctrl)
546 {
547         struct fsg_dev          *fsg = fsg_from_func(f);
548         struct usb_request      *req = fsg->common->ep0req;
549         u16                     w_index = get_unaligned_le16(&ctrl->wIndex);
550         u16                     w_value = get_unaligned_le16(&ctrl->wValue);
551         u16                     w_length = get_unaligned_le16(&ctrl->wLength);
552
553         if (!fsg_is_set(fsg->common))
554                 return -EOPNOTSUPP;
555
556         switch (ctrl->bRequest) {
557
558         case USB_BULK_RESET_REQUEST:
559                 if (ctrl->bRequestType !=
560                     (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
561                         break;
562                 if (w_index != fsg->interface_number || w_value != 0)
563                         return -EDOM;
564
565                 /* Raise an exception to stop the current operation
566                  * and reinitialize our state. */
567                 DBG(fsg, "bulk reset request\n");
568                 raise_exception(fsg->common, FSG_STATE_RESET);
569                 return DELAYED_STATUS;
570
571         case USB_BULK_GET_MAX_LUN_REQUEST:
572                 if (ctrl->bRequestType !=
573                     (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
574                         break;
575                 if (w_index != fsg->interface_number || w_value != 0)
576                         return -EDOM;
577                 VDBG(fsg, "get max LUN\n");
578                 *(u8 *) req->buf = fsg->common->nluns - 1;
579
580                 /* Respond with data/status */
581                 req->length = min((u16)1, w_length);
582                 return ep0_queue(fsg->common);
583         }
584
585         VDBG(fsg,
586              "unknown class-specific control req "
587              "%02x.%02x v%04x i%04x l%u\n",
588              ctrl->bRequestType, ctrl->bRequest,
589              get_unaligned_le16(&ctrl->wValue), w_index, w_length);
590         return -EOPNOTSUPP;
591 }
592
593 /*-------------------------------------------------------------------------*/
594
595 /* All the following routines run in process context */
596
597 /* Use this for bulk or interrupt transfers, not ep0 */
598 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
599                 struct usb_request *req, int *pbusy,
600                 enum fsg_buffer_state *state)
601 {
602         int     rc;
603
604         if (ep == fsg->bulk_in)
605                 dump_msg(fsg, "bulk-in", req->buf, req->length);
606
607         *pbusy = 1;
608         *state = BUF_STATE_BUSY;
609         rc = usb_ep_queue(ep, req, GFP_KERNEL);
610         if (rc != 0) {
611                 *pbusy = 0;
612                 *state = BUF_STATE_EMPTY;
613
614                 /* We can't do much more than wait for a reset */
615
616                 /* Note: currently the net2280 driver fails zero-length
617                  * submissions if DMA is enabled. */
618                 if (rc != -ESHUTDOWN && !(rc == -EOPNOTSUPP &&
619                                                 req->length == 0))
620                         WARNING(fsg, "error in submission: %s --> %d\n",
621                                         ep->name, rc);
622         }
623 }
624
625 #define START_TRANSFER_OR(common, ep_name, req, pbusy, state)           \
626         if (fsg_is_set(common))                                         \
627                 start_transfer((common)->fsg, (common)->fsg->ep_name,   \
628                                req, pbusy, state);                      \
629         else
630
631 #define START_TRANSFER(common, ep_name, req, pbusy, state)              \
632         START_TRANSFER_OR(common, ep_name, req, pbusy, state) (void)0
633
634 static void busy_indicator(void)
635 {
636         static int state;
637
638         switch (state) {
639         case 0:
640                 puts("\r|"); break;
641         case 1:
642                 puts("\r/"); break;
643         case 2:
644                 puts("\r-"); break;
645         case 3:
646                 puts("\r\\"); break;
647         case 4:
648                 puts("\r|"); break;
649         case 5:
650                 puts("\r/"); break;
651         case 6:
652                 puts("\r-"); break;
653         case 7:
654                 puts("\r\\"); break;
655         default:
656                 state = 0;
657         }
658         if (state++ == 8)
659                 state = 0;
660 }
661
662 static int sleep_thread(struct fsg_common *common)
663 {
664         int     rc = 0;
665         int i = 0, k = 0;
666
667         /* Wait until a signal arrives or we are woken up */
668         for (;;) {
669                 if (common->thread_wakeup_needed)
670                         break;
671
672                 if (++i == 50000) {
673                         busy_indicator();
674                         i = 0;
675                         k++;
676                 }
677
678                 usb_gadget_handle_interrupts();
679         }
680         common->thread_wakeup_needed = 0;
681         return rc;
682 }
683
684 /*-------------------------------------------------------------------------*/
685
686 static int do_read(struct fsg_common *common)
687 {
688         struct fsg_lun          *curlun = &common->luns[common->lun];
689         u32                     lba;
690         struct fsg_buffhd       *bh;
691         int                     rc;
692         u32                     amount_left;
693         loff_t                  file_offset;
694         unsigned int            amount;
695         unsigned int            partial_page;
696         ssize_t                 nread;
697
698         /* Get the starting Logical Block Address and check that it's
699          * not too big */
700         if (common->cmnd[0] == SC_READ_6)
701                 lba = get_unaligned_be24(&common->cmnd[1]);
702         else {
703                 lba = get_unaligned_be32(&common->cmnd[2]);
704
705                 /* We allow DPO (Disable Page Out = don't save data in the
706                  * cache) and FUA (Force Unit Access = don't read from the
707                  * cache), but we don't implement them. */
708                 if ((common->cmnd[1] & ~0x18) != 0) {
709                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
710                         return -EINVAL;
711                 }
712         }
713         if (lba >= curlun->num_sectors) {
714                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
715                 return -EINVAL;
716         }
717         file_offset = ((loff_t) lba) << 9;
718
719         /* Carry out the file reads */
720         amount_left = common->data_size_from_cmnd;
721         if (unlikely(amount_left == 0))
722                 return -EIO;            /* No default reply */
723
724         for (;;) {
725
726                 /* Figure out how much we need to read:
727                  * Try to read the remaining amount.
728                  * But don't read more than the buffer size.
729                  * And don't try to read past the end of the file.
730                  * Finally, if we're not at a page boundary, don't read past
731                  *      the next page.
732                  * If this means reading 0 then we were asked to read past
733                  *      the end of file. */
734                 amount = min(amount_left, FSG_BUFLEN);
735                 partial_page = file_offset & (PAGE_CACHE_SIZE - 1);
736                 if (partial_page > 0)
737                         amount = min(amount, (unsigned int) PAGE_CACHE_SIZE -
738                                         partial_page);
739
740                 /* Wait for the next buffer to become available */
741                 bh = common->next_buffhd_to_fill;
742                 while (bh->state != BUF_STATE_EMPTY) {
743                         rc = sleep_thread(common);
744                         if (rc)
745                                 return rc;
746                 }
747
748                 /* If we were asked to read past the end of file,
749                  * end with an empty buffer. */
750                 if (amount == 0) {
751                         curlun->sense_data =
752                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
753                         curlun->info_valid = 1;
754                         bh->inreq->length = 0;
755                         bh->state = BUF_STATE_FULL;
756                         break;
757                 }
758
759                 /* Perform the read */
760                 nread = 0;
761                 rc = ums_info->read_sector(&(ums_info->ums_dev),
762                                            file_offset / SECTOR_SIZE,
763                                            amount / SECTOR_SIZE,
764                                            (char __user *)bh->buf);
765                 if (rc)
766                         return -EIO;
767                 nread = amount;
768
769                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
770                                 (unsigned long long) file_offset,
771                                 (int) nread);
772
773                 if (nread < 0) {
774                         LDBG(curlun, "error in file read: %d\n",
775                                         (int) nread);
776                         nread = 0;
777                 } else if (nread < amount) {
778                         LDBG(curlun, "partial file read: %d/%u\n",
779                                         (int) nread, amount);
780                         nread -= (nread & 511); /* Round down to a block */
781                 }
782                 file_offset  += nread;
783                 amount_left  -= nread;
784                 common->residue -= nread;
785                 bh->inreq->length = nread;
786                 bh->state = BUF_STATE_FULL;
787
788                 /* If an error occurred, report it and its position */
789                 if (nread < amount) {
790                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
791                         curlun->info_valid = 1;
792                         break;
793                 }
794
795                 if (amount_left == 0)
796                         break;          /* No more left to read */
797
798                 /* Send this buffer and go read some more */
799                 bh->inreq->zero = 0;
800                 START_TRANSFER_OR(common, bulk_in, bh->inreq,
801                                &bh->inreq_busy, &bh->state)
802                         /* Don't know what to do if
803                          * common->fsg is NULL */
804                         return -EIO;
805                 common->next_buffhd_to_fill = bh->next;
806         }
807
808         return -EIO;            /* No default reply */
809 }
810
811 /*-------------------------------------------------------------------------*/
812
813 static int do_write(struct fsg_common *common)
814 {
815         struct fsg_lun          *curlun = &common->luns[common->lun];
816         u32                     lba;
817         struct fsg_buffhd       *bh;
818         int                     get_some_more;
819         u32                     amount_left_to_req, amount_left_to_write;
820         loff_t                  usb_offset, file_offset;
821         unsigned int            amount;
822         unsigned int            partial_page;
823         ssize_t                 nwritten;
824         int                     rc;
825
826         if (curlun->ro) {
827                 curlun->sense_data = SS_WRITE_PROTECTED;
828                 return -EINVAL;
829         }
830
831         /* Get the starting Logical Block Address and check that it's
832          * not too big */
833         if (common->cmnd[0] == SC_WRITE_6)
834                 lba = get_unaligned_be24(&common->cmnd[1]);
835         else {
836                 lba = get_unaligned_be32(&common->cmnd[2]);
837
838                 /* We allow DPO (Disable Page Out = don't save data in the
839                  * cache) and FUA (Force Unit Access = write directly to the
840                  * medium).  We don't implement DPO; we implement FUA by
841                  * performing synchronous output. */
842                 if (common->cmnd[1] & ~0x18) {
843                         curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
844                         return -EINVAL;
845                 }
846         }
847         if (lba >= curlun->num_sectors) {
848                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
849                 return -EINVAL;
850         }
851
852         /* Carry out the file writes */
853         get_some_more = 1;
854         file_offset = usb_offset = ((loff_t) lba) << 9;
855         amount_left_to_req = common->data_size_from_cmnd;
856         amount_left_to_write = common->data_size_from_cmnd;
857
858         while (amount_left_to_write > 0) {
859
860                 /* Queue a request for more data from the host */
861                 bh = common->next_buffhd_to_fill;
862                 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
863
864                         /* Figure out how much we want to get:
865                          * Try to get the remaining amount.
866                          * But don't get more than the buffer size.
867                          * And don't try to go past the end of the file.
868                          * If we're not at a page boundary,
869                          *      don't go past the next page.
870                          * If this means getting 0, then we were asked
871                          *      to write past the end of file.
872                          * Finally, round down to a block boundary. */
873                         amount = min(amount_left_to_req, FSG_BUFLEN);
874                         partial_page = usb_offset & (PAGE_CACHE_SIZE - 1);
875                         if (partial_page > 0)
876                                 amount = min(amount,
877         (unsigned int) PAGE_CACHE_SIZE - partial_page);
878
879                         if (amount == 0) {
880                                 get_some_more = 0;
881                                 curlun->sense_data =
882                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
883                                 curlun->info_valid = 1;
884                                 continue;
885                         }
886                         amount -= (amount & 511);
887                         if (amount == 0) {
888
889                                 /* Why were we were asked to transfer a
890                                  * partial block? */
891                                 get_some_more = 0;
892                                 continue;
893                         }
894
895                         /* Get the next buffer */
896                         usb_offset += amount;
897                         common->usb_amount_left -= amount;
898                         amount_left_to_req -= amount;
899                         if (amount_left_to_req == 0)
900                                 get_some_more = 0;
901
902                         /* amount is always divisible by 512, hence by
903                          * the bulk-out maxpacket size */
904                         bh->outreq->length = amount;
905                         bh->bulk_out_intended_length = amount;
906                         bh->outreq->short_not_ok = 1;
907                         START_TRANSFER_OR(common, bulk_out, bh->outreq,
908                                           &bh->outreq_busy, &bh->state)
909                                 /* Don't know what to do if
910                                  * common->fsg is NULL */
911                                 return -EIO;
912                         common->next_buffhd_to_fill = bh->next;
913                         continue;
914                 }
915
916                 /* Write the received data to the backing file */
917                 bh = common->next_buffhd_to_drain;
918                 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
919                         break;                  /* We stopped early */
920                 if (bh->state == BUF_STATE_FULL) {
921                         common->next_buffhd_to_drain = bh->next;
922                         bh->state = BUF_STATE_EMPTY;
923
924                         /* Did something go wrong with the transfer? */
925                         if (bh->outreq->status != 0) {
926                                 curlun->sense_data = SS_COMMUNICATION_FAILURE;
927                                 curlun->info_valid = 1;
928                                 break;
929                         }
930
931                         amount = bh->outreq->actual;
932
933                         /* Perform the write */
934                         rc = ums_info->write_sector(&(ums_info->ums_dev),
935                                                file_offset / SECTOR_SIZE,
936                                                amount / SECTOR_SIZE,
937                                                (char __user *)bh->buf);
938                         if (rc)
939                                 return -EIO;
940                         nwritten = amount;
941
942                         VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
943                                         (unsigned long long) file_offset,
944                                         (int) nwritten);
945
946                         if (nwritten < 0) {
947                                 LDBG(curlun, "error in file write: %d\n",
948                                                 (int) nwritten);
949                                 nwritten = 0;
950                         } else if (nwritten < amount) {
951                                 LDBG(curlun, "partial file write: %d/%u\n",
952                                                 (int) nwritten, amount);
953                                 nwritten -= (nwritten & 511);
954                                 /* Round down to a block */
955                         }
956                         file_offset += nwritten;
957                         amount_left_to_write -= nwritten;
958                         common->residue -= nwritten;
959
960                         /* If an error occurred, report it and its position */
961                         if (nwritten < amount) {
962                                 curlun->sense_data = SS_WRITE_ERROR;
963                                 curlun->info_valid = 1;
964                                 break;
965                         }
966
967                         /* Did the host decide to stop early? */
968                         if (bh->outreq->actual != bh->outreq->length) {
969                                 common->short_packet_received = 1;
970                                 break;
971                         }
972                         continue;
973                 }
974
975                 /* Wait for something to happen */
976                 rc = sleep_thread(common);
977                 if (rc)
978                         return rc;
979         }
980
981         return -EIO;            /* No default reply */
982 }
983
984 /*-------------------------------------------------------------------------*/
985
986 static int do_synchronize_cache(struct fsg_common *common)
987 {
988         return 0;
989 }
990
991 /*-------------------------------------------------------------------------*/
992
993 static int do_verify(struct fsg_common *common)
994 {
995         struct fsg_lun          *curlun = &common->luns[common->lun];
996         u32                     lba;
997         u32                     verification_length;
998         struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
999         loff_t                  file_offset;
1000         u32                     amount_left;
1001         unsigned int            amount;
1002         ssize_t                 nread;
1003         int                     rc;
1004
1005         /* Get the starting Logical Block Address and check that it's
1006          * not too big */
1007         lba = get_unaligned_be32(&common->cmnd[2]);
1008         if (lba >= curlun->num_sectors) {
1009                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1010                 return -EINVAL;
1011         }
1012
1013         /* We allow DPO (Disable Page Out = don't save data in the
1014          * cache) but we don't implement it. */
1015         if (common->cmnd[1] & ~0x10) {
1016                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1017                 return -EINVAL;
1018         }
1019
1020         verification_length = get_unaligned_be16(&common->cmnd[7]);
1021         if (unlikely(verification_length == 0))
1022                 return -EIO;            /* No default reply */
1023
1024         /* Prepare to carry out the file verify */
1025         amount_left = verification_length << 9;
1026         file_offset = ((loff_t) lba) << 9;
1027
1028         /* Write out all the dirty buffers before invalidating them */
1029
1030         /* Just try to read the requested blocks */
1031         while (amount_left > 0) {
1032
1033                 /* Figure out how much we need to read:
1034                  * Try to read the remaining amount, but not more than
1035                  * the buffer size.
1036                  * And don't try to read past the end of the file.
1037                  * If this means reading 0 then we were asked to read
1038                  * past the end of file. */
1039                 amount = min(amount_left, FSG_BUFLEN);
1040                 if (amount == 0) {
1041                         curlun->sense_data =
1042                                         SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1043                         curlun->info_valid = 1;
1044                         break;
1045                 }
1046
1047                 /* Perform the read */
1048                 nread = 0;
1049                 rc = ums_info->read_sector(&(ums_info->ums_dev),
1050                                            file_offset / SECTOR_SIZE,
1051                                            amount / SECTOR_SIZE,
1052                                            (char __user *)bh->buf);
1053                 if (rc)
1054                         return -EIO;
1055                 nread = amount;
1056
1057                 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1058                                 (unsigned long long) file_offset,
1059                                 (int) nread);
1060                 if (nread < 0) {
1061                         LDBG(curlun, "error in file verify: %d\n",
1062                                         (int) nread);
1063                         nread = 0;
1064                 } else if (nread < amount) {
1065                         LDBG(curlun, "partial file verify: %d/%u\n",
1066                                         (int) nread, amount);
1067                         nread -= (nread & 511); /* Round down to a sector */
1068                 }
1069                 if (nread == 0) {
1070                         curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1071                         curlun->info_valid = 1;
1072                         break;
1073                 }
1074                 file_offset += nread;
1075                 amount_left -= nread;
1076         }
1077         return 0;
1078 }
1079
1080 /*-------------------------------------------------------------------------*/
1081
1082 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1083 {
1084         struct fsg_lun *curlun = &common->luns[common->lun];
1085         static const char vendor_id[] = "Linux   ";
1086         u8      *buf = (u8 *) bh->buf;
1087
1088         if (!curlun) {          /* Unsupported LUNs are okay */
1089                 common->bad_lun_okay = 1;
1090                 memset(buf, 0, 36);
1091                 buf[0] = 0x7f;          /* Unsupported, no device-type */
1092                 buf[4] = 31;            /* Additional length */
1093                 return 36;
1094         }
1095
1096         memset(buf, 0, 8);
1097         buf[0] = TYPE_DISK;
1098         buf[2] = 2;             /* ANSI SCSI level 2 */
1099         buf[3] = 2;             /* SCSI-2 INQUIRY data format */
1100         buf[4] = 31;            /* Additional length */
1101                                 /* No special options */
1102         sprintf((char *) (buf + 8), "%-8s%-16s%04x", (char*) vendor_id ,
1103                         ums_info->name, (u16) 0xffff);
1104
1105         return 36;
1106 }
1107
1108
1109 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1110 {
1111         struct fsg_lun  *curlun = &common->luns[common->lun];
1112         u8              *buf = (u8 *) bh->buf;
1113         u32             sd, sdinfo;
1114         int             valid;
1115
1116         /*
1117          * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1118          *
1119          * If a REQUEST SENSE command is received from an initiator
1120          * with a pending unit attention condition (before the target
1121          * generates the contingent allegiance condition), then the
1122          * target shall either:
1123          *   a) report any pending sense data and preserve the unit
1124          *      attention condition on the logical unit, or,
1125          *   b) report the unit attention condition, may discard any
1126          *      pending sense data, and clear the unit attention
1127          *      condition on the logical unit for that initiator.
1128          *
1129          * FSG normally uses option a); enable this code to use option b).
1130          */
1131 #if 0
1132         if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1133                 curlun->sense_data = curlun->unit_attention_data;
1134                 curlun->unit_attention_data = SS_NO_SENSE;
1135         }
1136 #endif
1137
1138         if (!curlun) {          /* Unsupported LUNs are okay */
1139                 common->bad_lun_okay = 1;
1140                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1141                 sdinfo = 0;
1142                 valid = 0;
1143         } else {
1144                 sd = curlun->sense_data;
1145                 valid = curlun->info_valid << 7;
1146                 curlun->sense_data = SS_NO_SENSE;
1147                 curlun->info_valid = 0;
1148         }
1149
1150         memset(buf, 0, 18);
1151         buf[0] = valid | 0x70;                  /* Valid, current error */
1152         buf[2] = SK(sd);
1153         put_unaligned_be32(sdinfo, &buf[3]);    /* Sense information */
1154         buf[7] = 18 - 8;                        /* Additional sense length */
1155         buf[12] = ASC(sd);
1156         buf[13] = ASCQ(sd);
1157         return 18;
1158 }
1159
1160 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1161 {
1162         struct fsg_lun  *curlun = &common->luns[common->lun];
1163         u32             lba = get_unaligned_be32(&common->cmnd[2]);
1164         int             pmi = common->cmnd[8];
1165         u8              *buf = (u8 *) bh->buf;
1166
1167         /* Check the PMI and LBA fields */
1168         if (pmi > 1 || (pmi == 0 && lba != 0)) {
1169                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1170                 return -EINVAL;
1171         }
1172
1173         put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1174                                                 /* Max logical block */
1175         put_unaligned_be32(512, &buf[4]);       /* Block length */
1176         return 8;
1177 }
1178
1179 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1180 {
1181         struct fsg_lun  *curlun = &common->luns[common->lun];
1182         int             msf = common->cmnd[1] & 0x02;
1183         u32             lba = get_unaligned_be32(&common->cmnd[2]);
1184         u8              *buf = (u8 *) bh->buf;
1185
1186         if (common->cmnd[1] & ~0x02) {          /* Mask away MSF */
1187                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1188                 return -EINVAL;
1189         }
1190         if (lba >= curlun->num_sectors) {
1191                 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1192                 return -EINVAL;
1193         }
1194
1195         memset(buf, 0, 8);
1196         buf[0] = 0x01;          /* 2048 bytes of user data, rest is EC */
1197         store_cdrom_address(&buf[4], msf, lba);
1198         return 8;
1199 }
1200
1201
1202 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1203 {
1204         struct fsg_lun  *curlun = &common->luns[common->lun];
1205         int             msf = common->cmnd[1] & 0x02;
1206         int             start_track = common->cmnd[6];
1207         u8              *buf = (u8 *) bh->buf;
1208
1209         if ((common->cmnd[1] & ~0x02) != 0 ||   /* Mask away MSF */
1210                         start_track > 1) {
1211                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1212                 return -EINVAL;
1213         }
1214
1215         memset(buf, 0, 20);
1216         buf[1] = (20-2);                /* TOC data length */
1217         buf[2] = 1;                     /* First track number */
1218         buf[3] = 1;                     /* Last track number */
1219         buf[5] = 0x16;                  /* Data track, copying allowed */
1220         buf[6] = 0x01;                  /* Only track is number 1 */
1221         store_cdrom_address(&buf[8], msf, 0);
1222
1223         buf[13] = 0x16;                 /* Lead-out track is data */
1224         buf[14] = 0xAA;                 /* Lead-out track number */
1225         store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1226
1227         return 20;
1228 }
1229
1230 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1231 {
1232         struct fsg_lun  *curlun = &common->luns[common->lun];
1233         int             mscmnd = common->cmnd[0];
1234         u8              *buf = (u8 *) bh->buf;
1235         u8              *buf0 = buf;
1236         int             pc, page_code;
1237         int             changeable_values, all_pages;
1238         int             valid_page = 0;
1239         int             len, limit;
1240
1241         if ((common->cmnd[1] & ~0x08) != 0) {   /* Mask away DBD */
1242                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1243                 return -EINVAL;
1244         }
1245         pc = common->cmnd[2] >> 6;
1246         page_code = common->cmnd[2] & 0x3f;
1247         if (pc == 3) {
1248                 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1249                 return -EINVAL;
1250         }
1251         changeable_values = (pc == 1);
1252         all_pages = (page_code == 0x3f);
1253
1254         /* Write the mode parameter header.  Fixed values are: default
1255          * medium type, no cache control (DPOFUA), and no block descriptors.
1256          * The only variable value is the WriteProtect bit.  We will fill in
1257          * the mode data length later. */
1258         memset(buf, 0, 8);
1259         if (mscmnd == SC_MODE_SENSE_6) {
1260                 buf[2] = (curlun->ro ? 0x80 : 0x00);            /* WP, DPOFUA */
1261                 buf += 4;
1262                 limit = 255;
1263         } else {                        /* SC_MODE_SENSE_10 */
1264                 buf[3] = (curlun->ro ? 0x80 : 0x00);            /* WP, DPOFUA */
1265                 buf += 8;
1266                 limit = 65535;          /* Should really be FSG_BUFLEN */
1267         }
1268
1269         /* No block descriptors */
1270
1271         /* The mode pages, in numerical order.  The only page we support
1272          * is the Caching page. */
1273         if (page_code == 0x08 || all_pages) {
1274                 valid_page = 1;
1275                 buf[0] = 0x08;          /* Page code */
1276                 buf[1] = 10;            /* Page length */
1277                 memset(buf+2, 0, 10);   /* None of the fields are changeable */
1278
1279                 if (!changeable_values) {
1280                         buf[2] = 0x04;  /* Write cache enable, */
1281                                         /* Read cache not disabled */
1282                                         /* No cache retention priorities */
1283                         put_unaligned_be16(0xffff, &buf[4]);
1284                                         /* Don't disable prefetch */
1285                                         /* Minimum prefetch = 0 */
1286                         put_unaligned_be16(0xffff, &buf[8]);
1287                                         /* Maximum prefetch */
1288                         put_unaligned_be16(0xffff, &buf[10]);
1289                                         /* Maximum prefetch ceiling */
1290                 }
1291                 buf += 12;
1292         }
1293
1294         /* Check that a valid page was requested and the mode data length
1295          * isn't too long. */
1296         len = buf - buf0;
1297         if (!valid_page || len > limit) {
1298                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1299                 return -EINVAL;
1300         }
1301
1302         /*  Store the mode data length */
1303         if (mscmnd == SC_MODE_SENSE_6)
1304                 buf0[0] = len - 1;
1305         else
1306                 put_unaligned_be16(len - 2, buf0);
1307         return len;
1308 }
1309
1310
1311 static int do_start_stop(struct fsg_common *common)
1312 {
1313         struct fsg_lun  *curlun = &common->luns[common->lun];
1314
1315         if (!curlun) {
1316                 return -EINVAL;
1317         } else if (!curlun->removable) {
1318                 curlun->sense_data = SS_INVALID_COMMAND;
1319                 return -EINVAL;
1320         }
1321
1322         return 0;
1323 }
1324
1325 static int do_prevent_allow(struct fsg_common *common)
1326 {
1327         struct fsg_lun  *curlun = &common->luns[common->lun];
1328         int             prevent;
1329
1330         if (!curlun->removable) {
1331                 curlun->sense_data = SS_INVALID_COMMAND;
1332                 return -EINVAL;
1333         }
1334
1335         prevent = common->cmnd[4] & 0x01;
1336         if ((common->cmnd[4] & ~0x01) != 0) {   /* Mask away Prevent */
1337                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1338                 return -EINVAL;
1339         }
1340
1341         if (curlun->prevent_medium_removal && !prevent)
1342                 fsg_lun_fsync_sub(curlun);
1343         curlun->prevent_medium_removal = prevent;
1344         return 0;
1345 }
1346
1347
1348 static int do_read_format_capacities(struct fsg_common *common,
1349                         struct fsg_buffhd *bh)
1350 {
1351         struct fsg_lun  *curlun = &common->luns[common->lun];
1352         u8              *buf = (u8 *) bh->buf;
1353
1354         buf[0] = buf[1] = buf[2] = 0;
1355         buf[3] = 8;     /* Only the Current/Maximum Capacity Descriptor */
1356         buf += 4;
1357
1358         put_unaligned_be32(curlun->num_sectors, &buf[0]);
1359                                                 /* Number of blocks */
1360         put_unaligned_be32(512, &buf[4]);       /* Block length */
1361         buf[4] = 0x02;                          /* Current capacity */
1362         return 12;
1363 }
1364
1365
1366 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1367 {
1368         struct fsg_lun  *curlun = &common->luns[common->lun];
1369
1370         /* We don't support MODE SELECT */
1371         if (curlun)
1372                 curlun->sense_data = SS_INVALID_COMMAND;
1373         return -EINVAL;
1374 }
1375
1376
1377 /*-------------------------------------------------------------------------*/
1378
1379 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1380 {
1381         int     rc;
1382
1383         rc = fsg_set_halt(fsg, fsg->bulk_in);
1384         if (rc == -EAGAIN)
1385                 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1386         while (rc != 0) {
1387                 if (rc != -EAGAIN) {
1388                         WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1389                         rc = 0;
1390                         break;
1391                 }
1392
1393                 rc = usb_ep_set_halt(fsg->bulk_in);
1394         }
1395         return rc;
1396 }
1397
1398 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1399 {
1400         int     rc;
1401
1402         DBG(fsg, "bulk-in set wedge\n");
1403         rc = 0; /* usb_ep_set_wedge(fsg->bulk_in); */
1404         if (rc == -EAGAIN)
1405                 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1406         while (rc != 0) {
1407                 if (rc != -EAGAIN) {
1408                         WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1409                         rc = 0;
1410                         break;
1411                 }
1412         }
1413         return rc;
1414 }
1415
1416 static int pad_with_zeros(struct fsg_dev *fsg)
1417 {
1418         struct fsg_buffhd       *bh = fsg->common->next_buffhd_to_fill;
1419         u32                     nkeep = bh->inreq->length;
1420         u32                     nsend;
1421         int                     rc;
1422
1423         bh->state = BUF_STATE_EMPTY;            /* For the first iteration */
1424         fsg->common->usb_amount_left = nkeep + fsg->common->residue;
1425         while (fsg->common->usb_amount_left > 0) {
1426
1427                 /* Wait for the next buffer to be free */
1428                 while (bh->state != BUF_STATE_EMPTY) {
1429                         rc = sleep_thread(fsg->common);
1430                         if (rc)
1431                                 return rc;
1432                 }
1433
1434                 nsend = min(fsg->common->usb_amount_left, FSG_BUFLEN);
1435                 memset(bh->buf + nkeep, 0, nsend - nkeep);
1436                 bh->inreq->length = nsend;
1437                 bh->inreq->zero = 0;
1438                 start_transfer(fsg, fsg->bulk_in, bh->inreq,
1439                                 &bh->inreq_busy, &bh->state);
1440                 bh = fsg->common->next_buffhd_to_fill = bh->next;
1441                 fsg->common->usb_amount_left -= nsend;
1442                 nkeep = 0;
1443         }
1444         return 0;
1445 }
1446
1447 static int throw_away_data(struct fsg_common *common)
1448 {
1449         struct fsg_buffhd       *bh;
1450         u32                     amount;
1451         int                     rc;
1452
1453         for (bh = common->next_buffhd_to_drain;
1454              bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1455              bh = common->next_buffhd_to_drain) {
1456
1457                 /* Throw away the data in a filled buffer */
1458                 if (bh->state == BUF_STATE_FULL) {
1459                         bh->state = BUF_STATE_EMPTY;
1460                         common->next_buffhd_to_drain = bh->next;
1461
1462                         /* A short packet or an error ends everything */
1463                         if (bh->outreq->actual != bh->outreq->length ||
1464                                         bh->outreq->status != 0) {
1465                                 raise_exception(common,
1466                                                 FSG_STATE_ABORT_BULK_OUT);
1467                                 return -EINTR;
1468                         }
1469                         continue;
1470                 }
1471
1472                 /* Try to submit another request if we need one */
1473                 bh = common->next_buffhd_to_fill;
1474                 if (bh->state == BUF_STATE_EMPTY
1475                  && common->usb_amount_left > 0) {
1476                         amount = min(common->usb_amount_left, FSG_BUFLEN);
1477
1478                         /* amount is always divisible by 512, hence by
1479                          * the bulk-out maxpacket size */
1480                         bh->outreq->length = amount;
1481                         bh->bulk_out_intended_length = amount;
1482                         bh->outreq->short_not_ok = 1;
1483                         START_TRANSFER_OR(common, bulk_out, bh->outreq,
1484                                           &bh->outreq_busy, &bh->state)
1485                                 /* Don't know what to do if
1486                                  * common->fsg is NULL */
1487                                 return -EIO;
1488                         common->next_buffhd_to_fill = bh->next;
1489                         common->usb_amount_left -= amount;
1490                         continue;
1491                 }
1492
1493                 /* Otherwise wait for something to happen */
1494                 rc = sleep_thread(common);
1495                 if (rc)
1496                         return rc;
1497         }
1498         return 0;
1499 }
1500
1501
1502 static int finish_reply(struct fsg_common *common)
1503 {
1504         struct fsg_buffhd       *bh = common->next_buffhd_to_fill;
1505         int                     rc = 0;
1506
1507         switch (common->data_dir) {
1508         case DATA_DIR_NONE:
1509                 break;                  /* Nothing to send */
1510
1511         /* If we don't know whether the host wants to read or write,
1512          * this must be CB or CBI with an unknown command.  We mustn't
1513          * try to send or receive any data.  So stall both bulk pipes
1514          * if we can and wait for a reset. */
1515         case DATA_DIR_UNKNOWN:
1516                 if (!common->can_stall) {
1517                         /* Nothing */
1518                 } else if (fsg_is_set(common)) {
1519                         fsg_set_halt(common->fsg, common->fsg->bulk_out);
1520                         rc = halt_bulk_in_endpoint(common->fsg);
1521                 } else {
1522                         /* Don't know what to do if common->fsg is NULL */
1523                         rc = -EIO;
1524                 }
1525                 break;
1526
1527         /* All but the last buffer of data must have already been sent */
1528         case DATA_DIR_TO_HOST:
1529                 if (common->data_size == 0) {
1530                         /* Nothing to send */
1531
1532                 /* If there's no residue, simply send the last buffer */
1533                 } else if (common->residue == 0) {
1534                         bh->inreq->zero = 0;
1535                         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1536                                           &bh->inreq_busy, &bh->state)
1537                                 return -EIO;
1538                         common->next_buffhd_to_fill = bh->next;
1539
1540                 /* For Bulk-only, if we're allowed to stall then send the
1541                  * short packet and halt the bulk-in endpoint.  If we can't
1542                  * stall, pad out the remaining data with 0's. */
1543                 } else if (common->can_stall) {
1544                         bh->inreq->zero = 1;
1545                         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1546                                           &bh->inreq_busy, &bh->state)
1547                                 /* Don't know what to do if
1548                                  * common->fsg is NULL */
1549                                 rc = -EIO;
1550                         common->next_buffhd_to_fill = bh->next;
1551                         if (common->fsg)
1552                                 rc = halt_bulk_in_endpoint(common->fsg);
1553                 } else if (fsg_is_set(common)) {
1554                         rc = pad_with_zeros(common->fsg);
1555                 } else {
1556                         /* Don't know what to do if common->fsg is NULL */
1557                         rc = -EIO;
1558                 }
1559                 break;
1560
1561         /* We have processed all we want from the data the host has sent.
1562          * There may still be outstanding bulk-out requests. */
1563         case DATA_DIR_FROM_HOST:
1564                 if (common->residue == 0) {
1565                         /* Nothing to receive */
1566
1567                 /* Did the host stop sending unexpectedly early? */
1568                 } else if (common->short_packet_received) {
1569                         raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1570                         rc = -EINTR;
1571
1572                 /* We haven't processed all the incoming data.  Even though
1573                  * we may be allowed to stall, doing so would cause a race.
1574                  * The controller may already have ACK'ed all the remaining
1575                  * bulk-out packets, in which case the host wouldn't see a
1576                  * STALL.  Not realizing the endpoint was halted, it wouldn't
1577                  * clear the halt -- leading to problems later on. */
1578 #if 0
1579                 } else if (common->can_stall) {
1580                         if (fsg_is_set(common))
1581                                 fsg_set_halt(common->fsg,
1582                                              common->fsg->bulk_out);
1583                         raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1584                         rc = -EINTR;
1585 #endif
1586
1587                 /* We can't stall.  Read in the excess data and throw it
1588                  * all away. */
1589                 } else {
1590                         rc = throw_away_data(common);
1591                 }
1592                 break;
1593         }
1594         return rc;
1595 }
1596
1597
1598 static int send_status(struct fsg_common *common)
1599 {
1600         struct fsg_lun          *curlun = &common->luns[common->lun];
1601         struct fsg_buffhd       *bh;
1602         struct bulk_cs_wrap     *csw;
1603         int                     rc;
1604         u8                      status = USB_STATUS_PASS;
1605         u32                     sd, sdinfo = 0;
1606
1607         /* Wait for the next buffer to become available */
1608         bh = common->next_buffhd_to_fill;
1609         while (bh->state != BUF_STATE_EMPTY) {
1610                 rc = sleep_thread(common);
1611                 if (rc)
1612                         return rc;
1613         }
1614
1615         if (curlun)
1616                 sd = curlun->sense_data;
1617         else if (common->bad_lun_okay)
1618                 sd = SS_NO_SENSE;
1619         else
1620                 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1621
1622         if (common->phase_error) {
1623                 DBG(common, "sending phase-error status\n");
1624                 status = USB_STATUS_PHASE_ERROR;
1625                 sd = SS_INVALID_COMMAND;
1626         } else if (sd != SS_NO_SENSE) {
1627                 DBG(common, "sending command-failure status\n");
1628                 status = USB_STATUS_FAIL;
1629                 VDBG(common, "  sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1630                         "  info x%x\n",
1631                         SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1632         }
1633
1634         /* Store and send the Bulk-only CSW */
1635         csw = (void *)bh->buf;
1636
1637         csw->Signature = cpu_to_le32(USB_BULK_CS_SIG);
1638         csw->Tag = common->tag;
1639         csw->Residue = cpu_to_le32(common->residue);
1640         csw->Status = status;
1641
1642         bh->inreq->length = USB_BULK_CS_WRAP_LEN;
1643         bh->inreq->zero = 0;
1644         START_TRANSFER_OR(common, bulk_in, bh->inreq,
1645                           &bh->inreq_busy, &bh->state)
1646                 /* Don't know what to do if common->fsg is NULL */
1647                 return -EIO;
1648
1649         common->next_buffhd_to_fill = bh->next;
1650         return 0;
1651 }
1652
1653
1654 /*-------------------------------------------------------------------------*/
1655
1656 /* Check whether the command is properly formed and whether its data size
1657  * and direction agree with the values we already have. */
1658 static int check_command(struct fsg_common *common, int cmnd_size,
1659                 enum data_direction data_dir, unsigned int mask,
1660                 int needs_medium, const char *name)
1661 {
1662         int                     i;
1663         int                     lun = common->cmnd[1] >> 5;
1664         static const char       dirletter[4] = {'u', 'o', 'i', 'n'};
1665         char                    hdlen[20];
1666         struct fsg_lun          *curlun;
1667
1668         hdlen[0] = 0;
1669         if (common->data_dir != DATA_DIR_UNKNOWN)
1670                 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1671                                 common->data_size);
1672         VDBG(common, "SCSI command: %s;  Dc=%d, D%c=%u;  Hc=%d%s\n",
1673              name, cmnd_size, dirletter[(int) data_dir],
1674              common->data_size_from_cmnd, common->cmnd_size, hdlen);
1675
1676         /* We can't reply at all until we know the correct data direction
1677          * and size. */
1678         if (common->data_size_from_cmnd == 0)
1679                 data_dir = DATA_DIR_NONE;
1680         if (common->data_size < common->data_size_from_cmnd) {
1681                 /* Host data size < Device data size is a phase error.
1682                  * Carry out the command, but only transfer as much as
1683                  * we are allowed. */
1684                 common->data_size_from_cmnd = common->data_size;
1685                 common->phase_error = 1;
1686         }
1687         common->residue = common->data_size;
1688         common->usb_amount_left = common->data_size;
1689
1690         /* Conflicting data directions is a phase error */
1691         if (common->data_dir != data_dir
1692          && common->data_size_from_cmnd > 0) {
1693                 common->phase_error = 1;
1694                 return -EINVAL;
1695         }
1696
1697         /* Verify the length of the command itself */
1698         if (cmnd_size != common->cmnd_size) {
1699
1700                 /* Special case workaround: There are plenty of buggy SCSI
1701                  * implementations. Many have issues with cbw->Length
1702                  * field passing a wrong command size. For those cases we
1703                  * always try to work around the problem by using the length
1704                  * sent by the host side provided it is at least as large
1705                  * as the correct command length.
1706                  * Examples of such cases would be MS-Windows, which issues
1707                  * REQUEST SENSE with cbw->Length == 12 where it should
1708                  * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1709                  * REQUEST SENSE with cbw->Length == 10 where it should
1710                  * be 6 as well.
1711                  */
1712                 if (cmnd_size <= common->cmnd_size) {
1713                         DBG(common, "%s is buggy! Expected length %d "
1714                             "but we got %d\n", name,
1715                             cmnd_size, common->cmnd_size);
1716                         cmnd_size = common->cmnd_size;
1717                 } else {
1718                         common->phase_error = 1;
1719                         return -EINVAL;
1720                 }
1721         }
1722
1723         /* Check that the LUN values are consistent */
1724         if (common->lun != lun)
1725                 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1726                     common->lun, lun);
1727
1728         /* Check the LUN */
1729         if (common->lun >= 0 && common->lun < common->nluns) {
1730                 curlun = &common->luns[common->lun];
1731                 if (common->cmnd[0] != SC_REQUEST_SENSE) {
1732                         curlun->sense_data = SS_NO_SENSE;
1733                         curlun->info_valid = 0;
1734                 }
1735         } else {
1736                 curlun = NULL;
1737                 common->bad_lun_okay = 0;
1738
1739                 /* INQUIRY and REQUEST SENSE commands are explicitly allowed
1740                  * to use unsupported LUNs; all others may not. */
1741                 if (common->cmnd[0] != SC_INQUIRY &&
1742                     common->cmnd[0] != SC_REQUEST_SENSE) {
1743                         DBG(common, "unsupported LUN %d\n", common->lun);
1744                         return -EINVAL;
1745                 }
1746         }
1747 #if 0
1748         /* If a unit attention condition exists, only INQUIRY and
1749          * REQUEST SENSE commands are allowed; anything else must fail. */
1750         if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1751                         common->cmnd[0] != SC_INQUIRY &&
1752                         common->cmnd[0] != SC_REQUEST_SENSE) {
1753                 curlun->sense_data = curlun->unit_attention_data;
1754                 curlun->unit_attention_data = SS_NO_SENSE;
1755                 return -EINVAL;
1756         }
1757 #endif
1758         /* Check that only command bytes listed in the mask are non-zero */
1759         common->cmnd[1] &= 0x1f;                        /* Mask away the LUN */
1760         for (i = 1; i < cmnd_size; ++i) {
1761                 if (common->cmnd[i] && !(mask & (1 << i))) {
1762                         if (curlun)
1763                                 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1764                         return -EINVAL;
1765                 }
1766         }
1767
1768         return 0;
1769 }
1770
1771
1772 static int do_scsi_command(struct fsg_common *common)
1773 {
1774         struct fsg_buffhd       *bh;
1775         int                     rc;
1776         int                     reply = -EINVAL;
1777         int                     i;
1778         static char             unknown[16];
1779         struct fsg_lun          *curlun = &common->luns[common->lun];
1780
1781         dump_cdb(common);
1782
1783         /* Wait for the next buffer to become available for data or status */
1784         bh = common->next_buffhd_to_fill;
1785         common->next_buffhd_to_drain = bh;
1786         while (bh->state != BUF_STATE_EMPTY) {
1787                 rc = sleep_thread(common);
1788                 if (rc)
1789                         return rc;
1790         }
1791         common->phase_error = 0;
1792         common->short_packet_received = 0;
1793
1794         down_read(&common->filesem);    /* We're using the backing file */
1795         switch (common->cmnd[0]) {
1796
1797         case SC_INQUIRY:
1798                 common->data_size_from_cmnd = common->cmnd[4];
1799                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1800                                       (1<<4), 0,
1801                                       "INQUIRY");
1802                 if (reply == 0)
1803                         reply = do_inquiry(common, bh);
1804                 break;
1805
1806         case SC_MODE_SELECT_6:
1807                 common->data_size_from_cmnd = common->cmnd[4];
1808                 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1809                                       (1<<1) | (1<<4), 0,
1810                                       "MODE SELECT(6)");
1811                 if (reply == 0)
1812                         reply = do_mode_select(common, bh);
1813                 break;
1814
1815         case SC_MODE_SELECT_10:
1816                 common->data_size_from_cmnd =
1817                         get_unaligned_be16(&common->cmnd[7]);
1818                 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1819                                       (1<<1) | (3<<7), 0,
1820                                       "MODE SELECT(10)");
1821                 if (reply == 0)
1822                         reply = do_mode_select(common, bh);
1823                 break;
1824
1825         case SC_MODE_SENSE_6:
1826                 common->data_size_from_cmnd = common->cmnd[4];
1827                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1828                                       (1<<1) | (1<<2) | (1<<4), 0,
1829                                       "MODE SENSE(6)");
1830                 if (reply == 0)
1831                         reply = do_mode_sense(common, bh);
1832                 break;
1833
1834         case SC_MODE_SENSE_10:
1835                 common->data_size_from_cmnd =
1836                         get_unaligned_be16(&common->cmnd[7]);
1837                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1838                                       (1<<1) | (1<<2) | (3<<7), 0,
1839                                       "MODE SENSE(10)");
1840                 if (reply == 0)
1841                         reply = do_mode_sense(common, bh);
1842                 break;
1843
1844         case SC_PREVENT_ALLOW_MEDIUM_REMOVAL:
1845                 common->data_size_from_cmnd = 0;
1846                 reply = check_command(common, 6, DATA_DIR_NONE,
1847                                       (1<<4), 0,
1848                                       "PREVENT-ALLOW MEDIUM REMOVAL");
1849                 if (reply == 0)
1850                         reply = do_prevent_allow(common);
1851                 break;
1852
1853         case SC_READ_6:
1854                 i = common->cmnd[4];
1855                 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1856                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1857                                       (7<<1) | (1<<4), 1,
1858                                       "READ(6)");
1859                 if (reply == 0)
1860                         reply = do_read(common);
1861                 break;
1862
1863         case SC_READ_10:
1864                 common->data_size_from_cmnd =
1865                                 get_unaligned_be16(&common->cmnd[7]) << 9;
1866                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1867                                       (1<<1) | (0xf<<2) | (3<<7), 1,
1868                                       "READ(10)");
1869                 if (reply == 0)
1870                         reply = do_read(common);
1871                 break;
1872
1873         case SC_READ_12:
1874                 common->data_size_from_cmnd =
1875                                 get_unaligned_be32(&common->cmnd[6]) << 9;
1876                 reply = check_command(common, 12, DATA_DIR_TO_HOST,
1877                                       (1<<1) | (0xf<<2) | (0xf<<6), 1,
1878                                       "READ(12)");
1879                 if (reply == 0)
1880                         reply = do_read(common);
1881                 break;
1882
1883         case SC_READ_CAPACITY:
1884                 common->data_size_from_cmnd = 8;
1885                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1886                                       (0xf<<2) | (1<<8), 1,
1887                                       "READ CAPACITY");
1888                 if (reply == 0)
1889                         reply = do_read_capacity(common, bh);
1890                 break;
1891
1892         case SC_READ_HEADER:
1893                 if (!common->luns[common->lun].cdrom)
1894                         goto unknown_cmnd;
1895                 common->data_size_from_cmnd =
1896                         get_unaligned_be16(&common->cmnd[7]);
1897                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1898                                       (3<<7) | (0x1f<<1), 1,
1899                                       "READ HEADER");
1900                 if (reply == 0)
1901                         reply = do_read_header(common, bh);
1902                 break;
1903
1904         case SC_READ_TOC:
1905                 if (!common->luns[common->lun].cdrom)
1906                         goto unknown_cmnd;
1907                 common->data_size_from_cmnd =
1908                         get_unaligned_be16(&common->cmnd[7]);
1909                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1910                                       (7<<6) | (1<<1), 1,
1911                                       "READ TOC");
1912                 if (reply == 0)
1913                         reply = do_read_toc(common, bh);
1914                 break;
1915
1916         case SC_READ_FORMAT_CAPACITIES:
1917                 common->data_size_from_cmnd =
1918                         get_unaligned_be16(&common->cmnd[7]);
1919                 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1920                                       (3<<7), 1,
1921                                       "READ FORMAT CAPACITIES");
1922                 if (reply == 0)
1923                         reply = do_read_format_capacities(common, bh);
1924                 break;
1925
1926         case SC_REQUEST_SENSE:
1927                 common->data_size_from_cmnd = common->cmnd[4];
1928                 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1929                                       (1<<4), 0,
1930                                       "REQUEST SENSE");
1931                 if (reply == 0)
1932                         reply = do_request_sense(common, bh);
1933                 break;
1934
1935         case SC_START_STOP_UNIT:
1936                 common->data_size_from_cmnd = 0;
1937                 reply = check_command(common, 6, DATA_DIR_NONE,
1938                                       (1<<1) | (1<<4), 0,
1939                                       "START-STOP UNIT");
1940                 if (reply == 0)
1941                         reply = do_start_stop(common);
1942                 break;
1943
1944         case SC_SYNCHRONIZE_CACHE:
1945                 common->data_size_from_cmnd = 0;
1946                 reply = check_command(common, 10, DATA_DIR_NONE,
1947                                       (0xf<<2) | (3<<7), 1,
1948                                       "SYNCHRONIZE CACHE");
1949                 if (reply == 0)
1950                         reply = do_synchronize_cache(common);
1951                 break;
1952
1953         case SC_TEST_UNIT_READY:
1954                 common->data_size_from_cmnd = 0;
1955                 reply = check_command(common, 6, DATA_DIR_NONE,
1956                                 0, 1,
1957                                 "TEST UNIT READY");
1958                 break;
1959
1960         /* Although optional, this command is used by MS-Windows.  We
1961          * support a minimal version: BytChk must be 0. */
1962         case SC_VERIFY:
1963                 common->data_size_from_cmnd = 0;
1964                 reply = check_command(common, 10, DATA_DIR_NONE,
1965                                       (1<<1) | (0xf<<2) | (3<<7), 1,
1966                                       "VERIFY");
1967                 if (reply == 0)
1968                         reply = do_verify(common);
1969                 break;
1970
1971         case SC_WRITE_6:
1972                 i = common->cmnd[4];
1973                 common->data_size_from_cmnd = (i == 0 ? 256 : i) << 9;
1974                 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1975                                       (7<<1) | (1<<4), 1,
1976                                       "WRITE(6)");
1977                 if (reply == 0)
1978                         reply = do_write(common);
1979                 break;
1980
1981         case SC_WRITE_10:
1982                 common->data_size_from_cmnd =
1983                                 get_unaligned_be16(&common->cmnd[7]) << 9;
1984                 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1985                                       (1<<1) | (0xf<<2) | (3<<7), 1,
1986                                       "WRITE(10)");
1987                 if (reply == 0)
1988                         reply = do_write(common);
1989                 break;
1990
1991         case SC_WRITE_12:
1992                 common->data_size_from_cmnd =
1993                                 get_unaligned_be32(&common->cmnd[6]) << 9;
1994                 reply = check_command(common, 12, DATA_DIR_FROM_HOST,
1995                                       (1<<1) | (0xf<<2) | (0xf<<6), 1,
1996                                       "WRITE(12)");
1997                 if (reply == 0)
1998                         reply = do_write(common);
1999                 break;
2000
2001         /* Some mandatory commands that we recognize but don't implement.
2002          * They don't mean much in this setting.  It's left as an exercise
2003          * for anyone interested to implement RESERVE and RELEASE in terms
2004          * of Posix locks. */
2005         case SC_FORMAT_UNIT:
2006         case SC_RELEASE:
2007         case SC_RESERVE:
2008         case SC_SEND_DIAGNOSTIC:
2009                 /* Fall through */
2010
2011         default:
2012 unknown_cmnd:
2013                 common->data_size_from_cmnd = 0;
2014                 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2015                 reply = check_command(common, common->cmnd_size,
2016                                       DATA_DIR_UNKNOWN, 0xff, 0, unknown);
2017                 if (reply == 0) {
2018                         curlun->sense_data = SS_INVALID_COMMAND;
2019                         reply = -EINVAL;
2020                 }
2021                 break;
2022         }
2023         up_read(&common->filesem);
2024
2025         if (reply == -EINTR)
2026                 return -EINTR;
2027
2028         /* Set up the single reply buffer for finish_reply() */
2029         if (reply == -EINVAL)
2030                 reply = 0;              /* Error reply length */
2031         if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2032                 reply = min((u32) reply, common->data_size_from_cmnd);
2033                 bh->inreq->length = reply;
2034                 bh->state = BUF_STATE_FULL;
2035                 common->residue -= reply;
2036         }                               /* Otherwise it's already set */
2037
2038         return 0;
2039 }
2040
2041 /*-------------------------------------------------------------------------*/
2042
2043 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2044 {
2045         struct usb_request      *req = bh->outreq;
2046         struct fsg_bulk_cb_wrap *cbw = req->buf;
2047         struct fsg_common       *common = fsg->common;
2048
2049         /* Was this a real packet?  Should it be ignored? */
2050         if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2051                 return -EINVAL;
2052
2053         /* Is the CBW valid? */
2054         if (req->actual != USB_BULK_CB_WRAP_LEN ||
2055                         cbw->Signature != cpu_to_le32(
2056                                 USB_BULK_CB_SIG)) {
2057                 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2058                                 req->actual,
2059                                 le32_to_cpu(cbw->Signature));
2060
2061                 /* The Bulk-only spec says we MUST stall the IN endpoint
2062                  * (6.6.1), so it's unavoidable.  It also says we must
2063                  * retain this state until the next reset, but there's
2064                  * no way to tell the controller driver it should ignore
2065                  * Clear-Feature(HALT) requests.
2066                  *
2067                  * We aren't required to halt the OUT endpoint; instead
2068                  * we can simply accept and discard any data received
2069                  * until the next reset. */
2070                 wedge_bulk_in_endpoint(fsg);
2071                 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2072                 return -EINVAL;
2073         }
2074
2075         /* Is the CBW meaningful? */
2076         if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~USB_BULK_IN_FLAG ||
2077                         cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2078                 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2079                                 "cmdlen %u\n",
2080                                 cbw->Lun, cbw->Flags, cbw->Length);
2081
2082                 /* We can do anything we want here, so let's stall the
2083                  * bulk pipes if we are allowed to. */
2084                 if (common->can_stall) {
2085                         fsg_set_halt(fsg, fsg->bulk_out);
2086                         halt_bulk_in_endpoint(fsg);
2087                 }
2088                 return -EINVAL;
2089         }
2090
2091         /* Save the command for later */
2092         common->cmnd_size = cbw->Length;
2093         memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2094         if (cbw->Flags & USB_BULK_IN_FLAG)
2095                 common->data_dir = DATA_DIR_TO_HOST;
2096         else
2097                 common->data_dir = DATA_DIR_FROM_HOST;
2098         common->data_size = le32_to_cpu(cbw->DataTransferLength);
2099         if (common->data_size == 0)
2100                 common->data_dir = DATA_DIR_NONE;
2101         common->lun = cbw->Lun;
2102         common->tag = cbw->Tag;
2103         return 0;
2104 }
2105
2106
2107 static int get_next_command(struct fsg_common *common)
2108 {
2109         struct fsg_buffhd       *bh;
2110         int                     rc = 0;
2111
2112         /* Wait for the next buffer to become available */
2113         bh = common->next_buffhd_to_fill;
2114         while (bh->state != BUF_STATE_EMPTY) {
2115                 rc = sleep_thread(common);
2116                 if (rc)
2117                         return rc;
2118         }
2119
2120         /* Queue a request to read a Bulk-only CBW */
2121         set_bulk_out_req_length(common, bh, USB_BULK_CB_WRAP_LEN);
2122         bh->outreq->short_not_ok = 1;
2123         START_TRANSFER_OR(common, bulk_out, bh->outreq,
2124                           &bh->outreq_busy, &bh->state)
2125                 /* Don't know what to do if common->fsg is NULL */
2126                 return -EIO;
2127
2128         /* We will drain the buffer in software, which means we
2129          * can reuse it for the next filling.  No need to advance
2130          * next_buffhd_to_fill. */
2131
2132         /* Wait for the CBW to arrive */
2133         while (bh->state != BUF_STATE_FULL) {
2134                 rc = sleep_thread(common);
2135                 if (rc)
2136                         return rc;
2137         }
2138
2139         rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2140         bh->state = BUF_STATE_EMPTY;
2141
2142         return rc;
2143 }
2144
2145
2146 /*-------------------------------------------------------------------------*/
2147
2148 static int enable_endpoint(struct fsg_common *common, struct usb_ep *ep,
2149                 const struct usb_endpoint_descriptor *d)
2150 {
2151         int     rc;
2152
2153         ep->driver_data = common;
2154         rc = usb_ep_enable(ep, d);
2155         if (rc)
2156                 ERROR(common, "can't enable %s, result %d\n", ep->name, rc);
2157         return rc;
2158 }
2159
2160 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2161                 struct usb_request **preq)
2162 {
2163         *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2164         if (*preq)
2165                 return 0;
2166         ERROR(common, "can't allocate request for %s\n", ep->name);
2167         return -ENOMEM;
2168 }
2169
2170 /* Reset interface setting and re-init endpoint state (toggle etc). */
2171 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2172 {
2173         const struct usb_endpoint_descriptor *d;
2174         struct fsg_dev *fsg;
2175         int i, rc = 0;
2176
2177         if (common->running)
2178                 DBG(common, "reset interface\n");
2179
2180 reset:
2181         /* Deallocate the requests */
2182         if (common->fsg) {
2183                 fsg = common->fsg;
2184
2185                 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2186                         struct fsg_buffhd *bh = &common->buffhds[i];
2187
2188                         if (bh->inreq) {
2189                                 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2190                                 bh->inreq = NULL;
2191                         }
2192                         if (bh->outreq) {
2193                                 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2194                                 bh->outreq = NULL;
2195                         }
2196                 }
2197
2198                 /* Disable the endpoints */
2199                 if (fsg->bulk_in_enabled) {
2200                         usb_ep_disable(fsg->bulk_in);
2201                         fsg->bulk_in_enabled = 0;
2202                 }
2203                 if (fsg->bulk_out_enabled) {
2204                         usb_ep_disable(fsg->bulk_out);
2205                         fsg->bulk_out_enabled = 0;
2206                 }
2207
2208                 common->fsg = NULL;
2209                 /* wake_up(&common->fsg_wait); */
2210         }
2211
2212         common->running = 0;
2213         if (!new_fsg || rc)
2214                 return rc;
2215
2216         common->fsg = new_fsg;
2217         fsg = common->fsg;
2218
2219         /* Enable the endpoints */
2220         d = fsg_ep_desc(common->gadget,
2221                         &fsg_fs_bulk_in_desc, &fsg_hs_bulk_in_desc);
2222         rc = enable_endpoint(common, fsg->bulk_in, d);
2223         if (rc)
2224                 goto reset;
2225         fsg->bulk_in_enabled = 1;
2226
2227         d = fsg_ep_desc(common->gadget,
2228                         &fsg_fs_bulk_out_desc, &fsg_hs_bulk_out_desc);
2229         rc = enable_endpoint(common, fsg->bulk_out, d);
2230         if (rc)
2231                 goto reset;
2232         fsg->bulk_out_enabled = 1;
2233         common->bulk_out_maxpacket =
2234                                 le16_to_cpu(get_unaligned(&d->wMaxPacketSize));
2235         clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2236
2237         /* Allocate the requests */
2238         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2239                 struct fsg_buffhd       *bh = &common->buffhds[i];
2240
2241                 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2242                 if (rc)
2243                         goto reset;
2244                 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2245                 if (rc)
2246                         goto reset;
2247                 bh->inreq->buf = bh->outreq->buf = bh->buf;
2248                 bh->inreq->context = bh->outreq->context = bh;
2249                 bh->inreq->complete = bulk_in_complete;
2250                 bh->outreq->complete = bulk_out_complete;
2251         }
2252
2253         common->running = 1;
2254
2255         return rc;
2256 }
2257
2258
2259 /****************************** ALT CONFIGS ******************************/
2260
2261
2262 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2263 {
2264         struct fsg_dev *fsg = fsg_from_func(f);
2265         fsg->common->new_fsg = fsg;
2266         raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2267         return 0;
2268 }
2269
2270 static void fsg_disable(struct usb_function *f)
2271 {
2272         struct fsg_dev *fsg = fsg_from_func(f);
2273         fsg->common->new_fsg = NULL;
2274         raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2275 }
2276
2277 /*-------------------------------------------------------------------------*/
2278
2279 static void handle_exception(struct fsg_common *common)
2280 {
2281         int                     i;
2282         struct fsg_buffhd       *bh;
2283         enum fsg_state          old_state;
2284         struct fsg_lun          *curlun;
2285         unsigned int            exception_req_tag;
2286
2287         /* Cancel all the pending transfers */
2288         if (common->fsg) {
2289                 for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2290                         bh = &common->buffhds[i];
2291                         if (bh->inreq_busy)
2292                                 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2293                         if (bh->outreq_busy)
2294                                 usb_ep_dequeue(common->fsg->bulk_out,
2295                                                bh->outreq);
2296                 }
2297
2298                 /* Wait until everything is idle */
2299                 for (;;) {
2300                         int num_active = 0;
2301                         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2302                                 bh = &common->buffhds[i];
2303                                 num_active += bh->inreq_busy + bh->outreq_busy;
2304                         }
2305                         if (num_active == 0)
2306                                 break;
2307                         if (sleep_thread(common))
2308                                 return;
2309                 }
2310
2311                 /* Clear out the controller's fifos */
2312                 if (common->fsg->bulk_in_enabled)
2313                         usb_ep_fifo_flush(common->fsg->bulk_in);
2314                 if (common->fsg->bulk_out_enabled)
2315                         usb_ep_fifo_flush(common->fsg->bulk_out);
2316         }
2317
2318         /* Reset the I/O buffer states and pointers, the SCSI
2319          * state, and the exception.  Then invoke the handler. */
2320
2321         for (i = 0; i < FSG_NUM_BUFFERS; ++i) {
2322                 bh = &common->buffhds[i];
2323                 bh->state = BUF_STATE_EMPTY;
2324         }
2325         common->next_buffhd_to_fill = &common->buffhds[0];
2326         common->next_buffhd_to_drain = &common->buffhds[0];
2327         exception_req_tag = common->exception_req_tag;
2328         old_state = common->state;
2329
2330         if (old_state == FSG_STATE_ABORT_BULK_OUT)
2331                 common->state = FSG_STATE_STATUS_PHASE;
2332         else {
2333                 for (i = 0; i < common->nluns; ++i) {
2334                         curlun = &common->luns[i];
2335                         curlun->sense_data = SS_NO_SENSE;
2336                         curlun->info_valid = 0;
2337                 }
2338                 common->state = FSG_STATE_IDLE;
2339         }
2340
2341         /* Carry out any extra actions required for the exception */
2342         switch (old_state) {
2343         case FSG_STATE_ABORT_BULK_OUT:
2344                 send_status(common);
2345
2346                 if (common->state == FSG_STATE_STATUS_PHASE)
2347                         common->state = FSG_STATE_IDLE;
2348                 break;
2349
2350         case FSG_STATE_RESET:
2351                 /* In case we were forced against our will to halt a
2352                  * bulk endpoint, clear the halt now.  (The SuperH UDC
2353                  * requires this.) */
2354                 if (!fsg_is_set(common))
2355                         break;
2356                 if (test_and_clear_bit(IGNORE_BULK_OUT,
2357                                        &common->fsg->atomic_bitflags))
2358                         usb_ep_clear_halt(common->fsg->bulk_in);
2359
2360                 if (common->ep0_req_tag == exception_req_tag)
2361                         ep0_queue(common);      /* Complete the status stage */
2362
2363                 break;
2364
2365         case FSG_STATE_CONFIG_CHANGE:
2366                 do_set_interface(common, common->new_fsg);
2367                 break;
2368
2369         case FSG_STATE_EXIT:
2370         case FSG_STATE_TERMINATED:
2371                 do_set_interface(common, NULL);         /* Free resources */
2372                 common->state = FSG_STATE_TERMINATED;   /* Stop the thread */
2373                 break;
2374
2375         case FSG_STATE_INTERFACE_CHANGE:
2376         case FSG_STATE_DISCONNECT:
2377         case FSG_STATE_COMMAND_PHASE:
2378         case FSG_STATE_DATA_PHASE:
2379         case FSG_STATE_STATUS_PHASE:
2380         case FSG_STATE_IDLE:
2381                 break;
2382         }
2383 }
2384
2385 /*-------------------------------------------------------------------------*/
2386
2387 int fsg_main_thread(void *common_)
2388 {
2389         struct fsg_common       *common = the_fsg_common;
2390         /* The main loop */
2391         do {
2392                 if (exception_in_progress(common)) {
2393                         handle_exception(common);
2394                         continue;
2395                 }
2396
2397                 if (!common->running) {
2398                         sleep_thread(common);
2399                         continue;
2400                 }
2401
2402                 if (get_next_command(common))
2403                         continue;
2404
2405                 if (!exception_in_progress(common))
2406                         common->state = FSG_STATE_DATA_PHASE;
2407
2408                 if (do_scsi_command(common) || finish_reply(common))
2409                         continue;
2410
2411                 if (!exception_in_progress(common))
2412                         common->state = FSG_STATE_STATUS_PHASE;
2413
2414                 if (send_status(common))
2415                         continue;
2416
2417                 if (!exception_in_progress(common))
2418                         common->state = FSG_STATE_IDLE;
2419         } while (0);
2420
2421         common->thread_task = NULL;
2422
2423         return 0;
2424 }
2425
2426 static void fsg_common_release(struct kref *ref);
2427
2428 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2429                                           struct usb_composite_dev *cdev)
2430 {
2431         struct usb_gadget *gadget = cdev->gadget;
2432         struct fsg_buffhd *bh;
2433         struct fsg_lun *curlun;
2434         int nluns, i, rc;
2435
2436         /* Find out how many LUNs there should be */
2437         nluns = 1;
2438         if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2439                 printf("invalid number of LUNs: %u\n", nluns);
2440                 return ERR_PTR(-EINVAL);
2441         }
2442
2443         /* Allocate? */
2444         if (!common) {
2445                 common = calloc(sizeof *common, 1);
2446                 if (!common)
2447                         return ERR_PTR(-ENOMEM);
2448                 common->free_storage_on_release = 1;
2449         } else {
2450                 memset(common, 0, sizeof common);
2451                 common->free_storage_on_release = 0;
2452         }
2453
2454         common->ops = NULL;
2455         common->private_data = NULL;
2456
2457         common->gadget = gadget;
2458         common->ep0 = gadget->ep0;
2459         common->ep0req = cdev->req;
2460
2461         /* Maybe allocate device-global string IDs, and patch descriptors */
2462         if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2463                 rc = usb_string_id(cdev);
2464                 if (unlikely(rc < 0))
2465                         goto error_release;
2466                 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2467                 fsg_intf_desc.iInterface = rc;
2468         }
2469
2470         /* Create the LUNs, open their backing files, and register the
2471          * LUN devices in sysfs. */
2472         curlun = calloc(nluns, sizeof *curlun);
2473         if (!curlun) {
2474                 rc = -ENOMEM;
2475                 goto error_release;
2476         }
2477         common->nluns = nluns;
2478
2479         for (i = 0; i < nluns; i++) {
2480                 common->luns[i].removable = 1;
2481
2482                 rc = fsg_lun_open(&common->luns[i], "");
2483                 if (rc)
2484                         goto error_luns;
2485         }
2486         common->lun = 0;
2487
2488         /* Data buffers cyclic list */
2489         bh = common->buffhds;
2490
2491         i = FSG_NUM_BUFFERS;
2492         goto buffhds_first_it;
2493         do {
2494                 bh->next = bh + 1;
2495                 ++bh;
2496 buffhds_first_it:
2497                 bh->inreq_busy = 0;
2498                 bh->outreq_busy = 0;
2499                 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2500                 if (unlikely(!bh->buf)) {
2501                         rc = -ENOMEM;
2502                         goto error_release;
2503                 }
2504         } while (--i);
2505         bh->next = common->buffhds;
2506
2507         snprintf(common->inquiry_string, sizeof common->inquiry_string,
2508                  "%-8s%-16s%04x",
2509                  "Linux   ",
2510                  "File-Store Gadget",
2511                  0xffff);
2512
2513         /* Some peripheral controllers are known not to be able to
2514          * halt bulk endpoints correctly.  If one of them is present,
2515          * disable stalls.
2516          */
2517
2518         /* Tell the thread to start working */
2519         common->thread_task =
2520                 kthread_create(fsg_main_thread, common,
2521                                OR(cfg->thread_name, "file-storage"));
2522         if (IS_ERR(common->thread_task)) {
2523                 rc = PTR_ERR(common->thread_task);
2524                 goto error_release;
2525         }
2526
2527 #undef OR
2528         /* Information */
2529         INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2530         INFO(common, "Number of LUNs=%d\n", common->nluns);
2531
2532         return common;
2533
2534 error_luns:
2535         common->nluns = i + 1;
2536 error_release:
2537         common->state = FSG_STATE_TERMINATED;   /* The thread is dead */
2538         /* Call fsg_common_release() directly, ref might be not
2539          * initialised */
2540         fsg_common_release(&common->ref);
2541         return ERR_PTR(rc);
2542 }
2543
2544 static void fsg_common_release(struct kref *ref)
2545 {
2546         struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2547
2548         /* If the thread isn't already dead, tell it to exit now */
2549         if (common->state != FSG_STATE_TERMINATED) {
2550                 raise_exception(common, FSG_STATE_EXIT);
2551                 wait_for_completion(&common->thread_notifier);
2552         }
2553
2554         if (likely(common->luns)) {
2555                 struct fsg_lun *lun = common->luns;
2556                 unsigned i = common->nluns;
2557
2558                 /* In error recovery common->nluns may be zero. */
2559                 for (; i; --i, ++lun)
2560                         fsg_lun_close(lun);
2561
2562                 kfree(common->luns);
2563         }
2564
2565         {
2566                 struct fsg_buffhd *bh = common->buffhds;
2567                 unsigned i = FSG_NUM_BUFFERS;
2568                 do {
2569                         kfree(bh->buf);
2570                 } while (++bh, --i);
2571         }
2572
2573         if (common->free_storage_on_release)
2574                 kfree(common);
2575 }
2576
2577
2578 /*-------------------------------------------------------------------------*/
2579
2580 /**
2581  * usb_copy_descriptors - copy a vector of USB descriptors
2582  * @src: null-terminated vector to copy
2583  * Context: initialization code, which may sleep
2584  *
2585  * This makes a copy of a vector of USB descriptors.  Its primary use
2586  * is to support usb_function objects which can have multiple copies,
2587  * each needing different descriptors.  Functions may have static
2588  * tables of descriptors, which are used as templates and customized
2589  * with identifiers (for interfaces, strings, endpoints, and more)
2590  * as needed by a given function instance.
2591  */
2592 struct usb_descriptor_header **
2593 usb_copy_descriptors(struct usb_descriptor_header **src)
2594 {
2595         struct usb_descriptor_header **tmp;
2596         unsigned bytes;
2597         unsigned n_desc;
2598         void *mem;
2599         struct usb_descriptor_header **ret;
2600
2601         /* count descriptors and their sizes; then add vector size */
2602         for (bytes = 0, n_desc = 0, tmp = src; *tmp; tmp++, n_desc++)
2603                 bytes += (*tmp)->bLength;
2604         bytes += (n_desc + 1) * sizeof(*tmp);
2605
2606         mem = kmalloc(bytes, GFP_KERNEL);
2607         if (!mem)
2608                 return NULL;
2609
2610         /* fill in pointers starting at "tmp",
2611          * to descriptors copied starting at "mem";
2612          * and return "ret"
2613          */
2614         tmp = mem;
2615         ret = mem;
2616         mem += (n_desc + 1) * sizeof(*tmp);
2617         while (*src) {
2618                 memcpy(mem, *src, (*src)->bLength);
2619                 *tmp = mem;
2620                 tmp++;
2621                 mem += (*src)->bLength;
2622                 src++;
2623         }
2624         *tmp = NULL;
2625
2626         return ret;
2627 }
2628
2629 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2630 {
2631         struct fsg_dev          *fsg = fsg_from_func(f);
2632
2633         DBG(fsg, "unbind\n");
2634         if (fsg->common->fsg == fsg) {
2635                 fsg->common->new_fsg = NULL;
2636                 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2637         }
2638
2639         free(fsg->function.descriptors);
2640         free(fsg->function.hs_descriptors);
2641         kfree(fsg);
2642 }
2643
2644 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2645 {
2646         struct fsg_dev          *fsg = fsg_from_func(f);
2647         struct usb_gadget       *gadget = c->cdev->gadget;
2648         int                     i;
2649         struct usb_ep           *ep;
2650         fsg->gadget = gadget;
2651
2652         /* New interface */
2653         i = usb_interface_id(c, f);
2654         if (i < 0)
2655                 return i;
2656         fsg_intf_desc.bInterfaceNumber = i;
2657         fsg->interface_number = i;
2658
2659         /* Find all the endpoints we will use */
2660         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2661         if (!ep)
2662                 goto autoconf_fail;
2663         ep->driver_data = fsg->common;  /* claim the endpoint */
2664         fsg->bulk_in = ep;
2665
2666         ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2667         if (!ep)
2668                 goto autoconf_fail;
2669         ep->driver_data = fsg->common;  /* claim the endpoint */
2670         fsg->bulk_out = ep;
2671
2672         /* Copy descriptors */
2673         f->descriptors = usb_copy_descriptors(fsg_fs_function);
2674         if (unlikely(!f->descriptors))
2675                 return -ENOMEM;
2676
2677         if (gadget_is_dualspeed(gadget)) {
2678                 /* Assume endpoint addresses are the same for both speeds */
2679                 fsg_hs_bulk_in_desc.bEndpointAddress =
2680                         fsg_fs_bulk_in_desc.bEndpointAddress;
2681                 fsg_hs_bulk_out_desc.bEndpointAddress =
2682                         fsg_fs_bulk_out_desc.bEndpointAddress;
2683                 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
2684                 if (unlikely(!f->hs_descriptors)) {
2685                         free(f->descriptors);
2686                         return -ENOMEM;
2687                 }
2688         }
2689         return 0;
2690
2691 autoconf_fail:
2692         ERROR(fsg, "unable to autoconfigure all endpoints\n");
2693         return -ENOTSUPP;
2694 }
2695
2696
2697 /****************************** ADD FUNCTION ******************************/
2698
2699 static struct usb_gadget_strings *fsg_strings_array[] = {
2700         &fsg_stringtab,
2701         NULL,
2702 };
2703
2704 static int fsg_bind_config(struct usb_composite_dev *cdev,
2705                            struct usb_configuration *c,
2706                            struct fsg_common *common)
2707 {
2708         struct fsg_dev *fsg;
2709         int rc;
2710
2711         fsg = calloc(1, sizeof *fsg);
2712         if (!fsg)
2713                 return -ENOMEM;
2714         fsg->function.name        = FSG_DRIVER_DESC;
2715         fsg->function.strings     = fsg_strings_array;
2716         fsg->function.bind        = fsg_bind;
2717         fsg->function.unbind      = fsg_unbind;
2718         fsg->function.setup       = fsg_setup;
2719         fsg->function.set_alt     = fsg_set_alt;
2720         fsg->function.disable     = fsg_disable;
2721
2722         fsg->common               = common;
2723         common->fsg               = fsg;
2724         /* Our caller holds a reference to common structure so we
2725          * don't have to be worry about it being freed until we return
2726          * from this function.  So instead of incrementing counter now
2727          * and decrement in error recovery we increment it only when
2728          * call to usb_add_function() was successful. */
2729
2730         rc = usb_add_function(c, &fsg->function);
2731
2732         if (rc)
2733                 kfree(fsg);
2734
2735         return rc;
2736 }
2737
2738 int fsg_add(struct usb_configuration *c)
2739 {
2740         struct fsg_common *fsg_common;
2741
2742         fsg_common = fsg_common_init(NULL, c->cdev);
2743
2744         fsg_common->vendor_name = 0;
2745         fsg_common->product_name = 0;
2746         fsg_common->release = 0xffff;
2747
2748         fsg_common->ops = NULL;
2749         fsg_common->private_data = NULL;
2750
2751         the_fsg_common = fsg_common;
2752
2753         return fsg_bind_config(c->cdev, c, fsg_common);
2754 }
2755
2756 int fsg_init(struct ums_board_info *ums)
2757 {
2758         ums_info = ums;
2759
2760         return 0;
2761 }