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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17 * documentation and/or other materials provided with the distribution.
18 * 3. The names of the above-listed copyright holders may not be used
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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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33 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 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/utsname.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 static const char fsg_string_interface[] = "Mass Storage";
232 #define FSG_NO_DEVICE_STRINGS 1
234 #define FSG_NO_INTR_EP 1
236 #include "storage_common.c"
239 /*-------------------------------------------------------------------------*/
244 /* FSF callback functions */
245 struct fsg_operations {
247 * Callback function to call when thread exits. If no
248 * callback is set or it returns value lower then zero MSF
249 * will force eject all LUNs it operates on (including those
250 * marked as non-removable or with prevent_medium_removal flag
253 int (*thread_exits)(struct fsg_common *common);
256 * Called prior to ejection. Negative return means error,
257 * zero means to continue with ejection, positive means not to
260 int (*pre_eject)(struct fsg_common *common,
261 struct fsg_lun *lun, int num);
263 * Called after ejection. Negative return means error, zero
264 * or positive is just a success.
266 int (*post_eject)(struct fsg_common *common,
267 struct fsg_lun *lun, int num);
270 /* Data shared by all the FSG instances. */
272 struct usb_gadget *gadget;
273 struct usb_composite_dev *cdev;
274 struct fsg_dev *fsg, *new_fsg;
275 wait_queue_head_t fsg_wait;
277 /* filesem protects: backing files in use */
278 struct rw_semaphore filesem;
280 /* lock protects: state, all the req_busy's */
283 struct usb_ep *ep0; /* Copy of gadget->ep0 */
284 struct usb_request *ep0req; /* Copy of cdev->req */
285 unsigned int ep0_req_tag;
287 struct fsg_buffhd *next_buffhd_to_fill;
288 struct fsg_buffhd *next_buffhd_to_drain;
289 struct fsg_buffhd *buffhds;
292 u8 cmnd[MAX_COMMAND_SIZE];
296 struct fsg_lun *luns;
297 struct fsg_lun *curlun;
299 unsigned int bulk_out_maxpacket;
300 enum fsg_state state; /* For exception handling */
301 unsigned int exception_req_tag;
303 enum data_direction data_dir;
305 u32 data_size_from_cmnd;
310 unsigned int can_stall:1;
311 unsigned int free_storage_on_release:1;
312 unsigned int phase_error:1;
313 unsigned int short_packet_received:1;
314 unsigned int bad_lun_okay:1;
315 unsigned int running:1;
317 int thread_wakeup_needed;
318 struct completion thread_notifier;
319 struct task_struct *thread_task;
321 /* Callback functions. */
322 const struct fsg_operations *ops;
323 /* Gadget's private data. */
327 * Vendor (8 chars), product (16 chars), release (4
328 * hexadecimal digits) and NUL byte
330 char inquiry_string[8 + 16 + 4 + 1];
337 struct fsg_lun_config {
338 const char *filename;
343 } luns[FSG_MAX_LUNS];
345 /* Callback functions. */
346 const struct fsg_operations *ops;
347 /* Gadget's private data. */
350 const char *vendor_name; /* 8 characters or less */
351 const char *product_name; /* 16 characters or less */
358 struct usb_function function;
359 struct usb_gadget *gadget; /* Copy of cdev->gadget */
360 struct fsg_common *common;
362 u16 interface_number;
364 unsigned int bulk_in_enabled:1;
365 unsigned int bulk_out_enabled:1;
367 unsigned long atomic_bitflags;
368 #define IGNORE_BULK_OUT 0
370 struct usb_ep *bulk_in;
371 struct usb_ep *bulk_out;
374 static inline int __fsg_is_set(struct fsg_common *common,
375 const char *func, unsigned line)
379 ERROR(common, "common->fsg is NULL in %s at %u\n", func, line);
384 #define fsg_is_set(common) likely(__fsg_is_set(common, __func__, __LINE__))
386 static inline struct fsg_dev *fsg_from_func(struct usb_function *f)
388 return container_of(f, struct fsg_dev, function);
391 typedef void (*fsg_routine_t)(struct fsg_dev *);
393 static int exception_in_progress(struct fsg_common *common)
395 return common->state > FSG_STATE_IDLE;
398 /* Make bulk-out requests be divisible by the maxpacket size */
399 static void set_bulk_out_req_length(struct fsg_common *common,
400 struct fsg_buffhd *bh, unsigned int length)
404 bh->bulk_out_intended_length = length;
405 rem = length % common->bulk_out_maxpacket;
407 length += common->bulk_out_maxpacket - rem;
408 bh->outreq->length = length;
412 /*-------------------------------------------------------------------------*/
414 static int fsg_set_halt(struct fsg_dev *fsg, struct usb_ep *ep)
418 if (ep == fsg->bulk_in)
420 else if (ep == fsg->bulk_out)
424 DBG(fsg, "%s set halt\n", name);
425 return usb_ep_set_halt(ep);
429 /*-------------------------------------------------------------------------*/
431 /* These routines may be called in process context or in_irq */
433 /* Caller must hold fsg->lock */
434 static void wakeup_thread(struct fsg_common *common)
436 /* Tell the main thread that something has happened */
437 common->thread_wakeup_needed = 1;
438 if (common->thread_task)
439 wake_up_process(common->thread_task);
442 static void raise_exception(struct fsg_common *common, enum fsg_state new_state)
447 * Do nothing if a higher-priority exception is already in progress.
448 * If a lower-or-equal priority exception is in progress, preempt it
449 * and notify the main thread by sending it a signal.
451 spin_lock_irqsave(&common->lock, flags);
452 if (common->state <= new_state) {
453 common->exception_req_tag = common->ep0_req_tag;
454 common->state = new_state;
455 if (common->thread_task)
456 send_sig_info(SIGUSR1, SEND_SIG_FORCED,
457 common->thread_task);
459 spin_unlock_irqrestore(&common->lock, flags);
463 /*-------------------------------------------------------------------------*/
465 static int ep0_queue(struct fsg_common *common)
469 rc = usb_ep_queue(common->ep0, common->ep0req, GFP_ATOMIC);
470 common->ep0->driver_data = common;
471 if (rc != 0 && rc != -ESHUTDOWN) {
472 /* We can't do much more than wait for a reset */
473 WARNING(common, "error in submission: %s --> %d\n",
474 common->ep0->name, rc);
480 /*-------------------------------------------------------------------------*/
482 /* Completion handlers. These always run in_irq. */
484 static void bulk_in_complete(struct usb_ep *ep, struct usb_request *req)
486 struct fsg_common *common = ep->driver_data;
487 struct fsg_buffhd *bh = req->context;
489 if (req->status || req->actual != req->length)
490 DBG(common, "%s --> %d, %u/%u\n", __func__,
491 req->status, req->actual, req->length);
492 if (req->status == -ECONNRESET) /* Request was cancelled */
493 usb_ep_fifo_flush(ep);
495 /* Hold the lock while we update the request and buffer states */
497 spin_lock(&common->lock);
499 bh->state = BUF_STATE_EMPTY;
500 wakeup_thread(common);
501 spin_unlock(&common->lock);
504 static void bulk_out_complete(struct usb_ep *ep, struct usb_request *req)
506 struct fsg_common *common = ep->driver_data;
507 struct fsg_buffhd *bh = req->context;
509 dump_msg(common, "bulk-out", req->buf, req->actual);
510 if (req->status || req->actual != bh->bulk_out_intended_length)
511 DBG(common, "%s --> %d, %u/%u\n", __func__,
512 req->status, req->actual, bh->bulk_out_intended_length);
513 if (req->status == -ECONNRESET) /* Request was cancelled */
514 usb_ep_fifo_flush(ep);
516 /* Hold the lock while we update the request and buffer states */
518 spin_lock(&common->lock);
520 bh->state = BUF_STATE_FULL;
521 wakeup_thread(common);
522 spin_unlock(&common->lock);
525 static int fsg_setup(struct usb_function *f,
526 const struct usb_ctrlrequest *ctrl)
528 struct fsg_dev *fsg = fsg_from_func(f);
529 struct usb_request *req = fsg->common->ep0req;
530 u16 w_index = le16_to_cpu(ctrl->wIndex);
531 u16 w_value = le16_to_cpu(ctrl->wValue);
532 u16 w_length = le16_to_cpu(ctrl->wLength);
534 if (!fsg_is_set(fsg->common))
537 ++fsg->common->ep0_req_tag; /* Record arrival of a new request */
540 dump_msg(fsg, "ep0-setup", (u8 *) ctrl, sizeof(*ctrl));
542 switch (ctrl->bRequest) {
544 case US_BULK_RESET_REQUEST:
545 if (ctrl->bRequestType !=
546 (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
548 if (w_index != fsg->interface_number || w_value != 0 ||
553 * Raise an exception to stop the current operation
554 * and reinitialize our state.
556 DBG(fsg, "bulk reset request\n");
557 raise_exception(fsg->common, FSG_STATE_RESET);
558 return DELAYED_STATUS;
560 case US_BULK_GET_MAX_LUN:
561 if (ctrl->bRequestType !=
562 (USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
564 if (w_index != fsg->interface_number || w_value != 0 ||
567 VDBG(fsg, "get max LUN\n");
568 *(u8 *)req->buf = fsg->common->nluns - 1;
570 /* Respond with data/status */
571 req->length = min((u16)1, w_length);
572 return ep0_queue(fsg->common);
576 "unknown class-specific control req %02x.%02x v%04x i%04x l%u\n",
577 ctrl->bRequestType, ctrl->bRequest,
578 le16_to_cpu(ctrl->wValue), w_index, w_length);
583 /*-------------------------------------------------------------------------*/
585 /* All the following routines run in process context */
587 /* Use this for bulk or interrupt transfers, not ep0 */
588 static void start_transfer(struct fsg_dev *fsg, struct usb_ep *ep,
589 struct usb_request *req, int *pbusy,
590 enum fsg_buffer_state *state)
594 if (ep == fsg->bulk_in)
595 dump_msg(fsg, "bulk-in", req->buf, req->length);
597 spin_lock_irq(&fsg->common->lock);
599 *state = BUF_STATE_BUSY;
600 spin_unlock_irq(&fsg->common->lock);
601 rc = usb_ep_queue(ep, req, GFP_KERNEL);
604 *state = BUF_STATE_EMPTY;
606 /* We can't do much more than wait for a reset */
609 * Note: currently the net2280 driver fails zero-length
610 * submissions if DMA is enabled.
612 if (rc != -ESHUTDOWN &&
613 !(rc == -EOPNOTSUPP && req->length == 0))
614 WARNING(fsg, "error in submission: %s --> %d\n",
619 static bool start_in_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
621 if (!fsg_is_set(common))
623 start_transfer(common->fsg, common->fsg->bulk_in,
624 bh->inreq, &bh->inreq_busy, &bh->state);
628 static bool start_out_transfer(struct fsg_common *common, struct fsg_buffhd *bh)
630 if (!fsg_is_set(common))
632 start_transfer(common->fsg, common->fsg->bulk_out,
633 bh->outreq, &bh->outreq_busy, &bh->state);
637 static int sleep_thread(struct fsg_common *common)
641 /* Wait until a signal arrives or we are woken up */
644 set_current_state(TASK_INTERRUPTIBLE);
645 if (signal_pending(current)) {
649 if (common->thread_wakeup_needed)
653 __set_current_state(TASK_RUNNING);
654 common->thread_wakeup_needed = 0;
659 /*-------------------------------------------------------------------------*/
661 static int do_read(struct fsg_common *common)
663 struct fsg_lun *curlun = common->curlun;
665 struct fsg_buffhd *bh;
668 loff_t file_offset, file_offset_tmp;
673 * Get the starting Logical Block Address and check that it's
676 if (common->cmnd[0] == READ_6)
677 lba = get_unaligned_be24(&common->cmnd[1]);
679 lba = get_unaligned_be32(&common->cmnd[2]);
682 * We allow DPO (Disable Page Out = don't save data in the
683 * cache) and FUA (Force Unit Access = don't read from the
684 * cache), but we don't implement them.
686 if ((common->cmnd[1] & ~0x18) != 0) {
687 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
691 if (lba >= curlun->num_sectors) {
692 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
695 file_offset = ((loff_t) lba) << curlun->blkbits;
697 /* Carry out the file reads */
698 amount_left = common->data_size_from_cmnd;
699 if (unlikely(amount_left == 0))
700 return -EIO; /* No default reply */
704 * Figure out how much we need to read:
705 * Try to read the remaining amount.
706 * But don't read more than the buffer size.
707 * And don't try to read past the end of the file.
709 amount = min(amount_left, FSG_BUFLEN);
710 amount = min((loff_t)amount,
711 curlun->file_length - file_offset);
713 /* Wait for the next buffer to become available */
714 bh = common->next_buffhd_to_fill;
715 while (bh->state != BUF_STATE_EMPTY) {
716 rc = sleep_thread(common);
722 * If we were asked to read past the end of file,
723 * end with an empty buffer.
727 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
728 curlun->sense_data_info =
729 file_offset >> curlun->blkbits;
730 curlun->info_valid = 1;
731 bh->inreq->length = 0;
732 bh->state = BUF_STATE_FULL;
736 /* Perform the read */
737 file_offset_tmp = file_offset;
738 nread = vfs_read(curlun->filp,
739 (char __user *)bh->buf,
740 amount, &file_offset_tmp);
741 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
742 (unsigned long long)file_offset, (int)nread);
743 if (signal_pending(current))
747 LDBG(curlun, "error in file read: %d\n", (int)nread);
749 } else if (nread < amount) {
750 LDBG(curlun, "partial file read: %d/%u\n",
752 nread = round_down(nread, curlun->blksize);
754 file_offset += nread;
755 amount_left -= nread;
756 common->residue -= nread;
759 * Except at the end of the transfer, nread will be
760 * equal to the buffer size, which is divisible by the
761 * bulk-in maxpacket size.
763 bh->inreq->length = nread;
764 bh->state = BUF_STATE_FULL;
766 /* If an error occurred, report it and its position */
767 if (nread < amount) {
768 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
769 curlun->sense_data_info =
770 file_offset >> curlun->blkbits;
771 curlun->info_valid = 1;
775 if (amount_left == 0)
776 break; /* No more left to read */
778 /* Send this buffer and go read some more */
780 if (!start_in_transfer(common, bh))
781 /* Don't know what to do if common->fsg is NULL */
783 common->next_buffhd_to_fill = bh->next;
786 return -EIO; /* No default reply */
790 /*-------------------------------------------------------------------------*/
792 static int do_write(struct fsg_common *common)
794 struct fsg_lun *curlun = common->curlun;
796 struct fsg_buffhd *bh;
798 u32 amount_left_to_req, amount_left_to_write;
799 loff_t usb_offset, file_offset, file_offset_tmp;
805 curlun->sense_data = SS_WRITE_PROTECTED;
808 spin_lock(&curlun->filp->f_lock);
809 curlun->filp->f_flags &= ~O_SYNC; /* Default is not to wait */
810 spin_unlock(&curlun->filp->f_lock);
813 * Get the starting Logical Block Address and check that it's
816 if (common->cmnd[0] == WRITE_6)
817 lba = get_unaligned_be24(&common->cmnd[1]);
819 lba = get_unaligned_be32(&common->cmnd[2]);
822 * We allow DPO (Disable Page Out = don't save data in the
823 * cache) and FUA (Force Unit Access = write directly to the
824 * medium). We don't implement DPO; we implement FUA by
825 * performing synchronous output.
827 if (common->cmnd[1] & ~0x18) {
828 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
831 if (!curlun->nofua && (common->cmnd[1] & 0x08)) { /* FUA */
832 spin_lock(&curlun->filp->f_lock);
833 curlun->filp->f_flags |= O_SYNC;
834 spin_unlock(&curlun->filp->f_lock);
837 if (lba >= curlun->num_sectors) {
838 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
842 /* Carry out the file writes */
844 file_offset = usb_offset = ((loff_t) lba) << curlun->blkbits;
845 amount_left_to_req = common->data_size_from_cmnd;
846 amount_left_to_write = common->data_size_from_cmnd;
848 while (amount_left_to_write > 0) {
850 /* Queue a request for more data from the host */
851 bh = common->next_buffhd_to_fill;
852 if (bh->state == BUF_STATE_EMPTY && get_some_more) {
855 * Figure out how much we want to get:
856 * Try to get the remaining amount,
857 * but not more than the buffer size.
859 amount = min(amount_left_to_req, FSG_BUFLEN);
861 /* Beyond the end of the backing file? */
862 if (usb_offset >= curlun->file_length) {
865 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
866 curlun->sense_data_info =
867 usb_offset >> curlun->blkbits;
868 curlun->info_valid = 1;
872 /* Get the next buffer */
873 usb_offset += amount;
874 common->usb_amount_left -= amount;
875 amount_left_to_req -= amount;
876 if (amount_left_to_req == 0)
880 * Except at the end of the transfer, amount will be
881 * equal to the buffer size, which is divisible by
882 * the bulk-out maxpacket size.
884 set_bulk_out_req_length(common, bh, amount);
885 if (!start_out_transfer(common, bh))
886 /* Dunno what to do if common->fsg is NULL */
888 common->next_buffhd_to_fill = bh->next;
892 /* Write the received data to the backing file */
893 bh = common->next_buffhd_to_drain;
894 if (bh->state == BUF_STATE_EMPTY && !get_some_more)
895 break; /* We stopped early */
896 if (bh->state == BUF_STATE_FULL) {
898 common->next_buffhd_to_drain = bh->next;
899 bh->state = BUF_STATE_EMPTY;
901 /* Did something go wrong with the transfer? */
902 if (bh->outreq->status != 0) {
903 curlun->sense_data = SS_COMMUNICATION_FAILURE;
904 curlun->sense_data_info =
905 file_offset >> curlun->blkbits;
906 curlun->info_valid = 1;
910 amount = bh->outreq->actual;
911 if (curlun->file_length - file_offset < amount) {
913 "write %u @ %llu beyond end %llu\n",
914 amount, (unsigned long long)file_offset,
915 (unsigned long long)curlun->file_length);
916 amount = curlun->file_length - file_offset;
919 /* Don't accept excess data. The spec doesn't say
920 * what to do in this case. We'll ignore the error.
922 amount = min(amount, bh->bulk_out_intended_length);
924 /* Don't write a partial block */
925 amount = round_down(amount, curlun->blksize);
929 /* Perform the write */
930 file_offset_tmp = file_offset;
931 nwritten = vfs_write(curlun->filp,
932 (char __user *)bh->buf,
933 amount, &file_offset_tmp);
934 VLDBG(curlun, "file write %u @ %llu -> %d\n", amount,
935 (unsigned long long)file_offset, (int)nwritten);
936 if (signal_pending(current))
937 return -EINTR; /* Interrupted! */
940 LDBG(curlun, "error in file write: %d\n",
943 } else if (nwritten < amount) {
944 LDBG(curlun, "partial file write: %d/%u\n",
945 (int)nwritten, amount);
946 nwritten = round_down(nwritten, curlun->blksize);
948 file_offset += nwritten;
949 amount_left_to_write -= nwritten;
950 common->residue -= nwritten;
952 /* If an error occurred, report it and its position */
953 if (nwritten < amount) {
954 curlun->sense_data = SS_WRITE_ERROR;
955 curlun->sense_data_info =
956 file_offset >> curlun->blkbits;
957 curlun->info_valid = 1;
962 /* Did the host decide to stop early? */
963 if (bh->outreq->actual < bh->bulk_out_intended_length) {
964 common->short_packet_received = 1;
970 /* Wait for something to happen */
971 rc = sleep_thread(common);
976 return -EIO; /* No default reply */
980 /*-------------------------------------------------------------------------*/
982 static int do_synchronize_cache(struct fsg_common *common)
984 struct fsg_lun *curlun = common->curlun;
987 /* We ignore the requested LBA and write out all file's
988 * dirty data buffers. */
989 rc = fsg_lun_fsync_sub(curlun);
991 curlun->sense_data = SS_WRITE_ERROR;
996 /*-------------------------------------------------------------------------*/
998 static void invalidate_sub(struct fsg_lun *curlun)
1000 struct file *filp = curlun->filp;
1001 struct inode *inode = filp->f_path.dentry->d_inode;
1004 rc = invalidate_mapping_pages(inode->i_mapping, 0, -1);
1005 VLDBG(curlun, "invalidate_mapping_pages -> %ld\n", rc);
1008 static int do_verify(struct fsg_common *common)
1010 struct fsg_lun *curlun = common->curlun;
1012 u32 verification_length;
1013 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1014 loff_t file_offset, file_offset_tmp;
1016 unsigned int amount;
1020 * Get the starting Logical Block Address and check that it's
1023 lba = get_unaligned_be32(&common->cmnd[2]);
1024 if (lba >= curlun->num_sectors) {
1025 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1030 * We allow DPO (Disable Page Out = don't save data in the
1031 * cache) but we don't implement it.
1033 if (common->cmnd[1] & ~0x10) {
1034 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1038 verification_length = get_unaligned_be16(&common->cmnd[7]);
1039 if (unlikely(verification_length == 0))
1040 return -EIO; /* No default reply */
1042 /* Prepare to carry out the file verify */
1043 amount_left = verification_length << curlun->blkbits;
1044 file_offset = ((loff_t) lba) << curlun->blkbits;
1046 /* Write out all the dirty buffers before invalidating them */
1047 fsg_lun_fsync_sub(curlun);
1048 if (signal_pending(current))
1051 invalidate_sub(curlun);
1052 if (signal_pending(current))
1055 /* Just try to read the requested blocks */
1056 while (amount_left > 0) {
1058 * Figure out how much we need to read:
1059 * Try to read the remaining amount, but not more than
1061 * And don't try to read past the end of the file.
1063 amount = min(amount_left, FSG_BUFLEN);
1064 amount = min((loff_t)amount,
1065 curlun->file_length - file_offset);
1067 curlun->sense_data =
1068 SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1069 curlun->sense_data_info =
1070 file_offset >> curlun->blkbits;
1071 curlun->info_valid = 1;
1075 /* Perform the read */
1076 file_offset_tmp = file_offset;
1077 nread = vfs_read(curlun->filp,
1078 (char __user *) bh->buf,
1079 amount, &file_offset_tmp);
1080 VLDBG(curlun, "file read %u @ %llu -> %d\n", amount,
1081 (unsigned long long) file_offset,
1083 if (signal_pending(current))
1087 LDBG(curlun, "error in file verify: %d\n", (int)nread);
1089 } else if (nread < amount) {
1090 LDBG(curlun, "partial file verify: %d/%u\n",
1091 (int)nread, amount);
1092 nread = round_down(nread, curlun->blksize);
1095 curlun->sense_data = SS_UNRECOVERED_READ_ERROR;
1096 curlun->sense_data_info =
1097 file_offset >> curlun->blkbits;
1098 curlun->info_valid = 1;
1101 file_offset += nread;
1102 amount_left -= nread;
1108 /*-------------------------------------------------------------------------*/
1110 static int do_inquiry(struct fsg_common *common, struct fsg_buffhd *bh)
1112 struct fsg_lun *curlun = common->curlun;
1113 u8 *buf = (u8 *) bh->buf;
1115 if (!curlun) { /* Unsupported LUNs are okay */
1116 common->bad_lun_okay = 1;
1118 buf[0] = 0x7f; /* Unsupported, no device-type */
1119 buf[4] = 31; /* Additional length */
1123 buf[0] = curlun->cdrom ? TYPE_ROM : TYPE_DISK;
1124 buf[1] = curlun->removable ? 0x80 : 0;
1125 buf[2] = 2; /* ANSI SCSI level 2 */
1126 buf[3] = 2; /* SCSI-2 INQUIRY data format */
1127 buf[4] = 31; /* Additional length */
1128 buf[5] = 0; /* No special options */
1131 memcpy(buf + 8, common->inquiry_string, sizeof common->inquiry_string);
1135 static int do_request_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1137 struct fsg_lun *curlun = common->curlun;
1138 u8 *buf = (u8 *) bh->buf;
1143 * From the SCSI-2 spec., section 7.9 (Unit attention condition):
1145 * If a REQUEST SENSE command is received from an initiator
1146 * with a pending unit attention condition (before the target
1147 * generates the contingent allegiance condition), then the
1148 * target shall either:
1149 * a) report any pending sense data and preserve the unit
1150 * attention condition on the logical unit, or,
1151 * b) report the unit attention condition, may discard any
1152 * pending sense data, and clear the unit attention
1153 * condition on the logical unit for that initiator.
1155 * FSG normally uses option a); enable this code to use option b).
1158 if (curlun && curlun->unit_attention_data != SS_NO_SENSE) {
1159 curlun->sense_data = curlun->unit_attention_data;
1160 curlun->unit_attention_data = SS_NO_SENSE;
1164 if (!curlun) { /* Unsupported LUNs are okay */
1165 common->bad_lun_okay = 1;
1166 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1170 sd = curlun->sense_data;
1171 sdinfo = curlun->sense_data_info;
1172 valid = curlun->info_valid << 7;
1173 curlun->sense_data = SS_NO_SENSE;
1174 curlun->sense_data_info = 0;
1175 curlun->info_valid = 0;
1179 buf[0] = valid | 0x70; /* Valid, current error */
1181 put_unaligned_be32(sdinfo, &buf[3]); /* Sense information */
1182 buf[7] = 18 - 8; /* Additional sense length */
1188 static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh)
1190 struct fsg_lun *curlun = common->curlun;
1191 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1192 int pmi = common->cmnd[8];
1193 u8 *buf = (u8 *)bh->buf;
1195 /* Check the PMI and LBA fields */
1196 if (pmi > 1 || (pmi == 0 && lba != 0)) {
1197 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1201 put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);
1202 /* Max logical block */
1203 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1207 static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)
1209 struct fsg_lun *curlun = common->curlun;
1210 int msf = common->cmnd[1] & 0x02;
1211 u32 lba = get_unaligned_be32(&common->cmnd[2]);
1212 u8 *buf = (u8 *)bh->buf;
1214 if (common->cmnd[1] & ~0x02) { /* Mask away MSF */
1215 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1218 if (lba >= curlun->num_sectors) {
1219 curlun->sense_data = SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE;
1224 buf[0] = 0x01; /* 2048 bytes of user data, rest is EC */
1225 store_cdrom_address(&buf[4], msf, lba);
1229 static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh)
1231 struct fsg_lun *curlun = common->curlun;
1232 int msf = common->cmnd[1] & 0x02;
1233 int start_track = common->cmnd[6];
1234 u8 *buf = (u8 *)bh->buf;
1236 if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */
1238 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1243 buf[1] = (20-2); /* TOC data length */
1244 buf[2] = 1; /* First track number */
1245 buf[3] = 1; /* Last track number */
1246 buf[5] = 0x16; /* Data track, copying allowed */
1247 buf[6] = 0x01; /* Only track is number 1 */
1248 store_cdrom_address(&buf[8], msf, 0);
1250 buf[13] = 0x16; /* Lead-out track is data */
1251 buf[14] = 0xAA; /* Lead-out track number */
1252 store_cdrom_address(&buf[16], msf, curlun->num_sectors);
1256 static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh)
1258 struct fsg_lun *curlun = common->curlun;
1259 int mscmnd = common->cmnd[0];
1260 u8 *buf = (u8 *) bh->buf;
1263 int changeable_values, all_pages;
1267 if ((common->cmnd[1] & ~0x08) != 0) { /* Mask away DBD */
1268 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1271 pc = common->cmnd[2] >> 6;
1272 page_code = common->cmnd[2] & 0x3f;
1274 curlun->sense_data = SS_SAVING_PARAMETERS_NOT_SUPPORTED;
1277 changeable_values = (pc == 1);
1278 all_pages = (page_code == 0x3f);
1281 * Write the mode parameter header. Fixed values are: default
1282 * medium type, no cache control (DPOFUA), and no block descriptors.
1283 * The only variable value is the WriteProtect bit. We will fill in
1284 * the mode data length later.
1287 if (mscmnd == MODE_SENSE) {
1288 buf[2] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1291 } else { /* MODE_SENSE_10 */
1292 buf[3] = (curlun->ro ? 0x80 : 0x00); /* WP, DPOFUA */
1294 limit = 65535; /* Should really be FSG_BUFLEN */
1297 /* No block descriptors */
1300 * The mode pages, in numerical order. The only page we support
1301 * is the Caching page.
1303 if (page_code == 0x08 || all_pages) {
1305 buf[0] = 0x08; /* Page code */
1306 buf[1] = 10; /* Page length */
1307 memset(buf+2, 0, 10); /* None of the fields are changeable */
1309 if (!changeable_values) {
1310 buf[2] = 0x04; /* Write cache enable, */
1311 /* Read cache not disabled */
1312 /* No cache retention priorities */
1313 put_unaligned_be16(0xffff, &buf[4]);
1314 /* Don't disable prefetch */
1315 /* Minimum prefetch = 0 */
1316 put_unaligned_be16(0xffff, &buf[8]);
1317 /* Maximum prefetch */
1318 put_unaligned_be16(0xffff, &buf[10]);
1319 /* Maximum prefetch ceiling */
1325 * Check that a valid page was requested and the mode data length
1329 if (!valid_page || len > limit) {
1330 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1334 /* Store the mode data length */
1335 if (mscmnd == MODE_SENSE)
1338 put_unaligned_be16(len - 2, buf0);
1342 static int do_start_stop(struct fsg_common *common)
1344 struct fsg_lun *curlun = common->curlun;
1349 } else if (!curlun->removable) {
1350 curlun->sense_data = SS_INVALID_COMMAND;
1352 } else if ((common->cmnd[1] & ~0x01) != 0 || /* Mask away Immed */
1353 (common->cmnd[4] & ~0x03) != 0) { /* Mask LoEj, Start */
1354 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1358 loej = common->cmnd[4] & 0x02;
1359 start = common->cmnd[4] & 0x01;
1362 * Our emulation doesn't support mounting; the medium is
1363 * available for use as soon as it is loaded.
1366 if (!fsg_lun_is_open(curlun)) {
1367 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1373 /* Are we allowed to unload the media? */
1374 if (curlun->prevent_medium_removal) {
1375 LDBG(curlun, "unload attempt prevented\n");
1376 curlun->sense_data = SS_MEDIUM_REMOVAL_PREVENTED;
1383 /* Simulate an unload/eject */
1384 if (common->ops && common->ops->pre_eject) {
1385 int r = common->ops->pre_eject(common, curlun,
1386 curlun - common->luns);
1387 if (unlikely(r < 0))
1393 up_read(&common->filesem);
1394 down_write(&common->filesem);
1395 fsg_lun_close(curlun);
1396 up_write(&common->filesem);
1397 down_read(&common->filesem);
1399 return common->ops && common->ops->post_eject
1400 ? min(0, common->ops->post_eject(common, curlun,
1401 curlun - common->luns))
1405 static int do_prevent_allow(struct fsg_common *common)
1407 struct fsg_lun *curlun = common->curlun;
1410 if (!common->curlun) {
1412 } else if (!common->curlun->removable) {
1413 common->curlun->sense_data = SS_INVALID_COMMAND;
1417 prevent = common->cmnd[4] & 0x01;
1418 if ((common->cmnd[4] & ~0x01) != 0) { /* Mask away Prevent */
1419 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1423 if (curlun->prevent_medium_removal && !prevent)
1424 fsg_lun_fsync_sub(curlun);
1425 curlun->prevent_medium_removal = prevent;
1429 static int do_read_format_capacities(struct fsg_common *common,
1430 struct fsg_buffhd *bh)
1432 struct fsg_lun *curlun = common->curlun;
1433 u8 *buf = (u8 *) bh->buf;
1435 buf[0] = buf[1] = buf[2] = 0;
1436 buf[3] = 8; /* Only the Current/Maximum Capacity Descriptor */
1439 put_unaligned_be32(curlun->num_sectors, &buf[0]);
1440 /* Number of blocks */
1441 put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
1442 buf[4] = 0x02; /* Current capacity */
1446 static int do_mode_select(struct fsg_common *common, struct fsg_buffhd *bh)
1448 struct fsg_lun *curlun = common->curlun;
1450 /* We don't support MODE SELECT */
1452 curlun->sense_data = SS_INVALID_COMMAND;
1457 /*-------------------------------------------------------------------------*/
1459 static int halt_bulk_in_endpoint(struct fsg_dev *fsg)
1463 rc = fsg_set_halt(fsg, fsg->bulk_in);
1465 VDBG(fsg, "delayed bulk-in endpoint halt\n");
1467 if (rc != -EAGAIN) {
1468 WARNING(fsg, "usb_ep_set_halt -> %d\n", rc);
1473 /* Wait for a short time and then try again */
1474 if (msleep_interruptible(100) != 0)
1476 rc = usb_ep_set_halt(fsg->bulk_in);
1481 static int wedge_bulk_in_endpoint(struct fsg_dev *fsg)
1485 DBG(fsg, "bulk-in set wedge\n");
1486 rc = usb_ep_set_wedge(fsg->bulk_in);
1488 VDBG(fsg, "delayed bulk-in endpoint wedge\n");
1490 if (rc != -EAGAIN) {
1491 WARNING(fsg, "usb_ep_set_wedge -> %d\n", rc);
1496 /* Wait for a short time and then try again */
1497 if (msleep_interruptible(100) != 0)
1499 rc = usb_ep_set_wedge(fsg->bulk_in);
1504 static int throw_away_data(struct fsg_common *common)
1506 struct fsg_buffhd *bh;
1510 for (bh = common->next_buffhd_to_drain;
1511 bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0;
1512 bh = common->next_buffhd_to_drain) {
1514 /* Throw away the data in a filled buffer */
1515 if (bh->state == BUF_STATE_FULL) {
1517 bh->state = BUF_STATE_EMPTY;
1518 common->next_buffhd_to_drain = bh->next;
1520 /* A short packet or an error ends everything */
1521 if (bh->outreq->actual < bh->bulk_out_intended_length ||
1522 bh->outreq->status != 0) {
1523 raise_exception(common,
1524 FSG_STATE_ABORT_BULK_OUT);
1530 /* Try to submit another request if we need one */
1531 bh = common->next_buffhd_to_fill;
1532 if (bh->state == BUF_STATE_EMPTY
1533 && common->usb_amount_left > 0) {
1534 amount = min(common->usb_amount_left, FSG_BUFLEN);
1537 * Except at the end of the transfer, amount will be
1538 * equal to the buffer size, which is divisible by
1539 * the bulk-out maxpacket size.
1541 set_bulk_out_req_length(common, bh, amount);
1542 if (!start_out_transfer(common, bh))
1543 /* Dunno what to do if common->fsg is NULL */
1545 common->next_buffhd_to_fill = bh->next;
1546 common->usb_amount_left -= amount;
1550 /* Otherwise wait for something to happen */
1551 rc = sleep_thread(common);
1558 static int finish_reply(struct fsg_common *common)
1560 struct fsg_buffhd *bh = common->next_buffhd_to_fill;
1563 switch (common->data_dir) {
1565 break; /* Nothing to send */
1568 * If we don't know whether the host wants to read or write,
1569 * this must be CB or CBI with an unknown command. We mustn't
1570 * try to send or receive any data. So stall both bulk pipes
1571 * if we can and wait for a reset.
1573 case DATA_DIR_UNKNOWN:
1574 if (!common->can_stall) {
1576 } else if (fsg_is_set(common)) {
1577 fsg_set_halt(common->fsg, common->fsg->bulk_out);
1578 rc = halt_bulk_in_endpoint(common->fsg);
1580 /* Don't know what to do if common->fsg is NULL */
1585 /* All but the last buffer of data must have already been sent */
1586 case DATA_DIR_TO_HOST:
1587 if (common->data_size == 0) {
1588 /* Nothing to send */
1590 /* Don't know what to do if common->fsg is NULL */
1591 } else if (!fsg_is_set(common)) {
1594 /* If there's no residue, simply send the last buffer */
1595 } else if (common->residue == 0) {
1596 bh->inreq->zero = 0;
1597 if (!start_in_transfer(common, bh))
1599 common->next_buffhd_to_fill = bh->next;
1602 * For Bulk-only, mark the end of the data with a short
1603 * packet. If we are allowed to stall, halt the bulk-in
1604 * endpoint. (Note: This violates the Bulk-Only Transport
1605 * specification, which requires us to pad the data if we
1606 * don't halt the endpoint. Presumably nobody will mind.)
1609 bh->inreq->zero = 1;
1610 if (!start_in_transfer(common, bh))
1612 common->next_buffhd_to_fill = bh->next;
1613 if (common->can_stall)
1614 rc = halt_bulk_in_endpoint(common->fsg);
1619 * We have processed all we want from the data the host has sent.
1620 * There may still be outstanding bulk-out requests.
1622 case DATA_DIR_FROM_HOST:
1623 if (common->residue == 0) {
1624 /* Nothing to receive */
1626 /* Did the host stop sending unexpectedly early? */
1627 } else if (common->short_packet_received) {
1628 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1632 * We haven't processed all the incoming data. Even though
1633 * we may be allowed to stall, doing so would cause a race.
1634 * The controller may already have ACK'ed all the remaining
1635 * bulk-out packets, in which case the host wouldn't see a
1636 * STALL. Not realizing the endpoint was halted, it wouldn't
1637 * clear the halt -- leading to problems later on.
1640 } else if (common->can_stall) {
1641 if (fsg_is_set(common))
1642 fsg_set_halt(common->fsg,
1643 common->fsg->bulk_out);
1644 raise_exception(common, FSG_STATE_ABORT_BULK_OUT);
1649 * We can't stall. Read in the excess data and throw it
1653 rc = throw_away_data(common);
1660 static int send_status(struct fsg_common *common)
1662 struct fsg_lun *curlun = common->curlun;
1663 struct fsg_buffhd *bh;
1664 struct bulk_cs_wrap *csw;
1666 u8 status = US_BULK_STAT_OK;
1669 /* Wait for the next buffer to become available */
1670 bh = common->next_buffhd_to_fill;
1671 while (bh->state != BUF_STATE_EMPTY) {
1672 rc = sleep_thread(common);
1678 sd = curlun->sense_data;
1679 sdinfo = curlun->sense_data_info;
1680 } else if (common->bad_lun_okay)
1683 sd = SS_LOGICAL_UNIT_NOT_SUPPORTED;
1685 if (common->phase_error) {
1686 DBG(common, "sending phase-error status\n");
1687 status = US_BULK_STAT_PHASE;
1688 sd = SS_INVALID_COMMAND;
1689 } else if (sd != SS_NO_SENSE) {
1690 DBG(common, "sending command-failure status\n");
1691 status = US_BULK_STAT_FAIL;
1692 VDBG(common, " sense data: SK x%02x, ASC x%02x, ASCQ x%02x;"
1694 SK(sd), ASC(sd), ASCQ(sd), sdinfo);
1697 /* Store and send the Bulk-only CSW */
1698 csw = (void *)bh->buf;
1700 csw->Signature = cpu_to_le32(US_BULK_CS_SIGN);
1701 csw->Tag = common->tag;
1702 csw->Residue = cpu_to_le32(common->residue);
1703 csw->Status = status;
1705 bh->inreq->length = US_BULK_CS_WRAP_LEN;
1706 bh->inreq->zero = 0;
1707 if (!start_in_transfer(common, bh))
1708 /* Don't know what to do if common->fsg is NULL */
1711 common->next_buffhd_to_fill = bh->next;
1716 /*-------------------------------------------------------------------------*/
1719 * Check whether the command is properly formed and whether its data size
1720 * and direction agree with the values we already have.
1722 static int check_command(struct fsg_common *common, int cmnd_size,
1723 enum data_direction data_dir, unsigned int mask,
1724 int needs_medium, const char *name)
1727 int lun = common->cmnd[1] >> 5;
1728 static const char dirletter[4] = {'u', 'o', 'i', 'n'};
1730 struct fsg_lun *curlun;
1733 if (common->data_dir != DATA_DIR_UNKNOWN)
1734 sprintf(hdlen, ", H%c=%u", dirletter[(int) common->data_dir],
1736 VDBG(common, "SCSI command: %s; Dc=%d, D%c=%u; Hc=%d%s\n",
1737 name, cmnd_size, dirletter[(int) data_dir],
1738 common->data_size_from_cmnd, common->cmnd_size, hdlen);
1741 * We can't reply at all until we know the correct data direction
1744 if (common->data_size_from_cmnd == 0)
1745 data_dir = DATA_DIR_NONE;
1746 if (common->data_size < common->data_size_from_cmnd) {
1748 * Host data size < Device data size is a phase error.
1749 * Carry out the command, but only transfer as much as
1752 common->data_size_from_cmnd = common->data_size;
1753 common->phase_error = 1;
1755 common->residue = common->data_size;
1756 common->usb_amount_left = common->data_size;
1758 /* Conflicting data directions is a phase error */
1759 if (common->data_dir != data_dir && common->data_size_from_cmnd > 0) {
1760 common->phase_error = 1;
1764 /* Verify the length of the command itself */
1765 if (cmnd_size != common->cmnd_size) {
1768 * Special case workaround: There are plenty of buggy SCSI
1769 * implementations. Many have issues with cbw->Length
1770 * field passing a wrong command size. For those cases we
1771 * always try to work around the problem by using the length
1772 * sent by the host side provided it is at least as large
1773 * as the correct command length.
1774 * Examples of such cases would be MS-Windows, which issues
1775 * REQUEST SENSE with cbw->Length == 12 where it should
1776 * be 6, and xbox360 issuing INQUIRY, TEST UNIT READY and
1777 * REQUEST SENSE with cbw->Length == 10 where it should
1780 if (cmnd_size <= common->cmnd_size) {
1781 DBG(common, "%s is buggy! Expected length %d "
1782 "but we got %d\n", name,
1783 cmnd_size, common->cmnd_size);
1784 cmnd_size = common->cmnd_size;
1786 common->phase_error = 1;
1791 /* Check that the LUN values are consistent */
1792 if (common->lun != lun)
1793 DBG(common, "using LUN %d from CBW, not LUN %d from CDB\n",
1797 curlun = common->curlun;
1799 if (common->cmnd[0] != REQUEST_SENSE) {
1800 curlun->sense_data = SS_NO_SENSE;
1801 curlun->sense_data_info = 0;
1802 curlun->info_valid = 0;
1805 common->bad_lun_okay = 0;
1808 * INQUIRY and REQUEST SENSE commands are explicitly allowed
1809 * to use unsupported LUNs; all others may not.
1811 if (common->cmnd[0] != INQUIRY &&
1812 common->cmnd[0] != REQUEST_SENSE) {
1813 DBG(common, "unsupported LUN %d\n", common->lun);
1819 * If a unit attention condition exists, only INQUIRY and
1820 * REQUEST SENSE commands are allowed; anything else must fail.
1822 if (curlun && curlun->unit_attention_data != SS_NO_SENSE &&
1823 common->cmnd[0] != INQUIRY &&
1824 common->cmnd[0] != REQUEST_SENSE) {
1825 curlun->sense_data = curlun->unit_attention_data;
1826 curlun->unit_attention_data = SS_NO_SENSE;
1830 /* Check that only command bytes listed in the mask are non-zero */
1831 common->cmnd[1] &= 0x1f; /* Mask away the LUN */
1832 for (i = 1; i < cmnd_size; ++i) {
1833 if (common->cmnd[i] && !(mask & (1 << i))) {
1835 curlun->sense_data = SS_INVALID_FIELD_IN_CDB;
1840 /* If the medium isn't mounted and the command needs to access
1841 * it, return an error. */
1842 if (curlun && !fsg_lun_is_open(curlun) && needs_medium) {
1843 curlun->sense_data = SS_MEDIUM_NOT_PRESENT;
1850 /* wrapper of check_command for data size in blocks handling */
1851 static int check_command_size_in_blocks(struct fsg_common *common,
1852 int cmnd_size, enum data_direction data_dir,
1853 unsigned int mask, int needs_medium, const char *name)
1856 common->data_size_from_cmnd <<= common->curlun->blkbits;
1857 return check_command(common, cmnd_size, data_dir,
1858 mask, needs_medium, name);
1861 static int do_scsi_command(struct fsg_common *common)
1863 struct fsg_buffhd *bh;
1865 int reply = -EINVAL;
1867 static char unknown[16];
1871 /* Wait for the next buffer to become available for data or status */
1872 bh = common->next_buffhd_to_fill;
1873 common->next_buffhd_to_drain = bh;
1874 while (bh->state != BUF_STATE_EMPTY) {
1875 rc = sleep_thread(common);
1879 common->phase_error = 0;
1880 common->short_packet_received = 0;
1882 down_read(&common->filesem); /* We're using the backing file */
1883 switch (common->cmnd[0]) {
1886 common->data_size_from_cmnd = common->cmnd[4];
1887 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1891 reply = do_inquiry(common, bh);
1895 common->data_size_from_cmnd = common->cmnd[4];
1896 reply = check_command(common, 6, DATA_DIR_FROM_HOST,
1900 reply = do_mode_select(common, bh);
1903 case MODE_SELECT_10:
1904 common->data_size_from_cmnd =
1905 get_unaligned_be16(&common->cmnd[7]);
1906 reply = check_command(common, 10, DATA_DIR_FROM_HOST,
1910 reply = do_mode_select(common, bh);
1914 common->data_size_from_cmnd = common->cmnd[4];
1915 reply = check_command(common, 6, DATA_DIR_TO_HOST,
1916 (1<<1) | (1<<2) | (1<<4), 0,
1919 reply = do_mode_sense(common, bh);
1923 common->data_size_from_cmnd =
1924 get_unaligned_be16(&common->cmnd[7]);
1925 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1926 (1<<1) | (1<<2) | (3<<7), 0,
1929 reply = do_mode_sense(common, bh);
1932 case ALLOW_MEDIUM_REMOVAL:
1933 common->data_size_from_cmnd = 0;
1934 reply = check_command(common, 6, DATA_DIR_NONE,
1936 "PREVENT-ALLOW MEDIUM REMOVAL");
1938 reply = do_prevent_allow(common);
1942 i = common->cmnd[4];
1943 common->data_size_from_cmnd = (i == 0) ? 256 : i;
1944 reply = check_command_size_in_blocks(common, 6,
1949 reply = do_read(common);
1953 common->data_size_from_cmnd =
1954 get_unaligned_be16(&common->cmnd[7]);
1955 reply = check_command_size_in_blocks(common, 10,
1957 (1<<1) | (0xf<<2) | (3<<7), 1,
1960 reply = do_read(common);
1964 common->data_size_from_cmnd =
1965 get_unaligned_be32(&common->cmnd[6]);
1966 reply = check_command_size_in_blocks(common, 12,
1968 (1<<1) | (0xf<<2) | (0xf<<6), 1,
1971 reply = do_read(common);
1975 common->data_size_from_cmnd = 8;
1976 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1977 (0xf<<2) | (1<<8), 1,
1980 reply = do_read_capacity(common, bh);
1984 if (!common->curlun || !common->curlun->cdrom)
1986 common->data_size_from_cmnd =
1987 get_unaligned_be16(&common->cmnd[7]);
1988 reply = check_command(common, 10, DATA_DIR_TO_HOST,
1989 (3<<7) | (0x1f<<1), 1,
1992 reply = do_read_header(common, bh);
1996 if (!common->curlun || !common->curlun->cdrom)
1998 common->data_size_from_cmnd =
1999 get_unaligned_be16(&common->cmnd[7]);
2000 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2004 reply = do_read_toc(common, bh);
2007 case READ_FORMAT_CAPACITIES:
2008 common->data_size_from_cmnd =
2009 get_unaligned_be16(&common->cmnd[7]);
2010 reply = check_command(common, 10, DATA_DIR_TO_HOST,
2012 "READ FORMAT CAPACITIES");
2014 reply = do_read_format_capacities(common, bh);
2018 common->data_size_from_cmnd = common->cmnd[4];
2019 reply = check_command(common, 6, DATA_DIR_TO_HOST,
2023 reply = do_request_sense(common, bh);
2027 common->data_size_from_cmnd = 0;
2028 reply = check_command(common, 6, DATA_DIR_NONE,
2032 reply = do_start_stop(common);
2035 case SYNCHRONIZE_CACHE:
2036 common->data_size_from_cmnd = 0;
2037 reply = check_command(common, 10, DATA_DIR_NONE,
2038 (0xf<<2) | (3<<7), 1,
2039 "SYNCHRONIZE CACHE");
2041 reply = do_synchronize_cache(common);
2044 case TEST_UNIT_READY:
2045 common->data_size_from_cmnd = 0;
2046 reply = check_command(common, 6, DATA_DIR_NONE,
2052 * Although optional, this command is used by MS-Windows. We
2053 * support a minimal version: BytChk must be 0.
2056 common->data_size_from_cmnd = 0;
2057 reply = check_command(common, 10, DATA_DIR_NONE,
2058 (1<<1) | (0xf<<2) | (3<<7), 1,
2061 reply = do_verify(common);
2065 i = common->cmnd[4];
2066 common->data_size_from_cmnd = (i == 0) ? 256 : i;
2067 reply = check_command_size_in_blocks(common, 6,
2072 reply = do_write(common);
2076 common->data_size_from_cmnd =
2077 get_unaligned_be16(&common->cmnd[7]);
2078 reply = check_command_size_in_blocks(common, 10,
2080 (1<<1) | (0xf<<2) | (3<<7), 1,
2083 reply = do_write(common);
2087 common->data_size_from_cmnd =
2088 get_unaligned_be32(&common->cmnd[6]);
2089 reply = check_command_size_in_blocks(common, 12,
2091 (1<<1) | (0xf<<2) | (0xf<<6), 1,
2094 reply = do_write(common);
2098 * Some mandatory commands that we recognize but don't implement.
2099 * They don't mean much in this setting. It's left as an exercise
2100 * for anyone interested to implement RESERVE and RELEASE in terms
2106 case SEND_DIAGNOSTIC:
2111 common->data_size_from_cmnd = 0;
2112 sprintf(unknown, "Unknown x%02x", common->cmnd[0]);
2113 reply = check_command(common, common->cmnd_size,
2114 DATA_DIR_UNKNOWN, ~0, 0, unknown);
2116 common->curlun->sense_data = SS_INVALID_COMMAND;
2121 up_read(&common->filesem);
2123 if (reply == -EINTR || signal_pending(current))
2126 /* Set up the single reply buffer for finish_reply() */
2127 if (reply == -EINVAL)
2128 reply = 0; /* Error reply length */
2129 if (reply >= 0 && common->data_dir == DATA_DIR_TO_HOST) {
2130 reply = min((u32)reply, common->data_size_from_cmnd);
2131 bh->inreq->length = reply;
2132 bh->state = BUF_STATE_FULL;
2133 common->residue -= reply;
2134 } /* Otherwise it's already set */
2140 /*-------------------------------------------------------------------------*/
2142 static int received_cbw(struct fsg_dev *fsg, struct fsg_buffhd *bh)
2144 struct usb_request *req = bh->outreq;
2145 struct bulk_cb_wrap *cbw = req->buf;
2146 struct fsg_common *common = fsg->common;
2148 /* Was this a real packet? Should it be ignored? */
2149 if (req->status || test_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags))
2152 /* Is the CBW valid? */
2153 if (req->actual != US_BULK_CB_WRAP_LEN ||
2154 cbw->Signature != cpu_to_le32(
2156 DBG(fsg, "invalid CBW: len %u sig 0x%x\n",
2158 le32_to_cpu(cbw->Signature));
2161 * The Bulk-only spec says we MUST stall the IN endpoint
2162 * (6.6.1), so it's unavoidable. It also says we must
2163 * retain this state until the next reset, but there's
2164 * no way to tell the controller driver it should ignore
2165 * Clear-Feature(HALT) requests.
2167 * We aren't required to halt the OUT endpoint; instead
2168 * we can simply accept and discard any data received
2169 * until the next reset.
2171 wedge_bulk_in_endpoint(fsg);
2172 set_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2176 /* Is the CBW meaningful? */
2177 if (cbw->Lun >= FSG_MAX_LUNS || cbw->Flags & ~US_BULK_FLAG_IN ||
2178 cbw->Length <= 0 || cbw->Length > MAX_COMMAND_SIZE) {
2179 DBG(fsg, "non-meaningful CBW: lun = %u, flags = 0x%x, "
2181 cbw->Lun, cbw->Flags, cbw->Length);
2184 * We can do anything we want here, so let's stall the
2185 * bulk pipes if we are allowed to.
2187 if (common->can_stall) {
2188 fsg_set_halt(fsg, fsg->bulk_out);
2189 halt_bulk_in_endpoint(fsg);
2194 /* Save the command for later */
2195 common->cmnd_size = cbw->Length;
2196 memcpy(common->cmnd, cbw->CDB, common->cmnd_size);
2197 if (cbw->Flags & US_BULK_FLAG_IN)
2198 common->data_dir = DATA_DIR_TO_HOST;
2200 common->data_dir = DATA_DIR_FROM_HOST;
2201 common->data_size = le32_to_cpu(cbw->DataTransferLength);
2202 if (common->data_size == 0)
2203 common->data_dir = DATA_DIR_NONE;
2204 common->lun = cbw->Lun;
2205 if (common->lun >= 0 && common->lun < common->nluns)
2206 common->curlun = &common->luns[common->lun];
2208 common->curlun = NULL;
2209 common->tag = cbw->Tag;
2213 static int get_next_command(struct fsg_common *common)
2215 struct fsg_buffhd *bh;
2218 /* Wait for the next buffer to become available */
2219 bh = common->next_buffhd_to_fill;
2220 while (bh->state != BUF_STATE_EMPTY) {
2221 rc = sleep_thread(common);
2226 /* Queue a request to read a Bulk-only CBW */
2227 set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN);
2228 if (!start_out_transfer(common, bh))
2229 /* Don't know what to do if common->fsg is NULL */
2233 * We will drain the buffer in software, which means we
2234 * can reuse it for the next filling. No need to advance
2235 * next_buffhd_to_fill.
2238 /* Wait for the CBW to arrive */
2239 while (bh->state != BUF_STATE_FULL) {
2240 rc = sleep_thread(common);
2245 rc = fsg_is_set(common) ? received_cbw(common->fsg, bh) : -EIO;
2246 bh->state = BUF_STATE_EMPTY;
2252 /*-------------------------------------------------------------------------*/
2254 static int alloc_request(struct fsg_common *common, struct usb_ep *ep,
2255 struct usb_request **preq)
2257 *preq = usb_ep_alloc_request(ep, GFP_ATOMIC);
2260 ERROR(common, "can't allocate request for %s\n", ep->name);
2264 /* Reset interface setting and re-init endpoint state (toggle etc). */
2265 static int do_set_interface(struct fsg_common *common, struct fsg_dev *new_fsg)
2267 struct fsg_dev *fsg;
2270 if (common->running)
2271 DBG(common, "reset interface\n");
2274 /* Deallocate the requests */
2278 for (i = 0; i < fsg_num_buffers; ++i) {
2279 struct fsg_buffhd *bh = &common->buffhds[i];
2282 usb_ep_free_request(fsg->bulk_in, bh->inreq);
2286 usb_ep_free_request(fsg->bulk_out, bh->outreq);
2291 /* Disable the endpoints */
2292 if (fsg->bulk_in_enabled) {
2293 usb_ep_disable(fsg->bulk_in);
2294 fsg->bulk_in_enabled = 0;
2296 if (fsg->bulk_out_enabled) {
2297 usb_ep_disable(fsg->bulk_out);
2298 fsg->bulk_out_enabled = 0;
2302 wake_up(&common->fsg_wait);
2305 common->running = 0;
2309 common->fsg = new_fsg;
2312 /* Enable the endpoints */
2313 rc = config_ep_by_speed(common->gadget, &(fsg->function), fsg->bulk_in);
2316 rc = usb_ep_enable(fsg->bulk_in);
2319 fsg->bulk_in->driver_data = common;
2320 fsg->bulk_in_enabled = 1;
2322 rc = config_ep_by_speed(common->gadget, &(fsg->function),
2326 rc = usb_ep_enable(fsg->bulk_out);
2329 fsg->bulk_out->driver_data = common;
2330 fsg->bulk_out_enabled = 1;
2331 common->bulk_out_maxpacket = usb_endpoint_maxp(fsg->bulk_out->desc);
2332 clear_bit(IGNORE_BULK_OUT, &fsg->atomic_bitflags);
2334 /* Allocate the requests */
2335 for (i = 0; i < fsg_num_buffers; ++i) {
2336 struct fsg_buffhd *bh = &common->buffhds[i];
2338 rc = alloc_request(common, fsg->bulk_in, &bh->inreq);
2341 rc = alloc_request(common, fsg->bulk_out, &bh->outreq);
2344 bh->inreq->buf = bh->outreq->buf = bh->buf;
2345 bh->inreq->context = bh->outreq->context = bh;
2346 bh->inreq->complete = bulk_in_complete;
2347 bh->outreq->complete = bulk_out_complete;
2350 common->running = 1;
2351 for (i = 0; i < common->nluns; ++i)
2352 common->luns[i].unit_attention_data = SS_RESET_OCCURRED;
2357 /****************************** ALT CONFIGS ******************************/
2359 static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
2361 struct fsg_dev *fsg = fsg_from_func(f);
2362 fsg->common->new_fsg = fsg;
2363 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2364 return USB_GADGET_DELAYED_STATUS;
2367 static void fsg_disable(struct usb_function *f)
2369 struct fsg_dev *fsg = fsg_from_func(f);
2370 fsg->common->new_fsg = NULL;
2371 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2375 /*-------------------------------------------------------------------------*/
2377 static void handle_exception(struct fsg_common *common)
2381 struct fsg_buffhd *bh;
2382 enum fsg_state old_state;
2383 struct fsg_lun *curlun;
2384 unsigned int exception_req_tag;
2387 * Clear the existing signals. Anything but SIGUSR1 is converted
2388 * into a high-priority EXIT exception.
2392 dequeue_signal_lock(current, ¤t->blocked, &info);
2395 if (sig != SIGUSR1) {
2396 if (common->state < FSG_STATE_EXIT)
2397 DBG(common, "Main thread exiting on signal\n");
2398 raise_exception(common, FSG_STATE_EXIT);
2402 /* Cancel all the pending transfers */
2403 if (likely(common->fsg)) {
2404 for (i = 0; i < fsg_num_buffers; ++i) {
2405 bh = &common->buffhds[i];
2407 usb_ep_dequeue(common->fsg->bulk_in, bh->inreq);
2408 if (bh->outreq_busy)
2409 usb_ep_dequeue(common->fsg->bulk_out,
2413 /* Wait until everything is idle */
2416 for (i = 0; i < fsg_num_buffers; ++i) {
2417 bh = &common->buffhds[i];
2418 num_active += bh->inreq_busy + bh->outreq_busy;
2420 if (num_active == 0)
2422 if (sleep_thread(common))
2426 /* Clear out the controller's fifos */
2427 if (common->fsg->bulk_in_enabled)
2428 usb_ep_fifo_flush(common->fsg->bulk_in);
2429 if (common->fsg->bulk_out_enabled)
2430 usb_ep_fifo_flush(common->fsg->bulk_out);
2434 * Reset the I/O buffer states and pointers, the SCSI
2435 * state, and the exception. Then invoke the handler.
2437 spin_lock_irq(&common->lock);
2439 for (i = 0; i < fsg_num_buffers; ++i) {
2440 bh = &common->buffhds[i];
2441 bh->state = BUF_STATE_EMPTY;
2443 common->next_buffhd_to_fill = &common->buffhds[0];
2444 common->next_buffhd_to_drain = &common->buffhds[0];
2445 exception_req_tag = common->exception_req_tag;
2446 old_state = common->state;
2448 if (old_state == FSG_STATE_ABORT_BULK_OUT)
2449 common->state = FSG_STATE_STATUS_PHASE;
2451 for (i = 0; i < common->nluns; ++i) {
2452 curlun = &common->luns[i];
2453 curlun->prevent_medium_removal = 0;
2454 curlun->sense_data = SS_NO_SENSE;
2455 curlun->unit_attention_data = SS_NO_SENSE;
2456 curlun->sense_data_info = 0;
2457 curlun->info_valid = 0;
2459 common->state = FSG_STATE_IDLE;
2461 spin_unlock_irq(&common->lock);
2463 /* Carry out any extra actions required for the exception */
2464 switch (old_state) {
2465 case FSG_STATE_ABORT_BULK_OUT:
2466 send_status(common);
2467 spin_lock_irq(&common->lock);
2468 if (common->state == FSG_STATE_STATUS_PHASE)
2469 common->state = FSG_STATE_IDLE;
2470 spin_unlock_irq(&common->lock);
2473 case FSG_STATE_RESET:
2475 * In case we were forced against our will to halt a
2476 * bulk endpoint, clear the halt now. (The SuperH UDC
2479 if (!fsg_is_set(common))
2481 if (test_and_clear_bit(IGNORE_BULK_OUT,
2482 &common->fsg->atomic_bitflags))
2483 usb_ep_clear_halt(common->fsg->bulk_in);
2485 if (common->ep0_req_tag == exception_req_tag)
2486 ep0_queue(common); /* Complete the status stage */
2489 * Technically this should go here, but it would only be
2490 * a waste of time. Ditto for the INTERFACE_CHANGE and
2491 * CONFIG_CHANGE cases.
2493 /* for (i = 0; i < common->nluns; ++i) */
2494 /* common->luns[i].unit_attention_data = */
2495 /* SS_RESET_OCCURRED; */
2498 case FSG_STATE_CONFIG_CHANGE:
2499 do_set_interface(common, common->new_fsg);
2500 if (common->new_fsg)
2501 usb_composite_setup_continue(common->cdev);
2504 case FSG_STATE_EXIT:
2505 case FSG_STATE_TERMINATED:
2506 do_set_interface(common, NULL); /* Free resources */
2507 spin_lock_irq(&common->lock);
2508 common->state = FSG_STATE_TERMINATED; /* Stop the thread */
2509 spin_unlock_irq(&common->lock);
2512 case FSG_STATE_INTERFACE_CHANGE:
2513 case FSG_STATE_DISCONNECT:
2514 case FSG_STATE_COMMAND_PHASE:
2515 case FSG_STATE_DATA_PHASE:
2516 case FSG_STATE_STATUS_PHASE:
2517 case FSG_STATE_IDLE:
2523 /*-------------------------------------------------------------------------*/
2525 static int fsg_main_thread(void *common_)
2527 struct fsg_common *common = common_;
2530 * Allow the thread to be killed by a signal, but set the signal mask
2531 * to block everything but INT, TERM, KILL, and USR1.
2533 allow_signal(SIGINT);
2534 allow_signal(SIGTERM);
2535 allow_signal(SIGKILL);
2536 allow_signal(SIGUSR1);
2538 /* Allow the thread to be frozen */
2542 * Arrange for userspace references to be interpreted as kernel
2543 * pointers. That way we can pass a kernel pointer to a routine
2544 * that expects a __user pointer and it will work okay.
2549 while (common->state != FSG_STATE_TERMINATED) {
2550 if (exception_in_progress(common) || signal_pending(current)) {
2551 handle_exception(common);
2555 if (!common->running) {
2556 sleep_thread(common);
2560 if (get_next_command(common))
2563 spin_lock_irq(&common->lock);
2564 if (!exception_in_progress(common))
2565 common->state = FSG_STATE_DATA_PHASE;
2566 spin_unlock_irq(&common->lock);
2568 if (do_scsi_command(common) || finish_reply(common))
2571 spin_lock_irq(&common->lock);
2572 if (!exception_in_progress(common))
2573 common->state = FSG_STATE_STATUS_PHASE;
2574 spin_unlock_irq(&common->lock);
2576 if (send_status(common))
2579 spin_lock_irq(&common->lock);
2580 if (!exception_in_progress(common))
2581 common->state = FSG_STATE_IDLE;
2582 spin_unlock_irq(&common->lock);
2585 spin_lock_irq(&common->lock);
2586 common->thread_task = NULL;
2587 spin_unlock_irq(&common->lock);
2589 if (!common->ops || !common->ops->thread_exits
2590 || common->ops->thread_exits(common) < 0) {
2591 struct fsg_lun *curlun = common->luns;
2592 unsigned i = common->nluns;
2594 down_write(&common->filesem);
2595 for (; i--; ++curlun) {
2596 if (!fsg_lun_is_open(curlun))
2599 fsg_lun_close(curlun);
2600 curlun->unit_attention_data = SS_MEDIUM_NOT_PRESENT;
2602 up_write(&common->filesem);
2605 /* Let fsg_unbind() know the thread has exited */
2606 complete_and_exit(&common->thread_notifier, 0);
2610 /*************************** DEVICE ATTRIBUTES ***************************/
2612 static DEVICE_ATTR(ro, 0644, fsg_show_ro, fsg_store_ro);
2613 static DEVICE_ATTR(nofua, 0644, fsg_show_nofua, fsg_store_nofua);
2614 static DEVICE_ATTR(file, 0644, fsg_show_file, fsg_store_file);
2616 static struct device_attribute dev_attr_ro_cdrom =
2617 __ATTR(ro, 0444, fsg_show_ro, NULL);
2618 static struct device_attribute dev_attr_file_nonremovable =
2619 __ATTR(file, 0444, fsg_show_file, NULL);
2622 /****************************** FSG COMMON ******************************/
2624 static void fsg_common_release(struct kref *ref);
2626 static void fsg_lun_release(struct device *dev)
2628 /* Nothing needs to be done */
2631 static inline void fsg_common_get(struct fsg_common *common)
2633 kref_get(&common->ref);
2636 static inline void fsg_common_put(struct fsg_common *common)
2638 kref_put(&common->ref, fsg_common_release);
2641 static struct fsg_common *fsg_common_init(struct fsg_common *common,
2642 struct usb_composite_dev *cdev,
2643 struct fsg_config *cfg)
2645 struct usb_gadget *gadget = cdev->gadget;
2646 struct fsg_buffhd *bh;
2647 struct fsg_lun *curlun;
2648 struct fsg_lun_config *lcfg;
2652 rc = fsg_num_buffers_validate();
2656 /* Find out how many LUNs there should be */
2658 if (nluns < 1 || nluns > FSG_MAX_LUNS) {
2659 dev_err(&gadget->dev, "invalid number of LUNs: %u\n", nluns);
2660 return ERR_PTR(-EINVAL);
2665 common = kzalloc(sizeof *common, GFP_KERNEL);
2667 return ERR_PTR(-ENOMEM);
2668 common->free_storage_on_release = 1;
2670 memset(common, 0, sizeof *common);
2671 common->free_storage_on_release = 0;
2674 common->buffhds = kcalloc(fsg_num_buffers,
2675 sizeof *(common->buffhds), GFP_KERNEL);
2676 if (!common->buffhds) {
2677 if (common->free_storage_on_release)
2679 return ERR_PTR(-ENOMEM);
2682 common->ops = cfg->ops;
2683 common->private_data = cfg->private_data;
2685 common->gadget = gadget;
2686 common->ep0 = gadget->ep0;
2687 common->ep0req = cdev->req;
2688 common->cdev = cdev;
2690 /* Maybe allocate device-global string IDs, and patch descriptors */
2691 if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
2692 rc = usb_string_id(cdev);
2693 if (unlikely(rc < 0))
2695 fsg_strings[FSG_STRING_INTERFACE].id = rc;
2696 fsg_intf_desc.iInterface = rc;
2700 * Create the LUNs, open their backing files, and register the
2701 * LUN devices in sysfs.
2703 curlun = kcalloc(nluns, sizeof(*curlun), GFP_KERNEL);
2704 if (unlikely(!curlun)) {
2708 common->luns = curlun;
2710 init_rwsem(&common->filesem);
2712 for (i = 0, lcfg = cfg->luns; i < nluns; ++i, ++curlun, ++lcfg) {
2713 curlun->cdrom = !!lcfg->cdrom;
2714 curlun->ro = lcfg->cdrom || lcfg->ro;
2715 curlun->initially_ro = curlun->ro;
2716 curlun->removable = lcfg->removable;
2717 curlun->dev.release = fsg_lun_release;
2718 curlun->dev.parent = &gadget->dev;
2719 /* curlun->dev.driver = &fsg_driver.driver; XXX */
2720 dev_set_drvdata(&curlun->dev, &common->filesem);
2721 dev_set_name(&curlun->dev, "lun%d", i);
2723 rc = device_register(&curlun->dev);
2725 INFO(common, "failed to register LUN%d: %d\n", i, rc);
2727 put_device(&curlun->dev);
2731 rc = device_create_file(&curlun->dev,
2733 ? &dev_attr_ro_cdrom
2737 rc = device_create_file(&curlun->dev,
2740 : &dev_attr_file_nonremovable);
2743 rc = device_create_file(&curlun->dev, &dev_attr_nofua);
2747 if (lcfg->filename) {
2748 rc = fsg_lun_open(curlun, lcfg->filename);
2751 } else if (!curlun->removable) {
2752 ERROR(common, "no file given for LUN%d\n", i);
2757 common->nluns = nluns;
2759 /* Data buffers cyclic list */
2760 bh = common->buffhds;
2761 i = fsg_num_buffers;
2762 goto buffhds_first_it;
2767 bh->buf = kmalloc(FSG_BUFLEN, GFP_KERNEL);
2768 if (unlikely(!bh->buf)) {
2773 bh->next = common->buffhds;
2775 /* Prepare inquiryString */
2776 if (cfg->release != 0xffff) {
2779 i = usb_gadget_controller_number(gadget);
2783 WARNING(common, "controller '%s' not recognized\n",
2788 snprintf(common->inquiry_string, sizeof common->inquiry_string,
2789 "%-8s%-16s%04x", cfg->vendor_name ?: "Linux",
2790 /* Assume product name dependent on the first LUN */
2791 cfg->product_name ?: (common->luns->cdrom
2792 ? "File-Stor Gadget"
2793 : "File-CD Gadget"),
2797 * Some peripheral controllers are known not to be able to
2798 * halt bulk endpoints correctly. If one of them is present,
2801 common->can_stall = cfg->can_stall &&
2802 !(gadget_is_at91(common->gadget));
2804 spin_lock_init(&common->lock);
2805 kref_init(&common->ref);
2807 /* Tell the thread to start working */
2808 common->thread_task =
2809 kthread_create(fsg_main_thread, common, "file-storage");
2810 if (IS_ERR(common->thread_task)) {
2811 rc = PTR_ERR(common->thread_task);
2814 init_completion(&common->thread_notifier);
2815 init_waitqueue_head(&common->fsg_wait);
2818 INFO(common, FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
2819 INFO(common, "Number of LUNs=%d\n", common->nluns);
2821 pathbuf = kmalloc(PATH_MAX, GFP_KERNEL);
2822 for (i = 0, nluns = common->nluns, curlun = common->luns;
2825 char *p = "(no medium)";
2826 if (fsg_lun_is_open(curlun)) {
2829 p = d_path(&curlun->filp->f_path,
2835 LINFO(curlun, "LUN: %s%s%sfile: %s\n",
2836 curlun->removable ? "removable " : "",
2837 curlun->ro ? "read only " : "",
2838 curlun->cdrom ? "CD-ROM " : "",
2843 DBG(common, "I/O thread pid: %d\n", task_pid_nr(common->thread_task));
2845 wake_up_process(common->thread_task);
2850 common->nluns = i + 1;
2852 common->state = FSG_STATE_TERMINATED; /* The thread is dead */
2853 /* Call fsg_common_release() directly, ref might be not initialised. */
2854 fsg_common_release(&common->ref);
2858 static void fsg_common_release(struct kref *ref)
2860 struct fsg_common *common = container_of(ref, struct fsg_common, ref);
2862 /* If the thread isn't already dead, tell it to exit now */
2863 if (common->state != FSG_STATE_TERMINATED) {
2864 raise_exception(common, FSG_STATE_EXIT);
2865 wait_for_completion(&common->thread_notifier);
2868 if (likely(common->luns)) {
2869 struct fsg_lun *lun = common->luns;
2870 unsigned i = common->nluns;
2872 /* In error recovery common->nluns may be zero. */
2873 for (; i; --i, ++lun) {
2874 device_remove_file(&lun->dev, &dev_attr_nofua);
2875 device_remove_file(&lun->dev,
2877 ? &dev_attr_ro_cdrom
2879 device_remove_file(&lun->dev,
2882 : &dev_attr_file_nonremovable);
2884 device_unregister(&lun->dev);
2887 kfree(common->luns);
2891 struct fsg_buffhd *bh = common->buffhds;
2892 unsigned i = fsg_num_buffers;
2895 } while (++bh, --i);
2898 kfree(common->buffhds);
2899 if (common->free_storage_on_release)
2904 /*-------------------------------------------------------------------------*/
2906 static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
2908 struct fsg_dev *fsg = fsg_from_func(f);
2909 struct fsg_common *common = fsg->common;
2911 DBG(fsg, "unbind\n");
2912 if (fsg->common->fsg == fsg) {
2913 fsg->common->new_fsg = NULL;
2914 raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
2915 /* FIXME: make interruptible or killable somehow? */
2916 wait_event(common->fsg_wait, common->fsg != fsg);
2919 fsg_common_put(common);
2920 usb_free_descriptors(fsg->function.descriptors);
2921 usb_free_descriptors(fsg->function.hs_descriptors);
2922 usb_free_descriptors(fsg->function.ss_descriptors);
2926 static int fsg_bind(struct usb_configuration *c, struct usb_function *f)
2928 struct fsg_dev *fsg = fsg_from_func(f);
2929 struct usb_gadget *gadget = c->cdev->gadget;
2933 fsg->gadget = gadget;
2936 i = usb_interface_id(c, f);
2939 fsg_intf_desc.bInterfaceNumber = i;
2940 fsg->interface_number = i;
2942 /* Find all the endpoints we will use */
2943 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_in_desc);
2946 ep->driver_data = fsg->common; /* claim the endpoint */
2949 ep = usb_ep_autoconfig(gadget, &fsg_fs_bulk_out_desc);
2952 ep->driver_data = fsg->common; /* claim the endpoint */
2955 /* Copy descriptors */
2956 f->descriptors = usb_copy_descriptors(fsg_fs_function);
2957 if (unlikely(!f->descriptors))
2960 if (gadget_is_dualspeed(gadget)) {
2961 /* Assume endpoint addresses are the same for both speeds */
2962 fsg_hs_bulk_in_desc.bEndpointAddress =
2963 fsg_fs_bulk_in_desc.bEndpointAddress;
2964 fsg_hs_bulk_out_desc.bEndpointAddress =
2965 fsg_fs_bulk_out_desc.bEndpointAddress;
2966 f->hs_descriptors = usb_copy_descriptors(fsg_hs_function);
2967 if (unlikely(!f->hs_descriptors)) {
2968 usb_free_descriptors(f->descriptors);
2973 if (gadget_is_superspeed(gadget)) {
2976 /* Calculate bMaxBurst, we know packet size is 1024 */
2977 max_burst = min_t(unsigned, FSG_BUFLEN / 1024, 15);
2979 fsg_ss_bulk_in_desc.bEndpointAddress =
2980 fsg_fs_bulk_in_desc.bEndpointAddress;
2981 fsg_ss_bulk_in_comp_desc.bMaxBurst = max_burst;
2983 fsg_ss_bulk_out_desc.bEndpointAddress =
2984 fsg_fs_bulk_out_desc.bEndpointAddress;
2985 fsg_ss_bulk_out_comp_desc.bMaxBurst = max_burst;
2987 f->ss_descriptors = usb_copy_descriptors(fsg_ss_function);
2988 if (unlikely(!f->ss_descriptors)) {
2989 usb_free_descriptors(f->hs_descriptors);
2990 usb_free_descriptors(f->descriptors);
2998 ERROR(fsg, "unable to autoconfigure all endpoints\n");
3003 /****************************** ADD FUNCTION ******************************/
3005 static struct usb_gadget_strings *fsg_strings_array[] = {
3010 static int fsg_bind_config(struct usb_composite_dev *cdev,
3011 struct usb_configuration *c,
3012 struct fsg_common *common)
3014 struct fsg_dev *fsg;
3017 fsg = kzalloc(sizeof *fsg, GFP_KERNEL);
3021 fsg->function.name = FSG_DRIVER_DESC;
3022 fsg->function.strings = fsg_strings_array;
3023 fsg->function.bind = fsg_bind;
3024 fsg->function.unbind = fsg_unbind;
3025 fsg->function.setup = fsg_setup;
3026 fsg->function.set_alt = fsg_set_alt;
3027 fsg->function.disable = fsg_disable;
3029 fsg->common = common;
3031 * Our caller holds a reference to common structure so we
3032 * don't have to be worry about it being freed until we return
3033 * from this function. So instead of incrementing counter now
3034 * and decrement in error recovery we increment it only when
3035 * call to usb_add_function() was successful.
3038 rc = usb_add_function(c, &fsg->function);
3042 fsg_common_get(fsg->common);
3047 /************************* Module parameters *************************/
3049 struct fsg_module_parameters {
3050 char *file[FSG_MAX_LUNS];
3051 bool ro[FSG_MAX_LUNS];
3052 bool removable[FSG_MAX_LUNS];
3053 bool cdrom[FSG_MAX_LUNS];
3054 bool nofua[FSG_MAX_LUNS];
3056 unsigned int file_count, ro_count, removable_count, cdrom_count;
3057 unsigned int nofua_count;
3058 unsigned int luns; /* nluns */
3059 bool stall; /* can_stall */
3062 #define _FSG_MODULE_PARAM_ARRAY(prefix, params, name, type, desc) \
3063 module_param_array_named(prefix ## name, params.name, type, \
3064 &prefix ## params.name ## _count, \
3066 MODULE_PARM_DESC(prefix ## name, desc)
3068 #define _FSG_MODULE_PARAM(prefix, params, name, type, desc) \
3069 module_param_named(prefix ## name, params.name, type, \
3071 MODULE_PARM_DESC(prefix ## name, desc)
3073 #define FSG_MODULE_PARAMETERS(prefix, params) \
3074 _FSG_MODULE_PARAM_ARRAY(prefix, params, file, charp, \
3075 "names of backing files or devices"); \
3076 _FSG_MODULE_PARAM_ARRAY(prefix, params, ro, bool, \
3077 "true to force read-only"); \
3078 _FSG_MODULE_PARAM_ARRAY(prefix, params, removable, bool, \
3079 "true to simulate removable media"); \
3080 _FSG_MODULE_PARAM_ARRAY(prefix, params, cdrom, bool, \
3081 "true to simulate CD-ROM instead of disk"); \
3082 _FSG_MODULE_PARAM_ARRAY(prefix, params, nofua, bool, \
3083 "true to ignore SCSI WRITE(10,12) FUA bit"); \
3084 _FSG_MODULE_PARAM(prefix, params, luns, uint, \
3085 "number of LUNs"); \
3086 _FSG_MODULE_PARAM(prefix, params, stall, bool, \
3087 "false to prevent bulk stalls")
3090 fsg_config_from_params(struct fsg_config *cfg,
3091 const struct fsg_module_parameters *params)
3093 struct fsg_lun_config *lun;
3096 /* Configure LUNs */
3098 min(params->luns ?: (params->file_count ?: 1u),
3099 (unsigned)FSG_MAX_LUNS);
3100 for (i = 0, lun = cfg->luns; i < cfg->nluns; ++i, ++lun) {
3101 lun->ro = !!params->ro[i];
3102 lun->cdrom = !!params->cdrom[i];
3103 lun->removable = !!params->removable[i];
3105 params->file_count > i && params->file[i][0]
3110 /* Let MSF use defaults */
3111 cfg->vendor_name = 0;
3112 cfg->product_name = 0;
3113 cfg->release = 0xffff;
3116 cfg->private_data = NULL;
3119 cfg->can_stall = params->stall;
3122 static inline struct fsg_common *
3123 fsg_common_from_params(struct fsg_common *common,
3124 struct usb_composite_dev *cdev,
3125 const struct fsg_module_parameters *params)
3126 __attribute__((unused));
3127 static inline struct fsg_common *
3128 fsg_common_from_params(struct fsg_common *common,
3129 struct usb_composite_dev *cdev,
3130 const struct fsg_module_parameters *params)
3132 struct fsg_config cfg;
3133 fsg_config_from_params(&cfg, params);
3134 return fsg_common_init(common, cdev, &cfg);