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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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
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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>
217 #include <linux/usb/ch9.h>
218 #include <linux/usb/gadget.h>
219 #include <linux/usb/composite.h>
221 #include "gadget_chips.h"
224 /*------------------------------------------------------------------------*/
226 #define FSG_DRIVER_DESC "Mass Storage Function"
227 #define FSG_DRIVER_VERSION "2009/09/11"
229 static const char fsg_string_interface[] = "Mass Storage";
231 #include "storage_common.h"
232 #include "f_mass_storage.h"
234 /* Static strings, in UTF-8 (for simplicity we use only ASCII characters) */
235 static struct usb_string fsg_strings[] = {
236 {FSG_STRING_INTERFACE, fsg_string_interface},
240 static struct usb_gadget_strings fsg_stringtab = {
241 .language = 0x0409, /* en-us */
242 .strings = fsg_strings,
245 static struct usb_gadget_strings *fsg_strings_array[] = {
250 /*-------------------------------------------------------------------------*/
255 /* Data shared by all the FSG instances. */
257 struct usb_gadget *gadget;
258 struct usb_composite_dev *cdev;
259 struct fsg_dev *fsg, *new_fsg;
260 wait_queue_head_t fsg_wait;
262 /* filesem protects: backing files in use */
263 struct rw_semaphore filesem;
265 /* lock protects: state, all the req_busy's */
268 struct usb_ep *ep0; /* Copy of gadget->ep0 */
269 struct usb_request *ep0req; /* Copy of cdev->req */
270 unsigned int ep0_req_tag;
272 struct fsg_buffhd *next_buffhd_to_fill;
273 struct fsg_buffhd *next_buffhd_to_drain;
274 struct fsg_buffhd *buffhds;
275 unsigned int fsg_num_buffers;
278 u8 cmnd[MAX_COMMAND_SIZE];
282 struct fsg_lun **luns;
283 struct fsg_lun *curlun;
285 unsigned int bulk_out_maxpacket;
286 enum fsg_state state; /* For exception handling */
287 unsigned int exception_req_tag;
289 enum data_direction data_dir;
291 u32 data_size_from_cmnd;
296 unsigned int can_stall:1;
297 unsigned int free_storage_on_release:1;
298 unsigned int phase_error:1;
299 unsigned int short_packet_received:1;
300 unsigned int bad_lun_okay:1;
301 unsigned int running:1;
303 int thread_wakeup_needed;
304 struct completion thread_notifier;
305 struct task_struct *thread_task;
307 /* Callback functions. */
308 const struct fsg_operations *ops;
309 /* Gadget's private data. */
313 * Vendor (8 chars), product (16 chars), release (4
314 * hexadecimal digits) and NUL byte
316 char inquiry_string[8 + 16 + 4 + 1];
322 struct usb_function function;
323 struct usb_gadget *gadget; /* Copy of cdev->gadget */
324 struct fsg_common *common;
326 u16 interface_number;
328 unsigned int bulk_in_enabled:1;
329 unsigned int bulk_out_enabled:1;
331 unsigned long atomic_bitflags;
332 #define IGNORE_BULK_OUT 0
334 struct usb_ep *bulk_in;
335 struct usb_ep *bulk_out;
338 static inline int __fsg_is_set(struct fsg_common *common,
339 const char *func, unsigned line)
343 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
348 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
350 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
352 return container_of(f, struct fsg_dev, function);
355 typedef void (*fsg_routine_t)(struct fsg_dev *);
357 static int exception_in_progress(struct fsg_common *common)
359 return common->state > FSG_STATE_IDLE;
362 /* Make bulk-out requests be divisible by the maxpacket size */
363 static void set_bulk_out_req_length(struct fsg_common *common,
364 struct fsg_buffhd *bh, unsigned int length)
368 bh->bulk_out_intended_length = length;
369 rem = length % common->bulk_out_maxpacket;
371 length += common->bulk_out_maxpacket - rem;
372 bh->outreq->length = length;
376 /*-------------------------------------------------------------------------*/
378 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
382 if (ep == fsg->bulk_in)
384 else if (ep == fsg->bulk_out)
388 DBG(fsg, "%s set halt\n", name);
389 return usb_ep_set_halt(ep);
393 /*-------------------------------------------------------------------------*/
395 /* These routines may be called in process context or in_irq */
397 /* Caller must hold fsg->lock */
398 static void wakeup_thread(struct fsg_common *common)
400 smp_wmb(); /* ensure the write of bh->state is complete */
401 /* Tell the main thread that something has happened */
402 common->thread_wakeup_needed = 1;
403 if (common->thread_task)
404 wake_up_process(common->thread_task);
407 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
412 * Do nothing if a higher-priority exception is already in progress.
413 * If a lower-or-equal priority exception is in progress, preempt it
414 * and notify the main thread by sending it a signal.
416 spin_lock_irqsave(&common->lock, flags);
417 if (common->state <= new_state) {
418 common->exception_req_tag = common->ep0_req_tag;
419 common->state = new_state;
420 if (common->thread_task)
421 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
422 common->thread_task);
424 spin_unlock_irqrestore(&common->lock, flags);
428 /*-------------------------------------------------------------------------*/
430 static int ep0_queue(struct fsg_common *common)
434 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
435 common->ep0->driver_data = common;
436 if (rc != 0 && rc != -ESHUTDOWN) {
437 /* We can't do much more than wait for a reset */
438 WARNING(common, "error in submission: %s --> %d\n",
439 common->ep0->name, rc);
445 /*-------------------------------------------------------------------------*/
447 /* Completion handlers. These always run in_irq. */
449 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
451 struct fsg_common *common = ep->driver_data;
452 struct fsg_buffhd *bh = req->context;
454 if (req->status || req->actual != req->length)
455 DBG(common, "%s --> %d, %u/%u\n", __func__,
456 req->status, req->actual, req->length);
457 if (req->status == -ECONNRESET) /* Request was cancelled */
458 usb_ep_fifo_flush(ep);
460 /* Hold the lock while we update the request and buffer states */
462 spin_lock(&common->lock);
464 bh->state = BUF_STATE_EMPTY;
465 wakeup_thread(common);
466 spin_unlock(&common->lock);
469 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
471 struct fsg_common *common = ep->driver_data;
472 struct fsg_buffhd *bh = req->context;
474 dump_msg(common, "bulk-out", req->buf, req->actual);
475 if (req->status || req->actual != bh->bulk_out_intended_length)
476 DBG(common, "%s --> %d, %u/%u\n", __func__,
477 req->status, req->actual, bh->bulk_out_intended_length);
478 if (req->status == -ECONNRESET) /* Request was cancelled */
479 usb_ep_fifo_flush(ep);
481 /* Hold the lock while we update the request and buffer states */
483 spin_lock(&common->lock);
485 bh->state = BUF_STATE_FULL;
486 wakeup_thread(common);
487 spin_unlock(&common->lock);
490 static int fsg_setup(struct usb_function *f,
491 const struct usb_ctrlrequest *ctrl)
493 struct fsg_dev *fsg = fsg_from_func(f);
494 struct usb_request *req = fsg->common->ep0req;
495 u16 w_index = le16_to_cpu(ctrl->wIndex);
496 u16 w_value = le16_to_cpu(ctrl->wValue);
497 u16 w_length = le16_to_cpu(ctrl->wLength);
499 if (!fsg_is_set(fsg->common))
502 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
505 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
507 switch (ctrl->bRequest) {
509 case US_BULK_RESET_REQUEST:
510 if (ctrl->bRequestType !=
511 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
513 if (w_index != fsg->interface_number || w_value != 0 ||
518 * Raise an exception to stop the current operation
519 * and reinitialize our state.
521 DBG(fsg, "bulk reset request\n");
522 raise_exception(fsg->common, FSG_STATE_RESET);
523 return DELAYED_STATUS;
525 case US_BULK_GET_MAX_LUN:
526 if (ctrl->bRequestType !=
527 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
529 if (w_index != fsg->interface_number || w_value != 0 ||
532 VDBG(fsg, "get max LUN\n");
533 *(u8 *)req->buf = fsg->common->nluns - 1;
535 /* Respond with data/status */
536 req->length = min((u16)1, w_length);
537 return ep0_queue(fsg->common);
541 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
542 ctrl->bRequestType, ctrl->bRequest,
543 le16_to_cpu(ctrl->wValue), w_index, w_length);
548 /*-------------------------------------------------------------------------*/
550 /* All the following routines run in process context */
552 /* Use this for bulk or interrupt transfers, not ep0 */
553 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
554 struct usb_request *req, int *pbusy,
555 enum fsg_buffer_state *state)
559 if (ep == fsg->bulk_in)
560 dump_msg(fsg, "bulk-in", req->buf, req->length);
562 spin_lock_irq(&fsg->common->lock);
564 *state = BUF_STATE_BUSY;
565 spin_unlock_irq(&fsg->common->lock);
566 rc = usb_ep_queue(ep, req, GFP_KERNEL);
569 *state = BUF_STATE_EMPTY;
571 /* We can't do much more than wait for a reset */
574 * Note: currently the net2280 driver fails zero-length
575 * submissions if DMA is enabled.
577 if (rc != -ESHUTDOWN &&
578 !(rc == -EOPNOTSUPP && req->length == 0))
579 WARNING(fsg, "error in submission: %s --> %d\n",
584 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
586 if (!fsg_is_set(common))
588 start_transfer(common->fsg, common->fsg->bulk_in,
589 bh->inreq, &bh->inreq_busy, &bh->state);
593 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
595 if (!fsg_is_set(common))
597 start_transfer(common->fsg, common->fsg->bulk_out,
598 bh->outreq, &bh->outreq_busy, &bh->state);
602 static int sleep_thread(struct fsg_common *common)
606 /* Wait until a signal arrives or we are woken up */
609 set_current_state(TASK_INTERRUPTIBLE);
610 if (signal_pending(current)) {
614 if (common->thread_wakeup_needed)
618 __set_current_state(TASK_RUNNING);
619 common->thread_wakeup_needed = 0;
620 smp_rmb(); /* ensure the latest bh->state is visible */
625 /*-------------------------------------------------------------------------*/
627 static int do_read(struct fsg_common *common)
629 struct fsg_lun *curlun = common->curlun;
631 struct fsg_buffhd *bh;
634 loff_t file_offset, file_offset_tmp;
639 * Get the starting Logical Block Address and check that it's
642 if (common->cmnd[0] == READ_6)
643 lba = get_unaligned_be24(&common->cmnd[1]);
645 lba = get_unaligned_be32(&common->cmnd[2]);
648 * We allow DPO (Disable Page Out = don't save data in the
649 * cache) and FUA (Force Unit Access = don't read from the
650 * cache), but we don't implement them.
652 if ((common->cmnd[1] & ~0x18) != 0) {
653 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
657 if (lba >= curlun->num_sectors) {
658 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
661 file_offset = ((loff_t) lba) << curlun->blkbits;
663 /* Carry out the file reads */
664 amount_left = common->data_size_from_cmnd;
665 if (unlikely(amount_left == 0))
666 return -EIO; /* No default reply */
670 * Figure out how much we need to read:
671 * Try to read the remaining amount.
672 * But don't read more than the buffer size.
673 * And don't try to read past the end of the file.
675 amount = min(amount_left, FSG_BUFLEN);
676 amount = min((loff_t)amount,
677 curlun->file_length - file_offset);
679 /* Wait for the next buffer to become available */
680 bh = common->next_buffhd_to_fill;
681 while (bh->state != BUF_STATE_EMPTY) {
682 rc = sleep_thread(common);
688 * If we were asked to read past the end of file,
689 * end with an empty buffer.
693 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
694 curlun->sense_data_info =
695 file_offset >> curlun->blkbits;
696 curlun->info_valid = 1;
697 bh->inreq->length = 0;
698 bh->state = BUF_STATE_FULL;
702 /* Perform the read */
703 file_offset_tmp = file_offset;
704 nread = vfs_read(curlun->filp,
705 (char __user *)bh->buf,
706 amount, &file_offset_tmp);
707 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
708 (unsigned long long)file_offset, (int)nread);
709 if (signal_pending(current))
713 LDBG(curlun, "error in file read: %d\n", (int)nread);
715 } else if (nread < amount) {
716 LDBG(curlun, "partial file read: %d/%u\n",
718 nread = round_down(nread, curlun->blksize);
720 file_offset += nread;
721 amount_left -= nread;
722 common->residue -= nread;
725 * Except at the end of the transfer, nread will be
726 * equal to the buffer size, which is divisible by the
727 * bulk-in maxpacket size.
729 bh->inreq->length = nread;
730 bh->state = BUF_STATE_FULL;
732 /* If an error occurred, report it and its position */
733 if (nread < amount) {
734 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
735 curlun->sense_data_info =
736 file_offset >> curlun->blkbits;
737 curlun->info_valid = 1;
741 if (amount_left == 0)
742 break; /* No more left to read */
744 /* Send this buffer and go read some more */
746 if (!start_in_transfer(common, bh))
747 /* Don't know what to do if common->fsg is NULL */
749 common->next_buffhd_to_fill = bh->next;
752 return -EIO; /* No default reply */
756 /*-------------------------------------------------------------------------*/
758 static int do_write(struct fsg_common *common)
760 struct fsg_lun *curlun = common->curlun;
762 struct fsg_buffhd *bh;
764 u32 amount_left_to_req, amount_left_to_write;
765 loff_t usb_offset, file_offset, file_offset_tmp;
771 curlun->sense_data = SS_WRITE_PROTECTED;
774 spin_lock(&curlun->filp->f_lock);
775 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
776 spin_unlock(&curlun->filp->f_lock);
779 * Get the starting Logical Block Address and check that it's
782 if (common->cmnd[0] == WRITE_6)
783 lba = get_unaligned_be24(&common->cmnd[1]);
785 lba = get_unaligned_be32(&common->cmnd[2]);
788 * We allow DPO (Disable Page Out = don't save data in the
789 * cache) and FUA (Force Unit Access = write directly to the
790 * medium). We don't implement DPO; we implement FUA by
791 * performing synchronous output.
793 if (common->cmnd[1] & ~0x18) {
794 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
797 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
798 spin_lock(&curlun->filp->f_lock);
799 curlun->filp->f_flags |= O_SYNC;
800 spin_unlock(&curlun->filp->f_lock);
803 if (lba >= curlun->num_sectors) {
804 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
808 /* Carry out the file writes */
810 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
811 amount_left_to_req = common->data_size_from_cmnd;
812 amount_left_to_write = common->data_size_from_cmnd;
814 while (amount_left_to_write > 0) {
816 /* Queue a request for more data from the host */
817 bh = common->next_buffhd_to_fill;
818 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
821 * Figure out how much we want to get:
822 * Try to get the remaining amount,
823 * but not more than the buffer size.
825 amount = min(amount_left_to_req, FSG_BUFLEN);
827 /* Beyond the end of the backing file? */
828 if (usb_offset >= curlun->file_length) {
831 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
832 curlun->sense_data_info =
833 usb_offset >> curlun->blkbits;
834 curlun->info_valid = 1;
838 /* Get the next buffer */
839 usb_offset += amount;
840 common->usb_amount_left -= amount;
841 amount_left_to_req -= amount;
842 if (amount_left_to_req == 0)
846 * Except at the end of the transfer, amount will be
847 * equal to the buffer size, which is divisible by
848 * the bulk-out maxpacket size.
850 set_bulk_out_req_length(common, bh, amount);
851 if (!start_out_transfer(common, bh))
852 /* Dunno what to do if common->fsg is NULL */
854 common->next_buffhd_to_fill = bh->next;
858 /* Write the received data to the backing file */
859 bh = common->next_buffhd_to_drain;
860 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
861 break; /* We stopped early */
862 if (bh->state == BUF_STATE_FULL) {
864 common->next_buffhd_to_drain = bh->next;
865 bh->state = BUF_STATE_EMPTY;
867 /* Did something go wrong with the transfer? */
868 if (bh->outreq->status != 0) {
869 curlun->sense_data = SS_COMMUNICATION_FAILURE;
870 curlun->sense_data_info =
871 file_offset >> curlun->blkbits;
872 curlun->info_valid = 1;
876 amount = bh->outreq->actual;
877 if (curlun->file_length - file_offset < amount) {
879 "write %u @ %llu beyond end %llu\n",
880 amount, (unsigned long long)file_offset,
881 (unsigned long long)curlun->file_length);
882 amount = curlun->file_length - file_offset;
885 /* Don't accept excess data. The spec doesn't say
886 * what to do in this case. We'll ignore the error.
888 amount = min(amount, bh->bulk_out_intended_length);
890 /* Don't write a partial block */
891 amount = round_down(amount, curlun->blksize);
895 /* Perform the write */
896 file_offset_tmp = file_offset;
897 nwritten = vfs_write(curlun->filp,
898 (char __user *)bh->buf,
899 amount, &file_offset_tmp);
900 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
901 (unsigned long long)file_offset, (int)nwritten);
902 if (signal_pending(current))
903 return -EINTR; /* Interrupted! */
906 LDBG(curlun, "error in file write: %d\n",
909 } else if (nwritten < amount) {
910 LDBG(curlun, "partial file write: %d/%u\n",
911 (int)nwritten, amount);
912 nwritten = round_down(nwritten, curlun->blksize);
914 file_offset += nwritten;
915 amount_left_to_write -= nwritten;
916 common->residue -= nwritten;
918 /* If an error occurred, report it and its position */
919 if (nwritten < amount) {
920 curlun->sense_data = SS_WRITE_ERROR;
921 curlun->sense_data_info =
922 file_offset >> curlun->blkbits;
923 curlun->info_valid = 1;
928 /* Did the host decide to stop early? */
929 if (bh->outreq->actual < bh->bulk_out_intended_length) {
930 common->short_packet_received = 1;
936 /* Wait for something to happen */
937 rc = sleep_thread(common);
942 return -EIO; /* No default reply */
946 /*-------------------------------------------------------------------------*/
948 static int do_synchronize_cache(struct fsg_common *common)
950 struct fsg_lun *curlun = common->curlun;
953 /* We ignore the requested LBA and write out all file's
954 * dirty data buffers. */
955 rc = fsg_lun_fsync_sub(curlun);
957 curlun->sense_data = SS_WRITE_ERROR;
962 /*-------------------------------------------------------------------------*/
964 static void invalidate_sub(struct fsg_lun *curlun)
966 struct file *filp = curlun->filp;
967 struct inode *inode = file_inode(filp);
970 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
971 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
974 static int do_verify(struct fsg_common *common)
976 struct fsg_lun *curlun = common->curlun;
978 u32 verification_length;
979 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
980 loff_t file_offset, file_offset_tmp;
986 * Get the starting Logical Block Address and check that it's
989 lba = get_unaligned_be32(&common->cmnd[2]);
990 if (lba >= curlun->num_sectors) {
991 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
996 * We allow DPO (Disable Page Out = don't save data in the
997 * cache) but we don't implement it.
999 if (common->cmnd[1] & ~0x10) {
1000 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1004 verification_length = get_unaligned_be16(&common->cmnd[7]);
1005 if (unlikely(verification_length == 0))
1006 return -EIO; /* No default reply */
1008 /* Prepare to carry out the file verify */
1009 amount_left = verification_length << curlun->blkbits;
1010 file_offset = ((loff_t) lba) << curlun->blkbits;
1012 /* Write out all the dirty buffers before invalidating them */
1013 fsg_lun_fsync_sub(curlun);
1014 if (signal_pending(current))
1017 invalidate_sub(curlun);
1018 if (signal_pending(current))
1021 /* Just try to read the requested blocks */
1022 while (amount_left > 0) {
1024 * Figure out how much we need to read:
1025 * Try to read the remaining amount, but not more than
1027 * And don't try to read past the end of the file.
1029 amount = min(amount_left, FSG_BUFLEN);
1030 amount = min((loff_t)amount,
1031 curlun->file_length - file_offset);
1033 curlun->sense_data =
1034 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1035 curlun->sense_data_info =
1036 file_offset >> curlun->blkbits;
1037 curlun->info_valid = 1;
1041 /* Perform the read */
1042 file_offset_tmp = file_offset;
1043 nread = vfs_read(curlun->filp,
1044 (char __user *) bh->buf,
1045 amount, &file_offset_tmp);
1046 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1047 (unsigned long long) file_offset,
1049 if (signal_pending(current))
1053 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1055 } else if (nread < amount) {
1056 LDBG(curlun, "partial file verify: %d/%u\n",
1057 (int)nread, amount);
1058 nread = round_down(nread, curlun->blksize);
1061 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1062 curlun->sense_data_info =
1063 file_offset >> curlun->blkbits;
1064 curlun->info_valid = 1;
1067 file_offset += nread;
1068 amount_left -= nread;
1074 /*-------------------------------------------------------------------------*/
1076 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1078 struct fsg_lun *curlun = common->curlun;
1079 u8 *buf = (u8 *) bh->buf;
1081 if (!curlun) { /* Unsupported LUNs are okay */
1082 common->bad_lun_okay = 1;
1084 buf[0] = 0x7f; /* Unsupported, no device-type */
1085 buf[4] = 31; /* Additional length */
1089 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1090 buf[1] = curlun->removable ? 0x80 : 0;
1091 buf[2] = 2; /* ANSI SCSI level 2 */
1092 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1093 buf[4] = 31; /* Additional length */
1094 buf[5] = 0; /* No special options */
1097 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1101 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1103 struct fsg_lun *curlun = common->curlun;
1104 u8 *buf = (u8 *) bh->buf;
1109 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1111 * If a REQUEST SENSE command is received from an initiator
1112 * with a pending unit attention condition (before the target
1113 * generates the contingent allegiance condition), then the
1114 * target shall either:
1115 * a) report any pending sense data and preserve the unit
1116 * attention condition on the logical unit, or,
1117 * b) report the unit attention condition, may discard any
1118 * pending sense data, and clear the unit attention
1119 * condition on the logical unit for that initiator.
1121 * FSG normally uses option a); enable this code to use option b).
1124 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1125 curlun->sense_data = curlun->unit_attention_data;
1126 curlun->unit_attention_data = SS_NO_SENSE;
1130 if (!curlun) { /* Unsupported LUNs are okay */
1131 common->bad_lun_okay = 1;
1132 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1136 sd = curlun->sense_data;
1137 sdinfo = curlun->sense_data_info;
1138 valid = curlun->info_valid << 7;
1139 curlun->sense_data = SS_NO_SENSE;
1140 curlun->sense_data_info = 0;
1141 curlun->info_valid = 0;
1145 buf[0] = valid | 0x70; /* Valid, current error */
1147 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1148 buf[7] = 18 - 8; /* Additional sense length */
1154 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1156 struct fsg_lun *curlun = common->curlun;
1157 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1158 int pmi = common->cmnd[8];
1159 u8 *buf = (u8 *)bh->buf;
1161 /* Check the PMI and LBA fields */
1162 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1163 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1167 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1168 /* Max logical block */
1169 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1173 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1175 struct fsg_lun *curlun = common->curlun;
1176 int msf = common->cmnd[1] & 0x02;
1177 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1178 u8 *buf = (u8 *)bh->buf;
1180 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1181 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1184 if (lba >= curlun->num_sectors) {
1185 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1190 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1191 store_cdrom_address(&buf[4], msf, lba);
1195 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1197 struct fsg_lun *curlun = common->curlun;
1198 int msf = common->cmnd[1] & 0x02;
1199 int start_track = common->cmnd[6];
1200 u8 *buf = (u8 *)bh->buf;
1202 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1204 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1209 buf[1] = (20-2); /* TOC data length */
1210 buf[2] = 1; /* First track number */
1211 buf[3] = 1; /* Last track number */
1212 buf[5] = 0x16; /* Data track, copying allowed */
1213 buf[6] = 0x01; /* Only track is number 1 */
1214 store_cdrom_address(&buf[8], msf, 0);
1216 buf[13] = 0x16; /* Lead-out track is data */
1217 buf[14] = 0xAA; /* Lead-out track number */
1218 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1222 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1224 struct fsg_lun *curlun = common->curlun;
1225 int mscmnd = common->cmnd[0];
1226 u8 *buf = (u8 *) bh->buf;
1229 int changeable_values, all_pages;
1233 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1234 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1237 pc = common->cmnd[2] >> 6;
1238 page_code = common->cmnd[2] & 0x3f;
1240 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1243 changeable_values = (pc == 1);
1244 all_pages = (page_code == 0x3f);
1247 * Write the mode parameter header. Fixed values are: default
1248 * medium type, no cache control (DPOFUA), and no block descriptors.
1249 * The only variable value is the WriteProtect bit. We will fill in
1250 * the mode data length later.
1253 if (mscmnd == MODE_SENSE) {
1254 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1257 } else { /* MODE_SENSE_10 */
1258 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1260 limit = 65535; /* Should really be FSG_BUFLEN */
1263 /* No block descriptors */
1266 * The mode pages, in numerical order. The only page we support
1267 * is the Caching page.
1269 if (page_code == 0x08 || all_pages) {
1271 buf[0] = 0x08; /* Page code */
1272 buf[1] = 10; /* Page length */
1273 memset(buf+2, 0, 10); /* None of the fields are changeable */
1275 if (!changeable_values) {
1276 buf[2] = 0x04; /* Write cache enable, */
1277 /* Read cache not disabled */
1278 /* No cache retention priorities */
1279 put_unaligned_be16(0xffff, &buf[4]);
1280 /* Don't disable prefetch */
1281 /* Minimum prefetch = 0 */
1282 put_unaligned_be16(0xffff, &buf[8]);
1283 /* Maximum prefetch */
1284 put_unaligned_be16(0xffff, &buf[10]);
1285 /* Maximum prefetch ceiling */
1291 * Check that a valid page was requested and the mode data length
1295 if (!valid_page || len > limit) {
1296 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1300 /* Store the mode data length */
1301 if (mscmnd == MODE_SENSE)
1304 put_unaligned_be16(len - 2, buf0);
1308 static int do_start_stop(struct fsg_common *common)
1310 struct fsg_lun *curlun = common->curlun;
1315 } else if (!curlun->removable) {
1316 curlun->sense_data = SS_INVALID_COMMAND;
1318 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1319 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1320 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1324 loej = common->cmnd[4] & 0x02;
1325 start = common->cmnd[4] & 0x01;
1328 * Our emulation doesn't support mounting; the medium is
1329 * available for use as soon as it is loaded.
1332 if (!fsg_lun_is_open(curlun)) {
1333 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1339 /* Are we allowed to unload the media? */
1340 if (curlun->prevent_medium_removal) {
1341 LDBG(curlun, "unload attempt prevented\n");
1342 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1349 up_read(&common->filesem);
1350 down_write(&common->filesem);
1351 fsg_lun_close(curlun);
1352 up_write(&common->filesem);
1353 down_read(&common->filesem);
1358 static int do_prevent_allow(struct fsg_common *common)
1360 struct fsg_lun *curlun = common->curlun;
1363 if (!common->curlun) {
1365 } else if (!common->curlun->removable) {
1366 common->curlun->sense_data = SS_INVALID_COMMAND;
1370 prevent = common->cmnd[4] & 0x01;
1371 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1372 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1376 if (curlun->prevent_medium_removal && !prevent)
1377 fsg_lun_fsync_sub(curlun);
1378 curlun->prevent_medium_removal = prevent;
1382 static int do_read_format_capacities(struct fsg_common *common,
1383 struct fsg_buffhd *bh)
1385 struct fsg_lun *curlun = common->curlun;
1386 u8 *buf = (u8 *) bh->buf;
1388 buf[0] = buf[1] = buf[2] = 0;
1389 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1392 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1393 /* Number of blocks */
1394 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1395 buf[4] = 0x02; /* Current capacity */
1399 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1401 struct fsg_lun *curlun = common->curlun;
1403 /* We don't support MODE SELECT */
1405 curlun->sense_data = SS_INVALID_COMMAND;
1410 /*-------------------------------------------------------------------------*/
1412 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1416 rc = fsg_set_halt(fsg, fsg->bulk_in);
1418 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1420 if (rc != -EAGAIN) {
1421 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1426 /* Wait for a short time and then try again */
1427 if (msleep_interruptible(100) != 0)
1429 rc = usb_ep_set_halt(fsg->bulk_in);
1434 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1438 DBG(fsg, "bulk-in set wedge\n");
1439 rc = usb_ep_set_wedge(fsg->bulk_in);
1441 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1443 if (rc != -EAGAIN) {
1444 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1449 /* Wait for a short time and then try again */
1450 if (msleep_interruptible(100) != 0)
1452 rc = usb_ep_set_wedge(fsg->bulk_in);
1457 static int throw_away_data(struct fsg_common *common)
1459 struct fsg_buffhd *bh;
1463 for (bh = common->next_buffhd_to_drain;
1464 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1465 bh = common->next_buffhd_to_drain) {
1467 /* Throw away the data in a filled buffer */
1468 if (bh->state == BUF_STATE_FULL) {
1470 bh->state = BUF_STATE_EMPTY;
1471 common->next_buffhd_to_drain = bh->next;
1473 /* A short packet or an error ends everything */
1474 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1475 bh->outreq->status != 0) {
1476 raise_exception(common,
1477 FSG_STATE_ABORT_BULK_OUT);
1483 /* Try to submit another request if we need one */
1484 bh = common->next_buffhd_to_fill;
1485 if (bh->state == BUF_STATE_EMPTY
1486 && common->usb_amount_left > 0) {
1487 amount = min(common->usb_amount_left, FSG_BUFLEN);
1490 * Except at the end of the transfer, amount will be
1491 * equal to the buffer size, which is divisible by
1492 * the bulk-out maxpacket size.
1494 set_bulk_out_req_length(common, bh, amount);
1495 if (!start_out_transfer(common, bh))
1496 /* Dunno what to do if common->fsg is NULL */
1498 common->next_buffhd_to_fill = bh->next;
1499 common->usb_amount_left -= amount;
1503 /* Otherwise wait for something to happen */
1504 rc = sleep_thread(common);
1511 static int finish_reply(struct fsg_common *common)
1513 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1516 switch (common->data_dir) {
1518 break; /* Nothing to send */
1521 * If we don't know whether the host wants to read or write,
1522 * this must be CB or CBI with an unknown command. We mustn't
1523 * try to send or receive any data. So stall both bulk pipes
1524 * if we can and wait for a reset.
1526 case DATA_DIR_UNKNOWN:
1527 if (!common->can_stall) {
1529 } else if (fsg_is_set(common)) {
1530 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1531 rc = halt_bulk_in_endpoint(common->fsg);
1533 /* Don't know what to do if common->fsg is NULL */
1538 /* All but the last buffer of data must have already been sent */
1539 case DATA_DIR_TO_HOST:
1540 if (common->data_size == 0) {
1541 /* Nothing to send */
1543 /* Don't know what to do if common->fsg is NULL */
1544 } else if (!fsg_is_set(common)) {
1547 /* If there's no residue, simply send the last buffer */
1548 } else if (common->residue == 0) {
1549 bh->inreq->zero = 0;
1550 if (!start_in_transfer(common, bh))
1552 common->next_buffhd_to_fill = bh->next;
1555 * For Bulk-only, mark the end of the data with a short
1556 * packet. If we are allowed to stall, halt the bulk-in
1557 * endpoint. (Note: This violates the Bulk-Only Transport
1558 * specification, which requires us to pad the data if we
1559 * don't halt the endpoint. Presumably nobody will mind.)
1562 bh->inreq->zero = 1;
1563 if (!start_in_transfer(common, bh))
1565 common->next_buffhd_to_fill = bh->next;
1566 if (common->can_stall)
1567 rc = halt_bulk_in_endpoint(common->fsg);
1572 * We have processed all we want from the data the host has sent.
1573 * There may still be outstanding bulk-out requests.
1575 case DATA_DIR_FROM_HOST:
1576 if (common->residue == 0) {
1577 /* Nothing to receive */
1579 /* Did the host stop sending unexpectedly early? */
1580 } else if (common->short_packet_received) {
1581 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1585 * We haven't processed all the incoming data. Even though
1586 * we may be allowed to stall, doing so would cause a race.
1587 * The controller may already have ACK'ed all the remaining
1588 * bulk-out packets, in which case the host wouldn't see a
1589 * STALL. Not realizing the endpoint was halted, it wouldn't
1590 * clear the halt -- leading to problems later on.
1593 } else if (common->can_stall) {
1594 if (fsg_is_set(common))
1595 fsg_set_halt(common->fsg,
1596 common->fsg->bulk_out);
1597 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1602 * We can't stall. Read in the excess data and throw it
1606 rc = throw_away_data(common);
1613 static int send_status(struct fsg_common *common)
1615 struct fsg_lun *curlun = common->curlun;
1616 struct fsg_buffhd *bh;
1617 struct bulk_cs_wrap *csw;
1619 u8 status = US_BULK_STAT_OK;
1622 /* Wait for the next buffer to become available */
1623 bh = common->next_buffhd_to_fill;
1624 while (bh->state != BUF_STATE_EMPTY) {
1625 rc = sleep_thread(common);
1631 sd = curlun->sense_data;
1632 sdinfo = curlun->sense_data_info;
1633 } else if (common->bad_lun_okay)
1636 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1638 if (common->phase_error) {
1639 DBG(common, "sending phase-error status\n");
1640 status = US_BULK_STAT_PHASE;
1641 sd = SS_INVALID_COMMAND;
1642 } else if (sd != SS_NO_SENSE) {
1643 DBG(common, "sending command-failure status\n");
1644 status = US_BULK_STAT_FAIL;
1645 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1647 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1650 /* Store and send the Bulk-only CSW */
1651 csw = (void *)bh->buf;
1653 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1654 csw->Tag = common->tag;
1655 csw->Residue = cpu_to_le32(common->residue);
1656 csw->Status = status;
1658 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1659 bh->inreq->zero = 0;
1660 if (!start_in_transfer(common, bh))
1661 /* Don't know what to do if common->fsg is NULL */
1664 common->next_buffhd_to_fill = bh->next;
1669 /*-------------------------------------------------------------------------*/
1672 * Check whether the command is properly formed and whether its data size
1673 * and direction agree with the values we already have.
1675 static int check_command(struct fsg_common *common, int cmnd_size,
1676 enum data_direction data_dir, unsigned int mask,
1677 int needs_medium, const char *name)
1680 unsigned int lun = common->cmnd[1] >> 5;
1681 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1683 struct fsg_lun *curlun;
1686 if (common->data_dir != DATA_DIR_UNKNOWN)
1687 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1689 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1690 name, cmnd_size, dirletter[(int) data_dir],
1691 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1694 * We can't reply at all until we know the correct data direction
1697 if (common->data_size_from_cmnd == 0)
1698 data_dir = DATA_DIR_NONE;
1699 if (common->data_size < common->data_size_from_cmnd) {
1701 * Host data size < Device data size is a phase error.
1702 * Carry out the command, but only transfer as much as
1705 common->data_size_from_cmnd = common->data_size;
1706 common->phase_error = 1;
1708 common->residue = common->data_size;
1709 common->usb_amount_left = common->data_size;
1711 /* Conflicting data directions is a phase error */
1712 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1713 common->phase_error = 1;
1717 /* Verify the length of the command itself */
1718 if (cmnd_size != common->cmnd_size) {
1721 * Special case workaround: There are plenty of buggy SCSI
1722 * implementations. Many have issues with cbw->Length
1723 * field passing a wrong command size. For those cases we
1724 * always try to work around the problem by using the length
1725 * sent by the host side provided it is at least as large
1726 * as the correct command length.
1727 * Examples of such cases would be MS-Windows, which issues
1728 * REQUEST SENSE with cbw->Length == 12 where it should
1729 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1730 * REQUEST SENSE with cbw->Length == 10 where it should
1733 if (cmnd_size <= common->cmnd_size) {
1734 DBG(common, "%s is buggy! Expected length %d "
1735 "but we got %d\n", name,
1736 cmnd_size, common->cmnd_size);
1737 cmnd_size = common->cmnd_size;
1739 common->phase_error = 1;
1744 /* Check that the LUN values are consistent */
1745 if (common->lun != lun)
1746 DBG(common, "using LUN %u from CBW, not LUN %u from CDB\n",
1750 curlun = common->curlun;
1752 if (common->cmnd[0] != REQUEST_SENSE) {
1753 curlun->sense_data = SS_NO_SENSE;
1754 curlun->sense_data_info = 0;
1755 curlun->info_valid = 0;
1758 common->bad_lun_okay = 0;
1761 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1762 * to use unsupported LUNs; all others may not.
1764 if (common->cmnd[0] != INQUIRY &&
1765 common->cmnd[0] != REQUEST_SENSE) {
1766 DBG(common, "unsupported LUN %u\n", common->lun);
1772 * If a unit attention condition exists, only INQUIRY and
1773 * REQUEST SENSE commands are allowed; anything else must fail.
1775 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1776 common->cmnd[0] != INQUIRY &&
1777 common->cmnd[0] != REQUEST_SENSE) {
1778 curlun->sense_data = curlun->unit_attention_data;
1779 curlun->unit_attention_data = SS_NO_SENSE;
1783 /* Check that only command bytes listed in the mask are non-zero */
1784 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1785 for (i = 1; i < cmnd_size; ++i) {
1786 if (common->cmnd[i] && !(mask & (1 << i))) {
1788 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1793 /* If the medium isn't mounted and the command needs to access
1794 * it, return an error. */
1795 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1796 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1803 /* wrapper of check_command for data size in blocks handling */
1804 static int check_command_size_in_blocks(struct fsg_common *common,
1805 int cmnd_size, enum data_direction data_dir,
1806 unsigned int mask, int needs_medium, const char *name)
1809 common->data_size_from_cmnd <<= common->curlun->blkbits;
1810 return check_command(common, cmnd_size, data_dir,
1811 mask, needs_medium, name);
1814 static int do_scsi_command(struct fsg_common *common)
1816 struct fsg_buffhd *bh;
1818 int reply = -EINVAL;
1820 static char unknown[16];
1824 /* Wait for the next buffer to become available for data or status */
1825 bh = common->next_buffhd_to_fill;
1826 common->next_buffhd_to_drain = bh;
1827 while (bh->state != BUF_STATE_EMPTY) {
1828 rc = sleep_thread(common);
1832 common->phase_error = 0;
1833 common->short_packet_received = 0;
1835 down_read(&common->filesem); /* We're using the backing file */
1836 switch (common->cmnd[0]) {
1839 common->data_size_from_cmnd = common->cmnd[4];
1840 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1844 reply = do_inquiry(common, bh);
1848 common->data_size_from_cmnd = common->cmnd[4];
1849 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1853 reply = do_mode_select(common, bh);
1856 case MODE_SELECT_10:
1857 common->data_size_from_cmnd =
1858 get_unaligned_be16(&common->cmnd[7]);
1859 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1863 reply = do_mode_select(common, bh);
1867 common->data_size_from_cmnd = common->cmnd[4];
1868 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1869 (1<<1) | (1<<2) | (1<<4), 0,
1872 reply = do_mode_sense(common, bh);
1876 common->data_size_from_cmnd =
1877 get_unaligned_be16(&common->cmnd[7]);
1878 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1879 (1<<1) | (1<<2) | (3<<7), 0,
1882 reply = do_mode_sense(common, bh);
1885 case ALLOW_MEDIUM_REMOVAL:
1886 common->data_size_from_cmnd = 0;
1887 reply = check_command(common, 6, DATA_DIR_NONE,
1889 "PREVENT-ALLOW MEDIUM REMOVAL");
1891 reply = do_prevent_allow(common);
1895 i = common->cmnd[4];
1896 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1897 reply = check_command_size_in_blocks(common, 6,
1902 reply = do_read(common);
1906 common->data_size_from_cmnd =
1907 get_unaligned_be16(&common->cmnd[7]);
1908 reply = check_command_size_in_blocks(common, 10,
1910 (1<<1) | (0xf<<2) | (3<<7), 1,
1913 reply = do_read(common);
1917 common->data_size_from_cmnd =
1918 get_unaligned_be32(&common->cmnd[6]);
1919 reply = check_command_size_in_blocks(common, 12,
1921 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1924 reply = do_read(common);
1928 common->data_size_from_cmnd = 8;
1929 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1930 (0xf<<2) | (1<<8), 1,
1933 reply = do_read_capacity(common, bh);
1937 if (!common->curlun || !common->curlun->cdrom)
1939 common->data_size_from_cmnd =
1940 get_unaligned_be16(&common->cmnd[7]);
1941 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1942 (3<<7) | (0x1f<<1), 1,
1945 reply = do_read_header(common, bh);
1949 if (!common->curlun || !common->curlun->cdrom)
1951 common->data_size_from_cmnd =
1952 get_unaligned_be16(&common->cmnd[7]);
1953 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1957 reply = do_read_toc(common, bh);
1960 case READ_FORMAT_CAPACITIES:
1961 common->data_size_from_cmnd =
1962 get_unaligned_be16(&common->cmnd[7]);
1963 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1965 "READ FORMAT CAPACITIES");
1967 reply = do_read_format_capacities(common, bh);
1971 common->data_size_from_cmnd = common->cmnd[4];
1972 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1976 reply = do_request_sense(common, bh);
1980 common->data_size_from_cmnd = 0;
1981 reply = check_command(common, 6, DATA_DIR_NONE,
1985 reply = do_start_stop(common);
1988 case SYNCHRONIZE_CACHE:
1989 common->data_size_from_cmnd = 0;
1990 reply = check_command(common, 10, DATA_DIR_NONE,
1991 (0xf<<2) | (3<<7), 1,
1992 "SYNCHRONIZE CACHE");
1994 reply = do_synchronize_cache(common);
1997 case TEST_UNIT_READY:
1998 common->data_size_from_cmnd = 0;
1999 reply = check_command(common, 6, DATA_DIR_NONE,
2005 * Although optional, this command is used by MS-Windows. We
2006 * support a minimal version: BytChk must be 0.
2009 common->data_size_from_cmnd = 0;
2010 reply = check_command(common, 10, DATA_DIR_NONE,
2011 (1<<1) | (0xf<<2) | (3<<7), 1,
2014 reply = do_verify(common);
2018 i = common->cmnd[4];
2019 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2020 reply = check_command_size_in_blocks(common, 6,
2025 reply = do_write(common);
2029 common->data_size_from_cmnd =
2030 get_unaligned_be16(&common->cmnd[7]);
2031 reply = check_command_size_in_blocks(common, 10,
2033 (1<<1) | (0xf<<2) | (3<<7), 1,
2036 reply = do_write(common);
2040 common->data_size_from_cmnd =
2041 get_unaligned_be32(&common->cmnd[6]);
2042 reply = check_command_size_in_blocks(common, 12,
2044 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2047 reply = do_write(common);
2051 * Some mandatory commands that we recognize but don't implement.
2052 * They don't mean much in this setting. It's left as an exercise
2053 * for anyone interested to implement RESERVE and RELEASE in terms
2059 case SEND_DIAGNOSTIC:
2064 common->data_size_from_cmnd = 0;
2065 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2066 reply = check_command(common, common->cmnd_size,
2067 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2069 common->curlun->sense_data = SS_INVALID_COMMAND;
2074 up_read(&common->filesem);
2076 if (reply == -EINTR || signal_pending(current))
2079 /* Set up the single reply buffer for finish_reply() */
2080 if (reply == -EINVAL)
2081 reply = 0; /* Error reply length */
2082 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2083 reply = min((u32)reply, common->data_size_from_cmnd);
2084 bh->inreq->length = reply;
2085 bh->state = BUF_STATE_FULL;
2086 common->residue -= reply;
2087 } /* Otherwise it's already set */
2093 /*-------------------------------------------------------------------------*/
2095 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2097 struct usb_request *req = bh->outreq;
2098 struct bulk_cb_wrap *cbw = req->buf;
2099 struct fsg_common *common = fsg->common;
2101 /* Was this a real packet? Should it be ignored? */
2102 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2105 /* Is the CBW valid? */
2106 if (req->actual != US_BULK_CB_WRAP_LEN ||
2107 cbw->Signature != cpu_to_le32(
2109 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2111 le32_to_cpu(cbw->Signature));
2114 * The Bulk-only spec says we MUST stall the IN endpoint
2115 * (6.6.1), so it's unavoidable. It also says we must
2116 * retain this state until the next reset, but there's
2117 * no way to tell the controller driver it should ignore
2118 * Clear-Feature(HALT) requests.
2120 * We aren't required to halt the OUT endpoint; instead
2121 * we can simply accept and discard any data received
2122 * until the next reset.
2124 wedge_bulk_in_endpoint(fsg);
2125 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2129 /* Is the CBW meaningful? */
2130 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2131 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2132 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2134 cbw->Lun, cbw->Flags, cbw->Length);
2137 * We can do anything we want here, so let's stall the
2138 * bulk pipes if we are allowed to.
2140 if (common->can_stall) {
2141 fsg_set_halt(fsg, fsg->bulk_out);
2142 halt_bulk_in_endpoint(fsg);
2147 /* Save the command for later */
2148 common->cmnd_size = cbw->Length;
2149 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2150 if (cbw->Flags & US_BULK_FLAG_IN)
2151 common->data_dir = DATA_DIR_TO_HOST;
2153 common->data_dir = DATA_DIR_FROM_HOST;
2154 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2155 if (common->data_size == 0)
2156 common->data_dir = DATA_DIR_NONE;
2157 common->lun = cbw->Lun;
2158 if (common->lun < common->nluns)
2159 common->curlun = common->luns[common->lun];
2161 common->curlun = NULL;
2162 common->tag = cbw->Tag;
2166 static int get_next_command(struct fsg_common *common)
2168 struct fsg_buffhd *bh;
2171 /* Wait for the next buffer to become available */
2172 bh = common->next_buffhd_to_fill;
2173 while (bh->state != BUF_STATE_EMPTY) {
2174 rc = sleep_thread(common);
2179 /* Queue a request to read a Bulk-only CBW */
2180 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2181 if (!start_out_transfer(common, bh))
2182 /* Don't know what to do if common->fsg is NULL */
2186 * We will drain the buffer in software, which means we
2187 * can reuse it for the next filling. No need to advance
2188 * next_buffhd_to_fill.
2191 /* Wait for the CBW to arrive */
2192 while (bh->state != BUF_STATE_FULL) {
2193 rc = sleep_thread(common);
2198 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2199 bh->state = BUF_STATE_EMPTY;
2205 /*-------------------------------------------------------------------------*/
2207 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2208 struct usb_request **preq)
2210 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2213 ERROR(common, "can't allocate request for %s\n", ep->name);
2217 /* Reset interface setting and re-init endpoint state (toggle etc). */
2218 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2220 struct fsg_dev *fsg;
2223 if (common->running)
2224 DBG(common, "reset interface\n");
2227 /* Deallocate the requests */
2231 for (i = 0; i < common->fsg_num_buffers; ++i) {
2232 struct fsg_buffhd *bh = &common->buffhds[i];
2235 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2239 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2244 /* Disable the endpoints */
2245 if (fsg->bulk_in_enabled) {
2246 usb_ep_disable(fsg->bulk_in);
2247 fsg->bulk_in->driver_data = NULL;
2248 fsg->bulk_in_enabled = 0;
2250 if (fsg->bulk_out_enabled) {
2251 usb_ep_disable(fsg->bulk_out);
2252 fsg->bulk_out->driver_data = NULL;
2253 fsg->bulk_out_enabled = 0;
2257 wake_up(&common->fsg_wait);
2260 common->running = 0;
2264 common->fsg = new_fsg;
2267 /* Enable the endpoints */
2268 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2271 rc = usb_ep_enable(fsg->bulk_in);
2274 fsg->bulk_in->driver_data = common;
2275 fsg->bulk_in_enabled = 1;
2277 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2281 rc = usb_ep_enable(fsg->bulk_out);
2284 fsg->bulk_out->driver_data = common;
2285 fsg->bulk_out_enabled = 1;
2286 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2287 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2289 /* Allocate the requests */
2290 for (i = 0; i < common->fsg_num_buffers; ++i) {
2291 struct fsg_buffhd *bh = &common->buffhds[i];
2293 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2296 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2299 bh->inreq->buf = bh->outreq->buf = bh->buf;
2300 bh->inreq->context = bh->outreq->context = bh;
2301 bh->inreq->complete = bulk_in_complete;
2302 bh->outreq->complete = bulk_out_complete;
2305 common->running = 1;
2306 for (i = 0; i < common->nluns; ++i)
2307 if (common->luns[i])
2308 common->luns[i]->unit_attention_data =
2314 /****************************** ALT CONFIGS ******************************/
2316 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2318 struct fsg_dev *fsg = fsg_from_func(f);
2319 fsg->common->new_fsg = fsg;
2320 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2321 return USB_GADGET_DELAYED_STATUS;
2324 static void fsg_disable(struct usb_function *f)
2326 struct fsg_dev *fsg = fsg_from_func(f);
2327 fsg->common->new_fsg = NULL;
2328 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2332 /*-------------------------------------------------------------------------*/
2334 static void handle_exception(struct fsg_common *common)
2338 struct fsg_buffhd *bh;
2339 enum fsg_state old_state;
2340 struct fsg_lun *curlun;
2341 unsigned int exception_req_tag;
2344 * Clear the existing signals. Anything but SIGUSR1 is converted
2345 * into a high-priority EXIT exception.
2349 dequeue_signal_lock(current, ¤t->blocked, &info);
2352 if (sig != SIGUSR1) {
2353 if (common->state < FSG_STATE_EXIT)
2354 DBG(common, "Main thread exiting on signal\n");
2355 raise_exception(common, FSG_STATE_EXIT);
2359 /* Cancel all the pending transfers */
2360 if (likely(common->fsg)) {
2361 for (i = 0; i < common->fsg_num_buffers; ++i) {
2362 bh = &common->buffhds[i];
2364 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2365 if (bh->outreq_busy)
2366 usb_ep_dequeue(common->fsg->bulk_out,
2370 /* Wait until everything is idle */
2373 for (i = 0; i < common->fsg_num_buffers; ++i) {
2374 bh = &common->buffhds[i];
2375 num_active += bh->inreq_busy + bh->outreq_busy;
2377 if (num_active == 0)
2379 if (sleep_thread(common))
2383 /* Clear out the controller's fifos */
2384 if (common->fsg->bulk_in_enabled)
2385 usb_ep_fifo_flush(common->fsg->bulk_in);
2386 if (common->fsg->bulk_out_enabled)
2387 usb_ep_fifo_flush(common->fsg->bulk_out);
2391 * Reset the I/O buffer states and pointers, the SCSI
2392 * state, and the exception. Then invoke the handler.
2394 spin_lock_irq(&common->lock);
2396 for (i = 0; i < common->fsg_num_buffers; ++i) {
2397 bh = &common->buffhds[i];
2398 bh->state = BUF_STATE_EMPTY;
2400 common->next_buffhd_to_fill = &common->buffhds[0];
2401 common->next_buffhd_to_drain = &common->buffhds[0];
2402 exception_req_tag = common->exception_req_tag;
2403 old_state = common->state;
2405 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2406 common->state = FSG_STATE_STATUS_PHASE;
2408 for (i = 0; i < common->nluns; ++i) {
2409 curlun = common->luns[i];
2412 curlun->prevent_medium_removal = 0;
2413 curlun->sense_data = SS_NO_SENSE;
2414 curlun->unit_attention_data = SS_NO_SENSE;
2415 curlun->sense_data_info = 0;
2416 curlun->info_valid = 0;
2418 common->state = FSG_STATE_IDLE;
2420 spin_unlock_irq(&common->lock);
2422 /* Carry out any extra actions required for the exception */
2423 switch (old_state) {
2424 case FSG_STATE_ABORT_BULK_OUT:
2425 send_status(common);
2426 spin_lock_irq(&common->lock);
2427 if (common->state == FSG_STATE_STATUS_PHASE)
2428 common->state = FSG_STATE_IDLE;
2429 spin_unlock_irq(&common->lock);
2432 case FSG_STATE_RESET:
2434 * In case we were forced against our will to halt a
2435 * bulk endpoint, clear the halt now. (The SuperH UDC
2438 if (!fsg_is_set(common))
2440 if (test_and_clear_bit(IGNORE_BULK_OUT,
2441 &common->fsg->atomic_bitflags))
2442 usb_ep_clear_halt(common->fsg->bulk_in);
2444 if (common->ep0_req_tag == exception_req_tag)
2445 ep0_queue(common); /* Complete the status stage */
2448 * Technically this should go here, but it would only be
2449 * a waste of time. Ditto for the INTERFACE_CHANGE and
2450 * CONFIG_CHANGE cases.
2452 /* for (i = 0; i < common->nluns; ++i) */
2453 /* if (common->luns[i]) */
2454 /* common->luns[i]->unit_attention_data = */
2455 /* SS_RESET_OCCURRED; */
2458 case FSG_STATE_CONFIG_CHANGE:
2459 do_set_interface(common, common->new_fsg);
2460 if (common->new_fsg)
2461 usb_composite_setup_continue(common->cdev);
2464 case FSG_STATE_EXIT:
2465 case FSG_STATE_TERMINATED:
2466 do_set_interface(common, NULL); /* Free resources */
2467 spin_lock_irq(&common->lock);
2468 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2469 spin_unlock_irq(&common->lock);
2472 case FSG_STATE_INTERFACE_CHANGE:
2473 case FSG_STATE_DISCONNECT:
2474 case FSG_STATE_COMMAND_PHASE:
2475 case FSG_STATE_DATA_PHASE:
2476 case FSG_STATE_STATUS_PHASE:
2477 case FSG_STATE_IDLE:
2483 /*-------------------------------------------------------------------------*/
2485 static int fsg_main_thread(void *common_)
2487 struct fsg_common *common = common_;
2490 * Allow the thread to be killed by a signal, but set the signal mask
2491 * to block everything but INT, TERM, KILL, and USR1.
2493 allow_signal(SIGINT);
2494 allow_signal(SIGTERM);
2495 allow_signal(SIGKILL);
2496 allow_signal(SIGUSR1);
2498 /* Allow the thread to be frozen */
2502 * Arrange for userspace references to be interpreted as kernel
2503 * pointers. That way we can pass a kernel pointer to a routine
2504 * that expects a __user pointer and it will work okay.
2509 while (common->state != FSG_STATE_TERMINATED) {
2510 if (exception_in_progress(common) || signal_pending(current)) {
2511 handle_exception(common);
2515 if (!common->running) {
2516 sleep_thread(common);
2520 if (get_next_command(common))
2523 spin_lock_irq(&common->lock);
2524 if (!exception_in_progress(common))
2525 common->state = FSG_STATE_DATA_PHASE;
2526 spin_unlock_irq(&common->lock);
2528 if (do_scsi_command(common) || finish_reply(common))
2531 spin_lock_irq(&common->lock);
2532 if (!exception_in_progress(common))
2533 common->state = FSG_STATE_STATUS_PHASE;
2534 spin_unlock_irq(&common->lock);
2536 if (send_status(common))
2539 spin_lock_irq(&common->lock);
2540 if (!exception_in_progress(common))
2541 common->state = FSG_STATE_IDLE;
2542 spin_unlock_irq(&common->lock);
2545 spin_lock_irq(&common->lock);
2546 common->thread_task = NULL;
2547 spin_unlock_irq(&common->lock);
2549 if (!common->ops || !common->ops->thread_exits
2550 || common->ops->thread_exits(common) < 0) {
2551 struct fsg_lun **curlun_it = common->luns;
2552 unsigned i = common->nluns;
2554 down_write(&common->filesem);
2555 for (; i--; ++curlun_it) {
2556 struct fsg_lun *curlun = *curlun_it;
2557 if (!curlun || !fsg_lun_is_open(curlun))
2560 fsg_lun_close(curlun);
2561 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2563 up_write(&common->filesem);
2566 /* Let fsg_unbind() know the thread has exited */
2567 complete_and_exit(&common->thread_notifier, 0);
2571 /*************************** DEVICE ATTRIBUTES ***************************/
2573 static ssize_t ro_show(struct device *dev, struct device_attribute *attr, char *buf)
2575 return fsg_show_ro(dev, attr, buf);
2578 static ssize_t nofua_show(struct device *dev, struct device_attribute *attr,
2581 return fsg_show_nofua(dev, attr, buf);
2584 static ssize_t file_show(struct device *dev, struct device_attribute *attr,
2587 return fsg_show_file(dev, attr, buf);
2590 static ssize_t ro_store(struct device *dev, struct device_attribute *attr,
2591 const char *buf, size_t count)
2593 return fsg_store_ro(dev, attr, buf, count);
2596 static ssize_t nofua_store(struct device *dev, struct device_attribute *attr,
2597 const char *buf, size_t count)
2599 return fsg_store_nofua(dev, attr, buf, count);
2602 static ssize_t file_store(struct device *dev, struct device_attribute *attr,
2603 const char *buf, size_t count)
2605 return fsg_store_file(dev, attr, buf, count);
2608 static DEVICE_ATTR_RW(ro);
2609 static DEVICE_ATTR_RW(nofua);
2610 static DEVICE_ATTR_RW(file);
2612 static struct device_attribute dev_attr_ro_cdrom = __ATTR_RO(ro);
2613 static struct device_attribute dev_attr_file_nonremovable = __ATTR_RO(file);
2616 /****************************** FSG COMMON ******************************/
2618 static void fsg_common_release(struct kref *ref);
2620 static void fsg_lun_release(struct device *dev)
2622 /* Nothing needs to be done */
2625 void fsg_common_get(struct fsg_common *common)
2627 kref_get(&common->ref);
2630 void fsg_common_put(struct fsg_common *common)
2632 kref_put(&common->ref, fsg_common_release);
2635 /* check if fsg_num_buffers is within a valid range */
2636 static inline int fsg_num_buffers_validate(unsigned int fsg_num_buffers)
2638 if (fsg_num_buffers >= 2 && fsg_num_buffers <= 4)
2640 pr_err("fsg_num_buffers %u is out of range (%d to %d)\n",
2641 fsg_num_buffers, 2, 4);
2645 struct fsg_common *fsg_common_init(struct fsg_common *common,
2646 struct usb_composite_dev *cdev,
2647 struct fsg_config *cfg)
2649 struct usb_gadget *gadget = cdev->gadget;
2650 struct fsg_buffhd *bh;
2651 struct fsg_lun **curlun_it;
2652 struct fsg_lun_config *lcfg;
2653 struct usb_string *us;
2657 rc = fsg_num_buffers_validate(cfg->fsg_num_buffers);
2661 /* Find out how many LUNs there should be */
2663 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2664 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2665 return ERR_PTR(-EINVAL);
2670 common = kzalloc(sizeof *common, GFP_KERNEL);
2672 return ERR_PTR(-ENOMEM);
2673 common->free_storage_on_release = 1;
2675 memset(common, 0, sizeof *common);
2676 common->free_storage_on_release = 0;
2679 common->fsg_num_buffers = cfg->fsg_num_buffers;
2680 common->buffhds = kcalloc(common->fsg_num_buffers,
2681 sizeof *(common->buffhds), GFP_KERNEL);
2682 if (!common->buffhds) {
2683 if (common->free_storage_on_release)
2685 return ERR_PTR(-ENOMEM);
2688 common->ops = cfg->ops;
2689 common->private_data = cfg->private_data;
2691 common->gadget = gadget;
2692 common->ep0 = gadget->ep0;
2693 common->ep0req = cdev->req;
2694 common->cdev = cdev;
2696 us = usb_gstrings_attach(cdev, fsg_strings_array,
2697 ARRAY_SIZE(fsg_strings));
2702 fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
2705 * Create the LUNs, open their backing files, and register the
2706 * LUN devices in sysfs.
2708 curlun_it = kcalloc(nluns, sizeof(*curlun_it), GFP_KERNEL);
2709 if (unlikely(!curlun_it)) {
2713 common->luns = curlun_it;
2715 init_rwsem(&common->filesem);
2717 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun_it, ++lcfg) {
2718 struct fsg_lun *curlun;
2720 curlun = kzalloc(sizeof(*curlun), GFP_KERNEL);
2726 *curlun_it = curlun;
2728 curlun->cdrom = !!lcfg->cdrom;
2729 curlun->ro = lcfg->cdrom || lcfg->ro;
2730 curlun->initially_ro = curlun->ro;
2731 curlun->removable = lcfg->removable;
2732 curlun->dev.release = fsg_lun_release;
2733 curlun->dev.parent = &gadget->dev;
2734 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2735 dev_set_drvdata(&curlun->dev, &common->filesem);
2736 dev_set_name(&curlun->dev, "lun%d", i);
2738 rc = device_register(&curlun->dev);
2740 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2742 put_device(&curlun->dev);
2747 rc = device_create_file(&curlun->dev,
2749 ? &dev_attr_ro_cdrom
2753 rc = device_create_file(&curlun->dev,
2756 : &dev_attr_file_nonremovable);
2759 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2763 if (lcfg->filename) {
2764 rc = fsg_lun_open(curlun, lcfg->filename);
2767 } else if (!curlun->removable) {
2768 ERROR(common, "no file given for LUN%d\n", i);
2773 common->nluns = nluns;
2775 /* Data buffers cyclic list */
2776 bh = common->buffhds;
2777 i = common->fsg_num_buffers;
2778 goto buffhds_first_it;
2783 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2784 if (unlikely(!bh->buf)) {
2789 bh->next = common->buffhds;
2791 /* Prepare inquiryString */
2792 i = get_default_bcdDevice();
2793 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2794 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2795 /* Assume product name dependent on the first LUN */
2796 cfg->product_name ?: ((*common->luns)->cdrom
2798 : "File-Stor Gadget"),
2802 * Some peripheral controllers are known not to be able to
2803 * halt bulk endpoints correctly. If one of them is present,
2806 common->can_stall = cfg->can_stall &&
2807 !(gadget_is_at91(common->gadget));
2809 spin_lock_init(&common->lock);
2810 kref_init(&common->ref);
2812 /* Tell the thread to start working */
2813 common->thread_task =
2814 kthread_create(fsg_main_thread, common, "file-storage");
2815 if (IS_ERR(common->thread_task)) {
2816 rc = PTR_ERR(common->thread_task);
2819 init_completion(&common->thread_notifier);
2820 init_waitqueue_head(&common->fsg_wait);
2823 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2824 INFO(common, "Number of LUNs=%d\n", common->nluns);
2826 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2827 for (i = 0, nluns = common->nluns, curlun_it = common->luns;
2830 struct fsg_lun *curlun = *curlun_it;
2831 char *p = "(no medium)";
2832 if (fsg_lun_is_open(curlun)) {
2835 p = d_path(&curlun->filp->f_path,
2841 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2842 curlun->removable ? "removable " : "",
2843 curlun->ro ? "read only " : "",
2844 curlun->cdrom ? "CD-ROM " : "",
2849 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2851 wake_up_process(common->thread_task);
2856 common->nluns = i + 1;
2858 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2859 /* Call fsg_common_release() directly, ref might be not initialised. */
2860 fsg_common_release(&common->ref);
2864 static void fsg_common_release(struct kref *ref)
2866 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2868 /* If the thread isn't already dead, tell it to exit now */
2869 if (common->state != FSG_STATE_TERMINATED) {
2870 raise_exception(common, FSG_STATE_EXIT);
2871 wait_for_completion(&common->thread_notifier);
2874 if (likely(common->luns)) {
2875 struct fsg_lun **lun_it = common->luns;
2876 unsigned i = common->nluns;
2878 /* In error recovery common->nluns may be zero. */
2879 for (; i; --i, ++lun_it) {
2880 struct fsg_lun *lun = *lun_it;
2883 device_remove_file(&lun->dev, &dev_attr_nofua);
2884 device_remove_file(&lun->dev,
2886 ? &dev_attr_ro_cdrom
2888 device_remove_file(&lun->dev,
2891 : &dev_attr_file_nonremovable);
2893 device_unregister(&lun->dev);
2897 kfree(common->luns);
2901 struct fsg_buffhd *bh = common->buffhds;
2902 unsigned i = common->fsg_num_buffers;
2905 } while (++bh, --i);
2908 kfree(common->buffhds);
2909 if (common->free_storage_on_release)
2914 /*-------------------------------------------------------------------------*/
2916 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2918 struct fsg_dev *fsg = fsg_from_func(f);
2919 struct fsg_common *common = fsg->common;
2921 DBG(fsg, "unbind\n");
2922 if (fsg->common->fsg == fsg) {
2923 fsg->common->new_fsg = NULL;
2924 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2925 /* FIXME: make interruptible or killable somehow? */
2926 wait_event(common->fsg_wait, common->fsg != fsg);
2929 fsg_common_put(common);
2930 usb_free_all_descriptors(&fsg->function);
2934 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2936 struct fsg_dev *fsg = fsg_from_func(f);
2937 struct usb_gadget *gadget = c->cdev->gadget;
2943 fsg->gadget = gadget;
2946 i = usb_interface_id(c, f);
2949 fsg_intf_desc.bInterfaceNumber = i;
2950 fsg->interface_number = i;
2952 /* Find all the endpoints we will use */
2953 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2956 ep->driver_data = fsg->common; /* claim the endpoint */
2959 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2962 ep->driver_data = fsg->common; /* claim the endpoint */
2965 /* Assume endpoint addresses are the same for both speeds */
2966 fsg_hs_bulk_in_desc.bEndpointAddress =
2967 fsg_fs_bulk_in_desc.bEndpointAddress;
2968 fsg_hs_bulk_out_desc.bEndpointAddress =
2969 fsg_fs_bulk_out_desc.bEndpointAddress;
2971 /* Calculate bMaxBurst, we know packet size is 1024 */
2972 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
2974 fsg_ss_bulk_in_desc.bEndpointAddress =
2975 fsg_fs_bulk_in_desc.bEndpointAddress;
2976 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
2978 fsg_ss_bulk_out_desc.bEndpointAddress =
2979 fsg_fs_bulk_out_desc.bEndpointAddress;
2980 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
2982 ret = usb_assign_descriptors(f, fsg_fs_function, fsg_hs_function,
2990 ERROR(fsg, "unable to autoconfigure all endpoints\n");
2994 /****************************** ADD FUNCTION ******************************/
2996 static int fsg_bind_config(struct usb_composite_dev *cdev,
2997 struct usb_configuration *c,
2998 struct fsg_common *common)
3000 struct fsg_dev *fsg;
3003 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3007 fsg->function.name = FSG_DRIVER_DESC;
3008 fsg->function.bind = fsg_bind;
3009 fsg->function.unbind = fsg_unbind;
3010 fsg->function.setup = fsg_setup;
3011 fsg->function.set_alt = fsg_set_alt;
3012 fsg->function.disable = fsg_disable;
3014 fsg->common = common;
3016 * Our caller holds a reference to common structure so we
3017 * don't have to be worry about it being freed until we return
3018 * from this function. So instead of incrementing counter now
3019 * and decrement in error recovery we increment it only when
3020 * call to usb_add_function() was successful.
3023 rc = usb_add_function(c, &fsg->function);
3027 fsg_common_get(fsg->common);
3032 /************************* Module parameters *************************/
3035 void fsg_config_from_params(struct fsg_config *cfg,
3036 const struct fsg_module_parameters *params,
3037 unsigned int fsg_num_buffers)
3039 struct fsg_lun_config *lun;
3042 /* Configure LUNs */
3044 min(params->luns ?: (params->file_count ?: 1u),
3045 (unsigned)FSG_MAX_LUNS);
3046 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3047 lun->ro = !!params->ro[i];
3048 lun->cdrom = !!params->cdrom[i];
3049 lun->removable = !!params->removable[i];
3051 params->file_count > i && params->file[i][0]
3056 /* Let MSF use defaults */
3057 cfg->vendor_name = NULL;
3058 cfg->product_name = NULL;
3061 cfg->private_data = NULL;
3064 cfg->can_stall = params->stall;
3065 cfg->fsg_num_buffers = fsg_num_buffers;