2 * f_mass_storage.c -- Mass Storage USB Composite Function
4 * Copyright (C) 2003-2008 Alan Stern
5 * Copyright (C) 2009 Samsung Electronics
6 * Author: Michal Nazarewicz <mina86@mina86.com>
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer,
14 * without modification.
15 * 2. Redistributions in binary form must reproduce the above copyright
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18 * 3. The names of the above-listed copyright holders may not be used
19 * to endorse or promote products derived from this software without
20 * specific prior written permission.
22 * ALTERNATIVELY, this software may be distributed under the terms of the
23 * GNU General Public License ("GPL") as published by the Free Software
24 * Foundation, either version 2 of that License or (at your option) any
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
28 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
29 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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35 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
36 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
37 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
41 * The Mass Storage Function acts as a USB Mass Storage device,
42 * appearing to the host as a disk drive or as a CD-ROM drive. In
43 * addition to providing an example of a genuinely useful composite
44 * function for a USB device, it also illustrates a technique of
45 * double-buffering for increased throughput.
47 * For more information about MSF and in particular its module
48 * parameters and sysfs interface read the
49 * <Documentation/usb/mass-storage.txt> file.
53 * MSF is configured by specifying a fsg_config structure. It has the
56 * nluns Number of LUNs function have (anywhere from 1
57 * to FSG_MAX_LUNS which is 8).
58 * luns An array of LUN configuration values. This
59 * should be filled for each LUN that
60 * function will include (ie. for "nluns"
61 * LUNs). Each element of the array has
62 * the following fields:
63 * ->filename The path to the backing file for the LUN.
64 * Required if LUN is not marked as
66 * ->ro Flag specifying access to the LUN shall be
67 * read-only. This is implied if CD-ROM
68 * emulation is enabled as well as when
69 * it was impossible to open "filename"
71 * ->removable Flag specifying that LUN shall be indicated as
73 * ->cdrom Flag specifying that LUN shall be reported as
75 * ->nofua Flag specifying that FUA flag in SCSI WRITE(10,12)
76 * commands for this LUN shall be ignored.
80 * release Information used as a reply to INQUIRY
81 * request. To use default set to NULL,
82 * NULL, 0xffff respectively. The first
83 * field should be 8 and the second 16
86 * can_stall Set to permit function to halt bulk endpoints.
87 * Disabled on some USB devices known not
88 * to work correctly. You should set it
91 * If "removable" is not set for a LUN then a backing file must be
92 * specified. If it is set, then NULL filename means the LUN's medium
93 * is not loaded (an empty string as "filename" in the fsg_config
94 * structure causes error). The CD-ROM emulation includes a single
95 * data track and no audio tracks; hence there need be only one
96 * backing file per LUN.
98 * This function is heavily based on "File-backed Storage Gadget" by
99 * Alan Stern which in turn is heavily based on "Gadget Zero" by David
100 * Brownell. The driver's SCSI command interface was based on the
101 * "Information technology - Small Computer System Interface - 2"
102 * document from X3T9.2 Project 375D, Revision 10L, 7-SEP-93,
103 * available at <http://www.t10.org/ftp/t10/drafts/s2/s2-r10l.pdf>.
104 * The single exception is opcode 0x23 (READ FORMAT CAPACITIES), which
105 * was based on the "Universal Serial Bus Mass Storage Class UFI
106 * Command Specification" document, Revision 1.0, December 14, 1998,
108 * <http://www.usb.org/developers/devclass_docs/usbmass-ufi10.pdf>.
114 * The MSF is fairly straightforward. There is a main kernel
115 * thread that handles most of the work. Interrupt routines field
116 * callbacks from the controller driver: bulk- and interrupt-request
117 * completion notifications, endpoint-0 events, and disconnect events.
118 * Completion events are passed to the main thread by wakeup calls. Many
119 * ep0 requests are handled at interrupt time, but SetInterface,
120 * SetConfiguration, and device reset requests are forwarded to the
121 * thread in the form of "exceptions" using SIGUSR1 signals (since they
122 * should interrupt any ongoing file I/O operations).
124 * The thread's main routine implements the standard command/data/status
125 * parts of a SCSI interaction. It and its subroutines are full of tests
126 * for pending signals/exceptions -- all this polling is necessary since
127 * the kernel has no setjmp/longjmp equivalents. (Maybe this is an
128 * indication that the driver really wants to be running in userspace.)
129 * An important point is that so long as the thread is alive it keeps an
130 * open reference to the backing file. This will prevent unmounting
131 * the backing file's underlying filesystem and could cause problems
132 * during system shutdown, for example. To prevent such problems, the
133 * thread catches INT, TERM, and KILL signals and converts them into
136 * In normal operation the main thread is started during the gadget's
137 * fsg_bind() callback and stopped during fsg_unbind(). But it can
138 * also exit when it receives a signal, and there's no point leaving
139 * the gadget running when the thread is dead. As of this moment, MSF
140 * provides no way to deregister the gadget when thread dies -- maybe
141 * a callback functions is needed.
143 * To provide maximum throughput, the driver uses a circular pipeline of
144 * buffer heads (struct fsg_buffhd). In principle the pipeline can be
145 * arbitrarily long; in practice the benefits don't justify having more
146 * than 2 stages (i.e., double buffering). But it helps to think of the
147 * pipeline as being a long one. Each buffer head contains a bulk-in and
148 * a bulk-out request pointer (since the buffer can be used for both
149 * output and input -- directions always are given from the host's
150 * point of view) as well as a pointer to the buffer and various state
153 * Use of the pipeline follows a simple protocol. There is a variable
154 * (fsg->next_buffhd_to_fill) that points to the next buffer head to use.
155 * At any time that buffer head may still be in use from an earlier
156 * request, so each buffer head has a state variable indicating whether
157 * it is EMPTY, FULL, or BUSY. Typical use involves waiting for the
158 * buffer head to be EMPTY, filling the buffer either by file I/O or by
159 * USB I/O (during which the buffer head is BUSY), and marking the buffer
160 * head FULL when the I/O is complete. Then the buffer will be emptied
161 * (again possibly by USB I/O, during which it is marked BUSY) and
162 * finally marked EMPTY again (possibly by a completion routine).
164 * A module parameter tells the driver to avoid stalling the bulk
165 * endpoints wherever the transport specification allows. This is
166 * necessary for some UDCs like the SuperH, which cannot reliably clear a
167 * halt on a bulk endpoint. However, under certain circumstances the
168 * Bulk-only specification requires a stall. In such cases the driver
169 * will halt the endpoint and set a flag indicating that it should clear
170 * the halt in software during the next device reset. Hopefully this
171 * will permit everything to work correctly. Furthermore, although the
172 * specification allows the bulk-out endpoint to halt when the host sends
173 * too much data, implementing this would cause an unavoidable race.
174 * The driver will always use the "no-stall" approach for OUT transfers.
176 * One subtle point concerns sending status-stage responses for ep0
177 * requests. Some of these requests, such as device reset, can involve
178 * interrupting an ongoing file I/O operation, which might take an
179 * arbitrarily long time. During that delay the host might give up on
180 * the original ep0 request and issue a new one. When that happens the
181 * driver should not notify the host about completion of the original
182 * request, as the host will no longer be waiting for it. So the driver
183 * assigns to each ep0 request a unique tag, and it keeps track of the
184 * tag value of the request associated with a long-running exception
185 * (device-reset, interface-change, or configuration-change). When the
186 * exception handler is finished, the status-stage response is submitted
187 * only if the current ep0 request tag is equal to the exception request
188 * tag. Thus only the most recently received ep0 request will get a
189 * status-stage response.
191 * Warning: This driver source file is too long. It ought to be split up
192 * into a header file plus about 3 separate .c files, to handle the details
193 * of the Gadget, USB Mass Storage, and SCSI protocols.
197 /* #define VERBOSE_DEBUG */
198 /* #define DUMP_MSGS */
200 #include <linux/blkdev.h>
201 #include <linux/completion.h>
202 #include <linux/dcache.h>
203 #include <linux/delay.h>
204 #include <linux/device.h>
205 #include <linux/fcntl.h>
206 #include <linux/file.h>
207 #include <linux/fs.h>
208 #include <linux/kref.h>
209 #include <linux/kthread.h>
210 #include <linux/limits.h>
211 #include <linux/rwsem.h>
212 #include <linux/slab.h>
213 #include <linux/spinlock.h>
214 #include <linux/string.h>
215 #include <linux/freezer.h>
216 #include <linux/module.h>
218 #include <linux/usb/ch9.h>
219 #include <linux/usb/gadget.h>
220 #include <linux/usb/composite.h>
222 #include "gadget_chips.h"
225 /*------------------------------------------------------------------------*/
227 #define FSG_DRIVER_DESC "Mass Storage Function"
228 #define FSG_DRIVER_VERSION "2009/09/11"
230 /* to avoid a lot of #ifndef-#endif in the temporary compatibility layer */
231 #ifndef USB_FMS_INCLUDED
232 #define EXPORT_SYMBOL_GPL_IF_MODULE(m) EXPORT_SYMBOL_GPL(m);
234 #define EXPORT_SYMBOL_GPL_IF_MODULE(m)
237 static const char fsg_string_interface[] = "Mass Storage";
239 #include "storage_common.h"
240 #include "f_mass_storage.h"
242 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
243 static struct usb_string fsg_strings[] = {
244 {FSG_STRING_INTERFACE, fsg_string_interface},
248 static struct usb_gadget_strings fsg_stringtab = {
249 .language = 0x0409, /* en-us */
250 .strings = fsg_strings,
253 static struct usb_gadget_strings *fsg_strings_array[] = {
258 /*-------------------------------------------------------------------------*/
263 /* Data shared by all the FSG instances. */
265 struct usb_gadget *gadget;
266 struct usb_composite_dev *cdev;
267 struct fsg_dev *fsg, *new_fsg;
268 wait_queue_head_t fsg_wait;
270 /* filesem protects: backing files in use */
271 struct rw_semaphore filesem;
273 /* lock protects: state, all the req_busy's */
276 struct usb_ep *ep0; /* Copy of gadget->ep0 */
277 struct usb_request *ep0req; /* Copy of cdev->req */
278 unsigned int ep0_req_tag;
280 struct fsg_buffhd *next_buffhd_to_fill;
281 struct fsg_buffhd *next_buffhd_to_drain;
282 struct fsg_buffhd *buffhds;
283 unsigned int fsg_num_buffers;
286 u8 cmnd[MAX_COMMAND_SIZE];
290 struct fsg_lun **luns;
291 struct fsg_lun *curlun;
293 unsigned int bulk_out_maxpacket;
294 enum fsg_state state; /* For exception handling */
295 unsigned int exception_req_tag;
297 enum data_direction data_dir;
299 u32 data_size_from_cmnd;
304 unsigned int can_stall:1;
305 unsigned int free_storage_on_release:1;
306 unsigned int phase_error:1;
307 unsigned int short_packet_received:1;
308 unsigned int bad_lun_okay:1;
309 unsigned int running:1;
310 unsigned int sysfs:1;
312 int thread_wakeup_needed;
313 struct completion thread_notifier;
314 struct task_struct *thread_task;
316 /* Callback functions. */
317 const struct fsg_operations *ops;
318 /* Gadget's private data. */
322 * Vendor (8 chars), product (16 chars), release (4
323 * hexadecimal digits) and NUL byte
325 char inquiry_string[8 + 16 + 4 + 1];
331 struct usb_function function;
332 struct usb_gadget *gadget; /* Copy of cdev->gadget */
333 struct fsg_common *common;
335 u16 interface_number;
337 unsigned int bulk_in_enabled:1;
338 unsigned int bulk_out_enabled:1;
340 unsigned long atomic_bitflags;
341 #define IGNORE_BULK_OUT 0
343 struct usb_ep *bulk_in;
344 struct usb_ep *bulk_out;
347 static inline int __fsg_is_set(struct fsg_common *common,
348 const char *func, unsigned line)
352 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
357 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
359 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
361 return container_of(f, struct fsg_dev, function);
364 typedef void (*fsg_routine_t)(struct fsg_dev *);
366 static int exception_in_progress(struct fsg_common *common)
368 return common->state > FSG_STATE_IDLE;
371 /* Make bulk-out requests be divisible by the maxpacket size */
372 static void set_bulk_out_req_length(struct fsg_common *common,
373 struct fsg_buffhd *bh, unsigned int length)
377 bh->bulk_out_intended_length = length;
378 rem = length % common->bulk_out_maxpacket;
380 length += common->bulk_out_maxpacket - rem;
381 bh->outreq->length = length;
385 /*-------------------------------------------------------------------------*/
387 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
391 if (ep == fsg->bulk_in)
393 else if (ep == fsg->bulk_out)
397 DBG(fsg, "%s set halt\n", name);
398 return usb_ep_set_halt(ep);
402 /*-------------------------------------------------------------------------*/
404 /* These routines may be called in process context or in_irq */
406 /* Caller must hold fsg->lock */
407 static void wakeup_thread(struct fsg_common *common)
409 smp_wmb(); /* ensure the write of bh->state is complete */
410 /* Tell the main thread that something has happened */
411 common->thread_wakeup_needed = 1;
412 if (common->thread_task)
413 wake_up_process(common->thread_task);
416 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
421 * Do nothing if a higher-priority exception is already in progress.
422 * If a lower-or-equal priority exception is in progress, preempt it
423 * and notify the main thread by sending it a signal.
425 spin_lock_irqsave(&common->lock, flags);
426 if (common->state <= new_state) {
427 common->exception_req_tag = common->ep0_req_tag;
428 common->state = new_state;
429 if (common->thread_task)
430 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
431 common->thread_task);
433 spin_unlock_irqrestore(&common->lock, flags);
437 /*-------------------------------------------------------------------------*/
439 static int ep0_queue(struct fsg_common *common)
443 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
444 common->ep0->driver_data = common;
445 if (rc != 0 && rc != -ESHUTDOWN) {
446 /* We can't do much more than wait for a reset */
447 WARNING(common, "error in submission: %s --> %d\n",
448 common->ep0->name, rc);
454 /*-------------------------------------------------------------------------*/
456 /* Completion handlers. These always run in_irq. */
458 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
460 struct fsg_common *common = ep->driver_data;
461 struct fsg_buffhd *bh = req->context;
463 if (req->status || req->actual != req->length)
464 DBG(common, "%s --> %d, %u/%u\n", __func__,
465 req->status, req->actual, req->length);
466 if (req->status == -ECONNRESET) /* Request was cancelled */
467 usb_ep_fifo_flush(ep);
469 /* Hold the lock while we update the request and buffer states */
471 spin_lock(&common->lock);
473 bh->state = BUF_STATE_EMPTY;
474 wakeup_thread(common);
475 spin_unlock(&common->lock);
478 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
480 struct fsg_common *common = ep->driver_data;
481 struct fsg_buffhd *bh = req->context;
483 dump_msg(common, "bulk-out", req->buf, req->actual);
484 if (req->status || req->actual != bh->bulk_out_intended_length)
485 DBG(common, "%s --> %d, %u/%u\n", __func__,
486 req->status, req->actual, bh->bulk_out_intended_length);
487 if (req->status == -ECONNRESET) /* Request was cancelled */
488 usb_ep_fifo_flush(ep);
490 /* Hold the lock while we update the request and buffer states */
492 spin_lock(&common->lock);
494 bh->state = BUF_STATE_FULL;
495 wakeup_thread(common);
496 spin_unlock(&common->lock);
499 static int fsg_setup(struct usb_function *f,
500 const struct usb_ctrlrequest *ctrl)
502 struct fsg_dev *fsg = fsg_from_func(f);
503 struct usb_request *req = fsg->common->ep0req;
504 u16 w_index = le16_to_cpu(ctrl->wIndex);
505 u16 w_value = le16_to_cpu(ctrl->wValue);
506 u16 w_length = le16_to_cpu(ctrl->wLength);
508 if (!fsg_is_set(fsg->common))
511 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
514 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
516 switch (ctrl->bRequest) {
518 case US_BULK_RESET_REQUEST:
519 if (ctrl->bRequestType !=
520 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
522 if (w_index != fsg->interface_number || w_value != 0 ||
527 * Raise an exception to stop the current operation
528 * and reinitialize our state.
530 DBG(fsg, "bulk reset request\n");
531 raise_exception(fsg->common, FSG_STATE_RESET);
532 return DELAYED_STATUS;
534 case US_BULK_GET_MAX_LUN:
535 if (ctrl->bRequestType !=
536 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
538 if (w_index != fsg->interface_number || w_value != 0 ||
541 VDBG(fsg, "get max LUN\n");
542 *(u8 *)req->buf = fsg->common->nluns - 1;
544 /* Respond with data/status */
545 req->length = min((u16)1, w_length);
546 return ep0_queue(fsg->common);
550 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
551 ctrl->bRequestType, ctrl->bRequest,
552 le16_to_cpu(ctrl->wValue), w_index, w_length);
557 /*-------------------------------------------------------------------------*/
559 /* All the following routines run in process context */
561 /* Use this for bulk or interrupt transfers, not ep0 */
562 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
563 struct usb_request *req, int *pbusy,
564 enum fsg_buffer_state *state)
568 if (ep == fsg->bulk_in)
569 dump_msg(fsg, "bulk-in", req->buf, req->length);
571 spin_lock_irq(&fsg->common->lock);
573 *state = BUF_STATE_BUSY;
574 spin_unlock_irq(&fsg->common->lock);
575 rc = usb_ep_queue(ep, req, GFP_KERNEL);
578 *state = BUF_STATE_EMPTY;
580 /* We can't do much more than wait for a reset */
583 * Note: currently the net2280 driver fails zero-length
584 * submissions if DMA is enabled.
586 if (rc != -ESHUTDOWN &&
587 !(rc == -EOPNOTSUPP && req->length == 0))
588 WARNING(fsg, "error in submission: %s --> %d\n",
593 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
595 if (!fsg_is_set(common))
597 start_transfer(common->fsg, common->fsg->bulk_in,
598 bh->inreq, &bh->inreq_busy, &bh->state);
602 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
604 if (!fsg_is_set(common))
606 start_transfer(common->fsg, common->fsg->bulk_out,
607 bh->outreq, &bh->outreq_busy, &bh->state);
611 static int sleep_thread(struct fsg_common *common)
615 /* Wait until a signal arrives or we are woken up */
618 set_current_state(TASK_INTERRUPTIBLE);
619 if (signal_pending(current)) {
623 if (common->thread_wakeup_needed)
627 __set_current_state(TASK_RUNNING);
628 common->thread_wakeup_needed = 0;
629 smp_rmb(); /* ensure the latest bh->state is visible */
634 /*-------------------------------------------------------------------------*/
636 static int do_read(struct fsg_common *common)
638 struct fsg_lun *curlun = common->curlun;
640 struct fsg_buffhd *bh;
643 loff_t file_offset, file_offset_tmp;
648 * Get the starting Logical Block Address and check that it's
651 if (common->cmnd[0] == READ_6)
652 lba = get_unaligned_be24(&common->cmnd[1]);
654 lba = get_unaligned_be32(&common->cmnd[2]);
657 * We allow DPO (Disable Page Out = don't save data in the
658 * cache) and FUA (Force Unit Access = don't read from the
659 * cache), but we don't implement them.
661 if ((common->cmnd[1] & ~0x18) != 0) {
662 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
666 if (lba >= curlun->num_sectors) {
667 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
670 file_offset = ((loff_t) lba) << curlun->blkbits;
672 /* Carry out the file reads */
673 amount_left = common->data_size_from_cmnd;
674 if (unlikely(amount_left == 0))
675 return -EIO; /* No default reply */
679 * Figure out how much we need to read:
680 * Try to read the remaining amount.
681 * But don't read more than the buffer size.
682 * And don't try to read past the end of the file.
684 amount = min(amount_left, FSG_BUFLEN);
685 amount = min((loff_t)amount,
686 curlun->file_length - file_offset);
688 /* Wait for the next buffer to become available */
689 bh = common->next_buffhd_to_fill;
690 while (bh->state != BUF_STATE_EMPTY) {
691 rc = sleep_thread(common);
697 * If we were asked to read past the end of file,
698 * end with an empty buffer.
702 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
703 curlun->sense_data_info =
704 file_offset >> curlun->blkbits;
705 curlun->info_valid = 1;
706 bh->inreq->length = 0;
707 bh->state = BUF_STATE_FULL;
711 /* Perform the read */
712 file_offset_tmp = file_offset;
713 nread = vfs_read(curlun->filp,
714 (char __user *)bh->buf,
715 amount, &file_offset_tmp);
716 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
717 (unsigned long long)file_offset, (int)nread);
718 if (signal_pending(current))
722 LDBG(curlun, "error in file read: %d\n", (int)nread);
724 } else if (nread < amount) {
725 LDBG(curlun, "partial file read: %d/%u\n",
727 nread = round_down(nread, curlun->blksize);
729 file_offset += nread;
730 amount_left -= nread;
731 common->residue -= nread;
734 * Except at the end of the transfer, nread will be
735 * equal to the buffer size, which is divisible by the
736 * bulk-in maxpacket size.
738 bh->inreq->length = nread;
739 bh->state = BUF_STATE_FULL;
741 /* If an error occurred, report it and its position */
742 if (nread < amount) {
743 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
744 curlun->sense_data_info =
745 file_offset >> curlun->blkbits;
746 curlun->info_valid = 1;
750 if (amount_left == 0)
751 break; /* No more left to read */
753 /* Send this buffer and go read some more */
755 if (!start_in_transfer(common, bh))
756 /* Don't know what to do if common->fsg is NULL */
758 common->next_buffhd_to_fill = bh->next;
761 return -EIO; /* No default reply */
765 /*-------------------------------------------------------------------------*/
767 static int do_write(struct fsg_common *common)
769 struct fsg_lun *curlun = common->curlun;
771 struct fsg_buffhd *bh;
773 u32 amount_left_to_req, amount_left_to_write;
774 loff_t usb_offset, file_offset, file_offset_tmp;
780 curlun->sense_data = SS_WRITE_PROTECTED;
783 spin_lock(&curlun->filp->f_lock);
784 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
785 spin_unlock(&curlun->filp->f_lock);
788 * Get the starting Logical Block Address and check that it's
791 if (common->cmnd[0] == WRITE_6)
792 lba = get_unaligned_be24(&common->cmnd[1]);
794 lba = get_unaligned_be32(&common->cmnd[2]);
797 * We allow DPO (Disable Page Out = don't save data in the
798 * cache) and FUA (Force Unit Access = write directly to the
799 * medium). We don't implement DPO; we implement FUA by
800 * performing synchronous output.
802 if (common->cmnd[1] & ~0x18) {
803 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
806 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
807 spin_lock(&curlun->filp->f_lock);
808 curlun->filp->f_flags |= O_SYNC;
809 spin_unlock(&curlun->filp->f_lock);
812 if (lba >= curlun->num_sectors) {
813 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
817 /* Carry out the file writes */
819 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
820 amount_left_to_req = common->data_size_from_cmnd;
821 amount_left_to_write = common->data_size_from_cmnd;
823 while (amount_left_to_write > 0) {
825 /* Queue a request for more data from the host */
826 bh = common->next_buffhd_to_fill;
827 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
830 * Figure out how much we want to get:
831 * Try to get the remaining amount,
832 * but not more than the buffer size.
834 amount = min(amount_left_to_req, FSG_BUFLEN);
836 /* Beyond the end of the backing file? */
837 if (usb_offset >= curlun->file_length) {
840 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
841 curlun->sense_data_info =
842 usb_offset >> curlun->blkbits;
843 curlun->info_valid = 1;
847 /* Get the next buffer */
848 usb_offset += amount;
849 common->usb_amount_left -= amount;
850 amount_left_to_req -= amount;
851 if (amount_left_to_req == 0)
855 * Except at the end of the transfer, amount will be
856 * equal to the buffer size, which is divisible by
857 * the bulk-out maxpacket size.
859 set_bulk_out_req_length(common, bh, amount);
860 if (!start_out_transfer(common, bh))
861 /* Dunno what to do if common->fsg is NULL */
863 common->next_buffhd_to_fill = bh->next;
867 /* Write the received data to the backing file */
868 bh = common->next_buffhd_to_drain;
869 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
870 break; /* We stopped early */
871 if (bh->state == BUF_STATE_FULL) {
873 common->next_buffhd_to_drain = bh->next;
874 bh->state = BUF_STATE_EMPTY;
876 /* Did something go wrong with the transfer? */
877 if (bh->outreq->status != 0) {
878 curlun->sense_data = SS_COMMUNICATION_FAILURE;
879 curlun->sense_data_info =
880 file_offset >> curlun->blkbits;
881 curlun->info_valid = 1;
885 amount = bh->outreq->actual;
886 if (curlun->file_length - file_offset < amount) {
888 "write %u @ %llu beyond end %llu\n",
889 amount, (unsigned long long)file_offset,
890 (unsigned long long)curlun->file_length);
891 amount = curlun->file_length - file_offset;
894 /* Don't accept excess data. The spec doesn't say
895 * what to do in this case. We'll ignore the error.
897 amount = min(amount, bh->bulk_out_intended_length);
899 /* Don't write a partial block */
900 amount = round_down(amount, curlun->blksize);
904 /* Perform the write */
905 file_offset_tmp = file_offset;
906 nwritten = vfs_write(curlun->filp,
907 (char __user *)bh->buf,
908 amount, &file_offset_tmp);
909 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
910 (unsigned long long)file_offset, (int)nwritten);
911 if (signal_pending(current))
912 return -EINTR; /* Interrupted! */
915 LDBG(curlun, "error in file write: %d\n",
918 } else if (nwritten < amount) {
919 LDBG(curlun, "partial file write: %d/%u\n",
920 (int)nwritten, amount);
921 nwritten = round_down(nwritten, curlun->blksize);
923 file_offset += nwritten;
924 amount_left_to_write -= nwritten;
925 common->residue -= nwritten;
927 /* If an error occurred, report it and its position */
928 if (nwritten < amount) {
929 curlun->sense_data = SS_WRITE_ERROR;
930 curlun->sense_data_info =
931 file_offset >> curlun->blkbits;
932 curlun->info_valid = 1;
937 /* Did the host decide to stop early? */
938 if (bh->outreq->actual < bh->bulk_out_intended_length) {
939 common->short_packet_received = 1;
945 /* Wait for something to happen */
946 rc = sleep_thread(common);
951 return -EIO; /* No default reply */
955 /*-------------------------------------------------------------------------*/
957 static int do_synchronize_cache(struct fsg_common *common)
959 struct fsg_lun *curlun = common->curlun;
962 /* We ignore the requested LBA and write out all file's
963 * dirty data buffers. */
964 rc = fsg_lun_fsync_sub(curlun);
966 curlun->sense_data = SS_WRITE_ERROR;
971 /*-------------------------------------------------------------------------*/
973 static void invalidate_sub(struct fsg_lun *curlun)
975 struct file *filp = curlun->filp;
976 struct inode *inode = file_inode(filp);
979 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
980 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
983 static int do_verify(struct fsg_common *common)
985 struct fsg_lun *curlun = common->curlun;
987 u32 verification_length;
988 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
989 loff_t file_offset, file_offset_tmp;
995 * Get the starting Logical Block Address and check that it's
998 lba = get_unaligned_be32(&common->cmnd[2]);
999 if (lba >= curlun->num_sectors) {
1000 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1005 * We allow DPO (Disable Page Out = don't save data in the
1006 * cache) but we don't implement it.
1008 if (common->cmnd[1] & ~0x10) {
1009 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1013 verification_length = get_unaligned_be16(&common->cmnd[7]);
1014 if (unlikely(verification_length == 0))
1015 return -EIO; /* No default reply */
1017 /* Prepare to carry out the file verify */
1018 amount_left = verification_length << curlun->blkbits;
1019 file_offset = ((loff_t) lba) << curlun->blkbits;
1021 /* Write out all the dirty buffers before invalidating them */
1022 fsg_lun_fsync_sub(curlun);
1023 if (signal_pending(current))
1026 invalidate_sub(curlun);
1027 if (signal_pending(current))
1030 /* Just try to read the requested blocks */
1031 while (amount_left > 0) {
1033 * Figure out how much we need to read:
1034 * Try to read the remaining amount, but not more than
1036 * And don't try to read past the end of the file.
1038 amount = min(amount_left, FSG_BUFLEN);
1039 amount = min((loff_t)amount,
1040 curlun->file_length - file_offset);
1042 curlun->sense_data =
1043 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1044 curlun->sense_data_info =
1045 file_offset >> curlun->blkbits;
1046 curlun->info_valid = 1;
1050 /* Perform the read */
1051 file_offset_tmp = file_offset;
1052 nread = vfs_read(curlun->filp,
1053 (char __user *) bh->buf,
1054 amount, &file_offset_tmp);
1055 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1056 (unsigned long long) file_offset,
1058 if (signal_pending(current))
1062 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1064 } else if (nread < amount) {
1065 LDBG(curlun, "partial file verify: %d/%u\n",
1066 (int)nread, amount);
1067 nread = round_down(nread, curlun->blksize);
1070 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1071 curlun->sense_data_info =
1072 file_offset >> curlun->blkbits;
1073 curlun->info_valid = 1;
1076 file_offset += nread;
1077 amount_left -= nread;
1083 /*-------------------------------------------------------------------------*/
1085 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1087 struct fsg_lun *curlun = common->curlun;
1088 u8 *buf = (u8 *) bh->buf;
1090 if (!curlun) { /* Unsupported LUNs are okay */
1091 common->bad_lun_okay = 1;
1093 buf[0] = 0x7f; /* Unsupported, no device-type */
1094 buf[4] = 31; /* Additional length */
1098 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1099 buf[1] = curlun->removable ? 0x80 : 0;
1100 buf[2] = 2; /* ANSI SCSI level 2 */
1101 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1102 buf[4] = 31; /* Additional length */
1103 buf[5] = 0; /* No special options */
1106 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1110 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1112 struct fsg_lun *curlun = common->curlun;
1113 u8 *buf = (u8 *) bh->buf;
1118 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1120 * If a REQUEST SENSE command is received from an initiator
1121 * with a pending unit attention condition (before the target
1122 * generates the contingent allegiance condition), then the
1123 * target shall either:
1124 * a) report any pending sense data and preserve the unit
1125 * attention condition on the logical unit, or,
1126 * b) report the unit attention condition, may discard any
1127 * pending sense data, and clear the unit attention
1128 * condition on the logical unit for that initiator.
1130 * FSG normally uses option a); enable this code to use option b).
1133 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1134 curlun->sense_data = curlun->unit_attention_data;
1135 curlun->unit_attention_data = SS_NO_SENSE;
1139 if (!curlun) { /* Unsupported LUNs are okay */
1140 common->bad_lun_okay = 1;
1141 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1145 sd = curlun->sense_data;
1146 sdinfo = curlun->sense_data_info;
1147 valid = curlun->info_valid << 7;
1148 curlun->sense_data = SS_NO_SENSE;
1149 curlun->sense_data_info = 0;
1150 curlun->info_valid = 0;
1154 buf[0] = valid | 0x70; /* Valid, current error */
1156 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1157 buf[7] = 18 - 8; /* Additional sense length */
1163 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1165 struct fsg_lun *curlun = common->curlun;
1166 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1167 int pmi = common->cmnd[8];
1168 u8 *buf = (u8 *)bh->buf;
1170 /* Check the PMI and LBA fields */
1171 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1172 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1176 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1177 /* Max logical block */
1178 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1182 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1184 struct fsg_lun *curlun = common->curlun;
1185 int msf = common->cmnd[1] & 0x02;
1186 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1187 u8 *buf = (u8 *)bh->buf;
1189 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1190 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1193 if (lba >= curlun->num_sectors) {
1194 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1199 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1200 store_cdrom_address(&buf[4], msf, lba);
1204 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1206 struct fsg_lun *curlun = common->curlun;
1207 int msf = common->cmnd[1] & 0x02;
1208 int start_track = common->cmnd[6];
1209 u8 *buf = (u8 *)bh->buf;
1211 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1213 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1218 buf[1] = (20-2); /* TOC data length */
1219 buf[2] = 1; /* First track number */
1220 buf[3] = 1; /* Last track number */
1221 buf[5] = 0x16; /* Data track, copying allowed */
1222 buf[6] = 0x01; /* Only track is number 1 */
1223 store_cdrom_address(&buf[8], msf, 0);
1225 buf[13] = 0x16; /* Lead-out track is data */
1226 buf[14] = 0xAA; /* Lead-out track number */
1227 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1231 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1233 struct fsg_lun *curlun = common->curlun;
1234 int mscmnd = common->cmnd[0];
1235 u8 *buf = (u8 *) bh->buf;
1238 int changeable_values, all_pages;
1242 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1243 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1246 pc = common->cmnd[2] >> 6;
1247 page_code = common->cmnd[2] & 0x3f;
1249 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1252 changeable_values = (pc == 1);
1253 all_pages = (page_code == 0x3f);
1256 * Write the mode parameter header. Fixed values are: default
1257 * medium type, no cache control (DPOFUA), and no block descriptors.
1258 * The only variable value is the WriteProtect bit. We will fill in
1259 * the mode data length later.
1262 if (mscmnd == MODE_SENSE) {
1263 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1266 } else { /* MODE_SENSE_10 */
1267 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1269 limit = 65535; /* Should really be FSG_BUFLEN */
1272 /* No block descriptors */
1275 * The mode pages, in numerical order. The only page we support
1276 * is the Caching page.
1278 if (page_code == 0x08 || all_pages) {
1280 buf[0] = 0x08; /* Page code */
1281 buf[1] = 10; /* Page length */
1282 memset(buf+2, 0, 10); /* None of the fields are changeable */
1284 if (!changeable_values) {
1285 buf[2] = 0x04; /* Write cache enable, */
1286 /* Read cache not disabled */
1287 /* No cache retention priorities */
1288 put_unaligned_be16(0xffff, &buf[4]);
1289 /* Don't disable prefetch */
1290 /* Minimum prefetch = 0 */
1291 put_unaligned_be16(0xffff, &buf[8]);
1292 /* Maximum prefetch */
1293 put_unaligned_be16(0xffff, &buf[10]);
1294 /* Maximum prefetch ceiling */
1300 * Check that a valid page was requested and the mode data length
1304 if (!valid_page || len > limit) {
1305 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1309 /* Store the mode data length */
1310 if (mscmnd == MODE_SENSE)
1313 put_unaligned_be16(len - 2, buf0);
1317 static int do_start_stop(struct fsg_common *common)
1319 struct fsg_lun *curlun = common->curlun;
1324 } else if (!curlun->removable) {
1325 curlun->sense_data = SS_INVALID_COMMAND;
1327 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1328 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1329 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1333 loej = common->cmnd[4] & 0x02;
1334 start = common->cmnd[4] & 0x01;
1337 * Our emulation doesn't support mounting; the medium is
1338 * available for use as soon as it is loaded.
1341 if (!fsg_lun_is_open(curlun)) {
1342 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1348 /* Are we allowed to unload the media? */
1349 if (curlun->prevent_medium_removal) {
1350 LDBG(curlun, "unload attempt prevented\n");
1351 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1358 up_read(&common->filesem);
1359 down_write(&common->filesem);
1360 fsg_lun_close(curlun);
1361 up_write(&common->filesem);
1362 down_read(&common->filesem);
1367 static int do_prevent_allow(struct fsg_common *common)
1369 struct fsg_lun *curlun = common->curlun;
1372 if (!common->curlun) {
1374 } else if (!common->curlun->removable) {
1375 common->curlun->sense_data = SS_INVALID_COMMAND;
1379 prevent = common->cmnd[4] & 0x01;
1380 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1381 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1385 if (curlun->prevent_medium_removal && !prevent)
1386 fsg_lun_fsync_sub(curlun);
1387 curlun->prevent_medium_removal = prevent;
1391 static int do_read_format_capacities(struct fsg_common *common,
1392 struct fsg_buffhd *bh)
1394 struct fsg_lun *curlun = common->curlun;
1395 u8 *buf = (u8 *) bh->buf;
1397 buf[0] = buf[1] = buf[2] = 0;
1398 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1401 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1402 /* Number of blocks */
1403 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1404 buf[4] = 0x02; /* Current capacity */
1408 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1410 struct fsg_lun *curlun = common->curlun;
1412 /* We don't support MODE SELECT */
1414 curlun->sense_data = SS_INVALID_COMMAND;
1419 /*-------------------------------------------------------------------------*/
1421 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1425 rc = fsg_set_halt(fsg, fsg->bulk_in);
1427 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1429 if (rc != -EAGAIN) {
1430 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1435 /* Wait for a short time and then try again */
1436 if (msleep_interruptible(100) != 0)
1438 rc = usb_ep_set_halt(fsg->bulk_in);
1443 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1447 DBG(fsg, "bulk-in set wedge\n");
1448 rc = usb_ep_set_wedge(fsg->bulk_in);
1450 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1452 if (rc != -EAGAIN) {
1453 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1458 /* Wait for a short time and then try again */
1459 if (msleep_interruptible(100) != 0)
1461 rc = usb_ep_set_wedge(fsg->bulk_in);
1466 static int throw_away_data(struct fsg_common *common)
1468 struct fsg_buffhd *bh;
1472 for (bh = common->next_buffhd_to_drain;
1473 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1474 bh = common->next_buffhd_to_drain) {
1476 /* Throw away the data in a filled buffer */
1477 if (bh->state == BUF_STATE_FULL) {
1479 bh->state = BUF_STATE_EMPTY;
1480 common->next_buffhd_to_drain = bh->next;
1482 /* A short packet or an error ends everything */
1483 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1484 bh->outreq->status != 0) {
1485 raise_exception(common,
1486 FSG_STATE_ABORT_BULK_OUT);
1492 /* Try to submit another request if we need one */
1493 bh = common->next_buffhd_to_fill;
1494 if (bh->state == BUF_STATE_EMPTY
1495 && common->usb_amount_left > 0) {
1496 amount = min(common->usb_amount_left, FSG_BUFLEN);
1499 * Except at the end of the transfer, amount will be
1500 * equal to the buffer size, which is divisible by
1501 * the bulk-out maxpacket size.
1503 set_bulk_out_req_length(common, bh, amount);
1504 if (!start_out_transfer(common, bh))
1505 /* Dunno what to do if common->fsg is NULL */
1507 common->next_buffhd_to_fill = bh->next;
1508 common->usb_amount_left -= amount;
1512 /* Otherwise wait for something to happen */
1513 rc = sleep_thread(common);
1520 static int finish_reply(struct fsg_common *common)
1522 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1525 switch (common->data_dir) {
1527 break; /* Nothing to send */
1530 * If we don't know whether the host wants to read or write,
1531 * this must be CB or CBI with an unknown command. We mustn't
1532 * try to send or receive any data. So stall both bulk pipes
1533 * if we can and wait for a reset.
1535 case DATA_DIR_UNKNOWN:
1536 if (!common->can_stall) {
1538 } else if (fsg_is_set(common)) {
1539 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1540 rc = halt_bulk_in_endpoint(common->fsg);
1542 /* Don't know what to do if common->fsg is NULL */
1547 /* All but the last buffer of data must have already been sent */
1548 case DATA_DIR_TO_HOST:
1549 if (common->data_size == 0) {
1550 /* Nothing to send */
1552 /* Don't know what to do if common->fsg is NULL */
1553 } else if (!fsg_is_set(common)) {
1556 /* If there's no residue, simply send the last buffer */
1557 } else if (common->residue == 0) {
1558 bh->inreq->zero = 0;
1559 if (!start_in_transfer(common, bh))
1561 common->next_buffhd_to_fill = bh->next;
1564 * For Bulk-only, mark the end of the data with a short
1565 * packet. If we are allowed to stall, halt the bulk-in
1566 * endpoint. (Note: This violates the Bulk-Only Transport
1567 * specification, which requires us to pad the data if we
1568 * don't halt the endpoint. Presumably nobody will mind.)
1571 bh->inreq->zero = 1;
1572 if (!start_in_transfer(common, bh))
1574 common->next_buffhd_to_fill = bh->next;
1575 if (common->can_stall)
1576 rc = halt_bulk_in_endpoint(common->fsg);
1581 * We have processed all we want from the data the host has sent.
1582 * There may still be outstanding bulk-out requests.
1584 case DATA_DIR_FROM_HOST:
1585 if (common->residue == 0) {
1586 /* Nothing to receive */
1588 /* Did the host stop sending unexpectedly early? */
1589 } else if (common->short_packet_received) {
1590 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1594 * We haven't processed all the incoming data. Even though
1595 * we may be allowed to stall, doing so would cause a race.
1596 * The controller may already have ACK'ed all the remaining
1597 * bulk-out packets, in which case the host wouldn't see a
1598 * STALL. Not realizing the endpoint was halted, it wouldn't
1599 * clear the halt -- leading to problems later on.
1602 } else if (common->can_stall) {
1603 if (fsg_is_set(common))
1604 fsg_set_halt(common->fsg,
1605 common->fsg->bulk_out);
1606 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1611 * We can't stall. Read in the excess data and throw it
1615 rc = throw_away_data(common);
1622 static int send_status(struct fsg_common *common)
1624 struct fsg_lun *curlun = common->curlun;
1625 struct fsg_buffhd *bh;
1626 struct bulk_cs_wrap *csw;
1628 u8 status = US_BULK_STAT_OK;
1631 /* Wait for the next buffer to become available */
1632 bh = common->next_buffhd_to_fill;
1633 while (bh->state != BUF_STATE_EMPTY) {
1634 rc = sleep_thread(common);
1640 sd = curlun->sense_data;
1641 sdinfo = curlun->sense_data_info;
1642 } else if (common->bad_lun_okay)
1645 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1647 if (common->phase_error) {
1648 DBG(common, "sending phase-error status\n");
1649 status = US_BULK_STAT_PHASE;
1650 sd = SS_INVALID_COMMAND;
1651 } else if (sd != SS_NO_SENSE) {
1652 DBG(common, "sending command-failure status\n");
1653 status = US_BULK_STAT_FAIL;
1654 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1656 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1659 /* Store and send the Bulk-only CSW */
1660 csw = (void *)bh->buf;
1662 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1663 csw->Tag = common->tag;
1664 csw->Residue = cpu_to_le32(common->residue);
1665 csw->Status = status;
1667 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1668 bh->inreq->zero = 0;
1669 if (!start_in_transfer(common, bh))
1670 /* Don't know what to do if common->fsg is NULL */
1673 common->next_buffhd_to_fill = bh->next;
1678 /*-------------------------------------------------------------------------*/
1681 * Check whether the command is properly formed and whether its data size
1682 * and direction agree with the values we already have.
1684 static int check_command(struct fsg_common *common, int cmnd_size,
1685 enum data_direction data_dir, unsigned int mask,
1686 int needs_medium, const char *name)
1689 unsigned int lun = common->cmnd[1] >> 5;
1690 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1692 struct fsg_lun *curlun;
1695 if (common->data_dir != DATA_DIR_UNKNOWN)
1696 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1698 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1699 name, cmnd_size, dirletter[(int) data_dir],
1700 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1703 * We can't reply at all until we know the correct data direction
1706 if (common->data_size_from_cmnd == 0)
1707 data_dir = DATA_DIR_NONE;
1708 if (common->data_size < common->data_size_from_cmnd) {
1710 * Host data size < Device data size is a phase error.
1711 * Carry out the command, but only transfer as much as
1714 common->data_size_from_cmnd = common->data_size;
1715 common->phase_error = 1;
1717 common->residue = common->data_size;
1718 common->usb_amount_left = common->data_size;
1720 /* Conflicting data directions is a phase error */
1721 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1722 common->phase_error = 1;
1726 /* Verify the length of the command itself */
1727 if (cmnd_size != common->cmnd_size) {
1730 * Special case workaround: There are plenty of buggy SCSI
1731 * implementations. Many have issues with cbw->Length
1732 * field passing a wrong command size. For those cases we
1733 * always try to work around the problem by using the length
1734 * sent by the host side provided it is at least as large
1735 * as the correct command length.
1736 * Examples of such cases would be MS-Windows, which issues
1737 * REQUEST SENSE with cbw->Length == 12 where it should
1738 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1739 * REQUEST SENSE with cbw->Length == 10 where it should
1742 if (cmnd_size <= common->cmnd_size) {
1743 DBG(common, "%s is buggy! Expected length %d "
1744 "but we got %d\n", name,
1745 cmnd_size, common->cmnd_size);
1746 cmnd_size = common->cmnd_size;
1748 common->phase_error = 1;
1753 /* Check that the LUN values are consistent */
1754 if (common->lun != lun)
1755 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1759 curlun = common->curlun;
1761 if (common->cmnd[0] != REQUEST_SENSE) {
1762 curlun->sense_data = SS_NO_SENSE;
1763 curlun->sense_data_info = 0;
1764 curlun->info_valid = 0;
1767 common->bad_lun_okay = 0;
1770 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1771 * to use unsupported LUNs; all others may not.
1773 if (common->cmnd[0] != INQUIRY &&
1774 common->cmnd[0] != REQUEST_SENSE) {
1775 DBG(common, "unsupported LUN %u\n", common->lun);
1781 * If a unit attention condition exists, only INQUIRY and
1782 * REQUEST SENSE commands are allowed; anything else must fail.
1784 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1785 common->cmnd[0] != INQUIRY &&
1786 common->cmnd[0] != REQUEST_SENSE) {
1787 curlun->sense_data = curlun->unit_attention_data;
1788 curlun->unit_attention_data = SS_NO_SENSE;
1792 /* Check that only command bytes listed in the mask are non-zero */
1793 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1794 for (i = 1; i < cmnd_size; ++i) {
1795 if (common->cmnd[i] && !(mask & (1 << i))) {
1797 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1802 /* If the medium isn't mounted and the command needs to access
1803 * it, return an error. */
1804 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1805 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1812 /* wrapper of check_command for data size in blocks handling */
1813 static int check_command_size_in_blocks(struct fsg_common *common,
1814 int cmnd_size, enum data_direction data_dir,
1815 unsigned int mask, int needs_medium, const char *name)
1818 common->data_size_from_cmnd <<= common->curlun->blkbits;
1819 return check_command(common, cmnd_size, data_dir,
1820 mask, needs_medium, name);
1823 static int do_scsi_command(struct fsg_common *common)
1825 struct fsg_buffhd *bh;
1827 int reply = -EINVAL;
1829 static char unknown[16];
1833 /* Wait for the next buffer to become available for data or status */
1834 bh = common->next_buffhd_to_fill;
1835 common->next_buffhd_to_drain = bh;
1836 while (bh->state != BUF_STATE_EMPTY) {
1837 rc = sleep_thread(common);
1841 common->phase_error = 0;
1842 common->short_packet_received = 0;
1844 down_read(&common->filesem); /* We're using the backing file */
1845 switch (common->cmnd[0]) {
1848 common->data_size_from_cmnd = common->cmnd[4];
1849 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1853 reply = do_inquiry(common, bh);
1857 common->data_size_from_cmnd = common->cmnd[4];
1858 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1862 reply = do_mode_select(common, bh);
1865 case MODE_SELECT_10:
1866 common->data_size_from_cmnd =
1867 get_unaligned_be16(&common->cmnd[7]);
1868 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1872 reply = do_mode_select(common, bh);
1876 common->data_size_from_cmnd = common->cmnd[4];
1877 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1878 (1<<1) | (1<<2) | (1<<4), 0,
1881 reply = do_mode_sense(common, bh);
1885 common->data_size_from_cmnd =
1886 get_unaligned_be16(&common->cmnd[7]);
1887 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1888 (1<<1) | (1<<2) | (3<<7), 0,
1891 reply = do_mode_sense(common, bh);
1894 case ALLOW_MEDIUM_REMOVAL:
1895 common->data_size_from_cmnd = 0;
1896 reply = check_command(common, 6, DATA_DIR_NONE,
1898 "PREVENT-ALLOW MEDIUM REMOVAL");
1900 reply = do_prevent_allow(common);
1904 i = common->cmnd[4];
1905 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1906 reply = check_command_size_in_blocks(common, 6,
1911 reply = do_read(common);
1915 common->data_size_from_cmnd =
1916 get_unaligned_be16(&common->cmnd[7]);
1917 reply = check_command_size_in_blocks(common, 10,
1919 (1<<1) | (0xf<<2) | (3<<7), 1,
1922 reply = do_read(common);
1926 common->data_size_from_cmnd =
1927 get_unaligned_be32(&common->cmnd[6]);
1928 reply = check_command_size_in_blocks(common, 12,
1930 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1933 reply = do_read(common);
1937 common->data_size_from_cmnd = 8;
1938 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1939 (0xf<<2) | (1<<8), 1,
1942 reply = do_read_capacity(common, bh);
1946 if (!common->curlun || !common->curlun->cdrom)
1948 common->data_size_from_cmnd =
1949 get_unaligned_be16(&common->cmnd[7]);
1950 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1951 (3<<7) | (0x1f<<1), 1,
1954 reply = do_read_header(common, bh);
1958 if (!common->curlun || !common->curlun->cdrom)
1960 common->data_size_from_cmnd =
1961 get_unaligned_be16(&common->cmnd[7]);
1962 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1966 reply = do_read_toc(common, bh);
1969 case READ_FORMAT_CAPACITIES:
1970 common->data_size_from_cmnd =
1971 get_unaligned_be16(&common->cmnd[7]);
1972 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1974 "READ FORMAT CAPACITIES");
1976 reply = do_read_format_capacities(common, bh);
1980 common->data_size_from_cmnd = common->cmnd[4];
1981 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1985 reply = do_request_sense(common, bh);
1989 common->data_size_from_cmnd = 0;
1990 reply = check_command(common, 6, DATA_DIR_NONE,
1994 reply = do_start_stop(common);
1997 case SYNCHRONIZE_CACHE:
1998 common->data_size_from_cmnd = 0;
1999 reply = check_command(common, 10, DATA_DIR_NONE,
2000 (0xf<<2) | (3<<7), 1,
2001 "SYNCHRONIZE CACHE");
2003 reply = do_synchronize_cache(common);
2006 case TEST_UNIT_READY:
2007 common->data_size_from_cmnd = 0;
2008 reply = check_command(common, 6, DATA_DIR_NONE,
2014 * Although optional, this command is used by MS-Windows. We
2015 * support a minimal version: BytChk must be 0.
2018 common->data_size_from_cmnd = 0;
2019 reply = check_command(common, 10, DATA_DIR_NONE,
2020 (1<<1) | (0xf<<2) | (3<<7), 1,
2023 reply = do_verify(common);
2027 i = common->cmnd[4];
2028 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2029 reply = check_command_size_in_blocks(common, 6,
2034 reply = do_write(common);
2038 common->data_size_from_cmnd =
2039 get_unaligned_be16(&common->cmnd[7]);
2040 reply = check_command_size_in_blocks(common, 10,
2042 (1<<1) | (0xf<<2) | (3<<7), 1,
2045 reply = do_write(common);
2049 common->data_size_from_cmnd =
2050 get_unaligned_be32(&common->cmnd[6]);
2051 reply = check_command_size_in_blocks(common, 12,
2053 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2056 reply = do_write(common);
2060 * Some mandatory commands that we recognize but don't implement.
2061 * They don't mean much in this setting. It's left as an exercise
2062 * for anyone interested to implement RESERVE and RELEASE in terms
2068 case SEND_DIAGNOSTIC:
2073 common->data_size_from_cmnd = 0;
2074 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2075 reply = check_command(common, common->cmnd_size,
2076 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2078 common->curlun->sense_data = SS_INVALID_COMMAND;
2083 up_read(&common->filesem);
2085 if (reply == -EINTR || signal_pending(current))
2088 /* Set up the single reply buffer for finish_reply() */
2089 if (reply == -EINVAL)
2090 reply = 0; /* Error reply length */
2091 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2092 reply = min((u32)reply, common->data_size_from_cmnd);
2093 bh->inreq->length = reply;
2094 bh->state = BUF_STATE_FULL;
2095 common->residue -= reply;
2096 } /* Otherwise it's already set */
2102 /*-------------------------------------------------------------------------*/
2104 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2106 struct usb_request *req = bh->outreq;
2107 struct bulk_cb_wrap *cbw = req->buf;
2108 struct fsg_common *common = fsg->common;
2110 /* Was this a real packet? Should it be ignored? */
2111 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2114 /* Is the CBW valid? */
2115 if (req->actual != US_BULK_CB_WRAP_LEN ||
2116 cbw->Signature != cpu_to_le32(
2118 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2120 le32_to_cpu(cbw->Signature));
2123 * The Bulk-only spec says we MUST stall the IN endpoint
2124 * (6.6.1), so it's unavoidable. It also says we must
2125 * retain this state until the next reset, but there's
2126 * no way to tell the controller driver it should ignore
2127 * Clear-Feature(HALT) requests.
2129 * We aren't required to halt the OUT endpoint; instead
2130 * we can simply accept and discard any data received
2131 * until the next reset.
2133 wedge_bulk_in_endpoint(fsg);
2134 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2138 /* Is the CBW meaningful? */
2139 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2140 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2141 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2143 cbw->Lun, cbw->Flags, cbw->Length);
2146 * We can do anything we want here, so let's stall the
2147 * bulk pipes if we are allowed to.
2149 if (common->can_stall) {
2150 fsg_set_halt(fsg, fsg->bulk_out);
2151 halt_bulk_in_endpoint(fsg);
2156 /* Save the command for later */
2157 common->cmnd_size = cbw->Length;
2158 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2159 if (cbw->Flags & US_BULK_FLAG_IN)
2160 common->data_dir = DATA_DIR_TO_HOST;
2162 common->data_dir = DATA_DIR_FROM_HOST;
2163 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2164 if (common->data_size == 0)
2165 common->data_dir = DATA_DIR_NONE;
2166 common->lun = cbw->Lun;
2167 if (common->lun < common->nluns)
2168 common->curlun = common->luns[common->lun];
2170 common->curlun = NULL;
2171 common->tag = cbw->Tag;
2175 static int get_next_command(struct fsg_common *common)
2177 struct fsg_buffhd *bh;
2180 /* Wait for the next buffer to become available */
2181 bh = common->next_buffhd_to_fill;
2182 while (bh->state != BUF_STATE_EMPTY) {
2183 rc = sleep_thread(common);
2188 /* Queue a request to read a Bulk-only CBW */
2189 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2190 if (!start_out_transfer(common, bh))
2191 /* Don't know what to do if common->fsg is NULL */
2195 * We will drain the buffer in software, which means we
2196 * can reuse it for the next filling. No need to advance
2197 * next_buffhd_to_fill.
2200 /* Wait for the CBW to arrive */
2201 while (bh->state != BUF_STATE_FULL) {
2202 rc = sleep_thread(common);
2207 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2208 bh->state = BUF_STATE_EMPTY;
2214 /*-------------------------------------------------------------------------*/
2216 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2217 struct usb_request **preq)
2219 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2222 ERROR(common, "can't allocate request for %s\n", ep->name);
2226 /* Reset interface setting and re-init endpoint state (toggle etc). */
2227 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2229 struct fsg_dev *fsg;
2232 if (common->running)
2233 DBG(common, "reset interface\n");
2236 /* Deallocate the requests */
2240 for (i = 0; i < common->fsg_num_buffers; ++i) {
2241 struct fsg_buffhd *bh = &common->buffhds[i];
2244 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2248 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2253 /* Disable the endpoints */
2254 if (fsg->bulk_in_enabled) {
2255 usb_ep_disable(fsg->bulk_in);
2256 fsg->bulk_in->driver_data = NULL;
2257 fsg->bulk_in_enabled = 0;
2259 if (fsg->bulk_out_enabled) {
2260 usb_ep_disable(fsg->bulk_out);
2261 fsg->bulk_out->driver_data = NULL;
2262 fsg->bulk_out_enabled = 0;
2266 wake_up(&common->fsg_wait);
2269 common->running = 0;
2273 common->fsg = new_fsg;
2276 /* Enable the endpoints */
2277 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2280 rc = usb_ep_enable(fsg->bulk_in);
2283 fsg->bulk_in->driver_data = common;
2284 fsg->bulk_in_enabled = 1;
2286 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2290 rc = usb_ep_enable(fsg->bulk_out);
2293 fsg->bulk_out->driver_data = common;
2294 fsg->bulk_out_enabled = 1;
2295 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2296 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2298 /* Allocate the requests */
2299 for (i = 0; i < common->fsg_num_buffers; ++i) {
2300 struct fsg_buffhd *bh = &common->buffhds[i];
2302 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2305 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2308 bh->inreq->buf = bh->outreq->buf = bh->buf;
2309 bh->inreq->context = bh->outreq->context = bh;
2310 bh->inreq->complete = bulk_in_complete;
2311 bh->outreq->complete = bulk_out_complete;
2314 common->running = 1;
2315 for (i = 0; i < common->nluns; ++i)
2316 if (common->luns[i])
2317 common->luns[i]->unit_attention_data =
2323 /****************************** ALT CONFIGS ******************************/
2325 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2327 struct fsg_dev *fsg = fsg_from_func(f);
2328 fsg->common->new_fsg = fsg;
2329 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2330 return USB_GADGET_DELAYED_STATUS;
2333 static void fsg_disable(struct usb_function *f)
2335 struct fsg_dev *fsg = fsg_from_func(f);
2336 fsg->common->new_fsg = NULL;
2337 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2341 /*-------------------------------------------------------------------------*/
2343 static void handle_exception(struct fsg_common *common)
2347 struct fsg_buffhd *bh;
2348 enum fsg_state old_state;
2349 struct fsg_lun *curlun;
2350 unsigned int exception_req_tag;
2353 * Clear the existing signals. Anything but SIGUSR1 is converted
2354 * into a high-priority EXIT exception.
2358 dequeue_signal_lock(current, ¤t->blocked, &info);
2361 if (sig != SIGUSR1) {
2362 if (common->state < FSG_STATE_EXIT)
2363 DBG(common, "Main thread exiting on signal\n");
2364 raise_exception(common, FSG_STATE_EXIT);
2368 /* Cancel all the pending transfers */
2369 if (likely(common->fsg)) {
2370 for (i = 0; i < common->fsg_num_buffers; ++i) {
2371 bh = &common->buffhds[i];
2373 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2374 if (bh->outreq_busy)
2375 usb_ep_dequeue(common->fsg->bulk_out,
2379 /* Wait until everything is idle */
2382 for (i = 0; i < common->fsg_num_buffers; ++i) {
2383 bh = &common->buffhds[i];
2384 num_active += bh->inreq_busy + bh->outreq_busy;
2386 if (num_active == 0)
2388 if (sleep_thread(common))
2392 /* Clear out the controller's fifos */
2393 if (common->fsg->bulk_in_enabled)
2394 usb_ep_fifo_flush(common->fsg->bulk_in);
2395 if (common->fsg->bulk_out_enabled)
2396 usb_ep_fifo_flush(common->fsg->bulk_out);
2400 * Reset the I/O buffer states and pointers, the SCSI
2401 * state, and the exception. Then invoke the handler.
2403 spin_lock_irq(&common->lock);
2405 for (i = 0; i < common->fsg_num_buffers; ++i) {
2406 bh = &common->buffhds[i];
2407 bh->state = BUF_STATE_EMPTY;
2409 common->next_buffhd_to_fill = &common->buffhds[0];
2410 common->next_buffhd_to_drain = &common->buffhds[0];
2411 exception_req_tag = common->exception_req_tag;
2412 old_state = common->state;
2414 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2415 common->state = FSG_STATE_STATUS_PHASE;
2417 for (i = 0; i < common->nluns; ++i) {
2418 curlun = common->luns[i];
2421 curlun->prevent_medium_removal = 0;
2422 curlun->sense_data = SS_NO_SENSE;
2423 curlun->unit_attention_data = SS_NO_SENSE;
2424 curlun->sense_data_info = 0;
2425 curlun->info_valid = 0;
2427 common->state = FSG_STATE_IDLE;
2429 spin_unlock_irq(&common->lock);
2431 /* Carry out any extra actions required for the exception */
2432 switch (old_state) {
2433 case FSG_STATE_ABORT_BULK_OUT:
2434 send_status(common);
2435 spin_lock_irq(&common->lock);
2436 if (common->state == FSG_STATE_STATUS_PHASE)
2437 common->state = FSG_STATE_IDLE;
2438 spin_unlock_irq(&common->lock);
2441 case FSG_STATE_RESET:
2443 * In case we were forced against our will to halt a
2444 * bulk endpoint, clear the halt now. (The SuperH UDC
2447 if (!fsg_is_set(common))
2449 if (test_and_clear_bit(IGNORE_BULK_OUT,
2450 &common->fsg->atomic_bitflags))
2451 usb_ep_clear_halt(common->fsg->bulk_in);
2453 if (common->ep0_req_tag == exception_req_tag)
2454 ep0_queue(common); /* Complete the status stage */
2457 * Technically this should go here, but it would only be
2458 * a waste of time. Ditto for the INTERFACE_CHANGE and
2459 * CONFIG_CHANGE cases.
2461 /* for (i = 0; i < common->nluns; ++i) */
2462 /* if (common->luns[i]) */
2463 /* common->luns[i]->unit_attention_data = */
2464 /* SS_RESET_OCCURRED; */
2467 case FSG_STATE_CONFIG_CHANGE:
2468 do_set_interface(common, common->new_fsg);
2469 if (common->new_fsg)
2470 usb_composite_setup_continue(common->cdev);
2473 case FSG_STATE_EXIT:
2474 case FSG_STATE_TERMINATED:
2475 do_set_interface(common, NULL); /* Free resources */
2476 spin_lock_irq(&common->lock);
2477 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2478 spin_unlock_irq(&common->lock);
2481 case FSG_STATE_INTERFACE_CHANGE:
2482 case FSG_STATE_DISCONNECT:
2483 case FSG_STATE_COMMAND_PHASE:
2484 case FSG_STATE_DATA_PHASE:
2485 case FSG_STATE_STATUS_PHASE:
2486 case FSG_STATE_IDLE:
2492 /*-------------------------------------------------------------------------*/
2494 static int fsg_main_thread(void *common_)
2496 struct fsg_common *common = common_;
2499 * Allow the thread to be killed by a signal, but set the signal mask
2500 * to block everything but INT, TERM, KILL, and USR1.
2502 allow_signal(SIGINT);
2503 allow_signal(SIGTERM);
2504 allow_signal(SIGKILL);
2505 allow_signal(SIGUSR1);
2507 /* Allow the thread to be frozen */
2511 * Arrange for userspace references to be interpreted as kernel
2512 * pointers. That way we can pass a kernel pointer to a routine
2513 * that expects a __user pointer and it will work okay.
2518 while (common->state != FSG_STATE_TERMINATED) {
2519 if (exception_in_progress(common) || signal_pending(current)) {
2520 handle_exception(common);
2524 if (!common->running) {
2525 sleep_thread(common);
2529 if (get_next_command(common))
2532 spin_lock_irq(&common->lock);
2533 if (!exception_in_progress(common))
2534 common->state = FSG_STATE_DATA_PHASE;
2535 spin_unlock_irq(&common->lock);
2537 if (do_scsi_command(common) || finish_reply(common))
2540 spin_lock_irq(&common->lock);
2541 if (!exception_in_progress(common))
2542 common->state = FSG_STATE_STATUS_PHASE;
2543 spin_unlock_irq(&common->lock);
2545 if (send_status(common))
2548 spin_lock_irq(&common->lock);
2549 if (!exception_in_progress(common))
2550 common->state = FSG_STATE_IDLE;
2551 spin_unlock_irq(&common->lock);
2554 spin_lock_irq(&common->lock);
2555 common->thread_task = NULL;
2556 spin_unlock_irq(&common->lock);
2558 if (!common->ops || !common->ops->thread_exits
2559 || common->ops->thread_exits(common) < 0) {
2560 struct fsg_lun **curlun_it = common->luns;
2561 unsigned i = common->nluns;
2563 down_write(&common->filesem);
2564 for (; i--; ++curlun_it) {
2565 struct fsg_lun *curlun = *curlun_it;
2566 if (!curlun || !fsg_lun_is_open(curlun))
2569 fsg_lun_close(curlun);
2570 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2572 up_write(&common->filesem);
2575 /* Let fsg_unbind() know the thread has exited */
2576 complete_and_exit(&common->thread_notifier, 0);
2580 /*************************** DEVICE ATTRIBUTES ***************************/
2582 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2584 return fsg_show_ro(dev, attr, buf);
2587 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2590 return fsg_show_nofua(dev, attr, buf);
2593 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2596 return fsg_show_file(dev, attr, buf);
2599 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2600 const char *buf, size_t count)
2602 return fsg_store_ro(dev, attr, buf, count);
2605 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2606 const char *buf, size_t count)
2608 return fsg_store_nofua(dev, attr, buf, count);
2611 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2612 const char *buf, size_t count)
2614 return fsg_store_file(dev, attr, buf, count);
2617 static DEVICE_ATTR_RW(ro);
2618 static DEVICE_ATTR_RW(nofua);
2619 static DEVICE_ATTR_RW(file);
2621 static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro);
2622 static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file);
2625 /****************************** FSG COMMON ******************************/
2627 static void fsg_common_release(struct kref *ref);
2629 static void fsg_lun_release(struct device *dev)
2631 /* Nothing needs to be done */
2634 void fsg_common_get(struct fsg_common *common)
2636 kref_get(&common->ref);
2638 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_get);
2640 void fsg_common_put(struct fsg_common *common)
2642 kref_put(&common->ref, fsg_common_release);
2644 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_put);
2646 /* check if fsg_num_buffers is within a valid range */
2647 static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
2649 if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
2651 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
2652 fsg_num_buffers, 2, 4);
2656 static struct fsg_common *fsg_common_setup(struct fsg_common *common, bool zero)
2659 common = kzalloc(sizeof(*common), GFP_KERNEL);
2661 return ERR_PTR(-ENOMEM);
2662 common->free_storage_on_release = 1;
2665 memset(common, 0, sizeof(*common));
2666 common->free_storage_on_release = 0;
2668 init_rwsem(&common->filesem);
2669 spin_lock_init(&common->lock);
2670 kref_init(&common->ref);
2671 init_completion(&common->thread_notifier);
2672 init_waitqueue_head(&common->fsg_wait);
2673 common->state = FSG_STATE_TERMINATED;
2678 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs)
2680 common->sysfs = sysfs;
2682 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_set_sysfs);
2684 static void _fsg_common_free_buffers(struct fsg_buffhd *buffhds, unsigned n)
2687 struct fsg_buffhd *bh = buffhds;
2696 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n)
2698 struct fsg_buffhd *bh, *buffhds;
2701 rc = fsg_num_buffers_validate(n);
2705 buffhds = kcalloc(n, sizeof(*buffhds), GFP_KERNEL);
2709 /* Data buffers cyclic list */
2712 goto buffhds_first_it;
2717 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2718 if (unlikely(!bh->buf))
2723 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2724 common->fsg_num_buffers = n;
2725 common->buffhds = buffhds;
2731 * "buf"s pointed to by heads after n - i are NULL
2732 * so releasing them won't hurt
2734 _fsg_common_free_buffers(buffhds, n);
2738 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_set_num_buffers);
2740 static inline void fsg_common_remove_sysfs(struct fsg_lun *lun)
2742 device_remove_file(&lun->dev, &dev_attr_nofua);
2744 * device_remove_file() =>
2746 * here the attr (e.g. dev_attr_ro) is only used to be passed to:
2748 * sysfs_remove_file() =>
2750 * here e.g. both dev_attr_ro_cdrom and dev_attr_ro are in
2751 * the same namespace and
2752 * from here only attr->name is passed to:
2754 * sysfs_hash_and_remove()
2756 * attr->name is the same for dev_attr_ro_cdrom and
2758 * attr->name is the same for dev_attr_file and
2759 * dev_attr_file_nonremovable
2761 * so we don't differentiate between removing e.g. dev_attr_ro_cdrom
2764 device_remove_file(&lun->dev, &dev_attr_ro);
2765 device_remove_file(&lun->dev, &dev_attr_file);
2768 void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs)
2771 fsg_common_remove_sysfs(lun);
2772 device_unregister(&lun->dev);
2777 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_remove_lun);
2779 static void _fsg_common_remove_luns(struct fsg_common *common, int n)
2783 for (i = 0; i < n; ++i)
2784 if (common->luns[i]) {
2785 fsg_common_remove_lun(common->luns[i], common->sysfs);
2786 common->luns[i] = NULL;
2789 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_remove_luns);
2791 void fsg_common_remove_luns(struct fsg_common *common)
2793 _fsg_common_remove_luns(common, common->nluns);
2796 void fsg_common_free_luns(struct fsg_common *common)
2798 fsg_common_remove_luns(common);
2799 kfree(common->luns);
2800 common->luns = NULL;
2802 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_free_luns);
2804 int fsg_common_set_nluns(struct fsg_common *common, int nluns)
2806 struct fsg_lun **curlun;
2808 /* Find out how many LUNs there should be */
2809 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2810 pr_err("invalid number of LUNs: %u\n", nluns);
2814 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2815 if (unlikely(!curlun))
2819 fsg_common_free_luns(common);
2821 common->luns = curlun;
2822 common->nluns = nluns;
2824 pr_info("Number of LUNs=%d\n", common->nluns);
2828 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_set_nluns);
2830 void fsg_common_free_buffers(struct fsg_common *common)
2832 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
2833 common->buffhds = NULL;
2835 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_free_buffers);
2837 int fsg_common_set_cdev(struct fsg_common *common,
2838 struct usb_composite_dev *cdev, bool can_stall)
2840 struct usb_string *us;
2842 common->gadget = cdev->gadget;
2843 common->ep0 = cdev->gadget->ep0;
2844 common->ep0req = cdev->req;
2845 common->cdev = cdev;
2847 us = usb_gstrings_attach(cdev, fsg_strings_array,
2848 ARRAY_SIZE(fsg_strings));
2852 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2855 * Some peripheral controllers are known not to be able to
2856 * halt bulk endpoints correctly. If one of them is present,
2859 common->can_stall = can_stall && !(gadget_is_at91(common->gadget));
2863 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_set_cdev);
2865 static inline int fsg_common_add_sysfs(struct fsg_common *common,
2866 struct fsg_lun *lun)
2870 rc = device_register(&lun->dev);
2872 put_device(&lun->dev);
2876 rc = device_create_file(&lun->dev,
2878 ? &dev_attr_ro_cdrom
2882 rc = device_create_file(&lun->dev,
2885 : &dev_attr_file_nonremovable);
2888 rc = device_create_file(&lun->dev, &dev_attr_nofua);
2895 /* removing nonexistent files is a no-op */
2896 fsg_common_remove_sysfs(lun);
2897 device_unregister(&lun->dev);
2901 int fsg_common_create_lun(struct fsg_common *common, struct fsg_lun_config *cfg,
2902 unsigned int id, const char *name,
2903 const char **name_pfx)
2905 struct fsg_lun *lun;
2909 if (!common->nluns || !common->luns)
2912 if (common->luns[id])
2915 if (!cfg->filename && !cfg->removable) {
2916 pr_err("no file given for LUN%d\n", id);
2920 lun = kzalloc(sizeof(*lun), GFP_KERNEL);
2924 lun->name_pfx = name_pfx;
2926 lun->cdrom = !!cfg->cdrom;
2927 lun->ro = cfg->cdrom || cfg->ro;
2928 lun->initially_ro = lun->ro;
2929 lun->removable = !!cfg->removable;
2931 if (!common->sysfs) {
2932 /* we DON'T own the name!*/
2935 lun->dev.release = fsg_lun_release;
2936 lun->dev.parent = &common->gadget->dev;
2937 dev_set_drvdata(&lun->dev, &common->filesem);
2938 dev_set_name(&lun->dev, name);
2939 lun->name = dev_name(&lun->dev);
2941 rc = fsg_common_add_sysfs(common, lun);
2943 pr_info("failed to register LUN%d: %d\n", id, rc);
2948 common->luns[id] = lun;
2950 if (cfg->filename) {
2951 rc = fsg_lun_open(lun, cfg->filename);
2956 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2958 if (fsg_lun_is_open(lun)) {
2961 p = d_path(&lun->filp->f_path, pathbuf, PATH_MAX);
2966 pr_info("LUN: %s%s%sfile: %s\n",
2967 lun->removable ? "removable " : "",
2968 lun->ro ? "read only " : "",
2969 lun->cdrom ? "CD-ROM " : "",
2976 if (common->sysfs) {
2977 fsg_common_remove_sysfs(lun);
2978 device_unregister(&lun->dev);
2981 common->luns[id] = NULL;
2986 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_create_lun);
2988 int fsg_common_create_luns(struct fsg_common *common, struct fsg_config *cfg)
2990 char buf[8]; /* enough for 100000000 different numbers, decimal */
2993 for (i = 0; i < common->nluns; ++i) {
2994 snprintf(buf, sizeof(buf), "lun%d", i);
2995 rc = fsg_common_create_lun(common, &cfg->luns[i], i, buf, NULL);
3000 pr_info("Number of LUNs=%d\n", common->nluns);
3005 _fsg_common_remove_luns(common, i);
3008 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_create_luns);
3010 void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
3015 /* Prepare inquiryString */
3016 i = get_default_bcdDevice();
3017 snprintf(common->inquiry_string, sizeof(common->inquiry_string),
3018 "%-8s%-16s%04x", vn ?: "Linux",
3019 /* Assume product name dependent on the first LUN */
3020 pn ?: ((*common->luns)->cdrom
3022 : "File-Stor Gadget"),
3025 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_set_inquiry_string);
3027 int fsg_common_run_thread(struct fsg_common *common)
3029 common->state = FSG_STATE_IDLE;
3030 /* Tell the thread to start working */
3031 common->thread_task =
3032 kthread_create(fsg_main_thread, common, "file-storage");
3033 if (IS_ERR(common->thread_task)) {
3034 common->state = FSG_STATE_TERMINATED;
3035 return PTR_ERR(common->thread_task);
3038 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
3040 wake_up_process(common->thread_task);
3044 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_run_thread);
3046 struct fsg_common *fsg_common_init(struct fsg_common *common,
3047 struct usb_composite_dev *cdev,
3048 struct fsg_config *cfg)
3052 common = fsg_common_setup(common, !!common);
3055 fsg_common_set_sysfs(common, true);
3056 common->state = FSG_STATE_IDLE;
3058 rc = fsg_common_set_num_buffers(common, cfg->fsg_num_buffers);
3060 if (common->free_storage_on_release)
3064 common->ops = cfg->ops;
3065 common->private_data = cfg->private_data;
3067 rc = fsg_common_set_cdev(common, cdev, cfg->can_stall);
3071 rc = fsg_common_set_nluns(common, cfg->nluns);
3075 rc = fsg_common_create_luns(common, cfg);
3080 fsg_common_set_inquiry_string(common, cfg->vendor_name,
3084 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3086 rc = fsg_common_run_thread(common);
3093 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
3094 /* Call fsg_common_release() directly, ref might be not initialised. */
3095 fsg_common_release(&common->ref);
3098 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_common_init);
3100 static void fsg_common_release(struct kref *ref)
3102 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
3104 /* If the thread isn't already dead, tell it to exit now */
3105 if (common->state != FSG_STATE_TERMINATED) {
3106 raise_exception(common, FSG_STATE_EXIT);
3107 wait_for_completion(&common->thread_notifier);
3110 if (likely(common->luns)) {
3111 struct fsg_lun **lun_it = common->luns;
3112 unsigned i = common->nluns;
3114 /* In error recovery common->nluns may be zero. */
3115 for (; i; --i, ++lun_it) {
3116 struct fsg_lun *lun = *lun_it;
3120 fsg_common_remove_sysfs(lun);
3123 device_unregister(&lun->dev);
3127 kfree(common->luns);
3130 _fsg_common_free_buffers(common->buffhds, common->fsg_num_buffers);
3131 if (common->free_storage_on_release)
3136 /*-------------------------------------------------------------------------*/
3138 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
3140 struct fsg_dev *fsg = fsg_from_func(f);
3141 struct usb_gadget *gadget = c->cdev->gadget;
3147 #ifndef USB_FMS_INCLUDED
3148 struct fsg_opts *opts;
3149 opts = fsg_opts_from_func_inst(f->fi);
3150 if (!opts->no_configfs) {
3151 ret = fsg_common_set_cdev(fsg->common, c->cdev,
3152 fsg->common->can_stall);
3155 fsg_common_set_inquiry_string(fsg->common, 0, 0);
3156 ret = fsg_common_run_thread(fsg->common);
3162 fsg->gadget = gadget;
3165 i = usb_interface_id(c, f);
3168 fsg_intf_desc.bInterfaceNumber = i;
3169 fsg->interface_number = i;
3171 /* Find all the endpoints we will use */
3172 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
3175 ep->driver_data = fsg->common; /* claim the endpoint */
3178 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
3181 ep->driver_data = fsg->common; /* claim the endpoint */
3184 /* Assume endpoint addresses are the same for both speeds */
3185 fsg_hs_bulk_in_desc.bEndpointAddress =
3186 fsg_fs_bulk_in_desc.bEndpointAddress;
3187 fsg_hs_bulk_out_desc.bEndpointAddress =
3188 fsg_fs_bulk_out_desc.bEndpointAddress;
3190 /* Calculate bMaxBurst, we know packet size is 1024 */
3191 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
3193 fsg_ss_bulk_in_desc.bEndpointAddress =
3194 fsg_fs_bulk_in_desc.bEndpointAddress;
3195 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
3197 fsg_ss_bulk_out_desc.bEndpointAddress =
3198 fsg_fs_bulk_out_desc.bEndpointAddress;
3199 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
3201 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
3209 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3213 /****************************** ALLOCATE FUNCTION *************************/
3215 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
3217 struct fsg_dev *fsg = fsg_from_func(f);
3218 struct fsg_common *common = fsg->common;
3220 DBG(fsg, "unbind\n");
3221 if (fsg->common->fsg == fsg) {
3222 fsg->common->new_fsg = NULL;
3223 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
3224 /* FIXME: make interruptible or killable somehow? */
3225 wait_event(common->fsg_wait, common->fsg != fsg);
3228 #ifdef USB_FMS_INCLUDED
3229 fsg_common_put(common);
3231 usb_free_all_descriptors(&fsg->function);
3232 #ifdef USB_FMS_INCLUDED
3237 #ifdef USB_FMS_INCLUDED
3239 static int fsg_bind_config(struct usb_composite_dev *cdev,
3240 struct usb_configuration *c,
3241 struct fsg_common *common)
3243 struct fsg_dev *fsg;
3246 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3250 fsg->function.name = FSG_DRIVER_DESC;
3251 fsg->function.bind = fsg_bind;
3252 fsg->function.unbind = fsg_unbind;
3253 fsg->function.setup = fsg_setup;
3254 fsg->function.set_alt = fsg_set_alt;
3255 fsg->function.disable = fsg_disable;
3257 fsg->common = common;
3259 * Our caller holds a reference to common structure so we
3260 * don't have to be worry about it being freed until we return
3261 * from this function. So instead of incrementing counter now
3262 * and decrement in error recovery we increment it only when
3263 * call to usb_add_function() was successful.
3266 rc = usb_add_function(c, &fsg->function);
3270 fsg_common_get(fsg->common);
3276 static void fsg_free_inst(struct usb_function_instance *fi)
3278 struct fsg_opts *opts;
3280 opts = fsg_opts_from_func_inst(fi);
3281 fsg_common_put(opts->common);
3285 static struct usb_function_instance *fsg_alloc_inst(void)
3287 struct fsg_opts *opts;
3290 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
3292 return ERR_PTR(-ENOMEM);
3293 opts->func_inst.free_func_inst = fsg_free_inst;
3294 opts->common = fsg_common_setup(opts->common, false);
3295 if (IS_ERR(opts->common)) {
3296 rc = PTR_ERR(opts->common);
3299 rc = fsg_common_set_nluns(opts->common, FSG_MAX_LUNS);
3303 rc = fsg_common_set_num_buffers(opts->common,
3304 CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
3308 pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
3310 return &opts->func_inst;
3313 kfree(opts->common->luns);
3319 static void fsg_free(struct usb_function *f)
3321 struct fsg_dev *fsg;
3323 fsg = container_of(f, struct fsg_dev, function);
3328 static struct usb_function *fsg_alloc(struct usb_function_instance *fi)
3330 struct fsg_opts *opts = fsg_opts_from_func_inst(fi);
3331 struct fsg_common *common = opts->common;
3332 struct fsg_dev *fsg;
3334 fsg = kzalloc(sizeof(*fsg), GFP_KERNEL);
3336 return ERR_PTR(-ENOMEM);
3338 fsg->function.name = FSG_DRIVER_DESC;
3339 fsg->function.bind = fsg_bind;
3340 fsg->function.unbind = fsg_unbind;
3341 fsg->function.setup = fsg_setup;
3342 fsg->function.set_alt = fsg_set_alt;
3343 fsg->function.disable = fsg_disable;
3344 fsg->function.free_func = fsg_free;
3346 fsg->common = common;
3348 return &fsg->function;
3351 DECLARE_USB_FUNCTION_INIT(mass_storage, fsg_alloc_inst, fsg_alloc);
3352 MODULE_LICENSE("GPL");
3353 MODULE_AUTHOR("Michal Nazarewicz");
3357 /************************* Module parameters *************************/
3360 void fsg_config_from_params(struct fsg_config *cfg,
3361 const struct fsg_module_parameters *params,
3362 unsigned int fsg_num_buffers)
3364 struct fsg_lun_config *lun;
3367 /* Configure LUNs */
3369 min(params->luns ?: (params->file_count ?: 1u),
3370 (unsigned)FSG_MAX_LUNS);
3371 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3372 lun->ro = !!params->ro[i];
3373 lun->cdrom = !!params->cdrom[i];
3374 lun->removable = !!params->removable[i];
3376 params->file_count > i && params->file[i][0]
3381 /* Let MSF use defaults */
3382 cfg->vendor_name = NULL;
3383 cfg->product_name = NULL;
3386 cfg->private_data = NULL;
3389 cfg->can_stall = params->stall;
3390 cfg->fsg_num_buffers = fsg_num_buffers;
3392 EXPORT_SYMBOL_GPL_IF_MODULE(fsg_config_from_params);